Saturday, December 16, 2023

The Christmas Blizzard - Anatomy of a Weather Catastrophe

 The Christmas Blizzard
Buffalo, NY - December 23-26, 2022

Anatomy of a Weather Catastrophe

by Tom Niziol

Figure 1: Christmas morning 2022, looking at Transit Rd. from the Sheridan Drive overpass after most of the snow and wind had diminished from 2 full days of whiteout conditions. This lake-effect snow blizzard was a Weather Catastrophe that ended up taking 47 lives. (photo credit NYSDOT)



Introduction

During the Christmas holiday weekend of 2022, Buffalo, NY was buried by a catastrophic lake-effect snow blizzard. Over the course of nearly 4 days, forty-seven people lost their lives as a direct result of the winter storm.  This begs an answer to the question “How could the most winter savvy-city in the world, in the year 2022, backed by sophisticated numerical weather models and exceptional communication networks suffer such a tremendous loss of life?”

It all is part of the process that I describe as a “Weather Catastrophe”, where several meteorological as well as logistical and societal factors, each of which produces its own impacts on the public, come together at the wrong place and the wrong time. The result follows the old saying that “The Whole is Sometimes MUCH Greater Than the Sum of the Parts”.  In this presentation I plan to piece together those parts to highlight how catastrophes like this one happen and hopefully, how we all can be better prepared when it happens again, because history does repeat itself.


Fig 2: Storm total snowfall, December 23-27, 2022. Note 3 narrow strips of heaviest snowfall downwind of Lake Erie, one to the north of Buffalo, one south, and one directly over the city. The greatest snowfall was recorded in North Tonawanda at 59.7", just north of downtown Buffalo, followed closely behind by the Buffalo airport, about 7 miles east of downtown, with 51.9"


Buffalo's Location and Lake-effect Snow

Buffalo has a well-deserved reputation for snow. With an annual snowfall just this short of 100”, it regularly deals with impactful lake-effect snowstorms. Most of them result in lots of travel woes but fatalities directly attributed to these storms are usually quite low.

Fig 3: The average annual snowfall, recorded at the Buffalo airport, based on monthly climate normals from 1991-2020. 

Citizens of Buffalo, NY often have to hear comments like “Buffalo, isn’t that where it snows every day in winter?” or “how do you handle that much snow?”, when they travel anywhere in the world.  In fact, Buffalonians wear that badge of honor, noting how they are used to it and except for having to drive in the snow and shovel it, they actually don’t mind it that much.

The snowy reputation has everything to do with the location of Buffalo on the eastern tip of 225-mile Lake Erie, one of 5 Great Lakes that are often described more like “inland fresh water seas” because of their massive size. In fact, the Great Lakes overall have a surface area that exceeds that in 39 of the 50 states. The Great Lakes are so large they make weather all their own and the most infamous type of weather are mesoscale (or small scale) lake-effect snowstorms. 

Fig 4: Lake Erie is over 225 miles long and up to 60 miles wide. It has a surface area nearly 10,000 square miles. It would take over 4 hours of driving to get from one end of the lake to the other. 

Those high-impact snowstorms occur when cold air from Canada sweeps down across the relatively warm water of the Great Lakes. The water stays warm for a much longer period than the air temperature going into the winter because of water’s ability to hold heat for a longer period of time, and the bigger the body of water, the longer it takes to cool. When that cold air moves across the warmer water, heat and moisture are transferred into the air. The warmed and moistened buoyant air parcels rise, rapidly cool and moisture quickly condenses into snow crystals which build into millions of snowflakes. 

Fig 5: When cold air from Canada crosses the warmer water of the Great Lakes, heat and moisture rise from the lake. As the air parcels rise into the colder air, moisture is turned into snow crystals that collect into millions of snowflakes in those clouds. The wind aligns and directs those clouds downwind of the lakes across places like Buffalo, NY. 

The wind direction determines where all of that snow will eventually be deposited downwind of the Great Lakes and the type of snowbands that occur. Multiple banded snows occur when winds are directed across the shorter axis of lakes like Lake Erie or wide expanses of irregularly-shaped bodies of water like Lake Superior. Although they may cover a greater area with snowfall, they are generally much weaker than their counterparts. They are formed under horizontal or parallel roll convergence and produce many wind-parallel bands of weak convection.

When winds are aligned down the long axis of elliptically-shaped lakes like Lake Erie, single "mega-bands" of snow develop. That's because winds from those two parallel shores undergo frictional and heat differences that result in convergence over the narrow body of water to produce that one "mega-band" of snow. The prevailing winds within the cloud layer extend the convective snow clouds along that strong convergence zone far inland. The band might only be 10 to 15 miles wide while stretching over 100 miles at time. These are the bands that produce snowfall rates of up to 6" per hour, and often thundersnow as well. Lake Erie is designed to take full advantage of the prevailing WSW winds during late Fall and Winter to produce these mega-bands which often set up right over Buffalo and its suburbs.  

 
Fig 6: Multiple snowbands develop over the shorter fetch of elliptically-shaped lakes or over irregularly shaped bodies of water. Single bands develop along the long axis of elliptically shaped lakes such as Lakes Erie and Ontario

In the radar loops below, I compare the multiple-banded snows on Lake Superior (left) with a single mega-band of snow off Lake Erie (right). 

Fig 7: Two types of lake-effect snow bands. Multiple banded snows, often referred to as horizontal roll convection, develop when winds are directed across wide or irregularly-shaped lakes like Lake Superior (left) or the shorter fetch of elliptically-shaped lakes like Lake Erie.  When winds blow down the long axis of narrow, elliptically-shaped lakes like Lake Erie (right), frictional and heat differences between the land and lake cause winds to converge over the middle of that long, narrow body of water. This results in a single, narrow convergence zone over the center of the lake, producing a mega-band of snow falling at rates up to 6" per hour. 


In the heart of that narrow band, snowfall rates can exceed 6 inches per hour and sometimes be accompanied by thundersnow. Ironically, Buffalo, NY positioned at the northeast tip of the SW-NE oriented lake is an almost perfect location to be on the receiving end of these storms. It can be fun but frustrating to live everyday lives when these storms occur. While your neighbors just a few miles north of you are under sunny skies, you may be in the heart of a whiteout blizzard. Several hours later as winds shift just a few degrees, the snowband may migrate up to your neighbor’s place and the entire situation becomes reversed. 

The image below shows a view of the snowcover a couple days after the November 17-19, 2022 lake-effect snowstorm. It highlights just how small the scale of these storms can be!  Below that is a series of radar images showing a 12-hour period during that storm. You can see how that extremely narrow band of heavy snow moved from Buffalo northward to Niagara Falls. At one point the width of the snowband was as little as 12 miles. For residents trying to go about their daily lives, this presents a big challenge. 

Fig 8: The November 2022 lake-effect snow event dropped as much as 81" of snow in parts of Western New York. This visible satellite image from a few days after the storm highlights just how narrow the swath of snow can be. Travelling from the Southtowns to Northtowns in Western New York would take you from green grass through deep snow and back to green grass again. 

 

Fig 9: This radar animation from November, 18-19, 2022 is an example of how subtle shifts in the wind direction can move snowbands from one area to the next. In the above radar animation, a gradual wind shift from W (265°) to SW (250°) and eventually SSW (230°) moved the snowband from suburbs south of Buffalo, through the city and eventually to suburbs north of Buffalo over the course of just 12 hours.

 

If you are caught under one of these bands of snow, it can be scary. The image below is from the November 2014 lake-effect snowstorm that hit Buffalo, NY. You are looking toward the south, at the north wall of the snowband. Driving into that wall of snow is surreal. You literally go from clear skies into a whiteout, where you can barely see 10 or 20 feet in front of you.  Travel can become impossible because you cannot see the street and the snow comes down at such a rate that it quickly piles up. 4-wheel drive vehicles may become useless because even though they can get through the deep snow, they cannot see anywhere and other vehicles often block the road ahead of them. Fortunately, in most cases these storms don’t last for more than a day or so and temperatures aren’t exceptionally cold so you can survive them if you are caught in your vehicle, as long as you have a full tank of gas and the winter supplies to keep you hydrated, fed and warm until the storm passes. However, there is always the potential that one of these storms will become much worse and that is what happened during Christmas Holiday 2022 in Buffalo. 


Fig 10: View from downtown Buffalo looking toward the south of the north wall of a lake-effect snowstorm in November 2014. Driving into this band is surreal, going from clear skies into a rgaing whiteout within a few hundred yards of entering the storm. (Photo credit Shawn Smith via NOAA / NOAA)


Historical Storm - Blizzard of '77

Buffalo’s snowy reputation was cemented into history during the month of January 1977. That winter of 76-77 was brutal for much of the US. In fact, January ’77 is the second-coldest month in recorded US history, and for the Eastern US it was the coldest January on record. In Buffalo, NY, it had been so cold leading up to the month that Lake Erie had frozen over by mid-December. In fact, an astonishing snow depth of 51” was reported in Buffalo on the morning of January 27.

That day started out very serene for January, with a balmy mid-winter temperature of 25 degrees at mid-morning. However, at 11:30AM an exceptionally strong Arctic front swept across the region and Buffalo was in the throws of a 5-day blizzard like they had never seen. Before it was all over, 29 people lost their lives in this storm, many buried by snow, frozen in the cars. Officials vowed this would never happen again. But Nature has a mind of its own and history DOES repeat itself. 

Fig 11: Photos from the Blizzard of 77'. News reporters (left) are walking across the tops of cars buried in the snow next to the runway at the Buffalo airport. Red Cross workers (right) using snowmobiles to get around check cars by pounding on roofs for survivors. (photo credit Buffalo News: Robert Smith)


Pre-Cursor to The Big Event - November 17-19, 2022

Fast-forward to late Fall and early Winter of 2022 which was topsy-turvy weatherwise for Buffalo residents. An early season lake-effect snowstorm during November 17-19 (shown in previous images), dropped unbelievable amounts of snow from the city to the heavily populated suburbs south of the city (known as The Southtowns). The Buffalo airport recorded 36.6” of snow from this multi-day storm, and that paled in comparison to the snow that piled up in the Southtowns where Hamburg, NY, received 81” and Orchard Park, home of the NFL Buffalo Bills accumulated 80”. The snowfall map below shows the incredible gradient of snowfall as one travelled from south to north through the city of Buffalo. 

Travel impacts from the event were significant, but there were fortunately only 2 deaths in the Buffalo area attributed to the storm, both from heart attacks shoveling snow. Yes, there was tremendous snowfall from this storm. However, sustained winds were not that strong during the event, generally below 20 mph. Temperatures were also quite mild, only dropping to 23 degrees. Also, the lake-effect storm fired up during the overnight hours, south of Buffalo, and when it did move north through the city on the 3rd day of the event, that was also during the overnight hours when there was very little traffic on roads. Simply put, very few people were outiside in the elements.

Surprisingly, the rest of the month was so warm, that by the 30th, every bit of up to 80" of snow had melted. Even more bizarre, through the first 22 days of December, the high temperature each day exceeded 30 degrees.



Fig 12: Storm total snowfall for the November 16-21, 2022 lake-effect snow event. As much as 81" of snow was measured in the town of Hamburg, just south of the city of Buffalo.


The Big Event - December 23-26, 2022

Five weeks later, in the days leading up to the busy 2022 Christmas Holiday, NWS Buffalo forecasters were looking at very foreboding signs of what was being advertised by the sophisticated computer models as a multi-day, high impact lake-effect snowstorm. In fact, by comparing the model data with past lake-effect snowstorms, a method known as analogs, it was apparent this upcoming storm was no garden variety lake-effect snowstorm that winter savvy citizens of Buffalo are all too familiar with. No, this storm was going to be much worse. But worse than the 80” lake-effect storm that pummeled the area back in November?  Possibly, due to many other factors, and forecasters realized it could be so impactful that they even stated on one of their daily forecast discussions that this could be a ”once in a generation” storm.

The large-scale weather pattern setting up to produce this epic storm was textbook. Several thousand feet in the atmosphere, the winter jet stream was buckling to bring exceptionally cold air down from the north pole, right across the Great Lakes. An Upper Level Low at 500mb was predicted to close off right over James Bay Canada, the perfect spot to set up conditions in the lower atmosphere to produce an intense, single band snowstorm off Lake Erie. When the jet stream closes off these Lows, they slow down their eastward movement, assuring an extended period of winds that blow out of one particular direction. It also provides a deep column of cold air to allow storms to grow several thousands of feet into the atmosphere. In the world of lake-effect snow, as long as conditions of deep, cold air and the same wind direction remain in place, these narrow intense bands of snow will remain stationary over one particular location, pummeling the area with blizzard conditions at times.

Fig 13: 500mb analyses from December 21-26, 2023.  You can see how the 500mb Low closes off and sets up over James Bay Canada, a perfect location to produce lake-effect snow over Buffalo. Note, the reports from Buffalo, NY were not available from December 24 through 26 because it was not possible to launch a weather balloon in those blizzard conditions.   

At the surface, the Low pressure system was set to undergo very rapid deepening, or strengthening. In fact, the central pressure of the Low dropped an astounding 35mb in 24 hours, far surpassing the requirement to label the storm as a "bomb" in meteorological terms, defined as a drop in central pressure of 24mb or more in 24 hours. These "bombs" are more likely to occur in the massive and powerful storms along the east coast in winter, known as Nor'easters. However, they do occur in the Grear Lakes region as well. Once one of these monsters swings through, the storminess is usually replaced by windy, colder and clearing conditions. But in this part of the world during the late Fall through Winter, as Barney Wiggins, the head of the National Weather Service way back over 75 years ago said, "the weather often clears up sotrmy on the Great Lakes". 

Fig 14: The Low responsible for the lake-effect blizzard dropped an astounding 35mb in 24 hours from 1005mb on December 23 at 00z to 970mb on December 24 at 00z, undergoing the rapid deepening known as "bombogenesis".


The animation shown below is from the NAM model and shows the snowbands in blue at one-hour intervals from Friday evening at 7PM, some 10 hours after the blizzard began and goes for over 48 hours, through Sunday night. Unfortunately, it is the only model run I kept in my archives as I was downloading data in real-time for the event. However, this gives you some idea of what forecasters would have been looking at. Even a couple of days before the storm struck, models were showing these types of solutions. What is striking from the animation is how stationary that band is, remaining over the Buffalo area for the course of 2 days before it was forecast to migrate southward before daybreak on Sunday, Christmas Day. Yes, other bands of lake-effect snow were forecast to occur off all of the Great Lakes, but none would be as intense and stationary as the Lake Erie band, and most importantly, none of the other bands were parked over a metro area with a population greater than one million people. 
 

Fig 15: 60-hr NAM model initialized at 18z (1PM EST) on Fri December 23, 2022. Note, the blizzard had already been going for 6 hours when this model started. This is a great example of the "steady-state" nature of these types of lake-effect storms. Once the band sets up, as long as the wind direction does not change, one area could be under the "firehose" of snow for hours to days. 


Friday, December 23, 2022 in Western New York was going to be busy. On the last weekday and second last shopping day until Christmas, just about everyone was going to be out doing something.  Even with an ominous forecast for a lake-effect snowstorm, many people were likely going to take their chances and get to work, shop a little and get home before the storm got “too bad”. Schools had already shut down to add one day early for the Christmas Break after officials had been briefed about the lake-effect storm by the NWS. 

The morning was eerily similar to a morning almost 45 years previous to that back in January 1977. The temperature at 6AM was 37 degrees under a little light rain and wind easterly winds at 5 mph. As people got ready for work, they might have wondered about the accuracy of the impending winter warnings for a big storm. 

As most traffic headed into work at 7AM conditions were still tranquil with a temperature of 34 degrees and light rain and fog dropping visibility to 1.5 miles and 9 mph winds. Just as everyone was getting into work, at 7:43 AM, the cold front slammed into Buffalo as winds howled, gusting to 40 mph. By 8:00 AM the rain changed over to light snow. Out over the lake, the Buffalo weather radar was showing the lake-effect snowband rapidly developing and setting its sights on Buffalo. At 8:06 AM the visibility dropped to 1/2 mile in moderate snow and winds were now gusting to 60 mph. By 8:39 AM visibility was down to 1/4 mile in heavy snow and 8 minutes later a full whiteout was occurring with visibility down to 1/8 mile. Whiteout conditions meant nobody was going to be going anywhere soon.  What transpired over the next 72 hours will be ever etched into the minds and souls of Buffalo residents as a fierce blizzard brought the city and its immediate suburbs to a standstill.

Fig 16: The table shows the weather observations from the Buffalo airport.  Look at how rapidly conditions deteriorated when the storm hit during and just after the height of the Friday morning rush hour. 

Fig 17: This video was taken on that Friday around 11AM by Reed Timmer near the waterfront in downtown Buffalo. You can hear and feel the raw power of the storm as it ramps up. Visibility was already dropping to zero at times in whiteouts. If you are caught outside in this type of weather, it is almost impossible to get to safety because you cannot see where you are going. 


By 11 AM on December 23, under whiteout conditions, the temperature had dropped to 21 degrees with winds gusting to 67 mph and a wind chill of just one degree above zero. If you were not at home, you had a choice, either try to brave the elements to go out and get home or hunker down and wait.  Traffic became stuck in its place in many locations. As the afternoon wore on, conditions got even worse as the temperature continued to plummet. By 5PM it was 7 degrees and with winds gusting to 60 mph the wind chill had dropped to a dangerous -20 degrees. By midnight, some 14 hours after the storm hit, the Buffalo airport had received 22.6” of snow, with other locations close by getting even more. The tremendous winds piled snow drifts to height of 6 ft. or more, burying vehicles stuck in their place with potential victims inside.

Fig 18: The hourly weather observations from the Buffalo airport show that from 9AM through the rest of the day and night, the area was under whiteout conditions in heavy snow and winds gusting over 60 mph at times. 

The video below is taken by Reed Timmer, who was in Buffalo through the entire storm. It highlights just how deep the snowdrifts got as the storm howled for hours on end. He notes how he is actually standing on top of snow drifts up to 10 ft. tall. You can easily see from this video how cars got stuck in these drifts and how easily they would have been covered completely by snow. If the tailpipe on the car gets blocked with snow, carbon monoxide poisoning can result, the vehicle becomes a death trap. 

Fig 19: Reed Timmer is standing on top of snow drifts that were as high as 10 ft. in this video clip. You can see cars almost completely buried under these drifts. Travel is impossible in these conditions. 

It’s hard to fathom the fact that the area in and around the city of Buffalo would remain in a whiteout through the entire night and ALL of Christmas Eve. Daybreak on December 24th brought a temperature of 3 degrees and a wind chill of -22 with zero visibility still being recorded out at the Buffalo airport.  The rest of that entire day and evening the winds gusted in the 40-50 mph range with wind chills in the minus teens. Visibility remained near or at zero in the whiteout conditions that piled snow drifts even higher. Emergency vehicles could not even get out to conduct operations because it was just too dangerous. Another 17.9” was officially recorded at the airport by midnight bringing the storm total to 40.5” of heavily drifted, wind-blown snow as the region headed into Christmas Day. 

Fig 20: Christmas Eve was also one for the record books. It is almost unfathomable to think that the entire 24-hour period featured whiteout conditions in a raging blizzard, and that was an extension of the 21 hours of blizzard conditions from December 2. Winds gusted well over 40 mph for almost that entire time and winds chills bottomed out at -22°. 


As dawn broke on Christmas Day the city and surrounding suburbs looked like an Arctic wasteland.  The narrow, intense band of lake-effect snow had moved south overnight, now impacting the Southtowns. Over the city and surrounding suburbs, the visibility gradually rose to 1 to 3 miles in blowing snow. The winds continued to howl with gusts over 30mph and the wind chills in the single digits. Nobody was going anywhere however, with drifts several feet tall covering almost all thoroughfares. The Buffalo International Airport, renowned worldwide for its plow operators’ snow-fighting skills, remained closed, not opening until 3 days later. There was light however at the end of the tunnel, as the parent large scale, Upper-Level Low that was parked over James Bay Canada was showing signs of weakening and beginning to move eastward.

Fig 21: This photo was taken at 9:30AM on Christmas day, looking from the Sheridan Drive overpass at Transit Rd. east of the city of Buffalo. By this time, plows had cleared one lane of traffic but getting your vehicle dug out was another problem altogether. (Photo credit: NYSDOT)

But Mother Nature had one more punch to throw at Buffalo that night. In the wee hours of Monday morning, the winds briefly shifted from westerly to southwest again and the snowband that was well south of Buffalo began to migrate northward, sweeping through the city before dawn on Monday December 26. Even though it dumped another 7+ inches of snow across the region, after all that had happened, it didn’t seem like much, and fortunately it was still dark when it came through the region, sparing those who were sleeping one more nightmare of whiteout conditions.    

A radar animation through the entire storm history below shows what happens when winds line up down the long fetch of the lake. The snowband persisted for hour upon hour over Buffalo and immediate suburbs, before slight shifts in the winds allowed the band to migrate north, south and then north one more time before finally weakening as the wind direction shifted to SSW and took the band off the long axis of the lake. Note that even when the band had moved north of the city of Buffalo and the airport, located about 7 miles east of the city, the visibility was still near zero in whiteout conditions. That was due to the very strong winds whipping up and drifting the nearly 2 ft. of snow that had already fallen. 

Fig 22: Hourly radar animation through the history of the blizzard with the wind speed, direction and wind chill at approximately the time of the radar image. The 3 main metro areas of Buffalo are highlighted here to show how very slight changes in the wind direction positioned the band over an entirely different part of town, You can also see how many times the band oscillated across the region. 

By late Monday those tallying up snowfall totals showed over 4 feet of snow (50.6”) had been measured at the Buffalo Airport. Three days of exceptionally strong winds had piled drifts over 10 ft. tall in some areas. It would still be a few days before life began to get back to normal. Clearing snow from streets involved first checking buried vehicles for possible victims inside, then moving those vehicles before front end loaders could come in and break through snowdrifts that would allow plows to clear the roads. Residents had the difficult task of removing snow from their driveways. Once again, because of the snow drifts, many had to bring in plow operators with heavier equipment to remove the snow.

In the wake of the catastrophe, harrowing stories emerged of survivors and those who became victims of this wicked storm. My own friend was one of those survivors. I had told he and his wife on the morning of the start of the blizzard to make sure he was hunkered down and set to stay put for at least a couple days. His wife left work early as the storm hit. She brought her friend home with her and the three of them decided to venture out and take her friend home before it got “too rough”. They drove south from the north side of the city right into the teeth of that snowband. After dropping their friend off they turned back to head home. A few miles later, in the heart of the whiteout, they drove their vehicle off the road and into a snowbank. They were now stuck, reality set in. They could not see a thing outside. They had an idea of where they were and checked on their GPS but nobody, AAA, even EMS personnel could go out in the storm by now. They knew a close friend who was a realtor and miraculously, had a house she was showing within a couple blocks of where they were stuck. They called her and she gave them the key code to get into the vacant house.  In a harrowing walk through the whiteout, they managed to get to the house, which still had its heat turned on, and survived the night and the next day. Without that Guardian Angel, they may not have survived. So many people caught outside, either walking or in their cars, were not that lucky.


Lessons Learned

When the final numbers were tallied, 47 people lost their lives in this storm. According to a post made by Erie County (where Buffalo is located) Executive Mark Poloncarz, the fatalities were listed under the following causes:


Fig 23: Social media post from Erie County Executive, Mark Poloncarz, listing the fatalities. One other fatality was attributed to the storm in Niagara county, just north of Erie county. 


National Grid, the company that maintains the power grid in Western New York, noted that there were over 104,000 people without power at one point during the blizzard, and many of those were without power for several days. 

There was a lot of finger-pointing as the storm unfolded and after the catastrophe began to wind down. City and county officials were criticized for not acting sooner to impose driving bans. They posted a driving ban 9AM that Friday morning, but it was after the storm began. The visibility had dropped to 1/8 mile by that time and winds were already clocked at 68mph. According to the Washington Post "New York's second-largest city has gone for years without an official emergency manager, whose job it is to create "procedures for responding to natural disasters and other emergencies" and lead and help coordinate the response."

The National Weather Service had been talking for days before the storm hit of the potential impacts from this storm. They even used the term “once in a generation”. But what does that term really mean to the public? I refer back again to the lake-effect storm that occurred just one month previous to this one, which dropped over 3 feet of snow in Buffalo and as much as 80” in the Southtowns and only resulted in 2 fatalities. How could this one be any worse?

This is where awareness, from the forecasters, Emergency Management officials, politicians and the public must be raised to the next level to communicate the combination of factors that would turn this storm into a catastrophe.  It is my definition of a Weather Catastrophe, where several factors come together at the wrong place and time and that combination of factors has much greater impact than any taken individually. The whole becomes much greater than the sum of the parts. I have seen this so many times in my career that it begs for better tools to “flag” when a weather event crosses that line and becomes a catastrophe.

Let’s look at each factor and how they combined to produce the catastrophe. I split them into meteorological, logistical and societal factors in the table below. These are my own opinions and they may not be the only answers to what led to the catastrophe but I feel they address the most important aspects of the event.

Fig 24: Table that shows the author's opinion of the factors that went into creating a weather catastrophe for the lake-effect blizzard of December 23-26, 2023. 

From the meteorological standpoint, the flowchart below helps to explain the concept of several impactful weather factors combining to produce much greater overall impacts on the public. The chart identifies the weather factors in gray.

Fig 25: Flowchart that shows how the impacts of the combination of meteorological factors can be multiplied many more times compared to each individual factor. The whole is MUCH greater than the sum of the parts.  

Heavy snow typically causes traffic problems. Strong winds can take down tree limbs and cause power outages. Arctic temperatures in northern latitudes don’t necessarily freeze pipes etc. but they can prove impactful to vehicles not prepared for winter conditions and certainly can be dangerous to anyone spending a lot of time outside without adequate winter gear.

The impacts notch up VERY quickly though when you begin to combine these factors. In the chart above, the combination of heavy snow and strong winds produces whiteouts, making travel VERY dangerous. Snow begins to drift rapidly to block roads. Vehicles get stranded in those drifts, blocking other traffic. Strong winds and Arctic temperatures combine to produce dangerous wind chills. It greatly decreases the time one can spend outside without getting frostbite and hypothermia. When those 3 original factors are combined, the impacts increase at an even greater rate. To try to travel in any way when the region is experiencing heavy snow, strong winds and arctic temperatures is impossible. You almost certainly will get stranded in a vehicle and when you do, you now are looking the at very real possibility of freezing if you cannot get to safety. The only hope is that the storm abates soon enough to allow you to get to safety. 

This is where the storm duration comes into play. It raises the impacts exponentially by making it necessary to survive life-threatening conditions for an extended period of time. In this case, storm duration was the “straw that broke the camel's back”. For those who were stranded outside, freezing to death was almost certain. In addition, for those who were inside and lost power, heating their homes became impossible in many cases. Even for those in unheated shketer, the duration of the bitter cold wind chills became life-threatening. This combination of factors is how a weather catastrophe occurs.

The time of day and day of week the storm struck were very important logistical factors in my assesment. Because the weather was calm as most people were waking up and heading into work, there may have been a false sense of security to "go out and get things done before the storm hit".  Finally, as with some of the most deadly historical blizzards that have occurred in the U.S., one other factor was extemely important. This storm hit so quickly and conditions deteriorated so rapidly, that nobody had time to respond and get back home or to safety. Remember, the weather essentially went from calm conditions to a raging blizzard in 1 hour, then continued as a full-blown whiteout blizzard for the better part of nearly 3 days. Total up all of these factors and you can easily see how they eventually tip the scales to create a Weather Catastrophe.

Fig 26: The scale shows how each factor plays a role in impacts, and as they pile on, the impacts become greater and greater until that final factors, the duration of the event, tips the scale into a weather catastrophe. 

Going forward, I believe it is extremely important to tie together all of the important meteorological, logistical and even societal factors in assessing the potential, full impacts of catastrophic weather events.  I strongly feel this is one area where AI-type systems may be a tremendous help. They have the ability to integrate thousands of parameters from past events, to flag the possibility of that “one in a million” combination of factors that could lead to a Weather Catastrophe. Those factors could even be tailored for location, so the impacts that could lead to a Winter Weather Catastrophe in Atlanta GA would be different than Buffalo, NY. The ability to integrate so many factors to assess what might become a full-blown weather catastrophe is very promising.

For the December 2022 blizzard, was there enough information available for the forecasters and emergency management to convey the potential for a catastrophic winter storm?  Possibly. They did know when the storm would hit, that the storm would produce exceptional snowfall, would last for more than a day, would be accompanied by a long period of strong winds, and occur with rapidly falling temperatures which would lead to an extended period of life-threatening wind chills. However, the format in which they communicated the information was a standard template. All of that information is there, but much of it appears in most Winter Warnings that are issued. 


Fig 27: Winter Storm Warning issued by the National Weather Service office in Buffalo, NY on the afternoon before the blizzard struck. 

With the obvious point of playing Monday morning quarterback, would a statement such as the one below conveyed a better idea of the severity of this storm?

WHAT…A MAJOR BLIZZARD for at least a 2-day period with up to 3 feet of snow. Winds gust to 70 mph Friday and Friday night and over 40 mph through all of Saturday creating whiteout conditions. TRAVEL WILL BE IMPOSSIBLE. Temperatures will become very cold. Along with strong winds this will create life-threatening wind chills to -20° through the 2-day length of the storm. IF YOU ARE STRANDED OUTSIDE, YOU COULD DIE.

WHERE…Niagara, Orleans Genesee and Wyoming counties including Niagara Falls, Medina, Batavia, Buffalo, Orchard Park and Springville

WHEN…The blizzard will strike between 8AM-9AM Friday. Conditions will get bad very quickly. Whiteouts will then occur for the better part of the next 2 days, through all of Saturday MAKING TRAVEL IMPOSSIBLE.

IMPACTS…MAJOR BLIZZARD. TRAVEL WILL BECOME IMPOSSIBLE. Cars and people will become stranded due to whiteouts and roads drifted over with snow. There will also be life-threatening wind chills for the course of the storm. Because this blizzard could last over 2 full days, it will mean if you are stranded outside, YOU COULD DIE. Emergency personnel may not be able to rescue you. This will not be a typical lake-effect snow storm. IT WILL BE MUCH WORSE.  

There will likely be several papers and studies on the impacts of this storm, especially the number of fatalities that occurred. Hopefully this will lead to better communication of the expected impacts that would put a storm like this one well above and beyond the "typical" winter storm. 

Until then, I remember something an old WWII forecast told me when I was training as an intern at the NWS Buffalo office long ago. He said “that any forecast can be the most accurate prognostication, written by the most intelligent PhD, but if you cannot communicate its impacts effectively to the public, it is not worth the piece of paper it’s written on”. There needs to be a better system to highlight what separates a garden variety storm (a.k.a. November 2022 event that produced 3 to 6 ft. of snow) from the truly catastrophic storm such as the Christmas Blizzard of 2022 in Buffalo, NY. 

Tuesday, February 15, 2022

Ice Pillars - The Light Sabers of the Sky


The atmosphere is an amazing creation, and some of the things that go on up there are truly “out of this world”. One that I have been treated to only rarely is something right out of Star Wars. Everyone must be familiar with the light sabers that were part of Jedi Order, and that’s what I am reminded of when I see Ice Pillars in the sky. Click on the video below to get a better idea of how they look in real life. 



Ice pillars, also known as Light Pillars are another one of the amazing optical phenomena that occur in our atmosphere.  The are formed under very special conditions and therefore are quite rare. There are a few ingredients necessary for the formation of Ice Pillars.  You need very cold air temperatures, usually below 15°F, which allows for the formation of ice crystals, hexagonal plates or dendrites that are necessary for the reflection of light rays from the source. Those kinds of temperatures immediately eliminate most of the populated regions of the globe so that it’s a feature normally seen at the higher latitudes of both hemispheres on earth.  Those ice crystals, either fall gently down to the ground or float in the air as you would see in ice fog. In addition, because the crystals need to take on a certain flat configuration in the air and not be jostled about so they can reflect light rays properly, the air needs to be almost still. 


Now once you have all of these conditions in place, how in the world do the pillars of light form? That is where the optics of the atmosphere comes in. Light rays that come off a point source, most commonly street lights, are normally directed up into the sky in all directions. All ice crystals present in the atmosphere reflect the light from the source. But only those crystals that are aligned in a common vertical plane will direct the light towards the observer. If a person is lucky enough and is at the right angle looking back toward the light source, their eyes will see light rays that have been reflected off a column of those perfectly aligned ice crystals. The result is that the eye perceives a column of light above the light source. It is not a real column of light, rather an illusion created by the ice crystals reflecting that light. 


 
Different colored light sources will result in different colored columns in the air. I have seen red light pillars that came off runway lights at an airport as well as train yards. The pillars I saw in these photos came off sodium lamps and they have that eerie, soft yellow glow to them.  


  
Winter is an amazing season. So much of what we experience outdoors can seem other-worldly at times. From beautiful snowflakes to ice needles and rime ice, ribbon ice, ice pillars to the blanket of white that covers the ground, allows for us to ski, skate on frozen water, it truly is a magical season. Keep your eyes open and you can find some of these hidden gems if you take the time to look and explore. Enjoy!!   



Friday, February 12, 2021

Why Portland, OR and Seattle, WA Get Snow and Ice Storms

National Weather Service Winter Alerts Issued Thursday, February 11, 2021 for parts of Washington and Oregon. Note the Blizzard Warning for the tiny area on the map, The Columbia River Gorge.

Rough winter weather is being forecast for the Pacific Northwest. In fact, Blizzard Warnings were issued, not for the mountains, but the Columbia River Gorge only a few miles from Portland.  In Portland and Seattle Winter Storm Warnings were posted. Don't these cities normally just gets clouds and rain in winter?  Yes, for the most part they do, however under specific weather patterns, they can get their share of winter weather.  

I find mountain weather so very interesting. Combine the largest ocean in the world on one side of these Pacific Northwest cities and some of the tallest and snowiest mountains in North America to the east and you get a wonderful natural laboratory to study the weather!

Portland, Oregon and Seattle, Washington are located on the Pacific Northwest Coast in between the warm and moist Pacific Ocean to the west and the towering Cascade Mountains to the east.  Because of their proximity to the coast and their sea level elevation, both cities receive very little in the way of winter weather.  In fact, Portland receives only 4.3 inches of snow annually and Seattle gets just a bit more at 6.8 inches.

You will want to look closely at two features on the map above, The Fraser River Valley in southern British Columbia, Canada up north and the Columbia Rover Gorge in the southern part of the map.  These two geographic features play a big role in wintry weather for Seattle and Portland. 


The biggest reason these two locations do not get much snow is that it is just too warm long the coast to see much in the way of frozen precipitation. Essentially, The Cascades act as a gigantic wall to keep the cold air that comes down out of Canada to the east of the mountains, protecting the West Coast from frequent outbreaks of really cold air.  

Down along the coast, at sea-level there aren’t many ways to get cold enough for snow or ice.  Just east of the coast however, it snows “to beat the band” in the Cascades because higher elevations alone produce a much colder environment, one that is much more favorable for snow.  The temperature drops a little more than 3 degrees for every 1,000 ft. elevation. If you go up 5-10 thousand feet that's a 15 to 30 degree drop in temperature, more than enough in the winter to make snow.  The extra lift created by prevailing westerly onshore winds heading up the slopes of these 10,000+ ft. mountains also wrings out more precipitation from the moisture-laden air. 

It’s crazy when you realize that Seattle is only about 50 miles as the crow flies from Mt Rainier. The mountain tops out at 14,411 ft. and at the Paradise Ranger Station, elevation 5400 ft., they average 639 inches of snow each winter. Back in the winter of 1971-72 they picked up 1,122 inches of snow, a world record at that time, while Seattle averages 6.8" of snow.

Wow!! What a difference 50 miles makes. This may be one of the greatest differences in annual snowfall over such a small distance. 


So, what does it take to get snowfall in locations like Seattle and Portland, its neighbor to the south? Well, you need a way to get cold air across the Cascades and into those coastal areas. A few times each winter season, the large-scale weather pattern sets up to provide a way to get that dense, cold air across the mountains.  Those conditions begin with the presence of an Arctic High Pressure system over western Canada that pushes very cold air down along the east side of the western mountain ranges.


Seattle

In Seattle and locales around the Olympic Peninsula, that cold air can come through gaps in the mountains that are to the east.  Under conditions with strong High Pressure east of the Cascades and Low Pressure just off the Pacific coast, a pressure gradient develops from east to west. The wind wants to blow from high to low pressure, like letting air out of a balloon. The really cold and dense air from east of the Cascades wants to get west, but it’s so dense it is tough to get over the mountains.  However, where there are gaps in the mountains, it offers a perfect gateway for the air to move through, sometimes all the way to the coast.  



The Fraser River Valley, just across the Canadian border in British Columbia serves as a significant gateway for that arctic air to pass through and it is often responsible for pre-conditioning the temperature of the lower atmosphere with cold air to produce snowfall.



Portland

Portland has some of the same characteristics as Seattle, but is located about 100 miles south.  Instead of getting cold air through the Fraser River Outflow, Portland is right at the mouth of the Columbia River, which runs from east to west through the Cascades and down to the coast. 

The gorge is the only near sea level gap through the Cascades. Its average width is about 3 miles at river level.  It stretches 120 miles back to the east and the western entrance is less than 15 miles from Portland.  The crest of the Cascades lies about 45 mi east of Portland.  

One of the most beautiful places in the world in my book, The Columbia River Gorge features some amazing weather, including strong winds that allow for some great wind surfing. In winter, maybe not as inviting.

 



In fact, Portland Oregon gets a majority of its wintry weather when the winds are out of an easterly direction. On a broad sense of course, you would be hard pressed to get snow or ice from the westerly winds coming off that warm ocean.  However, similar to Washington State, a large pressure gradient between arctic air and strong High Pressure to the east of the Cascades and Low pressure off the Pacific Coast results in a flow of cold, dense air from east to west through the gorge.  



The graph below shows, without a doubt, the dependence on wind direction to produce wintry precipitation in Portland.  When the low-level winds are from the east and the mid-level flow is from the west, it becomes the “perfect storm” of sorts for snow or ice.  Snow will occur under conditions when the atmosphere is also cold aloft.  Typically, that comes with closed upper levels “cold-core” Lows.  However, if the air aloft is warm and the easterly gap winds are below freezing, then precipitation formed way up in the clouds in the form of snow melts as it drops through the warmer mid-levels then refreezes as it hits the surface where the temperatures are below the freezing mark. 


The distribution of annual snowfall and freezing rain vs. wind direction clearly shows just how important the role of easterly winds is for wintry weather in Portland, Oregon. 

The soundings below, taken at Salem Oregon, show the difference in the temperature throughout the atmosphere for snow vs. ice events in the Lowlands in Oregon to the west of the mountains including Portland. Notice the above-freezing layer in the sounding on the left, perfect for melting snow which then freezes on contact where surface temperatures are well below freezing. The sounding on the right shows above freezing surface temperatures but the atmosphere quickly cools below freezing a few hundred feet off the ground. That temperature and moisture profile results in heavy, wet snow. 


No, they don’t get too many snowstorms or ice storms in the Pacific Northwest, but they are more common than you might think in places like Seattle and Portland. You just need the proper ingredients to come together in the wrong place at the wrong time, and Voila, you have the recipe for winter weather.