Winter Synopsis 2013-2014

This winter was cold. That is unquestionable. From a records standpoint this winter stands as one of the coldest in the past 50 years. For Fairfax and the rest of the DMV it was also one of the snowiest, with snow totals well above average. 

Winter snowfall totals for major cities (Accuweather.com)

That being said, with spring officially here, it is time to look back at the winter that was.

Pre-Winter-Temperatures started off relatively average for the most part. The main cooling took place around the time of Thanksgiving break and into December. The first snowstorm, Winter Storm Dion was a relatively weak storm which brought a mix of freezing rain, sleet and snow and of course our first batch of class cancelations. This was of course the first of many snowstorms during winter.

Early Winter: December 21^st-January 20^th- This Winter actually started on a mild note, with the first day of winter actually setting record highs across the region for the first couple of days. This confused many students and baffled even the likes of expert meteorologists. This quickly shifted though as the cold frigid air entered our region early January dropping temperatures into the single digits and dropping our first snow of winter. The lowest temperature of 2.8 degrees recorded on January 7^th was the climax of this cold spell.

Well below average for much of the month of January (Washington Post)

Mid Winter: January 21^st –February 20^th-The cold below average air started to take hold of the region. The bitter cold due to the arctic front set records and created situations with dangerously cold wind chills. On January 23^rd, a low of -2.7 degrees F was the lowest recorded temperature in the area in over 100 years. The cold stretch from the 22^nd-29^th produced lows in the single digits or lower for 8 straight nights. Temperatures were more seasonable into February. Our first major snow event happens with Winter Storm Pax which brought upwards of 6-10 inches for the entire region and a second round of school closings.

Runners enjoy serenity of empty streets during Winter Storm Pax

Satellite image of Winter Storm Pax

Late Winter: Febuary 21^st-March 20^th-Though this period started with some needed relief and even some days of above average temperatures; this quickly changed, with below 0 temperatures returning in early March. This followed quickly by Winter Storm Titan, a strong storm that brought an array of rain, freezing rain, sleet and eventually snow. Finally, winter wrapped up with an unexpected twist with almost a foot of snow on St. Patrick’s Day, breaking previous records for the day. This of course was not the end of the winter temperatures or snow.

Snow totals for the late and unexpected St. Patrick's Day snowstorm (NOAA)

Post-Winter: March 21^st-April 10^th- Just because spring has started, does not mean temperatures will rise on command. Especially with a cold air sustaining itself across much of the nation’s heartland, it has taken a bit for temperatures to rise. Finally though, it looks as if spring is here to truly stay.

Here are some questions about this winter I want to help answer:

Why was this winter so long and cold?!

Normal Daily Average and Actual Average trend lines (Washington Post)

This is the question that most people had as there was little doubt that this winter was one of the roughest when it came to the sure amount of frigid days and days with frozen precipitation present. It started out with a welcoming presence but soon almost the entirety of students became weary of the cold and yearned for warmer days of spring.

The answer lies surprisingly enough with the global climate change that has transfixed the entire atmospheric science and meteorology fields. Specifically the warming ice sheets of the Arctic played a pivotal role with the overall dip of cold air across the region.

Think of the North America not by region, but by large air masses. These air masses interact with one another all of the time, and produce the weather we all know. These air masses range in temperature (Tropical-Warm, Polar-Cold, Arctic-Frigid) and by location (Maritime-Ocean, Continental-Inland). Why this is important is that with the warming of the Arctic, these air masses will play a large role in huge temperature shifts. During the winter months, the tropical air mass shrinks and is confined to farthest Southeastern regions of the country while the polar and arctic air masses move southward. This winter, the Polar and Arctic air masses moved farther south than normal, which caused temperatures to free-fall across almost the entirety of the nation.

The Cold Air Mass moves south and eastward from its source region in central Canada

How this occurs is a fairly complicated process physically. Conceptually though, it is fairly easy to understand. The Arctic is warming at a fairly high rate. This is due to the fact that greenhouse emissions are being released into the atmosphere. What happens after they are released into the atmosphere is not a mystery either. The greenhouse gas for the most part does not stay in one location. Instead of staying dormant, it travels through the various canals and streams in the ocean sinks and upper-atmosphere upwards towards the poles as part of the heat transfer process; the basic process that keeps the equator from getting too hot, and poles too cold. A vast majority though stays within the Arctic, and through a positive feedback process, has melted a vast majority of the ice sheets and warmed the average temperature dramatically.

What does that mean for us?

-More than you would quite think. The jet stream is the upper-level air-flow at the top of the troposphere. It is caused by the planets rotation and temperature and pressure differentials between the arctic, polar and tropical regions and plays a large part with weather. A dip in the jet stream across our region could mean drastically colder temperatures and a ridge in the jet stream could mean tropical, humid air. With the warming Arctic, the jet stream has weakened due to the lack of temperature differential and corresponding pressure differentials of the upper atmosphere. This weakening has caused it to ‘meander’ which means larger dips and ridges. This along with the process of “blocking highs” which helps sustain a dip in the jet stream for long periods of time created a perfect storm for frigid conditions for several weeks during the heart of winter. The overall weather pattern also was affected during this time, creating almost a conveyor belt system of storm development bringing winter storm after storm across the middle of the county and into our region.

Jet Stream pattern for much of the winter. Notice the large dip towards the middle of the country, and the East South-Easterly winds bringing abundant moisture across the Midwest and Mid-Atlantic regions. (climatestate.com)

Were there other reasons other than the warming Arctic?

El Nino might have also played an important role as well in keeping this winter cold and wet. El Nino is a process of warming the waters across the Eastern Pacific ocean and the coinciding atmosphere to produce weakened trade winds and lower atmospheric pressure of the region. This process alone has momentous affects on the regional climate of North America. During an El Nino year, it is said that the winters of the Southeastern United States are cooler and wetter than normal years, while the Southwest is warmer and drier than normal. This March was the coldest and snowiest on record.

This shows the conditions present during an El Nino winter such as this year (NOAA)

This winter was actually very warm on average for this very reason in Alaska, which saw a very large ridge over a majority of the country for a large part of the winter. Weather is a all-encompassing concept, one thing directly affects another.

Will this mean that we will have a warm/hot spring and summer?

-To the best of my knowledge, I think it will be a relatively average this spring and summer with of course the normal amount of variations and anomalies. Even with the impacts of the possible El Nino this year, the climate forecast for this spring seems to point to average to slightly below average temperatures through the spring months.

The summer on the other hand is a little more hazy, as it is farther out on the time scale. 

There is an expected to be a large delay on severe weather events for the area this spring and early summer due to the lingering effects of the harsh winter. 

Severe Weather Climate forecast for this Spring/Summer 2014

Will more winters be like this?

-Again a hard question to answer, and one where a simple answer of yes or no might not be the best of responses. With the looming climate change, we can definitely expect a new set of rules for seasonal patterns. To keep it simple, yes there will be more like this, but in the immediate future the likelihood is highly doubtful for a winter in the next couple of years to be this harsh.

We at Forecast GMU enjoyed this winter as it brought us ample opportunities to give you sufficient detailed forecasts and vital information on the incoming winter storms and systems that directly impacted our area.  We always enjoy your feedback as we look forward to warmer temperatures and the end of an academic school year.

What are some of your questions about this winter? What were your favorite memories? 

Share them in the comments below or message Katie, Nick, or me with your questions.

-James