For much of the United States winter has been full of surprises – southern snow, arctic cold, very mild weather. There hasn’t been much weather we have missed this winter. The good news: we have avoided major catastrophes like floods, ice storms, multiple major winter storms and severe weather, so far.
Breaking down the United States into three areas – East, Midwest and West – let’s quickly look at what meteorological winter (December 1 to February 28) has supplied since December. This is a simple review with a focus on just temperatures and snowfall.
Eastern United States
Figure 1 is an analysis of measured snowfall from December 1 2017 to February 11 2018 and how it compares to the 30 year average (1981-2010) of snowfall of the same time period (Dec 1 to Feb 11). Areas in green are above average when compared to the 30 year average. Light brown and yellow are below average. As you can see, most of New England is above average with a significant area around the eastern Great Lakes well above average for snowfall – western New York and northwestern Pennsylvania. Also, apparent is the below average area of snowfall around Washington DC, Baltimore and Philadelphia that extends south and west into West Virginia. Now, using the same time period, Figure 2 is an analysis of temperatures. Green in Figure 2 denotes below average temperatures. As you can see, most of the eastern United States has experienced slightly below average temperatures, when compared to the 30 year average. The greatest departure is western New York and northwest Pennsylvania. The quick takeaway for the East Coast: winter has been slightly colder than average with most locations, but not all, seeing slightly more snow than normal.
Midwest United States
Using the same time period and scale as with the East, Figures 3 and 4 shifts the analysis to the Midwest. Snowfall distribution looks evenly split with large areas of above and below average snowfall. Above average snowfall is most noticeable in Figure 3 from Detroit west into northwest Indiana. Below average snowfall is most noticeable in the Upper Peninsula of Michigan and western Minnesota. The Figure 4 analysis of temperatures shows that most of the region has experienced slightly below average temperatures. The greatest departure covers northern Wisconsin and northeastern Minnesota. The takeaway for the Midwest: winter has been colder than average with an uneven distribution of snowfall.
Western United States
Analysis now shifts to the western United States. Figure 5 shows large areas of the west with below average snowfall. Only Montana and Wyoming have experienced above average snowfall. The Figure 6 analysis of temperatures shows almost the entire region experiencing above average temperatures. The exception is Montana with below average temperatures. The takeaway for the West: winter has been much warmer and dryer than normal and starkly different from the winter of 2016/2017 – last year.
One More Month of Winter – The Look Ahead
A pattern shift is occurring over the last two weeks of February. This shift favors above average temperatures for the eastern and southern United States with below average temperatures for the western United States – in contrast to what we just looked at above. This favors snow for the western United States and also shifts snow and ice for the eastern United States north along the Canadian border. For northern states in the Midwest and East, expect more rain and rain snow mix with storms before the end of February. Figure 7 is a probability forecast for precipitation. Areas in green have greater than a 33% chance of above average precipitation from February 19 to February 25. That covers most areas east of the Rocky Mountains. Figure 8 is a probability forecast for temperatures. Red is used for areas with above average temperatures expected with blue over below average temperatures. Over the southeast, spring like weather will occur with below average temperatures over the central and northern Rockies and northern plains.
Looking even further ahead, ensemble models favor another pattern shift towards the end of February with the impacts lasting into early March. This shift would bring colder weather back into the central and eastern United States. Another shift really sums up winter for most people east of the Rocky Mountains – a week or two of winter weather followed by a break from the snow and cold. Only to have another shot of cold and snow return. We just never locked into a long term pattern, which is typical.
Even though you may be craving for winter to end and for the snow to melt, or not return, we aren’t there yet. If you live in the Great Lakes and Northeast, after a short break and melt, expect more wintry weather for the end of February and early March. If you live along the Gulf Coast and Southeast Coast, there is a strong chance winter weather is over for you.
Mark McGinnis is a contributing editor and is the owner of Fair skies Consulting.