A warm up is finally on its way to southeast Michigan

This winter has been pretty cold thus far and yesterday was the coldest day of the year.  The high yesterday was only 16°F and the low was an impressive -5°F, giving us an average of only 6°F for the day!  That is 20 degrees below the average for February 10^th, which by the way was the furthest we have been below average all winter.  So far this winter…

December – 3.7°F below average with 23/31 days below average

January – 2.4°F below average with 20/31 days below average

February – 7.8°F below average with 8/10 days below average (as of Feb 10^th)

Combined – 3.7°F below average with 51/72 days below average (as of Feb 10^th)

This means that 70.8% of this winter has been below average so far!  It is worth noting that the daily average isn’t just taking the high temperature for the day but instead takes an average based on the high and low temperature.  For example, if the high was 20°F and the low was 10°F, then the average for the day would be (20+10) = 30 / 2 = 15°F.

The good news is that the pattern will be changing and we can expect a pretty big warm up on the way.  The first image below represents the current 500mb height/anomaly pattern (500mb is roughly 18,000ft up in the atmosphere) for North America.  The eastern half of the U.S. is under a trough which causes the heights to be lower than average (represented by the blue).  This set up allows for cold arctic air to drop down from Canada which is what we have been experiencing for a lot of this winter.  The second image represents the forecasted 500mb height/anomaly pattern for Wednesday of next week.  As you can see, the pattern looks much different than the first image with the trough now to our east over the Atlantic Ocean and the ridge that was over the west coast states in the first image is now over the eastern half of the U.S.  This ridge will give us higher than normal heights (represented by the orange) and thus warmer weather due to the winds coming from the southwest as opposed to the northwest with trough.

Images courtesy of PSU ewall

So what can we expect?  Temperatures are forecasted to climb into the low 30s during the weekend, to the mid 30s during the first half of next week and possibly into the 40s during the second half of next week.  Some people are forecasting highs in the mid 40s by late next week, but we’ll have to wait and see if it will actually happen.  I have noticed over the years that the first few warm ups of the winter usually come much slower than forecasted.  In regards to precipitation, we have a couple opportunities for snow and rain.  The chances for snow will come overnight as we will be clipped by a passing cold front.  We won’t have much in the way of accumulation from this system.  After that the next chance will be Sunday evening into Monday morning as a decently strong system will make its way out of Canada and into the Great Lakes region.  This system could have the strength to produce several inches of snow except for the fact that it will be deprived of moisture.  In fact, the model runs are showing it to be so much deprived of moisture that we might not get much more than a dusting.  I’ll monitor this system for any significant changes.  After that it looks like there is a chance for rain showers a few days during the week.

Enjoy the warmer temperatures!