1/17/22

December Was Mild & January Is Cold Like Several Analoges Suggested But Where Is The Snow?? Winter 2021-22 Update

Winter 2021-22 teased us again in November with an early start to winter with above normal snow and below normal temperatures. Suggesting we better hunker down for a long cold and snowy winter but Mom Nature with her bag of atmospheric tricks had other ideas. Even with our snowy November; much of Southeast Lower Michigan is averaging up to around a 1/2 foot below average - and it would be worse if November hadn't had above normal snow. Since the official climatological beginning of winter /Dec/ some areas are approaching a foot below normal snow thus far because of both December and January scant snowfalls. True; just under half of January is yet to unfold but the outlook for any major system through the end of the month is questionable at best. 

Nearly all the potent snow systems have circumnavigated the southern Lakes/Northern Ohio Valley extending from Chicago /less snow than we've had at about 1/2 foot/ to Indianapolis /not even an inch/ to Dayton /a few inches to Detroit /just over a foot with 13.2"/. The only decent snowfall has been lake effect as the cold winds blow across the Great Lakes. The city of Cleveland area has been clipped a few times with East storms but still running a snow deficit near 10" even with today's /17th/ storm. Quite contrary to the normal La Nina precipitation pattern we started with in December.

The winter's analogue temperature pattern was primarily suggested to start off above normal but fall below normal mid to possibly late in the period. The following four analogues best represented many factors but primarily temperatures. Why keep the Winter of 2011-12? It scored high marks for December but never saw the change to cold like the other winters. It still is possible the winter still may average above normal with about 1/2 of it yet to come. It actually was the only winter that averaged above normal (and notably) using my method of just a degree of normal (see Legend below). Normal winter temperature for Detroit is 27.9 degrees. The rest of the 11 analogue winters saw an overwhelming amount of analogues averaging around normal /6/ while 4 averaged below normal (see last column). Thus far with everything considered; the Winters of 1984-85 and 1971-72 are up front in the race but the snow better start flying to put 1984-85 out in front. Snowfall for the Winter of 1984-85 totaled 55.1" whereas the Winter of 1971-72 has the edge as of now with just 29.0" total /snowfall thru 1/17/21 - just 13.2"/.

 










Looking at the latest GFS guidance into the end of January to Groundhog Day plots wave after wave of drier cold air surging from the Arctic Region or central and eastern Canada; spreading into the eastern half of the US. Keeping one eye on the map and the other on the departure scale at the bottom of the loop shows some hefty departures below normal at times. And; these last two weeks of January are normally Southeast Michigan's coldest period of the winter with the daily mean temperature at 25 degrees /normal high lower 30s & lows upper teens/. 

Fortunately; there are some quick moderation trends with surges of milder air ahead of each successive cold shot beginning this week. Undoubtedly this will vary with each run but it does suggest more of the same already seen this January. We are mainly concerned with the trend forecast through the two week period. A few systems should bring snow (possibly even a brief rain) with the best system late in the weekend into early next week. If something outstanding develops in the shorter range; I post on here and FB /Facebook/. The following maps run from Martin Luther King Day /17th/ into Groundhog morning /Feb 2nd/. Don't even ask if he will see his shadow. 😁




Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian