Tuesday, February 9, 2021

Wintery 10 days coming up- can we do better than mostly ice?

 We have a fun, fascinating pattern setting up where a piece of the polar vortex will position itself over the upper Midwest. (Great for Cold)

We also have a Southeast ridge based on other issues in the pattern ( Leads to warmth for the southeast) We sit in the Northern part of the south, tucked in near the Blue Ridge and quite honestly, the next 10 days will be chaotic. 2-4 chances of winter precipitation(and rain) We could see 2-3 inches of liquid in that time frame and trying to separate what falls when and where will be a challenge. 


Event 1 2-11/12. Cold air sinks in from the North, rain changes to freezing rain then sleet and perhaps snow. In general the further north you go the more sleet and snow you see. This likely won't be a big snow maker but 15 miles may be the difference between 3inches  of a sleet snow mix and a half inch of freezing rain. 

* I think the kids are out of school regardless most places Friday and maybe even Thursday*


Event 2 possible as early as 2/13 or Saturday as another weaker wave drops some light freezing rain during the day Saturday. 


Event 3 has the potential to be the worst of the three. This would be on or about February 16th.  The cold air REALLY builds in at the surface and some data suggests an ice storm that starts while temps are below 20. This would be Monday into Tuesday time Frame.  This is just one plausible outcome, but isn't the forecasted outcome at this time.  Liquid amounts of over an inch with temps in the teens rising towards freezing has BIG TICKET written all over it. 


This is a map of the heights anomalies. In simple terms, heights are calculated by the average temperature below that level. Those area blue and purple along the Canadian border and much lower than normal heights, meaning COLDER than normal temperatures. (Actually a piece of the polar vortex is there) The red over the Southeast USA is higher heights, or what should be warmer than normal temperatures.  

This gradient between higher heights and lower heights is creating all these storms. Cold air likes to push south in this pattern but is being pushed back by the Southeast Ridge. If that ridge wasn't there, we'd be cold and dry and that meaning very cold.  If that colder anomaly was not there, we'd be rather warm. What makes our situation unique is the Blue Ridge Mountains where the cold air, which is heavy and dense gets trapped and can't be moved out. (Remember, cold heavy- warm, lighter)  Some of the data for our storm Tuesday has surface temps in the teens but 5000 feet above temps are in the 40's. For those who remember the ice storms of 1994, this pattern is not far off looking 6-7 days out. 


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