Thursday, February 13, 2020

Current Conditions at Sanborn Field

 
 
Thursday Night - Clear. Low: 2-6


 
Friday- Sunny. High: 28-32 
 


Friday Night - Clear. Low: 22-26

 
 
 
Saturday - Overcast. High: 46-50



Sunday - Clear. High: 50-54


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Discussion: 
Following last night's cold front, we expect clouds to clear out as high pressure sets in. Tonight will be bitterly cold as it is the first clear night after a cold front. However, this weekend will have a general warming trend as warm air moves in from the southwest. High pressure will ensure mostly clear skies except for Saturday where there will be just enough moisture to provide a greater amount of cloud cover.
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Forecasters: Lieberman, Dowell, Ritter
Issued:  5:00pm: February 13, 2020

Technical Discussion (The nerdy stuff we are discussing in class) 
We used primarily the GFS supplemented with NAM soundings and SREF plumes. The WPC recommends a general model blend trending toward the GFS and NAM. At 250MB, a jet max is located over Maine and southeast Canada. This places Columbia well within the left entrance region, indicating higher chances for divergence aloft. At 500MB a positively oriented trough extends from the Great Lakes to western Kansas. At 700MB moisture has cleared out from last night and we are left with northwesterly winds. Moving down to 850MB, we see zonal flow and extremely cold temperature profiles throughout the central CONUS. At the surface, an area of high pressure is centered over the eastern Nebraska-South Dakota border. This anti-cyclone is causing northerly winds in Columbia currently.

The trough is expected to pass over mid-MO late tonight going into early tomorrow morning. Despite rotational energy associated with this feature, a general lack of moisture and forecasted lift leave no concern for precipitation. However, aloft, the trough will bring northerly winds and CAA. Moreover, the high pressure system at the surface will continue to bring northeasterly winds and CAA as well. This, combined with tonight being the first clear night after cold FROPA means that it will be exceptionally cold.

Friday, clear skies and radiational heating will bring air temperatures up to near freezing. With relatively no moisture in the area, cloud cover will be minimal or non-existent. Winds will be minimal as the center of the anti-cyclone passes just north of Columbia. Late Friday evening,  CAA will begin to transition to WAA as the anti-cyclone travels downstream, bringing southwesterly winds and creating solenoids.

This will continue overnight Friday into Saturday bringing warmer temperatures. Moisture will also be advected into the area bringing cloud cover. Friday night will therefore be substantially warmer than Thursday night and this trend will continue into Saturday as moisture and WAA persist and Columbia will see unseasonably warm temperatures.

Moisture will clear out Saturday night bringing clear skies on Sunday. This combined with minimal winds will bring slightly warmer temperatures than Saturday. Future forecasters should monitor the possibility for persistent moisture and cloud cover.



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