Current Conditions at Sanborn Field

Tonight - Clear skies  Low: 10-14

 
Saturday - Mostly sunny with increasing clouds in late afternoon. High: 32-36

Saturday night - Mostly Cloudy Low: 25-29

Sunday - Snow changing to winter mix High 30-34

Monday -  Morning winter mix changing to rain High: 36-40

 

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Discussion:  

Another extremely cold night, before we warm up. The lack of cloud cover tonight into tomorrow morning will prevent warmer temperatures from being caught near the surface. Saturday looks to be a not so pleasant sunny day due to the cold high temperatures. The coming of warm and moist air during the afternoon will support the cloud formation. Finally, Sunday conditions will bring some different type of precipitation, but the precipitation type on Sunday and Monday will depend on our temperatures warming near freezing.

 

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Forecasters: Johnston,Rojas, Sumrall & Hirsch

Issued: 4:46 p.m., February 8, 2019

Technical Discussion (The nerdy stuff we are discussing in class!)

The current partly cloudy skies will clear over night as the high pressure system will remain over the region until Saturday morning.

The situation over the area based on GFS shows a shift in the Northwesterly winds to more southwesterly flow at 12Z on Saturday. That WAA is a result of the short wave development in the upper level which will drag sufficient moisture to the middle level, as the lower level remain dry at 18Z on Saturday. That is when some cloudiness will start to appear. The column will moist gradually until enough vertical velocity appears in the lower level (-8ubar/s) at 9Z on Sunday (3:00 am CST) and the 09Z GFS sounding supports as well. It moistens all the way to the surface starting at 12Z and with the temperature being below freezing, precip is expected to start as snow. A warm nose is present at the 15Z indicating a possiblity of wintery mix. The persistent southerly flow will support that veering aloft toward Monday morning where similar conditions are recognized. 
Precipitation type fo Sunday into Monday will vary between rain or winter mix due the the GFS soundings surface temperatures staying near freezing or just above from 21Z to 18Z Monday. What precip we get will depend on the location of the 540 line. The GFS keeps us just south of the line, leading to why we leaned towards a mix, before eventually warming up to a change over to rain.