Thursday, February 9, 2023

 

 



Thursday:
Decreasing clouds to sunny conditions. High: 51



 
Thursday Night: Clear. Low: 32

 


Friday: 
Sunny. High: 37

 

 
Friday Night: Partly Cloudy. Low:26
 
 
 


 Saturday
:
Partly Cloudy. High: 46


 

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Discussion: 

Currently we are still experiencing some light drizzle over Columbia, but thankfully, precipitation is expected to stop leading to gradual clearing and sunny skies in the afternoon. Friday will bring breezy conditions with cooler than average temperatures before lovely warmer weather arrives this weekend!

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Forecasters:Hefner, Macko, and Samson

Date Issued: 2/9/2023 10:30 AM CST

Technical Discussion:


Our problem of the day: ongoing saturation will continue to support light precipitation until Friday. For this forecasting period, the GFS20 model was favored over the NAM12 due to its stronger handling of moisture and the current state of the atmosphere.

Currently we are still under the  effects of a baroclinic leaf stemmed from a mid-Latitude cyclone centered over the Great Lakes region. At the time of our forecasting period, surface observations from Sanborn field reports the event has produced 0.78 inches of rain and westerly shifted winds. The mid-Latitude cyclone affecting our region has begun to occlude suggesting the system has reached the mature phase and will start to weaken out over the Ohio River Valley.

Upper air analysis of the 300mb revealed a positively tilted trough due west of Columbia over the Great Plains. This trough will shift down into the Oklahoma/Texas panhandle at 15Z Friday and will begin to deteriorate as it passes over the Mississippi river valley. Deterioration will last throughout the forecasting period. The majority of the active weather brought in by this trough will affect the southeastern United States.

Around the 500mb, positive vort. maxes will hover over Columbia in association with the baroclinic leaf then will roll out into the northwestern portion of the Ohio River Valley at 18Z on Thursday. For the remainder of our forecasting period the only significant amount of positive vorticity will be in conjunction with the trough at the 300mb level, starting at 18Z Saturday and going for the rest of the forecasting period. This will primarily affect the southeastern United States.

Down at the 700mb level there is high saturation (about 90-100% relative humidity values) over Columbia on Thursday, which the majority of the saturation will follow the same path as the positive vorticity at the 500mb level into the northwestern Ohio River Valley. However, there will be a small band of saturation over Columbia overnight Thursday and into Friday morning, going southward and out of our area at 15Z Friday. Skew-T soundings agree with this model as they show saturation occurring from 03Z until around 18Z Friday where the atmosphere becomes dry. It is important to note that the soundings show only shallow saturation. Flurries therefore can be expected and light rain/drizzle during Friday morning. However, due to surface temperatures being above freezing, any precipitation that reaches the ground should melt and not accumulate, expect minimal but not major road condition impacts. For the rest of the forecasting period dry air is expected, so sunny skies. Additionally at the 700mb level, high negative Omega values as well as noticeable positive geometric vertical velocity (GVV) will be over Columbia until 15Z Thursday. Then the negative Omega and positive GVV will move out with the baroclinic leaf system as well.

 At the 850mb level, GFS20 resolves significant wind values over Columbia (~25 to 35 kts) until 00Z Friday where it will, like many of the previous features, continue moving with the mid-Latitude cyclone.

Rounding things out at the surface level, winds will shift from westerly flow to northwesterly overnight Thursday bringing in CAA for Friday, lowering our high temperature on Friday into the thirties. Then overnight Friday a warm front will pass through bringing southerly winds, raising our high for Saturday in the upper forties. The National Blend of Models as well as SREF plumes agree with these temperature predictions.

Notes for future forecasters:

There is a trough over the southwestern United States that is moving closer to our area. Attention should be given for how this will start to affect the Columbia area; however, it is still a ways out from here. Additionally, it is worth checking for future shifts a potential for a seeder-feeder event on a mesoscale level for Friday morning.

-Hefner and Samson



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