Current Conditions at Sanborn Field

 

 

Friday: Cloudy. High: 43

      
 

Friday Night: Increasing Mid and Upper Level Clouds. Low: 32

 

Saturday: Rainy and windy. High: 44

    

Saturday Night: Rain ending around 10pm to 2am. Low: 36

 

Sunday: Few Clouds. High: 50

 

  

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Discussion:

This weekend our temperatures range from the the low 30s to low 50s. Friday we are going to have increased clouds. On Saturday rain begins in the mid-morning and continues until around midnight. Sunday temperatures in increase as the sky clears up. Don't forget to reset your clocks to spring forward one hour on Sunday after the time changes at 2:00am.

- Allen

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Forecasters: Sallot, Allen, Mcguire

Date Issued: 03/010/2023 10:20 AM CST

Technical Discussion:

 

The main concern of this forecast is the precipitation all day on Saturday and Saturday night into Sunday.


As a low pressure system moves to east into the Great Lakes region, high pressure builds in behind it. As such, a ridge is present over the forecast area on Friday, bringing north, northwest upper level flow until about Saturday 9z. This ridge is in between two low pressure systems, one to the east and one to west. The low pressure system to the west will be the main driver of the precipitation on Saturday.


The western low pressure system tracks along the northern US border, and brings a brief period of southwesterly flow in the upper levels around Saturday 21z, before the jet stream becomes more zonal after Sunday 15z through the end of the forecast period.


At 500mb, as the low pressure system moves from MT into ND, vorticity advects into the forecast area Saturday 9z to 12z. This vorticity will help support the formation of precipitation on Saturday.


Additionally, upward vertical motion at 700mb is expected in the forecast area on Saturday around 3z to Sunday 6z, as the trough axis passes through the forecast area. This upward motion coupled with plentiful moisture Saturday 12z to Sunday 6z, further supports precipitation on Saturday into Sunday.


As the low pressure system in the Great Lakes continues east, it encourages northerly flow in the lower levels in MO on Friday until Saturday 00z until the low pressure system in the Dakotas begins to take over - bringing southerly flow to the forecast area on Saturday. As the low pressure continues to move east, into MN by Sunday around 6z, northerly flow in the lower levels return to the forecast area until the end of the forecast period.


A strong LLJ, peaking around 45 kts in northern AR and southern MO on Saturday 21z, which may lead to windy conditions on Saturday.


We expect rain as the precipitation type on Saturday, due to surface and ground temperature remaining above freezing for the entire forecast period and due to a warm near surface layer which will melt any frozen precip. However, the 5400m line runs through central MO and very close to Columbia, the next forecasting shift should watch for any shifts in this freezing line as it may impact precip type.


For precip accumulation, we are expecting between 0.25 in and 0.5 in over the course of Saturday around 12z to Sunday around 6z.

 

Sallot