Current Conditions at Sanborn Field

Monday: Mostly sunny. High: 59 

Monday Night: Partly cloudy. Low: 37

Tuesday: Cloudy. Chances of rain possible. High: 57 

Tuesday Night: Cloudy. Chances of rain possible. Low: 37

 

Wednesday: Becoming clear. High: 59

 

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Discussion:
 

It's starting to sound like a broken record as this forecast starts out with above average temperatures. Highs stick to the upper 50's as we move into December, with lows in the upper 30's. A low pressure system moving in over the next few days brings in clouds along with a possible chance of rain for Tuesday and Tuesday night. Rains should stay light, and accumulations should be from trace amounts to around .05". Things begin to clear out on Wednesday, leaving calmer conditions for the rest of the week.

-Cade

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Forecasters: Baker, Cade, Travis

Date Issued: 11/29/21 10:00 PM CST

Technical Discussion:    

Calm and cool conditions will continue to persist with a possibilities of some showers Tuesday into Tuesday night. The primary focus of this period will be a weak short wave followed by a weakening low pressure system forming off of the Rocky Mountains heading east. GFS and NAM both had a questionable path of the low pressure system and short wave, but NAM was chosen due to the NAM ensembles and temperature forecasting.

 High values of divergence were analyzed at 250 hPa allowing for convergence at the surface Tuesday afternoon (18Z). These values stick around through Wednesday afternoon giving suspicion to a possible front moving through, or possible lift at the surface. 

This is again supported as higher levels of spin and lift at 500 hPa are swept into the area moving NW in association with the LPS northeast of the forecast area. However, a short wave moves across the CONUS from the pacific northwest Tuesday at 18Z. 

The area seems to stay quite dry until Tuesday morning as visible on 700 hPa Relative Humidity map. Cloud cover Tuesday into Wednesday will keep temperatures warmer, leading to a potential warm up on Wednesday as high pressure builds back in and winds return to a northwest flow. Along with the LPS moving into the forecast area, the area may see some upper level clouds Monday into Monday afternoon; however, clouds will begin to form ahead of the LPS due to surface winds switching southerly allowing for moisture and WAA to enter the area. This is supported by the moisture train and moisture vectors. Which leads to a suspicion of possible showers Tuesday with the passing of the front.

Surface winds show a weakening LPS moving across the area. Ahead of this, a possible cold front is evident due to the NAM surface map. With WAA bringing in moisture and warmer temperatures Monday afternoon, a possibility of some rain Tuesday into Tuesday afternoon should not be ruled out ahead of the cold front passage. However, with the strong Northwest flow that we have recently seen, conditions have the potential to stay dry. 

As the LPS weakens as it moved west, high pressure will build back in Wednesday, for another clear and quite sunny day bringing temperatures back up into the upper 50s.

-Baker