Current Conditions at Sanborn Field

Tuesday night: Wintry mix beginning around 9 P.M. Transitioning to all snow during the early morning hours. Low: 32

 

Wednesday: Snow ending in the late morning/early afternoon. High: 35

 

 

 

Wednesday Night: Mostly cloudy. Low: 22

 

Thursday: Partly Sunny. High: 30

Thursday Night: Partly cloudy. Low: 23

 

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Discussion:

Let it snow! Let it snow! Let it snow! Tonight around 8 PM it will start to rain as a low pressure system moves through the bootheel. Temperatures will drop rapidly into the low 30's and then rain will turn to snow by late evening and continuing throughout the night. The morning commute will be wet and slow as the snow continues to fall into the late morning/early afternoon. 2-3 inches are expected here in Columbia with areas south getting potentially higher numbers. Temperatures after the system moves through will have highs hovering around the low 30's and lows hovering around the low 20's.

-Smitty

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Forecasters: McCormack, Peine, Smith

Date Issued: 1/24/2023 5:00 PM CST

Technical Discussion:

 

The majority of this forecast discussion is focused on the impending winter weather system. A blend of both the 18Z GFS and 18Z NAM were utilized for our forecast due to their accurate depiction on the current location of the impending and impactful surface low pressure system. There is good consensus between the two models in regards to temperatures, precipitation timing, and type of precipitation. The problem for the forecast period is how quickly the rain will changeover to snow tonight, and how much snow will melt due to the ground temperatures currently in the upper 30s.

Here are some key messages for the impending winter weather system:

1. Precipitation is expected to begin around 01Z-03Z tonight, and will likely start as rain and quickly changeover to snow as wetbulbing and dynamic cooling occur. Most of the area should be experiencing all snow by 06Z with the majority of the accumulation expected to occur between 06Z-12Z Wednesday morning. We expect Columbia to end up with 1-3 inches of snowfall before the snow exits the region around 18Z Wednesday.

2. The Wednesday morning commute will likely be impacted due to slushy/snow covered roads that will create slick road conditions. Once the snowfall ends, roads should improve quickly due to the warm ground temperatures and highs expected to be in the mid 30s on Wednesday. A Winter Weather Advisory goes into effect at 03Z tonight and ends at 00Z Thursday for Columbia.

Currently, at 250mb, a highly amplified upper-level trough is ejecting out of the Intermountain West and into the Southern Plains. Within the upper-level trough lies a very strong jet streak located over our region that is providing an abundance of upstream divergence aloft, which in turn is allowing the aforementioned surface low to deepen rapidly. At 500mb, the vorticity maximum associated with the low pressure system is very apparent over Central Texas. At 700mb and 850mb, moisture is currently present due to the southerly flow that has allowed for moisture advection and resulted in the cloud cover seen today.

At the surface, the impending low pressure system will lift northeast out of Texas and pass over the Missouri Bootheel into southern Illinois on Wednesday morning. As this occurs, the strongest frontogenetic forcing and vorticity maximum will stay well to the southeast of our region, keeping the heaviest snowfall rates and highest snow totals over southern Missouri. A deformation band could potentially set up late Wednesday morning as the low pressure system departs, but the majority of models show this band setting up just to our north, which is why snow is expected to exit Columbia by 18Z Wednesday.

A shortwave is expected to ride the northwest flow across the region on Wednesday night into Thursday morning. If enough moisture is present in the atmosphere as the shortwave passes by, a few flurries cannot be ruled out overnight Wednesday. Regardless, cloud cover will continue to dominate over the region until Thursday afternoon when we may see a few breaks in the cloud cover. High temperatures will remain slightly below average (Avg. High:40) for the remainder of the forecast period as we will be under persistent northwest flow.

As the active weather pattern continues, future forecasters should monitor the potential for another shortwave to ride the northwest flow across the region on Friday morning, as it could bring precipitation chances back into the region.

 

- Peine