Current Conditions at Sanborn Field

Tuesday Night: Becoming Partly Cloudy. Low: 51
 

Wednesday: Cloudy and Windy. Rain beginning late afternoon/early evening. High: 62
 

Wednesday Night: Cloudy. Rain. Low: 32
 

Thursday: Overcast. Rain transitioning to wintry mixture early. A transition to snow later in the afternoon. Temperatures falling throughout the day. High: 32

Thursday Night: Clearing overnight. Precipitation ending. Low: 8

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Discussion:

 

Make sure to enjoy the warm and spring-like weather while it lasts! A much colder and wetter weather pattern is expected for the middle of the week. A high temperature in the lower 60s and an overcast sky is expected on Wednesday along with winds upwards of 15 knots. A low pressure system approaching from the southwest will bring rain starting late afternoon early evening on Wednesday. Rain accumulations will be between 0.5 and 1 inch by Wednesday night. Isolated thunderstorms are also a possibility Wednesday evening and overnight. Temperatures will drop going into Thursday morning after the passage of a strong cold front around 11pm Wednesday night. The high temperature will be in the morning, Thursday, as falling temperatures will lead to a transition from rain to a wintry mix around 6am and a change over to snow late Thursday afternoon. Total snow accumulations are uncertain at this time, due to the timing of the change from a mixture to snow. Any precipitation will end Thursday night but temperatures will continue to fall, leading to a very cold low on Friday morning. 

 

- Duff

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Forecasters: Alexander, Duff, Orr

Date Issued: 2/15/2022 5:00PM CST

Technical Discussion: 

 


What a beautiful day Tuesday has been! Unfortunately, this mild, warm weather is about to get interrupted. There is a low pressure system and trough working its way towards the Mid-Mississippi Valley which will bring rain, sleet, and possibly snow. Due to the continuity of the GFS between runs, we used it for our deterministic model. We also used the NAM NEST for convective aspects and consulted the NBM for temperatures and precipitation type. There is a lot of uncertainty in the chance of snow in this forecast.

Currently, Mid-Missouri is experiencing a clear sky and southerly winds, keeping us about 20 degrees above seasonal averages for February. There is a trough beginning to traverse the CONUS, moving east, from the Rockies; this will be the driving force in the active weather later in the week.

Into the overnight hours Tuesday, the low level jet will begin shoving moisture into the region at the 850mb level down to the surface. The winds are expected to be around 15-20 kts from the south. These winds will persist until Wednesday night when the cold front will pass over the area at about 05Z. Wednesday will see clouds moving in from the southwest. The upper levels start getting organized for the upcoming event as the jet stream at 250mb begins picking up speed, and creating more divergence aloft. This divergence will assist in the formation of precipitation in the evening hours of Wednesday and continue overnight. By the time the sun has set Wednesday, rain will be falling and there is a chance of isolated thunderstorms. CAPE values look to reach 500 J/kg over Columbia, and there will be isolated cells of strong vorticity at this time spread across the region, as well. There will be strong, widespread divergence aloft with jet stream speeds in excess of 140 kts. Moisture will continue to be pulled into the area by the LLJ until the early morning hours of Thursday, after which it gets pushed to the east by the low pressure system and corresponding cold front. Precipitation total for Wednesday night will be between .5 and 1 inch of rain. Also, the precipitation type is expected to remain rain until Thursday morning.

As mentioned before, the cold front is expected to pass over Columbia just before 06Z Thursday. This cold front will cause a midnight high temperature, winds to shift northerly at 10-20 kts, and cause mixed precipitation to occur Thursday morning. At or slightly after 12Z, the precipitation type is expected to become a mix of freezing rain and sleet; this P-type will continue throughout the day. The winds are expected to calm down early in the day, down to about 5 kts, but will still cause us to start the day off at 32F and end the day in the mid-20's. At the upper level, the widespread divergence will be leaving to the northeast during Thursday as the jet stream forces it downstream. There will be a strong line of vorticity that traverses the area about 15Z. This could cause an increase in the rate of precipitation, leading to faster and larger accumulations. We expect to see .5 to 1 inch of winter precipitation on Thursday.

Thursday night, there is a chance for snow to occur around 18Z, however, there are shallow dry layers layered between saturated layers with the environmental temperature line hovering around freezing in the low-mid levels. This is causing uncertainty about if snow will form, if it will reach the ground, or if it will remain a wintry mix until the precipitation stops. At this time, snow totals are expected to be less than an inch.

-Alexander