Wednesday, January 30, 2019


Tonight - Light flurries early, becoming mostly cloudy.  Low: 4-8.

Thursday - Mostly cloudy.  High: 28-32.

Thursday Night - Mostly cloudy. Low: 26-30

Friday -  Mostly cloudy. High: 40-44.

Saturday -  Mostly cloudy. High: 54-58.

Thanks to for the icons!

After a frigid day in mid-Missouri a warming trend is in sight. Before we warm up, we have a shot at light accumulating snow tonight. Accumulation will be light with about half an inch expected, just enough to coat the ground. Snow will end between 8-10 pm. We remain bitterly cold throughout the day Wednesday but begin the process of warming up Thursday, with temperatures continuing to climb through the weekend. We will finally be above freezing again Thursday night into Friday morning. There is plenty of moisture in the atmosphere that will linger through the weekend providing the cloud cover that persists through our forecast period. There is a slight chance for some form precipitation late Thursday night but little to no accumulation is expected.

Forecasters: Bongard and Sumrall
Issued: 2:37 p.m., January 30, 2019

Technical Discussion (The nerdy stuff we are discussing in class!) 

For the rest of today the frigid temperatures will continue as the arctic air mass that has seeped into the eastern two-thirds of the CONUS continues to keep temperatures dangerously cold. Overnight lows will maintain a single digit status though not quite as cold as the previous nights lows thanks to the air mass heading a bit further east. Skew-Ts show moisture from 850 till 500 mb with omega maximized over this depth. This will allow for light snow fall early on with drying occurring around 09 Z.  Thursday will begin a much needed warming trend as both NAM and GFS model charts depict the broad upper level ridge over the western CONUS propagating into the central Plains pushing the arctic air mass and the trough responsible for its inclusion into the Lower 48 further east. While upper air flow will maintain a northwesterly flow in the upstream portion of the ridge, low level winds will swing around to the south. This is in response to a cut off low that forms over the Four Corners region that will trek into the north Texas by the end of the day Thursday. The eastern flank of this system will help to swing those winds to a southerly course and provide enough warm air advection to get the region above freezing by Friday morning. Highs Friday afternoon should reach into the low 40's with even warmer highs Saturday afternoon as winters cold air gets trapped north of the ridging flow to the regions north.

A shortwave traversing the flow to our north will interact with some moisture advection from the oncoming low pressure system that NAM predicts will create some precipitation development Thursday evening and night. Some of this precipitation may be in the form of freezing rain as temperatures will not be warm enough to be only liquid form. SREF plumes are promoting a greater than 50% chance of snow with around 0.5 inches of accumulation between 00Z and 06Z Friday. GFS on the contrary is promoting only extremely low level moisture and therefore only clouds. Model disagreement this late into the forecasting process makes giving real credence to precipitation chances difficult though a passing shower or even light icing is not out of the question. As the low pressure system passes to the south of the region Saturday morning and afternoon shower activity over the region can be expected though the bulk of the precipitation shield associated with this frontal system will be to the southeast of Missouri. This will be the extent of precipitation chances for the forecast period. 

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