Friday Night: Thunderstorms early, then mostly clear. Low: 51
Saturday: Mostly cloudy. High: 60
Saturday Night: Decreasing clouds. Low: 33
Sunday: Mostly sunny. High:49
Sunday Night: Clear. Low: 34

 GENERAL DISCUSSION
Severe storms are poised to roll through the forecast area within the next hour as of the publication of this discussion. Wind will present the highest threat, with gusts of over 80 mph expected. Storms will mainly be confined to the single broken line sweeping through the state, with the possibility for embedded tornadoes. Ensure you have a plan in place and a safe sheltering location selected in the event of a tornado warning. Select an interior, windowless room on the lowest level of the building.

-Collier
=================================================================================
Forecasters: Scheerer, Schwent, Collier

Date Issued: 03/14/2025 5:30 PM CDT  

KEY MESSAGES

– A dangerous severe weather outbreak is underway in Missouri. Storms are expected to roll in between 5 and 7 PM.
– Wind gusts exceeding 80mph are the main threat, but tornadoes must not be ruled out.
– Cooling temperatures are expected over the weekend.

TECHNICAL DISCUSSION

A very volatile atmosphere will be present throughout the rest of Friday as a strong low pressure system approaches. A shortwave trough accompanied with the low will move through the state, leading to the atmosphere becoming more unstable throughout the column. With the destabilized atmosphere, copious amounts of vorticity will be brought by the low pressure system, leading to enhanced development of thunderstorms throughout the afternoon, which we are currently seeing (as of 21:30z) in western and south-western Missouri. We are currently dry here in mid-Missouri, however winds will back to the south, leading to strong moisture advection. Omega values, brought by the frontal boundary, are sufficient enough for thunderstorm development as well throughout the evening. The low level jet is expected to be strong throughout the evening hours, which will lead to the strong moisture advection and the increase of vertical wind shear.

The overall storm mode is expected to be a broken line of supercell thunderstorms. This is due to the low level jet allowing air parcels to lift into the atmosphere. However, what is keeping these supercells from being discrete is the moisture pooling along the frontal boundary. If there was more widespread moisture, then the forecast area could see more discrete supercells. In terms of the strength of these storms, they are expected to be severe throughout the rest of tonight. In the 22z sounding from the HRRR, the sounding takes on an inverted v shape, leading to strong thunderstorm downdrafts and high winds at the surface. Surface CAPE values, according to the HRRR, are near 670 J/Kg at 22z which is enough energy to support strong thunderstorms as they enter into the Columbia/Jefferson City area. However, CAPE for severe thunderstorms would typically be greater than 2,000 J/Kg. With the hodograph sounding, winds don’t veer with height as much, which could lead to less spin for storms to become tornadic here in Columbia. As for In the next sounding at 23z, strong moisture advection will become prevalent, as dew points rise from 47 F to 51 F introducing more moisture for these thunderstorms to strengthen. Omega values will increase, leading to more lift to support these storms. Along with the continuation of amplified conditions with the 23z sounding, CAPE values increase`. The hodograph sounding is also showing winds veering more with height than the previous sounding. This could increase the chance of the forecast area seeing some tornadic thunderstorms during the evening hours.

A tornado watch is in effect for the forecast area with all severe hazards expected for this evening. The main threats being strong winds in excess of 80 mph and a slight chance of seeing a spin up tornado. The main tornado threat will stay to the east, affecting the St. Louis Metro and along the Mississippi River valley.
-Scheerer

On Saturday, we will experience significant mid-to-upper tropospheric troughing, with lingering moisture from the back side of a mature mid-latitude cyclone bringing cloud cover throughout the day. Despite this cloudiness, southwesterly winds will dominate our area for much of the day, as indicated by the SREF model. This flow will help maintain warmer temperatures than typically expected following a cold front.

However, Saturday night, we can expect winds to shift to a northwesterly direction, resulting in rapid cooling. Overnight lows will approach freezing as an arctic airmass cools and dries out the atmosphere, allowing for efficient radiative cooling.

This trend of cooling will continue into Sunday and Sunday night as the high-pressure system associated with the arctic airmass moves southwest of our area. Towards the end of the period, a southerly flow will return, in conjunction with a ridge moving in to start the week. This change will help prevent Sunday night’s lows from dropping much lower than those on Saturday night.

-Schwent