Wednesday Night: Thunderstorms. Low 61°F
Thursday: Thunderstorms. High: 77°F
Thursday Night: Partly cloudy conditions. Low: 44°F
Friday: Overcast. High: 55°F
Friday Night: Decreasing clouds. Low: 42°F
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General Discussion:
Grab your umbrellas for the next 24 hours! Expect strong thunderstorms Wednesday night into Thursday morning and throughout the early afternoon; the strongest of which can be expected Thursday. After these strong thunderstorms pass through the area, a temperature drop can be expected with overcast conditions until a clear out on Friday.
-Cargill
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Forecasters: Cargill, Robinson
Date Issued: 3/13/2024 5:00 PM CDT
Technical Discussion:
Key Messages:
- Strong thunderstorms will be moving through the CWA from Wednesday night until Thursday afternoon, the strongest of which will be on Thursday.
- A big temperature drop off is modeled for Thursday evening through Friday night.
- Overcast conditions persist until Friday afternoon after the thunderstorms pass.
The NAM and GFS were used for this forecast. At the 300mb level, strong upper-level divergence is modeled to move through the CWA Wednesday night in tandem with a shortwave. With this, strong convergence can be expected at the surface, enhancing severe weather potential. However, there is not a very strong jet stream accompanying this disturbance. That being said, no jet maxes are modeled to move through central Missouri as well.
Strong vorticity is modeled for Wednesday night into Thursday at the 500mb level. This increases chances of strong, severe thunderstorms for this time frame. Furthermore, strong smoothed differential vorticity advection is modeled to the north of the CWA. These two factors are very conducive for unsettled weather and makes the forecast for strong thunderstorms Wednesday night into Thursday more confident.
700mb sees little moisture around the CWA. However, the moisture that does make its way into mid-Missouri is accompanied by strong omega values as well as some WAA around the same time. At 850mb there are strong moisture values present throughout the forecast period. In addition, there is a strong LLJ spreading across the entire state of Missouri. Some WAA of proportional strength to that observed at 700mb is modeled at the same time. However, there is a batch of strong CAA modeled late Thursday into early Friday. This is in association with the forecasted temperature drops around this time. This means that a cold front is moving through the CWA starting early Friday morning.
At the surface, there is not a lot of accumulated precipitation modeled; however, there are dew point temperatures in the 55°F through 60°F modeled late Wednesday into Thursday. These are favorable temperatures for the development of severe weather. Also at the surface is a northward wind shift that occurs early Friday morning. This is further proof of a cold front is to move through the CWA at this time.
The soundings for Wednesday night into Thursday support the notion of severe thunderstorms. The evolution of the severe weather indices, specifically the Lifted Index, K-Index, and Total Totals, are also in support. LI gets down to -4, K-Index to 30, and Total Totals to 57 overnight on Wednesday. This means that there is significant potential for convective development, severe storms, and heavy rainfall. In addition, there is strong CAPE, vertical wind shear, veering winds, and little to no CIN. All of this is conducive to severe thunderstorms and possibly hail. To conclude, severe thunderstorms and a possibility of hail can be expected Wednesday night into the afternoon time on Thursday. Then, thunderstorms will quell moving into late Thursday as a FROPA prepares to propagate through the CWA early Friday. With it will come temperature drops, a northward wind shift, and overcast conditions.
-Cargill