Tuesday, November 15, 2022








Tuesday Night:
Clouds clearing out. Low: 20
 
 

 


Wednesday:
Increasing clouds. High: 33
 
 



Wednesday Night:
Mostly clear. Low: 19
 
 

 

Thursday:
Mostly cloudy. High: 39
 
 
 



Thursday Night:
Partly cloudy. Low: 17

 

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Discussion:

Low clouds still lingering from our snowfall early this morning will clear out overnight Tuesday. Wednesday will see well below average temperatures in the 30s thanks to cold winds out of the northwest. On Thursday, a slight wind shift out of the southwest will bump temperatures closer to 40 before overnight temperatures plummet once again into the teens Thursday night.

 -Simmons

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Forecasters: Simmons, Meier, Macko

Date Issued: 11/15/2022 5:00 PM CST

Technical Discussion:

 

Both the GFS and NAM were used for cloud forecasting as they both resolved low-level saturation on Tuesday. However, since the NAM12 struggled to verify current temperatures, it was not used to forecast temperatures for the period. Hence a mix of the NBM and the GFS were used to aid temperature forecasting over the next few days. 

At 300mb, the subtropical jet is currently situated off to our south with a jetstreak over the Southern Plains. The subtropical jet and polar jet will condense together over the Appalachia region tonight and into tomorrow. As the jetstream slides east, it will make way for the upper-level trough sinking down from Canada. This will result in northwesterly flow aloft until Thursday 09Z. Toward the end of the forecast period, the polar jet will center itself right over Missouri around 03Z Friday, bringing a surge of arctic air.
 
At 500mb, areas of positive curvature vorticity associated with the mid-level trough hover over Mid-Missouri up until Thursday 00Z. This will help drive waves of cloud cover over the next 36 hours or so. The positively tilted trough will push through the area around Wednesday 21Z as it lifts to the northeast. Moderate vorticity will enter the region Thursday afternoon, but it's not expected to be associated with precipitation due to a lack of rising motion associated with it. 
 
At the lower levels, 700mb moisture appears to exit Missouri starting tonight. This layer will remain relatively dry for our forecast period up until between Thursday 15z to Friday 00z where we'll see some saturation at that level. At 850mb, low pressure is currently situated over the Great Lakes region. As the low moves northeast, it will result in northwest winds over Missouri on Wednesday keeping temperatures on the cooler side. Currently, the LLJ is over the Eastern CONUS helping to advect moisture out of the Gulf of Mexico. As this carries to the east, high pressure over Texas will build in causing a subtle wind shift Thursday out of the southwest.

At the surface, tonight appears to be very cold compared to average. Over Mid-Missouri, the 1000-500mb layer has a depth of 5220m, suggesting a cold evening in accordance with the clearing clouds. Thursday, we do see a slight wind shift out of the southwest which will raise temperatures into the upper 30s. The temperatures will plummet once again Thursday night due to the polar jet entering and a 5180m deep 1000-500mb layer over the region. 
 

-Simmons

 

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