Wednesday, March 10, 2021

Current Conditions at Sanborn Field

Wind Advisory in effect until 6 PM CST Wednesday

 
 

Wednesday Night -
Increasing clouds with rain and thunderstorms. Low: 52-56

 

Thursday -
Mostly cloudy. Rain mainly in the morning. High: 54-58

 

Thursday Night -
Mostly Cloudy. Low:40-44

 

Friday -
  Mostly cloudy. Rain beginning in the afternoon High: 50-54
 
Saturday - Rain. High: 50-54

==================================================== 
 Thanks to IconArchive.com for the icons!

Discussion:

 

As a Low pressure system is positioned to Missouri's Northwest, changes in the local weather should be expected compared to the pleasant Spring-like days we saw at the start of the week. Overnight Wednesday, a surface front will bring rain and thunderstorms. Some of the thunderstorms could be strong, with gusty winds and possibly some very small hail. Most of the strong storms should stay to the West of Columbia. Rainfall amounts will range from 0.25-0.75 inches overnight through Thursday. Another disturbance affects Missouri beginning Friday afternoon and lasting through most of Saturday, bringing plenty of rain. Rain amounts should range from 1-2 inches Friday afternoon through Saturday evening.


====================================================

 
Forecaster: Gasch, McGuire, Vanderpool
Issued: 5:00 PM CST 10 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):

 

The GFS and the NAM both resolved temperature about as well as each other, but the GFS had a better time of resolving the location of the front and the cyclone that are affecting the CONUS.  The biggest feature of this forecast was the rain that will affect the area on Friday night into Saturday.


From the evening hours until Thursday morning, the levels of divergence at the 250 mb level remain fairly low as the flow is directed out of the Southwest.  Into Thursday, the winds in the upper levels remain out of the southwest.  While we are under the influence of a ridge on Wednesday and during the day on Thursday, that ridge begins to grow as heights grow overnight Thursday and throughout the day on Friday.  Late in the day, however, we will begin to see divergence in the upper levels increase.  This increased divergence will affect our weather form about 9 pm through sunrise on Saturday


While there are currently high vorticity values sitting above the Great Plains to our west, the southwest to northeast flow generated at the 250 level helps to keep us clean of the bulk of inclement weather.  Our levels of vorticity at the 500 mb level remain close to zero until Friday morning in advance of our next shot of precipitation.  Beginning Friday morning, we will see a broken line of circulations corresponding to chances of rain at the surface.  This line of circulations will roughly correspond to the I-70 corridor and continue to impact us through about noon on Saturday.


Overnight tonight, we will see elevated levels of both moisture as well as omega values.  Together, the moisture and vertical moisture will lead to cloud growth and the chance for rain overnight.  Thursday, our skies will remain cloudy as the moisture and the vertical motions stay in the area.  Conditions at this level will dry out a bit overnight on Thursday in advance of the rain on Friday.  On Friday, the moisture returns to the Columbia area along with areas of heightened omega values.  These pockets of higher omega will correspond roughly with the broken lines of circulation at the 500 mb level.  These values will remain constant overnight until the omega values subside in the late morning on Saturday.


The conditions in the 850 mb level are very similar to those of the 700 mb level.  Overnight Wednesday, the winds will be out of the south.  However, they will begin to veer signifying warm air advection in advance of any precipitation that we might see overnight.  As our winds will then be out of the Southwest at the 850 mb level, conditions will tend to dry out by Thursday night, as we will be receiving winds from the desert Southwest rather than the wetter Gulf.  As Thursday turns to Friday, our winds will shift from SW to southerly, which will supply the area with more moisture in advance of the rain throughout the day.  


At the surface, we could see a chance of rain overnight Wednesday night.  The largest chance of rain will be far to our north, but central Missouri will see minimal amounts of around 0.25 inches.  Thursday will remain dry throughout the day, but the skies will be cloudy.  The main rainmaker will be Friday and into Saturday.  The Columbia area could see rain amounts between 1 - 2 inches.

No comments:

Post a Comment