Wednesday, April 24, 2019



 
Tonight - Overcast. Low: 54-58.


 
Thursday - Cloudy. High: 70-74.



 Thursday Night Cloudy with probable rain showers. Low: 42-46.


  
 Friday - Clouds clearing becoming mostly sunny. High: 64-68.


 

Saturday  - Becoming mostly cloudy. Morning showers possible. High: 68-72.

Thanks to IconArchive.com for the icons!





Discussion:
Another cold front makes its way out of the area today leaving behind overcast skies. A warm front will move into the area tonight providing overnight lows that are just a few degrees cooler than the high temperature we experienced today. Thursday will be a mild day with temperatures still cooler than average and the overcast skies will remain. Another cold front will move into the area Thursday afternoon and there will be another chance of rain with this front. After this front moves out of the area the clouds will move out with it bringing sunshine back into the forecast. This will be shortlived however, as yet another cold front will move in Saturday and clouds will begin to increase ahead of this front Saturday morning. Some rain is likely with this cold front Saturday morning but will end by afternoon. Throughout the forecast period temperatures remain cooler than average with our warmest day being Thursday.
============================================================================
Forecasters:  Bongard and Sumrall

Issued: 3:07 p.m.; 24 April 2019

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

Cloudy skies will persist over Columbia tonight thanks to the broad cloud shield associated with a low pressure system sliding across the southern CONUS. A well amplified upper level trough will tilt neutrally over the Southern Plains as it also slowly propagates eastward. Ample vorticity values over Oklahoma and the ArkLaTex will fail to advect into the Midwest in response to a deformation zone that will set up along a line from Kansas City, MO to roughly Chicago, IL. Both NAM and GFS agree that moisture and vorticity will be barricaded to the south and southeast of Columbia as northwesterly flow just to the north and northwest will keep these key precipitation ingredients at bay. Overnight temperatures will fall slightly back into the mid 50's as a low cloud deck remains overhead through the night.

The region will be a crossroads of sorts for two storm systems merging over the central CONUS Thursday. The aforementioned system to the south will slide east northeast through the day Thursday bringing a slight chance for daytime precipitation to Columbia but far better chances for rain in St. Louis and southeast Missouri. Meanwhile a large upper level trough over central Canada and the Northern Plains will drag a shortwave into northern Missouri Thursday afternoon. These two systems will merge seemingly along the I-70 corridor Thursday afternoon and evening giving slightly better chances for precipitation to Columbia Thursday night. Vorticity and moisture with the northern system are not particularly impressive at this point. Northerly flow in the low levels of the column overhead will inhibit any moisture from the southern system from impacting Columbia and with MUCAPE values at 362 J/kg at best the chance for thunderstorm development is minimal according to GFS model soundings. GFS does add 0.15 inches of rainfall to our total by midnight Thursday night while NAM keeps us dry through the same time. Highs Thursday will struggle to reach 70 F before falling back into the 40's Thursday night as skies clear behind the shortwave marching through central Missouri.

Friday will be a mostly sunny day as a post frontal weather pattern greets the forecast area. Northerly low level winds and high pressure development just to the west over Kansas will keep skies mainly clear and temperatures in the upper 60's to near 70 again. Ridging aloft Friday will be short lived as the next weather maker rides the flow out of the Northern Rockies Friday afternoon into the Central Plains by midnight Friday night. Temperatures will slowly fall back into the low 50's Friday night despite low level wind shift to the southwest ahead of the encroaching frontal system. Vorticity and moisture will advect into central Missouri in the early morning hours Saturday as a warm front crawls north. This will aid in early morning precipitation chances though some model disagreement exists. NAM is more fond of precipitation development through 15Z Saturday than GFS whichs promotes this as a generally dry fropa. Temperatures Saturday will climb into the upper 60's near 70 before the ensuing cold frontal passage Saturday evening.

No comments:

Post a Comment