Wednesday, May 1, 2019



Tonight - Rain and strong thunderstorms. Low: 58-62.



Thursday - Morning showers and thunderstorms, afternoon clouds. High: 56-60.

 

Thursday Night - Overcast. Low: 48-52.
 

Friday - Overcast. Showers and thunderstorms in the evening. High: 58-62.



 
Saturday - Clouds begin to clear. High: 60-64.  



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Discussion:

We are in for another round of showers and thunderstorms again later this evening through the overnight hours. There is a slight chance these storms will have some hail and  possibly strong winds associated with it. A cold front will  begin to trek east across Missouri Thursday morning. The strongest storms are expected to occur just ahead of the cold front. Flooding will continue to be a concern as we have chances for rain everyday for the remainder of the forecast period. High temperatures for Thursday will be in the early morning hours. As this cold front advances into the area temperatures will steadily drop throughout the day with high's only in the low to mid 50's. We will experience a brief dry period on Friday but another low pressure system will move in Friday afternoon and bring more rain with it. Clouds will linger through much of the forecast period only beginning to clear Saturday afternoon. As the clouds move out of the area temperatures will begin to rebound, with high's on Saturday expected to reach the mid 60's.
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Forecasters: Bongard and Sumrall
Issued: 2:57 p.m., 1 May 2019

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

The stationary boundary over the Midwest continues to reek havoc on Missouri as more heavy rainfall is possible this evening. The brief respite from precipitation today will diminish as PWAT values climb again from around an inch to 1.3 inches of precipitable water. Forcing provided by the stubborn boundary and CAPE values from 1000 to 1500 J/kg will be the catalyst for precipitation development over central Missouri this evening in the form of scattered showers and thunderstorm activity. While the focus for severe weather will be to the southwest over Oklahoma and North Texas the chances for convection here are still better than normal with favorable indexing and BRN values throughout the night. Overnight lows will dip down into the upper 50's as overnight rain and cloud cover will help to drive temperatures lower. Rainfall totals overnight range from 0.5-1 inch from the GFS to 0.25-0.5 inches from the NAM which promotes rain further to the south than its GFS counterpart. We tend to agree which NAM on the higher totals to the south though rainfall totals here will probably be on the higher end of NAM's range. Flooding will become a bigger concern as the rain falls on already saturated ground.

Tomorrow brings a slightly rain cooled soggy day to Columbia as precipitation persists over the region. Forcing slacks off after sunrise though moisture and vorticity profiles remain favorable for continued rain development over the area. Both NAM and GFS promote more of a saturated rain profile than a convective profile through early afternoon. After 18Z a high pressure circulation that has formed over the central and northern Plains will spin east northeast into Iowa helping to push some of the moisture south away from Columbia giving the area a brief chance to dry out (relatively speaking). Afternoon highs will struggle to climb into the 60's with plenty of rain and clouds present overhead Thursday. With a more steady rain expect an additional 0.1 to 0.25 of rainfall accumulation.

Thursday night into Friday yields a reemergence of moisture into central Missouri as low level winds veer back around to the south and PWAT values steadily climb back above 1 inch. Lows overnight will fall back into the upper 40's before sunrise Friday morning. A steady but slow saturation of the profile exists Friday as the moisture to the south slowly wins the battle over Columbia. Precipitation development begins again Friday afternoon around 21Z and continues into Friday night. The favorable NAM model is promoting an additional inch of rainfall by 06Z Saturday. Temperatures Friday will be a carbon copy of Thursdays behavior with a slow climb into the 60's Friday afternoon and a steady rain soaked fall back into the upper 40's before sunrise Saturday morning.

A late night wind shift in the low levels will end rainfall over Columbia (finally!) early Saturday morning. The atmosphere will dry out and stabilize over the course of the day and temperatures will rebound back into the mid to upper 60's. The sun will make a brief appearance Saturday afternoon as the profile clears out moisture and PWAT's fall back to near 0.5 inches.


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