Friday, May 1, 2020

Friday Night - Partly cloudy. Low: 56-60

Saturday - Mostly sunny. High: 80-84

Saturday Night - Partly cloudy. Low: 60-64

Sunday -  Overcast with rain. High: 70-74

Monday - Overcast with evening thunderstorms. High: 72-76
 Thanks to for the icons!

The beginning of the weekend will start off nice with little cloud cover due to the lack of moisture, clouds 
will begin to develop that night leading into Sunday. This is due to a shift in winds causing moisture to 
increase as well as the passage of a cold front, dropping high temps from the mid 80’s to low 70’s. . 
Things begin to change on Sunday, when late day rain should be expected, bringing  in around 0.25 
inches. Clouds will remain through Sunday night into Monday. Thunderstorms are expected Monday 
evening, and should be monitored closely for severity changes.
Forecasters: Balkissoon, Savoy, Heaven
Issued:  5:00pm: May 1, 2020
Technical Discussion (The nerdy stuff we are discussing in class)

WPC model diagnostics suggests a non UKMET model blend, with above average 
confidence so we decided to go with the 12Z GFS. SREF plumes were also referenced 
for temperature and precipitation averages. 

Starting off at 250 hPa, we see winds from the northwest for a majority of the forecast 
period with small shifts from west back to northwest. We will be under the influence
 of the jet max as well, with the jet core staying North of us until the next forecast period. 
Our flow remains zonal until Monday, when a ridge starts to develop as it moves through 
the state of Missouri.

As we move down to the 500 hPa level, we again noted mostly zonal flow with a short
wave on Saturday that quickly disappears back into the zonal flow. On Monday we become 
under the influence of a ridge, which was seen at the 250 hPa level. A deep low was noted 
off the coast of Northern California which should be watched, as it will most likely be 
influencing our weather later in the week. On Sunday at 12Z we noted high vertical velocity 
values, vorticity and saturation, which will be cause for rain. Another chance for rain will 
happen Monday evening when we have Thunderstorm possibilities, which will be discussed 
further down.  

For the 700 hPa Vertical velocity and RH we also take note of Sunday at 12Z where there 
were both regions of high vertical velocity and high RH values.  It should be noted that this 
existed the region relatively quickly.  Consulting the Skew-T at this time we note that there 
is a saturated layer from the 850- 700 hPa level and lift present.  The SREF model runs 
support this precipitation in the amount of approximately 0.25 inches. 

It should be noted that on Monday, from Skew-T analysis, there is possible thunderstorm
activity from Monday evening into Tuesday (Tuesday 0Z).  It was noted that the atmosphere 
is saturated from the surface to 1km above and there was lift as well.   There were significant 
MU CAPE whose numeric value was given by 1492 J/kg.  We also observed a -5 LI indicative
of large instability.  The hodograph was curved and the winds were veering winds whose value 
were not equal in the 0 -3 km level.  This coupled with significant SRH values of 409 m^2/s^2 
(for 1km layer above the ground) and 511m^2/s^2 (for 3km above the ground), indicates the 
possibility for severe weather. Future forecasters should monitor this low pressure system 
moving into our region.  The SREF places us in the vicinity of 0.5 inches of precipitation. 

From the  850 hPa temperature and wind speed.   To account for our warmer weather we 
are experiencing now, we see winds are blowing warm air from the SW into our region.   
We see a shift in winds from SW to NW as a cold front is coming in on Saturday at 12Z.  
On Sunday at 12Z, we see a deformation zone in which winds are being stretched in different 
directions in Central Missouri.  At this time there is colder air in Northern Missouri and warmer
air in Southern Missouri.  Hence indicating there is a thermal gradient associated with this 
deformation zone.  

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