U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus01 kwns 211621 
Storm Prediction Center ac 211619 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1119 am CDT sun Apr 21 2019 

Valid 211630z - 221200z 

..there is a marginal risk of severe thunderstorms late this 
afternoon into early tonight across parts of the Central Plains... 

Marginally severe hail or wind is possible across parts of the 
Central Plains this afternoon and evening, mainly from northern 
Kansas into Nebraska. 

..Central Plains late this afternoon into tonight... 
A series of low-amplitude midlevel troughs will eject 
east-northeastward from nm/Colorado to the mid MO valley, downstream from 
an amplifying trough over the lower Colorado valley. Modest low-level 
moisture return is underway from the western Gulf of Mexico to the 
southern/Central Plains. The moistening will occur beneath a warm 
elevated mixed layer, and much of the warm sector will remain capped 
through the period. Strong surface heating/deep mixing and 
low-level ascent from near a Lee cyclone along the Colorado/Kansas border 
northeastward along a cold front into NE should support thunderstorm 
development this afternoon/evening. MLCAPE of 500-1000 j/kg with 
steep low-level lapse rates and dcape greater than 1000 j/kg will 
favor high-based, multicell storm clusters capable of producing 
isolated severe outflow winds and marginally severe hail late this 
afternoon into early tonight. 

.Thompson/squitieri.. 04/21/2019 


Mesoscale Discussion

acus11 kwns 200443 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 200442 

Mesoscale discussion 0415 
National Weather Service Storm Prediction Center Norman OK 
1142 PM CDT Fri Apr 19 2019 

Areas affected...eastern North Carolina 

Concerning...severe potential...watch unlikely 

Valid 200442z - 200615z 

Probability of watch issuance...20 percent 

Summary...at least a marginal risk for isolated strong to damaging 
wind gusts and perhaps a brief tornado will exist over a portion of 
eastern NC next couple hours. Unless storms begin to show a more 
substantial tendency for organization, a ww will probably not be 

Discussion...a band of storms has recently increased from the Gulf 
Stream into a portion of southeast NC and appears to be developing 
along a pre-frontal convergence boundary. Adjusted for surface 
temperatures and dewpoints, rap forecast soundings suggest the 
storms are probably slightly elevated above a shallow surface stable 
layer, and objective analysis indicates MLCAPE around 500 j/kg. 
Storms remain embedded within very strong largely unidirectional 
wind profiles with 55 kt 0-6 km shear. Based on current 
north-northeast storm motions, 0-1 km storm relative helicity 
remains around 150-200 m2/s2 despite strong low-level speed shear. 
The marginal thermodynamic environment should remain a primary 
limiting factor. Nevertheless, trends will continue to be monitored 
for potential organization. 

.Dial/Dean.. 04/20/2019 

..please see www.Spc.NOAA.Gov for graphic product... 


Latitude...Lon 34037740 35367746 36227701 35977592 34597625 34037740