U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus01 kwns 230052 
Storm Prediction Center ac 230051 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0751 PM CDT Mon Apr 22 2019 

Valid 230100z - 231200z 

..there is a slight risk of severe thunderstorms for portions of 
southeast New Mexico and northwest Texas... 

Severe thunderstorms capable of mainly hail and damaging winds are 
possible over portions of southeast New Mexico and northwest Texas 
this evening into the overnight. 

..southern High Plains tonight... 
A mid-level low along the Arizona/Mexico border will slowly drift east 
tonight and favor shower/thunderstorm development through early 
Tuesday morning. A surface front was analyzed this evening from 
central OK southwest into West Texas with increasingly moist low-level 
flow impinging on the Permian Basin. Warm advection/frontal lift 
will promote thunderstorms primarily along and north of the boundary 
this evening. Although moisture is not considered overly robust, 
steep mid-level lapse rates (7.5-8 degrees c/km) and strong 
high-level flow will aid in storm organization and the potential for 
large hail/severe gusts with the stronger storms. An arcing band of 
strong/severe storms is expected over eastern nm this evening and 
additional storms are likely to develop farther east from parts of 
northwest Texas into southwest OK late. For short-term details, please 
refer to mesoscale discussion number 421. 

..northwest Illinois this evening... 
A smaller-scale mid-level speed Max (50 kt at 500mb per the dvn 
raob) will move across the mid MS valley this evening. A squall 
line exhibiting organization yielded a 40-kt gust at kdvn. Despite 
gradual cooling during the next 1-2 hours, relatively steep lapse 
rates co-located with adequately strong/veering flow in the lowest 
6km may allow a marginal wind-damage risk to linger through the 
early evening across portions of northwest Illinois before boundary-layer 
stabilization lessens the strong-storm risk. 

.Smith.. 04/23/2019 


Mesoscale Discussion

acus11 kwns 230224 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 230224 

Mesoscale discussion 0422 
National Weather Service Storm Prediction Center Norman OK 
0924 PM CDT Mon Apr 22 2019 

Areas affected...Texas South Plains...northwest Texas into 
southwestern Oklahoma 

Concerning...Severe Thunderstorm Watch 94... 

Valid 230224z - 230400z 

The severe weather threat for Severe Thunderstorm Watch 94 

Summary...storms may continue to pose some risk for mostly 
marginally severe hail through late evening, while developing 
northeastward across the Texas South Plains, into southwestern 
Oklahoma. Severe wind potential appears low, but potential still 
exists for some increase in strong surface gusts by midnight-1 am 

Discussion...discrete thunderstorms have increased in number during 
the past few hours. Mrms-mesh suggests that strong cells may still 
be occasionally producing marginally severe hail, and this probably 
will continue at least another few hours in the presence of strong 
deep-layer shear and thermodynamic profiles characterized by steep 
mid-level lapse rates and weak to moderate cape. 

Activity remains generally focused along a thermal gradient in the 
850-700 mb layer, where it remains possible that forcing for ascent 
associated with warm advection, beneath broadly difluent and 
divergent upper flow, could support further upscale convective 
growth and consolidation through 04-06z. If this occurs, a 
gradually conglomerating surface cold pool could be accompanied by 
some potential for strong, gusty surface winds. Otherwise, as 
southerly low-level flow remains generally weak, damaging wind 
potential appears generally low. 

.Kerr.. 04/23/2019 

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


Latitude...Lon 33620226 34849958 33999937 33499962 32810130 32640228