U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus01 kwns 171251 
Storm Prediction Center ac 171249 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0749 am CDT Mon Jun 17 2019 

Valid 171300z - 181200z 

..there is a slight risk of severe thunderstorms central/southern 
High Plains and Lower Middle-Atlantic states... 

Strong to severe storms capable of wind or hail are expected across 
parts of the mid Atlantic this afternoon, and across the central and 
southern High Plains from late afternoon through evening. 

..Central High plains... 
No appreciable change to previous forecast. 

A weak surface cyclone will remain anchored across southeast Colorado with 
an inverted trough/developing front extending northeast into central 
NE. Scattered thunderstorms will develop by early afternoon across 
the southern rockies and late afternoon or evening eastward along 
the trough/front. Moderate buoyancy and 20-30 kt effective shear 
should Foster predominantly multicell clusters capable of mainly 
severe hail and strong wind gusts. The threat will be spatially 
confined by a dearth of instability over western Kansas. 

..southern High Plains... 
No appreciable change to previous forecast. 

Richer boundary-layer moisture characterized by 60s surface dew 
points will remain confined from the Permian Basin southeastward. 
This will promote large buoyancy (mlcape of 2500-3500 j/kg) here at 
peak heating, with more moderate values farther north. Mid-level 
wind profiles will be modest with 500-mb westerlies generally only 
between 15-25 kt. Scattered storms should develop over the higher 
terrain and spread gradually eastward this evening offering a mix of 
isolated to perhaps scattered severe hail/wind. The threat will be 
spatially confined by a dearth of instability over the eastern 

..lower mid-Atlantic states to the Ohio and lower MS valleys... 
Primary change is to expand marginal risk west across the Ohio Valley 
and southwest to the lower MS valley. 

A broad swath of 25-40 kt 500-mb west/southwest flow will exist 
downstream of a low-amplitude shortwave trough that should dampen as 
it tracks from the Ozarks to the lower Ohio Valley through early 
Tuesday. This should aid in the formation of numerous multicells 
this afternoon into early evening. Weak mid/upper-level rates will 
be a limiting factor, suggesting locally damaging winds and 
marginally severe hail should be the primary hazards. The lower 
mid-Atlantic region still appears to have the best relative 
potential for a few cells to acquire mid-level updraft rotation. 
Thus, will maintain the comparatively greater risk here. 

.Grams/dial.. 06/17/2019 


Mesoscale Discussion

acus11 kwns 170616 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 170616 

Mesoscale discussion 1101 
National Weather Service Storm Prediction Center Norman OK 
0116 am CDT Mon Jun 17 2019 

Areas affected...south central Texas through the middle Texas coast 

Concerning...Severe Thunderstorm Watch 390... 

Valid 170616z - 170715z 

The severe weather threat for Severe Thunderstorm Watch 390 

Summary...the greatest threat for organized damaging wind gusts will 
exist in corridor between New Braunfels and Victoria Texas through 

Discussion...organized line of severe storms with embedded 
meso-vortex was located from east of New Braunfels to near 
Floresville. This activity is expected to continue southeast around 
35 kt next couple hours along a slowly southward-advancing outflow 
boundary supported by moist southeasterly inflow within a moderately 
unstable environment. Radar data recently indicated winds to 65 kt 
within 1000 ft of the surface. These storms will likely remain 
capable of producing strong to severe wind gusts during the next 1-2 
hours, and several cell mergers will occur with other storms 
developing along the boundary farther downstream. 

Elsewhere other less organized storms are developing along and north 
of the outflow boundary across southeast Texas and will pose some 
threat for hail and localized gusty winds. 

.Dial.. 06/17/2019 

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


Latitude...Lon 29679789 29549738 29109668 28709678 28619722 28809796 
28949824 29289800 29679789