U.S. Severe Weather Forecast for Today

000 
acus01 kwns 190603 
swody1 
Storm Prediction Center ac 190601 


Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0101 am CDT sun may 19 2013 


Valid 191200z - 201200z 


..there is a MDT risk of severe thunderstorms across parts of Kansas/OK/MO and 
southeast Nebraska... 


..there is a slight risk of severe thunderstorms across the plains to upper 
Midwest/middle MS valley... 


... 
Another relatively active severe weather day is expected across a 
broad portion of the plains/Midwest today and tonight. The lead 
portion of a prominent upper trough will spread northeastward over 
the Central Plains...with an increasingly closed upper low over the 
north-Central Plains/middle MO valley by tonight. A corresponding 
surface frontal zone will slowly shift eastward across Kansas/neb/SD 
during the period....with heat-aided secondary surface low 
development anticipated across southern Kansas/western OK/northwest Texas 
in vicinity of a dryline. 


..plains/Ozarks/MO valley to middle/upper MS valley... 
A plume of steep middle-level lapse rates will remain in place /and-or 
quickly be reestablished from Saturday PM convection/ across most of 
the central/Southern Plains to the middle MS valley. A relatively 
moist airmass with middle/upper 60s and some lower 70s f surface 
dewpoints will be in place today within the warm sector to the east 
of a north-Central Plains cold front and Southern Plains dryline. 


Aided by a sustained low level jet/warm advection...scattered 
convection will likely be ongoing early today especially across the 
middle MO valley and upper Midwest. Convective remnants/outflow 
boundaries will be a potential factor for 
redevelopment/re-intensification into this afternoon for areas such 
as the upper Midwest/upper MS valley within a relatively 
moist/unstable airmass along/southwest of a northward-shifting warm 
front. 


South of the early day/ongoing activity...strong heating/aggressive 
destabilization will take place especially from parts of the 
middle/lower MO valley including southeast Nebraska/southern Iowa 
south-southwestward to the east of the dryline across OK and 
north-central/west-central Texas. Here...MLCAPE values are likely to 
exceed 3000 j/kg. Aided by steady height falls and an increasing 
deep layer wind field /40-45 knots effective shear/...surface based 
thunderstorm/discrete supercell development appears most probable to 
initially occur across areas such as Central/Northeast Kansas and 
southeast Nebraska into far northern OK...perhaps by early or 
mid-afternoon. Farther south...near/south of the surface 
low/front/dryline induced triple point...somewhat more 
isolated/higher-based deep convective development is anticipated by 
late afternoon/early evening across central/southern OK southward 
into north/west-central Texas. 


With aid of a diurnally strong south-southwesterly low level 
jet...forecast shear profiles strongly favor long-lived supercells 
capable of very large hail...in addition to tornadoes /perhaps one 
or two strong/ especially where dewpoints hold in the upper 
60s/lower 70s. By early/mid-evening...the proximity of the slowly 
advancing cold front and backing middle-level flow should lead to 
upscale quasi-linear development and an increasing damaging wind 
threat across parts of the lower MO valley/Ozarks and Midwest. 
Meanwhile...near the dryline...a more discrete Mode of sustained 
supercells /again somewhat higher-based especially with southward 
extent/ capable of large hail will be the primary concern...but a 
limited tornado threat and some damaging wind potential may exist as 
well during the late afternoon and evening hours. 


..southeast states/FL... 
A remnant middle-level shortwave trough will shift southeastward across 
this region. This feature may contribute to some strong/potentially 
severe thunderstorms on an isolated basis especially during the 
afternoon/early evening hours. 


.Guyer/marsh.. 05/19/2013 

000 
acus11 kwns 190732 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 190732 
mnz000-ndz000-sdz000-190900- 


Mesoscale discussion 0693 
National Weather Service Storm Prediction Center Norman OK 
0232 am CDT sun may 19 2013 


Areas affected...southeastern ND and adjacent northwestern Minnesota counties 


Concerning...Severe Thunderstorm Watch 178... 


Valid 190732z - 190900z 


The severe weather threat for Severe Thunderstorm Watch 178 
continues. 


Summary...locally strong wind gusts will be possible through 09z 
across the southern extent of ww 178 as an arcing line of storms in eastern 
South Dakota moves into southeastern ND and the adjacent Minnesota counties between 08-09z. 
The severe weather threat is likely diminished in the northern part of ww 
178. 


Discussion...trends in radar imagery over eastern ND indicated the 
storms that moved through the kjms area around 0430z have since 
weakened as they moved into the northwestern part of ww 178. A more stable 
environment across the northern part of this watch suggests the severe 
weather threat is all but over north of a Barnes/Cass counties ND to 
Norman County Minnesota line. 


Meanwhile...radar mosaic indicated an arcing line of storms 
extending generally northwest-southeast from eastern South Dakota into far southwestern Minnesota...with the 
northestern South Dakota portion of this line moving northeastward around 40 knots. The khon 
observation reported a wind gust to 47 knots when the storms moved 
through at 0559z. Although surface based inhibition has 
strengthened per modification of the 00z abr sounding for current 
conditions...the observed near severe wind gust at khon and a northeastward 
movement of this line at 40 knots suggest locally strong wind gusts 
will be possible into the southern part of ww 178 between 08-09z. 


.Peters/Hart.. 05/19/2013 


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


Attention...WFO...fgf...abr...bis... 


Latitude...Lon 46039629 45909789 46359814 46859845 47579841 47729712 
47539623 47309601 46039629