U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus02 kwns 241731 
Storm Prediction Center ac 241730 

Day 2 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1230 PM CDT sun may 24 2015 

Valid 251200z - 261200z 

..there is a slight risk of severe thunderstorms across the body of Texas into western 

..there is a marginal risk of severe thunderstorms from Texas into the upper MS 

Scattered to numerous thunderstorms will develop from Texas into the 
middle south region on Memorial Day. Scattered thunderstorms will also 
occur across much of the interior west into the upper Great Lakes 
and Ohio Valley. The greatest risk for severe storms will be across 
Texas with an isolated threat extending north into the southern 

A leading shortwave trough will move rapidly northeastward into the upper MS 
valley and Great Lakes during the day with slight height rises 
behind over the central/northern plains. To the S...another shortwave 
trough will move across Texas during the day...embedded within a 
larger-scale weaker trough covering much of the western and central 
states...providing cool temperatures aloft and increased winds. At 
the surface...a very moist air mass will remain over most of the 
plains states into the MS River Valley with ample instability for 
widespread thunderstorms. 

The primary areas of concern will be over Texas into the arklatex 
region in association with the shortwave trough where strong 
instability and stronger flow exist and will favor multiple clusters 
of organized severe weather. 

Elsewhere...more isolated strong/severe storms are likely from Kansas 
into WI...near a weak low-pressure trough but also behind the 
exiting leading impulse. 

... OK...arklatex... 
widespread strong to severe storms capable of flooding 
rains...isolated/brief tornadoes...damaging winds and some hail are 
expected to form relatively early across central Texas with little 
convective inhibition present and a very moist air mass. Forcing 
with the shortwave trough and favorable low-level storm relative 
flow will strongly favor rapid upscale-growth of one or more large 
storm clusters moving across much of Texas and southern OK...then into the 
arklatex/Sabine River valley by 00z. However...a few supercells are 
also possible...but this will depend on how quickly storms merge 
into clusters. If cells remain more cellular...a few tornadoes could 

..KS into southern WI... 
Daytime heating and convergence within the weak surface trough will 
lead to scattered storm development during the afternoon. A few 
storms are likely to become severe with hail and perhaps localized 
wind damage depending on storm Mode. 

.Jewell.. 05/24/2015