ACUS01 KWNS 090103

SWODY1

SPC AC 090101



Day 1 Convective Outlook  

NWS Storm Prediction Center Norman OK

0801 PM CDT Thu May 08 2025



Valid 090100Z - 091200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF

SOUTH TEXAS...THE TENNESSEE VALLEY...SOUTHERN APPALACHIANS AND

SOUTHEAST...



...SUMMARY...

Scattered thunderstorms with severe wind gusts and large hail will

continue this evening over parts of the Tennessee Valley, southern

Appalachians and Southeast. Severe wind gusts and large hail are

also expected across parts of south Texas, where hailstones of

greater than 2 inches in diameter will be possible.



...Tennessee Valley/Southern Appalachians/Southeast...

Latest water vapor imagery shows a positively-tilted mid-level

trough over the Ohio Valley, with an east-to-west oriented plume of

mid-level moisture from the mid Mississippi Valley into the south

and central Appalachians. At the surface, a quasi-stationary front

is analyzed in the Ohio Valley. To the south of the front over the

Ohio and Tennessee Valleys, surface dewpoints are in the mid 50s to

the mid 60s F. The RAP has moderate instability in place from the

Tennessee Valley eastward into the southern Appalachians and

southward into the Gulf Coast states. Scattered thunderstorms are

ongoing, concentrated along the northern edge of moderate

instability from Kentucky and Tennessee eastward into western North

Carolina. RAP forecast soundings in this vicinity early this evening

have 0-6 km shear ranging from 35 to 45 knots, mostly due to speed

shear in the mid-levels. This, combined with 0-3 km lapse rates in

the 7.5 to 8 C/km range, should be favorable for severe gusts with

the stronger cells. The shear will also support supercell

development with large hail possible. The severe threat should

become more isolated later this evening as instability decreases

across the region.



...South Texas...

A shortwave trough, with multiple vorticity maximums, appears to be

located in the lower Rio Grande Valley, according to water vapor

imagery. Scattered strong to severe thunderstorms are ongoing ahead

of the trough from near Laredo extending eastward onto the Texas

Coastal Plain. From the storms southward, moderate instability is

analyzed by the RAP, with MLCAPE estimated to be in the 1000 to 2000

J/kg range. The airmass is very moist with surface dewpoints in the

lower to mid 70s F. Within this moist airmass, RAP forecast

soundings early this evening have 0-6 km shear near 50 knots, with

700-500 mb lapse rates near 7.5 C/km. This environment will support

supercells with large hail, and hailstones greater than 2 inches in

diameter will be possible within the more intense cores. Isolated

severe gusts may also occur within the stronger downdrafts. The

ongoing severe storms will track southeastward across the remainder

of south Texas this evening...see MCD 749.



..Broyles.. 05/09/2025



$$