SPC May 30, 2025 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1105 AM CDT Fri May 30 2025

Valid 301630Z - 311200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS
OF CENTRAL AND EASTERN NORTH CAROLINA...MUCH OF SOUTH CAROLINA...AND
EAST-CENTRAL GEORGIA...

...SUMMARY...
Scattered to numerous severe storms are possible this afternoon and
evening, with 55-70 mph gusts capable of wind damage extending from
the Mid-Atlantic states into the Southeast.  The potential for a few
tornadoes exists from the Mid-Atlantic states into the Carolinas.

...Mid-Atlantic/Carolinas and Southeast...
Water-vapor imagery shows a potent mid- to upper-level trough over
the OH-TN Valleys with this feature forecast to move into the
Mid-Atlantic states/Carolinas by late evening.  In response to this
shortwave trough, a deepening surface cyclone will move from the
KY/WV border east-northeastward along a quasi-stationary front into
southeast PA/NJ by evening.  A trailing cold front will move across
parts of the Southeast, Carolinas, and Virginia.  Wind profiles
across the warm sector of the deepening cyclone will be seasonably
strong, but instability is expected to be tempered by weak midlevel
lapse rates and substantial cloud cover.

As large-scale ascent with the approaching shortwave trough develops
across the warm sector, thunderstorms are expected to develop along
and near the cold front.  A mix of cells and linear bands will
gradually evolve into broken band convective structures with time as
storms move east.  Strengthening 700-mb flow (40-50 kt) amidst
diurnally steepened 0-2 km lapse rates will favor strong to severe
gusts.  Damaging winds (55-70 mph) are expected to be the primary
severe hazard, although a tornado threat will exist primarily with
bowing segments.

Farther north, the northern extent of a destabilizing warm sector
immediately ahead of the deepening surface low, will favor an
increasing severe risk this afternoon.  Scattered storm development
is initially forecast near the higher terrain with additional
cellular development expected (consistent signal in recent HRRR
runs) in the northern VA to southeast PA corridor late this
afternoon and especially into the evening.  Given the moist low
levels and favorably shaped hodographs in proximity to the surface
low, have enlarged 5-percent tornado probabilities for a
supercell-tornado risk.  Some consideration for higher tornado
probabilities was given, but confidence was too low at this time. 
Damaging gusts and large hail are also possible with the stronger
storms.  

Along the Gulf Coast from southeast TX into the western FL
Panhandle, moderate/strong buoyancy and 25-30 kts of westerly shear
will be present. Here, scattered clusters of strong/severe storms
posing a risk for mainly damaging winds are expected to develop this
afternoon. 

...Eastern WI into northern IL/IN and Lake Michigan...
A mid/upper-level shortwave trough and strong northerly jet will
move southward across parts of the Great Lakes during the afternoon
and evening.  Modest low-level moisture will limit buoyancy, but
relatively steep midlevel lapse rates and cold temperatures aloft
will support thunderstorm development during the late afternoon and
evening. Localized damaging gusts and hail could accompany the
strongest storms.

...Eastern NM into Far West TX...
Low-level southeasterly flow will maintain modest boundary-layer
moisture across parts of NM and West TX. Moderate instability and
25-kt midlevel northwest flow could support a few strong storms
capable of isolated hail and strong to severe gusts this afternoon
and evening.

..Smith/Halbert.. 05/30/2025

StormPrep