SPC Mar 5, 2025 1300 UTC Day 1 Convective Outlook

SPC 1300Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0658 AM CST Wed Mar 05 2025

Valid 051300Z - 061200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN
SOUTH CAROLINA INTO CENTRAL AND EASTERN NORTH CAROLINA AND INTO
SOUTHERN AND SOUTHEAST VIRGINIA...

...SUMMARY...
Severe thunderstorms capable of producing scattered damaging-wind
gusts and a few tornadoes are possible today across parts of the
eastern Carolinas into southeast Virginia.  Other strong to severe
storms may occur across parts of Florida and east Georgia, and also
from the Allegheny Plateau into the Mid Atlantic.

...VA south to north FL...
Water-vapor imagery this morning shows a mid-level low meandering
east over the mid MS Valley towards the southern Great Lakes.  The
larger-scale trough will shift eastward from the lower OH
Valley/central Gulf Coast through the Carolinas/Mid-Atlantic states
by daybreak Thursday.  

An ongoing convective band in the form of a broken QLCS structure
extends from western NC southward into north FL.  Strong southerly
low-level flow is aiding in the transport of richer moisture (lower
60s dewpoints into SC) northward ahead of the convective band. 
Little to no lightning has been observed with the band this morning,
but as it moves eastward into a slightly more buoyant airmass from
central SC east/northeast into VA, the squall line is forecast to
intensify coincident with modest diurnal heating.  Very strong low
to deep-layer shear will support storm organization mainly in the
form of bowing structures/mesovortices.  An attendant threat for
tornadoes will probably develop with the more persistent/long-lived
embedded circulations in addition to wind damage focused near
inflections and bowing segments of the band.  

While weak instability is forecast farther south over GA/FL,
large-scale ascent will be lifting north of this region.  Strong
deep-layer flow will still be in place, and coupled with
modest instability, this should result in some continued organized
convection capable of strong to severe gusts.

...Upper OH Valley/PA vicinity...
Farther north, instability will be quite limited given a cooler
boundary layer and dewpoints generally in the mid 40s to mid 50s F.
However, cold temperatures aloft will result in steep midlevel lapse
rates and MUCAPE 250-500 J/kg.  Additionally, closer to the surface
low, vertically veering wind profiles with effective shear values
near 40 kt, will support isolated low-topped transient supercells
and perhaps linear segments.  Strong to severe gusts, isolated hail
and perhaps a tornado will be possible with this activity this
afternoon before weakening this evening.

..Smith/Jewell.. 03/05/2025

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