Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0245 PM CDT Sun Apr 21 2024
Valid 212000Z - 221200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHEAST
GEORGIA INTO NORTHERN FLORIDA...
...SUMMARY...
Isolated damaging gusts and marginally severe hail remain possible
for a few hours this afternoon/evening across southeast Georgia and
north Florida.
...Southeast Georgia and northern Florida...
Within the past few hours, a transient supercell on the northern
fringe of the effective warm sector along the SC coast produced a
measured severe (58 mph) wind gust, indicating that the environment
across northern FL into southeast GA remains conducive for severe
storms. However, convection has struggled to maintain intensity over
the past few hours despite steadily diminishing MLCIN - possibly
owing to a temporal displacement between the initial storms and the
more favorable thermodynamic environment that is currently becoming
established. Renewed attempts at convective initiation along the
cold front are noted across south-central GA, so a severe wind/hail
risk should persist for the next several hours (see forthcoming MCD
#504 for details). Latest CAM guidance suggests this potential will
be maximized between 21-00 UTC across southeast GA into far northern
FL before the front moves off the GA coast and nocturnal cooling
begins to hinder surface-based convection further south into the FL
peninsula.
..Moore.. 04/21/2024
.PREV DISCUSSION... /ISSUED 1124 AM CDT Sun Apr 21 2024/
...North FL/south GA this afternoon/evening...
Visible satellite imagery late this morning shows a cumulus field
and a destabilizing airmass to the east of an ongoing band of
convection near a southwest-northeast oriented front. Ample heating
over the area to the east of patchy cirrus will promote temperatures
warming into the lower 80s deg F. 12z model guidance so far has a
negative bias on surface dewpoints across north FL compared to
observations (3-6 deg F too dry). This is partially explained by a
richer moist profile observed through almost 850 mb via the 12z
Tallahassee raob. As a result, slightly higher dewpoints (upper 60s
deg F) and greater buoyancy (1000-1500 J/kg MLCAPE) are expected
than previously forecast. Water-vapor imagery shows a lead
disturbance moving east across the central Gulf Coast, and it will
reach the northeast Gulf by late this afternoon/early evening.
Ascent and some strengthening in flow will aid in some storm
organization (reference 50-kt 2-6 km flow at Tallahassee on the 88D
VAD). Limited low-level convergence and a warm layer near 800 mb
may act to hinder an otherwise more organized potential severe
setup. Regardless, isolated 50-65 mph gusts and marginally severe
hail are possible with the stronger storms this afternoon into the
early evening.
Read more CHECK UPDATE ZOOM GRAPHIC
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