LIVE MAP (ABOVE) ... SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1116 AM CDT Fri Jul 21 2023
Valid 211630Z - 221200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
MID-SOUTH/TENNESSEE VALLEY/SOUTHEAST...NORTHEAST STATES...AND
SOUTHERN HIGH PLAINS...
...SUMMARY...
Severe thunderstorms capable of wind damage and some hail are
expected across the Mid-South and Tennessee Valley to the Southeast
States, while additional severe storms will be possible across the
Northeast and High Plains.
...AR into the Southeast States...
A large MCS that tracked across southern OK last night is now over
northern/central AR. This system and its attendant MCV will move
into western TN this afternoon, where sufficient heating and a very
moist air mass will support the potential for re-intensification.
If this scenario occurs, locally damaging wind gusts would be the
main concern.
To the southeast of the MCS, a weak surface boundary extends across
southeast AR into portions of MS/AL/GA. A very unstable air mass
will become established this afternoon along this axis, where
scattered thunderstorm development is expected. MLCAPE values
around 3000 J/kg will combine with winds in the 5-7km layer around
30 knots to pose some risk of damaging wind gusts in the stronger
cells. The risk of wind damage will increase later this afternoon
if sufficient thunderstorm coverage can result in more organized
outflows.
...New England...
An upper trough is moving across the northeast states today, with an
associated cold front currently extending across parts of eastern
NY/PA. Clouds have been clearing ahead of the front across western
New England, where temperatures will rapidly warm into the 80s.
Ample low-level moisture is present from southern VT/NH southward,
where upper 60s/lower 70s dewpoints will yield afternoon MLCAPE
values of 1500-2000 J/kg. Forecast soundings show sufficient deep
layer shear for a few organized/rotating storms capable of
strong/damaging wind gusts and perhaps hail for a few hours this
afternoon.
...Northeast NM...
Weak easterly low-level upslope flow is present today over northeast
NM, helping to transport 60s dewpoints westward toward the higher
terrain. Thunderstorms are expected to form in the mountains near
Raton and drift southeastward through the afternoon. Steep
low-level lapse rates and 30-40 knots of effective shear will
promote the development of a few supercells capable of large hail
and damaging wind gusts.
..Hart/Thornton.. 07/21/2023
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/SsXbxq
