SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1150 PM CST Mon Nov 18 2024
Valid 201200Z - 211200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe weather is not expected on Wednesday. Isolated thunderstorms
are most likely over parts of Florida and the Carolinas, and along
the coastal Pacific Northwest.
...Synopsis...
On Wednesday, a deep upper trough will extend from a low over
northern MN southward toward the Ozarks, and will pivot northeast
across the OH Valley and Midwestern states, becoming negatively
tilted. A tight midlevel temperature gradient and 130 kt speed max
will relax somewhat through 00Z. Then, a secondary strong speed max
will develop overnight from the mid MS Valley into the southern
Appalachians.
Meanwhile, an upper ridge will gradually move east toward the
Rockies, with resulting northwest flow regime across the Plains.
At the surface, high pressure will be entrenched from the Rockies
into the central and southern Plains, and extending into the Gulf of
Mexico where strong offshore flow will exist. A low will develop
near Lake Erie during the day, with the cold front pushing into the
Mid Atlantic to the Carolinas late in the day.
...Carolinas...
Low-level moisture with 60s F dewpoints will spread north across the
eastern Carolinas and into southeast VA through 00Z ahead of the
cold front. Deep-layer shear will increase as the upper trough
swings east, with very weak instability developing.
Forecast soundings indicate poor low-level lapse rates/heating, with
substantial midlevel drying. In addition, a prominent subsidence
inversion is present in several model depictions. Given a lack of
appreciable low-level flow fields to support wind gusts, strong
storms are not expected.
...Florida...
Area of thunderstorms are forecast over the eastern Gulf of Mexico
early on Wednesday, with a plume of instability ahead of a cold
front. While some of this activity will move across the Peninsula,
it appears the boundary layer will be relatively cool. As such,
despite the moderate low-level SRH during the morning along the
western coasts, most of it should be rendered in-effective.
...Ohio and Vicinity...
A very strong vorticity maximum will travel east across IN, OH, the
upper OH Valley and into western PA and Lake Erie on Wednesday.
Large-scale ascent will be strong, with rapidly cooling temperatures
aloft. Shallow convection may develop with limited heating along the
cold front, which will itself result in gusty winds with 30 kt
ambient flow just off the surface. While severe storms are unlikely,
a flash or two cannot be ruled out given such cool temperatures
aloft.
...Coastal Pacific Northwest...
Strong cooling aloft on the north size of a midlevel temperature
gradient will exist over northwest OR into western WA with a slowly
weakening midlevel jet. Weak low-level CAPE will develop mainly over
the water. However, some cams show low-topped storms possibly moving
ashore, and wind shear will be strong. While locally strong gusts
cannot be ruled out, the severe risk appears low at this time.
..Jewell.. 11/19/2024
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