SPC 2000Z Day 1 Outlook

Day 1 Outlook Image

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0154 PM CST Sun Dec 06 2020

Valid 062000Z - 071200Z


Locally damaging winds and a brief tornado are possible across south
Florida and the Keys late tonight through early Monday morning.

...20Z Update...
Will maintain severe probabilities for what is anticipated to be an
increasing potential late tonight (mainly after 06Z) for a couple of
thunderstorms capable of localized wind damage and/or a tornado.
This will be as a cluster of storms likely moves in from the Gulf of
Mexico and/or as other semi-discrete storms develop ahead of any
such cluster.

..Guyer.. 12/06/2020

.PREV DISCUSSION... /ISSUED 1019 AM CST Sun Dec 06 2020/

...South Florida...

Southern-stream shortwave trough situated over TX late this morning
will phase with a northern-stream trough and accelerate through the
Southeast States tonight. Stalled front located just south of the FL
Keys will return to deep South FL tonight. This will result in a
small, moist warm sector spreading inland, while a southwesterly
low-level jet strengthens across this region late tonight in
response to the approaching shortwave trough. 

The atmosphere across south FL will undergo modest destabilization
as upper 60s to near 70F dewpoints advect inland. However, very weak
lapse rates (generally less than 5.5 C/km) will contribute to a
marginal thermodynamic environment with MLCAPE below 800 J/kg.
Numerous showers and thunderstorms will develop within the region of
isentropic ascent north of the front, and widely scattered to
scattered surface-based storms are also possible along and south of
this boundary later tonight. Vertical wind profiles will strengthen
with 40+ kt effective bulk shear, along with increasing 0-1 km
hodograph size as the low-level jet evolves late tonight. A couple
of bowing structures and embedded supercells are possible with an
attendant threat for a few damaging gusts and a brief tornado. Due
to the expected limiting factors imposed by an anticipated marginal
thermodynamic environment, will maintain MRGL risk category this
update but continue to monitor for a possible SLGT upgrade in later

Read more
There’s more click here.

Comments are closed.