Mesoscale Discussion 2133
NWS Storm Prediction Center Norman OK
0723 PM CDT Tue Oct 08 2024
Areas affected...southwestern coastal Florida and the lower Keys
Concerning...Severe potential...Watch unlikely
Valid 090023Z - 090530Z
Probability of Watch Issuance...20 percent
SUMMARY...Supercell development posing risk for
waterspouts/tornadoes is possible offshore of southwestern Florida
coastal areas and north of the lower Keys much of tonight. It
appears that this may not spread into coastal areas and inland until
closer to or beyond daybreak. However, trends are being closely
monitored.
DISCUSSION...A weak/diffuse surface frontal zone in advance of
Hurricane Milton has been a focus for persistent discrete rotating
storms the past several hours, roughly 50-150+ miles north-northwest
through west of the Key West vicinity. This activity has likely
been supported by forcing for ascent associated with weak low-level
warm advection and moderate to strong southwesterly deep-layer
shear. Low-level hodographs are likely rather modest to weak, but
clockwise curved, and in the presence of seasonably high
boundary-layer moisture content this probably has been sufficient to
support low-level mesocyclones occasionally producing waterspouts.
Through late evening and into the overnight hours, as Milton slowly
accelerates northeastward across the southeastern Gulf of Mexico,
the developing warm frontal zone probably will begin to surge
northward to its immediate north and northeast. However, closer to
southwestern Florida Peninsula coastal areas, the Rapid Refresh
suggests that the boundary may remain quasi-stationary into early
portions of the overnight hours, and may not begin approaching the
Naples/Fort Myers vicinities until 09-12Z. Even at that time,
low-level hodographs may only just be in the process of modest
enlargement, as flow around 850 mb becomes southeasterly and begins
to increase in excess of 30 kt. And, based on forecast soundings,
appreciable boundary-layer destabilization may not develop inland of
coastal areas until after daybreak.
..Kerr/Edwards.. 10/09/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...KEY...
LAT...LON 25238364 25588350 26158314 26078224 25848148 25408105
24968121 24668212 24248280 24538355 25238364
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