by SPC Forecast Products | Oct 8, 2024 | Weather and Emergency Alerts
No watches are valid as of Wed Oct 9 00:45:02 UTC 2024.
by SPC Forecast Products | Oct 8, 2024 | Weather and Emergency Alerts
MD 2133 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHWESTERN COASTAL FLORIDA AND THE LOWER KEYS
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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by SPC Forecast Products | Oct 8, 2024 | Weather and Emergency Alerts
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0353 PM CDT Tue Oct 08 2024
Valid 101200Z - 161200Z
Confidence in widespread fire-weather concerns over the CONUS
through the extended forecast period is low. Strong ridging in place
over the central and western US will remain through midweek.
Stronger mid-level flow, and a resulting increase in surface winds,
will begin to develop over parts of the northern Rockies and Great
Basin D3/Thursday and D4/Friday, as a strong cold front progresses
eastward. The increase in winds may overlap with areas of dry fuels
and continued warm/dry conditions supporting some elevated
fire-weather concerns. However, the air mass behind the front should
quickly moderate, casting uncertainty on how widespread the
fire-weather threat will be.
Some fire-weather risk may extended into parts of the Plains and
Great Basin late this week and into this weekend. Exact details with
the frontal position/timing remain limited, but some potential for
dry and windy conditions will overlap with very receptive fuels. A
second stronger front will rapidly progress southward over the
Rockies and central US later this weekend and into next week. This
could support another period of dry and windy conditions across the
Plains and Great Basin, but forecast confidence remains limited.
..Lyons.. 10/08/2024
...Please see www.spc.noaa.gov/fire for graphic product...
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by SPC Forecast Products | Oct 8, 2024 | Weather and Emergency Alerts
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Tue Oct 08 2024
Valid 082000Z - 091200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WEST-CENTRAL/SOUTH FLORIDA AND THE KEYS...
...SUMMARY...
An isolated tornado threat associated with Hurricane Milton may
develop late tonight into early Wednesday morning across parts of
west-central/south Florida and the Keys.
...20Z Update...
Outside of minor adjustments to the General Thunderstorm areas over
the Great Basin and Lower Great Lakes (based on the latest satellite
and radar data), no changes were made to the outlook with this
update. Any organized thunderstorms capable of producing strong
gusts and brief waterspouts/tornadoes should generally remain
offshore of Southwest FL and north/west of the Keys until the
overnight/early morning hours -- when the stronger low-level shear
and mesoscale forcing accompanying Hurricane Milton overspread the
area.
..Weinman.. 10/08/2024
.PREV DISCUSSION... /ISSUED 1104 AM CDT Tue Oct 08 2024/
...Florida...
The latest NHC forecast shows Hurricane Milton moving into the
southeastern Gulf of Mexico late tonight into early Wednesday
morning. Milton's wind field is also forecast to expand
through the period, with enlarging hodographs expected initially
near the Keys and spreading north-northeast into the southern and
southwest parts of the Peninsula during the 09/06-12 UTC period.
Given a moist/tropical airmass in place across the FL Straits and
Keys this afternoon, a gradual northward movement of this airmass
coincident with the strengthening wind fields, will support
potential for transient supercell structure with the stronger cells
embedded in convective bands. As a result, a risk for a couple of
brief tornadoes may exist across these areas during the 09/06-12 UTC
time frame.
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