Special Marine Warning 231, NWS Key West, FL

084 
FZUS72 KKEY 262312
MWSKEY

Marine Weather Statement
National Weather Service Key West FL
712 PM EDT Sun Sep 26 2021

GMZ054-055-074-075-262330-
/O.CON.KKEY.MA.W.0231.000000T0000Z-210926T2330Z/
712 PM EDT Sun Sep 26 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 730 PM EDT...

For the following areas...
Straits of Florida from west end of Seven Mile Bridge to 20 nm west
of Dry Tortugas out 60 nm...

At 711 PM EDT, strong thunderstorms were located along a line
extending from 11 nm southeast of Twenty-Eight Foot Shoal Light to 15
nm south of Cosgrove Shoal Light, moving southwest at 20 knots.

HAZARD...Wind gusts 34 knots or greater.

SOURCE...National Weather Service Meteorologist.

IMPACT...Expect wind gusts in excess of 34 knots, suddenly higher 
         waves, frequent lightning, and heavy downpours.

Strong thunderstorms will remain over mainly open waters.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare for wind gusts in excess of 35 knots, steep and fast-building
seas, frequent lightning strikes, and blinding downpours. Stay low or
go below, and make sure all on board are wearing life jackets.

&&

LAT...LON 2405 8227 2425 8261 2434 8229 2426 8212
TIME...MOT...LOC 2311Z 030DEG 18KT 2425 8234 2421 8222 

HAIL...0.00IN
WIND...>34KTS

$$

KR

489 
FZUS72 KKEY 262321
MWSKEY

Marine Weather Statement
National Weather Service Key West FL
721 PM EDT Sun Sep 26 2021

GMZ054-055-074-075-262331-
/O.EXP.KKEY.MA.W.0231.000000T0000Z-210926T2330Z/
721 PM EDT Sun Sep 26 2021

...THE SPECIAL MARINE WARNING WILL EXPIRE AT 730 PM EDT...

The affected areas were... 
Straits of Florida from west end of Seven Mile Bridge to 20 nm west
of Dry Tortugas out 60 nm...

The thunderstorms have weakened and no longer pose a significant
threat to boaters.

LAT...LON 2405 8227 2425 8261 2434 8229 2426 8212
TIME...MOT...LOC 2321Z 061DEG 15KT 2424 8237 2420 8225 

$$

KR

Area Forecast Discussion
National Weather Service Key West FL
308 PM EDT Sun Sep 26 2021

.DISCUSSION...
A broad long wave trough stretches southeast across the eastern
United States and northern Florida. Water vapor loops portray
steady deamplification of this feature. Surface observations place
the center of a high pressure system over the extreme
southeastern United States and northern Florida. As such,
northeasterly breezes have returned to the Florida Keys. Isolated
showers and thunderstorms are moving through Florida Bay and the
Upper Keys, and a thundery cumulus streamer is reaching downwind
from the Lower Keys. Otherwise, shower activity has been limited
across the island chain for much of the day. Temperatures are in
the upper 80s to near 90 with dewpoints in the mid 70s. Modified-
Continental air has reached Southwest Florida and areas near Lake
Okeechobee.

.FORECAST...
Forecast reasoning has not changed appreciably with this cycle.
The long wave trough will lumber to the east of its current
position, then roughly stall out over the extreme western North
Atlantic. Upstream over the Plains and Mississippi River Valley,
and equally impressive upper level ridge will stall, sending
reinforcing shots of short waves down the Appalachians into the
long wave trough. At the surface, a continental anticyclone will
remain over the southeastern United States, maintaining the
northeast breezes and periodic shots of less-tropical air. A few
days ago, episodes of mid to upper 60s dewpoints were a little
more bullish. Nevertheless, dewpoints near 70 will be possible
Monday through at least Wednesday. Additionally, very dry air from
850 to 500 mb will limit thunder for several days.

The tropical airmass will be lurking to the south, and there
remains some uncertainty with the timing of its return. Any shifts
in the steering flow from northeast, to northeast to east would
send an undulation in the easterlies back across the Keys. For
now, we highlight a return to near normal rain chances on
Thursday, but the actual return could be sooner or later. By next
weekend, the gradient across the Keys will tighten, resulting in
fresh northeast to east breezes and sloppier marine conditions
across the Keys.

&&

.MARINE...
There are no watches, warnings, or advisories currently in effect
for the coastal waters of the Florida Keys. An extended period of
moderate northeast to east breezes are expected tonight through
Thursday. Breezes will tend to peak overnight and subside somewhat
during the day. By Thursday night or Friday, breezes will freshen
further.

&&

.AVIATION...
VFR conditions will prevail at both EYW and MTH island terminals
through tomorrow afternoon. Winds have slowly increased through
the day, now northeast near 10 knots. The wind increase has
allowed convection near the Andros Island and Mainland Monroe to
move into the vicinity of the island chain and terminals,
resulting in an addition of VCSH for both terminals through early
evening. Another round of convection may occur overnight, however
uncertainty in timing and location has resulted in no extension of
VCSH at this time.

&&

.CLIMATE...
On this day in 2011, the daily record rainfall of 3.36 inches was
recorded in Key West. Rainfall records in Key West date back to
1871.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  79  88  78  88 / 30 20 10 20
Marathon  78  89  78  89 / 30 20 10 20

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...None.
&&

Public/Marine/Fire...CLR
Aviation/Nowcasts....Williams
Data Acquisition.....MRR

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Hazardous Weather Outlook
National Weather Service Key West FL
433 AM EDT Sun Sep 26 2021

FLZ076>078-GMZ031>035-042>044-052>055-072>075-270845-
Monroe Upper Keys-Monroe Middle Keys-Monroe Lower Keys-
Florida Bay including Barnes Sound, Blackwater Sound, and
Buttonwood Sound-
Bayside and Gulf side from Craig Key to west end of Seven Mile
Bridge-
Gulf waters from East Cape Sable to Chokoloskee 20 to 60 NM out
and beyond 5 fathoms-
Gulf of Mexico including Dry Tortugas and Rebecca Shoal Channel-
Gulf of Mexico from west end of Seven Mile Bridge to Halfmoon
Shoal out to 5 Fathoms-
Hawk Channel from Ocean Reef to Craig Key out to the reef-
Hawk Channel from Craig Key to west end of Seven Mile Bridge out
to the reef-
Hawk Channel from west end of Seven Mile Bridge to Halfmoon Shoal
out to the reef-
Straits of Florida from Ocean Reef to Craig Key out 20 NM-
Straits of Florida from Craig Key to west end of Seven Mile
Bridge out 20 NM-
Straits of Florida from west end of Seven Mile Bridge to south of
Halfmoon Shoal out 20 NM-
Straits of Florida from Halfmoon Shoal to 20 NM west of Dry
Tortugas out 20 NM-
Straits of Florida from Ocean Reef to Craig Key 20 to 60 NM out-
Straits of Florida from Craig Key to west end of Seven Mile
Bridge 20 to 60 NM out-
Straits of Florida from west end of Seven Mile Bridge to south of
Halfmoon Shoal 20 to 60 NM out-
Straits of Florida from Halfmoon Shoal to 20 NM west of Dry
Tortugas 20 to 60 NM out-
433 AM EDT Sun Sep 26 2021

This Hazardous Weather Outlook is for the Florida Keys and
adjacent coastal waters.

.DAY ONE...TODAY AND TONIGHT

Isolated thunderstorms are expected today and tonight. The primary
thunderstorm hazard will be dangerous lightning strikes.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

Isolated thunderstorms are expected. The primary thunderstorm
hazard will be dangerous lightning strikes.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

NB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KEY WEST FL
252 PM EDT SUN SEP 26 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0235 PM     MARINE TSTM WIND 11 ESE CARD SOUND BRIDG 25.23N 80.21W
09/26/2021  M39 MPH          GMZ052             FL   MESONET

            A WIND GUST OF 34 KTS WAS RECORDED BY THE WEATHERFLOW
            MESONET SITE AT CARYSFORT REEF LIGHT AT 235 PM EDT.

&&

DE SOLO