Monroe Upper Keys Severe Watches & Warnings NOAA Weather Radio

Watches & Warnings

Special Statement
Issued: 5:28 AM EST Dec. 19, 2018 – National Weather Service

... Strong cold front will impact the Keys Thursday through
Friday night...

A strong cold front is expected to blast through the Florida Keys
and adjacent coastal waters late Thursday or Thursday night. This
front is expected to bring multiple weather hazards to the Keys
from Thursday morning through Friday evening, including strong to
severe thunderstorms, strong winds on land with gales likely on
the coastal waters, and possible coastal flooding on the Gulf and
Bayside.

The main weather event is expected to occur from Thursday morning
through Friday night, but there is a possibility that a few
isolated strong or severe thunderstorms may develop tonight well
ahead of the cold front. The primary hazards with any
thunderstorms that develop will be strong and gusty winds along
with deadly lightning strikes and heavy rainfall. An isolated
waterspout would also be possible.

The potential for strong to severe thunderstorms ahead of and
along the cold front will be highest from Thursday into Thursday
night. These thunderstorms may organize into a squall line which
could move through the Keys during the afternoon or evening hours.
The primary hazards with any thunderstorms will be strong, gusty
and shifting winds along with deadly lightning strikes and heavy
rainfall. Some of the thunderstorms on Thursday or Thursday night
could become severe with damaging winds and large hail. Isolated
waterspouts will also be possible, and there is a slight risk of
an isolated tornado as well. The Storm Prediction Center continues
to include all of South Florida and the Keys within a severe
thunderstorm risk area for Thursday into Thursday night.

On land, gusty south to southwest winds will increase to 20 to 25
mph on Thursday. Strong sustained west winds around 30 mph with
gusts near 40 mph are expected on Friday, with winds possibly
reaching these speeds beginning on Thursday night. This would
require a Wind Advisory to be issued.

These persistent and strong westerly winds will cause coastal
flooding impacts from the north side of the Lower Keys through the
Gulf side and Bayside communities of the middle and Upper Keys.
Total water levels may reach 3 to 4.5 feet above mean sea level
for the Bayside communities of the Upper Keys on Friday into
Friday night. The maximum water levels will likely occur along
the shores of Blackwater and Buttonwood sounds, around the time of
high tide late Friday afternoon.

Mariners should continue to prepare for a high impact marine
weather event for Thursday through Friday night, and should take
advantage of the benign weather conditions expected during the
daylight hours today to make their preparations. Strong southerly
breezes will develop on Thursday, becoming westerly and increasing
to near gale behind the front Thursday night through Friday and
into Friday night. Small craft advisories will certainly be
needed during this event beginning on Thursday, and there is an
increasing likelihood that gale warnings for sustained winds or
frequent gale force gusts will be needed for much or all of the
Keys coastal waters from Thursday night into Friday night. A gale
watch is now in effect for all of the Keys coastal waters. Very
large seas are also expected with this event, peaking on Friday
at 10 to 17 feet across The Straits of Florida and deep waters of
the southeastern Gulf of Mexico, 5 to 8 feet in Hawk Channel
inside the reef, and 4 to 8 feet across the Gulf waters inside
five fathoms.

Listen to NOAA all hazards weather radio for the latest weather
information, including possible warnings. In addition, please
remember to turn on your radio's severe weather tone activation
feature. Also visit your Florida Keys National Weather Service on
the web at www.Weather.Gov/keywest.


Jacobson

528 am EST Wed Dec 19 2018

... Strong cold front will impact the Keys Thursday through
Friday night...

A strong cold front is expected to blast through the Florida Keys
and adjacent coastal waters late Thursday or Thursday night. This
front is expected to bring multiple weather hazards to the Keys
from Thursday morning through Friday evening, including strong to
severe thunderstorms, strong winds on land with gales likely on
the coastal waters, and possible coastal flooding on the Gulf and
Bayside.

The main weather event is expected to occur from Thursday morning
through Friday night, but there is a possibility that a few
isolated strong or severe thunderstorms may develop tonight well
ahead of the cold front. The primary hazards with any
thunderstorms that develop will be strong and gusty winds along
with deadly lightning strikes and heavy rainfall. An isolated
waterspout would also be possible.

The potential for strong to severe thunderstorms ahead of and
along the cold front will be highest from Thursday into Thursday
night. These thunderstorms may organize into a squall line which
could move through the Keys during the afternoon or evening hours.
The primary hazards with any thunderstorms will be strong, gusty
and shifting winds along with deadly lightning strikes and heavy
rainfall. Some of the thunderstorms on Thursday or Thursday night
could become severe with damaging winds and large hail. Isolated
waterspouts will also be possible, and there is a slight risk of
an isolated tornado as well. The Storm Prediction Center continues
to include all of South Florida and the Keys within a severe
thunderstorm risk area for Thursday into Thursday night.

On land, gusty south to southwest winds will increase to 20 to 25
mph on Thursday. Strong sustained west winds around 30 mph with
gusts near 40 mph are expected on Friday, with winds possibly
reaching these speeds beginning on Thursday night. This would
require a Wind Advisory to be issued.

These persistent and strong westerly winds will cause coastal
flooding impacts from the north side of the Lower Keys through the
Gulf side and Bayside communities of the middle and Upper Keys.
Total water levels may reach 3 to 4.5 feet above mean sea level
for the Bayside communities of the Upper Keys on Friday into
Friday night. The maximum water levels will likely occur along
the shores of Blackwater and Buttonwood sounds, around the time of
high tide late Friday afternoon.

Mariners should continue to prepare for a high impact marine
weather event for Thursday through Friday night, and should take
advantage of the benign weather conditions expected during the
daylight hours today to make their preparations. Strong southerly
breezes will develop on Thursday, becoming westerly and increasing
to near gale behind the front Thursday night through Friday and
into Friday night. Small craft advisories will certainly be
needed during this event beginning on Thursday, and there is an
increasing likelihood that gale warnings for sustained winds or
frequent gale force gusts will be needed for much or all of the
Keys coastal waters from Thursday night into Friday night. A gale
watch is now in effect for all of the Keys coastal waters. Very
large seas are also expected with this event, peaking on Friday
at 10 to 17 feet across The Straits of Florida and deep waters of
the southeastern Gulf of Mexico, 5 to 8 feet in Hawk Channel
inside the reef, and 4 to 8 feet across the Gulf waters inside
five fathoms.

Listen to NOAA all hazards weather radio for the latest weather
information, including possible warnings. In addition, please
remember to turn on your radio's severe weather tone activation
feature. Also visit your Florida Keys National Weather Service on
the web at www.Weather.Gov/keywest.


Jacobson