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GMZ043 Expires:202312050345;;906564 Fzus52 Kkey 042135 Cwfkey
coastal waters forecast for the florida keys national weather service key west fl 435 pm est Mon dec 4 2023
florida bay, hawk channel and straits of florida from ocean reef to south of dry tortugas, and the extreme southeastern gulf of mexico, including the florida keys national marine sanctuary
seas are given as significant wave height, which is the average height of the highest 1/3 of the waves. Individual waves may be more than twice the significant wave height.
gmz042>044-050345- 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- 435 pm est Mon dec 4 2023
Tonight..Northwest to north winds 5 to 10 knots, becoming north and increasing to 10 to 15 knots late. Seas around 1 foot. West of cosgrove shoal light, seas around 1 foot, building to 1 to 2 feet. NEarshore waters smooth to a light chop, becoming a light to moderate chop. Isolated showers.
Tuesday..North to northeast winds 10 to 15 knots, decreasing to near 10 knots in the afternoon. Seas 1 to 2 feet, except around 2 feet west of cosgrove shoal light. NEarshore waters a light to moderate chop, becoming a light chop. Isolated showers.
Tuesday night..North winds 10 to 15 knots, increasing to 15 to 20 knots after midnight. Seas 1 to 2 feet, building to 2 to 3 feet. NEarshore waters a light to moderate chop, becoming choppy. Isolated showers.
Wednesday..North winds 15 to 20 knots. Seas 2 to 3 feet, except 3 to 4 feet west of cosgrove shoal light. NEarshore waters choppy. Isolated showers.
Wednesday night..North winds near 20 knots, becoming north to northeast. Seas 2 to 3 feet, except 4 to 5 feet west of cosgrove shoal light. NEarshore waters rough.
Thursday..North to northeast winds 15 to 20 knots, becoming northeast to east and decreasing to near 15 knots. Seas 2 to 3 feet, except 3 to 5 feet west of cosgrove shoal light. NEarshore waters choppy, becoming a moderate chop.
Thursday night..Northeast to east winds 15 to 20 knots, becoming east. Seas 2 to 4 feet. NEarshore waters choppy.
Friday and Friday night..East winds 15 to 20 knots. Seas 3 to 4 feet. NEarshore waters choppy. Isolated showers.
Saturday..East winds 15 to 20 knots, becoming east to southeast. Seas 3 to 4 feet. NEarshore waters choppy. Isolated showers.
Saturday night..East to southeast winds 15 to 20 knots. Seas 3 to 4 feet. NEarshore waters choppy. Isolated showers.

GMZ005 Synopsis For Keys Coastal Waters From Ocean Reef To Dry Tortugas 435 Pm Est Mon Dec 4 2023
Synopsis..Gentle to moderate northerly breezes will persist tonight through Tuesday as a weak cold front flushes through the keys. A second, much stronger cold front will push through the coastal waters late Tuesday or early Wednesday, with fresh northerly breezes expected in its wake. Strong high pressure will slide across the southeastern united states into the western north atlantic late week into the first half of the weekend resulting in fresh easterly breezes.
the approximate shoreward edge of the gulf stream as of december 02...
58 nm south of dry tortugas light...on loggerhead key. 28 nm south of cosgrove shoal light...off the marquesas keys. 21 nm south of sand key light...off key west. 20 nm south of looe key...off big pine key. 15 nm south of sombrero key light...off marathon. 9 nm southeast of alligator reef light...off islamorada. 5 nm southeast of molasses reef light...off key largo. 4 nm east of carysfort reef light...off ocean reef.
gulf stream information courtesy of the naval oceanographic office.

FXUS62 KKEY 042000 AFDKEY

Area Forecast Discussion National Weather Service Key West FL 300 PM EST Mon Dec 4 2023

New DISCUSSION, MARINE, AVIATION

DISCUSSION
Issued at 300 PM EST Mon Dec 4 2023 Another very warm and humid day is ongoing across the Florida Keys. KBYX radar is quiet with GOES 16 Visible satellite imagery showing a shallow cloud line along the Island Chain with the fair weather cumulus not achieving much vertical growth. There are also some high level cirrus streaming from southwest to northeast across the Keys. Temperatures along the Island Chain are in the lower to mid 80s with dew points in the mid 70s. A weak frontal boundary is approaching the Keys resulting in marine platforms observing west to northwest winds near 5 knots with Island Chain communities observing near 5 mph.

FORECAST
A weak frontal boundary approaching the Keys will stall nearby for tonight and Tuesday resulting in northwest to north breezes initially veering to the north to northeast while freshening. Kept the PoP forecast the same as the previous package with 10% since we can't rule out a shower or two with the front nearby. This front will also bring slight relief in terms of the dew points and slightly cooler temperatures.

A second, much stronger front will push the aforementioned front through the Keys late Tuesday/early Wednesday which will bring much cooler temperatures, breezy conditions, and a significant dip in the dew points falling into the lower to mid 50s with upper 40s dew points not completely ruled out. The breezy conditions in combination with the cooler temperatures and drier air will give the air a crisp feeling to it. Also, make sure to tie down those Christmas decorations that might be able to easily be picked up by 15 to 20 mph wind speeds with gusts as high as 25 mph. Left 10% chance for showers Tuesday night and Wednesday with the passage of the front.

Wednesday night through Thursday night, expect mostly cloudy conditions as high level cirrus look to stream from southwest to northeast behind the front and surface high pressure slides across the southeastern United States. However, in terms of precipitation, it looks like it will remain dry through this time period, therefore, kept previous dry forecast. It will also be breezy with Thursday am being the coolest morning with temperatures of 60 to 65 degrees. There is the potential for some places to dip into the upper 50s also.

Then, Friday through Saturday night looks to feature breezy conditions at times as the high continues to slowly move east through the western North Atlantic. Moisture undulations around the southwestern periphery of the high will result in slight chances of showers through the period and slowly moderating temperatures.

Lastly, another front is poised to move through the Keys sometime Sunday through Monday. There remains uncertainty with this front in terms of timing and strength, therefore, recommend checking backing for updates as we approach the weekend. There is the potential that thunder may be added to the forecast in subsequent updates as most ingredients are lining up for this front to be more robust. Have chances for Sunday with slight chances Sunday night and Monday.

MARINE
Issued at 300 PM EST Mon Dec 4 2023 There are currently no watches, warnings, or advisories in effect across the Florida Keys coastal waters. From synopsis, gentle to moderate northwest to north breezes tonight become north to northeast late continuing through Tuesday in the wake of the first front. A second, much stronger cold front will push through the coastal waters late Tuesday or early Wednesday, with fresh northerly breezes expected in its wake. Strong high pressure will slide across the Southeastern United States into the western North Atlantic late week into the first half of the weekend resulting in waxing and waning moderate to fresh easterly breezes.

AVIATION
(18Z TAFS)
Issued at 300 PM EST Mon Dec 4 2023 VFR conditions will prevail at both island terminals through 18z Tuesday afternoon. Northwest to north winds in the wake of a frontal passage this afternoon will gradually shift to the north to northeast after 12z Tuesday morning.

PRELIMINARY POINT TEMPS/POPS
Key West 82 72 80 69 / 10 10 10 10 Marathon 84 72 80 66 / 10 10 10 10

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

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Mon -- 12:42 AM EST     1.91 feet High Tide
Mon -- 06:53 AM EST     Sunrise
Mon -- 08:29 AM EST     0.46 feet Low Tide
Mon -- 12:34 PM EST     Moonset
Mon -- 02:13 PM EST     1.34 feet High Tide
Mon -- 05:35 PM EST     Sunset
Mon -- 08:15 PM EST     0.95 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION

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Moser Channel (swingbridge)
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Mon -- 01:03 AM EST     0.60 knots Max Flood
Mon -- 04:04 AM EST     -0.00 knots Slack
Mon -- 06:53 AM EST     Sunrise
Mon -- 07:35 AM EST     -1.30 knots Max Ebb
Mon -- 11:12 AM EST     0.00 knots Slack
Mon -- 12:34 PM EST     Moonset
Mon -- 01:47 PM EST     0.86 knots Max Flood
Mon -- 05:16 PM EST     -0.00 knots Slack
Mon -- 05:35 PM EST     Sunset
Mon -- 08:27 PM EST     -1.16 knots Max Ebb
Mon -- 11:58 PM EST     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION

Moser Channel (swingbridge), Florida Current, knots

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