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GMZ043 Expires:202312111515;;276201 Fzus52 Kkey 110906 Cwfkey
coastal waters forecast for the florida keys national weather service key west fl 406 am est Mon dec 11 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.
gmz042-043-111515- 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- 406 am est Mon dec 11 2023
.small craft should exercise caution for increasing winds...
.small craft advisory likely will be required tonight...
Today..West to northwest winds near 10 knots early, becoming northwest to north and increasing to 15 to 20 knots during the morning. Then winds becoming north and decreasing to near 15 knots in the afternoon. Seas building to 2 to 3 feet. NEarshore waters becoming choppy.
Tonight..North to northeast winds 15 to 20 knots, increasing to near 20 knots. Seas 2 to 4 feet, building to 3 to 4 feet. NEarshore waters choppy, becoming rough.
Tuesday..Northeast winds near 20 knots. Seas 3 to 5 feet. NEarshore waters rough. Isolated showers in the afternoon.
Tuesday night..Northeast winds near 20 knots. Seas 3 to 5 feet. NEarshore waters rough. Scattered showers.
Wednesday..Northeast to east winds near 20 knots. Seas 3 to 5 feet. NEarshore waters rough. Numerous showers and isolated Thunderstorms.
Wednesday night..Northeast winds 15 to 20 knots. Seas 2 to 4 feet. NEarshore waters choppy. Numerous showers.
Thursday..Northeast to east winds near 20 knots, increasing to 20 to 25 knots. Seas 3 to 5 feet. NEarshore waters rough, becoming very rough. Numerous showers.
Thursday night..Northeast to east winds near 25 knots. Seas 4 to 6 feet. NEarshore waters extremely rough. Numerous showers.
Friday..East winds 20 to 25 knots. Seas 4 to 6 feet. NEarshore waters very rough. Scattered showers.
Friday night..East winds near 20 knots. Seas 4 to 6 feet. NEarshore waters rough. Scattered showers.

GMZ005 Synopsis For Keys Coastal Waters From Ocean Reef To Dry Tortugas 406 Am Est Mon Dec 11 2023
Synopsis..A cold front will continue pressing southeastward through the florida keys coastal waters early this morning. As a result, expect rapidly freshening northwest to north breezes as the front moves through. Then, a large area of high pressure across the eastern united states will maintain fresh to strong breezes Monday night through Friday well after the short blast of cooler and drier air. There is also the potential for a period of near-gale breezes (28-33 knots) late this week.
the approximate shoreward edge of the gulf stream as of december 09...
45 nm south of dry tortugas light...on loggerhead key. 15 nm south of cosgrove shoal light...off the marquesas keys. 10 nm south of sand key light...off key west. 11 nm south of looe key...off big pine key. 17 nm south of sombrero key light...off marathon. 21 nm southeast of alligator reef light...off islamorada. 11 nm southeast of molasses reef light...off key largo. 5 nm east of carysfort reef light...off ocean reef.
gulf stream information courtesy of the naval oceanographic office.

FXUS62 KKEY 110917 AFDKEY

Area Forecast Discussion National Weather Service Key West FL 417 AM EST Mon Dec 11 2023

New DISCUSSION, MARINE, AVIATION

DISCUSSION
Issued at 417 AM EST Mon Dec 11 2023 KBYX radar shows the cold front moving southeastward through the deep Gulf waters and the nearshore waters to the west and north of the Lower Keys. The cold front is being accompanied by a few brief sprinkles along with an increase in winds. Marine platforms are currently observing northwest to north winds of 10 to 15 knots with the Island Chain observing 10 to 15 mph. Temperatures across the Island Chain are currently in the lower 70s with dew points near 70 degrees.

FORECAST
After the passage of the cold front early this morning, expecting a dry day with breezy conditions, especially for the Middle and Lower Keys. We did decide to go with a split of the zones as current thinking is the Upper Keys just miss out on the breezy conditions at least for the today period. Also, temperatures may struggle to rise much from where they start out this morning due to the northerly breezes and a fair amount of cloud cover.
Therefore, kept highs in the lower 70s for today for only a rise of a degree or two expected.

From Monday night on through late week, a strong anticyclone over the Southeastern United States will mostly fluctuate in strength and placement for the duration of the week. This will result in a prolonged breezy to at times windy period for the Keys. Late week, there may be the potential for Wind Advisories, though, current thinking is this will be less likely based on the northeast wind direction and magnitudes just below thresholds. Also, moisture undulations are expected on the anticyclones southern periphery resulting in increasing rain chances, especially for Tuesday night through at least Thursday night. However, some model guidance is showing the wet period persisting even well past Thursday night, therefore, expect the PoP chances to continue to fluctuate in subsequent updates. For now, adding timing on Tuesday with 10% for Tuesday afternoon, kept the 40% Tuesday night, but increased Wednesday through Thursday night to 60%. Also, kept the risk for thunder in on Wednesday, though, some latest guidance is suggesting thunder may be needed in other periods mid to late week. There are also indications some of this rainfall mid to late week may be heavy but held off on any locally heavy rainfall wording for now. The WPC- Weather Prediction Center does currently highlight the Keys in a marginal risk for heavy rainfall on Friday.

Friday through the weekend, model guidance remains in disagreement on where and when a surface low will form in the Gulf which will have implications on the wind and PoP forecast.
Therefore, due to the continued uncertainty here, recommend checking back frequently for updates as the unsettled weather continues for the Keys.

MARINE
Issued at 417 AM EST Mon Dec 11 2023 Small Craft Advisory is in effect for the deep Gulf waters, the Gulf of Mexico waters from west end of the Seven Mile Bridge to Halfmoon Shoal out to 5 fathoms, and the western half Straits of Florida. Small Craft Should Exercise Caution for increasing winds (SCEC) are headlines today for all other marine zones with Small Craft Advisory Likely Will be Required tonight also headlined.
Small Craft Advisory conditions are expected to persist through much of the upcoming week with a period of potential near-gale breezes (28-33 knots) sometime late week. Therefore, a Gale Watch or Gale Warning may be required. From synopsis, a cold front will continue pressing southeastward through the Florida Keys coastal waters early this morning. As a result, expect rapidly freshening northwest to north breezes as the front moves through. Then, a large area of high pressure across the eastern United States will maintain fresh to strong breezes Monday night through Friday well after the short blast of cooler and drier air. There is also the potential for a period of near-gale breezes (28-33 knots) late this week.

AVIATION
(06Z TAFS)
Issued at 417 AM EST Mon Dec 11 2023 A passing cold front resulted in a complicated forecast. VFR conditions will give way to brief MVFR ceilings after the front transits across the terminals. While IFR cloud bases are possible, statistical guidance dropped IFR ceilings and such are left out of the TAF due to low confidence. North-northwesterly breezes will dominate after sunrise, but winds may veer north- northeasterly after 12/00 UTC.

CLIMATE
On this day in 1962, the daily record cold high temperature of 60F was recorded in Key West. Temperature records for Key West date back to 1872.

PRELIMINARY POINT TEMPS/POPS
Key West 72 66 76 70 / 10 0 10 40 Marathon 72 65 75 71 / 0 0 10 40

KEY WATCHES/WARNINGS/ADVISORIES
FL...None.
GM...Small Craft Advisory until 5 PM EST this afternoon for GMZ033>035-044-054-055-074-075.

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Conch Key
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Mon -- 01:41 AM EST     -0.08 feet Low Tide
Mon -- 05:37 AM EST     Moonrise
Mon -- 06:57 AM EST     Sunrise
Mon -- 08:06 AM EST     1.11 feet High Tide
Mon -- 12:50 PM EST     0.37 feet Low Tide
Mon -- 04:25 PM EST     Moonset
Mon -- 05:35 PM EST     Sunset
Mon -- 07:00 PM EST     1.80 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Conch Key, eastern end, Florida, Tide feet

Long Key Viaduct
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Mon -- 01:16 AM EST     -1.48 knots Max Ebb
Mon -- 04:37 AM EST     0.00 knots Slack
Mon -- 05:36 AM EST     Moonrise
Mon -- 06:57 AM EST     Sunrise
Mon -- 07:32 AM EST     1.27 knots Max Flood
Mon -- 11:06 AM EST     -0.00 knots Slack
Mon -- 02:07 PM EST     -1.17 knots Max Ebb
Mon -- 04:25 PM EST     Moonset
Mon -- 05:16 PM EST     0.00 knots Slack
Mon -- 05:35 PM EST     Sunset
Mon -- 07:29 PM EST     0.74 knots Max Flood
Mon -- 10:10 PM EST     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION

Long Key Viaduct, Florida Current, knots

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Key West, FL,