Marine Weather Net

Straits of Florida from Halfmoon Shoal to 20 NM west of Dry Tortugas out 20 NM Marine Forecast


OVERNIGHT

E
WINDS
10 - 15
KNOTS

THURSDAY

SE
WINDS
10 - 15
KNOTS

THURSDAY NIGHT

ESE
WINDS
5 - 10
KNOTS

FRIDAY

ESE
WINDS
10
KNOTS

The Marine Weather Forecast In Detail:
GMZ055 Forecast Issued: 1025 PM EDT Wed Aug 04 2021

Overnight...East Winds 10 To 15 Knots, Becoming Southeast. Seas Seas Building To 2 To 3 Feet. Isolated Showers And Thunderstorms.
Thursday...Southeast Winds 10 To 15 Knots, Decreasing To 5 To 10 Knots. Seas Subsiding To 1 To 2 Feet. Scattered Showers And Isolated Thunderstorms.
Thursday Night...East To Southeast Winds 5 To 10 Knots, Increasing To Near 10 Knots. Seas 1 To 2 Feet. Isolated Showers And Thunderstorms.
Friday...East To Southeast Winds Near 10 Knots, Decreasing To 5 To 10 Knots. Seas 1 To 2 Feet. Scattered Showers And Isolated Thunderstorms.
Friday Night...East To Southeast Winds 5 To 10 Knots, Increasing To 10 To 15 Knots. Seas Building To 2 To 3 Feet. Isolated Showers And Thunderstorms.
Saturday...East To Southeast Winds Near 10 Knots. Seas Around 2 Feet. Scattered Showers And Isolated Thunderstorms.
Saturday Night...East Winds Increasing To 10 To 15 Knots. Seas 2 To 3 Feet. Isolated Showers And Thunderstorms.
Sunday...East Winds Near 10 Knots. Seas Around 2 Feet. Scattered Showers And Isolated Thunderstorms.
Sunday Night And Monday...East Winds 10 To 15 Knots. Seas 2 To 3 Feet. Scattered Showers And Isolated Thunderstorms.
Monday Night...East Winds Near 15 Knots. Seas Building To 2 To 4 Feet. Isolated Showers And Thunderstorms.
SHARE THIS PAGE:           
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas: GMZ005
1025 PM EDT Wed Aug 4 2021

A ridge axis in the vicinity of the island chain will lift northward into Central Florida over the next several days. East to southeast light breezes will tend to freshen in the overnight to early morning periods, occasionally becoming moderate. Breezes will freshen early next week as the ridge axis broadens and lifts further northward. Near-normal rain and thunder chances are expected tonight through at least Monday.

Gulf Stream
The Approximate Shoreward Edge of the Gulf Stream as of August 05, 2021...
- 39 NM South of Dry Tortugas Light...on Loggerhead Key.
- 8 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
- 4 NM South of Sand Key Light...off Key West.
- 8 NM South of Looe Key...off Big Pine Key.
- 9 NM South of Sombrero Key Light...off Marathon.
- 9 NM Southeast of Alligator Reef Light...off Islamorada.
- 4 NM Southeast of Molasses Reef Light...off Key Largo.
- 1 NM East of Carysfort Reef Light...off Ocean Reef.
Area Forecast Discussion
National Weather Service Key West FL
956pm EDT Wednesday August 4 2021

A ridge axis currently is extending across the Florida Keys and South Florida, which is supporting gentle breezes across the coastal waters and the island chain. Convection across South Florida and the Keys has mostly dissipated, leaving us with partly to mostly cloudy skies from the remnant upper-level cloud cover that came off earlier convection. This cloud cover will continue to deteriorate and leave us with partly cloudy skies. KBYX is mostly echo-free, with only a few light showers in the Straits of Florida that are rapidly falling apart. The 00Z KEY RAOB (Radiosonde Observation or Upper-Air Observation) recorded a layer of drier air beginning around 890 mb. This, combined with an inversion around the same height, has helped keep any shower activity shallow this evening. Temperatures across the island chain are currently in the lower to mid 80s, with dewpoints in the mid 70s. The ridge axis will shift northward overnight, allowing for another wind surge like we experienced last night with breezes becoming light to moderate. Have nudged Probability of Precipitation down to a slight chance for tonight, which is in line or even slightly above guidance. Otherwise, the forecast looks to be on track and no other changes are needed.

Marine
No watches, warnings, or advisories are in effect for the Florida Keys coastal waters. From synopsis, A ridge axis in the vicinity of the island chain will lift northward into Central Florida over the next several days. East to southeast light breezes will tend to freshen in the overnight to early morning periods, occasionally becoming moderate. Breezes will freshen early next week as the ridge axis broadens and lifts further northward. Near-normal rain and thunder chances are expected tonight through at least Monday.

Climate
On this day in 1894, both the daily record low temperature of 68F and the daily record rainfall of 2.74" were recorded in Key West. The low temperature of 68F is also tied for the coldest temperature ever recorded in August. Rainfall records date back to 1871 and temperature records date back to 1872.

NOAA Key West FL Office: Watches - Warnings - Advisories
FL...None. GM...None.