Hawk Channel from Seven Mile Bridge to Halfmoon Shoal out to the reef Marine Forecast
|Tonight...Southwest To West Winds 5 To 10 Knots, Becoming South After Midnight. Seas Around 1 Foot. Nearshore Waters Smooth To A Light Chop. Isolated Showers And Thunderstorms.|
|Tuesday...South Winds 5 To 10 Knots, Becoming East To Southeast Near 5 Knots. Seas Around 1 Foot. Nearshore Waters Smooth To A Light Chop, Becoming Smooth. Scattered Showers And Thunderstorms.|
|Tuesday Night...East To Southeast Winds 5 To 10 Knots, Becoming Southeast Near 10 Knots After Midnight. Seas 1 To 2 Feet. Nearshore Waters Smooth To A Light Chop, Becoming A Light Chop. Scattered Showers And Thunderstorms.|
|Wednesday...East To Southeast Winds 5 To 10 Knots. Seas 1 To 2 Feet. Nearshore Waters Smooth To A Light Chop. Scattered Showers And Thunderstorms.|
|Thursday...East To Southeast Winds 5 To 10 Knots. Seas 1 To 2 Feet. Nearshore Waters Smooth To A Light Chop. Scattered Showers And Thunderstorms.|
|Thursday Night And Friday...East To Southeast Winds Near 10 Knots. Seas 1 To 2 Feet. Nearshore Waters A Light Chop. Scattered Showers And Thunderstorms.|
|Friday Night...East Winds 10 To 15 Knots. Seas 1 To 2 Feet. Nearshore Waters A Light To Moderate Chop. Scattered Showers And Thunderstorms.|
|Saturday...East Winds 10 To 15 Knots. Seas 1 To 2 Feet. Nearshore Waters A Light To Moderate Chop. Scattered Showers And Thunderstorms.|
Synopsis for Keys coastal waters from Ocean Reef to Dry Tortugas: GMZ005|
422 PM EDT Mon Aug 3 2020
A broad and ill-defined trough will move west across the Keys waters on Tuesday, bringing a slow transition from light southwest to southeast winds. A dull high pressure ridge will build across the Florida Peninsula on Wednesday, then sharpen and strengthen on Thursday and Friday. By Friday and Saturday, gentle to moderate easterly breezes will prevail.
The Approximate Shoreward Edge of the Gulf Stream as of August 1...
- 54 NM South of Dry Tortugas Light...on Loggerhead Key.
- 23 NM South of Cosgrove Shoal Light...off the Marquesas Keys.
- 11 NM South of Sand Key Light...off Key West.
- 4 NM South of Looe Key...off Big Pine Key.
- 4 NM South of Sombrero Key Light...off Marathon.
- 4 NM Southeast of Alligator Reef Light...off Islamorada.
- 4 NM Southeast of Molasses Reef Light...off Key Largo.
- 3 NM East of Carysfort Reef Light...off Ocean Reef.
Area Forecast Discussion|
National Weather Service Key West FL
338pm EDT Monday August 3 2020
The main forecast highlight will be a rise to above normal rain chances by late Tuesday, with the wetter-than-normal period continuing until Thursday night.
(Tonight through Thursday)
At the surface, a broad col in the flow is located somewhere southwest of Andros Island this afternoon, with a broad area of convergence extending north from there. As evidence, southeast winds are currently observed in the southeast Bahamas, while southwest winds are observed here in the Keys. Within this area of convergence, MIMIC PW imagery shows a north-south axis of extremely moist air, with Precipitable Water (PW) values of 2.1" to 2.3" in the axis. So this broad area of convergence off to our east is the main larger-scale focus for lift and and deeper moisture.
It will move little through tonight. It is basically stuck under southerly flow aloft between a strong subtropical high out near Bermuda, and an unseasonably south-digging mid-latitude trough in the Lower Mississippi Valley. It will finally budge slowly westward across the forecast domain on Tuesday and Wed, exiting west into the Gulf on Thu. In its wake, a strong subtropical high will first nose into the Bahamas on Tue, then nudge across the FL Peninsula on Wed, finally strengthening and sharpening on Thu. During this time, above normal rain chances are forecast across the Keys, with the official forecast reflecting peak chances coming on Wednesday.
(Thursday night through next Monday)
A most seasonable pattern will return from Friday through Monday. The subtropical high extending from Bermuda to the Bahamas will expand westward as a ridge across the Florida Peninsula, bringing seasonable deep- layer east-southeast flow across the Keys. PW values will dry out back to near normal. The prevalence of high pressure means we will rely on mesoscale focusing mechanisms, such as daytime heating on nearby land masses. Have held close to climo Probability of Precipitation from Thursday night through Monday.
A broad and ill-defined trough will move west across the waters on Tuesday, marking a slow transition from southwest back to southeast winds. This transition will come with periods of light and variable winds.
A dull ridge will start to build west across the FL Peninsula on Wed, then sharpen and strengthen on Thu. It will persist into the weekend. By late in the week, this will lead to gentle to moderate easterly breezes.
NOAA Key West FL Office: Watches - Warnings - Advisories