Jupiter Inlet to Deerfield Beach, FL out 20nm Marine Forecast
|Today...South Southwest Winds 10 To 20 Knots With Gusts To Around 30 Knots. Seas 2 To 4 Feet With Occasional Seas To 5 Feet. Period 5 Seconds. Intracoastal Waters A Moderate Chop. Showers Likely And Chance Of Thunderstorms.|
|Tonight...Southwest Winds 15 To 20 Knots With Gusts To Around 25 Knots Along The Coast To Southwest 20 To 25 Knots With Gusts To Around 30 Knots In The Gulf Stream. Seas 2 To 4 Feet With Occasional Seas To 5 Feet Along The Coast And 4 To 6 Feet With Occasional To 8 Feet In The Gulf Stream. Period 5 Seconds. Intracoastal Waters A Moderate Chop. Showers Likely And Chance Of Thunderstorms.|
|Friday...West Southwest Winds 15 To 20 Knots With Gusts To Around 25 Knots. Seas 3 To 5 Feet With Occasional Seas To 6 Feet. Period 5 Seconds. Intracoastal Waters A Moderate Chop. Chance Of Showers And Thunderstorms In The Morning, Then Slight Chance Of Showers And Thunderstorms In The Afternoon.|
|Friday Night...West Southwest Winds 15 To 20 Knots With Gusts To Around 25 Knots. Seas 3 To 5 Feet With Occasional Seas To 6 Feet. Period 5 Seconds. Northeast Swell 3 Feet. Intracoastal Waters A Moderate Chop. Slight Chance Of Showers.|
|Saturday...West Southwest Winds 15 To 20 Knots With Gusts To Around 25 Knots. Seas 3 To 5 Feet With Occasional Seas To 6 Feet. East Northeast Swell 3 Feet In The Afternoon. Intracoastal Waters A Moderate Chop. Slight Chance Of Showers In The Afternoon.|
|Saturday Night...West Northwest Winds 5 To 15 Knots Along The Coast To West 10 To 15 Knots With Gusts To Around 20 Knots In The Gulf Stream. Seas 3 To 5 Feet With Occasional Seas To 6 Feet. North Northeast Swell 3 Feet. Intracoastal Waters A Light Chop.|
|Sunday...North Winds 5 To 10 Knots Along The Coast To North Northwest 10 To 15 Knots In The Gulf Stream. Seas 2 To 4 Feet With Occasional Seas To 5 Feet. Intracoastal Waters A Light Chop.|
|Sunday Night...North Northeast Winds Around 10 Knots. Seas 2 To 4 Feet With Occasional Seas To 5 Feet. Intracoastal Waters A Light Chop.|
|Monday...Northeast Winds 10 To 15 Knots. Seas 2 To 4 Feet With Occasional Seas To 5 Feet. Intracoastal Waters A Moderate Chop.|
| AMZ600: Synopsis for Jupiter Inlet to Ocean Reef FL out to 60 nm and for East Cape Sable to Bonita Beach FL out to 60 nm|
529 AM EDT Thu Oct 28 2021
Conditions will rapidly deteriorate today as a strong frontal boundary approaches the region from the west. Strong to severe thunderstorms will be possible ahead of main front, while breezy conditions will accompany the passage of this system. Small craft advisories in place for all of the Gulf and Atlantic waters through at least Friday night. Extensions may be necessary.
Gulf Stream Hazards: Strong to severe thunderstorms possible and sustained winds of 20 to 25 kt. Seas 4 to 6 feet.
The approximate location of the west wall of the Gulf Stream as of Oct 28, 2021 at 1200 UTC...
- 14 nautical miles east of Fowey Rocks.
- 15 nautical miles east southeast of Port Everglades.
- 12 nautical miles east northeast of Lake Worth.
- 13 nautical miles east of Jupiter Inlet.
| Area Forecast Discussion|
National Weather Service Miami FL
946am EDT Thu Oct 28 2021
A strong cold front continues to push slowly southward across Northern and Central Florida this morning. South Florida will remain in the warm sector throughout the majority of the day with dewpoints remaining in the upper 70s across the region. Out ahead of this front, scattered to numerous showers and thunderstorms will develop as the day progresses. Severe weather parameters over the region remain favorable for isolated severe storm development this afternoon. From the 12Z MFL sounding, DCAPE values came in around 1200 J/KG, SRH 0 to 3 KM came in at 129 m2/s2 and 500 mb temps are around -7.5C. PWAT (Precipitable Water) values also came in at 1.83 inches and these are forecasted to increase to exceed 2 inches as today progresses. As thunderstorms develop, this will lead to the possibility of heavy downpours resulting in localized flooding especially across the metro areas this afternoon into tonight. The big question will be how fast this front continues to press southward. With the latest hi res guidance trending slower, the amount of instability will be less as the peak heating of the day will have passed. The greatest chances of strong to severe thunderstorms remains across the Lake Okeechobee region as the front will be closest that area this afternoon. All of these factors and parameters will continue.nue to be monitored as the event unfolds.
(Issued 731am EDT Thu Oct 28 2021)
A frontal boundary will approach South Florida as the day progresses. Winds will quickly increase out of the southwest by the middle of the morning and it will be gusty at times this afternoon. Chances of showers and thunderstorms will increase across South Florida from west to east later this morning and these chances will remain in place through tonight. MVFR (Marginal Visual Flight Rules) or even IFR conditions will be possible in showers and thunderstorms.
(Issued 314am EDT Thu Oct 28 2021)
.Strong to Isolated Severe Storms Possible Today into Tonight
.Deteriorating Beach/Marine Conditions Today into Weekend... Short Term - Today Through Friday
Thursday into Thursday Night:
The strongest cold front of the ever-so-young Fall season is on approach to the stifling Sunshine State. A deepening low pressure system will amplify as it moves across the central CONUS and towards the Appalachians today while also becoming negatively tilted. For us here in South FL, the associated warm front is expected extend from the triple point (which remains well to the north of the region) and move from south to north across the CWA throughout the morning into early afternoon hours. This will keep South FL in the warm sector, with forecast dewpoints in the upper- 70s to near 80 and temperatures approaching 90 degrees (close to breaking a record for Miami). Deep, moisture-laden tropical moisture will continue.nue to pump into the region thanks to southerly low-mid level flow and decent WAA, with forecast PW's forecast to exceed 2 inches (about 2.0 to 2.3 standard deviations above the climatological mean for this time of year, or in the 97.5 to 99th percentile). This will allow for the possibility of heavy downpours. As multiple rounds of showers and thunderstorms move across the area, localized flooding is possible, mainly over the urban and low-lying areas across the region.
What is tricky with the short term forecast is the timing of precipitation, how many lines of storms march through the area, and if dry lulls are forecast. Why? Well, CAMs are in a slight tiff with one another. Most guidance agrees that the majority of convection will occur with the cold FROPA and more linear in nature. Too early to know if a squall line develops but it can not be ruled out. Ahead of the front, drier periods of weather may be possible, however with South FL in the warm sector, that looks less and less likely. With that said, some of the CAMs, including HRRR (High-Resolution Rapid Refresh) and NAM, suggest that discrete cells will be possible, mainly during the evening into overnight hours as the front rapidly pushes through.
Instability is another question for today, i.e. if dry pockets and gaps in cloud coverage occur vs. scattered showers and storms with South FL being in the warm sector. Diving into forecast severe weather parameters... -CAPE near 1500 J/kg -0 to 1km SRH near 110 m2/s2 and 0 to 3 km SRH near 120 m2/s2 -DCAPE near 1200 J/kg -500 mb temps near -6 to -7 (albeit on the warmer side) -0 to 3km bulk shear ranging from 25 to 35 kt -Mid-level jet in vicinity of South FL (though should remain to the north)
Of course, if these parameters come into fruition, strong wind gusts, hail (if strong and sustained updrafts were to develop), and an isolated tornado are possible. Otherwise, storms may have a tendency to eventually congeal as they move eastward across the CWA with winds becoming the overarching hazard.
Increasing Probability of Precipitation today from west to east, with the east coast potentially seeing a strong line of storms during the overnight hours. Increasing winds towards the latter half of the day as the pressure gradient tightens.
A few lingering showers and storms will be possible Friday as the cold front continues to push southward. Rain chances will decrease from west to east as the day progresses, with highest Probability of Precipitation during the morning hours. Otherwise, drier air filters in to the region. Not much Cold Air Advection Friday. Fans of cooler temps, see long term discussion... Long Term - Friday night through Wednesday
A cold core upper low will continue.nue to sit over the Tennessee/Ohio River Valleys at the start of the long term. Cold air advection will continue and in fact may increase a bit later Saturday as a secondary frontal boundary surges southward through the state as the upper level trough amplifies further. With the front there could be some lower clouds and perhaps some light rainfall, however, Quantitative Precipitation Forecast looks extremely light likely due to the very dry continental airmass that will filter into the region behind the initial front.
With the anomalously lower H5 heights, below average temperatures can be expected this weekend, before the trough quickly gets punted east over the western Atlantic. Although the upper heigheights and thicknesses reflect a well below average temperature regime, there will be some moderation with land/sea contrast. Though, overnight Saturday winds will become lighter, which may help interior sections near Lake Okeechobee (the cooler areas) drop into the upper 50s. One limiting factor would be residual low level cloud cover that may linger evident by the continued cyclonic curvature within the surface wind field.
Aloft, the dry northwesterly flow this weekend will quickly transition back to a more active (and more moist) southwesterly flow. The westerly winds at the surface will also shift to an easterly direction as high pressure settles across the Wiregrass region of SE AL/SW GA. With the quick moderation in boundary layer moisture, globals are pinging a Quantitative Precipitation Forecast signal (albeit weak) so carried some lower end POPs toward the end of the period. Again, with the moist return flow setting up, temperatures will also begin to rebound by early next week back to seasonal averages.
VFR conditions early this morning will deteriorate into the MVFR (Marginal Visual Flight Rules) range late morning/early afternoon as a cold front approaches South FL. Widespread MVFR (Marginal Visual Flight Rules) and local IFR CIGs/VIS likely as SHRA/TSRA plague the area, especially during the afternoon and evening hours. East coast terminals may see IFR conditions again during the overnight hours, so may need to extend current PROB30 or add additional PROB30 groups for overnight hours with later TAF cycles across east coast terminals. Lgt/vrb winds thisam giving way to breezy SW winds by 15Z, with gusts up to 25kt possible. Higher gusts possible in/near TSRA. Flow becomes more W late tonight. Short-fused AMDs and addition of TEMPOs likely today as confidence on timing and coverage grows with TS/SHRA (rain showers) associated with cold front.
Conditions will rapidly deteriorate today as a strong cold frontal boundary approaches the region from the northwest. Strong to severe thunderstorms will be possible ahead of the front, while breezy conditions will accompany the passage of this system. A Small Craft Advisory is in place for all Gulf waters and Atlantic waters today through at least Friday night. Extension may be necessary, especially for Gulf waters where elevated seas greater than 6 feet persist. Small Craft Exercise Caution in place for the Biscayne Bay waters and Lake Okeechobee.
Latest models are still showing that the breakers along the west coast beaches of South Florida could still get up to around 6 feet Friday night into Saturday with the westerly swells around 2 feet persisting into the weekend. Atlantic waters could see northeasterly swells of 2 to 4 feet during the weekend as well. Will continue to monitor this to see if a High Surf Advisory will be needed for portions of the west coast beaches of South Florida for Friday night into Saturday.
BEACHES... A strong cold front will move across the region today into tonight. As the winds shift around to the WNW, a high risk of rip currents will develop across the Gulf Coast beaches for the end of the week and into the upcoming weekend. At the Atlantic coast beaches, a moderate risk of rip currents will develop as the front moves through and it will remain elevated through the upcoming weekend. The Palm Beaches may need to be upgraded to a high risk Friday into the weekend as building NE swell brushes the coast.
Here are the forecast and record highs for the east coast sites for Thursday (10/28/2021):
HIGH RECORD YEAR AVE +-
WEST PALM BEACH 88 91 IN 1972 83 5 FORT LAUDERDALE 88 92 IN 1925 84 4 MIAMI 89 90 IN 2019 85 4
NOAA Miami FL Office: Watches - Warnings - Advisories
FL...High Rip Current Risk through Saturday evening for FLZ069.
AM...Small Craft Advisory from 1pm this afternoon to 8pm EDT Friday for AMZ610-630-650-651-670-671.
GM...Small Craft Advisory until 8am EDT Saturday for GMZ656-657-676.