Sebastian Inlet to Jupiter Inlet 20-60 NM Marine Forecast
|This Afternoon...Southwest Winds 10 To 15 Knots Becoming South 20 To 25 Knots. Seas 2 To 3 Feet. A Dominant Period 6 Seconds. Chance Of Showers In The Morning. Scattered Thunderstorms. Showers In The Afternoon.|
|Tonight...Southwest Winds 20 To 25 Knots. Seas 4 To 6 Feet With Occasional Seas To 7 Feet. A Dominant Period 5 Seconds. Showers Likely In The Evening. Chance Of Thunderstorms. Chance Of Showers After Midnight.|
|Friday...Southwest Winds 20 Knots. Seas 4 To 6 Feet With Occasional Seas To 7 Feet. A Dominant Period 11 Seconds. Slight Chance Of Showers.|
|Friday Night...West Winds 15 To 20 Knots. Seas 4 To 6 Feet With Occasional Seas To 7 Feet. Slight Chance Of Showers.|
|Saturday...West Winds 15 To 20 Knots. Seas 3 To 5 Feet With Occasional Seas To 6 Feet. Slight Chance Of Showers.|
|Saturday Night...West Winds 10 To 15 Knots. Seas 3 To 4 Feet With Occasional Seas To 5 Feet.|
|Sunday...Northwest Winds 10 To 15 Knots. Seas 3 To 4 Feet With Occasional Seas To 5 Feet.|
|Sunday Night...North Winds 10 Knots. Seas 3 To 4 Feet With Occasional Seas To 5 Feet.|
|Monday...North Winds 5 To 10 Knots. Seas 2 To 3 Feet.|
| Seas are provided as a range of the average height of the highest one third of the waves, along with the occasional height of the average highest ten percent of the waves. Synopsis for Atlantic coastal waters from Flagler Beach to Jupiter Inlet out 60 nm - AMZ500|
327 AM EDT Thu Oct 28 2021
Light southerly winds and benign seas will rapidly increase as winds veer to southwest by mid-day ahead of a squall line, which will move through the local waters this afternoon and early evening. Winds and seas will be even higher near strong to severe storms. Boating conditions will remain hazardous through Friday night with strong southwest to west winds and seas building further well offshore. Conditions will slowly abate this weekend.
Gulf Stream Hazards: None.
The approximate location of the west wall of the Gulf Stream based on the Real Time Ocean Forecast System as of Tuesday, October 26th.
39 nautical miles east of Ponce Inlet.
30 nautical miles east of Port Canaveral.
23 nautical miles east of Sebastian Inlet.
15 nautical miles east of Fort Pierce Inlet.
10 nautical miles east of Saint Lucie Inlet.
| Area Forecast Discussion|
National Weather Service Melbourne FL
315am EDT Thu Oct 28 2021
...Strong to Severe Storms Expected later Today as a Squall Line Races Through the Area... ...Boating Conditions Will Rapidly Deteriorate from This Afternoon Through Friday... Current...Surface METAR and DRWP data show the weak high pressure ridge has moved offshore the SE CONUS/FL with light return SE-S flow already developing over the peninsula. GOES IR imagery shows a CS debris canopy emanating from the NE GOMEX MCS has overspread the peninsula. Current temps range from the L60s where winds have died off to the M-U60s where a light southerly drift exists. Temps are likely to rise a little through sunrise.
Regional doppler radar imagery shows a large cluster of convection covering eastern AL, the western FL panhandle, and extending S-W over the NE GOMEX. GOES IR imagery indicates an overall warming of cloud tops over the past several hours. Convection remains vigorous over/offshore the central panhandle, near the intersection of the SQLN and the northward moving warm front. A small band of showers extends farther SE along the warm front to just NW of Tampa Bay, lifting slowly NE with the boundary. Based on radar trends and the latest iteration of the HRRR, it appears that most of the precipitation will stay W-NW of lake County through 12Z/sunrise, though can't rule out a stray shower or two NW of I-4 between 6-8AM.
Today...Little change to the favorable synoptic setup for severe weather, so don't really need to review the specific wind, shear and instability parameters for the 4th time in as many nights. The last few runs of the HRRR (High-Resolution Rapid Refresh) have backed off on coverage of discrete warm sector convection ahead of the main SQLN, likely owing to a slightly less unstable air mass initially. Timing for the main band looks similar, reaching Lake/NW Volusia around 17Z/1PM, spreading rapidly east at 50-55mph, while propagating southward through the central peninsula during the afternoon through sunset. A few storms could still remain over the far SE CWA for an hour or so post-sunset, with some weaker shower band possibly redeveloping farther north through late evening. Any remaining activity should clear out around midnight behind passage of the occluded front.
Primary storm threats continue to be strong straight line winds within the SQLN and any cells or bands/segments just ahead of it, with one or two tornadoes also possible. Fast moving torrential downpours and frequent lightning strikes also expected within the stronger convection.
Warm/breezy with gusty S-SW winds developing. Max temps L-M80s NW of I-4 due to earlier onset of showers/storms, U80s across the central/ south. Steady west winds with minimal Cold Air Advection behind the occluded front tonight. Mins in the M-U60s except in NE Lake/NW Volusia Cos (L60s).
Friday...The strong cold front and associated line of thunderstorms is forecast to be south of the Treasure Coast by sunrise on Friday. Drier air filters in behind the front, with PWATs (Precipitable Waters) forecast to drop below 1" across the area. However, model soundings show all of the moisture concentrated between 700-850mb, and latest guidance is insistent on rather high rain chances for Friday, especially along/north of I-4. Looking at the synoptic picture, a very large cutoff low will be centered over the TN River Valley, with the base of the low across the northeastern Gulf Coast. A jet streak rounding the base of the low will maintain strong winds aloft, preventing significant vertical mixing of the narrow low-level moisture layer with the drier air above it.
This should allow scattered showers to develop in the eastern Gulf/Tampa Bay area and progress eastward across the peninsula. These showers will be racing northeastward at around 35-45 mph, and any downpours could be accompanied by gusty winds. As a result, looking at a 30-40 percent chance of rain from Melbourne northward, and a 20 percent chance for the Treasure Coast. No lightning storms are expected. Cooler across the norther areas as highs reach around 80 degrees, increasing to the mid 80s for the Treasure Coast.
Saturday - Sunday
.A few showers could linger into Saturday, though rain chances are only around 15 percent. Then, conditions should dry out on completely by Sunday as the large cutoff low moves into the western Atlantic causing a reinforcing cold front to move across Central FL on Saturday night. Breezy conditions continue into Saturday with west winds around 15 mph and some higher gusts.
As promised, the first real cool down of the fall season arrives this weekend. The initial surge of cooler air is expected for areas north of I-4 on Friday night into Saturday morning where lows drop into the upper 50s, and low 60s elsewhere. For Saturday afternoon, highs remain in the mid/upper 70s from Kissimmee to Titusville northward, and around 80 degrees from Melbourne south.
Cooler still for Saturday night into Sunday morning as lows drop into the mid to upper 50s for most, except low 60s for the immediate Space/Treasure Coast. Highs on Sunday in the upper 70s and up to around 80 degrees in the Treasure Coast.
Monday - Wednesday
High pressure builds across the region for the first half of next week, maintaining mostly dry conditions. Near normal temperatures are forecast with highs in the low 80s, and overnight lows in the low to mid 60s.
Today - Tonight
Current benign conditions over the local waters (winds <10kt/2-3ft seas) belie the rapid deterioration expected later today-tonight. Expect a rapid increase in S-SW winds to about 20kt by mid-day with SQLN passage across the waters north of the Cape about 2-5PM and to the south 5-9PM. Winds shift to more WSW and increase further (20-25kt) behind occluded frontal passage. Offshore component should keep peak seas at about 6ft well offshore though can't rule out occasional sets around 7ft out toward 50-60nm. SCA (Small Craft Advisory) will co into effect at 1pm today for all of the local Atlantic waters, and continue tonight into Friday.
Friday-Saturday...Hazardous boating conditions continue Friday as tight pressure gradient maintains SW/WSW winds 20-25 knots behind the cold front. Seas 4-6 feet nearshore and up to 7 feet offshore. A Small Craft Advisory remains in effect through Friday night. Boating conditions improve a bit on Saturday, however small craft will probably need to exercise caution due to west winds around 15-20 knots. Seas 3-5 feet.
Sunday-Monday...A reinforcing cold front will move through the area Saturday night, causing winds to veer NW at 10-15 knots on Sunday. Seas diminish to 2-3 feet nearshore and 4-5 feet offshore. High pressure builds into the region on Monday with northeast winds around 10 knots and seas 2-3 feet.
NOAA Melbourne FL Office: Watches - Warnings - Advisories
FL...None. AM...Small Craft Advisory from 1pm this afternoon to 8pm EDT Friday for Flagler Beach to Volusia-Brevard County Line 0-20 nm- Sebastian Inlet to Jupiter Inlet 0-20 nm-Volusia-Brevard County Line to Sebastian Inlet 0-20 nm.
Small Craft Advisory from 1pm this afternoon to 8am EDT Saturday for Flagler Beach to Volusia-Brevard County Line 20-60 nm-Sebastian Inlet to Jupiter Inlet 20-60 nm-Volusia- Brevard County Line to Sebastian Inlet 20-60 nm.