Area Forecast Discussion
Issued by NWS Melbourne, FL
Issued by NWS Melbourne, FL
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812 FXUS62 KMLB 131935 AFDMLB Area Forecast Discussion National Weather Service Melbourne FL 335 PM EDT Thu Jun 13 2024 ...New DISCUSSION, MARINE... Key Messages... -Scattered to numerous showers and storms through this evening, with locally heavy rainfall and a few strong storms still possible. -Higher rain chances continue Friday and Saturday, with locally heavy rainfall still a concern. -Rain chances continue, but are forecast to gradually decrease into late weekend and next week as winds become onshore and breezy. .DISCUSSION... Issued at 335 PM EDT Thu Jun 13 2024 Currently-Tonight...Area of low pressure, designated Invest 90L, off the northeast FL coast will continue to shift slowly northeast into tonight. Trough extending from this low has shifted southward toward the Orlando area, with winds out of the N/NE near and north of this area. While farther south, S/SW flow continues to pull in more moisture, which led to higher coverage of showers and storms across Okeechobee County and the Treasure Coast. This activity has continued to weaken as it shifts eastward and offshore. Farther north, convection will continue to increase through late afternoon where greater daytime heating is ongoing. Scattered to numerous showers and storms will primarily develop along any boundaries, including the lingering trough axis, the inland moving sea breeze across Volusia County, and from any differential heating boundaries generated by the increased cloud cover across southern portions of the area, and partly sunny skies to the north. Persistent or repeated rounds of showers and storms will still pose a threat of heavy rainfall, with totals around 1-3" and locally higher totals of 4 inches or more possible. Additional storm threats will include occasional to frequent lightning strikes and strong gusty winds to 40 to 45 mph. Scattered showers and storms will linger into the evening, but gradually diminish by late evening and toward midnight. CAM guidance indicates fairly dry conditions overnight. However, some increasing shower/storm potential will occur later tonight toward daybreak Friday across Okeechobee County and the Treasure Coast. Remaining mild and humid with lows in the low to mid 70s. Friday-Saturday...Invest 90L will continue to lift N/NE and remain offshore the eastern U.S. coast, and may strengthen some through early this weekend. As it does so, a weak frontal boundary will shift into northern portions of central FL, and gradually fade into the weekend. There remains some differences in the models with how much drier air filters into the north through this period, with the GFS drier than the ECMWF. Have trended PoPs down to 60-70 percent into tomorrow, and ranging from 40-50 percent north of Orlando and 60-70 percent south on Saturday. Steering winds weaken and deeper moisture across southern portions of central FL will keep the potential for locally heavy rainfall in the forecast. WPC maintains a Marginal Risk for Excessive Rainfall in the forecast for both days, especially focused over southern sections of the area. Locally heavy rainfall of 1-3 inches will be possible with any slow moving or repeated rounds of showers and storms. Other storm hazards will continue to be occasional to frequent lightning strikes and gusty winds. Afternoon high temperatures forecast to be a little warmer across northern portions of east central FL both days, with highs in the low to mid 90s and in the upper 80s to the south. Lingering humid conditions will lead to peak heat index values around 100-105. Overnight lows remain in the low to mid 70s. Sunday-Wednesday...High pressure building off the eastern U.S. coast will lead to winds becoming onshore and increasing into next week. This will shift deeper moisture southwest of the area. However, models continue to be in disagreement through early week, with the ECM showing higher rain chances than the GFS due to the GFS showing drier air moving into the area. Therefore some uncertainty remains in overall rain chances, but have PoPs trending downward from 50-60 percent on Monday and then around 50 percent Tuesday through Wednesday. Temperatures will be seasonable through the period, with afternoon highs in the upper 80s to low 90s, and lows remaining in the 70s. && .MARINE... Issued at 335 PM EDT Thu Jun 13 2024 Tonight...Invest 90L off the northeast FL coast will shift slowly northeast, with a weak trough axis across the northern waters. This will lead to varying winds out of the N/NW across the Volusia waters, around 5-10 knots, and out of the W/SW farther south up to 10-15 knots. Seas will range from 1-3 feet. Scattered showers and storms will continue to be possible, especially across the Treasure Coast waters into tonight. Friday-Monday...(Modified Previous Discussion) A weak front will shift into and remain in place across north central Florida through Friday and gradually fade into the weekend. Invest 90L is forecast to continue to move northeast off the eastern US coast. Winds will be rather variable around 5-10 knots on Friday, becoming E-SE on Saturday afternoon. Winds will become easterly and increase to 10-15 knots on Sunday as high pressure exits offshore of the eastern U.S. coast, and will remain onshore and increase into early next week with speeds up to 15-20 knots. Seas 2-3ft will increase up to 4 ft in the offshore waters on Monday. Scattered showers and scattered lightning storms will generally persist each day, especially across the Gulf Stream waters. && .AVIATION... (18Z TAFs) Issued at 109 PM EDT Thu Jun 13 2024 IMPACTS: -Heavy showers and storms affecting Treasure Coast early/mid afternoon today. -Sporadic showers and storms around Greater Orlando early this evening. -Potential MVFR CIGs for Space/Treasure Coast terminals tonight. A band of heavy rain and storms, with reduced visibilities to IFR or less and wind gusts to 35 KT, will affect FPR/SUA through 13/20Z. After that time, redevelopment of a few storms looks probable around the Orlando area between 13/22Z and 14/01Z. Overnight, a lull is expected with lowered CIGs especially MLB and southward. There is even a 20% chance of brief IFR CIGS, but confidence too low for TAF at this time. Surface trough overhead will make prevailing winds difficult through early evening: becoming NE around 10 KT for DAB with VRB/ESE winds at MCO. Treasure Coast will remain SW 5-15 KT. METARs are not currently reporting at DAB/FPR due to an outage. && .PRELIMINARY POINT TEMPS/POPS... DAB 74 90 74 92 / 40 60 20 40 MCO 75 92 75 91 / 60 60 30 60 MLB 73 89 74 89 / 60 60 40 60 VRB 73 89 72 89 / 60 70 50 70 LEE 76 94 76 95 / 60 60 30 50 SFB 74 92 75 94 / 50 60 30 50 ORL 76 92 75 93 / 50 60 30 60 FPR 72 89 72 89 / 60 70 50 70 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ DISCUSSION...Weitlich AVIATION...Heil