Area Forecast Discussion
Issued by NWS Melbourne, FL
Issued by NWS Melbourne, FL
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066 FXUS62 KMLB 291414 AFDMLB Area Forecast Discussion National Weather Service Melbourne FL 1014 AM EDT Sat Jun 29 2024 .UPDATE... Issued at 1015 AM EDT Sat Jun 29 2024 Early morning (10Z) Cape sounding shows precip water of 2.18" so quite a moist profile especially in the mid and upper levels. There is considerable mid and upper cloudiness assocd with this moisture and is supported by some upper vorticity that will push S/SW across the area during the day. The sounding also shows some relatively drier air just above the sfc which should is initially limiting the development of the diurnal cu field. But this drier air will mix out with time and a healthy cu field will develop during the afternoon. Weak pressure gradient producing light and variable winds and this will allow the east coast sea breeze to develop by early afternoon and push inland. Convective initiation is expected just inland from the coast along the sea breeze with the focus on the interior late in the day assocd with boundary collisions. The upper support should produce a high coverage of rain/storms over the interior with a few strong storms. Only change to the forecast for today was to lower rain chances through the morning over the Atlc and coastal areas. && .PREVIOUS DISCUSSION... Issued at 456 AM EDT Sat Jun 29 2024 Key Messages... -Higher coverage of showers and storms expected to continue today, especially inland, with locally heavy rainfall and a few stronger storms possible. -Scattered afternoon and evening showers and storms forecast Sunday into next week, with greatest coverage still focused across the interior. -Temperatures will remain near to slightly above normal this weekend through next week, with humid conditions leading to peak heat index values around 102-107 each day. Today-Tonight...Central Florida will be between a weak area of high pressure over the eastern Gulf of Mexico and high pressure over the Atlantic, with ridge axis extending across the area. This will lead to a light and variable wind flow across the region this morning, with the east coast sea breeze moving inland through the afternoon and switching winds onshore. A moist airmass remains in place, with PW values around 2.0-2.3 inches. While some mid to high cloud cover may persist into this morning, there should be sufficient daytime heating for scattered to numerous showers and storms to develop into the afternoon with the inland moving sea breeze boundaries. Greatest convective coverage will focus across the interior later into the afternoon where collisions between sea breeze and storm outflow boundaries are more likely. Have continued high rain chances today, with PoPs ranging from 60 percent along the coast to 70-80 percent across the interior. Steering winds will remain weak today, and out of the N/NW, which should lead to slower storm motion toward the S/SE. However, with the weaker steering winds, can`t rule out some variable storm motion along outflow boundaries that may shift some of this activity back toward the coast. Deep moisture in place will also increase the potential for locally heavy rainfall of around 2-4 inches with any persistent or slow moving storms. Gusty winds to 40- 50 mph and frequent lightning strikes may also occur with a few stronger storms. Convection and lingering areas of light to moderate debris cloud rainfall will gradually diminish into the evening, with rain chances mostly ending by midnight. However, a weak onshore flow may be able to transport a few showers or an isolated storm onshore overnight from the Cape southward. Highs will be closer to normal today, with values in the upper 80s to around 90 degrees along the coast and low 90s over the interior. However, the humid conditions will still lead to heat index values around 102-107 this afternoon, before storms and increasing cloud cover lead to some relief from the heat later in the afternoon. Overnight lows forecast to range from the low to mid 70s. Sunday-Friday...Atlantic subtropical ridge axis remains across the area from Sunday into early next week as a weak front moves into the southeast U.S. and stalls. Weaker and more variable low level winds continue across the area on Sunday, becoming more southerly into Monday and Tuesday. Low level winds then begin to veer more onshore into mid week as high pressure shifts offshore the eastern U.S. coast, and NHC forecasts show TC Beryl continuing to shift westward through the Caribbean Sea during this time. Model guidance then indicates continued west-northwest motion with this system through late week. Sea breeze will form each afternoon and move inland, with scattered showers and storms forecast to develop during the afternoon and evening hours along and inland of this boundary. However, greatest rain chances will remain across the interior where boundary collisions are favored to occur. PoPs on Sunday range from 40-50 percent along the coast to up to 60-70 percent across the interior, and then fall to 40-50 percent along the coast and 50-60 percent inland early to middle portion of next week. Some drier air building into the area later into the week, and strengthening onshore flow may then lead to a continued decrease in storm coverage, and have rain chances falling to 40-50 percent across the area into Thursday and Friday. Still can`t rule out a few stronger storms each day, with main threats being lightning strikes, strong gusty winds and locally heavy rainfall. Highs will still be near normal into Sunday, in the upper 80s to low 90s, and then in the low 90s early this week. Temps then continue to increase toward mid to late week as ridge aloft extends eastward across the area, with highs in the mid 90s forecast across portions of the interior, mainly near to northwest of I-4. Humid conditions will continue to produce peak heat index values during the afternoon around 102-107. Warm and muggy conditions continue during the overnight hours, with lows in the 70s. && .AVIATION... (12Z TAFs) Issued at 630 AM EDT Sat Jun 29 2024 IMPACTS: - Early morning fog reducing VIS to IFR/MVFR through 12Z at DAB. - Numerous afternoon and evening storms expected; Gusty winds to 35 KT, VIS restrictions to IFR & frequent lightning beneath storm cores. As suspected, light winds and saturation was enough to sprout a few patches of fog this morning, mostly up around DAB. VFR elsewhere, and VFR prevails at all sites through early afternoon. Thereafter, 60-80% storm chances for Greater Orlando terminals from 18Z-23Z, lessening to 40-60% for coastal terminals. At MCO, storms appear most likely in the 19Z-22Z timeframe. There is a ~ 20% chance for wind gusts to around 35 KT near the strongest storms. && .MARINE... Issued at 456 AM EDT Sat Jun 29 2024 Today-Tonight...Favorable boating conditions expected with light and somewhat variable winds this morning, becoming onshore this afternoon around 5-10 knots as east coast sea breeze forms and moves inland. Winds then veer southerly into tonight and remain relatively light. Seas 1-2 feet. Scattered to numerous showers and storms will develop into the afternoon, mainly inland, but still can`t rule out some of this activity shifting back toward the coast and offshore. Additional isolated to scattered showers and storms may develop over the waters, especially across the gulf stream waters. Sunday-Wednesday...Atlantic subtropical ridge axis will remain across the area through late weekend into early next week, maintaining favorable boating conditions. Light and variable winds expected again into Sunday morning, but then will become more southerly into early this week. Winds will become onshore each afternoon as the sea breeze moves inland, with speeds 5-10 knots on Sunday and increasing to around 10 knots Monday through Wednesday. Seas around 2 feet, may increase to 2-3 feet by mid week. Isolated to scattered showers and storms will continue to be possible over the coastal waters through the period. && .PRELIMINARY POINT TEMPS/POPS... DAB 90 75 90 75 / 70 40 50 20 MCO 92 76 91 74 / 80 40 60 20 MLB 89 75 89 75 / 60 30 40 20 VRB 89 75 89 74 / 60 30 50 20 LEE 92 77 92 76 / 80 40 60 30 SFB 92 75 92 75 / 80 40 60 20 ORL 92 76 92 76 / 80 40 60 20 FPR 90 75 89 74 / 60 30 50 20 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ UPDATE...Kelly AVIATION...Heil