Area Forecast Discussion
Issued by NWS Melbourne, FL
Issued by NWS Melbourne, FL
751 FXUS62 KMLB 291858 AFDMLB Area Forecast Discussion National Weather Service Melbourne FL 258 PM EDT Mon Apr 29 2024 ...New DISCUSSION, AVIATION, MARINE, FIRE WEATHER... .DISCUSSION... Issued at 255 PM EDT Mon Apr 29 2024 Tonight-Tuesday...From this morning`s 10z XMR sounding to recent ACARS data, the atmosphere depiction is very dry from 825-500mb. PW remain less than 1" in most places, with the exception of the Okeechobee and Treasure Coast region, as indicated by GOES- derived imagery. Farther south, across St. Lucie and Martin counties, a few low-topped showers are ongoing this afternoon. Onshore-moving showers such as these will continue into tonight along the Treasure Coast and eventually become more common by daybreak Tuesday. Some of this activity may begin to drift as far north as the Orlando or Cape Canaveral area by mid morning Tuesday. Temperatures in the morning start out mild in the 60s before climbing into the 80s Tuesday afternoon. Due to the east coast breeze, coastal locations are expected to stay in the low 80s with warmer values forecast from Orlando to points west. Isolated showers and even a couple of lightning storms are forecast to develop Tuesday afternoon and evening, aided by increased PW of 1.2-1.3"+ and an eventual east/west coast sea breeze collision over interior locations. Brief, moderate to heavy rains, gusty winds, and occasional lightning strikes will be the main features of any storms that do organize. Models indicate a slight push back of convection toward the coast Tuesday evening before activity eventually dissipates around midnight Wednesday. Localized rain amounts up to 0.50-0.75" are possible where repeated rains occur, notably from Lake Okeechobee to the Treasure Coast. Wednesday-Next Monday... Synoptic Overview...A weakness in the H5 flow across the Southeast will knock down heights just a bit through the middle of the week before ridging tends to build yet again by the weekend. At the surface, high pressure will slowly move out to sea, allowing the pressure gradient to relax over Florida through at least Saturday. As synoptic flow lessens, daily sea breeze collisions will begin to occur. Near-seasonable PW values will persist (0.8" to 1.3"), with much of the moisture focused in the lowest 300 mb. The ridging will promote very dry air in the mid-levels and broad subsidence. Thus, deep convection will be hard to achieve, but a few spots will have the potential to see some showers or even isolated storms. No fronts are expected. Sensible Weather & Impacts...Though we are still weeks away from the rainy season, the daily sea breeze collisions will offer up at least a low chance for mainly interior-focused showers and storms. Wednesday appears to be our "highest" coverage day of this period at around 20-30%, with at least some potential for this activity to work back toward the coast by evening. Thereafter, the coverage will fall to around 20% or less with many locales remaining dry, especially along the coastal corridor. As mentioned before, deep convection is not favored due to dry air above H7 and rather marginal instability. While this has the potential to dent the dry spell (or at least settle the dust) in a few lucky spots, we will also have to watch for any lightning that could spark fires in our abnormally dry locations. Outside of any lonely showers, the Sunshine State should live up to its name. High temps will remain warm each afternoon, within 5 degrees of normal, in the low/mid 80s along the coast to the upper 80s/low 90s elsewhere. Some relief will be found at night, with comfortable lows in the mid to upper 60s in most locations. Dew points should mainly hold in the 60s, yielding maximum heat index readings in the low/mid 90s over the far interior. && .AVIATION... (18Z TAFs) Issued at 255 PM EDT Mon Apr 29 2024 VFR persist with gusty conditions at coastal terminals. The east coast breeze will move inland after 21-22z and briefly increase east-southeasterly wind gusts from SFB/MCO westward thru 03z. Overnight, winds decrease most everywhere except from MLB southward, where a 10-12 kt breeze remains. Moisture increases tomorrow, leading to slightly higher coverage of -SHRA and isolated TS by the afternoon. Most activity will be focused from VRB southward thru 18z, before spreading north and west to MCO by the end of the TAF period. VCSH and -SHRA was included for now but future updates may require VCTS or even a TEMPO group if confidence in convection increases. && .MARINE... Issued at 255 PM EDT Mon Apr 29 2024 Tonight-Tuesday...Poor boating conditions are forecast tonight, mainly in the offshore waters due to winds 15-20 kt and seas up to 6 ft well offshore of Sebastian Inlet. SE winds slacken toward daybreak Tuesday, and seas gradually decrease thru the day. The sea breeze along the coast is forecast to begin moving inland by early afternoon, increasing winds a bit over the nearshore waters. Seas 2-4 ft nearshore, up to 5 ft offshore. In addition, isolated showers and lightning storms are possible thru the day. Wednesday-Friday...A daily sea breeze circulation will increase winds along the coast to E 10-15 KT each afternoon. Otherwise, prevailing winds will remain SE from 5-12 KT with some potential to turn offshore near the coast in the overnight hours. Seas will be rather benign, ranging from 2-4 FT. A few offshore-moving showers or isolated storms are possible (~20% chance) on Wednesday evening. Otherwise, only isolated (20-30%) showers and storms, mainly in the Gulf Stream, favored in the morning hours. && .FIRE WEATHER... Issued at 255 PM EDT Mon Apr 29 2024 Tuesday...Minimum relative humidity values recover on Tuesday as moisture increases over the area. Winds will remain lighter inland, 10 mph or less, while areas east of Deland/Orlando, nearer to the coast, will be breezy around 10-15 mph with gusts reaching 20 mph. Isolated lightning storms are possible in the afternoon and early evening, so a localized fire start from occasional lightning strikes cannot be ruled out. Combined with dry antecedent conditions, fire sensitive conditions are expected to continue. Wednesday-Friday...RH minima will continue to fall over the interior to around 38-45% each afternoon, along with E winds of 5-12 MPH. Winds will become light and variable overnight; in the vicinity of fires, patchy fog may mix with smoke to reduce visibilities as RH recoveries reach 90% +. Wetting rain chances remain around 20% Wednesday before falling to less than 15% Thu/Fri. Isolated lightning starts are possible if any storms develop. && .PRELIMINARY POINT TEMPS/POPS... DAB 65 83 66 86 / 10 20 10 10 MCO 65 87 68 90 / 10 30 10 20 MLB 68 81 68 85 / 10 20 20 20 VRB 66 82 65 86 / 20 30 30 20 LEE 67 87 68 88 / 10 30 10 20 SFB 66 86 68 89 / 10 30 10 20 ORL 66 87 69 89 / 10 30 10 20 FPR 66 82 65 86 / 20 30 30 20 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ SHORT TERM...Schaper LONG TERM...Heil AVIATION...Schaper DECISION SUPPORT...Weitlich