textproduct: Melbourne

KEY MESSAGES

Issued at 300 AM EDT Thu Aug 13 2026

- Heat Advisory is in effect for all of east central Florida from 10am to 8pm for heat index values up to 108F-112F degrees; Remember to practice heat safety!

- A major heat wave is expected for the next week with hot and humid conditions. Maximum heat index values will reach near Heat Advisory criteria (108F+) each day through the weekend; Additional Heat Advisories are likely for at least portions of east central Florida.

- Below normal rain chances continue into early next week. Drier air aloft due to the Saharan Air Layer will support strong and gusty winds in any lightning storms each day.

DISCUSSION

Issued at 300 AM EDT Thu Aug 13 2026

Currently-Tonight... KMLB radar imagery shows dry weather over east central Florida. GOES-19 and local observations indicate mostly clear to partly cloudy skies. Temperatures are currently in the mid 70s to around 80 degrees with dew points in the low to mid 70s. Analysis charts show a mid/upper level ridge over the Gulf and eastern CONUS. High pressure (1018mb) at the surface over the eastern Gulf. Additionally, the 15Z and 00Z XMR skew-t soundings from yesterday still showed quite a bit of dry air in the mid to upper levels due to a Saharan Dust layer.

Not much change is expected today in terms of the airmass with drier air still expected in the mid to upper levels due to Saharan dust as high pressure builds over the Gulf and southern US. Isolated to scattered showers (30-50% chance) and lightning storms are forecast to develop in the afternoon and evening today as collisions occur between light west-northwest flow, the east coast sea breeze, and outflow from previous storms. Rain chances diminish by around 8PM. Light west- northwest winds will back onshore into the afternoon and evening as the east coast sea breeze pushes inland, mainly along and south of I-4. Hi-res guidance shows MLCAPE up to 1,000-3,600 J/kg, 0-6km shear up to 10-25kts, PWATs up to 1.80-2.20", and mid level lapse rates up to 6.0-6.7 C/km today. The aforementioned weather parameters are favorable for isolated strong storms capable of frequent lightning, wind gusts up to 30-50mph, and heavy rainfall (up to 1-3"). Guidance shows 500mb heights at the 90th percentile (594dm) and potentially the maximum percentile (597dm) by this evening over the southern US and the state of Florida. Thus, a hot and muggy day is expected again with maximum temperatures in the mid to upper 90s. Additionally, a Heat Advisory has been issued for all of east central Florida from 10AM to 8PM for heat index values up to 108-112F degrees. Remember to take frequent breaks from the heat, drink plenty of fluids, wear light colored clothing, and shift outdoor work away from the hottest parts of the day between the hours of 10am to 4pm. Above normal (2-4+ degrees) lows in mid 70s to near 80F degrees are forecast overnight.

Friday-Sunday... A persistent forecast is expected with drier air in the mid to upper levels expected to keep rain chances below normal through the weekend. Model guidance is in good agreement that the mid/upper level ridge will build over the Gulf and eastern CONUS through Sunday before shifting west-southwest Sunday evening. Guidance shows 500mb heights reaching the Expect maximum percentile for this time of year at 598dm. Expect isolated to scattered showers (20-40% chance) and lightning storms to develop in the afternoon and evening as collisions occur between sea breezes and outflow from previous showers/lightning storms before rain chances diminish by around 8PM on Friday. Below normal rain chances (20-50%) are expected to continue on Saturday with the greatest chances across the Treasure Coast to Okeechobee county (50%). Light and variable winds will increase into the afternoon and evening at 5-10mph near the coast on Sunday. Mostly dry conditions are expected on Sunday with a low chance (20-30%) for isolated to widely scattered showers and lightning storms forecast along and north of Lake Kissimmee to Cocoa. Afternoon highs in the mid to upper 90s are forecast. Additional heat advisories are likely through at least Saturday with heat index values up to 108-112F degrees forecast. A widespread Moderate to Major HeatRisk is forecast with a widespread Extreme HeatRisk mainly north of the Treasure Coast. A Major and Extreme HeatRisk affect anyone without adequate cooling and hydration.

Monday-Wednesday... Much of the same is forecast through at least the early part of the week with high pressure still in place over the Gulf and southern US. Ensembles, LREF-clusters, and deterministic models are in fairly good agreement that the mid/upper level ridge will shift west-southwest over the southern US as a mid/upper trough deepens over the northeastern US. At the surface, a frontal boundary is forecast to sag over the eastern CONUS and southern US Tuesday into Wednesday. Below normal rain chances are forecast to continue, as well as hot and muggy conditions. A widespread Major HeatRisk is likely for much of east central Florida each day. Additionally, the probabilities for an Extreme HeatRisk are up to 30-70% over areas mainly north of the Treasure Coast each day.

MARINE

Issued at 300 AM EDT Thu Aug 13 2026

Currently-Tonight... Favorable boating conditions are expected outside of any showers and lightning storms. There is a low chance (20-30%) for isolated generally offshore moving showers and lightning storms. A strong storm capable of wind gusts at or above 34kts cannot be ruled out. West winds at 5-10mph are expected to turn southerly into the afternoon and evening, as well as onshore along the coast with the east coast sea breeze.

Friday-Monday... Favorable boating conditions outside of showers and lightning storms are expected to continue through the forecast period with high pressure over east central Florida. Below normal rain chances are forecast to continue with mostly dry conditions each day. However, isolated offshore moving showers and lightning storms cannot be ruled out on Friday and Saturday. South- southwest winds at around 5-10mph are expected to back south- southeast each afternoon and evening Friday to Sunday, as well as onshore near the coast with the east coast sea breeze. West winds are forecast to turn east Monday afternoon. Seas up to 1-2ft are forecast with up to 3 ft forecast over the far offshore Volusia to Brevard county waters on Monday.

AVIATION

(06Z TAFs) Issued at 125 AM EDT Thu Aug 13 2026

VFR conditions and light SW winds persist this morning across the terminals. Winds pick up out of the NW after 14Z, becoming E along the coast after 18Z as the east coast sea breeze develops and moves inland. Increasing potential for VCTS along the sea breeze, with the best chances focused at MCO, ISM, and SFB after 18Z. Too early to include PROB30/TEMPO groups, but will continue to monitor model trends. Activity is anticipated to diminish after 23Z along the coast and 01Z across the interior, with a return of light SW winds overnight.

PRELIMINARY POINT TEMPS/POPS

DAB 96 77 96 77 / 40 10 40 0 MCO 97 77 97 77 / 40 20 40 20 MLB 95 78 94 78 / 40 10 30 0 VRB 94 76 94 77 / 30 10 20 0 LEE 96 78 97 78 / 30 20 40 20 SFB 96 77 96 77 / 40 10 40 10 ORL 96 78 96 77 / 40 10 40 20 FPR 94 76 94 77 / 30 10 20 0

MLB WATCHES/WARNINGS/ADVISORIES

FL...Heat Advisory from 10 AM this morning to 8 PM EDT this evening for FLZ041-044>046-053-058-141-144-154-159-164-247-254-259- 264-347-447-547-647-747.

AM...None.