192  
FXUS62 KMLB 212332  
AFDMLB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MELBOURNE FL  
732 PM EDT TUE JUL 21 2026  
   
..NEW AVIATION  
 
   
KEY MESSAGES  
 
ISSUED AT 233 PM EDT TUE JUL 21 2026  
 
- DRIER AIR WILL LEAD TO LOWER THAN NORMAL SHOWER AND STORM  
CHANCES THROUGH THROUGH AT LEAST THURSDAY. INCREASING MOISTURE  
INTO LATE WEEK AND THROUGH THE WEEKEND WILL THEN ALLOW RAIN  
CHANCES TO RETURN TO NEAR NORMAL VALUES.  
 
- NEAR TO ABOVE-NORMAL AFTERNOON TEMPERATURES WILL PERSIST THROUGH  
THE PERIOD WITH PEAK HEAT INDICES EXCEEDING 100F EACH DAY.  
PRACTICING HEAT SAFETY WILL BE KEY TO AVOID HEAT-RELATED  
ILLNESS!  
 
 
   
DISCUSSION  
 
ISSUED AT 233 PM EDT TUE JUL 21 2026  
 
CURRENTLY-TONIGHT...SOME DRIER AIR IS NUDGING ITS WAY IN FROM THE  
SOUTHEAST, WITH GOES-19 TPW IMAGERY SHOWING GREATER MOISTURE (PW 1.6-  
1.7") FOCUSED INLAND. THIS SHOULD KEEP A MAJORITY OF ISOLATED TO  
SCATTERED SHOWERS AND STORMS (POPS 20-40%) THAT FORM THROUGH LATE  
AFTERNOON AND TOWARD SUNSET ACROSS THE INTERIOR, ESPECIALLY ALONG  
AND WEST OF THE I-4 CORRIDOR. A PREVAILING SOUTHERLY FLOW EAST OF TS  
BERTHA THATS CENTERED SOUTH OF THE WESTERN FL PANHANDLE, WILL  
TRANSPORT THIS ACTIVITY NORTHWARD THROUGH THIS EVENING, WITH THIS  
ACTIVITY DIMINISHING BY MIDNIGHT. DCAPE VALUES BETWEEN 1000-1500  
J/KG AND AN THE ELEVATED SOUTHERLY STEERING FLOW (15-20 KTS) MAY  
STILL ALLOW FOR A FEW STRONGER STORMS TO DEVELOP, WITH THE MAIN  
THREATS BEING STRONG WIND GUSTS UP TO 40-50 MPH AND FREQUENT  
LIGHTNING. REPEATED ROUNDS OF HEAVIER SHOWERS AND STORMS MAY ALSO  
LEAD TO LOCALIZED HEAVY RAINFALL OF 1-3" IN SPOTS.  
 
MOSTLY DRY CONDITIONS THEN FORECAST OVERNIGHT, WITH ONLY A SLIGHT  
(20%) CHANCE FOR ONSHORE MOVING SHOWERS ALONG THE SOUTHERN TREASURE  
COAST LATE TONIGHT. REMAINING WARM TONIGHT, WITH LOWS FOR MOST  
LOCATIONS IN THE MID TO UPPER 70S.  
 
WEDNESDAY-THURSDAY...TS BERTHA WILL CONTINUE A GRADUAL WESTWARD  
MOTION THROUGH MIDWEEK, EITHER ALONG OR JUST SOUTH OF THE NORTHERN  
GULF COAST. THE SFC ATLANTIC RIDGE AT THE SAME TIME GRADUALLY  
EXTENDS ACROSS CENTRAL FL, WITH RIDGE AXIS LIFTING NORTHWARD. THIS  
WILL ALLOW WINDS TO WEAKEN AS THEY GRADUALLY BECOME MORE ONSHORE,  
BACKING TO THE S/SE TOMORROW AND E/SE INTO THURSDAY. SHOWER AND  
STORM COVERAGE REMAINS BELOW NORMAL OVERALL THROUGH MIDWEEK, AS  
DRIER AIR EAST OF BERTHA LINGERS. GREATEST CHANCE FOR AFTERNOON AND  
EVENING SHOWERS AND STORMS WEDNESDAY (POPS UP TO 30-40%) WILL BE  
ACROSS OKEECHOBEE COUNTY AND TREASURE COAST REGION DURING THE  
AFTERNOON, AND THEN FOCUSED WEST OF ORLANDO WITH THE SEA BREEZE  
COLLISION NEAR TO AFTER SUNSET. THE MORE DOMINANT ONSHORE FLOW ON  
THURSDAY SHOULD LOWER RAIN CHANCES EVEN MORE, WITH ONLY A SLIGHT  
(20%) CHANCE OF SHOWERS AND STORMS CURRENTLY FORECAST ACROSS THE  
INTERIOR THROUGH THE AFTERNOON/EARLY EVENING. THE DRIER AIR ALOFT  
WILL STILL KEEP A POTENTIAL FOR ISOLATED STRONG STORMS, PRODUCING  
STRONG WIND GUSTS AND FREQUENT LIGHTNING.  
 
HIGHS WILL CONTINUE TO BE NEAR TO ABOVE NORMAL, IN THE LOW 90S ALONG  
THE COAST AND MORE WIDESPREAD MID 90S ACROSS THE INTERIOR. THE DRIER  
AIR ALOFT SHOULD LOWER DEWPOINTS AS MIXING INCREASES INTO THE  
AFTERNOON. THEREFORE, PEAK HEAT INDEX VALUES ARE FORECAST TO REMAIN  
BELOW HEAT ADVISORY CRITERIA, BUT SHOULD STILL RANGE FROM 100-107F.  
THOSE SPENDING EXTENDED PERIODS OF TIME OUTDOORS WILL NEED TO REMAIN  
ADEQUATELY HYDRATED AND TAKE FREQUENT BREAKS IN THE SHADE OR AN AIR-  
CONDITIONED BUILDING TO AVOID HEAT-RELATED ILLNESS. WARM AND HUMID  
CONDITIONS WILL PREVAIL OVERNIGHT, WITH LOWS CONTINUING IN THE MID  
TO UPPER 70S FOR MUCH OF THE AREA.  
 
FRIDAY-MONDAY...(PREVIOUS DISCUSSION) BROAD MID-LEVEL RIDGING WILL  
REMAIN IN PLACE ACROSS THE SOUTHERN US LATE THIS WEEK, WITH A TROUGH  
ACROSS THE EASTERN US GRADUALLY DIGGING SOUTHWARD TOWARDS FLORIDA  
INTO THIS WEEKEND AND EARLY NEXT WEEK. AT THE SURFACE, BROAD HIGH  
PRESSURE IS FORECAST TO REMAIN SITUATED ACROSS THE LOCAL ATLANTIC  
WATERS ON FRIDAY, WITH THE HIGH GRADUALLY PUSHING SOUTHWARD THIS  
WEEKEND AS A LOW MOVES OFFSHORE THE CAROLINAS AND DRAGS A FRONTAL  
BOUNDARY SOUTHWARD ACROSS THE SOUTHEASTERN US. THE BOUNDARY WILL  
STALL ACROSS NORTH FLORIDA ON SUNDAY, CONTINUING TO DRIFT SOUTHWARD  
TOWARDS THE PENINSULA INTO EARLY NEXT WEEK AS IT WEAKENS. LOCALLY,  
LINGERING DRY AIR ACROSS THE AREA ON FRIDAY WILL KEEP RAIN CHANCES A  
BIT LIMITED ACROSS THE NORTH, WITH INCREASING MOISTURE ACROSS THE  
TREASURE COAST AND NEAR LAKE OKEECHOBEE CAUSING A RETURN OF NEAR TO  
ABOVE NORMAL RAIN CHANCES. BY THIS WEEKEND, A MOIST AIR MASS WILL  
OVERSPREAD THE FLORIDA PENINSULA AND THE TYPICAL DIURNAL SUMMERTIME  
PATTERN IS FORECAST, WITH CONVECTIVE ACTIVITY PRIMARILY BEING DRIVEN  
BY THE SEA BREEZES AND THEIR INTERACTIONS. A RETURN OF WESTERLY FLOW  
WILL ALSO FAVOR HIGHER COVERAGE ACROSS THE EASTERN PORTIONS OF THE  
PENINSULA NEAR THE COAST. BY MONDAY, THE MOISTURE FROM THE DECAYING  
BOUNDARY WILL ARRIVE ACROSS EAST CENTRAL FLORIDA, WITH CONTINUED  
NEAR-NORMAL RAIN CHANCES FORECAST THROUGH THE AFTERNOON HOURS  
AREAWIDE. OVERALL, SHOWERS AND STORMS ARE FORECAST TO DIMINISH EACH  
EVENING THROUGH THE OVERNIGHT HOURS, WITH LINGERING ACTIVITY  
POSSIBLE ACROSS THE LOCAL ATLANTIC WATERS.  
 
ABOVE NORMAL TEMPERATURES ARE FORECAST TO CONTINUE ACROSS EAST  
CENTRAL FLORIDA THROUGH SUNDAY, WITH SOME INDICATION THAT THE  
INCREASING MOISTURE AND CLOUD COVERAGE WILL HELP KEEP TEMPERATURES  
CLOSER TO NORMAL ON MONDAY AFTERNOON. PEAK HEAT INDICES WILL  
CONTINUE TO EXCEED 100F AREAWIDE, WITH SOME LOCATIONS POTENTIALLY  
NEARING HEAT ADVISORY CRITERIA. CONFIDENCE IN THIS REMAINS LOW  
THOUGH, SO WILL CONTINUE TO MONITOR. LOWS GENERALLY IN THE 70S.  
 
 
   
MARINE  
 
ISSUED AT 233 PM EDT TUE JUL 21 2026  
 
TONIGHT-WEDNESDAY...TS BERTHA WILL CONTINUE A SLOW WESTWARD MOTION  
NEAR TO JUST SOUTH OF THE NORTHERN GULF COAST THROUGH MIDWEEK. SMALL  
CRAFT WILL NEED TO CONTINUE TO EXERCISE CAUTION ACROSS THE VOLUSIA  
COUNTY WATERS INTO TONIGHT, AS S/SE WINDS AROUND 15-20 KNOTS  
PERSIST. ELSEWHERE, WINDS WILL MOSTLY RANGE FROM 10-15 KNOTS THROUGH  
TONIGHT. WINDS THEN REMAIN OUT OF THE S/SE THROUGH WEDNESDAY AROUND  
10-15 KNOTS FOR MUCH OF THE WATERS, BUT MAY ONCE AGAIN INCREASE TO  
15-20 KNOTS ACROSS THE NEARSHORE VOLUSIA COUNTY WATERS INTO THE  
AFTERNOON. SEAS WILL RANGE FROM 2-4 FEET. IT WILL BE MOSTLY DRY, BUT  
ISOLATED SHOWERS AND STORMS WILL STILL DEVELOP, MAINLY OVER THE GULF  
STREAM WATERS.  
 
THURSDAY-SUNDAY...THE PRESSURE GRADIENT IS FORECAST TO WEAKEN ACROSS  
THE LOCAL WATERS AS ATLANTIC HIGH PRESSURE EXTENDS BACK ACROSS THE  
REGION THROUGH LATE WEEK AND THEN SHIFTS SOUTHWARD INTO THE WEEKEND.  
PREDOMINANT ONSHORE WINDS INTO LATE WEEK, ARE FORECAST TO VEER MORE  
OFFSHORE INTO THE WEEKEND, BUT WINDS WILL STILL BECOME S/SE EACH  
AFTERNOON/EVENING AS THE EAST COAST SEA BREEZE FORMS. WIND SPEEDS  
GENERALLY REMAIN BELOW 15 KNOTS, WITH SEAS 1-3 FEET. DRIER AIR WILL  
CONTINUE MOSTLY DRY CONDITIONS INTO THURSDAY, AND THEN EXPECT A  
GRADUAL RISE IN RAIN AND STORM CHANCES FROM FRIDAY AND INTO THE  
WEEKEND AS MOISTURE INCREASES.  
 
 
   
AVIATION  
 
(00Z TAFS)  
ISSUED AT 731 PM EDT TUE JUL 21 2026  
 
VFR CONDITIONS ARE FORECAST OUTSIDE OF SHOWERS/STORMS. VCTS IS  
FORECAST THROUGH 03Z AT THE TAFS ALONG & NEAR I-4 WITH TEMPO TSRA  
BETWEEN 00Z/01Z. SSE WINDS AT 10-14KTS WITH GUSTS TO 15-20KTS ARE  
FORECAST TO GRADUALLY WEAKEN, ESPECIALLY AFTER 03Z BEFORE INCREASING  
AFTER 13Z WED AT 8-10KTS. VCSH IS FORECAST AFTER 21Z/22Z ALONG &  
N OF I-4 WED; VCTS MAY BE ADDED LATER IF CONFIDENCE INCREASES.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
DAB 76 93 76 92 / 20 10 0 10  
MCO 76 96 77 96 / 30 20 20 20  
MLB 77 91 77 90 / 10 20 0 10  
VRB 75 91 75 91 / 10 20 10 10  
LEE 77 95 77 95 / 20 10 30 20  
SFB 76 95 77 95 / 30 20 10 20  
ORL 77 95 77 95 / 30 20 20 20  
FPR 75 91 75 91 / 10 30 10 10  
 
 
   
MLB WATCHES/WARNINGS/ADVISORIES  
 
FL...NONE.  
AM...NONE.  
 
 
 
 
DISCUSSION...WEITLICH  
AVIATION...FEHLING  
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