070
FXUS62 KKEY 100804
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
404 AM EDT THU SEP 10 2026
..NEW DISCUSSION, MARINE, AVIATION
KEY MESSAGES
- MOISTURE WILL LINGER ACROSS THE REGION THROUGH THE END OF THE
WEEK, SUPPORTING RAIN AND THUNDERSTORM CHANCES.
- THE PRIMARY THREAT FOR ANY STRONGER THUNDERSTORMS WILL BE
DANGEROUS LIGHTNING STRIKES. WHEN THUNDER ROARS, GO INDOORS. IF
ON A BOAT, STAY LOW, OR GO BELOW.
- HEAT INDEX VALUES WILL RANGE FROM 100-108 DEGREES DAILY WITH
LITTLE RELIEF FROM THE MUGGY CONDITIONS OVERNIGHT. KNOW THE
SIGNS OF HEAT STRESS, TAKE FREQUENT BREAKS, AND STAY HYDRATED.
DISCUSSION
ISSUED AT 103 AM EDT THU SEP 10 2026
ELONGATED SURFACE THROUGH MID LEVEL RIDGING IS ALIGNED OVER THE
SOUTHEASTERN UNITED STATES. AT THE SURFACE, THIS HAS ALLOWED
FOR MOSTLY GENTLE EASTERLY BREEZES TO BUILD IN ACROSS THE KEYS.
DEEP LAYERED MOISTURE REMAINS QUITE HIGH WITH LAST EVENINGS
SOUNDING INDICATED THE PRECIPITABLE WATER WAS AROUND THE 75TH
PERCENTILE AT 2 INCHES WITH SEASONABLE INSTABILITY. THE
ENVIRONMENT HAS BEEN SUPPORTIVE OF SCATTERED SHOWERS WITH EMBEDDED
THUNDERSTORMS. THE LATEST ROUND OF ACTIVITY IS IN THE PROCESS OF
VISITING MUCH OF THE FLORIDA KEYS. TEMPERATURES ARE NEAR NORMAL
WITH DEW POINTS MUGGY IN THE UPPER 70S.
RAIN CHANCES ARE SET TO REMAIN ABOVE NORMAL IN THE NEAR TERM. A
SWATH OF ENHANCED MOISTURE IS EXPECTED TO PUSH THROUGH THE KEYS,
AND GUIDANCE HINTS AT SOME CYCLONIC CURVATURE THROUGH THE LOWER
LEVELS. THE HRRR IS FAIRLY ENTHUSIASTIC ABOUT SHOWER AND
THUNDERSTORM COVERAGE TODAY AND APPEARS TO BE AT LEAST PARTIALLY
DRIVEN BY QUITE A BIT OF CONVERGENCE NEAR THE CENTRAL BAHAMAS. AS
A RESULT, HAVE NUDGED POPS UP TO LIKELY FOR TODAY. THE RIDGE WILL
REMAIN THE DOMINANT SYNOPTIC PLAYER AND SURFACE WINDS WILL REMAIN
MOSTLY GENTLE EAST TO SOUTHEASTERLY THROUGH MUCH OF THE DAY, BUT
IS EXPECTED TO STRENGTHEN MODESTLY THIS EVENING. EXPECT NEAR TO
SLIGHTLY ABOVE NORMAL TEMPERATURES WITH DEW POINTS REMAINING
STICKY IN THE UPPER 70S.
RAIN CHANCES SHOULD FALL CONSIDERABLY TO SLIGHT OR LOW CHANCE
TONIGHT AS A BAND OF DRIER AIR WITH WEAK 850 MB INHIBITION IS
EXPECTED TO PUSH THROUGH THE AREA. THIS LULL IN COVERAGE IS
EXPECTED TO BE FAIRLY SHORT LIVED AS LOWER LEVEL MOISTURE
QUICKLY CLIMBS AGAIN EARLY FRIDAY, ALONG WITH CONTINUED WEAK
CYCLONIC CURVATURE TUCKED IN UNDER THE RIDGE. AS A RESULT, EXPECT
A RETURN TO SLIGHTLY ABOVE NORMAL RAIN CHANCES. BREEZES WILL
GRADUALLY SHIFT SOUTHEASTERLY AND SLACKEN SLIGHTLY AS THE SURFACE
RIDGE IS EXPECTED TO RETREAT FURTHER INTO THE ATLANTIC WHILE THE
AXIS SHIFTS DOWN ACROSS THE PENINSULA.
THROUGH EARLY NEXT WEEK, THE LOWER LEVEL RIDGE WILL BE REINFORCED
BY A CONTINENTAL HIGH MARCHING EASTWARD BEHIND A MID LATITUDE
TROUGH. THE RIDGE IS EXPECTED TO SETUP QUITE A BIT FURTHER NORTH
ACROSS THE SOUTHERN STATES. SHOULD THIS OCCUR, THE RIDGE'S
TRADEWIND BELT WILL LIFT INTO OUR AREA AND EASTERLY BREEZES
SHOULD FRESHEN MODESTLY. UNIDIRECTIONAL EASTERLY FLOW ALONG THE
SOUTHERN PERIPHERY OF THE DEEP LAYERED ANTICYCLONE WILL HOPEFULLY
ALLOW RAIN CHANCES TO SLIP CLOSER TO NORMAL.
MARINE
ISSUED AT 103 AM EDT THU SEP 10 2026
ATLANTIC RIDGING STRETCHING WESTWARD THROUGH THE SOUTHEAST AND
FLORIDA WILL MAINTAIN GENTLE TO MODERATE MOSTLY EASTERLY BREEZES
ON KEYS WATERS THROUGH THE NEXT COUPLE OF DAYS. BREEZES ARE
EXPECTED TO TIP SUBTLY FURTHER SOUTHEASTERLY AND WEAKEN HEADING
INTO THIS WEEKEND AS THE BODY OF THE RIDGE RETREATS INTO THE
ATLANTIC. SHOWER AND THUNDERSTORM CHANCES WILL BE ELEVATED IN THE
SHORT TERM. THROUGH THE EARLY PORTION OF NEXT WEEK THE RIDGE WILL
BE REINFORCED BY A NEW HIGH CELL FOLLOWING A MID LATITUDE TROUGH
EASTWARD ACROSS THE EASTERN UNITED STATES. THIS WILL MAINLY HELP
TO KEEP BREEZES GENTLE TO MODERATE OUT OF THE EAST.
AVIATION
(06Z TAFS)
ISSUED AT 103 AM EDT THU SEP 10 2026
VFR CONDITIONS WILL PREVAIL AT THE ISLAND TERMINALS TODAY. WITH
THAT SAID, A WETTER THAN NORMAL PERIOD IS EXPECTED TODAY AND THERE
IS A BETTER THAN EVEN CHANCE FOR BOUTS OF SHOWERS AND POTENTIAL
THUNDERSTORMS AT THE TERMINALS. SURFACE WINDS WILL BE LIGHT TO
GENTLE OUT OF THE EAST TO SOUTHEAST.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 92 82 92 82 / 70 30 50 30
MARATHON 90 84 90 83 / 60 30 40 50
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...11
AVIATION/NOWCASTS....11
DATA ACQUISITION.....DM
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