381
FXUS62 KKEY 171905
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
305 PM EDT SUN AUG 17 2025
..NEW AVIATION
AVIATION
(18Z TAFS)
ISSUED AT 305 PM EDT SUN AUG 17 2025
VFR CONDITIONS WILL PREVAIL AT BOTH EYW AND MTH FOR THE REST OF
TODAY AND INTO TONIGHT. CLOUD LINE FORMATION HAS BEEN LIMITED DUE
TO DRIER AIR SETTLING IN ALOFT AND WHILE A STRAY SHOWER OR TWO IS
STILL POSSIBLE NEAR EITHER TERMINAL, VCSH IS NOT MENTIONED AT THIS
TIME. NEAR SURFACE WINDS WILL CONTINUE TO BE LIGHT AND BROADLY OUT
OF THE SOUTHEAST, BECOMING EAST TO SOUTHEAST LATER TONIGHT.
PREVIOUS DISCUSSION
ISSUED AT 1111 AM EDT SUN AUG 17 2025
IT HAS BEEN A FAIRLY NORMAL START TO THIS MID AUGUST DAY ACROSS
THE FLORIDA KEYS. KBYX RADAR HAS RECORDED WIDELY SCATTERED BUT
SHALLOW NOCTURNAL SHOWERS BUBBLING ALONG BOUNDARIES STRETCHED
ACROSS THE DEEP GULF WATERS AND STRAITS OF FLORIDA. A FEW OF THESE
WERE ABLE TO BRIEFLY CROSS OVER THE ISLAND CHAIN. MRMS 6 HOUR QPE
NOTES THAT NOTHING MORE THAN HALF AN INCH WAS ESTIMATED TO FALL OVER
LAND. GOES-19 VISIBILE IMAGERY CURRENTLY DEPICTS A HANDFUL OF
SHOWERS STILL IN THE GULF AND STRAITS OFF THE MIDDLE AND LOWER
KEYS, BUT A NOTABLE GAP IS OBSERVED IN THE EASTERN STRAITS AND
SOUTHERNMOST EDGES OF OUR WATERS. ANOTHER INTERESTING DETAIL IS A
CLOUD LINE FORMING JUST WEST OF THE UPPER KEYS WITH LESS CLOUD
COVER OBSERVED OVER THE LOWER AND MIDDLE KEYS THAN YESTERDAY
AROUND THIS TIME. THIS HAS ALLOWED TEMPERATURES TO REACH
RELATIVELY THE SAME POINT AS YESTERDAY IF NOT A TOUCH HIGHER THAN
THE UPPER 80S TO NEAR 90 RANGE. LIGHT EAST TO SOUTHEAST BREEZES
PREVAIL ALONG THE REEF.
TODAY HAS THE POTENTIAL TO DEVELOP ANOTHER ROUND OF CLOUD LINES
ACROSS THE ISLAND CHAIN. THERE IS ALREADY ONE ONGOING ALONG THE
UPPER KEYS, BUT ONLY A FEW SHOWERS ARE STARTING TO DEVELOP IN IT.
THIS MORNING'S KKEY SOUNDING LOOKS TO MOSTLY GIVE A GREEN LIGHT
FOR THIS FORECAST. THE POCKET OF LOW TO MID LEVEL DRY AIR IS
MOSTLY MIXED OUT, THOUGH A SMALL INVERSION STILL EXISTS AROUND
700 MB WHERE IT STARTED. OTHERWISE, THERE IS PLENTY OF INSTABILITY
ALONG WITH LIGHT LOW LEVELING WINDS AND DECENT AMOUNT OF LOW
LEVEL MOISTURE. WHILE THIS PROFILE LOOKS GOOD ON PAPER, THERE ARE
A FEW FACTORS THAT MAY HINDER CONVECTIVE DEVELOPMENT. CIMMS MIMIC
LAYER TPW NOTES A MASS OF DRIER AIR ALREADY PRESENT IN THE
EASTERN STRAITS OF FLORIDA WHERE CONVECTIVE DEVELOPMENT HAS BEEN
MOSTLY CEASED. MEANWHILE, A WEAKLY ANTICYCLONIC FLOW OBSERVED IN
THE STRAITS VIA GOES-19 ALSO LOOKS TO BE PULLING IN SOME CUBAN
SHADOW FROM THE SOUTH WITH DRIER AIR APPROACHING THE ISLAND CHAIN
FROM NOW TWO DIRECTIONS. IT SEEMS LIKE IT WILL BE SOMEWHAT OF A
RACE BETWEEN THE CLOUD LINES FORMING AND DRY AIR INTRUDING, BUT AS
SUCH WE WILL HOLD ONTO CHANCE POPS EXPECTING AT LEAST SOME CLOUD
LINE DEVELOPMENT THIS AFTERNOON ALONG WITH POSSIBLY MORE NOCTURNAL
CONVECTION TONIGHT.
FORECAST
ISSUED AT 408 AM EDT SUN AUG 17 2025
LOOKING AHEAD, THE WESTERN ATLANTIC SUBTROPICAL RIDGE WILL REMAIN
FIRMLY IN PLACE THROUGH AT LEAST THE EARLY PARTS OF THIS WEEK,
PROVIDING LIGHT TO GENTLE BREEZES THAT WILL BE OCCASIONALLY
VARIABLE. WITH MINIMAL SUPPORT ALOFT, CONVECTION ACROSS THE KEYS
WILL REMAIN LIMITED OR ISOLATED IN COVERAGE WHEN IT OCCURS.
FARTHER EAST, HURRICANE ERIN WILL TRACK NORTHWARD OVER THE OPEN
ATLANTIC AND REMAIN WELL OUTSIDE OUR FORECAST AREA. EVEN SO,
MODEST MOISTURE FROM THE SYSTEMS WESTERN SIDE COULD SLIGHTLY
ELEVATE RAIN CHANCES AROUND MIDWEEK, THOUGH NO DIRECT IMPACTS ARE
EXPECTED. FOR NOW, IT SEEMS DRY CONTINENTAL AIR FROM THE
NORTHWESTERLY WINDS WILL KEEP SHOWERS AT BAY. STAY TUNED FOR ANY
UPDATES.
MARINE
ISSUED AT 305 PM EDT SUN AUG 17 2025
NO WATCHES, WARNINGS, OR ADVISORIES ARE CURRENTLY IN EFFECT FOR
THE COASTAL WATERS OF THE FLORIDA KEYS. FROM SYNOPSIS, A BROAD
RIDGE STRETCHING FROM THE NORTH ATLANTIC WESTWARD ACROSS THE
FLORIDA PENINSULA WILL RESULT IN LIGHT TO GENTLE EASTERLY BREEZES
ACROSS THE KEYS COASTAL WATERS THROUGH EARLY THIS WEEK. AS
HURRICANE ERIN APPROACHES AND PASSES BY THE BAHAMAS AND AWAY FROM
THE KEYS, BREEZES WILL VEER TO THE NORTH AND FRESHEN BEFORE
GRADUALLY BACKING TO THE SOUTH BY THE END OF THE WEEK.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 82 92 82 92 / 40 30 30 30
MARATHON 83 91 82 91 / 30 30 30 30
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...JAM
AVIATION/NOWCASTS....JAM
DATA ACQUISITION.....JAM
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