804
FXUS01 KWBC 250752
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
352 AM EDT WED SEP 25 2024
VALID 12Z WED SEP 25 2024 - 12Z FRI SEP 27 2024
...HELENE IS FORECAST TO RAPIDLY INTENSIFY TO A MAJOR HURRICANE IN
THE GULF AND BRING LIFE-THREATENING IMPACTS TO FLORIDA AND THE
SOUTHEAST LATE TODAY THROUGH FRIDAY...
...A RARE HIGH RISK OF EXCESSIVE RAINFALL IS IN PLACE FOR THE
SOUTHERN APPALACHIANS THURSDAY-THURSDAY NIGHT WHERE CONSIDERABLE
FLASH/URBAN/RIVER FLOODING AND LANDSLIDES ARE POSSIBLE...
CURRENT TROPICAL STORM HELENE IS FORECAST TO QUICKLY BECOME A
HURRICANE TODAY AND BECOME A MAJOR HURRICANE BEFORE MAKING
LANDFALL ON THURSDAY. A HURRICANE WARNING IS IN EFFECT OVER THE
FLORIDA BIG BEND FOR DAMAGING HURRICANE-FORCE WINDS. HELENE WILL
GROW IN SIZE AS IT STRENGTHENS, SPREADING ITS IMPACTS TO MUCH OF
FLORIDA AND THE SOUTHEAST. THERE IS A DANGER OF LIFE-THREATENING
STORM SURGE ALONG THE ENTIRE WEST COAST OF THE FLORIDA PENINSULA
AND FLORIDA BIG BEND. THE HIGHEST INUNDATION LEVELS ARE EXPECTED
ALONG THE COAST OF THE FLORIDA BIG BEND. PREPARE NOW AND HEED
INSTRUCTIONS FROM LOCAL OFFICIALS ABOUT EVACUATIONS IN THESE
AREAS. PLEASE REFER TO THE NATIONAL HURRICANE CENTER FOR THE
LATEST UPDATES ON THE TRACK AND TIMING OF HELENE.
HELENE WILL ALSO CAUSE SIGNIFICANT RAINFALL AND FLOODING THREATS.
EVEN AHEAD OF HELENE ITSELF, TROPICAL MOISTURE WILL BE PULLED
NORTH INTO THE SOUTHEAST TO SOUTHERN APPALACHIANS TODAY AND
TONIGHT AHEAD OF A SLOW-MOVING UPPER TROUGH/LOW. THIS MOISTURE
WILL POOL ALONG AND AHEAD OF A STALLING FRONT AT THE SURFACE AND
LEAD TO EXCESSIVE RAINFALL. A MODERATE RISK IS IN PLACE IN WPC'S
EXCESSIVE RAINFALL OUTLOOK (ERO) ACROSS PORTIONS OF GEORGIA INTO
THE SOUTHERN APPALACHIANS TODAY INTO TONIGHT WITHIN A BROADER
SLIGHT RISK, IN ADDITION TO SLIGHT RISKS OF FLASH FLOODING IN
PARTS OF THE FLORIDA PENINSULA AND WEST COAST AS HELENE
APPROACHES. TODAY'S RAINFALL IS FORECAST TO CREATE WET ANTECEDENT
CONDITIONS THAT SHOULD LIKELY OVERLAP HEAVY RAIN ALONG HELENE'S
TRACK THURSDAY-FRIDAY. THUS A HIGH RISK OF EXCESSIVE RAINFALL IS
DELINEATED ACROSS THE SOUTHERN APPALACHIANS WHERE UPSLOPE FLOW
SHOULD INCREASE RAIN TOTALS AND VARYING TERRAIN COULD LEAD TO
LANDSLIDES. OVERALL, 5 TO 10 INCHES OF RAIN WITH ISOLATED TOTALS
AROUND 15 INCHES IS FORECAST OVER THE SOUTHEAST. CONSIDERABLE
FLASH AND URBAN FLOODING IS EXPECTED ACROSS PORTIONS OF FLORIDA,
THE SOUTHEAST, SOUTHERN APPALACHIANS, AND THE TENNESSEE VALLEY
WEDNESDAY THROUGH FRIDAY. THIS INCLUDES THE RISK OF LANDSLIDES
ACROSS THE SOUTHERN APPALACHIANS. WIDESPREAD MINOR TO MODERATE
RIVER FLOODING IS LIKELY, AND ISOLATED MAJOR RIVER FLOODING IS
POSSIBLE. ADDITIONALLY, THERE IS A TORNADO THREAT WITH HELENE,
ESPECIALLY ON THE EASTERN SIDE OF THE TRACK. THE STORM PREDICTION
CENTER IS INDICATING A SLIGHT TO ENHANCED RISK OF SEVERE WEATHER,
PRIMARILY FOR TORNADOES, ON THURSDAY INTO THURSDAY NIGHT FOR PARTS
OF FLORIDA INTO GEORGIA AND SOUTH CAROLINA.
ELSEWHERE, SHOWERS AND STORMS ARE ALSO POSSIBLE FARTHER NORTH IN
THE EASTERN U.S. ALONG THE NORTHERN PART OF THE FRONTAL SYSTEM
OVER THE NEXT COUPLE OF DAYS. A COUPLE OF FRONTS PASSING THROUGH
THE NORTHWEST SHOULD LEAD TO SOME PRECIPITATION THERE. MEANWHILE
THE REST OF THE WESTERN U.S. STRETCHING INTO THE NORTH-CENTRAL
U.S. CAN EXPECT DRY CONDITIONS WITH WARMER THAN AVERAGE
TEMPERATURES. THE DESERT SOUTHWEST WILL SEE HIGHS WELL INTO THE
100S, AND 90S ARE POSSIBLE IN THE NORTHERN HIGH PLAINS. SOME
RECORD TEMPERATURES ARE POSSIBLE FOR LOWS AND HIGHS.
TATE
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