037
FXUS01 KWBC 161950
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
350 PM EDT THU MAY 16 2024
VALID 00Z FRI MAY 17 2024 - 00Z SUN MAY 19 2024
...DANGEROUS AND LIFE-THREATENING FLASH FLOODING LIKELY TODAY FOR
PORTIONS OF EASTERN TEXAS AND WESTERN LOUISIANA...
...POTENTIALLY SIGNIFICANT HEAVY RAINFALL THREAT SPREADS INTO
PORTIONS OF SOUTHERN MISSISSIPPI AND WESTERN ALABAMA TOMORROW...
...SWELTERING HEAT CONTINUES ACROSS SOUTH FLORIDA AND SOUTH TEXAS
INTO THIS WEEKEND...
THE MAIN WEATHER STORY TODAY REMAINS THE DANGEROUS AND
LIFE-THREATENING FLASH FLOOD POTENTIAL OVER THE LOWER MISSISSIPPI
VALLEY INTO THE OVERNIGHT HOURS AS WIDESPREAD THUNDERSTORMS BATTER
AREAS WHICH ARE VERY VULNERABLE TO ADDITIONAL RAINFALL. SINCE THE
UPGRADE TO A HIGH RISK (LEVEL 4/4) OF EXCESSIVE RAINFALL LAST
NIGHT, LITTLE HAS CHANGED THIS AFTERNOON REGARDING THE PLACEMENT
AND SEVERITY OF THE FLASH FLOODING THREAT IN EASTERN TEXAS AND
WESTERN LOUISIANA. RADAR ACROSS EAST-CENTRAL TEXAS THIS AFTERNOON
DEPICTS AN EXPANSIVE THUNDERSTORM COMPLEX GROWING ALONG A WARM
FRONT, WITH VERY MOIST AND UNSTABLE AIR FEEDING INTO IT TO SUPPORT
CONTINUOUS STORM DEVELOPMENT THIS AFTERNOON. GOING INTO THE
EVENING AND OVERNIGHT HOURS, REPEATING OF THESE THUNDERSTORMS
CONTAINING VERY HEAVY RAINFALL RATES WITHIN THE COMPLEX WILL LEAD
TO RAINFALL AMOUNTS OF 5-8" TODAY WITHIN THE HIGH RISK AREA OVER
EASTERN TEXAS AND WESTERN LOUISIANA BEFORE THE THUNDERSTORMS
MIGRATE EASTWARD BY TOMORROW MORNING. REMEMBER, HIGH RISKS FOR
EXCESSIVE RAINFALL ARE A BIG DEAL: 1/3 FLOOD RELATED FATALITIES
AND 4/5 FLOOD RELATED DAMAGES OCCUR IN WPC HIGH RISKS, SO PAY
ATTENTION TO THE LATEST WARNING INFORMATION AND NEVER DRIVE OR
WALK INTO FLOODWATERS. FLOODING ASIDE, THE SAME STORMS ARE ALSO
CAPABLE OF PRODUCING A FEW TORNADOES, SEVERE WIND, AND HAIL, WITH
THE STORM PREDICTION CENTER MAINTAINING AN ENHANCED RISK (LEVEL
3/5) OF SEVERE WEATHER OVER MUCH OF THE SAME AREA TODAY.
BY TOMORROW MORNING, THE THREAT OF SIGNIFICANT FLASH FLOODING WILL
SPREAD EAST INTO SOUTHERN MISSISSIPPI AND WESTERN ALABAMA AS THE
AFOREMENTIONED WARM FRONT STALLS OUT OVER THE SOUTHEAST. ONCE
AGAIN, A VERY MOIST AND UNSTABLE ATMOSPHERE APPEARS PRIMED TO
SUPPORT BOUTS OF PROLIFIC HEAVY RAINFALL, WITH MULTIPLE ROUNDS OF
STORMS EXPECTED AS MULTIPLE DISTURBANCES ALOFT TRAVERSE THE AREA.
WHEN COMBINED WITH SATURATED SOILS FROM RECENT HEAVY RAINFALL, A
MODERATE RISK (LEVEL 3/4) IS IN EFFECT TOMORROW WITH AREAL
RAINFALL AMOUNTS UPWARDS OF 2-5" (LOCALLY UP TO 7") POSSIBLE. IT
SHOULD BE NOTED THAT THERE IS SOME UNCERTAINTY WITH WHERE THE
HEAVIEST RAIN FALLS OWING TO HOW THE CURRENT STORMS IN TEXAS
BEHAVE LATER TODAY, SO STAY TUNED FOR ANY ADJUSTMENTS TO THE
FORECAST. ONCE AGAIN, SEVERE WEATHER WILL ALSO BE AN ISSUE SOUTH
OF THE WARM FRONT ACROSS THE GULF STATES, WITH A SLIGHT RISK
(LEVEL 2/5) IN EFFECT FOR FEW TORNADOES, VERY LARGE HAIL, AND
DAMAGING WIND.
THE SAME WARM FRONT DRIVING THE THUNDERSTORMS WILL ALSO CONTRIBUTE
TO SWELTERING HEAT IN SOUTH FLORIDA AND TEXAS. RECENT EXPERIMENTAL
NWS HEATRISK GUIDANCE CONTINUES TO SUGGEST MODERATE TO LOCALLY
MAJOR HEAT RELATED IMPACTS WILL CONTINUE ACROSS THESE AREAS AT
LEAST THROUGH SATURDAY DUE TO THE COMBINATION OF HEAT INDICES
ECLIPSING 100 DEGREES, WITH LITTLE OVERNIGHT RELIEF EXPECTED.
ASHERMAN
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HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP
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