595
FOUS30 KWBC 040048
QPFERD
EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
848 PM EDT SAT MAY 3 2025
DAY 1
VALID 01Z SUN MAY 04 2025 - 12Z SUN MAY 04 2025
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE EASTERN U.S. ...
..01Z UPDATE
THE MARGINAL RISK AREA FOR THE SACRAMENTO MOUNTAINS OF NEW MEXICO
WAS REMOVED AS THE SHOWER ACTIVITY OVER THE AREA WANES WITH SUNSET
APPROACHING.
THE MARGINAL FOR THE EASTERN U.S. WAS TRIMMED FROM THE WEST BEHIND
THE EASTWARD MOVING CONVECTION OVER THE SOUTHEAST, AS WELL AS FROM
THE LOWER OHIO VALLEY, WHERE THE RAIN IN INDIANA, ILLINOIS, AND
MISSOURI HAS BEEN MOSTLY STRATIFORM ALL DAY AND HASN'T POSED A
FLASH FLOODING THREAT.
THE MARGINAL IN THE NORTHEAST WAS EXPANDED EASTWARD TO INCLUDE
PHILADELPHIA, NYC, LONG ISLAND, AND BOSTON. POTENT CONVECTION
MOVING NORTHEAST IN THESE AREAS MAY POSE A LOCALIZED FLASH FLOODING
THREAT IN ANY OF THOSE URBAN CENTERS. IT AS ALSO EXPANDED A COUPLE
ROWS OF COUNTIES EAST IN THE CAROLINAS AHEAD OF THE SLOW MOVING
LINE OF STORMS THERE. THOSE STORMS SHOULD WANE WITH NIGHTFALL AS
THEY MOVE INTO EASTERN NORTH CAROLINA.
WEGMAN
DAY 2
VALID 12Z SUN MAY 04 2025 - 12Z MON MAY 05 2025
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PARTS OF THE
EASTERN UNITED STATES AND SOUTHERN ROCKIES AND ADJACENT HIGH
PLAINS...
21Z UPDATE...
NEW MEXICO...
A SLIGHT RISK HAS BEEN RAISED FOR PORTIONS OF EASTERN NM BASED ON A
NOTABLE INCREASE IN QPF FROM THE 12Z GUIDANCE CONSENSUS. SWLY FLOW
OVER TX BRINGS ROBUST GULF MOISTURE UP THROUGH THE SOUTHERN ROCKIES
AND ADJACENT HIGH PLAINS AS A CLOSED LOW DEVELOPS AND STALLS
OVER THE SONORAN DESERT. HEAVY RAIN DEVELOPS IN THE DIURNAL
ACTIVITY THAT THEN PERSISTS OVER THE SOUTHERN HIGH PLAINS WELL INTO
SUNDAY NIGHT AS THE LOW STALLS. THE PW ANOMALY REACHES 2 SIGMA OVER
THIS AREA BY 00Z MONDAY. THE 12Z HREF MEAN SUGGESTS SOME REPEATING
THREATS FOR 1"/HR RATES THROUGH THIS SLIGHT AREA WITH POTENTIAL FOR
2-3" OVER MUCH OF THE AREA. THE MARGINAL RISK WAS EXPANDED TO THE
LOWER FLANKS OF THE SAN JUANS BASED ON UPDATED QPF AND FFG.
GREAT BASIN...
SUNDAY IS THE SECOND DAY FOR THE GREAT BASIN UNDER THE UPPER
TROUGH. WITH PW ANOMALIES OF 2-3 SIGMA OVER NORMAL WITH INSTABILITY
AND FAIRLY LIGHT DEEP LAYER FLOW SHOULD ALLOW SOME REPEATING
ACTIVITY OVER NEVADA AND THE MOJAVE DESERT WHERE A MARGINAL RISK IS
RAISED.
MIDWEST TO NORTHEAST...
THE SLOW MOVING CLOSED LOW EMBEDDED WITHIN A BROADER UPPER TROUGH
CONTINUES TO MAKE ITS WAY EASTWARD SUNDAY. DEEPEST MOISTURE OF
1.25 TO 1.5 INCHES WILL BE EVENTUALLY BE SHUNTED OFF THE MID-
ATLANTIC COAST SUNDAY AFTERNOON, BUT STILL STREAM IN OVER NY BACK
THROUGH NORTHERN OHIO. THE MARGINAL RISK IS MAINTAINED WITH AN
EXPANSION OVER THE DETROIT METRO GIVEN 12Z QPF CONSENSUS ALONG WITH
LOWER FFG.
JACKSON
DAY 3
VALID 12Z MON MAY 05 2025 - 12Z TUE MAY 06 2025
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF WEST
TEXAS...
TEXAS INTO NEW MEXICO...
THE UPPER LOW DRIFTS EAST OVER SOUTHERN AZ MONDAY, CAUSING A MINOR
SHIFT EAST IN DOWNSTREAM RAINFALL COMPARED TO SUNDAY. CONFIDENCE
REMAINS IN A FOCUSED AREA FOR REPEATING HEAVY RAIN SOUTH FROM THE
TX PANHANDLE TO THE NM BORDER WHERE A SLIGHT RISK REMAINS (IT WAS
EXPANDED A BIT WEST THROUGH THE NM BORDER). A BIT OF A LULL IN QPF
IS EXPECTED MONDAY MORNING, BUT DIURNAL INCREASES EXPECTED IN THE
AFTERNOON THAT THEN PERSIST INTO OR THROUGH THE NIGHT. THE PW
ANOMALY IS FORECAST TO EXCEED 2 SIGMA BY 00Z TUESDAY WITH THE 1.25"
PW LINE REACHING THE CAPROCK. THE 12Z QPF CONSENSUS IS FOR 2-4"
OVER A SIZABLE AREA JUST SOUTH OF THE TX PANHANDLE.
MOJAVE DESERT THROUGH SOUTHERN UTAH...
THE BROADENING UPPER LOW OVER AZ AIDS INSTABILITY OVER THE MOJAVE
DESERT THROUGH NORTHERN AZ AND SOUTHERN/CENTRAL UT WHERE A MARGINAL
RISK IS RAISED FOR MONDAY. CONTINUED LIGHT DEEP LAYER FLOW AND PW
ANOMALIES OF 2-3 SIGMA SHOULD ALLOW SLOW MOVING, HEAVY
THUNDERSTORMS OVER THIS AREA WHICH INCLUDES THE SLOT CANYONS OF
SOUTHERN UT.
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...
CLOSED LOW MEANDERS TO THE UPPER OH VALLEY MONDAY NIGHT. CONTINUED
ONSHORE FLOW BRINGS THE THREAT FOR REPEATING LOCALLY HEAVY RAIN
OVER THE NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND WHICH WILL
HAVE SEEN SOME HEAVY RAIN BETWEEN NOW AND THEN. A MARGINAL RISK IS
MAINTAINED.
JACKSON
DAY 1 THREAT AREA: HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/94EPOINTS.TXT
DAY 2 THREAT AREA: HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/98EPOINTS.TXT
DAY 3 THREAT AREA: HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/99EPOINTS.TXT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page