A stacked low pressure system moved eastward from the Ohio Valley to Pennsylvania during the day Thursday, May 19th. Several upper level disturbances rotating around the low aided in the development of numerous showers and thunderstorms.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS ALY wrote it up.
A stacked low pressure system moved eastward from the Ohio Valley to Pennsylvania during the day Thursday, May 19th. Several upper level disturbances rotating around the low aided in the development of numerous showers and thunderstorms. The airmass across east central New York was moist and unstable with a persistent east-southeast flow of low-level moisture off the Atlantic helping to fuel the storms. The thunderstorms that developed trained (repeatedly moved over the same areas) over portions of the mid-Hudson Valley and the eastern Catskills. Flash flooding occurred in parts of Dutchess and Columbia Counties, where several inches of rain fell in a short period of time.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Albany, NY wrote its last area forecast discussion before the first event at May 19, 6:53 PM EST, 2 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ALBANY NY 753 PM EDT THU MAY 19 2011 .SYNOPSIS... A BROAD LOW PRESSURE SYSTEM OVER THE UPPER MID ATLANTIC REGION WILL SLOWLY MOVE NORTH AND EAST WITH THE UNSETTLED WEATHER LASTING INTO THE FIRST HALF OF THE WEEKEND. SCATTERED SHOWERS AND SOME THUNDERSTORMS WILL BE COMMON INTO SATURDAY. THE UPPER LOW WILL MOVE OFF THE EASTERN NEW ENGLAND SEABOARD FRIDAY NIGHT...AS HIGH PRESSURE WILL RIDGE IN BRIEFLY...LATE SATURDAY INTO SUNDAY. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... SEVERE THUNDERSTORM WATCH CANCELED. SOME SCATTERED SHALLOW CONVECTION IS DEVELOPING...AS THE MAIN AREA OF RAIN AND EMBEDDED THUNDER CONTINUES TO BUILD EAST. WILL WATCH FOR HEAVY RAIN AND LOCAL FLOOD THREAT. SOME ADJUSTMENTS TO RAIN CHANCES...AND MINOR ADJUSTMENT TO ALL GRIDS BASED ON CURRENT OBSERVATIONS AND TRENDS. PREV AFD BELOW... WELL...WE HAVE WAITED LONG ENOUGH FOR THE SHOWERS AND STORMS...SO REDUCING CHANCES FOR RAIN THIS EVENING TO SCATTERED IN MOST AREAS. SATELLITE AND RADAR TRENDS AND OUTPUT FROM THE HRRR SUPPORT THIS. SOME INDICATIONS THAT PARTS OF THE WESTERN MOHAWK VALLEY MAY SEE THE LEADING EDGE OF RAIN AFTER SUNSET...BUT IN A WEAKENED STATE. SOME LOCALLY HEAVY RAIN IS POSSIBLE ONCE THE RAIN MOVES INTO THE AREA...BUT AGAIN MAY BE SO LATE THAT THE INTENSITY WILL BE REDUCED...WILL WATCH THIS CLOSELY. INCREASING RAIN CHANCES JUST BARELY TO LIKELY FOR A COUPLE OF HOURS AROUND MIDNIGHT IN MANY AREAS JUST IN CASE THE RAIN AND THUNDER PIVOTS THROUGH OUR REGION BEFORE SUBSIDENCE TAKES OVER AND THE AREAL COVERAGE BEGINS TO DECREASE LATE THIS EVENING AND LATER TONIGHT. THERE IS STILL A MINISCULE CHANCE FOR SEVERE WEATHER IN THE WATCH AREA...SO THE WATCH WILL STAY IN EFFECT TO BE SAFE...AND WILL REEVALUATE BETWEEN 6 PM AND THE WATCH EXPIRATION AT 8 PM FOR POSSIBLE EARLY CANCELATION. PREV AFD BELOW... SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT...BUT THE BEST INSTABILITY AND MOISTURE IS WEST OF THE FORECAST AREA... ASSOCIATED WITH AN APPROACHING UPPER VORT LOBE. THERE ARE SOME ISOLATED SHOWERS WITH LOCALLY HEAVY RAIN OVER OUR REGION...BUT THE AXIS OF MOISTURE AND INSTABILITY IN CENTRAL NY/PA WILL HAVE TO BE WATCHED AS IT GRADUALLY BUILDS EAST THROUGH THIS EVENING. MUCH OF THE DAYTIME HEATING MAY BE GONE BY THE TIME IT ENTERS OUR FORECAST AREA...RESULTING IN MORE OF A LOCALLY HEAVY RAIN...AND URBAN AND SMALL STREAM FLOODING THREAT. IF ANY THUNDERSTORMS DO FORM OVER OUR REGION...IT LOOKS LIKE THE VIL OF THE DAY SHOULD BE IN THE UPPER 40S FOR SEVERE HAIL...AGAIN...WILL KEEP AN EYE ON TRENDS. COVERAGE AND INTENSITY OF CONVECTION WILL DECREASE THROUGH THE NIGHT...BUT MOST AREAS SHOULD SEE MEASURABLE RAIN. PARTIAL CLEARING LIKELY IN AREAS WHERE RAIN EXITS...AND SOME SUBSIDENCE IN THE DRY SLOT SHOULD OCCUR. TEMPERATURES SHOULD FALL INTO THE 50S TONIGHT. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... FIGURING OUT CLOUD COVER AND DEVELOPMENT AND MOVEMENT OF CONVECTION ALWAYS TRICKY PROXIMATE TO THE CENTER OF AN UPPER LOW. BASED ON CHARACTER AND EVOLUTION OF UPPER LOW THE PAST COUPLE OF DAYS...AS THE CENTER OF THE UPPER LOW TRACKS JUST SOUTH OF OUR REGION...PERIODS OF CLOUDS AND SUN IN THE MORNING SHOULD TURN INTO MOSTLY CLOUDY IN THE AFTERNOON WITH DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. UPPER COLD POOL...AND COOLING AT THE BOUNDARY LAYER SHOULD RESULT IN BETTER CHANCES FOR HAIL IN CONVECTION...LOCALLY HEAVY RAIN...AND COOLER TEMPERATURES. SO HIGHS TOMORROW SHOULD BE A COUPLE OR FEW DEGREES COOLER THAN TODAY. ANY LINGERING EVENING CONVECTION SHOULD DISSIPATE AND DECREASE IN COVERAGE THROUGH THE NIGHT. SHOULD BE BETTER CLEARING TOMORROW NIGHT AS BETTER SUBSIDENCE SETS UP WITH UPPER LOW HEADING OFFSHORE. LOWS IN THE 50S...SOME 40S HIGHER ELEVATIONS AND LAKE GEORGE SARATOGA REGION. STILL PERIODS OF CLOUDS AND SUN SATURDAY...BUT WARMING ALOFT AND AT THE BOUNDARY LAYER AS UPPER RIDGING JUST BEGINS TO BUILD IN. ANY SHOWER OR THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE WIDELY SCATTERED. HIGHS SATURDAY SOLIDLY INTO THE 70S. WITH MORE CLEARING SATURDAY NIGHT...LOWS IN THE 50S...40S IN HIGHER ELEVATIONS... LAKE GEORGE AND SARATOGA REGIONS. ON SUNDAY...UPPER RIDGING BUILDS IN MORE RAPIDLY...AND WITH A RELATIVELY STRONG PUSH OF WARM ADVECTION...GUIDANCE AND ENSEMBLES SUGGEST A POTENTIAL LINE OF SCATTERED SHOWERS AND THUNDERSTORMS TRACKING INTO THE REGION SUNDAY AFTERNOON. BASED ON THE MEAN WIND FLOW...FROM THE SOUTHWEST TO WEST...ACTIVITY SHOULD BE QUITE SCATTERED IF IT EVEN DOES DEVELOP AND TRACK INTO OUR AREA SUNDAY AFTERNOON. MIXED CLOUDS AND SUN WILL ALLOW SOME WARMING...WITH HIGHS WELL INTO THE 70S...SOME UPPER 60S IN HIGHER TERRAIN. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... MOS GUIDANCE. ANOTHER UNSETTLED PERIOD...WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. A SERIES OF EMBEDDED LOWER AND MID- LEVEL PROTUBERANCES WITHIN A WEAK FLOW WILL KEEP HUMIDITY... CLOUDS AND SHOWERS AROUND. A COLD FRONT WILL SLIP SLOWLY SOUTH OF THE REGION BY WEDNESDAY...BUT WILL BECOME STATIONARY AS ASSOCIATED LOW PRESSURE TRACKS FROM THE MIDDLE OF THE LOWER 48 TO NEAR MICHIGAN THROUGH TUESDAY. WITH MOIST AIR AND DAYTIME HEATING...SURFACE CAPES SHOULD EASILY EXCEED 1000 J/KG EACH DAY...WITH MLCAPES ALSO PRESENT...THUS THUNDER HAS BEEN INCLUDED IN EACH DAYTIME PERIOD FOR ALL ZONES. DAYTIME HIGH TEMPERATURES WILL BE IN MOSTLY THE 70S...WITH COOLER READINGS IN THE NORTHERN MOUNTAINS. READINGS TUESDAY AND WEDNESDAY SHOULD REACH AROUND 80 DEGREES IN THE MID HUDSON VALLEY. BEHIND THE COLD FRONT ON THURSDAY...HIGHS WILL BACK OFF TO THE MID 60S TO MID 70S RANGE. LOWS WILL RANGE MAINLY FROM THE LOWER OR MID 40S IN THE MOUNTAINS...TO THE MID OR UPPER 50S IN THE VALLEYS. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... FLIGHT CONDITIONS WERE STILL VFR ACROSS MOST OF THE REGION THIS EVENING BUT ARE LIKELY TO DETERIORATE TO MVFR AS SHOWERS AND EMBEDDED THUNDERSTORMS MOVE NORTH AND CURVE WESTWARD TOWARD THE CATSKILLS...SCHOHARIE VALLEY...AND MOHAWK VALLEY. THEY WERE CURRENTLY AFFECTING KPOU...AND ARE LIKELY TO TO GRADUALLY SHIFT EASTWARD AND EFFECT KALB AND KGFL LATER THIS EVENING. BY LATER IN THE EVENING...MVFR CIGS AND VISIBILITY ARE LIKELY TO PREVAIL ACROSS THE REGION. AS THE AIR COOLS...ESPECIALLY TO THE SOUTH... THE CIG AT KPOU IS LIKELY TO BECOME IFR LATER TONIGHT IN LOW MARINE TYPE STRATUS. EASTERLY WINDS THIS EVENING WILL SLACKEN TO LIGHT AND VARIABLE OR CALM FOR THE NIGHTTIME PERIOD. CONDITIONS SHOULD IMPROVE BETWEEN 12Z AND 14Z TO VFR EXCEPT AT KPOU WHERE AN MVFR CIG IS LIKELY TO LINGER A BIT LONGER. AFTER 16Z...SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR OVER THE REGION. AT THIS TIME...WILL ONLY CARRY A VCSH WITH A CB CLOUD GROUP SINCE THE PROBABILITY OF OCCURRENCE AT A TAF SITE IS RATHER LOW. WINDS FRIDAY WILL BE LIGHT FROM THE EAST. OUTLOOK... FRI NIGHT...MVFR WITH BR/LOW STRATUS...CHC -SHRA SAT...VFR/MVFR. CHC -SHRA/TSRA. SUN...VFR. NO SIG WX. MON...VFR/MVFR. CHC -SHRA/TSRA. && .FIRE WEATHER... A BROAD LOW PRESSURE SYSTEM OVER THE UPPER MID ATLANTIC REGION WILL SLOWLY MOVE NORTH AND EAST WITH THE UNSETTLED WEATHER LASTING INTO THE FIRST HALF OF THE WEEKEND. SCATTERED SHOWERS AND SOME THUNDERSTORMS WILL BE COMMON INTO SATURDAY. RELATIVE HUMIDITY VALUES WILL REMAIN HIGH THE NEXT COUPLE OF DAYS WITH WINDS GENERALLY LIGHT UNDER 10 MPH. THE SHOWERS WILL BE MORE SCATTERED INTO SATURDAY...BUT WET FLAG CONDITIONS WILL OCCUR IN SOME LOCATIONS. && .HYDROLOGY... ESOPUS CREEK AT MOUNT MARION IS JUST ABOVE FLOOD STAGE. SOME LOCATIONS HAVE RECEIVED 2 TO 5 INCHES OF RAINFALL IN THE CATSKILLS SINCE SUNDAY. CURRENT SHOWER AND THUNDERSTORM ACTIVITY IN CENTRAL NY/PA COULD PRODUCE AROUND A HALF INCH TO THREE QUARTERS OF AN INCH OF RAIN IN THE CATSKILLS...SCHOHARIE VALLEY AND WESTERN MOHAWK VALLEY THROUGH THIS EVENING. SOME LOCALLY HEAVY RAIN OVER 1 INCH IS POSSIBLE CONTRIBUTING TO SOME SMALL STREAM FLOODING THAT COULD RUN OFF INTO MAIN STEM RIVERS BEYOND TONIGHT. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO SATURDAY. SOME LOCATIONS COULD STILL RECEIVE A HALF AN INCH TO AN INCH OF RAINFALL FROM ANY CONVECTION. THE 3-HR ZONAL FFG VALUES ARE GENERALLY 2-3 INCHES ACROSS MOST OF ERN NY AND WRN NEW ENGLAND....AND THE BREAKS IN THE PCPN HAVE ALLOWED THE GROUND TO SOAK UP THE RAINFALL FAIRLY WELL. A BRIEF PERIOD OF DRY WEATHER IS LIKELY LATE SATURDAY INTO SUNDAY BEFORE A WARM FRONT APPROACHES FROM THE OHIO VALLEY WITH MORE SCATTERED SHOWERS AND THUNDERSTORMS INTO EARLY NEXT WEEK. PLEASE REFER TO PRODUCTS ISSUED BY NWS BTV FOR THE LATEST ON LAKE CHAMPLAIN. HTTP:/WWW.ERH.NOAA.GOV/BTV/LAKE/FLOODINFO.PHP (LOWER CASE). FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && SYNOPSIS...NAS NEAR TERM...NAS SHORT TERM...NAS LONG TERM...ELH AVIATION...RCK FIRE WEATHER...NAS HYDROLOGY...RCK/NAS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ALBANY NY 706 PM EDT THU MAY 19 2011 CTZ001-013-MAZ001-025-NYZ032-033-038>043-047>054-058>061-063>066- 082>084-VTZ013>015-201100- NORTHERN LITCHFIELD-SOUTHERN LITCHFIELD-NORTHERN BERKSHIRE- SOUTHERN BERKSHIRE-NORTHERN HERKIMER-HAMILTON-SOUTHERN HERKIMER- SOUTHERN FULTON-MONTGOMERY-NORTHERN SARATOGA-NORTHERN WARREN- NORTHERN WASHINGTON-SCHOHARIE-WESTERN SCHENECTADY- EASTERN SCHENECTADY-SOUTHERN SARATOGA-WESTERN ALBANY-EASTERN ALBANY- WESTERN RENSSELAER-EASTERN RENSSELAER-WESTERN GREENE-EASTERN GREENE- WESTERN COLUMBIA-EASTERN COLUMBIA-WESTERN ULSTER-EASTERN ULSTER- WESTERN DUTCHESS-EASTERN DUTCHESS-NORTHERN FULTON-SOUTHEAST WARREN- SOUTHERN WASHINGTON-BENNINGTON-WESTERN WINDHAM-EASTERN WINDHAM- 706 PM EDT THU MAY 19 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWESTERN CONNECTICUT...WESTERN MASSACHUSETTS...EAST CENTRAL NEW YORK AND SOUTHERN VERMONT. .DAY ONE...TONIGHT. SCATTERED NON SEVERE THUNDERSTORMS ARE POSSIBLE THIS EVENING ASSOCIATED WITH AN UPPER LOW. THEY WILL MOVE FROM SOUTHEAST TO NORTHWEST AT 20 TO 30 MPH. SOME THE THUNDERSTORMS MAY PRODUCE SMALL HAIL...LESS THAN AN INCH IN DIAMETER...AND LOCALLY HEAVY RAINFALL. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE FRIDAY TO TUESDAY...MAINLY IN THE AFTERNOON AND EARLY EVENING. THERE IS AN ISOLATED THREAT OF SEVERE THUNDERSTORMS PRODUCING LARGE HAIL AND LOCALLY HEAVY RAINFALL FRIDAY AFTERNOON. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
The Albany radar (KENX), 110 km away, was scanning. The volume nearest the first event began at 23:54 UTC.
7 flash flood. Local standard time, as filed.
Flooding was reported at the intersection of Degarmo Hills Road and Myers Corners Road in Wappingers Falls.
Flooding was reported at the intersection of Firemens Way and Noxon Road just east of the City of Poughkeepsie.
Flooding was reported at the intersection of Salt Point Turnpike (Route 115) and North Avenue in Salt Point.
Flooding was reported on Route 44 in Salt Point.
Water was reported over State Route 9 near the Columbiaville Bridge in Stockport.
Fairview Avenue (Route 9) in Greenport Center (Lorenz Park) was reported closed due to flooding.
The intersection of State Route 9H and 66 was reported closed due to flooding.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in New York in 2011Every state in 2011This day in weather historyWarnings in New York, May 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 311117, 311118, 311119, 311120, 311127, 311134, 311133.