An area of low pressure moved southwest to northeast across northern New York. One to two inches of rain fell across the northern Adirondacks on top of saturated soils and elevated rivers.
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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 BTV wrote it up.
An area of low pressure moved southwest to northeast across northern New York. One to two inches of rain fell across the northern Adirondacks on top of saturated soils and elevated rivers.
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 Burlington, VT wrote its last area forecast discussion before the first event at May 4, 2:33 AM EST, 7 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 333 AM EDT WED MAY 4 2011 .SYNOPSIS... SLOW MOVING FRONTAL BOUNDARY AND ASSOCIATED WAVE OF LOW PRESSURE WILL CONTINUE TO BRING RAIN...HEAVY AT TIMES...THIS MORNING WITH RAIN GRADUALLY EXITING EAST OF THE REGION THIS AFTERNOON. AN ASSOCIATED UPPER LEVEL LOW WILL THEN PROGRESS EASTWARD ACROSS THE NORTH COUNTRY TONIGHT AND THURSDAY...WITH CONTINUED CLOUDY SKIES AND NUMEROUS RAIN SHOWERS. FOR THE MOUNTAINS...UNSEASONABLY COOL TEMPERATURES WITH THE UPPER LOW WILL BRING PERIODS OF SNOW SHOWERS FOR THE SUMMITS TONIGHT AND DURING THE DAY THURSDAY. DRIER AND PARTLY SUNNY CONDITIONS ARE EXPECTED FRIDAY AS UPPER LEVEL LOW DEPARTS TO THE NORTH OF THE REGION. LOOK FOR UNSEASONABLY COOL DAYTIME TEMPERATURES THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 312 AM EDT WEDNESDAY...MERIDIONAL 500MB TROUGH EXTENDING EARLY THIS MORNING FROM THE CENTRAL GREAT LAKES REGION SOUTHWARD TO THE CENTRAL GULF COAST STATES WILL GRADUALLY EVOLVE INTO A CLOSED 500MB LOW AS IT MIGRATES SLOWLY EWD INTO CENTRAL AND NORTHERN NY AND NEW ENGLAND TONIGHT. ASSOCIATED STRONG SFC FRONTAL ZONE BISECTS THE NORTH COUNTRY FROM SSW-NNE THIS MORNING...AND WITH MID-UPR LEVEL FLOW PERPENDICULAR TO THE BNDRY IS RESULTING IN CONTINUED RAINFALL ACROSS MUCH OF OUR REGION THIS MORNING. FRONTAL BNDRY WILL MAKE SLOW EWD PROGRESS...AND BACK EDGE OF FRONTAL PCPN HAS ALREADY MOVED EAST OF ST. LAWRENCE COUNTY NY. RAINFALL AMTS OF 1-1.5 INCHES HAVE ALREADY OCCURRED ACROSS MUCH OF NRN NY AND NWRN VT /INCLUDING 1.11" AT BTV AS OF 1AM THIS MORNING/...AND ANTICIPATE ANOTHER 0.25-0.50" ALONG THE ERN SLOPES OF THE ADIRONDACKS AND ACROSS THE CHAMPLAIN VALLEY THRU THIS MORNING. RAINFALL IS JUST DEVELOPING INTO ERN 1/3RD OF VERMONT EARLY THIS MORNING...AND PERIODS OF MODERATE RAINFALL CAN BE ANTICIPATED THRU THE REMAINDER OF THIS MORNING WITH INCREASING FRONTOGENESIS FORCING FOR ASCENT. WILL CONTINUE MENTION OF RAIN HEAVY AT TIMES THIS MORNING FOR ERN SECTIONS...AND WILL CONTINUE FLOOD WATCH ACROSS THE REGION THRU TONIGHT. FURTHER HYDROLOGICAL DETAILS CAN BE FOUND IN HYDRO SECTION BELOW. 2-METER TEMPERATURES RANGE WIDELY FROM THE LOW 60S EARLY THIS MORNING IN SERN VT...TO THE MID 40S ACROSS THE NORTHERN ADIRONDACKS AND ST. LAWRENCE VALLEY. WITH AFOREMENTIONED UPR LOW DEVELOPING ACROSS NRN NY LATE TODAY AND CONTINUED OVERCAST SKIES...TEMPERATURES WILL NOT BE CLIMBING MUCH...GENERALLY REMAINING IN THE MID-UPR 40S ACROSS NRN NY AND ONLY LOW 50S FOR HIGHS IN THE CHAMPLAIN VALLEY. COOLER TEMPERATURES WILL FILTER EWD ACROSS VERMONT THROUGHOUT THE DAYLIGHT HRS AS FRONTAL BNDRY SHIFTS EWD WITH TEMPS GENERALLY SLOWLY FALLING THRU THE DAY ACROSS CENTRAL/ERN PORTIONS OF THE CWA. FOR TONIGHT...SFC-850MB BAROCLINIC ZONE SHIFTS EAST OF THE FORECAST AREA BUT CLOSED MID-UPR TROPOSPHERIC LOW BRINGS CONTINUED CHANCES FOR SHOWERY PRECIPITATION. COOLING VERTICAL TEMPERATURE PROFILES WITH 850MB TEMPS DOWN TO -4C ACROSS THE NRN GREEN MTNS AND NRN ADIRONDACKS BY 12Z THURSDAY WILL ALLOW RAIN SHOWERS TO GRADUALLY MIX AND CHANGE TO SNOW SHOWERS AT ELEVATIONS ABOVE 1500 FT. SOME LIGHT SNOW ACCUMULATION IS POSSIBLE AT SUMMIT ELEVATIONS ABOVE 2000-2500 FEET...GENERALLY AN 1" OR SO BY 12Z THURSDAY...BUT TOTALING 1-3" WITH ADDITIONAL SNOW SHOWER ACTIVITY DURING THE DAY THURSDAY FOR THE HIGHER SUMMITS OF VERMONT AND NRN NY. && .SHORT TERM /THURSDAY THROUGH FRIDAY/... AS OF 312 AM EDT WEDNESDAY...CLOSED 500MB LOW WILL BE IN CONTROL OF THE WEATHER ACROSS THE NORTH COUNTRY THURSDAY AND THURSDAY NIGHT...BRINGING GENERALLY CLOUDY SKIES...COOL TEMPERATURES AND NUMEROUS RAIN SHOWERS ESPECIALLY ACROSS NRN SECTIONS OF THE FCST AREA WITH GOOD WRAPAROUND WITH HIGH 1000-500MB LAYER RH VALUES. THE HIGHER ELEVATIONS ABOVE 2000 FEET WILL CONTINUE TO SEE A MIX OF RAIN AND SNOW SHOWERS WITH SOME ADDITIONAL ACCUMULATION /1-2"/ FOR THE HIGHEST SUMMITS ACROSS THE REGION. GENERALLY STAYED NEAR MOS CONSENSUS ON TEMPERATURES. SFC WINDS WILL GENERALLY BE NWLY...10-15 MPH DURING THE DAYLIGHT HRS THURSDAY. ON FRIDAY...GENERALLY UNDERCUT MOS POPS AS UPR LOW SHOULD BE LIFTING OUT OF THE REGION. WENT WITH A DRY FCST AND SHOULD BE SOME POTENTIAL FOR A BIT OF SUNSHINE FRIDAY AFTERNOON. TEMPERATURES WILL REMAIN BELOW SEASONAL LEVELS WITH HIGHS GENERALLY IN THE MID- UPR 50S...EXCEPT LOWER 50S FOR NERN VT. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AS OF 333 AM EDT WEDNESDAY...UPPER LOW OVER SE QUEBEC LIFTS INTO NE QUEBEC GOING INTO THE WEEKEND. THIS IS GOING TO SET UP ZONAL FLOW OVER THE AREA INTO MONDAY BFR LARGE UPPER RIDGE FORMS OVER THE SE STATES RIGHT INTO MIDWEEK NEXT WEEK. WK SFC LOW REFLECTIONS WILL FOLLOW THRU THE AREA ALONG WESTERLY FLOW EARLY ON...THEN WORKING OVER UPPER RIDGE AND ACROSS THE OHIO VALLEY/NE REGION. W/ SFC HIGH PRESSURE SHOWING SIGNS IN MDLS THAN PREV COUPLE OF DAYS...GD CHANCE FOR SOME CLRING AND THUS AN INCR IN TEMPS...ESPECIALLY DURNG THE DAYTIME HRS. HAVE ADJUSTED TEMPS ACCORDINGLY BASED ON EXPECTED CLDS/PRECIP. OTHERWISE FOR PRECIP...KEPT POPS IN CHANCE CATEGORY...MAINLY RAIN W/ SPOTS OVER HIR ELEV WHERE -SW MAY MIX IN. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... THROUGH 06Z THURSDAY...ALL FORECAST SITES WILL MAINLY SEE A MIX OF IFR/MVFR CEILINGS RANGING FROM BKN-OVC005 UP TO BKN030. SOME LIFR CEILINGS DOWN TO OVC003 FOR A FEW HRS. VSBY IN RW/FG WILL MAINLY STAY BETWEEN 3-6SM...BUT AS PRECIP ENDS SLOWLY FROM W TO E...FG WILL BECM MORE PROMINENT...W/ VSBY 1-3SM...ESPECIALLY SLK/MPV. LGT/VAR WINDS WILL BECM NNW/NNE 5-10KTS. OUTLOOK 06Z THURSDAY THROUGH SUNDAY...THE DEVELOPMENT OF MID/UPPER LVL TROF WL CONT TO PRODUCE SHOWERS WITH OCCASIONAL MVFR/IFR CONDITIONS THRU 18Z THURS...ESPECIALLY AT MPV/SLK. A SLOW IMPROVING TREND IS ANTICIPATED TWD THE WEEKEND...WITH VFR CONDITIONS DEVELOPING. SOME MTN RAIN MIXED WITH SNOW WL BE POSSIBLE LATE WEDS INTO THURS...WITH A PERIOD OF IFR/LIFR CONDITIONS POSSIBLE AT SLK WEDS NIGHT INTO THURSDAY MORNING. WINDS WL GENERALLY BE NORTHWEST 10 TO 15KNTS WITH LOCALIZED HIGHER GUSTS. && .HYDROLOGY... AS OF 300 AM EDT WEDNESDAY... WILL CONTINUE FLOOD WATCH THRU 06Z THURSDAY. OVERALL...QPF IS PANNING OUT ABOUT AS EXPECTED WITH HIGHEST RAINFALL TOTALS ACROSS NRN NY INTO NWRN VT. THRU 06Z WED...GENERALLY 1.5-1.75" ACROSS THE NRN ADIRONDACKS...AND 1.0-1.5" ACROSS FAR NWRN VT AND PORTIONS OF THE ST. LAWRENCE VALLEY. ADDITIONAL RAINFALL IS EXPECTED TODAY ACROSS VERMONT...BUT GENERAL WEAKENING TREND OF FRONTAL ZONE SUGGESTS GREATEST FLOODING IMPACTS WILL BE ACROSS NWRN VT...LAKE CHAMPLAIN...AND NRN NY. FLOOD WARNING IN EFFECT FOR AUSABLE FORKS /ASFN6/ WITH FLOOD ADVISORY FOR NRN NY COUNTIES THRU 0930Z. WE ARE ALSO CLOSELY MONITORING THE SARANAC RIVER AT PBG AS WELL AS THE MISSISQUOI BASIN WITH MINOR FLOODING POSSIBLE AT THOSE LOCATIONS LATER THIS MORNING. LAKE CHAMPLAIN WILL REMAIN QUITE PROBLEMATIC WITH A GOOD PORTION OF THE BASIN SEEING RAINFALL AMOUNTS 1-2". THE FORECAST IS FOR LAKE CHAMPLAIN TO REACH 103' LEVEL DURING THE DAY THURSDAY...WHICH WOULD BE A NEW RECORD. LAKE LEVEL RECORDS DATE BACK TO 1907. THUS...CONTINUED WIDESPREAD IMPACTS ALONG LAKESHORE ROADS/BIKEPATHS...AND POSSIBLY EVEN U.S. ROUTE 2 BETWEEN SANDBAR STATE PARK AND GRAND ISLE AS WATER INCHES HIGHER POSSIBLY ACROSS THE CAUSEWAY NEXT 24-48 HOURS. WILL CONTINUE TO MONITOR. TO MEDIA PARTNERS AND STATE OFFICIALS...PLEASE RELAY ANY NEW FLOODING TO US HERE AT THE NWS FOR DISSEMINATION IN HYDRO STATEMENTS AND POSSIBLE WARNINGS. && .MARINE... AS OF 300 AM EDT WEDNESDAY...LAKE CHAMPLAIN REMAINS NEAR A RECORD FLOOD LEVEL TODAY...AND THE LAKE LEVEL IS PROJECTED TO GRADUALLY RISE TO 103.0 FEET BY THURSDAY OWING TO RUNOFF FROM MODERATE TO HEAVY RAINFALL THROUGHOUT THE CHAMPLAIN BASIN SINCE TUESDAY. MANY HAZARDS SUCH AS BREAKWATER AND OTHER ROCKS OR OBSTRUCTIONS MAY BE OBSCURED BY THE HIGH WATER LEVELS. IN ADDITION...HIGH FLOW FROM RIVERS OVER THE PAST FEW WEEKS HAS DELIVERED PLENTY OF DEBRIS INTO THE LAKE. LASTLY...THE LAKE TEMPERATURE IS ONLY IN THE UPPER 30S. DUE TO ALL OF THE ABOVE FACTORS...BOATING IS DISCOURAGED AT THIS TIME. WINDS WILL BE LIGHT IN VICINITY OF THE FRONTAL BOUNDARY TODAY...BUT WILL BE INCREASING FROM THE NORTHWEST TONIGHT AND GENERALLY NORTH 10-20 KNOTS DURING THE DAY THURSDAY. THIS WILL RESULT IN SOME WAVE ACTION OF 1 TO 2 FEET AND POSSIBLE MINOR EROSION ALONG NORTH FACING SHORELINE. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FLOOD WATCH THROUGH LATE TONIGHT FOR VTZ001>012-016>019. NY...FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ026>031-034-035-087. && SYNOPSIS...BANACOS NEAR TERM...BANACOS SHORT TERM...BANACOS LONG TERM...JN AVIATION...WGH/JN/BOYD HYDROLOGY...BTV MARINE...BTV
The national radar mosaic for the moment the first event began.
1 flood. Local standard time, as filed.
Runoff from prolonged heavy rainfall of one to two inches in the East Branch Ausable River basin caused minor flooding. The river gage at Ausable Forks to exceed flood stage at 2:40 AM EST on May 4, and crested at a stage of 7.15 feet on May 4 at 04:30 AM EsT.
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: 309012.