The combination of an upper level short wave and a surface trough triggered scattered showers and thunderstorms across the area. Some thunderstorms produced very heavy rainfall that resulted in localized flash flooding in New Haven county.
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 OKX wrote it up.
The combination of an upper level short wave and a surface trough triggered scattered showers and thunderstorms across the area. Some thunderstorms produced very heavy rainfall that resulted in localized flash flooding in New Haven county.
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 New York, NY wrote its last area forecast discussion before the first event at Aug 1, 12:47 PM EST, 1 hour 8 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 147 PM EDT WED AUG 1 2012 .SYNOPSIS... A WEAK FRONT APPROACHES AND DISSIPATES OVER THE REGION TONIGHT. WEAK HIGH PRESSURE WILL GENERALLY BE IN CONTROL LATE THIS WEEK INTO THE FIRST HALF OF THE WEEKEND. A STRONG FRONTAL SYSTEM WILL AFFECT THE AREA LATE SUNDAY INTO MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... CONVECTION ONGOING ACROSS NYC METRO...WITH HEAVY DOWNPOURS THE MAIN ISSUE THIS AFTERNOON. WILL CONTINUE TO MENTION THE CHC FOR HEAVY RAINS WITH PW VALUES AROUND 1.75 IN AND THE WEAK FLOW ALOFT AS CORFIDI VECTORS REMAIN LESS THAN 15 KTS. INSTABILITY HAS INCREASED TO BETWEEN 1000-1500 J/KG...THOUGH 0-6KM SHEAR REMAINS FAIRLY LOW...LESS THAN 20 KTS...SO NOT EXPECTING MUCH IN THE DEVELOPMENT OF ANY STRONG TO SEVERE THUNDERSTORMS. NEAR NORMAL TEMPS EXPECTED TODAY DESPITE WARMING 850MB TEMPS WITH PERSISTENT CLOUD COVER EXPECTED ALONG WITH THE PRECIP. USED A BLEND MAV/MET FOR HIGH TEMPS...BRINGING TEMPS TO THE LOWER TO MID 80S. THERE IS A MODERATE RISK FOR RIP CURRENT THIS AFTERNOON AND EVENING DUE TO PERSISTENT AND INCREASING SOUTHERLY WINDS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... THE AFOREMENTIONED COLD FRONT REACHES THE CWA BY TONIGHT...BUT THE MODELS ACTUALLY HAVE IT WASHING OUT IN THE NORTHEAST...WITH ONLY A MINOR WEAK TROUGH PASSING THROUGH. ALOFT...THE UPPER LEVEL TROUGH AXIS BASICALLY SPLITS THE CWA...KEEPING THE HIGHER FORCING THOUGH OVER THE WESTERN HALF OF THE CWA. WILL KEEP CHC POPS IN FOR THE FIRST COUPLE OF HOURS...THEN GRADUALLY DIMINISH BY 06Z AS THE FORCING WEAKENS. NOT EXPECTING MUCH OF ANY FLOODING/SEVERE THREAT WITH PW VALUES DROPPING BELOW 1.5 INCHES...AND CAPE VALUES TOPPING OUT AROUND 500 J/KG. WILL CONTINUE MENTION OF ISO TSTORM. WEAK LOW PRESSURE HOVERS AROUND THE NORTHEAST THROUGH THURSDAY...WITH THE MODELS DEVELOPING ANOTHER SFC LOW OFF THE DELMARVA COAST DURING THE DAY AND TRACKING IT TO THE NORTHEAST BY THURS NIGHT. THE 00Z GFS REMAINS THE OUTLIER ON THE TIMING...SO SIDED MORE WITH THE CMC AND NAM TO ACCOUNT FOR THE TIMING OF THE WIND SHIFTS THURS. WITH A WEAK SHORTWAVE PASSING THROUGH AS WELL THURS...COULD SEE THE POTENTIAL FOR SOME DIURNAL DEVELOPMENT OF SHOWERS AND ISO TSTORM. ALSO NOT EXPECTING MUCH IN FLOODING/SEVERE POTENTIAL FOR THIS ROUND OF STORMS AT THIS TIME. 850MB TEMPS KEEP INCREASING TONIGHT INTO TOMORROW...AND WITH SCT OF THE SKIES EXPECTED TOM AFTN...WENT AHEAD AND BEGAN GRADUALLY INCREASING OVERNIGHT LOWS AND DAYTIME HIGHS. MAV SEEMED A BIT WARMER AS THE OUTLIER...SO WENT WITH A MET/MOS BLEND. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... AN ACTIVE PATTERN WILL CONTINUE WITH THE WESTERLIES ALONG THE U.S./CANADIAN BORDER AND FLUCTUATIONS IN THE MEAN TROF ACROSS EASTERN CANADA...THE GREAT LAKES...AND NE. AT THE ONSET OF THE PERIOD...THE UPPER TROUGH ALONG THE EAST COAST WEAKENS AND FILLS WITH HEIGHT RISES THROUGH THE UPCOMING WEEKEND. THE SUBTROPICAL RIDGE RETROGRADES ACROSS THE WESTERN ATLANTIC TO A POSITION JUST OFF THE EASTERN SEABOARD THIS WEEKEND. THIS WILL MEAN VERY WARM...HUMID CONDITIONS FOR MUCH OF THE PERIOD. GLOBAL MODELS ARE IN GENERALLY GOOD AGREEMENT WITH LARGE SCALE FEATURES AND THE SENSIBLE WEATHER THROUGH THE WEEKEND. DIFFERENCES ARISE IN THE MAGNITUDE AND TIMING OF AN UPPER TROUGH APPROACHING ON SUNDAY AND PASSING THOUGH ON MONDAY. IN GENERAL...TIMING HAS SPED UP...WITH A STRONG COLD FRONT PASSING THROUGH BY MONDAY AFTERNOON. LEANED TOWARD THE 00Z ECMWF TIMING....BUT THE GLOBAL GEM AND GFS ARE EVEN QUICKER. PRIOR TO NEXT MON...GENERALLY LOOKING AT HOT AND HUMID CONDITIONS... WITH DAYTIME HIGHS IN THE LOW TO MID 90S FRI...AND THEN 85 TO 90 SAT AND SUN...AND LOWS 70 TO 75. DEW POINTS WILL BE AROUND 70 WITH HEAT INDICES APPROACHING 95 FOR METRO NY BOTH FRI AND SAT. THIS IS SEVERAL DEGREES ABOVE CLIMATOLOGICAL NORMS...AND IN SOME CASES UP TO 8 DEGREES ABOVE NORMAL FOR FRI. CONDITIONS GRADUALLY COOL DOWN AND DRY OUT LATE MON INTO TUE BEHIND THE COLD FRONT. AS FOR CONVECTION...IT LOOKS TO BE MAINLY DIURNALLY DRIVEN EACH AFTERNOON WITH A MODERATELY UNSTABLE...WEAKLY SHEARED ENVIRONMENT. ISOLATED STRONG THUNDERSTORMS COULD NOT BE RULED OUT. BEST CHANCE LOOKS TO BE ACROSS THE INTERIOR. POTENTIAL EXISTS FOR A MORE ORGANIZED EVENT ON MON WITH HEIGHT FALLS...A STRENGTHENING VERTICAL WIND PROFILE...AND A COLD FRONT. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... A WEAK FRONTAL BOUNDARY WILL SLOWLY TRACK THRU THE REGION THIS AFTERNOON AND TONIGHT. GOOD COVERAGE OF HEAVY SHOWERS AND THUNDERSTORMS THIS AFTERNOON. GENERALLY VFR OUTSIDE OF CONVECTION. BY EVENING...COVERAGE AND INTENSITY SHOULD DIMINISH. COULD SEE FOG...ESPECIALLY WHERE ABUNDANT RAINFALL OCCURRED OUTSIDE NYC METRO TERMINALS. AS FOR WINDS...SOUTH WINDS AROUND 10 KTS THIS AFTERNOON LIGHTEN THIS EVENING. WINDS COULD VARY IN ANY THUNDERSTORMS. LIGHT WINDS AND VFR CONDITIONS ARE ANTICIPATED THURSDAY MORNING. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KEWR FCSTER COMMENTS: WINDS MAY VARY IN THUNDERSTORM ACTIVITY. TIMING OF THUNDER COULD LINGER UNTIL 22 OR 23Z. KJFK FCSTER COMMENTS: WINDS MAY VARY IN THUNDERSTORM ACTIVITY. TIMING OF THUNDER COULD LINGER UNTIL 22 OR 23Z. KLGA FCSTER COMMENTS: WINDS MAY VARY IN THUNDERSTORM ACTIVITY. TIMING OF THUNDER COULD LINGER UNTIL 22 OR 23Z. KTEB FCSTER COMMENTS: WINDS MAY VARY IN THUNDERSTORM ACTIVITY. TIMING OF THUNDER COULD LINGER UNTIL 22 OR 23Z. KHPN FCSTER COMMENTS: WINDS MAY VARY IN THUNDERSTORM ACTIVITY. TIMING OF THUNDER COULD LINGER UNTIL 22 OR 23Z. KISP FCSTER COMMENTS: A SHOWER OR THUNDERSTORM IS POSSIBLE THROUGH THE REMAINDER OF THE AFTERNOON. OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY... .THU AFTERNOON-SAT...PATCHY GROUND FOG POSSIBLE EACH MORNING...ESPECIALLY OUTLYING AIRPORTS. A FEW AIRMASS TSTMS POSSIBLE EACH DAY. .SUN...TSTMS POSSIBLE WITH AN APPROACHING COLD FRONT. .MON...POSSIBLE RETURN TO VFR DEPENDING ON SPEED OF COLD FRONT. && .MARINE... SUB-SCA CONDITIONS EXPECTED ON ALL WATERS THROUGH THURSDAY. THE ONLY CONCERN WOULD BE THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON THAT COULD GENERATE WIND GUSTS UP TO AROUND 35 KTS. OTHERWISE...WILL SEE A STEADY SWLY-SLY FLOW BETWEEN 5 AND 10 KTS. GENERALLY SUB SCA CONDS EXPECTED THU NIGHT THRU SUN WITH A S/SW FLOW AT 10 TO 15 KT. MARGINAL SCA CONDITIONS WILL BE POSSIBLE ON THE OCEAN WATERS SUN INTO MON AHEAD OF A STRONG COLD FRONT WITH POSSIBLE GUSTS UP TO 20 KT. SCT SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN POSSIBLE THROUGH THE PERIOD...ESPECIALLY DURING THE AFTERNOON HOURS...WHICH COULD PRODUCE GUSTY WINDS. && .HYDROLOGY... FLASH FLOOD THREAT CONTINUES WITH RAINFALL RATES OF UP TO 2 INCHES PER HOUR POSSIBLE IN STRONGER/MORE ORGANIZED CONVECTION. MAINLY ISOLATED DIURNAL SHRA/TSRA ACTIVITY IS EXPECTED THU THRU SAT WHICH COULD CAUSE LOCAL URBAN AND POOR DRAINAGE FLOODING. INCREASING SHRA/TSTM ACTIVITY SUN AND MORE SO MONDAY AHEAD AN APPROACHING FRONTAL SYSTEM PRESENTS AN INCREASED POTENTIAL FOR URBAN AND POOR DRAINAGE FLOODING AND A LOW END FLASH FLOOD THREAT. && .TIDES/COASTAL FLOODING... THE THREAT FOR MINOR COASTAL FLOODING WILL BE LOWER TONIGHT AS THE PREDICTED ASTRONOMICAL HIGH TIDES ARE EXPECTED TO BE SLIGHTLY LOWER THAN TUES NIGHT. THE MINOR FLOOD LEVELS WERE BARELY REACHED IN ISOLATED AREAS TUES NIGHT...AND WITH THE LOWER PREDICTED HIGH TIDES FOR TONIGHT...NOT EXPECTING MINOR LEVELS TO BE MET. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && SYNOPSIS...SEARS/DW NEAR TERM...SEARS/PW SHORT TERM...SEARS LONG TERM...DW AVIATION...PW MARINE...SEARS/DW HYDROLOGY...GOODMAN/SEARS TIDES/COASTAL FLOODING...
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE NEW YORK NY 631 AM EDT WED AUG 1 2012 CTZ005-006-009-NJZ002-004-006-103>108-NYZ067>075-176>179-021045- NORTHERN FAIRFIELD-NORTHERN NEW HAVEN-SOUTHERN FAIRFIELD- WESTERN PASSAIC-EASTERN PASSAIC-HUDSON-WESTERN BERGEN-EASTERN BERGEN- WESTERN ESSEX-EASTERN ESSEX-WESTERN UNION-EASTERN UNION-ORANGE- PUTNAM-ROCKLAND-NORTHERN WESTCHESTER-SOUTHERN WESTCHESTER- NEW YORK (MANHATTAN)-BRONX-RICHMOND (STATEN ISLAND)-KINGS (BROOKLYN)- NORTHERN QUEENS-NORTHERN NASSAU-SOUTHERN QUEENS-SOUTHERN NASSAU- 631 AM EDT WED AUG 1 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN CONNECTICUT...NORTHEAST NEW JERSEY AND SOUTHEAST NEW YORK. .DAY ONE...TODAY AND TONIGHT. SHOWERS AND THUNDERSTORMS POSSIBLE WITH AN APPROACHING FRONT THIS AFTERNOON COULD PRODUCE HEAVY RAIN AND LOCALIZED FLASH FLOODING. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME THAT WOULD MEET NATIONAL WEATHER SERVICE WARNING CRITERIA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED. && THIS HAZARDOUS WEATHER OUTLOOK PROVIDES A SUMMARY OF POTENTIAL WIDESPREAD HAZARDOUS WEATHER EVENTS THAT MAY REACH NWS WARNING CRITERIA. MOST LONG FUSED NWS WATCHES...WARNINGS AND ADVISORIES IN EFFECT ARE HIGHLIGHTED. PLEASE REFER TO THE LATEST NWS FORECASTS FOR WEATHER NOT MEETING NWS WARNING CRITERIA. ANZ335-338-355-021045- LONG ISLAND SOUND WEST OF NEW HAVEN CT/PORT JEFFERSON NY- NEW YORK HARBOR-SANDY HOOK NJ TO FIRE ISLAND INLET NY OUT 20 NM- 631 AM EDT WED AUG 1 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS. .DAY ONE...TODAY AND TONIGHT. SCATTERED THUNDERSTORMS THIS AFTERNOON COULD PRODUCE GUSTY WINDS UP TO AROUND 35 KTS AND HEAVY RAIN WITH VSBY 1 NM OR LESS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME THAT WOULD MEET NATIONAL WEATHER SERVICE WARNING CRITERIA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. && THIS HAZARDOUS WEATHER OUTLOOK PROVIDES A SUMMARY OF POTENTIAL WIDESPREAD HAZARDOUS WEATHER EVENTS THAT MAY REACH NWS WARNING CRITERIA. MOST LONG FUSED NWS WATCHES...WARNINGS AND ADVISORIES IN EFFECT ARE HIGHLIGHTED. PLEASE REFER TO THE LATEST NWS FORECASTS FOR WEATHER NOT MEETING NWS WARNING CRITERIA. CTZ007-008-010>012-NYZ078>081-021045- NORTHERN MIDDLESEX-NORTHERN NEW LONDON-SOUTHERN NEW HAVEN- SOUTHERN MIDDLESEX-SOUTHERN NEW LONDON-NORTHWESTERN SUFFOLK- NORTHEASTERN SUFFOLK-SOUTHWESTERN SUFFOLK-SOUTHEASTERN SUFFOLK- 631 AM EDT WED AUG 1 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN CONNECTICUT AND SOUTHEAST NEW YORK. .DAY ONE...TODAY AND TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME THAT WOULD MEET NATIONAL WEATHER SERVICE WARNING CRITERIA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. && THIS HAZARDOUS WEATHER OUTLOOK PROVIDES A SUMMARY OF POTENTIAL WIDESPREAD HAZARDOUS WEATHER EVENTS THAT MAY REACH NWS WARNING CRITERIA. MOST LONG FUSED NWS WATCHES...WARNINGS AND ADVISORIES IN EFFECT ARE HIGHLIGHTED. PLEASE REFER TO THE LATEST NWS FORECASTS FOR WEATHER NOT MEETING NWS WARNING CRITERIA. ANZ330-340-345-350-353-021045- LONG ISLAND SOUND EAST OF NEW HAVEN CT/PORT JEFFERSON NY- PECONIC AND GARDINERS BAYS- SOUTH SHORE BAYS FROM JONES INLET THROUGH SHINNECOCK BAY- MORICHES INLET NY TO MONTAUK POINT NY OUT 20 NM- FIRE ISLAND INLET NY TO MORICHES INLET NY OUT 20 NM- 631 AM EDT WED AUG 1 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS. .DAY ONE...TODAY AND TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME THAT WOULD MEET NATIONAL WEATHER SERVICE WARNING CRITERIA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. && THIS HAZARDOUS WEATHER OUTLOOK PROVIDES A SUMMARY OF POTENTIAL WIDESPREAD HAZARDOUS WEATHER EVENTS THAT MAY REACH NWS WARNING CRITERIA. MOST LONG FUSED NWS WATCHES...WARNINGS AND ADVISORIES IN EFFECT ARE HIGHLIGHTED. PLEASE REFER TO THE LATEST NWS FORECASTS FOR WEATHER NOT MEETING NWS WARNING CRITERIA.
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE NEW YORK NY
1245 PM EDT WED AUG 01 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1225 PM FLASH FLOOD KEW GARDENS 40.72N 73.83W
08/01/2012 QUEENS NY BROADCAST MEDIA
E GRAND CENTRAL PKWY AT KEW GARDENS INTERCHANGE CLOSED
DUE TO FLOODING
1235 PM FLASH FLOOD 1 ESE CLEARVIEW EXPRESS 40.74N 73.78W
08/01/2012 QUEENS NY BROADCAST MEDIA
LI EXPY AT FRANCIS LEWIS BLVD CLOSED DUE TO FLOODING
1237 PM FLASH FLOOD 1 ENE RICHMOND HILL 40.70N 73.82W
08/01/2012 QUEENS NY BROADCAST MEDIA
S VAN WYCK EXPY AT HILLSIDE AVE CLOSED DUE TO FLOODING
&&
PICCASPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
227 PM EDT WED AUG 1 2012
NYZ069-070-011915-
NORTHERN WESTCHESTER-ROCKLAND-
227 PM EDT WED AUG 1 2012
...STRONG THUNDERSTORM WILL IMPACT ROCKLAND AND WESTCHESTER
COUNTIES...
AT 223 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR NANUET...AND MOVING NORTH AT 10 MPH.
THIS STORM WILL BE...
4 MILES WEST OF UPPER NYACK BY 240 PM.
NEAR NEW CITY BY 245 PM.
NEAR POMONA BY 255 PM.
NEAR HAVERSTRAW BY 300 PM.
5 MILES SOUTH OF PEEKSKILL BY 315 PM.
SMALL HAIL...AND WINDS UP TO 40 MPH ARE EXPECTED WITH THIS STORM. IN
ADDITION...HEAVY RAIN IS OCCURRING WITH THIS STORM. THIS COULD CAUSE
PONDING OF WATER ON ROADWAYS...AND MINOR FLOODING OF POOR DRAINAGE
AREAS.
LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS. REMEMBER...IF YOU CAN
HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING. MOVE
TO SAFE SHELTER IMMEDIATELY.
LAT...LON 4124 7411 4132 7399 4133 7391 4129 7376
4100 7392 4110 7414
JCThe Brookhaven radar (KOKX), 73 km away, was scanning. The volume nearest the first event began at 18:53 UTC.
2 flash flood. Local standard time, as filed.
In Naugatuck, the underpass to the Salem Bridge at Rt. 63 was closed due to flooding. There was also at least six inches of flowing water on South Main St. In addition, apartment units on Prospect St., Trowbridge Pl., and Highland Ave. were evacuated due to flooding.
There were numerous road closures and impassable roads throughout Naugatuck due to flooding.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Connecticut in 2012Every state in 2012This day in weather historyWarnings in Connecticut, August 2012
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: 406941, 407317.