Alert archive / New York / Tornado Warnings in 2011

Tornado Warning 6, NWS New York, NY

August 21, 2011Putnam County, Westchester County, New York

NWS New York, NY issued this tornado warning at Aug 21, 2011, 4:37 PM EDT for Putnam County, Westchester County, New York. It was in force for 38 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 21, 2011, 4:37 PM EDT (20:37 UTC)
Expired
Aug 21, 2011, 5:15 PM EDT
In force
38 min
Issued by
NWS New York, NY
Area
Storm-based polygon

Counties Putnam County, NY, Westchester County, NY

The radar

The Brookhaven radar (KOKX), 89 km from the middle of the area, began a volume at 20:39 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Aug 21, 4:45 PM EDTTSTM WND DMGSomers, NYTREES DOWN IN SOMERS REPORTED BY STATE POLICE
Aug 21, 5:05 PM EDTTSTM WND DMGNorth Salem, NYSTATE POLICE REPORTING TREES DOWN IN NORTH SALEM.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 21, 12:52 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 8.6 hours before the alert went out and 89 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2011-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 874 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2011-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 55 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
874 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
857 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
55 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

090 
WFUS51 KOKX 212037
TOROKX
NYC079-119-212115-
/O.NEW.KOKX.TO.W.0006.110821T2037Z-110821T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
437 PM EDT SUN AUG 21 2011

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS ISSUED A

* TORNADO WARNING FOR...
  WESTCHESTER COUNTY IN SOUTHEAST NEW YORK...
  PUTNAM COUNTY IN SOUTHEAST NEW YORK...

* UNTIL 515 PM EDT...

* AT 435 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR YORKTOWN
  HEIGHTS...OR NEAR MAHOPAC...MOVING EAST AT 15 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  CARMEL...LAKE CARMEL AND BREWSTER

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WHEN A TORNADO WARNING IS ISSUED BASED ON DOPPLER RADAR...IT MEANS
THAT STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY
ALREADY BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY. IF YOU
ARE IN THE PATH OF THIS DANGEROUS STORM...MOVE INDOORS AND TO THE
LOWEST LEVEL OF THE BUILDING. STAY AWAY FROM WINDOWS. IF DRIVING...DO
NOT SEEK SHELTER UNDER A HIGHWAY OVERPASS.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM SUNDAY
EVENING FOR SOUTHERN CONNECTICUT AND NORTHEAST NEW JERSEY AND
SOUTHEAST NEW YORK.

&&

LAT...LON 4153 7364 4146 7353 4132 7355 4120 7373
      4133 7390
TIME...MOT...LOC 2037Z 253DEG 14KT 4130 7375

$$

BC
1 follow-up statement
744 
WWUS51 KOKX 212101
SVSOKX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
501 PM EDT SUN AUG 21 2011

NYC079-119-212115-
/O.CON.KOKX.TO.W.0006.000000T0000Z-110821T2115Z/
PUTNAM NY-WESTCHESTER NY-
501 PM EDT SUN AUG 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM EDT FOR NORTHERN
WESTCHESTER AND PUTNAM COUNTIES...

AT 456 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO.  THIS TORNADO WAS LOCATED NEAR GOLDEN'S BRIDGE...
OR NEAR MAHOPAC...MOVING EAST AT 15 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
BREWSTER...BREWSTER HILL AND PEACH LAKE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM SUNDAY
EVENING FOR SOUTHERN CONNECTICUT AND NORTHEAST NEW JERSEY AND
SOUTHEAST NEW YORK.

&&

LAT...LON 4146 7354 4141 7354 4132 7355 4125 7365
      4134 7377 4149 7361
TIME...MOT...LOC 2101Z 253DEG 14KT 4133 7363

$$

BC

The office that day

Everything else NWS New York, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 3:49 AM EDTSmall Craft AdvisoryOKX30 hr
Aug 21, 6:00 AM EDTFlash Flood WatchOKXBronx, Kings, Nassau, New York, Orange, Putnam and 4 more15 hr
Aug 21, 11:32 AM EDTSpecial Weather StatementOKXBronx, New York43 min
Aug 21, 12:13 PM EDTSpecial Weather StatementOKXBronx47 min
Aug 21, 12:26 PM EDTSevere Thunderstorm WarningOKXWestchester49 min
Aug 21, 12:51 PM EDTSpecial Weather StatementOKXOrange54 min
Aug 21, 12:59 PM EDTSevere Thunderstorm WarningOKXPutnam23 min
Aug 21, 1:09 PM EDTSevere Thunderstorm WarningOKXWestchester21 min
Aug 21, 1:17 PM EDTSpecial Weather StatementOKXRockland58 min
Aug 21, 1:23 PM EDTSpecial Weather StatementOKXPutnam67 min
Aug 21, 1:28 PM EDTSpecial Weather StatementOKXOrange62 min
Aug 21, 1:43 PM EDTSevere Thunderstorm WarningOKXPutnam, Rockland, Westchester47 min
Aug 21, 2:15 PM EDTSevere Thunderstorm WarningOKXPutnam21 min
Aug 21, 3:43 PM EDTSpecial Marine WarningOKX32 min
Aug 21, 4:00 PM EDTSevere Thunderstorm WarningOKXPutnam, Westchester45 min
Aug 21, 4:07 PM EDTSevere Thunderstorm WarningOKXKings, Nassau, Queens38 min
Aug 21, 4:20 PM EDTSpecial Marine WarningOKX40 min
Aug 21, 4:47 PM EDTSevere Thunderstorm WarningOKXNassau, Queens, Suffolk17 min
Aug 21, 4:58 PM EDTTornado WarningOKXPutnam30 min
Aug 21, 5:51 PM EDTSpecial Weather StatementOKXRockland, Westchester39 min
Aug 21, 6:33 PM EDTAreal Flood AdvisoryOKXOrange, Rockland117 min
Aug 21, 6:38 PM EDTSpecial Weather StatementOKXRockland52 min
Aug 21, 6:46 PM EDTFlash Flood WarningOKXOrange, Rockland56 min
Aug 21, 7:19 PM EDTSpecial Weather StatementOKXPutnam41 min
Aug 21, 7:25 PM EDTAreal Flood AdvisoryOKXPutnam, Westchester2 hr

Nearby

Tornado Warnings in New York, 2011Every tornado warning in 2011Tornadoes in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.