Alert archive / New York / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 85, NWS Buffalo, NY

August 20, 2009Chautauqua County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at Aug 20, 2009, 7:47 PM EDT for Chautauqua County, New York. It was in force for 73 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 20, 2009, 7:47 PM EDT (23:47 UTC)
Expired: Aug 20, 2009, 9:00 PM EDT
In force: 73 min
Issued by: NWS Buffalo, NY
Area: Storm-based polygon

County Chautauqua County, NY

The radar

The Buffalo radar (KBUF), 91 km from the middle of the area, began a volume at 23:46 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

Time	Report	Where	Remark
Aug 20, 8:55 PM EDT	TSTM WND DMG	Jamestown, NY	LINES DOWN
Aug 20, 9:05 PM EDT	TSTM WND DMG	Frewsburg, NY	TREES DOWN

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.

Issued	Product	Office	Lasted
Aug 20, 6:54 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 11.8 hours before the alert went out and 91 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1149 J/kg
Mixed-layer CIN: -36 J/kg
Mixed-layer LCL: 810 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 94 m²/s²
0-3 km storm-relative helicity: 110 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 2.2

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KBUF 202347
SVRBUF
NYC013-210100-
/O.NEW.KBUF.SV.W.0085.090820T2347Z-090821T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BUFFALO NY
747 PM EDT THU AUG 20 2009

THE NATIONAL WEATHER SERVICE IN BUFFALO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CHAUTAUQUA COUNTY IN WESTERN NEW YORK

* UNTIL 900 PM EDT

* AT 743 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM 21 MILES WEST OF FINDLEY LAKE TO 25 MILES WEST OF             
  CLYMER...AND MOVING EAST AT 40 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  FINDLEY LAKE BY 815 PM EDT...
  CLYMER BY 820 PM EDT...
  WESTFIELD AND MAYVILLE BY 830 PM EDT...
  CHAUTAUQUA INSTITUTE BY 835 PM EDT...
  LAKEWOOD BY 845 PM EDT...
  FREDONIA...DUNKIRK AND JAMESTOWN BY 850 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE STORMS HAVE A HISTORY OF PRODUCING WIND DAMAGE ACROSS  
NORTHWEST PA.  SEEK SHELTER NOW

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT 
TONIGHT FOR WESTERN NEW YORK.

&&

LAT...LON 4226 7977 4228 7975 4231 7966 4242 7945
      4250 7936 4251 7932 4256 7920 4258 7915
      4254 7905 4200 7906 4199 7961 4200 7977
TIME...MOT...LOC 2346Z 256DEG 34KT 4216 8009 4190 8006

$$

ZAFF

2 follow-up statements

000 
WWUS51 KBUF 210023
SVSBUF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
823 PM EDT THU AUG 20 2009

NYC013-210100-
/O.CON.KBUF.SV.W.0085.000000T0000Z-090821T0100Z/
CHAUTAUQUA NY-
823 PM EDT THU AUG 20 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR CHAUTAUQUA COUNTY...

AT 819 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE 
EXTENDING FROM RIPLEY TO CLYMER...MOVING EAST AT 40 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  CHAUTAUQUA INSTITUTE BY 830 PM EDT...
  BROCTON BY 840 PM EDT...
  CASSADAGA BY 845 PM EDT...
  FREDONIA BY 850 PM EDT...
  ARKWRIGHT BY 855 PM EDT...
  ELLINGTON BY 900 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE STORMS HAVE A HISTORY OF PRODUCING WIND DAMAGE ACROSS 
NORTHWEST PENNSYLVANIA. REMEMBER...SEVERE THUNDERSTORMS CAN AND DO 
PRODUCE TORNADOES. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND 
STAY AWAY FROM WINDOWS 

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 200 AM EDT FRIDAY
MORNING FOR WESTERN NEW YORK.

&&

LAT...LON 4226 7977 4228 7975 4231 7966 4242 7945
      4250 7936 4251 7932 4256 7920 4258 7915
      4254 7905 4200 7906 4199 7961 4200 7977
TIME...MOT...LOC 0022Z 256DEG 34KT 4228 7962 4202 7959

$$

HITCHCOCK

000 
WWUS51 KBUF 210047
SVSBUF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
847 PM EDT THU AUG 20 2009

NYC013-210100-
/O.CON.KBUF.SV.W.0085.000000T0000Z-090821T0100Z/
CHAUTAUQUA NY-
847 PM EDT THU AUG 20 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR EASTERN CHAUTAUQUA COUNTY...

AT 846 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE 
EXTENDING FROM DUNKIRK TO 4 MILES WEST OF JAMESTOWN...MOVING 
NORTHEAST AT 45 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  SILVER CREEK AND FREWSBURG AND FORESTVILLE BY 855 PM EDT...
  ELLINGTON AND CHERRY CREEK BY 900 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THESE STORMS. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT 
TONIGHT FOR WESTERN NEW YORK.

&&

LAT...LON 4200 7943 4237 7941 4250 7936 4258 7915
      4254 7905 4253 7905 4253 7906 4237 7905
      4200 7906
TIME...MOT...LOC 0047Z 243DEG 39KT 4248 7927 4203 7928

$$

HITCHCOCK

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 6:31 PM EDT	Special Marine Warning	BUF		119 min
Aug 20, 7:15 PM EDT	Special Marine Warning	BUF		2 hr
Aug 20, 7:56 PM EDT	Severe Thunderstorm Warning	BUF	Erie, Niagara	79 min

Nearby

Severe Thunderstorm Warnings in New York, 2009 Every severe thunderstorm warning in 2009

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.