Alert archive / New York / Flash Flood Warnings in 2018

Flash Flood Warning 7, NWS Buffalo, NY

July 4, 2018Allegany County, New York

NWS Buffalo, NY issued this flash flood warning at Jul 4, 2018, 8:18 AM EDT for Allegany County, New York. It was in force for 3 hr. 6 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
Jul 4, 2018, 8:18 AM EDT (12:18 UTC)
Expired
Jul 4, 2018, 11:15 AM EDT
In force
3 hr
Issued by
NWS Buffalo, NY
Area
Storm-based polygon
Flood severity
None

County Allegany County, NY

The radar

The Buffalo radar (KBUF), 105 km from the middle of the area, began a volume at 12:18 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
Jul 4, 8:27 AM EDTFLASH FLOODRichburg, NYSOCIAL MEDIA VIDEO OF WATER FLOWING OVER ROAD NEAR SUNNY HILL AND RICHBURG.
Jul 4, 8:30 AM EDTFLASH FLOODRichburg, NYWATER AND ASSOCIATED DEBRIS OVER ROADS IN BOLIVAR...CLARKSVILLE AND RICHBURG. TIME ESTIMATED.
Jul 4, 8:45 AM EDTFLASH FLOODWest Clarksville, NYROUTE 40 IN THE TOWN OF CLARKSVILLE CLOSED DUE TO WATER AND ASSOCIATED DEBRIS OVER THE ROAD. TIME ESTIMATED.
Jul 4, 9:00 AM EDTFLASH FLOOD4 S Belfast, NYROUTE 41 IN THE TOWN OF BELFAST CLOSED DUE TO WATER AND ASSOCIATED DEBRIS OVER ROAD. TIME ESTIMATED.
Jul 4, 9:00 AM EDTFLASH FLOOD5 S Stannards, NYRT 19 IN SHONGO CLOSED DUE TO WATER AND ASSOCIATED DEBRIS OVER ROAD. TIME ESTIMATED.
Jul 4, 9:09 AM EDTFLASH FLOODBolivar, NYSOCIAL MEDIA VIDEO OF WATER OVER REED ST IN BOLIVAR

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

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 0.3 hours before the alert went out and 102 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, Buffalo Intl Airport, NY at 12:00Z on 2018-07-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 466 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, Buffalo Intl Airport, NY at 12:00Z on 2018-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.1939Sfc1 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
466 J/kg
Mixed-layer CIN
-91 J/kg
Mixed-layer LCL
1219 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
26 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

570 
WGUS51 KBUF 041218
FFWBUF
NYC003-041515-
/O.NEW.KBUF.FF.W.0007.180704T1218Z-180704T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Buffalo NY
818 AM EDT WED JUL 4 2018

The National Weather Service in Buffalo has issued a

* Flash Flood Warning for...
  Allegany County in western New York...

* Until 1115 AM EDT.

* At 818 AM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have
  already fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Wellsville, Alfred, Cuba, Whitesville, Friendship, Scio, Bolivar
  and Andover.

This includes Interstate 86 between exits 28 and 32.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4200 7830 4235 7831 4232 7774 4200 7775

$$

Smith
3 follow-up statements
582 
WGUS71 KBUF 041334
FFSBUF

Flash Flood Statement
National Weather Service Buffalo NY
934 AM EDT WED JUL 4 2018

NYC003-041515-
/O.CON.KBUF.FF.W.0007.000000T0000Z-180704T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegany NY-
934 AM EDT WED JUL 4 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 AM EDT FOR
ALLEGANY COUNTY...

At 932 AM EDT, local law enforcement reported flash flooding in 
Bolivar, Richburg and Clarksville. Up to two inches of rain have 
already fallen. Flash flooding is already occurring and will 
continue to threaten the warned area this morning as additional 
storms develop.

Some locations that will experience flooding include...
Wellsville, Alfred, Cuba, Whitesville, Friendship, Scio, Bolivar and
Andover.

This includes Interstate 86 between exits 28 and 32.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4200 7830 4235 7831 4232 7774 4200 7775

$$

Smith
898 
WGUS71 KBUF 041425
FFSBUF

Flash Flood Statement
National Weather Service Buffalo NY
1025 AM EDT WED JUL 4 2018

NYC003-041515-
/O.CON.KBUF.FF.W.0007.000000T0000Z-180704T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegany NY-
1025 AM EDT WED JUL 4 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 AM EDT FOR
SOUTHWESTERN ALLEGANY COUNTY...

At 1021 AM EDT, local law enforcement reported flash flooding in 
Bolivar, Richburg and Clarksville earlier this morning. Up to two 
inches of rain have already fallen. Flash flooding continues to 
remain a threat as runoff from heavy rain works through the basins.

Some locations that will experience flooding include...
Bolivar, Alma, Richburg, West Clarksville, Little Genesee and Ceres. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4200 7830 4221 7830 4212 7805 4200 7805

$$

Smith
891 
WGUS71 KBUF 041514
FFSBUF

Flash Flood Statement
National Weather Service Buffalo NY
1114 AM EDT WED JUL 4 2018

NYC003-041523-
/O.EXP.KBUF.FF.W.0007.000000T0000Z-180704T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegany NY-
1114 AM EDT WED JUL 4 2018

...THE FLASH FLOOD WARNING FOR SOUTHWESTERN ALLEGANY COUNTY WILL
EXPIRE AT 1115 AM EDT...

The heavy rain has ended. Flash flooding is no longer expected to 
pose a threat. Please continue to heed any remaining road closures.

LAT...LON 4200 7830 4221 7830 4212 7805 4200 7805

$$

Smith

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 4, 7:40 AM EDTSpecial Weather StatementBUFAllegany35 min
Jul 4, 9:12 AM EDTFlash Flood WarningBUFCattaraugus3 hr
Jul 4, 2:44 PM EDTHeat AdvisoryBUFCayuga, Erie, Genesee, Jefferson, Lewis, Livingston and 6 more29 hr
Jul 4, 5:34 PM EDTSpecial Weather StatementBUFErie41 min
Jul 4, 5:38 PM EDTSevere Thunderstorm WarningBUFCattaraugus, Erie47 min

Nearby

Flash Flood Warnings in New York, 2018Every flash flood warning in 2018

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.