Alert archive / New Hampshire / Flash Flood Warnings in 2021

Flash Flood Warning 3, NWS Gray, ME

June 8, 2021Cheshire County, New Hampshire

NWS Gray, ME issued this flash flood warning at Jun 8, 2021, 3:53 PM EDT for Cheshire County, New Hampshire. It was in force for 5 hr. 1 report 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: Jun 8, 2021, 3:53 PM EDT (19:53 UTC)
Expired: Jun 8, 2021, 8:27 PM EDT
In force: 5 hr
Issued by: NWS Gray, ME
Area: Storm-based polygon
Flood severity: None

County Cheshire County, NH

The radar

The Albany radar (KENX), 148 km from the middle of the area, began a volume at 19:56 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
Jun 8, 5:20 PM EDT	FLASH FLOOD	2 Se Keene, NH	FLOODING/ROAD CLOSURE AT ROXBURY AND DOVER ST.

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

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 7.9 hours before the alert went out and 126 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: 289 J/kg
Mixed-layer CIN: -113 J/kg
Mixed-layer LCL: 1170 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 40 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

712 
WGUS51 KGYX 081953
FFWGYX
NHC005-090045-
/O.NEW.KGYX.FF.W.0003.210608T1953Z-210609T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Gray ME
353 PM EDT Tue Jun 8 2021

The National Weather Service in Gray has issued a

* Flash Flood Warning for...
  Cheshire County in southern New Hampshire...

* Until 845 PM EDT.

* At 353 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 2 inches of rain have fallen. Additional rainfall amounts of 
  2 to 3 inches are possible in the warned area. Flash flooding is 
  ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Keene, Jaffrey, Swanzey, Rindge, Winchester, Marlborough, 
  Fitzwilliam, Hancock, Dublin, and Richmond.

This includes the following Rec locations...
	Mount Monadnock.

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 4312 7243 4313 7218 4313 7203 4302 7206
      4294 7206 4294 7201 4279 7198 4279 7222
      4282 7255 4288 7256 4292 7252 4295 7253
      4297 7247 4300 7246 4301 7244 4303 7246
      4305 7247 4308 7244 4310 7244

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

MEC

2 follow-up statements

495 
WGUS71 KGYX 082245
FFSGYX

Flash Flood Statement
National Weather Service Gray ME
645 PM EDT Tue Jun 8 2021

NHC005-090045-
/O.CON.KGYX.FF.W.0003.000000T0000Z-210609T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cheshire NH-
645 PM EDT Tue Jun 8 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM EDT THIS 
EVENING FOR CHESHIRE COUNTY...

At 645 PM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 
1.5 and 2.5 inches of rain have fallen. Additional rainfall amounts 
of 1 to 2 inches are possible in the warned area. Flash flooding is 
ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar and automated gauges.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Keene, Jaffrey, Swanzey, Rindge, Winchester, Marlborough, 
  Fitzwilliam, Hancock, Dublin, and Richmond.

This includes the following Rec locations...
	Mount Monadnock.

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 4312 7243 4313 7218 4313 7203 4302 7206
      4294 7206 4294 7201 4279 7198 4279 7222
      4282 7255 4288 7256 4292 7252 4295 7253
      4297 7247 4300 7246 4301 7244 4303 7246
      4305 7247 4308 7244 4310 7244

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Tubbs

482 
WGUS71 KGYX 090027
FFSGYX

Flash Flood Statement
National Weather Service Gray ME
827 PM EDT Tue Jun 8 2021

NHC005-090037-
/O.CAN.KGYX.FF.W.0003.000000T0000Z-210609T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cheshire NH-
827 PM EDT Tue Jun 8 2021

...FLASH FLOOD WARNING IS CANCELLED FOR CHESHIRE COUNTY...

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

A Flash Flood Watch remains in effect until 1000 PM EDT for Portions 
of southern New Hampshire.

LAT...LON 4312 7243 4313 7218 4313 7203 4302 7206
      4294 7206 4294 7201 4279 7198 4279 7222
      4282 7255 4288 7256 4292 7252 4295 7253
      4297 7247 4300 7246 4301 7244 4303 7246
      4305 7247 4308 7244 4310 7244

$$

Tubbs

The office that day

Everything else NWS Gray, ME issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 8, 3:14 PM EDT	Flash Flood Warning	GYX	Cheshire, Hillsborough	2 hr
Jun 8, 3:24 PM EDT	Flash Flood Watch	GYX	Cheshire, Hillsborough	6 hr
Jun 8, 3:30 PM EDT	Flash Flood Warning	GYX	Hillsborough	2 hr
Jun 8, 4:52 PM EDT	Special Weather Statement	GYX	Strafford	38 min
Jun 8, 4:53 PM EDT	Special Weather Statement	GYX	Cheshire	37 min
Jun 8, 4:56 PM EDT	Special Weather Statement	GYX	Merrimack	34 min
Jun 8, 5:15 PM EDT	Special Weather Statement	GYX	Cheshire	45 min
Jun 8, 5:50 PM EDT	Areal Flood Advisory	GYX	Hillsborough	3 hr
Jun 8, 6:24 PM EDT	Areal Flood Advisory	GYX	Merrimack, Rockingham, Strafford	115 min

Nearby

Flash Flood Warnings in New Hampshire, 2021 Every flash flood warning in 2021

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.