Alert archive / New Hampshire / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Gray, ME

June 8, 2021Cheshire County, Hillsborough County, New Hampshire

NWS Gray, ME issued this flash flood warning at Jun 8, 2021, 3:14 PM EDT for Cheshire County, Hillsborough County, New Hampshire. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 8, 2021, 3:14 PM EDT (19:14 UTC)
Expired
Jun 8, 2021, 5:27 PM EDT
In force
2 hr
Issued by
NWS Gray, ME
Area
Storm-based polygon
Flood severity
None

Counties Cheshire County, NH, Hillsborough County, NH

The radar

The Boston radar (KBOX), 111 km from the middle of the area, began a volume at 19:18 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.

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 7.2 hours before the alert went out and 157 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, Albany, NY at 12:00Z on 2021-06-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 289 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, Albany, NY at 12:00Z on 2021-06-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
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.

709 
WGUS51 KGYX 081914
FFWGYX
NHC005-011-082215-
/O.NEW.KGYX.FF.W.0001.210608T1914Z-210608T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Gray has issued a

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

* Until 615 PM EDT.

* At 314 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 1.5 inches of rain have fallen. The expected rainfall rate 
  is 2 to 4 inches in the next 2 hours. 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...
  Jaffrey, Milford, Rindge, Fitzwilliam, Mason, New Ipswich, Temple, 
  Greenville, Sharon, and Wilton.

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 4280 7211 4282 7179 4281 7165 4271 7167
      4272 7211

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...2-4 INCHES IN 2 HOURS

$$

MEC
1 follow-up statement
149 
WGUS71 KGYX 082127
FFSGYX

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

NHC005-011-082137-
/O.CAN.KGYX.FF.W.0001.000000T0000Z-210608T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cheshire NH-Hillsborough NH-
527 PM EDT Tue Jun 8 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN CHESHIRE AND 
SOUTHWESTERN HILLSBOROUGH COUNTIES...

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 4280 7211 4282 7179 4281 7165 4271 7167
      4272 7211

$$

Tubbs

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 8, 3:24 PM EDTFlash Flood WatchGYXCheshire, Hillsborough6 hr
Jun 8, 3:30 PM EDTFlash Flood WarningGYXHillsborough2 hr
Jun 8, 3:53 PM EDTFlash Flood WarningGYXCheshire5 hr
Jun 8, 4:52 PM EDTSpecial Weather StatementGYXStrafford38 min
Jun 8, 4:53 PM EDTSpecial Weather StatementGYXCheshire37 min
Jun 8, 4:56 PM EDTSpecial Weather StatementGYXMerrimack34 min
Jun 8, 5:15 PM EDTSpecial Weather StatementGYXCheshire45 min
Jun 8, 5:50 PM EDTAreal Flood AdvisoryGYXHillsborough3 hr
Jun 8, 6:24 PM EDTAreal Flood AdvisoryGYXMerrimack, Rockingham, Strafford115 min

Nearby

Flash Flood Warnings in New Hampshire, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.