Alert archive / Massachusetts / Flash Flood Warnings in 2021

Flash Flood Warning 24, NWS Boston/Norton, MA

August 22, 2021Hampden County, Hampshire County, Massachusetts; Capitol Planning Region, Connecticut

NWS Boston/Norton, MA issued this flash flood warning at Aug 22, 2021, 1:53 PM EDT for Hampden County, Hampshire County, Massachusetts; Capitol Planning Region, Connecticut. It was in force for 4 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: Aug 22, 2021, 1:53 PM EDT (17:53 UTC)
Expired: Aug 22, 2021, 5:27 PM EDT
In force: 4 hr
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Flood severity: None

Counties Capitol Planning Region, CT, Hampden County, MA, Hampshire County, MA

The radar

The Boston radar (KBOX), 122 km from the middle of the area, began a volume at 17:54 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 22, 2:41 PM EDT	FLOOD	3 Nne West Springfield, MA	FLOODING REPORTED ON ROUTE 5 NEAR LONGMEADOW, PER BRIAN LAPIS.

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, 5.9 hours before the alert went out and 123 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: 197 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 827 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 48 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

810 
WGUS51 KBOX 221753
FFWBOX
CTC003-013-MAC013-015-222145-
/O.NEW.KBOX.FF.W.0024.210822T1753Z-210822T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
153 PM EDT Sun Aug 22 2021

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Northeastern Hartford County in northern Connecticut...
  Northwestern Tolland County in northern Connecticut...
  Southeastern Hampden County in western Massachusetts...
  South Central Hampshire County in western Massachusetts...

* Until 545 PM EDT.

* At 153 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 0.5 and 1 inch of rain 
  has fallen. The expected rainfall rate is 1 to 2 inches in 1 hour. 
  Additional rainfall amounts of 2 to 4 inches are possible in the 
  warned area. Flash flooding is ongoing or expected to begin 
  shortly, with sharp rises on rivers and streams over bankfull, 
  with urban flooding anticipated in the Greater Springfield metro 
  area.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  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...
  Springfield, Chicopee, Enfield, Westfield, Holyoke, Agawam, West 
  Springfield, Ludlow, South Hadley, Easthampton, Longmeadow, 
  Suffield, East Longmeadow, Ellington, Tolland, Wilbraham, Palmer, 
  Stafford, Somers and Granby.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4201 7280 4217 7278 4224 7264 4224 7262
      4220 7244 4207 7224 4191 7222 4192 7252
      4197 7263 4193 7277 4200 7280

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

AL/KS

3 follow-up statements

770 
WGUS71 KBOX 221957
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
357 PM EDT Sun Aug 22 2021

CTC003-013-MAC013-015-222145-
/O.CON.KBOX.FF.W.0024.000000T0000Z-210822T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hartford CT-Tolland CT-Hampden MA-Hampshire MA-
357 PM EDT Sun Aug 22 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM EDT THIS 
AFTERNOON FOR NORTHEASTERN HARTFORD, NORTHWESTERN TOLLAND, 
SOUTHEASTERN HAMPDEN AND SOUTH CENTRAL HAMPSHIRE COUNTIES...

At 357 PM EDT, Doppler radar indicated heavy rain from Tropical 
Storm Henri across the warned area. Broadcast media reported 
flooding on portions of Route 5 in East Longmeadow from excessive 
rainfall. Between 1 and 2.5 inches of rain have fallen. The expected 
rainfall rate is 0.5 to 1 inch in 1 hour. Flash flooding is already 
occurring and as rains continue to fall, new or worsened areas of 
flooding remain possible.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Broadcast media and radar.

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...
  Springfield, Chicopee, Enfield, Westfield, Holyoke, Agawam, West 
  Springfield, Ludlow, South Hadley, Easthampton, Longmeadow, 
  Suffield, East Longmeadow, Ellington, Tolland, Wilbraham, Palmer, 
  Stafford, Somers and Granby.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4201 7280 4217 7278 4224 7264 4224 7262
      4220 7244 4207 7224 4191 7222 4192 7252
      4197 7263 4193 7277 4200 7280

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-1 INCH IN 1 HOUR

$$

AL

628 
WGUS71 KBOX 222055
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
455 PM EDT Sun Aug 22 2021

CTC003-013-MAC013-015-222145-
/O.CON.KBOX.FF.W.0024.000000T0000Z-210822T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hartford CT-Tolland CT-Hampden MA-Hampshire MA-
455 PM EDT Sun Aug 22 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM EDT THIS 
AFTERNOON FOR NORTHEASTERN HARTFORD, NORTHWESTERN TOLLAND, 
SOUTHEASTERN HAMPDEN AND SOUTH CENTRAL HAMPSHIRE COUNTIES...

At 455 PM EDT, rain from Tropical Storm Henri has lightened in 
intensity across the warned area. Broadcast media in Springfield 
reported flooding on portions of Route 5 in East Longmeadow from 
excessive rainfall. In addition, broadcast media in Hartford 
reported flooding on Burke Road in Vernon. Up to 3 inches of rain 
have fallen. Flash flooding is already occurring and new or worsened 
areas of flooding remain possible.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Broadcast media reported.

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...
  Springfield, Chicopee, Enfield, Westfield, Holyoke, Agawam, West 
  Springfield, Ludlow, South Hadley, Easthampton, Longmeadow, 
  Suffield, East Longmeadow, Ellington, Tolland, Wilbraham, Palmer, 
  Stafford, Somers and Granby.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4201 7280 4217 7278 4224 7264 4224 7262
      4220 7244 4207 7224 4191 7222 4192 7252
      4197 7263 4193 7277 4200 7280

FLASH FLOOD...OBSERVED

$$

AL

002 
WGUS71 KBOX 222127
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
527 PM EDT Sun Aug 22 2021

CTC003-013-MAC013-015-222137-
/O.CAN.KBOX.FF.W.0024.000000T0000Z-210822T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hartford CT-Tolland CT-Hampden MA-Hampshire MA-
527 PM EDT Sun Aug 22 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN HARTFORD, 
NORTHWESTERN TOLLAND, SOUTHEASTERN HAMPDEN AND SOUTH CENTRAL 
HAMPSHIRE COUNTIES...

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

A Flood Watch remains in effect until 800 PM EDT Monday for portions 
of northern Connecticut, Massachusetts and Rhode Island.

LAT...LON 4201 7280 4217 7278 4224 7264 4224 7262
      4220 7244 4207 7224 4191 7222 4192 7252
      4197 7263 4193 7277 4200 7280

$$

AL

The office that day

Everything else NWS Boston/Norton, MA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 22, 7:28 AM EDT	Small Craft Advisory	BOX		61 hr
Aug 22, 9:43 AM EDT	Coastal Flood Advisory	BOX	Barnstable, Bristol, Dukes, Essex, Nantucket, Norfolk and 2 more	16 hr
Aug 22, 4:11 PM EDT	Areal Flood Warning	BOX	Franklin, Hampden, Hampshire	4 hr
Aug 22, 1:28 PM EDT	Flash Flood Warning	BOX	Capitol Planning Region, Northeastern Connecticut Planning Region	4 hr
Aug 22, 1:37 PM EDT	Flash Flood Warning	BOX	Capitol Planning Region	4 hr

Nearby

Flash Flood Warnings in Massachusetts, 2021 Flash Flood Warnings in Connecticut, 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.