Alert archive / Massachusetts / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Boston/Norton, MA

June 8, 2021Hampshire County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Jun 8, 2021, 1:02 PM EDT for Hampshire County, Massachusetts. It was in force for 55 min. 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, 1:02 PM EDT (17:02 UTC)
Expired: Jun 8, 2021, 1:57 PM EDT
In force: 55 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Flood severity: None

County Hampshire County, MA

The radar

The Albany radar (KENX), 124 km from the middle of the area, began a volume at 17:02 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, 5.0 hours before the alert went out and 108 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.

926 
WGUS51 KBOX 081702
FFWBOX
MAC015-081900-
/O.NEW.KBOX.FF.W.0001.210608T1702Z-210608T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
102 PM EDT Tue Jun 8 2021

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Central Hampshire County in western Massachusetts...

* Until 300 PM EDT.

* At 102 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Amherst, Northampton, Easthampton, Belchertown, Hadley, Hatfield, 
  Williamsburg, Shutesbury, Whately and Pelham.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4241 7248 4234 7247 4229 7265 4241 7267
      4241 7266 4242 7262 4242 7259 4242 7258
      4243 7248

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2-3 INCHES IN 1 HOUR 

$$

KJC

1 follow-up statement

899 
WGUS71 KBOX 081757
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
157 PM EDT Tue Jun 8 2021

MAC015-081807-
/O.CAN.KBOX.FF.W.0001.000000T0000Z-210608T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hampshire MA-
157 PM EDT Tue Jun 8 2021

...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL HAMPSHIRE 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 Tuesday for 
portions of northern Connecticut and Massachusetts.

LAT...LON 4241 7248 4234 7247 4229 7265 4241 7267
      4241 7266 4242 7262 4242 7259 4242 7258
      4243 7248

$$

KJC

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 8, 12:35 PM EDT	Special Weather Statement	BOX	Hampshire	40 min
Jun 8, 12:54 PM EDT	Flash Flood Watch	BOX	Franklin, Hampden, Hampshire, Middlesex, Worcester	8 hr
Jun 8, 1:13 PM EDT	Special Weather Statement	BOX	Hampden	47 min
Jun 8, 1:34 PM EDT	Severe Thunderstorm Warning	BOX	Hampden, Hampshire	41 min
Jun 8, 1:39 PM EDT	Flash Flood Warning	BOX	Hampden, Hampshire	67 min
Jun 8, 2:40 PM EDT	Special Weather Statement	BOX	Hampshire	50 min
Jun 8, 2:56 PM EDT	Severe Thunderstorm Warning	BOX	Hampden	43 min
Jun 8, 3:09 PM EDT	Special Weather Statement	BOX	Worcester	51 min
Jun 8, 3:12 PM EDT	Special Weather Statement	BOX	Essex	48 min
Jun 8, 3:32 PM EDT	Special Marine Warning	BOX		43 min
Jun 8, 3:37 PM EDT	Special Weather Statement	BOX	Hampshire	38 min
Jun 8, 3:42 PM EDT	Special Weather Statement	BOX	Essex	48 min
Jun 8, 3:51 PM EDT	Special Weather Statement	BOX	Hampshire	39 min
Jun 8, 3:52 PM EDT	Special Marine Warning	BOX		53 min
Jun 8, 4:02 PM EDT	Special Weather Statement	BOX	Norfolk	43 min
Jun 8, 4:04 PM EDT	Special Weather Statement	BOX	Hampshire	41 min
Jun 8, 4:13 PM EDT	Special Weather Statement	BOX	Essex	47 min
Jun 8, 4:38 PM EDT	Special Marine Warning	BOX		52 min
Jun 8, 5:17 PM EDT	Severe Thunderstorm Warning	BOX	Bristol, Middlesex, Norfolk, Worcester	58 min
Jun 8, 5:33 PM EDT	Special Marine Warning	BOX		42 min
Jun 8, 5:59 PM EDT	Severe Thunderstorm Warning	BOX	Bristol, Norfolk, Plymouth, Suffolk	35 min

Nearby

Flash Flood Warnings in Massachusetts, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.