Alert archive / Massachusetts / Flash Flood Warnings in 2023

Flash Flood Warning 21, NWS Boston/Norton, MA

July 13, 2023Franklin County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Jul 13, 2023, 9:35 PM EDT for Franklin County, Massachusetts. It was in force for 101 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: Jul 13, 2023, 9:35 PM EDT (01:35 UTC)
Expired: Jul 13, 2023, 11:16 PM EDT
In force: 101 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Flood severity: None

County Franklin County, MA

The radar

The Albany radar (KENX), 127 km from the middle of the area, began a volume at 01:37 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

Brookhaven, NY (KOKX), launched 00:00Z, 1.6 hours before the alert went out and 184 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: 1347 J/kg
Mixed-layer CIN: -64 J/kg
Mixed-layer LCL: 910 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 202 m²/s²
0-3 km storm-relative helicity: 222 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 11.4

Open this sounding in Storm Lab

The text

As transmitted.

164 
WGUS51 KBOX 140135
FFWBOX
MAC011-140445-
/O.NEW.KBOX.FF.W.0021.230714T0135Z-230714T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
935 PM EDT Thu Jul 13 2023

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Northeastern Franklin County in western Massachusetts...

* Until 1245 AM EDT.

* At 935 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 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.

  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...
  Amherst, Greenfield, Orange, Deerfield, Montague, Hadley, 
  Sunderland, Hatfield, Northfield, Bernardston, Conway, Shelburne, 
  Leverett, Erving, Shutesbury, Colrain, Gill, Whately, Pelham and 
  Royalston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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

&&

LAT...LON 4241 7269 4273 7269 4272 7228 4242 7231
      4241 7249 4243 7249

FLASH FLOOD...RADAR INDICATED

$$

KS

1 follow-up statement

662 
WGUS71 KBOX 140316
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
1116 PM EDT Thu Jul 13 2023

MAC011-140326-
/O.CAN.KBOX.FF.W.0021.000000T0000Z-230714T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Franklin MA-
1116 PM EDT Thu Jul 13 2023

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN FRANKLIN 
COUNTY...

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 600 AM EDT Friday for portions 
of northern Connecticut. Portions of western Massachusetts.

A Flood Watch remains in effect until 600 AM EDT Friday for portions 
of northern Connecticut. Portions of Massachusetts. Portions of 
Rhode Island.

LAT...LON 4241 7269 4273 7269 4272 7228 4242 7231
      4241 7249 4243 7249

$$

KS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 13, 8:08 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire	67 min
Jul 13, 9:03 PM EDT	Flash Flood Warning	BOX	Franklin, Hampshire	2 hr
Jul 13, 9:08 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire, Worcester	67 min
Jul 13, 9:15 PM EDT	Severe Thunderstorm Warning	BOX	Hampden, Hampshire	60 min
Jul 13, 9:44 PM EDT	Special Weather Statement	BOX	Worcester	31 min
Jul 13, 9:59 PM EDT	Special Weather Statement	BOX	Middlesex	61 min
Jul 13, 10:08 PM EDT	Special Weather Statement	BOX	Hampden, Worcester	67 min
Jul 14, 6:14 AM EDT	Special Marine Warning	BOX		42 min
Jul 14, 8:05 AM EDT	Special Marine Warning	BOX		36 min
Jul 14, 8:11 AM EDT	Special Weather Statement	BOX	Nantucket	49 min
Jul 14, 9:41 AM EDT	Special Marine Warning	BOX		64 min
Jul 14, 10:16 AM EDT	Special Weather Statement	BOX	Worcester	59 min
Jul 14, 10:31 AM EDT	Special Weather Statement	BOX	Franklin, Hampden, Hampshire	59 min
Jul 14, 11:21 AM EDT	Special Weather Statement	BOX	Middlesex, Worcester	39 min
Jul 14, 11:50 AM EDT	Areal Flood Warning	BOX	Franklin, Hampden, Hampshire, Middlesex, Worcester	2 hr
Jul 14, 12:34 PM EDT	Areal Flood Warning	BOX	Essex, Middlesex, Worcester	3 hr

Nearby

Flash Flood Warnings in Massachusetts, 2023 Every flash flood warning in 2023

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.