Alert archive / Massachusetts / Flash Flood Warnings in 2014

Flash Flood Warning 20, NWS Boston/Norton, MA

July 15, 2014Essex County, Middlesex County, Worcester County, Massachusetts; Hillsborough County, New Hampshire

NWS Boston/Norton, MA issued this flash flood warning at Jul 15, 2014, 4:31 PM EDT for Essex County, Middlesex County, Worcester County, Massachusetts; Hillsborough County, New Hampshire. It was in force for 119 min. 2 reports 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: Jul 15, 2014, 4:31 PM EDT (20:31 UTC)
Expired: Jul 15, 2014, 6:30 PM EDT
In force: 119 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Flood severity: None

Counties Essex County, MA, Middlesex County, MA, Worcester County, MA, Hillsborough County, NH

The radar

The Boston radar (KBOX), 87 km from the middle of the area, began a volume at 20:31 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
Jul 15, 4:35 PM EDT	FLASH FLOOD	Billerica, MA	MBCR BRIDGE ON PLEASANT STREET CLOSED DUE TO FLOODING. STILL 6 INCHES OF STANDING WATER AT 527 PM.
Jul 15, 5:06 PM EDT	FLASH FLOOD	South Lowell, MA	PORTION OF BILLERICA ST FLOODED AND IMPASSABLE

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

The nearest sounding before it

Gray, ME (KGYX), launched 12:00Z, 8.5 hours before the alert went out and 149 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: 318 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 492 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 76 m²/s²
0-3 km storm-relative helicity: 193 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

857 
WGUS51 KBOX 152031
FFWBOX
MAC009-017-027-NHC011-152230-
/O.NEW.KBOX.FF.W.0020.140715T2031Z-140715T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
431 PM EDT TUE JUL 15 2014

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  NORTHEASTERN MIDDLESEX COUNTY IN NORTHEAST MASSACHUSETTS...
  NORTHWESTERN ESSEX COUNTY IN NORTHEAST MASSACHUSETTS...
  SOUTHEASTERN HILLSBOROUGH COUNTY IN SOUTHERN NEW HAMPSHIRE...

* UNTIL 630 PM EDT

* AT 430 PM EDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING 
  TORRENTIAL DOWNPOURS IN THE MERRIMACK VALLEY. RAINFALL RATES AS 
  HIGH AS 2 TO 3 INCHES PER HOUR WILL CAUSE RAPID FLOODING OF URBAN 
  AREAS.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  LOWELL...NASHUA...LAWRENCE...HAVERHILL...METHUEN...BILLERICA...
  CHELMSFORD...ANDOVER...DRACUT...TEWKSBURY...NORTH ANDOVER...
  HUDSON...WILMINGTON...WESTFORD...ACTON...CONCORD...SUDBURY...
  NEWBURYPORT...HOLDEN...AMESBURY...CLINTON...BEDFORD...PELHAM...
  TYNGSBOROUGH...GROTON...MAYNARD...LITTLETON...SALISBURY...
  GEORGETOWN AND LANCASTER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

RAPID AND POTENTIALLY LIFE THREATENING FLOODING OF STREETS AND
UNDERPASSES IS IMMINENT. DO NOT DRIVE THROUGH FLOODED ROADS AND FIND
ALTERNATE ROUTES.

&&

LAT...LON 4286 7088 4243 7134 4232 7189 4280 7137
      4277 7135 4276 7127 4274 7124 4274 7119
      4280 7118 4281 7116 4282 7112 4281 7107
      4284 7105

$$

JWD

2 follow-up statements

776 
WGUS71 KBOX 152056
FFSBOX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
456 PM EDT TUE JUL 15 2014

MAC009-017-027-NHC011-152230-
/O.CON.KBOX.FF.W.0020.000000T0000Z-140715T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WORCESTER MA-MIDDLESEX MA-ESSEX MA-HILLSBOROUGH NH-
456 PM EDT TUE JUL 15 2014

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM EDT FOR
EAST CENTRAL WORCESTER...NORTHEASTERN MIDDLESEX...NORTHWESTERN ESSEX
AND SOUTHEASTERN HILLSBOROUGH COUNTIES...

AT 454 PM EDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING 
TORRENTIAL DOWNPOURS FROM LAWRENCE TO CLINTON...MOVING NORTHEAST AT 
35 MPH.

RAINFALL RATES AS HIGH AS 2 TO 3 INCHES PER HOUR WILL CAUSE RAPID 
FLOODING OF URBAN AREAS...INCLUDING ROADS AND UNDERPASSES. DRIVERS 
SHOULD BE PREPARED FOR LOW VISIBILITY AND SLOW DOWN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

RAPID AND POTENTIALLY LIFE THREATENING FLOODING OF STREETS AND
UNDERPASSES IS IMMINENT. DO NOT DRIVE THROUGH FLOODED ROADS AND FIND
ALTERNATE ROUTES.

&&

LAT...LON 4286 7088 4243 7134 4232 7189 4280 7137
      4277 7135 4276 7127 4274 7124 4274 7119
      4280 7118 4281 7116 4282 7112 4281 7107
      4284 7105

$$

JWD

624 
WGUS71 KBOX 152144
FFSBOX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
544 PM EDT TUE JUL 15 2014

MAC009-017-027-NHC011-152154-
/O.CAN.KBOX.FF.W.0020.000000T0000Z-140715T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WORCESTER MA-MIDDLESEX MA-ESSEX MA-HILLSBOROUGH NH-
544 PM EDT TUE JUL 15 2014

...THE FLASH FLOOD WARNING FOR EAST CENTRAL WORCESTER...NORTHEASTERN
MIDDLESEX...NORTHWESTERN ESSEX AND SOUTHEASTERN HILLSBOROUGH COUNTIES
IS CANCELLED...

THE HEAVY RAIN HAS ENDED...AND FLOODING IS NO LONGER EXPECTED TO POSE
A THREAT. THEREFORE THE FLASH FLOOD WARNING HAS BEEN CANCELLED.

&&

LAT...LON 4286 7088 4243 7134 4232 7189 4280 7137
      4277 7135 4276 7127 4274 7124 4274 7119
      4280 7118 4281 7116 4282 7112 4281 7107
      4284 7105

$$

JWD

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 15, 2:08 PM EDT	Special Weather Statement	BOX	Hampden	22 min
Jul 15, 2:23 PM EDT	Special Weather Statement	BOX	Worcester	22 min
Jul 15, 2:37 PM EDT	Flash Flood Warning	BOX	Franklin, Hampden, Hampshire, Worcester	113 min
Jul 15, 2:41 PM EDT	Special Weather Statement	BOX	Hampden	34 min
Jul 15, 2:53 PM EDT	Special Weather Statement	BOX	Worcester	37 min
Jul 15, 3:25 PM EDT	Special Weather Statement	BOX	Worcester	50 min
Jul 15, 4:01 PM EDT	Special Weather Statement	BOX	Middlesex	29 min
Jul 15, 4:04 PM EDT	Tornado Warning	BOX	Middlesex	22 min
Jul 15, 4:19 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex	41 min
Jul 15, 4:30 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Worcester	34 min
Jul 15, 4:41 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex	21 min
Jul 15, 4:45 PM EDT	Special Marine Warning	BOX		90 min
Jul 15, 4:59 PM EDT	Severe Thunderstorm Warning	BOX	Essex, Middlesex	46 min
Jul 15, 2:45 PM EDT	Special Weather Statement	BOX	Cheshire	30 min

Nearby

Flash Flood Warnings in Massachusetts, 2014 Flash Flood Warnings in New Hampshire, 2014 Every flash flood warning in 2014

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.