Alert archive / Massachusetts / Flash Flood Warnings in 2003

Flash Flood Warning 4, NWS Boston/Norton, MA

August 7, 2003Middlesex County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Aug 7, 2003, 4:41 PM EDT for Middlesex County, Massachusetts. 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 counties it named.

The facts

Issued: Aug 7, 2003, 4:41 PM EDT (20:41 UTC)
Expired: Aug 7, 2003, 6:45 PM EDT
In force: 2 hr
Issued by: NWS Boston/Norton, MA
Area: Whole counties

County Middlesex County, MA

The radar

The Boston radar (KBOX), 63 km from the middle of the area, began a volume at 20:42 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

Chatham, MA (KCHH), launched 12:00Z, 8.7 hours before the alert went out and 148 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: 56 J/kg
Mixed-layer CIN: -156 J/kg
Mixed-layer LCL: 796 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 65 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KBOX 072042
FFWBOX
MAC017-072245-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
441 PM EDT THU AUG 7 2003

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL MIDDLESEX COUNTY IN EASTERN MASSACHUSETTS
    INCLUDING LOWELL

* UNTIL 645 PM EDT.

* AT 436 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
THUNDERSTORMS WITH TORRENTIAL RAINFALL FROM LITTLETON TO 
LOWELL...MOVING NORTHEAST AT 15 MPH.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.

MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER ATTEMPT TO CROSS
BRIDGES OR ROADS WHERE WATER COVERS THE ROADWAY. IT ONLY TAKES A FOOT
OR TWO OF WATER TO WASH MOST CARS AWAY.

$$

LAT...LON 4256 7156 4249 7147 4263 7124 4269 7132

BELK
NOCERA

1 follow-up statement

000 
WGUS71 KBOX 072119
FFSBOX
MAC017-072215-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
520 PM EDT THU AUG 7 2003

...A FLASH FLOOD WARNING FOR NORTHWEST MIDDLESEX COUNTY CONTINUES 
UNTIL 645 PM...

TORRENTIAL RAINFALL CONTINUES OVER NORTHWEST MIDDLESEX COUNTY AT 520 
PM...SPECIFICALLY ALONG AND SOUTH OF INTERSTATE 495 FROM JUST EAST 
OF LITTLETOWN EXTENDING NORTHEAST TO WESTFORD...CHELMSFORD TO LOWELL.
RAINFALL RATES UP TO 2.7 INCHES PER HOUR HAVE BEEN OBSERVED IN 
CHELMSFORD AND LOWELL.  VERY HEAVY RAIN WILL CONTINUE TO TRAIN OVER 
THE AREA THROUGH 6 PM. 

MOTORISTS SHOULD EXPECT FLOODING ALONG INTERSTATE 495 FROM WESTFORD 
TO LOWELL THIS EVENING.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.

MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER ATTEMPT TO CROSS
BRIDGES OR ROADS WHERE WATER COVERS THE ROADWAY. IT ONLY TAKES A FOOT
OR TWO OF WATER TO WASH MOST CARS AWAY.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS...BRIDGE UNDERPASSES AND ROADSIDE CULVERTS. NEVER
ATTEMPT TO CROSS BRIDGES OR ROADS WHERE WATER COVERS THE ROADWAY. THE
ROADWAY COULD BE DAMAGED OR WASHED OUT.

$$

NOCERA

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 7, 7:12 PM EDT	Flash Flood Warning	BOX	Franklin, Hampshire	3 hr

Nearby

Flash Flood Warnings in Massachusetts, 2003 Every flash flood warning in 2003

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.