Alert archive / Massachusetts / Flash Flood Warnings in 2016

Flash Flood Warning 7, NWS Boston/Norton, MA

October 21, 2016Middlesex County, Norfolk County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Oct 21, 2016, 8:28 PM EDT for Middlesex County, Norfolk County, Worcester County, Massachusetts. It was in force for 2 hr. 15 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: Oct 21, 2016, 8:28 PM EDT (00:28 UTC)
Expired: Oct 21, 2016, 10:30 PM EDT
In force: 2 hr
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Flood severity: None

Counties Middlesex County, MA, Norfolk County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 61 km from the middle of the area, began a volume at 00:32 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
Oct 21, 8:31 PM EDT	FLOOD	Westborough, MA	MILK STREET AND THE INTERSECTION OF ROUTES 135 AND 9 WERE FLOODED AND IMPASSABLE.
Oct 21, 8:39 PM EDT	FLOOD	Ayer, MA	WEST MAIN STREET WAS CLOSED DUE TO FLOODING.
Oct 21, 8:52 PM EDT	FLASH FLOOD	Wayland, MA	EAST PLAIN AND SCHOOL STREETS WERE FLOODED AND IMPASSABLE. INTERSECTION OF ROUTES 30 AND 27 WAS FLOODED HALFWAY UP THE TIRES. WINDY HILL LANE NEAR COUNTRY CLUB AND STORM BRIDGE ROAD AND ROUTE 126 WERE FLOODED OUT.
Oct 21, 8:53 PM EDT	FLASH FLOOD	Shrewsbury, MA	GOLD STREET WAS FLOODED WITH WATER RUSHING OVER THE ROAD.
Oct 21, 9:00 PM EDT	FLOOD	Wayland, MA	SECTION OF PLAIN ROAD WAS FLOODED.
Oct 21, 9:00 PM EDT	FLOOD	Wayland, MA	SECTION OF ROUTE 20 FLOODED AND IMPASSABLE. SECTION OF MAYS LANE FLOODED. OLD CONNECTICUT PATH BY WAYLAND HIGH SCHOOL WAS FLOODED WITH WATER UP TO THE TIRES OF CARS.
Oct 21, 9:23 PM EDT	FLOOD	Wayland, MA	ROUTE 27 BY THE FIRE STATION WAS FLOODED OUT.
Oct 21, 9:32 PM EDT	FLOOD	Concord, MA	ROUTE 62 NEAR WEST CONCORD FIRE STATION WAS FLOODED UP TO THE BOTTOM OF AN SUV DOOR.
Oct 21, 9:32 PM EDT	FLOOD	Milford, MA	ONE FOOT OF STREET FLOODING ON WATER STREET NEAR MAYHEW ROAD.
Oct 21, 9:32 PM EDT	FLOOD	Tyngsboro, MA	SEVERAL STREETS WERE FLOODED AND IMPASSABLE. PD CLOSED SEVERAL OF THESE STREETS.
Oct 21, 9:39 PM EDT	FLOOD	Pepperell, MA	TWO SECONDARY ROADS WERE FLOODED.
Oct 21, 9:50 PM EDT	FLOOD	Wayland, MA	CAR STUCK IN FLOOD WATERS AT THE INTERSECTION OF PEQUOT ROAD AND HAPPY HOLLOW ROAD.
Oct 21, 9:52 PM EDT	FLOOD	Concord, MA	MAIN STREET UNDER THE BRIDGE WAS FLOODED WITH TWO FEET OF WATER.
Oct 21, 10:06 PM EDT	FLOOD	Lexington, MA	LINCOLN STREET NEAR TEMPLE ISAIAH/LINCOLN FIELDS AND MERRITT ROAD/ROUTE 2 WERE FLOODED OUT.
Oct 21, 10:22 PM EDT	FLOOD	Waltham, MA	TWO CARS WERE STUCK IN FLOOD WATERS AT THE INTERSECTION OF SOUTH AND SUNNYSIDE STREETS.

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

The nearest sounding before it

Chatham, MA (KCHH), launched 00:00Z, 0.5 hours before the alert went out and 146 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: 349 J/kg
Mixed-layer CIN: -88 J/kg
Mixed-layer LCL: 566 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: 95 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

168 
WGUS51 KBOX 220028
FFWBOX
MAC017-021-027-220230-
/O.NEW.KBOX.FF.W.0007.161022T0028Z-161022T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
828 PM EDT FRI OCT 21 2016

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WESTERN NORFOLK COUNTY IN EASTERN MASSACHUSETTS...
  EASTERN WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  MIDDLESEX COUNTY IN NORTHEASTERN MASSACHUSETTS...

* UNTIL 1030 PM EDT

* AT 827 PM EDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
  HEAVY RAIN ACROSS THE WARNED AREA. UP TO TWO INCHES OF RAIN HAVE
  ALREADY FALLEN IN SOME LOCATIONS.  AN ADDITIONAL 1 TO 2 INCHES OR
  RAIN IS EXPECTED. FLASH FLOODING IS EXPECTED TO BEGIN SHORTLY.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  WORCESTER...LOWELL...NEWTON...FRAMINGHAM...WALTHAM...LEOMINSTER...
  FITCHBURG...BILLERICA...MARLBOROUGH...SHREWSBURY...CHELMSFORD...
  CUMBERLAND...ANDOVER...NATICK...FRANKLIN...LEXINGTON...DRACUT...
  TEWKSBURY AND NEEDHAM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

&&

LAT...LON 4267 7124 4266 7125 4262 7118 4202 7127
      4201 7130 4203 7175 4271 7176 4270 7129
      4273 7126

$$

FRANK

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 21, 8:08 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Norfolk, Suffolk	52 min
Oct 21, 8:11 PM EDT	Areal Flood Warning	BOX	Middlesex, Norfolk, Worcester	2 hr
Oct 21, 9:01 PM EDT	Areal Flood Warning	BOX	Worcester	3 hr
Oct 21, 9:17 PM EDT	Areal Flood Warning	BOX	Essex, Middlesex, Norfolk, Plymouth, Suffolk	3 hr
Oct 21, 9:58 PM EDT	Flash Flood Warning	BOX	Essex, Middlesex, Norfolk, Plymouth, Suffolk	2 hr
Oct 21, 10:11 PM EDT	Areal Flood Advisory	BOX	Barnstable, Bristol, Dukes, Norfolk, Plymouth	2 hr
Oct 22, 4:04 AM EDT	Wind Advisory	BOX	Barnstable, Bristol, Dukes, Essex, Franklin, Hampden and 7 more	38 hr

Nearby

Flash Flood Warnings in Massachusetts, 2016 Every flash flood warning in 2016

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.