Alert archive / Massachusetts / Flash Flood Warnings in 2019

Flash Flood Warning 3, NWS Boston/Norton, MA

July 12, 2019Plymouth County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Jul 12, 2019, 6:13 AM EDT for Plymouth County, Massachusetts. It was in force for 2 hr. 7 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 12, 2019, 6:13 AM EDT (10:13 UTC)
Expired: Jul 12, 2019, 8:15 AM EDT
In force: 2 hr
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Flood severity: None

County Plymouth County, MA

The radar

The Boston radar (KBOX), 43 km from the middle of the area, began a volume at 10:16 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 12, 6:56 AM EDT	FLOOD	Plymouth, MA	REPORTED SEVERAL AREA OF SIGNIFICANT FLOODING WITH NO DEPTH GIVEN
Jul 12, 7:00 AM EDT	FLOOD	Kingston, MA	KINGSTON TRAIN STATION PARKING LOT CLOSED DUE TO FLOODING.
Jul 12, 7:15 AM EDT	HEAVY RAIN 5.08	Plymouth, MA
Jul 12, 7:17 AM EDT	FLOOD	Plymouth, MA	SACRIFICE ROCK ROAD CLOSED DUE TO FLOODING AND ROAD WASHOUT AT LONG RIDGE ROAD.
Jul 12, 7:28 AM EDT	FLOOD	Plymouth, MA	STATE ROAD CLOSED DUE TO FLOODING
Jul 12, 7:40 AM EDT	FLOOD	Plymouth, MA	BASEMENT FLOODED UP TO THE FURNACE ON SANDWICH STREET
Jul 12, 8:10 AM EDT	HEAVY RAIN 5.69	Plymouth, MA

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, 10.2 hours before the alert went out and 60 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1358 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 57 m²/s²
0-3 km storm-relative helicity: 49 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

133 
WGUS51 KBOX 121013
FFWBOX
MAC023-121215-
/O.NEW.KBOX.FF.W.0003.190712T1013Z-190712T1215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
613 AM EDT Fri Jul 12 2019

The National Weather Service in Boston/Norton has issued a

* Flash Flood Warning for...
  Southeastern Plymouth County in southeastern Massachusetts...

* Until 815 AM EDT.

* At 610 AM EDT, Doppler radar indicated heavy rain continuing to 
  move across the warned area. Two to four inches of rain have 
  fallen, and additional heavy rainfall with rates of locally 1 to 2 
  inches per hour will result in flash flooding.

* Some locations that will experience flooding include...
  Plymouth, Marion, Middleborough, Wareham, Bourne, Duxbury,
  Kingston, Carver, Rochester and Plympton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 4181 7054 4179 7055 4172 7085 4192 7091
      4207 7062 4201 7058 4198 7062 4195 7057
      4180 7053

$$

KJC

2 follow-up statements

501 
WGUS71 KBOX 121130
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
730 AM EDT Fri Jul 12 2019

MAC023-121215-
/O.CON.KBOX.FF.W.0003.000000T0000Z-190712T1215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Plymouth MA-
730 AM EDT Fri Jul 12 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 AM EDT FOR
SOUTHEASTERN PLYMOUTH COUNTY...

At 724 AM EDT, Doppler radar indicated heavy rain continuing to move 
across the warned area. Up to 5 inches of rain have fallen in and 
around Plymouth. Rainfall rates are starting to diminish and the 
heavy rainfall will move to the east during the next hour.

Several reports of road closures and washouts have been received. 

Some locations that will experience flooding include...
Plymouth, Marion, Middleborough, Wareham, Bourne, Duxbury, Kingston,
Carver, Rochester and Plympton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 4181 7054 4179 7055 4172 7085 4192 7091
      4207 7062 4201 7058 4198 7062 4195 7057
      4180 7053

$$

KJC

046 
WGUS71 KBOX 121211
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
811 AM EDT Fri Jul 12 2019

MAC023-121215-
/O.EXP.KBOX.FF.W.0003.000000T0000Z-190712T1215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Plymouth MA-
811 AM EDT Fri Jul 12 2019

...THE FLASH FLOOD WARNING FOR SOUTHEASTERN PLYMOUTH COUNTY WILL
EXPIRE AT 815 AM EDT...

At 805 AM EDT, radar indicated that the thunderstorms that produced 
torrential rainfall earlier this morning had moved east of Plymouth 
County, with light showers diminishing in the area. 

There are still localized road closures due to flooding in the 
Plymouth and Kingston areas, and there are likely other locales 
where poor drainage flooding was still occurring as of 8 am. These 
floodwaters are expected to gradually recede thru mid morning. 
However, renewed flooding is not expected. Therefore the Flash Flood 
Warning is being allowed to expire. 

Please continue to heed any remaining road closures.

LAT...LON 4181 7054 4179 7055 4172 7085 4192 7091
      4207 7062 4201 7058 4198 7062 4195 7057
      4180 7053

$$

NMB

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 12, 3:06 AM EDT	Special Weather Statement	BOX	Bristol	39 min
Jul 12, 3:46 AM EDT	Special Weather Statement	BOX	Bristol, Norfolk, Plymouth, Suffolk	59 min
Jul 12, 4:28 AM EDT	Areal Flood Warning	BOX	Plymouth	2 hr
Jul 12, 5:06 AM EDT	Special Weather Statement	BOX	Bristol	54 min
Jul 12, 5:36 AM EDT	Areal Flood Warning	BOX	Bristol	83 min
Jul 12, 6:39 AM EDT	Areal Flood Warning	BOX	Bristol, Plymouth	111 min
Jul 12, 7:17 AM EDT	Special Weather Statement	BOX	Barnstable, Dukes	58 min
Jul 12, 8:20 AM EDT	Areal Flood Warning	BOX	Barnstable	91 min
Jul 12, 8:25 AM EDT	Special Weather Statement	BOX	Barnstable, Nantucket	35 min

Nearby

Flash Flood Warnings in Massachusetts, 2019 Every flash flood warning in 2019

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.