Alert archive / Massachusetts / Flash Flood Warnings in 2021
Flash Flood Warning 10, NWS Boston/Norton, MA
NWS Boston/Norton, MA issued this flash flood warning at Jul 17, 2021, 4:58 PM EDT for Hampden County, Massachusetts; Capitol Planning Region, Connecticut. 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 outline as issued.
The facts
- Issued
- Jul 17, 2021, 4:58 PM EDT (20:58 UTC)
- Expired
- Jul 17, 2021, 7:13 PM EDT
- In force
- 2 hr
- Issued by
- NWS Boston/Norton, MA
- Area
- Storm-based polygon
- Flood severity
- None
The radar
The Albany radar (KENX), 126 km from the middle of the area, began a volume at 20:59 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
Albany, NY (KALY), launched 12:00Z, 9.0 hours before the alert went out and 115 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 958 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 83 m²/s²
- 0-3 km storm-relative helicity
- 163 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
553
WGUS51 KBOX 172058
FFWBOX
CTC003-MAC013-180000-
/O.NEW.KBOX.FF.W.0010.210717T2058Z-210718T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
458 PM EDT Sat Jul 17 2021
The National Weather Service in Norton has issued a
* Flash Flood Warning for...
North Central Hartford County in northern Connecticut...
South Central Hampden County in western Massachusetts...
* Until 800 PM EDT.
* At 458 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 2 inches of rain
have fallen. 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...
Springfield, Chicopee, Enfield, Westfield, Agawam, West
Springfield, Longmeadow, Suffield, East Longmeadow, Granby,
Southwick, Hartland and Granville.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4205 7288 4212 7278 4215 7256 4208 7250
4202 7254 4199 7282
FLASH FLOOD...RADAR INDICATED
$$
BL1 follow-up statement
041
WGUS71 KBOX 172313
FFSBOX
Flash Flood Statement
National Weather Service Boston/Norton MA
713 PM EDT Sat Jul 17 2021
CTC003-MAC013-172323-
/O.CAN.KBOX.FF.W.0010.000000T0000Z-210718T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hartford CT-Hampden MA-
713 PM EDT Sat Jul 17 2021
...FLASH FLOOD WARNING IS CANCELLED FOR NORTH CENTRAL HARTFORD AND
SOUTH CENTRAL HAMPDEN COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
A Flash Flood Watch remains in effect until 600 AM EDT Sunday for
portions of northern Connecticut and Massachusetts.
LAT...LON 4205 7288 4212 7278 4215 7256 4208 7250
4202 7254 4199 7282
$$
BLThe office that day
Everything else NWS Boston/Norton, MA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 2:37 PM EDT | Special Weather Statement | BOX | Franklin | 38 min |
| Jul 17, 2:45 PM EDT | Special Weather Statement | BOX | Plymouth | 45 min |
| Jul 17, 2:53 PM EDT | Special Weather Statement | BOX | Hampshire | 52 min |
| Jul 17, 2:53 PM EDT | Severe Thunderstorm Warning | BOX | Bristol, Norfolk | 52 min |
| Jul 17, 3:36 PM EDT | Areal Flood Warning | BOX | Bristol | 114 min |
| Jul 17, 4:05 PM EDT | Severe Thunderstorm Warning | BOX | Worcester | 34 min |
| Jul 17, 4:15 PM EDT | Severe Thunderstorm Warning | BOX | Hampden, Worcester | 60 min |
| Jul 17, 4:34 PM EDT | Severe Thunderstorm Warning | BOX | Middlesex, Worcester | 36 min |
| Jul 17, 4:38 PM EDT | Severe Thunderstorm Warning | BOX | Hampden, Hampshire | 67 min |
| Jul 17, 4:48 PM EDT | Flash Flood Warning | BOX | Worcester | 3 hr |
| Jul 17, 5:10 PM EDT | Severe Thunderstorm Warning | BOX | Middlesex, Worcester | 65 min |
| Jul 17, 5:34 PM EDT | Special Weather Statement | BOX | Hampshire | 41 min |
| Jul 17, 5:35 PM EDT | Flash Flood Warning | BOX | Hampden, Hampshire | 3 hr |
| Jul 17, 6:04 PM EDT | Flash Flood Warning | BOX | Hampden, Hampshire | 3 hr |
| Jul 17, 6:05 PM EDT | Severe Thunderstorm Warning | BOX | Bristol | 26 min |
| Jul 17, 7:49 PM EDT | Areal Flood Warning | BOX | Hampden, Worcester | 116 min |
| Jul 17, 1:59 PM EDT | Special Weather Statement | BOX | 46 min | |
| Jul 17, 3:26 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 64 min |
| Jul 17, 3:47 PM EDT | Areal Flood Warning | BOX | Northeastern Connecticut Planning Region | 118 min |
| Jul 17, 4:14 PM EDT | Flash Flood Warning | BOX | Northeastern Connecticut Planning Region | 5 hr |
| Jul 17, 4:18 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 57 min |
| Jul 17, 4:20 PM EDT | Special Weather Statement | BOX | 40 min | |
| Jul 17, 4:29 PM EDT | Severe Thunderstorm Warning | BOX | Northeastern Connecticut Planning Region | 61 min |
| Jul 17, 5:21 PM EDT | Flash Flood Warning | BOX | Capitol Planning Region, Northeastern Connecticut Planning Region | 5 hr |
| Jul 17, 5:30 PM EDT | Flash Flood Warning | BOX | Northeastern Connecticut Planning Region | 3 hr |
Nearby
Flash Flood Warnings in Massachusetts, 2021Flash Flood Warnings in Connecticut, 2021Every flash flood warning in 2021
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.