Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 56, NWS Boston/Norton, MA
NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 7, 2021, 4:33 PM EDT for Essex County, Middlesex County, Massachusetts. It was in force for 57 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 7, 2021, 4:33 PM EDT (20:33 UTC)
- Expired
- Jul 7, 2021, 5:30 PM EDT
- In force
- 57 min
- Issued by
- NWS Boston/Norton, MA
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Essex County, MA, Middlesex County, MA
The radar
The Boston radar (KBOX), 76 km from the middle of the area, began a volume at 20:37 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 7, 4:47 PM EDT | HAIL 1 | Methuen, MA | |
| Jul 7, 5:00 PM EDT | TSTM WND DMG | Lawrence, MA | TREE AND POWER LINES DOWN ON LEONARD AVE |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 7, 2:41 PM EDT | Severe Thunderstorm Watch | SPC | 10 hr |
The nearest sounding before it
Gray, ME (KGYX), launched 12:00Z, 8.6 hours before the alert went out and 151 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
- 1184 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 2 m²/s²
- 0-3 km storm-relative helicity
- 30 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
985
WUUS51 KBOX 072033
SVRBOX
MAC009-017-072130-
/O.NEW.KBOX.SV.W.0056.210707T2033Z-210707T2130Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
433 PM EDT Wed Jul 7 2021
The National Weather Service in Boston/Norton has issued a
* Severe Thunderstorm Warning for...
Essex County in northeastern Massachusetts...
Northeastern Middlesex County in northeastern Massachusetts...
* Until 530 PM EDT.
* At 433 PM EDT, a severe thunderstorm was located over Boxford, or
near North Andover, moving southeast at 20 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Expect damage to trees and power lines.
* Locations impacted include...
Lynn, Lawrence, Haverhill, Peabody, Methuen, Salem, Beverly,
Andover, Dracut, Tewksbury, Gloucester, North Andover, Danvers,
Wilmington, Marblehead, North Reading, Swampscott, Ipswich,
Lynnfield and Middleton.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4267 7075 4265 7076 4265 7072 4261 7063
4257 7076 4253 7078 4256 7078 4254 7090
4254 7087 4250 7089 4252 7085 4250 7085
4246 7090 4269 7131 4274 7124 4274 7119
4280 7118 4282 7113
TIME...MOT...LOC 2033Z 300DEG 16KT 4265 7104
HAIL...0.75IN
WIND...60MPH
$$
Loconto3 follow-up statements
294
WWUS51 KBOX 072057
SVSBOX
Severe Weather Statement
National Weather Service Boston/Norton MA
457 PM EDT Wed Jul 7 2021
MAC009-017-072130-
/O.CON.KBOX.SV.W.0056.000000T0000Z-210707T2130Z/
Essex MA-Middlesex MA-
457 PM EDT Wed Jul 7 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR ESSEX AND NORTHEASTERN MIDDLESEX COUNTIES...
At 456 PM EDT, a severe thunderstorm was over Andover, or near
Lawrence. Another severe thunderstorm was located over Wenham, or
over Danvers. Each of these storms were moving southeast at 20 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Trained weather spotters. One inch diameter hail was
reported in Methuen at 447 PM.
IMPACT...Expect wind damage to trees and power lines. Minor hail
damage to vehicles is possible.
Locations impacted include...
Lynn, Lawrence, Haverhill, Peabody, Methuen, Salem, Beverly, Andover,
Dracut, Tewksbury, Gloucester, North Andover, Danvers, Wilmington,
Marblehead, North Reading, Swampscott, Ipswich, Lynnfield and
Middleton.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4267 7075 4265 7076 4265 7072 4261 7063
4257 7076 4253 7078 4256 7078 4254 7090
4254 7087 4250 7089 4252 7085 4250 7085
4246 7090 4269 7131 4274 7124 4274 7119
4280 7118 4282 7113
TIME...MOT...LOC 2056Z 300DEG 16KT 4260 7092
HAIL...1.00IN
WIND...60MPH
$$
Loconto757
WWUS51 KBOX 072117 RRA
SVSBOX
Severe Weather Statement
National Weather Service Boston/Norton MA
517 PM EDT Wed Jul 7 2021
MAC009-017-072130-
/O.CON.KBOX.SV.W.0056.000000T0000Z-210707T2130Z/
Essex MA-Middlesex MA-
517 PM EDT Wed Jul 7 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR CENTRAL ESSEX AND NORTHEASTERN MIDDLESEX COUNTIES...
At 516 PM EDT, a severe thunderstorm was located over Middleton, or
near Danvers, moving southeast at 10 mph.
HAZARD...60 mph wind gusts and nickel size hail.
SOURCE...Trained weather spotters. Quarter size hail was reported in
Methuen and trees were downed in Dracut.
IMPACT...Expect damage to trees and power lines.
Locations impacted include...
Lynn, Lawrence, Peabody, Salem, Beverly, Andover, Tewksbury,
Gloucester, North Andover, Danvers, Wilmington, Marblehead, North
Reading, Swampscott, Ipswich, Lynnfield, Middleton, Georgetown,
Boxford and Hamilton.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4267 7075 4265 7076 4265 7072 4261 7063
4257 7076 4253 7078 4256 7078 4254 7090
4254 7087 4250 7089 4252 7085 4250 7085
4246 7090 4264 7122 4269 7119 4271 7115
4273 7112 4274 7104
TIME...MOT...LOC 2116Z 311DEG 9KT 4259 7101
TORNADO...POSSIBLE
HAIL...0.88IN
WIND...60MPH
$$
Loconto460
WWUS51 KBOX 072129
SVSBOX
Severe Weather Statement
National Weather Service Boston/Norton MA
529 PM EDT Wed Jul 7 2021
MAC009-017-072139-
/O.EXP.KBOX.SV.W.0056.000000T0000Z-210707T2130Z/
Essex MA-Middlesex MA-
529 PM EDT Wed Jul 7 2021
...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL ESSEX AND NORTHEASTERN
MIDDLESEX COUNTIES WILL EXPIRE AT 530 PM EDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.
A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
northeastern Massachusetts.
LAT...LON 4267 7075 4265 7076 4265 7072 4261 7063
4257 7076 4253 7078 4256 7078 4254 7090
4254 7087 4250 7089 4252 7085 4250 7085
4246 7090 4264 7122 4269 7119 4271 7115
4273 7112 4274 7104
TIME...MOT...LOC 2129Z 300DEG 16KT 4257 7097
$$
LocontoThe office that day
Everything else NWS Boston/Norton, MA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 4:00 PM EDT | Severe Thunderstorm Warning | BOX | Hampden, Hampshire | 60 min |
| Jul 7, 4:01 PM EDT | Severe Thunderstorm Warning | BOX | Franklin, Hampshire | 59 min |
| Jul 7, 4:05 PM EDT | Special Weather Statement | BOX | Essex | 40 min |
| Jul 7, 5:02 PM EDT | Special Weather Statement | BOX | Worcester | 43 min |
| Jul 7, 5:05 PM EDT | Special Marine Warning | BOX | 25 min | |
| Jul 7, 5:10 PM EDT | Tropical Storm Watch | BOX | Barnstable, Bristol, Dukes, Nantucket, Plymouth | 13 hr |
| Jul 7, 5:21 PM EDT | Severe Thunderstorm Warning | BOX | Hampden, Hampshire, Worcester | 54 min |
| Jul 7, 5:24 PM EDT | Special Marine Warning | BOX | 66 min | |
| Jul 7, 5:30 PM EDT | Severe Thunderstorm Warning | BOX | Hampden, Worcester | 60 min |
| Jul 7, 6:01 PM EDT | Special Weather Statement | BOX | Worcester | 44 min |
| Jul 7, 6:17 PM EDT | Severe Thunderstorm Warning | BOX | Bristol, Middlesex, Norfolk, Worcester | 58 min |
| Jul 7, 6:18 PM EDT | Severe Thunderstorm Warning | BOX | Middlesex, Worcester | 36 min |
| Jul 7, 6:22 PM EDT | Special Marine Warning | BOX | 53 min | |
| Jul 7, 6:59 PM EDT | Severe Thunderstorm Warning | BOX | Bristol, Middlesex, Norfolk, Plymouth, Suffolk | 61 min |
| Jul 7, 7:18 PM EDT | Special Marine Warning | BOX | 57 min | |
| Jul 7, 7:47 PM EDT | Severe Thunderstorm Warning | BOX | Norfolk, Plymouth | 25 min |
| Jul 7, 7:51 PM EDT | Special Marine Warning | BOX | 54 min |
Nearby
Severe Thunderstorm Warnings in Massachusetts, 2021Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.