Severe Thunderstorm Watch 501

Issued

Sep 15, 2021, 11:55 AM EDT (15:55 UTC)

Expired

Sep 15, 2021, 8:00 PM EDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Albany radar (KENX), 76 km from the middle of the area, began a volume at 15:54 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.

Two or more tornadoes

10%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

60%

One or more gusts of 65 knots or more

20%

Ten or more severe hail reports

40%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 1753 Severe potential...watch likelySep 15, 10:33 AM EDT
• Mesoscale Discussion 1754 Severe potential...watch likelySep 15, 11:59 AM EDT
• Mesoscale Discussion 1757 Severe thunderstorm watch 501...502Sep 15, 4:38 PM EDT

495 
WWUS20 KWNS 151552
SEL1  
SPC WW 151552
MAZ000-NYZ000-PAZ000-VTZ000-160000-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 501
NWS Storm Prediction Center Norman OK
1150 AM EDT Wed Sep 15 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Extreme western Massachusetts
  Central and eastern New York
  Central and northeastern Pennsylvania
  Vermont

* Effective this Wednesday morning and evening from 1150 AM until
  800 PM EDT.

* Primary threats include...
  Scattered damaging wind gusts to 70 mph likely
  Scattered large hail events to 1.5 inches in diameter possible

SUMMARY...Scattered severe storms are expected to form by early
afternoon along and just ahead of a surface cold front from
Pennsylvania into New York/Vermont.  The initial storms will be
semi-discrete and a few could have supercell structures, but the
longer-term trend will be for storms to grow into bands/line
segments through the afternoon.  Damaging winds of 60 to 70 mph will
be the main threat, along with isolated large of 1 to 1.5 inch
diameter.

The severe thunderstorm watch area is approximately along and 65
statute miles north and south of a line from 25 miles south of
Montpelier VT to Altoona PA. For a complete depiction of the watch
see the associated watch outline update (WOUS64 KWNS WOU1).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
25035.

...Thompson

Severe Thunderstorm Watches in Pennsylvania, 2021Severe Thunderstorm Watches in New York, 2021Severe Thunderstorm Watches in Vermont, 2021Every severe thunderstorm watch in 2021

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.