Severe Thunderstorm Watch 498

Issued

Sep 14, 2021, 3:08 PM EDT (19:08 UTC)

Expired

Sep 14, 2021, 10:13 PM EDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Detroit radar (KDTX), 36 km from the middle of the area, began a volume at 19:08 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

20%

One or more hailstones of 2 inches or more

10%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 1744 Severe potential...watch possibleSep 14, 2:12 PM EDT
• Mesoscale Discussion 1748 Severe thunderstorm watch 498Sep 14, 6:04 PM EDT
• Mesoscale Discussion 1750 Severe potential...watch unlikelySep 14, 7:46 PM EDT

815 
WWUS20 KWNS 141906
SEL8  
SPC WW 141906
INZ000-MIZ000-OHZ000-LEZ000-LHZ000-LMZ000-150300-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 498
NWS Storm Prediction Center Norman OK
305 PM EDT Tue Sep 14 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Northern Indiana
  Southern and eastern Lower Michigan
  Extreme northwestern Ohio
  Lake Erie
  Lake Huron
  Lake Michigan

* Effective this Tuesday afternoon and evening from 305 PM until
  1100 PM EDT.

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

SUMMARY...Thunderstorm development is underway, and additional
storms will form and intensify this afternoon in multiple bands
along and ahead of a surface cold front.  The storm environment
favors a mix of storm clusters (with some supercell structures
possible) and line segments, with damaging winds to 70 mph and
isolated large hail of 1 to 1.5 inch diameter possible through late
evening.

The severe thunderstorm watch area is approximately along and 70
statute miles east and west of a line from 55 miles north northeast
of Bad Axe MI to 40 miles west southwest of Fort Wayne IN. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU8).

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 550. Mean storm motion vector
26040.

...Thompson

Severe Thunderstorm Watches in Michigan, 2021Severe Thunderstorm Watches in Indiana, 2021Severe Thunderstorm Watches in Ohio, 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.