Severe Thunderstorm Watch 390

Issued

Jul 24, 2021, 3:16 PM EDT (19:16 UTC)

Expired

Jul 24, 2021, 10:00 PM EDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

1 in

Strongest gust expected

60 kt

The Detroit radar (KDTX), 114 km from the middle of the area, began a volume at 19:20 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

20%

One or more EF2 to EF5 tornadoes

5%

Ten or more severe wind reports

40%

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

60%

• Mesoscale Discussion 1339 Severe potential...watch possibleJul 24, 11:44 AM EDT
• Mesoscale Discussion 1340 Severe potential...watch possibleJul 24, 2:21 PM EDT
• Mesoscale Discussion 1343 Severe thunderstorm watch 390...391Jul 24, 6:21 PM EDT
• Mesoscale Discussion 1344 Severe thunderstorm watch 390...391Jul 24, 8:31 PM EDT

485 
WWUS20 KWNS 241913
SEL0  
SPC WW 241913
MIZ000-LHZ000-250200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 390
NWS Storm Prediction Center Norman OK
315 PM EDT Sat Jul 24 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Central and Southern Lower Michigan
  Lake Huron

* Effective this Saturday afternoon and evening from 315 PM until
  1000 PM EDT.

* Primary threats include...
  Scattered damaging wind gusts to 70 mph possible
  Isolated large hail events to 1 inch in diameter possible
  A tornado or two possible

SUMMARY...Multiple lines and clusters of thunderstorms will move
across the watch area this afternoon and early evening, posing a
risk of locally damaging wind gusts and isolated hail.  A tornado or
two cannot be ruled out.

The severe thunderstorm watch area is approximately along and 65
statute miles north and south of a line from 40 miles east of Oscoda
MI to 35 miles west of Grand Rapids MI. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
WOU0).

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 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
28030.

...Hart

Severe Thunderstorm Watches in Michigan, 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.