Severe Thunderstorm Watch 247

Issued

Jun 8, 2021, 3:52 PM MDT (21:52 UTC)

Expired

Jun 8, 2021, 11:00 PM MDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

3 in

Strongest gust expected

70 kt

Counties Carter County, MT, Custer County, MT, Daniels County, MT, Dawson County, MT, Fallon County, MT, Garfield County, MT, McCone County, MT, Prairie County, MT, Richland County, MT, Roosevelt County, MT, Rosebud County, MT, Sheridan County, MT, Valley County, MT, Wibaux County, MT

The Glasgow radar (KGGW), 140 km from the middle of the area, began a volume at 21:53 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

70%

One or more gusts of 65 knots or more

60%

Ten or more severe hail reports

70%

One or more hailstones of 2 inches or more

60%

Six or more combined severe hail and wind reports

95%

• Mesoscale Discussion 887 Severe potential...watch likelyJun 8, 2:39 PM MDT
• Mesoscale Discussion 890 Severe thunderstorm watch 247Jun 8, 6:15 PM MDT

111 
WWUS20 KWNS 082150
SEL7  
SPC WW 082150
MTZ000-090500-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 247
NWS Storm Prediction Center Norman OK
355 PM MDT Tue Jun 8 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Eastern Montana

* Effective this Tuesday afternoon and evening from 355 PM until
  1100 PM MDT.

* Primary threats include...
  Scattered damaging winds and isolated significant gusts to 80
    mph likely
  Scattered large hail and isolated very large hail events to 3
    inches in diameter likely
  A tornado or two possible

SUMMARY...Severe thunderstorm development is expected in the next
1-2 hours across eastern Montana, and storms will persist through
late evening while spreading northeastward.  The storm environment
favors a mix of supercells and clusters, with the primary threats of
very large hail (near or larger than the size of baseballs) and
significant damaging winds (up to 80 mph).  An isolated tornado or
two will also be possible with any supercells interacting with the
surface warm front.

The severe thunderstorm watch area is approximately along and 65
statute miles east and west of a line from 60 miles north of Wolf
Point MT to 30 miles south of Broadus MT. For a complete depiction
of the watch see the associated watch outline update (WOUS64 KWNS
WOU7).

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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 246...

AVIATION...A few severe thunderstorms with hail surface and aloft to
3 inches. Extreme turbulence and surface wind gusts to 70 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
22025.

...Thompson

Severe Thunderstorm Watches in Montana, 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.