Special Weather Statement, NWS Missoula, MT

Area Forecast Discussion
National Weather Service Missoula MT
234 PM MDT Fri Jul 16 2021

.DISCUSSION...A substantial plume of smoke is moving through the
region from the fires in northern California and south central
Oregon. Most of the smoke has remained elevated, but could mix
into valleys and cause even lower visibility. The smoke is also
keeping temperatures from warming as quickly as they could, with
most sites showing at least a few degrees behind this time
yesterday. Cumulus clouds are developing in central Idaho and
radar projections show these becoming thunderstorms in southwest
Montana and possibly into west central Montana this afternoon.
Smoke will cause stability in west central Montana, so confidence
in any thunderstorm development north of Butte is low.

The outlook for the weekend remains hot, dry, and smoky under
building high pressure. The forecast maintains very hot but
smoke may keep high temperatures from reaching full warming
potential.

Model guidance maintains agreement that monsoon moisture will
begin to enter the region during Monday, which is when
thunderstorm chances return. Thunderstorm coverage is likely to
increase on Tuesday and Wednesday. The amount of moisture expected
to arrive to north central Idaho and western Montana is pointing
toward thunderstorms that could produce heavy rain and even flash
flooding.

&&

.AVIATION...Smoke from Oregon, northern California, and Idaho
continue to plague the aerial dome over the Northern Rockies for
the next several days. Dependent on the path of the heaviest
smoke, terminals should continue to be prepared for visibility
reductions down to MVFR, especially during the morning hours. A
few showers and thunderstorms are starting to develop across
portion of central Idaho and southwest Montana, behind the latest
smoke plume. Convection will impact KSMN until 07/03z and KBTM
might experience storms between 06/23z to 07/04z.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

Special Weather Statement
National Weather Service Missoula MT
311 PM MDT Fri Jul 16 2021

IDZ009-010-162200-
Eastern Lemhi County ID-Western Lemhi County ID-
311 PM MDT Fri Jul 16 2021

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL LEMHI COUNTY UNTIL 400 PM
MDT...

At 310 PM MDT, Doppler radar was tracking a strong thunderstorm 12
miles southwest of Salmon, moving northeast at 15 mph.

Pea size hail and winds in excess of 30 mph will be possible with
this storm.

Locations impacted include...
Salmon, Carmen, Williams Lake and Baker.

LAT...LON 4493 11410 4508 11423 4529 11385 4506 11366
TIME...MOT...LOC 2110Z 239DEG 13KT 4505 11408

Special Weather Statement
National Weather Service Missoula MT
617 PM MDT Fri Jul 16 2021

MTZ007-170100-
Butte/Blackfoot Region MT-
617 PM MDT Fri Jul 16 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN DEER LODGE AND
SILVER BOW COUNTIES UNTIL 700 PM MDT...

At 616 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 9 miles west of Divide to near Silver Star.
Movement was northeast at 20 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Butte, Silver Bow, Walkerville, Gregson Hot Springs, Nissler,
Crackerville, Ramsay, Janney and Newcomb.

LAT...LON 4574 11246 4576 11250 4570 11253 4584 11299
      4618 11277 4612 11250 4609 11247 4607 11246
      4605 11248 4602 11244 4593 11244 4589 11240
      4585 11243 4575 11219
TIME...MOT...LOC 0016Z 215DEG 19KT 4580 11293 4568 11239

Special Weather Statement
National Weather Service Missoula MT
628 PM MDT Fri Jul 16 2021

MTZ006-007-170115-
Bitterroot/Sapphire Mountains MT-Butte/Blackfoot Region MT-
628 PM MDT Fri Jul 16 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTH CENTRAL DEER LODGE AND
SOUTHEASTERN GRANITE COUNTIES UNTIL 715 PM MDT...

At 626 PM MDT, Doppler radar was tracking a strong thunderstorm 15
miles southwest of Philipsburg, or 23 miles west of Anaconda, moving
northeast at 15 mph.

Pea size hail and wind gusts up to 50 mph will be possible with this
storm, along with brief heavy rain.

Locations impacted include...
Philipsburg, Georgetown and Porters Corner.

LAT...LON 4601 11340 4611 11362 4642 11340 4628 11308
TIME...MOT...LOC 0026Z 213DEG 14KT 4613 11346

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
646 PM MDT FRI JUL 16 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0536 PM     NON-TSTM WND GST 3 SW SALMON             45.15N 113.95W
07/16/2021  M61 MPH          LEMHI              ID   MESONET

            MESONET STATION SMYI1 SALMON.

&&

Special Weather Statement
National Weather Service Missoula MT
716 PM MDT Fri Jul 16 2021

MTZ006-007-043-170200-
Bitterroot/Sapphire Mountains MT-Butte/Blackfoot Region MT-
Potomac/Seeley Lake Region MT-
716 PM MDT Fri Jul 16 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN MISSOULA...
NORTHEASTERN DEER LODGE...NORTHEASTERN GRANITE...NORTH CENTRAL SILVER
BOW AND SOUTHERN POWELL COUNTIES UNTIL 800 PM MDT...

At 715 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 13 miles northwest of Philipsburg to 7 miles
northeast of Butte. Movement was northeast at 25 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Deer Lodge, Drummond, Philipsburg, Warm Springs, Galen, Garrison,
Maxville, Jens, Princeton, Brock Creek, New Chicago, Bearmouth,
Racetrack, Garnet, Goldcreek, Hall, Elliston and Avon.

LAT...LON 4642 11231 4639 11235 4639 11240 4633 11246
      4634 11247 4633 11253 4630 11257 4627 11256
      4624 11260 4618 11257 4618 11251 4614 11252
      4609 11247 4605 11248 4603 11244 4603 11245
      4643 11362 4687 11335 4652 11229
TIME...MOT...LOC 0115Z 206DEG 23KT 4642 11355 4602 11238