Fire Weather Watch 3, NWS Missoula, MT

206 
WWUS85 KMSO 211817
RFWMSO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Missoula MT
1217 PM MDT Wed Jul 21 2021

MTZ110-230400-
/O.CAN.KMSO.FW.A.0003.210722T1800Z-210723T0300Z/
/O.NEW.KMSO.FW.A.0004.210723T1800Z-210724T0300Z/
Deerlodge/West Beaverhead-
1217 PM MDT Wed Jul 21 2021

...FIRE WEATHER WATCH IN EFFECT FROM FRIDAY AFTERNOON THROUGH
FRIDAY EVENING...
...FIRE WEATHER WATCH IS CANCELLED...

The National Weather Service in Missoula has cancelled the Fire
Weather Watch. 

* Affected area: Fire Zone 110 (Deerlodge/West Beaverhead). 

* Impacts: The combination of gusty winds and low humidity may 
  produce critical fire weather conditions. 

* Winds: Northwest 20 to 25 mph with gusts to around 35 mph.

* Minimum humidities: 10 to 15 percent.

&&

$$

IDZ103-MTZ104-106-108-109-211930-
/O.CAN.KMSO.FW.A.0003.210722T1800Z-210723T0300Z/
Clearwater/Nez Perce-Kootenai-West Lolo-East Lolo-Bitterroot-
1217 PM MDT Wed Jul 21 2021 /1117 AM PDT Wed Jul 21 2021/

...FIRE WEATHER WATCH IS CANCELLED...

The National Weather Service in Missoula has cancelled the Fire
Weather Watch. 

The cold front timing has slowed so the minimum humidity will not
be as dry. 

$$

MTZ105-107-230300-
/O.UPG.KMSO.FW.A.0003.210722T1800Z-210723T0300Z/
/O.NEW.KMSO.FW.W.0010.210722T1800Z-210723T0300Z/
Flathead/Glacier Park-Salish and Kootenai Reservation-
1217 PM MDT Wed Jul 21 2021

...RED FLAG WARNING IN EFFECT FROM NOON TO 9 PM MDT THURSDAY...

The Fire Weather Watch is no longer in effect. 

* Affected area: Fire Zone 105 (Flathead/Glacier Park). Fire 
  Zone 107 (Salish and Kootenai Reservation). 

* Impacts: The combination of gusty winds and low humidity will 
  produce critical fire weather conditions. 

* Winds: Southwest to west 20 to 25 mph with gusts to 30 to 35 
  mph.

* Minimum humidities: 10 to 15 percent.

&&

$$

IDZ102-220400-
/O.CON.KMSO.FW.W.0009.000000T0000Z-210722T0400Z/
Palouse/Hells Canyon-
1117 AM PDT Wed Jul 21 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT THIS
EVENING...

* Affected area:
   Fire Zone 102 (Palouse/Hells Canyon).

* Impacts: The combination of gusty winds and low humidity will 
  produce critical fire weather conditions. 

* Winds: West to northwest 15 to 20 mph with gusts to 25 to 30 
  mph. 

* Minimum humidities: 15 to 20 percent.

&&

$$

MTZ111-230400-
/O.NEW.KMSO.FW.A.0004.210723T1800Z-210724T0300Z/
East Beaverhead-
1217 PM MDT Wed Jul 21 2021

...FIRE WEATHER WATCH IN EFFECT FROM FRIDAY AFTERNOON THROUGH
FRIDAY EVENING...

* Affected area: Fire Zone 111 (East Beaverhead). 

* Impacts: The combination of gusty winds and low humidity may 
  produce critical fire weather conditions. 

* Winds: Northwest 20 to 25 mph with gusts to around 35 mph.

* Minimum humidities: 10 to 15 percent.

&&

$$

Area Forecast Discussion
National Weather Service Missoula MT
354 AM MDT Tue Jul 20 2021

.DISCUSSION...Little has changed with the upper level pattern as
southwest flow remains over western Montana and central Idaho
today. Waves of monsoonal moisture continue to rotate around the
ridge of high pressure anchored in the Four Corners region. A
shortwave of energy will move through the southwest flow aloft
this afternoon and evening to interact with the monsoonal
moisture, creating showers and thunderstorms. There is HIGH
confidence in thunderstorm development this afternoon across
southern Idaho County, Lemhi County and southwest Montana, then
shifting into west-central Montana this evening. Thunderstorms
could reach into northwest Montana as well, but given the best
forcing is expected further south, confidence in storms is lower
here. Dewpoints have risen into the 50s and 60s across much of
the area, and with abnormal amounts of atmospheric moisture in
place, storms today will be capable of producing very heavy rain
under their cores. Flash flooding remains a possibility for
localized flood prone areas, particularly across Lemhi County and
southwest Montana. In addition to rainfall, gusty outflow winds
will remain a concern with any storms that develop. The most
recent high resolution models show gust potential with storms up
to 50 mph.

Thunderstorm activity is expected to decrease from west to east
through the evening hours, with storms lingering along the
Continental Divide until shortly after sunset. Forecast models do
indicate the potential for another round of nocturnal storms late
tonight into Wednesday morning as a wave of energy moves through
the southwest flow aloft. Nocturnal storms look most likely after
midnight through north central Idaho. This activity will likely
shift into northwest Montana (generally from Missoula northward)
early Wednesday morning.

Wednesday still looks like a transition day as a cold front
approaches the region from the west. Drier air will begin to move
into far northwest Montana ahead of this feature, while moist air
remains in place across southwest Montana. More thunderstorms are
likely, with a few stronger storms anticipated as jet energy
punches into the region.

The cold front will move through the region on Thursday, bringing
breezy winds and much drier air. This very well could create
critical fire weather conditions across much of the region. A few
thunderstorms are possible once again, but should be mainly
limited to far southwest Montana.

&&

.AVIATION...Localized fog is possible this morning as the low
levels of the atmosphere have moistened up. Any fog that does
develop will likely be short lived, dissipating shortly after
sunrise. Smoke from local and regional wildfires will continue to
cause lowered visibility at area terminals today and into the
foreseeable future. Monsoonal moisture is expected to interact
with a wave of energy this afternoon and evening to produce
showers and thunderstorms across much of western Montana and
central Idaho. Confidence is HIGH that thunderstorms will be
relatively widespread across southern Idaho county, Lemhi County
and southwest Montana, spreading into west- central Montana this
evening. The main threats with storms will be locally very heavy
rain and gusty outflow winds, possibly approaching 45 kts. This
activity looks most likely around KSMN between 20/2100z and
21/0100z, KBTM between 20/2300z and 21/0200z and KMSO between
21/0000z and 21/0300z. KGPI has lesser chances of seeing a storm.
Storms will dissipate from west to east this evening. However,
another wave of energy is expected to initiate nocturnal
convection late tonight (after 21/0600z) across north central
Idaho, possibly shifting into portions of northwest Montana after
21/1200z.

&&

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

&&