Area Forecast Discussion
Issued by NWS Missoula, MT
FXUS65 KMSO 052017
Area Forecast Discussion
National Weather Service Missoula MT
217 PM MDT SUN JUL 5 2015
.DISCUSSION...A complex weather scenario continues this afternoon
across western Montana and north central Idaho. At the surface,
the backdoor cold front from yesterday remains stalled from
roughly Lookout Pass through Hamilton to Dillon. This has resulted
in a general north to east wind across much of western Montana.
Winds will remain gusty under this boundary through the evening,
especially in favored areas such as Hellgate Canyon near Missoula
and Badrock Canyon near Kalispell. Flathead Lake has also been
receiving gusty winds, which has caused choppy conditions for
boaters. A Lake Winds Advisory has been issued through this
evening due to these conditions.
Meanwhile, a wave of energy aloft is moving into the area from
Canada. This wave will provide additional lift in the atmosphere
and is expected to interact with the stalled frontal boundary to
allow for a few afternoon and evening thunderstorms to develop.
While thunderstorm coverage is not expected to be very widespread,
the few storms that do develop could become strong due to a
favorable sheared environment. The most likely area to see
stronger storms is along and south of the I-90 Corridor. Gusty
winds, brief heavy rain, small hail and of course lightning will
all be possible with any storms that develop. Showers and
thunderstorms should end abruptly tonight as drier air filters in
to the region behind this wave of energy.
Tomorrow, temperatures will begin to warm again as weak ridging
moves into the area. Overall a pleasant day is expected. A few
afternoon and evening thunderstorms are possible, but should be
mainly confined to southwest Montana and Lemhi County in Idaho.
A cold front dropping down the Rocky Mountain Front on Tuesday
will bring a chance of showers and thunderstorms, especially to
Northwest Montana and along the Divide. Thunderstorms will be
capable of wetting rains but due to recent dryness, lightning
strikes may lead to fire weather concerns across Northwest
Montana. This cold front is not expected to be as strong as the
one that passed through this weekend but gusty easterly winds are
anticipated for the favored locations such as Badrock Canyon on
Tuesday afternoon and evening.
For the remainder of the coming week, temperatures will remain
around 5-10 degrees above normal with Thursday expected to be the
warmest day. Isolated to scattered shower/thunderstorm activity is
anticipated on Wednesday and Thursday, generally south of I-90. By
Friday and Saturday, forecast models are indicating a more active
period as weak disturbances and accompanying surges of moisture
allow for the potential of more widespread thunderstorm activity.
.AVIATION...Breezy northeast to east winds continue today, mainly
across western Montana. KGPI and KMSO are seeing the most steady
winds at 10-20 kts with gusts to 25kts. These winds will continue
through 06/0300z, but should gradually decrease through the
evening. Showers and thunderstorms are expected to develop this
afternoon, mainly along and south of the Interstate 90 corridor.
KBTM, KMSO and KSMN all have a small potential of seeing a
thunderstorm through 06/0300z. There is a small potential for a
couple storms to become strong, which could produce gusty winds,
brief heavy rain and possibly even some small hail. Thunderstorm
activity will decrease rather rapidly late this evening as drier
air moves into the region. There is some potential for KBTM to
experience some low stratus early Monday morning which may obscure
the terrain, likely after 06/0900z.
MT...LAKE WIND ADVISORY until 9 PM MDT this evening Flathead/Mission