Special Weather Statement, NWS Missoula, MT

Area Forecast Discussion
National Weather Service Missoula MT
239 PM MDT FRI MAY 29 2015

.DISCUSSION...
Isolated to scattered showers will continue to develop this
afternoon/evening across the Northern Rockies, bringing brief
heavy rain, some gusty winds, and a few lightning strikes. The
showers are not expected to be as widespread as previous days,
however.

A disturbance is expected to track through the Northern Rockies
beginning early Saturday morning, which will spread showers and a
few thunderstorms across north central Idaho and portions of
western Montana. Showers and thunderstorms will quickly become
more widespread by mid morning and afternoon as the disturbance
impacts the region. These storms could bring additional brief
heavy rain and lightning that would disrupt weekend outdoor
activities. The wet weather will decrease later Saturday and
become more isolated/scattered by Sunday. Temperatures are
expected to be the warmest of season by Sunday, with 70s and 80s
possible for most areas and 90s in the lower valleys of Idaho.

A stronger, dynamic low pressure system approaches Monday which
will spread showers and thunderstorms across the region Monday and
Tuesday, with the strongest storms expected Monday. Moisture will
be plentiful, so storms that do develop could produce heavy
rainfall and rockslide/mudslide potential for prone/steep terrain.
Other threats such as hail, frequent lightning, and strong wind
gusts cannot be ruled out.

Showers and thunderstorms are expected to continue each
afternoon/evening throughout next week as the area continues to be
influenced by a low pressure system. Temperatures will be several
degrees cooler Tuesday and onward, but still around normal.

&&

.AVIATION...Scattered showers and an isolated thunderstorm are
expected to develop in some areas through 30/0400z. All terminals
have a potential to see a shower or storm. Unsettled weather will
return early Saturday morning in the form of showers. Unstable
conditions will increase with afternoon heating. Showers and
thunderstorms are likely in the vicinity of all terminals.

&&

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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
421 PM MDT FRI MAY 29 2015

MTZ004-005-292245-
MISSOULA/BITTERROOT VALLEYS MT-LOWER CLARK FORK REGION MT-
421 PM MDT FRI MAY 29 2015

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN SANDERS...WEST
CENTRAL MISSOULA AND SOUTHEASTERN MINERAL COUNTIES UNTIL 445 PM
MDT...

AT 418 PM MDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM
OVER ALBERTON...OR 23 MILES SOUTHEAST OF SUPERIOR...MOVING NORTHEAST
AT 25 MPH.

PEA SIZE HAIL...BRIEF HEAVY RAIN AND WINDS NEAR 40 MPH WILL BE
POSSIBLE WITH THIS STORM. ALSO WATCH FOR BRIEF PONDING OF WATER ON I-
90.

LOCATIONS IMPACTED INCLUDE...
ALBERTON...FRENCHTOWN...CYR...NINEMILE AND HUSON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

&&

LAT...LON 4689 11455 4698 11467 4721 11436 4707 11418
TIME...MOT...LOC 2218Z 225DEG 25KT 4698 11450