Lake Wind Advisory 7, NWS Missoula, MT

865 
WWUS75 KMSO 230018
NPWMSO

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
618 PM MDT FRI JUL 22 2016


MTZ003-230300-
/O.CON.KMSO.LW.Y.0007.000000T0000Z-160723T0300Z/
FLATHEAD/MISSION VALLEYS-
618 PM MDT FRI JUL 22 2016

...LAKE WIND ADVISORY REMAINS IN EFFECT UNTIL 9 PM MDT THIS
EVENING...

* IMPACTS/TIMING: WINDS HAVE BEGUN TO DECREASE THIS EVENING TO 10
  TO 20 MPH. ALTHOUGH WINDS HAVE DECREASED, THUNDERSTORMS LOOK TO
  PASS NEAR AND OVER FLATHEAD LAKE BETWEEN 7PM AND 9PM. THESE
  STORMS WILL KEEP A THREAT OF GUSTY AND ERRACTIC WINDS ALONG WITH
  LIGHTNING AND HAIL.

* WINDS: 10 TO 20 MPH THROUGH THIS EVENING. LOCAL STRONGER GUSTS
  ARE EXPECTED NEAR STORMS THROUGH AROUND 9PM.

* LOCATIONS IMPACTED INCLUDE...FLATHEAD LAKE...POLSON

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A LAKE WIND ADVISORY INDICATES THAT WINDS WILL CAUSE ROUGH CHOP
ON FLATHEAD. SMALL BOATS WILL BE ESPECIALLY PRONE TO CAPSIZING.

NOTE...THE EXPERIMENTAL WAVE HEIGHT FORECASTS ARE REPRESENTATIVE
OF THE MID LAKE WATERS AND DOWNWIND SHORES. WAVE HEIGHTS MAY BE
SIGNIFICANTLY LESS ON UPWIND SHORES.

&&

$$

640 
WWUS75 KMSO 230301
NPWMSO

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
901 PM MDT FRI JUL 22 2016

MTZ003-230415-
/O.EXP.KMSO.LW.Y.0007.000000T0000Z-160723T0300Z/
FLATHEAD/MISSION VALLEYS-
901 PM MDT FRI JUL 22 2016

...LAKE WIND ADVISORY HAS EXPIRED...

WINDS HAVE DECREASED AND THE MAIN THUNDERSTORM THREAT HAS ENDED.

$$

Area Forecast Discussion
National Weather Service Missoula MT
355 AM MDT Fri Jul 22 2016

.DISCUSSION...
A low pressure system is moving toward the Northern Rockies this
morning, and a few isolated showers/thunderstorms have already
developed ahead of it in northwest Montana. These isolated showers
will continue to be ongoing through the morning hours. Current
satellite indicates a second wave of moisture will make its way
eastward by mid-day, this combined with any daytime surface
heating and enhanced shear from the low, will favor more
widespread development of showers and thunderstorms for northwest
Montana this afternoon and evening. Latest hi-resolution models
also show some isolated convection could form as far south as
Idaho County. Storms that do become stronger/more organized will
produce brief heavy rain, gusty winds, lightning, and the
potential for small hail...all which could impact ongoing outdoor
activities at fairs, lakes, and parks.

Winds will become fairly breezy across the area ahead and along
the approaching cold front today, especially for southwest
Montana and Lemhi County, Idaho where fire weather concerns are anticipated
this afternoon and evening. Windy weather across the area could
also result in choppy conditions on area lakes (Flathead Lake)
later today. Lastly, max temperatures will reach around normal for
this time of year as the cooler air mass replaces the warm ridge
that was in place yesterday.

As the low exits the area, a few lingering showers are possible
for far northwest Montana Saturday afternoon. Otherwise, a return
to a warmer and drier pattern is forecast for the weekend into
early next week. Long-range models are indicating that a few
disturbances could bring additional showers/thunderstorms and
breezy afternoon winds to western Montana for mid to late week,
but confidence is low at this time.

&&

.AVIATION...Isolated showers and thunderstorms will track through
northwest Montana through the morning ahead of an approaching cold
front. Expect increasing clouds for KGPI, and an increase in
showers and thunderstorms in the vicinity of KGPI throughout the
afternoon and evening hours. Stronger storms that develop in
northwest Montana could bring threats of heavy rain, restrictions
in terrain visibility, gusty winds, lightning, and small hail. In
addition, all TAF sites will have an increase in westerly winds
today as the cold front moves through, with wind gusts reaching
20-30 kts after 22/1800Z. Latest model soundings support wind
gusts in excess of 30 kts at times for the KBTM air field throughout
the afternoon.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Red Flag Warning from 1 PM this afternoon to midnight MDT
     tonight Deerlodge/West Beaverhead...East Beaverhead.

ID...&&