Scientific Forecaster Discussion
fxus65 kmso 200951
Area forecast discussion
National Weather Service Missoula Montana
351 am MDT Thu Jul 20 2017
Discussion...already a few night-time thunderstorms have
developed across eastern Washington and over the Idaho Panhandle
and are moving northeastward towards Canada. There is a chance
that portions of Lincoln and Flathead counties may see a sprinkle
or even a stray lightning strike this morning before this wave
exits. The wind gradient is expected to tighten today causing
gusty westerly winds across the region. Though wind gusts are
expected to remain below 25 mph most areas, portions of Lemhi
County and areas south of Butte could see gusts to 35 mph. Those
recreating with small craft on area lakes should take caution.
Breezy conditions will continue Friday and to a lesser extent into
the weekend. Temperatures will be a little cooler with high
temperatures a little below normal but quite pleasant on Friday
warming to above normal by Sunday. No precipitation is expected
through the weekend.
Changes in the forecast for next week were mainly focused on
thunderstorms and rain. The ridge over the region continues to
dominate, but models are trying to bring a series of stronger
disturbances ejected out of a deepening Aleutian low next week.
These disturbances will interact with monsoon moisture from the
southwest causing more thunderstorms and showers. The timing and
main areas of convection have not yet settled down in the models,
but there has consistently been some sort of disturbance for next
week in the models for over 24 hours now. Overall this pattern
change is being driven by a deepening Aleutian low and the ridge
axis currently over the region moving east out over the plains.
Longer range outlooks beyond 7-days remain warmer and drier than
average for the region, which is an indication that this will
probably only be a temporary change and much of the west will once
again be under a ridge later this Summer.
Aviation...as of 20/0933z showers and a few thunderstorms were
located over northeastern Washington and northern Idaho state.
There is a chance that an isolated thunderstorm could form over
northwest Montana through 20/1800z with lightning the main threat. An
increased westerly wind gradient will result in gusts to 25 knots
across western Montana and north-central Idaho between 20/2000z
Montana...red flag warning from noon today to 9 PM MDT this evening for