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fxus66 kotx 221733 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
1033 am PDT Sat Jul 22 2017

Synopsis...
clouds will dissipate through the afternoon with warmer
temperatures back up into the 90s this weekend. A breezy cold
front will arrive Sunday night but will have only a minimal impact
on temperatures on Monday. An increasing chance of thunderstorms
will occur by mid-week and the remainder of the work week will be
cooler and breezy.

&&

Discussion...

..breezy winds down the Okanogan Valley into the western
Columbia Basin Sunday evening through Monday afternoon...

Today through early sunday: there is a broad upper level ridge
with moisture streaming across in the way of mid and high level
clouds across the forecast area this morning. The clouds are
expected to thin and dissipate as the afternoon progresses. There
is a slight chance of a sprinkle or very light rain along the
crest of the northern Cascades...mainly near the Canadian border
today. There is some instability...NAM is of course showing
more...GFS less. Have confined the thunder threat to an area
within 15 miles or so of the US/Canadian border in the Cascades.
Temps today will be about 2-4 degrees above average, or valley
temps in the mid 80s to mid 90s. Then Sunday ahead of the cold
front we will see about 3-6 degrees of warming. The exception to
this will be across the Cascade valleys where their temps will be
similar to todays. Low temps will be 4-8 degrees above average.

Late sunday: a closed low pressure system will sweep across
Canada Sunday. This will bring a strong dry cold front across our
region. Winds will start to pick up late Sunday afternoon. The
area of greatest concern is northerly winds funneling down the
Okanogan Valley into portions of the Waterville Plateau and parts
of the western Columbia Basin. Models seem to have sped up the
timing a bit and have the winds increasing by 5pm, and have them
really start blowing by 8pm down the Okanogan. Gusts to 35 mph is
expected with the potential of some isolated locations seeing
gusts to 40 mph. Strong west to northwest winds is also expected
across the Wenatchee valley as well during the evening hours.
Wenatchee valley winds will decrease after midnight. However the
winds down the Okanogan into the basin will keep going.

Monday: the northerly winds will continue down the Okanogan into
the Columbia Basin through the morning. It isn't until mid Monday
afternoon that the winds will start to subside. Dry conditions
will continue with mostly sunny skies. Temperatures will not cool
as substantially as many would like. We will see about 2-4 degrees
of cooling compared to Sunday. /Nisbet

Monday night through saturday: the models have pushed back the
monsoonal moisture from the low over California moving into the
area from the previous run. The area of chance of thunder and
precip was diminished to just along the Oregon border and Snake
River Valley areas for Tuesday. This pushed of moisture is now
slated for the Wednesday afternoon period but model
inconsistencies still leave a low confidence of the impacts of
this wave. Winds will be generally breezy during the afternoons
across the Columbia Basin with sustained in the low teens and
gusts to near 25 miles per hour for most locations. Highs will range from
the mid 90s to mid 80s across the region. Lows will be in the low
60s to 50s. /Jdc

&&

Aviation...
18z tafs: VFR conditions expected at all taf sites through 18z
Sunday. Winds will be light.

&&

Fire weather...
several fire weather concerns. Late Sunday afternoon a cold front
will approach the region. This will push strong northerly winds
down the Okanogan Valley into the Waterville Plateau and western
Columbia Basin. Winds will increase by 5pm, but really get going
by 8pm. Gusts to 35 mph is expected with some isolated locations
across zone 684-685-687 seeing gusts to 40 mph. The Wenatchee
valley will also see gusty winds during the evening hours. The
timing of the winds in relation to the minimum humidity raises
concern. Though the relative humidity values will be increasing after 5pm, am
concerned it won't be quickly enough. In addition...with the very
dry air moving in with the cold front, have increased our Haines
to a 5 across central Washington Sunday evening and take it across
northern Washington and Idaho during the overnight hours. This dry air and
windy conditions will also create very poor relative humidity recoveries
overnight into Monday morning. The winds will continue through mid
afternoon Monday with widespread relative humidity values in the low 20s or
teens. We will continue to monitor this critical fire weather
scenario that is setting up.

&&

Preliminary point temps/pops...
Spokane 88 64 92 62 89 62 / 0 0 0 0 0 0
Coeur D'Alene 87 60 92 58 88 56 / 0 0 0 0 0 0
Pullman 86 60 92 58 89 58 / 0 0 0 0 10 10
Lewiston 94 66 100 67 96 66 / 0 0 0 0 10 10
Colville 89 57 92 53 89 54 / 0 0 0 0 0 0
Sandpoint 85 53 90 50 87 50 / 0 0 0 0 0 0
Kellogg 83 56 88 56 87 55 / 0 0 0 0 10 10
Moses Lake 93 62 97 60 93 59 / 0 0 0 0 0 0
Wenatchee 93 67 94 64 92 66 / 0 0 0 0 0 0
Omak 93 62 96 60 93 61 / 0 0 0 0 0 0

&&

Otx watches/warnings/advisories...

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