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Area forecast discussion
National Weather Service Spokane Washington
420 am PDT Tue Jul 25 2017

it will be warm and dry for much of the week, except for a slight
chance of mountain thunderstorms in the southern Panhandle late
Wednesday and Thursday afternoon. A marine push on Thursday will
bring breezy and slightly cooler conditions for the end of the
week before the heat returns for the weekend.


today through Wednesday night: dry and warmer weather can be
expected. A weak upper trough over the region will flatten out
into northwest flow as a ridge builds in. Surface high pressure
over the Canadian rockies and British Columbia will support the north to
northeast winds across the northern valleys this morning into
midday. In fact a return of gusty winds will be found in the
Okanogan Valley this morning into early afternoon along with low
humidities, although speeds should be quite a bit less than the
last two days. Expect gusty northeast winds over north Idaho, from
Sandpoint to Coeur D'Alene, this morning as well. Pressure
gradients relax this afternoon with lighter winds into the evening
and into Wednesday. Plenty of dry air will persist under this
westerly flow pattern. It's the remnants of the high level monsoon
moisture creeping in from the south that will move across
southeast Washington and the southern Panhandle today and
Wednesday. By Wednesday, the moisture layer deepens slightly and
mid level instability brushes extreme southeast Washington into
the southern Panhandle. This would support a small chance of
thunderstorms primarily Wednesday evening. Dry weather will
persist elsewhere along with some patchy smoke from area fires.
Temperatures will climb a few degrees each day with a slow warming
trend. /Rfox.

Thursday through monday: models continue to vary a bit on the low
off the California coast. They're now a little slower with it, bringing it
onshore on Wednesday as the Gulf of Alaska sends another wave into
the pac northwest. These 2 waves come into phase with each other on
Thursday afternoon. Normally this would be a good thunderstorm
pattern, but the models all agree that we're just too dry to
initiate much convection. The best chance for showers continues to
be in southeast Washington and the southern Panhandle.

The other affect of this wave phasing will be a weak marine push
for our area. Thursday will be a bit breezy in the afternoon.
Temperatures could cool a few degrees, especially in the Cascades.
The winds probably won't be strong enough to qualify for a red
flag warning, but it will still be a critical fire weather day.

Temperatures on Friday will cool a few more degrees. After that,
the cycle repeats itself as the western US ridge of high pressure
amplifies once again, bring a return to hotter temperatures for
the weekend. Rj


12z tafs: expect VFR conditions at the taf sites under the dry
westerly flow aloft. Some high cirrus will thin out across the
eastern sites this morning, but may return again tonight. Winds
will be lighter than those yesterday. Anticipate north to
northeast breezes through 18z, then becoming light and variable
into the evening hours. Areas of smoke from regional wildfires
may occasional drift around some airports but the main threat will
be in the northern valleys, north of the main taf sites. /Rfox.


Preliminary point temps/pops...
Spokane 89 61 92 63 91 62 / 0 0 0 0 10 10
Coeur D'Alene 88 56 91 58 90 57 / 0 0 0 10 10 10
Pullman 89 52 91 58 89 58 / 0 0 10 10 10 10
Lewiston 96 61 97 66 97 65 / 0 0 10 10 20 20
Colville 91 53 94 57 93 55 / 0 0 0 0 10 10
Sandpoint 88 49 89 51 89 51 / 0 0 0 10 10 10
Kellogg 86 53 89 56 88 56 / 0 0 0 10 10 10
Moses Lake 95 56 97 61 95 58 / 0 0 0 0 0 0
Wenatchee 92 66 95 67 92 63 / 0 0 0 0 0 0
Omak 94 58 97 62 96 60 / 0 0 0 0 0 0


Otx watches/warnings/advisories...

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