Area Forecast Discussion
Issued by NWS Spokane, WA

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FXUS66 KOTX 301220
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
520 AM PDT TUE JUN 30 2015

.SYNOPSIS...The weather will be mainly dry and continued very
warm throughout the week. A couple of weak disturbances today and
again Thursday will likely stir up the winds a bit in the
afternoon. Friday looks to be the warmest day this week...with
valley highs ranging from 96 to 104.



&&

.DISCUSSION...
Red Flag Warning issued for the Kittitas Valley (Fire Weather
Zone WAZ676) for combination of gusty winds and low relative
humidity.

&&

.AVIATION...
12Z TAFS: High pressure will build in over the region. This will
promote clearing skies and VFR conditions at all TAF sites. Patchy
fog will be possible in the Northern Panhandle early this morning,
but should remain north of KCOE. Gusty NW winds will affect the
KEAT area this afternoon/evening. These NW winds may also bring a smoke
layer to the KMWH terminal from area wildfires but visibility should
remain VFR. /EK



&&

.PREV DISCUSSION... /ISSUED 222 AM PDT /

..GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR CASCADE GAP VALLEYS...

Today through Wednesday...A shortwave trough will slide across
the northern tier this afternoon/evening. This will bring isolated
showers and thunderstorms to extreme northeast Washington and the
northern panhandle of Idaho. Convective parameters (CAPE/bulk
shear) will be marginal so organized storms are not expected. The
main weather concern will be gusty winds for the Cascade gap
valleys this afternoon that will briefly overlap with minimum
relative humidity for the Kittitas Valley. Gusty winds and low RH
may briefly overlap in the Wenatchee Valley but criteria will just
barely be met, if at all. Confidence is higher for meeting
critical fire weather criteria in the Kittitas Valley. Expect
sustained winds of 15 to 20 mph with gusts of 25 to 35 mph during
the late afternoon/early evening hours. The stronger winds are
expected to develop closer to sunset when RH is starting to
increase. As the trough moves east tonight, the focus for gusty
winds will shift to the Okanogan Valley where the northerly
surface pressure gradient will strengthen. This will be less of a
fire weather concern since the stronger winds will occur during
the overnight hours when RHs are recovering.

The passing trough will act to knock down the ridge temporarily
but it should rebound quickly for Wednesday. Temperatures today
will be about the same as Monday`s readings with highs around 15
degrees above normal. Temperatures will warm slightly Wednesday
under the building ridge. A few high temperature records may in
jeopardy across the lower basin but this will not be widespread.
/Kelch

Wednesday night through Friday...The ridge of high pressure will
be assaulted once more by a fast moving...but weak and dry short
wave disturbance. This wave will once again over top the ridge and
track through southern B.C. A tightening of the pressure gradient
across the Cascades will result in increased winds through the
gaps and spilling onto the Waterville plateau ad possibly down the
Okanogan valley. The wave will also keep temperatures in check (at
least a little bit anyway), but highs will still be 15 degrees or
more above average.

Friday through Tuesday the models are showing the ridge bending
down further as a stronger wave moves through northern B.C. and
east across the divide Friday and Friday night. Meanwhile the
ridge will retrograde into the eastern Pacific and begin to
amplify. This puts the region in a dry northwesterly flow and
brings cooler temperatures to the region.

By Monday model guidance diverges enough that forecast confidence
is on the low side of average. One model wants to rebuild the
ridge just inside 130W with the northwest flow shifting to east of
the divide and keep conditions warm and dry...another model want
to dig another low south along the coast and open up the Pac NW to
a moist southwest flow and a better chance for thunderstorms.
Still another model in somewhere in between with the low closing
off over B.C. The forecast for Monday and Tuesday leans heavily
towards a warm and dry solution and we will see how things shape
up to begin the new work week. Stay tuned. Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        94  65  95  66  97  68 /   0   0   0   0   0   0
Coeur d`Alene  91  61  92  61  95  62 /   0   0   0   0   0   0
Pullman        90  56  91  56  95  59 /   0   0   0   0   0   0
Lewiston       99  67 100  67 103  69 /   0   0   0   0   0   0
Colville       95  60  96  60  99  62 /  10  10   0   0   0   0
Sandpoint      90  54  91  54  93  56 /  10   0   0   0   0   0
Kellogg        90  60  91  58  95  59 /   0   0   0   0   0   0
Moses Lake    100  65 101  66 102  67 /   0   0   0   0   0   0
Wenatchee      99  69 100  73 104  73 /   0   0   0   0   0   0
Omak           98  61  99  63 101  63 /   0   0   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Red Flag Warning from 3 PM this afternoon to 8 PM PDT this
     evening for East Washington South Central Cascade Valleys
     (Zone 676).

&&

$$



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