Area Forecast Discussion
Issued by NWS Spokane, WA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KOTX 301140
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
440 AM PDT SUN AUG 30 2015

.SYNOPSIS...
A vigorous upper level disturbance will bring the Inland
Northwest some much needed rain today. Area wildfires will have a
good chance of a tenth to a quarter inch of rain. A cool,
occasionally breezy and showery weather pattern is expected much
of next week.

&&

.DISCUSSION...

Today and tonight...Longwave trof hanging over a good portion of
the Western US allows a wet cold front to pass through it today.
Pops remain high with such a scenario given the favorable long-
wave trof placement and a somewhat well maintained moisture feed
extending into it from the south/southwest overcoming the lee side
rain-shadow of the Cascades. 0-6km AGL winds suggest storm motion
to the northeast and east at about 25 to 35 mph today. This storm
motion is fast enough to continue to note that flash flooding on
area burn scars is not likely with today`s rainfall. The -20 to
-22 deg Celsius 500mb cold pool contained in the trof is on the
order of two standard deviations on the cols side of what would be
considered normal for this time of year, therefore a mention of
thunder seems reasonable given the resulting instability of having
this cold pool aloft. Forecast temperatures on the cool side of
normal a given due to this trof and the resulting rainfall keeping
the daytime high on the cold side while more effective radiational
cooling is likely tonight under this trof. Robust winds from the
southwest remain as well today that will decrease a bit tonight
but likely not go calm given the dynamic nature of the the above
scenario. /Pelatti

Monday through Saturday...Model agreement is pretty good between
the latest GFS and EC runs with details and run to run
consistency is very good regarding the overall concept of a
persistently troffy pattern enveloping the region through the work
week. A huge parent trough over western Canada will promote a
series of disturbances brushing or enveloping the forecast area
during the week. A well directed fetch of Pacific moisture will
probably benefit from some isentropic and orographic enhancement
into the Cascades and northern mountains on Monday. Tuesday may be
a relatively dry day with a few degrees of warming before the next
trough carves into the region with another cold front on or about
Wednesday with the actual trough lingering over the region through
Friday. This argues strongly for a period of cooler than normal
temperatures...occasional periods of showers mostly on the
mountains but with a few opportunities for basin precipitation as
well. All this will be good news for the fire fighting
efforts...but the fly in the ointment will be the propensity for
breezy and occasionally gusty conditions across the basin
especially but also on the mid-slopes and ridges of the mountains
surrounding the basin...which may hamper firefighting. Monday and
especially Wednesday look like the breeziest days...with Wednesday
in particular shaping up to be quite windy and gusty in the wake
of an early day cold front passage.

Way out on or about Saturday the models suggest a pattern shift
back to a drying and warming weak ridge rebound over the region.
/Fugazzi

&&

.AVIATION...
12Z TAFS: The next 12 or so hours will potentially be the wettest
as a wet frontal zone works its way through the area. Winds will
be gusty but considerably lesser in comparison to yesterday. Smoke
from area fires may impact TAF sites again...especially KPUW and
KLWS possibly resulting in IFR ceilings and visibilities. After
02Z Monday the expectation is less wind and an end to
precipitation and a return to mostly VFR conditions, with the
exception of areas impacted by wildfire smoke. /Pelatti

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        66  50  71  53  72  53 /  80  10  20  10  10  20
Coeur d`Alene  63  48  70  51  72  51 /  80  10  20  10  10  30
Pullman        65  48  72  51  73  49 /  60  10  10  10  10  30
Lewiston       72  53  81  57  81  58 /  70  10  10  10  10  20
Colville       68  49  67  50  73  49 /  90  10  40  20  20  40
Sandpoint      61  47  66  49  71  49 /  90  20  40  20  20  50
Kellogg        60  45  69  48  70  49 /  90  20  20  10  10  50
Moses Lake     75  53  77  55  77  53 /  80  10  10  10  10  10
Wenatchee      74  53  74  55  74  56 /  40  10  20  20  10  20
Omak           74  50  70  51  74  50 /  50  10  30  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.