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
000
FXUS66 KOTX 161047
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
247 AM PST Sat Dec 16 2017

.SYNOPSIS...
After a dry but cloudy Saturday, another weather system will bring
more snow on Sunday. A warm and wind weather system will arrive on
Tuesday into Wednesday bringing the potential for heavy mountain
snows and mix of rain and snow in the lower elevations. The
weather will then be dry and cold for the remainder of the week.

&&

.DISCUSSION...
Today through Sunday night: The last of the snow is finally
exiting the area over the Palouse and southern Panhandle this
morning. The weather for the remainder of the day should be dry
but with plenty of low clouds in most areas, which could bring a
flurry or two.

The next system moves into the region late Saturday night. After
my colossal busted forecast, my forecast confidence for Sunday is
low. It`s worth noting that the Sunday system is nothing like
yesterday`s storm. It`s more of a traditional storm for the Inland
NW, as warm air pushes over cold air. This doesn`t look like a
strong event. The favored areas will be the ID Panhandle and
northeast WA with this storm. The lower Basin will see the least
amount of precipitation, but this will probably be in the form of
a little freezing rain. Spokane and the Palouse may change from
snow to a brief rain at the end of the storm on Sunday evening.
Temperatures there will warm above freezing and stay that way
overnight into Monday. RJ


Monday through Friday: The continued active interval opens with a
very flat and dirty low amplitude ridge over Eastern Washington and
Northern Idaho. The zonal flow allows for a rain/snow shadow of
sorts extending from somewhere within the lee of the Cascade Crest
eastward across the Columbia Basin and lowlands as far east as
western portions of Spokane and Whitman counties while locations
free of the rain/snow shadow influence may get some light rain and
snow from disturbances running through the ridge. Tuesday a low
pressure system and its associated frontal features moves through
the area. Initially the warm southwest flow of moisture into the low
pressure system coupled with the low level southerly flow will allow
for a rain with high mountain snow. Temperatures will also peak on
Tuesday and the southerly winds are likely to be brisk. Wednesday
the low pressure system treks away to the south and east and drags a
front through allowing for the brisk winds to shift to the southwest
and eventually from the northwest as the longwave ridge axis sets up
off the coast. This sets up a cold and potentially drier northerly
flow which persist into Thursday and Friday. The northerly flow
appears void of significant shortwave disturbances and as such the
forecast is trended to be a generally dry and colder one so forecast
temperatures show a cooling trend after peaking on Tuesday.
/Pelatti


&&

.AVIATION...
12z TAFS: The exiting system should bring light snow to KPUW and
KLWS for only a few hours this morning. After that the TAF sites
will remain under a low IFR stratus this morning which may lift a
little later this afternoon. The exception to this will be at KEAT
which will be out of the stratus today, but it should return after
sunset.  RJ

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        29  26  34  32  37  33 /  10  20  70  40  20  60
Coeur d`Alene  30  26  34  32  38  33 /  10  20  70  70  40  80
Pullman        29  25  34  34  39  35 /  50  10  40  60  50  60
Lewiston       33  27  37  36  45  37 /  40  10  30  50  40  40
Colville       32  26  32  29  36  30 /   0  40  80  50  20  60
Sandpoint      33  26  32  30  37  31 /   0  30  90  90  40  80
Kellogg        26  23  31  30  35  32 /  30  10  70  90  70  90
Moses Lake     33  29  35  30  40  33 /  10  30  20  10  10  30
Wenatchee      34  28  33  30  39  32 /   0  20  30  10  20  30
Omak           33  28  32  29  35  30 /   0  40  50  10  20  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 4 AM PST early this morning for
     Central Panhandle Mountains-Idaho Palouse-Lewiston Area.

     Winter Weather Advisory until 7 AM PST this morning for Lewis
     and Southern Nez Perce Counties.

WA...Winter Weather Advisory until 4 AM PST early this morning for
     Lower Garfield and Asotin Counties-Washington Palouse.


&&

$$



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