000
FXUS66 KOTX 170053
AFDOTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
553 PM PDT Thu May 16 2013

.SYNOPSIS...
A spring time progressive weather pattern will continue through
the weekend featuring seasonably mild conditions and occasional
weak storm systems bearing scattered showers and a few
thunderstorms. The next week will begin manly dry and mild...but
there is increasing confidence that a wet and cool period will
envelop the region by mid-week.


&&

.DISCUSSION...
Forecast updated to trim down POPs over the southeastern portion
of the forecast area and expand isolated rain showers a bit
further south from the northern mountains into the northern
portions of the Upper Columbia Basin, Waterville Plateau and into
the northern portions of the Moses Lake Area. Best instability
with slightly cooler 500 mb temps of -20 to -22 C are northwest of
a line from Moses Lake to Sandpoint. This is the part of the
region that is seeing the best shower activity and colder cloud
top temperatures. I trimmed back our thunderstorm chances away
from the Central Panhandle Mountains this evening, but did leave a
slight chance for some thunderstorms over the higher terrain in
the Northern Panhandle westward over into the Okanogan Highlands
through about 800 PM this evening. Cloud top temps are getting
down to below -20 C, which is the bottom range for getting any
kind of charge separation for lightning. If we do see any
lightning this evening, it will likely only be a strike or two.
Chances of showers will diminish rapidly after sunset as these
showers are being fed from heating early this afternoon. /SVH

&&

.AVIATION...
00Z TAFS: A moist and weakly unstable air mass will reside over
the region through the TAF period. There is little in the way of
upper level dynamic support...thus clouds and showers will be
mainly driven by orographic influences and daytime heating. this
evening scattered mainly mountain showers will dissipate after
02Z-03Z followed by a quiet night with clearing skies. Patchy fog
is possible from 12Z to 18Z in northern river valleys. Scattered
afternoon showers will return on Friday with a small chance of
thunderstorms mainly over mountains. A weak disturbance aloft on
Friday may allow scattered showers to form over the Columbia Basin
after 20Z...but ceilings will likely remain VFR at all TAF sites.
/MJF


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        47  69  48  65  44  65 /  20  20  20  40  20  20
Coeur d`Alene  44  68  47  64  43  63 /  20  30  20  40  30  30
Pullman        44  67  47  63  41  62 /  10  30  20  20  20  10
Lewiston       50  73  52  70  48  68 /  10  20  20  20  20  20
Colville       42  74  47  70  44  72 /  30  30  30  50  50  20
Sandpoint      41  68  46  65  43  63 /  20  40  30  40  40  30
Kellogg        45  65  48  61  44  58 /  20  40  30  40  30  30
Moses Lake     48  78  51  72  47  75 /  10  10  10  10  10  10
Wenatchee      49  74  52  67  48  70 /  20  20  10  10  10  10
Omak           44  74  47  71  43  72 /  20  20  20  40  30  10

&&

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

$$