283 
FXUS66 KOTX 230941
AFDOTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
241 AM PDT Sun Jun 23 2013

.SYNOPSIS...
The weather today will be warm and dry with just a few mountain
showers. Clouds will increase in the afternoon as another Pacific
weather system moves into the area. Cool and wet weather will
persist through mid week. The weather pattern will then change
dramatically with much warmer and drier weather for the end of the
week. Temperatures by next Saturday could be the hottest of the
year so far.


&&

.DISCUSSION...
Today through Monday...The next Pacific weather system to affect the 
Inland Northwest is on our doorstep. Satellite water vapor imagery 
shows the stream of moisture ahead of the trough pushing into the 
region. The trough has a tap into a nice plume of moisture with Pwat 
content of an inch to an inch and a half. This translates locally to 
125 to 175 percent of normal. The moisture is presenting itself as a 
mid level cloud shield over the western half of the forecast area. 
Regional radar mosaic shows some light returns over western and 
north central Oregon that will spread to the Cascades and possibly 
into south central Washington by daybreak. We also have some 
isolated shower activity over extreme NE WA, courtesy of the very 
slowly departing low over central Alberta. This will likely persist 
through mid-morning while moving slowly east into North Idaho. 

Today we will start the transition to a much more active weather 
pattern as a couple of shortwave impulses affect the region. The 
first wave will arrive as an occluded front that will bring a few 
showers to the higher elevations this afternoon but the main surge 
of moisture will come this evening and into the overnight hours. The 
timing of the front will keep thunder threat quite low. The second 
wave will arrive during the day Monday as the negatively tilted 
trough axis sweeps through the Inland Northwest. This is a favorable 
pattern for thunder across the area, especially considering the 
timing and that there may be some breaks in the cloud cover behind 
the first wave that will allow more surface heating. 

Without taking any heavy rain from thunderstorms into
consideration, the general range of qpf through Monday night will
be from a tenth or two in the deep basin...to a third an inch over
the rising terrain of the east basin...to a half inch in the
valleys north and east of the basin...and three quarters of an
inch or more in the mountains. This precipitation is likely to
impact small stream levels later in the week and will need to be
monitored closely.

High temperatures today will be in the mid 70s to low 80s, then will 
cool about 10 degrees or so Monday under extensive cloud cover and 
precipitation. /Kelch 

Monday night through Wednesday: Models are in good agreement of
pieces of energy from the parent low sitting in the eastern
Pacific ejecting and moving through the Inland Northwest. One will
move through Tuesday and another Wednesday. Chance of showers will
prevail in the forecast. The stronger of the waves is Tuesday
where there will be enough instability, moisture from recent
rains, and the wave moving through to provide a slight chance of
thunderstorms to most locations. Wed the chance of showers will
continue as the last wave moves through the area. Have lowered max
temperatures a few degrees. Think the fairly extensive cloud cover
will keep temps 5-10 degrees below average Tuesday. A 3-6 degree
temperature increase is expected Wed, but sadly will still be below
average. Min temps will be around average for this time of the
year.

Thursday through Sunday: The models have come more in line with
the idea of a ridge building over the intermountain west starting
Thursday. Have kept with the previous forecast and have no mention
of precipitation in the extended forecast. Models do disagree
starting late Friday afternoon with some moisture moving in and
some possible showers developing. Right now I am siding with the
more persistent GFS that we have been following the last few days.
The GFS would suggest we will be dry through at least early
Saturday and then the possibility of the ridge moving slightly to
the east allowing for a more moist southwest flow that would be
conducive of showers and thunderstorms in the late afternoon/evening
hours. But for now have not made any changes. Models will likely
continue to flip flop back and forth over the placement of the
closed low in the eastern Pacific and how close it will move to
the west coast to bring a weather feature through the area.
Temperatures Thursday will be around average for this time of the
year. By Friday they warm to above average readings. As to how
warm we will get, there are still some uncertainties. 00Z runs of
the GFS and ECMWF have come in a few degrees cooler at 850 mb.
Have lowered temps a degree or two for Saturday and went a bit
lower than that for Sunday. But, temperatures will still be about
10 degrees above average for this time of the year. /Nisbet

&&

.AVIATION...
00Z TAFS: The skies are beginning to clear over the region,
allowing for afternoon/early evening showers to develop over the
higher terrain of northern Washington into the Idaho panhandle.
These showers, however, will likely not affect any of the TAF
sites. Otherwise, a quiet night is in store site-wide, before
clouds begin to increase from the southwest on Sunday. Right now,
any shower or possible thunderstorm activity at any site will
occur after the 24/00z time frame. ty



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        76  55  68  53  68  53 /   0  60  70  70  50  40 
Coeur d'Alene  76  55  68  54  68  53 /   0  60  80  70  60  40 
Pullman        76  52  68  52  68  52 /   0  60  70  60  50  40 
Lewiston       84  59  75  56  76  57 /   0  60  70  70  50  50 
Colville       80  54  73  55  72  52 /  10  60  90  70  60  50 
Sandpoint      76  53  69  54  68  50 /  20  60  90  80  70  40 
Kellogg        74  53  65  52  66  51 /  10  50  80  80  60  40 
Moses Lake     80  58  74  56  75  56 /  10  60  60  40  20  10 
Wenatchee      77  60  74  56  73  56 /  20  60  60  40  20  10 
Omak           81  58  74  57  73  53 /  10  70  70  50  40  20 

&&

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

$$