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Area forecast discussion 
National Weather Service Spokane Washington
429 am PDT Thu Aug 25 2016

Synopsis...
light northerly winds will continue today and tonight with
warm temperatures. A few mountain showers and thunderstorms are
possible near the Canadian border later today, otherwise expect
dry weather. Area wildfires have not produced as much smoke as in
the last couple of days, although these smaller smoke plumes will
be pushed into the Columbia Basin and the Palouse. Winds will
switch Friday afternoon with southwest winds, and this would
change the smoke plume spread. A strong cold front is expected to
bring gusty west winds Saturday and heighten wildfire concerns
once again. Seasonal temperatures return next week with an
increase chance for showers across the northern mountains.

&&

Discussion...
today through friday: a fairly dry northerly flow aloft will be over
the inland northwest. Temperatures will be moderating, creeping above
normal for today and Friday with widespread 80s and a few lower
90s. A weak disturbance will be dropping down through the Canadian
rockies today. The bulk of the energy and moisture will head
toward northwest Montana, although there is a chance that it will clip
the northern mountains of north Idaho and extreme northeast
Washington this afternoon. Low level instability increases this
afternoon in these areas, but a weak cap does exist. Any activity
that develops in southeast British Columbia has a good chance of tracking
southward and across the border. Will keep a chance of showers in
for these northern mountains late this afternoon and early
evening. There is the potential of thunderstorms embedded in the
showers. The main threat from the stronger storms would be gusty
outflow winds as the cloud bases will be quite high and measurable
precipitation will be lacking except for the higher mountains.
With a surface high pressure area over Oregon, winds will remain
out of the north to northeast today and tonight, being enhanced in
the Okanogan Valley and north Idaho as stronger gusts get mixed to
the surface. Areas of smoke from the local wildfires will continue
to follow similar paths as experienced on Wednesday, spreading
southwest from their source regions. On Friday, subtle changes
occur at the surface with the weakening of the surface high and
the thermally-induced low pressure trough skips across the
Cascades into the Columbia Basin. This feature will lead to a low
level wind shift with west to southwest winds by Friday afternoon.
Speeds will be light, but the change in direction will effect the
area wildfires and switch the spread of the smoke to areas,
pushing it more to the northeast. /Rfox.

Friday night through Saturday night...some changes showing up in
the models as the disturbance moving through b.C is now a bit
stronger. Model guidance is starting to show some timing
differences as well. At this time will go with the cold front
dropping into the region Saturday afternoon and sagging through
the northern zones around or just after 00z then stalling along
the Oregon border on Sunday.

***Breezy to windy with low relative humidity Saturday afternoon
and Saturday night***

So what does this mean for the weather. Winds will increase through
the day on Saturday with sustained southwest winds 10-20 mph with
gusts 20-30 mph possible for the Blue Mountains, the Camas
Prairie, the Columbia Basin, both the Washington and Idaho Palouse
and north up into the Spokane-Coeur D'Alene area. Relative
humidity will remain very dry and between 15-25 percent. Winds
will likely last through the night with only modest relative
humidity recovery. This combination will result in fire weather
concerns for ongoing fires and any new starts across the region.
As mentioned earlier there are some timing issues and would like
to hold off on issuing any highlights until I see one more model
package.

While the cold front will be packing some decent forcing,
and pwat's increase to well above normal the moisture is coming
in well above 700mb. While confidence isn't very high in
measurable precipitation, showers and isolated thunderstorms will
be kept in the forecast for the northern mountains. Temperatures
on Saturday will be the warmest of the week with highs a few
degrees above normal, the temperatures will drop 4-7 degrees on
Sunday behind the cold front. Winds will remain elevated on
Sunday but 5-10 mph less than on Saturday.

Monday through Thursday...all guidance is showing the pattern
changing to a long wave trough early next week, but that is about
all they agree on. This forecast leans in the favor of a more
progressive pattern which will result in a chance for partly
cloudy conditions with isolated to scattered mountain showers most
afternoons. Temperatures will hover within a few degrees either
side of normal with breezy basin winds at times. Tobin

&&

Aviation...
12z tafs: smoke in the area will be patchy at best. It may reach
the kpuw area this morning, but confidence is marginal. Otherwise
expect mostly clear VFR skies under light winds. /Rfox.

&&

Preliminary point temps/pops...
Spokane 83 57 84 59 86 59 / 0 0 0 0 10 10
Coeur D'Alene 82 53 83 55 84 56 / 0 0 0 0 10 10
Pullman 83 48 85 53 86 53 / 0 0 0 0 0 10
Lewiston 89 57 90 61 93 62 / 0 0 0 0 0 10
Colville 87 51 87 53 87 53 / 0 0 0 10 10 10
Sandpoint 80 49 80 50 82 52 / 10 10 10 0 10 10
Kellogg 79 49 80 52 81 54 / 0 0 10 0 10 10
Moses Lake 91 55 91 58 91 57 / 0 0 0 0 10 10
Wenatchee 88 62 89 65 87 62 / 0 0 0 0 10 10
Omak 90 58 89 59 89 56 / 0 0 0 0 10 10

&&

Otx watches/warnings/advisories...
Idaho...none.
Washington...none.
&&

$$

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