Wildfire in Idaho, September 1 to 30, 2022

Area Forecast Discussion
National Weather Service Pocatello ID
158 PM MDT Wed Aug 31 2022

.SHORT TERM...Tonight through Thursday night.

A ridge of high pressure is centered over the central Great Basin
while a weak shortwave trough is moving northward over the top of
this ridge. This shortwave may trigger a few isolated virga showers
across the central mountains this afternoon. Probably not
significant enough to mention in the forecast. Although a rogue wind
gust of 30-35 mph is possible. Otherwise hot temperatures have
arrived and will persist for the next several days with heat
advisories in effect through the weekend. As the trough passes over
the top of the ridge on Thursday, we will see some breezy conditions
develop with wind gusts of 20-25 mph possible across most of the
area. With the trough beating down the ridge slightly, we could see
temperatures receded by a couple degrees, but not really enough to
justify dropping the heat advisory just to end up reissuing by the
weekend (more on this in the extended discussion). Also potentially
noteworthy, is that we may see some smoke and haze work into east
Idaho from fires in the middle part of the state Thursday afternoon
as our winds shift to the west northwest.

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.LONG TERM...(Friday - next Wednesday)...
There remains very high confidence in near-record to record heat
across all of eastern Idaho throughout the holiday weekend and into
the first half of next week. At the moment, heat Advisories continue
through Sunday and will certainly need to get extended into Labor
Day and likely into Tue and maybe Wednesday eventually as well.
Saturday through Monday looks to be the peak period for afternoon
heating with increasing confidence in temperatures nearing or
surpassing 100 from Pocatello south and west into the Magic Valley.
GFS/ECMWF ensemble means are sitting around 99 to 100 at KPIH for
each day during the aforementioned time period. As one would expect
with this type of weather pattern, chances for PoPs during any day
appear slim to none and winds should not be much of an issue either,
generally 10-15 mph on any given day. The main forecast message
remains is that it will be unusually hot for early September across
eastern Idaho and residents and visitors to the area are urged to
practice heat safety. Just beyond the current forecast period,
global models are hinting at perhaps a major pattern shift with a
strong low/trough coming out of the Gulf of Alaska or Western
Canada. Still plenty of time for this to change, but if it pans out,
this would likely result in an abrupt end to the heat followed by
much cooler than normal temps. But considering this is a good 8-9
days out, a lot can still change. Nevertheless, it is something to
watch for those who are rooting for an end to the summer heat.
McKaughan

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.AVIATION...VFR to prevail with light winds and mostly sunny
skies expected through the forecast period. Aside from some
occasional high clouds streaking across the region with winds 10
kts or less. There is a very isolated chance for a stray shower
near KBYI and KSUN but given the dry air aloft, it likely would
not translate to precip at the surface but could create for some
turbulence in the skies near the airfield. Winds will be light
overnight but will increase a bit tomorrow, mainly in the
afternoon, to around 15 kts. McKaughan

&&

.FIRE WEATHER...An isolated virga shower is possible across portions
of the Salmon-Challis this afternoon. Otherwise, hot and dry weather
will continue through the next several days. Noncritical wind gusts
of 20-25 mph is possible. Minimum humidities in the single digits to
mid teens is likely over the next several days as well as Haines
values of 5 and 6. Another system will work over the ridge on
Saturday which will produce more gusty winds, possibly reaching
critical levels.

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&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until midnight MDT Sunday night for IDZ051>059-075.

&&