331
FXUS65 KPIH 101942
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
142 PM MDT Thu Sep 10 2026

.KEY MESSAGES...

- Breezy and dry afternoon surface conditions continue to bring
  Red Flag conditions to portions of East Idaho today, and
  potentially Friday as well.

- Light showers possible overnight into Friday morning across
  the eastern highlands, then a higher potential for
  precipitation Saturday night into Sunday.

- Cooling trend expected into the weekend, with coolest
  temperatures expected Sunday.

&&

.DISCUSSION...
Issued at 142 PM MDT Thu Sep 10 2026

Satellite imagery shows broad but shallow upper trough across
Western Canada this afternoon, with pair of shortwaves across
the PacNW. Moisture spreading from Oregon into Idaho today,
increasing clouds across the region. Upstream radar shows weak
showers across northern Nevada, and today`s High-res CAMs bring
threat of weak showers across the region this evening and
overnight. Surface humidities are very dry, so believe threat
for actual precipitation is low until lower overnight
temperatures and deeper moisture can improve the potential.
Instability is unimpressive, so no thunderstorm threat expected.
Even at that, precipitation should mainly be limited to
portions of the eastern highlands, and amounts will remain
light. Winds today are struggling to develop, but HRRR still
pinpointing a later afternoon into evening peak for speeds.
Similar wind conditions are expected for tomorrow, absent the
precipitation, along with slightly cooler temperatures.

Deeper shortwave associated with the broad upper low shifts into
Idaho Saturday, bringing an increased chance of precipitation
Saturday night into Sunday, mainly for northern zones across the
central mountains and Divide. Temperatures cool significantly
into Sunday with highs generally expected to range in the upper
60s to lower 70s. Headed into next work week, there are timing
and amplitude differences between operational GFS and ECMWF runs
this morning. Ensembles and ensemble clusters maintain a broad
trough across the western US, trending toward a split flow
pattern towards the latter half of the week, leading to a fair
amount of uncertainty toward temperature and precipitation
trends throughout the week.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1230 PM MDT Thu Sep 10 2026

VFR conditions expected through the period. Breezy winds have
been slow to develop today but should begin to ramp up in
intensity over the next hour or so. Winds of 10-15 kts with
gusts of 20-25 kts are expected. Mid and high level clouds will
also be on the increase for the evening and overnight hours.
Hi-res CAMs show at least some low-end precip chance as well
later tonight. For continuity, kept VCSH in but would expect
most of the precip, if any, to be in the form of virga so
wouldn`t expect much impact if they do transpire. Should see
some clearing around daybreak tomorrow with another breezy day
likely Friday afternoon with similar wind speeds to today.

&&

.FIRE WEATHER...
Issued at 1230 PM MDT Thu Sep 10 2026

An upper level trough moving southward, but staying in Canada,
will bring moderate to strong wind for today through Sat,
mainly in the afternoon, then a closed low moving in from the
west will punch up the wind even stronger on Sun. So overall it
will be a breezy to windy four days ahead.

This will combine with very low humidity today, and possibly
tomorrow, as humidity is expected in some areas to sink below
15 percent. Red Flag Warning continues for Zone 410 today with
conditions looking very similar to Friday. Opted to hold off on
another issuance for tomorrow to see how conditions transpire
today and the next shift will need to decide if an additional
one will be needed for Friday.

Over the weekend, the temperatures will cool and humidity spikes
upward as showers and thunderstorms arrive on account of this
closed low. Do not expect any critical fire weather conditions
over the weekend as thunderstorm activity should be isolated in
coverage.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 8 PM MDT this evening for IDZ410.

&&

$$

DISCUSSION...DMH
AVIATION...McKaughan
FIRE WEATHER...McKaughan