778
FXUS65 KPIH 200735
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
135 AM MDT Wed Aug 20 2025

.KEY MESSAGES...

- Weak shortwave trough today will support an increase in cloud
  cover and isolated showers/virga and dry thunderstorms, as
  otherwise warm and dry conditions will continue.

- Elevated fire weather conditions will exist today with
  afternoon RHs in the single digits/teens coupled with breezy
  winds.

- Monsoon moisture lifting north late Saturday into Sunday will
  support the return of daily shower and thunderstorm chances
  into early next week as temperatures trend cooler.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 135 AM MDT Wed Aug 20 2025

Early morning satellite imagery shows a shortwave trough
lifting northeast out of the Great Basin into eastern Idaho,
leading to an increase in cloud cover along with supporting
isolated showers and virga throughout the day. Given a very dry
environment at the surface, little to no precipitation is
expected out of any of this activity, with any isolated dry
thunderstorms expected to remain southeast of the Snake River
Plain. Activity will subside after sunset tonight, with dry
conditions back overnight into Thursday, outside of isolated
showers and storms around the Bear Lake region Thursday
afternoon. Highs today and Thursday will be a bit cooler
overall from the near record to record heat we saw yesterday,
with highs in the mid 80s to mid 90s. Winds will see a diurnal
increase each afternoon, with wind gusts peaking around 15-30
mph.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 135 AM MDT Wed Aug 20 2025

Hot and dry conditions will continue for Friday into Saturday
with highs in the mid 80s to mid 90s, as the leading edge of a
push of monsoonal moisture begins to build in late Saturday into
Sunday. As a result of this increased moisture transport into
our area, isolated showers and thunderstorms south of the Snake
River Plain will be possible Saturday afternoon and evening,
ahead of a regionwide expansion to all of eastern Idaho for
Sunday into Monday where we will see an increase to isolated to
scattered coverage. Temperatures will respond quickly to the
increased cloud cover and moisture building in, leading to
cooler temperatures early next week as highs return to the
70s/80s starting Monday. Early next week is shaping up to be the
most robust push of monsoon moisture we have seen so far this
year with widespread precipitation chances expected Sunday
through at least next Wednesday. PWAT anomalies starting Sunday
will climb to 150-200% of normal through Thursday, supporting
stronger storms that will be capable of producing heavy rain.
Any rain will certainly be much appreciated out here at our
office at Pocatello Regional Airport, as yesterday marked the
46th consecutive day of no measurable precipitation. This ties
the 7th longest stretch in recorded history since 1939. With the
GEFS/EPS ensembles showing unanimous agreement on widespread
precipitation next week, this streak looks like it will be
coming to a close as we finish out the month of August.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1000 PM MDT Tue Aug 19 2025

High pressure will bring VFR conditions through the period.
Expect some mid level clouds into tomorrow with moisture moving
in South Southwest flow aloft. Winds will gust up to around 15
to 20 kts for IDA, PIH, and SUN (and maybe DIJ) tomorrow
afternoon.

&&

.FIRE WEATHER...
Issued at 135 AM MDT Wed Aug 20 2025

Following near record to record warmth regionwide yesterday, a
shortwave trough passing overhead today will lead to an increase
in cloud cover along with supported isolated showers and virga
throughout the day. Given a very dry environment at the surface,
little to no precipitation is expected out of any of this
activity, with any isolated dry thunderstorms expected to remain
southeast of the Snake River Plain. Activity will subside after
sunset tonight, with dry conditions back overnight into
Thursday, outside of isolated showers and storms around the Bear
Lake region Thursday afternoon. Highs today and Thursday will
be a bit cooler overall from the near record to record heat we
saw yesterday, with highs in the mid 80s to mid 90s. Winds will
see a diurnal increase each afternoon, with wind gusts peaking
around 15-30 mph. Afternoon RHs will continue to be very dry in
the single digits/teens through the end of the week, however
widespread critical fire weather conditions are not expected.
The best overlap of winds/RH will be today with gusts peaking
around 15-30 mph, supporting elevated fire weather conditions.

Dry conditions will return regionwide for Friday into much of
Saturday, as the leading edge of a push of monsoonal moisture
begins to build in late Saturday into Sunday. As a result of
this increased moisture transport into our area, isolated
showers and thunderstorms south of the Snake River Plain will be
possible Saturday afternoon and evening, ahead of a regionwide
expansion to all of eastern Idaho for Sunday into Monday where
we will see an increase to isolated to scattered coverage.
Temperatures will respond quickly to the increased cloud cover
and moisture building in, leading to cooler temperatures and
higher RH early next week as highs return to the 70s/80s
starting Monday. Early next week is shaping up to be the most
robust push of monsoon moisture we have seen so far this year
with widespread precipitation chances expected Sunday through at
least next Wednesday. PWAT anomalies starting Sunday will climb
to 150-200% of normal through Thursday, supporting stronger
storms that will be capable of producing heavy rain and lead to
an increased threat of burn scar impacts associated with
training or slow moving thunderstorms.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...MacKay
LONG TERM...MacKay
AVIATION...TW
FIRE WEATHER...MacKay