801
FXUS65 KPIH 260121
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
721 PM MDT Thu Jun 25 2026

.KEY MESSAGES...

- Showers and thunderstorms will continue to increase, peaking
  over the weekend

- Gusty winds expected even outside of where thunderstorm gusts
  develop

- Cooler temperatures over the weekend with some light, wet snow
  at mid and upper elevations

&&

.UPDATE...
Issued at 719 PM MDT Thu Jun 25 2026

The RED FLAG WARNING that was in effect for Fire Weather Zone
413 until midnight tonight has been cancelled. Isolated
thunderstorm activity will continue for the next few hours, but
has dropped below the "scattered" activity needed to meet RFW
criteria.

&&

.DISCUSSION...
Issued at 1234 PM MDT Thu Jun 25 2026

More showers and thunderstorms are coming tonight and tomorrow,
ahead the main low impact the region through Monday. We are
still expecting an uptick through the rest of the afternoon,
with an even bigger uptick overnight in the central mountains.
There is a 30-50% chance for gusts over 35 mph, with peak gusts
of 45-55 mph possible.  On Friday, we will see development
spreading east through the day. It appears a more organized band
develops over the central through tomorrow morning and
eventually across the rest of the area with the cold front. The
front likely will not clear the state until toward sunrise
Saturday. The front will kick up winds tomorrow across portions
of the Magic Valley, Snake Plain, and highlands along the
Montana border. Gusts up to 50 mph are possible in this
corridor, outside of any influence of showers or storms. We will
issue a WIND ADVISORY for the entirety of the Snake Plain and
north to the Montana border west of I-15. Circling back to
precipitation through tomorrow evening, outside of the central
mountains rainfall will be minimal. Up to 0.25" with locally
higher amounts are possible.

For Saturday through Monday, showers and thunderstorms will
increase as the low drops across the state, finally swinging
north into Montana Monday...which is a bit slower that previous
forecasts. With the track of the low, higher amounts of
precipitation will be across the central mountains and eastern
highlands. Through Sunday evening, for the Snake Plain, Magic
Valley, and South Hills/Albion Mountains, we will see anywhere
from a few hundredths to around 0.20". For the southeast
highlands, we are looking at 0.20-0.60". For the rest of central
and eastern Idaho, look for 0.40" to around 1.0". With the core
of the low passing over the central mountains, this will help
drive snow levels down to around 8000-10000ft and likely driven
down to 6500-7500ft in some spots due to heavier precipitation.
We will see light, wet snow generally above 8500ft with
occasional brief accumulation down to 6500ft. This along with
cooler temperatures will make it pretty chilly for anyone
trekking into the backcountry. Highs over the weekend will be in
the 50s and 60s for valley locations, with highest elevations
running in the low 30s to near 50. Overnight lows will be down
into the 20s and 30s, with warmer ares dropping to near 40,
which means there will be some pockets of frost or freeze
conditions coming. Lighter amounts of precipitation will
continue into Monday before the low pulls away from the state.
We do dry out through the middle of next week, in terms of
humidity at least, along with warmer temperatures. Once again,
we will be dealing with weaker lows skirting through the
area...which may produce virga/light rain and thunderstorms on
occasion.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 522 PM MDT Thu Jun 25 2026

Radar is looking very empty around our TAF sites this evening, so
have taken out VCSH and PROB30s at all sites for the rest of this
evening and into early tonight. It remains a bit breezy around PIH
and IDA with winds around 15-20kts, but winds at all sites will
diminish overnight. VFR conditions are expected for the bulk of this
forecast period as we look to stay mostly dry now with no impacts to
VIS or CIGs. Shower and thunderstorm chances increase again Friday
afternoon, so have added VCSH and PROB30 groups in at most sites.
Showers could start as early as 15Z at SUN, though it seems that
CAMs may be a bit over zealous. Thunder/lightning looks a bit
limited tomorrow, so will see what next model runs bring.

&&

.FIRE WEATHER...
Issued at 1234 PM MDT Thu Jun 25 2026

We are watching for more showers and thunderstorms developing
this afternoon. Coverage remains isolated to scattered,
although it will be interesting to see if the more widespread
rain and thunderstorms this morning keeps things at bay. We will
maintain the RED FLAG WARNING through this evening across Zone
413 as there is some potential for scattered storms to
redevelop. There is a 30-50% chance of gusts over 35 mph with
peak gusts of 45-55 mph possible. Overnight and Friday morning,
we will an area of light rain/virga developing across the
central mountains extending east along the Montana border toward
Island Park. We will see rain and thunderstorms spreading east
tomorrow afternoon and evening. Coverage will be isolated to
scattered, along with an increasing potential for wetting rains,
although the latter will only be across the central mountains.
Scattered coverage is expected across the central mountains and
Zone 411 along the Montana border, with isolated elsewhere (even
if we get a slight uptick along the cold front). After
coordinating will local fuels and fire officials, we will issue
a RED FLAG WARNING for Zone 422 tomorrow afternoon and evening.
Other areas where we meet coverage thresholds, fuels are less
critical with nothing warranting a headline. Winds overall will
increase across the area ahead of the front. Gusts of 30-50 mph
are possible, strongest across Zones 410, 411, 425, and 476.
Higher gusts are possible when adding any impacts from showers
and storms. Humidity values make a huge jump and will be well
above the 15% threshold. That said, if conditions align due to
wind and/or lightning...starts or existing fire activity could
spread. We may need to re- evaluate tonight or first thing
tomorrow on the need to expand coverage for any warnings.

Much cooler weather is coming through Monday, with coldest
conditions Saturday through Sunday night. The period of greatest
precipitation is still through Sunday evening, and with colder
temperatures this down include some light, wet snow mainly above
8500ft...although we could see it briefly drop lower than that.
The main area of concern for this will be the central mountains.
During this period, the Snake Plain (410), Magic Valley (425),
and South Hills/Albion Mountains (427), will see anywhere from
a few hundredths to 0.20". For the southeast highlands (413),
we are looking at 0.20-0.60". For the rest of central and
eastern Idaho (411, 422, 475, and 476), look for 0.40" to
around 1.0". With cooler temperatures and wetting rains coming,
we do not anticipate any need for warnings over the weekend.
Even with continued breezy conditions expected, any area that
see gusts meeting critical fire condition threshold should be
countered by much higher humidity. Light precipitation lingers
on Monday before the low pulls into Montana. Warmer and drier
conditions, at least in terms of humidity, will return by the
middle of next week. Similar to what we have been seeing this
week, there are weaker systems skirting through with limited
moisture. This may set us up for another period of virga/light
sprinkles, and a few thunderstorms.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from noon to 9 PM MDT Friday for IDZ052>054-067.
Red Flag Warning from noon Friday to midnight MDT Friday night
for IDZ422.

&&

$$

UPDATE...AMM
DISCUSSION...Keyes
AVIATION...AMM
FIRE WEATHER...Keyes