829
FXUS65 KPIH 070754
AFDPIH
Area Forecast Discussion
National Weather Service Pocatello ID
154 AM MDT Mon Jul 7 2025
.KEY MESSAGES...
- Hot weather for the first half of the week.
- Cold front arrives Wednesday bringing cooler weather for late
week.
- Potential red flag conditions for wind and humidity Wednesday.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 149 AM MDT Mon Jul 7 2025
Ridge of high pressure will amplify over Central and East Idaho on
Monday. This will produce dry and hot conditions for Monday and
Tuesday. Many of the lower elevations will see highs in the upper
80s to around 90 today. On Tuesday, these same areas will see highs
in the low to mid 90s. Looking at dry conditions today. Although on
Tuesday, a weak shortwave trough will work through the greater
ridge. Models are showing some isolated dry thunderstorms across the
high country Tuesday afternoon. The better chances are across the
central mountains where the ridge is not as strong. Some virga bombs
are possible Tuesday afternoon, with gusty outflow winds likely in
and around thunderstorms.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 149 AM MDT Mon Jul 7 2025
As a H5 ridge axis shifts east on Wednesday, a Pacific trough will
move onshore to the PacNW and track east into southeast Idaho. This
trough will support an uptick in winds for Wednesday and Thursday
and a 5-15% chance of virga/showers and wet/dry thunderstorms
Wednesday through Friday, supported additionally by a secondary
reinforcing trough passing north through Montana Thursday into
Friday. Given a good deal of dry air to overcome at the surface and
the isolated nature of any showers and convection, our latest
forecast keeps conditions mostly dry with this trough passage with
best chances remaining confined to the mountains. Gusty winds will
however be possible associated with any activity given a very dry
airmass at the surface remaining conducive for gusty outflow winds.
Winds on Wednesday and Thursday will peak synoptically each
afternoon around 15-30 mph with gusts to around 25-45 mph. Behind a
mostly dry cold frontal passage late Wednesday into early Thursday,
temperatures will drop about 5-10 degrees for Thursday and Friday as
isolated showers and storms shift further north and east associated
with that secondary trough passing through Montana. Following this
series of troughs to finish out the work week, ensemble model
guidance continues to support the resurgence of high pressure over
southeast Idaho, allowing for warming temperatures and dry
conditions back for the weekend into early next week.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1002 PM MDT Sun Jul 6 2025
VFR weather with a few mid level clouds around for the next 24
hours. For SUN, there will be a window from very late morning
through mid afternoon where southerly winds COULD be strong
enough to impact air traffic.
&&
.FIRE WEATHER...
Issued at 149 AM MDT Mon Jul 7 2025
Under the increasing influence of high pressure early this week,
conditions will remain hot and dry as temperatures see a warming
trend with lighter winds and mostly clear skies. The warmest
temperatures are expected Monday through Wednesday, with highs
reaching the upper 80s to upper 90s in the valleys. Given a very dry
airmass in place, afternoon humidities will drop to the teens/20s
each afternoon, dropping even further for Tuesday and Wednesday to
the single digits and teens. Increased fire weather concerns are
expected for Wednesday as high confidence supports a Pacific trough
and mostly dry cold front building in late Wednesday into Thursday,
bringing the return of breezy winds and isolated wet and dry showers
and thunderstorms. Due to a combination of elevated winds and low
relative humidity, near critical to critical fire weather conditions
are expected on Wednesday. Wind gusts look to peak around 25-45 mph
both Wednesday and Thursday. As a result, we will likely be
coordinating with regional partners for any fire weather headlines
midweek, particularly Wednesday. As that trough and front passes
east on Thursday, a secondary reinforcing trough passing through
Montana through Friday will help bring temperatures down and support
a slight increase in RHs, albeit still supporting elevated fire
weather conditions Thursday. With that secondary trough departing
east on Friday, isolated showers and storms will shift to being
along the Wyoming border region, with hot and dry conditions
building back in for the weekend into early next week.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...13
LONG TERM...MacKay
AVIATION...Keyes
FIRE WEATHER...MacKay
