Thatcher, Idaho Weather Forecast Discussion

166
FXUS65 KPIH 220405
AFDPIH
Area Forecast Discussion
National Weather Service Pocatello ID
1005 PM MDT Sun Sep 21 2025
.KEY MESSAGES...
- Showers and thunderstorms continue through tomorrow
- Moderate to heavy rainfall is possible along with gusty winds
- Warmer temperatures return starting Tuesday
&&
.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 119 PM MDT Sun Sep 21 2025
Our main area of low pressure along with locally heavier
rainfall and storms continues to shift into western Wyoming
this afternoon. In its wake, more showers and storms are
developing as sunshine is producing enough instability to kick
things off. Within the main area moving into Wyoming and any
stronger storms elsewhere, moderate to locally heavy rain is
possible. There is a 30-70% chance of wind gusts over 35 mph
today, with peak gusts POSSIBLY hitting 45-50 mph. The best
chance of stronger winds is across the south and in the central
mountains. This secondary area of showers and storms actually
will consolidate into a more widespread area of rain with
embedded thunderstorms tonight east of I-15, as a stronger area
of low pressure develops as it drops southeast across the
Divide. That band quickly into Wyoming tomorrow morning, with
some lingering showers and a possible thunderstorm across the
eastern and southeast highlands. By tomorrow night, things
continue to clear out. Cooler temperatures are on tap for Monday
and Monday night. The potential for warmer spots to top out
above 70 is pretty slim for highs. Tomorrow night, colder spots
dip into the 20s and 30s. If trends continue, a FROST ADVISORY
is not out of the question for the upper end of the Snake Plain.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 119 PM MDT Sun Sep 21 2025
We should see a mostly dry stretch of weather heading into next
weekend. The models are struggling on what to do with another
low as the ridge breaks down over the western U.S. The ECMWF
keeps it farther south and brings little moisture, even in the
form of clouds, our way later in the week. The GFS remains
steadfast with a farther north track, which could gives us a lot
more clouds and some possibility for light precipitation. Our
Blend of Models continues to dry things out, or at least drop
the chance of any moisture falling closer to 10%. Warmer
temperatures will be back, especially if we can keep clouds out
of here. The potential for highs starting with an "8" is
increasing toward mid to late week.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1005 PM MDT Sun Sep 21 2025
The better organized storms are beginning to move east.
Models are still indicating some isolated convection during the
overnight hours. So will continue to mention VC wording at many TAF
sites. Expect clearing during the day on Monday. NAM is trying to
develop some isolated showers during the afternoon that could affect
IDA/DIJ, but its not supported by other models. So will continue
with a SCT wording with no weather for now.
&&
.FIRE WEATHER...
Issued at 119 PM MDT Sun Sep 21 2025
Area of showers moving through the East Idaho district early this
afternoon will give way to more showers and thunderstorms.
Precipitation continues overnight as frontal boundary moves through
the state, and can`t completely rule out an additional thunderstorm.
Temperatures Monday remain cool, generally in the 60s for lower
elevation locations, then slightly warmer into the lower 70s for
Tuesday. Upper ridge builds back into the region for most of the
week, allowing temperatures to climb back above normal by mid to
late week. Model means flatten the ridge ahead of a system cutting
into the Great Basin from the California coast late in the week, but
there is still a lot of model spread regarding how fast the ridge
breaks down.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Keyes
LONG TERM...Keyes
AVIATION...13
FIRE WEATHER...DMH

NWS PIH Office Area Forecast Discussion