Ammon, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

487
FXUS65 KPIH 141729
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
1129 AM MDT Mon Apr 14 2025

.KEY MESSAGES...

- High pressure will produce warm, dry weather into midweek.

- Increasing confidence in next storm system for mid to late
  week with return to cool unsettled conditions.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 140 AM MDT Mon Apr 14 2025

Upper ridge will begin to build into the area today. We should see
above normal temps today as highs in the Snake Plain and Magic
Valley in the 60s today and even warmer on Tuesday with highs in the
70s. The NAM is trying to develop thunderstorms from some mid level
moisture to our south late Tuesday afternoon, pushing the remnants
into southern Idaho Tuesday night. The GFS/European aren`t as
aggressive with the convection, but this is something to potentially
watch.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 140 AM MDT Mon Apr 14 2025

Wednesday is shaping up to be a transition day between above
normal temperatures and dry conditions to start the week to a
return to precipitation chances and cooler temperatures starting
Thursday as a split 500 mb trough builds east from the Pacific.
Conditions will stay dry to start the day Wednesday ahead of
isolated showers moving in for the afternoon and evening hours.
Winds will also increase during that timeframe as 20-35 kt 700
mb winds aloft support winds peaking around 10-25 mph with gusts
to 25-40 mph. Highs on Wednesday in the 60s/70s will drop about
15-20 degrees for Thursday with highs returning to the 40s/50s
associated with our next system moving in.

As this split trough continues its progression east on Thursday, two
well defined areas of low pressure are expected to develop with one
dropping south through the northern Rockies and another working east
through the southwest CONUS. The northerly of these two lows will be
the driver of isolated to scattered precipitation chances throughout
the day Thursday with widespread cloud cover and gusty winds
allowing for much cooler, below normal temperatures as this low
tracks south through the PacNW and northern Rockies. Snow levels
initially starting up in the mountains will progressively fall to
valley floors throughout the day Thursday into Thursday night,
supporting a mix of rain and snow showers regionwide. 48-hour
rainfall/SWE totals from late Wednesday through early Friday have
remained consistent with previous forecasts, showing a T-0.25" in
the valleys and 0.25-0.75" in the mountains. Snowfall amounts during
this timeframe will remain light with a T-1" possible in the valleys
and 1-4" in the mountains, locally higher in that 4-6" range.

Winds on Thursday will also remain elevated courtesy of a backdoor
cold front dropping northeast to southwest with breezy northerly
winds expected in the Central Mountains, Upper Snake River Plain,
and Eastern Highlands while winds remain out of the west or
northwest for locations further south. Winds will peak Thursday
afternoon/evening and will remain elevated into Friday morning.
Winds during this timeframe look to peak around 15-35 mph with gusts
to 30-50 mph, strongest across the Upper Snake River Plain and
eastern Central Mountains. Given our typical W/SW wind events and
more atypical stronger N/NE winds, these winds will be something to
watch for a potential Wind Advisory issuance. For those areas
starting off with W/NW winds, we will see a transition over
regionwide to N/NE winds Thursday night into Friday morning.

With this 500 mb low dropping south through the Great Basin for
Friday, a ridge of high pressure is expected to begin building into
the northern Rockies with drier conditions back for Friday building
in northwest to southeast as isolated to scattered showers persist.
Temperatures will see a warming trend heading into the weekend as
the ridge axis shifts overhead with highs back in the 50s/60s. With
this ridge feature weakening and shifting east for Sunday, this will
set the stage for several waves of moisture to build in out of the
northeast Pacific and western Canada, supporting daily precipitation
chances back in the forecast starting Sunday into early next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1128 AM MDT Mon Apr 14 2025

VFR conditions will continue through Tuesday. Winds remain light
under the influence of high pressure.

&&

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

&&

$$

SHORT TERM...13
LONG TERM...MacKay
AVIATION...DMH