316
FXUS65 KPIH 120749
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
149 AM MDT Wed Jun 12 2024

.SHORT TERM...Today through Thursday night.
Main impact today will be breezy to windy conditions in the Snake
River Plain. Strongest winds will be in the northern parts mainly
across the Arco/Mud Lake Desert region. Some sustained winds of 20
to 30 mph with gusts over 40 mph are likely. Generally 10 to 20
mph sustained winds with gusts up to 30 mph are likely in the
Eastern Magic Valley and Snake River Plain regions from American
Falls to Pocatello to Idaho Falls over the interstate region.
Think will stay mainly below advisory and lake wind advisory
criteria. Will see strongest over INL sites. Will remain dry with
highs in the 70s mountains to mid to upper 80s in lower
elevations. Lows tonight will be in the 40s and 50s and it will be
hot on Thursday with highs in the 80s mountains and lower 90s in
much of the Eastern Magic Valley and Snake River Plain. A weak
wave may bring some isolated showers or thunderstorms late in the
day Thursday and Thursday evening in the southern hills, magic
valley and Upper Snake Highlands. Winds will be lighter Thursday
with the strongest in the Arco and Mud Lake region and Lost River
Range in the 10 to 20 mph range.
GK

.LONG TERM...Fri through Tue night. The expected weekend trough has
been slowed a little from yesterday`s thinking. Fri still appears
mostly dry except for a slight chance in the northeast corner in and
around the Island Park area during the day Fri. The cloud cover will
mean cooler temperatures compared to Thu, with temperatures down 5
to 10 deg F in the western zones, slightly down in the eastern half.
Sat now looks like the trough may arrive during the overnight,
although only 53 percent of the cluster solutions has the upper
level trough deep enough to generate showers and thunderstorms in
the forecast area. Sun through Tue night has the upper level trough
sitting right overhead for the entire period. Expect cooler and
unsettled weather during this period.

Wind appears moderate to strong Fri through Sun and may not be
limited to afternoons. Afternoon temperatures will stay below
climatic normals starting Sat. And there is a gradual cooling trend
over the Sat-Tue period with widespread temperatures staying below
70 deg F apparently by Mon, even in the Snake River plain. Messick

&&

.AVIATION...Strong wind aloft will mix down in the SKC-SCT skies and
produce gusty afternoon and evening wind. The upper level ridge
should remain in place, with wind gradually getting stronger into
the weekend when a trough gets close enough. It appears as though
the southern airdromes will have the most cloudiness tonight, but
still in the FEW-SCT category, and at mid-levels, so not expecting
any SHRA/TSRA risk. Messick

&&

.FIRE WEATHER...Temperatures are still on a warming trend, but a
trough passing well to the north in Canada will bring an increase in
humidity from today to Thu. Strong westerly to southwesterly flow
will continue, peaking in the afternoon and evening at the surface.
Inversions will still develop and there should be some relief from
the wind until the inversion breaks mid-day. Low elevations in the
Salmon Challis NF region and over the Arco Desert and Lava Beds
should see humidity drop below 15 percent today, not quite as much
on Thu, even though temperatures reach their hottest on Thu
afternoon.  Messick

&&

.HYDROLOGY...
A FLOOD WARNING remains in effect for the Teton River near Driggs
as small streams/creeks and the main stem river continue to run
high. Minor flooding is being observed on the Teton River near
Driggs and is expected to remain at that level through Saturday,
aided by additional snowmelt from the Tetons and Big Holes. The
latest NWRFC forecast shows this gage peaking Wednesday and
dropping below minor stage on Saturday. The warmest temperatures
this week are expected this Thursday, which will keep flows going
through early Saturday. However, below normal temperatures this
weekend, along with a diminishing snowpack, will cause flows to
drop off fairly quickly this weekend into early next week. Further
downstream along the Teton River near St. Anthony. This gage
remains at action stage and crested yesterday and is forecasted to
come down below action stage by Friday.

Several other rivers across Southeast Idaho are also seeing
diurnal increases. The Big Lost River at Howell Ranch is still
currently hovering just below action stage. The Mackay Reservoir
will fill in the next day or two, which will cause increased flows
below the Mackay Reservoir on the Big Lost River. Along the Snake
River, increased flows out of Palisades Reservoir have led to the
Snake River near Heise to climb up to action stage and it is
expected to stay there until further notice.
MacKay/Wyatt

&&

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

$$