766
FXUS65 KPIH 110837
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
237 AM MDT Tue Jun 11 2024

.SHORT TERM...Today through Wednesday night.
Expect clear skies through Wednesday with minimal weather impacts
in the short term period. Will get a bit breezy on Wednesday as
strong zonal flow aloft sets up and expect some 15 to 25 mph
sustained winds in the Snake River Plain with gusts up to 30 mph.
Mountain high temperatures will be in the 70s today with low
elevations in the mid to upper 80s. Lows tonight will be in the
40s to 50s and highs Wednesday again 70s to lower 80s mountains
and mid to upper 80s in valleys.
GK


.LONG TERM...Thu through Mon night. Upper level high pressure
remain in control through at least Fri, then a low begins the
breakdown of the ridge, possibly as early as Sat afternoon. The
breakdown on Sat has 30 to 35 percent chance of occurring, so it is
more likely that Sat will be dry in eastern Idaho, slightly higher
for central Idaho. The low is expected to cross through Idaho on Sun
and Mon, with only a 10 to 15 percent chance of staying farther
north and keeping things dry. 500mb heights are falling by Sat
afternoon, and thus a cool-down should start by then. Guidance is
indicating an 8 to 11 degree cool-down to the high, which will bring
afternoon highs to around seasonal normals. By Sun, temperatures
could be below normal, or at least bottom out. Then warm-up returns
Monday.

The Sat-Sun front looks like it packs considerable wind with limited
precipitation. Best thunderstorm days appear to be the Fri
afternoon/evening prior to passage and then Sat afternoon/evening.
Positive tilt trough would tend to favor non-severe level convection.
Messick

&&

.AVIATION...High pressure will dominate, and the only clouds
expected are with a shortwave embedded in the moderate to strong
westerly flow that slides through during the late night hours
Tuesday night. And even with that, no CIG is expected, anywhere. No
precipitation or TSRA with the very dry air and only weak
instability in the WY-ID border region. With the upper level
support, expect gusty afternoon and evening wind for the valley
airports. Messick

&&

.FIRE WEATHER...Warm up and drying out continues through Thu
afternoon. Lower elevation humidity in the central Idaho mountains
and eastern Magic Valley should drop below 15 percent on at least
two of the three days. Expect afternoon/evening gusty wind each day,
with an increase in the wind on Fri.

Humidity will start to rise with the approach of a front on Fri,
then what looks like a fairly dry cold front will push through on
Sat, amping up the wind and producing dry thunderstorms. 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 and is
expected to remain at that level through this afternoon, aided by
additional snowmelt from the Tetons and Big Holes. With the
latest NWRFC forecast showing this gage dropping below minor stage
on Tuesday, have gone ahead and added an expiration time for the
warning to be 3 PM this afternoon. This may need to be adjusted
dependent on future flows and trends going forward, with warmer
temperatures certainly still leading to additional snowmelt. This
additional snowmelt is expected to keep the river in action stage
through much of this upcoming week. Further downstream along the
Teton River near St. Anthony, that gage remains at action stage
and is only a couple inches away from minor flood stage. That gage
is expected to crest today and come down below action stage by
Wednesday.

Several other rivers across the CNTRL Mountains are also seeing
diurnal increases with the Big Lost River at Howell Ranch
currently hovering around action stage. Along the Snake River,
increased flows out of Palisades Reservoir have also led to the
Snake River near Heise gage climbing up to action stage and it is
expected to stay there until further notice. MacKay

&&

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

$$