Fire Weather Watch 6, NWS Pocatello, ID

Area Forecast Discussion
National Weather Service Pocatello ID
131 PM MDT Mon Jul 12 2021

.SHORT TERM...Tonight through Wednesday night. Strong high pressure
prevails over CA/NV with moisture staying to the south. Smoke
appears a little less dense over southeast Idaho, but still noted on
satellite imagery. An upper trough will work its way into central
Idaho by tomorrow morning, and we should see winds increase across
the Snake Plain by noon. Later tomorrow afternoon, models are
supporting convection mainly east of Interstate 15. Storms that do
form around the Island Park to Driggs areas will have potential to
approach severe with 40 to 45 kts of 0-6km shear and 400-600 J/Kg
MUCAPE. Forecast soundings show PW around 0.7 to 0.8 inches in the
Island Park area tomorrow, which may support some moderate showers.
We'll see a rather weak ridge build into the area on Wednesday as we
return to a hot and dry pattern. Hinsberger

.LONG TERM...Thursday through next Monday. A low pressure center is
expected to gradually move toward the NW coastal waters as the ridge
that has been over the Great Basin shifts east into the Rockies and
WRN Wyoming leaving SE Idaho under a modest Sw flow aloft. Ill timed
ejecting short-wave disturbances and shallow intrusions of moisture
from the south may provide an opportunity for periods of enhanced
winds and isolated thunderstorm activity from time to time. At this
time, the best chance for those days appears to be Thursday
afternoon, Saturday afternoon, and Sunday afternoon. Again,
confidence is low on the timing aspects but the pattern is
supportive of events. Temperatures are expected to moderate ever so
slightly during the period. Huston
&&

.AVIATION...A weak upper trough will swing through central Idaho
early tomorrow morning, so we may see winds pick up towards the end
of the TAF period. Satellite imagery shows widespread smoke covering
much of southeast Idaho, but some relative clearing may work its way
in from the southwest. Visibility should predominantly stay VFR,
though we can't rule out brief MVFR conditions today. With the
approach of the upper trough tomorrow, we could see winds increase
around mid-morning. Precipitation should hold off until tomorrow
afternoon. Hinsberger
&&

.FIRE WEATHER...A dry upper trough will work its way into central
Idaho tomorrow morning, and we should see winds begin to pick up mid
to late morning. By tomorrow afternoon, the combination of winds and
RH will lead us in critical fire conditions focused around fire
zones 410,413, 425, and 427. Isolated dry thunderstorms may develop
east of Interstate 15 later tomorrow afternoon ahead of the trough
axis. For the rest of the week, we'll see a broad westerly flow over
the region. On Thursday, an upper disturbance will push into
southeast Idaho helping to trigger some isolated thunderstorms.
Beyond that, we'll see ridging amplify over the Rocky Mountains
while a deep trough develops in the East Pacific. Widespread Haines
index of 6 will be in place over southeast Idaho over the next few
days. Models keep us hot and dry for the most part, but we'll have
to keep our eye on any shortwave that lifts from the Pacific trough,
as it may become the focus of thunderstorms or even a bump in the
windspeeds that may nudge us into critical fire weather conditions.
Hinsberger
&&

.AIR STAGNATION...
The accumulation of smoke from distant fires in NE California, SRN
Oregon, and SE Washington as well as fires in the CNTRL Idaho
mountains may produce moderate to unhealthy air quality conditions
across SE Idaho as the flow aloft advects much of the smoke east
into our area over the next several days. Huston
&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory continues until 9 PM MDT this evening for IDZ051-
055>057.

Fire Weather Watch from Tuesday afternoon through Tuesday evening
for IDZ410-413-425-427.
&&