515
FXUS65 KPIH 041944
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
144 PM MDT Thu Jul 4 2024

.SHORT TERM...Today and Friday.
Our area is currently under high pressure with weak northwest
flow aloft as the high pressure ridge axis is just off the Pacific
coast. High pressure will strengthen slightly through the period
bringing continued dry conditions, overall clear skies, and
gradual warming. Winds will be slightly breezy in the afternoon,
gusts of around 15 to 25 mph, especially on Friday afternoon as a
weak trough passes over western Montana. Temperatures will be a
few degrees below normal today and rise to around normal on
Friday.
Wyatt

.LONG TERM...Saturday through next Thursday.
Under the increasing influence of a broad H5 ridge of high pressure
through the weekend into early next week, temperatures will see a
warming trend as conditions remain very dry with near record to
record warmth possible by the middle of next week. With the H5 ridge
axis situated along the Pacific Coast for Saturday, this axis will
shift east heading into next week which will lead to increasingly
warm temperatures. Slightly breezy winds are also expected Saturday
as a passing H5 trough works through Montana which will lead to
gusts around 20-40 mph with a 10% chance of isolated showers and
thunderstorms up around Island Park. Highs midweek next week will
peak in the 90s to low 100s which is about 10-15 degrees above
normal for this time of year. Given near record to record warmth is
expected, HEAT ADVISORIES and or EXCESSIVE HEAT WARNINGS will likely
be needed around this timeframe, preceded by an EXCESSIVE HEAT WATCH
for either product. In the meantime, enjoy the seasonable
temperatures through the weekend before next weeks warming trend.
MacKay

&&

.AVIATION...Expect VFR conditions from high pressure bringing
overall light winds, dry conditions, and mostly clear skies.
Wyatt

&&

.FIRE WEATHER...
Under the increasing influence of high pressure through the weekend
into early next week, temperatures will continue to see a warming
trend with highs peaking midweek next week in the 90s to low 100s
across our lower elevations. Given this warm and very dry air mass
in place, RHs will reach the single digits and teens most afternoons
in the lower elevations with winds both Friday and Saturday
approaching and or reaching that 30 mph gust threshold around FWZ
425/427 given a series of passing H5 shortwave troughs along the
Continental Divide.

As a result, near critical fire weather conditions will be possible
in FWZ 425/427 from 1500 to 2100 Friday due a to a combination of
wind gusts to around 25-30 mph and RH around 10-15%. In addition, a
FIRE WEATHER WATCH is now in effect from 1200-2100 Saturday for a
combination of wind gusts to around 30-40 mph and RH around 8-12%.
In addition to an increase in wind, there will be around a 10%
chance of isolated showers and thunderstorms around Island Park
Saturday afternoon. Outside of those two breezy days on Friday and
Saturday, winds will remain sub-critical as very dry conditions
continue through all of next week as a H5 ridge axis shifts directly
overhead.
MacKay

&&

.PIH WATCHES/WARNINGS/ADVISORIES...

Fire Weather Watch from Saturday afternoon through Saturday
evening for IDZ 425 and 427.

&&

$$