Damaging Winds in Idaho, May 10, 2025

Area Forecast Discussion
National Weather Service Pocatello ID
230 PM MDT Sat May 10 2025

.KEY MESSAGES...

- Marginal Risk for severe convection today and Sunday. Main threat
will be strong wind gusts.

- Lake Wind Advisory for American Falls Reservoir today, and
possibly Sunday.

- Unsettled and breezy throughout the week with much cooler
  temperatures on tap.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 230 PM MDT Sat May 10 2025

Very warm temperatures remain on tap for today, with record or near
record highs at several locations. Gusty winds continue to support a
marginal Lake Wind Advisory for American Falls Reservoir into early
evening. The very warm temperatures will be enough to help spur the
development of thunderstorms this afternoon and evening. Model
soundings support potential for strong outflow winds in excessive of
40 mph especially in light of very dry surface dewpoints and steep
lapse rates. A few gusts could exceed severe thresholds, and
portions of the region remain under a Marginal Risk for severe
weather. The strongest convection is expected to diminish around
sunset, but showers will continue overnight. Stronger convection
redevelops during the day Sunday, and instability remains strong
enough to support another Marginal Risk for severe weather. Once
again, strong outflow winds remain the main concern. Another round
of gusty winds will be of concern, and another Lake Wind Advisory
will likely be needed.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 230 PM MDT Sat May 10 2025

Active pattern continues with upper trough moving across the state
through Wednesday. Models remain in good agreement with progression
of the low early in the week, but begin to diverge by Wednesday with
placement of the closed center and depth of the trough as it shifts
east. Monday and Tuesday remain deeply unsettled and breezy with a
drastic cooling trend, especially compared to this weekend's high
temps. There are still close to 20% of the cluster members holding
on to a deeper trough with axis anchored over the Great Basin by
Wednesday, though the rest of the clusters support the means by
moving a closed or partially closed low across Yellowstone by
then. The means solution would support a trend toward a decrease
in precipitation late Wednesday. Wednesday does look to the be
the coldest day of the week, with lower elevation highs
generally in the 50s for most locations. Snow levels do lower
Tuesday into Wednesday at the coolest, but bottom out at
roughly 6000-6500 ft. It's still early to try to pin down
accumulations, but in generally 2-8" of snow above 6000 ft is a
good starting estimate, with peaks above 8500 ft seeing
potential for more. Temperatures begin to bounce back up
Thursday/Friday under the influence of transitory high pressure
but still unsettled for mainly afternoon/evening
showers/thunderstorms.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1118 AM MDT Sat May 10 2025

Breezy southwest winds will develop this afternoon as strong
daytime heating mixes stronger winds aloft to the surface.
KPIH, KIDA, and KBYI will see the strongest winds, with gusts to
around 25 kts. Scattered showers and thunderstorms will develop
this afternoon and linger into the evening hours. The most
favorable window for thunderstorms will be 21-02Z. The main
threat from these high-based storms will be strong wind gusts
around 35 kts or higher. Could also see some brief MVFR
conditions with the strongest storms, but otherwise anticipating
VFR conditions to persist. Look for light rain showers to
linger overnight, but VFR conditions are still likely with
these.

&&

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

&&

SHORT TERM...DMH
LONG TERM...DMH
AVIATION...Keyes