Red Flag Warning 5, NWS Pocatello, ID

Area Forecast Discussion
National Weather Service Pocatello ID
316 PM MDT Wed Jul 13 2022

.SHORT TERM...Today and Thursday.
High pressure ridge located over the four corners region will
continue to shift eastward while monsoonal moisture works
northeastward across the region throughout the afternoon. With
daytime heating and decreasing stability, convection will continue
to increase throughout the afternoon. The Storm Prediction Center
has the entire region in at least a general thunder risk, with
the very northern portion of the eastern highlands in a marginal
risk. Outside of convection, today will be breezy, with 20-30 mph
gusts likely this afternoon across the region. Of greater impact
though will be gusty outflow winds associated with isolated to
scattered convection across the CWA today and tonight, with DCAPE
values of 1,500 J/Kg, give or take. While gusts up to 50 mph will
be the main concern, small hail can't be ruled out. The
environment in the general area of the marginal risk will be a bit
more favorable for supporting slightly larger hail and stronger
winds due to increased shear and greater instability. High
temperatures today and tomorrow will be similar to yesterday, with
low elevations reaching the mid to upper 90s and some areas
potentially breaking 100 degrees. The current Heat Advisory will
continue through 9 PM tonight for portions of the eastern Magic
Valley, Arco Desert, Snake Plain, and southern highlands.
Thunderstorm potential continues tomorrow, confined mostly to the
eastern highlands and Central Mountains. Cropp

.LONG TERM...Friday through Wednesday.
The broad synoptic pattern remains a record on repeat with high
pressure to our south and low pressure to our northwest. This will
keep our area mostly tapped into the monsoonal moisture feed
especially as the upper high stays east of the four corners region.
This weekend ensemble guidance showing this high pulling back to the
west after a weak disturbance rides up and over Friday afternoon.
This will temporarily disrupt the moisture feed Saturday, but it
should be re-established heading into next week. A disturbance will
move into the Pac NW early next week, but the well established high
pressure will deflect most of the energy to our north. The result
will be continued unseasonable warmth through the middle of next
week. TAX

&&

.AVIATION...Convection has initiated across the SW portion of our
CWA and will continue to expand northeastward throughout the
afternoon and evening. Have included VCTS at all sites,
transitioning to VCSH late tonight, with clouds scattering
overnight and through the morning. Winds will be breezy region-
wide outside of convection, so have forecast gusts over 20 kts
until after sunset. Degraded conditions and strong wind gusts
associated with convection will be possible through tonight. Cropp

&&

.FIRE WEATHER...Beginning to see shower and thunderstorm activity
blossom over zone 427 as of 2pm. We're expecting this coverage to
expand further, stretching to the north and east. This activity will
likely creep into 413 and 410 by the end of the evening, but
coverage in these zones should be less. Red Flag Warning continues
for 427 through this evening.

Looking forward to tomorrow, overall support for convective
development is lower than Wednesday, but enough residual moisture
will linger into Thursday afternoon/evening. This should allow
additional isolated to scattered thunderstorm development,
particularly over zone 413. Overall confidence in coverage is low to
moderate, so have decided to hold off on a new Red Flag Warning for
413. Another round of convection is then expected Friday, as another
wave passes along the north side of the ridge. Additional support
from this passing disturbance will likely boost storm coverage and
intensity.

Surface winds will top out just below critical thresholds each
afternoon, especially across the Snake Plain zone 410, but
minimum RH values hover near or just above 15 percent until
Saturday when a little drier air gets into the mix. TAX

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 9 PM MDT this evening for IDZ051>059.

Red Flag Warning until 10 PM MDT this evening for IDZ427.

&&