755
FXUS65 KBOI 301511
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
911 AM MDT Thu May 30 2024

.DISCUSSION...Current forecast is on track with sunny, cool weather
with lighter winds today, then sunny again and 8-10 degrees warmer
Friday as a Pacific upper ridge approaches. Increasing clouds and
another 5 degrees warmer Saturday under southwesterly flow aloft
ahead of the next approaching Pacific trough. A weak surface cold
front will pass through our CWA Saturday night. Valley County/ID
will have a 15-25% chance of showers and thunderstorms late
Saturday and Saturday evening but the rest of our CWA will stay
dry. Clearing Sunday with little if any cooling behind the weak
cold front. The next Pacific trough will bring a stronger cold
front Monday, with showers and thunderstorms, gusty winds, and
cooler temps. Models are in good agreement through Monday but
diverge beginning Tuesday. Even so, the latter half of next week
looks hot and dry. No updates.

&&

.AVIATION...VFR. Scattered cumulus over the w-central Idaho mtns,
otherwise clear. Surface winds: W-NW 5-15 kt with gusts 20-30 kt
through 03Z this evening east of KBOI. Winds aloft at 10k ft MSL:
W-NW 15-25 kt.

KBOI...VFR. Northwest winds through sunset, then light and
variable.

Weekend Outlook...VFR through Sunday. Increased clouds and a slight
chance of showers and thunderstorms in the w-central Idaho mtns,
north and east of KMYL on Saturday. Clouds increase late Sunday with
chance of showers across e-central Oregon in the evening. Winds less
than 10 kt on Friday, becoming W-NW 5-15 kt with local gusts to 25
kt Saturday and Sunday.

&&

.PREV DISCUSSION...
SHORT TERM...Today through Saturday night...Northwest flow aloft
today transitions to a weak upper ridge on Friday, resulting in
dry conditions with mostly clear skies. Temperatures trend warmer,
from below normal today to near normal on Friday. Breezy west-
northwest winds develop on the Snake Plain (east of Boise) by
late morning that will continue through early this evening.
Otherwise winds will be light through Friday. The warming trend
continues on Saturday with highs 5 to 10 degrees above normal.
A weak upper trough approaches from the west on Saturday and
moves through Saturday night. Moisture will be limited and
confined to the far north for a slight chance (less than 25
percent) of afternoon and evening showers and thunderstorms in
northern Valley County. Breezy west-northwest winds develop late
in the afternoon and continue overnight as a weak cold front
moves through the region.

LONG TERM...Sunday through Thursday...Models remain in good
agreement about the overall pattern though the extended. A weak
upper level ridge will move overhead on Sunday, bringing dry
conditions with temperatures a few degrees above normal. An
upper level trough and surface cold front will move across the
Pacific Northwest on Monday. This system will have a good
moisture tap and will bring a chance of showers to the area.
The highest chance (50-80%) will be across Baker County and the
west-central Idaho mountains with a 10-50% chance elsewhere,
lowest in the Magic Valley. The cold front is expected to arrive
early in the day, limiting potential for thunderstorms, but a
slight chance of thunderstorms will develop later in the day as
the trough moves overhead. The trough should bring slightly
cooler temperatures Monday and Tuesday along with breezy winds.
On Wednesday and Thursday, ensembles are in good agreement about
an upper level ridge building across the West. This will allow
temperatures to climb to well above normal, with lower valley
highs in the 90s likely (60-70% chance) by Thursday, and even a
10% chance of highs hitting 100 degrees.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.
OR...None.

&&

$$

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DISCUSSION...LC
AVIATION.....DG
SHORT TERM...BW
LONG TERM....ST