343
FXUS65 KBOI 240337
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
937 PM MDT Thu May 23 2024

.DISCUSSION...A weak ridge will transition over the area tonight
bringing mostly clear skies and cool temperatures. The next
frontal system will arrive from the northwest on Friday
afternoon, with showers and thunderstorms (20-40 percent chance)
developing along the front. Baker County will see higher chances
of precipitation (60-90 percent chance) as the center of the
shortwave moves over that area. The front will bring breezy
west-northwest winds as it moves through. No updates.

&&

.AVIATION...VFR. Patchy fog and mountain obscuration overnight.
Showers and thunderstorms developing in eastern OR Fri afternoon
moving across SW Idaho in the evening. Surface winds: E-SE
5-10kt, becoming NW 10-20kt behind the front on Friday
afternoon. Winds aloft at 10k ft MSL: variable 10 kt or less,
becoming W 10-20 kt by 24/12Z.

KBOI...VFR. SE 5-10 kt, shifting to NW 10-20 around 3-6z/Sat
with rain showers.

Weekend Outlook...VFR. Lingering showers on Saturday morning.
MVFR/IFR possible in precip, along with mountain obscuration.
VFR and dry Sunday. Snow levels generally 6500-7500 ft MSL.
Surface winds W-NW 10-20 kt with gusts to 25-30 kt Saturday.
Sunday winds W-NW 5-15 kt.

&&

.PREV DISCUSSION...
SHORT TERM...Tonight through Saturday night...Mostly cloudy,
breezy, and cool weather today behind yesterday`s departed
trough will become mostly clear and cold tonight with light
winds. Weak upper ridge will pass through Friday with max temps
6-10 degrees higher than today. Clouds will increase in Baker
County and northern Harney County as the next upper trough
approaches from the BC coast. The trough will bring a 60-90%
chance of showers to our northern CWA mountains Friday night and
Saturday morning, 30-60% chance to eastern Oregon and southwest
Idaho mountains, and 20-40 percent chance to the Snake Basin
and southern Idaho valleys. Rain amounts will be generally less
than .10 inch, except up to .25 inch in northern mountains. Snow
level will lower to 5500-6000 feet but snowfall will be
minimal, generally less than one inch. Saturday will be breezy
and cooler again as the upper trough shifts east. Saturday night
should be clearing and cool with decreasing west winds.

LONG TERM...Sunday through Thursday...The departing trough will
leave us with weak ridging Sunday, and then SW flow aloft will
move in Monday. This SW flow is ahead of a deep and strong
trough off the coast, and will lead to rapidly warming
temperatures and dry conditions. Temps will warm up to a few
degrees below normal Sunday, then 5-10 degrees above normal
Monday, and around 20 degrees above normal Tuesday. The
aforementioned trough off the coast will move inland by
Wednesday, lowering heights and therefore cooling things down a
bit for Wed and Thu. The trough will also produce a chance
(10-30%) of showers across the north Tue night through Thursday.
Only light precipitation amounts are forecast at this time.

&&

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

&&

$$

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DISCUSSION...KA
AVIATION.....KA
SHORT TERM...LC
LONG TERM....SP