687
FXUS65 KBOI 121515
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
915 AM MDT Sun Oct 12 2025

.DISCUSSION...Upper trough continues to bring light rain and
snow showers to Idaho north of the Snake Basin this morning.
The trough is weakening and moving east. Another upper trough
is deepening and moving southward along the NW coast and will
bring more rain to eastern Oregon and the west central Idaho
mountains tonight through Monday morning. The trough will
become an upper low off WA this evening and will be just off
the OR coast Monday. The low will turn inland across northern
California Tuesday, northern Nevada Tuesday night, and into
southeast Idaho Wednesday, with widespread rain and high-
mountain snow for southern and eastern parts of our CWA.
Today`s models look wetter on this system than they did
yesterday. Continued cool today, several degrees warmer
Monday and Tuesday, then cooler again Wednesday. Current
forecast covers things well. No updates.

&&

.AVIATION...Mainly VFR, except MVFR/IFR in scattered to numerous
rain and snow showers north of the Treasure Valley, near KBKE-KMYL.
Mountains obscured in precipitation. Snow level 5000 to 6000 feet
MSL. Surface winds: SW-NW 5-15 kt with gusts up to 25 kt. Winds
aloft at 10kft MSL: W-NW 20-30 kt.

KBOI...VFR. Surface winds: SW-W 10 kt or less.

&&

.PREV DISCUSSION...
SHORT TERM...Today through Tuesday night...Showers continue
over the mountains this morning before tapering off by sunrise.
An upper level low near Vancouver Island will move south along
the coast in the short term toward northern CA on Monday and
southern CA on Tuesday. As the trough moves south along the
coast, precipitation redevelops over Baker County and the west
central ID mountains this afternoon and becomes widespread over
eastern OR late tonight into Monday morning, generally staying
north and west of a line from Rome OR to Boise ID. By Monday,
precipitation lingers over central OR, with breezy east-
southeast winds as the trough continues to move south. Strong
southerly flow will advect subtropical moisture into the area on
Tuesday with showers likely over much of the area.

LONG TERM...Wednesday through Sunday...On Wednesday, the trough
over CA moves northeast over the Great Basin and southern ID
with widespread precipitation on Wednesday. Wrap around moisture
continues on Thursday with showers likely over the Idaho zones,
with dry northerly flow in eastern OR. Dry conditions on
Thursday through Sunday with northwest flow aloft. While both
the deterministic and ensemble guidance show good agreement on
the overall pattern, forecast confidence in the long term
remains low due to the extreme amount of energy coming out of
the western Pacific from typhoons moving into the jet stream
upstream of us.

&&

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

&&

$$

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