FXUS65 KBOI 190557

AFDBOI



Area Forecast Discussion

National Weather Service Boise ID

1157 PM MDT Wed Mar 18 2026



.UPDATE...Updated aviation discussion.



&&



.KEY MESSAGES...

- Record high temperatures through Friday with dry conditions.



- Breezy conditions and low relative humidity will create fire

  danger concerns for central Oregon Thursday and Friday 

  afternoons.



- A pattern shift with a cold front on Saturday will bring

  cooler temperatures, mountain precipitation, and breezy

  westerly winds.



&&



.SHORT TERM /Through Friday Night/...

Issued 205 PM MDT WED MAR 18 2026

An unseasonably strong upper level ridge will continue to 

strengthen over the southwest United States over the next day. 

While the most extreme heat will remain over the southwest US, 

this will bring several days of record high temperatures to 

southeast OR and southwest ID. Temperatures will be 20-25 

degrees above normal, with the lowest valleys seeing low to mid 

80s and the mountains reaching the 60s through Friday. Breezy

conditions and low relative humidities will be of concern in

Harney County for fire danger on Thursday and Friday afternoons.



&&



.LONG TERM /Saturday through Wednesday/...

Issued 205 PM MDT WED MAR 18 2026

A cold front come Saturday will mark the start of a pattern 

shift for the area. While most of the area will remain dry, this

cold front will allow for a 30-65% chance of precipitation 

across the higher terrain of our northern zones. Elsewhere, 

increased cloud cover and breezy conditions can be expected. 

Saturday afternoon, areas east of Boise in the Snake Basin have 

a 50-85% chance of seeing wind gusts of at least 25 mph. 

Temperatures will drop by 10-15 degrees Saturday following the 

frontal passage. 



With the cold front switching us into zonal flow aloft,

conditions will remain cooler (although still leaning above 

normal) and breezy throughout much of the long-term period. 

Embedded shortwaves will allow for periods of showers across 

higher terrain and clouds area- wide. Come Tuesday/Wednesday, 

there is considerable uncertainty regarding a Gulf of Alaska Low

and its subsequent evolution. This, in turn, is lowering 

confidence in temperatures and precipitation timing. For now, am

maintaining temperatures near the NBM mean, with precipitation 

chances increasing through Tuesday afternoon into Wednesday. 

Both of these factors depends on the speed of the system and our

residence time within the warm sector, which will become better

refined in the days to come.



&&



.AVIATION /06Z Thursday through Friday/...

Issued 1156 PM MDT WED MAR 18 2026



VFR with high clouds. Surface winds: variable up to 10 kt. Then, SW-

NW 5-15 kt by Thu/18Z. Afternoon gusts to 20-30 kt for E Oregon and 

near NV-ID border. Winds aloft at 10kft MSL: W-SW 15-30 kt. 



KBOI...VFR and mostly clear. Surface winds: SE 5-10 kt, then NW-N 

around 5 kt in the afternoon.



&&



.BOI WATCHES/WARNINGS/ADVISORIES...

ID...None.



OR...None.



&&



$$



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AVIATION.....SH

SHORT TERM...KA

LONG TERM....NF