textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- Turning hotter Sunday with lower elevations hitting 90 for the first time this year.

- Record highs possible on Tuesday with temperatures in the mid to upper 90s in the lower valleys.

- Not as hot with a slight chance of precipitation in the mountains starting Wednesday.

SHORT TERM /Through Monday Night/

Issued 400 AM MDT SAT MAY 9 2026 A weak cold front has moved through the area this morning with breezy west to northwest winds overnight. Temperatures will be similar to yesterday, with highs around 5-10 degrees above normal. The warm air mass under the building ridge will shift into our region on Sunday, bringing an abrupt warmup. As winds become easterly, high temperatures on Sunday will push to 15-20 degrees above normal. This will put lower elevation sites near 90 and mountain valleys into the upper 70s. Temperatures will be within 5 degrees of records at many locations Sunday. A weak shortwave will bring increased clouds on Sunday evening into Monday morning with slightly cooler temperatures on Monday.

LONG TERM /Tuesday through Saturday/

Issued 400 AM MDT SAT MAY 9 2026 Strong ridging will continue to extend over the region on Tuesday. Tuesday will see temperatures up to 25 degrees above normal, with valley areas potentially reaching the mid to upper 90s. A very weak cooldown is expected Wednesday, as temperatures are still projected to be 10 to 20 degrees above normal. Considerable guidance uncertainty remains over the incoming Pacific pattern midweek through the end of the week. For now, Wednesday will see a 20 to 30 percent chance of precipitation mainly over mountain areas. Depending on the timing and pattern of the incoming Pacific low, Thursday may see area-wide precipitation and convective chances. The unsettled pattern towards the end of the week will likely bring a cooldown Friday through Saturday, with temperatures potentially returning to near-seasonal normals. Long-range guidance also hints at a more northerly trough potentially digging across the region on Saturday.

AVIATION /12Z Saturday through Sunday/

Issued 559 AM MDT SAT MAY 9 2026 VFR with few high clouds to the south near NV border. Surface winds: W-NW 5-10 kt, except SW-NW 10-15 kt with gusts 20-25 kt near KTWF/KJER this morning through afternoon. Gusts 20-30 kt expected east of KBOI in the afternoon. Winds aloft at 10kft MSL: NW 20-30 kt.

KBOI...VFR. Surface winds: NW 6-12 kt throughout morning, with gusts 16-20 kt in the afternoon.

Sunday Outlook...VFR. Surface winds SW-SE 10-20 kt. A cold front Sunday night will return NW gusts of 15-30 kt. Strongest late evening gusts expected over KBKE and KONO.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.