textproduct: Boise

UPDATE

Updated aviation discussion.

KEY MESSAGES

- A cold front arrives this evening with widespread showers through Tuesday morning. - Seasonably cool on Tuesday with a slight chance of thunderstorms in the central Idaho Mountains. - Warming and dry Wednesday through Monday.

SHORT TERM /Through Wednesday Night/

Issued 229 PM MDT MON JUN 8 2026 A cold front is advancing eastward across Oregon, preceded by extensive mid-level cloudiness. Ahead of the front, a very dry air mass is in place, with humidity values near 10 percent through much of the Snake Plain, amidst winds gusting to 20-30 mph. Scattered to widespread showers will develop through this evening first across central Oregon, reaching the Treasure Valley after around 9 PM MDT. Although coverage will be high, rainfall amounts and intensity will be limited by how dry the sub-cloud layer is. In fact, the 18Z BOI precipitable water reading of 0.43" is close to the 25th percentile for the date. QPF amounts are generally expected to range between 0.1-0.25" across the Snake Plain, and up to 0.25-0.5" in the Idaho Mountains. There's a 10% chance of 1" of rain occurring in McCall and over the West-Central Mountains.

By Tuesday morning, the cold front will advance eastward, but a more unstable air mass will take hold and support isolated thunderstorm development over the central Idaho Mountains - especially over Valley County. Otherwise, breezy conditions will occur from southeast Oregon into southern idaho, wind gusts approaching 30-40 mph during the afternoon. Temperatures will also be 5-10 degrees below normal through Wednesday. Near- freezing temperatures are possible Wednesday and Thursday morning in parts of southeast Oregon (including Burns and Baker City), and higher elevation valleys in Idaho (including McCall and the Camas Prairie). In fact, a dusting of snow is also possible across the mountains of Valley County as snow levels fall to around 5800 feet.

LONG TERM /Thursday through Monday/

Issued 229 PM MDT MON JUN 8 2026 will build over the Pacific Northwest bringing dry weather and a warming trend. Temperatures will be near normal on Thursday and then warm to around 10 degrees above normal through the upcoming weekend. Skies will be mostly clear through the period with no precipitation expected. Winds will be light and variable.

AVIATION /00Z Tuesday through Wednesday/

Issued 624 PM MDT MON JUN 8 2026

A cold front will move from west to east through the area tonight. Rain with MVFR ceilings will accompany the front. Snow levels: 7-9 kft MSL. Precipitation will gradually end for most sites after 10Z in Oregon and after 14Z in Idaho, however precipitation, lower ceilings, and mountain obscuration will remain around KBKE, KMYL, and KTWF/KJER through the afternoon Tuesday. Surface winds: SW-NW 15 to 20 kts . Winds aloft at 10 kft: W-SW 25 to 40 kts.

KBOI...Generally VFR. A cold front will pass through Boise tonight around 04Z with a period of rain and MVFR ceilings possible (10-20% chance) from 04Z-10Z tonight. Surface winds: W-NW 10-15 kt with gusts 20-25 kt, becoming light and variable overnight.

BOI WATCHES/WARNINGS/ADVISORIES

ID...None.

OR...None.