Chinook, Montana Weather
Pikas hayfeeding in granite peaks. Day 77 of spring. Read this microseason across nine climate regions →
Chinook weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Rain21%0.28″76°49°—
- FridayJun 5Overcast——78°51°+2°
- SaturdayJun 6Showers41%0.48″81°54°+3°
- SundayJun 7Rain41%0.49″61°47°-20°
- MondayJun 8Overcast26%—73°45°+12°
- TuesdayJun 9Light Drizzle26%0.01″78°57°+5°
- WednesdayJun 10Overcast46%—79°57°+1°
Ozone at AQI 45 — peak already passed at 1 PM under clear skies. AQI up 7 over the last 6 hours (gradual rise). Levels should ease through evening.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 45 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 45
- UV peak
- 2.1 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 45
PM × Wind × Precip
PM scrubbed by 3 hours of recent rain — PM2.5 down to 6.6 µg/m³, PM10 to 8.7 µg/m³.
- PM2.5/PM10
- 0.76
- Wind
- light
- Recent rain
- 3h in last 6h
- Pattern
- washed out
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 6:21 AM
- Moonset
- 2:51 PM
- In sign
- ♒︎ Aquarius
Pikas hayfeeding in granite peaks
Chinook at a glance
- Today vs. normal: 10°F above the seasonal normal for this latitude
- Last frost: June 7 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Warm-season window is open
As of June 4, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
SPC Convective Outlook
Storm Prediction Center — Chinook
SPC has placed Chinook in the General Thunderstorms category for severe thunderstorms today.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3TSTMGeneral Thunderstorms
Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.