Custer, Montana Weather
Pikas hayfeeding in granite peaks. Day 77 of spring. Read this microseason across nine climate regions →
Custer weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——73°51°—
- ThursdayJun 4Overcast19%—76°56°+3°
- FridayJun 5Clear——88°55°+12°
- SaturdayJun 6Light Drizzle10%—98°64°+10°
- SundayJun 7Light Drizzle30%—74°58°-24°
- MondayJun 8Overcast24%—86°50°+12°
- TuesdayJun 9Overcast19%—86°64°0°
Ozone at AQI 33. AQI flat over the last 6 hours (within ±3 points). Overcast through the UV peak window (cloud cover ~94%) — afternoon ozone should stay flat.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 6 AM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 33. Overcast through the UV peak window (cloud cover ~94%) — afternoon ozone should stay flat.
- Present
- AQI 33
- UV peak
- 0.0 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 4
PM × Wind × Precip
PM2.5 at 4.6 µg/m³ (AQI 26) with a 0.84 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.84
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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
- 6:03 AM
- Moonset
- 2:54 PM
- In sign
- ♑︎ Capricorn
Pikas hayfeeding in granite peaks
Custer at a glance
- Today vs. normal: 7°F below the seasonal normal for this latitude
- Last frost: May 23 (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 — Custer
SPC has placed Custer in the Marginal Risk category for severe thunderstorms tomorrow.
- TODAYNONENo severe risk
- TOMORROWMRGLMarginal Risk
- DAY 3TSTMGeneral Thunderstorms
Isolated severe storms possible. Limited threat for hail or damaging wind.
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.