Helena, Montana Weather
Pikas hayfeeding in granite peaks. Day 77 of spring. Read this microseason across nine climate regions →
Helena weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast21%—72°54°—
- FridayJun 5Overcast——82°49°+10°
- SaturdayJun 6Overcast24%—80°54°-2°
- SundayJun 7Light Snow Shwrs42%0.25″60°44°-20°
- MondayJun 8Overcast17%—71°41°+11°
- TuesdayJun 9Light Drizzle58%0.02″71°54°0°
- WednesdayJun 10Overcast57%—78°51°+7°
Ozone at AQI 51 now. AQI up 11 over the last 6 hours (gradual rise). With UV 6.7 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 46 by mid-afternoon.
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 51 now. With UV 6.7 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 46 by mid-afternoon.
- Present
- AQI 51
- UV peak
- 6.7 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 46
PM × Wind × Precip
PM2.5 at 4.9 µg/m³, PM10 at 6.8 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.72
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
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
- 6:24 AM
- Moonset
- 3:11 PM
- In sign
- ♒︎ Aquarius
Pikas hayfeeding in granite peaks
Helena at a glance
- Today vs. normal: 70°F — typical for the season
- Last frost: May 26 (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 — Helena
SPC has placed Helena in the General Thunderstorms category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWNONENo severe risk
- 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.