Helena, Montana Weather
Pikas hayfeeding in granite peaks. Day 78 of spring. Read this microseason across nine climate regions →
Helena weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast21%—73°54°—
- FridayJun 5Overcast——86°49°+13°
- SaturdayJun 6Overcast33%—72°54°-14°
- SundayJun 7Light Snow46%0.15″60°42°-12°
- MondayJun 8Light Drizzle19%—72°43°+12°
- TuesdayJun 9Light Drizzle62%0.03″67°49°-5°
- WednesdayJun 10Light Drizzle64%0.07″69°52°+2°
AQI 49 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±4 points). Ozone at AQI 45 now. With UV 0.1 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 11 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 45 now. With UV 0.1 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 11 by mid-afternoon.
- Present
- AQI 45
- UV peak
- 0.1 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 11
PM × Wind × Precip
PM2.5 at 5.4 µg/m³, PM10 at 6.6 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.82
- Wind
- light
- 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).
The higher the clouds, the finer the weather.
- Moonrise
- 6:49 AM
- Moonset
- 4:21 PM
- In sign
- ♒︎ Aquarius
Pikas hayfeeding in granite peaks
Helena at a glance
- Today vs. normal: 68°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 5, 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.