Johnstown, Wyoming Weather
Pikas hayfeeding in granite peaks. Day 77 of spring. Read this microseason across nine climate regions →
Johnstown weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——83°52°—
- FridayJun 5Overcast——86°52°+3°
- SaturdayJun 6Overcast12%—93°56°+7°
- SundayJun 7Overcast16%—79°60°-14°
- MondayJun 8Overcast——84°51°+5°
- TuesdayJun 9Overcast——88°59°+4°
- WednesdayJun 10Drizzle—0.06″82°56°-6°
Ozone at AQI 75 now. AQI up 8 over the last 6 hours (gradual rise). With UV 8.8 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 88 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 75 now. With UV 8.8 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 88 by mid-afternoon.
- Present
- AQI 75
- UV peak
- 8.8 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 88
PM × Wind × Precip
PM10 at 41.8 µg/m³ (AQI 39) with a 0.22 fine-to-coarse ratio under 14 mph wind — coarse road or agricultural dust being kicked up.
- PM2.5/PM10
- 0.22
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- blown dust
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
- 5:56 AM
- Moonset
- 3:10 PM
- In sign
- ♒︎ Aquarius
Pikas hayfeeding in granite peaks
Johnstown at a glance
- Today vs. normal: 10°F above the seasonal normal for this latitude
- Last frost: May 5 (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.