St. Charles, Idaho Weather
Pikas hayfeeding in granite peaks. Day 77 of spring. Read this microseason across nine climate regions →
St. Charles weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——74°54°—
- FridayJun 5Clear——77°51°+3°
- SaturdayJun 6Overcast——80°54°+3°
- SundayJun 7Light Drizzle15%—63°45°-17°
- MondayJun 8Overcast——75°44°+12°
- TuesdayJun 9Overcast13%—71°50°-4°
- WednesdayJun 10Light Drizzle23%0.01″71°47°0°
Ozone at AQI 34 now. AQI flat over the last 6 hours (within ±4 points). With UV 3.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 15 by mid-afternoon.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 7 AM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 34 now. With UV 3.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 15 by mid-afternoon.
- Present
- AQI 34
- UV peak
- 3.3 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 15
PM × Wind × Precip
PM2.5 at 5.2 µg/m³ (AQI 29) with a 0.69 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.69
- Wind
- calm
- 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
- 3:24 PM
- In sign
- ♑︎ Capricorn
Pikas hayfeeding in granite peaks
St. Charles at a glance
- Today vs. normal: 15°F below the seasonal normal for this latitude
- Last frost: April 29 (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.