St. Charles, South Dakota Weather
Prairie lightning bugs rise. Day 76 of spring. Read this microseason across nine climate regions →
St. Charles weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Thunderstorm57%0.71″83°59°—
- ThursdayJun 4Rain44%0.26″80°62°-3°
- FridayJun 5Light Drizzle43%0.02″82°61°+2°
- SaturdayJun 6Clear——89°60°+7°
- SundayJun 7Overcast20%—89°64°0°
- MondayJun 8Light Drizzle33%—93°62°+4°
- TuesdayJun 9Light Drizzle30%—90°65°-3°
Ozone at AQI 45 — peak already passed at 1 PM under clear skies. AQI flat over the last 6 hours (within ±3 points). Levels should ease through evening.
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 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 45
- UV peak
- 1.2 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 45
PM × Wind × Precip
PM2.5 at 5.5 µg/m³, PM10 at 6.6 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.83
- 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).
The higher the clouds, the finer the weather.
- Moonrise
- 4:42 AM
- Moonset
- 1:24 PM
- In sign
- ♑︎ Capricorn
Prairie lightning bugs rise
St. Charles 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
Peak growing season
As of June 3, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — St. Charles
SPC has placed St. Charles in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWSLGTSlight Risk
- DAY 3MRGLMarginal Risk
Scattered severe storms possible. A few tornadoes, hail, and damaging wind gusts possible.
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.