Chelsea, South Dakota Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Chelsea weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Light Drizzle—0.01″88°63°—
- SundayJul 5Mostly Clear——89°63°+1°
- MondayJul 6Light Showers57%0.09″100°67°+11°
- TuesdayJul 7Heavy Showers71%0.57″93°65°-7°
- WednesdayJul 8Light Showers73%0.01″82°63°-11°
- ThursdayJul 9Light Showers15%0.24″76°61°-6°
- FridayJul 10Light Drizzle19%—75°61°-1°
AQI 50 (Good), driven by PM2.5. AQI down 5 over the last 6 hours (gradual decline). PM2.5 at 9.2 µg/m³ (AQI 51) with a 0.81 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
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 47 now. With UV 6.1 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 38 around 1 PM.
- Present
- AQI 47
- UV peak
- 6.1 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 38
PM × Wind × Precip
PM2.5 at 9.2 µg/m³ (AQI 51) with a 0.81 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.81
- 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).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 11:38 PM
- Moonset
- 10:36 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Chelsea at a glance
- Today vs. normal: 19°F above the seasonal normal for this latitude
- Last frost: May 17 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
16-Day Forecast — Chelsea
- Sat88°63°8%
- Sun89°63°2%
- Mon100°67°57%
- Tue93°65°71%
- Wed82°63°73%
- Thu76°61°15%
- Fri75°61°19%
- Sat80°56°19%
- Sun86°59°9%
- Mon88°63°8%
- Tue95°66°10%
- Wed99°67°11%
- Thu93°74°14%
- Fri79°64°20%
- Sat84°60°14%
- Sun88°57°23%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 4, 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 — Chelsea
SPC has placed Chelsea in the Marginal Risk category for severe thunderstorms today.
- TODAYMRGLMarginal Risk
- TOMORROWNONENo severe risk
- DAY 3MRGLMarginal Risk
Isolated severe storms possible. Limited threat for hail or damaging wind.
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.
ZIP codes in Chelsea
- 57465