Groton, South Dakota Weather
Prairie lightning bugs rise. Day 78 of spring. Read this microseason across nine climate regions →
Groton weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast22%—80°61°—
- FridayJun 5Overcast21%—83°62°+3°
- SaturdayJun 6Mostly Clear——90°60°+7°
- SundayJun 7Thunderstorm18%—89°69°-1°
- MondayJun 8Thunderstorm29%—88°71°-1°
- TuesdayJun 9Thunderstorm22%—92°69°+4°
- WednesdayJun 10Thunderstorm22%—98°74°+6°
AQI 44 (Good), driven by Ozone. AQI up 6 over the last 6 hours (gradual rise). Ozone at AQI 34 now. With UV 0.0 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 8 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 34 now. With UV 0.0 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 8 by mid-afternoon.
- Present
- AQI 34
- UV peak
- 0.0 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 8
PM × Wind × Precip
PM2.5/PM10 ratio 0.64 with 10 mph wind — characteristic of long-range haze transport rather than a local source.
- PM2.5/PM10
- 0.64
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- transport
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
- 5:49 AM
- Moonset
- 3:26 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Groton at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: May 19 (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 5, 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 — Groton
SPC has placed Groton in the Marginal Risk category for severe thunderstorms today.
- TODAYMRGLMarginal Risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3NONENo severe 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.