Harrison, South Dakota Weather
Prairie lightning bugs rise. Day 77 of spring. Read this microseason across nine climate regions →
Harrison weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast60%—84°63°—
- FridayJun 5Light Rain41%0.17″85°63°+1°
- SaturdayJun 6Clear——89°62°+4°
- SundayJun 7Overcast20%—89°67°0°
- MondayJun 8Showers23%0.06″96°66°+7°
- TuesdayJun 9Thunderstorm23%0.73″95°66°-1°
- WednesdayJun 10Thunderstorm16%—104°74°+9°
Ozone at AQI 50 — peak already passed at 1 PM under partly cloudy skies. AQI up 17 in the last 6 hours — air quality is degrading. 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 50 — peak already passed at 1 PM under partly cloudy skies. Levels should ease through evening.
- Present
- AQI 50
- UV peak
- 1.1 at earlier today
- Sky at peak
- partly cloudy
- Projected peak
- AQI 50
PM × Wind × Precip
PM2.5 at 4.5 µg/m³, PM10 at 5.5 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.82
- 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).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 5:16 AM
- Moonset
- 2:26 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Harrison at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: May 7 (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 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 — Harrison
SPC has placed Harrison in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3NONENo severe 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.