Eureka, South Dakota Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Eureka weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Partly Cloudy——87°59°—
- SundayJul 5Clear——91°61°+4°
- MondayJul 6Drizzle55%—99°68°+8°
- TuesdayJul 7T-storm w/ Hail79%0.02″81°63°-18°
- WednesdayJul 8Light Drizzle79%—80°59°-1°
- ThursdayJul 9Drizzle21%—70°60°-10°
- FridayJul 10Light Drizzle21%—70°57°0°
AQI 39 (Good), driven by PM2.5. AQI down 5 over the last 6 hours (gradual decline). PM2.5 at 8.6 µg/m³ (AQI 48) with a 0.81 fine-to-coarse ratio and 3 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 6.8 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 43 around 1 PM.
- Present
- AQI 47
- UV peak
- 6.8 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 43
PM × Wind × Precip
PM2.5 at 8.6 µg/m³ (AQI 48) with a 0.81 fine-to-coarse ratio and 3 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
- 11:43 PM
- Moonset
- 10:39 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Eureka at a glance
- Today vs. normal: 18°F above the seasonal normal for this latitude
- Last frost: May 21 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 57437
16-Day Forecast — Eureka
- Sat87°59°4%
- Sun91°61°0%
- Mon99°68°55%
- Tue81°63°79%
- Wed80°59°79%
- Thu70°60°21%
- Fri70°57°21%
- Sat79°55°19%
- Sun84°58°7%
- Mon88°61°8%
- Tue97°66°12%
- Wed100°69°12%
- Thu90°69°16%
- Fri78°63°24%
- Sat82°58°19%
- Sun88°57°17%
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 — Eureka
SPC has placed Eureka in the Marginal Risk category for severe thunderstorms day after tomorrow.
- TODAYTSTMGeneral Thunderstorms
- 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 Eureka
- 57437