Sinai, South Dakota Weather
Prairie lightning bugs rise. Day 78 of spring. Read this microseason across nine climate regions →
Sinai weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Heavy Showers75%0.84″80°62°—
- FridayJun 5Rain25%0.32″81°60°+1°
- SaturdayJun 6Clear——85°60°+4°
- SundayJun 7Overcast26%—88°63°+3°
- MondayJun 8Light Drizzle31%—88°64°0°
- TuesdayJun 9Thunderstorm23%—91°64°+3°
- WednesdayJun 10Thunderstorm15%—99°71°+8°
Ozone at AQI 49 now. AQI up 10 over the last 6 hours (gradual rise). With UV 0.4 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 12 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 49 now. With UV 0.4 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 12 by mid-afternoon.
- Present
- AQI 49
- UV peak
- 0.4 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 12
PM × Wind × Precip
PM2.5 at 6.2 µg/m³, PM10 at 7.3 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.85
- Wind
- light
- 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
- 5:41 AM
- Moonset
- 3:25 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Sinai at a glance
- Today vs. normal: 70°F — typical for the season
- Last frost: May 11 (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 — Sinai
SPC has placed Sinai 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.