Ontario, Wisconsin Weather
Prairie lightning bugs rise. Day 78 of spring. Read this microseason across nine climate regions →
Ontario weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Drizzle63%0.05″85°54°—
- FridayJun 5Light Rain47%0.15″82°64°-3°
- SaturdayJun 6Overcast16%—83°62°+1°
- SundayJun 7Light Showers13%—77°62°-6°
- MondayJun 8Drizzle73%—72°62°-5°
- TuesdayJun 9Light Drizzle49%0.01″80°68°+8°
- WednesdayJun 10Thunderstorm14%—86°70°+6°
PM scrubbed by 3 hours of recent rain — PM2.5 down to 8.4 µg/m³, PM10 to 9.7 µg/m³. AQI up 8 over the last 6 hours (gradual rise).
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 41 now. With UV 0.1 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 10 by mid-afternoon.
- Present
- AQI 41
- UV peak
- 0.1 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 10
PM × Wind × Precip
PM scrubbed by 3 hours of recent rain — PM2.5 down to 8.4 µg/m³, PM10 to 9.7 µg/m³.
- PM2.5/PM10
- 0.87
- Wind
- breezy
- Recent rain
- 3h in last 6h
- Pattern
- washed out
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
- 5:13 AM
- Moonset
- 3:01 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Ontario at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: May 8 (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 — Ontario
SPC has placed Ontario in the Marginal Risk category for severe thunderstorms tomorrow.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWMRGLMarginal Risk
- 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.