Williams Bay, Wisconsin Weather
Fireflies rise from the lawn. Day 77 of spring. Read this microseason across nine climate regions →
Williams Bay weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——81°48°—
- ThursdayJun 4Overcast——86°57°+5°
- FridayJun 5Drizzle82%0.04″77°67°-9°
- SaturdayJun 6Showers50%0.15″85°64°+8°
- SundayJun 7Foggy——78°60°-7°
- MondayJun 8Light Showers38%0.03″77°63°-1°
- TuesdayJun 9Drizzle29%0.03″82°69°+5°
PM2.5 at 12.2 µg/m³ (AQI 57) with a 0.90 fine-to-coarse ratio and 1 mph wind — combustion smoke trapped in calm air, not road dust. AQI up 9 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 30. Overcast through the UV peak window (cloud cover ~67%) — afternoon ozone should stay flat.
- Present
- AQI 30
- UV peak
- 0.0 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 4
PM × Wind × Precip
PM2.5 at 12.2 µg/m³ (AQI 57) with a 0.90 fine-to-coarse ratio and 1 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.90
- 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).










































A summer fog for fair, a winter fog for rain.
- Moonrise
- 4:32 AM
- Moonset
- 1:47 PM
- In sign
- ♑︎ Capricorn
Fireflies rise from the lawn
Williams Bay at a glance
- Today vs. normal: 9°F below the seasonal normal for this latitude
- Last frost: May 1 (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 — Williams Bay
SPC has placed Williams Bay in the Marginal Risk category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWTSTMGeneral Thunderstorms
- 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.