San Jose, Illinois Weather
Cicadas claim the scorching afternoon. Day 14 of summer. Read this microseason across nine climate regions →
San Jose weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Light Showers56%0.77″88°69°—
- SundayJul 5Overcast15%—83°70°-5°
- MondayJul 6Partly Cloudy——83°66°0°
- TuesdayJul 7Mostly Clear——81°61°-2°
- WednesdayJul 8Light Drizzle——84°63°+3°
- ThursdayJul 9Drizzle42%0.04″83°70°-1°
- FridayJul 10Light Drizzle42%—78°68°-5°
AQI 26 (Good), driven by PM2.5. AQI down 8 over the last 6 hours (gradual decline). PM2.5 at 8.6 µg/m³ (AQI 48) with a 0.90 fine-to-coarse ratio and 5 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 during the projected peak around 10 PM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 35. Overcast through the UV peak window (cloud cover ~68%) — afternoon ozone should stay flat.
- Present
- AQI 35
- UV peak
- 4.4 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 10
PM × Wind × Precip
PM2.5 at 8.6 µg/m³ (AQI 48) with a 0.90 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.90
- Wind
- light
- 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
- 10:53 PM
- Moonset
- 10:04 AM
- In sign
- ♓︎ Pisces
Cicadas claim the scorching afternoon
San Jose at a glance
- Today vs. normal: 10°F above the seasonal normal for this latitude
- Last frost: April 18 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 62682
16-Day Forecast — San Jose
- Sat88°69°56%
- Sun83°70°15%
- Mon83°66°8%
- Tue81°61°3%
- Wed84°63°4%
- Thu83°70°42%
- Fri78°68°42%
- Sat83°66°14%
- Sun71°59°7%
- Mon74°57°7%
- Tue76°60°8%
- Wed79°63°16%
- Thu82°64°20%
- Fri82°69°29%
- Sat85°69°32%
- Sun86°72°35%
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 — San Jose
SPC has placed San Jose in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3TSTMGeneral Thunderstorms
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.
ZIP codes in San Jose
- 62682