St. Joseph, Illinois Weather
Cicadas claim the scorching afternoon. Day 14 of summer. Read this microseason across nine climate regions →
St. Joseph weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Rain54%0.21″90°70°—
- SundayJul 5Light Drizzle22%0.02″84°69°-6°
- MondayJul 6Light Drizzle15%—82°67°-2°
- TuesdayJul 7Partly Cloudy——81°61°-1°
- WednesdayJul 8Clear——82°61°+1°
- ThursdayJul 9Drizzle41%0.02″84°69°+2°
- FridayJul 10Light Drizzle41%—78°71°-6°
AQI 30 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±3 points). Ozone at AQI 39 now. With UV 6.5 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 24 around 1 PM.
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 39 now. With UV 6.5 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 24 around 1 PM.
- Present
- AQI 39
- UV peak
- 6.5 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 24
PM × Wind × Precip
PM2.5 at 6.0 µg/m³ (AQI 33) with a 0.91 fine-to-coarse ratio and 6 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.91
- 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
- 10:47 PM
- Moonset
- 9:58 AM
- In sign
- ♓︎ Pisces
Cicadas claim the scorching afternoon
St. Joseph at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: April 17 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
16-Day Forecast — St. Joseph
- Sat90°70°54%
- Sun84°69°22%
- Mon82°67°15%
- Tue81°61°4%
- Wed82°61°4%
- Thu84°69°41%
- Fri78°71°41%
- Sat83°66°12%
- Sun71°58°8%
- Mon71°57°7%
- Tue77°59°10%
- Wed80°63°19%
- Thu82°65°20%
- Fri81°69°29%
- Sat85°71°29%
- Sun81°71°39%
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 — St. Joseph
SPC has placed St. Joseph 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 St. Joseph
- 61873