St. John, Indiana Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
St. John weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Heavy Rain75%2.7″82°68°—
- SundayJul 5Foggy18%—76°66°-6°
- MondayJul 6Overcast——81°65°+5°
- TuesdayJul 7Overcast——82°63°+1°
- WednesdayJul 8Partly Cloudy12%—81°62°-1°
- ThursdayJul 9Light Drizzle28%0.04″80°67°-1°
- FridayJul 10Overcast28%—80°64°0°
AQI 39 (Good), driven by PM2.5. AQI down 5 over the last 6 hours (gradual decline). PM2.5 at 5.9 µg/m³ (AQI 33) with a 0.97 fine-to-coarse ratio and 3 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.
What's driving it
Ozone × UV × Sky
Ozone at AQI 33. Overcast through the UV peak window (cloud cover ~98%) — afternoon ozone should stay flat.
- Present
- AQI 33
- UV peak
- 0.3 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 4
PM × Wind × Precip
PM2.5 at 5.9 µg/m³ (AQI 33) with a 0.97 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.97
- 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).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 10:47 PM
- Moonset
- 9:54 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
St. John at a glance
- Today vs. normal: 69°F — typical for the season
- Last frost: April 25 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
16-Day Forecast — St. John
- Sat82°68°75%
- Sun76°66°18%
- Mon81°65°4%
- Tue82°63°3%
- Wed81°62°12%
- Thu80°67°28%
- Fri80°64°28%
- Sat81°62°16%
- Sun72°62°8%
- Mon73°61°9%
- Tue77°62°10%
- Wed82°63°13%
- Thu84°66°29%
- Fri78°70°27%
- Sat86°69°11%
- Sun86°70°29%
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. John
SPC has placed St. John in the Marginal Risk category for severe thunderstorms today.
- TODAYMRGLMarginal Risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3TSTMGeneral Thunderstorms
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.
ZIP codes in St. John
- 46373
- 46311