Princeton, Iowa Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Princeton weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Heavy Rain37%0.45″83°67°—
- SundayJul 5Overcast13%—84°67°+1°
- MondayJul 6Clear——79°63°-5°
- TuesdayJul 7Overcast——80°60°+1°
- WednesdayJul 8Light Showers10%—82°64°+2°
- ThursdayJul 9Showers41%—78°70°-4°
- FridayJul 10Light Drizzle20%—79°67°+1°
AQI 31 (Good), driven by PM2.5. AQI up 5 over the last 6 hours (gradual rise). PM2.5 at 10.7 µg/m³ (AQI 54) with a 0.73 fine-to-coarse ratio and 2 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 45. Overcast through the UV peak window (cloud cover ~83%) — afternoon ozone should stay flat.
- Present
- AQI 45
- UV peak
- 5.3 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 16
PM × Wind × Precip
PM2.5 at 10.7 µg/m³ (AQI 54) with a 0.73 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.73
- 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
- 10:58 PM
- Moonset
- 10:06 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Princeton at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: April 26 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 52768
16-Day Forecast — Princeton
- Sat83°67°37%
- Sun84°67°13%
- Mon79°63°2%
- Tue80°60°1%
- Wed82°64°10%
- Thu78°70°41%
- Fri79°67°20%
- Sat73°61°19%
- Sun76°58°8%
- Mon74°58°8%
- Tue78°58°8%
- Wed77°59°29%
- Thu81°64°18%
- Fri78°69°32%
- Sat78°62°26%
- Sun73°58°26%
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 — Princeton
SPC includes Princeton in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3NONENo severe risk
Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.
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 Princeton
- 52753
- 52768