Grinnell, Iowa Weather
Toward the solstice glow. Day 88 of spring. Read this microseason across nine climate regions →
Grinnell weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 15Overcast——77°50°—
- TuesdayJun 16Heavy Drizzle21%0.05″72°58°-5°
- WednesdayJun 17T-storm w/ Hvy Hail92%—83°59°+11°
- ThursdayJun 18Overcast——71°52°-12°
- FridayJun 19Overcast——73°51°+2°
- SaturdayJun 20Light Drizzle27%0.02″73°57°0°
- SundayJun 21T-storm w/ Hail49%0.12″81°63°+8°
AQI 33 (Good), driven by Ozone. AQI up 8 over the last 6 hours (gradual rise). Ozone at AQI 46 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
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 46 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 46
- UV peak
- 3.1 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 46
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
- 5:37 AM
- Moonset
- 9:06 PM
- In sign
- ♋︎ Cancer
Toward the solstice glow
Grinnell at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: April 26 (climatological average for this latitude)
- Microseason: Jun 11–15
- Planting window: Stake and prune tomato suckers. Watch for squash vine borers.
16-Day Forecast — Grinnell
- Mon77°50°1%
- Tue72°58°21%
- Wed83°59°92%
- Thu71°52°6%
- Fri73°51°1%
- Sat73°57°27%
- Sun81°63°49%
- Mon64°61°29%
- Tue67°58°7%
- Wed77°61°11%
- Thu77°58°15%
- Fri76°59°18%
- Sat75°65°33%
- Sun74°61°30%
- Mon68°57°39%
- Tue71°53°31%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of June 15, 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 — Grinnell
SPC has placed Grinnell in the Slight Risk category for severe thunderstorms day after tomorrow.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3SLGTSlight Risk
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 Grinnell
- 50112