Tiffin, Iowa Weather
Prairie lightning bugs rise. Day 77 of spring. Read this microseason across nine climate regions →
Tiffin weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Light Drizzle27%0.02″86°58°—
- FridayJun 5Thunderstorm79%1.7″80°63°-6°
- SaturdayJun 6Heavy Showers72%0.46″84°65°+4°
- SundayJun 7Showers43%—84°69°0°
- MondayJun 8Showers55%0.17″81°68°-3°
- TuesdayJun 9Thunderstorm36%—81°68°0°
- WednesdayJun 10Thunderstorm19%—92°73°+11°
Ozone at AQI 44. AQI down 27 over the last 6 hours — air quality is improving sharply. Overcast through the UV peak window (cloud cover ~85%) — afternoon ozone should stay flat.
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 44. Overcast through the UV peak window (cloud cover ~85%) — afternoon ozone should stay flat.
- Present
- AQI 44
- UV peak
- 3.3 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 10
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
- 4:42 AM
- Moonset
- 2:04 PM
- In sign
- ♑︎ Capricorn
Prairie lightning bugs rise
Tiffin at a glance
- Today vs. normal: 12°F below the seasonal normal for this latitude
- Last frost: April 26 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 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 — Tiffin
SPC has placed Tiffin in the Slight Risk category for severe thunderstorms tomorrow.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWSLGTSlight Risk
- DAY 3MRGLMarginal 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.