Mason City, Iowa Weather
Prairie lightning bugs rise. Day 77 of spring. Read this microseason across nine climate regions →
Mason City weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Rain56%0.20″82°65°—
- FridayJun 5Overcast21%—85°64°+3°
- SaturdayJun 6Overcast13%—85°62°0°
- SundayJun 7Light Showers39%—82°67°-3°
- MondayJun 8Heavy Drizzle53%0.02″82°68°0°
- TuesdayJun 9Heavy Showers39%0.83″82°69°0°
- WednesdayJun 10Thunderstorm16%—92°70°+10°
PM scrubbed by 2 hours of recent rain — PM2.5 down to 8.4 µg/m³, PM10 to 9.4 µg/m³. AQI up 8 over the last 6 hours (gradual rise).
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 — peak already passed at 1 PM under overcast skies. Levels should ease through evening.
- Present
- AQI 45
- UV peak
- 0.5 at earlier today
- Sky at peak
- overcast
- Projected peak
- AQI 45
PM × Wind × Precip
PM scrubbed by 2 hours of recent rain — PM2.5 down to 8.4 µg/m³, PM10 to 9.4 µg/m³.
- PM2.5/PM10
- 0.89
- Wind
- light
- Recent rain
- 2h in last 6h
- Pattern
- washed out
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
- 4:53 AM
- Moonset
- 2:05 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Mason City at a glance
- Today vs. normal: 4°F below the seasonal normal for this latitude
- Last frost: May 5 (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 — Mason City
SPC has placed Mason City in the Slight Risk category for severe thunderstorms tomorrow.
- TODAYMRGLMarginal Risk
- TOMORROWSLGTSlight Risk
- 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.