Castalia, Iowa Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Castalia weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Drizzle22%0.04″83°67°—
- SundayJul 5Heavy Rain19%1.6″79°67°-4°
- MondayJul 6Light Drizzle——79°63°0°
- TuesdayJul 7Light Drizzle——80°63°+1°
- WednesdayJul 8T-storm w/ Hail42%0.13″80°63°0°
- ThursdayJul 9Light Showers45%—74°66°-6°
- FridayJul 10Overcast10%—77°62°+3°
AQI 40 (Good), driven by PM2.5. AQI up 9 over the last 6 hours (gradual rise). PM2.5 at 9.9 µg/m³ (AQI 52) with a 0.77 fine-to-coarse ratio and 4 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 40. Overcast through the UV peak window (cloud cover ~96%) — afternoon ozone should stay flat.
- Present
- AQI 40
- UV peak
- 6.2 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 17
PM × Wind × Precip
PM2.5 at 9.9 µg/m³ (AQI 52) with a 0.77 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.77
- 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
- 11:06 PM
- Moonset
- 10:09 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Castalia at a glance
- Today vs. normal: 11°F above the seasonal normal for this latitude
- Last frost: May 5 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 52133
16-Day Forecast — Castalia
- Sat83°67°22%
- Sun79°67°19%
- Mon79°63°1%
- Tue80°63°7%
- Wed80°63°42%
- Thu74°66°45%
- Fri77°62°10%
- Sat80°60°10%
- Sun68°57°10%
- Mon73°52°8%
- Tue77°59°5%
- Wed76°61°16%
- Thu76°67°19%
- Fri82°66°26%
- Sat85°68°23%
- Sun83°69°32%
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 — Castalia
SPC includes Castalia in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3TSTMGeneral Thunderstorms
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 Castalia
- 52133