Castalia, Iowa Weather
Prairie lightning bugs rise. Day 77 of spring. Read this microseason across nine climate regions →
Castalia weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Light Rain47%0.11″81°57°—
- FridayJun 5Showers61%—78°65°-3°
- SaturdayJun 6Light Showers34%—81°61°+3°
- SundayJun 7Drizzle28%—81°62°0°
- MondayJun 8Light Showers57%—78°63°-3°
- TuesdayJun 9Light Drizzle33%—78°66°0°
- WednesdayJun 10Clear15%—91°69°+13°
PM2.5 at 8.2 µg/m³, PM10 at 9.1 µg/m³ — typical background levels with no transport signature. AQI down 22 over the last 6 hours — air quality is improving sharply.
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 41 now. With UV 3.3 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 13 by mid-afternoon.
- Present
- AQI 41
- UV peak
- 3.3 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 13
PM × Wind × Precip
PM2.5 at 8.2 µg/m³, PM10 at 9.1 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.90
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- background
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
- 4:47 AM
- Moonset
- 1:59 PM
- In sign
- ♑︎ Capricorn
Prairie lightning bugs rise
Castalia at a glance
- Today vs. normal: 12°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 — Castalia
SPC has placed Castalia in the Slight Risk category for severe thunderstorms tomorrow.
- TODAYMRGLMarginal Risk
- TOMORROWSLGTSlight Risk
- 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.