Plainfield, Indiana Weather
Fireflies pulse through the magnolias. Day 77 of spring. Read this microseason across nine climate regions →
Plainfield weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——85°57°—
- FridayJun 5Overcast10%—87°63°+2°
- SaturdayJun 6Showers55%—81°62°-6°
- SundayJun 7Showers55%—83°67°+2°
- MondayJun 8Drizzle26%—78°68°-5°
- TuesdayJun 9Light Drizzle28%0.06″73°68°-5°
- WednesdayJun 10Heavy Drizzle23%0.04″79°68°+6°
Ozone at AQI 41 now. AQI down 15 over the last 6 hours — air quality is improving sharply. With UV 3.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 18 by mid-afternoon.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 6 AM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 41 now. With UV 3.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 18 by mid-afternoon.
- Present
- AQI 41
- UV peak
- 3.3 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 18
PM × Wind × Precip
PM2.5 at 6.4 µg/m³ (AQI 36) with a 0.91 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.91
- 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).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 4:13 AM
- Moonset
- 1:48 PM
- In sign
- ♑︎ Capricorn
Fireflies pulse through the magnolias
Plainfield at a glance
- Today vs. normal: 12°F below the seasonal normal for this latitude
- Last frost: April 14 (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 — Plainfield
SPC has placed Plainfield in the General Thunderstorms category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWNONENo severe risk
- 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.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
Plainfield's warmest month is July (~74°F mean) and its coldest is January (~27°F). Rainfall peaks in June (5.4 inches) and bottoms out in February (2.3 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 27° | 3.1″ | 6 |
| February | 30° | 2.3″ | 5 |
| March | 40° | 3.7″ | 8 |
| April | 52° | 4.5″ | 8 |
| May | 62° | 5.0″ | 9 |
| June | 71° | 5.4″ | 8 |
| July | 74° | 3.9″ | 6 |
| August | 73° | 3.6″ | 5 |
| September | 66° | 3.2″ | 5 |
| October | 54° | 3.2″ | 6 |
| November | 42° | 3.4″ | 6 |
| December | 32° | 3.3″ | 7 |
Regional context
Plainfield sits within a humid subtropical climate region — a cohort that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Indianapolis, IN, Evansville, IN, Lafayette, IN, Bloomington, IN, Fishers, IN.
Frequently asked
- When does it freeze in Plainfield?
- Plainfield's last spring frost typically falls around mid-April, and the first fall frost arrives around mid-November.
- What is the rainy season in Plainfield?
- June is the wettest month with about 5.4 inches of rain on average; the city receives roughly 45 inches annually.
- What is the warmest month in Plainfield?
- July is typically warmest, averaging about 74°F.
- What is the coldest month in Plainfield?
- January is typically coldest, averaging about 27°F.
- When can I start a vegetable garden in Plainfield?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-April); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Plainfield get?
- Plainfield averages about 79 rainy days per year.
- What hardiness zone is Plainfield?
- Plainfield's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
Plainfield, Indiana sits in a humid subtropical climate zone. January means hover near 27°F while July averages 74°F — a 47°F seasonal swing.
Across the year, Plainfield receives about 45 inches of precipitation spread over roughly 79 rainy days.
The rhythm of the year is set by latitude (39.7°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.