Brooklyn, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Brooklyn, a village in St. Clair County, Illinois.
Today
99°F
Partly Sunny
Partly sunny, with a high near 99. Heat index values as high as 102. Southwest wind around 8 mph.
7-day forecast for Brooklyn
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 99°F | Partly Sunny | 8 mph SW | 2% |
| Tonight | 75°F | Partly Cloudy | 5 mph SW | 4% |
| Sunday | 95°F | Chance Rain Showers then Slight Chance Showers And Thunderstorms | 3 to 7 mph W | 30% |
| Sunday Night | 69°F | Showers And Thunderstorms Likely | 5 to 9 mph NE | 62% |
| Monday | 80°F | Showers And Thunderstorms Likely | 6 to 10 mph NE | 64% |
| Monday Night | 61°F | Chance Showers And Thunderstorms | 7 to 10 mph NE | 50% |
| Tuesday | 73°F | Slight Chance Rain Showers then Partly Sunny | 12 mph N | 19% |
| Tuesday Night | 56°F | Mostly Cloudy | 5 to 12 mph N | 5% |
| Wednesday | 75°F | Mostly Sunny | 9 mph N | 1% |
| Wednesday Night | 57°F | Partly Cloudy | 3 to 9 mph N | 0% |
| Thursday | 78°F | Mostly Sunny | 3 to 7 mph N | 1% |
| Thursday Night | 60°F | Partly Cloudy | 2 to 7 mph NE | 3% |
| Friday | 79°F | Partly Sunny | 2 to 7 mph NE | 6% |
| Friday Night | 60°F | Partly Cloudy | 3 to 7 mph NE | 6% |
Forecast source: National Weather Service (api.weather.gov) for Brooklyn (38.654, -90.168). Updated through the day.
Growing snapshot for Brooklyn
Last spring frost
Apr 1
First fall frost
Nov 4
Growing season
218 days
Hardiness zone
7a
More local growing data for Brooklyn: nearby ZIP 62059 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Belleville
Cahokia Heights
Caseyville
Darmstadt
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East St. Louis
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Fairview Heights
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Floraville
Freeburg
Lebanon
Lenzburg
Marissa
Mascoutah
Millstadt
New Athens
O'Fallon
Paderborn
Rentchler
Sauget
Scott AFB
Shiloh
Smithton
St. Libory
Summerfield
Swansea
Washington Park
Climate data from the nearest NOAA station, St Louis Sci Ctr, Mo (5.5 mi from Brooklyn). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.