Merrillville, IN Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Merrillville, a town in Lake County, Indiana.
Today
84°F
Sunny
Sunny, with a high near 84. South southwest wind 5 to 10 mph.
7-day forecast for Merrillville
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Sunny | 5 to 10 mph SSW | 0% |
| Tonight | 64°F | Partly Cloudy | 5 mph SSW | 1% |
| Wednesday | 82°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 5 mph SW | 36% |
| Wednesday Night | 65°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 0 to 5 mph WSW | 88% |
| Thursday | 78°F | Rain Showers then Chance Showers And Thunderstorms | 0 to 5 mph WSW | 88% |
| Thursday Night | 62°F | Chance Showers And Thunderstorms | 0 to 5 mph ESE | 53% |
| Friday | 81°F | Mostly Sunny | 0 to 5 mph SW | 7% |
| Friday Night | 63°F | Partly Cloudy | 0 mph | 8% |
| Saturday | 84°F | Mostly Sunny | 0 to 5 mph SSW | 9% |
| Saturday Night | 68°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 5 mph SSW | 16% |
| Sunday | 86°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 5 to 10 mph SW | 16% |
| Sunday Night | 69°F | Chance Showers And Thunderstorms | 5 to 10 mph SSW | 39% |
| Monday | 86°F | Chance Rain Showers then Slight Chance Showers And Thunderstorms | 5 to 10 mph SW | 39% |
| Monday Night | 68°F | Chance Showers And Thunderstorms | 5 mph WSW | 46% |
Forecast source: National Weather Service (api.weather.gov) for Merrillville (41.473, -87.318). Updated through the day.
Growing snapshot for Merrillville
Last spring frost
Apr 22
First fall frost
Oct 25
Growing season
185 days
Hardiness zone
6a
More local growing data for Merrillville: nearby ZIP 46410 weather · frost dates · planting calendar · Indiana frost dates
Nearby towns & communities
Cedar Lake
Crown Point
Dyer
East Chicago
Gary
Griffith
Hammond
Highland
Hobart
Lake Dalecarlia
Lake Station
Leroy
Lowell
Munster
New Chicago
Ross
Schererville
Schneider
Shelby
St. John
Whiting
Winfield
Climate data from the nearest NOAA station, Valparaiso Wtr Wks, In (15.5 mi from Merrillville). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.