Grafton, IL Weather Forecast
Local 7-day forecast
Sunny then Chance Showers And Thunderstorms
Track current conditions, temperature changes, wind, and the full daily outlook for Grafton, IL in one place.
A chance of showers and thunderstorms after 2pm. Sunny. High near 98, with temperatures falling to around 94 in the afternoon. Heat index values as high as 105. Southwest wind 6 to 10 mph. Chance of precipitation is 40%.
Local Weather Overview
This forecast page for Grafton, IL is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: Sep 14, 2026 8:04 AM CDT.
The active forecast window currently covers Sep 15 to Sep 20, 2026 for Grafton, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Sep 15 to Sep 20, 2026
- Latest sync
- Sep 14, 2026 8:04 AM CDT
- Forecast office
- LSX
- Source
- NOAA / NWS
Daily Outlook
This Week in Grafton
Tuesday looks like the warmest upcoming period in Grafton at 98 degrees F.
Sunday Night is the coolest period ahead with temperatures near 66 degrees F.
The strongest winds are forecast for Tuesday at about 6 to 10 mph SW.
Precipitation is mentioned in 7 upcoming forecast periods.
Forecast Details
- Last updated
- Sep 14, 2026 8:04 AM CDT
- Coverage
- 6 days
- Time zone
- America/Chicago
- Forecast office
- LSX
- Radar station
- KLSX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
A chance of showers and thunderstorms before 10pm, then a chance of showers and thunderstorms. Partly cloudy, with a low around 72. Heat index values as high as 101. Southeast wind around 5 mph. Chance of precipitation is 50%.
A chance of showers and thunderstorms before 4pm, then a slight chance of showers and thunderstorms. Mostly sunny, with a high near 96. Southeast wind 2 to 6 mph. Chance of precipitation is 50%.
A slight chance of showers and thunderstorms before 7pm. Partly cloudy, with a low around 74. Chance of precipitation is 20%.
Mostly sunny, with a high near 95.
Partly cloudy, with a low around 72.
Mostly sunny, with a high near 93.
Partly cloudy, with a low around 71.
Mostly sunny, with a high near 91.
A chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 69. Chance of precipitation is 30%.
A chance of showers and thunderstorms. Partly sunny, with a high near 87. Chance of precipitation is 30%.
A chance of showers and thunderstorms. Mostly cloudy, with a low around 66. Chance of precipitation is 30%.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Tuesday
Sep 15
|
Sunny then Chance Showers And Thunderstorms
|
98°F |
6 to 10 mph
SW
|
|
Tuesday Night
Sep 15
|
Chance Showers And Thunderstorms
|
72°F |
5 mph
SE
|
|
Wednesday
Sep 16
|
Chance Showers And Thunderstorms
|
96°F |
2 to 6 mph
SE
|
|
Wednesday Night
Sep 16
|
Slight Chance Showers And Thunderstorms then Partly Cloudy
|
74°F |
5 mph
S
|
|
Thursday
Sep 17
|
Mostly Sunny
|
95°F |
3 to 7 mph
W
|
|
Thursday Night
Sep 17
|
Partly Cloudy
|
72°F |
3 mph
NE
|
|
Friday
Sep 18
|
Mostly Sunny
|
93°F |
6 mph
SE
|
|
Friday Night
Sep 18
|
Partly Cloudy
|
71°F |
6 mph
SE
|
|
Saturday
Sep 19
|
Mostly Sunny
|
91°F |
6 to 10 mph
SW
|
|
Saturday Night
Sep 19
|
Partly Cloudy then Chance Showers And Thunderstorms
|
69°F |
8 mph
NW
|
|
Sunday
Sep 20
|
Chance Showers And Thunderstorms
|
87°F |
6 to 9 mph
SW
|
|
Sunday Night
Sep 20
|
Chance Showers And Thunderstorms
|
66°F |
5 to 9 mph
NE
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Grafton.
