As of 15:57 CDT

Weather in Williamson, IL

88°

Williamson, Friday, 9 October, 15:57

Clear. Feels like 85°. High 88°, low 53°.

Pressure30.00 inHg

Wind10.6 mph S

Humidity26%

Visibility6.2 mi

Dew point49°

See detailed hourly forecast

Sat, 1078° / 55°

78 °

Williamson, Saturday, 10 October

Overcast. High 78°, low 55°.

Pressure30.06 inHg

Wind7.1 mph SE

Humidity44%

Visibility6.2 mi

Dew point51°

Sun, 1183° / 53°

83 °

Williamson, Sunday, 11 October

Clear. High 83°, low 53°.

Pressure29.97 inHg

Wind2.5 mph W

Humidity45%

Visibility6.2 mi

Dew point55°

Mon, 1290° / 65°

90 °

Williamson, Monday, 12 October

Mostly clear. High 90°, low 65°.

Pressure29.91 inHg

Wind10.8 mph SW

Humidity38%

Visibility6.2 mi

Dew point57°

Tue, 1391° / 72°

91 °

Williamson, Tuesday, 13 October

Partly cloudy. High 91°, low 72°.

Pressure29.88 inHg

Wind9.3 mph W

Humidity54%

Visibility6.2 mi

Dew point68°

Wed, 1474° / 66°

0.6

74 °

Williamson, Wednesday, 14 October

Rain. High 74°, low 66°.

Pressure30.00 inHg

Wind10.7 mph NE

Humidity95%

Visibility—

Dew point72°

Thu, 1584° / 61°

0.2

84 °

Williamson, Thursday, 15 October

Light rain. High 84°, low 61°.

Pressure29.91 inHg

Wind18.5 mph SW

Humidity63%

Visibility—

Dew point64°

Fri, 1665° / 52°

0.01

65 °

Williamson, Friday, 16 October

Light rain. High 65°, low 52°.

Pressure30.15 inHg

Wind20.9 mph W

Humidity31%

Visibility—

Dew point30°

Sat, 1748° / 37°

48 °

Williamson, Saturday, 17 October

Overcast. High 48°, low 37°.

Pressure30.42 inHg

Wind20.3 mph NW

Humidity45%

Visibility—

Dew point25°

Sun, 1855° / 34°

55 °

Williamson, Sunday, 18 October

Partly cloudy. High 55°, low 34°.

Pressure30.47 inHg

Wind6.3 mph N

Humidity32%

Visibility—

Dew point22°

Mon, 1961° / 40°

61 °

Williamson, Monday, 19 October

Overcast. High 61°, low 40°.

Pressure30.39 inHg

Wind8.6 mph S

Humidity29%

Visibility—

Dew point25°

Tue, 2068° / 44°

68 °

Williamson, Tuesday, 20 October

Clear. High 68°, low 44°.

Pressure30.39 inHg

Wind6.7 mph SE

Humidity25%

Visibility—

Dew point26°

Wed, 2172° / 46°

72 °

Williamson, Wednesday, 21 October

Clear. High 72°, low 46°.

Pressure30.30 inHg

Wind8 mph S

Humidity24%

Visibility—

Dew point28°

Thu, 2276° / 50°

76 °

Williamson, Thursday, 22 October

Clear. High 76°, low 50°.

Pressure30.15 inHg

Wind9 mph W

Humidity27%

Visibility—

Dew point35°

Fri, 2377° / 53°

77 °

Williamson, Friday, 23 October

Clear. High 77°, low 53°.

Pressure30.03 inHg

Wind7.9 mph SW

Humidity28%

Visibility—

Dew point37°

Sat, 2478° / 54°

78 °

Williamson, Saturday, 24 October

Overcast. High 78°, low 54°.

Pressure30.06 inHg

Wind10.9 mph SW

Humidity21%

Visibility—

Dew point32°

About the monthly outlook

How accurate is a 30-day forecast?

The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Williamson, IL are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.

What does "above normal" mean?

We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.

Where do the 66-year records come from?

They are real temperature extremes recorded in Williamson, IL since 1960: the highest and lowest reading for each calendar date, with the year it happened.

How often is it updated?

The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.