As of 22:13 CDT

Weather in Grayslake, IL

57°Current weather

Grayslake, Wednesday, 14 October, 22:13

Overcast. Feels like 56°. High 64°, low 57°.

Pressure30.15 inHg
Wind9.2 mph NE
Humidity81%
Visibility6.2 mi
Dew point51°

Monthly outlook for Grayslake, IL: average high 62.5°, average low 49.2°. That is 3.1° above the climate normal for October. Precipitation is expected on 4 days (about 1.6 inches), against a normal of 5 days and 1.6 inches. The warmest day looks like 23 October (73.9°), the coolest 17 October (39.1°).

62.5°/49.2°
Average high / low
+3.1°
Above normal
4 / 5
Wet days / normal
1.6 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
14 October – 23 October64.1°58.2°+3.2°
24 October – 2 November60°54.4°+3.1°
3 November – 12 Novemberat normal49.4°—

October records over 66 years

86.9°3 October 2025All-time high
26.1°30 October 1988All-time low

Climate normals and records are computed from the nearest reference point — Round Lake Beach (4 mi).

Thu, 1562° / 56°0.51Rain
62 °Rain

Grayslake, Thursday, 15 October

Rain. High 62°, low 56°.

Pressure30.06 inHg
Wind8.1 mph SE
Humidity83%
Visibility6.2 mi
Dew point55°
Fri, 1657° / 44°0.04Light rain
57 °Light rain

Grayslake, Friday, 16 October

Light rain. High 57°, low 44°.

Pressure30.00 inHg
Wind16.6 mph NW
Humidity67%
Visibility5.9 mi
Dew point43°
Sat, 1754° / 39°0Clear
54 °Clear

Grayslake, Saturday, 17 October

Clear. High 54°, low 39°.

Pressure30.53 inHg
Wind4.5 mph W
Humidity50%
Visibility6.2 mi
Dew point33°
Sun, 1860° / 44°0Clear
60 °Clear

Grayslake, Sunday, 18 October

Clear. High 60°, low 44°.

Pressure30.42 inHg
Wind13.2 mph SW
Humidity51%
Visibility6.2 mi
Dew point38°
Mon, 1962° / 43°0Overcast
62 °Overcast

Grayslake, Monday, 19 October

Overcast. High 62°, low 43°.

Pressure30.39 inHg
Wind7.8 mph SW
Humidity53%
Visibility—
Dew point41°
Tue, 2066° / 45°0Clear
66 °Clear

Grayslake, Tuesday, 20 October

Clear. High 66°, low 45°.

Pressure30.36 inHg
Wind6 mph E
Humidity49%
Visibility—
Dew point42°
Wed, 2170° / 53°0Overcast
70 °Overcast

Grayslake, Wednesday, 21 October

Overcast. High 70°, low 53°.

Pressure30.30 inHg
Wind8.6 mph S
Humidity47%
Visibility—
Dew point46°
Thu, 2272° / 58°0Partly cloudy
72 °Partly cloudy

Grayslake, Thursday, 22 October

Partly cloudy. High 72°, low 58°.

Pressure30.21 inHg
Wind11.2 mph S
Humidity44%
Visibility—
Dew point46°
Fri, 2374° / 61°0.02Light rain
74 °Light rain

Grayslake, Friday, 23 October

Light rain. High 74°, low 61°.

Pressure30.00 inHg
Wind18.2 mph S
Humidity56%
Visibility—
Dew point55°
Sat, 2470° / 60°0.04Light rain
70 °Light rain

Grayslake, Saturday, 24 October

Light rain. High 70°, low 60°.

Pressure30.18 inHg
Wind9.6 mph SW
Humidity59%
Visibility—
Dew point54°
Sun, 2559° / 50°0.03Light rain
59 °Light rain

Grayslake, Sunday, 25 October

Light rain. High 59°, low 50°.

Pressure30.18 inHg
Wind10.9 mph N
Humidity58%
Visibility—
Dew point43°
Mon, 2655° / 43°0.91Rain
55 °Rain

Grayslake, Monday, 26 October

Rain. High 55°, low 43°.

Pressure30.03 inHg
Wind13 mph NW
Humidity43%
Visibility—
Dew point30°
Tue, 2759° / 44°0Clear
59 °Clear

Grayslake, Tuesday, 27 October

Clear. High 59°, low 44°.

Pressure30.15 inHg
Wind5.3 mph SW
Humidity44%
Visibility—
Dew point35°
Wed, 2859° / 45°0Overcast
59 °Overcast

Grayslake, Wednesday, 28 October

Overcast. High 59°, low 45°.

Pressure29.91 inHg
Wind6 mph SW
Humidity44%
Visibility—
Dew point35°
Thu, 2958° / 45°0Clear
58 °Clear

Grayslake, Thursday, 29 October

Clear. High 58°, low 45°.

Pressure29.94 inHg
Wind15.4 mph NW
Humidity44%
Visibility—
Dew point34°
From day 17 onward the outlook is built from 60-year climate statistics
Fri, 3056° / 43°0.09Climate normal
56 °Climate normal

Grayslake, Friday, 30 October

Climate normal for this date — 60-year average.

Average high56°
Average low43°
Average precipitation0.09 in
Chance of precipitation30%
Record high76° (2024)
Record low26° (1988)
Sat, 3154° / 43°0.12Climate normal
54 °Climate normal

Grayslake, Saturday, 31 October

Climate normal for this date — 60-year average.

Average high54°
Average low43°
Average precipitation0.12 in
Chance of precipitation42%
Record high71° (1974)
Record low28° (2019)
Sun, 0153° / 42°0.16Climate normal
53 °Climate normal

Grayslake, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high53°
Average low42°
Average precipitation0.16 in
Chance of precipitation45%
Record high71° (2016)
Record low20° (2019)
Mon, 0252° / 41°0.14Climate normal
52 °Climate normal

Grayslake, Monday, 2 November

Climate normal for this date — 60-year average.

Average high52°
Average low41°
Average precipitation0.14 in
Chance of precipitation37%
Record high72° (1961)
Record low23° (1991)
Tue, 0351° / 40°0.06Climate normal
51 °Climate normal

Grayslake, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high51°
Average low40°
Average precipitation0.06 in
Chance of precipitation30%
Record high70° (1987)
Record low17° (1991)
Wed, 0451° / 41°0.1Climate normal
51 °Climate normal

Grayslake, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high51°
Average low41°
Average precipitation0.1 in
Chance of precipitation32%
Record high69° (2022)
Record low15° (1991)
Thu, 0551° / 40°0.12Climate normal
51 °Climate normal

Grayslake, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high51°
Average low40°
Average precipitation0.12 in
Chance of precipitation28%
Record high71° (1978)
Record low20° (1991)
Fri, 0651° / 38°0.09Climate normal
51 °Climate normal

Grayslake, Friday, 6 November

Climate normal for this date — 60-year average.

Average high51°
Average low38°
Average precipitation0.09 in
Chance of precipitation30%
Record high70° (2020)
Record low22° (1991)
Sat, 0750° / 38°0.05Climate normal
50 °Climate normal

Grayslake, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high50°
Average low38°
Average precipitation0.05 in
Chance of precipitation18%
Record high68° (2020)
Record low14° (1991)
Sun, 0850° / 38°0.04Climate normal
50 °Climate normal

Grayslake, Sunday, 8 November

Climate normal for this date — 60-year average.

Average high50°
Average low38°
Average precipitation0.04 in
Chance of precipitation18%
Record high73° (2020)
Record low15° (1991)
Mon, 0950° / 38°0.11Climate normal
50 °Climate normal

Grayslake, Monday, 9 November

Climate normal for this date — 60-year average.

Average high50°
Average low38°
Average precipitation0.11 in
Chance of precipitation33%
Record high73° (2020)
Record low20° (1991)
Tue, 1049° / 37°0.11Climate normal
49 °Climate normal

Grayslake, Tuesday, 10 November

Climate normal for this date — 60-year average.

Average high49°
Average low37°
Average precipitation0.11 in
Chance of precipitation38%
Record high72° (2022)
Record low16° (2017)
Wed, 1146° / 35°0.08Climate normal
46 °Climate normal

Grayslake, Wednesday, 11 November

Climate normal for this date — 60-year average.

Average high46°
Average low35°
Average precipitation0.08 in
Chance of precipitation35%
Record high67° (1964)
Record low15° (2019)
Thu, 1245° / 34°0.06Climate normal
45 °Climate normal

Grayslake, Thursday, 12 November

Climate normal for this date — 60-year average.

Average high45°
Average low34°
Average precipitation0.06 in
Chance of precipitation22%
Record high64° (1964)
Record low3° (2019)

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 Grayslake, 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 Grayslake, 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.