As of 07:01 CDT

Weather in Grayslake, IL

46°Current weather

Grayslake, Wednesday, 21 October, 07:01

Clear. Feels like 44°. High 71°, low 43°.

Pressure30.27 inHg
Wind3.8 mph SW
Humidity96%
Visibility6.2 mi
Dew point44°

Monthly outlook for Grayslake, IL: average high 59.9°, average low 47.5°. That is 3° above the climate normal for October. Precipitation is expected on 7 days (about 1.7 inches), against a normal of 5 days and 1.6 inches. The warmest day looks like 22 October (71.4°), the coolest 30 October (34.6°).

59.9°/47.5°
Average high / low
+3°
Above normal
7 / 5
Wet days / normal
1.7 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
21 October – 30 October61.6°55.7°+3.3°
31 October – 9 November57°51.4°+3.1°
10 November – 19 Novemberat normal46°—

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, 2271° / 44°0Clear
71 °Clear

Grayslake, Thursday, 22 October

Clear. High 71°, low 44°.

Pressure30.27 inHg
Wind2.4 mph E
Humidity63%
Visibility6.2 mi
Dew point54°
Fri, 2367° / 54°0Partly cloudy
67 °Partly cloudy

Grayslake, Friday, 23 October

Partly cloudy. High 67°, low 54°.

Pressure30.33 inHg
Wind2.5 mph SE
Humidity80%
Visibility6.2 mi
Dew point56°
Sat, 2466° / 51°0Overcast
66 °Overcast

Grayslake, Saturday, 24 October

Overcast. High 66°, low 51°.

Pressure30.39 inHg
Wind7.6 mph S
Humidity65%
Visibility6.2 mi
Dew point51°
Sun, 2569° / 52°0Overcast
69 °Overcast

Grayslake, Sunday, 25 October

Overcast. High 69°, low 52°.

Pressure30.33 inHg
Wind7.3 mph S
Humidity58%
Visibility—
Dew point50°
Mon, 2665° / 51°0Overcast
65 °Overcast

Grayslake, Monday, 26 October

Overcast. High 65°, low 51°.

Pressure30.24 inHg
Wind10.4 mph NE
Humidity73%
Visibility—
Dew point54°
Tue, 2751° / 49°0.17Light rain
51 °Light rain

Grayslake, Tuesday, 27 October

Light rain. High 51°, low 49°.

Pressure30.24 inHg
Wind9.6 mph N
Humidity91%
Visibility—
Dew point47°
Wed, 2858° / 48°0.15Rain
58 °Rain

Grayslake, Wednesday, 28 October

Rain. High 58°, low 48°.

Pressure30.12 inHg
Wind9.8 mph S
Humidity75%
Visibility—
Dew point48°
Thu, 2951° / 38°0.15Rain
51 °Rain

Grayslake, Thursday, 29 October

Rain. High 51°, low 38°.

Pressure30.15 inHg
Wind19.7 mph W
Humidity67%
Visibility—
Dew point32°
Fri, 3049° / 35°0Clear
49 °Clear

Grayslake, Friday, 30 October

Clear. High 49°, low 35°.

Pressure30.30 inHg
Wind8.5 mph NW
Humidity45%
Visibility—
Dew point26°
Sat, 3149° / 37°0Overcast
49 °Overcast

Grayslake, Saturday, 31 October

Overcast. High 49°, low 37°.

Pressure30.30 inHg
Wind10.2 mph SE
Humidity35%
Visibility—
Dew point21°
Sun, 0150° / 44°0.42Rain
50 °Rain

Grayslake, Sunday, 1 November

Rain. High 50°, low 44°.

Pressure30.00 inHg
Wind8.8 mph S
Humidity96%
Visibility—
Dew point48°
Mon, 0253° / 50°0.09Light rain
53 °Light rain

Grayslake, Monday, 2 November

Light rain. High 53°, low 50°.

Pressure29.97 inHg
Wind5.5 mph N
Humidity96%
Visibility—
Dew point52°
Tue, 0357° / 51°0Overcast
57 °Overcast

Grayslake, Tuesday, 3 November

Overcast. High 57°, low 51°.

Pressure30.00 inHg
Wind7.7 mph E
Humidity82%
Visibility—
Dew point51°
Wed, 0464° / 52°0.57Rain
64 °Rain

Grayslake, Wednesday, 4 November

Rain. High 64°, low 52°.

Pressure29.83 inHg
Wind17.8 mph S
Humidity81%
Visibility—
Dew point54°
Thu, 0569° / 60°0.15Rain
69 °Rain

Grayslake, Thursday, 5 November

Rain. High 69°, low 60°.

Pressure29.83 inHg
Wind17.7 mph S
Humidity69%
Visibility—
Dew point57°
From day 17 onward the outlook is built from 60-year climate statistics
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)
Fri, 1345° / 33°0.05Climate normal
45 °Climate normal

Grayslake, Friday, 13 November

Climate normal for this date — 60-year average.

Average high45°
Average low33°
Average precipitation0.05 in
Chance of precipitation25%
Record high67° (1999)
Record low2° (2019)
Sat, 1446° / 34°0.07Climate normal
46 °Climate normal

Grayslake, Saturday, 14 November

Climate normal for this date — 60-year average.

Average high46°
Average low34°
Average precipitation0.07 in
Chance of precipitation28%
Record high66° (1971)
Record low15° (1986)
Sun, 1546° / 35°0.08Climate normal
46 °Climate normal

Grayslake, Sunday, 15 November

Climate normal for this date — 60-year average.

Average high46°
Average low35°
Average precipitation0.08 in
Chance of precipitation28%
Record high68° (2025)
Record low17° (2019)
Mon, 1646° / 34°0.05Climate normal
46 °Climate normal

Grayslake, Monday, 16 November

Climate normal for this date — 60-year average.

Average high46°
Average low34°
Average precipitation0.05 in
Chance of precipitation17%
Record high62° (1988)
Record low21° (1997)
Tue, 1746° / 35°0.1Climate normal
46 °Climate normal

Grayslake, Tuesday, 17 November

Climate normal for this date — 60-year average.

Average high46°
Average low35°
Average precipitation0.1 in
Chance of precipitation28%
Record high68° (2016)
Record low15° (2014)
Wed, 1846° / 35°0.1Climate normal
46 °Climate normal

Grayslake, Wednesday, 18 November

Climate normal for this date — 60-year average.

Average high46°
Average low35°
Average precipitation0.1 in
Chance of precipitation28%
Record high64° (1975)
Record low12° (2014)
Thu, 1946° / 35°0.07Climate normal
46 °Climate normal

Grayslake, Thursday, 19 November

Climate normal for this date — 60-year average.

Average high46°
Average low35°
Average precipitation0.07 in
Chance of precipitation32%
Record high63° (1983)
Record low15° (2018)

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.