Dense Fog Advisory
Ends in 14 min
When
Until 9 AM CDT this morning.
Where
McHenry County.
Issued for this forecast zone · National Weather Service Chicago IL
What, impacts and precautionsHide details
What
Visibility less than one mile in dense fog.
Impacts
Low visibility could make driving conditions hazardous.
Precautionary actions
If driving, slow down, use your headlights, and leave plenty of distance ahead of you.
Areas: McHenry
See it on weather.gov (opens in a new tab)

Observed 7:35 AM CDT at KUGN

Wonder Lake, IL weather

Foggy and 45°7°, 13°7° warmer than a typical Oct 23.

Forecasts agree

Now 45°7°

Fog

Wind: Calm; Up to 5 mph8 km/h through 8 PM
Visibility: 0.5 mi0.8 km; Fog · under 1 mi1.6 km
Dew point: 45°7°; Comfortable
Humidity: 100%; Air 45°7°, dew point 45°7° · fog or dew likely
UV index: 0Low; Moderate 12–3 PM · peak 3
Air quality (notable): 114Unhealthy for sensitive groups; PM2.5 (fine particles) · tomorrow moderate
Pressure: 30.32 inHg1027 hPa; Rising slowly · +0.02 inHg+0.8 hPa in 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

Fog until 10 AM
Above 60°16° today by 10 AM
High 72°22° today at 2 PM
Below 60°16° tonight after 8 PM

This morningUp to 65°18° by 11 AM · Partly cloudy
This afternoonUp to 72°22° by 2 PM · Clear
TonightDown to 49°9° by 5 AM · Partly cloudy
Tomorrow morningUp to 63°17° by 11 AM · Mostly cloudy
Tomorrow afternoonUp to 70°21° by 2 PM · Mostly cloudy
Tomorrow nightDown to 52°11° by 5 AM · Mostly cloudy

Hourly forecast, next 48 hours, in the place's local time
Hour	Conditions	Temperature	Feels like	Precipitation	Wind	Humidity	Cloud cover	UV index
Fri 8a	Fog	50°10° (likely 46°8° to 50°10°)	50°10°	0%	0 mph0 km/h, gusts 4 mph6 km/h	89%	61%	0
Fri 9a	Fog	55°13° (likely 49°9° to 55°13°)	55°13°	0%	0 mph0 km/h, gusts 6 mph10 km/h	79%	58%	0
Fri 10a	Partly sunny	60°16° (likely 52°11° to 60°16°)	60°16°	0%	5 mph8 km/h from SSE, gusts 8 mph13 km/h	71%	22%	1
Fri 11a	Sunny	65°18° (likely 59°15° to 65°18°)	65°18°	0%	5 mph8 km/h from S, gusts 11 mph18 km/h	62%	2%	2
Fri 12p	Sunny	68°20° (likely 63°17° to 68°20°)	68°20°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	54%	0%	3
Fri 1p	Sunny	70°21° (likely 66°19° to 70°21°)	70°21°	0%	5 mph8 km/h from S, gusts 10 mph17 km/h	49%	0%	3
Fri 2p	Sunny	72°22° (likely 68°20° to 72°22°)	72°22°	0%	5 mph8 km/h from SSE, gusts 10 mph16 km/h	46%	1%	3
Fri 3p	Sunny	72°22° (likely 69°21° to 72°22°)	72°22°	0%	5 mph8 km/h from SSE, gusts 10 mph15 km/h	46%	3%	2
Fri 4p	Sunny	71°22° (likely 68°20° to 71°22°)	71°22°	0%	5 mph8 km/h from SSE, gusts 9 mph14 km/h	46%	5%	1
Fri 5p	Sunny	68°20° (likely 65°18° to 68°20°)	69°21°	0%	5 mph8 km/h from SE, gusts 11 mph18 km/h	52%	10%	0
Fri 6p	Mostly clear	64°18° (likely 60°16° to 64°18°)	64°18°	0%	5 mph8 km/h from ESE, gusts 10 mph16 km/h	60%	51%	0
Fri 7p	Mostly clear	60°16° (likely 57°14° to 60°16°)	60°16°	0%	5 mph8 km/h from ESE, gusts 10 mph17 km/h	70%	50%	0
Fri 8p	Mostly clear	58°14° (likely 55°13° to 58°14°)	58°14°	0%	5 mph8 km/h from SE, gusts 10 mph16 km/h	77%	49%	0
Fri 9p	Mostly clear	56°13° (likely 53°12° to 56°13°)	56°13°	0%	5 mph8 km/h from SE, gusts 10 mph16 km/h	80%	62%	0
Fri 10p	Clear	54°12° (likely 52°11° to 55°13°)	54°12°	0%	5 mph8 km/h from SE, gusts 10 mph16 km/h	82%	21%	0
Fri 11p	Partly cloudy	54°12° (likely 52°11° to 54°12°)	54°12°	0%	5 mph8 km/h from SE, gusts 10 mph16 km/h	83%	34%	0
Sat 12a	Partly cloudy	53°12° (likely 52°11° to 54°12°)	53°12°	0%	5 mph8 km/h from SSE, gusts 11 mph17 km/h	84%	33%	0
Sat 1a	Partly cloudy	52°11° (likely 50°10° to 53°12°)	52°11°	0%	5 mph8 km/h from SSE, gusts 12 mph19 km/h	84%	67%	0
Sat 2a	Cloudy	52°11° (likely 49°9° to 53°12°)	52°11°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	81%	77%	0
Sat 3a	Partly cloudy	51°11° (likely 48°9° to 52°11°)	50°10°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	83%	67%	0
Sat 4a	Cloudy	50°10° (likely 48°9° to 52°11°)	48°9°	0%	5 mph8 km/h from SSE, gusts 11 mph17 km/h	83%	85%	0
Sat 5a	Cloudy	49°9° (likely 48°9° to 52°11°)	48°9°	0%	5 mph8 km/h from SSE, gusts 11 mph17 km/h	84%	92%	0
Sat 6a	Cloudy	49°9° (likely 47°8° to 51°11°)	47°8°	0%	5 mph8 km/h from SSE, gusts 11 mph17 km/h	86%	90%	0
Sat 7a	Cloudy	48°9° (likely 48°9° to 51°11°)	46°8°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	87%	80%	0
Sat 8a	Cloudy	50°10° (likely 48°9° to 52°11°)	48°9°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	85%	79%	0
Sat 9a	Cloudy	54°12° (likely 51°11° to 55°13°)	54°12°	0%	5 mph8 km/h from S, gusts 13 mph20 km/h	81%	71%	1
Sat 10a	Cloudy	59°15° (likely 57°14° to 60°16°)	59°15°	0%	5 mph8 km/h from S, gusts 15 mph24 km/h	75%	72%	2
Sat 11a	Cloudy	63°17° (likely 60°16° to 64°18°)	63°17°	0%	10 mph16 km/h from S, gusts 16 mph26 km/h	67%	69%	2
Sat 12p	Cloudy	66°19° (likely 63°17° to 66°19°)	67°19°	0%	10 mph16 km/h from S, gusts 16 mph26 km/h	60%	85%	3
Sat 1p	Cloudy	69°21° (likely 64°18° to 69°21°)	69°21°	0%	10 mph16 km/h from S, gusts 16 mph25 km/h	55%	78%	3
Sat 2p	Cloudy	70°21° (likely 66°19° to 70°21°)	70°21°	0%	10 mph16 km/h from S, gusts 16 mph25 km/h	52%	78%	3
Sat 3p	Cloudy	70°21° (likely 66°19° to 70°21°)	70°21°	0%	10 mph16 km/h from S, gusts 16 mph25 km/h	51%	71%	2
Sat 4p	Mostly cloudy	70°21° (likely 65°18° to 70°21°)	70°21°	0%	10 mph16 km/h from S, gusts 16 mph25 km/h	51%	66%	2
Sat 5p	Mostly cloudy	68°20° (likely 63°17° to 68°20°)	68°20°	0%	10 mph16 km/h from S, gusts 16 mph26 km/h	55%	65%	1
Sat 6p	Cloudy	65°18° (likely 60°16° to 65°18°)	65°18°	0%	5 mph8 km/h from S, gusts 11 mph17 km/h	61%	75%	0
Sat 7p	Cloudy	62°17° (likely 58°14° to 62°17°)	62°17°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	65%	73%	0
Sat 8p	Partly cloudy	60°16° (likely 56°13° to 60°16°)	60°16°	0%	5 mph8 km/h from SSE, gusts 11 mph18 km/h	67%	70%	0
Sat 9p	Partly cloudy	58°14° (likely 55°13° to 58°14°)	59°15°	0%	5 mph8 km/h from S, gusts 11 mph18 km/h	69%	69%	0
Sat 10p	Cloudy	57°14° (likely 54°12° to 57°14°)	57°14°	0%	5 mph8 km/h from S, gusts 12 mph20 km/h	71%	57%	0
Sat 11p	Cloudy	56°13° (likely 54°12° to 56°13°)	56°13°	0%	5 mph8 km/h from S, gusts 12 mph20 km/h	72%	64%	0
Sun 12a	Partly cloudy	56°13° (likely 53°12° to 56°13°)	56°13°	0%	5 mph8 km/h from S, gusts 12 mph20 km/h	72%	68%	0
Sun 1a	Partly cloudy	55°13° (likely 53°12° to 55°13°)	55°13°	0%	5 mph8 km/h from S, gusts 13 mph21 km/h	73%	73%	0
Sun 2a	Partly cloudy	55°13° (likely 52°11° to 55°13°)	55°13°	0%	5 mph8 km/h from S, gusts 12 mph19 km/h	72%	70%	0
Sun 3a	Cloudy	54°12° (likely 52°11° to 54°12°)	54°12°	0%	5 mph8 km/h from S, gusts 12 mph19 km/h	73%	72%	0
Sun 4a	Cloudy	53°12° (likely 52°11° to 54°12°)	53°12°	0%	5 mph8 km/h from S, gusts 12 mph20 km/h	74%	79%	0
Sun 5a	Cloudy	52°11° (likely 52°11° to 54°12°)	52°11°	0%	5 mph8 km/h from SSW, gusts 12 mph19 km/h	75%	81%	0
Sun 6a	Cloudy	51°11° (likely 51°11° to 54°12°)	51°11°	0%	5 mph8 km/h from SSW, gusts 11 mph18 km/h	77%	84%	0
Sun 7a	Mostly cloudy	51°11° (likely 51°11° to 54°12°)	51°11°	0%	5 mph8 km/h from SSW, gusts 11 mph18 km/h	77%	75%	0

Days ahead

Shaded: typical range for these dates (1991–2020)

Today, Oct 23. Fog. High 72°22°, low 48°9°. Typical 59°15° / 40°4°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Partly sunny, 50°10°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 72°22°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 58°14°
  Dry
4. Overnight
  midnight–6 AM
  Partly cloudy, 49°9°
  Dry
Official NWS forecast
Today: Patchy fog before 9am. Sunny. High near 72, with temperatures falling to around 68 in the afternoon. South southeast wind 0 to 5 mph.
Tonight: Partly cloudy, with a low around 48. Southeast wind around 5 mph, with gusts as high as 10 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
69°21°–72°22°
Low, likely
44°7°–48°9°
Typical high / low
59°15° / 40°4°
Wind
7 mph12 km/h, gusts 14 mph23 km/h
UV peak
4
Tomorrow, Oct 24. Cloudy. High 70°21°, low 51°11°. Typical 59°15° / 39°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 50°10°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 70°21°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 60°16°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 52°11°
  Dry
Official NWS forecast
Day: Partly sunny. High near 70, with temperatures falling to around 68 in the afternoon. South wind 5 to 10 mph, with gusts as high as 20 mph.
Night: Mostly cloudy, with a low around 51. South wind around 5 mph, with gusts as high as 15 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
66°19°–70°21°
Low, likely
47°8°–51°11°
Typical high / low
59°15° / 39°4°
Wind
10 mph15 km/h, gusts 19 mph31 km/h
UV peak
3
Sunday, Oct 25. Cloudy. High 73°23°, low 50°10°. Typical 58°14° / 39°4°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 53°12°
  Dry
2. Afternoon
  noon–6 PM
  Partly sunny, 71°22°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 59°15°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 50°10°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 73. South southwest wind around 5 mph.
Night: Mostly cloudy, with a low around 50.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
69°21°–74°23°
Low, likely
50°10°–54°12°
Typical high / low
58°14° / 39°4°
Wind
10 mph16 km/h, gusts 20 mph32 km/h
UV peak
3
Monday, Oct 26. Mostly cloudy. High 65°18°, low 47°8°. Typical 58°14° / 39°4°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 51°10°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 53°12°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 51°11°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly cloudy, with a high near 65.
Night: Mostly cloudy, with a low around 47.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
59°15°–68°20°
Low, likely
47°8°–50°10°
Typical high / low
58°14° / 39°4°
Wind
13 mph21 km/h, gusts 27 mph44 km/h
UV peak
3
Tuesday, Oct 27. Mostly cloudy. High 62°17°, low 48°9°. Typical 58°14° / 38°3°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 52°11°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 62°17°
  Dry
3. Evening
  6 PM–midnight
  Partly cloudy, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 54°12°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly cloudy, with a high near 62.
Night: Mostly cloudy, with a low around 48.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
58°14°–66°19°
Low, likely
48°9°–52°11°
Typical high / low
58°14° / 38°3°
Wind
11 mph17 km/h, gusts 28 mph45 km/h
UV peak
2
Wednesday, Oct 28. Cloudy. High 68°20°, low 48°9°. Typical 57°14° / 38°3°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 67°20°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 60°16°
  Dry
4. Overnight
  midnight–6 AM
  Mostly clear, 57°14°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 68.
Night: A slight chance of rain showers after 1am. Partly cloudy, with a low around 48.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
65°18°–71°22°
Low, likely
48°9°–54°12°
Typical high / low
57°14° / 38°3°
Wind
15 mph24 km/h, gusts 25 mph41 km/h
UV peak
3
Thursday, Oct 29. Showers. High 66°19°, low 45°7°. Typical 56°13° / 38°3°. Rain 0.03 in0.8 mm, 20% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Drizzle, 57°14°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 61°16°
  Dry
3. Evening
  6 PM–midnight
  Clear, 50°10°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 39°4°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: A slight chance of rain showers. Mostly sunny, with a high near 66.
Night: A slight chance of rain showers. Mostly cloudy, with a low around 45.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
61°16°–68°20°
Low, likely
45°7°–50°10°
Typical high / low
56°13° / 38°3°
Wind
17 mph27 km/h, gusts 43 mph69 km/h
Friday, Oct 30. Drizzle. High 57°14°, low 41°5°. Typical 56°13° / 37°3°. Rain 0.02 in0.5 mm, 20% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 40°5°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 54°12°
  Dry
3. Evening
  6 PM–midnight
  Clear, 45°7°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 40°4°
  20% chance · 0.02 in0.5 mm
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
51°11°–65°18°
Low, likely
38°3°–50°10°
Typical high / low
56°13° / 37°3°
Wind
12 mph19 km/h, gusts 30 mph48 km/h
UV peak
2
Saturday, Oct 31. Drizzle. High 58°14°, low 43°6°. Typical 55°13° / 37°3°. Rain 0.11 in2.8 mm, 40% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Drizzle, 42°6°
  20% chance · 0.02 in0.5 mm
2. Afternoon
  noon–6 PM
  Drizzle, 56°13°
  30% chance
3. Evening
  6 PM–midnight
  Cloudy, 51°10°
  40% chance
4. Overnight
  midnight–6 AM
  Cloudy, 52°11°
  40% chance
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
53°12°–64°18°
Low, likely
34°1°–54°12°
Typical high / low
55°13° / 37°3°
Wind
12 mph19 km/h, gusts 22 mph35 km/h
Sunday, Nov 1. Cloudy. High 63°17°, low 51°11°. Typical 55°13° / 37°3°. Rain 0.09 in2.3 mm, 40% chance. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 53°12°
  30% chance
2. Afternoon
  noon–6 PM
  Cloudy, 62°16°
  30% chance
3. Evening
  6 PM–midnight
  Partly cloudy, 54°12°
  20% chance
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
61°16°–66°19°
Low, likely
49°9°–53°12°
Typical high / low
55°13° / 37°3°
Wind
13 mph22 km/h, gusts 27 mph44 km/h
UV peak
2

10 days15 days30 days

The outlook

Today
Dry, high 72°, low 48°.
Tomorrow
Dry, high 70°, low 51°.
Sunday
Dry, high 73°, low 50°, warming up.
Rest of week
Mostly dry, highs 57–68°.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (LOT) (opens in a new tab)

What changed since yesterday

No meaningful changes from yesterday’s forecast.

Radar

Radar data: NOAA MRMS, rendered by forecast.blue

Radar loads when scrolled into view

Full-screen radar

Rivers

NOAA river gauges within 25 mi

Nippersink Creek at Wonder Lake

1.0 mi

Below flood stage

Level: 5.0 ft
Flow: 40 cfs

Reading from Fri 7:45 AM · NWS gauge page

Boone Creek near Mchenry

4.7 mi

Below flood stage

Level: 1.1 ft
Flow: 12 cfs

Reading from Fri 7:45 AM · NWS gauge page

Fox River near Johnsburg

5.8 mi

Below flood stage

Level: 4.1 ft

Reading from Fri 7:45 AM · NWS gauge page

Nippersink Creek near Spring Grove

6.7 mi

Below flood stage

Level: 4.5 ft
Flow: 135 cfs

Reading from Fri 8 AM · NWS gauge page

For your home

What this week’s weather means for heating, cooling, pipes and fresh air.

Heating this week

About 88% less heating than a typical week.

This week 14Typical 117

Heating degree days, base 65°F

Comfort

Dry air outside (dew point 45°F).

Open the windows?

Today, 10:00 AM–7:00 PM

Good stretch to open the windows.

Is this typical?

Lake Geneva Wwtp · official normals 1991–2020 · records 1945–2026

Oct 23, today vs a typical year

Today’s expected high is 13°7° warmer than typical.

Last 7 days vs normal

On average 4°2° colder than normal (daily mean temperature).

−9°−5°SatOct 17
−8°−4°SunOct 18
±0°MonOct 19
+2°+1°TueOct 20
—WedOct 21
—ThuOct 22
—FriOct 23

Wonder Lake weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 43 min; Losing 2 min 39 s a day; shortest Dec 21, 1 h 39 min less
Golden hour: 5:19–6:16 PM; Morning 6:58–7:54 AM
Blue hour: 6:16–6:27 PM; Morning 6:47–6:58 AM; first light 6:47 AM

Stars tonight? Poor

Clouds most of the night (about 60% cover).

Moon

Waxing gibbous

92% lit · growing

Today: sets 4:19 AM · rises 4:33 PM
Full moon: Oct 25
New moon: Nov 9

Looking west from Wonder Lake. A level horizon.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.

1 active weather alert

Dense Fog Advisory

Wonder Lake, IL weather

Next 2 hours

Next 48 hours

Days ahead

The outlook

Today

Tomorrow

Sunday

Rest of week

What changed since yesterday

Radar

Rivers

Nippersink Creek at Wonder Lake

Boone Creek near Mchenry

Fox River near Johnsburg

Nippersink Creek near Spring Grove

For your home

Heating this week

Comfort

Open the windows?

Is this typical?

Oct 23, today vs a typical year

Last 7 days vs normal

Sun & moon

Sun

Stars tonight? Poor

Moon