Observed 7:25 AM CDT at KCPS

Waterloo, IL weather

Foggy and 45°7°, 9°5° warmer than a typical Oct 23.

Forecasts agree

Now 45°7°

Fog

Wind: Calm; Up to 5 mph8 km/h through 8 PM
Visibility: 3 mi5 km; Fog · under 5 mi8 km
Dew point: 45°7°; Comfortable · up to 53°12° by 11 AM
Humidity: 100%; Air 45°7°, dew point 45°7° · fog or dew likely
UV index: 0Low; Moderate 11 AM–4 PM · peak 4
Air quality: 71Moderate; Main pollutant: PM2.5 (fine particles)
Pressure: 30.27 inHg1025 hPa; Rising slowly · +0.03 inHg+1.1 hPa in 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

Above 60°16° today by 10 AM
High 75°24° today at 4 PM
Below 60°16° tonight after 9 PM
Low 48°9° tomorrow at 6 AM

This morningUp to 66°19° by 11 AM · Clear
This afternoonUp to 75°24° by 4 PM · Clear
TonightDown to 49°9° by 5 AM · Partly cloudy
Tomorrow morningUp to 66°19° by 11 AM · Mostly cloudy
Tomorrow afternoonUp to 75°24° by 4 PM · Mostly cloudy
Tomorrow nightDown to 48°9° by 5 AM · Partly 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	Sunny	49°9° (likely 48°9° to 52°11°)	49°9°	0%	2 mph3 km/h from SE, gusts 7 mph11 km/h	93%	14%	0
Fri 9a	Sunny	54°12° (likely 53°12° to 58°14°)	54°12°	0%	2 mph3 km/h from SE, gusts 6 mph10 km/h	86%	3%	1
Fri 10a	Sunny	61°16° (likely 58°14° to 63°17°)	61°16°	0%	2 mph3 km/h from SE, gusts 10 mph16 km/h	72%	1%	2
Fri 11a	Sunny	66°19° (likely 62°17° to 68°20°)	66°19°	0%	3 mph5 km/h from SE, gusts 11 mph17 km/h	63%	0%	3
Fri 12p	Sunny	70°21° (likely 65°18° to 71°22°)	70°21°	0%	5 mph8 km/h from SE, gusts 10 mph17 km/h	53%	0%	4
Fri 1p	Sunny	72°22° (likely 68°20° to 73°23°)	72°22°	0%	5 mph8 km/h from SE, gusts 10 mph16 km/h	46%	0%	4
Fri 2p	Sunny	73°23° (likely 70°21° to 74°23°)	73°23°	0%	5 mph8 km/h from SE, gusts 10 mph16 km/h	44%	0%	4
Fri 3p	Sunny	74°23° (likely 72°22° to 75°24°)	74°23°	0%	3 mph5 km/h from SE, gusts 9 mph15 km/h	40%	0%	3
Fri 4p	Sunny	75°24° (likely 72°22° to 75°24°)	75°24°	0%	5 mph8 km/h from SE, gusts 9 mph14 km/h	38%	0%	2
Fri 5p	Sunny	73°23° (likely 70°21° to 73°23°)	73°23°	0%	3 mph5 km/h from SE, gusts 10 mph15 km/h	41%	0%	1
Fri 6p	Clear	70°21° (likely 66°19° to 70°21°)	70°21°	0%	3 mph5 km/h from SE, gusts 10 mph16 km/h	47%	0%	0
Fri 7p	Clear	65°18° (likely 62°17° to 65°18°)	65°18°	0%	3 mph5 km/h from SE, gusts 10 mph16 km/h	54%	0%	0
Fri 8p	Clear	60°16° (likely 60°16° to 62°17°)	60°16°	0%	3 mph5 km/h from SE, gusts 11 mph17 km/h	64%	5%	0
Fri 9p	Clear	58°14° (likely 57°14° to 61°16°)	58°14°	0%	3 mph5 km/h from SE, gusts 12 mph19 km/h	69%	12%	0
Fri 10p	Clear	56°13° (likely 55°13° to 59°15°)	56°13°	0%	3 mph5 km/h from SE, gusts 12 mph19 km/h	74%	17%	0
Fri 11p	Clear	55°13° (likely 55°13° to 58°14°)	55°13°	0%	3 mph5 km/h from SE, gusts 12 mph19 km/h	74%	24%	0
Sat 12a	Clear	54°12° (likely 54°12° to 57°14°)	54°12°	0%	3 mph5 km/h from SE, gusts 11 mph18 km/h	77%	27%	0
Sat 1a	Mostly clear	53°12° (likely 52°11° to 56°13°)	53°12°	0%	2 mph3 km/h from SE, gusts 10 mph16 km/h	80%	57%	0
Sat 2a	Mostly clear	51°11° (likely 51°11° to 54°12°)	51°11°	0%	2 mph3 km/h from SE, gusts 9 mph15 km/h	83%	53%	0
Sat 3a	Mostly clear	51°11° (likely 50°10° to 53°12°)	51°11°	0%	2 mph3 km/h from SE, gusts 8 mph12 km/h	83%	62%	0
Sat 4a	Mostly clear	50°10° (likely 49°9° to 52°11°)	50°10°	0%	2 mph3 km/h from SE, gusts 6 mph10 km/h	86%	57%	0
Sat 5a	Mostly clear	49°9° (likely 48°9° to 51°11°)	49°9°	0%	2 mph3 km/h from SE, gusts 6 mph10 km/h	89%	50%	0
Sat 6a	Mostly clear	48°9° (likely 47°8° to 50°10°)	48°9°	0%	2 mph3 km/h from SE, gusts 6 mph9 km/h	93%	57%	0
Sat 7a	Cloudy	48°9° (likely 46°8° to 50°10°)	48°9°	0%	2 mph3 km/h from SE, gusts 6 mph10 km/h	89%	80%	0
Sat 8a	Cloudy	49°9° (likely 46°8° to 52°11°)	49°9°	0%	2 mph3 km/h from E, gusts 5 mph9 km/h	89%	79%	0
Sat 9a	Mostly sunny	54°12° (likely 51°11° to 57°14°)	54°12°	0%	2 mph3 km/h from SE, gusts 5 mph9 km/h	86%	70%	1
Sat 10a	Mostly sunny	61°16° (likely 56°13° to 62°17°)	61°16°	0%	3 mph5 km/h from SE, gusts 9 mph14 km/h	72%	65%	2
Sat 11a	Cloudy	66°19° (likely 61°16° to 67°19°)	66°19°	0%	3 mph5 km/h from SE, gusts 9 mph14 km/h	61%	78%	3
Sat 12p	Cloudy	69°21° (likely 66°19° to 71°22°)	69°21°	0%	3 mph5 km/h from SE, gusts 8 mph12 km/h	53%	80%	4
Sat 1p	Cloudy	72°22° (likely 70°21° to 74°23°)	72°22°	0%	3 mph5 km/h from SE, gusts 7 mph11 km/h	44%	74%	4
Sat 2p	Partly sunny	73°23° (likely 72°22° to 75°24°)	73°23°	0%	3 mph5 km/h from SE, gusts 7 mph11 km/h	43%	76%	4
Sat 3p	Cloudy	74°23° (likely 73°23° to 76°24°)	74°23°	0%	3 mph5 km/h from SE, gusts 7 mph11 km/h	41%	66%	3
Sat 4p	Partly sunny	75°24° (likely 73°23° to 75°24°)	75°24°	0%	3 mph5 km/h from SE, gusts 8 mph12 km/h	38%	52%	2
Sat 5p	Mostly sunny	73°23° (likely 71°22° to 73°23°)	73°23°	0%	3 mph5 km/h from SE, gusts 8 mph13 km/h	44%	46%	1
Sat 6p	Clear	70°21° (likely 66°19° to 70°21°)	70°21°	0%	2 mph3 km/h from SE, gusts 7 mph12 km/h	49%	42%	0
Sat 7p	Clear	65°18° (likely 62°17° to 65°18°)	65°18°	0%	2 mph3 km/h from SE, gusts 7 mph12 km/h	56%	44%	0
Sat 8p	Clear	60°16° (likely 60°16° to 62°17°)	60°16°	0%	2 mph3 km/h from SE, gusts 8 mph12 km/h	64%	47%	0
Sat 9p	Mostly clear	57°14° (likely 57°14° to 60°16°)	57°14°	0%	2 mph3 km/h from SE, gusts 7 mph12 km/h	69%	65%	0
Sat 10p	Cloudy	56°13° (likely 56°13° to 58°14°)	56°13°	0%	2 mph3 km/h from SE, gusts 8 mph13 km/h	72%	70%	0
Sat 11p	Mostly clear	55°13° (likely 55°13° to 57°14°)	55°13°	0%	2 mph3 km/h from SE, gusts 8 mph13 km/h	74%	70%	0
Sun 12a	Mostly clear	54°12° (likely 54°12° to 57°14°)	54°12°	0%	2 mph3 km/h from SE, gusts 8 mph13 km/h	77%	66%	0
Sun 1a	Cloudy	53°12° (likely 52°11° to 56°13°)	53°12°	0%	2 mph3 km/h from SE, gusts 6 mph10 km/h	80%	69%	0
Sun 2a	Partly cloudy	52°11° (likely 51°11° to 58°14°)	52°11°	0%	2 mph3 km/h from SE, gusts 4 mph7 km/h	83%	59%	0
Sun 3a	Partly cloudy	51°11° (likely 50°10° to 57°14°)	51°11°	0%	1 mph2 km/h from SE, gusts 4 mph6 km/h	83%	63%	0
Sun 4a	Partly cloudy	50°10° (likely 49°9° to 56°13°)	50°10°	0%	1 mph2 km/h from SE, gusts 4 mph6 km/h	86%	57%	0
Sun 5a	Partly cloudy	48°9° (likely 48°9° to 56°13°)	48°9°	0%	1 mph2 km/h from SE, gusts 3 mph6 km/h	89%	47%	0
Sun 6a	Partly cloudy	47°8° (likely 47°8° to 55°13°)	47°8°	0%	1 mph2 km/h from S, gusts 3 mph5 km/h	93%	54%	0
Sun 7a	Partly sunny	48°9° (likely 47°8° to 54°12°)	48°9°	0%	1 mph2 km/h from S, gusts 3 mph5 km/h	89%	43%	0

Days ahead

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

Today, Oct 23. Sunny. High 75°24°, low 48°9°. Typical 66°19° / 44°7°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 49°9°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 75°24°
  Dry
3. Evening
  6 PM–midnight
  Clear, 60°16°
  Dry
4. Overnight
  midnight–6 AM
  Mostly clear, 49°9°
  Dry
Official NWS forecast
Today: Sunny, with a high near 75. Southeast wind around 5 mph.
Tonight: Mostly clear, with a low around 48. Southeast wind around 3 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
72°22°–75°24°
Low, likely
48°9°–50°10°
Typical high / low
66°19° / 44°7°
Wind
8 mph13 km/h, gusts 17 mph28 km/h
UV peak
5
Tomorrow, Oct 24. Mostly sunny. High 75°24°, low 47°8°. Typical 66°19° / 43°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Mostly sunny, 49°9°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 75°24°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 60°16°
  Dry
4. Overnight
  midnight–6 AM
  Partly cloudy, 48°9°
  Dry
Official NWS forecast
Day: Sunny, with a high near 75. Southeast wind around 3 mph.
Night: Mostly clear, with a low around 47. Southeast wind around 2 mph.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
74°23°–76°24°
Low, likely
46°8°–50°10°
Typical high / low
66°19° / 43°6°
Wind
8 mph12 km/h, gusts 16 mph26 km/h
UV peak
4
Sunday, Oct 25. Partly sunny. High 77°25°, low 50°10°. Typical 66°19° / 43°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Cloudy, 51°11°
  Dry
2. Afternoon
  noon–6 PM
  Partly sunny, 77°25°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 63°17°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 56°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 77. South wind around 1 mph.
Night: Mostly cloudy, with a low around 50.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
77°25°–79°26°
Low, likely
47°8°–53°12°
Typical high / low
66°19° / 43°6°
Wind
6 mph10 km/h
UV peak
4
Monday, Oct 26. Mostly cloudy. High 76°24°, low 50°10°. Typical 65°18° / 42°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Cloudy, 56°13°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 76°24°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 63°17°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 53°12°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 76.
Night: Mostly cloudy, with a low around 50.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
75°24°–77°25°
Low, likely
50°10°–57°14°
Typical high / low
65°18° / 42°6°
Wind
7 mph11 km/h, gusts 16 mph26 km/h
UV peak
4
Tuesday, Oct 27. Cloudy. High 74°23°, low 50°10°. Typical 65°18° / 42°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Cloudy, 54°12°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 73°23°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 62°17°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 54°12°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Partly sunny, with a high near 74.
Night: Mostly cloudy, with a low around 50.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
72°22°–74°23°
Low, likely
48°9°–56°13°
Typical high / low
65°18° / 42°6°
Wind
8 mph13 km/h, gusts 17 mph28 km/h
UV peak
4
Wednesday, Oct 28. Partly sunny. High 75°24°, low 51°11°. Typical 64°18° / 42°6°. Dry. Forecasts agree.
1. Morning
  6 AM–noon
  Sunny, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 77°25°
  Dry
3. Evening
  6 PM–midnight
  Clear, 64°18°
  Dry
4. Overnight
  midnight–6 AM
  Partly cloudy, 56°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 75.
Night: Mostly clear, with a low around 51.
Forecasts agreeIndependent forecasts are close; the range is narrow.
High, likely
75°24°–78°26°
Low, likely
48°9°–56°13°
Typical high / low
64°18° / 42°6°
Wind
10 mph16 km/h, gusts 24 mph39 km/h
UV peak
4
Thursday, Oct 29. Partly sunny. High 76°24°, low 50°10°. Typical 64°18° / 41°5°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Partly sunny, 57°14°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 74°23°
  Dry
3. Evening
  6 PM–midnight
  Clear, 63°17°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 55°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 76.
Night: Partly cloudy, with a low around 50.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
69°21°–79°26°
Low, likely
50°10°–58°14°
Typical high / low
64°18° / 41°5°
Wind
13 mph20 km/h, gusts 27 mph44 km/h
UV peak
3
Friday, Oct 30. Drizzle. High 70°21°, low 52°11°. Typical 63°17° / 41°5°. Rain 0.02 in0.5 mm, 10% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Cloudy, 55°13°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 68°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 57°14°
  Dry
4. Overnight
  midnight–6 AM
  Drizzle, 49°9°
  Dry
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
63°17°–74°23°
Low, likely
43°6°–57°14°
Typical high / low
63°17° / 41°5°
Wind
9 mph14 km/h, gusts 16 mph26 km/h
UV peak
2
Saturday, Oct 31. Cloudy. High 66°19°, low 51°11°. Typical 63°17° / 41°5°. Rain 0.16 in4.1 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Mostly sunny, 51°10°
  20% chance · 0.03 in0.7 mm
2. Afternoon
  noon–6 PM
  Cloudy, 65°18°
  30% chance
3. Evening
  6 PM–midnight
  Cloudy, 60°15°
  30% chance
4. Overnight
  midnight–6 AM
  Cloudy, 55°13°
  30% chance · 0.02 in0.4 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
59°15°–70°21°
Low, likely
45°7°–59°15°
Typical high / low
63°17° / 41°5°
Wind
11 mph18 km/h, gusts 23 mph36 km/h
UV peak
1
Sunday, Nov 1. Cloudy. High 69°21°, low 55°13°. Typical 62°17° / 40°4°. Rain 0.17 in4.3 mm, 30% chance. Mostly agree.
1. Morning
  6 AM–noon
  Cloudy, 56°13°
  30% chance · 0.01 in0.3 mm
2. Afternoon
  noon–6 PM
  Partly sunny, 69°21°
  30% chance
3. Evening
  6 PM–midnight
  Cloudy, 61°16°
  30% 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
67°19°–72°22°
Low, likely
51°11°–60°16°
Typical high / low
62°17° / 40°4°
Wind
11 mph18 km/h, gusts 24 mph39 km/h
UV peak
3

10 days15 days30 days

The outlook

Today
Dry, high 75°, low 48°.
Tomorrow
Dry, high 75°, low 47°.
Sunday
Dry, high 77°, low 50°.
Rest of week
Mostly dry, highs 66–76°.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (LSX) (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

Mississippi River at St. Louis

20 mi

Below flood stage

Level: 8.7 ft
Flow: 179,000 cfs

Forecast peak 8.5 ft Fri 1 PM

Reading from Fri 6:30 AM · NWS gauge page

Mississippi River at Herculaneum

13 mi

Below flood stage

Level: 6.2 ft

Reading from Fri 6 AM · NWS gauge page

Meramec River at Arnold

14 mi

Below flood stage

Level: 5.9 ft
Flow: 7,430 cfs

Reading from Fri 6:30 AM · NWS gauge page

Kaskaskia River at New Athens

14 mi

Below flood stage

Level: 68.6 ft
Flow: 583 cfs

Reading from Fri 6 AM · NWS gauge page

For your home

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

Heating this week

About 82% less heating than a typical week.

This week 14Typical 79

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F: 1
h below 17°F: 0
h below 5°F: 0

47, 17 and 5°F are the test points heat pumps are rated at.

Comfort

Dry air outside (dew point 45°F).

Open the windows?

Today, 10:00 AM–8:00 PM

Good stretch to open the windows.

Is this typical?

Cahokia St. Louis Downtown Airport · official normals 1991–2020 · records 1997–2026

Oct 23, today vs a typical year

Today’s expected high is 9°5° warmer than typical.

Last 7 days vs normal

On average 1° colder than normal (daily mean temperature).

−9°−5°SatOct 17
−6°−3°SunOct 18
−2°−1°MonOct 19
+3°+2°TueOct 20
+4°+2°WedOct 21
+5°+3°ThuOct 22
—FriOct 23

Waterloo weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 54 min; Losing 2 min 16 s a day; shortest Dec 21, 1 h 24 min less
Golden hour: 5:35–6:28 PM; Morning 7:01–7:54 AM
Blue hour: 6:28–6:38 PM; Morning 6:50–7:01 AM; first light 6:50 AM

Stars tonight? Fair

Mostly clear 6:38 PM–12 AM, but the moon is 95% lit and up.

Moon

Waxing gibbous

92% lit · growing

Today: sets 4:26 AM · rises 4:41 PM
Full moon: Oct 25
New moon: Nov 9

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

Waterloo, IL weather

Next 2 hours

Next 48 hours

Days ahead

The outlook

Today

Tomorrow

Sunday

Rest of week

What changed since yesterday

Radar

Rivers

Mississippi River at St. Louis

Mississippi River at Herculaneum

Meramec River at Arnold

Kaskaskia River at New Athens

For your home

Heating this week

Heat-pump hours, next 7 days

Comfort

Open the windows?

Is this typical?

Oct 23, today vs a typical year

Last 7 days vs normal

Sun & moon

Sun

Stars tonight? Fair

Moon