Waterloo, IL Weather Forecast & Current Conditions

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Waterloo, IL Weather Maps

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Waterloo Weather Map
UTC Time: 9/26/2026, 12:59
Your Time:
Aeronautical Observation: Automated synoptic observations via NWS Gateway.
Auto-refresh in: 5:02

Waterloo, IL Regional Weather

Expires:202609261400;;085713
ASUS43 KLOT 261256
RWRIL 

ILLINOIS REGIONAL WEATHER ROUNDUP
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
800 AM CDT SAT SEP 26 2026

NOTE: "FAIR" INDICATES FEW OR NO CLOUDS BELOW 12,000 FEET WITH NO
SIGNIFICANT WEATHER AND/OR OBSTRUCTIONS TO VISIBILITY.

* THESE STATIONS ARE NOT UNDER NWS QUALITY CONTROL. THEY ALSO MAY NOT
  REPORT WEATHER SUCH AS PRECIPITATION OR FOG.


ILZ079-100>102-261400-
SOUTHWEST ILLINOIS
  
CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
ALTON          CLOUDY    61  52  72 E3        30.18R TC  16           
$$


SKY/WX - Weather  TMP - Temperature  DP - Dew Point  RH - Humidity
WIND - Wind Direction/Speed PRES - Barometric Pressure VSB - Visibility
WCI - Wind Chill Index E13G22 Wind - East Wind 13 mph/Gusts of 22 mph

Waterloo, IL

Today
Sprinkles
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
75°/ 55° 24°/ 13°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
40%
Wed-Wed Night
Thunderstorms
78°26°
50%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
60%
Friday
Thunderstorms
78°26°
40%

Day: Mostly cloudy. A chance of sprinkles this morning. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable.

Alton, IL

Today
Sprinkles
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
78°/ 55° 26°/ 13°
0%
Monday
Sunny
78°/ 58° 26°/ 14°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
40%
Wednesday
Thunderstorms
78°/ 68° 26°/ 20°
60%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
60%

Day: Mostly cloudy. A chance of sprinkles this morning. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy in the evening, then becoming partly cloudy. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable.

Jefferson County, MO

Today
Sprinkles
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
75°/ 55° 24°/ 13°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
40%
Wed-Wed Night
Thunderstorms
78°26°
50%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
60%
Friday
Thunderstorms
78°26°
40%

Day: Mostly cloudy. A chance of sprinkles this morning. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable.

Alton, MO

Today
Sprinkles
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
78°/ 55° 26°/ 13°
0%
Monday
Sunny
78°/ 58° 26°/ 14°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
40%
Wednesday
Thunderstorms
78°/ 68° 26°/ 20°
60%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
60%

Day: Mostly cloudy. A chance of sprinkles this morning. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy in the evening, then becoming partly cloudy. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable.

Chester, IL

Today
Sprinkles
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 55° 24°/ 13°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
20%
Wed-Wed Night
Thunderstorms
78°26°
50%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
50%
Friday
Thunderstorms
78°26°
40%

Day: Partly sunny with a chance of sprinkles this morning, then mostly cloudy this afternoon. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy. Lows in the upper 50s. Northeast winds around 5 mph in the evening, becoming light and variable.

Chester, MO

Today
Sprinkles
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 55° 24°/ 13°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
20%
Wed-Wed Night
Thunderstorms
78°26°
50%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
50%
Friday
Thunderstorms
78°26°
40%

Day: Partly sunny with a chance of sprinkles this morning, then mostly cloudy this afternoon. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy. Lows in the upper 50s. Northeast winds around 5 mph in the evening, becoming light and variable.

Centralia, IL

Today
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
20%
Wed-Wed Night
Rain Showers
78°26°
50%
Thursday
Thunderstorms
78°26°
50%
Friday
Thunderstorms
78°26°
50%

Day: Partly sunny this morning, then becoming mostly cloudy. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy in the evening, then becoming partly cloudy. Lows in the upper 50s. Light and variable winds.

Farmington, MO

Today
Partly Cloudy
75°/ 58° 24°/ 14°
0%
Sunday
Sunny
78°/ 58° 26°/ 14°
0%
Monday
Sunny
78°/ 58° 26°/ 14°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
20%
Wednesday
Thunderstorms
78°26°
50%
Thursday
Thunderstorms
78°26°
50%
Friday
Thunderstorms
78°26°
50%

Day: Partly sunny. Highs in the mid 70s. East winds around 5 mph.

Night: Mostly cloudy. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable.

Washington, MO

Today
Sprinkles
72°/ 58° 22°/ 14°
20%
Sunday
Partly Cloudy
75°/ 58° 24°/ 14°
0%
Monday
Sunny
78°/ 58° 26°/ 14°
0%
Tuesday
Rain Showers
82°/ 65° 28°/ 18°
50%
Wed Night
Thunderstorms
65°18°
50%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
60%

Day: Mostly cloudy with a chance of sprinkles this morning, then partly sunny this afternoon. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy. A slight chance of showers after midnight. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable. Chance of rain 20 percent.

Pinckneyville, IL

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Mon-Mon Night
Clear
78°26°
0%
Tuesday
Sunny
82°/ 62° 28°/ 17°
0%
Wed-Wed Night
Rain Showers
80°27°
40%
Thursday
Rain Showers
78°/ 62° 26°/ 17°
50%
Friday
Rain Showers
78°26°
40%

Night: Mostly cloudy with a chance of sprinkles. Lows in the upper 50s. Northeast winds around 5 mph.

Perryville, MO

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
75°/ 55° 24°/ 13°
0%
Mon-Mon Night
Clear
78°26°
0%
Tuesday
Sunny
80°/ 65° 27°/ 18°
0%
Wednesday
Rain Showers
78°/ 65° 26°/ 18°
40%
Thursday
Thunderstorms
78°/ 62° 26°/ 17°
50%
Friday
Rain Showers
78°26°
40%

Night: Mostly cloudy with a chance of sprinkles. Near steady temperature in the upper 50s. Northeast winds around 5 mph.

Carbondale, IL

Overnight
Sprinkles
60°16°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Monday
Clear
78°26°
0%
Tuesday
Clear
78°/ 65° 26°/ 18°
0%
Wed-Wed Night
Rain Showers
80°27°
40%
Thursday
Rain Showers
78°/ 65° 26°/ 18°
50%
Friday
Rain Showers
78°26°
40%

Night: Mostly cloudy with a chance of sprinkles. Near steady temperature around 60. Northeast winds around 5 mph.

Greene County, IL

Today
Rain Showers
72°/ 58° 22°/ 14°
20%
Sunday
Sunny
75°/ 55° 24°/ 13°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
50%
Wednesday
Thunderstorms
78°/ 65° 26°/ 18°
70%
Thu Night
Rain Showers
62°17°
50%
Friday
Thunderstorms
78°26°
50%

Day: Mostly cloudy. A chance of sprinkles this morning, then a slight chance of showers this afternoon. Highs in the lower 70s. East winds around 5 mph. Chance of rain 20 percent.

Night: Mostly cloudy. A slight chance of showers after midnight. Lows in the upper 50s. East winds around 5 mph in the evening, becoming light and variable. Chance of rain 20 percent.

Litchfield, IL

Today
Partly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Monday
Sunny
78°/ 55° 26°/ 13°
0%
Tuesday
Sunny
82°/ 62° 28°/ 17°
20%
Wednesday
Thunderstorms
78°/ 62° 26°/ 17°
60%
Thursday
Thunderstorms
62°17°
50%
Friday
Thunderstorms
62°17°
50%

Day: Partly sunny. Highs in the lower 70s. East winds around 5 mph.

Night: Mostly cloudy. Lows in the upper 50s. Light and variable winds.

Cape Girardeau, MO

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
75°/ 55° 24°/ 13°
0%
Monday
Clear
78°26°
0%
Tuesday
Clear
78°/ 62° 26°/ 17°
0%
Wed-Wed Night
Rain Showers
80°27°
40%
Thursday
Rain Showers
78°/ 62° 26°/ 17°
50%
Friday
Rain Showers
78°26°
40%

Night: Partly cloudy with a chance of sprinkles. Near steady temperature in the upper 50s. Northeast winds around 5 mph.

Mount Vernon, IL

Overnight
Sprinkles
55°13°
0%
Saturday
Mostly Cloudy
72°/ 55° 22°/ 13°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Mon-Mon Night
Clear
78°26°
0%
Tuesday
Sunny
82°/ 62° 28°/ 17°
0%
Wed-Wed Night
Rain Showers
80°27°
40%
Thu-Thu Night
Rain Showers
80°27°
50%
Friday
Rain Showers
80°27°
50%

Night: Mostly cloudy with a chance of sprinkles. Lows in the mid 50s. Northeast winds around 5 mph.

Marble Hill, MO

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
75°/ 58° 24°/ 14°
0%
Sunday
Partly Cloudy
78°/ 55° 26°/ 13°
0%
Mon-Mon Night
Clear
78°26°
0%
Tuesday
Sunny
82°/ 62° 28°/ 17°
0%
Wednesday
Rain Showers
80°/ 65° 27°/ 18°
40%
Thursday
Rain Showers
78°/ 62° 26°/ 17°
50%
Friday
Rain Showers
78°26°
40%

Night: Mostly cloudy with a chance of sprinkles. Near steady temperature in the upper 50s. Northeast winds around 5 mph.

West Frankfort, IL

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Partly Cloudy
75°/ 52° 24°/ 11°
0%
Mon-Mon Night
Clear
78°26°
0%
Tuesday
Sunny
82°/ 65° 28°/ 18°
0%
Wed-Wed Night
Rain Showers
82°28°
40%
Thursday
Rain Showers
80°/ 65° 27°/ 18°
50%
Friday
Rain Showers
80°27°
40%

Night: Mostly cloudy with a chance of sprinkles. Lows in the upper 50s. Northeast winds around 5 mph.

Herrin, IL

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Monday
Clear
78°26°
0%
Tuesday
Clear
78°/ 65° 26°/ 18°
0%
Wednesday
Rain Showers
82°/ 68° 28°/ 20°
40%
Thursday
Rain Showers
80°/ 65° 27°/ 18°
50%
Friday
Rain Showers
80°27°
40%

Night: Mostly cloudy with a chance of sprinkles. Near steady temperature in the upper 50s. Northeast winds around 5 mph.

Jonesboro, IL

Overnight
Sprinkles
58°14°
0%
Saturday
Mostly Cloudy
72°/ 58° 22°/ 14°
0%
Sunday
Sunny
75°/ 52° 24°/ 11°
0%
Monday
Clear
78°26°
0%
Tuesday
Clear
78°/ 65° 26°/ 18°
0%
Wednesday
Rain Showers
82°/ 68° 28°/ 20°
40%
Thursday
Rain Showers
80°/ 65° 27°/ 18°
50%
Friday
Rain Showers
80°27°
40%

Night: Mostly cloudy with a chance of sprinkles. Near steady temperature in the upper 50s. Northeast winds around 5 mph.

Names listed above may include county names.

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