Local weather forecast

Weather in Lake Saint Louis, MO

Updated 2026-08-11 10:30 local time · ZIP codes 63367

Sunny
Now87°F

Sunny

High / Low102° / 77°
Rain chance3%
Wind14 mph
Weather alerts

Active alerts

1
Heat Advisory issued August 11 at 2:17AM CDT until August 12 at 8:00PM CDT by NWS St Louis MO

* WHAT...Heat index values up to 106. * WHERE...Portions of south central, southwest, and west central Illinois and central, east central, northeast, and southeast Missouri. * WHEN...Until 8 PM CDT Wednesday. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses.

Safety instructions

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1.

Hourly

Next hours

NowSunny87°3% rain
11 AMSunny96°2% rain
12 PMSunny99°1% rain
1 PMSunny101°1% rain
2 PMSunny101°1% rain
3 PMSunny102°1% rain
4 PMSunny102°1% rain
5 PMSunny101°1% rain
6 PMSunny98°1% rain
7 PMSunny94°1% rain
8 PMSunny89°2% rain
9 PMClear86°3% rain
Forecast

3-day weather forecast

Today2026-08-11
Sunny
102° 77°Sunny
Rain 3%Gust 14 mph
Tomorrow2026-08-12
Sunny
97° 78°Sunny
Rain 17%Gust 10 mph
Thursday2026-08-13
Sunny
104° 73°Sunny
Rain 36%Gust 12 mph
Conditions

Weather details

Feels like94°F
Humidity61%
Pressure29.95 inHg
Visibility6 mi
Wind14 mph SW
Wind gusts16 mph
Precipitation0.00 in
UV index4
Daylight

Sunrise, sunset and moon

Sunrise06:13 AM
Sunset08:03 PM
Moonrise04:16 AM
Moon phaseNew Moon
Practical guide

Weather insights for today

Umbrella not essential

Rain chance stays relatively low over the next 12 hours (up to 3%).

Choose light, breathable clothing

It feels like 94°F with winds near 14 mph.

Best window: 8 PM

89°F, 2% rain chance and 7 mph wind.

Allow a little extra driving time

Visibility is around 6 mi; gusts may reach 16 mph.

Running conditions are less comfortable

Current temperature is 87°F, wind 14 mph, rain chance up to 3%.

Moderate UV protection recommended

UV index is 4. Sunscreen and sunglasses are sensible for longer outdoor time.

Lake Saint Louis weather today

Sunny and 87°F in Lake Saint Louis, MO. Today's high is 102°F with a 3% rain chance. Winds are around 14 mph with gusts near 16 mph. Relative humidity is 61%, pressure is 29.95 inHg, and visibility is about 6 miles.

Tonight and tomorrow in Lake Saint Louis

Sunrise is at 06:13 AM and sunset is at 08:03 PM. Tomorrow's forecast calls for Sunny with a high near 97°F and a low near 78°F. The maximum rain chance is 17%.

Nearby

Weather near Lake Saint Louis

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