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Shaded-relief map of Lake St. Louis, Missouri: rivers, roads, the city limits and where the water drains.
MISSOURI · ST. CHARLES COUNTY

Lake St. Louis

19,160 people, 610 ft above sea level in St. Charles County.

610 ftElevation, city center
19,160People, 2024 estimate
9 sq miLand area
Sunny 47°
Sunny now Dew point 25° · WNW 3 mph · high 43°
City of Lake St. Louis River Interstate 2 miles
Explore the plate Order a print

The Lake St. Louis plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.

MILE1
TODAY

Today in Lake St. Louis

NWS forecast and National Blend of Models · updated 4:00 PM CST
RIGHT NOW St. Louis Lambert International Airport (KSTL) · 3:51 PM
Sunny
47° Sunny Feels like 46° · high of 43° near 4 PM
WindWNW 3 mphno gusts
Humidity42%rising to 89% by morning
Pressure30.30 in →steady
Visibility10 mihaze-free
CloudsClear
UV index—no forecast
Dew point 25° · Dry38° by Tuesday: more humid
DryComfortableStickyMuggyOppressive
NEXT RAIN
Clear
Not this weeknone in the forecast for a week
LIKELY AMOUNT—nothing expected
LAST RAINNov. 40.03 in · 10 dry days
ALERTS & OUTLOOKS
No watches or warnings for St. Charles County
NWS St Louis and the Storm Prediction Center · checked 4:46 PM
SUN & MOON
↑ 6:44 AM4:50 PM ↓
10 h 6 m of daylight, 2 minutes less than yesterday
Waxing crescent, 26% lit. Next full moon: Nov. 24.
AIR & POLLEN
33
GOODAir quality index · ozone
No pollen source yet.

The next three days, hour by hour

Sky: clear, cloudy, night Rain likely National Blend of Models
SATURDAY, NOV. 14
SUNDAY, NOV. 15
MONDAY, NOV. 16
TUESDAY, NOV. 17
4p
7p
10p
1a
4a
7a
10a
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4p
7p
10p
1a
4a
7a
10a
1p
4p
7p
10p
1a
4a
7a
10a
1p
clear night
clear night
clear night
clear night
mostly clear night
partly cloudy day
partly cloudy day
partly cloudy day
partly cloudy night
mostly clear night
mostly clear night
mostly clear night
mostly clear night
clear day
clear day
clear day
clear night
mostly clear night
clear night
clear night
clear night
clear day
clear day
clear day
TEMPERATURE °F
43°
32°
50°
34°
53°
36°
CHANCE OF RAIN
50%
WIND, MPH
0
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HOW IT FEELS · DEW POINT
Dry: dew points 28 to 38°

The next seven days, and how sure we are

Forecast, with the range 8 in 10 ensemble members agree on Normal, about 56° / 38°
SAT Nov. 14 Sunny Sunny
43° 30°
0% rain — NW 0 A
SUN Nov. 15 Partly cloudy; warmer Partly cloudy; warmer
54° 32°
0% rain — NE 0 A
MON Nov. 16 Sunny Sunny
57° 35°
0% rain — SE 0 A
TUE Nov. 17 Sunny Sunny
59° 38°
0% rain — SE 8 A
WED Nov. 18 Mostly sunny Mostly sunny
63° 47°
10% rain — SSE 14 B
THU Nov. 19 Partly cloudy Partly cloudy
66° 49°
10% rain — SW 8 B
FRI Nov. 20 Mostly sunny Mostly sunny
68° 53°
10% rain — SSE 12 C
How sure are we? AModels agree: highs within 4° BSome spread: within 8° CWide spread: check back
Range from the National Blend of Models percentiles · graded on Forecast Scores
AIR MAIL

Where today’s air came from

The air arriving over Lake St. Louis about 5,000 feet above the ground was over the open Pacific three days ago, and over the central Plains a day ago, about 2,650 miles back along its path. It came down from about 13,800 feet up, warming and drying as it sank. Near the ground the air came from the Canadian Prairies; at 10,000 feet, from the northern Rockies. It feels dry all the same. Traced back 72 hours through NOAA’s hourly RAP analyses and the GFS beyond them, nine paths at each of three heights.

THIS WEEK IN 2015 Nov. 17–18, 2015

The wettest two days this week has seen

4.19 inches of rain fell in two days, the most for this week of the year since records began in 1957. The next wettest, 2.96 inches, fell in 2003.

2.96″
4.19″
20032015
Source: NOAA RCC-ACIS, the Weldon Spring Nws record since 1957.
MILE2
THE GROUND

What Lake St. Louis stands on

Lake St. Louis’s center stands about 610 ft above sea level. Within three miles the land runs from 490 ft to 660 ft, a difference of 170 ft: gently rolling country. The highest named summit within 15 miles is Tavern Rock, about 880 ft, 12 miles south.

Under the town center the state geologic map shows Meramecian Series (limestone), from the Carboniferous, 324 to 359 million years old.

The section below crosses 4 rock units mapped at the surface.

Lake St. Louis, cut in half from west to east

A section west to east, 24 miles through the town center
400 ft600 ft800 ft LAKE ST. LOUIS610 ftHigh point of the line890 ftLow point420 ft ← WE →

Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 41×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.

Rock at the surface along the line

Osagean Series

Limestone. Age: Carboniferous, 324 to 359 million years old. About 9 mi of the line.

Meramecian Series

Limestone. Age: Carboniferous, 324 to 359 million years old. About 8 mi of the line.

Holocene series

Clay, silt, sand. Age: Holocene, less than 12,000 years old. About 5 mi of the line.

Cherokee Group - Cabaniss Subgroup, Krebs Subgroup

Shale, sandstone, siltstone. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.

From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.

Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.

MILE3
THE WATER

Where Lake St. Louis’s rain goes

A raindrop that lands in Lake St. Louis reaches the Gulf of America by way of Peruque Creek and the Mississippi: about 1,220 river miles.

THE WAY DOWN, TO SCALE
Lake St. Louis≈ 1,220 mi · the Gulf of America
FROM THE CENTER OF LAKE ST. LOUIS ≈ 1,220 mi to the Gulf of America Peruque Creek → Mississippi

Traced down the USGS NHDPlus V2.1 river network from the Census center point of Lake St. Louis; river miles along the main stem, rounded.

MILE5
THE ALMANAC

Lake St. Louis’s year

1991–2020 normals · records since 1957 · Weldon Spring Nws, 8 mi southeast

Lake St. Louis has a hot-summer humid continental climate. Summer afternoons average 88° in July; winter nights fall to about 21° in January. A normal year brings about 14 inches of snow; with the rain, that comes to about 44 inches of water.

39°21°45°25°55°33°67°44°76°54°84°63°88°67°87°65°80°57°68°46°55°35°44°26° JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 12 TODAY 44.4 in rain and snowmelt
Normal high to low, by month Record high to low, by day Rain by month Freezing
July, average88° / 67°high / low, the warmest month
January, average39° / 21°high / low, the coldest month
Rain and melted snow44.4 inwettest months: May and June
Snow a year13.5 insnowiest: January
Hottest on record109°FAugust 18, 2000
Coldest on record−28°FDecember 23, 1989
Wettest day on record6.39 inDecember 27, 2015
Snowiest day on record14.0 inFebruary 27, 1984
90° days a year34about 1 of them 100° or more
Nights at or below 32°104and 21 days that stay below freezing
Climate typeHot-summer humid continentalKöppen Dfa

AROUND THE RING

1Freeze seasonfrom the first fall freeze, about Oct. 28, to the last in spring, about April 11 (median dates)
2Lows below freezingNov. 22 to March 13; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 Lake St. Louis normally reaches 56° and falls to 35°. The record high is 80°, in 1989; the record low 10°, in 1986. The most rain on this date, 2.00 in, fell in 1993.

MONTH BY MONTH
JanFebMarAprMayJunJulAugSepOctNovDec
Normal high39°45°55°67°76°84°88°87°80°68°55°44°
Normal low21°25°33°44°54°63°67°65°57°46°35°26°
Rain and melt, in2.612.433.744.705.094.723.923.583.503.373.693.07
Snow, inches4.13.71.70.20.00.00.00.00.00.00.83.0
Record high76° (1967)85° (1962)93° (2026)94° (2002)93° (2022)106° (2012)107° (2012)109° (2000)102° (2026)95° (1963)85° (2022)78° (2025)
Record low−23° (1977)−14° (1988)−11° (1978)18° (1989)26° (1989)39° (1989)43° (1996)36° (1986)22° (1989)19° (1981)0° (1964)−28° (1989)

Normals 1991–2020 and records since 1957 at Weldon Spring Nws, 8 miles southeast. NOAA, through RCC-ACIS.

MILE7
ON THE NETWORK

Around Lake St. Louis on the Forecast Network

Neighboring plates

O'Fallon MO · 4 MI 4 miles east St. Louis MO · 31 MI 31 miles east Columbia MO · 84 MI 84 miles west Springfield IL · 93 MI 93 miles northeast Evansville IN · 185 MI 185 miles east Independence MO · 193 MI 193 miles west
FORECASTCITY
Map of Lake St. Louis, Missouri. Explore the plate
MISSOURI · ST. CHARLES

Lake St. Louis

19,160 people, 610 ft above sea level in St. Charles County.

610 ftElevation
19,160People
9 sq miLand
Sunny 47°
SunnyDew point 25°
1

Today in Lake St. Louis

NEXT 15 HOURS
Now clear day 43° 0%
7p clear night 40° 0%
10p clear night 37° 0%
1a clear night 34° 0%
4a mostly clear night 32° 0%
7a mostly sunny 32° 0%
Clear
NEXT RAINNone this week
→
Sat0%
Sunny Sunny
30
43
A
Sun0%
Partly cloudy; warmer Partly cloudy; warmer
32
54
A
Mon0%
Sunny Sunny
35
57
A
Tue0%
Sunny Sunny
38
59
A
Wed10%
Mostly sunny Mostly sunny
47
63
B
Thu10%
Partly cloudy Partly cloudy
49
66
B
Fri10%
Mostly sunny Mostly sunny
53
68
C
Letters show how sure the forecast is: A, models agree; B, some spread; C, check back. Sample data.
THIS WEEK IN 2015 · NOV. 17–18, 2015

4.19 inches in two days, the most for this week since 1957.

2

What Lake St. Louis stands on

Lake St. Louis’s center stands about 610 ft above sea level. Within three miles the land runs from 490 ft to 660 ft, a difference of 170 ft: gently rolling country. The highest named summit within 15 miles is Tavern Rock, about 880 ft, 12 miles south.

Lake St. Louis, west to east Lake St. Louis610 ft ← WE → 24 miles through the town center; vertical exaggeration about 79×. Colors: rock at the surface.
Elevation, center610 ft
Within 3 miles490 to 660 ft
Lie of the landGently rolling (170 ft of relief)
High point nearbyTavern Rock, 880 ft, 12 mi south
Rock at the surfaceMeramecian Series
Its ageCarboniferous, 324 to 359 million years old
5

Lake St. Louis’s year

Lake St. Louis has a hot-summer humid continental climate. Summer afternoons average 88° in July; winter nights fall to about 21° in January. A normal year brings about 14 inches of snow; with the rain, that comes to about 44 inches of water.

JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 12 44.4 in
July, average88° / 67° · high / low, the warmest month
January, average39° / 21° · high / low, the coldest month
Rain and melted snow44.4 in · wettest months: May and June
Snow a year13.5 in · snowiest: January
Hottest on record109°F · August 18, 2000
Coldest on record−28°F · December 23, 1989
Wettest day on record6.39 in · December 27, 2015
Snowiest day on record14.0 in · February 27, 1984
90° days a year34 · about 1 of them 100° or more
Nights at or below 32°104 · and 21 days that stay below freezing
Climate typeHot-summer humid continental · Köppen Dfa
1Freeze season · from the first fall freeze, about Oct. 28, to the last in spring, about April 11 (median dates)
2Lows below freezing · Nov. 22 to March 13; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 Lake St. Louis normally reaches 56° and falls to 35°. The record high is 80°, in 1989; the record low 10°, in 1986. The most rain on this date, 2.00 in, fell in 1993.

Normals 1991–2020 and records since 1957 at Weldon Spring Nws, 8 miles southeast. NOAA, through RCC-ACIS.
3

Where the rain goes

≈ 1,220 mito the Gulf of AmericaPeruque Creek → Mississippi

A raindrop that lands in Lake St. Louis reaches the Gulf of America by way of Peruque Creek and the Mississippi: about 1,220 river miles.