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Shaded-relief map of Dayton, Illinois: rivers, roads, the city limits and where the water drains.
ILLINOIS · LASALLE COUNTY

Dayton

528 people, 580 ft above sea level in LaSalle County.

580 ftElevation, city center
528People, 2024 estimate
2 sq miLand area
Sunny 45°
Sunny now Dew point 26° · NNW 5 mph · high 43°
City of Dayton River Interstate 2 miles
Explore the plate Order a print

The Dayton 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 Dayton

NWS forecast and National Blend of Models · updated 3:00 PM CST
RIGHT NOW Marshall County Airport (KC75) · 3:55 PM
Sunny
45° Sunny Feels like 42° · high of 43° near 4 PM
WindNNW 5 mphno gusts
Humidity47%rising to 92% by morning
Pressure30.30 in →steady
Visibility10 mihaze-free
CloudsClear
UV index—no forecast
Dew point 26° · Dry36° by Tuesday: more humid
DryComfortableStickyMuggyOppressive
NEXT RAIN
Clear
Not this weeknone in the forecast for a week
LIKELY AMOUNT—nothing expected
LAST RAINNov. 60.01 in · 8 dry days
ALERTS & OUTLOOKS
No watches or warnings for LaSalle County
NWS Chicago and the Storm Prediction Center · checked 4:15 PM
SUN & MOON
↑ 6:42 AM4:37 PM ↓
9 h 54 m of daylight, 2 minutes less than yesterday
Waxing crescent, 26% lit. Next full moon: Nov. 24.
AIR & POLLEN
11
GOODAir quality index · fine particles
Tomorrow: None, moderate. 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
1p
4p
7p
10p
1a
4a
7a
10a
1p
4p
7p
10p
1a
4a
7a
10a
1p
clear night
clear night
clear night
mostly clear night
mostly clear night
mostly sunny
clear day
clear day
clear night
mostly clear night
mostly clear night
mostly clear night
mostly clear night
mostly sunny
clear day
mostly sunny
mostly clear night
mostly clear night
clear night
clear night
clear night
mostly sunny
clear day
clear day
TEMPERATURE °F
43°
27°
48°
28°
50°
32°
CHANCE OF RAIN
50%
WIND, MPH
2
2
0
0
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4
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HOW IT FEELS · DEW POINT
Dry: dew points 24 to 36°

The next seven days, and how sure we are

Forecast, with the range 8 in 10 ensemble members agree on Normal, about 80° / 62°
SAT Nov. 14 Sunny Sunny
43° 27°
0% rain — NW 3 A
SUN Nov. 15 Mostly sunny Mostly sunny
49° 28°
0% rain — NW 0 A
MON Nov. 16 Mostly sunny Mostly sunny
52° 32°
0% rain — SW 3 A
TUE Nov. 17 Sunny Sunny
55° 36°
0% rain — S 5 A
WED Nov. 18 Mostly sunny Mostly sunny
57° 45°
10% rain — S 9 B
THU Nov. 19 Mostly sunny Mostly sunny
61° 45°
20% rain — WSW 5 C
FRI Nov. 20 Partly cloudy Partly cloudy
62° 50°
20% rain — SE 6 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 Dayton about 5,000 feet above the ground was over the open Pacific three days ago, and over the northern Plains a day ago, about 2,870 miles back along its path. It came down from about 13,000 feet up, warming and drying as it sank. Near the ground the air came from the Canadian Prairies; at 10,000 feet, from the open Pacific. 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, FOUR YEARS AGO Nov. 11, 2022

The hottest this week has been

75° on Nov. 11, 2022, the hottest reading for this week of the year since 1941. Next is 74° in 2020.

74°
75°
20202022
Source: NOAA RCC-ACIS, the Marseilles Lock/Dam record since 1941.
MILE2
THE GROUND

What Dayton stands on

Dayton’s center stands about 580 ft above sea level. Within three miles the land runs from 460 ft to 660 ft, a difference of 200 ft: gently rolling country.

Under the town center the state geologic map shows Carbondale Formation (shale, sandstone, coal), from the Middle Pennsylvanian to Late Pennsylvanian, 304 to 315 million years old.

The section below crosses 3 rock units mapped at the surface.

Dayton, cut in half from west to east

A section west to east, 24 miles through the town center
500 ft600 ft700 ft DAYTON580 ftStarved Rock600 ftHigh point of the line740 ft ← W · North UticaE →

Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 63×. 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

Carbondale Formation

Shale, sandstone, coal. Age: Middle Pennsylvanian to Late Pennsylvanian, 304 to 315 million years old. About 19 mi of the line.

Ancell Group

Sandstone, limestone, dolostone. Age: Middle Ordovician to Late Ordovician, 454 to 468 million years old. About 5 mi of the line.

Prairie du Chien Group

Dolostone. Age: Early Ordovician to Middle Ordovician, 459 to 487 million years old. About 0.6 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 Dayton’s rain goes

A raindrop that lands in Dayton reaches the Gulf of America by way of the Fox River, the Illinois and the Mississippi: about 1,440 river miles.

THE WAY DOWN, TO SCALE
Dayton≈ 1,440 mi · the Gulf of America
FROM THE CENTER OF DAYTON ≈ 1,440 mi to the Gulf of America Fox River → Illinois → Mississippi

Lake on the way: Peoria Lake.

1,190 miles of the trip are on the Mississippi.

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

MILE5
THE ALMANAC

Dayton’s year

1991–2020 normals · records since 1941 · Marseilles Lock/Dam, 4 mi south-southeast

Dayton has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 14° in January. A normal year brings about 25 inches of snow; with the rain, that comes to about 39 inches of water.

31°14°36°17°47°27°61°37°73°49°81°58°84°62°82°61°77°53°64°41°49°30°37°21° JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 1234 TODAY DAYTON 39.0 in rain and snowmelt
Normal high to low, by month Rain by month Freezing
July, average84° / 62°high / low, the warmest month
January, average31° / 14°high / low, the coldest month
Rain and melted snow39.0 inwettest months: June and May
Snow a year25.0 insnowiest: January
Hottest on record102°FJuly 8, 2012
Coldest on record−27°FJanuary 5, 1999
Wettest day on record6.80 inJuly 14, 1958
90° days a year15very few reach 100°
Nights at or below 32°139and 43 days that stay below freezing
Climate typeHot-summer humid continentalKöppen Dfa

AROUND THE RING

1Freeze seasonfrom the first fall freeze, about Oct. 18, to the last in spring, about April 30 (median dates)
2Highs below freezingJan. 1 to Feb. 4; normal highs stay below 32°
3Lows below freezingNov. 9 to April 1; normal lows fall below 32°
4Wettest stretchMay through July: 13.5 of the year’s 39.0 inches
MONTH BY MONTH
JanFebMarAprMayJunJulAugSepOctNovDec
Normal high31°36°47°61°73°81°84°82°77°64°49°37°
Normal low14°17°27°37°49°58°62°61°53°41°30°21°
Rain and melt, in1.951.902.543.594.704.923.854.093.463.202.722.11
Snow, inches8.47.32.90.30.00.00.00.00.00.00.85.3

Normals 1991–2020 and records since 1941 at Marseilles Lock/Dam, 4 miles south-southeast. NOAA, through RCC-ACIS.

MILE7
ON THE NETWORK

Around Dayton on the Forecast Network

Neighboring plates

Joliet IL · 35 MI 35 miles east Aurora IL · 37 MI 37 miles northeast Chicago IL · 65 MI 65 miles northeast Madison WI · 121 MI 121 miles north Milwaukee WI · 123 MI 123 miles north Indianapolis IN · 178 MI 178 miles southeast
FORECASTCITY
Map of Dayton, Illinois. Explore the plate
ILLINOIS · LASALLE

Dayton

528 people, 580 ft above sea level in LaSalle County.

580 ftElevation
528People
2 sq miLand
Sunny 45°
SunnyDew point 26°
1

Today in Dayton

NEXT 15 HOURS
Now clear day 43° 0%
7p clear night 35° 0%
10p clear night 31° 0%
1a mostly clear night 29° 0%
4a mostly clear night 27° 0%
7a mostly sunny 27° 0%
Clear
NEXT RAINNone this week
→
Sat0%
Sunny Sunny
27
43
A
Sun0%
Mostly sunny Mostly sunny
28
49
A
Mon0%
Mostly sunny Mostly sunny
32
52
A
Tue0%
Sunny Sunny
36
55
A
Wed10%
Mostly sunny Mostly sunny
45
57
B
Thu20%
Mostly sunny Mostly sunny
45
61
C
Fri20%
Partly cloudy Partly cloudy
50
62
C
Letters show how sure the forecast is: A, models agree; B, some spread; C, check back. Sample data.
THIS WEEK, FOUR YEARS AGO · NOV. 11, 2022

75°, the hottest this week of the year has been since 1941.

2

What Dayton stands on

Dayton’s center stands about 580 ft above sea level. Within three miles the land runs from 460 ft to 660 ft, a difference of 200 ft: gently rolling country.

Dayton, west to east Dayton580 ftStarved Rock600 ft ← WE → 24 miles through the town center; vertical exaggeration about 120×. Colors: rock at the surface.
Elevation, center580 ft
Within 3 miles460 to 660 ft
Lie of the landGently rolling (200 ft of relief)
Rock at the surfaceCarbondale Formation
Its ageMiddle Pennsylvanian to Late Pennsylvanian, 304 to 315 million years old
5

Dayton’s year

Dayton has a hot-summer humid continental climate. Summer afternoons average 84° in July; winter nights fall to about 14° in January. A normal year brings about 25 inches of snow; with the rain, that comes to about 39 inches of water.

JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 1234 39.0 in
July, average84° / 62° · high / low, the warmest month
January, average31° / 14° · high / low, the coldest month
Rain and melted snow39.0 in · wettest months: June and May
Snow a year25.0 in · snowiest: January
Hottest on record102°F · July 8, 2012
Coldest on record−27°F · January 5, 1999
Wettest day on record6.80 in · July 14, 1958
90° days a year15 · very few reach 100°
Nights at or below 32°139 · and 43 days that stay below freezing
Climate typeHot-summer humid continental · Köppen Dfa
1Freeze season · from the first fall freeze, about Oct. 18, to the last in spring, about April 30 (median dates)
2Highs below freezing · Jan. 1 to Feb. 4; normal highs stay below 32°
3Lows below freezing · Nov. 9 to April 1; normal lows fall below 32°
4Wettest stretch · May through July: 13.5 of the year’s 39.0 inches
Normals 1991–2020 and records since 1941 at Marseilles Lock/Dam, 4 miles south-southeast. NOAA, through RCC-ACIS.
3

Where the rain goes

≈ 1,440 mito the Gulf of AmericaFox River → Illinois → Mississippi

A raindrop that lands in Dayton reaches the Gulf of America by way of the Fox River, the Illinois and the Mississippi: about 1,440 river miles.

Lake on the way: Peoria Lake.

1,190 miles of the trip are on the Mississippi.