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

Williamsville

1,441 people, 590 ft above sea level in Sangamon County.

590 ftElevation, city center
1,441People, 2024 estimate
2 sq miLand area
Sunny 46°
Sunny now Dew point 23° · NW 6 mph · high 44°
City of Williamsville River Interstate 2 miles
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The Williamsville 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 Williamsville

NWS forecast and National Blend of Models · updated 3:00 PM CST
RIGHT NOW Springfield - Abraham Lincoln Capital Airport (KSPI) · 3:52 PM
Sunny
46° Sunny Feels like 43° · high of 44° near 4 PM
WindNW 6 mphno gusts
Humidity40%rising to 92% by morning
Pressure30.30 in →steady
Visibility10 mihaze-free
CloudsClear
UV index—no forecast
Dew point 23° · Dry37° 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 Sangamon County
NWS Lincoln and the Storm Prediction Center · checked 4:16 PM
SUN & MOON
↑ 6:42 AM4:43 PM ↓
10 h 1 m of daylight, 2 minutes less than yesterday
Waxing crescent, 26% lit. Next full moon: Nov. 24.
AIR & POLLEN
9
GOODAir quality index · fine particles
Tomorrow: None, good. 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
clear night
mostly clear night
mostly sunny
mostly sunny
mostly sunny
clear night
clear night
clear night
mostly clear night
mostly clear night
clear day
clear day
clear day
mostly clear night
clear night
clear night
clear night
mostly clear night
mostly sunny
clear day
clear day
TEMPERATURE °F
44°
26°
50°
28°
52°
32°
CHANCE OF RAIN
50%
WIND, MPH
3
0
0
0
0
0
0
0
0
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0
2
3
2
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HOW IT FEELS · DEW POINT
Dry: dew points 24 to 28° ↑ Humid air returns More humid: 32° by Tuesday

The next seven days, and how sure we are

Forecast, with the range 8 in 10 ensemble members agree on Normal, about 53° / 35°
SAT Nov. 14 Sunny Sunny
44° 24°
0% rain — NNW 5 A
SUN Nov. 15 Mostly sunny; warmer Mostly sunny; warmer
53° 25°
0% rain — N 0 A
MON Nov. 16 Sunny Sunny
56° 29°
0% rain — SSW 2 A
TUE Nov. 17 Partly cloudy Partly cloudy
57° 32°
0% rain — SSE 7 A
WED Nov. 18 Mostly sunny Mostly sunny
60° 43°
0% rain — S 12 B
THU Nov. 19 Partly cloudy Partly cloudy
64° 45°
20% rain — WSW 7 C
FRI Nov. 20 Mostly sunny Mostly sunny
66° 49°
10% rain — SSE 9 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 Williamsville about 5,000 feet above the ground was over the open Pacific three days ago, and over the central Plains a day ago, about 3,080 miles back along its path. It came down from about 15,100 feet up, warming and drying as it sank. Near the ground the air came from the Canadian Prairies; at 10,000 feet, from British Columbia. 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, TEN YEARS AGO Nov. 17, 2016

The hottest this week has been

79° on Nov. 17, 2016, the hottest reading for this week of the year since 1879. Next is 78° in 1955.

78°
79°
19552016
Source: NOAA RCC-ACIS, the Springfield Area threaded record since 1879.
MILE2
THE GROUND

What Williamsville stands on

Williamsville’s center stands about 590 ft above sea level. Within three miles the land runs from 560 ft to 610 ft, a difference of 50 ft: nearly flat ground. The highest named summit within 15 miles is Elkhart Hill, about 820 ft, 6 miles northeast.

Under the town center the state geologic map shows Shelburn-Patoka Formations undivided (shale, limestone), from the Late Pennsylvanian, 304 to 307 million years old.

The section below crosses 2 rock units mapped at the surface.

Williamsville, cut in half from south to north

A section south to north, 24 miles through the town center
500 ft600 ft WILLIAMSVILLE590 ftRiverton560 ftWalnut Hill640 ftPolecat Hill660 ft ← S · RochesterN →

Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. 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

Shelburn-Patoka Formations undivided

Shale, limestone. Age: Late Pennsylvanian, 304 to 307 million years old. About 21 mi of the line.

Carbondale Formation

Shale, sandstone, coal. Age: Middle Pennsylvanian to Late Pennsylvanian, 304 to 315 million years old. About 3 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 Williamsville’s rain goes

A raindrop that lands in Williamsville reaches the Gulf of America by way of Wolf Creek, the Sangamon, the Illinois and the Mississippi: about 1,370 river miles.

THE WAY DOWN, TO SCALE
Williamsville≈ 1,370 mi · the Gulf of America
FROM THE CENTER OF WILLIAMSVILLE ≈ 1,370 mi to the Gulf of America Wolf Creek → Sangamon → Illinois → Mississippi

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

MILE5
THE ALMANAC

Williamsville’s year

1991–2020 normals · records since 1879 · Springfield Abraham Lincoln Capital Airport, 11 mi southwest

Williamsville has a hot-summer humid continental climate. Summer afternoons average 87° in July; winter nights fall to about 20° in January. A normal year brings about 22 inches of snow; with the rain, that comes to about 38 inches of water.

36°20°41°24°53°33°66°43°76°54°84°63°87°66°85°64°80°56°67°45°53°34°41°25° JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 123 TODAY 38.0 in rain and snowmelt
Normal high to low, by month Record high to low, by day Rain by month Freezing
July, average87° / 66°high / low, the warmest month
January, average36° / 20°high / low, the coldest month
Rain and melted snow38.0 inwettest months: June and May
Snow a year21.8 insnowiest: January
Hottest on record112°FJuly 14, 1954
Coldest on record−24°FFebruary 13, 1905
Wettest day on record5.59 inAugust 12, 2016
Snowiest day on record17.0 inMarch 24, 2013
90° days a year28very few reach 100°
Nights at or below 32°111and 30 days that stay below freezing
Climate typeHot-summer humid continentalKöppen Dfa

AROUND THE RING

1Freeze seasonfrom the first fall freeze, about Oct. 13, to the last in spring, about April 14 (median dates)
2Lows below freezingNov. 21 to March 13; normal lows fall below 32°
3Wettest stretchApril through June: 13.1 of the year’s 38.0 inches
NOVEMBER 14 IN THE RECORD

On November 14 Williamsville normally reaches 53° and falls to 35°. The record high is 78°, in 2025; the record low 12°, in 1940. The most rain on this date, 0.91 in, fell in 1993.

MONTH BY MONTH
JanFebMarAprMayJunJulAugSepOctNovDec
Normal high36°41°53°66°76°84°87°85°80°67°53°41°
Normal low20°24°33°43°54°63°66°64°56°45°34°25°
Rain and melt, in2.031.932.763.974.524.613.853.372.883.262.712.15
Snow, inches6.76.13.10.30.00.00.00.00.00.11.24.3
Record high73° (1909)80° (2024)92° (2026)90° (1986)101° (1934)104° (1934)112° (1954)108° (1934)102° (2011)93° (2006)83° (1950)74° (2012)
Record low−22° (1884)−24° (1905)−12° (1960)16° (2018)28° (1966)39° (2003)48° (2013)43° (1986)31° (1899)13° (1925)−3° (1964)−21° (1989)

Normals 1991–2020 and records since 1879 from the Springfield Area threaded record (Springfield Abraham Lincoln Capital Airport, 11 miles southwest). NOAA, through RCC-ACIS.

MILE7
ON THE NETWORK

Around Williamsville on the Forecast Network

Neighboring plates

Springfield IL · 13 MI 13 miles southwest Decatur IL · 33 MI 33 miles east St. Louis MO · 99 MI 99 miles south Joliet IL · 130 MI 130 miles northeast Cedar Rapids IA · 178 MI 178 miles northwest Indianapolis IN · 181 MI 181 miles east
FORECASTCITY
Map of Williamsville, Illinois. Explore the plate
ILLINOIS · SANGAMON

Williamsville

1,441 people, 590 ft above sea level in Sangamon County.

590 ftElevation
1,441People
2 sq miLand
Sunny 46°
SunnyDew point 23°
1

Today in Williamsville

NEXT 15 HOURS
Now clear day 44° 0%
7p clear night 36° 0%
10p clear night 31° 0%
1a clear night 28° 0%
4a mostly clear night 27° 0%
7a partly cloudy day 26° 0%
Clear
NEXT RAINNone this week
→
Sat0%
Sunny Sunny
24
44
A
Sun0%
Mostly sunny; warmer Mostly sunny; warmer
25
53
A
Mon0%
Sunny Sunny
29
56
A
Tue0%
Partly cloudy Partly cloudy
32
57
A
Wed0%
Mostly sunny Mostly sunny
43
60
B
Thu20%
Partly cloudy Partly cloudy
45
64
C
Fri10%
Mostly sunny Mostly sunny
49
66
C
Letters show how sure the forecast is: A, models agree; B, some spread; C, check back. Sample data.
THIS WEEK, TEN YEARS AGO · NOV. 17, 2016

79°, the hottest this week of the year has been since 1879.

2

What Williamsville stands on

Williamsville’s center stands about 590 ft above sea level. Within three miles the land runs from 560 ft to 610 ft, a difference of 50 ft: nearly flat ground. The highest named summit within 15 miles is Elkhart Hill, about 820 ft, 6 miles northeast.

Williamsville, south to north Williamsville590 ftWalnut Hill640 ftPolecat Hill660 ft ← SN → 24 miles through the town center; vertical exaggeration about 122×. Colors: rock at the surface.
Elevation, center590 ft
Within 3 miles560 to 610 ft
Lie of the landNearly flat (50 ft of relief)
High point nearbyElkhart Hill, 820 ft, 6 mi northeast
Rock at the surfaceShelburn-Patoka Formations undivided
Its ageLate Pennsylvanian, 304 to 307 million years old
5

Williamsville’s year

Williamsville has a hot-summer humid continental climate. Summer afternoons average 87° in July; winter nights fall to about 20° in January. A normal year brings about 22 inches of snow; with the rain, that comes to about 38 inches of water.

JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 123 38.0 in
July, average87° / 66° · high / low, the warmest month
January, average36° / 20° · high / low, the coldest month
Rain and melted snow38.0 in · wettest months: June and May
Snow a year21.8 in · snowiest: January
Hottest on record112°F · July 14, 1954
Coldest on record−24°F · February 13, 1905
Wettest day on record5.59 in · August 12, 2016
Snowiest day on record17.0 in · March 24, 2013
90° days a year28 · very few reach 100°
Nights at or below 32°111 · and 30 days that stay below freezing
Climate typeHot-summer humid continental · Köppen Dfa
1Freeze season · from the first fall freeze, about Oct. 13, to the last in spring, about April 14 (median dates)
2Lows below freezing · Nov. 21 to March 13; normal lows fall below 32°
3Wettest stretch · April through June: 13.1 of the year’s 38.0 inches
NOVEMBER 14 IN THE RECORD

On November 14 Williamsville normally reaches 53° and falls to 35°. The record high is 78°, in 2025; the record low 12°, in 1940. The most rain on this date, 0.91 in, fell in 1993.

Normals 1991–2020 and records since 1879 from the Springfield Area threaded record (Springfield Abraham Lincoln Capital Airport, 11 miles southwest). NOAA, through RCC-ACIS.
3

Where the rain goes

≈ 1,370 mito the Gulf of AmericaWolf Creek → Sangamon → Illinois → Mississippi

A raindrop that lands in Williamsville reaches the Gulf of America by way of Wolf Creek, the Sangamon, the Illinois and the Mississippi: about 1,370 river miles.