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

St. Jacob

1,368 people, 520 ft above sea level in Madison County.

520 ftElevation, city center
1,368People, 2024 estimate
1 sq miLand area
Clear 45°
Clear now Dew point 25° · NNW 3 mph · high 42°
City of St. Jacob River Interstate 2 miles
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The St. Jacob 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 St. Jacob

NWS forecast and National Blend of Models · updated 4:00 PM CST
RIGHT NOW St. Louis Regional Airport (KALN) · 4:50 PM
Clear
45° Clear Feels like 43° · high of 42° near 5 PM
WindNNW 3 mphno gusts
Humidity45%rising to 88% by morning
Pressure30.30 in →steady
Visibility10 mihaze-free
CloudsClear
UV index—no forecast
Dew point 25° · Dry39° by Tuesday: more humid
DryComfortableStickyMuggyOppressive
NEXT RAIN
Clear
Not this weeknone in the forecast for a week
LIKELY AMOUNT—nothing expected
LAST RAINNov. 50.02 in · 9 dry days
ALERTS & OUTLOOKS
No watches or warnings for Madison County
NWS St Louis and the Storm Prediction Center · checked 5:15 PM
SUN & MOON
↑ 6:40 AM4:46 PM ↓
10 h 6 m of daylight, 2 minutes less than yesterday
Waxing crescent, 26% lit. Next full moon: Nov. 24.
AIR & POLLEN
23
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
5p
8p
11p
2a
5a
8a
11a
2p
5p
8p
11p
2a
5a
8a
11a
2p
5p
8p
11p
2a
5a
8a
11a
2p
clear night
clear night
clear night
clear night
mostly clear night
partly cloudy day
partly cloudy day
mostly sunny
clear night
clear night
mostly clear night
mostly clear night
clear night
clear day
clear day
clear day
clear night
clear night
clear night
clear night
mostly clear night
mostly sunny
clear day
clear day
TEMPERATURE °F
42°
27°
51°
30°
53°
32°
CHANCE OF RAIN
50%
WIND, MPH
2
0
0
0
0
0
0
0
0
0
0
0
0
0
3
2
0
0
0
0
0
3
7
8
HOW IT FEELS · DEW POINT
Dry: dew points 24 to 30° ↑ Humid air returns More humid: 37° by Tuesday

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
42° 25°
0% rain — N 1 A
SUN Nov. 15 Partly cloudy; warmer Partly cloudy; warmer
54° 27°
0% rain — NNE 0 A
MON Nov. 16 Sunny Sunny
55° 29°
0% rain — S 2 A
TUE Nov. 17 Sunny Sunny
57° 32°
0% rain — SE 7 A
WED Nov. 18 Mostly sunny Mostly sunny
61° 43°
0% rain — SSE 12 B
THU Nov. 19 Mostly sunny Mostly sunny
65° 45°
10% rain — SW 7 C
FRI Nov. 20 Mostly sunny Mostly sunny
67° 48°
0% 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 St. Jacob about 5,000 feet above the ground was over the open Pacific three days ago, about 3,040 miles back along its path. It came down from about 15,000 feet up, warming and drying as it sank. Near the ground the air came from the Canadian Prairies; at 10,000 feet, from the central Plains. 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 1959 Nov. 17, 1959

The coldest this week has been

7° on Nov. 17, 1959, the coldest reading for this week of the year since 1948. Next is 8° in 2019.

8°
7°
20191959
Source: NOAA RCC-ACIS, the Belleville Siu Research record since 1948.
MILE2
THE GROUND

What St. Jacob stands on

St. Jacob’s center stands about 520 ft above sea level. Within three miles the land runs from 460 ft to 560 ft, a difference of 100 ft: gently rolling country.

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.

St. Jacob, cut in half from southwest to northeast

A section southwest to northeast, 24 miles through the town center
400 ft500 ft ST. JACOB520 ftLow point420 ftLebanon470 ftHigh point of the line580 ft ← SW · Scott AFBNE →

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 14 mi of the line.

Bond Formation

Shale, sandstone, limestone. Age: Late Pennsylvanian, 304 to 307 million years old. About 10 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 St. Jacob’s rain goes

A raindrop that lands in St. Jacob reaches the Gulf of America by way of Lake Fork, Silver Creek, the Kaskaskia and the Mississippi: about 1,160 river miles.

THE WAY DOWN, TO SCALE
St. Jacob≈ 1,160 mi · the Gulf of America
FROM THE CENTER OF ST. JACOB ≈ 1,160 mi to the Gulf of America Lake Fork → Silver Creek → Kaskaskia → Mississippi

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

MILE5
THE ALMANAC

St. Jacob’s year

1991–2020 normals · records since 1948 · Belleville Siu Research, 14 mi south-southwest

St. Jacob has a humid subtropical climate. Summer afternoons average 90° in July; winter nights fall to about 24° in January. A normal year brings about 11 inches of snow; with the rain, that comes to about 43 inches of water.

43°24°49°28°59°36°71°46°79°56°87°64°90°68°89°65°83°57°73°47°58°37°46°28° JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 123 TODAY ST. JACOB 43.4 in rain and snowmelt
Normal high to low, by month Record high to low, by day Rain by month Freezing
July, average90° / 68°high / low, the warmest month
January, average43° / 24°high / low, the coldest month
Rain and melted snow43.4 inwettest months: May and April
Snow a year11.2 insnowiest: January
Hottest on record110°FJuly 14, 1954
Coldest on record−27°FJanuary 17, 1977
Wettest day on record8.15 inJune 15, 1957
Snowiest day on record14.8 inJanuary 31, 1982
90° days a year53about 2 of them 100° or more
Nights at or below 32°93and 15 days that stay below freezing
Climate typeHumid subtropicalKöppen Cfa

AROUND THE RING

1Freeze seasonfrom the first fall freeze, about Oct. 14, to the last in spring, about April 12 (median dates)
2Highs of 90° and upJune 28 to Aug. 14; normal highs reach 90°
3Lows below freezingNov. 29 to March 3; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 St. Jacob normally reaches 59° and falls to 37°. The record high is 82°, in 1999; the record low 11°, in 1986. The most rain on this date, 3.23 in, fell in 1993.

MONTH BY MONTH
JanFebMarAprMayJunJulAugSepOctNovDec
Normal high43°49°59°71°79°87°90°89°83°73°58°46°
Normal low24°28°36°46°56°64°68°65°57°47°37°28°
Rain and melt, in2.562.163.444.905.054.624.033.923.353.123.602.61
Snow, inches3.43.31.00.00.00.00.00.00.00.00.62.9
Record high75° (1950)83° (2024)92° (2026)91° (2007)97° (1953)106° (2012)110° (1954)105° (2007)103° (1954)96° (2019)84° (2016)78° (2025)
Record low−27° (1977)−21° (1982)−8° (1978)18° (2007)28° (1976)38° (1972)43° (1972)39° (1986)26° (1995)19° (2024)2° (1991)−19° (1989)

Normals 1991–2020 and records since 1948 at Belleville Siu Research, 14 miles south-southwest. NOAA, through RCC-ACIS.

MILE7
ON THE NETWORK

Around St. Jacob on the Forecast Network

Neighboring plates

St. Louis MO · 27 MI 27 miles west Florissant MO · 31 MI 31 miles west Springfield IL · 74 MI 74 miles north Evansville IN · 131 MI 131 miles southeast Columbia MO · 139 MI 139 miles west Clarksville TN · 199 MI 199 miles southeast
FORECASTCITY
Map of St. Jacob, Illinois. Explore the plate
ILLINOIS · MADISON

St. Jacob

1,368 people, 520 ft above sea level in Madison County.

520 ftElevation
1,368People
1 sq miLand
Clear 45°
ClearDew point 25°
1

Today in St. Jacob

NEXT 15 HOURS
Now clear night 42° 0%
8p clear night 35° 0%
11p clear night 31° 0%
2a clear night 29° 0%
5a mostly clear night 27° 0%
8a partly cloudy day 33° 0%
Clear
NEXT RAINNone this week
→
Sat0%
Sunny Sunny
25
42
A
Sun0%
Partly cloudy; warmer Partly cloudy; warmer
27
54
A
Mon0%
Sunny Sunny
29
55
A
Tue0%
Sunny Sunny
32
57
A
Wed0%
Mostly sunny Mostly sunny
43
61
B
Thu10%
Mostly sunny Mostly sunny
45
65
C
Fri0%
Mostly sunny Mostly sunny
48
67
C
Letters show how sure the forecast is: A, models agree; B, some spread; C, check back. Sample data.
THIS WEEK IN 1959 · NOV. 17, 1959

7°, the coldest this week of the year has been since 1948.

2

What St. Jacob stands on

St. Jacob’s center stands about 520 ft above sea level. Within three miles the land runs from 460 ft to 560 ft, a difference of 100 ft: gently rolling country.

St. Jacob, southwest to northeast St. Jacob520 ftHigh point580 ft ← SWNE → 24 miles through the town center; vertical exaggeration about 122×. Colors: rock at the surface.
Elevation, center520 ft
Within 3 miles460 to 560 ft
Lie of the landGently rolling (100 ft of relief)
Rock at the surfaceShelburn-Patoka Formations undivided
Its ageLate Pennsylvanian, 304 to 307 million years old
5

St. Jacob’s year

St. Jacob has a humid subtropical climate. Summer afternoons average 90° in July; winter nights fall to about 24° in January. A normal year brings about 11 inches of snow; with the rain, that comes to about 43 inches of water.

JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 123 43.4 in
July, average90° / 68° · high / low, the warmest month
January, average43° / 24° · high / low, the coldest month
Rain and melted snow43.4 in · wettest months: May and April
Snow a year11.2 in · snowiest: January
Hottest on record110°F · July 14, 1954
Coldest on record−27°F · January 17, 1977
Wettest day on record8.15 in · June 15, 1957
Snowiest day on record14.8 in · January 31, 1982
90° days a year53 · about 2 of them 100° or more
Nights at or below 32°93 · and 15 days that stay below freezing
Climate typeHumid subtropical · Köppen Cfa
1Freeze season · from the first fall freeze, about Oct. 14, to the last in spring, about April 12 (median dates)
2Highs of 90° and up · June 28 to Aug. 14; normal highs reach 90°
3Lows below freezing · Nov. 29 to March 3; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 St. Jacob normally reaches 59° and falls to 37°. The record high is 82°, in 1999; the record low 11°, in 1986. The most rain on this date, 3.23 in, fell in 1993.

Normals 1991–2020 and records since 1948 at Belleville Siu Research, 14 miles south-southwest. NOAA, through RCC-ACIS.
3

Where the rain goes

≈ 1,160 mito the Gulf of AmericaLake Fork → Silver Creek → Kaskaskia → Mississippi

A raindrop that lands in St. Jacob reaches the Gulf of America by way of Lake Fork, Silver Creek, the Kaskaskia and the Mississippi: about 1,160 river miles.