De Kalb, IL Climate: Temperature & Rain by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from De Kalb's primary NOAA station, DE KALB.
The climate verdict for De Kalb
De Kalb, Illinois has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 49°F. Its climate comfort score of 59/100 (moderate) lands mid-pack nationally, exceeding 37% of station-mapped location scores.
- 49°F
- yearly average temperature, NOAA normal
- 59/100
- comfort score, above 37% of station-mapped location scores
- 37.3"
- annual precipitation · 33" snow
- 177 days
- frost-free growing season
De Kalb: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00112223 · De Kalb, IL 49°F mean · 37.3" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 49°F
- RANK-COOL #2,333
- PHOTO-FINISH ≈ Comstock
- PRCP-MID 37.3"
- SWING-WIDE 53°F
- COMF-MID 59/100
- LOAD-HEAT 6,745 HDD
- STN-1 USC00112223
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Comstock, NE (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every IL station list.
- De Kalb (this station) 49°F
- Cold Ames, IA 49°F
- Hot Burwell, NE 49°F
- Near Comstock, NE 49°F
- Near Mt Carroll, IL 49°F
Climate Living Index · De Kalb
De Kalb: 51/100 · grade D
De Kalb publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for De Kalb, not an official NOAA rating. Rankings still use Comfort Score 59/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 37.3 in · 2.3 from 35 in | 91/100 · A |
| Normal heat + freeze calendar | 144 calendar days | 51/100 · D |
| Frost-free season | 177 days/year | 48/100 · D |
| Snowfall burden | 33.1 inches/year | 35/100 · F |
| Annual temperature balance | 48.6°F · 18.9° from 67.5°F | 34/100 · F |
De Kalb · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
De Kalb is a continental Köppen climate: Dfa
Coldest-month mean 20.6°F and warmest-month mean 73.2°F place this station in continental, no dry season, hot summer climates (Dfa). Class Dfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, hot summer.
- Köppen code
- Dfa
- Group
- Continental
- Warmest month
- 73.2°F
- Coldest month
- 20.6°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where De Kalb sits across the climate record
Three NOAA fields for De Kalb's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 34th percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- 52nd percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 87%
- Warmest-to-coldest month gap for De Kalb is large versus 6,861 complete station-years.
How De Kalb compares across U.S. station-mapped locations
De Kalb's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
59 37th percentile score exceeds 37% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). This entry sits in this band.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
De Kalb's measured station temperature trend
MethodologyAcross 43 complete annual observations from 1967 to 2025, DE KALB warmed at a fitted rate of 0.27°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- De Kalb primary station fitted change +0.27 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 28°F (-2°C) | 13°F (-10°C) | 21°F (-6°C) | 1.7" | 10.2" | 29.8 | 0.0 |
| February | 33°F (0°C) | 17°F (-9°C) | 25°F (-4°C) | 1.7" | 8.7" | 26.1 | 0.0 |
| March | 45°F (7°C) | 27°F (-3°C) | 36°F (2°C) | 2.2" | 4.4" | 23.0 | 0.0 |
| April | 59°F (15°C) | 37°F (3°C) | 48°F (9°C) | 3.6" | 1.3" | 8.0 | 0.0 |
| May | 70°F (21°C) | 49°F (10°C) | 60°F (15°C) | 4.8" | 0.0" | 0.5 | 0.9 |
| June | 80°F (27°C) | 60°F (15°C) | 70°F (21°C) | 4.6" | 0.0" | 0.0 | 3.6 |
| July | 83°F (28°C) | 63°F (17°C) | 73°F (23°C) | 4.0" | 0.0" | 0.0 | 4.3 |
| August | 81°F (27°C) | 61°F (16°C) | 71°F (22°C) | 4.1" | 0.0" | 0.0 | 2.8 |
| September | 75°F (24°C) | 53°F (12°C) | 64°F (18°C) | 3.3" | 0.0" | 0.3 | 1.5 |
| October | 62°F (17°C) | 41°F (5°C) | 52°F (11°C) | 3.0" | 0.1" | 5.9 | 0.0 |
| November | 46°F (8°C) | 30°F (-1°C) | 38°F (3°C) | 2.3" | 1.8" | 18.9 | 0.0 |
| December | 34°F (1°C) | 19°F (-7°C) | 26°F (-3°C) | 2.0" | 6.6" | 28.1 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 83°F around July 10, short of 90°F on every date, while 144 dates carry a normal low at or below freezing, the coldest 12°F near January 21.
The freezing stretch
The normal low stays at or below 32°F into April 1, then returns to freezing around November 10, covering 144 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is April 30, when 43% of years recorded at least a hundredth of an inch. The driest is August 24 at 29%. Summed across the calendar, that is about 122 wet dates a year.
The widest day
September 25 carries the biggest normal gap between afternoon and dawn, 22°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for De Kalb.
Where De Kalb Stands Nationally
Days and nights track unusually close together; the widest normal swing, about 22°F, is narrower than most stations record.
De Kalb earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 10.2"
9.8 days with precipitation
Snow: 8.7"
8.4 days with precipitation
Snow: 4.4"
9.8 days with precipitation
Snow: 1.3"
12.3 days with precipitation
12.9 days with precipitation
11.0 days with precipitation
10.1 days with precipitation
9.0 days with precipitation
9.0 days with precipitation
Snow: 0.1"
10.2 days with precipitation
Snow: 1.8"
8.6 days with precipitation
Snow: 6.6"
10.3 days with precipitation
De Kalb spreads its precipitation across the year
Neither half of the year dominates here: June through August take 34% of the annual total and December through February 15%, with neither reaching the 35% that would mark a distinct wet season. De Kalb has no dry season to plan around, though it does carry a wide 52.6°F gap between its warmest and coldest month.
The gap between the wettest and driest month still matters: May averages 4.8" and January 1.7". The three wettest months together take 36% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
How De Kalb's precipitation splits across the calendar
About 121 days a year record measurable precipitation here, carrying 37.3" between them, or roughly 0.31 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Winter brings real snow to De Kalb
De Kalb averages 33.1 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 24 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 33.1 inches of depth.
- Days recording measurable snow: about 24 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 9% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 18
50% probability date
Last Spring Freeze
April 24
50% probability date
Growing Season
177 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,745
Higher = more heating needed
Cooling Degree Days
790
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside IL closest to De Kalb on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (49°F here).
- Baker, NV 49°F · 0.0°F off
- Blissfield, MI 49°F · 0.0°F off
- Bloomingdale, MI 49°F · 0.0°F off
- Brockport, NY 49°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (37.3" here), excluding temperature-peer places.
- Red Oak, IA 37.2" · 0.0" off
- Webster City, IA 37.2" · 0.0" off
- Goliad, TX 37.2" · 0.0" off
- Hillsboro, WI 37.3" · 0.0" off
Snow and freeze rhythm
When cold and snow define De Kalb
heating led · moderate · mid swing
De Kalb's energy balance leans toward cold weather: 6,745 annual heating degree days against 790 for cooling. Its 52.6°F seasonal range still makes the monthly rows more useful than the annual average alone.
De Kalb's frost-free season lasts about 177 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. De Kalb coldest normal
January
Averaging 21°F (-6°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. De Kalb typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. De Kalb snow peak
January
De Kalb averages 33.1 inches of snow a year, with January the snowiest month on the normals.
Questions about De Kalb's climate
How much snow does De Kalb get? ▼
How cold does De Kalb get in winter? ▼
How much energy does heating and cooling require in De Kalb? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from De Kalb's primary station: DE KALB (USC00112223). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for De Kalb; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for De Kalb comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.