Grand Chain Dam, IL Climate: Temperature & Rain by Month
Temperature and precipitation from NOAA NCEI 1991–2020 normals →, plus PlainClimate's derived comfort score
30-year climate normals (1991-2020) from Grand Chain Dam's primary NOAA station, GRAND CHAIN DAM 53.
The climate verdict for Grand Chain Dam
Water is the standout signal in Grand Chain Dam, Illinois: 49.4 inches of precipitation in a normal year. Against that wet profile, NOAA records an annual average of 58°F. It scores 78/100 for climate comfort (good), putting it in the top third of station-mapped location scores and exceeding 72% of them.
- 58°F
- yearly average temperature, NOAA normal
- 78/100
- comfort score, above 72% of station-mapped location scores
- 49.4"
- annual precipitation · 7" snow
- 216 days
- frost-free days per growing season
Grand Chain Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00113580 · Grand Chain Dam, IL 58°F mean · 49.4" precip
TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-MID · SWING-MID · COMF-TOP · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-MILD 58°F
- RANK-UPPER #4,734
- PHOTO-FINISH ≈ Union City
- PRCP-MID 49.4"
- SWING-MID 44°F
- COMF-TOP 78/100
- LOAD-HEAT 4,102 HDD
- STN-1 USC00113580
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Union City, TN (+ 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.
- Grand Chain Dam (this station) 58°F
- Cold Louisville Bowm…, KY 58°F
- Hot Lakeside, MO 58°F
- Near Union City, TN 58°F
- Near Panhandle, TX 58°F
Climate Living Index · Grand Chain Dam
Grand Chain Dam: 70/100 · grade B
Grand Chain Dam publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Grand Chain Dam, not an official NOAA rating. Rankings still use Comfort Score 78/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 76 calendar days | 83/100 · B |
| Frost-free season | 216 days/year | 75/100 · B |
| Annual temperature balance | 57.9°F · 9.6° from 67.5°F | 69/100 · C |
| Snowfall burden | 7.2 inches/year | 67/100 · C |
| Precipitation balance | 49.4 in · 14.4 from 35 in | 49/100 · D |
Grand Chain Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Grand Chain Dam is a temperate Köppen climate: Cfa
Coldest-month mean 34.6°F and warmest-month mean 78.9°F place this station in temperate, no dry season, hot summer climates (Cfa). Class Cfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, no dry season, hot summer.
- Köppen code
- Cfa
- Group
- Temperate
- Warmest month
- 78.9°F
- Coldest month
- 34.6°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 Grand Chain Dam sits across the climate record
Three NOAA fields for Grand Chain Dam's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 69th percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- Top 21% wettest
- Grand Chain Dam's annual total ranks in the wetter third of 6,352 measured normals.
- Seasonal temperature swing
- 55th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Grand Chain Dam compares across U.S. station-mapped locations
Grand Chain Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
78 Top 28% score exceeds 72% 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%). Below this entry.
- 60–70: 1,236 station-mapped locations (20%). Below this entry.
- 70–80: 650 station-mapped locations (11%). This entry sits in this band.
- 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
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 43°F (6°C) | 26°F (-3°C) | 35°F (1°C) | 4.2" | 2.1" | 22.9 | 0.0 |
| February | 48°F (9°C) | 30°F (-1°C) | 39°F (4°C) | 3.9" | 2.5" | 17.6 | 0.0 |
| March | 57°F (14°C) | 37°F (3°C) | 47°F (8°C) | 4.8" | 0.7" | 10.3 | 0.0 |
| April | 68°F (20°C) | 47°F (8°C) | 58°F (14°C) | 5.2" | 0.0" | 1.3 | 0.0 |
| May | 77°F (25°C) | 56°F (14°C) | 67°F (19°C) | 4.9" | 0.0" | 0.0 | 0.4 |
| June | 86°F (30°C) | 65°F (18°C) | 75°F (24°C) | 4.1" | 0.0" | 0.0 | 7.7 |
| July | 89°F (32°C) | 69°F (20°C) | 79°F (26°C) | 3.3" | 0.0" | 0.0 | 15.0 |
| August | 89°F (31°C) | 67°F (20°C) | 78°F (26°C) | 3.0" | 0.0" | 0.0 | 13.2 |
| September | 83°F (28°C) | 60°F (16°C) | 72°F (22°C) | 3.4" | 0.0" | 0.0 | 4.7 |
| October | 71°F (22°C) | 48°F (9°C) | 60°F (15°C) | 4.0" | 0.1" | 0.8 | 0.4 |
| November | 58°F (14°C) | 39°F (4°C) | 48°F (9°C) | 4.4" | 0.0" | 9.4 | 0.0 |
| December | 47°F (8°C) | 31°F (-1°C) | 39°F (4°C) | 4.2" | 1.8" | 18.0 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 89°F around July 10, short of 90°F on every date, while 76 dates carry a normal low at or below freezing, the coldest 26°F near January 16.
The freezing stretch
The normal low stays at or below 32°F into February 24, then returns to freezing around December 11, covering 76 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 36% of years recorded at least a hundredth of an inch. The driest is August 26 at 20%. Summed across the calendar, that is about 107 wet dates a year.
The widest day
October 7 carries the biggest normal gap between afternoon and dawn, 23°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Grand Chain Dam.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 2.1"
9.9 days with precipitation
Snow: 2.5"
9.5 days with precipitation
Snow: 0.7"
10.4 days with precipitation
10.1 days with precipitation
10.4 days with precipitation
9.3 days with precipitation
7.8 days with precipitation
6.4 days with precipitation
6.8 days with precipitation
Snow: 0.1"
7.7 days with precipitation
8.4 days with precipitation
Snow: 1.8"
10.0 days with precipitation
Grand Chain Dam spreads its precipitation across the year
Neither half of the year dominates here: June through August take 21% of the annual total and December through February 25%, with neither reaching the 35% that would mark a distinct wet season. Grand Chain Dam has no dry season to plan around, though it does carry a 44.3°F seasonal spread.
The gap between the wettest and driest month still matters: April averages 5.2" and August 3.0". The three wettest months together take 30% 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.
When it rains in Grand Chain Dam, it arrives in quantity
49.4" of precipitation falls across only about 107 wet days here, averaging 0.46 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.
- Days with measurable precipitation
- about 107 a year, 29% of all days
- Average depth per wet day
- 0.46 inches
- Most wet days
- March, about 10
- Fewest wet days
- August, about 6
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.
Snow reaches Grand Chain Dam, but rarely amounts to much
The normals record 7.2 inches of snow a year here, most likely in February. That is a real but marginal amount: enough that snow is part of the local record, not enough to define the winter.
A figure in this range usually reflects a handful of events that melt quickly rather than a season of accumulation; about 4 days a year record any measurable snow at all.
NOAA 1991-2020 normals. An average across thirty years can smooth away a single heavy winter, so a small annual figure does not mean a significant snowfall is impossible.
Frost Dates & Growing Season
First Fall Freeze
November 5
50% probability date
Last Spring Freeze
April 3
50% probability date
Growing Season
216 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
4,102
Higher = more heating needed
Cooling Degree Days
1,546
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside IL closest to Grand Chain Dam 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 (58°F here).
- Albuquerque, NM 58°F · 0.0°F off
- Brentwood, TN 58°F · 0.0°F off
- Buffalo, OK 58°F · 0.0°F off
- Lenoir, NC 58°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (49.4" here), excluding temperature-peer places.
- Clarksville, TX 49.4" · 0.0" off
- Elberton, GA 49.4" · 0.0" off
- Greenfield, MA 49.4" · 0.0" off
- Tiverton, RI 49.4" · 0.0" off
Data-derived climate profile
How Grand Chain Dam's climate pattern fits together
heating led · wet · mid swing
Grand Chain Dam's energy balance leans toward cold weather: 4,102 annual heating degree days against 1,546 for cooling. Its 44.3°F seasonal range still makes the monthly rows more useful than the annual average alone.
Grand Chain Dam's frost-free season lasts about 216 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
July and January mark the typical warm and cold ends of the calendar in Grand Chain Dam's middle-range seasonal profile. The measured spread is 44.3°F. The annual average is 58°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
Alongside its heating load, Grand Chain Dam carries 49.4 inches of precipitation in a normal year, inside PlainClimate's wet range. Annual snowfall totals 7.2 inches. That distinction matters because a wet annual total can arrive as rain, snow, or a mixture at different times.
These labels group NOAA 1991-2020 normals from Grand Chain Dam's primary station, so the winter figures are a thirty-year average and not a floor: a single hard season can run well below them. Treat each band as a descriptive range for Grand Chain Dam, not an official NOAA class or a year-ahead forecast.
Questions about Grand Chain Dam's climate
How much rain does Grand Chain Dam get? ▼
How many days above 90°F does Grand Chain Dam get? ▼
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Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Grand Chain Dam's primary station: GRAND CHAIN DAM 53 (USC00113580). 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 Grand Chain Dam; 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 Grand Chain Dam 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.