Heidelberg, Kentucky climate: Climate normals at a NOAA weather station
Heidelberg's normal year runs from 25°F January nights to 86°F July afternoons, with 49.7 inches of precipitation and 18 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 13.1°C, January lows of −4°C, July highs of 30°C, 1,262 mm of precipitation a year.
- NOAA stationHeidelberg
- Station IDUSC00153741
- Location37.55°N 83.77°W
- Elevation665 ft (203 m)
On October 23, the normal high in Heidelberg is 67°F and the normal low 41°F, and the chance of measurable rain or snow is 31%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Heidelberg.
- Jan 44° 25°
- Feb 48° 27°
- Mar 58° 33°
- Apr 69° 42°
- May 76° 52°
- Jun 83° 61°
- Jul 86° 65°
- Aug 85° 64°
- Sep 81° 56°
- Oct 70° 44°
- Nov 58° 34°
- Dec 47° 28°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Heidelberg each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 25°F. The most precipitation falls in May (5.18 in), the least in November (3.04 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 44°F | 25°F | 34.3°F | 4.00 | 6.7 | 15 | <1 | 23 | 9 h 50 min |
| February | 48°F | 27°F | 37.2°F | 4.05 | 5.3 | 12 | <1 | 22 | 10 h 50 min |
| March | 58°F | 33°F | 45.6°F | 4.38 | 2.9 | 14 | <1 | 17 | 11 h 50 min |
| April | 69°F | 42°F | 55.6°F | 4.53 | 0.1 | 13 | <1 | 6 | 13 h 10 min |
| May | 76°F | 52°F | 64.0°F | 5.18 | 0.0 | 14 | <1 | <1 | 14 h 10 min |
| June | 83°F | 61°F | 72.1°F | 4.98 | 0.0 | 13 | 3 | <1 | 14 h 40 min |
| July | 86°F | 65°F | 75.6°F | 4.30 | 0.0 | 12 | 9 | <1 | 14 h 30 min |
| August | 85°F | 64°F | 74.5°F | 3.92 | 0.0 | 10 | 10 | <1 | 13 h 40 min |
| September | 81°F | 56°F | 68.5°F | 3.51 | 0.0 | 9 | 4 | <1 | 12 h 30 min |
| October | 70°F | 44°F | 56.6°F | 3.34 | 0.0 | 9 | <1 | 6 | 11 h 20 min |
| November | 58°F | 34°F | 45.9°F | 3.04 | 0.4 | 11 | <1 | 13 | 10 h 10 min |
| December | 47°F | 28°F | 37.7°F | 4.45 | 2.8 | 14 | <1 | 24 | 9 h 40 min |
| Year (annual) | 67°F | 44°F | 55.6°F | 49.68 | 18.2 | 146 | 26 | 110 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 7°C | −4°C | 1.3°C | 102 mm | 17 cm |
| February | 9°C | −3°C | 2.9°C | 103 mm | 13 cm |
| March | 14°C | 1°C | 7.6°C | 111 mm | 7 cm |
| April | 20°C | 6°C | 13.1°C | 115 mm | 0 cm |
| May | 24°C | 11°C | 17.8°C | 132 mm | 0 cm |
| June | 28°C | 16°C | 22.3°C | 126 mm | 0 cm |
| July | 30°C | 18°C | 24.2°C | 109 mm | 0 cm |
| August | 30°C | 18°C | 23.6°C | 100 mm | 0 cm |
| September | 27°C | 13°C | 20.3°C | 89 mm | 0 cm |
| October | 21°C | 6°C | 13.7°C | 85 mm | 0 cm |
| November | 14°C | 1°C | 7.7°C | 77 mm | 1 cm |
| December | 8°C | −2°C | 3.2°C | 113 mm | 7 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00153741; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
Which months are mildest at Heidelberg?
Normal highs sit between 65°F and 85°F in April, May, June, September and October. Of those, October has the fewest days with rain (9).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00153741.
When is the last frost at Heidelberg?
In Heidelberg, the last spring frost (32°F) comes after April 17 in half of years and after May 5 in one year in ten; the first autumn frost comes before October 22 in half of years and before October 10 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 171 year in 10 after May 5; 9 in 10 after March 31
- First autumn frost, half of years before
- October 221 year in 10 before October 10; 9 in 10 before November 5
NOAA puts the median frost-free season at 189 days, and the season without a hard freeze (28°F) at 214 days.
A hard freeze (28°F) comes after April 3 in half of springs and before November 2 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Heidelberg in zone 6b in ZIP code 41311, the nearest ZIP area.
Frost dates for every NOAA station in Kentucky · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00153741; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get at Heidelberg?
In a normal year in Heidelberg, 26 days a year reach 90°F, 110 nights fall to 32°F or colder and 146 days bring measurable precipitation.
- Days at 90°F or more
- 26a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 110a normal year
- Days that stay below freezing
- 14high of 32°F or less
- Days with 0.01 inch of precipitation
- 146a normal year
- Days with 1 inch of snow or more
- 6a normal year
The highest temperature in this station's record (since 1933) is 105°F, on July 10, 1988; the lowest is −27°F, on January 20, 1994.
The wettest calendar year on that record is 1989, with 67.66 in; the snowiest season is 1959–60, with 51.1 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00153741; records: ACIS (NOAA Regional Climate Centers), station USC00153741. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Heidelberg?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds at Heidelberg, 4.1 kWh per square metre a day. August is the sunniest month (78%) and February the cloudiest (60%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 61% | 2.0 |
| February | 60% | 2.6 |
| March | 65% | 3.7 |
| April | 71% | 5.0 |
| May | 72% | 5.6 |
| June | 77% | 6.2 |
| July | 76% | 5.9 |
| August | 78% | 5.5 |
| September | 77% | 4.6 |
| October | 73% | 3.4 |
| November | 71% | 2.5 |
| December | 61% | 1.8 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How many heating and cooling degree days does Heidelberg record?
A normal year at Heidelberg brings 4,509 heating degree days, 16% fewer than the median U.S. place (5,373), and 1,123 cooling degree days, 24% more than the median (908). Six months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,849 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 950 | 0 |
| February | 779 | 0 |
| March | 606 | 4 |
| April | 305 | 23 |
| May | 113 | 82 |
| June | 12 | 224 |
| July | 0 | 329 |
| August | 2 | 294 |
| September | 42 | 147 |
| October | 280 | 18 |
| November | 574 | 1 |
| December | 847 | 0 |
| Year (annual) | 4,509 | 1,123 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00153741. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
How does Heidelberg's climate compare?
Heidelberg is warmer than 29 of the 68 places with their own NOAA record in Kentucky, and wetter than 20. Across the 7,247 U.S. stations with normals, its annual mean of 55.6°F is warmer than 62%.
In the Köppen classification computed from these normals, Heidelberg is Cfa: temperate, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Heidelberg share this climate record?
Booneville has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Booneville, KY158 people · 7 mi SE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Heidelberg's climate
What is the coldest month at Heidelberg?
January, with a normal high of 44°F and a normal low of 25°F. The warmest is July (86°F by day, 65°F at night).
Does it snow at Heidelberg?
Yes: 18 inches in a normal year, falling on 11 days with 0.1 inch or more, the most in January (6.7 inches).
What is the rainiest month at Heidelberg?
May, with 5.18 in of precipitation in a normal year; the driest is November with 3.04 in.
What plant hardiness zone is Heidelberg in?
The USDA's 2023 map puts Heidelberg in zone 6b in ZIP code 41311, the nearest ZIP area.
How late can frost come at Heidelberg?
In half of years the last 32°F night comes after April 17; in one year in ten it comes after May 5. Waiting until May 5 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Kentucky climateThe statewide normals and every place in the state
- Beattyville, KY6 miles from this station, 55.3°F a year
- Booneville (12 mi SW), KY13 miles from this station, 54.9°F a year
- Oneida, KY21 miles from this station, 56.1°F a year
- Buckhorn, KY22 miles from this station, 56.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made