Princeton, Kentucky climate: Normal weather by month, frost dates and records
Princeton's normal year runs from 27°F January nights to 89°F July afternoons, with 50.9 inches of precipitation and 9 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 14.8°C, January lows of −3°C, July highs of 32°C, 1,292 mm of precipitation a year.
- NOAA stationPrinceton (1 mi SE)
- Station IDUSC00156580
- Location37.12°N 87.87°W
- Elevation497 ft (152 m)
- Population6,223
On October 23, the normal high in Princeton is 70°F and the normal low 45°F, and the chance of measurable rain or snow is 28%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Princeton.
- Jan 46° 27°
- Feb 51° 30°
- Mar 61° 38°
- Apr 72° 47°
- May 79° 56°
- Jun 86° 64°
- Jul 89° 68°
- Aug 89° 66°
- Sep 83° 59°
- Oct 73° 47°
- Nov 60° 37°
- Dec 49° 30°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Princeton each month?
July is the warmest month, with normal highs of 89°F; January the coldest, with normal lows of 27°F. The most precipitation falls in April (5.13 in), the least in September (3.28 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 46°F | 27°F | 36.7°F | 3.66 | 2.6 | 10 | <1 | 21 | 9 h 50 min |
| February | 51°F | 30°F | 40.6°F | 4.05 | 2.7 | 10 | <1 | 16 | 10 h 50 min |
| March | 61°F | 38°F | 49.1°F | 4.75 | 1.4 | 11 | <1 | 10 | 11 h 50 min |
| April | 72°F | 47°F | 59.2°F | 5.13 | 0.0 | 11 | <1 | 2 | 13 h 10 min |
| May | 79°F | 56°F | 67.4°F | 4.79 | 0.0 | 11 | 1 | <1 | 14 h 10 min |
| June | 86°F | 64°F | 75.1°F | 4.47 | 0.0 | 10 | 10 | <1 | 14 h 40 min |
| July | 89°F | 68°F | 78.5°F | 4.53 | 0.0 | 9 | 17 | <1 | 14 h 30 min |
| August | 89°F | 66°F | 77.3°F | 3.51 | 0.0 | 8 | 15 | <1 | 13 h 40 min |
| September | 83°F | 59°F | 70.9°F | 3.28 | 0.0 | 7 | 7 | <1 | 12 h 30 min |
| October | 73°F | 47°F | 60.0°F | 4.07 | 0.1 | 8 | <1 | 2 | 11 h 20 min |
| November | 60°F | 37°F | 48.5°F | 4.09 | 0.1 | 9 | <1 | 10 | 10 h 10 min |
| December | 49°F | 30°F | 39.8°F | 4.55 | 1.6 | 11 | <1 | 18 | 9 h 40 min |
| Year (annual) | 70°F | 47°F | 58.6°F | 50.88 | 8.5 | 113 | 49 | 78 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 8°C | −3°C | 2.6°C | 93 mm | 7 cm |
| February | 11°C | −1°C | 4.8°C | 103 mm | 7 cm |
| March | 16°C | 3°C | 9.5°C | 121 mm | 4 cm |
| April | 22°C | 8°C | 15.1°C | 130 mm | 0 cm |
| May | 26°C | 13°C | 19.7°C | 122 mm | 0 cm |
| June | 30°C | 18°C | 23.9°C | 114 mm | 0 cm |
| July | 32°C | 20°C | 25.8°C | 115 mm | 0 cm |
| August | 31°C | 19°C | 25.2°C | 89 mm | 0 cm |
| September | 29°C | 15°C | 21.6°C | 83 mm | 0 cm |
| October | 23°C | 8°C | 15.6°C | 103 mm | 0 cm |
| November | 15°C | 3°C | 9.2°C | 104 mm | 0 cm |
| December | 10°C | −1°C | 4.3°C | 116 mm | 4 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00156580; 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.
When is the best weather to visit Princeton?
Normal highs sit between 65°F and 85°F in April, May, September and October. Of those, September has the fewest days with rain (7).
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 USC00156580.
When is the last frost in Princeton?
In Princeton, the last spring frost (32°F) comes after April 11 in half of years and after April 30 in one year in ten; the first autumn frost comes before October 24 in half of years and before October 12 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 111 year in 10 after April 30; 9 in 10 after March 25
- First autumn frost, half of years before
- October 241 year in 10 before October 12; 9 in 10 before November 5
NOAA puts the median frost-free season at 196 days, and the season without a hard freeze (28°F) at 217 days.
A hard freeze (28°F) comes after March 30 in half of springs and before November 2 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Princeton in zone 7a in ZIP code 42445, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Princeton's NOAA station is in zone 7a: the coldest night of a typical year reaches 2°F (25 complete years).
Frost dates for every NOAA station in Kentucky · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00156580; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. 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 in Princeton?
In a normal year in Princeton, 49 days a year reach 90°F (2 of them 100°F or more), 78 nights fall to 32°F or colder and 113 days bring measurable precipitation.
- Days at 90°F or more
- 49a normal year
- Days at 100°F or more
- 2a normal year
- Nights at 32°F or colder
- 78a normal year
- Days that stay below freezing
- 7high of 32°F or less
- Days with 0.01 inch of precipitation
- 113a normal year
- Days with 1 inch of snow or more
- 3a normal year
The highest temperature in this station's record (since 1965) is 109°F, on July 1, 2012; the lowest is −18°F, on January 19, 1994.
The wettest calendar year on that record is 1979, with 71.61 in; the snowiest season is 1977–78, with 45.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00156580; records: ACIS (NOAA Regional Climate Centers), station USC00156580. Records use complete months only; a month missing more than three days is left out.
How sunny is Princeton?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Princeton, 4.2 kWh per square metre a day. July is the sunniest month (82%) and December the cloudiest (63%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 64% | 2.1 |
| February | 63% | 2.7 |
| March | 67% | 3.8 |
| April | 73% | 5.1 |
| May | 75% | 5.7 |
| June | 82% | 6.4 |
| July | 82% | 6.2 |
| August | 82% | 5.6 |
| September | 80% | 4.7 |
| October | 76% | 3.5 |
| November | 72% | 2.5 |
| December | 63% | 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 much heating and cooling does Princeton need?
A normal year in Princeton brings 3,853 heating degree days, 28% fewer than the median U.S. place (5,373), and 1,551 cooling degree days, 71% more than the median (908). Five months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 4,577 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 877 | 0 |
| February | 685 | 1 |
| March | 499 | 8 |
| April | 213 | 38 |
| May | 65 | 139 |
| June | 4 | 308 |
| July | 0 | 417 |
| August | 1 | 382 |
| September | 26 | 205 |
| October | 204 | 49 |
| November | 498 | 5 |
| December | 781 | 0 |
| Year (annual) | 3,853 | 1,551 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00156580. 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.
Has Princeton been warmer than normal lately?
Over 45 complete years from 1966 to 2019, the station's annual mean temperature rose at a fitted 5.3°F per century (+0.29°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Princeton's climate compare?
Princeton is warmer than 60 of the other 67 places with their own NOAA record in Kentucky, and wetter than 30. Across the 7,247 U.S. stations with normals, its annual mean of 58.6°F is warmer than 71%.
In the Köppen classification computed from these normals, Princeton 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 Princeton share this climate record?
Dawson Springs 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.
- Dawson Springs, KY2,254 people · 10 mi E
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 Princeton's climate
What is the coldest month in Princeton?
January, with a normal high of 46°F and a normal low of 27°F. The warmest is July (89°F by day, 68°F at night).
Does it snow in Princeton?
Yes: 9 inches in a normal year, falling on 4 days with 0.1 inch or more, the most in February (2.7 inches).
What is the rainiest month in Princeton?
April, with 5.13 in of precipitation in a normal year; the driest is September with 3.28 in.
What plant hardiness zone is Princeton in?
The USDA's 2023 map puts Princeton in zone 7a in ZIP code 42445, the nearest ZIP area. By the same method at Princeton's NOAA station, the coldest night of a typical year reaches 2°F (25 years, 1991-2020): zone 7a.
How late can frost come in Princeton?
In half of years the last 32°F night comes after April 11; in one year in ten it comes after April 30. Waiting until April 30 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Kentucky climateThe statewide normals and every place in the state
- Eddyville, KY12 miles from this station, 60.9°F a year
- Providence, KY20 miles from this station, 57.5°F a year
- Madisonville, KY24 miles from this station, 59.5°F a year
- Hopkinsville, KY27 miles from this station, 58.3°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made