Houlton, Maine climate: Normal weather by month, frost dates and records
Houlton's normal year runs from 3°F January nights to 78°F July afternoons, with 39.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 4.8°C, January lows of −16°C, July highs of 26°C, 998 mm of precipitation a year.
- NOAA stationHoulton International Airport
- Station IDUSW00014609
- Location46.12°N 67.79°W
- Elevation476 ft (145 m)
- Population (town)6,005
- Census place4,958
On October 23, the normal high in Houlton is 51°F and the normal low 32°F, and the chance of measurable rain or snow is 41%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Houlton.
- Jan 23° 3°
- Feb 26° 3°
- Mar 36° 15°
- Apr 49° 28°
- May 64° 39°
- Jun 73° 48°
- Jul 78° 54°
- Aug 77° 52°
- Sep 68° 44°
- Oct 55° 34°
- Nov 41° 25°
- Dec 30° 12°
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 Houlton each month?
July is the warmest month, with normal highs of 78°F; January the coldest, with normal lows of 3°F. The most precipitation falls in June (4.04 in), the least in February (1.95 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 23°F | 3°F | 12.9°F | 2.65 | 11 | <1 | 30 | 9 h |
| February | 26°F | 3°F | 14.8°F | 1.95 | 10 | <1 | 27 | 10 h 20 min |
| March | 36°F | 15°F | 25.5°F | 2.67 | 11 | <1 | 29 | 11 h 50 min |
| April | 49°F | 28°F | 38.6°F | 2.94 | 12 | <1 | 22 | 13 h 30 min |
| May | 64°F | 39°F | 51.2°F | 3.46 | 13 | <1 | 8 | 15 h |
| June | 73°F | 48°F | 60.2°F | 4.04 | 14 | 1 | 1 | 15 h 40 min |
| July | 78°F | 54°F | 66.1°F | 3.63 | 13 | 1 | <1 | 15 h 30 min |
| August | 77°F | 52°F | 64.4°F | 3.52 | 12 | 1 | <1 | 14 h 10 min |
| September | 68°F | 44°F | 56.2°F | 3.40 | 11 | <1 | 4 | 12 h 40 min |
| October | 55°F | 34°F | 44.3°F | 4.04 | 13 | <1 | 16 | 11 h |
| November | 41°F | 25°F | 33.1°F | 3.61 | 12 | <1 | 24 | 9 h 30 min |
| December | 30°F | 12°F | 20.9°F | 3.37 | 13 | <1 | 30 | 8 h 40 min |
| Year (annual) | 52°F | 30°F | 40.7°F | 39.28 | 144 | 3 | 190 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −5°C | −16°C | −10.6°C | 67 mm |
| February | −3°C | −16°C | −9.6°C | 50 mm |
| March | 2°C | −9°C | −3.6°C | 68 mm |
| April | 10°C | −2°C | 3.7°C | 75 mm |
| May | 18°C | 4°C | 10.7°C | 88 mm |
| June | 23°C | 9°C | 15.7°C | 103 mm |
| July | 26°C | 12°C | 18.9°C | 92 mm |
| August | 25°C | 11°C | 18.0°C | 89 mm |
| September | 20°C | 7°C | 13.4°C | 86 mm |
| October | 13°C | 1°C | 6.8°C | 103 mm |
| November | 5°C | −4°C | 0.6°C | 92 mm |
| December | −1°C | −11°C | −6.2°C | 86 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Houlton's own co-op station Houlton (5 mi N) does: 96 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014609; 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 Houlton?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, September has the fewest days with rain (11).
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 USW00014609.
When is the last frost in Houlton?
In Houlton, the last spring frost (32°F) comes after May 27 in half of years and after June 10 in one year in ten; the first autumn frost comes before September 18 in half of years and before September 5 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
- May 271 year in 10 after June 10; 9 in 10 after May 9
- First autumn frost, half of years before
- September 181 year in 10 before September 5; 9 in 10 before October 2
NOAA puts the median frost-free season at 115 days, and the season without a hard freeze (28°F) at 143 days.
A hard freeze (28°F) comes after May 10 in half of springs and before October 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Houlton in zone 4b in ZIP code 04730, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Houlton's NOAA station is in zone 4a: the coldest night of a typical year reaches −25°F (30 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Maine · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00014609; 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 Houlton?
In a normal year in Houlton, 3 days a year reach 90°F, 190 nights fall to 32°F or colder and 144 days bring measurable precipitation.
- Days at 90°F or more
- 3a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 190a normal year
- Days that stay below freezing
- 80high of 32°F or less
- Days with 0.01 inch of precipitation
- 144a normal year
The highest temperature in this station's record (since 1948) is 99°F, on August 2, 1975; the lowest is −41°F, on January 4, 1981.
The wettest calendar year on that record is 1990, with 56.12 in; the snowiest season is 1970–71, with 165.1 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00014609; records: ACIS (NOAA Regional Climate Centers), station USW00014609. Records use complete months only; a month missing more than three days is left out.
How humid and windy is Houlton, and how clear are its skies?
The summer (June-August) dew point averages 56°F. The muggiest month is July, with an average dew point of 58°F; the driest air comes in January (5°F). February is the windiest month (8.3 mph on average).
| Month | Dew point | Humidity | Afternoon humidity | Wind | Clear or few clouds | Overcast |
|---|---|---|---|---|---|---|
| January | 5°F | 70% | 57% | 7.6 mph | – | – |
| February | 10°F | 66% | 52% | 8.3 mph | – | – |
| March | 21°F | 63% | 47% | 8.1 mph | – | – |
| April | 33°F | 62% | 41% | 7.8 mph | – | – |
| May | 46°F | 69% | 51% | 7.0 mph | – | – |
| June | 56°F | 74% | 55% | 6.4 mph | – | – |
| July | 58°F | 75% | 53% | 5.8 mph | – | – |
| August | 53°F | 75% | 54% | 6.1 mph | – | – |
| September | 44°F | 77% | 56% | 6.3 mph | – | – |
| October | 33°F | 77% | 62% | 7.4 mph | – | – |
| November | 22°F | 78% | 69% | 7.3 mph | – | – |
| December | 11°F | 74% | 65% | 7.9 mph | – | – |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014609. Monthly averages of all hours; afternoon humidity at 3 p.m. local standard time; sky as the share of hours NOAA's observations rate clear or few clouds (a dash where NOAA publishes no sky value).
How sunny is Houlton?
Over a year 67% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Houlton, 3.5 kWh per square metre a day. August is the sunniest month (73%) and December the cloudiest (58%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 65% | 1.4 |
| February | 67% | 2.3 |
| March | 67% | 3.5 |
| April | 66% | 4.5 |
| May | 65% | 5.1 |
| June | 67% | 5.5 |
| July | 71% | 5.6 |
| August | 73% | 4.9 |
| September | 73% | 3.9 |
| October | 64% | 2.4 |
| November | 59% | 1.4 |
| December | 58% | 1.1 |
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 Houlton need?
A normal year in Houlton brings 9,034 heating degree days, 68% more than the median U.S. place (5,373), and 207 cooling degree days, 77% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,636 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,615 | 0 |
| February | 1,407 | 0 |
| March | 1,225 | 0 |
| April | 792 | 0 |
| May | 432 | 5 |
| June | 177 | 35 |
| July | 54 | 88 |
| August | 81 | 62 |
| September | 283 | 17 |
| October | 644 | 1 |
| November | 959 | 0 |
| December | 1,367 | 0 |
| Year (annual) | 9,034 | 207 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014609. 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 Houlton been warmer than normal lately?
2025 averaged 41.2°F, 0.5°F above the 1991-2020 normal of 40.7°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 43.5°F | +2.8°F | 35.88 |
| 2022 | 42.8°F | +2.1°F | 43.34 |
| 2023 | 43.5°F | +2.8°F | 40.61 |
| 2024 | 44.0°F | +3.3°F | 31.33 |
| 2025 | 41.2°F | +0.5°F | 33.68 |
Over 70 complete years from 1949 to 2025, the station's annual mean temperature rose at a fitted 5.1°F per century (+0.28°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00014609; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Houlton's climate compare?
Houlton is warmer than 5 of the other 41 places with their own NOAA record in Maine, and wetter than 1. Across the 7,247 U.S. stations with normals, its annual mean of 40.7°F is warmer than 7%.
In the Köppen classification computed from these normals, Houlton is Dfb: continental, no dry season, warm 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 Houlton share this climate record?
Oakfield 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.
- Oakfield, ME659 people · 17 mi W
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Houlton's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Houlton. This page uses Houlton International Airport; the other differs by site and elevation:
| Station | From this station | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Houlton (5 mi N) USC00173944 | 6 mi N | 390 ft | 41.8°F | 3°F | 79°F | 44.1 | 96 | May 19 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Houlton's climate
What is the coldest month in Houlton?
January, with a normal high of 23°F and a normal low of 3°F. The warmest is July (78°F by day, 54°F at night).
Does it snow in Houlton?
Yes. NOAA publishes no 1991-2020 snowfall normal for Houlton's NOAA station; Houlton's own co-op station Houlton (5 mi N) records 96 inches of snow in a normal year.
What is the rainiest month in Houlton?
June, with 4.04 in of precipitation in a normal year; the driest is February with 1.95 in.
What plant hardiness zone is Houlton in?
The USDA's 2023 map puts Houlton in zone 4b in ZIP code 04730, the nearest ZIP area. By the same method at Houlton's NOAA station, the coldest night of a typical year reaches −25°F (30 years, 1991-2020): zone 4a.
How late can frost come in Houlton?
In half of years the last 32°F night comes after May 27; in one year in ten it comes after June 10. Waiting until June 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Houlton in OctoberThis month day by day, its records and recent years
- Maine climateThe statewide normals and every place in the state
- Bridgewater, ME21 miles from this station, 40.5°F a year
- Danforth, ME32 miles from this station, 40.9°F a year
- Patten, ME34 miles from this station, 40.6°F a year
- Presque Isle, ME38 miles from this station, 41.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made