Lewiston, Maine climate: Normal weather by month, frost dates and records
Lewiston's normal year runs from 12°F January nights to 80°F July afternoons, with 45.2 inches of precipitation and 65 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.9°C, January lows of −11°C, July highs of 27°C, 1,148 mm of precipitation a year.
- NOAA stationLewiston
- Station IDUSC00174566
- Location44.10°N 70.22°W
- Elevation180 ft (55 m)
- From the center2 miles
- Population38,772
On October 23, the normal high in Lewiston is 55°F and the normal low 39°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 Lewiston.
- Jan 28° 12°
- Feb 32° 14°
- Mar 40° 23°
- Apr 53° 35°
- May 65° 46°
- Jun 74° 56°
- Jul 80° 62°
- Aug 79° 60°
- Sep 70° 52°
- Oct 58° 41°
- Nov 45° 31°
- Dec 34° 20°
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 Lewiston each month?
July is the warmest month, with normal highs of 80°F; January the coldest, with normal lows of 12°F. The most precipitation falls in October (4.90 in), the least in May (3.18 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 28°F | 12°F | 20.0°F | 3.28 | 19.4 | 10 | <1 | 30 | 9 h 10 min |
| February | 32°F | 14°F | 22.6°F | 3.24 | 17.3 | 8 | <1 | 26 | 10 h 30 min |
| March | 40°F | 23°F | 31.4°F | 3.53 | 12.3 | 10 | <1 | 25 | 11 h 50 min |
| April | 53°F | 35°F | 43.9°F | 4.04 | 2.9 | 10 | <1 | 10 | 13 h 20 min |
| May | 65°F | 46°F | 55.6°F | 3.18 | 0.0 | 12 | 1 | <1 | 14 h 40 min |
| June | 74°F | 56°F | 64.9°F | 4.28 | 0.0 | 12 | 3 | <1 | 15 h 30 min |
| July | 80°F | 62°F | 70.8°F | 3.51 | 0.0 | 11 | 3 | <1 | 15 h 10 min |
| August | 79°F | 60°F | 69.8°F | 3.36 | 0.0 | 10 | 3 | <1 | 14 h |
| September | 70°F | 52°F | 61.3°F | 3.74 | 0.0 | 9 | 1 | <1 | 12 h 40 min |
| October | 58°F | 41°F | 49.4°F | 4.90 | 0.0 | 9 | <1 | 5 | 11 h 10 min |
| November | 45°F | 31°F | 38.2°F | 3.94 | 1.6 | 9 | <1 | 17 | 9 h 40 min |
| December | 34°F | 20°F | 27.3°F | 4.18 | 11.6 | 11 | <1 | 27 | 8 h 50 min |
| Year (annual) | 55°F | 38°F | 46.3°F | 45.18 | 65.1 | 120 | 11 | 141 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −2°C | −11°C | −6.7°C | 83 mm | 49 cm |
| February | 0°C | −10°C | −5.2°C | 82 mm | 44 cm |
| March | 5°C | −5°C | −0.3°C | 90 mm | 31 cm |
| April | 12°C | 2°C | 6.6°C | 103 mm | 7 cm |
| May | 19°C | 8°C | 13.1°C | 81 mm | 0 cm |
| June | 23°C | 13°C | 18.3°C | 109 mm | 0 cm |
| July | 27°C | 17°C | 21.6°C | 89 mm | 0 cm |
| August | 26°C | 16°C | 21.0°C | 85 mm | 0 cm |
| September | 21°C | 11°C | 16.3°C | 95 mm | 0 cm |
| October | 14°C | 5°C | 9.7°C | 124 mm | 0 cm |
| November | 7°C | 0°C | 3.4°C | 100 mm | 4 cm |
| December | 1°C | −6°C | −2.6°C | 106 mm | 29 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00174566; 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 Lewiston?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September 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 USC00174566.
When is the last frost in Lewiston?
In Lewiston, the last spring frost (32°F) comes after April 25 in half of years and after May 6 in one year in ten; the first autumn frost comes before October 19 in half of years and before October 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
- April 251 year in 10 after May 6; 9 in 10 after April 11
- First autumn frost, half of years before
- October 191 year in 10 before October 5; 9 in 10 before November 3
NOAA puts the median frost-free season at 177 days, and the season without a hard freeze (28°F) at 202 days.
A hard freeze (28°F) comes after April 11 in half of springs and before November 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Lewiston in zone 5b in ZIP code 04240.
Frost dates for every NOAA station in Maine · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00174566; 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 in Lewiston?
In a normal year in Lewiston, 11 days a year reach 90°F, 141 nights fall to 32°F or colder and 120 days bring measurable precipitation.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 141a normal year
- Days that stay below freezing
- 50high of 32°F or less
- Days with 0.01 inch of precipitation
- 120a normal year
- Days with 1 inch of snow or more
- 18a normal year
The highest temperature in this station's record (since 1893) is 102°F, on July 4, 1911; the lowest is −28°F, on January 19, 1925.
The wettest calendar year on that record is 1954, with 61.13 in; the snowiest season is 1970–71, with 144.9 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00174566; records: ACIS (NOAA Regional Climate Centers), station USC00174566. Records use complete months only; a month missing more than three days is left out.
How sunny is Lewiston?
Over a year 69% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Lewiston, 3.6 kWh per square metre a day. September is the sunniest month (76%) and December the cloudiest (60%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 64% | 1.6 |
| February | 67% | 2.5 |
| March | 69% | 3.6 |
| April | 67% | 4.6 |
| May | 66% | 5.2 |
| June | 68% | 5.6 |
| July | 74% | 5.7 |
| August | 76% | 5.2 |
| September | 76% | 4.2 |
| October | 66% | 2.6 |
| November | 64% | 1.7 |
| December | 60% | 1.2 |
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 Lewiston need?
A normal year in Lewiston brings 7,271 heating degree days, 35% more than the median U.S. place (5,373), and 485 cooling degree days, 47% 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 2,366 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,395 | 0 |
| February | 1,186 | 0 |
| March | 1,040 | 0 |
| April | 635 | 0 |
| May | 301 | 11 |
| June | 80 | 79 |
| July | 11 | 192 |
| August | 15 | 164 |
| September | 152 | 39 |
| October | 485 | 1 |
| November | 804 | 0 |
| December | 1,169 | 0 |
| Year (annual) | 7,271 | 485 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00174566. 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 Lewiston's climate compare?
Lewiston is warmer than 36 of the other 41 places with their own NOAA record in Maine, and wetter than 18. Across the 7,247 U.S. stations with normals, its annual mean of 46.3°F is warmer than 25%.
In the Köppen classification computed from these normals, Lewiston 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 Lewiston share this climate record?
3 places have no NOAA station with 1991-2020 normals of their 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.
- Auburn, ME25,200 people · 2 mi SW
- Greene, ME4,492 people · 7 mi NE
- Sabattus, ME5,213 people · 6 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 Lewiston's climate
What is the coldest month in Lewiston?
January, with a normal high of 28°F and a normal low of 12°F. The warmest is July (80°F by day, 62°F at night).
Does it snow in Lewiston?
Yes: 65 inches in a normal year, falling on 23 days with 0.1 inch or more, the most in January (19.4 inches).
What is the rainiest month in Lewiston?
October, with 4.90 in of precipitation in a normal year; the driest is May with 3.18 in.
What plant hardiness zone is Lewiston in?
The USDA's 2023 map puts Lewiston in zone 5b in ZIP code 04240.
How late can frost come in Lewiston?
In half of years the last 32°F night comes after April 25; in one year in ten it comes after May 6. Waiting until May 6 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Maine climateThe statewide normals and every place in the state
- Durham, ME9 miles from this station, 43.9°F a year
- Poland, ME10 miles from this station, 44.1°F a year
- Turner, ME13 miles from this station, 44.8°F a year
- Gray, ME14 miles from this station, 46.3°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made