West Thompson Lake, Connecticut climate: Climate normals at a NOAA weather station
West Thompson Lake's normal year runs from 15°F January nights to 82°F July afternoons, with 50.1 inches of precipitation and 39 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.0°C, January lows of −9°C, July highs of 28°C, 1,272 mm of precipitation a year.
- NOAA stationWest Thompson Lake
- Station IDUSC00069388
- Location41.94°N 71.90°W
- Elevation360 ft (110 m)
On October 22, the normal high in West Thompson Lake is 59°F and the normal low 36°F, and the chance of measurable rain or snow is 32%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for West Thompson Lake.
- Jan 35° 15°
- Feb 38° 17°
- Mar 46° 24°
- Apr 58° 34°
- May 69° 45°
- Jun 76° 54°
- Jul 82° 60°
- Aug 80° 58°
- Sep 73° 51°
- Oct 61° 38°
- Nov 50° 30°
- Dec 40° 22°
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 West Thompson Lake each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 15°F. The most precipitation falls in October (4.77 in), the least in May (3.43 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 35°F | 15°F | 24.9°F | 3.78 | 10.6 | 11 | <1 | 29 | 9 h 30 min |
| February | 38°F | 17°F | 27.1°F | 3.53 | 11.6 | 10 | <1 | 27 | 10 h 30 min |
| March | 46°F | 24°F | 34.9°F | 4.45 | 7.2 | 11 | <1 | 26 | 11 h 50 min |
| April | 58°F | 34°F | 46.2°F | 4.57 | 1.5 | 11 | <1 | 14 | 13 h 20 min |
| May | 69°F | 45°F | 56.8°F | 3.43 | 0.0 | 13 | 1 | 2 | 14 h 30 min |
| June | 76°F | 54°F | 65.3°F | 4.48 | 0.0 | 11 | 1 | <1 | 15 h 10 min |
| July | 82°F | 60°F | 71.1°F | 4.02 | 0.0 | 11 | 3 | <1 | 15 h |
| August | 80°F | 58°F | 69.2°F | 4.24 | 0.0 | 10 | 2 | <1 | 14 h |
| September | 73°F | 51°F | 62.0°F | 3.91 | 0.0 | 9 | <1 | <1 | 12 h 30 min |
| October | 61°F | 38°F | 49.9°F | 4.77 | 0.2 | 10 | <1 | 10 | 11 h 10 min |
| November | 50°F | 30°F | 40.2°F | 4.18 | 0.9 | 9 | <1 | 20 | 9 h 50 min |
| December | 40°F | 22°F | 31.0°F | 4.72 | 6.5 | 12 | <1 | 27 | 9 h 10 min |
| Year (annual) | 59°F | 37°F | 48.2°F | 50.08 | 38.5 | 128 | 8 | 156 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 2°C | −9°C | −3.9°C | 96 mm | 27 cm |
| February | 3°C | −9°C | −2.7°C | 90 mm | 29 cm |
| March | 8°C | −4°C | 1.6°C | 113 mm | 18 cm |
| April | 15°C | 1°C | 7.9°C | 116 mm | 4 cm |
| May | 20°C | 7°C | 13.8°C | 87 mm | 0 cm |
| June | 25°C | 12°C | 18.5°C | 114 mm | 0 cm |
| July | 28°C | 16°C | 21.7°C | 102 mm | 0 cm |
| August | 27°C | 15°C | 20.7°C | 108 mm | 0 cm |
| September | 23°C | 10°C | 16.7°C | 99 mm | 0 cm |
| October | 16°C | 4°C | 9.9°C | 121 mm | 1 cm |
| November | 10°C | −1°C | 4.6°C | 106 mm | 2 cm |
| December | 5°C | −6°C | −0.6°C | 120 mm | 17 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00069388; 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 West Thompson Lake?
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 USC00069388.
When is the last frost at West Thompson Lake?
In West Thompson Lake, the last spring frost (32°F) comes after May 1 in half of years and after May 17 in one year in ten; the first autumn frost comes before October 9 in half of years and before September 30 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 11 year in 10 after May 17; 9 in 10 after April 20
- First autumn frost, half of years before
- October 91 year in 10 before September 30; 9 in 10 before October 26
NOAA puts the median frost-free season at 161 days, and the season without a hard freeze (28°F) at 184 days.
A hard freeze (28°F) comes after April 19 in half of springs and before October 21 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts West Thompson Lake in zone 6a in ZIP code 06255, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 6a: the coldest night of a typical year reaches −6°F (16 complete years).
Frost dates for every NOAA station in Connecticut · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00069388; 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 at West Thompson Lake?
In a normal year in West Thompson Lake, 8 days a year reach 90°F, 156 nights fall to 32°F or colder and 128 days bring measurable precipitation.
- Days at 90°F or more
- 8a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 156a normal year
- Days that stay below freezing
- 29high of 32°F or less
- Days with 0.01 inch of precipitation
- 128a normal year
- Days with 1 inch of snow or more
- 12a normal year
The highest temperature in this station's record (since 1962) is 100°F, on July 19, 1982; the lowest is −23°F, on January 22, 1984.
The wettest calendar year on that record is 2018, with 66.28 in; the snowiest season is 1995–96, with 87.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00069388; records: ACIS (NOAA Regional Climate Centers), station USC00069388. Records use complete months only; a month missing more than three days is left out.
How sunny is it at West Thompson Lake?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds at West Thompson Lake, 4.0 kWh per square metre a day. August is the sunniest month (81%) and December the cloudiest (67%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 69% | 1.9 |
| February | 71% | 2.7 |
| March | 71% | 3.8 |
| April | 72% | 5.0 |
| May | 72% | 5.6 |
| June | 76% | 6.1 |
| July | 81% | 6.2 |
| August | 81% | 5.5 |
| September | 79% | 4.5 |
| October | 72% | 3.0 |
| November | 71% | 2.1 |
| December | 67% | 1.6 |
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 West Thompson Lake record?
A normal year at West Thompson Lake brings 6,582 heating degree days, 23% more than the median U.S. place (5,373), and 505 cooling degree days, 44% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,489 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,243 | 0 |
| February | 1,061 | 0 |
| March | 932 | 0 |
| April | 565 | 2 |
| May | 270 | 17 |
| June | 76 | 85 |
| July | 9 | 198 |
| August | 20 | 150 |
| September | 140 | 50 |
| October | 471 | 3 |
| November | 743 | 0 |
| December | 1,054 | 0 |
| Year (annual) | 6,582 | 505 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00069388. 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.
Have recent years at West Thompson Lake been warmer than normal?
2025 averaged 48.3°F, 0.1°F above the 1991-2020 normal of 48.2°F.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2025 | 48.3°F | +0.1°F | 49.42 | 16.0 |
Over 34 complete years from 1968 to 2025, the station's annual mean temperature rose at a fitted 4.9°F per century (+0.27°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00069388; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does West Thompson Lake's climate compare?
West Thompson Lake is warmer than 1 of the 13 places with their own NOAA record in Connecticut, and wetter than 9. Across the 7,247 U.S. stations with normals, its annual mean of 48.2°F is warmer than 33%.
In the Köppen classification computed from these normals, West Thompson Lake 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 West Thompson Lake share this climate record?
7 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.
- Webster, MA17,817 people · 7 mi N
- Pascoag, RI4,081 people · 10 mi E
- East Douglas, MA2,842 people · 13 mi NE
- Chepachet, RI1,819 people · 13 mi E
- Harrisville, RI1,816 people · 12 mi E
- Harmony, RI1,094 people · 15 mi E
- Foster Center, RI328 people · 14 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 West Thompson Lake's climate
What is the coldest month at West Thompson Lake?
January, with a normal high of 35°F and a normal low of 15°F. The warmest is July (82°F by day, 60°F at night).
Does it snow at West Thompson Lake?
Yes: 39 inches in a normal year, falling on 14 days with 0.1 inch or more, the most in February (11.6 inches).
What is the rainiest month at West Thompson Lake?
October, with 4.77 in of precipitation in a normal year; the driest is May with 3.43 in.
What plant hardiness zone is West Thompson Lake in?
The USDA's 2023 map puts West Thompson Lake in zone 6a in ZIP code 06255, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −6°F (16 years, 1991-2020): zone 6a.
How late can frost come at West Thompson Lake?
In half of years the last 32°F night comes after May 1; in one year in ten it comes after May 17. Waiting until May 17 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Connecticut climateThe statewide normals and every place in the state
- North Foster (1 mi E), RI11 miles from this station, 49.1°F a year
- Southbridge, MA12 miles from this station, 48.2°F a year
- Buffumville Lake, MA12 miles from this station, 48.0°F a year
- Hampton, CT14 miles from this station, 48.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made