South Hero, Vermont climate: Normal weather by month, frost dates and records
South Hero's normal year runs from 11°F January nights to 82°F July afternoons, with 35.0 inches of precipitation and 50 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.2°C, January lows of −11°C, July highs of 28°C, 889 mm of precipitation a year.
- NOAA stationSouth Hero
- Station IDUSC00437607
- Location44.63°N 73.30°W
- Elevation110 ft (34 m)
- From the center2 miles
- Population (town)1,727
- Census place183
On October 14, the normal high in South Hero is 59°F and the normal low 43°F, and the chance of measurable rain or snow is 36%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for South Hero.
- Jan 28° 11°
- Feb 31° 12°
- Mar 40° 22°
- Apr 54° 34°
- May 68° 46°
- Jun 77° 56°
- Jul 82° 62°
- Aug 80° 61°
- Sep 72° 53°
- Oct 58° 42°
- Nov 46° 31°
- Dec 34° 21°
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 South Hero each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 11°F. The most precipitation falls in June (4.09 in), the least in February (1.57 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 28°F | 11°F | 19.6°F | 1.94 | 11.4 | 11 | <1 | 30 | 9 h 10 min |
| February | 31°F | 12°F | 21.6°F | 1.57 | 11.6 | 8 | <1 | 26 | 10 h 20 min |
| March | 40°F | 22°F | 30.9°F | 2.02 | 10.6 | 10 | <1 | 26 | 11 h 50 min |
| April | 54°F | 34°F | 43.9°F | 2.66 | 2.2 | 11 | <1 | 13 | 13 h 30 min |
| May | 68°F | 46°F | 57.1°F | 3.36 | 0.0 | 12 | <1 | 1 | 14 h 50 min |
| June | 77°F | 56°F | 66.3°F | 4.09 | 0.0 | 12 | 1 | <1 | 15 h 30 min |
| July | 82°F | 62°F | 71.7°F | 3.85 | 0.0 | 12 | 3 | <1 | 15 h 20 min |
| August | 80°F | 61°F | 70.3°F | 3.62 | 0.0 | 11 | 2 | <1 | 14 h 10 min |
| September | 72°F | 53°F | 62.7°F | 3.26 | 0.0 | 10 | 1 | <1 | 12 h 40 min |
| October | 58°F | 42°F | 50.1°F | 3.74 | 0.1 | 11 | <1 | 3 | 11 h |
| November | 46°F | 31°F | 38.5°F | 2.67 | 3.3 | 10 | <1 | 16 | 9 h 40 min |
| December | 34°F | 21°F | 27.3°F | 2.21 | 10.9 | 11 | <1 | 27 | 8 h 50 min |
| Year (annual) | 56°F | 38°F | 46.7°F | 34.99 | 50.1 | 127 | 6 | 141 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −2°C | −11°C | −6.9°C | 49 mm | 29 cm |
| February | −1°C | −11°C | −5.8°C | 40 mm | 29 cm |
| March | 5°C | −6°C | −0.6°C | 51 mm | 27 cm |
| April | 12°C | 1°C | 6.6°C | 68 mm | 6 cm |
| May | 20°C | 8°C | 13.9°C | 85 mm | 0 cm |
| June | 25°C | 13°C | 19.1°C | 104 mm | 0 cm |
| July | 28°C | 17°C | 22.1°C | 98 mm | 0 cm |
| August | 27°C | 16°C | 21.3°C | 92 mm | 0 cm |
| September | 22°C | 12°C | 17.1°C | 83 mm | 0 cm |
| October | 14°C | 6°C | 10.1°C | 95 mm | 0 cm |
| November | 8°C | 0°C | 3.6°C | 68 mm | 8 cm |
| December | 1°C | −6°C | −2.6°C | 56 mm | 28 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00437607; 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 South Hero?
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 (10).
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 USC00437607.
When is the last frost in South Hero?
In South Hero, the last spring frost (32°F) comes after April 28 in half of years and after May 10 in one year in ten; the first autumn frost comes before October 20 in half of years and before October 4 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 281 year in 10 after May 10; 9 in 10 after April 19
- First autumn frost, half of years before
- October 201 year in 10 before October 4; 9 in 10 before November 2
NOAA puts the median frost-free season at 174 days, and the season without a hard freeze (28°F) at 197 days.
A hard freeze (28°F) comes after April 18 in half of springs and before November 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts South Hero in zone 5b in ZIP code 05486, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, South Hero's NOAA station is in zone 5b: the coldest night of a typical year reaches −14°F (24 complete years).
Frost dates for every NOAA station in Vermont · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00437607; 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 South Hero?
In a normal year in South Hero, 6 days a year reach 90°F, 141 nights fall to 32°F or colder and 127 days bring measurable precipitation.
- Days at 90°F or more
- 6a 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
- 59high of 32°F or less
- Days with 0.01 inch of precipitation
- 127a normal year
- Days with 1 inch of snow or more
- 14a normal year
The highest temperature in this station's record (since 1969) is 99°F, on August 1, 1975; the lowest is −31°F, on January 27, 1994.
The wettest calendar year on that record is 1996, with 42.08 in; the snowiest season is 1970–71, with 90.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00437607; records: ACIS (NOAA Regional Climate Centers), station USC00437607. Records use complete months only; a month missing more than three days is left out.
How sunny is South Hero?
Over a year 68% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around South Hero, 3.5 kWh per square metre a day. August is the sunniest month (75%) and December the cloudiest (54%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 60% | 1.5 |
| February | 62% | 2.3 |
| March | 65% | 3.4 |
| April | 66% | 4.5 |
| May | 67% | 5.2 |
| June | 69% | 5.6 |
| July | 74% | 5.7 |
| August | 75% | 5.1 |
| September | 75% | 4.0 |
| October | 62% | 2.4 |
| November | 60% | 1.6 |
| December | 54% | 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 South Hero need?
A normal year in South Hero brings 7,220 heating degree days, 34% more than the median U.S. place (5,373), and 577 cooling degree days, 36% 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 2,576 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,409 | 0 |
| February | 1,217 | 0 |
| March | 1,057 | 0 |
| April | 632 | 1 |
| May | 264 | 21 |
| June | 59 | 99 |
| July | 7 | 214 |
| August | 15 | 181 |
| September | 129 | 59 |
| October | 466 | 2 |
| November | 795 | 0 |
| December | 1,170 | 0 |
| Year (annual) | 7,220 | 577 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00437607. 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 South Hero been warmer than normal lately?
Over 43 complete years from 1970 to 2019, the station's annual mean temperature rose at a fitted 4.2°F per century (+0.23°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 South Hero's climate compare?
South Hero is warmer than 26 of the other 28 places with their own NOAA record in Vermont, and wetter than 0. Across the 7,247 U.S. stations with normals, its annual mean of 46.7°F is warmer than 26%.
In the Köppen classification computed from these normals, South Hero is Dfa: continental, 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 South Hero share this climate record?
5 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.
- Keeseville, NY2,572 people · 12 mi SW
- Morrisonville, NY1,688 people · 13 mi W
- Cumberland Head, NY1,622 people · 8 mi NW
- Plattsburgh West, NY1,306 people · 11 mi W
- Parc, NY126 people · 8 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.
Questions about South Hero's climate
What is the coldest month in South Hero?
January, with a normal high of 28°F and a normal low of 11°F. The warmest is July (82°F by day, 62°F at night).
Does it snow in South Hero?
Yes: 50 inches in a normal year, falling on 32 days with 0.1 inch or more, the most in February (11.6 inches).
What is the rainiest month in South Hero?
June, with 4.09 in of precipitation in a normal year; the driest is February with 1.57 in.
What plant hardiness zone is South Hero in?
The USDA's 2023 map puts South Hero in zone 5b in ZIP code 05486, the nearest ZIP area. By the same method at South Hero's NOAA station, the coldest night of a typical year reaches −14°F (24 years, 1991-2020): zone 5b.
How late can frost come in South Hero?
In half of years the last 32°F night comes after April 28; in one year in ten it comes after May 10. Waiting until May 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Vermont climateThe statewide normals and every place in the state
- Plattsburgh, NY8 miles from this station, 45.3°F a year
- Essex Junction, VT12 miles from this station, 46.4°F a year
- Burlington, VT13 miles from this station, 47.6°F a year
- Peru, NY14 miles from this station, 46.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made