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USDA Hardiness Zone 5a

Frost Dates for 05459 — Highgate Center, Vermont

NOAA 1991–2020 normals from St Albans Radio, VT (380 ft), 6 miles southwest.

Updated

In Highgate Center, the last spring frost (32°F) is around May 1 in half of years and has passed by May 16 in nine years out of ten. The first fall frost comes around October 12, as early as September 28 one year in ten, leaving a typical freeze-free season of 161 days (NOAA, St Albans Radio, VT).

Last spring frost
May 1

50% probability

First fall frost
October 12

50% probability

Growing season
161 days

freeze-free, 50%

Hardiness zone
5a

-20 to -15°F (-28.9 to -26.1°C) coldest night

First snow
October 31

median, 1991–2020

Last snow
April 14

median, 1991–2020

Winters with snow
100%

17 of 17 observed

Snow per year
79.9"

NOAA normal

Frost risk by date in Highgate Center

Half of springs at St Albans Radio, VT see their last 32°F night by May 1; only one in ten is past it by April 20, and one in ten still has one after May 16. Planting tender crops after May 7 leaves a 30% risk of a frost on them, after May 10 20%, and after May 16 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 24% of the 41 Vermont stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 12 in half of years, as early as September 28 one year in ten, and holds off past October 26 one year in ten. A hard freeze of 28°F follows 11 days later, around October 23; in spring the one-in-ten date for 28°F is May 5, 11 days before the 32°F one. The freeze-free season lasts 161 days in a typical year, longer than at 83% of the 41 Vermont stations; it reaches 181 days one year in ten and falls short of 142 one year in ten. On average 148 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about May 12, and return around October 2. Severe cold of 16°F or below comes every winter, usually between November 24 and March 30.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 29May 3May 7May 10May 12May 15May 19May 22May 26
32°FApr 20Apr 24Apr 26Apr 29May 1May 4May 7May 10May 16
28°FApr 9Apr 14Apr 17Apr 19Apr 21Apr 24Apr 27Apr 30May 5
24°FApr 2Apr 5Apr 7Apr 9Apr 11Apr 14Apr 16Apr 19Apr 23
20°FMar 22Mar 29Mar 31Apr 2Apr 4Apr 5Apr 7Apr 10Apr 15
16°FMar 15Mar 19Mar 23Mar 26Mar 30Apr 1Apr 2Apr 5Apr 8
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FSep 18Sep 24Sep 27Sep 30Oct 2Oct 4Oct 7Oct 10Oct 15
32°FSep 28Oct 2Oct 6Oct 9Oct 12Oct 15Oct 18Oct 21Oct 26
28°FOct 6Oct 12Oct 16Oct 20Oct 23Oct 27Oct 30Nov 1Nov 6
24°FOct 17Oct 25Oct 29Nov 1Nov 3Nov 6Nov 9Nov 13Nov 19
20°FOct 31Nov 4Nov 7Nov 11Nov 14Nov 17Nov 21Nov 25Nov 30
16°FNov 8Nov 13Nov 17Nov 21Nov 24Nov 26Nov 29Dec 2Dec 7

Freeze probabilities 1991–2020 at St Albans Radio, VT, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.

Frost risk on any date in 05459 →Compare Highgate Center with another place →

Weather by month in Highgate Center

July is the warmest month at St Albans Radio, VT, averaging 79°F by day and 61°F at night; January is the coldest at 25°F and 8°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 53% of years.

Warmth for growing adds up to 2,304 growing degree days a year (base 50°F), more than at 68% of the 41 Vermont stations. 31% of them (710) have built up by the end of June, and July adds the most, 625. Precipitation totals 38.2 inches a year, most in June (4.1") and least in February (1.9"); May to September bring 50% of it.

Monthly normals 1991–2020 at St Albans Radio, VT
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan2582.1100%291
Feb29101.9100%260
Mar37202.6100%272
Apr52333.2100%1336
May66463.253%1217
Jun74564.10%0454
Jul79614.10%0625
Aug77593.70%0560
Sep69513.915%1316
Oct56403.995%783
Nov44302.9100%1710
Dec32182.6100%271

Monthly normals 1991–2020 at St Albans Radio, VT (380 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.

Compared with the next station

The nearest other station, Enosburg Falls, VT, 11 miles east of Highgate Center, has a last frost 13 days later (May 14), a first frost 11 days earlier (October 1), a season 22 days shorter.

Frost dates for 05450 (Enosburg Falls) →

When it snows in Highgate Center, Vermont

The first measurable snow (0.1 inch or more) in Highgate Center usually arrives around October 31, and the last of the season around April 14. Those are the middle dates across the winters of 1991–2020 at St Albans Radio, VT, 6.4 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 17 days after the last snow.

Planting calendar for 05459

What to do and when, from the 50% frost dates for Highgate Center, Vermont
WhenWhat to do
February 20 – March 6Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 6 – March 20Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 3 – April 17Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 1 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 20Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 28Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 12 onwardPlant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter.

The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.

Where these figures come from

ZIP 05459 is 6 miles from St Albans Radio, VT, which stands at 380 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 05478 (Saint Albans). The 2023 USDA Plant Hardiness Zone Map lists ZIP 05459 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Vermont →

Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.

Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.

ZIP codes measured at the same station

Other zone 5a places in Vermont