USDA Hardiness Zone 8b
Frost Dates for 36081 — Troy, Alabama
NOAA 1991–2020 normals from Troy, AL (542 ft), 4 miles southwest.
Updated
In Troy, the last spring frost (32°F) is around March 10 in half of years and has passed by March 30 in nine years out of ten. The first fall frost comes around November 21, as early as November 4 one year in ten, leaving a typical freeze-free season of 257 days (NOAA, Troy, AL).
- Last spring frost
- March 10
- First fall frost
- November 21
- Growing season
- 257 days
- Hardiness zone
- 8b
50% probability
50% probability
freeze-free, 50%
15 to 20°F (-9.4 to -6.7°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 10%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
2 of 20 observed
NOAA normal
Frost risk by date in Troy
Half of springs at Troy, AL see their last 32°F night by March 10; only one in ten is past it by February 15, and one in ten still has one after March 30. Planting tender crops after March 18 leaves a 30% risk of a frost on them, after March 23 20%, and after March 30 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 70% of the 115 Alabama stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 21 in half of years, as early as November 4 one year in ten, and holds off past December 14 one year in ten. A hard freeze of 28°F follows 16 days later, around December 7; in spring the one-in-ten date for 28°F is March 17, 13 days before the 32°F one. The freeze-free season lasts 257 days in a typical year, longer than at 86% of the 115 Alabama stations; it reaches 289 days one year in ten and falls short of 228 one year in ten. On average 33 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 14 days longer, to about March 24, and return around November 9. Nights of 24°F, cold enough to damage hardier plants, come in 92% of winters and 16°F in 29%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 2 | Mar 10 | Mar 15 | Mar 19 | Mar 24 | Mar 29 | Apr 2 | Apr 7 | Apr 14 |
| 32°F | Feb 15 | Feb 23 | Mar 1 | Mar 5 | Mar 10 | Mar 14 | Mar 18 | Mar 23 | Mar 30 |
| 28°F99% of yrs | Jan 26 | Feb 4 | Feb 12 | Feb 18 | Feb 24 | Feb 28 | Mar 4 | Mar 10 | Mar 17 |
| 24°F92% of yrs | Jan 4 | Jan 17 | Jan 26 | Jan 31 | Feb 5 | Feb 11 | Feb 18 | Feb 28 | Mar 6 |
| 20°F66% of yrs | Dec 28 | Jan 6 | Jan 13 | Jan 20 | Jan 25 | Jan 31 | Feb 2 | Feb 9 | Feb 24 |
| 16°F29% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 16 | Nov 20 | Nov 29 |
| 32°F | Nov 4 | Nov 8 | Nov 12 | Nov 17 | Nov 21 | Nov 26 | Dec 1 | Dec 5 | Dec 14 |
| 28°F99% of yrs | Nov 13 | Nov 21 | Nov 28 | Dec 1 | Dec 7 | Dec 14 | Dec 21 | Dec 31 | Jan 8 |
| 24°F92% of yrs | Nov 30 | Dec 6 | Dec 16 | Dec 24 | Dec 31 | Jan 4 | Jan 9 | Jan 16 | Jan 29 |
| 20°F66% of yrs | Dec 12 | Dec 26 | Jan 1 | Jan 5 | Jan 9 | Jan 14 | Jan 19 | Jan 28 | Feb 6 |
| 16°F29% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Troy, AL, 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 36081 →Compare Troy with another place →
Weather by month in Troy
July is the warmest month at Troy, AL, averaging 91°F by day and 71°F at night; January is the coldest at 58°F and 37°F. A freezing night is all but certain in every month from December to February (a 90% chance or more). From April to October the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 67% of years.
Warmth for growing adds up to 6,053 growing degree days a year (base 50°F), more than at 74% of the 115 Alabama stations. 41% of them (2,491) have built up by the end of June, and July adds the most, 956. Precipitation totals 52.6 inches a year, most in July (5.3") and least in October (3.3"); May to September bring 43% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 58 | 37 | 4.5 | 97% | 11 | 87 |
| Feb | 63 | 41 | 3.9 | 91% | 7 | 127 |
| Mar | 70 | 46 | 4.8 | 67% | 3 | 278 |
| Apr | 77 | 53 | 4.6 | 9% | <1 | 443 |
| May | 84 | 61 | 3.5 | 0% | 0 | 696 |
| Jun | 89 | 69 | 5.1 | 0% | 0 | 859 |
| Jul | 91 | 71 | 5.3 | 0% | 0 | 956 |
| Aug | 90 | 71 | 4.9 | 0% | 0 | 939 |
| Sep | 87 | 66 | 3.9 | 0% | 0 | 793 |
| Oct | 78 | 56 | 3.3 | 3% | 0 | 525 |
| Nov | 68 | 45 | 3.8 | 67% | 3 | 227 |
| Dec | 61 | 40 | 5.0 | 94% | 9 | 122 |
Monthly normals 1991–2020 at Troy, AL (542 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, Troy 2 W, AL, 6 miles southwest of Troy, has a last frost 7 days later (March 17), a first frost 5 days earlier (November 16), a season 15 days shorter.
When it snows in Troy, Alabama
Measurable snow is rare here: only 2 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Troy, AL, 4.3 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 36081
| When | What to do |
|---|---|
| December 30 – January 13 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| January 13 – January 27 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| February 10 – February 24 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| March 10 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 29 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 7 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 21 onward | Plant 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 36081 is 4 miles from Troy, AL, which stands at 542 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 36081 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.
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.