USDA Hardiness Zone 12b
Frost Dates for 00685 — San Sebastian, Puerto Rico
NOAA 1991–2020 normals from Isabela Substn, PR (420 ft), 10 miles northwest.
Updated
No night at or below 32°F was recorded at Isabela Substn, PR in 1991–2020, not even 36°F, so San Sebastian has no frost dates to plan around; the coolest month, January, averages a low of 67°F.
- Winters with a freeze
- 0%
- Winters with 36°F
- 0%
- Coldest month low
- 67°F
- Hardiness zone
- 12b
32°F or below, 1991–2020
frost possible on leaves
average, January
55 to 60°F (12.8 to 15.6°C) coldest night
Frost risk by date in San Sebastian
Isabela Substn, PR, 10 miles northwest of San Sebastian, did not record a night at or below 32°F in 1991–2020. All 25 other Puerto Rico stations behind this site's ZIP pages recorded no 32°F night either.
Freeze probabilities 1991–2020 at Isabela Substn, PR, 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 00685 →Compare San Sebastian with another place →
Weather by month in San Sebastian
August is the warmest month at Isabela Substn, PR, averaging 87°F by day and 73°F at night; January is the coldest at 81°F and 67°F. Not one month recorded a 32°F night; the lowest monthly average low is 67°F.
Warmth for growing adds up to 9,921 growing degree days a year (base 50°F), fewer than at 76% of the 25 Puerto Rico stations. 47% of them (4,689) have built up by the end of June, and August adds the most, 927. Precipitation totals 64.0 inches a year, most in May (7.2") and least in February (2.5"); May to September bring 49% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 81 | 67 | 3.7 | 0% | 0 | 739 |
| Feb | 81 | 67 | 2.5 | 0% | 0 | 671 |
| Mar | 83 | 67 | 3.9 | 0% | 0 | 770 |
| Apr | 83 | 69 | 4.9 | 0% | 0 | 779 |
| May | 85 | 71 | 7.2 | 0% | 0 | 859 |
| Jun | 86 | 72 | 5.6 | 0% | 0 | 872 |
| Jul | 86 | 73 | 5.0 | 0% | 0 | 910 |
| Aug | 87 | 73 | 6.7 | 0% | 0 | 927 |
| Sep | 87 | 73 | 6.7 | 0% | 0 | 896 |
| Oct | 86 | 72 | 7.0 | 0% | 0 | 899 |
| Nov | 84 | 71 | 6.4 | 0% | 0 | 816 |
| Dec | 82 | 69 | 4.4 | 0% | 0 | 784 |
Monthly normals 1991–2020 at Isabela Substn, PR (420 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, Coloso, PR, 12 miles west of San Sebastian and 380 feet lower, has no 32°F night on record either, and a coolest-month low 1°F colder (66°F).
Where these figures come from
ZIP 00685 is 10 miles from Isabela Substn, PR, which stands at 420 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 00662 (Isabela). The 2023 USDA Plant Hardiness Zone Map lists ZIP 00685 in zone 12b, the band where the coldest night of the year averaged 55 to 60°F (12.8 to 15.6°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Puerto Rico →
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.