USDA Hardiness Zone 13a
Frost Dates for 00690 — San Antonio, Puerto Rico
NOAA 1991–2020 normals from Borinquen Airport, PR (218 ft), 2 miles west.
Updated
No night at or below 32°F was recorded at Borinquen Airport, PR in 1991–2020, not even 36°F, so San Antonio has no frost dates to plan around; the coolest month, February, averages a low of 68°F.
- Winters with a freeze
- 0%
- Winters with 36°F
- 0%
- Coldest month low
- 68°F
- Hardiness zone
- 13a
32°F or below, 1991–2020
frost possible on leaves
average, February
60 to 65°F (15.6 to 18.3°C) coldest night
Frost risk by date in San Antonio
Borinquen Airport, PR, 2 miles west of San Antonio, 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 Borinquen Airport, 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 00690 →Compare San Antonio with another place →
Weather by month in San Antonio
September is the warmest month at Borinquen Airport, PR, averaging 91°F by day and 74°F at night; February is the coldest at 86°F and 68°F. Not one month recorded a 32°F night; the lowest monthly average low is 68°F.
Warmth for growing adds up to 11,062 growing degree days a year (base 50°F), more than at 84% of the 25 Puerto Rico stations. 48% of them (5,278) have built up by the end of June, and August adds the most, 1,014.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 86 | 68 | 0% | 0 | 842 |
| Feb | 86 | 68 | 0% | 0 | 757 |
| Mar | 88 | 69 | 0% | 0 | 870 |
| Apr | 89 | 71 | 0% | 0 | 887 |
| May | 89 | 73 | 0% | 0 | 955 |
| Jun | 91 | 74 | 0% | 0 | 968 |
| Jul | 91 | 74 | 0% | 0 | 1006 |
| Aug | 91 | 74 | 0% | 0 | 1014 |
| Sep | 91 | 74 | 0% | 0 | 981 |
| Oct | 91 | 73 | 0% | 0 | 989 |
| Nov | 89 | 72 | 0% | 0 | 915 |
| Dec | 87 | 70 | 0% | 0 | 880 |
Monthly normals 1991–2020 at Borinquen Airport, PR (218 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, Isabela Substn, PR, 4 miles southeast of San Antonio and 202 feet higher, has no 32°F night on record either, and a coolest-month low 1°F colder (67°F).
Where these figures come from
ZIP 00690 is 2 miles from Borinquen Airport, PR, which stands at 218 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 00603 (Aguadilla). The 2023 USDA Plant Hardiness Zone Map lists ZIP 00690 in zone 13a, the band where the coldest night of the year averaged 60 to 65°F (15.6 to 18.3°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.