USDA Hardiness Zone 9b
Frost Dates for 78384 — San Diego, Texas
NOAA 1991–2020 normals from Benavides 2, TX (380 ft), 6 miles south.
Updated
In San Diego, the last spring frost (32°F) is around February 20 in half of years and has passed by March 14 in nine years out of ten. The first fall frost comes around December 1, as early as November 10 one year in ten, leaving a typical freeze-free season of 286 days (NOAA, Benavides 2, TX).
- Last spring frost
- February 20
- First fall frost
- December 1
- Growing season
- 286 days
- Hardiness zone
- 9b
50% probability
50% probability
freeze-free, 50%
25 to 30°F (-3.9 to -1.1°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 8%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
2 of 26 observed
NOAA normal
Frost risk by date in San Diego
Half of springs at Benavides 2, TX see their last 32°F night by February 20; only one in ten is past it by January 18, and one in ten still has one after March 14. Planting tender crops after March 2 leaves a 30% risk of a frost on them, after March 7 20%, and after March 14 10%. The 22 days between the even-odds date and the one-in-ten date is wider than at 63% of the 339 Texas stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.
In fall the first 32°F night comes by December 1 in half of years, as early as November 10 one year in ten, and holds off past January 1 one year in ten. A hard freeze of 28°F follows 17 days later, around December 18; in spring the one-in-ten date for 28°F is March 5, 9 days before the 32°F one. The freeze-free season lasts 286 days in a typical year, longer than at 81% of the 339 Texas stations; it reaches 326 days one year in ten and falls short of 252 one year in ten. On average 15 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 13 days longer, to about March 5, and return around November 18. Nights of 24°F, cold enough to damage hardier plants, come in 53% of winters and 16°F in 3%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Feb 6 | Feb 19 | Feb 25 | Mar 1 | Mar 5 | Mar 8 | Mar 13 | Mar 18 | Mar 28 |
| 32°F99% of yrs | Jan 18 | Jan 27 | Feb 3 | Feb 12 | Feb 20 | Feb 27 | Mar 2 | Mar 7 | Mar 14 |
| 28°F89% of yrs | Dec 19 | Jan 3 | Jan 15 | Jan 22 | Jan 29 | Feb 5 | Feb 16 | Feb 27 | Mar 5 |
| 24°F53% of yrs | Dec 13 | Dec 26 | Jan 3 | Jan 9 | Jan 18 | Jan 26 | Feb 6 | Feb 19 | Mar 3 |
| 20°F16% of yrs | too rare for a date | ||||||||
| 16°F3% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 2 | Nov 6 | Nov 11 | Nov 15 | Nov 18 | Nov 23 | Nov 28 | Dec 3 | Dec 11 |
| 32°F99% of yrs | Nov 10 | Nov 17 | Nov 22 | Nov 26 | Dec 1 | Dec 6 | Dec 12 | Dec 21 | Jan 1 |
| 28°F89% of yrs | Nov 19 | Nov 28 | Dec 5 | Dec 11 | Dec 18 | Dec 25 | Jan 1 | Jan 10 | Jan 27 |
| 24°F53% of yrs | Nov 30 | Dec 10 | Dec 19 | Dec 26 | Jan 1 | Jan 6 | Jan 16 | Feb 1 | Feb 18 |
| 20°F16% of yrs | too rare for a date | ||||||||
| 16°F3% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Benavides 2, TX, 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 78384 →Compare San Diego with another place →
Weather by month in San Diego
August is the warmest month at Benavides 2, TX, averaging 98°F by day and 74°F at night; January is the coldest at 68°F and 43°F. From April to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 57% of years and March still brings one in 35% of years.
Warmth for growing adds up to 8,218 growing degree days a year (base 50°F), more than at 91% of the 351 Texas stations. 45% of them (3,670) have built up by the end of June, and August adds the most, 1,114.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 68 | 43 | 82% | 5 | 235 |
| Feb | 73 | 48 | 57% | 3 | 308 |
| Mar | 77 | 55 | 35% | 1 | 507 |
| Apr | 84 | 62 | 0% | 0 | 684 |
| May | 90 | 69 | 0% | 0 | 916 |
| Jun | 94 | 74 | 0% | 0 | 1020 |
| Jul | 97 | 74 | 0% | 0 | 1097 |
| Aug | 98 | 74 | 0% | 0 | 1114 |
| Sep | 92 | 70 | 0% | 0 | 936 |
| Oct | 86 | 61 | 2% | 0 | 724 |
| Nov | 76 | 52 | 48% | 1 | 432 |
| Dec | 68 | 45 | 78% | 5 | 245 |
Monthly normals 1991–2020 at Benavides 2, TX (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, Alice, TX, 19 miles east of San Diego and 179 feet lower, has a last frost 22 days earlier (January 29), a first frost 28 days later (December 29), a season 51 days longer.
When it snows in San Diego, Texas
Measurable snow is rare here: only 2 of 26 winters from 1991 to 2020 recorded 0.1 inch or more at Benavides 2, TX, 6.3 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 78384
| When | What to do |
|---|---|
| December 12 – December 26 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| December 26 – January 9 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| January 23 – February 6 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| February 20 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by September 8 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 17 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| December 1 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 78384 is 6 miles from Benavides 2, TX, which stands at 380 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 78384 in zone 9b, the band where the coldest night of the year averaged 25 to 30°F (-3.9 to -1.1°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.