USDA Hardiness Zone 9b
Frost Dates for 70058 — Harvey, Louisiana
NOAA 1991–2020 normals from Terrytown 3S, LA (10 ft), 3 miles northeast.
Updated
In Harvey, the last spring frost (32°F) is around February 1 in half of years and has passed by March 6 in nine years out of ten. The first fall frost comes around December 31, as early as December 1 one year in ten, leaving a typical freeze-free season of 330 days (NOAA, Terrytown 3S, LA).
- Last spring frost
- February 1
- First fall frost
- December 31
- Growing season
- 330 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
- 11%
- Snow per year
- 0"
median, 1991–2020
median, 1991–2020
2 of 18 observed
NOAA normal
Frost risk by date in Harvey
Half of springs at Terrytown 3S, LA see their last 32°F night by February 1; only one in ten is past it by January 2, and one in ten still has one after March 6. Planting tender crops after February 16 leaves a 30% risk of a frost on them, after February 27 20%, and after March 6 10%. The 33 days between the even-odds date and the one-in-ten date is wider than at 99% of the 88 Louisiana 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 31 in half of years, as early as December 1 one year in ten, and holds off past January 29 one year in ten. A hard freeze of 28°F follows 8 days later, around January 8; in spring the one-in-ten date for 28°F is February 26, 8 days before the 32°F one. The freeze-free season lasts 330 days in a typical year, longer than at 94% of the 88 Louisiana stations; it reaches 365 days one year in ten and falls short of 291 one year in ten. On average 7 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 21 days longer, to about February 22, and return around December 9. A 24°F night is unusual: 19% of winters had one.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jan 23 | Feb 1 | Feb 7 | Feb 15 | Feb 22 | Feb 28 | Mar 4 | Mar 10 | Mar 16 |
| 32°F90% of yrs | Jan 2 | Jan 13 | Jan 20 | Jan 27 | Feb 1 | Feb 7 | Feb 16 | Feb 27 | Mar 6 |
| 28°F56% of yrs | Dec 29 | Jan 6 | Jan 11 | Jan 17 | Jan 23 | Jan 29 | Feb 2 | Feb 10 | Feb 26 |
| 24°F19% of yrs | too rare for a date | ||||||||
| 20°F4% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 17 | Nov 24 | Dec 1 | Dec 5 | Dec 9 | Dec 15 | Dec 22 | Dec 30 | Jan 7 |
| 32°F90% of yrs | Dec 1 | Dec 10 | Dec 19 | Dec 25 | Dec 31 | Jan 4 | Jan 8 | Jan 15 | Jan 29 |
| 28°F56% of yrs | Dec 20 | Dec 27 | Jan 1 | Jan 4 | Jan 8 | Jan 11 | Jan 18 | Jan 27 | Feb 9 |
| 24°F19% of yrs | too rare for a date | ||||||||
| 20°F4% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Terrytown 3S, LA, 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 70058 →Compare Harvey with another place →
Weather by month in Harvey
July is the warmest month at Terrytown 3S, LA, averaging 92°F by day and 76°F at night; January is the coldest at 63°F and 45°F. From April to November the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 37% of years and March still brings one in 15% of years.
Warmth for growing adds up to 7,565 growing degree days a year (base 50°F), more than at 97% of the 88 Louisiana stations. 43% of them (3,230) have built up by the end of June, and July adds the most, 1,056. Precipitation totals 66.0 inches a year, most in July (7.3") and least in October (3.7"); May to September bring 49% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 63 | 45 | 5.8 | 67% | 4 | 191 |
| Feb | 66 | 49 | 4.0 | 37% | 1 | 234 |
| Mar | 73 | 54 | 5.2 | 15% | <1 | 423 |
| Apr | 78 | 61 | 5.2 | 0% | 0 | 585 |
| May | 85 | 68 | 4.7 | 0% | 0 | 829 |
| Jun | 90 | 75 | 6.9 | 0% | 0 | 967 |
| Jul | 92 | 76 | 7.3 | 0% | 0 | 1056 |
| Aug | 92 | 76 | 6.8 | 0% | 0 | 1055 |
| Sep | 89 | 73 | 6.8 | 0% | 0 | 925 |
| Oct | 81 | 63 | 3.7 | 0% | 0 | 687 |
| Nov | 72 | 53 | 4.2 | 9% | <1 | 375 |
| Dec | 65 | 48 | 5.4 | 42% | 1 | 238 |
Monthly normals 1991–2020 at Terrytown 3S, LA (10 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, New Orleans Audubon, LA, 5 miles northwest of Harvey, has a last frost 8 days earlier (January 24), a first frost 2 days later (January 2), a season 11 days longer.
When it snows in Harvey, Louisiana
Measurable snow is rare here: only 2 of 18 winters from 1991 to 2020 recorded 0.1 inch or more at Terrytown 3S, LA, 3 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 70058
| When | What to do |
|---|---|
| November 23 – December 7 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| December 7 – December 21 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| January 4 – January 18 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| February 1 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by October 8 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by December 17 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| December 31 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 70058 is 3 miles from Terrytown 3S, LA, which stands at 10 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station; its figures are presented in full for 70056 (Gretna). The 2023 USDA Plant Hardiness Zone Map lists ZIP 70058 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.
Frost dates across Louisiana →
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.