Frost Dates for 70460 — Slidell, Louisiana

Half of springs at Slidell Airport, LA see their last 32°F night by March 3; only one in ten is past it by February 4, and one in ten still has one after March 26. Planting tender crops after March 13 leaves a 30% risk of a frost on them, after March 18 20%, and after March 26 10%. The 23 days between the even-odds date and the one-in-ten date is wider than at 52% 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 November 21 in half of years, as early as November 4 one year in ten, and holds off past December 13 one year in ten. A hard freeze of 28°F follows 15 days later, around December 6; in spring the one-in-ten date for 28°F is March 13, 13 days before the 32°F one. The freeze-free season lasts 263 days in a typical year, shorter than at 58% of the 88 Louisiana stations; it reaches 296 days one year in ten and falls short of 236 one year in ten. On average 24 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 17 days longer, to about March 20, and return around November 8. Nights of 24°F, cold enough to damage hardier plants, come in 81% of winters and 16°F in 11%.

July is the warmest month at Slidell Airport, LA, averaging 91°F by day and 73°F at night; January is the coldest at 62°F and 41°F. A freezing night is all but certain in January (a 90% chance or more). From April to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 83% of years and March still brings one in 53% of years.

Warmth for growing adds up to 6,753 growing degree days a year (base 50°F), more than at 61% of the 88 Louisiana stations. 42% of them (2,861) have built up by the end of June, and July adds the most, 995. Precipitation totals 61.9 inches a year, most in July (7.3") and least in October (3.7"); May to September bring 48% of it.

The nearest other station, Slidell, LA, 3 miles southeast of Slidell, has a last frost 7 days earlier (February 24), a first frost 10 days later (December 1), a season 18 days longer.

Measurable snow is rare here: only 0 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Slidell Airport, LA, 3.2 miles away, so there is no typical first-snow date to plan around.

ZIP 70460 is 3 miles from Slidell Airport, LA, which stands at 27 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 70460 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°C) over 1991–2020; a zone describes winter lows, not frost dates.