Frost Dates for 70461 — Slidell, Louisiana

Half of springs at Slidell, LA see their last 32°F night by February 24; only one in ten is past it by January 29, and one in ten still has one after March 19. Planting tender crops after March 5 leaves a 30% risk of a frost on them, after March 12 20%, and after March 19 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 December 1 in half of years, as early as November 9 one year in ten, and holds off past January 3 one year in ten. A hard freeze of 28°F follows 25 days later, around December 26; in spring the one-in-ten date for 28°F is March 6, 13 days before the 32°F one. The freeze-free season lasts 281 days in a typical year, longer than at 68% of the 88 Louisiana stations; it reaches 319 days one year in ten and falls short of 251 one year in ten. On average 16 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 16 days longer, to about March 12, and return around November 16. Nights of 24°F, cold enough to damage hardier plants, come in 65% of winters and 16°F in 5%.

July is the warmest month at Slidell, LA, averaging 90°F by day and 74°F at night; January is the coldest at 61°F and 42°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 77% of years and March still brings one in 40% of years.

Warmth for growing adds up to 6,722 growing degree days a year (base 50°F), more than at 59% of the 88 Louisiana stations. 42% of them (2,832) have built up by the end of June, and July adds the most, 983. Precipitation totals 66.4 inches a year, most in July (7.7") and least in October (4.2"); May to September bring 48% of it.

The nearest other station, Slidell Airport, LA, 8 miles northwest of Slidell, has a last frost 7 days later (March 3), a first frost 10 days earlier (November 21), a season 18 days shorter.

Measurable snow is rare here: only 1 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Slidell, LA, 2.3 miles away, so there is no typical first-snow date to plan around.

ZIP 70461 is 2 miles from Slidell, LA, which stands at 10 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 70458 (Slidell). The 2023 USDA Plant Hardiness Zone Map lists ZIP 70461 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.