USDA Hardiness Zone 8b
Frost Dates for 30274 — Riverdale, Georgia
NOAA 1991–2020 normals from Jonesboro, GA (930 ft), 3 miles southeast.
Updated
In Riverdale, the last spring frost (32°F) is around March 25 in half of years and has passed by April 10 in nine years out of ten. The first fall frost comes around November 12, as early as October 31 one year in ten, leaving a typical freeze-free season of 235 days (NOAA, Jonesboro, GA).
- Last spring frost
- March 25
- First fall frost
- November 12
- Growing season
- 235 days
- Hardiness zone
- 8b
50% probability
50% probability
freeze-free, 50%
15 to 20°F (-9.4 to -6.7°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 39%
- Snow per year
- 0.8"
median, 1991–2020
median, 1991–2020
9 of 23 observed
NOAA normal
Frost risk by date in Riverdale
Half of springs at Jonesboro, GA see their last 32°F night by March 25; only one in ten is past it by March 2, and one in ten still has one after April 10. Planting tender crops after March 31 leaves a 30% risk of a frost on them, after April 4 20%, and after April 10 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 70% of the 127 Georgia stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 12 in half of years, as early as October 31 one year in ten, and holds off past December 2 one year in ten. A hard freeze of 28°F follows 16 days later, around November 28; in spring the one-in-ten date for 28°F is March 29, 12 days before the 32°F one. The freeze-free season lasts 235 days in a typical year, longer than at 50% of the 127 Georgia stations; it reaches 263 days one year in ten and falls short of 211 one year in ten. On average 49 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 12 days longer, to about April 6, and return around November 1. Nights of 24°F, cold enough to damage hardier plants, come in 99% of winters and 16°F in 60%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 20 | Mar 27 | Mar 31 | Apr 3 | Apr 6 | Apr 9 | Apr 12 | Apr 16 | Apr 21 |
| 32°F | Mar 2 | Mar 10 | Mar 16 | Mar 19 | Mar 25 | Mar 28 | Mar 31 | Apr 4 | Apr 10 |
| 28°F | Feb 12 | Feb 22 | Feb 27 | Mar 3 | Mar 8 | Mar 13 | Mar 18 | Mar 24 | Mar 29 |
| 24°F99% of yrs | Jan 22 | Jan 31 | Feb 5 | Feb 11 | Feb 18 | Feb 25 | Mar 1 | Mar 7 | Mar 16 |
| 20°F89% of yrs | Jan 6 | Jan 16 | Jan 22 | Jan 28 | Feb 1 | Feb 5 | Feb 12 | Feb 24 | Mar 4 |
| 16°F60% of yrs | Dec 31 | Jan 8 | Jan 15 | Jan 20 | Jan 25 | Jan 29 | Feb 1 | Feb 8 | Feb 23 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 22 | Oct 26 | Oct 29 | Oct 31 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 16 |
| 32°F | Oct 31 | Nov 2 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 25 | Dec 2 |
| 28°F | Nov 8 | Nov 14 | Nov 18 | Nov 23 | Nov 28 | Dec 1 | Dec 5 | Dec 11 | Dec 22 |
| 24°F99% of yrs | Nov 19 | Nov 28 | Dec 2 | Dec 8 | Dec 15 | Dec 23 | Dec 30 | Jan 4 | Jan 12 |
| 20°F89% of yrs | Dec 5 | Dec 13 | Dec 22 | Dec 29 | Jan 1 | Jan 7 | Jan 12 | Jan 18 | Jan 31 |
| 16°F60% of yrs | Dec 17 | Dec 28 | Jan 1 | Jan 7 | Jan 12 | Jan 16 | Jan 20 | Jan 27 | Feb 5 |
Freeze probabilities 1991–2020 at Jonesboro, GA, 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 30274 →Compare Riverdale with another place →
Weather by month in Riverdale
July is the warmest month at Jonesboro, GA, averaging 90°F by day and 70°F at night; January is the coldest at 53°F and 32°F. A freezing night is all but certain in every month from December to February (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 87% of years and April still brings one in 29% of years.
Warmth for growing adds up to 5,105 growing degree days a year (base 50°F), fewer than at 66% of the 127 Georgia stations. 39% of them (2,015) have built up by the end of June, and July adds the most, 924. Precipitation totals 53.1 inches a year, most in July (5.1") and least in May (3.5"); May to September bring 40% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 53 | 32 | 5.0 | 100% | 17 | 40 |
| Feb | 57 | 35 | 4.9 | 98% | 10 | 53 |
| Mar | 65 | 42 | 5.0 | 87% | 5 | 172 |
| Apr | 73 | 49 | 4.2 | 29% | <1 | 343 |
| May | 81 | 59 | 3.5 | 0% | 0 | 610 |
| Jun | 87 | 67 | 4.6 | 0% | 0 | 798 |
| Jul | 90 | 70 | 5.1 | 0% | 0 | 924 |
| Aug | 89 | 69 | 4.4 | 0% | 0 | 893 |
| Sep | 83 | 63 | 3.6 | 0% | 0 | 697 |
| Oct | 73 | 52 | 3.6 | 12% | <1 | 395 |
| Nov | 62 | 41 | 4.2 | 86% | 5 | 129 |
| Dec | 55 | 35 | 5.0 | 98% | 12 | 52 |
Monthly normals 1991–2020 at Jonesboro, GA (930 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, Atlanta Hartsfield International Airport, GA, 6 miles northwest of Riverdale, has a last frost 10 days earlier (March 15), a first frost 8 days later (November 20), a season 17 days longer.
When it snows in Riverdale, Georgia
Measurable snow is rare here: only 9 of 23 winters from 1991 to 2020 recorded 0.1 inch or more at Jonesboro, GA, 3.2 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 30274
| When | What to do |
|---|---|
| January 14 – January 28 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| January 28 – February 11 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| February 25 – March 11 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| March 25 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 20 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 29 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 12 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 30274 is 3 miles from Jonesboro, GA, which stands at 930 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 9 other ZIP codes share the station; its figures are presented in full for 30281 (Stockbridge). The 2023 USDA Plant Hardiness Zone Map lists ZIP 30274 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°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.