USDA Hardiness Zone 6b
Frost Dates for 02917 — Smithfield, Rhode Island
NOAA 1991–2020 normals from Woonsocket, RI (110 ft), 6 miles north.
Updated
In Smithfield, the last spring frost (32°F) is around April 22 in half of years and has passed by May 6 in nine years out of ten. The first fall frost comes around October 19, as early as October 5 one year in ten, leaving a typical freeze-free season of 179 days (NOAA, Woonsocket, RI).
- Last spring frost
- April 22
- First fall frost
- October 19
- Growing season
- 179 days
- Hardiness zone
- 6b
50% probability
50% probability
freeze-free, 50%
-5 to 0°F (-20.6 to -17.8°C) coldest night
- First snow
- December 6
- Last snow
- March 22
- Winters with snow
- 100%
- Snow per year
- 41.5"
median, 1991–2020
median, 1991–2020
29 of 29 observed
NOAA normal
Frost risk by date in Smithfield
Half of springs at Woonsocket, RI see their last 32°F night by April 22; only one in ten is past it by April 9, and one in ten still has one after May 6. Planting tender crops after April 28 leaves a 30% risk of a frost on them, after May 1 20%, and after May 6 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 50% of the 10 Rhode Island stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 19 in half of years, as early as October 5 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 12 days later, around October 31; in spring the one-in-ten date for 28°F is April 20, 16 days before the 32°F one. The freeze-free season lasts 179 days in a typical year, shorter than at 50% of the 10 Rhode Island stations; it reaches 198 days one year in ten and falls short of 158 one year in ten. On average 129 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 May 5, and return around October 7. Severe cold of 16°F or below comes every winter, usually between December 8 and March 9.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 23 | Apr 27 | Apr 30 | May 2 | May 5 | May 8 | May 11 | May 14 | May 19 |
| 32°F | Apr 9 | Apr 13 | Apr 17 | Apr 19 | Apr 22 | Apr 25 | Apr 28 | May 1 | May 6 |
| 28°F | Mar 28 | Mar 31 | Apr 3 | Apr 4 | Apr 7 | Apr 9 | Apr 12 | Apr 16 | Apr 20 |
| 24°F | Mar 12 | Mar 17 | Mar 22 | Mar 25 | Mar 28 | Mar 31 | Apr 1 | Apr 3 | Apr 7 |
| 20°F | Mar 3 | Mar 8 | Mar 12 | Mar 15 | Mar 17 | Mar 21 | Mar 24 | Mar 27 | Mar 31 |
| 16°F | Feb 21 | Feb 28 | Mar 3 | Mar 6 | Mar 9 | Mar 12 | Mar 14 | Mar 18 | Mar 24 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 26 | Sep 30 | Oct 2 | Oct 4 | Oct 7 | Oct 9 | Oct 12 | Oct 17 | Oct 23 |
| 32°F | Oct 5 | Oct 9 | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 26 | Oct 30 | Nov 2 |
| 28°F | Oct 16 | Oct 20 | Oct 24 | Oct 27 | Oct 31 | Nov 2 | Nov 5 | Nov 9 | Nov 14 |
| 24°F | Oct 29 | Nov 2 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 24 | Nov 29 |
| 20°F | Nov 11 | Nov 16 | Nov 20 | Nov 23 | Nov 27 | Dec 1 | Dec 4 | Dec 8 | Dec 15 |
| 16°F | Nov 23 | Nov 29 | Dec 2 | Dec 5 | Dec 8 | Dec 12 | Dec 16 | Dec 21 | Dec 26 |
Freeze probabilities 1991–2020 at Woonsocket, RI, 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 02917 →Compare Smithfield with another place →
Weather by month in Smithfield
July is the warmest month at Woonsocket, RI, averaging 84°F by day and 63°F at night; January is the coldest at 38°F and 19°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 23% of years.
Warmth for growing adds up to 2,976 growing degree days a year (base 50°F), more than at 70% of the 10 Rhode Island stations. 31% of them (925) have built up by the end of June, and July adds the most, 733. Precipitation totals 52.0 inches a year, most in December (5.3") and least in May (3.6"); May to September bring 38% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 38 | 19 | 4.4 | 100% | 28 | 1 |
| Feb | 40 | 21 | 3.7 | 100% | 26 | 2 |
| Mar | 47 | 28 | 4.9 | 100% | 22 | 15 |
| Apr | 60 | 38 | 4.7 | 99% | 8 | 83 |
| May | 70 | 48 | 3.6 | 23% | <1 | 287 |
| Jun | 79 | 57 | 4.3 | 0% | 0 | 538 |
| Jul | 84 | 63 | 3.6 | 0% | 0 | 733 |
| Aug | 83 | 62 | 4.0 | 0% | 0 | 685 |
| Sep | 75 | 54 | 4.2 | 2% | 0 | 448 |
| Oct | 64 | 42 | 5.1 | 84% | 3 | 149 |
| Nov | 53 | 33 | 4.2 | 100% | 16 | 32 |
| Dec | 43 | 25 | 5.3 | 100% | 25 | 4 |
Monthly normals 1991–2020 at Woonsocket, RI (110 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, N Foster 1 E, RI, 11 miles west of Smithfield and 520 feet higher, has a last frost 3 days later (April 25), the same first-frost date, a season 3 days shorter.
When it snows in Smithfield, Rhode Island
The first measurable snow (0.1 inch or more) in Smithfield usually arrives around December 6, and the last of the season around March 22. Those are the middle dates across the winters of 1991–2020 at Woonsocket, RI, 6.4 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 31 days after the last snow.
Planting calendar for 02917
| When | What to do |
|---|---|
| February 11 – February 25 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 25 – March 11 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 25 – April 8 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 22 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 27 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 5 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 19 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 02917 is 6 miles from Woonsocket, RI, which stands at 110 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 16 other ZIP codes share the station; its figures are presented in full for 02860 (Pawtucket). The 2023 USDA Plant Hardiness Zone Map lists ZIP 02917 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Rhode Island →
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.