USDA Hardiness Zone 7b
Frost Dates for 21643 — Hurlock, Maryland
NOAA 1991–2020 normals from Vienna, MD (10 ft), 11 miles south.
Updated
In Hurlock, the last spring frost (32°F) is around April 8 in half of years and has passed by April 23 in nine years out of ten. The first fall frost comes around November 4, as early as October 22 one year in ten, leaving a typical freeze-free season of 209 days (NOAA, Vienna, MD).
- Last spring frost
- April 8
- First fall frost
- November 4
- Growing season
- 209 days
- Hardiness zone
- 7b
50% probability
50% probability
freeze-free, 50%
5 to 10°F (-15.0 to -12.2°C) coldest night
- First snow
- December 28
- Last snow
- March 2
- Winters with snow
- 100%
- Snow per year
- 14.1"
median, 1991–2020
median, 1991–2020
29 of 29 observed
NOAA normal
Frost risk by date in Hurlock
Half of springs at Vienna, MD see their last 32°F night by April 8; only one in ten is past it by March 24, and one in ten still has one after April 23. Planting tender crops after April 15 leaves a 30% risk of a frost on them, after April 19 20%, and after April 23 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 52% of the 50 Maryland stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 4 in half of years, as early as October 22 one year in ten, and holds off past November 20 one year in ten. A hard freeze of 28°F follows 13 days later, around November 17; in spring the one-in-ten date for 28°F is April 12, 11 days before the 32°F one. The freeze-free season lasts 209 days in a typical year, longer than at 58% of the 50 Maryland stations; it reaches 231 days one year in ten and falls short of 188 one year in ten. On average 83 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 April 21, and return around October 23. Severe cold of 16°F or below comes in 96% of winters, usually between January 2 and February 15.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 6 | Apr 11 | Apr 15 | Apr 18 | Apr 21 | Apr 24 | Apr 27 | May 2 | May 8 |
| 32°F | Mar 24 | Mar 29 | Apr 2 | Apr 5 | Apr 8 | Apr 12 | Apr 15 | Apr 19 | Apr 23 |
| 28°F | Mar 7 | Mar 16 | Mar 19 | Mar 24 | Mar 27 | Mar 31 | Apr 2 | Apr 5 | Apr 12 |
| 24°F | Feb 23 | Feb 28 | Mar 4 | Mar 9 | Mar 13 | Mar 17 | Mar 21 | Mar 27 | Apr 1 |
| 20°F | Feb 8 | Feb 15 | Feb 21 | Feb 25 | Feb 28 | Mar 3 | Mar 7 | Mar 12 | Mar 18 |
| 16°F96% of yrs | Jan 18 | Jan 31 | Feb 4 | Feb 9 | Feb 15 | Feb 21 | Feb 25 | Mar 1 | Mar 7 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 10 | Oct 15 | Oct 18 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 5 |
| 32°F | Oct 22 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 20 |
| 28°F | Nov 2 | Nov 6 | Nov 10 | Nov 13 | Nov 17 | Nov 20 | Nov 24 | Nov 30 | Dec 5 |
| 24°F | Nov 13 | Nov 19 | Nov 25 | Nov 29 | Dec 1 | Dec 5 | Dec 9 | Dec 15 | Dec 22 |
| 20°F | Nov 28 | Dec 3 | Dec 8 | Dec 13 | Dec 17 | Dec 22 | Dec 28 | Jan 2 | Jan 11 |
| 16°F96% of yrs | Dec 10 | Dec 18 | Dec 24 | Dec 29 | Jan 2 | Jan 7 | Jan 12 | Jan 18 | Jan 29 |
Freeze probabilities 1991–2020 at Vienna, MD, 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 21643 →Compare Hurlock with another place →
Weather by month in Hurlock
July is the warmest month at Vienna, MD, averaging 90°F by day and 69°F at night; January is the coldest at 48°F and 28°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 74% of years.
Warmth for growing adds up to 4,375 growing degree days a year (base 50°F), more than at 84% of the 50 Maryland stations. 35% of them (1,537) have built up by the end of June, and July adds the most, 911.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 48 | 28 | 100% | 20 | 13 |
| Feb | 50 | 29 | 100% | 20 | 12 |
| Mar | 58 | 36 | 98% | 12 | 64 |
| Apr | 69 | 44 | 74% | 3 | 229 |
| May | 78 | 54 | 4% | 0 | 492 |
| Jun | 86 | 63 | 0% | 0 | 729 |
| Jul | 90 | 69 | 0% | 0 | 911 |
| Aug | 88 | 67 | 0% | 0 | 848 |
| Sep | 82 | 61 | 0% | 0 | 636 |
| Oct | 72 | 49 | 34% | 1 | 323 |
| Nov | 61 | 39 | 97% | 9 | 100 |
| Dec | 51 | 31 | 100% | 19 | 21 |
Monthly normals 1991–2020 at Vienna, MD (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, Royal Oak 2 SSW, MD, 18 miles west of Hurlock, has a last frost 7 days earlier (April 1), a first frost 3 days later (November 7), a season 11 days longer.
When it snows in Hurlock, Maryland
The first measurable snow (0.1 inch or more) in Hurlock usually arrives around December 28, and the last of the season around March 2. Those are the middle dates across the winters of 1991–2020 at Royal Oak 2 SSW, MD, 18.3 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 37 days after the last snow.
Planting calendar for 21643
| When | What to do |
|---|---|
| January 28 – February 11 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 11 – February 25 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 11 – March 25 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 8 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 12 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 21 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 4 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 21643 is 11 miles from Vienna, MD, which stands at 10 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 21643 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°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.