Frost dates for Dalecarlia Rsvr, MD
At Dalecarlia Rsvr, the median last spring frost (32°F) is Apr 9 and the median first fall frost is Oct 31, for a typical growing season of 202 days. For a 90% chance that the last frost has passed, wait until Apr 26. Nearby ZIP codes are in USDA hardiness zones 7b to 8a.
- Apr 9Last spring frost (median)50% chance of 32°F after this date
- Apr 26Safer planting date10% chance of 32°F after this date
- Oct 31First fall frost (median)50% chance of 32°F by this date
- 202 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 8 | Apr 23 | May 10 |
| 32°F | Mar 27 | Apr 9 | Apr 26 |
| 28°F | Mar 12 | Mar 30 | Apr 12 |
| 24°F | Feb 27 | Mar 18 | Apr 2 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Oct 7 | Oct 20 | Nov 2 |
| 32°F | Oct 16 | Oct 31 | Nov 13 |
| 28°F | Oct 29 | Nov 9 | Nov 27 |
| 24°F | Nov 5 | Nov 22 | Dec 13 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 157 days | 179 days | 198 days |
| 32°F | 181 days | 202 days | 223 days |
| 28°F | 206 days | 226 days | 248 days |
| 24°F | 226 days | 251 days | 280 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 20016 | 7b | 5 to 10°F | 2 km |
| 20816 | 7b | 5 to 10°F | 2 km |
| 20007 | 7b | 5 to 10°F | 3 km |
| 22207 | 7b | 5 to 10°F | 4 km |
| 20812 | 7b | 5 to 10°F | 4 km |
| 22101 | 7b | 5 to 10°F | 4 km |
| 20057 | 7b | 5 to 10°F | 5 km |
| 20008 | 7b | 5 to 10°F | 5 km |
| 20015 | 7b | 5 to 10°F | 6 km |
| 20818 | 7b | 5 to 10°F | 6 km |
| 20815 | 7b | 5 to 10°F | 6 km |
| 22201 | 7b | 5 to 10°F | 6 km |
| 22209 | 8a | 10 to 15°F | 6 km |
| 20894 | 7b | 5 to 10°F | 6 km |
| 22213 | 7b | 5 to 10°F | 6 km |
| 22205 | 7b | 5 to 10°F | 7 km |
| 20892 | 7b | 5 to 10°F | 7 km |
| 22203 | 7b | 5 to 10°F | 7 km |
| 20817 | 7b | 5 to 10°F | 7 km |
| 20814 | 7b | 5 to 10°F | 7 km |
| 20889 | 7b | 5 to 10°F | 8 km |
| 22046 | 7b | 5 to 10°F | 8 km |
| 20012 | 7b | 5 to 10°F | 8 km |
| 22044 | 7b | 5 to 10°F | 9 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00182325, at 38.9386, -77.1133, elevation 46 m (150 ft).
- Data quality: Representative (10+ years), 24 years of freeze data.
- Average days per year at or below 32°F: 96.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- National Arboretum DC (13 km)
- Rockville 1 NE (18 km)
- Beltsville (19 km)
- Oxon Hill (19 km)
- Laurel 3 W (25 km)
- Glenn Dale Bell Station (27 km)
- Upper Marlboro 3 NNW (31 km)
- Damascus 3 SSW (38 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.