Octoraro Lake, Pennsylvania climate: Climate normals at a NOAA weather station
Octoraro Lake's normal year runs from 22°F January nights to 85°F July afternoons, with 48.4 inches of precipitation and 18 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 11.5°C, January lows of −5°C, July highs of 29°C, 1,230 mm of precipitation a year.
- NOAA stationOctoraro Lake
- Station IDUSC00366508
- Location39.80°N 76.04°W
- Elevation260 ft (79 m)
On October 23, the normal high in Octoraro Lake is 62°F and the normal low 41°F, and the chance of measurable rain or snow is 29%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Octoraro Lake.
- Jan 39° 22°
- Feb 42° 23°
- Mar 51° 31°
- Apr 63° 40°
- May 72° 50°
- Jun 80° 60°
- Jul 85° 65°
- Aug 83° 63°
- Sep 76° 56°
- Oct 65° 44°
- Nov 53° 33°
- Dec 43° 27°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Octoraro Lake each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 22°F. The most precipitation falls in September (5.17 in), the least in February (2.86 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 39°F | 22°F | 30.4°F | 3.46 | 5.0 | 11 | <1 | 26 | 9 h 40 min |
| February | 42°F | 23°F | 32.3°F | 2.86 | 7.1 | 10 | <1 | 25 | 10 h 40 min |
| March | 51°F | 31°F | 40.7°F | 4.24 | 2.6 | 11 | <1 | 19 | 11 h 50 min |
| April | 63°F | 40°F | 51.5°F | 3.79 | 0.1 | 11 | <1 | 8 | 13 h 10 min |
| May | 72°F | 50°F | 61.3°F | 3.56 | 0.0 | 12 | 1 | 1 | 14 h 20 min |
| June | 80°F | 60°F | 70.1°F | 4.45 | 0.0 | 11 | 5 | <1 | 15 h |
| July | 85°F | 65°F | 74.8°F | 4.53 | 0.0 | 11 | 9 | <1 | 14 h 40 min |
| August | 83°F | 63°F | 72.9°F | 4.72 | 0.0 | 10 | 6 | <1 | 13 h 50 min |
| September | 76°F | 56°F | 65.8°F | 5.17 | 0.0 | 9 | 1 | <1 | 12 h 30 min |
| October | 65°F | 44°F | 54.2°F | 4.14 | 0.0 | 9 | <1 | 5 | 11 h 10 min |
| November | 53°F | 33°F | 43.1°F | 3.37 | 0.3 | 9 | <1 | 17 | 10 h |
| December | 43°F | 27°F | 34.9°F | 4.13 | 3.0 | 11 | <1 | 25 | 9 h 20 min |
| Year (annual) | 63°F | 43°F | 52.7°F | 48.42 | 18.1 | 124 | 23 | 125 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 4°C | −5°C | −0.9°C | 88 mm | 13 cm |
| February | 5°C | −5°C | 0.2°C | 73 mm | 18 cm |
| March | 10°C | −1°C | 4.8°C | 108 mm | 7 cm |
| April | 17°C | 4°C | 10.8°C | 96 mm | 0 cm |
| May | 22°C | 10°C | 16.3°C | 90 mm | 0 cm |
| June | 27°C | 15°C | 21.2°C | 113 mm | 0 cm |
| July | 29°C | 18°C | 23.8°C | 115 mm | 0 cm |
| August | 28°C | 17°C | 22.7°C | 120 mm | 0 cm |
| September | 24°C | 13°C | 18.8°C | 131 mm | 0 cm |
| October | 18°C | 7°C | 12.3°C | 105 mm | 0 cm |
| November | 12°C | 1°C | 6.2°C | 86 mm | 1 cm |
| December | 6°C | −3°C | 1.6°C | 105 mm | 8 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00366508; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
Which months are mildest at Octoraro Lake?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September has the fewest days with rain (9).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00366508.
When is the last frost at Octoraro Lake?
In Octoraro Lake, the last spring frost (32°F) comes after April 26 in half of years and after May 10 in one year in ten; the first autumn frost comes before October 22 in half of years and before October 9 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 261 year in 10 after May 10; 9 in 10 after April 9
- First autumn frost, half of years before
- October 221 year in 10 before October 9; 9 in 10 before November 3
NOAA puts the median frost-free season at 179 days, and the season without a hard freeze (28°F) at 202 days.
A hard freeze (28°F) comes after April 11 in half of springs and before October 31 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Octoraro Lake in zone 7a in ZIP code 19362, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 7a: the coldest night of a typical year reaches 0°F (28 complete years).
Frost dates for every NOAA station in Pennsylvania · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00366508; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get at Octoraro Lake?
In a normal year in Octoraro Lake, 23 days a year reach 90°F (1 of them 100°F or more), 125 nights fall to 32°F or colder and 124 days bring measurable precipitation.
- Days at 90°F or more
- 23a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 125a normal year
- Days that stay below freezing
- 15high of 32°F or less
- Days with 0.01 inch of precipitation
- 124a normal year
- Days with 1 inch of snow or more
- 5a normal year
The highest temperature in this station's record (since 1978) is 104°F, on August 9, 2001; the lowest is −19°F, on January 22, 1984.
The wettest calendar year on that record is 2018, with 66.72 in; the snowiest season is 2009–10, with 68.4 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00366508; records: ACIS (NOAA Regional Climate Centers), station USC00366508. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Octoraro Lake?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds at Octoraro Lake, 4.0 kWh per square metre a day. July is the sunniest month (82%) and December the cloudiest (67%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 67% | 2.0 |
| February | 69% | 2.9 |
| March | 68% | 3.8 |
| April | 72% | 5.0 |
| May | 72% | 5.5 |
| June | 78% | 6.2 |
| July | 82% | 6.2 |
| August | 80% | 5.4 |
| September | 76% | 4.3 |
| October | 72% | 3.2 |
| November | 73% | 2.3 |
| December | 67% | 1.8 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How many heating and cooling degree days does Octoraro Lake record?
A normal year at Octoraro Lake brings 5,357 heating degree days, 0% fewer than the median U.S. place (5,373), and 897 cooling degree days, 1% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,280 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,073 | 0 |
| February | 916 | 0 |
| March | 753 | 0 |
| April | 413 | 8 |
| May | 166 | 51 |
| June | 24 | 177 |
| July | 1 | 303 |
| August | 5 | 250 |
| September | 73 | 97 |
| October | 347 | 12 |
| November | 657 | 0 |
| December | 932 | 0 |
| Year (annual) | 5,357 | 897 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00366508. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Have recent years at Octoraro Lake been warmer than normal?
2025 averaged 53.1°F, 0.4°F above the 1991-2020 normal of 52.7°F. 4 of the 4 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 53.2°F | +0.5°F | 55.04 | – |
| 2023 | 55.0°F | +2.3°F | 39.93 | 1.9 |
| 2024 | 55.2°F | +2.5°F | 42.71 | 15.8 |
| 2025 | 53.1°F | +0.4°F | 42.08 | 19.5 |
Source: observed years: ACIS, station USC00366508. A year counts only with all twelve months complete.
How does Octoraro Lake's climate compare?
Octoraro Lake is warmer than 91 of the 108 places with their own NOAA record in Pennsylvania, and wetter than 88. Across the 7,247 U.S. stations with normals, its annual mean of 52.7°F is warmer than 52%.
In the Köppen classification computed from these normals, Octoraro Lake is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Octoraro Lake share this climate record?
5 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Oxford, PA5,909 people · 3 mi E
- Perryville, MD4,510 people · 15 mi S
- Rising Sun, MD2,777 people · 7 mi S
- Port Deposit, MD625 people · 13 mi S
- Kirkwood, PA503 people · 4 mi NW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Octoraro Lake's climate
What is the coldest month at Octoraro Lake?
January, with a normal high of 39°F and a normal low of 22°F. The warmest is July (85°F by day, 65°F at night).
Does it snow at Octoraro Lake?
Yes: 18 inches in a normal year, falling on 7 days with 0.1 inch or more, the most in February (7.1 inches).
What is the rainiest month at Octoraro Lake?
September, with 5.17 in of precipitation in a normal year; the driest is February with 2.86 in.
What plant hardiness zone is Octoraro Lake in?
The USDA's 2023 map puts Octoraro Lake in zone 7a in ZIP code 19362, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches 0°F (28 years, 1991-2020): zone 7a.
How late can frost come at Octoraro Lake?
In half of years the last 32°F night comes after April 26; in one year in ten it comes after May 10. Waiting until May 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Pennsylvania climateThe statewide normals and every place in the state
- Conowingo Dam, MD12 miles from this station, 55.4°F a year
- Avondale, PA14 miles from this station, 52.3°F a year
- Coatesville, PA16 miles from this station, 52.8°F a year
- Newark, DE18 miles from this station, 55.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made