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Weather & Climate in Rosslyn Farms, PA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Rosslyn Farms experiences four distinct seasons with an average annual temperature of 52°F (11°C). Winters average 29°F in January while summers reach 73°F in July. The area gets 275 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Annual precipitation totals 39.6 inches. The area receives 44.1 inches of snow annually, making winter weather a significant factor for residents. Air quality is rated Good with a median AQI of 40. The city sits at an elevation of 1,021 feet.
Temperature
29°F Jan (-2°C)
73°F Jul (23°C)
| Annual Average | 51.8°F |
| 4% below US avg | |
| January Average | 29°F (-2°C) |
| July Average | 73°F (23°C) |
| Sunny Days | 275 days/yr |
Geography
| Elevation | 1,021 ft (311 m) |
| Area | 0.2 sq mi (0.6 km²) |
| Population Density | 923/sq mi |
| Coordinates | 40.4224°N, 80.0885°W |
| Timezone | America/New_York |
| County | Washington County County |
| Nearest Airport | Pittsburgh International (PIT) 9 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 40.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively Moderate |
| Risk Score | 83.1 / 100 |
| Social Vulnerability | 22.7 / 100 |
| Community Resilience | 87.3 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Relatively Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Relatively Moderate |
| Strong Wind | Relatively Low |
| Heat Wave | Relatively Low |
| Winter Weather | Very Low |
| Lightning | Relatively High |
| Ice Storm | Relatively Low |
| Drought | Relatively Low |
| Cold Wave | Very Low |
| Landslide | Relatively Moderate |
| Avalanche | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
12 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M4.5.
| Sep 25, 1998 | 2 km SW of Adamsville, Pennsylvania | M4.5 | 122 km | 5 km |
| Mar 12, 2007 | Ohio | M3.7 | 145 km | 5 km |
| Jun 3, 2017 | 1 km WNW of Batesville, Ohio | M3.4 | 117 km | 2 km |
| Apr 24, 2025 | 3 km S of Pleasant City, Ohio | M3.1 | 138 km | 6 km |
| Apr 22, 2025 | 3 km ESE of Buffalo, Ohio | M3.1 | 132 km | 5 km |
| Apr 2, 2017 | 5 km W of Graysville, Ohio | M3.0 | 130 km | 4 km |
| Mar 30, 2024 | 2 km SSW of Maple Ridge, Ohio | M3.0 | 97 km | 6 km |
| May 9, 2025 | 3 km S of Pleasant City, Ohio | M2.9 | 138 km | 5 km |
| Aug 7, 2000 | 2 km S of Limaville, Ohio | M2.9 | 108 km | 5 km |
| Apr 29, 2025 | 1 km SE of Pleasant City, Ohio | M2.8 | 136 km | 2 km |
| Sep 4, 2011 | 3 km N of Saint Marys, West Virginia | M2.6 | 146 km | 5 km |
| Sep 11, 2024 | 4 km WNW of Claysville, Pennsylvania | M2.5 | 45 km | 4 km |
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Tornado History
298 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 19 fatalities, 600 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Jun 2, 1998 | EF4 | 85 km | 36.5 mi | 0 |
| Jun 3, 1980 | EF4 | 40 km | 11.8 mi | 0 |
| May 31, 1985 | EF3 | 55 km | 39.0 mi | 9 |
| Oct 12, 1978 | EF3 | 82 km | 7.3 mi | 0 |
| Jul 11, 1976 | EF3 | 51 km | 11.8 mi | 1 |
| May 8, 1969 | EF3 | 95 km | 2.0 mi | 1 |
| Aug 3, 1963 | EF3 | 21 km | 0.1 mi | 2 |
| Aug 5, 1956 | EF3 | 96 km | 0.1 mi | 2 |
| Jun 26, 2024 | EF2 | 36 km | 10.8 mi | 0 |
| May 11, 2024 | EF2 | 17 km | 5.8 mi | 0 |
| May 7, 2024 | EF2 | 63 km | 15.3 mi | 0 |
| Aug 25, 2023 | EF2 | 74 km | 2.0 mi | 0 |
| Aug 1, 2022 | EF2 | 58 km | 1.8 mi | 0 |
| Mar 31, 2022 | EF2 | 76 km | 8.6 mi | 0 |
| Oct 21, 2021 | EF2 | 42 km | 15.7 mi | 0 |
| Jul 29, 2021 | EF2 | 80 km | 6.2 mi | 0 |
| Jul 29, 2021 | EF2 | 82 km | 2.7 mi | 0 |
| Oct 2, 2018 | EF2 | 66 km | 1.6 mi | 0 |
| Mar 23, 2011 | EF2 | 34 km | 9.0 mi | 0 |
| Nov 10, 2002 | EF2 | 98 km | 7.0 mi | 1 |
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 29°F (-2°C) | 2.5 in | Coldest |
| February | 31°F (-0°C) | 2.3 in | Driest |
| March | 40°F (4°C) | 3.2 in | |
| April | 50°F (10°C) | 3.2 in | |
| May | 61°F (16°C) | 3.9 in | Wettest |
| June | 69°F (21°C) | 3.9 in | |
| July | 73°F (23°C) | 3.9 in | Warmest |
| August | 72°F (22°C) | 3.5 in | |
| September | 65°F (18°C) | 3.2 in | |
| October | 53°F (12°C) | 2.5 in | |
| November | 43°F (6°C) | 3.0 in | |
| December | 33°F (1°C) | 2.8 in |
Rosslyn Farms has a seasonal temperature swing of 44°F / from 29°F in January to 73°F in July. Total annual precipitation is 37.9 inches, with May being the wettest month (3.9") and February the driest (2.3").