Weather & Climate in St. Marys, PA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
St. Marys has a cool climate with an average annual temperature of 45°F (7°C). Winters average 22°F in January while summers reach 67°F in July. Annual precipitation totals 46.4 inches (wetter than the 38-inch national average). The area receives 66.0 inches of snow annually, making winter weather a significant factor for residents. Air quality is rated Good with a median AQI of 34. 96% of days have good air quality. The city sits at an elevation of 1,713 feet.
Temperature
22°F Jan (-6°C)
67°F Jul (19°C)
| Annual Average | 45.1°F |
| 16% below US avg | |
| January Average | 22°F (-6°C) |
| July Average | 67°F (19°C) |
Geography
| Elevation | 1,713 ft (522 m) |
| Area | 99.5 sq mi (257.8 km²) |
| Population Density | 127/sq mi |
| Coordinates | 41.4550°N, 78.5202°W |
| Timezone | America/New_York |
| County | Elk County County |
| Nearest Airport | Bradford Regional (BFD) 25 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 34.0 |
| Rating | Good |
| Good Days % | 95.8% |
| Unhealthy Days | 0 |
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 45.2 / 100 |
| Social Vulnerability | 29.6 / 100 |
| Community Resilience | 88.5 / 100 |
Hazard Breakdown
| Tornado | Very Low |
| Hurricane | Relatively Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Low |
| Hail | Very Low |
| Strong Wind | Relatively Low |
| Heat Wave | Very Low |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Moderate |
| Ice Storm | Very Low |
| Drought | No Rating |
| Cold Wave | Relatively Low |
| Landslide | Relatively Low |
| Avalanche | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
4 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M3.4.
| Jun 13, 2019 | 9 km N of Blain, Pennsylvania | M3.4 | 143 km | 27 km |
| Feb 3, 2001 | 6 km W of Bath, New York | M3.2 | 136 km | 0 km |
| Mar 15, 2022 | 5 km SSW of Warsaw, New York | M2.6 | 141 km | 5 km |
| Dec 17, 1990 | 5 km SSE of Middleboro, Pennsylvania | M2.5 | 144 km | 5 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
137 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 13 fatalities, 135 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 31, 1985 | EF4 | 47 km | 29.0 mi | 4 |
| May 31, 1985 | EF4 | 92 km | 29.0 mi | 7 |
| May 31, 1985 | EF4 | 33 km | 69.0 mi | 0 |
| Jul 21, 2003 | EF3 | 71 km | 2.5 mi | 0 |
| May 31, 1985 | EF3 | 87 km | 13.0 mi | 0 |
| May 31, 1985 | EF3 | 84 km | 17.0 mi | 0 |
| Sep 3, 1963 | EF3 | 18 km | 8.4 mi | 0 |
| May 15, 1961 | EF3 | 72 km | 3.0 mi | 0 |
| Mar 31, 2022 | EF2 | 100 km | 8.6 mi | 0 |
| Apr 14, 2019 | EF2 | 74 km | 18.0 mi | 0 |
| Oct 2, 2018 | EF2 | 64 km | 4.1 mi | 0 |
| Jul 24, 2010 | EF2 | 89 km | 7.6 mi | 0 |
| Jul 19, 1996 | EF2 | 69 km | 27.4 mi | 0 |
| Jul 19, 1996 | EF2 | 79 km | 10.0 mi | 0 |
| Sep 26, 1994 | EF2 | 84 km | 3.5 mi | 0 |
| Jun 13, 1994 | EF2 | 98 km | 3.0 mi | 0 |
| Sep 23, 1986 | EF2 | 93 km | 0.5 mi | 0 |
| May 31, 1985 | EF2 | 38 km | 19.0 mi | 0 |
| Jun 9, 1980 | EF2 | 90 km | 7.4 mi | 0 |
| Jul 11, 1976 | EF2 | 59 km | 28.7 mi | 1 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Wildfire History
8 wildfires (100+ acres) recorded within 100 km. Largest: BULL RUN (2,003 acres, 2008).
| Year | Name | Acres Burned | Distance |
| 2008 | BULL RUN | 2,003 | 91 km |
| 2009 | WOODRUFF | 757 | 92 km |
| 2018 | FIELDS RUN | 711 | 59 km |
| 2006 | FIVE MILE FIRE | 658 | 55 km |
| 1990 | UNNAMED | 628 | 79 km |
| 2021 | UNNAMED | 586 | 74 km |
| 2006 | OKOME ROAD | 573 | 94 km |
| 2006 | BEAR TRAP | 561 | 62 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 22°F (-6°C) | 3.5 in | Coldest |
| February | 23°F (-5°C) | 2.7 in | Driest |
| March | 32°F (-0°C) | 3.4 in | |
| April | 44°F (7°C) | 4.0 in | |
| May | 55°F (13°C) | 4.3 in | |
| June | 63°F (17°C) | 4.5 in | |
| July | 67°F (19°C) | 4.7 in | Warmest, Wettest |
| August | 66°F (19°C) | 4.3 in | |
| September | 59°F (15°C) | 4.0 in | |
| October | 48°F (9°C) | 3.9 in | |
| November | 37°F (3°C) | 3.8 in | |
| December | 27°F (-3°C) | 3.6 in |
St. Marys has a seasonal temperature swing of 45°F / from 22°F in January to 67°F in July. Total annual precipitation is 46.4 inches, with July being the wettest month (4.7") and February the driest (2.7").