Weather & Climate in Grassflat, PA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Grassflat experiences four distinct seasons with an average annual temperature of 46°F (8°C). Winters average 23°F in January while summers reach 68°F in July. Annual precipitation totals 44.5 inches. The area receives 50.3 inches of snow annually, making winter weather a significant factor for residents. The city sits at an elevation of 1,584 feet.
Temperature
23°F Jan (-5°C)
68°F Jul (20°C)
| Annual Average | 46.2°F |
| 14% below US avg | |
| January Average | 23°F (-5°C) |
| July Average | 68°F (20°C) |
Geography
| Elevation | 1,584 ft (483 m) |
| Area | 1.1 sq mi (2.9 km²) |
| Population Density | 369/sq mi |
| Coordinates | 41.0079°N, 78.1087°W |
| Timezone | America/New_York |
| County | Clearfield County County |
| Nearest Airport | State College Regional (SCE) 18 miles away |
Precipitation & Snow
Air Quality
Natural Hazard Risk
| Overall Risk | Relatively Low |
| Risk Score | 67.1 / 100 |
| Social Vulnerability | 62.6 / 100 |
| Community Resilience | 75.4 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Hurricane | Relatively Low |
| Earthquake | Very Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Very Low |
| Strong Wind | Relatively Moderate |
| Heat Wave | Very Low |
| Winter Weather | Relatively High |
| Lightning | Relatively High |
| Ice Storm | Relatively 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
5 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 | 83 km | 27 km |
| Jun 3, 2010 | 4 km ENE of Franklintown, Pennsylvania | M3.1 | 140 km | 2 km |
| Apr 24, 2009 | 1 km S of Franklintown, Pennsylvania | M2.9 | 139 km | 1 km |
| Jun 10, 2025 | 10 km NW of Forksville, Pennsylvania | M2.8 | 135 km | 8 km |
| Oct 25, 2009 | 4 km ENE of Franklintown, Pennsylvania | M2.8 | 139 km | 1 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
148 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 8 fatalities, 112 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 31, 1985 | EF4 | 51 km | 69.0 mi | 0 |
| May 31, 1985 | EF3 | 83 km | 19.0 mi | 6 |
| Jul 29, 1976 | EF3 | 73 km | 25.0 mi | 0 |
| Sep 3, 1963 | EF3 | 69 km | 8.4 mi | 0 |
| Apr 19, 2019 | EF2 | 67 km | 4.9 mi | 0 |
| Oct 2, 2018 | EF2 | 90 km | 4.1 mi | 0 |
| Oct 2, 2018 | EF2 | 98 km | 2.2 mi | 0 |
| May 23, 2011 | EF2 | 87 km | 4.7 mi | 0 |
| Jul 19, 1996 | EF2 | 71 km | 27.4 mi | 0 |
| Jul 19, 1996 | EF2 | 74 km | 6.0 mi | 0 |
| Sep 26, 1994 | EF2 | 55 km | 3.5 mi | 0 |
| Sep 18, 1991 | EF2 | 45 km | 4.0 mi | 0 |
| Nov 20, 1989 | EF2 | 50 km | 3.5 mi | 0 |
| Jun 20, 1989 | EF2 | 88 km | 2.0 mi | 0 |
| May 31, 1985 | EF2 | 94 km | 19.0 mi | 0 |
| Jun 9, 1980 | EF2 | 61 km | 7.4 mi | 0 |
| Apr 9, 1980 | EF2 | 73 km | 0.1 mi | 0 |
| Jul 11, 1976 | EF2 | 98 km | 28.7 mi | 1 |
| Jun 5, 1975 | EF2 | 33 km | 0.1 mi | 0 |
| Aug 16, 1966 | EF2 | 98 km | 4.5 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Wildfire History
6 wildfires (100+ acres) recorded within 100 km. Largest: BULL RUN (2,003 acres, 2008).
| Year | Name | Acres Burned | Distance |
| 2008 | BULL RUN | 2,003 | 83 km |
| 2009 | WOODRUFF | 757 | 99 km |
| 2018 | FIELDS RUN | 711 | 23 km |
| 2006 | FIVE MILE FIRE | 658 | 41 km |
| 2006 | OKOME ROAD | 573 | 74 km |
| 2006 | BEAR TRAP | 561 | 36 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 23°F (-5°C) | 3.2 in | Coldest |
| February | 25°F (-4°C) | 2.6 in | Driest |
| March | 34°F (1°C) | 3.6 in | |
| April | 45°F (7°C) | 3.8 in | |
| May | 55°F (13°C) | 4.1 in | |
| June | 64°F (18°C) | 4.2 in | |
| July | 68°F (20°C) | 4.0 in | Warmest |
| August | 66°F (19°C) | 4.1 in | |
| September | 59°F (15°C) | 4.5 in | Wettest |
| October | 48°F (9°C) | 3.8 in | |
| November | 37°F (3°C) | 3.3 in | |
| December | 29°F (-2°C) | 3.5 in |
Grassflat has a seasonal temperature swing of 44°F / from 23°F in January to 68°F in July. Total annual precipitation is 44.5 inches, with September being the wettest month (4.5") and February the driest (2.6").