# Laurel Hill (Pennsylvania)

Laurel Hill, also known as Laurel Ridge or Laurel Mountain, is a 70-mile-long (110 km) mountain that is located in Pennsylvania's Allegheny Mountains. This ridge is flanked by Negro Mountain to its east and Chestnut Ridge to its west. The mountain is home to six state parks: Laurel Ridge State Park, Laurel Mountain State Park, Linn Run State Park, Kooser State Park, Laurel Hill State Park, and Ohiopyle State Park. The 70-mile-long (110 km) Laurel Highlands Hiking Trail runs the length of the ridge.

## History and notable features

In August of 1774, governor of Virginia John Murray, 4th Earl of Dunmore issued the following proclamation: “ ..whereas the Province of Pennsylvania has unduly laid claim to … His Majesty’s territory…. I do hereby in His Majesty’s name require & command all of His Majesty’s subjects West of Laurel Hill to pay a due respect to my Proclamation, strictly prohibiting the authority of Pennsylvania at their peril.”
Two state forests, comprising over 22,000 acres (89 km$^2$), are located on Laurel Hill: Gallitzin State Forest and Forbes State Forest. State Game Lands 42 and 111 are also located on the mountain and also comprise a little over 22,000 acres (89 km$^2$).
Laurel Hill has an average elevation of 2,700 ft (820 m) along its length, while there are individual "knobs" that rise above 2,900 ft (880 m). The highest point is located above the Seven Springs Mountain Resort at 2,994 ft (913 m). Laurel Hill is flanked on its north end by the Conemaugh Gorge and on its south end by the Youghiogheny Gorge, both water gaps being approximately 1,700 ft (520 m) in depth. The ridge continues north of the Conemaugh Gorge for several miles as Rager Mountain, which reaches an elevation of 2,580 feet (790 m). South of the Youghiogheny Gorge, a short ridge, generally still labeled Laurel Hill, at the edge of Ohiopyle State Park, reaches above 2,920 feet (890 m).
The industrial city of Johnstown and historic borough of Ligonier are located near its northern end, while the recreational boroughs of Confluence and Ohiopyle are located towards its southern end. Two major highways cross Laurel Hill, the Pennsylvania Turnpike and U.S. Route 30. The abandoned Laurel Hill Tunnel goes beneath Laurel Hill. A number of smaller state roads cross at other points on the mountain.

## Geology

Laurel Hill is made up of Mississippian and Pennsylvanian clastic sedimentary rocks, consisting mostly of conglomerate, sandstone, and shale. Formations include the Burgoon, Mauch Chunk, Pottsville, and Allegheny. The mountain is anticlinal in structure.
Along the length of this ridge there are several prominent knobs that rise from the ridgeline. They are as follows south to north: Sugarloaf Knob 2,667 ft (813 m), Highpoint 2,994 ft (913 m), Birch Rock Hill 2,934 ft (894 m), Painter Rock Hill 2,920 ft (890 m), Bald Knob 2,930 ft (890 m), Ulery Hill 2,820 ft (860 m), Pea Vine Hill 2,900 ft (880 m), Pikes Peak 2,840 ft (870 m), Mystery Hill 2,880 ft (880 m), and Sugar Camp Hill 2,908 ft (886 m).

## Climate

The Laurel Hill region shares the humid continental climate of the Mid-Atlantic region in which it is located.
The mountain ridge is oriented at right angles to approaching weather systems, forcing prevailing westerly airflows upward. As rising air cools, moisture in the air mass condenses; once reaching the saturation point, precipitation results. Laurel Hill may also act as a barrier to weather systems and slow the movement of storms, which has an impact on the local area and forms a microclimate. Although the mountain is not high enough to create its own weather, its orography is enough to gently nudge weather from hot to warm, cool to cold, and from rain to snow; along with moisture from the Great Lakes, the latter can result in heavy snowfall during winter months. The mountain ridge can be 5 to 10 °F (−15 to −12 °C) cooler than surrounding towns and valleys, depending on other weather variables.
Climate data for Laurel Summit, Pennsylvania, 1991–2020 normals: 2730ft (832m) :
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Mean daily maximum °F (°C) | 30.9 (−0.6) | 33.9 (1.1) | 42.7 (5.9) | 56.1 (13.4) | 64.5 (18.1) | 71.2 (21.8) | 74.5 (23.6) | 73.8 (23.2) | 68.0 (20.0) | 57.7 (14.3) | 45.7 (7.6) | 35.2 (1.8) | 54.5 (12.5) |
| Daily mean °F (°C) | 22.6 (−5.2) | 24.8 (−4.0) | 32.7 (0.4) | 45.1 (7.3) | 54.7 (12.6) | 62.3 (16.8) | 66.4 (19.1) | 65.3 (18.5) | 59.4 (15.2) | 48.4 (9.1) | 37.4 (3.0) | 27.7 (−2.4) | 45.6 (7.5) |
| Mean daily minimum °F (°C) | 14.4 (−9.8) | 15.7 (−9.1) | 22.7 (−5.2) | 34.1 (1.2) | 44.9 (7.2) | 53.4 (11.9) | 58.2 (14.6) | 56.8 (13.8) | 50.7 (10.4) | 39.2 (4.0) | 29.2 (−1.6) | 20.1 (−6.6) | 36.6 (2.6) |
| Average precipitation inches (mm) | 4.41 (112) | 3.50 (89) | 4.72 (120) | 4.87 (124) | 5.47 (139) | 5.94 (151) | 5.14 (131) | 4.78 (121) | 4.81 (122) | 4.23 (107) | 4.31 (109) | 4.43 (113) | 56.61 (1,438) |
| Average snowfall inches (cm) | 38.60 (98.0) | 37.50 (95.3) | 21.50 (54.6) | 6.90 (17.5) | 0.30 (0.76) | 0.00 (0.00) | 0.00 (0.00) | 0.00 (0.00) | 0.00 (0.00) | 2.40 (6.1) | 8.10 (20.6) | 26.90 (68.3) | 142.2 (361.16) |
| Source: NOAA ||||||||||||||
Climate data for Laurel Summit, Pennsylvania (2,600 ft ASL) (1981–2010 normals, extremes 1967–present) :
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F (°C) | 63 (17) | 73 (23) | 75 (24) | 83 (28) | 85 (29) | 85 (29) | 86 (30) | 87 (31) | 89 (32) | 79 (26) | 75 (24) | 68 (20) | 89 (32) |
| Mean daily maximum °F (°C) | 29.7 (−1.3) | 33.9 (1.1) | 42.8 (6.0) | 55.6 (13.1) | 63.2 (17.3) | 70.2 (21.2) | 73.5 (23.1) | 72.7 (22.6) | 66.9 (19.4) | 56.6 (13.7) | 46.1 (7.8) | 34.1 (1.2) | 53.8 (12.1) |
| Daily mean °F (°C) | 22.7 (−5.2) | 25.6 (−3.6) | 33.6 (0.9) | 45.1 (7.3) | 54.1 (12.3) | 62.2 (16.8) | 66.1 (18.9) | 65.3 (18.5) | 58.1 (14.5) | 47.7 (8.7) | 38.0 (3.3) | 27.0 (−2.8) | 45.4 (7.4) |
| Mean daily minimum °F (°C) | 15.7 (−9.1) | 17.3 (−8.2) | 24.3 (−4.3) | 34.6 (1.4) | 44.9 (7.2) | 54.1 (12.3) | 58.7 (14.8) | 57.9 (14.4) | 49.3 (9.6) | 38.8 (3.8) | 29.8 (−1.2) | 19.9 (−6.7) | 37.1 (2.8) |
| Record low °F (°C) | −40 (−40) | −31 (−35) | −22 (−30) | 3 (−16) | 17 (−8) | 27 (−3) | 32 (0) | 30 (−1) | 18 (−8) | 7 (−14) | −10 (−23) | −21 (−29) | −40 (−40) |
| Average precipitation inches (mm) | 4.14 (105) | 3.37 (86) | 4.62 (117) | 4.36 (111) | 5.06 (129) | 4.95 (126) | 4.87 (124) | 4.47 (114) | 4.23 (107) | 3.88 (99) | 4.72 (120) | 4.04 (103) | 52.71 (1,339) |
| Average snowfall inches (cm) | 41.8 (106) | 40.1 (102) | 22.2 (56) | 6.7 (17) | 0.2 (0.51) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 2.5 (6.4) | 9.1 (23) | 29.0 (74) | 151.6 (385) |
| Average precipitation days (≥ 0.01 in) | 23.3 | 24.6 | 16.1 | 15.5 | 14.7 | 12.5 | 10.8 | 10.5 | 9.3 | 12.3 | 18.5 | 24.7 | 192.8 |
| Average snowy days (≥ 0.1 in) | 21.2 | 22.3 | 11.3 | 6.7 | 1.2 | 0 | 0 | 0 | 0 | 1.5 | 8.3 | 20.1 | 92.6 |
| Source: NOAA ||||||||||||||

## Flora and fauna

Laurel Hill has a diversity of habitats, and with that comes a variety of birds and mammals. Ravens and wild turkeys are frequently seen, while the hermit thrush, Canada warbler, brown creeper, and winter wren all nest near the bog at Spruce Flats. During the summer, black-throated blue warblers, blue-headed and red-eyed vireos can be seen. Raptors on the mountain include the broad-winged, red-tailed and red-shouldered hawks, and barred owls.
Commonly seen mammals on the mountain include white-tailed deer, chipmunks, and red and gray squirrels. More elusive animals include the woodchuck, raccoon, and opossum. Black bear have also been seen, but are shy and reclusive and not likely to be encountered.
Snakes including the timber rattlesnake and eastern copperhead also make their home on Laurel Hill around rocks and scree areas.