Hurricane Mountain Road (west side)
5886.0 m · net rise 363.7 m · total ascent 406.3 m · overall 6.2% · confidence: good · New Hampshire · share
Shape: stepped — 48% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 254 m.
Not yet matched against documented climbs — the measurement stands on its own.
≈ Overhead cover (tree canopy or structures) spans 31% of this route — detected by comparing the surface model (DSM, treetops and rooftops) against the terrain model (DTM, bare ground). Under cover the bare-ground model is built from fewer laser returns, so metre-scale readings can wobble; maxima whose window sits in a covered zone are marked ≈ below — less certain — the flag does not say whether the true value is higher or lower. Longer windows average over more clean ground and are steadier.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | ≈34% | 3577–3579 m | under overhead cover terrain reads 44.6% at 3010–3012 m across a structure — excluded |
| 3 m (diagnostic) | ≈32% | 4850–4853 m | under overhead cover terrain reads 42.0% at 3010–3013 m across a structure — excluded |
| 5 m | ≈31% | 4850–4855 m | under overhead cover terrain reads 37.9% at 3010–3015 m across a structure — excluded |
| 10 m | 29% | 4846–4856 m | |
| 20 m | 25.1% | 4842–4862 m | |
| 25 m | 23.8% | 4836–4861 m | |
| 50 m | 21.4% | 4826–4876 m | |
| 100 m | 17.9% | 4583–4683 m |
may_continue_beyond_end Extent detection suggests reviewing where this climb starts/ends.
Map
Check this route yourself: Google Maps route via their router · Street View at the base where coverage exists · OSM way 18822718 highlights the mapped road · geojson.io our exact measured line · OpenTopoMap
This climb's data: OCL JSON — the full gradient ladder, quality flags and provenance in the OpenClimb Ladder format.
Measured, not vetted. This page records what the laser record shows about the road's shape — nothing more. Nobody has necessarily ridden or inspected this road for the survey, and a page here is not a recommendation and no guarantee that the road is open, surfaced, rideable or safe. Gates, private sections, missing rights of way and hazards do not show up in elevation data. Check access and conditions on the ground and make your own judgment.
Ridden it, or know better? Submit data for this climb no account needed · Share this climb
© OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap
Profile
Provenance
{
"analysis_version": "0.1.0",
"sample_interval_m": 1.0,
"interpolation": "bilinear",
"smoothing": "none",
"gradient_windows_m": [
5.0,
10.0,
20.0,
25.0,
50.0,
100.0
],
"diagnostic_windows_m": [
2.0,
3.0
],
"elevation_crs": "EPSG:26919",
"elevation_resolution_m": 1.0,
"elevation_tiles": [
"data/cache/usa/nh/USGS_1M_19_x32y489_NH_Umbagog_LiDAR_2016_D16.tif",
"data/cache/usa/nh/USGS_1M_19_x33y489_NH_Umbagog_LiDAR_2016_D16.tif"
],
"calculated_at": "2026-08-22T17:11:21+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"osm_ids": [
18822718,
1005686204
],
"osm_versions": {
"18822718": 20,
"1005686204": 3
},
"osm_timestamps": {
"18822718": "2026-06-19 22:30:51+00:00",
"1005686204": "2025-08-08 14:47:45+00:00"
},
"osm_retrieved_at": "2026-08-22T17:11:21+00:00",
"osm_pbf_path": "data/cache/pbf/new-hampshire-260822.osm.pbf",
"osm_snapshot": "2026-08-21T20:21:11Z",
"elevation_provider": "USGS 3DEP (The National Map)",
"elevation_licence": "Public domain \u2014 USGS 3DEP 1 m DEM, courtesy of the U.S. Geological Survey",
"elevation_dataset": "USGS 3DEP 1 m DEM, NH_Umbagog_LiDAR_2016_D16 (collected 2016)",
"elevation_tile_ids": [
"x32y489",
"x33y489"
],
"route_summit_trim_m": 3730.4,
"route_summit_trim_loss_m": 370.5,
"climb_origin": "named",
"notes": "WEST side from Intervale: same crest-crossing ways as the east entry, direction: reverse + summit_trim isolates the western ascent (added 2026-08-22). mask_ranges_m [3004,3016] (Peter's verdict 2026-08-22): 1.7 m V-notch in the DEM at 3,005-3,015 m \u2014 down -44%/up +44% between flat approaches, the unmapped-culvert signature (Tait's Hill class); the pre-mask 2/3/5 m maxima sat on its climb-out flank. The 23.77% crown wall at 4,836-4,861 m is unrelated and clean.",
"canopy_source": {
"kind": "ept_corridor_max_return",
"ept_source": "https://s3-us-west-2.amazonaws.com/usgs-lidar-public/NH_Umbagog_2016",
"ept_crs": "EPSG:3857",
"station_coverage": 0.996,
"cell_ground_m": 1.0,
"nodes_failed": 0
},
"mask_ranges_m": [
[
3004.0,
3016.0
]
],
"license": "ODbL-1.0",
"license_url": "https://howsteep.org/licensing.html"
}