4,902 ft | Twin | 2 routes
As of September 1, 2026
Trail conditions on South Twin Mountain are currently rated Moderate. It's 55°F (feels like 56°F) with SE winds at 4 mph. The shortest of 2 listed routes is Twins and Galehead: 11.5 miles point to point with 3,884 ft of elevation gain, taking about 6-10 hours. South Twin Mountain (4,902 ft) is #8 of 48 on the NH 48 list. See the hour-by-hour South Twin Mountain weather forecast for summit temps, wind chill, and the best hiking window.
South Twin Mountain weather forecast
Hourly summit temps, wind chill & freezing level, trailhead to summit
Feels like 56°F
~3.6°F drop per 1,000ft
Conditions summary as of September 1, 2026
South Twin offers currently favorable conditions with mild temps and light wind, but the higher summits are trending into fog and increasing wind/rain through Wednesday, with heavy rain likely by Wednesday. Trails are largely dry to damp with intermittent mud in the usual low spots between North and South Twin, and slippery wet rock on the steeper sections near the summit. Plan an early start Tuesday or early Wednesday morning to beat deteriorating weather.
Expect temperatures to drop roughly 4-8°F from trailhead to summit with wind increasing from about 10mph at the trailhead to 14-15mph near treeline and summit; add a wind layer once above 4,000ft where trees thin and exposure briefly increases near the top.
Best Hiking Window
Early morning Tuesday through early afternoon, before increasing wind and fog develop; alternatively an early start Wednesday before evening rain arrives
Last synthesized Sep 1, 5:40 PM
Planning a hike here this week?
Trailblazer adds the full 7-day summit forecast, the best day to go for every peak, and conditions for each route up.
Trail: Mt Garfield Trail, Garfield Ridge Trail, Twinway, Bondcliff Trail, spur
Conditions: Dry Trail, Wet Trail, Wet/Slippery Rock, Mud - Minor/Avoidable
“Day 1 of a planned 3 day trip. Garfield Ridge trail is a nice gradual climb, dry low but slippery rocks the higher I got. Final push was not as bad as I remembered, windy cool, socked in for the most part. Found a spot out of the wind for lunch, solo for a while. Planned on staying at the campsite due to rain forecasted. Got an updated forecast from a Nobo while filtering water, no rain until much later! I decided to go to Guyot instead with favorable forecast. Very slow down the waterfall, very wet thru here. Hit East Peak but still can’t find West. Seems like I get into a zone & walk right past it. Water up at hut, not many here, sun was out so I could see what lies ahead. Climb up to South, brutal as always! Love the Twinway, 1 step over and I think a leaner but no issues. Lots of minor mud though. Guyot was busier than I hoped but still had a platform solo.”
Trail: Gale River Trail, Garfield Ridge Trail, Twinway, bushwhack, North Twin Spur, North Twin Trail
Conditions: Dry Trail
“Today was a perfect day to tackle SW Twin. We went in from Gale River and out North Twin with a car spot. Here's how we attacked the bushwhack: -Attempted to follow David Darby's GPS tracks that others have noted. They're not perfect, but they're a great start. https://www.peakbagger.com/climber/ascent.aspx?aid=854365 -Avoided the first entry point that immediately puts you in thick trees and found a much more open one about .1 down the trail -Scott wore yellow tinted eye protection. Somehow it made parts of the bushwhack easier to see. -Hugged the left side of the first set of pines to avoid them. -Kept the southern drop just to our left after them -Fought through the thick stuff going down to the col -Made it to the true summit ok There is no obvious easy way to do this, but if you follow the above it will be less hard.”
Trail: North Twin, Twinway, Garfield Ridge, Gale River
Conditions: Dry Trail, Wet Trail, Wet/Slippery Rock, Standing/Running Water on Trail, Mud - Minor/Avoidable, Mud - Significant
“An OTHH hike, with a smaller than typical group. Two of us started at 7am, and we didn't see anyone else on the North Twin trail until fairly high up, when we were passed easily by a sole hiker traveling light with a small back. The other two of us started later and caught up near the top of N.Twin. We made the 1.3 mile trak over to S.Twin mostly together, and along the way we encountered a number of others doing the out-and-back from S.Twin to bag North. They tagged up on North and beat us back to South, without packs, of course, and aided by being a small fraction of the age of even the youngest (ie. less old) of us. As we made our way down off South to the hut, we encountered the usual trickle of hikers coming up, mostly laden with heavier packs. Two of us dropped packs at the hut and bagged Galehead, while the other two of us took advantage of the opportunity to get a ride back to Haystack Rd by going down from S.Twin this way. The mileage would be about the same, we wouldn't have to regain N.Twin, and we wouldn't have to cross the Little River again. It was a long enough day even without Galehead, and I had been up there enough times already. Boy, does that lower couple of miles of easy walking out on the Gale River Trail go on forever at the end of a day!”
Tap a day header to expand to 3hr or hourly detail
Tuesday Sep 1 | Today Sep 2 | Tomorrow Sep 3 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| AM | PM | night | AM | PM | night | AM | PM | night | |
| Temperature & Wind | |||||||||
| Weather | cloudy | cloudy | ptly cloudy | fog | fog | rain | rain | drizzle | drizzle |
| Temp °F hi / lo | 52° 51° | 52° 51° | 52° 51° | 50° 49° | 51° 49° | 52° 51° | 55° 52° | 56° 55° | 55° 52° |
| Chill °F | — | — | — | 44° | 43° | — | — | — | — |
| Wind mph | 5 | 10 | 13 | 14 | 18 | 47 | 40 | 11 | 19 |
| Gust mph est. | — | 16 | 21 | 22 | 29 | 66 | 56 | 18 | 25 |
| Precipitation | |||||||||
| Precip in (rain/snow) | - | - | - | - | - | 0.9 | 0.6 | - | 0.1 |
| Freezing ft | 12,525 ft | 13,116 ft | 12,927 ft | ||||||
| Conditions | |||||||||
| Cloud cover | 99% | 100% | 61% | 100% | 100% | 100% | 100% | 100% | 100% |
| Vis mi | clear | clear | 8 | <0.1 | <0.1 | <0.1 | 0.3 | 0.9 | 3 |
| UV | 3 | 6 | — | 2 | 5 | — | 0 | 1 | — |
Tap a day header to expand AM/PM/Night detail
| Elevation | Tuesday Sep 1 | Today Sep 2 | Tomorrow Sep 3 |
|---|---|---|---|
| lo/hi °F · wind mph & dir · chill °F | |||
| Summit 4,902 ft | 51/52° 5 | 49/50° 14 | 52/55° 40 |
| 4,100 ft | 53/55° 5 | 51/52° 15 | 53/55° 36 |
| 3,300 ft | 55/57° 5 | 53/53° 15 | 54/55° 30 |
| 2,500 ft | 57/59° 5 | 54/55° 13 | 55/56° 22 |
| Trailhead 2,000 ft | 58/60° 4 | 55/57° 11 | 56/57° 18 |
4 more days of forecast — plan around the weather window, not just tomorrow.
Conditions synthesized from: NWS Higher Summits Forecast, NOAA Open-Meteo, Mount Washington Observatory, NETC Trip Reports, NOHRSC Snow Depth, Mt. Washington Avalanche Center, USGS Stream Levels, OpenWeather Air Quality.
AI-generated from public data. Always verify conditions before heading out — backcountry weather can change quickly.
Part of the Twins Range with excellent views. Galehead Hut is nearby. Often combined with North Twin and Galehead.
Elevation
4,902 ft
Range
Twin
Rank
#8 of 48
Difficulty
Difficult
Coordinates
44.1876, -71.5548
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2 incidents on file · 2 fatal · drawn from NH Fish and Game releases and regional reporting
winter backpacker, identity withheld pending family notification
The body of a winter backpacker was recovered on January 15, 2004 in the area of South Twin Mountain and the Twinway Trail in the White Mountain National Forest. The body was spotted during an Army National Guard helicopter search and airlifted to Concord Hospital. Weather conditions during the week were extremely dangerous, with temperatures dropping to -44°F and wind chills of -94°F on Mt. Washington.
37-year-old male winter backpacker from Athol, Massachusetts
Kenneth Holmes, 37, departed on a solo winter backpacking trip on January 12, 2004 from Lincoln Woods and was reported overdue on January 14. His body was recovered on January 15 near South Twin Mountain at 4,600 feet elevation; the Medical Examiner determined the cause of death was hypothermia due to environmental exposure. Rescue personnel noted behavioral signs consistent with advanced hypothermia, including removal of clothing and erratic movement, during a period of extreme cold with wind chills reported as low as -94°F on Mt. Washington.