4,902 ft | Twin | 2 routes
As of September 9, 2026
Trail conditions on South Twin Mountain are currently rated Difficult. It's 40°F (feels like 31°F) with SE winds at 9 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 31°F
Recent Precipitation
Rain: 0.39" (24h) · 0.44" (48h)
~2.4°F drop per 1,000ft
Conditions summary as of September 9, 2026
South Twin will see rain and strong, gusty winds through Wednesday and Thursday, with wind gusts up to 50 mph near the summit and treeline making footing and balance a real challenge despite the minimal exposed area. Trails are already wet and muddy from recent rain, and more moderate rain is expected Wednesday and Thursday, so expect slippery rocks, standing water, and soft ground throughout. Friday offers a notably better window with drier, calmer conditions.
Expect a mild trailhead climate near 60°F giving way to much windier, cooler conditions above treeline, with wind chill dropping to around 37-39°F and gusts up to 50 mph at the summit; layer with a wind-resistant shell for the brief above-treeline summit stretch and be ready to add layers quickly as you exit the trees.
Best Hiking Window
Friday morning, Sept 11, offers the best conditions with lower precip chance (13%) and calmer weather; if hiking sooner, start early Wednesday before afternoon showers intensify
Last synthesized Sep 9, 8:20 AM
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: Frost Trail, Twinway, North Twin Spur
Conditions: Dry Trail, Wet Trail, Wet/Slippery Rock, Standing/Running Water on Trail, Mud - Minor/Avoidable, Mud - Significant
“Out & back from GH hut. Up ST was a challenge, but not as bad as I feared. Descending was definitely a lot slooower for me. Really enjoyed the trip out to NT & back, with a leisurely lunch at the NT outlook waiting out the clouds to clear to enjoy the famous views there & back at ST, which was socked in when we first arrived. Spending 2 nights at the hut really worked for us, giving us all day to travel at a comfortable & companionable pace & wait out the clouds to enjoy the views. And we made it back to the hut for dinner with hours to spare :)”
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.”
Tap a day header to expand to 3hr or hourly detail
Today Sep 9 | Tomorrow Sep 10 | Friday Sep 11 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| AM | PM | night | AM | PM | night | AM | PM | night | |
| Temperature & Wind | |||||||||
| Weather | cloudy | rain | rain | fog | cloudy | cloudy | cloudy | sunny | sunny |
| Temp °F hi / lo | 53° 51° | 55° 52° | 58° 54° | 53° 52° | 51° 43° | 43° 34° | 35° 32° | 43° 37° | 47° 41° |
| Chill °F | — | — | — | — | 31° | 19° | 20° | 27° | 31° |
| Wind mph | 23 | 33 | 52 | 41 | 41 | 40 | 21 | 20 | 23 |
| Gust mph est. | 37 | 53 | 73 | 57 | 57 | 56 | 34 | 32 | 37 |
| Precipitation | |||||||||
| Precip in (rain/snow) | - | 0.1 | 0.9 | - | - | - | - | - | - |
| Freezing ft | 13,059 ft | 13,748 ft | 12,392 ft | ||||||
| Conditions | |||||||||
| Cloud cover | 100% | 100% | 100% | 100% | 53% | 100% | 100% | 5% | 11% |
| Vis mi | clear | 5 | <0.1 | <0.1 | clear | clear | clear | clear | clear |
| UV | 3 | 3 | — | 5 | 6 | — | 5 | 6 | — |
Tap a day header to expand AM/PM/Night detail
| Elevation | Today Sep 9 | Tomorrow Sep 10 | Friday Sep 11 |
|---|---|---|---|
| lo/hi °F · wind mph & dir · chill °F | |||
| Summit 4,902 ft | 51/53° 23 | 52/53° 41 | 32/35° 21 |
| 4,100 ft | 52/53° 19 | 55/56° 37 | 35/39° 16 |
| 3,300 ft | 52/53° 15 | 59/60° 30 | 38/43° 13 |
| 2,500 ft | 53/55° 11 | 62/64° 23 | 40/48° 8 |
| Trailhead 2,000 ft | 54/56° 9 | 64/66° 20 | 41/50° 7 |
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.