Summit forecast for 3,340 ft · Sandwich Range · Updated 3x daily
As of July 21, 2026
Middle Sister (3,340 ft) is currently 57°F (feels like 52°F) with overcast and S winds at 9 mph, gusting to 21 mph. Today's freezing level is 13,156–14,173 ft. Expect the summit to run about 5°F colder than the trailhead. Trail conditions are rated Moderate.
Valley forecasts don't apply up high — temperatures drop about 3.0°F per 1,000 ft on Middle Sister.
| Elevation | Temp Range | Max Wind | Wind Chill (Low) |
|---|---|---|---|
| Summit 3,340 ft | 58° – 63°F | 27 mph | 58°F |
| Trailhead 2,000 ft | 61° – 68°F | 20 mph | 61°F |
Freezing level today: 13,156–14,173 ft
~3°F drop per 1,000ft
Tap a day header to expand to 3hr or hourly detail
Today Jul 21 | Tomorrow Jul 22 | Thursday Jul 23 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| AM | PM | night | AM | PM | night | AM | PM | night | |
| Temperature & Wind | |||||||||
| Weather | cloudy | rain | rain | cloudy | ptly cloudy | cloudy | sunny | sunny | sunny |
| Temp °F hi / lo | 59° 58° | 63° 60° | 62° 59° | 62° 60° | 65° 63° | 62° 46° | 51° 46° | 62° 53° | 59° 58° |
| Chill °F | — | — | — | — | — | 38° | 38° | — | — |
| Wind mph | 26 | 27 | 30 | 30 | 27 | 21 | 23 | 21 | 15 |
| Gust mph est. | 42 | 42 | 40 | 45 | 36 | 31 | 27 | — | — |
| Storm risk | — | — | — | mod | mod | — | — | — | — |
| Precipitation | |||||||||
| Precip in (rain/snow) | - | 0.1 | 0.5 | - | - | - | - | - | - |
| Freezing ft | 13,751 ft | 13,261 ft | 9,430 ft | ||||||
| Conditions | |||||||||
| Cloud cover | 100% | 100% | 100% | 100% | 50% | 100% | - | 5% | 5% |
| Vis mi | clear | 4 | <0.1 | 8 | clear | clear | clear | clear | clear |
| UV | 6 | 7 | — | 5 | 7 | — | 6 | 7 | — |
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| Elevation | Today Jul 21 | Tomorrow Jul 22 | Thursday Jul 23 |
|---|---|---|---|
| lo/hi °F · wind mph & dir · chill °F | |||
| Summit 3,340 ft | 58/59° 26 | 60/62° 30 | 46/51° 23 |
| 3,300 ft | 58/59° 26 | 60/62° 30 | 46/51° 23 |
| 2,500 ft | 60/62° 22 | 63/66° 21 | 49/55° 19 |
| Trailhead 2,000 ft | 61/64° 17 | 64/68° 17 | 50/57° 17 |
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.
As of July 21, 2026: Middle Sister (3,340 ft) is currently 57°F (feels like 52°F) with overcast and S winds at 9 mph, gusting to 21 mph. Today's freezing level is 13,156–14,173 ft. Expect the summit to run about 5°F colder than the trailhead. Trail conditions are rated Moderate.
Temperatures drop roughly 3.0°F per 1,000 ft of elevation on Middle Sister. Today the trailhead (2,000 ft) tops out around 68°F while the summit (3,340 ft) reaches about 63°F, with a wind chill as low as 58°F.
Winds at the summit of Middle Sister are forecast to reach 27 mph today. Above treeline there is no shelter from wind — plan layers around wind chill, not air temperature.
Today's freezing level (13,156–14,173 ft) is above the 3,340 ft summit of Middle Sister, so the full route should stay above freezing.