New Hampshire mountains

Smarts Mountain mountain forecast

3,238 ft (987 m) · prominence 2,182 ft (665 m) · New Hampshire

At the summit’s height the GFS model has 55°F and wind from the ENE at 16 mph, Sat, Sep 26, 2:00 AM EDT. The freezing level is at 12,953 ft, above the summit. The National Weather Service forecast for saturday: mostly cloudy then chance light rain, high 58°F at its grid elevation of 2,477 ft.

Live map with slope anglesLyme forecast

The summit on the map

Smarts Mountain and the summits and ski areas around it. Each has its own page.

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Now

Summit
3,238 ft (987 m)
Forecast grid ground
2,477 ft (755 m)
Summit temperature
55°F
Summit wind
ENE 16 mph
Freezing level
12,953 ft
High at the summit, by lapse rate
55°F

The last tile carries the Weather Service’s high from its grid’s 2,477 ft up 761 ft to the summit at the standard atmosphere’s 6.5 °C per kilometer (about 3.6 °F per 1,000 ft). Real lapse rates vary: an inversion can make the summit warmer than the valley.

At the summit’s height

Temperature, wind and wind chill up there, and the freezing level, every six hours for three days.

TimeTempWindWind chillFreezing level
Sat, Sep 26, 2:00 AM EDT55°FENE 16 mph12,953 ft9,715 ft above the summit
Sat, Sep 26, 8:00 AM EDT50°FENE 17 mph44°F13,360 ft10,121 ft above the summit
Sat, Sep 26, 2:00 PM EDT54°FNE 19 mph12,559 ft9,321 ft above the summit
Sat, Sep 26, 8:00 PM EDT50°FENE 25 mph43°F12,884 ft9,646 ft above the summit
Sun, Sep 27, 2:00 AM EDT48°FENE 27 mph40°F12,503 ft9,265 ft above the summit
Sun, Sep 27, 8:00 AM EDT49°FENE 29 mph41°F12,621 ft9,383 ft above the summit
Sun, Sep 27, 2:00 PM EDT51°FE 27 mph12,687 ft9,449 ft above the summit
Sun, Sep 27, 8:00 PM EDT50°FE 25 mph12,185 ft8,947 ft above the summit
Mon, Sep 28, 2:00 AM EDT51°FE 22 mph11,906 ft8,668 ft above the summit
Mon, Sep 28, 8:00 AM EDT49°FE 19 mph42°F11,909 ft8,671 ft above the summit
Mon, Sep 28, 2:00 PM EDT49°FE 15 mph43°F11,709 ft8,471 ft above the summit
Mon, Sep 28, 8:00 PM EDT48°FENE 13 mph42°F11,503 ft8,264 ft above the summit

NOAA’s GFS model, run Fri, Sep 25, 8:00 PM EDT, interpolated to 3,238 ft between its pressure levels: the free air over the summit, which on a ridge is close to what a climber feels and in a sheltered spot is more than it. Wind chill is the National Weather Service’s formula, given where the temperature is 50°F or less and the wind above 3 mph.

The National Weather Service forecast at the summit

PeriodTempWindForecast
OvernightLow 47°FNE 10 mphMostly cloudy, with a low around 47. Northeast wind around 10 mph, with gusts as high as 25 mph.
SaturdayHigh 58°FNE 10 mphA chance of rain after 2pm. Mostly cloudy, with a high near 58. Northeast wind around 10 mph, with gusts as high as 25 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.
Saturday NightLow 48°FNE 10-15 mphRain. Cloudy, with a low around 48. Northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch possible.
SundayHigh 52°FE 15 mphRain likely. Mostly cloudy, with a high near 52. East wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 60%.
Sunday NightLow 48°FE 15 mphRain likely. Mostly cloudy, with a low around 48. East wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 60%.
MondayHigh 51°FNE 5-10 mphRain. Cloudy, with a high near 51. Chance of precipitation is 90%.
Monday NightLow 48°FNE 5 mphRain. Cloudy, with a low around 48. Chance of precipitation is 80%.
TuesdayHigh 55°FNW 5 mphA chance of rain before 8am. Mostly cloudy, with a high near 55. Chance of precipitation is 30%.
Tuesday NightLow 48°FNW 0-5 mphMostly cloudy, with a low around 48.
WednesdayHigh 61°FW 0-5 mphPartly sunny, with a high near 61.

The Weather Service’s forecast asked at the summit’s coordinates (43.8257, -72.0387), by its office in Gray - Portland, ME. Its grid cell is 2.5 km across and sits at 2,477 ft (755 m), 761 ft below the summit, so its temperatures and winds are for that height.

Cloud base and the summit

TimeSkyTemp and dew pointCloud base
Sat, Sep 26, 8:00 AM EDTMostly Cloudy48°F / 40°F4,304 ftBase above the summit
Sat, Sep 26, 2:00 PM EDTSlight Chance Light Rain57°F / 41°F6,127 ftBase above the summit
Sat, Sep 26, 8:00 PM EDTLight Rain51°F / 44°F4,090 ftBase above the summit
Sun, Sep 27, 2:00 AM EDTLight Rain Likely50°F / 45°F3,616 ftBase above the summit
Sun, Sep 27, 8:00 AM EDTSlight Chance Light Rain50°F / 45°F3,616 ftBase above the summit
Sun, Sep 27, 2:00 PM EDTChance Light Rain51°F / 48°F3,179 ftSummit likely in cloud
Sun, Sep 27, 8:00 PM EDTChance Light Rain50°F / 48°F2,933 ftSummit likely in cloud
Mon, Sep 28, 2:00 AM EDTLight Rain Likely50°F / 48°F2,933 ftSummit likely in cloud
Mon, Sep 28, 8:00 AM EDTLight Rain Likely49°F / 47°F2,914 ftSummit likely in cloud
Mon, Sep 28, 2:00 PM EDTLight Rain50°F / 50°F2,477 ftSummit likely in cloud
Mon, Sep 28, 8:00 PM EDTLight Rain51°F / 51°F2,495 ftSummit likely in cloud
Tue, Sep 29, 2:00 AM EDTChance Light Rain50°F / 50°F2,477 ftSummit likely in cloud

An estimate: the height a rising parcel of the grid’s air would reach saturation, about 125 m for every degree Celsius between temperature and dew point (Espy’s rule), added to the grid’s ground. It fits cumulus and fog made on the spot, not a deck of stratus carried in from elsewhere.

Snow

No snow in the National Weather Service’s forecast for the summit’s grid cell over the next several days.

Sunrise and sunset

DayFirst lightSunriseSunsetLast lightDaylight
September 266:11 AM6:40 AM6:40 PM7:09 PM-12h 0m
September 276:13 AM6:41 AM6:38 PM7:07 PM-13h -3m
September 286:14 AM6:42 AM6:36 PM7:05 PM-13h -6m
September 296:15 AM6:44 AM6:34 PM7:03 PM-13h -10m
September 306:16 AM6:45 AM6:33 PM7:01 PM-13h -12m
October 16:17 AM6:46 AM6:31 PM6:59 PM-13h -15m
October 26:18 AM6:47 AM6:29 PM6:58 PM-13h -18m

For a sea-level horizon at the summit’s position, local time. From a summit the horizon sits lower, so the sun is seen a few minutes before sunrise and after sunset; a ridge to the east or west does the opposite.

Elevation
3,238 ft (987 m)
Prominence
2,182 ft (665 m)
Coordinates
43.8257, -72.0387
Nearest town
Lyme

What this means

Why a summit forecast differs
The air cools with height, by about 3.6°F per 1,000 feet on average, and the wind above a ridge blows at the speed of the free atmosphere rather than slowed by the valley floor. A town’s forecast says little about the top of the mountain above it.
Freezing level
The height where the air is at 32°F (0°C). Above it precipitation falls as snow and wet rock freezes; the snow line usually sits a few hundred to a thousand feet below it.
Wind chill
How cold the air feels on exposed skin, from the temperature and the wind, by the National Weather Service’s 2001 formula.
Cloud base
Where cloud begins. When it is below the summit, the top is in cloud: no view, and in cold air, rime ice and poor visibility.
Prominence
How far a summit rises above the lowest contour line that encircles it and no higher summit: the measure of a mountain’s own height, not its neighbors’.

Nearby

Summits

Ski areas

Forecasts from the National Weather Service. Summit-height temperature, wind and freezing level from NOAA’s Global Forecast System on NOAA Open Data. Summits from Wikidata (CC0): prominence >= 600 m, or elevation >= 4267 m, or >= 12 Wikipedia editions; English Wikipedia article required; read 2026-09-25. Mountain weather changes fast; check the forecast again before you go.