Maine mountains

White Cap Mountain mountain forecast

3,655 ft (1,114 m) · prominence 2,605 ft (794 m) · Maine

At the summit’s height the GFS model has 52°F and wind from the ENE at 16 mph, Sat, Sep 26, 2:00 AM EDT. The freezing level is at 13,120 ft, above the summit. The National Weather Service forecast for saturday: partly sunny, high 57°F at its grid elevation of 3,596 ft.

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The summit on the map

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

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Now

Summit
3,655 ft (1,114 m)
Forecast grid ground
3,596 ft (1,096 m)
Summit temperature
52°F
Summit wind
ENE 16 mph
Freezing level
13,120 ft
High at the summit, by lapse rate
57°F

The last tile carries the Weather Service’s high from its grid’s 3,596 ft up 59 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 EDT52°FENE 16 mph13,120 ft9,465 ft above the summit
Sat, Sep 26, 8:00 AM EDT50°FENE 23 mph43°F13,619 ft9,964 ft above the summit
Sat, Sep 26, 2:00 PM EDT53°FENE 20 mph14,098 ft10,443 ft above the summit
Sat, Sep 26, 8:00 PM EDT53°FENE 27 mph13,547 ft9,892 ft above the summit
Sun, Sep 27, 2:00 AM EDT48°FENE 29 mph40°F13,031 ft9,377 ft above the summit
Sun, Sep 27, 8:00 AM EDT49°FE 33 mph40°F11,844 ft8,189 ft above the summit
Sun, Sep 27, 2:00 PM EDT50°FE 30 mph12,992 ft9,337 ft above the summit
Sun, Sep 27, 8:00 PM EDT50°FE 29 mph12,930 ft9,275 ft above the summit
Mon, Sep 28, 2:00 AM EDT49°FE 27 mph41°F12,388 ft8,734 ft above the summit
Mon, Sep 28, 8:00 AM EDT49°FE 26 mph41°F12,297 ft8,642 ft above the summit
Mon, Sep 28, 2:00 PM EDT48°FE 21 mph41°F12,221 ft8,566 ft above the summit
Mon, Sep 28, 8:00 PM EDT47°FESE 21 mph40°F11,680 ft8,025 ft above the summit

NOAA’s GFS model, run Fri, Sep 25, 8:00 PM EDT, interpolated to 3,655 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 12 mphMostly cloudy, with a low around 47. Northeast wind around 12 mph.
SaturdayHigh 57°FNE 12-15 mphPartly sunny, with a high near 57. Northeast wind 12 to 15 mph.
Saturday NightLow 47°FNE 14-24 mphA slight chance of rain after 2am. Mostly cloudy, with a low around 47. Northeast wind 14 to 24 mph. Chance of precipitation is 20%.
SundayHigh 53°FNE 16-25 mphA slight chance of rain before 1pm. Mostly cloudy, with a high near 53. Northeast wind 16 to 25 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
Sunday NightLow 41°FNE 20-30 mphRain likely. Mostly cloudy, with a low around 41. Northeast wind 20 to 30 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
MondayHigh 48°FNE 9-23 mphRain. Mostly cloudy, with a high near 48. Northeast wind 9 to 23 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Monday NightLow 45°FNE 13-16 mphRain. Cloudy, with a low around 45. Northeast wind 13 to 16 mph. Chance of precipitation is 90%.
TuesdayHigh 49°FNE 3-12 mphRain likely before 8am, then a chance of rain showers between 8am and 5pm. Mostly cloudy, with a high near 49. Chance of precipitation is 70%.
Tuesday NightLow 46°FN 5 mphMostly cloudy, with a low around 46.
WednesdayHigh 57°FW 5 mphPartly sunny, with a high near 57.

The Weather Service’s forecast asked at the summit’s coordinates (45.5547, -69.2463), by its office in Caribou, ME. Its grid cell is 2.5 km across and sits at 3,596 ft (1,096 m), 59 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 EDTPartly Sunny48°F / 38°F5,879 ftBase above the summit
Sat, Sep 26, 2:00 PM EDTMostly Cloudy55°F / 35°F8,162 ftBase above the summit
Sat, Sep 26, 8:00 PM EDTMostly Cloudy52°F / 40°F6,325 ftBase above the summit
Sun, Sep 27, 2:00 AM EDTSlight Chance Light Rain50°F / 42°F5,419 ftBase above the summit
Sun, Sep 27, 8:00 AM EDTSlight Chance Light Rain49°F / 39°F5,856 ftBase above the summit
Sun, Sep 27, 2:00 PM EDTMostly Cloudy50°F / 39°F6,102 ftBase above the summit
Sun, Sep 27, 8:00 PM EDTChance Light Rain51°F / 42°F5,665 ftBase above the summit
Mon, Sep 28, 2:00 AM EDTLight Rain Likely47°F / 41°F4,949 ftBase above the summit
Mon, Sep 28, 8:00 AM EDTLight Rain Likely44°F / 40°F4,521 ftBase above the summit
Mon, Sep 28, 2:00 PM EDTLight Rain Likely42°F / 42°F3,614 ftSummit likely in cloud
Mon, Sep 28, 8:00 PM EDTLight Rain46°F / 45°F3,833 ftBase above the summit
Tue, Sep 29, 2:00 AM EDTLight Rain48°F / 47°F3,828 ftBase above the summit

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 265:59 AM6:29 AM6:29 PM6:58 PM-12h 0m
September 276:01 AM6:30 AM6:27 PM6:56 PM-13h -3m
September 286:02 AM6:32 AM6:25 PM6:54 PM-13h -7m
September 296:03 AM6:33 AM6:23 PM6:52 PM-13h -10m
September 306:04 AM6:34 AM6:21 PM6:50 PM-13h -13m
October 16:06 AM6:35 AM6:19 PM6:49 PM-13h -16m
October 26:07 AM6:37 AM6:17 PM6:47 PM-13h -20m

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
3,655 ft (1,114 m)
Prominence
2,605 ft (794 m)
Coordinates
45.5547, -69.2463
Nearest town
Greenville

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.