Health & Safety Requirements

Mount Washington is one of the most extreme and remarkable places on the planet, but not everyone is suited for this environment.

The New Hampshire Fire Marshall's Office requires that all summit visitors and volunteers meet one basic requirement: In the event of an emergency, you must be physically able to "self-evacuate" from the summit. This means you must have the physical ability to get yourself down the mountain, even in extreme conditions. We urge all participants to take this requirement very seriously.

The Mt. Washington Auto Road, which we use to access the summit, is about eight miles long. Approximately half of the road is above tree line. Weather above tree line is often severe, and can turn deadly if you are unprepared, ill-equipped, or unable to hike to safety in the event of a vehicular breakdown.

Note: Trips will not be made far above tree line if the weather is judged to be extraordinarily severe, but even normal weather on Mount Washington can prove lethal to those who are unfit or poorly prepared.

For the safety of all our staff and guests, Mount Washington Observatory asks that you refrain from bringing alcoholic beverages to the summit. A limited selection of beer and wine may be supplied by the Observatory with dinners.
Cell Phone Use: Mount Washington Observatory cannot guarantee cell coverage during your visit. We recommend turning your cell phone to airplane mode for the duration of your adventure. Internet access is available at the Observatory if needed, but otherwise enjoy being disconnected! 

Winter Weather

Our winter operating season is defined as the time when ice and snow engulf the summit, and the Mt. Washington Auto Road is closed to private vehicles. Generally, this is mid-October through mid-May.

An average mid-winter day on Mount Washington finds the summit in rime-ice producing fog, with visibility limited to 100 feet or less, a temperature of about 5°F, and a wind speed near 50 mph. Gusts of 70 mph or greater are likely. A typical wind chill would approach -25°F. It is not uncommon to experience temperatures as low as -45°F, with winds gusting over 100 mph.

Hiking conditions may include drifted snow, glaze ice, sub-zero temperatures, hurricane force winds, and near zero visibility.

Summer Weather

Our summer operating season is defined as the time when the Mt. Washington Auto Road is open to private vehicles. Generally, this is mid-May through mid-October.

An average mid-summer day on Mount Washington has a high temperature of about 53°F and an overnight low of about 42°F, but freezing temperatures can occur during any month of the year. Winds average about 25 mph, with hurricane-force gusts possible. Thick, wet fog occurs on about 90% of the days in summer, and measurable precipitation is recorded about every other day.

Hiking conditions may include frigid temperatures, high winds, blowing precipitation, and limited visibility.

Due to the severity of these conditions, we require that all participants:

  • Are at least 18 years of age or are accompanied by a parent or guardian at all times
  • Are ready, willing, and able to hike to safety on the Mt. Washington Auto Road, which could be up to eight miles on the steep, snow-covered mountain road, or possibly several miles on the rugged trails above treeline, amidst extreme weather conditions, such as blowing snow, thick fog, sub-zero temperatures, and high winds.
  • Are properly prepared with all the required clothing and equipment
  • Understand the risks and hazards of participating in a visit to the Mount Washington Observatory
  • Have to the best of their knowledge, completely filled out any pertinent health and safety information upon registration. If significant changes in health have occurred, please contact with this information. 

Required Clothing & Equipment

A list of required winter gear can be found here.



Mountain weather is subject to rapid changes and extreme conditions. Our forecast is a tool to help you plan a safe trip.

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