Information Sources for Winter Weather Forecasting in the White Mountains

There is no single weather forecast that will tell you what the temperature, wind, visibility, snowpack, and trail conditions will be for every location in the White Mountains. As a winter hiker, you will need to piece together forecast data and trip reports from a variety of information sources and make educated guesses about what weather and trail conditions will be like based on the area’s historic weather patterns, terrain attributes, and regional differences.

For example,

• Winds above treeline will be higher than those below treeline.
• Winds at lower elevations will be less severe than those above treeline.
• Mountains with wooded summits will be protected from the full force of the wind.
• Temperatures at higher elevations will be colder than those at lower elevations.
• Trails on the 4000 footers will be broken out after the weekend or several days after a major storm
• Snow depths above treeline will tend to be lower and more windswept than those below treeline.
• Certain regions of the Whites, like the Carter and Wildcat Ranges or the Great Gulf will often have more snow than those further west and south due to the influence of Mt Washington and the Gulf of Maine.

With experience, you’ll learn more of these forecasting heuristics as you do more winter hiking in the area.

Risk Assessment

When you are planning a winter hike and checking up on weather conditions, risk assessment has to be part of the calculation you’re making for yourself and the other members of your party. Many hikes, particularly those below treeline, are often safe unless there are high winds, high windchills, unbridged stream crossings, heavy recent snowfall, or pending winter storms on the horizon.

Above treeline hikes are much riskier and you should get used to making and communicating risk assessments with members of your group for any hike involving an above treeline segment in the Winter Whites. This includes possible risks, turnaround times, and mitigating safety gear or clothing that can help you prepare for adverse conditions. Rescues take a long time to initiate in winter if you need assistance and circumstances can go from bad to worse if you’re out unexpectedly past nightfall. If the shit hits the fan, try to get below treeline. There’s a saying in the Whites, “those who get below treeline live”, that you want to remember whenever you hike above treeline.

Information Sources

The primary sources of weather and trail condition information for the White Mountains are weather forecasts from:

• Mt Washington Observatory Weather Center
• NOAA
• Mountain Weather Forecast
• New England Trail Conditions
• Appalachian Mountain Club
• Randolph Mountain Club
• Mt Washington Avalanche Center
• Recent Hiker Trip Reports aggregated by TrailsNH.com
• Facebook Groups

In the sections below, I’ll explain the different forecasts or reports available from these sources, their strengths and weakness, and how I go about using them to forecast weather and trail conditions in the Winter White Mountains.

Mt Washington Observatory Forecasts

Mt Washington is the highest peak in the White Mountains with an elevation of 6288′.  There is a weather observatory on its summit which publishes many useful weather tools used by hikers to plan winter trips. While the Observatory’s forecasts are useful, most of them have diminishing applicability the farther you get away from Mt Washington and the peaks and subsidiary ridges surrounding it.

Here’s how I interpret the forecasts and reports that the Observatory publishes. Clicking on the links below will take you to the resource described.

• Higher Summits Forecast: Good forecast of what to expect on Mt Washington, its subsidiary peaks and ridges, and other above-treeline trails, 4500′ or higher, throughout the White Mountains. The higher summits forecast also includes timing details of weather fronts passing through the area which is useful for forecasting changes in wind speed (see the Winter Forecasting Concepts article published earlier this week for an explanation of the relationship between winds and weather fronts.)

• Mt Washington Current Summit Conditions Dashboard: Good overview of the conditions on Washington itself. I look at the wind direction, the wind speed, and 15-minute gust speeds to get a sense of the worst-case wind chill on Washington, but the dashboard has limited forecasting value because it doesn’t predict future conditions.

• Mt Washington Valley Forecast: This forecast mainly pertains to the North Conway and Jackson areas on the eastern side of the White Mountains and not the region as a whole. However, I find it to be a fairly reliable indicator of what the temperatures and wind speeds will be below treeline throughout the entire White Mountain region at lower elevations. It’s also one of the few forecasts published by the Observatory which provides a five-day forecast.

• Mt Washinton Regional Mesonet: Three different interactive reports that display real-time sensor information on Mt Washington and other locations scattered around the Whites. The most useful tab is the one labeled “White Mountains Region” because it show differences in wind, temperature, and humidity across different areas of the National Forest. The downside with these reports is that they are near real-time and of limited value for forecasting.

• White Mountain Region Forecast: Relatively worthless. Handed by local motels and B&B’s to persuade guests to not to hike up Mt Washington in winter.

NOAA – National Oceanic and Atmospheric Administration

NOAA is the government agency that oversees the National Weather Forecast. It publishes a ton of very useful wather and climate information and educational material.

• National Weather Forecast Map: This is a map of the United States and Canada that shows where the weather fronts are that relate to New England and the White Mountains. High or low-pressure fronts moving through the region cause winds and bad weather and by looking at this map I can quickly see if we are in a period of stable conditions or if new storm systems are on their way into the area.

• National Weather Forecast Weather Summary: Excellent overview of regional macro-level weather patterns including passing weather fronts. Text only. The detailed explanation is a great way to learn forecasting concepts.

• City and State Forecast: If you plan on hiking in the Whites, you’re probably going to drive through one of the small towns listed below. I like knowing what the weather is like in them for the drive and because I think they provide a reasonable approximation of what below-treeline temperatures are like at nearby trailheads . If you compare each of their forecasts right now, you’re likely to see regional temperature differences between them even though they’re relatively close to one another along the perimeter or interior of the White Mountain National Forest.  Bear in mind that the forecasts you see are computed approximations based on data from the nearest weather station, often a regional airport.
  • Twin Mountain, NH (North Twin and South Twin Mountains, Galehead, Garfield)
  • Gorham, NH (Mount Moriah, North Carter, Madison, Adams)
  • Plymouth, NH (Moosilauke)
  • Lincoln, NH (Mount Liberty, Flume, Cannon, Kinsmans)
  • North Conway, NH (Mount Chocorua, Moats)
  • Jackson, NH (Slide Peak, Isolation)
  • Jefferson, NH (Mount Waumbek, Starr King)
  • Campton, NH (Sandwich Dome, Tecumseh, Tripyramids)
  • Bretton Woods, NH (Mount Tom, Field)

• Point Forecasts: NOAA also provides a point forecasting capability (on the city, state forecast results page) which lets you zoom in on wilderness areas. Bear in mind that these point forecasts are also computer generated approximations and not based on local observations. The forecast at the beginning of this section titled “9 Miles S Twin Mountain NH” is an example of a point forecast for Mt Guyot and the Bonds, four peaks which are deep in the interior of the Pemigewasset Wilderness. The best way to generate a forecast like this is to look up the forecast for the town nearest to your route, and then reposition the green box in the lower right part of the results page over the area you’ll be hiking in. You just need to know where that is relative to the locations shown on the NOAA map provided. In practice, I don’t totally trust this information because I don’t understand how it’s generated and how local elevation or terrain features influence its predictions.

• 48 Hour Key Metric Forecast: This is a sub-report located in the lower right hand corner of NOAA’s 7 day forecast report and one of the most useful forecasts you find for predicting key weather metrics in specific locations 48 hours into the future. The report is based on the location of the current point forecast and lets you browse multiple variables including wind speed, gust speed, temperature, dewpoint, sky cover, thunder, and precipitation forecasts. I have found this report useful for forecasting when winds will increase or decrease above-treeline.

Appalachian Mountain Club

The AMC publishes two daily report about weather, snow accumulations and trail conditions centered around the subset of their mountain huts and lodges that remain open during the winter season.

• Backcountry Weather and Trail Conditions Report: These daily winter observations are taken by local AMC hut caretakers and provide an excellent view of snow, stream crossings, and trail conditions on the ground. I mainly look at the snow accumulation numbers in this report.  The 24 hours number provides a good indication of how much snow will be blowing around in nearby above-treeline locations and whether snowshoes will be needed to break trail. The stake depth is useful for predicting snow depth for bushwhacks.

• Mt Washington and Pinkham Notch Report: This daily report is quite useful because it shows the temperature and wind differences between the above-treeline portions of Mt Washington and those in the valleys surrounding Pinkham Notch where one is likely camp at night. It is highly localized to the immediate area around the base of Mt Washington, but useful if you plan to camp or snowshoe in that area.

Randolph Mountain Club

The Randolph Mountain Club maintains the trail system in the Northern Presidentials on Mounts Madison, Adams, and Jefferson, the second, third, and fourth highest peaks in the White Mountains after Mt Washington. They also manage several cabins which are open year round. The RMC publishes a weekly conditions report from the Gray Knob cabin which is located off Lowe’s Path just below treeline on Mt Adams.  The Gray Knob cabin is an excellent place to shelter overnight before Northern Presidential peak attempts or to retreat to in bad weather.

• Weather Conditions at Gray Knob: I refer to the Gray Knob report to get a feeling for trail conditions and snow depth on the many trails on the north side of Mt Adams and Mt Jefferson, near and above treeline. This area tends to be heavily windswept so snow depths are usually relatively low,  though snow can accumulate after a winter storm.

Mount Washington Avalanche Center

The Mt Washington Avalanche Center provides an extremely valuable service for forecasting avalanche conditions for the Tuckerman and Huntington Ravines on Mt Washington, but it’d be a mistake to assume that these two ravines are the only places that avalanches occur on Mt Washington or in the White Mountains. Avalanches occur throughout the Whites and are much more common than you realize.

• Avalanche Advisory for Tuckerman and Huntington Ravines on Mt Washington: I don’t hike in the Tuckerman or Huntington Ravines but this daily avalanche advisory can provide useful information about recent weather conditions or snow pack makeup that may lead to avalanche conditions on other mountains in the Whites.  If you decide to hike, climb, or ski in such areas, your best source of information will be snowpack observations that you make on the scene. To learn more, you should take an AIARE Avalanche Awareness Level 1 class with the EMS Climbing School in North Conway. They have the best avalanche teachers in the area,

Recent Hiker Trip Reports

One of the best sources of trail condition information in the White Mountains are recent hiker trip reports and there is a long tradition of recording hike summaries and trip reports on local forums and blogs for this purpose. The best way to find these reports is to go to TrailsNH, a trip report search engine which aggregates hiker trip reports on maps of the area, and will let you hyperlink to them directly. TrailsNH also provides other regional information of interest to White Mountain hikers including seasonal road closures, which is very helpful.

I mainly refer to recent trip reports to figure out if the trails I’ll be hiking on are “broken out” or whether I need to bring a posse of other snowshoers along with me. Breaking trail is exhausting work and if you are hiking alone or with just one other person, unbroken trails are best avoided in winter.

Summary

There’s no single weather forecast that you can look up for weather conditions across all of the White Mountains. Local terrain, vegetation, and elevation can all have a huge impact on the weather conditions you experience in different regions of the mountains. As a winter hiker, you may need to piece together many different sources of information to determine whether more challenging routes are safe enough to hike or snowshoe or are best left for more favorable conditions. The ability to do so reliably comes with years of practice and a healthy respect for winter weather conditions.