Providing Decision Support at 20,310 Feet: The Challenges and Best Practices of Forecasting for North America’s Highest Peak

Denali National Park and Preserve, home to North America’s tallest mountain (Denali 20,310 feet), has been a mecca for mountaineers for over a century. During the climbing season from April to July, the number of climbers on Denali often exceeds the population of many Alaskan villages. Mountaineers come from all over the world to climb Denali, spending two to three weeks acclimatizing and braving the extreme weather characterized by summertime temperatures well below zero, multi-day blizzards, and dangerous winds. The National Weather Service (NWS) Forecast Office in Fairbanks began providing climbing forecasts and Impact-Based Decision Support Services (IDSS) for Denali in 1983. The National Park Service (NPS) staff and climbers rely on the Denali Recreational Forecast to make life threatening go or no-go decisions while attempting to climb the mountain. The severe weather conditions, poor forecast model resolution and guidance, lack of surface observations, and variable microclimates, make forecasting for Denali extremely challenging.

In preparation for the 2017 climbing season, the NWS reevaluated the Denali Recreational Forecast format, various meteorological impact thresholds, dissemination of the forecast on the mountain, and assessed the current IDSS provided to the NPS. Staff from the NWS visited the Denali base camp to see firsthand the terrain climbers encounter on the mountain and how the forecast is used to make critical decisions for planning, safety, and search and rescue operations. Based on feedback and input, NWS Fairbanks created a new suite of IDSS resources and modified existing products and services to meet the latest needs of NPS staff, climbers, and aviation operators on the mountain. The Denali Recreational Forecast was modified to pull information from the gridded forecast database and a dedicated IDSS webpage was developed to improve situational awareness and deliver easy access to the forecast, mountain observations, as well as other resources (satellite, webcams, observations, etc.)

This presentation will discuss the challenges, best practices, and improved IDSS the NWS Forecast Office in Fairbanks is providing to the NPS rangers and climbers on Denali. In addition, new training resources for NWS forecasters and further improvements to the Denali Recreational Forecast and IDSS during the 2018 climbing season will be addressed.