This post explains the National Weather Service advisory for Hawaii’s Big Island summits, where meteorologists forecast up to four inches of snow on Tuesday.
I summarize the advisory’s details, the atmospheric drivers behind the event, the historical context of summit snowfall on Mauna Kea and Mauna Loa, and practical safety guidance for researchers and visitors heading to high elevations.
Summary of the Winter Weather Advisory
The National Weather Service in Honolulu issued a winter weather advisory early Tuesday morning, effective until 6 p.m. HST, for the summits of Mauna Kea and Mauna Loa.
The advisory calls for up to four inches of snow with the possibility of snow mixing with rain at times, and warns that freezing precipitation could create slippery conditions and reduced visibility.
An upper-level low located southwest of the Hawaiian Islands has deepened moisture over the region, setting the stage for wintry precipitation at the highest elevations.
These snow events are driven by the combination of cold summit temperatures and enhanced moisture transport—conditions that are episodic but predictable when the synoptic pattern aligns.
What to Expect at the Summits
Summit elevations on the Big Island exceed 13,000 feet, and at those heights temperatures frequently fall below freezing during the late autumn and wet season.
The advisory expects snow accumulation up to about four inches on the upper reaches of Mauna Kea and Mauna Loa.
Visibility may be poor and surfaces can become icy, particularly where snow mixes with freezing rain.
Why Snow Happens on the Big Island
Although Hawaii is best known for its tropical climate, it routinely experiences snow at very high elevations.
The islands’ volcanic peaks act like mountain ranges elsewhere: altitude overrides latitude.
Snow events are most likely between late October and the wet season when summit temperatures drop low enough for wintry precipitation to occur.
NWS senior meteorologist Maureen Ballard noted a similar advisory was issued on October 25 this season, so this advisory fits a familiar seasonal pattern rather than an anomaly.
Practical Impacts and Safety Measures
Summit roads are often closed during snow events to protect researchers, park staff, and visitors.
The National Weather Service is urging anyone traveling to high elevations to check the latest forecasts and to exercise caution.
Recommended precautions include:
Recreation, Research, and Rare Skiing Opportunities
Hawaii does not have commercial ski resorts, but rare summit snowfalls sometimes attract experienced skiers and snowboarders willing to travel to very specific, often closed, areas.
Those activities carry increased risk due to limited rescue resources and unstable road conditions.
For researchers and support staff working at summit facilities, closures are disruptive but necessary.
Safety protocols and advance planning minimize the impact on scientific operations.
Final Thoughts
This advisory is a reminder of the remarkable meteorological contrasts found on the Big Island: tropical beaches below 100 feet and wintry conditions above 13,000 feet.
Stay informed through official channels, respect closure orders, and prepare appropriately if you must travel to these high-elevation sites.
Here is the source article for this story: Winter weather alert for Hawaii as 4 inches of snow to strike