Winter storm warning in effect above 12K feet for Mauna Kea, Mauna Loa summits

The second kona low in the past week to strike Hawai’i is fueling another round of nasty winter conditions above 12,000 feet atop the summits of Mauna Kea and Mauna Loa on the Big Island.

A winter storm warning is now in effect through 6 p.m. Sunday, March 22, for both summits, replacing a winter storm watch previously in place.

National Weather Service forecasters in Honolulu report the storm is likely to produce heavy snow and strong winds at the summits beginning tonight and lasting through Sunday afternoon.

Total snow accumulations of up to 10 inches are possible, with winds potentially gusting as high as 70 mph. Light snow could then linger Sunday night into Monday.

Travel could be very difficult to impossible. Blowing snow will significantly reduce visibility at times, with periods of zero visibility.

Any travel plans to the summits should be postponed until the threat for hazardous winter weather diminishes.

The temperature at shortly before 7:30 p.m. Saturday, March 21, atop Mauna Kea was about 27 degrees with a wind chill of about 9 degrees as southwest winds were reaching a sustained speed of 37 mph.

Fog blanketed the summit, with a relative humidity of 100%.

Wind speeds have ranged from a minimum of 17 mph at just after 1:30 a.m. and maximum of 62 mph at about 2:30 p.m. Saturday.

Temperatures during the past 24 hours at the summit ranged from a minimum about 26 degrees at 6:30 p.m. to a 32-degree maximum at 3:30 p.m., with wind chills ranging from about 7 degrees minimum about 6 p.m. to nearly 13 degrees at shortly after 7 p.m. at the max.

Relative humidity has hovered between a minimum 90% at about 12:30 a.m. Saturday to 100% maximum by shortly before 7:30 p.m.

Weather information is from the Maunakea Weather Center at University of Hawai’i at Hilo Center for Maunakea Stewardship.

Blizzard-like conditions forecast at the Mauna Kea summit will make travel there hazardous. Adding to complications is the fact that Maunakea Access Road remains closed to the public at the Maunakea Visitor Information Station level about 9,200 feet.

Mauna Kea rangers reported just after 5:30 a.m. Saturday that the access road remains closed to the summit because of extensive damage caused by recent heavy rains and severe weather caused by the first kona low that slammed into the state last weekend, which brought nearly 2 feet of snow to the summit and wind gusts stronger than 100 mph.

“The Maunakea summit road is undergoing extensive rebuilding,” reported the visitor station in a March 17 Facebook post, adding it was expected to remain closed through at least this week.

The extended closure now also takes into account the forecast for fog, ice and snow that the second kona low this weekend will likely produce at the summit.

Road crews are working as hard as possible to make repairs and will continue daily — when weather permits — until the road is safe for public travel.

“Rangers are monitoring the progress of the roadwork, and also the unstable weather conditions, and the road will be reopened to the public once it is safe,” said rangers in their Saturday access road update. “Mahalo for your patience and understanding, and stay safe.”