Hawaii snow warning cautions drivers that travel could be difficult

National Weather Service (NWS) meteorologists at the Honolulu, Hawaii, office warned that snow on Big Island summits could make for difficult travel on Monday.

October is the start of Hawaii’s wet season, which runs through April. On Monday morning, meteorologists issued a winter weather advisory for the Big Island. According to the forecast, “deep moisture will continue to move over the area today, leading to periods of rain and snow on the high summits.”

It is not uncommon for snow to fall on Hawaii’s volcanic peaks given their altitude, and even blizzard warnings have been issued in Hawaii during the winter months. At times, advanced skiers travel to Hawaii to ski the volcanic slopes, although there are no ski resorts in the state.

On Monday, the storm was expected to produce mixed precipitation with periods of rain and snow.

“Additional snow accumulations up to 3 inches, mainly in the morning. Travel could be very difficult. Blowing snow will significantly reduce visibility at times, with periods of zero visibility,” the advisory said. “A winter weather advisory means that periods of snow, sleet or freezing rain will cause travel difficulties. Be prepared for slippery roads and limited visibilities, and use caution while driving.”

NWS meteorologist Liam Tsamous told Newsweek that it is unclear how much snow has already fallen on the high-elevation peaks, given that there are no observation stations there. Up to 4 inches of rain has fallen in low-elevation areas, he said.

At nearly 14,000 feet above sea level, the Mauna Kea volcano is the tallest peak in Hawaii. It is the world’s tallest mountain when measured base to peak, as its base extends nearly 20,000 feet below sea level.

The volcano is so high that it occasionally experiences snowfall during the summer months as well. Tsamous said it is not uncommon to see snow on the mountain’s peaks in October.

The storm was also bringing excessive rain to the rest of Hawaii, with most lower-elevation areas under a flood watch.

“An upper low in the vicinity of the Hawaiian Islands is producing unstable conditions within a very moist atmosphere,” the flood watch said. “This will result in periods of moderate to locally heavy showers. Rain that occurs over already saturated ground could quickly lead to runoff and flash-flooding issues.”

The flood watch remains in effect for all the main Hawaii islands through Monday afternoon, the advisory said.

“Flood-prone roads and other low-lying areas may be closed due to elevated runoff and overflowing streams,” the flood watch said. “Urban areas may receive more significant flooding and property damage due to rapid runoff.”