While most of the state enjoys a tropical climate year-round, Hawaii's mountaintops are no stranger to winter weather.

A University of Hawaii web camera showed snow on the ground along the guardrails of one of the Mauna Kea astronomy observatories on Friday morning.

A slow-moving low pressure system is making its way through Hawaii before exiting later Saturday, bringing snow to the summits on the Big Island.

A Winter Weather Advisory was issued until 6:00 a.m. Saturday local time.

Forecasters are calling for up to 2 inches of snow.

Hawaii's mountains are mainly volcanoes, including Mauna Kea on the Big Island, whose summit is nearly 14,000 feet above sea level.

Mauna Kea is the tallest mountain on the planet when measured from it's base which extends below the ocean floor.

While snow is not uncommon among the tall peaks of Hawaii's Big Island, you might think by April the snow would be done. 

But over the past 20 years, the Big Island has averaged about one snow advisory in April.

Snow advisories have been issued as late as June.

That comes as Kilaueua, one of the world's most active volcanoes, erupted for the 18th time since last December earlier this week.

While the system will bring snow to the mountain peaks, that moisture will be just plain rain closer to sea level. 

Temperatures in Hilo will make it up into the 80s this weekend.