Blizzard hits Hawaii as Sierra Nevada snowpack gets really deep

It’s been a strange year for weather so far, and a recent series of events has confounded expectations.

On Tuesday and Wednesday, a blizzard hit mountaintops on Hawaii’s Big Island. Most of the snow fell overnight, blanketing the summit of Mauna Kea with eight inches and making the road to the summit impassable. In California, meanwhile, record levels of rain and snow look set to lift much of the state out of drought come spring. Across much of the rest of the country, however, the expected winter precipitation never materialized.

It’s not the weather events in themselves that are surprising, weather forecasters say – it’s the intensity of storms, rainfall, and even dry weather.

Despite Hawaii’s reputation as a tropical paradise, the peaks, which are nearly 14,000 feet high, do get snow in the winter months. Mauna Kea, the highest point in the state, has a sub-Arctic climate, the weather service told USA Today. But this week’s snow, which prompted a blizzard warning on Tuesday and Wednesday, was unusually strong, intensified by the fact that the weather system lingered over the state.

"The reason for the snow amounts being heavier than we usually see is that the upper low [pressure system] really persisted down there, that has allowed colder air to remain locked in place," Andrew Orrison of the National Weather Service's Weather Prediction Center told Reuters.

In California, meanwhile, the Sierra Nevada has received an unexpected snowfall of its own. During the drought of the past few years, surveyors measuring the snowpack have had little – or even nothing – to measure. This year, by contrast, the mountain range, which provides one-third of the state’s water, is full almost to bursting.

"Right now we're looking at potentially an all-time record for rainfall and you have to go back to the winter of 1982-83 for snow pack being as deep as it is," Mr. Orrison said.

Thanks to this rain and snow, less than 10 percent of the state remains in drought, the National Drought Mitigation Center said on Thursday. Experts warn, however, that this runoff will not instantly replenish the groundwater that has been pumped during years of drought. And the volume of the water has created other challenges, overwhelming infrastructure like the Oroville Dam in northern California and costing the state about $1 billion.

Nevertheless, Orrison emphasizes that “there has just been substantial improvement” in California’s state of drought. Gov. Jerry Brown is waiting for measurements in April to make a final decision about lifting the state of emergency imposed during the dry years.

The precipitation levels in the two Pacific neighbors since the beginning of 2017 stand in stark contrast to those across much of the rest of the country. Mauna Kea’s eight inches of snow outpaced, in one night, the volumes recorded in Chicago, Denver, and Philadelphia over the past two months, Hawaii News Now reported.

This report contains material from Reuters.