Hawaii Storm Creates Floods, High Winds, Even Snow And Tornado Risk

A KHON reporter gets splashed by water from passing
vehicles as she reports on flooding in Hawaii Thursday.
The island chain is being hit by an unusually
strong storm that will also bring heavy rains
to California this weekend. 

An unusually powerful storm is slapping Hawaii with a wide variety of rough weather. 

The entire island chain was under a high wind warning until noon Friday. Flooding was developing. There was a risk of severe thunderstorms and even the risk of a tornado or two, which is very rare for Hawaii. 

Power outages were already increasing across Hawaii during the day Thursday. Residents inMaui were told to stay off roads due to high winds and flooding. 

As of early Friday several roads were blocked by flooding as rain came down at a rate of one to as much as three inches per hour. 

The city of Kahului on Maui reported an inch of rain in an hour and wind gusts to 50 mph, which is highly unusual stormy for the location. The National Weather Service warned Maui residents of impending significant and life-threatening flash floods and landslides. 

One town in Maui received 13 inches of rain in the storm. A weather station atop a Maui mountain reported a wind gust to 120 mph. 

Honolulu was slammed by more than 3.5 inches of rain, including just under two inches of rain in two hours. That two inches in two hours is more rain than what normally falls on Honolulu during the entire month of January.  

Winter storms sometimes affect Hawaii this time of year, but this one is especially powerful. 

The storm was expected to deepen to 986 millibars, at a latitude a little south of 30 degrees N which is unusual for a storm that far south. It's about the same latitude as northern Mexico.

The storm is close enough to drag a cold front through Hawaii, which is kind of rare for that far south. Ahead of the front, forecasters were worried about rotating thunderstorms that could produce those waterspouts or potential tornadoes. 

 Early Friday our time on the East Coast, the torrential rains were just moving into the Big Island of Hawaii, and new flash flood warnings were issued for parts of that island.  

Atop the highest volcanoes on the Big Island of Hawaii, winter storm warnings were in effect.  Winter storm warnings up there are actually not all that weird for Hawaii.  The summits are expecting five to ten inches of snow, with wind gusts possibly reaching as high as 90 mph. 

ATMOSPHERIC RIVERS

What goes on in Hawaii doesn't stay in Hawaii.  The storm north of Hawaii will contribute to atmospheric rivers that will start hitting California today and intensify over the weekend. 

Flood watches are already up for central California, including San Francisco and Sacramento.  This is a "Pineapple Express" from near Hawaii, as we mentioned so it's a warm atmospheric river. That means rain instead of snow will fall pretty high up the slopes of the Sierra Nevada range. Elevations as high as 7,800 to 8,000 feet look like they are in for rain instead of snow. 

There could even be some flooding near Lake Tahoe. 

Southern California, still suffering from a drought, is expected to mostly miss out on this atmosphere river. It probably won't rain down there until Tuesday. It's just as well the rain in southern California won't be torrential, as that would lead to more mudslides and debris flows in areas that suffered through those huge January wildfires. 

Eventually the atmospheric river could consolidate into a storm that might affect us here in Vermont around next Thursday. Watch this space for updates in the coming days.