Tropical Storm Iselle has closed in on Hawaii in the first of a one-two punch to be delivered over the week-end.
Structural damage, downed trees and widespread power outages have been reported, along with some flooding.
Hurricane Julio, a Category 3 storm, follows some 900 miles behind, but forecasters say it will skirt north of all the Hawaiian islands when it hits early Sunday.
Julio currently packs maximum winds of 120 mph but is expected to weaken. Iselle, the first tropical storm to hit Hawaii in 22 years, crossed the big island early Friday with winds at 60 mph.
Athough Iselle was downgraded to a tropical storm, officials still urged precaution.
The state's governor has the National Guard on alert.
"We're really at the beginning stage of this," Gov. Neil Abercrombie, D-Hawaii, said. "We're really like only the first quarter, so let's be sensible. Let's stay calm."
Local and state governments have closed offices, schools and transit services across Hawaii. Schools have cancelled classes and many businesses are closed. The airport in Honolulu remains open, although dozens of flights are delayed or cancelled.
Primary elections on Saturday, including congressional and gubernatorial races, are expected to go forward.
Authorities are not reporting any deaths or major injuries from Iselle. So far, the greatest damage includes downed trees, roof damage and about 20,000 homes without power.
Forecasters say the storm will bring 5-8 inches of rain to Hawaii, with up to a foot in some areas.
Storms in Hawaii are rare but not unexpected in El Nino years, when changes in ocean temperature affect weather around the world. Earlier this year weather officials warned that Hawaii could see 4-7 tropical storms in 2014.