The National Weather Serv­ice has issued a red flag warning for leeward areas of all Hawaiian Islands as strong wind and low humidity heighten the risk for wildfires. The warning is in effect today from 10 a.m. to 6 p.m.

“A combination of strong winds, low relative humidity, and dry fuels can contribute to extreme fire behavior,” forecasters said. “Any fires that develop will likely spread rapidly. A red flag warning does not predict new fire starts.”

The weather service predicts east wind of 20 to 30 mph with gusts up to 45 mph, and relative humidity as low as 40% to 45%.

Forecasters advise:

>> Outdoor burning is not recommended.

>> Heat from vehicle exhaust systems can ignite dry grass. Park cars on areas that are paved or where vegetation is trimmed and cleared.

>> Delay activities that could throw off sparks until the wind dies down.

In addition, a high-surf advisory is in effect for the east shores of Oahu, Maui, Molokai, Hawaii island and Kauai through 6 a.m. Saturday with waves building up to 8 to 12 feet by today.

Weather officials caution that these waves could pose hazards along the shoreline, particularly in exposed coastal areas.

On land a wind advisory is in place through 6 a.m. Saturday for Lanai, Maui, Molokai and Hawaii island. The NWS warns that the strong wind could lead to downed trees and power outages, particularly in exposed and elevated areas.

Also, a small-craft advisory remains active for coastal waters around the islands, where rough seas could make conditions hazardous for smaller vessels.

Gusty tradewinds are expected to continue across the state through the weekend, bringing periods of showers focused mainly on windward and mauka areas, according to the NWS. Some showers also might reach leeward regions as the wind carries rain bands over the islands.

A pocket of drier air is forecast to move into the islands today, but increased moisture is expected to return by Saturday, likely resulting in a rise in shower activity, especially along windward slopes and coasts.