The National Weather Service on Wednesday issued a red flag warning for the leeward sides of the Hawaiian islands, the first such warning since the deadly Lahaina fire over three weeks ago.

The alert, prompted by dry vegetation, strong and gusty tradewinds, and low humidity, is expected to be in effect until 6 p.m. today.

Forecasters noted, however, that winds will not be comparable in strength to the Aug. 8 downslope windstorm on Maui that saw gusts of over 60 mph help drive the flames that overwhelmed much of historic Lahaina town, killed at least 115 and destroyed 19 houses Upcountry.

For this event, expect tradewinds 15 to 30 mph with gusts of 40 to 50 mph. The strongest wind gusts will be downwind of higher terrain. Minimum humidity of 45% to 55% should lower to 35% to 45% today.

Officials said the combination of strong winds, low relative humidity and dry fuels can contribute to extreme fire behavior, and any fires that develop will likely spread rapidly.

In advance of the warning, officials with Maui County and Hawaiian Electric Co., who have been at odds over the cause of the deadly Aug. 8 Lahaina wildfire, issued a joint statement Tuesday night to assure the public that they will work together, along with state officials, to prepare and respond to the high fire risk weather conditions.

“With high winds and severe drought conditions continuing to threaten parts of Maui, we are working together to minimize the risk of wildfire and ensure public safety. … We will do what we have always done when confronted by hardship and heartbreak — we will stand together for our people and communities and work to keep them safe,” said the statement issued by Maj. Gen. Kenneth S. Hara, adjutant general of the Hawaii Department of Defense, Maui Mayor Richard T. Bissen Jr., and Shelee Kimura, president and CEO of Hawaiian Electric.

Wednesday on the Big Island, Hawaii County Mayor Mitch Roth and Civil Defense Administrator Talmadge Magno were urging the community to take any steps necessary to prevent fire and protect property.

“We’re asking our residents to protect each other by being cautious and remaining mindful in their actions,” Roth said in a news release. “Last time we had similar conditions, multiple fires sprung up along our leeward coast. These fires can potentially put our firefighters and communities at large in harm’s way. By remaining mindful and refraining from potentially risky behaviors, we can significantly reduce the chances of large brush fires this time around.”

The county also canceled camping permits within leeward beach parks, including Mahukona Beach Park, Spencer Beach Park, Kohanaiki Beach Park, Punaluu Beach Park and Whittington Beach Park.

The county also prohibited open flames, fire pits and grills on county property “until further notice.”

In its statewide warning, the National Weather Serv­ice said outdoor burning is not recommended, urged the delay of activities that could throw off sparks and warned that heat from vehicle exhaust systems can ignite dry grass.

“Park cars on areas that are paved or where vegetation is trimmed and cleared,” the alert said.

For more information and fire prevention tips, visit the Hawaii Wildfire Management Organization at hawaiiwildfire.org.