Update: The fire warning expires at 7 p.m.

The warning was addressed to Sussex, Warren, Morris, Hunterdon, Somerset, Middlesex and Mercer counties.

“Winds begin to subside and relative humidity levels rise as temperatures cool after sunset,” the National Weather Service said.

What is the meaning of a red flag warning?

A red flag warning means extreme fire weather conditions are either occurring now or will occur soon, according to the weather service. Warm temperatures, very low humidity and stronger winds are expected to combine to create an increased risk of fires spreading quickly.

So what do you do when there is a red flag warning?

During a red flag warning, it is essential to exercise extreme caution and be prepared to take immediate action in the event of a fire. The weather service suggests the following steps you can take to reduce the risk of fire and keep you safe:

1. Ensure the safety of burning barrels:

• If burning is legal in your area, make sure all burn barrels have a weighted metal lid with holes no larger than 3/4 inch.

2. Responsible disposal of smoking materials:

• Do not randomly throw away lit cigarette butts or throw cigarettes or matches from moving vehicles. These seemingly harmless actions can ignite dry vegetation, potentially leading to a wildfire.

3. Properly extinguish outdoor fires:

• To prevent accidental fires, carefully extinguish all fires in the open air. Fill them with plenty of water and stir to make sure everything is cool to the touch. Submerge the charcoal in water until it cools completely. Never throw burning coal onto the ground.

4. Never leave a fire unattended:

• Do not leave fire unattended. Even sparks or embers carried by the wind can ignite nearby leaves or grass, causing a fire that spreads quickly.

Understanding the severity of a Red Flag warning and following these precautions are critical to reducing the risk of wildfires in these dangerous conditions. Prioritize safety, stay informed, and act responsibly to protect lives and property.

Advance Local Weather Alerts is a service provided by United Robots that uses machine learning to collect the latest data from the National Weather Service.