Update: Flash flood warning for Custer County forecast to expire at 6:15 p.m.

Published Aug 27, 2025

The warning was in place for Custer County.

“Flood waters have receded. The heavy rain has ended. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures,” says the National Weather Service.

Deciphering advisories, watches, and warnings: Understanding weather alerts

• Flash flood warning: Take action!

A flash flood warning is issued when a flash flood is imminent or occurring. If you are in a flood-prone area, move immediately to high ground. A flash flood is a sudden violent flood that can take from minutes to hours to develop. It is even possible to experience a flash flood in areas not immediately receiving rain.

• Flood warning: Take action!

A flood warning is declared when flooding is on the verge of happening or is already underway.

• Flood advisory: Be aware:

A flood advisory is issued when flooding is not expected to be bad enough to issue a warning. However, it may cause significant inconvenience, and if caution is not exercised, it could lead to situations that may threaten life and/or property.

• Flood watch: Be prepared:

A flood watch is issued when conditions are favorable for flooding. It does not mean flooding will occur, but it is possible.

Be flood-ready: Expert guidance from the NWS for your safety

Floods can pose a significant threat, especially if you live in a flood-prone area or find yourself camping in a low-lying region. To ensure your safety, the NWS offers essential flood safety guidelines:

Seek higher ground:

If you reside in a flood-prone region or are camping in low-lying terrain, the first step to safety is relocating to higher ground.

Follow evacuation orders:

When local authorities issue an evacuation order, promptly comply. Before leaving, secure your home by locking it.

Disconnect utilities and appliances:

If time allows, disconnect your utilities and appliances. This reduces the risk of electrical hazards during flooding.

Avoid basements and submerged areas:

Steer clear of basements or rooms where water has submerged electrical outlets or cords. This helps prevent electrical accidents.

Evacuate promptly for safety:

If you notice sparks or hear buzzing, crackling, snapping, or popping noises, evacuate immediately. Avoid any water that may be charged with electricity.

Stay away from floodwaters:

Never attempt to walk through floodwaters, even if they appear shallow. Just 6 inches of fast-moving water can forcefully sweep you off your feet.

Seek high ground if trapped:

Should you become trapped by moving water, reach the highest point possible and dial 911 to contact emergency services.

During heavy rainfall, there is a risk of flooding, especially in low-lying and flood-prone areas. Remember to never drive through water on the road, even if it seems shallow. According to the NWS, as little as 12 inches of rapidly flowing water can carry away most cars. Stay safe by being prepared and informed.

Driving through downpours: Safety guidelines for wet roads

Rain can turn roads into hazards. Stay informed and follow these tips from the NWS to ensure safety during heavy rainfall:

Beware of swollen waterways:

During heavy rain, avoid parking or walking near culverts or drainage ditches, where swift-moving water can pose a serious risk.

Maintain safe driving distances:

The two-second rule for following distance is your ally in heavy rain. Extend it to four seconds to ensure safe spacing in adverse conditions.

Reduce speed and drive cautiously:

On wet roads, reducing your speed is crucial. Ease off the accelerator gradually and avoid abrupt braking to prevent skidding.

Choose your lane wisely:

Stay toward the middle lanes – water tends to pool in the outside lanes.

Visibility matters:

Enhance your visibility in heavy rain by activating your headlights. Be particularly vigilant for vehicles in blind spots, as rain-smeared windows can obscure them.

Watch out for slippery roads:

The initial half-hour of rain is when roads are slickest due to a mixture of rain, grime, and oil. Exercise heightened caution during this period.

Keep a safe distance from large vehicles:

Don’t follow large trucks or buses too closely. The spray created by their large tires reduces your vision. Take care when passing them as well; if you must pass, do so with caution.

Mind your windshield wipers:

• Overloaded wiper blades can hinder visibility. If rain severely limits your sight, pull over and wait for conditions to improve. Seek refuge at rest areas or protected spots.

• When stopping by the roadside is your only option, position your vehicle as far off the road as possible, ideally beyond guardrails. Keep your headlights on and activate emergency flashers to alert other drivers of your position.

By following these safety measures, you can significantly reduce risks and ensure your well-being when heavy rain pours down. Stay informed about weather conditions and heed advice from local authorities to make your journey safe and sound.

Source: The National Weather Service