Answers to common questions about disasters, safety, government and public programs in the United States, drawn from the questions Americans search most and linked to our reporting. For the latest stories, see our U.S. section.
- What does "flash flood" mean?
- What was the worst flash flood in US history?
- What is worse, a 100-year flood or a 500-year flood?
- How to get out of a wildfire?
- What are the 5 P's of evacuation?
- What is the president's daily brief?
- Do former presidents still get daily briefings?
- How long does an accident investigation take?
- Is it better to have straight Medicare or a Medicare Advantage plan?
- Which Medicare plan is free at age 65?
What does "flash flood" mean?
A flash flood is a rapid rise of water in a normally dry or low-lying area, usually within six hours of heavy rain, a dam or levee failure, or a sudden release of water. The National Weather Service ranks flash floods among the deadliest weather hazards because they can arrive with little warning, as hikers found in Grand Canyon National Park in August 2026.
Source: National Weather Service. Our coverage: Search Goes On for Missing Hiker After Deadly Grand Canyon Flash Flood
What was the worst flash flood in US history?
The deadliest U.S. flood was the Johnstown Flood of May 31, 1889, when the South Fork Dam failed above Johnstown, Pennsylvania, and a wall of water killed 2,209 people. Among rain-driven flash floods, the 1976 Big Thompson Canyon flood in Colorado killed 144 people, and the July 2025 floods in the Texas Hill Country killed more than 130.
Source: National Park Service, Johnstown Flood National Memorial
What is worse, a 100-year flood or a 500-year flood?
A 500-year flood is the larger and rarer event. The labels describe odds, not timing: a 100-year flood has a 1 percent chance of being equaled or exceeded in any given year, and a 500-year flood has a 0.2 percent chance. Both can happen in back-to-back years, and a home in a 100-year floodplain has about a 26 percent chance of flooding over a 30-year mortgage.
Source: U.S. Geological Survey
How to get out of a wildfire?
The safest way out of a wildfire is to leave early, as soon as officials issue an evacuation order or even before, using the routes they announce. Fire agencies teach "Ready, Set, Go": prepare a go-bag and plan, stay alert to warnings, and leave when told. If you are trapped in a car, park away from vegetation, close the vents and stay inside.
Source: Ready.gov. Our coverage: Hawk Fire Burns Homes in Northwest Reno as Tens of Thousands Flee
What are the 5 P's of evacuation?
The five P's are a quick evacuation checklist promoted by emergency managers: people and pets; prescriptions, including medicines, eyeglasses and medical equipment; papers, such as IDs and insurance documents; personal needs like clothes, water, food and phone chargers; and priceless items, such as photos and keepsakes. Packing them ahead of time saves minutes when an evacuation order comes.
Source: Ready.gov. Our coverage: Hawk Fire Burns Homes in Northwest Reno as Tens of Thousands Flee
What is the president's daily brief?
The President's Daily Brief is a top-secret summary of intelligence and analysis prepared each day for the president and a small group of senior officials. It is produced under the Director of National Intelligence, with the CIA supplying much of the analysis. In September 2026 the CIA released 71 briefs from 1998 to 2001 that traced warnings about Osama bin Laden before the 9/11 attacks.
Source: Wikipedia. Our coverage: Declassified CIA Briefs Trace Years of Bin Laden Warnings Before 9/11
Do former presidents still get daily briefings?
Former presidents do not receive the President's Daily Brief. By tradition, a sitting president may allow predecessors to request intelligence briefings as a courtesy, but no law requires it. President Biden ended Donald Trump's briefings in 2021, and after returning to office President Trump revoked Joe Biden's security clearance and access to briefings in 2025.
Source: Wikipedia. Our coverage: Declassified CIA Briefs Trace Years of Bin Laden Warnings Before 9/11
How long does an accident investigation take?
For major transportation accidents, the National Transportation Safety Board usually releases a preliminary report of basic facts within about 30 days. The full investigation, which ends with a final report and a probable cause determination, typically takes 12 to 24 months. The NTSB is leading the inquiry into the September 2026 crash of a firefighting helicopter on Yosemite's Dome Fire.
Source: National Transportation Safety Board. Our coverage: Two Contract Pilots Die as Firefighting Helicopter Goes Down Over Yosemite's Dome Fire
Is it better to have straight Medicare or a Medicare Advantage plan?
Neither is better for everyone. Original Medicare covers any doctor or hospital that accepts Medicare nationwide but has no yearly out-of-pocket cap unless you add a Medigap policy. Medicare Advantage plans, run by private insurers, cap annual costs and often add dental or vision benefits, but usually use provider networks and prior authorization, and plans can leave a county from one year to the next.
Source: Medicare.gov
Which Medicare plan is free at age 65?
Medicare Part A, which covers hospital stays, is premium-free at 65 for most people who, or whose spouse, paid Medicare taxes for at least 10 years. Part B, which covers doctor visits, carries a monthly premium for nearly everyone. Some Medicare Advantage plans advertise a $0 premium, but enrollees still pay the Part B premium plus any copays and deductibles.
Source: Medicare.gov
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