You'll have about 10 minutes between finding out a nuclear bomb is heading for Washington on a ballistic missile and the moment it explodes over the city.

At least that's the best guess from experts. And that's really a best-case scenario if the bomb comes from a North Korean missile. If it's a Russian or Chinese missile carrying a nuclear bomb? Even less.

Most Washingtonians have spent at least a little time over the past few weeks wondering what's going to happen as Kim Jong Un and President Trump rattle sabers on Twitter and in the press. The nuclear war tightrope is a difficult one to walk, but both men seem determined to do so and it's caused a renewal of interest in what sort of nuclear protocols the city has on hand.

Here's the reality: Nuclear war is just as terrifying now as it was in the Cold War and there's not a lot you'll be able to do to protect yourself — but there are some things.

Tom Nichols, a professor at the Naval War College, says it's very simple.

"The long and short of this is why Eisenhower was not a big fan of civil defense programs. There's not a lot you can do," he said.

Related: Jim Mattis: I thought my staff was playing a joke when I saw 'tenfold' Trump nuclear report

"It will be determined by a lot of luck."

How you'll find out

The very first thing you'll notice is your phone will start going absolutely bonkers.

Brian Baker, the director of the D.C. Homeland Security and Emergency Management Agency, said the agency would notify residents of an incoming nuclear bomb with a cellphone alert, the same way it tells them of a major storm or an Amber Alert for a missing child. Imagine the message saying something like: "ALERT: Nuclear missile headed for Washington, DC! Seek shelter in nearest building away from windows, get underground if possible!"

AlertDC, which is the city's notification system for crimes, major events, weather events, and traffic issues, would also be a major source of communication from emergency officials to the populace.

"AlertDC is one of our key ways, the wireless alerting network … we actually have access to control that directly as well," Baker said. "What you've probably seen is when [the National Weather Service] puts one out, but I have the ability from my operations center to blast out to everyone's phone if there's an immediate protective measure."

Anyone from D.C., Maryland, or Virginia can sign up for AlertDC, but alerts are personalized for each user based on the neighborhoods they're interested in. However, a major incident — such as an incoming nuclear bomb — would reach all of the system's 168,7000 users.

While AlertDC and the emergency notification system are Baker's preferred ways of getting in touch with people, it's not uncommon for people to turn off the setting on their smartphones that allows the government to send that notification.

Luckily, turning off that setting doesn't mean you won't have a chance to prepare yourself for the explosion. Emergency officials could also take over the alert system on the television as well, interrupting every channel in order to give specific instructions on where to go, what to do. Every channel, basically like the weather alerts do.

But not everyone has a cellphone or a television set. So, the notification system can get down to the most basic levels.

"If we need to get information out quickly, we can do that … right down to every one of our public safety vehicles has a public alert system," Baker said, referring to the loudspeakers equipped on police cars and SUVs that patrol Washington. The officers in those vehicles could be notified by radio of an incoming missile by dispatchers, get on the microphone, and begin giving verbal messages to residents who are nearby.

"If it had to come down to that level, we would go to that level."

Between the cellphones all going off at once, the televisions blasting out an emergency notification, and the police vehicles announcing warnings as they ride through the district's streets, this may all sound like a scene from any number of Cold War-era disaster flicks where a city is blown up by a bomb.

But there will be one major difference: Don't expect to hear any sirens.

"For an urban area like this, big voice is more effective than a siren system," Baker said. "Especially in a major city, where a siren going off means different things to different people, and just because a siren's going off it doesn't tell you what protective measures to take."

Ultimately, that's what emergency officials are going to try to do in the last few minutes they have the full means of modern communications technology.

"We want to tell people what to do, not just this is bad, this could possibly happen," he said. "But, stay away from this area, go to a secure location. The message we give is just as important as the notification."

What to do

Let's just get this out of the way first: You're not going to run away from the bomb.

"It makes no sense to run," Nichols said. "You don't know how accurate the bomb is. For all you know, you're running toward it. That bomb could go off anywhere within a few miles."

You're better off getting inside and finding a basement. If that's not an option, the best place to be is in a central room in a building with no windows and no border with the outside.

Use the same rules that apply in tornado drills or shelter-in-place drills in school. And after you find the safest room you can get to, you'll want to duck and cover.

No, seriously.

"When you're talking about a bomb the size North Korea would have, that was great advice," Nichols said. "Get down, cover your head, don't stand there in the middle of Central Park and gawk. Get under something."

Two main things kill people during the initial explosion of a nuclear weapon: a massive fireball that's brighter than the sun and a shockwave that will shatter glass, buildings, and any other solid object in its way.

Related: University of Hawaii sends 'in the event of a nuclear attack' email to students and faculty

While some believe North Korea tested a 250 kiloton hydrogen bomb in September, the biggest bomb the Hermit Kingdom tested previously was about 10 kilotons. Since experts believe North Korea can't currently attach any nuclear warhead to a ballistic missile, let's assume for this story they were able to figure out how to launch a 10 kiloton warhead toward Washington.

First, don't look at the blast. This is one of the reasons that duck and cover is so important. When the explosion comes, you can use some techniques to ensure you're not immediately incapacitated, said Irwin Redlener, a Columbia University professor who specializes in disaster planning, response, and recovery.

"You want to keep your mouth open, so your eardrums don't burst from the pressures," he said in a TED talk about such a scenario. "If you're very close to what happened, you actually do have to duck and cover, like Bert told you, Bert the Turtle. And you want to get under something so that you're not injured or killed by objects, if that's at all possible."

Bert the Turtle is a lead character in a 1951 animated Federal Civil Defense Administration film that taught children how to duck and cover in the event of a nuclear bomb exploding in the area.

But if you work or live somewhere within a three-block radius of the blast, what you do is irrelevant.

"If you're close enough that the heat is a problem, there's not a thing you can do," Nichols said.

In that space — for the White House that's the area between 13th and 19th streets NW to the east and west, and L Street NW and Constitution Avenue to the north and south — everyone is likely to die. The blast of the bomb will destroy even the sturdiest concrete buildings.

The scariest thing about a nuclear bomb blast is this may be the best place to be if you're going to fall victim to the bomb. Outside of that range, death is still nearly guaranteed, but it becomes far more horrifically and slowly.

A massive dose of radiation can be expected in a 3 square mile area around the center of the blast that will kill 50 to 90 percent of the people who are exposed. According to Alex Wellerstein, a science historian at the Stevens Institute of Technology, it would take the people in this zone somewhere between hours and weeks to perish.

In the 4 1/2 square miles around the blast, most residential buildings will collapse, Wellerstein reports. Nearly everyone in this zone will be injured. Thousands will die.

"The worst place to be is going to be outside the area of immediate fatalities," Nichols said. "That's the unenviable place."

Outside of this area, many of the immediate deaths will be caused by windows shattering and sending bullets of glass through human bodies, lacerating flesh, and causing many to bleed out.

According to Wellerstein's estimates, a 10 kiloton nuclear bomb that explodes over the White House would kill 130,230 people and injure about 173,000 more.

Surviving the aftermath

If the bomb's gone off and you're still alive, you're not out of the woods yet. Really, you're just getting to the hard part.

If you're lucky enough to have sheltered in a building, and it didn't collapse, your best bet is to stay put, Nichols said.

"I would stay right where you are because once you're outside and walking around, you're going to be out there with an army of the walking wounded," he said. "If you have emergency skills and you want to get out there and help, then by all means. But, otherwise, you're going to be emerging from a place of relative safety into an area of complete chaos."

But the biggest reason you'll want to stay inside after a nuclear explosion is fallout.

Fallout is material blasted into the atmosphere in a nuclear explosion that's highly radioactive. That fallout will fall to the Earth like a snowstorm — a snowstorm that will dissolve your skin, poison your blood, or give you cancer that will slowly kill you in the coming years.

Redlener believes it'll take about 20 minutes for that fallout to start landing back on the ground. You could take the chance of running a mile away from the blast to avoid the worst of the fallout in that time, but your best bet is to find a safe place to shelter and plan on staying there for about three days.

"If you're in the direct fallout zone here, you really have to either be sheltered or you have to get out of there, and that's clear. But if you are sheltered, you can actually survive," he said.

The federal government has, not surprisingly, come up with a detailed guidance plan to respond to a nuclear bomb explosion. Their first piece of advice is similar: If you're alive, stay inside.

First responders will be rushing toward the blast zone following the explosion and will make their way through three areas: the Light Damage Zone, the Moderate Damage Zone, and the Severe Damage Zone.

Basically, they'll ignore the Light Damage and the Severe Damage zones, according to a federal guidance document.

"Responders should resist spending time and resources on minor injuries in order to maximize the use of medical resources on more critical needs closer in to ground zero," the document, titled "Planning Guidance For A Nuclear Detonation," states. "Response actions in this zone should be focused on encouraging individuals to stay safely sheltered so that responders can expedite access to MD zone casualties."

This Light Damage Zone, the area more than 3 miles away from the blast, will be marked by debris and rubble scattered about and more minor injuries. The area outside of 3 miles away from the blast is expected to be mostly non-radioactive.

However, the Moderate Damage Zone will be a hellish scene to behold.

The sturdiest buildings will remain standing, but less sturdy buildings will no longer be structurally sound. Fires will be raging, ignited by the heat from the blast and damaged utility lines. Luckily, the design of American cities will probably keep a Hiroshima-style firestorm from happening, but fire will be a major problem in this area.

"The need for search and rescue will far exceed the resources that will likely be obtainable," the document states. "Search and rescue missions should be practicable in the MD zone, and may target locations with high likelihood of multiple survivors, or with special populations (e.g., schools or hospitals), or in discrete locations such as tunnels and subways."

Related: What war with North Korea might look like

The Severe Damage Zone is likely to be ignored for weeks by first responders simply due to the fact it's unlikely anyone in that area will have survived. But, if you're in that zone and managed to live through, the best chance you have at staying alive is staying right where you are.

You'll likely survive if you find a place that can withstand the blast, avoid catching on fire, and can shield you from dangerous radiation.

The day after a nuclear blast will bring a severe reduction in the radioactive properties of the fallout. Spending that time inside will allow for safer evacuation when first responders eventually reach your area.

"While sheltering is a priority for protecting public health, it goes against natural instincts to run from danger and reunify with family members," the document states. "The need for reunification is especially true for parents who are separated from their children at the time of the event. Communications aimed at families and those who want to evacuate will be critical to successfully keeping people inside."

Put more succinctly by Nichols, "Stay in your home, stay where you are. The last thing emergency responders need is people wandering around."

There's a good chance the attack will knock out power and many modern conveniences we've come to rely on. The best way to receive information following the attack would be from good, old-fashioned radios, Baker said.

"This is Disaster 101: Have a radio, have batteries. That'll be the way we're able to push out information when cellphones die," he said. "Radios will be a key way of getting information out."

The moment will eventually come when a first responder comes to tell you it's safe to evacuate. They'll point you toward water, food, medical facilities, and whatever else you need. If you're not injured, plan on getting there on your own two feet. If you are injured, evacuation would take longer.

If you've gotten to this point, you really can't ask for too much more.

Parts of the city will likely have to be abandoned for months, if not years, until they're inhabitable again. Law and order could break down as people get desperate for shelter, food, and water. Who knows what effect such an attack could have on the structure of the government and the future of the country.

The key, Redlener says, is to get lost once you've been found.

"But basically, you've got to get out of town as quickly as possible. And if you do that, you actually can survive a nuclear blast."