Severe thunderstorms and flooding rain pounded parts of the Northeast, Midwest and South during the Fourth of July holiday weekend, including New York, Washington, D.C., and Chicago — something all too familiar in the heart of summer.

It was a deadly, chaotic holiday weekend

Eight were killed and another 18 injured due to thunderstorms from Friday through Monday across the country.

On Friday, severe thunderstorm wind gusts estimated at up to 100 mph capsized a boat on Geneva Lake, Wisconsin, claiming three lives. Also that afternoon, one was killed and three were injured from a lightning strike on Fort Myers Beach, Florida.

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Saturday, two were killed and one injured by downed trees in a campground in Cumberland County, Pennsylvania, while another was killed in Millbrook, Illinois, when a tree fell on a camper trailer.

Monday, one was killed and three were injured when a thunderstorm toppled a tree onto a home in Zephyrhills, Florida.

Then there was the chaos and disruption from severe thunderstorms and flooding rain.

Multiple rounds of severe thunderstorms raked through New York City on Friday and Saturday, pushing some boats adrift in New York Harbor, downing tree limbs and knocking out power.

(MORE: The underrated danger of falling trees)

In Washington, D.C., tens of thousands were evacuated from the National Mall into various federal buildings when thunderstorms moved in, delaying festivities commemorating the 250th anniversary of the adoption of the Declaration of Independence.

Chicagoland had four separate rounds of severe thunderstorms, dumping up to 8 inches of rain with damaging winds and a widespread Fourth of July flash flood in the city's western and southern suburbs.

If that wasn't enough, the Monday after the holiday weekend, flooding rain swamped areas from Long Island and New Jersey to Ohio and South Dakota, leading to water rescues, some flooded homes and even a collapse of a New Jersey warehouse club's roof.

Is this amount of severe weather unusual?

The short answer is no, but that's not to say this wasn't an impressive rash of severe weather.

From July 3-5, there were over 1,300 reports of severe weather across the country, including over 1,200 reports of thunderstorm wind damage or high winds, according to NOAA's Storm Prediction Center.

The Fourth of July was the most active day for severe weather reports so far this year, with 675. The previous day was the sixth most active day (475 reports).

Meteorologists define severe thunderstorms as those that produce tornadoes, hail at least the size of quarters (1 inch diameter), wind gusts of at least 58 mph or wind damage.

We often see higher numbers of wind damage reports in severe thunderstorm events in the East, given both the higher population and the denser tree cover susceptible to thunderstorm winds.

But it's also summer.

Summer's heat and humidity often fuel scattered thunderstorms in many areas of the country, even in Alaska.

But if it's particularly hot and humid, as we just witnessed in the East and Midwest during the holiday weekend, these thunderstorms can turn severe with hail and/or damaging winds, enough to capsize a boat, topple trees, knock out your power or just turn your beach day into a wind-whipped tempest.

June and July typically have the most reports of severe thunderstorm wind damage or high winds in the U.S.

Thunderstorms don't have to be deemed "severe" by meteorologists to be dangerous.

June, July and August are peak months for lightning in the U.S., and summer also lies in the heart of flash flood season.

(MORE: Activities with the most lightning deaths in the US)

Here's how to stay safe

How do you enjoy the warmth of summer outdoors, but also stay as safe as possible from thunderstorms?

Be aware of the forecast.

• Check your forecast before your outdoor plans.
• If there's a chance of thunderstorms, check out an hourly forecast (such as on The Weather Channel app) to see when they may be a threat.
• Does your forecast mention a threat of severe thunderstorms or heavy rainfall? Pay even closer attention to the forecast if so.

Use a weather app when you're outside.

• Turn on rain, lightning and severe weather alerts. These are also available on The Weather Channel app.
• Find out where you can quickly seek safe shelter if thunderstorms develop. The best shelter is a solid building, not an open-air picnic shelter.
• Check your weather app's radar to see if any thunderstorms are developing or moving in your direction.

Take action before storms arrive.

• If you receive a severe weather or lightning alert on your weather app, or you're alerted to dangerous weather at a concert or sporting event, move to safe shelter immediately. 
• Even if you don’t receive an alert, if your weather app's radar loop shows thunderstorms are approaching or if darkening clouds are moving in, move to safe shelter, especially if that shelter is some distance away. Don’t wait for the first lightning strike. 
• Stay in shelter until at least 30 minutes after you hear the last rumble of thunder, or until local officials at a large event give an all clear.
• Check the radar on your weather app to make sure no other storms have formed or are moving toward your area. 

(MORE: How to stay safe before, during and after a flood)

Jonathan Erdman is a senior meteorologist at weather.com and has been covering national and international weather since 1996. Extreme and bizarre weather are his favorite topics. Reach out to him on Bluesky, X (formerly Twitter) and Facebook.​