Summertime conditions fuel flash flooding warnings in the Northeast; homes evacuated after California landslide: Weather updates

Hot and stormy weather pressed on Sunday as summertime conditions fuel severe thunderstorms in parts of the United States while the Southwest faces another week of intense heat.

The active weather pattern of heat and humidity is threatening a large area of the central United States with severe thunderstorms into the early week, AccuWeather said. Hail, gusty winds, and some tornadoes are expected to impact a smaller portion of the region.

But heavy and excessive rainfall in addition to damaging winds are the main severe weather threats for parts of the East.

The Central Plains into portions of the Mississippi and Tennessee valleys will be targeted by severe weather conditions through Sunday night, according to AccuWeather. The National Weather Service issued flash flooding warnings and watches Sunday for parts of the Northeast.

And in the Southwest, sweltering conditions are again increasing temperatures above average with triple digit heat expected into the week. Scorching temperatures are expected to cause "widespread moderate to high heat risk" and locally, extreme risks in the deserts, according to the weather service.

"The source of this upcoming heat is a large, sprawling ridge of high pressure positioned over the Southwest," said AccuWeather meteorologist Andrew Johnson-Levine. "This will help to keep most showers or storms at bay and allow for sunny skies that will help boost temperatures."

Meanwhile, other dangers affected the southern regions of Florida and California.

A massive dust cloud from Africa's Sahara Desert reached South Florida on Saturday, causing hazy skies. In Southern California, a landslide Saturday night forced 12 homes to evacuate after cracks were found forming on a property.

Severe weather: Northeast under flash flooding alerts

Parts of the Northeast were on high alert for flash flooding risks, according to the weather service.

More than half a foot of rainfall is possible from Sunday to Tuesday as the slow-moving weather system turns into parts of the mid-Atlantic and New England, AccuWeather said. Tropical moisture over the region will bring excessive rain that can be potentially damaging along the Carolinas to Maine.

"Rainfall rates could reach 2 inches per hour in some locations as the system slowly moves," said AccuWeather meteorologist Adam Douty. "Infrastructure in the metro areas may not be able to handle rainfall of this magnitude, and as a result, rising water could quickly inundate some locations."

High levels of water and flooded roadways were reported in several areas in eastern and southeastern Pennsylvania, AccuWeather said. Rainfall up to two to four inches was also reported across the region by Sunday afternoon, according to local observation sites.

Portions of southern New York, such as the Hudson Valley, were experiencing life-threatening flash flooding, according to the weather service. A flash flood emergency was issued for the area and New York Gov. Kathy Hochul issued a state of emergency for Orange County on Sunday night.

The New York State Police said numerous roadways were experiencing heavy flooding and washouts, causing road closures. Emergency management officials in New York City warned heavy rain could cause basements to flood and residents were advised to prepare to move to higher ground.

Sizzling temperatures bring record heat

The scorching heat across the Southwest is expected to elevate wildfire threats, heat-related illnesses, and strain the energy grid.

A northward bulge in the jet stream will hover across the Southwest for the week but is expected to gradually shift to the Plains by next week, according to AccuWeather.

AccuWeather said several heat records will be challenged throughout mid-July in the Southwest.

In El Paso, Texas, the record for most consecutive 100+ degree days was broken Sunday as the city reached 24 days of triple-digit heat.

"This beats the old streak of 23 set in 1994," the weather service in El Paso said on Twitter. "Looks like plenty of more 100+ degree days on the horizon."

12 homes evacuated in Los Angeles County amid landslide

A neighborhood south of Los Angeles was on alert after cracks were found on a property Saturday night, FOX Weather reported.

According to Janice Hahn, the chair of the Executive Office of the Los Angeles County Board of Supervisors, 12 homes in Rolling Hills Estates were threatened by a "major" landslide and were evacuated on Saturday night.

The homes were along a canyon and were deemed "too unstable" to enter, Hahn said on Twitter. All residents were safe.

In an update Sunday, Hahn said the homes were "completely destroyed" by the landslide and were pulled off their foundations. As of Sunday afternoon, the land was continuing to move but the evacuation order remained limited to the 12 homes.

The land movement "could be due to the extensive rains that we’ve had .... but we don’t know," said Paul Goodrich, a building official with the city Rolling Hills Estates, the Los Angeles Times reported. A historic weather front slammed a wide swath of Southern California with stunning snow, record rains, and flooding this past winter.

Saharan dust in South Florida

Dust carried from Africa's Sahara Desert reached South Florida on Saturday, causing the area's blue skies to turn opaque and has the potential to impact air quality.

Forecast models from the National Hurricane Center show that dust clouds could affect Florida and the entire Gulf Coast throughout the next week. While the dust is not a rare occurrence, according to AccuWeather forecasters, it could still cause poor air quality and hazy skies.

According to the NOAA, dust clouds from the Sahara Desert typically form during the late spring, summer, and early fall. The mass of dry, dusty air moves over the North Atlantic Ocean every three to five days and can carry upwards of 66 million tons of dust annually over the ocean and the Americas.

During its peak period in the summer, it is common for some dust outbreaks to move farther west, including Florida, Central America, and Texas.

Contributing: Samantha Neely, Fort Myers News-Press

This article originally appeared on USA TODAY: Weather forecast Sunday: Flash flooding warning parts of Northeast