'Weather whiplash': Parts of US could see record-high temperatures after freezing storms

Areas across the country were hit with dangerous weather conditions as southern California and parts of the Southeast and Texas responded to flash flood warnings amidst heavy rainfall.

The conditions produced severe flash flooding in San Diego, sweeping away cars and triggering a state of emergency in the area.

On Tuesday, the National Weather Service warned of major flooding in Rochester, Minnesota, and the Cleveland, Ohio, area, with rivers and creeks swelling and rising. Throughout the Ohio River Valley, inches of rain through Thursday could also bring minor flooding to much of Kentucky, the weather service said Tuesday.

The deluge and warmer temperatures this week follow below-freezing temperatures last week in parts of Texas and the South, leading forecasters to say the weather feels like "whiplash."

Parts of the country that have been below freezing for more than a week will finally see temperatures creep up above 32 degrees this week, said David Roth, a lead meteorologist at the national Weather Prediction Center. That means melting snow and ice will likely lead to oversaturated soil, he said.

Loose soggy soil, combined with heavy rain easily contribute to flash floods, Roth added.

"You have the snow and the ice melt contribute to the soil saturation, and then showers and thunderstorms with high enough rain rates come in, and then everything's overwhelmed," Roth told USA TODAY.

In the lower Mississippi Valley and parts of the southern U.S., moisture and instability from the Gulf of Mexico has spawned thunderstorms that will impact the area through Wednesday, according to the National Weather Service. The 4 to 8 inches of rain forecasted could cause flash floods this week in Arkansas, Louisiana, and Texas, and the northwest Gulf Coast into the mid-South.

Louisiana, Mississippi, Alabama and Tennessee are expected to be hit hardest by rain this week. Damaging thunderstorms along the Gulf Coast on Tuesday and Wednesday could cause wind gusts as high as 70 mph, AccuWeather said.

'Weather whiplash'

Odds favor above-average temperatures all week across the entire contiguous 48 states, with highs possibly soaring into the 60s and 70s in some areas of the South, according to the Climate Prediction Center.

UCLA climate scientist Daniel Swain calls it "weather whiplash," as some parts of the country could see record-high temperatures, just a week or so after record lows.

Drizzle was falling in San Antonio on Tuesday morning amid temperatures set to reach the high 60s. Last week, temperatures in the Alamo City and much of Texas dipped as low as the teens.

Heavy rainfall and rapid snowmelt increase the chance for flooding, as a swath stretching from eastern Texas to Tennessee braces for more rain Wednesday through Friday.

Those areas could receive 4 to 6 inches of rain in the coming days, according to AccuWeather senior meteorologist Joe Lundberg.

"That's enough rain to trigger urban and flash flooding even in drought areas, but it may also push some of the secondary river levels up significantly," he said.

Roth said much of Louisiana and Arkansas, where the Ozark rivers in the hills could flood rapidly, are areas that should be concerned about potential flooding this week.

Severe flash floods in San Diego as heavy rain strikes southern California

Meanwhile, severe flash floods hit San Diego County on Monday, wreaking havoc on morning commutes after the torrential rains closed down roads and shut off power. San Diego Mayor Todd Gloria declared a state of emergency after the National Weather Service warned flash flooding could continue until 9 p.m. that night.

Videos posted to social media showed cars washed away as roads turned to rivers. City residents and rescuers used kayaks and paddleboards to bring those trapped to safety.

Hundreds were rescued from homes, according to a city of San Diego statement. Firefighters and lifeguards rescued about two dozen people from the rushing San Diego and Tijuana rivers, the fire department said. Two homeless shelters were also evacuated.

San Diego International Airport reported it had reached a tie for the 5th rainiest day on record, with 2.73 inches of water, according to the weather service. The San Diego River also rose more than 6 feet in less than 12 hours, according to the U.S. Geological Survey.

It was also the city’s rainiest day ever in January, according to records dating to 1850.

The downpours affected much of Southern California, as the weather service reported showers and possible rainstorms throughout Los Angeles County and warned of possible flooding on local roads and freeways. California Gov. Gavin Newsom also declared a state of emergency for San Diego County and Ventura County in response to the heavy rain and flooding.

Boil water advisory for Memphis lifted after 5 days

Memphis’ water company lifted a boil-water advisory for more than 600,000 people on Tuesday, five days after the alert issued for all residents due to extreme weather conditions in the Southeast.

A spate of freezing temperatures in the area dropped water pressure, breaking water pipes in Memphis and Shelby County. Residents were forced to boil tap water at the risk of contamination in the city's water supply.

The city's water company, Memphis Light, Gas and Water (MLGW), issued a notice on Friday urging residents to boil water before consumption due to the risk that water supplies came in contact with dangerous bacteria after the pipe breakages.

The company had also asked residents to conserve water but that order was lifted on Monday morning after MLGW said water pressures across the city were returning to normal.

On Tuesday, MLGW said water quality tests have met state and federal standards, and home and business customers no longer will be asked to boil water before drinking it or using it to brush their teeth and prepare food.

Freezing rain and snowfall reach Midwest and Northeast

Freezing rain will develop in areas across the Midwest, Lower Great Lakes, and the Northeast on Tuesday into Wednesday, the weather service reported. Travel conditions will be hazardous due to a tenth of an inch of ice accretion.

Accumulating snowfall is also likely, especially in parts of lower Michigan and southwest New York.

In Detroit, a winter weather advisory for areas north of Interstate I-69 was in effect until 10 p.m., warning of 1-3 inches of snow and "a light glaze of ice," the National Weather Service said.

On Tuesday afternoon in Buffalo, New York, snow flurries were in the air and a flood watch warned of flooding caused by up to an inch of rain and snowmelt through the end of the week.

Starting Wednesday, southeast Ohio will be under a flood watch through late Thursday.

The series of storm systems across the large areas of the central and eastern U.S. will have milder temperatures compared to the pattern of arctic air from last week. The weather service also forecasts unsettled weather to be ongoing through the middle of the week in the Ohio Valley and large areas of the South.

Ohio weather map

US weather watches and warnings

National weather radar

Contributing: Doyle Rice, USA TODAY; Memphis Commercial Appeal; The Associated Press

This article originally appeared on USA TODAY: Dangerous weather conditions across the U.S. after freezing storms