After days of severe flooding in Florida, that and many other states are bracing for an extreme heat wave, while the Pacific Northwest is expecting unseasonably cold weather and late snowfall is expected in the Rocky Mountains early next week.
The chaotic weather map shows the possibility of severe thunderstorms between hot and cold fronts. Meteorologists said the colliding fronts could cause flash flooding between eastern Nebraska and northern Wisconsin on Saturday night, and severe storms could move across parts of eastern Montana and into North and South Dakota.
Meanwhile, a plume of tropical moisture will reach the central Gulf Coast over the next few days, and heavy rains are expected Monday morning, according to the National Weather Service.
“They’re all connected,” said David Roth, a meteorologist with the National Weather Prediction Center in College Park, Maryland. “The heat that will build over the Midwest and Northeast is because we have an unusually pronounced weather pattern in June.”
A low pressure system to the northwest brought isolated thunderstorms and hail to Seattle and other western Washington cities during the afternoon, and freeze warnings prompted gardeners in northern Idaho to cover sensitive plants for the weekend.
In Phoenix, temperatures reached 104 degrees Fahrenheit at 5 p.m. and were expected to climb several degrees higher. Lee Franklin, a spokesman for the Phoenix Public Library, said more than 5,000 visitors have sought respite at libraries’ cooling centers so far, including a new 24-hour cooling center at the Burton Barr Library.
“We definitely see the need and benefit of our heat relief efforts on these hot days,” Franklin said.
Meteorologists say the threat of heavy rain in Florida continues to decrease, but some thunderstorms could cause flooding given the already soaked ground. Some areas between Miami and Fort Lauderdale have been under water in recent days as storms dumped up to 20 inches of rain in southern parts of the state.
The destructive, unnamed storm system coincided with the start of hurricane season in early June. This year’s season is expected to be one of the most violent in recent history, amid fears that climate change will increase the intensity of the storms.
Temperatures rose in much of the southern country on Saturday.
In Atlanta, where highs of nearly 100 degrees Fahrenheit were forecast for both weekend days, city officials opened a cooling center to provide relief. The city also postponed a Family and Friends Field Day due to the heat.
And in the West Texas city of El Paso, highs of 105 degrees Fahrenheit were expected Saturday, and the National Weather Service issued a heat advisory for the region through Monday morning. The city has opened five cooling centers that will operate daily until further notice.
Although Arizona is just beginning its three-month monsoon season, when changing wind patterns typically bring moisture from Mexico’s tropical coast, no rain is forecast for most of the coming week.
“There is no chance of rain across the state,” said National Weather Service meteorologist Ted Whittock, noting that southeastern Arizona has a 30% chance of rain next Friday.
An atmospheric flow of moist air is being channeled into the upper Midwest, causing an unusually “moderate risk of excessive precipitation” in Minnesota from Sunday into next week, Roth said.
“Heavy rain events like this don’t happen very often. We’re forecasting up to 7 inches of rain in Minnesota — you can’t overstate how unusual that is,” Roth said. The last time the state saw that much rainfall in a single event was in 2008, he said.
In Tennessee, tens of thousands of revelers at the Bonnaroo Music & Arts Festival braved a hot, sunny weekend to attend more than 150 performances at the 700-acre campground and concert grounds that host the annual event. While medical staff treated various heat-related ailments, some fans built elaborate canopies and tent combinations for shade. Others had their sunscreen stripped away upon entry because large bottles and aerosol cans were not available, The Tennessean reported.
Temperatures in the Mid-Atlantic and New England next week are likely to reach between 95 and 104 degrees Fahrenheit, which is “nothing to sneeze at even in the middle of summer, let alone this early in the summer,” said National Weather Service meteorologist William Churchill. High humidity will make it feel even hotter in many places, he added.
Expected highs in the Northeast could set daily and even monthly records in the next few days, Roth said. Even in northern Maine, the chances of reaching 100 degrees are very low, he said.
“The town of Caribou in northern Maine normally counts how many days a year it is 80 degrees. The fact that it can even get to 100 degrees is very unusual,” said Roth.
Last year, the United States experienced the most heat waves — unusually hot weather lasting more than two days — since 1936. In the South and Southwest, last year was the worst year on record, according to the National Oceanic and Atmospheric Administration.
While the sun blazes across much of the country, a winter storm warning has been issued for parts of Montana, with the possibility of wet snow that may last through Monday night.
Churchill said the northwest cold front was related to the heat wave because one extreme is often accompanied by the other.
Heavy rain and isolated thunderstorms were expected in Western Washington through Saturday evening. In Edmonds, where an outdoor arts festival was taking place, the National Weather Service warned in the early afternoon that a stronger thunderstorm was approaching.
Hikers and other outdoor enthusiasts in Montana’s Cascade Mountains and Rocky Mountains will likely see snow at lower elevations than normal. The National Weather Service has issued a winter weather advisory for northern Idaho and western Montana from Sunday through Tuesday.
The agency warned of the risk of hypothermia and said remote roads could become impassable due to expected snowfall and possible falling trees and branches.
Up to 6 inches of heavy, wet snow was expected in the mountains around Missoula, Montana, and up to 20 inches was forecast in the higher elevations around Glacier National Park.
