Cold front to bring a chilly Halloween
60 million people under warnings
Temperatures are plummeting across the central and eastern United States as a strong fall cold front blasts across the nation. In some cases, the drop-off is in excess of 30 degrees, bringing about a sudden seasonal reversal as a late-season taste of summer is replaced by wintry weather.
Sixty million Americans are under frost or freeze alerts, which stretch from the Big Bend of Texas to the Great Lakes and Ohio Valley. Those alerts are expected to be extended toward the East Coast midweek.
In the Rocky Mountains, the cold air came with a hefty snowstorm and even a few claps of thundersnow over the weekend. The south side of Denver received between 8 and 10 inches of snow, with 7.5 inches falling at Denver International Airport. Among first snowstorms of the season, it’s the fifth-biggest on record dating to 188.
A separate batch of snow plastered the northern Rockies and northern Plains late last week into the weekend, leaving behind in excess of a foot of snow in North Dakota.
The cold shot looks to be short-lived, however, with a warm-up on the way. The National Weather Service’s Climate Prediction Center predicts above-average temperatures to build across the West later this week and expand eastward by the start of next week.
On Monday morning, the cold front was draped from Cape Cod to the Mississippi River Delta in southeast Louisiana; in between, it passed near Washington, D.C., the Carolina Piedmont and just northwest of Atlanta. Temperatures were dropping 15 to 25 degrees along the front as Canadian high pressure built in its wake.
Ahead of the front, southwesterly winds allowed temperatures to climb to record values. Dulles International Airport just west of D.C. hit 86 degrees Fahrenheit on Saturday, its highest reading observed so late in the year. Nearby Reagan National Airport managed an 86 as well, and Baltimore got to 85. Boston set a record at 81 degrees over the weekend, while New York City hit 80 and Philadelphia surged to 83 degrees.
The rapidity with which temperatures have fallen has been particularly impressive. In Perryton, Tex., for example, Friday’s frontal passage came with a temperature drop of 16 degrees in just 40 minutes. Winds also abruptly gusted to 44 mph as the front swung through.
In Houston, temperatures hit 89 degrees on Sunday. The National Weather Service’s forecast high was 49 for Monday — a day-to-day drop of 40 degrees. In fact, the 41-degree drop that occurred in 15 hours between 3 p.m. Sunday and 6 a.m. Monday ties as the most dramatic temperature drop on record in Houston during the autumn.