Fresh on the heels of a blast of unseasonably chilly summer weather earlier this week, yet another shot of cool air is expected across parts of the United States in just a few days. Those hoping for a break from the dog days of summer have something to look forward to.
Let's look at the chilly forecast ahead and what we've seen so far.
Forecast: Another Chilly Blast Coming
Moderating temperatures have returned to the Central U.S. and will continue through Friday as the chilly air mass begins to retreat and the still-strong August sun does its work.
PHOTOS: Weird summer weather throughout U.S.
Weird summer weather throughout U.S.
Record cold air retreats, but another chilly blast is on the way
Click through to see more images of weird weather around the U.S.
Cal Fire engineer Clint Singleton looks out at a plume of smoke near Clearlake, Calif., Wednesday, Aug. 5, 2015. Thousands of firefighters battling an unruly Northern California wildfire were aided overnight by cooler temperatures and higher humidity, but the fire is still less than a quarter contained. (AP Photo/Jeff Chiu)
Corn damaged by heavy rains stands in a field in Sheridan, Ind., Wednesday, Aug. 12, 2015. The U.S. Department of Agriculture says farmers in 88 of Indiana's 92 counties are eligible for low-interest emergency loans because of heavy rains and flooding that have occurred since May 1. (AP Photo/Michael Conroy)
In a view from Whittier, Calif., the sun sets behind a hazy downtown Los Angeles after a week of high temperatures from the view Tuesday, Aug. 18, 2015. (AP Photo/Nick Ut)
A child plays in the sprinklers of Seward park, Monday, Aug. 17, 2015, in New York. Temperatures are expected to reach into the 90s in the New York metro area. (AP Photo/Mary Altaffer) (AP Photo/Mary Altaffer)
Beach goers crowd at Venice Beach, Calif., Sunday, Aug. 16, 2015. The Western heat wave began Thursday and was expected to continue through Sunday. Authorities warned people not to leave small children or pets in cars, where temperatures can quickly soar. Los Angeles and other cities were keeping libraries and other facilities open late to serve as cooling shelters for those without air conditioning.(AP Photo/Ringo H.W. Chiu)
Storm clouds build over the left field stands in Coors Field during the fifth inning of an inter league baseball game between the Seattle Mariners and the Colorado Rockies Monday, Aug. 3, 2015, in Denver. (AP Photo/David Zalubowski)
Debris rests on the ground after a garage was damaged by fallen tree during a severe thunderstorm in Traverse City, Mich., Sunday, Aug. 2, 2015. Authorities said gusts as high as 65 mph left thousands without power, damaged houses and left some roads impassable. (AP Photo/John Flesher)
A vehicle drives through a puddle after heavy rainfall, Tuesday, Aug. 11, 2015, in Albany, N.Y. Scattered rain and thunderstorms are expected in the region through Wednesday. (AP Photo/Mike Groll)
Firefighters walk under smoke from fires along Morgan Valley Road near Lower Lake, Calif., Friday, July 31, 2015. A series of wildfires were intensified by dry vegetation, triple-digit temperatures and gusting winds. (AP Photo/Jeff Chiu)
LAKE MEAD NATIONAL RECREATION AREA, NV - AUGUST 03: The ruins of the Hannig Ice Cream Parlor are shown in the ghost town of St. Thomas on August 3, 2015 in the Lake Mead National Recreation Area, Nevada. The town was founded in 1865 by Mormon pioneers at the site where the Muddy River flowed into the Colorado River and at one point had about 500 settlers. The town was abandoned in 1938 after the construction of the Hoover Dam caused the Colorado River to rise. The area was once submerged in 60 feet of water but became entirely exposed to the air as a severe drought in the Western United States over the last 15 years has caused Lake Mead to drop to historic low levels. (Photo by Ethan Miller/Getty Images)
UNITED STATES - JULY 30: A severe thunderstorm passes over the U.S. Capitol on Thursday, July 30, 2015. (Photo By Bill Clark/CQ Roll Call)
Clouds accompany hot, muggy weather over downtown Los Angeles and the Walt Disney Concert Hall, Thursday, July 30, 2015. July is wrapping up in California with more of the unusual weather that has marked the normally very dry month. Flash-flood watches are posted across the interior mountains and deserts of southern and eastern California as monsoonal moisture brings thunderstorms.(AP Photo/Nick Ut)
Motorists drive through heavy rain along Ninth Avenue, Thursday, July 30, 2015 in New York. More showers are predicted through the night, but skies are expected to clear by Friday morning. (AP Photo/Julie Jacobson)
Two youths play in the Swann Memorial Fountain Thursday, July 30, 2015, in Philadelphia. According to the National Weather Service temperatures are expected to reach 90-degrees. (AP Photo/Matt Rourke)
Young people cross a street during a rainstorm Thursday, July 30, 2015, in Philadelphia. According to the National Weather Service temperatures are expected to reach 90-degrees. (AP Photo/Matt Rourke)
Walter Swinehart cools off in the Swann Memorial Fountain, Thursday, July 30, 2015, in Philadelphia. According to the National Weather Service temperatures are expected to reach 90-degrees. (AP Photo/Matt Rourke)
A man cools off in the water sprinklers at Sara Delano Roosevelt Park, Wednesday, July 29, 2015, in New York. The National Weather Service has issued a heat advisory for New York City through 8 p.m. Thursday. (AP Photo/Mary Altaffer)
Clouds hang over City Hall Tuesday evening, July 28, 2015, in Commerce City, Colo. Forecasters predict continued warm weather for Colorado's Front Range communities in the week ahead. (AP Photo/David Zalubowski)
Storm clouds build over the Rocky Mountains in Colorado as the sun sets late Friday, July 24, 2015. Forecasters predict that the cool, stormy weather of Friday will move out for daytime highs hovering in the 90s for the weekend ahead. (AP Photo/David Zalubowski)
In this Tuesday, July 21, 2015, photo, Wendover Mayor Mike Crawford stands along the exposed mud track on the Bonneville Salt Flats, in Utah. Crawford, who owns an auto parts shop in town, said the decision by race organizers to cancel this yearâs event weeks away will be a bigger economic blow than last year, when a monsoon storm left standing water on the track on the eve of the race. Wet weather has forced the second-straight cancellation of an annual race at Utahâs world-famous Bonneville Salt Flats. (AP Photo/Rick Bowmer)
A teenager checks his cell phone as storm clouds pass Friday, July 17, 2015, in Zionsville, Ind. Scattered storms were in the forecast for most of Friday evening. (AP Photo/Darron Cummings)
Storm clouds hang over Great American Ball Park before the MLB All-Star baseball game, Tuesday, July 14, 2015, in Cincinnati. (AP Photo/Jeff Roberson)
Smoke drifting south from wildfires burning in Canada clouds the skyline Tuesday, July 7, 2015, in Denver. A smoke advisory was issued for the northeastern part of Colorado, Monday and expanded to all counties east of the Continental Divide Tuesday. (AP Photo/David Zalubowski)
Vehicles struggle to navigate through the intersection of Eighth Avenue and Grant Street south of downtown Denver as a severe thunderstorm swept over the metropolitan area late Thursday, June 25, 2015. Forecasters have issued a severe thunderstorm warning for communities south and east of Denver for Thursday night. (AP Photo/David Zalubowski)
NEW YORK, NY - AUGUST 17: People enjoy a hot afternoon at the Astoria Pool in the borough of Queens on August 17, 2015 in New York City. The main pool, the biggest in New York City and administered by the New York City Department of Parks and Recreation, sees over 3,000 people on a typical summer weekday. New York city is in the middle of a heat wave, with temperatures in the high nineties and with a heat factor making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
Discover More Like This
BACK TO SLIDE
However, this change is not expected to last. Another cold front will bring strong to severe thunderstorms to the Midwest on Saturday, followed by yet another significant cooldown in many areas to close out the weekend and begin next week.
Highs in the 50s and 60s will infiltrate parts of Montana, northern Wyoming and the western Dakotas on Saturday. This is about 15 to 25 degrees below late-August averages. The cool air will then spread throughout the Plains and Midwest on Sunday, dropping high temperatures 10 to 20 degrees below average from the Texas Panhandle and central Oklahoma to the Dakotas and Minnesota.
Lows in the 30s will once again grip parts of the northern and central Rockies this weekend, with 40s and low 50s likely spreading through parts of the northern and central Plains and Upper Midwest Sunday and Monday.
The frontal system ushering in the cool air may also bring some more snow to the northern Rockies. Some light accumulations of snow are possible above 7,000 feet in Glacier National Park late Friday and Friday night, according to the National Weather Service. In addition, frost is possible in the valleys of western Montana this weekend.
Midweek Record Lows and Rockies Snow
A strong cold front now approaching the East Coast dragged much cooler air into the Rockies, Plains and Upper Midwest. Not only were there record low temperatures at night, but daytime temperatures across parts of the northern states struggled to climb out of the 50s thanks to widespread cloud cover and steady rain.
It was so cold Wednesday morning that a coating of snow fell at Rocky Mountain National Park. Although snow is not completely unheard-of across the highest peaks in late summer, the National Weather Service in Boulder, Colorado said it was likely the first snow of the season for the area. In Montana, low temperatures bottomed out in the upper 20s Tuesday and Wednesday morning at West Yellowstone.
Some daily record lows were recorded Wednesday and Thursday east of the Rockies:
- Denver set a daily record low of 47 degrees Wednesday morning.
- Lubbock, Texas, dipped to a new daily record low of 57 degrees just before midnight Wednesday evening.
- Oklahoma City dipped to 50 degrees Thursday morning, beating its previous record for Aug. 20 of 56 degrees. This was the lowest August temperature there since 1915 and was also one degree shy of the all-time August record low.
-Wichita Falls, Texas, also set a daily record low on Thursday morning, bottoming out at 56 degrees.
Texarkana, Arkansas set an all-time coolest high temperature for August as the thermometer only climbed to 71 degrees on Thursday. Several locations also set daily record cold high temperatures on Thursday, including Dallas and Waco which only saw the mercury reach 73 degrees and 74 degrees, respectively. Shreveport, Louisiana also saw a record cold high temperatures on Thursday with a high of only 76 degrees.
The Science Behind the Chill
As usual, the jet stream – that ribbon of fast-flowing air some 30,000 feet above the ground that encircles the Northern Hemisphere – has been a key player.
The pattern this week features a pattern we haven't seen much of this year – one with short, sharp southward dips moving quickly from west to east within the jet stream. One of them crossed the north-central U.S. earlier this week, allowing cold air from Canada to slide down into the Rockies and Plains. It also spun up a strong area of low pressure near ground level, bringing a fall-like area of overcast skies and wind-driven rain on its northern and western flank. The clouds and rain blotted out enough sunlight to keep daytime temperatures from rising at all in some areas.
The southward kink in the jet stream – what meteorologists call a "shortwave trough" – has been large enough to bring that big push of cool air, but not so large as to pinch off from the main jet stream. As we've seen many times in recent years, that could have created a cutoff low and led to a blocking pattern in the atmosphere, causing weather patterns to stagnate.
Instead, the shortwave has continued rippling along to the east, allowing the brief warmup in the middle of the country and dragging the cold front toward the East Coast.
Another shortwave will come along this weekend, and that will bring that next intrusion of chilly air described in the forecast above.
Meteorologist Chris Dolce and senior meteorologist Nick Wiltgen contributed to this report.