Many could be forgiven for not realizing that fall -- at least by one definition -- arrived on Sept. 1 given above-normal warmth stretching across much of the U.S. That trend is likely to continue for weeks, and the weather may become more active on several fronts in October.
Published Sep. 1, 2022 1:34 PM EDT | Updated Sep. 2, 2022 10:06 AM EDT
September has arrived, marking the return of pumpkin spice lattes, football season and cooler weather, but AccuWeather long-range forecasters say that it may take some time for the latter to come to fruition across the United States.
Meteorological autumn officially kicked off on Thursday, Sept. 1, and will continue through Wednesday, Nov. 30. AccuWeather meteorologists say that it will not feel like the seasons have changed across more than two-thirds of the nation as above-normal warmth will persist.
One month has passed since AccuWeather released its annual U.S. fall forecast, and since then, Senior Meteorologist Paul Pastelok and his team of long-range forecasters have continued to pour over proprietary data, refining the seasonal outlook.
August was historically inactive across the tropical Atlantic, but that does not rule out an above-normal season overall, AccuWeather forecasters caution. An uptick in systems is projected to occur later than it normally does, and additional impacts are expected in the United States.
Summer weather has dealt out opposite extremes across the nation. For some places, precipitation was nearly non-existent with drought the rule as other locations couldn't catch a break from unrelenting rain. Deluges have led to five separate "one in 1,000-year" flood events since late July.
AccuWeather has you covered on whether fall will tip the scale on the weather pattern and offer relief in the coming months. Forecasters break down all that you need to know as the season gets underway.
La Niña to help reignite Atlantic hurricane season
The weather pattern in the Southeast will be influenced by several factors this autumn, including the unusually warm waters of the Gulf of Mexico and a significant climate pattern unfolding thousands of miles away.
For the third year in a row, La Niña will be one of the dominant factors in the global weather pattern. La Niña occurs when the waters in the equatorial Pacific Ocean are cooler than normal, which can influence global weather patterns, including a higher potential for tropical systems to develop across the Atlantic hurricane basin.
The Atlantic basin has been uncharacteristically quiet since Colin quickly formed and fell apart in early July with an extended drought of named system. The basin was already showing signs of increased activity as Tropical Storm Danielle developed on Sept. 1. August was historically tranquil with zero named storms. This is only the third time since the end of World War II that there was no named storms throughout August, joining 1961 and 1997.
However, AccuWeather forecasters are predicting a surge in tropical activity from September into October, breaking the silence across the ocean. The peak of the Atlantic hurricane season is around Sept. 10, but the majority of this year's storms and hurricanes could brew after the climatological peak.
"The season may end late this year, possibly well into November," Pastelok said, explaining that significant tropical activity could persist for an unusually long time, until nearly the official end of Atlantic hurricane season on Nov. 30.
In this GOES-16 geocolor image satellite image taken Thursday, Sept. 7, 2017, the eye of Hurricane Irma, center, is just north of the island of Hispaniola, with Hurricane Katia, left, in the Gulf of Mexico, and Hurricane Jose, right, in the Atlantic Ocean. (NOAA via AP)
Areas from Florida to the Carolinas are forecast to take the brunt of the activity this hurricane season, but people living near other areas along the Atlantic coast and the Gulf of Mexico shouldn't let their guard down. As has been the theme for the past few years, Pastelok said that there could be "one big system" that could make landfall in Texas or Louisiana.
Additionally, water temperatures have been well above average in the northern Gulf of Mexico, which could potentially help tropical systems in the Gulf gain strength as they approach land. Water temperatures typically need to be 80 to 82 F to fuel a hurricane, and as of Aug. 31, most of the water along the Gulf Coast of the U.S. was at least 86 F. Some beaches in Florida were reporting water temperatures just shy of 90 F, and water temperatures in Tampa Bay were around 92 F.
Not only can this unusually warm water fuel tropical systems, but also thunderstorms that erupt along the Gulf coast and northward into the Carolinas and Tennessee Valley. "Severe weather can get an extra boost, especially in the lower Mississippi Valley," Pastelok added.
The wet autumn predicted across the Southeast will put a significant dent in the drought conditions across the region with Pastelok saying that there is a "high" chance that most of the drought is erased. "It won't take much to get out of these drought conditions that are in place across the eastern Carolinas right now and parts of the lower and mid-Atlantic states," he added.
Downpours fueled by tropical moisture could also make it into coastal Texas, helping to ease drought worries in and around Houston and Corpus Christi.
October to bring major weather shift in Northeast, Midwest
The start of meteorological autumn is likely to feel more like summer for millions across the Midwest and Northeast as a persistent weather pattern continues to promote above-normal warmth across the region. But, big changes are expected to take place as the calendar flips to October.
Spells of dry weather paired with above-normal heat throughout the summer allowed pockets of drought to develop across New England, the interior mid-Atlantic and the Midwest.
For those looking forward to enjoying autumnal scenery, the widespread warmth could delay the peak of fall foliage in popular viewing areas. But, forecasters say the wait could be worth it this year as vibrant colors are likely to unfold on the hillsides across most of the Northeast, Great Lakes and the mid-Mississippi Valley, especially when compared to the foliage displays of 2021.
AccuWeather long-range forecasters believe that an increase in moisture will fuel rain across the Northeast and Midwest heading into autumn, helping to wash away drought concerns. As of late August, all of Rhode Island and parts of Connecticut and Massachusettes were experiencing extreme drought, according to the U.S. Drought Monitor. But, the rain will be a double-edged sword.
"The severe weather threat will pick up again," Pastelok said. "We do feel a late-season surge may not be as strong as last year when we had quite a bit of tornadic activity, but I still think there's going to be some and the peak month is October."
Some of the rain may not come in the form of severe thunderstorms, but rather from a named tropical system.
Last year, multiple tropical systems had significant impacts in the Northeast, including Tropical Storm Henri, which made landfall in Rhode Island, and Hurricane Ida, which caused unprecedented flooding in the New York City area and led to dozens of deaths as a tropical rainstorm. This year is also the 10-year anniversary of Superstorm Sandy, and another direct strike from a hurricane is not completely out of the question in the Northeast this fall.
"It is something to watch. But we just don't have the confidence yet to say that a major strike is going to hit the Northeast at this point," said Pastelok.
A person who eventually waded to a truck, moves amongst cars and other trucks that are stranded by high water Thursday, Sept 2, 2021, on the Major Deegan Expressway in Bronx borough of New York as high water left behind by Hurricane Ida still stands on the highway hours later. (AP Photo/Craig Ruttle)
As the summer warmth finally fades and the forest transforms from a sea of green to a palette of vibrant colors, folks across the Great Lakes and Northeast will experience the arrival of chilly air.
The first frost of the season could arrive one or two weeks earlier than normal across the Upper Midwest and upstate New York, which translates to late September and early October. However, Pastelok said that the early frost outlook does not pose a serious threat to agriculture during the autumn harvest.
The onset of cooler weather will be accompanied by an uptick in unsettled weather, including the chance for the first snowflakes since spring.
"There can be stormy periods for the eastern half of the nation with a primary storm track into the Great Lakes and Ohio Valley, where a mix of snow, rain and ice can occur," Pastelok said.
"In October, there can be one or two colder air masses that can be just cold enough to produce some snow showers in the interior higher elevations of the Northeast and across the Upper Midwest," Pastelok said. Most of the snow will be mainly limited to the typical mountain areas, which could help lay down a solid snowpack at some of the region's ski resorts.
Heat, drought to persist over Plains
While drought worries are quelled across New England, Midwest and Southeast, abnormally dry conditions will remain locked in place across most of the central U.S. throughout autumn. Exceptional drought conditions, the most severe classification of drought, were present in parts of Texas, Oklahoma, Kansas and Nebraska, according to the U.S. Drought Monitor.
"It's going to take a lot to break this drought," Pastelok explained. "The area is going to be hurting. I think going at least into the first half of fall, the moisture is just not going to be there."
One of the few sources of moisture will derive from the end of the North American monsoon, but most or all of the rain and thunderstorms associated with the monsoon will remain over the Four Corner states, which include Arizona, New Mexico, Utah and Colorado. Tropical-fueled downpours will also drench areas along and near the Texas coast, but will seldom extend farther inland to the regions experiencing the worst of the drought.
Thunderstorm activity over the central U.S. will increase in October and November delivering much-needed rain, but the bulk of the storms will likely be concentrated over the eastern Plains in eastern Kansas, Oklahoma, Missouri and Arkansas.
"October can be the most active month with potential tornadoes from the lower Mississippi Valley to the Ohio Valley," Pastelok warned.
The extended drought will be accompanied by lingering heat across most of the central U.S., especially during the first part of autumn.
Energy demand will remain elevated through September across Texas with more triple-digit temperatures possible in Dallas, San Antonio and Austin. Highs in the upper 90s to near 100 F are not unheard of in these cities during September, and that will not be a difficult temperature level for thermometers in the cities to reach amid excessively dry conditions.
Persistent warmth across the nation's heartland will delay the first frost, potentially by weeks, across much of the region.
Another factor behind the extended early-autumn heat can be traced back to the Gulf of Alaska. Pastelok said a persistent lower pressure in this area will influence the track that weather systems take as they traverse North America, and will "cut off any significant cold air from reaching the central and western U.S. too early" in the season.
The combination of extreme drought and long-lasting heat will have severe implications on the nation's agriculture -- some of which may be noticeable to Americans as they hit the grocery stores, even on top of current price hikes amid inflation.
"The drought has impacted commodities on a negative side, especially for the Plains," Pastelok said. "Most places have just given up as far as the wheat crop goes and the cotton crop is hurting a little bit," Pastelok explained. He added that some crops will fare better than others, including the spring wheat crop across North Dakota and Montana.
One of the biggest ramifications could be felt by cattle ranchers. Widespread heat and drought have already forced some ranchers to let go of their cattle. In 2020, beef exports generated $1.4 billion in revenue for ranchers in Kansas, a state that accounts for nearly 20% of all U.S. beef exports. Kansas is one state that has already reported major cattle losses amid extreme heat with more losses possible before the heat finally breaks.
"We're probably going to see [a] low supply of meat going into the fall and winter seasons based on the type of temperatures and heat and dryness we're seeing," Pastelok explained. "This can lead to higher prices, even after [recent] increases."
He added that extreme heat in the lower Mississippi Valley could lead to lower yields in soybean crops through September.
Drought to fuel another active wildfire season in Western US
Widespread, long-term drought has set the stage for another active wildfire season across most of the Western U.S., but the worst of the fires are expected to develop in different areas compared to 2021.
The North American monsoon has provided some drought relief across the Four Corners this summer, and it could have one last gasp before winding down during the second half of September. However, precipitation on a much larger scale will be needed to put a meaningful dent in the long-term drought that has sent water levels in reservoirs across the region down to record-low territory.
Most of the Western U.S. is bone dry amid widespread, extreme drought, so much of the interior West is a tinder box that just needs a single spark to start a fire that can evolve into a raging inferno.
Fire season is already underway with several notable wildfires burning throughout the summer months, including the Oak Fire that started in July near Yosemite National Park in California and the McKinney Fire which turned deadly in Northern California.
"We are predicting 68,000-72,000 fires and 8.6-8.9 million acres to burn," Pastelok explained. That forecast is well on its way to being realized with nearly 48,000 fires scorching 6.1 million acres burned as of Aug. 29. This is well ahead of the number of acres burned by the same point in the year in 2021.
Despite the projection of fires burning more land in 2022 than 2021, this fire season is likely to be much different than the last.
"Last year, we had incredible heat and dryness in the Northwest and western Canada early in the summer season that just kicked off the fire season," Pastelok said. It has been cooler with more moisture across much of the Northwest and western Canada this year, which will help to limit wildfire activity this autumn.
Instead, the focal point of the worst of the wildfires this year is predicted to be Southern California, where Pastelok said that "significant fires" could develop by late September into October.
"We are expecting a higher number of wildfires for Northern California, southern and eastern Oregon, Idaho, and northern Nevada," Pastelok added. The highest fire threat in these areas is expected in September through the first half of October.
The Pacific Northwest will be the first to turn the corner and head into the wet season with storms starting to deliver rain and high-elevation mountain snow as early as October. The arrival of these storms will signal the end of the fire season for most of Washington, Oregon and Idaho.
The arrival of storms in October and November will not only be good news for crews battling wildfires but also for skiers anxious to hit the slopes across the Intermountain West.
"I believe that there is going to be kind of a mix as far as the ski season goes in the Rockies in the West this year," Pastelok said.
For resorts in the Pacific Northwest, the start of the ski season may be slightly later than normal as the first storm systems to track across the region may not unload a plethora of snow, but once there is enough snow to build a solid base at ski resorts, the skiing season should be strong well into the winter.
Farther south in the Sierra, it could be a slow start for resorts that rely on natural snow. "I think they'll get on the normal pace, not the early pace that they saw the last couple of years," Pastelok said.
Snow should arrive in the higher elevations of the Rockies by mid-autumn. However, it will not be smooth sailing after the season's first flakes as warm weather could limit the accumulation at the base of the mountains until November.
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