Meteorologist Ryan Hall says an extraordinary stretch of rainfall across the United States is moving east into the Ohio Valley, Tennessee and the Deep South, while a series of cold fronts begins to bring a more lasting autumn pattern to much of the central and eastern country.
In a forecast posted on his channel Ryan Hall, Y’all, Hall said the broader storm pattern is tied in part to the remnants of Hurricane Polo, which moved north from the Pacific after weakening over Mexico and helped feed a large plume of moisture into the central United States.
Hall estimated that roughly 69 trillion gallons of water could fall over about 10 days, enough, he said, to temporarily lower global ocean depth by less than a millimeter as that water sits over land instead of in the sea.
“There’s so much rain falling on this country right now that the ocean is actually getting a little bit lower,” Hall said.
Polo’s Moisture Keeps Moving East
Hall explained that Polo’s remnants were pulled north by a dip in the jet stream, helping support heavy rain across the central Plains before the moisture began shifting farther east.
The system has already produced extreme rainfall in Nebraska and severe thunderstorms farther south, but from Friday onward, Hall said the main focus moves toward the Ohio Valley, Tennessee and eventually the Southeast.
Indianapolis, Louisville and Cincinnati are among the places he expects to see a notable round of rain on Friday as the leading cold front pushes through.
By Friday night, that moisture should spread into Tennessee, where Nashville is finally expected to receive measurable rainfall after what Hall described as an exceptionally dry stretch.
He said Nashville went through September without a measurable drop of rain, something he said had not happened there since 1963.
That makes the incoming rain welcome, although the amount will still vary considerably from place to place.
Drought Relief Will Be Uneven
Hall said Tennessee and Kentucky are likely to receive roughly half an inch to 1.5 inches from the first wave, with Nashville expected to come in a little above an inch.
That should help, but he cautioned that it will not be enough by itself to erase the drought that has expanded quickly across the region.
Hall said the drought footprint in Tennessee had grown dramatically in recent weeks, meaning one round of rain cannot make up for a prolonged dry period.
Farther south, the outlook becomes wetter.
Birmingham, Atlanta and Charlotte could each receive roughly 2 to 3 inches, which would provide more meaningful relief where soils have been dry.
The tradeoff is that once the front reaches the Gulf Coast, it is expected to slow or stall, allowing moisture to keep feeding into the same areas for a longer period.
That is where helpful rain can become excessive rain.
Gulf Coast Could See 5 To 8 Inches
Hall said the heaviest totals over the coming week could stretch from New Orleans through Mobile, Pensacola and Tallahassee, where 5 to 8 inches may fall, with isolated locations potentially exceeding that.
He described the setup as the kind of rain that can go beyond drought relief and start creating street flooding.
The distinction matters because several parts of the South have been waiting for rain for weeks, but a stalled boundary can deliver too much of it in too short a time.
Hall said persistent Gulf moisture will keep feeding showers and thunderstorms into the North Gulf Coast, which means communities there could see repeated rounds rather than one clean frontal passage.
That kind of pattern often creates a sharp contrast over relatively short distances, with some towns seeing a manageable soaking while nearby areas deal with drainage problems or flash flooding.
Hall’s main message was that the rain is finally arriving for many people who have been asking for it, but it will not be distributed evenly or gently.
Hall Says The Heat Dome Is Finished
The other major change in the forecast is temperature.
Hall said the prolonged late-season heat that affected much of the central and eastern United States is finally breaking down, with a much cooler pattern taking over through the weekend and early next week.
Louisville, Cincinnati and Indianapolis are all expected to see temperature drops of roughly 20 degrees compared with the recent heat.
Nashville should fall from the mid-90s into the upper 70s, while Washington, D.C., could move from near 90 degrees to the 60s by Sunday.
Cooler air should also reach Atlanta and the Carolinas by Sunday and Monday.
Hall said he reviewed multiple model runs for Louisville and Nashville and found very little support for a return to 90-degree heat over the next two weeks.
That does not mean every day will feel cold, but it does suggest the persistent summer-like pattern is finally losing its grip.
A Second Front Brings Frost Risk
Behind the first system, Hall said another cold front is expected to arrive Sunday night and bring some of the coolest air since spring to the Great Lakes and Northeast.
By Tuesday, highs could remain in the 60s from Chicago through Pittsburgh, while New York City may struggle to get much above 60.
The colder mornings will be more noticeable.
Hall said Cincinnati and Indianapolis could wake up in the low 40s, with Pittsburgh and Detroit near 40 as well.
Parts of Michigan, Ohio, Pennsylvania and the interior Northeast may see their first frost of the season, while some colder locations in northern Michigan and Vermont could dip into the 20s.
That is a meaningful seasonal shift after weeks of unusual warmth.
Hall expects temperatures to rebound somewhat later next week, with 70s becoming common again and a few places possibly reaching the 80s, but he does not expect anything resembling the previous heat dome.
A Third Cold Front May Arrive Around October 12
Hall is also watching a third front later in the month, around October 12, although he stressed that model agreement is not yet strong enough to treat the exact outcome as certain.
One of the major models shows a considerably colder push, potentially bringing the first 30s of the season to Cincinnati, Indianapolis and possibly Louisville and St. Louis.
That same scenario would keep highs in the 50s around Chicago and Detroit and could bring Nashville down into the 40s.
The other major model is less aggressive, showing a cooler pattern without the same widespread frost risk.
Hall called the first widespread 30s in the Ohio Valley a “maybe” for now, but said he is much more confident that October is entering a substantially cooler overall pattern.
Hall also pointed to another unusual part of the current weather setup: the Atlantic hurricane season has remained extremely quiet even as the Pacific has produced multiple powerful hurricanes.
He said the Atlantic made it through September without a hurricane, which he described as an exceptionally rare occurrence.
By contrast, the Pacific has already produced several hurricanes, including multiple Category 5 storms, and remnants from those systems have helped feed moisture into the United States.
Hall attributed much of that contrast to El Niño and said the Atlantic may continue struggling to produce an organized hurricane in the near term.
For now, however, the more immediate concern is inland rainfall rather than tropical development along the East Coast.
More Rain And Cooler Air Define The Next Phase
Hall’s forecast suggests that the first full week of October will be defined less by heat and more by the interaction between lingering tropical moisture and repeated cold fronts.
The Ohio Valley and Tennessee will finally receive needed rain, the Deep South will see heavier totals, and the Gulf Coast could receive enough water to create flooding problems rather than simply drought relief.
At the same time, much of the Midwest, Northeast and eventually the Southeast should move into a cooler and more seasonable pattern, with frost becoming possible in parts of the northern tier early next week.
The remarkable part of the setup, Hall said, is the sheer amount of water involved.
His estimate of roughly 69 trillion gallons over about 10 days is large enough that some of that water is, for the moment, sitting over the United States instead of the ocean, illustrating just how much moisture this pattern is carrying as it continues east.
Growing up in the Pacific Northwest, John developed a love for the great outdoors early on. With years of experience as a wilderness guide, he’s navigated rugged terrains and unpredictable weather patterns. John is also an avid hunter and fisherman who believes in sustainable living. His focus on practical survival skills, from building shelters to purifying water, reflects his passion for preparedness. When he’s not out in the wild, you can find him sharing his knowledge through writing, hoping to inspire others to embrace self-reliance.
