Meteorologist Ryan Hall says a major pattern change is taking over the United States this week, bringing dangerous storms and flash flooding to parts of Texas and the Gulf Coast, unusual heat to the northern Plains, and a much calmer stretch for some areas in the Northeast.
In a forecast on his YouTube channel Ryan Hall, Y’all, Hall said a sprawling omega block is expected to lock into place later this week, creating a stubborn weather pattern that could hold extremes in place from coast to coast for days.
“A massive pattern shift” is on the horizon, Hall said, describing a setup that may scramble the forecast and leave different regions stuck under very different weather problems.
That is the strange part of this pattern. One part of the country may be dealing with rapidly rising water, while another bakes under dry heat, and another gets the kind of pleasant late-May weather people wait all year for.
Texas Faces A Rough Severe Weather Setup
Hall said Tuesday will be a serious day for parts of West Texas, especially around Midland, Odessa, and Andrews.
He warned that the Permian Basin is facing a setup that could produce dangerous storms during the late afternoon and evening hours. Hall said more than half a million people may be inside the risk area, with the strongest concern south of Lamesa.
The main window he highlighted is from 4 p.m. to 9 p.m., which means storms could affect the evening commute and the hours just after dinner.
Hall said temperatures may stay in the 70s and 80s because of cloud cover, but the atmosphere will still have plenty of fuel for storms. A wave of energy moving out of the Pacific Northwest is expected to crash into easterly winds pushing rich Gulf moisture up against higher terrain.
That combination, he said, could create classic supercell conditions.
Hall pointed to storm energy near 2,000 joules per kilogram and 30 to 40 knots of wind shear. In simpler terms, that means the atmosphere may have both the energy and the turning winds needed for strong rotating storms.
“These are going to start off as discrete supercells capable of dropping hen-egg-sized hail,” Hall said.
He explained that hail larger than 2 inches can shatter windshields and even total vehicles left outdoors. Later in the evening, as storms cluster together, they could produce 60 to 70 mph wind gusts, strong enough to knock out power and damage roofs.
Tornado And Hail Concerns Along Key Corridors
Hall said the tornado threat is also worth watching in West Texas.
He was especially concerned about the I-20 corridor between Pecos and Midland, as well as the more remote I-10 corridor farther south. Before the storms merge into a line, he said, the supercells may have their best chance to produce tornadoes and very large hail.
That detail matters because the early storm mode may be more dangerous than the later one. A line of storms can still be damaging, but isolated supercells can be more capable of producing giant hail and tornadoes before they become messy or merge together.
Hall urged people driving along I-10 or other exposed routes to watch radar closely and avoid trying to ride out storms in bad spots.
He said people should not rely on hiding under overpasses to protect their vehicles. Instead, he said they should reroute, change plans, get lunch, or simply let the storms pass.
That kind of advice sounds ordinary, but it is useful. Severe weather safety is often not about one dramatic decision. It is about making small, early choices before the storm is already on top of you.
Flash Flooding Becomes The Main Event
While severe storms are a major concern, Hall said the biggest threat in Texas and along the Gulf Coast may be flooding.
“The actual storms are just the opening act over here in Texas,” Hall said. “The main event tomorrow is going to be the water.”
He warned of a life-threatening flash flooding threat aimed at the Gulf Coast, putting millions of people at risk of rapidly rising water.
Hall highlighted two main areas of concern: the Texas Hill Country near San Antonio and the central Gulf Coast from Biloxi to Mobile. Along the Gulf Coast, downpours are expected to begin during the afternoon. In Texas, the flood threat becomes more concerning overnight from Tuesday into Wednesday.
Hall said the peak Texas flood window may run from 10 p.m. Tuesday to 6 a.m. Wednesday, which makes the risk more dangerous because people may be asleep when warnings are issued.
The storm system moving east, he said, will act like a giant atmospheric vacuum, pulling deep tropical moisture off the Gulf. Hall said the atmosphere will hold 1.5 to 2 times the normal amount of moisture, creating storms that can dump rain very efficiently.
He warned that some areas could see widespread 2 to 4 inches of rain, with isolated places topping 5 inches. That rain may fall on ground already saturated from recent storms.
When storms train over the same areas for hours, Hall said, water can rise quickly in low-lying spots, intersections, creeks, streams, and neighborhoods with poor drainage.
Overnight Flooding Is A Special Danger
Hall spent extra time warning people in Texas not to underestimate the overnight flood threat.
He said low-level moisture in the Hill Country could act like a fire hose, feeding repeated thunderstorms over the same places. That can create a nocturnal flood threat, one of the most dangerous kinds because people may not see the water until it is already too late.
Hall urged viewers to make sure their phones can wake them up for flash flood warnings.
“Make sure your phone absolutely will not shut up until you are getting to higher ground,” Hall said.
He also warned people not to drive around during flooding. A few inches of fast-moving water can sweep away even larger vehicles, including SUVs and trucks.
That warning is worth repeating because flash flooding often kills people in vehicles. It is easy to misjudge water on a dark road, especially when the pavement disappears under muddy flow. By the time a driver knows the water is too deep, the vehicle may already be floating.
Hall said the water problem will not simply disappear after Tuesday. Instead, it will shift east.
By Wednesday, he said, eastern Texas, the Ark-La-Tex region, and the lower Mississippi Valley may face another round of heavy rain. Southeast Texas could redevelop storms that make the midweek commute messy, and the moisture plume may remain near record levels across the Deep South.
Hall said areas from Texas into Mississippi, Alabama, Florida, and Georgia should watch any new downpours closely, especially where recent rain has left the ground soaked.
Northern Plains Face Unseasonable Heat
While the southern United States deals with heavy rain, Hall said the Dakotas and the upper Midwest will face a very different problem: heat.
He said an unseasonably hot air mass will surge into the northern Plains, with temperatures running 15 to 20 degrees above average. Near-record highs of 90 to 95 degrees are possible across the Dakotas, with humidity falling into the teens.
Hall said high pressure building above the region will act like a lid, trapping heat at the surface and baking the ground.
The heat could also speed up mountain snowmelt, especially around Montana and Wyoming, where rivers and streams may need to be watched even without heavy rain.
This is one of the more unusual parts of the forecast. Flooding can come from rain, but it can also come from heat melting snow too quickly. The result may be the same for people near rivers: rising water, changing conditions, and a need to pay attention.
Hall said outdoor workers in the northern Plains should be careful because the heat is arriving before many people are ready for it.
“We’re pretty much skipping right over spring up here,” he said.
The Omega Block Could Lock The Pattern In Place
Hall said the larger reason for these extremes is an omega block, a weather pattern that can freeze conditions in place for several days.
Starting Tuesday and especially by Thursday, May 28, he said a huge dome of high pressure may build over the central and north-central United States into Canada. That high pressure will be sandwiched between two deeper storm systems near the coasts, creating the shape that gives the omega block its name.
If the setup holds, Hall said, the northern tier of the country will sit under warm, dry air, while the southern United States remains stuck under an active storm track.
A strong high pressure system near Hudson Bay may pump dry air into the Great Lakes, helping keep heavier moisture locked farther south.
That means the upper Midwest could see several sunny, hot days running 10 to 20 degrees above normal, while the Deep South deals with repeated rounds of heavy thunderstorms.
For Texas, Hall said that may cause problems for outdoor events, including the opening round of the Charles Schwab Challenge on Thursday, where serious weather delays and soggy conditions could be possible.
The omega block is fascinating because it can make weather feel stuck. Instead of systems moving cleanly across the map, the same general pattern can repeat day after day. That is good news if you are under calm skies, but bad news if you are under the storm track.
A Beautiful Stretch For The Northeast
Hall said the forecast is not all bad.
For Tuesday and Wednesday, he said the Northeast and Mid-Atlantic may see some of the nicest weather in the country. Areas such as Manchester, New Hampshire, and Rutland, Vermont, could enjoy mostly clear skies, low rain chances, and crisp dew points in the 50s.
Temperatures may run a bit warm, reaching the low to mid-80s, but Hall described the setup as beautiful rather than perfect.
He said baseball fans heading to Fenway Park for the Braves and Red Sox, or to Citi Field for the Mets, could not ask for much better baseball weather.
Beaches may also do well, with ocean swells dropping to about 3 feet, a gentle southwest breeze under 10 mph, and afternoon highs near 80.
For a country split between storms, floods, and heat, that quiet pocket stands out.
Hall’s forecast shows a nation heading into a strange late-May pattern, where weather extremes may sit side by side. Texas and the Gulf Coast may be watching the sky and the water. The northern Plains may be jumping into summer heat. The Northeast may get a rare stretch of near-ideal outdoor weather.
That is the nature of this pattern, according to Hall: locked-in, uneven, and powerful enough to make one part of the country feel like summer, another feel storm-weary, and another feel almost lucky.
Mark grew up in the heart of Texas, where tornadoes and extreme weather were a part of life. His early experiences sparked a fascination with emergency preparedness and homesteading. A father of three, Mark is dedicated to teaching families how to be self-sufficient, with a focus on food storage, DIY projects, and energy independence. His writing empowers everyday people to take small steps toward greater self-reliance without feeling overwhelmed.
