Stormy weather may be brewing in central states. Here’s where there’s most risk.

Meteorological spring is here, and severe weather is about to ramp up markedly. Wednesday through Saturday will feature the potential for severe thunderstorms – particularly in central states – and there is even the chance of a couple of tornadoes.

The National Weather Service’s Storm Prediction Center has already highlighted four consecutive days as having a severe storm risk. The most widespread and potentially significant storms are expected Friday, some of which may be rotating supercells.

March is typically when we see a sudden ramp-up of storminess as the retreating cold of winter clashes with insurgences of warm, humid springtime air from the gulf. By April, we are in the thick of tornado season, which peaks in May and continues strong into June.

Typically, the Deep South sees its nastiest weather early in the season. Then storms spread farther north into the southern and central Plains and eventually the High Plains and Rockies by the start of meteorological summer in June.

The upcoming pattern

The jet stream – a river of swiftly moving winds in the atmosphere – is about to dip over the western United States. That allows frigid air aloft to spill south over the Rockies. Pockets of cold air, low pressure and spin pinch off from this blob of upper-level cold; we call each one a shortwave.

Individual shortwaves will eject east toward the Plains and Midwest. Ahead of them, warm, humid gulf air wafting northward will make for instability, or thunderstorm fuel. Each approaching shortwave encourages the air ahead of it to rise, generating thunderstorms. And with strong jet stream winds aloft, there is plenty of wind energy to tap into. That’s why some of the storms could produce damaging gusts as they mix momentum to the surface. A few tornadoes are possible where changing winds with height help storms to rotate.

Low pressure over Missouri is dragging a cold front east into a moisture-rich air mass. That will help another round of storms to blossom by midafternoon. Initial discrete (isolated) storms will pose the threat of hail up to ping-pong-ball size; there is a marginal, but nonzero, risk of an isolated tornado.

By mid-evening, thunderstorms will likely merge into windy lines and clusters as they push east-northeast into the Ozarks.

ThursdayA slight (Level 2 out of 5) risk encapsulates West Texas, including Midland, Lubbock, Amarillo and the Panhandle; western Oklahoma, including Lawton, Elk City and Woodward; and southwest Kansas, including Liberal.

Low pressure in southeast Colorado will drag a dryline eastward, representing where dry, desert air impinges on moist gulf air. That may make for a few late-day supercells after 4 p.m. or 5 p.m. with some risk for hen-egg-size hail, damaging gusts or a couple of tornadoes. Confidence is increasing in a few supercells sprouting in the corridor from Amarillo, Texas, to Altus, Oklahoma, likely with hail and a tornado or two. After 10 p.m., they may merge into clusters or lines and shift northeast, perhaps reaching Oklahoma City in a weakened state overnight.

A caveat is the mid-level flow; about a mile up, winds are out of the south, parallel to the dryline. That means there will not be steering winds to push storms off the dryline. The result? Storms may move along it and merge into clusters after a couple of hours, reducing the tornado threat but increasing the risk of damaging winds.

FridayAn enhanced (Level 3 out of 5) risk has already been drawn by the Storm Prediction Center; it stretches from Missouri’s St. Joseph and Kansas City to Tulsa, Oklahoma City and Ardmore in Oklahoma. A broader slight (Level 2 out of 5) risk spans from Chicago and La Crosse, Wisconsin, all the way to Dallas, Waco and Abilene in Texas; and also includes Springfield, Missouri; Wichita, Kansas;, Omaha and Lincoln, Nebraska; and Springfield, Illinois.

That covers a large amount of area. Low pressure over Sioux Falls, South Dakota, will draw an expansive warm sector northwards meaning there is a broad area where storms can form ahead of an approaching frontal system. And with changing winds with height associated with a robust jet stream dip approaching, confidence is increasing in the potential for some tornadic supercells.

“This will support a threat for supercells with strong tornadoes,” the Storm Prediction Center wrote.

It’s also probable that storms will continue into the first half of the overnight, feeding off a low-level jet stream (strong southerly winds a mile above the ground) that will ramp up around nightfall. Storms may also move repeatedly over the same areas, dumping heavy rain.

SaturdayThat same front will probably get hung up along Interstate 30 from Dallas to Texarkana. It may touch off a few additional storms with wind or hail, but confidence in the position of the front, and subsequently any expected hazards, is low.

“Although an isolated severe threat will be likely in some areas, uncertainty is considerable concerning the area with the greatest severe threat,” the Storm Prediction Center wrote.