Central U.S. dealing with blizzard, tornado threat and fire concerns

WEATHER NEWS: Central U.S. dealing with blizzard, tornado threat and fire concerns


Parts of the central United States have dealt with dangerous thunderstorms and tornadoes Tuesday, with more to come through Wednesday. This is all happening while a potentially historic blizzard rages over the Dakotas and fire weather concerns rage on the High Plains.

Several tornadoes appeared on Tuesday evening in Iowa and Texas, where potentially record-breaking hail was also reported. The Weather Service will make assessments in days to come, although some areas appear to show significant damage.

The National Weather Service Storm Prediction Center has issued level 4 out of 5 “moderate risk” of severe weatherand for a large part of the Mississippi Valley on Wednesday, citing “the potential for strong tornadoes and very large hail.”

Great Plains could see its most significant drought in a decade

The insurgence of dry air behind the storm will parch the High Plains, bringing “extremely critical” fire weather. Meanwhile, the McBride fire started near Ruidoso, New Mexico on Tuesday afternoon, consuming around 150 structures and homes by the evening.

On the storm’s cold side, blizzard-like conditions are already underway in Bismarck. Records may fall as a blizzard delivers what the Weather Service is referring to as an “extreme impact” event in North Dakota. Bismarck could close in on a foot and a half of snow; if the city surpasses the record of 17.8 inches set in 2013, they’ll snag their snowiest April storm ever observed.

Tornado watches were in effect into Tuesday night for much of northern Iowa and surrounds, as well as a chunk of central Texas eastward into Louisiana.

The evening opened with a large and destructive tornado that touched down in Texas near the town of Salado. That storm also produced massive hailstones, perhaps to near 6 inches in length.

The severe weather in Texas was shortly followed up by several rotating thunderstorms intensifying over Iowa. One prolific storm rapidly moved across northern portions of the state while dropping several twisters.

Going into the night, storms are tending to form up into lines as additional activity blows up along the cold front plowing into the Midwest. Damaging winds may be the main threat through Wednesday morning, but at least isolated tornado potential also remains.

The action got underway Monday. In west-central Arkansas, baseball-size hail was reported Monday afternoon in Franklin County, with at least one instance of softball-size hail in New Blaine, a little west of the midway point between Little Rock and Fort Smith. Several tornadoes also were observed, including one that prompted a dire tornado emergency around the Little Rock Air Force Base. So far, no injuries have been reported.

On Tuesday, the primary impetus for storms will be a sharpening dryline, or the leading edge of arid air from the Desert Southwest as it encroaches into gulf moisture farther east.

During the day, moisture will rapidly stream north with an advancing warm front that makes it all the way into Minnesota and Wisconsin by evening. The dryline will position itself near Interstate 35 from north-central Texas through Oklahoma and Kansas while stretching toward Omaha.

There are two zones of heightened risk drawn by the Storm Prediction Center — one that covers northeast Kansas through most of Iowa, where a level 4 of 5 moderate risk was issued this morning, and the other between Dallas and Waco. Between, there’s still a level 2 out of 5 slight risk for isolated severe thunderstorms, but a “cap,” or a lid of warm air about a mile above the ground, will tamp down pockets of surface air that try to rise and form storms.

The Storm Prediction Center notes that if storms form, they’ll do so in a “potentially volatile severe thunderstorm environment,” but coverage in most locales will be sparse until overnight, when a line of storms forms on an advancing cold front.

In Texas, it might be a bit hotter at ground level, leading to more instability, or “juice,” for storms. To the north across the Corn Belt, greater proximity to an approaching upper-air disturbance means falling temperatures aloft, which will foster greater ascent, or rising motion, that can help thunderstorms bloom.

Any storms that break the cap during the day are likely to erupt explosively and become supercell thunderstorms capable of producing damaging winds, large hail and tornadoes. A strong tornado or two are possible, given the wind dynamics present in the atmosphere.

On Wednesday, an energetic dip in the upper-level jet stream will shift closer to a cold front and dryline merging into one. Meanwhile, an enormous warm sector, or region of mildness and humidity advecting northward ahead of approaching low pressure, will expose a wide swath of the Mississippi Valley region to dangerous storms.

The Tuesday afternoon update from the Storm Prediction Center for Wednesday upgraded a large portion of the Mississippi Valley to a level 4 of 5 moderate risk, stating “strong tornadoes, very large hail, and significant damaging gusts are all likely with the most intense storms.”

Hugging the river, the moderate risk runs from northern Louisiana to southern Illinois and Indiana, including locations like Pine Bluff, Ark., Memphis, Tenn., and Evansville, Ind.

Around the moderate risk, a large level 3 of 5 enhanced risk runs from central Louisiana to just south of Chicago. Cities included in the enhanced risk include St. Louis, Mo.; Little Rock, Ark.; and Jackson, Miss. Broader marginal and slight risks surround the enhanced strip. Some severe weather is still possible in the zone of slight risk.

A broken squall line with embedded circulations known as a QLCS, or quasi-linear convective system, will form along the cold front from the Mid-Mississippi Valley to the lower Ohio River Valley. The broken line will likely contain numerous instances of damaging straight-line winds in excess of 60 mph and the potential for tornadoes. Additionally, any storms that develop ahead of the line may contain any and all severe weather hazards.

In the Lower Mississippi Valley, including portions of Arkansas, Mississippi and Louisiana, a strong tornado threat is anticipated late in the day as rotating supercell thunderstorms likely dot the region.

Some severe weather risk may make it to the East Coast and Southeast on Thursday before more tranquil weather builds in for the weekend.

Low pressure ejecting out of the Colorado Front Range will pass through the Nebraska Sandhills en route to northern Minnesota into Wednesday. Moisture wrapping northwest around the low will fall into frigid air dragged south in the system’s wake, producing hefty snow totals that could flirt with records.

The National Weather Service is forecasting up to 30 inches of snowfall, with widespread totals of 18 to 24 inches in most of central and western North Dakota. Nearly the entire state is under a blizzard warning.

Snow will increase in coverage and intensity throughout Tuesday as it exits out of Wyoming and Montana and consolidates. Winds on the backside of the low will increase out of the west-northwest, gusting between 40 and 50 mph. The strong winds will couple with falling snow to bring visibilities below a quarter mile and “very difficult to impossible” travel.

Heavy snow will also fall in eastern Montana and northwest Minnesota through Wednesday morning. The system will exit into Manitoba and Ontario on Wednesday; stateside, the system will end in the form of some renegade light snow showers pinwheeling down from Canada.

The same low pressure system brewing severe and winter weather will also swirl a tongue of exceptionally dry air east into the southern and central High Plains. Ongoing drought combined with an influx of parched air will further desiccate the landscape, contributing to the risk of wildfires.

Adding fuel to the fire, so to speak, will be increasing winds that will gust over 50 mph Tuesday. That, coupled with recent scant rainfall, will make for an environment where any spark could become a major fire.

“An outbreak of dangerous wildfire conditions is likely across the southern and central High Plains today,” wrote the National Weather Service.

About 1.6 million people in west Texas, the Texas and Oklahoma Panhandles and southwest Kansas are under a top-tier “extremely critical” wildfire risk, which includes Garden City and Liberal, Kan., Guymon, Okla., and Amarillo, Lubbock and Midland, Tex.

Kasha Patel contributed to this report.





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