US weather: Winter SNOW returns to the north while the south bakes in 100F heat

A 100F heat blast is about to torch southern America while northern regions brace for snow.

Scorching heat has sparked warnings for wildfires in parts of the country while alerts for winter’s return are in force elsewhere.

It comes as violent storms scour the nation, with further torrential rain and damaging winds forecast into the final week of April.

Jim Dale, meteorologist for British Weather Services and US correspondent, said: “To the south of the country, very warm air is coming up from the Gulf of Mexico, and this could bring some very warm, dry conditions later in the week.

“In contrast, cooler conditions to the north will bring a north-south split across the country, and with competing air masses, you are going to get storm and thunderstorm activity.

“There is some decent heat brewing to the south, and with the humidity and higher temperatures moving into cooler air, this volatility is likely to continue into the final week of the month.”

Wintry downpours will cap a fortnight of severe weather which has stirred up fierce storms and almost 100 reported tornadoes.

Towering storm clouds building in the unstable atmosphere could trigger ‘supercell’ thunderstorms in parts – unusually aggressive storms lasting hours.

Torrential downpours sweeping across the country prompted the National Weather Service (NOAA) to issue flood advisories across Texas, Louisiana, Mississippi and Arkansas.

Separate winter weather alerts are in force in Montana and Wyoming, while further south, dry winds threaten to drive wildfires.

A NOAA spokesperson said: “A cold front sweeping across the north-central US will bring additional heavy snow along the mountains and foothills of the northern Rockies.

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“Farther west, colder temperatures behind a cold front moving out of eastern Montana will support snow over much of the northern Rockies and into the foothill locations, especially over northern Wyoming.

“For the Southwest, warmer temperatures into the 80Fs and 90sf will be common under fair conditions, and into south Texas, temperatures may climb to near 100F.”

Volatile weather has been driven by unstable air masses battling astride a powerful jet stream.

The NOAA has logged more than 900 reports of severe weather since the start of the month, including thunder, wind and golf-ball sized hailstones.

Thunderstorms will move eastwards ahead of the weekend as low pressure is steered across the country on the jet.

Weather Channel meteorologist Jonathan Erdman said: “Another round of severe storms might erupt further south on Thursday as a new low-pressure system arrives from Texas into the Ohio Valley.

“Wind damage and hail appear to be the primary threats.”

A spokesman added: “Damaging winds and isolated tornadoes are possible, while storms could produce very large hail.

“The threat moves east on Thursday as damaging winds and hail remain the main threat.”

Rising temperatures, low humidity and gusty winds have sparked warnings for wildfires across south-eastern Colorado.

Ground conditions will be ‘favourable for rapid rates of fire growth and spread’, according to the NOAA.

A spokesman said: “A combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behaviour.”