100 millions Americans impacted by extreme weather across the country

On Friday 14th March an unseasonably strong blast of polar air pushed south towards Texas combined with a strong jet stream pushing Northeast across the Great Plains encouraging the air to lift. This resulted in a deep area of low pressure which encouraged strong thunderstorms to become strung out across the large swathe (running north to south) of western portions of the Deep South, and to the north-west -a potent late winter/early Spring snow event across parts of the Midwest. 

Ahead of this low pressure (further to the south-east) the cold/dry air quickly reduced the humidity across Oklahoma and parts of Texas and combined with the strong winds, created conditions for wildfires to spread, not too dissimilar to the mechanism for a final surge of fires across California earlier this year, before the rains arrived.  

However, when this occurs (a cold polar blast meeting a strong jet stream) further east due to the geography of the region and the position of the warm gulf waters to the SE, this can have consequences that ultimately impact people’s livelihoods. This pattern is known to create very unstable conditions and potentially enable severe thunderstorms or cells to develop as very warm, moist air from the Gulf is dragged north into the Deep South, fueling and energizing these storm systems, coinciding with the lengthening days and strengthening sun – so to speak.  

A combination of these factors continued over the weekend and the whole system slid eastwards moving the most intense weather away from Texas/Oklahoma all the way towards Florida by late Sunday/Monday. 100 million Americans have been impacted by extreme weather, with powerful winds of 80mph (130 km/h) expected across vast swaths of the country from the border with Canada, all the way to Texas, according to National Weather Service. 

The US Storm prediction center said that the fast-moving storms had the potential to spawn twisters with hailstones as large as baseballs with gusts of 100mph (160 kph) possible. 

High winds knocked out power to more than 250,000 homes and businesses in Texas, Arkansas, Missouri, Michigan, Illinois, Indiana and Mississippi, according to poweroutage.us as cited in CBS News. 

Five tornadoes were reported in Missouri on Friday, one of which was in the St Louis Area, with several buildings being damaged including a strip mall in Rolla, Missouri. 

The peak of this multi-day event was on an unseasonable warm Saturday afternoon across Mississippi, which sparked a series of strong storms which became tornadic. The ‘Tylertown, MS’ tornado has been estimated have been EF-4 on the EF (Enhanced Fujita scale (1-4) based upon early damage assessments, sadly causing multiple fatalities.    

Severe winds in the Northwest, which reached over 50mph, caused widespread delays and cancellations at Chicago O’Hare International Airport, with 764 flight delays and 48 cancellations on Saturday alone. United, American Airlines, Air France, Iberia, All Nippon, Icelandair, Southwest along with other airlines were all impacted by the delays.  

The airport is a major hub, connecting flights to other US cities including New York, Los Angeles, Dallas and Atlanta, so there will be knock-on impact at these airports from the delays. 

In the southern plains, the combination of strong winds and dry, warm weather had combined to raise the possibility of wildfires, triggering the evacuations of communities in Texas, Oklahoma. Kansas, Missouri and New Mexico, on Friday. 

Unfortunately, the wildfires did materialise over the weekend, with 70,000 acres being burnt in the state of Oklahoma according to the State’s Governor, Kevin Stitt. In addition, the National Weather Service issued blizzard warnings for parts of Western Minnesota and eastern Southern Dakota, with snow of up to 3 to 6 inches expected, and even as much as one foot of snow in places.