A top-end storm is explosively deepening in the open Atlantic right now. Central pressure should drop below 930 hPa.
The jet stream dynamics are jaw-dropping.
The storm development is linked back to a baroclinic zone over the Southern States. Cold air flooded the USA with strong thermal contrast (very warm to the south).
A beautiful but powerful storm.
The jet stream interacting with the developing surface cyclone is crucial for such a powerful storm.
The coincidence of the surface cyclone under the 'right entrance' then 'left exit' greatly enhances the cyclone development
'Explosive cyclogensis' is an actual term used in meteorology. Others may call this a 'weather bomb'.
For a cyclone to be defined as a 'weather bomb', the central pressure must drop by at least 24 hPa in 24 hours.
This storm drops a whopping ~48 hPa in 24 hours.
The storm is massive (spatially). Mid-latitude cyclones like this are far larger in size compared to hurricanes for example. This storm is dragging a lot of cold air east to the south of Greenland.
More unprecedented severe weather is unfolding in the USA as we speak.
The warmth racing north through areas to the east of the Rockies likely to break many December records. We are talking about 30-40°F warmer than average.
The warmth is only a part of the story...
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The temperature & contrast is incredible. Watch how the warm/tropical feed is blasted north and east (all the way into Canada) as low pressure ejects from the Rockies.
This is a seriously fast-moving system. A top-end wind storm is unfolding...
As the low pressure rapidly deepens, extreme wind gusts will quickly spread from the Rockies into the mid-west.
Dangerous conditions expected with 60-80 mph gusts widely, but locally 100 mph possible. Wind damage, blowing dust & fire danger are among the hazards.
Heart-wrenching news coming from the USA as extreme long-track & violent tornado leaves a path of devastation crossing *four* states.
A particularly severe setup for December fuelled by insane warmth & moisture transport under a vigorous short-wave trough.
This latest pulse of heat from the south is breaking December heat records, more to come on that.
The unfortunate combination with strong upper-level winds and high instability throughout the atmosphere meant the atmosphere was 'perfect' for extreme thunderstorms & tornadoes.
The pulse of heat from the tropics is truly remarkable. We are looking at some places east of the Rockies recording temperature values 15-20°C (20-35°F) above seasonal average.