This is an animation which vividly illustrates how a tropical cyclone transitions into an extratropical cyclone in the northeast Atlantic. Hurricane Ophelia, a rare category-3 hurricane in the northeast Atlantic with a symmetric warm core and a well-defined eye (beginning of video) interacted with a strong cold front (the long white band approaching from the north and northwest) and was transformed into an asymmetric mid-latitude cyclone before hitting Ireland earlier today. Cold air behind the front was injected and wrapped around the western quadrant of the storm while dry air from the stratosphere (red tones) sinks into and mixes with air in the troposphere as the extratropical transition occurs. The storm continues to head northeast towards northern Scotland and eventually Norway as it gradually weakens! The imagery shown in this animation is a known as an RGB composite.
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