Hurricane Patricia has been a rather unusual hurricane. It developed very rapidly out of a pool of typical, general ITCZ or Tropical upper level cloud area not far from Belize, in the Pacific off Guatamala.
A Week ago, last Saturday, there were several heavy swell-up areas, the one in the Gulf they were saying might become a storm, just dispersed. They really did not appear to have a clue where the low pressure centre was. turned out to be over Belize for days. But similar swell-ups continued to develop in the Pacific, along the Guatamala coast. This is very normal, many evenings, last Saturday was no exception.
That area continued to reduce and increase in ITCZ type activity. But on Tuesday, as the activity over Belize was dying down, the area in the Pacific, was just starting a little rotation, not obvious at first, but by Wednesday 21, the weather people had seen it was developing, and got dragged along to the west with the general Tropical weather band or Monsoon Trough, but in doing so, it started to get carried slightly northwards, so the Coriolis effect started to act, which causes surface winds going in to the Low pressure centre, to rotate anticlockwise in the Northern Hemisphere.
Tropical Storms tend to curl upwards, this one got caught by the regular high level Pacific winds that typically go over central Mexico, which caused this Storm to turn due north which resulted in very rapid intensification, as the Coriolis effect really kicked in, and joined by more wet air from the Pacific, helping it to become a Cat.5 hurricane. One of the fastest developing hurricanes ever, and one of the strongest on record.
What was causing some confusion is that from the overhead Satellite pictures, it might have looked as if the hurricane was rotating clockwise. The Coriolis effect causes air rushing in towards the centre, that is near the sea surface, to rotate anti-clocwise, but the outpourings above the hurricane that are now going in the opposite direction, that is outwards, will rotate in the opposite direction, that is clockwise. This is what can be seen from the Satellite pictures.
In this particular hurricane, the north side of the top of the hurricane was being caught by the upper level jet stream, making for fast movement over Mexico and southern Texas, meanwhile the southern side of the hurricane, was still being fuelled by typical Tropical wet air coming from the east
Worth reading the Dr. Jeff Masters' Blog Stunning, Historic, Mind-Boggling, and Catastrophic: Hurricane Patricia Hits 200 mph " Incredibly strong Hurricane Patricia is barreling ashore on the Southwest coast of Mexico near La Manzanilla as a Category 5 storm. At 5 pm EDT Friday, NHC put Patricia's intensity at 190 mph winds. Early on Friday morning, Patricia reached a remarkable intensity of 200 mph sustained winds, which the storm maintained for 12 hours. These are the highest reliably-measured surface winds on record for a tropical cyclone, anywhere on the Earth. At 2:30 pm Friday afternoon, October 23, 2015, a NOAA hurricane hunter aircraft measured a central pressure of 879 mb--the lowest pressure ever measured in a hurricane in the Western Hemisphere. "..... and see his blog for more.