Thread by @althecat

Hurricane Pamela's weird trajectory is because she's running in to a massive wind field at Jet-stream level that is blowing in off the Pacific. This appears to be accelerating her strengthening.

Here we see Pamela's development over the past 24 hours. To her north you see high level clouds blowing in from the South East over the Tijuana Peninsula - and blowing the storm over the great lakes away to the north east.

And in this closeup we see #PAMELA's explosive convective development over that 24 hour period. As the sun rises she's looking a little ragged but huge even though the sheer on her northern side is massive, with massive outflow plume already extending well beyond Texas.

Here's the beginning and end of the latest NHC Discussion.

"dropsonde wind data from an earlier AFR recon. aircraft indicate the vortex column from the surface to at least the 700-mb level was vertically aligned with no tilt evident."

This means that the wind to #Pamela's north is not blowing her apart. And the warning bit at the end signifies massive damage potential on the Mexican coast where she has already started to run into high mountains.

This animation shows #PAMELA just for the past three hours. You can see the dry air that she is dragging in from the north west revealing the edge of her convective core, which has no eye, and seems unlikely to develop one.

Here we see #PAMELA over the past six hours. And how that dry air is eroding her western side.

This image is from six hours ago, when #PAMELA was at her maximum size, roughly 500 miles wide. Before she makes landfall she is expected to strengthen again as she turns towards the North East.