cheezyWXguy wrote:USTropics wrote:12z HAFS-A coming in (I'm a HAFS-A hugger for Melissa), it actually increases pressure some until about 8PM ET tonight (relative to what the run started at):
https://i.imgur.com/2MItvl1.png
A new RI period begins shortly after that, with a drop to 931mb in 12 hours (8AM ET):
https://i.imgur.com/zDtdlx6.png
Now that’s been a few hours since you made this post, and now that Melissa has resumed intensification, do you have any ideas as to what particular reason for the hafs’ leveling off and resuming of intensification? Do you think it was able to accurately see the dry air intrusion we observed, and do you think it could be due to the storm’s western inflow channel being blocked from moist inflow by Jamaica to the north? Is the resuming of intensification due to that channel no longer being blocked now that the storm has moved sufficiently westward?
Hope that wasn’t too many questions
The short answer is, good luck figuring out the physics of a category 4 hurricane
I'll give my opinion on some of your questions:From 15z (11AM ET) to 18z (2PM ET) it did have a drop in pressure, but then an increase thereafter. A good comparison case is the HAFS-B, which had a smooth decrease in pressure throughout the day (which verified). The main difference here is in initialization, where HAFS-A did not have quite the compact core that HAFS-B did:
If we look at projected IR-simulations for both models 3 hours later, that gives the most clues about the outflow restriction (and core representation) and some of that inflow restriction like you were stating (overdone by the HAFS-A at this timestep):
From actual satellite imagery, we can see which one verified better:
With that said, it was a very brief oscillation on the HAFS-A, and by 8PM tonight it was showing a rapid intensification period again.
