hawkeye_wx

I'm surprised they don't have another recon plane in there now. NHC's schedule says there will be a new plane in the storm every three hours, beginning at 2030z this afternoon.

The pressure dropped 1 mb since the last recon pass (50 minutes). The visible loop shows new towers beginning to pinwheel around the eye, so it should be entering another strengthening phase. It's just a question of how fast it can solidify the eyewall and drop the pressure.

The third recon pass this morning is also 978 mb, so Idalia remains in a holding pattern. Landfall is only 24 hours away, so it will really need to step on the gas later today.

Hurricane Franklin, well off the US southeast coast, has cratered to 926 mb this evening. 72 hours ago it was 1003 mb and highly sheared.

Dropsonde says 926 mb.... very impressive. The cloud tops have warmed a bit, so perhaps Franklin has peaked.

This run of the GFS has the storm at 989 mb Tuesday evening. It's probably 985 mb now, so unlikely to be right.

Franklin has become a very impressive hurricane. Let's hope it can hold this intensity until the next recon plane gets in there this evening.

Models mostly predicted this system would have issues until it got into the gulf Monday night and Tuesday. It has done well to get down to 990 mb, but, as others have noted, it has yet to be able to wrap the convection around the surface center. It continues to try, but so far it's just a series of strong cells trying hard to hold onto the center while being pushed back south/southeast by some dry, shearing flow.

We spend a lot of time watching the models to see how strong these storms may get. We are doing that now with Idalia. Last night's 00z Euro is already off by 30 mb for Franklin. The Euro predicted a 966 mb hurricane this morning.

The pressure fell 6-7 mb during the 1.5 hour period between the first and second recon pass.

Franklin is really taking off now. The new recon plane found 941 mb (extrap) and 123 kt flight level wind. Update: 943 mb per recon dropsonde. The NHC may quickly upgrade this to 135 mph.

965 mb now per the new recon.

That's a pretty good surface pressure for a young, disjointed system with a naked center.

There are clearly some negative forces affecting TD10. Convection blew up this morning and tried to align the various levels together, but satellite and Cancun radar suggest an area of sinking air is pressing down from the north, which is eroding the convection and pushing it south of the weak surface circulation. All of the deep moisture is south and well east of the center. The global models must have seen this. Edit: The surface center has performed a bit of a loop overnight and this morning. It passed southward over Cozumel, then continued southward for a while, but then turned east, passing under this morning's convection, and has now moved well out from under the convection and may be moving northeastward.

TD10's overall appearance was better 24 hours ago. It is trying to get its act together southeast of Cozumel this morning. The question is can it maintain the convection today and organize the core or will it fizzle during d-min like yesterday? The first recon plane is headed in from the east, but it is still several hours away.

The new recon dropsonde says 970 mb.

Yep. Warm and bone dry for the foreseeable future. The early August rain was just a brief tease.

Some of the models were right about the vorticity dropping southward and not doing too much, for now. Cancun radar shows a bit of a misalignment. The convection and mid level rotation appears a bit east of the surface center. The surface center moved ssw for a while, but now appears to be getting pulled back east a bit toward the new convection.

This system really lost its core convection this afternoon.

Oddly, the GFS drops the 500 mb vorticity southward, but keeps the weak surface low stationary, off the northeast tip of the Yucatan.

All the hurricane models (hwrf, hmon, hafs) have greatly ramped up the strength as it shoots northward toward landfall.

Does anyone have any thoughts about why models continue to refuse to strengthen this system at all through Monday, even though they all now show it remaining over the Caribbean and under upper ridging?

This looks like a tropical depression. The convection was increasing overnight, but this morning it has clearly developed into a spiraling pattern, with a center just east of the northeast tip of the Yucatan. The visible loop also clearly shows a north/northwest flow over the northeast Yucatan.

The latest center dropsonde recorded 986 mb.

The shear has become more favorable, but the core will have to mix the dry air out and build better convection over the next day or two.