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Sorry, here was the D3 text and categorical risk. Doesn't say tor risk but I think we know... ...Delmarva into the Carolinas... Considerable strengthening of the deep-layer wind field is forecast on Sunday in advance of the midlevel trough. However, considerable cloud cover and areas of precipitation appear likely to limit air mass destabilization within the poleward-expanding warm sector. Nonetheless, boundary-layer dewpoints in the upper 60s to mid 70s will support pockets of modest instability, especially in areas where cloud breaks may occur. And given the presence of relatively strong low-level and deep-layer shear, a conditional risk for severe storms capable of damaging winds and perhaps a few tornadoes will exist Sunday into Sunday evening. Higher severe weather probabilities may be required in later forecasts if subsequent model data indicate greater instability than that currently depicted.

Isaias is now a major hurricane. 7:20 AM CDT Fri Oct 09 Location: 27.0°N 87.6°W Moving: NNE at 15 mph Min pressure: 959 mb Max sustained: 120 mph

Latest pressure went up so slightly from 958 to 959. Maybe a sign that it has maxed out and some weakening could start happening during the day.

Another convective tower trying to wrap around the eye as it fights some intense shear on the West side. Wish we had one more pass to see if pressure drops or holds steady

Isaias is now a Major Hurricane with sustained winds of 120 in and near the eyewall. Tropical Storm Force wind extend out just about 200 miles from the center.

Peak Season Forecast (Aug 20-Oct 20) Named Storms: 5 (6) Hurricanes: 3 (1) Major Hurricanes: 1 (1) Dolly, Edouard, Fay, Gonzalo, Hanna, Isaias (MH) Homebrew delivers again...

https://pbs.twimg.com/media/HUMGXpaXQAAwuKb?format=jpg&name=medium

Isaias now a major hurricane.

Yeah, very tough call. Just a few hours made the difference here, though it's incredibly impressive how well GDM has been through the entirety of this one. Like you said in another post, it was easy to hedge east for this one, and GDM never backed down on a higher end peak. Well, keep in mind that Idalia hit one of the least populated areas of the state. Idalia's eyewall was legit, but less damage=less need for retirement. That won't be the case with this one, even if it's weakening at the end, because it's hitting real population centers. Not to mention the yet to be seen inland impacts in the south. Agree with this too. There's going to be a line of discussion here tonight about why we're not seeing G125 across the landfall zone and it'll be because 1) that's not how things work lol and 2) the strongest winds in a decaying core may be concentrated in a few spots. Still bad to be clear with other impacts and with wind itself, but as I've found, eyewall dynamics and impacts are more mesoscale than people tend to realize.

If there is a time for further strengthening it’s now through 18z or so. Definitely good venting helping out.

And it’s officially a Cat 3

Bad attitude. Reservoirs fill just as well on Tuesday/Wednesday rain as they do on Saturday/Sunday rain. eta: Reservoirs fill best on HECS/MECS snow melt. They just do.

Good catskills skiing??

Fully supported by recon data. That’s why NHC waited at 8 am knowing they had a plane heading straight for the money pass. Great job hurricane hunters. This might peak at cat 4

7:20 AM CDT Fri Oct 09 Location: 27.0°N 87.6°W Moving: NNE at 15 mph Min pressure: 959 mb Max sustained: 120 mph

If it weakens right before landfall and the core erodes like some models have, best winds may be found in the convection modeled on the NW side of the center. Would make it more difficult to maximize best winds in that area accounting for forward motion. You really need good mixing to maximize your best winds at the surface. That’s why it makes all the difference when a storm is intensifying as it makes landfall vs weakening. I’m not minimizing this, just stating what we know with these storms.

Likely near peak intensity at just over major hurricanes strength right now with pressure leveling off around 960 MB and winds catching up to pressure now supporting a major hurricane around 115-120 at the surface

Upgrade coming. What a pass. Might be 120

If Idalia didn't get retired, this one probably won't be either. Idalia got up to high end C4 speed, and this one is barely going to be a C3.

@WxWatcher007It was such a tough call on whether to pull the trigger on major peak or not when I issued the first stab on Wednesday...I'm happy with the forecast overall, but looks like I may have underestimated my 110mph peak a bit. I thought conditions would be hostile by dawn today, so that is the difference. Also happy with the Thursday night hedge for best deepening window.

Latest recon finds 117-120kt FL winds. 959.3mb pressure extrapolated. 960mb dropsonde in the center with a 6kt wind.

A nice way to display the impacts (I think a little over cooked on the inland gusts though)

Isaias is on the cusp of becoming a major hurricane this morning, and as you all know by now it is explicitly forecast to become a major shortly. Although not a pristine satellite appearance, Isaias from both satellite and recon is clearly an intensifying hurricane at this hour with an eye, deep convection continuing to wrap upshear in bursts, and rapidly falling pressure in between center fixes as a result. While the season has been defined by futility overall, with both Fay and Edouard we had systems that were able to maximize their limited geographic environment to pop, and Isaias is the best example of a system taking advantage of the narrowest of windows for development and intensification this season. If Isaias were moving in any other heading, it would be getting annihilated right now. Isaias is the beneficiary of excellent divergence and a relative heading that precludes shear so far from disrupting the increasingly strong inner core. This has also allowed the hurricane to avoid disruption from dry air entrainment. A few days ago, that was a key question for me as the core was establishing itself. Normally a northern Gulf landfall, especially this time of year, features last minute continental air disrupting things, and while that may eventually erode part of the system, that's not happening right now. The resilience of Isaias will be tested in the coming hours, and if you're still reading here's the real thrust of the post: the NHC is right to be concerned about a delay in weakening. I do still think that shear will eventually disrupt Isaias, but it may not happen until landfall is occurring. Operationally, that may mean it's difficult for the NHC to confirm weakening as the center is moving onshore. More importantly, in an expanding wind field, it could be the case that we see the intensification plateau later followed by pressure rises and then winds weakening. For folks along the coast, any lag between the impact of shear and weakening may lead to a C3 landfall. This is a razor's edge forecast. It seems clear that unlike many of the recent Gulf examples there will not be intensification up to landfall, but weakening may be blunted or delayed. The latest HAFS A & B both show more intensification before some weakening--right at landfall. Both essentially have a major landfall in the next 12 hours. Perhaps more significantly, the GDM, which I've been raving about for two years now and with good reason--it's by far the best hurricane ensemble--shows very little change in intensity until landfall is effectively occurring. Pay less attention to intensity and more to whether there's weakening evident and when. At this point, I think folks in the landfall zone should be prepared for a C3 impact. It likely won't be at its peak, which is important from an impacts standpoint (the storms intensifying at landfall tend to "feel" worse than ones weakening at the same intensity), but between surge, rainfall, and a likely significant severe weather threat, this is likely to be a highly impactful hurricane. I'm not there for this one, but stay safe to everyone down there.

It's a tough call because like they said in the statement, a 6-hour delay in the onset of shear could mean 20mph in LF intensity....so they are making the right call hedging more intense. They have to balance the need to disseminate as precise a forecast as possible to the public with the need to convey a sense of urgency commensurate with the worst possible outcome that can be reasonably expected.

Looks like recon quit transmitting data?