Windspeed

The issue here is a western MDR TUTT. The GFS seems to drive a TC through it, north of the Greater Antilles; but obviously that scenario isn't ideal for westward moving TC into WNW steering flow. I wouldn't get too excited yet. The pattern is crap for any long range CV system. We're just going to have to see what early September brings. I am not confident for above normal activity. I already stated this. We'll see... Yes, of course a home-grown frontal remnant system could develop or a CAG system in the western Caribbean. But that is very low probability. It's just going to take some serious patience to see how this all irons out. To put it mildly, I think the whole setup is garbage. Regardless of the AMO state, I do not like the upper level environment and state of subsidence right now.

Hurricane Dora is only a few hours from crossing the dateline and becoming a typhoon. Shear is noticably increasing as well.

Dora looks healthy again after a bout with shear. Only a temporary reprieve as southwesterly shear is forecast to pick up again on Friday, or Saturday, rather, as it will have crossed the dateline and became a typhoon.

Very strong trades have been wreaking havoc on Hawaii the past few days. Influenced by tight gradient funneling between the strong ridge to the north and Major Hurricane Dora to the south. The Lee side of the volcanic topography and the gradient is fueling ongoing devastating wildfires.

Dora is very intense with a presentation looking like a high end Cat 4 right now.

000 NOUS44 KMRX 081529 PNSMRX TNZ067-068-082200- Public Information Statement National Weather Service Morristown TN 1129 AM EDT Tue Aug 8 2023 ...Preliminary EF-2 Storm Damage of the Lovell Crossing Apartments, Knoxville Tennessee... The preliminary damage assessments of the Lovell Crossing Apartments in Knoxville Tennessee is a EF2 tornado with winds up to 130 mph and a path width of 200 yards. The National Weather Service office in Morristown TN will continue to assess the damage across the area today. The survey is in relation to the severe thunderstorms that moved through the area on Monday, August 7, 2023. A final assessment including results of the survey are expected to be completed and transmitted via a Public Information Statement by 5 PM Today. The storm survey information will also be available on our website at https://www.weather.gov/mrx $$

Dora has generated up to 31 points of ACE already.

Yikes! Yes, I've been spreading the word to everyone. Regardless of the slight tornado risk, it looks like a legitimate threat of wind damage as these storms move through.

Look at the setup for mid-month/Aug. 15th-16th on both recent runs of the ECMWF and the GFS. That look is not a favorable one for anything approaching the Caribbean. There are poorly positioned TUTTs and strong upper-level westerlies across Caribbean. It looks to me that something would need to get lucky positioning-wise north of the Greater Antilles. But any disturbance is going to have to overcome shear and subsidence in the MDR first. Generally, upper levels are calming down in around this time regardless of lingering subsidence in the central basin. You'll see signs in modeling from 500 to 200 hpa. I don't see those signs yet.

I don't see any window of above normal activity now. We're getting into the midrange and I just don't see it. Looks like +ENSO is going to beat down +AMO to me. Any hyperactive stretch is going to be a surprise for me. Perhaps there is a pocket of favoribility in late August before El Niño takes over.

Potential severe in the eastern Valley tomorrow. Slight tornado potential prior to MCS formation. https://www.spc.noaa.gov/products/outlook/day2otlk.html Excerpt:

SSTs are marginal 26.5-27°C for what you would expect to support a Category 4. But given the donut annular structure and relative fast motion of 18kts, the eyewall appears to have just enough OHC to maintain intensity. Will be interesting to see how long Dora can keep this up. The TC has generated 20 ACE points so far. SSTs remain around 27°C on a due west heading. However, there does appear to be some increasing easterly trades in a few days south of Hawaii which may impart some mid-level shear, or possibly force surrounding dry air into the circulation.

I'm wondering if that's going to be a theme of the season. Yes, it's just the beginning of August, but there are bad placements of southern heat ridges and TUTTs to contend with that may very well not go away due to ENSO and strong upper evacuation out of the EPAC, regardless of the +AMO. Beating a dead horse here, but perhaps it bears repeating. That August window of activity I was counting on looks to be getting smaller and smaller. Of course, even if a window of favorable upper pattern evolves over the MDR within the next few weeks as hinted by modeling, we've still got that pesky dry air and subsidence to deal with, which isn't abnormal in early-to-mid August.

This evening through Tuesday will have better conditions and a moister environment to support development. 95L really fell apart yesterday, though, and with only weak vorticity right now, I'm not sure it will be able to take advantage. Might be dead to rights unless it can reignite some persistent convection along its axis that has separated from the ITCZ. The caveat here is that even if 95L were to grt its act together and develop into a TC during the next few days, it looks like it will ultimately be doomed to hostile conditions in the central Caribbean.

No surprise to see Don looking heathier as the core is now riding over an area of ≥26°C SSTs.

Not too shabby....

Regardless of eventual outcome, there is enough organization here that this likely does close off at the surface and get classification. It is maintaining persistent convection, though displaced west of the nascent LLC. Short-term confidence is high. Long-term confidence is low.

There is a very favorable 400-200mb setup north of the Antilles that will evolve if it tracks there despite any SAL. It's the only real intense pattern I can imagine 95L having. Otherwise, it's stiff displacement at 400mb across the central Caribbean, which I just do not see it surviving.

It's doing enough to be interesting, so here we go. I honestly don't feel too confident in its future synoptic setup. It needs to gain latitude. There are multiple scenarios north of the Greater Antilles that make this a significant cyclone, but a more southerly track looks like a sheared mess. Too much trade vs. westerlies predominant within the deep Caribbean. If this system is able to close off and stack sooner than later, then perhaps we have a serious TC. Otherwise, it likely gets shredded.

Cold upper tropospheric temps over Don allowing it to overachieve in sub 26° SSTs. Cooler SSTs due to its own upwelling and development out of a surface trough and sub-tropical cold pool airmass. Still, just enough thermal driven instability now at the surface layer to sustain its core. Don't know if it will reach hurricane intensity, but it does have an eyewall right now.

The Caribbean looks too sheared if the MDR disturbance is driven that far west. It needs to develop and gain some latitude prior to the islands otherwise. A track through or just north of the northern Leewards gives it a better shot. I'm just not expecting much here. Probably another week or two until conditions can temporarily improve for something more serious.

Got a lemon. The disturbance isn't expected to develop until within the central MDR or on approach to the islands if it can hold together.

What will be the state of those vortices though? Will they have upper level support to become hurricanes, or will they be sheared weak systems? It's quite possible we get a number of TCs form in the MDR due to the OHC thermal support, but the WATL and Caribbean may still have unfavorable mid-to-upper level Westerlies. Of course, it only takes one to get into the right synoptic setup that just happens to be favorable for an intense landfall somewhere. Can the record +AMO overcome a strong +ENSO? This is going to be what everyone is focused on for meat of ASO. Big uncertainties on how this plays out with little to no analogs to compare.

Here's a little blurp about the current -PDO state. Obviously the +AMO is still cranking. It really is a blessing that we're staring down the barrel of a a moderate to strong +ENSO. If it were neutral, the 2023 ASO would have been a huge ACE producing behemoth. We may very well still see a few intense hurricanes, as reiterated previously, if something can sneak west into a temporarily favorable upper pattern and low-level easterly steering.