Major Hurricane Delta

[hlcater]

1 minute ago, tiger_deF said:

Unflagged 119kt in NE quadrant

those are flight level winds.

[Windspeed]

Yeah FL supports upgrade as well. The pressure drop supports upgrade. That is inevitably going to mix down. I'd say based on the pressure drop alone that recon will make several more passes. We have significant intensification in progress.

 

 

 

 

[WEATHER53]

What is the track once inland 

[mattb65]

1 minute ago, tiger_deF said:

Unflagged 119kt in NE quadrant

That's the flight level, the surface some were still around 90 kt. Need dropsonde to get a better idea on the winds.

Nevertheless recon verified what is obvious on visible and IR that the storm is clearly strengthening.

[Alfoman]

8 minutes ago, tiger_deF said:

Unflagged 119kt in NE quadrant

Winds lagging at the surface still (90-95kt) but this is not far away from becoming a strong cat 3. Warrants an upgrade to 115 mph for sure. Recon going to be around over the next 2-3 hours as structural improvements continue and Delta continues to at least try and get some convection upshear...going to be interesting to say the least 

Edit: this is the sonde in the SW eyewall...

[Moderately Unstable]

2 minutes ago, tiger_deF said:

Unflagged 119kt in NE quadrant

 

1 minute ago, hlcater said:

those are flight level winds.

Both of you are correct! More to the point, the FL winds just measured are around 15 knots higher than the most recent aircraft fix prior to this one. The SE Eyewall sonde that just came in has a pressure of 966, and was not at the center of the storm. I agree, evidence suggests that, as was forecast, the storm has re-intensified to a low cat 3. The next forecasting elements are going to be determining the timing of the turn, speed as it approaches landfall (since that will affect the impacts along the coast). In the process of typing, the eye sonde came in at 959. 

 

MU

[hlcater]

Just now, Moderately Unstable said:

 

Both of you are correct! More to the point, the FL winds just measured are around 15 knots higher than the most recent aircraft fix prior to this one. The SE Eyewall sonde that just came in has a pressure of 966, and was not at the center of the storm. I agree, evidence suggests that, as was forecast, the storm has re-intensified to a low cat 3. The next forecasting elements are going to be determining the timing of the turn, speed as it approaches landfall (since that will affect the impacts along the coast). In the process of typing, the eye sonde came in at 959. 

 

MU

the 119kt measurement was at flight level. SFMRs are being funny at the surface, with a 39kt reading right where you'd expect vmax to be. Not entirely sure they're reliable, but who knows. Standard reduction and pressure falls lend themselves to an upgrade to 100kt C3.

[JasonOH]

SFMR gets messed up in high rain rates. Those low values were all right in the middle of a huge rain rate spike. Dropsonde should give us a better idea of what’s going on since SFMR couldn’t that pass.

[the ghost of leroy]

Walks, talks, and quacks like a 100kt storm

[MSUgulfcoaster]

2 minutes ago, Moderately Unstable said:

 

Both of you are correct! More to the point, the FL winds just measured are around 15 knots higher than the most recent aircraft fix prior to this one. The SE Eyewall sonde that just came in has a pressure of 966, and was not at the center of the storm. I agree, evidence suggests that, as was forecast, the storm has re-intensified to a low cat 3. The next forecasting elements are going to be determining the timing of the turn, speed as it approaches landfall (since that will affect the impacts along the coast). In the process of typing, the eye sonde came in at 959. 

 

MU

A lot of others said basically the same as this above, and it’s spot on. This is a cat 3 storm right now, it’s intensifying rapidly, and the strong winds will mix down. Things are going to get really interesting over the next 6 hours as Delta pushes its upper limits of intensification. Good thing we will have recon flying through there for the entirety. 
 

when the pressure plummets, and FL winds drastically increase, it’s never a good thing, especially when it is out in the middle of the GoM. Prayers go out to LA, been a tough year for the Northern Gulf. 

[olafminesaw]

1 minute ago, JasonOH said:

SFMR gets messed up in high rain rates. Those low values were all right in the middle of a huge rain rate spike. Dropsonde should give us a better idea of what’s going on since SFMR couldn’t that pass.

Dropsnode 88kts it's at the surface, but 121kts just above the surface

[Alfoman]

BULLETIN
Hurricane Delta Advisory Number  17
NWS National Hurricane Center Miami FL       AL262020
400 PM CDT Thu Oct 08 2020

...DELTA REGAINS MAJOR HURRICANE STRENGTH OVER THE WESTERN GULF OF
MEXICO...
...HURRICANE CONDITIONS AND LIFE-THREATENING STORM SURGE EXPECTED
TO BEGIN ALONG PORTIONS OF THE NORTHERN GULF COAST ON FRIDAY...


SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...24.8N 93.4W
ABOUT 345 MI...555 KM S OF CAMERON LOUISIANA
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES

[MSUgulfcoaster]

Oh wow, 121 kt just above the surface in the NE eye wall. That’s muchhhhhh higher than expected and not a good sign. 
 

New update- cat 3 with 115mph winds, 959 mb

[Maestrobjwa]

7 minutes ago, the ghost of leroy said:

Walks, talks, and quacks like a 100kt storm

So now the question is...what happens when a hurricane quacks?

[Windspeed]

Eyewall is closed. With that dropsonde showing 121 kts just above surface level, I'd say strengthening will continue as recon makes more passes. Think this will make a run at Cat 4 during DMAX.

[MUWX]

1 minute ago, Windspeed said:

Eyewall is closed. With that dropsonde showing 121 kts just above surface level, I'd say strengthening will continue as recon makes more passes. Think this will make a run at Cat 4 during DMAX.

Eye is a decent amount smaller than it was earlier today. 

[STxVortex]

10 minutes ago, MUWX said:

Eye is a decent amount smaller than it was earlier today. 

YBMTI.  I saw that, and was going to comment that it had contracted ~20% [35-28] from recent reports.  

[the ghost of leroy]

51 minutes ago, WEATHER53 said:

What is the track once inland 

Right over your house. Expect epic flooding

[Windspeed]

Dakota Smith at CIRA (Atmospheric Research Division at CSU) has the best satellite posts.

[Windspeed]

-93°C in those towers within the NW semicircle.

[Radtechwxman]

Still seems like eastern side of storm hasn't taken off as much as western side. Cloud tops much colder in western semicircle. I see NHC is forecasting it just shy of cat 4 before the weakening starts. Have it landfalling as a major cane now. 

[Floydbuster]

 

[JasonOH]

949.2 extrap. 95kt FL and 95kt SFMR on the inbound.
 

Edit: Large area of 100kt FL on the outbound.

[Moderately Unstable]

It appears based on the latest flight data, that the 12z HMON did a touch better than the 12z HWRF on pressure and wind speed estimates. In looking at the synoptic dynamics, both models suggest an ingest of dry air into the core in the 3 hours to landfall time period, with a commensurate rise in pressure and drop of wind speeds. If you buy the HMON guidance, or more generally its trends, you'd still have a cat 3 storm at landfall, barely, but with poor mixing down to the surface and an open eye to the south.  That said, most guidance does probably correctly maintain a core of hurricane force winds aloft at the 850-925mb layer at an expanding radius as the storm travels inland, which could mix down in stonger precip bands and lead to hurricane force gusts in south central LA at the north end of the H warning area. The storm has turned as expected and now appears to be heading nearly due North. As it has done this, the eye has become less apparent on IR--though it did this a couple times earlier today so it is too early to say it won't improve again within the next hour. As an aside, the western part of the eye is visible on reflectivity from the KBRO radar and has been for a couple of hours now. Too far atm to say anything conclusive about what I've seen but figured I'd mention it since you can certainly see the banding at least. 

 

MU

[Radtechwxman]

Looking at water vapor seems like some drier air has impacted the NE quadrant. This could be a reason the convection isn't as robust. Seems like our eye has become obscured again. Not sure we're going to hit 125 like NHC is forecasting. Curious to see what Delta does as we approach the convective max time. 

[HillsdaleMIWeather]

Newest pass shows it's still strengthening 

[Windspeed]

Excellent post by Philippe Papin:

 https://twitter.com/pppapin/status/1314350609924067328?s=19

 

 

[Windspeed]

Hmm.. Wouldn't have thought W GOM majors were so rare in October.

[Amped]

16 minutes ago, Windspeed said:

Excellent post by Philippe Papin:

https://twitter.com/pppapin/status/1314350609924067328?s=19

 

 

That is not a very hot look at landfall.  Irene 2.0

[Windspeed]

Yeah again intensification this evening and whatever more Delta can muster by midday tomorrow matters only in fetch for surge. Winds are going to come down by landfall but the radius of 34+ wind is going to continue increasing. This is going to be a surge event.