ATL: DELTA - Post-Tropical - Discussion

[Stormgodess]

Per law enforcement radio traffic, lots of downed trees around here, including at least one on a house, as well as a number of vehicles in ditches. The wildest call was an officer or deputy radio'ing with a nervous voice that there was a transformer on fire next to a house . . . his own!

Livingston or Tangipahoa parish? Calls for first responders here was a tree fell on a man and he was trapped. A tree fell on a house but the female occupant was not harmed. And a roof came off of a house

What do you think the windspeed actually been for us here around Albany. Because seriously we have been getting pounded for hours now! And it also looks like Delta took a jog to the east once inland?

[CrazyC83]

Per law enforcement radio traffic, lots of downed trees around here, including at least one on a house, as well as a number of vehicles in ditches. The wildest call was an officer or deputy radio'ing with a nervous voice that there was a transformer on fire next to a house . . . his own!

Livingston or Tangipahoa parish? Calls for first responders here was a tree fell on a man and he was trapped. A tree fell on a house but the female occupant was not harmed. And a roof came off of a house

What do you think the windspeed actually been for us here around Albany. Because seriously we have been getting pounded for hours now! And it also looks like Delta took a jog to the east once inland?

No more than low-end tropical storm force. That's enough to knock down trees and power lines though.

[Steve]

No word on Sabine Pass. Hope that power comes back soon. As far as Albany, if you go to the NWS site and click current conditions, both Baton Rouge and Hammond show 30’s and gusts into the 30’s and 40’s (Hammond upper 40’s last report). Not a total win here. Though I did see 2 flashes (assuming transformers), my garbage can blew over in a gust and another one blew a plastic table into my drink and spilled it. Haha. Hoping for a few more hours of the 20/30’s and a little more half sideways rainfall.

[LARanger]

This has made me decide to invest in at least a cheap anemometer, since my scale for this has been very scientific:
"breeze", "wind", "gust", and the occasional "glad I'm not drinking" gust.

My indoor barometer is reading 1000 hPa, down 15 from earlier today.

[Stormgodess]

No word on Sabine Pass. Hope that power comes back soon. As far as Albany, if you go to the NWS site and click current conditions, both Baton Rouge and Hammond show 30’s and gusts into the 30’s and 40’s (Hammond upper 40’s last report). Not a total win here. Though I did see 2 flashes (assuming transformers), my garbage can blew over in a gust and another one blew a plastic table into my drink and spilled it. Haha. Hoping for a few more hours of the 20/30’s and a little more half sideways rainfall.

The only way I know how to describe it, is its felt like we have had long extended gusts, with lulls in between, instead of the other way around?

[Stormgodess]

This has made me decide to invest in at least a cheap anemometer, since my scale for this has been very scientific:
"breeze", "wind", "gust", and the occasional "glad I'm not drinking" gust.

My indoor barometer is reading 1000 hPa, down 15 from earlier today.

Yeh seems worth the investment. This is a solid frame house on a concrete slab and it sounds, and feels, like its getting hit by a herd of 1000 Bulls!

[SconnieCane]

Apologies if this has been posted already. Live Storms Media video showing trailer overturned and blown into road in Pecan Island.



Link: https://youtu.be/S7_BfeyKamo

[AnnularCane]

My aunt in Ponchatoula just emailed me. She says she's been having 50 mph gusts with 25-35 mph sustained winds. She still has power so far though, and she's kind of surprised about that.

[Steve]

No word on Sabine Pass. Hope that power comes back soon. As far as Albany, if you go to the NWS site and click current conditions, both Baton Rouge and Hammond show 30’s and gusts into the 30’s and 40’s (Hammond upper 40’s last report). Not a total win here. Though I did see 2 flashes (assuming transformers), my garbage can blew over in a gust and another one blew a plastic table into my drink and spilled it. Haha. Hoping for a few more hours of the 20/30’s and a little more half sideways rainfall.

The only way I know how to describe it, is its felt like we have had long extended gusts, with lulls in between, instead of the other way around?

Word. Sounds like real deal sustained close to and sometimes TS winds. Down here in New Orleans, I’m getting an occasional mid and upper 30’s gust. Lotta rustling and an occasional bit of rain. We have a couple more thin bands so maybe a couple hours of more fun here

[Stormgodess]

Well lost power guys... Last bit of battery. Everyone stay safe! Thanks for all the info.

[AnnularCane]

How often does a hurricane make landfall in the US without a tornado watch being issued?

[CrazyC83]

How often does a hurricane make landfall in the US without a tornado watch being issued?

Not too often, but instability over land is quite low - probably because of the time of day it hit. However, there is a tornado threat on Saturday in AL/MS.

[LARanger]

I was on my laptop working outside and heard odd noises, then more. Eventually I went to investigate and had to help remove an errant 12 foot trampoline with side nets from the neighbor's roof before the next big gust tossed it onto my car or house (or person, for that matter). It is now tied down safely-ish.

It's amazing how the gusts are so much worse now than before. Not sure if that is because the dry air isn't hauling the water load or if it's the current angle that involves less land interaction (a more direct path from the gulf). I presume the latter, but either way I'm not a fan.

[us89]

How often does a hurricane make landfall in the US without a tornado watch being issued?

Not too often, but instability over land is quite low - probably because of the time of day it hit. However, there is a tornado threat on Saturday in AL/MS.

Latest SPC outlook moved the highest tornado threat tomorrow over to the east AL/west GA region, which means I’m now in my first slight risk in quite some time. Although we’ll be east of the better shear, instability will be a bit easier to come by than over towards MS.

Some of the hi-res models like the HRRR seem to be hinting at a setup where the feeder bands coalesce into a squall line of sorts, with the potential for quite a bit of clearing in front of it. If something like that pans out, tomorrow evening might bring some of the most interesting weather we’ve seen in a good while here.

[CrazyC83]

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.

AL262020, DELTA, 33,
20201004, 0000, , LO, 15.4N, 73.5W, 25, 1006,
20201004, 0600, , LO, 15.8N, 74.4W, 25, 1006,
20201004, 1200, , LO, 16.1N, 75.3W, 30, 1005,
20201004, 1800, , LO, 16.4N, 76.2W, 30, 1005,
20201005, 0000, , TD, 16.5N, 77.0W, 30, 1005,
20201005, 0600, , TS, 16.4N, 77.7W, 35, 1002,
20201005, 1200, , TS, 16.3N, 78.3W, 45, 996,
20201005, 1800, , TS, 16.3N, 79.1W, 60, 984,
20201006, 0000, , HU, 16.5N, 79.8W, 70, 978,
20201006, 0600, , HU, 17.2N, 80.7W, 85, 971,
20201006, 1200, , HU, 17.8N, 82.0W, 105, 958,
20201006, 1800, , HU, 18.5N, 83.4W, 120, 954,
20201007, 0000, , HU, 19.2N, 84.5W, 100, 962,
20201007, 0600, , HU, 20.1N, 85.7W, 95, 969,
20201007, 1015, L, HU, 20.8N, 87.1W, 90, 972,
20201007, 1200, , HU, 21.1N, 87.4W, 80, 974,
20201007, 1800, , HU, 21.7N, 88.8W, 75, 978,
20201008, 0000, , HU, 22.3N, 90.2W, 80, 972,
20201008, 0600, , HU, 23.0N, 91.4W, 85, 971,
20201008, 1200, , HU, 23.7N, 92.4W, 90, 968,
20201008, 1800, , HU, 24.4N, 93.1W, 100, 963,
20201009, 0000, , HU, 25.3N, 93.5W, 105, 955,
20201009, 0300, P, HU, 25.8N, 93.6W, 105, 952,
20201009, 0600, , HU, 26.3N, 93.7W, 105, 954,
20201009, 1200, , HU, 27.5N, 93.8W, 100, 958,
20201009, 1800, , HU, 28.7N, 93.6W, 90, 964,
20201009, 2300, L, HU, 29.8N, 93.1W, 80, 968,
20201010, 0000, , HU, 30.0N, 93.0W, 75, 970,
20201010, 0600, , TS, 31.4N, 92.3W, 50, 984,
20201010, 1200, , TS, 32.8N, 90.9W, 40, 991,
20201010, 1800, , TD, 33.5N, 89.8W, 30, 997,

Some key thoughts:

* The genesis and early life are unchanged.
* The rapid intensification, followed by weakening on October 6-7 is sharpened based on Recon data. It is assumed that Delta peaked when the 121 kt SFMR and 130 kt FL winds were recorded. That results in a peak intensity of 120 kt, a slight decrease from operational.
* The landfall intensity in the Yucatan is 90 kt. That is based on the aircraft data which I thought was quite generous.
* The intensities in the Gulf are largely unchanged as well. The secondary peak remains 105 kt, although the pressure is adjusted to 952 mb at 0300Z October 9 (non-synoptic time) based on buoy observations. 110 kt was considered based on the highest FL winds of 125 kt, but I did respect the SFMR (peaking at 100 kt).
* The landfall intensity in Louisiana I estimate was 80 kt. The highest FL winds near landfall were 104 kt, but at that point 90% was likely inappropriate due to cooler water and a stable boundary layer. The highest SFMR near landfall was 77 kt (with caveats), while no station recorded sustained hurricane winds (a few came close). The highest radar returns I saw were 96 kt at 8,000 feet, which translates to about 82 kt at the surface. The landfall pressure I estimate was 968 mb, based on a blend of two dropsondes in the last 45 minutes before landfall (967 and 970) and a surface report of 972 mb just outside the eye center.

[TheStormExpert]

 https://twitter.com/stuostro/status/1314758299032735749

[cycloneye]

 https://twitter.com/NWSWPC/status/1314887914288013313

[Frank P]

MS coast last night experienced A decent feeder band from Delta around 2 am this morning and brought with it a 5 foot storm surge and recorded wind gusts at the GPT harbor of 49.5 mph and in BSL 47 mph. So our 25% chance of forecast TS winds were more like 100% chance... Prayers to all of LA who experienced much worse conditions...

[Steve]

Looks like the Panhandle will deal with the feeder line today as it slowly moves east feeding north. It comes with marine warnings so probably some 30-40 gusts with it. All in all, Delta could have been a lot worse, but I'm sure some of extreme SWLA got bad. Lots of effects over several hundred miles (east to west) of Gulf Coast.

https://radar.weather.gov/ridge/Conus/s ... y_loop.php

I also look at Delta as kind of the anti-Juan ('85) and anti-Opal. Both of those drug down cold fronts and the Fall with them. Opal was strong enough to bring down a big cold front, and Juan stuck around long enough to connect to a front that brought down the Fall. This actually brings up warm sector air until the next front/trough swings by. October weather can go lots of ways and obviously so can October Gulf storms.

[TallyTracker]

Looks like the Panhandle will deal with the feeder line today as it slowly moves east feeding north. It comes with marine warnings so probably some 30-40 gusts with it. All in all, Delta could have been a lot worse, but I'm sure some of extreme SWLA got bad. Lots of effects over several hundred miles (east to west) of Gulf Coast.

https://radar.weather.gov/ridge/Conus/s ... y_loop.php

I also look at Delta as kind of the anti-Juan ('85) and anti-Opal. Both of those drug down cold fronts and the Fall with them. Opal was strong enough to bring down a big cold front, and Juan stuck around long enough to connect to a front that brought down the Fall. This actually brings up warm sector air until the next front/trough swings by. October weather can go lots of ways and obviously so can October Gulf storms.

Yeah it’s been breezy, overcast, and warm and muggy this morning here in the Panhandle. Expecting some solid rain later today. It’s already hitting the Pensacola area now.