ATL: DEBBY - Post-Tropical - Discussion

[FLLurker32]

NHC 5pm confirming N movement

[caneman]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

[Poonwalker]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone language and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be a flood event for many.

[caneman]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be flood event.

Agree. I think they like to smooth things out over time but she looks like she has her eyes set on Cedar Key and if so will be Tampa Bay under more wind. Already more impressive in my opinion than Idalia which was stronger when it passed by.

[robbielyn]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be flood event.

Agree. I think they like to smooth things out over time but she looks like she has her eyes set on Cedar Key.

Then why did the 5pm discussion not update it? they show it hitting upper big bend but state it’s now moving n? not arguing just asking

[eastcoastFL]

She’s really starting to wrap up now.

[caneman]

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be flood event.

Agree. I think they like to smooth things out over time but she looks like she has her eyes set on Cedar Key.

Then why did the 5pm discussion not update it? they show it hitting upper big bend but state it’s now moving n? not arguing just asking

I mentioned why perhaps in my original post. Reports are written ahead of time and they like to maintain continuity and jog or so may flatten or even out.. Its not an attack. Just an observation. It's not the immediacy of how social media is. I don't think. And margin of error more than covers it. She seems to be heading for the eastern cone.

[weeniepatrol]

From NWS Charleston..

https://forecast.weather.gov/product.ph ... hlight=off

.HYDROLOGY... Potentially historic rainfall amounts likely to bring widespread severe flash flooding to the area. A Flood Watch has been issued for all of southeast Georgia and southern South Carolina.

Debby is expected to stall near the area midweek, potentially remaining nearby into late week. Persistent deep tropical moisture advection will intersect a persistent coastal front, bringing a very prolonged period of heavy rainfall beginning Monday. Additionally, Debbie could at least briefly shift offshore Tuesday, restrengthening and bringing extremely intense rainfall with inner core convection to coastal areas. Latest guidance indicates that widespread rainfall through Thursday is likely to reach 10-20 inches, with localized amounts approaching 30 inches possible. The heaviest rainfall is likely to remain closer to the coast, with Savannah, Charleston, and Hilton Head urban areas facing an extreme flooding rainfall threat.

The record tropical cyclone rainfall for South Carolina is 23.6 inches, associated with Hurricane Florence of 2018. Debby has a significant chance to break that record. Hourly reminder : it's only August 4th

[gatorcane]

Albert-Whitted airport in St. Petersburg just reported a 56mph gust in the strong band moving through:
https://www.weather.gov/wrh/timeseries? ... ourly=true

[Poonwalker]

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be flood event.

Agree. I think they like to smooth things out over time but she looks like she has her eyes set on Cedar Key.

Then why did the 5pm discussion not update it? they show it hitting upper big bend but state it’s now moving n? not arguing just asking

I have noticed they are bound by the models and won’t depart much from them. They blend them and will give added weight to the one that has been showing the most consistency in the previous track. It’s still a blend though in the end. If anything they should consider widening the cone when real time observations show short term inconsistencies. That’s the part that catches people off guard I believe.

[Michele B]

I'm extremely interested in what the second phase of Debby's life will look like. The models have been showing several scenarios.

1 - Debby meanders over FL, GA, and the SE US, slowly spinning down to nothing and dumping a huge amount of rain. This seems like the most likely option, though there is lots of model disagreement even at this stage. Supported by the OP GFS.
2- Debby goes offshore off the SE US, strengthens some, and makes secondary landfall in GA/SC/NC, heading West. Supported by the OP Euro.
3- Debby goes offshore the SE US, strengthens, makes landfall in SC/NC, and continues heading N/NE, bringing heavy rain and wind to the mid-Atlantic and Northeast. Supported by the ICON.
4- Debby goes offshore the SE US, strengthens, makes a loop and heads SW/W back into the gulf and towards the western Gulf. Supported? by the HWRF.

I'm most interested if Debby will have a secondary peak that is stronger than it's primary peak.

The last image I saw in TWC seemed to show Debby going NE after her landfall near the Big Bend and riding Northerly up along the SE CONUS, but ONSHORE, not in the Atlantic.

Don't know why they would change that path after all these days of saying it would cross the state and head into the Atlantic and then meander around off the coast of GA.

[ronjon]

Storm surge +3.2 ft at Ft Myers. Suspect surge may approach 4-5 ft in Tampa Bay as winds turn more Southerly as Debbie moves north of their latitude. Highest wind gusts I see is 56 mph in St Pete.

[cycloneye]

This is a lot of rain that both GFS and Euro are proyecting. More than a foot.

GFS



Euro.

[FLLurker32]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be flood event.

Agree. I think they like to smooth things out over time but she looks like she has her eyes set on Cedar Key and if so will be Tampa Bay under more wind. Already more impressive in my opinion than Idalia which was stronger when it passed by.

For what it’s worth, I’m in Marion county. The difference between north big bend vs cedar key has major impacts to me. While NHC didn’t pinpoint it, my local weather service out of Jax did upgrade my Tropical Storm watch to a Tropical Storm warning with the 5pm update.

[caneman]

Storm surge +3.2 ft at Ft Myers. Suspect surge may approach 4-5 ft in Tampa Bay as winds turn more Southerly as Debbie moves north of their latitude. Highest wind gusts I see is 51 mph in St Pete.

Agree, we always get it worse from the tail living along the Gulf. Once it gets NW of us. Always!

[Michele B]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be a flood event for many.

But I don't feel they've "misrepresented" anything (not your words, but just saying) with their forecast.

THey've been showing that graphic that shows many inches of rain (up to 20" or so) in some areas. Maybe not high enough totals, though, I'll grant you that.

We are in DeSoto County and we've had several good squalls throughout the day and each one probably laid down 2-3 inches of rain. Still coming down right now, as a matter of fact.

Based on local radar I'm watching, I expect we'll see maybe one or two smaller squalls before this thing clears out of our area entirely.

[gatorcane]

Duke power outage tracker with the number of outages increasing (now 17K) as the strong bands move through Pinellas:
https://outagemaps.duke-energy.com/#/current-outages/fl

[Michele B]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be flood event.

Agree. I think they like to smooth things out over time but she looks like she has her eyes set on Cedar Key and if so will be Tampa Bay under more wind. Already more impressive in my opinion than Idalia which was stronger when it passed by.

Yes, I agree. Pretty strong for not even being a hurricane yet. We've had some significant squalls, wind gusts (if I had to guess, I'd say around 30 mph).

Debby's overall size is impressive, I can't recall how large Idalia was. I don't have stats for Idalia.

Guess I should have looked that up before typing out a reply!

[caneman]

Question and not an attack on the NHC. They're awesome. I've been tracking these things for a long time... It seems the NHC sometimes lags by a couple hours or so on what is happening. The question is this.... Does the NHC have discussion written up
ahead of time? In other words, if a NE
movement or a slower movement occured a couple hours ago, would they leave the discussion as is for continuity sake or just not having time to update? And then blend it out in the next discussion?

Look at the forecasting of Ian or better yet Charley. They often leave it as is. Partly because it’s difficult to ascertain true moment vs a wobble. That is where forecasting error percentages are reported after the fact. They did try to change the cone and keep people informed that the impacts are not represented by such. I think this one is going to surprise people because it’s truly going to be a flood event for many.

But I don't feel they've "misrepresented" anything (not your words, but just saying) with their forecast.

THey've been showing that graphic that shows many inches of rain (up to 20" or so) in some areas. Maybe not high enough totals, though, I'll grant you that.

We are in DeSoto County and we've had several good squalls throughout the day and each one probably laid down 2-3 inches of rain. Still coming down right now, as a matter of fact.

Based on local radar I'm watching, I expect we'll see maybe one or two smaller squalls before this thing clears out of our area entirely.

Nobody said anything about mis representing. It's well within the cone. PLEASE don't re-write words or twist words.

[Sciencerocks]