ATL: NICHOLAS - Post-Tropical - Discussion

[NDG]

Recon heading back, it flew well south of the LLC seen on Satellite.

[HurricaneBrain]

I think we have a new center that is much further north. Cone might shift west in alignment with model guidance but latest models have the center initialized much further south than the new CoC I’m seeing on satellite.

[Sciencerocks]

[NDG]

I think we have a new center that is much further north. Cone might shift west in alignment with model guidance but latest models have the center initialized much further south than the new CoC I’m seeing on satellite.

We can at least throw out the 12z HWRF which had the LLC near 22.5 & 95W for right about now.

[dpep4]

What are the chances of warnings being moved farther north with this system. From what I have seen the storm is going to make land fall north of the warned areas ( knowing that this will be a coast hugger I understand the need for the warned areas). Also what are the chances of this becoming a low end hurricane?

The general consensus seems to be most likely a strong TS but it could realistically become a cat 1 hurricane.

I'd say a hurricane is a good possibility to even likely, with Cat 2 within a realistic range, based not so much on science but decades of observing the often too conservative early (to not so early) forecasts of the NWS and NHC that frequently end up being revised upward.

Look at the Sea Surface Temps available, fast ramp ups in the gulf this time of year are common. Obviously there are very good potential reasons that it might not do that (possible dry air, shear, land interaction, inhibited organization, etc.) But time and again the NWS and NHC have often been slow to discuss high end possibilities until later than private mets, only to later upgrade. Not nearly all the time, but too often. Mentioning the high end possibility is not the same as forecasting it, but would give a helpful range to prepare for before its too late to do much prep.

For example, after I've already read a local Houston TV met mention that discussions with the NWS of issuing a hurricane watch this afternoon have taken place, I see this:

Area Forecast Discussion
National Weather Service Houston/Galveston TX
140 PM CDT Sun Sep 12 2021

Winds:
- Too early to say. For planning purposes, those along the coast
might want to begin preparing for tropical storm storm force
winds as we head closer toward Tuesday until things hopefully
become more clear cut and the forecast refined.

Most laymen would read that as "OK, so trop storm is probably the worst we'll see." Most expect the forecast to be for the most likely scenario, but also mention to prepare for a higher realistic worst case option. Thus it seems irresponsible to not mention a hurricane potential if it is realistically possible. Most people have a 'Prepare for the worst, hope for the best' expectation of their forecasters.

If Nick ends up hitting as a hurricane in the Houston NWS zone, whoever wrote that should be at least temporarily reassigned and policy adjusted. To be clear, the NWS and NHC are full of very talented people who absolutely know what they are doing. I get the sense this is mostly a policies problem more than anything else.

I'm preparing for a Cat 2/3 and expecting TS to Cat 1, based on all the forecasts I've read so far.

[wxman57]

Broad, elongated circulation. Still trying to get organized. I like 12Z Euro that takes it into NE Mexico then stalls east of San Antonio. Has 61+ inches of rain near La Grange. Last run had 25-30" just SW of Houston. GFS rain looks more reasonable. Still thinking moderate TS with only a small area of strong winds NE-E of the center making landfall near or just west of Matagorda Bay early Tuesday. Winds in Houston likely 20-30 mph with higher gusts in thunderstorms Tuesday.

[IcyTundra]

Broad, elongated circulation. Still trying to get organized. I like 12Z Euro that takes it into NE Mexico then stalls east of San Antonio. Has 61+ inches of rain near La Grange. Last run had 25-30" just SW of Houston. GFS rain looks more reasonable.

I agree GFS seems more realistic.

[psyclone]

Nicholas is generating wicked convection. I like to think of tropical storms and low end canes as water storms. Most of the danger is water...either falling from the sky or the sea in motion. This storm may continue a theme this year of freshwater flooding

[grapealcoholic]

Best convection we've seen out a storm this season

[Sciencerocks]

Best convection we've seen out a storm this season

Better then Ida's?

[Clearcloudz]

Salute to all the PRO METS who have to convey this storm to the general public as this is not as easy and draws a lot of criticism. This storm is going to catch general public by surprise and once this storm unfolds criticism will be through the roof as its the weekend and not many are paying attention.

[IcyTundra]

Salute to all the PRO METS who have to convey this storm to the general public as this is not as easy and draws a lot of criticism. This storm is going to catch general public by surprise and once this storm unfolds criticism will be through the roof as its the weekend and not many are paying attention.

Yep people are surely going to blame the mets for not informing them but in reality they are just not staying aware.

[xironman]

I think we have a new center that is much further north. Cone might shift west in alignment with model guidance but latest models have the center initialized much further south than the new CoC I’m seeing on satellite.

The eddy is there. The gyre may swing it around a bit before it consolidates and is truly the center.

[grapealcoholic]

Best convection we've seen out a storm this season

Better then Ida's?

It's deeper than Ida's. Not too surprising either since upper-level temps are cooler and SSTs are actually a little bit warmer

edit: actually forgot about Grace in the BOC

[aperson]

There's more to convection than cloud top temps.

[grapealcoholic]

There's more to convection than cloud top temps.

Obviously organization matters but just brute forcing latent heat fluxes is another way to do it. See Gamma 2020

[HurricaneBrain]

That eddy is becoming the new CoC. Watching the next few hours.

[aspen]

Well that’s gonna draw the LLC further NE. This is the best convection I’ve seen for a new TS in the basin this year.

[grapealcoholic]

I'd expect a quick center reformation under that deep convection

[Clearcloudz]

 https://twitter.com/pppapin/status/1437149852647964674