Hurricane Maria

[Amped]

Worst case for San jaun is the eye skims the north coast like Irma in Cuba. Mountains will obstruct the wind a bit otherwise but it will still be pretty bad.

[wxmx]

6 minutes ago, WishingForWarmWeather said:

And this is because it takes a dip under the island puts the in in the RFQ, as well as surge issues from that direction that it came in?

That's right. Obviously it also depends on the storm intensity and size...a larger, stronger storm from the south, would trump a smaller cane from the "ideal" direction. Drz1111 made a good point about cities being established on the protected side of an island/peninsula. Also, a good deal of coastal cities prone to cyclone hits were first built a bit inland and in higher terrain. There are exceptions, of course, and most exceptions are in the CONUS

[gymengineer]

Just now, wxmx said:

The San Narciso hurricane from 1867 would be near the worst case scenario for San Juan, had it kept it's intensity as a major for a little longer.

 

Yup, local geography really matters. For example, people reflexively thought that New Orleans being on the left side of Katrina would diminish impact. But the 15-19' storm surge in the eastern part of the city is not far from the top end event (ESE to WNW path just south of the city) because that north wind across a body of water as large as Lake Pontchartrain really effectively piled up the water. 

[NJwx85]

3 minutes ago, Amped said:

Worst case for San jaun is the eye skims the north coast like Irma in Cuba. Mountains will obstruct the wind a bit otherwise but it will still be pretty bad.

The mountains are located to the South and Southeast of San Juan, and the winds should be out of East, Northeast, especially once the center moves onshore.

[donsutherland1]

Through 11 am, Hurricane Maria has continued to follow a track that is a shade north of the track taken by Hurricane #2 through the August 31-September 3 1896 period. Given the forecast synoptic pattern over the next 48-72 hours and the tracks depicted on the EPS and GEFS, such a trajectory just to the north of that taken by Hurricane #2 (1896) remains reasonable for that timeframe.  Such a track would bring Maria across Puerto Rico and north of Hispaniola.That idea is fairly close to the latest NHC forecast through 72 hours, winding up just south of the NHC's 72-hour forecast of 21.5°N 70.5° (about 21.0°N latitude at that point).

Overnight, the GEFS has moved closer to the EPS idea of Jose's retaining a larger and stronger center of circulation than had previously been the case on the GEFS. The NHC's 11 am discussion also hints at such an outcome noting:

The recent formation of convection to the southeast is beginning to give Jose the appearance of developing a large truck-tire eye with a diameter of approximately 100 nmi. Such eye patterns typically indicate a fairly stable cyclone that doesn't weaken or weakens only slowly.

The presence of Jose should reduce prospects of Maria's following the aforementioned hurricane's long-term path, which featured a bend back toward the U.S. East Coast. Therefore, considering the narrowing GEFS-EPS forecasts and a modest decrease in landfall prospects for hurricanes passing within 100 nautical miles of Maria's 11 am position over the past 24 based on historic climatology, my thinking is that the probability of U.S. landfall (CONUS) has diminished somewhat from 40% to 30%.

[clskinsfan]

I am not really concerned about surge for San Juan itself. It sits high enough that it will most likely be fine in that regard. But La Perla will definitely be an area I am sure they are evacuating for wind concerns. It is a poorer area of San Juan with not the best built homes.

[AppsRunner]

21 minutes ago, Coopdog said:

@DaDaBuh he is definitely not fraud. Just wondering how reliable.

I would never rely on that account. No actual analysis. If you call for every storm to make landfall in FL eventually you'll be right. 

[Akeem the African Dream]

On my way to Puerto Plata.  Probably going to get flooded and maybe a hurricane force gust or two.

Biggest issue for PR is going to be the complete devastation of the power grid.

[Windspeed]

Maria's core is starting to pick up a little better detail on TJUA long range. Enough detail to discern that the eyewall looks very intense and stable. Also concentric banding closer to St. Croix is pretty distant from the eyewall. Basically I don't see anything yet that would suggest Maria's eyewall can't continue deepening this afternoon.

[WishingForWarmWeather]

12 minutes ago, donsutherland1 said:

Through 11 am, Hurricane Maria has continued to follow a track that is a shade north of the track taken by Hurricane #2 through the August 31-September 3 1896 period. Given the forecast synoptic pattern over the next 48-72 hours and the tracks depicted on the EPS and GEFS, such a trajectory just to the north of that taken by Hurricane #2 (1896) remains reasonable for that timeframe.  Such a track would bring Maria across Puerto Rico and north of Hispaniola.That idea is fairly close to the latest NHC forecast through 72 hours, winding up just south of the NHC's 72-hour forecast of 21.5°N 70.5° (about 21.0°N latitude at that point).

Overnight, the GEFS has moved closer to the EPS idea of Jose's retaining a larger and stronger center of circulation than had previously been the case on the GEFS. The NHC's 11 am discussion also hints at such an outcome noting:

The recent formation of convection to the southeast is beginning to give Jose the appearance of developing a large truck-tire eye with a diameter of approximately 100 nmi. Such eye patterns typically indicate a fairly stable cyclone that doesn't weaken or weakens only slowly.

The presence of Jose should reduce prospects of Maria's following the aforementioned hurricane's long-term path, which featured a bend back toward the U.S. East Coast. Therefore, considering the narrowing GEFS-EPS forecasts and a modest decrease in landfall prospects for hurricanes passing within 100 nautical miles of Maria's 11 am position over the past 24 based on historic climatology, my thinking is that the probability of U.S. landfall (CONUS) has diminished somewhat from 40% to 30%.

Don, I really love these. This sort of discussion should become standard, I wish NHC would fully adopt this. I know they've tried here and there to start implementing it but nowhere near to the degree of depth and knowledge and data that you bring. I learn so much from you every day. Thank you. 

 

 

[jojo762]

Looks like recon just left Curacao.

[Derecho!]

1 hour ago, Coopdog said:

@DaDaBuh he is definitely not fraud. Just wondering how reliable.

That account is a worthless, embarrassing, fraudulent joke. It frankly terrifies me that anyone would think that had any relevance to tropical forecasting.

Trust me on this, I have two decades of experience debunking fraudulent tropical forecasters. 

[adiabatic13]

A little contraction of the eyewall beginning, along with cooling cloud tops...looks like we have an intensifying system again this afternoon. Hoping for a dual wind max in the upcoming reconn package.

edit: once again a very unusual ERC-less Atl storm, though what would have transpired last night had Dominica not been in her way can be speculated upon 

[Eskimo Joe]

I'm surprised there isn't a second radar on Puerto Rico (NW side?), given the terrain.  

[Drz1111]

2 hours ago, wxmx said:

And Kingston

Kingston actually reasonably protected from hits from the west by the blue mountains, which tends both to weaken approaching storms and deflect them (remember Ivan), and though elevations lower, has plenty of land to the east for late-season west carib cyclones.  It's vulnerable to a hit straight from the south, but that's an unusual track likely requiring a very late season storm.  One day it'll take one, but the odds are pretty low in any given year.

San Juan is well-protected compared to say, Ponce, from the typical W-WNW CV track; it's most vulnerable to a storm deflecting WSW b/c of a super strong WAR.  Again, possible, but relatively uncommon. Also helps that the water WNW from San Juan generally has a bit less TCHP than the water in the Caribbean or north of Hispanola.

[Windspeed]

Recon should be in Maria's core in about 30 minutes. We'll see if she has deepened further. I suspect she has. Perhaps around 920 mb.

[JC-CT]

1 minute ago, Windspeed said:

Recon should be in Maria's core in about 30 minutes. We'll see if she has deepened further. I suspect she has. Perhaps around 920 mb.

 

Certainly looks that way on infrared.

[Jim Martin]

[Windspeed]

Certainly looks that way on infrared.

Sure does...

[eyewall]

It is still possible the eye could miss just NE of PR which would be the best case but we shall see.

[wxeyeNH]

With the eye looking so good on infrared Im surprised the vis. shows a low cloud cover.  We will know very shortly what's going on, recon getting close...

[Windspeed]

The concentric banding really needs to get its act together and tighten in a lot closer to the eyewall before it will begin to abate low level convergence. That's really the only thing in structure that might weaken Maria before landfall. Man this looks intense...

[wxmx]

28 minutes ago, Drz1111 said:

Kingston actually reasonably protected from hits from the west by the blue mountains, which tends both to weaken approaching storms and deflect them (remember Ivan), and though elevations lower, has plenty of land to the east for late-season west carib cyclones.  It's vulnerable to a hit straight from the south, but that's an unusual track likely requiring a very late season storm.  One day it'll take one, but the odds are pretty low in any given year.

San Juan is well-protected compared to say, Ponce, from the typical W-WNW CV track; it's most vulnerable to a storm deflecting WSW b/c of a super strong WAR.  Again, possible, but relatively uncommon. Also helps that the water WNW from San Juan generally has a bit less TCHP than the water in the Caribbean or north of Hispanola.

I don't know, it seems pretty vulnerable...prone to surge, a very fragile airport location (in a barrier island)...and Blue Mountains did nothing during Gilbert...it even wobbled in the worst way possible towards Kingston. A place like Montego Bay looks much more protected. There have been plenty cyclones moving around Kingston in late season, coming from the SW, it's just that they have been relatively weak.

[JC-CT]

 

[CoastalWx]

12 minutes ago, eyewall said:

It is still possible the eye could miss just NE of PR which would be the best case but we shall see.

Except for the USVI.

[jpeters3]

8 minutes ago, wxeyeNH said:

With the eye looking so good on infrared Im surprised the vis. shows a low cloud cover.  We will know very shortly what's going on, recon getting close...

 

Some degree of low-cloud cover is common, even among the most intense hurricanes.  This probably because subsidence cannot penetrate into the boundary layer, so you get a thermal structure with a warm moist boundary layer, and a warm cap a few km up.  Below that cap, shallow convection is possible. 

[eyewall]

Just now, CoastalWx said:

Except for the USVI.

Yes that is true. 

[Windspeed]

16 minutes ago, wxeyeNH said:

With the eye looking so good on infrared Im surprised the vis. shows a low cloud cover.  We will know very shortly what's going on, recon getting close...
 

Low clouds are nearly always present at the 800 mb layer in an intense eye on visible satellite imagery. People make it seem like it's clear blue skies looking up from the surface, but it usually looks more like a haze with breaks and low thin stratus cloud clusters spinning around. You can see stars, sun and moon through them from the surface though.

[SnowLover22]

Looks like recon found 155 knot surface winds and pressure down to 919mb.

[wxeyeNH]

Recon   919.6mb?