ATL: BERYL - Post-Tropical

[SouthDadeFish]

Looking at the basin-wide view, it's hard to even tell there is a hurricane in the Atlantic!

[SoupBone]

Looking at the basin-wide view, it's hard to even tell there is a hurricane in the Atlantic!

Not gonna lie, that's the most unimpressive (size wise) hurricane I've ever seen. It's like an afternoon thunderstorm with convection and hurricane force winds!

Disclaimer: I don't mean to minimize this system or its potential impact, but it's so damn tiny.

[GCANE]

Picking up even more steam.
Two side-by-side eyewall hot towers firing on the north eyewall.

[GCANE]

 https://twitter.com/philklotzbach/status/1015222653500583936

[Hypercane_Kyle]

12z ATCF up to 70 knots.

[NotSparta]

They're correct. The 200mb temperatures are cooler (-55C), which means a higher lapse rate and an ability to generate convection in cooler SSTs

Agreed, this is the key.
This may be an indication of overall shift in the climate for upcoming waves.
Much like the 2005 season.
2004 was strong and 2005 even stronger.
Last year we saw some helacious cat 5s.

2013 had a fairly active MDR in July and we saw naught by mid-season.

imo, 2013 is a bad comparison.

[NotSparta]

I wonder if the SST measurements are wrong? Look at Beryl go, incredible little storm.

COD floater: http://weather.cod.edu/satrad/exper/?parms=meso-meso1-02-48-0-100-1&checked=map&colorbars=

SLIDER: http://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=mesoscale_01&x=739.5&y=983&z=2&im=36&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&p%5B0%5D=1&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&s=rammb-slider

They're correct. The 200mb temperatures are cooler (-55C), which means a higher lapse rate and an ability to generate convection in cooler SSTs

Agreed, this is the key.
This may be an indication of overall shift in the climate for upcoming waves.
Much like the 2005 season.
2004 was strong and 2005 even stronger.
Last year we saw some helacious cat 5s.

2005 had a significantly more favorable base state than this yr does.

[GCANE]

They're correct. The 200mb temperatures are cooler (-55C), which means a higher lapse rate and an ability to generate convection in cooler SSTs

Agreed, this is the key.
This may be an indication of overall shift in the climate for upcoming waves.
Much like the 2005 season.
2004 was strong and 2005 even stronger.
Last year we saw some helacious cat 5s.

2013 had a fairly active MDR in July and we saw naught by mid-season.

Low 2013 ACE was by many contributed by weak Thermohaline Circulation.
Going with that argument, AMO has been increasing since 2015.
2017 was a high ACE year.
So was 2003, 2004, 2005.

[Frank2]

Beryl has about 36 hours before reaching 50 kts of widespread southwesterly shear - per the NHC it might dissipate sooner than forecast...

[txwatcher91]

Beryl has about 36 hours before reaching 50 kts of widespread southwesterly shear - per the NHC it might dissipate sooner than forecast...

If the GFS is to be believed, that area of shear and unfavorable 355k environment is forecast to weaken as Beryl approaches.

[NDG]

Beryl has about 36 hours before reaching 50 kts of widespread southwesterly shear - per the NHC it might dissipate sooner than forecast...

Is 30 knots not 50, and the TUTT is retrograding westward, but eventually Beryl will catch up to it but closer to 60 hours from now not 36, IMO.

[txwatcher91]

IMO the only thing that can slow Beryl down right now are the limited SST's (but they are increasing as he moves west) and the dry air to the north. So long as the dry air does not disrupt the circulation then a slow and steady strengthening is likely the next 36 hours.

[Florida1118]

Hurricane Beryl Discussion Number 5
NWS National Hurricane Center Miami FL AL022018
1100 AM AST Fri Jul 06 2018

Beryl is a compact hurricane that had a pinhole eye for a few
hours before more recently becoming cloud filled again. Satellite
intensity estimates from TAFB and SAB were T4.0/65 kt at 12Z, but
the Dvorak technique is constrained by width requirements of the
convective cloud tops. That may not be applicable in this case
given Beryl's extremely small size. By disregarding the width
constraints, TAFB was able to provide a data-T number of T4.5/77 kt.
As a compromise, the initial intensity is raised to 70 kt.

Beryl has not gained much latitude and is still moving quickly
westward with a 12-hour motion estimate of 275/13 kt. Mid-level
ridging over the subtropical Atlantic is expected to steer Beryl on
a westward to west-northwestward course through the forecast period.
An acceleration is forecast to begin in 36-48 hours once Beryl
becomes situated to the south of the core of the mid-level
anticyclone. Some of the track models have already shown a
northward bias since the cyclone formed yesterday, and the updated
NHC track forecast is therefore south of the typically better-
performing models. This new forecast is not too different from the
previous NHC track and is also just south of the HCCA model and the
various model consensus aids.

Despite the SHIPS model diagnostics showing increasing shear in a
few days, global model fields show a well-defined upper-level
anticyclone following the system at least for the next 3 days.
Although Beryl's expected acceleration may contribute to some
increased shear, the SHIPS model is also probably calculating
deep-layer shear over too large an area to accurately capture the
shear isolated to the cyclone's scale. Given that, the NHC
intensity forecast is at or above nearly all of the guidance
through 48 hours, which is also higher than what we've been
depicting in previous forecasts. Needless to say, it's becoming
more likely that Beryl will maintain hurricane strength when it
reaches the Lesser Antilles between 48 and 72 hours. The cyclone is
also now likely to persist beyond the 72-hour forecast point, and a
96-hour point has therefore been added to the official forecast,
showing Beryl near or over Hispaniola by day 4. By that point,
either increased shear or the terrain of Hispaniola would likely
lead to dissipation. But we shall see.

Key Messages:

1. Beryl is now expected to be a hurricane when it moves through
the Lesser Antilles Sunday night or Monday, and the chance of some
islands receiving direct impacts from wind and rainfall are
increasing. However, Beryl is a very small hurricane, and it is too
early to determine exactly where those impacts will occur.
Hurricane watches could be needed for portions of the Lesser
Antilles as soon as tonight.

2. Due to its very small size, there is greater-than-usual
uncertainty in the analysis of Beryl's current intensity, and
confidence in the official intensity forecast is also lower than
normal. Rapid changes in intensity, both up and down, that are
difficult to predict are possible during the next couple of days.

FORECAST POSITIONS AND MAX WINDS

INIT 06/1500Z 10.7N 46.5W 70 KT 80 MPH
12H 07/0000Z 11.3N 47.9W 75 KT 85 MPH
24H 07/1200Z 12.2N 50.1W 80 KT 90 MPH
36H 08/0000Z 13.3N 53.0W 85 KT 100 MPH
48H 08/1200Z 14.2N 56.6W 85 KT 100 MPH
72H 09/1200Z 16.2N 64.6W 60 KT 70 MPH
96H 10/1200Z 18.5N 72.0W 40 KT 45 MPH...INLAND OVER HISPANIOLA
120H 11/1200Z...DISSIPATED

$$
Forecaster Berg

[txwatcher91]

Latest visible images are suggesting the classic "fist" shape occurring on the right side of the circulation of Beryl. Usually this precedes a period of fast intensification, let's see if that holds true in such a small/compact storm like Beryl.

[txwatcher91]

Great writeup by NHC and this tidbit was extremely interesting:

Despite the SHIPS model diagnostics showing increasing shear in a
few days, global model fields show a well-defined upper-level
anticyclone following the system at least for the next 3 days.
Although Beryl's expected acceleration may contribute to some
increased shear, the SHIPS model is also probably calculating
deep-layer shear over too large an area to accurately capture the
shear isolated to the cyclone's scale. Given that, the NHC
intensity forecast is at or above nearly all of the guidance
through 48 hours, which is also higher than what we've been
depicting in previous forecasts. Needless to say, it's becoming
more likely that Beryl will maintain hurricane strength when it
reaches the Lesser Antilles between 48 and 72 hours. The cyclone is
also now likely to persist beyond the 72-hour forecast point, and a
96-hour point has therefore been added to the official forecast,
showing Beryl near or over Hispaniola by day 4. By that point,
either increased shear or the terrain of Hispaniola would likely
lead to dissipation. But we shall see.

[GCANE]

GFS kicking in a strong UL trof to the east as Beryl gets near PR.
Looks like a good setup for poleward outflow channel.

[shiny-pebble]

The fact that Beryl's expected peak has gone from 85MPH to 100MPH is quite impressive. I wouldn't be too surprised if Beryls able to scrape major hurricane strength, but I doubt it would happen.

Sent from my LG-H700 using Tapatalk

[GCANE]

This may actually ramp up once past the islands.
GFS is showing a possible poleward outflow channel kicking in then.

[Kazmit]

Needless to say, it's becoming
more likely that Beryl will maintain hurricane strength when it
reaches the Lesser Antilles between 48 and 72 hours. The cyclone is
also now likely to persist beyond the 72-hour forecast point, and a
96-hour point has therefore been added to the official forecast,
showing Beryl near or over Hispaniola by day 4.

Not a good trend for the Caribbean.

[Hypercane_Kyle]

A little dry air intrusion going on perhaps, the eye has become less distinct and the CDO more ragged.