Login to AccuWeather.com Premium Login to AccuWeather.com Professional Login to AccuWeather.com RadarPlus AccuWeather.com

Welcome Guest ( Log In | Register )

691 Pages V   1 2 3 > » 

Phased Vort
Posted on: Yesterday, 11:23 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(stretchct @ Aug 18 2017, 09:52 PM) *
Not really sure whats holding it back. Outflow remains challanged, especially the NE section. Surface, 850 and 700 vorts stack nice, 500mb is a little off. Too young for a 200mb vort.
Shear


Shear tendency


Mid shear


Another look at the wind profile per gfs - not much shear 850-500mb


Its outrunning the dry air behind it, with somewhat good air in front.


Guess I'll find out tomorrow.


Good post!
  Forum: Current Tropical Season Weather · Post Preview: #2234731 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 11:23 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


00Z GFS threatens south Texas with Harvey as a tropical storm.
  Forum: Current Tropical Season Weather · Post Preview: #2234730 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 01:05 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


They also found a lower pressure.

Attached Image
  Forum: Current Tropical Season Weather · Post Preview: #2234675 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 01:02 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(stretchct @ Aug 18 2017, 12:43 PM) *
Vort message with 56kt surface winds. Thought that would be thrown out based on flight level winds.
Guess not.

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 18th day of the month at 15:45Z
Agency: United States Air Force
Aircraft: Lockheed WC-130J Hercules with reg. number AF96-5302
Storm Number & Year: 09 in 2017
Storm Name: Harvey (flight in the North Atlantic basin)
Mission Number: 2
Observation Number: 17
A. Time of Center Fix: 18th day of the month at 13:58:40Z
B. Center Fix Coordinates: 13°00'N 61°25'W (13.N 61.4167W)
B. Center Fix Location: 17 statute miles (27 km) to the SW (229°) from Kingstown, Saint Vincent and the Grenadines.
C. Minimum Height at Standard Level: 1,491m (4,892ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 56kts (~ 64.4mph)
E. Location of the Estimated Maximum Surface Wind Inbound: 10 nautical miles (12 statute miles) to the W (270°) of center fix
F. Maximum Flight Level Wind Inbound: From 285° at 23kts (From the WNW at ~ 26.5mph)
G. Location of Maximum Flight Level Wind Inbound: 10 nautical miles (12 statute miles) to the N (360°) of center fix
H. Minimum Sea Level Pressure: 1008mb (29.77 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 16°C (61°F) at a pressure alt. of 1,521m (4,990ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 21°C (70°F) at a pressure alt. of 1,518m (4,980ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 16°C (61°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Wind and Pressure
N. Fix Level: 850mb
O. Navigational Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 2 nautical miles

Remarks Section:
Maximum Flight Level Wind: 47kts (~ 54.1mph) which was observed 63 nautical miles (72 statute miles) to the NNW (343°) from the flight level center at 13:03:30Z
Maximum Flight Level Wind Outbound: 32kts (~ 36.8mph) which was observed 75 nautical miles (86 statute miles) to the ENE (66°) from the flight level center at 14:23:30Z
Sea Level Pressure Extrapolation From: 850mb



Good post. Thanks.
  Forum: Current Tropical Season Weather · Post Preview: #2234674 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 12:11 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(Undertakerson @ Aug 18 2017, 10:35 AM) *
Great disco Carlos. Very important overview of the elements and aspects at play.



Thanks.

I wanted to see why the ECMWF was bring Harvey further NW, and avoiding Nicaragua.



By the way, the 12Z GFS now also avoids colliding Harvey´s energy with Nicaragua.
  Forum: Current Tropical Season Weather · Post Preview: #2234666 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 12:09 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(Undertakerson @ Aug 18 2017, 10:36 AM) *
Levi put out an excellent disco

https://www.youtube.com/watch?v=rHLwWPlQAu0



Yep.

That backing upper level low is the entity I refered to as cut off trough of low pressure energy.
  Forum: Current Tropical Season Weather · Post Preview: #2234665 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 10:53 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


Updated NHC track, as of 11AM AST, has adjusted to the NW, especially over the Yucatan and GOMEX.

Attached Image


QUOTE
000
WTNT44 KNHC 181450
TCDAT4

Tropical Storm Harvey Discussion Number 5
NWS National Hurricane Center Miami FL AL092017
1100 AM AST Fri Aug 18 2017

The structure of Harvey has changed little during the past several
hours, and overall the storm is poorly organized. The low-level
center is near the eastern edge of the convective mass due
to the affects of 15 kt of vertical wind shear. In addition,
surface observations and Air Force Reserve Hurricane Hunter data
suggest that the 850-mb center is located west or southwest of the
surface center. Based on the aircraft and surface data, the central
pressure is near 1005 mb and the initial intensity remains 35 kt.

The initial motion is a quick 270/18. A strong low- to mid-level
ridge north of the cyclone should keep Harvey on this general motion
for the next 3-4 days, with the system moving from the eastern to
the western Caribbean Sea during this time. Late in the forecast
period, a more northerly motion is expected when Harvey passes near
or over portions of Central America, the Yucatan Peninsula, and
eastern Mexico. The new forecast track remains in the center of the
guidance, and only minor changes were made to the previous track.

The current shear should persist for the next 48 h or so, and thus
the intensity forecast continues the trend of slow strengthening
during this time. After that, conditions appear favorable for
strengthening, with the main uncertainty being how much land Harvey
will encounter. The ECMWF keeps the cyclone a little north of
Nicaragua and Honduras and allows more room for development, while
the GFS forecasts landfall in northeastern Nicaragua and thus has a
weaker intensity. The new NHC forecast is close to the previous
one in showing a peak intensity below hurricane strength, but
the confidence in this portion of the forecast is low.

FORECAST POSITIONS AND MAX WINDS

INIT 18/1500Z 13.1N 61.3W 35 KT 40 MPH
12H 19/0000Z 13.3N 63.8W 35 KT 40 MPH
24H 19/1200Z 13.6N 67.3W 40 KT 45 MPH
36H 20/0000Z 14.0N 71.1W 40 KT 45 MPH
48H 20/1200Z 14.3N 75.0W 50 KT 60 MPH
72H 21/1200Z 15.0N 82.0W 60 KT 70 MPH
96H 22/1200Z 16.5N 87.5W 55 KT 65 MPH
120H 23/1200Z 18.5N 91.0W 30 KT 35 MPH...INLAND

$$
Forecaster Beven


  Forum: Current Tropical Season Weather · Post Preview: #2234657 · Replies: · Views: 6,196

Phased Vort
Posted on: Yesterday, 10:03 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


12Z ECMWF yesterday had Harvey going into the southern GOMEX, as it felt a slight influence coming from a trough passing over the western Great Lakes.

On today´s 00Z ECMWF there a dominant ridge over the eastern to central US, as Harvey approaches Belize, but then, that ridge gets kicked out by the same incoming trough shown on yesterday´s 12Z run, albeit more pronounced on this run and also working with a broken off loose piece of trough energy over the central GOMEX coast.

The incoming trough and that piece of cut off trough energy together, is enough to attract or pull Harvey northwestward towards the central GOMEX coast, as these 3 entities interact. Eventually, the trough passes and leaves an area of weak steering currents over the south central US and over the GOMEX northern coast, and with a new ridge building in from the upper Midwest. During this period, Harvey looks to become nearly stationary, and then eventually starts to move towards the west aiming for Texas, as it starts to interact with the new building ridge.

Attached Image


Attached Image


Attached Image


Attached Image



Attached Image


Tropical Tidbits
  Forum: Current Tropical Season Weather · Post Preview: #2234653 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 17 2017, 09:45 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(PoconoSnow @ Aug 17 2017, 08:31 PM) *
18z navy brings Harvey into the gomex




12Z ECMWF did that as well. Although it was to the southern GOMEX.

  Forum: Current Tropical Season Weather · Post Preview: #2234628 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 17 2017, 03:57 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(stretchct @ Aug 17 2017, 03:50 PM) *
Tropical Storm Harvey Advisory Number 2
NWS National Hurricane Center Miami FL AL092017
500 PM AST Thu Aug 17 2017

...HURRICANE HUNTER FINDS THAT THE DISTURBANCE HAS BECOME
TROPICAL STORM HARVEY...
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...13.0N 55.8W
ABOUT 250 MI...400 KM E OF BARBADOS
ABOUT 355 MI...570 KM E OF ST. LUCIA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 18 MPH...30 KM/H
MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES



As expected.

Welcome Harvey.
  Forum: Current Tropical Season Weather · Post Preview: #2234590 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 17 2017, 03:42 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


The issue is that the ECMWF does not develop 91L as of yet. But it does take the wave all the way to south Florida.

Without ECMWF support for a developed tropical cyclone, the chances are smaller.

Let´s see what future runs will show.
  Forum: Current Tropical Season Weather · Post Preview: #2234585 · Replies: · Views: 2,380

Phased Vort
Posted on: Aug 17 2017, 03:28 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


So far the lowest pressure found comes from OBS 30:

Attached Image

  Forum: Current Tropical Season Weather · Post Preview: #2234584 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 17 2017, 03:19 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


Yea.

It seems PTC9, as per RECON, already has tropical force winds.

They may be looking for the west wind to confirm a closed circulation.


  Forum: Current Tropical Season Weather · Post Preview: #2234583 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 14 2017, 10:26 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


Folks, these posts are funny alright, but let´s try to not let them get too frequent as they are off-topic, please.
  Forum: Current Tropical Season Weather · Post Preview: #2234375 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 14 2017, 10:12 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(Undertakerson @ Aug 14 2017, 05:39 AM) *
Almost as if the GFS is trying to see the Euro solution of a dual core (two systems essentially), quashing the energy it had used, combined, to make the EC threat - now seems to fracture that energy field and allow the southern piece (Caribbean cruising piece) to go it alone. More or less, allowing neither to develop.

Oy vey!


Nice one.

But still, if that energy that goes towards the Caribbean and develops as it heads towards the GOMEX, i must say that it´s a pretty nasty outcome to have for the GOMEX coast.

Could get ugly.
  Forum: Current Tropical Season Weather · Post Preview: #2234373 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 14 2017, 05:17 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


Very interesting two weeks ahead of us.

The GFS now takes the punch out of 91L, which may be the first step to move towards a more ECMWF-ish solution.

It seems the ECMWF develops the system that goes into the GOMEX from another wave, but it may be the fusion of the 91L wave with trough of low pressure. With 24 hour frames it gets hard to know.
  Forum: Current Tropical Season Weather · Post Preview: #2234360 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 13 2017, 03:15 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


The 12Z ECMWF develops tow tropical systems.

91L is the system behind and tracks to the north.

This run, develops the wave ahead of 91L and takes it into the Caribbean and ends with it south of Miami on frame 240.

At least that what it seems to be on the 12Z ECMWF.
  Forum: Current Tropical Season Weather · Post Preview: #2234332 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 13 2017, 03:05 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(shane o mac @ Aug 13 2017, 03:03 PM) *
Only issue its 9-10 days out we saw how that turned out the past few threats .. but hope things start to heat up however ..



Yea.

I threat does not necessarily mean that it will actually come to fruition.

  Forum: Current Tropical Season Weather · Post Preview: #2234330 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 13 2017, 03:04 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


On the RGB satellite animation, it does indeed look good enough to be Gert.

  Forum: Current Tropical Season Weather · Post Preview: #2234329 · Replies: · Views: 10,895

Phased Vort
Posted on: Aug 13 2017, 12:29 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


12Z GFS, continues to follow its previous runs.

Threat still alive.
  Forum: Current Tropical Season Weather · Post Preview: #2234324 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 13 2017, 10:09 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


QUOTE(Undertakerson @ Aug 13 2017, 04:53 AM) *
So then, when the next run of the might Euro, after the threatening looking CMC, look like this - then what?

[attachment=327363:ecmwf_z5...p_atl_11.png]



It seems the tropics will pick up big time.

But it makes sence. We are getting close to September, which screams, the pick of tropical cyclone season/ the most active part of the season historically.
  Forum: Current Tropical Season Weather · Post Preview: #2234322 · Replies: · Views: 13,148

Phased Vort
Posted on: Aug 13 2017, 10:07 AM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


Here we go!

Wave just off the cost of Africa.

Both the GFS and ECMWF have them. Of course, differing intensity, but similar track towards the Bahamas, and then they have a difference in opinions.
  Forum: Current Tropical Season Weather · Post Preview: #2234321 · Replies: · Views: 6,196

Phased Vort
Posted on: Aug 12 2017, 09:56 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


TD8 forms after all from invest 99L.

QUOTE
000
WTNT43 KNHC 130248
TCDAT3

Tropical Depression Eight Discussion Number 1
NWS National Hurricane Center Miami FL AL082017
1100 PM EDT Sat Aug 12 2017

Late afternoon GOES-16 visible satellite images showed that the
circulation associated with the low pressure located northeast of
the Bahamas had become better defined. Since that time, the
night-time microphysics RGB product and other infrared satellite
pictures have continued to show an improvement in the circulation,
and recent ASCAT data show that the system has acquired a well-
defined center. Deep convection is organized in a large curved band,
however the center is located near the western edge of the band.
NOAA buoy 41046 located southeast of the center reported 25 to 30 kt
winds earlier this evening, and the scatterometer data support an
initial wind speed of 30 kt.

The depression is moving north-northwestward or 330/11 kt.
The depression should move north-northwestward to northward
around the western side of a deep-layer ridge over the central
Atlantic through Sunday night. It is expected to reach the
mid-latitude westerlies by late Monday and begin to accelerate
northeastward ahead of a short-wave trough that will be approaching
the northeastern United States. The steering currents are well
established over the western Atlantic and the track guidance is in
good agreement on the forecast scenario. The NHC track forecast lies
near the various consensus aids.

The intensity forecast is more problematic. The system is expected
to traverse warm water and remain in a low-shear environment during
the next day or so, but intrusions of dry mid-level air are likely
to limit strengthening. The statistical guidance and the HWRF favor
more significant intensification than the global models, which
generally do not show much deepening. In deference to the global
models, the NHC forecast is below the consensus, especially later in
the period. The system is likely to become extratropical in 3 to 4
days, and the extratropical portion of the forecast is based on
guidance provided by the NOAA Ocean Prediction Center.


FORECAST POSITIONS AND MAX WINDS

INIT 13/0300Z 25.3N 70.3W 30 KT 35 MPH
12H 13/1200Z 27.0N 71.2W 35 KT 40 MPH
24H 14/0000Z 29.0N 71.9W 40 KT 45 MPH
36H 14/1200Z 30.7N 72.0W 45 KT 50 MPH
48H 15/0000Z 32.2N 71.4W 50 KT 60 MPH
72H 16/0000Z 36.2N 66.9W 55 KT 65 MPH
96H 17/0000Z 41.5N 54.5W 50 KT 60 MPH...POST-TROP/EXTRATROP
120H 18/0000Z 45.5N 39.0W 45 KT 50 MPH...POST-TROP/EXTRATROP

$$
Forecaster Brown


TD#8 NHC Forecast Discussion?
  Forum: Current Tropical Season Weather · Post Preview: #2234294 · Replies: · Views: 10,895

Phased Vort
Posted on: Aug 12 2017, 06:00 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


ECMWF at the 00Z run and 12Z run today, do show the energy for this possible cyclone taking more or less the same path as shown by the GFS, albeit, a much weaker version of a system.
  Forum: Current Tropical Season Weather · Post Preview: #2234279 · Replies: · Views: 13,148

Phased Vort
Posted on: Aug 8 2017, 01:55 PM


Rank: F5 Superstorm
***

Group: SuperModerator
Posts: 18,528
Joined: 13-January 08
From: White Plains, NY
Member No.: 12,468


Today´s 12Z ECMWF run continues to indicate development in about 3 days from now.

  Forum: Current Tropical Season Weather · Post Preview: #2234053 · Replies: · Views: 10,895

691 Pages V   1 2 3 > » 

New Posts  New Replies
No New Posts  No New Replies
Hot topic  Hot Topic (New)
No new  Hot Topic (No New)
Poll  Poll (New)
No new votes  Poll (No New)
Closed  Locked Topic
Moved  Moved Topic
 

RSS Lo-Fi Version Time is now: 19th August 2017 - 01:39 PM