Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Tropical Storm Bret


Recommended Posts

  • Replies 277
  • Created
  • Last Reply

000

URNT12 KNHC 180700

VORTEX DATA MESSAGE AL982011

A. 18/06:37:30Z

B. 27 deg 07 min N

077 deg 48 min W

C. 850 mb 1448 m

D. 45 kt

E. 334 deg 7 nm

F. 101 deg 46 kt

G. 003 deg 11 nm

H. 1001 mb

I. 15 C / 1466 m

J. 22 C / 1462 m

K. NA / NA

L. NA

M. NA

N. 12345 / 8

O. 0.02 / 5 nm

P. AF308 0202A BRET OB 08

MAX FL WIND 52 KT SE QUAD 05:16:00Z

Curvature North and East. Heavy rain inbound from NE.

Link to comment
Share on other sites

The latest microwave shows a system that's still not vertically stacked. I'm thinking dry/stable air (well defined on microwave to the north) is going to be a major factor in preventing this storm from becoming a hurricane, although it should still be able to slowly intensify in the next 24 hours before the shear gets to it.

dbsju1.jpg

Link to comment
Share on other sites

Still lacking a bit on the deep convection... but visible looks halfway decent, although it still doesn't appear vertically stacked. I'm still liking a 50 knot peak intensity atm over the next 24 hours, although if it can get vertically stacked before then, it could get a little stronger than that.

v7qxpd.jpg

Link to comment
Share on other sites

When trying to forecast where this low was going to exist 3-7 days out, all the global guidance (including all the global ensemble members) had this low in a band between 29-32N latitude. The ECMWF ensemble members were most emphatic on its development, as shortwave energy across Georgia and the Carolinas was stronger on the EC solution. This is also why the medium range forecast (when a low was depicted anyway) shifted from a westward drift into the Georgia coast to offshore the Southeast by Wednesday night. The first model, Tuesday night, which showed this system could be a bit farther south was the 00z NAM, which continued to advertise a position somewhat north of the Northwest Bahamas (and south of all other guidance) through Wednesday night, in forecasts valid Saturday morning-Sunday morning. There was no ensemble support for this solution, so it was not considered viable. Oops. Sometimes the outlier still verifies...which shows that ensemble forecasting still has a way to go to capture all possible outcomes.

It has gone further south than they ever expected... very interesting. I'm not implying anything yet but it's supposed to be turning the complete opposite way very soon.

and that radar shot is also interesting,

Link to comment
Share on other sites

Another bout of intensification in the works? An interesting eye like feature is showing up, while some healthy convection on the west side of the circulation has sprouted.

It will depend how vertically stacked recon finds Bret this afternoon. Looks rather impressive on visible, but convection is still a little on the weak side. Maybe a 50 knot system?

nqd36b.jpg

Edit: Forgot to look at radar, and I have to say, it looks like its undergone a significant evolution in the last few hours towards a more organized system.

23sya9f.gif

Link to comment
Share on other sites

Looking at the 12z model guidance as well... I might have to make a significant change in my forecast in the middle and long ranges. If Bret survives the 36-72 hour period, it looks like an upper low might cutoff to the west of the system sheltering it from the strong westerly flow beyond 72 hours. I don't know how much will be left of the system by that point, but it bears watching, since the first trough located east of the system is too weak and too far east to pick up the storm completely, and it will take a second stronger upper level trough to finish the job beyond 120 hours.

Link to comment
Share on other sites

I guess it can't hurt to post the VDM, I doubt everyone has access to it at work and whatnot...

Dropsonde measured 55 kts. SE of the center at the surface.

Product: Air Force Vortex Message (URNT12 KNHC)

Transmitted: 18th day of the month at 19:58Z

Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 307)

Storm Number & Year: 02L in 2011

Storm Name: Bret (flight in the North Atlantic basin)

Mission Number: 3

Observation Number: 04

A. Time of Center Fix: 18th day of the month at 19:29:50Z

B. Center Fix Coordinates: 28°09'N 77°04'W (28.15N 77.0667W)

B. Center Fix Location: 209 miles (337 km) to the ENE (62°) from West Palm Beach, FL, USA.

C. Minimum Height at Standard Level: 1,406m (4,613ft) at 850mb

D. Estimated (by SFMR or visually) Maximum Surface Wind: 60kts (~ 69.0mph)

E. Location of the Estimated Maximum Surface Wind: 11 nautical miles (13 statute miles) to the W (271°) of center fix

F. Maximum Flight Level Wind Inbound: From 5° at 53kts (From the N at ~ 61.0mph)

G. Location of Maximum Flight Level Wind Inbound: 10 nautical miles (12 statute miles) to the W (269°) of center fix

H. Minimum Sea Level Pressure: 998mb (29.47 inHg) - Extrapolated

I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 15°C (59°F) at a pressure alt. of 1,536m (5,039ft)

J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 21°C (70°F) at a pressure alt. of 1,522m (4,993ft)

K. Dewpoint Temp (collected at same location as temp inside eye): 15°C (59°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, Radar, Wind, Pressure and Temperature

N. Fix Level: 850mb

O. Navigation Fix Accuracy: 0.02 nautical miles

O. Meteorological Accuracy: 0 nautical miles

Remarks Section - Remarks That Were Decoded...

Maximum Flight Level Wind: 53kts (~ 61.0mph) in the west quadrant at 19:26:30Z

Sea Level Pressure Extrapolation From: 850mb

Maximum Flight Level Temp: 21°C (70°F) which was observed 7 nautical miles to the NW (311°) from the flight level center

Remarks Section - Additional Remarks...

PRELIMINARY, DO NOT RETRANSMIT

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...