Thread: Sub-Tropical Storm Laura

188
ABNT20 KNHC 281200
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SUN SEP 28 2008

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON HURRICANE
KYLE...LOCATED ABOUT 165 MILES SOUTH-SOUTHEAST OF NANTUCKET
MASSACHUSETTS.

A BROAD AREA OF LOW PRESSURE CENTERED OVER THE YUCATAN PENINSULA
CONTINUES TO PRODUCE A LARGE DISORGANIZED AREA OF CLOUDINESS AND
SHOWERS. ANY DEVELOPMENT OF THIS SYSTEM IS LIKELY TO BE SLOW TO
OCCUR UNTIL THE LOW DRIFTS SLOWLY NORTHWARD AWAY FROM YUCATAN.
HEAVY RAINS AND LOCALIZED FLOODING ARE POSSIBLE OVER PORTIONS OF
SOUTHERN MEXICO...THE YUCATAN PENINSULA ...BELIZE AND GUATEMALA.

THUNDERSTORM ACTIVITY HAS BECOME A LITTLE BETTER ORGANIZED IN
ASSOCIATION WITH A LARGE NON-TROPICAL LOW PRESSURE AREA LOCATED
OVER THE CENTRAL NORTH ATLANTIC OCEAN ABOUT 650 MILES
WEST-SOUTHWEST OF THE WESTERNMOST AZORES ISLANDS. THIS SYSTEM HAS
THE POTENTIAL TO BECOME A SUBTROPICAL OR TROPICAL CYCLONE OVER THE
NEXT COUPLE OF DAYS AS IT MOVES GENERALLY WESTWARD AT 10 TO 15 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$

FORECASTER BLAKE

abnt20 knhc 282359
twoat
tropical weather outlook
nws tpc/national hurricane center miami fl
800 pm edt sun sep 28 2008

for the north atlantic...caribbean sea and the gulf of mexico...

The national hurricane center is issuing advisories on hurricane
kyle...located near the western tip of nova scotia canada.

Showers and thunderstorms have become a little more concentrated
near the center of a large non-tropical low pressure area located
over the central north atlantic ocean about 800 miles
west-southwest of the westernmost azores islands. This system
appears to be slowly acquiring tropical characteristics and it has
the potential to become a subtropical or tropical cyclone during
the next couple of days as it moves generally west or
west-northwestward at 10 to 15 mph.

Elsewhere...tropical cyclone formation is not expected during the
next 48 hours.

$$

forecaster brown

OH, my!
This season is starting to resemble the Energizer Bunny.

OMG! - It's RED!!!

Good chance it will be a fish, though, I think... Well, I hope so, anyway.

Well it is moving west northwest so lets hope for a right turn

I think it will

Wtnt42 knhc 290840
tcdat2
subtropical storm laura discussion number 1
nws tpc/national hurricane center miami fl al122008
500 am edt mon sep 29 2008

during the past 6 hours...conventional satellite imagery indicates
deep convection with cloud tops to near -70c has continued to
increase and has started wrapping around and very near the center
of the large non-tropical low pressure system located about 775 nmi
west of the westernmost azores islands. There is enough convection
near the center now for this system to be classified as a
subtropical storm. The 06z satellite classification from tafb was
st3.0/45 kt...but using the dvorak technique for a tropical system
yields nearly eight tenths banding...or t3.5/55 kt. So the initial
intensity is being set at 50 kt...which is consistent with a few
50-kt wind vectors noted in the northwest quadrant in a 28/2133z
quikscat hi-res overpass. However...since the time of that
overpass... Convection has increased markedly and is now the solid
band of convection in the southern semicircle. Therefore...it is
possible that the initial intensity could be a little higher than
currently indicated.

The initial motion estimate is 285/7. All of the nhc model guidance
is in good agreement on subtropical storm laura moving to the
west-northwest for the next 12 hours or so...and then turning
toward the northwest and north and accelerating as the incipient
mid-level circulation weakens and opens up into a trough and gets
lifted northward around the western periphery of a north-south
oriented mid-level ridge anchored over the azores islands. After
reaching the higher latitudes in about 72 hours...laura is forecast
to get picked by the fast westerlies and move quickly eastward as
an extratropical storm system.

Laura is expected to remain over 25c-26c ssts for the next 24 hours
and also be under light to moderate shear conditions. Therefore...
Some additional strengthening is forecast. However...if the current
trend of convection wrapping around the center continues...then
subtropical storm laura could quickly transition over to a tropical
cyclone and become a hurricane with a banding eye feature later
today. By 36 hours...laura is expected to be moving over much
cooler water...which should induce weakening along with a gradual
transition to extratropical status. The official intensity forecast
is a blend of the ships...gfdl...hwrf...and icon intensity models.

Forecast positions and max winds

initial 29/0900z 37.2n 47.3w 50 kt
12hr vt 29/1800z 38.0n 48.3w 55 kt
24hr vt 30/0600z 39.8n 48.9w 60 kt
36hr vt 30/1800z 41.7n 48.8w 60 kt...becoming extratropical
48hr vt 01/0600z 44.0n 48.0w 55 kt...extratropical
72hr vt 02/0600z 51.5n 44.0w 50 kt...extratropical
96hr vt 03/0600z 58.0n 34.5w 45 kt...extratropical
120hr vt 04/0600z 57.0n 21.5w 40 kt...extratropical

$$
forecaster stewart