Thread: Hurricane Maria SSW of Newfoundland

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INVEST, AL, L, , , , , 95, 2011, DB, O, 2011090506, 9999999999, , , , , , METWATCH, , AL952011
AL, 95, 2011090406, , BEST, 0, 90N, 236W, 20, 1011, DB, 0, , 0, 0, 0, 0,
AL, 95, 2011090412, , BEST, 0, 90N, 249W, 20, 1011, DB, 0, , 0, 0, 0, 0,
AL, 95, 2011090418, , BEST, 0, 90N, 261W, 20, 1010, DB, 0, , 0, 0, 0, 0,
AL, 95, 2011090500, , BEST, 0, 90N, 273W, 20, 1010, DB, 0, , 0, 0, 0, 0,
AL, 95, 2011090506, , BEST, 0, 90N, 285W, 20, 1009, DB

Tropical weather outlook
nws national hurricane center miami fl
800 am edt mon sep 5 2011

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

The national hurricane center is issuing advisories on hurricane
katia...located about 605 miles south-southeast of bermuda.

A vigorous tropical wave located about 500 miles southwest of the
cape verde islands is producing a large area of cloudiness and
thunderstorms. Environmental conditions are conducive for some
development of this system over the next few days as it moves
westward at about 15 mph. This system has a low chance...20
percent...of becoming a tropical cyclone during the next 48 hours.

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

$$
forecaster stewart

A VIGOROUS TROPICAL WAVE...ACCOMPANIED BY A BROAD SURFACE LOW
PRESSURE SYSTEM...IS LOCATED ABOUT 550 MILES SOUTHWEST OF THE
CAPE VERDE ISLANDS. THIS LARGE DISTURBANCE HAS BECOME MUCH BETTER
ORGANIZED DURING THE PAST SEVERAL HOURS...AND ENVIRONMENTAL
CONDITIONS ARE EXPECTED TO REMAIN CONDUCIVE FOR A TROPICAL
DEPRESSION TO FORM DURING THE NEXT DAY OR SO. THIS SYSTEM HAS A
HIGH CHANCE...60 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS AS IT MOVES WESTWARD TO WEST-NORTHWESTWARD AT
ABOUT 15 MPH.

Tropical depression fourteen forecast/advisory number 1
nws national hurricane center miami fl al142011
2100 utc tue sep 06 2011


tropical depression center located near 11.8n 37.0w at 06/2100z
position accurate within 30 nm

present movement toward the west-northwest or 285 degrees at 16 kt

estimated minimum central pressure 1008 mb
max sustained winds 30 kt with gusts to 40 kt.
Winds and seas vary greatly in each quadrant. Radii in nautical
miles are the largest radii expected anywhere in that quadrant.

Repeat...center located near 11.8n 37.0w at 06/2100z
at 06/1800z center was located near 11.6n 36.2w

forecast valid 07/0600z 12.3n 39.6w
max wind 35 kt...gusts 45 kt.
34 kt... 40ne 0se 0sw 40nw.

Forecast valid 07/1800z 12.9n 43.8w
max wind 40 kt...gusts 50 kt.
34 kt... 40ne 0se 0sw 40nw.

Forecast valid 08/0600z 13.7n 47.5w
max wind 45 kt...gusts 55 kt.
34 kt... 50ne 25se 25sw 50nw.

Forecast valid 08/1800z 14.5n 50.7w
max wind 50 kt...gusts 60 kt.
50 kt... 25ne 0se 0sw 25nw.
34 kt... 75ne 20se 25sw 75nw.

Forecast valid 09/1800z 16.0n 57.0w
max wind 55 kt...gusts 65 kt.
50 kt... 25ne 0se 0sw 25nw.
34 kt... 75ne 20se 25sw 75nw.

Extended outlook. Note...errors for track have averaged near 175 nm
on day 4 and 225 nm on day 5...and for intensity near 20 kt each day

outlook valid 10/1800z 17.0n 62.0w
max wind 60 kt...gusts 75 kt.

Outlook valid 11/1800z 19.5n 66.5w
max wind 65 kt...gusts 80 kt.

Request for 3 hourly ship reports within 300 miles of 11.8n 37.0w

next advisory at 07/0300z

$$
forecaster avila

bulletin
tropical depression fourteen advisory number 1
nws national hurricane center miami fl al142011
500 pm ast tue sep 06 2011

...new tropical depression forms in the far eastern atlantic...


Summary of 500 pm ast...2100 utc...information
----------------------------------------------
location...11.8n 37.0w
about 920 mi...1480 km wsw of the cape verde islands
about 1650 mi...2655 km e of the lesser antilles
maximum sustained winds...35 mph...55 km/h
present movement...wnw or 285 degrees at 18 mph...30 km/h
minimum central pressure...1008 mb...29.77 inches


watches and warnings
--------------------
there are no coastal watches or warnings in effect.


Discussion and 48-hour outlook
------------------------------
at 500 pm ast...2100 utc...the center of newly formed tropical
depression fourteen was located near latitude 11.8 north...
Longitude 37.0 west. The depression is moving toward the
west-northwest near 18 mph...30 km/h...and this general motion is
expected to continue during the next two days.

Maximum sustained winds are near 35 mph...55 km/h...with higher
gusts. Some strengthening is forecast during the next 48 hours and
the depresion could become a tropical storm tonight or wednesday.

Estimated minimum central pressure is 1008 mb...29.77 inches.


Hazards affecting land
----------------------
none


next advisory
-------------
next complete advisory...1100 pm ast.

$$
forecaster avila


tropical depression fourteen discussion number 1
nws national hurricane center miami fl al142011
500 pm edt tue sep 06 2011

satellite images indicate that a tropical depression has formed
within the area of disturbed weather in the far eastern atlantic.
There has been an increase in the organized convection primarily in
bands to the north and west of the center...and the upper-level
outflow is well established primarily in the western semicircle.
Dvorak t-numbers from tafb and sab have increased to 2.0 on the
dvorak scale leading to an initial intensity of 30 knots. Satellite
images show that the depression is currently on a developing
trend...but global models indicate that the upper-level winds are
only marginally favorable for strengthening along the path of the
cyclone. The official forecast calls for gradual intensification...
Following the lgem model. None of the guidance suggest significant
strengthening...but the depression is expected to be a hurricane as
it nears the leeward islands.

Since the depression has just formed and we did not have a well
defined center before...the initial motion is uncertain. It appears
that the depression is moving toward the west-northwest at 16 knots
on the south side of the atlantic subtropical ridge. This pattern
is forecast to persist...so this general motion with a gradual
decrease in forward speed is expected through five days. The track
guidance is uncertain with the gfs moving the cyclone very fast on
a west-northwest to northwestward track...and the ecmwf a little
slower and farther to the south. However...it appears that these
two reliable models are gradually coming into better agreement.
The official forecast track is biased a little slower toward the
ecmwf.


Forecast positions and max winds

init 06/2100z 11.8n 37.0w 30 kt 35 mph
12h 07/0600z 12.3n 39.6w 35 kt 40 mph
24h 07/1800z 12.9n 43.8w 40 kt 45 mph
36h 08/0600z 13.7n 47.5w 45 kt 50 mph
48h 08/1800z 14.5n 50.7w 50 kt 60 mph
72h 09/1800z 16.0n 57.0w 55 kt 65 mph
96h 10/1800z 17.0n 62.0w 60 kt 70 mph
120h 11/1800z 19.5n 66.5w 65 kt 75 mph

$$
forecaster avila

I don't like that blue line

I don't like the CONE, either:

Tropical depression fourteen discussion number 3
nws national hurricane center miami fl al142011
500 am ast wed sep 07 2011

data from an earlier ascat pass suggested that the cyclone was near
tropical storm strength. However...the cloud pattern has not become
significantly better organized and dvorak t-numbers from both
agencies are 2.0...which do not support naming the system at this
time. Normally we would expect significant strengthening of a
tropical cyclone in this location at this time of year. Most of the
intensity guidance...however...does not call for much of an increase
in strength for the next 72 hours or so. The reasons for this are
not clear...but water vapor imagery does show a weak upper-level
trough or shear axis about 500 miles to the northwest of the
depression...and this could be an inhibiting factor. Late
in the forecast period...the gfdl model shows considerable
intensification...but it is one of few models to do so. The nhc
intensity forecast is above the operational model consensus but
quite close to a consensus that includes the hurricane forecast
improvement project...hfip...models. This is also the same as the
previous official wind speed forecast.

There has been some scatter in the center fixes...but a smoothed
estimate of the initial motion is 280/17. Over the next day or
two...the tropical cyclone will be moving to the south of a
strengthening subtropical ridge which is likely to cause some
additional increase in forward speed. By days 2-3...however...the
ridge begins to weaken and the cyclone should begin a gradual turn
to the right with decreasing forward speed. The track guidance
continues to show quite a bit of spread...with the gfdl and gfs
among the fastest of the models and the ecmwf and hwrf
significantly slower. The official forecast for this package is
only slightly faster than the previous one and near or a little to
the left of the multi-model consensus.

Forecast positions and max winds

init 07/0900z 12.0n 39.9w 30 kt 35 mph
12h 07/1800z 12.6n 42.7w 35 kt 40 mph
24h 08/0600z 13.3n 46.8w 40 kt 45 mph
36h 08/1800z 14.0n 51.0w 45 kt 50 mph
48h 09/0600z 14.6n 54.5w 50 kt 60 mph
72h 10/0600z 16.7n 60.5w 55 kt 65 mph
96h 11/0600z 19.5n 65.5w 60 kt 70 mph
120h 12/0600z 22.5n 69.5w 65 kt 75 mph

$$
forecaster pasch