Tropical Report

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Sun Sep 17 2017

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Hurricane
Jose, located several hundred miles south-southeast of Cape
Hatteras, North Carolina, on Tropical Storm Lee, located over the
eastern Atlantic Ocean, and on Tropical Storm Maria, located several
hundred miles east-southeast of the Lesser Antilles.

Tropical cyclone formation is not expected during the next 5 days.

&&

Public Advisories on Tropical Storm Maria are issued under WMO
header WTNT35 KNHC and under AWIPS header MIATCPAT5.
Forecast/Advisories on Tropical Storm Maria are issued under WMO
header WTNT25 KNHC and under AWIPS header MIATCMAT5.

$$
Forecaster Cangialosi

JOSE MOVING A LITTLE FASTER NORTHWARD WITH NO CHANGE IN STRENGTH… …DANGEROUS SURF AND RIP CURRENTS EXPECTED ALONG THE EAST COAST OF THE UNITED STATES

Hurricane Jose Discussion Number 48
NWS National Hurricane Center Miami FL AL122017
500 AM EDT Sun Sep 17 2017

The satellite presentation of Jose continues to reveal little
change in the overall cloud structure since yesterday afternoon.
The 25-30 kt of westerly shear is inhibiting any further development
of the inner core. Cloud tops have warmed near the center and the
cyclone appears to be tilted toward the northeast with height
in earlier microwave images. Dvorak satellite intensity estimates
remain unchanged from the last advisory, and the initial
intensity is held at 70 kt. Due to the expected shear persisting
through the entire forecast period, the statistical and dynamical
intensity guidance no longer indicate any hint of strengthening,
even in the short term. Accordingly, The NHC forecast reflects
little change in strength through the 48 hour period, then
shows gradual weakening through 5 days.

The initial motion is estimated to be northward, or 360/7 kt. The
cyclone is expected to continue on this northward track, along the
western periphery of the Bermuda high, through 48 hours.
Afterward, Jose should gradually turn north-northeastward to
northeastward on days 3 and 4. Near the end of the forecast
period, Jose is forecast to slowly turn eastward within the
mid-latitude, mid-level westerly flow associated with shortwave
trough moving over the Canadian Maritimes. The official forecast
has been adjusted slightly to the west, closer to the HFIP
Corrected Consensus, and near a blend of the UKMET, and ECMWF which
have also shifted a bit westward.

KEY MESSAGES:

1. The center of Jose is forecast to pass well east of the North
Carolina coast on Monday, and tropical-storm-force winds are
currently expected to remain offshore of the North Carolina Outer
Banks. However, an additional increase in the size of the storm or a
westward adjustment in the track forecast could bring tropical storm
conditions closer to the Outer Banks, and interests there should
monitor the progress of Jose through Monday.

2. While Jose is currently forecast to remain offshore of the U.S.
coast from Virginia northward to New England, the large cyclone
could cause some direct impacts to these areas and any deviation to
the left of the NHC forecast track would increase the likelihood and
magnitude of those impacts. Interests along the U.S. east coast
from Virginia to New England should monitor the progress of Jose
through the next several days.

3. Swells generated by Jose are affecting Bermuda, the Bahamas, the
northern coasts of Hispaniola and Puerto Rico, and much of the U.S.
east coast. These swells are likely to cause dangerous surf and rip
current conditions for the next several days in these areas.

FORECAST POSITIONS AND MAX WINDS

INIT 17/0900Z 30.0N 71.7W 70 KT 80 MPH
12H 17/1800Z 31.0N 71.6W 70 KT 80 MPH
24H 18/0600Z 32.5N 71.5W 70 KT 80 MPH
36H 18/1800Z 34.0N 71.5W 65 KT 75 MPH
48H 19/0600Z 35.6N 71.3W 65 KT 75 MPH
72H 20/0600Z 38.6N 70.2W 60 KT 70 MPH
96H 21/0600Z 40.0N 67.4W 50 KT 60 MPH
120H 22/0600Z 39.8N 64.8W 45 KT 50 MPH

$$
Forecaster Roberts

 

LEE MOVING SLOWLY WESTWARD OVER THE OPEN EASTERN ATLANTIC

Tropical Storm Lee Discussion Number 10
NWS National Hurricane Center Miami FL AL142017
500 AM AST Sun Sep 17 2017

Lee remains sheared this morning, with the center of circulation
just beneath the northern edge of the cloud mass. Consequently, the
initial intensity is held at 35 kt and agrees with the subjective
Dvorak intensity estimates from TAFB and SAB. The cyclone is
forecast to remain in an upper wind environment of strong
west-northwesterly shear through the forecast period. The global
and statistical models all show no intensification of Lee through 36
hours or so, followed by a gradual weakening trend through day 5.
In fact, the GFS and ECMWF show dissipation in less than 4 days.
Only the HWRF hurricane model indicates modest strengthening around
the 48 hour period. The official forecast is similar to the
previous package and reflects Lee degenerating into a remnant low in
4 days.

The initial motion is estimated to be westward, or 280/6 kt. The
cyclone is currently moving within the easterly mid-level flow
produced by a subtropical ridge anchored to the north. This ridge
is forecast to erode in 36 hours, allowing Lee to gradually turn
west-northwestward and continue tracking in this fashion through 5
days. A slight adjustment to the right of the previous advisory was
made to lie more closely to the HCCA technique and a blend of the
ECMWF and GFS global models.

FORECAST POSITIONS AND MAX WINDS

INIT 17/0900Z 13.0N 35.4W 35 KT 40 MPH
12H 17/1800Z 13.1N 36.4W 35 KT 40 MPH
24H 18/0600Z 13.4N 37.9W 35 KT 40 MPH
36H 18/1800Z 14.2N 39.7W 35 KT 40 MPH
48H 19/0600Z 15.0N 41.3W 30 KT 35 MPH
72H 20/0600Z 17.1N 44.7W 30 KT 35 MPH
96H 21/0600Z 18.9N 48.4W 25 KT 30 MPH…POST-TROP/REMNT LOW
120H 22/0600Z 20.3N 52.3W 20 KT 25 MPH…POST-TROP/REMNT LOW

$$
Forecaster Roberts

 

MARIA EXPECTED TO BECOME A HURRICANE LATER TODAY

Tropical Storm Maria Discussion Number 4
NWS National Hurricane Center Miami FL AL152017
500 AM AST Sun Sep 17 2017

Maria’s cloud pattern is becoming better organized with developing
convective banding features and a gradually expanding CDO.
Upper-level outflow is only slightly restricted over the southern
portion of the circulation. The current intensity is set at 55
kt, in agreement with the latest Dvorak estimates from both TAFB and
SAB. The environment should be conducive for continued
strengthening for the next several days with low shear, a warm
ocean and a fairly moist mid-tropospheric air mass. The official
intensity forecast follows the model consensus, but a more rapid
intensification than indicated here is certainly possible over the
next couple of days.

Latest center fixes indicate that the tropical cyclone is now
moving west-northwestward, or 285/13 kt. A mid-level high pressure
area to the north of Maria is forecast to weaken slightly over the
next several days. This should result in a continued
west-northwestward motion with a slowing of forward speed. The
official track forecast is a blend of the latest GFS and ECMWF
predictions, and lies on the left side of the guidance envelope.

KEY MESSAGES:

1. Maria is expected to strengthen and affect portions of the
Leeward Islands as a hurricane early next week, bringing dangerous
wind, storm surge and rainfall hazards. Hurricane or Tropical
Storm Warnings will likely be required for portions of these
islands today.

2. Maria could also affect the British and U.S. Virgin Islands and
Puerto Rico by mid week as a dangerous major hurricane, and
hurricane watches could be issued for these islands as early as
tonight. Interests in these areas should monitor the progress of
Maria and follow any advice given by local officials.

FORECAST POSITIONS AND MAX WINDS

INIT 17/0900Z 13.0N 54.9W 55 KT 65 MPH
12H 17/1800Z 13.7N 56.5W 65 KT 75 MPH
24H 18/0600Z 14.5N 58.3W 75 KT 85 MPH
36H 18/1800Z 15.2N 60.0W 85 KT 100 MPH
48H 19/0600Z 15.8N 61.3W 95 KT 110 MPH
72H 20/0600Z 17.0N 64.0W 110 KT 125 MPH
96H 21/0600Z 18.4N 67.0W 100 KT 115 MPH…INLAND
120H 22/0600Z 19.5N 69.5W 105 KT 120 MPH…OVER WATER

$$
Forecaster Pasch