| |
KF5JRV > WX 10.10.18 13:43l 193 Lines 8469 Bytes #999 (0) @ NA
BID : 22821_KF5JRV
Read: GUEST
Subj: NWS NHC Atlantic WX - Oct 10
Path: IW8PGT<CX2SA<HP2BWJ<XE1FH<JE7YGF<LU4ECL<VK4TUB<NA7KR<OK2PEN<VE2JOS<
N9LCF<KC8KPM<N9PMO<VE3UIL<AB0AF<KF5JRV
Sent: 181010/1115Z 22821@KF5JRV.#NWAR.AR.USA.NA BPQ6.0.16
000
WTNT43 KNHC 100834
TCDAT3
Hurricane Leslie Discussion Number 56
NWS National Hurricane Center Miami FL AL132018
500 AM AST Wed Oct 10 2018
Geostationary satellite and microwave images indicate that Leslie
has a large and ragged banded eye feature with deep convection most
organized over the northern semicircle. Since the Dvorak
classifications from TAFB and SAB are unchanged at 4.0/65 kt, the
initial wind speed is held at that value. Leslie has another day or
two to strengthen while it remains in low wind shear conditions and
over marginally warm waters. After that time, an increase in shear
and lower SSTs should cause Leslie to weaken. It is possible that
Leslie could become a post-tropical cyclone by day 5, but confidence
is not high on that occurring. The NHC intensity forecast is
largely an update of the previous one and it lies at the high end of
the model guidance.
Leslie is now moving southward at 9 kt in the flow on the southwest
side of a broad mid- to upper-level trough. A slower south-
southeastward motion is expected during the day today as the
trough pulls away. A turn to the east-northeast is expected tonight
as another trough approaches Leslie from the northwest, and that
motion with an increase in forward speed is expected through early
this weekend. After that time, the models are coming into better
agreement in showing Leslie being left behind and moving
southwestward on Sunday and Monday as a ridge builds to its
northwest. The NHC track forecast is adjusted southward at days 3
to 5 to be closer to the latest consensus aids. Although the
deterministic models are in better agreement this cycle, there is
still a lot of spread in the GFS and ECMWF ensemble members and
confidence in the track forecast remains fairly low.
FORECAST POSITIONS AND MAX WINDS
INIT 10/0900Z 28.6N 42.6W 65 KT 75 MPH
12H 10/1800Z 28.0N 42.3W 70 KT 80 MPH
24H 11/0600Z 28.1N 40.9W 75 KT 85 MPH
36H 11/1800Z 29.1N 38.3W 80 KT 90 MPH
48H 12/0600Z 30.5N 34.2W 75 KT 85 MPH
72H 13/0600Z 31.5N 25.0W 70 KT 80 MPH
96H 14/0600Z 30.5N 21.5W 50 KT 60 MPH
120H 15/0600Z 28.5N 23.5W 40 KT 45 MPH
$$
Forecaster Cangialosi
000
WTNT44 KNHC 100854
TCDAT4
Hurricane Michael Discussion Number 15
NWS National Hurricane Center Miami FL AL142018
400 AM CDT Wed Oct 10 2018
Reports from an Air Force Reserve Hurricane Hunter aircraft
indicate that Michael has continued to strengthen during the past
several hours. The maximum flight-level winds at 700 mb have been
136 kt, and the maximum surface wind estimates from the Stepped
Frequency Microwave Radiometer are in the 120-125 kt range. In
addition, the central pressure has fallen to near 943 mb. Based on
on the aircraft data, the initial intensity is increased to 120 kt.
This is a little below the satellite intensity estimates from TAFB,
SAB, and the CIMSS satellite consensus. The cirrus outflow
associated with Michael has improved over the past several hours,
with the outflow flowing into an upper-level low to the southeast
and along the east side of a large mid-latitude trough to the west.
The initial motion is 360/11. Michael is embedded in the flow
between a large mid- to upper-level ridge over the western Atlantic
and the northeastern United States and the aforementioned trough
across the central United States. These features should cause the
hurricane to turn north-northeastward during the next 12 h or so,
followed by a turn toward the northeast and a significant increase
in forward speed. Near the end of the forecast period, Michael or
its remnants should turn more eastward. The forecast track calls for
the eye to make landfall in the Florida Panhandle at about the 12 h
point, followed by a northeastward motion across the southeastern
United States between 12-48 h. The forecast guidance remains
tightly clustered, and the new forecast track is very close to the
previous track and the various consensus models through 72 h.
Additional strengthening is expected before landfall as Michael
remains over warm water and in an environment of light to moderate
vertical shear. After landfall, Michael is expected to steadily
weaken as it crosses the southeastern United States. Extratropical
transition is expected to begin while Michael is over land, and
this should be complete just after the 48 h point. The cyclone
should re-intensify due to baroclinic forcing as it moves rapidly
northeastward over the north Atlantic. The new intensity forecast
has been nudged upward at the landfall time based on current
trends. Otherwise, it is an update of the previous forecast.
Tropical storm conditions are expected to reach the hurricane
warning area during the next few hours, so all preparations should
be rushed to completion.
Key Messages:
1. Life-threatening storm surge is likely along portions of the
coasts of the Florida Panhandle, Big Bend, and Nature Coast, where
a storm surge warning is in effect. The worst storm surge is
expected between Tyndall Air Force Base and Keaton Beach, where 9 to
13 feet of inundation is possible.
2. Michael is likely to produce potentially catastrophic wind
damage where the core of the hurricane moves onshore in the Florida
Panhandle, and everyone in the hurricane warning area should
prepare for life-threatening hurricane winds. Dangerous hurricane-
force winds will also extend well inland across portions of the
Florida Panhandle, southern Georgia, and southeast Alabama as
Michael moves inland.
3. Heavy rainfall from Michael could produce life-threatening flash
flooding from the Florida Panhandle and Big Bend region into
portions of Georgia, the Carolinas, and southeast Virginia.
4. Tropical storm conditions will likely affect portions of the
southeast U.S. coast from northeast Florida through North Carolina,
and tropical storm watches and warnings are in effect for these
areas.
FORECAST POSITIONS AND MAX WINDS
INIT 10/0900Z 28.3N 86.5W 120 KT 140 MPH
12H 10/1800Z 29.9N 85.7W 125 KT 145 MPH
24H 11/0600Z 32.1N 83.8W 65 KT 75 MPH...INLAND
36H 11/1800Z 34.4N 80.5W 40 KT 45 MPH...INLAND
48H 12/0600Z 36.8N 75.6W 40 KT 45 MPH...OVER WATER
72H 13/0600Z 43.5N 59.5W 50 KT 60 MPH...POST-TROPTRATROP
96H 14/0600Z 49.5N 36.0W 55 KT 65 MPH...POST-TROPTRATROP
120H 15/0600Z 52.0N 17.5W 45 KT 50 MPH...POST-TROPTRATROP
$$
Forecaster Beven
000
WTNT45 KNHC 100835
TCDAT5
Tropical Storm Nadine Discussion Number 5
NWS National Hurricane Center Miami FL AL152018
500 AM AST Wed Oct 10 2018
Nadine continues to gradually strengthen. Microwave images indicate
that the storm is beginning to develop an inner core with a
concentrated area of deep convection noted in infrared satellite
imagery. The initial intensity is raised to 45 kt, in agreement
with 3.0/45 kt Dvorak classifications from TAFB and SAB. Nadine has
about another day to strengthen while it remains in favorable
atmospheric conditions of low wind shear and high moisture, and over
warm waters. The NHC intensity forecast follows the HCCA and IVCN
guidance and brings Nadine to 55 kt during that time period.
Thereafter, the global models all show a sharp increase in
southwesterly shear and that should end the opportunity for
strengthening and cause weakening. The combination of strong shear,
drier air, and slightly cooler SSTs should cause the cyclone to open
into a trough in 3 to 4 days, or perhaps even sooner.
The compact storm is moving north-northwestward at 6 kt, and the
center is a little to the right of the previous forecast track. A
continued northwest to north-northwest motion is expected during the
next couple of days while Nadine moves toward a trough over the
east-central Atlantic, the same trough that Leslie is embedded in.
After that time, the weak and shallow system should turn to the left
until dissipation. The NHC track forecast has been adjusted a
little to the right of the previous one due to the more northward
initial motion and position.
FORECAST POSITIONS AND MAX WINDS
INIT 10/0900Z 12.1N 31.1W 45 KT 50 MPH
12H 10/1800Z 12.8N 31.7W 50 KT 60 MPH
24H 11/0600Z 13.9N 32.5W 55 KT 65 MPH
36H 11/1800Z 15.1N 33.4W 45 KT 50 MPH
48H 12/0600Z 16.0N 34.7W 35 KT 40 MPH
72H 13/0600Z 17.3N 38.3W 25 KT 30 MPH
96H 14/0600Z...DISSIPATED
$$
Forecaster Cangialosi
73 de Scott KF5JRV
Pmail: KF5JRV@KF5JRV.#NWAR.AR.USA.NA
email: KF5JRV@ICLOUD.COM
Read previous mail | Read next mail
| |
