| |
KF5JRV > WX 12.10.18 12:44l 161 Lines 6520 Bytes #999 (0) @ NA
BID : 22936_KF5JRV
Read: GUEST
Subj: NWS NHC Atlantic WX - Oct 12
Path: IW8PGT<CX2SA<SV1CMG<PI8BDG<AB0AF<KF5JRV
Sent: 181012/1124Z 22936@KF5JRV.#NWAR.AR.USA.NA BPQ6.0.16
000
WTNT43 KNHC 120911
TCDAT3
Hurricane Leslie Discussion Number 64
NWS National Hurricane Center Miami FL AL132018
500 AM AST Fri Oct 12 2018
Leslie has changed little in organization since the last advisory.
The eye is currently not apparent in conventional satellite imagery,
although recent microwave overpasses indicate at least a partial
eyewall is present under the overcast. Satellite intensity
estimates have changed little, so the initial intensity is held at
80 kt.
The initial motion is now 065/24. The guidance is in good
agreement that this general motion should continue for 24 h or so.
After that, there is a major model divergence. The GFS, ECMWF, and
the various consensus models now show a continued east-northeast
motion until landfall in Portugal or Spain. On the other hand, the
UKMET, UK ensemble mean, and Canadian models show a turn toward the
south and then back to the west. Since the previous forecast showed
a southward and westward turn, the new forecast track will also
follow this scenario. However, it is shifted well to the east of
the previous track due to the forecasts of the other models.
Needless to say, the latter portion of the track forecast is low
confidence.
Leslie should gradually weaken as it approaches Madeira Island
during the next 24-36 h. After that, the intensity forecast is
dependent on what track the cyclone takes. If it follows the
GFS/ECMWF scenario, the system would likely make landfall on the
Iberian peninsula and quickly dissipate. If it follows the UKMET
scenario, a combination of shear, cool water, and dry air
entrainment should cause weakening. Since the track forecast is
closer to the UKMET scenario, the intensity forecast follows the
previous forecast in having Leslie decay to a post-tropical low by
72 h. However, this is also a low confidence forecast due to the
uncertainties in the track forecast.
FORECAST POSITIONS AND MAX WINDS
INIT 12/0900Z 31.9N 31.0W 80 KT 90 MPH
12H 12/1800Z 33.1N 26.5W 80 KT 90 MPH
24H 13/0600Z 34.2N 20.3W 75 KT 85 MPH
36H 13/1800Z 34.6N 15.5W 65 KT 75 MPH
48H 14/0600Z 34.0N 13.0W 50 KT 60 MPH
72H 15/0600Z 32.0N 12.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 16/0600Z 30.0N 13.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 17/0600Z 28.0N 18.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
$$
Forecaster Beven
000
WTNT44 KNHC 120848
TCDAT4
Post-Tropical Cyclone Michael Discussion Number 23
NWS National Hurricane Center Miami FL AL142018
500 AM EDT Fri Oct 12 2018
Satellite imagery and surface observations indicate that Michael has
become a storm-force extratropical low as it moves off of the coast
of the United States. The initial intensity has been increased to
55 kt based on the surface observations, and some additional
increase in strength is expected during the next 12-24 h. After
that time, the cyclone should gradually weaken, and it is forecast
to dissipate over the eastern Atlantic by 96 h. The revised
intensity and size forecast are based mainly on the guidance from
the Ocean Prediction Center.
The initial motion is 065/25. The cyclone should move very rapidly
toward the east-northeast, followed by a more eastward motion near
the end of the cyclone's life.
This is the last public advisory issued by the National Hurricane
Center on this system. Additional information on this system can be
found in High Seas Forecasts issued by the National Weather Service,
under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and available
on the Web at https://ocean.weather.gov/shtml/NFDHSFAT1.shtml.
Additional information on the remaining impacts over the United
States can be found in products issued by local National Weather
Service forecast offices.
Key Messages:
1. Heavy rainfall may lead to flash flooding this morning from
eastern New Jersey to southern New England. Elsewhere high water,
flooding, and flash flooding may persist today where heavy rain fell
very recently in the Carolinas and Mid-Atlantic states.
2. Gale-force winds will continue for a few more hours over
portions of southeastern Virginia, the southern Chesapeake Bay, and
the Delmarva Peninsula.
FORECAST POSITIONS AND MAX WINDS
INIT 12/0900Z 38.0N 73.1W 55 KT 65 MPH...POST-TROPTRATROP
12H 12/1800Z 40.4N 66.8W 60 KT 70 MPH...POST-TROPTRATROP
24H 13/0600Z 43.8N 55.5W 60 KT 70 MPH...POST-TROPTRATROP
36H 13/1800Z 46.2N 42.0W 55 KT 65 MPH...POST-TROPTRATROP
48H 14/0600Z 47.0N 28.5W 50 KT 60 MPH...POST-TROPTRATROP
72H 15/0600Z 46.0N 11.0W 35 KT 40 MPH...POST-TROPTRATROP
96H 16/0600Z...DISSIPATED
$$
Forecaster Beven
000
WTNT45 KNHC 120846
TCDAT5
Tropical Storm Nadine Discussion Number 13
NWS National Hurricane Center Miami FL AL152018
500 AM AST Fri Oct 12 2018
A 0353 UTC AMSR-2 microwave overpass and GOES-16 shortwave infrared
imagery show that the 30-40 kt of west-southwesterly shear, depicted
in the UW-CIMSS shear analysis, is partially exposing, or
decoupling, Nadine's surface circulation from the convective mass.
The cloud pattern, however, hasn't changed during the past 6 hours
and in fact, the cloud top temperatures in the curved band over the
north semicircle have decreased somewhat. TAFB and SAB satellite
intensity estimates remained unchanged, and the initial intensity is
held at 45 kt.
The Decay SHIPS statistical intensity model indicates that the shear
will persist and increase a little more which should cause Nadine to
spin down and dissipate in 48 hours, or possibly sooner. The
large-scale models all show the cyclone opening up into a trough of
low pressure and ultimately dissipating over the deep tropical
central Atlantic at that time. The official forecast follows suit
and is an update of the previous advisory.
The initial motion is estimated to be west-northwestward, or 295/7
kt. A low to mid-level ridge anchored between Nadine to the south
and Hurricane Leslie to the north, should steer the cyclone
west-northwestward and then westward at an accelerated pace until
dissipation. The NHC forecast has again been adjusted a little
south and toward both the NOAA-HCCA and TVCN consensus models.
FORECAST POSITIONS AND MAX WINDS
INIT 12/0900Z 15.2N 35.5W 45 KT 50 MPH
12H 12/1800Z 15.4N 37.2W 40 KT 45 MPH
24H 13/0600Z 15.6N 39.7W 30 KT 35 MPH
36H 13/1800Z 15.8N 42.7W 30 KT 35 MPH
48H 14/0600Z...DISSIPATED
$$
Forecaster Roberts
73 de Scott KF5JRV
Pmail: KF5JRV@KF5JRV.#NWAR.AR.USA.NA
email: KF5JRV@ICLOUD.COM
Read previous mail | Read next mail
| |
