Issued at 1000 AM CDT Fri Oct 18 2019
000
WTNT41 KNHC 181455
TCDAT1
Potential Tropical Cyclone Sixteen Discussion Number 5
NWS National Hurricane Center Miami FL AL162019
1000 AM CDT Fri Oct 18 2019
The satellite presentation of the system features an area of very
deep convection with cloud tops colder than -80C within the eastern
part of a rather broad and elongated surface circulation seen in
visible satellite imagery and data from an Air Force Reserve
Hurricane Hunter aircraft. A NOAA Hurricane Hunter aircraft found
flight-level winds as high as 72 kt and SFMR winds of 45-50 kt
southeast of the ill-defined center, and based on these data the
initial intensity is set to 50 kt. The NOAA aircraft also measured a
pressure of around 1001 mb. While the cyclone has deepened, the
circulation is still quite elongated and not well defined, so the
system is maintained as a Potential Tropical Cyclone for now.
The global models continue to indicate that the circulation will
consolidate and the system will strengthen some during the next 12
hours or so, as the low-level circulation will be overtaken by an
upper-level trough currently situated over southwest Louisiana. The
system is still expected to become a tropical or subtropical storm
later today, with the exact phase dependent on the timing of the
circulation improving and the interaction with the upper trough.
Once the system moves inland, it should become extratropical by 36
hours and slowly weaken once it moves offshore of the Carolinas by
72-96 hours before dissipating by day 5. The new NHC intensity
forecast is adjusted upward from the previous one through 24 hours
based on the initial intensity and allows for the possibility of at
least some additional strengthening later today.
The initial motion is a somewhat uncertain 055/19 given the lack of
a well-defined center. The track model guidance remains in good
agreement on the system moving quickly northeastward toward the
northeastern Gulf Coast during the next 24 hours as it interacts
with the upper trough. After moving inland, a northeastward motion
is forecast to continue until after 48 hours, when an east-
northeastward motion is expected, which will take the circulation
offshore over the Atlantic by 72 hours. The new NHC track forecast
is similar to, but a bit to the south of the previous one and is
close to the various track consensus aids.
Regardless of the exact evolution of the system, portions of the
northeastern coast of the Gulf of Mexico will experience strong
winds, locally heavy rains, and storm surge later today and
Saturday. Similar impacts are expected across portions of the
Atlantic coast of the southeastern United States Saturday and
Sunday.
Key Messages:
1. There is a danger of life-threatening storm surge inundation of
up to 5 feet above ground level beginning later today along the
Florida Gulf Coast from Indian Pass to Clearwater Beach, where a
Storm Surge Warning is in effect. Residents in these areas should
follow advice given by local officials.
2. Tropical storm force winds are likely later today and tonight
along portions of the central and eastern Gulf Coast, where tropical
storm warnings are in effect. Regardless of the exact track and
intensity of the system, these winds will cover a large area,
especially east of the center.
3. Isolated flash flooding is possible along the central and
eastern Gulf Coast and the southeast United States coast through
Saturday night.
4. Wind and coastal flooding hazards along the U.S. East Coast will
be covered by non-tropical watches and warnings issued by local NWS
offices, since the system is expected to lose any tropical
characteristics after it moves inland along the Gulf Coast.
FORECAST POSITIONS AND MAX WINDS
INIT 18/1500Z 25.9N 90.0W 50 KT 60 MPH...POTENTIAL TROP CYCLONE
12H 19/0000Z 27.8N 88.0W 55 KT 65 MPH...TROPICAL STORM
24H 19/1200Z 29.9N 85.5W 50 KT 60 MPH
36H 20/0000Z 32.2N 82.5W 35 KT 40 MPH...POST-TROP/EXTRATROP
48H 20/1200Z 34.4N 78.5W 35 KT 40 MPH...POST-TROP/EXTRATROP
72H 21/1200Z 37.0N 71.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
96H 22/1200Z 37.0N 69.0W 25 KT 30 MPH...POST-TROP/EXTRATROP
120H 23/1200Z...DISSIPATED
$$
Forecaster Brennan
Continue reading...
000
WTNT41 KNHC 181455
TCDAT1
Potential Tropical Cyclone Sixteen Discussion Number 5
NWS National Hurricane Center Miami FL AL162019
1000 AM CDT Fri Oct 18 2019
The satellite presentation of the system features an area of very
deep convection with cloud tops colder than -80C within the eastern
part of a rather broad and elongated surface circulation seen in
visible satellite imagery and data from an Air Force Reserve
Hurricane Hunter aircraft. A NOAA Hurricane Hunter aircraft found
flight-level winds as high as 72 kt and SFMR winds of 45-50 kt
southeast of the ill-defined center, and based on these data the
initial intensity is set to 50 kt. The NOAA aircraft also measured a
pressure of around 1001 mb. While the cyclone has deepened, the
circulation is still quite elongated and not well defined, so the
system is maintained as a Potential Tropical Cyclone for now.
The global models continue to indicate that the circulation will
consolidate and the system will strengthen some during the next 12
hours or so, as the low-level circulation will be overtaken by an
upper-level trough currently situated over southwest Louisiana. The
system is still expected to become a tropical or subtropical storm
later today, with the exact phase dependent on the timing of the
circulation improving and the interaction with the upper trough.
Once the system moves inland, it should become extratropical by 36
hours and slowly weaken once it moves offshore of the Carolinas by
72-96 hours before dissipating by day 5. The new NHC intensity
forecast is adjusted upward from the previous one through 24 hours
based on the initial intensity and allows for the possibility of at
least some additional strengthening later today.
The initial motion is a somewhat uncertain 055/19 given the lack of
a well-defined center. The track model guidance remains in good
agreement on the system moving quickly northeastward toward the
northeastern Gulf Coast during the next 24 hours as it interacts
with the upper trough. After moving inland, a northeastward motion
is forecast to continue until after 48 hours, when an east-
northeastward motion is expected, which will take the circulation
offshore over the Atlantic by 72 hours. The new NHC track forecast
is similar to, but a bit to the south of the previous one and is
close to the various track consensus aids.
Regardless of the exact evolution of the system, portions of the
northeastern coast of the Gulf of Mexico will experience strong
winds, locally heavy rains, and storm surge later today and
Saturday. Similar impacts are expected across portions of the
Atlantic coast of the southeastern United States Saturday and
Sunday.
Key Messages:
1. There is a danger of life-threatening storm surge inundation of
up to 5 feet above ground level beginning later today along the
Florida Gulf Coast from Indian Pass to Clearwater Beach, where a
Storm Surge Warning is in effect. Residents in these areas should
follow advice given by local officials.
2. Tropical storm force winds are likely later today and tonight
along portions of the central and eastern Gulf Coast, where tropical
storm warnings are in effect. Regardless of the exact track and
intensity of the system, these winds will cover a large area,
especially east of the center.
3. Isolated flash flooding is possible along the central and
eastern Gulf Coast and the southeast United States coast through
Saturday night.
4. Wind and coastal flooding hazards along the U.S. East Coast will
be covered by non-tropical watches and warnings issued by local NWS
offices, since the system is expected to lose any tropical
characteristics after it moves inland along the Gulf Coast.
FORECAST POSITIONS AND MAX WINDS
INIT 18/1500Z 25.9N 90.0W 50 KT 60 MPH...POTENTIAL TROP CYCLONE
12H 19/0000Z 27.8N 88.0W 55 KT 65 MPH...TROPICAL STORM
24H 19/1200Z 29.9N 85.5W 50 KT 60 MPH
36H 20/0000Z 32.2N 82.5W 35 KT 40 MPH...POST-TROP/EXTRATROP
48H 20/1200Z 34.4N 78.5W 35 KT 40 MPH...POST-TROP/EXTRATROP
72H 21/1200Z 37.0N 71.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
96H 22/1200Z 37.0N 69.0W 25 KT 30 MPH...POST-TROP/EXTRATROP
120H 23/1200Z...DISSIPATED
$$
Forecaster Brennan
Continue reading...