Friday, October 27, 2017

POTENTIAL TROPICAL CYCLONE EIGHTEEN OCT 27, 2017 1053 PM EDT

...DISTURBANCE OVER THE NORTHWESTERN CARIBBEAN SEA GRADUALLY BECOMING BETTER ORGANIZED... 

000
WTNT33 KNHC 280240
TCPAT3

BULLETIN
Potential Tropical Cyclone Eighteen Advisory Number   2
NWS National Hurricane Center Miami FL       AL182017
1100 PM EDT Fri Oct 27 2017

...DISTURBANCE OVER THE NORTHWESTERN CARIBBEAN SEA GRADUALLY
BECOMING BETTER ORGANIZED...


SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...18.2N 84.4W
ABOUT 255 MI...415 KM SSW OF THE ISLE OF YOUTH
ABOUT 370 MI...595 KM SSW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...N OR 5 DEGREES AT 7 MPH...11 KM/H
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Isla de la Juventud, La Habana, Ciudad de la Habana, Matanzas,
Cienfuegos, and Villa Clara
* Northwestern Bahamas

A Tropical Storm Watch is in effect for...
* Central Bahamas

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, in this case within 36 hours.

Interests in the Cayman Islands, South Florida, and the Florida
Keys should monitor the progress of this system.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 1100 PM EDT (0300 UTC), the disturbance was centered near
latitude 18.2 North, longitude 84.4 West. The system is moving
toward the north near 7 mph (11 km/h).  A faster northward motion is
expected Saturday morning, followed by a faster motion toward the
northeast later on Saturday and Sunday. On the forecast track, the
system will move across western Cuba late Saturday and move through
the northwestern Bahamas Saturday night and early Sunday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Strengthening is forecast during the next 48 hours, and the system
is expected to become a tropical storm on Saturday.
* Formation chance through 48 hours...high...80 percent
* Formation chance through 5 days...high...80 percent

Tropical-storm-force winds extend outward up to 80 miles (130 km)
mainly to the south of the center.

The estimated minimum central pressure is 1005 mb (29.68 inches).


HAZARDS AFFECTING LAND
----------------------
RAINFALL: Potential Tropical Cyclone Eighteen is expected to produce
the following rainfall totals:

Northern Honduras: Additional 1 to 3 inches through Friday night.

The Cayman Islands, western and central Cuba, northern Bahamas: 4 to
8 inches with isolated maximum totals of 10 inches through Sunday.
These rainfall amounts may produce life threatening flash floods and
landslides.

South Florida, including the Keys: 2 to 4 inches with isolated
maximum totals of 6 inches through Sunday. These rainfall totals may
produce flash flooding, especially in urbanized areas.

WIND:  Tropical storm conditions are expected to first reach the
warning area in Cuba Saturday and the northwestern Bahamas Saturday
night.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 AM EDT.
Next complete advisory at 500 AM EDT.

$$
Forecaster Beven





 

POTENTIAL TROPICAL CYCLONE EIGHTEEN OCT 27, 2017 0500 PM EDT


000
WTNT33 KNHC 272044
TCPAT3

BULLETIN
Potential Tropical Cyclone Eighteen Advisory Number   1
NWS National Hurricane Center Miami FL       AL182017
500 PM EDT Fri Oct 27 2017

...TROPICAL STORM WARNINGS ISSUED FOR WESTERN CUBA AND THE
NORTHWESTERN BAHAMAS...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...17.5N 84.5W
ABOUT 305 MI...490 KM SSW OF THE ISLE OF YOUTH
ABOUT 415 MI...670 KM SSW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of Cuba has issued a Tropical Storm Warning for
the Cuban provinces of Isla de la Juventud, La Habana, Ciudad de la
Habana, Matanzas, Cienfuegos, and Villa Clara.

The government of the Bahamas has issued a Tropical Storm Warning
for the northwestern Bahamas, including the Abacos, Andros Island,
Berry Islands, Bimini, Eleuthera, Grand Bahama Island, and New
Providence.

The government of the Bahamas has issued a Tropical Storm Watch
for the central Bahamas, including Cat Island, the Exumas, Long
Island, Rum Cay, and San Salvador.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Isla de la Juventud, La Habana, Ciudad de la Habana, Matanzas,
Cienfuegos, and Villa Clara
* Northwestern Bahamas

A Tropical Storm Watch is in effect for...
* Central Bahamas

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, in this case within 36 hours.

Interests in the Cayman Islands, South Florida, and the Florida
Keys should monitor the progress of this system.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 500 PM EDT (2100 UTC), the disturbance was centered near latitude
17.5 North, longitude 84.5 West. The system is moving toward the
north-northwest near 6 mph (9 km/h). A faster northward motion is
expected to begin tonight, followed by a faster motion toward the
northeast on Saturday and Sunday. On the forecast track, the system
will move across western Cuba late Saturday and move through the
northwestern Bahamas Saturday night and early Sunday.

Data from an Air Force Reserve Hurricane Hunter aircraft indicate
that maximum sustained winds are near 40 mph (65 km/h) with higher
gusts. Some strengthening is forecast during the next 24 to 36
hours.

Environmental conditions are expected to be conducive for
development, and the system is likely to become a tropical storm
tonight or Saturday.
* Formation chance through 48 hours...high...80 percent
* Formation chance through 5 days...high...80 percent

Tropical-storm-force winds extend outward up to 80 miles (130 km),
mainly to the south of the center.

The estimated minimum central pressure based on data from the
aircraft is 1006 mb (29.71 inches).


HAZARDS AFFECTING LAND
----------------------
RAINFALL:  The system has the potential to produce the following
rainfall totals:

Northern Honduras:  Additional 1 to 3 inches through Friday night.
Cayman Islands, western and central Cuba and northwestern
Bahamas:  4 to 8 inches with maximum totals of 10 inches.

These rainfall amounts may produce life threatening flash floods and
mudslides.

South Florida including the Florida Keys:  3 to 5 inches, isolated
maximum of 8 inches possible.

These rainfall totals may produce flash flooding, especially in
urbanized areas.

WIND:  Tropical storm conditions are expected to first reach the
warning area in Cuba Saturday and the northwestern Bahamas Saturday
night.


NEXT ADVISORY
-------------
Next intermediate advisory at 800 PM EDT.
Next complete advisory at 1100 PM EDT.

$$
Forecaster Brennan
 


 

EYES ON THE TROPICS OCT 27, 2017 0339 PM EDT

000
ABNT20 KNHC 271719
TWOAT 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Fri Oct 27 2017

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

Showers and thunderstorms associated with a broad area of low
pressure located over the northwestern Caribbean Sea are beginning
to show signs of organization.  Environmental conditions are
expected to be conducive for additional development, and a tropical
depression or tropical storm is likely to form later today or
Saturday as the system moves northward over the northwestern
Caribbean Sea before turning northeastward by late Saturday.
Tropical storm watches and warnings may be needed for the Cayman
Islands, central and western Cuba, and the central and northwestern
Bahamas later today or tonight.  Interests in the Florida Keys and
South Florida should also monitor the progress of this disturbance.
An Air Force Reserve reconnaissance aircraft is en route to
investigate this system.

Regardless of development, this disturbance is expected to produce
locally heavy rainfall over the Cayman Islands, Jamaica, and
portions of Cuba during the next day or two.  Rainfall is also
forecast to spread northward across portions of South Florida and
the Keys on Saturday, and over the northwestern and central Bahamas
Saturday night and Sunday.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...80 percent.

$$
Forecaster Brown/Brennan
 

EYES ON THE TROPICS OCT 27, 2017 1004 PM EDT

000
ABNT20 KNHC 271123
TWOAT 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Fri Oct 27 2017

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

Shower and thunderstorm activity has increased and become more
concentrated in association with a trough of low pressure over the
northwestern Caribbean Sea.  Environmental conditions are expected
to be conducive for development today and Saturday, and a tropical
depression could form as the system moves northward over the
northwestern Caribbean Sea.  Increasing upper-level winds will make
conditions less favorable when the system moves north of Cuba and
merges with a cold front on Sunday.  Interests in the Cayman Islands
and central and western Cuba should monitor the progress of this
system.  Regardless of development, this disturbance is expected to
produce locally heavy rainfall over the Cayman Islands, Jamaica,
and portions of Cuba during the next day or two.  These rains are
forecast to spread northward across portions of South Florida and
the Keys on Saturday, and over the northwestern Bahamas Saturday
night and Sunday.  An Air Force Reserve reconnaissance aircraft is
scheduled to investigate this system this afternoon, if necessary.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 5 days...medium...60 percent.

$$
Forecaster Brown

 http://ralphstropicalweather.myfreesites.net


 SEVERE THUNDERSTORM OUTLOOK
 SPC AC 270524

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1224 AM CDT Fri Oct 27 2017

   Valid 281200Z - 291200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTH
   FLORIDA...

   ...SUMMARY...
   Thunderstorms with at least a marginal risk of severe weather may
   impact southern Florida and the Keys late Saturday afternoon and
   evening.

   ...South Florida...

   A positive-tilt synoptic trough currently from the upper MS Valley
   to the southern Rockies will undergo further amplification. By 12Z
   Saturday this feature will extend from the Great Lakes to the lower
   MS Valley and will advance slowly east during the day. Downstream
   cold front will stretch from a surface low over the Great Lakes to
   the central Gulf early Saturday and approach the Atlantic seaboard
   by the end of this period. Preceding the upper trough, a
   southern-stream perturbation accompanied by a weak surface low will
   emerge from the Caribbean. A warm front will lift north through
   southern FL in advance of the low with near 70F dewpoints spreading
   inland contributing to destabilization. However, instability will
   remain weak owing to widespread clouds and areas of
   showers/thunderstorms. Surface-2 km hodograph size will increase by
   early evening over south FL in vicinity of the warm front as the
   low-level jet strengthens in association with the approaching
   surface low, though winds aloft will remain modest. Given the moist
   boundary layer and favorable low-level wind profiles expected to
   evolve by Saturday evening, some potential exists for convection
   developing in this environment to produce a couple of brief
   tornadoes. The anticipated weak thermodynamic environment precludes
   more than a marginal risk category at this time. 
HYDROLOGIC OUTLOOK 
Event:Hydrologic Outlook
Alert:
...HEAVY RAINFALL POSSIBLE OVER SOUTH FLORIDA SATURDAY INTO 
SATURDAY NIGHT... 
 
A tropical disturbance over the Western Caribbean Sea is forecast 
by the National Hurricane Center (NHC) to move slowly north 
northeast and be near South Florida on Saturday. This disturbance 
will bring deep tropical moisture to the area leading to numerous 
showers and scattered thunderstorms with heavy rainfall, mainly 
Saturday and Saturday night. Total rainfall amounts are forecast 
to be between 2 to 4 inches with locally higher amounts with any 
training thunderstorms. If this trend continues for South Florida, 
then a Flood Watch may be needed later today or tonight for 
Saturday.
Instructions:
Target Area:
Coastal Broward County
Coastal Collier County
Coastal Miami Dade County
Coastal Palm Beach County
Far South Miami-Dade County
Glades
Hendry
Inland Broward County
Inland Collier County
Inland Miami-Dade County
Inland Palm Beach County
Mainland Monroe
Metro Broward County
Metro Palm Beach County
Metropolitan Miami Dade