Monday, August 6, 2018

TROPICAL OUTLOOK AUG 6, 2018... 0410 PM EDT

National Hurricane Center
155 
AXNT20 KNHC 061739
TWDAT 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
139 PM EDT Mon Aug 6 2018

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through 
1730 UTC.

...SPECIAL FEATURES...

Gale warning over the south-central Caribbean...

A strong ridge over the E CONUS extending E to Atlc adjacent waters
W of 60W will tighten the pressure gradient in the south-central 
Caribbean. Wind gusts reaching gale-force are expected starting 
tonight, then sustained gale-force winds are forecast for the 
Gulf of Venezuela on Tue night and along the coast of Colombia by 
Wed night. Please see the National Hurricane Center Atlantic High 
Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for 
further details. 

...TROPICAL WAVES...

A tropical wave is in the eastern Atlantic with axis extending 
from 07N-18N along 35W, moving W at 10 kt. This wave continues to
be affected by Saharan dry air and dust intrusion, which is 
limiting convection to the area where the wave meets the ITCZ from
09N-12N and west of 35W. 

A tropical wave is in the central Atlantic with axis extending 
from 01N-14N along 48W, moving W at about 10-15 kt. The wave 
continues to be affected by intrusion of Saharan dry air and dust
as indicated by GOES-16 RGBs, water vapor and CIRA LPW imagery at
the lower levels. Shallow moisture in the vicinity of the ITCZ 
supports scattered moderate convection mainly S of 10N. 

A tropical wave is in the E Caribbean with axis S of 21N along 
70W, moving W at 5-10 kt. The wave is in a very moist environment
at the lower levels as indicated by CIRA LPW and GOES-16 water 
vapor imagery. The wave is underneath a diffluent environment 
between an elongated upper-level low over the central basin and 
S-SW flow to the E, which is supporting scattered showers N of 
17N between 68W-72W.

A tropical wave is in the W Caribbean with axis S of 21N along 
80W, moving W at 10 kt. CIRA LPW imagery shows shallow moisture 
associated with the wave. Shallow moisture in the vicinity of the 
monsoon trough supports scattered moderate convection mainly S of 
10N.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the eastern Atlantic near 20N16W to 
14N31W. The ITCZ begins W of a tropical wave near 10N38W and 
continues to 08N46W, then resumes near 07N51W to 09N61W. Aside 
from the convection related to the tropical waves, scattered 
moderate convection is observed along the ITCZ. 

...DISCUSSION...

GULF OF MEXICO...

A broad area of high pressure extends from eastern CONUS across
the basin. A surface trough extends across the northwest Gulf
along 96W and north of 27N. Scattered moderate convection is
observed with this trough mainly north of 25N and west of 94W.
Another trough extends across the Bay of Campeche with scattered
showers. Return flow provided by the surface ridge continues to 
advect shallow moisture from the Caribbean and into the Gulf, 
which is supporting scattered moderate convection across the 
Yucatan Channel and south-central Gulf waters between 84W-90W. 
A third surface trough is in the far east Gulf from the Florida 
Big Bend to 29N84W with no significant convection at this time.

Expect for convection to continue across the west Gulf through 
tonight. Isolated showers are forecast in the Bay of Campeche 
through the middle of the week associated with a thermal surface 
trough that will come off the Yucatan Peninsula at night. This 
trough will also enhance the winds to fresh off the W Yucatan 
Peninsula. Surface ridging is forecast to prevail through the week.

CARIBBEAN SEA...

GOES-16 RGBs continue to show a thin layer of Saharan dust moving
across most of the basin where strong deep-layer wind shear 
prevails. This environment continues to suppress the development 
of significant convection across the basin. However, shallow 
moisture is across the basin supporting scattered showers within 
90 nm off the southwest of Cuba. To the south, the monsoon trough
supports similar convection within 75 nm off Panama. A tropical 
wave is in the W Caribbean lacking convection, while an upper-
level low over Hispaniola is supporting convection near the 
northern portion of the wave currently along 70W. See the 
Tropical Waves section above for further details. Fresh to near-
gale force winds in the south-central Caribbean are forecast to 
increase to gale-force gusts in the Gulf of Venezuela and off the 
coast of Colombia by tonight, then sustained gale-force winds 
will develop through midweek. See the Special Features section for
further details.

ATLANTIC OCEAN...

Two tropical waves are moving across the basin. Refer to the
section above for details. A non-tropical, surface low pressure 
system centered near 31N50W is interacting with a broad upper- 
level low. Although the system is producing disorganized showers and
thunderstorms to the east and northeast of the center, environmental
conditions are expected to be only marginally conducive for the low
to acquire subtropical or tropical characteristics while it moves
north or north-northeastward over the next day or so.  The low is
forecast to move over cooler waters by Tuesday night, and
development is not expected after that time. Southeast of this 
low, a surface trough extends from it to 26N57W supporting 
scattered showers and tstms N of 30N between 40W-50W. Aside from 
the tropical waves, the remainder of the Atlc is under the 
influence of surface high pressure that supports fair weather.


For additional information please visit 
http://www.hurricanes.gov/marine

$$

ERA
https://www.nhc.noaa.gov/ 
 
470 
ABNT20 KNHC 061740
TWOAT 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Mon Aug 6 2018

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

A non-tropical low pressure system centered about 1100 miles
west-southwest of the Azores is interacting with an upper-level low.
Although the associated shower and thunderstorm activity has
increased during the past 24 hours, environmental conditions are
expected to be only marginally conducive for additional development
while the system moves north or north-northeastward over the next
day or so.  The low is forecast to move over cooler waters Tuesday
night, and development is not expected after that time.  Additional
information on this system can be found in High Seas Forecasts
issued by the National Weather Service.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 5 days...low...30 percent.

&&
High Seas Forecasts issued by the National Weather Service can be
found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
on the Web at https://ocean.weather.gov/shtml/NFDHSFAT1.shtml.

$$
Forecaster Brown 
-----------------------------------------------------------------
 No change in the tropics.  Invest 97L has a chance for development
as it begins to track northeast away from present location.  97L
is only a threat to shipping... RTW 
 
Please note that the latest guidance model for 18z has not yet been
released.  So all I have is the 12z model run.  I may not be able to
post this evening, so click on image to go to NHC and tropical tidbits
for latest info and models...RTW 


TROPIC OUTLOOK AUG 6, 2018... 1011 AM EDT

National Hurricane Center
743 
AXNT20 KNHC 061149
TWDAT 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
749 AM EDT Mon Aug 6 2018

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through 
1145 UTC.

...SPECIAL FEATURES...

Gale warning in the south-central Caribbean...

A strong ridge over the E CONUS extending E to Atlc adjacent waters
W of 60W will tighten the pressure gradient in the south-central 
Caribbean early this week as a tropical wave moves W of
Hispaniola. Gale force winds are forecast for the Gulf of
Venezuela Tue night and along the coast of Colombia Wed night.
Please see the National Hurricane Center Atlantic High Seas 
Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for
further details. 

...TROPICAL WAVES...

A tropical wave is in the central Atlc with axis extending from 
07N-18N along 34W, moving W at 10-15 kt. CIRA LPW imagery show 
abundant shallow moisture in the wave environment. However, the 
wave continues to be affected by Saharan dry air and dust 
intrusion, which is limiting convection to isolated showers from 
10N-12N between 32W-37W. 

A tropical wave is in the central Atlc with axis extending from 
05N-16N along 46W, moving W at about 10 kt. The wave continues to
be severely affected by intrusion of Saharan dry air and dust as 
indicated by GOES-16 RGBs, water vapor and CIRA LPW imagery at the
lower levels. Shallow moisture in the vicinity of the ITCZ 
supports scattered moderate convection mainly S of 10N. 

A tropical wave is in the E Caribbean with axis S of 21N along 
70W, moving W at 5-10 kt. The wave is in a very moist environment
at the lower levels as indicated by CIRA LPW and GOES-16 water 
vapor imagery. The wave is underneath a diffluent environment 
between an elongated upper-level low over the central basin and 
S-SW flow to the E, which is supporting scattered showers N of 
16N between 65W-70W.

A tropical wave is in the W Caribbean with axis S of 21N along 
79W, moving W at 10 kt. CIRA LPW imagery shows shallow moisture 
associated with the wave. Shallow moisture in the vicinity of the
monsoon trough supports scattered moderate convection mainly S of
10N.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from 18N16W to 11N30W to 10N42W. The 
ITCZ begins W of a tropical wave near 07N48W and continues to 
08N55W to 09N59W. Aside from the convection related to the
tropical waves, scattered moderate convection is observed along
the monsoon trough between 37W-42 and along the ITCZ. 

...DISCUSSION...

GULF OF MEXICO...

The Bermuda high extends a ridge axis SW across the Florida
Peninsula to the SW Gulf of Mexico, where a weakness in the ridge
is analyzed as a surface trough from 28N95W to the Bay of Campeche
near 18N92W. Scattered showers prevail along the trough. Return 
flow provided by the ridge continues to advect shallow moisture 
from the Caribbean and SW N Atlc waters into the Gulf, which is 
supporting scattered moderate convection across the Yucatan 
Channel and south-central Gulf waters between 85W-88W. Another 
surface trough is in the far east Gulf from the Florida Big Bend 
to 31N84W to 26N84W with scattered showers. 

Expect for convection to continue across the west Gulf through 
tonight. Isolated showers are forecast in the Bay of Campeche 
through the middle of the week associated with a thermal surface 
trough that will come off the Yucatan Peninsula at night. This 
trough will also enhance the winds to fresh off the W Yucatan 
Peninsula. Surface ridging is forecast to prevail through the week.

CARIBBEAN SEA...

GOES-16 RGBs continue to show a thin layer of Saharan dust moving
across most of the basin where strong deep-layer wind shear 
prevails. This environment continues to suppress the development 
of significant convection in the region. However, shallow 
moisture is across the basin supporting scattered showers and 
tstms within 90 nm off the S coast of Cuba. The monsoon trough 
supports similar convection within 120 nm off southern Panama. A 
tropical wave is in the W Caribbean lacking convection while an 
upper-level low over the central basin supports scattered showers
in the vicinity of a tropical wave just W of the Mona Passage. 
See the tropical waves section for further details. Fresh to 
near-gale force winds in the south-central Caribbean are forecast
to increase to gale-force in the Gulf of Venezuela and off the 
coast of Colombia Wed and Thu, respectively. See the Special 
Features section for further details.

ATLANTIC OCEAN...

Two tropical waves are moving across the basin. Refer to the
section above for details. A non-tropical, surface low pressure 
system centered near 31N50W is interacting with a broad upper- 
level low. Although thunderstorm activity has increased near and 
to the east of the low-level center, environmental conditions are 
expected to be only marginally conducive for the low to acquire 
subtropical or tropical characteristics while it moves little over
the next day or so. By this afternoon, the low is expected to 
move toward the north or north-northeast and continue that motion 
through Tuesday. SE of this low, a surface trough extends from 
31N45W to 25N53W to 26N64W supporting scattered showers and tstms 
N of 29N between 43W-50W. Aside from the tropical waves, the 
remainder of the Atlc is under the influence of surface high 
pressure that supports fair weather.


For additional information please visit 
http://www.hurricanes.gov/marine

$$

Ramos/ERA
https://www.nhc.noaa.gov/
------------------------------------------------------------------
Other than INVEST 97L the tropics remain quiet... RTW
https://ralphstropicalweather.com/ 
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