TROPICAL WEATHER OUTLOOK SEPT 21, 2018

The tropical Atlantic looking busy again however, only a few systems have a chance for development.

Invest 99L off the African coast is looking rather impressive on visible satellite and on color image this morning.  The system has a nice outflow and color image shows very cold cloud tops a sign that this system is becoming better organized.  A depression or tropical storm can form at anytime.

This system has a LOW chance 20% within 48 hrs and a MED chance 60% within 5-days.  The chance for development more than likely increase later today because the system continues to show signs of organization...RTW

Invest 98L southeast of Bermuda the remnants of Florence is void of thunderstorms.  This system is forecast to loop back toward the coast and recurve out to sea.  I dont see much development with this system at this time.  Chance for development is LOW 0% within 48 hrs and LOW 20% with 5-days...RT

Invest 97L has an exposed circulation to the west-northwest of the thunderstorms. This system is presently passing through a shear environment with upper level shear from the west seperating the thunderstorms the east and away from circulation.  Development if any will be slow to occur.  Chances for development are LOW 10% within 48 hrs and LOW 10% within 5-days... RTW

There are watching a non-tropical low pressure in the north Atlantic bewteen Bermuda and the Azores that has LOW chance 10% within 48 hrs and a HIGH chance 70% within 5-days.  Not much going on here now but there is a frontal boundary where a low could form from...RTW

TROPICAL WEATHER OUTLOOK SEPT 20, 2018... 0322 PM EDT

Invest 97L not looking as well define as earlier.  In fact this system seems to be in a shear environment and dry air is also interacting with this 97L.  Chances for development are still low and have dropped to 10% within 48 hrs and within 5-days.

Invest 98L has not yet developed but most of the models suggesting development from this system over the north Central Atlantic in the coming days.  This system has a MED chance 50% within 5- days.  No a threat to land a fish storm!

Another area of investigation will emerge off the African coast In a day or so.  That has a LOW chance 0% within 48 hrs and 20% within 5-days.

An area of low pressure near Bermuda more than likely the remnants of Florence seems to be getting better organized and is forecast to turn back toward the Eastern seaboard and maybe brush the coast as it turns north and east.

I will continue to monitor the Caribbean for development in the coming weeks...RTW

REMNANT LOW FROM FLORENCE LOOKING WELL ORGANIZED

REMNANT low from what use to be Florence is looking somewhat organized.  Center is slighly exposed but it seems like it wants to reform.  It is presently being pulled by a frontal boundary.  Some models show a loop back toward the Eastern seaboard and a loop back north and northeast along the coast.  Questionable but I will watch it...RTW

TROPICAL WEATHER UPDATE SEPT 20, 2018

Still monitoring two systems that NHC has as invest 97L and 98L.

97L has a LOW chance 20% within 48 hrs and within 5-days.  This system is showing signs of development as we speak.  Thunderstorm activity has increased and the system seems to have a nice circulation associated with it.

This system if it does develop tropically it will more than likely be short lived as it enters the Caribbean.

As for 98L that system is a fish storm will remain out over the north Atlantic until a cold front sweeps it northeast.

GFS model from this morning may have gone bonkers suggesting a tropical cyclone development over the southern Caribbean and a track over Cuba and landfall over southern Florida.

Although this is a hot area during the latter half of September and October, I have to see a consistent model run by run showing the same scenario.  I will monitor that as well but for now it remains questionable...RTW

TROPICAL UPDATE SEPT 19, 2018... 1055 AM EDT

Invest 97L
Has a Low chance 20% within 48 hrs and within 5- days.  However, this system is going to encounter hostile conditions ahead as it tracks toward the west-northwest.  Dry air ahead of this system will more than likely inhibit development.  Model suggesting dissipation as it tracks over the islands or north of the islands.

I will be monitoring west of Africa below 10 deg latitude along the monsoonal trough which seems active with showers and storms.  This trough is far enough south and is not being influenced by Sahara Dry Air and Dust.  Models want to develop some lows along this trough.  However,although some make it to the east Caribbean they seem to dissipate over the Central Caribbean.  Still to far out in the future and this may never materialize.  I will keep you posted...RTW

TROPICAL WEATHER OUTLOOK SEPT 9, 2018... 0400 PM EDT

013 
AXNT20 KNHC 191745
TWDAT 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
145 PM EDT Wed Sep 19 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 
1715 UTC.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave is along 19W/20W from 20N 
southward, moving W at 10 kt. This wave is associated with a 
distinct 700 mb trough. Scattered showers over Africa from 14N- 
18N between 12W-17W. Widely scattered moderate convection is over 
the southern portion of the wave over the Atlantic from 05N-08N 
between 18W-25W.

A surface trough is over the the E Atlantic from 20N28W to 12N31W,
moving NW at 15 KT. This trough has no significant convection. It
is associated with a distinct 700 mb trough.  

A surface trough is over the Atlantic along 46W/47W from 12N 
southward, moving W at 10-15 kt. This trough may be developing a 
surface low. Isolated moderate convection is from 04N-14N between
40W-50W. 

A Caribbean tropical wave is along 64W/65W from 19N southward, 
moving W at 15 kt. Isolated moderate convection is from 10N-17N 
between 58W-64W.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes from W Africa near 13N16W, to 12N19W. 
The ITCZ continues from 10N21W to 08N30W to 07N45W. Scattered 
moderate convection is from 04N-10N between 25W-35W.

...DISCUSSION...

GULF OF MEXICO...

The northern extent of a surface trough, the remnants of Isaac, 
is over the Yucatan Peninsula. Scattered moderate convection is
over the Yucatan Channel and the eastern Yucatan Peninsula. Weak
surface ridging is over the remainder of the Gulf of Mexico with
axis along 28N.  

In the upper levels an upper level low is centered over S Texas
near 28N98W. Upper level diffluence is over the W Gulf. Scattered
showers are from 20N-25N between 95W-98W. The remainder of the
Gulf has mostly fair weather. 

The remnants of Isaac will move across the Yucatan Channel
today and move into the southwest Gulf of Mexico Thu and Fri.

CARIBBEAN SEA...

The remnant trough of Isaac extends from 22N86W to the Gulf of
Honduras near 16N88W. Widely scattered moderate convection is over
the NW Caribbean N of 15N between 79W-89W. 

Scattered moderate to isolated strong convection is over the SW 
Caribbean S of 15N between 77W-87W. The monsoon trough is along 
09N over Costa Rica and Panama enhancing convection. 

A tropical wave is over the E Caribbean. See above. This tropical 
wave will move west across the central Caribbean Thu into Fri, 
and pass west of the area through late Sat into Sun. Strong gusts 
are possible near showers and thunderstorms associated with this 
tropical wave near the Lesser Antilles and eastern Caribbean. 
Meanwhile high pressure building from the central Atlc into the 
central Bahamas will support moderate to fresh trade winds and 
building seas across the entire basin late Wed through Fri. 

ATLANTIC OCEAN...

A quasi-stationary front is off the coast of Georgia. Scattered
moderate convection is from 29N-31N between 74W-78W. A surface
trough is further E from 34N64W to 28N68W. Scattered showers are
within 90 nm of this trough. A 1022 mb high is centered over the
central Atlantic near 28N49W. The remnant low of Joyce is over the
E Atlantic near 30N29W. Scattered showers are within 120 nm of the
center. 

Of note in the upper levels, an upper level low is centered over
the W Atlantic near 31N66W enhancing convection. 

Low pressure moving off the Carolinas tonight will drag an 
attendant frontal trough across the NW Atlantic waters north of 
27N Thu and Fri. The low will sink to near 31N67W Fri evening then
drift W and slowly weaken Sat and Sun. NE swell will dominate 
waters N of 26N over the weekend. 

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

$$
Formosa

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ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Wed Sep 19 2018

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

1. Shower activity associated with a tropical wave located about 1000
miles east of the Windward Islands has decreased some this morning.
Further development is becoming less likely since the environment is
becoming unfavorable for tropical cyclone formation.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

2. A non-tropical low is forecast to form this weekend between Bermuda
and the Azores.  After that time, conditions are expected to be
favorable for subtropical or tropical cyclone formation while the
low meanders over the north Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...20 percent.

Forecaster Avila

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