Tropical Wave (Ex-Invest 96L) Near Hispanola

[wxman57]

I'm not so enthusiastic about development. Just like many early Cape Verde systems, it has a bit of a twist coming off Africa but most fall apart in a day or two. Have a feeling this one won't look like much in a couple of days.

What are your thoughts about the one ahead of it?

Even less of a chance for the one ahead of it. Looking at satellite this morning, 96L may already be "poofing". Will need to take a look at some visible sat pics when I get in to the office to confirm.

[Alyono]

the models show the one ahead of it trying to organize but running into Hispañiola.

This one, just dies due to very unfavorable environmental conditions

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT THU JUL 28 2016

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

A tropical wave accompanied by a low pressure system is producing an
area of showers and thunderstorms about 400 miles southeast of the
Cabo Verde Islands. Some development of this disturbance is
possible during the next few days while it moves westward or
west-northwestward at 10 to 15 mph. However, environmental
conditions are expected to become less conducive for development
early next week when the system is over the central tropical
Atlantic Ocean.
* Formation chance through 48 hours...low...30 percent
* Formation chance through 5 days...medium...40 percent

$$
Forecaster Stewart

[Gustywind]

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
746 PM EDT WED JUL 27 2016


A tropical wave in the far east Tropical Atlantic with axis that
extends from 15N18W to 07N19W, moving west 10 to 15 kt over the
past 12 hours. The wave coincides with a 700 mb trough south of
12N as depicted in the global models and is embedded within broad
area of abundant moisture as seen on the SSMI Total Precipitable
Water imagery. Scattered moderate convection is from 06N-10N
between 12W-21W.

[JaxGator]

 https://twitter.com/mjventrice/status/758591128686002176

So the Euro ensembles still develop 96L.

[wxman57]

Neither the Euro nor the GFS does much with 96L. Both have the wave just out ahead of it as a stronger system when it tracks across the islands of the northern Caribbean this weekend and early next week, though neither indicates much development, just a wave axis. Neither looks particularly impressive on visible imagery.

[Kazmit]

It's still at 30%/40%, I thought it would have increased by now... It's going to have to beat the next SAL outbreak before conditions deteriorate early next week. Maybe it could find somewhere near the Bahamas/Florida region to develop?

[tolakram]

1KM blurry visible from CIMSS



source: http://tropic.ssec.wisc.edu/#

[wxman57]

1KM blurry visible from CIMSS

http://i.imgur.com/vLqdTBm.gif

source: http://tropic.ssec.wisc.edu/#

The lat/lon grid on that satellite looks to be about 2 degrees off. On my two sources, I'm seeing the rotation and heaviest convection just a little west of 20W. On the loop above, it's around 22W-23W, well west of that "I" marking the disturbance location.

[wxman57]

It's still at 30%/40%, I thought it would have increased by now... It's going to have to beat the next SAL outbreak before conditions deteriorate early next week. Maybe it could find somewhere near the Bahamas/Florida region to develop?

The percentages won't go up unless there is greater model support for development and/or it begins to look better-organized on satellite.

[AdamFirst]

Yeah I'm not too optimistic about this system surviving - but I'll continue to keep watch.

[gatorcane]

Convection is on the increase on the western side...

http://rammb.cira.colostate.edu/ramsdis ... display=12

[JaxGator]

Maybe. They might mean the wave in front of 96L due to the latitude and longitude mentioned.

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1030 AM EDT THU 28 JULY 2016
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 29/1100Z TO 30/1100Z JULY 2016
TCPOD NUMBER.....16-063

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY: POSSIBLE LOW LEVEL INVEST
AT 30/1800Z NEAR 16.5N 57.5W WITH 6-HRLY FIXES TO FOLLOW
IF SYSTEM DEVELOPS.

[USTropics]

06z Ensemble % Prob of TC genesis:

[Hurricaneman]

Maybe. They might mean the wave in front of 96L due to the latitude and longitude mentioned.

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1030 AM EDT THU 28 JULY 2016
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 29/1100Z TO 30/1100Z JULY 2016
TCPOD NUMBER.....16-063

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY: POSSIBLE LOW LEVEL INVEST
AT 30/1800Z NEAR 16.5N 57.5W WITH 6-HRLY FIXES TO FOLLOW
IF SYSTEM DEVELOPS.

Thats for pouch6L

[Nimbus]

That answers that question..
Might be far enough south to avoid the worst of the SAL.
Nice to have an early call like this.

[USTropics]

New post by Jeff Masters about 96L





96L Off the Coast of Africa Growing More Organized
By: Jeff Masters , 2:01 PM GMT on July 28, 2016
https://www.wunderground.com/blog/JeffM ... -organized

A strong tropical wave that moved off the coast of Africa on Wednesday morning has become more organized over the far eastern Atlantic, and has the potential to develop into a tropical depression in the coming days as it tracks west-northwestward at 10 - 15 mph into the middle Atlantic. NHC designated this disturbance Invest 96L on Wednesday morning--the first "Invest" of the year for an African tropical wave. Satellite loops on Thursday morning showed 96L had a compact area of heavy thunderstorms, and this activity had acquired a modest degree of organization. Some spin was evident in the cloud pattern, and low-level spiral banding features had begun to appear. Wind shear was a light 5 - 10 knots, and sea surface temperatures (SSTs) were warm, near 28°C (82°F), which was about 1°C (1.8°F) above average. Water vapor satellite imagery showed that the eastern tropical Atlantic was quite moist, with the dry air of the Saharan Air Layer (SAL) several hundred miles north of 96L. These conditions are favorable for development of a tropical depression.


Figure 1. Analysis of the Saharan Air Layer (SAL) from 8 am EDT (12 UTC) Thursday, July 28, 2016, showed that the dry air and dust of the SAL lay a few hundred miles to the north of 96L. Image credit: University of Wisconsin CIMSS/NOAA Hurricane Research Division.

Forecast for 96L
Steering currents favor a west to west-northwesterly motion at 10 - 20 mph for 96L over the next five days, and the storm should reach a point near 40°W, midway between the Lesser Antilles Islands and Africa, on Sunday. The 8 am EDT Thursday run of the SHIPS model predicted modestly favorable conditions for development through Saturday morning, with wind shear in the light to moderate range, 5 - 15 knots, a moist atmosphere, and warm SSTs near 27.5 - 28°C (81 - 82°F.) However, on Saturday and Sunday, 96L will encounter cooler waters, with temperatures a marginal 26.5 - 27°C (80 - 81°F). The SHIPS model also predicts that wind shear over the weekend will become moderate to high, 15 - 25 knots, and the atmosphere will get very dry, due to an intrusion of the Saharan Air Layer (check out the 10-day African dust forecast from NASA.) These unfavorable conditions would stymie any development of 96L.

The Thursday morning operational runs of our three reliable models for predicting tropical cyclone genesis, the European, GFS and UKMET models, all supported some limited development of 96L, but stopped short of predicting it would become a tropical depression. The 00Z Thursday run of the GFS ensemble forecast, done by taking the operational high-resolution version of the model and running it at lower resolution with slight perturbations to the initial conditions in order to generate a range of possible outcomes, had more than 50% of its twenty ensemble members predict that a tropical depression would form this weekend or early next week in the eastern Atlantic. Most of these forecasts had the storm dying out the middle Atlantic, due to unfavorable conditions, and none had it becoming a hurricane. Between 10 - 20% of the 50 members of the 00Z Thursday European ensemble model forecasts showed 96L becoming a tropical depression. In their 8 am EDT Thursday Tropical Weather Outlook, NHC gave 96L 2-day and 5-day development odds of 30% and 40%, respectively. Though the long-range uncertainty on what 96L might do is high, one reasonable scenario is for the system to steadily grow in organization the next few days, come close to or achieve tropical depression status by Saturday, then get ripped up by wind shear and dry air well before reaching the Lesser Antilles Islands by the middle of next week. Should 96L become a tropical storm, the next name on the Atlantic list is Earl.

Eastern Pacific getting less active
For the first time since July 2, there is only one active tropical cyclone in the Eastern Pacific: Tropical Storm Frank, which peaked as a Category 1 storm on Tuesday. Frank is degenerating quickly over 23°C waters and is likely to dissipate by Thursday evening, potentially giving us on Friday our first tropical cyclone-free day in the Eastern Pacific since July 1. Beginning on July 2, the Eastern Pacific had Tropical Storm Agatha form, followed by Category 4 Hurricane Blas, Category 2 Hurricane Celia, Category 3 Hurricane Darby, Tropical Storm Estelle, Category 1 Hurricane Frank and Category 4 Hurricane Georgette. This puts us far ahead of climatology: the Eastern Pacific usually does not see its seventh named storm until August 7, its fifth hurricane until August 26, and its third major hurricane until September 20. An average season has 15 named storms, 8 hurricanes, and 3 major hurricanes. The quiet may not last long: in their 8 am EDT Thursday Tropical Weather Outlook, NHC gave a new tropical disturbance a few hundred miles south of the southern tip of Mexico's Baja Paninsula 2-day and 5-day development odds of 20% and 70%, respectively. This storm--which would be named Howard if it gets to tropical storm strength--is expected to move west-northwest and not impact Mexico.

Jeff Masters

[gatorcane]

looks like it is starting to try and detach from the monsoon trough / ITCZ looking at the latest VIS loops. Could be the beginning of some development / genesis though the latest GFS run is not really impressed:

http://rammb.cira.colostate.edu/ramsdis ... display=12

[TheStormExpert]

What I see happening with 96L is it detaches from the Monsoon Trough/ITCZ and starts struggling due to dry stable air and some SAL, then it fizzles out not too far west of where it is now in the Central Tropical Atlantic.

The wave in front of it(Pouch 06L) which should be designated Invest 97L within the next 24hrs. definitely bears watching! If Pouch 06L can go north of the Greater Antilles it definitely in my opinion could be a legit threat to develop.

[NDG]

I think 96L could be a threat down the road, in the medium range it may indeed weaken to an open TW due to SAL if it gains too much latitude but I do not believe how the GFS paints a very hostile environment of windshear near the Leeward Islands which they forecast for this system to get torn apart by strong UL winds.

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.