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A very robust tropical wave is cross the Atlantic and should be INVEST 97L in the near future.
TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT THU JUL 28 2016

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

1. A tropical wave located about 1700 miles east-southeast of the
Leeward Islands is moving westward at about 30 mph. Environmental
conditions are expected to be somewhat conducive for development
this weekend when the disturbance could be near the northern Lesser
Antilles and Puerto Rico.
* Formation chance through 48 hours...low...20 percent
* Formation chance through 5 days...low...30 percent

2. A tropical wave accompanied by a low pressure system is producing an
area of showers and thunderstorms about 350 miles south-southeast of
Cabo Verde. 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


The GEFS Ensemble Members are beginning to raise an eyebrow regarding potential tropical development, particularly in the Western Caribbean Sea and that will need to be monitored very carefully as it could have effects on our sensible weather forecast later next week. Stay Tuned!

Update from Jeff:

As mentioned this morning the tropical wave west of 96L was starting to look more concentrated and the morning global model runs show a little more support for the development of this wave than previous runs. NHC has included a 30% development region over the next 5 days from this feature as it moves generally W to WNW toward the eastern Caribbean Islands. Overall global model trends may be a bit fast in the forward motion and it is still questionable on just how much development is likely with the feature.

The CMC model solution is the much more intense outlier compared to the ECMWF and GFS guidance.

This is a good time to remind everyone that you should have a hurricane plan developed and ready to be used. Things can happen very quickly this time of year.

CMC 983mb hurricane into NE MX, GFS has a 1009mb low heading for S TX, and the EURO shows an open wave into the WC Gulf. Something to watch, but not be alarmed about.

97L looks rather unimpressive this morning as it moves rapidly Westbound in a fast Easterly flow. It could bring showers and storms to the Antilles as it quickly moves along in a 30kt Easterly flow. No development is expected at this time with such a fast motion. IF the disturbance slows down later next week as it nears the Yucatan Peninsula and the Bay of Campeche, there is some potential, albeit low that tropical cyclone genesis could occur. Being a week away, we will monitor for any changes as the Tropical Wave gets closer to our backyard.
TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT FRI JUL 29 2016

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

1. A tropical wave located about 1200 miles east of the Lesser
Antilles is moving westward at about 25 mph. The associated shower
activity is poorly organized, and given the fast motion of the
system any development should be slow to occur. However, this system
will likely bring showers and gusty winds to portions of the Leeward
Islands and the eastern Caribbean Sea during the weekend.
* Formation chance through 48 hours...low...20 percent
* Formation chance through 5 days...low...30 percent

2. Shower activity associated with a tropical wave and a low pressure
system centered a couple of hundred miles south of the Cabo Verde
Islands has become better organized since yesterday. Some
additional development is possible during the next day or two before
the disturbance encounters a less favorable environment over the
central tropical Atlantic next week.
* Formation chance through 48 hours...medium...40 percent
* Formation chance through 5 days...medium...50 percent

Forecaster Beven

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT FRI JUL 29 2016

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

1. A tropical wave located about 1100 miles east of the Lesser
Antilles is moving westward at 20-25 mph. The associated shower
activity is poorly organized, and given the fast motion of the
system any development should be slow to occur. Regardless of
development, this system will likely bring showers and gusty winds
to portions of the Leeward Islands, Virgin Islands, Puerto Rico, and
the eastern Caribbean Sea during the weekend. By the middle of next
week, the wave is expected to be in the western Caribbean Sea, where
conditions could be more conducive for development.
* Formation chance through 48 hours...low...10 percent
* Formation chance through 5 days...low...30 percent

The 12Z ECMWF suggests 97L will begin to organize as it crosses the Yucatan Peninsula and possibly develop into a tropical cyclone as it nears S Texas.

Interestingly the 12Z ECMWF Ensembles are latching on to the idea that 97L may find more hospitable conditions in the NW Caribbean Sea and the Western Gulf of Mexico as the disturbance arrives next Thursday into Friday.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT FRI JUL 29 2016

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

1. A tropical wave located about 1000 miles east of the Lesser Antilles
is moving westward at 20-25 mph. Associated shower activity is
poorly organized, and given the fast motion of the system any
development should be slow to occur. Regardless of development,
this system will likely bring showers and gusty winds to portions of
the Leeward Islands, Virgin Islands, Puerto Rico, and the eastern
Caribbean Sea during the weekend. By the middle of next week, the
wave is expected to be in the western Caribbean Sea, where
conditions could become more conducive for development.
* Formation chance through 48 hours...low...10 percent
* Formation chance through 5 days...low...30 percent

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SAT JUL 30 2016

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

1. A tropical wave located about 700 miles east of the Lesser Antilles
is moving westward at 25 to 30 mph. While the associated shower
activity has increased since yesterday, any additional development
should be slow to occur due to the rapid motion of the system.
Regardless of development, this system will likely bring showers and
gusty winds to portions of the Leeward Islands, Virgin Islands,
Puerto Rico, and the eastern Caribbean Sea beginning later today.
By the middle of next week, the disturbance is expected to be in the
western Caribbean Sea, where conditions could become more conducive
for development.
* Formation chance through 48 hours...low...20 percent
* Formation chance through 5 days...medium...40 percent

From NWS Houston/Galveston this morning via Twitter:
NWSHouston ‏@NWSHouston · 51m51 minutes ago
7AM Tropical outlook from @NHC_Atlantic tracking 2 tropical waves. Here what it means for SE TX. #houwx #txwx

12Z Track and Intensity guidance for 97L.

how far from Gom 5-7 days?

ticka1 wrote:how far from Gom 5-7 days?

It could be nearing the NW Caribbean/Yucatan Peninsula next Friday at the fast forward motion it is currently traveling.

The Day 8+ Super Ensemble suggest the Upper Ridge will be anchored near the Upper/Mid Mississippi Valley Region in about 8 Days. Use this with caution as it only provides a possible glimpse into the future regarding the Upper Air Pattern. Also note that until an actual low level circulation organizes...if it does...the track and intensity guidance will change every 6 hours as more data becomes available.

srainhoutx wrote:The Day 8+ Super Ensemble suggest the Upper Ridge will be anchored near the Upper/Mid Mississippi Valley Region in about 8 Days. Use this with caution as it only provides a possible glimpse into the future regarding the Upper Air Pattern. Also note that until an actual low level circulation organizes...if it does...the track and intensity guidance will change every 6 hours as more data becomes available.

I agree totally the pattern the models are showing in 8 days may be very different from what the conditions may actually be..How many times have we saw that.

Saturday afternoon briefing from Jeff:

Main focus over the upcoming forecast cycle will be eventual track and intensity of Atlantic tropical wave 97L and its potential movement into the Gulf of Mexico late next week.

Near term forecast will be dominated by general high pressure building aloft over the state and gradually filling the weakness that has been over the region for the last week. Increasing heights aloft will result in warming afternoon temperatures and lessened chances for afternoon thunderstorms. 594dm ridge axis is near the region on Monday and Tuesday and this will be the hottest days with least rain chances with highs likely back into the mid to upper 90’s.

Ridge begins to weaken and shift northward Thursday and Friday which becomes critical in the eventual track of 97L as it enters the Gulf of Mexico. Models want to develop another weakness or “break” in the sub-tropical ridge axis over the NW Gulf coastal areas by next Friday which will at least result in lower afternoon high temperatures and better rain chances along the seabreeze. Main question quickly becomes how does this impact the final track outcome of tropical wave 97L and in what kind of shape will this feature be when it arrives in the Gulf of Mexico. For now any potential impact would be beyond the 5-6 day period, and given the recent model flip-flopping on the system there is little confidence in any one solution.

Now is the time to review your hurricane preparations and make sure you can enact those plans. Make it a point to check the weather at least once a day for the next week to keep update on changes with the tropics!

97L:
Strong tropical wave located 550 miles E of the Leeward Islands continues to race westward at 25-35mph. While showers and thunderstorms have increased in association with this feature this morning and banding features are looking more impressive, there is no evidence of a defined low level circulation from either surface observations of satellite overpasses. 97L is trapped within the strong trade wind flow south of a well defined sub-tropical ridge over the central Atlantic basin and this will bring the system rapidly into and across the Islands tonight and on Sunday and then into the eastern Caribbean Sea on Monday. The fast forward motion should preclude much development in the near term, but as the system reaches the central and western Caribbean Sea and begins to slow down conditions look increasingly favorable for formation of a tropical cyclone. Upper level winds appear favorable, sea surface temperatures are more than warm enough, and dry air should be mitigated. Experience with incoming strong waves into the eastern Caribbean Sea without well developed inner cores usually indicates the system will not develop until it reaches the western Caribbean Sea.

Beyond 4-5 days global models bring 97L as a developed tropical cyclone into the southern Gulf of Mexico with various track and intensity solutions possible. Uncertainty is fairly large at this time range and the global model solutions have been showing large swings from run to run leading to lower than average confidence which is already low. Additionally, without a defined low level center for guidance to ingest into their vortex tracking there really is not much faith in any output at this time.

Analog years strongly support in close development of tropical cyclones this season and 97L deserves close watch once over the western Caribbean Sea and southern Gulf of Mexico late next week.

National Hurricane Center probability of tropical cyclone formation over the next 5 days with 97L is now 60%.

Rather unfavorable conditions ahead. 30-40kt shear ahead over the central/eastern Caribbean is going to really delay any formation until near the Yucatan Peninsula. Even then, low level steering suggests a near westward flow for much of the gulf. Going to be hard to gain much latitude until it strengthens some. GFS and ECMWF are on the southern track while some of the other models like the GFDL suggests it might shoot the gap (mainly because it remains stronger). Still plenty of time to figure things out.

00Z Track and Intensity guidance.

18Z GEFS Individual Ensemble members are suggesting anywhere from Veracruz to Vermilion Bay may need to keep a keen eye on future developments regarding 97L. A conducive Convectively Coupled Kelvin Wave arrives in the Western Caribbean Monday into Tuesday and could be the 'spark' that ignites much more favorable conditions and could allow for tropical cyclone genesis to happen. Stay tuned folks.!