Invest 90L: East Atlantic-Discussions,Analysis,Sat Pics

[Aric Dunn]

although latest quikscat shows a closed circulation does not show very strong winds.
I imagine that there are stronger winds than that. it maybe because the pass missed most of the system.

[DrewFL]

Given the fact that the latest Scatt pass missed most of our EATL low. I can only imagine the NHC will just sit on it till 11:30 Sunday before thinking about a move.

[Normandy]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.



Evening Thoughts,
Im gonna have to give the GFS credit....it has scored BIG time with this and for all intents and purposes this appears to be close to a Tropical Depression right where the GFS progged it to become one. Very impressive.

Looking at the QScat I can identify a couple of 35kt barbs and more 30kt barbs, but those aren't enough to warrant naming this yet. Whats more impressive is the incredibly healthy circulation....Winds are well defined in all directions around the low pressure, and only get ragged towards the N side of the cyclone with not much in the way of due Easterly winds....Despite this small issue, in my humble opinion this is likely a legitimate tropical depression and if it were close to home it would be classified most likely. However I do agree with the NHC with their "wait and see attitude."

The track is worrisome for the islands, as the ridge is forecasted to be pretty decent...
http://www.nco.ncep.noaa.gov/pmb/nwprod ... 0_090l.gif
This shows the picture quite well, and it paints a pretty awful scenario for the northern leeward islands and Puerto Rico.

In addition to the track im concerned about the possible strength of this thing.

http://www.aoml.noaa.gov/phod/dataphod1 ... 7222at.jpg
http://www.aoml.noaa.gov/phod/dataphod1 ... 2atsst.png

Oceanic Heat Content and SST's along the path of this wave are marginal at best, and really won't be exceptionally conducive for any type of fast intensification of this system. Only when the system nears the islands will it really have the oppurtunity to become a potent storm. And even near the islands, the heat potential and SST's aren't blazing hot. This is good news and bad news: The good news is that, in my opinion, I doubt this strikes the islands (if it does) as anything higher than a strong Category 3. The bad news is that when the storm approaches the islands it might be in an intensification phase, and the HWRF shows this in its last run. I think people in the islands need to closely monitor this storm, as major hurricanes are very serious (and I do believe this has potential to become one).

One thing we can't be so sure about is shear down the road, and that can be a serious player in regards to future intensity. Still I am pretty confident this will threaten the Northern Islands and Puerto Rico. I don't feel it will get strong early, so I feel it will move basically westward to wnw for the next 4 days. That puts it in a dangerous position to strike the Northern Islands.

[Aric Dunn]

good analysis normandy

finally the NRL updates the sat image not very clear but maybe they can keep it up

[cycloneye]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.



Evening Thoughts,
Im gonna have to give the GFS credit....it has scored BIG time with this and for all intents and purposes this appears to be close to a Tropical Depression right where the GFS progged it to become one. Very impressive.

Looking at the QScat I can identify a couple of 35kt barbs and more 30kt barbs, but those aren't enough to warrant naming this yet. Whats more impressive is the incredibly healthy circulation....Winds are well defined in all directions around the low pressure, and only get ragged towards the N side of the cyclone with not much in the way of due Easterly winds....Despite this small issue, in my humble opinion this is likely a legitimate tropical depression and if it were close to home it would be classified most likely. However I do agree with the NHC with their "wait and see attitude."

The track is worrisome for the islands, as the ridge is forecasted to be pretty decent...
http://www.nco.ncep.noaa.gov/pmb/nwprod ... 0_090l.gif
This shows the picture quite well, and it paints a pretty awful scenario for the northern leeward islands and Puerto Rico.

In addition to the track im concerned about the possible strength of this thing.

http://www.aoml.noaa.gov/phod/dataphod1 ... 7222at.jpg
http://www.aoml.noaa.gov/phod/dataphod1 ... 2atsst.png

Oceanic Heat Content and SST's along the path of this wave are marginal at best, and really won't be exceptionally conducive for any type of fast intensification of this system. Only when the system nears the islands will it really have the oppurtunity to become a potent storm. And even near the islands, the heat potential and SST's aren't blazing hot. This is good news and bad news: The good news is that, in my opinion, I doubt this strikes the islands (if it does) as anything higher than a strong Category 3. The bad news is that when the storm approaches the islands it might be in an intensification phase, and the HWRF shows this in its last run. I think people in the islands need to closely monitor this storm, as major hurricanes are very serious (and I do believe this has potential to become one).

One thing we can't be so sure about is shear down the road, and that can be a serious player in regards to future intensity. Still I am pretty confident this will threaten the Northern Islands and Puerto Rico. I don't feel it will get strong early, so I feel it will move basically westward to wnw for the next 4 days. That puts it in a dangerous position to strike the Northern Islands.

I added our disclaimer at the top of your post.

[rjgator]

The winds are starting to shift from the N to NNW to NW at this bouy. It looks like it is pretty close to the system.

http://www.ndbc.noaa.gov/station_page.php?station=13001

[HurricaneMaster_PR]

WEATHER SUMMARY FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR

1021 PM AST SAT AUG 11 2007

PARTLY CLOUDY SKIES PREVAILED ACROSS THE EASTERN HALF OF PUERTO RICO
WHILE THE WESTERN SECTIONS WERE VARIABLY CLOUDY THIS EVENING.
CONSIDERABLE HAZE WAS ALSO NOTED AS SAHARAN DUST CONTINUES OVER THE
AREA. NWS DOPPLER RADAR SHOWED A LINE OF SHOWERS SHOWERS OVER THE
ATLANTIC COASTAL WATERS MOVING ALMOST PARALLEL TO THE COAST. WINDS
WERE FROM THE EAST AT AROUND 15 MPH.

AFTERNOON SHOWERS AND A POSSIBLE THUNDERSTORM CAN BE EXPECTED SUNDAY
ACROSS NORTHWEST AND INTERIOR PORTIONS OF PUERTO RICO...A RESULT OF
DAYTIME HEATING AND LOCAL WIND EFFECTS. OTHERWISE...ISOLATED SHOWERS
ARE EXPECTED.
DUE TO WINDS...MARINE CONDITIONS WILL REMAIN ROUGH AND CHOPPY ACROSS
THE OFF SHORE CARIBBEAN AND ATLANTIC WATERS THROUGH THE
WEEKEND...WHERE SMALL CRAFT SHOULD EXERCISE CAUTION.

A VIGOROUS TROPICAL WAVE HAS EMERGED OFF OF AFRICA IN THE PAST 30
HOURS...AND SEVERAL OF THE COMPUTER MODELS ARE INDICATING THAT
ATMOSPHERIC CONDITIONS MAY BECOME FAVORABLE FOR THIS WAVE TO BECOME
BETTER ORGANIZED AND INTENSIFY AS IT MOVES WESTWARD ACROSS THE
TROPICAL ATLANTIC. LOCAL INTERESTS ARE REMINDED THAT WE ARE ENTERING
THE PEAK MONTHS OF THE HURRICANE SEASON...AND ALL LOCAL INTERESTS
SHOULD REMAIN ALERT TO TROPICAL WEATHER DEVELOPMENTS.

[DrewFL]

WEATHER SUMMARY FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR

1021 PM AST SAT AUG 11 2007

PARTLY CLOUDY SKIES PREVAILED ACROSS THE EASTERN HALF OF PUERTO RICO
WHILE THE WESTERN SECTIONS WERE VARIABLY CLOUDY THIS EVENING.
CONSIDERABLE HAZE WAS ALSO NOTED AS SAHARAN DUST CONTINUES OVER THE
AREA. NWS DOPPLER RADAR SHOWED A LINE OF SHOWERS SHOWERS OVER THE
ATLANTIC COASTAL WATERS MOVING ALMOST PARALLEL TO THE COAST. WINDS
WERE FROM THE EAST AT AROUND 15 MPH.

AFTERNOON SHOWERS AND A POSSIBLE THUNDERSTORM CAN BE EXPECTED SUNDAY
ACROSS NORTHWEST AND INTERIOR PORTIONS OF PUERTO RICO...A RESULT OF
DAYTIME HEATING AND LOCAL WIND EFFECTS. OTHERWISE...ISOLATED SHOWERS
ARE EXPECTED.
DUE TO WINDS...MARINE CONDITIONS WILL REMAIN ROUGH AND CHOPPY ACROSS
THE OFF SHORE CARIBBEAN AND ATLANTIC WATERS THROUGH THE
WEEKEND...WHERE SMALL CRAFT SHOULD EXERCISE CAUTION.

A VIGOROUS TROPICAL WAVE HAS EMERGED OFF OF AFRICA IN THE PAST 30
HOURS...AND SEVERAL OF THE COMPUTER MODELS ARE INDICATING THAT
ATMOSPHERIC CONDITIONS MAY BECOME FAVORABLE FOR THIS WAVE TO BECOME
BETTER ORGANIZED AND INTENSIFY AS IT MOVES WESTWARD ACROSS THE
TROPICAL ATLANTIC. LOCAL INTERESTS ARE REMINDED THAT WE ARE ENTERING
THE PEAK MONTHS OF THE HURRICANE SEASON...AND ALL LOCAL INTERESTS
SHOULD REMAIN ALERT TO TROPICAL WEATHER DEVELOPMENTS.

So, How do you feel about that discussion?

[HurricaneMaster_PR]

WEATHER SUMMARY FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR

1021 PM AST SAT AUG 11 2007

PARTLY CLOUDY SKIES PREVAILED ACROSS THE EASTERN HALF OF PUERTO RICO
WHILE THE WESTERN SECTIONS WERE VARIABLY CLOUDY THIS EVENING.
CONSIDERABLE HAZE WAS ALSO NOTED AS SAHARAN DUST CONTINUES OVER THE
AREA. NWS DOPPLER RADAR SHOWED A LINE OF SHOWERS SHOWERS OVER THE
ATLANTIC COASTAL WATERS MOVING ALMOST PARALLEL TO THE COAST. WINDS
WERE FROM THE EAST AT AROUND 15 MPH.

AFTERNOON SHOWERS AND A POSSIBLE THUNDERSTORM CAN BE EXPECTED SUNDAY
ACROSS NORTHWEST AND INTERIOR PORTIONS OF PUERTO RICO...A RESULT OF
DAYTIME HEATING AND LOCAL WIND EFFECTS. OTHERWISE...ISOLATED SHOWERS
ARE EXPECTED.
DUE TO WINDS...MARINE CONDITIONS WILL REMAIN ROUGH AND CHOPPY ACROSS
THE OFF SHORE CARIBBEAN AND ATLANTIC WATERS THROUGH THE
WEEKEND...WHERE SMALL CRAFT SHOULD EXERCISE CAUTION.

A VIGOROUS TROPICAL WAVE HAS EMERGED OFF OF AFRICA IN THE PAST 30
HOURS...AND SEVERAL OF THE COMPUTER MODELS ARE INDICATING THAT
ATMOSPHERIC CONDITIONS MAY BECOME FAVORABLE FOR THIS WAVE TO BECOME
BETTER ORGANIZED AND INTENSIFY AS IT MOVES WESTWARD ACROSS THE
TROPICAL ATLANTIC. LOCAL INTERESTS ARE REMINDED THAT WE ARE ENTERING
THE PEAK MONTHS OF THE HURRICANE SEASON...AND ALL LOCAL INTERESTS
SHOULD REMAIN ALERT TO TROPICAL WEATHER DEVELOPMENTS.

So, How do you feel about that discussion?

Just posted it because there are a couple of members from Puerto Rico in this board, and I wanted to point out that the NWS in San Juan has been keeping close tabs on the system..I think people in the islands should keep monitoring the situation as there is a high possibility that a tropical cyclone could threaten us at the end of the week...

[jasons2k]

I wanted to wait this one out for a day or so and I must say I am impressed. It looks like it's showtime to me.

[hsvwx]

Hello all,

I'm more of a reader than a poster, but just thought I would comment about the possible recurvature of this POTENTIAL storm. Like everyone has said, the stronger a storm becomes, the more it is steered by the mid and upper level currents. However, we must also remember that typically, as a storm becomes stronger, it is displacing more mass in its outflow channels. Due to mass continuity, the air sinks in the region of the subtropical high, which acts to strengthen the subtropical high (in this case the Bermuda high). So while there could be a weakness in the high pressure, it may fill in or become weaker as a result of a strong storm, limiting potential recurvature effects. Of course if there is a strong trough weakening the ridge, that's a completely different story.

[DrewFL]

HurricaneMaster_PR .....Thanks for the reply. I, personally will be around if something should threaten your area.

[Aric Dunn]

Hello all,

I'm more of a reader than a poster, but just thought I would comment about the possible recurvature of this POTENTIAL storm. Like everyone has said, the stronger a storm becomes, the more it is steered by the mid and upper level currents. However, we must also remember that typically, as a storm becomes stronger, it is displacing more mass in its outflow channels. Due to mass continuity, the air sinks in the region of the subtropical high, which acts to strengthen the subtropical high (in this case the Bermuda high). So while there could be a weakness in the high pressure, it may fill in or become weaker as a result of a strong storm, limiting potential recurvature effects. Of course if there is a strong trough weakening the ridge, that's a completely different story.

that is true and good point but it all depends on the size of the storm .. large hurricanes can change there surrounding environment to a extent in the manner you mentioned but if this system remain small the amount that it could potentially strengthen the ridge. but that is something to note as well.

[Normandy]

^I think the strength (or lack thereof) of this storm in the short term increases the likelihood that this will enter the area of the Northern Leewards and PR. I really don't feel this is gaining much lattitude from its current position to 50 west....its just A) Not strong enough to nudge against the ridge to its north, and B)it probably won't get strong enough to budge the ridge in the near term. I am NOT sold on this going into the Carribean like the GFS runs are currently depicting, as that is too far out for any kind of certainty.

Another thing I want to speculate upon this sytem.....as you can see by the QSCAT the system, is, well HUGE. Especially for a wave that just exited the coast, and its possible that when this does develop it could be a pretty large hurricane with a big windfield. Again I am just very very impressed with the GFS, it should get major kudos.

[RL3AO]

Someone mentioned the buoy.



Winds have shifted from the N to NW, so it does show that there is some type of low level circulation.

[DrewFL]

hsvwx.....unpopular thought here. But not every system is destined to hit the GOM!
Let's see what happens to our Island friends first. OK?

[jasons2k]

aka "pumping the ridge"

[DrewFL]

aka "pumping the ridge" LOL!

[rjgator]

I am amazed at the continuity between all of the models with this thing. They have been predicting it and now have all caught on to it and the tracks are very similar for a storm in it infancy stages. It will be real interesting if they remain in such good agreement over the next couple of days. It seems like the GFS had this thing coming off for like a week now.

[vaffie]

Wow, impressive consistency for a 276 hour forecast! Between Brownsville and Houston. I've often noticed with these longtracking storms that the worst news is when the model predicts the storm will track south of you--because by hook or by crook there always ends up being some weakness in the high that you couldn't predict long in advance that ends up pulling it north by the end. So for me a model track showing Brownsville or south of there is more concerning than a track for Houston, because the storm will always have ample opportunity to nudge north over time.