ATL: Ex COLIN - Discussion

[Vortex]

NHC experimental product clearly indicates a different tune with the digestion of todays guidance than 24 hours ago. Keeps system well E of Bahamas compared to the same experimental model that looked to ravage the bahamas just 24 hours ago...

I'm not ready to abandon ship just yet too "Gone Fishing" but if tonights 00z runs continue to indicate a turn into the weakness and the Euro jumps even slightly on board than IMO I think most including the islands are in good shape....

***00Z runs EXTREMELY important tonight


NHC Experimental product Loop

http://www.nhc.noaa.gov/tafb/gridded_ma ... d#contents

[wzrgirl1]

very nice trend....at least we would have a nice storm to track with no land getting affected

[Ivanhater]

That experimental product is off the GFS, that is why it changed.

[TexasF6]

Just my opinion here, but until there is a LLC? And the EURO says_______, and recon gets in there, I don't trust the models this early....

[ronjon]

Actually I don't think the 00Z runs are that important - more like the model trends in the 500 mb pattern and the speed of 91L over the next few days. There's no certainty one week out. The pattern could flip back to stronger ridging as I seen too many times to count in these circumstances. Patience grasshopper.

[Vortex]

Exerpt from NWS San Juan this afternoon:
The part about the sub tropical ridge building in from the east and holding until the end of the week would be very significant and exactly what the Euro has been driving home. 00z NAM is rolling in and should be interesting to see how the supposed ULL is handled.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
334 PM AST SUN AUG 1 2010

.SYNOPSIS...SUBEQUATORIAL RIDGE WILL CONTINUE TO BUILD INTO THE
REGION FROM THE EAST AND HOLD THROUGH THE END OF THE WEEK.
TROPICAL WAVE JUST EAST OF THE LESSER ANTILLES WILL MOVE ACROSS
THE CARIBBEAN WATERS TUE. LARGE LOW PRES AREA MIDWAY BETWEEN
AFRICAN AND THE ANTILLES WILL LIKELY BECOME THE FOURTH TROPICAL
DEPRESSION OF THE 2010 ATLC HURRICANE SEASON AND MAY IMPACT THE
ISLANDS OF THE NORTHEAST CARIBBEAN TOWARD THE END OF THE WORK
WEEK.

[Chigger_Lopez]

I remember IKE last year and how the models were in a split camp and Derek and Wxman were very confident that it was heading out to sea in a weakness. I felt good about that, and like a day and a half later the cone had it coming right thru Ft. Lauderdale for an update and the news went nuts that morning. And we all know where IKE ended up making landfall. I think Wxmans prediction today of where it is going is spot on! Could be anywhere, although the trend is our friend

[Vortex]

HPC at day 7 issued today at 1800Z places soon to be Colin in the south central bahamas appraching Andros island. Per charts ridging appears well entrenched over the NE and SW atlantic. Interesting given the 12Z data they had time to digest...


http://www.hpc.ncep.noaa.gov/medr/nav_c ... fcolor=wbg

[TwisterFanatic]

HPC at day 7 issued today at 1800Z places soon to be Colin in the south central bahamas appraching Andros island. Per charts ridging appears well entrenched over the NE and SW atlantic. Interesting given the 12Z data they had time to digest...


http://www.hpc.ncep.noaa.gov/medr/nav_c ... fcolor=wbg

I agree, that is very interesting...

[cycloneye]

An anticyclone is building over 91L.

[spedras]

There is still a 10% chance the really big storm will never form. Let's cross our fingers!

[jcoffee]

A super strong ridge could steer it right into Florida.

[blazess556]

the storms so far this year have all tracked to west of the forecast tracks. the ridges strengths have been underforecasted.

[Dean4Storms]

HPC at day 7 issued today at 1800Z places soon to be Colin in the south central bahamas appraching Andros island. Per charts ridging appears well entrenched over the NE and SW atlantic. Interesting given the 12Z data they had time to digest...


http://www.hpc.ncep.noaa.gov/medr/nav_c ... fcolor=wbg

Well, they have it fairly weak so it looks like they rode the Euro for that one!

[MiamiHurricanes10]

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.

My view on things:

Satellite imagery continues to show that 91L is becoming increasingly organized and is well on its way to becoming a tropical depression. As noted on satellite imagery, 91L has begun to ignite organized deep flares of convection over its surface circulation. Convection is key for cyclogenesis as latent heat released by it warms the upper troposphere, this allows for a warm core to develop. As this warm core develops divergence aloft develops, which in turn causes for surface pressures to drop. Divergence aloft associated with 91L is very good thus the reason that several ships in the vicinity of 91L are reporting pressures of 1006mb. Earlier today as noted on total precipitable water there was some dry air entrainment associated with 91L in the northwestern quadrant, this now has been replaced by a much more moist environment. 91L is also accompanied by an anticyclone aloft as noted on CIMSS shear product. This anticyclone will lessen shear around 91L which currently stands at 5-15 knots. This anticyclone will also improve 91L's outflow channels. GFS shear forecasts suggest that this anticyclone move in tandem with 91L. However, 91L does have to work on some things before being classified as a tropical depression. An ASCAT pass from earlier this evening suggests that 91L's circulation is still a bit broad and not too well-defined. CIMSS vorticity product also suggests that 91L isn't vertically through the 850mb-500mb levels. With the favorable conditions that do surround 91L, I think, it shouldn't take long for this problems to be fixed. With all the parameters viewed by me I think there is a high chance that 91L will become a tropical depression in the next 48 hours. I also think there is a high chance that 91L will become tropical storm Colin in those 48 hours.

[canes04]

I'm watching the area near11.5n 37w for the LLC.
TD at anytime and Colin at 11am tomorrow.

I see that high buidling over it and moving in tandem.
I have seen the model trends today, but my Island friends don't let you guard down.

This could be a major heading your way within 5 days.
Good luck and lets hope for a recurve.

[Air Force Met]

I'm watching the area near11.5n 37w for the LLC.
TD at anytime and Colin at 11am tomorrow.

I see that high buidling over it and moving in tandem.
I have seen the model trends today, but my Island friends don't let you guard down.

This could be a major heading your way within 5 days.
Good luck and lets hope for a recurve.

It is HIGHLY doubtful that the NHC will upgrade this system to a TD before they have a good visible loop. That means it will be the 11 EDT advisory (most likely) before they upgrade it to a TD....short of a ship report of 25 kts of west wind and a 1005 mb pressure (for instance). It is possible they could upgrade at 5 am...but...to be honest...it really depends on who is working the night shift. If it's Avila...you can bet it won't be upgraded to a TD until 11 AM.

Remember...the NHC does not like to upgrade systems during the overnight hours when they are no threat to land (i.e. in the middle of the ocean). They like to wait until they have solid evidence of an LLC...which can usually be seen with VIS imagery. What you see on IR isn't always the whole truth of the matter.

[Vortex]

TUTT clearly defined on WV this evening NNE of PR....It's expected to remain there much of the week...

[gatorcane]

I'm watching the area near11.5n 37w for the LLC.
TD at anytime and Colin at 11am tomorrow.

I see that high buidling over it and moving in tandem.
I have seen the model trends today, but my Island friends don't let you guard down.

This could be a major heading your way within 5 days.
Good luck and lets hope for a recurve.

It is HIGHLY doubtful that the NHC will upgrade this system to a TD before they have a good visible loop. That means it will be the 11 EDT advisory (most likely) before they upgrade it to a TD....short of a ship report of 25 kts of west wind and a 1005 mb pressure (for instance). It is possible they could upgrade at 5 am...but...to be honest...it really depends on who is working the night shift. If it's Avila...you can bet it won't be upgraded to a TD until 11 AM.

Remember...the NHC does not like to upgrade systems during the overnight hours when they are no threat to land (i.e. in the middle of the ocean). They like to wait until they have solid evidence of an LLC...which can usually be seen with VIS imagery. What you see on IR isn't always the whole truth of the matter.

The posts in this forum are NOT official forecast 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.org. For official information, please refer to the NHC and NWS products

.

Makes little sense to me. As far as I am concerned this has been a depression since about noon today. If this were closer to the US mainland or Caribbean islands, I would bet this would already be a depression.

Looks like it continues to deepen and gain lattitude. Should be heading WNW then gradually it will bend to the NW over the next 4-5 days missing the islands to the NE. Reminds me alot if Bill from last year. Bill ended up about 800 miles east of Florida.

As I noted a few days ago, don't let the low lattitude fool you, many of storms have started there and moved east of the islands by a comfortable margin.

Sometimes I wonder, what if the Leewards were located farther NE. It almost seems like where they are located right now, they usually miss most systems as they pass to the east.

[Air Force Met]

Makes little sense to me. As far as I am concerned this has been a depression since about noon today. If this were closer to the US mainland or Caribbean islands, I would bet this would already be a depression.

Doesn't have to make sense to you...but those are the facts.

But...to be fair...if it were closer to the mainland...it would be a LOT easier to say it was a TD. You would have recon and a lot more obs available (shifts, buoys, etc). So...