ATL: Ex COLIN - Discussion

[ROCK]

It does not look too bad, but given it was at 30kts earilier today I don't think it looks any better since then, certainly not to upgrade anyway.

I disagree.. .cloud tops have warmed....no more of the cold tops from yesterday....its sitting over some very warm water over slight shear....LLC not fully tapping into the surface, IMO....still weak...

[Vortmax1]

The 18Z extrapolated forward motion is mostly NW.
I realize that is suspect but it has had a run to shake out of the initial reposition so is pretty accurate right now:


https://my.sfwmd.gov/portal/page/portal ... tab2200108

[ROCK]

Would have been better off staying in the ITCZ...without that energy, its really become weak on its own. SAL to the north, dry air and its forward motion are against it also....next up a nice big TUTT for dinner tomorrow...

I really think the test in the models will be in the short term...if this hits the NE Islands or skims them, the models overestimated the weakness (or the storms was weaker) in the short term.

Still looks mostly west so far...

west today is a good bet or wnw......I am probably way off in saying this but I think northern carib entry is not out of the question. Now that goes against all guidance but as you all know I am somewhat of a rogue, loner type anyway.....

[ROCK]

The 18Z extrapolated forward motion is mostly NW.
I realize that is suspect but it has had a run to shake out of the initial reposition so is pretty accurate right now:


https://my.sfwmd.gov/portal/page/portal ... tab2200108

It aint going anywhere but west entrenched in the easterly like this.....look at the steering layers.....

http://cimss.ssec.wisc.edu/tropic/real- ... 8dlm1.html

[sunnyday]

It never ceases to amaze me how much change in the predicted path of a storm changes within a couple of days. A couple of days ago, this wave was headed to S Fla, then it was going east as a fish, and now it is going north. I don't see the point in predictions so far out. Can someone explain why models are made that are almost certain to change very quickly?

[bvigal]

This very interesting!

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
347 PM AST MON AUG 2 2010

.SYNOPSIS...TUTT LOW NNE OF PR WILL MEANDER OVR THE NEXT COUPLE OF DAYS WHILE WEAKENING. MEANWHILE... SUBEQUATORIAL RIDGE IS EXPECTED TO BUILD FROM THE EAST WED AND HOLD THROUGH THE END OF THE WEEK. AT LOW LEVELS...TROPICAL WAVE ALONG 60W WILL MOVE ACROSS THE AREA TUE. TD#4 EXPECTED TO PASS NE OF THE AREA EARLY THU.
&&
....
TD#4 CONTINUES TO MOVE VERY RAPIDLY THIS AFTERNOON. ASSUMING TD#4 REMAINS A CLOSED VERTICALLY STACKED CIRCULATION IT SHOULD PASS TO THE NORTHEAST OF PR EARLY THU MORNING. HOWEVER...SYSTEM IS SMALL AND WILL BE ENCOUNTERING VERY DRY MID LEVEL AIR PER WATER VAPOR IMAGERY. GIVEN ITS FAST MOTION IT COULD ALSO STRUGGLE TO MAINTAIN A CLOSED CIRCULATION AND SVRL RELIABLE MODELS ARE SUGGESTING TD#4 WILL BECOME AN OPEN WAVE. IN THAT CASE...IT WOULD BE STEERED BY THE LOW LEVEL FLOW AND LIKELY TRACK MUCH CLOSER TO THE AREA. GIVEN THE FAST MOTION OF THE SYSTEM...HAVE SPED UP ASSOCIATED WX BRINGING SCT SHRAS TO COASTAL WATERS WED NIGHT AND THU. IT APPEARS THU WILL SEE VERY LIGHT WIND FLOW AND THIS COULD SET THE STAGE FOR A STRONG SEA BREEZE COLLISION OVR THE INTERIOR. SO STRONG CONVECTION WITH POTENTIALLY HEAVY RAINS A GOOD BET. SFC WIND FLOW TURNS SRLY FRI WITH TAIL END OF TD#4 LIKELY TO BRING ADDITIONAL MOISTURE. SO FCST DEFINITELY NOT A CLEAR CUT AND USERS ARE REMINDED THAT TRACK FCSTS ERRORS HAVE AVERAGED MORE THAN 200NM AT DAY4.

[Vortmax1]

look at the steering layers

Yes I have looked at them. So My thought is that will likely change to a more NWerly direction at the next run also. It's way too soon to know tracking for sure which is why I said it is suspect.

[Ivanhater]

[Gustywind]

[ronjon]

Looks to be moving almost due west now and will be south of the NHC 03/00Z forecast point in a few hours.

http://www.ssd.noaa.gov/goes/flt/t1/loop-vis.html

[Gustywind]

[KWT]

It does not look too bad, but given it was at 30kts earilier today I don't think it looks any better since then, certainly not to upgrade anyway.

I disagree.. .cloud tops have warmed....no more of the cold tops from yesterday....its sitting over some very warm water over slight shear....LLC not fully tapping into the surface, IMO....still weak...

Convection blowing up quite nicely right now over the center FWIW...

Still racing towards the dry air, going to be most interesting to see if TD4 can keep itself going in what looks like an increasingly poor set-up aloft.

[Vortmax1]

72 hour TPC surface fforecast...issued @ 18:37Z:

[cycloneye]

If it mantains the present motion,I can't see it avoiding the northern Leewards.On the other hand, PR doesn't need more big rainfall events as we are over 23 inches above normal for 2010.

[JTD]

Looks to be moving almost due west now and will be south of the NHC 03/00Z forecast point in a few hours.

http://www.ssd.noaa.gov/goes/flt/t1/loop-vis.html

Important to keep in mind that these things even out with time and just because it's south now doesn't mean it'll stay that way. It may miss it's forecast point to the north this time tommorow given the inherent unpredictability of wobbles.

On another note, TD #4 is looking very impressive on satelite images right now.

[cwachal]

convection is increasing right now... I think we will see a significant convection burst overnight tonight

[Gustywind]

If it mantains the present motion,I can't see it avoiding the northern Leewards.On the other hand, PR doesn't need more big rainfall events as we are over 23 inches above normal for 2010.

Yeah you're 100% right and Guadeloupe too have been well showered last month!

[KWT]

I just can't see it ending up getting quite that far north as the NHC expect but we will see...I suppose at least the first forecast point from the NHC won't be far off, the track still looks about 280 degrees right now.

[cwachal]

I expect that in 30 minutes we will see a shift westward and the northern islands will be in the southern portion of the track

[brunota2003]

Personal Forecast Disclaimer:
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.

I know this is more of a "throw the dart", but right now, I think TD #4 will go between Bermuda and Florida (no way, really?). I do not see it fully recurving, and I think the SE is at a pretty big risk of being impacted, with SC the highest risk imo. The models always screw up on the ridges and troughs this far out, and it will go somewhere between where the models say, it is all a matter of timing. I personally think 4 will get into the western Atlantic, a trough will pick it up, then it'll get shoved westward by a building ridge. Before it can make landfall (probably in northern FL/Georgia), a weakness will pick it up. Where it starts heading NW/N toward the weakness is going to determine whether it hits in northern GA, SC, or Southeastern NC. We can hope that it just goes away and out to sea, with minimum impact on anyone, but I just do not see it completing a recurve.