ATL: RAFAEL - Post-Tropical - Discussion

[cycloneye]

98L now has the SSD Floater.

http://www.ssd.noaa.gov/PS/TROP/floater ... oater.html

[cycloneye]

Joe Bastardi sends this twitter.

Joe Bastardi @BigJoeBastardi 55m
10N 45 west system likely to be a classified cyclone by the time it reaches Puerto Rico on weekend, Major rains at least with it for them

[cycloneye]

2 PM TWO:

A TROPICAL WAVE LOCATED ABOUT 900 MILES EAST OF THE WINDWARD ISLANDS
IS PRODUCING A LARGE AREA OF DISORGANIZED SHOWERS AND
THUNDERSTORMS. ANY DEVELOPMENT OF THIS SYSTEM DURING THE NEXT
COUPLE OF DAYS SHOULD BE SLOW TO OCCUR DUE TO MARGINALLY FAVORABLE
ENVIRONMENTAL CONDITIONS. THIS SYSTEM HAS A LOW CHANCE...20
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS
AS IT MOVES WEST-NORTHWESTWARD AT 15 TO 20 MPH.

[OURAGAN]

Dissipation is forecasted, read:

.ATLC 1008 MB LOW PRES 09N45W WITH TROPICAL WAVE FROM LOW TO
18N45W. FROM 10N TO 17N FROM 41W TO 53W NE TO E WINDS 20 TO 25
KT. SEAS 8 TO 10 FT.
.24 HOUR FORECAST 1010 MB LOW PRES NEAR 11N54W WITH TROPICAL
WAVE FROM LOW TO 18N53W. FROM 11N TO 17N BETWEEN 45W AND 54W NE
TO E WINDS 20 TO 25 KT. SEAS 8 TO 10 FT.
.48 HOUR FORECAST LOW PRES DISSIPATED. TROPICAL WAVE S OF 17N
ALONG 55W. FROM 12N TO 17N BETWEEN 47W AND 58W E WINDS 20 TO 25
KT. SEAS TO 9 FT.

.REMAINDER OF AREA WINDS 20 KT OR LESS. SEAS LESS THAN 8 FT.

$$
.FORECASTER DGS. NATIONAL HURRICANE CENTER.

[/img]

[Blown Away]

Joe Bastardi tweeting possible action for PR.

[cycloneye]

18z Best Track.

AL, 98, 2012100918, , BEST, 0, 93N, 483W, 25, 1008, LO

http://ftp.nhc.noaa.gov/atcf/tcweb/inve ... 012.invest

[gatorcane]

Convection on the increase and I see some broad cyclonic turning but the shear continues from the SW and it's very poorly organized. It doesn't quite have "that look" though but maybe that will change in the next 24-48 hours. Development looks possible but it will be a slow process. Model support is there for this and if I were in the northern Leewards/Puerto Rico area, something to keep an eye on.

[chaser1]

Dissipation is forecasted, read:

.ATLC 1008 MB LOW PRES 09N45W WITH TROPICAL WAVE FROM LOW TO
18N45W. FROM 10N TO 17N FROM 41W TO 53W NE TO E WINDS 20 TO 25
KT. SEAS 8 TO 10 FT.
.24 HOUR FORECAST 1010 MB LOW PRES NEAR 11N54W WITH TROPICAL
WAVE FROM LOW TO 18N53W. FROM 11N TO 17N BETWEEN 45W AND 54W NE
TO E WINDS 20 TO 25 KT. SEAS 8 TO 10 FT.
.48 HOUR FORECAST LOW PRES DISSIPATED. TROPICAL WAVE S OF 17N
ALONG 55W. FROM 12N TO 17N BETWEEN 47W AND 58W E WINDS 20 TO 25
KT. SEAS TO 9 FT.

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 appologize for the times that I simply do not remember to insert the disclaimer above, but wanted to make sure I did here. OH BOY, I think 98L could get interesting and here is why. In contrast to the forecast for the low latitude low to fill and disipate, I have real concerns that the CMC is on to something ("say it ain't so...". The logical reason for dissipation would occur from upper level conditions to worsen. I do not see conditions improving during the next 48 hours, however I am not sure I buy into them worsening either. Assuming that statement, the present TUTT feature that extends SW just ahead of 98L then NE over the E. Caribb and ENE from there, is forecasted by today's 12Z GFS 200mb maps, to look a bit different in 72 hours. In fact, at such time the present ridging over and just east of 97L appears to get shunted eastward and at such a time upper level conditions not only would appear to NOT be unfavorable ( perhaps a moderate southerly upper level flow IF void of 98L's own upper level anticyclone) but - and here's that word again "Assuming" the present upper level anticyclone continues to move along with the system, then things could get a bit nasty in the unlikely E. Caribbean.

When I look at the cut-off low over S. California, that energy seems to get pulled up and into the departing 200 mb trough which is at its deepest point down to the C. Conus Gulf Coast at about 36 hrs. Significant 200mb height rises are forecast to occur over N. Central Mexico thereafter. As this large feature fills in and builds in the wake of the eastward moving 200mb trough (which eventually lifts out), than it would appear that the present upper level high just east of the Bahamas and a bit east of 97L, become further pushed eastward thus causing a building & bridging ridge to occur over and/or just N. of Puerto Rico. This would likely simply pinch off the tail end of the present TUTT just north of Puerto Rico and likely send it westward. All the while a potentially developing depression/storm begins to organize somewhere in the S.E. or N.E. Caribb. If it were to simply be able to maintain itself, than I am not so sure that a low latitude system under 72hr-96hr steering might even go further westward than any reliable models presently see.

So for now, here is the big key that might ultimately dictate if Puerto Rico (or maybe Dominican Republic/Haiti) receives a significant impact from 98L. If the present convective trends continue despite present shear, than I would see little reason why its own developing upper high would not migrate westward along with the overall envelope/system. Should increased shear occur to the extent that convection dramatically diminishes (or becomes east/west stretched out, than sure - at minimum sooner development would be mitigated. In that case, I could still see development, but the process and timing would likely not allow the same extent of opportunity for a significant "wind event". Until I see 98L hit that perverbial wall, than this decent sized envelope system could spell problems for the Greater Antilles. "Just my 3 cents worth"......

[Sanibel]

Starting to look slightly better. This might have a chance.

[wxman57]

No development within 48 hrs, possible development beyond then - but I'm quite skeptical that the conditions in the eastern Caribbean which have been so hostile all year have improved. I measure the wave axis at about 775 miles east of the Lesser Antilles. Squalls should begin impacting the southern Antilles in just over 24 hrs. I don't buy the latest GFS at all. No way this will take until Sunday to move into the East Caribbean. More like early Thursday as per the Euro/Canadian and UKMET.

[Gustywind]

09/1800 UTC 8.5N 48.6W TOO WEAK 98L
09/1145 UTC 8.9N 42.1W TOO WEAK 98L

[wxman57]

09/1800 UTC 8.5N 48.6W TOO WEAK 98L
09/1145 UTC 8.9N 42.1W TOO WEAK 98L

It was way west of 42.1W at 1145Z today, closer to 45-46W. Not a good center to pick for Dvorak (8.9N/42.1W).

[storm4u]

http://tropics.hamweather.com/2012/atla ... est98.html

Location: Central Atlantic Lat: 9.3N Lon: 48.3W Moving: W 29 mph (25 kts) Pressure: 29.77 in (1008 mb)

[MGC]

Good bit of shear out ahead of the disturbance courtesy of a ULL to 98L NW....don't see anything forming the next couple of days until the ULL moves or fades away.....MGC

The above is the opinion of MGC and not an official forecast.

[cycloneye]

Remains at 20% on 8 PM TWO.

SHOWER AND THUNDERSTORM ACTIVITY ASSOCIATED WITH A TROPICAL WAVE
LOCATED ABOUT 850 MILES EAST OF THE WINDWARD ISLANDS HAS BECOME
MORE CONCENTRATED DURING THE LAST 24 HOURS. HOWEVER...ANY
DEVELOPMENT OF THIS SYSTEM SHOULD BE SLOW TO OCCUR DURING THE NEXT
COUPLE OF DAYS DUE TO STRONG UPPER-LEVEL WESTERLY WINDS. THIS
SYSTEM HAS A LOW CHANCE...20 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WEST-NORTHWESTWARD AT
15 TO 20 MPH.

[cycloneye]

SSD Dvorak up from TOO WEAK to T1.0.

09/2345 UTC 9.5N 50.2W T1.0/1.0 98L -- Atlantic

[Gustywind]

SSD Dvorak up from TOO WEAK to T1.0.

09/2345 UTC 9.5N 50.2W T1.0/1.0 98L -- Atlantic

Right, 98L numbers on the increase... and gaining a bit latitud.

[Gustywind]

Stu Ostro, Senior Meteorologist, The Weather Channel

http://www.weather.com/newscenter/hurri ... index.html

Oct 9, 2012 4:59 pm ET
INVEST 98L

- A broad area of persistent convection (showers & thunderstorms) in the central tropical Atlantic, at low latitudes to the east of northeastern South America, has been designated Invest 98L by the National Hurricane Center.

- It currently is not close to being a tropical cyclone, but will be monitored for signs of further organization into one as it heads to a position not far from the Lesser Antilles by the end of the week.

[cycloneye]

Another Bastardi Tweet.


@BigJoeBastardi

Finally some moist air in traditional atlantic breeding ground at 400 mb. should allow development on way nw

http://twitter.com/BigJoeBastardi/statu ... 96/photo/1

[cycloneye]

00z Best Track came out late but here it is.

AL, 98, 2012101000, , BEST, 0, 89N, 504W, 30, 1009, LO

http://ftp.nhc.noaa.gov/atcf/tcweb/inve ... 012.invest