Tropical Depression GABRIELLE:Discussions and Images

[Brent]

Almost perfectly round:

First one to say it has gone annular gets banned

[Derek Ortt]

surface center still appears SE of the convection based upon nighttime visible

[HURAKAN]

Latest:

[brunota2003]

Chad ---> Has TS Gabrielle gone Annular? I think it might be Nope, there are indeed rainbands invovled with it.

[MiamiensisWx]

I concur with AJC3. Although it may seem like the LLC has relocated to a position under the convection, it is probably an illusion. ILM radar (latest image) indicates a broader circulation, so the apparent developing "band" and rotation could be a MLC and/or mesoscale feature. I still think the LLC is further south and closer to the edge of the convection, but it could eventually relocated northward. Overall, the TPC's forecast is on track, IMO. I think the LLC is near 33.1N and 75.1W (based on shortwave imagery).

[gotoman38]

surface center still appears SE of the convection based upon nighttime visible

Hi Derek! Do you have a landfall estimate? Anyone else?

[Tstormwatcher]

This storm is beginning to act like Ophelia did. Moving northwest then west and finally paralleling the coast which is what I belive Gab will do. I just hope it brings us at least a couple of inches of rain.

[canetracker]

http://www.storm2k.org/phpbb2/viewtopic.php?f=29&t=97813
Derek just posted his thoughts of landfall in the above thread.

[brunota2003]

This storm is beginning to act like Ophelia did. Moving northwest then west and finally paralleling the coast which is what I belive Gab will do. I just hope it brings us at least a couple of inches of rain.

Looks like your hopes might come true:

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
935 PM EDT SAT SEP 8 2007

.SYNOPSIS...
-- Changed Discussion --
TROPICAL STORM GABRIELLE WILL APPROACH THE AREA FROM THE SE
THROUGH SUNDAY. THE STORM IS EXPECTED TO STRENGTHEN OVER THE NEXT
24 HRS. CURRENT FORECASTS MAKE LANDFALL NEAR CAPE HATTERAS LATE
SUNDAY AFTERNOON AS A STRONG TROPICAL STORM THEN MOVES OFFSHORE OFF
THE NORTHERN OUTER BANKS EARLY MONDAY MORNING. A COLD FRONT WILL
MOVE IN FROM THE NW LATE TUE AND STALL OVER THE AREA WED AND THU.
THE FRONT WILL RETURN N AS A WARM FRONT FRI.
-- End Changed Discussion --


&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
LATEST SUCCESSION OF UPPER AIR REPORTS INDICATES THAT THE
ATMOSPHERE IS RAPIDLY MOISTENING AS EVIDENCED BY PW RISING TO 1.78"
THIS EVENING. INITIAL RAIN BANDS ASSOCIATED WITH GABRIELLE ARE
STARTING TO IMPINGE ON THE SOUTHERN OUTER BANKS REGION SOUTH OF
HATTERAS. WE EXPECT RAINFALL TO GRADUALLY INCREASE FROM THE OUTER
BANKS TO THE CRYSTAL COAST AFTER MIDNIGHT WITH RAINFALL SPREADING
INLAND BY 12Z. CONVECTIVE CLUSTER ON WEST SIDE OF GABRIELLE HAS
BEEN INCREASING WITH COOLING CLOUDS TOPS...PERHAPS INDICATING THE
BEGINNING OF THE EXPECTED INTENSIFICATION. ON THE NEGATIVE SIDE IT
STILL LOOKS LIKE AT LEAST THE EASTERN PORTION OF THE LOW LEVEL CIRCULATION
IS EXPOSED...INDICATING THAT THE UPPER LOW TO IT`S SW IS STILL
PRODUCING SOME SHEAR. ALSO THE STORM IS AN ENVIRONMENT OF VERY DRY
MID LEVEL AIR AS SEEN IN WATER VAPOR IMAGERY. THE FORECAST OF SLOW
INTENSIFICATION BUT REMAINING BELOW HURRICANE STRENGTH IS
SEEMS REASONABLE BASED ON THESE OBSERVATIONS AND IS ALSO
SUPPORTED BY THE SHIPS/GFDL AND HURRICANE WRF MODELS.

THE TREND IN THE TRACK MODELS IS TO THE RIGHT THE PAST 24 HOURS
WITH THE STORM CENTER BRUSHING THE COAST OR PERHAPS BRIEFLY
CROSSING THE OUTER BANKS SUNDAY AFTERNOON. THIS TREND IS ALSO
SUPPORTED BY THE LATEST UPPER AIR ANALYSIS WHICH SHOWS A
PRONOUNCED WEAKNESS IN THE 500 MB HEIGHT FIELDS TO THE WEST WHICH
IS EXPECTED TO STEER OR PICK UP THE SYSTEM ON SUNDAY.

RAINFALL WITH THE THE STORM WILL LIKELY BE HEAVIEST ACROSS THE
OUTER BANKS AND CRYSTAL COAST WITH A SHARP GRADIENT AS YOU HEAD WEST
AND NW. AREAS WEST OF HIGHWAY 17 WILL PROBABLY RECEIVE A 1/2 INCH OR
LESS OF RAINFALL AND WILL HAVE TO AWAIT THE ARRIVAL OF A FRONTAL
SYSTEM MID WEEK FOR SOME MUCH NEEDED RAINFALL. COASTAL LOCATIONS
WILL LIKELY RECEIVE 1-3 INCHES WITH ISOLATED HEAVIER AMOUNTS.

CLOUDS WILL BE ON THE INCREASE OVERNIGHT AND THIS WILL LEAD TO A
LITTLE WARMER OVERNIGHT LOWS WITH READINGS IN THE MIDDLE TO UPPER
60S EXPECTED.

[Ptarmigan]

Gabrielle has improved. It's just one circular cloud.

[ncbird]

I think it's going to come in around the same spot as Isabel. Maybe a bit further south than that, perhaps AB or Emerald Isle or thereabouts during which it'll make it's swing north and northeast. That would help dump some rain here in New Bern!

Nerver thought I would wish a Tropical System (well in this case sub-tropical) would actually come my way until now, but a little rain would be great (drools).

[UpTheCreek]

I think it's going to come in around the same spot as Isabel. Maybe a bit further south than that, perhaps AB or Emerald Isle or thereabouts during which it'll make it's swing north and northeast. That would help dump some rain here in New Bern!

Nerver thought I would wish a Tropical System (well in this case sub-tropical) would actually come my way until now, but a little rain would be great (drools).

I echo that, but all things in moderation, neighbor!

[gotoman38]

Same here!

RECON is transmitting from the runway

[hurricanewatcher]

<<<<<<<<<<<< gabbys cheer squad here in eastern NC go gabby go go gabby go... !!!!!!!!!! wooooooo hoooooooooo (sick of my brown lawn and dieing trees - roses are long gone)

[HURAKAN]

Latest:

[UpTheCreek]

<<<<<<<<<<<< gabbys cheer squad here in eastern NC go gabby go go gabby go... !!!!!!!!!! wooooooo hoooooooooo (sick of my brown lawn and dieing trees - roses are long gone)

Well, we're better off now than we were this morning. I did read Derek's forecast though, looks like the best we can hope for is a small soaking here in New Bern.

Still celebrating though!!!

[Tommedic]

Just released on Wilmington Forecast Text:
"
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --SWATH OF RAIN FROM GABRIELLE IS NEARING THE 40NM MARK EAST OF CAPE
FEAR...WHILE THE DEEPER CONVECTION IS STILL APPROXIMATELY 70NM
OFFSHORE. THE LEAD BANDS CONTINUE TO DISSIPATE AS THEY RUN INTO THE
DRY AIRMASS IN PLACE ALONG THE COAST. THE COLUMN WILL GRADUALLY
MOISTEN AS THE STORM GETS CLOSER TO THE COAST. SUBSEQUENTLY...ALONG
WITH INCREASING LOW-LEVEL CONVERGENCE THE CHANCES FOR SHRA/TSRA LOOK
GOOD...ESPECIALLY ACROSS COASTAL PORTIONS OF THE CAPE FEAR AREA.
RAINFALL HAS BEEN IMPRESSIVE ON THE WEST SIDE OF THE CIRCULATION AND
IF THE TRACK IS ADJUSTED A NOTCH TO THE WEST WILL NEED TO INCREASE
WINDS...POPS...AND QPF ACROSS THE CAPE FEAR ZONES. WILL MAKE FINAL
GRID ADJUSTMENTS AFTER NHC CONF CALL."

[OuterBanker]

Seems Newport thinks it will cross Hatteras and exit on top of us. Come on rain.

[philnyc]

it is it west of the forecast track what is the implication about landfall??

I think if you look at the whole extent of Gabrielle's circulation, you'll come to the conclusion that the vortex being shown on radar is most likely a mesoscale feature rotating westward around the north side of the circulation.

Another point... looking at IR, the NW flank of the CDO is not making much progress toward the northwest and seems to be flattening some. I think there are two reasons for this: 1) The ridge, which was narrow to begin with, is eroding and retreating eastward. Hence, the system is slowing...which most likely is in advance of the forecast sharp turn toward the north and northeast. 2) Have a look-see at the dew points over NC...mostly lower to middle 60s with a smattering of mid-upper 50s. Dew points AOA 70F are pretty much confined to the OBX. So...there's some pretty dry air over the state (those who are living through the ongoing drought don't really need to be told this), and any rainfall being advected into this air mass, be it convective or stratiform debris, at least initially, is probably going to "sacrifice" itself moistening up the air mass. The most pronounced effects of Gabrielle look like they will be confined to eastern NC...pretty much what is being forecast.

I think you are right about the mesoscale vortex, especially given that it appears to be tracking due west at the moment. What will be interesting is to see how this continues to evolve tonight, as the circulation is pretty vigorous.

What does the due west movement in the mesoscale circulation mean for overall movement?

[Thunder44]

QS pass at 23:36 UTC shows the LLC further south of rotation seen on radar: