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kellybell4770 wrote:seems to me that because the models seem to be all over the place (first thing this morning they were ALL pointed toward central LA and just now they are split in half again) we should not completely write off the possibility of rain - everyone knows how unpredictable these things can be! (trying to remain the ever optimist)

I think your right Kelly! They look mighty split to me! TX might still be in the game here! AND...to my "untrained" eyes, it looks to me that NHC track is tooo far to the east comparing to the latest models.....hmmm..

djmike wrote:

kellybell4770 wrote:seems to me that because the models seem to be all over the place (first thing this morning they were ALL pointed toward central LA and just now they are split in half again) we should not completely write off the possibility of rain - everyone knows how unpredictable these things can be! (trying to remain the ever optimist)

I think your right Kelly! They look mighty split to me! TX might still be in the game here! AND...to my "untrained" eyes, it looks to me that NHC track is tooo far to the east comparing to the latest models.....hmmm..

like srain always says "stay tuned'

Dare I say, back on the bandwagon?

No, do not jump back on the bandwagon because all that will do is piss you off even more. Where the hell is my zanax!

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 2nd day of the month at 14:33Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 306)
Tropical Depression: Number 13 (flight in the North Atlantic basin)
Mission Number: 2
Observation Number: 07
A. Time of Center Fix: 2nd day of the month at 12:33:40Z
B. Center Fix Coordinates: 27°37'N 90°55'W (27.6167N 90.9167W) (View map)
B. Center Fix Location: 171 miles (275 km) to the SSW (198°) from New Orleans, LA, USA.
C. Minimum Height at Standard Level: 1,469m (4,820ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 27kts (~ 31.1mph)
E. Location of the Estimated Maximum Surface Wind: 8 nautical miles (9 statute miles) to the NNE (21°) of center fix
F. Maximum Flight Level Wind Inbound: From 120° at 12kts (From the ESE at ~ 13.8mph)
G. Location of Maximum Flight Level Wind Inbound: 8 nautical miles (9 statute miles) to the NNE (19°) of center fix
H. Minimum Sea Level Pressure: 1006mb (29.71 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 18°C (64°F) at a pressure alt. of 1,521m (4,990ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 19°C (66°F) at a pressure alt. of 1,524m (5,000ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 8°C (46°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 2 nautical miles
Remarks Section:
Maximum Flight Level Wind: 37kts (~ 42.6mph) in the north quadrant at 12:08:10Z

With dry air and shear off to the west of the dep... disturbance... my grasping-at-straws hope is that it will stay shallow enough to not be picked up by the trough, and drift generally NW or NNW over the next 72 hours, giving us a little more chance at a few showers.

In the latest IR loop, the western edge of TD13 appears to move about 150 to the west over the last 7 hours. Do you think this is because the storm is rapidly expanding or is there some meaningful movement there?

http://www.ssd.noaa.gov/goes/flt/t1/flash-avn.html

redneckweather wrote:No, do not jump back on the bandwagon because all that will do is piss you off even more. Where the hell is my zanax!

Redneck, back S-L-O-W-L-Y away from the computer

In all seriousness, I feel your frustration, I really do!

texasrattler wrote:In the latest IR loop, the western edge of TD13 appears to move about 150 to the west over the last 7 hours. Do you think this is because the storm is rapidly expanding or is there some meaningful movement there?

http://www.ssd.noaa.gov/goes/flt/t1/flash-avn.html

it looks to me like shear may be relaxing a bit and the ball of convection is beginning to move over center. anyone else?

BULLETIN
TROPICAL DEPRESSION THIRTEEN ADVISORY NUMBER 4
NWS NATIONAL HURRICANE CENTER MIAMI FL AL132011
1000 AM CDT FRI SEP 02 2011

...DEPRESSION NEARLY STATIONARY SOUTH OF THE LOUISIANA COAST...
RAINBANDS MOVING ACROSS MUCH OF SOUTHEASTERN LOUISIANA...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...27.3N 91.5W
ABOUT 190 MI...310 KM SW OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 230 MI...370 KM SE OF PORT ARTHUR TEXAS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

NONE

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* PASCAGOULA MISSISSIPPI WESTWARD TO SABINE PASS TEXAS...INCLUDING
THE CITY OF NEW ORLEANS...LAKE PONTCHARTRAIN...AND LAKE MAUREPAS

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN THE
NEXT 24 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA ...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY
YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1000 AM CDT...1500 UTC...THE CENTER OF TROPICAL DEPRESSION
THIRTEEN WAS LOCATED NEAR LATITUDE 27.3 NORTH...LONGITUDE 91.5 WEST.
THE DEPRESSION IS DRIFTING TOWARD THE NORTHWEST NEAR 2 MPH...4 KM/H.
A CONTINUED SLOW AND POSSIBLY ERRATIC MOTION TOWARD THE NORTHWEST
OR NORTH IS EXPECTED TODAY AND SATURDAY. ON THE FORECAST TRACK...
THE CENTER OF THE CYCLONE IS EXPECTED TO APPROACH THE COAST OF
SOUTHERN LOUISIANA DURING THE WEEKEND.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. GRADUAL STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS
AND THE DEPRESSION COULD BECOME A TROPICAL STORM LATER TODAY. WINDS
OF TROPICAL STORM FORCE ARE BEING REPORTED ON OIL RIGS NORTH AND
EAST OF THE CENTER AT ELEVATIONS OF A FEW HUNDRED FEET.

THE ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON REPORTS FROM NEARBY
OIL RIGS AND AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT IS 1005
MB...29.68 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...THE DEPRESSION IS EXPECTED TO PRODUCE TOTAL RAIN
ACCUMULATIONS OF 10 TO 15 INCHES OVER SOUTHERN LOUISIANA...SOUTHERN
MISSISSIPPI...AND SOUTHERN ALABAMA THROUGH SUNDAY...WITH POSSIBLE
ISOLATED MAXIMUM AMOUNTS OF 20 INCHES. THESE RAINS ARE EXPECTED TO
CAUSE EXTENSIVE FLOODING.

STORM SURGE...A STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 2
TO 4 FEET ABOVE GROUND LEVEL ALONG THE NORTHERN GULF COAST IN AREAS
OF ONSHORE FLOW.

WIND...TROPICAL STORM CONDITIONS ARE EXPECTED TO FIRST REACH THE
COAST WITHIN THE WARNING AREA THIS EVENING...MAKING OUTSIDE
PREPARATIONS DIFFICULT OR DANGEROUS.

TORNADOES...ISOLATED TORNADOES ARE POSSIBLE OVER PORTIONS OF
SOUTHERN LOUISIANA TONIGHT.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...100 PM CDT.
NEXT COMPLETE ADVISORY...400 PM CDT.

$$
FORECASTER STEWART

there's a lot going on in this loop.

http://www.ssd.noaa.gov/goes/east/gmex/flash-vis.html

RECON is having a difficult time finding one 'center', but rather multiple vortices rotating within the very broad low level circulation. These 'eddies' are common in a developing cyclone. We will see where the dominate center sets up in the hours ahead.

Looking at the visible loop...the western vortex seems to be dominate right now with the convection to the west starting to fire, and wrap around.

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

hmmm....

edit to add: site to find this info directly is http://tropic.ssec.wisc.edu/ , hover mouse over "North Atlantic" in Regional Real-Time Products, choose "Winds & Analysis" & then the data you wish to view in the rectangular box. Notice that you can also add 3 or subtract 3 hrs to view previous data. Also, once you select the product, if you click "Product Info" you can learn more about it - love this site

our little TD - here is 850 mb level

Rip76 wrote:there's a lot going on in this loop.

http://www.ssd.noaa.gov/goes/east/gmex/flash-vis.html

Hi everyone - I've been glued to the forum since late last week about our little TD here! I agree Rip76, looking at the loop it seems to me that the center is relocating south of the TX/LA boarder and that the system as a whole looks to be shifting more to the NW. I'm still holding out hope that we will at least get SOME rain

Hi guys! I am trying to have a "glass half full" approach to this system bringing us some rain, but it's getting more and more difficult to stay optimistic at this point. So, that brings me to this question....since this little guy is sitting out there churning up the waters, is it going to cool the water temp down enough that we are going to have to wait for it to warm back up before another spin up can occur??

Rhodesk75 wrote:Hi guys! I am trying to have a "glass half full" approach to this system bringing us some rain, but it's getting more and more difficult to stay optimistic at this point. So, that brings me to this question....since this little guy is sitting out there churning up the waters, is it going to cool the water temp down enough that we are going to have to wait for it to warm back up before another spin up can occur??

As we saw in 2008 after Gustav, Ike seemed to do rather well with the SST's in Gulf.

Folks, the vortex southeast of the Tx/La border cannot be ignored. Look at how the activity to its east and north seem to want to wrap around it:

http://wxweb.meteostar.com/models/noaap ... /SYS/COMP/

Jeff Masters at Weather Underground posted an update in his blog http://www.wunderground.com/blog/JeffMa ... rynum=1913

here's the portion on TD13, without graphics:

By Dr. Jeff Masters
Published: 3:35 PM GMT on September 02, 2011

Tropical Depression Thirteen formed last night over the Northern Gulf of Mexico and is slowly intensifying, but isn't in a hurry to go anywhere. What TD 13 will do is dump torrential rains along the northern Gulf Coast over the next three or more days. So far, rain amounts along the coast have mostly been below one inch. At New Orleans Lakefront Airport, just 0.32" inches of rain had fallen from TD 13 as of 10 am CDT. Some coastal regions have received up to two inches, according to radar rainfall estimates. TD 13 is generating a large area of 30 - 35 mph winds over the Gulf of Mexico. At 7:20 am CDT, winds at the Mississippi Canyon 711 oil rig were southeast at 47 mph. This is above tropical storm force, but the wind instrument was 348 feet (106 m) above the ocean surface, and winds near the surface were probably considerably lower, near 35 mph. Latest surface wind observations from an Air Force hurricane hunter aircraft support leaving TD 13 as a tropical depression. Long range radar out of Mobile, Alabama shows heavy rain showers building along the northern Gulf Coast, but these rain showers are not well-organized into spiral bands. Strong upper-level winds out of the west-northwest are creating a moderate 10 - 20 knots of wind shear over TD 13, keeping the storm's heavy thunderstorms disorganized and pushed to the east side of the storm. However, latest satelllite loops show TD 13 is becoming increasingly organized, with a respectable spiral band forming on the southeast side, and an increase and areal coverage of heavy thunderstorm activity. This is very likely to be a tropical storm later today.

Forecast for TD 13
TD 13's large size, ill-formed circulation center, and the presence of dry air on its west side due to an upper-level trough of low pressure argue against rapid intensification of the storm for the next three days. Also tending to slow intensification will be the slow movement of the storm, which will allow cold water from the depths to rise to the surface, thanks to wind and wave action. Tropical cyclones strongly cool the water's surface when they pass over it, as seen in the time vs. depth chart of sea surface temperatures during Hurricane Irene's passage along the New Jersey coast (Figure 3.) However, the Gulf of Mexico has some very warm waters near TD 13 that extend to great depth (Figure 4), so the surface cooling imparted by TD 13 will be less than that seen for Hurricane Irene. As TD 13 moves closer to the coast, more and more of its circulation will be over land, which will also slow intensification. NHC's 11 am EDT wind probability forecast for TD 13 gave the storm a 23% chance of intensifying into a hurricane by Sunday. Assuming TD 13 does not attain hurricane strength, wind damage and storm surge damage will likely not be the main concern--fresh water flooding from heavy rains will be the most dangerous impact. Also of concern is the possibility of tornadoes. NOAA's Storm Prediction Center is currently not highlighting the Gulf Coast in their "slight risk" area for severe weather, due to the lack of enough solar heating to create instability. However, there will be plenty of wind shear in the lower part of the atmosphere that can potentially create spin in the coastal thunderstorms, and it is possible that as TD 13 intensifies, it may be able to generate several dozen tornadoes.

Coastal Louisiana, Mississippi, Alabama, and the extreme western Panhandle of Florida will likely receive very heavy flooding rains that will intensify Saturday and peak on Sunday. These rains should be able to put out the stubborn marsh fire east of New Orleans that has brought several days of air quality alerts to the city, but may cause moderate to severe flooding problems in other areas. The latest rainfall forecast from NOAA Hydrological Prediction Center shows that a large area of 15+ inches of rain is expected over Southeast Louisiana and coastal Mississippi. The region is under moderate drought, so flooding problems will be delayed compared to what we'd normally expect from heavy rains of over a foot. Flash flood watches are posted for New Orleans and surrounding areas, and rainfall amounts of 1 - 3 inches per hour are possible in some of the heavier rain squalls. Ocean temperatures are near record warmth, 88°F (31°C), which will provide plenty of moisture for heavy rains, and plenty of energy to help TD 13 strengthen into a strong tropical storm. Steering currents will be weak in the Gulf this weekend and early next week, which will likely make the motion of TD 13 erratic at times.