Tropical Depression Isaac:

[rselby0654]

Eyewall is contracting...

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 27th day of the month at 21:50Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 306)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 27
Observation Number: 14
A. Time of Center Fix: 27th day of the month at 21:08:20Z
B. Center Fix Coordinates: 26°28'N 86°09'W (26.4667N 86.15W)
B. Center Fix Location: 249 miles (401 km) to the WSW (245°) from Tampa, FL, USA.
C. Minimum Height at Standard Level: 1,276m (4,186ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 54kts (~ 62.1mph)
E. Location of the Estimated Maximum Surface Wind: 46 nautical miles (53 statute miles) to the SE (128°) of center fix
F. Maximum Flight Level Wind Inbound: From 240° at 72kts (From the WSW at ~ 82.9mph)
G. Location of Maximum Flight Level Wind Inbound: 64 nautical miles (74 statute miles) to the SE (129°) of center fix
H. Minimum Sea Level Pressure: 982mb (29.00 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 18°C (64°F) at a pressure alt. of 1,525m (5,003ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 22°C (72°F) at a pressure alt. of 1,523m (4,997ft)
K. Dewpoint Temp & Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the west
M. Eye Shape & Diameter: Circular with a diameter of 15 nautical miles (17 statute miles)
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: 1 nautical mile
Remarks Section:
Maximum Flight Level Wind: 74kts (~ 85.2mph) in the southwest quadrant at 19:52:30Z
Maximum Flight Level Temp: 22°C (72°F) which was observed 9 nautical miles to the ESE (120°) from the flight level center

This may be a dumb question but what does the eyewall contracting mean?

[MontgomeryCoWx]

It's winding up for a pop

[Bluefalcon]

Recon Mission #27

1st Center Fix Coordinates: 26°07'N 85°59'W (26.1167N 85.9833W)
3rd Center Fix Coordinates: 26°28'N 86°09'W (26.4667N 86.15W)

Distance traveled: 27 miles
Heading: 310-315 degrees (NW)
Speed: Appx. 8 MPH

[srainhoutx]

This may be a dumb question but what does the eyewall contracting mean?

No dumb questions here... It a signal that the eyewall is getting smaller or more compact and is indicative of a potential strengthening period. I'll also note that new convection is developing near the center as well.

[redneckweather]

jcarr...give it up bro. Isaac is not coming here. 2 days out and hardly any modeling brings it anywhere close to us.

Let's have this discussion come Thursday shall we?

[biggerbyte]

WRONG. Isaac is NOT heading in our direction and we ARE out of the woods. That is a FACT.

Wow you must have a crystal bal! And it's a FACT..wow. I am of the "we are not out of the woods until it makes landfall" school of thought.

LOL! That is funny.

Actually, it is. The forecast, however, is still for that turn towards LA. Has not happened yet.
We will see.

[sambucol]

Just look at the radar loop and you be the judge. It's not rocket science.

Well, thanks. I think.

[srainhoutx]

Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 27th day of the month at 21:51Z
Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 28
Observation Number: 08
A. Time of Center Fix: 27th day of the month at 21:25:41Z
B. Center Fix Coordinates: 26°27'N 86°12'W (26.45N 86.2W)
B. Center Fix Location: 253 miles (407 km) to the WSW (245°) from Tampa, FL, USA.
C. Minimum Height at Standard Level: Not Available
D. Estimated (by SFMR or visually) Maximum Surface Wind: 49kts (~ 56.4mph)
E. Location of the Estimated Maximum Surface Wind: 19 nautical miles (22 statute miles) to the NE (36°) of center fix
F. Maximum Flight Level Wind Inbound: From 120° at 52kts (From the ESE at ~ 59.8mph)
G. Location of Maximum Flight Level Wind Inbound: 32 nautical miles (37 statute miles) to the NNE (33°) of center fix
H. Minimum Sea Level Pressure: 981mb (28.97 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 16°C (61°F) at a pressure alt. of 2,450m (8,038ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 20°C (68°F) at a pressure alt. of 2,446m (8,025ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 14°C (57°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the east
M. Eye Shape & Diameter: Circular with a diameter of 25 nautical miles (29 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: Other - Not surface, 1500ft, 925mb (if vortex is newer than about mid 90's; see note for more), 850mb, 700mb, 500mb, 400mb, 300mb or 200mb
O. Fix Determined By / Fix Level (Undecoded): 1 / 1 nm
Remarks Section:
MAX OUTBOUND FL WIND AND MAX FL WIND 56 KT SW QUAD 21:40:26Z
SONDE SFC WIND 15KTS

[ticka1]

Let's make our own predictions for landfall - time and place. I am saying Wednesday morning Morgan City. Wanted to say Lake Charles but I split the difference and its Morgan City.

[biggerbyte]

Just look at the radar loop and you be the judge. It's not rocket science.

Well, thanks. I think.

Hmmm! Maybe we all should be careful of the words we use to make our point. Jcarr would probably concur. We don't want to seem confrontational.. No?

Anyway, the point is, no one is out of the woods until this system is actually in the woods. Models are to be changed.. Daily.. Sometimes several times a day. If we could rely on the models with Isaac, he would be inland over the Florida pan handle already.

[jeff]

The exact point of landfall is not what is important at this point. The large area of TS force winds for a prolonged period of time into the concave shape of SW MS is going to produce a fairly significant storm surge (8-12 ft). The impacts are going to be far reaching. As long as the center goes in W of the mouth of the MS River there is going to be some decent water level rise into SW MS and SE LA including Lake Pontchartrain and into the lower MS Delta up against the western levees in New Orleans.

Additionally I highly doubt this storm will make it anywhere close to TX and any impacts if any at all will be very minimal.

[Bluefalcon]

Recon #27 just punched the center for the 4th time. Position a little more west than north. Vortex to follow.

[unome]

here's the 6 pm update from a Texas Tech PhD with 25 yrs in at the NHC, Ed Rappaport

http://www.nhc.noaa.gov/audio/201208272206.mp3

[Bluefalcon]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 27th day of the month at 22:25Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 306)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 27
Observation Number: 18
A. Time of Center Fix: 27th day of the month at 22:11:50Z
B. Center Fix Coordinates: 26°31'N 86°19'W (26.5167N 86.3167W)
B. Center Fix Location: 257 miles (414 km) to the WSW (247°) from Tampa, FL, USA.
C. Minimum Height at Standard Level: 1,272m (4,173ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 57kts (~ 65.6mph)
E. Location of the Estimated Maximum Surface Wind: 15 nautical miles (17 statute miles) to the WNW (303°) of center fix
F. Maximum Flight Level Wind Inbound: From 29° at 47kts (From the NNE at ~ 54.1mph)
G. Location of Maximum Flight Level Wind Inbound: 15 nautical miles (17 statute miles) to the WNW (303°) of center fix
H. Minimum Sea Level Pressure: 982mb (29.00 inHg)I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 19°C (66°F) at a pressure alt. of 1,523m (4,997ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 22°C (72°F) at a pressure alt. of 1,538m (5,046ft)
K. Dewpoint Temp & Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the east
M. Eye Shape: Elliptical (oval shaped)M. Orientation of Major Axis in Elliptical Eye: 60° to 240° (ENE to WSW)
M. Length of Major Axis in Elliptical Eye: 30 nautical miles (35 statute miles)
M. Length of Minor Axis in Elliptical Eye: 20 nautical miles (23 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 0.5 nautical miles
Remarks Section:
Maximum Flight Level Wind: 74kts (~ 85.2mph) in the southwest quadrant at 19:52:30Z
Maximum Flight Level Wind Outbound: 51kts (~ 58.7mph) in the east quadrant at 22:17:40Z
Maximum Flight Level Temp: 22°C (72°F) which was observed 6 nautical miles to the NW/NNW (326°) from the flight level center

[srainhoutx]

Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 27th day of the month at 23:11Z
Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 28
Observation Number: 19
A. Time of Center Fix: 27th day of the month at 22:44:15Z
B. Center Fix Coordinates: 26°34'N 86°21'W (26.5667N 86.35W)
B. Center Fix Location: 258 miles (415 km) to the WSW (248°) from Tampa, FL, USA.
C. Minimum Height at Standard Level: 2,973m (9,754ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 48kts (~ 55.2mph)
E. Location of the Estimated Maximum Surface Wind: 18 nautical miles (21 statute miles) to the SE (139°) of center fix
F. Maximum Flight Level Wind Inbound: From 212° at 70kts (From the SSW at ~ 80.6mph)
G. Location of Maximum Flight Level Wind Inbound: 37 nautical miles (43 statute miles) to the SE (132°) of center fix
H. Minimum Sea Level Pressure: 981mb (28.97 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 12°C (54°F) at a pressure alt. of 3,054m (10,020ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 16°C (61°F) at a pressure alt. of 3,073m (10,082ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 11°C (52°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Poorly Defined
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 700mb
O. Fix Determined By / Fix Level (Undecoded): 1 / 1 nm
Remarks Section - Remarks That Were Decoded...
Maximum Flight Level Wind: 70kts (~ 80.6mph) in the southeast quadrant at 22:34:49Z
Maximum Flight Level Wind Outbound: 52kts (~ 59.8mph) in the northwest quadrant at 22:51:23Z
Maximum Flight Level Temp: 16°C (61°F) which was observed 7 nautical miles to the SE (145°) from the flight level center
Remarks Section - Additional Remarks...
SLP EXTRAP FROM 10K FT

[cristina99]

I enjoy reading what everyone has to say. I saw that "weeble wobble" on an earlier forecast and it would weeble to the west then back. Those of us who have lived anywhere along the Texas coast knows that storms have minds of their own. Mother Nature doesn't really follow the forecasts sometimes. I think everyone needs to be prepared. By some weird reason, it could swing west and go in south Texas.

[cristina99]

Watching Dr. Frank and he says it wouldn't have to move much westward to make a Texas coast hit. He said he isn't letting his guard down yet.

[Rip76]

Looks like it's pulling N'ward now.

[biggerbyte]

You are seeing a wobble again, Rip. Lay the grid down on the online map you are viewing and watch the system as a whole.

[biggerbyte]

Amen to that.