Tropical Depression Isaac:

[djmike]

I think the NHC is really being careful with the one. With the disagreement with the models, I think they want to be as prudent as possible before going the next step. At least that is what I am thinking and I am just a weather watcher.

I have to agree with you there Tireman...

But..I would like to know if its coming my way too since it's less than 12 hours from landfall. I STILL feel they will make a change. It MIGHT even be AFTER landfall....

[tireman4]

I think the NHC is really being careful with the one. With the disagreement with the models, I think they want to be as prudent as possible before going the next step. At least that is what I am thinking and I am just a weather watcher.

I have to agree with you there Tireman...

But..I would like to know if its coming my way too since it's less than 12 hours from landfall. I STILL feel they will make a change. It MIGHT even be AFTER landfall....

Indeed. Indeed

[JackCruz]

So are we out of the woods yet? Are any of the models showing a westward movement after making landfall? I don't remember which model, I think on Sunday either the GFS or the Euro showed it making landfall in LA and then move west across to Houston.

[MRG93415]

So are we out of the woods yet? Are any of the models showing a westward movement after making landfall? I don't remember which model, I think on Sunday either the GFS or the Euro showed it making landfall in LA and then move west across to Houston.

Honeslty Jack, I have no idea...There are alot of things going on right now and I am waiting to see what is what. I know Doc is suppose to be on the news at 4, 5, 6 AND 10..

[cristina99]

This storm sure is throwing some for a loop. Channel 2 did say it was a slow moving storm and that worries me. I am anxious to see what Dr. Frank says at 5 -- and see if his information changes at 6 and 10. I feel for those in LA. I wondered if there was a chance it could move west once making landfall -- someone told me it didn't look likely. This is so tense. Someone must believe there might be some changes because the Spring, Texas WM has bottles of water stacked up just about everywhere in their store -- we saw it in the area where the baskets were this morning. Although no one wants it to come our way, we still need to be cautious. Does anyone know if there is an off chance it could make a last minute (11th hour so to speak) turn west and hug the coast like some said earlier. I think my young cats know something is up -- at least one of them. She is running around here and chatting.

[djmike]

So are we out of the woods yet? Are any of the models showing a westward movement after making landfall? I don't remember which model, I think on Sunday either the GFS or the Euro showed it making landfall in LA and then move west across to Houston.

Honeslty Jack, I have no idea...There are alot of things going on right now and I am waiting to see what is what. I know Doc is suppose to be on the news at 4, 5, 6 AND 10..

Be sure and post what "The Doc" has to say about Isaac. Really intrested to hear his take on todays models. If anyone knows about storms! It's DOC!

[djmike]

MPO...I honestly feel at this point, NHC will not change their track until after landfall, so they can show/prove that they were "correct" all along at predicting landfall. BUT after landfall...again, MPO...I feel they will make a change west! Somehow, someway, somewhere....

[jasons2k]

Most likely, they are not changing the track because they have a good handle on the situation....

[jasons2k]

Posted on Eric Berger's blog on Chron.com:

HOUSTON EFFECTS

Forecasters at the Houston/Galveston office of the National Weather Service have been grappling with the question of whether Houston will see some effects from Isaac.

I just spoke with Gene Hafele, the office’s meteorologist in charge, and he told me, “We’re leaning toward some effects, and we’re increasing the chance of rain and winds.”

This means, for areas east of Interstate 45, there will be a 40 percent chance of showers due to Isaac from Wednesday afternoon through Thursday. Inland winds also could creep up a bit, but not to dangerous levels. Areas west of I-45 will probably remain hot and dry for the remainder of the work week.

Offshore winds could approach tropical storm strength, Hafele said.

[SusieinLP]

East of 45 as in Beaumont or closer like Chambers county?

[srainhoutx]

Code: Select all

Product: NOAA Temp Drop (Dropsonde) Message (UZNT13 KWBC)
Transmitted: 28th day of the month at 22:12Z
Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)
Storm Number: 09
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 33 
Observation Number: 08

Part A...


Date: Near the closest hour of 22Z on the 28th day of the month
Highest Mandatory Level For Which Wind Was Reported: 700mb
Coordinates: 28.8N 89.1W 
Location: 100 miles (160 km) to the SE (145°) from New Orleans, LA, USA.
Marsden Square: 081 (About)

Level Geo. Height Air Temp. Dew Point Wind Direction Wind Speed 
971mb (28.67 inHg) Sea Level (Surface) 27.8°C (82.0°F) 27.3°C (81.1°F) 150° (from the SSE) 5 knots (6 mph) 
1000mb -268m (-879 ft) This level does not exist in this area of the storm above the surface level. 
925mb 428m (1,404 ft) 25.8°C (78.4°F) 25.7°C (78.3°F) 190° (from the S) 3 knots (3 mph) 
850mb 1,174m (3,852 ft) 22.4°C (72.3°F) 22.3°C (72.1°F) 180° (from the S) 4 knots (5 mph) 
700mb 2,851m (9,354 ft) 15.6°C (60.1°F) 14.6°C (58.3°F) 165° (from the SSE) 5 knots (6 mph) 

Information About Radiosonde:
- Launch Time: 22:00Z
- About Sonde: A descending radiosonde tracked automatically by satellite navigation with no solar or infrared correction.

Remarks Section...


Dropsonde Location: Dropped in eye.

Splash Location: 28.78N 89.06W
Splash Time: 22:04Z

Release Location: 28.77N 89.06W View map)
Release Time: 22:00:03Z

Splash Location: 28.78N 89.06W (
Splash Time: 22:04:18Z

Mean Boundary Level Wind (mean wind in the lowest 500 geopotential meters of the sounding):
- Wind Direction: 180° (from the S)
- Wind Speed: 4 knots (5 mph)

Deep Layer Mean Wind (average wind over the depth of the sounding):
- Wind Direction: 175° (from the S)
- Wind Speed: 3 knots (3 mph)
- Depth of Sounding: From 695mb to 970mb

Average Wind Over Lowest Available 150 geopotential meters (gpm) of the sounding:
- Lowest 150m: 159 gpm - 9 gpm (522 geo. feet - 30 geo. feet)
- Wind Direction: 165° (from the SSE)
- Wind Speed: 5 knots (6 mph)

Sounding Software Version: AEV 07450


Part B: Data For Significant Levels...


Significant Temperature And Relative Humidity Levels... 
Level Air Temperature Dew Point 
971mb (Surface) 27.8°C (82.0°F) 27.3°C (81.1°F) 
850mb 22.4°C (72.3°F) 22.3°C (72.1°F) 
695mb 15.2°C (59.4°F) 14.1°C (57.4°F) 

Significant Wind Levels... 
Level Wind Direction Wind Speed 
971mb (Surface) 150° (from the SSE) 5 knots (6 mph) 
850mb 180° (from the S) 4 knots (5 mph) 
695mb 175° (from the S) 3 knots (3 mph) 

[srainhoutx]

East of 45 as in Beaumont or closer like Chambers county?

Here was the full update, Susie...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
329 PM CDT TUE AUG 28 2012

.DISCUSSION...
A VERY HOT DAY ACROSS SOUTHEAST TEXAS WITH TEMPERATURES NEARING
100 DEGREES OVER THE NORTHWEST ZONES. HEAT INDEX VALUES ARE
BETWEEN 100 AND 105 DEGREES. ISOLATED SHRA WERE BEGINNING TO
DEVELOP OVER THE WESTERN THIRD OF THE REGION. ALL EYES ARE ON THE
NORTHERN GULF AS ISAAC GAINS IN STRENGTH. HURRICANE ISAAC IS STILL
EXPECTED TO MOVE INTO SOUTHERN LOUISIANA AND THEN TRACK NORTHWEST.
SYNOPTIC SCALE MODELS STILL DIFFER RATHER SIGNIFICANTLY ON THE
POSITION OF ISAAC AFTER LANDFALL WITH THE NAM AND GFS FURTHER WEST
THAN THE OFFICIAL HURRICANE TRACK AND THE ECMWF. STILL NOT
COMPLETELY COMFORTABLE DISCOUNTING THE THE NAM AND GFS SOLUTIONS.
WILL EXPAND LOWISH POPS A BIT FURTHER WEST ON WEDNESDAY AS MSTR
LEVELS INCREASE TO NEAR OR JUST ABOVE 2.00 INCHES BY LATE WEDS
AFTN. WINDS WILL INCREASE ON WEDNESDAY...ESPECIALLY NEAR THE
EXTREME UPPER TEXAS COAST. WIND SPEEDS WILL APPROACH WIND ADVISORY
CRITERIA ON WEDS AFTN. WILL DEFER TO MIDNIGHT SHIFT ON THE WIND
ADVISORY. PW VALUES INCREASE TO BETWEEN 2.2 AND 2.3 INCHES WED
NIGHT INTO THURSDAY. THE NAM AND GFS HINT AT SOME MODERATE TO
STRONG LOW LEVEL SPEED AND DIRECTIONAL CONVERGENCE ALONG THE COAST
AS THE REMNANTS OF ISAAC MOVE INLAND. CONFIDENCE IN THIS
CONVERGENCE ZONE OCCURRING IS LOW BUT STILL WORTH A MENTION IN
THE ZFP. WILL GO WITH CHANCE POPS WED NIGHT THROUGH THURSDAY. HPC
QPF VALUES ARE BETWEEN 2 AND 3 INCHES OVER THE EXTREME EASTERN
ZONES BY FRIDAY NIGHT. WITH THE EXPECTED CLOUD COVER AND
RAIN...WILL TRIM MAX TEMPS A BIT ON THURSDAY. COULD BE QUITE A
CONTRAST IN TEMPS BETWEEN THE EASTERN AND WESTERN ZONES.
CONDITIONS WARM UP FRIDAY THROUGH SUNDAY WITH MAX TEMPS BACK INTO
THE MID 90S. PW VALUES BRIEFLY PEAK NEAR 2.0 INCHES AGAIN OVER THE
WEEKEND...SO WILL MAINTAIN SLT CHANCE POPS BOTH SAT/SUN. UPPER
LEVEL RIDGING WILL BUILD INTO TEXAS EARLY NEXT WEEK SO WILL LEAN
VERY WARM AND DRY MON THROUGH WEDS. 43

[Belmer]

Have been staring at radar for about 10 minutes now. Clearly Isaac has made a nice NNW jog. Maybe even a wobble to the North. Looks to be nearing landfall within a few hours even though NHC doesn't have it making landfall till tomorrow morning. Wonder if Isaac is about to come to a complete stop here soon and start slowly making its way west/wnw later tonight?

As much as I don't want to see a huge natural disaster or loss of life to anyone. If Isaac had another day over some nice warm water, he sure would have intensified as winds seem to finally be catching up with the pressure. He has really gotten his act together in the past 6-8 hours.

[srainhoutx]

Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 28th day of the month at 22:21Z
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: 33
Observation Number: 09
A. Time of Center Fix: 28th day of the month at 21:59:55Z
B. Center Fix Coordinates: 28°46'N 89°03'W (28.7667N 89.05W)
B. Center Fix Location: 103 miles (166 km) to the SE (144°) from New Orleans, LA, USA.
C. Minimum Height at Standard Level: 2,917m (9,570ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: Not Available
E. Bearing & Range from Center of Estimated Maximum Surface Wind (Undecoded): 301 deg 1 nm
F. Maximum Flight Level Wind Inbound: From 83° at 80kts (From the E at ~ 92.1mph)
G. Location of Maximum Flight Level Wind Inbound: 45 nautical miles (52 statute miles) to the NNW (343°) of center fix
H. Minimum Sea Level Pressure: 971mb (28.67 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 12°C (54°F) at a pressure alt. of 3,061m (10,043ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 17°C (63°F) at a pressure alt. of 3,066m (10,059ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 13°C (55°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the southwest
M. Eye Shape & Diameter: Circular with a diameter of 40 nautical miles (46 statute miles)
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 Temp: 17°C (63°F) which was observed 7 nautical miles to the NE/ENE (56°) from the flight level center
Remarks Section - Additional Remarks...
MAX OUTBOUND FL WIND AND MAX FL WIND 91 KT NE QUAD 22:10:20Z

[cperk]

wxman57 yesterday you were happy when the GFS finally came to it's senses,well it's lost it's mind again on the 18z run.The GFS is hugging the coastline thru hour 48,and the NAM has checked it's self into the crazy house too.

[srainhoutx]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 28th day of the month at 22:47Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 308)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 32
Observation Number: 02
A. Time of Center Fix: 28th day of the month at 22:25:50Z
B. Center Fix Coordinates: 28°52'N 89°07'W (28.8667N 89.1167W)
B. Center Fix Location: 95 miles (153 km) to the SE (143°) from New Orleans, LA, USA.
C. Minimum Height at Standard Level: 1,178m (3,865ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 61kts (~ 70.2mph)
E. Location of the Estimated Maximum Surface Wind: 56 nautical miles (64 statute miles) to the WSW (237°) of center fix
F. Maximum Flight Level Wind Inbound: From 325° at 84kts (From the NW at ~ 96.7mph)
G. Location of Maximum Flight Level Wind Inbound: 59 nautical miles (68 statute miles) to the WSW (238°) of center fix
H. Minimum Sea Level Pressure: 970mb (28.64 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 15°C (59°F) at a pressure alt. of 1,532m (5,026ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 21°C (70°F) at a pressure alt. of 1,523m (4,997ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 18°C (64°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character (Undecoded): SPIRAL BAND
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Radar, Wind and Pressure
N. Fix Level: 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile
Remarks Section:
Maximum Flight Level Wind: 84kts (~ 96.7mph) in the southwest quadrant at 22:07:00Z
Maximum Flight Level Temp: 22°C (72°F) which was observed 30 nautical miles (35 statute miles) to the SW (233°) from the flight level

[srainhoutx]

I'm going to caution everyone about these 'center' fixes. There is a meso vort rotating within a larger 'eye'. The general trends has been a bit more W than N. Some be mindful of that. We saw the same thing in Ike except there were 2-3 of those meso vorts rotating within Ike's very large eyewall.

[srainhoutx]

BULLETIN
HURRICANE ISAAC INTERMEDIATE ADVISORY NUMBER 31A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
600 PM CDT TUE AUG 28 2012

...CENTER OF ISAAC NEARING THE COAST OF SOUTHEAST LOUISIANA...STORM
SURGE FLOODING ALREADY OCCURRING...


SUMMARY OF 600 PM CDT...2300 UTC...INFORMATION
----------------------------------------------
LOCATION...28.9N 89.2W
ABOUT 15 MI...25 KM SSW OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 95 MI...150 KM SE OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...970 MB...28.64 INCHES


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

NONE.

[Scott747]

For those interested...

Didn't have time to join my chase partner but he is currently located in Galliano just NW of the current center. We're tracking an potentially developing inner core and hoping for a tug to the W in case it were to become the dominant feature.

Location of the chase thread is located in my sig if anyone would like to follow along.

So far he has had gusts in the upper 50's.

[djmike]

Does it look to be makeing a westward jog in the last couple frames on radar? Might be a wobble, or Im just staring at it too much, but can someone else confirm?