Quakertown needs snow Posted August 28, 2012 Share Posted August 28, 2012 looks better Link to comment Share on other sites More sharing options...
IsentropicLift Posted August 28, 2012 Share Posted August 28, 2012 The Northern and Western eyewalls are becoming very well defined now on New Orleans long range radar. It's hard to tell how organized the Southern and Eastern eyewalls are at this time due to the fact that the center is still a long way away from the radar site. On the most recent loop, you can see what appears to be a jog to the NNE unless I'm just tired and seeing things http://radar.weather.gov/radar.php?product=N0Z&rid=LIX&loop=yes Edit: Convection has now fired on the southern side of what appears to be a smaller, more well defined eye, the next 12 hours should be very interesting to say the least. It also looks like the jog that I saw to the NNE before was just part of a broader circulation. Link to comment Share on other sites More sharing options...
HSNN4 Posted August 28, 2012 Share Posted August 28, 2012 http://img18.imageshack.us/img18/5553/screenshot20120828at650.png Link to comment Share on other sites More sharing options...
OKpowdah Posted August 28, 2012 Share Posted August 28, 2012 Isaac officially has the lowest pressure of any pre-hurricane TC in the Atlantic Link to comment Share on other sites More sharing options...
Mike.Ventrice Posted August 28, 2012 Share Posted August 28, 2012 You can see the center of Isaac's circulation now from New Orleans' radar: Link to comment Share on other sites More sharing options...
turtlehurricane Posted August 28, 2012 Share Posted August 28, 2012 Isaac officially has the lowest pressure of any pre-hurricane TC in the Atlantic This has got to be a hurricane now, recon is finding hundreds of miles of hurricane force winds at flight level, with peak flight level winds up to 100 mph. SFMR isn't finding much hurricane force sfc winds but under convection there must be. Isaac now centered 80 miles from the tip of the delta and 165 miles from downtown New Orleans. Winds gusting over tropical storm force across eastern LA with winds sustained near 35 mph. 1.6 ft of surge on the south shore of Lake Pontchartrain, 3.4 ft of surge at Shell Beach, and 2.3 ft of surge at the tip of the delta (where winds are gusting over 60 mph). Link to comment Share on other sites More sharing options...
Wild Weather Monger Posted August 28, 2012 Share Posted August 28, 2012 Suppose Isaac is a good a proving ground as any for the lower salinity helps to intensify hurricanes studies. Interestingly, coastal buoys show little change in water temps in spite of a full night of in many cases sustained storm force winds. Link to comment Share on other sites More sharing options...
lakeeffectkid383 Posted August 28, 2012 Share Posted August 28, 2012 This has got to be a hurricane now, recon is finding hundreds of miles of hurricane force winds at flight level, with peak flight level winds up to 100 mph. SFMR isn't finding much hurricane force sfc winds but under convection there must be. Isaac now centered 80 miles from the tip of the delta and 165 miles from downtown New Orleans. Winds gusting over tropical storm force across eastern LA with winds sustained near 35 mph. 1.6 ft of surge on the south shore of Lake Pontchartrain, 3.4 ft of surge at Shell Beach, and 2.3 ft of surge at the tip of the delta (where winds are gusting over 60 mph). There was a 70kt surface wind found. Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted August 28, 2012 Share Posted August 28, 2012 impressive "tropical storm" http://www.votingrulez.com/file/uploads/SAT_GULH_VIS_ANI2.gif Link to comment Share on other sites More sharing options...
OKpowdah Posted August 28, 2012 Share Posted August 28, 2012 This has got to be a hurricane now, recon is finding hundreds of miles of hurricane force winds at flight level, with peak flight level winds up to 100 mph. SFMR isn't finding much hurricane force sfc winds but under convection there must be. Isaac now centered 80 miles from the tip of the delta and 165 miles from downtown New Orleans. Winds gusting over tropical storm force across eastern LA with winds sustained near 35 mph. 1.6 ft of surge on the south shore of Lake Pontchartrain, 3.4 ft of surge at Shell Beach, and 2.3 ft of surge at the tip of the delta (where winds are gusting over 60 mph). I meant re: the 7am advisory Link to comment Share on other sites More sharing options...
donsutherland1 Posted August 28, 2012 Share Posted August 28, 2012 This has got to be a hurricane now, recon is finding hundreds of miles of hurricane force winds at flight level, with peak flight level winds up to 100 mph. SFMR isn't finding much hurricane force sfc winds but under convection there must be. Isaac now centered 80 miles from the tip of the delta and 165 miles from downtown New Orleans. Winds gusting over tropical storm force across eastern LA with winds sustained near 35 mph. 1.6 ft of surge on the south shore of Lake Pontchartrain, 3.4 ft of surge at Shell Beach, and 2.3 ft of surge at the tip of the delta (where winds are gusting over 60 mph). NHC will almost certainly upgrade Isaac to a hurricane in its 10 am CDT advisory (probably 70 kts-75 kts given the gap between flight-level winds and SFMR). Link to comment Share on other sites More sharing options...
bluewave Posted August 28, 2012 Share Posted August 28, 2012 We may see the NHC move the projected track a few miles west from the recent radar trends. http://www.nhc.noaa.gov/archive/2012/graphics/al09/loop_5W.shtml Link to comment Share on other sites More sharing options...
Camille>Katrina Posted August 28, 2012 Share Posted August 28, 2012 What are thoughts that this guy does a right adjustment like alot of storms approaching land?Second do you guys remember Dennis years back that got locked into Mobile bay every little piece of land it just bounced off it till it made it to Mobile.Now I am not saying it goes to Mobile by far just wondering about frictional land interaction with with weak steering currents.I remember in Georges I was never so happy to see the eye come on top of me because I knew it would stall and peace would come that night Link to comment Share on other sites More sharing options...
turtlehurricane Posted August 28, 2012 Share Posted August 28, 2012 Flooding on the lakeshore of New Orleans, they show it occasionally here: http://www.fox8live.com/category/235642/watch-fox8live Considering the true water level of 4.8 ft at Shell Beach since we're near high tide, I believe everything east of the Mississippi that's not protected by a levee is underwater. Link to comment Share on other sites More sharing options...
mattmfm Posted August 28, 2012 Share Posted August 28, 2012 Pressure down to 975mb. Link to comment Share on other sites More sharing options...
friedmators Posted August 28, 2012 Share Posted August 28, 2012 Interesting movement on the HRRR 10m wind forecast. http://rapidrefresh.noaa.gov/hrrrconus15min/jsloop.cgi?dsKeys=hrrr_15min:&runTime=2012082812&plotName=wind15min_t610m&fcstInc=15&numFcsts=61&model=hrrr&ptitle=HRRR%20Model%20Fields&maxFcstLen=15&fcstStrLen=-1&resizePlot=1&domain=t6&wjet=1 Link to comment Share on other sites More sharing options...
phil882 Posted August 28, 2012 Share Posted August 28, 2012 There was a 70kt surface wind found. Latest recon obs actually are to the SW of the last fix. Its very interesting to see the HRRR now indicates a due west track for its entire short range prediction. While I think this is a little too far south, this suggests that the storm could stall while still over the ocean or very near the coastline of Louisiana. Lets see if the global models come in line at 12z. Link to comment Share on other sites More sharing options...
Solak Posted August 28, 2012 Share Posted August 28, 2012 #NOAA42 passing through center of #Isaac for the fifth and last time this mission. Storm underwent many changes in rain and wind structure. Link to comment Share on other sites More sharing options...
eurojosh Posted August 28, 2012 Share Posted August 28, 2012 Latest recon obs actually are to the SW of the last fix. Its very interesting to see the HRRR now indicates a due west track for its entire short range prediction. While I think this is a little too far south, this suggests that the storm could stall while still over the ocean or very near the coastline of Louisiana. Lets see if the global models come in line at 12z. The GFS has been suggesting a westward drift once Isaac came onshore for a couple of days now; the 12Z NAM suggests this westward drift actually occurs before it comes onshore somewhere just before the LA-TX border. I think the GFS could mimic this more southern drift. The question is whether keeping the center of circulation just offshore will maintain the strength of the storm longer than expected. The good news is, we're not talking about a highly populated coastal region. Link to comment Share on other sites More sharing options...
turtlehurricane Posted August 28, 2012 Share Posted August 28, 2012 Another shot of Lake Pontchartrain beginning to overflow it's banks. Local news strongly urging people to stay the fook away from the lake. Link to comment Share on other sites More sharing options...
donsutherland1 Posted August 28, 2012 Share Posted August 28, 2012 No upgrade at 11 am. Link to comment Share on other sites More sharing options...
lakeeffectkid383 Posted August 28, 2012 Share Posted August 28, 2012 Still a TS at 11. Link to comment Share on other sites More sharing options...
phil882 Posted August 28, 2012 Share Posted August 28, 2012 No upgrade at 11 am. I'm quite surprised... perhaps the dropsonde was erroneous. Just read the Stewart related discussion. There is no mention of the dropsonde observation. Either it is erroneous or he simply didn't get word of it in time. Link to comment Share on other sites More sharing options...
turtlehurricane Posted August 28, 2012 Share Posted August 28, 2012 Quite surprised.... Me too, dropsonde and FL winds easily support it, as well as winds sustained at 69 mph on an oil platform (~20 m above sea level) far away from the center. Since when did the SFMR become the final arbitrator of intensity? They often ignored it a few years ago. Link to comment Share on other sites More sharing options...
Ian Posted August 28, 2012 Share Posted August 28, 2012 You like them They've gotta have their reasons. Should hand it to them at least showing they are not pressured by outside sources to fib. Could always get a special advisory if needed. Link to comment Share on other sites More sharing options...
donsutherland1 Posted August 28, 2012 Share Posted August 28, 2012 From the NHC's discussion: THE MAXIMUM 850 MB FLIGHT-LEVEL WIND OBSERVED HAS BEEN 89 KT... WHICH EQUATES TO A SURFACE WIND OF ABOUT 71 KT. HOWEVER... BIAS-ADJUSTED SFMR SURFACE WINDS HAVE ONLY BEEN AROUND 60-62 KT... WHICH CORRELATES WELL WITH DROPSONDE BOUNDARY LAYER-DERIVED SURFACE WINDS. AS SUCH...THE INTENSITY OF ISAAC IS BEING MAINTAINED AT 60 KT...WHICH IS JUST BELOW HURRICANE STATUS. Link to comment Share on other sites More sharing options...
Clinch Leatherwood Posted August 28, 2012 Share Posted August 28, 2012 From the NHC's discussion: THE MAXIMUM 850 MB FLIGHT-LEVEL WIND OBSERVED HAS BEEN 89 KT... WHICH EQUATES TO A SURFACE WIND OF ABOUT 71 KT. HOWEVER... BIAS-ADJUSTED SFMR SURFACE WINDS HAVE ONLY BEEN AROUND 60-62 KT... WHICH CORRELATES WELL WITH DROPSONDE BOUNDARY LAYER-DERIVED SURFACE WINDS. AS SUCH...THE INTENSITY OF ISAAC IS BEING MAINTAINED AT 60 KT...WHICH IS JUST BELOW HURRICANE STATUS. http://www.ssd.noaa.gov/PS/TROP/floaters/09L/imagery/wv-animated.gif What's the half circle moving west away from the southwestern quadrant of the storm? Link to comment Share on other sites More sharing options...
HurricaneJosh Posted August 28, 2012 Share Posted August 28, 2012 The formula for converting flight-level winds to surface (10-m) winds isn't fixed. While the conversion factor tends to be around 90% in a healthy hurricane, that can vary: with rapidly decaying, high-latitude systems, it can be as low as 65%, whereas in a rapidly intensifying, deep-tropical cyclone, it can be near 100%. For whatever reason, Isaac is having trouble mixing the high winds to the surface. Very annoying storm. Link to comment Share on other sites More sharing options...
HurricaneTracker Posted August 28, 2012 Share Posted August 28, 2012 http://www.ssd.noaa....wv-animated.gif What's the half circle moving west away from the southwestern quadrant of the storm? It looks like some sort of MCV moving away as remnants of previously deep convection. Link to comment Share on other sites More sharing options...
PSUBlizzicane2007 Posted August 28, 2012 Share Posted August 28, 2012 The formula for converting flight-level winds to surface (10-m) winds isn't fixed. While the conversion factor tends to be around 90% in a healthy hurricane, that can vary: with rapidly decaying, high-latitude systems, it can be as low as 65%, whereas in a rapidly intensifying, deep-tropical cyclone, it can be near 100%. For whatever reason, Isaac is having trouble mixing the high winds to the surface. Very annoying storm. Despite that, though, there *was* a dropsonde with 65 KT winds at the surface. I guess that isn't enough. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.