Mencken_Fan Posted August 21, 2011 Share Posted August 21, 2011 First thoughts on Irene: I believe the STR will verify just a tad stronger in the early going, providing a slight southward track vs. NHC. Otherwise, no real deviation from NHC's thinking from that point other than Irene will have a little more lattitude to gain longitude as it heads into the Florida Straits. This track also would reduce the land interaction with Haiti, and somewhat regarding Cuba. Thus, a slightly stronger 'cane than the NHC is depicting south of Haiti. Boy am I surprised to see that.... Based solely on models your scenario is perfectly plausible; but how can you so disregard the real-time convective explosion north of the LLC, especially when we're just entering the overnight phase of the diurnal effect? Based on this year's history so far, the current convective explosion will turn out to be nothing....but it's late August now, so that's no longer bankable. It's time to turn off the auto-pilot. Link to comment Share on other sites More sharing options...
DoctorMu Posted August 21, 2011 Share Posted August 21, 2011 The wave came off Africa as almost a dumbbell of 2 parts, one NW and the other SE with the center somewhere in between. Central convection began to blow up just NW of the center today, and its expansion has been primarily to the N and W. There is less development in the SE quadrant...and the system overall appears en masse to be moving W or WNW. Further development and filling in that SE quadrant overnight and into tomorrow should be interesting Link to comment Share on other sites More sharing options...
Jaguars Posted August 21, 2011 Share Posted August 21, 2011 Does a fla east coast solution seem all but eliminated at this time? Seems like the median modeled track woild have it on a beeline towards key west Link to comment Share on other sites More sharing options...
PSUBlizzicane2007 Posted August 21, 2011 Share Posted August 21, 2011 Piss poor job by NHC and borderline irresponsible that they initiated Irene as far south as 14.9 north.. and moving due west. It is quite clear by the satellite images that the center of circulation is a good 2 or 3 degrees north of this fix and this thing is heading WNW toward the virgin islands. And if you look at the hurricane hunter track... they didnt hit TS force winds until the northern extent of its flight path. Look for a new/ corrected fix much further north after the next flight. does anyone else see what I am talking about? So going by what reconnaissance observed over sketchy satellite interpretations is piss poor and irresponsible? I'm going to suggest that you read and learn more before posting such an inflammatory accusation. Link to comment Share on other sites More sharing options...
hm8 Posted August 21, 2011 Share Posted August 21, 2011 FWIW the NHC strength forecast is pretty much below what all the models are showing. Then again, I'm not sure how the models do with land interaction, which Irene might end up having a lot of... Link to comment Share on other sites More sharing options...
janetjanet998 Posted August 21, 2011 Share Posted August 21, 2011 center looks to be 15.5N 59.5W per shortwave right near the forecast track thats on the SW wide of the big blob but convection seems to be wrapping around the NW side now too last 1hr so convection has moved over the "NHC center" and is now wrapping around the north and into the NW Quad edit: red dot a couple of tenths too far north Link to comment Share on other sites More sharing options...
LakeEffectKing Posted August 21, 2011 Share Posted August 21, 2011 Like LEK's map...I've been hollering for Mobile since Thurs or Fri. But I might be more apt to lean east side of Mobile-Pensacola right now...and I wouldn't rule out a Big Bend type hit or inland on the West Coast. Concerns I have are the models continuing to think this thing is just going to cruise through the Caribbean and over land masses and hold its own. NHC did right to go low end for the most part. Bigger concern I have is what the models do as this lifts north and north-northeast...slowing it down. The ensembles have been hitting on this since midweek, and I am concerned that this may wait a day or two before accelerating (apologies if this has been touched on...haven't gone back over the thread). This has some potential to be a major flooding event for someone between MS and GA/FL. And I think that may be worth watching. Lots of potential with this one...obviously being in JAX, I'm watching this closely...as a Big Bend hit would be a major deal here, potentially moreso than an up the east coast of FL hit. Hey Matt! Boy, you seem to be traveling all over! Hope all is well. I concur with your thoughts on the ensembles. I'm not really confident of the mid latitude features by the time this gets near Cuba. Getting a storm (which should be fairly large) to turn back more west, once it has already changed to the north seems intuitively more difficult. IMO, to get to Mobile or further west, Irene would have to track south of Jamaica....barring any radically large changes in the mid latitude by then, as depicted by model consensus. Link to comment Share on other sites More sharing options...
DopplerWx Posted August 21, 2011 Share Posted August 21, 2011 Will the 00z gfs have the recon data ingested? Link to comment Share on other sites More sharing options...
Mallow Posted August 21, 2011 Share Posted August 21, 2011 last 1hr so convection has moved over the "NHC center" and is now wrapping around the north and into the NW Quad Nah, not quite. The NHC position is 14.9N, so still south of the convection. Link to comment Share on other sites More sharing options...
janetjanet998 Posted August 21, 2011 Share Posted August 21, 2011 Nah, not quite. The NHC position is 14.9N, so still south of the convection. That was several hours ago here is another shot....15.3 59.5ish Link to comment Share on other sites More sharing options...
Ed Lizard Posted August 21, 2011 Author Share Posted August 21, 2011 PDIII- Seriously good way to learn besides reading here and seeing what the professionals say, is reading NHC forecast discussions. You'll notice many organizing systems will have centers displaced from the center of the deepest convection. Even with microwave and other things besides cloud top temps, they'll often reposition based on recon data or visible imagery. Organizing systems will sometimes have stretched low level centers, satellite circulations around a mean, or displaced mid and low level centers. The center may reform further North with time, or not, but the NHC had aircraft data to work off of. You might also check vortex data messages, available at the NHC website to see where and when the center was fixed by aircraft. Link to comment Share on other sites More sharing options...
WeatherMimmi Posted August 21, 2011 Share Posted August 21, 2011 FWIW the NHC strength forecast is pretty much below what all the models are showing. Then again, I'm not sure how the models do with land interaction, which Irene might end up having a lot of... Wow!! This post really makes a of GOM Monster possible. Thank you to all the folks who help predict weather conditions and these forcast runs, it really helps the rest of us prepare our homes and families and learn about this type weather event before hand. Link to comment Share on other sites More sharing options...
phil882 Posted August 21, 2011 Share Posted August 21, 2011 The number one rule of tracking storms, especially in their formative stages, is to never think you know where the LLC is based on satellite. Surface centers are notoriously tricky to pick out on satellite when the storm is still not that organized. Recon found the center around where the NHC placed it. Satellite suggests the mid-level circulation center is further north, yes, and that may have an impact down the line causing the LLC to be pulled or reform closer to the convection. But that doesn't mean the NHC was wrong to place the center where they placed it. I do agree that the overall system (MLC or what have you) seems to be heading WNW rather than W, but that is also hard to say for sure. Strongly agree with Mallow here... the center that recon found was very broad and diffuse, so lots of center relocations could occur... most recent microwave pass suggests the center is south of the convection and still not very well defined. I'm working on a forecast map and I'll have that out shortly. Link to comment Share on other sites More sharing options...
Srain Posted August 21, 2011 Share Posted August 21, 2011 That was several hours ago Again as we have seen several times this season, IR imagery can be very deceiving and does not reflect surface circulation/LLC like HI RES Visible imagery. Link to comment Share on other sites More sharing options...
Mallow Posted August 21, 2011 Share Posted August 21, 2011 That was several hours ago here is another shot....15.3 59.5ish Correct, but you almost have it moving NW. You can't really call that the "NHC" position if you're just guesstimating the current center. I'm not saying your center position is wrong, but it's certainly not an extrapolation of the NHC position. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted August 21, 2011 Share Posted August 21, 2011 Strongly agree with Mallow here... the center that recon found was very broad and diffuse, so lots of center relocations could occur... most recent microwave pass suggests the center is south of the convection and still not very well defined. I'm working on a forecast map and I'll have that out shortly. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING THE TROPICAL WAVE EAST OF THE LESSER ANTILLES FOUND A SMALL LOW-LEVEL CIRCULATION CENTER JUST SOUTHWEST OF A LARGE CONVECTIVE BURST AND A MINIMUM PRESSURE OF ABOUT 1006 MB. Link to comment Share on other sites More sharing options...
phil882 Posted August 21, 2011 Share Posted August 21, 2011 Here is what I got... not confident at all, and I think major thing that can go wrong with this forecast is Hispaniola. I have it only grazing the coast but I'm not very confident that happens since Hispaniola has a tendency to attract tropical cyclones since the frictional torque becomes less to the north of the storm since the surface winds are lower over land. This effect gets stronger the more intense a tropical cyclone is, so if Irene gets even stronger than forecast here than things might need to be revised northward in the next forecast track along with further reduction in intensity. Even if this occurs though, I think the ridging will trends slightly stronger in the modeling over the next 24 hours, causing Irene to take a track further west the the model consensus beyond 72 hours. Link to comment Share on other sites More sharing options...
phil882 Posted August 21, 2011 Share Posted August 21, 2011 AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING THE TROPICAL WAVE EAST OF THE LESSER ANTILLES FOUND A SMALL LOW-LEVEL CIRCULATION CENTER JUST SOUTHWEST OF A LARGE CONVECTIVE BURST AND A MINIMUM PRESSURE OF ABOUT 1006 MB. The planetary circulation was very small in size at the time... but the storm relative circulation is far larger. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted August 21, 2011 Share Posted August 21, 2011 Does a fla east coast solution seem all but eliminated at this time? Seems like the median modeled track woild have it on a beeline towards key west No - buuut at some point one should concede to the guidance unless they have a darn good reason to go against. Link to comment Share on other sites More sharing options...
janetjanet998 Posted August 21, 2011 Share Posted August 21, 2011 ...Irene approaching the Leeward Islands... summary of 1100 PM AST...0300 UTC...information-----------------------------------------------location...15.3n 59.9w about 95 mi...150 km E of Dominicaabout 120 mi...195 km se of Guadeloupe maximum sustained winds...50 mph...85 km/hpresent movement...W or 280 degrees at 22 mph...35 km/h minimum central pressure...1006 mb...29.71 inches Link to comment Share on other sites More sharing options...
LakeEffectKing Posted August 21, 2011 Share Posted August 21, 2011 AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING THE TROPICAL WAVE EAST OF THE LESSER ANTILLES FOUND A SMALL LOW-LEVEL CIRCULATION CENTER JUST SOUTHWEST OF A LARGE CONVECTIVE BURST AND A MINIMUM PRESSURE OF ABOUT 1006 MB. John, I think that was your LL swirl that we talked about early...it appears to have slid to the northwest a bit to close the gap with the main ML convective complex. This seemingly took/is taking place with in a general cyclonic signature at multiple levels, all preparing for alignment.... Link to comment Share on other sites More sharing options...
Typhoon Tip Posted August 21, 2011 Share Posted August 21, 2011 The planetary circulation was very small in size at the time... but the storm relative circulation is far larger. Perhaps, but "small circulation" and "diffused" are anti-corollary terms. I think I get what you meant though - even though there is was a small circulation identified, it exists inside a much larger cyclonic circulation. THAT I completely agree with! In fact, I noticed that a ring of convection propagated away from the overall axis, and as it did - and I believe "scoured" SAL away - we immediately saw a TC response in the core. Fascinating really .... The rest going forward - I think there is some possibility that this ends up S of Cuba. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted August 21, 2011 Share Posted August 21, 2011 John, I think that was your LL swirl that we talked about early...it appears to have slid to the northwest a bit to close the gap with the main ML convective complex. This seemingly took/is taking place with in a general cyclonic signature at multiple levels, all preparing for alignment.... I was wanting to respond to you! yes, I think so - and to your earlier point this afternoon, the persistence of both will tend to draw them together. This really is a class room system folks. Good stuff! Link to comment Share on other sites More sharing options...
Amped Posted August 21, 2011 Share Posted August 21, 2011 As the pressure falls the center will become better defind. Still has another 24-36 hrs to go, be patient. Also there is no garentee the center is under the deep convection or aligned with the mid level center at this point. Link to comment Share on other sites More sharing options...
LakeEffectKing Posted August 21, 2011 Share Posted August 21, 2011 No - buuut at some point one should concede to the guidance unless they have a darn good reason to go against. Unless you have a 965mb stemwinder progged 200 miles off the BM in Jan. But, your point is well taken...whether the ensemble means were consistently west due to lower resolution or not, is a valid debate. However, with both sets (GFS and Euro) having so many members to the west, along with UK and GGEM sticking there noses up at their big brothers, is cause for pause, regarding the normal battle between the op GFS and Euro. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted August 21, 2011 Share Posted August 21, 2011 E-gads! I just saw the 18z GFDL's nearing Cat 5 near the western tip of Cuba - wow. This is like watching a cheesy movie where the next scene is predictable - please tell me this isn't headed for melo drama center. Link to comment Share on other sites More sharing options...
janetjanet998 Posted August 21, 2011 Share Posted August 21, 2011 ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM IRENE DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011 1100 PM AST SAT AUG 20 2011 SATELLITE IMAGES INDICATE THAT IRENE IS MAINTAINING A LARGE AREA OF CURVED CONVECTIVE BANDING ON THE NORTHERN SIDE OF THE SURFACE CIRCULATION. THE GUADELOUPE RADAR CONTINUES TO SHOW THIS BANDING ALONG WITH A DISTINCT MID-LEVEL VORTEX...WHICH IS ALSO VISIBLE IN MICROWAVE IMAGERY. THE INITIAL WIND SPEED IS KEPT AT 45 KT AND THE NEXT RECONNAISSANCE AIRCRAFT IS SCHEDULED TO FLY THROUGH IRENE AROUND 1200 UTC. THE INITIAL MOTION ESTIMATE IS ABOUT 280/19. A MID-LEVEL RIDGE OVER THE WESTERN ATLANTIC OCEAN IS EXPECTED TO SLOWLY WEAKEN OVER THE NEXT COUPLE OF DAYS. THIS PATTERN SHOULD STEER IRENE TOWARD THE WEST-NORTHWEST WITH A GRADUAL DECELERATION. AFTER THAT TIME...A MID-LATITUDE TROUGH MOVING OFFSHORE OF THE SOUTHEASTERN UNITED STATES SHOULD CAUSE A WEAKNESS IN THE SUBTROPICAL RIDGE. HOW MUCH OF A WEAKNESS IS STILL UP FOR DEBATE...HOWEVER...WITH A VARIETY OF MODEL SOLUTIONS SHOWING LARGE TRACK SPREAD AT THE END OF THE FORECAST PERIOD. IN ADDITION...A FEW OF THE MODELS...SUCH AS THE UKMET...SHOW MORE OF AN EMPHASIS ON A SECOND TROUGH MOVING INTO THE SOUTHERN UNITED STATES AND DO NOT SHOW THE FIRST TROUGH AFFECTING IRENE MUCH. THE GUIDANCE HAS SHIFTED SOMEWHAT TO THE WEST IN THE LATER PERIODS...AND IT SEEMS REASONABLE TO SHIFT THE NHC FORECAST IN THAT DIRECTION. GIVEN THE LARGE SPREAD IN THE GUIDANCE...THIS IS A GOOD TIME TO REMIND USERS THAT THE AVERAGE DAY 4 AND 5 NHC TRACK FORECAST ERRORS ARE 200 TO 250 MILES. WITH THE IMPROVED STRUCTURE ON MICROWAVE...STRENGTHENING IS LIKELY AS THE STORM TRAVERSES VERY WARM WATERS WITH LIGHT SHEAR CONDITIONS. ALMOST ALL OF THE GUIDANCE SHOWS IRENE BECOMING A HURRICANE IN A DAY OR TWO...AND THE NHC FORECAST HAS BEEN INCREASED DURING THE FIRST 48 HOURS. AFTER THAT TIME THE INTENSITY FORECAST IS HIGHLY DEPENDENT ON HOW MUCH LAND INTERACTION OCCURS WITH HISPANIOLA AND CUBA. THE CURRENT TRACK TAKES THE SYSTEM OVER THE SPINE OF CUBA BETWEEN 72 AND 96 HOURS...SO LITTLE INTENSIFICATION IS EXPECTED DURING THAT TIME...WITH SOME STRENGTHENING EXPECTED NEAR THE END OF THE PERIOD AFTER IRENE MOVES AWAY FROM LAND. IT IS WORTH NOTING THAT THE MODELS THAT SHOW LESS LAND INTERACTION...SUCH AS THE GFDL OR HWRF...HAVE IRENE BECOMING A MAJOR HURRICANE...AND THAT IS NOT OUT OF THE QUESTION ESPECIALLY IF THE STORM MOVES ON THE FAR LEFT OR RIGHT SIDE OF THE FORECAST CONE AND AVOIDS SIGNIFICANT LAND INTERACTION. OVERALL...GIVEN THE TRACK FORECAST UNCERTAINTY AND THE POTENTIAL FOR LAND INTERACTION...THE INTENSITY FORECAST LATE IN THE PERIOD IS EVEN MORE UNCERTAIN THAN USUAL. A HURRICANE WATCH COULD BE REQUIRED FOR PUERTO RICO TOMORROW IF THERE IS A SIGNIFICANT NORTHWARD ADJUSTMENT TO THE TRACK FORECAST. OF NOTE...THIS IS THE THIRD EARLIEST TO HAVE NINE NAMED STORMS FORM IN THE ATLANTIC BASIN...BEHIND 2005 AND 1936. FORECAST POSITIONS AND MAX WINDS INIT 21/0300Z 15.3N 59.9W 45 KT 50 MPH 12H 21/1200Z 16.0N 62.7W 50 KT 60 MPH 24H 22/0000Z 16.6N 65.9W 55 KT 65 MPH 36H 22/1200Z 17.2N 68.4W 65 KT 75 MPH 48H 23/0000Z 18.0N 70.7W 75 KT 85 MPH 72H 24/0000Z 19.5N 75.0W 50 KT 60 MPH 96H 25/0000Z 21.5N 78.0W 50 KT 60 MPH...INLAND 120H 26/0000Z 24.5N 80.5W 60 KT 70 MPH...OVER WATER Link to comment Share on other sites More sharing options...
Typhoon Tip Posted August 21, 2011 Share Posted August 21, 2011 Unless you have a 965mb stemwinder progged 200 miles off the BM in Jan. But, your point is well taken...whether the ensemble means were consistently west due to lower resolution or not, is a valid debate. However, with both sets (GFS and Euro) having so many members to the west, along with UK and GGEM sticking there noses up at their big brothers, is cause for pause, regarding the normal battle between the op GFS and Euro. HAHAHA - so true. oh man. August is such a weird month. I mean ...it's thick of summer out there but in so little time it's a completely different world. Actually, I'm not seeing really much to unusual about this kind of spread in the guidance for D5+ I will be honest though and say that I do see some synoptic reason supporting the western cluster. We'll see. Link to comment Share on other sites More sharing options...
LakeEffectKing Posted August 21, 2011 Share Posted August 21, 2011 IR imagery is indeed often deceiving; and as you note, it's happened many times this season. But we're now in the core season watching in real-time a Mt. Vesuvius-like convective eruption.....yet some cant let go of their NHC-declared LLC because the NHC is their god. Will the north-side convection continue to increase overnight? Maybe yes; maybe no. But until we see with our own eyes....it's crazy to assume knowledge of where the center will be a few hours from now...or what tomorrow's model tracks will look like. I'd like to believe most here have at least several years of tropics watching but at times I have to wonder.... While you've been pulling your hair out watching IR loops, try the MW imagery, and also note that the SAME ML feature last night had pretty good convection....yet no SLP response. Now, we have essentially advected a small LL feature (and it's associated LL vorticity envelope) which makes it that much more difficult for a "not-so-seperate" ML convective blob to steal the necessary inflow to develop such a feature, being that it is in close proximity to the aforementioned (NHC investigated) LLC. Link to comment Share on other sites More sharing options...
PSUBlizzicane2007 Posted August 21, 2011 Share Posted August 21, 2011 IR imagery is indeed often deceiving; and as you note, it's happened many times this season. But we're now in the core season watching in real-time a Mt. Vesuvius-like convective eruption.....yet some cant let go of their NHC-declared LLC because the NHC is their god. Will the north-side convection continue to increase overnight? Maybe yes; maybe no. But until we see with our own eyes....it's crazy to assume knowledge of where the center will be a few hours from now...or what tomorrow's model tracks will look like. I'd like to believe most here have at least several years of tropics watching but at times I have to wonder.... You really need to rein in your posting if you are just going to be blatantly ignorant towards respected professionals and computer models. Link to comment Share on other sites More sharing options...
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