ATL : TROPICAL DEPRESSION ALEX - MODELS

[Ptarmigan]

Quite frankly, I have very low confidence on any of the models for Alex. They are all over the place.

[KWT]

thats key KWT....as another SV moving into the pacific is going to move in after this high in the rockies...which I might add does not look to be all that...

Indeed, I think the ULH is about what the ECM was expecting right now, but its not a large anticyclone right now and is going to need to merge with the Upper high in the Atlantic. Just something to keep an ye would be an unexpected new ULL form on the SE side of the upper high, they do like to form there, sometimes unexpected. I'd hope that wouldn't happen given al lthe models don't show anything but ya never can be certain.

[tolakram]

Looks like the models that predicted, in the short term, that Alex would move almost due north are verifying. GFDL and HWRF for sure, maybe the globals but the resolution is too low for me to see.

[Dean4Storms]

I'm sticking by the Extrapolation model, it may not have gotten the intensity down as well as the other models but it nailed the landfall much closer than all the rest!!!!

[Air Force Met]

In a way, this is a good thing - a reminder that we need to critically evaluate all of the models, and swing from none. This includes taking a deeper look at the mass fields and not just a storm track.

I could not agree more. That is the main reason I have been doing micro-analysis of the constant pressure maps. I have been comparing the maps from 00z to 00z and 12z to 12z...analyzing 24 hour height falls and hand analyzing the height fields at 10 mtr increments. I then go back and compare the 24 hr forecasts of the previous runs and try to get a handle on who is doing what.

In this game...those little details make a big difference sometimes. People get hung up on the exact dot that a model is putting a storm and fail to remember to look at the steering a model is suggesting.

[KWT]

Looks like the models that predicted, in the short term, that Alex would move almost due north are verifying. GFDL and HWRF for sure, maybe the globals but the resolution is too low for me to see.

Thus far it does look like they aren't doing too bad...but ultimatly over the longer term all it does is put back landfall IMO by however many hours...of course also gives the system more time to strengthen over water, wonder whether thats why the 18z HWRF was stronge then its quicker 12z run, must be...

[cycloneye]

To add more fuel to the model debate,the BAMS tonight go more north.

945
WHXX01 KWBC 290046
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0046 UTC TUE JUN 29 2010

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

TROPICAL CYCLONE ALEX (AL012010) 20100629 0000 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
100629 0000 100629 1200 100630 0000 100630 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 20.7N 91.6W 22.1N 92.3W 23.6N 93.1W 24.9N 94.0W
BAMD 20.7N 91.6W 21.7N 92.2W 22.8N 93.1W 23.9N 94.2W
BAMM 20.7N 91.6W 22.0N 92.2W 23.4N 93.1W 24.7N 94.0W
LBAR 20.7N 91.6W 21.9N 92.3W 23.7N 93.6W 25.5N 94.8W
SHIP 50KTS 56KTS 65KTS 73KTS
DSHP 50KTS 56KTS 65KTS 73KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
100701 0000 100702 0000 100703 0000 100704 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 26.1N 94.8W 27.8N 97.2W 29.4N 99.5W 31.7N 99.3W
BAMD 25.1N 95.2W 27.1N 96.9W 29.8N 98.6W 33.6N 98.6W
BAMM 26.0N 94.9W 28.2N 97.0W 30.4N 99.2W 33.3N 99.4W
LBAR 27.1N 95.7W 30.2N 96.1W 31.9N 95.3W 32.6N 94.2W
SHIP 79KTS 86KTS 79KTS 64KTS
DSHP 79KTS 37KTS 28KTS 27KTS

...INITIAL CONDITIONS...
LATCUR = 20.7N LONCUR = 91.6W DIRCUR = 0DEG SPDCUR = 4KT
LATM12 = 20.1N LONM12 = 91.6W DIRM12 = 341DEG SPDM12 = 4KT
LATM24 = 19.2N LONM24 = 91.1W
WNDCUR = 50KT RMAXWD = 20NM WNDM12 = 50KT
CENPRS = 987MB OUTPRS = 1006MB OUTRAD = 250NM SDEPTH = D
RD34NE = 60NM RD34SE = 30NM RD34SW = 30NM RD34NW = 50NM

[ROCK]

experimental GFDL given to Jeff Masters showed an area between CC and Galveston..that was earlier this morning though..FWIW...

.....HWRF shifted north...0z models going to be VERY interesting...

[cycloneye]

A reminder that the 00z models will have the imput from the Gulfstream jet.

[Flyinman]

Wow, according to most of the latest models, no matter where Alex makes landfall looks like most of Texas will experience heavy rain. I hope this will not end up similar to Allison.

[HouTXmetro]

Sorry, but the BAM Suite from run to run is all over the place...IT was mid TX coast this morning then deep Northern Mexico this afternoon. Now back to TX coast? what a joke of a model. lol

[ROCK]

the key here is WHY do they bend back north....maybe its because the high coming down is not as potent as once thought, weaken ALT ridging by another SV in the PAC-NW...just some food for thought....if the 0z shift north tonight I am going puke....

[Wx_Warrior]

BAMM has been all over the place. Pick a spot any spot.

I hope the 0z models have the g4 data...if not, for sure tomorrow.

[HouTXmetro]

the key here is WHY do they bend back north....maybe its because the high coming down is not as potent as once thought, weaken ALT ridging by another SV in the PAC-NW...just some food for thought....if the 0z shift north tonight I am going puke....

Don't the models traditionally shift left during the day and right at night?

[ROCK]

Sorry, but the BAM Suite from run to run is all over the place...IT was mid TX coast this morning then deep Northern Mexico this afternoon. Now back to TX coast? what a joke of a model. lol

you dont look at the BAMMS for track...Metro......what we are looking at are hints for the next run of the models. HWRF moved north, NAM moved north along the coast, GFS moved north and along the coast......why?

[ROCK]

the key here is WHY do they bend back north....maybe its because the high coming down is not as potent as once thought, weaken ALT ridging by another SV in the PAC-NW...just some food for thought....if the 0z shift north tonight I am going puke....

Don't the models traditionally shift left during the day and right at night?

traditionally? I didnt know models had traditions....

[HouTXmetro]

Sorry, but the BAM Suite from run to run is all over the place...IT was mid TX coast this morning then deep Northern Mexico this afternoon. Now back to TX coast? what a joke of a model. lol

you dont look at the BAMMS for track...Metro......what we are looking at are hints for the next run of the models. HWRF moved north, NAM moved north along the coast, GFS moved north and along the coast......why?

Point taken Rock, see my previous post about model shifts throughout the day and night..just an observation. LOL and you know what I was trying to say about the models!

[jasons2k]

In a way, this is a good thing - a reminder that we need to critically evaluate all of the models, and swing from none. This includes taking a deeper look at the mass fields and not just a storm track.

I could not agree more. That is the main reason I have been doing micro-analysis of the constant pressure maps. I have been comparing the maps from 00z to 00z and 12z to 12z...analyzing 24 hour height falls and hand analyzing the height fields at 10 mtr increments. I then go back and compare the 24 hr forecasts of the previous runs and try to get a handle on who is doing what.

In this game...those little details make a big difference sometimes. People get hung up on the exact dot that a model is putting a storm and fail to remember to look at the steering a model is suggesting.

Excellent points to remember.

The analogy I like to use is back when we were in grade school learning grammar, we were asked to put our fingers over part of a sentence to determine if a word was a proposition or if the sentence was a compound sentence, etc.

Sometimes the best way to figure out where a hurricane may go is to hide it, forget it's there, and just focus on the map. Focus on the meteorology itself and don't get distracted by model runs of potential paths. Look at the pattern, the height fields, etc. Get that nailed down and then add the hurricane to the mix and figure out where it should go based on what you see. Or something like that...

[vaffie]

The Bam's are not even dynamic models at all. There is not even any point looking at them usually. They simply take the GFS initial data and extrapolate what would happen if absolutely nothing in the tropics changed for the next 120 hours. They have no idea if a cold front is coming or a high is building. They simply show where the wind is blowing right now...

[lonelymike]

I'm sticking by the Extrapolation model, it may not have gotten the intensity down as well as the other models but it nailed the landfall much closer than all the rest!!!!

No statistical analysis shows it was the LBAR that was most accurate