Just model discussion for TD5

[Vortex]

The latest 00z Nam rolling in is on board and resembling more the GFDL,GFS, and to some extent the dynamical models. Its becoming a little more clear and now consistently advertised by several of the "big guns" in the world of weather models that this system may be significantly impacted by a weakness/troughiness to the north and west over Florida and a ULL over the western carribean. The forecasted synoptic environment to the North and NW of the storm as well as developments in the western carribean may induce a more NW movement and potentially pose a threat to the Greater antilles, Cuba, Florida. As usual the devil is in the details.


Nam 8/25 00z:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... el_l.shtml

[Vortex]

Here is the Loop...sorry.


http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

[btangy]

I'm not sure I trust the NAM/WRF solution. The NAM/WRF obviously has problems with too much convection right after its initialization over the tropical oceans and also likes to spin up lots of robust vortices, several of which develop along this stalled frontal boundary to the N and act to draw TD5 north into the corresponding weakness in the ridge. I think this is a pretty extreme scenario and am inclined to discount it.

[ROCK]

I'm not sure I trust the NAM/WRF solution. The NAM/WRF obviously has problems with too much convection right after its initialization over the tropical oceans and also likes to spin up lots of robust vortices, several of which develop along this stalled frontal boundary to the N and act to draw TD5 north into the corresponding weakness in the ridge. I think this is a pretty extreme scenario and am inclined to discount it.

yep, The NAM is not really a tropical model but it is interesting to see what its spitting out now and again.

[ericinmia]

I'm not sure I trust the NAM/WRF solution. The NAM/WRF obviously has problems with too much convection right after its initialization over the tropical oceans and also likes to spin up lots of robust vortices, several of which develop along this stalled frontal boundary to the N and act to draw TD5 north into the corresponding weakness in the ridge. I think this is a pretty extreme scenario and am inclined to discount it.

yep, The NAM is not really a tropical model but it is interesting to see what its spitting out now and again.

If i remember right, the WRF was supposed to be able to handle the tropics. This years (NAM) isn't the same as the Eta-Nam of yesteryears

[tropicsgal05]

Which is the best model to look at right now?

[sevenleft]

While we're at it, lets have individual threads dedicated to satellite imagery, radar, surface observations, water temperatures, shear, steering currents, heat content, and upper air conditions....

[Vortex]

I'm not looking at this model from an intensity or tracking perspective per se but more the overall synoptic environment forecasted in comparison to the more respected global models(GFS) and the GFDL. Like the GFS and Gfdl the weakness to the north appears to be induced by a series of troughs each eroding the ridging to the north over and east of Florida. I point this out because this could have major implications in terms of landfalls and intensity. I noticed this scenario was pointed out in the 11pm discussion. I think many on the board are assuming the ridge will hold strong to the North and carry this system w/wnw throught the channel and into the Gulf. Will this happen? Possible. However, before this system ever gets to the western carribean we will know the impact of the weakness to the north. If the ridge is eroded enough it will have a more poleward movement and would likely affect Haiti, Cuba, and possibly florida before it ever made it into the gulf. Either way I feel very strongly it will make to the GOM just not sure how it will arrive there yet...

[btangy]

If i remember right, the WRF was supposed to be able to handle the tropics. This years (NAM) isn't the same as the Eta-Nam of yesteryears

No model out there right now that's in wide operational use can handle the tropics well. Handling the tropics requires a grasp of moist convection, which is arguably the where some of the weakest understanding lies in atmospheric science currently (vs. the well established understanding of the large-scale patterns and flows in the mid-latitudes).

With regards to the WRF, there are different versions of it out there. The one on NCEP's site is the NMM vesion (Nonhydrostatic Mesoscale Model). There is also the ARW version run at NCAR (Advanced Research WRF). From what limited runs I've seen of both, I like the ARW over the tropics better. Also, the Hurricane WRF will replace the GFDL model next season I believe. I'm sure this will all lead to much confusion.

[southerngale]

While we're at it, lets have individual threads dedicated to satellite imagery, radar, surface observations, water temperatures, shear, steering currents, heat content, and upper air conditions....

I agree. People just need to stop making ONE "official" thread for everything regarding TD5 or whatever system, and we can. Just start a thread about something when you have something relevant to start a thread about.

I don't like having one giant thread for everything. I think you start one about something particular regarding TD5 for example and then you can read about what you want. You can then click on the thread that pertains to the information you're seeking.

Just start a thread as we see fit...and it will all fall into place.

It seems so much better to me...I dunno.