ATL : TROPICAL DEPRESSION ALEX - MODELS

[tolakram]

It looks like the ECMWF and GFS are now both showing a wave that heads west through the Yucatan and into the BOC. The ECMWF develops a weak TS in the BOC and pushes it into Mexico. The GFS just pushes the wave into Mexico. At this point I like the consistency I am seeing with the global models and the solution from these models has been the one I have gone with for 93L since the beginning.

Looking through the posts, I am not sure why so many put down the GFS when it appears the ECMWF has not veered towards the GFS solution?

The GFS still hasn't seen Darby other than a weak blob of low pressure. That's pretty inexcusable. If the GFS is correct in this case I see it nothing more than a happy accident.

[gatorcane]

Right but the fact it doesn't see Darby really means nothing as far as 93L is concerned. I am pretty certain it is not a fluke

[tolakram]

Right but the fact it doesn't see Darby really means nothing as far as 93L is concerned. I am pretty certain it is not a fluke

Not seeing a storm indicates some serious issues in my opinion. Perhaps the upgrade preparations broke something, or perhaps it's having issues with a particular setup. Both areas are near the same latitude, both are in areas of similar pressure, and both are shown vaguely as amorphous blobs of lower pressure. I think this is enough to demonstrate some sort of issue with GFS since none of the other models are having issues identifying an existing storm.

This doesn't mean 93L will develop, it means nothing as far as 93L is concerned.

[cycloneye]

12 UTC BAMS

WHXX01 KWBC 241303
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1303 UTC THU JUN 24 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

DISTURBANCE INVEST (AL932010) 20100624 1200 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
100624 1200 100625 0000 100625 1200 100626 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 16.5N 79.6W 17.1N 81.4W 17.7N 83.0W 18.6N 84.5W
BAMD 16.5N 79.6W 16.5N 81.1W 16.5N 82.6W 16.7N 84.3W
BAMM 16.5N 79.6W 16.7N 81.2W 17.0N 82.7W 17.5N 84.2W
LBAR 16.5N 79.6W 16.9N 81.4W 17.7N 83.5W 18.8N 85.8W
SHIP 25KTS 29KTS 36KTS 45KTS
DSHP 25KTS 29KTS 36KTS 45KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
100626 1200 100627 1200 100628 1200 100629 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 19.5N 86.1W 21.7N 89.0W 23.8N 91.2W 24.8N 93.1W
BAMD 16.9N 86.1W 17.4N 89.4W 17.8N 92.3W 17.6N 95.5W
BAMM 17.9N 85.8W 19.2N 88.9W 20.5N 91.4W 21.0N 93.9W
LBAR 20.0N 88.0W 22.6N 91.5W 25.6N 93.1W 28.1N 94.1W
SHIP 54KTS 70KTS 80KTS 84KTS
DSHP 54KTS 41KTS 37KTS 40KTS

...INITIAL CONDITIONS...
LATCUR = 16.5N LONCUR = 79.6W DIRCUR = 285DEG SPDCUR = 8KT
LATM12 = 16.2N LONM12 = 78.2W DIRM12 = 281DEG SPDM12 = 5KT
LATM24 = 15.9N LONM24 = 76.8W
WNDCUR = 25KT RMAXWD = 75NM WNDM12 = 25KT
CENPRS = 1008MB OUTPRS = 1011MB OUTRAD = 180NM SDEPTH = S
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

$$

[KWT]

Will be interesting to see whether Wxman57 predicition of the models relocating quite a bit to the east will occur today because he thinks most of the models are actually picking up the wave behind it.

I think those GFDL/HWRF forecasts are going to bust rather badly in the not too distant future.

[littlevince]

The GFS still hasn't seen Darby other than a weak blob of low pressure. That's pretty inexcusable .

About Darby, GFS doesn't seem all that different from ECMWF

[KWT]

If you take a look at the size of the core of Darby, you can see why the two models aren't that strong, simply because they can't model the system well enough due to the resolution limitations.

[N2Storms]

so the spread now is anywhere from mexico to new orleans it appears...
that sure is a big spread

Mexico to Florida! Crazy.

Yep, Euro is furthest south with Mexico...HWRF furthers east around Destin, Florida....glad we got it narrowed down tonight.

I believe the Tallahassee NWS mentions in their discussion that they are pretty much discounting the Euro at this time because of it's "run to run" inconsistencies.

[KWT]

I tihnk the HWRF/GFDL ideas are going to bust way too far east, you can see how they've been calling for it to lift out north at this time and yet it keeps marching on westward...the area behind it will have even less chance of taking the HWRF track.

[tolakram]

Forecasters up here are talking about a huge shot of unseasonably cool air coming in next week as a front makes it well south of the area. That might be what some of the longer term models are seeing.

[srainhoutx]

HPC thoughts this morning...

...GULF OF MEXICO...
THE BEST CLUSTERING OF MODEL/ENSEMBLE SOLNS HAS ADJUSTED SOUTHWEST
FROM THIS TIME YESTERDAY WITH THE TRACK OF TROPICAL LOW PRESSURE
AREA FORECAST TO REACH THE WESTERN HALF OF THE GULF OF MEXICO.
THE 00Z CANADIAN IS NORTHEAST OF NEARLY ALL THE 00Z MULTI-MODEL
ENSEMBLE GUIDANCE AND COULD NOT BE USED NEAR THE GULF COAST. AS A
SURPRISE...THE 06Z GFS PARALLEL STUBBORNLY RECURVES THIS SYSTEM TO
THE NORTHEAST GULF COAST. A BLEND OF CLIMATOLOGY FOR LATE
JUNE/EARLY JULY AND THE ENSEMBLE GUIDANCE /WHICH HAS TRENDED AWAY
FROM THIS IDEA/ HAS LOWERED THE CHANCES FOR THIS OCCURRENCE TO
AROUND 15 PERCENT...SO THIS SOLUTION IS CONSIDERED A LOW
PROBABILITY ALTERNATIVE SCENARIO. BY THE LATTER HALF OF THE
PERIOD A COMPROMISE WAS MADE BETWEEN THE LAST COUPLE SHIFTS OF
PRESSURES IN REGARDS TO THIS SYSTEMS TRACK WHICH REMAINS A BIT
SOUTHWEST OF THE COORDINATED 23/16Z HPC/NHC POINTS YET CLOSE TO
THE 22/16Z COORDINATED POINTS AND BRINGS THE SYSTEM TOWARDS THE
US/MEXICAN BORDER LATE NEXT WEEK. EITHER WAY...RAINFALL IS
EXPECTED TO BE FOCUSED TO THE NORTHEAST OF THIS SYSTEM NEAR THE
FRONTAL ZONE DRAPED NEAR THE NORTHERN GULF COAST.

[tailgater]

The always entertaining NAM at 78hrs.

[ronjon]

Looks like 12Z GFS is taking a weak low across the Yucatan into the central GOM over the next 5 days. Most of the moisture is getting shunted into the NE GOM.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/carib/gfs/12/index_pcp_s_loop.shtml

[Ivanhater]

This is ridiculous.

[ronjon]

IH, what's so ridiculous? Models are being influenced by the trough - whatever forms here is eventually going to be shunted toward the NE GOM. However, with the shear present and model trends lately, looks to be pretty weak - mostly rain event.

[antonlsu]

Going to be interesting seeing what she does when she gets into the gulf.

[Ivanhater]

IH, what's so ridiculous? Models are being influenced by the trough - whatever forms here is eventually going to be shunted toward the NE GOM. However, with the shear present and model trends lately, looks to be pretty weak - mostly rain event.

Just the consistency ron. I don't understand how models like the euro that do develop this shunt it deep into Mexico and other off to the NE. It may develop into nothing more than a wave

[Ivanhater]

12z Nam...always a pretty one to look at lol

[Ivanhater]

12z GFS...no longer buries it into Mexico. Can't say they GFS has been consistent

[tolakram]

12Z GFS and CMC are now very similar in the short term, 0Z NOGAPS also similar to those two. CMC once again has rapid development in the gulf and a turn NE into Florida.