Possible NW Gulf Development Late This Week?

[Ptarmigan]

I notice there is an area of clouds in the Bay of Campeche. Any possibility for development?

[BigA]

Too much shear now. GFS and NOGAPS decrease shear in the GOM later this week. CMC disagrees. If shear falls, it´s worth a look.

[Aric Dunn]

yeah but its going to take a while before anything gets going.. there is some models support for that area. but just keep an eye on it..

[Ptarmigan]

Would be nice to get rain from it.

[LaBreeze]

Local met mentioned tonight that we should keep an eye on that area later in the week.

[storm92405]

LaBreeze what channel was you watching. Who said it. I looked at the GFS earlier and it has a weak low developing moving north paralleling the texas coast making landfall in LA. Maybe we can get some rain out of it. Do you have this website. You can access some Tropical Cyclone models. Here it is. http://moe.met.fsu.edu/tcgengifs/

[O Town]

Nice blow up earlier today, but you can tell by just watching this loop that it is pretty hostile in gulf and BOC.
Worth keeping an eye on tho.

[Comanche]

Every time we get a good chance at soaking rains in the forecast, it fails to materialize.

Me and my grass=0
Chinch bugs=1

Funnel that moisture here PLEASE!!!

[wxman57]

I thought that would get your attention. I don't start many threads, maybe only 10-15 since I've been a member in the past 6-7 years. But I thought that the chance of development in the NW Gulf in 4-5 days might be significant enough to warrant a thread.

I'm taking a look to see where this GFS low comes from in the NW Gulf late this week. Looking really closely at 850mb vorticity and 500mb heights (plotted to every 2 meters from 12Z GFS) I can see a vorticity center move across the isthmus of Mexico tomorrow into the BoC then slowly northward off the coast of Mexico. On Thursday, the GFS shows a weak (really weak since I'm plotting heights every 2 meters) short wave moving eastward across northern Mexico. The two collide offshore NE Mexico late Thursday. The GFS goes from a very weak trof at 18Z Thursday to a closed low at 21Z off the TX coast. By 12Z Friday, there's a closed low off the TX coast. It moves ashore into SE LA Saturday night/Sunday morning.

European and Canadian models show something similar - weak low forming by Brownsville and moving inland along a weak cold front on the mid Gulf coast Sunday morning. I can't tell the origins of the low on the CMC and EC models, as detail isn't high enough.

Let's see what a WV loop reveals. It does confirm the GFS prediction of a mid-level high building over the south-central Gulf. Can see it clearly. It's the southern side of this high that the moisture rides off the East Pac into the BoC, at least according to the GFS. The MIMIC TPW loop shows increasing moisture across the western Gulf, but a bit of dry air moving across the Yucatan into the eastern BoC now. Can't see what's actually over land as far as moisture, but WV doesn't show any significant single disturbance down there.

What about UL winds? 12Z GFS indicates an upper-level ridge over the SW BoC today and 30-50 kt westerly winds (200mb) to its north off the upper Mexico coast and Texas coast. By Wednesday, that high moves west and inland into MX, and winds off NE Mexico go WNW at 30-45 kts (TX, too). For Thursday, a digging trof kicks those westerly winds up to 35 kts down by Brownsville and 50-60 kts across the NW Gulf to 90W, then 40-50 kts east of there to Florida. VERY strange by 12Z Friday. GFS has 50 kt WSW-W winds from Brownsville to Florida, north of 25N. But JUST south of 25N off NE Mexico the GFS has a weak anticyclone over the developing low. Winds just go from 50 kts to 10-15 kts in about a degree of latitude. By Friday evening, winds from offshore NE Mexico to SE LA are from the SW at 25-40 kts.

So what does this all mean? GFS and Euro agree on fairly deep upper low over Nebraska by this coming weekend, with a cold front boundary to the NW Gulf by Saturday morning. This could certainly enhance thunderstorms across the NW Gulf on Friday. However, the setup is not at all similar to Humberto with respect to the upper air pattern. Winds aloft really don't look favorable for a purely tropical cyclone this week. Could be a hybrid-type low that forms on the front Friday/Saturday, moving inland very quickly. If the GFS upper wind predictions are right then whatever is making landfall from LA to the coast of AL is going to be embedded in moderate SW flow aloft, so it would be a sheared system. Chances of something like this becoming a hurricane would seem low.

I think that there is a very good chance that the GFS is overdoing the low center. I've seen such things many times before. And the way that the GFS just pops that 500mb low off NE Mexico between 18Z-21Z Thursday is incredible. Of course, I'm looking at 2m height intervals to see it, so maybe it's not as dramatic. But I do think that there is enough model agreement that "something" might try to spin up in the western Gulf that we should consider calling attention to the possibility.

I'd like to take a look at tonight's 00Z model runs and see if they agree with today's 12Z. Possibly even look at tomorrow's 12Z GFS run before concluding that development may occur. Right now, I'd give the chances at 5-10% of something forming (TD/TS/STS).

Thoughts, anyone?

[Diva]

Based on my luck lately, I would say that it is highly likely that the upper TX coast (SETX-SWLA border) will get a strong enough storm this weekend to produce a power outage because my deep freeze is full right now!
Of course this is my highly un-scientific opinion and is only based on prior Hurricane experiences!

[Sanibel]

Edit: Lacking in convection.

[CYCLONE MIKE]

Only comment I can say is I will believe it when I see it. One or more models have shown some type of development in the gulf every other week this season and nothing except for claudette. Just this past weekend a weak low supposed to develop in the gulf and move ashore in south LA and give us good rains. Never happened, not even a drop of rain at my house saturday and maybe a quater inch yesterday. And really for the last month it has been mentioned in the nws discussions about something forming every week due to stalled out fronts in the gulf and nothing. Not complaining, just arguing the point.

[wxman57]

Only comment I can say is I will believe it when I see it. One or more models have shown some type of development in the gulf every other week this season and nothing except for claudette. Just this past weekend a weak low supposed to develop in the gulf and move ashore in south LA and give us good rains. Never happened, not even a drop of rain at my house saturday and maybe a quater inch yesterday. And really for the last month it has been mentioned in the nws discussions about something forming every week due to stalled out fronts in the gulf and nothing. Not complaining, just arguing the point.

I'm certainly aware that the GFS develops a bogus low in the Gulf on most runs, but usually at the end of the runs. This is a 3-4 day forecast vs. a 14 day forecast. And the EC and CMC do agree, somewhat. More than likely, it'll turn out just to be an area of increased thunderstorms (that'll miss us in Houston) and a bit of rough seas offshore on Fri/Sat.

However, it is something worth keeping an eye on. Probably more so for potential beneficial rain to TX/LA than any other reason, though I fear it'll be east of Texas.

[tailgater]

Yes 57 I didn't want to start a thread but also noticed that NAM and ETA have been hinting at something also but seem more bullish on something trying to get going in the central GOM. Thoughts?
Correction on the latest run NAM also develops a low in the BOC.

[Aric Dunn]

yeah the L.A weather office the other day mentioned this possibility.. will be interesting..

[tailgater]

New Orleans AFD
LONG TERM... FRIDAY WILL BE A TRANSITION DAY FOR THE PATTERN. BOTH GFS AND ECMWF BRING A CLOSED UPPER LOW INTO THE NORTHERN PLAINS OVER THE WEEKEND BEFORE MOVING IT INTO THE GREAT LAKES. AN IMPULSE GETS ADVECTED OUT OF NORTHERN MEXICO AHEAD OF THE UPPER TROF...AND SOUTHWESTERLY FLOW AHEAD OF THE IMPULSE PUMPS MASSIVE AMOUNTS OF MOISTURE INTO THE AREA FOR THE WEEKEND. FORECAST PRECIPITABLE WATER VALUES IN EXCESS OF 2.25 INCHES FOR SATURDAY AND SUNDAY. WITH SURPRISING CONSISTENCY BETWEEN THE MODELS ON THIS SCENARIO...HAVE OPTED TO GO WITH LIKELY POPS FOR SATURDAY AND SUNDAY. MAIN IMPULSE FORECAST TO MOVE BY ON MONDAY AND WILL DROP POPS BACK INTO THE CHANCE RANGE. CLOUDS AND PRECIPITATION SHOULD HOLD TEMPERATURES BELOW CLIMATOLOGY. 35

Sounds like they think it'll just be a lot of rain

[LaBreeze]

Yeah, local met has bumped up the precip chances to 60-70% for Sat, Sun, and Mon.

[LaBreeze]

LaBreeze what channel was you watching. Who said it. I looked at the GFS earlier and it has a weak low developing moving north paralleling the texas coast making landfall in LA. Maybe we can get some rain out of it. Do you have this website. You can access some Tropical Cyclone models. Here it is. http://moe.met.fsu.edu/tcgengifs/

Storm92405, I was watching channel 3 KATC in Lafayette. Local met was Rob Perillo. He's bumped the precip chances up to 60% for Sat., Sun., and Mon.

[Kludge]

Tease.

Move along folks...nothing to see here.

WxMAN57 ---> Hypes a possibility, gets the drought victims excited, then calls in "Bones", and laughs at all who actually thought that beneficial tropical rains were forthcoming.

In the midst of a highly sheared, "the boy" (I speak english, though some call it "el nino") year, this is almost sadistic.

I respect WXman57's knowledge and professionlism. He's got to be bored-to-tears with this season. He's started this thread for good reason. There is a threat late in the week, in my opinon.

I just hope he doesn't disappoint by talking down to those of us that hop on the potential-rainmaker train that these models forecast, if things don't pan out. This drought isn't a novelty anymore...it's dead serious.

[Wx_Warrior]

South Texas badly needs rain.