Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 3

[DoctorMu]

Bam. 1.21 inches overnight, soaking starting just before 3:30 am...Rain shield turned right and plowed right through the Aggie Dome. The sprinklers are finally OFF. A slight chance of rain on Wednesday before a cold front. Upper 80s to Low 90s until then and 80s afterwards.

[Ed Lizard]

[Srain]

The 12Z operational GFS suggests some late September/early October mischief in the Western Caribbean. That model is also hinting a rather strong EPAC Hurricane (currently 96E) impacting the Baja. Just perhaps some tropical moisture from the EPAC can be tapped increasing our rainfall chances across Texas.

[Ed Lizard]

The 12Z operational GFS suggests some late September/early October mischief in the Western Caribbean. That model is also hinting a rather strong EPAC Hurricane (currently 96E) impacting the Baja. Just perhaps some tropical moisture from the EPAC can be tapped increasing our rainfall chances across Texas.

Dr. Master's cancelled the season for Texas, but I remain glass 2096th full optimistic. Of course. Louisiana remains interesting well into October. GFS Hour 192 250 mb looks good for cirrus, at least for South Texas, from the likely EastPac storm.

Now, looking beyond day 10 on some of the ensembles, Texas might get into a better position for some serious moisture if we had an East Pac storm develop after 96E. Few people forget the excitement of former EPAC Hurricane Rosa.

[Ed Lizard]

Euro now has Hilary makinng landfall, but that stupid ridge may deflect most of the mid level fun away from us.

Stupid ridge.

[Srain]

The SPC is mentioning a chance very slight chance of storms this afternoon/evening for our area. It does appear that better chances will be to our W near Austin/San Antonio. Regarding Hilary in the EPAC. It's still too soon to write off any affects from that disturbance, IMO. We all know how things can change re: ridge placement and the synoptic pattern. The Pacific is very noisy right now and a transition is beginning to a pattern where the MJO will begin to influence the overall pattern. Some wrote off the effect of any MJO as it has been very quiet, but there are changes ahead and October could bring an interesting pattern. We will see...

[Ed Lizard]

End of the HELL RIDGE of DEATH???!!!77!!11!7???

Not even some maybe the trough pinches off stuff, this is actually a piece of a trough entering the Pacific coast that pinches off and wanders!!!!!!

[Quixotic1]

End of the HELL RIDGE of DEATH???!!!77!!11!7???

Not even some maybe the trough pinches off stuff, this is actually a piece of a trough entering the Pacific coast that pinches off and wanders!!!!!!

I'm tired of seeing the 30C isotherm parked over Texas, run after run.

[Ed Lizard]

I'm tired of seeing the 30C isotherm parked over Texas, run after run.

Better than nothing.

[Quixotic1]

Better than nothing.

]

Don't mind me. I'm just trying to keep my hopes down!

[Ed Lizard]

106ºF in ACT, a new daily record.

Not a totally dry forecast.

[Srain]

The 12Z WRF meso model continues to sniff out a chance of showers/storms in the mid week time frame. Let's hope that piece of upper level energy is correct and we see at least a chance of isolated activity before the front sweeps by and dries us out, once again...

[DoctorMu]

We're about to get nailed harder than a NOLA hooker on Father's Day.

A good size set of cells has turned right towards CLL. Hope we get a few inches....of rain out of this.

[TXWXCHX]

We're about to get nailed harder than a NOLA hooker on Father's Day.

A good size set of cells has turned right towards CLL. Hope we get a few inches....of rain out of this.

We got NO rain out of that cluster tonight... even though I was right in the middle of it But what I DID get was a temperature spiking to 95 degrees (+5), with winds gusting to 40MPH and humidity dropping to 21% - at 11:30PM!! A mini heat burst, perhaps?

[DoctorMu]

We got NO rain out of that cluster tonight... even though I was right in the middle of it But what I DID get was a temperature spiking to 95 degrees (+5), with winds gusting to 40MPH and humidity dropping to 21% - at 11:30PM!! A mini heat burst, perhaps?

It collapsed exhausted over us. Maybe 1/2 inch. Shrinkage.

[TXWXCHX]

It collapsed exhausted over us. Maybe 1/2 inch. Shrinkage.

I'll take that half inch!! I'm a desperate woman...

[Srain]

Morning e-mail from Jeff:

A slight chance of strong to severe afternoon/evening thunderstorms over the region today and again on Wednesday and Thursday.

Upper air pattern shows weak to moderate westerly flow aloft over TX this morning on the SW side of an large upper level low centered over the western Great Lakes and Midwest. Weak surface frontal boundary tied to this low has become stationary along a line from roughly Shreveport, LA to Brownwood, TX. South of this boundary a moist and fairly unstable air mass resides. As seen yesterday afternoon/evening over central TX, weak shortwaves embedded in the westerly flow resulted in enough lift over this boundary to fire off strong thunderstorms.

Water vapor shows a slow moving short wave over NC TX this morning with an upstream impulse near the Big Bend region moving eastward. Combination of strong surface heating, moisture advection, weak frontal boundary, and incoming impulses from the west should result in isolated to scattered thunderstorm development by late afternoon from central TX into central LA or roughly from Del Rio to Fort Polk. 00Z 4km WRF shows storms developing on what appears to be a southwest moving outflow boundary this afternoon from the large MCS ongoing over N LA/C MS this morning, with activity focused today over SW LA and over C TX. While this is possible given the outflow boundary moving SW on the central LA radars, expect other development to focus near/along the stalled frontal boundary once temperatures reach the upper 90’s to near 100.

Strong surface heating and dry sub cloud layer especially west of a line from San Antonio to Columbus to Huntsville will support the threat of strong winds near/under any thunderstorms this afternoon as convection will be high based and evaporation effects under the cloud bases will bring strong downburst winds toward the surface. SPC Day 1 outlook does suggest an isolated severe wind threat this afternoon/evening from roughly Austin to Fort Polk, LA and then again on Wednesday afternoon from Del Rio to Lake Charles. Chances of thunderstorms look the best on Wednesday as the weak frontal boundary slowly sags southward likely aided by outflow boundaries from the previous day convection and stalls near I-10. The next 48 hours looks like the best shot of rainfall across the area for the next 7 days, so hopefully some areas will get some relief.

Friday-Weekend:

Stronger front on tap for Friday which should actually bring about a decent air mass change for early October. Front should cross the coast sometime on Friday afternoon with Canadian high pressure building into the region. Dry northerly flow will continue through the weekend with lows in the 50’s and highs in the 80’s.

Fire Weather:

No great concerns in the near term as RH will remain on the higher side and winds light. Lightening near thunderstorms mainly north of HWY 105 could start a few fires given the extremely dry fuels, but forward spread of any fires should be slow. Toward the weekend, conditions may become increasingly elevated as a much drier air mass and stronger winds come to bear behind a cold front on Friday. Could see elevated to near critical conditions both Saturday and Sunday, but at this time winds looks to remain below Red Flag criteria.

[Ed Lizard]

It is the GFS, and beyond the resolution chop, but the big trough late next week, while we're well South of the main energy, 700 mb and 850 mb windfields suggest capping would not be an issue.

I've noticed this in the past, it often seems that troughs with a negative tilt are much less likely to cap us. I remain glass half full. I also think DFW area may be at risk for a significant severe episode late next week.

[Srain]

It is looking more likely that a nice pattern change is ahead. A rather vigorous West Coast trough looks to possibly increase rain chances across the area with disturbances riding along a bit more active sub tropical jet as the sleepy MJO begins to awake. It has been a very long time since we've seen a pattern like this and let's hope it is real and not just some model fantasy...

[msp]

thunder and lightning and no rain. plenty o' t-storms to the south, though. 80s will feel great next week.

[bubba hotep]

Nice batch of surprise storms have popped up in the last couple of hours over Collin county

[Ed Lizard]

More lightning then rain again, but enough rain I won't water the lawn until Sunday.

A lot of lightning, really.

[Srain]

A pattern change continues to be advertised by guidance as we enter the first week of October. A deep West Coast trough and an active Pacific sub tropical jet that includes an possible EPAC Hurricane heading NE look to offer chances for increased moisture over Texas. Also, right on schedule, a vigorous cold core upper low appears to be setting the stage the first significant snowfall of the season for the Rockies. A sure sign the fall has finally arrived...

[Ed Lizard]

I will say, unless the modelling changes soon, I will soon give up hope for an October tropical system for Louisiana. GFS still has Carla Cradle storms out towards two weeks, but ensemble and operational heights suggest the best that can be hoped for is Florida. Central America South of the ridge axis as well, of course.

[DoctorMu]

I will say, unless the modelling changes soon, I will soon give up hope for an October tropical system for Louisiana. GFS still has Carla Cradle storms out towards two weeks, but ensemble and operational heights suggest the best that can be hoped for is Florida. Central America South of the ridge axis as well, of course.

An active subtropical jet is my best hope for catch-up in October...bring on the training! I'll even take the lawn brown patch.

This tropical season in the GOM: c'est mort.

[Srain]

Throughout the weekend the signals have increased suggesting a change in the pattern. While we are enjoying cooler temps and the dry pattern continues, the ensembles are suggesting a rather significant change beginning next week. As mentioned earlier, the non existent MJO that we experienced for most of the summer is making a return, and in a big way. We have experienced rather weak pulses of the MJO, but that is about to change. There is a robust Kelvin wave and an MJO induced Western trough lurking in the medium/longer range. This MJO almost looks like an El Nino type pulse because of the strong nature that the ensembles are suggesting. Now what can we expect in a pattern such as this. There should be an uptick in tropical activity, first in the EPAC and then in the Western Atlantic Basin. Also, it appears that the Pacific sub tropical jet will become rather active as impulses ride along the Western trough. There is a rather strong possibility that an EPAC Hurricane or two will turn NE recurving into Mexico and points to the N and E. There are also hints of tropical development in the Western Caribbean in the not too distant future. While we in Texas are probably done with any tropical threat, eyes may need to look just to our E along Louisiana/Mississippi/Alabama/Florida areas. Our weather may begin to be affected with any activity in the EPAC as well. Typically the first couple of weeks of October are rather tranquil for Texas. With the above mentioned scenario, the second half of October may provide for a switch from the weather doldrums we have experienced for months on end. We shall see...

[bubba hotep]

What a perfect night for an ice cold draft here in Austin but back to DFW tomorrow boo!

[Srain]

Morning e-mail from Jeff:

Interesting pattern ahead for the southern US and TX

Surface high over the region will slide eastward with dry easterly winds continuing for another day or so before winds become more SE and Gulf moisture begins to return. Will see one more night of cool weather before lows return into the muggy 60’s and 70’s. ESE to SE flow ahead of the next western US long wave trough will help return moisture to the region by Thursday. Models show a slight chance of streamer type showers moving inland off the Gulf during the day on Thursday and mainly focused over the coastal bend where best moisture and likely a coastal boundary between modified Gulf air and true tropical Gulf air will set up. Large slow moving upper trough will eject more northeast into the upper plains instead of eastward into the central/southern plains due to ridging over the SE US.

Result of this pattern will be true tropical moisture invading the region by Friday with PWS progged to increase into the 1.5-1.8 inch range. Feel that the best dynamics from embedded short waves in the SSW to SW flow on the eastern side of the trough will be focused along and W of I-35 and this is where the best rain chances will reside. The dividing ground between a wet west TX and a fairly dry east TX looks to be across SE TX with the best rain chances on Friday and Saturday west of I-45 and likely near Matagorda Bay while areas east of I-45 may see no rainfall at all. Models are not in overall good agreement on the track and speed of the trough over the western US, but such long and deep systems tend to move slower than forecast, so rain chances may end up lower on Friday and higher on Sunday just due to a slower progression of the system into the plains. Will fine tune over the next few days and hopefully be able to tick rain chances up a touch!

Gulf:

The old frontal boundary which moved through TX last Friday has found its way down into the western Caribbean where it has stalled out this morning. Satellite shows a disorganized area of showers near this boundary from south of Cuba to the central American coast. Several models have been hinting at sub-tropical or tropical cyclone formation within this region by this weekend and lift the system northward into the region of the eastern Gulf of Mexico/S FL/Cuba over the weekend. ECMWF is by far the more aggressive model with the GFS much weaker. Upper pattern over the SE/E US is interesting for early October with what appears to be enough ridging to block much northward motion of the system near FL. Much uncertainty with where/how this system forms and tracks and how purely tropical it becomes. For now TX should lie well to the west, but surface flow may be increased out of the ENE/NE by early next week pumping dry air SW toward eastern TX and increasing gusty winds…fire weather concerns may be increased.

Fire Weather:

Dry fuels and dry air mass continues to support elevated fire weather conditions even with weak afternoon winds. At least 20 grass fires have developed across Harris County over the past 3 days in conditions that are marginal for fire growth…this continues to give the indication of how serious of a fire weather situation remains across the area awaiting favorable weather conditions. The good news is that the very dry air mass in place should be replaced with increasing Gulf moisture by Thursday, but stronger winds. Will retain the elevated fire threat into Thursday as we swap out the dry air but then bring in gusty winds. Feel starts will be harder with the more moist surface layer, and potential for some rainfall.

Next time period of concern may come late in the weekend/early next week as deepening eastern Gulf system could bring gusty NE winds and dry air into the area.

[Ed Lizard]

Dr. Jeff writeup, quite depressing.

I'm hoping the EPAC action comes in far enough West for the old Rosa scenario. But I'm not holding my breath. Out in fanstasy land 6Z GFS shows an apparent spinup headed for Mexico or deep South Texas, but second half of October, I strongly doubt that.

[DoctorMu]

Seabreeze kicking in, but spotty showers appear to be fizzling just N of I-10. Isolated to scattered through Sunday...rain dance time.