Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 7

[NTXYankee]

HRRR trolling us again?

Eventually the model will be right again.  Perhaps it was an early April Fools joke this past week.

[Quixotic1]

Eventually the model will be right again.  Perhaps it was an early April Fools joke this past week.

 

It's all gravy.  I think next week will provide a fix if our meager chances this evening don't pan out.  

[bubba hotep]

Interesting, CU field is popping well behind the dry line

[NTXYankee]

Interesting, CU field is popping well behind the dry line

FWD mentioned this in their AFD, said could be a sign of some lift coming in.

[bubba hotep]

Maybe next week?

[NTXYankee]

Maybe next week?

Hopefully but not getting overly excited. FWD said our friend the cap will visit again and would be breakable with short waves in the SW flow that can't be determined yet. My bet is on one not showing up given this year so far, so depressing to have the dryline so close and nothing, even though that was the more likely scenario anyway.

[Roy]

Yeah, continuity is the best bet. May look good, but just assume we will get no decent shortwaves at this point yet until a true pattern change happens. Something will change at some point...the question is just when.

[bubba hotep]

AS FOR THE WORK WEEK....AN UPPER LOW CURRENTLY NORTHWEST OF
SEATTLE WILL DIG ALONG THE WEST COAST THROUGH MONDAY...THEN MOVE
EAST ACROSS THE CENTRAL ROCKIES AND FINALLY INTO THE MIDWEST ON
FRIDAY. THIS WILL KEEP NORTH/CENTRAL TEXAS UNDER PERSISTENT
SOUTHWESTERLY FLOW ALOFT AND SOUTHERLY LOW LEVEL FLOW. FORECAST
SOUNDINGS INDICATE THAT WE WILL BECOME AND REMAIN CAPPED FOR MUCH
OF NEXT WEEK...BUT WE COULD HAVE SOME SHOWERS/THUNDERSTORMS IN THE
AFTERNOON/EVENING HOURS WHERE THE CAP IS THE WEAKEST . WEDNESDAY
IS THE ONE DAY THAT THE CAP WEAKENS AS A FEW SMALL UPPER
DISTURBANCES MOVE OVER THE REGION. ANY THUNDERSTORM THAT DEVELOPS
NEXT WEEK WILL BE CAPABLE OF BECOMING STRONG TO SEVERE. LARGE HAIL
WILL THE MAIN THREAT DUE TO VERY HIGH CAPES VALUES.

[Roy]

Yeah, I am assuming nothing will happen until Maybe Wednesday or Thursday. CIPS Analogs that I discovered from another thread look great for Thursday with some Wednesday potential, but before....nope.

[vwgrrc]

Yeah, I am assuming nothing will happen until Maybe Wednesday or Thursday. CIPS Analogs that I discovered from another thread look great for Thursday with some Wednesday potential, but before....nope.

wouldn't the cap be in place for dfw metro?

[wxmx]

After a 2 week hiatus, rains reappeared with a vengeance. A little above 2", most of it during a TS and 2" rates for 40 minutes.  April averages around 1.1", so this is the 6th consecutive month of above average rainfall, with 26 more days to go for the month.

 

It has been drizzling after the fropa, probably adding a tenth or two after the drenching rain.

[Roy]

Yeah the cap's what stops anything until Thursday, maybe Wednesday in the western sections. Those analogs are pretty interesting in that they do closely match the NWS forecast.

[NTXYankee]

Still on the fence for Thursday around DFW, further east of course looks good. GFS moves the dryline through around 18z to 21z, not great timing for this area but Euro from data that can be seen looks to be a bit slower hanging it up just west of Fort Worth. I would like to see a slow down of the dryline before getting excited, otherwise I believe our chances are slim to see anything exciting around here.

[1900hurricane]

QPF from the 12Z ECMWF looks somewhat supercellular across NE TX.

[bubba hotep]

Still on the fence for Thursday around DFW, further east of course looks good. GFS moves the dryline through around 18z to 21z, not great timing for this area but Euro from data that can be seen looks to be a bit slower hanging it up just west of Fort Worth. I would like to see a slow down of the dryline before getting excited, otherwise I believe our chances are slim to see anything exciting around here.

 

Yeah, Euro looks like it has the dryline as far west as Wichita Falls at 18z.  That is a good bit farther west than the GFS and I know what model I'm going with. However, this far out it is impossible to pin down the position of the dryline but even a few hours slower could make a huge difference. 

[bubba hotep]

QPF from the 12Z ECMWF looks somewhat supercellular across NE TX.

 

Was just thinking that. 

[1900hurricane]

Even if the weekday storms don't pan out, the ECMWF has been throwing something big out for Texas on Sunday.

[aggiegeog]

I got around 1.25" yesterday with the treo never reaching 55 until the evening.

[Roy]

Yeah the dryline position is vital. Will see how this unfolds.

[Quixotic1]

Nice TSRA this morning.  My two year old caught it before I did.  "What's that noise daddy?"

[NTXYankee]

Even if the weekday storms don't pan out, the ECMWF has been throwing something big out for Texas on Sunday.

I've been watching that system a bit and so long as it's track stays where it is and a negative tilt would be nice with it Sunday does have some good potential, maybe even Saturday along warm front.

[NTXYankee]

Well whether this trend holds or not remains to be seen, but both the NAM and GFS for the 18z run have slowed the dryline down and park it just west of DFW Thursday afternoon for initiation of storms, close to the Euro location. NAM lights up the dryline too with some nice looking cells. Weekend continues to look interesting as well, so maybe we'll finally see this boring stretch end.

[Srain]

After a quiet and benign weather pattern the past couple of weeks we are beginning to transition to a bit more active pattern. For the most part our sensible weather will consist of a fast zonal flow off the Pacific across the Southern United States with a rather active Polar jet that has retreated N across Canada and the Northern Plains. The persistent eastern trough that has plagued the Lower 48 most of the late Winter/early Spring is about to transition to that of a Western trough allowing storm systems to dig S into the Pacific NW and California. The first in a series of storm systems is spinning off the Northern California Coast this morning and will begin to trek inland and ENE setting the stage for severe weather across the Plains and the Great Lakes Region tomorrow into Thursday. This storm system will carve out a trough across the West allowing a Pacific cold front to slowly advance S into our Region Thursday into Friday and stall somewhere near or just S of the I-35 Corridor of Central Texas. PW's continue to increase each day as rich tropical moisture near or above 2 standard deviations above normal become established across the Southern half of Texas into Louisiana.

By Friday a second storm system begins to dive further S along the West Coast and move inland near San Diego. As this storm system moves across Northern Mexico over the weekend and begins to turn NE Sunday, the guidance is beginning to suggest the mean trough axis could take on a more negative tilt meaning strong to severe storms begin to increase across Texas beginning Saturday and increase in areal coverage on Sunday into Monday. Very high moisture valves with veering winds across the multiple levels suggest some potential for rotating storms particularly Saturday afternoon along a dryline across West Central Texas. Storms are expect to organize across the high Plains of the Sierra Madre front range just West of South Texas and spread NE.

 

 

 

 

 

 

[Srain]

Morning briefing from Jeff:

 

After a couple of dry weeks…two storm systems will affect the area late this week and this weekend…both severe weather and heavy rainfall will be possible.

 

Onshore flow continues to stream moisture inland off the Gulf of Mexico this morning with dewpoints running in the upper 60’s and lower 70’s. Zonal flow aloft with strong capping overhead will negate any rainfall chances today and for the first half of Thursday with partly cloudy skies and breezy conditions.

 

Thursday-Friday:

First upper level storm system ejects out of the SW US and toward the central plains with a trailing cold front moving into the area late Thursday and on Friday and stalling. Air mass south of this front Thursday afternoon becomes moderately unstable with forecasted CAPE values of 1500-2500 J/kg and steepening lapse rates aloft. Surface heating into the mid 80’s will help to erode the weakening aping inversion and expect at least isolated storms to develop along the front. Any storms that develop will pose a hail and damaging wind threat with the best chances from College Station to Lufkin Thursday evening.

 

Front sags southward on Friday and expect another active convective day Friday afternoon. Weak short wave will cross the area in combination with the surface front likely producing scattered thunderstorms in the heat of the afternoon. Guidance is really pegging Friday afternoon/evening to be fairly active. Again the air mass will be fairly unstable and strong to severe thunderstorms will be possible. Shear profiles are not overly favorable for tornado production, but large hail and wind damage appear the main threats. SPC has already outlooked much of the area for a slight risk of severe weather Friday afternoon.

 

Saturday:

Front remains stalled across the region and this will linger thunderstorm chances all day Saturday. Think the best chances will be in the afternoon hours with surface heating, but much of this depends on how much development there is Friday afternoon and if the air mass is “worked over” and needs time to recharge.

 

Sunday/Monday:

Much stronger and deeper upper level system approaches the region Sunday and Monday and this system will certainly bring impacts if the current model projections hold. Old surface front will move northward as a warm front on Sunday and with lift increasing, showers and thunderstorms will once again erupt along and north of this boundary. Severe weather will be possible Sunday afternoon with increasing instability and shear values.

 

Main upper level system moves across the area late Sunday into Monday with numerous thunderstorms expected. Threat may transition from severe weather to heavy rainfall and flash flooding especially given the increasing saturated grounds after severe rounds of thunderstorms. Latest model guidance really pegs the area Sunday night into Monday morning with heavy rainfall and several flash flood factors appear favorable during this period including a good feed of moisture off the Gulf, a slow moving boundary, and exceptionally high moisture content of the air mass (PWS nearing 1.7 inches). Will also support a severe threat with a favorable splitting jet stream structure aloft and cooler mid level temperatures advecting over the warm surface air mass. Main threats appear to be large hail and wind damage, but tornadoes may also be possible.

 

[1900hurricane]

Models have down by about half a day today with Sunday's system. Not a good omen for me who was hoping to chase.

[bubba hotep]

Blehhh.... elevated showers today and a dry frontal passage tomorrow? Maybe the front will be on the slower side of guidance tomorrow but it will probably be on the faster side, given our luck so far this spring

[Roy]

Ugh. Tech WRF is now initiating much father east tomorrow it looks to me. DFW may be screwed over again....I expected I would but it looked okay for the far east side at least. Really sick of this. Even the rain we are getting is pitiful, such as the spit showers today that barely amounted to anything.

[radarman]

Small hail in S Ft. Worth

[Roy]

Nice little storm with some small hail last night in North Ft. Worth. Very little rain, but quite a thunder event.

[bubba hotep]

Nice little storm moved through my area early this morning. Now to watch the progress of the cold front today to see if things will get interesting around DFW or not this afternoon.