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

[jhamps10]

I just ventured out and there is a LOT of tree damage around my area in SW ft worth

[jm1220]

I just ventured out and there is a LOT of tree damage around my area in SW ft worth

Glad to see you made it out okay, not even power lost. 80+ mph winds are pretty scary and can do a lot of damage. I experienced winds like that during Sandy and trees/power lines were down everywhere and even some roofs were damaged. 

[jhamps10]

Glad to see you made it out okay, not even power lost. 80+ mph winds are pretty scary and can do a lot of damage. I experienced winds like that during Sandy and trees/power lines were down everywhere and even some roofs were damaged. 

 

if it wasn't for the fact that we have underground utilities with the exception of the main transmission lines which are steel, I think we would have had a massive power outage in this part of town. I was waiting for it to go out, it did flicker once, but that was only as it was hitting the areas SW of the city. just outside my building there's a huge limb down, however that one looked more like it could have been lightning related more than wind  IMO with how the branch sheared off from the trunk. just down the street a tree fell and really destroyed a steel fence, however that tree was clearly weakened to begin with if not already dead. However the worst of the damage was along Bryant Irvin Road just to my NW, the sign at the ford dealership was leaning when the other day it was perfectly straight. 

[bubba hotep]

00z NAM 4K hammers DFW tomorrow, taken verbatim, serious flash flooding threat at a minimum. 

[bubba hotep]

A storm that looks like it nearly has rotation, has been dropping large hail offshore from Grand Chenier, Louisiana. I saw a "marine hail report" in GRLevel3. Never seen a marine hail report before.

 

 

 

I've spent a lot of time fishing the coastal marshes in Louisiana and have never seen hail down there. In fact, I can only remember it hailing a couple of times the whole time I lived in southern Louisiana. 

[jhamps10]

00z NAM 4K hammers DFW tomorrow, taken verbatim, serious flash flooding threat at a minimum. 

 

interesting... wanna post images if you can for that

[cstrunk]

interesting... wanna post images if you can for that

 

You can use this link.  Just click on NAM 4KM then find Simulated Reflectivity for the 00z run.

 

http://www.weather.cod.edu/forecast/

[jm1220]

Yuck, the humidity's been back here for a few hours now. For tomorrow's severe weather threat, it's a good sign. The heat today at least was with low dewpoints for a few hours. Blechh. 

[bubba hotep]

One of the big things to watch today for the DFW area will be moisture return and it appears to be surging north this morning.  Also, how much junk convection we get earlier in the afternoon.

 

 

[bubba hotep]

Unlike Friday, the stationary boundary is up near the Red River and not along I-20. Also, lapse rates are much more impressive today.

[NTXYankee]

Yeah looks like a day of radar watching again. Yesterday looked like timing was going to be an issue with it being overnight and cap during the day. Now doesn't look like that is the case. Still skeptical but there is some concern there for something significant impacting the metroplex.

Temps and moisture having no problems climbing this morning.

[bubba hotep]

Yeah looks like a day of radar watching again. Yesterday looked like timing was going to be an issue with it being overnight and cap during the day. Now doesn't look like that is the case. Still skeptical but there is some hope there for something significant impacting the metroplex.

Temps and moisture having no problems climbing this morning.

Moisture is really flooding in at the low levels. With so many moving parts today, it wouldn't take much to shift the main tornado threat area a 100 miles or so to the ENE. Also, could work just as easily in the other direction leaving DFW safely out of the tornado risk.

[bubba hotep]

Storms already firing to our west and south and it looks like a watch is coming in not too long. I would think this first round of convection might limit the upper bound of the potential later today?

[jhamps10]

On my iPad but moderate risk for DFW metroplex as of 1130 update

[jojo762]

SPC introduced the significant severe hatched area for tornadoes... Including DFW metro... And introduced a MDT risk now as well.

[jhamps10]

SPC introduced the significant severe hatched area for tornadoes... Including DFW metro... And introduced a MDT risk now as well.

I noticed that on my quick glance at the update... We have the one thing today we didn't have we'd, Friday and that is sunshine.... Could get nasty later

[Roy]

Yeah, moderate now....interesting. 

[jojo762]

I noticed that on my quick glance at the update... We have the one thing today we didn't have we'd, Friday and that is sunshine.... Could get nasty later

indeed, no early day convection to ruin anything... another thing you have going for you today is the High-Res models (at least earlier) were showing somewhat widespread discrete supercells... Transitioning to clusters of course...

[Roy]

How will the showers to the west impact things? Not very much I would think since pretty small area and temps already have warmed up here and past that little area closer to the dryline. Clouds moving in, but no real impact I think with temps already getting close to 90.

[bubba hotep]

Leaving church and temps are in mid 80s with orphaned anvils off to the S & SW.

[jm1220]

Yikes, this one snuck up on us. Slight yesterday, today enhanced and a moderate area? 

 

The indices look favorable for sure (CAPE, shear, LI), and the clouds aren't a major issue like on Friday. 

[jhamps10]

We're clouded over in west ft worth but temps near 85 on the theromoter... Seeing some cu mini towers trying to form to my south attm, not seeing a lot of development in the showers right now but I think the atmosphere was already primed by the bright sunshine until the anvils blew overhead

[bubba hotep]

Derecho!? 

 

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
1239 PM CDT SUN APR 26 2015

.UPDATE...

...MESOSCALE FORECAST UPDATE REGARDING THE FORECAST FOR SEVERE
STORMS ACROSS NORTH AND CENTRAL TEXAS TODAY...

12Z UPPER AIR ANALYSIS SHOWED AN INTENSE UPPER LEVEL TROUGH
LOCATED OVER THE SOUTHERN ARIZONA AND NEW MEXICO BORDER. 500 MB
HEIGHT FALLS OF 6 TO 12 DM WERE OBSERVED DOWNSTREAM OF THIS UPPER
TROUGH...AND THE MAGNITUDE OF THESE HEIGHT FALLS IS INDICATIVE OF
STRONG LARGE SCALE FORCING FOR ASCENT TO THE EAST. AT THE 700 MB
LEVEL...A PLUME OF STEEP MID-LEVEL LAPSE RATES WAS OBSERVED...WITH
A TEMPERATURE DIFFERENCE IN THE 700 TO 500 MB LAYER OF 22 DEG C
LOCATED SOUTHWEST OF NORTH AND CENTRAL TEXAS. TO THE SOUTHWEST OF
THIS PLUME OF ENHANCED LAPSE RATES...A 50 KT MID-LEVEL JET CORE
WAS OBSERVED OVER NORTHERN MEXICO. CLOSER TO THE SURFACE...AT THE
850 MB LEVEL...DEEP MOISTURE WAS ONLY OBSERVED OVER SOUTHWEST
TEXAS WITH A DRYLINE SUBJECTIVELY ANALYZED NEAR THE TX/OK
BORDER...EXTENDING SOUTHWEST OVER WEST CENTRAL TEXAS AND INTO
NORTHERN MEXICO ABOUT 60 MILES WEST OF DEL RIO. A 15Z SURFACE
ANALYSIS OBSERVED RICH MOISTURE IN PLACE ALONG THE TX GULF COAST
WITH MID 70S DEW POINTS OBSERVED WEST AND SOUTHWEST OF HOUSTON.

FOR TODAY...NEARLY ALL SHORT RANGE MODEL GUIDANCE INDICATES THAT A
SURFACE LOW PRESSURE SYSTEM WILL INTENSIFY RAPIDLY THIS AFTERNOON
OVER WEST CENTRAL TEXAS. MOST GUIDANCE SHOWS SURFACE PRESSURE
FALLING AT A RATE OF 2-3 MB PER HOUR LEADING UP TO 00Z. AT
15Z...THE LOWEST SURFACE PRESSURE OVER THE SOUTHERN HIGH PLAINS
WAS AROUND 1002 MB...MOST GUIDANCE INDICATES THE SURFACE LOW'S
PRESSURE WILL FALL TO 993 TO 995 MB BY 00Z. THAT MAGNITUDE OF
PRESSURE FALL ASSOCIATED WITH THE SURFACE LOW IS FAIRLY
INTENSE...AND SHOULD RESULT IN A CONVERGENCE OF PARAMETERS THAT
WILL SUPPORT A LOCALIZED SEVERE WEATHER OUTBREAK ACROSS THE
REGION THIS AFTERNOON AND EVENING. ONE OF THE KEY FORECAST
CHALLENGES TODAY WILL BE DETERMINING WHERE THE SURFACE LOW MOVES
AS THE RELATIVE THREATS FOR SUPERCELLS AND TORNADOES WILL VARY
DEPENDING ON THE EXACT POSITION OF THIS LOW LATER THIS AFTERNOON.

THE 12Z NAM AND 16Z HRRR INDICATE THE SURFACE LOW WILL BE LOCATED
JUST SOUTH OF INTERSTATE 20 AND JUST NORTH OF SAN ANGELO. IF THIS
POSITION FOR THE SURFACE LOW IS CORRECT...THE THREAT FOR DISCRETE
SUPERCELLS WOULD BE MAXIMIZED TO THE EAST OF THE SURFACE
LOW...WHERE A TRIPLE POINT WOULD LIKELY SET UP. SUPERCELLS WOULD
BE MOST LIKELY TO DEVELOP NEAR THIS TRIPLE POINT...AND THEN MOVE
EAST IN THE RELATIVELY STRONG SOUTHWESTERLY FLOW ALOFT. STORMS
APPEAR TO BE VERY LIKELY IN A SUPERCELL STORM MODE IF THEY DEVELOP
IN THIS TRIPLE POINT BY 00Z AS CAPE IS FORECAST TO BE ON THE ORDER
OF 3000 J/KG WITH DEEP LAYER SHEAR OF 50 KTS IN THE 0-6 KM AGL
LAYER. THE SHAPE OF THE 0-3 KM HODOGRAPH IS EXPECTED TO BE
CLOCKWISE LOOPING...AND DYNAMICALLY MORE FAVORABLE FOR RIGHT
MOVING SUPERCELLS. AS A RESULT...EXPECT SUPERCELL STORM MOTION TO
BE ALMOST DUE EAST LATE THIS AFTERNOON AND EARLY THIS EVENING.

RIGHT MOVING SUPERCELLS LOOK MOST LIKELY SOUTH OF INTERSTATE 20
BASED ON THE FORECAST POSITION OF THE SURFACE LOW. THIS PLACES
MUCH OF CENTRAL TEXAS IN THE PRIMARY THREAT CORRIDOR FOR DISCRETE
SUPERCELLS. THE ENVIRONMENT IS SUPPORTIVE OF WELL-ORGANIZED
SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL...DAMAGING WIND
GUSTS AND TORNADOES. THE RESIDENTS OF CENTRAL TEXAS ARE ENCOURAGED
TO PAY VERY CLOSE ATTENTION TO THE WEATHER THIS AFTERNOON AND
EVENING AS A RESULT. OF COURSE IF THE SURFACE LOW IS FARTHER NORTH
...THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS WILL MOVE
NORTH WITH IT. AWAY FROM THIS PRIMARY THREAT CORRIDOR...IT IS
CERTAINLY POSSIBLE FOR SUPERCELLS TO DEVELOP JUST ABOUT ANYWHERE
IN THE WARM AIR ADVECTION REGIME INDICATED BY THE CLOCKWISE
LOOPING LOW-LEVEL HODOGRAPH. THIS LIFT/FORCING IS NOT AS STRONG
AND FOCUSED...SO IT IS SIMPLY MORE DIFFICULT TO KNOW IF...WHEN
AND WHERE A SUPERCELL MAY DEVELOP IN THIS WARM AIR ADVECTION
REGIME.

AFTER 00Z...THE VERY STRONG FORCING FOR ASCENT ASSOCIATED WITH THE
UPPER TROUGH OVER SOUTHERN ARIZONA AND NEW MEXICO IS EXPECTED TO
LIFT OUT OVER THE SOUTHERN PLAINS. THE LATEST MODEL GUIDANCE IS
CONVERGING ON A SOLUTION THAT SUGGESTS A VERY WELL ORGANIZED
SQUALL LINE WILL DEVELOP NEAR CHILDRESS...AND MOVE SOUTHEAST
TOWARDS NORTH TEXAS THIS EVENING. THERE ARE HINTS IN THE MODEL
MASS FIELDS THAT THIS SQUALL LINE COULD POTENTIALLY BE VERY WELL
ORGANIZED...AND MAY POSE A WIDESPREAD DAMAGING WIND THREAT AS IT
MOVES SOUTHEAST ACROSS NORTH TEXAS OVERNIGHT. IF THIS SQUALL LINE
DOES INDEED ORGANIZE...IT MAY PERSIST LONG ENOUGH AND PRODUCE
ENOUGH STRAIGHT LINE WIND DAMAGE TO QUALIFY AS A DERECHO BY THE
TIME IT EXITS THE CWA TO THE EAST WELL AFTER MIDNIGHT. THE PRIMARY
TIME THIS SQUALL LINE/BOW-ECHO IS EXPECTED TO MOVE OVER NORTH
TEXAS IS FROM 10 PM TO 3 AM. THE EXISTENCE OF THIS SQUALL LINE IS
FAR FROM 100 PERCENT CERTAIN...BUT IT WILL PROBABLY ORGANIZE BASED
ON THE CONSISTENT SIGNAL IN THIS MORNING'S HIGH RESOLUTION MODEL
GUIDANCE. THE PRIMARY THREATS WITHIN THIS SQUALL LINE WOULD BE
DAMAGING STRAIGHT LINE WINDS. ASSUMING THE SQUALL LINE MOVES
THROUGH THE AREA AFTER SUNSET AS CURRENTLY FORECAST...THIS MAY
REDUCE THE POTENTIAL FOR HIGH-END DAMAGING WINDS. REGARDLESS...
WIND DAMAGE WOULD STILL BE LIKELY AS THIS SQUALL LIKE WOULD
PROBABLY BE VERY WELL ORGANIZED. LARGE HAIL AND A BRIEF TORNADO
MAY ALSO OCCUR IN THIS LINE...ASSUMING IT DEVELOPS.

LAST BUT NOT LEAST...WE WILL ALSO BE MONITORING FOR HEAVY RAINFALL
AND FLASH FLOODING POTENTIAL THIS AFTERNOON AND EVENING. IF A WARM
FRONT SETS UP ALONG THE INTERSTATE 20 CORRIDOR...SCATTERED
THUNDERSTORMS COULD DEVELOP ALONG THIS BOUNDARY AND TRAIN OVER
AREAS TO THE NORTHEAST. THIS MAY EVOLVE INTO ANOTHER LOCALIZED
FLASH FLOODING EVENT NORTH OF INTERSTATE 20 AND GENERALLY EAST OF
INTERSTATE 35...VERY SIMILAR TO WHAT HAPPENED ON FRIDAY. WILL HOLD
OFF ON A FLASH FLOOD WATCH FOR NOW AS CONFIDENCE IN THIS TAKING
PLACE IS NOT HIGH AT THIS TIME. IF IT OCCURS...THESE LOCATIONS
HAVE ALREADY RECEIVED QUITE A BIT OF RAINFALL ON FRIDAY...SO
FLOODING WOULD TEND TO OCCUR QUICKLY IF STORMS BEGIN TO TRAIN OVER
THIS REGION THROUGH TONIGHT.

WILL CONTINUE TO MAKE SHORT TERM FORECAST UPDATES FOR CONVECTION
MODE THROUGH THIS EVENING. EXPECT STORMS WILL START DEVELOPING
NEAR THE SURFACE LOW AND EVOLVE INTO DISCRETE SUPERCELLS BY/AFTER
4 PM/21Z.

CAVANAUGH

[NTXYankee]

Tornado watch up west of us from OK/TX border south, ours should come along soon, probably higher probabilities which may be why they'll split them up.

[ams30721us]

SPC issues Tornado Watch for areas west of DFW to Waco. They expect that this will not be the only watch of the day.

[bubba hotep]

[bubba hotep]

It looks like a lot of the elevated convection that is firing with this first impulse is getting killed by the dry air located over N. Texas. 

[Roy]

Yikes. I was a tiny boy but still remember the inland hurricane derecho over southern Kansas....widespread 100 mph winds. Doubt anything would be that bad once it made it to the metro though.

[jhamps10]

Yikes. I've seen my share of derachoes living in illinois, they are no fun to deal with...

[NTXYankee]

It looks like a lot of the elevated convection that is firing with this first impulse is getting killed by the dry air located over N. Texas.

Yeah there is some dry air up there and Andy mentioned on the other thread on here that this should help keep moisture from mixing out but also think will help moisten upper levels too. Clearing noted behind this and low still needs to as they said rapidly develop back west. Already humid out and here just east of airport sun goes in and out.