Texas Spring 2017

[cycloneye]

 https://twitter.com/NWSFortWorth/status/847211290019987456

[TarrantWx]

This thing passed just to my south, and then continued on and went directly through my parents' neighborhood. One of their neighbors lost 2 large trees, there was a brick fence that has a section missing, and their pool shed got lifted into the air and one of the doors was damaged. It's all relatively minor damage, but I'm glad that it was only an EF0 and that no one was injured.

[https://twitter.com/NWSFortWorth/status/847211290019987456

[Ntxw]

What came through DFW last night was basically a derecho with very high straight line winds. The tornadoes were spin ups along the line, was quite a line.



Evidence all over today of the rain and high winds with many clean, shiny cars.

[TeamPlayersBlue]

The main cell that tracked through DT Houston and spun up a tornado today tracked to my north. Really didnt have very strong winds at all. My neighborhood is still recovering from the Valentines day tornado that passed through. Some people are just now getting new roofs. 1.15" of rain though was very welcomed.

[JDawg512]

I'm getting pretty irritated with how this next system, which looked for days to be the best rain producer, is becoming yet another disappointment. Its starting to look like the Austin area could miss out on the healthy rain totals. Doesn't look too promising for significant rainfall for the first half of April if you want to believe the GFS.

[Portastorm]

I'm getting pretty irritated with how this next system, which looked for days to be the best rain producer, is becoming yet another disappointment. Its starting to look like the Austin area could miss out on the healthy rain totals. Doesn't look too promising for significant rainfall for the first half of April if you want to believe the GFS.

I would not make that assumption. Opportunities for 1-2" look pretty good per the guidance I have seen.

[wxman57]

I'm getting pretty irritated with how this next system, which looked for days to be the best rain producer, is becoming yet another disappointment. Its starting to look like the Austin area could miss out on the healthy rain totals. Doesn't look too promising for significant rainfall for the first half of April if you want to believe the GFS.

I would not make that assumption. Opportunities for 1-2" look pretty good per the guidance I have seen.

Moisture may be a bit less than with this Sunday's event, but you should get some rain there in Austin. I measured 1.97" yesterday with the passage of that squall line. Some parts of Houston measured 4-5".

Hey, Portastorm! I found some great t-shirts for us. Yours looks cool, but mine is definitely hot!

[JDawg512]

I'll put my faith in you both. As long as at least an inch falls here, I'll be content for another 3 or 4 days before I go back into my rampage for more rain.

[Portastorm]

Love those shirts, wxman57!! We gotta get 'em.

JDawg, I just looked at the 12z Euro and it shows about 1 1/2" for Travis County thru Sunday night. The 0z Euro showed similar. The GFS is bouncing back and forth between 1" and 1 1/2" ... so I feel confident we will see at least as much as what we had this past week and maybe more.

[South Texas Storms]

:uarrow:

Love those shirts, wxman57!! We gotta get 'em.

JDawg, I just looked at the 12z Euro and it shows about 1 1/2" for Travis County thru Sunday night. The 0z Euro showed similar. The GFS is bouncing back and forth between 1" and 1 1/2" ... so I feel confident we will see at least as much as what we had this past week and maybe more.

I agree Porta. The severe threat also looks to be higher with this next system. Models seem to indicate a large MCS developing near the Rio Grande Saturday night and then tracking eastward across the area on Sunday.

[weatherdude1108]

:uarrow:

Love those shirts, wxman57!! We gotta get 'em.

JDawg, I just looked at the 12z Euro and it shows about 1 1/2" for Travis County thru Sunday night. The 0z Euro showed similar. The GFS is bouncing back and forth between 1" and 1 1/2" ... so I feel confident we will see at least as much as what we had this past week and maybe more.

I hope so. Nice to have regular 1"+ rainers. Keeps it pretty and green! It was beautiful outside today, and yesterday! I noticed how clear the air was yesterday after those overnight/early morning storms, compared to the last few weeks. It just felt and looked better. Not sure about rain chances after Sunday night. Maybe a 20% chance next Wednesday, then not sure. Looks like models may be trending on the wet side towards mid April. Still slightly above normal temps. But I just put the rain graphic since that is what counts.

[JDawg512]

:uarrow:

Love those shirts, wxman57!! We gotta get 'em.

JDawg, I just looked at the 12z Euro and it shows about 1 1/2" for Travis County thru Sunday night. The 0z Euro showed similar. The GFS is bouncing back and forth between 1" and 1 1/2" ... so I feel confident we will see at least as much as what we had this past week and maybe more.

I hope so. Nice to have regular 1"+ rainers. Keeps it pretty and green! It was beautiful outside today, and yesterday! I noticed how clear the air was yesterday after those overnight/early morning storms, compared to the last few weeks. It just felt and looked better. Not sure about rain chances after Sunday night. Maybe a 20% chance next Wednesday, then not sure. Looks like models may be trending on the wet side towards mid April. Still slightly above normal temps. But I just put the rain graphic since that is what counts.

I'm loving all that green across much of the state.

[weatherdude1108]

Looks like a chance for wetting rains this weekend, with a chance of strong to severe storms, mainly with an overnight Saturday to Sunday morning MCS/squall line coming in from the Rio Grande.

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
345 PM CDT Thu Mar 30 2017

.SHORT TERM (Tonight through Friday Night)...
A beautiful spring day with sunny skies has settled in across South
Central Texas under northwest flow aloft and weak westerly 5-10 mph
winds and relatively high pressure at the surface. Temperatures have
warmed up into the mid to upper 70s across the region with some lower
80s still anticipated in the Rio Grande Plains and along the I-35
corridor with some weak downsloping effects. Clear skies are expected
tonight, but warm air advection overnight will allow for lows tonight
to be a bit warmer than last night generally in the mid 50s. The
upper level ridge will move through South Central Texas tomorrow,
allowing for clear skies and highs in the mid to upper 80s. However,
some lower 90s expected along the Rio Grande Plains as temperatures
approaching 20 deg/C at 850 mb should mix down dry adiabatically to
the surface. Southerly winds are expected to increase dramatically
tomorrow afternoon to 10-20 mph with stronger gusts to 25-30 mph.
These winds coupled with minimum relative humidities in the lower
20s in the Rio Grande Plains and southern Edwards Plateau and some
teens in Val Verde County will lead to elevated fire weather
conditions in those areas tomorrow afternoon. Low clouds will return
overnight Friday into Saturday morning to keep lows up in the 60s.

&&

.LONG TERM (Saturday through Thursday)...
The main weather impact of the next seven days continues to be this
weekend`s slow-moving storm system that should bring some wetting
rainfall and possibly some severe thunderstorms to the region.
Models generally continue to indicate that the upper level trough
digging south from the Four Corners into the Mexican state of
Chihuahua by Saturday evening will be positively tilted and
relatively slow moving as it weakens. This would suggest that the
potential for more widespread showers and thunderstorms on Saturday
is lower, which model trends generally reflect aside from the GFS.
However, the potential for a shortwave rotating around the broad
trough into south Texas, upper-level divergence associated with a N-S
oriented jet streak to our west, shear values in excess of 40 knots,
and CAPE values in excess of 2000 J/kg continue to suggest the
potential for strong to severe thunderstorms is there for Saturday
afternoon and evening. The biggest question mark will be whether lift
will be focused along a N-S oriented dryline or in a broader area of
NW-SE oriented isentropic ascent. Relatively weak midlevel dynamics
and surface cyclogenesis would favor the latter scenario which
decreases our severe threat somewhat for Saturday afternoon.

Therefore, the most likely scenario at the current moment is for
light streamer showers along the Escarpment Saturday morning with
some scattered strong to marginally severe thunderstorms across most
of the region as the atmosphere destabilizes. We may have a brief
lull Saturday evening before widespread showers and thunderstorms
develop as the surface cold front approaches the region and the
trough to our west finally begins to eject into Coahuila. Some models
suggest storms will develop in the Rio Grande Plains overnight
before merging into a squall line that moves through the region
Sunday morning with the synoptic cold front. Given the shear and
instability present, strong to severe thunderstorms with this line
will be possible. Showers and elevated thunderstorms may last into
Sunday afternoon and early evening as a deepening upper trough that
is becoming more negatively tilted moves through the region before
ending by late Sunday. Rainfall amounts should average around an
inch, but some locally higher totals of 2-3 inches will be possible
particularly along and east of Interstate 35. The greatest threat of
locally heavy rainfall capable of producing flash flooding still
appears to be well east of our area.

Pleasant dry spring weather returns for the first half of next week
as southwest flow aloft returns with highs in the 80s and lows in the
50s and lower 60s. A weak front moving through the region late
Tuesday into Wednesday will cause a slight chance of showers and
thunderstorms over our easternmost counties. Otherwise, the second
half of next week looks dry with cooler temperatures a bit closer to
seasonal normals with highs in the upper 70s to lower 80s.

[Texas Snowman]

@BigJoeBastardi: The El Nino is coming. Very cold SST W Aus leads to higher pressures neg SOI will develop summer into fall. High confidence weak to mod...

@BigJoeBastardi: El Nino does not come on strongly in spring Its summer and fall you will see it. SST w Aus coldest since 1986,1982 el ninos
Telltale sign...

[South Texas Storms]

Here is my latest thinking on this weekend's severe weather and flash flooding risk.

Another potent storm system will move across Texas this weekend bringing the next threat of severe thunderstorms and heavy rainfall to the state. Look for two rounds of storms to possibly impact the area, with the first one developing Saturday afternoon and evening across central Texas. The second and more potent round is forecast to develop along the Rio Grade Saturday night and will then track eastward across much of the state on Sunday. Severe thunderstorms and locally heavy rainfall will be possible, with 1-3 inches of rainfall likely, especially across eastern Texas.

[bubba hotep]

I'm liking the model trends over the past couple of days for this weekend in the DFW area. It then looks like a week or so of nice weather as the Pacific starts to shuffle around a bit and then the storms should kick back up. That will give me some time to finish staining my fence.

[bubba hotep]

Pretty big D3 Enhanced for parts of Texas

[Tireman4]

000
FXUS64 KHGX 311101
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
601 AM CDT Fri Mar 31 2017

.AVIATION [12Z TAF Issuance]...

Mostly straightforward forecast, with most/all sites at VFR
ceilings and visibilities for most/all of their period. Could see
fog or low stratus later tonight, but have only sketched at things
since onset appears to be towards the end of the period as a dry
atmosphere needs to be overcome first.

Beyond cigs/vsbys, southerly onshore flow will establish itself
and become stronger through the day. Eventually think things will
settle in around 10 knots, but gustier in the afternoon. With
sundown, gusts should settle with a bit of a reduction in
sustained winds as well.

Luchs

&&

.PREV DISCUSSION /Issued 444 AM CDT Fri Mar 31 2017/...



.SHORT TERM [Today and Tonight]...

Bodies of water - even small lakes - are clearly visible on IR
satellite late tonight, highlighting the clear skies and light
winds to allow for good radiational cooling. Observations show
that most locations are in the low to mid 60s, with a few rural
spots dropping into the 50s. Conroe is a cool "extreme" at 52.

Expect all but the immediate Gulf coast to slip into the 50s by
morning given dewpoints in the mid 40s to lower 50s. Sunny skies
should prevail most of the day, helping temperatures soar, aided by
warm southerly onshore flow becoming reestablished as surface high
pressure drifts eastward and low pressure begins to form up on the
Texas/New Mexico border.

Low temperatures tonight will be considerably warmer as onshore flow
only continues to fuel a warm, moist profile at the surface. With
dewpoints much higher, may be on the lookout for fog. But, a
tightening pressure gradient should also spur stronger winds, and so
at this time the forecast goes for low stratus instead of fog.

Luchs


.LONG TERM [Saturday Through Friday]...

Sunday...
All I will say about Saturday is to get out and enjoy it. High
temperatures will be in the 80s with moisture return from the
Gulf. Beginning as early as 06Z Sunday through about 00Z Monday,
SE Texas will need to monitor weather closely. SPC has an enhanced
severe weather risk for all of the area on Sunday. WPC has areas
north of a Brenham to Humble line in a slight risk for excessive
rainfall. This means up to a 10 percent chance of exceeding flash
flood guidance. Bottom line being impacts from all weather hazards
may be possible - hail, damaging wind, tornadoes and flooding.

Current water vapor imagery quite clearly shows an upper level
low over the Great Basin into the Desert SW. This system should
reach El Paso by 12Z Sunday. Synopticly this deep trough will
have a strong jet streak moving out of Mexico into Texas during
the day with a vorticity maximum swinging across Mexico into C
Texas by Sunday evening. Large scale lift will be enough to limit
capping from the elevated mixed layer except for maybe south
Texas. A temperature gradient at 850mb may set up from central
Texas northeast towards the Arklatex. It is along this gradient
that both the GFS/ECMWF develop quite a bit of precipitation
meaning areas from Caldwell to Crockett could stand to see heavy
rainfall and flooding potential. These details will likely change
with future model runs but something to monitor with future runs.
There will be about 1.6-1.9 inches of precipitable water, broad
large scale lift from the trough and for good measure 40-50kt LLJ
oriented normal to this 850mb temperature gradient. This
environment very much supports heavy rainfall thus WPC slight risk
of excessive rainfall for areas north of Brenham to Humble.

The environment also is quite favorable for severe weather as
highlighted by SPC`s day 3 outlook. Again these details will
likely change but for now both the GFS/NAM support deep moisture
through the boundary layer. Model soundings for each show moisture
through at least 800mb and surface dewpoints in the upper 60s to
possibly low 70s. Instability is quite high given the set up with
CAPE more than 2000 J/kg mainly due to steep lapse rates (which
would support severe hail). Warm advection and large scale lift
should be enough for surface based convection to form in the warm
sector and even along warm front/850mb temp gradient outlined
above. As for shear, 45-50kts of 0-6km bulk shear and 20-30kts of
0-1km bulk shear should be plenty for organized storms and
possibly supercells. Deep layer shear increases through the day
while low level wind fields veer with approaching dry slot and
Pacific front. Model soundings and SREF probabilities show sig
tor parameters around 3-5 Sunday morning. Tornado threat looks
highest in the morning with hail/wind threat through the
afternoon.

Overall it is hard to find factors that will limit the severe
threat as capping is not that great and strongest to the SW of the
area. The other concern will be if the upper level lift, jet
dynamics and PVA are enough out of phase with moisture/instability
axis that there is not enough lift to initiate convection or erode
what capping there is if any.

Monday Through Friday...
A Pacific front will have pushed through the area Monday morning
with a drier airmass in wake of the front. Southerly winds return
Tuesday bringing back some Gulf moisture, enough to support some
slight rain chances as a cold front pushes through the area
Tuesday night into Wednesday morning. GFS is slower with the front
and holds on to some overrunning precipitation while
ECMWF/Canadian both push the front through quickly. Those models
seem to have a better handle on the short wave trough moving
through the plains mid week than the GFS. An amplified upper level
pattern results for the end of the week and possible to get a re-
enforcing cold front for Friday which may actually keep
temperatures below normal by 2-5 degrees for the first week of
April.


.MARINE...

Moderate winds and seas should develop today and increase
overnight. Conditions should reach caution levels so went ahead
and issued SCEC for all Upper Texas Coastal waters for tonight.
Strong winds may develop Saturday and Saturday night so will need
to monitor for possible advisory conditions. A strong upper level
low will affect Texas over the weekend with showers and
thunderstorms, most of which will be inland. A front associated
with this system will push off the coast Monday morning allowing
for offshore winds. Onshore winds develop again on Tuesday.

Tide levels will need to be monitored Sunday morning into Sunday
afternoon with tides possibly 1-1.5 feet above normal. This will
put tides near 3.5 feet above MLLW late Sunday morning and could
impact Gulf facing beaches. Rip currents will also be a concern.

Overpeck


&&

.PRELIMINARY POINT TEMPS/POPS...

College Station (CLL) 86 63 83 68 78 / 0 0 20 60 80
Houston (IAH) 87 65 84 71 81 / 0 0 10 60 80
Galveston (GLS) 81 71 79 73 77 / 0 10 10 50 80

&&

.HGX WATCHES/WARNINGS/ADVISORIES...

TX...None.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION from this evening through
Saturday morning for the following zones: Coastal waters
from Freeport to the Matagorda Ship Channel out 20
NM...Coastal waters from High Island to Freeport out 20
NM...Galveston Bay...Matagorda Bay...Waters from Freeport
to the Matagorda Ship Channel from 20 to 60 NM...Waters
from High Island to Freeport from 20 to 60 NM.


&&

$$

SHORT TERM...Luchs
LONG TERM...Overpeck
AVIATION...Luchs
MARINE...Overpeck

[bubba hotep]

Here is my latest thinking on this weekend's severe weather and flash flooding risk.

Another potent storm system will move across Texas this weekend bringing the next threat of severe thunderstorms and heavy rainfall to the state. Look for two rounds of storms to possibly impact the area, with the first one developing Saturday afternoon and evening across central Texas. The second and more potent round is forecast to develop along the Rio Grade Saturday night and will then track eastward across much of the state on Sunday. Severe thunderstorms and locally heavy rainfall will be possible, with 1-3 inches of rainfall likely, especially across eastern Texas.

I'm pretty ok with the forecast trend

[1900hurricane]

Lots of question marks for Sunday still, but whoo boy, the 09Z SREF mean is gnarly!