Texas Fall-2015

[Ntxw]

Ntx, if these big Pacific storms come from far enough north, could that result in snow for us in Texas in the fashion of a cold core low? Or would the low need to draw in more arctic air to produce winter weather for us?

If heights are low storms will deepen and draw cold air like 09-10. That was a warm winter up north but we wouldn't know it here. When we say warm up north its not a constant baking, there will be cold periods just their warm days outnumber cold days most likely. The +PDO/-EPO hasn't taken as hard a beating as it did in other big Nino's. Definitely the wild card.

Arctic air is overrated imo . Give me a 540dm bowling ball at 32-35 and I'll take those odds over dry north winds and sheared systems

[Ralph's Weather]

Ntx, if these big Pacific storms come from far enough north, could that result in snow for us in Texas in the fashion of a cold core low? Or would the low need to draw in more arctic air to produce winter weather for us?

If heights are low storms will deepen and draw cold air like 09-10. That was a warm winter up north but we wouldn't know it here. When we say warm up north its not a constant baking, there will be cold periods just their warm days outnumber cold days most likely. The +PDO/-EPO hasn't taken as hard a beating as it did in other big Nino's. Definitely the wild card.

Arctic air is overrated imo . Give me a 540dm bowling ball at 32-35 and I'll take those odds over dry north winds and sheared systems

I am growing more confident in the 09/10 analog, maybe a bit less cold as there is so much warmth to go around but that also means more moisture to work with. this looks to be a year of constant temps in the 40s with 30s under the lows which should be plentiful.

[TeamPlayersBlue]

I looked at the NARR of a storm dec 21 1997. We drove to PHX from Houston that year and ran into a massive ice storm on the way there in West Texas. Well this storm took a very similar path as the one coming this weekend. So noticing this, i guess it is possible. The low just needs to come from a cold region. It didnt snow here in SE Tx but i was curious.

After looking at other analogs, and even looking at the type of systems coming through now, i also like the 09-10 analog too. What i do remember about that year for Houston.....

It was our earliest snow fall ever of Dec 4th. Plenty of strong cold shots, but also had nice warm periods in between to give us a break from the cold. If i remember correctly too, it was fairly cold going into March.

[Brent]

Arctic air is overrated imo . Give me a 540dm bowling ball at 32-35 and I'll take those odds over dry north winds and sheared systems

Agreed completely with this. Growing up in Alabama arctic air was almost always dry and just useless tbh. Every now and then you'd get lucky and get a flizzard but zzzz.

Bowling balls any day. They are called a weatherman's woe by a famous Alabama weatherman.

Oh and don't even tease me with that 09-10 analog.

[weatherdude1108]

I'll take more rain.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
309 PM CDT WED OCT 28 2015

.LONG TERM (FRIDAY THROUGH WEDNESDAY)...
THE FOCUS OF THE LONG TERM IS ON THE UPCOMING UPPER LEVEL STORM
SYSTEM PROGGED TO ENTER THE AREA BEGINNING LATE THURSDAY NIGHT.
LATEST MODELS HAVE BEEN A TAD MORE SLUGGISH ON MOISTENING THE
COLUMN IN THE WEST AS WELL AS STRENGTHENING THE LLJ AND WAA
ENTERING THE RIO GRANDE PLAINS THURSDAY NIGHT. HOWEVER...AFTER
MIDNIGHT...THE LLJ MAGNITUDE AND UPPER LEVEL WIND FIELD INCREASES
RAPIDLY AND WILL RESULT IN A WEST TO EAST DEVELOPMENT OF MODERATE
TO HEAVY RAINFALL WEST OF THE I35 CORRIDOR BY 12Z FRIDAY.

OVER THE COURSE OF THE DAY FRIDAY...THE LLJ AXIS AND UPPER LEVEL
SUPPORT SHIFTS EASTWARD ACROSS THE CENTRAL CWA WHILE SOME MARGINAL
INSTABILITY DEVELOPS INTO THE AFTERNOON. WHILE THE FORECAST
SOUNDINGS CURRENTLY SHOW CAPE AREAS THAT ARE DEEP AND
NARROW...OVERCAST SKIES AND WIDESPREAD RAINFALL SHOULD REALLY
LIMIT BOUNDARY LAYER INSTABILITY. HOWEVER...LOW LEVEL SHEAR SHOULD
BE QUITE STRONG WITH THE STRONG LLJ AND CYCLONIC TURNING IN THE
HODOGRAPH. SRH VALUES ON GFS AND NAM FORECAST SOUNDING IN THE
FIRST 3 KM ARE IN THE 200 RANGE WHICH IS EYE OPENING FOR A LOW
CAPE HIGH SHEAR ENVIRONMENT. THEREFORE...ONLY 500-1000 J/KG OF
CAPE WOULD BE NEEDED WITH SUCH HIGH SHEAR TO RESULT IN THE
POSSIBILITY OF A TORNADO WITHIN THIS AREA OF SHOWERS AND STORMS.

BY FRIDAY EVENING...THE LLJ AXIS SHIFTS TO THE I35 CORRIDOR AND
HEAVY RAINFALL CONTINUES THROUGH THE OVERNIGHT PERIOD. THE COLD
FRONT ASSOCIATED WITH THIS SYSTEM BEGINS TO ENTER THE WESTERNMOST
ZONES BY 00Z SATURDAY. A SECOND ROUND OF HEAVY RAIN MAY BE
ASSOCIATED WITH THE FRONTAL LIFTING OVERNIGHT AS WELL. ALL IN
ALL...THE 48 HOUR QPF TOTALS STILL APPEAR TO BE IN THE 1-3 INCH
RANGE WITH ISOLATED 5 INCHES POSSIBLE...ESPECIALLY FOR THE
SOUTHEASTERN PLATEAU AND I35 CORRIDOR.

THE SYSTEM CLEARS OUT QUICKLY BY MID DAY SATURDAY AS THE FRONT
MOVES THROUGH THE CWA. THE FRONT IS PROGGED TO BE EAST OF THE CWA
BY JUST AFTER 18Z SATURDAY WHICH WILL ALLOW HALLOWEEN NIGHT TO BE
PARTLY CLOUDY AND QUITE NICE FOR TRICK OR TREATING. MIGHT BE A FEW
SHOWERS LINGERING OUT IN THE EXTREME EAST BUT THINK THAT CHANCE
WILL BE VERY LOW.

THE NEXT SYSTEM APPEARS LIKE IT WILL ENTER THE AREA BY DAY 7 BUT
GFS/EURO SOLUTIONS DIFFER IN TIMING SO WILL PASS THESE DETAILS ON
TO LATER SHIFTS.

[Brent]

...CNTRL/S TX...
GOES PW IMAGERY SUGGESTS THAT A MARITIME TROPICAL AIR MASS REMAINS
CONFINED ACROSS THE SWRN GULF BASIN TO FAR S TAMAULIPAS IN ERN
MEXICO. WITH MOISTURE TRANSPORT BECOMING INCREASINGLY PRONOUNCED
DURING THE LATTER HALF OF D1 AS A SLY LLJ STRENGTHENS...ROBUST
LOW-LEVEL WAA/ISENTROPIC LIFT SHOULD AID IN SCATTERED TO WIDESPREAD
CONVECTION FRI MORNING IN A N/S-ORIENTED SWATH ACROSS A LARGE
PORTION OF CNTRL TX. ACTIVITY ALONG THE SRN PERIPHERY SHOULD BE
SURFACE-BASED AMID NEAR 70 DEG F DEWPOINTS. WHILE DOWNSTREAM
DIABATIC HEATING WILL LIKELY BE LIMITED BY ABUNDANT CLOUDS/RAINFALL
AND MOST FORECAST SOUNDINGS SUGGEST WEAKNESSES IN THE 700-500 MB
PORTION OF THE HODOGRAPH...STRONG LOW-LEVEL SHEAR SHOULD SUPPORT
TRANSIENT SUPERCELL STRUCTURES CAPABLE OF A SPORADIC
TORNADO/DAMAGING WIND THREAT. THIS SHOULD PERSIST THROUGH MUCH OF
THE PERIOD WITHIN REGENERATIVE CONVECTION AS THE WARM CONVEYOR
SLOWLY SHIFTS E. WHILE TOTAL SEVERE PROBABILITIES DO NOT APPEAR TO
YET BE AOA 15 PERCENT...AN UPGRADE TO A TORNADO-DRIVEN SLIGHT RISK
SEEMS PLAUSIBLE IN THE D1 TIME FRAME.

[gboudx]

From jeff:

Big chances on the way…Friday and Saturday…rain looks to end before Halloween evening.

Strong upper level storm system is rapidly advancing into the SW US this morning and will move into and across TX Friday and Saturday. Moisture is quickly pooling south of a frontal boundary that crossed the region yesterday along the lower TX coast and will rapidly advance northward late this afternoon and tonight. Dewpoints currently in the 40’s and 50’s will rise into the upper 60’s on Friday and near 70 or greater Friday night. Surface low pressure developing over the Pecos valley region of TX will force a strong low level jet by early Friday over the coastal bend into SE TX with strong south winds likely…wind advisories may be needed on Friday. Warm air advection regime will likely begin to produce enough lift to generate a few showers and even thunderstorms by early to mid afternoon Friday across our western counties with this activity spreading eastward during the evening hours. Might see an isolated strong storm with this development.

Friday night-Saturday midday:
Strong lift and dynamics come to bear across a very moist air mass with PWS surging to 2.0-2.2 inches. As the surface low moves NE across the state backed low level winds will increase shear values Friday night. While this would normally yield an increased tornado threat, a general lack of instability should help to moderate the strong shear values. However the tropical nature of the air mass and high shear environment could certainly produce a few low topped supercells with quick short lived tornadoes…not much different from last weekend.

Convective nature of the event will result in high short term rainfall rates of 1-3 inches per hour. Meso models do suggest a couple of line segments over SE TX Saturday morning that may want to slow and train for a period of time, but overall progressive nature of the event should preclude a widespread flash flood threat. Localized flooding will be possible especially in urban areas.

Saturday evening:
Storm system will exit to the east Saturday afternoon and evening with rainfall ending. Most of the rainfall will likely be over and done by sunset, but cannot rule out an isolated lingering showers. Temperatures will cool into the low to mid 60’s with light NW winds.

Hydro:
Significant flood wave generated on the Trinity River from the 15-20 inches of rainfall last week around Corsicana is moving downstream toward Lake Livingston. Upstream flood control operations on Richland Chambers Reservoir continue. Richland Chambers set a new record discharge this past weekend of over 140,000 cfs being released (60,000 cfs was the old record). Lake Livingston has begun flood gate operations to attempt to draw down the full pool level of the lake prior to the flood wave entering Livingston this weekend. Based on current upstream flows and with the expected additional rainfall this weekend it is certain that the river below Livingston will go into flood and likely major flood at Liberty. This will likely be an extended flood for the lower Trinity basin given the amount of upstream run-off moving downstream and the continued wet forecast.

Tides:
Lunar tides are running high and will continue to run high into this weekend. After the “great blow out” Sunday when the water level in the NW part of Galveston bay dropped over 4.0 ft in 24 hours…water levels have been increasing since then and are now running about 1 ft above normal. Strong southerly winds on Friday will add a little more water pushing levels to near 1.5 ft, but a southerly wind is not as favorable coastal flood wind for us as an easterly wind.

Long Term:
Another storm system will move toward TX around the middle of next week with additional rainfall likely.

[Ntxw]

We can tell our kids and grandkids later down the road we lived through 2015 the year of the flash weather.

From This



To this



Back to this



Cleared up again towards this



And by this time next week a lot of that will be gone


People write articles about this stuff decades later

***Note if you're going to quote remember to remove IMG tags

[Ntxw]

Interesting set up the next 2 days. Mesoscale features will play an even more important role and low level jet. Models show a modest 1-3 inches around DFW but 2-4+ on either side. Small scale shifts can greatly move things around.

[CaptinCrunch]

NWS FTW, this pretty much sums up what NTXW was saying above....

FRIDAY EVENING THROUGH EARLY SATURDAY MORNING...MODEL OUTPUT QPF
CONTINUES TO HIGHLIGHT LOCATIONS ALONG AND WEST OF THE I-35/I-35W
CORRIDOR AS HAVING THE BEST CHANCES AT SEEING HEAVY RAINFALL AND
POTENTIALLY FLOODING AT THIS TIME. HOWEVER...NOW THAT WE`RE
GETTING CLOSER TO THIS EVENT...MESOSCALE MODELS AND A MUCH FINER
RESOLUTION OUTPUT IS STARTING TO HIGHLIGHT SOME OF THE COMPLEXITY
OF THIS EVENT. HERE`S A SUMMARY OF WHAT`S LIKELY TO UNFOLD:

1. THE BEST LARGE SCALE DYNAMICS FOR LIFT SEEM TO SET UP ALONG AND
WEST OF I-35. UNDOUBTEDLY THIS IS WHY THE LARGER SCALE MODELS
/GFS/ECMWF/ HIGHLIGHT THIS AREA AS HAVING THE BEST POTENTIAL FOR
HEAVY RAINFALL. IT MAKES SENSE. AFTER SUNSET A STRONG LOW-LEVEL
JET DEVELOPS OVER THE REGION WITH STRONG CONVERGENCE INDICATED
FROM THE RED RIVER...ARCING SOUTH WEST OF I-35. UPPER LEVEL LIFT
FROM THE TROUGH (DPVA) SPREADS EAST OVER THIS SAME AREA AT THAT
TIME. LASTLY...THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET
STREAK SETS UP OVER THAT SAME AREA. THE AGEOSTROPHIC RESPONSE TO
THIS AREA OF DIVERGENCE ALOFT WILL ONLY HELP SUPPORT LARGE SCALE
LIFT OVER THE REGION. AS A RESULT OF ALL OF THESE FACTORS... THIS
IS STILL THE MOST LIKELY AREA TO RECEIVE HEAVY RAINFALL DURING
THIS EVENT.

2. THE MESOSCALE ENVIRONMENT CAN DOMINATE THE LARGER SCALE
FORCINGS HIGHLIGHTED ABOVE (SYNOPTIC SCALE) AND DISPLACE THE AREA
OF HEAVIEST RAINFALL. THE 4-KM NAM AND NMM AND ARW CORE WRF MODELS
HIGHLIGHT THIS POSSIBILITY. THESE MODELS...WHILE NOT IDENTICAL IN
SOLUTION...INDICATE THAT A COUPLE OF SQUALL LINES MAY DEVELOP
AROUND SUNSET FRIDAY EVENING. IF A COUPLE OF MCS STRUCTURES
DEVELOP AND ARE WELL ORGANIZED...THESE SYSTEMS CAN SHUNT THE AREA
OF HEAVIEST RAINFALL AWAY FROM WHERE THE SYNOPTIC SCALE FORCING IS
MAXIMIZED. THIS DISPLACEMENT BY ORGANIZED MESOSCALE SYSTEMS IS
TYPICALLY INTO THE DIRECTION OF THE LOW-LEVEL JET...SO DISPLACED
SOUTH-SOUTH EAST IN THIS CASE. IF ONE OR TWO WELL ORGANIZED MCSS
DEVELOP...THE HEAVIEST RAINFALL AXIS COULD SHIFT SOUTH-SOUTHEAST
TOWARDS THE HILL COUNTRY AND ACROSS PARTS OF CENTRAL TEXAS.

AT THIS TIME...CONFIDENCE IS TOO LOW TO SIDE WITH EITHER ONE OF
THESE SOLUTIONS. IF HIGHER RESOLUTION MODEL GUIDANCE DEVELOPS A
CONSENSUS WITH REGARDS TO MCS PLACEMENT...THIS SOLUTION WILL BE
MORE LIKELY TO VERIFY. HOWEVER...THE MAIN LIMITING FACTOR LIMITING
THE POTENTIAL FOR A WELL ORGANIZED MCS TO DEVELOP IS THE POTENTIAL
FOR FREE CONVECTION. ALL MODELS HAVE A STRONG LOW-LEVEL JET ACROSS
THE REGION DURING THIS TIME OF CONCERN...SO THE KINEMATICS ARE
CERTAINLY PRESENT FOR AN ORGANIZED THUNDERSTORM COMPLEX. HOWEVER
FORECAST SOUNDINGS ACROSS THE REGION INDICATE A THERMODYNAMIC
ENVIRONMENT CHARACTERIZED BY DEEP MOIST ADIABATIC LAPSE RATES.
THIS WOULD SEEM TO LIMIT THE STRENGTH OF THUNDERSTORM GENERATED
COLD POOLS WHICH ARE VERY IMPORTANT IN TERMS OF THE ORGANIZATION
AND MAINTENANCE OF MCS STRUCTURES.

AS A RESULT...WILL CONTINUE TO HIGHLIGHT AREAS ALONG AND WEST OF
I-35 AS HAVING THE BEST POTENTIAL FOR HEAVY RAINFALL AND
FLOODING...KEEPING IN MIND THAT THIS MAY END UP DISPLACED SOUTH-
SOUTHEAST IF WE LOOK TO HAVE MORE CAPE AVAILABLE THAN CURRENTLY
FORECAST. WILL CONTINUE TO ADVERTISE 1-3 INCHES OF RAIN POSSIBLE
FOR JUST ABOUT ANYWHERE ACROSS NORTH CENTRAL TEXAS...WITH A
FOCUSED AXIS OF 2-4 INCHES AND LOCALLY HIGHER AMOUNTS DEPENDENT ON
WHICH SOLUTION (1 OR 2 ABOVE) PANS OUT. WILL HOLD OFF ON A FLASH
FLOOD WATCH UNTIL CONFIDENCE IS HIGHER ON WHERE THE AXIS OF
HEAVIEST RAINFALL WILL PAN OUT.

HALLOWEEN AND SUNDAY...MODELS CONTINUE TO BE AGGRESSIVE WITH A
MID-UPPER LEVEL DRY SLOT OVER THE REGION AS EARLY AS SATURDAY
MORNING. THIS SHOULD CAUSE PRECIPITATION TO END FROM WEST TO EAST
THROUGHOUT THE DAY ON SATURDAY...WITH MOST LOCATIONS REMAINING DRY
FOR HALLOWEEN EVENING. DRY WEATHER IS EXPECTED TO CONTINUE ON
SUNDAY AS LARGE SCALE SUBSIDENCE SPREADS OVER THE REGION FROM WEST
TO EAST.

NEXT WEEK...DRY AND WARM WEATHER IS EXPECTED TO START THE WEEK
OFF...WITH ANOTHER STORM SYSTEM AFFECTING THE AREA BY MID-WEEK.
KEPT POPS BROAD BRUSHED AND IN THE 30 TO 40 PERCENT RANGE NOW
UNTIL MORE DETAILS REGARDING THIS STORM SYSTEM`S TIMING AND
STRENGTH CAN BE RESOLVED.

CAVANAUGH

[weatherdude1108]

Ugh. This is more like Spring. At least Halloween will be okay for the trick or treaters.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
304 PM CDT THU OCT 29 2015

TXZ171>173-183>194-202>209-217>225-228-301200-
LLANO-BURNET-WILLIAMSON-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-
GILLESPIE-KENDALL-BLANCO-HAYS-TRAVIS-BASTROP-LEE-KINNEY-UVALDE-
MEDINA-BEXAR-COMAL-GUADALUPE-CALDWELL-FAYETTE-MAVERICK-ZAVALA-
FRIO-ATASCOSA-WILSON-KARNES-GONZALES-DE WITT-LAVACA-DIMMIT-
INCLUDING THE CITIES OF...LLANO...BURNET...GEORGETOWN...DEL RIO...
ROCKSPRINGS...LEAKEY...KERRVILLE...BANDERA...FREDERICKSBURG...
BOERNE...BLANCO...SAN MARCOS...AUSTIN...BASTROP...GIDDINGS...
BRACKETTVILLE...UVALDE...HONDO...SAN ANTONIO...NEW BRAUNFELS...
SEGUIN...LOCKHART...LA GRANGE...EAGLE PASS...CRYSTAL CITY...
PEARSALL...PLEASANTON...FLORESVILLE...KARNES CITY...GONZALES...
CUERO...HALLETTSVILLE...CARRIZO SPRINGS
304 PM CDT THU OCT 29 2015

...APPROACHING STORM SYSTEM TONIGHT WILL BRING LOCALLY HEAVY
RAINFALL AND ISOLATED STRONG TO SEVERE THUNDERSTORMS THROUGH EARLY
SATURDAY MORNING...

SHOWERS AND STORMS ARE EXPECTED TO DEVELOP OVER THE BIG BEND AND
RIO GRANDE PLAINS AREA LATE TONIGHT AND SPREAD EASTWARD THROUGH
THE NIGHT REACHING THE INTERSTATE 35 CORRIDOR BY AROUND DAYBREAK
FRIDAY MORNING. LOCALLY HEAVY RAINFALL IS THE MAIN
CONCERN...ESPECIALLY IN AREAS THAT RECEIVED MULTIPLE INCHES OF
RAIN IN LAST WEEKENDS RAIN EVENT. IF ANY PERSISTENT HEAVY RAIN
AREAS DEVELOP FRIDAY...THEY COULD RESULT IN LOCALIZED FLASH
FLOODING.

THERE ALSO EXISTS A LOW BUT NON-ZERO TORNADO THREAT IN ADDITION TO
DAMAGING WIND AND SMALL HAIL DURING THE DAY ON FRIDAY...AS
TEMPERATURES SLOWLY WARM THROUGHOUT THE DAY. IN THIS KIND OF SET
UP...IF TORNADOES WERE TO DEVELOP...THEY WOULD LIKELY BE SHORT
LIVED AND WEAK. THE TORNADO THREAT IS EXPECTED TO DIMINISH BY
NIGHTFALL RESULTING IN A LINE OF STORMS MOVING EAST ACROSS THE
AREA INTO THE LATE FRIDAY EVENING HOURS AND INTO EARLY SATURDAY
MORNING. THE THREAT WITH THIS LINE WILL PRIMARILY BE STRAIGHT LINE
WINDS AND HEAVY RAINFALL. THOSE WITH OUTDOOR PLANS FRIDAY AND
FRIDAY NIGHT ARE URGED TO BE ALERT FOR THE POTENTIAL FOR LIGHTNING
AND HAVE A WAY TO RECEIVE WEATHER WARNINGS.

FOR THOSE CONCERNED WITH OUTDOOR ACTIVITIES ON HALLOWEEN...
EXPECTATIONS ARE THAT THE SYSTEM WILL BE WELL EAST OF THE AREA BY
MID DAY SATURDAY LEAVING THE AFTERNOON AND EVENING HOURS SAFE FOR
TRICK OR TREATING. HOWEVER...UNTIL THEN...IT IS IMPORTANT TO STAY
WEATHER AWARE AND HEED WHATEVER WARNINGS ARE ISSUED OVER THE NEXT
COUPLE DAYS

[Ntxw]

12z euro shafts north and northeast Texas about an inch. Axis of 2-5+ inches of rain in central, NW, and northern parts of SE Texas

[dhweather]

12z euro shafts north and northeast Texas about an inch. Axis of 2-5+ inches of rain in central, NW, and northern parts of SE Texas

If we just get 1-2" - I'm good.

[gboudx]

Me too. The ground is still soaked and wet to walk on. I shut my sprinklers off for the Winter. Time for grass to die anyway.

[opticsguy]

Just planted cover crops and fertilized the lawn. An inch of rain would be perfect.

I'd rather the watersheds of the big lakes get the 6" rains.

[Brent]

With the models hinting at a multi-day rain setup mid/late next week... I'd be happy with an inch or so. Much more to come...

[Ntxw]

Yeah the pattern is quite active. Especially since the country will be warm, that makes rainfall more believable vs a cold pattern.

Speaking of warm, it will be close for DFW to make top 10 warmest Octobers. Surprisingly the closest year (warm Sept/Oct and going into warm November) with an El Nino is 1963. That year was drier though.

I'll take 1963, one of the big 3 years.

[Brent]

DFW only needs 1.87" for 2nd wettest October

and I never even noticed 1963 was the warmest October on record and I've looked at that October climo so much lately.

[Ntxw]

DFW only needs 1.87" for 2nd wettest October

and I never even noticed 1963 was the warmest October on record and I've looked at that October climo so much lately.

I'll take a 1963 redux even if it means a warm November. Who doesn't want a foot of snow and single digits?! With 60+ freezes

[gboudx]

Who doesn't want a foot of snow and single digits?! With 60+ freezes

There's a Cajun guy who rides a bike in the Houston area that might not enjoy it.