JUNE 2016: Showers/Storms Possible

[jasons2k]

Drove back from Austin yesterday. The Brazos was still raging.

We also witnessed the cattle rescue on 290 @ the Brazos river last Friday, right in front of us. Held us up for about 45 minutes before 290 was re-opened...

We need to keep a close watch this week. The ULL may stall and transition to a warm-core low. We all know what that means in early June....

[DoctorMu]

After this week, is this pattern finally going to shift to normal sunny Summer weather? Two springs in a row that have been absolutely awful

Be careful what you wish for. Last year, the spigot shut off on July 4. Barely a trace of rain until October 22. Foliage around here is still recovering from the summer of 2011.

[jasons2k]

After this week, is this pattern finally going to shift to normal sunny Summer weather? Two springs in a row that have been absolutely awful

Be careful what you wish for. Last year, the spigot shut off on July 4. Barely a trace of rain until October 22. Foliage around here is still recovering from the summer of 2011.

This is true. Even though 2015 was officially a 'wet' year, that mini-drought destroyed the little forward progress the trees had made. A lot of them relapsed. It will take a long period of un-disturbed wetness for them to fully recover from the stress.

[srainhoutx]

First in likely a series of Flash Flood Watches have been hoisted for the Hill Country, San Angelo Area and the Western portion of the Fort Worth/Dallas area...


URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1052 AM CDT TUE MAY 31 2016

...FLASH FLOOD WATCH IN EFFECT FOR ALL OF SOUTH CENTRAL TEXAS
THROUGH THURSDAY MORNING...

.THERE WILL BE A CHANCE FOR MULTIPLE PERIODS OF HEAVY RAINFALL
FROM TUESDAY AFTERNOON THROUGH AT LEAST THURSDAY MORNING.
WIDESPREAD RAINFALL TOTALS ARE FORECAST BETWEEN 3 TO 6 INCHES WITH
SOME LOCATIONS POTENTIALLY SEEING AS MUCH AS 10 INCHES. IN
ADDITION TO THE HEAVY RAINFALL POTENTIAL...MANY AREAS HAVE SEEN
MULTIPLE INCHES OF RAINFALL OVER THE PAST WEEK RESULTING IN
SATURATED SOILS UNABLE TO ABSORB MUCH MORE RAINFALL. THUS...HEAVY
RAINFALL WILL LIKELY RESULT IN RAPID DEVELOPMENT OF FLASH FLOODING
IN THE MOST VULNERABLE AREAS. ALSO...MULTIPLE AREA RIVERS AND
STREAMS ARE ELEVATED...SO FLASHY RIVER RISES WILL ALSO BE POSSIBLE
DURING THE NEXT FEW DAYS.

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...
BRACKETVILLE...UVALDE...HONDO...SAN ANTONIO...NEW BRAUNFELS...
SEGUIN...LOCKHART...LA GRANGE...EAGLE PASS...CRYSTAL CITY...
PEARSALL...PLEASANTON...FLORESVILLE...KARNES CITY...GONZALES...
CUERO...HALLETSVILLE...CARRIZO SPRINGS
1052 AM CDT TUE MAY 31 2016

...FLASH FLOOD WATCH IN EFFECT THROUGH THURSDAY MORNING...

THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WATCH FOR A PORTION OF SOUTH CENTRAL TEXAS...
INCLUDING THE FOLLOWING AREAS...ATASCOSA...BANDERA...BASTROP...
BEXAR...BLANCO...BURNET...CALDWELL...COMAL...DE WITT...
DIMMIT...EDWARDS...FAYETTE...FRIO...GILLESPIE...GONZALES...
GUADALUPE...HAYS...KARNES...KENDALL...KERR...KINNEY...LAVACA...
LEE...LLANO...MAVERICK...MEDINA...REAL...TRAVIS...UVALDE...
VAL VERDE...WILLIAMSON...WILSON AND ZAVALA.

* THROUGH THURSDAY MORNING

* WIDESPREAD RAINFALL TOTALS OF 3 TO 6 INCHES WITH SOME LOCATIONS
REACHING AS HIGH AS 10 INCHES. ALSO...VERY SATURATED SOILS WILL
FURTHER ENHANCE THE POSSIBILITY FOR FLASH FLOODING AND INCREASE
THE LIKELIHOOD OF RAPID FLOODING.

* RIVERS AND CREEKS ARE SWOLLEN AND ANY ADDITIONAL RAINFALL WILL
WORSEN THE CONDITIONS. SOILS ARE EXTREMELY SATURATED AND ANY
ADDITIONAL RAINS WILL LIKELY RESULT IN RAPID RUN OFF AND
ACCUMULATION OF FLOOD WATERS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION.

YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION
SHOULD FLASH FLOOD WARNINGS BE ISSUED.

[Rip76]

Don't know much about Michael Ventrice, but....

From his Twitter page.

"Roughly a 10-30% for a developing tropical cyclone over the Gulf of Mexico this week. Not a big signal out of ECMWF."

[BiggieSmalls]

After this week, is this pattern finally going to shift to normal sunny Summer weather? Two springs in a row that have been absolutely awful

Be careful what you wish for. Last year, the spigot shut off on July 4. Barely a trace of rain until October 22. Foliage around here is still recovering from the summer of 2011.

This is true. Even though 2015 was officially a 'wet' year, that mini-drought destroyed the little forward progress the trees had made. A lot of them relapsed. It will take a long period of un-disturbed wetness for them to fully recover from the stress.

A typical Texas summer is hot and dry..trees or not, I don't feel bad for saying I hope things are "normal" this summer. We don't live in Florida for a reason. Bring on the pool/lake weather!

[srainhoutx]

Don't know much about Michael Ventrice, but....

From his Twitter page.

"Roughly a 10-30% for a developing tropical cyclone over the Gulf of Mexico this week. Not a big signal out of ECMWF."

The models have been 'sniffing' the potential of some sort of tropical development mostly associated with the monsoonal trough as well as the MJO becoming more favorable and a rather wet Convectively Couple Kelvin Wave approach from the Eastern Pacific. Those features likely assisted in the organization of a tropical disturbance (91E) in the Eastern Pacific.

[jasons2k]

Well, we moved from Dallas to The Woodlands to live amongst the trees instead of the endless concrete prarie grid, so I don't feel bad asking for a drought-free summer. Normal is OK, which usually means sea-breeze relief along the coast, not 3 months of no rain.

[mcheer23]

I expect HGX to issue FFW by tomorrow.

[Rip76]

Starting to fire up - right on time.

[srainhoutx]

Shorter fuse quantitative precipitation forecast suggest possibly 6+ inches mainly near the Edwards Plateau, San Antonio, Hill Country area with some increase across portions of SE Texas.

[don]

Theres a slight disagreement between the GFS and Euro/Canadian models. The GFS has most of the rain falling across the central portions of the state,while the Canadian and Euro models have the heavy precipitation more widespread,which both the Euro and Canadian models bring in multiple slow moving squall lines/storm complexes into Southeast Texas over the next few days.

[srainhoutx]

The Weather Prediction Center updated Day 2 and 3 Excessive Rainfall Outlooks inching closer. Worrisome to already see a Moderate Risk across the Hill Country into S Central Texas. The Slight Risk has expanded East to include SE Texas.

[srainhoutx]

Forecaster Scott Overpeck of NWS Houston/Galveston issues a great Area Forecast Discussion explaining exactly why we have been very concerned regarding the potential of yet another heavy rainfall event. It is well worth reading and explains the complicated and complex forecast ahead. Stay tuned folks. With so many of our neighbors already suffering and at least 8 confirmed deaths from the Flood of last Thursday and Friday, we will continue to Update very regularly.

Area Forecast Discussion
National Weather Service Houston/Galveston TX
402 PM CDT TUE MAY 31 2016

.DISCUSSION...
Water vapor imagery shows a short wave trough moving into Texas
which has allowed for widespread thunderstorm activity from the NW
Hill Country through central Texas. This thunderstorm activity was
producing very heavy rainfall in central Texas as it was located
within an axis of higher moisture running from south Texas through
north central Texas. Some of these storms have produced 2 inches
of rain in an hour. Short range hi-res model guidance shows some
of this activity possibly reaching the Brazos Valley later this
evening before dissipating. The forecast will keep 30-40 percent
chances of thunderstorms in the forecast. The main concerns will
be heavy rainfall but moderate instability may allow for a
strong/severe storm with hail/downburst wind threat.

Day 2-5...Wednesday to Saturday...
This will be the critical time frame for a heavy rainfall threat
over SE Texas. There is overall high confidence that there will be
rainfall during this time frame across the area but low confidence
in where exactly higher rainfall amounts will occur. An upper
level low over the Desert SW and NW Mexico will move across the
southern Rockies into Texas by Thursday into Friday. This upper
level low will be slow moving across the state and likely stall
over the Texas Gulf coast and SE Texas on Saturday. An upper
level trough over the upper Midwest will drop into the Ohio River
Valley on Sunday. This will help shear out the upper low over the
Gulf Coast for the weekend. With this NW flow aloft, believe it or
not, there will actually be a weak front that pushes through into
the Gulf Sunday into Monday. Still some uncertainty as to if this
front actually pushes through but noteworthy nonetheless.

This means that Wednesday through Friday the upper level pattern
will be very conducive for heavy rainfall. With the upper level
low moving towards the area slowly, upper level winds should
decrease and then allow for slow storm motions of under 20 knots.
Precipitable water values will range from 1.8 to 2.0 inches during
this time. There will also be good inflow from the Gulf with 850mb
winds of 20 to 30 knots supporting precipitable water values
around 2 inches for Thursday/Friday. By Sunday precipitable water
values should be decreasing with possible front passage and likely
bring an end to rain chances for early next week. Jet stream flow
will become increasingly diffluent and divergent over much of the
area which would limit any capping and increase large scale ascent
over the region. A frontal boundary pushing into north Texas
tonight may not play much of a role in focusing convection for SE
Texas but could be where surface low pressure forms along in
response to the upper level low moving across Texas. This boundary
may contribute to heavy rainfall over central Texas tomorrow and
Thursday. Rainfall amounts will be tough to nail down but looking
at 2 to 4 inches of rain for the whole area for the next 5 days.
The problem will be identifying areas that may be susceptible to
isolate higher amounts. This is where the mesoscale evolution is
critical but also involves the most non-linearity. Basically
mesoscale processes introduce quite a bit of uncertainty in the
forecast and where the 2 to 4 inches of rainfall become 6 to 8
inches rather quickly especially if higher rain rates can be
achieved. Mesoscale QPF forecasting will be the main problem as
evidenced by recent heavy rainfall/flood events. Flash flood watch
will likely be needed but will wait to see how the atmosphere
evolves the next 24 to 36 hours. Watch may be issued sometime
tomorrow likely for the Thursday/Friday time frame.
Overpeck

[unome]

Hope Floats http://www.cpc.ncep.noaa.gov/products/p ... ns/610day/

[houstonia]

11:00 update from Jeff:

***Significant flash flood and river flood threat across TX***

***Potentially dangerous flash flood event for TX next several days***

Hydro situation across this state is dire and additional potentially excessive rainfall is going to push area river systems and lakes to beyond their breaking point. The systems are just overloaded and given what has transpired this afternoon across the Hill Country (4-6 inches of rainfall) flooding is almost ineveitable across this state over the next 5 days.

I am extremely concerned with the potential of this system to drop copious rainfall leading to devastating flooding.

Discussion:
Upper level system will move into TX on Wednesday and park over the state for the next 5 days. Very high tropical moisture levels will surround this upper level feature and there is the increasing potential for this system to begin to take on tropical warm core charateristics which is deeply concerning. Such slow moving systems in the past across this state in the warm season summer months have produced devastating flood events even with dry conditions before onset. Warm core systems generally like to focus extreme rainfall near their circulation cores during the overnight hours and these rains can be extraordinary…TS Allison…TS Charley…TS Frances. Such systems have produced some of the greatest floods this state has ever experienced.

Expect numerous rounds of thunderstorms to onset by Wednesday afternoon. Storm motions really begin to slow down into Wednesday night through Friday with less than 20kts of forward motion. 850mb inflow of 20-30kts is really favorable for providing a rich low level flow of moisture…combine that with strong and near continuous upper level divergence and you have another classic flash flood setup over this state.

Will go with widespread rainfall amounts of 2-4 inches through Friday…but am almost certain there is going to be significantly higher amounts. Confidence is poor to where these large totals may occur…but right now will favor areas W of I-45 and N of I-10, or the area that has been devastated over the last 6 weeks with flooding. This also highly impacts the Brazos and Colorado basins which are already dealing with devastating flooding. Think storm totals of 10-15 inches are certainly possible in isolated locations especially over our western counties into central TX. Where such rainfall occurs on already very saturated grounds will result in catastrophic flooding. There is just no skill at this range of predicting where these really big totals may occur.

Residents across the entire region should be prepared for significant flash flooding and watershed flooding over the next 5 days. React immediately to rising water and expect flooded roadways. Never drive into high water…let me say this again NEVER DRIVE INTO HIGH WATER!!!

Brazos River:

Brazos River has risen past the expected forecast today of 53.5 ft and is currently at 54.3 ft this evening and still rising which is smashing the old 1994 record. Flooding across Fort Bend into Brazoria County is devastating. Water is against all the levees in Fort Bend County and back water flooding is starting to cut-off some subdivisions. Large sections of Fort Bend County are flooded with water in parts of Rosenberg and Valley Lodge many feet deep in homes. The river is across the basin divide into Oyster Creek. This situation is Fort Bend and Brazoria Counties moving forward is dire with additional heavy rainfall forecast. Levee protected subdivisions will have to pump additional rainfall as gravity flow into the river is not possible at this time due to the very high levels which could lead to flooding within these subdivisions if rainfall rates exceed to pumping capabilities.

[Andrew]

GFS and ECMWF are in pretty good consensus that through the next 5 days most areas should see at least 2-4 inches of rain. The key here is the higher totals. Global and mesoscale models indicate that training will be possible everyday of the week from here on out as storms rotate around the mid level low that will stall over the state. For instance, if going by the ECMWF verbatim, 6-8 inches could occur just to the Northwest of Harris County. The GFS thinks that will occur further north across central and northern Texas. So overall expect a widespreasd 2-4 inches but some areas will probably at least double that over the next couple days. Looking at the HRRR and SPC mesoanalysis, it is a little concerning to see a surface boundary currently setup over SE Texas. This could help focus storms as we head into the afternoon.

[srainhoutx]

As Jeff mentioned in his update above, should the transition to a warm core system occur, devastating flooding could become a real possibility. The overnight guidance continues to struggle with the evolution of the upcoming sensible weather pattern over the next 5 to 7 days. A new fly in the ointment is yet another upper low moving across Southern California this weekend and the potential of some tropical mischief moving out of the NW Caribbean Sea into the Southern Gulf associated with a monsoonal trough of low pressure enhanced by a favorable MJO pulse and a robust Convectively Coupled Kelvin Wave meaning rising air that aids in the development of tropical thunderstorms. The morning updated quantitative precipitation forecast may be too optimistic regarding the precipitation amounts. With our Rivers, watersheds and Lakes filled to capacity, will err on the side of extreme caution since so many of our neighbors are suffering. Fingers crossed the flooding does not materialize and we escape with minimal effects.

[srainhoutx]

The morning Area Forecast Discussion advertises what we have been watching and discussing since the Memorial Day Holiday Weekend. Please take time to read the information provided by our National Weather Service Office in SE Texas. It explains the possibilities of this very complex and complicated forecast and why we have been very concerned with the possibility of another heavy rainfall event for our Region.


Area Forecast Discussion
National Weather Service Houston/Galveston TX
456 AM CDT WED JUN 1 2016

.DISCUSSION...
Southeastern Texas is readying itself for another few days of
precipitation brought on by periods of locally moderate to heavy
rainfall that will likely induce or aggravate regional flash and
river flooding. All of the synoptic ingredients are in place, from
the gradual spreading of the upper levels as jet level winds become
more diffulent just ahead of the southwestern-settling mid to upper
low to the stout lower to mid level southeasterly 20-35 knot inflow
feeding inland convection with near 2 inch precipitable waters.
The devil is in the details as they say and this couldn`t be more
true of a idiom than for us over the next several days. Yes,
confidence is mounting that many across the region will experience
a round or three of impressive rainfall (rates) that will again
produce flooding and quite possibly various communities will be
dealing with wind damage from either localized wet downbursts or
weak tornadoes from passing strong thunderstorm clusters. As is
the case with all of these anticipated potential severe weather
events...the question of the exact timing and location of the most
intense weather will go unanswered until either right before its
passage or during the heat of battle itself. Although the vicinity
(unfortunately southwestern-positioned) upper low and subsequent
shortwave disturbances rotating around this main feature will
ultimately be the impetus to inclement weather, it will be the
mesoscale that determines the when and the where of the most
severe rainfall and wind. Or, in other words, it will be that
prior convection that drives future convective behavior and, if we
can better pinpoint this on a 6 hour time line, then we may be
able to more accurately convey a relatively higher confidence with
a 12,or even 24, hour forecast.

The target days for the highest rainfall will be from as early as
today through as late as Saturday afternoon. This is the period in
which the upper low currently digging down over the lower U.S.
Southwest and the northern Mexico Providences of Sonora and
Chihuahua will nestle itself over Texas, particularly over eastern
or south central state. With the highly moist `condition`ally
unstable air mass already in place over the region, this scenario
is the worse possible for us as it places eastern Texas under the
best upper exhaust pattern for series of disturbances (the `conditional`)
to generate lift and maintain an environment conducive to the
formation of continual clusters of thunderstorms to slowly travel
(train) over the area. Not expecting overall storm motion to be
all that fast within a forecast weakly steered lower layer. As of
now, the forecast calls for likely rain/storm chances commencing
today and persisting through the weekend. There will be periods of
either very light or no precipitation, especially if an MCS travels
across the CWA and creates subsidence in its wake. A model and
national center blend equates to an areawide 5 day QPF of between
4 to 5 inches, locally higher with amounts of greater than 10
inches certainly not out of the question. Of course, it will be
those 1 inch amounts over 15 minutes across more urbanized landscapes
that will be of the highest threat versus double digit rainfall
over a span of several days.

On a major side note...the city (IAH) has not yet recorded a 90F
degree day this year. If this forecast pans out and overcast with
rainfall plagues the region through the weekend, then the city
would likely not meet 90F for the remainder of the week. This
would place 2016 in the Top 5 if 90F was not met by Sunday (the
latest day was on June 15th, 1897). 31

[BlueJay]

I looked back at the history of posts to compare the temperatures in 2011-that infamous year of drought.
I found this post by Ptarmigan:

Postby Ptarmigan » Sun Jun 05, 2011 5:26 pm

Today, Houston hit a record high of 105 at Intercontinental Airport. The record high is 109 set on September 4, 2000. One wonders is it possible for Houston to hit +110 or even 120? The answer is yes, especially with all the concrete and development in Houston and surrounding area. Houston is way more likely to see 100 degree days than single digit frigid temperatures. Only four instances of that happening, twice in 1899, 1930, and 1989. Also, Houston is more likely to see 100 degree days than below 20 days in Houston. However, some summers do not see 100 degree days, last happened in 1997.

viewtopic.php?f=2&t=583
User avatar
Ptarmigan
Statistical Specialist
Statistical Specialist

Posts: 2784
Joined: Wed Feb 03, 2010 8:20 pm

We were concerned about hitting 100+ temperatures in early June 2011 and now we have not even hit 90F!
Thank you again to all who post! I really enjoy and benefit from this site.