May 2016: Shower/Storm Chances To End May

[unome]

possibly of interest to weather watchers: http://www.ssd.noaa.gov/PS/SATS/SPBULL/ ... 804.01.txt

• Topic: *GOES-13 (GOES-East) Standard CONUS RSO
  
  *Date/Time**Issued: *May 24, 2016 0800Z
  
  *Product(s) or Data Impacted:*GOES-13 (GOES-East) Imager Data and Products**
  
  *Date/Time of Initial Impact:*May 24, 2016 1814Z******
  
  *Date/Time of Expected End:* May 25, 2016 0014Z****
  
  *Length of Event:*6 hours**
  
  *Requester: *Storm Prediction Center
  
  *Details/Specifics of Change:***Severe weather monitoring over the Central Plains **
  
  There will be an increased number of GOES-13 (GOES-East) Rapid Sectors, with decreased coverage for the Southern Hemisphere and smaller Northern Hemisphere scans.*
  *
  
  *Contact Information for Further Information:* ESPC Operations at ESPCOperations@noaa.gov and 301-817-3880 or Satellite Analysis Branch Shift Supervisor at _SABSupervisor@noaa.gov_ and 301-683-1400.
  **
  
  *Web Site(s) for applicable information:*
  
  *See http://www.ssd.noaa.gov/PS/SATS/GOES/EAST/sched.html and http://www.ssd.noaa.gov/PS/SATS/GOES/WEST/sched.html for scanning schedules.
  

GOES East RSO Schedule: http://www.ospo.noaa.gov/Operations/GOES/east/rso.html

[srainhoutx]

Deep tropical moisture associated with a tropical wave near the SW Caribbean Sea continues to slowly advance WNW. A series of disturbances embedded around a Western trough and upper low near California will be our main sensible weather driver later this week. We will need to monitor Thursday night into Friday for any developing thunderstorm complexes that may organize across the Hill Country and move ESE as the upper trough edges a bit closer. The dryline is expected to inch closer to the I-35 Corridor. Interestingly we are seeing an MJO pulse move across the Pacific toward the Eastern Pacific and Western Caribbean Sea. The Global models have been struggling as of late with some features on the Global Scale, so it will be interesting to see exactly how things unfold. Those heading to the Hill Country Lakes and Rivers need to closely monitor the weather forecasts in the days ahead. All the Highland Lakes and Rivers are running above normal and any additional heavy rainfall could increase the Flash Flood threat again as it did last Thursday shutting down the Comal and Guadalupe Rivers.

[BiggieSmalls]

In simple terms, why is it 10/10 humidity right now, even in North Texas? Its felt about as miserable as it can get over the last few days...Bring on the high pressure system to park over us for weeks!

[srainhoutx]

Tuesday morning briefing from Jeff:

Strong storm system will approach TX late this week.

Omega blocking pattern with troughs on the east and west coasts and high pressure in the center of the nation will gradually break down as the western US trough begins to move eastward.

Latest forecast guidance indicates this western US trough moving into TX starting Thursday and really impacting the area on Friday. Ingredients appear to be coming together to produce strong to severe thunderstorms and flooding rainfall on Friday afternoon and evening. Moderate to high instability, a splitting jet structure and tropical moisture all point to an excessive rainfall threat as well as large hail and damaging winds. It is likely the meso scale will dominate the activity by Friday with potential for NC TX convective cluster to send an outflow boundary into the region on Friday. Main question is how far south this boundary progresses.

Until late week, the air mass will feature moderate to at times strong low level flow off the Gulf of Mexico with humid and warm conditions in place. Highs may push 90 on Wednesday over a large portion of the region away from the coast. Thunderstorm chances begin to increase on Thursday with the approach of the trough to our west.

Tropics:
There appears to be a low potential for a tropical or sub-tropical system to form late this week over the Bahamas south of a ridge of high pressure which will build over the NE US. Several of the forecast models are trying to close off a weak area of low pressure within the ESE to SE steering under the belly of this high. Interest along the SE US coast should monitor the progress of this system.

[unome]

heat index 99... even with a mostly cloudy day... ugh...

http://w1.weather.gov/data/obhistory/KDWH.html

Area Forecast Discussion
National Weather Service Houston/Galveston TX
345 PM CDT TUE MAY 24 2016

.DISCUSSION...
Surface dew points were very warm today and heat index values
were closing in on 100 degrees. Warm and humid conditions will
prevail again Wednesday into Thursday. A few showers had developed
this afternoon beneath a weak capping inversion and near a weak
850-700 mb convergence zone. With the loss of heating and the
weakening of the convergence, feel precipitation will come to an
end around sunset. Skies should remain mostly cloudy overnight and
min temps will remain very warm. Upper level ridging will remain
over SE TX on Wednesday but PW values will approach 1.85 to 2.00
inches during the afternoon. The jet structure shows a bit of a
split over SE TX and upper level winds look divergent between
15-21z. Fcst soundings show quite a bit of dry air between 850-600
mb and a weak cap near 700 mb. Have added slight rain chances for
Wednesday due to the high moisture content and favorable jet
dynamics despite the mid level drying/cap.

Forecast soundings show a saturated column developing below 850 mb
on Wednesday night. Could get a few streamer showers beneath the
cap on Wednesday night so will maintain slight rain chances.
Thursday is looking more interesting as PW values surge to near
2.00 inches and a weak short wave moves across SE TX. Upper level
winds will once again split over SE TX and the combination of
these three ingredients should compensate for some slightly drier
air in the 850-700 layer and a weak capping inversion which should
easily erode by 18z. Will stay with chance PoPs for now but likely
PoPs may ultimately be required on Thursday, particularly over the
NW half of the region.

Rain chances should remain high on Friday as a strong and neutral
to negatively tilted upper trough moves east across the Southern
Plains. SE TX will lie in a well defined jet couplet with PW
values near 2.00 inches. CAPE values will be close to 3500 J/Kg
and LI values between -9 and -11 over the northern zones so some
of the storms could become strong to severe over the NW half.
Will maintain likely PoPs on Friday for areas away from the coast
and taper slightly lower toward the coast and over the gulf.

Some uncertainty for the weekend and early next week as global
models diverge in their respective upper air patterns. The GFS
builds a ridge over SE TX Sunday through Tuesday while the
Canadian and ECMWF maintain a weak upper trough and SW flow aloft.
Will maintain slight rain chances Sunday thru Tuesday and will
await models to build a consensus. 43

&&

.MARINE...
A moderate on-shore flow will continue for the next several days.
SCEC flags are up for all coastal and offshore waters through 7 AM
Wednesday morning. Winds may fall below SCEC criteria Wednesday and
Thursday as the axis of the surface ridge shifts to the east,
however the gradient tightens again later in the week, possibly
pushing winds to advisory levels on Friday. Winds and seas should
gradually subside over the Memorial Day Weekend as the gradient
loosens once again.

The current weather pattern sets up a long fetch to the Western
Carribean. Tide levels will gradually increase for the next several
days with a Coastal Flood Advisory possible for Friday as the
predicted tide levels near 3.5 feet may cause flooding of lower
lying areas on the Bolivar Peninsula and along Toddville Road in
Seabrook. 44

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 74 88 73 81 72 / 10 20 20 50 30
Houston (IAH) 75 88 75 85 74 / 20 20 20 40 30
Galveston (GLS) 78 83 77 82 77 / 10 20 20 30 20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through Wednesday 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...Waters from Freeport to
the Matagorda Ship Channel from 20 to 60 NM...Waters from
High Island to Freeport from 20 to 60 NM.

[Katdaddy]

The 2016 Atlantic Basin Hurricane Season is saying hello this evening.

SPECIAL TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
335 PM EDT TUE MAY 24 2016
For the North Atlantic...Caribbean Sea and the Gulf of Mexico:
An area of showers and thunderstorms over the western Atlantic Ocean
near and northeast of the Bahamas is associated with the
interaction of an upper-level trough and a weakening cold front.
While development is not expected for the next couple of days,
environmental conditions could become more conducive for some
tropical or subtropical development by Friday. This area of
disturbed weather is expected to move slowly west-northwestward or
northwestward and gradually approach the southeastern United
States over the next few days. The next Special Tropical Weather
Outlook will be issued by 4 PM EDT Wednesday.
* Formation chance through 48 hours...low...near 0 percent
* Formation chance through 5 days...low...30 percent

[srainhoutx]

Active end of the workweek shaping up that could remain unsettled throughout the Memorial Day Holiday Weekend. The WPC as outlined a Slight Risk for Excessive Rainfall for Thursday and Friday across our Region.

[srainhoutx]

Wednesday morning briefing from Jeff:

Strong upper level storm system to bring heavy rainfall and severe weather to TX Thursday and Friday

Large upper level storm system over the SW US will begin to lift into the plains later today with weak disturbances eject out of the main upper level flow and across TX. Air mass over TX is moist and unstable and just awaiting a trigger to set off showers and thunderstorms. Hazy conditions of the current air mass suggest it has originated in the southern Gulf of Mexico where smoke from Mexican agriculture fires has spread into the Bay of Campeche.

A strong short wave will eject out of Mexico later today and likely fire strong to severe thunderstorms along the dry line over SW TX. Some of the models develop this activity into an eastward moving MCS across SC TX tonight while other dissipate the storms as they move eastward. Interestingly some models fire numerous thunderstorms early Thursday afternoon over the W/NW sections of SE TX in an area between College Station and Columbus. These storms look to be slow moving and could possibly force a surface boundary that remains nearly stationary into the evening hours. Will need to watch this potential very closely on Thursday afternoon for rapid onset flash flood threat over our NW/W counties where slow moving excessive rainfall could develop.

Much of what happens Thursday afternoon will determine how things play out Thursday night and Friday. Certainly feel if development over our NW counties is significant Thursday afternoon, this will play a big role on Friday with boundaries in place.

Overall confidence is low moving forward with where severe weather and heavy rainfall risks are highest. Currently favoring NW of a line from Columbus to Lake Livingston to rain chances decreasing southward where sub-tropical ridging is attempting to build northward from the Gulf and Mexico.

Could certainly see some very heavy rainfall with storms with PWS at 2.0 inches. High hourly rainfall rates will be possible. Will go with 2-3 inches NW of a line from Columbus to Lake Livingston with 1-2 inches SE of this line, but isolated totals could be significantly higher. This also could be adjusted SE with any kind of outflow boundary. Could be a fairly strong rainfall gradient across SE TX with NW areas seeing a lot of rain and coastal/SE areas not seeing much at all.

Severe threat is generally on the low side, but would not rule out a large hail or damaging wind report with all the instability in the air mass.

[DoctorMu]

lol With the GoM moisture conveyer belt on full force, the fires in Mexico strike again as cloud seeing!


I should have put in that JennAir for hamburgers years ago.



At least the sprinklers stay off! So no complaints in CLL.

[brooksgarner]

Tough call because if this rain sets up farther north -- in the literal sense that global models (GFS) have consistently placed the heaviest bands near Dallas to Waco -- Houston doesn't see much. Of course, if a meso-high from a cold pool develops on the backside of an MCS, we could easily see all that north Texas stuff work toward us.

Found an interesting article on man-made contributing factors to the flooding: http://www.texasmonthly.com/the-daily-p ... ostmortem/

[DoctorMu]

GFS places the moderate deluge from NW Harris Co to Killeen. Another 3.2 inches of rain here in CLL

Per Brooks, watch the outflow boundaries.

[unome]

MESOSCALE DISCUSSION 0733
NWS STORM PREDICTION CENTER NORMAN OK
0807 PM CDT WED MAY 25 2016

AREAS AFFECTED...PORTIONS SW TX.

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 260107Z - 260230Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...POTENTIAL EXISTS FOR WW GIVEN INCREASING CONVECTIVE TRENDS
OVER WRN PARTS OF DISCUSSION AREA...IN FAVORABLY MOIST/UNSTABLE AIR
MASS. HOWEVER CINH WILL REMAIN STG...SO SVR THREAT REMAINS
CONDITIONAL.

DISCUSSION...SFC MESOANALYSIS SHOWS WAVY DRYLINE EXTENDING FROM SWRN
OK TO IRION COUNTY...WWD TO BETWEEN FST-PEQ...THEN ARCHING SWD/SSEWD
ACROSS BREWSTER COUNTY INTO BIG BEND REGION. DRYLINE MAY RETREAT
SLIGHTLY NWWD THROUGH EVENING.

THOUGH MIXED SIGNALS ARE EVIDENT REGARDING SHORT-TERM CONVECTIVE
THREATS...NARROW WINDOW APPEARS TO EXIST FOR MORE THAN ISOLATED
SFC-BASED CONVECTION INITIATION ALONG OR JUST E OF DRYLINE...AND/OR
TRANSITION OF ABUNDANT/SHALLOW/MIDLEVEL CONVECTION CROSSING FROM DRY
AIR TO ITS W TO BECOME SFC-BASED. 00Z DRT RAOB SHOWED STG CAP AT
BASE OF STEEP LAPSE RATES THAT COMBINED WITH SFC DEW POINTS NEAR 75
DEG F TO SUPPORT 4000 J/KG MLCAPE. HOWEVER...CINH SHOULD BE WEAKER
ON HIGHER TERRAIN NW OF THERE OVER LOWER PECOS RIVER REGION...WHERE
BOUNDARY-LAYER HEATING ALSO HAS BEEN STRONGER ALONG NWRN PERIPHERY
OF PERSISTENT HIGH-CLOUD DECK. ANY TSTMS THAT CAN BECOME
SUSTAINED/MATURE BEFORE ENTERING REGIME OF STRONGER CAPPING MAY
ORGANIZE SUFFICIENTLY WITH EITHER INTERNALLY GENERATED/MESOCYCLONIC
PERTURBATION OR FORCED ASCENT ASSOCIATED WITH AGGREGATED COLD POOLS.
EITHER SUPERCELLULAR OR CLUSTERED/MULTICELLULAR MODES...
RESPECTIVELY...MAY ENABLE SUCH STORM MAINTENANCE. HOWEVER
ORGANIZATION NEEDS TO BE MAINTAINED LONG ENOUGH IN FACE OF SUCH
CINH.

DEEP SHEAR IS FAVORABLE FOR SUPERCELLS WITH EFFECTIVE-SHEAR
MAGNITUDES 40-50 KT...AND CURRENT WEAKNESS IN LOW-LEVEL WINDS THAT
CURRENTLY IS KEEPING SRH SMALL ON HODOGRAPHS MAY INTENSIFY SOME IN
NEXT 2-3 HOURS WITH ONSET OF LLJ. HOWEVER...DIABATIC COOLING ALSO
WILL INCREASE MLCINH GRADUALLY. CONVECTIVE TRENDS ARE BEING
MONITORED FOR POSSIBLE WW.

..EDWARDS/CORFIDI.. 05/26/2016


ATTN...WFO...EWX...SJT...MAF...

meanwhile, more tornadoes

https://twitter.com/islivingston/with_replies?lang=en
https://twitter.com/EricBlake12/with_replies?lang=en

[Ptarmigan]

Tough call because if this rain sets up farther north -- in the literal sense that global models (GFS) have consistently placed the heaviest bands near Dallas to Waco -- Houston doesn't see much. Of course, if a meso-high from a cold pool develops on the backside of an MCS, we could easily see all that north Texas stuff work toward us.

Found an interesting article on man-made contributing factors to the flooding: http://www.texasmonthly.com/the-daily-p ... ostmortem/

Forecast models do get rain amount right, but not the location right.

[srainhoutx]

The overnight guidance continues to indicate that the heaviest rainfall will occur mainly N and W of Metro Houston with lesser amounts near the Coast throughout the Memorial Day Holiday Weekend. Strong to possibly severe thunderstorm development is expected across Central Texas and the Hill Country Lakes and Rivers. Will need to monitor any mesoscale features that cannot be determined beyond 6 or so hours closer to Metro Houston particularly Thursday afternoon through Saturday morning as a neutral to negative tilted trough advances E into the Plains along with any left over cold pool boundaries and an extremely tropical airmass with PW's around 2+ inches in place. If the capping inversion erodes, heavy rainfall rates are possible where training storms develop.

[srainhoutx]

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
448 PM CDT WED MAY 25 2016

...PUBLIC INFORMATION STATEMENT...

THE N.O.A.A. WEATHER RADIO FOR HOUSTON IN TOMBALL KGG68 162.40
MHZ HAS A DAMAGED ANTENNA AND HAS A RESTRICTED COVERAGE AREA OF
ONLY ABOUT 3 TO 5 MILES. TECHNICIANS ARE WORKING AT THE SITE BUT
NO ESTIMATE OF WHEN REPAIRS WILL BE COMPLETED ARE AVAILABLE YET.

OTHER RADIO TRANSMITTERS COVER PORTIONS OF THE SAME AREA.
THESE TRANSMITTERS COVER MUCH OF THE SAME AREA BUT MAY BE ON
DIFFERENT FREQUENCIES.

THE BYRAN WXK30 AT 162.55 COVERS THE NORTHWESTERN AREAS. THE FORT
BEND WZ2572 162.475 MHZ COVERS THE SOUTH HARRIS AND AREAS TO THE
SOUTHWEST. GALVESTON KHB40 162.50 COVERS CENTRAL AND SOUTHEAST
HARRIS COUNTY AND AREAS TO THE SOUTHEAST. BEAUMONT WXK28 162.475
COVERS LIBERTY AND CHAMBERS COUNTY AND THE ONALASKA KXI55 162.50
MHZ COVERS WALKER, PORTIONS OF MONTGOMERY AND NORTHERN LIBERTY
COUNTIES.

[srainhoutx]

MESOSCALE PRECIPITATION DISCUSSION 0238...CORRECTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
807 AM EDT THU MAY 26 2016

CORRECTED FOR GRAPHIC

AREAS AFFECTED...CENTRAL & SOUTHEAST TX

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 261203Z - 261803Z

SUMMARY...AS CIN ERODES THIS MORNING, CONVECTION IS EXPECTED TO
INCREASE IN COVERAGE. WITH SUBSTANTIAL INSTABILITY AND MOISTURE
IN PLACE, HOURLY RAIN RATES TO 2.5" AND LOCAL AMOUNTS OF 3-5"
COULD LEAD TO FLASH FLOODING.

DISCUSSION...WHAT WAS ONCE FORWARD PROPAGATING CONVECTION ACROSS
CENTRAL TX HAS BEEN SLOWING DOWN AS OF LATE AS ITS RELATED OUTFLOW
BOUNDARY HAS SLOWED DOWN, PER SURFACE OBSERVATIONS. RADAR IMAGERY
REVEALS TWO HEAVY RAIN CORES NEAR AND AHEAD OF THE OUTFLOW
BOUNDARY ACROSS PORTIONS OF THE TX HILL COUNTRY/CENTRAL TX. AHEAD
OF THIS FEATURE, A DEW POINT GRADIENT HAS SET UP SHOP FROM ROUGHLY
PORT ARTHUR TO AUSTIN TX. PRECIPITABLE WATER VALUES ARE 1.7-2" IN
THIS AREA PER GPS VALUES, WITH SOUTH-SOUTHWEST 30 KTS OF INFLOW
PER VAD WIND PROFILES ADVECTING IN 2000-3500 MLCAPES INTO THE
REGION. SPC MESOANALYSES INDICATE THAT BOTH MUCIN AND MLCIN ARE
ALREADY ERODING ACROSS CENTRAL AND SOUTHEAST TX.

THE MESOSCALE/CAM GUIDANCE, LED BY THE TRIO OF HRRR GUIDANCE AS
WELL AS THE 06Z NAM (4 KM) CONEST AND 00Z SPCWRF, APPEAR TO
INDICATE THE HEAVY RAINFALL POTENTIAL BEST IN THIS REGION, SHOWING
LOCAL AMOUNTS IN THE 3-5" RANGE, WHICH COULD FALL QUICKLY. THE
AVAILABLE MOISTURE SUPPLY SUPPORTS HOURLY RAIN RATES UP TO 2.5",
WHICH COULD BE EXCEEDED IN CELL MERGERS. THE 06Z GFS-BASED
GALVEZ-DAVISON INSTABILITY INDEX SHOWS INCREASING VALUES WITHIN
TIME HERE, RISING FROM 35 PAST 45 BY 18Z, IMPLYING NUMEROUS
SHOWERS AND THUNDERSTORMS ARE POSSIBLE BY 18Z. PULSE ACTIVITY
SHOULD MOVE EAST-NORTHEAST TO NORTHEAST AT ~ 30 KTS, THOUGH
ORGANIZED CONVECTIVE CLUSTERS WOULD TRACK MORE EAST TO
EAST-SOUTHEAST AT 25-35 KTS WHICH COULD LEAD TO THE MERGERS.
ACTIVITY WOULD BE INITIALLY ELEVATED OVER THE DEW POINT BOUNDARY
BEFORE BECOMING MORE SURFACE-BASED LATER THIS MORNING INTO THIS
AFTERNOON. FLASH FLOODING IS A CONCERN, PARTICULARLY WITHIN URBAN
AREAS WHERE DRAINAGE OF HEAVY RAINFALL IS A CONCERN, LIKE HOUSTON
TX.

ROTH

ATTN...WFO...EWX...FWD...HGX...SJT...

[srainhoutx]

Thursday morning briefing from Jeff:

Heavy rainfall and severe weather possible over the next 48 hours.

A strong storm system currently over S AZ will swing E then ENE across the southern plains over the next 48 hours providing lift across a moisture and unstable air mass over TX. Low level southeasterly flow over the last 3 days has brought an extremely moist western Caribbean air mass into the region with surface dewpoints of 72-77 over the region and PWS of 1.8-2.0 inches. Lead short wave is starting to eject across TX currently with lift increasing along the I-35 corridor where local radars show the formation of showers and thunderstorms. Capping is still evident over SE TX and will require mid 80 degree temperatures to break…which should be attainable once the low cloud deck burns off.

Not sure really any of the short range high resolution models have a good handle on the convective development today. TX TECH WRF is way overdone so think it may be too aggressive, but the HRRR does not look all that better. Both models show significantly more development this morning than what is taking place…possibly due to the capping in place. Will favor the western and NW counties for the greatest storm chances starting later this morning and peaking this afternoon/evening. Overall meso pattern is one of favorable forced low level boundaries within a highly moist and unstable air mass supporting strong to severe thunderstorms and very heavy rainfall.

One concern is the potential for any sustained outflow boundary to become perpendicular to the decent 20kts of low level inflow this afternoon and evening which would greatly raise the flash flood threat and the severe threat. Think the best chances of this happening would be from Columbus to Huntsville, but these types of setups almost always like to attempt to drift SE into the low level Gulf feed.

Friday looks like an even better setup for severe thunderstorms and heavy rainfall, but will greatly depend on just much development and where this development occurs today. Main trough axis approaches which will help to erode the capping over the area and the upper level winds become strongly divergent supporting sustained lift. Do think it is going to take much to get storms going. Latest meso models…if they are to be believed…show both an early morning round of storms followed by a second round of slower moving storms dropping SE from NC TX during the late afternoon and evening hours. Low confidence that this is going to work out this way with the potential for any morning storm complex to stabilize the air mass.

Memorial Day Weekend:

Unlike 2015 which brought devastating flooding to TX, 2016 should be more tranquil with weak ridging attempting to develop aloft. Could still see some activity on Saturday before moisture levels drop. SW US mean upper trough position reloads by late Sunday into Monday and the next slow moving strong upper level storm system begins to head for TX early to mid next week in a pattern that has been locked in place now for the last 6 weeks.

ATL: 91L

Surface low pressure has developed over the SW ATL north of the Caribbean Sea on the tail end of an old frontal trough. 25-30kts of SW wind shear have resulted in little to no thunderstorm formation around this surface low, but conditions are expected to become increasingly favorable for development as the system drifts toward the WNW and NW this weekend allowing deep convection to build closer or over the low level center.

The National Hurricane Center currently gives the system a 70% of tropical cyclone formation over the next 5 days. Interest along the SE US coast from NC to FL should closely monitor the progress over this system. A USAF hurricane hunter mission is currently scheduled for early Friday to determine if a tropical depression or tropical storm is forming.

NOTE: effective with the 2016 hurricane season, storm surge inundation graphics will be provided by NHC with each advisory package when a tropical system is within 48 of landfall. These maps will show the reasonable worst case storm surge above ground level based on the expected forecast track of the tropical system. These maps should be available roughly 1 hour after the official advisory package is released from NHC.

[/i]

[DoctorMu]

Just got slammed in CLL by a cell that could turn severe as it heads NW. Storms cell near Waco developing an outflow boundary, and the boundary is heading SE.

[DoctorMu]

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1004 AM CDT THU MAY 26 2016

.DISCUSSION...
Activity moving in from the SW starting to get its act together
this morning as we are beginning to see some lightning with the
storms. Current grids look good - with highest pops over north-
ern counties and slightly lower closer to the coast. PWs around
2" already over the region along with increasing instability to
help things unsettled over SE TX these next couple of days. 41

&&

.PREV DISCUSSION...

Still looking for increasing rain chances across Southeast Texas
over the next two days as a series of disturbances move across the
state and help to ignite shower and thunderstorm development. Best
support/ lift/instability for possible strong/severe storms and
locally heavy rainfall still looks to be setting up across parts
of our western and northwestern counties. However, based on a
number of different scenarios being shown by the models, cannot
rule out some of this risk (especially the locally heavy rainfall)
spreading further to the east and south across the rest of our
area. The primary severe weather threats will be locally heavy
rainfall (and possible localized flooding) along with
strong/damaging winds, frequent lightning and large hail. Rainfall
totals for this Thursday-Friday event are expected to range from 1
to 2 inches in and around the coastal counties to 3 to 4 inches
across our northwestern and western counties. Locally higher
amounts will be possible area wide. Looks like less rain over the
Memorial holiday weekend with lower rain chances and warmer
temperatures. Look for mainly daytime 20% to 30% rain chances
during the first half of next week as weak upper level ridging
attempts to build into the state from the south. The next upper
level trough moving slowly eastward across the state during the
second half of the week has some potential to getting us back into
a wet pattern as we start the new month. 42

[DoctorMu]

The old Waco cell and new Navasota cells are merging - getting slammed again. Big Meso possibly congealing.

Huntsville area could be under the gun for heavy rain in a couple of hours.

No flash flood warnings yet.