JUNE 2016: Showers/Storms Possible

[Katdaddy]

Just some steady rains in League City with .84" for the day.

[srainhoutx]

MESOSCALE PRECIPITATION DISCUSSION 0308
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1106 AM EDT SAT JUN 04 2016

AREAS AFFECTED...UPPER TX COAST...SOUTHWEST LA

CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY

VALID 041500Z - 042000Z

SUMMARY...VERY INTENSE RAINFALL RATES WILL CONTINUE NEAR THE UPPER
TX COAST AND GRADUALLY SPREADING INTO SOUTHWEST LA OVER THE NEXT
FEW HOURS. FLASH FLOODING WILL BE LIKELY GIVEN THE WET ANTECEDENT
CONDITIONS.

DISCUSSION...THE LATEST IR SATELLITE IMAGERY DOES SHOW SOME
EXPANSION OF COLDER CONVECTIVE TOPS OVER THE FAR NORTHWEST GULF OF
MEXICO IN ASSOCIATION WITH THE NORTHERN FLANK OF A LARGE MCS THAT
EXTENDS WELL SOUTHWEST OFF THE SOUTHEAST TX COAST. THERE IS A
RATHER WELL-DEFINED MID LEVEL CIRCULATION OVER THE SOUTHEAST TX
COASTAL PLAIN AND THIS HAS BEEN TRANSLATING DOWN TO THE SURFACE AS
WELL OVER BASED ON METAR DATA OVER THE LAST FEW HOURS.

THE CONCENTRATION OF LOW AND MID LEVEL LOW PRESSURE NEAR THE TX
COAST IS EXPECTED TO CONTINUE TO HELP TRANSPORT DEEPER MOISTURE
AND INSTABILITY IN OFF THE NORTHWEST GULF OF MEXICO AND TOWARD
AREAS OF THE FAR UPPER TX COAST AND INLAND ACROSS FAR EASTERN TX
AND SOUTHWEST LA. RAP ANALYSES ALREADY SHOW A POOL OF NEARLY 3000
J/KG OF MUCAPE ALONG THE SOUTHWEST LA COAST.

THE BLENDED-TPW PRODUCT AND GPS DATA SHOWS PWATS CLOSE TO 2 INCHES
OVER THIS REGION...AND WITH A RATHER DEEP POOL OF MOISTURE AND
COLD CONVECTIVE TOPS...THE ENHANCED RAINFALL EFFICIENCY SHOULD
HELP PUSH RAINFALL RATES EASILY IN THE 2 TO 3 INCH/HR RANGE.

THE OVERALL BETTER PERFORMING HRRR OUTPUT CONTINUES TO WANT TO
FOCUS THE HEAVIEST RAINFALL OUT OVER THE GULF OF MEXICO THROUGH
EARLY TO MID AFTERNOON...BUT THE SLOW NORTH-NORTHEAST ADVANCE OF
THE CONVECTION NEAR THE UPPER TX COAST AND LA BORDER SHOULD AFFORD
SOME OVERSPREADING OF VERY HEAVY RAINS INTO FAR EASTERN TX AND
SOUTHWEST LA OVER THE NEXT FEW HOURS. THE POTENTIAL EXISTS FOR
SOME RAINFALL TOTALS TO REACH UP TO 5 INCHES WITH ISOLATED HEAVIER
AMOUNTS THROUGH MID-AFTERNOON GIVEN THE SLOW CELL-MOTION AND SUCH
HIGH RAINFALL RATES. FLASH FLOODING IS LIKELY WITH A RISK OF
LOCALLY SIGNIFICANT RUNOFF PROBLEMS GIVEN THE WET SOIL CONDITIONS.

ORRISON

ATTN...WFO...HGX...LCH...

[ticka1]

looks like its moving east - not seeing this stalling here in houston area

[StormOne]

looks like its moving east - not seeing this stalling here in houston area

That's what I was thinking. Could still see heavy rain in the afternoon but I'm not thinking it will be a flash flood threat.

[mckinne63]

Seeing some peeks from that yellow blob in the sky! Ie: Sunshine.

[srainhoutx]

Additional showers and thunderstorms are possible this afternoon and evening as the surface low and an area of convergence cross the Region as the upper trough sinks S into S Texas. Still could see isolated to scattered storms into Monday, but hopefully some drier air will arrive and rain chance diminish.

Next weekend we will need to monitor an Easterly wave progressing towards the NW Gulf as well as lower pressures associated with a monsoonal trough roughly from the Gulf of Tehuantepec in the Eastern Pacific extending into the Bay of Campeche/NW Caribbean Sea. A weak surface wave may attempt to develop and head generally NW toward the Mexico and Texas Gulf Coasts.

Edit to add: Many locations have achieved or exceeded our annual normal rainfall for SE Texas as of today.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
1100 AM PDT SAT JUN 4 2016

For the eastern North Pacific...east of 140 degrees west longitude:

1. An area of low pressure located about 1100 miles south-southwest
of the southern tip of the Baja California peninsula is moving
westward at 10 to 15 mph. Although the associated showers and
thunderstorms have increased, the circulation of the system is
elongated and the center is not well defined. Some development of
this system is still possible and a tropical depression could form
during the next couple of days while the low continues westward.
After that time, environmental conditions are expected to become
less conducive for development.
* Formation chance through 48 hours...medium...50 percent
* Formation chance through 5 days...medium...50 percent

2. An area of disturbed weather has formed several hundred miles south-
southeast of Acapulco, Mexico. Some gradual development of this
system is possible during the next few days while it moves slowly
northeastward. Regardless of development, locally heavy rains are
likely later this weekend and early next week over portions of
southern Mexico and Guatemala.
* Formation chance through 48 hours...low...10 percent
* Formation chance through 5 days...low...20 percent

Forecaster Cangialosi

[ticka1]

is the wave why we have rain in the forecast next weekend?

[Heat Miser]

I guess when David Paul forecast just last night all this would be out of here by 12 noon he was talking the bulk? Because the radar trends show many, many showers behind the bulk.

[mckinne63]

I saw in today's Chronicle that Lake Travis is now at 689", normal level is 681.

It is very cloudy here again. Looking at the radar, the showers look to have pushed off the coast and heading East. Are we on tap for more? We certainly don't need any more! Dh and I pulled up a palm rootball this afternoon, the soil is so saturated, water was just spilling into the hole. And the Brazos needs to drain and let those poor folks begin clean up.

[Rip76]

Not looking at satellite (only radar), it appears the center of the main ULL is right over Houston.

Am I seeing this right?
If so... I would imagine with any daytime heating at all, we should see some storms pop up.

[Katdaddy]

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
124 PM CDT SAT JUN 4 2016

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
SOUTHWESTERN LIBERTY COUNTY IN SOUTHEASTERN TEXAS...
NORTHWESTERN CHAMBERS COUNTY IN SOUTHEASTERN TEXAS...
EAST CENTRAL HARRIS COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 430 PM CDT

* AT 123 PM CDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
HEAVY RAIN ACROSS THE WARNED AREA. OVER 4 INCHES OF RAIN HAVE
FALLEN IN THE WARNED AREA OVER THE PAST HOUR. FLASH FLOODING IS
EXPECTED TO BEGIN SHORTLY. THESE THUNDERSTORMS ARE NEARLY
STATIONARY OVER I-10 NEAR BAYTOWN.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
BAYTOWN...BEACH CITY AND WESTERN MONT BELVIEU.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES AS
WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNED AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY.

[srainhoutx]

Not looking at satellite (only radar), it appears the center of the main ULL is right over Houston.

Am I seeing this right?
If so... I would imagine with any daytime heating at all, we should see some storms pop up.

Looks like a 700mb low over Harris County with a couple of weak surface lows along a trough axis along the Coast. One of those weak lows is near Matagorda Bay and another near Sabine Pass.

[Rip76]

Thank you.

Where is the main ULL situated now?

[srainhoutx]

Saturday briefing from Jeff:

Luckily morning complex of storms remained offshore where 5-7 inches of rainfall was recorded

Mid and upper level low pressure system has sheared into an elongated trough axis which extends from NE TX to SW TX with SE TX laying nearly directly under the axis this afternoon. Numerous thunderstorms have begun to develop within this highly moist and increasingly unstable air mass. Resulting storm motions have been 10mph or less and excessive rainfall rates are being realized over E Harris County with an incredible 4.84 inches of rainfall in 1 hr along the Harris/Chambers County line.

With additional heating expect to see an continued increase in thunderstorms with very heavy rainfall across the region. A quick 2-3 inches of rainfall is certainly possible under the stronger cells resulting in rapid flash flooding.

Tropical air mass and shear axis remains over the area in Sunday and will keep rain chances going tonight and into Sunday before pulling back to a more summer pattern of daily seabreeze storms starting Monday.

River Updates:

Brazos River:
Major flooding continues across Fort Bend and Brazoria Counties with the river only falling very slowly at Richmond and rising to near crest at Rosharon. Massive low land flooding of the river flood plain is in progress across much of southern Fort Bend County into Brazoria County.

West Fork of the San Jacinto River:

River is slowly falling, but remains above flood stage

[/i]

[Heat Miser]

If what developed near Mont Belvieu and has sat there for a long time is any indication of what could happen today with these storms it could be very, very bad for a select few. Any storm that develops on or near you appears to have a good chance of sitting there quite a while. Just doesn't appear like the low is getting out of here in a big hurry.

[srainhoutx]

HGX is stating 6.4 inches of rainfall has occurred in the past 3 hours near Mont Belvieu. Radar is under estimating rainfall totals by at least 70%.

[jasons2k]

Well it looks like the center of the circulation is right over in that vicinity, slowly drifting ese.

[srainhoutx]

FLOOD ADVISORY
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
222 PM CDT SAT JUN 4 2016

LIBERTY TX-CHAMBERS TX-HARRIS TX-
222 PM CDT SAT JUN 4 2016

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLOOD ADVISORY FOR...
SOUTH CENTRAL LIBERTY COUNTY IN SOUTHEASTERN TEXAS...
NORTHWESTERN CHAMBERS COUNTY IN SOUTHEASTERN TEXAS...
NORTHEASTERN HARRIS COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 415 PM CDT

* AT 221 PM CDT...DOPPLER RADAR INDICATED HEAVY RAIN DUE TO NEARLY
STATIONARY THUNDERSTORMS ALONG INTERSTATE 10. THIS WILL CAUSE
MINOR FLOODING IN THE ADVISORY AREA. UP TO TWO INCHES OF RAIN HAVE
ALREADY FALLEN.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
BEACH CITY...MONT BELVIEU...OLD RIVER-WINFREE AND COVE.

[ticka1]

HGX is stating 6.4 inches of rainfall has occurred in the past 3 hours near Mont Belvieu. Radar is under estimating rainfall totals by at least 70%.

Its bad.

[srainhoutx]

HGX is stating 6.4 inches of rainfall has occurred in the past 3 hours near Mont Belvieu. Radar is under estimating rainfall totals by at least 70%.

Its bad.

I see via HCFCD gauge at Cedar Bayou almost 9.5 inches has fallen in the past 24 hours.