JUNE 2015 -Scattered Showers/Storms To End The Month

[GBinGrimes]

Agree with you completely Tireman. This season has been very, very interesting indeed. Thinking back to this past winter, we also were within a degree or two or three of having some very interesting "wintry mischief" on a few occasions along the Gulf Coast. It's been interesting for quite awhile.

One thing that is almost certain with Texas weather, it's either exceeding dry or exceedingly wet and the same goes for the temp fluctuations in the seasons. I don't think we have true mild\seasonal\normal weather that stays to the "averages". Nothing is average EXCEPT the average!

... and as always, when a cold front makes it into the Gulf and stalls there during the hurricane season, one must be aware that unexpected things can happen ...

That said, no models I've seen suggest tropical development associated with this feature ...

This is one of the most interesting seasons I have lived through in awhile. Copious amounts of rain for the area, a tropical storm that moved in a way not expected by anyone or the models, a cold front in late June...what will the the rest of 2015 bring us...hummm

[brooksgarner]

Here's an interesting feature.

A semi-permanent low pressure system over South America (due to heat) and the Azores/Bermuda high is creating a particularly strong gale this season, blowing WNW at 30-45mph -- which is also semi-permanent with this setup, and the forecast for this high wind continues thru at least the next week and a half+.

El Nino may be enhancing heating over the tropical regions of South America, further strengthening their heat low relative to the Azores high. This makes pressure gradient more dramatic and winds stronger.

If anything tropical tried to form in the southern Caribbean in this setup, it'd be ripped apart faster than a smash cake at a 1yo's birthday party.

Folks on cruise ships are loving the swell (not.)

[Paul Robison]

Ahm'a gonna pree-tend dey din' say dat:

THE MID AND UPPER LEVELS WILL ALSO PLAY A ROLE FOR THE DAILY SEA
BREEZE TO BE MORE OF A PLAYER IN PRODUCING THURSDAY AND FRIDAY
SCATTERED AFTERNOON CONVECTION AS REGIONAL HEIGHTS BEGIN TO
SLOWLY DECLINE. PROGGED THU AND FRI THERMO PROFILES ARE MOIST AND
UNSTABLE ENOUGH TO SUPPORT LOCALLY STRONG TO ISOLATED SEVERE
STORMS...INVERTED V`S WITH STEEP LOWER LEVEL LAPSE RATES EQUATING
TO GREATER THAN 2K CAPES/-7 OR -8 L.I.`S WITHIN GT 1.8 INCH PWATS
AND CONVECTIVE TEMPS OF AROUND 90F.

[fingers in ears] LA LA LA--I AIN'T LISTENIN'

[srainhoutx]

The overnight computer guidance schemes continue to support a stalling frontal boundary across Eastern portions of Texas into Central Louisiana on Saturday Into Sunday. An West to East line of strong to possibly severe storms could develop Saturday afternoon and push toward the Coast Saturday night into early Sunday morning. Various mesoscale features and outflow boundaries may set the stage for additional storms developing on Sunday, but there is some uncertainty at this range exactly where or who may see the greatest threat for strong to possibly severe storms. The GFS and Euro are suggesting a very strong upper low developing near the Ohio Valley digging a rather deep trough across the Eastern half of the United States. Out West, record high temperatures are expected across the Pacific Northwest and the monsoon season kicks off in Eastern Arizona into New Mexico. Embedded disturbances in the upper Northerly flow aloft may send additional storms chances across the Southern Plains into the Eastern half of Texas early next week as additional deep tropical moisture streams N off the Gulf of Mexico. There continues to be indications that this unsettled pattern continues for most of next week as a weakness between the Western Ridge and the Eastern trough remains in place over Texas. Additional showers and storms appear likely as we end the month of June.

[srainhoutx]

No real changes this afternoon regarding the upcoming weekend sensible weather outlook. We are seeing a bit more coverage of seabreeze thunderstorms this afternoon and that trend should increase again tomorrow.

[Paul Robison]

Rain chances for Sunday:

Houston: 40%
Lake Charles, LA: 50%
New Orleans, LA: 58%

IF this verifies, I'd say Houston's coming in last with rain, or at least heavy rain. We're safer here than in New Orleans.

[nuby3]

speaking of rain, getting a pretty nice soaking up on the north side right now. been storming for more than an hour

[Paul Robison]

An West to East line of strong to possibly severe storms could develop Saturday afternoon and push toward the Coast Saturday night into early Sunday morning.

All strong and severe storms?

[nuby3]

speaking of rain, getting a pretty nice soaking up on the north side right now. been storming for more than an hour

nope. pretty big inference there. he wasn't implying that at all

[srainhoutx]

The pattern change that has been anticipated is underway across North America. A +PNA regime has developed and the upper ridge across the Western United States is strengthening while a deepening trough is underway across the Eastern half of the US. An upper low in the Western Gulf of Mexico is slowly meandering N and we are already seeing returns on the radar scope over the Coastal waters moving N. A robust shortwave over the Ohio Valley will push a cool front into Eastern Texas tomorrow before pulling up stationary N of I-10 providing a focus for afternoon and evening thunderstorms to develop. PW's have increased to the 2.3+ range with a surge of tropical moisture moving toward the Texas and Louisiana Coasts. The Storm Prediction Center has outlined a Marginal Risk for severe storms across portions of East/SE Texas into Louisiana. Expect storms will continue into Sunday and possibly into Monday before the stalled boundary retreats N and washes out. With a +PNA regime except a NW flow aloft to continue into next week with daily 'Ring of Fire' thunderstorm development with the monsoon to our West and upper air disturbances dropping S out of Canada into the Plains. Moisture levels look to remain high with an onshore flow off the Gulf with an uncapped atmosphere overhead. Showers and storms should continue into next week possibly decreasing slightly by later next week.

[Katdaddy]

The SPC has most of SE TX in a marginal risk area for tomorrow.

[srainhoutx]

Convective temperatures have been met and storms are developing quickly across SE Texas. The cold front is advancing S through the Panhandle and crossing the Red River at this hour. The upper low/trough in the Western Gulf continues to pump in deep tropical moisture from the NW Caribbean Sea setting the stage for a wet and stormy weekend across portions of our Region.

[galvbay]

Had a heavy shower come through Smith Point today around 2:00pm.... .33" of rain in about 10 minutes. galvbay

[Paul Robison]

The SPC has most of SE TX in a marginal risk area for tomorrow.

Better than being in the Slight Risk area. From SPC:

DEEP
SHEAR WILL BE RELATIVELY MORE MODEST TO THE SW OF THE SLIGHT-RISK
AREA...MITIGATING CONVECTIVE ORGANIZATION AND PRECLUDING A MORE
SUBSTANTIAL SVR RISK.

Slight Risk includes: Baltimore, MD...Charlotte, NC...Washington, DC...Virginia Beach, VA...Atlanta, GA...

What do you think, Katdaddy?

[srainhoutx]

The latest short range High Resolution Rapid Refresh guidance suggests showers and some stronger storms will be slow movers capable of dropping heavy rainfall where the more organized convection develops this afternoon and tonight. It appears the weak diffuse cool front will not reach Metro Houston, but may near the Austin area before stalling out and then lifting back N as a warm front. The Storm Prediction Center continues with a Marginal Risk for severe storms today across portions of S Central and SE Texas extending into Louisiana.

[srainhoutx]

From Nesdis:

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 06/27/15 1251Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-683-1404
LATEST DATA USED: GOES-13 1230Z KUSSELSON
.
LOCATION...CENTRAL TEXAS...
.
ATTN WFOS...HGX...FWD...EWX...SJT...
ATTN RFCS...WGRFC...
.
NESDIS IS CONTINUING TO ACCEPT APPEALS ON THE RETIREMENT OF THE SPENES
PRODUCT. APPEALS CAN BE SUBMITTED BY EMAILING JOHN.SIMKO@NOAA.GOV
.
EVENT...MERGED CELLS THAT HAVE FORMED A CONVECTIVE BAND DROPPING SOUTH
CENTERED ON THE NORTHERN EWX CWA AND ALSO AFFECTING FRINGE S FWD, SE
SJT AND NW HGX AREA...
.
SATELLITE ANALYSIS AND TRENDS...UNSEASONABLE TROUGH INTO THE SOUTHERN
PLAINS AND CONNECTED TO EVEN MORE UNSEASONABLE VORT LOBE ALONG THE
MI-IN-OH BORDER AREA. SO CLOSE TO UPPER LEVEL HIGH ALL AS PER LATEST
GOES WATER VAPOR LOOP THAT IT WAS HIGHLY DIFFLUENTER CENTRAL TEXAS.
AND ON TOP OF THAT MULTIPLE AREAS OF CONVECTION THAT RECENTLY HAVE MERGED
THEIR VARIOUS SEGMENTS OVER THE NORTHERN EWX CWA FOR LOCALLY HVY RAINS
THAT CAN PERSIST THROUGH AT LEAST MID MORNING MASON TO LLANO TO BURNETT
TO WILLIAMSON COUNTY. MERGED CELLS THE BEST PAST HR LLANO TO BURNET AND
WITH MAX PWATS OF 1.7"-2.0"..CERTAINLY COULD BE RATES THAT PERSIST IN THAT
RANGE FOR AN HR OR SO AS MOVEMENT OF MODERATE TO HVY RAIN WILL BE SLOW.

SHORT TERM OUTLOOK VALID 1245-1545Z...MEDIUM CONFIDENCE FACTOR
IN SHORT TERM OUTLOOK...DESPITE GENERAL WARMING CLOUDS...NARROW FOCUS
OF THE MERGED CELLS KEEPING INDIVIDUAL CELLS/OVERSHOOTING CLOUD TOPS
GOING CENTERED OVER THE NORTHERN EWX CWA FOR THE NEXT FEW HRS AS HIGH
MOISTURE CENTERED JUST NORTH ADVECTS INTO AREA AND INSTABILITY AS PER
GOES SOUNDER AND DIFFLUENCE CONTINUE. SEE GRAPHIC SHORTLY FOR AREA MOST
CONCERNED THE NEXT FEW HRS...

[Katdaddy]

Srain has the local area weather covered well as always. Just a reminder that even though a quiet hurricane season is forecast thanks to El Nino, it only takes one.

Today marks the 58th year anniversary of Hurricane Audrey which made landfall along the SW LA coast as a CAT 4. Keep in mind this was also an El Nino year with only 8 named storms but it only takes one.

1957 was an El Nino year. Ask any survivors of Audrey if it was a quiet hurricane season. This is the time to be prepared.

[Katdaddy]

This morning's Hou-Gal AFD update indicates a heavy rain event is possible later today and overnight.

.UPDATE...
TALE OF TWO ZONES THIS MORNING...OVERCAST OVER THE NORTHERN ZONES
IN RESPONSE TO THE (BECOMING) STATIONARY BOUNDARY LAYING SOMEWHERE
OVER THE PINEY WOODS/JUST NORTH OF THE CWA WITH THE CONTRAST OF
MAINLY SUNNY SKIES OVER THE SOUTHERN FORECAST AREA. THIS SCENARIO
WILL TIGHTEN THE REGIONAL THERMAL GRADIENT THAT MAY ALLOW THIS
SLOWING BOUNDARY TO SAG INTO THE CENTRAL CWA...AS WELL AS GENERATING
A SEA BREEZE BOUNDARY...AS SOUTHERN COUNTY AFTERNOON TEMPERATURES
WARM INTO THE LOWER 90S. THE MERGER OF THESE TWO FEATURES HAVE
THE POTENTIAL TO SET-UP A HEAVY RAIN EVENT LATTER TODAY AND INTO
THE EARLY SUNDAY MORNING HOURS...NEAR STATIONARY CLUSTERS OF
RAIN/STORMS FOCUSING HIGH RAINFALL RATES OVER THE SAME AREA(S).

[srainhoutx]

Thunderstorms have initiated along a leftover boundary extending from the Edwards Plateau on E to just S of Temple. The latest HRRR suggests a W to E line of thunderstorms may organize into a slow moving QLCS (quasi linear convective system) and slowly sag S into the Western areas of SE Texas including DT Houston this evening.

[srainhoutx]

Afternoon briefing from Jeff:

A slow moving frontal boundary will interact with the northward moving seabreeze front late this afternoon and evening to produce scattered to numerous showers and thunderstorms….some of the rainfall will be heavy.

Ill defined frontal boundary located over central and north TX with a pre-frontal trough/outflow boundary over the northern sections of SE TX. Daily seabreeze boundary is taking shape near the coastline and starting its northward movement. Cloud cover this morning has hampered a rapid warm up, but upper 80 to lower 90 degree trigger temperatures are starting to be reached and showers/thunderstorms are starting to develop. High resolution models like the idea of thunderstorms increasing through the afternoon hours and forming in WSW to ENE bands across the region this would be ahead of the outflow boundary to the north and the seabreeze to the south. These boundaries look to collide somewhere between I-10 and HWY 105 this evening. Some of the models keep the activity going most of the night with very slow storm motions and some cell training.

Moisture levels are certainly respectable (on the order of 2.0in + PW air mass overhead) and overnight slow storm motions south of Waco put down a quick 3-4 inches of rainfall. Not much confidence in where the heaviest rains may fall this evening into the overnight hours with the band looking fairly narrow on the high resolution models.

Rainfall totals of 1-2 inches will be possible with higher isolated totals of 3-5 inches under slow moving heavy thunderstorms. Grounds remain moist from TS Bill rainfall last week and scattered rainfall this week. Hourly rainfall rates under the stronger storms could be on the order of 2-3 inches.