May: Slight Risk Severe Storms Thursday To End The Month

[srainhoutx]

Finally getting a MD in the Moderate Risk area...

MESOSCALE DISCUSSION 0986
NWS STORM PREDICTION CENTER NORMAN OK
0547 PM CDT WED MAY 30 2012

AREAS AFFECTED...WRN OK

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 302247Z - 310015Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...A FEW SEVERE STORMS MAY OCCUR OVER WRN OK...WITH MAINLY AN
HAIL AND WIND THREAT. A NARROW N/S WATCH MAY BE NEEDED SOON.

DISCUSSION...STORMS HAVE DEVELOPED OVER WRN/SWRN OK...E OF THE TX
ACTIVITY WHERE CAPPING HAS BEEN LOCALLY BREACHED. THESE STORMS ARE
RELATIVELY WEAK AT THIS TIME...BUT STEEP LAPSE RATE PROFILES AND
NWLY DEEP LAYER SHEAR AROUND 40 KT WILL FAVOR SOME FURTHER
ORGANIZATION.

BOUNDARY LAYER TEMPERATURE/DEWPOINT SPREADS ARE CURRENTLY AROUND 25
F...DUE TO MARGINAL LOW LEVEL MOISTURE WITH DEWPOINTS ONLY IN THE
UPPER 50S TO LOWER 60S F. HOWEVER...CONDITIONS MAY CHANGE THIS
EVENING WITH A PERSISTENT SLY LOW LEVEL JET AND SOME HIGHER THETA-E
OVER NWRN TX.

..JEWELL/CORFIDI.. 05/30/2012

[srainhoutx]

TORNADO WARNING
TXC155-275-310000-
/O.NEW.KOUN.TO.W.0050.120530T2313Z-120531T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
613 PM CDT WED MAY 30 2012

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
FOARD COUNTY IN NORTH TEXAS...
NORTHWESTERN KNOX COUNTY IN NORTH TEXAS...

* UNTIL 700 PM CDT

* AT 610 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
A TORNADO IS VERY LIKELY NEAR HACKBERRY...MOVING SOUTHEAST AT 15
MPH.

* THIS TORNADIC THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS
OF SOUTHWESTERN FOARD AND NORTHWESTERN KNOX COUNTIES.

[Andrew]

A lot of storms firing in North Texas. Outflow boundaries are flowing everywhere and especially in central Texas/ East Texas. More storms could fire with the collision of these boundaries but with the loss of daylight heating storms should begin quieting down later tonight.

[Andrew]

Getting some very strong winds and rotation with that storm Southwest of Crowell

[srainhoutx]

Nice shot before the end of the day...thanks for the gr imagery, Andrew... Hopefully tomorrow will being us some much needed rainfall...

[Katdaddy]

Very explosive supercells with Tornado Warnings in effect across NW TX. It will be very interesting to see how the storms progress this evening.

[Ptarmigan]

We could see some storms on Thursday. Should be interesting.

[unome]

check out the waves going thru SE TX http://www.ssd.noaa.gov/goes/east/wfo/hgx.html

shows up better in a loop

[srainhoutx]

The front is creeping S and E and will likely slow a tad further as the day wears on. We'll have to wait until later in the day when the sea breeze activity begins to fire and left over boundaries collide and hopefully activity fires off along that slow moving frontal boundary. That said morning storms did get close to College Station...




SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
709 AM CDT THU MAY 31 2012

TXZ162-175-311245-
LEON TX-ROBERTSON TX-
709 AM CDT THU MAY 31 2012

...SIGNIFICANT WEATHER ADVISORY FOR...
LEON COUNTY
ROBERTSON COUNTY

AT 709 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
CLUSTER OF STRONG THUNDERSTORMS EXTENDING FROM THORNTON TO
FAIRFIELD...MOVING SOUTHEAST AT 25 MPH.

WIND GUSTS TO 50 MPH CAN BE EXPECTED FROM THIS STORM.

[srainhoutx]

Morning e-mail from Jeff:

A risk of severe thunderstorms across the entire region today and tonight.



Already an active morning just to our north with a line of severe thunderstorms from Waco to just north of Centerville moving SE at 30mph. This line has actually been increasing in intensity over the past few hours and may hold together long enough to make it into at least the northern ½ of SE TX. Damaging winds to 60mph will be the main threat with this line.



Will be interesting to see how this complex may affect late day expected development, given the current radar trends a well defined outflow boundary will likely overspread much of the region later this morning from this complex and it is at least possible that with modest early morning heating that this system could move to the coast. Feel even if this is the case, clouds will quickly clear and strong heating will rapidly recover the air mass back to an unstable state by mid to late afternoon. Add in a southward moving frontal boundary during peak heating and expect additional strong to severe development from the Austin to College Station to Livingston area this afternoon which will then move south across the area into the evening hours. A forecasted very unstable air mass will support severe thunderstorms with the main threats being large damaging hail and strong damaging winds to 60mph. Feel most if not all areas are at risk today/tonight as capping in the mid levels looks to be overcome, although areas around Matagorda Bay may see the least activity. At least many areas should see one/maybe two rounds of storms with wetting rainfall to help ease our current dry spell.



Front should push on offshore early Friday with pleasant early June weather of lows in the 60’s and highs near 90 through the weekend. Models continue to show a more classic summer pattern of seabreeze storms each afternoon next week as the high pressure aloft remains fairly modest over the region.

[srainhoutx]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0744 AM CDT THU MAY 31 2012

VALID 311300Z - 011200Z

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING FROM
PORTIONS OF THE OH VALLEY SWWD INTO THE LOWER MS VALLEY AND WWD INTO
CNTRL/SRN TX...

...SYNOPSIS...

THE SEWD PROGRESSION OF A MID LEVEL JET STREAK FROM THE CNTRL HIGH
PLAINS INTO OZARK PLATEAU/MID-SOUTH WILL CONTRIBUTE TO THE
AMPLIFICATION OF LARGE-SCALE TROUGH OVER THE MS VALLEY WITH
SUBSEQUENT UPPER LOW FORMATION FORECAST OVER THE UPPER MIDWEST BY
01/12Z. WITHIN THIS BROADER-SCALE PATTERN...A NUMBER OF
PERTURBATIONS --SOME OF CONVECTIVE ORIGIN-- WILL SHIFT EWD FROM THE
OZARKS AND SRN PLAINS THROUGH THE MID/LOWER MS VALLEY.

AT THE SURFACE...LOW PRESSURE OVER CNTRL MO WILL DEVELOP ENEWD
ACROSS THE OH VALLEY WHILE TRAILING COLD FRONT...INITIALLY FROM THE
OZARKS TO SRN HIGH PLAINS...ADVANCES SEWD TOWARD THE NWRN GULF
COAST. A WARM FRONT WILL PRECEDE THE MIGRATORY SURFACE
LOW...GRADUALLY LIFTING NWD THROUGH THE OH VALLEY.

...OH/TN/LOWER MS VALLEYS...

RADAR MOSAIC SHOWS A COUPLE OF MCVS THIS MORNING WITHIN PRE-FRONTAL
WARM SECTOR...ONE OVER S-CNTRL MO...AND THE OTHER NEAR THE ARKLATEX.
CONVECTION ASSOCIATED WITH BOTH OF THESE FEATURES HAS WEAKENED
DIURNALLY...THOUGH RESIDUAL COLD POOLS AND DEEPER-LAYER FORCING
ATTENDANT TO THESE VORTICITY MAXIMA WILL LIKELY PROMOTE AN INCREASE
IN STORM COVERAGE AND VIGOR BY LATE MORNING/EARLY AFTERNOON OVER THE
LOWER OH/LOWER MS VALLEYS.

12Z JAN SOUNDING SHOWED THE PRESENCE OF A VERY MOIST LOW-LEVEL AIR
MASS WHICH WILL ALLOW MLCAPE VALUES TO INCREASE TO 2000-2500 J/KG BY
AFTERNOON ACROSS THE LOWER MS VALLEY. INSTABILITY WILL DECREASE
WITH NWD EXTENT INTO THE OH VALLEY /I.E. AFTERNOON MLCAPE OF
1000-1500 J PER KG/ OWING TO A COMPARATIVELY DRIER BOUNDARY LAYER
AND THE EWD SPREAD OF HIGH CLOUDS WHICH WILL TEMPER DAYTIME HEATING.
LATEST CONVECTION-ALLOWING MODELS SUGGEST THE POTENTIAL
ORGANIZATION OF STORMS INTO MULTIPLE LINEAR CONVECTIVE SYSTEMS WITH
THE PRIMARY HAZARDS BEING SOME HAIL AND DAMAGING WINDS INTO MID-LATE
EVENING. THE THREAT FOR A TORNADO OR TWO WILL BE HIGHEST ALONG
SURFACE LOW TRACK WHERE LOCALLY BACKED NEAR-SURFACE FLOW WILL
ENHANCE LOW-LEVEL SHEAR.

...TX...

MCS CURRENTLY NE OF CLL APPEARS TO BE WELL-RESOLVED BY A NUMBER OF
CONVECTION-ALLOWING MODELS WHICH SUGGEST THAT THE SYSTEM SHOULD
CONTINUE TO WEAKEN AS IT PROGRESSES SEWD TOWARD THE UPPER TX
COAST/SWRN LA. LOW-LEVEL UPLIFT ALONG LEADING EDGE OF RESIDUAL GUST
FRONT MAY ALLOW FOR RENEWED DEVELOPMENT BY LATE MORNING/EARLY
AFTERNOON NEAR THE COAST WITHIN A MOIST AND MODERATELY UNSTABLE AIR
MASS WITH MLCAPE OF 1500-2500 J/KG. VERTICAL SHEAR WILL BE SOMEWHAT
MARGINAL FOR STORM ORGANIZATION/LONGEVITY...THOUGH THE PRESENCE OF
STEEP MIDLEVEL LAPSE RATES AND WATER-LOADING EFFECTS MAY ENHANCE
DAMAGING WIND AND HAIL POTENTIAL.

FARTHER W...12Z DRT/CRP/BRO SOUNDINGS ALL SHOWED THE PRESENCE OF A
VERY MOIST BOUNDARY LAYER /I.E. LOWEST 100-MB MEAN-MIXING RATIOS OF
AROUND 16 G PER KG/ AND STEEP MIDLEVEL LAPSE RATES...RESULTING IN AN
ALREADY MODERATE-STRONGLY UNSTABLE ENVIRONMENT. HOWEVER...A STRONG
CAP OBSERVED AT THE BASE OF THE EML CASTS CONSIDERABLE UNCERTAINTY
ON EVENTUAL STORM COVERAGE LATER TODAY. CURRENT THINKING IS THAT AN
OUTFLOW BOUNDARY NOW SETTLING SWD THROUGH NRN PARTS OF THE EDWARDS
PLATEAU...THE ARRIVAL OF THE SYNOPTIC COLD FRONT LATER
TODAY...AND/OR ENHANCED LOW-LEVEL UPSLOPE INTO THE HIGH TERRAIN OF
SWRN TX/NRN MEXICO MAY PROVIDE THE FOCUS FOR ISOLATED-WIDELY
SCATTERED TSTM DEVELOPMENT BY LATE AFTERNOON/EARLY EVENING. ANY
STORMS THAT INITIATE WILL LIKELY BECOME SUPERCELLS OWING TO MLCAPE
OF 2000-3000 J/KG...VERTICALLY VEERING WIND PROFILES...AND THE
CO-LOCATION OF THE SUBTROPICAL JET WHICH WILL ENHANCE DEEP-LAYER
SHEAR/UPDRAFT VENTING. VERY LARGE HAIL WILL BE THE MAIN THREAT WITH
THESE STORMS.

...SRN CO/NRN NM...

STEEP LAPSE RATES AND POST-FRONTAL DEWPOINTS IN THE 40S WILL YIELD A
MARGINALLY UNSTABLE ENVIRONMENT BY LATE AFTERNOON/EARLY EVENING
WITHIN THE LEE OF THE HIGHER TERRAIN. LOW-LEVEL UPSLOPE FLOW MAY BE
AUGMENTED BY THE SEWD PROGRESSION OF A WEAK MIDLEVEL
IMPULSE...GIVING RISE TO ISOLATED STORM DEVELOPMENT LATER TODAY.
GIVEN THE PRESENCE OF THE STEEP LAPSE RATES AND 30-35 KT OF DEEP
NWLY SHEAR...SETUP MAY SUPPORT A MARGINAL WIND/HAIL THREAT THROUGH
THIS EVENING.

..MEAD/ROGERS.. 05/31/2012

[srainhoutx]

05312012 13Z TX VIS latest.jpg

[Kludge]

0.25" so far here. Gusts to 38

[srainhoutx]

0.25" so far here. Gusts to 38

Awesome! Those of us in areas N of I-10 have been lacking of late. It is interesting to see the gravity waves again this morning across Central Texas and storm activity in the Dallas area much like Kansas saw yesterday. We are clearly un capped this morning across the Houston Metro area, but it may take a bit more time for storms to develop and I suspect the we'll need to watch t our West later in the day for strong cells to fire with the heating of the day. Fingers crossed.

[srainhoutx]

The 12Z WRF/NMM is suggesting things may pop across the area later in the day. One thing to note is that most of the guidance has had a difficult time with meso features and boundary issues as we saw yesterday. Just something to keep in mind.

[srainhoutx]

Storms are beginning to back build W further N along the front in N Central Texas...

[srainhoutx]

Looking good along the front...

[srainhoutx]

MESOSCALE DISCUSSION 0994
NWS STORM PREDICTION CENTER NORMAN OK
0947 AM CDT THU MAY 31 2012

AREAS AFFECTED...SE TX...SW LA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 311447Z - 311545Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...AN ISOLATED SEVERE THREAT WILL LIKELY CONTINUE ACROSS SE
TX AND SW LA THROUGH EARLY AFTERNOON. STRONG GUSTY WINDS AND HAIL
WILL BE PRIMARY THREATS WITH THE ACTIVITY. THE AREA WILL CONTINUE TO
BE MONITORED FOR THE POSSIBILITY FOR WW ISSUANCE.

DISCUSSION...A LINE OF THUNDERSTORMS ACROSS EAST TX IS LOCATED JUST
AHEAD OF A SHORTWAVE TROUGH EVIDENT ON WATER VAPOR IMAGERY. THE
SHORTWAVE TROUGH WILL SUPPORT THE LINE FOR SEVERAL HOURS WITH THE
LINE MOVING SEWD INTO MODERATE INSTABILITY CURRENTLY IN PLACE ACROSS
SE TX AND SW LA. MESOANALYSIS ESTIMATES THAT MLCAPE IS IN THE 1500
TO 2500 J/KG RANGE WHICH WILL HELP SUSTAIN THE CONVECTION. IN
ADDITION...AN AXIS OF STRONG MID-LEVEL FLOW IS LOCATED ACROSS CNTRL
AND SOUTH TX WITH 0-6 KM SHEAR VALUES ACROSS SE TX IN THE 25 TO 45
KT RANGE. THIS ALONG WITH MID-LEVEL LAPSE RATES APPROACHING 8.0 C/KM
SHOULD SUPPORT A HAIL THREAT WITH THE STRONGER CELL ELEMENTS
EMBEDDED IN THE LINE. AS LOW-LEVEL LAPSE RATES STEEPEN AHEAD OF THE
LINE OVER THE NEXT FEW HOURS...THE WIND DAMAGE THREAT MAY INCREASE
ESPECIALLY IF THE LINE CAN DEVELOP A PERSISTENT BOWING STRUCTURE.

..BROYLES/WEISS.. 05/31/2012


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

[Andrew]

It is very cool looking at visible and radar to see all the outflow boundaries and the gravity waves. They are very defined and shows the energy associated with these storms. Looks like a stormy afternoon with the front coming through.

http://www.ssd.noaa.gov/goes/east/wfo/h ... h-vis.html

[srainhoutx]

Our neighbors to the E have a Severe Thunderstorm Watch hoisted. Front continues to creep S and E and storms continue to fire along the boundary. Heating continues in our NW and W areas, so we'll need to watch those areas for possible future development as the afternoon wears on...HGX Update...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1021 AM CDT THU MAY 31 2012

.UPDATE...
RAGGED LINE OF SHOWERS AND STORMS HEADING MORE EAST THAN SOUTH
ACROSS THE EAST-CENTRAL CWA. THIS LINE IS EXPECTED TO CONTINUE ITS
MORE EASTWARD TREK OUT OF THE CWA. THE EASTERN FLANK OF THE UPSTREAM
LINE OF CONVECTION (ALONG A STEPHENVILLE TO WACO TO CENTERVILLE
LINE) WILL LIKELY CLIP/AFFECT OUR MORE NORTHWESTERN AND CENTRAL FA
OVER THE NEXT 3-6 HOURS. THE HIGHEST POP IS TARGETED OVER THESE
AREAS...OR OVER COUNTIES THAT HAVEN`T BEEN WORKED OVER FROM THIS
MORNING`S ACTIVITY. IN SHORT...THE DOWNSTREAM ENVIRONMENT IS STILL
VERY CONDUCIVE FOR THE FORMATION OF MID TO LATE SCATTERED SHOWERS
AND THUNDERSTORMS...POSSIBLY REACHING SEVERE LIMITS. THE UPPER
LEVELS WILL BECOME LESS DIFFULENT THROUGH THE DAY...BUT THE VICINITY
OF THE LF QUAD OF A SOUTHWESTERN TEXAS JET STREAK AND A MID-LEVEL
TROUGH MAY BE ALL OF THE UPPER SUPPORT NEEDED FOR CONTINUED LATTER
DAY CONVECTION. THE MAIN COLD FRONT (CURRENTLY JUST SOUTH OF THE RED
RIVER VALLEY) IS FORECAST TO SAG SLOWLY DOWN NEAR THE COAST BY
MIDNIGHT AND BECOME NEAR-STATIONARY THROUGH FRIDAY MORNING. HIGHER
POPS WILL BE FOCUSED ABOUT THIS FEATURE AND WHERE HIGHER MOISTURE IS
FORECAST TO POOL...OR ALONG AND SOUTH OF THE I-10 CORRIDOR (SE
FORECAST AREA) DURING THE OVERNIGHT HOURS.