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srainhoutx
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SPC keeps Slight Risk N of Houston in Morning Update...

Image

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0752 AM CDT FRI APR 30 2010

VALID 301300Z - 011200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX AND LWR MS
VLY NWD INTO THE MID/UPR MS VLYS...

...SYNOPSIS...
UPR LOW OVER THE WRN DAKOTAS EXPECTED TO DEEPEN SLIGHTLY AS IT MOVES
SLOWLY NE INTO SRN MB THIS PERIOD. ATTENDANT POSITIVE TILT TROUGH
OVER THE CNTRL/SRN RCKYS LIKELY WILL SHOW MINIMAL EWD MOVEMENT AS
SHORTWAVE IMPULSE NOW OVER SRN CA/NV CONTINUES SE INTO NW MEXICO.

STRENGTHENING OF THE DAKOTAS LOW APPEARS TO BE TIED...IN PART...TO
100+ KT 500 MB JET STREAK NOW OVER THE SRN HI PLNS. THIS FEATURE
SHOULD REDEVELOP NNE TO THE LWR MO VLY BY THIS EVE...AND INTO THE
UPR GRT LKS EARLY SAT. AT THE SFC...THE ABOVE CHANGES WILL BE
ACCOMPANIED BY AN EWD ACCELERATION AND INTENSIFICATION OF COLD FRONT
NOW OVER THE UPR MS VLY. THE BOUNDARY SHOULD EXTEND FROM NRN MI
THROUGH SRN IL TO CNTRL TX BY 12Z SAT.

...MID/UPR MS VLY...
VERY STRONG LOW LVL FLOW WILL PREVAIL AHEAD OF STRENGTHENING COLD
FRONT OVER THE MID/UPR MS VLY TODAY...WITH 850 MB SSW FLOW AOA 50
KTS. THIS WILL ALLOW INCREASINGLY RICH MOISTURE TO OVERSPREAD
REGION...WITH PW RANGING FROM AROUND 1.25 INCHES IN WI TO ABOVE 1.50
INCHES IN MO. SFC DEW POINTS NEAR 60F SHOULD YIELD SBCAPE OF
1000-1500 J/KG...WITH THE HIGHEST VALUES EXPECTED IN MO.

A FEW ELEVATED TSTMS MAY PERSIST THROUGH THE MORNING FROM ERN KS
INTO THE UPR MS VLY. THIS ACTIVITY SHOULD BE JOINED AND/OR REPLACED
BY NEW SFC-BASED DEVELOPMENT AS SFC HEATING DESTABILIZES REGION BY
EARLY AFTN. THE STORMS LIKELY WILL CONTINUE TO STRENGTHEN THROUGH
THE REST OF THE DAY AS UPR JET STREAK REDEVELOPS NNE ACROSS REGION.
CLOUDS AND DIFFUSE NATURE OF EXISTING FRONTAL ZONE/OUTFLOW
BOUNDARIES COMPLICATE THE PICTURE. BUT ATTM IT APPEARS THAT THE
AXIS OF STRONGEST STORM DEVELOPMENT WILL EXTEND FROM WRN/CNTRL MO
NNE INTO CNTRL/ERN IA AND WRN WI AS UPLIFT FOCUSES ALONG RESIDUAL
OUTFLOW/DIFFERENTIAL HEATING BOUNDARIES NEAR FRONT.

60-70 KT DEEP SSWLY SHEAR ORIENTED ROUGHLY PARALLEL TO THE LOW LVL
FOCUSING FEATURES SHOULD BE FAVORABLE FOR A MIX OF SEMI-DISCRETE
SUPERCELLS AND/OR BROKEN LINES WITH EMBEDDED SUPERCELLS/LEWPS.
GIVEN THE STRENGTH OF THE MEAN FLOW AND INCREASING MOISTURE...ANY
SUSTAINED STORMS WILL POSE A RISK FOR HIGH WIND...HAIL...AND A FEW
TORNADOES. FAST NNE STORM MOVEMENT SHOULD EXTEND THE SVR THREAT
INTO ERN WI AND WRN/NRN IL BY EVE. A DIMINISHING THREAT MAY PERSIST
INTO EARLY SAT OVER ERN/SRN IL.

...ARKLATEX/SRN OZARKS/LWR MS RVR VLY...
SATELLITE AND GPS DATA SHOW AN AREA OF MORE SIGNIFICANT MOISTURE
/WITH PW NEAR 1.50 INCHES/ NOW ALONG THE NWRN GULF THAT SHOULD
CONTINUE TO MOVE N INTO E TX...THE LWR MS VLY AND SRN OZARKS THROUGH
THE PERIOD. SCTD TSTMS...MOST OF WHICH MAY BE ELEVATED...MAY FORM
OVER NE TX/ERN OK AND AR LATER THIS MORNING THROUGH EARLY THIS AFTN
AS LOW CLOUDS LIMIT SFC HEATING. BUT THE MAIN FOCUS FOR SVR WX OVER
THE REGION SHOULD BE LATER THIS AFTN INTO TONIGHT AS INCREASINGLY
MOIST/CONFLUENT FLOW PERSISTS BENEATH DIFLUENT HIGH LVL
JET...SUPPORTING BANDS OF SUSTAINED STORMS.

WHILE HEIGHT CHANGES WILL BE NEGLIGIBLE...COMBINATION OF 45-50 KT
SWLY 500 MB FLOW ATOP 35-40 KT SSWLY LLJ SHOULD SUPPORT EMBEDDED
SUPERCELLS WITH VERY LARGE HAIL AND A FEW TORNADOES. THE STORMS MAY
PERSIST WELL INTO THE NIGHT INTO ERN AR AND THE LWR TN VLY AS COLD
FRONT SAGS SE INTO REGION AND PROVIDES AN ADDITIONAL SOURCE OF LOW
LVL ASCENT AMIDST INCREASING MOISTURE.

..CORFIDI/GARNER.. 04/30/2010
Carla/Alicia/Jerry(In The Eye)/Michelle/Charley/Ivan/Dennis/Katrina/Rita/Wilma/Humberto/Ike/Harvey

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kayci
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Since I am far from Weather Expert status... sometimes I have a hard time reading these things what with all the abbreviations and such. Care to put this in laymans terms?
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srainhoutx
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kayci wrote:Since I am far from Weather Expert status... sometimes I have a hard time reading these things what with all the abbreviations and such. Care to put this in laymans terms?
Sorry about your beach day kayci. Streamer showers with a chance of some heavier rain later today. ;) Tomorrow we may see a better chance of some heavier showers/storms as the front approaches. We shall see.
Carla/Alicia/Jerry(In The Eye)/Michelle/Charley/Ivan/Dennis/Katrina/Rita/Wilma/Humberto/Ike/Harvey

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srainhoutx wrote:
kayci wrote:Since I am far from Weather Expert status... sometimes I have a hard time reading these things what with all the abbreviations and such. Care to put this in laymans terms?
Sorry about your beach day kayci. Streamer showers with a chance of some heavier rain later today. ;) Tomorrow we may see a better chance of some heavier showers/storms as the front approaches. We shall see.

Thanks srain.... I shall put 'plan B' in motion then.
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wxdata
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Today's score for SE TX-

Monstrous Cap 1 Severe Weather 0

11am update:
SPC: slight risk stays in northeast Texas; moderate risk now for the mid/upper-Mississippi Valley
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wxdata
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THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
DENSE FOG ADVISORY...WHICH IS IN EFFECT UNTIL 7 AM CDT SATURDAY.
A SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING.

SOUTHEAST WINDS OF BETWEEN 15 TO 25 KNOTS WILL PERSIST THROUGH
THE AFTERNOON. THE LONG FETCH AND DURATION OF THESE ONSHORE WINDS
WILL INCREASE SEA HEIGHTS AND SWELL OVER THE COASTAL WATERS TO
AROUND 7 FEET.

THE COMBINATION OF WARM MOIST AIR OVERRIDING COOL SHELF WATERS HAS
RESULTED IN THE DEVELOPMENT OF DENSE SEA FOG OVER GALVESTON BAY
AND THE COASTAL WATERS JUST OFF THE GALVESTON COASTLINE. THIS FOG
IS EXPECTED TO PERSIST THROUGH TONIGHT WITH VISIBILITIES DROPPING
TO BELOW 1/2 NAUTICAL MILE AT TIMES.
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wxdata
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SPC concerned about northeast Texas for severe threat; SE TX stays cloudy, damp and humid..

http://www.spc.noaa.gov/products/md/md0422.html
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wxdata
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Wow, high risk now in Arkansas!
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Neat 3D relative velocity slice of the tornado near Little Rock @ 9:10pm
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Ptarmigan
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wxdata wrote:Today's score for SE TX-

Monstrous Cap 1 Severe Weather 0

11am update:
SPC: slight risk stays in northeast Texas; moderate risk now for the mid/upper-Mississippi Valley
The cockroach cap is still there. :evil: I guess the cans of RAID failed. :evil:
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Ptarmigan
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Ed Mahmoud wrote:
FXUS64 KHGX 301525
AFDHGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1025 AM CDT FRI APR 30 2010

.DISCUSSION...
50 KNOT LOW LEVEL JET IN PLACE OVER SE TX RESULTING IN A QUICK
RETURN OF LOW LEVEL MOISTURE. GPSMET DATA SHOWS PWS HAVE INCREASED
TO 1.1-1.3 INCHES. 850 MB DEWPOINTS ARE NOW IN THE 12-14C RANGE
WITH SFC DEWPOINTS IN THE LOWER 70S. THE WARM ADVECTION AND LOW
LEVEL JET RESULTING IN SPOTTY LIGHT RAIN OVER THE AREA. EXPECTING
THE LIGHT RAIN TO TAPER OFF BY EARLY TO MID AFTN. THE MAIN
FORECAST CONCERN IS THE CONVECTIVE POTENTIAL TODAY/TONIGHT. 12Z
CRP/LCH SOUNDINGS SHOW A MONSTROUS CAP IN PLACE. 700 MB ANALYSIS
SHOWS TEMPS OF +12C OVER OUR WRN ZONES WITH EVEN SHV AT +11C. COLD
FRONT REMAINS OVER WEST TX AND WILL REMAIN WELL TO OUR WEST
THROUGH TONIGHT. GIVEN THE EXTENSIVE CLOUD COVER AND LACK OF ANY
SFC BOUNDARY...THINK THE CAP WILL OVERCOME ANY POTENTIAL FOR
SEVERE WEATHER TODAY AND TONIGHT. HAVE LOWERED POPS TO MATCH
LATEST MAV/MET GUIDANCE...MOSTLY 20S EXCEPT 30S OVER THE NORTHERN
THIRD. WILL ONLY MENTION THUNDER OVER THE NORTHERN THIRD. WILL
UPDATE THE HWO TO REMOVE MENTION OF SEVERE TODAY AND TONIGHT.
DESPITE THE CLOUDS...TEMPS SHOULD STILL GET VERY WARM THIS AFTN.

35
I rather call that monstrous cap the cockroach cap.
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Severe Thunderstorm Watch
SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 120
NWS STORM PREDICTION CENTER NORMAN OK
100 AM CDT SAT MAY 1 2010

SEVERE THUNDERSTORM WATCH 120 IS IN EFFECT UNTIL 900 AM CDT
FOR THE FOLLOWING LOCATIONS

TXC019-021-027-029-031-035-053-055-091-099-137-145-171-187-193-
209-217-259-265-267-271-281-287-293-299-307-309-319-325-327-331-
333-385-395-411-435-453-463-465-491-011400-
/O.NEW.KWNS.SV.A.0120.100501T0600Z-100501T1400Z/

TX
. TEXAS COUNTIES INCLUDED ARE

BANDERA BASTROP BELL
BEXAR BLANCO BOSQUE
BURNET CALDWELL COMAL
CORYELL EDWARDS FALLS
GILLESPIE GUADALUPE HAMILTON
HAYS HILL KENDALL
KERR KIMBLE KINNEY
LAMPASAS LEE LIMESTONE
LLANO MASON MCCULLOCH
MCLENNAN MEDINA MENARD
MILAM MILLS REAL
ROBERTSON SAN SABA SUTTON
TRAVIS UVALDE VAL VERDE
WILLIAMSON
sleetstorm
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Ed Mahmoud wrote:Friday afternoon is potentially interesting, 'specially if 850 mb winds are from the South and not the SSW or SW

Image

Some nice turning with height...

Image

Just a guess, based on 700 mb RH fields, we may be near the edge of the cap of forged titanium coated steel, hammered and folded over a charcoal fire over and over again by a Japanese master. But we may be at the edge, not under, the cap. 850 r. humidities (trust me, you can't quite see them, 850 mb RH around 90%) suggest no cap there, anyway.

Image
A cap made of titanium forged coated steel, hammered and folded over a charcoal fire over and over again by a Japanese master, Ed Mahmoud? That is a hilarious metaphor the way that you put it. :lol: Laughed silently to myself
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Where is the jedi master with his crystal light saber to kill the cockroach cap? :lol:
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Ptarmigan
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sleetstorm wrote:Where is the jedi master with his crystal light saber to kill the cockroach cap? :lol:
And a very good light sabre to ensue that the cockroach cap never comes back ever again.
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