STORM2K

Extremeweatherguy wrote:Could definitely be interesting.

Hopefully we get some good storms out of this in OKC! It has been well over 2 weeks since we have seen any rain at all.

...CNTRL AND SRN PLAINS...

AXIS OF MODIFIED CP AIR WILL ADVECT NWD THROUGH THE SRN AND CNTRL
HIGH PLAINS ALONG A STRONG SLY LOW LEVEL JET. MEANWHILE...STEEPER
MID LEVEL LAPSE RATES WILL LIKELY SPREAD EWD OVER THE MOIST AXIS AND
CONTRIBUTE TO POTENTIAL FOR DESTABILIZATION DURING THE DAY. MODELS
SUGGEST CLOUDS AND ELEVATED CONVECTION COULD BEGIN FAIRLY EARLY OVER
WRN TX AS LIFT WITHIN UPPER JET EXIT REGION OVERSPREADS THE WARM
SECTOR. THE EXTENT AND EVOLUTION OF CLOUD COVER REMAINS THE PRIMARY
UNCERTAINTY AND COULD LIMIT DEGREE OF INSTABILITY AS WELL AS OVERALL
THREAT. HOWEVER...LOW LEVEL MOISTENING AS WELL AS HEIGHT FALLS
ATTENDING UPPER TROUGH WILL RESULT IN POTENTIAL FOR AT LEAST MODEST
DESTABILIZATION. STORMS MAY BECOME SURFACE BASED AND INTENSIFY ALONG
AND JUST EAST OF LEE TROUGH DURING THE AFTERNOON. INCREASING BULK
SHEAR ASSOCIATED WITH APPROACHING UPPER JET WILL SUPPORT ORGANIZED
STORM STRUCTURES INCLUDING SUPERCELLS AND BOWING LINE SEGMENTS.
OTHER STORMS MAY DEVELOP AS THE COLD FRONT OVERTAKES THE MOIST AXIS
OVERNIGHT WITH STORMS EVENTUALLY EVOLVING INTO AN MCS BEFORE
WEAKENING AS THEY ADVANCE EWD THROUGH PARTS OF OK OVERNIGHT.

..DIAL.. 10/03/2008

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0344 AM CDT FRI OCT 03 2008

VALID 061200Z - 111200Z

...DISCUSSION...

MODELS IN AGREEMENT THAT UPPER TROUGH WILL CONTINUE INTO THE CNTRL
AND SRN PLAINS MONDAY. INDICATIONS ARE THAT LEAD IMPULSE WILL LIFT
NEWD THROUGH THE CNTRL PLAINS AND MID MS VALLEY WHILE A SECONDARY
IMPULSE DROPS SEWD INTO BASE OF UPPER TROUGH THROUGH WRN AND CNTRL
TX. VERTICAL SHEAR PROFILES WILL REMAIN SUFFICIENT FOR ORGANIZED
STORMS ALONG SRN AND ERN PERIPHERY OF UPPER TROUGH. DEWPOINTS IN THE
60S WILL LIKELY ADVECT THROUGH WARM SECTOR. SOME THREAT FOR SEVERE
STORMS WILL EXIST FROM PARTS OF N CNTRL TX THROUGH CNTRL AND ERN OK
INTO THE LOWER MS VALLEY. WITH CONVECTION EXPECTED TO BE ONGOING
AHEAD OF COLD FRONT...UNCERTAINTY STILL EXISTS REGARDING WHERE THE
BOUNDARY LAYER WILL DESTABILIZE SUFFICIENTLY TO SUPPORT A MORE
SUBSTANTIAL SEVERE THREAT. HOWEVER...A RISK AREA MAY NEED TO BE
ADDED IN LATER OUTLOOKS.
BEYOND DAY 4...MODELS SUGGEST UPPER TROUGH WILL GRADUALLY WEAKEN
OVER TX AND THE LOWER MS VALLEY BEFORE BECOMING CUTOFF FROM THE NRN
STREAM. WHILE A THREAT FOR SEVERE STORMS MAY PERSIST THROUGH DAY 6
FROM PARTS OF ERN TX INTO THE LOWER MS VALLEY...CONFIDENCE IS NOT
HIGH ENOUGH AT THIS TIME TO INTRODUCE A HIGHER END OUTLOOK AREA.

..DIAL.. 10/03/2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
304 PM CDT FRI OCT 3 2008

.DISCUSSION...
SHORT WAVE ENERGY WILL MOVE EAST OF THE REGION THIS EVENING AS
A WEAK RIDGE BUILDS IN FROM THE WEST. EXPECT LINGERING SHOWERS IN
THE EAST TO DISSIPATE BY SUNSET WITH ONLY A FEW MID AND HIGH
CLOUDS TONIGHT.

HUMIDITY WILL INCREASE SATURDAY THROUGH SUNDAY AS A SURFACE TROUGH
DEEPENS LEE OF THE ROCKIES. MID LEVEL INSTABILITY WILL ALSO BE ON
THE INCREASE AS A POWERFUL UPPER LEVEL LOW PRESSURE SYSTEM ROTATES
ACROSS THE ROCKY MOUNTAIN WEST. ENERGY FROM THIS SYSTEM...COUPLED
WITH INCREASING MOISTURE WILL BRING A CHANCE OF SHOWERS AND
THUNDERSTORMS BEGINNING IN THE NORTHWEST ZONES SUNDAY NIGHT AND
SPREADING TO ALL OF NORTH TEXAS ON MONDAY. THE BEST CHANCE OF RAIN
AND THUNDERSTORMS WILL MOST LIKELY BEGIN MONDAY NIGHT AND CONTINUE
THROUGH TUESDAY WHEN A DRY LINE AND COLD FRONT MOVE ACROSS NORTH
TEXAS. VERTICAL WIND SHEAR AND INSTABILITY SHOULD BE ADEQUATE TO SUPPORT SOME SEVERE STORMS. RAIN AND THUNDERSTORM CHANCES WILL END FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS THE UPPER TROUGH AXIS TRANSLATES EAST AND DRIER/SUBSIDENT AIR FILTERS IN. THE REST OF THE WEEK SHOULD BE DRY AND SEASONAL WITH LOWS GENERALLY IN THE 50S AND 60S AND HIGHS IN THE 80S.

LOOKING BEYOND THIS FORECAST PACKAGE...IT APPEARS THAT THE WEATHER
PATTERN WILL BE ON THE ACTIVE SIDE AS WE MOVE INTO THE MIDDLE
HALF OF THE MONTH. THIS WILL BRING MORE COLD FRONTS AND PRECIPITATION
CHANCES.

79

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
300 PM CDT FRI OCT 3 2008

.DISCUSSION...
SHIFT IN PATTERN IS EVIDENT AS SOUTHERLY FLOW INCREASING TEMPERATURES
AND MOISTURE ACROSS THE REGION THIS AFTERNOON. SOME WEAK LIFT IS
APPARENT IN MID LEVEL CLOUDS AND ELEVATED SHOWERS TRYING TO
BREAK OUT ACROSS PORTIONS OF CENTRAL OKLAHOMA AND CENTRAL AND EAST
KANSAS. DOUBT THAT ANY IS REACHING SURFACE AT THIS POINT.

LOW LEVEL JET IS EXPECTED TO START HELPING CONVECTION AROUND MIDNIGHT. AS
IT STRENGTHENS...ELEVATED SHOWERS AND A FEW THUNDERSTORMS ARE EXPECTED
TO DEVELOP AS THIS FEATURE SLIDES EASTWARD OVER THE FORECAST AREA
DURING THE EARLY MORNING HOURS.

THE RAIN SHOULD GRADUALLY DIMINISH AS THE LOW LEVEL JET WEAKENS
DURING DURING THE MORNING HOURS.

STRONG UPPER SYSTEM COMES ASHORE OVER THE WEEKEND AND DIGS A HIGH
AMPLITUDE TROUGH TO THE WEST AND MOVES IT EASTWARD ACROSS THE REGION
DURING THE FIRST HALF OF THE WORK WEEK. THIS WILL CAUSE HIGH CHANCES
FOR SHOWERS AND THUNDERSTORMS. DIFFICULT TO SAY AT THIS
POINT WHAT THE SEVERE THREAT WILL BE BUT WILL DEFINITELY NEED TO
BE WATCHED.

PurdueWx80 wrote:there may be too much low-level ridging along the gulf coast to allow enough moisture into the plains, at least according to the euro.

...SRN HIGH PLAINS AREA...

ENELY TRAJECTORIES ALONG SRN PERIPHERY OF ERN U.S. SURFACE RIDGE HAS
LIMITED BOUNDARY LAYER MODIFICATION ALONG THE NRN GULF. FRIDAY
EVENING RAOBS INDICATED MODEST BOUNDARY LAYER MOISTURE WITH LOW 60S
DEWPOINTS OVER S TX. STRONG SLY GRADIENT FLOW EAST OF LEE TROUGH
WILL CONTRIBUTE TO NWD ADVECTION OF MODIFIED CP AIR THROUGH SRN
PLAINS WARM SECTOR WITH DEWPOINTS GENERALLY IN THE MID TO UPPER 50S.


CURRENT INDICATIONS ARE THAT CONVECTION MAY START EARLY SUNDAY FROM
NM THROUGH NRN PARTS OF W TX WITHIN REGION OF LIFT ASSOCIATED WITH
APPROACHING UPPER JET EXIT REGION. MODEST BOUNDARY LAYER MOISTURE
AND EXPECTED AREAS OF CLOUDS AND ONGOING PRECIPITATION WILL LIKELY
MITIGATE DESTABILIZATION POTENTIAL AND SERVE AS A LIMITING FACTOR
FOR A MORE ROBUST SEVERE THREAT. HOWEVER...SOME BREAKS MAY DEVELOP
OVER CNTRL AND SRN PARTS OF WRN TX AND CLOUDS MAY MIX FROM THE SW AS
THE BOUNDARY LAYER FLOW VEERS TO SWLY WEST OF TROUGH AXIS. STEEPER
MID LEVEL LAPSE RATES AND COOLER TEMPERATURES ALOFT ARE EXPECTED TO
SPREAD OVER MOIST AXIS LATER IN THE DAY...AND THIS WILL CONTRIBUTE
TO AT LEAST MARGINAL INSTABILITY WITH MLCAPE NEAR 500 J/KG POSSIBLE.


POTENTIAL WILL EXIST FOR STORMS TO INTENSIFY DURING THE DAY OVER WRN
TX AS THE ATMOSPHERE GRADUALLY DESTABILIZES. THE AGEOSTROPHIC
CIRCULATION WITHIN UPPER JET EXIT REGION WILL LIKELY MAINTAIN A
30-40 KT SLY LOW LEVEL JET OVER THE SRN AND CNTRL PLAINS. COUPLED
JET STRUCTURE WILL RESULT IN VERTICAL SHEAR PROFILES SUFFICIENT FOR
ORGANIZED STORMS. SEVERE THREAT SHOULD DIMINISH OVERNIGHT AS STORMS
CONSOLIDATE INTO AN MCS AND CONTINUE EAST THROUGH N TX AND OK.

jinftl wrote:Can the countdown to this outbreak go in reverse....i.e.,4 days past the 8 day countdown to the severe outbreak...oh wait, everything has been pushed back 2 days so w are now 4 days past the 8 day countdown plus 2 days.