Monday, April 16, 2007

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 170050
SWODY1
SPC AC 170047

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0747 PM CDT MON APR 16 2007

VALID 170100Z - 171200Z

..NO SVR TSTM AREAS FORECAST...

..FOUR CORNERS REGION INTO SRN/CNTRL HIGH PLAINS...

ISOLATED TO WIDELY SCATTERED TSTMS ARE ONGOING THIS EVENING OVER
PORTIONS OF UT/CO INTO NRN NM IN ADVANCE AND TO THE N OF MID AND
UPPER-LEVEL LOW TRANSLATING SLOWLY EWD THROUGH AZ. 00Z ABQ/GJT
SOUNDINGS ARE LIKELY REPRESENTATIVE OF THERMODYNAMIC ENVIRONMENT
ACROSS THE REGION...FEATURING A DEEP AND WELL MIXED BOUNDARY
LAYER...STEEP LOW TO MID-LEVEL LAPSE RATES AND SBCAPES OF 200-400
J/KG. THE STRONGEST VERTICAL SHEAR IS PRESENT OVER THE CNTRL INTO
SRN HIGH PLAINS IN ASSOCIATION WITH BELT OF STRONGER MID AND
HIGH-LEVEL FLOW PRECEDING THE UPPER TROUGH.

AS OF 0030Z...THE MOST INTENSE CONVECTIVE DEVELOPMENT WAS OCCURRING
OVER THE FRONT RANGE INVOF PUB WERE SOME MARGINALLY SEVERE HAIL HAS
RECENTLY BEEN REPORTED. WHILE ISOLATED/SCATTERED TSTMS WILL LIKELY
CONTINUE OVERNIGHT...THESE MORE INTENSE STORMS SHOULD DIMINISH IN
INTENSITY BY 02-03Z AS BOUNDARY LAYER COOLS AND LOW-LEVEL LAPSE
RATES WEAKEN. OTHER STORMS /LIKELY ELEVATED/ MAY DEVELOP OVER
PORTIONS OF W TX LATER TONIGHT IN ASSOCIATION WITH INTENSIFYING WAA
REGIME ALONG LLJ AXIS.

.MEAD.. 04/17/2007

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DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 162000
SWODY1
SPC AC 161958

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT MON APR 16 2007

VALID 162000Z - 171200Z

..NO SVR TSTM AREAS FORECAST...

..CNTRL ROCKIES...

THUNDERSTORMS HAVE RECENTLY EXPANDED IN AREAL COVERAGE AND INTENSITY
ALONG NRN PERIPHERY OF UPPER LOW...ESPECIALLY JUST NORTH OF THE
4-CORNERS REGIN OF UT/CO. THIS ACTIVITY IS QUITE ROBUST IN
NATURE...PARTICULARLY DUE TO VERY STEEP LAPSE RATE ENVIRONMENT AND
MODEST DEEP LAYER SHEAR. LATEST DIAGNOSTIC DATA INDICATES MLCAPE
VALUES ON THE ORDER OF 250-500J/KG WHERE DEEPEST ASCENT/MOISTENING
IS OBSERVED OVER THE HIGHER TERRAIN. LATEST THINKING IS HAIL WILL
ACCOMPANY MOST OF THE STRONGER CORES...MOST OF WHICH SHOULD BE
SUB-TO-MARGINALLY SEVERE IN NATURE. STRONG DIURNAL INFLUENCES
SHOULD MODULATE STRENGTH OF THESE UPDRAFTS...THUS INTENSITIES SHOULD
WANE LATER THIS EVENING WITH BOUNDARY LAYER COOLING.

DOWNSTREAM...THUNDERSTORMS MAY DEVELOP/SPREAD INTO THE SRN HIGH
PLAINS REGION LATER TONIGHT AS LLJ INCREASES IN RESPONSE TO THIS
EWD-MOVING UPPER SYSTEM. RECOVERING/MODIFYING WARM SECTOR ACROSS TX
WILL LIMIT OVERALL INSTABILITY/SEVERE THREAT OVER THIS AREA.

.DARROW.. 04/16/2007

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MESO: Mesoscale Discussion 0511

ACUS11 KWNS 161900
SWOMCD
SPC MCD 161900
COZ000-UTZ000-162100-

MESOSCALE DISCUSSION 0511
NWS STORM PREDICTION CENTER NORMAN OK
0200 PM CDT MON APR 16 2007

AREAS AFFECTED...CNTRL/SRN UT AND WRN CO

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 161900Z - 162100Z

LATEST WATER VAPOR IMAGERY SHOWS THE CENTER OF AN UPR LOW OVER NWRN
AZ WITH SEVERAL SHORTWAVE TROUGHS SPINNING AROUND THE LOW IN THE GRT
BASIN REGION. ONE SUCH IMPULSE WAS MOVING NWWD VCNTY THE FOUR
CORNERS REGION AND HAS BEEN IMPETUS FOR INCREASING TSTMS OVER THE
HIGHER TERRAIN OF ECNTRL/SERN UT AND WRN CO. H5 TEMPERATURES AROUND
MINUS 20 DEG C...HEATING AND LARGE SCALE ASCENT WILL CONTINUE TO BE
FAVORABLE FOR TSTMS THROUGH EARLY EVE. TSTMS WILL MOVE OFF THE
HIGHER TERRAIN TO THE WNW AND GIVEN DEEP...RELATIVELY DRY SUB-CLOUD
LAYER...SVR/DAMAGING WINDS MAY OCCUR ALONG WITH HAIL IN THE STRONGER
STORMS.

.RACY.. 04/16/2007

..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GJT...SLC...

39391207 39640930 38030844 37320960 37491236

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DAY2SVR: Nws Storm Prediction Center Norman Ok

ACUS02 KWNS 161728
SWODY2
SPC AC 161726

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1226 PM CDT MON APR 16 2007

VALID 171200Z - 181200Z

..THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE SRN
PLAINS/LOWER MS VALLEY...

..SOUTHERN PLAINS/LOWER MS VALLEY...

NEXT IN A SERIES OF STRONG UPPER TROUGHS WILL EJECT AT A RATHER LOW
LATITUDE ACROSS THE SRN ROCKIES INTO OK/TX WITH MUCH OF THIS REGION
EXPECTED TO REMAIN ON CYCLONIC SIDE OF JET STREAK. VERY COLD MID
LEVEL TEMPERATURES...H5 AOB MINUS 20C...WILL SPREAD ACROSS MOST OF
NCNTRL TX/SRN OK DURING THE AFTERNOON HOURS STEEPENING MID LEVEL
LAPSE RATES. IT ALSO APPEARS STRONG BOUNDARY LAYER HEATING WILL
DEVELOP WEST OF I-35...SOUTH OF THE RED RIVER WITHIN FAVORABLE POST
DRYLINE ENVIRONMENT. THIS SHOULD ENHANCE CONVECTIVE POTENTIAL TO
THE N-E OF ADVANCING SFC LOW/WIND SHIFT.

LATEST MODEL GUIDANCE APPEARS QUITE FAVORABLE FOR EARLY CONVECTIVE
INITIATION WITHIN THE STRONG WARM ADVECTION ZONE ACROSS THE TX
PANHANDLE INTO WRN OK. THIS ACTIVITY WILL BE ELEVATED IN NATURE AND
SUFFICIENTLY UNSTABLE ENOUGH FOR MARGINAL SEVERE HAIL DEVELOPMENT.
HOWEVER...WIDESPREAD CLOUDS AND PRECIPITATION WILL SUPPRESS
STRONGEST INSTABILITY TO THAT REGION NEAR THE RED RIVER...SWD INTO
ECNTRL TX WHERE SFC-BASED CAPE SHOULD BE AOA 1000 J/KG BY 21Z.
AFTERNOON CONVECTION AHEAD OF SFC LOW/DRY LINE SHOULD BE
SUFFICIENTLY SHEARED FOR SUPERCELLS...ESPECIALLY ALONG AN AXIS FROM
NWRN TX TO NEAR DAL. LARGE HAIL CERTAINLY APPEARS TO BE THE
GREATEST RISK DUE TO STEEP LAPSE RATES WITHIN THIS RAPIDLY
RECOVERING WARM SECTOR. CLUSTERS OF STRONG/ISOLATED SEVERE
THUNDERSTORMS SHOULD SPREAD DOWNSTREAM INTO THE LOWER MS VALLEY
DURING THE OVERNIGHT HOURS WITH GRADUAL WEAKENING EXPECTED DUE TO
INTERACTION WITH MORE STABLE AIR.

.DARROW.. 04/16/2007

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DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 161630
SWODY1
SPC AC 161627

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1127 AM CDT MON APR 16 2007

VALID 161630Z - 171200Z

..NO SVR TSTM AREAS FORECAST...

..EASTERN CO...
DEEP UPPER LOW OVER EASTERN AZ IS FORECAST TO MOVE SLOWLY EASTWARD
INTO THE SOUTHERN ROCKIES TONIGHT. SOUTHWEST FLOW ALOFT AND STRONG
HEATING WILL INDUCE LEE CYCLOGENESIS OVER SOUTHEAST CO...WITH
SURFACE TROUGH EXTENDING SOUTHWARD ACROSS EASTERN NM. VERY MINIMAL
LOW LEVEL MOISTURE IS EXPECTED TO PRECLUDE MORE THAN VERY ISOLATED
THUNDERSTORM DEVELOPMENT FROM CO/NM BORDER SOUTHWARD.
HOWEVER...BACKED LOW LEVEL WINDS ACROSS EASTERN CO WILL ENHANCE
UPSLOPE FLOW AND HELP CONVECTIVE INITIATION THIS AFTERNOON. STORMS
WILL LIKELY BEGIN OVER THE FOOTHILLS OF SOUTHERN CO AND SPREAD
NORTHEASTWARD INTO THE ADJACENT HIGH PLAINS. FORECAST SOUNDINGS
SUGGEST SOME POTENTIAL FOR GUSTY WINDS AND HAIL IN STRONGER CELLS.

..WESTERN CO...
STRONG DAYTIME HEATING AND STEEP MID LEVEL LAPSE RATES WILL HELP
YIELD AT LEAST MARGINAL AFTERNOON INSTABILITY ACROSS WESTERN CO INTO
THE FOUR CORNERS REGION. SHORTWAVE TROUGH NOW OVER EASTERN AZ WILL
ROTATE NORTHWARD INTO REGION THIS AFTERNOON...AIDING IN THE
DEVELOPMENT OF SCATTERED THUNDERSTORMS. GUSTY WINDS AND HAIL MAY
OCCUR IN STRONGER CELLS BEFORE WEAKENING AFTER DARK.

.HART/JEWELL.. 04/16/2007

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DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 161244
SWODY1
SPC AC 161242

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0742 AM CDT MON APR 16 2007

VALID 161300Z - 171200Z

..NO SVR TSTM AREAS FORECAST...

..SYNOPSIS...
AN INTENSE/OCCLUDING LOW NEAR THE NRN NJ COAST HAS REACHED PEAK
INTENSITY AND WILL MOVE LITTLE WHILE FILLING TODAY. IN THE WAKE OF
THIS DEEP CYCLONE...A STRONG COLD FRONT HAS SWEPT THROUGH THE ENTIRE
GULF OF MEXICO BASIN...LEAVING A RELATIVELY DRY/STABLE AIR MASS
ACROSS THE ERN CONUS. FARTHER W...A CLOSED LOW OVER WRN AZ/SW UT
THIS MORNING WILL PROGRESS EWD TO NM AND SRN CO TONIGHT.
ASCENT/HEIGHT FALLS DOWNSTREAM FROM THIS LOW WILL INDUCE
CYCLOGENESIS IN THE LEE OF THE SRN ROCKIES...AND A WEAK LOW IS
EXPECTED TO MOVE SLOWLY EWD FROM ERN NM INTO W TX BY TUESDAY
MORNING.

..SRN HIGH PLAINS LATE TODAY...
AIR MASS MODIFICATION IS UNDERWAY ACROSS THE SW/WRN GULF BASIN...BUT
SUBSTANTIAL MOISTURE RETURN INTO THE SRN HIGH PLAINS IS NOT EXPECTED
THIS SOON. THEREFORE...INSTABILITY WILL BE DRIVEN BY STEEP LAPSE
RATES WITH THE MID LEVEL LOW AND DAYTIME HEATING...WITH RESIDUAL
BOUNDARY LAYER DEWPOINTS ONLY IN THE 20S NEAR THE FRONT RANGE IN
NM...AND 35-40 F FROM E/SE CO INTO W TX. THE POOR MOISTURE WILL
LIMIT THE MAGNITUDE OF THE INSTABILITY AND THUNDERSTORM
COVERAGE...THOUGH INVERTED-V PROFILES WITH STRONG DEEP LAYER SPEED
SHEAR COULD SUPPORT ISOLATED HIGH-BASED STORMS WITH GUSTY WINDS AND
SMALL HAIL LATE THIS AFTERNOON INTO EARLY TONIGHT. THE MODIFYING
GULF AIR MASS WILL BEGIN TO REACH NW TX LATE TONIGHT...AND MAY HELP
SUSTAIN A FEW SMALL /ELEVATED/ THUNDERSTORM CLUSTERS OVERNIGHT.

..ERN UT/WRN CO TODAY...
STEEP MID LEVEL LAPSE RATES ARE PRESENT IN 12Z SOUNDINGS AT GJT AND
SLC...WITH SUFFICIENT LOW-MID LEVEL MOISTURE FOR DEEP CONVECTION.
ASCENT DOWNSTREAM FROM THE CO VALLEY UPPER LOW...ALONG WITH SOME
DAYTIME HEATING...SHOULD PROMOTE THE DEVELOPMENT/CONTINUATION OF
WIDELY SCATTERED THUNDERSTORMS THROUGH THE DAY. THOUGH VERTICAL
SHEAR WILL BE RELATIVELY WEAK THIS AREA...THE STRONGER STORMS COULD
PRODUCE SMALL HAIL.

.THOMPSON/TAYLOR.. 04/16/2007

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DAY48SVR: Nws Storm Prediction Center Norman Ok

ACUS48 KWNS 160900
SWOD48
SPC AC 160900

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0400 AM CDT MON APR 16 2007

VALID 191200Z - 241200Z

..DISCUSSION...
EXTENDED MODELS REMAIN CONSISTENT IN BRINGING A LARGE UPPER
TROUGH/CLOSED LOW OUT OF THE ROCKIES AND INTO THE PLAINS DAYS 6-7
/SAT. APR 21-SUN. APR. 22/...ALONG WITH PRONOUNCED SURFACE LOW
DEVELOPMENT. WITH SELY INFLUX OF GULF MOISTURE EXPECTED IN ADVANCE
OF THIS SYSTEM...EXPECT AMPLE INSTABILITY WITHIN DEVELOPING WARM
SECTOR...WHILE INTENSITY OF THE UPPER FEATURE SHOULD PROVIDE
SUFFICIENT SHEAR FOR SUPERCELLS. THEREFORE...IT STILL APPEARS
LIKELY THAT A RELATIVELY WIDESPREAD SEVERE EVENT CAN BE EXPECTED FOR
THE UPCOMING WEEKEND...AND THUS WILL MAINTAIN A SEVERE THREAT AREA
ACROSS THE CENTRAL CONUS FOR DAY 6 AND INTO DAY 7. SUFFICIENT MODEL
DIFFERENCES BEGIN TO OCCUR BY DAY 8...PRECLUDING THE INCLUSION OF A
DAY 8 AREA ATTM.

.GOSS.. 04/16/2007

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MESO: Mesoscale Discussion 0510

ACUS11 KWNS 160755
SWOMCD
SPC MCD 160755
NYZ000-PAZ000-161030-

MESOSCALE DISCUSSION 0510
NWS STORM PREDICTION CENTER NORMAN OK
0255 AM CDT MON APR 16 2007

AREAS AFFECTED...PARTS OF NE PA...AND CNTRL/NERN NEW YORK STATE

CONCERNING...HEAVY SNOW

VALID 160755Z - 161030Z

HEAVY SNOW MAY CONTINUE ACROSS PARTS OF REGION THROUGH MID
MORNING...BUT HEAVIEST HOURLY RATES MAY BEGIN TO DIMINISH SHORTLY.

CENTER OF DEEP SURFACE CYCLONE NOW APPEARS TO BE INLAND OF NEW
JERSEY COASTAL AREAS INTO THE VICINITY OF FORT DIX...WHERE SURFACE
PRESSURES ARE ALREADY 3-4 MB LOWER THAN PROGGED BY MOST MODELS...AND
RAPID 2 HOUR SURFACE PRESSURE FALLS PERSIST. HOWEVER...MODEL
GUIDANCE GENERALLY SUGGESTS PEAK INTENSITY WILL BE REACHED WITHIN
NEXT FEW HOURS...BEFORE PRESSURES NEAR LOW CENTER LEVEL OFF
BY/SHORTLY AFTER 12Z. LATEST RUC GUIDANCE INDICATES THAT MID-LEVEL
FRONTOGENETIC FORCING...IN LAYER WITH TEMPERATURES FAVORABLE FOR
DENDRITIC ICE CRYSTAL GROWTH...ALREADY IS WEAKENING ALONG AN AXIS
NORTH/NORTHWEST OF LOW CENTER...ACROSS NORTHWEST PENNSYLVANIA
THROUGH CENTRAL NEW YORK. CONSEQUENTLY...SNOW RATES IN ROUGHLY 100
MI WIDE BAND EXTENDING ACROSS THIS REGION SEEM LIKELY TO DIMINISH
DURING THE 08-10Z TIME FRAME. HOWEVER...LOW-LEVEL FRONTAL FORCING
MAY MAINTAIN RATES UP TO AROUND AN INCH PER HOUR THROUGH
12-14Z...NEAR/JUST WEST OF THE WATERTOWN/SYRACUSE/ITHACA
AREAS...WHERE THERMODYNAMIC PROFILES WILL REMAIN COLD ENOUGH FOR
SNOW.

.KERR.. 04/16/2007

..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...BTV...BGM...BUF...

41557625 42127703 43347707 44147667 44737605 44807536
44437502 43527552 42197584 41777583 41597597 41557609

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DAY3SVR: Nws Storm Prediction Center Norman Ok

ACUS03 KWNS 160723
SWODY3
SPC AC 160722

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0222 AM CDT MON APR 16 2007

VALID 181200Z - 191200Z

..NO SVR TSTM AREAS FORECAST...

..SYNOPSIS...
UPPER TROUGH MOVING ACROSS THE WRN CONUS WILL REMAIN
STRONG/WELL-DEFINED...WHILE TAKING ON A NEGATIVE TILT AS IT
APPROACHES THE CENTRAL/NRN HIGH PLAINS THROUGH THE END OF THE
PERIOD. MEANWHILE...TROUGH MOVING ACROSS THE SOUTHEAST WILL
CONTINUE TO WEAKEN...AND SHOULD EVENTUALLY BECOME ABSORBED WITHIN
LARGER-SCALE CYCLONIC FLOW EVOLVING OVER THE ERN CONUS WITH TIME.

WHILE SHOWERS AND SCATTERED THUNDERSTORMS SHOULD ACCOMPANY BOTH OF
THESE FEATURES...DEGREE OF INSTABILITY SHOULD GREATLY LIMIT ANY
SEVERE POTENTIAL.

.GOSS.. 04/16/2007

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DAY2SVR: Nws Storm Prediction Center Norman Ok

ACUS02 KWNS 160552
SWODY2
SPC AC 160551

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1251 AM CDT MON APR 16 2007

VALID 171200Z - 181200Z

..THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF N CENTRAL AND
NERN TX...

..SYNOPSIS...
THUNDERSTORMS ARE FORECAST ACROSS THE NWRN CONUS AND INTO THE
ROCKIES AHEAD OF LARGE UPPER TROUGH MOVING ONSHORE OVER THE WEST.
HOWEVER...GREATER CONVECTIVE THREAT SHOULD ACCOMPANY THE WEAKENING
UPPER LOW MOVING FROM THE SRN ROCKIES ACROSS TX/OK THROUGH THE
AFTERNOON...AND THEN INTO THE TN VALLEY REGION BY THE END OF THE
PERIOD.

AT THE SURFACE...A STRONG COLD FRONT ACCOMPANYING THE WRN U.S.
TROUGH SHOULD MOVE ACROSS THE GREAT BASIN/WRN AND CENTRAL MT THROUGH
THE PERIOD. MEANWHILE...A MUCH WEAKER SURFACE PATTERN -- CONSISTING
OF JUST A WEAK LOW -- SHOULD ACCOMPANY THE WEAKENING S CENTRAL CONUS
FEATURE.

..N CENTRAL/NERN TX...
WHILE PRECIPITATION/EMBEDDED THUNDERSTORMS SHOULD BE ONGOING EARLY
IN THE PERIOD WITHIN WARM ADVECTION REGIME...MORE VIGOROUS
CONVECTION IS FORECAST DURING THE AFTERNOON. DEWPOINTS IN THE UPPER
50S TO LOW 60S BENEATH COLD MID-LEVEL AIR SPREADING EWD ACROSS THE
SRN PLAINS /H5 TEMPERATURES -18 TO -20 C/ SHOULD YIELD INSTABILITY
/500 TO 1000 J/KG MEAN-LAYER CAPE/ SUFFICIENT FOR LOW-TOPPED STORMS.


WHILE SHEAR THROUGH THE LOWER HALF OF THE CLOUD DEPTH WILL LIKELY
REMAIN MARGINAL ACROSS MUCH OF THE REGION...STEEP-LAPSE RATES -- AND
THUS THE POTENTIAL FOR RAPID UPDRAFT ACCELERATION -- SHOULD BE
SUFFICIENT FOR SCATTERED STRONG/MULTICELL STORMS. ATTM...IT APPEARS
THAT THE DEGREE OF SEVERE THREAT -- MAINLY IN THE FORM OF HAIL --
WARRANTS THE INTRODUCTION OF A SLIGHT RISK.

.GOSS.. 04/16/2007

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DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 160547
SWODY1
SPC AC 160545

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1245 AM CDT MON APR 16 2007

VALID 161200Z - 171200Z

..NO SVR TSTM AREAS FORECAST...

..SYNOPSIS...

AMPLIFIED YET PROGRESSIVE LARGE-SCALE PATTERN WILL EXIST THROUGH THE
DAY ONE PERIOD WITH THE PRIMARY FEATURE OF INTEREST BEING MID AND
UPPER-LEVEL LOW WHICH WILL TRANSLATE EWD FROM THE LOWER CO VALLEY
INTO THE SRN HIGH PLAINS BY TUESDAY MORNING. IN THE
LOW-LEVELS...LEE TROUGH WILL INTENSIFY THROUGH THE PERIOD OVER THE
SRN HIGH PLAINS IN RESPONSE TO SWRN U.S. UPPER SYSTEM. FARTHER
N...COLD FRONT WILL PUSH SWD THROUGH THE NRN PLAINS AND UPPER MS
VALLEY...WHILE ALONG THE E COAST INTENSE CYCLONE WILL DEVELOP FROM
THE VICINITY OF LONG ISLAND EWD INTO THE ATLANTIC.

..SRN HIGH PLAINS...

FRONTAL SURGE ATTENDANT TO POWERFUL ERN U.S. SYNOPTIC SYSTEM HAS
EFFECTIVELY PUSHED S THROUGH GULF BASIN WITH RICHER BOUNDARY LAYER
MOISTURE CONFINED TO THE YUCATAN PENINSULA AND POINTS S. AS
SUCH...CONVECTIVE INSTABILITY WILL REMAIN QUITE LIMITED INVOF LEE
TROUGH THIS AFTERNOON AND EVENING...AND THIS SHOULD TEND TO MITIGATE
ANY ORGANIZED SEVERE WEATHER THREAT.

NONETHELESS...EXPECT TSTMS TO INITIALLY DEVELOP TODAY WITHIN STEEP
LAPSE RATE ENVIRONMENT OVER THE HIGHER TERRAIN OF CO/NM WITHIN ZONE
OF LARGE-SCALE FORCING FOR ASCENT IN ADVANCE OF UPPER SYSTEM. THIS
ACTIVITY SHOULD GENERALLY MOVE/DEVELOP EWD INTO THE ADJACENT HIGH
PLAINS WITH ADDITIONAL...ISOLATED STORM DEVELOPMENT ALSO POSSIBLE BY
EARLY EVENING ALONG LEE TROUGH.

VERTICAL SHEAR PROFILES WILL BECOME INCREASINGLY SUPPORTIVE OF
ORGANIZED SEVERE STORMS...INCLUDING SUPERCELLS AS MID-LEVEL FLOW
INCREASES TO 50-60 KT. HOWEVER...THIS POTENTIAL WILL LIKELY BE
TEMPERED BY THE MARGINAL CONVECTIVE INSTABILITY...THOUGH SOME OF THE
MORE INTENSE STORMS WILL BE CAPABLE OF LOCALLY STRONG WIND GUSTS
/GIVEN THE DEEP...WELL MIXED BOUNDARY LAYER/ AND SOME HAIL.

.MEAD/TAYLOR.. 04/16/2007

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