Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 010701
SWODY2
SPC AC 010700

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CST SUN MAR 01 2015

VALID 021200Z - 031200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS WILL BE POSSIBLE ON
MONDAY AND MONDAY NIGHT ACROSS THE ARK-LA-TEX AND EASTERN OKLAHOMA
INTO ARKANSAS...SOUTHERN MISSOURI...AND FAR WESTERN TENNESSEE.
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS WILL ALSO BE POSSIBLE
EARLY MONDAY ACROSS A SMALL PART OF SOUTHERN CALIFORNIA...AND INTO
THE LOWER COLORADO RIVER VALLEY AND WESTERN ARIZONA MONDAY
AFTERNOON.

...SYNOPSIS...
A STRONG MID-UPPER-LEVEL RIDGE WILL REMAIN ANCHORED FROM THE GULF OF
MEXICO INTO THE WRN CARIBBEAN.  HEIGHTS ARE EXPECTED TO RISE ACROSS
MUCH OF THE ERN HALF OF THE U.S. IN THE WAKE OF A TROUGH MOVING
THROUGH THE NERN STATES AND DEPARTING THE NRN ATLANTIC COAST MONDAY
AFTERNOON.  MEANWHILE...A BLOCKING RIDGE WILL REMAIN LOCATED WEST OF
THE PACIFIC COAST.  A SHORTWAVE TROUGH WILL AMPLIFY SSEWD ACROSS
CENTRAL CANADA INTO THE NORTH-CENTRAL STATES...WHILE A WEAKER TROUGH
DEVELOPS SWD FROM THE WA/ORE COAST FORMING A CLOSED LOW JUST OFF THE
SRN CA COAST BY 12Z TUESDAY.  THIS EVOLUTION WILL RESULT IN
DISLODGING THE DAY 2 SRN CA TROUGH NEWD THROUGH THE SWRN STATES TO
CENTRAL HIGH PLAINS /ERN CO TO WRN NEB/.

...ERN OK/ARKLATEX TO SRN MO/WRN TN...
SLY LOW-LEVEL FLOW IS EXPECTED TO STRENGTHEN FROM CENTRAL AND
EASTERN TX THROUGH ERN OK...THE OZARKS INTO ERN KS AND THE LOWER MO
VALLEY.  THIS INCREASE IN LOW-LEVEL WINDS SHOULD BE THE GREATEST
MONDAY NIGHT AS 60-90-METER HEIGHT FALLS OCCUR ACROSS OK TO THE
LOWER MO VALLEY AHEAD OF THE EJECTING SRN CA TROUGH AND THE SSEWD
MOVING CENTRAL CANADA TROUGH.  THIS WILL RESULT IN SUBSTANTIAL
LOWER-TROPOSPHERIC MOISTENING AND WARM-AIR ADVECTION WITH THESE
FACTORS BEING GREATER ABOVE THE SURFACE.  A LARGE SURFACE
HIGH-PRESSURE AREA WILL SHIFT EWD FROM THE CENTRAL UNITED
STATES...THOUGH SURFACE TRAJECTORIES ACROSS THE SOUTH-CENTRAL STATES
SHOULD NOT BECOME SLY UNTIL LATE IN THE FORECAST PERIOD WHEN A
SURFACE LOW TRACKS FROM ERN CO INTO NWRN KS.  THE LACK OF GREATER
BOUNDARY-LAYER MOISTENING WILL LIMIT THE POTENTIAL FOR PARCELS TO
BECOME SURFACE-BASED WITH STRONGER DESTABILIZATION /MUCAPE OF
100-200 J PER KG/ OCCURRING ABOVE THE SURFACE.  FORECAST SOUNDINGS
SUGGEST MOST PARCELS SHOULD BE ROOTED AROUND 850 MB...THOUGH
CONFIDENCE IN TSTM COVERAGE IS LOW GIVEN THE FORECAST PRESENCE OF A
MIDLEVEL WARM LAYER.  HOWEVER...THE INCREASE IN LOW-LEVEL MOISTENING
AND WAA MONDAY NIGHT SUGGESTS PARCELS SHOULD BE ABLE TO OVERCOME THE
WARMER 700-MB TEMPERATURES TO SUPPORT ELEVATED TSTMS.

...PORTIONS OF CENTRAL AND SRN CA...
A LINGERING POTENTIAL FOR MAINLY ISOLATED TSTMS WILL EXIST ACROSS
PRIMARILY THE COASTAL AREAS OF FAR SRN CA MONDAY MORNING INTO THE
EARLY AFTERNOON BEFORE A SRN CA SHORTWAVE TROUGH EJECTS NEWD.  IF
THE WRN WA/ORE SHORTWAVE TROUGH TRACKS MORE SWD THROUGH WRN CA
INSTEAD OF OFFSHORE...THEN FORCING FOR ASCENT AND STEEPENING LAPSE
RATES COULD SUPPORT ISOLATED TSTMS ACROSS COASTAL AREAS OF CENTRAL
CA.  LATEST GUIDANCE TENDS TO FAVOR THE OFFSHORE TRACK...AND THUS
WILL NOT INCLUDE A GENERAL TSTM AREA AT THIS TIME ALONG THE CENTRAL
CA COAST.

...LOWER CO RIVER VALLEY INTO WRN AZ...
THE COLD MIDLEVEL TEMPERATURES AND FORCING FOR ASCENT ATTENDANT TO
THE SRN CA TROUGH MOVING ACROSS THE LOWER CO RIVER VALLEY AND AZ
MONDAY AFTERNOON WILL SUPPORT DIURNALLY DRIVEN TSTMS...AS LAPSE
RATES STEEPEN.

..PETERS.. 03/01/2015



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