SPC AC 190557
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1157 PM CST FRI FEB 18 2005
   
   VALID 191200Z - 201200Z
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 SW ONP 20 E ONP 30
   S SLE 40 ESE EUG 30 NE MFR 45 W MHS 15 ESE RBL 45 NNE FAT 55 NW DRA
   50 W P38 25 WSW BCE 40 SW 4HV 40 WNW GJT 30 E GJT 45 S GUC 20 NW SAF
   40 WSW ROW 25 ENE CNM 15 SSE MAF 25 SE DRT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 ENE PBF 60 N HOT
   40 N JLN 10 SSE MHK 40 WSW CNK HLC 45 S MCK 20 WNW MCK 30 NNE MCK 15
   NNW HSI 15 ESE OMA 10 NNW LWD 10 W UIN 20 N SLO 25 N HOP 30 SSE CKV
   40 N MSL 15 WNW MSL 45 ENE PBF.
   
   ...NO SVR TSTM AREAS FORECAST...
   
   ...SYNOPSIS...
   LARGE SCALE SPLIT FLOW REGIME WITH COMPLEX CYCLONE ALONG THE CA
   COAST AND DOWNSTREAM CONFLUENCE OVER THE PLAINS/MS VALLEY WILL
   BECOME MORE ZONAL THROUGH THE WEEKEND. A FAST MOVING SRN STREAM
   DISTURBANCE...EMANATING FROM THE WEST COAST LOW...WILL PASS OVER THE
   ROCKIES AND EMERGE OVER THE PLAINS THROUGH EARLY SUNDAY.
   MEANWHILE...ANOTHER STRONG SHORT WAVE TROUGH DEVELOPING SWD OVER WRN
   CANADA...WILL PASS ACROSS THE PACIFIC NORTHWEST AND START TO MERGE
   WITH THE NRN PORTION OF THE WEST COAST TROUGH/LOW. BROAD UPPER LEVEL
   RIDGING WILL EXIST ALONG/INLAND ACROSS THE GULF COAST REGION. ASIDE
   FROM A FAST MOVING SHORT WAVE TROUGH BRUSHING NRN NEW ENGLAND...
   RISING HEIGHTS ARE EXPECTED FROM THE MIDWEST/GREAT LAKES TO THE MID
   ATLANTIC.
   
   MAIN FEATURES DRIVING TSTM DEVELOPMENT THIS PERIOD WILL BE THE WEST
   COAST TROUGHS...AS WELL AS THE SRN STREAM SHORT WAVE MOVING EAST
   FROM THE FOUR CORNERS/INTERMOUNTAIN WEST TO THE PLAINS.
   
   ...CA/AZ...
   ONLY WEAK HEIGHT FALLS ARE ANTICIPATED ACROSS CA/AZ LATER TODAY IN
   THE WAKE OF THE MORE WELL-DEFINED IMPULSE NOW MOVING OVER UT.
   NONETHELESS...COLD MID LEVEL TEMPERATURES AND POCKETS OF STRONGER
   DIURNAL HEATING AND/OR GREATER MOISTURE...ESPECIALLY OVER THE DESERT
   AREAS/NEAR THE CA COAST...WILL CONTRIBUTE TO THE DEVELOPMENT OF
   MUCAPE OF AT LEAST 250-500 J/KG. WITH WEAK TO NEUTRAL LARGE SCALE
   FORCING...PRIMARY FACTORS DRIVING TSTM DEVELOPMENT WILL BE WEAK
   OROGRAPHIC AND ISENTROPIC ASCENT COUPLED WITH WEAKENING INHIBITION.
   MODEST SHEAR AND SUFFICIENT INSTABILITY DEVELOPING ACROSS SRN AZ
   DURING THE AFTERNOON COULD SUPPORT A FEW STRONG TSTMS CAPABLE OF
   PRODUCING ONE OR TWO HAIL/WIND EVENTS. ACTIVITY ALONG THE CA COASTAL
   AREAS WILL LIKELY BE LESS ORGANIZED DUE TO WEAKER CLOUD BEARING
   SHEAR. HOWEVER...ISOLATED TO WIDELY SCATTERED TSTMS IN THESE AREAS
   COULD ALSO PRODUCE SMALL HAIL GIVEN COLD TEMPERATURES ALOFT.
   
   ...MO RIVER VALLEY TO MID MS VALLEY LATE...
   A LEE-SIDE CYCLONE WILL DEEPEN OVER CO AND MOVE EAST ALONG
   STRENGTHENING WARM FRONT ACROSS THE CNTRL PLAINS/MO RIVER VALLEY IN
   RESPONSE TO STRONG UPPER WAVE. LOW LEVEL MOISTURE TRANSPORT INTO THE
   LOW AND FRONTAL ZONE WILL INTENSIFY THROUGH THE DAY BENEATH ELEVATED
   MIXED LAYER AIR MASS CHARACTERIZED BY STEEP MID LEVEL LAPSE RATES OF
   7-8 C/KM. STRONG CAPPING WILL LIKELY SUPPRESS TSTM DEVELOPMENT OVER
   MUCH OF THE SRN PLAINS THROUGH THE EVENING. HOWEVER...COMBINATION OF
   STRONG FORCING AND MOISTURE TRANSPORT ON THE NOSE OF THE LLJ AFTER
   DARK...AND STEEPENING LAPSE RATES ON THE NRN EDGE OF THE CAPPING
   INVERSION ACROSS THE CNTRL PLAINS...SHOULD PROMOTE ELEVATED TSTM
   DEVELOPMENT FROM NRN KS/SRN NE ESEWD TO MO/AR AREAS IN THE 03-06Z
   TIME FRAME. STORM UPDRAFTS WILL BE ROOTED WELL ABOVE THE BOUNDARY
   LAYER BUT WILL BE ON THE NRN EDGE OF A PLUME OF POTENTIALLY STRONG
   INSTABILITY WHERE MUCAPE VALUES MAY APPROACH 500 J/KG. GIVEN
   STRENGTH OF LARGE SCALE FORCING FOR ASCENT AND STEEP LAPSE RATES...A
   FEW CELLS COULD PRODUCE HAIL INTO EARLY SUNDAY MORNING.
   
   ..CARBIN.. 02/19/2005
   
   ...NOTICE...
   FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
   LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
   GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
   HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
   INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
   
   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z