SPC AC 220550
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1150 PM CST SUN MAR 21 2004
   
   VALID 221200Z - 231200Z
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 W RBL 45 NNW MFR
   30 WSW DLS 45 SW PDT 55 NNW BNO 50 NNE 4LW 60 S 4LW 35 NE SAC 40 W
   SAC 60 W RBL.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 SE HSI 20 NW BIE
   35 N FNB 30 WSW LWD 50 S P35 40 NNE SGF 20 NE JLN 20 WSW CNU 35 WNW
   EMP 25 N SLN 35 SE HSI.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 SW TUS 20 E PHX 20
   SSW CDC 45 NNW DPG 35 ENE EVW 35 NE RKS 15 W RWL 35 ENE CAG 15 NW
   EGE 20 NNW GUC 50 WNW ALS 50 NNW LVS 50 N ROW 20 SE HOB 65 SW SJT 40
   SE DRT.
   
   ...NO SVR TSTM AREAS FORECAST...
   
   ...SYNOPSIS...
   UPPER FLOW PATTERN WILL DEAMPLIFY SOMEWHAT ON MONDAY AS COLD UPPER
   TROUGH ACROSS THE ERN STATES BEGINS TO ACCELERATE EWD OFF THE
   ATLANTIC COAST MONDAY NIGHT.  MEANWHILE...UPPER RIDGE WILL BEGIN TO
   FLATTEN AS DISTURBANCES EJECT NEWD FROM BASE OF THE GULF OF AK UPPER
   LOW AND ACROSS THE PAC NW.  THE UPPER LOW WITHIN SRN STREAM ACROSS
   NRN MEXICO WILL MOVE INTO THE SRN ROCKIES/SRN HIGH PLAINS BY MONDAY
   NIGHT. AT THE SURFACE...COLD FRONT THAT MOVED WELL SOUTH IN WAKE OF
   THE ERN STATES TROUGH WILL BEGIN TO REDEVELOP NWD ACROSS THE
   SRN/CNTRL PLAINS BY EARLY TUESDAY.
   
   ...PAC NW...
   OPERATIONAL ETA SUGGESTS THAT AIR MASS WILL BE MUCH MORE UNSTABLE
   ACROSS NRN CA INTO PARTS OF ORE THAN EITHER THE GFS OR NGM IMPLY. 
   BASED ON THE ARRIVAL OF UPSTREAM IMPULSE AND PRESENCE OF STEEP LAPSE
   RATES OVER THE PAC NW DURING PEAK HEATING...IT IS POSSIBLE THAT A
   FEW OF THE TCU OVER THE MOUNTAINS MAY GROW INTO TSTMS LATE MONDAY
   AFTERNOON.  STRONGER UPDRAFTS MAY YIELD GUSTY WINDS OR HAIL...BUT
   CONFIDENCE ON ANY SUSTAINED ORGANIZED DEEP CONVECTION IS LIMITED
   GIVEN THE UNCERTAINTY OF THE MAGNITUDE OF LOW-MIDLEVEL MOISTURE THAT
   WILL BE PRESENT.  
   
   ...FOUR CORNERS AREA/SRN ROCKIES/SWRN TX MOUNTAINS...
   PROFILES HAVE MOISTENED ACROSS THE REGION OWING TO THE INJECTION OF
   HIGH LEVEL MOISTURE ALONG NRN PERIPHERY OF THE MEXICAN UPPER LOW AND
   INCREASING LOW LEVEL MOISTURE BEHIND BACKDOOR COLD FRONT.  DAYTIME
   HEATING ALONG WITH THE STEEP MID TROPOSPHERIC LAPSE RATES WILL
   CONTRIBUTE TO MARGINALLY UNSTABLE ENVIRONMENT AND A FEW TSTM WILL BE
   POSSIBLE.  ACTIVITY WILL LARGELY BE DIURNALLY DRIVEN AND DECREASE IN
   THE EVENING.
   
   ...LOWER MO VLY...
   PROSPECTS FOR ELEVATED NOCTURNAL TSTMS WILL INCREASE ACROSS PARTS OF
   THE LOWER MO VLY...MOST LIKELY AFTER 23/09Z.  WARM ADVECTION IS
   EXPECTED TO INTENSIFY AS SWLY LLJ INCREASES MONDAY NIGHT.  WHILE
   STEEPER LAPSE RATES WILL SPREAD NEWD...SOME UNCERTAINTY EXISTS
   REGARDING THE MAGNITUDE OF MOISTENING AND RESULTANT INSTABILITY. 
   OPERATIONAL MODELS TIME SERIES FROM PAST SEVERAL RUNS INDICATE SOME
   CONSISTENCY IN CONVECTIVE PCPN DEVELOPING IN THE 09-12 UTC TIME
   FRAME. THIS PROVIDES ENOUGH CONFIDENCE TO INCLUDE A SMALL GENERAL
   TSTM RISK.
   
   ..RACY/TAYLOR.. 03/22/2004
   
   ...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 FOR 1300Z