180   
FXUS10 KWNH 031627  
PMDHMD  
  
MODEL DIAGNOSTIC DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
1226 PM EDT FRI APR 03 2020  
  
VALID APR 03/1200 UTC THRU APR 07/0000 UTC  
  
...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR  
INGEST...  
  
12Z MODEL EVALUATION WITH PREFERENCES AND CONFIDENCE  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
   
..OVERALL PATTERN ACROSS THE CONUS  
  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
PREFERENCE: GENERAL MODEL BLEND THROUGH 05.12Z; GFS/ECMWF BLEND  
AFTER  
CONFIDENCE: AVERAGE  
  
LARGE SCALE SYNOPTIC PATTERN ACROSS THE CONUS CURRENTLY FEATURES  
LARGE GYRE OVER ALBERTA WHILE THE OFFSHORE NORTHEAST U.S. SYSTEM  
BEGINS TO PULL AWAY. OVER THE COMING 2-3 DAYS, SEVERAL IMPULSES  
WILL WORK THROUGH THAT LARGE SYSTEM OVER THE NORTHERN ROCKIES.  
MEANWHILE, EASTERN PACIFIC ENERGY WILL EVOLVE INTO A LARGE CLOSED  
LOW OFF THE CALIFORNIA COAST BY THE END OF THE FORECAST PERIOD.  
FINALLY, WEAK SOUTHERN STREAM ENERGY WILL MOVE THROUGH THE  
SOUTHERN PLAINS, TEXAS GULF COAST REGION AND BE THE FOCUS FOR  
LOCALLY HEAVY RAINFALL POTENTIALLY.  
  
OVERALL, MODELS SHOW FAIRLY GOOD AGREEMENT WITH THE 500 MB PATTERN  
OVER THE NEXT 3 DAYS ACROSS THE CONUS. THIS INCLUDES THE SEVERAL  
PIECES OF ENERGY ROTATING THE BASE OF THE LARGE CLOSED LOW OVER  
ALBERTA. FOR THE LEADING SHORTWAVE OVER THE NORTHERN PLAINS, THE  
LATEST 12Z GUIDANCE SHOWS VERY GOOD AGREEMENT.  
  
DIFFERENCES IN THE SOUTHERN STREAM ENERGY ACROSS TEXAS ARE MORE  
TIED TO MESOSCALE FEATURES AND INGREDIENTS BUT THE SIGNIFICANT  
MOISTURE/INSTABILITY RETURN DOES PRESENT THE POTENTIAL FOR HEAVY  
RAINFALL/FLASH FLOODING. BUT OVERALL THE 12Z MASS FIELDS ARE IN  
GOOD SHAPE SUCH THAT A GENERAL MODEL BLEND IS PREFERRED.  
  
FINALLY, OVER THE WESTERN U.S., A PAIR OF SHORTWAVES OFF THE  
PACIFIC NW COAST WILL GRADUALLY EVOLVE INTO A LARGE CLOSED LOW BY  
DAY 3. FOR THE INITIAL SHORTWAVE, A GENERAL MODEL BLEND IS  
SUFFICIENT. AS THE SECONDARY, LARGER SHORTWAVE MOVES INTO THE AREA  
AND CLOSES OFF, THERE REMAINS SOME LATITUDINAL SPREAD IN THE  
LATEST GUIDANCE. OVER THE LAST SEVERAL MODEL CYCLES, THE GFS/ECMWF  
REMAIN THE MORE CONSISTENT AND MIDDLE GROUND APPROACH AND FOR THIS  
CYCLE, A BLEND OF THE TWO DETERMINISTIC RUNS ARE PREFERRED.  
  
MODEL TRENDS AT WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML  
500 MB FORECASTS AT WWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML  
  
TAYLOR  
  
  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.


The Nexlab HPC Page

Main Text Page