370  
FXUS02 KWNH 270633  
PREEPD  
 
PRELIMINARY EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
233 AM EDT FRI MAY 27 2016  
 
VALID 12Z MON MAY 30 2016 - 12Z FRI JUN 03 2016  
   
..PATTERN OVERVIEW
 
 
VIGOROUS SHORTWAVE ENERGY DIVING INTO THE NORTHWEST EARLY NEXT  
WEEK IS EXPECTED TO AMPLIFY WHILE PROGRESSING DOWNSTREAM ACROSS  
THE NORTHERN TIER OF THE NATION...POTENTIALLY CLOSING OFF AN UPPER  
LOW OVER THE NORTH CENTRAL U.S. BY THE MIDDLE OF THE WEEK. MEAN  
RIDGING WILL SLIDE INTO THE WESTERN U.S. BEHIND THE AMPLIFYING  
UPPER TROUGH...AND THE FOCUS IN THE EASTERN U.S. WILL BE WITH A  
DISTURBANCE NORTH OF THE BAHAMAS CURRENTLY BEING MONITORED BY THE  
NATIONAL HURRICANE CENTER.  
 
   
..MODEL EVALUATION/PREFERENCES
 
 
MODEL GUIDANCE CONTINUES TO SHOW A LARGE AMOUNT OF UNCERTAINTY  
WITH THE EVOLUTION OF THE AMPLIFYING UPPER TROUGH PROGRESSING  
THROUGH THE NORTHERN TIER OF THE NATION NEXT WEEK. THE GFS/GEFS  
MEAN HAVE CONSISTENTLY BEEN ON THE SLOWER SIDE OF MODEL SPREAD  
WITH THE UPPER TROUGH AND ASSOCIATED COLD FRONT...WHILE THE ECMWF  
CONTINUES TO ADVERTISE A MUCH FASTER SOLUTION. WITHOUT A CLEAR  
TREND IN PREVIOUS MODEL AND ENSEMBLE RUNS...THE WPC FORECAST  
STAYED IN-BETWEEN THE SLOWER GFS AND FASTER ECMWF...WHICH WAS  
SUPPORTED BY THE UKMET AND CMC.  
 
A SECOND AREA OF UNCERTAINTY IN THE FORECAST IS LATE NEXT WEEK  
ACROSS THE WESTERN U.S....WHERE COMPLICATIONS IN THE EASTERN  
PACIFIC LEAD TO A LARGE AMOUNT OF SPREAD IN THE TIMING AND  
STRENGTH OF AN UPPER TROUGH POTENTIALLY LIFTING INTO THE PACIFIC  
NORTHWEST. FOR NOW...THE WPC FORECAST RELIED ON FAIRLY AGREEABLE  
ENSEMBLE MEAN GUIDANCE TOWARDS THE LATER HALF OF NEXT WEEK.  
 
IN REGARDS TO THE DISTURBANCE CURRENTLY NORTH OF THE  
BAHAMAS...MODELS ARE GENERALLY IN GOOD AGREEMENT WITH TRACKING THE  
SYSTEM WEST/NORTHWESTWARD TOWARDS THE SOUTHEAST COAST...BUT PLEASE  
REFER TO THE NATIONAL HURRICANE CENTER FOR THE LATEST INFORMATION.  
 
 
   
..SENSIBLE WEATHER HIGHLIGHTS
 
 
A MOIST AIRMASS IN PLACE ACROSS THE CENTRAL U.S. SHOULD ALLOW FOR  
HEAVY RAIN AND THUNDERSTORMS AHEAD/ALONG A COLD FRONT CROSSING THE  
GREAT PLAINS AND MISSISSIPPI VALLEY NEXT WEEK...ESPECIALLY ACROSS  
TEXAS WHERE THE TAIL END OF THE BOUNDARY WILL BE SLOW TO PRESS  
SOUTHWARD. UPPER RIDGING IN THE WEST SHOULD KEEP CONDITIONS WARM  
AND DRY FROM THE WEST COAST THE ROCKIES...AND THE DISTURBANCE  
CURRENTLY NORTH OF THE BAHAMAS COULD BRING MULTIPLE DAYS OF RAIN  
AND THUNDERSTORM ACTIVITY TO THE SOUTHEAST AND CAROLINAS NEXT  
WEEK.  
 
GERHARDT  
 
 
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page