263  
FXUS64 KLZK 182303 AAA  
AFDLZK  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE LITTLE ROCK AR  
603 PM CDT MON MAR 18 2019  
   
DISCUSSION
 
 
UPDATED TO INCLUDE THE 00Z AVIATION DISCUSSION BELOW...  
 

 
   
AVIATION
 
 
EXPECT THE VFR CONDITIONS TO PERSIST THROUGH THE PERIOD. HIGH  
PRESSURE WILL SHIFT TO THE EAST OVERNIGHT INTO TUE...WITH WINDS  
BECOMING MORE SRLY.  
 

 
   
PREV DISCUSSION
 
(ISSUED 257 PM CDT MON MAR 18 2019)  
 
SHORT TERM...TONIGHT THRU WEDNESDAY...  
 
NORTHWESTERLY FLOW ALOFT WILL CONTINUE TONIGHT, AS AN OMEGA PATTERN  
STARTS TO TAKE SHAPE ACROSS THE WESTERN US. AN ENERGETIC BUT COMPACT  
LOW WILL BE DROPPING DOWN OUT OF CANADA, ACROSS THE PLAINS, AND WILL  
SPIN DOWN INTO ARKANSAS AT THE END OF THE SHORT TERM.  
 
ORDINARILY I WOULD BE A BIT MORE CONCERNED ABOUT A SYSTEM LIKE  
THIS IN MARCH, BUT THERE ARE GOING TO BE SOME SIGNIFICANT  
LIMITATIONS TO LOW LEVEL MOISTURE AND INSTABILITY...WHICH HAS BEEN  
A RECURRING THEME WITH MANY OF THE PAST SYSTEMS.  
 
THE SURFACE PATTERN REMAINS FIRMLY UNDER HIGH PRESSURE AT THE  
MOMENT, AND THE HIGH WILL SLIDE TO THE EAST AND ALLOW A SOUTHERLY  
FLOW TO DEVELOP BY TOMORROW AFTERNOON. HOWEVER, THE SOUTHERLY FLOW  
DOES NOT EXTEND VERY FAR TO THE SOUTH OF ARKANSAS, AND THERE WILL  
NOT BE ANY SUBSTANTIAL CONNECTION TO GULF MOISTURE. AS THE SYSTEM  
APPROACHES WEDNESDAY, A COLD FRONT WILL BE PUSHING INTO THE AREA.  
 
WHILE THERE WILL BE QUITE A BIT OF LIFT AVAILABLE WITH THIS  
SYSTEM, THE THERMODYNAMICS AND MOISTURE LEVELS ARE NOT VERY  
IMPRESSIVE. FOR THE TIME BEING I AM LEAVING THE EXISTING MENTION  
OF SHOWERS...SANS THUNDER - IN THE FORECAST GRIDS FOR NOW.  
 
LONG TERM...WEDNESDAY NIGHT THRU SUNDAY NIGHT...  
 
TO BEGIN THE PERIOD, H500 OMEGA HIGH WILL BE SITUATED OVER THE  
NRN PLAINS. ON THE ERN PERIPHERY OF THE HIGH, AN EMBEDDED IMPULSE  
WILL BE MOVING THROUGH THE FLOW TRAVERSING NE AR. AT THE SURFACE,  
A WEAK FRONTAL BOUNDARY WILL BE SWEEPING THROUGH THE STATE  
PROVIDING WEAK LIFT TO PROMOTE THE DEVELOPMENT OF LIGHT  
PRECIPITATION. BEST POP CHANCES WILL RESIDE ACROSS NERN PORTIONS  
OF THE STATE WHERE AMOUNTS OF QUARTER OF AN INCH OR LESS ARE  
EXPECTED. HEADING INTO THURSDAY THE OMEGA HIGH AXIS SHIFTS FURTHER  
E TOWARDS AR. SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION  
FROM THE PLAINS HOWEVER, THE AIR MASS BEHIND THE BOUNDARY WILL  
REMAIN FAIRLY MILD BUT WILL PROVIDE A RE-ENFORCING SHOT DRIER AIR  
VIA LOWER DEW POINTS.  
 
ON FRIDAY, THE UPPER LEVEL RIDGE AXIS BEGINS SHIFTING E OF AR, AT  
THE SURFACE, HIGH PRESSURE BEGINS TO MOVE AWAY FROM THE REGION AS  
SERLY WINDS RETURN. OUT W, A CLOSED UPPER LOW BEGINS TO EJECT  
TOWARDS THE ROCKIES. BEYOND FRIDAY EVENING, MODEL GUIDANCE BECOMES  
MORE UNCERTAIN TO HOW THE UPPER LOW OVER THE DESERT SW EVOLVES ON  
ITS EWRD TREK. BY LATE SATURDAY, A SHEARED AXIS SETS UP BETWEEN  
UPPER RIDGING OVER THE TN VALLEY AND TROUGHING OVER THE PLAINS.  
SWERLY FLOW INCREASES ACROSS THE REGION WITH BROAD ASCENT  
OVERSPREADING FROM SW TO NE. MOISTURE ADVECTION WILL INCREASE ACROSS  
WRN PORTIONS OF THE CWA INITIALLY BEFORE SPREADING EWRD AS MOISTURE  
IS PULLED NWRD INTO THE SURFACE LOW OVER THE PLAINS. SHOWERS AND  
THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE WEEKEND WITH THE HELP  
OF COMPACT IMPULSES PIVOTING AROUND THE BASE OF THE TROUGH AND  
THROUGH THE MEAN SW TO NE ORIENTED FLOW. TEMPERATURES WILL REMAIN IN  
THE 60S AND 70S FOR HIGHS AND LOWS RANGING FROM THE MID 30S TO MID  
50S.  
 

 
   
LZK WATCHES/WARNINGS/ADVISORIES
 
NONE.  

 
 

 
 
AVIATION...62  
 
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