300  
FXUS64 KLZK 221739  
AFDLZK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LITTLE ROCK AR  
1239 PM CDT FRI OCT 22 2021  
   
AVIATION
 
 
HIGH PRESSURE WILL CONTINUE OVER THE STATE THIS AFTERNOON. IT WILL  
THEN MOVE EAST OF THE AREA TONIGHT AND WINDS WILL BE MORE  
SOUTHERLY SATURDAY. INCREASED MOISTURE COMBINED WITH AN UPPER  
LEVEL SYSTEM WILL BRING A SLIGHT CHANCE OF SHOWERS INTO THE THE  
NORTH PART OF THE STATE IN THE MORNING. VFR CONDITIONS WILL  
CONTINUE.  
 

 
   
PREV DISCUSSION
 
(ISSUED 605 AM CDT FRI OCT 22 2021)  
AVIATION...  
 
VFR CONDITIONS AND A LIGHT AND VARIABLE SURFACE WIND WILL PREVAIL  
TODAY INTO THIS EVENING. MID AND HIGH CLOUDS WILL INCREASE  
TONIGHT, ESPECIALLY IN NORTHERN ARKANSAS. (46)  
 
SHORT TERM...TODAY THROUGH SATURDAY NIGHT  
 
THE PERIOD WILL BEGIN WITH HIGH PRESSURE BUILDING OVER THE REGION  
TODAY. UNDER THE HIGH, THERE WILL BE PLENTY OF SUNSHINE AND  
LIGHT/VARIABLE WINDS. CONDITIONS WILL BE DRY, WITH DEWPOINTS  
MOSTLY IN THE 40S.  
 
THE HIGH WILL RETREAT TO THE EAST FRIDAY NIGHT/SATURDAY. RETURN  
FLOW WILL CRANK UP MOISTURE LEVELS AND PROVIDE MORE CLOUDS.  
DEWPOINTS BY SATURDAY AFTERNOON/EVENING WILL CLIMB INTO THE LOWER  
TO MID 60S. ISOLATED TO SCATTERED SHOWERS ARE ALSO EXPECTED IN  
PARTS OF NORTHERN ARKANSAS.  
 
BY THE TIME THE PERIOD ENDS, A WARM FRONT WILL PASS THROUGH  
THE REGION FROM THE SOUTH, AND IT WILL FEEL MORE LIKE SPRING THAN  
FALL. BREEZY SOUTH WINDS WILL DEVELOP, ESPECIALLY IN PARTS OF THE  
OZARK MOUNTAINS.  
 
TEMPERATURES WILL BE A LITTLE ABOVE SEASONAL TODAY, AND WELL ABOVE  
AVERAGE ON SATURDAY.  
 
LONG TERM...SUNDAY THROUGH THURSDAY  
 
REGARDING THE LONG TERM PD, AN ACTIVE PATTERN WL BE THE MAIN STORY,  
AND IN PARTICULAR, INCREASING CONFIDENCE ON A WINDOW OF SVR WX  
POTENTIAL FOR PORTIONS OF N/WRN AND NRN AR LATE SUN NIGHT.  
 
SUN, LONG TO MEDIUM RANGE GUIDANCE HAS CONTINUED TO CONVERGE ON THE  
EVOLUTION OF A SMALL PERTURBATION INTENSIFYING RAPIDLY UPSTREAM OF  
HIGH AMPLITUDE H500 RIDGING OVER THE CNTRL US. A JET STREAK ON THE  
UPSTREAM PORTION OF THE INITIAL PERTURBATION IS EXPECTED TO  
CONTRIBUTE TO INCREASING DCVA AND H500 HEIGHT FALLS, ALLOWING FOR A  
DEEPENING SHORTWAVE TROF TO QUICKLY EJECT OVER THE CNTRL PLAINS SUN  
AFTERNOON. ANTECEDENT CYCLONIC SFC FLOW OVER THE PLAINS WL RAPIDLY  
DEEPEN INVOF INCREASING DIVERGENCE ALOFT. THROUGH THE DAY SUN, THIS  
SFC LOW WL FOLLOW THE MOVEMENT OF THE UPPER SHORTWAVE, TRACKING E/NE  
ACROSS KS AND INTO MO. ACROSS THE WARM SECTOR OF THIS SFC LOW,  
MOISTURE RETURN IS EXPECTED TO BE VIGOROUS W/ SFC TD'S TOPPING BACK  
OUT IN THE MID 60S OVER THE NATURAL STATE. BY SUN EVENING, A  
SWEEPING COLD FRNT ASSOCIATED W/ THE SFC LOW WL BE APPROACHING THE  
STATE MOVING FROM THE N/W TO THE S/E, AND IS EXPECTED TO BE THE  
PRIMARY DRIVER OF THUNDERSTORM ACTIVITY THROUGH THE NIGHT. THE MOST  
RECENT SUITE OF 00Z GUIDANCE DEPICTS A FAVORABLE PARAMETER SPACE  
OVER THE N/WRN AND NRN PORTION OF AR, PARTICULARLY IN THE 00Z-06Z  
TIMEFRAME SUN NIGHT AS THE FRNT ENTERS THE STATE. DESPITE THE  
NOCTURNAL TIMING, A WINDOW OF SVR WX POTENTIAL WL BE POSSIBLE FOR  
PORTIONS OF N/WRN AND NRN AR LATE SUN NIGHT, AS DEPICTED BY THE NEW  
ENH REGION OUTLINED IN THE D3 SPC CONVECTIVE OUTLOOK. ALL SEVERE  
HAZARDS WL BE POSSIBLE INCLUDING DAMAGING WINDS AND HAIL, AND  
PERHAPS SOME TORNADIC ACTIVITY. SOME CHANGES ARE STILL POSSIBLE TO  
THE FCST, SO BE SURE TO STAY UP TO DATE ON THE LATEST HAZARDOUS WX  
FCST INFORMATION FROM TRUSTED AND RELIABLE SOURCES.  
 
MON, THE EVOLUTION OF THE AFOREMENTIONED COLD FRNT REMAINS IN  
QUESTION B/W THE SOLNS OF THE GFS AND ECMWF, HOWEVER THE CURRENT  
BLENDED TEMP FCST CONT TO REFLECT THE GFS SOLN, IN WHICH THE FRNT  
STALLS OVER THE STATE, AND PIVOTS FROM A S/W TO N/E STANCE INTO A  
MORE W TO E ORIENTATION OVER THE NRN PORTION OF THE FA. AS THE FIRST  
SHORTWAVE QUICKLY DEPARTS TO THE N/E, A LONGWAVE TROF OVER THE PAC-  
N/W IS EXPECTED TO PROGRESS E/WRD ACROSS THE CONT DIVIDE. A RINSE  
AND REPEAT PATTERN WL UNFOLD, W/ ANOTHER STRONG SFC LOW TRACKING E-  
N/E OVER KS AND MO, AND ANOTHER TAILING COLD FRNT APPROACHING THE  
STATE. WIDESPREAD RAIN AND THUNDERSTORMS ARE ANTICIPATED W/ THIS  
NEXT SYSTEM DURING THE TUES/WED TIMEFRAME, HOWEVER MODEL  
DISCREPANCIES BECOME MORE ENHANCED AND CONFIDENCE DECREASES  
REGARDING SVR WX POTENTIAL...WL CONT TO WATCH THIS SECOND SYSTEM AS  
IT NEARS SHORTER RANGE GUIDANCE.  
 
A PRIMARY DIFFERENCE IS APPARENT B/W THE TWO SYSTEMS THOUGH...GIVEN  
MUCH STRONGER UPPER-LVL DYNAMICS IN THE SECOND TROF, E.G. A BROADER  
LONGWAVE AND GREATER FETCH OF N/WRLY TROPOSPHERIC FLOW, A BIG  
COOLDOWN LOOKS TO BE ON THE WAY BY MID-WEEK NEXT WEEK. IN THE WAKE  
OF THE COLD FRNT, DIURNAL TRENDS WL RETURN TO MORE SEASONAL VALUES,  
ALONG W/ PREVAILING DRY WX AS SFC MOISTURE BOTTOM OUT AND SFC HIGH  
PRESSURE SETTLES OVER THE REGION.  
 

 
   
LZK WATCHES/WARNINGS/ADVISORIES
 
NONE.  

 
 

 
 
AVIATION...51  
 
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