376  
FXUS63 KTOP 242026  
AFDTOP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TOPEKA KS  
326 PM CDT TUE MAY 24 2016  
   
SHORT TERM
 
(THIS EVENING THROUGH WEDNESDAY)  
ISSUED AT 324 PM CDT TUE MAY 24 2016  
 
A FAMILIAR SYNOPTIC PATTERN IS SEEN IN THE 19Z WATER VAPOR IMAGERY.  
WITH A MEAN TROUGH STILL OVER THE WEST AND NORTHERN ROCKIES,  
SOUTHWESTERLY FLOW ALOFT REMAINS OVER THE CENTRAL PLAINS. A SURFACE  
LOW WAS AGAIN ANALYZED OVER THE OK PANHANDLE WITH A DRYLINE  
EXTENDING SOUTH THROUGH WEST TX. OUTFLOW FROM MORNING STORMS HAS  
MUDDLED UP THE SURFACE PATTERN OVER NORTHEAST KS AND THE BETTER  
MOISTURE CONVERGENCE IS APPEARS TO BE OVER SOUTHWEST KS BETWEEN THE  
SURFACE LOW AND THE OUTFLOW BOUNDARY OVER SOUTHERN KS.  
 
A LOT OF THIS FORECAST IS BASED ON EXPECTED PERSISTENCE OF THE  
PATTERN AND PREVIOUS NIGHTS. THINK THAT STORMS WILL ONCE AGAIN  
DEVELOP OVER SOUTHWESTERN KS AND CONGEAL INTO AN MCS MOVING ACROSS  
EASTERN KS TONIGHT. THE HRRR/ARW/NMM SHOW A BOWING MCS DEVELOPING  
THIS EVENING AND MOVE IT ACROSS THE FORECAST AREA BY THE LATE  
EVENING. 0-6KM SHEAR REMAINS RATHER MARGINAL AROUND 30KT SO THE MAIN  
CONCERNS WITH THE STORMS WILL BE DAMAGING WINDS, HAIL AND LOCALIZED  
FLASH FLOODING. HAVE LIKELY POPS GOING TONIGHT, BUT CONFIDENCE IS  
ONLY MEDIUM AS SOME OF THE MODELS STILL SHOW VARIOUS TRACKS TO THE  
MCS. POPS TAPER DOWN DURING THE MORNING WEDNESDAY AS MODELS MOVE THE  
STORMS THROUGH EARLIER IN THE NIGHT. ALTHOUGH IF AN MCV IS SLOW TO  
MOVE EAST, THERE COULD BE SOME LINGERING PRECIP LATE IN THE MORNING.  
 
LOWS TONIGHT SHOULD BE IN THE LOWER TO MID 60S WITH RAIN COOLED AIR  
HELPING TO COOL TEMPS MORE SO THAN THEY WOULD BE WITHOUT PRECIP.  
HIGHS WEDNESDAY ARE FORECAST TO BE IN THE LOWER AND MID 80S AS  
MODELS ADVECT WARMER AIR INTO EASTERN KS WITH 850MB TEMPS WARMING TO  
AROUND 22C AND 700MB TEMPS BETWEEN 8 AND 10C. BECAUSE OF THIS,  
FORECAST SOUNDINGS SHOW AN ELEVATED MIXED LAYER CAPPING THE BOUNDARY  
LAYER THROUGH MUCH OF THE AFTERNOON. SO THE QUESTION BECOMES WHETHER  
THERE IS ENOUGH CONVERGENCE ALONG THE DRYLINE TO FORCE STORMS  
BECAUSE LARGE SCALE FORCING AGAIN APPEARS TO BE WEAK AT BEST. MOST  
GUIDANCE SEEMS TO KEEP THE BOUNDARY LAYER CAPPED AS THEY DO NOT  
GENERATE MUCH QPF IN THE AFTERNOON, SO HAVE KEPT SOME SMALL POPS IN  
THE FORECAST FOR WEDNESDAY AFTERNOON ON THE SMALL CHANCE A STORM  
DEVELOPS.  
   
LONG TERM
 
(WEDNESDAY NIGHT THROUGH TUESDAY)  
ISSUED AT 324 PM CDT TUE MAY 24 2016  
 
WEDNESDAY NIGHT FRIDAY...  
 
CONVECTIVE CHANCES BY EARLY EVENING WILL BE DEPENDENT ON WHAT  
MESOSCALE BOUNDARIES WILL BE PRESENT FROM ANY CONVECTION EARLIER IN  
THE DAY. OTHERWISE THE DRYLINE AND FRONT WILL BE LOCATED WEST OF THE  
FORECAST AREA. THERE IS NOT MUCH IN THE WAY OF UPPER SUPPORT,  
HOWEVER THE MODELS SUGGEST THAT THERE MAY BE A WEAK WAVE MOVING OUT  
OF WESTERN KANSAS INTO NEBRASKA WEDNESDAY NIGHT. INSTABILITY,  
MOISTURE AND SHEAR WILL BE SUFFICIENT FOR A FEW SEVERE STORMS WITH  
HAIL AND WIND THE MAIN HAZARDS AND A LOW PROBABILITY FOR TORNADOES.  
THURSDAY MAY START OUT DRY AS MODELS MOVE OFF AN MCS WELL EAST BY  
12Z THURSDAY. THE MODELS HAVE SLOWED THE EJECTION OF THE MAIN ENERGY  
EJECTING OUT OF THE WESTERN TROUGH, BUT DO EJECT A LEAD SHORTWAVE  
OUT INTO THE PLAINS THURSDAY AFTERNOON AND EVENING. FORECAST  
SOUNDINGS SHOW STEEPENING LAPSE RATES AND INCREASING SHEAR AROUND 30  
TO 35 KTS TOWARD 00Z FRIDAY ALONG WITH MLCAPE AROUND 2500 J/KG.  
EXPECT THUNDERSTORMS TO DEVELOP ALONG THE FRONT AND DRYLINE THEN  
MOVE NORTHEAST AND EAST ACROSS THE CWA DURING THE EVENING AND  
OVERNIGHT HOURS. HAVE MAINTAINED HIGHER PRECIPITATION CHANCES FOR  
THURSDAY NIGHT AND FRIDAY AS THE UPPER LEVEL TROUGH ADVANCES OUT  
INTO THE PLAINS. FORCING WILL ALSO BE AIDED BY LEFT EXIT REGION OF  
THE UPPER JET ACROSS CENTRAL AND NORTH CENTRAL KANSAS ON FRIDAY. ANY  
ONGOING PRECIPITATION WILL LIKELY LEAVE MESOSCALE BOUNDARIES ACROSS  
PARTS OF THE AREA BY FRIDAY AFTERNOON.  
 
FRIDAY NIGHT THROUGH TUESDAY...  
 
THE ACTIVE SPRING PATTERN WILL CONTINUE THROUGH THE EXTENDED PERIOD.  
FRIDAY NIGHT AN UPPER LEVEL TROUGH ACROSS THE FOUR-CORNERS REGION  
WILL EJECT NORTHEASTWARD INTO THE CENTRAL PLAINS. A STRONG VORT-MAX  
WILL WILL EJECT ACROSS THE FORECAST AREA FRIDAY EVENING INTO  
SATURDAY MORNING, BRINGING LIKELY CHANCES FOR THUNDERSTORMS ACROSS  
THE ENTIRE AREA. STRONG TO SEVERE THUNDERSTORMS WILL ALSO BE  
POSSIBLE AS SUFFICIENT CAPE AND SHEAR WILL BE IN PLACE. THE  
REMAINDER OF THE PERIOD WILL CONSIST OF SOUTHWEST FLOW ALOFT AND  
EMBEDDED WEAK UPPER-LEVEL WAVES. WITH THE PLENTIFUL BOUNDARY LAYER  
MOISTURE THAT WILL BE IN PLACE, HAVE AT LEAST SLIGHT CHANCE POPS  
THROUGH THE REMAINDER OF THE PERIOD.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)  
ISSUED AT 1239 PM CDT TUE MAY 24 2016  
 
ANOTHER CHALLENGING FORECAST FOR THE PERIOD WITH TIMING OF  
CONVECTION AND CEILINGS. VFR CONDITIONS ARE EXPECTED THIS AFTERNOON  
INTO THE EARLY EVENING BEFORE A COMPLEX OF STORMS IS EXPECTED TO  
MOVE THROUGH THE AREA OVERNIGHT. TIMING OF THIS POTENTIAL SYSTEM IS  
STILL UNCERTAIN, BUT A BEST GUESS HAS BEEN CONVEYED IN THE TAF  
THROUGH VCTS FROM 02-03Z TO 11-12Z. A MAJORITY OF MODELS ARE  
BRINGING LOWER MVFR/IFR CEILINGS IN WITH THE COMPLEX AND THROUGH THE  
MORNING, HOWEVER, BELIEVE THEY HAVE BEEN OVERDOING THE LOW CLOUD THE  
PAST COUPLE DAYS SO HAVE INCLUDED A SCATTERED LOW DECK WITH BKN VFR  
CEILINGS FOR NOW.  
 

 
   
TOP WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SHORT TERM...WOLTERS  
LONG TERM...BAERG/53  
AVIATION...HELLER  
 
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