918  
FXUS63 KTOP 172020  
AFDTOP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TOPEKA KS  
320 PM CDT SUN MAY 17 2026  
   
KEY MESSAGES
 
 
- SCATTERED STORMS ARE EXPECTED TO DEVELOP ALONG A DRYLINE/COLD  
FRONT ACROSS NORTH-CENTRAL LATE THIS AFTERNOON AND INTO THE EVENING.  
LOCALIZED FLOODING, LARGE HAIL (UP TO 2.5 INCHES) AND DAMAGING WINDS  
(60-70 MPH) WILL BE POSSIBLE.  
 
- WIDESPREAD SEVERE THUNDERSTORMS ARE STILL EXPECTED MONDAY  
AFTERNOON AND EVENING ACROSS EASTERN KANSAS. STORMS ARE EXPECTED TO  
BE RATHER INTENSE WITH ALL MODES OF SEVERE WEATHER POSSIBLE (HAIL UP  
TO 2-4", DAMAGING WINDS TO 70 MPH, AND A FEW TORNADOES - SOME  
STRONG).  
 
- A FLOOD WATCH HAS BEEN ISSUED FOR AREAS NORTH OF I-70 THROUGH  
TUESDAY MORNING. HEAVY RAINFALL FROM SEVERAL ROUNDS OF THUNDERSTORMS  
COULD YIELD IN 2-4 INCHES OF RAINFALL WITH LOCALLY HIGHER AMOUNTS.  
 
- STORMS EXIT THE AREA BY EARLY TUESDAY MORNING WITH A MUCH COOLER  
AIR MASS MOVING INTO THE REGION FOR THE REMAINDER OF THE WEEK.  
SHOWER AND STORM CHANCES RETURN THURSDAY-SATURDAY TO THE REGION.  
 

 
   
DISCUSSION
 
 
ISSUED AT 318 PM CDT SUN MAY 17 2026  
 
ANOTHER VOLATILE ENVIRONMENT IS SETTING UP FOR STRONG THUNDERSTORMS  
THIS AFTERNOON ACROSS THE CENTRAL PLAINS JUST AHEAD OF A DEEPENING,  
POSITITEVELY-TILTED UPPER TROUGH IN THE ROCKIES. PERSISTENT PVA INTO  
THE CENTRAL PLAINS HAS FURTHER DEEPENED A 995 MB SURFACE LOW ACROSS  
NORTHWESTERN KANSAS WITH A TIGHT PRESSURE GRADIENT EXTENDING TO ITS  
EAST ACROSS KANSAS. GUSTY WINDS AND STRONG LOW-LEVEL MOISTURE  
TRANSPORT HAVE BECOME APPARENT THIS AFTERNOON OVER EASTERN KANSAS AS  
MIXING AND DIURNAL HEATING HAS SLOWLY MIXED OUT CLOUD COVER. BY THE  
LATER AFTERNOON HOURS, DIURNAL HEATING AND LOW-LEVEL MOISTURE  
TRANSPORT WILL PUSH MLCAPE VALUES INTO THE 3000-3500 J/KG RANGE WITH  
MODEST DEEP SHEAR. INITIAL STORM DEVELOPMENT CAN BE EXPECTED TO  
DEVELOP NEAR THE TRIPLE POINT REGION IN NORTH-CENTRAL KANSAS AND  
ALONG THE DRYLINE TO THE SOUTH ACROSS CENTRAL KANSAS. STORMS WILL  
LIKELY STRENGTHEN QUICKLY GIVEN THE STEEP ML AND LL LAPSE RATES.  
INITIAL THREATS WITH STORMS WILL BE VERY LARGE HAIL (UP TO 2-3 INCHES  
IN DIAMETER) AND WINDS UP TO 60-70 MPH. BY THE EARLY EVENING, A 0-1  
KM BULK SHEAR VECTORS AND SLIGHT BACKING OF SURFACE WINDS WILL HELP  
TO ELONGATE HODOGRAPHS ACROSS THE THE WARM SECTOR AND HELP TO  
INCREASE THE TORNADO THREAT WITHIN STORMS. THAT SAID, THE LACK OF  
DEEP SHEAR THIS FAR EAST OF THE MAIN UPPER LEVEL WAVE SEEMS TO BE  
MODEST AT BEST (20-35 KNOTS). THIS INDICATES THE POTENTIAL FOR  
STORMS TO LACK THE STRUCTURE TO MAINTAIN THEMSELVES FOR LONG PERIODS.  
BETTER SHEAR VALUES FOR LONG AND SUSTAINED SUPERCELLS SEEMS TO STAY  
NORTH AND WEST OF THE AREA THIS EVENING. TAKING ALL OF THIS INTO  
ACCOUNT, THE BEST WINDOW FOR STRONG TO SEVERE STORMS SEEMS TO BE FROM  
6PM TO MIDNIGHT TONIGHT. ELEVATED CONVECTION WILL TRACK EAST THROUGH  
THE OVERNIGHT HOURS AIDED BY OUTFLOW BOUNDARIES AND ISENTROPIC  
ASCENT WITHIN THE LLJ. AS MOST CONVECTION WILL REMAIN ELEVATED AFTER  
12 AM TONIGHT, MAIN HAZARDS WILL BE LARGE HAIL AND AN OCCASIONAL WIND  
GUST TO 50-60 MPH. TRAINING AND BACKBUILDING OF CONVECTION IN THE  
EARLY MORNING HOURS OF MONDAY MAY ALSO POSE A LOCALIZED FLOODING  
CONCERN WITH AREAS PICKING UP A QUICK 1-2 INCHES WITH LOCALLY HIGHER  
AMOUNTS TO 3-4 REMAINING A POSSIBILITY.  
 
ATTENTION QUICKLY TURNS TO MONDAY AS THIS APPEARS TO BE THE DAY THAT  
WILL POSE THE MOST WIDESPREAD AND HIGH-END RISK FOR SEVERE WEATHER.  
LINGERING RAIN AND THUNDERSTORMS WILL EXIT INTO MISSOURI BY THE MID  
MORNING MONDAY LEAVING MUCH OF FAR EASTERN KANSAS BLANKETED WITH  
STRATUS. THERE HAVE BEEN HINTS THAT AN OUTFLOW BOUNDARY WILL REMAIN  
ACROSS THE AREA FROM MORNING CONVECTION. THIS COULD BECOME A FOCAL  
POINT IN CONVECTION LATER IN THE AFTERNOON SO WILL NEED TO MONITOR  
THIS AS CONVECTION EXITS IN THE MORNING. THROUGH THE DAY, THE LONG  
WAVE TROUGH THAT HAS REMAINED STALLED OVER THE CENTRAL ROCKIES  
EJECTS OVER THE CENTRAL PLAINS, TAKING ON A NEGATIVE TILT ACROSS  
KANSAS. LOW-LEVEL MESOSCALE FEATURES WILL RESPOND TO THE UPPER  
TROUGH'S EASTWARD PUSH WITH A SURFACE CYCLONE ENTERING CENTRAL AND  
NORTH-CENTRAL KS BY PEAK HEATING HOURS. AHEAD OF THE SURFACE LOW, A  
VERY UNSTABLE WARM SECTOR CHARACTERIZED BY UPPER 60 DEGREE TDS,  
UPPER 80 AND LOW 90 DEGREE SURFACE TS WILL BE IN PLACE. ALOFT, A 50-  
60 KNOT 500 MB JET WILL OVERSPREAD CENTRAL AND EASTERN KANSAS WITH  
COOLING MID-LEVEL TEMPERATURES AND INTENSE DIVERGENCE ALOFT. THIS  
WILL PUSH MLCAPE VALUES INTO THE 4000-4500 J/KG. RAP AND HRRR  
ANALYSIS HAS MLCIN AND SBCIN ERODING BY 18-20Z IN CENTRAL AND NORTH-  
CENTRAL KANSAS, JUST AHEAD OF THE SURFACE TRIPLE POINT. CONVECTIVE  
INITIATION ALONG THE DRYLINE/COLDFRONT IN THE 20-22Z TIMEFRAME HAS  
BEEN NOTED BY HREF ANALYSIS. THERE IS A SMALL CHANCE THAT ISOLATED  
CELLS GO UP AHEAD OF THE FRONTAL BOUNDARY, ESPECIALLY IF THERE IS AN  
OUTFLOW BOUNDARY STALLED OUT OVER THE REGION, BUT CONFIDENCE IN THIS  
OCCURRING IS LOW AT THE MOMENT. NOT MUCH HAS CHANGED IN TERMS OF  
OVERALL THREATS AS WE ARE STILL LOOKING AT VERY LARGE HAIL (UP TO 2-  
4" IN SIZE), DAMAGING WINDS (70-80 MPH) AND TORNADOES, SOME POSSIBLY  
STRONG.  
 
THE MAIN QUESTION AT THIS POINT IN TIME IS THE OVERALL  
EVOLUTION IN STORMS MONDAY EVENING. IF STORMS CAN MOVE OFF THE  
BOUNDARY AND BECOME ISOLATED, THIS WOULD POSE A GREATER RISK FOR  
STRONG TORNADOES, AND VERY LARGE HAIL. THE OTHER SCENARIO WOULD BE  
FOR STORMS TO FORM ALONG THE BOUNDARY AND GROW UPSCALE. WHILE STORMS  
WILL STILL BE VERY INTENSE IN THE UPSCALE SCENARIO, STORM  
INTERACTIONS MAY LIMIT THE INTENSITY OF STORMS A BIT KEEPING LARGE  
HAIL, DAMAGING WINDS AND A FEW TORNADOES POSSIBLE. GIVEN LOTS OF  
CURVATURE IN LOW-LEVEL HODOGRAPHS IN THE WARM SECTOR, IT SEEMS LIKELY  
THAT SEVERAL WELL-ESTABLISHED SUPERCELLS WILL SEPARATE FROM THE  
FRONT AND FOLLOW THE RIGHT VECTOR THAT TAKES THE STORM MORE  
EAST/NORTHEAST RATHER THAN NORTHEAST. THESE STORMS WILL BE THE MOST  
INTENSE, ESPECIALLY IF THEY REMAIN ISOLATED WITH LITTLE STORM  
INTERFERENCES. THE AREA BEST SUITED FOR THESE STORMS TO IMPACT SEEMS  
TO BE FROM NORTH-CENTRAL KS INTO THE FLINT HILLS. ONCE STORMS REACH  
FAR EASTERN KANSAS, OUTFLOW BOUNDARIES AND STORMS INTERACTIONS SEEM  
TO INCREASE AND CONGEAL MOST REMAINING CONVECTION INTO A LINE OF  
EMBEDDED SUPERCELLS. THIS WOULD TRANSITION THE TREAT TO ISOLATED,  
EMBEDDED TORNADOES WITHIN THE LINE, STRAIGHT LINE WINDS AND LARGE  
HAIL.  
 
SEVERE STORMS SHOULD EXIT WITH THE FRONT BY TUESDAY MORNING,  
RETURNING DRY AND WELL BELOW NORMAL TEMPERATURES TO THE REGION  
TUESDAY AFTERNOON. A MUCH COOLER AIR MASS MOVES IN FOR THE REMAINDER  
OF THE WEEK WITH RAIN AND STORM CHANCES BY THURSDAY AND FRIDAY WITH  
SOME LONG WAVE TROUGHS ENTERING THE CENTRAL US.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z MONDAY/
 
 
ISSUED AT 1228 PM CDT SUN MAY 17 2026  
 
GUSTY CONDITIONS CONTINUE THIS AFTERNOON AND INTO THE EARLY EVENING  
BEFORE GUSTS FALL BELOW 30 KNOTS BY 8-10 PM. ADDED MENTION OF  
THUNDERSTORMS AS A PROB30 GROUP AS SOME UNCERTAINTY STILL REMAINS  
WITH OVERALL COVERAGE AND EVOLUTION OF THUNDERSTORMS THIS EVENING. AN  
MVFR STRATUS DECK WILL LIKELY ACCOMPANY THE DECAYING STORMS BY THE  
EARLY MORNING AS WELL. RAIN AND STORMS MOVE EAST OF THE TERMINALS  
AFTER 4-7 AM WITH SOUTHERLY WINDS AGAIN BECOMING GUSTY BY THE MID TO  
LATE MORNING ON MONDAY.  
 

 
   
CLIMATE
 
 
ISSUED AT 336 AM CDT SUN MAY 17 2026  
 
RECORD HIGH TEMPERATURE  
 
SUNDAY MAY 17  
RECORD (YEAR) FORECAST  
TOPEKA 92 (1907) 90  
CONCORDIA 96 (1996) 97  
 
MONDAY MAY 18  
RECORD (YEAR) FORECAST  
TOPEKA 94 (1975) 91  
CONCORDIA 94 (1967, 1988) 89  
 
RECORD WARM LOW TEMPERATURE  
 
SUNDAY MAY 17  
RECORD (YEAR) FORECAST  
TOPEKA 73 (1996) 69  
CONCORDIA 68 (1902, 1906) 67  
 
MONDAY MAY 18  
RECORD (YEAR) FORECAST  
TOPEKA 71 (1911) 70  
CONCORDIA 72 (1911) 64  
 

 
   
TOP WATCHES/WARNINGS/ADVISORIES
 
 
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ008-KSZ009-KSZ010-  
KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ034-KSZ035-  
KSZ036-KSZ037-KSZ038-KSZ039-KSZ054-KSZ055-KSZ058.  
FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH TUESDAY MORNING FOR  
KSZ008-KSZ009-KSZ010-KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-  
KSZ024-KSZ034.  
WIND ADVISORY FROM 9 AM TO 9 PM CDT MONDAY FOR KSZ035-KSZ036-KSZ037-  
KSZ038-KSZ054.  
 

 
 

 
 
DISCUSSION...GRIESEMER/PRIETO  
AVIATION...GRIESEMER  
CLIMATE...GRIESEMER  
 
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