742  
FXUS63 KTOP 161143  
AFDTOP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TOPEKA KS  
643 AM CDT TUE SEP 16 2025  
   
KEY MESSAGES  
 
- A FEW ISOLATED SHOWERS MAY FORM THIS AFTERNOON WITH ABOUT A 20%  
CHANCE FOR POP-UP SHOWERS OR A STORM OVER EAST-CENTRAL INTO FAR  
NORTHEASTERN AREAS.  
 
- THE FIRST OF TWO MAIN DISTURBANCES MOVE ACROSS THE AREA WEDNESDAY  
MORNING INTO MIDDAY WITH PRECIPITATION CHANCES INCREASING FROM 40-  
60%.  
 
- WEDNESDAY EVENING INTO EARLY THURSDAY MORNING THE SECOND UPPER  
LEVEL DISTURBANCE MOVES ACROSS THE AREA INCREASING PRECIPITATION  
CHANCES TO AROUND 60-70% CHANCE.  
 
- COOLER TEMPERATURES FINALLY MOVE INTO THE AREA THURSDAY INTO  
FRIDAY WITH SEASON NORMAL TEMPERATURES THROUGH THE WEEKEND INTO  
EARLY NEXT WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 328 AM CDT TUE SEP 16 2025  
 
EARLY THIS MORNING, THE UPPER AIR PATTERN ACROSS THE CONUS SHOWS AN  
UPPER LOW PRESSURE SYSTEM OVER THE MID-ATLANTIC REGION WITH ANOTHER  
POSITIONED OVER THE NORTHERN ROCKIES. A LOW PRESSURE TROUGH IS  
SITUATED THROUGH THE DAKOTAS INTO THE HIGH PLAINS REGION WITH A  
BAROCLINIC ZONE SET UP ACROSS THIS REGION WITH A WARM AND HUMID  
AIRMASS TO THE EAST OF THIS FRONTAL ZONE WITH DEWPOINTS WELL INTO  
THE 60S ACROSS THE FORECAST AREA EXTENDING NORTH INTO THE UPPER MS  
VALLEY. TO THE NORTHWEST OF THIS ZONE, A MUCH COOLER AIRMASS IS IN  
PLACE AND POISED TO GRADUALLY PUSH INTO THE FORECAST AREA MODIFYING  
AS IT DOES BUT YIELDING OVERALL COOLER TEMPERATURES BY THE END OF  
THE WEEK INTO THE THIS WEEKEND.  
 
CLOUDS CONTINUE TO DIMINISH ACROSS EASTERN AREAS EARLY THIS MORNING.  
WITH MOSTLY CALM WINDS IN PLACE THERE MAY BE ENOUGH TIME FOR  
RADIATIONAL COOLING TO ALLOW FOR SOME LOW LYING AREAS TO SEE SHALLOW  
PATCH FOG TO DEVELOP THROUGH SUNRISE. IMPACTS WOULD LIKELY BE  
MINIMAL.  
 
INTO THIS AFTERNOON A FEW ISOLATED SHOWERS OR A STORM OR TWO MAY  
FORM WITHIN AN UNSTABLE AIRMASS GENERALLY DURING PEAK HEATING HOURS.  
THE BEST CHANCES REMAIN GENERALLY FROM EAST-CENTRAL KS THROUGH FAR  
NORTHEASTERN KS AREAS. NO SEVERE WEATHER IS EXPECTED BUT DO EXPECT  
THE STRONGEST UPDRAFTS COULD PRODUCE STRONG WIND AS THEY COLLAPSE  
WITH LITTLE SHEAR IN PLACE STORMS LIKELY ONLY LAST ABOUT 20-30  
MINUTES IF THEY DO FORM. TEMPERATURES THIS AFTERNOON WILL STILL BE  
AROUND 90 WITH NO SIGNIFICANT AIRMASS CHANGE.  
 
INTO WEDNESDAY MORNING AND MIDDAY, THE NORTHERN ROCKIES UPPER LOW  
BEGINS TO DIG FURTHER SOUTH AND A LEAD SHORTWAVE EMERGES OUT OF THE  
CENTRAL ROCKIES AND MOVES MAINLY ACROSS NORTHERN AREAS. ABOUT A 40-  
60% CHANCE OF PRECIPITATION SETS UP ACROSS THE AREA. FORECAST  
SOUNDING PROFILES SUGGEST THAT ANY STORMS THAT DEVELOP WOULD BE HIGH  
BASED WITH SUB-CLOUD DRY AIR IN PLACE SIMILAR TO AN INVERTED-V TYPE  
PROFILE. WHILE SHEAR AND MID-LEVEL LAPSE RATES REMAIN UNFAVORABLE  
FOR SEVERE WEATHER, WIND COULD AGAIN BE STRONG WITH A FEW STORMS AS  
UPDRAFTS COLLAPSE. A FEW SHOWERS MAY BRING BRIEF HEAVY RAIN BUT  
LIKELY REMAIN LOCALIZED AS SATURATION IN FORECAST SOUNDS APPEARS TO  
BE OVERALL SHALLOW.  
 
A SECOND SHORTWAVE WORKS THROUGH WEDNESDAY EVENING INTO THURSDAY  
MORNING POSSIBLY LASTING INTO THE AFTERNOON AS THE LARGER TROUGH  
BECOMES NEGATIVELY TILTED AND SLOWLY LIFTS THROUGH THE AREA. THIS  
SHOULD PROVIDE ADDITIONAL FORCING ACROSS THE REGION HELPING TO  
INCREASE PRECIPITATION CHANCES TO 60-70%. SEVERE WEATHER LOOKS  
UNLIKELY AGAIN WITH LIMITED INSTABILITY MOSTLY IN THE FORM OF TALL  
SKINNY CAPE PROFILES IN PLACE WITH WEAK SHEAR AGAIN IN PLACE.  
 
THE COOLER MODIFIED AIRMASS PUSHES INTO THE AREA COMPLETELY ON  
FRIDAY INTO THE WEEKEND WITH THE SURFACE RIDGE EXPANDING SOUTH. LOOK  
FOR HIGH TEMPERATURES TO BE IN THE UPPER 70S TO AROUND 80 DEGREES  
WITH LOWER OVERALL PRECIPITATION CHANCES AROUND 20-30% ANY GIVEN  
PERIOD.  
 
 
   
AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/  
 
ISSUED AT 634 AM CDT TUE SEP 16 2025  
 
STILL MOSTLY VFR CONDITIONS EXPECTED THROUGH THIS PERIOD WITH  
CHANGES NEAR THE VERY END OR JUST AFTER THE PERIOD GENERALLY  
FROM WEST TO EAST. WINDS WILL REMAIN GENERALLY AROUND OR UNDER  
10KTS FROM THE SSE. THERE COULD BE A FEW ISOLATED SHOWERS EARLY  
THIS MORNING BUT CONFIDENCE IN FORMATION IS STILL TOO LOW TO  
INCLUDE. BEST CHANCES FOR SHOWERS AND STORMS STILL COME BY THE  
END OF THE NEXT PERIOD AS FRONTAL SYSTEM APPROACHES THE AREA  
FROM THE WEST. CHANCES FOR SHOWERS AND STORMS THIS AFTERNOON MAY  
IMPACT EASTERN TERMINALS BUT CONFIDENCE IN FORMATION IS AGAIN  
TOO LOW TO INCLUDE.  
 
 
   
TOP WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION...DRAKE  
AVIATION...DRAKE  
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