588
FXUS63 KTOP 040513
AFDTOP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
1213 AM CDT SAT APR 4 2026
KEY MESSAGES
- A BROKEN LINE OF THUNDERSTORMS IS EXPECTED TO MOVE EAST ACROSS THE
AREA THIS AFTERNOON, EXITING TO THE EAST AROUND 8PM. SOME OF THE
THUNDERSTORMS COULD BE SEVERE.
- COOL AND DRY WEATHER IS FORECAST FOR THE WEEKEND. THOSE WITH A HEAD
START ON GARDENS MAY WANT TO PROTECT TENDER VEGETATION WITH LOWS
FORECAST TO BE IN THE 30S.
- MILD WEATHER IS FORECAST FOR NEXT WEEK WITH INCREASING
PRECIPITATION CHANCES TOWARDS THE END OF NEXT WEEK.
DISCUSSION
ISSUED AT 1246 PM CDT FRI APR 3 2026
1730Z WATER VAPOR IMAGERY SHOWED A CLOSED UPPER LOW MOVING INTO NEB
AND SD. SURFACE OBS PLACED A COLD FRONT FROM NORTHEAST KS INTO SOUTH
CENTRAL KS. STRONG TEMPERATURE ADVECTION WAS NOTED ON BOTH SIDE OF
THE FRONT WITH A 30+ DEGREE GRADIENT ACROSS THE 40 MILE FRONTAL
ZONE.
MODELS ARE IN GOOD AGREEMENT WITH A BROKEN LINE OF THUNDERSTORMS
MOVING ACROSS THE FORECAST AREA WITH THE FRONT THIS AFTERNOON. MUCH
OF THIS ACTIVITY IS EXPECTED TO BE EXITING ANDERSON COUNTY BETWEEN 7
AND 8 PM. 17Z ANALYSIS SHOWS THE ENVIRONMENT IS ALREADY UNSTABLE
WITH LITTLE TO NO INHIBITION. MLCAPE VALUES ARE AROUND 2000 J/KG
WITH BULK SHEAR OF 40 TO 50KT. MAIN QUESTION IS WHETHER STORM
MERGERS WILL BE ENOUGH TO DISRUPT UPDRAFTS AND STORM INTENSITY, OR
IF UPDRAFTS WILL BE ABLE TO PERSIST UNIMPEDED. THE MOTION OF THE
FRONT IS FORECAST TO BE VERY CLOSE TO THE MOTION OF A RIGHT MOVING
SUPERCELL FROM FORECAST SOUNDINGS. SO IT LOOKS UNLIKELY STORMS WILL
DEVELOP AND MOVE OFF THE BOUNDARY INTO THE WARM SECTOR. LARGE HAIL
AND DAMAGING WINDS LOOK TO BE THE MAIN CONCERNS, BUT THERE IS A NON-
ZERO CHANCE FOR A TORNADO WITH THE EFFECTIVE SRH PROGGED TO BE NEAR
200 M2/S2. THE CAMS SEEM TO HAVE A REASONABLE HANDLE WITH THE FRONT
AND HAVE USED THAT AS A FIRST ITERATION FOR WINDS AND TEMPS INTO
THIS EVENING.
SURFACE RIDGING WITH DRY AIR IS EXPECTED TO MOVE INTO THE CENTRAL
PLAINS TONIGHT BEHIND THE FRONT. THIS SHOULD BRING AN END TO PRECIP
CHANCES AND SET UP NICE WEATHER FOR THE WEEKEND WITH PLENTY OF
SUNSHINE AND MORE SPRING LIKE TEMPS. LOWS THE NEXT SEVERAL DAYS LOOK
TO FALL INTO THE MIDDLE AND LOWER 30S. SO ANYONE WHO GOT A HEAD
START ON THEIR GARDEN MAY WANT TO TAKE ACTION TO PROTECT SENSITIVE
VEGETATION. SINCE IT IS STILL EARLY APRIL, WE DON'T HAVE ANY PLANS
TO GO WITH FROST OR FREEZE HEADLINES JUST YET.
MODELS SHOW A NORTHWEST FLOW PATTERN CHANGING TO ONE WITH ENERGY
DIGGING INTO THE SOUTHWESTERN US FOR NEXT WEEK. DIFFERING SOLUTIONS
HAVE INCREASED THE SPREAD IN POTENTIAL OUTCOMES FOR NEXT WEEK AS
SEEN IN THE 00Z ENSEMBLE DATA. FOR MONDAY AND TUESDAY, A SUBTLE
SHORTWAVE IS PROGGED TO MOVE ACROSS THE CENTRAL PLAINS ON TUESDAY
WITH A RETURN FLOW DEVELOPING AHEAD OF IT. THE GFS AND ECMWF SHOW
SOME LIGHT QPF WITHIN THE WARM AIR ADVECTION PATTERN. BUT CONFIDENCE
IS MODEST WITH THESE CHANCES AS A MAJORITY OF THE ENSEMBLES FAIL TO
DEVELOP MEASURABLE PRECIP. DEPENDING ON TEMPS THERE COULD BE SOME
LIGHT RAIN OR SNOW IF THE MOISTURE RETURN IS GOOD ENOUGH FOR PRECIP
TO DEVELOP. WITH QPF PROGS GENERALLY AROUND A TENTH OF AN INCH
IMPACTS LOOK TO BE MINOR AND MAINLY ACROSS FAR NORTHEAST KS LATE
MONDAY NIGHT OR TUESDAY MORNING. BETTER PRECIP CHANCES LOOK TO OCCUR
LATER IN THE WEEK AS A FRONTAL BOUNDARY SAGS INTO THE FORECAST AREA
THURSDAY. A SOUTHWEST FLOW ALOFT COULD BRING PERTURBATIONS OVER THE
FRONTAL BOUNDARY WITH PRECIP CHANCES TO END THE WEEK. THERE IS A
BETTER SIGNAL FROM THE ENSEMBLES FOR THIS SCENARIO AND THINK THE
LIKELY POPS FROM THE NBM ARE PLAUSIBLE. TEMPS ARE FORECAST TO REMAIN
MODERATE WITH OCCASIONAL FRONTAL BOUNDARIES LIMITING A SUSTAINED
WARM UP.
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
ISSUED AT 1213 AM CDT SAT APR 4 2026
BROKEN IFR STRATUS OBSERVED NORTH AND EAST OF TERMINALS IS
PROGGED TO ENTER SITES AROUND 08Z. NORTHWEST WINDS AT THIS TIME
INCREASE ABOVE 10 KTS, OCCASIONALLY GUSTING AROUND 20 KTS
OVERNIGHT. GUSTY WINDS PERSIST THROUGHOUT THE DAYTIME PERIOD AS
CLOUDS GRADUALLY SCATTER TO VFR.
TOP WATCHES/WARNINGS/ADVISORIES
NONE.
DISCUSSION...WOLTERS
AVIATION...22
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