Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 240859
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
359 AM CDT FRI JUL 24 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT FRI JUL 24 2015

SMALL COMPLEX OF STORMS HAS MAINTAINED STRENGTH ACROSS NORTH CENTRAL
KS AS IT CONTINUES TO MOVE SOUTHEASTWARD. A FEW OF THESE STORMS HAVE
PRODUCED WIND GUSTS UP TO 55 MPH ASSOCIATED WITH THE REAR INFLOW
JET. THE HIGH RES MODELS HAVE STRUGGLED WITH THIS CONVECTION
THEREFORE HAVE GONE WITH LATEST OBSERVATIONAL TRENDS AND KEPT
HIGHEST POPS ACROSS THE FAR SOUTHWEST PORTION OF THE FORECAST AREA.
THESE STORMS SHOULD WEAKEN DURING THE EARLY MORNING HOURS AS THE LOW
LEVEL JET BEGINS TO DECREASE ALTHOUGH CAN NOT RULE GUSTY WINDS. A
FEW OF THE MODELS ARE HINTING AT ISENTROPIC LIFT THAT WILL MOVE OVER
EASTERN KS THIS MORNING ALTHOUGH THE MOISTURE CONTENT SEEMS
BORDERLINE. LATEST RADAR IS SHOWING SOME OF THE SHOWERS AND STORMS
FORMING NEAR THE NE/KS STATE LINE. HAVE LEFT A SLIGHT POP IN THE
REMAINDER OF THE FORECAST AREA THIS MORNING TO ACCOUNT FOR THIS LIFT
MOVING EASTWARD.

NOT MANY CHANGES TODAY WITH TEMPERATURES EXPECTED TO MIX DOWN FROM
THE ELEVATED WARM LAYER IN PLACE. HIGH TEMPERATURES SHOULD RANGE
FROM THE MID 90S IN EASTERN KS TO THE LOWER 100S IN CENTRAL KS. DEW
POINTS ARE FORECAST TO RISE INTO THE MID TO UPPER 70S WITH THE
EXCEPTION OF CENTRAL KS WHERE DEEPER MIXING SHOULD ACCOUNT FOR LOW
70 DEW POINTS AND POSSIBLY THE UPPER 60S. THE HIGH RES MODELS
CONTINUE TO SHOW DEW POINTS AS LOW AS THE UPPER 50S IN CENTRAL KS
BUT IT MAY BE UNDERESTIMATING THE SOIL MOISTURE. HEAT INDICES ARE
FORECAST TO RANGE FROM 107 TO 115 WITH THE HOTTEST CONDITIONS ACROSS
FAR EASTERN AND NORTHEAST KS LATER THIS AFTERNOON. GIVEN HEAT
INDICES COULD BE ABOVE 110 HAVE UPDATED SOME AREAS TO AN EXCESSIVE
HEAT WARNING AND KEPT THE ADVISORY GOING ELSEWHERE.

LATER THIS EVENING AND TONIGHT THE FRONT APPROACHES THE AREA FROM
THE NORTHWEST. DIURNAL CONVECTION LOOKS TO FORM ALONG THE FRONT
DURING PEAK HEATING AND WILL MOVE EASTWARD WITH TIME. IT IS
UNCERTAIN IF THIS COMPLEX WILL STAY IN NE OR REACH PORTIONS OF
NORTHERN KS. GIVEN THE WARM AND MOIST CONDITIONS TODAY INSTABILITY
WILL BE QUITE HIGH AND COULD SUPPORT SEVERE CONVECTIVE. THE DEEP
LAYER SHEAR APPEARS TO BE MARGINAL AROUND 20-30 KTS. DAMAGING WINDS
WOULD BE THE MAIN THREAT SINCE LOW LEVEL LAPSE RATES WILL BE RATHER
STEEP. HAIL WILL BE LESS OF A THREAT WITH TEMPERATURES IN THE LOWER
100S, WHILE THERE IS A VERY LOW RISK FOR A WEAK TORNADO. LOCALIZED
HEAVY RAINFALL WILL ALSO BE POSSIBLE WITH PWATS AROUND 1.25 TO 1.5
INCHES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 358 AM CDT FRI JUL 24 2015

SATURDAY MORNING...AN UPPER LEVEL TROUGH WILL ROUND AN UPPER RIDGE
AXIS CENTERED ACROSS THE SOUTHERN PLAINS. THERE COULD BE A COMPLEX
OF THUNDERSTORMS ONGOING THROUGH THE EARLY MORNING HOURS ACROSS THE
NORTHERN COUNTIES THE CWA. THE BETTER ASCENT AHEAD OF THE H5 TROUGH
WILL BE ACROSS NE AND THE NORTHERN COUNTIES OF THE CWA.

SATURDAY AFTERNOON THROUGH TUESDAY...A BROAD UPPER LEVEL RIDGE WILL
REMAIN STATIONARY ACROSS THE SOUTHERN PLAINS. MINOR UPPER LEVEL
TROUGHS WILL ROUND THE RIDGE AXIS ACROSS THE HIGH PLAINS AND INTO
THE CENTRAL PLAINS THROUGH THE PERIOD. OVERALL...THE BETTER SURFACE
CONVERGENCE WILL OCCUR ACROSS WESTERN KS/NE...EAST OF A THERMAL/LEE
SURFACE TROUGH. AFTERNOON THUNDERSTORMS WILL DEVELOP ACROSS WESTERN
KS/NE AND MOVE EAST...PERHAPS EAST-SOUTHEAST ACROSS THE NORTHERN
NORTHERN HALF OF THE CWA DURING THE NIGHT. THE ECMWF AND GFS BOTH
SHOW ANOTHER  H5 TROUGH ROUNDING THE UPPER RIDGE LATE SATURDAY
AFTERNOON INTO SATURDAY NIGHT...PROVIDING A CHANCE FOR THUNDERSTORMS
ACROSS THE CWA SATURDAY NIGHT INTO SUNDAY MORNING. OTHERWISE EXPECT
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS. THE PRIMARY HAZARD WITH
THE STRONGER THUNDERSTORMS WILL BE ISOLATED STRONG TO SEVERE WIND
GUSTS AND BRIEF HEAVY RAINFALL.

AS LONG AS NO MAJOR OUTFLOW BOUNDARIES DEVELOP OR DEBRIS CLOUDS FROM
MORNING CONVECTION LINGER INTO THE AFTERNOON...AFTERNOON HIGH
SATURDAY THROUGH TUESDAY WILL WARM INTO THE LOWER TO UPPER
90S...WITH SOME 100 DEGREE READINGS POSSIBLE ACROSS THE SOUTHWEST
COUNTIES. THE MIXING MAY NOT BE AS DEEP IN THE EASTERN COUNTIES
DURING THE AFTERNOON HOURS ALLOWING FOR SURFACE DEWPOINTS TO REMAIN
IN THE MID TO UPPER 70S. EXPECT AFTERNOON HEAT INDICES TO BE AROUND
105 DEGREES EACH AFTERNOON. THE WESTERN COUNTIES MAY MIX A BIT
DEEPER DURING THE AFTERNOON RESULTING IN SLIGHTLY LOWER AFTERNOON
HEAT INDICES OF 100-104 DEGREES.

WEDNESDAY THROUGH FRIDAY...AN AMPLIFIED H5 TROUGH WILL MOVE ACROSS
THE NORTHERN PLAINS TUESDAY NIGHT INTO WEDNESDAY. LOW-LEVEL CAA
ACROSS THE NORTHERN PLAINS WILL PUSH A COLD FRONT SOUTHWARD ACROSS
THE CWA ON WEDNESDAY AFTERNOON AND EVENING. SURFACE CONVERGENCE
ALONG THE FRONT ALONG WITH ASCENT AHEAD OF THE THE H5 TROUGH MAY
CAUSE SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP. THE FRONT WILL
PUSH SOUTH OF THE CWA WEDNESDAY NIGHT AS A SURFACE RIDGE OF HIGH
PRESSURE BUILDS SOUTHWARD ACROSS THE CENTRAL PLAINS. HIGHS WEDNESDAY
AND THURSDAY WILL COOL INTO THE MID TO UPPER 80S BEHIND THE SURFACE
FRONT. SKIES WILL BECOME MOSTLY SUNNY ON THURSDAY. THE SURFACE RIDGE
WILL SHIFT EAST OF THE AREA ON FRIDAY AND SOUTHERLY WINDS WILL WARM
HIGHS BACK INTO THE UPPER 80S TO LOWER 90S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1224 AM CDT FRI JUL 24 2015

EXPECT VFR CONDITIONS FOR MUCH OF THE PERIOD. IT DOES NOT APPEAR
THAT THE CONVECTION WILL REACH MHK BEFORE WEAKENING. 00Z NAM
SOUNDINGS SUGGEST A POSSIBLE MVFR CIG AND OR VIS DEVELOPING
AROUND 09Z ALTHOUGH THE BOUNDARY MAY REMAIN MIXED ENOUGH TO STAY
VFR. CLOUDS FROM ONGOING CONVECTION IN NORTH CENTRAL KS MAY
PREVENT MHK FROM THE POSSIBLE HAZE.


&&

.TOP WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING FROM NOON TODAY TO 9 PM CDT THIS EVENING
FOR KSZ011-012-023-024-026-038>040-055-056-059.

HEAT ADVISORY FROM NOON TODAY TO 9 PM CDT THIS EVENING FOR
KSZ008>010-020>022-034>037-054-058.

&&

$$

SHORT TERM...SANDERS
LONG TERM...GARGAN
AVIATION...53



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