000
FXUS64 KOHX 210154 AAA
AFDOHX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NASHVILLE TN
854 PM CDT MON MAY 20 2013

.UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO REFLECT CLEAR SKIES
ACROSS THE MID STATE THRU THE EVENING HRS...WITH A GENERAL INCREASE
OF CLOUDINESS WEST TO EAST ACROSS THE MID STATE AFTER MIDNIGHT. HAVE
ALSO MENTIONED PATCHY FOG AFTER MIDNIGHT PLATEAU PER CONTINUED LOW
LEVEL MOISTURE POOLING POTENTIAL. WITH SOME UNCERTAINTIES CONCERNING
ACTUAL CLOUD COVERAGE LATE...WILL CONTINUE TO GO CLOSE TO CURRENT
FORECAST REASONING ON OVERNIGHT LOWS.
&&

.PREV DISCUSSION.../ISSUED 603 PM CDT MON MAY 20 2013/

UPDATE...FOR AVIATION.

AVIATION...
00Z TAFS...UPPER LEVEL RIDGE WILL CONTINUE TO BE THE MAIN
INFLUENCE WITH FAIR WX THROUGH THIS EVENING. SOME MVFR BR OR
PERHAPS PATCHY STRATUS IS POSSIBLE TOWARD DAYBREAK. S WINDS WILL
BECOME SOMEWHAT GUSTY ON TUESDAY...TO 20KT AT TIMES...ESPECIALLY
FOR CKV. THE RIDGE WILL BEGIN TO MOVE EAST WITH AN APPROACHING
DISTURBANCE BRINGING A CHANCE FOR TSRA BY THE END OF THE PERIOD.
COVERAGE WILL BE GENERALLY ISOLD...BUT COVERAGE WILL BE INCREASING
FROM THE WEST...SO INCLUDING A VCTS FOR CKV AFTER 21Z.

13

PREV DISCUSSION... /ISSUED 324 PM CDT MON MAY 20 2013/

AFTERNOON CU DEVELOPMENT IS WIDESPREAD ACROSS THE MID STATE THIS
AFTERNOON AS DEWPOINTS HAVE CONTINUED TO RISE. MID LEVEL CAP IS
RATHER STRONG ACCORDING TO THE 12Z SOUNDING FROM THIS MORNING. THE
HIGHER DEWPOINTS HAVE ACTED TO LOWER CONVECTIVE TEMPS BUT CURRENT
TEMPS ARE STRUGGLING TO RISE GIVEN THE EXTRA CLOUD COVER.

FOR TONIGHT`S FORECAST...WILL INCLUDE A 20 POP BUT ONLY FOR THE
NW. THIS IS IN LINE WITH THE HRRR REFLECTIVITY FCST WHICH SHOWS
LITTLE IF ANY DEVELOPMENT. OVERALL...IT JUST APPEARS THAT THERE IS
TOO MUCH VERTICAL DRYNESS IN PLACE.

A SLIGHT CHANCE OF SHOWERS AND TSTMS WILL BE IN THE FCST AGAIN FOR
TUESDAY. MOISTURE LEVELS SHOULD BE HIGHER AND WE DO SEE MORE 18Z CAP
EROSION WITH THE GFS MODEL. THE INCREASE IN MOISTURE WILL BE AIDED
BY AN APPROACHING FRONTAL BOUNDARY WHICH WILL IMPACT THE AREA LATE
TUESDAY NIGHT AND INTO WEDNESDAY. AT THAT TIME...A SLIGHT RISK OF
SEVERE WEATHER IS IN THE FCST FOR OUR NW COUNTIES. BEST OMEGA
FORCING APPEARS TO BE AROUND 06Z WEDNESDAY ACROSS WESTERN TN.
BUT...THERE COULD BE A FEW STRONGER CELLS OVER THAT SAME AREA
EARLIER ON TUES AFTERNOON. STORM MOTION SHOULD RUN FROM SW TO NE.

SHOWERS AND TSTMS TO PERSIST INTO WEDNESDAY. ITS IMPORTANT TO NOTE
HOWEVER THAT OVERALL POPS WITH THIS SYSTEM ARE NOT DRASTICALLY HIGH.
IN FACT...MODELS NOT LEANING TOWARD DEEP MOISTURE WITH A WIDESPREAD
AREA OF RAIN OCCURRING. NEVERTHELESS...POPS IN THE 40-60 PERCENT
RANGE WILL BE INCLUDED FOR TUESDAY NT INTO WEDNESDAY. AFTER A FEW
LINGERING SHOWERS ON THURSDAY ACROSS THE PLATEAU...CLEARING WILL
OCCUR WITH DRIER AIR MOVING IN.

FOR THE NEAR TERM TEMPS...WILL AGAIN UNDERCUT THE HIGH TEMPS FOR
TUESDAY AND WEDNESDAY. OVERNIGHT LOWS FROM THE GUIDANCE APPEARS
REASONABLE.

IN THE EXT FCST...NICE LATE MAY CONDITIONS ARE ON TAP FOLLOWING THE
FROPA WHICH WAS MENTIONED IN THE SHORT TERM TIME FRAME.
THUS...SUNSHINE TO RETURN IN EARNEST FOR FRIDAY AND INTO THE
WEEKEND. THERMAL TROUGHING WILL BE SLOW TO GIVE WAY AND
THUS...MOSTLY SUNNY SKIES WITH BELOW NORMAL TEMPS AND LOWER
HUMIDITY LEVELS WILL PREVAIL THU THROUGH SAT. SUNDAY AND MONDAY...UPPER
RIDGING AND HEIGHT RISES WILL BE ON TAP. THIS WILL EQUATE TO HIGH
TEMPS BACK UP INTO THE 80S. BUT...STILL NOT SEEING ANY APPRECIABLE
PRECIP CHANCES THROUGH MONDAY.

21

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$
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