343
FXUS64 KLZK 130512 AAC
AFDLZK
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
1212 AM CDT TUE AUG 13 2013
.DISCUSSION...
UPDATED TO INCLUDE THE 06Z AVIATION DISCUSSION BELOW...
&&
.AVIATION...
SHRA/TSRA WILL CONTINUE TO BE POSSIBLE THROUGH MUCH OF THE TAF
PERIOD. BEST CHANCES FOR PRECIP HOWEVER...WILL BE ACROSS THE SRN
HALF OF THE STATE...WITH DOMINANT SHRA/TSRA EXPECTED AT CENTRAL
AND SRN TERMINALS. PATCHY FOG AND SOME LOW CIGS WILL BE POSSIBLE
IN AREAS THAT ALREADY SAW RAINFALL THROUGH THIS TUE MORNING. MVFR
OR LOWER CONDITIONS CAN BE EXPECTED UNDER ANY PRECIP ACTIVITY AS
WELL. IMPROVING CONDITIONS WILL BE SEEN ACROSS THE NRN SITES BY TUE
AFTERNOON AND ESPECIALLY TUE NIGHT.
&&
.PREV DISCUSSION... /ISSUED 840 PM CDT MON AUG 12 2013/
DISCUSSION...
SHORT TERM CONCERNS ARE HOW MUCH CONVECTION WILL DEVELOP AFTER
MIDNIGHT WITH NEXT SHORT WAVE AND MCV DEVELOPMENT. CURRENTLY SEE ON
GOING CONVECTION OVER WESTERN OK MOVING IN THE MEAN UPPER W TO NW
FLOW. AS THE SURFACE BOUNDARY BECOMES MORE ORIENTED NW TO E OVER
AR...THIS FEATURE IS EXPECTED TO MOVE ALONG THE BOUNDARY AND DEVELOP
SHOWERS AND THUNDERSTORMS. TIMING AT THIS TIME MAY BE CLOSER TO 12Z
TUESDAY INTO WESTERN AR...WHILE FAR NW AR MAY SEE CONVECTION A BIT
EARLIER. WILL ADJUST POPS OVERNIGHT TO HIGHEST IN THE NW AND
LOWEST IN THE SE. FLASH FLOOD WATCH WILL BE IN EFFECT THROUGH
TUESDAY WITH EXPECTED RAIN FALL. MODELS ARE HINTING THE MAIN SURGE
OF CONVECTION WILL GRADUALLY MOVE SOUTH TUESDAY WITH CENTRAL AREAS
RECEIVING THE MOST...THEN SOUTHERN AREAS LATER TUESDAY INTO
WEDNESDAY BEFORE THE FRONT PUSHES SOUTH OF AR. OTHERWISE WILL FINE
TUNE OVERNIGHT POPS...QPF AND TEMPS WITH LATE EVENING UPDATE. (59)
PREV DISCUSSION... /ISSUED 217 PM CDT MON AUG 12 2013/
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...
AN UPPER LEVEL RIDGE WILL BEGIN TO BUILD ACROSS THE WESTERN US
DURING THE SHORT TERM AS A TROF DEVELOPS ACROSS THE EAST. ARKANSAS
WILL TRANSITION TO A NWLY FLOW ALOFT...AND AT THE SURFACE A HIGH
PRESSURE SYSTEM WILL BUILD INTO THE GREAT LAKES REGION...PUSHING A
SURFACE COLD FRONT SOUTHWARD INTO THE STATE. THE FRONT SHOULD MOVE
SLOWLY SOUTHWARD ACROSS THE AREA TOMORROW AND MAY STALL FOR A
TIME...BEFORE FINALLY PUSHING SOUTH OF THE AREA ON WEDNESDAY.
THE SLOW MOVING BOUNDARY WILL BE A FOCAL POINT FOR SHOWERS AND
THUNDERSTORMS...AND HEAVY RAIN COULD OCCUR IN AREAS WHERE TRAINING
ECHOES OCCUR...ESPECIALLY IF THE FRONT STALLS OUT FOR A TIME. AT
PRESENT A FLASH FLOOD WATCH HAS BEEN POSTED BEGINNING LATER TONIGHT
FOR MAINLY THE NORTHERN HALF OF THE STATE.
EARLIER MODEL RUNS WERE TENDING TO FOCUS THE HEAVIEST PRECIPITATION
ACROSS THE NORTHERN HALF OF THE STATE FROM THIS EVENT...ALTHOUGH
SUBSEQUENT MODEL RUNS ARE NOW INDICATING MORE OF A NW-SE AXIS ACROSS
THE CWA. ITS GOING TO BE DIFFICULT TO ACCURATELY PREDICT WHERE THE
HEAVIEST RAINFALL WILL OCCUR AS IT WILL DEPEND UPON A NUMBER OF
FACTORS...NAMELY THE SPEED OF THE FRONT...AND WHERE IT MAY SLOW OR
STALL..AND THE TIMING OF ANY UPPER LEVEL DISTURBANCES MOVING ACROSS
THE AREA.
ALL OF THE PRECIP SHOULD BE CLEAR OF THE NORTHERN HALF OF THE STATE
BY THURSDAY MORNING...AND BY THURSDAY AFTERNOON AND NIGHT ACROSS THE
SOUTHERN HALF OF THE AREA. MUCH COOLER AND DRIER AIR WILL BE
FILTERING INTO THE REGION BEHIND THE FRONT...BRINGING UNUSUALLY MILD
TEMPERATURES TO ARKANSAS FOR THE MIDDLE OF AUGUST. &&
LONG TERM...FRIDAY THROUGH MONDAY...
DRY CONDITIONS...WITH A WARMING TREND ARE EXPECTED DURING THIS
PERIOD. ABNORMALLY COOL CONDITIONS WILL START THE PERIOD...AS
FORECAST MAX TEMPERATURES AVERAGE 8-12 DEGREES BELOW NORMAL. NEAR
NORMAL TEMPERATURES SHOULD DEVELOP LATE IN THE PERIOD. &&
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 64 81 62 81 / 40 30 10 10
CAMDEN AR 72 82 65 87 / 60 60 30 20
HARRISON AR 63 80 59 79 / 40 30 10 10
HOT SPRINGS AR 70 85 63 84 / 60 40 20 10
LITTLE ROCK AR 68 85 62 83 / 50 40 20 10
MONTICELLO AR 71 84 64 87 / 60 60 30 20
MOUNT IDA AR 68 83 63 85 / 60 50 20 10
MOUNTAIN HOME AR 64 81 59 82 / 40 20 10 10
NEWPORT AR 64 81 64 82 / 40 30 10 10
PINE BLUFF AR 70 85 64 82 / 50 50 20 10
RUSSELLVILLE AR 67 87 62 85 / 50 30 20 10
SEARCY AR 66 81 63 82 / 50 30 20 10
STUTTGART AR 69 82 64 82 / 50 40 20 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR BAXTER-BOONE-CLEBURNE-
CONWAY-FAULKNER-FULTON-GARLAND-INDEPENDENCE-IZARD-JACKSON-
JOHNSON-LOGAN-LONOKE-MARION-MONROE-MONTGOMERY-NEWTON-PERRY-POLK-
POPE-PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN BUREN-
WHITE-WOODRUFF-YELL.
&&
$$
AVIATION...62