Area Forecast Discussion


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