FXUS64 KOHX 302349 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 649 PM CDT MON AUG 30 2010 .UPDATE...FOR 31/00Z AVIATION FORECAST && .AVIATION... TONGUE OF MOISTURE CONTINUES TO STREAM NORTH ALONG INTERSTATE 65 THROUGH ALABAMA AND INTO MIDDLE TN. THIS IN AN AREA OF POSITIVE VORTICITY ADVECTION. PATCHY LIGHT RAIN SHOWING UP ON DOPPLER ALIGNED NORTH TO SOUTH ALONG I65 HAS BEEN DIMINISHING LAST FEW VCPS WITH A WESTWARD COMPONENT BECOMING MORE EVIDENT IN MID STATE. CRAS CONTINUES TO WORK MOISTURE NORTHWARD TONIGHT INTO TUESDAY BUT APPEARS TO BE WEAKENING IT WITH TIME. EXPECT MOSTLY MID-LEVEL CLOUDINESS TONIGHT INTO TUESDAY WITH SPRINKLES FROM TIME TO TIME. EXPECT TO SEE MVFR AGAIN AT CSV LATE NIGHT/SUNRISE TUESDAY DUE TO FOG. BOYD && .PREV DISCUSSION... /ISSUED 317 PM CDT MON AUG 30 2010/ DISCUSSION...WATER VAPOR CHANNEL REVEALS THE WEAK UPPER TROUGH AXIS FROM STL TO MOB. PROGS INDICATE THAT THIS TROUGH WILL GO AWAY AND ANY SUPPORT FOR CONVECTION WILL GO WITH IT. CLOUD COVER SHOULD ALSO SLOWLY DIMINISH FROM THE EAST AS THE SFC RIDGE EXERTS IT INFLUENCE. SFC RIDGE MOVES EWD OVER THE MIDSTATE AS "EARL" BRUSHES THE EAST COAST ON THU. LITTLE IF ANY CONVECTION EXPECTED THROUGH THU EVE. ANY CLOUDINESS ASSOCIATED WITH "EARL" SHOULD REMAIN WELL TO THE EAST. ON WED A STRONG H5 TROUGH WILL DROP SEWD INTO THE NRN PLAINS AND THEN ROLL THROUGH THE GREAT LAKES ON THU NGT AND FRI. THIS BRINGS A FRONTAL SYSTEM SEWD FROM THE MIDWEST INTO THE MIDSTATE ON FRI. THIS FRONT WILL BRING A CHANCE OF CONVECTION AND A GOOD BIT OF DRIER AND COOLER AIR BEHIND THE FRONT. HIGH IN THE LOWER 80S ARE EXPECTED FOR THE NORTH HALF OF THE AREA ON SAT. THE SFC RIDGE PUSHES THE FRONT TO THE GULF COAST BY SUN WITH A DRY AND COOL SFC RIDGE SITTING OVER THE OH/TN VALLEYS THIS WEEKEND. SLY FLOW RETURNS ON MON AFTN BUT ANY CHANCE OF RAIN WILL PROBABLY WAIT UNTIL MID WEEK. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 310420 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 1120 PM CDT MON AUG 30 2010 .UPDATE...FOR 31/06Z AVIATION FORECAST && .AVIATION... MOISTURE THROUGH THE MID AND UPPER LEVELS STILL STREAMING NORTH FROM GULF REGION WITH NEAREST PRECIP IN NORTH ALABAMA. AREA OF SHOWERS IN NORTH ALABAMA SEEMS TO BE ERODING ON NORTH SIDE AS IT TRIES TO WORK TOWARD SOUTHERN MIDDLE TN. CRAS KEEPS MID AND UPPER LEVEL MOIST TONGUE ACROSS MIDDLE TN THROUGH TUESDAY. BASICALLY LOOKING AT VFR THROUGH THE PERIOD AT BOTH SITES BUT EXPECT MVFR AT CSV OVERNIGHT INTO SUNRISE DUE TO FOG AND HZ. BOYD && .PREV DISCUSSION... /ISSUED 649 PM CDT MON AUG 30 2010/ UPDATE...FOR 31/00Z AVIATION FORECAST AVIATION... TONGUE OF MOISTURE CONTINUES TO STREAM NORTH ALONG INTERSTATE 65 THROUGH ALABAMA AND INTO MIDDLE TN. THIS IN AN AREA OF POSITIVE VORTICITY ADVECTION. PATCHY LIGHT RAIN SHOWING UP ON DOPPLER ALIGNED NORTH TO SOUTH ALONG I65 HAS BEEN DIMINISHING LAST FEW VCPS WITH A WESTWARD COMPONENT BECOMING MORE EVIDENT IN MID STATE. CRAS CONTINUES TO WORK MOISTURE NORTHWARD TONIGHT INTO TUESDAY BUT APPEARS TO BE WEAKENING IT WITH TIME. EXPECT MOSTLY MID-LEVEL CLOUDINESS TONIGHT INTO TUESDAY WITH SPRINKLES FROM TIME TO TIME. EXPECT TO SEE MVFR AGAIN AT CSV LATE NIGHT/SUNRISE TUESDAY DUE TO FOG. BOYD PREV DISCUSSION... /ISSUED 317 PM CDT MON AUG 30 2010/ DISCUSSION...WATER VAPOR CHANNEL REVEALS THE WEAK UPPER TROUGH AXIS FROM STL TO MOB. PROGS INDICATE THAT THIS TROUGH WILL GO AWAY AND ANY SUPPORT FOR CONVECTION WILL GO WITH IT. CLOUD COVER SHOULD ALSO SLOWLY DIMINISH FROM THE EAST AS THE SFC RIDGE EXERTS IT INFLUENCE. SFC RIDGE MOVES EWD OVER THE MIDSTATE AS "EARL" BRUSHES THE EAST COAST ON THU. LITTLE IF ANY CONVECTION EXPECTED THROUGH THU EVE. ANY CLOUDINESS ASSOCIATED WITH "EARL" SHOULD REMAIN WELL TO THE EAST. ON WED A STRONG H5 TROUGH WILL DROP SEWD INTO THE NRN PLAINS AND THEN ROLL THROUGH THE GREAT LAKES ON THU NGT AND FRI. THIS BRINGS A FRONTAL SYSTEM SEWD FROM THE MIDWEST INTO THE MIDSTATE ON FRI. THIS FRONT WILL BRING A CHANCE OF CONVECTION AND A GOOD BIT OF DRIER AND COOLER AIR BEHIND THE FRONT. HIGH IN THE LOWER 80S ARE EXPECTED FOR THE NORTH HALF OF THE AREA ON SAT. THE SFC RIDGE PUSHES THE FRONT TO THE GULF COAST BY SUN WITH A DRY AND COOL SFC RIDGE SITTING OVER THE OH/TN VALLEYS THIS WEEKEND. SLY FLOW RETURNS ON MON AFTN BUT ANY CHANCE OF RAIN WILL PROBABLY WAIT UNTIL MID WEEK. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 082357 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 657 PM CDT WED SEP 8 2010 .UPDATE...FOR 09/00Z AVIATION FORECAST && .AVIATION... HAND ANALYZED SURFACE COOL FRONT RIGHT ON OUR DOORSTEPS HERE AT OHX AT 08/23Z. BASE VELOCITY SHOWING VERY LIGHT NORTHWEST WIND WITH DRIER AIR FILTERING IN FROM THE NORTHWEST PER 64 DEWPOINT AT BNA AT 23Z WHILE BWG HAD A 53 AND PAH A 56. KY MESONET SHOWING DEWPOINTS IN THE MID 40S WEST OF I65. CANADIAN HIGH PRESSURE BUILDS DOWN INTO MID STATE TONIGHT AND CONTINUES TO DO SO ON THURSDAY. MID LEVEL MOISTURE STREAMING EAST FROM REMNANTS OF HERMINE IN CENTRAL PLAINS IS WORKING INTO DRIER AIRMASS. EXPECT MID LEVEL CLOUDINESS TO HANG AROUND OVERNIGHT BECOMING SCATTERED BY MID MORNING THURSDAY AT BOTH SITES AS AIR MASS CONTINUES TO DRY OUT FROM THE NORTH. MUCH COOLER TEMPS ON THURSDAY. CRAS BRINGS THE BAND OF SHOWERS CURRENTLY OVER NORTH MISSISSIPPI INTO FAR SOUTHERN MIDDLE TN BY 09/12Z BEFORE DISSIPATING IT. VFR SHOULD PREVAIL THROUGH THE PERIOD AT BNA AND CSV BUT A BRIEF PERIOD OF MVFR CAN BE EXPECTED DUE TO FOG AT CSV LATE TONIGHT. BOYD && .PREV DISCUSSION... /ISSUED 337 PM CDT WED SEP 8 2010/ SHORT TERM...IT WAS MOSTLY CLOUDY ACROSS THE SOUTHWESTERN TWO- THIRDS OF THE MID STATE THIS AFTERNOON, AND PARTLY CLOUDY OVER THE NORTHEAST. AT 300 PM, THE COLD FRONT/DEW POINT FRONT HAD BECOME NEARLY STATIONARY INVOF OF NASHVILLE, AND REACHED FROM NEAR CAMDEN, TO NEAR BRENTWOOD AND JAMESTOWN. EXPECT FRONT TO MOVE ONLY SLOWLY SOUTHWARD THROUGH 06Z, THEN PIVOT INTO A NORTHWEST-TO-SOUTHEAST ORIENTATION, FROM NEAR DOVER TO NEAR CHA. WILL KEEP A SLIGHT CHANCE FOR MEASURABLE RAIN SOUTH OF THE FRONT OVERNIGHT, WITH THE EXPECTATION FOR BETWEEN A TRACE AND A FEW HUNDREDTHS OF AN INCH. EXPECT HIGHEST DEW POINTS, AROUND 60, TO BE CONFINED TO OUR WESTERN COUNTIES, WHERE A CHANCE FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE. EXPECT DRY NORTHEAST FLOW ELSEWHERE, WITH AFTERNOON HIGHS ACROSS THE MID STATE RANGING FROM THE MID 70S PLATEAU, TO THE LOWER AND MIDDLE 80S ELSEWHERE. BY THURSDAY NIGHT, THE REMNANTS OF HERMINE PUSH INTO THE MIDDLE MISSISSIPPI VALLEY, BRINGING AN INCREASED CHANCE OF RAIN INTO OUR NORTHWESTERN COUNTIES, AS SURFACE FLOW STARTS TO TURN SOUTHEASTERLY ACROSS OUR AREA AND OLD STATIONARY FRONT OVER OUR WESTERN COUNTIES STARTS TO LIFT NORTHEASTWARD. BY FRIDAY, EXPECT AN INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS OVER THE NORTHWESTERN TWO- THIRDS OF OUR FORECAST AREA AS FRONT LIFTS NORTHWARD AS A WARM FRONT. FRIDAY NIGHT, DEEP MOISTURE LINGERS OVER OUR NORTHEASTERN AREAS, ALONG WITH A CONTINUED CHANCE FOR SHOWERS AND THUNDERSTORMS. ON SATURDAY, A COLD FRONT SWINGS IN FROM THE MISSISSIPPI VALLEY AND PRODUCE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE MID STATE. WARM AIR ADVECTION AHEAD OF IT WILL PRODUCE OUR WARMEST DAY OF THE PERIOD, WITH LOWER 90S SOUTHWEST AND MIDDLE AND UPPER 80S ELSEWHERE. LONG TERM...A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS WILL LINGER OVER EASTERN AREAS EARLY SUNDAY, BUT AFTER THAT EXPECT ANOTHER DRY AND COOLISH AIR MASS TO SETTLE IN ACROSS THE REGION THROUGH WEDNESDAY, WITH ANOTHER SURGE OF AUTUMN-LIKE WEATHER, WITH HIGHS MAINLY IN THE LOWER AND MIDDLE 80S AND LOWS IN THE MIDDLE AND UPPER 50S AT MOST LOCATIONS. EXPECT A DRY COLD FRONT LATE IN THE PERIOD TO USHER IN EVEN COOLER AIR, WITH HIGHS ON WEDNESDAY MOST AREAS ONLY IN THE UPPER 70S TO AROUND 80. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 290501 AAA AFDOHX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE NASHVILLE TN 1201 AM CDT WED SEP 29 2010 .UPDATE... UPDATED TO INCLUDE AVIATION DISCUSSION. && .AVIATION... UPPER LOW MOVING SLOWLY S ACROSS MID STATE AT THIS TIME...BUT ONLY GENERATING A FEW MID LEVEL CLOUDS. DRIER AIR WILL ADVECT INTO AREA AS LOW CONTINUES DRIFTING SLOWLY S INTO AL LATE TONIGHT AND WED. SOME FOG POSSIBLE AT CSV LATE TONIGHT AND EARLY WED. CRAS MODEL FORECAST INFRARED IMAGERY SHOWS MOISTURE ASSOCIATED WITH NORTHWARD MOVING TROPICAL SYSTEM OVER SE FL LATE WED AND WED NIGHT MAY MOVE NW INTO E TN WED NIGHT...POSSIBLY REACHING CSV AREA. BNA...VFR THROUGHOUT PERIOD. CSV...MVFR FOG POSSIBLE LATE TONIGHT UNTIL SHORTLY AFTER DAYBREAK. && .PREV DISCUSSION... /ISSUED 704 PM CDT TUE SEP 28 2010/ UPDATE... LIGHTER B/L WINDS TNGT W/PATCHY FOG. BEST COVERAGE OF FOG SHOULD BE IN THE PLAT/NEAR BODIES OF WATER. LOW TEMPS IN THE MID/UPR 40S. NO FROST YET BUT IT WON'T BE LONG. NO OTHER CHANGES PLANNED. PREV DISCUSSION... /ISSUED 213 PM CDT TUE SEP 28 2010/ DISCUSSION...HIGH PRESSURE STARTING TO WORK ITS WAY INTO MIDDLE TENNESSEE, ALTHOUGH SOME CLOUDS STILL LINGER AS THE UPPER TROUGH HAS YET TO PASS THROUGH THE MID STATE. STILL, TEMPERATURES ARE NOTICEABLY COOLER TODAY FOLLOWING A CHILLY MORNING. ONCE THE SHORTWAVE CLEARS OUT, LOOK FOR A NORTHWEST FLOW TO SET UP ALOFT AS A SURFACE RIDGE SITS TO OUR WEST, KEEPING US UNDER A NORTHERLY FLOW FOR THE NEXT SEVERAL DAYS AND HOLDING OUR TEMPERATURES GENERALLY BELOW NORMAL. EXPECT ANOTHER SHORTWAVE TO SWING THROUGH THE MID STATE ON SUNDAY, BRINGING SOME CLOUDS, BUT NO PRECIPITATION. THE NEXT 7 DAYS WILL BE DRY ACROSS THE MID STATE, AS THE SURFACE RIDGE ISN'T EXPECTED TO FINALLY SWING THROUGH UNTIL TUESDAY. THIS WILL KEEP TEMPERATURES COOL AT LEAST THROUGH THE END OF THE FORECAST PERIOD. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ STEIGERWALDT  FXUS64 KOHX 170013 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 613 PM CST THU DEC 16 2010 .UPDATE...FOR 17/00Z AVIATION FORECAST && .AVIATION... FRONTAL BOUNDARY LINGERING DOWN ALONG NORTHEAST CORNER OF ALABAMA NEAR SCOTTSBORO THEN UP JUST WEST OF CHATTANOOGA THEN EXTENDS THROUGH EASTERN TENNESSEE NEAR KNOXVILLE. POOR FLIGHT CONDITIONS (IFR) BEHIND THE FRONT ALL THE WAY BACK ACROSS MIDDLE TENNESSEE TO THE TENNESSEE RIVER DUE TO LOW CEILINGS AND VSBYS. ALTHOUGH OHX DOPPLER IS PPINE EXPECT LIGHT DRIZZLE TO CONTINUE THROUGH THE EVENING AT BNA AND THROUGH THE EVENING AND OVERNIGHT HOURS AT CSV. WITH FOG CONTINUING ALONG WITH LIGHT DRIZZLE WE COULD SEE SOME BLACK ICE CONDITONS OVERNIGHT AS TEMPS DIP BELOW FREEZING AND INTO THE MIDDLE 20S. WOULD NOT EXPECT MVFR AT BNA UNTIL MID TO LATE MORNING ON FRIDAY AND NOT AT CSV UNTIL LATE AFTERNOON. CRAS IS HINTING AT A VERY LIGHT WINTRY PRECIP EVENT FRIDAY EVENING ACROSS MID STATE. BOYD && .PREV DISCUSSION... /ISSUED 337 PM CST THU DEC 16 2010/ SHORT TERM (THRU SUN)... TNGT...LINGERING MOISTURE AND H8 TEMPS AROUND 0 C COULD GENERATE A FEW FLURRIES/PATCHY DRIZZLE THIS EVENING IN THE NORTH. MAINLY A CLOUDY SKY W/LOWS MID-UPR 20S. SFC HIGH PRES ACR W CANADA-CNTL PLAINS WL CONTINUE TO FEED COLD AIR INTO MID TN FRI. HIGHER UP...MODELS SHIFT A H5 S/W TROF OVR THE REGION FRI NGT-SAT WITH A CHANCE OF PCPN. MOISTURE LIMITED W/CHC SPRINKLES AND FLURRIES AT THIS POINT. SFC PATTERN CHANGES LITTLE AS POLAR JET DROPS SOUTH SAT. HIGHS SHOULD REMAIN IN THE MID-UPR 30S THIS WEEKEND. LONG TERM (MON-THU)... WARMER MON AS LOW PRES DEVELOPS IN THE SOUTHERN PLAINS. SFC LOW MOVES INTO THE REGION MON NGT-TUE W/CHC OF RAIN. COULD BE A RAIN SNOW MIX NORTH NEAR THE KY LINE. COLDER AIR RUSHES IN AS MOISTURE DEPARTS TUE AFTERNOON. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 170535 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 1135 PM CST THU DEC 16 2010 .UPDATE...FOR AVIATION FORECAST 17/06Z && .AVIATION... COLD FRONT NOW WELL EAST OF PLATEAU WITH LOW CLOUDS BACK TO THE MISSISSIPPI RIVER WITH IFR CONDITIONS FROM THE PLATEAU TO THE TENNESSEE RIVER. FREEZING FOG HAS DEVELOPED ALONG THE PLATEAU WITH CSV DOWN TO 1/4SM IN FZFG AT THIS TIME. DONT EXPECT MUCH IN THE WAY OF IMPROVEMENT AT CSV UNTIL AFTER DAYBREAK. WITH FREEZING FOG ALONG THE PLATEAU EXPECT BLACK ICE TO FORM IN THIS AREA ON ROADWAYS. EXPECT CSV TO STAY IFR GOOD PART OF THE MORING BUT GO MVFR DURING THE AFTERNOON AND VFR TOWARDS SUNSET ON FRIDAY. AS FOR BNA FEEL MVFR WILL HOLD IN GENERAL THROUGH THE OVERNIGHT HOURS BUT AM SEEING HOLDS IN LOW DECK TO OUR WEST AT THIS TIME AND IT IS POSSIBLE WHERE SOME TEMPORARY CLEARING TAKES PLACE FOG WILL FORM QUICKLY AND LOWER VSBYS DOWN TO IFR CONDITIONS WITH BLACK ICE FORMING ON ROAD SURFACES. BNA SHOULD GO VFR AFTER SHORTLY AFTER SUNRISE. LOW CONFIDENCE ON BNA TERMINAL FORECAST FIRST 6 HOURS. LOOKING AT CRAS AND THE MOISTURE DEEPENING IN THE LATEST MODEL RUNS BELIEVE FLURRIES ARE POSSIBLE FRIDAY NIGHT AND SATURDAY MORNING HERE IN MIDDLE TENNESSEE BROAD UPPER TROUGH APPROACHES FROM THE WEST. BOYD && .PREV DISCUSSION... /ISSUED 941 PM CST THU DEC 16 2010/ UPDATE... LOW CLOUDS CONTINUE TO HANG ACROSS THE REGION THIS EVENING...AND THESE CLOUDS LOOK TO BE HERE ALL NIGHT. COLD ADVECTION CONTINUES. PATCHY DENSE FOG SHOWING UP ON THE PLATEAU AS WELL AS PATCHY DRIZZLE. AS TEMPS CONTINUE TO FALL OVERNIGHT...EXPECTED DRIZZLE MAY FREEZE. WILL ADD PATCHY FOG/FZDZ TO EAST. LEAVE REMAINING AS IS FOR NOW. PREV DISCUSSION... /ISSUED 613 PM CST THU DEC 16 2010/ UPDATE...FOR 17/00Z AVIATION FORECAST AVIATION... FRONTAL BOUNDARY LINGERING DOWN ALONG NORTHEAST CORNER OF ALABAMA NEAR SCOTTSBORO THEN UP JUST WEST OF CHATTANOOGA THEN EXTENDS THROUGH EASTERN TENNESSEE NEAR KNOXVILLE. POOR FLIGHT CONDITIONS (IFR) BEHIND THE FRONT ALL THE WAY BACK ACROSS MIDDLE TENNESSEE TO THE TENNESSEE RIVER DUE TO LOW CEILINGS AND VSBYS. ALTHOUGH OHX DOPPLER IS PPINE EXPECT LIGHT DRIZZLE TO CONTINUE THROUGH THE EVENING AT BNA AND THROUGH THE EVENING AND OVERNIGHT HOURS AT CSV. WITH FOG CONTINUING ALONG WITH LIGHT DRIZZLE WE COULD SEE SOME BLACK ICE CONDITONS OVERNIGHT AS TEMPS DIP BELOW FREEZING AND INTO THE MIDDLE 20S. WOULD NOT EXPECT MVFR AT BNA UNTIL MID TO LATE MORNING ON FRIDAY AND NOT AT CSV UNTIL LATE AFTERNOON. CRAS IS HINTING AT A VERY LIGHT WINTRY PRECIP EVENT FRIDAY EVENING ACROSS MID STATE. BOYD PREV DISCUSSION... /ISSUED 337 PM CST THU DEC 16 2010/ SHORT TERM (THRU SUN)... TNGT...LINGERING MOISTURE AND H8 TEMPS AROUND 0 C COULD GENERATE A FEW FLURRIES/PATCHY DRIZZLE THIS EVENING IN THE NORTH. MAINLY A CLOUDY SKY W/LOWS MID-UPR 20S. SFC HIGH PRES ACR W CANADA-CNTL PLAINS WL CONTINUE TO FEED COLD AIR INTO MID TN FRI. HIGHER UP...MODELS SHIFT A H5 S/W TROF OVR THE REGION FRI NGT-SAT WITH A CHANCE OF PCPN. MOISTURE LIMITED W/CHC SPRINKLES AND FLURRIES AT THIS POINT. SFC PATTERN CHANGES LITTLE AS POLAR JET DROPS SOUTH SAT. HIGHS SHOULD REMAIN IN THE MID-UPR 30S THIS WEEKEND. LONG TERM (MON-THU)... WARMER MON AS LOW PRES DEVELOPS IN THE SOUTHERN PLAINS. SFC LOW MOVES INTO THE REGION MON NGT-TUE W/CHC OF RAIN. COULD BE A RAIN SNOW MIX NORTH NEAR THE KY LINE. COLDER AIR RUSHES IN AS MOISTURE DEPARTS TUE AFTERNOON. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 190522 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 1122 PM CST FRI FEB 18 2011 .UPDATE...FOR 19/06Z AVIATION FORECAST && .AVIATION... SCATTERED SHOWERS HAVE BEEN DIMINSHING RATHER QUICKLY LAST HOUR AND EXPECT TREND TO CONTINUE. COLD FRONT ACROSS NORTHERN MISSISSIPPI/ALABAMA AT LATE EVENING WILL REMAIN STATIONARY THROUGH SATURDAY. CURRENTLY CLEARING LINE JUST NORTH OF MID STATE WILL SINK SOUTHWARD AFTER MIDNIGHT BUT ANY CLEARING WILL BE SHORT LIVED AS ISENTROPIC LIFT ALONG THE 295 KELVIN SURFACE WILL GET UNDERWAY LATE TONIGHT THAT WILL BRING A RETURN OF CLOUDS FROM THE SOUTHWEST TO THE MID STATE BETWEEN 19/12Z AND 19/15Z IN BNA AND AROUND 19/18Z TO CSV. THIS IS BEST DISPLAYED IN LATEST CRAS RUN WHICH SEEMS TO HAVE A GOOD HANDLE ON THIS DEVELOPMENT. BANKING ON DRIER AIR NOW OVER SOUTHERN KENTUCKY TO WORK DOWN INTO MID STATE AFTER MIDNIGHT AND KEEP FOG FROM FORMING AT BNA BUT CSV MAY GET A TEMPO PERIOD OF FOG AFTER MIDNIGHT UNTIL ABOUT 19/10Z TAKING THE VSBY DOWN TO 5SM BEFORE DRIER AIR MOVES IN ALONG THE PLATEAU. BOYD && .PREV DISCUSSION... /ISSUED 842 PM CST FRI FEB 18 2011/ UPDATE...SHOWERS ARE NOT SINKING SWD AS FAST AS ORIGINAL FORECAST ANTICIPATED. HAVE SLOWED THE PROCESS DOWN ACCORDINGLY. REMAINDER ALL OK. PREV DISCUSSION... /ISSUED 553 PM CST FRI FEB 18 2011/ UPDATE...FOR 19/00Z AVIATION FORECAST AVIATION... TEMPS CURRENTLY IN THE MID 50S ACROSS NORTHERN MIDDLE TENNESSEE WITH MID 60S ACROSS NORTHERN ALABAMA. ANALYZED COLD FRONT ACROSS FAR SOUTHERN MIDDLE TENNESSEE AT 18/23Z WITH POST FRONTAL SHOWERS ALONG AND NORTH OF INTERSTATE 40 AND IN SOUTHERN KENTUCKY. SKIES HAVE CLEARED ACROSS THE NORTH HALF OF KENTUCKY NORTHWARD AND BACK INTO THE MISSOURI OZARKS. MODELS SLIP FRONT INTO NORTH ALABAMA BY 19/06Z AND STALL IT ACROSS CENTRAL ALABAMA AROUND 19/18Z BEFORE TURNING IT AROUND AS A WARM FRONT LATE SATURDAY NIGHT. BASICALLY LOOKING FOR MVFR AT BNA THROUGH ABOUT 19/05Z DUE TO CEILINGS/VSBYS AND AT CSV UNTIL 19/06Z WITH LATE NIGHT FOG DEVELOPING AT CSV FROM 19/08Z THROUGH 19/14Z. WIND MAY STAY UP ENOUGH TO KEEP FOG FROM FORMING AT BNA PLUS DRIER AIR WILL BE FILTERING IN SO DID NOT INCLUDE FOG AT BNA FOR THOSE REASONS. WHAT BREAK WE HAVE IN CLOUDS LATER TONIGHT WILL BE SHORT LIVED AS THEY RETURN QUICKLY SATURDAY MORNING ALONG THE 290 KELVIN ISENTROPIC SURFACE. BOYD PREV DISCUSSION... /ISSUED 331 PM CST FRI FEB 18 2011/ DISCUSSION... FRONTAL BOUNDARY LOCATED ROUGHLY ALONG THE TN/KY BORDER. A SOLID BAND OF SHOWERS IN ASSOCIATION WITH THE BOUNDARY CAN BE SEEN MOVING SOUTHWARD AT THIS TIME. COLD FRONT EXPECTED TO MOVE ACROSS THE CWA TONIGHT. THUS...WILL CARRY 20-40 POPS FOR THE MID STATE FOR TONIGHT. THE BOUNDARY WILL SLOW DOWN AS IT MOVES JUST SOUTH OF THE CWA ON SATURDAY. THUS...A SLIGHT CHANCE OF SHOWERS WILL CONTINUE INTO THE DAY ON SATURDAY. ANY MEASURABLE PRECIP WILL END BY SATURDAY NIGHT. HOWEVER...LOW LEVEL MOISTURE AND PERHAPS A FEW SPRINKLES WILL CONTINUE ON SUNDAY. ADDITIONALLY...WE WILL SEE OUR SOUTHERLY WIND SPEEDS BEGIN TO INCREASE AS A STORM SYSTEM GETS CRANKED UP OVER THE MIDWEST. THE ASSOCIATED COLD FRONT WILL MOVE THROUGH ON MONDAY. THUS...RAIN CHANCES TO RETURN BY MONDAY. FOR THE NEAR TERM TEMPS...GFS NUMBERS LOOK BEATABLE TONIGHT AND SATURDAY. SFC ANALYSIS IS NOT SHOWING COLD AIR NORTH OF BOUNDARY RIGHT NOW. THEREFORE...THE 37F LOW AT BNA LOOKS TOO COOL. SATURDAY AFTERNOON...WE SHOULD KEEP THE CLOUDINESS SO I WILL UNDERCUT THE GFS MAX TEMPS. IN THE EXT FCST...WE'LL SEE CAA RETURN ON MON NT...BUT SOUNDINGS STILL KEEP FREEZING LEVELS TOO HIGH FOR ANY FROZEN PRECIP. WE'LL SEE A WARM FRONT MOVE ACROSS THE AREA TOWARD THE END OF THE WEEK. AS MOISTURE RETURNS...WE'LL SEE ANOTHER ROUND OF SHOWERS BY FRIDAY. NEAR NORMAL TEMPS WILL GIVE WAY TO WARMER THAN NORMAL VALUES BY NEXT WEEKEND. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 101201 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 601 AM CST THU MAR 10 2011 .UPDATE...FOR 10/12Z AVIATION FORECAST && .AVIATION... SURFACE LOW ALONG SOUTHERN APPALACHIANS THIS MORNING WILL CONTINUE EASTWARD WHILE UPPER TROUGH DIGS DOWN ACROSS OUR AREA KEEPING CLOUDS AND LIGHT PRECIP GOING THROUGH MID-DAY AT BNA AND INTO THE AFTERNOON AT CSV. CRAS HOLDS ONTO LOW CLOUDS THROUGH 11/06Z AT BNA AND THROUGH THE ENTIRE FORECAST PERIOD AND BEYOND AT CSV. BOYD && .PREV DISCUSSION... /ISSUED 349 AM CST THU MAR 10 2011/ DISCUSSION... FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED. FORECAST QUANDARIES...VERY INTERESTING REGIONAL RADAR DISPLAY AS OF 09Z...WITH LIGHT RAIN MOVING IN FROM THE NW...AND LIGHT RAIN MOVING S TO N ACROSS THE CUMBERLAND PLATEAU REGION. THIS IS LIKELY IN ASSOCIATION WITH UPPER LEVEL TROUGH...AND ASSOCIATED EMBEDDED UPPER LEVEL LOW...BEGINNING TO MOVE ACROSS THE MID STATE. EXPECT UPPER LEVEL FEATURES TO SLOWLY PROGRESS W TO E ACROSS THE MID STATE TODAY...PROVIDING FOR A CONTINUANCE OF CLDY SKIES AND KEEPING TEMPS MAINLY IN THE LOW TO MID 40S. DO NOT EXPECT A LOT OF ACCUMULATING RAINFALL WITH THIS PASSAGE...AND WILL GO WITH A CHANCE W TO LIKELY ACROSS PLATEAU REGION FOR TODAY. TEMPS MAY DROP ENOUGH THIS MORNING FOR A RAIN/SNOW MIXTURE ACROSS PORTIONS OF THE N CUMBERLAND PLATEAU ALSO. AS UPPER LEVEL FEATURES MOVE TO THE E TONIGHT...THERE WILL BE A SLIGHT CHANCE OF LIGHT RAINFALL FOR LOCATIONS MAINLY ALONG AND EAST OF I-65... WITH AGAIN THE CHANCE OF A RAIN/SNOW MIXTURE ACROSS N PORTIONS OF THE CUMBERLAND PLATEAU. A OVERALL BETTER CHANCE FOR SNOW MAY OCCUR ACROSS THE ENTIRE PLATEAU REGION AFTER MIDNIGHT TONIGHT...WITH SOME SLIGHT ACCUMULATIONS POSSIBLE. AS FIRST MENTIONED IN YESTERDAY AFTERNOON'S AFD...WILL CONTINUE WITH REASONING OF ACCUMULATIONS OF UP TO ONE HALF OF AN INCH POSSIBLE ACROSS N PORTIONS OF THE CUMBERLAND PLATEAU. WILL GO WITH LOWS IN THE LOWER 30S...UPPER 20S PLATEAU. LOOK FOR DRY CONDITIONS THRU THE UPCOMING WEEKEND...WITH A GRADUAL WARMUP IN TEMPS TO MORE SEASONABLE NORMS FOR THIS TIME OF YEAR... WITH HIGHS MAINLY IN THE LOW TO MID 60S...AND LOWS AROUND 40. SOME TIMING DIFFERENCES IN MODEL SOLUTIONS AS NEXT WEEK PROGRESSES... AND WENT WITH A CONSENSUS SOLUTION IN AGREEMENT WITH OUR NEIGHBORING OFFICES...WITH HIGHS WARMING THRU THE 60S...LOWS RISING INTO THE MID TO UPPER 40S...WITH A SLIGHT CHANCE TO CHANCE OF SHWRS SUN NIGHT THRU MOST OF THE DAY ON TUE. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 191503 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 1003 AM CDT SAT MAR 19 2011 .UPDATE... COOL FRONT ALL THE WAY DOWN IN CENTRAL ALABAMA AT 19/15Z WITH NORTHERLY FLOW WORKING INTO MID STATE. TEMPS ARE IN THE 40S NORTH OF OHIO RIVER WITH LOWER 50S ACROSS SOUTHERN KY. BULK OF STRATOCUMULUS SOUTH OF INTERSTATE 40 AND SLIPPING SOUTHWARD WITH TIME. ALTHOUGH CONTRAST IS POOR...CRAS HAS LOW STUFF WORKING SOUTH DURING THE DAY WHILE BRINGING MID AND UPPER LEVEL CLOUDS BACK ACROSS NORTHERN AREAS OF MID STATE EARLY THIS EVENING. BELIEVE ONCE SUN GETS OUT WE WILL SEE TEMPS START TO CLIMB BUT MAY FALL SHORT OF CURRENT FORECAST SO MAY HAVE TO UPDATE AND TRIM AFTERNOON HIGHS DOWN A BIT. IF LOW LEVEL INVERSION COULD GET WIPED OUT THROUGH MIXING WE WOULD MAKE CURRENT TEMP FORECAST SO WILL WAIT AND GIVE FORECAST A CHANCE TO FLY. ALSO...CANT RULE OUT A SHOWER NEAR ALABAMA BORDER BUT DOESNT LOOK LIKE THERE WILL BE MUCH. BOYD && .PREV DISCUSSION... /ISSUED 625 AM CDT SAT MAR 19 2011/ UPDATE...FOR 12Z AVIATION DISCUSSION. AVIATION...12Z AVIATION DISCUSSION. UNCERTAINTIES...CONTINUED SWD PROGRESSION OF FRONTAL/MOISTURE MOVEMENT...EROSION OF LOW LEVEL VFR CEILINGS...MID LEVEL CEILING DEVELOPMENT AOA 20/00Z-20/12Z...ALONG WITH LOCAL IMPACTS. WITH WEAK COLD FRONT EXPECTED TO CONTINUE TO MOVE SWD...AND A REDUCTION EXPECTED IN POST FRONTAL MOISTURE POTENTIAL...WILL GO WITH VCSH REMARKS ONLY THRU 19/18Z. EXPECT AS SFC/LOW LEVEL RIDGING INFLUENCES BECOME MORE PRONOUNCED FROM A0A 19/18Z-20/00Z...MID LEVEL BKN AC CEILINGS WILL BE PREVALENT AT BNA/CSV. AS MID LEVEL MOISTURE CONTINUE TO INCREASE THRU 20/12Z...AC DECK WITH BECOME OVC IN NATURE. PREV DISCUSSION.../ISSUED 326 AM CDT SAT MAR 19 2011/ DISCUSSION... SCATTERED LIGHT SHOWERS OVER CENTRAL KY ATTM. WEAK FRONTAL BOUNDARY IS NOW ACROSS SOUTHERN MIDDLE TN. THUS...THE ASSOCIATED PRECIP IS POST FRONTAL. A CLOSE LOOK AT THE GFS AND NAM 850 MB MOISTURE PROFILE SHOWS THAT THE MODELS ARE TOO FAR SOUTH WITH THE BETTER MOISTURE. ADDITIONALLY...WITH TIME THE MOISTURE AXIS OVER KY WILL SINK SLOWLY SOUTHWARD BUT IT WILL DECREASE IN TERMS OF THE MOISTURE LEVELS. THEREFORE...FOR TODAY...I WILL INCLUDE A MOSTLY CLOUDY SKY FOR THE MORNING WITH A SLT CHANCE OF SHOWERS. THEN... PARTLY SUNNY SKIES AND NO MENTION OF PRECIP FOR THE AFTERNOON. THE WEAK COLD FRONT WILL MOVE SOUTHWARD INTO NORTHERN AL TODAY. IT WILL THEN RETURN QUICKLY NORTHWARD AS A WARM FRONT ON SUNDAY. WITHIN THE WESTERLY FLOW ALOFT...A WEAK DISTURBANCE MAY TRAVERSE THE AREA AND PROVIDE A SLIGHT CHANCE OF SHOWERS OR TSTMS FOR SUNDAY. OTW...PARTIAL CLOUDINESS THROUGH MONDAY WITH LITTLE IN THE WAY OF PRECIP. FOR THE NEAR TERM TEMPS...MAV NUMBERS LOOK REASONABLE SO WONT DIFFER BY MUCH. ABOVE NORMAL TEMPS TO PREVAIL. IN THE EXT FCST...STILL LOOKING AT A MID WEEK STORM SYSTEM. THE MAIN FEATURE WILL BE A WEST TO EAST COLD FRONT THAT WILL SETTLE SOUTHWARD AND BRING SHOWERS AND TSTMS TO THE AREA TUES NT THROUGH WED NT. COLDER TEMPS TO FOLLOW. EURO SOLUTION LOOKS WET ON FRIDAY BUT WILL CONTINUE WITH THE CURRENT FCST WHICH LEANS TOWARD THE DRIER GFS SOLUTION. FOR THE EXT TEMPS...MEX NUMBERS LOOK BEATABLE AT TIMES. WILL GO WARMER IN THE PRE FRONTAL SECTOR ON TUES/TUES NT...COOLER POST FRONTAL. HOPING TO SCORE BIG AS THE EURO SOLUTION MATCHES UP WELL WITH THE WED NT FROPA. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 260508 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 1208 AM CDT SAT MAR 26 2011 .UPDATE...FOR 26/06Z AVIATION FORECAST && .AVIATION... BEGINNING TO SEE SHOWER ACTIVITY INCREASING OVER NORTHERN MISSISSIPPI AS ADVERTISED BY EARLIER MODELS INCLUDING GFS AND RAPID UPDATE (HRRR). CRAS ALSO BREAKS RAIN OUT FIRST ACROSS NORTHERN MISSISSIPPI SHORTLY AFTER MIDNIGHT AND WORKS IT ACROSS SOUTHERN MIDDLE TENNESSEE NEAR ALABAMA BORDER IN THE OVERNIGHT. QUASI-STATIONARY FRONT ACROSS NORTHERN MISSISSIPPI AND NORTHERN ALABAMA. FRONT WILL SLIP SLOWLY NORTHWARD BUT NOT MUCH FARTHER THAN THE ALABAMA BORDER. THEREFORE WILL ONLY MENTION LIGHT RAIN IN BOTH BNA AND CSV THROUGH THE PERIOD. EXPECT ANY TSTMS TO REMAIN OVER SOUTHERN AREAS. BOYD && .PREV DISCUSSION... /ISSUED 918 PM CDT FRI MAR 25 2011/ DISCUSSION...CURRENT PRECIP HAS THINNED OUT A GOOD DEAL IN THE PAST FEW HOURS. FRONT IS STILL WELL TO THE SOUTH OVER NORTH MS/AL/GA. ALL MODELS REDEVELOP PRECIP OVER THE AREA OF THE FRONT AND A FEW DEGREES TO THE NORTH OF THE FRONT LATE TONIGHT. HAD CONSIDERED LOWERING POPS...BUT DIDN'T WANT TO GIVE THE WRONG IMPRESSION SINCE THE SFC LOW IS STILL TO OUR SOUTHWEST...OVER THE ARKLATEX. MORE PRECIP SHOULD DEVELOP BY 09-10Z OVER THE AREA WITH PRECIP CONTINUING THROUGH THE DAY TOMORROW AS THE SFC LOW MOVES ENEWD ACROSS NORTHERN MS/AL/GA. WILL KEEP THE CURRENT ZONE PACKAGE WITH THE EXPECTATION OF MORE PRECIP TO COME. PREV DISCUSSION... /ISSUED 650 PM CDT FRI MAR 25 2011/ UPDATE...FOR 26/00Z AVIATION FORECAST AVIATION... QUASI-STATIONARY FRONT LAYING BETWEEN HUNTSVILLE AND BIRMINGHAM ALABAMA THEN BACK TO JUST NORTH OF TUPELO MISSISSIPPI...TO JUST SOUTH OF MEMPHIS...THEN BACK ACROSS SOUTHERN ARKANSAS INTO NORTHEASTERN OKLAHOMA. TEMPS JUST NORTH OF THE FRONT ARE CHILLY AND IN THE 40S ACROSS TENNESSEE WHILE JUST SOUTH OF THE FRONT TEMPS ARE IN THE 60S AND 70S. WILL NEED TO KEEP CLOSE TABS ON FRONTAL POSITION NEXT 24 HOURS AS MUCH OF THE SIGNIFICANT WEATHER WILL BE FOCUSED ALONG THE FRONTAL BOUNDARY. EVERYTHING I'VE LOOKED AT TELLS ME THE FRONT WILL REMAIN GENERALLY ACROSS NORTH ALABAMA...POSSIBLY REACHING THE TENNESSEE/ALABAMA BORDER SATURDAY EVENING. BOYD PREV DISCUSSION... /ISSUED 343 PM CDT FRI MAR 25 2011/ DISCUSSION... IN THE NEAR SHORT TERM...THE EURO MODEL CLEARLY HAS THE BEST GRASP ON THIS CURRENT SYSTEM. MODELS ARE LOOKING AS THOUGH THEY WILL MATCH UP A LITTLE BETTER OVER THE NEXT FEW DAYS HOWEVER. STILL EXPECTING OVERRUNNING TO CONTINUE INTO TONIGHT. WE HAD A FEW REPORTS OF ICE PELLETS ACROSS OUR NORTHWEST EARLIER TODAY. A CLOSE LOOK AT THE SOUNDING DOES INDICATE WET BULB WARMING WITH TIME INTO THIS EVENING. THUS...NOT EXPECTING MUCH MORE IN THE WAY OF ANY ICE PELLET ACTIVITY. UPCOMING STORM SYSTEM IS STILL EXPECTED TO BRING RAINFALL TO THE AREA SATURDAY INTO SATURDAY NIGHT. THE STORM TRACK APPEARS TO BE A SOUTHERLY ONE WHEREBY THE LOW WILL TRACK ACROSS NORTHERN AL. THIS WILL EQUATE TO A LESSER CHANCE OF TSTMS WHILE TEMPS WILL BE COOLER. A LOOK AT ALL THE MODELS SUPPORT THE SOUTHERLY TRACK. THEREFORE...FOR THE FORECAST I WILL INCLUDE JUST A CHANCE OF T SOUTH AND NO T NORTH. RAINFALL AMOUNTS LOOK AS THOUGH A HALF INCH OR SO CAN BE EXPECTED AT MOST AREAS FOR TONIGHT THROUGH SATURDAY NT. THE SHOWERS WILL END EARLY SUNDAY. FOR THE NEAR TERM TEMPS...I WILL BE UNDERCUTTING THE MAV MAX TEMPS...PARTICULARLY ON SATURDAY AS A WET AND RAW PATTERN WILL REMAIN. IN THE EXT FCST...A RETURN FLOW WITH A SHORT LIVED WARMING TREND WILL SET UP ON MONDAY. A STORM SYSTEM WILL THEN PULL ACROSS THE MID MS VALLEY AND TRACK ACROSS KY BY WEDNESDAY. THIS WILL BRING SHOWERS AND TSTMS BACK TO THE AREA FOR THE MIDDLE OF THE WEEK. THIS SYSTEM WILL PLACE THE MID STATE IN MORE OF THE WARM SECTOR. THUS...IT WILL NEED TO BE WATCHED FOR THE POTENTIAL OF SVR STORMS. OTW...HIGH TEMPS WILL DROP BACK DOWN INTO THE 50S BY THE END OF THE WEEK. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 211514 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 1014 AM CDT THU APR 21 2011 .UPDATE... SURFACE FRONT THIS MORNING DRAPED DOWN ACROSS NORTHERN ALABAMA DOWN THROUGH NORTH CENTRAL MISSISSIPPI INTO EAST TEXAS. TEMPS NORTH OF FRONT GENERALLY IN THE 50S THIS MORNING ACROSS MIDDLE TENNESSEE. VISBLE SHOWING SOME SUN BREAKING THROUGH CLOUD DECK AT TIMES. CURRENT FORECAST LOOKS ON TRACK AND NO CHANGES PLANNED AT THIS TIME. THIS BOUNDARY WILL BECOME A BIG PLAYER OVER THE NEXT SEVERAL DAYS IN TERMS OF RAINFALL NOT ONLY HERE IN MIDDLE TN BUT ACROSS OUR REGION. THE BOUNDARY IS FORECAST BY GFS TO START BACK NORTH TONIGHT AND IS PROGGED TO LAY ALONG THE TENNESSEE/KENTUCKY BORDER BY 12Z FRIDAY AND THEN LIFT NORTHWARD INTO THE OHIO RIVER VALLEY BY 00Z SATURDAY. EXPECT SHOWERS AND A FEW THUNDERSTORMS OVERNIGHT TONIGHT AS FRONT LIFTS UP THROUGH THE MID STATE. FRONT WILL BE NORTH OF MID STATE DURING THE DAY ON FRIDAY SO EXPECT HIGHER POPS TO BE NORTH OF KENTUCKY BORDER ON FRIDAY. HEAVY RAIN EVENT SETTING UP FOR FRIDAY NIGHT INTO SATURDAY ACROSS SOUTHEAST MISSOURI...WESTERN KY AND NORTHEAST ALONG THE OHIO RIVER BASED ON GFS. CRAS HAS THE HIGHER QPFS CLOSER TO THE MID STATE THAN GFS DOES FOR FRIDAY NIGHT AND SATURDAY. BOYD && .PREV DISCUSSION... /ISSUED 505 AM CDT THU APR 21 2011/ AVIATION 12Z DISCUSSION... FRONTAL BOUNDARY TO OUR SOUTH WILL WORK BACK TO THE NORTH AS A WARM FRONT BY THIS EVENING. WE WILL THEREFORE SEE A RETURN OF SHOWERS AND TSTMS...MAINLY AFTER 00Z. CIGS WILL DROP BELOW 3KFT AFTER 08Z WITH VSBYS IN THE 3-5SM RANGE. PREV DISCUSSION... /ISSUED 359 AM CDT THU APR 21 2011/ DISCUSSION... YESTERDAYS PASSING FRONTAL BOUNDARY NOW JUST SOUTH/EAST...WHERE SHWRS/ STORMS CONTINUE TO DEVELOP ALONG/NEAR. ML/UL FLOW REMAINS GENERALLY ZONAL WHICH IS KEEPING FRONT FROM REALLY MAKING ANY SIGNIFICANT FURTHER PROGRESS SOUTH. NOT MUCH CHANGE EXPECTED IN ML/UL FLOW TODAY...WHICH WILL KEEP BOUNDARY QUASI-STATIONARY. MODERATE MOISTURE HOWEVER CONTINUES TO LINGER ACROSS THE CWA...AS WELL AS DECENT INSTABILITY JUST ABOVE SHALLOW COLD AIR. WEAK ML UVV EXPECTED TO PASS LATER TODAY...WHICH WILL HELP SET OFF ANOTHER ROUND OF SCT SHWRS/STORMS...ESPECIALLY EXTREME SOUTH IN CLOSER PROXIMITY OF BOUNDARY. BOUNDARY MAKES NORTHWARD PUSH TONITE AS IT GETS CAUGHT UP IN DEEPENING PLAINS LOW...SETTING UP FROM NEAR THE TN/KY BORDER DOWN ACROSS THE PLATEAU AROUND 12Z FRI. THIS WILL TRANSITION AREA BACK INTO WARM SECTOR...AND DEEPER LAYER OF INSTABILITY. ENHANCED LL FORCING FROM BOUNDARY AND INCREASED INSTABILITY EXPECTED TO BRING NUMEROUS SHWRS/STORMS TO THE AREA THIS EVENING...TAPERING OVERNIGHT AS FOCUS SHIFTS INTO KY. FRONTAL BOUNDARY MOVES FURTHER NORTH ON FRI...EVENTUALLY ORIENTING ITSELF ACROSS THE OH VALLEY DOWN INTO THE SOUTHERN PLAINS...WHERE IT GOES MORE PARALLEL TO ML/UL FLOW. VIRTUALLY NO CHANGE IN ML/UL FLOW PATTERN WILL KEEP BOUNDARY NORTH/WEST INTO THE FIRST PART OF NEXT WEEK WHEN UL LOW/TROF FINALLY GET INTO THE PICTURE. THUS STARTING FRI POPS WILL RAMP DOWN THRU MON EVENING AS TEMPS GO ABOVE SEASON NORMALS. ON TUE...FRONT AND SHARP ML/UL TROF FINALLY MAKE SLOW EASTWARD PUSH INTO THE MID-STATE...BUT TAKE ALL OF WED TO MOVE EAST. THIS COULD BE POTENTIAL BIG RAIN IF SOLUTION WORKS OUT. WILL RAMP POPS BACK UP TUE INTO MID-WEEK. HYDROLOGY... OVERALL...EXPECTED PCPN AMOUNTS NEXT 24-36 HOURS STILL BELOW FLOOD GUIDANCE HOWEVER...LOCALIZED FLOODING NOT OUT OF THE QUESTION... ESPECIALLY TONITE WITH FRONT ON THE MOVE. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 010001 AFDOHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 701 PM CDT SAT APR 30 2011 .MESOSCALE UPDATE... SHORT LINE OF THUNDERSTORMS CURRENTLY MOVING THROUGH FAR WESTERN KENTUCKY HAS WEAKENED DURING THE LAST HOUR WHILE CONTINUING TO MOVE NORTHEAST AT A PRETTY GOOD CLIP. LINE GENERALLY ORIENTED ALONG WESTERN SIDE OF HIGHER THETA E AXIS AND IN THE GRADIENT AREA. BOYD && .PREV DISCUSSION... /ISSUED 608 PM CDT SAT APR 30 2011/ UPDATE... UPDATED GRIDS/ZONES TO REMOVE AFTERNOON WORDING. COLD FRONT BACK JUST WEST OF FORT SMITH ARKANSAS. 60 DEGREE DEWPOINTS UP AHEAD OF FRONT INTO SOUTHERN MISSOURI. LINE OF THUNDERSTORMS CURRENTLY ALONG THE MISSISSIPPI RIVER MOVING EAST AT A PRETTY GOOD CLIP. RAPID REFRESH AND CRAS ARE BOTH SLOWER IN BRINGING PRECIP EASTWARD TONIGHT. OTHERWISE NO CHANGES TO FORECAST AT THIS TIME. BOYD PREV DISCUSSION... /ISSUED 337 PM CDT SAT APR 30 2011/ DISCUSSION... MOSTLY SUNNY SKIES IN PLACE THIS AFTERNOON. SAT IMAGERY DOES SHOW THAT CHANGES ARE AHEAD AS A LARGE AREA OF CLOUDINESS COVERS MUCH OF THE LOWER AND MID MS VALLEYS. THIS MOISTURE IS IN ASSOCIATION WITH THE NEXT WEATHER SYSTEM WHICH WILL BE HEADING OUR WAY OVER THE NEXT 24 TO 48 HRS. STILL LOOKING AT THE APPROACH OF A SLOW MOVING COLD FRONT LATE TONIGHT AND THROUGH MONDAY. THE ACTUAL FROPA IS EXPECTED BY MONDAY NIGHT. WE WILL GENERALLY SEE INCREASING RAIN CHANCES EXCEPT FOR A SLIGHT BREAK SUNDAY NIGHT. ON SUNDAY NIGHT...THE PVA INFLUENCE BECOMES MORE NEUTRALIZED SO THAT WE SEE A DECREASE IN CONVERGENCE ALONG THE BOUNDARY. THIS WILL BE SHORT LIVED HOWEVER AS IT STRENGTHENS AGAIN ON MONDAY. DEVELOPING UPPER TROUGH WILL SWING THROUGH ON TUESDAY AND THEREBY BRING A FINAL ROUND OF RAINFALL TO THE AREA. OVERALL QPF AMOUNTS LOOK TO RANGE FROM 3 1/2 INCHES FAR NORTHWEST TO ABOUT 1 INCH ACROSS THE SOUTHERN PLATEAU. AS FOR SEVERE POTENTIAL...WE ARE NOT OUTLOOKED AS THE SLT CHC FOR SVR REMAIN TO OUR WEST. WILL REISSUE THE HYDRO OUTLOOK(ESF) BUT WILL INCLUDE ONLY THE WESTERN QUARTER OR SO OF THE MID STATE. IN THE EXT FCST...A RETURN TO A DRIER REGIME IS INDICATED. TEMPS WILL BE NEAR SEASONAL LEVELS FOR EARLY MAY. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01  FXUS64 KOHX 251559 AAA AFDOHX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE NASHVILLE TN 1059 AM CDT WED MAY 25 2011 .UPDATE... MORNING ANALYSES DEPICT A 500 MB LOW OVER KS AT 12Z WITH ASSOCIATED 200 TO 300 MB JET MAX LOCATED S OF LOW OVER OK AND N TX AREA. MODELS FORECAST THE UPPER LOW TO MOVE E TODAY AND EARLY TONIGHT TO S IL...AND ONLY BEGIN A NE MOVEMENT LATE TONIGHT. THIS WILL SPREAD STRONGER MID AND UPPER LEVEL FLOW INTO OUR AREA. TOOK A GANDER AT CRAS MODEL...GFS AND NAM PRECIP EFFICIENCY AND GFS...NAM AND RUC MODEL SOUNDINGS...AND AT THIS TIME ALL SIGNS POINT TO LIKELIHOOD THAT A WATCH WILL BE IN EFFECT AT LEAST IN OUR FAR W BY LATE THIS AFTERNOON. MESOSCALE MODEL REFLECTIVITIES ALSO SHOW GOOD DEVELOPMENT OF CONVECTION OVER OUR W AND NW BY LATE THIS AFTERNOON. STEEP LAPSE RATES BOTH 700 TO 500 MB AND 850 TO 500 MB...PLUS DECENT CAPE IN HAIL GROWTH ZONE SHOW LIKELIHOOD OF A LARGE HAIL AND DAMAGING WIND THREAT. LARGE HELICITY VALUES THANKS TO A VEERING LOW LEVEL WIND PROFILE ALSO MAKE TORNADOES A REAL POSSIBILITY...BUT MAINLY IN W PORTIONS OF THE AREA. TO SUMMARIZE...THERE WILL BE AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS...SOME SEVERE...IN THE W PART OF OUR CWA THIS AFTERNOON. OVER THE E PART OF OUR AREA...THERE WILL BE MUCH LESS MOISTURE AVAILABLE INITIALLY SO THAT ONLY LOWER CHANCES OF PRECIP CAN BE EXPECTED. WITH THE UPPER LOW TAKING A MORE NE MOVEMENT LATE TONIGHT...THE THREAT FOR SEVERE WEATHER WILL LESSEN AS WIND FIELDS BEGIN TO RELAX SOMEWHAT. WILL BEEF UP POPS A TAD TO LIKELY CATEGORY BY LATE THIS AFTERNOON IN FAR W AND NW...BUT NOT CHANGE THEM MUCH FOR REST OF AREA. && .PREV DISCUSSION... /ISSUED 534 AM CDT WED MAY 25 2011/ AVIATION 12Z DISCUSSION... STORM SYSTEM WILL MOVE EASTWARD AND OUT OF THE PLAINS STATES TODAY. THE ASSOCIATED FRONTAL BOUNDARY WILL REACH MIDDLE TN ON THURSDAY BUT PRE FRONTAL TROUGHING WILL BRING A ROUND OF STRONG TO SEVERE TSTMS AFT 00Z. HOWEVER...AS THE STORMS MOVE EAST TONIGHT THEY WILL WEAKEN WITH TIME. CIGS AND VSBYS WILL FALL WITHIN THE IFR CATEGORY WHEN THE HEAVIER CONVECTION TAKES PLACE. PREV DISCUSSION... /ISSUED 346 AM CDT WED MAY 25 2011/ DISCUSSION... ANALYSIS SHOWING WELL DEFINE WARM FRONT ACROSS THE OH VALLEY...WITH AIRMASS QUITE UNSTABLE SOUTH SIDE. ALOFT...WEAK ML/UL RIDGING OCCURRING ACROSS THE MID-SOUTH IN RESPONSE TO CLOSED LOW DROPPING INTO KS. REGIONAL RADARS QUIET COMPARING PREVIOUS FEW NIGHTS WITH WIDESPREAD PCPN IN VICINITY OF PLAINS FEATURES. PLAINS SFC/UPPER LOWS WILL MAKE SLOW TRACK EAST...MOVING OVER MO 00Z THU...IL 12Z...AND THEN UP TOWARD NORTHERN IN 00Z FRI. THIS WILL ULTIMATELY BRING UPPER TROUGH AND SFC FRONTAL BOUNDARY INTO THE REGION AND ACROSS THE CWA LATER THU. ASSOCIATED DEEP MOISTURE AND BETTER UVV WILL BEGIN TO AFFECT THE CWA LATER TODAY BUT MORE SO TONIGHT AND THU. THESE FEATURES WILL HAVE PLENTY OF WORK WITH AS CAPES RUN 2000-2500 AND SRH 250+...ESPECIALLY EARLY ON. THIS WILL BRING A ROUND OF STRONG/SEVERE THUNDERSTORMS TO THE AREA LARGELY TONIGHT/EARLY THU. THERMODYNAMIC PARAMETERS REALLY WEAKEN IN THE AFTERNOON AS WHAT LOOKS LIKE PRE-FRONTAL BOUNDARY PASSES. A FEW STORMS WILL HANG AROUND THU EVENING BUT THEY SHOULD BE PRETTY MUCH WRAPPED UP BY FRI MORNING WITH FRONT AND UPPER TROUGHS JUST EAST. WHILE FRI EXPECTED TO BE DRY...PASSING FRONT GONE RAPIDLY AS SOUTHERLY LL FLOWS RETURNS FRI NIGHT AND ANOTHER BOUNDARY SETS UP JUST NORTHWEST. ML/UL FLOW GOES BACK WEST AND POSSIBILITY OF ISO- SCT DEVELOPMENT OUT WEST RIDING DOWN INTO THE CWA LATE FRI NIGHT/EARLY SAT AGAIN ARISES. ANY CONVECTION EARLY SAT SHOULD BE IT FOR MOST FROM THAT POINT INTO MID-WEEK AS SFC HIGH AND UPPER RIDGE BECOMES DOMINANT SUN AND HOLDS INTO WED. SOME MOISTURE DOES SNEAK IN EARLY WED EAST AND THAT MAY POP A FEW ISO STORMS ON THE PLATEAU IN THE AFTERNOON. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ STEIGERWALDT  FXUS64 KOHX 190151 AAC AFDOHX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE NASHVILLE TN 851 PM CDT SAT JUN 18 2011 .UPDATE... 00Z SUN KOHX SOUNDING PROFILE CONTINUING TO SHOW OVERALL GOOD PRECIP WATER CONTENT AT 1.59 INCHES...ALONG WITH A VARIETY OF GOOD INSTABILITY INDICES'S INDICATORS....BUT GENERALLY DRY BELOW 600 MB. LOOKING AT CURRENT SATELLITE/SFC OBS...CLEARING SKIES W TO E ACROSS THE MID STATE...WITH SOME WEAK CONVECTION NOTED ACROSS MS RIVER VALLEY AND INTO ERN AR AND SRN MO. NWLY FLOW PATTERN IS EXPECTED TO CONTINUE ACROSS THE MID STATE THRU THE REMAINDER OF THE NIGHT TIME HRS ALSO...WITH BEST POSSIBLE STORM TRACK POTENTIAL ACROSS ERN PORTIONS OF THE MID STATE. HIGH RESOLUTION RAPID REFRESH MODEL BRINGING CURRENT ERN KS/WRN-CNTRL MO CONVECTION TO NEAR NW PORTIONS OF THE MID STAT BY 09Z...THEN MOVING CONVECTION EWD AND THEN SWD INTO THE CUMBERLAND PLATEAU REGION BY 12Z. CRAS FORECASTED SAT IMAGERY ALSO BRINGING INTO W PORTIONS OF THE AREA BY 12Z SUN AT LEAST A PLUME OF MOISTURE WHICH IS PRESENTLY ASSOCIATED WITH E TX/SE OK/W AR CONVECTION. EVEN THOUGH NO CONVECTION PRESENTLY ACROSS THE MID STATE... DAY ONE CONVECTIVE OUTLOOK POINTS TO THE FACT THAT A STRENGTHENING LOW LEVEL JET THAT PERSISTENCE OF SEVERAL QUASI-LINEAR CLUSTERS IS POSSIBLE THAT MIGHT MOVE INTO THE MID STATE OVERNIGHT. WITH ALL OF THIS IN MIND...WILL GO WITH MOCLR SKIES THRU THE REMAINDER OF THE EVENING HRS...WITH SKIES BECOMING MOCLDY AFTER MIDNIGHT...AND WILL CONTINUE WITH THE PREVIOUS UPDATE WORDING OF ISOLATED SHWRS/TSTMS EARLY...BECOMING LIKELY LATE. WILL ALSO ADDRESS WORDING FOR SUN TO REFLECT POSSIBLE MCS IMPACTS ACROSS THE MID STATE BY RAISING POPS AND ADDRESSING MOCLDY SKIES THRU THE REMAINDER OF THE MORNING HRS. && .PREV DISCUSSION.../ISSUED 632 PM CDT SAT JUN 18 2011/ UPDATE...FOR AVIATION. AVIATION...00Z TAFS. VFR CONDITIONS WITH LIGHT SSW WINDS EXPECTED THROUGH 06Z. ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP OVER AR/MO THIS EVENING...AND EVENTUALLY MOVE/SPREAD INTO PARTS OF THE TN VALLEY LATE TONIGHT INTO SUNDAY MORNING. BEST GUESS FOR TSRA IS FROM 09Z- 15Z AT BNA/CSV. AFTER THE MORNING STORMS MOVE AWAY...LOOK FOR SCT CUMULUS CLOUDS WITH GUSTY SW WINDS TO 25KT THROUGH THE AFTERNOON. 13 PREV DISCUSSION.../ISSUED 534 PM CDT SAT JUN 18 2011/ UPDATE... WILL MAKE SOME TWEAKS TO TONIGHT'S FORECAST WITHIN THE SUITE OF FORECAST PRODUCTS. SHORT RANGE MODELS...HIGH RESOLUTION RAPID REFRESH MODELS...SATELLITE/SFC OBS...ALL SUPPORTING A SCENARIO SIMILAR TO WHAT HAPPENED EARLY THIS MORNING WITH ANOTHER MCS DEVELOPING TO OUR NW AND MOVING INTO THE MID STATE LATE TONIGHT. THUS...HAVE DECREASED POPS ACROSS THE AREA INTO THE 20 PERCENT RANGE THRU THE EARLY MORNING HRS...WITH SHWRS/TSTMS BECOMING LIKELY LATE. HAVE ALSO MADE A MINOR TWEAK IN SKY CONDITIONS TO SUPPORT A GENERALLY MOCLDY SKY TREND. HAVE LOWERED OVERNIGHT LOWS BY A COUPLE OF DEGREES ACROSS THE ENTIRE AREA AS BREAKS IN CLOUDS SHOULD ALLOW FOR LOWS AROUND 70...MID 60S PLATEAU. WITH SLY/SWLY SFC PRESSURE GRADIENT EXPECTED TO REMAIN ACROSS THE MID STATE THRU THE NIGHTTIME HRS ALSO...INCREASED WINDS SPEEDS INTO THE 5 TO 15 MPH RANGE. 31 PREV DISCUSSION.../ISSUED 239 PM CDT SAT JUN 18 2011/ DISCUSSION...SOUTHERN MIDDLE TENNESSEE HAS BEEN THE FOCUS OF SEVERE STORMS THIS AFTERNOON AS A MESOSCALE SYSTEM HAS WORKED ITS WAY ACROSS THE REGION. SURFACE MAP AT 19Z SHOWS A MESO-HIGH OVER THE MID STATE OWING TO WIDESPREAD OUTFLOW, WITH THE UPPER FLOW LARGELY ZONAL. SPC HAS MIDDLE TENNESSEE UNDER A SLIGHT RISK OF SEVERE WEATHER TOMORROW AND TOMORROW NIGHT, AND MAY ONCE AGAIN HAVE TO DEAL WITH A MESOSCALE COMPLEX TOMORROW MORNING AS MODELS BRING A MOISTURE BULLS-EYE THROUGH THE MID STATE AROUND 12Z. GFS MODEL SOUNDING FOR BNA FOR 12Z SUNDAY LOOKS ALMOST IDENTICAL TO THIS MORNING'S OBSERVED SOUNDING, WITH A NEAR-SURFACE STABLE LAYER, DEEP MID-LEVEL INSTABILITY, AND MID-LEVEL DRY AIR INTRUSION. AFTERWARDS, LOOK FOR THE UPPER RIDGE TO BUILD ACROSS MIDDLE TENNESSEE AS THE ATMOSPHERE FINALLY DRIES OUT AND HOT WEATHER RETURNS. STILL EXPECTING A COLD FRONT AROUND MID WEEK THAT WILL BRING A PROLONGED CHANCE OF RAIN AND COOLER WEATHER LASTING INTO NEXT WEEKEND. ROSE && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31