000 FXUS64 KMEG 100546 AFDMEG AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MEMPHIS TN 1146 PM CST THU FEB 9 2012 .UPDATE... UPDATED TO ADD 06Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 856 PM CST THU FEB 9 2012/ UPDATE... LOW/MIDLEVEL STRATUS CLOUDS HAD FINALLY RETREATED TO NW TN AND MO BOOTHEEL AT MIDEVENING. A THIN VEIL OF CIRRUS WAS OVERSPREADING THE REMAINDER OF THE MIDSOUTH. LIGHT EAST WINDS AND DEWPOINTS IN THE 20S WAS RESULTING IN GOOD RADIATIONAL COOLING...CIRRUS NOTWITHSTANDING. FORECAST WAS RECENTLY UPDATED WITH ANOTHER DROP IN PROJECTED OVERNIGHT MIN TEMPS. PWB PREV DISCUSSION... /ISSUED 554 PM CST THU FEB 9 2012/ UPDATE... UPDATED TO ADD 00Z AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 343 PM CST THU FEB 9 2012/ DISCUSSION... A NORTHERN STREAM MID LEVEL SHORTWAVE CURRENTLY POSITIONED OVER THE WESTERN HIGH PLAINS WILL CONTINUE TO MOVE EAST AND ACROSS THE MID SOUTH ON FRIDAY. MOISTURE WILL ADVECT NORTHWARD FROM THE WESTERN GULF OF MEXICO BEGINNING THIS EVENING AND CONTINUING THROUGH FRIDAY AHEAD OF AN ARCTIC COLD FRONT. ISENTROPIC ASCENT SHOULD SUPPORT THE DEVELOPMENT OF WIDESPREAD LIGHT RAIN ON FRIDAY AHEAD OF THE FRONT. TEMPERATURES WILL REMAIN SLIGHTLY BELOW AVERAGE ON FRIDAY. THE ARCTIC COLD FRONT WILL SWEEP ACROSS THE MID SOUTH FRIDAY EVENING WITH MUCH COLDER TEMPERATURES MOVING INTO THE AREA UNDER GUSTY NORTHWEST WINDS. DRY WEATHER WILL RETURN FOR THE WEEKEND BUT TEMPERATURES WILL BE WELL BELOW NORMAL AS AN ARCTIC HIGH PRESSURE SETTLES OVERHEAD. THE ARCTIC FRONTAL BOUNDARY SHOULD PUSH WELL INTO THE NORTHERN GULF OF MEXICO. THE ARCTIC HIGH PRESSURE WILL SHIFT EASTWARD BY SUNDAY NIGHT AS A STRONGER SOUTHERN STREAM SHORTWAVE APPROACHES FROM THE WEST. THIS SHORTWAVE WILL ATTEMPT TO PHASE WITH A NORTHERN STREAM SHORTWAVE DROPPING SOUTH FROM THE UPPER MISSISSIPPI VALLEY ON MONDAY. AS THIS OCCURS...A LOW LEVEL FRONTAL BOUNDARY LIFTING NORTH FROM THE GULF OF MEXICO WITH BECOME BETTER DEFINED ACROSS THE NORTHERN GULF STATES AS WEAK SURFACE LOW PRESSURE DEVELOPS AND MOVES EAST ALONG THE FRONT. ABUNDANT MOISTURE WILL ADVECT NORTHWARD OVER THE FRONT INTO THE MID SOUTH ON MONDAY. THIS MOISTURE WILL OVERRUN THE RESIDUAL RETREATING ARCTIC AIRMASS IN PLACE. THIS SHOULD SUPPORT THE DEVELOPMENT OF PRECIPITATION OVER THE AREA. THERE WILL LIKELY BE A VARIETY OF PRECIPITATION TYPES ACROSS THE REGION MONDAY WITH THE POTENTIAL FOR SNOW...SLEET AND FREEZING RAIN ACROSS THE NORTH...A MIX OF SLEET...FREEZING RAIN...AND RAIN ALONG THE INTERSTATE 40 CORRIDOR...AND MAINLY RAIN SOUTH OF INTERSTATE 40 WITH THE ONSET OF PRECIPITATION. AS WARMER AIR SURGES NORTHWARD...THERE SHOULD BE A SLOW TRANSITION TO RAIN FROM SOUTH TO NORTH THROUGH MONDAY AFTERNOON AND MONDAY NIGHT. THERE IS SOME POTENTIAL FOR AN EXTENDED PERIOD OF WINTRY WEATHER ACROSS NORTHERN PORTIONS OF THE MID SOUTH. THERE IS STILL SOME UNCERTAINTY WITH RESPECT TO HOW FAR SOUTH AND HOW LONG THE COLD AIRMASS WILL REMAIN ENTRENCHED ACROSS THE AREA...SO ADJUSTMENTS IN PRECIP TYPES AND TEMPERATURES MAY BE NEEDED IN LATER FORECASTS. ALL PRECIPITATION SHOULD CHANGE TO ALL RAIN BY TUESDAY MORNING IN ALL AREAS AS A WARMER AIRMASS MOVES IN FROM THE SOUTH. IN ADDITION...PRECIPITATION SHOULD ALSO COME TO AN END BY TUESDAY AFTERNOON AS THE SHORTWAVE MOVES EAST. HIGH PRESSURE WILL BRIEFLY BUILD BACK OVER THE MID SOUTH FOR MID WEEK WITH A RETURN TO DRY AND WARMER CONDITIONS. ANOTHER SHORTWAVE WILL APPROACH THE MID SOUTH BY THE END OF NEXT WEEK BRINGING ADDITIONAL CHANCES FOR SHOWERS AND A FEW THUNDERSTORMS. MUCH WARMER WEATHER SHOULD RETURN FOR THE END OF THE EXTENDED FORECAST PERIOD. JLH && .AVIATION... 06Z TAF CYCLE A SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT WILL MOVE ACROSS THE LOWER MISSISSIPPI VALLEY ON FRIDAY. BASED ON LATEST SHORT TERM TRENDS...THINK RAIN WILL ARRIVE AROUND/OR AFTER DAYBREAK AT MEM/JBR AND SPREAD EAST TO MKL/TUP THROUGHOUT THE MORNING. RAIN WILL GRADUALLY COME TO AN END AT JBR BY LATE FRIDAY AFTERNOON/EARLY FRIDAY EVENING...THEN SPREADING ACROSS THE REMAINDER OF THE AREA THROUGH THE EVENING. VFR CONDITIONS WILL PERSIST THROUGH AT LEAST 10/12Z. A GRADUAL DETERIORATION TO MVFR CONDITIONS ANTICIPATED AT TAF SITES FRIDAY MORNING INTO FRIDAY AFTERNOON. CEILINGS MAY DETERIORATE TEMPORARILY TO IFR CONDITIONS BETWEEN 10/17-21Z AT JBR. LIGHT SOUTHEAST WINDS WILL GRADUALLY VEER SOUTHWEST TO WEST BETWEEN 5-7 KTS AS THE COLD FRONT MOVES THROUGH AND NORTHWEST BETWEEN 9-11 KTS AFTER FRONTAL PASSAGE. && .PRELIMINARY POINT TEMPS/POPS... MEM 33 48 28 34 / 10 70 20 0 MKL 26 49 26 33 / 0 60 30 0 JBR 31 46 24 32 / 10 70 10 0 TUP 30 51 31 38 / 0 50 40 0 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$