River Flood Advisory 10, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
618 PM CST MON FEB 28 2011

.UPDATE...
WIND ADVISORY HAS EXPIRED. CURRENT SPEEDS ARE GENERALLY IN THE 10
TO 20 MPH RANGE ACROSS THE MID STATE. MODELS IN AGREEMENT WITH A
CONTINUATION OF THE WIND MAG WEAKENING TREND AS THE GRADIENT
SLOWLY RELAXES OVERNIGHT.

CURRENT GRIDS SHOW A CONTINUATION OF A SLIGHT CHANCE OF SHOWERS
FOR THE PLATEAU UNTIL 03Z. I WILL...HOWEVER...GO AHEAD AND PULL
THE PLUG ON THAT AND REMOVE THE POPS NOW.

OTW...LOW TEMPS DOWN INTO THE LOWER TO MID 30S APPEARS TO BE IN
GOOD SHAPE. LOW CLOUDINESS STILL COVERS MOST OF THE AREA BUT WE
ARE SEEING SOME CLEARING ACROSS THE FAR NORTHWEST. MODELS LEAN
TOWARD A SLOW CLEARING TREND WITH MOSTLY CLOUDY SKIES PREVAILING
THROUGH AT LEAST 10Z OR SO. CURRENT SKY GRIDS APPEAR TO BE A TOUGH
TOO BULLISH WITH THE CLEARING TREND. THUS...I WILL BACK THE
CLEARING TREND UP BY A FEW HOURS.

ZONES WILL SOON BE OUT AFTER GRID UPDATE.

&&

.PREV DISCUSSION... /ISSUED 556 PM CST MON FEB 28 2011/

UPDATE...FOR 00Z TAFS.

AVIATION...
COLD FRONT AND ASSOCIATED WIDESPREAD PCPN FROM EARLIER NOW WELL
EAST AND IS EXPECTED TO MOVE FURTHER OUT OF THE PICTURE TONIGHT.
LOW-LEVEL MOISTURE HOWEVER WILL LINGER BEHIND...AND THUS MVFR/IFR
CEILINGS...AND VSBYS CSV EARLY THIS EVENING...WILL CONTINUE WELL
INTO THE NIGHT. WHILE CONDITIONS MAY IMPROVE OVERNIGHT...THIS
MOST LIKELY WILL OCCUR AFTER 12Z TUE.

PREV DISCUSSION... /ISSUED 259 PM CST MON FEB 28 2011/

SHORT TERM...SURFACE COLD FRONT HAS NOW SWEPT ACROSS OUR AREA AND
THE ATMOSPHERE IS RAPIDLY STABILIZING FROM THE NORTHWEST AS MUCH COOLER
AIR MOVES IN ON NORTHWESTERLY WINDS. RADAR SHOWS SOME LIGHT
SHOWERS STILL HANGING IN AT SOME PLACES BEHIND THE FRONT AND WILL
PROBABLY KEEP A 40-60% POP RUNNING THROUGH 00Z, THEN KEEP ONLY A
20% CHANCE ALONG THE CUMBERLAND PLATEAU FOR THIS EVENING (00Z-03Z).

WILL CANCEL FFA AT 3PM, PRIOR TO ZONE ISSUANCE, SINCE ALL HEAVY
RAINFALL HAS NOW PUSHED EAST OF THE MID STATE. HOWEVER, WILL LET WIND
ADVISORY REMAIN OVER OUR EASTERN AND SOUTHERN AREAS THROUGH 6 PM,
AS WINDS REMAIN A BIT GUSTY IN A FAIRLY BROAD ZONE IMMEDIATELY
BEHIND THE SURFACE FRONT.

FOLLOWING PASSAGE OF THE COLD FRONT, EXPECT DRY CONDITIONS TO
GRACE THE MID STATE THROUGH THURSDAY NIGHT, AS HIGH PRESSURE
BUILDS ACROSS THE AREA. A DRY COLD FRONT SWEEPS THROUGH WEDNESDAY
AFTERNOON AND NIGHT, REINFORCING NORTHERLY FLOW ACROSS THE
TENNESSEE VALLEY.

SOUTHERLY FLOW FINALLY BECOMES RE-ESTABLISHED THURSDAY NIGHT, AND
EXPECT SOME ISENTROPIC CLOUDS TO SPREAD IN BY SUNRISE FRIDAY. AM
NOT TOO SURE OF HOW MUCH SUNSHINE WILL DEVELOP DURING THE DAYLIGHT
HOURS ON FRIDAY AND AM HESITANT TO GO TOO MUCH ABOVE GFS MOS
GUIDANCE FOR THAT PARTICULAR PERIOD.

LONG TERM...STILL LOOKS LIKE ANOTHER COLD FRONT PUSHES INTO THE
AREA SATURDAY AND SATURDAY NIGHT AND HAVE GONE WITH SOMEWHAT OF A
GFS/ECMWF COMPROMISE ON THE FRONTAL MOVEMENT AND PRECIP PATTERN. LOOKS
LIKE THIS FRONT COULD BE SIMILAR TO THE LAST FEW, WITH SOME HEAVY
DOWNPOURS AND POSSIBILITY FOR ISOLATED SEVERE THUNDERSTORMS.

THE CHANGE TO A POSITIVE ARCTIC OSCILLATION OVER RECENT WEEKS HAS
DEFINITELY PUT US IN A MORE SPRING-LIKE PATTERN, WITH A
SIGNIFICANT INCREASE IN PRECIPITATION AND WARMTH. EXTENDED PROGS
SHOW LITTLE, IF ANY, CHANGE IN THE PREVAILING WEATHER PATTERNS
THROUGH MID-MARCH. SO, IF WE KEEP OUR FINGERS CROSSED, WE MAY FIND
THAT OURS DAYS IN THE DEEP FREEZE, THAT WE ENDURED DURING THE
FIRST TWO-THIRDS OF THE WINTER, MAY INDEED BE OVER. IN ITS PLACE,
WE MAY OURSELVES IN SOGGY BOTTOM.

&&

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

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
153 PM CST MON FEB 28 2011

TNZ005>011-022>034-056>066-075-077>080-093>095-011200-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-
SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS-
WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DE KALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
153 PM CST MON FEB 28 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...THIS AFTERNOON AND TONIGHT...

THUNDERSTORMS WITH HEAVY RAINFALL HAVE TAPERED OFF...BUT WATER
LEVELS WILL REMAIN ON SOME CREEKS AND SMALL STREAMS IN THE AREA
THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTERS AND LOCAL EMERGENCY MANAGEMENT OFFICIALS ARE ENCOURAGED
TO REPORT HEAVY RAINFALL AMOUNTS OR FLOODING TO THE NATIONAL
WEATHER SERVICE IN NASHVILLE.

13