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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
1009 AM CST SAT FEB 28 2015

.DISCUSSION...WATER VAPOR SATELLITE/WSR-88D VAD WIND PROFILES
INDICATE A COUPLE OF VERY SUBTLE SHORTWAVES EMBEDDED WITHIN ZONAL
TO SLIGHTLY SOUTHWEST FLOW ALOFT ACROSS THE LOWER MISSISSIPPI
VALLEY. THIS UPPER LEVEL SHORTWAVE AND WEAK ISENTROPIC ASCENT HAS
PRODUCED SOME LIGHT SNOW ACROSS PORTIONS OF NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL AND FAR NORTHWEST TENNESSEE THIS
MORNING. AREA ASOS/AWOS OBSERVATIONS HAVE NOT INDICATED ANY
PRECIPITATION FALLING FROM THIS ACTIVITY EVEN THOUGH SOME REPORTS
HAVE COME IN THIS MORNING OF SNOWFALL AMOUNTS AROUND AN INCH.
BASED ON THE SNOWFALL REPORTS AND A POTENTIAL FOR THE SHORTWAVE TO
STILL IMPACT THE ABOVE MENTIONED AREA FOR THE NEXT HOUR OR
TWO...DECIDED TO ISSUE A WINTER WEATHER ADVISORY UNTIL NOON. ANY
ADDITIONAL SNOW AMOUNTS ARE EXPECTED TO BE LIGHT. MAINLY FLURRIES
ARE POSSIBLE SOUTH OF THIS AREA. WILL MAKE ADJUSTMENTS AS
NECESSARY TO FORECAST TO REFLECT CURRENT TRENDS.

UPDATED GRIDS WILL BE AVAILABLE SHORTLY.

CJC

&&

.PREV DISCUSSION... /ISSUED 527 AM CST SAT FEB 28 2015/ 

DISCUSSION...
UPDATED FOR AVIATION DISCUSSION CORRECTION.

PREV DISCUSSION... /ISSUED 524 AM CST SAT FEB 28 2015/ 

DISCUSSION...
UPDATED FOR 12Z AVIATION DISCUSSION.

PREV DISCUSSION... /ISSUED 400 AM CST SAT FEB 28 2015/ 

DISCUSSION...

CURRENTLY...A WEAK UPPER LEVEL DISTURBANCE MOVING ACROSS THE
MIDSOUTH WITH LOTS OF MIDDLE AND HIGH CLOUDS. GOOD DEAL OF VIRGA
APPARENT ALL NIGHT ON KNQA WITH SOME FLAKES REACHING THE GROUND
ACROSS NE AR. ARCTIC SURFACE HIGH PRESSURE SITS OVER THE MID
ATLANTIC. TEMPS RANGE FROM THE UPPER TEENS AT PARIS TO LOWER 30S
ACROSS PARTS OF NE MS. 

TODAY...WSW ZONAL FLOW ACROSS THE MIDSOUTH WITH WEAK OVERRUNNING
MAINLY TO THE NW OF THE FORECAST AREA. A WEAK INVERTED SFC TROUGH
STARTS TO DEVELOP LATER IN THE DAY FROM THE LOWER MS VALLEY
THROUGH THE MIDSOUTH. EXPECT PLENTY OF CLOUDS WITH THE BEST
CHANCE OF SUN ACROSS N MS. COULD CONTINUE TO SEE A FEW FLAKES FLY
OVER NE AR WHICH IS ON THE EDGE OF THAT WEAK OVERRUNNING THROUGHOUT
THE DAY. AS THE ARCTIC HIGH PRESSURE SYSTEM LOOSES ITS GRIP
EXPECT A WARMER DAY WITH HIGHS FROM THE MID 30S ACROSS PARTS OF NE
AR TO AROUND 50 IN NE MS.

TONIGHT...WEAK OVERRUNNING IN WSW FLOW ALOFT WILL CONTINUE MAINLY
TO THE NW OF THE MIDSOUTH THOUGH SOME WEAK LIFT IS INDICATED
ACROSS NE AR AND THE MO BOOTHEEL. THESE AREAS COULD SEE SOME LIGHT
PRECIP OVERNIGHT INCLUDING THE CHANCE FOR FREEZING RAIN AS WARMER
AIR MOVES IN ALOFT. WILL MENTION THIS POSSIBILITY IN THE HWO.
WILL NEED TO WATCH THIS. LOWS WILL BE MILDER...IN THE 30S.

SUNDAY INTO MONDAY...A DECENT MID LEVEL SHORTWAVE PUSHING THROUGH
THE GREAT LAKES WILL PUSH A WEAK COLD FRONT THROUGH THE REGION
SUNDAY AND SUNDAY NIGHT WITH HEALTHY CHANCES FOR RAIN. HIGHS WILL
TOP 50 ACROSS A GOOD DEAL OF THE AREA AHEAD OF THIS WEAK FRONT ON
SUNDAY...THOUGH NE AR WILL BE STUCK IN THE 40S. SLIGHTLY COOLER
FOR MONDAY AS PRECIP CHANCES TAPER OFF FROM THE NORTH DUE TO
SURFACE HIGH PRESSURE BUILDING IN. THERE IS SOME CHANCE THAT
PRECIP COULD END AS SOME FREEZING RAIN ACROSS THE VERY NORTH LATE
SUNDAY NIGHT INTO EARLY MONDAY BUT THIS DOES NOT LOOK SIGNIFICANT.

MONDAY NIGHT INTO TUESDAY...WARM FRONT WILL LIFT THROUGH THE AREA
WITH GOOD CHANCE FOR RAIN AND A FEW THUNDERSTORMS. MUCH WARMER
TEMPS EXPECTED WITH HIGHS ON TUESDAY WELL INTO THE 60S...MAYBE
EVEN 70 IN SOME LOCATIONS. 

TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THIS PERIOD IS LOOKING
VERY INTERESTING. A COLD FRONT WILL PUSH THROUGH THE REGION AS
AHEAD OF A BROAD UPPER TROF PUSHING INTO THE CENTRAL U.S. CONCERN
IS SHIFTING FROM POTENTIAL SEVERE WEATHER TO WINTER WEATHER.
EXPECT THE FRONT TO PUSH SOUTH ACROSS THE AREA LATER TUESDAY NIGHT
INTO WEDNESDAY WITH SHOWERS AND THUNDERSTORMS ALONG AND AHEAD OF
THE FRONT. SEVERE PARAMETERS ARE NOT GREAT WITH MARGINAL
INSTABILITY. HEAVY RAINFALL COULD BE AN ISSUE. AFTER THE FRONTAL
PASSAGE A VERY COLD AIRMASS MOVES IN WITH FALLING TEMPS ON
WEDNESDAY. MEANWHILE POST FRONTAL OVERRUNNING CONTINUES FOR
PERHAPS MORE THAN 12 HOURS AFTER FRONTAL PASSAGE. 00Z GFS AND
ECMWF BOTH SHOW THIS SCENARIO SO THERE IS SOME CONFIDENCE IN THE
POTENTIAL FOR WINTER WEATHER. WENT WITH THE SLOWER ECMWF SOLUTION
WHICH MAKES SENSE BECAUSE THE FRONT BECOMES PARALLEL TO THE UPPER
FLOW. MODEL SOUNDINGS INDICATE THAT A TRANSITION FROM RAIN TO
FREEZING RAIN TO SLEET AND PERHAPS ENDING AS SNOW AS THE FRONT
PUSHES SE ACROSS THE REGION. PRECIPITATION WILL TAPER OFF
WEDNESDAY NIGHT WITH LOWS DIPPING INTO THE TEENS AND 20S.

THURSDAY AND FRIDAY...DRY AND BELOW NORMAL. 

SJM

&&

.AVIATION...
12Z TAFS

VFR WILL PREVAIL THROUGH MOST OF THE PERIOD HOWEVER MVFR...AND
POSSIBLY SOME IFR CIGS AT TUP...WILL MOVE INTO THE SITES LATE. IN
ADDITION LIGHT PRECIPITATION WILL SPREAD OVER THE REGION TONIGHT
WITH JBR HAVING THE GREATEST POTENTIAL FOR IMPACT. THERE IS ALSO A
SMALL POSSIBILITY OF FREEZING RAIN AT JBR AS TEMPERATURES WILL
FLIRT AT OR JUST ABOVE 32F. NORTHEAST TO EAST WINDS WILL EITHER
VEER SOUTHEASTERLY OR BECOME LIGHT AND VARIABLE. LOW LEVEL WIND
SHEAR CONDITIONS EXPECTED TO REDEVELOP AT MEM AND JBR BY EVENING.

JAB

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR CLAY-CRAIGHEAD-
     GREENE-LAWRENCE-MISSISSIPPI-RANDOLPH.

MO...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR DUNKLIN-
     PEMISCOT.

MS...NONE.
TN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR DYER-LAKE-OBION.

&&

$$

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