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AREA FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE RALEIGH NC 
730 PM EDT SAT JUL 4 2015

.SYNOPSIS... 
A SERIES OF DISTURBANCES ALOFT WILL MOVE OVERHEAD AND INTERACT WITH 
A SURFACE FRONT THAT WILL WAVER ACROSS VA AND NC THROUGH MONDAY. 

&&

.NEAR TERM /THROUGH TONIGHT/... 
AS OF 310 PM SATURDAY...

THROUGH THE LATE AFTERNOON AND EVENING HOURS...SCATTERED CONVECTION 
WILL LIKELY BE FOCUSED ON TWO UPPER LEVEL SHEAR AXES...ONE ACROSS 
THE FAR SOUTHERN COUNTIES...AND THE OTHER NEAR THE NW PIEDMONT. IN 
BETWEEN...A MARGINALLY UNSTABLE AIR MASS MAY SUPPORT ISOLATED 
CONVECTION THROUGH SUNSET. THE CONVECTION ACROSS THE NW PIEDMONT MAY 
PERSIST PAST SUNSET AS A SLOW MOVING SFC BOUNDARY INTERACTING WITH 
THE AVAILABLE MOISTURE AND INSTABILITY SHOULD SUSTAIN UPDRAFTS. 

BETTER DCAPE AND INVERTED V SIGNATURE ON FORECAST SOUNDINGS ACROSS 
THE SOUTH SUGGEST A POTENTIAL FOR ISOLATED STRONG-SEVERE STORMS WITH 
THE PRIMARY HAZARDS OF STRONG/DAMAGING WINDS AND MARBLE TO QUARTER 
SIZE HAIL...ESPECIALLY OVER PARTS OF THE SANDHILLS AND SOUTHERN 
COASTAL PLAIN.

BULK OF CONVECTION SHOULD DIMINISH BY MIDNIGHT WITH A FEW STRAY 
SHOWERS PERSISTING INTO THE OVERNIGHT HOURS. NO CHANGE IN OVERNIGHT 
TEMPS...UPPER 60S-LOWER 70S.

&&

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/... 
AS OF 310 PM SATURDAY...

MID-UPPER LEVEL TROUGH OVER THE TN VALLEY AMPLIFIES...CAUSING 
HEIGHTS OVER OUR REGION TO SLOWLY BUILD/EXPAND NORTHWARD. THIS WEAK 
SUBSIDENCE MAY INITIALLY INHIBIT CONVECTIVE DEVELOPMENT...ESPECIALLY 
ACROSS OUR SE COUNTIES. PERTURBATIONS ALOFT CROSSING WESTERN NC INTO 
WESTERN VA WILL AID TO FOCUS LOW LEVEL CONVERGENCE OVER THE NW 
PIEDMONT...LEADING TO SCATTERED CONVECTION BY AFTERNOON-EARLY 
EVENING. SINCE MAJORITY OF MODEL GUIDANCE HAS BACKED OFF ON UPPER 
SUPPORT...HAVE LIMITED POPS TO SOLID CHANCE ACROSS THE NW...TRENDING 
TO SMALL CHANCE ACROSS THE SE. 

MAX TEMPS SUNDAY AFTERNOON WILL FOLLOW SIMILAR TREND WITH MID 80S NW 
DUE TO MIXTURE OF SUN/CLOUDS TO AROUND 90 SE.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/... 
AS OF 240 PM SUNDAY...

A WEAKENING MID LEVEL LOW INVOF THE SOUTHERN TO CENTRAL APPALACHIANS 
MONDAY MORNING IS EXPECTED TO LIFT NORTHWARD AND WEAKEN MONDAY NIGHT 
INTO TUESDAY. THE TRAILING ASSOCIATED WEAK S/W TROUGH IS EXPECTED TO 
MOVE ACROSS CENTRAL NC ON MONDAY INTO MONDAY NIGHT. THUS... EXPECT 
WE COULD SEE SOME SCATTERED SHOWERS AND STORMS MONDAY AFTERNOON INTO 
THE EVENING AGAIN... WITH THE HIGHEST PROBABILITY ACROSS THE NORTH 
AND EASTERN PORTIONS OF CENTRAL NC.

THE SUB-TROPICAL RIDGE IS THEN FORECAST TO ATTEMPT TO BUILD BACK 
OVER THE SOUTHEASTERN U.S. HOWEVER... AS A SERIES OF NORTHERN STREAM 
DISTURBANCES TRACK ACROSS THE NORTHERN TIER OF THE COUNTRY THE MID 
LEVEL RIDGE WILL HAVE A HARD TIME FULLY EXERTING ITS DOMINATES ON 
CENTRAL NC... WITH ANY ASSOCIATED SURFACE FRONT GENERALLY REMAINING 
TO THE NORTH OF CENTRAL NC INTO AT LEAST LATE WEEK. HOWEVER... AS 
ANY SUBSTANTIAL DISTURBANCES AND ASSOCIATED FRONTS PASS TO THE NORTH 
OF CENTRAL NC... EXPECT WE SHOULD STILL SEE A SHARPENING OF THE 
PIEDMONT TROUGH OVER CENTRAL NC DURING THIS THE MEDIUM RANGE... 
HELPING TO YIELD ISOLATED TO WIDELY SCATTERED SHOWERS AND STORMS 
EACH AFTERNOON AND EVENING.

HIGH TEMPS DURING THE PERIOD WILL START OFF SLIGHTLY BELOW NORMAL... 
GENERALLY IN THE MID TO UPPER 80S ON MONDAY... WITH HIGHS REBOUNDING 
TO AROUND NORMAL FOR THE REST OF THE PERIOD (UPPER 80S TO LOWER 90S. 
LOW TEMPS ARE EXPECTED TO BE IN THE UPPER 60S TO LOWER 70S... WITH 
POSSIBLY A FEW MID 70S BY LATE WEEK INTO NEXT WEEKEND.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/... 
AS OF 730 PM SATURDAY...

24 HOUR TAF PERIOD: SHOWER IN THE VICINITY OF KRWI WILL MOVE THROUGH 
QUICKLY...OTHERWISE TAF SITES STAYING IN THE DRY WEATHER SO FAR. 
STILL SOME GUSTS OUT THERE THIS AFTERNOON UP TO 20 KTS OR SO OUT OF 
THE SOUTHWEST. THESE ARE EXPECTED TO DIE DOWN AFTER DARK. ISOLATED 
TO SCATTERED CONVECTION STILL POSSIBLE THROUGH THE EVENING HOURS BUT 
COVERAGE IS LIGHT ENOUGH TO KEEP IT OUT OF THE TAFS AT THIS TIME. 
SCATTERED SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE ON SUNDAY 
AFTERNOON...INCREASING IN COVERAGE NEAR THE END OF THE TAF PERIOD. 
MODELS DO NOT INDICATE MUCH IN THE WAY OF FOG OR LOW STRATUS BUT 
TERMINALS RECEIVING RAIN COULD SEE SOME BRIEF DROP IN CONDITIONS 
DURING THE OVERNIGHT HOURS.

LONG TERM: LONG TERM MODELS SHOW THE UNSETTLED PATTERN HOLDING OVER 
CENTRAL NC...INDICATING A CHANCE FOR SHOWERS AND THUNDERSTORMS AS 
WELL AS ADVERSE AVIATION CONDITIONS AT LEAST THROUGH MIDWEEK.

&&
 
..RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...26
NEAR TERM...WSS
SHORT TERM...WSS 
LONG TERM...BSD
AVIATION..ELLIS

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