Severe Thunderstorm Warning 185, NWS Raleigh, NC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
345 PM EDT TUE JUL 10 2007

.SYNOPSIS...A TROUGH OF LOW PRESSURE WILL LINGER OVER CENTRAL NORTH
CAROLINA TONIGHT THROUGH WEDNESDAY. A COLD FRONT WILL MOVE SOUTHEAST
THROUGH THE AREA LATE WEDNESDAY THROUGH WEDNESDAY NIGHT... THEN
STALL OVER EASTERN NORTH CAROLINA THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...

WIDESPREAD STORMS ARE ONGOING ALONG THE WEAK MID LEVEL SHEAR AXIS &
925 MB TROUGH/MOISTURE AXIS AND BENEATH AN AREA OF UPPER DIVERGENCE
ASSOCIATED WITH A SPEED MAX OVER DELMARVA/NJ. ATMOSPHERE IS
MODERATELY TO HIGHLY UNSTABLE HERE WITH OBSERVED MUCAPES OF
2500-3000 J/KG. DESPITE THE WEAK SHEAR... THE STRONG INSTABILITY
WILL CONTINUE TO POSE A THREAT FOR DOWNBURST WINDS AND POSSIBLY HAIL
ESPECIALLY OVER THE NORTHERN HALF OF THE CWA UNTIL AROUND SUNSET.
THE MID LEVEL SHEAR AXIS IS EXPECTED TO SHIFT TO THE NORTHEAST
TONIGHT WITH A PERIOD OF ANTICYCLONIC FLOW IN ITS WAKE. ANOTHER WEAK
WAVE IS NOTED ON WATER VAPOR IMAGERY STRETCHING FROM ERN KY THROUGH
WRN NC INTO GA AND THIS SHOULD BRING ADDITIONAL DEBRIS CLOUD COVER
OVERHEAD OVERNIGHT... ALTHOUGH THIS SHOULD DAMPEN IN RESPONSE TO THE
VIGOROUS EASTWARD-MOVING VORTICITY MAXIMUM NOW ENTERING ARKANSAS.
WILL HAVE HIGH CHANCE POPS EARLY EVENING ACROSS THE NORTH...
TAPERING OFF SHORTLY AFTER MIDNIGHT AS 850 MB FLOW GOES UNIFORM
WESTERLY AND INCREASES. LOWS 71-74. -GIH

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...

RAIN CHANCES ARE LOOKING BETTER FOR WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT AS THE VORTICITY MAXIMUM SWINGS EAST THROUGH NC.
MORNING SUNSHINE WEDNESDAY SHOULD ALLOW FOR GOOD DESTABILIZATION ON
WHICH THE BROAD-SCALE PVA CAN WORK. MARGINAL MID LEVEL LAPSE RATES
INFERRED BY THE WARMER AIR UPSTREAM NOTED ON THIS MORNINGS 500 MB
UA ANALYSIS MAY LIMIT THE SEVERE THREAT... HOWEVER THE DEEP LAYER
SHEAR WILL BE IMPROVING. HAVE RAISED POPS TO LIKELY IN THE WESTERN
CWA AFTER 18Z... WITH LIKELY POPS THEN SWEEPING EAST ACROSS THE REST
OF THE CWA WEDNESDAY NIGHT. PRECIP AMOUNTS ARE DIFFICULT TO PIN
DOWN... WITH A NOTABLE WESTERLY COMPONENT IN THE LOW LEVELS
BALANCING PRECIPITABLE WATER VALUES THAT WILL BE WELL ABOVE
NORMAL... BETTER THAN 2.2 INCHES. CURRENT FORECAST HAS A HALF TO TWO
THIRDS OF AN INCH... BUT THIS COULD EASILY BE LOCALLY HEAVIER. HIGHS
89-95 WEDNESDAY AND LOWS 70-75 WEDNESDAY NIGHT. THE MODELS ARE
ENTHUSIASTIC ABOUT DRYING US OUT FROM WEST TO EAST EARLY THURSDAY AS
THE COLD FRONT PUSHES SOUTHEAST THROUGH THE AREA... AND WITH
IRREFUTABLE SUPPORTING EVIDENCE HAVE LOWERED OR DROPPED POPS
THURSDAY WITH FORECAST SOUNDINGS NOTING GOOD DRYING THROUGH THE
COLUMN AND SUBSIDENCE WARMING ALOFT. HIGHS 89-92. HAVE HELD ONTO
SMALL POPS IN THE EAST THROUGH THURSDAY NIGHT NEAR THE STALLED
FRONT... ALTHOUGH THIS FRONT DOES QUICKLY WASH OUT BY FRIDAY... AND
AN ISOLATED STORM COULD OCCUR OVER THE ENTIRE CWA FRIDAY AFTERNOON
WITH DESTABILIZATION RETURNING ACCORDING TO FORECAST SOUNDINGS. LOWS
65-71 AND HIGHS 88-92 FRIDAY. -GIH

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

LARGE SCALE FLOW PATTERN ACROSS NORTH AMERICAN SHOWS A DEVELOPING
POSITIVE PNA THROUGH THE MEDIUM RANGE... WHICH TYPICALLY EQUATES TO
BELOW NORMAL TEMPERATURES OVER THE MIDATLANTIC AND SOUTHEAST. THE
LATEST ECMWF (PREFERRED OVER THE GFS) SHOWS THE FRONT STALLING OVER
CENTRAL OR EASTERN NC FRIDAY NIGHT/SATURDAY... ALTHOUGH ITS
DIFFICULT TO TELL IF THIS IS THE ACTUAL COLD FRONT... BRINGING
LESS MOIST AND MORE STABLE AIR INTO THE NORTHWEST PORTION OF THE RAH
CWA... OR IF THIS IS MERELY THE PIEDMONT TROUGH WITH THE ACTUAL
FRONT STILL HOLDING JUST NW OF THE CWA... UNABLE TO GET SUFFICIENT
MOMENTUM TO GET IT OVER THE HIGHER TERRAIN OF VA/NC. THE ECMWFS 850
TROUGH ON FRIDAY GETS QUICKLY WASHED OUT BY LATE SATURDAY...
IMPLYING LITTLE OPPORTUNITY FOR TRULY DRY AIR TO WORK INTO THE CWA.
BASED ON THE HISTORIC LOW OCCURRENCE OF A GENUINE COLD FRONTAL
PASSAGE THROUGH CENTRAL NC... AM INCLINED TO FAVOR THE LATTER
SOLUTION OF THE FRONT HANGING UP JUST NW OF CENTRAL NC BEFORE
WASHING OUT OVER THE WEEKEND AS BERMUDA RIDGING ONCE AGAIN BUILDS
WESTWARD INTO THE SOUTHEAST STATES. FOR FRIDAY NIGHT/SATURDAY...
HAVE RETAINED POPS... LOWER WEST AND HIGHER EAST... AND LOWER AT
NIGHT THAN DURING THE DAYTIME. LOWS 69-73 AND HIGHS 88-91 WITH
ABUNDANT CLOUD COVER ESPECIALLY IN THE EAST. HAVE CARRIED ISOLATED
POPS SATURDAY NIGHT WITH PERSISTENT MOISTURE IN PLACE BUT WITH
SLIGHTLY DIFFLUENT 850 MB FLOW. THE ECMWF AND GFS BRING A WARM
FRONTAL FEATURE BACK NORTH THROUGH NC LATE SUNDAY... AND WITH
INCREASING 850 MB WINDS FROM THE SSW AND ADDITIONAL FORCING FROM THE
RIGHT ENTRANCE REGION OF THE SOUTHWESTERLY UPPER JET TO OUR NORTH...
HAVE GONE WITH 30-40% POPS MAINLY IN THE AFTERNOON/EVENING. 850 MB
FLOW REMAINS AOA 20 KTS THROUGH MONDAY WITH WEAK LEE TROUGHING AT
THE SURFACE AND THE POTENTIAL FOR MINOR MID LEVEL PERTURBATIONS TO
RIDE NORTHEASTWARD THROUGH CENTRAL NC... SO SIMILAR MID-RANGE CHANCE
POPS ARE PROJECTED FOR MONDAY AS WELL. BY TUESDAY... THE BERMUDA
RIDGE SHOULD CONTINUE TO STRENGTHEN OVER THE SOUTHEAST STATES AND
WITH THE UPPER JET CORE LIFTING OUT TO THE NORTHEAST AND
WEAKENING... HAVE GONE WITH LOWER SLIGHT-CHANCE POPS. TEMPERATURES
SUNDAY THROUGH TUESDAY WILL START OUT SLIGHTLY BELOW NORMAL WITH
HIGHS 85-88 SUNDAY... THEN TRANSITION TO NEAR TO ABOVE NORMAL
READINGS WITH HIGHS TUESDAY 88-92. -GIH

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...

THE COMBINATION OF A MOISTURE LADEN ATMOSPHERE AND A LEE SIDE TROUGH
WILL SERVE AS THE FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS
THROUGH THE EVENING HOURS. THERE IS A CHANCE OF MVFR VSBYS IN FOG
MAINLY EASTERN PORTION OF TAF AREA 09-12Z WEDNESDAY.

A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS IS POSSIBLE LATE
WEDNESDAY INTO THURSDAY AS AN UPPER LEVEL TROUGH BUILDS INTO THE
EASTERN U.S. AND SENDS A STRONGER COLD FRONT INTO NORTH CAROLINA.
THE FRONT WILL LINGER ALONG THE EASTERN PORTION OF THE TAF AREA
FRIDAY. -RHJ

&&

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

&&

SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...RHJ

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RALEIGH NC
421 AM EDT TUE JUL 10 2007

NCZ007>011-021>028-038>043-073>078-083>086-088-089-110830-
PERSON-GRANVILLE-VANCE-WARREN-HALIFAX-FORSYTH-GUILFORD-ALAMANCE-
ORANGE-DURHAM-FRANKLIN-NASH-EDGECOMBE-DAVIDSON-RANDOLPH-CHATHAM-WAKE-
JOHNSTON-WILSON-STANLY-MONTGOMERY-MOORE-LEE-HARNETT-WAYNE-ANSON-
RICHMOND-SCOTLAND-HOKE-CUMBERLAND-SAMPSON-
421 AM EDT TUE JUL 10 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED OVER CENTRAL
NORTH CAROLINA THIS AFTERNOON AND EVENING. THERE IS THE POTENTIAL
THAT AN ISOLATED STORM OR TWO COULD APPROACH OR BECOME SEVERE.

ANOTHER HOT AND HUMID DAY IS EXPECTED ACROSS CENTRAL NORTH
CAROLINA. HIGHS WILL BE IN THE MID 90S WITH HIGH HUMIDITIES. THIS MAY
RESULT IN HEAT INDEX VALUES AROUND 100 FOR A COUPLE OF HOURS THIS
AFTERNOON.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. HOWEVER THERE WILL
BE THE CONTINUED THREAT OF MAINLY AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

RA

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
423 PM EDT TUE JUL 10 2007

NCZ042-102130-
JOHNSTON-
423 PM EDT TUE JUL 10 2007

...STRONG THUNDERSTORMS WILL MOVE ACROSS JOHNSTON COUNTY THROUGH 530
PM EDT...

AT 423 PM EDT...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS OVER
COATS CROSSROADS...OR ABOUT 13 MILES WEST OF SMITHFIELD...MOVING EAST
AT 20 MPH.

SOME LOCATIONS AFFECTED BY THESE STORMS INCLUDE...COATS CROSSROADS
AND SMITHFIELD.

GUSTY WINDS OF 40 TO 50 MPH...VERY HEAVY RAIN AND  DANGEROUS
CLOUD-TO-GROUND LIGHTNING CAN BE EXPECTED WITH THESE STORMS. THESE
WINDS ARE CAPABLE OF BRINGING DOWN LARGE TREE LIMBS. LIGHT OBJECTS
SUCH AS TRASH CANS...POTTED PLANTS...LAWN FURNITURE AND AWNINGS
COULD BE TOSSED AROUND.

VERY HEAVY RAIN WITH RAINFALL AMOUNTS EXCEEDING OF ONE TO TWO INCHES
DURING THE NEXT HOUR CAN BE EXPECTED IN THESE AREAS. MOTORISTS
SHOULD DRIVE WITH CAUTION TO AVOID HYDROPLANING.

MWS

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
448 PM EDT TUE JUL 10 2007

NCZ041-042-077-102145-
HARNETT-JOHNSTON-WAKE-
448 PM EDT TUE JUL 10 2007

...STRONG THUNDERSTORMS WILL MOVE ACROSS SOUTHEASTERN WAKE...WESTERN
JOHNSTON AND EXTREME NORTHERN HARNETT COUNTIES THROUGH 545 PM EDT...

AT 448 PM EDT...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS OVER
ANGIER...OR ABOUT 10 MILES NORTHEAST OF LILLINGTON...MOVING NORTHEAST
AT 25 MPH.

SOME LOCATIONS AFFECTED BY THESE STORMS INCLUDE...ANGIER...COATS
CROSSROADS AND RURAL AREAS NEAR THE JOHNSTON AND WAKE COUNTY BORDER.

GUSTY WINDS OF 35 TO 45 MPH...VERY HEAVY RAIN AND DANGEROUS
CLOUD-TO-GROUND LIGHTNING CAN BE EXPECTED WITH THESE STORMS. THESE
WINDS ARE CAPABLE OF BRINGING DOWN LARGE SMALL LIMBS. LIGHT OBJECTS
SUCH AS EMPTY TRASH CANS... AND AWNINGS COULD BE TOSSED AROUND.

MWS

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
502 PM EDT TUE JUL 10 2007

NCZ039-102145-
RANDOLPH-
502 PM EDT TUE JUL 10 2007

...A STRONG THUNDERSTORM WILL MOVE ACROSS SOUTHERN RANDOLPH COUNTY
THROUGH 545 PM EDT...

AT 502 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
ULAH...OR ABOUT 7 MILES SOUTHWEST OF ASHEBORO...MOVING EAST AT 25
MPH.

THIS STORM WILL CROSS HIGHWAY 220 JUST SOUTH OF ASHEBORO BY 520 PM.

GUSTY WINDS OF 30 TO 40 MPH...SMALL HAIL AND DANGEROUS
CLOUD-TO-GROUND LIGHTNING CAN BE EXPECTED WITH THIS THUNDERSTORM.

VINCENT

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
507 PM EDT TUE JUL 10 2007

NCZ027-102200-
NASH-
507 PM EDT TUE JUL 10 2007

...STRONG SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS NASH COUNTY
THROUGH 600 PM EDT...

AT 507 PM EDT...DOPPLER RADAR INDICATED SHOWERS AND THUNDERSTORMS
WITH VERY HEAVY RAIN OVER DORTCHES...OR ABOUT OVER ROCKY MOUNT...
MOVING EAST AT 10 MPH.

THE STRONG THUNDERSTORMS WILL BE NEAR BATTLEBORO AROUND 530 PM EDT.

GUSTY WINDS OF 30 TO 40 MPH...SMALL HAIL AND DANGEROUS
CLOUD-TO-GROUND LIGHTNING CAN BE EXPECTED WITH THESE THUNDERSTORMS.

VERY HEAVY RAIN WITH RAINFALL AMOUNTS EXCEEDING ONE TO TWO
INCHES DURING THE NEXT HOUR CAN BE EXPECTED IN THESE AREAS.
MOTORISTS SHOULD DRIVE WITH CAUTION TO AVOID HYDROPLANING. MINOR
FLOODING OF LOW LYING AREAS...CREEKS...STEAMS AND SOME ROADS CAN BE
EXPECTED.

23

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
508 PM EDT TUE JUL 10 2007

NCZ078-102145-
WAYNE-
508 PM EDT TUE JUL 10 2007

...A STRONG THUNDERSTORM WILL MOVE ACROSS WAYNE COUNTY THROUGH 545 PM
EDT...

AT 508 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
EXTREME EAST CENTRAL WAYNE COUNTY...OR ABOUT 8 MILES NORTHEAST OF
GOLDSBORO...MOVING EAST AT 10 MPH.

LOCATIONS AFFECTED INCLUDE RURAL EASTERN WAYNE COUNTY... BETWEEN
EUREKA AND ELROY. OTHER STRONG THUNDERSTORMS WILL MOVE INTO WESTERN
WAYNE COUNTY AROUND 5:30 PM... AND AFFECT LOCATIONS FROM NEAR
FREMONT TO NAHUNTA TO GRANTHAM.

GUSTY WINDS OF 35 TO 45 MPH...VERY HEAVY RAIN AND DANGEROUS
CLOUD-TO-GROUND LIGHTNING CAN BE EXPECTED WITH THESE STORMS. THESE
WINDS ARE CAPABLE OF BRINGING DOWN SMALL TREE LIMBS. LIGHT OBJECTS
SUCH AS EMPTY TRASH CANS...LAWN FURNITURE AND AWNINGS COULD BE
TOSSED AROUND.

MWS

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
513 PM EDT TUE JUL 10 2007

NCZ042-102215-
JOHNSTON-
513 PM EDT TUE JUL 10 2007

...STRONG THUNDERSTORMS WITH VERY GUSTY WINDS WILL MOVE ACROSS
EASTERN JOHNSTON COUNTY THROUGH 615 PM EDT...

AT 513 PM EDT...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS OVER
MICRO...OR ABOUT 10 MILES EAST OF SMITHFIELD...MOVING EAST AT 10 MPH.

SOME LOCATIONS AFFECTED BY THESE STORMS INCLUDE...KENLY AND RURAL
EASTERN JOHNSTON COUNTY.

GUSTY WINDS OF 40 TO 50 MPH...VERY HEAVY RAIN AND DANGEROUS
CLOUD-TO-GROUND LIGHTNING CAN BE EXPECTED WITH THESE STORMS. THESE
WINDS ARE CAPABLE OF BRINGING DOWN LARGE TREE LIMBS. LIGHT OBJECTS
SUCH AS TRASH CANS...POTTED PLANTS...LAWN FURNITURE AND AWNINGS COULD
BE TOSSED AROUND.

MWS