Tonight:
Partly cloudy, with a low around 36. Calm wind.

Wednesday:
Partly sunny, with a high near 55. Light east wind.

Wednesday Night:
A chance of sprinkles after 2am. Mostly cloudy, with a low around 39. Calm wind.

Thursday:
Light rain likely, mainly after noon. Cloudy, with a high near 56. Calm wind becoming east between 4 and 7 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch possible.

Thursday Night:
Periods of rain. Low around 43. East wind around 7 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

Friday:
Periods of rain. High near 55. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

Friday Night:
Rain likely. Cloudy, with a low around 43. Chance of precipitation is 70%.

Saturday:
Rain likely. Cloudy, with a high near 56. Chance of precipitation is 70%.

Saturday Night:
Rain likely. Cloudy, with a low around 41. Chance of precipitation is 60%.

Sunday:
A chance of rain. Cloudy, with a high near 52. Chance of precipitation is 40%.

Sunday Night:
A chance of rain. Mostly cloudy, with a low around 37. Chance of precipitation is 30%.

Monday:
Mostly cloudy, with a high near 51.

Monday Night:
Mostly cloudy, with a low around 35.

Tuesday:
Partly sunny, with a high near 52.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
327 PM EST TUE MAR 9 2010

Weather Synopsis:
A WEAK AREA OF HIGH PRESSURE WILL SLIDE ACROSS OUR AREA TONIGHT INTO WEDNESDAY, THEN OFF TO OUR EAST DURING THE DAY WEDNESDAY. A LARGE STORM SYSTEM ORGANIZING ACROSS THE CENTER OF THE COUNTRY WILL GRADUALLY MOVE EASTWARD DURING THE NEXT SEVERAL DAYS. IT WILL ARRIVE IN OUR AREA DURING THE END OF THE WEEK AND LINGER RIGHT THROUGH THE WEEKEND. THE STORM SHOULD THEN BE GRADUALLY MOVING AWAY FROM OUR AREA MONDAY AND TUESDAY.

Near Term:
Until 6 Am Wednesday Morning - ANOTHER GREAT MARCH AFTERNOON ADDED TO THIS CONTINUED STRETCH WITH WALL-TO-WALL SUNSHINE AND TEMPERATURES WELL INTO THE 50S AND EVEN LOWER 60S. A SEA BREEZE DEVELOPED THIS AFTERNOON, KEEPING TEMPERATURES COOLER ALONG THE COAST. DESPITE THE LINGERING SNOWCOVER ACROSS THE FAR NORTHWEST ZONES, TEMPERATURES STILL SOARED WELL INTO THE 50S AT MOST LOCALES THERE. A 19Z SURFACE ANALYSIS PLACED A FRONTAL BOUNDARY FROM ABOUT SOUTHEASTERN CANADA TO SOUTHERN NEW ENGLAND. THERE IS NOT MUCH WITH THIS BOUNDARY, OTHER THAN A DEW POINT CHANGE. MEANWHILE, HIGH PRESSURE WAS LOCATED FROM THE CAROLINAS TO THE EASTERN GREAT LAKES. A LOW PRESSURE SYSTEM WAS OVER EASTERN KANSAS. AN UPPER AIR ANALYSIS PLACED CYCLONIC FLOW ACROSS THE NORTHEAST AND A MIDLEVEL RIDGE FROM THE MIDWEST TO THE SOUTHERN MID ATLANTIC REGION. A CLOSED LOW WAS OVER THE CENTRAL PLAINS WITH ANOTHER CLOSED LOW OVER THE FOUR CORNERS REGION. A WEAKENING CYCLONICALLY CURVED 300 MB JET WAS OVER THE PLAINS TO THE TENNESSEE VALLEY WITH A STRONGER JET LOCATED OVER MEXICO. HIGH PRESSURE WILL GRADUALLY SLIDE EASTWARD THROUGH TONIGHT AS A SYSTEM IN THE PLAINS TRIES TO MOVE EASTWARD. THE LATTER WILL TEND TO WEAKEN AS IT RUNS INTO MIDLEVEL RIDGING AND A MORE POTENT CLOSED LOW MOVES ACROSS THE FOUR CORNERS REGION. THE NORTHWESTERLY FLOW ON THE SOUTHWEST SIDE OF A DEPARTING TROUGH OVER THE NORTHEAST MAY HELP TO PULL SOME HIGH LEVEL CLOUDS OUR WAY. THE MIDLEVEL RIDGE AXIS HOWEVER IS FORECAST TO REMAIN TO OUR WEST, THEREFORE ONLY A GRADUAL INCREASE IN SOME CLOUDS ARE ANTICIPATED THROUGH THE OVERNIGHT. THE GFS HAS A MORE COMPACT SHORT WAVE THAT QUICKLY EJECTS NORTHEASTWARD OVERNIGHT TOWARD THE MID ATLANTIC, HOWEVER GIVEN THE DRY ATMOSPHERE AND THE LINGERING MIDLEVEL RIDGE, THIS FEATURE LOOKS TO BE OVERDONE /NOT MUCH MODEL SUPPORT/. THEREFORE, WE WILL JUST GRADUALLY INCREASE THE CLOUD COVER SOME FROM WEST TO EAST THROUGH THE OVERNIGHT. AS FOR TEMPERATURES, WE INITIALLY TOOK A BLEND OF THE GFS AND NAM MOS BUT THEN MADE SOME ADJUSTMENTS BASED ON MORE LOCAL AFFECTS INCLUDING LINGERING SNOWCOVER UP ACROSS THE NORTHWEST.

Short Term:
6 Am Wednesday Morning Through Friday - OUR TRANQUIL WEATHER /A BREAK FROM THE RATHER ACTIVE WEATHER LAST MONTH/ WILL BE COMING TO AN END AS A LARGE STORM SYSTEM IN THE CENTRAL PART OF THE NATION GRADUALLY MOVES EASTWARD. THE MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT ALOFT WITH THIS SYSTEM CLOSING OFF AND GRADUALLY SLIDING EASTWARD AS ENERGY CONTINUES TO REVOLVE AROUND IT. AS THIS SYSTEM DEVELOPS INTO AN EXPANSIVE CLOSED MIDLEVEL LOW, ITS EASTWARD PROGRESSION SHOULD TEND TO SLOW. THIS WILL ALLOW WAVES OF ENERGY TO ROTATE AROUND IT, WHICH WILL ACT UPON INCREASING MOISTURE ACROSS THE EASTERN UNITED STATES. THERE ARE SOME DIFFERENCES HOWEVER WITH THE TIMING OF THE INDIVIDUAL PIECES OF ENERGY ROTATING NORTHEASTWARD INTO THE MID ATLANTIC BY FRIDAY. BACKING UP A BIT, A WARM FRONT IS FORECAST ORGANIZE TO OUR SOUTH DURING WEDNESDAY AND THURSDAY. THE GFS CONTINUES TO SCOOT AN IMPULSE SORT OF THROUGH THIS MIDLEVEL RIDGE DURING WEDNESDAY. THE AIR MASS WILL CONTINUE TO MOISTEN UP DURING WEDNESDAY, THEREFORE ANY PRECIPITATION WITH THIS FEATURE MAY DRY UP AS IT TRACKS EASTWARD /SPRINKLES PERHAPS/. AN EXAMINATION OF THE GFS 700 MB OMEGA FIELD AND ALSO THE 500 MB VORTICITY MAKES US LEAN MORE TOWARD THIS MODEL POSSIBLY OVERDOING THIS FEATURE. AS A RESULT, WE WILL KEEP POPS BELOW SLIGHT CHC. FOR THURSDAY AND FRIDAY, ISENTROPIC LIFT CONTINUES AS 850 MB WAA STRENGTHENS WITHIN AN INCREASING LOW TO MID LEVEL FLOW. THE MIDLEVEL RIDGE AXIS IS FORECAST TO BE GRADUALLY MOVING ACROSS OUR AREA DURING THURSDAY. AS A RESULT, THE ATMOSPHERE WILL GRADUALLY MOISTEN UP AS THE FLOW OFF THE OCEAN STRENGTHENS. THE OVERALL SYNOPTIC LIFT HOWEVER IS NOT REAL STRONG AND ORGANIZED, THEREFORE ANY PRECIPITATION LOOKS TO BE ON THE LIGHTER SIDE. AS A RESULT, WE BEGAN TO INCREASE THE POPS FROM SOUTHWEST TO NORTHEAST DURING THURSDAY WITH THE HIGHEST POPS ACROSS THE SOUTHWEST ZONES. SOME OF THE MODEL GUIDANCE INDICATES SOME INSTABILITY DEVELOPING THURSDAY ALTHOUGH THIS IS CONFINED TO THE LOWEST LEVELS AND RATHER SHALLOW /NOT DEEP ENOUGH FOR CHARGE SEPARATION/. AS A WARM FRONT ALOFT CROSSES THE AREA THOUGH THURSDAY NIGHT, THE ATMOSPHERE CONTINUES TO SATURATE WITH THE ISENTROPIC LIFT REACHING DEEPER INTO THE SATURATED LAYER. THIS COMBINED WITH STRENGTHENING PVA AND FRONTOGENETIC FORCING SHOULD LEAD TO RAIN BECOMING MORE WIDESPREAD AS WE GO THROUGH FRIDAY. WE WENT AHEAD AND BUMPED UP POPS TO CATEGORICAL THURSDAY NIGHT, THEN CATEGORICAL NORTH AND CENTRAL FRIDAY WITH SOME TAPERING OFF TO THE SOUTH. AS THE MASSIVE CLOSED LOW TO OUR WEST GRADUALLY MOVES CLOSER, STRONGER LIFT IS EXPECTED TO ARRIVE ACROSS OUR AREA AS WE GO BEYOND THIS TIME FRAME. AS A RESULT, THE HEAVIEST QPF SHOULD OCCUR DURING THE LONG TERM PORTION OF THE FORECAST. THE HEIGHT FALLS COUPLED WITH STRONGER WAA ON THE EAST SIDE OF THE CLOSED LOW WILL TEND TO TIGHTEN UP A THERMAL GRADIENT. THIS SHOULD INITIATE CYCLOGENESIS IN THE MID ATLANTIC REGION LATE THURSDAY AND FRIDAY. THIS SURFACE LOW WILL THEN GRADUALLY TRACK NORTHEASTWARD. THE SLOW MOVEMENT OF THIS ENTIRE SYSTEM MAY KEEP THE TRUE SURFACE WARM FRONT MOSTLY SOUTH AND EAST OF OUR CWA. TO DEMONSTRATE THE AMOUNT OF MOISTENING THE ATMOSPHERE WILL BE UNDERGOING FROM THE NEAR TERM THROUGH THE SHORT TERM, WE LOOKED AT THE TREND OF THE PW VALUES. THESE ARE FORECAST TO INCREASE FROM ABOUT 0.25 OF AN INCH /TONIGHT/ TO ABOUT 1.25 INCHES /FRIDAY/. AS FOR TEMPERATURES, WE GENERALLY UTILIZED A GFS/NAM MOS BLEND ALTHOUGH DID LEAN A BIT MORE TOWARD THE MILDER NAM VALUES DESPITE THE INCREASED CLOUD COVER AND ANTICIPATED RAIN. THIS MAY BE A SETUP WHERE DESPITE THE CLOUDS AND BUILDING PRECIPITATION, ENOUGH LOW-LEVEL WARM ADVECTION /SOUTHEASTERLY FLOW/ HELPS TO DRIVE MILDER AIR INTO THE CWA /ESPECIALLY SOUTH AND EAST/.

Long Term:
Friday Night Through Tuesday - UNSETTLED WEATHER IN THIS TIME FRAME AS A STRONG UPPER LOW IN THE MIDWEST MOVES SLOWLY EAST. THE SURFACE LOW ASSOCIATED WITH THIS SYSTEM WILL BRING AN EXTENDED PERIOD OF RAIN TO OUR AREA. THE RAIN COULD BE HEAVY AT TIMES, ESPECIALLY LATE FRIDAY NIGHT INTO EARLY SATURDAY NIGHT. ONE TO THREE INCHES OF RAIN WITH LOCALLY FOUR INCHES OR MORE COULD FALL BEFORE THE STORM MOVES OFF TO THE EAST MONDAY INTO TUESDAY. MILD TEMPERATURES AHEAD OF THIS SYSTEM WILL HELP ERODE THE LINGERING SNOWPACK PRIOR TO THE RAINFALL, BUT WITH THE AMOUNT OF RAIN EXPECTED COMBINED WITH SNOWMELT, THE POSSIBILITY OF FLOODING COULD CERTAINLY BE A PROBLEM. WE WILL CONTINUE TO HIGHLIGHT THIS POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK. AS THE LOW BEGINS TO PULL OFF TO THE EAST, COLDER AIR WILL BE PULLED INTO OUR AREA AND THE RAIN COULD MIX WITH OR CHANGE TO SNOW IN OUR NORTHERN AREAS FOR A TIME SUNDAY NIGHT INTO MONDAY. THE RAIN IS EXPECTED TO END BY MONDAY NIGHT AND FAIR WEATHER WILL TAKE OVER ON TUESDAY. DAYTIME HIGH TEMPERATURES WILL BE QUITE MILD ON SATURDAY WITH READINGS GENERALLY IN THE 50S. THEY`LL DROP A BIT FOR SUNDAY, MONDAY, AND TUESDAY RANGING FROM THE MID 40S NORTH TO THE LOWER AND MID 50S SOUTH. OVERNIGHT LOWS WILL BE IN THE UPPER 30S AND 40S FRIDAY NIGHT, UPPER 30S TO MID 40S SATURDAY NIGHT, IN THE 30S TO LOW 40S SUNDAY NIGHT, AND MAINLY IN THE 30S MONDAY NIGHT.

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