Quantitative Precipitation Forecast
Issued by NWS

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826
FXUS04 KWBC 071000
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
500 AM EST SUN FEB 07 2016


FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID FEB 07/1200 UTC THRU FEB 10/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1

...EASTERN SEABOARD...

LOW PRESSURE FORMING OFF THE SOUTHEAST COAST WILL INTENSIFY TO
NEAR 980 MB BY MONDAY MORNING...WITH THE UPSTREAM MID LEVEL TROUGH
DIPPING TO 3 STANDARD DEVIATIONS BELOW CLIMATOLOGY IN THE 500 MB
HEIGHT FIELD. A BAROCLINIC ZONE HAD PREVIOUSLY BEEN ESTABLISHED
OFFSHORE...WHICH WILL ENCOURAGE THE SYSTEM ALONG WITH A FAIRLY
PRONOUNCED EASTWARD COMPONENT OF MOTION WHILE ALSO LIFTING
NORTHWARD. THIS MEANS THE HEAVIEST PRECIPITATION WILL OCCUR NEAR
THE SC/NC COASTLINE EARLY IN THE PERIOD AS THE LOW BEGINS TO
INTENSIFY AND THE INFLUENCE OF HEIGHT FALLS EXPANDS INLAND. MODELS
ARE FAIRLY CONSISTENT IN FORECASTING THE HEAVIEST RAIN...INVOLVING
NEAR-SFC BASED INSTABILITY...TO REMAIN OFFSHORE...WHILE LESSER BUT
NONETHELESS SIGNIFICANT PRECIPITATION OCCURS ALONG THE SC/NC COAST
AND OUTER BANKS WITH AREAL AVERAGE 1 TO 2 INCHES NEAR THE
SHORE...AND 0.10 TO 0.25 INCHES AS FAR WEST AS FLORENCE TO
RALEIGH. ONE OF THE BIGGER QUESTION MARKS IS HOW MUCH PRECIP WILL
FALL UP THE COAST INTO THE MID ATLANTIC AND SOUTHERN NEW ENGLAND.
THE ZONE FROM SOUTHEAST VA TO NJ TO EASTERN MA WILL EXPERIENCE
HEIGHT FALLS PERHAPS SIGNIFICANT ENOUGH TO PRODUCE NOTEWORTHY
PRECIPITATION TODAY AND TONIGHT PER ABOUT HALF OF THE MODEL
GUIDANCE. THE OTHER HALF OF THE GUIDANCE IS DRY. WITH DRY AIR IN
PLACE INITIALLY FROM VA NORTHWARD...SOME EASTERLY WARM ADVECTION
MAY BE REQUIRED TO GET ANYTHING HEAVIER THAN A FEW HUNDREDTHS OF
AN INCH...AND THIS APPEARS MORE LIKELY TO OCCUR INTO SOUTHERN NEW
ENGLAND BY SUNDAY NIGHT PER THE MID LEVEL FORECASTS FROM THE
GFS/ECMWF RELATIVE TO THE SHAPE OF THE COASTLINE.

THIS THINKING WOULD SEEM TO FAVOR SOLUTIONS LIKE THE GEFS
MEAN...NAM CONUS NEST...AND TO SOME EXTENT THE GEM REGIONAL. OUR
IN-HOUSE BIAS-CORRECTED ENSEMBLE IS ALSO CLOSE TO THESE...ALTHOUGH
IT MAY BE SPREADING PRECIP A BIT TOO FAR INLAND UNDER THE
INFLUENCE OF THE MORE AGGRESSIVE SREF MEAN. TO TEMPER THAT...WE
TOOK A 40/40/20 BLEND OF OUR BIAS-CORRECTED ENSEMBLE WITH THE 18Z
GEFS MEAN AND 00Z NAM CONUS NEST...AND USED THAT OUTPUT AS A
TEMPLATE FOR ADJUSTING THE PREVIOUS WPC FORECAST...TO MAINTAIN
CONTINUITY.


...UPPER MIDWEST / GREAT LAKES / OHIO VALLEY...

THE HEIGHT FALLS THAT HAVE BEEN RACING EASTWARD FROM THE NORTHWEST
U.S. INTO THE NORTHERN PLAINS WILL BEGIN TO SLOW AS LARGE SCALE
AMPLIFICATION OCCURS ACROSS THE COUNTRY...RESULTING IN A LARGE
TROUGH OVER THE MIDWEST. WHILE MODERATE TO STRONG LIFT WILL OCCUR
ON A BROAD SCALE...PRECIPITATION WILL BE BATTLING DRY AIR AT LOW
LEVELS. THERMODYNAMICS AND/OR DEEP LAYER RELATIVE HUMIDITY SHOULD
PROVE MORE FAVORABLE FOR 0.10 TO 0.25 INCH MELTED ACCUMULATIONS
WITH NORTHWARD EXTENT...NEAR THE CENTER OF THE H7-5 TROUGH...FROM
NORTHERN MINNESOTA TO NORTHERN LOWER MICHIGAN. PRECIPITATION
EFFICIENCY WILL BE AIDED SOMEWHAT BY LAKE EFFECT ON LOCAL
SCALES...BUT ALSO AN ARCTIC FRONTAL BOUNDARY DRAPED ACROSS THE
TRACK OF THE SURFACE LOW PRESSURE CENTER THROUGH THIS REGION.
FARTHER SOUTH...MODELS PRODUCE WIDESPREAD VERY LIGHT ACCUMULATING
PRECIPITATION AS THE TROUGH DIGS AND ARCTIC AIR PUSHES THROUGH THE
MID MISSOURI VALLEY...AND DOWNSTREAM FLOW BECOMES INCREASINGLY
DIFLUENT ALOFT TOWARD THE OHIO VALLEY. THE PREVIOUS WPC FORECAST
PROVIDED A GOOD STARTING POINT...AND WE REFINED SOME OF THE
DETAILS USING HIGHER RESOLUTION GUIDANCE...BUT WITH LITTLE OVERALL
CHANGE TO THE GOING FORECAST.


DAYS 2/3...

...UPPER MS VALLEY/GREAT LAKES TO MID-ATL...

A PHASING SHORT WAVE TROUGH EMERGING INTO THE UPPER MIDWEST TODAY
WILL HELP ESTABLISH AN ANOMALOUS UPPER TROUGH OVER THE EAST MON
AND TUES. THE DISTURBANCE WILL HAVE CLOSED OFF A LOW ACROSS THE
UPPER MS VALLEY INTO THE GREAT LAKES BY THE TIME THE DAY 2 PERIOD
BEGINS ON MONDAY MORNING... WHILE ADDITIONAL UPPER DYNAMICS DIG
SOUTH AND EAST THROUGH THE PLAINS/MS VALLEY. A LARGE CLOSED MID TO
UPPER LOW WILL BE CENTERED OVER PARTS OF THE SOUTHERN GREAT LAKES
AND PARTS OF THE OH VALLEY WHICH HELPS PUSH A FRONT THROUGH THE
OH/TN VALLEYS AND APPALACHIANS...WHILE A JET STREAK ROUNDS THE
ROUNDS THE BASE OF THE TROUGH INTO THE SOUTHERN MID-ATL REGION.
THIS SHOULD SPELL MODEST QPF AMOUNTS OF A .25 INCH OR GREATER
AHEAD OF THE FRONTAL ZONE WITH LACK OF GULF MOISTURE AND POSSIBLE
ENHANCED AMOUNTS DOWNWIND OF LAKE SUPERIOR INTO NRN WI AND THE WRN
UP OF MI. THE UPPER DYNAMICS THEN REACH THE MID-ATL COAST WILL
BEGIN TO INDUCE AN AREA OF SURFACE LOW PRESSURE TUESDAY AND
TUESDAY EVENING.  THE LOW IS STILL EXPECTED TO PROCEED AWAY FROM
THE COAST. HOWEVER... A POSSIBLE TROUGH AXIS/TROWAL COULD SET UP
FROM THIS INTENSIFYING LOW BACK TO THE SURFACE RESEMBLANCE OF THE
UPPER LOW OVER THE GREAT LAKES. THIS COULD ALLOW A SPIKE OF
MOISTURE TO FOCUS ALONG THIS CONVERGENCE AXIS FOR HEAVIER QPF
AMOUNTS AND SNOW. THE OPERATIONAL MODELS AND ENSEMBLE GUIDANCE
STILL SHOWS LARGE SPREAD ON THIS SYSTEM AND RESULTANT QPF... WITH
THE RANGE OF SOLNS STILL HAVING THE AXIS OF HEAVIEST PCPN SETTING
UP FROM ANYWHERE FROM AS FAR SOUTH AS VA TO AS FAR NORTH AS
NYC/NJ/NERN PA BACK TO THE APPALACHIANS AND LAKE ERIE.

...EASTERN SEABOARD...

A DYNAMIC SHORT WAVE IMPULSE NEAR THE SOUTHEAST COAST EARLY THIS
MORNING WAS HELPING INDUCE A WAVE WHICH WILL GO THROUGH RAPID
CYCLOGENESIS LATER TODAY. BY THE TIME EARLY MON ARRIVES THIS DEEP
LOW AND NEG TILT UPPER TROUGH WILL BE WELL OFFSHORE OF THE MID-ATL
COAST WITH PERHAPS THE WESTERN OUTER EDGE OF THE LARGE PRECIP
SHIELD CLIPPING THE OUTER BANKS OF NC. THE SYSTEM TRANSITIONING
DOWNSTREAM DUE NORTH AND APPROACHING THE CANADIAN MARITIMES LATE
IN THE PERIOD... MOISTURE COULD SPREAD ACROSS PARTS OF NEW ENGLAND
DESPITE THE STRONG SURFACE RIDGE IN PLACE. THE HEAVIEST QPF VIA
THE GFS AND ECMWF BLEND SHOULD OCCUR ACROSS THE CAPE OF MA WITH
POSSIBLE .25 INCH AMOUNTS DUE TO A COMBINATION OF DYNAMIC FORCING
OR THROUGH OCEAN EFFECT PROCESSES.  SEE THE LATEST GUIDANCE FROM
THE WPC WINTER WEATHER DESK SINCE AT LEAST SOME OF THE PCPN WILL
BE FALLING AS SNOW.


GRAPHICS AVAILABLE ON THE WEB AT WWW.WPC.NCEP.NOAA.GOV

BURKE/BANN


24HR QP VT 08/12Z
 0.01 416638 420641 424644 430651 437665 438669 436676 434689
      430699 429705 426712 421721 408738 405743 401747 393755
      388758 382760 378762 375767 370777 364787 361792 357795
      349802 339809 328814 323814 318814 308812 298807 291799
      284791 281788 277786 272784 265783 258783 252784 246784
      242781 243778 245774 250764 257754 264747 271741 290728
      298721 305715 322700 327692 333684
 0.01 538205 538188 537183 536182 533176 529171 527169 525170
      521167 516167 510167 504167 501167 501169 502176 507188
      511192 516198 518203 519206 519212 522216 523219 526220
      530218 534214 538205
 0.01 518276 519269 519264 518260 517255 511237 507230 505228
      501227 497224 495220 492212 486207 483206 480207 471208
      465211 464219 470218 478217 483218 486220 491221 494223
      497226 500235 502243 480228 472226 466229 465233 466239
      464242 459242 455246 450252 447255 444259 446265 453269
      461271 471274 475275 478275 487277 490279 492282 502287
      505289 509288 514283 518276
 0.01 512276 513274 512272 512271 511270 510269 509270 508272
      508275 509276 510277 512277 512276
 0.01 517957 516952 516943 514937 514929 512925 512918 509907
      504880 503873 503862 505847 504834 501822 498812 494802
      489794 487789 483785 480781 477779 472775 468774 463772
      460770 456771 454776 455783 452784 448782 444782 406800
      389808 381813 373817 366823 359833 357837 357844 356849
      354852 352857 355861 362865 364868 364872 368880 371884
      374884 377880 379878 382877 391873 396871 398869 402869
      409864 415863 418864 419867 420871 423872 428864 429859
      430856 433854 435854 438856 440859 444862 446863 448867
      449876 450882 448887 444889 443892 439892 434892 430890
      426890 418886 413884 409884 407882 403882 397883 390888
      385897 381905 380911 380917 380923 382927 386929 388932
      402945 414961 421969 426977 437988 445993 456998 461998
      465996 470996 473998 473001 475012 481021 486027 493027
      498020 503008 507997 510983 514970 517957
 0.01 496655 495649 492644 488642 484641 478642 475645 469654
      464664 462669 460676 458686 454698 450708 449721 446727
      445732 445740 446744 448744 456723 459712 464703 470695
      479686 485679 492669 494667 496663 495657 496655
 0.01 253826 253820 251816 249812 247808 245804 243800 240803
      240809 241815 242821 244825 246829 249831 252828 253826
 0.25 502278 503273 503268 501262 498257 494251 491247 488244
      486248 487253 488255 491261 493267 496273 500277 502278
 0.25 490881 489867 489859 487854 483847 479837 475828 472816
      470811 467809 460804 452802 443802 438803 436806 435809
      437812 442812 445812 449814 454815 456818 460821 462826
      463832 463839 465850 472856 477863 481872 485882 488885
      490881
 0.25 471910 471907 471905 471902 471900 471897 470896 469895
      468895 467895 465898 464900 464903 464905 464908 464910
      464913 465914 467915 469914 470912 470911 471910
 0.25 419673 418665 416659 414655 410651 406648 401647 395647
      390649 377654 369659 359667 351674 342681 336688 329698
      321706 306720 300728 295739 289748 284756 275764 271768
      270773 275774 281775 285775 290778 294789 298794 302798
      311803 320805 327804 333802 343796 352789 355786 358781
      368760 397728 404719 409711 414698 417686 419673
 0.50 413675 412668 410661 405653 402651 396650 385653 375657
      368662 360669 353676 340688 327703 315716 309724 307728
      306733 301742 297749 294752 292758 294763 299763 301765
      300769 297779 298785 300791 306796 315800 324801 330800
      336797 344792 350786 354779 364760 374746 388731 399717
      404708 408698 411687 413675
 1.00 404680 404673 402667 398661 390658 386657 381659 368669
      362675 355681 342691 336697 330704 321716 317724 315734
      313742 313747 314753 314759 313765 309771 305779 304783
      306786 313792 321795 329795 337793 341790 344786 348778
      351771 355764 365749 370743 375738 381730 386724 390716
      394709 401692 403686 404680
 1.50 397682 397676 396673 391668 387666 383665 377668 355688
      344698 340698 336701 332707 325719 322727 321736 321745
      322754 320763 316769 312775 311778 311782 313787 316789
      322791 331791 338788 342781 346774 352762 360749 369739
      373733 378725 391699 395690 397682
 2.00 390683 387677 382678 375682 369686 360694 354699 352705
      348706 345705 340704 338706 336710 333715 329721 327726
      326735 326740 328744 331751 330756 327762 323767 318771
      315776 314780 316785 322788 330787 336784 340778 342772
      345766 348761 356750 372729 378717 384703 388694 390683
 3.00 363729 360728 357729 353735 344744 341749 338755 335761
      330766 321774 319779 322781 327779 332777 337772 344761
      347756 351751 359741 362735 363729
 3.00 337729 337728 336727 335727 334728 334730 334732 336733
      336732 337730 337729
 4.00 331770 334769 336766 336765 335765 333767 331770 331770

24HR QP VT 09/12Z
 0.01 459624 460634 463640 469659 467677 467685 464690 451713
      442723 431730 429731 427735 425744 424748 426753 430757
      433760 436761 440765 444771 450772 461775 471777 476779
      480783 486788 488789 489795 490798 491804 494813 500829
      503835 504839 505843 505854 504859 504864 504871 501878
      495889 492895 487899 486910 487919 487925 489929 487937
      483943 477945 466937 461941 456943 442947 439943 438935
      441930 439925 440920 438916 431916 422924 417928 412924
      409924 407922 401917 399915 396915 395916 394919 396922
      399927 404930 412935 420947 422950 421954 414956 403948
      391942 384938 380934 377929 371925 366918 367914 370913
      375911 378911 382909 380904 378902 372898 369891 362880
      357874 351871 345869 343867 339869 334869 330868 326868
      321872 315873 312871 311868 310863 313858 315852 318848
      321840 323824 320821 317823 313829 309834 307836 303836
      300835 296835 292835 294832 296826 299821 303817 298814
      291812 284810 282809 283807 282798 283782 291771 307751
      321731 335712 351689 368670 373666 380664 387663 390669
      392671 395670 401666 408662 411661 413656 417638
 0.01 543041 539038 533037 528033 524028 516021 508014 504013
      503011 496010 494011 494016 494020 496023 496026 499029
      502032 507035 512040 520046 525049 531052 536049 539045
      543041
 0.01 455920 455918 455915 453914 452913 450916 452918 452920
      454923 455920
 0.01 351769 349767 347766 346767 345768 344770 344771 343772
      342773 341775 343777 344776 346774 348772 348771 349771
      351769
 0.01 287837 286835 286833 285831 284829 284828 282827 282825
      281825 280825 278825 277826 277828 278830 278832 278834
      280836 280838 281838 282840 283840 284840 285839 286838
      287837
 0.01 254816 253812 251809 251806 252802 248802 246805 244809
      243813 243819 244825 247827 249824 251820 253817 254816
 0.25 478872 476870 474869 471868 469867 467868 467873 468875
      469880 470883 471886 473889 475887 476883 477880 477875
      478872
 0.25 474808 475801 474795 469790 461792 456791 449790 443786
      436785 431791 430795 431797 425801 421803 419806 424808
      438809 443809 446810 449816 453824 458829 463834 465834
      467830 471823 473815 474808
 0.25 454656 452649 450645 448643 445639 441637 435636 432640
      427649 421660 414669 407677 402680 397682 394684 391683
      386682 381679 376679 367685 360693 344710 338717 331726
      325736 320745 315754 310764 306776 305782 306786 310789
      315787 323780 337764 351749 360740 369734 376732 381729
      382726 385724 388721 395720 401720 405722 410722 417721
      426715 435706 441697 445687 450677 452671 453666 454656
 0.25 417809 413803 412797 409794 405792 405785 403780 401775
      398772 393770 388768 386769 386773 389778 392784 392788
      389792 385795 377802 371810 366813 364816 358824 353833
      351838 354843 361835 364831 366830 367831 372829 376826
      386822 397819 407816 417809
 0.50 466809 466804 465801 463800 460800 458800 455803 454806
      454811 455816 456819 458820 460819 463817 464814 465812
      466809
 0.50 441665 441657 439651 437648 434646 430653 426661 422669
      418676 416679 412681 403685 397689 390693 385696 383699
      383704 386706 390707 393705 400701 410699 414698 415703
      416706 419707 422704 426696 430688 435683 439675 441666
      441665
 0.50 377705 378698 374695 369696 357707 349712 342716 338723
      333730 329736 326743 323751 322760 324764 328764 334760
      345749 356738 361731 365724 369716 373710 377705
 1.00 342737 341736 340736 338738 336740 335742 335743 334745
      333745 334746 335745 337745 339743 339742 340741 341740
      342738 342737

24HR QP VT 10/12Z
 0.01 518083 514074 509067 502062 495056 490050 488054 488060
      489064 492067 496069 499072 505080 511087 514089 516088
      517085 518083
 0.01 521025 521015 519009 516005 510001 505998 501997 489995
      482994 478996 473997 467000 463003 459003 448997 445995
      441998 438001 435001 429998 425998 425001 426007 427011
      429013 433018 437021 443023 448025 456026 461029 464032
      472042 474045 477046 480046 482044 485042 489043 490045
      493046 497047 498049 504050 510051 516049 519049 518043
      516039 516034 518032 521025
 0.01 483692 482684 480678 479671 480664 478660 476657 469651
      466649 464654 463660 460664 456664 455663 450664 442674
      437683 432690 429692 427690 426683 424670 423663 421658
      417657 412657 392669 390682 385690 379696 374703 366709
      358711 353715 348716 345719 342723 338727 327741 324750
      323754 321758 317767 316774 317783 320785 326785 330782
      334779 340772 347765 353759 355759 358763 365772 370781
      374783 376786 375789 372799 370805 367809 360815 355821
      353830 345838 339840 338845 340856 344860 346864 351870
      355874 360874 364876 368876 371873 375875 398874 410877
      418882 441880 451879 453879 456882 456888 456892 455896
      456901 463910 465913 469910 474902 480894 486886 491867
      493853 493848 492845 491841 483814 477786 472764 474750
      476740 478724 478719 479716 479709 483692
 0.01 456010 456008 455006 454005 454003 453000 451001 450003
      449005 448006 446006 444005 443007 444008 445010 446010
      448011 448012 449013 451013 453014 454013 454012 456010
 0.25 401718 400708 397702 393706 388712 385718 384725 382731
      382736 384741 396769 398777 399782 396789 394792 391794
      385799 382803 379809 373815 369819 364821 362825 367831
      370832 374832 377827 381811 399793 403788 402782 404764
      401750 400743 401732 401718

$$





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