Quantitative Precipitation Forecast
Issued by NWS

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000
FXUS04 KWBC 070855
QPFPFD

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


PRELIM 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 421641 425644 432655 438667 436678 433691 429704
      419724 416729 412734 404743 396752 388758 382759 378763
      374767 371774 365796 362803 359807 355811 349815 340819
      336822 329823 324825 317826 311825 306822 301819 298816
      291808 285799 277790 274787 269784 264783 257783 250784
      245783 242779 245774 250766 255757 262749 271741 289729
      322700 327691 333684
 0.01 538205 538188 533176 530174 528170 525170 520167 516167
      509167 504167 501167 501170 502176 507188 512192 516198
      518204 519212 522217 526220 530218 534214 538205
 0.01 518276 519269 519264 518258 516253 511237 506230 503227
      499226 494218 492212 486207 477207 471208 465211 464219
      472217 476218 478217 482218 486220 492221 495223 497227
      501236 502243 500246 498243 493235 486231 480228 472226
      468227 466230 465240 463242 459242 454246 449253 444260
      446265 454269 463272 471274 475275 478275 487278 494283
      502287 506289 509288 515283 518276
 0.01 512276 513274 512272 512271 511270 510269 509270 508272
      508275 509276 510277 512277 512276
 0.01 517957 516951 516942 514936 514929 510913 509907 508900
      505885 503872 503859 505847 504834 501821 496809 492797
      486788 482783 479779 475777 468774 463772 460770 456772
      454777 455781 454785 449782 443782 439784 431789 424792
      415796 406800 396804 389808 379814 370820 367822 363826
      359833 357837 357844 356849 354852 352858 355862 362865
      366876 368880 371884 374884 376881 380878 384875 402869
      410864 415863 418864 419867 421872 424872 425869 428864
      429859 430856 432855 435854 438856 443861 446863 448865
      448869 449876 450882 447887 444889 442892 439892 434892
      413885 409884 407882 397883 394885 392886 390888 385897
      382901 380906 380918 380925 385929 391936 395938 397941
      404947 409956 410959 414961 421970 426978 433983 437988
      441990 448995 455998 461998 465996 470996 472997 473001
      476013 481022 488028 493027 496023 501014 503006 510983
      512976 515968 516961 517957
 0.01 496655 495648 491643 484641 478643 476643 474647 470651
      469654 464665 461671 460676 457688 455693 454698 450710
      450716 449721 446727 445733 445741 446744 448744 456723
      460711 464703 472693 479686 492669 494666 496663 496655
 0.01 253826 253820 251816 249812 247808 245804 243800 240803
      240809 241815 242821 244825 246829 249831 252828 253826
 0.25 502278 503272 503268 501262 498257 494251 491247 488244
      486248 487253 488255 491261 493267 496273 500277 502278
 0.25 490881 489865 489858 487854 483846 479837 475827 472816
      470811 466808 460804 451802 443802 438803 435807 437812
      442812 445812 450814 454815 456818 460822 462827 463832
      463839 464846 466851 472856 478863 481872 485883 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 418664 416659 413653 408649 404647 399647 390649
      377654 366661 359667 351674 342682 334690 329698 321706
      305722 302726 299730 295739 289748 282758 275764 271768
      270773 275774 281775 287776 291780 295791 301799 309806
      314809 320810 326810 331809 340804 349798 353793 356788
      360777 364769 370759 378749 392734 399726 406716 410707
      414696 418683 419673
 0.50 413675 412667 410660 407655 403652 395651 384654 374658
      364665 351678 343684 336692 324706 318713 311722 308725
      306730 303738 292756 300768 297779 298785 299790 306797
      312801 317803 321804 328804 335802 342797 348791 351787
      353782 358771 363762 368755 373748 381739 393725 398718
      404708 408699 411689 412680 413675
 1.00 404680 404673 402667 400662 397660 390658 386657 381659
      355681 340693 334698 330705 320718 316726 315733 312754
      314763 311769 306776 305781 305787 311792 317795 324797
      330797 335795 342790 345785 353767 362754 382729 387721
      392713 399697 403687 404680
 1.50 397682 397676 396673 390667 386666 382665 377668 371675
      365679 354688 342698 338699 335702 332707 327714 324721
      322728 321735 316769 312775 310779 311785 316790 322792
      331791 337789 340787 346774 348767 352760 360749 370737
      375732 378726 391699 395689 397682
 2.00 390683 387677 384678 381679 368684 363688 356693 354695
      353698 351704 348706 345705 339705 333715 329721 327728
      326735 327744 330751 328759 325764 320769 316774 315777
      314782 319787 322788 326788 331787 335785 337783 342772
      345765 349759 356750 361745 365738 372729 376723 379716
      384703 388693 390683
 3.00 363729 360728 356730 353735 344744 340750 338755 334762
      330766 321776 321778 321782 327781 333777 337773 344761
      347755 351751 359741 362734 363729
 3.00 337729 336727 335727 334728 335730 335732 336732 337730
      337729

24HR QP VT 09/12Z
 0.01 461623 460631 461636 463640 469659 467676 467684 464690
      460697 456704 453710 448715 440723 431731 426736 425744
      424747 426753 430757 436761 440765 444771 450772 460775
      473778 477780 482784 488788 490797 491805 494813 497819
      500829 505843 505854 504858 504864 504869 503873 500880
      494892 487903 486907 486912 487922 487927 489929 487937
      484942 477945 472942 468937 456943 442947 440945 438937
      440931 439924 440918 436916 431916 422924 417928 412924
      409924 407922 403917 396915 396916 394919 396921 398925
      403929 410932 414937 421948 422952 420955 412955 403948
      397944 391942 382936 377930 372926 368921 366916 368913
      372912 378911 381909 380905 376902 369891 362880 357874
      352871 341867 338869 334869 331868 327868 321872 316873
      312869 310867 310863 313856 316851 319846 320843 321838
      323824 320821 316824 313829 309834 307836 303836 301835
      296835 293835 293833 295827 299822 303817 297814 284810
      282809 283806 282796 283790 283783 291771 307752 320733
      336711 351690 368670 370668 373666 382663 386663 388664
      390669 393671 404664 410661 412659 413656 415646 417638
 0.01 543041 539038 533037 528034 524028 516021 508014 505013
      503011 496010 495010 494015 494020 496023 496026 499028
      502032 507035 512040 520046 524049 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 472792 469790 462792 456791 449790
      443786 436785 433788 431791 430795 431797 425801 419805
      419807 424808 438809 445810 449816 453824 458829 463834
      465834 467830 471823 473815 474808
 0.25 451657 450648 447642 444638 439636 435636 432640 426651
      416670 410678 397682 392683 386682 378678 372681 368684
      361692 346707 340714 333724 327732 322741 312760 308770
      305781 305786 310789 315788 319785 332769 338762 346754
      361739 366737 369733 373733 377729 382720 394717 418713
      426705 433698 440689 445679 449668 451657
 0.25 417809 414804 412802 412798 409794 405792 405786 404780
      401775 398772 389768 387769 386772 389778 392784 392787
      389792 385795 378802 371810 364816 358824 353833 351838
      354843 361836 364831 366830 367831 372830 376827 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 439660 439654 437649 435646 433648 425662 419676 415682
      407684 392692 385696 383699 383704 388707 392706 395703
      400700 404698 408697 415693 422689 426681 428673 433669
      437663 439660
 0.50 379700 379697 377695 374694 370695 366698 360704 352710
      344715 339720 330735 326743 323752 322756 322763 325765
      328764 336758 342752 355739 360734 364726 368718 374711
      378706 379700
 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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