FXUS04 KWBC 181847
QPFPFD
 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
147 PM EST THU MAR 18 2004
 
PRELIM DAY 1 AND DAY 2 QPF DISCUSSION
VALID MAR 20/0000 UTC THRU MAR 21/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 

DAY 1...

LATEST WV IMAGERY IS SHOWING DARKENING ACRS THE UPR MS VALLEY IN
ASSOC WITH THE SHRTWV MOVG SEWD INTO THE LOWER LAKES.  THIS IS
SUPPORTING THE OVERALL MODEL SOLN OF THIS SHRTWV AMPLIFYING AS IT
PUSHES ACRS THE LOWER LAKES AND MID ATL TONIGHT AND INTO FRI.  FOR
DAY 1...THE ETA AND GFS ARE IN VERY GOOD AGRMNT WITH THE TRACK AND
INTENSITY OF THIS SYSTEM.  THE PCPN SHIELD PRESENTLY AHEAD OF THIS
VORT OVR THE LOWER LAKES SHOULD INCREASE IN INTENSITY AND AREAL
COVERAGE THIS EVENING AS THE MID LEVEL TO SFC SYSTEM
INTENSIFIES....INCREASING THE SLY LOW LEVEL FLOW ACRS THE MID ATL.
  
WHILE THIS SYSTEM WL BE FAIRLY PROGRESSIVE...MDT TO HVY PCPN STILL
A
GOOD BET GIVEN THE AMPLIFYING NATURE OF THIS SYSTEM.    ATTM...DAY
1
PROG IS FAIRLY CLOSE TO MODEL QPF...INDICATING .50-1"+ MAX AMTS
ACRS
SERN PA...CNTRL TO SRN NJ AND DE.  HEAVY SNOWS LIKELY ACRS MOST OF
SERN PA...EWD INTO NCNTRL NJ.  ATTM...IT APPEARS THE HEAVIEST
SNOWS
WL FALL TO THE SOUTH OF NYC ACRS SCNTRL PA EWD INTO CNTRL NJ. 
HOWEVER...SNOWFALL TOTALS MAY STILL EXCEED 4" ACRS THE NYC METRO
AREA...ESPECIALLY THE SRN PORTIONS.  SEE LATEST NFDQPFHSD FOR
FURTHER DETAILS.

SRN PLAINS...

CONFIDENCE IS NOT GREAT WITH PLACEMENT OF QPF ACRS THE SRN PLAINS
ALONG AN EXPECTED W-E FRONTAL BNDRY.  THE GFS AND RSM SREF
MEMBERS ARE WETTER THAN THE ETA AND ETA SREF MEMBERS.  TRENDED
TOWARD THE WETTER SOLNS OF THE GFS AND RSM SREF AS THIS FRONT WL
BE ALONG THE SRN EDGE OF THE WLYS WHERE  BOTH THE ETA AND GFS
SHOW PW CONCENTRATING ALONG THE FRONT.  DAY 1 PROG IS ONLY
DEPICTING .25" MAX AMTS OVR SERN OK/FAR SWRN AR...BUT LOCALLY
HEAVIER AMTS ARE POSSIBLE.  

S TX...

MODELS ARE ALSO SHOWING LARGE SPREADS WITH QPF POTENTIAL OVR
SRN TX DAY 1.  THE GFS AND RSM SREF MEMBERS ARE ALSO MUCH WETTER
HERE THAN THE ETA OR ETA SREF MEMBERS AS POINTS FARTHER NORTH.  
DAY 1 QPF BACKED OFF FROM GFS HEAVIER AMTS GIVEN VERY LOW
CONFIDENCE IN PCPN BREAK OUTS HERE IN THE ABSENCE OF ANY HT FALLS.
 

PAC NW/NRN ROCKIES...

THE STRONG PAC FRONT MOVG INTO THE NW THIS AFTERNOON WL CONT TO
PUSH QUICKLY EWD ACRS THE NRN ROCKIES TONIGHT AND INTO THE NRN
PLAINS FRI.   IN THE WAKE OF THE MAIN FRONTAL BAND PCPN...STRONG
WSWLY ONSHORE FLOW WL PERSIST THRU THE PAC NW AND INTO THE NRN
ROCKIES.  THIS SHOULD SUPPORT MDT TO LOCALLY HVY PCPN AMTS OVR
THE FAVORED TERRAIN OF THE WA CASCADES...OLYMPIC RANGE...COAST
RANGE OF WA AND HIGHER TERRAIN OF NRN ID AND NWRN MT.

NRN PLAINS/UPR MS VALLEY...

LITTLE IF ANY PCPN EXPECTED ALONG THE ABOVE MENTIONED PAC FRONT
AS IT PUSHES QUICKLY EWD ALONG THE NRN TIER OF THE U.S. DAY 1.  
STRONGEST ISENTROPIC LIFT WL REMAIN TO THE NORTH OF THE U.S./CAN
BORDER...WITH AT BEST A HUNDREDTH OR TWO SKIRTING FAR NRN ND...NRN
MN AND THE U.P. OF MI.  


DAY 2...                 

...UPR/MID MS VLY/GRTLKS/OH VLY/TN VLY...
AREA OF SFC LOW PRES IN SERN CAN WILL MOV NEWD.  CDFNT WILL
EXTEND SWF FROM THIS LOW ACRS THE GRTLKS AND MS/OH VLYS.  AT
H5...TROF MOVS OVER THER ERN CONUS.  THERE IS SOME STRONG UVV
OVER THE GRTLKS ERLY IN THE PD AND ACRS THE TN VLY TWD THE END
OF THE PD.  UPR JET SUPPORT IS QUITE STRONG ACRS THE NRN TIER
WITH 110 TO 10 KT JET ALG THE BASE OF THE TROF.  H8 FLOW IS
INITIALLY
RELATIVELY WK...BUT STRENGTHENS TO 30 TO 40 KTS FROM THE SW.    BY
THE END OF THE PD IT BECOMES MORE WLY IN THE CNTRL PLAINS AND
MIDWEST.  PWS INCREASE TO AOA 1.25 INCHES ACRS SRN MO...NRN
AR...THE MS VLY AND INTO KY AND TN.  

MDLS ARE FAIRLY CONSISTENT OVERALL IN THEIR SOLNS.  THE ETA AND
UKMET ARE IN VERY GOOD AGREEMENT WITH THEIR QPF.  THE CAN HAS
THE AXIS IN THE SAME PLACE AS THE ETA/UKMET BUT HAS LESS AMTS. 
THE GFS IS FURTHER N WITH ITS AXIS AND IS THE OUTLIER.  IT ALSO
KEEPS
MORE PRECIP IN THE COLD SECTOR.  THE ETA ALSO GENLY HANDLES
COLD AIR BETER.  A BLEND OF THE ETA/UKMET IS SUGGESTED.

ORAVEC/NIERENBERG

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 
24HR QP VT 20/00Z
 0.01 470912 483974 487011 491035 500053 513072 529079 543068 
      552058 558027 555952 535870 520848 513840 505834 495828 
      486824 477823 473823 467825 463830 460835 458841 458849 
      459857 461865 463881 470912 
 0.01 542198 540187 536179 528167 518155 513149 509147 501141 
      496136 487128 481124 473120 460125 455130 451137 450144 
      447154 443162 444167 446170 446174 445179 440182 440186 
      443189 448194 452197 454196 456193 461186 464179 463175 
      461173 459170 460168 466170 474174 480177 485182 496191 
      500192 504193 510198 518210 523217 529220 532219 536216 
      539212 
 0.01 522266 524255 522245 520240 512226 506212 498201 490198 
      487198 484200 478200 473202 468205 462206 457209 452210 
      440214 435216 431220 429225 430227 432230 444232 446233 
      444235 442240 442243 444248 445249 455252 470258 474260 
      480264 486269 491275 494279 498284 501287 505289 510288 
      514284 518278 
 0.01 423817 421761 425743 434735 447732 460723 467711 468700 
      457697 448701 438704 433704 428699 425690 407671 388673 
      376682 358716 346752 343766 340769 339776 337791 338798 
      341799 345798 353794 358788 363781 367778 371777 373777 
      375781 377791 376797 372802 367807 363810 360814 349823 
      347827 347831 346840 347845 350844 357840 366837 373838 
      379841 384843 391845 404844 412840 417835 419830 420825 
      423817 
 0.01 459081 459079 457076 456075 453072 450071 447071 445072 
      446076 447079 449080 450082 452084 453085 456086 459085 
      459084 459081 
 0.01 367968 367960 366952 364937 360924 358917 356914 352909 
      347906 344905 337905 329902 323904 320907 318912 319919 
      322929 323937 326941 330954 331959 333966 335981 336996 
      338004 340007 343011 347014 353014 356012 360007 362002 
      364990 367977 367968 
 0.01 304978 304970 301966 297964 294965 287966 275967 265965 
      258964 252966 247969 246974 248981 250985 254989 257992 
      266997 271999 277999 284999 291997 295993 298990 303980 
      304978 
 0.25 547984 541947 535926 527918 519918 514924 515940 516947 
      525982 533003 540018 546014 548992 547984 
 0.25 517263 517256 515248 510236 500214 496207 490204 480205 
      470210 461215 456216 453217 454220 456223 462226 467225 
      472224 477223 483224 488229 491234 491239 484238 481236 
      480234 477229 468231 464232 462236 462241 465244 471248 
      476251 481255 486259 489263 499273 502276 505276 509273 
      513270 516266 517263 
 0.25 524192 524187 523184 520177 512166 507161 502157 497153 
      495144 492139 488134 482130 478128 474127 472130 472133 
      473138 476140 483142 486147 488153 489158 488164 488169 
      489171 496176 501179 507183 511188 516192 519194 523193 
      524192 
 0.25 414690 411684 406682 402686 398691 391703 385715 375724 
      369733 365746 364752 366758 370761 375763 384765 390768 
      392772 393776 393791 392798 393803 395807 399808 403806 
      408800 411794 415782 415766 412751 411743 412735 412722 
      415694 414690 
 0.25 475159 474154 473154 471150 470149 468145 465145 462147 
      462148 461152 462153 464157 467159 470160 473160 475159 
 0.25 349964 350957 350950 348944 346937 344934 341932 337932 
      335936 335943 337949 339956 340959 342966 344969 347968 
      349964 
 0.50 509255 511250 510246 509240 505230 500219 498213 494209 
      488208 482209 479209 474211 471215 473218 475219 481220 
      487223 490225 493230 499241 503251 506254 509255 
 0.50 496264 496259 494252 492247 489243 485241 482240 479235 
      476231 473233 470237 469240 474246 477248 482252 485255 
      490259 493263 496264 
 0.50 486139 486138 484134 483133 480134 482138 484140 486139 
      486139 
 0.50 409702 407698 404696 400698 398702 394711 393715 390719 
      384726 380734 379751 385756 395760 398768 401779 402786 
      406786 409782 410774 409754 407742 407721 409713 410704 
      409702 
 1.00 496214 484212 482214 483215 488217 490221 495230 498233 
      501235 500231 499227 499223 497218 496214 
 1.00 387737 390746 393750 399756 401752 402749 400740 400735 
      399731 396728 393727 391730 390732 389733 387737  
 
24HR QP VT 21/00Z
 0.01 546762 544750 540739 538729 534720 528699 524689 521685 
      517681 512679 502672 496670 490671 480673 475673 469678 
      460687 449698 443703 437707 435706 432701 429697 426694 
      425695 424699 425703 425730 424738 421741 418744 413747 
      414751 423757 427760 431766 431771 430774 425779 415784 
      409783 405782 399780 393781 383790 375798 372802 369808 
      366813 364819 361824 358826 354826 347827 345827 343826 
      344824 347819 348815 345811 337807 327804 317805 306808 
      302810 298815 294820 296828 302841 304846 305849 308852 
      312855 315860 321869 329876 336884 338889 341893 344902 
      344910 342915 341922 339949 340958 342966 345970 349972 
      353971 356965 362955 373936 379926 386916 393906 396904 
      399904 403905 408907 412911 416914 424914 436913 441910 
      445906 449901 451898 453897 457900 462915 464922 468930 
      472941 475948 477956 480962 483967 487968 490967 496964 
      502963 508959 513954 514948 514942 516937 518930 521926 
      525927 530929 540930 545926 549920 554908 556900 557889 
      557881 555866 553854 553844 553837 553830 553823 551814 
      550805 547788 546762 
 0.01 527184 529177 528173 522164 517159 511156 507154 503154 
      497156 495160 495167 496176 500183 507188 514194 518193 
      521192 527184 527184 
 0.01 505258 506254 505248 502243 499238 497234 495230 489225 
      486225 483226 482231 482236 484244 486249 488253 491257 
      495262 498263 501261 505258 
 0.01 342079 340072 342065 342060 341056 338051 335045 332035 
      332031 332028 329028 324032 321039 310039 305042 302049 
      303059 304064 306065 320068 327071 328074 328078 330086 
      334087 338085 342079 
 0.25 530776 532771 533769 534765 533761 532759 515725 504716 
      501715 496717 493721 490727 485731 481729 477730 473734 
      468739 461746 457753 454761 452770 452779 453787 455800 
      456809 459820 465820 471819 478820 484823 491826 496829 
      503835 507838 511846 516857 521865 523867 526868 529863 
      530853 531850 535844 535824 534816 531810 527803 527787 
      530776 
 0.25 397805 393802 388801 384805 380812 368833 364839 361842 
      358844 344850 341855 342861 349873 351882 352891 353907 
      352914 351920 351929 354937 358937 361935 364929 368917 
      373912 376907 384895 389883 395872 397864 397855 397848 
      394838 394830 396822 397805 397805 
 0.50 380843 377840 371843 364853 361856 356855 352855 350857 
      351865 356878 356892 357906 360910 367910 372906 375901 
      377896 377886 377871 379859 380844 380843  
 
$$