QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
254 AM EDT WED MAY 06 2009
 
 
PRELIM DAY 1 QPF DISCUSSION
VALID MAY 06/1200 UTC THRU MAY 07/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 
 
DAY 1...

LOWER MS VALLEY...TN VALLEY......OH VALLEY...SRN TO CNTRL
APPALACHIANS..MID ATL INTO THE NORTHEAST...

ANOTHER WIDESPREAD HEAVY TO LOCALLY EXCESSIVE PCPN EVENT ON TAP
DAY 1 AS THE NEXT IN CURRENT SERIES OF SRN STREAM SHRTWVS MOVES
NEWD FROM THE SRN PLAINS TOWARD THE NORTHEAST.  WELL DEFINED MID
TO UPR LEVEL DYNAMICS MOVG ALONG THE AXIS OF MUCH ABOVE NORMAL PWS
WL FAVOR WIDESPREAD 1"+ PCPN AMTS ACRS THESE AREAS.  LOW LEVEL WLY
FLOW FROM PORTIONS OF THE LOWER MS VALLEY...EWD ACRS NRN GULF
COASTAL STATES WL SUPPORT POTENTIAL FOR TRAINING OF PCPN IN A W TO
E DIRECTION.  THIS WL LIKELY BE THE AREA OF HEAVIEST PCPN AMTS DAY
1.  AREAL AVG 2"+ AMTS DEPICTED WITH POTENTIAL FOR TOTALS OVER 5"
WHERE TRAINING OCCURS.  THE GFS IS SHOWING SOME GRID SCALE
CONVECTIVE BULLS EYES OVR NRN MS..NRN AL AND NRN GA...INDICATING
THE HEAVY RAIN POTENTIAL.  WHILE THE GFS BULLSEYE DEPICTIONS ARE
LIKELY NOT CORRECT...THE MAX TOTALS OF 4-6"+ MAY BE REASONABLE FOR
MAX AMTS WHERE TRAINING PERSISTS DAY 1 INVOF NRN MS...NRN AL AND
INTO NRN GA. 

THERE STILL IS SOME UNCERTAINTIES FARTHER TO THE NORTH AS TO THE
AMT OF PCPN THAT SPREADS NEWD INTO THE MID TO UPR OH VALLEY AND
TOWARD THE ERN LAKES.  THE NAM AND MANY OF THE NAM SREF MEMBERS
ARE THE FARTHEST TO THE NW WITH HVY PCPN AMTS FROM THE MID OH
VALLEY NEWD INTO THE ERN LAKES.  THE GFS...ECMWF...UKMET AND CMC
ALL FAVOR A FARTHER EWD QPF AXIS FROM THE TN VALLEY...ERN OH
VALLEY AND INTO THE NRN MID ATL AND NOT AS HEAVY AS THE NAM.  THE
NAM IS NOT AS HEAVY WITH QPF FARTHER TO THE SOUTH ACRS THE LOWER
MS VALLEY INTO THE NRN GULF COAST STATES AND MAY BE BRINGING TOO
MUCH PCPN NEWD.  DAY 1 QPF TRENDED MORE TOWARD THE GFS/ECMWF IDEA
HERE AS WE FAVOR HEAVIER CONVECTIVE TOTALS FARTHER TO THE SOUTH. 
AREAL AVG .50-1"+ AMTS FAVORED IN THE FARTHER EWD AXIS.

UPR MS VALLEY TOWARD THE WRN LAKES...

ADDITIONAL NRN STREAM SHRTWV ENERGY FCST TO MOVE INTO THE NRN HIGH
PLAINS ON WED AND TOWARD THE UPR MS VALLEY WED NIGHT/EARLY THU. 
THIS WL SUPPORT SCT CONVECTIVE ACTIVITY...MOSTLY OVR THE UPR MS
VALLEY INTO THE WRN LAKES WHERE PW VALUES ARE HIGHER IN ASSOC WITH
THE PREV AREA OF NRN STREAM HT FALLS THAT MOVED EWD INTO THE UPR
MS VALLEY YDY.  CONFIDENCE IS NOT GREAT WITH QPF AMTS ACRS THIS
AREA GIVEN THE LARGE SPREAD IN OPERATIONAL AND SREF AMTS.  AREAL
AVG .25-.50" AMTS DEPICTED WITH ISOLATED HEAVIER TOTALS POSSIBLE.

PAC NW INTO THE NRN ROCKIES...

A STREAM OF MID TO UPR LEVEL SHRTWV ENERGY EXPECTED TO PUSH NEWD
DAY 1 FROM THE MEAN NERN PAC TROF AND INLAND ACRS THE PAC NW/NRN
ROCKIES.  THESE HT FALLS WL SUPPORT PERSISTENT ONSHORE SWLY TO WLY
LOW LEVEL FLOW ACRS THESE AREAS DAY 1.  MDT TO HVY PCPN AMTS
LIKELY IN THE FAVORED TERRAIN REGIONS OF THE WA/OR CASCADES AND
WA/OR COAST RANGE AND OLYMPIC RANGE.  FOR QPF DETAILS THE 12 KM
NAM AND NAM SREF MEMBERS WERE USED...WITH .50-1"+ AREAL AVG PCPN
AMTS DEPICTED.  LIGHTER PCPN AMTS LIKELY INLAND FROM NERN OR...FAR
NERN WA...CNTRL TO NRN ID AND NWRN MT....WITH AREAL AVG .25"+ AMTS
DEPICTED.


ORAVEC

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 
24HR QP VT 07/12Z
 0.01 479619 476615 471609 467607 463606 455606 450607 445610 
      440611 434614 431615 426619 423623 420630 417638 406661 
      401669 397681 395691 395697 398703 401706 407707 409707 
      408709 407713 400725 393733 385739 374747 364753 354760 
      346768 340775 333783 329792 324800 320810 313827 310835 
      307846 301864 296883 295892 294900 295906 293914 292919 
      293926 296940 299950 303961 307969 314976 320982 324984 
      330982 334978 336975 341966 345956 349948 352939 353936 
      353932 355928 360920 366911 372904 394869 403850 410830 
      416820 421810 424805 426802 432799 437794 443785 449774 
      456764 459761 463755 468744 471732 474709 477702 481696 
      485685 488673 488667 488658 487647 484637 479619 
 0.01 534205 535187 533180 528170 523163 518157 511150 498139 
      491131 485125 472117 476111 475108 473103 466100 460093 
      457083 452076 447072 441069 441073 445079 447081 450088 
      450093 448093 438092 432088 429086 424085 422090 424095 
      425099 422102 420109 420116 421122 423126 425130 428127 
      434120 439122 443129 444135 444138 442140 437137 433140 
      430146 430153 429165 417173 415176 415180 421185 418203 
      421212 418215 414212 408211 406208 401203 386246 391254 
      396260 402265 412268 416270 421270 428269 436270 443269 
      453269 460271 469271 477273 486275 491278 493281 495286 
      497287 499288 501289 506287 511281 514274 515267 516259 
      516250 514242 511233 507223 505218 506214 508211 512210 
      518217 522221 526218 530215 532211 534205 
 0.01 515931 515925 514918 511913 502903 496891 494885 492877 
      493872 493865 491855 490847 491839 490836 483836 470841 
      464840 460838 455835 450834 438832 431835 424839 420843 
      414849 411853 407859 405864 404869 401876 398883 396889 
      395895 393901 390907 385917 384924 384932 386940 389940 
      391938 394933 398936 409957 412967 414972 420983 424989 
      426997 431010 435024 436033 440040 442041 445040 448035 
      450029 450019 449008 449998 449988 446978 444962 445957 
      453954 456953 460954 465955 474961 478964 486963 491960 
      496955 500947 504944 507943 515931 
 0.25 470668 467659 462651 458647 453644 448643 443644 437647 
      431652 427658 426664 427680 428686 432690 443691 448692 
      452694 458696 461694 464690 467685 470679 470668 
 0.25 511260 512252 510242 504227 498211 493206 486203 480205 
      474207 468209 462210 450213 447214 443215 437214 430215 
      428216 425220 423232 415230 411230 410232 407238 406245 
      410251 415255 421257 427257 453256 465256 474256 478257 
      483260 488266 493272 499278 505277 505270 504260 505257 
      507258 511260 
 0.25 515185 514180 511175 505167 499164 493163 489161 485156 
      476151 471145 465144 462146 456153 438149 437157 439161 
      445170 448174 448177 444181 441186 444190 446191 449193 
      452192 455188 462180 463178 462175 460169 460168 463166 
      466167 472170 478171 497181 506185 512186 515185 
 0.25 452711 448704 443699 440697 436696 433698 424712 414725 
      402737 396742 388748 376757 368762 360767 348776 344781 
      340788 337796 336802 331816 322841 314853 312859 312866 
      314884 313890 314901 314917 313924 313931 314941 316947 
      319956 322963 324965 326966 331961 334957 338949 343936 
      347923 349915 352907 354901 359895 364891 369886 373881 
      378874 382870 385864 389857 392850 393841 393834 400827 
      404821 410810 414803 419797 424791 431783 435778 439770 
      447756 450750 453743 454734 453725 452711 
 0.25 473863 472858 470855 466852 461850 454850 442851 434853 
      428856 425860 426862 430867 429869 425874 415882 408891 
      406897 407901 410910 415924 421939 424945 425949 424954 
      427961 433964 433962 429957 427951 426947 427941 430937 
      433932 436915 438902 441896 445891 454883 460877 465875 
      471869 473863 
 0.25 445113 446109 444105 444104 441102 438104 438105 438108 
      441110 443113 445113 
 0.50 509250 506239 503232 498213 495210 491209 483208 477209 
      470211 464212 456215 449216 443217 430221 429225 431228 
      435233 434237 430239 426243 429248 435247 450250 465250 
      473251 482253 485256 490262 494269 498273 500273 503271 
      500261 497253 494244 490238 486236 484237 481231 474225 
      478223 482223 487226 491232 496239 500244 505251 509250 
 0.50 448737 448731 446726 441723 430723 424724 417729 407739 
      400746 397749 383758 373766 360773 357774 352780 345790 
      336813 332824 328836 322859 319872 318885 317900 318913 
      317928 319935 321941 325948 329949 333946 337939 341928 
      345917 349904 352899 355894 372876 380866 383860 385853 
      385840 383834 385829 397821 400816 402811 410798 418788 
      422782 428776 435767 445751 447743 448737 
 0.50 440884 439879 435879 430880 424882 419888 416892 415897 
      416903 418912 423918 428917 430914 432908 433899 435894 
      438890 440886 440884 
 1.00 495258 494255 493253 492249 491248 489245 486246 488251 
      488252 491255 492257 493259 495258 
 1.00 488219 489215 488214 485213 482212 479211 477212 476213 
      473214 472215 473216 475217 478218 481218 484219 487220 
      488219 
 1.00 479243 480239 479235 478234 476232 473232 470236 470240 
      472242 474244 477245 479243 
 1.00 432748 428746 420748 412753 404757 396763 392769 389769 
      390773 393773 396775 398780 400780 404778 413775 420769 
      425764 432757 433749 432748 
 1.00 465239 464236 461235 458235 455235 455236 452236 449237 
      448237 448239 451242 454242 457242 460241 463241 465239 
 1.00 466222 467218 466217 464216 462216 461216 458217 455217 
      453218 451221 448220 445219 443219 442221 441223 442224 
      445225 447224 448224 451222 454223 457224 459226 462226 
      463225 466222 466222 
 1.00 380855 376850 370848 365849 361850 357849 358839 358828 
      357823 351823 348824 344827 338834 334838 333844 329855 
      326869 323881 322888 322897 322912 322918 322927 325935 
      328937 331937 336931 338925 342914 347900 352889 354882 
      355875 358869 362870 367870 370869 375863 380855 
 1.50 354835 350833 340840 337849 335857 328875 326884 325888 
      326894 326918 325922 327928 329931 331930 336922 339915 
      345895 348887 349876 352854 353845 354835 
 2.00 347867 344857 342850 340851 339857 337862 333870 330879 
      329883 328889 330897 335908 339900 343890 345881 346870 
      347867