FXUS04 KWBC 200659 PAA
QPFPFD

 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
158 AM EST SAT NOV 20 2004
 
PRELIM DAY 1 AND DAY 2 QPF DISCUSSION
VALID NOV 21/1200 UTC THRU NOV 22/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 
...DAY 1...

THE WORD OF THE DAY IS BLEND. 


...NORTHEAST AND SOUTHEAST...

SHRTWV ENERGY IS FCST TO SLOWLY BREAK DOWN THE UPPER RIDGE
CURRENTLY OVR THE ERN U.S. AND AS A RESULT TRIGGER AREAS OF LGT
AND SCTD WAA PCPN.   LOTS OF MINOR DIFFERENCES BTWN MODEL MASS
FIELD FCSTS HERE THAT ARE DIFFICULT TO RESOLVE AND THAT ARE
LEADING TO QPFS THAT ARE ALSO DIFFERENT ESPECIALLY CONCERNING
AMTS.  WHEN ALL IS SAID AND DONE BASICALLY BLENDED THE MODEL
QPFS ACROSS THIS RATHER LARGE AREA.

...CONCERNING THE EVOLVING GREAT BASIN CLOSED UPPER LOW...

NOT A LOT OF DIFFERENCE BTWN MODELS CONCERNING THIS SYSTEM AS
WELL AS THE ACCOMPANYING QPF OVR THE SRN GREAT BASIN AND
CNTRL ROCKIES.   THERE WERE HOWEVER DIFFERENCES WITH QPF
DETAILS OVR THE SRN AND CNTRL PLAINS WHERE MSTR WILL BE TAPPED
BY SHRTWV ENERGY BEING EJECTED AHEAD OF THE CLOSING OFF
SYSTEM.   IN GNRL THE GFS IS MORE AGGRESSIVE WITH AMTS AND
COVERAGE HERE AND AGAIN IT IS DIFFICULT TO PICK AND CHOOSE BTWN
THE TWO.  AGAIN...ACCEPTED A BLEND BTWN SOLUTIONS EMPLOYING YE
OLDE BROAD BRUSH TECHNIQUE TO SMOOTH OUT DETAILS...ESPECIALLY
OVR THE SRN PLAINS WHERE THE OVRRNG OF AN OLD FRONTAL ZONE
SHOULD PRODUCE MORE ORGANIZED SHWR ACTVTY.

...GULF STATES/TN VLY...

MODELS RUNS CONTINUE TO HAVE STG CONTINUITY AND HIT THIS AREA
HARD WITH THEIR QPFS TODAY BUT AGAIN THERE ARE DIFFERENCES
WITH DETAILS.  FOR THE MOST  PART THE MODELS AGREE WITH TIMING
IMPULSES EMBEDDED IN THE SRN STREAM.  THE PROBLEM HOWEVER IS
THAT THE ETA IS A LITTLE QUICKER TO AMPLIFY THE UPPER FLOW AS
COMPARED TO THE GFS RESULTING IN ITS QPF BEING FARTHER NORTH OF
THE GFS QPF PARTICULARLY ACROSS THE TN VLY AS THE LVL WINDS
TAKE ON A STGR SLY WIND COMPONENT.   AGAIN HAVE LITTLE
CONFIDENCE IN PICKING AND CHOOSING BTWN THE QPFS OVR THE TN
VLY AND AGAIN OPTED TO BLEND THE PCPN AMTS AND COVERAGE THERE. 
MEANWHILE LATE IN THE PD...BOTH MODELS INDC THE REDVLP OF SGFNT
SHWR ACTVTY OVR ERN TX BUT THE GFS IS MUCH FARTHER NORTH OF
THE ETA WITH ITS PLACEMENT OF THE BREAKOUT.  AT FIRST GLANCE IT
WOULD APPEAR THAT THE ETA HAS THE BETTER HANDLE OF THIS ACTVTY
WITH THE GFS APPEARING TO HAVE SOME FEEDBACK ISSUES.  IT IS ALSO 
DIFFICULT TO UNDERSTAND WHY THE GFS WOULD DRIVE THE PCPN THAT
FAR NORTH AS THICKNESS SATURATION CRITERIA CHANGES LITTLE FM
WHAT IS CURRENTLY IN PLACE ALONG THE WRN GULF COAST WHERE
SHWRS ARE CURRENTLY CONFINED.
 
DAY 2...

...PAC NW/NRN GREAT BASIN...

SHRTWV CENTERED OVER NRN BRITISH COLUMBIA AT THE ONSET OF THE
PERIOD WILL DROP SEWD INTO CTRL CANADA.  ONSHORE FLOW ALONG
THE ASSOCIATED SFC FRONT DROPPING S THRU THE PAC NW/NRN GREAT
BASIN WILL FUEL GENERALLY LIGHT PCPN MAINLY ACROSS THE FAVORED
TERRAIN.  DESPITE THE ETA BEING SIGNIFICANTLY FASTER THAN THE GFS
TO PUSH THE COLD FRONT THRU...QPF DIFFERENCES WERE RELATIVELY
SMALL.  WITH THE ETA A RELATIVE OUTLIER IN COMPARISON TO THE
OTHER MODELS...WHERE DIFFERENCES WERE NOTED LEANED CLOSER TO
THE GFS.

...SOUTHWEST/CTRL GREAT BASIN/NRN AND CTRL ROCKIES...

UPR LOW CENTERED OVER SRN NV AT THE END OF DAY ONE WILL SETTLE
INTO THE DESERT SW THIS PERIOD.  DEEP MOISTURE ADVECTION FROM
THE ERN PAC...ACROSS THE GULF OF CA AND INTO THE SWRN
U.S....COMBINED WITH PRONOUNCED UPR LVL DIFFLUENCE DOWNSTREAM
OF THE CTR AND FAVORABLE OROGRAPHICS...SHOULD PROMPT
WIDESPREAD PCPN FROM CTRL AZ...ACROSS THE FOUR CORNERS REGION
AND INTO THE CTRL/SRN ROCKIES.  HVY SNOWS ARE POSSIBLE ACROSS
SOME PORTIONS OF THE HIER TERRAIN.  REFER TO THE QPFHSD FOR
FURTHER DETAILS.  PREFERRED THE GFS SOLUTION HERE...WHICH FALLS
BETWEEN THE SLOWER UKMET/CAN GLOBAL AND THE MORE
PROGRESSIVE ETA.

...SRN PLAINS TO THE SOUTHEAST...

SFC BNDRY AND A COINCIDING POOL OF DEEP MOISTURE...STRETCHED E-
W ACROSS THE REGION WILL REMAIN AN ACTIVE FOCUS FOR MDT/LOCALLY
HVY PCPN.  SWLY FLOW DOWNSTREAM OF THE UPR LOW IN THE W
SHOULD GRADUALLY PUSH THE WRN EXTENT OF THE FRONT NWD THRU
TX.  IN ADDITION TO ENHANCED LOW LVL CONVERGENCE IN THE VCNTY OF
THE FRONT...SHRTWV ENERGY EJECTING OUT OF W...FAVORABLE UPR JET
DYNAMICS AND A DEEP OVERRUNNING MOISTURE PLUME SHOULD LEAD TO
A HVY RAINFALL EVENT ACROSS ERN TX LATER IN THE PERIOD.  THE ETA
WITH ITS FASTER SOLUTION IN THE W...DRAWS THE FRONT FURTHER N
THAN THE ETA.  GIVEN THE PREFERENCE FOR THE GFS
UPSTREAM...LEANED CLOSER TO ITS SOLUTION HERE AS WELL. 
HOWEVER...GIVEN WHAT APPEARS TO BE GRIDSCALE FEEDBACK
PROBLEMS IN THE GFS...DID NOT GO WITH ITS HEAVIEST AMTS. 

KORTY/PEREIRA

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 
24HR QP VT 21/12Z
 0.01 539208 539202 537194 533182 528169 523160 520157 514155 
      509156 505160 498164 496168 495172 495176 497181 500183 
      503188 507193 508198 508207 509213 508217 505216 503211 
      500210 497209 494209 492212 491217 492225 491232 491235 
      487238 484241 481240 478242 477246 479251 482254 483263 
      485268 488271 493276 495281 498285 503289 509290 512289 
 0.01 518906 516885 512866 502838 495824 491807 486769 485761 
      482753 477742 474715 471705 467700 464698 459697 440698 
      432696 424692 416688 410688 406686 399680 395677 390675 
      385677 381681 376692 373702 373712 374725 376733 375736 
      372737 362737 353739 346746 341756 339766 340778 341782 
      341786 340790 338794 333793 326795 321798 316798 314800 
      310806 304813 300822 297830 293838 290848 290857 291866 
      292881 292891 290901 286920 284942 283949 281954 277965 
      276974 273986 272992 274997 283002 286004 291002 294001 
      299998 304994 312990 315993 316997 318009 328028 335033 
      342032 345031 347033 347040 346045 345051 344059 344068 
      349075 350079 348083 349089 344090 340087 337083 334082 
      332084 332089 334115 338124 340129 345133 351134 357134 
      363134 370135 387145 391147 393146 393143 389134 387131 
      391127 394127 395129 399131 402128 406124 409126 415129 
      421129 428123 434120 440120 442125 445136 445143 442146 
      440148 439152 441157 447160 452158 455155 458148 459144 
      460138 457132 453127 452123 454119 458114 464110 466102 
      465097 460093 456088 455083 455074 451069 448067 442066 
      432070 430067 430062 429049 426039 423032 420027 415018 
      404999 401993 398990 391983 383978 379974 376970 370958 
      364949 358942 354936 352930 352922 354912 358891 361879 
      364868 371848 373838 371831 367828 368822 370817 375815 
      379815 387813 392813 397814 399817 398820 399832 395842 
      390854 388860 385864 383869 383872 384880 389880 394879 
      399877 408876 417870 423867 429865 435863 441863 443868 
      440872 437878 435884 434891 436898 443906 446908 454908 
      463910 471913 478919 481923 484928 489939 493946 497949 
      500951 504952 507951 511946 514941 516932 517921 518906 
 0.01 362832 362828 358826 355820 357813 356810 355805 349808 
      344808 341810 342818 345824 348828 350833 354836 356832 
      355830 360833 362832 
 0.25 532219 534215 534210 534205 533204 533200 531196 530194 
      529192 526189 523188 520188 518191 518196 519201 520206 
      521210 521211 523215 526217 527218 529219 532220 532219 
 0.25 511280 513276 515272 516267 515262 514258 514257 512253 
      509252 507254 505258 502261 501261 499261 495262 494263 
      493267 494269 497272 497274 499276 502279 504281 507281 
      511280 511280 
 0.25 455760 454751 450742 444734 439731 434730 426730 421728 
      420721 414716 405710 397707 391706 387708 385714 384719 
      385723 388726 392729 394737 397744 401748 406751 415754 
      423758 428759 432761 435765 438774 443790 447793 452796 
      460799 459784 460781 459777 459772 457768 455760 
 0.25 416064 415059 412053 406045 398038 392031 388026 383022 
      376015 373011 368010 367022 369032 361048 360056 365065 
      368071 368081 366086 363089 356099 355106 357112 364113 
      370111 373108 377106 392091 406076 413070 416064 
 0.25 370000 371993 369986 365976 361969 355963 349964 346966 
      344970 342975 340986 339997 338007 340014 351012 359009 
      368004 370000 
 0.25 351869 350863 348859 343854 335842 331840 328841 325847 
      322854 316858 301882 298898 296913 293929 293938 291945 
      284975 285985 287989 290990 296989 301985 311974 316969 
      324966 327961 330952 333947 334939 340922 344910 348892 
      350876 351869 
 0.25 354120 355117 356114 354111 351112 350113 350117 351119 
      354120 354120 
 0.50 402061 403057 401055 399053 398052 395050 394050 392047 
      389047 387050 388053 389055 392056 394057 395059 396061 
      398062 401062 402061 
 0.50 396072 395068 392067 387069 381068 376066 373068 372075 
      372083 372091 372094 373097 376100 380097 383092 388087 
      392080 395074 396072 
 0.50 346874 344867 340861 336855 333854 329855 326862 323867 
      319868 315870 310883 306886 303891 300905 298918 296931 
      294945 291957 289971 291978 295979 299977 307970 317962 
      321958 324952 333928 338916 341904 346875 346874 
 0.50 355992 356988 355984 354984 353985 351987 351989 350992 
      350996 352996 353995 355992 355992 
 1.00 339880 337873 336871 333872 331876 326878 323878 321881 
      319885 315892 310900 305906 302916 301924 300937 298944 
      295955 295961 297967 302968 305965 312960 319953 321946 
      327927 333909 336899 338891 339880 
 1.50 332892 331889 328890 323892 321895 318897 316900 314904 
      310915 306922 304928 303936 302943 299950 300956 304960 
      309957 314953 318946 321932 324925 325918 329906 332892 
 2.00 322912 321908 318910 316915 314921 310927 307932 306939 
      307945 309948 311948 315941 315934 318926 320919 322913 
      322912  
 
24HR QP VT 22/12Z
 0.01 493658 483649 477647 471648 464649 460652 447658 440664 
      436669 431677 430683 431691 434695 434699 432703 427708 
      420713 414716 408717 401722 395728 396733 398737 404739 
      410740 414742 416746 419748 423754 428755 433760 437761 
      441758 444753 448750 452748 457745 463741 467735 468728 
      468719 467714 467710 472704 476697 482681 485677 489677 
      491675 493658 
 0.01 539207 540192 535181 531170 525163 522158 518153 515150 
      510148 502144 495138 489129 482123 478120 476115 475111 
      473104 470102 464101 459100 456097 452093 449092 441093 
      438097 437100 438104 441112 444115 449117 452120 453126 
      448152 449158 449164 445174 441182 439188 440195 442203 
      448204 450200 454189 462187 472171 476172 478177 484186 
      489186 494189 496194 499197 507202 510207 512212 515217 
      517219 522223 528223 533222 536218 539207 
 0.01 521270 522263 522257 520249 516243 515236 513228 511224 
      508221 504216 503210 496204 493199 489195 484196 478200 
      472201 468205 466206 462205 452212 443216 440220 441224 
      447228 451225 455227 453230 443234 443239 447245 451246 
      455246 459245 466247 471250 474252 478253 481258 485273 
      488282 491288 497292 505294 509291 513286 517278 
 0.01 427060 423056 418053 414047 409042 402034 396023 389012 
      381998 378992 375989 365984 361981 359977 358974 358967 
      360959 361952 359944 357938 354932 352925 347918 344913 
      343906 347895 351885 352879 356871 359858 362832 362826 
      361817 358800 354792 351786 345776 332776 328762 325754 
      324751 321750 313747 309749 307753 304757 301763 301772 
      302783 302793 298806 296812 296819 295830 295844 296850 
      295857 293869 289891 286898 283903 276912 265929 259954 
      259960 260966 260974 261981 264986 265995 270005 276015 
      283022 290030 299037 309043 318046 324050 327051 328055 
      327063 325070 322075 319078 313085 307089 303091 297095 
      294101 293109 295116 300126 303129 307136 312147 321151 
      327153 331154 335153 345148 357144 364146 368148 374151 
      377153 382159 385165 392167 396166 398165 403159 406157 
      409152 408148 405140 404137 404131 409118 412111 412105 
      412091 415080 418072 421068 424065 427060 
 0.25 534210 537201 536191 530183 522173 511170 507168 502167 
      495171 496176 500182 506188 511191 514195 517200 520206 
      522211 526215 531214 534210 
 0.25 515272 517267 518261 516255 514249 511242 509235 505231 
      499220 493211 490208 486207 480207 475208 471211 467215 
      466217 466220 477219 483221 490221 499246 501252 496250 
      493248 486245 481240 479234 477232 474231 472232 471236 
      473242 479246 485246 488253 492266 495272 498278 502283 
      507283 511280 515273 515272 
 0.25 404083 404078 403076 397073 393068 388065 383061 379056 
      375053 369050 363051 357053 354058 358065 365074 366078 
      366084 364090 361093 358095 354095 351093 344084 338079 
      334077 328078 324084 319096 318101 319106 322111 339126 
      348130 355130 362128 368125 376126 381122 385117 391113 
      394108 400094 403087 404083 
 0.25 344821 343812 340804 337799 334795 330791 325789 319790 
      318793 315806 312816 309838 308862 306874 304884 299895 
      294903 290911 286921 282932 280943 279954 279966 278981 
      278986 279993 283000 288003 294005 306006 311006 318004 
      325999 332989 337980 342970 344958 344950 342942 338928 
      333918 330913 328907 326899 326891 327886 330881 335872 
      340862 343851 344843 345835 344821 
 0.50 517263 517262 514259 512256 511255 509252 508255 508259 
      508260 510264 513265 516263 517263 
 0.50 507278 506273 506272 504267 504266 501263 498264 498265 
      498269 500273 500275 502278 505279 507278 
 0.50 480210 478211 475213 474215 475216 478216 482214 483211 
      482209 480210 
 0.50 398087 398083 395082 387081 382075 378070 374068 376071 
      376075 375083 372093 372099 373102 377103 383100 389096 
      395091 398087 
 0.50 339834 337826 334818 331808 325799 322809 319815 317821 
      317827 319835 319840 318845 317853 318859 320864 323865 
      326864 330861 333857 336851 338845 339834 
 0.50 360121 361116 360112 354109 349104 346099 343092 338088 
      334087 332088 330093 330098 333105 336112 340118 345123 
      351126 357124 360121 
 0.50 336950 335939 333933 330926 326920 322914 319906 317890 
      318872 317866 312867 311882 309889 306893 299905 295910 
      293916 289930 289937 290942 296945 304945 305950 303957