QUANTITATIVE PRECIPITATION FORECAST

 
 FXUS04 KWBC 152153
 QPFPFD
  
 QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
 NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
 552 PM EDT SUN MAR 15 2009
  
  
 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
 VALID MAR 16/0000 UTC THRU MAR 19/0000 UTC
 REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
  
  
 DAY 1...
 
 18Z UPDATE..
 HAVE EXPANDED 1 INCH AMOUNTS FROM THE LWR MS VALLEY NEWD INTO
 PARTS OF THE CAROLINAS IN RESPONSE TO RAPID EXPANSION OF POST
 FRONTAL RAINS/TSTRMS ACRS THE WRN GULF AS NEXT S/WV AND UPR LEVEL
 SPEED MAX APCHS FROM THE SRN PLAINS.  18Z NAM LOOKS QUITE DRY HERE
 WHILE 12Z ECMWF IS CONSIDERABLY WETTER AND SEEMS TO HAVE A BETTER
 HANDLE ON SHORT TERM RADAR TRENDS.   ELSEWHERE..NO MAJOR CHANGES
 WERE MADE.  
 
 NWRN U.S...
 
 NO BIG CHANGES EXPECTED TO THE LARGE SCALE FLOW PATTERN FROM THE
 NERN PAC INTO THE NWRN U.S. DAY 1.  FAST CYCLONIC MID TO UPR LEVEL
 FLOW WITH EMBEDDED SHRTWVS WL CONT FROM THE NERN PAC AND INLAND
 INTO THE PAC NW/NRN ROCKIES REGION THIS PERIOD.  THE SUSTAINED
 ONSHORE LOW TO MID LEVEL WSWLY FLOW WL SUPPORT ADDITIONAL MDT TO
 HVY PCPN AMTS OVR THE NWRN U.S....WITH OVERALL GOOD AGRMNT IN THE
 LATEST OPERATIONAL AND SREF GUIDANCE WITH PCPN DISTRIBUTIONS AND
 AMOUNTS.  HEAVIEST PCPN AMTS DAY 1 EXPECTED OVR NRN TO NWRN CA AND
 INTO CNTRL ID WHERE THE MOISTURE FLUX VALUES ARE EXPECTED TO BE IN
 THE 2 TO 3 STD ABOVE THE MEAN RANGE.  AREAL AVG 1-2"+ AMTS
 EXPECTED ACRS THESE AREAS...WITH ISOLATED 3"+ AMTS POSSIBLE OVR
 NWRN CA.  ELSEWHERE ACRS THE NWRN U.S...AREAL AVG .25-50"+ AMTS
 EXPECTED.
 
 CNTRL GULF COAST INTO THE SOUTHEAST AND SRN MID ATL...
 
 THE MID TO UPR LEVEL SWLY FLOW ACRS THE SERN TIER OF THE NATION WL
 KEEP WET CONDITIONS GOING FOR AT LEAST ONE MORE DAY. THIS SWLY
 FLOW WL CONT TO OVERRUN THE SW TO NORTHEAST ORIENTED FRONTAL BNDRY
 ACRS THE SERN U.S.  WITH PW VALUES REMAINING ABOVE NORMAL ALONG
 AND NORTH OF THE BNDRY...ADDITIONAL MDT TO HVY PCPN TOTALS LIKELY
 AS THE LAST SET OF SHRTWV ENERGY IN THE RECENT SWLY FLOW ALOFT
 PUSHES ENEWD.  THE QPF AXES AMONG THE LATEST OPERATIONAL GUIDANCE
 ARE FAIRLY CLOSE...WITH THE SLIGHTLY FARTHER SWD AXIS OF THE
 GFS/CMC GEM PREFERRED OVER THE FARTHER NWD AXES OF THE ECMWF AND
 CMC GLOBAL.  AREAL AVG .50-1"+ AMTS DEPICTED IN THIS AXIS DAY 1.
  
  
 DAYS 2 AND 3...
 
 ...SOUTHEAST AND MID-ATL STATES...
 
 A MODERATE AMT OF MODEL SPREAD REMAINS ON THE FORWARD PROGRESSION
 OF THE SEMI-SPLIT FLOW UPPER TROUGH PUSHING THROUGH THE
 SOUTHEAST/MID-ATL REGION ON MON NIGHT BEFORE THEN SLIDING OUT INTO
 THE ATLANTIC ON TUES. THE 12Z NAM/GFS SOLNS HAVE TRENDED
 SLOWER...AND TWD THE 00Z ECMWF REGARDING THE TIMING OF THIS ENERGY
 PUSHING OFFSHORE. GIVEN THE RELATIVELY GOOD CONTINUITY SEEN IN THE
 ECMWF OVER THE LAST DAY OR SO...HPC WILL LEAN TWD ITS SOLN. THE
 12Z NAM IN ITSELF WOULD NOT APPEAR TO BE TOO BAD IF IT WERE NOT
 ITS MID LVL DEFORMATION ZONE APPEARING SOMEWHAT OVERDONE OVER THE
 MID-ATL COASTAL PLAIN. THIS ALLOWS THE NAM TO BE NOTABLY
 WETTER...AND WHILE THERE ARE SOME ENSEMBLE MEMBER SUPPORT FOR THIS
 FROM THE 09Z SREF AND THE 06Z GEFS...THE MAJORITY OF THE SOLNS
 SUPPORT NOTHING MORE THAN LGT TO LOCALLY MDT RAIN ACRS THE COASTAL
 PLAIN. MUCH OF THE DEEP MOISTURE IS EXPECTED TO BE OFFSHORE...AND
 THE UPR LVL FORCING IS NOT EXPECTED TO BE STG ENOUGH OR LINGER
 LONG ENOUGH FOR ANYTHING TOO SIGNIFICANT.
 
 ...PAC NW AND NRN INTERMOUNTAIN WEST...
 
 A PERSISTENT AND DEEP LYR PAC ONSHORE FETCH INTO THE PAC NW AND
 SPREADING DOWNSTREAM INTO THE NRN INTER-MOUNTAIN WEST WILL TAPER
 DOWN SOMEWHAT OVER THE NEXT COUPLE OF DAYS AS UPPER LVL HEIGHTS
 BEGIN TO BUILD GRADUALLY OVER MUCH OF THE REGION. THIS WILL HELP
 SHIFT THE MAIN FOCUS OF SHRTWV ENERGY A LITTLE FARTHER NORTH AND
 MORE INTO BRITISH COLUMBIA. NEVERTHELESS...SUFFICIENT ONSHORE FLOW
 AND OROGRAPHIC FORCING WILL EXIST FOR AT LEAST MODERATELY HVY PCPN
 AMTS ACRS COASTAL OR/WA AND INTO THE CASCADES. HPC LEANED MORE
 CLOSELY TO TWD THE HIGHER-RES 00Z ECMWF FOR THIS SOLN...EXCEPT
 WITH AMTS ENHANCED SOMEWHAT OVER THE OLYMPICS AND CASCADES.
 
 ...NRN PLAINS TO GRT LAKES...
 
 SHRTWV DYNAMICS EJECTING OUT ACRS THE NRN PLAINS/SOUTH CENTRAL
 CANADA WILL INDUCE A WAVE OF LOW PRESSURE ALONG ESEWD ADVANCING
 COLD FRONT AND IS EXPECTED TO SLIDE THROUGH THE NRN TIER OF THE
 COUNTRY. GENERALLY AHEAD OF THIS BOUNDARY THERE WILL BE ENOUGH
 FORCING/LIFT TO PRODUCE SCATTERED SHOWERS FROM ND/SD EASTWARD INTO
 THE GRT LAKES AND THEN INTO THE OH VLY/NORTHEAST LATE IN THE PD.
 GIVEN A LACK OF LOW LVL MOISTURE DUE TO THE MASSIVE SURFACE RIDGE
 SPRAWLING FROM THE SRN PLAINS INTO THE SOUTHEAST...PCPN AMTS
 SHOULD BE QUITE LGT. HPC PREFERRED A NON-GFS CONSENSUS FOR
 QPF...LED BY THE 00Z ECMWF AND 12Z NAM QPF.
 
 ORAVEC/SULLIVAN/ORRISON
 
 GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 24HR QP VT 17/00Z
  0.01 535191 535181 534174 531170 523158 520154 516150 510144 
       498134 475116 476103 474095 474088 473085 469085 467093 
       464098 461097 456094 450092 442091 433089 428087 425089 
       425096 426100 424104 423107 422119 423127 424147 427155 
       432163 434171 434177 433184 430192 429198 427200 422197 
       417197 413199 410202 406206 402205 399201 392199 384194 
       381196 379200 380204 382206 387212 393217 396218 395221 
       388220 385217 381216 374213 370213 367217 366222 370228 
       373234 377241 379247 382252 386256 394259 403261 419265 
       436269 444270 452271 466274 474277 482281 488286 491289 
       494294 499301 504302 507299 515281 518269 520255 517231 
       518223 520218 523216 526216 530210 533204 535191 
  0.01 486196 487190 486183 483178 478172 472172 468174 467179 
       463187 458192 454197 450204 449210 450212 453210 456210 
       458206 460204 465205 468205 471204 478203 484199 486196 
  0.01 416766 415762 411758 406754 399751 393745 388736 385724 
       382716 379711 375705 373703 369704 360710 352714 347717 
       343718 335720 329726 324744 317758 311773 308783 308791 
       306800 304807 279865 268893 260906 253919 249926 247933 
       244948 242956 241965 240975 242978 247980 251987 252991 
       255993 259992 263991 269987 273981 278975 290963 295957 
       300953 311942 334918 345906 352893 367881 373874 376867 
       383850 385841 386832 387823 392814 401798 405789 409782 
       413776 415772 416766 
  0.25 514262 515256 514249 511238 507226 502215 498208 494205 
       489205 479207 470210 462211 455213 451215 446214 437214 
       424205 423209 423214 422218 419219 417216 403208 395201 
       389199 383200 385206 390213 398219 401222 400224 382222 
       380225 380229 382233 388243 394248 401252 413255 422256 
       437254 446254 458253 465255 475259 483266 490274 497282 
       501284 513265 514262 
  0.25 520196 522192 522187 521182 518180 515179 513180 512183 
       511184 512185 513190 514191 517195 518196 519196 520196 
  0.25 485232 484227 483226 480226 477225 474226 471227 469227 
       471228 474229 477229 479231 482234 485233 485232 
  0.25 487139 485134 480130 476127 472126 469127 463126 460128 
       455131 454137 454141 450145 446144 443142 439138 436135 
       433137 431142 430146 432155 435160 438163 445172 448178 
       447180 441183 440190 443194 446197 451194 454189 461181 
       462177 460169 464164 476160 478159 476155 473151 471145 
       471139 481137 487139 
  0.25 454114 452109 450105 450104 447101 444099 441098 438099 
       436100 435101 434104 432108 432112 435114 438115 440116 
       441117 443119 446119 449117 452115 454114 
  0.25 371752 368747 364741 356737 351735 346737 341741 337746 
       333756 330766 326776 322788 317807 314819 311830 303847 
       293867 285885 277904 278908 282914 284918 284922 283930 
       284938 286941 288941 295938 302933 309926 317917 324908 
       335892 339883 344871 358827 361817 362806 365781 370767 
       371757 371752 
  0.50 510255 510246 508238 503225 500216 499213 495210 488208 
       482209 459215 447218 439216 431216 427217 422222 420229 
       415228 416220 415215 411214 408214 403209 399206 393202 
       388201 386204 388207 392212 396216 402220 404223 403228 
       391225 385226 384231 388238 393243 397246 405250 412252 
       418252 424251 428249 439241 453244 465246 476252 484257 
       488262 498274 500276 502273 502267 501264 495251 491244 
       487240 484241 479233 476231 472232 467234 460232 456233 
       445236 441239 437238 435235 436231 438230 450226 454225 
       462227 468223 474221 478220 487222 499241 501246 505250 
       508256 510255 
  0.50 471154 468145 463141 459143 456148 450150 445147 442144 
       439141 436139 434140 433144 433148 433152 435156 438160 
       445166 450175 451178 453178 455176 455172 455168 456164 
       460160 468158 471154 
  0.50 448113 447109 444105 441103 439104 438106 437108 438110 
       441111 442113 443114 446114 448113 
  0.50 365759 364755 363752 358751 351750 347749 343753 339761 
       333779 325798 322808 320817 317827 314837 307853 298869 
       294877 291886 289897 292906 292910 293916 293927 294931 
       298931 304925 315910 327895 332888 335880 338869 342858 
       348841 352818 356799 358788 361778 365759 
  1.00 503238 503237 501233 500230 498227 497227 497232 499237 
       502239 503238 
  1.00 480239 479236 477234 476233 473237 475241 478242 480239 
  1.00 454159 453155 452155 450154 447152 444150 444149 442147 
       439145 439144 438144 436148 436152 438156 438157 441158 
       443160 446161 447162 449164 451163 452163 454159 
  1.00 425242 425238 424237 417233 413232 412229 414219 403213 
       394205 391204 390206 393212 398215 404219 406224 407228 
       405231 399228 391228 390232 392237 397242 403246 409248 
       417248 421246 425242 
  1.00 350793 350784 347783 342795 338805 335810 332815 328820 
       325824 321835 312857 313863 313872 313877 303897 308898 
       311902 317893 324886 328874 332865 337852 340842 343830 
       345818 346812 348805 350793 
  1.50 420241 419236 414234 411234 405234 402231 397230 394233 
       395237 400242 403244 406244 412245 417244 420241 
  1.50 401212 399211 397209 395207 394206 393206 394208 394210 
       396213 399213 401212 
  2.00 417240 416238 413236 410236 407236 404235 402233 399233 
       397234 398238 401240 403241 406242 409242 411242 412242 
       415241 417240  
  
 24HR QP VT 18/00Z
  0.01 524261 521256 520250 519244 517238 512228 508221 497205 
       489201 480200 475202 471203 468205 465206 462205 460202 
       456198 456193 458190 462187 465187 469187 476180 478180 
       481182 485185 500189 505191 510193 516202 518206 523209 
       527211 530209 533205 535199 534195 531190 529185 527179 
       527173 522163 513154 506146 503143 497141 490132 482125 
       476125 470127 468125 467121 466115 469113 472111 473107 
       470093 473085 479078 482070 484058 485046 488032 492018 
       495005 495001 494994 494989 496982 498971 500956 503943 
       501935 497930 496928 496925 502922 505920 509914 511909 
       515907 520900 524892 527882 527877 526872 524865 520865 
       518868 512878 509883 506888 501892 496894 491894 488892 
       486888 487882 488876 492866 498852 504843 511833 517823 
       518818 517810 515804 512802 506800 502801 498803 493807 
       490812 486821 481829 478834 475837 471837 467833 460827 
       456826 453829 452835 455839 458843 460846 460851 458856 
       453862 448863 445864 442867 446874 449876 454874 458871 
       463871 465872 466878 467889 464903 464915 465924 466932 
       470945 468950 468957 469966 472974 473977 474985 471995 
       468002 466011 462022 461029 461038 459052 457062 453068 
       447068 444067 442067 439068 437071 437075 440080 441085 
       438089 432089 429088 426089 425093 426096 427100 423103 
       420106 418111 414112 409112 405113 404115 404119 405122 
       415122 420122 421127 422132 425131 432123 435120 439119 
       442121 444124 447127 452128 450136 448142 444143 439141 
       434144 432148 432155 432160 427162 424165 421169 415174 
       414181 416185 417189 423192 427194 430193 433188 436173 
       439170 441169 443174 444178 441180 438187 437193 438196 
       441204 445205 448199 449200 448209 446212 443212 440214 
       437214 434214 432216 427219 422229 417232 416229 417221 
       416217 414211 409211 405209 402206 395203 390206 391209 
       394214 401220 404224 405231 401235 399237 398238 399243 
       402246 407248 412249 414253 418260 420262 423266 425267 
       431269 437271 441272 447271 453267 462263 472264 479267 
       485272 489279 497292 503298 506299 510299 
  0.01 467132 469128 466125 465127 464131 466132 467132 
  0.01 419765 418759 415754 411749 407746 400747 393747 390745 
       387742 383736 378731 371728 365728 361729 353732 345738 
       339743 328756 321765 314776 309788 305803 302809 298814 
       295816 294813 291810 288810 285811 280817 274831 272837 
       274841 278843 283840 284838 286840 287844 284851 275860 
       271865 270871 271875 276880 278882 282882 288877 297866 
       302862 305862 307865 311869 314869 317866 318859 321854 
       327848 331841 332827 337815 339809 342803 347801 350802 
       355805 358807 360811 358816 355821 352828 354835 356838 
       360839 369836 376830 381824 383819 387813 392808 397803 
       402799 406797 412793 417786 419765 
  0.01 415064 412061 410058 407061 404062 401064 399068 398073 
       397075 398079 401081 404079 407076 410079 412076 415072 
       415068 415064 
  0.25 508283 511275 512267 513263 512257 511251 510245 509238 
       504226 500217 496213 491210 486207 480207 470210 454214 
       446217 440218 437222 436229 434236 433245 437250 443251 
       452250 461250 468251 473253 480259 488268 495277 498281 
       504284 508283 
  0.25 507174 503169 499163 494158 490156 485156 479156 475156 
       471154 465149 462154 463157 467161 471167 478170 483174 
       487177 492177 498175 507174 507174 
  0.25 483231 482231 480227 477225 478230 479231 482231 483231 
  0.25 453114 454109 453105 453101 450098 447097 444097 441097 
       438100 438101 435104 435108 438109 441110 443113 446115 
       449115 452114 453114 
  0.25 373758 372749 370745 367742 363741 357742 351745 346750 
       339758 330769 325779 324784 323791 323795 326795 329792 
       335784 341779 348777 355774 358770 364765 371761 373758 
  0.50 503271 501266 497261 493256 490247 482239 477232 471230 
       470226 471222 475220 483220 490223 493227 497233 500237 
       502237 504234 501228 498223 493217 488213 481211 476211 
       470214 464215 453217 447220 443223 448228 446232 442236 
       440242 441245 447246 452245 465244 478251 484255 487256 
       489261 495269 498272 502274 503271 
  1.00 464221 463220 460218 457219 457220 458224 459225 462225 
       463224 464221 
  
  
 24HR QP VT 19/00Z
  0.01 531720 528712 526707 521702 517699 509696 504697 498701 
       489710 481714 480708 482703 481697 479691 476683 473680 
       464676 460677 455679 452680 449683 446688 443695 441697 
       433703 430708 428717 426728 425734 423740 418748 414759 
       411770 410778 409789 407796 403806 401819 400823 398828 
       394838 392843 391848 391854 391858 388867 384876 382884 
       382891 383900 385910 385918 384925 382934 380945 379955 
       380958 383962 389967 395966 402963 404960 406956 410955 
       412956 415960 424962 429957 432950 433940 433932 433925 
       429911 426897 423879 421867 422862 421855 422845 424837 
       431815 432809 434807 436811 434817 431827 429836 429859 
       429863 431866 436866 438861 446840 451831 456823 466818 
       475813 480805 485801 492798 497794 501788 503782 505771 
       512767 517764 522761 525757 527752 529749 530744 532736 
       530724 531720 
  0.01 525256 517243 516236 513228 510222 505216 498206 490202 
       482201 478203 475203 471206 466205 462205 459207 452214 
       444213 439214 429219 427225 426231 423234 416236 413241 
       412252 414263 416268 418269 423267 428264 432263 443259 
       448258 454259 462260 467261 470263 476268 485279 490284 
       497287 506291 512289 
  0.01 530199 531195 531191 529184 522176 516168 511164 506161 
       504156 507152 508149 507145 503142 498140 493135 487129 
       482126 476125 469128 467134 468139 471142 476145 480146 
       480151 476150 473148 468141 463140 461140 457142 450145 
       437144 435147 434155 436159 439161 443164 445170 446179 
       441187 439192 439198 444204 445198 445192 448190 451193 
       454192 457189 460186 463183 464178 463173 458169 461165 
       462166 469174 473175 477174 485182 490184 493186 502191 
       508194 521206 525205 528203 530199 
  0.01 477111 476106 472102 471094 470089 465077 465064 470037 
       470033 468029 463026 459030 457034 456036 453035 456022 
       455015 454007 452998 452990 452982 453977 452968 447960 
       441956 437959 434964 432968 432977 439999 440008 439016 
       438024 434031 433038 433044 433048 435051 438056 438064 
       437071 438077 444083 448084 445088 435090 431089 426091 
       425097 424100 421106 423115 426126 428128 431127 436120 
       452126 455122 463124 477111 
  0.01 416064 412058 407056 398053 392050 386049 378047 373048 
       370051 371055 375057 379057 377059 372061 368064 369068 
       373072 374083 376085 378085 381083 389087 387076 389079 
       395080 397082 400081 402079 407072 411075 414071 415066 
       416064 
  0.01 296803 291797 285794 275790 264784 258783 253784 250786 
       249790 247794 243801 240805 242812 247811 251811 254814 
       258817 268822 275825 281825 285824 286821 290819 293818 
       294814 295807 296803 
  0.25 515277 517273 518268 517259 515253 514247 510235 504225 
       502220 498215 491210 485207 479207 471210 461211 455215 
       445218 441219 440222 440227 436239 436242 438246 441247 
       447248 453247 462248 468249 474252 481260 488270 493277 
       498282 505285 509284 513280 515277 
  0.25 488233 489230 488228 486228 483225 480225 477224 475224 
       477226 480228 480230 482233 485236 488234 488233 
  0.25 477164 476161 474159 473157 471154 470153 468150 466149 
       465148 464148 463152 463157 464158 467162 469165 472166 
       475164 477164 
  0.25 454101 453097 450096 447096 447097 444100 441100 439100 
       438101 436104 437108 438109 440108 441108 444112 445113 
       446114 448113 448109 450105 453104 454101 
  0.50 513271 515266 514261 512252 511245 508238 501224 497219 
       493216 486212 482210 478211 474213 471214 472218 480219 
       488223 490227 492234 493240 486238 483238 481236 477230 
       469231 467232 464231 465223 469218 466216 462215 456217 
       447220 445224 449228 449233 447237 444239 445242 451242 
       456241 461241 471246 478251 483257 489266 493273 500279 
       502280 504281 508279 513271 
  1.00 503276 505272 504267 501263 499258 497254 495249 490243 
       488242 484245 484250 485252 487257 490262 492267 497272 
       500275 503276 
  1.00 478243 480239 479237 477234 476233 474233 473237 475242 
       477243 478243 478243 
  1.50 501270 500269 499265 498264 496259 494254 494253 492250 
       490248 489246 488247 488251 488252 490257 493261 494263 
       495265 497268 498269 500271 501270  
  
 

 
 
 

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