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QUANTITATIVE PRECIPITATION FORECAST

 
 FXUS04 KWBC 101935
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
234 PM EST TUE FEB 10 2009


PRELIM DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID FEB 11/0000 UTC THRU FEB 14/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR

...DAY 1...

...SYNOPSIS...
SPLIT FLOW REGIME ACRS NOAM WL CONT WITH THREE POTENT SYS MOVG
ACRS THE CONUS THIS PD. ALTHOU MDLS ARE GNRLY ON THE SAME PAGE
WITH THE LRG SCALE FEATRS...THERE ARE SOME TIMG DIFFS. LATEST GUID
HAS SLOWED THE EWD PROGRESS OF THE CNTRL U.S. VORTEX...WHILE OLDER
GUID REMAINS SLGTLY SLOWER. NAM/GFS SEEM TO BE HAVG SOME
DIFFICULTY WITH DVLPG CNVCTN IN THE WRM SECTOR...AS HAS BEEN THE
CASE FOR THE PAST COUPLE OF YEARS. NRN PLNS LOW WL QUICKLY EXIT
STAGE RGT...WHILE ANOTHER POTENT MIDLVL SYS DROPS INTO THE WRN
U.S..

...NCNTRL U.S...
POTENT/VERTICALLY STACKED LOW OVR THE UPR MS VLY WL QUICKLY
WEAKEN/EXIT THE REGION TNGT WITH MAINLY LGT SNWS ACRS THE REGION.
STG WINDS WL CONT TO CAUSE CONSIDERABLE BLOWG/DRIFTG.

...SRN PLNS/LWR MS VLY NEWD INTO THE LOWER GRT LKS...
MDLS ARE SHOWG THE BIGGEST TIMG DIFFS THRU THIS REGION WITH THE
OLDER ECWMF SLOWER THAN THE LATEST GUID. INTERESTG TO SEE IF THE
12Z ECMWF IS SLOWER. THERE MGT BE SOME JUSTIFICATION FOR SLOWER AS
THE MIDLVL SYS TRANSITIONS FM AN OPEN SHRTWV TO A CLSD SYS. AS
THIS OCCURS AND THE NCNTRL U.S. VORTEX LIFTS INTO CAN...MDLS ARE
SHOWG THE DVLPMENT OF A VRY IMPRVS UPR JET COUPLET/DVRG MAX THAT
WL PROVIDE A BROAD REGION OF DEEP LYRD LIFT ACRS THE REGION.
LOLVLS ARE ALRDY READY RESPONSG WITH INCRSG DEEP LYRD SRLY FLOW
THAT WL STRENGTHEN TO 50-70 KTS IN THE 8H-7H LYR AND SUPPORT A
PLUME OF UNSEASONBLY DEEP MSTR WRKG INTO THE MIDWEST/GRT LKS THAT
WL FUEL A LRG REGION OF MOD/HVY RNFL. THE STG LOLVL FLOW WL
OVERRIDE A BNDRY DRAPED ACRS THE REGION WITH MDLS SHOWG VRY
FOCUSED/STG 8H-7H CVRG WITH A BROAD REGION OF ISENTROPIC LIFT. PWS
OVR THE SRN PLNS/MID MS VLY SHLD APRCH 1.50 INCHES WITH VALUES IN
THE 1.00-1.25 INCH RNG WRKG INTO THE LWR GRT LKS. LATEST SREF
OUTPUT INDICATES PWS ANOMALIES OF 2-3 STDS OVR THE SRN
PLNS/MIDWEST TO ABT 4 STDS OVR THE LWR GRT LKS. THIS DEEP MSTR
COMBINED WITH THE AOA 50 KTS 8H-7H FLOW IS SUPPORTG MSTR FLUX
ANOMALIES OF 4-6 STDS ABV NRML. A VRY STG SIGNAL FOR HVY RNFL.
XPCT CNVCTN TO REMAIN SOMEWHAT DIS-ORGANIZED FOR THRU THIS
AFTN...BUT INCRS/ORGANIZED DRAMATICALLY TNGT AS THE SFC
BNDRY/DRYLN PUSHES INTO THE MOIST AXIS AND HGT FALLS MOVE EAST.
XPCT A LRG AREA OF MOD/HVY RNFL WITH THE ZONE OF HVIER RNFL ACRS
ARK/MO INTO THE MIDWEST WHERE LCL 3-4 INCH TOTALS ARE PSBL.

...WRN U.S....
POTENT GULF OF AK VORTEX SLIDG SEWD TWD THE PAC NW WL CONT SWD
INTO WED. ALTHOU THE SYS IS DYNAMICALLY STG WITH VRY LRG HGT
FALLS...UPSTREAM DIFL AND UPR DVRG AT THE NOSE OF THE STG UPR
JET...THE SYS IS SOMEWHAT DEVOID OF DEEP PAC MSTR. THIS SHLD LIMIT
THE HVIER PCPN AMTS TO THE CSTL RNGS/SIERRA WHERE UPSLOPE WL
COMBINED WITH THE STG DYANMICS. THREAT FOR HVIEST PCPN SHLD BE OVR
NWRN CA/SWRN OR CSTL RNGS INTO SHASTA/SISKIYOUS.

DAY 2...

...GREAT LAKES/NORTHEAST....

MDT PRECIP IS EXPECTED EARLY IN THE PERIOD AS THE COUPLED UPR JET
CROSSES THE GREAT LAKES AND THEN CONTINUES DOWNSTREAM ACRS NEW
ENGLAND LATER IN THE PERIOD.
COMBINED WITH 50+ KTS OF SLY LOW LVL INFLOW SUPPORT A WELL DEFINED
850-700 MB THETA-E ADVECTION MAXIMA CROSSING NORTHERN NY-NORTHERN
NEW ENGLAND AND THEN HEADING INTO THE CANADIAN MARITIMES. THE NAM
IS SLOWER MOVING THE 700 MB NORTH ACROSS THE REGION AND HAS A
STRONGER UPPER DIVERGENCE MAXIMA...THUS RESULTING IN HIGHER QPF
AMOUNTS. MANUAL PROGS USED THE CONSENSUS CLUSTER OF THE
GFS/UKMET/ECMWF/CANADIAN MODELS WITH HIGHER AMOUNTS FURTHER NORTH.
STRONG BNDRY LYR WINDS CROSSING LKS ERIE/ONTARIO WILL RESULT IN
DEVELOPING POST-FRONTAL LK ENHANCED SHOWERS/SNOW BANDS. THE QPF
AXIS LINES UP WITH THE LONGER CROSS LK ERIE TRAJECTORIES (SEE THE
WINTER WEATHER GRAPHICS FOR AMOUNTS/DETAILS).

...CALIFORNIA/GREAT BASIN...

THE NEXT IN A SERIES OF SHRTWVS IS FCST TO SLIDE SEWD ACRS OR/NRN
CA AND THEN EAST INTO THE GREAT BASIN THIS PERIOD. SOME AMTS OF A
QUARTER TO HALF INCH ARE EXPECTED ACROSS THE CA SIERRA...WITH
LIGHTER MAXIMA IN NV/UT/WESTERN CO AS THE CLOSED LOW SHEARS INTO
AN OPEN WAVE AS IT CROSSES THE GREAT BASIN. LIMITED MOISTURE AND
FCST WEAK VERTICAL MOTIONS SHOULD PRECLUDE HEAVY AMTS. MODELS
HANDLE THIS SYSTEM SIMILARLY THRU THE END OF DAY 2 PERIOD. THE
HPC FORECAST REFLECTS A BLEND OF THE NAM/GFS/ECMWF.


DAY 3...

...CENTRAL PLAINS/MID MS VALLEY...

THE MODELS HAVE TIMING AND INTENSITY DIFFERENCES REGARDING THE
SHRTWV EMERGING OUT OF THE CENTRAL ROCKIES AND THE DEVELOPMENT OF
AN 850-700 MB LOW. THE MODELS WITH DEEPER LOWS HAVE HIGHER
QPF..WITH GFS THE MOST DUE TO ITS STRONGEST 850-700 MB LOW. THE
QPF CONSISTED OF CONSENSUS ECMWF/NAM/CANADIAN GLOBAL AMOUNTS. THE
AXIS AND ORIENTATION FOLLOWED THE 12Z NAM AXIS OF STRONGEST
850-700 FRONTOGENESIS AND DEFORMATION/THETA-E ADVECTION
MAXIMA...WHERE THE NAM QPF IS LIGHT (NAM QPF SEEMS TO BETTER
FOLLOW THE 300 MB DIVERGENCE FURTHER NORTH).
SEE THE WINTER WEATHER DESK FORECAST FOR SNOW AMOUNTS.

...CALIFORNIA...

YET ANOTHER MID/UPR LVL LOW IS EXPECTED TO DROP SEWD FROM THE
NORTHEAST PACIFIC TOWARDS CA THIS PERIOD...BRINGING LGT/MDT AMTS
TO THE REGION. THE MODELS HAVE TYPICAL TIMING/PHASING DIFFERENCES
WITH THE SHRTWV AND ASSOCIATED SFC LOW. THE 12Z NAM CONTINUES TO
FCST THE SFC LOW A BIT FURTHER TO THE W THAN THE 12Z
GFS/ECMWF/UKMET/GEFS MEAN. A BLEND OF THE AFOREMENTIONED CLUSTER
WITH CONTINUITY WAS USED FOR MANUAL QPF.

GULF COAST...
THE MODELS HAVE A SIGNIFICANT SPREAD IN QPF AMOUNTS ALONG THE GULF
COAST DUE TO PHASING DIFFERENCES AND TIMING DIFFERENCES IN THE
EASTWARD PROPAGATION OF THE UPPER LEVEL JET AND ASSOCIATED
DIVERGENCE MAXIMA ALOFT. THE 06-12Z GFS/00Z UKMET IS HIGHER AND
FURTHER EAST IN ITS QPF VS THE NAM/ECMWF...WITH EACH TIMING
ACCORDING TO MOISTURE RETURN OF HIGHER PW VALUES AND LOW LEVEL
CONVERGENCE ALONG THE GULF COAST. MANUAL PROGS USED AN IN
BETWEEN/CONSENSUS SOLUTION CLOSE TO THE 12Z UKMET/CANADIAN GLOBAL
FOR NOW WITH LOWER THAN NORMAL CONFIDENCE.

ECKERT/PETERSEN

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV

24HR QP VT 12/00Z
0.01 370803 343824 312849 296869 287885 283906 284923 285960
286995 296998 316983 340978 358980 358993 359008 370014
374023 362023 351013 343016 338027 348053 359061 361067
370072 373066 370061 385066 391085 406080 417076 414060
400048 395023 401984 417924 439899 459849 465800 463754
466725 480701 481669 455653 445674 451691 447712 438733
429758 418780 410772 403741 397740 391754 389769 384792
370803
0.01 533999 533991 532985 529975 525966 524957 523948 521938
518926 516911 514901 508895 504892 502886 500879 497867
492859 488855 485852 481850 479855 477862 476869 477875
475884 468898 466906 471911 470918 467927 466944 465967
464973 464980 465988 465997 467009 472016 476020 482025
486027 490028 496029 505028 511025 517019 520011 523007
527006 533999
0.01 486265 494278 507282 512261 502225 492206 480205 468209
461206 455204 457195 468184 462175 458167 467169 476169
477160 475145 485138 476128 467131 460127 459117 469112
466103 455097 439092 431090 424093 420104 412108 408112
408125 413135 403144 397151 391170 397170 405170 409185
412197 403200 389188 365177 351179 343176 340181 338195
346209 359229 373248 398265 429271 461262 470253 474251
477251 484259 486265
0.01 441210 441209 440206 439202 439201 437197 437196 435193
435189 435187 432188 429191 428191 425193 424194 423198
425199 427203 429206 431208 432209 435211 438211 441211
441210
0.01 441125 440120 436120 433124 430128 428133 426139 426147
426155 429159 432160 432157 430151 430144 431140 433137
435132 438128 441125
0.01 371205 370201 369200 367197 366197 364195 361193 361192
359191 356190 353190 352190 350193 351197 352198 355200
357201 360202 363203 365205 368207 371205
0.25 453784 449776 447774 443773 440775 436780 433786 429792
423797 417802 409806 405808 400808 395805 390804 386807
374818 371820 367821 363817 353825 349830 346837 333860
331865 330872 330882 327887 321897 315909 309922 307935
303946 302953 301958 302962 306969 310974 313975 316974
321971 346962 352961 356961 360963 369971 372977 373982
373987 373991 375995 379995 384994 389989 393982 396975
398969 401954 403935 405927 407921 411914 414909 422897
430884 437872 443858 448843 452827 454815 455803 454792
453784
0.25 452222 447219 440218 430221 420225 417225 417221 416216
405209 395201 389198 384194 374188 370187 366188 369194
376202 385212 388216 385219 380222 376226 376231 378236
382242 387246 391249 399251 413256 424258 431257 436254
444245 445240 443238 439237 436235 435231 440227 448225
452222
0.25 445109 444107 441104 440108 441109 444110 445109
0.25 453189 453185 450188 452192 453189
0.25 362217 361213 359210 357209 356208 355208 354212 355214
357216 358217 360218 362217
0.25 418157 418155 417157 417158 418157
0.50 447805 447798 444793 440794 438797 432803 427807 416812
409817 404821 401823 398821 394816 390813 387816 382821
374834 370840 365843 362842 360839 357835 355834 353835
351839 350846 350850 351854 356857 364853 370850 374848
377849 379851 380856 378862 372867 358874 352877 346881
340887 337893 336900 332906 325915 318927 315935 312942
311949 311953 314961 318966 327964 332961 338956 343951
350947 354946 360949 364955 369959 373964 375968 380976
384978 390975 393969 395961 397944 398935 400927 403918
406912 413901 418894 422887 426881 430875 434867 437860
439852 441846 444828 446815 447805
0.50 433245 431241 429238 423233 415227 413216 408215 405213
400208 392202 384198 377193 374195 377199 382205 388209
395215 401223 396225 389224 386224 383226 382229 384237
390242 397246 414251 424252 428252 432249 433245
1.00 412886 424866 433848 433827 426824 419828 413837 402859
390874 376881 370887 362895 353900 337913 323937 321951
323958 326958 338949 344937 349931 354928 358932 363941
368948 375951 381953 388950 391940 399912 412886
1.00 425243 422238 419236 414232 412228 410226 410222 409222
408229 405233 403236 404237 409241 412242 415243 421244
425243
2.00 392912 396902 406883 408872 400876 387890 382896 378902
375907 372911 368917 368923 370928 375931 382931 386927
390922 392912
3.00 385909 379917 379910 384907 385909

24HR QP VT 13/00Z
0.01 484585 478581 472582 467582 460587 456590 452595 442610
439614 435616 425620 404639 391651 381659 367670 355678
348683 340693 336697 331701 327708 321721 316731 310742
307753 302773 297792 295806 294810 293816 288826 283836
275853 269862 266869 266874 267879 268883 270884 275886
279884 303874 314869 321867 325863 340851 344848 348846
355843 364839 376838 382838 386845 391856 394861 397866
404874 407877 412879 418883 424884 428886 435883 442881
448877 450877 452879 455884 456893 456900 458918 466944
468950 471956 474960 482970 491981 500990 506993 510994
515993 517986 520973 521958 516913 515907 512897 507876
506870 504864 502860 498840 494821 492812 491803 492793
493785 494770 495753 496734 496726 497721 499707 502692
504679 505663 505646 504632 502624 502622
0.01 531185 532180 532176 531170 528164 526162 522159 520155
515150 504136 499131 495128 491127 485125 480121 478118
476116 478113 479107 477098 474091 469087 466089 464093
462097 459097 454093 450093 442095 435097 431099 429102
427105 422106 414103 413100 414095 415087 415079 418072
418064 415059 409055 407053 404052 401053 398057 393064
389068 386075 374076 376085 375096 375101 379102 385099
389101 389106 388108 385112 382110 379109 374112 371115
367118 363119 356117 353116 348116 347118 348123 351129
355134 359140 360145 358151 358155 360159 363163 367169
368172 367176 360176 355177 345182 342187 341190 340198
341209 343215 351226 357233 362237 367241 375245 387250
397251 401253 401256 402263 407267 412269 421272 435274
469280 474276 476271 477265 476255 474251 472248 464243
449238 438235 431236 422236 418234 417232 419229 430218
432211 430204 426198 419194 412193 408192 405189 403185
398189 395186 399181 403171 402163 406158 408154 409149
410142 409136 405131 396128 397126 401127 407125 411125
419124 421127 422133 425135 427130 430124 434119 440116
448121 449122 452118 455112 461116 468120 468126 469132
456143 453147 444146 441147 439151 441156 443158 446165
447170 447175 443181 439185 440191 442193 445192 447191
450190 452192 455193 460186 462183 462180 458171 455162
458159 461161 486178 490179 496179 499179 501182 506185
508189 513193 520189 526188 531185
0.01 494212 496208 494207 492204 491202 490199 487198 484200
482200 480202 479204 480205 482209 483209 485211 488212
491213 494213 494212
0.01 377748 373748 370750 362753 357756 354759 350763 346770
343778 341782 339787 344783 348781 352778 356774 361768
367761 372756 376751 377748
0.01 404098 404095 404092 401094 400098 400102 401102 403099
404098
0.01 371205 369201 366200 363199 361196 361195 358194 355194
354194 355198 358200 360200 363203 366204 368205 371205
371205
0.25 491638 488626 484617 481612 478611 471611 468612 462616
456622 451629 438642 434647 431654 431661 434668 436675
436682 434698 433706 430713 424735 421743 417749 408759
403765 401770 398780 395787 388792 383796 382804 384807
386809 391810 401809 407810 412813 417818 422821 426823
430827 432833 432838 429847 429853 432863 436867 440868
447866 458861 464848 469834 473821 476808 478790 479773
481743 484727 487710 490697 491691 491682 491670 492657
492646 491638
0.25 502940 501935 501934 498931 497930 495932 495937 497941
499943 501941 502940
0.25 403216 404212 403210 400206 398203 392201 387197 384196
379193 374191 371190 372196 375199 378203 383207 385209
389213 393216 398218 403216
0.25 409110 409106 409104 406102 405106 403110 400111 397111
394113 397114 400114 403116 406116 408114 409112 409110
0.25 394154 397147 392143 390141 384141 381141 378139 375140
377144 378148 377154 377156 377159 379162 382165 388165
391163 392157 394154
0.25 386120 385117 383116 380117 379119 379121 381123 382124
384123 385122 386120
0.50 478681 476672 474665 470657 466652 462652 458656 453660
451665 451676 448687 446697 444707 440716 436723 436728
435737 431745 422766 419774 414781 409786 407789 406794
407797 419809 423810 429809 438807 441808 444813 446819
446827 444837 440847 438852 439858 442859 447859 452855
454851 458840 461831 465822 468811 470799 472777 473765
473752 474741 475732 479705 479696 478685 478681
1.00 461756 459744 456740 452740 448747 446757 445767 445775
446783 449791 453797 456791 458781 460775 461765 461756

24HR QP VT 14/00Z
0.01 490645 486636 482626 476621 470617 461614 455613 451613
446615 444618 443622 442625 440630 434631 428634 423636
417642 414646 412653 413661 418670 423673 434675 439679
442678 447680 448685 448688 445704 443711 438717 435723
435728 439730 441734 439739 435741 427745 423750 423758
422766 420772 416776 413781 405785 390795 386798 385802
387805 392805 399803 404802 410804 412805 415810 417811
419816 427826 435832 440834 445831 447827 446821 442814
439806 437796 438784 440776 443768 448764 452756 454749
455741 456728 457720 460711 475699 479696 483689 486681
488674 490656 490645
0.01 523948 522941 519937 515931 508924 501916 497909 492901
489898 484896 477894 466880 457879 455884 456891 457903
460912 462915 465922 469930 475938 481945 487951 494954
502957 509957 518954 523948
0.01 516176 515171 510166 502159 505158 508153 509147 505142
500137 491127 485116 483111 485103 486098 486090 485085
481081 478081 476083 471080 462072 456068 453066 449064
441064 438063 437059 439056 444056 447051 449046 449041
448036 445031 431010 429004 429994 430986 431981 431975
430962 430944 427913 426905 424896 420880 414864 410859
405855 401853 396855 393859 390863 388870 386875 384887
382892 381897 379912 378921 379928 378936 379946 379959
378969 377973 375986 376000 377015 377031 378037 381043
384049 386053 387057 384058 378058 374057 369058 364060
362066 364072 367075 369079 369083 367089 370097 374101
378101 383097 387094 389094 390098 396102 395107 392109
374117 364118 354117 351120 353124 359127 363130 365132
366137 367139 370140 377143 382133 385127 388123 394117
397120 400120 403119 407120 411121 414118 417114 427107
432102 433095 429089 426086 432077 435075 438078 441081
447084 450088 449089 447086 446088 444094 446100 448107
449112 449117 449120 451123 454125 459126 462128 468132
473139 483144 489148 489152 488157 487160 489165 492169
501174 506175 511178 516176
0.01 471281 460253 462249 467246 469242 470232 472226 473220
472216 470212 466210 458207 453205 448201 445195 448191
451186 451180 449177 445176 442178 436181 433184 430185
426183 427179 430174 431167 429165 425166 422167 419166
419162 420157 421153 420149 417147 410145 404144 401145
398149 395154 390153 387153 385154 383162 382171 378170
373167 366165 358163 341161 331163 327167 324172 321178
318185 317189 317194 320201 323213 327223 333233 337237
343241 349243 355245 357253 359258 362262 366264 370264
373262 377264 381268 386272 391275 396275 402274 413272
419270 425267 430267 436269 443273 447277 453282 458286
463289 469285 471281
0.01 462114 461114 458114 461115 462114
0.01 424084 421082 418080 417084 418087 419088 421087 424084
0.01 403190 404186 404182 404179 404178 403174 401171 398172
398173 395177 392179 389179 392182 393184 394184 397188
399189 402190 403190
0.01 329827 326816 321805 313792 308785 305782 300782 295787
291795 286809 283823 281840 279855 277874 277888 277909
278926 279937 282946 284950 288952 294953 304952 309951
314948 319944 323937 324917 323908 324898 326879 327872
328862 329843 330836 329827
0.25 433245 430240 423234 419230 417224 416216 412208 408204
403201 387194 377188 366181 360178 352180 348179 344174
339175 335180 333186 334193 336199 340204 354222 358230
363234 369245 375247 379249 384249 388250 394252 400256
406256 419256 425254 429252 433245
0.25 422966 422958 422949 420935 418927 416921 410914 406911
402911 399914 396918 394930 393941 393954 393968 394980
393994 392006 391016 391022 393028 398037 401039 404037
406033 407026 411014 415006 419995 420985 422966
0.25 317849 316842 314836 311832 308830 305829 298830 295833
294837 291846 289855 288864 288874 288895 289905 291913
296923 298925 304925 306922 309918 312910 314900 315890
316870 317849
0.50 409233 410230 409226 404228 400231 396232 391230 385228
379226 376228 376230 376232 378234 381235 386237 392239
398239 401239 407237 409233
0.50 417971 417959 415948 412941 410937 406936 403943 401951
400959 400970 400981 402993 404998 405000 410999 413991
415983 417974 417971
0.50 403213 403209 400205 395202 386199 382198 378199 376201
375206 369208 364210 366217 371219 375218 380214 383213
387213 396216 402216 403213
0.50 348207 348206 345205 345206 348207 348207
0.50 310868 309859 307854 305851 301857 299862 296869 295877
294883 296893 299899 304899 306896 308889 309882 310875
310868






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