Quantitative Precipitation Forecast
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
000
FXUS04 KWBC 150713
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
212 AM EST THU FEB 15 2018


PRELIM DAY 1 QPF DISCUSSION
VALID FEB 15/1200 UTC THRU FEB 16/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1...

...OH-TN VALLEY TO THE CENTRAL AND SOUTHERN APPALACHIANS/ MID
ATLANTIC STATES/LONG ISLAND NY AND NEARBY SOUTHERN NEW ENGLAND ...

THE BROAD MID-UPPER LEVEL WSW FLOW, WITH SUBTROPICAL ORIGINS AHEAD
OF THE UPPER TROUGH SOUTHWEST OF BAJA, WILL ALLOW FOR AN
ELONGATED, ROBUST WARM CONVEYOR BELT/MOISTURE PLUME ("ATMOSPHERIC
RIVER" PER THE ARDT INTEGRATED WATER VAPOR TRANSPORT ANOMALIES)
INTO THE CENTRAL AND EASTERN CONUS DURING THE DAY 1 PERIOD PRIOR
TO THE COLD FRONTAL PASSAGE. THE 00Z GUIDANCE CONTINUES TO DENOTE
A HEAVY RAINFALL SIGNAL ACROSS THE OH VALLEY INTO THE CENTRAL
APPALACHIANS, LAUREL HIGHLANDS, AND INTO CENTRAL PA IN LIGHT OF
THE ABNORMALLY RICH DEEP-LAYER MOISTURE/THETA-E PROFILE ALONG WITH
A VIGOROUS UPPER JET STREAK (170 KTS AT 250 MB), WHICH WILL
PROVIDE ROBUST, SOMEWHAT LENGTHY DEEP-LAYER ASCENT VIA THE
APPROACHING LEFT-EXIT REGION INITIALLY AND (TOWARD 12Z FRI)
ASSOCIATED MORE FROM RIGHT-ENTRANCE REGION FORCING AND
STRENGTHENING LOW-LEVEL FGEN AHEAD OF THE FRONT. PW ANOMALIES
DURING THE EVENT WILL PEAK AROUND 3.5 STANDARD DEVIATIONS ABOVE
NORMAL PER THE SREF AND GEFS, WHICH ALONG WITH THE 850 MB WSW
INFLOW OF 50-55 KTS AND MOISTURE FLUX ANOMALIES OF 4-5 STANDARD
DEVIATIONS ABOVE NORMAL, WILL MAKE FOR NEARLY OPTIMAL RAINFALL
EFFICIENCY/RATES FOR MID FEBRUARY CONSIDERING THE LACK OF
INSTABILITY (MUCAPES <400 J/KG).

IN TERMS OF THE QPF, MUCH OF THE HIGH-RES CAM GUIDANCE WITH RECENT
EVENTS CHARACTERIZED BY STRONG DYNAMICAL FORCING, IMPRESSIVE
MOISTURE PROFILES, AND MINIMAL INSTABILITY (I.E. LARGELY
STRATIFORM) WERE GENERALLY UNDERDONE WITH THE BREADTH OF
MODERATE-HEAVY RAINFALL AREA WHEN COMPARED TO THE GLOBAL GUIDANCE.
THE WPCQPF WAS ESSENTIALLY A BLEND OF THE 00Z ECMWF, GFS, AND
IN-HOUSE BIAS CORRECTED ENSEMBLE MEAN, WHICH MATCHES UP FAVORABLY
WITH THE RGEM AS WELL AS A BLEND OF THE WRF-ARW AND ARW2. THE 00Z
NAM MEANWHILE WAS A NORTHERN OUTLIER WITH RESPECT TO THE MAX AXIS
OF 1.5+ INCH TOTALS.


...SOUTHWESTERN U.S...

THE AFOREMENTIONED ANOMALOUS MOISTURE PLUME WITH A SUBTROPICAL
CONNECTIONS WILL HELP TO INVIGORATE THE WARM CONVEYOR BELT
DIRECTED INTO THE SOUTHEAST AHEAD OF THE SOUTHERN STREAM UPPER
TROUGH. MODEL AGREEMENT IS SUCH THAT A CONSENSUS APPROACH TO QPF
MAKES SENSE THROUGHOUT THE SOUTHWEST REGION. THE MAXIMA ARE
TARGETING HIGHER MOUNTAIN PEAKS IN WINDWARD TERRAIN WHERE
OROGRAPHIC EFFECTS AID LIFT WITHIN THE MOIST PLUME, INCLUDING THE
MTNS AND LOWER MOGOLLON RIM IN SOUTHEAST AZ AS WELL AS THE
SACRAMENTO MTNS IN SOUTH-CENTRAL NM. WPC USED THE 00Z
GFS/ECMWF/NAM CONUS NEST/CANADIAN REGIONAL GEM/HIGH RES ENSEMBLE
MEAN AS A BASIS FOR QPF, WHICH ALLOWED US TO MAINTAIN GOOD
CONTINUITY.

HURLEY


GRAPHICS AVAILABLE ON THE WEB AT
WWW.WPC.NCEP.NOAA.GOV/QPF/QPF2.SHTML



THIS DISCUSSION WILL TRANSITION TO MIXED-CASE FEB 26, 2018.  THE
LISTING OF ISOHYET POINTS CONTAINED BELOW WILL ALSO BE ELIMINATED
FROM THE PRODUCT FEB 26, 2018.  ISOHYET GRID INFORMATION WILL
CONTINUE TO BE GENERATED IN A VARIETY OF BINARY FORMATS AND MADE
AVAILABLE THROUGH THE WPC GIS PAGE.

24HR QP VT 16/12Z
 0.01 499322 488317 483319 479319 475319 470317 460313 456311
      454305 456292 457287 459284 460280 459273 457267 455258
      450249 446245 442244 439245 434243 432242 433239 438235
      441231 440228 437228 433227 437221 438218 440218 449214
      462205 468206 472205 482202 488198 490191 488188 485189
      483189 481184 479180 473179 467182 459185 454192 452193
      448192 444191 442188 445181 449176 450168 449163 447162
      442159 437158 434155 435151 438148 445143 443133 447133
      451130 454125 451122 448122 444121 442117 440114 438116
      436121 433124 428130 421152 418160 413165 415150 420139
      420132 421128 420124 412122 401120 393124 386129 379136
      376143 373146 368145 364144 361142 352139 346138 340131
      336139 331147 329145 330137 326138 322143 316148 313151
      317153 321156 324160 322162 318162 312161 308158 299153
      296150 291149 285148 280148 278145 275144 273146 269147
      265145 263143 260139 261132 263127 266125 268120 270114
      274112 280111 281106 281102 287097 290094 289089 286085
      286082 290079 294077 306076 308073 307069 312062 316056
      319049 320048 326050 329048 333048 345049 352052 363051
      366050 366046 368041 369033 370027 370021 373018 375014
      378010 381008 387008 390004 392007 394013 397018 399021
      399026 402033 401044 401049 404051 417048 420050 421053
      425052 427051 427048 426042 424029 423022 423015 424000
      425995 426988 426982 427978 428974 431964 436956 440947
      447942 452947 456968 457978 459983 462979 464954 465952
      466947 466942 467937 467932 467928 466925 464920 460918
      460911 461906 461898 461891 462886 464881 463853 466850
      468850 470847 469838 470830 470823 469816 466812 461808
      454806 446790 443803 442809 443818 442823 441828 437838
      435851 436856 438858 439856 446850 450847 455847 455853
      454856 450862 443865 439866 437869 437872 434883 431890
      427891 424893 422898 419903 410919
 0.01 410919 406925 403927 400931 397937 393943 391945 386945
      383944 382940 383932 381931 379934 371944 368948 364954
      362960 361967 357983 354990 353991 351987 351966 352960
      351955 347953 346956 343956 340954 336948 334937 333920
      338919 341919 343922 346921 347916 350910 359876 361868
      358862 357852 357849 354848 350850 345851 342845 342840
      344837 348831 355822 362814 368809 374804 378798 380791
      384784 387777 390761 392745 393727 396714 394697 392684
      392674 397660 401655 406651 411649 414650 420653 429660
      437658 439655 443654 446659 446663 448667 450674 451676
      452681 455688 454689 453698 452704 455703 457694 458674
      460666 461663 466662 479657 489656 495645 504649 507659
      509671 514691 516700 518709 519717 519722 518733 518751
      516772 515788 514804 513811 511816 509825 507833 505842
      500861 495877 493886 492894 492904 490909 490916 489924
      489932 486947 482969 482974 481979 480988 477011 476035
      477071 480079 483085 489096 492101 492105 494117 489132
      489135 492138 496145 500150 505156 509160 511162 515163
      516161 519162 520166 523168 527172 529178 531183 533185
      535185 536187 539196 541202
 0.01 505161 504158 502158 502157 501155 499154 497156 498159
      500161 501162 503162 505161
 0.01 428101 427096 424091 423088 425084 427079 425075 422065
      421058 420056 418057 416069 414074 411077 408080 407086
      407094 412096 414105 417106 420103 428101
 0.01 408098 407094 405093 403088 400086 397087 394090 387095
      379101 376100 374098 373093 370095 368102 370106 371107
      373113 376117 380115 385115 389113 393110 396108 400106
      404107 406103 406100 408098
 0.01 385193 386191 385189 384188 382186 380185 379183 379182
      377182 377185 379186 380188 381190 383191 384193 385194
      385193
 0.01 378060 378058 377057 375056 374055 372056 371057 372058
      372059 373060 375062 377062 378060
 0.01 368088 366084 364081 361077 359074 356070 353071 350072
      349075 352078 355082 357086 361087 364087 368088 368088
 0.01 367099 366095 364094 360098 359105 355106 353106 348104
      345105 345107 348110 351110 355113 358113 360112 362110
      365103 367099
 0.01 293893 293889 291889 289891 287893 285893 283896 280897
      278899 278902 280904 284902 286900 288900 290897 291895
      293893
 0.01 247829 246821 246813 242810 238814 236820 237828 238836
      240840 243846 245845 245841 246835 247829
 0.01 235792 235790 234789 234790 232792 232794 231796 230796
      230798 230800 231802 232803 232802 233801 234800 234798
      234796 234794 234792 235792
 0.25 522262 518258 512255 506248 503244 500238 498227 498219
      497216 494214 489212 484212 474212 466214 462218 460220
      460224 463227 467227 474219 480220 483223 487228 489233
      489237 486237 481235 478233 474233 471238 473243 475247
      478251 483255 485266 487272 491278 494281 499284 506287
      513289
 0.25 534212 535209 534208 533206 533205 531204 530203 529202
      528202 527200 525199 524200 524201 522202 522205 523207
      523208 524209 526209 527210 529212 530212 532212 534212
      534212
 0.25 450046 451041 451037 451032 450029 447027 445029 443032
      443036 443038 444043 445046 447048 448048 450046
 0.25 440760 440754 438749 434746 424751 420749 416745 414738
      417732 419724 420718 421711 422702 423689 424681 423677
      421673 418672 415674 413680 411696 407707 404717 402734
      398748 396761 396775 393782 390787 382797 380803 378809
      377821 376831 375839 373854 372869 370880 363911 365916
      370915 375907 379902 385898 388895 392893 395895 400897
      402893 407884 412878 415873 419859 422845 424834 428817
      430801 433787 433773 440760
 0.25 395071 395066 394063 393064 390066 387067 386070 384072
      382074 381076 383078 385077 387075 390073 394073 395071
 0.25 374066 373065 372064 371064 370064 370066 371067 373068
      374066
 0.25 346063 345059 343057 341056 338054 334053 330053 327054
      325055 324059 326061 328062 332062 335064 337065 339065
      342065 346063
 0.25 340096 339090 339084 334078 320072 317076 314079 311083
      308085 301090 297097 295101 294108 294114 292117 281130
      280133 281136 285138 289137 290133 293124 295120 297119
      307121 316121 323117 329111 331107 332102 335099 339098
      340096
 0.50 426791 426785 425782 420777 417773 415767 414758 412752
      409750 406751 401754 400762 400771 398778 396784 387793
      384799 382804 381823 380836 379846 379855 377871 377879
      377884 379886 384889 388887 403868 410855 414842 416835
      418827 421813 426791
 0.50 341061 341060 339058 337057 336056 334055 332055 330055
      329055 327056 325057 327058 328059 329060 330060 332060
      334061 335061 337061 339061 341061 341061
 0.50 323108 324100 325095 324093 319089 315088 311088 308089
      309096 305097 301101 299106 300109 303114 309116 314115
      319112 323108
 1.00 412805 412793 411784 409781 406778 401782 396788 393792
      388798 387806 389826 387843 392856 396856 398853 400846
      406834 408826 410819 412805
 1.00 334058 332057 330057 328057 328058 330058 332058 334058
      334058
 1.50 408801 408791 407787 406785 401787 397791 393795 391801
      392808 395816 398817 399819 402824 404818 406810 408803
      408801
 2.00 405792 405790 405789 405790 403791 403792 404793 405793
      405792

$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.