Quantitative Precipitation Forecast
Issued by NWS

Home | 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 50
000
FXUS04 KWBC 250954
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
454 AM EST THU DEC 25 2014


FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID DEC 25/1200 UTC THRU DEC 28/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


1000 UTC UPDATE

NO SIGNIFICANT CHANGES MADE TO THE PRELIM DAY 1 QPF FOR THE FINAL
ISSUANCE

DAY 1

GREAT BASIN---SOUTHWEST---CENTRAL ROCKIES INTO THE LEE OF THE
NORTHERN TO CENTRAL ROCKIES

STRONG HEIGHT FALLS MOVING SOUTHEASTWARD FROM THE PACIFIC
NORTHWEST INTO THE GREAT BASIN EARLY THIS MORNING WILL CONTINUE TO
AMPLIFY INTO A CLOSED LOW DAY 1 OVER THE GREAT BASIN.  WIDESPREAD
MODERATE PRECIPITATION TOTALS LIKELY AHEAD OF THESE AMPLIFYING
HEIGHT FALLS THROUGH EASTERN PORTIONS OF THE GREAT BASIN--ACROSS
THE SOUTHWEST---INTO THE CENTRAL ROCKIES AND EASTWARD INTO THE
CENTRAL TO NORTHERN HIGH PLAINS.  LATEST MODEL GUIDANCE IS IN GOOD
AGREEMENT WITH THE LARGE SCALE EVOLUTION OF THIS TROF AND THE
ASSOCIATED PRECIPITATION DISTRIBUTIONS ACROSS THESE AREAS.
HEAVIEST PRECIPITATION TOTALS LIKELY THROUGH THE WASATCH INTO THE
TETONS--ACROSS THE  CO ROCKIES AND EASTWARD INTO THE CENTRAL TO
NORTHERN HIGH PLAINS WHERE THE LARGE SCALE LIFT AHEAD OF THE
AMPLIFYING UPPER TROF WILL BE ACCENTUATED BY POST FRONTAL UPSLOPE
FLOW IN THE WAKE OF THE ARCTIC SINKING SOUTHWARD DAY 1 IN THE LEE
OF THE CENTRAL ROCKIES.   SEE THE LATEST QPFHSD FOR FURTHER WINTER
WEATHER DETAILS.

EAST COAST

THE FULL LATITUDE UPPER TROF MOVING OUT OF THE MS VALLEY AND INTO
THE EASTERN U.S. EARLY DAY 1 WILL PUSH THE ASSOCIATED FRONTAL
BOUNDARY OFF THE ENTIRE EASTERN U.S. SEABOARD EARLY DAY 1.
PRECIPITATION ALONG THE FRONTAL BOUNDARY MAY LINGER EARLY DAY 1
OVER EASTERN MAINE---WITH MODEL CONSENSUS OF MODERATE TOTALS IN
THE .25-.50" RANGE CHRISTMAS MORNING.

SOUTH FLORIDA INTO THE KEYS

FRONTAL PRECIPITATION ALSO POSSIBLE ACROSS FAR SOUTH FLORIDA DAY 1
WHERE PW VALUES WILL REMAIN WELL ABOVE NORMAL.  MODEL CONSENSUS IS
FOR LIGHT TO MODERATE TOTALS FOR SOUTH FLORIDA---WITH THE HI RES
NSSL WRF---ARW---NMMB AND NAM CONEST SHOWING POTENTIAL FOR HEAVY
TOTALS ALONG THE IMMEDIATE SOUTHEAST COAST AND INTO THE KEYS.



DAY 2...

...SOUTHERN AND CENTRAL ROCKIES/SOUTHERN AND CENTRAL
PLAINS/MISSISSIPPI VALLEY/MIDWEST...

A RELATIVELY LONGWAVE TROUGH WILL SHEAR INTO TWO LESS PRONOUNCED
SYSTEMS...ONE PORTION LIFTING NORTHEASTWARD TOWARD THE UPPER
MISSISSIPPI VALLEY AND THE OTHER REMAINING PORTION REINFORCED BY A
SHORTWAVE MOVING SOUTHWARD DOWN THE WESTERN SIDE OF THE MEAN
TROUGH.  IN GENERAL...THESE SYSTEMS ARE CHARACTERIZED BY A
SHEARING POSITIVELY TILTED APPEARANCE AND THE CORRESPONDING QPF
FORECAST IS WIDESPREAD BUT NOT PARTICULARLY IMPRESSIVE.  FROM
COLORADO ACROSS THE CENTRAL PLAINS TO THE MIDWEST...PRECIPITATION
VALUES WILL REMAIN GENERALLY BELOW .25 INCH. HIGHER AMOUNTS ARE
LIKELY OVER THE HIGH PEAKS OF CENTRAL AND SOUTHERN COLORADO.
INCREASING MOISTURE WITHIN SOUTHERLY FLOW FROM THE GULF OF MEXICO
LIFTED NEAR THE SLOW MOVING COLD FRONT CROSSING THE SOUTHERN
PLAINS STATES WILL PRODUCE AN AREA OF SHOWERS/RAIN WITH AMOUNTS
GENERALLY BETWEEN .25 AND .5 INCHES FROM NORTHEAST TEXAS ACROSS
EASTERN OKLAHOMA AND WESTERN ARKANSAS. SOME CONVECTIVE ENHANCEMENT
NEAR THE GULF COAST COULD ALSO RESULT IN AMOUNTS GREATER THAN .25
ALONG THE CENTRAL GULF COAST. FOLLOWED THE 12Z ECMWF/NAM IN
HELPING REFINE CONDITIONS RESPONSIBLE FOR QPF.


DAY 3...

...OHIO VALLEY/TENNESSEE VALLEY/MIDDLE AND LOWER MISSISSIPPI
VALLEY/GULF COAST...

THIS QPF EVENT IS A CONTINUATION OF THE ONE DESCRIBED FOR DAY 2.
THE NORTHERN PORTION OF THE TROUGH...A PROGRESSIVE BUT RELATIVELY
WEAK SHORT WAVE MOVING FAIRLY RAPIDLY EAST NORTHEASTWARD  FROM THE
MIDWEST TO NORTHERN NEW ENGLAND WILL BE ASSOCIATED WITH SURFACE
WAVE OF LOW PRESSURE AND A SLOWLY SUBSIDING COLD FRONT FROM NEW
ENGLAND TO THE OHIO VALLEY BY SUNDAY MORNING.  MOSTLY LIGHT SNOW
WILL FALL TO THE NORTH OF THE LOW PRESSURE SYSTEM FROM THE UPPER
MIDWEST ACROSS MOSTLY SOUTHEASTERN CANADA AND NORTHERN MAINE. HAVE
FOLLOWED THE 12Z ECMWF AND HAVE TAKEN INTO ACCOUNT THE SLOWER
SPEED AND GREATER MOISTURE OVER THE GREAT LAKES OF THE 00Z RUN.

MEANWHILE...INCREASING MOISTURE OFF THE GULF OF MEXICO WILL
CONTINUE TO BE IMPORTED FROM THE GULF NORTHWARD AS THE TROUGH OVER
THE SOUTHWEST US MOVES EASTWARD ON SATURDAY NIGHT INTO SUNDAY
REACHING TEXAS/OKLAHOMA BY EARLY SUNDAY.  LOW PRESSURE APPEARS
LIKELY TO DEVELOP OVER THE LOWER MISSISSIPPI VALLEY/LOUISIANA BY
SATURDAY NIGHT WITH ANOTHER BOUT OF INCREASING RAIN/CONVECTION
DEVELOPING ALONG THE CENTRAL GULF COAST ON SATURDAY/SATURDAY
EVENING.  AGAIN FOLLOWED MORE OF THE ECMWF/ECMWF MEAN FORECAST
WITH SOME RELATIVELY CONSISTENT FORECASTS BETWEEN THE 12Z AND 00Z
RUNS.  QPF AMOUNTS INCREASE DRAMATICALLY ACROSS THE CENTRAL GULF
COAST WHERE 2 TO 3 INCHES ARE EXPECTED.  AS A RESULT AND FLASH
FLOOD GUIDANCE VALUES NEAR 3 INCHES...HAVE ELECTED TO INCLUDE A
SLIGHT RISK OF EXCESSIVE RAINFALL OVER THAT REGION.

...PACIFIC NORTHWEST/NORTHERN ROCKIES...

A POTENT SHORTWAVE TROUGH WILL DIVE SOUTHEASTWARD OVER THE PACIFIC
NORTHWEST ON SATURDAY INTO EARLY SUNDAY WHILE A RIDGE OVER THE
EASTERN PACIFIC AMPLIFIES SIGNIFICANTLY. MUCH OF THE PACIFIC
NORTHWEST AND PORTIONS OF THE NORTHWESTERN ROCKIES WILL SEE
MODERATE AMOUNTS OF QPF WITH HEAVIEST AMOUNTS IN THE CASCADES AND
ACROSS THE BITTERROOTS.  AMOUNTS WILL GENERALLY BE IN THE .5 TO 1
INCH RANGE WITH GREATER AMOUNTS IN THE HIGHEST ELEVATIONS. SEE THE
HEAVY SNOW DISCUSSION FOR ADDITIONAL DETAILS...WITH THE FORECAST
EMPHASIZING RECENT ECMWF/GFS RUNS BUT DISCOUNTING THE
CANADIAN/UKMET WHICH APPEAR TO BE MORE OUTLIER SOLUTIONS.

MERRY CHRISTMAS

ORAVEC/KOCIN

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

24HR QP VT 26/12Z
 0.01 492612 499623 505637 508644 511649 515661 525685 527691
      529697 532709 536727 538736 540744 541753 543758 542774
      542785 543792 544799 540802 527816 526818 524817 519819
      513820 507818 498815 491810 483805 478802 476801 472801
      455799 467719 464718 460718 453721 446723 441726 429729
      418731 412731 406732 397738 393741 388742 379744 367741
      360740 357740 355741 348743 344746 334750 316763 302774
      284789 276794 269801 241823 230828 225829 225823 227814
      234806 236800 238797 245790 254785 258783 261780 265776
      269771 277763 290749 298741 301736 304733 315720 324711
      331702 339695 349690 359683 368678 384667 386662 387657
      389646
 0.01 505148 504143 502139 499137 496136 489133 483129 480127
      476126 472131 470134 470140 477138 481139 485141 492144
      494146 498148 502149 505148
 0.01 493222 494217 493213 489209 483209 477210 456213 436218
      428218 424219 422222 426225 427231 425236 420235 415237
      409237 407240 407244 409247 411249 416251 421251 427251
      432250 444250 465248 472247 477247 479241 479236 478234
      471234 469229 471223 476222 486221 491223 493222
 0.01 483161 483158 479157 475155 472153 467146 467135 472119
      474112 475102 473091 469087 468084 467079 468057 468048
      467044 467038 466030 463020 461010 461001 461989 462981
      462976 464972 464965 463931 462924 461919 459917 455922
      453930 450938 448942 443942 438945 433949 425960 420972
      410000 405011 401014 397018 393023 390026 388027 376035
      374043 374046 376048 384056 385059 383062 384065 383069
      380064 375060 373060 373056 374050 371049 369050 365051
      363052 356054 348055 332052 328052 326053 322056 318061
      314066 309078 305081 299082 291089 289096 289098 290102
      291104 295105 304107 308114 308121 313126 317125 323114
      327110 333112 338111 342116 347118 350122 352129 353133
      356135 361139 367136 369134 374136 381139 387142 388145
      388149 388153 389157 388161 386163 385171 383177 382184
      384190 387191 386187 386182 390182 393184 397182 404179
      407173 408164 411157 411152 408150 402152 399148 401142
      404139 410139 413133 415135 414140 415146 415155 415160
      418162 422163 423167 418170 416173 418175 421176 425174
      428173 429171 429168 427161 426153 427148 429144 432131
      435126 438126 439128 436136 435143 436146 436151 436155
      437158 443163 446172 446175 444179 442181 440185 438194
      439200 442205 445206 447205 459185 460181 459178 457175
      457170 459165 461164 469165 478165 482163 483161
 0.01 453852 453850 453847 453845 451843 451840 449840 447841
      446843 445843 446846 446848 447850 448851 449853 450853
      451853 453852 453852
 0.01 444742 440739 435740 431742 430747 431752 433759 434763
      438766 439760 440755 441750 443745 444742
 0.01 430788 429779 425777 422780 418783 415783 413786 410786
      403788 404792 406794 409798 415802 419804 422806 427800
      428795 428790 430788
 0.01 401793 396791 395793 389794 386797 383800 381802 378807
      378810 384809 387806 389804 391801 394801 397798 398794
      401793
 0.01 389109 388106 386105 381104 378105 375105 373100 371102
      369104 366107 360105 358103 352099 349090 348081 351079
      354080 357080 359076 357071 355067 351066 346068 344072
      343078 342081 339084 339089 340093 343098 347107 353112
      357115 361116 367117 373117 377117 383113 389109
 0.01 364186 365184 364184 363183 361183 359182 357182 356182
      354181 353182 352183 351184 350185 349185 349186 351186
      353187 355187 356187 358188 360188 362188 364187 364186
 0.01 339168 336166 331164 327162 324160 320160 317164 319167
      322169 328172 331174 335174 338170 339168
 0.25 469620 476624 480628 485632 488639 488651 485658 478666
      480672 480679 479683 475683 461683 454685 448688 437696
      423704 410709 393714 386717 381717 374714 366715 358716
      353713 353707 354702 358698 363693 369689 383681 392674
      414655 424645 427640 429634
 0.25 538759 535754 533748 529734 525721 521707 517695 511686
      507683 501685 496694 495697 494702 495708 497722 496730
      495736 493741 491746 487759 488767 490772 494778 497782
      503788 508792 512793 516794 521792 526789 528785 533776
      536770 535766 536758 538759
 0.25 460240 460237 457236 454236 451236 448236 446236 443237
      440239 439241 441243 445244 447243 450243 453243 456243
      458242 460240
 0.25 456103 457098 457092 455085 456077 455069 452054 450039
      448021 447015 444007 440997 435999 431002 418022 414027
      412034 410041 408046 406047 401046 397047 396051 397055
      399056 404058 402064 398069 394069 391068 388076 385078
      382076 379072 376066 371062 368062 366063 368067 371071
      373079 373083 375086 384090 388090 391088 391086 396088
      399085 403080 408080 411085 411094 413097 412102 410104
      407104 404108 400110 388115 380122 379126 381128 387127
      392124 397122 408122 411119 418119 422119 423122 424126
      423131 422137 422140 424138 429122 430108 432102 434102
      437100 448098 453103 456103
 0.25 453086 452083 449081 448079 446077 444075 441074 441076
      441079 442082 444085 445087 449088 452088 453086
 0.25 318091 317088 317087 316086 315085 314085 312085 310085
      308087 308088 308089 308091 309093 310094 311094 313094
      315093 316093 317092 318091
 0.25 258799 256797 254797 251798 248800 246802 245804 243806
      241808 240811 242814 244813 247810 249809 250807 252805
      255804 257801 258799
 0.50 528761 528755 525749 521739 516732 511736 506745 504750
      501752 498757 498763 504769 511773 511776 514777 518776
      523773 521771 525767 528761
 0.50 468644 467639 463638 456639 448643 444649 443653 441656
      435661 422669 416674 412680 412683 414687 421686 438682
      453679 462676 468673 470668 469665 464657 464654 465651
      468644
 0.50 444041 444038 444036 443035 442034 440036 440038 441041
      443042 444041
 0.50 428087 429084 429082 428081 427080 426082 425084 426086
      428087 428087
 0.50 424055 423053 422048 422044 422040 421037 419036 417037
      415041 414043 413047 413050 411054 413057 416057 418056
      421057 424055

24HR QP VT 27/12Z
 0.01 535215 536208 536203 535193 530171 525165 519159 515155
      512157 509159 510162 511165 512167 510170 503168 497161
      495157 494150 493147 494144 498141 497138 493136 485131
      480126 476118 476109 473106 469105 466107 464111 467120
      467123 465122 463119 463124 465127 469131 470135 471139
      475140 478142 480145 478147 474147 465143 461143 457145
      454151 453156 456162 459160 462161 470170 473167 477165
      480169 481175 488188 490197 484200 476207 455218 442221
      432227 437231 442231 451225 460227 462230 462235 445238
      440242 432246 427250 423255 426257 430256 437253 445250
      453248 456249 459254 465258 471255 475257 476260 481268
      485277 489286 492290 496294 501293 505292 508289 513282
      516276 518271 520264 521260 522253 521248 518243 516237
      516231 518226 522224 525224 529225 533220 535215
 0.01 518077 519071 517067 513061 508057 501058 494059 491060
      489065 491071 493081 494084 496083 502079 505079 510080
      512083 515082 518077
 0.01 484863 487858 495850 496834 490812 484784 480777 470783
      452808 425844 390878 360896 329893 307870 295866 282871
      263884 257908 262924 275938 285951 283964 285981 290992
      300995 310989 324978 332985 331998 321013 303030 304039
      312047 311053 302059 295066 290075 281075 275072 265071
      258073 255074 255078 260085 261090 264092 271097 279099
      287100 291101 294103 303111 306113 311113 315110 326096
      335091 338083 336074 340067 348072 349084 354094 367100
      381102 389099 393101 392107 384116 378121 375129 380133
      389129 397121 407115 416115 420111 421105 420091 426069
      432036 441005 449978 460954 472923 477898 480889 483867
      484863
 0.01 440201 445208 449203 448202 448201 446199 446198 445196
      443195 441195 440194 438194 439197 440201
 0.01 422155 422152 423150 423148 423145 423143 421142 421143
      421145 420147 420149 419152 418152 418154 419156 420157
      422155 422155
 0.01 322036 322042 329041 337032 348018 347012 345009 343011
      336019 330027 324034 322036
 0.01 247810 255813 261816 270810 276811 273823 273827 283829
      295824 306821 314812 310799 305793 298790 288793 283794
      278792 269789 265790 261793 251797 246803 244808 245811
      247810
 0.25 511271 513266 514261 513256 512254 510251 507250 505250
      503252 502257 501259 499263 499269 500271 502274 505274
      507274 510273 511271
 0.25 396066 394064 393065 391066 389068 389070 390072 391073
      392073 394071 395069 396066 396066
 0.25 383054 383051 381049 379046 377044 375042 374042 372044
      370046 367048 366050 368052 370053 374053 377053 381055
      383054
 0.25 379080 381076 381072 380068 378066 375064 373064 370064
      368066 370068 372071 373073 374076 376080 377081 379080
 0.25 374947 373944 370941 365941 363938 361931 359927 355926
      349929 343934 332943 328947 323952 317956 312960 310964
      311966 319968 324969 332966 340966 345967 347969 350970
      353968 357963 362958 368953 374947
 0.25 312090 310086 308083 305080 299080 291081 287081 283080
      274077 270077 266078 270086 272089 276091 287092 298094
      303095 309094 312090
 0.25 300901 300891 299888 296886 290889 284893 280900 280908
      283915 286921 291922 294920 299914 300905 300901
 0.50 304089 302087 301085 299085 297084 296084 295084 294084
      292085 291085 292086 293087 294088 295088 297089 299089
      300090 302090 304089 304089


24HR QP VT 28/12Z
 0.01 518258 520238 519225 527217 533206 530177 518157 520140
      515131 506119 511113 517100 508078 487066 471039 463045
      463058 469077 470084 465087 460077 449066 439069 444076
      450084 446093 434095 417101 407124 411155 416225 420245
      435252 460255 465255 467257 474261 494283 498285 502286
      508280 513274 516267 518258
 0.01 357968 390947 418937 450914 487849 500772 491714 476672
      464656 453662 420738 383798 369798 350788 338800 330801
      321800 309807 305809 292807 288807 285805 279802 276797
      272794 266796 264798 264802 264807 266810 271814 279817
      286818 293818 300818 306820 312821 314830 298853 276877
      259897 256926 249953 246977 252988 261992 278991 301990
      325986 348975 357968
 0.01 493964 490982 490013 495053 501052 508023 505986 502975
      502970 501965 498957 496954 494957 493964
 0.01 472933 471944 469968 472982 479981 484968 485938 482932
      477924 475924 475930 472933
 0.01 418076 417069 412063 403062 401064 396064 391068 385072
      385079 389086 394090 403091 406089 410089 414085 418076
      418076
 0.01 316049 318036 316023 310015 309005 300002 287015 278036
      278040 279049 284059 290073 292092 300095 309078 316049
 0.25 511249 511241 509234 504224 502217 501210 502204 504197
      507192 509190 510184 510180 508177 505174 501170 498166
      495160 494153 489141 487136 484132 477124 472120 467120
      464125 462132 456142 452146 449148 439146 437147 436153
      439159 444173 444186 445192 450194 457189 460186 464181
      467179 473181 477183 483186 485189 486193 482198 479201
      477203 466209 449210 434211 432222 438233 452242 462245
      474248 486259 497271 501271 504270 505266 508261 511249
 0.25 502251 500245 498242 496238 493233 491229 487227 483227
      481231 483235 485239 488243 489247 494251 497253 500252
      502251
 0.25 477834 487791 487772 487758 486749 481728 478717 475710
      471704 468703 466707 463715 463720 465729 465751 459784
      449826 443852 444875 459871 477834
 0.25 447111 448109 447107 447106 446106 444105 442106 441108
      440109 439110 440111 442112 443112 445112 447112 447111
 0.25 385883 389864 385852 379843 369839 366838 356834 352832
      349829 345827 340826 337825 333827 325834 320841 307854
      302862 296868 285881 279890 275898 274903 268930 270950
      281968 289971 295971 299969 305964 320953 334943 342936
      347929 352922 359915 366908 372902 378895 383887 385883
 0.50 371887 373874 371864 363852 354848 348846 339841 327845
      323847 316851 311856 306861 285885 280899 276915 275930
      279948 284954 292958 300957 310950 320941 337922 340919
      346914 357905 363900 369894 371887
 0.50 496223 496215 494210 488206 482206 472210 467212 462213
      451215 446216 441219 443223 446225 449226 458232 463231
      467227 472225 476222 483223 488223 493226 495225 496223
 0.50 480241 480239 479237 478236 477235 476234 475235 474237
      475239 475240 477241 478242 480241
 0.50 486172 488165 487159 487155 485151 482148 480147 473142
      465141 461148 458155 457161 459164 465168 472171 478175
      482176 485174 486172
 0.50 477805 477802 477800 477797 477795 476794 475794 473795
      473796 472798 470801 470802 470803 469806 469808 470811
      471813 473814 474813 476810 476807 477805 477805
 0.50 459178 460175 460173 458172 456173 455174 454175 454176
      453178 452181 452183 453185 455185 456184 457183 457182
      459180 459179 459178
 1.00 485217 485215 482212 481211 479211 475212 474213 472214
      469215 467217 469219 472218 475218 477217 480218 483219
      485217
 1.00 350877 351872 350868 346869 337874 321863 313864 309867
      301872 293880 287889 284900 282906 282910 280926 283940
      286943 292943 296941 298939 307929 318918 321915 328907
      335899 342892 348884 350877
 1.50 324892 324887 322884 318880 311878 306878 299880 294885
      291889 289896 288903 284918 284930 286934 290938 293937
      296935 299929 305918 313908 321898 324892
 2.00 313898 313893 310890 302887 295893 291899 290910 288920
      288931 291932 294932 296928 300920 304912 310905 313898
 3.00 301907 299907 298910 299910 301908 301907

$$





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