FXUS04 KWBC 270959 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 458 AM EST MON JAN 27 2003 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID JAN 28/1200 UTC THRU JAN 30/1200 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR DAY 1... THE 0000 AND 0600 UTC GFS AND THE ETA RUNS WERE IN VERY GOOD AGREEMENT ON THE SYNOPTIC SCALE FCST FOR THE NATION. CHANGES MADE FROM THE PRELIM TO THE FINAL DAY1 MOSTLY REFLECT CURRENT OBSERVATIONAL DATA. ...ERN U.S... LGT SNOW WILL LINGER ACROSS NRN NEW ENG EARLY IN THE PD AS AN AMPLIFYING UPPER TROF AND ASOCTD ARCTIC FRONT SWING ACROSS THE AREA. LITTLE DIFFERENCE BTWN THE LGT MODEL QPFS HERE. ...GREAT LAKES REGION... A LGT WAA PCPN PATTERN WILL OVERSPREAD THIS REGION TODAY. TO THIS POINT IN TIME...THE MODELS HAVE BEEN OVERDOING PCPN AMTS WITH THIS SYSTEM AND HAVE CUT BACK ON AMTS FM GUIDANCE GIVEN LACKING PW AVBLTY. ...NRN CA EWD ACROSS THE GREAT BASIN TO THE N CNTRL PLAINS... PACIFIC ENERGY CONTINUES TO OVRRUN A FRONTAL BAND PRESSING SLOWLY SWD ACROSS THIS AREA. THE LAST OF THE MID LAT SHRTWVS PER LATEST STLT IMAGERY IS NOW NEAR 130W AND SHOULD MOVE ACROSS THE COAST BY THIS AFTN. THE ETA AND GFS QPF GUIDANCE IS IN RELATIVELY GOOD AGREEMENT ON THE AXIS OF PCPN ACROSS THIS GNRL AREA AND OTHER THAN DRAWING A BIT MORE FOR TOPOGRAPHY GNLY ACCEPTED THEIR SOLUTION. THE TETONS ARE FAVORED BY BOTH MODELS FOR THE HEAVIEST AMTS AS WLY FLOW PROVIDES STRONG OROGRAPHIC LIFT THERE. THE ETA IS NOT AS AGGRESSIVE AS THE GFS WITH SPREADING PCPN EWD INTO THE PLAINS AND BASICALLY COMPROMISED BTWN THE TWO SOLUTIONS ON SPECIFICS THERE. DAY 2... HEAVIEST PCPN IN THE LOWER 48 THIS PERIOD WILL BE THE RESULT OF A SHORTWAVE STREAKING EWD FROM THE UPPER MIDWEST INTO THE LOWER GREAT LAKES. THIS FEATURE WILL INTERACT WITH INCREASING WARM ADVECTION AHEAD OF A FRONT EXTENDING FROM THE LAKES INTO THE MID-MS VALLEY BY 60 HRS. MODEL PCPN TYPE ALGORITHMS INDICATE AT LEAST A LOW PROBABILITY OF 6 INCHES OF SNOW IN A BAND STRETCHING ACROSS NRN IN...NRN OH...INTO NWRN PA. REFER TO THE QPFHSD FOR MORE DETAILS ON THIS SNOW EVENT. LIGHTER AMTS OF SNOW WILL SPREAD INTO NY AND WRN NEW ENGLAND BUT LIQUID EQUIVALENTS SHOULD BE NO MORE THAN .15 INCH OR SO. FARTHER SOUTH THROUGH THE OH VALLEY AND POINTS SOUTH...PCPN WILL FALL AS RAIN. OTHERWISE...NOT MUCH IN THE WAY OF HYDROLOGICALLY SIGNIFICANT PCPN EXPECTED ELSEWHERE. PERSISTENT RIDGE ALONG THE SPINE OF THE ROCKIES WILL HELP TO SHUNT MOST MOISTURE INTO BC BUT THERE WILL STILL BE SOME LIGHT MEASURABLE PCPN SNEAKING INTO THE OLYMPIC PENINSULA. VERY LIGHT SNOW ALSO EXPECTED FOR THE NRN ROCKIES AND HIGHER ELEVS OF WY AND CO. DAY 3... PACIFIC NORTHWEST COAST GETS ACTIVE AGAIN WITH THE APPROACH OF A SHORTWAVE THAT BREAKS DOWN THE WRN RIDGE SLIGHTLY AND DRIVES A FRONT INTO THE NRN ROCKIES. WENT WITH A COMPROMISE SOLUTION IN THE OR COASTAL RANGES WHERE AT LEAST 1 INCH IS FCST. ERN U.S. FRONT PUSHES OFF THE NEW ENGLAND COAST WHILE HANGING UP OVER THE SOUTHEAST. LOWER MS VALLEY CAN EXPECT RAINFALL IN THE .50 TO 1 INCH RANGE PARTICULARLY OVER S-CNTRL LA...SRN MS AND S-CNTRL AL. LIGHTER AMTS FARTHER NORTH ALONG THE MID-ATLANTIC AND NEW ENGLAND COASTS WITH THE PASSAGE OF THE FRONT OFFSHORE. KORTY/MAUSSER GRAPHICS AVAILABLE ON THE WEB AT http://www.hpc.ncep.noaa.gov 24HR QP VT 28/12Z 0.01 493658 491653 489651 485649 478646 469644 462644 458644 452646 444650 433659 426667 418677 412687 410696 411701 414703 419703 423702 431700 441700 448702 457707 461707 466705 475700 485693 488682 491670 493662 493658 0.01 536216 536209 535205 531195 526178 524173 522168 517162 508156 507161 499161 490161 484163 483167 484171 488179 493185 499189 504191 507193 511199 521213 526218 532219 536216 0.01 521270 522264 521260 520254 516248 515244 512233 510227 507225 502215 500208 495204 490203 481204 478204 474206 468209 461207 459207 456210 455210 454206 455202 460194 468183 471176 475173 479166 481158 482151 482134 469120 473108 472103 470098 465093 462085 462073 462066 460059 457049 454039 452031 451014 448000 445989 442979 439969 435956 432946 431941 432936 456948 471955 483959 492961 498961 502960 512956 517949 520944 521938 521927 517916 517900 515887 513875 510870 509866 505862 503857 501851 499846 495837 487825 461798 455792 448787 436782 430779 422779 416782 410786 404801 405808 407814 411822 417832 420839 421845 421851 421855 414862 412866 411874 415882 424896 425902 425904 422904 415909 412917 413920 416924 421927 427933 425938 421943 418955 417959 416966 419993 420008 420021 417040 412045 406050 403053 399054 391060 386062 384064 386068 383071 377072 373075 375078 378080 382079 386079 387082 389087 390091 394101 395102 393105 387109 382115 380121 381128 386131 393131 395134 392138 387141 384146 384151 383153 378154 376155 378158 382159 386160 384164 382170 382176 385181 387183 377184 370183 365186 368193 373201 377206 381212 382215 380218 378219 375218 373216 370215 368217 369225 371233 373235 377239 389242 395246 400249 406250 413249 423250 426251 430248 436242 441237 443236 444240 452244 459244 466248 479259 491271 497278 499281 503284 508286 512286 516281 0.01 501251 500250 499246 498246 497245 498247 500251 500252 501251 0.01 487228 486228 483227 480225 477224 475224 472224 474227 477227 480228 482231 482231 483231 486229 487228 0.01 456232 456231 453230 452230 453231 455232 456232 0.01 419095 418091 418088 419084 418083 415082 412083 412083 412085 413087 414091 413095 415097 418097 419095 0.01 403098 404095 404091 404087 404087 403087 401089 400091 400094 398097 397098 398100 401100 403099 403098 0.01 312977 311971 310968 307962 303959 297955 293954 289955 287959 287965 291975 292983 288993 286997 286003 289006 294005 301001 306994 310987 312977 0.01 265975 265971 263969 263969 261966 260965 257964 257963 254963 251963 250965 249966 248968 247971 249974 250975 253976 253977 256977 259977 261977 264975 265975 0.25 499232 498228 497227 495223 495226 495228 496231 497233 499232 0.25 468157 469154 468151 467148 463140 459135 455133 451132 451138 448143 444142 442138 440136 438136 435139 433144 432152 433161 438165 448176 443190 453189 459183 460179 460176 457176 455174 454170 455164 458160 462158 468157 0.25 460110 461106 459102 458098 456092 453089 445093 435094 428091 426092 428096 429100 427103 424104 422106 421109 420111 415111 412110 409101 406104 404108 400109 397112 394113 396114 403120 405122 410123 418126 420130 422135 426131 431123 434120 437118 443121 445123 450123 452121 460110 0.25 446220 445219 443217 440216 437216 434215 431213 429212 428215 425218 425218 422222 424225 426227 426227 429230 432230 434229 435228 438226 439226 442225 444224 445222 446220 0.25 453080 453076 452072 451068 450067 447067 444065 443064 441063 439064 439064 436067 435068 436070 436072 439074 441075 442076 444078 447080 447080 450084 453080 0.25 446043 446039 445035 444034 441034 438034 436036 436040 438042 439044 441045 444046 446043 0.25 423238 422236 419234 417233 413234 413235 413236 416238 419238 422238 423238 0.25 425174 427172 427169 425166 423158 421148 417146 413146 406148 400152 399157 399162 399170 404176 408176 410175 414180 418185 421186 422182 425174 0.25 412227 414222 414217 412215 407214 405209 398198 391196 387194 380191 373190 373194 377199 385208 393214 403224 402227 397229 398233 401234 404232 409230 412227 0.25 410072 411068 410065 407066 404066 401068 401068 399072 398074 397076 398077 401076 401076 403072 404070 407071 408072 410072 410072 0.50 454155 453153 450152 447152 444150 444149 442147 440145 439143 437144 436147 435148 435152 435153 436156 438159 440161 443161 444162 446165 449164 449163 452159 452158 454155 0.50 453114 452108 454101 453097 451096 447097 439097 432100 430105 423107 424110 423114 420115 413113 408110 406109 404112 405115 409116 413120 417120 420119 423119 425122 429120 433116 438114 443117 448117 453114 0.50 400215 401212 400210 399208 397205 395203 394203 392202 389200 387198 386197 384196 381195 379196 380200 381200 383203 384204 386206 388208 391209 391210 394212 396213 398215 399216 400215 1.00 445109 444107 441106 439108 441109 444111 445109 24HR QP VT 29/12Z 0.01 553149 547137 543127 539122 532120 526116 521115 518118 516124 517130 518136 520144 521148 521153 516152 510148 506143 494135 483126 478123 474121 469122 460129 454132 448135 445141 445146 448154 452160 456166 455177 454183 455187 459187 462184 470174 475170 481168 488167 492167 496170 499172 501176 503182 504188 506192 510198 521211 526214 530216 535217 0.01 445942 444921 442904 443894 447890 454893 466910 473918 479929 488929 495909 493880 495846 499829 513793 516766 508737 490712 462708 432714 413725 401745 393768 376795 366805 359815 350826 344834 338843 328860 319879 313888 303916 301930 304943 308953 304963 298973 294982 294989 301991 313979 321969 340947 350946 359944 369931 378917 390913 397927 406959 416981 419985 424988 429987 434983 437979 440973 442966 444957 444950 445942 0.01 528245 523241 518234 512222 506211 503209 499208 494209 488211 482212 480219 478221 475221 470224 467226 465230 467248 469254 472260 480271 489283 492287 499293 510298 0.01 451072 447064 441056 436036 431031 426029 420031 414035 409041 403046 395053 390057 384063 380070 379073 380076 381080 387086 398087 403087 407086 414080 421076 428076 437078 442079 447078 451072 0.25 516282 520269 517258 515252 510246 503238 498237 493242 489247 488256 490266 494273 498280 502283 506285 514286 516282 0.25 394812 386829 377840 374844 364862 361883 364890 374886 383874 394864 401864 405875 408891 412912 418930 426926 425902 425863 425847 425823 430807 434789 429775 422773 411782 405789 403793 401798 394812 0.50 507278 506273 506272 504267 503267 501264 499262 496264 497269 497269 500273 501275 502277 505279 507278 0.50 411858 410862 412866 413867 415867 416865 416864 417861 417857 416852 416847 414846 413846 411852 411858 24HR QP VT 30/12Z 0.01 511678 508668 506662 503657 500656 498653 495647 495640 492633 488625 483620 476617 466616 460616 454619 450621 444625 438630 433635 428641 425648 424655 424665 423672 417678 411684 407691 404696 401702 394712 391718 387722 379733 367735 356730 348735 344741 338753 329775 322795 306843 300864 294886 293898 292913 292929 290944 291955 292961 295966 297972 300976 306977 310976 312974 315969 317962 318956 321949 337930 345920 351911 362894 369883 374871 380858 385852 388845 396834 403825 412824 421816 426811 429809 431810 432815 432821 431829 427836 422842 417848 414853 413860 416865 418868 420868 425870 432869 436870 448865 455865 460872 462881 461892 462904 466909 472906 480896 486881 488875 488870 488858 485849 483845 474830 471822 470813 472805 476797 483782 490768 496757 500749 502743 504737 505730 509701 509696 511689 511678 0.01 525251 517236 512225 518225 524227 528228 533224 538216 539210 539203 537192 535185 533180 528174 527171 514157 498142 487130 479120 475114 472109 470102 465098 462095 455093 450091 442089 435088 429088 423090 415096 407106 404111 403117 406121 412127 414133 413141 406151 403155 402158 403160 409163 411166 413172 415177 418184 417189 413195 410204 409211 407215 402218 398223 397227 397234 399241 401247 408254 415258 421260 428262 435263 447266 459269 472276 507299 0.01 371791 375786 380777 381773 377775 372781 367791 368792 371791 0.01 419072 418066 415062 412060 407058 402057 398056 395057 393061 394064 396068 399072 403076 407078 412079 417076 419072 0.25 494677 493674 491674 488675 485676 483679 482683 485684 487684 488684 491684 494681 494677 0.25 490276 502286 511287 517280 519266 517253 510235 503215 499209 494206 480203 475205 470206 462205 456204 449202 443204 435209 429212 425218 421224 418227 413228 409229 408235 410241 413247 418251 426254 433255 439255 452256 463259 475265 487274 490276 0.25 456188 464181 464174 466169 476170 490179 504196 519211 526215 530209 525194 514181 498173 487166 479155 474147 468142 465141 460141 450148 444150 440149 435154 434160 437166 441173 443190 448194 456188 0.25 379820 376814 372814 369816 359826 351833 346836 342836 338831 337826 340813 343803 347792 352780 357768 358761 357756 354755 351759 345771 343777 342784 340789 338793 330802 322826 315846 312856 308868 303890 301902 300917 299929 300938 302940 305942 309940 311938 314934 317927 326908 342872 351864 356864 361861 364855 371841 376830 379820 0.50 509274 509267 509262 510256 510250 508243 502229 496218 492215 485212 479211 473211 469211 462211 453210 446211 441212 432216 427223 422231 417235 415239 417245 425250 441251 449251 461252 470253 477256 481258 489265 499276 504278 508277 509274 0.50 323900 331877 333856 331844 328839 323841 320848 316856 313864 312871 310881 308887 304903 304913 305923 307928 312925 316920 322905 323900 1.00 444243 453241 458239 460236 458233 455229 456226 457223 457220 453217 449217 444217 440218 435221 432224 430228 430234 431238 436243 442244 444243 1.50 443231 448230 451228 451224 451222 450221 449220 442221 438225 437227 439229 443231