FXUS04 KWBC 241843 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 242 PM EDT TUE APR 24 2012 PRELIM DAY 1 QPF DISCUSSION VALID APR 25/0000 UTC THRU APR 26/0000 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR DAY 1... ...NERN U.S... VRY COLD AIR ALOFT ASOCTD WITH THE WKNG ST LAWRENCE RIV VLY CLOSED UPPER LO WILL CONTINUE TO FIRE SHWRS OVR THE NORTHEAST. ...UPR MS SEWD THRU THE OH VLY TO THE SRN APLCNS... PIECES OF SHRTWV ENERGY EMBEDDED IN NWLY FLOW WILL SUPPORT AREAS OF WEAK ISENTROPIC IN THE STRONG BAROCLINIC ENVIRONMENT ON THE BACKSIDE OF THE SLOWLY EXITING ERN U.S. UPPER TROF. IN GNRL..MODELS QPFS SUPPORT ONE MAXIMA INVOF THE MID OH VLY SEWD TO THE SRN APLCNS THIS EVNG AND TNGT..WHILE IGNITING ANOTHER FM THE UPPER MS VLY SEWD TO THE MIDWEST OVRNGT INTO TMW. THERE ARE SGFNT MODEL QPF DIFFERENCES WITH PLACEMENT..WITH SGFNT CHANGES NOTED WITH THE SAME MODEL FM RUN TO RUN MORE THAN LIKELY DUE TO THE LIMITED MSTR AVBLTY AND WEAK UPPER LVL FORCING INVOLVED. THE UKMET SEEMS TO HAVE THE BEST RUN TO RUN CONTINUITY OF THE MODELS AND FOR NOW OPTED FOR THE UKMET FOR PLACEMENT..BUT UPPED AMTS WITH THE UPPER MS VLY SYSTEM BASED ON HEAVIER ECMWF/GFS AMTS AND/OR COVERAGE. ..THE WESTERN U.S... SPLIT FLOW WILL AFFECT THE WRN U.S. THRU THE FCST PD WITH THE VORTEX DROPPING TO A PSN OFF THE VRISL BY WED MRNG BRINGING STRONG ONSHORE FLOW AND HGT FALLS TO THE PAC NW BY TNGT. THE UKMET/GEM REGIONAL/GFS ARE SIMILAR WITH THEIR QPFS OVR THE PAC NW WITH LAST NIGHTS 00Z ECMWF THE OUTLIER..BEING SOMEWHAT SLOWER AND DIRECTING MOST OF ITS ASOCTD QPF ACROSS VRISL INTO BC. LATEST STLT IMAGERY WOULD SEEM TO SUPPORT THE FASTER AND HEAVIER SOLUTION OVR THE PAC NW AND LEANED IN THAT DIRECTION FOR THE MOMENT. MEANWHILE...JUST THE OPPOSITE IS TRUE OVR SRN/CNTRL CA WHERE THE ECMWF IS ARGUING FOR HEAVIER AMTS AS COMPARED TO MOST OTHER GUIDANCE. LATEST STLT IMAGERY DOES SHOW SUBTROPICAL MSTR AT LEAST AT MID TO HI LVLS STREAMING NEWD AHEAD OF A MID LATITUDE SYSTEM WORKING EWD TOWARDS THE SRN CA COAST. FOR NOW..IT APPEARS THAT THIS SYSTEM SHOULD STAY FAR ENUF OFFSHORE TO SOMEWHAT LIMIT AVBL UPPER LVL FORCING AND LLVL ONSHORE FLOW THRU THE END OF THE PD. FOR THIS REASON AND GIVEN THE HUGE MODEL DIFFERENCES..OPTED TO BLEND AVBL MODEL GUIDANCE USING THE UKMET/ECMWF FOR PLACEMENT PURPOSES. MEANWHILE TO THE NORTH AND EAST OVR THE GREAT BASIN..AGAIN USED A BLEND OF GUIDANCE WHERE THE ECMWF SHOWED FAR LGTR TOTALS THAN BOTH THE UKMET AND GFS. KORTY GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 26/00Z 0.01 524256 521248 518237 515228 511219 512214 514213 519214 532220 535208 534196 526184 522179 521171 521161 519153 513132 506114 502109 498109 495112 493116 490121 490128 490135 491140 494147 497153 494158 484156 478152 474150 470145 467144 462141 460140 457142 453147 449148 446146 444142 444137 446135 448131 451125 457122 462109 464104 464099 463094 462089 461081 461075 460070 455055 447036 444029 440023 436026 431031 425045 415044 413048 414052 413057 412058 409062 414066 419069 423076 424079 424084 421092 418092 416089 414087 412084 410084 406087 404091 402097 401102 399103 393107 385113 376121 373125 373129 374130 377130 379128 385123 387123 391120 396122 400123 402125 408130 410133 409135 407137 403142 399149 395154 385160 382162 380164 378169 373172 368174 355176 351175 346168 344166 339164 336166 335169 333180 329183 318189 312192 308196 300203 296206 295213 297216 303220 314218 329217 342216 347217 353219 361214 361211 358206 356203 356199 361195 366197 369202 382211 385214 389216 387218 382219 376222 368222 365225 369231 375235 386242 394250 403259 408265 411273 412281 413290 416291 424291 431291 437289 440291 443294 447295 460297 471296 481293 489293 499295 504295 511292 0.01 485700 480690 475679 472676 469676 465678 461683 451690 444699 440704 436712 413739 409745 408749 403755 399761 397768 400771 404771 413765 418761 421758 425757 426760 425765 424768 421772 419776 417778 416782 414789 413793 414796 417800 421800 425796 429789 433788 437784 443783 446784 450786 453785 457786 459785 465781 466776 467772 465769 463765 459762 455760 449755 449750 453744 458738 465731 473725 483712 486705 485700 0.01 505901 504897 501889 496885 492884 490882 484875 474867 463859 455854 449851 442850 436847 425840 414834 407830 400827 394826 386827 381823 378817 374810 371802 368796 365791 362790 359792 355794 351792 347792 344795 343802 345812 345824 345831 347837 350848 352853 353858 353864 356868 360873 366878 376880 381888 383893 386894 388893 393888 395887 396890 398902 400909 402919 402928 401931 400936 400942 402947 406954 411953 414950 416948 421943 423939 424934 426929 428927 431928 432931 433936 431941 428947 425956 423966 423975 423982 426987 432987 436984 438981 440975 443966 450973 456972 462975 470987 479991 483992 488990 493982 498982 504980 505977 505972 503957 501949 505923 506915 506906 505901 0.01 486187 487183 485182 483178 480177 477181 476185 476190 479191 482191 485189 486187 0.01 467200 466196 462192 458193 456195 451198 448198 446203 442204 440201 437193 442179 445175 442171 437164 434159 431152 433141 438134 440129 440123 438120 435119 433122 430130 428140 428151 426159 428163 428169 427180 425184 420185 416181 414177 413176 409175 405179 400181 394187 395193 398199 404202 418201 421200 425202 430205 435209 438207 442209 446212 453210 467200 0.01 414130 414129 411127 409129 411133 414130 414130 0.01 384940 384932 383925 382921 380920 377923 370930 364937 360945 364955 361966 360970 360977 361984 365984 371979 376971 380962 382955 383951 384940 0.25 517278 519274 521269 520262 516253 514243 512234 506226 502217 498209 492207 483207 476210 471213 469215 464215 456219 453221 448219 444218 440218 439223 439226 439230 437234 435238 433240 430239 423234 418232 413228 413219 409217 407218 405222 405228 402234 398234 395235 394237 395240 399244 403247 408248 419249 426247 432246 436247 439251 445258 454261 457262 459263 459266 458272 460277 492281 502287 506288 509287 517278 0.25 491920 491915 490911 489907 488905 485904 482906 481909 480912 479915 477916 475919 472921 476924 479928 482931 483933 486935 488931 489929 490924 491920 0.25 467944 467940 465936 464933 461927 461924 463922 465919 463915 461912 455905 450895 446888 440882 434878 421871 418868 415867 414869 413872 412878 412882 410887 409892 410898 413904 415900 419897 424896 430900 435907 440917 443925 457937 462945 465945 467944 0.25 382854 381848 380844 376837 373831 369825 364820 361817 358818 357826 358833 362839 366845 370852 376856 379857 382854 382854 0.50 516272 517264 516260 513252 509234 503226 500219 497215 493215 485213 482213 480218 485223 488227 489230 489234 485235 476230 470233 465233 463235 462239 466243 471248 474255 476260 478264 482268 496278 505283 507283 510279 516272 0.50 447907 446903 445899 442899 442901 443903 444904 446907 446908 447907 1.00 508264 510259 510254 510249 508241 506236 501228 498223 495223 493226 493230 494236 493240 487239 484241 476237 475240 477244 483254 489264 497272 500274 503274 505272 506268 508264 1.50 507249 507247 506244 505241 504239 503236 500234 499232 497230 497231 497233 498236 499240 500242 501245 504247 504248 506251 507249 1.50 497264 499260 498255 497252 496250 495249 492245 491243 490242 487241 487242 485246 486249 486251 488254 490256 490258 493261 494263 495264 497264 $$