Quantitative Precipitation Forecast
Issued by NWS

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000
FXUS04 KWBC 301850
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
249 PM EDT WED JUL 30 2014


PRELIM DAY 1 QPF DISCUSSION
VALID JUL 31/0000 UTC THRU AUG 01/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1...


...GREAT LAKES/OH VALLEY/NEW ENGLAND....

SHORT WAVES RIDING THROUGH THE MID LEVEL LONG WAVE TROUGH CENTERED
ACROSS ONTARIO AND QUEBEC WILL PROVIDE SYNOPTIC SCALE LIFT AHEAD
OF AND ALONG A FRONT MOVING THROUGH THE OH VALLEY...GREAT LAKES
AND NEW ENGLAND. THROUGH THIS EVENING...ACTIVITY AHEAD OF THE
FRONT WILL TAKE ADVANTAGE OF MARGINAL INSTABILITY AND PRECIPITABLE
WATER VALUES NEAR 1.00 INCHES TO PRODUCE SCATTERED CONVECTION
ACROSS OH...WESTERN AND NORTHERN PA INTO WESTERN AND NORTHERN NY
STATE. THE CONVECTION SHOULD SUPPORT AREAS OF 0.10 TO 0.25 INCHES
OF QPF...BUT LOCAL AMOUNTS NEAR AN INCH ARE POSSIBLE WITH STRONGER
CONVECTIVE CELLS THROUGH ABOUT 31/02Z.

WHILE ACTIVITY COULD REMAIN VIABLE ACROSS WESTERN AND NORTHERN NY
STATE INTO VT OVERNIGHT...THE ACTIVITY BECOMES REJUVENATED AFTER
31/15Z. A 20 KNOT LOW LEVEL JET PUSHES PRECIPITABLE WATER VALUES
NEAR 1.10 INCHES INTO CENTRAL AND EASTERN NEW ENGLAND AHEAD OF THE
COLD FRONT AND THE STRONGEST SHORT WAVE IN THE LONG WAVE TROUGH
ACROSS THE NORTHEAST. CONVECTION SHOULD BECOME MORE WIDESPREAD IN
THE AFTERNOON ACROSS NORTHERN NEW YORK STATE...VT...NH AND THE
WESTERN HALF OF ME. LINES OF CONVECTION IN THE BEST LOW LEVEL
INFLOW SHOULD PRODUCE LINE OF 0.25 TO 0.50 INCHES OF QPF IN THE
HIGHER TERRAIN OF THEE LOCATIONS...WITH 0.50 INCH AMOUNTS POSSIBLE
IN THE MOUNTAINS OF WESTERN ME.


...FL...

CONVECTION AHEAD OF AND ALONG A COLD FRONT WEAKENING AND SLOWING
AS IT MOVES INTO CENTRAL FL WILL BE THE PRIMARY QPF DRIVER THROUGH
THIS EVENING...AND AGAIN THU AFTERNOON AND EVENING. THROUGH THIS
EVENING...LINES OF CONVECTION SHOULD BE TIED TO THE FRONTAL
POSITION ACROSS CENTRAL FL...WITH MORE SCATTERED ACTIVITY ACROSS
SOUTHERN FL. MODERATE INSTABILITY AND PRECIPITABLE
WATER VALUES NEAR 2.00 INCHES SUPPORT A WIDESPREAD AREA OF 0.25 TO
0.50 INCHES OF ACROSS THE SOUTHERN THIRD OF THE STATE.

CONVECTION REDEVELOPS AHEAD OF THE FRONT ACROSS SOUTHERN FL LATE
THU MORNING AND EARLY THU AFTERNOON IN A MODERATELY UNSTABLE
AIRMASS WITH PRECIPITABLE WATER VALUES NEAR 2.00 INCHES. A WEAK
MID LEVEL TROUGH WEST OF THE PENINSULA COULD AID CONVECTIVE
DEVELOPMENT IN THE FORM OF BETTER SYNOPTIC ASCENT....AND POSSIBLY
GREATER CONVECTIVE COVERAGE. ONCE AGAIN...THE BEST CONVECTIVE
POTENTIAL LIES JUST AHEAD OF THE FRONT (OR TROUGH...AS THE FRONT
BECOMES HARDER TO FIND). TOTAL DAY 1 QPF VALUES COULD REACH NEAR
AN INCH ACROSS SOUTHERNMOST FL AHEAD OF THE FRONT BY 31/00Z.


...SOUTHERN PLAINS/LOWER MS VALLEY...

THE ACTIVITY DRIVEN BY THE MCV OVER NORTH CENTRAL OK HAS
DIMINISHED IN COVERAGE AND INTENSITY AS THE AIRMASS HAS YET TO
RECOVER FROM A CONVECTIVE STANDPOINT...EVEN IN THE PRESENCE OF
PRECIPITABLE WATER VALUES NEAR 2.00 INCHES. THE MCV SHOULD REMAIN
THE DRIVING FORCE WITH RESPECT TO LIFT...AIDED BY WEAK SHORT WAVES
DROPPING OUT OF THE ROCKIES INTO THE SOUTHERN PLAINS AFTER 31/00Z.
THERE IS A MULTI MODEL SIGNAL THAT THE LOW LEVEL SOUTHERLY FLOW
BECOMES REINVIGORATED AFTER 31/0Z AS A 25 TO 35 KNOT LOW LEVEL JET
POINTS TOWARD EAST CENTRAL OK AND WEST CENTRAL AR. PRECIPITABLE
WATER VALUES REMAINS BETWEEN 1.75 AND 2.00 INCHES ON THE NOSE OF
THE LOW LEVEL JET...AND THE NAM SIMULATED IMAGERY SHOWS ANOTHER
MCS DEVELOPING ACROSS EAST CENTRAL OK AFTER 31/03Z. IT REACHES
PEAK INTENSITY NEAR 31/09Z IN EASTERN OK AND STARTS TO DIMINISH
WITH THE LOSS OF THE LOW LEVEL JET BEFORE 31/15Z.

THERE IS A STRONG SIGNAL FOR A SWATH OF 2 TO 4 INCHES OF QPF IN
THIS AREA...WITH A PEAK NEAR 3.50 INCHES ACROSS WEST
CENTRAL AR. THERE WERE ALSO A NUMBER OF 12Z GEFS MEMBERS SHOWING
THE POTENTIAL FOR 4+ INCHES IN EAST CENTRAL OK AND WEST CENTRAL
AR...SO A MODERATE RISK WAS RETAINED HERE. IT WAS SURROUNDED BY A
SLIGHT RISK FOR THE REMAINDER OF EASTERN OK AND WESTERN AR.  AS
WAS THE CASE THIS AFTERNOON...THE CONVECTION WANES AS THE RAIN
COOLED AIR AHEAD OF THE MCV TRIES TO SUPPRESS ADDITIONAL ACTIVITY.


...CENTRAL/SOUTHERN ROCKIES...

THE AIRMASS ACROSS CENTRAL AND WESTERN CO IS STARTING TO RECOVER
AFTER THE ACTIVITY OF LAST NIGHT AND THIS MORNING...AS MLCAPES
INCREASE IN THE PRESENCE OF WEAK UPSLOPE. THE REJUVENATION OF THE
AIRMASS COULD SUPPORT CONVECTION THIS AFTERNOON INTO THE EVENING
HOURS...AND THE WATER VAPOR LOOP SHOWS AN APPROACHING WEAK SHORT
WAVE. THE COMBINATION OF SYNOPTIC SCALE ASCENT...MARGINAL
INSTABILITY AND PRECIPITABLE WATER VALUES AROUND 1.10 INCHES COULD
RESULT IN LOCAL 1 INCH QPF AMOUNTS... MAINLY BEFORE 31/03Z. ONE
AND THE HOUR FLASH FLOOD GUIDANCE VALUES HERE ARE AS LOW AS 0.75
INCHES...DUE TO EARLIER HEAVY RAINFALL...SO A SLIGHT RISK WAS
RETAINED FOR THE ROCKIES IN CO AND FAR NORTHERN NM. AFTER
03Z...HIGH RESOLUTION MODEL OUTPUT SUGGESTS THAT THE THREAT
DIMINISHES DUE TO LOSS OF MOISTURE AND INSTABILITY.

THE MOISTURE AND INSTABILITY CONTINUES TO WEAKEN OVERNIGHT...BUT
THE ACTIVITY MAY NOT COMPLETELY DIE OFF THE TERRAIN.
MARGINAL INSTABILITY IN THE FORM OF STEEPENING MID LEVEL LAPSE
RATES AND PRECIPITABLE WATER VALUES BETWEEN 0.75 AND 1.00 INCHES
COULD AGAIN FUEL CONVECTION TIED TO THE TERRAIN STRETCHING ACROSS
CO INTO NORTHERN NM. THE ADDITIONAL CONVECTION COULD PRODUCE AREAL
AVERAGE QPF VALUES NEAR 0.50 INCHES...ESPECIALLY FROM CENTRAL CO
INTO NORTHERNMOST NM. WHILE THE ONE AND THREE HOUR FLASH FLOOD
GUIDANCE VALUES REMAINS FAIRLY LOW...IT IS NOT YET CLEAR THAT THE
COVERAGE OF THE CONVECTION THU AFTERNOON AND EVENING WILL SUPPORT
A SLIGHT RISK AREA.


...GREAT BASIN/NORTHERN ROCKIES...

A PRECIPITABLE WATER PLUME OF NEAR 1.30 INCHES STILL STRETCHES
FROM NORTHWEST UT INTO SOUTHEAST ID AND WESTERNMOST WY...IN THE
PRESENCE OF MLCAPES IN THE NEIGHBORHOOD OF 1000 J/KG. THE SHORT
WAVE MOVING ACROSS SOUTHWEST WY COULD PROVIDE SYNOPTIC SCALE LIFT
ACROSS THIS REGION DURING THE AFTERNOON AND EVENING
HOURS...SPARKING SCATTERED CONVECTION. THE ONE HOUR FLASH FLOOD
GUIDANCE VALUES ARE CLOSE TO AN INCH...ESPECIALLY IN THE TERRAIN
OF WESTERN WY AND NORTHERN UT. WHILE MOISTURE REMAINS IN
PLACE...THE ACTIVITY SHOULD REMAIN WIDELY SCATTERED AND TIED TO
THE TERRAIN. BECAUSE OF THE LACK OF COVERAGE...THIS AREA WAS
REMOVED FROM THE SLIGHT RISK AND PLACED IN A SEE TEXT...MAINLY FOR
ACTIVITY THROUGH 31/03Z.

THE ACTIVITY SHOULD WANE AFTER 31/06Z DUE TO LOSS OF SURFACE BASED
CAPE. LESS IN THE WAY OF FORCING ON THU SHOULD RESULT IN WIDELY
SCATTERED COVERAGE ACROSS THE GREAT BASIN AND NORTHERN ROCKIES.
LOCAL BOUNDARIES WILL ACT AS FOCI FOR CONVECTION AS WELL. MARGINAL
INSTABILITY AND PRECIPITABLE WATER VALUES CLOSER TO 0.75 INCHES
SUPPORT LOCAL 0.10 TO 0.25 INCHES OF QPF ACROSS THE HIGHER TERRAIN
OF THE THE SIERRA NEVADA RANGE IN CA...THE HIGHER TERRAIN IN EAST
CENTRAL NV...AND THE SOUTHERN CASCADES IN OR.


HAYES

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



24HR QP VT 01/00Z
 0.01 553848 549841 548837 547830 540809 536784 534772 532760
      530747 529744 528737 526723 524717 523709 519704 514701
      510697 507696 500693 489685 483682 476678 472677 470679
      462684 448692 435700 428705 421711 408723 399735 394741
      392748 394752 398752 403751 405755 390784 387792 388801
      389808 390813 392826 392832 394837 395847 400869 400874
      402878 402889 410908 412912 415914 418917 422917 429916
      432913 433909 434906 434902 436899 436895 437890 439885
      443883 447882 449879 449874 447872 442873 439875 437873
      437869 436865 438862 447861 454863 456864 460865 467868
      478868 480866 482869 488872 500884 505889 507890 511891
      520890 524889 529886 536874 544868 549863 552855 553848
 0.01 504122 504114 503110 502103 499099 492094 488092 482092
      478091 475093 463091 456085 451077 447070 443067 437066
      434068 432073 436074 438074 441077 444077 446078 447081
      445088 441086 431085 427085 423088 421091 416092 409092
      401096 396096 393098 392100 393105 396110 400112 403116
      407119 409118 415119 418121 423122 427122 432119 435116
      438114 441115 441117 440125 436133 434137 433146 434150
      437155 442161 452164 459160 464151 470155 484147 488147
      492142 491139 493135 496131 500129 504122
 0.01 478032 478024 478019 473011 465006 458003 449003 444005
      443007 442019 447027 454032 457035 462036 472036 478032
 0.01 459178 461171 460167 455166 451168 446178 444181 443184
      441184 427172 422166 418158 415149 411138 408131 405126
      402123 397117 389113 383113 380114 375121 375127 376131
      374146 374157 372162 372168 361177 359181 355184 362187
      375198 390208 393209 397208 399202 403200 411203 415205
      415210 415217 416220 420224 424227 428228 432228 439226
      444219 446215 448206 448199 447194 447190 451189 456183
      459178
 0.01 423651 421647 417645 410644 405647 402650 394658 390660
      387663 378667 368671 358676 352683 346688 331702 325709
      317715 313718 310720 303725 295731 290736 288741 286745
      284750 280754 269765 263773 257780 251786 247792 237809
      234818 231828 229836 228840 228846 229858 231867 231875
      233879 234886 236890 244905 248907 251904 255905 260905
      263903 266899 266889 265878 264865 264851 264845 265841
      268837 271835 274832 278829 289827 299826 306826 310828
      317834 320837 323842 329846 331846 334848 337850 341852
      347851 354846 359841 362830 362823 360817 347808 344803
      344797 343789 342783 334780 332778 332775 333770 335758
      339749 347733 360718 365712 371706 387691 400678 413666
      419658 423651
 0.01 414061 415056 415049 412041 408033 405029 401026 387028
      384028 382026 377026 374027 372032 370035 365036 361041
      355040 353038 347029 343028 342026 343024 349021 351017
      356016 361018 367019 370018 372015 375006 379982 382970
      383958 382952 381949 379940 367900 362894 359891 355889
      351888 346888 342888 338890 332894 326899 322900 318904
      312910 309912 306916 304923 301933 301945 301951 299955
      299966 297970 297976 295982 292986 282001 278007 276011
      276015 282054 280057 277060 268063 257062 251061 244064
      242073 248081 254086 271095 283104 285106 290108 293110
      298110 304111 309110 316106 321104 327105 337107 344111
      347112 351111 355111 359109 362107 363104 365099 366091
      368086 372084 376084 380086 389086 395087 402083 409071
      414061
 0.01 323029 323018 323007 324002 322997 320990 319988 316989
      315992 312000 310009 309019 309030 311033 315035 318035
      320033 323029
 0.25 537856 536855 534855 532854 531853 529853 528853 526853
      524854 523855 524857 525858 526859 527860 528860 530861
      531861 533860 534859 536857 537856
 0.25 521847 521838 520832 512821 511816 512807 512799 510791
      502763 500754 502745 503737 503731 499719 496712 493705
      489701 484699 475695 466694 459695 453698 443706 435713
      430723 427729 427732 427737 429757 428763 426768 415790
      415798 417807 422810 426808 430797 433790 436785 452767
      456764 462764 467767 471772 473775 472780 471787 468799
      465812 467819 471824 475827 479832 477835 476842 478848
      481852 491858 496860 501860 507861 513859 519853 521847
 0.25 437100 436098 436097 435100 436100 437100
 0.25 404172 404167 403162 401157 399154 394152 388153 386157
      384161 385166 388169 391172 396174 402174 404172
 0.25 406058 404053 401049 392044 386044 381045 371046 362052
      359055 358058 359060 363065 367068 376073 380074 385073
      389071 394070 398068 400062 405060 406058
 0.25 384678 384675 381674 377677 368684 352695 345701 337709
      330715 323723 319730 313738 300752 293759 287767 271777
      265783 259792 253798 250802 249808 250815 249819 250822
      252824 257825 263825 268823 276817 285800 296784 297775
      300770 304766 318752 331739 344726 358711 364704 371697
      380688 384678
 0.25 370956 369944 368932 364921 359912 354905 350902 344902
      339904 336907 332916 325935 321945 319950 319956 319960
      322965 327967 332967 336969 338975 341984 342989 345994
      349996 353996 361991 365988 367983 370971 370957 370956
 0.25 309043 309041 308038 306036 302035 301037 299040 299044
      299048 300050 301053 303053 305051 307049 309045 309043
 0.25 300084 298079 293075 287074 282074 275075 271079 272083
      273085 277088 282091 287093 294094 297090 300084
 0.25 255870 255864 255858 254852 250855 247859 245861 243865
      243871 244877 246881 249884 252885 254881 255877 255872
      255870
 0.50 503806 500803 497804 492806 489808 484811 482814 481818
      485820 489818 493815 496813 499811 502807 503806
 0.50 494717 491712 490711 487713 481712 476708 472705 465703
      458705 451708 446712 446717 448717 455718 460719 468719
      471720 473723 470731 470741 473749 476750 479750 485747
      490742 494736 494726 494717
 0.50 439772 439770 438768 437770 436770 437772 437773 439773
      439772
 0.50 402056 400055 400056 402056 402056
 0.50 397055 394052 390050 385052 380051 376052 372055 371059
      375062 380062 386062 389060 393058 397055 397055
 0.50 352706 350706 348707 345710 343710 341713 339716 337717
      336720 336722 339720 341719 343717 345714 347712 349710
      350708 352706
 0.50 366976 367971 368964 366952 365942 363932 360924 356916
      351910 345908 341910 339912 335920 333929 331939 328947
      327952 328956 335962 339968 342977 346984 352988 356987
      360985 364981 366976
 0.50 273810 272805 268802 265802 259803 256804 254808 255812
      257815 261818 266819 268818 271815 273811 273810
 1.00 363969 364961 364952 363944 361938 359932 356925 353921
      349917 344917 341922 339923 337928 336934 335941 335949
      337955 341960 346971 348976 353980 359976 362972 363969
 1.50 361965 362958 361952 361945 359941 356932 352924 348922
      344923 341927 339932 339943 341952 346960 350968 353971
      357972 360969 361965
 2.00 359958 359952 358943 355936 353931 350926 346926 344928
      342934 342943 344949 346955 350960 353965 357964 359958
 3.00 354949 354947 354945 354943 354941 354939 353938 352936
      352935 351934 350933 348934 347936 347939 347941 347943
      348945 348947 349947 350949 350950 352952 354951 354949

$$





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