EXCESSIVE RAINFALL DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
945 AM EDT THU APR 29 2010
 
...VALID 15Z THU APR 29 2010 - 12Z FRI APR 30 2010...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...
 

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
10 NNW HJH 15 WSW FET 15 N FET 25 NNE TQE 25 NW DNS DNS ICL
25 NNW TOP 40 WSW CNK 10 NNW HJH.

 
15Z UPDATE...
EXPANDED EARLIER OUTLOOK SLIGHTLY NWWD BASED ON CURRENT FFG ACRS
ERN NEB..OTHERWISE NO CHANGE TO PREVIOUS FCST RATIONALE.  LATEST
U/A AND GOES SOUNDER DATA INDICATE SOME GREATER THAN 1 INCH PWS
EXPANDING NWD THROUGH S TX WITH A NARROW RIBBON EXTENDING AS FAR
NORTH AS CNTL OK.  THIS IS SLIGHTLY WETTER THAN 06Z NAM/GFS AND
00Z ECMWF PW FCSTS AND SUPPORTS THE IDEA OF EXPANDING FF SLIGHT
RISK THREAT.  SULLIVAN

...NERN KS/SERN NEB/SWRN IA/NWRN MO...
DEEP VORTEX OVR MT WL MOV SLOLY EWD THIS PD WITH A DEEP/BROAD TROF
DVLPG OVR THE WRN U.S. AS SVRL SHRTWVS DIG INTO THE WRN U.S.. SVRL
SHRTWVS ARE SEEN IN THE GUID LIFTG NNEWD LATER TDA/TNGT INTO/ACRS
THE CNTRL U.S. THAT WL PROVIDE SOME HGT FALLS...ESPCLY LATER TNGT.
UPR FLOW WL BCM SOMEWHAT DIFL WITH MDLS SHOWG SVRL SMALLER SCALE
UPR JET STREAKS THAT WL PROVIDE PDS OF STGR UPR DVRG. CDFNT THRU
THE PLNS WL BCM ORIENTED PARALLEL TO THE MID/UPR FLOW THAT WL
SUPPORT CNVCTN TRAING TWD THE NNE. DEEP LYRD FLOW IS FCST TO INCRS
THRU THE PD WITH AN IMPRSV LLJ DVLPG TNGT. 8H WNDS IN EXCESS OF 50
KTS ARE FCST BY ALL THE GUID. THIS WL BEGIN TO TAP INTO A POOL OF
VRY HI PWS OVR THE WRN GULF...WHERE PWS ALNG THE NRN YUCATAN ARE
ALRDY AOA TWO INCHES. MDLS SHOW PWS INCRSG TO ARND ONE INCH LATER
TDA AND PSBLY 1.50 INCHES BY THE END OF THE PD AS MSTR POOLS ALNG
THE BNDRY. THE VRY STG LOLVL FLOW COMBINED WITH DEEP MSTR WL
SUPPORT AN ANOMALOUS RIBBON OF 8H MSTR FLUX WITH ANOMALIES RISG TO
ARND 4 STDS ABV NRML BY LATER TNGT. XPCT CNVCTN TO FIRE OVR NCNTRL
KS LATER THIS AFTN NR A WEAK SFC LOW ALONG THE FNTL BNDRY...THEN
EXPAND TNGT EWD INTO THE MOIST AXIS. RNFL RATES INCRSG TO 1-2
INCHES PER HR WL BE PSBL LATE TNGT WITH ISOLD HVIER TOTALS WHERE
TRAING OCCURS. LATEST EXPERIMENTAL HI-RES DENSITY PLOTS OF RNFL
EXCEEDING FFG SHOW MOD INDICES THRU THIS REGION TNGT.

ECKERT
$$