EXCESSIVE RAINFALL DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 212 AM EDT FRI JUN 11 2010 ...VALID 06Z FRI JUN 11 2010 - 12Z SAT JUN 12 2010... ...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL... SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM 10 SW HUF 20 ENE BMG 35 S BAK 15 E OWB 35 NW HOP 15 SSW HKA 25 E SGT 30 W LLQ 25 SSE TXK 30 NE OSA 20 NNE LBR 25 SSE RKR 20 W RUE BPK 15 W FAM 20 WNW ENL 10 SW HUF. SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM 50 ENE AIA 35 NNW TIF 25 ENE ANW 20 S MHE PQN 20 NNW MWM 20 NNE ULM ANE 10 S CDD 10 WSW IWD 20 N LNL 10 SE SAW 15 WSW PZQ 15 SE ACB 10 ENE GRB 20 S CMY OLZ 25 SSW DSM 10 NE STJ LWC 10 E EMP 25 W EMP 40 NNE EWK 20 W MHK 20 E CNK 15 NNW CNK 40 WSW HJH 20 SSE HDE 25 ESE MCK 35 S IML 40 NW GLD 35 NE LIC 10 NE DEN 10 S PUM 30 ENE ARL 20 W SIB 35 ENE SIB 20 SW CDR 50 ENE AIA. WEAK UPPER LVL DISTURBANCE..ACTING MORE LIKE A FORMER TROPICAL LOW..CONTINUES TO BE THE FOCUS FOR SGFNT CNVCTV RAINS..AND SHOULD REMAIN SO THRU THE PD. A STG AND MOIST SSWLY LLVL MSTR FETCH CONTINUES TO IMPINGE ON THE SLOWLY LIFTING OUT SYSTEM UNDER BROADLY DIV FLOW ALOFT ENHANCING SHWR DVLPMNT. WHILE THE GRADUAL ACCELERATION OF THE SYSTEM WILL EVENTUALLY LIMIT EXCESSIVE RNFL TOTALS..CANNOT RULE OUT THE POSSIBILITY THAT CELL INTERACTION AND SGFNT PW AVBLTY COULD RESULT IN SPOTTY EXCESSIVE RNFL TOTALS ALONG ITS TRACK. COULD SEE QUICK 2.00 INCH RNFL AMTS WITH ISOLD TOTALS IN THE 3.00 TO 5.00 INCH RANGE BEING POSSIBLE. WHILE ADMITTING THE LARGE OUTLOOKED AREA FM THE GREAT LAKES WSWWD TO E SLOPES OF THE CNTRL ROCKIES IS LIKELY OVERDONE..IT IS DIFFICULT TO PRECLUDE EXCESSIVE RNFL AMTS WITHIN THIS AREA GIVEN MODEL QPF GUIDANCE BEING ALL OVER THE PLACE. BASICALLY...SHRTWV ENERGY BEING EJECTED ACROSS THIS REGION FM THE WRN U.S. UPPER TROF WILL CONTINUE TO FIRE SHWRS WITHIN A BROAD BAROCLINIC ZONE LYING ACROSS THE AREA. IN ADDITION..PIECES OF SHRTWV ENERGY LIFTING NWD THRU THE PLAINS FM THE SUBTROPICAL STEAM WILL COMPLICATE MATTERS AND BELIEVE MODEL QPF GUIDANCE IS IGNORING THIS POSSIBILITY. IN ANY CASE...PWS IN PLACE AND A CONTG NWD MSTR FLUX TO ABET MSTR AVBLTY SHOULD SUPPORT HVY RNFL TOTALS WITH SFC WVS OVER THE UPPER MS VLY AND INVOF THE CNTRL HI PLAINS BY MID PD ENHANCING THE LLVL INFLOW IN THOSE AREAS. RT ENTRANCE REGION DYNAMICS WILL ENHANCE THE SYNOPTIC SCALE FORCING ACROSS THE UPPER MS VLY/GREAT LADES REGION SUPPORTING WHAT SHOULD BE A STRONG ISENTROPIC LIFT EVENT THERE. PLEASE SEE THE LATEST QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION TO BE ISSUED SHORTLY FOR A MORE DETAILED DISCUSSION OF THE SYNOPTIC SCALE SITUATION. KORTY $$