EXCESSIVE RAINFALL DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 259 PM EDT THU JUN 10 2010 ...VALID 18Z THU JUN 10 2010 - 00Z 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 25 ESE EAU 15 SSW EAU 15 SSW MKT 15 N SPW 25 NW BVN 30 W LBF OGA 35 NNW OGA 45 WNW TIF 15 SSE 9V9 15 SW VVV 10 SW SAZ 15 NNW AIT 20 NNW DLH 40 SSE GNA 20 E CMX 40 NE SAW 25 WNW P75 25 WSW ESC 10 W RRL 25 ESE EAU. SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM 35 NNW GLH 15 N BQP 30 W BQP 40 E BAD 15 SSE BAD 30 SSE GGG 15 SE JSO PSN 20 WNW PSN 20 ENE CRS 20 ENE LNC 20 SE TRL 10 SW SLR 30 WNW DEQ 30 SE FSM 25 N RUE 40 W POF 30 ESE FAM 10 N MWA 10 N M30 25 NNE DYR 15 WSW UTA 35 NNW GLH. MODERATE RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM 3T1 20 ESE LBR 20 SSE DEQ 35 WSW M89 10 SW M89 25 ESE M89 25 SW PBF 20 WNW LLQ 25 SW LLQ 25 ESE ELD 25 SSW ELD 25 NE BAD 15 WNW DTN 20 ENE GGG 20 SW GGG 15 SW TYR 20 WSW TYR 20 WNW TYR 10 SW 3T1 3T1. TOTAL RAINFALL AMOUNTS OF FIVE INCHES WILL BE POSSIBLE TO THE RIGHT OF A LINE FROM 40 SSE SGT 20 NE LLQ 15 S LLQ 30 WNW BQP 30 SSW ELD BAD 15 WSW SHV 20 SE GGG 20 ENE JSO 15 WNW JSO 30 NNW PSN 25 ESE TRL 10 SE SLR 10 SE DEQ 15 NW HOT 25 WNW LZK 15 NNE SRC 10 S M19 35 ENE SGT 40 SSE SGT. NERN TX...FAR NWRN LA...SCNTRL AR... THE PREVIOUS EXCESSIVE RAINFALL POTENTIAL OUTLOOK WAS ADJUSTED FOR CURRENT RADAR TRENDS AND LATEST MODEL GUIDANCE. WITH THE MODEL IN GENERAL AGRMNT ON A MORE PROGRESSIVE NEWD PUSH TO THE PERSISTENT NERN TX MID LEVEL VORT...THE THREAT AREA WAS EXTENDED NEWD INTO NERN AR..FAR SERN MO AND FAR SRN IL TO REFLECT THIS PROGRESSION. THE HIGH PROBABILITY AREA WAS DROPPED AS THE SYSTEM WL BE MOVG OVR REGIONS WHERE FFG VALUES ARE HIGHER. OTHERWISE...THINKING FROM THE PREV FCST REMAINS THE SAME WITH CONVECTION LIKELY TO REMAIN WELL DEFINED AND VERY SLOW MOVG INVOF THIS SLOW MOVG MID LEVEL VORT. THE NAM IS ON THE SLOW END WITH THE NEWD PUSH OF THIS SYSTEM AND THE GFS ON THE FAST END OF THE MODEL SOLN ENVELOP. THE NAM HAS NOT PERFORMED WELL WITH THIS SYSTEM OVR THE PAST FEW DAYS..WITH THE EC AND GFS SHOWING BETTER SKILL. AT THE MOMENT...WE SUPPORTED THE ECMWF NEWD SPEED AS A COMPROMISE. THIS SYSTEM WL REMAIN EMBEDDED IN AN AXIS OF ABOVE AVERAGE PW VALUES..2-2.25"+. THIS WL CONT TO SUPPORT ACTIVE CONVECTION INVOF THE CNTR...WITH ACTIVITY FARTHER AWAY DURG THE DAY LIGHT HOURS AND LIKELY CONTRACTING CLOSER TO THE CNTR AT NIGHT. THE HIGH PWS AND SLOW MOVEMENT...ESPECIALLY EARLY THIS PERIOD...WL SUPPORT THE POTENTIAL FOR ADDITIONAL VERY HEAVY RAINFALL AS PCPN AREA MAY TRAIN OR REMAIN NEARLY STNRY INVOF THE MID LEVEL CNTR. SHRT TERM PCPN AMTS OF 2"+ POSSIBLE IN AREAS OF TRAINING OR STNRY CONVECTION. WITH THE TREND TOWARD PROGRESSION THIS PERIOD...THE TOTAL PCPN AMTS WL LIKELY NOT BE AS GREAT AS IN PREV DAYS...BUT THE POTENTIAL STILL EXISTS FOR TOTAL AMOUNTS IN EXCESS OF 5". THIS WL BE ESPECIALLY SO EARLY IN THE PERIOD WHEN THE SYSTEM WL BE STILL MOVG SLOW AND CONVECTION MAY ENHANCE NEAR THE CNTR IN THE EARLY MORNING HOURS. CNTRL-NRN PLAINS INTO THE UPR MS VALLEY...UPR LAKES REGION... LATEST SATL AND RADAR IMAGERY CONT TO SHOW DISSIPATION TO THE MCC MOVG INTO THE MID WEST WITH WARMING CLOUD TOPS AND DECREASING RADAR RETURNS SIGNALING THE CONTINUED DECREASE IN THE HEAVY PCPN THREAT FROM THIS MCC. IN THE WAKE OF THIS WEAKENING MCC...THE LOW LEVEL FLOW WL STRENGTHEN TONIGHT ACRS THE CNTRL TO NRN PLAINS HELPING TO SUPPORT ADDITIONAL ORGANIZED CONVECTION AHEAD OF THE SFC WAVE FCST TO PUSH ENEWD FROM ERN PORTIONS OF THE NRN-CNTRL PLAINS...INTO THE UPR MS VALLEY AND UPR LAKES REGION THIS PERIOD. ALL GUIDANCE IS SIGNALING POTENTIAL FOR HEAVY PCPN AMTS ACRS THIS REGION...ALTHOUGH THERE IS STILL A LARGE DEGREE OF SPREAD WITH THE LAT OF THE MAX AXIS. THE 1200 UTC ECMWF HAS TRENDED SLIGHTLY TO THE SOUTH FROM ITS 0000 UTC RUN. WE LEANED. SHRT TERM PCPN AMTS OF 1-2" AND ISOLATED TOTALS OF 2-4" POSSIBLE THIS PERIOD ACRS THESE REGIONS. ORAVEC $$