Rapid Refresh (RAP) and High-Resolution Rapid Refresh (HRRR) Forum

PW QC in RUC13

Posted By: Stan Benjamin
Date: 22-October-04 0425Z

An improved QC technique for precipitable water obs has been designed for the 13km RUC, to be implemented in 2005. The improved PW QC technique is currently running in the development FSL RUC runs at 20km and 13km. The PW QC technique compares GPS prec water and raob PW values, and has been found very helpful to catching raob moisture problems, such as the one that showed up in the Lake Charles raob from Wednesday evening (see NWS message below). The new PW QC in the RUC13 successfully flagged this ob, which was a problem in the operational RUC20 and all other NCEP models: AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FORT WORTH TX 420 AM CDT THU OCT 21 2004 .DISCUSSION... ALL 0Z MODELS SEEMED TO HAVE INGESTED BOGUS DATA FROM THE 0Z LCH SOUNDING...WHICH SHOWED PRECIPITABLE WATER AT 2.3 INCHES...LIKELY AN INCH TOO HIGH. SUBSEQUENTLY THIS HAS IMPLICATIONS ON THE FORECAST THE MODELS GENERATE WITH GFS/ETA/NGM/ RUC ALL DEVELOPING PRECIP OVER THE AREA TODAY WITH UNREALISTIC HIGH CAPES/PWS. WILL DISCOUNT THESE PROGS AND CONTINUE A DRY FORECAST...AND HOPE THAT THIS BAD DATA DOES NOT CONTAMINATE PROGS PAST 24 HOURS...

Rapid Refresh (RAP) and High-Resolution Rapid Refresh (HRRR) Forum is maintained by RR/RAP Forum Administrators with WebBBS 5.12.