UNDERSTANDING AND MODELING THE BACKGROUND SOLAR WIND IS KEY FOR MODELING THE PROPAGATION OF CORONAL MASS EJECTIONS. TO MODEL THE SOLAR WIND IT IS COMMON TO FIRST MODEL THE CORONAL MAGNETIC FIELD USING POTENTIAL FIELD SOURCE SURFACE (PFSS) TYPE MODELS DRIVEN BY OBSERVATIONS OF THE MAGNETIC FIELD AT THE SOLAR SURFACE. FROM THE OUTER BOUNDARY OF THE PFSS BASED MODEL ASSUMING RADIAL SOLAR WIND STREAMS AND A SIMPLE MODEL FOR THEIR INTERACTIONS LEADS TO PREDICTIONS OF THE SOLAR WIND SPEED IN THE HELIOSPHERE. THIS APPROACH FORMS THE BASIS FOR THE WANG-SHEELEY-ARGE (WSA) MODEL. WITHIN THIS BASIC FRAMEWORK THERE ARE A NUMBER OF CHOICES IN HOW TO IMPLEMENT THE MODELS PARTICULARLY IN HOW TO GENERATE THE RADIAL MAGNETIC FIELD BOUNDARY CONDITION FOR THE WSA MODEL. SINCE ONLY HALF OF THE SURFACE OF THE SUN IS TYPICALLY OBSERVED AT ANY GIVEN TIME ASSUMPTIONS MUST BE MADE ABOUT THE MAGNETIC FIELD ON THE FAR SIDE OF THE SUN. THE AIR FORCE DATA ASSIMILATIVE PHOTOSPHERIC FLUX TRANSPORT (ADAPT) MODEL IS ONE APPROACH FOR ASSIMILATING NEW OBSERVATIONS INTO A FULL-SUN MAGNETIC FIELD MAP. RADIAL MAGNETIC FIELD OBSERVATIONS ARE AVAILABLE BUT ARE TYPICALLY NOISIER THAN LINE OF SIGHT MAGNETIC FIELD OBSERVATIONS PARTICULARLY IN CRITICAL AREAS LIKE THE POLAR REGIONS AND THERE IS PRESENTLY NO OPERATIONAL DATA SOURCE FOR VECTOR MAGNETOGRAMS. SEVERAL WAYS OF ESTIMATING THE RADIAL COMPONENT OF THE FIELD FROM THE LINE OF SIGHT COMPONENT EXIST INCLUDING THE RADIAL FIELD APPROXIMATION AND USING THE RADIAL COMPONENT OF A POTENTIAL MAGNETIC FIELD WHOSE LINE OF SIGHT COMPONENT MATCHES THE OBSERVATIONS. THE PROPOSED INVESTIGATION WILL TEST HOW TO GENERATE THE BEST INSTANTANEOUS RADIAL MAGNETIC FIELD MAP FOR THE VISIBLE HEMISPHERE FROM THE AVAILABLE OBSERVATIONS BY COMBINING DIFFERENT APPROXIMATIONS IN DIFFERENT AREAS OF THE SUN. FOR EXAMPLE WE ANTICIPATE THAT THE RADIAL FIELD APPROXIMATION WILL WORK BEST IN NOISY WEAK FIELD AREAS SUCH AS PLAGE FARTHER FROM DISK CENTER WHILE THE POTENTIAL FIELD APPROXIMATION MAY BE BETTER SUITED TO SUNSPOTS. THE INSTANTANEOUS MAPS WILL BE USED AS INPUT FOR ADAPT WHICH IN TURN WILL BE USED AS INPUT FOR THE WSA MODEL. THE QUALITY OF THE INSTANTANEOUS MAPS WILL BE EVALUATED BY COMPARING WSA PREDICTIONS FOR OPEN FIELD REGIONS TO OBSERVED CORONAL HOLES AND COMPARING PREDICTED WIND PROPERTIES WITH IN-SITU MEASUREMENTS OF THE SOLAR WIND. THE INVESTIGATION WILL USE MAGNETIC FIELD DATA FROM THE HELIOSEISMIC AND MAGNETIC IMAGER (HMI) ON BOARD NASA'S SOLAR DYNAMICS OBSERVATORY (SDO) MISSION. VALIDATION OF THE RESULTS WILL BE BASED ON EUV IMAGES FROM SDO'S ATMOSPHERIC IMAGING ASSEMBLY AND FROM THE SOLAR TERRESTRIAL RELATION OBSERVATORY SPACECRAFT (STEREO) AS WELL AS IN-SITU SOLAR WIND DATA FROM THE ADVANCED COMPOSITION EXPLORER (ACE) AND STEREO. THE CENTRAL OBJECTIVE OF THIS PROPOSAL IS TO DEVELOP AN ALGORITHM TO BEST MELD THE DIFFERENT METHODS FOR ESTIMATING THE RADIAL MAGNETIC FIELD ON THE VISIBLE HEMISPHERE OF THE SUN. ALTHOUGH THE VALIDATION WILL BE PERFORMED USING THE WSA MODEL IMPROVED RADIAL MAGNETIC FIELD MAPS WILL LIKELY BE OF BENEFIT TO ALL SOLAR WIND AND CME PROPAGATION MODELS. THE ADAPT MAPS GENERATED AS PART OF THE INVESTIGATION WILL BE MADE AVAILABLE THROUGH THE NATIONAL SOLAR OBSERVATORY WEBSITE SIMILAR TO HOW THEY ARE PRESENTLY PROVIDED FOR USE WITH WSA OR OTHER SOLAR WIND MODELS RUN AT THE COMMUNITY COORDINATED MODELING CENTER (CCMC). THE CODE FOR PRODUCING THE MAPS INCLUDING THE POTENTIAL FIELD CODE WILL ALSO BE MADE AVAILABLE THROUGH THE NWRA WEBSITE.