Broad-scale measurements of rainfall using technology such as Doppler weather RADAR are a great supplement to gauge-based precipitation monitoring but there is not always a RADAR where you need it when you need it. In contrast, wherever there are people with cellphones, i.e. nearly everywhere, there will be Commercial Microwave Links (CML) that are sensitive to precipitation. While far from ideal as a rain sensor the ubiquity of these installations is a compelling argument. This investigation looks at exploiting this space-time resolution by joint use with rain gauges.