Precipitation Potential Placement

Precipitation Potential Placement is a derived parameter combining precipitable water and low-level mean RH to help better place where rainfall will occur. Research has been published in the National Weather Association Digest in 2003 and stems from research and operational use of this product originally developed at NESDIS and Rod Scofield for satellite rainfall estimates dating back to 1981.

Rainfall is usually maximized where the best low level convergence and instability overlay with the highest values for this parameter.

The risk for heavy rainfall increases as values go up. Additionally, thresholds for precipitation also change based on temperatures. Onset of rainfall ranges from around 0.3 inches with temperatures below 30 to 1.0 inches above 80. Values above 1.0-1.4 inches with temperatures below 60 usually increase the risk for heavy rainfall while values above 1.6-2.0 inches increase the risk for heavy rainfall events with temperatures above 60.

For more information, see: