Drought is a “creeping hazard” whose onset is difficult to identify. New tools, new indices, and new monitoring systems make the early detection of drought more possible than ever before. Although it is difficult to know whether dry conditions are temporary or the beginning of an extended period, real-time data and display tools allow decision-makers to be aware of the possible onset of drought conditions.

Decisions are being made right now about the direction of future observing systems, particularly with regards to modernizing the National Weather Service Cooperative Observer Network (coop). At the same time, legislation in Congress is pending with regards to drought planning and monitoring. The Drought Preparedness Act of 2003 calls for a national drought monitoring network. The needs of the drought network dovetail nicely with plans for the coop modernization, but the planning for both must be integrated at the earliest stages. The modernized coop network would provide real-time rainfall, temperature, and perhaps other important variables such as humidity, wind speed, solar radiation, and even soil moisture. A dense network of real-time observations would allow monitoring incipient drought conditions on an unprecedented scale.

Oklahoma has had the benefit of a mesoscale real-time network – the Oklahoma Mesonet – for nearly ten years. Daily observations of precipitation have proven critical for early detection of drought. The Oklahoma Climatological Survey developed tools to display real-time rainfall data, contrast it with normal conditions over selected periods, and summarize information in regions such as climate divisions. The summaries provide a tool to official state decision makers on a daily basis. Others, including the authors of the Drought Monitor, refer to the products when making determinations about drought conditions in Oklahoma. In addition, recent enhancements to the suite of products include new indices such as the Standardized Precipitation Index (SPI) and analog years, to put precipitation patterns in a context that decision makers can readily understand.