Numerical Guidance to Support the Weather Ready Nation

Impact-based decision support services (IDSS) depend critically on real-time analyses of the physical environment (to enhance forecaster awareness) and numerical guidance products to inform users of future societally-impacting events. A Rapidly Updating Analysis (RUA) of the physical environment (atmosphere, land, hydrology, ocean and cryosphere), is proposed as a first step to increase forecaster situational awareness. The RUA will fuse information from multiple observing sources with a background state having uniform coverage over forecaster service domains. The RUA will be updated sub-hourly over areas where new information is received and products impacted by this new information will also be updated. The RUA is envisioned to cover the current North American domain, from the surface to the lower stratosphere, at a resolution equal to or less than 5 km. Some products, such as those from NEXRAD and other radars, may be at 1 km resolution with 5 minute refresh periods over CONUS. RUA products and high resolution numerical guidance for Alaska, Hawaii and Puerto-Rico/Hispaniola are also planned.

Numerical guidance is essential to provide detailed and accurate information on the future evolution of weather events and enhance user preparation. In the next decade, numerical guidance will evolve to higher resolution systems with increased accuracy measurable in terms of Probability of Detection (POD) and False-Alarm Rate (FAR). While current observing systems may well be enhanced and new ones may evolve, a major key to success is the ability of data assimilation algorithms to extract information from existing observations in order to increase forecast accuracy.

This presentation will describe the evolution of real-time analyses and forecasts over the next decade. Outlooks for observing and computing resources will be given and the anticipated support to various mission applications such as aviation and hydrological services will be discussed.