Climate Perspectives: A Web-based Tool for Assessing the Unusualness of Recent and Forecasted Temperature and Precipitation patterns

Society is becoming more sensitive to the occurrence of weather extremes, especially as climate change is increasing the frequency of various types of extreme events. Consequently, the public is increasingly asking meteorologists to provide a climatological context for recent or forecasted weather events; they want to know, for example, how unusual or rare an event is or how it ranks with similar events in the past. The NOAA Southeast Regional Climate Center (SERCC), in response to this need, has developed a web-based tool, Climate Perspectives (CLIMPER), that allows users to readily identify the unusualness of recent or anticipated temperature and precipitation patterns. CLIMPER (https://sercc.com/climate-perspectives/) ingests weather data from the Regional Climate Center’s Applied Climate Information System (ACIS) as well as the NWS National Digital Forecast Database (NDFD) to generate a rich mix of climatological information across a range of time periods spanning three days into the future to two years in the past. These climate perspectives provide a synopsis of temperature and precipitation patterns in terms of how they depart from values observed in the past. The daily updated climatological information allows the user to readily assess the extremeness of an ongoing weather event or regime (e.g. exceptionally hot, cold, or wet conditions) over the prior days, weeks, or months by seeing how it compares with historical record during the same calendar period. Since weather departures are identified over time periods that can cross months, the information is not bound by the artificial boundaries imposed by calendar months, like traditional climatologies. The user can select from thousands of stations, including ASOS stations and Cooperative Observer stations across the continental United States, Alaska, and Hawaii, as well as Puerto Rico and the Virgin Islands. They can view climate perspectives for minimum, maximum, and mean temperature as well as precipitation. In addition, they can see what city across the United States has the most similar temperature based on their climatological normals. For example, an observed daily maximum and minimum temperature of 22°F and 9°F, respectively, on a given day in January might be identified most similar to the temperatures typically experienced in Minneapolis, MN. A user can also identify events or periods in the past record in which similar weather conditions were observed. The latest version of CLIMPER enables the user to readily export regional or national outputs to a CSV file to make maps for media stories.