CLIQR database development David Roth NOAA Weather Prediction Center (Formerly Hydrometeorological Prediction Center) College Park, MD Last Updated: February 28, 2013
What is CLIQR? • The CLIQR (CLImatology of Quantitative Rainfall for tropical cyclones) graphical user interface (GUI) at WPC matches an ongoing tropical cyclone to one in the past based primarily upon current position, forward motion, and storm size (from the CLIQR database). • Output for ongoing systems is generated using CHGHUR/objective guidance messages from NHC which show the current vital statistics of tropical cyclones and tropical disturbances • Manual input can be used within the GUI • Simplified output online for active systems at: http:www.hpc.ncep.noaa.gov/tropical/rain/web/cliqr.html • Information page for CLIQR: http://www.hpc.ncep.noaa.gov/tropical/rain/web/cliqrhtwebhelp.txt
Value in using analogs Analogs allow a forecaster to compare an ongoing weather event to one from the past Past events can be a useful guage in determining effects from a similar ongoing event, if determined in a realistic manner. This type of forecast philosophy is referred to as pattern recognition. Past events can keep a forecaster from forecasting a scenario which is too extreme
Analog choosing for a TC event Size is important…look at the current rain shield and compare it to storm totals/storms from the past How fast is it moving? Vertical wind shear in current/past events? Look for storms with similar/parallel tracks Is topography/prism data a consideration? Look for nearby fronts/depth of nearby upper troughs for current and possible analogs Not all TC events will have a useful analog
CLIQR database development • For size information, the Colorado State University Extended Best Track Database ROCI and POCI values were used as a starting point (1988-2012 for Atlantic, 2000-2012 for northeast Pacific TCs) • Missing information filled in primarily from surface analyses • Gale- and Hurricane-force wind radii have no utility for TC size for T. D.’s and weak T. S.’s. Missing values for the radii were added to the CLIQR database when found. • Tracks were extended based on surface analyses and other sources, such as NHC information online (i.e. 1974-1987 Annual Data and Verification Tabulation of Atlantic TC publications online and scanned recon data messages) • Significant differences with HURDAT2 communicated with Chris Landsea and the NHC Best Track Committee
Surface Analyses Used • HPC North America (2004-2005) • Miami/NHC surface analyses (1956-2011) • NMC North America (1956-1999) • NMC Northern Hemisphere (1956-1996) • NMC Tropical Strip Chart (1976*) • OPC Atlantic (1999-2003) Maps in yellow were digitized by HPC at the NOAA Central Library and University of Virginia, orange by their respective national centers, blue in .vgf format within nAWIPS
CLIQR web output for active systems • http://www.hpc.ncep.noaa.gov/tropical/rain/web/cliqr.html
POCI in yellow, ROCI in green http://www.hpc.ncep.noaa.gov/research/roth/ebtrk_nhc_final.txt
Track Lengthening The CLIQR database utilizes the full history of past cyclones which became STs and TCs to conform with how and when NHC prepares real-time objective guidance for these systems to aid in WPC rainfall forecasts. This accounts for real-time imprecision concerning when phase or strength change occurs with these cyclones (i.e. tropical to subtropical, extratropical to tropical, tropical depression to tropical storm, etcetera).
Summary and Future Work We developed CLIQR for use by forecasters as a sanity check for model guidance output and as an aid in the creation of tropical cyclone rainfall statements included in NHC advisories. Extension of CLIQR database backward to 1946, to account for the time frame when TCs first started being named by the military in the Atlantic Basin. This will encompass more surface analysis map scanning, which dovetails in with WPC's building digital surface analysis archive. Adding vertical wind shear and NHC five-day (soon to be seven-day) forecasts into CLIQR for improved TC rainfall matches.