TITAN Workshop on Techniques for Convective Storm Nowcasting
Mike Dixon Earth Observing Laboratory (EOL) Research Applications Laboratory (RAL) National Center for Atmospheric Research (NCAR) NCAR, Boulder, Colorado Friday 20 May 2011 The TITAN algorithm is designed to identify and track convective storms it is an extrapolation algorithm Detection is performed using a series of reflectivity thresholds and other parameters Tracking allows storm motion estimation and hence forecasting Typical TITAN workstation screen A brief history of TITAN
Started small . Grew iteratively over time TITAN development begins at NCAR 1990 - 1992
Development began on porting the original FORTRAN software to C/C++, running under UNIX. Cartesian conversion from polar coordinates was implemented. Storm identification and tracking was improved. Rview/TimeHist display was developed. TITAN was tested on the prototype NEXRAD radar in Denver, Colorado. TITAN development at NCAR 1992 - 1994
Extrapolation forecasting was added to the TITAN tracking module. The Federal Aviation Administration (FAA) became interested in the forecasting potential of TITAN TITAN was configured to run on the Kavouras 2-D radar mosaic over the continental US. This ran operationally for an FAA demonstration in 1993. TITAN rap operationally in RAPS93 field experiment in the Colorado Front Range. TITAN/auto-nowcaster development at NCAR 1994 - 1996
In 1994, work began on the NCAR Auto-nowcaster, of which TITAN is an important component. NCAR scientists worked with TITAN and the auto-nowcaster, validating the tracking and the forecasts. TITAN and the auto-nowcaster ran during the RAPS95 field experiment in the Colorado Front Range. CIDD was used as the general-purpose display for TITAN for the first time. Weather modification experiment Coahuila, Mexico 1996 - 1998
A randomized seeding experiment for rain enhancement was carried out in Coahuila, Mexico. TITAN was ported to an early version of LINUX and run operationally on a PC for the first time. TITAN was used as the operational software for controlling the seeding, gathering aircraft track data. The seeding evaluation (re-randomization) components of the software were added. Advanced Operational Aviation Weather System (AOAWS) Taiwan
The AOAWS is built on the TITAN software system Many enhancements were made to the TITAN software system for this project National Convective Weather Forecast system (NCWF)
NCWF uses a blend of Titan storm identification and tracking and other techniques to produce a forecast Example ofusing TITAN for nowcastingRecent Tornado Outbreak in Eastern USA Tornado outbreak North Carolina Low-angle reflectivity Velocity field showing rotations Titan gives different views into storm and track properties Consider a single storm, represented as a polygon Use ellipses for clarity and show the recent past Now consider the forecast based on extrapolation And compare the forecast to what actually happened Time history allows analysis of the storm properties
Time-height profile of rotation Second example of a good forecast Another example of a good forecast TITAN used for Nowcasting in Brazil Severe weather outbreak State of So Paulo
The severe events on October, 17th and on March 29th developed and evolved in an environment under the influence of a baroclinic system reaching the State of So Paulo They produced a squall line, with intense cells forming ahead of the frontal disturbance with an extended trailing stratiform area. Warning Bulletin Issued on 29 March 2006 Automated Weather Alert System
AUTOMATIC ALERT webserver client MAPSERVER MANUAL ALERT XML browser Apache ExtJS XML IPMet PostGIS Storms browser XML Weather Data TITAN Active Layers: CAPPI Topography City Borders Rivers Roads
TITAN Storms: Current and Forecast IPMet Twitter showing severe weather events in real-time
Drawing tool is available for users areadefinition 25 May 2004: TORNADOES & SUPERCELLS
C1: Weak Echo Region and radial velocities inside the core indicating a strong updraft and cyclonic rotational forces between 4 and 9km height (Vr 35 m.s-1); T1: spawning a tornado (F2-F3), hook echo up to 6km and radial velocities ranging from 28 to +9 m.s-1 forming a couplet (shear maximum of 5,2x10-3s-1). Palmital 25/05/2004 ~ 14:00h TITAN in Australia Sydney hailstorm 14 April 1999
Total cost of damage $2b Hail up to 9 cm observed Observed by two radars Sydney (10cm) Kurnell (5cm Doppler) Lifetime 5.5 hr 49 dBZ storm track TITAN was valuable tool for objective analysis of this storm event. NSW RFC operational criteria for severe storm is when 49 dBZ reflectivity exceeds 8 km in ht. Figure shows the track of the 49dBZ contour and times when 49 dBZ exceeded 8 km are indicated. Lifetime of storm 5.5 hr. Average movement of storm towards 025 deg at 9 m/s. Thunderstorm Interactive Forecast System (TIFS)
Graphical interactive interface that streamlines generation of severe storm warnings Displays TITAN output from Nowcast Applications Servers as guidance Thunderstorm impacts on airport operations
Lightning ramp closure Aircraft docking Passenger loading / unloading Refuelling / catering / cleaning Flight delays / cancellations Air traffic delays / diversions Flow-on impacts can be extensive Manual alerts ineffective Automated Thunderstorm Alert Service information flow
Graphic products (1 min) Text alert Electric / magnetic / optical sensors TITAN in South Africa Combined lightning and radar product
No radar coverage THANK YOU