september 2005wsn05, toulouse, france applications of the mcgill algorithm for precipitation...

September 2005September 2005 WSN05, Toulouse, France WSN05, Toulouse, France

Applications of the McGill Algorithm for Precipitation Nowcasing Using Semi-

Lagrangian Extrapolation (MAPLE) within the ARPAV HydoMet Decision Support

System

Bill Conway1, Dr Gabriele Formentini2, Chip Barrere1, Dr Luciano Lago2

1Weather Decision Technologies, Norman, Oklahoma, USA

2Environmental Protection and Prevention Agency Veneto Region, Centro Meteorological, Teolo, Italy


Teolo radar viewed from weather station


View of Teolo towards Venice from weather station


Presentation BackgroundPresentation Background WDT has worked with ARPAV in Italy to provide a HydroMet

Decision Support System (HDSS)

HDSS contains technologies developed by WDT, the National Severe Storms Laboratory, McGill University of Montreal, Canada, and the Oklahoma Climate Survey

HDSS integrates numerous data sources and contains algorithms that provide the following functionality:

Storm centroid tracking, analysis, and prediction Storm area tracking and prediction (MAPLE) Rainfall prediction using MAPLE Hail detection and prediction Circulation prediction and detection Quantitative Precipitation Estimation Using Multiple Sensors Web based display – WxScope three dimensional workstation display – 3D Sigma

This paper concentrates on application of the MAPLE algorithm and its applications with the ARPAV HDSS to reflectivity forecasting and rainfall prediction


HDSS Web Page ExampleHDSS Web Page Example


MAPLE - BrieflyMAPLE - Briefly Developed at McGill University, Montreal, Canada by Zawadski and

Germann over a period of several years

Provides forecasts of reflectivity out to 8 hours depending on scale predictablity

Uses prior image history to forecast reflectivity out to 8 hrs in advance using stream function analysis

Determines the changing scale of predictability using past images compared to current image though wavelet analysis

Filters non-predictable scales from the T=0 analysis

Deduces stream functions for predictable scales and uses those stream functions to forecast radar reflectivity location and intensity

Current research includes integration of numerical model data for applications towards storm growth and decay

WDT has developed software to run MAPLE in real-time for commercial applications and also to provide radar based QPF


Example Vector Derivation


1.5h

>8h

5.5h

C a n a d a

Gulf of Mexico

Scale predictability determinedby comparison of previous forecastswith current images.

Scales are removed in the forecastafter exceeding their derived“predictability” flag

Example of Scale Predicability


Example 4 hr Precip Type Forecast 4 hr Precip Type Forecast


Hybrid ScanningHybrid Scanning

Grey – data from 1st elevationYellow – data from 2nd elevationOrange – data from 3rd elevation


Hybrid Scan Example


MAPLE Applications to QPFMAPLE Applications to QPF Uses output from QPE-SUMS as “T0” input for Uses output from QPE-SUMS as “T0” input for

MAPLEMAPLE

Applies a Z-R or Z-S relationship to each 5 min Applies a Z-R or Z-S relationship to each 5 min MAPLE time step based on surface MAPLE time step based on surface temperature and whether stratiform or temperature and whether stratiform or convectiveconvective

Will apply a bias correction at each time step Will apply a bias correction at each time step based on QPESUMS radar to gauge correction*based on QPESUMS radar to gauge correction*

Accumulates total rainfall forecasts at each Accumulates total rainfall forecasts at each grid point across the MAPLE domaingrid point across the MAPLE domain


Objective Analysis of Rain Gauge Data


Example of variable Z-R/Z-S Relationships


1 Hr MAPLE Hybrid Forecast


MAPLE 2 hr Accumulation


Future WorkFuture Work McGill continuing to work on model integration and storm growth/decay McGill continuing to work on model integration and storm growth/decay

for MAPLE improvementsfor MAPLE improvements

Correct Italian data for beam blockageCorrect Italian data for beam blockage

Integrate further radars from Italy network as they become availableIntegrate further radars from Italy network as they become available

Develop software for real-time statistical analysis of MAPLE performanceDevelop software for real-time statistical analysis of MAPLE performance

Optimize the Z-R and Z-S relationships used in the northern Italy regionOptimize the Z-R and Z-S relationships used in the northern Italy region

Use basin delineation and flash flood guidance with MAPLE QPF results to Use basin delineation and flash flood guidance with MAPLE QPF results to provide a Flash Flood Prediction Algorithmprovide a Flash Flood Prediction Algorithm

Merci! Grazie! Thanks! Ciao!Merci! Grazie! Thanks! Ciao!

september 2005wsn05, toulouse, france applications of the mcgill algorithm for precipitation...

Documents

france maple

france applications

rainfall prediction

qpf slide

france teolo radar

france view of teolo

rd elevation slide

france hdss web page