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ROFFG. Romania Flash Flood Guidance System. The Romania Flash Flood Guidance System is an adaptation of the HRC Flash Flood Guidance System used in various regions of the world.
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ROFFG Romania Flash Flood Guidance System
The Romania Flash Flood Guidance System is an adaptation of the HRC Flash Flood Guidance System used in various regions of the world.
The ROFFG is designed to provide flash flood guidance information on a small basin scale across the entire country of RomaniaThe primary purpose of the ROFFG system is to provide real time informational guidance products pertaining to the imminence of potential small-scale flash flooding
The ROFFG system ingests real-time radar and gauge precipitation data on an hourly basis and other meteorological information (e.g. temperature, snow information during winter months), and produces flash-flood-occurrence diagnostic indices over each of 8851 small basins in Romania (with an average area of approximately 30 square kilometers)
The ROFFG system includes two cooperating servers that work in tandem to provide a full array of ROFFG operational acquisition, processing and dissemination features • ROFFG Computation Server • Collect and process real-time data using various models to produce FFG • ROFFG Dissemination Server • Provide secure WWW access to data products for all participating agencies
Products produced by the ROFFG system include the following • RADAR • MERGED MAP • GMAP (Gauge MAP) • ASM (Average Soil Moisture) • FFG (Flash Flood Guidance) • FFT (Flash Flood Threat)
RADAR • Un-biased corrected rainfall for 1, 3, 6 and 24 hour accumulation (based on radar rainfall estimates from the Romania radar network) – only images
Romania has fully integrated three types of radar equipment into one integrated network (SIMIN). • The SIMIN (National Integrated Meteorological System) and DESWAT (Destructive Waters Abatement and Control of Water Disasters), based on 9 Doppler radars (5 new WSR-98D S-band and 4 Doppler radars in C band -EEC and Gematronik),8 lightning detectors, meteorological and hydrological automatic stations, meteorological and hydrological models, warning dissemination systems. • Doppler radars generate an impressive suite of more than 70 products, including both base and derived products. • Available products for flash flood issues: • Base products: R (reflectivity), V (Velocity), W (spectrum Width); • Elevations:=0.5, 1.5, 2.4, 3.4, etc; • Reflectivity range: 5 to >75 dBZ; • Approx. 6 minutes between scans; • Polar products: 1 degree, 1 km; The Romanian radar network
MERGED MAP • Mean areal precipitation for each basin for 1, 3, 6 and 24 hour accumulations based on bias corrected radar rainfall estimates and/or in-situ gauge estimates - text table and images
GMAP (GAUGE MAP) • Mean areal precipitation for each basin for 1 hour (only) accumulation based on available gauge data - text table and image
ASM (Average Soil Moisture) • Average soil water content for each basin (fraction of saturation for the upper soil layer , nominally 20 cm) - text table and image
FFG (Flash Flood Guidance) • Flash flood guidance for each small basin for 1, 3 and 6 hours - text tables and images
Flash flood guidance is the amount of rainfall for a given duration over a small basin needed to create minor flooding (bankfull) conditions at the outlet of the basin. So, FFG is an index that indicates how much rainfall is needed to cause minimal flooding in a basin. • Bankfull flow is employed as the flow associated with flooding
FFT (Flash Flood Threat) • FFT is the amount of rainfall of a given duration in excess of the corresponding FFG value. • The FFT when used with existing or forecast rainfall is an index that provides an indication of areas where flooding is imminent or occurring and where immediate action is or will be shortly needed - text table and images
The FFG and FFT guidance provided by the ROFFG system is not applicable for urban, household or building basement or other flooding not associated with a streamThe FFG and FFT products are considered inappropriate for dates between November 15th and March 1stDuring the winter, the ROFFG still receives data in order to update the soil moisture.
.The Flash Flood Guidance System is not a predictive system in itself, rather it is a diagnostic system for flash floods that the forecaster can use with forecasts or nowcasts of precipitation to produce forecasts and ultimately warnings for flash floods