An analysis of hydrological models was carried out by the Hydrology Group at the USGS EROS Data Center for areas affected by ex-Cyclone Japhet. This analysis was based on estimated rainfall and a variety of rainfall forecasts. The results of this analysis suggest that the Save and Runde Rivers will continue to rise until Thursday, March 6th. River flows are expected to rise to about flood level in the lower parts of the Save River, near the coast, resulting in minor flooding similar to that observed in November, 2002. Heavy rainfall forecast for the upstream areas of the Changane, a major tributary of the Limpopo River, should result in increasing flows in the Lower Limpopo Valley around Chibuto. However, waters in these areas are not expected to approach flood level, and should help to ease hydrologic drought conditions in that portion of the basin. Coastal basins of Inhambane province should be characterized by localized flooding in low-lying areas through the rest of the week.
Meanwhile, after re-strengthening on the night of 3 March, Japhet is now dissipating. The sequence of images in Figure 2 shows the progression of the ex-tropical cyclone, with the latest image (extreme right) showing significantly less activity than the earlier images. National and regional meteorological agencies, as well as forecast models, are forecasting that moderate to heavy rainfall will continue in some areas.
The significant Weather Developments Bulletin is intended to provide timely highlights of developing weather patterns that might pose a threat to human lives and property. While efforts have been made to ensure accuracy of this report, country specific requirements should be addressed to the National Meteorological Services. The RRSU and FEWSNET produce a Situational Regional Floodwatch during the rainy season.
Acknowledgements: The information in this bulletin is derived from an analysis of issuances by the JTWC, La Reunion Tropical Cyclone Centre, and SADC DMC. An analysis of Meteosat satellite imagery, NOAA satellite-derived rainfall estimates, AFWA rainfall forecast models, USGS/FEWS NET water balance and hydrological streamflow models, ground reports, and any other available information is incorporated to estimate ground impacts. USGS/FEWS NET also provides direct input.
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