WORLD CBS-DPFS/SWFDP-RTIT/Doc. 5.3(1)
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Agenda item : 5.3 SEVERE WEATHER FORECASTING DEMONSTRATION PROJECT (SWFDP) - SOUTHERN AFRICA, MEETING OF THE REGIONAL TECHNICAL IMPLEMENTATION TEAM
PRETORIA – SOUTH AFRICA – 24-27 FEB. 2009
NATIONAL METEOROLOGICAL CENTRE - ZIMBABWE REPORT ON THE COUNTRY STATUS
OF THE SWFDP – SOUTHERN AFRICA IMPLEMENTATION PHASE TO THE MEETING OF THE
(Submitted by NMC ZIMBABWE)
Summary and purpose of document
This document seeks to give a summary of the status of the
Severe Weather Forecasting Demonstration Project – Implementation
Phase within the Zimbabwe Meteorological Services Department. In
brief, the implementation phase of the project which started in
November 2008 has commenced as planned although a few
challenges continue to be faced. Spreading the project countrywide is
now a key element in expanding net benefits of severe weather
The meeting is invited to analyze the document and give its recommendations and contributions.
CURRENT FORECASTING PROCESS
The current forecasting process within the Zimbabwe Meteorological Services Department starts with an analysis of the past weather. This is then followed by a look at the present weather or initial state by analyzing the surface and upper air observations as well as MSG satellite imagery. NWP products and guidance from the regional centers is taken into account and a prognosis is made initially concentrating on the first 3 days and then for the extended forecast period of up to 10 days.
The various charts and NWP products used by the duty forecaster are discussed at a weather briefing that takes place at 11:30am on a daily basis in the Central Forecast Office involving forecasters and meteorologists from within the department. Discussion and sometimes debate, is normally kick started by a MS PowerPoint presentation by the duty forecaster.
Out of these discussions, a forecast sometimes with an advisory or warning, is issued. All the material used including the satellite pictures, NWP products, guidance, reports, warnings and advisories to the press are then archived for verification and future reference.
An integrated warning criteria is still in the pipeline pending the enactment of the Emergency Preparedness and Disaster Management Bill. The new act is expected to repeal the current Civil Protection Act which is rather limited in scope and does not provide for the use of a uniform warning criteria by the Civil Protection Unit. The current warnings that are being issued in relation to severe weather in Zimbabwe are usually as follows: i) heavy rain and ii) heavy rain and flooding.
DISSEMINATION TO MEDIA AND DISASTER MANAGEMENT AND CIVIL PROTECTION
Dissemination to the media is via 2 ways. Direct through weather reports and press statements from the weather service and indirectly through joint press statements with Civil Protection Unit (CPU) and the Zimbabwe National Water Authority (ZINWA - hydrologists).
Dissemination to the DMCPA of severe weather forecasts is direct from the National Meteorological Centre with contact persons having been identified in both institutions. The contact persons of the DMCPA are those individuals who attended the Maputo (2007) and the Pretoria (2008) meetings which included members from the DMCPA. Contact persons in the NMC are any member the Severe Weather Forecasting Team that has been created within the NMC and consists of forecasters that have received some form of severe weather forecasting training either through the SWFDP or another training programme.
CURRENT RELATIONSHIPS WITH THE MEDIA AND DISASTER MANAGEMENT
The NMC Zimbabwe still maintains excellent relationships with media houses in disseminating severe weather warnings, weather reports and giving feedback on how our severe weather forecasts are performing. NMC articles made headlines in the national newspaper (The Herald) a
total of six times and on current affairs programmes and main news bulletins on television (ZBC TV) at least eight times on matters related to heavy rain, flooding and the seasonal forecast since mid-December 2008 when the main rains commenced countrywide. Numerous reports were also aired via the four national radio stations. From the beginning of 2009, two heavy rain and flood warnings th were issued by the NMC in conjunction with the DMCPA and Water Management Authority (8and th14 of January) and they received tremendous coverage in the print and electronic media.
FEEDBACK AND VERIFICATION OF FORECASTS AND WARNINGS
Feedback As highlighted in the diagram on page 3 feedback on the NMCs forecasts and warnings is received from various sources which include the affected communities, the media, the DMCPA and Water Management Authorities.
Verification Severe weather forecast verification has over the years been of interest to the NMC but has usually been limited in scope. The daily chart discussions start with a look at the 24 hour past weather and a verification of the weather forecast issued two days earlier. Individual forecasters have also carried out verification of particular parameters for selected stations as well as verification of individual NWP products issued by the various centers.
PROGRESS SINCE PRETORIA 2008
Notable progress has been made within the Central Forecasting Office of the NMC since the Pretoria 2008 SWFDP training exercise. The training exercise coincided with the purchase of a new MSG platform by the NMC which provides the full range of MSG imagery and derived products. The new system was installed and started running in early December 2008 and has enhanced our diagnosis of recent past weather and the initial state which are vital elements in the forecasting process. The system has also added more NWP products in addition to those provided via the SWFDP.
The period since November 2008 has seen greater use of the hydroestimator in verifying rainfall forecasts especially the 24 hour panel. Although, the estimator clearly tends to overestimate, it is none-the-less proving to be a good diagnostic tool. Changes in the rainfall intervals on the scale of the hydroestimator product and the none availability of the product on a few occasions are making comparisons from day to day difficult.
In line with expectations of the implementation phase of the SWFDP, a better structured and rd of December 2008. This documented heavy rainfall forecast verification exercise begun on the 23
ongoing exercise seeks to verify the heavy rain predictions by the NMCs Central Forecast Office together with those of the RSMC guidance product against gauge data and hydroestimator.
There are now plans to spread Severe Weather training to other forecasters at airports across the country and those in the agricultural meteorology and rainfall sections on what severe weather entails. Particular attention is being given to forecasters in the aviation sector with training workshops being planned during the course of 2009 for forecasters at our three international airports (Harare, Bulawayo and Victoria Falls). This will ensure that severe weather is included and pointed out explicitly in both our public weather forecasts as well as specialized forecasts for our wide range of clientele.
The diagram on page 3 summarizes the flow of severe weather information from NMC
Zimbabwe to intended users and the various feedback paths. Please note that this excludes the NMCs own internal feedback mechanisms like satellite estimates and synoptic, climate and volunteer station reports.
(i) WMO, for deciding to continue with this project and for extending to other SADC
(ii) SAWS for continuing to host the project
(iii) Global centres for availing their models to the region
Daily weather Met service specialized MET SERVICE
reports/bulletins, newsletters: 10 day Agromet MEDIA
advisories bulletin & weekly Rainfall bulletin
Severe weather prediction ZINWA
(hydrology) CIVIL PROTECTION
management) Flood prediction. Yes/No?
Joint statements on the Mobilize various arms of impending severe Gvt/civil society etc. weather, flooding and
MEDIA Informing CPU local
structures in areas to
affected, local leadership
COMMUNITIES ESPECIALLY THOSE EXPECTED TO BE AT RISK
Severe weather information flow diagram. Red arrows represent the flow of information from the Meteorological Service to various
stakeholders while the blue arrows represent the feedback loop.
This report was prepared by the Zimbabwe Meteorological Services Department Severe Weather Forecasting Team
Tirivanhu Muhwati – Head of Rainfall and Hydrometeorology section, Tichaona Zinyemba – Head of the Central Forecasting Office, Jonathan Chifuna – public weather forecaster, Reynold Ndoro – public weather forecaster and Patrick Mukunguta – aviation weather forecaster.