May blog 2023

Why Your Local Weather Prediction Could Be Wrong .tahmo May 2023 blog

Have you ever checked the weather forecast, only to find out that it was completely wrong? It can be frustrating, but there are many factors that can influence the accuracy of weather predictions. Let’s take a closer look at why weather predictions aren’t always spot on.

Weather predictions are developed by complex mathematical equations that take into account various variables such as temperature, humidity, wind speed and direction, air pressure, and more. However, even with all this data and sophisticated models, there are still many factors that can influence the accuracy of weather predictions.

One of the most significant factors is the availability of accurate data. Weather predictions depend on the collection of precise and timely data from various sources, such as satellites, weather balloons, ground-based weather stations, and radars. If the data is incomplete, outdated, or inaccurate, the predictions are likely to be less reliable.

Another factor that can affect the accuracy of weather predictions is the complexity of the atmosphere itself. The atmosphere is a chaotic and dynamic system, which means that even small changes in one part of the system can have significant impacts on the weather in another part. This makes it challenging to predict the weather, especially over longer time horizons accurately.

Finally, weather predictions are always subject to a degree of uncertainty. Weather models are based on probabilistic forecasts, which means that they provide a range of possible outcomes rather than a definitive answer. It’s important to keep this in mind when interpreting weather predictions and to understand that unexpected changes in the weather can always occur.

Fortunately, organizations such as TAHMO are working to improve weather prediction accuracy. TAHMO is building a network of high-quality weather stations across Africa that provide reliable real-time data. This data can be utilized to improve weather prediction models and help make weather predictions more accurate.

So, the next time you check the weather forecast and it doesn’t come out as predicted, don’t be too hard on the weatherman. After all, weather predictions are simply predictions and not facts. It’s important to understand the limitations of these predictions and to keep in mind the many factors that can influence their accuracy.

Written by Gilbert Mwangi, Technical Director TAHMO

With climate change increasing its mark on all aspects of the hydrological cycle, societies all over the world living in flood-prone areas are increasingly exposed to flood hazards. In many parts of the world,
especially in less developed areas, societies lack knowledge and data to predict future flood events.

By predicting a future flood event, an organization creates a time frame to implement a mitigating action that reduces the financial damage inflicted. In recent years, the development of new measuring techniques has significantly lowered the cost of collecting data and information on different aspects of the hydrological cycle.

These developments enable organizations in regions restrained of knowledge and data to establish methods to analyze aspects of the hydrological cycle, thereby predicting the probability of a flood hazard several hours or days in advance. This thesis explores various possibilities for designing and implementing an Early Warning System (EWS) for the Bus Rapid Transport System (BRT) in Dar es Salaam.

The EWS design is based on the forecasting requirements, investigated with the BRT-system. Several operational forecasting methods are available. The EWS designed in this thesis makes use of rainfall data obtained from rainfall stations located in the Dar es Salaam region, installed and managed by the Trans-African Hydro-Meteorological Observatory (TAHMO).MoreFinal_Thesis_Markus_Pleij_4238001

My name is Honore, and I am a Field Engineer at TAHMO here in Rwanda. My main work is to maintain the network of TAHMO weather stations and act as a representative of TAHMO here in Rwanda.

We have 16 Automatic Weather stations which are distributed in 4 Provinces. Most stations are in Kigali municipal and in the Northern Province.

I joined TAHMO in 2018. My initial goal then was to restore the transmission capacity of Rwandan Stations which had been offline for a while.

The culture at TAHMO has a way of elevating my execution capabilities; it emphasizes staff making decisions and following up with them. The culture also emphasizes planning and innovation. We also have a great support team among ourselves and the management.

Since March 2020 when COVID-19 hit Rwanda (and the world), I had to change a few things. It was difficult to work from home and hope to maintain a high rate of productivity.  Now we use techniques like TeamViewer to maintain stations remotely. I also keep close contacts with the hosts of the weather stations who helps us troubleshoot minor issues.

I was the only TAHMO field engineer when I started. In 2020, I trained 2 volunteer assistant technicians; Jean and Elie. They have been working in northern and southern provinces. I am happy they have quickly adapted to TAHMO culture and are very helpful.

A School-2-school interactive event was held at St. Monica’s Senior High School at Asante Mampong in Ghana. The event was at a request of the host teacher who has just taken over the responsibility of the TAHMO Station.

It was a short and successful event. The opportunity was to provide students with the following:

  1. Brief background of TAHMO and its activities;
  2. TAHMO station – parts and how it works, type of data collected and access to the data;
  3. Importance of weather stations and climatic data; and the
  4. School-2-School Initiative.

The students and teachers were made aware of TAHMO and its activities. TAHMO operates 600+ Automatic weather stations on the African continent. These stations are located in 23 countries in Africa. TAHMO supports all the national meteorological agencies that it works with by providing access to its data.

TAHMO stations collect data for all the weather parameters – solar radiation (sunshine hours), rainfall, wind speed, wind direction, temperature, relative humidity, and atmospheric pressure. These sensors were pointed out to them as well as the data logger that stores and transmits the data.

Climate or weather data borders on security, as reliable and accurate data, help save the environment, lives, and properties. Weather-related disasters like flooding and drought impact can be minimized with accurate and reliable data. This will help provide adequate warning to the people in the affected region, area, or community ahead of the impending disaster. The students were made to understand and appreciate these as critical use of weather or climatic data.

The sch2sch Initiative is the platform designed to link or connect the schools that host TAHMO stations. To ensure this, access to the data from the station in the school is given, educational materials to support teaching and learning and regular interaction sessions are also provided. This is to ensure the station is not detached but facilitates learning at the school.

The TAHMO school-2-School program brings excitement as TAHMO host schools are informed, educated, and entertained on this platform.

St. Monica’s Senior High School is a single-sex (girls) school located at Asante Mampong in the Ashanti Region of Ghana. It is one of the top schools in the region and the country at large. It offers avenues for students to study science, business, and arts. The school became a TAHMO school in 2017 when it hosted a station.


My name is Cyuzuzo Honore, a coordinator for TAHMO in Rwanda.

I had an idea of developing weather information service for student in Rwanda. The idea won me a grant.

It started at a challenging time in 2020: COVID-19 hit. In Rwanda, TAHMO activities (especially those that involved travelling) were disrupted. During the first months of COVID there was a lot of fear since only little information on the virus was available. But as days went by, these informations became available; we knew how to protect ourselves and eachother which reduced the fear we all felt at first. But still Rwanda – my country – was under travel restrictions.

Mid-August I got to know about LOOP ACCELERATOR – an incubation program for Education Startups. I have long had a vision to improve climate literacy in the younger generation. With motivation from TAHMO’s SCHOOL – 2 – SCHOOL program, I envisioned developing a climate information platform. My Idea was to was to develop a portal with this information, then add some climate change mitigation and adaptation skills on the online platform that will be accessible to Rwandan schools.

Severe Weather Consult, TAHMO’s sister company in Rwanda, has a platform called iHEWA, whose goal is to enhance accessibility of weather information services. Among the targets of the platform are the students – they interact, learn and experiment local weather data which enhances their knowledge on climate change mitigation and adaptation. We strongly believe education is an essential element of the global response to climate change.

I submitted my concept and it won a grant. I spent 3 months in Loop accelerator. It was great opportunity to share experience with other more than 10 startups in Education including some already in the market. It was also a milestone to let Rwanda ICT Chamber, GIZ, SMART Africa get to know what we are doing as TAHMO in closing the gap by providing accurate and efficient Meteorological data. In addition, Loop accelerator grant us 800 USD in total that helped us develop IHEWA Online platform (click to visit ihewa).

IHEWA will be as online library for climate literacy for young generation to start act on climate change action plan. Also, IHEWA will be like a tool for schools while they are teaching climate change mitigation and adaptation. A vast online platform that will be including climate science lesson plans, climate change mitigation and adaptation skills and climate change risk reduction tips.

In the Lake Kivu region, water erosion is the main driver for soil degradation, but observational data to quantify the extent and assess the spatial-temporal dynamics of the controlling factors are hardly available. In particular, high spatial and temporal resolution rainfall data are essential as precipitation is the driving force of soil erosion. In this study, we evaluated to what extent high temporal resolution data from the TAHMO network (with poor spatial and long-term coverage) can be combined with low temporal resolution data (with a high spatial density covering long periods of time) to improve rainfall erosivity assessments. To this end, 5-minute rainfall data from TAHMO stations in the Lake Kivu region, representing ca. 37 observation years, were analyzed. The analysis of the TAHMO data showed that rainfall erosivity was mainly controlled by rainfall amount and elevation and that this relation was different for the dry and wet seasons. By combining high and low-temporal resolution databases and a set of spatial covariates, an environmental regression approach (GAM) was used to assess the spatiotemporal patterns of rainfall erosivity for the whole region. A validation procedure showed relatively good predictions for most months (R2 between 0.50 and 0.80), while the model was less performant for the wettest (April) and two driest months (July and August) (R2 between 0.24 and 0.38). The predicted annual erosivity was highly variable with a range between 2000 and 9000 MJ mm ha−1 h−1 yr−1 and showed a pronounced east–west gradient which is strongly influenced by local topography. This study showed that the combination of high and low-temporal-resolution rainfall data and spatial prediction models can be used to improve the assessments of monthly and annual rainfall erosivity patterns that are grounded in locally calibrated and validated data.

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L’Observatoire Hydrométéorologique Trans-Africain (TAHMO) est une association à but non lucrative qui cherche à développer un réseau dense de stations météorologiques sur le continent africain. Cela se traduit sur le terrain par l’installation de stations météorologiques automatiques, robustes et efficaces. TAHMO opère actuellement dans les régions centrales, orientales, occidentales et australes de l’Afrique et compte actuellement plus de 500 stations installées reparties dans cinq (05) Zones.

Dans la zone 2, TAHMO opère dans sept (07) pays dont le Burkina, le Mali, le Niger, le Sénégal, la Centrafrique, le Tchad et le Cameroun. La Zone 2 compte à ce jour plus de 70 stations.

TAHMO a pour objectif de fournir un taux de fonctionnement de 95% sur l’ensemble de son réseau de stations météorologiques à tout moment afin d’assurer une disposition des données de qualités et continues. Afin d’atteindre ces objectifs TAHMO souhaite renforcer son équipe avec un technicien ou un ingénieur de terrain.

Le travail se fait principalement sur le terrain où les stations sont installées et implique donc des déplacements. La personne pressentie, une fois sélectionnée, Co-assurera l’entretien des quarante-trois (43) stations installées actuellement au Mali, ce nombre est appelé à évoluer rapidement sachant que l’objectif de TAHMO est l’installation d’environ vingt mille stations (20 000) stations météorologiques automatiques sur le continent.

La langue principale de fonctionnement de l’organisation à but non lucrative TAHMO est l’anglais, ainsi la compréhension et la pratique de l’anglais et du français sont indispensable.

Le technicien ou l’ingénieur de terrain représente TAHMO sur place, il coordonne les activités de  TAHMO sous la supervision du directeur régional de la Zone 2. Il devra :

  1. Assurer l’installation des stations météorologiques, leurs maintenances ainsi que la promotion des activités de TAHMO au Mali.
  2. Maintenir un taux de fonctionnement d’au moins 95% pour toutes les stations sous sa supervision ;
  3. Assurer la liaison avec le superviseur régional (basé à Ouagadougou, Burkina Faso), le directeur des opérations et le Directeur General de TAHMO
  4. Faire un rapport hebdomadaire au directeur régional sur les performances et l’installation des stations (évaluation QA/QC),
  5. Entretenir un journal des activités journalières, hebdomadaires et mensuelles réalisées et prévisionnelles;
  6. Tenir à jour les métadonnées de toutes les stations qui vous sont assignés, y compris les photos et les rapports de chaque visite de site en utilisant un journal de bord et/ou les outils QA/QC en ligne de TAHMO ;
  7. Veiller à ce que toutes les stations relevant de sa compétence soient visitées au moins une fois par an et plus si nécessaire pour entretenir, réparer ou remplacer les stations.
  8. Entretenir les outils nécessaires aux opérations sur le terrain et tout autre actif, le cas échéant ;
  9. Superviser efficacement et effectivement les hôtes locaux des stations ;
  10. Soutenir l’équipe TAHMO pour améliorer les programmes de contrôle et d’assurance de la qualité ;
  11. Assurer la liaison avec les autres membres de l’équipe, y compris le directeur régional, le directeur général et le directeur des opérations pour superviser et former les nouveaux stagiaires ;
  12. Aider la direction générale à établir, maintenir et renforcer des liens formels et informels efficaces avec les partenaires clés, notamment Mali-Météo, les ministères et organismes gouvernementaux concernés, les autorités locales, les principaux décideurs et les autres parties prenantes en général, afin d’échanger des informations et des points de vue et de s’assurer que TAHMO fournit la gamme et la qualité appropriées de services nécessaires ;
  13. Commercialiser activement les services et produits de TAHMO au Mali et dans d’autres pays qui pourraient vous être assignés ;
  14. Soutenir les activités du programme School2school au Mali;
  15. Soutenir TAHMO afin de se positionner stratégiquement pour recevoir suffisamment de fonds par le biais de projets, de services et de produits afin d’améliorer sa croissance au Mali;
  16. Veiller à ce que TAHMO respecte toutes les lois locales, y compris le paiement de toutes les taxes pertinentes ;
  17. Effectuer d’autres tâches à la demande du directeur régional ou de la Direction Générale.

Lignes hiérarchiques

Le Technicien ou l’ingénieur de terrain relève directement du directeur régional, du directeur des opérations et du Directeur Général.


  • Un Master ou niveau d’enseignement supérieur (minimum DEUG 2) en météorologie, physique, mathématique, génie civil, génie électrique/électronique, génie informatique, informatique, sciences de l’environnement et programmes connexes.
  • La capacité à écrire et à parler un excellent anglais.


Les candidatures, les lettres de motivation et les curriculum vitae (CV) doivent être envoyés par courrier électronique au plus tard le 19 Février 2021 à 23h59 à l’adresse suivante.



Le directeur régional

TAHMO Zone 2

Ouagadougou-Burkina Faso
Tel : +226 70 16 94 23