INMET (Instituto Nacional de Meteorologia): Viçosa has an INMET climatological station (formerly located at the Federal University of Viçosa) that collected long-term weather data. The INMET climate normals (Normais Climatológicas) for 30-year periods provide the average monthly and annual precipitation. According to INMET’s 1991–2020 normals, Viçosa receives roughly 1,289 mm of rain annually, with a pronounced wet season in the austral summer and a dry season in winter【34†L67-L71】. For example, February averages around 160 mm of rainfall, while June–July average under 10–15 mm each (reflecting the winter dry period)【34†L67-L71】. These normals are calculated per WMO guidelines over a 30-year period【19†L133-L141】. INMET has published the 1991–2020 normals on its portal (including an Excel file with monthly precipitation for each station, where Viçosa is listed) – this can be accessed via the INMET “Normais Climatológicas” downloads page【19†L133-L141】.
For historical time series, INMET’s BDMEP (Banco de Dados Meteorológicos) is the official database for station observations. Through the BDMEP web portal【5†L33-L41】, users can search for the Viçosa station and download data (after a free registration). Data are available as daily records which can be aggregated to monthly totals. The Viçosa conventional meteorological station operated from the 1940s until it was closed in January 2018【5†L191-L193】, so the BDMEP archive contains decades of rainfall measurements up to 2017. The Federal University of Viçosa also provides annual meteorological bulletins (in PDF) compiled from the INMET station data【5†L33-L41】. These bulletins (available on the UFV Meteorologia website) list monthly and annual rainfall each year, which can be useful for validating historical values against the chart. For any usage beyond research, INMET should be cited or consulted as the data source【5†L35-L41】.
ANA (Agência Nacional de Águas e Saneamento Básico): Brazil’s National Water Agency maintains a network of pluviometric stations across the country that monitor rainfall, often associated with river basins. ANA’s network includes thousands of rain gauges (approximately 2,717 stations for rainfall monitoring nationwide)【9†L11-L18】. It’s likely that one or more ANA-operated rain gauges are in or near Viçosa. You can use ANA’s HidroWeb portal (SNIRH system) to find and download historical precipitation data: on the “Séries Históricas de Estações” page, search by station name (e.g. Viçosa), by municipality, or by basin【9†L5-L13】. Once the station is identified, you can retrieve daily or monthly rainfall series, usually available as CSV or Excel. ANA also provides open-data access – for example, through its dadosabertos portal – where bulk rainfall data can be downloaded or accessed via APIs【9†L11-L18】. If an official ANA rain gauge in Viçosa is available, its dataset would serve to corroborate monthly averages (though note that values might differ slightly if the location or period of record differs). In summary, ANA’s HidroWeb is a key resource for obtaining observed rainfall time-series from hydrological stations in the Viçosa area, complementing the INMET station data.
Obtaining soil moisture information for Viçosa from official Brazilian sources is more challenging, as there isn’t a long-running public in-situ soil moisture record analogous to rainfall. Neither INMET nor ANA routinely publish direct soil moisture measurements for specific locations. However, model-based soil moisture indices and water balance data are available:
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INMET – Soil Water Balance (Sisdagro): INMET’s agrometeorological system (Sisdagro) provides soil water balance analyses. For example, the Climatological Water Balance product offers monthly climatology of soil water storage and deficits, calculated using average climate data. The Sisdagro portal allows downloading data (in XLS format) which includes variables such as percent soil moisture storage (“Armazenamento (%)”), monthly precipitation, evapotranspiration, and water surplus/deficit for a standard soil capacity【37†L38-L47】【37†L64-L72】. These values are computed via the Thornthwaite/Mather method (assuming a default soil water holding capacity, e.g. 100 mm of available water as noted in the metadata)【37†L64-L72】. While this is a generalized model (not a direct measurement), it provides a climatological soil moisture pattern. You could use it to see how soil moisture typically rises and falls in tandem with Viçosa’s rainy and dry seasons. For instance, during the peak of the rainy season the model would show soil water storage near 100% capacity, whereas in late winter it shows significantly depleted soil moisture.
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Brazilian Drought Monitor: ANA, in partnership with other institutions (like CEMADEN, INMET, etc.), operates the Monitor de Secas (Drought Monitor) which incorporates soil moisture indices to assess drought conditions. This is a qualitative product (monthly maps and reports) that uses indicators including soil moisture anomaly to categorize drought intensity. While it doesn’t provide a raw time-series for Viçosa specifically, it is an official resource that contextualizes soil moisture at regional scale. The Monitor de Secas portal publishes monthly bulletins and GIS maps – for example, showing areas with soil moisture deficits. This can be useful if one needs to compare how anomalously dry or wet a given month’s soil moisture was relative to normal, complementing the precipitation data.
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Research and Other Data: In absence of a direct official dataset, researchers sometimes rely on remote sensing and reanalysis for soil moisture. Although not from Brazilian agencies, global products (NASA’s or ESA’s satellite soil moisture datasets, or reanalysis like ERA5) can be used to estimate historical soil moisture for the region. Additionally, Brazil’s disaster monitoring center CEMADEN has installed in-situ soil moisture sensors in limited locations (primarily for landslide-prone areas)【15†L1-L8】, but Viçosa is generally not part of that network. If detailed soil moisture measurements are needed, one may need to consult academic studies or local agronomic stations. For example, a study at UFV might report soil moisture measurements under specific conditions【15†L1-L8】, but these are not maintained as continuous open data streams.
Accessing Soil Moisture Data: For practical purposes, the INMET Sisdagro water balance download is the most accessible official source. On the Sisdagro site, under Climatologia -> B.H. Climatológico Mensal, you can download an Excel file of normal monthly water balance components【37†L38-L47】. This file will show how much rainfall, evapotranspiration, and soil water storage to expect on average each month (which reflects soil moisture levels). By comparing the precipitation chart to these data, you can substantiate, for example, that Viçosa’s soils reach maximum moisture at the end of the rainy season and then experience progressive drying from April to September (with large moisture deficits in winter). Any metadata (like soil field capacity assumption, etc.) is usually noted in the file or accompanying documentation【37†L64-L72】.
In summary, while precipitation data for Viçosa are directly available from Brazilian official sources (INMET and ANA) in CSV/Excel formats, soil moisture information comes indirectly through modeled climatological water balance or drought indices. By leveraging INMET’s climate normals and data portals, one can obtain the monthly rainfall averages (to validate the chart’s values) and by using INMET/ANA’s agricultural and drought monitoring tools, one can retrieve corresponding soil moisture indicators. Always consult the provided metadata – for instance, INMET documentation on how normals were calculated【19†L133-L141】 or the assumptions in the water balance model – to ensure the data is interpreted correctly when comparing to the chart.
Sources:
- INMET Climatological Normals (1991–2020) – Monthly & Annual Precipitation for Viçosa, MG【34†L67-L71】【19†L133-L141】
- UFV/INMET Viçosa Station Data (Conventional Station records 1942–2017)【5†L33-L41】【5†L191-L193】
- ANA HidroWeb – Historical Rainfall Series (station search and open-data download)【9†L5-L13】【9†L11-L18】
- INMET Sisdagro – Soil Water Balance Climatology (monthly soil moisture, precipitation, etc.)【37†L38-L47】【37†L64-L72】
- Brazilian Drought Monitor – Soil Moisture Index and Drought Maps (qualitative, for regional context)【15†L1-L8】 (via ANA/CEMADEN)