What is made here
Wine colours
Colours the rules allow. Pick a colour to filter the rules and grapes below.
Where it is
Seyssel in France
- Latitude
- 45.9°–46.0° N
- Vineyard altitude
- 290 m to 405 m
- Delimited vineyard land
- 1,838 ha
The delimited vineyard parcels themselves, so the shape is patchy: only land within them may grow the wine. Boundary: INAO parcel delimitation (Licence Ouverte); nearby parcels drawn as one block, with less detail for larger appellations. Country outlines: Natural Earth. Dots on the zone map are the vineyard points used for climate.
Showing every colour The colour filter changes the rules and grapes. Climate, vintages and soils describe the vineyards, so they stay the same.
01 · What the law says
The rules
Limits on grapes, yields, ripeness and ageing that every wine labelled Seyssel must meet.
Blend rules
Seyssel
- ≥ 75% Molette · Main grape
- ≥ 10% Altesse · Main grape
- – Chasselas · Allowed
At least 9 months' ageing; release from 9 months after tirage.
In the vineyard and cellar: rules for every wine
6,000
Vines per hectare, minimum
Training
Systems allowed
gobelet; éventail; cordon de Royat simple; cordon de Royat double
02 · Climate fingerprint
The climate
The growing season averages 16.5 °C, intermediate on Gregory Jones's scale, with 1,399 growing degree days (Winkler II).
The average year 1991–2020, vineyards at about 370 m
Monthly mean, °CRain, mmGrowing season
- Growing-season temperature
- 16.5 °C
- Intermediate · 15–17 °C (Jones)
- Growing degree days
- 1,399
- Region II: 1,389–1,666 degree days
- Growing-season rain
- 965 mm
- Of 1,655 mm a year
- Harvest rain
- 268 mm
- September–October
Copernicus ERA5-Land monthly averages at 5 vineyard points (Vineyard point 1, 329 m; Vineyard point 2, 399 m; Vineyard point 3, 376 m; Vineyard point 4, 337 m; Vineyard point 5, 408 m), moved to each point's height from the model's terrain. Indices that need daily data are not captured yet. How the climate figures are made.
Lower confidence:Monthly reanalysis in complex terrain (height corrections up to 2.4 °C); absolute values may be several degrees out, year-to-year changes are more reliable.
Closest climates in the database
Picked by the data, not by hand: the profiles nearest on season warmth (counted twice), degree days, rain, ripening-month nights and day–night range. Neighbours within 30 km are left out, as they share the same weather.
1. Sforzato di ValtellinaVery similarCompared with Seyssel: same season warmth, similar rain.
2. TrentoVery similarCompared with Seyssel: same season warmth, similar rain.
3. RamandoloVery similarCompared with Seyssel: same season warmth, similar rain.
Growing-season temperature
Growing degree days
Growing-season rain
03 · Year by year
35 vintages
Each column is one growing season: heat above or below the 1991–2020 average, and rain at harvest. Pick a year for the details.
Warmer than averageCooler than averageHarvest rain (Sep–Oct)Average harvest rain, 268 mm
2025
- Growing-season temp.
- Growing degree days
- Harvest rain
- Growing-season rain
- September nights
- Hot days and frosts
Seasons are labelled by harvest year (April–October). Year-to-year changes from ERA5-Land; tested against station records in Alto Adige (r = 0.94 for season temperature at Bolzano). Rain varies more locally, so treat single-season rain with some caution. Vintage ratings, harvest dates and frost or hail events have places in the data model but are not loaded yet.
04 · Where the numbers come from
Sources
- A geospatial inventory of regulatory information for wine protected designations of origin in Europe · Candiago et al., Scientific Data 9, 394 (2022); Eurac Research · CC0
- Quality wines in Italy and France: a dataset of PDO specifications · figshare 25393261 · CC BY 4.0
- ERA5-Land monthly averaged data (reanalysis-era5-land-monthly-means) · Copernicus Climate Change Service (C3S), Climate Data Store · CC BY 4.0 (Copernicus licence)
- OpenStreetMap vineyard areas (landuse=vineyard), from Geofabrik country extracts · OpenStreetMap contributors · ODbL 1.0
- Copernicus DEM GLO-90 (AWS open data tiles) · European Space Agency / Copernicus · Copernicus DEM licence
- Cahier des charges: Seyssel (Cahier des charges de l'appellation d'origine contrôlée Seyssel homologué par décret décret n°2015-835 du 7 juillet 2015 - BO n°29 du 16 juillet 2015) · Ministère de l'Agriculture (Bulletin officiel), as linked by INAO · Official act
- Délimitation parcellaire des AOC viticoles de l'INAO · Institut national de l'origine et de la qualité (INAO), via data.gouv.fr · Licence Ouverte / Open Licence (Etalab)
- Climate profiles calculated by Vinous: method
Still to check (3)
- Generated from EU reference data: check against the current product specification.
- From the specification: Dry altesse wines may have up to 8 g/l sugar, and demi-sec up to 15 g/l, depending on total acidity; the demi-sec type is governed separately in the text and added as a product. The sparkling cuvée needs at least 75% molette and 10% altesse base wines. Irrigation is not mentioned.
- National tier (DOC/DOCG) not captured yet; rules extracted from the specification text.