{"id":"station-daily-climate","slug":"station-daily-climate","name":"Station Daily Climate Dataset","description":"Daily precipitation, maximum and minimum air temperature and snow depth from 146 long-record stations across eleven jurisdictions, reaching back to 1814. Every station stands within thirty kilometres of a river gauge, borehole, monitoring station or reservoir that Hydrionis already reports, and carries the measured distance to it.","methodology":"Collected from NOAA’s GHCN-Daily, which assembles national meteorological services into one quality-controlled record. Stations were selected by length of precipitation record and by distance to a Hydrionis measurement point; the selection is written down and published rather than decided afresh on each run, so it can be reviewed. Values carrying any GHCN quality flag are not stored, because a value its own publisher doubts cannot be shown on a chart that has no way to express doubt. The missing marker is skipped rather than stored as zero, which matters most for snow depth, where stations stop reporting through summer and a zero would be a measurement nobody made.","domains":["precipitation","temperature","snow-ice"],"metricIds":["precipitation-daily","temperature-max-daily","temperature-min-daily","snow-depth"],"subjectScope":"146 GHCN-Daily stations in the UK, Ireland, France, the Netherlands, Germany, Poland, Sweden, Finland, Norway, Canada and the United States","cadence":"daily","version":"1.1.0","released":"2026-08-31","changelog":[{"version":"1.1.0","date":"2026-08-31","summary":"A hundred more long-record stations, selected by the rule that was already documented.","additions":["One hundred additional GHCN-Daily stations, taking the dataset from forty-six to 146 and its coverage from nine jurisdictions to eleven, adding Norway and Canada. Every one carries between 135 and 168 years of daily precipitation, and the added stations carry precipitation alone.","The selection rule did not change. The list had been capped at forty-six below what its own criteria admit — still reporting, within thirty kilometres of a Hydrionis measurement point, sixty kilometres apart from each other — which together admit 1,145 stations. The hundred longest records were taken; the remainder are recorded as an acquisition gap rather than absorbed, because each is a daily series running for a century."]},{"version":"1.0.0","date":"2026-08-27","summary":"First release.","additions":["Daily precipitation, maximum and minimum temperature and snow depth for forty-six long-record stations."]}],"limitations":["A daily total belongs to the publisher’s observation day, which differs between networks and has sometimes changed within one station’s record. Single days are not reliably comparable across countries.","Rain gauges under-catch in wind and snow, most severely at exposed and upland sites, so long records contain changes caused by the site rather than the weather.","These are point measurements. A station is not its region, and an unweighted average of whichever gauges exist is not an area rainfall figure.","Distance to the nearest Hydrionis measurement point is a stated spatial fact. It is not a claim that the station lies in that gauge’s catchment."],"context":{"hydrionisClass":"water-driver","whyHeld":"Rainfall, temperature and snow are what make rivers do what they do. A flow record on its own can say what happened and never why; the same record beside the rain that fell on the same days can. These are not measurements of water in the river — they are measurements of what arrived above it.","waterRelevance":["River flow and the shape of a hydrograph","Groundwater recharge","Reservoir inflow","Drought onset and recovery","Snowmelt-driven seasonality in Nordic and Alpine basins"],"suitableUses":["Showing what the weather was doing during a flood, a drought or a low-flow period","Lagged association between rainfall and flow at a nearby gauge, with the distance stated","Long-run climatology at a single station, where the record is genuinely continuous"],"unsuitableUses":["Area or catchment rainfall — that needs a gridded product, not an average of the gauges that happen to exist","Attributing a flow event to a specific rainfall event without catchment evidence Hydrionis does not hold","Comparing single days between countries, where observation-day conventions differ"],"joinDimensions":[{"kind":"measured-proximity","on":"Great-circle distance from the station to the nearest Hydrionis measurement point, stated per station and never more than 30 km","limitation":"Proximity is not catchment membership. A station 3 km from a gauge may sit outside its catchment entirely, and rain falling at the station may never reach that gauge."},{"kind":"time-only","on":"Shared daily and monthly periods with any other Hydrionis series","limitation":"A shared time axis supports showing two series together and nothing else. Two series covering the same years are not thereby related."}],"relationshipConfidence":"proximate","eligibility":{"api":true,"download":true,"overlay":true,"publicPage":false}},"observationCount":10635099,"seriesCount":267,"subjectCount":146,"from":1814,"to":2026,"sourceIds":["noaa-ghcn-daily"],"units":["mm","°C"],"redistributable":true,"commerciallyReusable":true,"citation":"Hydrionis (2026), Station Daily Climate Dataset, version 1.1.0. Retrieved from https://hydrionis.com/data/datasets/station-daily-climate/","downloads":[{"file":"/downloads/observations-precipitation-noaa-ghcn-daily.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 1 of 7 (1,000,000 rows)"},{"file":"/downloads/observations-precipitation-noaa-ghcn-daily-part2.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 2 of 7 (1,000,000 rows)"},{"file":"/downloads/observations-precipitation-noaa-ghcn-daily-part3.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 3 of 7 (1,000,000 rows)"},{"file":"/downloads/observations-precipitation-noaa-ghcn-daily-part4.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 4 of 7 (1,000,000 rows)"},{"file":"/downloads/observations-precipitation-noaa-ghcn-daily-part5.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 5 of 7 (1,000,000 rows)"},{"file":"/downloads/observations-precipitation-noaa-ghcn-daily-part6.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 6 of 7 (1,000,000 rows)"},{"file":"/downloads/observations-precipitation-noaa-ghcn-daily-part7.csv","format":"CSV","label":"precipitation observations from NOAA NCEI, part 7 of 7 (683,264 rows)"},{"file":"/downloads/observations-temperature-noaa-ghcn-daily.csv","format":"CSV","label":"temperature observations from NOAA NCEI, part 1 of 4 (1,000,000 rows)"},{"file":"/downloads/observations-temperature-noaa-ghcn-daily-part2.csv","format":"CSV","label":"temperature observations from NOAA NCEI, part 2 of 4 (1,000,000 rows)"},{"file":"/downloads/observations-temperature-noaa-ghcn-daily-part3.csv","format":"CSV","label":"temperature observations from NOAA NCEI, part 3 of 4 (1,000,000 rows)"},{"file":"/downloads/observations-temperature-noaa-ghcn-daily-part4.csv","format":"CSV","label":"temperature observations from NOAA NCEI, part 4 of 4 (320,200 rows)"},{"file":"/downloads/observations-snow-ice-noaa-ghcn-daily.csv","format":"CSV","label":"snow-ice observations from NOAA NCEI (717,034 rows)"}],"apiPath":"/api/v1/datasets/station-daily-climate.json","lastFetched":"2026-08-31","fields":[{"id":"precipitation-daily","name":"Daily precipitation","definition":"Depth of precipitation recorded at a single station over one observation day.","unit":"mm","nativeGeography":["monitoring-station"],"comparabilityNotes":"A daily total belongs to the publisher’s observation day, which differs between networks and has sometimes changed within one station’s record. Comparing single days across countries is therefore unreliable even where the gauges are equally good. Totals are also under-caught in wind and snow, most severely at exposed and upland sites."},{"id":"temperature-max-daily","name":"Daily maximum air temperature","definition":"Highest air temperature recorded at a station during one observation day.","unit":"°C","nativeGeography":["monitoring-station"],"comparabilityNotes":"Screen height, exposure and instrument type differ between networks and have changed over long records. Urban stations warm relative to rural ones as the settlement around them grows, which is a real change at that station but not a regional climate signal."},{"id":"temperature-min-daily","name":"Daily minimum air temperature","definition":"Lowest air temperature recorded at a station during one observation day.","unit":"°C","nativeGeography":["monitoring-station"],"comparabilityNotes":"Minima are more sensitive to local siting than maxima: a frost hollow reads several degrees colder than a slope a few hundred metres away, and that difference is real for the site but not transferable to its surroundings."},{"id":"snow-depth","name":"Snow depth","definition":"Depth of snow lying on the ground at a station at the time of observation.","unit":"mm","nativeGeography":["monitoring-station"],"comparabilityNotes":"Depth is not water content. A metre of fresh powder and 200 mm of old compacted snow can hold the same water, and only the second is close to melting. Snow-water equivalent is the metric that answers \"how much water is stored\"; this one answers \"how deep is it\". Depth is also strongly affected by drifting, so a single stake is a poor estimate of the surrounding area."}]}