An overview of how to work with accumulated data values such as total precipitation.
Certain data variables returned by the Spire Weather API represent forecast-total accumulated values since the start of the forecast, rather than fixed-interval accumulations (e.g., 6-hour or 24-hour values).
Examples of Accumulated Variables¶
Basic Bundle
Total Precipitation
Renewable Energy Bundle
Surface Net Downward Shortwave Flux
Agricultural Bundle
Net Upward Longwave Flux at Top of Atmosphere
Surface Net Upward Longwave Flux
Surface Net Upward Shortwave Flux
Surface Net Downward Longwave Flux
Surface Net Downward Shortwave Flux
Interpreting the Data¶
Without post-processing, values from an accumulated variable only increase over the forecast time range, since they accumulate from the beginning of the forecast window.
With simple post-processing, you can compute the difference between each value and the preceding one. This yields the accumulation for each interval (e.g., 6-hour precipitation amounts).
Code Sample¶
A code sample using the Point API demonstrates how to create 6-hour accumulations from the forecast-total value by differencing the totals from adjacent lead times.