Calibrated Subseasonal Two-category precipitation real-time forecasts from the Subseasonal eXperiment (SubX)
The default map shows the latest forecast for weeks 2-3 ahead (i.e. the 14-day Saturday-Friday target period, 9 to 22 days after the forecast is issued), as probability of above-median. Previous forecasts can be viewed through the control bar menu.The weeks 3-4 forecast (i.e. the 14-day target period, 16 to 29 days after the forecast is issued) is also available. New forecasts are issued weekly on Fridays.
When navigating to a forecast of which Target Period is in the past, a smaller side map shows a verification of the forecast as the observed tercile values according to the training period of the calibration of the forecast. Before May 1, 2021, the climatological period is 1999-2014; After May 1, 2021, the climatological period is 1999-2016.
The probabilistic forecasts shown here are obtained from the statistical calibration of three models (NCEP CFSv2, NCEP GEFS, and NOAA/ESRL FIM HYCOM, each run on Wednesdays) from the SubC database which are combined with equal weight to form multi-model ensemble precipitation median probabilities forecasts. Individual model forecasts are calibrated separately for each point, start and lead using Extended Logistic Regressions (ELR; Vigaud et al, 2017) based on the historical performance of each model, and thus provide reliable intra-seasonal climate information in regards to a wide range of climate risk of concerns to the decision making communities and for which subseasonal forecasts are particularly well suited.
Subseasonal-to-seasonal forecasting techniques are still under development. This Maproom shows the type of experimental forecast information currently being created at these time scales in real time.
References:
Forecast: Global 1˚ Multi-Model Ensemble forecasts median-exceedance probabilities available here obtained from the statistical calibration of three models (NCEP CFSv2, NCEP GEFS, and NOAA/ESRL FIM HYCOM) from Subseasonal Experiment (SubX).
Historical precipitation: Global 1˚ NOAA UNIFIED precipitation data set, historical and real-time available here.
Contact help@iri.columbia.edu with any technical questions or problems with this Map Room.