Performance of the NCEP model suite during DYNAMO October 2011-March 2012

A collaborative work between NCEP and the University of Maryland/ESSIC is assuring the tailoring of operational realtime forecast products from the NCEP suite of dynamical forecast to support DYNAMO. The NCEP models utilized to provide operational forecast guidance to the DYNAMO campaign included the high resolution Global Forecast System (GFS), the Global Ensemble Forecast System (GEFS) and the coupled Climate Forecast System (CFS). We first introduce specifications of the modeling systems and our forecast product strategy. Then we evaluate the prediction skill for several variables (Outgoing Longwave Radiation (OLR), precipitation and 850-hPa and 200-hPa winds) during the DYNAMO campaign. As of the present day (11/11/11), one complete cycle of the MJO (both enhanced and suppressed phases) was observed across the DYNAMO array during October 2011. This MJO event was correctly forecast to enter and cross the Indian Ocean. Contributing to this prediction was observation of anomalously warm sea surface temperatures associated with a strong eastward equatorial jet covering the central and western equatorial Indian Ocean. In the final part of this talk we show reasons for this ocean behavior and we discuss the potential role of ocean dynamics as a link in the chain of events that leads to the genesis and propagation of the MJO.