A titanic Madden Julian oscillation episode shifting across the tropical Pacific has weakened trade winds likely causing an early demise to La Nina by early northern hemisphere springtime. The MJO is shifting east and will cause an influx of tropical/subtropical moisture to the U.S. pattern over the next 1-2 weeks.
The moisture influx to the U.S. pattern will ride a semi-permanent front boundary separating unseasonably mild-to-warm air across the East and South U.S. for the remainder of February from deep cold anchored in the Northwest U.S. to Great Plains. The axis of heavy precipitation is most dramatically indicated by the overnight operational GFS model which indicates 10+ in. of rain the next 15 days from Arkansas to Tennessee (Fig. 1).
The wet forecast is projected across an area already turning quite wet in February. Heavy precipitation is reversing previously dry soil conditions in the Mid-South/Tennessee Valley areas (Fig. 2) in February. The trend will continue and expand.
Fig. 1: The GFS 15-day precipitation forecast.
Fig. 2: The February soil moisture change analysis.