Madden Julian Oscillation To Intensify

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For the first time since November the Madden Julian oscillation is activated and intensifying in the equatorial Pacific Ocean into early February. The result is increased risk of excessive precipitation in the East-central U.S. and a mild climate pattern east of the Continental Divide as the final month of meteorological winter arrives.

Discussion: Over-the-weekend the MJO forecast continues to strengthen (Fig. 1). The GFS is strongest and indicates a robust MJO phase_7 next week. In the short-term MJO phase_6 is organizing (and strengthening). The implications are increased risk of significant precipitation in the East-central U.S. Initially, plenty of snow is involved but later in the two-week forecast rain is favored. The MJO phase_6/phase_7 forecast also favors a warmer than normal climate east of the Continental Divide. Plenty of mild and wet Pacific/Gulf of Mexico influence in the likely pattern ahead. The Western U.S. is the cold bias region helped by increasing snow cover.  

Globally, there is influence on Australia and South America given the emerging MJO phase_6/phase_7 regime. Slowly, a wet bias in Australia fades – likely by the middle third of February. The MJO shift favors increased anomalous wet climate across South America.

Above normal risk of tropical cyclone activity north and especially northeast of Australia in this pattern

The MJO phase_6/phase_7 regime should make La Nina weaker as trade winds ease and convection increases.