Sharp Negative Southern Oscillation Index as El Nino Climate Developing

Fig. 1: Vigorous negative phase southern oscillation index is developing, a sign that El Nino climate is evolving quickly.

Discussion: The long-standing 2020-23 La Nina climate pattern is fading. The southern oscillation index has steadily shifted into the El Nino-like negative phase during May and whopping daily values of -6 the past couple days (Fig. 1) partially influenced by a West Pacific typhoon. The strong -SOI is characteristic of a developing El Nino climate. The 15-day upper air pattern forecast across North America and Europe is indicative of an El Nino climate featuring subtropical low-pressure troughs while the middle/high latitudes are beneath dry and warm high-pressure ridge areas (Fig. 2). The 15-day rainfall forecast by GFS for the U.S. features more dryness in the Midwest States while Central and Northern Europe plus the spring wheat areas in Western Russia are dry (Fig. 3-4). The latest Europe Drought Monitor identifies the Southwest Europe/Northwest Africa harsh drought with a Drought Warning in effect for the Southern Black Sea region (Fig. 5).

Fig. 2: The 15-day upper air pattern projected across North America and Europe by the GFS identifies a southern trough/northern ridge El Nino climate pattern.

Fig. 3-4: The GFS 15-day rainfall anomaly forecast across the U.S. and Europe/Western Russia.

Fig. 5: The latest Europe Drought Observatory drought analysis.