Very Warm SSTA and Hot/dry East China Upper Ridge Risk Heading Into August
07/18/2022, 5:18 am EDTWetter Medium-range for Central U.S. But Upper-level Ridge Over U.S. Corn Belt in 15 days
07/20/2022, 4:48 am EDTHighlight: Weak La Nina continues; subs-surface has started to cool-off again.
Fig. 1: The 12-week Nino SSTA observations reveal La Nina 2020-22 is barely hanging on!
Discussion: Weak La Nina continues to hang on in the equatorial East Pacific. A moderate intensity La Nina was present through early June but warming of the subsurface has weakened La Nina in recent weeks. The Nino34 SSTA is at -0.6C just-within the La Nina threshold (Fig. 1). The subsurface warming has started to reverse (Fig. 2). During the past 7-10 days the upper ocean heat east of the Dateline is now cooler than normal (again). The cooler change suggests La Nina will continue. The latest NCEP CFS V2 Nino34 SSTA forecast indicated La Nina will regain strength during the next several months before returning to neutral phase in 2022 (Fig. 3).
Fig. 2: Upper ocean heat across the equatorial Pacific reveals recent warming.
Fig. 3: The latest NCEP CFS V2 Nino34 SSTA forecast.