With the ocean and atmosphere system now locking into a more coupled +ENSO pattern in October, our ENSO Whisperer model has nudged higher with the maximum strength of the event and longer with the duration of El Niño, which is now predicted to last into the spring while attenuating slightly.
A weak, central Pacific El Nino, a low point on the solar cycle, and a favorable Pacific mid-latitudes set-up mean relatively elevated chances of above normal precip for the southern tier, mid-Atlantic, and Ohio Valley between November and January, along with a drier tilt in the Northern Plains. Expect normal to somewhat below normal temperatures centered over the Plains and across the southern tier.
The equatorial Pacific remains in a neutral-positive state. While atmospheric measures of ENSO state have shifted slowly towards Niño-like teleconnections, SST anomalies themselves have changed little over the past 6 weeks. This favors slow development of a Central Pacific +ENSO event over the next 2-3 months, per our ENSO Whisperer model.
WeatherTiger’s August update to our 2018 hurricane season presents only minor changes from our initial forecast issued in late May for overall activity of between two-thirds and three-quarters of an average year. Cooler than average waters in key regions of the Atlantic, a developing El Niño in the Pacific, and much stronger than average trade winds in the Caribbean this summer confirm these signals.
The equatorial Pacific remains in a neutral-positive state. While atmospheric measures of ENSO state are slowly but steadily shifting towards Niño-like teleconnections, SST anomalies themselves cooled slightly over the past 6 weeks. This favors the slower development of a Central Pacific +ENSO event this fall.
The equatorial Pacific remains in a neutral state at present. However, atmospheric measures of ENSO state are beginning to tilt heavily towards Niño-like patterns. This trend is likely to intensify over the next six weeks as the Pacific flirts with weak El Niño territory in August.
The equatorial Pacific is in a neutral state, with atmospheric measures of ENSO divided between Niña and Niño-like patterns. WeatherTiger’s proprietary ENSO Whisperer is a little quicker to move the Pacific towards a weak El Niño, with the development of a weak or moderate +ENSO over the fall and winter of 2018 continues to be our preferred forecast solution.
A look ahead to the 2018 hurricane season reveals a below normal year in terms of total activity and U.S. landfall risk is the most likely outcome. Uncertainty remains elevated at this lead time due to lingering questions on how rapidly cooling Atlantic SSTs will evolve over the summer.
A favored pattern for the summer (May-July) period based on historical analogs and our proprietary modeling is a volatile pattern with a tendency for ridging over the Southern Plains. All else equal, this means a warmer and drier summer than average in the Plains and western corn belt, with more normal but still tilting warm conditions further east.