Econintersect Weather and Climate Forecast Update
Written by Sig Silber
The latest reports indicate that warm water continues to be moving towards the coast of Ecuador, a condition that produces an El Nino pattern which has a high probability of impacting our weather next winter but it is not yet definitive. There is a slight hint that it may be a brief El Nino but it is too soon to have any confidence in that.
There are also some changes in the short term forecast 6 - 14 days. The major cold intrusion into the center of the U.S. has been removed from the forecast and we now have a split flow with progression of systems in the Northern part of the U.S. less related to the flow of systems in the Southern part of the U.S.
From the Australia Bureau of Meteorology - El Niño likely to develop in winter. Issued on Tuesday 8 April 2014
"It is now likely (estimated at a greater than 70% chance) that an El Niño will develop during the southern hemisphere winter. Although the El Niño–Southern Oscillation (ENSO) is currently neutral, surface and sub-surface ocean temperatures have warmed considerably in recent weeks, consistent with a state of rapid transition. International climate models surveyed by the Bureau indicate continued warming of the central Pacific Ocean in coming months. Most models predict sea surface temperatures will reach El Niño thresholds during the coming winter season.
El Niño is often, but not always, associated with below normal rainfall across large parts of southern and inland eastern Australia during the second half of the year. The strength of an El Niño does not always indicate how much it will influence Australian rainfall. Historically there are examples where weak events have resulted in widespread drought across large parts of Australia, while at other times strong events have resulted in relatively modest impacts. It is too early to determine the strength of this potential El Niño. Daytime temperatures tend to be above normal over southern Australia during El Niño.
The Indian Ocean Dipole (IOD) is currently in a neutral state. Model outlooks indicate the IOD will remain neutral through late autumn and early winter. The chance of a positive IOD event occurring will increase if an El Niño develops."
Remember that Australia is in the Southern Hemisphere and their seasons are reversed from those in the Northern Hemisphere