“The views expressed are those of the author and do not necessarily represent those of the National Weather Service.”
Please see links from the 6 June posting for current information. I am hopeful that time will allow me to present a more formal discussion next weekend, ~27 June. Whatever the case, the subseasonal dog (Rex the Rottweiler) is always watching!
The global ocean-land-atmosphere dynamical system remains tilted toward a weak El-Nino base state. Per WB (2009) measure of the GWO, the latter has particularly been the case since about mid-May. Having a contribution from frictional dissipation (negative global frictional torque) of anomalous zonal mean westerly wind flows propagating poleward into the midlatitude atmospheres, there is an on-going superimposed GWO/MJO 8-1 transition. In WB (2009) GWO and WH (2004) MJO phase spaces, the latter is probable to appear as another relatively minor orbit displaced toward octants 7-8-1. Phases 8-1 of the snr plots nicely depict the current global weather-climate system.
The equatorial Pacific Ocean basin is generally ~plus 0.5-1.0C warmer than normal. One important monitoring issue will be to see how much of an impact the recent strongest west Pacific WWB in roughly 2 years (~10-15m/s anomalies) has upon the thermocline during the next 1-2 months.
One regional scale response has been a convectively active Western Hemisphere, favoring deep tropical moisture transport into the central USA. I think the notion of most models to show retrogression of the trough-ridge-trough pattern across the lower 48 states during the next couple of weeks is reasonable. The latter is consistent with a brief circuit through phases 2-5 of the snr composites. By later week-2 into week-3, there may be a period of ridging around the west coast suggesting a "cool/wet trough" across the central and eventually portions of the eastern states. On average, phases 7-8 of the snr composites may best represent the global atmosphere the rest of boreal summer.