3:45PM Tuesday the 19th


There was a very encouraging update for the CPC this Morning.   They chat about the extreme IOD out over the Indian Ocean. That is bringing flooding to parts of Africa and drought to parts of Australia. They now expect a response to the mid latitudes which is surprising!

This post is pretty esoteric, however, I know that there are several Dweebs out there that they will be happy to read this discussion…..


From the CPC today:

The MJO remained active during the past two weeks, propagating rapidly across the Pacific before returning to the Western Hemisphere. During the past several days, the RMM index stalled over the Western Hemisphere. This slowdown is likely due to constructive interference between the MJO and the strong positive phase of the Indian Ocean Dipole (IOD). Dynamical model forecasts of the RMM index are mixed, although most depict weakening with no additional propagation to the eastern Indian Ocean or Maritime Continent during the next two weeks. In addition to the IOD which favors convection over Africa and the western Indian Ocean, robust Rossby wave activity and above-normal SSTs across the central Pacific may help generate additional convection that is “out of phase” with the current MJO event. This may be why some GFS and ECMWF ensemble members favor a quick return of the index to the Pacific. Based on these forecasts, the MJO is favored to play a diminishing role in the evolution of the tropical convective pattern over the outlook period. The IOD will likely become the “dominant mode” of tropical variability, and widespread convection over the Western Indian Ocean may teleconnect to the midlatitudes and help change the downstream pattern over North America with more “troughing across the West”. 

Dweeb Comment….For one thing, it this comes about….This is likely to bring some very cold weather to the Eastern Sierra in December…..  The fact that this IOD is going to become the dominant mode of tropical variability is pretty astonishing! Get ready for the possibility of some Real Arctic Air in December…..


68 degrees for the 18th of November?….Pretty amazing for Mammoth Lakes. Not a real heat wave but pretty mild for November. In looking at the Bishop Airport obs…so far 77. Official records were broken over the south-land today with highs in the low to mid 90s in some areas. Our storm system will drop quickly south tomorrow and actually track somewhat inland. Moisture will be provided by remnants of Raymond as well as off shore. The best area of deformation, (Surface Convergence) seems to be over Northern Mono and Eastern Alpine counties. Areas just east of the CA border may get up to a foot of snow in some of the mountains. Here in Southern Mono, somewhere between 2 to 5 inches seems reasonable. (Light Amounts) Areas east of Mammoth may do pretty well. Crowley Lake, Toms Place and Sherwin Summit may have some surprises….

This is not your usual Fall/Winter Weather system with a cold front. It is an area of Low Pressure that develops and spins up as it drops down or just east of the west coast, combining some moisture from a cut off low off Baja along with some of its own from off shore. It is small, but packs some real cold with it.  Highs in Mammoth on Wednesday will be in the low to mid 30s…..Some 30 degrees of cooling expected.  The storm clouds will retreat Thursday night leaving a fair dry weekend. The next system looks drier next week and the following one toward the end of the month may be colder yet and showery….

The Dweebs do not see any wet systems until we get into the month of December, where according to the longer range Euro, may bring some real snow!!

PS, the colder temperatures will really enhance the snow making efforts on Mammoth Mountain. I expect the snow making crews to be able to make a lot of snow and open many more ski and boarding runs over the next week.


Dr Howard and the Dweebs……………….:-)