Saturday, December 10, 2011

Next Week Looks Interesting

It looks like another cyclone in the southern branch of the 500 mb westerlies will move across the Southwest during early to mid-week next week. See ECMWF 500 mb forecast above valid at 5 pm Tuesday afternoon. The NWS GFS 500 mb (from 00 UTC last evening) ensemble forecast average and spaghetti plot, valid at the same time, are shown below. The mean trough over the West is somewhat similar to the ECMWF; however, the most spread in the model forecasts (spaghetti plot at right) extends from the Great Lakes Region to all of the West coast - so, details and timing are different in the various members. All members tend toward a widespread precipitation event, with significant snows in the east-central mountains of Arizona. Will be interesting to observe how this next weather event evolves.

Interesting convection at about 10 degrees north. A very large convective system has been moving to the east across the Pacific (WV image above is from 13 UTC yesterday and image below is from 10 UTC this morning) and is now approaching 130 W. I won't attempt a guess at what exactly is forcing this event, ut comment most welcome. Note also the three, upper-tropospheric, waves strung out to the west of northern California. The eastern Pacific appears to be very "busy."

No comments:

Post a Comment