Saturday 1:00PM

We received a nice break from smoke from the Rough Fire yesterday as a moderate SW flow developed.  Today’s upper flow suggests a light NW flow aloft,  keeping much of the smoke suppressed to our south.  By late tonight the NW flow will weaken and Smoke from the Rough Fire will probably move north again into Southern Mono County. According to the models, increasing throughout the day Sunday and into Monday…..  The Fire is 25% contained with over 86,000 acres burned.

For a better idea on smoke forecasts for our region check out the link here:  http://www.airfire.org/data/bluesky-daily/

And here:  http://viewer.smoke.airfire.org/run/standard/CANSAC-2km/2015090500/

 

Please remember that the models used in forecasting smoke are experimental, and not always accurate.

 

The main Vort center in the Upper Trof is now into Northern CA. Winds will pick up today and continue into early evening associated with the Upper Jet that will be rounding the base and carrying the upper system east. I expect Saturday to be the coolest day with some warming coming back into Mammoth Sunday into Labor Day.   High temps will be in the low 60s today and Saturday with some freezing temps Sunday AM.

 

Here is a very good and timely link to an article from Daniel Swain, A PHD candidate from Stanford University on the current Status of El Nino and answers question regarding some of the questions of the Big Blob or anomalous warm water, both in the Gulf of AK and off the Pacific Northwest coast.

http://www.weatherwest.com/archives/category/uncategorized

 

Not mentioned in this article is “The forecast” from the CFS v2 of the Warm Blob cooling as we going through the winter, possibly as a by-product of the same things that created it in the beginning.

What is so important about the blob of warmth in the Gulf?

Well…. in the beginning of the Fall, not much. Weather systems tend to ignore it as the North American continent is still the main heat source and thus ocean temps anomalous or not have less influence on weather systems. However, as the sun gets lower in the sky and the CONUS cools, Ocean temps (SST’S) begin to have an effect by steering storms around these large masses of extra warmth such as the one in the Gulf of AK. Thus…an area of “blocking” can “Dam Up” the cold over Central Canada and deliver it south over the nations mid section and east.

In the Case of El Nino…..as the Asian Jet strengthens later in the Fall and especially January and February, the extra warmth and convection over the Nino 3 and 3.4 region clashes with a more southerly upper Jet that is common for that time of the year. The upper jet with a southern split over the east central pacific drives both moisture and energy east along the southern tier states and helps to carry Arctic Air out off the Atlantic coast. An excessive wave length occurs by the PV being displaced further to the east….and a progressive march of short waves are allowed to progress east along 30N to 37 North where they lift NE over the eastern sections of the CONUS.

The stronger or warmer the SSTA’s are,  the stronger the southern branch and subtropical jet is. As a result, a stronger signal for a wet CA winter….

So whether or not this fall is wet and it “may or may not be”…..Eventually a strong Southern Branch of the jet will develop, no later than January and CA will get pounded….

 

As a side note…..during strong El Nino’s the southern sierra gets a lot of precipitation. I hope that the ongoing fires have not destroyed critical watershed as that could be another potential problem as well.

 

Dr Howard and the Dweebs………………….:-)