Archive for November, 2016

The current episode of anomalous warmth will peak over Eastern CA the next few days and hold through the weekend…..RIMM signel still very strong for pattern change later next week……

Quick Update this Voting Day Tuesday to say that the RIMM phase space is still a go for retrogression of the long wave features later this week into next week.  There will be no sensible weather changes this week. However, next week will become cooler by mid-week with an increase in wind and high clouds. High temperatures will warm to the low 60s today and hold there for several days. A little cooling is possible over the weekend but not much.  Nights will continue in the 30s at 8000 feet. There will be little in the way of wind.

The details in the structure of the wavelength across the pacific or how strong the amplification will become toward the end of next week is not known yet. Odds are that it will turn colder than normal, windy at times with the possibility of precipitation by weeks end. The MJO signal when used is only a tool for a change in the pattern over the western hemisphere that would affect any given area over the far west. However, it does not tell you how much snow you will get if any, or how cold it will become.  That information is in the future guidance of the global models with good confidence within 7 days of any particular time frame. This weekend represents the end of week two and the beginning of week 3 when RIMM Phase Space showed a strengthening signal east of the western pacific then eastward to the central pacific a week ago last Monday. Today’s NCEP briefing should shed light on what the signal really is as supported by other induces. I will update this Thursday via my weather letter 1st, then publicly this weekend via the Dweeb Report. As a comment, we all want tons of snow for various reasons. However, as of this time, no one has witnessed a late Fall 2016 winter like pattern yet. The precipitation events of last October and associated pattern are a lot different than the pattern that will be developing late next week and into the end of November. The Dweebs sincerely hope that when the pattern or structure sets up, that it will be a wet one for California.  Worst care scenario is that it turns cold and Mammoth Mt makes a lot of snow! 

 

Dr Howard and the Dweebs………………………:-)

 

MJO into Phase Space 6 then 7…Some high temperature records possibe for the Golden State…..Watch for big change in the pattern about the end of 3rd Week of November…

There is some amazing amplification taking place in the MJO RIMM. Today, as has been the case the past week the MJO phase space has been going crazy!  Take a Look!   http://www.cpc.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ncpe.shtml  That my friends spells real change!  It is a longer period western pacific tropical signal that has a pretty good linear relationship to our weather here in the Central Sierra, during the colder time of the year (Nov-March).  The MJO phase space by most global models gives you a look into the future…beyond the global models week 1 and 2. They are helpful in determining what weeks 3 and 4 might be like.  In this case…That a big change is coming the end of 3rd week of November through the end of the month. What kind of change? The MJO temperature composites indicate it will gradually turn colder over the far west beginning the latter part of the 3rd week of November into the end of the month, with increasing odds of snowfall in the Central Sierra week 4 or the period after the 21st through the end of the month.  Remember, this is a long-range outlook and not a detailed forecast like what the GFS or ECMWF guidance would show you. So the details are forth-coming but the change to cold is real!  For those that have subscribed to my by weekly letter, thank you.  I will have some special lead information that will be posted their in the letter and then on the Dweeb blog at a later date/time.

 

In the meantime…..its going to be Bikini weather along the coast for at least a week…..And warm with low 60s in Mammoth and possible low 80s for the Owens Valley in the not to distant future.

 

Dr Howard and the Dweebs…………………………:-)

 

October Record Rainfall to be followed by a Dubious November….some interesting developments through….

Its November 1st, and the Dweebs are beginning to look at the hemispheric weather pattern more seriously. I get that NOAA’s winter outlook shows no biases one way or another for Central CA and for good reasons. We are pretty much ENSO neutral with only a weak bias to La Nina.  In looking at the last couple of days ONI, you would think that we would be heading back toward ENSO neutral with weaker trades. However, this morning, numbers have become positive again and hopefully will increase further.  Some teleconnections are pretty interesting with an anomalous amount of snow piling up over Northern Asia. The feed back into northern hemisphere weather is very significant on a climate scale. Large heat sinks like that can feed back to cold deep Polar Vortexes in that region that can set up down stream patterns that will influence weather patterns going forward into the end of the year.  Additionally, the QBO cycle which has been in it positive phase for some 15 month is getting old and will most likely flip during the up coming winter. The other important teleconnection is the Pacific Decadal Oscillation which dramatically weakened in August and September. The surge of cool water extending east across the mid latitude’s between Asia and the central pacific suggests that the PDO is getting ready to strengthen again in the positive mode. This forces warmer then normal water along the pacific west coast and spreads it north and south. The other feature worth commenting on is the Solar minimum which we are rapidly heading into. The Sun has been flatlining more often than not the past year.

 

The short and medium range forecasts are pretty much dry for Mammoth Lakes except for the slight chance of some light snow/showers Sunday. Temperatures will warm up and become more seasonal later this week before cooling again late in the weekend. High temps will be mostly in the 50s this week and with temperature inversions mid week, lows in the 20s and 30s can be expected.

Looking at this mornings GFS and ECMWF, the models show very quiet weather conditions for the Central Sierra the next two weeks.  The Climate Forecast system as well as other longer range models show quiet weather the next several weeks and some for the next few months. I Look at those climate models un-enthusiastically.

 

Today I am very interested in what the MJO phase space charts are showing; A major “Highly amplified incursion into phase spaces 6-7-8 and 1.

  1. Precipitation relevance to phase space;  http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/Composites/Precipitation/NDJ/combined_image.png
  2. Temperature relevance to phase space; http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/Composites/Temperature/OND/combined_image.png

So this is what I am looking at now for the month of November. (subject to change)

MJO

The three global models of choice today are showing a weak MJO single for this week. (Week 1)  However, emerging in week 2, is a strong signal into phase space 6 propagating over time to phases 7, 8 and then 1.

If this signal is real, then the global models will adjust next week to become more highly amplified. Additionally, and again if the signal is real, we would expect the NAO to become strongly negative with a lot of high latitude blocking expected down the road. A big question will be, will the -NAO become west based or east based.  What this amounts to is where the cold is going to go, West or East. Best guess, “if the MJO signal is real”, stronger ridging over the far west weeks two and into three with cold in the east then retrogression spreads the cold west weeks 3 into week 4.   So the cold stormy weather would return during week 3 then into the end of the month.

 

The Dweeber…………………..:-)