The CPC this AM gave a nice discussion in regards to the MJO, the Current Kelvin Wave and ENSO:

Here are the important points of interest:

1. A strong kelvin wave is currently out ahead of the position of the MJO’s convective envelope and interacting with the EL Nino Base state. Enhanced tropical convection is occurring south and a bit west of Hawaii near the EQ.

2. MJO is destructively interfering with the ENSO base state, but that will soon change as the convective state shifts east.

3. The Nose of the KV is located about 125west and still adding heat to the Nino Basin.


1. The Convective state of the MJO will shift east to the eastern part of the Maritime continent with tropical storms forming their over the next 7 days. That area will shift east week 2, for the tropical longitudes between Central Micronesia and east to just beyond the Big Island of Hawaii. Expect tropical storms and typhoons to develop in that area during those times. IE north of the EQ moving west.

2. During the later part of week 2 and into week 3 (around the Fourth of July holiday or just beyond the Fourth,  the MJO will constructively interfere with the ENSO state over the Eastern Pacific for an enhanced state for Hurricane’s and tropical storms over the tropical Eastern Pacific, eventually leading to enhance the Southwest Monsoon  early the following week of July 4th. This may or may not effect CA as retrogression of the Long wave may send most of the Monsoon moisture further east.

Temperature’s continue about 10 degrees above normal for this time of year with highs over Mammoth in the Mid 80s. Nights will be most comfortable for those that sleep with the windows wide open…Screens included.  Some of the summertime bugs are now out but the Bats in the evening are busy getting a mouthful! 😉

I expect a bit warmer weather into the early weekend before Thunderstorms and airmass modification leads to cooler afternoon highs.  Wetter storms are possible Sunday into Tuesday next week, with the pattern lasting right into and through the 4th of July weekend!

The Details:  Tomorrow Thursday, the Continental Subtropical high redevelops over the desert southwest again, then bubbles up over Utah and NV. This feature will work in tandem with an upper low forming more from a “Coll” ….Thursday into Friday. The upper flow begins to be channeled up into CA from the subtropics.

Over time….The upper continental high becomes negative tilt with both moisture transport as well as upper divergence. They will work together to bring wetter storms into the Sierra, Sunday….through Wednesday.   Afternoon and evening thunderstorm’s will likely continue well into next week. High temps in Mammoth will occur earlier in the day next week due to more afternoon clouds, higher dew points and Scattered Thunderstorms.  Lows at night will be mostly in the 50s, next week.

Post July 4th:

The Western Hemispheric pattern goes into retrogression around the 4th of July.  The new 12Z June 24th deterministic EC retrogrades the upper high from the pacific NW out to about 140west. The EC ensemble”s do not make that much of it..  The GFS ensembles doesn’t do much with it either. In fact the GFS builds back the Continental high that week.  The ECMWF deterministic, tries to pull down an inside side slider over the Northern Rockies or Northern Great Basin.

With as strong as the Continental high is, I have serious doubts that it will affect California or most of NV.  But still…..The big question for the week following July 4th, deals with this possible retrogression and how the models will handle it.   Also what role if any, where all that subtropical moisture will go, as MJO modulates the southwest monsoon at that time.



As per past discussions,  The Dweebs are watching the location of the MJO’s convective state in blue as it moves from the Maritime Continent,  then into the western pacific.   Thereafter, it shifts east toward the dateline then Eastern Pacific, all in a 2 to 3 week period.


The core of the Blue is the area with the most intense OLR or the best convection.  That area, early next week, will create a large area of upper divergence over the tropical western pacific and increase chance of tropical storms and possible typhoons over the Western Pacific.  Eventually it will shift to the Eastern Pacific by the end of next week.

The enhanced convective state of the MJO over EL NINO creates “constructive interference” in the MJO signal. However, the term “Constructive” is what is most significant in the terminology, as the enhanced convection from El Nino combined with the upper divergent state of the MJO leads to a large area of very warm and saturated air mass over the eastern pacific tropics.   The Dweebs would expect the formation of tropical storms and hurricanes spun up from the ITCZ and eventually an enhanced monsoon to develop around or the week following the Fourth of July weekend.  The global models this morning showed a rather strong easterly wave tracking across MX.


Temperature forecast:          Tuesday       Wednesday      Thursday       Friday        Sat            Sunday       Monday

Mammoth Lakes:                   49/84              49/84              50/85          51/86       54/87          56/85          55/84

Bishop:                                   54/102           55/102        65/103         69/105     70/108          70/104       72/102