Archive for April, 2015

After a Chilly Trof Passage this morning the Weather will Remain cool for a few days before rapid warming develops Friday into the weekend….Another System lurking for Next Week!

Cold Windy Weather, typical for April developed overnight with a few snow showers early this morning. Although some locals called it Hail….It was actually Snow Pellets. A type of precipitation common in the Spring.  Strong gusty winds both preceded the upper trof and followed it.  Winds diminished this afternoon in town. Temperatures today were in the 40s and I expect them to remain about the same or a little warmer on Wednesday.

A warming trend will begin Thursday with more rapid warming expected Friday. For the weekend, expect afternoon convection both Saturday and Sunday leading to a slight chance of late afternoon and early evening showers.   Highs over the weekend will be in the low 60s with lows at night mostly in the 20s. Next chance of a weather system and cool down will be about the middle of next week.  More unsettled weather is expected the second half of April as well as the early part of May.

 

 

And now Ladies and Gentleman “The EL Nino Hype Begins” !  😉

 

https://robertscribbler.wordpress.com/2015/04/09/onrush-of-second-monster-kelvin-wave-raises-specter-of-2015-super-el-nino/

Warmer Weekend on Tap with a few showers Sunday PM…Then windy and cooler by Late Monday Pm into Tuesday….Thereafter a warm up into the following weekend….

Not much going on weather-wise the next few days. However ,Skiing and Boarding were reportedly very good on the upper slopes yesterday with folks I spoke with late afternoon Friday….

High pressure aloft building in today will set the stage for warmer weather today though Monday PM, then a cold front is expected to move early Tuesday bringing mostly wind and cooling….That will be followed by warmer weather Thursday into the following weekend. I still see the chance for more cooler periods in April with even some snow showers well out into the future. However, no major storms in the extended outlooks.

Climate/Kelvin Wave action

Although the non winter of 2014/15 is drawing to a close, there are very exciting curiosities that are currently on going underneath the Equatorial Pacific. Especially underneath the eastern half, east of the dateline. As mentioned in several previous posts, there is a Kelvin Wave that is currently surfacing over the Eastern EQ pacific. Last year this time there was a lot of reference to the “KW” that was expected to jump-start El Nino, with a lot of Hype to that possibility over the Spring, Summer and Fall. We know now that is not a guarantee of A major warm event as there are other teleconnections that need to happen to keep the ball rolling….    The KW that developed earlier this year looks a bit stronger than last Springs Wave;

See Comparison’s below:

2014-    http://www.bom.gov.au/archive/oceanography/ocean_anals/IDYOC001/IDYOC001.201404.gif

2015-    http://www.bom.gov.au/archive/oceanography/ocean_anals/IDYOC001/IDYOC001.201504.gif

Comparing the two structures in the examples in the above links, note the top frames “isotherms”. They appear to be very similar. However this years KW is actually a bit warmer over all if you look at the Isotherms in comparison. The third structure over the bottom is about 2 weeks apart in time, so I will update the next month.  That bottom frame references the Anomaly, and so needs to be the same in time frame.

The Dweebs believe that the latest and may I add strongest in sigma MJO in that phase space, that peaked early in March, most likely initiated strong cyclones on both sides of the equator. They possibly initiated an anomalous period of westerlies along the EQ, west of the Dateline. The prolonged time frame was about 10 days.

Major Kelvin Waves and frequent, strong Westerly Wind Bursts along the Equator over the Western Pacific are the anomalies that “enhance the odds” of a stronger warm ENSO event.

The Current KW that is now surfacing has Isotherms under the sea surface at 150M warmer than  +6C. See:  http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/anim/wkxzteq_anm.gif       Note:   An update to this will be coming over the next few days and so check it again soon….  SSTA’s are rapidly warming over the Nino 1 and 2 region, and the deeper anomalous warm isotherms will rise into regions 3 to 4 eventually.

 

Lots to follow the rest of the Spring and Summer over the Equatorial Pacific….

 

Dr Howard and the Dweebs……………………………………….:-)

Mammoth Mt Receives 18 to 24 inches from the biggest cold storm of 2015!…and over a foot at the Village at Mammoth…..Beautiful weekend for skiing shaping up……The Next Storm about the following Tuesday!

Thursday 6:15 PM

Warming trend in play with lots of high clouds due to the splitting system off shore.  No real changes to the forecast other than to add some CU over the Sierra early in the weekend. There is a chance of snow showers Tuesday/Ngt.. No big deal though…The rest of next week looks fair.

At this point I do not see any major storminess in our future. Both 6 to 10 and 8 to 14 day outlooks are dry.  Beyond week 2 climate wise, it is getting pretty late in the season for a major storm….  The Dweebs will keep the faith for one or two more cold systems.  We have had decent snow producers in May historically, but they are not all that common, especially with all that anomalously warm Eastern Pacific Water. (+PDO)

 

The Dweeber……………………..:-)

 

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As the cold pool shifts east today and the clean up finishes up this afternoon, the Dweebs must remember that the QPF for our area in the sierra is often under estimated when;

1. You have the upper flow natural to the sierra.

2. A strong cold front with a lots of UVM ahead of it.

3. Good upper divergence over the area

4. Most of all….A cold pool capable of heavy convective showers following the front.  The heavy convective showers last night brought another .5 inches of H2O to the mountain and another 6 inches of snow. This was more than earlier forecasted by all forecasters early Tuesday AM for our area.  I will say that I did update between 2PM and 3 PM yesterday afternoon after looking at the latest RHHH “Rapid refresh model” when it was evident that heavy convective showers were headed for the Central Sierra during the night. We received 1 to 2 inch per hour snowfalls.

 

Forecast….

Partly cloudy during the afternoons the next few days with a warming trend into the weekend. Expect about 8 degree of warming over the next few days through Friday and then upper 50s over the weekend.

 

Longer range:

I personally like the next system better than some of the other Dweebs….    As although the models have the next system to be more of a northwest slider, to me it looks like it will have the potential to dig further west with time as the upper jet has a good temperature gradient as it digs south..  This is not to say that it is impossible for the current NW slider to continue into the shorter range. I am just beginning to see some bias more to the west.  Stay tuned….as this may end of being another decent April Snow Producer about Tuesday next week…..

 

El Nino:  It should be acknowledged that most climate scientist’s at this time are doing a great job of not hyping the developing El Nino over the EQ pacific. They were badly burned last year with the Modoki that set up leading to a winter similar to 1977.  This Dweeb does not want to hype it as well. However, there are some interesting observations that one should consider. There are some differences between where we are this year at this time as compared to last year at this time when it comes to the temps over the NINO basin.  Last year, there was a rather large Kelvin wave that surfaced over the eastern pacific. This year at this time we have the same scenario. IE Another very warm KV surfacing in the same area.  However, the big difference this year is that there are antecedent conditions that are much warmer already in the Nino Basin. The KV now surfacing will only add to that heat in the basin.  The average SSTA for the 3.4 region of all models is now “Forecasted to be 1.5C by *August.  That is within the moderate El Nino threshold. However, August is not December, January and February. A lot can happen 5 months later…. Nevertheless, the odds of reaching the moderate threshold temperature wise is very possible now by August.   Remember that for an El Nino to be classified as moderate,  it has to remain at about that threshold in the Nino 3.4 region for at least 3 months….

Some additional thoughts…

The record setting  MJO last month was able to move a lot of warm water eastward toward the EP.  The MJO space space shows it to reemerge out over the Indian Ocean. However, the signal may be related to low frequency noise due to either KV or RW action…  The Dweebs are questioning whether the MJO will strengthen enough to excite twin cyclones again, pushing more warm water eastward toward the eastern pacific later this month and into May…..thus bringing further warming to the Nino Basin.

The current KV now rising is amazing warm!

 

* http://www.bom.gov.au/climate/ahead/model-summary.shtml#tabs=Pacific-Ocean