Archive for November, 2011

Offshore Weather System Brings Up to 5 inches of New on Mammoth Mt……Big Change in Pattern Coming Next Weekend as MJO/ Heads for Phase Space 1

Nice little system Friday with brought a few inches of snow to the town and up to 5 inches on Mammoth Mt reported. The remains of the upper low is now headed for San Diego at the moment and is expected to bring some pretty heavy showers later today.  As the upper system heads east tomorrow, a dryer NW flow will develop and cloudiness will diminish. More sunshine is expected Sunday into Monday. 500mb heights will rise early next week and so with temps.  Expect fair/dry weather Monday through Wednesday with highs in the 45 to 50 degree range.

As has been advertised the past week here at Mammothweather….the MJO will be moving into a more favorable position by next weekend. Highlighted by the GWO, the GSDM is forecasting Stage 1 by next weekend. The global relative AAM anomaly becomes negative as eastern upper level wind anomalies that extend from the Eastern Hemisphere tropics to the Western Hemisphere mid-latitudes. This results in a retracted pacific ocean jet stream. This is like mother nature taking her foot off the gas peddle where then the upper jet then retracts. Negitive frictional torque>Negative Mountain Torque then eventually northern momentum transport across 35north shown by the GWO.

A full latitude upper Trof is expectred to develop by the 17th/18th over the West Coast according to both ECMWF and the GFS. Considering the support of the GSDM and MJO…..the Dweebs regard this as a high confidence outlook even a full week away……  Additionally, the PNA is now forcasted to become negitive. Western Trof/Eastern Ridge….La Nina Style……Winter is setting in……….

 

Dr Howard and the Dweebs………………………:-)

 

 

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Reference Glossary of Weather Terms
Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.

Little in the Way for Snowfall is Expected this Weekend as Closed Upper Low Heads Southeast well off shore…….MJO and GDSM Favor Stormy Weather Beginning Next Weekend Into Possibly Thanksgiving…..

Friday Am:

NMC/HPC Update Shows up to 4 inches of new snow over the crest with 1 to 2 in town by Saturday AM….with heaviest rain throughout San Diego County south. Coastal Sections of LA and Orange County under 1/2 inch.

Just a brief update.

Closed upper low is moving SE off shore and will effect mainly coastal section of Ca and especially Extreme Southern Ca. However, it is questionable how far inland the precip will get. Expect anywhere from 4 inches over the Crest to an inch or two in town Mammoth.

Next week looks pretty dry through mid week with near seasonal temps.

More importantly, using the MJO phase space and the GSDM model/GWO, it is evident that the far west will become increasingly under the gun for major storminess beginning about next weekend and may continue into the Holiday. 

The GWO “The Global Wind Oscillation” is expected to shift into Phase 1 by the next weekend.

From Global Weather Systems.com

Stage 1 (La-Nina like) – the global relative AAM anomaly is negative. The negative anomaly is primarily due to easterly upper level wind anomalies that extend from the Eastern Hemisphere tropics to the Western Hemisphere mid-latitudes. A retracted Pacific Ocean jet stream is a key feature in the total field.  Troughs are probable across the “western USA” with a ridge over the southeast.  High impact weather is favored across the Plains. The Signature is the reverse phase of the PNA teleconnection. So the odds are tilted toward a cold and stormy pattern for the Sierra with a Western Trof/Southeastern states ridge. And…..if there is an Arctic cold air source, Cold dry powder for the Sierra is possible.

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml

http://www.esrl.noaa.gov/psd/map/images/gcm/gwo_40d.gif

PS. The ECMWF is picking up on the change nicely…….

Remember…according to Ed Berry, the long range global models do not incorporate the effects of tropical forcing beyond 5 to 7 days.

ECMWF:  http://www.ecmwf.int/products/forecasts/d/charts/medium/eps/ensm/essential%21Geopotential%2520at%2520500hPa%21North%2520America%2124%21pop%21od%21enfo%21plot_ensm_essential%212010052412%21%21/

 

PS. For those of you that really want to get into the lastest cutting edge longer range forecasting that will improve your odds during week 2 and beyond, go to the following link:  http://www.globalweathersystems.com/Climatology/GWO.htm

 

Understanding the two systems, the MJO and the GSDM, and how they excite each other, is key to better week two and three sub-seasonal forecasting.

 

More Later……………………………..:-=)

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Reference Glossary of Weather Terms
Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.

Overall Pattern Looks Dry for Mammoth with Little Snowfall East of the Crest for Friday/Night……….

Overall….this pattern for Mammoth is a lot to do about nothing…..  The upper flow is strongly split out in the eastern pacific and the next system will spread its wrath upon the folks in So-Cal like the last one. Only this time this storm looks wetter for them.  Yea this is a La Nina winter.  However, as you can see, there is lots that happen in a winter like this. The MJO is still active and will be moving into a position more favorable for our area later next week.

For the time being…..The global models for Mammoth show a nice few days ahead, followed by mainly a coastal storm Friday into Friday night that will spread heavy rain over the central coast…then south to San Diego. However, very light snowfall is expected along the Eastern Slopes of the Sierra and for Mammoth as well.  At this time I am not looking for much more then a few inches here at most. Southern Ca will get clobbered along the coastal plain.

The next upstream system for Sunday is an inside slider type storm so expect some wind and maybe some flurries, maybe not. Otherwise it looks pretty dry for the weekend at this time.   Check back later… This is a changing situation as the models having a hard time with the weekend forecast..

 

Dr Howard and the Dweebs………………………:-)

————————————————-
Reference Glossary of Weather Terms
Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.