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Revisted this weather snow link I saved a few years ago and features have obviously been enhanced.


Found two animations rather interesting.   A good way to review how the Tahoe ski season has gone to date.  Outside notes on using the maps, the following is probably only going to be of interest to we Californians however other regions can be selected in like manner.


Mouse click the Season field in the Snow Precipitation map that will open a small pop up window which will immediately start running an animation at 200ms per day that is too fast to make sense of.  Each day a reading seems to be at 06Z.  For instance if the date is Oct 12th 06Z. Zulu time on the International Date Line is 8 hours ahead thus it is actually 10pm Oct 11 Pacific Standard Time.


Mouse select the Larger field which will zoom in on the window.  Use the scroll bars to enlarge the window. 


When the date reaches a January date mouse select the Stop button.


Change the Speed in ms: field to 1000 .  That will slow the day switching to 1 second. 


Select Start and after a few changes the date will return to the initial date of October 1.


Select Stop and notice how the button toggles.  Each time a date shows some snow select that button to look at the snow pattern then resume by reselecting.  If you miss a date you want to repeat, select Stop, remove a 0 in the Speed in ms for 100, then allow the animation to rapidly loop back to where you were, key Stop, and add the 0 back for 1000.


The first significant snow is on Oct 12 at highest southern High Sierra crest areas and nothing about Tahoe. The values are not snow depths but rather liquid water equivalents where 1 inch is vaguely 10 inches of average snow. It does not include any precipitation that falls as liquid. Select Start again then immediately Stop it.  Notice how the storm lasted two days with the second day greater precipitation.  


The next storm dropped considerable precipitation on Oct 23 across the whole range.  Notice all the brown areas of 2 to 3 inches.  Of course some of those areas received more than 3 inches that would be 30 inches of snow.  The next day Oct 24 was focused from the Central Sierra north with the snow levels lower causing a broader zone of snow.  Such lowering snow levels are typical with Sierra winter storms.  Likewise the third day Oct 25 was centered even further north.  Oct 26 was just a light dusting, and Oct 27 no precipitation.  Thus a 5 day storm series.


A light dusting visited Nov 2, then a good storm began Nov 9.  Notice how Nov 10 the main snow shifted to the southern areas.  Nov 11 was winding down with Nov 12 dry again.  A 4 day storm series.


Next small storm began in the southern Sierra Nov 16, got going from Tahoe South on the 17th, and peaked on the 18th thru 19th, waning on the 20th. A 5 day storm series.  Got my first day in skiing after those storms.


A one day dusting occurred Nov 22 then a large storm arrived Nov 29, the week after Thanksgiving, then waned a day, with the main event on Dec 1, then waned a day, with another big storm Dec 3.  Notice all the broad brown 2 to 3 inch color.   Notice how the color abruptly goes to no snow at all to the west?   This was that 5 day series of high snow levels that did wonders for Mount Rose, Kirkwood, and Mammoth, but was unkind to most other Tahoe resorts.  I got my second day in skiing at Kirkwood Dec 8.


Some lingering dustings followed and by Dec 9 was dry.  Then on Dec 13 a major low elevation  winter storm across the whole range promised good Christmas skiing.  Notice on Dec 14 snows to the south even on the Tehachipi's?  Low level snow lingered each day then on Dec 18 and 19 another major cold storm. Before Christmas, Dec 20 and 21 were dry.  Thus 6 days of at least some snow.


Then another bit storm in the northern Sierra Dec 22 peaked on Dec 23 and Dec 24 across the whole range providing the bulk of the excellent snow we are now skiing.  I skied fresh powder at Kirkwood on that Christmas Eve.  Another dump came in Dec 26 and 27 lingering a coupled days with snow showers then another storm Dec 30 before New Years which was dry and was another powder day I visited Kirkwood on. Thus a 10 day storm series.


Finally the recent storm on Jan 7 which was mainly a Southern Sierra event with Mammoth Mtn benefiting.


The other map I found interest was to perform a similar animation on the Snow Depth map.  Fascinating how the snow melts back from the fringe lower elevation areas after each storm passes.   For those living in other USA ski regions of course the same might be performed.