Another Active 2nd half of the week is expected with the potential of more heavy rain Thursday Night into Friday….October rainfall records look to be in jeopardy….
Monday October 24, 2016
Posted at 10:00 am by Howard
The front left exit region of the subtropical jet is creating the lift this morning to produce some light rainfall in the Town of Mammoth. Once this wave passes we will have lots of clouds the next couple of days but dry weather. A long wave trof has taken up residence over the Eastern Pacific. However, too far west for cold enough air to bring snowfall to the Town of Mammoth. Heights remain in the low 570s DM at 500MB, so we are in the sweet spot for rain and tropical moisture but little in the way of snowfall at the 7000 to 8000 foot level. This large-scale adjustment wave will continue to send several shot of energy into the west coast over the next 6 to 10 days affecting the central sierra periodically. The most significant development is hurricane Seymour off the coast of Central Mexico. This moist system will be moving over colder waters soon…thereby dissipating and releasing its moisture into the surrounding area. With the long wave located at 135 west and a rather sharp short wave progged Thursday AM, no doubt that there will be some heavy rainfall headed for the Sierra Thursday afternoon into Friday AM. The PWAT from that fetch is forecasted to be as high as 2.00 inches Thursday AM just off the central coast. Rainfall amounts may tally similar amounts that occurred weekend before last, tying all time October rainfall records for the Central and Northern Sierra.
As far as snowfall, most of it will be above 9500 to 10,000 feet again. At the moment, the OIP looks to be Thursday night into Friday AM.
+SSTA’s are still warmest in the North Pacific. If they remain their, that would lend bias to some mighty cold weather later in December and January. As mentioned in a past discussion, this is a winter that will be difficult to forecast as the climate models have not done a good job so far. I would not put .02 cents on any long-range forecast at this time. As an example Scripps forecasted a “strong La Nina” last Summer and that goes against most climate models now. The PDO as become neutral the past 2 months and there is only speculation on what it will do this winter. If the Warm Blob backs into the NE Gulf of AK again, there goes our winter. If it remains weak, with anomalous SSTA warmth continuing over the north pacific, that would be more interesting for a normal to wetter than normal winter. The Climate models can forecast all they want but if they do not pan out, they are worthless. Best to stick to the week one and week 2 forecasts and track the MJO for highlighted weather events this winter….
Note; the Dweebs will take a hard look at things later in November to see if there is more consistency in the climate models and at the least, the forecast of the PDO and ENSO.