Upper High centered over Northern California today will remain in the Vicinity through Monday. Sunny skies, Clear Nights along with light winds are expected to continue….Cooler breezy weather to develop by Tuesday night into Wednesday with the chance of showers……Time to Spring Forward Saturday Night!
Friday March 6, 2015
Posted at 9:59 am by Howard
If you caught this mornings Sat Map, the big closed low NNE of the Big Island has tapped a plume of moisture from the ITCZ…. An Atmospheric River (AR) has been created…. What a waist, as it’s too bad it is not directed into CA! SEE: http://www.ospo.noaa.gov/Products/bTPW/index.html
Discounting the short and medium range where there is still a slight chance of showers in the forecast the middle of next week; It is not surprising this afternoon by the looks and recent trends of the ensembles of the ECMWF and GFS, that the CPC has gone warmer and drier than normal for the next 14 days. They tell a story that is getting older by the year…..
PS Don’t forget to spring forward an hour Saturday Night before retiring for the evening or it will be later then you think Sunday….
Looking at the latest guidance this morning not much has changed forecast wise for the next 5 days except to adjust up the temps over the lower elevations of Eastern CA/Owens Valley the early to mid part of next week
The outlook still shows cooler cloudier weather with the chance of showers by the middle of next week as the present upper high gets dampened and shoved east by the westerlies. In that the upper jet remains well north of Mammoth, the air mass will be mild mid-week with higher snow levels for any shower activity. Model “trends” appear to be stronger now with the upper ridge over CA that following weekend. This occurs as shown by todays 12Z Friday run of the new higher res GFS T1534. Its deterministic run shows today, a trapped closed upper low near 155west. and a closed upper high centered over CA at the moment. Upper heights weaken to the north over the GO/AK the next few days and the closed low progresses east. As lower Upper heights developed over the GOAK the upper jet strengthen and both flatted the west coast ridge and pushes parts of east next Wednesday. This allows cooler wetter weather to develop over Northern CA northward, giving Mammoth mostly wind, cooling and a chance of orographic showers. There appears to be two decisively different systems/streams out over the mid pacific later next week. The southern branch seems to have the greatest -(height anomaly).
The prind point here is that if the current GFS T1534 is correct, the deepening of the southern system next Thursday near 150w to 140w will actually strengthen the upper ridge over the far west, wave length wise, and delay a significant system that next weekend of the 14th-16th, (if the new model run and trends continue).
Of interest is what is following the slow moving mid latitude low by the 16th. It looks like that there is an extension of the East Asian Jet moving across the pacific. That may push the remains of the old low, into CA, beyond the 16th. It will be interesting to see how far east that upper EAJ jet gets. That following week the models show that upper jet has 200knots in its belly…..moving across the date line…..Hope it continues to be progressive…..
Again…as mentioned a few days ago…the idea of an atmospheric river is off the table for Central CA until further notice…..