Thunderstorms to highlight the Forecast along with areas of locally heavy showers through Wednesday…Drying to begin Thursday with a fair, warm, dry weekend expected…..
Tuesday July 15, 2014
Posted at 9:15 am by Howard
Southeast flow and abundant moisture along with light winds will keep the thunderstorm threat high over Mono County both today and Wednesday. A vort center over Southern NV is stretched east west and will shift northwest into Southern Mono County later today and remain stationary through Wednesday Afternoon. Moisture and dynamics will increase through Wednesday afternoon. Thunderstorms are possible Today, Tonight and Wednesday. Locally heavy rain is possible as well. The National Weather Service has a flash flood watch out for Mono County Wednesday PM……However, late this afternoon and evening look to be quite active as well, especially for Southern Mono County.
Drying begins to work into our area Thursday with the threat of heavy rain beginning to diminish. Drier weather for Mammoth is expected Friday with most storms to our north and east with a fair dry weekend expected. Highs will be near 80 today then cooling to the mid 70s by Saturday as a trof of low pressure deepens south into the weekend. Expect moderate zephyr winds by Friday. More hot weather is expected to redevelop next week.
Dr Howard and the Dweebs…………………..:-)
Dry Weather is expected over the Eastern Sierra through Monday with a Warming trend through Sunday……Monsoonal Flow Resumes Tuesday with an increasing chance of Rainfall for Mono County…
Friday July 11, 2014
Posted at 9:45 am by Howard
After a couple nice days of rainfall the weather will be dry here in the high country with a strong warming trend Through Sunday. High Temps by Sunday and Monday will be in the upper range of the mid 80s with lows in the low 50s. South-East flow and dynamics will return Tuesday through Thursday next week along with Rain Showers and Thunderstorms.
Enjoy the Wine Fest…..Later today and Saturday…..Two of the best wineries will be attending from the Howell Mt appellation in the Napa area. “Saunter” and “Outpost Winery’s” are some of the best from that region!
This mornings guidance along with the water vapor loop shows a weak trof of low pressure off the CA Coast at 135W, ushering in a drier SW flow into California. With the drier air, comes a more stable air mass, more sunshine, rain free conditions and slightly warmer temps. The upper low will not come inland, but instead, lift north along the same longitude in response to increasing heights from the east over the weekend. The result will be that the continental high over our countries mid section will retrograde west over Nevada and California by Sunday. This westward shift will challenge the warmest temps so far this Summer here in the Eastern Sierra Sunday, and again Monday.
Next week the guidance suggests that the upper high will begin to weaken and a SE flow develops again out of the Desert Southwest. A Rich Moisture source is currently in place over NW Mexico. This in time will be drawn north into AZ then NW into Eastern CA Tuesday through Thursday. This South East flow is the Monsoon, (seasonal wind) which will be accompanied by a more dynamic, unstable air mass….And the possibility of additional rainfall for the Sierra.
If you remember, the Climate Forecast Systems forecast for the eastern sierra for July posted here in the Dweeb Report had indicated that precipitation for July would be in excess of 200% of Normal. Normal is probably about an inch of Rain for the month of July here in Mammoth. Yesterdays Rainfall tallied between .2 and .4 inches over the Town of Mammoth Lakes.
Another robust kelvin wave is located over the Maritime Continent and is progressing east along the Equator. In the front of this system is a down welling component that showing up, evidenced by the warming of the subsurface ocean waters between 160E and the Dateline. In my opinion, this looks like it will effectively re-energize the Nino Basin later this Summer and Fall. You can track this Kelvin Wave at the following link and watch its progress this Summer and Fall.
The latest advisory from the CPC indicates that there is a 70% chance of a Weak to Moderate by the end of the Summer. Furthermore, those odds increase to 80% by Fall. The Dweebs believe that a Weak to Moderate El Nino will have an affect on California’s weather pattern next winter and Spring.
The ONI index is used in the following study for determining El Ninos effect upon precipitation over California. This research has been a work in progress by Meteorologist Jan Null a current CCIM and past lead weather service forecaster in the Bay Area.
You can review his work here at this link: http://ggweather.com/enso2014/
Also since there is likely going to be a lot of rumors flying around the next 6 month about El NINO, I though it would be appropriate to include Jan Nulls List of Myths, some of which you may actually hear from someone this Summer or fall…
Have a great weekend
Current Episode of Moist SE flow to begin diminishing by Friday leading to a fair warm weekend……In the meantime, High Country Showers and Thunderstorms possible, shifting a bit east Thursday…Then Dry Friday through Sunday
Tuesday July 8, 2014
Posted at 10:52 am by Howard
There has been a nice moist SE flow pattern over the Sierra the past few days…however little in the way of a trigger for heavy rain until today…Today looks to be the best day for some substantial rain over Mono County….With POPs as high as a 60% Chance!
Scattered Thunderstorms will redevelop Wednesday…..However, without as big a trigger as today. Nevertheless, storms may form again and areas of heavy rain possible tomorrow. A weak trof of low pressure will begin to back the upper flow from the SSW Friday with even more SW flow Friday night into Saturday. The weekend looks fair and warm with highs returning to the low 80s by Sunday.
Outlook for next week:
The Subtropical upper high builds back into California by Sunday and remains the dominant feature next week. A combination of light flow aloft and daytime heating will result in the typical air mass thunderstorms with forcing mainly the typical high elevated heat source of the Sierra in addition to the usual surface convergence that is moves about on a diurnal bases. At this point, I do not see another Strong SE flow set up….that is not to say that one could not develop between today’s model runs and the end of the weeks runs for next week.
The latest numbers for the Nino 3.4 and 4 region are pretty anemic. The very strong Kelvin wave that moved across the pacific has run its course. This is at least, part of the system that created the very warm SSTA’s, South East from Pt. Conception to San Diego where sea surface temps are as high as 78 degrees off the San Diego Coast and positive SSTAs are also found south along the Baja Coast.
The latest weekly Nino data shows that during the time period of June 25th through July 2nd, all Nino regions of the Nino Basin have cooled with the exception of Nino Region #3. This was a direct result of the rear upwelling phase of the Kelvin Wave. As of late, a new but weaker Kelvin Wave is beginning to increase the sub surface temps and thus making an effort to renew the heat in the NINO basin over the next few months. The Down Welling phase in its nose is warming the subsurface heat content at longitudes of 160 East to 180 West.
At this Time…it is the opinion of the Dweebs that it is highly unlikely that we will have a “Super Nino”, one which SSTA’s are at, or above +2C in the Nino 3.4 region. However, even a weak El Nino (.05C) can bring a normal amount of Precipitation to Southern CA and a winter that is 80% to 90% of normal to the Central Sierra Crest. There are a lot of Split flow systems in a Weak El Nino and so coastal areas of Central and Northern CA can get a lot of rain while interior sections can get much less.
There is no real way to predict with much certainty what the winter will be like until the Early Fall, as by then, well have a better idea on how the Nino regions are doing heat wise as well as the other teleconnections that will be effecting the weather for the upcoming winter. One thing is known at this time….The PDO is positive and the QBO is negative which argues for another cold winter east of the Divide. The big question will be…Will the stronger than normal subtropical upper jet be strong enough to flush out the cold air from the Hudson Bay > east out over the Atlantic next winter…..
Dr Howard and the Dweebs…………………………….:-)