Storm system with two parts to slow down the next 5 days with first oppertunity of light snowfall Saturday/Night…..More significant precipitation expected early next week……
Wednesday November 26, 2014
Posted at 9:42 am by Howard
Delay…..Delay…Delay…. That is what the models are doing with the large trough that will affect our area mainly Monday through Wednesday AM….
Here is the latest……..
The models are slowing this storm down!
1. Both GFS and ECMWF are both slower now than yesterday. They are even slower on this mornings 12z Wednesday run VS last nights 18Z run by 6 hours.
2. Over the next few days a “Long Wave Trof will carve out over the eastern pacific with two significant short waves.
3. The upper flow sets up SW by Friday night. So it will be breezy Friday night and windy over the upper elevations.
4. The main upper low has two significant short waves. The 1st one will more through the Eastern Sierra Sunday at 18Z (10:00AM) and the other 18Z Wednesday. Remember most of the storminess with a pattern like this, is prior to the passage of the trofs axis. So expect most of the precip with the first short wave, Saturday/night into Mid Morning Sunday. However the wave is shallow meaning it is not very amplified. This may allow light precipitation to continue into Sunday. Amounts at this time look to be in the 3 to 6 inches range by Mid day Sunday at 9000 feet. If the flow continues dirty, more could add up Sunday for a while.
4. We “short wave” ridge up Sunday night into 10:00AM Monday. That looks to be a dry period.
5. Big Picture…….What is happening is that another short wave coming down over the North Pacific Ridge which is over the Alaskan Aleutians Islands on Saturday, will dive into the long wave trof, position well off shore, both energizing it and causing it to retrograde west. This will slow the forward motion of the system by actually causing it to wobble west first before it progresses east early next week. This is a major storm…..make no mistake about it. It has the capacity to dump a good 2 to 3 feet or more, over Mammoth Mountain by Wednesday AM.
As a side note: for you folks in Southern California, the associated upper polar jet is progged to become confluent with a subtropical jet that initially develops south of Hawaii. The two upper jets are confluent for quiet a while Monday, well into Tuesday. This could be very significant for heavy rainfall for coastal mountain communities in Southern CA where there has been fires the past few years…..Glendora foothills etc. Make sure you folks stay tuned to local weather forecasts from the NWS.
If you have not mudslide prepped your residence yet for the winter rains this year, it would be a good idea to finalize things by this weekend. 7 Day QPF from HPC last night forecasts, showed over 4 inches of rainfall over the next 7 days for coastal Southern CA.
A lot has to do with the phasing of a typhoon over the western pacific later next week. The 12Z GFS shows it destructively phasing with the westerlies which would cause the upper EAJ to zonal out the upper flow, there by rebuilding the upper ridge over the west coast. However, it is certainly too soon to know for sure as the phasing is well over a week away….
The Dweebs will be with Family this holiday…and so the next update will be Monday the 1st.
I wish you all out there a Happy Thanksgiving……Gobble Gobble!
Dr Howard and the Dweebs……………………………:-)