Friday October 28, 2016
Posted at 4:27 pm by Howard
Some nice precip totals so far. At the Village at Mammoth 2.13 inches of rain so far has fallen. 2.78 on Mammoth Mt.
The wet short wave has now passed into Nevada and improving weather is expected until Saturday night when a colder system arrives with Snow expected in town. Storm number 3 if you want to call it that is pretty whimpy. Only expecting a dusting Tuesday morning….
Tioga Pass did close this afternoon. It is not known if they will reopen again before they close for the season Saturday afternoon for the next storm… PS I hope it reopens as the Dweebs have to travel to Fresno Saturday….or it will be “Take the Long Way Home” Faav Supertramp.
The Dweebs do see another weak system Monday night and then a long long break before the next series of storms arrive….
Dr Howard and the Dweebs……………………:-)
Big Wet Storm in process with lots of rain Tonight and Friday…..Big PWAT Plume pointed at Mammoth…Snow in the Town of Mammoth Sunday/Night…
Thursday October 27, 2016
Posted at 5:56 pm by Howard
Storm 1. Just like I said….Models do not handle Subtropical moisture very well. Most of the models had the bulk of the precipitation further north of Mammoth but they have been back peddling south the past two days. 500MB 567DM upper low is west of Pt Conception with both subtropical and weak southern branch of the polar coupled well west of the coast. Seymour has been down graded to TS and is still pumping a lot of heat into the system thus doing the job of Jet stream enhancement. PWAT plume of 1.7 to nearly 2.00 off the South Central CA coast with the trajectory into the Central Sierra. This is +5 to +6 Sigma as far as the anomaly.Thunderstorms a good possibility over the southern and central San Joaquin Valley and into the sierra tonight.
No doubt the QPF Bull’s-eye is over the central sierra on this 1st storm. Get ready for some heavy rain later tonight and possible thunder. Heavy rain will occur after midnight tonight as well into Friday morning. Again this is not and I repeat not an AR event, no matter what the Colloquia’s want to say. This PW plume is wider than long. AR events are fairly narrow rivers of high PWAT that stretch thousands of miles usually West to East or SW to NE. This one is an inverted V. PWAT is not the only definition for an AR.
Storm 2. Sundays storm will drop 12 to 18 inches over the crest and possibly 4 to 7 in the Towns of Mammoth and June.
Storm #3 is minor with lights amounts. “Monday Night” (A trace to an inch)
October 2016 is on the threshold of record rainfall here in the Central Sierra.
Dr Howard and the Dweebs…………………………:-)
Height Rises to provide warmer days and a bit of a break in the wind later today and into Wednesday….Next short wave to tap Bonanza of subtropical moisture from north of ITZ and remains of Hurricane Seymour with potential for another rain event for the high country Thursday into Friday…….Cooler system to move in Late Saturday night with the chance of some snowfall to the Towns of Mammoth and June Sunday AM….
Tuesday October 25, 2016
Posted at 9:31 am by Howard
As the pattern evolves this week, the picture is becoming increasingly clear that another wet storm is in store for the Central and Northern Sierra for Thursday into Friday and a colder system late Saturday night into Sunday with Showers possible Monday. The first system has a big tropical/subtropical tap all the way down to north of the ITZ and no doubt has moisture from Hurricane Seymour. PWAT is forecasted at high as 1.50 to 2.00 inches along the coast of Central CA Thursday AM. A healthy subtropical jet of over 100 knots is associated with it. The freezing level is expected above 11,000 feet and so for the most part, this is going to be another rain event for Mammoth and the Eastern Sierra Thursday and Friday. The forecast models are now showing a colder system for Sunday morning that may bring snowfall into the Towns of Mammoth and June Sunday morning and into the afternoon. Amounts are uncertain depending upon how much moisture remains when the cold air arrives Sunday AM.
Back to the details of Thursdays/Friday’s Storm….
A large deep upper low near 50N/132W will initially steer a very dynamic impulse through a deep area of low pressure into the pacific northwest tonight. Thereafter, strong southern stream energy approaches Southern and Central CA later Wednesday. This will provide an extensive surge of pacific moisture directed at much of California. The fetch appears to have both Subtropical moisture from north of the ITZ, combined with eastern pacific tropical storm Seymour inflow. This is not actually an “AR” but the effects would be similar because of the strong moisture transport ahead of the short wave and the subtropical upper jet reaching deep into the subtropics. The big question this morning is….how quickly will the moisture move out or get cut off? This is because, as the long the fetch remains intact, the faster the rainfall totals will accumulate. Forecast models are not all that good in handling tropical moisture influx in this part of the world. So no doubt they will be playing catch up as time gets closer and the timing becomes more clear.
As a comment……..Burn scar areas along highways 395 dodged a bullet last storm that brought about 4.00 inches of rain to Mammoth Lakes two weekends ago. This coming Thursday into Friday afternoon storm has the potential to bring another 2 to 3 inches of rain at this time. 7 day forecasts of QPF are again in the 4 to 5 inches range again according to WPC’s QPF center.