Archive for May, 2011

Quick Update for snowfall amounts:

2 to 4 inches in town

5 to 7 inches on Mammoth Mt

between tonight and mid morning

It it Spring Yet? I guess this is Spring….. Windy…chilly and snow by Midnight….

Current Conditions at 9:00am….

41 degrees at 8200 feet

28 Degrees at 11,000 with 90mph gusts!

Winds are gusting 30 to 40mph at resort levels.

Wind Advisories have been hoisted for Mono County. A High Wind Warning goes into effect at 2:00pm for the Owens Valley.

At 9:00am A cold upper low was centered over the Central Oregon coast with an HT 500 545DM center.

At 300mb….a cyclonically curved upper jet of 125 knots was across Northern Ca. This upper jet will shift through the Central Sierra tonight then south through Mammoth by Morning. Plenty of over water trajectory will transport moisture into the sierra late tonight and into Sunday am for accumulating snowfall of some 2 to 4 inches over the upper elevations over the next 30 hours. Strong gusty winds will be the theme today.

The upper HT 500 low will track SSE and will be located over SAC by 2:00am Sunday morning and will transit the Sierra as a 542dm center before 5:00am Sunday morning. UVM will rapidly increase by 8:00pm this evening and remain strong through 5:00am Sunday….then begin to diminish after 8:00am Sunday. By 11:00 the main UVM (upward vertical motion) will be over the Southern Sierra. Snowfall over the Central Sierra will be more scattered during the PM hours Sunday. A 540DM 500-1000thickness iso-hyet arrives in Mammoth at 2:00am. That is equal to about a 4000ft snow level. Needless to say that in wind protected areas of Bishop, early morning temps will flirt with the freezing mark for a short period of time. High temps in the residential sections of Mammoth will drop into the upper teens to low 20s Sunday morning then climb into the 30s Sunday Pm. This is quite the chilly system.

OUTLOOK:

There is one more system in the chain that will effect California Mid Week. This is actually an interesting scenario. What is happening is that there is going to be a fundamental change in the pattern next week into the next. Strong retrogression of an upper level ridge that will form over the Ohio Valley may cause the next system to become cut-off over, or near California. The Dweebs are not sure how this will all work out quite yet. However, the screaming message is that a fundamental transition in the pattern will occur as heights really increase over the far west causing the westerlies to weaken and jump to the north. This may be an end to an unbelievable long winter!

As far as this next storm goes……Initially, this system comes in to the far west as another chilly closed upper low, with wind and a chance of showers. As the center of an upper ridge retrogrades westward to Northern Texas, the west coast Trof gets stuck….somewhere near the west coast. Will this system progresses east, NE, or cut-off over California or just off shore? Will it become a long term cut-off low trapped within a full latitude upper ridge left to die on the vine? We may get caught up in a late Spring thunderstorm pattern. As if this system cuts off and develops in the right spot offshore, and temps soar within the upper ridge, a springtime convective TSRW pattern may develop over the sierra.  Lots to look at and think about the next week and beyond……See Yea!

The Dweeber…………………………..:-)

————————————————-
Reference Glossary of Weather Terms
Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.