WEATHER ALERT

[sparky]

This storm developed. Very cold and windy. Anyone up there tonight without winter gear is in for a cold night!

[Rockchucker]

It is raining at millpond right now, looks very black up Paiute and Bishop passes.

[giantbrookie]

This storm developed. Very cold and windy. Anyone up there tonight without winter gear is in for a cold night!

Indeed. I'm hoping for safe returns for everyone who is up there right now. In Fresno, I wouldn't say very cold, but we have dropped some 20 degrees from where we were, and it is quite windy. It did in fact rain a bit here late in the afternoon too, so this will get wet and fierce up there at altitude.

[Wandering Daisy]

We just returned from Rock Creek. Crystal clear at 10AM. Drove north, hit rain on Monitor Pass. Rained steady and heavy all the way to Sacramento. Some spots you could hardly see the road with wipers going full blast. Today the rain was quite warm. Supposed to get colder tonight. Snow down to 6,000 feet so they say.

[RichardCullip]

This storm chased us out of the Big Pine Creek backcountry one day early. We had 50mph wind gusts on Friday night so made the decision to hike out early Saturday instead of staying until Sunday as originally planned. No sign of rain or snow as we left and we got out by 11AM Saturday morning. Heard it was snowing on Donner Pass and Mammoth Lakes. Hope all others make it out safely, or, if they decide to stay, that they are prepared for the weather.

[SSSdave]

The thing I like about this first winter front of the season visiting California and the Sierra Nevada is how the forecast varied from the first sign it might occur through the week leading up to today. Thus members not that familiar with our weather might take notice and soberly consider the next time they decide to embark on an extended trip during this fall period simply because weather forecasters paint something not to worry about. Weather forecasts are vastly improved and more accurate in this era. But regardless the more days in advance, the less accurate weather forecasts be.

In this case a day or three before maverick opened the thread, I read the long range forecast discussions that reported computer models were showing a visit by a cold front. At the time of maverick's OP they expected something a bit less than what occurred today that would mainly impact areas of the northern Sierra. At that point here in the SF Bay Area, a couple of the more technically competent tv forecasters mentioned it as a possibility. Then a day or two later some of the less competent suddenly were trumpeting probable unsettled weather over the following weekend. Then over a few days computer models and NWS forecasters began to back off moving the precip further north. And then the more competent tv weather people adjusted to that quickly while the less competent moved to claim the storm would only barely impact areas north of San Francisco while areas to the south would only receive stray showers.

Generally less competent media forecasters tend to want to make their public predictions sound more certain with few relative terms in order to sound like they know what they are doing. On the other hand the raw source of their forecasts, NWS forecasters, tend to use relative terms because they understand relative accuracies of computer models and limitations on their own educated guessing.

So then on Friday as the NWS finally could see the approaching storm begin to move in on the BC coast in Canada, they could see it was going to impact California more like they had originally thought. And suddenly Friday night all the TV weather forecasters who by that time noticed they had been jerked back and forth, were by then keeping in close touch with their expert sources. So Friday night they all were forecasting rain all over the SF Bay region down to Monterey with perhaps a quarter to half inch in the North Bay and a tenth in the South Bay. And Reno and Hanford NWS forecasts upped their storm predictions likewise. But then by sunrise Saturday morning, radar returns showed it had intensified with stronger rains than expected and that was reflected in the way it dropped more precipitation, drove further south than Monterey and impacted areas east in the Sierra similarly in kind. And as a chronic weatherholic over decades, have seen a lot of forecasts that miss their mark and some will always.

[franklin411]

Pretty crazy considering how warm and pleasant it was Wednesday through Friday nights. I hiked out from Hamilton lakes yesterday because I was too lonely and passed some kids heading in towards Bearpaw. The girl was wearing shorts and a t shirt, and the two guys wore the same but they had regular school type backpacks. One kid was drinking a beer. Must have been pretty miserable for them. I got out early and couldn't find any open campsites despite trying just about everything on the generals highway. So I booked a hotel in fresno and I'm there now. It got super cold around 6 when I left kings canyon, and the clouds were so low I couldn't see more than 20 feet. I also saw 2 fire trucks and 2 ambulances going up 180, which was a bad sign. Hope those kids learned a lesson but didn't get hurt!

[Wandering Daisy]

http://www.nohrsc.noaa.gov/snow_model/i ... Nevada.jpg" onclick="window.open(this.href);return false;

Here is the satellite view of snow as of 6AM this morning. I am not sure if this image refreshes. If it does then go back to the Sept 22 date.

[KathyW]

The webcams show snow in the Bishop area and its melting fast, but not much down around Whitney/Williamson or over in Mineral King. I'm looking forward to heading out on Thursday or Friday for a few days - it should be cool and dry next weekend based on what the forecast says now.

[maverick]

Another system moving in tomorrow (Tue), it will impact northern SEKI, central Sierra
but will impact Yosemite the hardest. A 1/4" of snow possible in some areas, but very
cold temps and windy conditions are of main concern for those who are out till Thursday.
Night time temps depending on elevation will dip to sub 20 temps with days only getting
into the the low 40's, be prepared and stay warm.

NWS:

THE MAIN FORECAST CONCERNS WITH THIS NEXT STORM ARE COLD
TEMPERATURES AND WINDS. THE MODELS ARE IN AGREEMENT WITH 850-MB
TEMPERATURES PLUNGING 8-9 C OVER TUESDAY NIGHT AND WEDNESDAY
MORNING AND BOTTOMING OUT AT 7.5-8.5 C...WITH THE SNOW LEVEL FALLING
TO AROUND 7000-7500 FEET NEAR YOSEMITE. PEOPLE TRAVELING TO YOSEMITE
NATIONAL PARK TUESDAY THROUGH WEDNESDAY NIGHT SHOULD BE PREPARED FOR
A SHARP CHANGE IN TEMPERATURES TUESDAY NIGHT...AND COOL AND WINDY
CONDITIONS WEDNESDAY. ALTHOUGH QPF IS FORECAST TO BE LIGHT AND
LIMITED TO THE CREST NORTH OF KINGS CANYON BUT A BIT MORE WIDESPREAD
IN THE YOSEMITE PARK...LIGHT SNOW COULD LOCALLY FALL AS LOW AS 7000
FEET IN THE PARK WITH ACCUMULATIONS FROM A DUSTING TO A QUARTER INCH.