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thunderstorms

Posted: Thu Jul 25, 2013 4:05 pm
by The hermit
Does anyone know about thunderstorm activity over emigrant wilderness lately? Thanks in advance.

Re: thunderstorms

Posted: Thu Jul 25, 2013 4:12 pm
by maverick
Flood Advisories in effect, thunderstorm activity till mid-day Sunday. 40% to
50% POP on Thur-Fri-Sat, 20% POP on Sunday.

NWS:
MONSOON UPPER HIGH IS CENTERED OVER NORTHWEST ARIZONA WITH A WEAK
UPPER LOW OVER THE EASTERN PACIFIC. SOUTHERLY FLOW BETWEEN THESE
FEATURES HAS ALLOWED MOISTURE TO MOVE NORTH ALONG THE SIERRA. THIS
HAS CAUSED STRONG THUNDERSTORMS TO DEVELOP NEAR THE CREST. MODEST
SOUTHWEST FLOW HAS KEPT THE STRONGEST STORMS EAST OF THE
CREST...ALTHOUGH THERE HAS BEEN SOME TENDENCY FOR THE STORMS TO
BUILD WEST AWAY FROM ANVIL MOVEMENT. WILL MAINTAIN ISOLATED
THUNDERSTORMS OVER THE SIERRA/SCATTERED NEAR THE CREST THROUGH THE
EVENING AND OVERNIGHT. ONSHORE FLOW CONTINUES OVER THE DELTA WITH
WINDS GUSTING TO 30 MPH. TEMPS ARE RUNNING 2-6 DEGREES COOLER
VERSUS YESTERDAY OVER THE DELTA AND SRN SAC VALLEY. MUCH WARMER
OVER THE NRN VALLEY.

PATTERN WILL REMAIN SIMILAR THROUGH SATURDAY WITH A GRADUAL
INCREASE IN WESTERLY FLOW AS WEAK UPPER LOW MOVES EAST. THIS WILL
TEND TO KEEP MOST THUNDERSTORM ACTIVITY ALONG THE CREST OR EAST.
WEAK ONSHORE FLOW WILL HELP TO MODERATE TEMPS WITH READINGS NEAR
TO SLIGHTLY ABOVE NORMAL.

MOISTURE WILL SHIFT EAST OF THE AREA ON SUNDAY AS BROAD TROUGH
DEVELOPS OVER THE PACIFIC NORTHWEST BRINGING INCREASED WESTERLY
FLOW. THIS WILL END THE THUNDERSTORM CHANCES OVER THE SIERRA.
TEMPERATURES WILL COOL TO NEAR OR SLIGHTLY BELOW NORMAL LEVELS.

Re: thunderstorms

Posted: Thu Jul 25, 2013 4:15 pm
by DoyleWDonehoo
Heading out that way tomorrow. This is the forecast for the North Fork Cherry Creek area:

Friday A 20 percent chance of showers and thunderstorms after 11am. Mostly sunny, with a high near 77. Light and variable wind becoming west 8 to 13 mph in the afternoon. Winds could gust as high as 20 mph. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Friday Night A slight chance of showers and thunderstorms. Partly cloudy, with a low around 51. West wind 5 to 9 mph becoming east northeast in the evening. Chance of precipitation is 20%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Saturday A slight chance of showers, with thunderstorms also possible after 11am. Mostly sunny, with a high near 74. Calm wind becoming west southwest 5 to 9 mph in the afternoon. Chance of precipitation is 20%.

Saturday Night A 20 percent chance of showers and thunderstorms before 11pm. Partly cloudy, with a low around 50.

Sunny and clear hereafter

Probably good news: Cooler and less sun for the slog out into the hinterland. Looking at the cams, it is pretty cloudy.
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Re: thunderstorms

Posted: Thu Jul 25, 2013 4:37 pm
by maverick
According to NWS site forecast the more east, towards 395, one goes the POP percentages
go up, and extends into Sunday morning.

Re: thunderstorms

Posted: Thu Jul 25, 2013 5:04 pm
by The hermit
Thanks for the swift responses. That helps w/ my decision to leave the dog at home. Seems like a pretty normal pattern. Afternoon showers clearing later in the evening. Will be prepared for some moisture! First trip of the year. Can't wait! Thanks again.

Re: thunderstorms

Posted: Thu Jul 25, 2013 6:16 pm
by rlown
flew back from Plano last night. Flew the normal path into SFO right over Yose. The moisture was obviously piled up even before that and still streaming in. Pilot was at 38k and we were still dodging thunderheads and moisture before we hit Nevada.

I never get bored of looking down on Mono Lk from an airplane. An hour earlier would have been more interesting as the sun was just setting. I could make out some of the lakes like saddlebag, Tenaya, etc in that area.

Be prepared this weekend up there.

Re: thunderstorms

Posted: Thu Jul 25, 2013 8:24 pm
by SSSdave
First appearance of thunderstorms was last Sunday which was minor then Monday developed strong thunderstorms before waning as high pressure backed off to the east. This is all excellent news to this person because the Sierra is so dry. Sunny areas I visited last week on the Great Western Divide had considerable brown grasses which is more normal for mid August. Several bouts of general thunderstorms across the range could make August backpacking more pleasant and for this person much more aesthetically green.

As for the weather forecast during monsoonal conditions, take any forecast with a huge grain of salt as one could spend all day under heavy rain and hail with gully washers while just a few miles away are only sprinkles. Such was the case last year during our Silver Divide trip where from Graveyard Lakes under light rain at most we watched the Bear Creek areas get absolutely pounded by monsterous towering black buildups thundering with constant lightning, that I recall a couple on this board were caught in.