Active weather pattern (San Francisco, Monterey, Sonoma: vs, rating, best)

[sdurbanite]

Originally Posted by Gentoo

So it rained pretty much all morning yesterday. San Diego now has a rainfall total of 0.38in for September.

The rain ended around noon and the temperature got to 99 degrees with a heat index of 105 in Chula Vista.

Currently it is 96 with a heat index of 98. The dew point has fallen to 64 but still enough to create a slight heat index. The low this morning was 73.

Two more days of this and I return to the Bay Area. Can't wait.

Yesterday, I recall seeing the dewpoint at 72 degrees for Chula Vista. You will never see it that high anywhere in the Bay Area, with temps around 100 degrees. As a matter of fact, I don't think I've ever seen dew points readings (during heatwaves) over 55 degrees up there, but I could be wrong.

Sorry to see you go, now I won't have anyone to talk weather with when you leave. sav858 was the other one who left last year. Best of luck to you!

[Gentoo]

Originally Posted by sdurbanite

Yesterday, I recall seeing the dewpoint at 72 degrees for Chula Vista. You will never see it that high anywhere in the Bay Area, with temps around 100 degrees. As a matter of fact, I don't think I've ever seen dew points readings (during heatwaves) over 55 degrees up there, but I could be wrong.

Sorry to see you go, now I won't have anyone to talk weather with when you leave. sav858 was the other one who left last year. Best of luck to you!

Thanks man. I saw the dew point get to 72 once before in the late 90's. High 60's are usually the highest for SD. The Bay Area is really fortunate with it's dew points. I remember a relative of mine saying it was really humid there once. I looked up the dew point and saw it was like 61. I laughed. One doesn't know real humidity until they've experienced 66 or higher.

Currently in Chula Vista it's 77 but the dew point has fallen to 56.

[BayAreaHillbilly]

If it were Winter the following would be a formula for snowfall at sea level:

THE NEXT THREAT WILL BE THUNDERSTORMS. AS THE UPPER RIDGE IN THE
GULF OF AK AMPLIFIES THE DOWNSTREAM UPPER LOW DIGS SOUTH AND EAST
TO JUST OFF THE SO CAL COAST BY MIDNIGHT FRIDAY AND INTO SATURDAY.
THIS DEVELOPS EAST WINDS FROM ABOUT 5000 FT UP FROM MONTEREY
NORTH. CONVECTION DEVELOPING OVER THE SIERRA SHOULD THEN DRIFT
WEST INTO THE SACRAMENTO VALLEY AND THEN INTO OUR FORECAST AREAS
FROM ABOUT MONTEREY NORTH. THERE IS JUST MARGINAL MOISTURE SO
THERE IS A RISK OF DRY THUNDERSTORMS ESPECIALLY EAST BAY
MOUNTAINS. MODELS DO SHOW SOME MOISTENING SUNDAY BUT MOST LIKELY DO
TO RESIDUAL MOISTURE FROM THE CONVECTION FROM SATURDAY. THUS ANY
THUNDERSTORMS SAT NIGHT INTO SUN COULD BE WETTER. SO BIGGEST RISK
FOR FIRE STARTS WOULD BE LATE FRI INTO SAT. AFTERNOON FIRE WEATHER
PACKAGE WILL BE COORDINATED WITH OUR PARTNERS TO THE EAST OF US AS
TO HOW TO DEAL WITH THE POTENTIAL THREAT.

[BayAreaHillbilly]

Just checked radar. Looks like some thunder may be headed this way, hitting tonight.

[BayAreaHillbilly]

Looks like we're going to get some action here shortly. Radar, IR and water vapor all show a substantial cell moving over the East Bay and heading West.

[BayAreaHillbilly]

Backward look at August in Nor Cal:

NOUS46 KMTR 130518 RRA
PNSMTR
CAZ006-505>513-516>518-528>530-130000-

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1020 PM PDT MON SEP 13 2011

...AUGUST 2011 CLIMATE SUMMARY...

...COOLER-THAN-NORMAL CONDITIONS CONTINUE...

SUMMARY FOR THE SAN FRANCISCO BAY AREA AND MONTEREY BAY AREA...

THE WEATHER PATTERN DURING AUGUST WAS VERY PERSISTENT...SIMILAR TO
WHAT IT HAS BEEN FOR MUCH OF THE SUMMER. A BROAD UPPER LEVEL RIDGE
REMAINED ANCHORED OVER THE SOUTHERN PLAINS AND DESERT SOUTHWEST...
WHILE A WEAK UPPER TROUGH MAINTAINED A POSITION ALONG THE WEST
COAST...OR JUST OFFSHORE. THE UPPER RIDGE EXPANDED TO THE WEST AND
OVER CALIFORNIA BRIEFLY NEAR THE END OF THE MONTH AND PRODUCED A
SINGLE DAY OF ABOVE NORMAL TEMPERATURES ON TUESDAY THE 23RD.
TEMPERATURES ON ALL OTHER AUGUST DAYS WERE EITHER NEAR NORMAL OR
BELOW NORMAL. AVERAGE HIGH TEMPERATURES FOR THE MONTH WERE GENERALLY
FROM 2 TO 4 DEGREES BELOW NORMAL. AUGUST MARKED THE SEVENTH
CONSECUTIVE MONTH WITH BELOW NORMAL TEMPERATURES ACROSS THE REGION.

THE MONTHS OF JUNE...JULY...AND AUGUST COMPRISED A COOLER-THAN-
NORMAL SUMMER SEASON. SIMILAR TO THE SUMMER OF 2010...SUMMER 2011
WAS ONE OF THE COOLEST ON RECORD AT A FEW NATIONAL WEATHER SERVICE
CLIMATE STATIONS IN THE SAN FRANCISCO BAY AREA AND MONTEREY BAY AREA.
BELOW IS A LISTING OF SELECT CLIMATE STATIONS WITH THEIR AVERAGE
SUMMER TEMPERATURES FOR 2011 AND 2010 AND HOW THOSE SUMMER AVERAGES
RANK COMPARED TO ALL OTHER SUMMERS OF RECORD IN TERMS OF THEIR
COOLNESS.

AVERAGE AVERAGE
SUMMER SUMMER
TEMP TEMP YEARS OF
2011 RANK 2010 RANK RECORD
------ ---- ------ ---- --------
MONTEREY 57.4 1 57.6 2 62
MOUNT DIABLO JUNCTION 67.1 2 67.4 7 58
SALINAS 60.8 9 60.5 6 53
OAKLAND 62.9 10 62.3 2 41
REDWOOD CITY 66.7 13 65.8 6 80
SANTA CRUZ 62.1 28 62.4 34 117
SAN JOSE 67.8 36 67.6 33 87
SAN FRANCISCO DOWNTOWN 59.7 42 59.0 27 137

[BayAreaHillbilly]

As the massive Arctic outburst moved into the North American heartland this week, a piece of energy broke off it. Got a pretty good dry shortwave through here yesterday. Fall is truly here. Now, the countdown to the first rain bearing mid latitude systems.

[BayAreaHillbilly]

We're now having classic "Indian Summer" here in NorCal. However:

OVER THE WEEKEND INTO NEXT WEEK THE PATTERN BECOMES MORE
INTERESTING AS AN UNUSUALLY DEEP TROF FOR THIS TIME OF YEAR
(STANDARD DEVIATIONS AS LOW AS MINUS 4 FOR 500 MB HEIGHTS) MOVES
TOWARD THE PACNW COAST. THERE REMAINS AN OUTSIDE SHOT OF THUNDER
MOVING TOWARD THE CENTRAL COAST REGION ON SATURDAY AS A WEAK LOW
SETS UP TO THE SOUTH WITH A HIGH OFF TO THE EAST. IN THEORY THIS
WOULD BE ENOUGH TO HELP DIRECT SOME SUBTROPICAL MOISTURE OUR WAY.
VAST MAJORITY OF MODEL SOLUTIONS HAVE INDICATED THIS AS AN OUTSIDE
SHOT AS AN OUTSIDE SHOT AS BEST CASE DUE TO A LACK OF A GOOD
SUBTROPICAL TAP TO ACCESS ALTHOUGH 06Z GFS JUST IN IS RUNNING MORE
BULLISH THAN PREVIOUS RUNS. WILL LET THE DAY CREW LOOK AT THE NEXT
SUITE OF SOLUTIONS TO SEE IF THEY FEEL IT IS WORTH MENTIONING.

FOR SUNDAY MODEL SOLUTIONS DIFFER WITH WHAT WILL HAPPEN AS THE
ECMWF CONTINUES TO SHOW A LOW AHEAD OF THE LONG WAVE TROF MOVING TO
THE CWA. WITH THIS SCENARIO THE LOW BRINGS MOISTURE FROM TYPHOON
SONCA TO OUR AREA. THE GFS/GEM SOLUTIONS DO NOT BRING A LOW
OVER...INSTEAD THEY KEEP THE MOISTURE WITH THE TROF AND BRING IT
IN A LARGE SWATH TO THE PACNW MONDAY INTO TUESDAY. DUE TO THE
USUALLY BETTER FORECASTING MARKS OF THE ECMWF... DECIDED TO PUSH
POPS INTO THE SLIGHT CATEGORY FOR SUNDAY THROUGH SUNDAY WITH THE
MAIN FOCUS OVER THE NORTHERN HALF OF THE CWA. THUNDER WAS ALSO
ADDED FOR SUNDAY DUE TO THE POSSIBILITY OF THE TROPICAL ORIGINS.
REGARDLESS OF WHICH ONE VERIFIES

[BayAreaHillbilly]

NWS now backing off on precip for early next week and prog'ing the low to come in further north. In any case, a big cool down appears to be on the way.

[Gentoo]

Well someone else will now need to take over for the SoCal weather. I'll have to find another hobby LOL