SLOweather

My local Wxsim forecast has been inconsistent over the last few runs. Now I know why. This is from the early morning NWS forecast discussion:

—

000
FXUS66 KLOX 291052
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
345 AM PDT MON OCT 29 2007

.SHORT TERM…
FORECASTING TODAY IS ONE ONLY FOR THE BRAVE. THERE IS A GREAT
POSSIBILITY THAT TODAYS FORECAST WILL BE WRONG. THE CURRENT FORECAST
MAY BE TOO OPTIMISTIC OR EQUALLY IT MAY BE OVERLY PESSIMISTIC.

SUCH PROBLEMS USUALLY STEM FROM CUT OFF LOWS AND TODAY IS NO
EXCEPTION. THE LOW IS NOW ABOUT 450 MILES WEST OF POINT CONCEPTION
AND IS MOVING TOWARDS THE ENE. THERE IS ALSO A PLUME OF SUB TROPICAL
MOISTURE MOVING NORTHWARD AND INTO THE UPPER LOW`S FLOW. HOW THESE
TWO FEATURE INTERACT WILL DETERMINE THE FORECAST FOR THE NEXT 24
HOURS.

Cathy Gregg, the lady that took those spectacular lightning shots of last October’s lightning storm has a 10 minute slide show of the Zaca fire up on YouTube:

Whilst viewing that, I noticed other Zaca Fire vids in the Related Videos area. This time lapse is quite interesting:

http://uk.youtube.com/watch?v=w07xyvvLaUk

And a closeup of the DC-10 dropping PhosChek:

http://uk.youtube.com/watch?v=ZbKXszNV7DM

There are lots more Zaca vids available there, and I’m sure some of them are interesting (some are, uh, dorky).

Friday afternoon, Katie and I spotted a pair of white-tailed kites patrolling for food in our neighborhood.

This is a reduced copy of the original picture:

Cropped and slightly enhanced to make the bird more prominent:

Another view:

Well, it’s not quite the “Blood Moon” that I anticipated. Since Halloween is a week from last night, maybe this one is more of a Pumpkin Moon…

Tonight’s full moon for October, the Full Hunter’s Moon, rises locally at 5:48 PM PDT. It should attain fullness at 9:52 PM PDT.
Other names for it are the Blackberry Moon, and the Blood Moon. If there is still residual smoke in the air to the east
tonight, it may indeed look a little bloody. Last night’s moon was a nice pumpkin orange. The forecast is for partly cloudy skies.

In the time that I’ve been watching the NWS watches, warnings, and advisories, this is the first Red Flag Warning for the SLO County coastal areas that I can recall:

Red Flag Warning

RED FLAG WARNING
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
421 PM PDT TUE OCT 23 2007

…RED FLAG WARNING IN EFFECT UNTIL WEDNESDAY AFTERNOON FOR SAN LUIS OBISPO…VENTURA COUNTIES AS WELL AS SANTA BARBARA COUNTY EXCEPT FOR THE SOUTH COAST AND LOS ANGELES COUNTY EXCEPT FOR ANTELOPE VALLEY FOR PROLONGED VERY LOW RELATIVE HUMIDITIES AND EAST AND SOUTHEAST WINDS THROUGH WEDNESDAY EVENING..

.SANTA ANA WINDS WILL CONTINUE TO WEAKEN WHILE HIGH PRESSURE OVER THE GREAT BASIN SHIFTS EAST OVERNIGHT. OFFSHORE WINDS WILL PREVAIL TONIGHT WITH THE STRONGEST WINDS WILL OCCUR OVER THE HIGHER
TERRAIN AND IN THE VICINITY OF PASSES AND CANYONS. A WIND ADVISORY CONTINUES FOR ENTIRE VENTURA COUNTY AND AREAS OF LOS ANGELES COUNTY TONIGHT.

A WEAK PRESSURE GRADIANT WILL DEVELOP OVER THE AREA LATE WEDNESDAY AND PERSIST THROUGH SATURDAY AND DIURNAL WIND SHIFTS WILL RESULT. RELATIVE HUMIDITIES WILL BEGIN TO RECOVER ATTHE COAST AND IN THE COASTAL VALLEYS
AS A SEABREEZE BECOMES ESTABLISHED BY WEDNESDAY AFTERNOON AND REDEVELOPS EARLY AFTERNOON THROUGH SATURDAY. WHILE THE COASTAL HUMIDITIES BEGIN TO RECOVER THE INLAND AREA WILL LAG BEHIND AND THE RED FLAG WARNING MAY BE
EXTENDED FOR HIGHER ELEVATIONS DUE TO PROLONGED VERY LOW RELATIVE HUMIDITY THROUGH THURSDAY.

CAZ234-241730-
/O.CON.KLOX.FW.W.0017.000000T0000Z-071024T2300Z/
SAN LUIS OBISPO COUNTY COAST-
421 PM PDT TUE OCT 23 2007

…RED FLAG WARNING REMAINS IN EFFECT UNTIL 4 PM PDT WEDNESDAY FOR PROLONGED VERY LOW RELATIVE HUMIDITY..

A RED FLAG WARNING REMAINS IN EFFECT UNTIL 4 PM PDT WEDNESDAY.

VERY LOW RELATIVE HUMIDITIES AROUND 10 PERCENT WILL PERSIST THROUGH WEDNESDAY AFTERNOON. THE HUMIDITY WILL REMAIN LOW AS EAST WINDS AROUND 10 MPH AND LOCALLY HIGHER TO 20 MPH AND TO 30 MPH OVER THE EXPOSED RIDGE TOPS PERSIST OVERNIGHT. THE WIND WILL GRADUALLY WEAKEN AND BECOME LIGHT ONSHORE BY WEDNESDAY AFTERNOON…HUMIDITY
WILL GRADUALLY RECOVER BY WEDNESDAY AFTERNOON.

Things cooled off a bit over night and the wind shifted around and cleared out the smoke.

However, low humidity and high temps are again leading to extreme fire conditions for the SLOweather area. This morning’s SLOweather Wxsim forecast is in close agreement with the NWS, with a high of 90, and winds shifting from the east to the northwest.

At 9AM, though, the relative humidity is only 18% and will continue to drop through as the temperature increases. Wxsim says it could drop to 13%. I won’t be surprised if it goes lower. Humidities are forecast to begin to rebound, however, over the next few days, as high temperatures drop a bit as well.

This morning’s sunrise was colored by smoke from one of the many fires burning around Souther California. Today’s local forecast is calling for more hot, dry temperatures, and low relative humidities as well. Sunday’s RH at SLOweather dropped to 12%. The forecast fire danger for today, Monday is:

October is Fire Prevention Month, which is a good reminder to change the batteries in your smoke detector. They should be replaced every year if you are using alkaline batteries, or every ten years if your are using the long-life lithium batteries. You shouldn’t cheap out and use zinc-carbon or “heavy-duty” batteries.

The mantra used to be to change your smoke detector batteries in the fall when Daylight Saving Time ended on the last Sunday morning in October, which made sense due to it falling in Fire Prevention month. Now that Congress has changed that date to the first Sunday in November, you will probably hear 2 reminders to change the batteries, October for Fire Prevention Month, and the traditional date of the end of DST.

One less-publicized recommendation is to replace your smoke detectors themselves every 10 years. There is a good analysis of why you should do this on the National Fire Prevention Association web site here.

And, as long as we’re on the subject, you should consider adding a carbon monoxide detector as well. These should be available anywhere you can purchase smoke detectors, and are available in models that just plug right into a wall outlet.

The story was in the Trib this morning…

And he’s on Dave Congalton right now. John Lindsey is back at PG&E in a new position, but he’ll still be doing weather, and we’ll still link to his forecasts.

Welcome back, John!