altadenablog

Stormwatch Sat. AM: The rain is here, flash flood warning in effect

The Altadena Weathercam at 9 AM says it all!

National Weather Service says there's still a danger of flash floods.  Some weather stations have already recorded over one inch since it began (Bill Westphal's Weathercam station has already recorded 1.26 since midnight):

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 AM PST FOR THE STATION...MORRIS AND SANTA ANITA BURN AREAS IN CENTRAL LOS ANGELES COUNTY...

PERIODS OF HEAVY RAINFALL HAVE OCCURRED ACROSS THE RECENT BURN AREAS IN CENTRAL LOS ANGELES COUNTY SINCE 230 AM...WITH SEVERAL AUTOMATED GAUGES REPORTING OVER 1.00 INCH. ADDITIONAL BANDS OF HEAVY RAIN AND A SLIGHT CHANCE OF THUNDERSTORMS WILL CONTINUE TO SPREAD ACROSS THE WARNING AREA...WITH RAINFALL RATES EXCEEDING ONE HALF INCH PER HOUR AT TIMES. IF THUNDERSTORMS WERE TO DEVELOP...RAINFALL RATES UP TO 1.00 INCH PER HOUR WILL BE POSSIBLE. RAIN AT THESE INTENSITIES WILL LIKELY CAUSE FLASH FLOODING AND DEBRIS FLOWS IN AND AROUND THE RECENT BURN AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING FOR A RECENT BURN AREA MEANS THAT FLOODING AND DEBRIS FLOWS ARE IMMINENT OR OCCURRING. RESIDENTS LIVING IN OR IMMEDIATELY DOWNSTREAM SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. QUICKLY MOVE AWAY FROM THE BURN AREA ONLY IF IT IS SAFE TO DO SO...OTHERWISE SHELTER IN PLACE AND MOVE TO A SECOND STORY OR THE HIGHEST LOCATION IN YOUR HOME TO STAY OUT OF THE PATH OF FAST-MOVING WATER AND DEBRIS FLOWS.

Rain tonight & tomorrow, flash flood watch in effect

Relaying a message from Carolyn Seitz of the sheriff's Community Advisory Committee:

As of 11 am this morning, the County's Unified Command has issued the following information in preparation for the storm event expected to affect the Foothill burn areas, including Altadena.

The Unified Command consists of the Los Angeles County Fire Department, Los Angeles County Sheriff's Department and the Los Angeles County Department of Public Works.

WEATHER    Rain is expected to begin around midnight tonight and continue until 4 pm Saturday, February 27th.  Rainfall is anticipated to be up to 3 inches with the possibility of Thunderstorms that may produce rainfall at a rate greater than 1/2 inch per hour.

DEBRIS BASINS    The County Department of Public Works has many of the debris basis fully cleared and at 100% available capacity.   They believe that others that are not yet at 100% capacity have been cleared to the greatest extent possible and they believe the basis will have adequate capacity to accommodate this particular storm event.

ROAD CLOSURES    There are no new road closures expected for Altadena, except the existing closure at the Chaney Trail Gate.

MANDATORY EVACUATIONS    There are no announced nor anticipated evacuations for Altadena at this point, except that Millard Campground remains closed.  There are mandatory evacuation orders for portions of La Canada and La Crescenta.  A total of 244 residences will be under mandatory evacuation orders in those communities, with 85 of these in La Crescenta and the remainder in La Canada.   The mandatory evacuation order in these areas well begin at 4 pm today with evacuation completed by 6 pm.  All of the agencies are asking for mandatory evacuation orders to be honored for the protection of the residents and for the protection of all emergency responders.

INCIDENT COMMAND POSTS    are being set up today.  Los Angeles County Fire will set up a Command Post at Camp 2 by 3 pm and the Fire Department will have augmented staffing to respond if issues arise.  Los Angeles County Sheriff's Department will have a Command Post set up at Descanso Gardens by 3 pm today and will also have augmented staffing in the area to respond to issues, conduct the evacuation and to protect the evacuated areas.  The Los Angeles County Department of Public Works will also be working in the evacuation areas and will continue to monitor all of the debris basins and intakes 24 hours per day.

ADDITIONAL INFORMATION    is available at www.dpwcare.org and information on anticipated rainfall, flooding, mud and debris flows is available here:  http://dpw.lacounty.gov/wrd/forecast/file/mud4cast.pdf

As always, stay safe and don't forget to attend tomorrow's Neighborhood Watch Conference at Loma Alta Park to learn more about ways you can protect yourself and your family.

Carolyn

And from the National Weather Service:

...FLASH FLOOD WATCH FOR THE RECENT BURN AREAS IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY EVENING...

THE NATIONAL WEATHER SERVICE IN LOS ANGELES/OXNARD HAS ISSUED A

* FLASH FLOOD WATCH FOR THE RECENT BURN AREAS IN LOS ANGELES COUNTY. THIS INCLUDES THE STATION...MORRIS AND SANTA ANITA BURN AREAS.

* FROM LATE TONIGHT THROUGH SATURDAY EVENING

* RAIN WILL DEVELOP AFTER MIDNIGHT AS THE MAIN FRONTAL BAND MOVES INTO THE AREA AND WILL PERSIST THROUGH SATURDAY AFTERNOON. RAIN WILL THEN TURN SHOWERY BY SATURDAY EVENING. PEAK HOURLY RAINFALL RATES SHOULD OCCUR AFTER SUNRISE AND PERSIST THROUGH NOON ON SATURDAY. RAIN AND SHOWERS WILL BE HEAVY AT TIMES...AND THERE IS A CHANCE OF THUNDERSTORMS. THERE IS THE POTENTIAL FOR RAINFALL RATES BETWEEN ONE INCH AND ONE AND ONE HALF INCH PER HOUR. THESE RATES ARE IN EXCESS OF THRESHOLDS DETERMINED BY THE USGS TO BE SUFFICIENT TO CAUSE FLASH FLOODING AND DEBRIS FLOWS IN AND BELOW THE RECENT BURN AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION.

YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION SHOULD FLASH FLOOD WARNINGS BE ISSUED.

Stormwatch: rain tonight, watch for mud and debris, Canyon Crest impacts

Our local contact on county matters Carolyn Seitz has sent us the following:

The Los Angeles County Department of Public Works has released information on the storm expected to arrive in our area around 6 pm Friday, February 19.

The National Weather Service is predicting rainfall of 1 to 2 inches in the foothill areas between Friday afternoon and Saturday morning, with a slight chance of thunderstorms Friday night and early Saturday morning that may produce higher rainfall amounts.

The mud and debris flow alert reminds us all that we should anticipate that mud and debris may flow down the canyons below the burn areas, in the watercourses and streams.  In Altadena, it means that there is still a potential for impact on Canyon Crest.

The County continues to prepare, and will be monitoring the debris basins during the storm, and as many of you are aware, will continue to clean the basins and inlets, before, during and after the storm.

There is no evacuation anticipated for Altadena, except that the Millard Campground area remains closed.

There are no road closures in Altadena except the existing closure at the Chaney Trail Gate.

As the agencies release updated information, I'll pass along what is released.

If you're interested in seeing the mud and debris flow predictions - the "mudcast" as it's being called, you can find the information at this location:  http://dpw.lacounty.gov/wrd/forecast/file/mud4cast.pdf

As always, stay safe and stay prepared.

Carolyn