Santa Ana winds ease over Los Angeles

By: Dr. Jeff Masters , 2:17 PM GMT on November 17, 2008

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The Santa Ana winds have died down over Los Angeles, and winds should remain below 25 mph today through Thursday over the region. This should allow fire fighters to gain control of the three major blazes burning near the city. Wind gusts in excess of hurricane force--74 mph--were recorded at several mountain locations Friday and Saturday, thanks to the major difference in pressure between a strong high pressure system to the northeast of Los Angeles and lower pressure air over the ocean. By 4 pm PST Sunday, though, winds had fallen below 15 mph over the entire region (Figure 1), and a weak sea breeze had formed near the coast. Taking a look at this morning's wundermap (with fire layer turned on) for Los Angeles, we can see that winds are below 5 mph over the region. All high wind warnings and fire weather warnings have been canceled for California, but continued hot and dry conditions will slow down efforts of fire fighters to control the fires. The smoke has caused pollution problems in the city, and the Air Quality Index (AQI) for particulate matter less than 2.5 microns (PM2.5) exceeded the EPA standard yesterday. Today's pollution forecast calls for PM2.5 levels in the unhealthy for sensitive groups level, in excess of the EPA standards.


Figure 1. Wundermap (with fire layer turned on) for Los Angeles, California, at 4 pm EST Sunday November 16, 2008. Two major fires, the Sylmar fire to the north, and the Freeway fire to the east, are shown. The black colors show the relative concentration of smoke. The colored circles show the temperature, and the lines going into the circles show the direction the wind is blowing from. The perpendicular lines at the the end of these lines show how strong the wind is blowing. Each longer line is an additional 10 mph, and each shorter perpendicular line is an additional 5 mph. Thus, for the circle at upper right with a 66° temperature, the wind was blowing 15 mph out of the NNE. (Note that we've changed the convention used on marine maps, where these so-called "wind barbs" denote the winds in knots, not mph).

High temperature records
The hot flow of air off the desert set numerous high temperature records across Southern California on Sunday. Records set or tied included 88° in downtown Los Angeles, 93° in Camalillo; 86° at LAX airport; 90° at Long Beach; 89° at Paso Robles; 87° at Santa Maria; 91° at Woodland Hills; 87° at UCLA; 93° at Oxnard; and 87° at Santa Barbara. On Saturday, 30 high temperature records were set or tied across the state of California, including a blistering 93° in downtown Los Angeles (old record, 90° in 1936). The hottest new record was 94° at the Santa Ana Fire Station.

The forecast
Hot and dry conditions will persist over Los Angeles today, then gradually cool Tuesday and Wednesday. On Wednesday and Thursday, winds should reverse and blow cool, moist air from the oceans over the city, allowing fire fighters to gain full control of the fires. By Saturday, the GFS model is indicating a possible return to Santa Ana wind conditions for the weekend, but the ECMWF model disagrees. At this point, it appears we may get a weak Santa Ana wind event this weekend, but nowhere near as strong as the one that just ended.


Figure 2. Visible satellite image from NASA's Terra satellite taken on Sunday, November 16, 2008 at 11:30 am PST. Smoke from the Sylmar fire 20 miles north of Los Angeles has drifted out over the Catalina Islands, joined by a larger plume of smoke from the "Freeway Fire" in Orange County.

Support the Portlight Christmas for Gulf Coast Kids Honor Walk
The Portlight.org charity is sponsoring a new nationwide grassroots event to raise funds for and awareness of their ongoing efforts, specifically to provide Christmas presents (and maybe a big party) for kids and families in the Gulf Coast areas devastated by Hurricane Ike. They need 100 people across the country to commit to walking one mile this Saturday, November 22, and to raise at least $300.00 in sponsorship from friends, family, co-workers, neighbors, etc. Participants can choose where they want to walk--the local park, the mall, anywhere. Please support this worthwhile effort!

Jeff Masters

Sayre fire (anvilhead)
Sayre fire
Sayre Fire (anvilhead)
Sayre Fire

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I think this is have another Alcohlic beverage Monday...
Member Since: September 2, 2007 Posts: 178 Comments: 20443
Quoting Cotillion:


I'd prefer it if you send over some clam chowder or a Philly cheesesteak. ;)


Clam chowder I can do,won't find too many Philly cheesesteaks in Boston
Member Since: September 6, 2007 Posts: 883 Comments: 15862
Quoting NEwxguy:


Actually being the generous new englanders that we are,alot of our nor'easters we send across the pond to share with you.


I'd prefer it if you send over some clam chowder or a Philly cheesesteak. ;)
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting Cotillion:


Yeah, was my sarcasm. Keep failing to remember it doesn't show so well in the written word!

And we have our own type of Nor'easters, so alerts closer to home.

"Weather is for life, not just for the summer."


Actually being the generous new englanders that we are,alot of our nor'easters we send across the pond to share with you.
Member Since: September 6, 2007 Posts: 883 Comments: 15862
Quoting NEwxguy:


Well,I will miss tracking the tropics,but here in new england we have the nor'easters to follow,which can be as interesting.


Yeah, was my sarcasm. Keep failing to remember it doesn't show so well in the written word!

And we have our own type of Nor'easters, so alerts closer to home.

"Weather is for life, not just for the summer."
Member Since: August 23, 2008 Posts: 7 Comments: 5300
back to missing entries on the blog
Member Since: September 6, 2007 Posts: 883 Comments: 15862
Quoting Cotillion:


End of the hurricane season does it to us all.



Well,I will miss tracking the tropics,but here in new england we have the nor'easters to follow,which can be as interesting.
Member Since: September 6, 2007 Posts: 883 Comments: 15862
Quoting NEwxguy:
GFS has been very manic lately and most forecasters are staying away from it when doing their long range.


End of the hurricane season does it to us all.

Member Since: August 23, 2008 Posts: 7 Comments: 5300
GFS has been very manic lately and most forecasters are staying away from it when doing their long range.
Member Since: September 6, 2007 Posts: 883 Comments: 15862
42. Inyo
Quoting IpswichWeatherCenter:
GFS model has forecasted Snow in London on December 1st


The GFS has been drastically erratic lately, in the last few days it has shown anything in California from the storm of the century (one weird run) to a week long continuation of Santa Anas (I hope that doesn't happen!) I'd imagine it isnt too reliable anywhere that far out.
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Oh thank you for the always memorable update Dr. Jeff Masters Phd.
Member Since: July 7, 2005 Posts: 0 Comments: 5361
Ike are you hibernating?
Member Since: July 7, 2005 Posts: 0 Comments: 5361
Hey guys.

Sad to hear about the fires, but at least the winds are calming down.

Got the infamous 'British drizzle' today. The most depressing weather we get. Le sigh.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Seastep - whooooooooa! My young buck is going to love this !!! Thanks - I'm out
Member Since: July 18, 2007 Posts: 30 Comments: 26536
Yikes Mike, no freeezies pls. That's how I feel right now!!. Off to second shift - glad the Sun is so warm - makes going out a lot easier
Member Since: July 18, 2007 Posts: 30 Comments: 26536
Good afternoon all. Just popped in to share this with all those interested in space (CyberTeddy, RobDaHood, etc.).

First pictures ever of a planet orbiting a star outside our solar system:

Link
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I just updated my blog if anyone would like to review...

TampaSpins Weather Blog Link
Member Since: September 2, 2007 Posts: 178 Comments: 20443
Gooc afternoon everyone. Busy at work today so didn't get on the blog during the AM.Chilly in the NE today and for the rest of the week.

Bondog:

I missed what the crains are for, and where they are at.
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GFS model has forecasted Snow in London on December 1st
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glad to hear surfmom =) good to hear the horses are doing fine.

Dont work to hard ;)
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Quoting leftovers:
this florida cold is good for the local orange crop

YUP, they'll be nice and sweet and VERY orange!!
Member Since: July 18, 2007 Posts: 30 Comments: 26536
Aloha MissNadia - from chilly but SUNNY SRQ - hoping your weather will warm-up a bit, the waves lay down and let you get out and do some fishing soon. Had three days of surf and I feel like I ran a marathon -- creak, creak -- Surfing is one hell of a rough sport -- feels like I was in a washing machine with stones.... never the less, I've got a good BUZZ going today -- getting ready to get off to work -- happy to report NO colicking horses from this cold front.
Member Since: July 18, 2007 Posts: 30 Comments: 26536
was born and raised in newark SW now reside on Greenwood Lake right by the NY State border.

MissNadia yea I remeber that well. Our container field used to flood during normal rains about 4 feet deep in somespots because the first contractors messed up. Now our fields drain very well and stay that way. Your brother did a great job.
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26. Inyo
BTW those are the 'Channel Islands' not the 'Catalina Islands', Catalina is one of the Channel Islands. Catalina Island is the closest one to the southwest of the fires.

I was quite close to the Tea Fire but my pictures didn't come out too well. Glad to see things calming down!
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bonedog:I lived on baldwin ave. in J.C. for about 4yrs and worked at exchange pl. in downtown,where you live near newark,I take it???
Member Since: October 5, 2007 Posts: 20 Comments: 4970
#22 Bonedog
Like I told you, the first contractor screwed it up and he and his crew were down there trying to get it level !!!
Member Since: July 27, 2008 Posts: 0 Comments: 3002
here are some photos of our crane delivery.





the cranes being delivered are the ones near the ground, completed ones are the real tall ones
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Hello Miss Nadia. The Tyler street pier would be mine =) Port Newark Conatiner Terminal, PNCT for short. The barges were morred delivering our new cranes. The pier to the north with the tug boats is a slavage company, dont know the name off the top of my head.

Your brother must have been on our pier during our multimillion dollar renovation.

Small world =)
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Morning Bonedog,
A month or so ago, I mentioned my brother was working on a dock in your area on 9-11.
He doesn't remember the dock # but the address was Tyler street and two large barges with cranes were moored alongside. The pier just North had a bunch of tug boats . Does this ring a bell?
Member Since: July 27, 2008 Posts: 0 Comments: 3002
slow blog today
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.....while all us floridains complain about our 45 degree lows!!!!!,lol
Member Since: October 5, 2007 Posts: 20 Comments: 4970
thanks doc!!!,enjoy your snow showers yesterday????
Member Since: October 5, 2007 Posts: 20 Comments: 4970
top reason to proof the picture before its entered to print

An American woman has been promoted to four-star general - the first female to reach the US Army's highest rank.

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EVEN COLDER WEDNESDAY MORNING IN TAMPA IT LOOKS LIKE...
Member Since: September 2, 2007 Posts: 178 Comments: 20443
Ooohhh, this is nice!!! the temp is amazing out, low around 50 in miami tomm night and i live a bit inland, 47!!! yummo
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thanks for putting my pictures in your blog jeff!
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13. DDR
Wow! i cant imagine myself living in a such a dry enviroment/desert.
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yea NE I noticed that. What I am actually watching is more of a shortwave induced snow. Also up by me we have had a few Lake streamers making it. Had a few squalls yesterday, nothing major, just enough to get some white stuff then the wind blew it away.

As a few folks have said, when not if, one of these troughs will pinch of and we will see a storm. All the ingredence are in place for a nice snowstorm. Just need the Low to form.

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Member Since: September 2, 2007 Posts: 178 Comments: 20443
Morning All! - I am creeping along today - three days of waves (not complaining mind you) and today feels like the day after a marathon or 50K run....perhaps I'm still defrosting.

SWFL - woke to 47 degrees, thankfully the Sun is shining bright and everything is warming up around me. We bundled up this AM -- so we've managed not to turn on the heat.... yet

Some left over surf in the Gomex from the cold front -- but there is a collar around my neck and I'm chained to the desk -- Office work needs to be completed and the Barn awaits for the second shift.
Member Since: July 18, 2007 Posts: 30 Comments: 26536
dang broward 45 degrees that cold for tuesday
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Quoting Bonedog:
Morning NE. going to be a cold 2 weeks for us. might have a storm by the weekend.


yep,winter has set in,looking at forecasts,it looks like the GFS is alone on the weekend storm right now,will be interesting to see if other models jump on board.
Member Since: September 6, 2007 Posts: 883 Comments: 15862
Complete Blog Refresh
Mirror Site (New Format)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Morning NE. going to be a cold 2 weeks for us. might have a storm by the weekend.
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another 5.1 in the artic. Just under an hour since the last one. 5.7 earlier, exact same depth though.
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Morning,all,start of the chill today,only getting colder here on out
Member Since: September 6, 2007 Posts: 883 Comments: 15862
Thanks Doc. Simply amazing how weather can be so diffrent across the country. East is in the chiller west is burning :(

Morning conchy. Hope your daughter stays safe! and isn't too affect by the smoke and particulates.

Tampa from the last blog, yea you have been saying that for quite some time now. Have been watching as well. Just wierd today how many quakes are springing up. Might be after affects of the 7.5. The pressure wave going through the planet and affecting faults and geothermal activity.
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Thank you Jeff
Member Since: October 1, 2007 Posts: 81 Comments: 26511

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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