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

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Sayre fire
Sayre Fire (anvilhead)
Sayre Fire

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I would like to encourage everyone that can to purchase a Food store gift card and give it to some family for Thanksgiving. It is what Thanksgiving is about.....

Member Since: September 2, 2007 Posts: 178 Comments: 20439
Ike,
The time is almost here for the last GFS run.
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Quoting pottery:
Good morning all
Trinidad weather-
79F temp
77% humidity
Very heavy rains yesterday caused flooding and landslides in the north of the country. A 4 year old child was killed when the house she was sleeping in was covered in a slide.
Very sad .
More rain is forecast today.


Aww, that's very sad to hear. :(

Hope none of that occurs again for when more rain comes along.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Up in Gainesville FL, I pulled up all the herbs, aloe, and pepper plants to save them from the frost today and tomorrow. Even harvested the sugar cane since it was too tall to put under a sheet.

Sorry to hear about the slide Pottery.
Sounds like a beautiful place.
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Though when I was in Florida, only took 2 or 3 days to get acclimatised to the heat, which wasn't too bad. I've got a good temperature flexibility. :)
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting surfmom:
cotillion - I can't imagine living in those temps., POST 511....That is some rough, harsh weather -- Scotland is such a beautiful country....but the winter would kill me. Do you stay inside.....do kids go out and play ????


More people are bothered by the rain than the cold, I'd wager. We're a hardy folk, we're used to it. It's when it gets hotter, I mean way hotter than normal, we encounter problems. Average for the summer, might be around 22, perhaps 26 or so in London. When on the occasion it hits around 100F... well nobody's used to it.

The last 2 winters have been really mild, last winter especially. Barely hit freezing at all, and we've had it twice this year before December. Only snowed like once last year.

People do go out, and kids still go out and play. Naturally, everyone wraps up warm. And consumes hot food. Having a cup of tea after being out in the cold all day is wonderful.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting surfmom:
Good news for me Tampa -- a little better is good to hear


I am still hoping for snow... for you.. not me :)
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Quoting stillwaiting:



morning,what a wimp...lol(joking),you still feel like going for a swim in this wonderful SWFL weather!!!!!,I've got about 1 1/2 dozen sweet roma tomato's going right now and about the same amount of jalpeno's,interested????
Going to be passing through the key at some point today, howz 'bout you put a little out by your door & I'll drop off some fresh eggs -- It's certainly cool enough that we don't have to worry about spoilage LOL
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Quoting TampaSpin:
One more nite of really bad cold in the south and things get a little better but, not much.
Good news for me Tampa -- a little better is good to hear
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Happily, as Rob mentioned, the SUN is still quite strong -- makes the 60 not so bad --- unless the winds pick up
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gm all
35F 52%

Pottery
Sorry to hear about the tragedy.
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cotillion - I can't imagine living in those temps., POST 511....That is some rough, harsh weather -- Scotland is such a beautiful country....but the winter would kill me. Do you stay inside.....do kids go out and play ????
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Quoting surfmom:
oooooh you are in some chilly turf MissNadia -- gonna have to dress warm for your outside activities today

I'll wait for the sun to get high and then go out.. don't have to keep sched.
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Quoting TampaSpin:


Only if your skinny dippin....ROFLMAO
.... LOL Tampa - so you think the neoprene is cheating????
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oooooh you are in some chilly turf MissNadia -- gonna have to dress warm for your outside activities today
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Quoting surfmom:
Hell, Tampa -- does going in the ocean today count ???


Only if your skinny dippin....ROFLMAO
Member Since: September 2, 2007 Posts: 178 Comments: 20439
Quoting TampaSpin:
Quoting surfmom:
Buenos Dias Amigo's & Amiga's 43 degree here in SRQ -- I cheated and put the heat on this morning for an hour....


If you really want to be brave....turn your hot water heater off for 1 day......LMAO
Hell, Tampa -- does going in the ocean today count ???
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530. pottery

So sorry to hear that...unfortunately, you'll probably end up with some more rain this week. Hopefully nothing too heavy. Stay safe.
Member Since: September 2, 2008 Posts: 96 Comments: 31762
patchy frost forcast for Sarasota area overnight!!!!!!!!!(tonight)....
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Quoting surfmom:
Buenos Dias Amigo's & Amiga's 43 degree here in SRQ -- I cheated and put the heat on this morning for an hour....


If you really want to be brave....turn your hot water heater off for 1 day......LMAO
Member Since: September 2, 2007 Posts: 178 Comments: 20439
SM:scrap the going for a swim,the GOM looks to have zero waves for surfing,though the tiny waves could mean good fishing,a couple friends caught some BIG seatrout at night at new pass,I may have to check that spot out when it warms a bit so I'm not freezing my but off!!!!
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Quoting surfmom:
Buenos Dias Amigo's & Amiga's 43 degree here in SRQ -- I cheated and put the heat on this morning for an hour....



morning,what a wimp...lol(joking),you still feel like going for a swim in this wonderful SWFL weather!!!!!,I've got about 1 1/2 dozen sweet roma tomato's going right now and about the same amount of jalpeno's,interested????
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Good morning all
Trinidad weather-
79F temp
77% humidity
Very heavy rains yesterday caused flooding and landslides in the north of the country. A 4 year old child was killed when the house she was sleeping in was covered in a slide.
Very sad .
More rain is forecast today.
Member Since: October 24, 2005 Posts: 0 Comments: 24028
One more nite of really bad cold in the south and things get a little better but, not much.
Member Since: September 2, 2007 Posts: 178 Comments: 20439
Quoting sullivanweather:
Rise/fall couplets in the isobaric fields will create strong winds as well. Maybe you'll have a rapidly rising/falling pressure to create the stronger winds instead of the tightly pad isobars...


Hmm, yeah. Roundabout where the B/A high and a low over Norway meet is the east coast. They are somewhat close, but didn't seem to say up to hurricane force. Maybe an element of the two, if that's possible?

On another site, wind gusts seem to be predicted at about 50 or so.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Buenos Dias Amigo's & Amiga's 43 degree here in SRQ -- I cheated and put the heat on this morning for an hour....
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520 - Conchygirl - it was a little esoteric in here last night, different dimensions and all.

521 - RobDaHood - sorry Rob, didn't mean to scare ya, thats why I only downloaded the eyes.
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Rise/fall couplets in the isobaric fields will create strong winds as well. Maybe you'll have a rapidly rising/falling pressure to create the stronger winds instead of the tightly pad isobars...
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Quoting TampaSpin:
Morning Everyone......Burr
Morning Tampa - burr is right! Must think about buying some closed toed shoes for this nippy mornings!
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Morning Everyone......Burr
Member Since: September 2, 2007 Posts: 178 Comments: 20439
Quoting sullivanweather:



It doesn't usually get that cold over there this time of year, does it??

I know for us to get down into the teens so early is kind of rare here. Mabe once every 3-4 years or so. But over there usually stays pretty mild until the end of December, no?


Yes, coldest I can remember for a while. It was around this in late October. The actual temperature is around -3, colder in rural areas. But we've got a strong northwesterly colder. Thankfully, they've backed off on the gale prediction. I thought it was a little odd at first as the synaptics didn't really show packed isobars.

January is generally the coldest month, so if it keeps this up, I'd hate to see how cold it is then. Had a look, and Aberdeen is going to get to like -10 (14F) on Sat. Brr.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
516. RTLSNK

ROFL - see what you get for throwin a spider on my screen? I don't think either species likes me very much!

Have to stop posting for a while...will be working/lurking most of day.
Member Since: September 2, 2008 Posts: 96 Comments: 31762
Morning Rob: I like the Morays' way better than spiders! I love to watch them when they are free swimming - just don't stick your hand in their hole and you'll usually be fine. They are so gorgeous (and dangerous if ya mess with them). Things sound more normal in here this morning than last night! :)
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#513 aweatherlover

Go to the top of this page and put GSO in "city state block" and scroll down .. on the right of the page will be the wx for the weekend!! LOL
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515. conchygirl

Mornin' conchy!

Long as they stay in their holes and I stay out we get along fine. Have been freaked out a bit though when I swam by right as they were coming out.
Member Since: September 2, 2008 Posts: 96 Comments: 31762
Quoting Cotillion:
However, temperatures here at the weekend are set to plummet.

Saturday will have temperatures feeling like around 17F (-8C), with Scotland likely to be even colder. Heavy snow and blizzard advisories have been issued from Scotland down to East Anglia. Gusts were mooted to reach around 70mph.

"Blizzards & Heavy Snow Sat 22 Nov

There is a moderate risk of a severe weather event affecting parts of northern and eastern Scotland and many eastern coastal areas of England. Heavy snow showers will bring accumulations of several cms in places, especially in the north and over hills, where strong winds will also give blizzard conditions at times.

Issued at: 1008 Wed 19 Nov"



It doesn't usually get that cold over there this time of year, does it??

I know for us to get down into the teens so early is kind of rare here. Mabe once every 3-4 years or so. But over there usually stays pretty mild until the end of December, no?
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Rob - I know that thing!!! If you take the scroll bar and move it up and down fast it will pop that Moray in your face just like they really do. hahaha
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Quoting RobDaHood:
For U RTLSNK

I love these guys - so fun to watch when diving!
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Also interested to hear what you guys think may happen next year on my blog. :)
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Hey all! I'm going to be in Greensboro, NC (which I believe is just outside of winston-Salem?) and I was wondering if anyone in the area could tell me what I can expect weather wise for Saturday-Tuesday. I haven't seen real snow since I was about 6 years old so that would be quite a treat. Thanks!
-Alicia
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For U RTLSNK

Member Since: September 2, 2008 Posts: 96 Comments: 31762
However, temperatures here at the weekend are set to plummet.

Saturday will have temperatures feeling like around 17F (-8C), with Scotland likely to be even colder. Heavy snow and blizzard advisories have been issued from Scotland down to East Anglia. Gusts were mooted to reach around 70mph.

"Blizzards & Heavy Snow Sat 22 Nov

There is a moderate risk of a severe weather event affecting parts of northern and eastern Scotland and many eastern coastal areas of England. Heavy snow showers will bring accumulations of several cms in places, especially in the north and over hills, where strong winds will also give blizzard conditions at times.

Issued at: 1008 Wed 19 Nov"
Member Since: August 23, 2008 Posts: 7 Comments: 5300
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always 72 inside!


LOL - good answer.
Member Since: September 2, 2008 Posts: 96 Comments: 31762
504. Cotillion

Not complaining, it will probably warm to mid 60s pretty quick today. Should be fairly nice depending on what the winds do.
Member Since: September 2, 2008 Posts: 96 Comments: 31762
Quoting RobDaHood:
503. MissNadia

Hi! You're about due for some calm sunny weather. Sorry about the cold.
Going to be cold and sunny all week!!....no problem... always 72 inside!
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Good morning, Cotillion!

What's going on?
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503. MissNadia

Hi! You're about due for some calm sunny weather. Sorry about the cold.
Member Since: September 2, 2008 Posts: 96 Comments: 31762
Quoting sullivanweather:
Down to 16°F here this morning. The lake in the backyard has frozen over. Winter is here...


Hey Sully, Rob.

As someone adequately put, the Hot Cocoa warnings are definitely up over there!

Here, it's about 50, which isn't too bad.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Good Morning Rob
28 Deg here .. coldest day in 2008 so far... no wind and clear skies !
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Down to 16°F here this morning. The lake in the backyard has frozen over. Winter is here...
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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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