Santa Ana winds ease over Los Angeles
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
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 — Blog Index
As central coastal provinces struggled with the loss of life and the damage caused by storm Noul (Red Sky), questions were being raised about the inaccuracy of forecasts.
Director Bui Van Duc of the National Center for Hydro-meteorological Forecasting (NCHMF) met with local media in Hanoi Tuesday to offer information about recent inaccuracies in the center’s forecasts.
On Sunday, the center had forecast Storm Noul would hit waters off the southern coast Monday and touch down on the mainland in southern provinces a day later.
In late September, the storm Mekkhala had hit north-central provinces hours earlier than forecast by the center.
The torrential rains in Hanoi late October and early this month were also not correctly forecast. The center later warned of more heavy rain and inundation in the area while waters began to recede and recovery work got underway. This did not happen.
We have only one experienced person for each shift of five people,” he said. “Sometimes, they are incompetent in solving problems and besides, there have been instances of carelessness in referring and analyzing information from other sources.
At least seven people were dead or missing and 110 seafaring vessels sunk as Noul hit coastal provinces in central Vietnam on Monday before weakening into a tropical depression, causing torrential rains that are forecast to linger until today
Okay, I got the flu so I can't stop..COME ON. We've sat here & evaluated these storms. Exclaimed look how much rain that thing has. Navy's track has been pretty close to on. Yeah they've had some most impressive cold cloud tops in that region lately but with the internet, floaters, TRMM & what not..to get one wrong one right after another~ about beyond accident. I'm tempted to try & find an e-mail address for Director Bui Van Duc.
(of course I'm sure somebody has already answered this :o)
Viewing: 601 - 602
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 — Blog Index