Tuesday, July 25, 2006

Horse Fire IX

Just when you think it’s safe to get a good night of unworried sleep, this darned fire jumps up and slaps you upside the head. A couple of hours ago, everything I could find out sounded like this fire was on its way down.

Now I’m not so sure.

The top map is zoomed out to show the entire fire, with satellite data that’s current as of 6 PM. The green splotch is where our home is. The purple splotch south of the west flank of the fire is a lookout point that we drove to at about 5 PM. To the north and slightly east of that vantage point, I’ve shaded in blue the places where we saw some open flames — not a huge blaze, mind you; more like a collection of bonfires a few hundred feet apart.

The MODIS data (see earlier posts for an explanation of how this data is gathered) shows active spots to the west of Lyons Valley Road for the first time. This is worrisome for us, as it indicates the fire is still burning its way toward us. As we expected, there is activity on MODIS all around the north half of Barrett Lake, and out toward Lake Morena.

The center map, directly at right, shows the same data but zoomed in to show just where our home is and that worrisome western flank of the fire. Again, the green splotch is where our home is, and the blue shaded area is where we saw flames at 5 PM. Those two red MODIS splotches closest to our home is what will keep me from sleeping well tonight…

I called the CDF info line again, and learned that they’re still estimating the burned area at 15,400 acres and just 5% contained. My own estimate, from the satellite data, is that 33 to 39 square miles (22,000 to 25,000 acres) have burned. CDF is reporting lots of assets on the fire: 1,164 people, 17 fire crews, 176 engines, 6 air tankers, 6 helicopters, 6 bulldozers, and 13 water tenders. They also say that the hot, dry weather and rugged terrain are hampering their efforts — of this I have no doubt. But it would be ever so much worse if we had bad winds, and thank goodness we do not.

The bottom map is one I have not posted about before. This is the raw WF-HMS data from NOAA. On this map, our home is the blue dot. Their mapping system is not as sophisticated as the one I’ve been showing you maps from, as you can see from cartoonish presentation. One thing that’s particularly confusing is that they use a different map projection system, which has the result that their map appears to be sort of twisted in a clockwise direction by about 20 degrees from the maps you’ve been seeing. Nevertheless, it shows more current WF-HMS data, and it has something in addition: it shows the smoke pattern observed by satellite. And in the case of the Horse Fire, you can easily see that the high-level smoke is moving off mostly to the north.

This will likely be my last post for the evening, unless something dramatic happens. The temperature is cooling off rapidly (75F right now) and the humidity is rising just as quickly (36% right now) — both very good things for the firefighters.

And we are certainly wishing those firefighters well tonight…

Horse Fire IX

The Aqua (EOS PM) satellite, one of those carrying the MODIS imaging equipment, made a pass overhead just before 3 PM. Its view of our area was fairly oblique, as it passed way to the west of us…so the western flanks of the fire may have been invisible to it, as well as anything burning deep in Secret Canyon. It does show a broad area that’s very hot, near the western side of Lake Morena — the furthest part of the Horse Fire from our home…

The darned CDF information line is a bit like playing the slots. Most of the time you just get an old recording. If you’re lucky, you get a human, but they don’t really know very much. If you hit the jackpot — and I just did — you get a human who is well-informed. And even had a sense of humor!

From my jackpot CDF lady I got a good verbal report of the areas still burning (I’ve hand-shaded these purple on the map). The one of most concern to us is the western flank of the fire, and she described an area that jibes nicely with what the survey crew told us. It’s still not an immediate concern for us. She also told us where it’s burning in Secret Canyon; that’s the northernmost purple splotch. It’s also burning on the north and east sides of Lake Barrett — but the honor camp (for dishonorable people) is still safe. And finally, the major burn area is in Bobcat Meadows, just west of the northernmost part of Lake Morena — this jibes nicely with the MODIS data.

The eastern flank of the fire — out near Lake Morena — is still in a wilderness area, but getting closer to civilized areas. I hope they can stop it before it passes Lake Morena, headed east…

Horse Fire VIII

Around 12:30 PM this afternoon we saw a quickly growing column of white smoke suddenly pop up from behind Gaskill Peak (as seen from our yard). The CDF information number was back on a recorder (with a four hour old message), and there’s been no new satellite info since 7AM. We were worried, so we decided to do another reconnoiter.

On Sunday evening, the last time we did a reconnoiter, we made it to a roadblock at the red line on the map at right. From there, we had a great view of the valley that Barrett Lake is in, and north to Horsethief and Secret Canyons, where the fire was burning. This afternoon we only made it to the purple line, where a new roadblock was installed. My theory is that the CDF is using Lyons Valley Road for helicopter operations; my evidence is that we saw four fuel trucks leaving.

Our home is in the green splotch. The blue line is roughly the ridgeline that lies between us and the fire. We’re very fond of the ridgeline — not only is it a beautiful view from our home, but it’s also a very defensible line for the fire-fighters, should the fire start burning west of Lyons Valley Road.

On the way down Skyline Truck Trail, and on the part of Lyons Valley Road that we could drive, we saw helicopters very low overhead, and fuel trucks parked at several locations — probably staged for quick use when needed.

Right at the roadblock, we saw a CDF survey team pickup parked, with one crewmember trying to open the locked gate. I took advantage of the moment to talk with the driver, who was very informative. From her we learned:

— The Carveacre voluntary evacuations were ordered because the community is so difficult to evacuate, with just one twisty, steep dirt road for access. It’s not that Carveacre is immediately threatened.

— The fire is still entirely east of Lyons Valley Road. She gave us a good verbal description of where it’s burning on the western flank of the fire; I’ve shaded that area in yellow on the map.

— She confirmed that the CDF was making a stand on Lyons Valley Road, and had the objective of keeping the fire on the eastern side of it.

— She told us that all the ridgetops (being defensible and accessible to the planes) were being “painted” with fire retardant.

Then her crewmate got the gate open, and they took off to do some reconnoitering of their own. As we walked back to our car, we saw the most amazingly stupid thing I’ve seen in quite a while. A pair of cars was stopped in the middle of the road, with the two drivers talking to each other through their open windows. The road was narrow in this area, so they completely blocked it. Behind them was a line of 7 firefighting vehicles, trying to get out of the Skye Valley area (near Lake Barrett), including fuel trucks, crew operations trucks, and a helicopter logistics truck. These two idiots sat there with all this equipment held up behind them, just jabbering away. When I hollered over at them that they were gumming up the works, one of the drivers answered back with a rude comment about my ancestry. But they moved, finally.

Just before we pulled out to head back home, I took a good look at the visible smoke plumes. The biggest one, by far, seemed to be coming from further east, out toward Lake Morena. The closer in burn area, on the western flank and most concerning to us, showed much less smoke. We took some comfort from that…

Horse Fire VII

Several of my readers have emailed to ask me how on earth I could possibly see anything good coming out of the Horse Fire. One of them (who shall remain unnamed) even accused me of being around-the-bend insane. This is an attempt to defend my sanity.

These maps show a larger area than the recent maps I’ve published. In both of these, there’s a purple square in the area where our home is, just to the left of center.

The upper map has pinkish areas that show all the areas burned in fires that occurred from 2000 through 2005. Those pink areas are the least likely to burn again within the next few years, because much of the fuel is gone. I’ve driven through those pink areas to the northwest of our home within the past few weeks — and even though that fire was in 2001, five years ago, there’s still very little fuel there.

But if you start with that purple square, and look at the 90 degree swath of land from about NE to about SE, you’ll see that there’s virtually nothing that’s burned within the past six years — for miles and miles and miles. During a Santa Ana wind condition, that’s the direction the winds are coming from — so any fire that started out in that direction during a Santa Ana would pose a big risk to us.

Now if you look at what the Horse Fire has done, you’ll see that it has reduced the aperture of risk considerably. Any fire starting to the east of the Horse Fire’s area will have to go around that burned area to get us. It’s still not impossible for it to do so, of course — but it’s definitely going to slow such a fire down, and remove a whole bunch of fuel that could have made it grow.

The lower map (at right) shows different green shadings for fires in the decades between 1950 and 1999. Most of that map is covered by an area burned in 1972. All of Lawson Valley, including where our house now stands, was burned that year. We’re living amidst 34 years of fuel accumulation — and that’s the same kind of accumulation that the Horse Fire is now burning in.

The most relevant thing visible on this map is due south of the Horse Fire, where there’s an area of about the same size as the fire that isn’t burned on either of these two maps. That means that there’s over 50 years of fuel accumulated in that area — making it the biggest risk area left anywhere near our home. Between that area and our home, very little has burned since 1972. If any fires pop up in that area, you can bet we’re going to be watching closely and biting our fingernails…

Horse Fire VI

Just got off the phone with a real person at CDF, instead of the recording they’ve been using. This person, who seemed to actually have some sense of what was really going on, gave me several pieces of useful information:

— Winds on the scene are light, erratic, and not a problem.

— The fire has not (yet) crossed west of Lyons Valley Road. This is the last road between the fire and Lawson Valley, where we live.

— Primary fire activity currently is near Lake Morena and on the east side of Barrett Lake.

— Wind forecast is for moderate winds to the northeast. This is good for us, bad for Guatay/Pine Valley.

Horse Fire V

Acrid smoke in the air this morning — smells very strongly, with an acidic bite. It’s reminiscent of the Cedar Fire three years ago; not a pleasant memory.

The map at right was current as of 6 AM this morning. I’ve had some questions about the satellite data and exactly what it’s showing. Here’s what I understand after some research last night and this morning.

The MODIS data shows up as one kilometer (about 0.6 miles) diameter circles with slanted line shading in them. Where there’s a circle, the satellite detected heat. The heat measurement is integrated over the entire one kilometer circular area — so a pinpoint of extremely intense heat could trigger it, and so could a broad area of much lesser heat. It does not necessarily mean fire — but it probably indicates at least some fire somewhere in that circle. The colors of the splotches indicate their age. Red splotches are less than 12 hours old; orange splotches are 12 to 24 hours old, and black splotches are more than 24 hours old.

The WF-HMS data is much different. This is data generated by the NOAA as a result of a human analyst who is looking at several different sources of data. The data available to the analyst includes MODIS, visible light imagery, smoke plume detection, and more. The analyst then makes an estimation of where actual fires are, placing dots on a 250 meter grid to indicate them. They’re visible on this map as relatively small solid red dots. The red dots are less than 24 hours old; if there were any data 24 to 48 hours old, they’d show up as yellow dots.

I’ve hand-drawn a few features on the map:

The green splotch at left is the area where our home is.

The purple arrow points to a purple dot; that’s where we stood on Sunday evening when we reconnoitered the fire. Just above and to the right of that purple dot, you can see one of the small red WF-HMS dots (just to the right of the black line that indicates Lyons Valley Road).

The blue horseshoe shaped line (open to the left) is the approximate ridge line of the line of mountains that forms Lawson Valley (where we live). The fire is on the other side of that ridge from us. This matters because ridgelines form naturally defensible lines for the firefighters — fire moves much more easily up a slope than it does down a slope, and the ridge makes and easy target for the aerial tankers. Having a very defensible line between us and the fire is a very good thing that we are taking some comfort from.

The large yellow shaded area at top and toward the left (west) is the community of Carveacre. There has been a voluntary evacuation of Carveacre for most of the past 48 hours, and we’re still trying to figure out why. The fact that the CDF has the evacuation in place is worrisome, as the community of Carveacre is (as you can see) quite close to us.

I just listened to the latest CDF report, and its a real eye-opener. First thing: they’re now reporting 15,500 acres consumed, which is very close to the estimate I made yesterday from the satellite data. There’s a lesson there: the CDF reports are not current. CDF is now reporting a lot more assets on the fire: 770 firefighters, 102 fire trucks, 8 bulldozers, 7 helicopters, and 6 aerial tanker planes. They’re still reporting just 5% containment, which probably mainly reflects the fact that the fire is mostly burning in remote wilderness areas.

The CDF also reports that with the evening, the actively burning areas are much diminished — but with the heat of the day, they expect strong flareups in three areas: Secret Canyon (the part burning to the northeast toward Pine Valley and Guatay), Hauser Canyon (the part burning to the east, and nearing the western edge of Lake Morena), and (most worrisome to us) the part burning on all sides of the northern half of Lake Barett. The latter part is four to five miles away from our home; it’s the area I took pictures of on Sunday.

As I prepared this post (and after I prepared the map at right), there was another satellite update. The MODIS data is largely unchanged.