[0900: VIIRS data added below.]
The news is unequivocally good.
First, the Cal Fire fire perimeter data for last night and the night before, overlaid on each other.
Zooming in on the west, where things looked pretty exciting — and not in a good way — yesterday morning, we can see that Cal Fire recognizes the heat on the wrong side of the fire line that we saw with the VIIRS data yesterday, but it’s not so widespread:
In the Cachagua area, though what is probably a combination of some back burning and wild fire moving into areas that had been extensively back burned over the past few days, the triangular gap has been filled in. There is also a large advance towards the southeast:
Here’s the aerial infrared data from last night. Note the legend in the upper left corner. The colors on the map are somewhat muted from those in the legend because the infrared overlay is partially transparent to let the earth’s features show through:
In the west, the areas of intense heat on the wrong side of the fire line are broader than indicated in the Cal Fire perimeter map. The heat pattern along the north side of the southern fire line is one that indicates back burning:
Over by Cachagua, you can see that the area on the Cal Fire map that was indicated as completely filled in is not quite that way:
Here’s the MODIS data from last night:
There are a few hot spots on the north side of the fire line that is protecting the village of Big Sur. The central region of the fire is moving west, after a few days of moving east. It is about to urn into country that has already been burned in this fire. Such areas can burn again, but usually the second time around is less intense:
Near Cachagua, the satellites didn’t see any new hot spots at all:
The data from the 0330 PDT VIIRS pass is so good the I at first didn’t believe it. but I checked the JPEG image on the web, and it’s right; no new fire detections:
The orange lines are the dozer fire breaks that were in as of 7/30, plus one that I added by hand. The pink lines are the ones that were planned as of that date. The fat black lines are the outlines of the fire’s perimeter on the official Cal Fire maps from last night.
How to read the MODIS/VIIRS heat indications: The size of the square represents the nominal margin of error. The fire could be anywhere in the square, not just at the center. Dark red squares were detected less than six hours before the data set was created. Light red squares were detected less than twelve hours before the data set was created. Orange squares were detected less than 24 hours before the data set was created. Yellow squares were detected less than six days before the data set was created. When the squares overlay other objects, the color of the square changes somewhat, but the color of the dot in the middle does not. So look at the dot if you’re uncertain what color the square should be. Since the fire is now over six days old, some of the early detections have dropped off the map. MODIS makes mistakes, sometimes missing outbreaks, and sometime misplacing them outside the nominal margin of error. It is also a snapshot of the activity at the time the satellite is overhead, and will definitely miss flare ups between passes. MODIS can’t tell the difference between wildfires and intentional back burns.
Yesterday’s visible band MODIS image, with no coastal fog for the first time in a long while:
And the MODIS IR/UV image from yesterday, showing a lot of heat in three locations:
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