On the MODIS front, there is good news and bad news if you’re in Cachagua:
The good news is that there was no new heat found at all near the General Store:
The bad news is that the south-central portion of the fire continues to move east:
All but one of the new hotspots is on the low end of the radiant power scale:
[VIIRS added 2100]
Pretty amazing VIIRS data from today. Only three new hot spots. You’ll find it hard to see them, so I’ve drawn some arrows in:
Let’s not count our chickens, but this is the best I’ve seen the satellite data since the fire started.
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.
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