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1/6 I’ve been volunteering to produce online wildland fire maps for about the last 10 years. The #1 thing to know is that any fire data you see on maps is **not real time**. There are 2 MODIS satellites and 2 VIIRS satellites. #GlassFire #GlassIncident #ZoggFire
2/6 The MODIS/VIIRS satellites make a total of 8 passes per 24 hours. For the West Coast very rough timing is midnight to 3am (4 passes) and noon to 3pm (4 passes). It takes NASA ~3 hours to process the raw data before it can be displayed on any map.
3/6 Usually by 7am pacific time the maps are showing all the MODIS/VIIRS data that is available until sometime after 3pm. Hotspot locations are approximate and sometimes the data is ‘false positive’.
