Apple Fire (2020): mapping the 33,424-acre footprint

The archived outline of the Apple Fire spans about 18.6 km from west to east and 12.9 km from south to north. CAL FIRE places the incident at off of Oak Glen Road and Apple Tree Lane, North of Cherry Valley. The mapped boundary provides a second way to locate the event: it shows the extent around that reference location.

Start listed by CAL FIRE31 July 2020
County listingRiverside
Reported area in hectares13,526 ha (converted from acres)
Extent of the mapped outline18.6 × 12.9 km (west–east × south–north)
Perimeter collection method as recordedGPS – Uncorrected Data
Apple Fire historical perimeter; north up. Approximate spans 18.6 by 12.9 kilometres.
Generalized historical perimeter. Source: NIFC interagency fire perimeter history.

What the perimeter shows

The two spans differ by only 5.7 km. That does not make this a circular burn: the dimensions measure the outermost coordinates, leaving indentations and gaps invisible. Use the polygon itself, rather than its enclosing rectangle, to check whether a location intersects the footprint.

Two estimates of area

The incident report gives 33,424 acres; the interagency feature stores 33,235.8 GIS acres. The mapped value is 188.2 acres below the reported value (0.56%). This compares two published measurements, not two observation times. The difference cannot be read as fire growth.

CAL FIRE also records structures destroyed: 13. Those counts come from the incident record. A building inside the perimeter cannot be assigned a damage category from this map alone.

A similar-sized fire for comparison

The Gap Fire of 2016 is the closest match by reported acreage in this 100-case collection (33,867 acres). Its mapped spans are 15.8 by 17.3 km, west–east then south–north, versus 18.6 by 12.9 km here. The longer axes run in different directions. Matching on acreage would miss that contrast.

Sources and map method

Spans use the geographic extremes of a generalized boundary, converted to kilometres at its middle latitude. They are approximate map dimensions, not distances travelled by flames. The GIS acreage is the source attribute, not an area recalculated from the simplified outline.