DWELL Algorithm Examples
DWELL is comprised of a product and composites successive images of a product in time. Moving targets show a "streak" on the display.
The example shown here is for
DWELL applied to PPI products. The last (most
recent) PPI product in the DWELL sequence is
shown below. It shows a squall line in dBZ. The line was moving from East to
West and developing/decaying as it traveled.
dBZ at a Single Time
The following figure below shows a DWELL of the PPI products for the preceding 2 hours. This is useful to show where precipitation has fallen during the DWELL period. The animation shows the expanding field of fallen precipitation and the echo motion.
dBZ
The final figure in the example shows the age of the DWELL data points, that is, the number of minutes since the most recent PPI product in the sequence. The color scale is configured so that blue shows the most recent echoes while red shows the oldest echoes.
The example shows blue on the left (West) where the current echo is located. The red echoes on the right (East) are the older echoes from earlier in the sequence. This is to be expected for general East to West motion. Residual clutter shows a speckled pattern (for example, at 50 km (31.1 mi) to the Northeast).
