Displays radar images from the JMA.

weather.sh

#/bin/sh
mkdir -p /tmp/weather
if [ -n "$1" ]; then
  echo "Deleting old images."
  rm -rf /tmp/weather/*
fi
cd /tmp/weather
SECS=`date "+%s"`
NUM_FRAMES="50"
while [ $NUM_FRAMES -gt 0 ]; do
  # http://www.jma.go.jp/jp/radnowc/imgs/radar/000/201608291335-00.png
  DATE=`date --date="@$((SECS / 300 * 300 - $NUM_FRAMES * 300))" "+%Y%m%d%H%M"`
  echo http://www.jma.go.jp/jp/radnowc/imgs/radar/000/$DATE-00.png | \
    xargs wget --no-clobber --quiet
  NUM_FRAMES=$[$NUM_FRAMES-1]
done
# sudo apt-get install imagemagick
convert -delay 20 -loop 0 *.png animation.gif
# https://www.iterm2.com/documentation-images.html
imgcat animation.gif