Make '' writable by PHP for this script to operate properly.
<pre>
NWS-regional-radar-animate.php - V1.04 - 18-Jan-2022
using 'https://www.aviationweather.gov/radar/plot?region=wmc&type=rala&date=' for query
now='2025-12-07 22:37:54 UTC' page cached='2025-12-07 22:37:54 UTC' (0 seconds ago)
forceRefresh=true
loading ./cache/NWSregion-wmc-rala.txt from
  'https://www.aviationweather.gov/radar/plot?region=wmc&type=rala&date='
curl fetching 'https://www.aviationweather.gov/radar/plot?region=wmc&type=rala&date='
HTTP stats:  RC=308 dest=13.107.213.35 port=443 (from sce=192.135.112.131)
      Times: dns=0.011 conn=0.013 pxfer=0.024 get=0.002 total=0.026 secs
headers returned:
HTTP/2 308 
date: Sun, 07 Dec 2025 22:37:54 GMT
content-length: 0
location: https://aviationweather.gov/radar/plot?region=wmc&type=rala&date=
x-azure-ref: 20251207T223754Z-18496456d97lcvd5hC1BL1wn1400000008b000000000d2gg
x-cache: CONFIG_NOCACHE

unable to open ./cache/NWSregion-wmc-rala.txt for writing 253 bytes.. cache not saved
html loading finished
--Sorry.  Unable to write ./cache/NWSregion-wmc-rala.txt to ''.
</pre>