GRLevelX placefile generator for risk hazards from NOAA-NWS Storm Prediction Center
This script set gets JSON outlook data from the SPC GIS Convective Outlooks and formats a placefile for GRLevelX software to display outlines of the areas with risk hazards. A mouse-over the line will popup a text tooltip with details about the risk area.
The SPC-placefile.php script is to be accessed by including the website URL in the GRLevelX placefile manager window. There are 'stub' scripts to invoke SPC-placefile.php with various days selected:
- day1.php Selects risk areas for Day 1. (same as invoking
SPC-placefile.php?day=1) - day2.php Selects risk areas for Day 2. (same as invoking
SPC-placefile.php?day=2) - day3.php Selects risk areas for Day 3. (same as invoking
SPC-placefile.php?day=3) - day4.php Selects risk areas for Day 4. (same as invoking
SPC-placefile.php?day=4) - day5.php Selects risk areas for Day 5. (same as invoking
SPC-placefile.php?day=5) - day6.php Selects risk areas for Day 6. (same as invoking
SPC-placefile.php?day=6) - day7.php Selects risk areas for Day 7. (same as invoking
SPC-placefile.php?day=7) - day8.php Selects risk areas for Day 8. (same as invoking
SPC-placefile.php?day=8)
For ease of usage, the above 8 scripts should be the end-point targets for the GRLevelX placefile manager window.
The cache files are named SPC-N.json (N=1..8) and are created/maintained automatically with a default 8 minute cache lifetime.
This script generates a GRLevelX placefile from the cached JSON
file from SPC GIS on demand by a GRLevel3 instance.
If you run the script for debugging in a browser, add ?version=1.5&dpi=96&lat={latitude}&lon={longitude} to
the URL so it knows what to select for display. The output of the script is always text/plain;charset=ISO-8859-1 for the placefile.
Viewing the placefile in a browser will show GRLevel3 comments (lines starting with ';') showing how each alert is handled.
In the GRLevel3 placefile manager window, just add the script URL without a query string -- GRLevel3 will automatically add those based on the current radar site selected.
Additional documentation is in each script for further modification convenience.
Upload the files/directories into a directory under the document root of your website.
(We used 'placefiles' in the examples below)
Then you can test the placefile script by using your browser to go to
https://your.website.com/placefiles/day1.php?version=1.5&dpi=96&lat=37.0&lon=-122.0
If that returns a placefile, then add your placefile URL (minus the URL query string) into the GRLevelX placefile manager window.
# -----------------------------------------------
# Settings
$timeFormat = "d-M-Y g:ia T"; # display format for times
$cacheFilenameTemplate = 'SPC-%s.json'; # store json cache file
$cacheTimeMax = 480; # number of seconds cache is 'fresh'
$doLogging = true;
$doDebug = false; # =true; turn on additional display, may break placefile for GRLevelX
$TZ = "America/Los_Angeles";
$SPCcolors= false; # =true, use JSON 'stroke' color; =false, use built-in colors
$latitude = 37.155;
$longitude = -121.898;
$version = 1.5;
# -----------------------------------------------Please note that the default installation includes $doLogging = true; which enables logging of accesses
to
SPC-placefile-log-{year}-{month}-{day}.txt (UTC date) text files to the installation directory.
These files are useful to help debugging, but you may want to switch them off by specifying $doLogging = false;.
; SPC-placefile.php - V1.00 - 10-Nov-2023 - saratoga-weather.org
; running on PHP 8.2.0
Title: SPC Day 1 Outlook - Fri Nov 10 13:27:18 PST 2023 - PlacefileNation
Refresh: 5
Color: 200 200 255
Font: 1, 11, 1, 'Arial'
Threshold: 999
; cache file 'SPC-1.json' refreshed from https://www.spc.noaa.gov/products/outlook/day1otlk_cat.lyr.geojson
; JSON decode - - No errors
; 1 features found
; using builtin stroke colors
; polygon #0
; type=MultiPolygon
Color: 183 233 193
Line: 4, 0, "SPC Day 1 Outlook - General Thunderstorm Risk 2000"
29.0050330131,-94.591263231441
28.808,-94.9
28.597,-95.134
28.428,-95.489
28.182,-96.044
28.055,-96.147
27.94,-96.427
27.579,-96.796
27.081,-97.017
26.595,-96.876
25.948,-96.749
25.799,-97.075
25.659,-97.23
25.837,-97.68
25.934,-98.218
26.039,-98.509
26.254,-99.103
26.519,-99.357
26.735876493841,-99.457448060305
28,-98.1
29.1,-95.61
29.0050330131,-94.591263231441
End:
; polygon #1
; type=MultiPolygon
Color: 183 233 193
Line: 4, 0, "SPC Day 1 Outlook - General Thunderstorm Risk 2000"
30.000914625093,-86.924182925019
29.878,-87.771
29.863,-88.406
29.714,-88.432
29.394,-88.695
29.249,-88.581
29.022,-88.619
28.691,-88.937
28.63,-89.175
28.577,-89.399
28.693,-89.712
28.916,-89.828
28.755,-90.102
28.711,-90.54
28.711,-90.745
28.732,-91.083
28.733956887596,-91.085819862871
28.733956887596,-91.085819862871
30,-90.3
30.79,-89.3
30.98,-88.27
30.63,-87.28
30.13,-86.95
30.000914625093,-86.924182925019
End:
; polygon #2
; type=MultiPolygon
Color: 183 233 193
Line: 4, 0, "SPC Day 1 Outlook - General Thunderstorm Risk 2000"
46.867344015155,-124.42312443269
46.914,-124.45
47.095,-124.416
47.322,-124.59
47.654,-124.653
47.833,-124.891
48.196,-125.021
48.603,-125.022
48.528,-124.41
48.375,-123.817
48.395,-123.588
48.452,-123.444
48.604,-123.444
48.73,-123.553
48.947,-123.617
49.187,-123.29
49.134,-123.111
49.303,-122.837
49.247,-122.534
49.18,-121.576
49.186263712123,-121.23865436137
48.51,-122.17
47.46,-123.03
47.21,-123.69
46.867344015155,-124.42312443269
End:
Special thanks to Mike Davis, W1ARN of the National Weather Service, Nashville TN office for his inspiration/testing/feedback during development.