Plot Accumulated Snow Points on Snowfall Map

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Canuck64
Posts: 28
Joined: Tue Sep 04, 2012 10:41 pm
Contact:

Plot Accumulated Snow Points on Snowfall Map

Post by Canuck64 » Sat Sep 24, 2016 6:58 pm

Hi,

I'm trying to plot point snowfall accumulation values based on locations I define in a script. The script I use is a heavily modified Leins script, and the formula for plotting the point values is based on a previous posting to this list in regards to plotting point temperatures. I was hoping I could use this in plotting accumulated snowfall point values.

Here is part of my script to show what I'm doing:

########## Accumulated Snow Total ##########
######
###### Uses 10:1 liquid to snow ratio ######
##
## *** I M P O R T A N T ***
## must accumulate snow total via a loop, as the
## WRF 3.7.1.x no longer outputs snow totals directly
##
say 'starting accumulated snowfall production'
'set grads off'
'set gxout shaded'
#'snow_total_color.gs'
'snow100.gs'
if (count >= 1)
'define snowtotal=sum(ASNOWsfc.1, t=1, t='dis_t-freq')'
else
'define snowtotal=0'
endif

'd snowtotal'

# Plot point snowfall accumulation

# Pittsburgh
***First query to get x,y from lat/lon:
lon = -79.99
lat = 40.44
'q w2xy 'lon' 'lat
x = subwrd(result,3)
y = subwrd(result,6)
***Second query to get snow accumulation at i,j rather than x,y:
'q w2gr 'lon' 'lat
x2 = subwrd(result,3)
y2 = subwrd(result,6)
if (count2 >= 1)
'define snowtotal2=sum(ASNOWsfc.1, t=1, t='dis_t-freq')'
else
'define snowtotal2=0'
endif
'd snowtotal2'
***Query (defval) value of snow accum at i,j
'q defval snowtotal2 'x2' 'y2
snowaccum = subwrd(result,3)
**Round snowfall accum value:
snowaccum = math_nint(snowaccum)
'draw string 'x' 'y' 'snowaccum
#
# Plot every 5 for color bar
'run cbarnskip.gs 5 0.75 1'

The map looks like this, however the point snowfall accumulated value is not being displayed for Pittsburgh.

http://www.goldenhorseshoewx.ca/images2 ... 27_syn.png

Canuck64
Posts: 28
Joined: Tue Sep 04, 2012 10:41 pm
Contact:

Re: Plot Accumulated Snow Points on Snowfall Map

Post by Canuck64 » Thu Oct 06, 2016 9:04 pm

I now have the accumulated snowfall points now plotting on my map.

This is the code snippet:

########## Accumulated Snow Total ##########
######
###### Uses 10:1 liquid to snow ratio ######
##
## *** I M P O R T A N T ***
## must accumulate snow total via a loop, as the
## WRF 3.7.1.x no longer outputs snow totals directly
##

say 'starting accumulated snowfall production'
'set grads off'
'set gxout shaded'
'define snowtotal=sum(ASNOWsfc, t=1, t='dis_t')'
'snow100.gs'
'd snowtotal'

# Beginning of point plots of snow accumulation values
'set strsiz 0.08'
'set string 1 c 6'

# Hamilton
***First query to get x,y from lat/lon:
lon = -79.93
lat = 43.17
'q w2xy 'lon' 'lat
x = subwrd(result,3)
y = subwrd(result,6)
***Second query to get temp at i,j rather than x,y:
'q w2gr 'lon' 'lat
x2 = subwrd(result,3)
y2 = subwrd(result,6)
# Don't need to define a parameter here... As some do.
***Query (defval) value of snowfall at i,j
'q defval snowtotal 'x2' 'y2
snowa2 = subwrd(result,3)
**Round snowfall value:
snowa2 = math_nint(snowa2)
'draw string 'x' 'y' 'snowa2
#
# London
***First query to get x,y from lat/lon:
lon = -81.15
lat = 43.03
'q w2xy 'lon' 'lat
x = subwrd(result,3)
y = subwrd(result,6)
***Second query to get temp at i,j rather than x,y:
'q w2gr 'lon' 'lat
x2 = subwrd(result,3)
y2 = subwrd(result,6)
# Don't need to define a parameter here... As some do.
***Query (defval) value of snowfall at i,j
'q defval snowtotal 'x2' 'y2
snowa2 = subwrd(result,3)
**Round snowfall value:
snowa2 = math_nint(snowa2)
'draw string 'x' 'y' 'snowa2
#
(Here, one would add the cbarnskip in order to plot the colorbar.

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