Hi Ryan!
There are a couple of directions you can go. As far as I know, there is not
lat/lon grid available in the nexrad files. However, you do have the
lat/lon of the radar itself. From there you can use that point to generate
the lat/lons from your x and y variables using pyproj. The x and y
variables are essentially in azimuthal equidistant projection so you could
use something like,
def get_lonlat(x,y):
from pyproj import Proj
p = Proj(proj=‘aeqd', ellps='sphere',
lon_0=nexrad_lon,
lat_0=nexrad_lat)
return p(x,y,inverse=True)
all you have to do is plug in the proper lon/lat value from the nexrad
file, then feed it the x and y values and it will return two arrays. The
call in a notebook might be
lon, lat = get_lon_lat(xlocs,ylocs)
Alternatively, you could use pyart, which now has the capability to plot
using Cartopy
http://arm-doe.github.io/pyart/dev/user_reference/generated/pyart.graph.RadarMapDisplayCartopy.html#pyart.graph.RadarMapDisplayCartopy
Easy install for pyart
conda install -c conda_forge arm_pyart
-Kevin
On 25 April 2017 at 8:05:35 AM, Ryan Connelly (rconne01@xxxxxxxxx) wrote:
Hi,
Using this code:
https://unidata.github.io/MetPy/examples/formats/NEXRAD_Level_2_File.html#sphx-glr-examples-formats-nexrad-level-2-file-py
Ideally, I should be able to just extract a lat and a lon variable from the
file, except that I don't know if they exist, and if they do, what their
names are.
>From there, I'd like to plot the georeferenced data over a base map using
CartoPy. Is this possible? (I just happen to already have some shapefiles
on hand that I want to use that I know CartoPy can read in.)
Thanks,
Ryan
--
Ryan Connelly
M.S. Student in Atmospheric Sciences, Stony Brook University
B.S. in Meteorology with Minors in Mathematics and GIS, Valparaiso
University
rconne01@xxxxxxxxx
ryan.connelly@xxxxxxxxxxxxxx
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