new_ua_temp_colormaps (#251)

* new_ua_temp_colormaps
These are some requested changes in the 925mb, 850mb, 700mb, and 500mb temperature contours, to clearly delineate the 0 deg line and provide more clarity in the -5 to +5 C range.  The 500mb scale was changed to match the scales at the other levels.

* Reinstated old t_colors (which is now only used with potential temp) and made a new routine, ua_temp_colors.  Passes local pylint and pytest.

adb_graphics/default_specs.yml

@@ -1674,9 +1674,9 @@ temp: # Temperature
     unit: F
     wind: 10m
   500mb: &ua_temp
-    clevs: !!python/object/apply:numpy.arange [-70, 10, 2.5]
+    clevs: !!python/object/apply:numpy.arange [-40, 40, 2.5]
     cmap: jet
-    colors: t_colors
+    colors: ua_temp_colors
     contours:
       pres_sfc:
         levels: [0, 500]
@@ -1697,7 +1697,6 @@ temp: # Temperature
     wind: True
   700mb:
     <<: *ua_temp
-    clevs: !!python/object/apply:numpy.arange [-40, 40, 2.5]
     contours:
       pres_sfc:
         colors: 'k'
@@ -1711,7 +1710,6 @@ temp: # Temperature
         levels: [0, 700]
   850mb:
     <<: *ua_temp
-    clevs: !!python/object/apply:numpy.arange [-40, 40, 2.5]
     contours:
       pres_sfc:
         colors: 'k'
@@ -1723,7 +1721,6 @@ temp: # Temperature
         levels: [0, 850]
   925mb:
     <<: *ua_temp
-    clevs: !!python/object/apply:numpy.arange [-40, 40, 2.5]
     contours:
       pres_sfc:
         colors: 'k'

adb_graphics/specs.py

@@ -474,7 +474,7 @@ def soilw_colors(self) -> np.ndarray:
     @property
     def t_colors(self) -> np.ndarray:
 
-        ''' Default color map for Upper-Air Temperature '''
+        ''' Default color map for Potential Temperature '''
 
         ncolors = len(self.clevs)
         return cm.get_cmap(self.vspec.get('cmap', 'jet'), ncolors)(range(ncolors))
@@ -499,6 +499,18 @@ def terrain_colors(self) -> np.ndarray:
                     (range(54, 157, 6))
         return ctable
 
+    @property
+    def ua_temp_colors(self) -> np.ndarray:
+
+        ''' Default color map for Upper-Air Temperature '''
+
+        grays = cm.get_cmap('Greys', 27)(range(17, 1, -2))
+        purples = cm.get_cmap('Purples', 27)(range(17, 1, -2))
+        ncar = cm.get_cmap(self.vspec.get('cmap'), 128) \
+                          ([30, 34, 36, 40, 45, 55, 60, 65, 70, \
+                          75, 80, 85, 90, 95, 100, 115])
+        return np.concatenate((grays, purples, ncar))
+
     @property
     def vis_colors(self) -> np.ndarray: