Implement virtual_temp()

lib/xmet/thermo.py

@@ -17,6 +17,17 @@ def kelvin(c: float) -> float:
 def celsius(k: float) -> float:
     return k - 273.15
 
+def virtual_temp(temp: float, dewpoint: float, pressure: float) -> float:
+    a = 7.5 * dewpoint
+    b = 237.3 + dewpoint
+    c = a / b
+
+    d = 6.11 * (10**c)
+    e = d / pressure
+    f = 1 - 0.379 * e
+
+    return celsius((temp + 273.15) / f)
+
 def vapor_pressure(dewpoint: float) -> float:
     """
     Return the pressure, in millibar, of vapor in a parcel of a given