diff --git a/addons/weather/functions/fnc_calculateHeatIndex.sqf b/addons/weather/functions/fnc_calculateHeatIndex.sqf
index 4605213e24..95060bd0a2 100644
--- a/addons/weather/functions/fnc_calculateHeatIndex.sqf
+++ b/addons/weather/functions/fnc_calculateHeatIndex.sqf
@@ -15,6 +15,16 @@
  */
 #include "script_component.hpp"
 
+#define __C1 -8.784695
+#define __C2 1.61139411
+#define __C3 2.338549
+#define __C4 -0.14611605
+#define __C5 -0.012308094
+#define __C6 -0.016424828
+#define __C7 0.002211732
+#define __C8 0.00072546
+#define __C9 -0.000003582
+
 PARAMS_2(_t,_rh);
 
 _rh = _rh * 100; // relative humidity in %
diff --git a/addons/weather/functions/fnc_calculateWetBulb.sqf b/addons/weather/functions/fnc_calculateWetBulb.sqf
index c044c2ed57..c180cf8384 100644
--- a/addons/weather/functions/fnc_calculateWetBulb.sqf
+++ b/addons/weather/functions/fnc_calculateWetBulb.sqf
@@ -4,7 +4,9 @@
  * Calculates wet bulb based on temperature and relative humidity
  *
  * Arguments:
- *
+ * 0: temperature - degrees celcius <NUMBER>
+ * 1: pressure - hPa <NUMBER>
+ * 2: relativeHumidity - value between 0.0 and 1.0 <NUMBER>
  *
  * Return Value:
  * 0: wet bulb <NUMBER>
@@ -14,6 +16,26 @@
  */
 #include "script_component.hpp"
 
-// TODO: ...
+private ["_es", "_e", "_eDiff", "_eGuessPrev", "_cTempDelta", "_twGuess", "_eguess"];
 
-GVAR(currentTemperature)
+PARAMS_3(_temperature,_pressure,_relativeHumidity);
+
+// Source: http://cosmoquest.org/forum/showthread.php?155366-Calculating-Wet-Bulb-Temperature-from-RH-amp-Dry-Bulb
+_es = 6.112 * exp((17.67 * _temperature) / (_temperature + 243.5));
+_e = _es * _relativeHumidity;
+_eDiff = _es - _e;
+_eGuessPrev = _es;
+_cTempDelta = 3.3145;
+_twGuess = _temperature;
+
+for "_j" from 1 to 50 do {
+    _twGuess = _twGuess - _cTempDelta;
+    _eguess = 6.112 * exp((17.67 * _twGuess) / (_twGuess + 243.5));
+    _eguess = _eguess - (_pressure * (_temperature - _twGuess) * 0.00066 * (1 + (0.00115 * _twGuess)));
+    _eDiff = _eguess - _e;
+    if (abs(_eDiff) <= 0.001) exitWith {};
+    _cTempDelta = _eDiff / ((_eguessprev - _eguess) / _cTempDelta);
+    _eguessprev = _eguess;
+};
+
+_twGuess
diff --git a/addons/weather/script_component.hpp b/addons/weather/script_component.hpp
index bf16255590..edc1ac64d0 100644
--- a/addons/weather/script_component.hpp
+++ b/addons/weather/script_component.hpp
@@ -18,14 +18,3 @@
 #define WATER_VAPOR_MOLAR_MASS 0.018016
 #define DRY_AIR_MOLAR_MASS 0.028964
 #define SPECIFIC_GAS_CONSTANT_DRY_AIR 287.058
-
-// Heat index coefficients
-#define __C1 -8.784695
-#define __C2 1.61139411
-#define __C3 2.338549
-#define __C4 -0.14611605
-#define __C5 -0.012308094
-#define __C6 -0.016424828
-#define __C7 0.002211732
-#define __C8 0.00072546
-#define __C9 -0.000003582