diff --git a/wunderground.c b/wunderground.c
index c64a3b1..7d754fb 100644
--- a/wunderground.c
+++ b/wunderground.c
@@ -5,6 +5,9 @@
 #include <stdio.h>
 #include <string.h>
 #include <math.h>
+#include <time.h>
+#include <locale.h>
+#include <stdlib.h>
 #include "wunderground.h"
 
 // file that contains weather underground station ID (first line) and
@@ -20,16 +23,102 @@
 // maximum command length
 #define CMDLENGTH 1024
 
+// number of samples of data per hour
+// = 3600 seconds / 48 seconds
+#define SAMPLESPERHOUR 75
+
 // module variables
 static char gStationId[STATIONIDLENGTH];
 static char gPassword[PASSWORDLENGTH];
 
+static int CurrentDay = -1;
+static double RainatStartofDay = 0.0;
+
+// keeps track of rain over the last hour
+static int CurrentRainSample = -1;
+static double LastRainSample = 0.0;
+static double RainSamples[SAMPLESPERHOUR];
+
+// gets rain in the last hour in mm
+static double GetHourlyRainTotal
+  (
+  double TotalRain
+  )
+{
+  int i;
+  double Total;
+
+  // no samples yet so initialize
+  if (CurrentRainSample == -1)
+  {
+    LastRainSample = TotalRain;
+    CurrentRainSample = 0;
+    return 0.0;
+  }
+
+  // get new rainfail
+  double NewRain = TotalRain - LastRainSample;
+  LastRainSample = TotalRain;
+
+  // store sample in circular buffer
+  RainSamples[CurrentRainSample] = NewRain;
+  CurrentRainSample++;
+  if (CurrentRainSample == SAMPLESPERHOUR) CurrentRainSample = 0;
+
+  // get total rain in last hour
+  Total = 0.0;
+  for (i = 0; i < SAMPLESPERHOUR; i++) Total += RainSamples[i];
+
+  return Total;
+}
+
+// gets the total amount of rain for today in mm
+static double GetDailyRainTotal
+  (
+  double TotalRain                    // total rain value from station
+  )
+{
+  // get local time
+  time_t t = time(NULL);
+  struct tm *now = localtime(&t);
+
+  // no daily rain information, so start anew
+  if (CurrentDay == -1)
+  {
+    CurrentDay = now->tm_yday;
+    RainatStartofDay = TotalRain;
+    return 0.0;
+  }
+
+  // day has changed, start anew
+  if (CurrentDay != now->tm_yday)
+  {
+    CurrentDay = now->tm_yday;
+    RainatStartofDay = TotalRain;
+    return 0.0;
+  }
+
+  // same day so get total rain since start of day
+  double RainToday = TotalRain - RainatStartofDay;
+
+  // if negative value then transmitter batteries were changed
+  if (RainToday < 0.0)
+  {
+    RainatStartofDay = TotalRain;
+    return 0.0;
+  }
+
+  return RainToday;
+}
+
 // initializes the module
 void WUnderground_Init
   (
   void
   )
 {
+  int i;
+
   // read in credentials
   FILE *fp = fopen(CREDENTIALS, "r");
   fgets(gStationId, STATIONIDLENGTH, fp);
@@ -37,6 +126,9 @@
   fgets(gPassword,  PASSWORDLENGTH,  fp);
   strtok(gPassword, "\n");
   fclose(fp);
+
+  // no rain data
+  for (i = 0; i < SAMPLESPERHOUR; i++) RainSamples[i] = 0.0;
 }
 
 // submits an observation
@@ -52,7 +144,11 @@
   )
 {
   char Cmd[CMDLENGTH];
-  char UTCTimestamp[20];
+  char UTCTimestamp[40];
+
+  // get timestamp
+  time_t now = time(NULL);
+  strftime(UTCTimestamp, 40, "%Y-%m-%d+%H%%3A%M%%3A%S", gmtime(&now));
 
   // get temperature in F
   double TemperatureF = (TemperatureC * 9.0 / 5.0) + 32.0;
@@ -83,9 +179,12 @@
   else if (!strcmp(WindDirection, "NW"))  WindDegrees = 315;
   else if (!strcmp(WindDirection, "NNW")) WindDegrees = 337.5;
 
-  strcpy(UTCTimestamp, "timestampgoeshere");
+  // get amount of rain today in mm
+  double RainToday = GetDailyRainTotal(TotalRainMm);
+  // get amount of rain in last hour in mm
+  double RainLastHour = GetHourlyRainTotal(TotalRainMm);
 
-  sprintf(Cmd, "wget -b -a /tmp/wunderground.log -O /tmp/wunderground-result.html \"%s?action=updateraw&ID=%s&PASSWORD=%s&realtime=1&rtfreq=48&dateutc=%s&tempf=%f&humidity=%f&windspeedmph=%f&windgustmph=%f&baromin=%f,&dewptf=%f&winddir=%.1f\"",
+  sprintf(Cmd, "wget -b -a /tmp/wunderground.log -O /tmp/wunderground-result.html \"%s?action=updateraw&ID=%s&PASSWORD=%s&realtime=1&rtfreq=48&dateutc=%s&tempf=%f&humidity=%f&windspeedmph=%f&windgustmph=%f&baromin=%f,&dewptf=%f&winddir=%.1f&dailyrainin=%f&rainin=%f\"",
     WUURL,
     gStationId,
     gPassword,
@@ -96,8 +195,11 @@
     WindGustMph,
     PressureHpa * 0.0295299830714,
     DewPointF,
-    WindDegrees
+    WindDegrees,
+    RainToday * 0.0393701,
+    RainLastHour * 0.0393701
     );
 
   printf("%s\n", Cmd);
+  system(Cmd);
 }