diff --git a/lib/weewx_proxy/http/ecowitt.ex b/lib/weewx_proxy/http/ecowitt.ex
index 5c26b5b..002a261 100644
--- a/lib/weewx_proxy/http/ecowitt.ex
+++ b/lib/weewx_proxy/http/ecowitt.ex
@@ -24,7 +24,15 @@ defmodule WeewxProxy.HTTP.Ecowitt do
         _ = Logger.debug("Removing keys: `#{inspect(sdr_keys)}'")
         partial_data = Map.drop(data, sdr_keys)
         :ok = Publisher.publish("weewx/ingest_us", partial_data)
-        Publisher.publish_value_map("hadata/weewx/us", partial_data)
+        :ok = Publisher.publish_value_map("hadata/weewx/us", partial_data)
+
+        hadata_si = convert_data_ha(partial_data)
+
+        if map_size(hadata_si) > 0 do
+          Publisher.publish_value_map("hadata/weewx/si", hadata_si)
+        else
+          :ok
+        end
       else
         _ = Logger.error("Not publishing record because data appears invalid: #{inspect(data)}")
         :ok
@@ -121,4 +129,17 @@ defmodule WeewxProxy.HTTP.Ecowitt do
   defp valid_data?(data) do
     Map.has_key?(data, :outTemp) and is_number(data.outTemp)
   end
+
+  @spec convert_data_ha(map()) :: map()
+  defp convert_data_ha(data) do
+    result = %{}
+
+    result = if Map.has_key?(data, :outTemp), do: Map.put(result, :outTemp, (data.outTemp - 32.0) / 1.8), else: result
+    result = if Map.has_key?(data, :outHumidity), do: Map.put(result, :outHumidity, data.outHumidity), else: result
+
+    result = if Map.has_key?(data, :inTemp), do: Map.put(result, :inTemp, (data.inTemp - 32.0) / 1.8), else: result
+    result = if Map.has_key?(data, :inHumidity), do: Map.put(result, :inHumidity, data.inHumidity), else: result
+
+    result
+  end
 end