External humidity 1% overnight?

[Jonzjob]

Just recently the external humidity on my Vantage Vue has been showing 1% first thing in the morning. This morning it is quite foggy. Other mornings it has been chucking it down with rain and it still shows 1%. It ain't rocket svience to know that it should show more, so has anyone any idea why this is happening please.

 

I changed the battery in the external unit a couple of months back. Just as well that it's fairly accessible or the thing would have gone by now because of the need to change that battery.

[Mapantz]

The sensor is kaput.

When the temp/humidity sensor starts failing on the Davis Vantage Pro2, the same thing happens - humidity readings go pear shaped.