Just noticed tonight, every window of my house has condensation on the outside? I have never ever seen that before, I assume it is atmospheric? 

I am in southern Hampshire. 

We get this all the time in the conservatory.  Must be you have top notch windows, or your windows arent warm enough, so become colder than the air temp.

My conservatory is the latter, by which it recieves no heating, apart from sunlight, so chills down a lot at night.

No different to how your car does the same with its windows.  

Out of interest - do you have aluminium frames?

Thanks Russ....no plain old UPVC....but it has never happened before and basically rained all day and cleared around dusk. 

I do remember my mother remarking that her windows did that once .

She noticed it when living in Kent a couple of hours before the start of the "Great Storm" of October 1987

At that time I reckoned it was not connected to the wind strength but was connected to the fact that it had been quite a cold day but the temperature rose markedly and suddenly (I think from about 8C to 14C) just before the start of the storm.

My deduction was that the inside of the house was actually colder than the outside temp so the condensation formed "the other way round" to normal on that occasion

Don't think that applies to today, however, so your explanation is probably different to that

It happened when I was an impoverished student. We scarcely ever heated the house, preferring to sit around in the student bar for warmth, and there were one or two occasions when a warm sector came in and there was condensation on the outside of the windows when we got back.

Basically condensation will happen on a surface that is colder than the dew point of the air. Usually enough heat escapes through your windows from inside the house to keep them warm enough for no condensation to form in the outside. (The dewpoint inside the house will be higher so condensation can form inside, if the window is cold enough).

On this occasion we had quite a warm and humid airmass (high dewpoint) but the skies cleared last night which would have allowed rapid radiation cooling of surfaces, including (I assume) your windows.

We quite often get condensation and/or frost around the bottom of the outside of the window facing north.

Brick she'd window with double glazing all ways has condensation when cold.

All clear today.

The new UPVC windows on our extension condense on the outside but the older ones on the rest of the house (also UPVC) don't. I believe it is because the newer ones are better insulated and the outer surface is colder. Nothing to worry about but annoying nonetheless.

Yes, that's exactly the reason. Annoying but think of it as a good sign that you are not wasting much energy!

I think modern double glazing is filled with argon as it kelps keep the heat in, meaning the outer panes cool by radiation andf thererfore mist up.

For the condensation to occur on the outside, as Rob said, the dewpoint must be higher than the surface temperature of the glass. This can happen when air outside suddenly increases in temperature and/or humidity-  the phenomenon was remarked on by Gilbert White- the poorly insulated and heated houses in the 18th C cooled markedly indoors under cold conditions (White referred to subzero indoor conditions) meaning the glass was cold and not heated from within. With glass having slow temperature change rates, a quick change in airmass to a warmer, moister one led to moisture outside.

I'm not sure if this is the same as moisture on a car windscreen- since that seems to happen all the time. I suspect that's a reflection of the fact that the car does not have a compensatory heat source when out of use, and the metal, wide-surface-area of the roof contributes to the overall cooling of the vehicle. The aspect of the glass seems also to have an impact: some mornings, I have dew / frost on some car windows, but less or even none on others.

A charming short poem by Michael Rosen explores the contrast across glass on a cold day.

From The Winter Wind.

From the winter wind

A cold fly

Came to our window

Where we had frozen our noses

And warmed his feet on the glass.

Thank you