Southampton a zero? I don't think that's ever been recorded in September, has it? I presume that's the airport, as the old station in Mayflower Park closed years ago, and the WU station is in the city centre. That said, 3 was recorded there in 1986 and Mayflower Park was by the water.

I suppose it was the shelter that did the damage. We dipped below 2 this morning; grass was white in the dawn light as I cycled to work.

I bet you're right Nick; would be interesting if any amateurs down there had a reading.

Marvellous thing is- we went from below 2 to 17.5 in the sunshine; so April HP that I had another first for September: a blackbird singing and then a woodpigeon joining in, about half an hour ago! 

Topsy turvy.

Now this is interesting - Southampton doesn't appear on the WeatherOnline lists, but does appear on xcweather. It was xcweather's Southampton that was reporting zero this morning.

Incidentally this spell of cold, crisp mornings and warm, sunny afternoons (with low dewpoints) reminds me of the likes of Calgary in the autumn. It's very pleasant!

Absolutely nothing of note here as is the norm these days. Min was 6.7C last night for the second night out of five with a third recording 6.6C. Incredibly tedious and one of the most boring months I can remember.

Once again September looks like passing without any properly cold nights. Lowest so far has been only 3.4C (on Sunday) which makes it the 5th consecutive September to fail to record a temperature below 3C and, apart from 2016, all have been lousy for warmth too. By contrast between 2005 and 2013 readings below 3C were recorded in four Septembers (2005, 2007, 2012 and 2013) with 2009 also recording 3.4C and that was hardly a classic era for crisp autumn weather.

Hard to believe it used to be possible to get air frosts in September even close to the coast. Lowest I’ve seen in the past 14 years was 1.6C in 2012 which is 0.3C warmer than my June record low! 3.0C on 25th August 2014 is actually colder than any September reading since 2013!

That's very close to the all time record low for Northern Ireland in September of -3.2C which was set in 1991. 

got down to 12.8*c last night. Been almost a frost most other nights

Yes- fourth consecutive of 5°C or below. 

-3.4C at Katesbridge last night looks like the lowest temperature ever recorded in Northern Ireland in September judging by the Met Office climate extremes page (have to click around a bit)? 

https://www.metoffice.gov.uk/public/weather/climate-extremes/#?tab=climateExtremes

Other notable lows for September

-2.0C South Newington (Oxfordshire)

-1.8C Sennybridge (Powys)

My Minimum  this morning was 2.3c at 07:14.

Last night was the seventh consecutive here of 5°C or below.

A week earlier, we had 3 close to or above 17 in a row!

Season of mists and mellow muddles!