First Air Frost watch autumn 2013

[damianslaw]

As we move out of summer I thought it would be a good time to hear people's views on when and where they expect to see the first air frosts of the season occur.

 

Clear skies and light/no winds can result in air frosts in sheltered scottish highlands at anytime of year, but the chances compared to July and August increase markedly as we enter September. Altnaharra or Aviemore are usually the first places in the UK to see the first air frost of the new season which I always believes starts in September.

 

I'm not sure when the first air frosts of the new season occured last year, but I remember much of Cumbria saw a heavy air frost on the 22nd September which lingered well into the morning..

 

We don't tend to see our first air frosts until about second week of October and our first ground frost not until the latter third of September.

 

So for Scotland I am going 20th September in Aviemore.

 

England - Redesdale or Shap Fell on the 8th October.

 

 

 

 

[AWD]

The first air frost of the season as a country will probably be in the usual areas of Highland Scotland.

IMBY though, I don't expect to see an air frost until November at the earliest.

[Isolated Frost]

Getting down to 2c I'd expect within the next 2 weeks with current modelling, possibly an isolated air frost or two and plenty of slight ground frosts around, until October kicks in.

 

I'll say either Sennybridge, Shap or Tulloch Bridge; late September.

[Relativistic]

Often get one or two ground frosts here in October, before the first air frosts in November.

As for the entire country, I'll go for 16th September at Dalwhinnie.

[Summer Sun]

If condition's were right the frost could be this weekend in the highlands of Scotland given how low the temperature is shown to get

 

Max temperature

 

 

Lowest temperature

 

[Interitus]

Yes, sooner rather than later I think - it was 1.6°C at Loch Glascarnoch this morning.

[weatherobsuk]

My first ground-frost experience whilst outdoor camping was back in 2005 on September 18th. I was pitched in Morriston near Swansea watching the WRC races, I remember the date vividly due to Michael Parks death during the second stage of the day. For here in the Peak District however I remember 2009 was a exceptional early autumn for both ground and air frosts.

[hillbilly]

As we move out of summer I thought it would be a good time to hear people's views on when and where they expect to see the first air frosts of the season occur.

 

Clear skies and light/no winds can result in air frosts in sheltered scottish highlands at anytime of year, but the chances compared to July and August increase markedly as we enter September. Altnaharra or Aviemore are usually the first places in the UK to see the first air frost of the new season which I always believes starts in September.

 

I'm not sure when the first air frosts of the new season occured last year, but I remember much of Cumbria saw a heavy air frost on the 22nd September which lingered well into the morning..

 

We don't tend to see our first air frosts until about second week of October and our first ground frost not until the latter third of September.

 

So for Scotland I am going 20th September in Aviemore.

 

England - Redesdale or Shap Fell on the 8th October.

Am I not mistaken but I thought Scotland could get an air frost any month of the year....are there not just a hand full of days in the year where there has been no air frost recorded??

[DR(S)NO]

Am I not mistaken but I thought Scotland could get an air frost any month of the year....are there not just a hand full of days in the year where there has been no air frost recorded??

Not quite sure of the answer ...but here is a snippet of onfo from Met Office News Blog talking about August Bank Holiday weather extremes from recent history.Numerous Scottish stations failed to get above 10 °C on Sunday 28th August 2011, the lowest maximum being 9.1 °C at Cromdale. This excludes stations 500 metres above sea level, which may be considerably colder.There have also been numerous instances of air frost over the August Bank Holiday, most of them in Scotland, most notably in 1977 and 1982. The lowest individual reading was -3.1 °C at Kindrogan on Sunday 28 August 1977.

[cheese]

Am I not mistaken but I thought Scotland could get an air frost any month of the year....are there not just a hand full of days in the year where there has been no air frost recorded??

England can too. And Wales. And Northern Ireland.

[A Winter's Tale]

A chilly night here with Glasgow airport recording 4C an hour ago. Down to 3C at Altnaharra so there is a chance of an air frost. Quite a contrast to the warmth in SE England with temperatures still close to 20C after highs up to 30C earlier today. We had our heat yesterday and the day before and tonight we have the return of the autumn chill so it's quite nice to have contrasting but fine autumnal characteristics coupled with some pleasant clear and bright conditions. Lovely!

[Gaz1985]

Am I not mistaken but I thought Scotland could get an air frost any month of the year....are there not just a hand full of days in the year where there has been no air frost recorded??

 

Only 2 months of the year I have never known a crisp air frost here and that's July and August, seen it in every other month.

[Scorcher]

Only 2 months of the year I have never known a crisp air frost here and that's July and August, seen it in every other month.

 

I'm in Denton and have never witnessed an air frost in June or September here. I can't imagine Droylsden is that different. Unless you can give some examples of when it has occurred?

 

I certainly can't find any records of air frost in those months and it's not that common in May or October either.

 

Manchester Airport (a slightly frost-prone location) never once recorded an air frost in June or September between 1960 and 2005.

Edited September 5, 2013 by Scorcher

[Gaz1985]

I'm in Denton and have never witnessed an air frost in June or September here. I can't imagine Droylsden is that different. Unless you can give some examples of when it has occurred?

 

I certainly can't find any records of air frost in those months and it's not that common in May or October either.

 

Whilst an airport reading is an "official" reading for any given city it doesn't necessarily denote what the conditions are actually like miles away from the airport in a random spot like here. Lots of things can contribute even in clear skies a slight breeze can raise temperatures up a degree or two.

 

Last Winter there was times when the airport (10 miles away) had no snow yet here we had a good covering, this area is a microclimate. Just a 20 or 30 metre difference in elevation and being slightly further north and east (most of the time closer to colder air masses) can change things.

 

Anyway for September both in year 2005 note this was for the Airport which is usually a degree warmer than here at most times my own reliable Davis PWS reported -0.8 Â°C on the 17th and -0.3°C on the 24th both are an air frost: 

 

 

17th September 2005 airport went down to 1 degrees http://classic.wunderground.com/history/airport/EGCC/2005/9/17/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

 

24th September went down to 2 degrees at the airport but here in Droylsden we still managed an air frost http://classic.wunderground.com/history/airport/EGCC/2005/9/24/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

 

Only 1 occasion was in June and strangely again in 2005 the airport got down to 2 degrees but here 10 miles away we went down to -0.2

 

http://classic.wunderground.com/history/airport/EGCC/2005/6/7/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

 

But yes I agree that air frost is not that common in May but it can happen....... but October can certainly be a darkhorse with frost - both 1992 and 1993 were particularly cold for the time of year with some moderate frosts, one morning in October 1993 it got down to minus 4 at Manchester airport http://www.tutiempo.net/en/Climate/Manchester_Airport/10-1993/33340.htm. 

 

While 1993 recorded that minus 4 figure overall 1992 was colder than 1993 with 7 air frosts recorded that month! http://www.tutiempo.net/en/Climate/Manchester_Airport/10-1992/33340.htm

 

October 2003 was also chilly with a number of air frosts recorded at the airport. So it can happen and even back to back years, we're due it to happen again soon I would imagine only a matter of time.

Edited September 6, 2013 by Gaz1985

[Eugene]

Whilst an airport reading is an "official" reading for any given city it doesn't necessarily denote what the conditions are actually like miles away from the airport in a random spot like here. Lots of things can contribute even in clear skies a slight breeze can raise temperatures up a degree or two

 

I wouldn't bother reasoning with them gaz, if no official station is recording it in an urban area they will ignore anything in the middle of the countryside in river valleys, river valleys in central Warwickshire get very cold even on calm clear mid summer nights, have recorded temps just below 0C there  in the summer months even in July but nobody would believe me and say i'm lying.

 

 

 

 

 

Edited September 6, 2013 by Eugene

[NorthernRab]

-1'C in altnaharra, first of the season!

[Radiating Dendrite]

Hooray....... and so it begins!

[Relativistic]

Amazing, it's 16.5C here. Great to hear about the first air frost!

[Scorcher]

Whilst an airport reading is an "official" reading for any given city it doesn't necessarily denote what the conditions are actually like miles away from the airport in a random spot like here. Lots of things can contribute even in clear skies a slight breeze can raise temperatures up a degree or two.

 

Last Winter there was times when the airport (10 miles away) had no snow yet here we had a good covering, this area is a microclimate. Just a 20 or 30 metre difference in elevation and being slightly further north and east (most of the time closer to colder air masses) can change things.

 

Anyway for September both in year 2005 note this was for the Airport which is usually a degree warmer than here at most times my own reliable Davis PWS reported -0.8 Â°C on the 17th and -0.3°C on the 24th both are an air frost: 

 

 

17th September 2005 airport went down to 1 degrees http://classic.wunderground.com/history/airport/EGCC/2005/9/17/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

 

24th September went down to 2 degrees at the airport but here in Droylsden we still managed an air frost http://classic.wunderground.com/history/airport/EGCC/2005/9/24/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

 

Only 1 occasion was in June and strangely again in 2005 the airport got down to 2 degrees but here 10 miles away we went down to -0.2

 

 

Gaz I don't doubt that ground frosts are fairly common in this area in September but air frosts are not, September 2005 was certainly exceptional on those couple of nights but there are no readings from official stations that confirm an air frost in this area. In any case it's the only September when I can recall the temperature getting close to 0C around here. That June reading I'd be wary of given the fact it's a whole 2C+ colder than the airport. You'd expect being slightly higher up that the nights would be slightly milder. Certainly the readings I have recorded here have virtually always been warmer than the airport at night.

[Coast]

I know Summer is over when we start this thread!! :lol: 

[Interitus]

-1'C in altnaharra, first of the season!

 

Beat me to it, Altnaharra minimum -2°C overnight with nearby Kinbrace -1.8°C @ 6am and elsewhere in the western Highlands Tulloch Bridge minimum -0.6°C and Tyndrum -0.1° @ 6am.

[marky810]

I seem to recall Thursday 30th Aug 2012 dawning white over here.

[Gaz1985]

Gaz I don't doubt that ground frosts are fairly common in this area in September but air frosts are not, September 2005 was certainly exceptional on those couple of nights but there are no readings from official stations that confirm an air frost in this area. In any case it's the only September when I can recall the temperature getting close to 0C around here. That June reading I'd be wary of given the fact it's a whole 2C+ colder than the airport. You'd expect being slightly higher up that the nights would be slightly milder. Certainly the readings I have recorded here have virtually always been warmer than the airport at night.

 

Thing is I believe the airport sensor is located in a nearby field - away from the runway and buildings so it will probably record lower than some urban places like Denton. Whilst mine is located 100 feet away from my door in a cold valley frost pocket so I know my readings are 99% accurate - one reason why I chose to locate my sensor there in the first place for the interesting readings it gives, I also have another sensor in my garden that I compare with it and it records about a degree higher most of the time, but again this depends on breeze, cloud cover etc.

 

So I don't discount your readings especially IF your sensor is located in an average urban garden like I would imagine most gardens in Denton are, which might be just one reason you record higher than the airport, but again there could another 5 reasons why. 

[Gaz1985]

 

I wouldn't bother reasoning with them gaz, if no official station is recording it in an urban area they will ignore anything in the middle of the countryside in river valleys, river valleys in central Warwickshire get very cold even on calm clear mid summer nights, have recorded temps just below 0C there  in the summer months even in July but nobody would believe me and say i'm lying.

 

 

 

 

 

 

True Eugene even if you had 10 temperature sensors in the same place there's always some people who won't believe you and say the sensors are "not accurate"

[damianslaw]

The lowest official temperature last night was -2.4 in Kinbrace. N Ireland got close to an air frost, Castlederg recorded 0.4 degrees.

 

Much attention yesterday was on the heat of the SE, the cold in the Highlands was hardly mentioned.

 

We will need to rename this thread the first air frost for England and Wales. I was nearly 2 weeks out with my guess for Scotland.

 

Certainly by late Sept it doesn't take much for sheltered northern spots to record an air frost under clear skies, as I said we saw a widespread one on the 22nd Sept last year.