First Air Frost watch season 2016-2017

[iapennell]

24 minutes ago, Ravelin said:

Luck of the draw even with a bit of topographical help. I'm onto my 3rd frost of the month as it hit -0.8C overnight here and I don't think that one was forecast either (so out of 3 only one was forecast).

I don't know what it is about where I live at just over 400 metres above sea-level but the tendency here (despite elevation above sea-level suggesting we ought to get colder nights than the lowlands) is for cloud cover to move in on Autumn nights forecast to be cold. Accu-weather predicts a minimum of 0C for my locality but I am happy to put £££'s on the temperature not falling below 4C again as the cloud-cover remains resolutely persistent over us- not a star to be seen and my AWS remains firmly stuck on 6C!! I would so much love it to surprise on the cold -side at night at this time of year but I cannot remember exactly when that last really happened. 

I remain resolutely of the opinion that most folk on this Forum will not be seeing their first air-frost until the end of this month (myself included). These easterlies, which I do not believe will persist beyond next week, have not come from as far as Siberia and seem to have come across central Europe from no further than Ukraine (thus are not cold) and they seem to have a lot of cloud embedded in them. I do not hold out any hope of the first widespread air-frosts of the season coming courtesy of them for those reasons. 

[Nick L]

I suspect a fair few will have to scrape their cars this morning! Not sure if I'm one of them yet, 2c at a local station though so certainly cold enough to reach for the scraper. Not quite an air frost mind...

[Frosty hollows]

Thick white frost on my car here in the Thames Valley. 1.2C according to my weather station. Brrrr

[Frosty hollows]

8 hours ago, iapennell said:

I don't know what it is about where I live at just over 400 metres above sea-level but the tendency here (despite elevation above sea-level suggesting we ought to get colder nights than the lowlands) is for cloud cover to move in on Autumn nights forecast to be cold. Accu-weather predicts a minimum of 0C for my locality but I am happy to put £££'s on the temperature not falling below 4C again as the cloud-cover remains resolutely persistent over us- not a star to be seen and my AWS remains firmly stuck on 6C!! I would so much love it to surprise on the cold -side at night at this time of year but I cannot remember exactly when that last really happened. 

I remain resolutely of the opinion that most folk on this Forum will not be seeing their first air-frost until the end of this month (myself included). These easterlies, which I do not believe will persist beyond next week, have not come from as far as Siberia and seem to have come across central Europe from no further than Ukraine (thus are not cold) and they seem to have a lot of cloud embedded in them. I do not hold out any hope of the first widespread air-frosts of the season coming courtesy of them for those reasons. 

We had our second air frost of the month last night!

[Ravelin]

9 hours ago, iapennell said:

Accu-weather predicts a minimum of 0C for my locality but I am happy to put £££'s on the temperature not falling below 4C again as the cloud-cover remains resolutely persistent over us- not a star to be seen and my AWS remains firmly stuck on 6C!!

I'm a believer that 'local knowledge' is needed to interpret the 'computer generated' forecasts. For instance, I'm pretty sure that the forecasts for my village are really the forecasts for Dyce. There may only be 12 miles or so between them but that can make a couple of degrees difference at least between what the forecast shows for Kemnay and what we get in reality, primarily because it's 12 miles further inland from the coast.  In the summer I can drive home from work in Dyce and it's a good 2 or 3 degrees warmer at home. In the winter the opposite is true, it's nearly always colder in Kemnay than in Dyce and it's not unusual for me to be clearing snow from the car in the morning only to get to work and there's no sign of any at all.

Nothing wrong as such with the forecasts, it's just that they are too 'course'.

[NorthYorksWeather]

5 minutes ago, Ravelin said:

I'm a believer that 'local knowledge' is needed to interpret the 'computer generated' forecasts. For instance, I'm pretty sure that the forecasts for my village are really the forecasts for Dyce. There may only be 12 miles or so between them but that can make a couple of degrees difference at least between what the forecast shows for Kemnay and what we get in reality, primarily because it's 12 miles further inland from the coast.  In the summer I can drive home from work in Dyce and it's a good 2 or 3 degrees warmer at home. In the winter the opposite is true, it's nearly always colder in Kemnay than in Dyce and it's not unusual for me to be clearing snow from the car in the morning only to get to work and there's no sign of any at all.

Nothing wrong as such with the forecasts, it's just that they are too 'course'.

The computer forecasts are useless, I usually knock a good 2/3 C off what the Met Office are predicting for my village when it comes to nighttime temps. Last night was a great example with 6c being forecast and we fell to 3.8c. 12 miles from Kemnay to Dyce is a long way in weather terms, I live in a village called Low Hutton (30-50m) which is 1 mile from High Hutton (70-80m) and in the 5 years I've lived here even I've noticed some temp/weather differences between the 2 villages. Only us weather freaks would notice this though 

[iapennell]

1 hour ago, vizzy2004 said:

The computer forecasts are useless, I usually knock a good 2/3 C off what the Met Office are predicting for my village when it comes to nighttime temps. Last night was a great example with 6c being forecast and we fell to 3.8c. 12 miles from Kemnay to Dyce is a long way in weather terms, I live in a village called Low Hutton (30-50m) which is 1 mile from High Hutton (70-80m) and in the 5 years I've lived here even I've noticed some temp/weather differences between the 2 villages. Only us weather freaks would notice this though 

The forecast models are also quite poor at discerning the occurrence of orographic cloud-cover, which in a relatively moist flow results in nocturnal cloud-cover over high ground even when the barometer is above 1030 mb, as it has been. 

Well, quele' Surprise!! I awoke at 7.AM to uniform grey cloud-cover and not a trace of frost! I would have predicted that last night because once that thick deck of stratus or stratocumulus is in place and winds are light when you go to bed you can bet your bottom dollar that the cloud is there to stay the remainder of the night and act as a very effective blanket preventing surface radiation loss!

[Nick L]

10 hours ago, iapennell said:

The forecast models are also quite poor at discerning the occurrence of orographic cloud-cover, which in a relatively moist flow results in nocturnal cloud-cover over high ground even when the barometer is above 1030 mb, as it has been. 

Well, quele' Surprise!! I awoke at 7.AM to uniform grey cloud-cover and not a trace of frost! I would have predicted that last night because once that thick deck of stratus or stratocumulus is in place and winds are light when you go to bed you can bet your bottom dollar that the cloud is there to stay the remainder of the night and act as a very effective blanket preventing surface radiation loss!

Much of my job concerns forecasting road temperatures for councils for gritting purposes, and very slight differences in cloud cover have huge impacts on the road temperatures. Completely agree with this, the last few nights especially the models have been poor for this, although with low cloud in general they're poor. 

 

[Walsall Wood Snow]

Even though I didn't witness it because I wasn't up early enough this morning I asked my Mum if there was any frost this morning when she went to work and she said there was some on her car roof. Though she said she didn't have to scrape the Windows and she said she didn't believe there was any on the grass or anything. This sounds like it was something of a very marginal ground frost to me, but either way to my knowledge this marks the first frost of any description here this Autumn.

Edited October 10, 2016 by Walsall Wood Snow

[Evening thunder]

We had 2.2C at 3:05am last night which was the lowest so far, though it rose a bit towards dawn due to some cloud cover.

It's already 3.2C here at the moment so we may get at least a decent ground frost if cloud doesn't come in. Probably not quite an air frost from my experience here, but It's possible.

Edited October 10, 2016 by Evening thunder

[Stargazer]

-0.2C in Farnborough this morning, probably the first air frost in the south this season. Here in our garden in Reading town centre the minimum was 3.4, with the nearest official station at Reading University recording 1.7. Air frosts are quite rare in October here, but we usually get at least one by mid November.

Edited October 12, 2016 by Stargazer

[Evening thunder]

Too much mixing and/or cloud prevented a decent ground frost (or air frost) here this morning, though there was a bit of ice/frost on the car and a felt roof across the road first thing. Min was 1.6C at 1am. 

I notice Yeovilton in Somerset had a min of 0.1C yesterday, and 0.0C today. So close... (I believe -0.1C is required)

Edited October 11, 2016 by Evening thunder

[iapennell]

On 10/10/2016 at 11:37, iapennell said:

The forecast models are also quite poor at discerning the occurrence of orographic cloud-cover, which in a relatively moist flow results in nocturnal cloud-cover over high ground even when the barometer is above 1030 mb, as it has been. 

Well, quele' Surprise!! I awoke at 7.AM to uniform grey cloud-cover and not a trace of frost! I would have predicted that last night because once that thick deck of stratus or stratocumulus is in place and winds are light when you go to bed you can bet your bottom dollar that the cloud is there to stay the remainder of the night and act as a very effective blanket preventing surface radiation loss!

Actually got down to 1.8C on Monday morning, skies must have cleared considerably after midnight but at sunrise there looked to be considerable patchy cloud around and not any evidence of frost. Certainly, the forecast models seem to underestimate the occurrence of nocturnal cloud-cover over hills which can occur readily with relative humidities at sunset of 80% at this time of year: Even with atmospheric subsidence, what airstream reaching the North Pennines is not likely to have relative humidities at dusk of 80% at this time of year unless (possibly) the airstream has a long land-track before reaching the local area (not something that ever applies for east or NE winds). The land is usually moist after substantial rainfall in October and that certainly does not help!!

I stick by my assertion that most of us (including myself at over 400 metres above sea-level in far NE Cumbria) will not be recording our first air-frost until the end of the month or even well into November: Despite the east winds we've had this is holding up.  

[hillbilly]

Most people have to wait until November for a first air frost in most years,not hard to predict that !

 

[damianslaw]

Still waiting for our first air frost of the season. Last night produced a very decent ground frost with surfaces sparkling white and it took quite a while for things to warm up, an indication of how late the sun is rising now, and its rapidly weakening strength - it is as strong now as it is in mid February.

Next few nights will see no frost, but I'm preety confident we willhave recorded our first air frost by the end of next week - a little later than normal.

[ThundersnowDays]

Still waiting for my first ground and air frost here.

On this day last year I saw a small patch of frost but the first proper frost was on the 22nd November so I'm not expecting much yet.

[Walsall Wood Snow]

I've also still yet to see a decent ground frost (though my Mum told me there was a bit on the roof of her car on the 10th of October) and certainly haven't had a air frost, so far this Autumn. This morning though was quite foggy/misty and that was the first of that phenomenon I've seen so far this Autumn which was nice to see. Hopefully I won't have to wait too much longer for my first frost of the Autumn, not that it's particularly late for our first round here of course, I think November bringing the first is more usual.

[NorthYorksWeather]

Narrowly missed out yesterday on our first air frost after a min of 0.2c, likely to be early November before we see one now.

[iapennell]

17 hours ago, damianslaw said:

Still waiting for our first air frost of the season. Last night produced a very decent ground frost with surfaces sparkling white and it took quite a while for things to warm up, an indication of how late the sun is rising now, and its rapidly weakening strength - it is as strong now as it is in mid February.

Next few nights will see no frost, but I'm preety confident we willhave recorded our first air frost by the end of next week - a little later than normal.

Finally got down to 0C with me at 410 metres above sea-level early yesterday morning. Technically this is not an air-frost but my manageress from work had trouble de-icing her car and everything was white! Still had to wait until 25th October to get this cold so my prediction was not far out. And most folk on this Forum still have not recorded air frost as yet

[Walsall Wood Snow]

Actually saw my first ground frost this morning (though as I stated earlier my Mum told me there was some on the roof of her car on 10th October). I didn't get up until 8:30 am and most of it had thawed in the Sun by then but there was still a fair bit about in the shade. It's got quite a bit chillier since yesterday as well so hopefully there will be more to come with hopefully my first air frost of the season not to far away.

[Frost HoIIow]

Got down to bang on -3C here this morning so the first air frost of the season, a decent one at that.

[Daniel*]

I'm dubious we will see. 

[NorthYorksWeather]

Another narrow miss last night after a low of 0.1c, 4 ground frosts so far this Autumn and its already 1.8c at frosty out there now. 

Can we make it below freezing tonight? Cloud looks to increase later in the night so I'm not sure

[cheese]

Fell to 0.9C this morning with a widespread ground frost so close but no cigar.

Edited November 2, 2016 by cheese

[ThundersnowDays]

3rd November, first frost here, patches on the grass.

Later than last year as there was one in October (only a small patch) but then I had to wait until late November for a second one.