Frost - SUB ZERO 2013/14 discussion

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Yorkshire Kris
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Yorkshire Kris »

otorongo wrote:
Yorkshire Kris wrote:Lower than minus one? Well there's minus two, minus three etc... :lol:
Oh, now I get it :lol:

I haven't had a minus one either, but I've had a negative one - namely a -0.8 icon_thumleft

Ditto! Low of -0.8 negative/ zero point eight/minus zero point eight for a few short hours. icon_thumleft
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Dave Brown »

3 frosts now
-0.1C 19/11
-1.5C 20/11
-0.3C 10/12 quite a thick frost though.
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Kristen

Re: Frost - SUB ZERO 2013/14 discussion

Post by Kristen »

I'm still on 1 ... long may that continue as plants are camping in greenhouse waiting for conservatory build to finish ...

-1.5C 19/20 Nov
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Re: Frost - SUB ZERO 2013/14 discussion

Post by otorongo »

I'm still on 1, -0.8C on 19/20 Nov.

Only casualties - Brug leaves.
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Dave Brown »

4 frosts now
-0.1C 19/11
-1.5C 20/11
-0.3C 10/12
-0.6C 11/12 and really struggling to rise with fog, must be an inversion layer
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Steph
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Steph »

My treeferns are all still outside, fronds aren't frosted and they are still pushing out new croziers, Cyatheas included.
T-rexs still have their leaves as well, so far so good I am not complaining.
Kristen

Re: Frost - SUB ZERO 2013/14 discussion

Post by Kristen »

Dave Brown wrote:4 frosts now
-0.1C 19/11
-1.5C 20/11
-0.3C 10/12
-0.6C 11/12 and really struggling to rise with fog, must be an inversion layer
Are they four? or two nights 19/20 Nov and 10/11 Dec (i.e. low temperature before midnight making the day before look like there was a frost)

My weather station logs from 9am - 9am, which avoids the issue; perhaps yours does too?
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Dave Brown »

Kristen wrote:
Dave Brown wrote:4 frosts now
-0.1C 19/11
-1.5C 20/11
-0.3C 10/12
-0.6C 11/12 and really struggling to rise with fog, must be an inversion layer
Are they four? or two nights 19/20 Nov and 10/11 Dec (i.e. low temperature before midnight making the day before look like there was a frost)

My weather station logs from 9am - 9am, which avoids the issue; perhaps yours does too?
Wunderground runs by date, so from 00:00:00 to 23:59:59 so I've had 3 spells of frost... 19/20 Nov were one, but frost on am 10/12 and 11/12.
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Kristen »

Dave Brown wrote:Wunderground runs by date
Good point. Bit annoying though ... I wish they would make other improvements, not seen any useful changes for eons.

Indicating weather stations that are badly calibrated (temperature sores on Summers mornings), ones sitting at silly temperatures because they are bust, or still indoors in their Christmas wrapping paper!! Probably a host of other changes that they could make if they wanted to ...
madgav

Re: Frost - SUB ZERO 2013/14 discussion

Post by madgav »

Kristen wrote:
Dave Brown wrote:Wunderground runs by date
Good point. Bit annoying though ... I wish they would make other improvements, not seen any useful changes for eons.

Indicating weather stations that are badly calibrated (temperature sores on Summers mornings), ones sitting at silly temperatures because they are bust, or still indoors in their Christmas wrapping paper!! Probably a host of other changes that they could make if they wanted to ...
I quite like wunderground for checking what the weather is doing elsewhere (but not for their forecasts).
I dropped them an email earlier this year with a couple of suggestions, one of which was the misleading naming of my two local stations ("Belfast" is actually Belfast International Airport and is 25 miles west of the city in a *much* colder area, so I suggested it would be better named "Aldergrove" or at least "Belfast International" - similar naming issue with "Belfast Harbour" which is now Belfast City Airport). I received a reply with some gobbledygook about using the official names (even though "Aldergrove" *is* the official name of the station :roll: ). Needless to say, nothing changed :wink:

So I wouldn't get your hopes up :roll:

And yes some of the personal/unofficial stations are not very reliable......
madgav

Re: Frost - SUB ZERO 2013/14 discussion

Post by madgav »

Dave Brown wrote: Wunderground runs by date, so from 00:00:00 to 23:59:59 so I've had 3 spells of frost... 19/20 Nov were one, but frost on am 10/12 and 11/12.
Isn't that the more usual method used even for official weather records in most parts of the world? I thought it was just the UKMO who define the low temps as being between 6pm and 9am or something?

My personal records are based on the 00:00:00 to 23:59:59 method. It was easier to program too :wink: Only drawback is it needs 2 mild nights in a row to record a mild low :)
Kristen

Re: Frost - SUB ZERO 2013/14 discussion

Post by Kristen »

madgav wrote:Only drawback is it needs 2 mild nights in a row to record a mild low :)
The other, "only" :lol: , drawback being that one cold night, i.e. also cold before Midnight, records as two cold nights ...

Much better to use 9am - 9am IMHO. I've only had a couple of days, that I can remember!, in the last 3 years or so where the temperature at 9am was colder than the following night's min.

Or am I kidding myself on that last point?
madgav

Re: Frost - SUB ZERO 2013/14 discussion

Post by madgav »

Kristen wrote:
madgav wrote:Only drawback is it needs 2 mild nights in a row to record a mild low :)
The other, "only" :lol: , drawback being that one cold night, i.e. also cold before Midnight, records as two cold nights ...

Much better to use 9am - 9am IMHO. I've only had a couple of days, that I can remember!, in the last 3 years or so where the temperature at 9am was colder than the following night's min.

Or am I kidding myself on that last point?
Haha I don't know :)
But I recall many times seeing the warmest temp at night and the lowest during the day - it only takes a front passing through to completely overwhelm the effects of solar input, especially in winter.
When researching this it seemed that the midnight-to-midnight method is most widely used, but that the Met Office use the other method. The overall advice seemed to be - don't get too hung up on it, just record the weather.... :wink:
Kristen

Re: Frost - SUB ZERO 2013/14 discussion

Post by Kristen »

Perhaps the Night Min/Max should be Dusk-to-Dawn and the Day Min/Max Dawn-to-Dusk :)
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Re: Frost - SUB ZERO 2013/14 discussion

Post by Dave Brown »

In winter warm = cloud cover or warm front, and cold = clear sky or cold front. Max an Min temps can be at any point in the 24 hours. In Summer the daytime is almost always warmer than night as there is so much solar energy it still warms through thick cloud :wink:
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Dave
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