New -- Boards WINTER forecast contest

M.T. Cranium

Winter of 2010-11 forecast contest
________________________________

Here's your chance to make a forecast for the whole winter of 2010-11 in Ireland and earn the admiration of your peers, plus any valuable gifts that materialize from the ambient surroundings.

This may seem like a bridge too far to some of our regular monthly forecast entrants, but you're all in the same boat and playing by the same rules, so give it a try -- and please note the rules very carefully because some of them are different from the monthly rules. I considered having a secret ballot where your forecast only appeared after the deadline, but decided that would probably result in a reduced field of entrants and more work for the organizers.

Thanks to Hellboy99, I have an assistant who will be able to tabulate the entries once all received. Without further ado then, here are the rules and please note very carefully,

the deadline for entries will be Wednesday 17 November at 2359h GMT

and this will be an inflexible rule, no exceptions.

Just for reference, you should read the contest questions, then fill in the contest entry form at the end, block copy it, and post your filled-out form, or you have the option to PM it to myself or to Hellboy99, for which we will issue a receipt and place a notice in the thread (such as "Kevinfromcarrymecarefully has placed an entry.")

CONTEST QUESTIONS (and weighted points)
__________________________________

(1) Predict the IMT value for each of the primary winter months, December, January and February. For your reference, IMT is a simplified national average explained in the monthly threads using five central Ireland stations, and the 1961-90 values of these are

Dec 5.3
Jan 4.6
Feb 4.7

If you are unfamiliar with this concept, please note, a monthly mean temperature is the average of daily highs and overnight lows (or whenever these occur) through the month. A mean of 5.3, for instance, could refer to average daytime readings near 8.3 and average night minima near 2.3.

These monthly values are each worth 10% of the total points. The seasonal average, worked out by us from your entries, is worth 20% of the total points, for a total of 50%.

(2) Predict the total precipitation for the three months, first for each month, then we take a seasonal average from your predictions ... and these should be in percentage of normal. For example, you could say 75% Dec, 110% Jan, 100% February ... and this would reduce to 95% for the season. Note -- we will be taking the raw average of months and not the slightly different seasonal value (these can vary by 1-2 per cent because February is a shorter month, but it won't affect the scoring enough to worry about it).

These monthly values are each worth 5% of the total points, and so is the seasonal average, for a total of 20%

(3) Predict the highest and lowest temperatures in the period 1 Dec 2010 to 28 Feb 2011 at the regularly listed weather stations on the met.ie website. If unfamiliar with that list, please check them out and note the absence of very cold second-order rural stations that might show up in climate bulletins later. Last winter we saw some readings at these out-of-contest stations that were five degrees or so lower than the "official" stations.

These two predictions will each be worth 5% of the points for a combined 10%.

(4) Predict the strongest wind gust in knots on land at the same met.ie stations as mentioned in the previous question. One knot is approximately 1.8 km/hr if that's helpful to you, or about 14% greater than m.p.h. Values between 50 and 100 have verified in recent winters. This is an estimate, but 80 knots would be about the average value for this question.

This prediction is worth ten per cent of the total.

(5) Predict the total snowfall for the "contest winter season" at Casement. The "contest winter season" will be defined as 1 November to 31 March. Any snow that happens to fall in October, April or May (or later) will not count towards this contest question. Any snow that has already fallen in November before your entry will count. Give your answer in centimetres.

This prediction is worth ten per cent of the total.

---

Scoring rules

Monthly (and seasonal in brackets) mean temperatures will be scored as follows:

10 (20) points for correct or within 0.1

9 (18) points for 0.2 or 0.3 errors

8 (16) points for 0.4 or 0.5 errors

etc

to 1 (2) points for 1.8 or 1.9 errors

or, if applicable, a minimum scoring rule will apply, ensuring that by rank order, one third of entrants score and by rank order of predictions, with ties equally distributed and towards the bottom end of the scores where necessary. For example, if a month is considerably different from most predictions, the scoring will go to the one-third of entrants closest to that value and all points but 10 (20) must be awarded.

For the seasonal max and min, these will be scored by taking half of whichever of the following gives the fairer allocation of points, with half points preserved in the scoring:

(one half of ...)

(a) 10 points for a direct hit or 0.1 error, down to 1 point for 1.8 or 1.9 error,

or (b) points from rank order given to top ten entries, extending to as many as necessary with ties for 2 and 1 points (the 2s not excluding the 1s but above that, ties would exclude, for example, three tied at 5 would give 2 as the next score).

(b) would only be used if (a) fails to generate 8, 5, 3, 2, 1 as a minimum for the field at large.

For the rainfall averages, the same logic as above would apply, including the half points, with the error ranges changed from 0.1 degree to 3 per cent. For example, 97-103 per cent qualifies as full points if verification is 100%.

For the wind forecast, the ten points are awarded in rank order, with ten entrants receiving points for 10-19 entries, 20 for 20-29 (in pairs) or 30 for any greater number (in triples, for example, three closest get 10 points in that scenario).

For the snowfall forecast, the ten points are also awarded in rank order, with ten points for the closest, nine for second closest, etc, and these will also be doubled or tripled up if the field is large enough.

Note that there are no sunshine forecasts required, it was felt that this variable would be too closely correlated with other variables to provide any real measure of accuracy.

---

Now, once you've thought about your forecast and come to an understanding on the rules, please use this form to submit an entry:

1. DEC IMT will be
JAN IMT will be
FEB IMT will be
(average -- you can submit, but we will check your math, or we do it for you)

2. DEC precip will be ___ %
JAN precip will be ___ %
FEB precip will be ___ %
(average -- see above)

3. Max temp for the three months _____
Min temp for the three months _____

4. Highest wind gust in knots ____ kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar _________

OPTIONAL comments ________________________


Thanks for entering. We will contact anyone whose entries seem to be outside the range of possible values to confirm the parameters. But you are ultimately responsible for understanding the contest rules and the measurements by which validation occurs. Please note all temperatures will be converted to tenths (and scored likewise) if submitted in round numbers.

Please address questions on the thread as others may have similar questions, or PM if you prefer. Please note the private entry option explained above.

The rules may be amended if discussion on the thread gives any reason for clarification or amendment. The rules as posted on 18 November will be final. Early entrants have the option to amend their forecasts by the deadline.

WolfeIRE

thanks MT and Hellboy!

1. DEC IMT will be 5.9
JAN IMT will be 4
FEB IMT will be 5.3

2. DEC precip will be 85%
JAN precip will be 105 %
FEB precip will be 120 %

3. Max temp for the three months 14.5c
Min temp for the three months - 11.5c

4. Highest wind gust in knots 61 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar ----16

OPTIONAL comments __What is the average wing speed velocity of an unladen swallow?

Su Campu

Just one question MT - where will you get the actual snow cms figure from? As far as I know met.ie doesn't report snow depths. It would be a bit controversial using a liquid-frozen conversion, as this can vary widely depending on snow type

M.T. Cranium

Ogimet? If not, we will work this out by consensus. Perhaps somebody on the forum can go in and get the answers at source. I will put the word out, who lives within 10-15 miles of Casement? That might be a good start.

Maybe I will come over and pitch my tent. :cool:

Danno

1. DEC IMT will be 5.7
JAN IMT will be 2.9
FEB IMT will be 3.7

2. DEC precip will be 75%
JAN precip will be 110 %
FEB precip will be 110 %

3. Max temp for the three months 15.7c
Min temp for the three months -9.7c

4. Highest wind gust in knots: 77kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 27cm

I can supply the snow depth data if need be... but I am 60 miles SW of Casement, so a change of station for this question would be required.

Su Campu

M.T. Cranium wrote: »

Ogimet? If not, we will work this out by consensus. Perhaps somebody on the forum can go in and get the answers at source. I will put the word out, who lives within 10-15 miles of Casement? That might be a good start.

Maybe I will come over and pitch my tent. :cool:

I'm still not clear what the snow cms means and how it can be calculated. I can't see anywhere on Ogimet that reports snowfall depths, only lying snow depths, so one snowfall can be reported for days if it doesn't melt. In this contest, what does the total cms mean? At the end of the winter, how can we tot up the total snowfall?

Lumi

M.T. Cranium wrote: »

Ogimet? If not, we will work this out by consensus. Perhaps somebody on the forum can go in and get the answers at source. I will put the word out, who lives within 10-15 miles of Casement? That might be a good start.

Maybe I will come over and pitch my tent. :cool:

I just checked Ogimet's data for last January and they do indeed have the snow depths for Casement so that should work fine

http://www.ogimet.com/cgi-bin/gsynres?lang=en&ind=03967&ndays=30&ano=2010&mes=02&day=01&hora=00&ord=REV&Send=Send

Su Campu

Fionagus wrote: »

I just checked Ogimet's data for last January and they do indeed have the snow depths for Casement so that should work fine

http://www.ogimet.com/cgi-bin/gsynres?lang=en&ind=03967&ndays=30&ano=2010&mes=02&day=01&hora=00&ord=REV&Send=Send

Yes, but they're only the average depth of lying snow that day. They give no indication of the depth of new snow that fell that day (if any).

Eg. take the 11th January summary (it says 8cms in your link above).

At the start of that day, the lying snow was 10cms, but 5cms melted during the day, leaving 5cms remaining that night. The average was therefore 7.5 (rounded to 8)cms. What use is that figure in this contest? No snow fell that day.

http://www.ogimet.com/display_synops.php?lang=en&lugar=03967&ord=REV&nil=SI&fmt=html&tipo=ALL&anof=2010&mesf=01&dayf=11&horaf=00

The lying snow is reported in the "4xxxx" group after the 333// group, on the second line). The report below shows 5cms lying at 00UTC on the 11th.

[SIZE=-1]AAXX 11001[/SIZE] [SIZE=-1]03967 11465 70906 10021 20009 30080 40197 57014 60011 76062 875//
333 42005 81712 87650=

[/SIZE]

Lumi

Su Campu wrote: »

Yes, but they're only the average depth of lying snow that day. They give no indication of the depth of new snow that fell that day (if any).

Eg. take the 11th January summary (it says 8cms in your link above).

At the start of that day, the lying snow was 10cms, but 5cms melted during the day, leaving 5cms remaining that night. The average was therefore 7.5 (rounded to 8)cms. What use is that figure in this contest? No snow fell that day.

http://www.ogimet.com/display_synops.php?lang=en&lugar=03967&ord=REV&nil=SI&fmt=html&tipo=ALL&anof=2010&mesf=01&dayf=11&horaf=00

The lying snow is reported in the "4xxxx" group after the 333// group, on the second line). The report below shows 5cms lying at 00UTC on the 11th.


[/SIZE]

Your dead right Su, it is just a record of lying snow! - Sorry about that, I didn't read it properly

nacho libre

1. DEC IMT will be 4.5
JAN IMT will be 3.3
FEB IMT will be 4.6

2. DEC precip will be 70%
JAN precip will be 110 %
FEB precip will be 105 %

3. Max temp for the three months 14.6c
Min temp for the three months -9.4c

4. Highest wind gust in knots: 80 Knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 22cm

Deep Easterly

I'm sure met eireann would have the exact measurments of fallen snow at Casement when the winter is done and dusted with. Perhaps it might be worth contacting them?

Or how about scraping the snow measurement question and go for the number of days with lying snow at the station for the winter period just to make things a little easier???

Just a couple of suggestions*..:o

nacho libre

Deep Easterly wrote: »

I'm sure met eireann would have the exact measurments of fallen snow at Casement when the winter is done and dusted with. Perhaps it might be worth contacting them?

Or how about scraping the snow measurement question and go for the number of days with lying snow at the station for the winter period just to make things a little easier???

Just a couple of suggestions*..:o

yes. and how about as a bonus question:
we are asked when the first snowfall will be recorded at any of the met stations?

patneve2

optimistic winter snow accumulation predictions there!!

TheInquisitor

1. DEC IMT will be 5.2
JAN IMT will 3.4
FEB IMT will 4.6
(average 4.4? you can submit, but we will check your math, or we do it for you)

2. DEC precip will be 59 %
JAN precip will be 135 %
FEB precip will be 102 %
(average -- see above)

3. Max temp for the three months 13.7
Min temp for the three months -9.8

4. Highest wind gust in knots 68 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 19cm

OPTIONAL comments . MT the amount of time you put into your opening post astounds me. Thank you very much. We wouldn't have a weather forum without you! By the way that £10 is half yours because i used your forecast to place my bet!!! Spot on!! Thanks again

1. DEC IMT will be 5.3
JAN IMT will be 4
FEB IMT will be 4.3

2. DEC precip will be 77%
JAN precip will be 109 %
FEB precip will be 112 %

3. Max temp for the three months 15c
Min temp for the three months -11c

4. Highest wind gust in knots: 78 Knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 32cm

thetonynator

1. DEC IMT will be 4.8
JAN IMT will be 4.9
FEB IMT will be 4.5

2. DEC precip will be 80%
JAN precip will be 110
FEB precip will be 80%

3. Max temp for the three months 13.7
Min temp for the three months -7.8

4. Highest wind gust in knots 55 knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 17.5cm

OPTIONAL comments _ Great work lads, a lot of effort and time gone into this!!!

Deep Easterly

1. DEC IMT will be 6.7c
JAN IMT will be 6.3c
FEB IMT will be 4.9c

2. DEC precip will be 70%
JAN precip will be 140%
FEB precip will be 330%

3. Max temp for the three months 15.3c
Min temp for the three months -6.3c

4. Highest wind gust in knots 88 Knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 3cm

OPTIONAL comments: It's all fun and games till someone loses an eye.

gothwalk

1. DEC IMT will be 4.9
JAN IMT will be 3.7
FEB IMT will be 3.9

2. DEC precip will be 85 %
JAN precip will be 85 %
FEB precip will be 110 %

3. Max temp for the three months: 15.5
Min temp for the three months: -6.5

4. Highest wind gust in knots: 65 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 21.5cm

gothwalk

Deep Easterly wrote: »

1
FEB precip will be 330%

Right. Cubit measuring stick, and you animals, start pairing off there!

homolumo

1. DEC IMT will be 5.9
JAN IMT will be 4.1
FEB IMT will be 4.2

2. DEC precip will be 81%
JAN precip will be 116 %
FEB precip will be 121 %

3. Max temp for the three months 15.3c
Min temp for the three months -9.0c

4. Highest wind gust in knots: 69 Knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 12 cm

pauldry

1. DEC IMT will be 5.8c
JAN IMT will be 4.2c
FEB IMT will be 5.7c

2. DEC precip will be 108%
JAN precip will be 102%
FEB precip will be 105%

3. Max temp for the three months 15.0c
Min temp for the three months -7.1c

4. Highest wind gust in knots 75 Knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 25cm

OPTIONAL comments: A Winter without snow is like a desert without icecream

thetonynator

thetonynator wrote: »

1. DEC IMT will be 4.8
JAN IMT will be 4.9
FEB IMT will be 4.5

2. DEC precip will be 80%
JAN precip will be 110
FEB precip will be 80%

3. Max temp for the three months 13.7
Min temp for the three months -7.8

4. Highest wind gust in knots 55 knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 17.5cm

OPTIONAL comments _ Great work lads, a lot of effort and time gone into this!!!

I know i'm being awkward here but i've decided to edit my entry if its all right with ye!!!

I thought to myself that theres no point in wishing for one thing to happen and having another thing forecasted, so i cant have a win win situation!!!

So this is a mix of what I am hoping for and what i think will happen (although i have to say it is a lot more of what i'm hoping for and a lot less of what I think will happen!!)


1. DEC IMT will be 3.5
JAN IMT will be 2.0
FEB IMT will be 3.0

2. DEC precip will be 70%
JAN precip will be 65%
FEB precip will be 75%

3. Max temp for the three months 13.0
Min temp for the three months -12.5

4. Highest wind gust in knots 40 knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 40cm

Su Campu

So, what's the story about the snow cms? How are they going to be calculated?

M.T. Cranium

We'll clarify this later this week, but if it becomes preferable to take Danno's helpful suggestion of using his station in Laois, where such measurements can be guaranteed, then all contestants will be notified and given the opportunity to revise their prediction if they feel a different location would change their guess. I'm hoping to get a confirmation from a request that we can get official measurements from Casement, as the ogimet data will not quite be the same thing as what we need.

It's my bad, over this way, snowfall amounts are routinely available in climate stats as the days go by, and here's how they are measured by the way ... at every standard three hour observation the snow depth in that three hour period is measured on a standard (and previously cleared) surface. These amounts, potentially eight in total, are added together. That's the daily snowfall in cms (or inches), even if some of it melts and the daily (once daily let's say) depth might be considerably less as a result. Or it may be more at some sites due to drifting. Usually it's less. I've measured snow many times for my amateur weather stations, but in the climate that I lived in, once a day was usually about the same as these cumulative amounts. However I do remember one time when six inches fell overnight (it was Oct 22-23, 1969) and the snow depth at noon was about half an inch then at 6 p.m. it was all gone. But for the contest, a day like that would count as 6 inches.

Anyway, if you've entered, just think about whether or not a change in location further inland to the southwest, would make you want to revise your forecast amount or not, and then we'll clarify the point we're going to use, so people not entered yet may as well hold off until this happens. I just need to discern whether this measurement is actually taken by anybody or if the once daily figure is all they do. Then I need to find out if we can know about it early enough in the year to service the contest.

M.T. Cranium

bump to the top ... if anyone's wondering what my forecast is, so am I. :cool:

200motels

1. Dec 5.1
Jan 4.9
Feb 4.4 2.Dec -4.9 12.7 Jan -6.8 11.9 Feb -4.1 15.9
3. Dec 121 Jan 130 Feb 120
4. Dec 58 Jan 60 Feb 49
5. 8cm
I hope I've done it right.

M.T. Cranium

No worries 200m, only the extremes for the season rather than each month, so we'll take your entry as -6.8 and 15.9 in that regard. Everything else is fine.

Lumi

1. DEC IMT will be 5.3C
JAN IMT will be 3.9C
FEB IMT will be 4.7C
(average 4.6C )

2. DEC precip will be 78% %
JAN precip will be 100%
FEB precip will be 113 %
(average 97%)

3. Max temp for the three months 15.9C
Min temp for the three months -10.1C

4. Highest wind gust in knots 71kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 21cm

M.T. Cranium

Update on the contest. I contacted Met Eireann about the verification of snow depths at Casement. So far I haven't heard back. I will wait until 10 November and if I haven't resolved that issue, I will let all contestants know that we are switching the location. You may then adjust your prediction if you wish.

Also, on reading over the rules, I noticed that it was not specified that the period for maximum wind gust was intended to be 1 December to 28 February as with the extreme temperatures. Wind gusts observed in November or March will not count in validation.

If that causes you to revise your wind gust forecast, please let us know.

Strasser

1. DEC IMT will be 6.2
JAN IMT will be 5.4
FEB IMT will be 6.1
(average -- you can submit, but we will check your math, or we do it for you)

2. DEC precip will be ___110 %
JAN precip will be ___115 %
FEB precip will be ___105 %
(average -- see above)

3. Max temp for the three months _____ 16.5
Min temp for the three months _____-6.8

4. Highest wind gust in knots ____86 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar _________ 10cm

dasa29

1. DEC IMT will be 5
JAN IMT will be 4
FEB IMT will be 4.5

2. DEC precip will be 105 %
JAN precip will be 95%
FEB precip will be 90 %

3. Max temp for the three months 12
Min temp for the three months -12

4. Highest wind gust in knots 80 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 30cm

Su Campu

M.T. Cranium wrote: »

Update on the contest. I contacted Met Eireann about the verification of snow depths at Casement. So far I haven't heard back. I will wait until 10 November and if I haven't resolved that issue, I will let all contestants know that we are switching the location. You may then adjust your prediction if you wish.

Hi MT, I know it's been a hectic few days, but is there any change of location for the snow forecast?

Thanks

M.T. Cranium

Did you notice I mentioned getting a virus a few days ago (in my computer, not my head)? One of the nasty things it did was to send most of my e-mail to trash without me getting to read it. Thus I may have missed met's reply to my request about Casement, as I missed about half a dozen other expected e-mails last week. The odd thing is, the virus quite likely jumped in from that storm thread (a post had a link that I thought was going to be storm pictures and turned out to be total spam).

Well, I have renewed my request for information on Casement's elusive snowfall (if any) and if we don't get resolution by the 18th, I will go with Danno's generous offer and give all contestants notice and adequate time to review their prediction for his somewhat different exposure (although I would have to think that the climatology numbers are about the same). In my case, I haven't posted an entry yet, but here goes (and my snowfall would remain the same for either).

DEC 2.5
JAN 2.4
FEB 2.6
mean 2.5

PRECIP - Dec 120%
Jan 110%
Feb 60%

mean 97%

Temp extremes 13.5 and -13.8

Extreme wind gust 79 kn

Snowfall 67 cms

Just posted my long-range forecast in the winter thread, that will give a rationale for my madness. I think the winter could be even colder than what's predicted here but this should do for now.

Winger_PL

Here goes:

1. DEC IMT will be 3.7
JAN IMT will be 2.9
FEB IMT will be 3.7

2. DEC precip will be 105%
JAN precip will be 95 %
FEB precip will be 110 %

3. Max temp for the three months 13.0c
Min temp for the three months -18.0c

4. Highest wind gust in knots 74 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar ----38

Su Campu

1. DEC IMT will be 5.2
JAN IMT will be 4.6
FEB IMT will be 4.5
(average 4.8)

2. DEC precip will be 110 %
JAN precip will be 85 %
FEB precip will be 90 %
(average 92.3 see above)

3. Max temp for the three months 13.8
Min temp for the three months -7.1

4. Highest wind gust in knots 65 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 25cms

SeaFields

1. DEC IMT will be 4.8
JAN IMT will be 4.1
FEB IMT will be 6.0
(average 5.0)

2. DEC precip will be 80 %
JAN precip will be 75 %
FEB precip will be 120%
(average -- 92%)

3. Max temp for the three months 16.5
Min temp for the three months -12.1

4. Highest wind gust in knots 60 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 10cm

OPTIONAL comments If I'm wrong, may we all be frozen from above somehow

H2UMrsRobinson

1. DEC IMT will be 6.7
JAN IMT will be 5.9
FEB IMT will be 5.8
(average 6.1-you - you can submit, but we will check your math, or we do it for you)

2. DEC precip will be __95_ %
JAN precip will be _110__ %
FEB precip will be _107__ %
(average -104- see above)

3. Max temp for the three months __14.1___
Min temp for the three months __-11.2___

4. Highest wind gust in knots __92__ kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar ___36cms______

OPTIONAL comments _This is my first attempt so i'm kinda plucking numbers out of my ear but though it'd be worth a go, good luck everyone____________________

Mmcd

1. DEC IMT will be 3.8
JAN IMT will be 3.7
FEB IMT will be 4.7
(average 4.07)

2. DEC precip will be 70 %
JAN precip will be 75 %
FEB precip will be 130%
(average -- 91.67%)

3. Max temp for the three months 14.5
Min temp for the three months -13.0

4. Highest wind gust in knots 75 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 24cm

OPTIONAL comments: I don't mind at all if I'm wrong.......as long as it turns out colder!

kindredspirit

1. DEC IMT will be 6.0°C
JAN IMT will be 4.5°C
FEB IMT will be 4.9°C
(average -- you can submit, but we will check your maths, 5.13°C)

2. DEC precip will be 110 %
JAN precip will be 98 %
FEB precip will be 115 %
(average -- about 8% wetter)

3. Max temp for the three months 15.5°C
Min temp for the three months -7.8°C
4. Highest wind gust in knots 80 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 20 cm.

OPTIONAL comments : Haven't a clue.............honestly.

John mac

DEC IMT will be 5.0
JAN IMT will be 4.7
FEB IMT will be 4.5
(average 4.73 you can submit, but we will check your math, or we do it for you)

2. DEC precip will be 110 %
JAN precip will be 100 %
FEB precip will be 90 %
(average 100 see above)

3. Max temp for the three months 14.2
Min temp for the three months -9.8

4. Highest wind gust in knots 76 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 24

Trogdor

1. DEC IMT will be 3.2C
JAN IMT will be 3.4C
FEB IMT will be 2.9C
(average 3.166,,,C)

2. DEC precip will be 90 %
JAN precip will be 100 %
FEB precip will be 70 %
(average 86.66,,,%)

3. Max temp for the three months: 13.4C
Min temp for the three months: -11.9C

4. Highest wind gust in knots: 88 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 38cm

Redsunset

1. DEC IMT 2.6
JAN IMT 1.7
FEB IMT 2.1

2. DEC precip will be 105 %
JAN precip will be 115%
FEB precip will be 110%

3. Max temp for the three months 11
Min temp for the three months -19

4. Highest wind gust in knots 76kt

5. Snowfall in cms 160


All out blizzards on the way this winter and record cold

DOCARCH

1. DEC IMT will be 3.6C
JAN IMT will be 2.8C
FEB IMT will be 3.4C
(average 3.266C)

2. DEC precip will be 89%
JAN precip will be 92%
FEB precip will be 85%
(average 88.66%)

3. Max temp for the three months: 14.1C
Min temp for the three months: -12.6C

4. Highest wind gust in knots: 88 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar: 42cm

octo

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar:

Follks, its not possible to get an accumulated snowfall over such a long period. Not in Ireland anyway, which often operates on the borderline between night-ice and day-melt for much of the winter.

Think about it. Met Eireann measures snow on the ground, which melts. 5 cm of snow today probably won't be 5cm tomorrow.

Best start coming up with an alternative measure........

John mac

octo wrote: »

Follks, its not possible to get an accumulated snowfall over such a long period. Not in Ireland anyway, which often operates on the borderline between night-ice and day-melt for much of the winter.

Think about it. Met Eireann measures snow on the ground, which melts. 5 cm of snow today probably won't be 5cm tomorrow.

Best start coming up with an alternative measure........

http://www.boards.ie/vbulletin/showpost.php?p=68543992&postcount=3

Joe Public

1.
Dec IMT will be 4.9
Jan IMT will be 2.9
Feb IMT will be 3.5
( average 3.8 )

2.
Dec precip will be 130 %
Jan precip will be 60%
Feb precip will be 60 %
( average 83% )

3.
Max temp for the three months 13.9
Min temp for the three months -13.9

4. Highest wind gust in knots 73 kt

5. Snowfall in cms at Casement, or maybe Durrow, for period 1 Nov to 31 Mar - 16cm (before it melts ) Depends on what time Danno get out of bed at.

M.T. Cranium

Well, it is true that my concept of snowfall is based on North American and not (evidently) European practice. Over here, what we do is to measure snowfall each day, actually at 3-hour intervals, keeping a record of snow depths that accumulate (temporarily in some cases) and then summing those up daily, monthly and seasonally. This is what is meant when somebody (routinely) quotes the annual average snowfall at say Chicago to be 35" or whatever it is. In all likelihood, that 35" implies that perhaps 10-15" might be on the ground at a maximum at any time in the winter, but everyone in weather circles knows that 35" means a total snowfall for the season and includes such variables as freeze-thaw, drifting, different moisture ratios etc.

So I mistakenly thought that European stations measured the same thing and apparently they do things differently, as confirmed by an e-mail I just got, and there is no such thing as a "seasonal snowfall total" but there could be one, of course, if somebody kept track of it. Now Danno told me earlier that he measures snowfall routinely when it happens (which being in southern Laois might not be quite as often as elsewhere?) ... so what I would say here is, look at your prediction, imagine what therefore might be the right answer for Durrow in Laois rather than Casement, and if you want to adjust your figure, then go ahead and do so.

You don't have to resubmit the whole forecast, just post a new snowfall total for the season. If you are prepared to stick with your original forecast, then would you take a moment to "thank" this post and that will tell us (me and Hellboy99) that you are staying with the original.

Now, the forecast contest closes at the end of play on the 18th (Thursday) but I will check the files and see who hasn't either signed off or changed, and send those people a note giving them to end of Sunday to change just the snowfall if they wish.

Sorry about the confusion. Perhaps if your climate shifts to something colder you too will know the thrills and joys of regular snowfall measurement. It's odd that the two different systems evolved, you would think the WMO would have standardized something like this years ago, but evidently not.

In reality, I think the snowfall estimates will probably stand or fall on the basis of about five to ten individual snowfall events that we could have estimated from snow depths reported from Casement, so I will try to keep a running estimate of what that might be just for comparison purposes. For example, in North American practice, let's say it's raining with snow mixing in and nothing sticks on the ground, then the snowfall might be reported as trace or even 0.1 cm or some small amount, but if the snow were to stick for a few hours and then melt, it would get into the records as the full amount that fell even though that might not be on the ground even at the end of that day. As I explained earlier, snowfall in these climates tends to stick around longer so that your daily end-of-day snowdepth reflects to a fairly consistent degree the new snow that has fallen that day, but with some settling. For example, if we had ten inches on the ground at some snowy location, and the day produced six new inches, the snow depth would very likely be something like 13-14 inches due to settling and compaction. So using snow depths especially in a more marginal climate would lead to problems in this measurement.

Su Campu

Here's the official WMO guide to Instruments and Methods of Observation. Snow depths is in Chapter 6, page 148.

6.7 Measurement of snowfall and snow cover

The authoritative texts on this topic are
WMO (1994) and WMO (1992a), which cover the
hydrological aspects, including the procedures,
for snow surveying on snow courses. The following
is a brief account of some simple and
well-known methods, and a brief review of the
instrumentation.

Snowfall is the depth of freshly fallen snow deposited
over a specified period (generally 24 h). Thus,
snowfall does not include the deposition of drifting
or blowing snow. For the purposes of depth
measurements, the term “snow” should also
include ice pellets, glaze, hail, and sheet ice
formed directly or indirectly from precipitation.
Snow depth usually means the total depth of
snow on the ground at the time of observation.
The water equivalent of a snow cover is the vertical
depth of the water that would be obtained by
melting the snow cover.

6.7.1 Snowfall depth
Direct measurements of the depth of fresh snow on
open ground are taken with a graduated ruler or
scale. A sufficient number of vertical measurements
should be made in places where drifting is considered
absent in order to provide a representative
average. Where the extensive drifting of snow has
occurred, a greater number of measurements are
needed to obtain a representative depth. Special
precautions should be taken so as not to measureany previously fallen snow. This can be done by
sweeping a suitable patch clear beforehand or by
covering the top of the old snow surface with a
piece of suitable material (such as wood with a
slightly rough surface, painted white) and measuring
the depth accumulated on it. On a sloping
surface (to be avoided, if possible) measurements
should still be taken with the measuring rod vertical.
If there is a layer of old snow, it would be
incorrect to calculate the depth of the new snow
from the difference between two consecutive measurements
of total depth of snow since lying snow
tends to become compressed and to suffer
ablation.

6.7.2 Direct measurements of snow
cover depth
Depth measurements of snow cover or snow accumulated
on the ground are taken with a snow
ruler or similar graduated rod which is pushed
down through the snow to the ground surface. It
may be difficult to obtain representative depth
measurements using this method in open areas
since the snow cover drifts and is redistributed
under the effects of the wind, and may have
embedded ice layers that limit penetration with a
ruler. Care should be taken to ensure that the
total depth is measured, including the depth of
any ice layers which may be present. A number of
measurements are taken and averaged at each
observing station.
A number of snow stakes, painted with rings of
alternate colours or another suitable scale,
provide a convenient means of measuring the
total depth of snow on the ground, especially in
remote regions. The depth of snow at the stake
or marker may be observed from distant ground
points or from aircraft by means of binoculars or
telescopes. The stakes should be painted white
to minimize the undue melting of the snow
immediately surrounding them. Aerial snow
depth markers are vertical poles (of variable
length, depending on the maximum snow depth)
with horizontal cross-arms mounted at fixed
heights on the poles and oriented according to
the point of observation.
The development of an inexpensive ultrasonic
ranging device to provide reliable snow depth measurements
at automatic stations has provided a
feasible alternative to the standard observation,
both for snow depth and fresh snowfall (Goodison
and others, 1988). This sensor can be utilized to
control the quality of automatic recording gauge
measurements by providing additional details on
the type, amount and timing of precipitation. It is
capable of an uncertainty of ±2.5 cm.

6.7.3 Direct measurements of snow
water equivalent
The standard method of measuring water equivalent
is by gravimetric measurement using a snow
tube to obtain a sample core. This method serves as
the basis for snow surveys, a common procedure in
many countries for obtaining a measure of water
equivalent. The method consists of either melting
each sample and measuring its liquid content or by
weighing the frozen sample. A measured quantity
of warm water or a heat source can be used to melt
the sample.
Cylindrical samples of fresh snow may be taken
with a suitable snow sampler and either weighed or
melted. Details of the available instruments and
sampling techniques are described in WMO (1994).
Often a standard raingauge overflow can be used
for this method.
Snowgauges measure snowfall water equivalent
directly. Essentially, any non-recording precipitation
gauges can also be used to measure the water
equivalent of solid precipitation. Snow collected
in these types of gauges should be either weighed
or melted immediately after each observation, as
described in section 6.3.1.2. The recording-weighing
gauge will catch solid forms of precipitation as
well as liquid forms, and record the water equivalent
in the same manner as liquid forms (see
section 6.5.1).
The water equivalent of solid precipitation can also
be estimated using the depth of fresh snowfall. This
measurement is converted to water equivalent by
using an appropriate specific density. Although the
relationship stating that 1 cm of fresh snow equals
the equivalent of 1 mm of water may be used with
caution for long-term average values, it may be
highly inaccurate for a single measurement, as the
specific density ratio of snow may vary between
0.03 and 0.4.
6.7.4 Snow pillows
Snow pillows of various dimensions and materials
are used to measure the weight of the snow that
accumulates on the pillow. The most common
pillows are flat circular containers (with a diameter
of 3.7 m) made of rubberized material and filled
with an antifreeze mixture of methyl alcohol and
water or a methanol-glycol-water solution. The
pillow is installed on the surface of the ground,flush with the ground, or buried under a thin layer
of soil or sand. In order to prevent damage to the
equipment and to preserve the snow cover in its
natural condition, it is recommended that the site
be fenced in. Under normal conditions, snow
pillows can be used for 10 years or more.
Hydrostatic pressure inside the pillow is a measure
of the weight of the snow on the pillow. Measuring
the hydrostatic pressure by means of a float-operated
liquid-level recorder or a pressure transducer
provides a method of continuous measurement of
the water equivalent of the snow cover. Variations
in the accuracy of the measurements may be
induced by temperature changes. In shallow snow
cover, diurnal temperature changes may cause
expansion or contraction of the fluid in the pillow,
thus giving spurious indications of snowfall or
snow melt. In deep mountain areas, diurnal temperature
fluctuations are unimportant, except at the
beginning and end of the snow season. The access
tube to the measurement unit should be installed
in a temperature-controlled shelter or in the ground
to reduce the temperature effects.
In situ and/or telemetry data-acquisition systems
can be installed to provide continuous measurements
of snow water equivalent through the use of
charts or digital recorders.
Snow pillow measurements differ from those taken
with standard snow tubes, especially during the
snow-melt period. They are most reliable when the
snow cover does not contain ice layers, which can
cause “bridging” above the pillows.
A comparison of the water equivalent of snow
determined by a snow pillow with measurements
taken by the standard method of weighing shows
that these may differ by 5 to 10 per cent.

6.7.5 Radioisotope snowgauges
Nuclear gauges measure the total water equivalent
of the snow cover and/or provide a density profile.
They are a non-destructive method of sampling and
are adaptable to in situ recording and/or telemetry
systems. Nearly all systems operate on the
principle that water, snow or ice attenuates radiation.
As with other methods of point measurement,
siting in a representative location is critical for
interpreting and applying point measurements as
areal indices.
The gauges used to measure total water content
consist of a radiation detector and a source, which
is either natural or artificial. One part (for example,
the detector/source) of the system is located
at the base of the snowpack, and the other at a
height greater than the maximum expected snow
depth. As snow accumulates, the count rate
decreases in proportion to the water equivalent
of the snowpack. Systems using an artificial source
of radiation are used at fixed locations to obtain
measurements only for that site. A system using
naturally occurring uranium as a ring source
around a single pole detector has been successfully
used to measure packs of up to 500 mm of
water equivalent, or a depth of 150 cm.
A profiling radioactive snowgauge at a fixed
location provides data on total snow water
equivalent and density and permits an accurate
study of the water movements and density
changes that occur with time in a snowpack
(Armstrong, 1976). A profiling gauge consists of
two parallel vertical access tubes, spaced
approximately 66 cm apart, which extend from a
cement base in the ground to a height above the
maximum expected depth of snow. A gamma ray
source is suspended in one tube, and a scintillation
gamma-ray detector, attached to a photomultiplier
tube, in the other. The source and detector are set
at equal depths within the snow cover and a
measurement is taken. Vertical density profiles of
the snow cover are obtained by taking
measurements at depth increments of about
2 cm. A portable gauge (Young, 1976) which
measures the density of the snow cover by
backscatter, rather than transmission of the
gamma rays, offers a practical alternative to
digging deep snow pits, while instrument
portability makes it possible to assess areal
variations of density and water equivalent.

6.7.6 Natural gamma radiation
The method of gamma radiation snow surveying is
based on the attenuation by snow of gamma radiation
emanating from natural radioactive elements
in the top layer of the soil. The greater the water
equivalent of the snow, the more the radiation is
attenuated. Terrestrial gamma surveys can consist
of a point measurement at a remote location, a
series of point measurements, or a selected traverse
over a region (Loijens, 1975). The method can
also be used on aircraft. The equipment includes
a portable gamma-ray spectrometer that utilizes a
small scintillation crystal to measure the rays in a
wide spectrum and in three spectral windows
(namely, potassium, uranium and thorium emissions).
With this method, measurements ofgamma levels are required at the point, or along
the traverse, prior to snow cover. In order to obtain
absolute estimates of the snow water equivalent, it
is necessary to correct the readings for soil moisture
changes in the upper 10 to 20 cm of soil for
variations in background radiation resulting from
cosmic rays, instrument drift and the washout of
radon gas (which is a source of gamma radiation)
in precipitation with subsequent build-up in the
soil or snow. Also, in order to determine the relationship
between spectrometer count rates and
water equivalent, supplementary snow water
equivalent measurements are initially required.
Snow tube measurements are the common reference
standard.
The natural gamma method can be used for
snowpacks which have up to 300 mm water
equivalent; with appropriate corrections, its
precision is ±20 mm. The advantage of this
method over the use of artificial radiation sources
is the absence of a radiation risk.

nilhg

1. DEC IMT will be 4.6C
JAN IMT will be 4.1C
FEB IMT will be 5.0C
average 4.8C

2. DEC precip will be _99__ %
JAN precip will be _81__ %
FEB precip will be __110_ %
(average -- see above)

3. Max temp for the three months __14.2C___
Min temp for the three months ___-7.8C__

4. Highest wind gust in knots _48___ kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar ___5.9cm______

OPTIONAL comments ________________________

oterra

1. DEC IMT will be 5.1
JAN IMT will be 4.1
FEB IMT will be 4.3

2. DEC precip will be 80%
JAN precip will be 105 %
FEB precip will be 110 %

3. Max temp for the three months 14.2c
Min temp for the three months -12.2.c

4. Highest wind gust in knots: 70 Knots

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 29cm

waterways

1.
DEC IMT will be 4.7
JAN IMT will be 1.7
FEB IMT will be 3.9

2. DEC precip will be 94 %
JAN precip will be 83 %
FEB precip will be 149 %

3. Max temp for the three months 14.9
Min temp for the three months -15.9

4. Highest wind gust in knots 60 kt

5. Snowfall in cms at Casement for period 1 Nov to 31 Mar 10.3