8th annual winter forecast contest (2017-18)

WELCOME to the 8th Annual Winter Forecast Contest. The rules will be similar to past years ...

The deadline will give you a chance to peer into the first week of December with some idea what's going on as the season starts. In weather circles, winter is December, January and February, and that will be the basis of our contest. Read the rules carefully and feel free to enter any time before the deadline ...

Entries accepted until 0300h Friday 8 December with a possible extension of no more than 48h depending on number of entries and how I assess the fairness of that extension. I will be away (moving) until almost then, so look for a table of entries after I close the contest to further entries.

The top scores in past years were close to 75/100 to give you some idea of what the standard is. Here are the rules, look at the end of this post for a template that you can use to enter. I will make an effort to review all entries and contact anyone who has an incomplete entry. It's up to you to be familiar with the rules in each question.

(1) For each month Dec Jan Feb, predict the "IMT" which is the Irish Mean Temperature, a statistic developed on this forum by Deep Easterly, and the average of five stations in central inland locations (Shannon, Oak Park, Mullingar, Casement, Claremorris). For newbies, this is the average of daily highs and lows. Over recent 30-year periods, the means have been around 5.4 in Dec, 5.3 in Jan and 5.2 in Feb. Very mild months would run around 8-9 C and very cold ones a little below freezing (Dec 2010 was -0.4). These forecasts generate 5 points each, and the seasonal average, which you don't need to calculate (I do that from your entries) counts for 15 points.

(2) For each month Dec Jan Feb, predict the monthly precipitation as a percentage of normal values. This is calculated as in our monthly forecast contest, from records taken at eleven stations that report in the Met Eireann Monthly Summary. Those are the five mentioned above plus Valentia, Cork, Johnstown Castle, Belmullet, Ballyhaise and Malin Head. Note that Dublin is not included. Values under 50% are considered exceptionally dry and above 200% exceptionally wet (for your guidance). The scoring for these three forecasts and the seasonal average which again you don't need to enter, will also be 5,5,5 and 15 points.

(3) For all the reporting stations of Met Eireann, as reported in their Monthly Summary, predict the seasonal highest and lowest temperatures. This will apply only to dates from 1 Dec to 28 Feb for the max, but can apply to dates both before and after the winter for the min (up to 15 April when the contest results are declared). The max in the past three winters has been close to 15 and the min during the first contest was about -16 but then more like -6 in the second contest, -8 winter of 2012-13, and similar values the past two winters. I would guess the long-term average for the winter minimum is around -8 to perhaps -10. These two predictions are worth ten points each.

(4) Predict the seasonal snowfall (in cms) at Casement. This will run from the first measurable snowfall (your forecast should include anything already reported if it does snow in November, check this thread and elsewhere for updates on that) to 15 April (anything after that won't count as the contest is over on 15 April). These daily snowfall values (if they occur) are measured at hourly intervals and summed, which means the snow depth at any point might not be quite as much as the snowfall amount. However, amounts vary a lot from season to season. In the first contest winter 2010-11, there was about 50 or 60 cms but then we used a stat from Boards member "Danno" in Laois who had about 30 cms. In 2011-12, I believe there was almost zero accumulation and our lowest contest guess had the highest score. This was similar to the past four winters when most of the field guessed higher than what actually fell at Casement (something like 7 cm in 2012-13 and 3 cm in 2013-14 and 2 cm in 2014-15, 3 cm in 2015-16, almost nothing last winter). This part is worth ten points.

(5) Finally, predict the highest wind gust in knots at any reporting station in Ireland as per the Met Eireann Monthly Summary, but note that in this case, the period is only the three winter months -- strong winds in November or March or early April won't count, the gust has to be between 1 Dec and 28 Feb. Knots are almost double km/hr and about 1.15 times mph. Values between 70 and 100 knots are most likely to verify from climatology, the extreme range would be about 50 to 120 for this statistic. This part is also worth ten points.

Note: All scores are based on rank order, not absolute differences from prediction to actual values. This equalizes the various sections of the contest and distributes the scores evenly. Once we establish the number of entries, I will update this scoring system, but basically, 10% of the entries get top scores in each category and then on down, with any odd numbers left over getting the zero scores. Where it's 10 points, the gradations are 10,9,8,7,6,5,4,3,2,1,0 and where 5 points, half of those values, where 15 we will give equal numbers of scores, and let you know later how many will share each score (based on number of entries).

So, here's the template, once you understand what to predict, just change all the letters here to number values and block copy, submit along with your comments etc. We're open for entries although you'd be smart to wait until near the end of November or the first of December. You can edit your post without notifying me at any time up to whenever you see the entries cut off announced and a table appearing in the thread. I don't work on that until the cut off, so edit at will, I won't know except for the forum software making a note of it.

TEMPLATE FOR ENTRIES

DEC-IMT
JAN-IMT
FEB-IMT

DEC-PRC
JAN-PRC
FEB-PRC

MAX TEMP C

MIN TEMP C

SNOW cms

GUST kts

(all temps can have one decimal place, prc % to nearest whole number, snow can also have one decimal place, gust to nearest whole number)

Good luck and check back, also, if you are new to our contests, check out the December monthly contest when it's announced in the last few days of this month. We do those every month.

(Use this template if at all possible)

0.0 _ 0.0 _ 0.0 ___ 100 _ 100 _ 100 ___ 10.0 _ -10.0 __ 00.0 ___ 00

This will be my entry unless I decide to edit it before the deadline:

4.5 _ 4.2 _ 5.5 ___ 080 _ 120 _ 100 ____ 15.7 _ -11.5 _ 32.5 (cm) __ 80 (kts)

Note -- I will take the consensus values of the entries, and report on that in the winter 2017-18 thread as the "Boards consensus forecast" so be a part of that.

Defending champion is DOCARCH.