May 2021 Boards weather forecast contest

Tae laidir · 03-05-2021 10:45am

Markee Castle -2.7 again yesterday.

pauldry · 03-05-2021 11:32am

Met Eireann forecasting -3c Wednesday night so could possibly go lower again.

appledrop · 03-05-2021 11:36am

pauldry wrote: »

Met Eireann forecasting -3c Wednesday night so could possibly go lower again.

Pauldry could you ask Met Eireamn to arrange it to be -3 exactly?

I might get some points then this month after my dismal score of nil points for my min prediction last month!

appledrop · 06-05-2021 6:22am

Mt Dillion -4 at 6am.

M.T. Cranium · 06-05-2021 7:49am

Looks like I could score MIN already on the 6th LOL. Minimum progression required. Will retain the 2 point augmented late penalties as there probably was a slight advantage and the two people getting that will be scoring well on MIN.

Will go with 20, 20, 19, 18 etc, doubling up also at 15, 10 and 5, that should get us down to 1 point for mildest forecast. Ties may make it a bit uneven and I may even things out where the values are not evenly spaced, wait and see on that but otherwise you can pretty much figure out your MIN score now.

Gonzo and waterways (-3.2) to get 20 (Gonzo really 18 due to the augmented late penalty).

Appledrop (-3.0) 19, Danno (-2.8) 18, adam240610 (-2.5) 17 (net 15) JPmarn (-2.5) 17.

MrSkinner (-2.3) 15, Pauldry (-2.3) 15, sunflower3 (-2.2) 14, dasa29, bsal (-2.0) 13.

Artane2002, DOCARCH, dacogawa, Cirrus Business and consensus, (all -1.8) 11.

MrStonewall (-1.6), john mac (-1.6) 8.

M.T.Cranium, tae laidir, Joe Public (all -1.5) 6.

Kindred spirit (-1.4) 4, 200motels (-1.3) 3.

sryanbruen (-1.1) 2, NormaL (-1.0) 2, western storm (0.0) 1.

Jpmarn · 06-05-2021 8:02am

The -4°c report in Roscommon (Mt Dillon) was mentioned on the Radio 1 7.55 weather forecast.

DOCARCH · 07-05-2021 8:14am

Mount Dillon confirmed at -4.0c yesterday.

pauldry · 07-05-2021 8:53am

Yes and that will likely be it for May.

Tomorrow 18c!!

M.T. Cranium · 07-05-2021 5:54pm

Full weekly report tomorrow but IMT on 6.6 after six days, and yesterday's average was 4.9, about normal for this time in Jan or Feb.

Jpmarn · 07-05-2021 11:16pm

pauldry wrote: »

Yes and that will likely be it for May.

Tomorrow 18c!!

19°c has been indicated for the Dublin area on the TV after the RTÉ ONE 9 O’clock News.

M.T. Cranium · 08-05-2021 7:17am

There appears to be a fairly wide "dry slot" so there may be enough sunshine to boost temperatures to 21.3 and end the suspense -- that 552 dm thickness is making a brief visit. Another scoring task ending ahead of schedule? We shall find out. Would suspect Gurteen or Moorepark might do the business as they will have longer intervals of sunshine possibly.

appledrop · 08-05-2021 8:02am

It's currently lashing rain and 6 degrees at Dublin airport.

However it is meant to take up so who knows what will happen.

It is reading 13 degrees at 7am at Moorepark , if that is correct.

appledrop · 08-05-2021 7:32pm

Turned into a beautiful day eventually in Dublin.

Maxed out at about 18 degrees so April max is not beaten yet.

Great to actually feel the heat of the sun again!

M.T. Cranium · 08-05-2021 9:21pm

After the first week ...

IMT 6.5 C which is 3.8 below normal. That is probably around 7.4 now though.

MAX will be today's value, will edit that in tomorrow (18-19)

MIN was -4.0 and so scoring has already taken place (see previous post).

PRC was 145% at midnight but another 10-15 mm fell earlier today, getting week two off to a healthy start. The amounts so far would probably equate to half the average monthly total.

SUN has made a good start at 130% (878/600).

appledrop · 09-05-2021 8:28am

19.2 new Max on 8th at Phoneix Park.

M.T. Cranium · 09-05-2021 9:48pm

I hear there's a popular park in Beijing called Phone-Xi park.

M.T. Cranium · 10-05-2021 7:33am

Looking ahead it's hard to see where it would get any warmer now, the IMT may drift up slowly with the cloudy nights but daytime highs are going to remain in a fairly low range now. If that was the month's high then good old Minnie Progression may get another call.

M.T. Cranium · 15-05-2021 9:49pm

After two weeks ...

IMT is 8.3, second week was 10.2 C, still 0.7 below normal for 8th to 14th. Today's 12z GFS run gives some hope for warming in the fourth week, we will likely still be close to 8.5 by then, and could then steadily rise towards 10.5 or a bit higher for the outcome. However, some recent runs have not been as optimistic and we would struggle to reach even our lowest IMT forecast of 9.8.

MAX was 19.2, MIN -4.0 and already scored as that was below all forecasts. MAX likely won't change this coming week but could go into the 20s eventually.

PRC is now 170% with the second week a soaking 194% of normal. Third week looks about as wet as we've had it so far, then fourth week a bit drier, outcome could be around 140%. Only three forecasts went that high (I went 150%, dacogawa 142%, Kindred Spirit is at 140% and sryanbruen at 130%). There could be a "modified minimum progression" situation developing unless there is so much rain that it blows past 157% (then my raw score drops to 12 or below and full boost kicks in). No big gaps below 150% so somebody would trigger the reduced version for sure.

SUN finally took some time off, in some places anyway, and is now at 113% with the second week at 96% (574/600), mainly due to Valentia being quite cloudy, the other five locations averaged about 110%. This coming week looks quite cloudy but the fourth week at least on today's model run looks more average. The net change would be back down towards 100%, possibly lower. Our lowest forecast was 75% and our highest 120%.

On the matter of the bonus question, the one day we had any chance of breaking 21.2 was last Saturday and that fell short, the next opportunity from today's model run and using the 552 dm thickness modified by solar angle now to 549 dm, appears to be ... calculating here ... 24 May. (omg) If so, that would fall into third last place in the table of guesses (we have a 26th and a 30th, several said 23rd and would share the ten points if this verifies, or even if it's 25th, at 26th I think I would go 10 for the 26th guess and 9 for all of the 23rd and 30th guesses and work down from there to be fair. Of course, that's today's revised version of the model run, I check them daily for the forecasting and they have been bouncing back and forth for days now between no warming trend at all to a considerable warming after the 23rd, no hunch as to which is correct. If we go later than 26th then 26th and 30th will get ten, the 23rds will get 9, etc.

M.T. Cranium · 16-05-2021 9:25pm

Rules for minimum progression. I think these were spelled out once or twice over the years, worth repeating them for general interest.

(1) Minimum progression is used only when one-third or more of the contest entrants score zero, or when the entire run of scores is lower than usual. The normal application is to take the best forecast and award that one maximum points or one fewer if the forecast scores zero. Then the rest of the field are awarded points in rank order with one point the end of the progression unless the start is one short, then zero is the end point.

(2) If these conditions apply but one or more forecasters have raw scores within two of the maximum allowed in the category, then "reduced minimum progression" is used, that being the same as above, compared to raw score, and an average taken. (example, in normal minimum progression the forecast would score 10, the raw score was 2, then the reduced minimum progression score is 6).

(3) Contest scorer has the option of modifying the progression to fit any discontinuous run of forecasts for fairness, for example, if there were MIN temp forecasts in the middle of the run that went -6, -4, -2 and most of the guesses were either close to -6 or -2, then the progression might run something like 20, 19, 18, 17, 17, 16, 16, 15, 15, 14, 14, 10, 6, 6, 5, 5, 4, 4, 3, 3 etc to reflect the forecast differences. I can't remember using this concept except in some minor applications like deciding where to double up the scores.

(4) No score(s) will be lower from minimum progression than the raw score achieved. This has been invoked in cases where there were no high scores but most forecasts were in the low end of the raw scoring range.

and just a note on why minimum progression is used at all, since it tends to maintain the same general scoring differentials within the month ... it equalizes monthly scores so that for our best 10 of 12 scoring format, we aren't all dropping the same two months.

Jpmarn · 17-05-2021 2:38am

Models are showing a substantial chance that the 21.2°c barrier may not be breached by the end of the month. If it happens it would likely to be in the last few days of the month. My present guess would be the 28th at the moment. I am not trying to influence my entry as that was based on my guess then.

M.T. Cranium · 17-05-2021 6:12am

Certainly unlikely to come before the 24th and could be delayed to the end of the month or beyond, model runs keep changing the look of the last week but that in itself says no strong signal for warming. Once it reaches the 25th the outcome will be the same for the contest scoring anyway.

pauldry · 17-05-2021 8:53am

At this rate the minimum progression will be used for just about everything!!

M.T. Cranium · 17-05-2021 8:51pm

I think IMT will be scorable, MAX could be, only takes that one warm day. PRC is not getting too far out of control either, GFS ten-day looks just a bit higher than average to 27th, and that's lower than we are now. Sunshine could start running up against the lower end of our range but even if it fell to 80% there would be no need for boosted scores (would probably just call the outcome 80% for anything lower and score from there).

Tae laidir · 18-05-2021 5:55pm

It's possible that warmest day in April and May could be April 1st.
Quelle Spring!

appledrop · 18-05-2021 7:06pm

Tae laidir wrote: »

It's possible that warmest day in April and May could be April 1st.
Quelle Spring!

Now that would be mad, only in Ireland!

Joe Public · 18-05-2021 8:58pm

Tae laidir wrote: »

It's possible that warmest day in April and May could be April 1st.
Quelle Spring!

My money is on the last day of May

M.T. Cranium · 22-05-2021 6:47pm

After three weeks of (thinks for a minute) May?!? ...

(are we now in the southern hemisphere?)

IMT 8.9 with the third week 10.0 (1.4 below normal). This looks set to edge up a little towards a 9.5 finish.

MAX still 19.2, MIN -4.0 (already scored). Still some chance of outdoing the current MAX and about 50-50 chance for making it to 21.2 (but fairly soon the scoring would be the same whether we do so or not, 24th is the last date for 21.2 to make any difference to scoring).

PRC is now guaranteed to reach 136% even if nothing more fell, but more will of course fall, the current value is also 196% of normal with the third week 247% of normal. With a somewhat drier outlook this will still finish higher than 150% (the highest forecast) but how far above will determine the type of boost to scoring.

SUN is at 102% of normal with the third week at 81.5%. There probably won't be much change now to the final value with some partly sunny days in the mix despite a lot of cloud tomorrow and Monday.

pauldry · 25-05-2021 1:43pm

So you predict 18 to 21c from Saturday to Monday MT. But will it be 21.2c?

M.T. Cranium · 25-05-2021 5:38pm

Have seen some warmer guidance today, but as we are probably not going to see 21.2 until near the end, here's the scoring for the bonus question if first 21.2 is 27th to 31st (or June) ... if it reaches 21.2 tomorrow, same except that 30th (Danno) moves to the 9 group:

10 pts _ Danno 30th, Cirrus Business 26th, waterways 25th

9 pts __ john mac, Gonzo, appledrop (all 23rd)

8 pts __ Mr Skinner, Pauldry (both 22nd), sunflower3 (21st)

7 pts __ tae laidir, dasa29, 200motels, Adam240610 (all 20th) also Con Sensus

6 pts __ sryanbruen, MrStonewall (19th)

5 pts __ Kindred Spirit, bsal (18th)

4 pts __ Artane2002, M.T. Cranium (16th)

3 pts __ Joe Public (15th), dacogawa (14th)

2 pts __ JPmarn (13th), NormaL (13th), DOCARCH (12th)

1 point _ Western Storm (10th).
_________________________________

will give Danno or others at 10 pts 1 or 2 superbonus points for hitting date on the nose (2) or within one (1) so only the 28th or no outcome in May would go unrewarded in that regard.

M.T. Cranium · 27-05-2021 10:56pm

Any ideas for a bonus question for the June contest? My mind has gone entirely blank after wrestling with data files for the past two days. Are we even sure it is May? It looks like May outside here, the cottonwood snow is starting up.

May 2021 Boards weather forecast contest

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