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WxChallenge 2013-14


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How can you explain that the metar has failed by reporting its normal and usual report 51-56z past the hour? There was no error in the report, it had 29F for the lowest at that time. The quality of the report was also deemed good since the ASOS was not in error either. And I've said before, either revise the rule or come out and say "we're going with the climo report for specific reasons explained here" Don't just go against one of the rules that is in place for things like this and say nothing about why. And Mallow, don't just say the METAR failed because it comes out before 6z otherwise put in a petition to make all METARs report at exactly 6z.

 

You seem to be stuck on the idea that "fail" MUST mean "mechanical failure". I don't see it that way. The METAR "failed" in this instance in the sense that it failed to capture the 06z-06z. In other words, it "failed" to record the low that the WxChallenge forecasters are "supposed" to be forecasting for.

 

In fact, I'd say that based on the various bullet points they have listed, my interpretation is the correct one. They aren't going against the rules, your interpretation is.

 

  • Forecasts are due Monday evening through Thursday evening at 00 UTC (technically, Tuesday-Friday) and are valid for 06 UTC until 06 UTC for the following day. Each forecast consists of a high temperature (in F), a low temperature (in F), maximum wind speed (in knots; not gusts), and a cumulative liquid precipitation measure (in inches) for that forecast period.
  • If a METAR observation has a temperature greater than the climatological report high, a temperature less than the climatological report low, a wind value greater than the climatological report values, or the climatological report is missing or deemed to be invalid, then the METAR values will be used. The precipitation verification (liquid or solid) will come from the standard 06-06 UTC METAR reports. These standard reports (not special observations) typically run between 51 and 56 minutes past the hour and will have the 6-hour codes included. Any precipitation falling after the standard 06 UTC METAR observation (even if before the 06 UTC time) will count toward the next forecast period. The climatological report will only be used as a backup if the ASOS fails and is unable to report precipitation. Care must be taken to ensure that the climatological values represent the forecast period since those reports are issued midnight to midnight local time and not 06 UTC to 06 UTC.

Note that they specifically mention that the precipitation comes from the standard "06z" METAR reports, but not the temperatures. Also note that they mention the METARS can be used to INCREASE a high, DECREASE a low, or INCREASE the wind from the climate report, not the other way around. That strongly implies that this situation was foreseen and handled exactly as it should have been. The climatological report told us that the low was 28F BEFORE 06z. The METAR "failed" to give us that extra information. And the forecast is for the 06z-06z period.

 

This is all clearly a technicality (either way), because NOBODY was forecasting 28 or 29 based on the idea that those 7 minutes between 0553z and 0600z would make that difference. Someone who put 28 wasn't thinking "well, it will be 29F at 0553z, but will fall to 28F before 0600z, and the rules state that the 28F will count." Likewise, someone who put 29 wasn't thinking "well, it will be 29F at 0553z, but will fall to 28F before 0600z, and the rules state that the 29F will be the result." The interpretation of the rule would not have caused anybody to change their forecast. Which is why I'm really fine whether they keep it 28 or change it to 29. But I very much disagree with your assertion that they're not following the rules... in my opinion, it is your interpretation of the rules that doesn't really hold up under scrutiny.

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Mallow, it failed to capture the low because it was designed to report back 53 past every hour, therefore its a design failure which is human error not metar error. You are saying it failed to capture the true low, but how can it fail to do so when its programed to capture the low 53 past every hour to begin with. By design it didn't fail and unless there is a specified passage about the design flaws of a metar report the low should be 29 for day 3. 

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Mallow, it failed to capture the low because it was designed to report back 53 past every hour, therefore its a design failure which is human error not metar error. You are saying it failed to capture the true low, but how can it fail to do so when its programed to capture the low 53 past every hour to begin with. By design it didn't fail and unless there is a specified passage about the design flaws of a metar report the low should be 29 for day 3. 

 

Again, "fail" is not relegated to "mechanical failure". The 53-past is not a design flaw, either. WxChallenge is not affiliated with NOAA and they did not design the sensors or the software to send the data.

 

The point is, WxChallenge has designated the 06z-06z period as the period to forecast for temperatures, not the 0553z-0553z period. So if a METAR that comes out at 0553z doesn't actually capture the lowest temperature in the 06z-06z period, it has failed to report the low for the period that the WxChallenge has designated as the forecast period for temperatures. The METAR hasn't "failed" from the perspective of NOAA or the NWS, it has only "failed" from the perspective of WxChallenge and its rules. I don't know how I could make this any clearer.

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For what it's worth, if you ask me what I think SHOULD be the rules, it would be that all three of high, low, and precip should use the METARS, not the climate report. There are many potential flaws with the way they have it set up now. For example, the 12z METAR could have a low lower than the climate report because the low happened between 0553z and 0600z of the "previous day", and the lower (METAR) value would be counted according to the current rules. In other words, the way they have it set up for temperatures actually gives the "06z-METAR to actual-06z-of-the-following-day" values. Which is silly.

 

But the way their rules are currently worded definitely implies that the "low" should be 28F for day 3, at least as I interpret it.

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I don't know why I care so much, I'm an alum nothing counts for me anymore. Probably only thing I care about now is getting the precipitation correct when I forecast since it usually is harder to get and counts towards more error usually. Well, I used up my "one eff/yr"  :lmao: time to move on  :hug:

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For what it's worth, if you ask me what I think SHOULD be the rules, it would be that all three of high, low, and precip should use the METARS, not the climate report. There are many potential flaws with the way they have it set up now. For example, the 12z METAR could have a low lower than the climate report because the low happened between 0553z and 0600z of the "previous day", and the lower (METAR) value would be counted according to the current rules. In other words, the way they have it set up for temperatures actually gives the "06z-METAR to actual-06z-of-the-following-day" values. Which is silly.

 

But the way their rules are currently worded definitely implies that the "low" should be 28F for day 3, at least as I interpret it.

 

 

Agree. The same could be said for the wind. The climate report inlcudes the highest winds for the day, 12am -12am local time. However, the 6z to 6z period could be 11pm to 11pm for example in a West Coast city such as Seattle. Therefore, the climate report includes winds for the hour after the 6z-6z start and the first hour after 6z-6z period ended. Thus, the highest winds could be included in the scoring even though they occurred in the wrong period.

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Agree. The same could be said for the wind. The climate report inlcudes the highest winds for the day, 12am -12am local time. However, the 6z to 6z period could be 11pm to 11pm for example in a West Coast city such as Seattle. Therefore, the climate report includes winds for the hour before 6z-6z start and the first hour after 6z-6z period ended. Thus, the highest winds could be included in the scoring even though they occurred in the wrong period.

 

Only problem with the wind is that the peak wind is not recorded in the METARs like the peak temperatures and total precip are.

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58/34/17/0

 

Undercut MOS a bit...it seems to be running a bit warm overall based on last week, especially for highs. Raw guidance and NWS were also cooler than MOS, but with sun and CAA subsiding tomorrow should run several degrees warmer than the 52 they did today. Shot low on the min tonight, but if stay fairly clear and winds subside they should be able to do low to mid 30's I'd hope. Picked an arbitrary number for wind, still a bit of a gradient but not really strong so hopefully they aren't doing 25+ knots tomorrow like they did today.

 

Finished at 300 after last week...not great but hey something to build on...top 150 for Cheyenne would be nice.

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I'm nervous about that 34 low, it was risky given the winds and potential overcast conditions tonight. However, it doesn't take long for the temp to plunge and the winds/clouds should let up before sunrise.

I have the same forecast as you and and weatherMA :P I'm thinking 34 was probably too low though. Mostly cloudy and held at 47F this last obs. :axe:

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Should have stuck with 60/40/20/0 (though I wouldn't COMPLETELY rule out the possibility of dropping below 39F this evening).

 

EDIT: Or not. 39F at last observation.

 

37F between hourlies. Nice. Now I'm definitely glad I didn't go 60/40/20/0 :P

 

Liking the winds. I really hope the high manages 60F. It's going to be between 58 and 60... hopefully the higher end! If it's 60F for a high, depending on the wind, I'll be somewhere between 5th and 7th place so far. If it's only 59F, I can still be as high as 11th.

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Already 57 as of 1853z (1253 local time)...only like 80 people forecasted a high greater than 59 so those people should really move up. Also the wind is already at 18kts and only about 65 people forecasted above 20kt winds...so looks like a tough day overall! Glad the low fell to 37 at least instead of 39.

 

Everyone is doing well on precip though! ;)

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