PPRuNe Forums - View Single Post - Met Office Weather Forecast? Hmmmmmmm....
Old 21st Jun 2008, 21:51
  #69 (permalink)  
bookworm
 
Join Date: Aug 2000
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So once again you're taking a single METAR and comparing it with a 9-hour TAF. Here's the full sequence.

METAR EGPH 211620Z 13012G23KT 9999 -DZ FEW030 13/07 Q1013=
METAR EGPH 211650Z 13011KT 9999 -DZ FEW025 BKN045 12/07 Q1013=
METAR EGPH 211720Z 11009KT 9999 -RA FEW025 BKN045 11/08 Q1012=
METAR EGPH 211750Z 10009KT 9999 -RA OVC035 11/08 Q1011=
METAR EGPH 211820Z 09011KT 9999 -RA FEW018 SCT026 BKN035 10/08 Q1011=
METAR EGPH 211850Z 09011KT 9999 -RA FEW016 BKN030 09/07 Q1010=
METAR EGPH 211920Z 08011KT 9999 -RA FEW009 SCT020 BKN026 09/07 Q1010=
METAR EGPH 211950Z 08011KT 9999 -RA FEW009 SCT012 BKN018 09/08 Q1009=
METAR EGPH 212020Z 07013KT 6000 -RA FEW008 SCT010 BKN016 09/08 Q1009=
METAR EGPH 212050Z 08014KT 9999 -RA FEW006 SCT009 OVC014 09/08 Q1008=

You complain about the lack of mention of an 11 knot gust. Bear in mind that gusts of up to 10 knots are neither recorded nor forecast. The mean wind speed is spot on. The direction is backing to the forecast direction for the period of the forecast, and unless you want TAFs to get even longer than they are, you'll have to accept some variation in wind direction around the mean.

Weather does vary, and it sometimes varies in an unpredictable way. The appearance or absence of showers at a particular spot is a probabilistic phenomenon, like the appearance or absence of bubbles in a particular place in a boiling pan.

Met Office forecasters do sometimes get it wrong. Most of the time, they get it right, or at least as right as can be expected for any prediction of local meterorological conditions. Picking out single METARs is not a fair way to assess overall forecast performance.
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