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20011211: METAR weather codes again

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  • Subject: 20011211: METAR weather codes again
  • Date: Tue, 11 Dec 2001 13:10:17 -0700
Scott and Steve,

Yesterday I mentioned the metar decoding of BR and MIFG
being apparently transposed.

Today, the question is in classifying the metar ofservation of FG.
(From the quick reference card, I find that BR has visibility
>= 5/8 SM, and FG is < 5/8 SM).

In PT_WNMT, BR and FG decode to the same weather number
which equates to the 2 bar fog symbol. The WMO code table 4677
provides for 10 as "Mist" which describes BR. The question is whether
FG with visibility <5/8SM should be represented by the 3 bar
(WMO code 45) symbol. Or, would that be +FG....which would
still be decoded as 2 bar fog?

If you have any feelings on this, I'd be happy to hear them.

Steve Chiswell
Unidata User Support