METAR history
 

I've got several links to sites which give you the current METAR/TAF but what I'm after is a site which will give you previous METARs.
Something like a list of the last 24 hours etc.
Thanks,
H-D :)

ADDS - METARs :ok:

Metar altitude
 

What is the significance of the two altitudes given on METARS for US locations? One is called "sea level". What is the other?

If you mean Altimeter the first one is pressure at the airport elevation, the second one is pressure at sea level.

That is a question nobody has been able to answer to me.
Actually it can not be the pressure at the airport. Take a look at this METAR from Denver International.

KDEN 142153Z 02013G16KT 10SM SCT090 BKN140 BKN220 34/M04 A2999 RMK AO2 SLP061 T03391044

It says the altimeter setting is 29.99 inches of mercury. We all know that altimeter setting ( or QNH) is the station pressure corrected to sea level. Station pressure is called QFE and in the case of Denver (5200 feet MSL) it would be somewhere around 24 inches of mercury or 870 milibars. It is impossible to have 29.99 at 5200 feet ( field elevation).

If you continue reading, in the remarks section it says SLP (Sea level Pressure) 061, which means 1006.1 milibars or hectopascals. And that, of course, it is not the conversion from 29.99 inches.
So what does SLP mean in US Metars?

AC00-45 Aviation Weather Services say "some stations include the sea-level-pressure, which is different from altimeter".

One of the most useful sites for past information is
Plymouth State Weather Center 24-HR Surface Station Summary Generator

If A29.99 is set on the aircraft altimeter at the time of the observation then the altimeter will read the airport elevation not zero or any other number, so it is the pressure at the airport. And we all know SLP is sea level pressure.

helen from Hades
 

How's the heating;)?

Quick way is go to Welcome to Weather Underground : Weather Underground (.wunderground.com) input location (pref 4 ltr code) & you can get historical Metars for any location that publishes same. I find this quicker than going through the main met databases/offices preamble is faster.

But a very short stationlist. You don´t even find Ljubljana on the list :zzz:

WX Support gives METAR history, not for 24 hours, but the last 5, quite nice showing recent trends. I use it a lot.

One option here:

Observations EGLL Centre Meteo Montreal

Above is an example, Heathrow for the previous 48 hours. For any other airport edit the ICAO code in the url. '048' is hours back which can also be edited.

Also this site: Formulario para peticion de mensajes aeronauticos

University of Wyoming site here works pretty well, interactive map etc......

Station Observations

Also allows you to look back up to a month, choose date/time etc

Internet Weather Source from the NWS and NOAA gives current METAR and past 24 hour summary.

IWS International Weather Conditions


VRSC :ok: