A couple more on the METAR, insertd below
________________________________ From: Carleton MacDonald <[email protected]> To: U.S. Metric Association <[email protected]> Sent: Fri, April 23, 2010 11:29:34 PM Subject: [USMA:47255] Re: Air flight altitudes in meters PK WND 26027 - peak wind 260 degrees, 27 knots, observed at 0109 UTC SLP179 - Sea Level Pressure 1017.9 hPa, the leading "9" or "10" is omitted. It is calculated by a different algorithm than the alitimeter setting which is also a "sea level pressure". For low altitude airports, they agree closely. T01280083 - two 4-digit temperature fields, dry bulb and dewpoint, °C to nearest 10th, leading zero for positive numbers, leading 1 for negative. This value is 12.8 °C dry bulb, 8.3 °C. In spite of the apparent precision, these (almost) always represent whole Fahrenheit degrees converted to nearest tenth, Celsius, because of equipment limitations. More: http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=mtr&sid=KSFO&num=48&raw=0&; dbn=m It's still an inch-pound world out there in US aviation. Correction below ... Current weather for San Francisco International Airport: KSFO 240156Z 26016G22KT 9SM BKN012 13/08 A3006 AO2 PK WND 26027/0109 SLP179 T01280083 KSFO - San Francisco International Airport 240156 - April 24, 0156 UTC ("Zulu") - 1856 local time April 23 (PDT) 26016G22KT - Wind from 260 degrees (west-northwest), 16 knots, gusting to 22 knots 9SM - visibility 9 statute miles BKN012 - cloud cover broken, ceiling 1200 ft (broken means clouds with a few holes - that is, the famous San Francisco fog is in) 13/08 - The temperature, in Celsius (!), followed by the dew point temperature, in Celsius A3006 - altimeter setting/barometric picture is 30.06 inches of mercury A02 - reported from an automated station - no humans, also defines capability of the station
