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The 3rd Axis
2nd Aug 2002, 08:31
Hi All

Just browsing Reporting Points, in particular the B727 crash in Florida. Some weather information was posted.

KTLH 261053Z 00000KT 9SM FEW001 SCT015 SCT150 BKN250 22/22 A3013
RMK AO2 SLP200 VIS SW-NW 1/2 CB DSNT SE CB DSNT SW FU SCT015
FU PLUME OVR APCH RWY 09 T02220217=
KTLH 260953Z 00000KT 8SM FEW001 SCT150 SCT250 22/22 A3011 RMK AO2
SLP195 T02220217=
KTLH 260853Z 12005KT 9SM FEW001 SCT180 SCT250 22/22 A3010 RMK AO2
SLP192 T02220217 55003=

While I see many similarities to the weather presentation in my part of the woods, some things are different :(

After the date/time group on line 1, what is "9SM", and on the finish of line 1, "A3013"
On line 2, after the Remark, "A02 SLP200" and "CB DSNT SE CB DSNT SW FU"

Could someone please explain these elements, and I am sure the others in the weather I can work out from there. :D

The 3rd Axis

Field In Sight
2nd Aug 2002, 08:52
Mostly differences due to US use of Imperial measurements.

Look here.
http://www.n0esg.com/decodemetar.htm

chiglet
2nd Aug 2002, 08:53
At a guess, 3013 is the Pressure Setting [QNH] in inches
9SM 9 Statute Miles? FU is SMOKE
Visibilty in [Quadrant] SW-NW 1/2 Mile vis CB in the distance?
I might be talking boldocks, but I hope this helps a bit
we aim to please, it keeps the cleaners happy

Fokker-Jock
2nd Aug 2002, 10:47
Weather at Tallahassee Regional

Date: The 26. of the month at time 10:53 GMT
Wind: 000 degrees at 00Kts
Visibility: 9 Statute Miles
Clouds: Few at 100 feet, scattered at 1500 feet, scattered at 15000 feet, broken at 25000 feet.

Temperature 22, dewpoint 22
Altimeter: 30.13 InHg

Remark:
A02 = recorded by an automated station with precipitation measurement capability
SLP= Sea level pressure = 200 tenths of a HPa more than reported at the station.
VIS= visibility in SW-NW sector 1/2 SM
CB observed more than 10 miles away from station (DSNT=Distant) towards the SE, and CB observed more than 10 SM towards the SW with smoke(FU) and scattered cloudbase at 1500 feet.
Smoke plume over approach RWY 09 specific temperature 22,2 and dewpoint 21,7 degrees celcius

The other reports are the same but with different values, one and two hours earlier.

The 3rd Axis
3rd Aug 2002, 02:33
Thanks for your help dechipering that guys.

It brings me to the question: How many other countries use Imperial measurements, (that is other than the ICAO standard feet for altitude etc), such as statute miles and InHg for pressure.

Is there any talk of aligning all measurements worldwide, including countries using metres to measure altitude? Some sort of standard?

Do pilots having to deal with these changes in units of measurements get confused from time to time.

Thanks

3rd Axis

chiglet
3rd Aug 2002, 09:56
3A,
Here in the Uk we have a mix. [As does most of Europe]:)
Windspeed is in Knots. Vis in Metres/Kilometres. Cloud now Few Scatt, etc in Feet. Alimiter in Millibars [1013Mb = 29.92In Hg :D
Hope this helps
we aim to please, it keeps the cleaners happy

Tinstaafl
3rd Aug 2002, 11:10
Fuel measurement is the biggest pain in the @rse.

Could be bought in L or US Gal, weighed in lbs or Kg, consumed in Kg, L, US Gal or Imp. gal.

Next is horizontal measurement.

Navigate in Nm (usually), vis. measured in Km or m. , runways in m or ft. Except USA where it's navigate in Nm or Sm, vis in Sm & fractions, runways in ft.

Scallywag
3rd Aug 2002, 11:13
3A, the "Jeppesen Supplement" or "Aerad", or whatever your company uses has all the differences from ICAO standard for each country. For example, some countries in Europe use wind speed in metres/sec instead of knots, and cloudbase in metres instead of feet.

bookworm
4th Aug 2002, 10:05
Fokker-Jock gave an excellent decode, with one little exception:

SLP200 is a sea-level pressure of 1020.0 hPa.

If the sea-level pressure were 20 hPa greater than the altimeter setting, it would have to be rather chilly at an airport with an elevation of 81 ft. :)

The FMH (http://205.156.54.206/oso/oso1/oso12/fmh1.htm) is useful for decoding US reports.

Fokker-Jock
4th Aug 2002, 13:49
I stand corrected. You are absolutely right.