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rich_g85
20th Oct 2010, 14:41
Hi all,
I am in Boston, USA this week and have booked an hour's aerobatic pleasure flight this coming Saturday at Bedford/Hanscom field.

I was looking at the latest METAR for KBED this morning and I understand most of it but had a couple of questions.

KBED 201356Z 00000KT 10SM CLR 10/06 A2992 RMK AO2 SLP145 T01000061

Presumably 10SM relates to the visibility, ie 10 statute miles?
What is 'CLR'? Sky clear?
What do the remarks mean? I notice Logan Intl have something similar: RMK AO2 SLP135 T01110061

Thanks in advance.

SkyHawk-N
20th Oct 2010, 15:02
10SM - 10 statute miles or more visibility
CLR - Clear skies
A02 - Automatic station with precipitation discriminator
SLP145 - Sea level pressure
T01000061 - Temp/dew-point in tenths °C

Jan Olieslagers
20th Oct 2010, 15:05
Sorry, no reply, only another question: do they really give temperature and dewpoint in degrees Celsius in the USA? I always understood Fahrenheit was still very much alive, there?

172driver
20th Oct 2010, 15:08
1) correct - vis is expressed in statute miles in the US
2) also correct - clear
3) SLP stands for Sea Level Pressure
4) the group starting with A denotes the type of automatic reporting station
5) the group stating with T is the hourly temp/dewpoint

For more detailed info see here (http://atmo.tamu.edu/class/METAR/quick-metar.html)

HTH

172driver
20th Oct 2010, 15:10
do they really give temperature and dewpoint in degrees Celsius in the USA

Yes


and I now have to add a few words to keep the PPrune system happy - and wait for 20 seconds more.....

Jan Olieslagers
20th Oct 2010, 15:53
3) SLP stands for Sea Level Pressure
Many thanks for the quick and concise replies. Unfortunately, you are rewarded by one more question:
if SLP stands for Sea Level Pressure, how to read the 145 (or whatever) that follows? Neither inches of mercury nor hectopascals aka millibars?

flyingpony
20th Oct 2010, 16:05
I believe its hPa to one decimal place, 1014.5

172driver
20th Oct 2010, 16:19
if SLP stands for Sea Level Pressure, how to read the 145 (or whatever) that follows?

Jan, have a look at the link in my first reply - all shall be revealed ;) !!

AdamFrisch
20th Oct 2010, 16:30
Metars have this information at the end so that meteorologists can create weather charts from them. They have little significance to pilots if you just want to make a go, no go decision.

SNS3Guppy
21st Oct 2010, 00:49
When using the metar, the remarks are generally ignored. The meat and potatoes of what you need are found in the body of the metar; winds, visibility, ceiling/cloud cover, temp/dewpoint and altimeter. Bottom line is whether the weather is good or not.

Pick two or three airports in the same general area and sample them to see if any big discrepancies exist and to look at alternate weather, then set them aside. By the time you read them, they're outdated. By the time you take off, they're history. By the time you're arriving, they're ancient history. The METAR is simply a snapshot in time, and shouldn't be relied upon too heavily for determining your plan of action. Especially not the remarks section.