Limitations of METAR (pressure reading)

infrequentFlyer

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Some METARs give pressure in hPa in the remarks section, but they chop off the thousands and hundreds digits (SLP132 = 1013.2 hPa).

This might be a rare case such as a storm and you probably wouldn't be flying anyways, but if the pressure got low enough wouldn't it be indistinguishable from a high pressure reading?

For example, if the remarks said "SLP500", it could be interpreted as 950.0 or 1050.0 hPa.

The body of the METAR has the pressure in inHg, so this can be used to interpret the remarks. But I'm still curious, is there is any special remark which would distinguish 950 from 1050 hPa?

Thanks in advance
 
A sea level pressure 950 would be reported as 950. Only the 1000s is dropped off.

METAR-slp.png
“It means the Sea Level Pressure is 1008.8 hectopascals. If the value is below 1000 then you will see it written like this: SLP952 or 995.2 hectopascals. If there is no SLP available you will see SLPNO.”

More info here.
 
you will see it written like this: SLP952 or 995.2 hectopascals

if SLP952 = 995.2 hPa then I believe hundreds are chopped here too.

...but I can go cross-eyed looking at all these abbreviations sometimes.
 
950 hPa is 28.00 inches of mercury, which is as low as altimeters go.
1050 hPa is 31.00 inches, which is as high as altimeters go.

if the METAR said SLP500, I think the context would make it obvious which it was.
 
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