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novicef
19th Oct 2016, 06:08
Hi
I hope there is a meteorologist or a pilot, a lot more knowledgeable than I am.
On the chart I have, it has the height in Meters which I understand. However the parts I don't get are where it says
1. WET AREA :: (T-TD less than 3*C)
2. Areas on the chart that show grid lines.
3. Where temps are indicated but in some cases it appears that the Dew Point is higher than the Temp. This I don't understand.
Could somebody please explain this.
Thanks
novice

oggers
19th Oct 2016, 09:33
1. WET AREA :: (T-TD less than 3*C)

The temperature dew point spread is less than 3ºC so the relative humidity is quite high.

2. Areas on the chart that show grid lines.

Not quite sure what you are referring to but lat/long and territorial boundaries are depicted.

3. Where temps are indicated but in some cases it appears that the Dew Point is higher than the Temp. This I don't understand.

Clearly the dew point cannot be higher than the temp. I think what you are looking at is the reported temperature/dew point spread as opposed to the dew point temperature. ie you may see 05 [upper left of symbol] and 6 [lower left], where 05 is the temp and 6 is the spread (not the dew point temp).

underfire
19th Oct 2016, 10:06
Can you post an image of the chart?

Are you talking about a grid like this?

http://i64.tinypic.com/11r6our.jpg

Because relative humidity cannot exceed 100 percent, the dew point can never be higher than the temperature.

RUMBEAR
19th Oct 2016, 10:41
Have you just joined a Japanese airline?