Help with weather charts

[Tesaje]

Originally Posted by norm

The best way to measure how dry the air is is by dew point which measures the amount of moisture in the air. Humidity measures the moisture as compared to the temperature whereas the dew point is a pure measure irregardless of the temperature. A good site for this is: http://www.ask.com/web?q=climate+in+...city+ut&qsrc=8
this site gives you all weather data by month plus the annual averages.

True, altho technically the dew point measures the saturation point of the air. The lower the dew point, the less water vapor in the air.

The city-data charts are remiss in labeling them just humidity and not relative humidity. It's just that - relative.

Unfortunately, the link does not identify the period of record or source of the data. Reporting stations do monthly reports like that every month so the climate averages could be quite different.

[Artful-Thang]

Average temperature/weather data always seems misleading to me. Not just here, but any site that compiles info.

The city I live in gets in the 90s in July and August and sometimes we have to run our air conditioner at night because it doesn't cool down enough, yet the average temperature data and charts always look much nicer.
http://www.city-data.com/city/Rancho...alifornia.html
If the weather was really like the chart, I'd be pretty happy.

I used to think maybe because the charts are averaging not only the daytime and nighttime temps, but also all info ever collected. This shaves off the higher and lower temps.

Then when I started poking around the National Weather Service and related web sites, I found no weather station close enough to Rancho Santa Margarita to be a true indicator of our temps. I think the closest one is a several cities over, an area which gets more coastal breezes and is therefore more moderate. If official weather stations are always located at airports, then the weather info for my city is totally off, since our county's airport is near the ocean.

So I don't really trust any weather charts for cities anymore, UNLESS it states exactly where the info comes from.

I like to look at the official data for weather extremes, knowing where the station is located, and the time period that the info used was collected for. Then I figure that chances are pretty good that the weather will stay within those extremes.