Spring Thread 2017: Northern Hemisphere (direction, snow, warm, Chicago)
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
Location: Live:Downtown Phoenix, AZ/Work:Greater Los Angeles, CA
27,590 posts, read 14,728,809 times
Reputation: 9169
Advertisements
Quote:
Originally Posted by Ed's Mountain
Interesting, but 10 measurements may not be enough to confidently estimate the mean.
In order to have confidence in your estimate of the mean you need to know what kind of probability distribution you're dealing with and have some estimate of the variance, e.g. standard deviation. For example if the temperature follows the normal distribution and the standard deviation is 5°C the you need at least 20 measurements to have 95% confidence in your estimate.
Alternatively based on the 10 measurements you've provided the 95% confidence interval for the mean is from 22.3°C to 29.7°C, again assuming a normal distribution.
Of course temperatures in most places do not follow a normal distribution so things are even more messy than that.
Edit: should say 11 measurements. Same logic applies.
I was just showing a rough estimate, because to show all 319 days worth of data I used to get the March 12th number(February 26th thru March 26th every year from 2000-2010) would have been too much data to post here. But the average of all 319 of those numbers rounds up to 78°F, and was showing that even a rough estimate comes close to it.
I explained that I used 29 day averages for each day, which is how NOAA figures averages as well, just for 11 years instead of 30
I was just showing a rough estimate, because to show all 319 days worth of data I used to get the March 12th number(February 26th thru March 26th every year from 2000-2010) would have been too much data to post here. But the average of all 319 of those numbers rounds up to 78°F, and was showing that even a rough estimate comes close to it.
I explained that I used 29 day averages for each day, which is how NOAA figures averages as well, just for 11 years instead of 30
It remained cloudy and the temperature didn't get above 53F (12C) today. The high on Wednesday has been lowered to 52F, and the overnight low to 28F (-2C)!
Athens, GA got 9" of snow on March 24, 1983; 3" of snow on March 13, 1993; and 7" of snow on March 1, 2009. Snow isn't common in the South in March, but it's not as rare as people think either.
You live in the piedmont where it is less rare. There were areas around Wilmington and Myrtle Beach getting hit with snow earlier today. It IS extremely rare for those coastal/lower elevation areas.
Also, I'd keep an eye on Monday night in your area. Says all rain at the moment, but has temps dropping into the 30s.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
