Thursday, February 21, 2008

About These Forecasts

Forecasts produced by The WeatherMan will be posted to this site 5-6 days per week (hey, even God took one day a week off...aren't I entitled to one too?) They will generally be posted by about 5 A.M. and will cover a period from the upcoming night out through the next 5 or 6 days. There will usually be no updates or extra posts except perhaps in cases of extreme weather or a radical change in the forecast, and there is no guarantee of this. In times of severe or life-threatening weather, The WeatherMan recommends obtaining the latest up-to-the minute alerts, warnings and other information from your local TV or radio stations or from NOAA Weather Radio. Posts may be missing due to illness, technical difficulties or other circumstances over which The WeatherMan has little or no control.

These forecasts are produced using information which is freely available on the internet or from other sources. There is no charge for these forecasts and there is no advertising on this site.

FORECAST AREA: The forecasts are targeted mainly to State College and the surrounding townships, also know as the "Centre Region" along with Bellefonte. They are not intended for the western part of Centre Country such as Bald Eagle Valley, the Mountaintop or Philipsburg areas, nor for the extreme eastern parts of Centre County such as Madisoburg, Millheim or Coburn. However if I expect large and important differences in the weather across these areas, I will try to include them in the forecast.

TEMPERATURE RANGES: I use temperature ranges for two reasons. One is that given the difference in elevation and urban versus farmland and forest settings across the region, there will naturally be a few degrees of temperature difference across the area on a given day. Under perfect nighttime conditions, clear sky and light wind, the difference can be huge. The other reason is that thermometers are like scales. Two thermometers placed side-by-side may read two different temperatures. Just like you weigh one thing on the scale at home and something else (usually more) at the doctor's office. The most accurate thermometer is one that is placed in constant shade, a few feet off the ground and not near pavement or buildings.

SNOWFALL RANGES: These are used for pretty much the same reason as the temperature ranges. Rarely is the snowfall exactly the same all across the forecast area, and even if it is, different people will usually measure different amounts. Getting an accurate snow measurement is more difficult than getting an accurate temperature measurement. You should start with a clear and clean cold (preferably frozen) surface so that none of the snow melts. If there is wind or any melting before you measure the snow, the amount may be inaccurate. Even if there isn't, the snow may comact and settle before you measure it also resulting in an inaccurate measurement.

PROBABILITY: I usually don't use probability for a couple of reasons. First of all many people don't understand what it really means. Does a 70 percent chance of rain mean that it will rain 70 percent of the time? NO!! In 70 percent of the area? NO!!! It means that there is 7 in 10 chance that measurable rain (0.01 of an inch) will fall at the forecast verification site. This is based on statistics from previous similar weather events. The other thing is, when it comes down to it, there are only two probabilities, 100 and 0; it either rains (or snows) or it doesn't. All other numbers in between are ultimately meaningless. So I stay away from probability most of the time. I either just predict the precipitation if I think it is pretty likely or definite or I use the words chance/possible or slight
chance if I am less certain.

LEGALESE: The WeatherMan assumes no responsibility for personal, financial or any other type of loss resulting from the use or misuse of any information on this site or from any of the information contained herein being incorrect.

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