UNDERSTANDING NWS FORECAST TERMS

2/3/2016 (Permalink)

(Courtesy: National Weather Service/NOAA, Department of Commerce)

Since we do 24 hour emergency water damage cleanup we definitely keep an eye on the weather.  Each time it rains or storms we can get a wide range of phone calls from overflowing sump pumps to leaky windows & roofs, so it's important for us to follow and understand Weather Forecast Terminology.  Here's some helpful information that should help you understand what all those weather terms mean.

Understanding the terminology behind weather forecasts is an integral part of our everyday decision-making. Below are common weather terms and their meanings.

Sky Condition

Sky condition describes the predominant/average sky condition based upon the amount of sky covered by opaque (not transparent) clouds.

Sky Condition                                                 Percent of Cloud Cover

Sunny or Clear                                              0 to 5%

Sunny or Mostly Clear                                    6 to 25%

Mostly Sunny or Partly Cloudy                        26 to 50%

Partly Sunny or Mostly Cloudy                        51 to 69%

Mostly Cloudy or Considerable Cloudiness        70 to 87%

Cloudy or Overcast                                        88 to 100%

Wind

Wind describes the prevailing direction from which the wind is blowing with speed in miles per hour. The numbers may vary in other parts of the country due to variation in terrain and elevation.

Sustained Wind Speed              Descriptive

0 – 5 mph                               Light, light and variable or calm

5 – 20 mph                             None used

15 – 25 mph                           Breezy 

20 – 30 mph                           Windy

30 – 40 mph                           Very windy

40 – 73 mph                           Strong, dangerous high winds

74 mph or greater                   Hurricane force

Temperature

Forecast temperature describes the forecast maximum and minimum temperatures or in some cases, the temperature expected at a specific time. Temperature is reported in degrees Fahrenheit.

Description Examples                      Range

Near 40                                         Approaching 40 or a                                                             range from 38 to 42

Around 85                                     Range of temps                                                                     from 83 to 87

Lower 50s                                     Temperatures                                                                       of 50 through 53

Middle 70s                                     Temperatures                                                                       of 74 through 76

Upper 30s                                      Temperatures                                                                        of 37 through 39

60s                                                Temperatures                                                                        of 60 through 69

Probability of Precipitation (PoP)

Probability of Precipitation (PoP) is the likelihood of measurable precipitation (or water equivalent of frozen) precipitation falling during a specified period in the forecast area. Measurable precipitation is equal to or greater than 0.01 inch (0.2 mm) over a period of 12 hours, unless specified otherwise.

At times, NWS forecasters may use “occasional” or “periods of” to describe a precipitation event that has a high probability of occurrence, i.e., they expect any given location in a forecast area to most likely have precipitation, but it will be of an “on and off” nature.

PoP                               Percent Expression of Uncertainty                 

20%                              Slight chance                                                 

30 – 50 %                      Chance                                                          

60 – 70%                       Likely                                                                

80 – 100%                     Rain/Snow, etc.                                             

Information shared from the NWS website.

SERVPRO of Upper Darby, PA & SERVPRO of Bear/New Castle, DE, proudly serves those in need!  We will be on site quickly and our staff will give you the personalized attention you deserve.  We specialize in the cleanup of water damage, fire damage, smoke damage, mold removal, trauma cleanup, vandalism cleanup, carpet cleaning and duct cleaning.  Let us help you make it, “Like it never even happened!”  Visit either of our websites for assistance.  Pennsylvania customers visit –www.SERVPROupperdarby.com or www.SERVPRObearnewcastle.com if you’re located in Delaware.  To speak to a qualified team member, call 1-877-352-0700.