RF Cafe Software

RF Cascade Workbook 2005 - RF Cafe
RF Cascade Workbook

Calculator Workbook
RF Workbench
Smith Chart™ for Visio
Smith Chart™ for Excel
RF & EE Symbols Word
RF Stencils for Visio

About RF Cafe

Kirt Blattenberger - RF Cafe WebmasterCopyright
1996 - 2016
Webmaster:
Kirt Blattenberger,
 BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:
 AirplanesAndRockets.com

Try Using SEARCH
to Find What You Need. 
There are 1,000s of Pages Indexed on RF Cafe !

Electronics World Cover,TOC,and list of posted Popular Electronics articles QST Radio & TV News Radio-Craft Radio-Electronics Short Wave Craft Wireless World About RF Cafe RF Cafe Homepage RF Cafe in Morse Code Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs Twitter LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes AN/MPN-14 Radar 5CCG Notable Quotes App Notes Calculators Education Magazines Software,T-Shirts,Coffee Mugs Articles - submitted by RF Cafe visitors Simulators Technical Writings RF Cafe Archives Test Notes RF Cascade Workbook RF Stencils for Visio Shapes for Word Thank you for visiting RF Cafe!

Windchill Chart - Wind Speed vs. Air Temperature

Frostbite Times

 30 minutes
 10 minutes
 5 minutes
I am more of a cold weather person than a hot weather person. However, cold does tend to slow down the movement of my fingers, so working outside without gloves is very challenging.  This information is derived from NOAA. Here is a heat index chart.

In 2001, NWS implemented an updated Windchill Temperature (WCT) index (see table below).


NOAA provides the following equation for calculating wind chill:

   Wind Chill (°F) = 35.74 + 0.6215T -
                              35.75(V0.16) + 0.4275(V0.16),
            where T = Air Temperature (°F),
                       V = Wind Speed (mph)

Wind
(mph)
Temperature (°F)
  40 35 30 25 20 15 10 5 0 -5 -10 -15 -20 -25 -30 -35 40
5 36 31 25 19 13 7 1 -5 -11 -16 -22 -28 -34 -40 -46 -52 -57
10 34 27 21 15 9 3 -4 -10 -16 -22 -28 -35 -41 -47 -53 -59 -66
15 32 25 19 13 6 0 -7 -13 -19 -26 -32 -39 -45 -51 -58 -64 -71
20 30 24 17 11 4 -2 -9 -15 -22 -29 -35 -42 -48 -55 -61 -68 -74
25 29 23 16 9 3 -4 -11 -17 -24 -31 -37 -44 -51 -58 -64 -71 -78
30 28 22 15 8 1 -5 -12 -19 -26 -33 -39 -46 -53 -60 -67 -73 -80
35 28 21 14 7 0 -7 -14 -21 -27 -34 -41 -48 -55 -62 -69 -76 -82
40 27 20 13 6 -1 -8 -15 -22 -29 -36 -43 -50 -57 -64 -71 -78 -84
45 26 19 12 5 -2 -9 -16 -23 -30 -37 -44 -51 -58 -65 -72 -79 -86
50 26 19 12 4 -3 -10 -17 -24 -31 -38 -45 -52 -60 -67 -73 -81 -88
55 25 18 11 4 -3 -11 -18 -25 -32 -39 -46 -54 -61 -68 -75 -82 -89
60 25 17 10 3 -4 -11 -19 -26 -33 -40 -48 -55 -62 -69 -76 -84 -91

Note: Even NOAA uses both "windchill" and "wind chill" on their website, so
          the two forms appear to be interchangeable.

Clinical trials were conducted at the Defence and Civil Institute of Environmental Medicine in Toronto, Canada, and the trial results were used to improve the accuracy of the new formula and determine frostbite threshold values. Standardization of the WCT Index among the meteorological community provides an accurate and consistent measure to ensure public safety. The new wind chill formula is now being used in Canada and the United States.

Specifically, the new WCT index:
  • Calculates wind speed at an average height of five feet (typical height of an adult human face) based on readings from the national standard height of 33 feet (typical height of an anemometer)
  • Is based on a human face model
  • Incorporates modern heat transfer theory (heat loss from the body to its surroundings, during cold and breezy/windy days)
  • Lowers the calm wind threshold to 3 mph
  • Uses a consistent standard for skin tissue resistance
  • Assumes no impact from the sun (i.e., clear night sky)