heatindex vantage pro2

[ammar]

I want to ask why the heatindex on the vantage pro2 console is different from the heatindex in cumulus it is displayed same as the temperature while all other variable are the same as the console.

[steve]

I don't know, sorry. But if you give me more (or some!) information, I might be able to help. What values are being shown for temperature, relative humidity, and heat index in Cumulus and on the console? What version of firmware does your console have? What version and build number of Cumulus are you using?

Cumulus uses this formula to calculate Heat Index: http://www.hpc.ncep.noaa.gov/heat_index ... ation.html

The Davis console uses a look-up table which is based on the above formula, but with approximations to save space. They have also extended the values below the 80F cutoff which is applied by the formula which Cumulus uses.

[ammar]

on console
temperature=22
relative humidity=88
heat index=23

on cumulus
temperature=22
relative humidity=88
heat index=22

davis vontage pro 2 with weatherlink ip 6555

[steve]

The Heat Index formula only applies when the temperature is above 80F/27C - http://wiki.sandaysoft.com/a/FAQ#My_hea ... emperature

[ammar]

thanks a lot

there is another question please

the davis console displays rounded wind speed km/h ex: 2 km/hr while on cumulus it displays 1.6km/hr
when i ticked round wind speed in cumulus wind is rounded on screen but on weather underground the wind is still displaying decimal values.

and I want to know what is the interval of wind speed. is it 1.6 because it is displaying 1.6 ,3.2,4.8 and so on

[steve]

the davis console displays rounded wind speed km/h ex: 2 km/hr while on cumulus it displays 1.6km/hr
when i ticked round wind speed in cumulus wind is rounded on screen but on weather underground the wind is still displaying decimal values.

Weather Underground requires wind speeds to be upload in mph, and they convert to km/h. The way they choose to display the data is nothing to do with Cumulus.

and I want to know what is the interval of wind speed. is it 1.6 because it is displaying 1.6 ,3.2,4.8 and so on

The resolution is 1 mph (hence 1.6 km/h)

[ammar]

ok so i should change cumulus to mph instead of km/h?

[steve]

ok so i should change cumulus to mph instead of km/h?

You can use whatever units you want. Note that if you do change units, all of your existing data will be invalid, because data is logged in the units you currently have selected.