Gives a rough idea of Dewpt. Most likely close enough though.
I'm wondering if anyone could please give me the formula for the calculation of dewpoint temperature given relative humidity, current temperature, and station pressure
First calculate the saturation vap. pres. es ¶ at temperature T (oC):
es = 610.78 * exp {A T / (T + B) }
where es in Pa, A = 17.2694 and B = 237.3 for T>0 otherwise 265.5.
Then calculate the actual vapour pressure e ¶ using
e = rH / 100 * es
where rH is the rel.hum in %. Finally invert the equation for es since e = es(Td). The dewpoint temperature Td (oC) is then obtained from
Td = B f / { 1 - f }
where
f = ln ( e / 610.78 ) / A
(Based on Monteith and Unsworth, 1990, Principles of Environmental Physics, sec.ed., Arnold, London, 291pp. ISBN 0-7131-2931-X. Note however that their equation 2.25 for Td is wrong) N.J. Bink