Be a wee bit careful with some of the calories burnt tools as they often massively over-estimate. There's a calculation you can use to get a decent figure.
To work out energy expenditure in joules, you multiply average power (/1000) by time in seconds. Thus, the work done in 1-hr at 190 W avg is 684 kj (0.19 x 3600). To convert this to kcal you divide by 4.18, i.e., 164 kcal.
However, the human body when cycling is only around 25% efficient (normal range ~ 20 - 26%), thus, this needs to be calculated, to work out the human energy consumption, i.e., 164 / 0.25 = 656 kcal.
To give you an idea, 190 watts on a flat road would equate to around 26km/hr, so 24km/hr is going to be around the 650 calories mark. Still a decent amount, but I'd take the figure given by many tools with a big pinch of salt.
AS you say, be much nicer when the sun comes out. Did you watch Milan - San Remo on Sunday? Looked pretty epic. Cavendish didn't look very happy after riding for 7 hours in snow and rain!