The basic meteorological requirement for a balloon
flight is calm winds of 15 knots / 17mph or less, good visibility and stable atmosphere
with no thermals, rain or thunder activity. Personally I think over 9 knots / 10mph is a bit fast and will involve a long drag on landing.
These conditions are most
frequently be found early in the morning and the last few hours of daylight in the evening, which is when
most balloon flights take place.
Ballooning is an all year round sport - in the
summer months the long hours of daylight and generally better weather favour
more flying; during the winter months the opportunities for flying tends to be only during working hours so for private balloonists they can only fly on weekends unless they take a holiday.
You do need to register but essential for a ballooning forecast
Pictorial view of UK Metar data
Flight Briefing For Pilots
Weather Web Aviation weather services
Icelandic weather site
Very good site that the forecasters use. Text wind data, select "windgram" and your lat/long position
Paramotoring Site - Link to EGHI
Sun Rise & Sun Set Calculator
Check the NOTAMS
Whatever the weather you should also check the notices to Airmen, best you know if there is a royal flight barrelling straight towards you or the Red Arrows are about to do a display exactly where you want to be.
You need to register but contains all the latest NOTAM information you need for flight planning.
Up to date NOTAMS plotted on a map, or delivered via RSS feeds and Email, you can even plot a course and get all relevant NOTAMS.