Crossing the dateline under sail and weather
PLEASE can someone fix this. We are at sea and are moving from French Polynesia to Tonga. Tonga is on the other side of the time zone vs French Polynesia. We had planned weather based on front arriving on a specific day using time zone for French Polynesia. However once you change your time zone to Tonga you suddenly loose a day and weather shows up differently since now front shows on the “day” as per Tonga time zone. No place does it show this “day” being lost on the timeline. We are now faced with a frontal system hitting us with 30 knot headwinds. Please can we get this fixed.
Crossing the antimeridian (dateline) results in the change of date. From a West longitude to an East longitude, the date is increased by one day (Saturday to Sunday).
In Windy the map shows days and times of your own location.
But, if you use the weather picker to get a local forecast, the days and times are those at the picker location as shown here (in the mobile app):
So, when you are planning a long passage with Windy, the weather events are shown at your local time (local time of your computer).
But of course when sailing these weather events will take place at different local time when you will change time zones. At sea, change of one hour per 15° longitude... and one day at 180° longitude.
Did you use the Route planner to plan your passage ?
Thank you Idefix. Yes agree you see picker for specific location, but when looking at an area which crosses zones like this would be useful for it to label exactly which time zone it is using to show. Perhaps it does but i cannot see it.
Route Planner does not seem functional on ipad. It will let me put in a route but what shows up ito of wind direction the arrows seem to be off by 180 from convention used elsewhere in Windy. So I abandoned..
The wind is from the E / ESE which is where the arrows are point. WInd is shown elsewhere as where it is going.
would be useful for it to label exactly which time zone it is using to show. Perhaps it does but i cannot see it.
No, time zones are not clearly shown in Windy. But at sea and for pilots, it should be a very useful addon in the map items list such as Reported weather stations, Airports, Windsurf spots… You can only rely on the change per each 15° of longitude and at 180° meridian. Showing UTC time also helps:
So, it is important to show the lat, lon grid as displayed in your screenshot. Unfortunately this grid is not really visible with some layer colours. It should be thicker or with possibility to turn it black or gray.
Route Planner does not seem functional on ipad.
It works well, but the default wind direction reference is set to Left to right. See explanation:
In the mean time, a change has been made in last version v39.2.1 and we have now the possibility to set the direction reference to North up.
When crossing the date line the Route planner does not works properly and does not show the change of date. Or you have to plot it in 2 sections (east and west side of dateline)