There's a problem with the WU API JSON returning incomplete data for one field 'fcttext_metric' which is 'null'.
It should be the Metric version of the text forecast like:
"forecast":{
"txt_forecast": {
"date":"5:52 AM CET",
"forecastday": [
{
"period":0,
"icon":"chancerain",
"icon_url":"http://icons.wxug.com/i/c/k/chancerain.gif",
"title":"Wednesday",
"fcttext":"Mainly cloudy and windy with occasional light rain...mainly in the morning. High 46F. Winds W at 25 to 35 mph. Chance of rain 40%. Winds could occasionally gust over 40 mph.",
"fcttext_metric":"Mostly cloudy and windy. Periods of light rain this morning. High 8C. Winds W at 30 to 50 km/h. Chance of rain 40%. Winds could occasionally gust over 65 km/h.",
"pop":"40"
}
but instead, it has
"forecast":{
"txt_forecast": {
"date":"5:52 AM CET",
"forecastday": [
{
"period":0,
"icon":"chancerain",
"icon_url":"http://icons.wxug.com/i/c/k/chancerain.gif",
"title":"Wednesday",
"fcttext":"Mainly cloudy and windy with occasional light rain...mainly in the morning. High 46F. Winds W at 25 to 35 mph. Chance of rain 40%. Winds could occasionally gust over 40 mph.",
"fcttext_metric":"",
"pop":"40"
}
and that stops the current WU-forecast from processing a forecast if metric units are used.
I can do a quick-fix that just substitutes the Imperial for the missing Metric forecast, but that can lead to other confusion.
Parsing/fixing the text temperatures / windspeeds in the imperial forecast to metric is a much larger task and may break with non-English forecasts.
I think they have to fix the API (which is not providing data according to their docs). Grrrr.
I see on the
WU API community forum that this problem is 'known' but unresolved as yet. Note that this impacts all metric UOM forecast users.
