We can say that a language is safe if its words are transmitted from generation to generation and the younger people are able to speak it fluently. In order to see which of the Scandinavian dialects are endangered, we first need to understand what an endangered language is.
List of Endangered Scandinavian dialects

Scandinavian Dialects
A language spoken by children, usually only at home is endangered, but a language that children learn more as their native language is definitely threatened. Seriously endangered is the language spoken by the older generations or parents, but their children neither speak, nor understand the language. Critically endangered is a language that the youngest speakers are grandparents and older, and they speak the language partially and infrequently, while the extinct language is considered language that has no general speakers.
Scandinavia is a Northern European region that covers the three kingdoms of Sweden, Denmark, and Norway. These three countries share strong linguistic, historical, and cultural ties. Most of the national languages of these three countries are mutually intelligible. The Scandinavian dialects belong to the group of languages called North Germanic Languages. Each major language in the Scandinavian region, Danish, Swedish, and Norwegian, has multiple dialects. The more the distance between areas, the more the differences between the dialects of those area will be.
When a language becomes endangered, that means it has only a few speakers left. When that language is not taught to the young generations and the older generations who knew the language pass away, it becomes extinct. Languages become extinct when children have to learn English or any other language for academic reasons, and their parents don’t burden them with the native language. As a result, the native language doesn’t get passed on to the children, and it dies slowly.
Swedish dialects
In the list of Vulnerable Scandinavian dialects is the Scanian dialect (also spoken in Denmark).
Definitely endangered: Dalecarlian dialects, Modern Gutnish, North Saami language (also spoken in: Finland, Norway and Russia) and the Yiddish language (also spoken in: Germany, Belarus, Austria, Belgium, Estonia, Denmark, France, Finland, Hungary, Norway, Romania, Netherlands, Poland, United Kingdom, Russia, Slovakia, Switzerland, Czech Republic and Ukraine).
Severely endangered languages are: Lule Saami (also spoken in Norway) and South Saami language (also spoken in Norway).
And critically endangered are Pite Saami language (also spoken in Norway) and Ume Saami language.
Finnish dialects
In the list of definitely endangered Finnish languages are: Karelian language (also spoken in Russia), North Saami language (also spoken in: Norway, Russia and Sweden), Olonetsian language (also spoken in Russia), Romani language (spoken across Europe), Njukča and Yiddish language (also spoken across Europe).
Severely endangered languages are: Inari Saami and Skolt Saami language (also spoken in Norway and Russia).

Danish dialects
In the list of vulnerable Danish languages are Low Saxon language (also spoken in: Germany, Netherlands, Poland and Russia) and Scanian dialect (also spoken in Sweden)
Definitely endangered: South Jutish (also spoken in Germany) and the Yiddish language.
Norwegian dialects
In the list of definitely endangered Norwegian languages are: North Saami language (also spoken in: Finland, Russia and Sweden).
Severely endangered languages are: Lule Saami language (also spoken in Sweden), Skolt Saami language (also spoken in: Finland and Russia) and South Saami language (also spoken in Sweden)
And critically endangered is Pite Saami language (also spoken in Sweden).
Icelandic
This language is not yet on the list of endangered languages, although more and more people use English instead of Icelandic. Also, the industry has recently decided to no longer add Icelandic menus on some electronics (TV sets, phones).
According to the list above, there are quite a few Scandinavian Dialects which are critically endangered and may disappear during the next 20 years. We’re slowly loosing our roots for the good of progress. Whether that is a good idea or not, remains to be seen in the future.