It is not beyond the realms of possibility that Thomas Hale went to work in the coalmines in Warwickshire or some other (perhaps related industry), lived and worked there for a while and then moved back with his wife before emigrating to the USA. Nuneaton was at the centre of the West Midlands' coal industry but also famous for other major industries e.g. cloth/textiles. As far as mining is concerned, people moved from one pit to another, particularly in the period to which you are referring. One of the biggest eye openers for me when doing family history research has been how much people moved around.
Members of my family worked in the iron industry and moved away from the Forest of Dean to the USA (Poughkeepsie and some of their in-laws went working in Pennsylvania).
Those engaged in mining moved backwards and forwards from The Forest of Dean' to South Wales, the West Midlands and others to other coal fields in e.g. the York, Derby Notts Coalfield, Lancashire, Kent, or even further north to the area around Newcastle, County Durham and to Scotland and vice versa. Coal seams would be opened and when the coal had been removed/the seam had been exhausted the jobs would end and people would then move elsewhere to where new seams were being mined. People might also move to be close to relatives who had settled elsewhere. We are talking about the Victorian Era when people were treated as pawns by those who employed them and when men, women and children were exploited in the pits (though by the time the ancestors you speak of were working things had somewhat improved in terms of child labour law and education reform) people worked in terrible conditions hence the reason for many people emigrating to the USA, Canada, Australia, New Zealand etc.
Warwickshire is not very far from Gloucestershire and with the railways travel between these areas became easier.
The person he married could have been from the Forest of Dean or from Warwickshire or her family could have moved there from somewhere else. Also bear in mind that women in those days were also put into service with rich families and this could mean moving away from the place where the person grew up or being moved if the family she worked for moved house or had houses in more than one area (e.g. the landed gentry usually had more than one stately home in the British Isles).
It is worth comparing place of birth in more than one census record to make sure that there is not a transcription error or rogue piece of information. Not finding someone's birth record in an area does not conclusively mean they were not born there.
Check dates of birth and places where the rest of the family were born. The name Townsend is not uncommon and it could be the same person or someone different, I have found several people in my family history research where there are two or more possibilities and it's best to keep an open mind, to look at both, compare them until more is discovered. You will be surprised when you find the right one, or, if this one is confirmed as the same person as it usually leads to finding more family members as a result. Hope this makes sense.
Another thing to consider is whether Edith was her only name, why I say this is that my father's great Auntie lived in Canada. He and one of his other aunties always referred to her as "Aunt Alice"but I have found that her relatives in Canada referred to her by her first name and that Alice was her middle name! Once I had established this it all slotted into place!
There are Hales in my family tree too from the Forest of Dean, related through marriage, also involved in mining but they seem to have stayed put.

There are three Edith Townsends listed in the parish records on this website, one is Edith Townsend daughter of John and Mary born 1857 in English Bicknor. Does she fit the bill?

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THOMAS HALE Pedigree
Male Family

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Event(s):
Birth:
Christening:
Death:
Burial:

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Parents:
Father: HENRY HALE Family

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Marriages:
Spouse: EDITH TOWNSEND Family
Marriage: 02 NOV 1878 Stockingford, Warwick, England

Husband Age at Marriage: 23
Wife Age at Marriage: 22

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Messages:
Extracted marriage record for locality listed in the record. The source records are usually arranged chronologically by the marriage date.

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Source Information:
Batch No.: Dates: Source Call No.: Type: Printout Call No.: Type:

M042712 1876 - 1895 1067549 Film NONE


Sheet: 00

Hello
Many thanks for your help in solving my query.
Paul's find in the IGI of the marriage parish for Thomas Hale and Edith Townsend was a breakthrough. The actual place of marriage on that entry (Stockingford) rather than the registration district which I had found previously (Nuneaton) made sense when I took Rookancestry's suggestion of looking wider in the family. The name Stockingford rang a bell so I dug a bit deeper in my notes and found the marriage of Thomas's brother Milson Hale (1858 – 1927) to Elizabeth Proctor in Stockingford a few years before the marriage of Thomas and Edith. So it looks like Thomas went to Nuneaton to work in the coal mines there along with his brother Milson. That makes it most likely that I have the correct Thomas Hale and that his wife was indeed Edith Townsend.
Thomas and Edith moved around a lot, presumably because of work. So far I have found them in the Forest of Dean, Yorkshire, Nottinghamshire, the USA and now Warwickshire.
Edith died in Roslyn in the state of Washington on 6 December 1900, aged 41. By sheer coincidence a friend has bought a house there. She has sent me a photo of Edith's grave and of the coal miners' memorial there which has the name of another Hale on it, Mitchel Hale having died there in a pit explosion in 1892. I wonder if any other Forest of Dean miners went out there too. Although Mitchel was not born in the Forest he was the son of another Thomas Hale (1832 – 1883) from Coleford who left to work in Nottinghamshire and Yorkshire.
Roslyn became a bit of a ghost town after the mines closed but it was revived in the 1990s as the setting for the US TV series 'Northern Exposure'.
Thank you once again for your help. I shall add Edith to the list of emigrants on the site now that I know her family name.
Lesley