It's probably wrong to call them 'specialised' ships, John; they were basically ordinary (chartered) merchant ships with two meteorologists* on board to look after the weather observing. That said the British did not again employ ships in the role until 25 May 1944 when two frigates, HMS Hoste and HMS Grindall were deployed to patrol two areas 20-25W 52-59N (Hoste) and 20-25W 43-49N (Grindall). When these were withdrawn towards the end of June another ship was stationed at approximately 50N 20W; in December a second ship was stationed at about 58N 20W - in both instances the ships were constantly on the move over quite a large area.

*There were three meteorologists on board the two ships when they were sunk, the extra men were on their first voyages.

The Americans gradually developed their own network of eight ships between 35 and 55W, 35 and 65N. They were much more restricted in their patrol areas, but none was ever deliberately targeted by U-boats. However, U-755 did torpedo the USS Muskeget on 9 September 1942 near 51.27N 43.45W - not realising what the ship was.

From March 1941 the RAF began flying once daily meteorological reconnaissance sorties from bases the UK and later, Iceland and Gibraltar, to about 700 miles from the base airfields - but that's another story.

PM me your email address and I'll send the article.

Brian