By Noel Randewich, John McCrank and Alun John

SAN FRANCISCO/NEW YORK/LONDON, Sept 29 (Reuters) - In the weeks before heading to San Francisco for their vacation this month, Jeff Skipper and his wife Valerie, from the United Kingdom, watched helplessly as the U.S. dollar continued its meteoric rise against the British pound.

The sterling/dollar exchange rate – which slumped to a record low this week – has reduced the affordability of the already pricey Golden Gate City for the couple, forcing them to economize on some holiday luxuries.

"The exchange rate has been the biggest topic of conversation since we got here," said Jeff Skipper, 50, an electrician.

"Everything is pretty expensive for us," said Valerie, a 47-year old university administrator.

"We've been buying food from grocery stores rather than having sit-down meals because when you change it to the British amount, it doesn't seem worth it. It's really a lot of money."

The pair are among droves of visitors to the United States feeling the pinch of the mighty greenback, which scaled two-decade highs this month driven partly by Federal Reserve interest rate hikes.

For British tourists in the United States, the pain of the rampant dollar has been amplified by the collapse of the pound, which entered a near free fall on Monday after the British government announced unfunded tax cuts that sent investors fleeing.

Sterling hit a record low of $1.0327 on Monday, having plummeted 20% against the dollar this year. It was trading just above that on Wednesday at $1.0888.

"Now it's one dollar to the pound…It's really hit us," said Colin Taylor, a retired telecoms engineer from the United Kingdom who was also visiting San Francisco with his wife.

"We have breakfast and it's cost us 50 quid, 50 pounds, you know. And if this were at home it would be 20 or 25 pounds. So it's a big, big jump for us."

'TOO HIGH'

While the pound has experienced some of the most violent gyrations in recent days, currency markets across the board have seen huge swings amid increased geopolitical tensions and central bank rate hikes to tame soaring inflation.

The relative strength of the U.S. economy has allowed the Fed to raise rates more aggressively than its peers, however, pushing the dollar up against the British pound, the euro and Japanese yen, as well as a slew of smaller currencies.

The dollar index, which measures the greenback against a currency basket, hit a fresh 20-year high of 114.78 on Wednesday.

"The dollar is too high. So we are spending, but not the way we would like,” said Jose Alvado, a 48-year old public accountant from Argentina who was visiting New York with his wife and two daughters.