The world is in the middle of what will probably be the hottest of the 10 years since records began in 1850, says the Met Office.
It is predicting that temperatures for each of the next five years will likely be equal to or greater than 1C compared to pre-industrial levels.
There is also a small chance that global temperatures will temporarily exceed 1.5C over the next five years.
This is seen as a critical threshold for climate change.
If the data matches the forecast, the 2014-2023 decade will be the hottest in over 150 years of record keeping.
The Met Office says that 2015 was the first year in which the annual average global surface temperature reached 1C above the pre-industrial level, which generally means temperatures between 1850 and 1900.
We have just made the predictions this year and they are going to go until 2023 and what they suggest is a rapid global warming, "said Professor Adam Scaife, head of long-term prediction for the Met Office, BBC News.
"Looking at individual years in this forecast, we can now see for the first time that there is a risk of a temporary, and, I repeat, temporary overcoming of the extremely important 1.5C level set out in the Paris climate agreement."
Last October, UN scientists published a special report on the long-term impacts of a temperature rise of 1.5 ° C.
They concluded that it would take a major carbon-cutting effort to keep the world from reaching the limit by 2030. The Met Office analysis now says there is a 10 percent chance of that happening in the next five years.
"It's the first time that forecasts show a significant risk of overcoming – it's only temporary. We're talking about individual years floating above the 1.5-degree level," Professor Scaife said.
"But the fact that this can happen now due to a combination of general warming and fluctuations due to events like those of El Niño in the next few years means that we are approaching that threshold."
The Met Office says it has a 90 percent confidence limit on forecasts for years to come.
He says that from 2019 to 2023, we will see temperatures ranging from 1.03C to 1.57C above the level of 1850-1900, with rising warming in much of the globe, especially in areas such as the Arctic.
The research team says it is fairly certain in its predictions because of its past experience. The team's previous forecast, made in 2013, predicted the rapid warming rate seen in the past five years. He even predicted some of the lesser known details, such as the cooling spot observed in the North Atlantic and the colder points in the Southern Ocean.