* Q4 pretax profit 638 mln DKK vs 554 mln forecast
* Combined ratio 87.4 percent vs 92.2 percent
* Result helped by lower weather claims
* Shares jump 6.1 pct (Adds details, CEO comment, share price)
COPENHAGEN, Feb 7 (Reuters) - Tryg A/S, the Nordic region's second-biggest insurer, posted a larger-than-expected quarterly pretax profit on Thursday, boosted by lower weather-related claims than in 2011.
Pretax profit for the fourth quarter rose to 638 million Danish crowns ($116 million) from 467 million a year before.
The result was above an average forecast for 554 million crowns in a Reuters poll of analysts.
The combined ratio - the percentage of revenue spent on claims and costs - was 87.4 percent, against an average forecast of 92.2 percent. A figure below 100 shows an underwriter is profitable.
The company said the improvement reflected in part the impact of its cost-cutting programme, as well as fewer winter claims than usual.
"It's a combination of our own doing and significant help as well", chief executive Morten Hubbe told Reuters.
Tryg proposed a dividend per share of 26 Danish crowns and a share buy back of 800 million crowns.
Shares in the firm were up 6.1 percent at 0822 GMT against a 1.1 percent rise in the Copenhagen main index.
The company said it expected weather claims net of reinsurance to total 500 million crowns in 2013, and large claims of 450 million crowns.
$1 = 5.5098 Danish crowns Reporting by Johan Ahlander; Editing by Mark Potter