UPDATE 1-Tower Group Q3 profit tops Street, sees weak Q4

* Q3 EPS before items beats estimates by $0.08 * Net premiums earned rise

* Investment income falls

* Sees Q4 below Street

Nov 6 (Reuters) - Insurance company Tower Group Inc (TWGP.O) posted a third-quarter profit above Wall Street estimates, helped by a 21 percent rise in net premiums earned, but forecast weak fourth-quarter earnings.

The company earned $16.7 million, or 72 cents a share, compared with $14.4 million, or 62 cents a share, a year earlier. Excluding items, it earned 79 cents a share.

Last month, Tower Group said it expects to record a non-cash impairment charge of $2.1 million in the third quarter related to bonds issued by recently bankrupt Lehman Brothers Holdings Inc (LEHMQ.PK), and said it does not hold any other securities issued by the company.

Net premiums earned to $88.2 million, while net investment income fell 15 percent to $8.2 million.

For the fourth quarter, New-York based Tower Group expects to earn 80 cents to 85 cents a share, while analysts were looking for 91 cents a share.

Shares of the company closed at $19.67 Wednesday on Nasdaq. (Reporting by Anurag Kotoky in Bangalore; Editing by Amitha Rajan)