UPDATE 3-Lotos sees weaker Q4 after Q3 beats forecasts

* Q3 net profit 579.4 mln zlotys vs yr-ago 237.9 mln loss

* Beats market forecasts for 386 mln zloty profit

* Shares rise 1.6 percent

(Adds quotes, forecasts, updates share price)

By Patryk Wasilewski and Pawel Bernat

WARSAW, Nov 5 (Reuters) - Poland's No. 2 refiner Lotos LTOS.WA says earnings are likely to drop back in the fourth quarter after a better-than-expected swing back to profit in the previous quarter.

The third-quarter net profit was helped by gains on foreign currency-denominated loans and higher oil prices that boosted inventory values.

However, Chief Finance Officer Mariusz Machajewski expects the positive effect of the stronger zloty to dissipate in the fourth quarter, while operating profit will be hit by usual seasonal factors.

"On the net level we will see totally different numbers, as there will be no debt adjustment. Operationally it might be slightly weaker as the third quarter is the best season and the macro conditions do not improve," Machajewski said.