Nikkei flat, insurer stocks skid on Harvey impact worries

* Japanese property & casualty insurer shares fall

* Dollar weakens after Jackson Hole speeches sap sentiment

TOKYO, Aug 28 (Reuters) - Japanese stocks ended flat in thin trade on Monday, as investors assessed the impact of a weaker dollar following the Jackson hole central bank conference and casualty insurers fell on worries about the impact of Tropical Storm Harvey.

The Nikkei share average .N225 was flat at 19,449.90, after logging its sixth straight weekly fall on Friday for its longest losing streak since January 2014.

The broader Topix .TOPX rose 0.2 percent to 1,600.12, but turnover was only 1.74 trillion yen. A level below 2 trillion yen is considered thin.

A stronger yen weighed on stock market sentiment. The greenback was down 0.2 percent at 109.15 yen JPY= . FRX/

The dollar came under pressure after Federal Reserve Chair Janet Yellen made no reference to U.S. monetary policy in her speech at the Fed's annual conference in Jackson Hole, Wyoming, while the euro surged after European Central Bank President Mario Draghi refrained from mentioning the euro's recent strength. were sold, with Toyota Motor Corp 7203.T dropping 0.5 percent and Honda Motor Co 7267.T shedding 0.3 percent.

"Investors are waiting for more catalysts, and they will likely refrain from taking large positions until important economic indications come out this week," said Chihiro Ohta, general manager of investment research at SMBC Nikko Securities.

Meanwhile, shares of Japan's property & casualty insurers fell as investors fretted about the impact of the storm hit Houston on Sunday because the insurers may be exposed to losses through reinsurance arrangements with other companies. direct cost of the storm's impact is still unknown, and the global web of the industry's reinsurance ties means that some of the fallout might eventually be borne by insurers far from the scene.

Tokio Marine Holdings 8766.T was down 0.9 percent and MS&AD Insurance Group Holdings 8725.T dropped 0.5 percent.

Shares of H.I.S. Co 9603.T surged 9.5 percent after the Japanese travel agency on Friday posted a jump in its recurring profit in the nine months through July 31.