WASHINGTON, June 16 (Reuters) - Southwest Airlines (LUV.N) canceled nearly 300 flights Wednesday and delayed more than 500 a day after it was forced to temporarily halt operations over a computer glitch. The Federal Aviation Administration said Tuesday it had issued a temporary nationwide groundstop at the request of Southwest Airlines to resolve a computer reservation issue. "While our technology issues from Tuesday have been resolved, we are still experiencing a small number of cancellations and delays across our network as we continue working to resume normal operations," airline spokesman Dan Landson said. Tuesday"s groundstop lasted about 45 minutes, and ended at 2:30 p.m. EDT Tuesday (1830 GMT), the FAA said. FlightAware.com, a flight tracking website said Southwest had canceled 315 flights Wednesday through 2 p.m. EDT, or 8% of those scheduled, and delayed a further 562. Southwest said it had canceled about 500 flights Tuesday and delayed hundreds of others after the stoppage, which it said was the result of "intermittent performance issues with our network connectivity." Southwest delayed nearly 1,300 flights on Tuesday, or 37% of its flights. Earlier Southwest reported a separate issue that required a groundstop Monday after its "third-party weather data provider experienced intermittent performance issues ... preventing transmission of weather information that is required to safely operate our aircraft." The airline said that issue affected several hundred flights and was resolved after 11 p.m. CDT Monday.