Narrative:

The flight encountered delays into jfk due to thunderstorm activity near the station. I recommended to the crew to divert to their alternate of ZZZ. At approximately the same time ZZZ contacted ATC and advised that they would not accept diversions at ZZZ. Since thunderstorm activity was impacting other potential alternates within the flight fuel range making ZZZ, the only viable alternate, I declared an emergency with ATC and directed the flight once again to proceed to ZZZ. I then called the watch supervisor in ZNY, idented myself as the dispatcher for flight X and advised him that I was declaring an emergency. I told him that I was out of options for a diversion airport. He replied that I should have the pilot declare an emergency. The flight proceeded to ZZZ and landed without further incident.

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Original NASA ASRS Text

Title: AN ACFT DISPATCHER DECLARES AN EMER SO THAT HIS ACFT COULD CONTINUE INTO ZZZ BECAUSE ALL OTHER ALTERNATE ARPT WX WAS GOING DOWN.

Narrative: THE FLT ENCOUNTERED DELAYS INTO JFK DUE TO TSTM ACTIVITY NEAR THE STATION. I RECOMMENDED TO THE CREW TO DIVERT TO THEIR ALTERNATE OF ZZZ. AT APPROX THE SAME TIME ZZZ CONTACTED ATC AND ADVISED THAT THEY WOULD NOT ACCEPT DIVERSIONS AT ZZZ. SINCE TSTM ACTIVITY WAS IMPACTING OTHER POTENTIAL ALTERNATES WITHIN THE FLT FUEL RANGE MAKING ZZZ, THE ONLY VIABLE ALTERNATE, I DECLARED AN EMER WITH ATC AND DIRECTED THE FLT ONCE AGAIN TO PROCEED TO ZZZ. I THEN CALLED THE WATCH SUPVR IN ZNY, IDENTED MYSELF AS THE DISPATCHER FOR FLT X AND ADVISED HIM THAT I WAS DECLARING AN EMER. I TOLD HIM THAT I WAS OUT OF OPTIONS FOR A DIVERSION ARPT. HE REPLIED THAT I SHOULD HAVE THE PLT DECLARE AN EMER. THE FLT PROCEEDED TO ZZZ AND LANDED WITHOUT FURTHER INCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.