Narrative:

During climb out while deviating for weather; WX weak displayed on both captain and first officer HSI screens which soon changed to WX fail. Because of night conditions with scattered to broken thunderstorms enroute; we declared an emergency and returned to [departure airport]. Normal landing weight.

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Original NASA ASRS Text

Title: B757-200 crewmember reported WX radar failed during climb out. Since thunderstorms were forecast enroute the flight declared an emergency and returned to departure airport.

Narrative: During climb out while deviating for weather; WX WEAK displayed on both Captain and First Officer HSI screens which soon changed to WX FAIL. Because of night conditions with scattered to broken thunderstorms enroute; we declared an emergency and returned to [departure airport]. Normal landing weight.

Data retrieved from NASA's ASRS site as of July 2013 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.