Narrative:

On star [arrival] for [runway] xxr RNAV approach; red storm cells between zzzzz and ZZZZZ1. While descending on VNAV path cleared by ATC to deviate; [we were] below 4;000 feet [and] got pull up red warning on captain terrain display and pull up audio. First officer had weather radar on his side; he executed escape maneuver. At 5;000 feet and heading 140 with approach; flew to initial approach fix ZZZZZ2 to complete RNAV xxr approach. Normal landing. [We] did not stay on STAR and RNAV course line and deviated around weather in area of terrain. [I suggest to] fly a course deviation away from runway and approach course to the northeast and then south away from weather to the south initial approach fix; where no weather was depicted. Also; ask ATC if another aircraft had flown through storm cells painted on weather radar and if ride report available. Communication was difficult; the controller not always reporting back a clearance confirmation or question on weather; so [it was] safer to go the long route rather than depend on controller for help.

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Original NASA ASRS Text

Title: 737-800 Captain reported a Terrain Warning and executing the Escape Maneuver after maneuvering for weather without assistance from ATC.

Narrative: On star [arrival] for [Runway] XXR RNAV Approach; red storm cells between ZZZZZ and ZZZZZ1. While descending on VNAV PATH cleared by ATC to deviate; [we were] below 4;000 feet [and] got PULL UP red warning on Captain terrain display and PULL UP audio. First Officer had weather radar on his side; he executed Escape Maneuver. At 5;000 feet and HDG 140 with approach; flew to Initial Approach Fix ZZZZZ2 to complete RNAV XXR approach. Normal landing. [We] did not stay on STAR and RNAV course line and deviated around weather in area of terrain. [I suggest to] fly a course deviation away from runway and approach course to the northeast and then south away from weather to the south Initial Approach Fix; where no weather was depicted. Also; ask ATC if another aircraft had flown through storm cells painted on Weather radar and if ride report available. Communication was difficult; the controller not always reporting back a clearance confirmation or question on weather; so [it was] safer to go the long route rather than depend on controller for help.

Data retrieved from NASA's ASRS site 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.