B737-800 rejects takeoff due to apparently anomalous windshear alert warning.

Attributes
ACN	773642
Time
Date	200802
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mia.airport
State Reference	FL
Altitude	agl single value : 0
Aircraft 1
Controlling Facilities	tracon : svmi.tracon
Operator	common carrier : air carrier
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	773642
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	aircraft equipment other aircraft equipment : pws(protective wind shear wng sys)
Resolutory Action	flight crew : rejected takeoff
Supplementary
Problem Areas	Environmental Factor Flight Crew Human Performance Aircraft
Primary Problem	Ambiguous

Narrative:

VFR conditions at takeoff; wind 150 degrees; 11 KTS; runway 8R. 'Windshear ahead; windshear ahead' warning at about 60 KTS. Takeoff was discontinued. Cleared runway; tested system; checked normal. Numerous takeoffs by other airplanes without incident. WX was benign. Normal takeoff with no further incident.

Original NASA ASRS Text

Title: B737-800 REJECTS TKOF DUE TO APPARENTLY ANOMALOUS WINDSHEAR ALERT WARNING.

Narrative: VFR CONDITIONS AT TKOF; WIND 150 DEGS; 11 KTS; RWY 8R. 'WINDSHEAR AHEAD; WINDSHEAR AHEAD' WARNING AT ABOUT 60 KTS. TKOF WAS DISCONTINUED. CLRED RWY; TESTED SYS; CHKED NORMAL. NUMEROUS TKOFS BY OTHER AIRPLANES WITHOUT INCIDENT. WX WAS BENIGN. NORMAL TKOF WITH NO FURTHER INCIDENT.

Data retrieved from NASA's ASRS site as of May 2009 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.