Disclaimer. This tool is for informational purposes only and is not a substitute for pilot judgment, a proper preflight inspection, or manufacturer guidance. Temperature estimates are based on modeled weather data which may be delayed, incomplete, or inaccurate. Always verify engine temperature with your aircraft's engine monitor before starting. Never attempt flight with frost, ice, or snow on aircraft surfaces — perform a thorough preflight regardless of what this tool indicates. Consult your engine manufacturer's recommendations for preheat procedures. By using this tool you accept all risk; the authors assume no liability for any outcome resulting from its use.