-15.4 degrees Celsius = 4.28°F (exact). Rounded: 4.28°F. In Kelvin: 257.75 K. In Rankine: 463.95°R.
Below freezing (0°C = 32°F). Water is solid ice at this temperature.
Below freezing: -15.4°C = 4.28°F. Key landmarks: 0°C = 32°F (freezing), −10°C = 14°F (cold winter), −20°C = −4°F (severe cold), −40°C = −40°F (where scales meet).
All temperature units: 4.28°F · 257.75 K (Kelvin) · 463.95°R (Rankine). Kelvin starts at absolute zero (−273.15°C). Rankine is used in some US engineering applications.
Formula: °F = (°C × 9/5) + 32. For -15.4°C: (-15.4 × 1.8) + 32 = -27.72 + 32 = 4.28°F. Reverse: °C = (°F − 32) × 5/9 = (4.28 − 32) × 0.5556 = -15.4°C.
-15.4°C = 4.28°F (exact: 4.28°F). Formula: (-15.4 × 9/5) + 32 = 4.28°F.
Multiply by 1.8 then add 32: -15.4 × 1.8 = -27.72, + 32 = 4.28°F. Quick estimate: double the Celsius value and add 30 → -0.8°F (approximate).
Add 273.15: -15.4 + 273.15 = 257.75 K. Kelvin is used in science — 0 K is absolute zero (the coldest possible temperature).
Below freezing (0°C = 32°F). Water is solid ice at this temperature. In Fahrenheit: 4.28°F is below freezing.