ECMWF – European Centre for Meteorology Forecast model.
EL NINO- A major warming of the equatorial waters in the Pacific Ocean. El Nino events usually occur every 3 to 7 years, and are characterized by shifts in “normal” weather patterns.
ENSO – El Nino-Southern Oscillation.
ENTRAINED / ENTRAINMENT– Refers to the drawing in of moisture (or lack of moisture) into a system. Dry air entrainment into the mid levels of a thunderstorm can enhance the potential for damaging wind gusts. Moisture being entrained into a storm system can enhance precipitation amounts.
EQUIVALENT POTENTIAL TEMPERATURE– The temperature of a parcel of air after all moisture and latent heat is condensed out of an air parcel then descended to the 1000 mb level. Also known as Theta-E
ETA– “Eta” (from Greek) model generated every 12 hours by NCEP
EVAPORATION – the process of a liquid changing into a vapor or gas.
EXTENDED OUTLOOK – a basic forecast of general weather conditions three to five days in the future.
EXTRAPOLATE– Determining the value of a meteorological value beyond the bounds of a data sample.