High Wind Warning: -- Issued when wind speeds of sustained 40 mph with gusts to 58 mph are occurring or imminent.
High Wind Watch: -- Issued when potential exists for wind speeds of sustained 40 mph with gusts to 58 mph, but timing and location of storm are not certain.
Wind Advisory: -- Sustained winds of 30-39 mph or gusts of 45-57 mph are expected or occurring.
Flood Watch: -- This means flooding is possible within 48 hours. These are issued by county and cover all rivers inside the county in question.
Flood Warning: -- These are issued by individual river and mean flooding is imminent or occurring.
Urban and Small Stream Flood Advisory: -- Localized flooding from heavy rain in city or rural areas. Typically non-life threatening.
Heavy Snow Warning: -- For the mountains above 2,000 feet, this is 12" of snow or more in 12 hours, or 18"+ in 24 hours. For the lowlands, it's 4" or more in 12 hours or 6" or more in 18 hours.
Winter Storm Warning: -- Conditions for Heavy Snow Warning plus added element of wind or other hazard.
Winter Storm Watch: -- Warning-like conditions possible with the next 12-48 hours.
Snow Advisory: -- For the mountains, it's 6-11" in 12 hours or 11-17" in 24 hours. For the lowlands, it's 1-3" in 12 hours or 3-5 inches in 24 hours. (Sometimes this also comes out as a "Winter Weather Advisory" -- that might mean it could be sleet or freezing rain too)
Severe Thunderstorm Warning: -- Thunderstorm with 58 mph winds and/or large hail are occurring or imminent.
Tornado Warning: -- Tornado spotted on the ground or indicated by radar.
(Severe Thunderstorm and Tornado Watches have never been issued here)
Sometimes a "Significant Weather Advisory" is issued for strong thunderstorms that don't quite meet the criteria of a "severe thunderstorm" but warrant attention nonetheless.
You can read more at the National Weather Service site