– an accumulation of broken river ice caught in a narrow channel that frequently produces local floods during a spring break-up.

– liquid rain falling and freezing on contact with cold objects creating ice build-ups of 1/4th inch or more that can cause severe damage.

– Wind speed, in knots, of the average PBL windspeed.

– An increase in temperature with height. The reverse of the normal cooling with height in the atmosphere.

– Drawing an isopleth between known numerical values.

– This is a trough which bulges to the north. Mid-latitude troughs have a north to south amplitude but in the tropics the opposite is the case. Inverted trough look like ridges but there is lower pressure at their centers of curvature. Inverted troughs can occur across areas of the tropics and sub-tropics.

– In the Vicinity OF