Rain Category

·         With very few exceptions, this category consists of all rain events for the entire 6 hour period.

o        95%  of the total events were all rain

o        5%    of the total events rain mixed with trace frozen or freezing rain

o        75 total events

 

Principal forecast issues

·         Significant cold air advection near the beginning of the 6 hour period may TREND the precipitation types to a rain/trace frozen mix toward the end of the 6 hour period.

·         Surface wet bulb temperatures should always be used in conjunction with partial thickness to ensure that there is no shallow near ground sub-freezing layer present capable of producing freezing rain.

 

Vertical temperature profiles associated with rain

 

Tentative findings

 

Footnote