How will excessive amounts of rain this year affect Fall color around WNC?

Will Fall Color Be A Fail In WNC This Year?

Each year, hundreds of thousands of leaf lookers coverage on the mountains of Western North Carolina in search of fall color at its finest.  Seasoned leaf lookers know that in early October one can begin to see peak color above 5000' in elevation in many locations.  As October progresses, the color seeps down into lower elevations, and then eventually to the valley floor by late October/early November.  This process occurs as Chlorophyll transportation is cut off between the leaf and the tree.  

 

The Color Changing Process

Leaves change color simply due to the reduction of Chlorophyll.  This reduction is the product of shorter days, and longer nights.  With less light available during the day, the leaf is no longer able to make the amount of energy necessary for survival.  As the nights lengthen and cool down approaching fall, a cork-like barrier develops between the stem of the leaf, and the tree.  The tree does this in order to seal itself of from the cold that will ensue during the winter months.  With no flow of nutrients now from the tree to the leaf, Chlorophyll production is eliminated, and the leaf begins to die.  With no Chlorophyll present, the leafs sugars begin to show, giving off the vibrant hues of orange & yellow that WNC is so famous for.  The chart below illustrates this in a bit more detail.

 

Will Excess Amounts Of Rainfall In WNC Affect Fall Color?

The short answer is yes, it will.  Unfortunately, abundant rainfall is not part of the recipe for vibrant fall color in WNC, simply because it prolongs the process.  Chlorophyll is supplied to the leaf a few days longer compared to normal, and the cork barrier struggles to form.  Typically during late October and early November we will have a strong line of storms move through WNC.  Winds gusting over 40mph blow off these leaves that have just begun the color changing process, and we never get to see them fully change.  With WNC well above average regarding rainfall, I expect the color changing process to be slow this year.  I could see chances improve for vibrant color if we were to experience drought conditions over the next month and a half.. but long range models do not believe that that will be the case.  My prediction for leaf season around WNC is that we will see bold colors that take a while to disappear, instead of vibrant colors that only last for a couple of days.  This doesn't mean this fall will be ugly in WNC, because it never is!  There are just meteorological factors that are working against vibrant sugars from being able to manifest themselves.  Spotty fall color will be around though, it will just be more of a challenge to find it! 

14718683_353202938357672_2750696711655227372_n.jpg
Average peak fall color dates by elevation. Use this map to pick higher elevation locations to visit when color has not changed yet in the valleys below.

Average peak fall color dates by elevation. Use this map to pick higher elevation locations to visit when color has not changed yet in the valleys below.

Author: Meteorologist Hunter Ward