I hope that you enjoyed your small dry spell, because those days have now passed and the deluge of rainfall will continue around WNC. Most models indicated that around 5” of rainfall or even more will fall across the majority WNC by the end of the day on Friday, with some isolated locations seeing 10”+ of rain. Below you can see the most recent European model precipitation forecast and what how much precipitation it is projecting through Friday afternoon.

Track Storms Moving Into Your Area On The Official AshevilleWX Live Radar

Yes, that is just one model.. but it has been showing this amount of precipitation constantly for the past several runs, and now the GFS model has began showing similar total. If you joined me live last night, that was the one caveat in my forecast as to why I was apprehensive to call for extremely significant rainfall for all of WNC. As you can see below the GFS is now indicating that those 2”+ totals will even be possible down towards locations like Franklin & Murphy, NC. So with that being said, flash flooding will be likely all across WNC.

Flash Flooding, Mudslides Likely Along Blue Ridge Escarpment

These significantly high rainfall total will cause several problems around WNC including mudslides. Slopes around the area will struggle to handle round after round of heavy deluges and eventually isolated slopes will give way. Of course it is uncertain where exactly those slope failures will occur, but with this amount of rainfall projected, it appear imminent that it will occur. Streams & rivers will also rise quickly across WNC when heavy rainfall moves in periodically over the next 5 days, and if water begins to threaten your home you need to move to higher ground. Ponding on the roadways is all but certain over the next 5 days so please use caution if you are out and about traveling around WNC, roadways could turn dangerous. Below you can see what the short range Nam 3km projects regarding precipitation through mid day on Wednesday. The areas I am most concerned about are located along the Blue Ridge Escarpment. If you reside in the circled locations, please know that your location is at a higher risk for significant rainfall and flooding.

Timing

Well if you look out your window, most of you will find that it is already raining or has rained at your home in WNC… and that looks to be the theme through Friday. Showers & storms will be periodic over the next several days, and nailing down exactly when it will and won’t rain at your house will be a matter of evaluating the radar in real time. You can find the official AshevilleWX Radar here. Below you can see a depiction of how the situation could possible unfold per the Nam 3km. This is just a simulated radar, but will give you an idea of the round after round idea of rainfall that I am expecting.

What Is Causing This Prolonged Rainfall?

A strong Upper Level Low pressure will move over the mountains of WNC and basically stall out as it pushes Tropical Storm Arthur out to sea. This strong cold pool of air aloft will create excessive lift and massive amounts of precipitation will be squeezed out of a saturated airmass. Below you can watch the upper air maps and notice how that low just spins over WNC for several days. These spokes of vorticity will spin up storm after storm for the area, with 7”+ of rainfall likely falling somewhere by Friday.

Mild Pattern Setting Up

Temperatures on Wednesday morning will feel chilly as the Upper Level Low allows them to drop into the upper 40’s around WNC. This pattern will take hold over the next 10 days, and high temperatures will struggle to reach 80 each day. This is unseasonably cold for this time of the year, and could put this May in the top 10 coolest on record for our area. That remains to be seen though. What I do know currently is that we have to push through these next 5 days of nasty rainfall, but there is some light at the end of the tunnel. Check back soon for more information!

Watch Rain Fall Live On The WNC Webcams