Tuesday September 11th, 2018
Chief Meteorologist Chris White
Good Evening. I apologize for running late but here are our updated high impact weather graphics. Florence has went though another eyewall replacement cycle and the new eye is slightly smaller at about 10 miles in diameter. Florence though continues to grow and expand. She is still a very dangerous category 4 hurricane moving NNW.
The high pressure ridge continues to build and strengthen to the North and out over the Northern Atlantic. The ridge has built south in behind Florence and in response Florence is almost moving at 20mph. High pressure continues to move South from the Great Lakes into the Ohio Valley. Models all are pointing at Florence running into that block from those high pressure ridges and halting forward progress around hour 72, which is Friday. At that point look for Florence to stall along the East Coast. Florence arrives as a high end category 3 or low end category 4 hurricane with catastrophic damage expected around the area it comes on shore. We have highlighted that Florence could weaken slightly before landfall in previous discussions and The National Hurricane Center indicates that models could be picking up on Florence’s own outflow, so questions rise about that.
Currently Florence is expected to make landfall between Wilmington and Morehead City. It is however very important to note that the cone of uncertainty extends down to Charleston. Where Florence stalls is a huge key factor in what will happen from there. If it stalls just offshore it will be able to maintain more of its strength but if it stalls over land it should spin down fairly quickly.
FOOTHILLS WEATHER NETWORK AREA:
Major model guidance indicate Florence moving West after that stall along the Coast. While the winds don’t appear that they will be a huge factor for our area some gusts 20-30mph are possible. Rainfall will be our biggest concern. Right now it looks like a decent place to start at with 3-6 inches through most of the coverage area. We indicate some higher totals on the eastern slopes but it is important to note here that those are highly dependent on the track of Florence. I Florence were to say track North through North Carolina and pass to the east then we would need to bring these 4-8 inch totals down along the Blue Ridge because upslope flow would not be a huge factor. If Florence were to take a track just to the SW of our area then that puts us on the right side of the disturbance and easterly flow will pile up the precipitation over that highlighted 4-8 inch zone. So with everything here it is very important that you monitor later forecasts and the adjustments that may need to be made.
We have been getting alot of questions about evacuations. Emergency Management normally does not evacuate inland areas ahead of the storm because there really is no need for it. If you live in a flood prone area it would be great for you to start making plans of where you can go if flood warnings are issued for your area.
Landslides and mudslides are of great concern with this impactful tropical cyclone. The mountains and foothills have been very wet overall this year and are already above normal on rainfall for the year in most cases. The amount of rain that moves in with Florence would likely cause a lot more of the hillsides to collapse. This is something that cant be forecast but if you live in unstable areas it would be good for you to have an emergency plan as well because you could have to leave at a moments notice.
Tornado threat will be low overall in our viewing area we think right now. Of course the right region of a tropical cyclone is more apt to create tornadoes than any other side. The good thing here is that Florence will likely weaken substantully before coming inland so for now we will keep our coverage area in a low risk for tornadoes.
Wind Damage should also be minimal across our viewing area. Florence is expected to weaken rapidly once it makes landfall. The most wind damage will likely be to trees and powerlines because of saturated ground.
ALL OF THIS SHOULD BE MONITORED FOR CHANGES AND UPDATED FORECASTS.