Arthur Maintains Strength…Heads NorthJuly 2nd, 2014 at 9:16 am by Jeremy Wheeler under Weather
*See below for the 2pm update.
There’s a lot to cover in this weather blog. Besides Arthur there is also a a chance for thunderstorms today and the heat index will be near 100. I’ll cover Arthur first and then talk a little more about our local weather.
Arthur is currently a tropical storm. Even though it seems to want to form an eye feature on the satellite/radar.
This has been noted by the National Hurricane Center. There is dry air to the north of the system, but it has had little effect on the storm up to this point. The water temperatures are plenty warm in that region. The wind shear is very weak. So the sustained winds have increased to 60mph. It was moving north at 6mph. The pressure had dropped to 996mb, but then it came up to 998mb. The storm is forecast to move northward today as it strengthens. Then it is forecast to start turning northeast by Thursday.
It is also forecast to reach hurricane strength by Thursday. The hurricane will move towards the southern Outer Banks from Thursday night into early Friday morning. It will move rather quickly at about 25mph. I’ve mentioned in past blogs that typically this will weaken a hurricane, but it seems that Arthur will be unique. At least according to the models. By Friday evening the storm will move away from our region. It will be well to our northeast, and the winds will subside. Many folks will probably still be able to go to a fireworks show. A cold front will move into the region at about the same time, and the upper level winds ahead of it should steer Arthur quickly to the northeast.
The models are in fair agreement for the track, but they have yet to close-in on an exact solution. The consensus (grey line) is just a bit offshore from Hatteras.
Notice that there are a couple of models which bring the hurricane just (west) of Hatteras. The GFS Model has it going pretty much right over Hatteras. The European model has the hurricane passing about 50-90 miles to the southeast of Hatteras. As you can see there are a couple of models that swing the storm way offshore. One of them is the Canadian model (yellow line). There is a low confidence in that solution.
So basically there are two scenarios that we are looking at. The first scenario is less likely, but more threatening. If the hurricane passes just west of Hatteras and more inland, then the wind threat will increase.
Then we could see hurricane force winds over the southern Outer Banks and mainland Dare county. At least in the gusts. Tropical storm force winds (39mph or greater) would be able to make it well into Hampton Roads and to the Eastern Shore. Gusts 25-35mph would be possible west of the yellow area. Heavy rain would be able to fall in the yellow and orange area. Moderate to major tidal flooding would be possible around Hatteras with moderate tidal flooding across the Outer Banks and some minor tidal flooding in Hampton Roads and the lower/middle Chesapeake Bay. This is preliminary, but it is the general idea.
If the hurricane were to follow the more likely scenario of just offshore, then the worst conditions would be very localized.
The hurricane force gusts would be confined to the Hatteras area and some of the southern Outer Banks. There is a hurricane watch for Mainland Dare county and the Outer Banks Dare county down to Hatteras. The tropical storm force winds would be confined to the Outer Banks and parts of northeast North Carolina. Possibly up to Virginia Beach. Winds west of the line could get up to 25-30mph. There would will be moderate (maybe major) tidal flooding down towards Hatteras, but it would probably be minor up to Virginia Beach. The Bay might see a little water rise, but not too bad. Heavy rain would be confined to along the coast and mostly northeast North Carolina.
Either way there will be a high threat for rip currents on Friday. Even if the storm moves far offshore, there would be high waves and a high threat for rip currents into the weekend.
So those are the basics of Arthur.
Locally we will have a hot/humid day. Highs will be in the mid 90s. The heat index will be near 100 degrees. We’ll pop-up some scattered showers and storms this afternoon. We already had a couple spots of heavy rain this morning. Tomorrow we’ll see a cold front approach from the west. We’ll have scattered showers and storm out ahead of it. Both today and tomorrow there could be some heavy rain, but storms are more likely tomorrow. The front will move through late Thursday into early Friday. This should help to push Arthur offshore. If the timing of the front changes, then the speed and track of Arthur could also change. The upper level winds (trough) will be the main steering current though.
Folks in Hatteras may have to evacuate. Residents along the southern Outer Banks may have to as well. I would start making preparations down there. I don’t see evacuations elsewhere at this time. We still have some time to refine the exact track.
The National Hurricane Center still has the storm on a similar forecast track. At this point wind speeds are at 60mph sustained with a movement to the north at 7mph.
You can see the Hampton Roads cities is not in the forecast cone, so the strongest parts of the storm will remain out to sea by Friday morning. The OBX is still in the storm’s path. I will be writing another blog following the NHC’s 5pm update, stay tuned.
Meteorologist Jeff Edmondson & Meteorologist: Jeremy Wheeler