Will Harvey impact us? Yes. But nothing to worry about.
Tropical Depression Harvey is slowly making his way through toward the Tennessee and Ohio Valleys on the way to our area, however, the upper level flow is also going to push Harvey increasingly to the east over time.
Harvey still has a huge pocket of Tropical Moisture with him. This will surge into the southern half of the state. Then the fun begins, from a forecast point of view. What I mean is this: The storm will fizzle and die out. The circulation will cease. This is good from the standpoint of focused heavy rain. But an upper level trough will capture the energy, and help develop a new low to the east of the mountains, in NC/VA. This new low will then move NE and deepen. An increasingly expansive and heavy rain shield will develop along with this new low-pressure area.
This new low is NOT a tropical low, it is a more typical or extra-tropical low-pressure area. This means that it is likely that the models are too far E/SE with the storm and resulting rain. Latest example was Tue. I measured .25” of rain, not a lot that’s for sure, but a whole lot more than most models had. In fact only the RGEM and NAM showed this kind of possibility. And their “solutions” were thrown out by most forecasters. Thus I kept hearing scattered showers possible. It was one long scattered shower we had. It was light, but it was steady.
So, I feel that the models are once again making the same kind of mistake. I expect a soaking rain of around 1” with locally higher amounts from the remnants of Harvey.
Sunday, it clears and turns milder, then Mon and Tue look very nice and mild. Wed we start seeing some changes as a new impressively strong tough develops over the central/eastern US. This trough will bring us some showers Wed, then steadier rain Thu/Fri followed by some rather chilly air, although the coldest of the air will remain to our west.
The tropics are one of concern for us beyond the next 7 days.
- Area of disturbed weather, could become a tropical low of some kind next week, and could become involved in this large trough by the end of last week. This could then enhance our rains substantially late next week.
- Tropical Storm Irma. She is way out in the Atlantic and will not be a threat to the US until after Sept 10. So, we have plenty of time to track her. All indications are that this storm will be large and strong. The atmospheric set-up from what we generally think it will be, is one that favors an east coast threat particularly Fla to NC. This does not mean it will hit, as it could stay off shore and curve away from land as well as stay of Fla and enter the Gulf of Mexico. We do not know, but the pattern suggests that SE US is a historically at higher risk in this kind of pattern.
Friday: Sun and clouds. Refreshingly cool with a breeze.
Saturday: Fading sunshine. Cool with showers developing. Rain overnight.
Sunday: Clearing skies. Milder.
Monday: Mostly sunny. Beautiful. Warm.
Tuesday: Mostly sunny. Beautiful. Warm.
Wednesday: Increasing clouds. Chance for showers or a thunderstorm.
Thursday: Mostly cloudy. Cooler. Chance for rain.