NICOLE OR NOT, TROPICAL STORM CONDITIONS THURSDAY
The remants of tropical storm Nicole is located just south of Florida. Another area of low pressure is developing along the stalled out frontal boundary near the North Carolina Coast. An upper-level low is located over the Tennessee Valley. All of these features on the playing field will promote a rather stormy time of it for us over the next 24 to 36 hours. Our brief dry spell is rapidly coming to an end as rain is already advecting rapidly northward across Virginia and the Delmarva Peninsula this afternoon in response to diffluent flow aloft in advance of closed upper-level low over TN Valley and developing surface low near the Carolina Coast. An increasingly intense southerly flow, from the surface on up, will pump northward a tremendous amount of deep, tropical moisture into our region over the next 24 to 36 hours, especially the second half of tonight into Thursday. Rain with the initial area of low pressure, currently near the Carolina Coast, will overspread the area from south to north later this evening. Aside from pockets of light rain this evening, the bulk of the rain should hold off until after midnight in the city. This area of low pressure will be near the Virginia/North Carolina border tomorrow morning with Nicole situated off the South Carolina Coast. Precipitable water values increase dramatically late tonight through Thursday into the 2.0 to 2.5 inch range as deeper tropical moisture gets drawn northward. The exact center of tropical storm Nicole will become more difficult to track as it heads northward off the East Coast tomorrow and tomorrow night as it will become elongated and more oval shape in nature and there will be a couple of other areas of low pressure trekking along in the flow -- basically an elongated area of low pressure will be in place along the East Coast. In fact, most of the rain we get will have more to do with the baroclinic low developing to our south and the fact that deep, tropical moisture will be overrunning the stalled out frontal boundary along the East Coast and little to do with the actual entity of Nicole. We are looking at rain much of the time tomorrow as it turns progressively windy -- stronger winds near the coast. As of now, we are expecting 2-4 inches of rain in and around the city by the time Friday morning rolls around, locally higher amounts of 4 or 5 inches not out of the question. However, it appears the best moisture influx and upward motion will try to set up just to our west and we expect the axis of heaviest rain to fall across eastern PA and western NJ where a general 3-6 inches of rain can fall tonight through Thursday night, locally 8 inches. We continue to be concerned about thunderstorms with damaging wind gusts tomorrow. In fact, there would not even have to be thunderstorms to get the damaging gusts. Models are showing 60+ knot winds at 850 mb. The trough axis will lift northeastward across the mid-Atlantic tomorrow night, which should start to deflect some of the deeper moisture and what's left of Nicole off to the east-northeast as the night progresses. This should lead to a tapering off trend from west to east with the rain later tomorrow night with most of the rain over with by Friday morning, although we are still allowing for a few lingering showers to start off Friday in case things end up slower.



Recent Comments