Coastal storm could spoil pleasant weather week

In a post yesterday, we touched on the fact that a few forecast models were honing in on the potential development of a coastal storm later this week. Those models continue to harp on that idea — and others have hopped on the bandwagon over the last 12 hours. The storm looks to develop as a result of a mid level disturbance, which will be shifting eastward amid a generally quiet mid level pattern — as a ridge builds over the Eastern United States. But the disturbance has a mind of its own, and it will shift from the Tennessee Valley to a position off the East Coast on Thursday.

A surface low pressure is expected to develop from Wednesday into Thursday — all forecast models agree on that. The exact track will obviously have big impacts on our forecast. Newer forecast models have continued the trend of strengthening the storm, and tracking the center of low pressure very close to the Mid-Atlantic coast. With a slug of moisture surging northward near the coast, this would mean increasing potential for moderate to heavy rain in our area on Thursday.

Obviously, one of the main concerns with the evolution of the storm system is the center of low pressures track — which will ultimately occur as a result of exact perturbations and nuances aloft.  The high pressure to the north and mid level pattern may act to suppress the storm system. This is becoming less likely over time, as models have continued to trend toward a less suppressive-type pattern. But, if the high pressure trends stronger, the storm will be forced to track southeast of the area sparing us any heavy rain.

NAM model showing very gusty winds near the area beaches on Thursday as a result of the coastal storm.

Should the storm come far enough north and west to impact our area, a windy and rainy day would become likely on Thursday. The strong high pressure to the north and the pressure gradient between it and the developing storm system to our south would create a strong onshore flow — with gusty winds and heavy rain near the coast.

We’ll be keeping a close eye on the potential development over the next day or so. Forecast models are still inconsistent with the storms track and impacts — but stay tuned for updates as we draw closer to the event.