Monday, August 05, 2013

Showery Regime Returns Tuesday

After a couple of absolutely epic days around the Delaware Valley (yesterday and today), the pattern will gradually transition towards wetter, warmer, and more humid for much of the balance of the work week.

This transition begins tomorrow as a disturbance pushes east along a warm front that will push northeast.  Modeling is showing showers breaking out across the region late tonight, with the consensus of modeling showing these showers pushing through a large chunk of the region tomorrow. The NAM holds some of the shower activity back across western sections to a greater extent than the GFS or Euro, which spread those showers into the city. However, the bulk of tomorrow's shower activity (at least the steadier stuff) should stay west of the Delaware River.

Tuesday's disturbance is the first of three disturbances of sorts that push east through the region over the course of the week. Round two looks to move through in the Wednesday and Wednesday night timeframe, with a third round timed for Friday.  Both of those rounds could produce some heavy rains with the thunderstorm activity that moves through as the atmosphere will be more unstable, have more humidity in it, and both disturbances are a bit more robust than what moves through tomorrow.  Wednesday PM's system, as modeled on the Euro, could produce quite a lot of rainfall in some parts of the region and it would not surprise us if some spots pick up quite a bit of rain from it.

We could be looking at some more localized flooding in spots, depending on how the Wednesday PM storms and the Friday storms materialize for a track. We'll keep an eye on this and update you over the coming days since the detail part of the forecast is a bit sketchy and more of a short-term forecast type setup where the details are pinned down a day or less out. Just know that there are a couple of heavy rain threats later in the week.

Our best chance at 90 comes on Saturday as the frontal boundary slides through during the course of the day and we get a westerly downslope for a time. If the front moves through early enough in the morning, we have a decent enough shot at making that 90 degree run.  That shot is a one-day chance as the trough that reinforces across the East will bring a gradual step down in temperatures for early next week (lower half of 80's for highs possible by Monday). Saturday's shot at 90 requires a perfect set of everything breaking right but it may ultimately be the warm day in what will be a progressively soggy and stormy time of things around here.