Sunday, April 28, 2013

Tomorrow's Shower Threat

The approach of showers to our west today means that tomorrow will be a damp day around the region as these showers push on through.  Expect showers to overspread the region from southwest to northeast through the course of the day, with the city getting in on the showers probably in the late morning and the Shore getting them shortly thereafter.

Showers could yield periods of steady rain at times but this does not look like a particularly heavy rainfall overall.  Modeling indicates the prospect of a quarter to half inch of rain throughout the Delaware Valley, with the NAM a bit more robust with rainfall than the GFS, but that general quarter to half average holds serve for Monday PM and Monday night.

These showers ware in association with a disturbance that will track to our south but be slow to depart, held up by a generally slow moving pattern in the Atlantic thanks to a large storm that's cut off near the Azores Islands.  This means the road upstream from the stall is backed up with meteorological traffic. The result is a slow-moving pattern for everything in general...which means that tomorrow's system will be slow to clear out of the region.  We *could* see it clear in enough time Tuesday afternoon to allow for some sun before sunset Tuesday evening but odds favor a mainly cloudy regime into Tuesday with showers lurking around in the morning hours.

This meteorological roadblock out in the Atlantic will help gum up the works later in the week as a storm system fires up in the Plains.  Modeling has waffled a bit in how this storm system evolves but has generally shown a cutoff scenario developing somewhere in the eastern half of the country.  More recent modeling has keep the cutoff farther to our west and keeps the rain chances away from us until late in the weekend.  Give the fickleness of cutoff lows, next weekend's forecast has relatively low confidence from our current perch.