[su_note note_color=”#ffffff”]Updated Sun 09:09 AM —Cloud forecast has changed.   Low clouds now should thin out later this morning.  Sun though high clouds by noon.  Becoming cloudy again mid afternoon. High 72.3º Some models have light showers moving in early evening. [/su_note]

Yesterday’s forecast for Sunday remains intact, based on the tonight’s short range models just becoming available. For several weeks now, I’ve been using the latest,  pre-release versions of the HRRR and RAP models, scheduled to become operational on May 26th.

Sunday Forecast—

  • Sun through high cirrus clouds in the morning.
  • Increasingly cloudy from west to east after noontime.
  • Areas in NJ may be slow to cloud over.
  • Breaks of sun may briefly return late afternoon.
  • High temp  NBM 71.1º sd 2.6º (high spread)   HRRR 70.3º
  • Winds E—> SE light in the morning, then 10-15 mph

There’s increasing uncertainty about the forecast for Monday through Thursday.  The coastal tropical system may become absorbed by the low pressure system in the Midwest.  The models are having issues resolving where the heaviest rain will fall; some keep the rain substantially away from Philadelphia.

It’s a complex setup which is part of a blocking pattern, a closed upper low/surface low in the Midwest and a semi-tropical low off the SE coast.   Will have to see how it plays out.