A warm front will move through this evening with cloudiness. Clouds break Saturday morning as the front moves to our north.  A southwesterly flow will bring very mild temperatures and mostly sunny skies by mid day. High temperatures may exceed 60 degrees on Saturday. It will be breezy as well.

Update Sat 1 PM: An upper air disturbance with moisture at 300 mb has caused mid and upper level cloudiness to develop today.  Sometimes referred to as a ‘dirty high pressure system’.  Not sure if we’ll get the sunshine that was expected this afternoon.

For Sunday, a cold front will pass through early morning with some cloudiness and skies will clear by noon. Temperatures will remain mild for most of the day with mostly sunny skies and high temperatures about 56.   Temperatures will become cooler towards evening.

Update Sat PM: A secondary cold front moves through Sunday evening, so mostly cloudy Sunday afternoon.   It looks like we’ll have some showers late Sunday afternoon.

The outlook for next week – an amplified jetstream pattern redevelops over the eastern US  and the models are hinting at some sort of storm development in the Tuesday through Thursday  timeframe. The details of the storm development are unclear at this time, but expect the mid week period to be very active.

No real change in the very cold weather forecast this weekend.

However…

Yesterday, I wrote about the next storm expected to reach our area late Monday into Tuesday. The trend over the past few days has been to move the track westward, putting us on the warm side of the storm, giving us a transition to rain.  In fact, it was expected to get quite warm on Tuesday.

Today’s GFS has moved to a different possibility, with the cold air maintaining its grip longer in our area, allowing a greater chance of snow Monday evening and freezing rain/sleet into Tuesday.  There even was the suggestion that enough cold air would remain to prolong the snow in southeastern PA well into Tuesday.

So, what looked like a likely snow->sleet> freezing rain>heavy rain scenario for late Monday into Tuesday is now not so clear-cut.  There may be a more snow, sleet and freezing rain from this storm in SE Pennsylvania.    Stay tuned.

Fri 10:45pm:  Latest NAM model  indicates snow may start late morning or noon Monday and several inches may accumulate before a changeover to sleet and freezing rain late Monday or Monday night, especially north and west.  New Jersey, south and east, will have a more rapid warmup.. This may be a significant storm, especially north and west of PHL before a changeover to rain.

The timing and track of this storm continues to change.  While an eventual transition to all rain still is most likely, the models often predict the lower atmosphere to warm up faster than actually occurs.

The deep dip in the jet stream today will be reinforced with another shot of cold air on Saturday.

The polar front moves through before daybreak Saturday morning, the winds pick up and temperatures stay steady during the day.  Mostly sunny, some clouds.  High 19.

Due to the winds, Saturday may feel like the coldest day of the weekend, but in terms of temperature, the cold air will be entrenched Sunday, and high temperatures may just hit 15!   Less windy on Sunday with partly sunny skies.

Storm outlook:

A storm approaches from the south late Monday.  Light snow late Monday afternoon, will change  to sleet and freezing rain, then rain likely by Tuesday morning.   Quite mild by Tuesday, with heavy rain expected.   Possibly a brief snow shower late Tuesday night as temperatures drop again.   An upper air disturbance may bring a period of light snow on Wednesday.