Category Archives: Weather Outlook

Weather Pattern Change

This post was revised

GFS Surface forecast for Tuesday
GFS Surface forecast for Tuesday

Over the past few weeks, the weather forecasts beyond 3 or 4 days have been anything but reliable. Perhaps you’ve noticed?

With much of the energy coming in from the Pacific ocean where measurements are sparse, the weather system developments over the US have been difficult to pin down.

We are now going to see a major change in the overall weather pattern, perhaps due to the next phase of the Madden-Julian Oscillation. Over the next week, an anomalously large area of high pressure will settle into the Southwest and Rocky mountain states bringing extremely cold temperatures to areas that last winter were very warm.

We will get colder, but the frontal boundary of this cold air will be not too far to our south.

The disturbances hitting the west coast from the Pacific are expected to be shunted to the south below this boundary.

The GFS currently keeps us cold and dry.

Here’s the rub– with this sort of scenario, it doesn’t take much for a disturbance to form along the stalled frontal boundary. So instead of just cold and dry weather (as currently predicted by the GFS) we could end up with icy or snowy storms. Stay tuned.

Phillly Winter Weather Oulook

This post was revised

The current mild pattern will slowly revert back to more average December temperatures over the next several days.

A storm that had been expected to form over the weekend will probably pass off to our south,

The models are advertising a big change around Christmas Eve, with deep amplification of the jet stream, colder temperatures and possibly the development of a major storm. Stay tuned.

Philly Winter Weather Outlook

This post was revised

This weekend, we are entering into a period where the weather models are showing big differences in the forecast from run to run and between different models.

The upcoming weekend looks to be cloudy and wet, particularly on Saturday, but there’s a chance of a coastal storm developing anywhere in the time period from Sunday through early Tuesday.

It appears that it will be too warm here for snow. But while wet is much more likely than white, there’s even uncertainty about how amplified the jet stream may become and how much cold air will be present.

One thing that is becoming clearer….there is a change in pattern from last year’s highly amplified jet and oppressive cold weather, with extreme dry weather in the west.

This pattern reminds me of the last solar cycle peak in 2001 where we had very warm periods in January and February and more rain than snow.

December Weather Outlook

This post was revised

Looking at the medium and long range GFS models– A relatively mild stretch of weather is shaping up for the first half of December. Mild, cloudy and wet seems to capture it.

Maybe my sense of a milder winter may come true despite the cold period we just experienced.