TODAY: Mostly sunny. A possible gust north and west of the Lehigh Valley. High: 45
TONIGHT: Partly cloudy and cold. Low: 25
FRIDAY: A little sun fading behind growing, colder clouds. High: 38, Low: 24
Thanks to the cold front that followed during the night of Tuesday until early morning on Wednesday, a more seasonal mass of air returned to the region. Over the next few days it will continue to cool as a large channel with the jet stream continues to move southeast from Canada and installation shop across the Mid and Northeast Atlantic.
Meanwhile, most of us had mostly clear skies last night, thanks to the dry air that tries to cross from the southwest thanks to the high pressure centered in our southwest. With light winds, temperatures could fall again in the range of 20 degrees Celsius for many places.
Look for a good amount of sun while we work until Thursday thanks to a high-pressure nose that continues to influence the region, centered southwest of us, but extends northeast across the region.
With a breeze from the west blowing cold air through the Great Lakes not yet frozen, the lake effect snow machine will be in full swing. Although we do not normally see much of this activity, some gusts can still be held together in areas north and west of the Lehigh Valley. The high temperatures on Thursday afternoon should again be quite seasonal, generally between 40 and 40 years. It will not be so windy compared to Wednesday.
Clear, partly cloudy skies are expected tonight with calm winds, so once again temperatures should be able to drop to 20 degrees in many places. The high pressure will keep us dry until Friday with a lot of sun to start, but rising clouds later in the day.
It should be colder on Friday as the depression in the jet stream continues to dig southeast in the region. This helps bring cold air reinforcement injections. They will expect high temperatures for many of us on Friday trapped in the 30s.
Friday night through Saturday, the cold front that receded on Tuesday night until early Wednesday will settle on the east coast. At the same time, a low pressure area will be developed on the southeastern coast along the stagnant frontal boundary and will be directed northeastward along it.
Moisture will accumulate along the front and the low pressure system will move northward; to push towards the coast and move inland. The latest trends with computer models, however, continue to suggest that this low pressure system and the stagnant front will be far enough offshore that so much of the moisture has little or no impact on our area.
But areas to the south and east of the I-95 corridor, especially to the coast, you can get a small mix of rain and snow during the night from Friday to Saturday. At this time, this feature continues to look a little more to the southeast to impact most of the area, which must remain cold and mostly dry until the beginning of next weekend. It is still worth looking in case, especially for the place southeast of the Delaware Valley. High temperatures once again on Saturday will probably be back in the 30s for many again.
On Saturday night until Sunday morning, a low pressure system will move through the Great Lakes and continue north of the area. It is quite weak and is hungry for humidity, but some rains or gusts of snow can not be ruled out completely on Saturday night until Sunday morning. This Clipper low pressure system will bring with it a boost of Arctic cold air reinforcement, so look for Sunday's highs to stay in the 30s with a little northwest breeze, which adds additional cooling in the air. Apart from the morning gusts or the snowfall, look for a mixture of sun and clouds on Sunday.
The third and last chance for some snowflakes arrives later on Monday night to Tuesday when another clipper low pressure system from the Great Lakes northeast. This could spread some light rain and snow along its path, although it is still unclear as to the route that this feature will take, and if a coastal redevelopment can occur to improve the rain and snow a bit.
So there is a chance of some rain and snow during the first part of next week's forecast to account for this possibility, although at this time it still seems that there are no major storms in sight. In spite of everything, the cold pattern continues advancing during the next week as the firings of cold arctic air increase behind the aforementioned clipper system. That large channel in the jet stream will remain blocked in the east, and continues to look like a series of low-pressure clipper systems that will crawl through it bringing cold-air booster shots to the region. This means that our weather pattern has temperatures below normal until mid-December.