Special Weather Discussion

Latest Weather Discussion by Kyle Elliott

* significant "january thaw" this week *

1:30 p.m. Tuesday, January 6, 2026:

The first 5 days of 2026 were brisk and unseasonably cold across the mid-Atlantic States, but there has been nothing to show for it in terms of snowfall following the early-morning squall on New Year's Day. Moreover, winter will essentially take a hiatus through the upcoming weekend, and zonal (west-to-east) flow will flood the nation with mild, Pacific air through the rest of the week. In fact, a deep trough, or dip in the Jet Stream, will swing through the Western States over the next 48 hours and then eject into the Plains from Friday into Saturday. Ahead of it, the Jet Stream will bulge northward over the Eastern States, and temperatures will, therefore, end up significantly above normal from Wednesday-Sunday. After our prolonged stretch of frigid and blustery conditions since the beginning of December, this "January Thaw" will be most welcome. In addition, bouts of much-needed rain will accompany it from Friday through Saturday night and *perhaps* put a slight dent in the drought conditions across the region.

A warm front lifted northeastward through the Commonwealth yesterday, and southerly flow behind it ushered more seasonable air into northern MD and southeastern PA. The southeasterly flow has continued to push milder air into the region today, and temperatures have reached the low-to-mid 40s early this afternoon despite mostly cloudy skies. A relatively weak and fast-moving storm system will zip through southern New England tonight. Its track will be too far north for any substantial precipitation south of Interstate 80, but a few showers may still graze the Lower Susquehanna Valley between 4 PM and Midnight. However, there will be little if any impact from the rain, and amounts should not exceed 0.10" in any location. In fact, many areas may not even receive measurable rain, and those south of the Mason-Dixon Line will probably just stay dry (see below). Due to the clouds and isolated showers, temperatures will remain above freezing tonight and only bottom out in the mid-to-upper 30s. 

Behind the system, west-northwesterly winds of 10-20 mph with gusts up to 30 mph will usher drier air into the region on Wednesday. As a result, skies should at least be partly sunny, and that sunshine will boost high temperatures into the upper 40s along I-81 to mid 50s in the I-95 corridor.. some 10-15°F above average (see below). An area of high pressure will then settle into the mid-Atlantic States from Wednesday night into Thursday and cause winds to subside. In addition, it will promote mostly sunny, calm and pleasant conditions on Thursday with highs around 50°F (see below). Needless to say, Thursday will certainly be the nicest day of the entire week, and I highly recommend taking advantage of the beautiful weather. The sunshine is going to feel great! We have reached the end of the frozen tunnel.. at least for now.. 

Looking ahead toward the end of the week and upcoming weekend, there are currently BIG differences between the numerical computer models regarding the timing, progression, strength and evolution of a pair of storm systems slated to track from the southern Plains into the Great Lakes region and southeastern Canada. Thus, I won't take a shot at predicting rainfall amounts from Friday-Sunday or timing the cold frontal passage just yet. Having seen these situations before in my career, my intuition tells me that the front will sweep through the Commonwealth from Saturday night into Sunday morning with the "wettest periods" being Friday evening and later Saturday afternoon into Saturday night. However, that's just a "best guess" at this point. Regardless of the eventual outcome, clouds will increase, lower and thicken Thursday night, and you'll need to keep an umbrella handy from Friday afternoon through Sunday morning (see below). Fortunately, the mid-Atlantic States will be deep within the systems' warm sectors, so there won't be any concern for wintry precipitation. In fact, high temperatures should soar into the 50s on Friday with lows in the 40s Friday night. Highs on Saturday will then depend on the exact timing of the second system and surface wind direction ahead of it. If winds remain southerly, then temperatures might pop into the low 60s for a few hours Saturday evening. Then again, they may hover in the 40s if a sneaky, backdoor cold front pushes south of the Mason-Dixon Line Friday night. Either way, it's going to be an abnormally mild 5 days, and there may even be ice jams on the Susquehanna River over the weekend.

Not until later Sunday morning or afternoon will howling, northwesterly winds return and usher chillier and more seasonable air back into the Eastern States. The air mass behind the front doesn't look particularly "cold," but Sunday will likely be a "falling temperatures" type of day with highs then in the upper 30s to perhaps low 40s on Monday. Factor in sustained winds of 15-30 mph with gusts up to 45 mph, and it will certainly feel much colder in comparison to this week. I'll finesse the details of the forecast over the weekend on Friday morning, so check back then for an update! -- Elliott