Newman

Once again we failed because 1. Early morning WAA crapvection and 2. Too much forcing for ascent driven by a strong synoptic system, which ultimately leads to clusters of storms every which way simply occupying the same spaces. It's the same problem we had with the Moderate Risk bust a few months ago. Too much convection.

That activity will more likely than not become outflow dominant by the time it reaches the Lehigh Valley. Maybe some embedded spinners, but more likely a damaging straight line wind threat

3000 MLCAPE/5000 SBCAPE creeping into Philly now. Low level lapse rates also finally looking somewhat decent too.

You can find the warm front pretty clearly on the latest 18z SBCAPE mesoanalysis. Surface obs are also evident... middle 80s in York, southern Lanco, Philly right now, but low to middle 70s still across the rest of SE PA. I do think this warm front will continue to lift northward but I don't have much confidence in how much in the next 3-4 hours. Some of that messy cloud debris near Harrisburg appears to be thinning out as it slides eastward, and we're getting more sunshine across the Lehigh Valley... All of that to say I think the Trenton/KOP/Philly area will maximize instability and low-level shear just south of the warm front. We shall see...

Satellite and radar imagery definitely getting that "look" west of Florida with the MCV that is moving offshore. Mid-level rotation quite evident. NHC bumped odds up to 10/30 at 2PM. 12z Euro, GFS, Euro-AI all pinwheel this area of vorticity northward tomorrow up the West Coast of Florida

The trough in the east should quickly pull whatever develops down here northward. Maybe 1-1.5 days over water in the northeastern Gulf

Northeastern Gulf of America: An area of low pressure is expected to form during the weekend over the northeastern Gulf of America. Subsequent slow development of this system is possible while it moves slowly northeastward over the northeastern Gulf and or near the southeastern coast of the United States by early next week. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 7 days...low...20 percent.

..Mid-Atlantic... Farther downstream, scattered to widespread heavy rainfall will be focusing along the wavy, east-west orientated frontal boundary draped over the northern Mid-Atlantic states and offshore south of Long Island. Back building/training of slow moving storms capable of hourly rates rates greater than 2 inches/hour will track across eastern Pennsylvania and New Jersey this evening. Guidance is signaling areal averages of 3 to 6 inches with local maximums of 8+ possible along this corridor. The latest guidance maintains focus of the highest probabilities for the intense rain rates and higher QPF over central to eastern PA, portions of central to northern NJ, and far northern Maryland. The combination of some terrain areas and the highly urbanized corridor makes this area much more vulnerable to flash flooding. While there remains some spatial uncertainty to exactly where the greatest rainfall will occur, the setup favors locally significant flash flooding with the Moderate Risk over eastern Pennsylvania and north/central New Jersey embedded in the Slight Risk that now spans from northeast Indiana and southeast Michigan (including Detroit) through the Mid- Atlantic Coast from NYC to central Virginia.

Allentown gusted to 50 mph with this line moving through, Mount Pocono 54 mph, Lancaster 47 mph, Reading 47 mph

Well the NWS has implemented new policy/guidance that has completely stripped the human input in forecasting for days 4-7. And even days 1-3 are heavily produced based on the NBM. Take a look at the NWS Billings AFD from 3 days ago and the note at the bottom: https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=AFDBYZ&e=202604081847 So certainly the SOPs for forecasting in the NWS have completely changed. Now we're basically hitting the "send" button on whatever the NBM comes up with. And I can't emphasize enough how BAD the NBM was this past winter in many of our snowstorms. It is inherently a poor model to forecast with when you have short term model disagreement OR when you are dealing with a 90th percentile or 10th percentile type storm. The NWS Mount Holly office was still forecasting 18-24 inches of snow the starting day of the late February snowstorm out in its western CWA. And sure enough nobody saw more than 4-5" of snow. Why did this happen? Because they relied on the NBM which lags in data and model cycles AND weights certain models. Forecasting accuracy will plummet in the NWS until they figure out how to better implement the NBM and/or develop it.

The wind right behind the low-topped line is gonna roar for some. KLNS is up to 45 mph sustained and gusting to 60 mph. Brother in Lancaster just lost power

Latest Day 2 from the SPC. 45-60% hatched wind for most, greatest tornado risk is just to the west across south-central PA where a 10-15% hatched risk is outlooked. Given the extremely high shear but low cape environment, damaging QLCS winds will be favored but there will be line mergers and perhaps a few lone cells capable of a stronger tornado. The failure modes I'm seeing are 1. Given the potency of the upper-level trough, there may be "too many" showers and storms developing and competing with each other pre-frontal 2. Early day clouds and showers will limit destabilization 3. Strong southerly winds may or may not create a localized "minimum" in severe weather across SE PA where a narrow marine layer could advect off the Chesapeake Bay Regardless, we haven't seen a severe weather event of this caliber in at least a few years. It will get very cold again behind the front, so make sure if you lose power you have a plan

Latest Day 3 from SPC. 45% wind probs just south of the Mason Dixon

Posted this down in the Mid-Atlantic thread, but the CSU machine learning forecast is still looking ugly for Monday. I do believe the greatest tornado threat will remain *mostly* south and east of the Mason-Dixon, but a damaging QLCS is still nothing to scoff at. Embedded spin-ups a real possibility too. Will need to watch how the system evolves over the next 2 days as there is still a non-zero chance this evolves more into a discrete supercell type event for SE PA. New Day 3 SPC comes out in 30 min

Latest 12z CSU-MLP forecast for Monday

They almost certainly have to do a rating for the Jan 25-26th storm, I'm very surprised it's not on there yet. I also just discovered they're including storms that impact areas outside the East Coast? I guess they have always done so if the storm impacts the Northeast in some capacity. December 2022 which was almost entirely uneventful for the East, outside of northern New England, is ranked 4th on the all-time NESIS scale for it's large snow footprint over the upper Mid-West and northern Plains. With that in mind, the January storm should be coming up soon.

From the NCEI site: NCEI is targeting a late-week release for the February 22-24, 2026 snow storm NESIS value.

From the NCEI site: NCEI is targeting a late-week release for the February 22-24, 2026 snow storm NESIS value.

Certainly far from a ratter winter, it's been cold and snowy and anytime you hit average snow it's better than most. Another storm though would elevate this season to an A+. This season was filled with "what ifs". We had probably 3 or 4 storm threats that never materialized, which makes the near to above average snowfall all that more impressive when you consider we missed out on some larger opportunities.

Same in Fleetwood, not even a dusting. Seasonal total is so far 34.25 inches which is near average for a winter season. Next Monday could be huge in the final winter grade for Berks.

They actually have 37.9" as of 7pm, shattering their previous record of 28.6. Still snowing as you said https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=RERPVD&e=202602240000

Also, remember that two things can be true at the same time here. This was an amazing, historic storm for many that lived up to expectations. But also a huge underperformer for others. This was never going to be a 1996 or 2016 that smacked almost the entire region in widespread 1-3 feet.

Gotcha, that's good to know I was looking at the PHL 7am report ha. It came down to wherever that western deformation band set up, which we knew would be the case. The NWS did very with far SE PA, Jersey, and Delaware. But NW burbs not so much. It just is what it is.

I've actually gotta agree with @LVLion77here. If we take a look at the NWS official forecast from yesterday morning, many many places busted significantly low on totals. I don't have their map right before the storm when they lowered totals, but I know even then they were too high in a lot of places west of 476. Based on this map: 24" in Mount Pocono? Last I saw they had 4". 15" in Reading? More like 4". Fleetwood was under a warning for 7-14" and we got 5. ChescoWX was in the 18-24" contour and he got 9-10". Even 20" in Philly center city will be too high. Overall Jersey did well, and they nailed the local max along the Jersey coast. None of this is to discredit the NWS of course, I'm not sure what else they could've done with the data on their hands yesterday morning. I know they'll go back and evaluate what went wrong and what they could've done better. I think there was obviously too much lean on the western NAM/HRRR/FV3 outliers. But the RGEM was ridiculously low on the far eastern side. If you're on this forum, you knew yesterday morning things were shifting back east and that totals would be significantly less so right then your expectations should've been with a modest plowable snow. If I'm the general public in Allentown and I looked at this map yesterday and planned for 15"? Well then yeah, I'd call it a bust. I think the NWS just went too high too soon and then played catch up last second.