MAG5035

The 30 minute trip up to the 3100’ summit at Blue Knob certainly did not disappoint. Got an 11 and a 12” measurement. Drifting had been pretty significant up there during the height of the event.

1.2” was the best accum measured at the house today. Surface temps were just a couple degrees too warm in the early afternoon when the best snow rates were falling before transition to rain. Been mostly rain/white rain for a bit now with up to 0.85” for the day in precip. Currently about 36ºF. I spent the morning on Tussey Mountain in NW Huntingdon Co for the last day of archery and by mid afternoon there was likely 4-6”+ above 1800’ on that ridge, esp towards State College. This is still ongoing in the Laurel’s, might have to make the 30 minute drive to the top of Blue Knob to see the situation up there. I bet there’s monster totals at that elevation.

Temp is down to 40ºF here with 0.43” of rainfall and a high gust as measured by my weather station at 33.3mph. Things definitely are still are track for this Thurs night/Friday event. Timing seems to be Friday morning to later Friday afternoon for the non upslope enhanced precipitation associated with the low itself. All things considered computer models have been very consistent with each other the last few days with the evolution of this system. What I’ve noticed with the latest couple runs is the surface low is now being progged to backtrack all the way around the ring to make it into eastern PA, with the very deep 500mb low basically centered on PA for a time now. Basically this lends more support to potentially seeing a period of snow even into most/all of the Sus Valley now.. with elevation driving the level of success of any accums. The main part of this event as mentioned likely centers on Fri morning-afternoon as modelling has been progging the main wave of precip as a sort of spiral arm off the backtracking low pressure. It’s going to be interesting to see this unfold, as it’s a bit of a unique setup. The backtracking nature of this system lends to an actual example of a fujiwhara effect. Looking beyond, yes Thanksgiving/Thanksgiving Weekend has my attention. A storm had been showing up on op models in this timeframe in various forms more often than not on despite the range the last couple days even before today. So storm signal was already there, but they really upped the ante today. Ensembles are starting to see it a bit too. System progged for mid-week looks to be a key to maybe setting the boundary as well so we’ll see where things head the next few days with this. There should be plenty of cold on the playing field with the right setup.

The key to this making for any kind of semi interesting wintry action off of the aforementioned mountains is how far the coastal low retrogrades back toward C-PA. There’s a finite window of opportunity with this. Low is progged to be stacked, so there will be a cold core centered on the low that could deliver barely a cold enough low level column for a period of snow in lower elevations. The 500mb trough/low itself is highly anomalous for this time of year. Given how marginal temps will be, the closer this backtracks toward C-PA the better the chance of that. Once the closed off low and associated cold core starts tracking away, we lose the marginally cold column temps at the lower levels. Really initial thoughts for C-PA… I don’t really expect much in the Sus Valley, but it could certainly mix for a time or even be a period of snow with any minor accums relegated to the ridges down there. Surface temps would figure to be the biggest issue of all the C-PA regions. Models have been progging a good bit of backlash precip, and that is the other part of the equation. Westerly component would make downsloping an issue off of the Laurels to some degree, especially down in the LSV. Trying to size up this threat for the central counties.. as it could be quite variable. Anyone in the AOO/UNV/IPT corridor probably sees an all snow period Thurs night into Friday, but likely a highly elevational component as far as accums. I could see the Seven Mountains region and the first few major ridge lines past the Allegheny front seeing advisory amounts above a certain elevation (likely >1800ft). The valleys probably see more like a coating to an inch or so. Definitely looking at an advisory type event in the Laurels/western Mountains and I expect headlines in Cambria/Somerset/possibly Clearfield, Elk, etc eventually. The highest Somerset elevations has a shot of seeing warning totals. Given progged track of the coastal this could be a snow bomb for the higher Poconos elevations as well.

Certainly the prospects for the first accumulating snowfall of the season look quite high for the higher elevations of western PA as well as the Poconos given progged evolution of that retrograding low. There’s some indications this could be a bit more prolific than a typical couple of inches at elevation type of first upslope snow event. There’s two aspects of this event.. first the initial passage of a very vigorous shortwave that will be accompanied with hopefully a period of rain and then a strong frontal passage that could turn the mountains to some snow at the end Wed night into Thur. The second aspect is the carving out of a highly anomalous 500mb trough and closed low Fri/Sat which will set up a longer duration period upslope/LES as well as potentially some precip associated with the low itself as it meanders/retrogrades just north of C-PA. Main model difference at the moment appears to be thermals. Euro is warmer on the column overall by a few degrees than the GFS, which could be the difference between the Laurels seeing a few inches that is more elevation dependent within that zone (above 2k for example) and an upslope event that delivers a much bigger event to most/all of the Laurels as well as some elevation dependent accumulating snows that expand into the central counties with first flakes that are seen in most of C-PA. More certain is further south in the elevations of WVA, which almost double up the elevations of most of the Laurels. That is going to be a big upslope snow event down there. It’ll be interesting to see what happens, this type of setup has been somewhat rare as of late. The Laurel’s region of PA has had some of the highest % departure from average snowfall of anywhere else in PA the last several winters and a big part of that is from a lack of these NW flow/upslope setups.

To add to this, the EPO and WPO are both slated for a massive reversal to highly negative this week on the major ensembles… and staying negative out through the rest of their runs. That’s going with a generally negative NAO throughout as well. Only nitpick I really have is PNA staying mostly negative (GEFS eventually tries to get it positive).. which may weigh the cold air on the playing field in western Canada toward the western US at least initially. Either way, there is definitely a window of opportunity presenting itself from the last week of November into the opening week of December with what appears to be a decidedly more active pattern. I’m a bit late to the winter commentary in terms of thoughts on how things are going to go overall. Obviously the very highly negative PDO looms large with the gloomier aspects of our snow prospects. But what is not looming large is the ENSO. Forecasts in the spring for a moderate to strong Nina by this time of the year were much too robust and as of last week’s weekly ENSO report we still remain ENSO neutral (3.4 is at -0.3ºC). A stronger, established Nina coupled with the very -PDO state would have implied MJO spending a lot of time in the bad phases during the business end of winter. A neutral ENSO (or perhaps one that eventually transitions to a weak Nina) could present more favorability from the MJO realm.. at least at times. NAO blocking could be a wildcard too. 20-21 actually had the strong -PDO as well as a moderate Nina but that ended up being a decent winter here with the big hitters in mid December and beginning of Feb. There was a good bit of help from the NAO that winter. So I’ll acknowledge we likely have more of an uphill battle for getting at least an average winter, but I’m going remain cautiously optimistic with low expectations. I’ll go out on a limb to say I think we have more opportunities overall than last winter setup wise… but whether we capitalize on them is another story. Scoring something right out of the gate next month would certainly improve the prospects of respectable numbers for the winter.

We might not have to look too far in the future for wintry precip in C-PA by the way. While likely to be relegated to the north-central and Laurels, the overrunning precip slated for arriving Thurs morning is being portrayed as freezing rain (Allegheny Front and some of the ridge lines in the ridge and valley) and perhaps a period of snow (primarily higher north central) on some models. This was mentioned in the AFD this morning.The NAM and GFS (until todays 12z) has been hinting at this the last couple runs. The Euros thermals are debatable even though it shows mostly rain. The setup is there in terms of having some cold air damming with high pressure north of Maine and the approaching weakening surface low. How far temps drop Wed night will figure into any ZR. Otherwise, how much column temps cool at the onset of the overrunning will dictate any snow potential. Again, this potential is primarily in the north-central.. but still a reminder we’re not very far off from more wintry things.

Up to 0.48” on the event so far here. It’s been awhile since we’ve had a 44ºF synoptic rainfall. While we’re going to need a couple decent rain events to start to address the longer term hydro issues in areas that have been under more significant drought conditions (mainly in the SW and SE parts of the state)… this rain should put an end to what had been a very high wildfire threat not often seen around here. The combo of the near record to record dry October and the remaining dead leaves falling/dying or dead forest undergrowth really made a unique setup for having several bigger wildfires which were likely mainly caused by careless burning this past week with the windy/dry weather. I’m eyeing some more wholesale changes to the weather pattern in the 11/20-25 range as we get towards Thanksgiving week. Way out there yet but modelling has been showing variations of a more significant weather system/amplifcation in that timeframe perhaps ushering in the first stretch of more wintry temperatures and perhaps first flakes. The pattern does at least look more active in the meantime as well, with one or two rain chances showing.

KAOO appears to have already eclipsed its daily record of 78ºF set back in 1950 (topped 79ºF a bit ago). UNV’s daily record also set in 1950 is 81ºF and it’s “only” been about as high as 77ºF so far today so that one may still be safe. Here at the house it’s been as high as 79ºF and currently at 78ºF. Quite breezy today as well.

The potential of that is on the table. Certainly the opening 10+ days of the month look very warm…probably to the point where it’ll be hard to reverse what will likely be sizeable + departures even if we have a normal or colder than normal regime set up later on in November. We need a major shakeup in things to get the ball rolling toward some kind of a different pattern. We’ve had frontal passages and such but not any kind of major systems so far this fall that could be a catalyst to driving a more meaningful pattern change.. hence the persistent lack of rainfall here and the relatively stagnant pattern. Not really seeing a change in that status quo on modelling currently. MJO poised to make an 8-1-2 run, which figures to keep the tropics alive for potential late season activity in close near the US from that realm. Even with that, the mid latitude pattern doesn’t really look too conducive to yanking something like that up to juice up some kind of major system either. Eventually that change will come, but how long it takes will determine whether a really warm front part of November turns into the warmest one overall.

Absolutely incredible viewing tonight. From the top of Tussey Mountain (NW Huntingdon Co) in Rothrock State Forest the aurora and its colors were easily viewable with the naked eye. With the moon having set earlier you couldn’t have asked for better sky conditions. Pics were taken about an hour ago. iPhone 15 Pro with 3-10 second exposure and no edits. I also got good videos of it moving and pulsing. f

I was just about to post, the aurora is already visible here. Gonna be a fantastic night to view it.

A lot of times a weakening storm won’t do as well at tapping the winds aloft to the surface, especially with dying or disorganized convection around the core. A deepening storm with explosive convective development are where you see the very high winds aloft translated to the surface efficiently. Every major hurricane is kind of unique in what it ultimately does in terms of wind/surge impact and how widespread the impacts are. Currently, the wind field of Milton is very confined.. owing to an extremely tight pressure gradient to go with its exceptionally low pressure. The 5pm advisory estimated the hurricane force wind field out only 25 nautical miles from the eye in all 4 quadrants, and 40 nautical miles for >50kts. TS force winds on 3/4 quadrants are 70-80nm with the NW quadrants out to 120nm. If this storm were impacting Florida right now in its current state, there would obviously be extreme damage and surge where the core of the storm impacted, but the absolute worst would be really confined. A “weaker” hurricane of this nature becomes a larger one. Instead of the extremely tight pressure gradient we have now, that pressure field expands and hence expands the wind field. When this is getting to the FL coast it could be one of those cases of maintaining a very low central pressure (for example a high end cat 4 pressure), but not necessarily focused cat 4-cat 5 winds. With that type of structure change could come a much larger field of weaker (but still destructive) hurricane force winds.. which would boost storm surge potential over a much bigger area along with the wind damage impacts. Time will tell how this eventually evolves with it’s structure, and if the forecast shear can weaken this more than expected in a better case scenario.. but this needs to be taken very seriously anywhere where there’s mandatory evacuations. The angle of attack of this coming eastward into the west coast of FL is a very bad one regardless when it comes to surge.

Have a feeling Steelers/Cowboys has a good chance at getting a lightning delay either prior to kickoff or early in the game with the incoming line of storms.

There certainly hasn’t been any kind of prolific rain rates, but today is the ninth consecutive day of recording measurable rainfall here… totalling 3.2” since 9/23.