ChescoWx

As has been the case for this early winter season here in Chester County it appears we will see below normal temperatures for the upcoming week but then a brief but sharp warm up just in time to turn any brief snow at the start to a heavy rain on Thursday. For those who want snow we need these low pressure systems to track off the coast to our east to keep the cold air locked in. After the storm we will turn sharply colder by Friday PM with our coldest weather of the season so far on tap for Christmas weekend. Christmas eve day may struggle to escape the low to mid-20's for high temps.

Yep lock that up a White Christmas in Chester County...

Some interesting climate data analysis by month for Western Chester County PA. I wanted to see the differences in our local county climate comparing NWS coop observations taken at 340 ft above sea level (ASL) which were recorded from January 1894 through 1982 (89 years) vs. the observations that have been recorded now for the last 40 years at over 660 ft ASL. Some results that might be surprising to some. Overall very little change in our average temperatures since the 1890's +0.7%. However, somewhat cooler warm season months and warmer cold season months. The biggest differences have been in increased precipitation +9.7% and increased snowfall by 14.1%.

Quiet but seasonably chilly stretch of weather on the way through Wednesday. Then as the National Weather Service is saying this morning "Stay tuned for changes to the forecast, and our area should prepare for anything from heavy rain and gusty winds with some coastal flooding to snow and ice Thursday into Friday, with a very cold airmass likely to follow for next weekend." Lots of model disagreements but expect to gain a bit more consensus by Tuesday AM. The record high for today is 62 degrees from 2000. The record low is 1 below zero from 1910. Daily rain record is 2.99" from 2000. The daily snow record is the 7.5" that fell in 1932.

climate has of course not changed....climate cycles change and we have gone from a cold to a warmer and now I suspect we are trending into another colder cycle. We have been in a much snowier cycle during the last 2 decades....it will return again. Patience!

The EURO does not look right at all!! A bomb to lakes does not make sense....this will shift east in future runs although not saying it will be enough to bring a SECSy finish!!

as expected Euro follows - the ex-US models. Still nice to see some relative high level consensus at this range as I am sure we will see some more big swings over the next 6 days! Buckle up!!

It should likely follow the ICON and GEM at this range - it will not be showing a hit IMHO - at least with this run.

A great song there with a weather influence....my personal weather inspired song is Rain by the Beatles....maybe the earliest rock song inspired by mind altering agents

How tired would my snowblower be if it shoveled model snow output?

GFS snow by 7am Christmas Eve morning

Rain will end this AM. We have picked up 1.51" of rain and melted snow so far along with the 0.3" of snow/sleet yesterday. Of note with this event we have now exceeded our normal annual rainfall here in Chester County of 50.21". It looks likely we will now have colder than normal weather to close out 2022. The exception could be if the east coast storm next week tracks like the latest European model is showing. In that case we would have a brief warmup and change any brief snow to rain next Thursday into Friday. The models will change again many times before then. The record high for today is 67 degrees set in 1971. The record low is also the earliest seasonal record of a below zero reading as on this date in 1917 we fell to 1 degree below zero. Record rain is the 1.80" today in 1902. Our record snow was just 2 years ago when we received 7.3" of snow.

Still raining so far 1.51" of rain and 0.3" of snow from event

Suspect many on this forum would sign up for the 12z GFS if you wish for our 1st White Christmas in 10 years

Still moderate ZR here in NW Chesco temp up to 31.7 - evergreens a bit droopy with some ice accretion

Starting to change to all freezing rain - 90% ZR and 10% IP temp up to 29.9 Just measured 0.3" of sleet/snow here in East Nantmeal

Remember the GFS is famous for suppression of east coast snow events...often up till 3 days before the event.

Snow starting to mix back in with the moderate sleet looks like this will be our 1st measurable snow/sleet of the season. All surfaces covered temp at 29.8

Over 30 accidents now reported on the Route 30 Bypass here in Chester County. Still snow and sleet mix all surfaces coated with a temp down to 29.9

A mix of snow and sleet has started here in NW Chesco in East Nantmeal Township with 30.1 degrees DP 22.8

Overall means show increasing chances of our 1st White Christmas since 2012. Either way it will be cold!!

Another chilly day today before clouds increase and snow and or sleet begin right after rush hour tomorrow morning. The NWS has a Winter Weather Advisory up for the area...but still some differences in forecasted snow totals. Best bet is up to 1" of snow....with more the further north and west you go. We should then see a quick change over to a wind swept heavy rain by early afternoon. Stay tuned for later updates. The record high for today is 65.3 degrees from 2015. The record low is the 4 above zero from 1989. Daily rain record is 2.06" from 1897. Daily snow record is the 8.7" that fell today in 1917.

The NAM for now has the low actually almost going right up the GS Parkway. If verification is a move 25 miles east - I would tug that thump of early accumulating snow down a bit into Chester County.....now if it is 25 miles further inland....really quick turn to rain. Either way rain should wash any accumulations away as far North as Tamaqua

My current idea IP to rain - Delaware and Eastern Chester 0.5" to 1.0" - Western Chester and Western Montgomery Counties 2-4” Northern Bucks and Lehigh Valley 5"-9” Poconos 7"-11" NE PA