ChescoWx

NW Chester County PA - A few flakes now and then but mainly moderate virga 

Temp 29.5

RH 81%

DP 24.4

Wind E 2 mph

Latest WXSIM with 6z data slightly upped snow amounts across NW Chester County PA - snow arrives by 9am with moderate snow by noon and heavy snow by 3pm - all over by 9pm with 3" to 5" total

WXSIM text forecast for East Nantmeal, initialized at  7:00 AM Jan 29, 2019
 _______________________________________________________________________________
 
 Today: Dense overcast. A chance of snow in the morning, then snow likely in the
 afternoon. High 32. Wind east-southeast around 5 mph in the morning, becoming
 south-southwest in the afternoon. Chance of precipitation 80 percent.
 Precipitation (liquid equivalent) mostly around half an inch. Snow accumulation
 2 to 4 inches.
 
 Tonight: Cloudy in the evening, becoming fair to partly cloudy after midnight.
 Patchy light fog. A chance of snow in the evening. Low 19. Wind west around 7
 mph, gusting to 17 mph. Chance of precipitation 60 percent. Precipitation
 (liquid equivalent) mostly less than a quarter of an inch. Snow accumulation
 about an inch.

WXSIM with 18z data trended down with qpf to now only 0.56" of liquid and 3" to 4" of snow

Tuesday: Dense overcast. A chance of snow in the morning, then snow likely in
 the afternoon. High 32. Wind southeast around 5 mph in the morning, becoming
 south-southwest in the afternoon. Chance of precipitation 80 percent.
 Precipitation (liquid equivalent) mostly between a quarter and half an inch.
 Snow accumulation 2 to 3 inches.
 
 Tuesday night: Dense overcast in the evening, becoming fair to partly cloudy
 after midnight. Patchy light fog in the evening. A chance of snow in the
 evening. Low 20. Wind northwest around 6 mph, gusting to 15 mph. Chance of
 precipitation 60 percent. Precipitation (liquid equivalent) mostly less than a
 quarter of an inch. Snow accumulation about an inch.

WXSIM with GFS/NAM 12z data is rock solid with 4" to 6" forecast - only difference is quite a bit colder this run than at 6z - has snow starting by dawn tomorrow and getting moderate by 8am with visibility forecasted down to 0.5 miles. Then S+ by 1130am with visibility under 0.2 miles. Snow should be all over by 10pm tomorrow night

WXSIM text forecast for East Nantmeal, initialized at 12:00 PM Jan 28, 2019
 _______________________________________________________________________________
 
 This afternoon: Partly cloudy. High 32. Wind east-northeast around 2 mph.
 
 Tonight: Partly cloudy in the evening, becoming cloudy after midnight. A slight
 chance of snow after midnight. Low 23. Wind southeast around 2 mph in the
 evening, becoming 5 mph after midnight. Chance of precipitation 20 percent.
 Precipitation (liquid equivalent) mostly less than a tenth of an inch. Little or
 no snow accumulation expected.
 
 Tuesday: Dense overcast. Snow likely. High 31. Wind southeast around 7 mph in
 the morning, becoming south around 3 mph in the afternoon. Chance of
 precipitation 80 percent. Precipitation (liquid equivalent) mostly around half
 an inch. Snow accumulation 3 to 5 inches.
 
 Tuesday night: Cloudy in the evening, becoming fair to partly cloudy after
 midnight. Patchy light fog. A chance of snow. Low 20. Wind west-northwest around
 6 mph, gusting to 16 mph. Chance of precipitation 50 percent. Precipitation
 (liquid equivalent) mostly less than a quarter of an inch. Snow accumulation
 about an inch.

Latest Wxsim with 6z data now has snow arriving by rush hour tomorrow morning in the NW Philly burbs. Total snow accumulation is now estimated between 4" to 6" before ending by 10pm tomorrow night. The current text forecast is below.

WXSIM text forecast for East Nantmeal, initialized at  7:00 AM Jan 28, 2019
 _______________________________________________________________________________
 

 Tonight: Partly cloudy in the evening, becoming cloudy after midnight. A slight
 chance of snow after midnight. Low 27. Wind east-southeast around 2 mph in the
 evening, becoming 5 mph after midnight. Chance of precipitation 20 percent.
 Precipitation (liquid equivalent) mostly less than a tenth of an inch. Snow
 accumulation about a quarter inch.
 
 Tuesday: Dense overcast. Snow likely in the morning, then a mix of snow and rain
 likely in the afternoon. High 33. Wind chill ranging from 22 to 27. Wind
 southeast around 6 mph in the morning, becoming south-southwest in the
 afternoon. Chance of precipitation 80 percent. Precipitation (liquid equivalent)
 mostly between half an inch and one inch. Snow accumulation 3 to 5 inches.
 
 Tuesday night: Cloudy in the evening, becoming fair to partly cloudy after
 midnight. Patchy light fog in the evening. A chance of snow in the evening, then
 a slight chance of snow after midnight. Low 20. Wind west-northwest around 7
 mph, gusting to 21 mph. Chance of precipitation 50 percent. Precipitation
 (liquid equivalent) mostly around a tenth of an inch. Snow accumulation about an
 inch.

16 minutes ago, Ralph Wiggum said:

Meso guidance (nams/rgem/srefs) are leaning heavily against flipping to snow and accumulation over an inch for many of us in SE PA. The globals are a quick flip to snow with SECS type accums 4-8"+ outside of  'extreme' SE PA along 95 particularly. 

Choose your weapon.....but choose wisely. 

Steve as you know be cautious with MESO at this range....not saying it doesn't happen but a little outside their range....be careful my man

Latest Wxsim with 18z data down to only 4" to 7" of snow but has eliminated any mixing potential and now sees an all snow event

Monday night: Partly cloudy in the evening, becoming mostly cloudy to cloudy
 after midnight. A chance of snow after midnight. Low 27. Wind east-southeast
 around 4 mph. Chance of precipitation 30 percent. Precipitation (liquid
 equivalent) mostly less than a tenth of an inch. Snow accumulation about a
 quarter inch.
 
 Tuesday: Dense overcast. Patchy light fog in the afternoon. Snow likely. High
 32. Wind southeast around 7 mph in the morning, becoming west-southwest around 3
 mph in the afternoon. Chance of precipitation 80 percent. Precipitation (liquid
 equivalent) mostly between half an inch and one inch. Snow accumulation 3 to 5
 inches.
 
 Tuesday night: Cloudy in the evening, becoming fair to partly cloudy after
 midnight. Patchy light fog in the evening. Snow likely. Low 20. Wind northwest
 around 8 mph, gusting to 19 mph. Chance of precipitation 60 percent.
 Precipitation (liquid equivalent) mostly less than a quarter of an inch. Snow
 accumulation 1 to 2 inches.

By the way if you are a snow weenie imagine how you would feel in Boston with only 1.8" of snow so far this year....our area has had 10x their snow this season.  At Logan Airport they are almost 20" below normal through today. Here in NW Chesco we have had 8 times the snow that Boston has seen so far. I was actually up there this week for a client in Waltham (West of BOS)  and they had about 4" of solid snow/IP on the ground although it was raining and warming. What was on the ground was the only event they have had this year.

7 minutes ago, Ralph Wiggum said:

Euro with either the coup or another Ucy head fake. Has 4-7" up here Tuesday. Of course I will be away in S NJ si lock it up and bank on it.

Starting to look like the ole Wxsim....

Latest EURO also starting to look like WXSIM....may start seeing a bit more interest here soon....

Wxsim with 12z data bumps up snow in NW Chesco to 6" to 8"

Tuesday: Dense overcast. Patchy light fog in the afternoon. A mix of snow,
 sleet, and freezing rain likely in the morning, then a mix of snow and rain
 likely in the afternoon. High 34. Wind southeast around 9 mph in the morning,
 becoming southwest around 4 mph in the afternoon. Chance of precipitation 80
 percent. Precipitation (liquid equivalent) mostly around an inch. Snow or ice
 (on ground) accumulation 4 to 6 inches. Little if any freezing rain accumulation.
 
 Tuesday night: Cloudy in the evening, becoming fair after midnight. Patchy light
 fog in the evening. Snow likely. Low 20. Wind northwest around 9 mph, gusting to
 19 mph. Chance of precipitation 60 percent. Precipitation (liquid equivalent)
 mostly around a quarter of an inch. Snow accumulation 1 to 2 inches.

Wxsim with 6z data for NW Chester County PA remains firm on a minor 3" to 4" snow event with a battle between rain and snow during the day Tuesday transitioning to a period of Heavy Snow Tuesday evening before ending late.

Through today we have had 10.7" of snow which is 5.9" below our normal snow to date. I see no reasons despite the winter is over crowd (happens every year and oh yeah don't forget the sun angle argument that is coming to a forum near you soon - LOL!) growing louder by the day to give in to that chatter. I see plenty of cold intrusions with some warmer periods as mentioned above but certainly no winter is over looks. I continue to remind folks here just 2 significant storms at some point over the next 2 months would put many posters on here above normal for the year. I remain convinced this will indeed happen. Stay tuned plenty of cold and storms to track!

Latest Wxsim with 18z data down a bit but still showing about 4" of snow with this event

Tuesday: Dense overcast. A chance of a mix of snow, sleet, and rain in the
 morning, then a mix of snow, sleet, rain, and freezing rain likely in the
 afternoon. High 35. Wind chill around 22. Wind southeast around 10 mph, gusting
 to 16 mph. Chance of precipitation 80 percent. Precipitation (liquid equivalent)
 mostly between half an inch and one inch. Snow or ice (on ground) accumulation
 around 2 inches. Little if any freezing rain accumulation.
 
 Tuesday night: Dense overcast in the evening, becoming partly cloudy after
 midnight. Patchy light fog after midnight. Snow likely. Low 18. Wind chill
 ranging from 12 to 23. Wind west around 11 mph, gusting to 22 mph. Chance of
 precipitation 70 percent. Precipitation (liquid equivalent) mostly between a
 quarter and half an inch. Snow accumulation around 2 inches.

3 minutes ago, ChescoPaWxman said:

WXSIM updated with 12z GFS updated with 12z NAM - n

Monday night: Mostly clear in the evening, becoming cloudy after midnight. A
 chance of a mix of snow and rain after midnight. Low 26. Wind chill ranging from
 19 to 29. Wind southeast around 6 mph. Chance of precipitation 30 percent.
 Precipitation (liquid equivalent) mostly less than a tenth of an inch. Snow
 accumulation about a quarter inch.
 
 Tuesday: Dense overcast. Patchy light fog in the afternoon. A mix of sleet,
 freezing rain, snow, and rain likely in the morning, then a mix of snow, rain,
 and sleet likely in the afternoon. High 35. Wind chill ranging from 22 to 28.
 Wind south-southeast around 7 mph. Chance of precipitation 80 percent.
 Precipitation (liquid equivalent) mostly around an inch. Snow or ice (on ground)
 accumulation 3 to 5 inches. Above-ground freezing rain accumulation up to 0.1
 inches.
 
 Tuesday night: Cloudy in the evening, becoming fair after midnight. Patchy light
 fog. Snow likely. Low 19. Wind west-northwest around 10 mph, gusting to 19 mph.
 Chance of precipitation 60 percent. Precipitation (liquid equivalent) mostly
 around a quarter of an inch. Snow accumulation 1 to 2 inches.

By the way I don not buy this at all - I am riding the EURO maybe up to 2" much more to the west

WXSIM updated with 12z GFS updated with 12z NAM - n

Monday night: Mostly clear in the evening, becoming cloudy after midnight. A
 chance of a mix of snow and rain after midnight. Low 26. Wind chill ranging from
 19 to 29. Wind southeast around 6 mph. Chance of precipitation 30 percent.
 Precipitation (liquid equivalent) mostly less than a tenth of an inch. Snow
 accumulation about a quarter inch.
 
 Tuesday: Dense overcast. Patchy light fog in the afternoon. A mix of sleet,
 freezing rain, snow, and rain likely in the morning, then a mix of snow, rain,
 and sleet likely in the afternoon. High 35. Wind chill ranging from 22 to 28.
 Wind south-southeast around 7 mph. Chance of precipitation 80 percent.
 Precipitation (liquid equivalent) mostly around an inch. Snow or ice (on ground)
 accumulation 3 to 5 inches. Above-ground freezing rain accumulation up to 0.1
 inches.
 
 Tuesday night: Cloudy in the evening, becoming fair after midnight. Patchy light
 fog. Snow likely. Low 19. Wind west-northwest around 10 mph, gusting to 19 mph.
 Chance of precipitation 60 percent. Precipitation (liquid equivalent) mostly
 around a quarter of an inch. Snow accumulation 1 to 2 inches.

Latest Wxsim with 12z NAM and 6z GFS showing 5" to 7" snow by Late Tuesday Night

Monday night: Clear in the evening, becoming partly to mostly cloudy after
 midnight. A slight chance of snow after midnight. Low 25. Wind chill ranging
 from 19 to 30. Wind east-southeast around 5 mph. Chance of precipitation 20
 percent. Precipitation (liquid equivalent) mostly less than a tenth of an inch.
 Snow accumulation about a quarter inch.
 
 Tuesday: Dense overcast. Patchy light fog in the afternoon. Snow likely in the
 morning, then a mix of snow and rain likely in the afternoon. High 33. Wind
 chill ranging from 20 to 26. Wind south around 7 mph. Chance of precipitation 80
 percent. Precipitation (liquid equivalent) mostly around an inch. Snow
 accumulation 4 to 6 inches.
 
 Tuesday night: Cloudy in the evening, becoming fair after midnight. Patchy light
 fog after midnight. A chance of snow in the evening. Low 17. Wind chill ranging
 from 12 to 21. Wind west-northwest around 10 mph, gusting to 19 mph. Chance of
 precipitation 60 percent. Precipitation (liquid equivalent) mostly less than a
 quarter of an inch. Snow accumulation about an inch.

JB on the Euro weeklies

For the time of the year, this is the coldest run I have seen on a European Weekly. Again, the nature of ensembles is to wash out extremes in the longer term, so it is impressive. We will be very dry in the eastern Indian Ocean over the next 40 days. There is increased precipitation shown for the last week of the forecast period, which would mean we put a 15-day clock on the winter after that, That would take us past March 15, and this should start breaking down then anyway.

This is as bullish of a run as I have ever seen in a late January ensemble, running the table into mid-March. I am almost certain the temperatures will support our overall idea, but we will find out soon. The mid-February to mid-March period, though centered farther to the southeast and later in the season, could be as impressively cold against averages as the January 15-February 14 period is likely to turn out over the Heartland (Midwest, Great Lakes and mid to upper Mississippi Valley). I suspect it will be more in line with the February forecast we have out.

19 hours ago, zenmsav6810 said:

His false positive rate is certified weenie.

To be fair JB and WB have done probably the best job with their winter outlook (with the exception of snow in the PHL to BOS corridor) otherwise their above normal mid-atlantic snows and cold centered over the midwest and east look spot on. Like I said you can nail a pattern correctly and I would say for sure our area will be biased cold for at least the next 7 weeks with multiple winter storm chances...now each of those may cut west and we get rain - but the overall pattern was nailed IMHO. Keep in mind a couple big snow events and folks in the PHL to NYC area will be near to above normal - even as crappy as the snow season has been we are at 75% of normal with 10.7" of snow so far...keep the faith my friends - faith will be rewarded!!

51 minutes ago, penndotguy said:

Either way interesting times ahead!!

Seems like we've been saying that for weeks now. I fear those times aren't really coming 

I guess I'm different than most on here - I enjoyed the tracking last week...even if it did not end in a big snow event. I believe we will have several more of these to track during the late Jan- Early March period - so much more active than last year when nothing happened during this mid-winter stretch. That said no one can say if any of these end in snow in everyone's back yard but I do believe there are many more storms and rumors of storms to track. So for me it has been and I believe it will be interesting times. But, I understand for probably many on here they have no interest in tracking a winter storm if it only results in a mix or mostly rain.

7 minutes ago, The Iceman said:

I think Ji has more credibility than him at this point... Used to be a fan but have come to realize he will always call for cold and snow because that's what sells.

As long as you understand his bias when forecasting - he is quite good with pattern recognition and you will never ever be surprised by a snowstorm! LOL!!

Either way interesting times ahead!!

JB still keeping an eye on the weekend early week event - says although modeling not there yet - he thinks something will come out of gulf and could be "spectacular"....

Should be an interesting week of tracking as it looks like a true Miller A could be coming up out of the gulf late next weekend or early week. It has been a while since we have had one of those. Now, of course the ultimate track will determine precip types. From this far out I favor a coastal hugger with Snow to rain and big snows well inland. The operational EURO right now has snow for the Jersey Shore but others bring it almost over ACY....

AM Low in NW Chesco was 6.4 - low wind chill today so far today has been 13 below. Nowhere close to record levels for Chester County. Today's record low was 11 below on this date back in 1984.

Little snow shower with the sun out here in NW Chesco with the temp down to 34.9 wind gust as high as 20mph so far

0.5" of snow and IP yesterday before change to rain - Total rain 1.51" with 0.81" since midnight - total snow for the season now up to 10.7" which is 1.5" below our normal snow through today.

The true push of cold advection has not begun as temps are still slowly rising now at high for the day of 41.2 - this will change soon