Monday 1/28 Winter Event

[Violentweatherfan]

You will not get anymore snow then you did on Friday. These events usually go quickly to rain, it's not going to be a big deal

+1 

[cast4]

You will not get anymore snow then you did on Friday. These events usually go quickly to rain, it's not going to be a big deal

That depends upon where you live. It's not all about snow.

[Voyager]

NWS really backed off on the frozen/freezing here. The thinking this morning was 1-3 inches of snow followed by sleet/freezing rain with a high of 31. Now it's this:

 

Monday: Snow and freezing rain before 11am, then freezing rain between 11am and 1pm, then rain after 1pm. High near 34. Light south wind increasing to 5 to 9 mph in the morning. Winds could gust as high as 21 mph. Chance of precipitation is 90%. New ice accumulation of less than a 0.1 of an inch possible. New snow accumulation of less than a half inch possible.

[RU848789]

Just posted this in the NYC forum, but perhaps this is a better place for it, since I live in the Mt. Holly CWA and my question is really about the NWS in Mt. Holly's forecast.  My comment is that I have never, ever seen the NWS in Mt. Holly put up winter weather advisories in Mercer, Philadelphia, Delaware and Newcastle (DE) counties and not have one up in Middlesex County (outside of systems, where the precip just wasn't going to reach that far north).  The point-and-click, text and graphical forecasts don't look appreciably different, so I just don't get it.  The AFD doesn't address this very unusual situation, either.  Would be interested to hear the rationale. 

 

[Isotherm]

Just posted this in the NYC forum, but perhaps this is a better place for it, since I live in the Mt. Holly CWA and my question is really about the NWS in Mt. Holly's forecast.  My comment is that I have never, ever seen the NWS in Mt. Holly put up winter weather advisories in Mercer, Philadelphia, Delaware and Newcastle (DE) counties and not have one up in Middlesex County (outside of systems, where the precip just wasn't going to reach that far north).  The point-and-click, text and graphical forecasts don't look appreciably different, so I just don't get it.  The AFD doesn't address this very unusual situation, either.  Would be interested to hear the rationale. 

 

 

 

There's also an advisory down to the city of Newark, making it even more unusual that Middlesex and Union have nothing. Soundings are no different really.

[Isotherm]

New Brunswick sounding is pretty wintry through Mon afternoon. Snow to sleet to ZR.

 

15Z, snow:

 

 

 

18z, sleet to ZR:

 

 

 

33F by 21z.

[JCT777]

"to me this is much more an intriguing weather event than the 4 hour light snow event that people flooded the board with observations as if they had never seen it snow before, it was quite funny actually"

As long as those who prefer snow over ice amuse you, they are doing their job.

But seriously, I for one much prefer snow to ice. And don't forget that the timing of Friday's event made the evening drive a mess for a lot of folks where over an inch fell. Likewise, of course, tomorrow's event could mess up the morning drive for many.

[chubbs]

The NAM has lowered frozen precip while GFS has gotten colder so model differences are reduced. Frozen precip is very light south of the LV. Don't expect much more than a dusting of snow and a light coating of ice on untreated surfaces.  

[Parsley]

to me this is much more an intriguing weather event than the 4 hour light snow event that people flooded the board with observations as if they had never seen it snow before, it was quite funny actually

 

Well, some of us witnessed 1/4 vis. +SN on Friday. Those of us flooding the board were probably seeing snow worthy of such posts. 2.3" of snow in 3-4 hours wasn't too shabby.....especially considering this winter.

[RU848789]

There's also an advisory down to the city of Newark, making it even more unusual that Middlesex and Union have nothing. Soundings are no different really.

 

But at least that might make sense (not considering the soundings) because Essex is essentially due north of Union and it's at least possible that makes a difference in an overrunning event with the changeover to rain proceeding from south to north.  But to have Middlesex County, which is 80+ miles northeast of Newcastle (and of course well NE of the SE PA counties with Advisories up) without a WWAdvisory in an overrunning event simply seems impossible.  I get that Middlesex is less inland than those counties, but this isn't a coastal system, where it's possible that being closer to the coastal storm's milder winds off the ocean can lead to a changeover here earlier than SE PA/Mercer, but I just don't get it in this type of setup.  I assume there's a good explanation - would like to hear it. 

[johnc]

But at least that might make sense (not considering the soundings) because Essex is essentially due north of Union and it's at least possible that makes a difference in an overrunning event with the changeover to rain proceeding from south to north.  But to have Middlesex County, which is 80+ miles northeast of Newcastle (and of course well NE of the SE PA counties with Advisories up) without a WWAdvisory in an overrunning event simply seems impossible.  I get that Middlesex is less inland than those counties, but this isn't a coastal system, where it's possible that being closer to the coastal storm's milder winds off the ocean can lead to a changeover here earlier than SE PA/Mercer, but I just don't get it in this type of setup.  I assume there's a good explanation - would like to hear it. 

 

I think it comes down to timing.  First on the fact that New Castle Co. is much more likely to get some wintry precip during the morning commute (and looking at the current radar, it appears that will be the case).  Winter Weather Advisories are more likely when the weather is expected during commute times.  The second aspect of the timing is that that area might be more likely to receive freezing rain, and as the AFD states, "even a trace of freezing rain warrants an advisory".

[johnc]

There's also an advisory down to the city of Newark, making it even more unusual that Middlesex and Union have nothing. Soundings are no different really.

 

Regarding Essex Co., the forecast seems to indicate that there will still be frozen precip. falling in time for the beginning of the evening commute.  For Middlesex and Union Cos. you have a changeover to rain by 3-4pm.  So they're kinda in the squeeze there.  Probably don't get into it for the morning commute like the southern areas do, and are over to rain before the evening commute unlike the northern counties.  Gotta draw the line somewhere. 

[phlwx]

Light snow to York and MDT at 3 AM.

[famartin]

But at least that might make sense (not considering the soundings) because Essex is essentially due north of Union and it's at least possible that makes a difference in an overrunning event with the changeover to rain proceeding from south to north.  But to have Middlesex County, which is 80+ miles northeast of Newcastle (and of course well NE of the SE PA counties with Advisories up) without a WWAdvisory in an overrunning event simply seems impossible.  I get that Middlesex is less inland than those counties, but this isn't a coastal system, where it's possible that being closer to the coastal storm's milder winds off the ocean can lead to a changeover here earlier than SE PA/Mercer, but I just don't get it in this type of setup.  I assume there's a good explanation - would like to hear it. 

 

I believe this excerpt from Upton's AFD explains what is going on with winter weather advisories (or lack thereof) in metro NYC (including the portion covered by Mt. Holly, since they coordinate):

INITIAL THOUGHT WAS LIGHT OVERRUNNING PRECIPITATION BEGINS MOVINGINTO THE WESTERN HALF OF THE CWA BY AROUND 15Z WITH INCREASINGISENTROPIC LIFT...SPREADING TO THE EASTERN PORTIONS OF CT AND LITHEN BY 18Z. WITH A COLDER AIR MASS IN PLACE...PRODUCING TEMPERATURESGENERALLY BELOW FREEZING...THE INITIAL P-TYPE SHOULD BEGIN AS SNOWEVERYWHERE. HOWEVER...AS WARM AIR ADVECTION SETS UP INCREASINGTHE LOWER LEVEL TEMPS...COULD SEE SLEET MIXING IN FOR A FEWHOURS MIDDAY ALONG THE COAST...THEN BECOMING ALL RAIN BY LATEAFTERNOON. SOUNDINGS INCREASE TEMPS A BIT TOO FAST...SO HELD OFFFROM TRANSITIONING TO ALL RAIN UNTIL AFTER 21Z FOR THE COASTALZONES. BECAUSE OF THIS TRANSITION...AND WITH MINIMAL SNOWACCUMULATIONS EXPECTED...DID NOT ISSUE ANY WINTER WX ADVISORIESFOR THIS AREA.

[RU848789]

I think it comes down to timing.  First on the fact that New Castle Co. is much more likely to get some wintry precip during the morning commute (and looking at the current radar, it appears that will be the case).  Winter Weather Advisories are more likely when the weather is expected during commute times.  The second aspect of the timing is that that area might be more likely to receive freezing rain, and as the AFD states, "even a trace of freezing rain warrants an advisory".

 

 

I believe this excerpt from Upton's AFD explains what is going on with winter weather advisories (or lack thereof) in metro NYC (including the portion covered by Mt. Holly, since they coordinate):

INITIAL THOUGHT WAS LIGHT OVERRUNNING PRECIPITATION BEGINS MOVINGINTO THE WESTERN HALF OF THE CWA BY AROUND 15Z WITH INCREASINGISENTROPIC LIFT...SPREADING TO THE EASTERN PORTIONS OF CT AND LITHEN BY 18Z. WITH A COLDER AIR MASS IN PLACE...PRODUCING TEMPERATURESGENERALLY BELOW FREEZING...THE INITIAL P-TYPE SHOULD BEGIN AS SNOWEVERYWHERE. HOWEVER...AS WARM AIR ADVECTION SETS UP INCREASINGTHE LOWER LEVEL TEMPS...COULD SEE SLEET MIXING IN FOR A FEWHOURS MIDDAY ALONG THE COAST...THEN BECOMING ALL RAIN BY LATEAFTERNOON. SOUNDINGS INCREASE TEMPS A BIT TOO FAST...SO HELD OFFFROM TRANSITIONING TO ALL RAIN UNTIL AFTER 21Z FOR THE COASTALZONES. BECAUSE OF THIS TRANSITION...AND WITH MINIMAL SNOWACCUMULATIONS EXPECTED...DID NOT ISSUE ANY WINTER WX ADVISORIESFOR THIS AREA.

 

Well, Mt. Holly finally explained their thinking in the 6 am update - appears it was all about a higher likelihood of freezing rain near the Delaware River counties in South Jersey/PA, since they extended the WWAdvisories to NW Burlington, Camden, Gloucester, and Salem Counties at 6 am, but left Middlesex out.  Don't think it had anything to do with timing vs. rush hour (plenty of traffic in Middlesex at 10 am, lol) or with what Upton was thinking, but could be wrong on that.  As an aside, they just canceled the advisories at 11:30 am for NW Burlington, Camden, Gloucester, Salem, eastern Chester, Delaware and Philadlephia Counties, as temps have risen above freezing in those locations.  Advisories are still up for Mercer and the NW Philly suburbs.  But not Middlesex, lol.  My whole issue wasn't that Middlesex should have had an advisory, but that I found it hard to believe we wouldn't while those counties to our S/W would - and the fact that most of them have been dropped kind of makes my point, IMO. 

 

THERE SHOULD BE SOME SNOW TO SLEET NEAR THE INTERSTATE 295 CORRIDOR

IN NEW JERSEY. SINCE IT COULD BE A BIT MESSY WITH EVEN SOME FREEZING

RAIN POSSIBLE, WE DECIDED TO ERR ON THE SIDE OF CAUTION AND GO AHEAD

AND ADDED IN NORTHWEST BURLINGTON, CAMDEN, GLOUCESTER AND SALEM

COUNTIES TO THE ADVISORY. THE END TIME WILL BE THE SAME AS

PHILADELPHIA, ALTHOUGH IT CAN ALWAYS BE TRIMMED BACK EARLY DEPENDING

ON HOW THE TEMPERATURES BEHAVE. AFTER TOSSING AROUND THE IDEA ABOUT

ADDING MIDDLESEX COUNTY, WE OPTED TO LEAVE IT OUT FOR NOW AS WE WERE

NOT COMING UP WITH MUCH IN THE WAY OF FREEZING RAIN HERE.