wdrag

Wantage NJ - 8 S of High Point. Final 2.5". glaze on top. Still 28.4F at 4A. Thanks for joining this thread w your obs.  Walt

8 hours ago, sussexcountyobs said:

Just measured 2 1/4" here. Was wondering why it was snowing here when everybody else is going the opposite direction. My question to you is, what is rh? 

sorry for the delay. RH is relative humidity.  Models are generally very good at forecasting deep layered high humidity precipitation, but are not so good with precip at layers of high humidity below ~3000 feet (example when a dry slot cleans out the high humidity above 3000 feet). In yesterdays case, With still very high humidity trapped below the inversion, and probably a temperature of nearly -8C somewhere in that layer, and just a bit of lift (with the secondary developing near the coast-there was convergence here), fine snow may have been produced because snow generally needs to be generated with ice nuclei in a saturated layer of ~ -8C or colder.  Also, as a side bar...when precip is changed to rain by a warm layer aloft, it can refreeze to ice pellets (sleet), with a temperature of -6C below that above freezing layer, or to ice pellets by a deep layer of sub0C below the above freezing layer. Anyway, hopefully the first part of your message is answered and my reasoning is possibly not the only answer. 

Ditto on fine snow here in Wantage. 2.4 at 720P and 20.8F.  the snow means that that there is possibly only a shallow saturated layer of rh with lift in the -8C range causing the fine snow. 

59 minutes ago, hudsonvalley21 said:

21 degrees here with some light sleet. What's your thoughts Walt on us folks along the 84 corridor getting to around freezing especially after midnight when the precip over central  Pennsylvania works thru?

Doubtful above freezing.  still 20.3 F here in Wantage at this time.

Hi,

The following are two graphics that I think are useful in determining snowfall potential.  The first is the NWS ensemble probability for various amounts of snow and freezing rain.  In this case, for a local briefing I used the prob for snow exceeding 4", issued prior to 4am this morning by the NWS.  It ... and if you haven't seen or used this,  its good stuff.  It showed not that a great a chance for exceeding 4" along and s of I84. 

I also added a graphic for consideration:  Anytime the NAM FOUS has 0 or +C at T5,  it sleets or rains, barring excessive VV in the ideal dendritic growth zone (saturated -12 to 18C).  Anyway, here's a 00z/12 look at the NAM 3KM T section for HPN.  Note the modeled 0C aloft approaching HPN ~17z, when the sleet began mixing in.   If the model changes with time, that needs to be considered.  In this case, the warming aloft was pretty stout early on. 

I view both of these tools as helpful reality checks, especially NAM inside of 60 hours. 

Any questions?

Later, Walt

Wantage NJ 8 s High Point.  505PM report 2.2" snow sleet total. Pounding sleet right now. Averaging at least a tenth an inch of sleet/hour, since Noon. 19.8F 740"MSL

27 minutes ago, Snow88 said:

Very nasty outside

Moderate sleet and ice everywhere. People are having a tough time shoveling this mess.

In Brooklyn?  How much.  I presume going to school was okay?

Wantage NJ 8 s High Point. 230PM report 1.9" snow/sleet and T19F at that time.  T At 4PM still 19.9F.

Sussex NJ downtown 205pm last report from this location. 1.6” with 1.3 snow 805am/noon and 0.3 sleet since noon thru 205p.   Sleet continues 

Sussex NJ Downtown. 1.3”.  Changed to sleet around 1155AM

Wantage NJ 740' mil last ob here till ~220P.  5s-. small flakes so far.  insignificant at this time. 

6 minutes ago, IrishRob17 said:

Remember this will be an obs only thread.

20/8 near MGJ, cloudy. 

Agreed on obs only-..deleted my 755A post. S flurries B in Wantage NJ 805A.  I may not be updating my location between 840A-220P. 

If the moderators feel the current thread on discussing the threat is sufficient then just discard this.  I'll probably have something to start this around 5A or 6A/12. 

Good Monday morning all, Its Feb 11 and the modeling while not ideal for MECS, certainly bodes well for multiple events the remainder of Feb and probably the first week of March.  Some of those should have decent front end thumps of snow-sleet ( i know not enough for I95, but who thought 4-6" by tomorrow morning near PHL s NJ????  one model did--the GGEM have 3-4"+)  We know about tomorrow up here.  19th-20th might be halfway decent VA's to SNE, 22nd-23rd  and 25th-26th also ensembled (EPS/GEFS).  The EPS has an 80% chance for half a foot of snow in NYC by the end of the 26th... the ensembled storm track is showing signs of depressing slightly south with a possibly persistent colder flavor after the 17th.  In any case...the GEFS which tends to be more accurate on large qpf,  is flagging 4-5" of w.e. pcpn in NJ between tomorrow and the 26th. I believe it.  Frigid airmass covering MT/DKTS this month continues through the end of Feb and the warmer than normal far se USA continues a nice storm track here in the ne, albeit with the history of dealing with cutters (OH Valley not redeveloping fast enough of LI).  Still,  prospects look a little better, especially w MJO trending colder phases. I even think the -NAO is already trying to develop now (transitory) and modeling some slight suppression which should become a little stronger after the 17th.   It's more or less the next 3 weeks we have to do this.  Fingers crossed the modeling and southward drift are thee eventual reality. 911a/11

715P...still 32 MPO, MSV and High Point Monument...33F at 1500 ft in northern Sussex County.  Just not quite cold enough during the pcpn.  

Supposedly MSV light snow. still at 635P??  Unsure but freezing there. 

This post is unlikely to garner any ice reports, but if there are any, please post.  SPC HREF too cold by maybe 2 degrees.  Not impossible above 1500 ft in Sussex County, but I think unlikely, except maybe High Point?  Maybe there will be an ice report from Litchfield County, tho I realize that n CT reports probably belong in the New England forum.  459P/6

II would like to try to collect a few reports in one focused thread, of any ice hazards, and possible radial thickness on branches, (difficult to check at night). SPC HREF has elevation icing forecast. South of I-84, it tends to be a degree or so cold but n of I-84 the HREF tends to be very very good. Again, most of us may not have anything, and even here at 740'MSL in nw NJ, i could miss, but not far north of me..I expect elevation problems tonight. I'll clean up this opening note if reports start flowing. Thanks. 

Welcome to February and radiational cooling in nw NJ, Lows this morning 10 below, Pequest, Andover (12N),  15 below Sussex (FWN), 16-22 Below Sandyston and Walpack respectively, all in Warren and Sussex Counties of nw NJ.  My house (740'MSL in Wantage NJ, ~3 mi from FWN and 250' higher   only -2.  Ditto -2 at High Point.  This over 4" snow cover throughout.  Guidance (coldest MOS), missed Sussex by at least 7F.  I believe these subzero readings will occur again tonight, though probably 5 or 10F warmer. Still,  we're not quite out of this below normal cold airmass here.  I am also aware of the EC 2M 7-10Fbust for yesterday morning near CHI (uncommon in a well mixed environment).  At least it picked up on Rockford, and apparently per Joe Bastardi tweet, it got down to near ~ -38F in nw IL (unconfirmed coldest state record?).  Have a good day anticipating, after Feb 6 (ice events i84), or after Feb 14 (snow) as many have noted here.   A BIG test for FV3 vs the currently operational GFS from Feb 7 onward when the FV3 is much colder than its soon to replace GFS.  This one I want to remember (Feb 7-15 00z/06z versions).  I've seen FV3 miss date of events compared to the current GFS.  However, am informed that the FV3 is apparently better on on type than the GFS.  This I dont know. I may not break able top respond after 845A today.  By the way,  you're seeing infrastructure impacts now in the coldest parts of the country-watert mains.  Yesterday here in nw NJ... groups of trucks could not start early yesterday morning (subzero), delaying deliveries. 

For your post event summary... from NHSRSC. 

2 hours ago, LibertyBell said:

Maybe the colder air moving further east increases the chances of NYC getting to negative numbers this morning!

What I remember about Jan 1985 is that it hit -2 in NYC and it was the last time we had a high in the single digits.  Atlanta got down to -8 and it was -18 in the DC area!

There were several zero or below Arctic shots here in the early to mid 80s- Christmas 1980, Jan 1982, Jan 1985

I heard low was 2F at NYC CP this morning. Haven't had chance to verify and on the run now , but I hard only 4 days this cold in the past 30 years... heard from one of your favorite long rangers.  It is having impact here today.  Walt 

8 minutes ago, LibertyBell said:

Walt, I thought Jan 1985 was colder?  Chicago reached -27 for their low, and that was our best NYC Arctic outbreak that I can remember and also the coldest presidential inauguration day.

the 1980s were amazing for cold!

 

The min yes as you remember,  the mean no.  Here is an attachment.  Chicago definitely not making -27 this morning... cold core departed and EC appears terrible on its 2m there at this time. 

13 minutes ago, CIK62 said:

Last day of Jan. is averaging 9degs., or 24degs., BN.

Month to date is +0.9[33.3].    Should end Jan. at +0.1[32.5].

All 8 days are averaging 34degs.,  or just Normal.

EURO is 0" of Snow for next 10 days.    GEFS is 50/50 on 6" by the 16th.

RIP to both for now.

Yes on EC op for the next 10 days.  Of interest, and while it may be a tad cold...  potential substantial ice event nePA/nw NJ newd up I84 to MA 6th-7th, a climatologically very favorable period for winter storms in the Boston area.  So, no snow, ... but winter  ice hazard may be of interest for planners 6th-7th  FV3 I think is in that direction as well and supposedly FV3 already an advantage in testing, vs GFS in ptype.  I have no faith FV3, timing vs GFS.  

7 hours ago, donsutherland1 said:

In the wake of an Arctic front that brought a brief period of whiteout conditions to much of the region, bitterly cold air has sent the mercury tumbling into the single digits in a growing part of the area.

At 9 pm, the temperature in Central Park was just 9°. Earlier today, Chicago had a low temperature of -23°. That was that city's coldest reading sinc January 20, 1985 when the temperature fell to -27°. The high temperature was an icy -10°. That is only the fourth time on record that Chicago had a high temperature of -10° or lower.

The SOI was +3.02 today. While the MJO moves through Phase 6, the SOI could continue to retain positive values, as is currently the case. Afterward, it will likely return to negative values.

The Arctic Oscillation (AO) was -1.503. The preliminary average for meteorological winter is -0.230.

On January 29, the MJO was in Phase 6 with an amplitude of 1.577 (RMM). That amplitude had fallen fairly sharply from the January 28-adjusted figure of 1.985.

The MJO will continue to advance through Phase 6 and then move into Phase 7 within perhaps 1-4 days. Upon reaching Phase 7, its amplitude could decline toward low amplitude values. It remains uncertain whether the MJO will reach Phase 8 before it either reaches low amplitude values or possibly reverses to Phase 6. The risks of a turn toward Phase 6 or a drop to low amplitude prior to any move to Phase 8 have increased somewhat in recent days.

Nevertheless, the MJO will likely remain at a high amplitude into at least the first week of February. For the month as a whole, the MJO will likely be at a high amplitude (1.000 or above) for a considerable part of February. The MJO will likely remain at a predominantly high amplitude during February.

Following the shot of extreme cold, a period of moderation appears likely during the middle of the first week of February. The operational ECMWF, GFS, and EPS forecast high temperatures in the 50s during the February 3-5 period in the northern Middle Atlantic and southern New England areas. Farther south, parts of the Middle Atlantic region could experience a high temperature of 60° or above. Colder air should follow by the end of that week. There is a possibility that a predominantly colder than normal regime could then lock in for at least a 2-3 week period.

Good Thursday morning all,  For the record... Chicago yesterday, experienced its 2nd coldest day in its 145+ years of recorded history...  average T -16.5F   The coldest day was 12/24/83 avg -18F.  For what its worth, I was stationed at NWS MKE back in the 1980's severe cold snaps. Back then, if your car was not garaged in these -20sF outbreaks,  there was a good chance it would NOT start because of the oil congealing,  or battery failure. 3F/31 at 5A in NYC. ECMWF 2m temps have overall been better than the GFS  2m T in well mixed environments,  both CHI and NYC (though I could see a failure at CHI this morning, still tbd).  

Wantage NJ 8 S of High Point.  A brief sw/sw+ around 215-230P estimated 0.2" Season total 20.1