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NYC/Tri-State Area: Stumbling into January Disco


earthlight

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18z GFS continues with the cold and stormy theme in the mid to long range.

The 18z GFS has the PNA ridge returning after a brief relaxation in time for the January 7-8 threat:

post-475-0-08778000-1325375010.gif

In the long range, the GFS continues to insist on a strong Rex block over NW Canada/AK with an east-based -NAO retrograding into Greenland, setting up a beautiful high latitude blocking pattern:

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What bull****?

Ant I have H5 maps on my phone from november or early december and it had a -Nao a strong one at that and never happend,gfs loves to over do cold and make false patterns,thats why we call it "fantasy"hours.

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GFS may have drank a bit too much tonight, lol

That is usually the case in the long range anyway. Even better, the ensemble mean over the past 24 hours has decided to flip from +4 to +8 dm height anomalies over Greenland at the tail end of the run, to -12 to -18 height anomalies over Greenland at Day 10.

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Looping through this really gives you an appreciation of the cold air coming in the middle of this week. The NAM currently has forecast lows below 10 for some areas of New Jersey and in the teens for NYC. But with the forecast 850 temperatures and relatively light winds/clear skies forecast at 00-06z Wednesday...I would not be surprised to see readings several degrees lower than progs in the suburbs.

http://www.meteo.psu.edu/~gadomski/NAMSFC4_12z/8loop.html

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With thicknesses as low as they are, its probable the 00z NAM soundings would be more accurate and they dont get above 30 at all Tuesday.

I agree. It is going to be very interesting to see how low the interior locations can get. The NAM has been trending towards much lighter winds on Tuesday Night and Wednesday morning over the last several runs. Now they are forecast to be very minimal between 00 and 06z Wednesday. With clear skies, I think there is the potential for many interior locations to drop into the single digits.

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I agree. It is going to be very interesting to see how low the interior locations can get. The NAM has been trending towards much lighter winds on Tuesday Night and Wednesday morning over the last several runs. Now they are forecast to be very minimal between 00 and 06z Wednesday. With clear skies, I think there is the potential for many interior locations to drop into the single digits.

Agree, and I also think Tuesday's highs will likely top out around 25F in NYC, especially if the 00z NAM verifies. We've got 850mb temperatures falling as Tuesday progresses, with midday/18z values around -18c. Some of the coldest 850mb air we see around our area is in the -20 to -25c range (there have been cases colder, but for most severe cold events, it's this). Generally if we're talking full sunshine, the coldest NYC gets is 15-20F for highs. I honestly can't see much higher than 25F given the progged 850s and a chilling airmass as the afternoon progresses. Lows will not be in the single digits for the city as 850s are warming fairly rapidly overnight, wind direction is less than ideal (NW, whereas N is preferred) however, city temps still probable to be in the middle 10s.

Suburbia is a tough call as sfc high pressure is somewhat lacking to completely decouple the NWLY flow, although I do expect much of NW NJ to be sub 10, and 10-15 for most of NJ.

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Agree, and I also think Tuesday's highs will likely top out around 25F in NYC, especially if the 00z NAM verifies. We've got 850mb temperatures falling as Tuesday progresses, with midday/18z values around -18c. Some of the coldest 850mb air we see around our area is in the -20 to -25c range (there have been cases colder, but for most severe cold events, it's this). Generally if we're talking full sunshine, the coldest NYC gets is 15-20F for highs. I honestly can't see much higher than 25F given the progged 850s and a chilling airmass as the afternoon progresses. Lows will not be in the single digits for the city as 850s are warming fairly rapidly overnight, wind direction is less than ideal (NW, whereas N is preferred) however, city temps still probable to be in the middle 10s.

Suburbia is a tough call as sfc high pressure is somewhat lacking to completely decouple the NWLY flow, although I do expect much of NW NJ to be sub 10, and 10-15 for most of NJ.

Some of the warmer temperatures on Tuesday will come earlier in the day and possibly in the earlier afternoon. The NAM has slowed the arctic front so that on Tuesday between 09 and 15z, 850 temperatures are still between 12 and 16c. That could support temperatures in the mid or upper 20's. But with strong northwesterly winds, I think upper 20's is a better bet for an afternoon high than the NWS OKX 32 F. They may be going with an early morning high, too...the NAM has 12z Tuesday temperatures very near 30 F in NYC.

I also agree about the low temperatures not being in the single digits in the city. It's a shame, but we can't hold this cold air at all. By early Wednesday morning the best cold air is already gone. But it will probably still be enough to get some interior locations into the single digits with clear skies, relatively calm winds, and 850 temperatures near -20 C.

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Agree, and I also think Tuesday's highs will likely top out around 25F in NYC, especially if the 00z NAM verifies. We've got 850mb temperatures falling as Tuesday progresses, with midday/18z values around -18c. Some of the coldest 850mb air we see around our area is in the -20 to -25c range (there have been cases colder, but for most severe cold events, it's this). Generally if we're talking full sunshine, the coldest NYC gets is 15-20F for highs. I honestly can't see much higher than 25F given the progged 850s and a chilling airmass as the afternoon progresses. Lows will not be in the single digits for the city as 850s are warming fairly rapidly overnight, wind direction is less than ideal (NW, whereas N is preferred) however, city temps still probable to be in the middle 10s.

Suburbia is a tough call as sfc high pressure is somewhat lacking to completely decouple the NWLY flow, although I do expect much of NW NJ to be sub 10, and 10-15 for most of NJ.

Some of the real arctic outbreaks usually bring the -30 contour at 850mb to our doorstep.

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Domenica Davis just said: 'Bitter cold and snow in the forecast...' Okay, it may just meet the definition of bitterly cold, but in no way should she have said snow.

Attention grabbing headline, I guess they need to bring in some viewers as the weather has been incessantly boring.

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Some of the warmer temperatures on Tuesday will come earlier in the day and possibly in the earlier afternoon. The NAM has slowed the arctic front so that on Tuesday between 09 and 15z, 850 temperatures are still between 12 and 16c. That could support temperatures in the mid or upper 20's. But with strong northwesterly winds, I think upper 20's is a better bet for an afternoon high than the NWS OKX 32 F. They may be going with an early morning high, too...the NAM has 12z Tuesday temperatures very near 30 F in NYC.

I also agree about the low temperatures not being in the single digits in the city. It's a shame, but we can't hold this cold air at all. By early Wednesday morning the best cold air is already gone. But it will probably still be enough to get some interior locations into the single digits with clear skies, relatively calm winds, and 850 temperatures near -20 C.

Yeah, very reminiscent of 07-08 with 24-36 hour shots of cold air followed by rapid moderation. Good point regarding the 15z temps; we may peak at 27 or 28 around 11am before slipping into the mid 20s for the afternoon. Either way, we agree the 32F is likely 5 degrees too warm.

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