January 2018 Discussions & Observations Thread

[jconsor]

1 hour ago, CIK62 said:

Next 7 days (Remainder of Jan.) averaging 36degs., or 4degs. AN.

Month to date is  -2.0degs.  

We should end month at  -0.65degs.   This means that while the first 10 days were -11.4, the next 21 days were +4.3.

 

The 8 day period is 4 to 5degs. AN.

Next 7 day forecast is tricky with a few midnight highs and midnight lows.

Here's my forecast for NYC Central Park next 7 days:

Jan 25 35/23 (low this morning so far was 23F)
Jan 26 40/24
Jan 27 52/35
Jan 28 50/40
Jan 29 42/32
Jan 30 32/20
Jan 31 34/18

Average: 40.7/27.4 = 34.1

The average for Central Park these 7 days is (rounded) 39/27, so if my forecast verified, these 7 days would be only around 1F above normal.  We'll see.  I would consider a near normal stretch in the midst of such an extended overall warmer pattern to be rather impressive.

[bluewave]

NYC continuing the theme of the greatest January thaw on record following a first week which averaged below 20 degrees.

Coldest first week of January....monthly average...# of 50 and 60 degree days

#1...1918...14.6....21.7...1 day of 50 or over

#2...2018...16.4...30.4 and rising...6 days of 50 or over and 2 days 60 or over...so far

#3...1904...16.9...25.3....2 days of 50 or over

#4...1879...18.7....26.9...1 day of 50 or over

[uncle W]

the average January monthly temp from 1981-2010 is 33.0 in Central Park...it's 33.1 since 1980...NYC was 30.4 as of yesterday...

[CPcantmeasuresnow]

59 minutes ago, uncle W said:

the average January monthly temp from 1981-2010 is 33.0 in Central Park...it's 33.1 since 1980...NYC was 30.4 as of yesterday...

At this point in time what is the average for January 1991 through January 2018?

I'm just curious how much the new 30 year January look to increase or decrease (doubtful) when the new averages are calculated in 3 years.

[bluewave]

Looks like an MJO 7 gradient pattern setting up for early February with the battlezone between cold and warm close to the East Coast. Should feature  a back and forth between AN and BN days here. We'll probably need the MJO to head for phase 8-2 in order to finally pull the trough into the East for mid-February and beyond.

http://wx.graphics/

 

[uncle W]

2 hours ago, CPcantmeasuresnow said:

At this point in time what is the average for January 1991 through January 2018?

I'm just curious how much the new 30 year January look to increase or decrease (doubtful) when the new averages are calculated in 3 years.

IF IT KEEPS UP THE SAME PACE IT WOULD BE 33.7..THE 1980'S AVERAGED 31.3...1961-1990 AVERAGED NEAR 31.3...

[SnoSki14]

2 hours ago, bluewave said:

Looks like an MJO 7 gradient pattern setting up for early February with the battlezone between cold and warm close to the East Coast. Should feature  a back and forth between AN and BN days here. We'll probably need the MJO to head for phase 8-2 in order to finally pull the trough into the East for mid-February and beyond.

http://wx.graphics/

 

Which is why it could take until Feb 10-15 for sustained BN temps. 

It does look active though but gradient patterns are a lot more generous for New England than us. 

[White Gorilla]

6 hours ago, donsutherland1 said:

Despite bright afternoon sunshine yesterday, the temperature fell from 41° at noon to 35° by 5 pm and then 27° by midnight as a fresh surge of colder air moved into the region. The arrival of January’s latest cold air mass interrupted the thaw that had predominated through much of the second half of the month. As a result, the probability that January will wind up colder than normal as a whole continued to increase.

New York City’s Average Temperature Through:

1/24: 30.4° (2.0° below normal)
1/25: 30.2°-30.5° (1/24 estimate: 30.4°-30.6°)
1/31: 31.0°-32.1° (1/24 estimate: 31.1°-32.5°)

Per aggressive sensitivity analysis, the estimated probability of a below normal monthly anomaly: 62% (1/24 estimate: 60%)

Winters that feature severe cold in early January, followed by a pronounced thaw, and then a return to severe cold afterward have occurred from time to time in the northern Mid-Atlantic and southern New England regions. The following is an account from Philadelphia:

The winter of 1783-4 was extremely cold, and the ice very thick. In the month of January a thaw came on suddenly, which set the ice afloat: suddenly again the weather became intensely cold, so as to obstruct the floating ice, which was formed into heaps, or dams, across the [Susquehanna] river.

Far more recently, the La Niña (PDO+) winter of 1995-96 provided an example. On January 5-6, New York City saw low temperatures below 10°. By January 18, the high temperature rose above 50°. On January 27, the temperature reached 54°, its last 50° maximum figure of the month. A few days later, on January 30, the pattern shifted toward a colder one. Severe cold returned in early February. On both February 4 and 5, the high temperature reached only 17°. The winter’s coldest temperature, a minimum reading of 5° occurred on February 5. In addition, 12.7” snow fell after February 5, including 9.9” on February 16. March would go on to register three additional 4” or greater snowstorms. The back of the long winter of 1995-96 was finally broken near the end of the second week of April when the mercury rose to 80°.

I remember snows well into April in Central Massachusetts and seeing snowflakes in early May 1996 

[donsutherland1]

2 minutes ago, White Gorilla said:

I remember snows well into April in Central Massachusetts and seeing snowflakes in early May 1996 

Parts of central New England saw some snow on May 6, 1996. I was dealing only with the larger area covered by the NYC subforum. 1995-96 was an amazing and long-lived winter.

[uncle W]

3 hours ago, donsutherland1 said:

Parts of central New England saw some snow on May 6, 1996. I was dealing only with the larger area covered by the NYC subforum. 1995-96 was an amazing and long-lived winter.

there was probably snow or snow on the ground for every holiday that winter...It snowed just after Thanksgiving...Flurries Christmas day with snow on the ground...leftover snow on the ground New Years day...snow on the ground on Martin Luther Kings day...snow on Groundhogs day...Vallintine's day...Easter...no fourth of July but you can't have everything...

[psv88]

-1.6 for the month here. Think we break even by months end

[Cfa]

-1.9 here (compared to ISP normals). ISP is currently -1.2.

I’ve been cooler than ISP for the past week for whatever reason, the rest of the month has been fairly identical between here and there.

[PB COLTS NECK NJ]

1 hour ago, psv88 said:

-1.6 for the month here. Think we break even by months end

At -1.6 prob .. Maybe you eek out N

 

Theses , no.

JFK - 3.5

LGA  - 3.2

NYC - 2 

[uncle W]

2017-18 verses the analogs...

winter.......Dec and Jan temp...ave...snowfall

1962-63...31.5.....30.1.....30.8.......9.8".....cold Feb...

1967-68...38.2.....26.7.....32.5.....12.3"....cold Feb...

1989-90...25.9.....41.4.....33.7.......7.9"....mild Feb...

1995-96...32.4.....30.5.....31.5.....40.5"....ave Feb...

2000-01...31.1.....33.6.....32.4.....21.7"....milder Feb...

2005-06...35.3.....40.9.....38.1.....11.7"....mild Feb...

2013-14...38.5.....28.6.....33.6.....28.3"....cold Feb...

2017-18 35.0....32.0....33.5.....17.9"....???

[psv88]

2 hours ago, Cfa said:

-1.9 here (compared to ISP normals). ISP is currently -1.2.

I’ve been cooler than ISP for the past week for whatever reason, the rest of the month has been fairly identical between here and there.

Yea I’ve noticed that too. I’ve been much cooler than islip lately. Shocked they are only -1.2

[WeatherFeen2000]

11 hours ago, bluewave said:

Looks like an MJO 7 gradient pattern setting up for early February with the battlezone between cold and warm close to the East Coast. Should feature  a back and forth between AN and BN days here. We'll probably need the MJO to head for phase 8-2 in order to finally pull the trough into the East for mid-February and beyond.

http://wx.graphics/

 

To me that looks like the snowy part no suppression but cold enough for snow pattern

[CIK62]

Remainder of Jan. is averaging 37degs., or 5degs. AN.

Month to date is -2.0 degrees.  Should end at -0.70 degrees.

The full 8 days are averaging 38degs., 5 or 6 degrees AN.

[donsutherland1]

Following a 6-day period during which the temperature averaged 41.9°, which is more typical of mid-March than late January, cooler air returned to the Northeast. Despite brilliant sunshine, the temperature rose no higher than the middle 30s in New York City and nearby areas and struggled just to reach freezing in its more distant northern suburbs yesterday.

After a somewhat colder than normal start this morning, the temperature will approach or reach 40° across much of the region. 50° readings appear to be in store for the upcoming weekend.

As the MJO moves into Phase 7 for the start of February, the probability of measurable snow will be close to the climatological norm for the first half of February. Had the PDO been negative, snowfall prospects would be below the climatological norm. Phases 8 and 1 would typically have a higher than climatological probability of measurable snow events. In terms of significant snowfall (6” or more) events, Phases 7, 8 and 1 account for 64% of such events in the February 1-15 period. For 10” or more snowfalls, Phases 7, 8, and 1 account for 78% of such events during the same period.

In short, the progression of the MJO through Phases 7, 8, and 1 during February suggests the potential for above normal snowfall. Further, there would be a heightened probability of a significant snowfall during the MJO’s progression through those phases.

New York City’s Average Temperature Through:

1/25: 30.3° (2.0° below normal; 1/25 estimate: 30.2°-30.5°)
1/31: 31.1°-32.1° (1/25 estimate: 31.0°-32.1°)

Per aggressive sensitivity analysis, the estimated probability of a below normal monthly anomaly: 73% (1/25 estimate: 62%)

[bluewave]

This is the first time since ISP regular records began in 1964 that they had 5 Januaries in a row with over 12". The well above normal snowfall was the one constant with variable monthly temperature departures.

January ISP:

2018..29.5...-1.0....16.0"....so far

2017..36.2..+5.6....14.0"

2016..33.3...+2.7....24.8"

2015..28.7....-1.9....30.2"

2014...27.7....-2.9...25.2"

 

[BxEngine]

The 64% of significant snowfall during phases 7 8 and 1 kinda surprised me @donsutherland1, fully expected that to be higher. I wonder if the SE ridge allowing some blockbuster storms even in the warmer phases has something to do with it? 

[SnowGoose69]

1 minute ago, BxEngine said:

The 64% of significant snowfall during phases 7 8 and 1 kinda surprised me @donsutherland1, fully expected that to be higher. I wonder if the SE ridge allowing some blockbuster storms even in the warmer phases has something to do with it? 

It may be that some MJO phases in significant ENSO events behave differently than they otherwise would.  So a snow event may be more likely in phase 4 and 5 in some situations than it normally is.  

[donsutherland1]

32 minutes ago, BxEngine said:

The 64% of significant snowfall during phases 7 8 and 1 kinda surprised me @donsutherland1, fully expected that to be higher. I wonder if the SE ridge allowing some blockbuster storms even in the warmer phases has something to do with it? 

A combination of factors may be likely. Sometimes the synoptic pattern is inconsistent with what one might expect with a given MJO phase. The sample only includes the period for which daily MJO values are available February 1975 afterward. Sample size issues may also be skewing the results somewhat. The SE ridge may also be at play in some cases.

[CPcantmeasuresnow]

Below is a chart of snowfalls 8 inches or greater in NYC since 1870 by 7 day period. As you can see the coastal areas like NYC are in their prime period for the next month. The 14 day period of February 2nd through the 15th is the prime time frame historically, with 28 storms in that 14 day period.

I specifically chose 8 inch storms in NYC because many times, if not the majority of times, our geographic area exceeds a foot of snow when central park is recording 8 inches or more.

Of course the time periods here extend out later in the season for big storms the further north and west you are from NYC.

 

[doncat]

Still with a -2.9° departure for the month.

[BxEngine]

Thanks Don bluewave and cp...you guys (and uncle as well as others) are invaluable with the stats and local knowledge.

[CIK62]

Last 5 days of the month averaging 39degs., or 6degs. AN. 

Month to date still  -2.0.   We should end Jan. @ -0.71.

The whole 8 days are averaging 37degs., or 4degs. AN.

[bluewave]

Looking like our 3rd Saturday in a row this January to reach 50 degrees or higher.

NYC....1/13.....53......1/20....52

 

[donsutherland1]

With 5 days remaining in January, the temperature would need to average approximately 11.8° above normal for January to finish at exactly normal in Central Park. That won’t happen. Instead, despite this weekend’s milder readings, January will likely finish nearly 1° below normal.

Some of the guidance has suggested the possibility of a small snow event January 29-30 period. Right now, it appears likely that most of the measurable snow will likely fall east of the NYC metro area unless parts of the region are affected by an inverted trough. Such troughs cannot be pinpointed with much precision this far out, so it’s too soon to have much confidence in the development of such a trough, much less its placement.

Seasonal snowfall amounts and anomalies through January 26 are:

Albany: 24.8” – 7.2”
Allentown: 15.0” +1.0”
Atlantic City: 24.2” +7.4”
Baltimore: 6.5” -2.3”
Bangor: 56.2” +23.2”
Binghamton: 26.6” -16.8”
Boston: 24.6” +3.4”
Bridgeport: 18.0” +5.7”
Buffalo: 59.8” +1.9”
Burlington: 41.7” +0.7”
Caribou: 76.6” +20.4”
Concord: 37.2” +4.8”
Harrisburg: 10.0” -2.8”
Hartford: 23.0” +3.3”
Islip: 22.0” +10.5”
New York City: 17.9” +7.1”
Newark: 17.1” +4.9” 
Philadelphia: 12.9” +4.1”
Pittsburgh: 27.2” +7.0”
Portland: 40.8” +9.3”
Providence: 22.7” +5.0”
Rochester: 63.0” +10.0”
Syracuse: 79.1” +8.0”
Washington, DC: 3.1” – 4.1”
Worcester: 34.5” +3.0”

Many of those locations that had seen below normal snowfall through January 26 will likely reach or exceed normal seasonal figures by the end of February. Those that are above normal could see even larger positive anomalies by the end of February.

More immediately, there has been a consistent signal on the guidance for the passage of a cold front possibly with a deepening storm moving up along that front during the February 2-3 period. The 0z ECMWF focused its heaviest snows east of the City into New England while the 0z GGEM showed a moderate to significant snowfall across much of the region. The differences among the guidance will need to be resolved, but the main point right now is that there may be an opportunity for accumulating snowfall during the first week of February.
 
New York City’s Average Temperature Through:

1/26: 30.4° (2.0° below normal)
1/31: 31.3°-32.1° (1/26 estimate: 31.1°-32.1°)

Per aggressive sensitivity analysis, the estimated probability of a below normal monthly anomaly: 74% (1/26 estimate: 73%)

[doncat]

Stayed clear and calm overnight so did manage to get down to 24°.

[uncle W]

29 minutes ago, doncat said:

Stayed clear and calm overnight so did manage to get down to 24°.

even where I was it was 28...Manhattan was at least 5 or ten degrees milder from the heat island...This is why record cold from the 1800's is hard to break...