September 2025 OBS-Discussion centered NYC subforum

[psv88]

Water levels are high on the north shore. Probably a 1.5 feet above normal. Stiff breeze as well 

[wdrag]

2 hours ago, FPizz said:

Sundays forecast seems subject to change if Walt is correct with more rain.

I'll need to wait this out...  one thing I didnt see was EC AI was almost nothing.

It could be the EC suite (non AI) is too strong and too far southwest with the 5H vort plunging sdwd from south center Canada with the resultant sfc response too robust here. Would make this a period of waa showers Sunday afternoon and maybe cool frontal showers Monday.

I do think its best to play temps conservatively and cooler in this pattern for another 10 days and wait this out a bit but I plan on showers Sunday afternoon and possibly right into Monday night.  

Patience... at least for me til a I reconsider later on.  12z WPC D4-6 guidance has boosted qpf a bit and I think that right... dont plunge into the unusual heavy solution till we have more confidence. Lets not say its a nice end to the weekend beginning of next week. 

[Brian5671]

Euro wet for next Monday

[FPizz]

5 minutes ago, Brian5671 said:

Euro wet for next Monday

CMC wet east of NYC, drier west, but other models have nothing

[Brian5671]

3 minutes ago, FPizz said:

CMC wet east of NYC, drier west, but other models have nothing

Cutoff lows notoriously difficult with precip placement.  But would be nice to get another dump of rain and on a Monday-that would be great

[jm1220]

1 hour ago, FPizz said:

CMC wet east of NYC, drier west, but other models have nothing

If the low can close off and dig west of us, we’ll get a moist fetch off the ocean. If not, probably cloudy and nasty. 

[Stormlover74]

10 minutes ago, jm1220 said:

If the low can close off and dig west of us, we’ll get a moist fetch off the ocean. If not, probably cloudy and nasty. 

euro did this last month and busted badly. could still happen but right now if its alone its probably off

[donsutherland1]

Today, Islip recorded its third consecutive high of 74° and Central Park saw its third consecutive high of 73°. The last time both locations had three consecutive days with the same high simultaneously was during July 6-8, 2000 when both locations had three consecutive highs of 79°.

Tomorrow will be briefly warmer with highs in the upper 70s to perhaps lower 80s. A few locations could see a shower or thundershower tomorrow night into Friday as a cold front pushes through.

The next round of showers or rainfall could be Monday.

September 1-15 is on track to achieve a solid cool anomaly. Since 2000, there have been nine years that saw a cooler than normal first half of September. Two-thirds of those years went on to record a warmer than normal second half of September. Only two of those years (2017 and 2019) wound up with a monthly mean temperature of 70.0° or above. Overall, for two-thirds of those years, the cool start was sufficiently cool to produce a cooler than normal monthly anomaly. The last year that saw both a cooler than normal first half and second half of September was 2009. Prior to that, it was 2001. The last year to record a cooler than normal first half of September followed by a warmer than normal September was 2024.

The ENSO Region 1+2 anomaly was -0.3°C and the Region 3.4 anomaly was -0.4°C for the week centered around August 27. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.33°C and the ENSO Region 3.4 anomaly has averaged -0.32°C. La Niña conditions will likely develop during mid- or late-autumn.

The SOI was -5.70 today. 

The preliminary Arctic Oscillation (AO) was +0.415 today. 

Based on sensitivity analysis applied to the latest guidance, there is an implied near 59% probability that New York City will have a cooler than normal September (1991-2020 normal). September will likely finish with a mean temperature near 68.4° (0.8° below normal). 

Supplemental Information: The projected mean would be 0.4° above the 1981-2010 normal monthly value.