July 2018 Discussions & Observations Thread

[NycStormChaser]

5 minutes ago, Rtd208 said:

Showers and thunderstorms will be possible over the next couple of days especially on Friday when we have the potential for some severe weather. Then it looks like we will get a brief break with more heavy rain/storms possible next week.

Yeah. Friday has potential to be a good day for severe weather atleast on east coast standards. 

[Eduardo]

Just missing the action here in Lindenhurst (SW Suffolk) as most of the precip has been to my west thus far.  Looks like that next batch about to come onshore will miss me as well, but to the east.  Have had some brief showers here this evening, but overall have been pretty dry.  Pretty much a non-event thus far for me.

[LongBeachSurfFreak]

Getting close to 2” in the last 2 hours at the Wantagh meso. 

[snywx]

3 hours ago, Juliancolton said:

I'm just barely over an inch total for this whole ordeal since the first LP wave on Sunday morning. Days and days of drizzle punctuated by occasional showers.

Crazy..

4.45" for the event here

[Rtd208]

SPC Day 2 Outlook

https://www.spc.noaa.gov/products/outlook/day2otlk.html

 

[CIK62]

Remainder of July averaging 79degs., or 2degs. AN.

Month to date is  +1.5.   Should end July at  +1.6.   The full 8 days are 80/+3.

Our three main models are barely normal now for the next 10 days at 1"-2".  [1.4" is Normal]

[bluewave]

2.41" at Wantagh. Good to see the Euro consistent for several days with the LI Wed night heavy rain forecast. So we are two weeks in a row with a heavy rain event. Last week was over 1" in just 30 minutes. Very high PWAT/dew point regime for our area.

[tim]

3 minutes ago, bluewave said:

2.41" at Wantagh. Good to see the Euro consistent for several runs with the LI Wed night heavy rain forecast. So we are two weeks in a row with a heavy rain event.

..getting nickled and dimed out here...got .50 from last nites rain.

[bluewave]

12 minutes ago, tim said:

..getting nickled and dimed out here...got .50 from last nites rain.

Yeah, the orientation of the WAR and persistent SE flow has favored areas further west for the heaviest rains this month to date.

July rainfall so far

ISP.....2.95

NYC....6.80

BWI... 15.43

[Cfa]

0.61” with this event, the bulk of it falling towards the end (got lucky).

3.53” for the month so far. Pretty huge turnaround from having only 0.12” during the first half.

[Brian5671]

Wet pattern for most of the East Coast next few weeks

[psv88]

0.61 overnight, brings 24 (really 12 hour) hour total to 1.54”. Over 3” now in the last week

[SACRUS]

TOday looks to be much like Tue.  Skies should get long breaks of sun (Florida-style).

 

 

[SACRUS]

Still looks like we see hints the W. ATl Ridge (WAR) builds west the first week of Aug (8/3) for a period allowing a break of the persistent southerly / wet tropical flow to a more SW flow and hotter temps.  Until then Miami style weather continues.  

[LongBeachSurfFreak]

2 hours ago, bluewave said:

Yeah, the orientation of the WAR and persistent SE flow has favored areas further west for the heaviest rains this month to date.

July rainfall so far

ISP.....2.95

NYC....6.80

BWI... 15.43

Over 6” here in Wantagh just about 10 miles west of Islip. I have really lucked out this month getting allot of Nassau county specials. Things are very lush here now!

[psv88]

26 minutes ago, LongBeachSurfFreak said:

Over 6” here in Wantagh just about 10 miles west of Islip. I have really lucked out this month getting allot of Nassau county specials. Things are very lush here now!

5" here this month, right in between...

[bluewave]

3 hours ago, LongBeachSurfFreak said:

Over 6” here in Wantagh just about 10 miles west of Islip. I have really lucked out this month getting allot of Nassau county specials. Things are very lush here now!

My weather highlight this month was picking up 1.30 in 30 minutes last week.  That is my heaviest 30 minute rainfall total of the last few years. But you  have me beat since 2015 with  the Wantagh deluge in September 2015 of 6+ in a few hours.  I haven't experienced really extreme rainfall  since the 10+ in under 12 hours in LB in August 2011.

[CIK62]

82degs here., with streaks of blue sky mixed in with the varied clouds.    Humidity must be 70% and felt worse with the sun hitting me while walking.

The best weather now appears to be Sunday into late Monday, then a lather, rinse, repeat cycle.     The period of lower PW and positive LI shifted from earlier runs which showed Friday PM to Sunday PM as OK.

The EURO is under +3 for the next 10, while the psycho GFS is +9.

[Juliancolton]

12 hours ago, snywx said:

Crazy..

4.45" for the event here

Yeah, the E-W gradient is insane. Reminiscent of last winter. I did a short waterfall tour in the Catskills this morning and was amazed at how high water levels were... it's pretty rare to get such high flow surrounded by the greens of summer, so that made for nice photos. Plattekill and Kaaterskill in particular were the angriest I've seen them in a long time. I'm sort of glad that the tropical Atlantic is as dead as it is - with the wet pattern liable to continue/resume into the beginning of August, even a more mellow Irene/Lee redux would be catastrophic.

[Brian5671]

39 minutes ago, Juliancolton said:

Yeah, the E-W gradient is insane. Reminiscent of last winter. I did a short waterfall tour in the Catskills this morning and was amazed at how high water levels were... it's pretty rare to get such high flow surrounded by the greens of summer, so that made for nice photos. Plattekill and Kaaterskill in particular were the angriest I've seen them in a long time. I'm sort of glad that the tropical Atlantic is as dead as it is - with the wet pattern liable to continue/resume into the beginning of August, even a more mellow Irene/Lee redux would be catastrophic.

quite true....

[Maureen]

15 hours ago, Rtd208 said:

Showers and thunderstorms will be possible over the next couple of days especially on Friday when we have the potential for some severe weather. Then it looks like we will get a brief break with more heavy rain/storms possible next week.

Is there ANY sign of a break from this wretched humidity any time soon-ish?

[psv88]

19 minutes ago, Maureen said:

Is there ANY sign of a break from this wretched humidity any time soon-ish?

Yes, September. We are in the dog days of summer. By September or October we usually start to cool off

[dWave]

Got everything going on now.

Partly sunny with rain 86 dew 72

[Cfa]

82/74 and sunny with a nice breeze. Big improvement over this morning.

[Rtd208]

Current temp 90/DP 72/RH 52%

[SACRUS]

Made it to 88 today.  Tue / Thu were not bad in what could have otherwise been a wash out of a week.  Weekend looking mostly good.

 

Lets see if the W.A.R trends more west for the 8/2 - 8/8 timeframe.  A little dent in the west coast ridge also could allow east coast heights to rise furthrr inland and push flow more SW 

 

[SACRUS]

7-26

ACY: 90
TEB: 90
LGA: 89
EWR: 88
New Brunswick: 87
TTN: 87
PHL: 87
NYC: 85
ISP: 83
JFK: 81

[Rtd208]

Current temp 77/DP 70/RH 74%

High for the day was 91

Picked up 0.09" of rain for the day.

6 day total rainfall 2.07"

[OHweather]

The severe threat for Friday afternoon/evening is certainly interesting, though it's likely that a modest onshore component to the low-level wind and somewhat later timing causes a lower threat near the coast, particularly south of NYC...

There will probably be some high clouds overspreading the region during the morning, but a period of decent heating looks likely.  Though not as moist as earlier in the week, there's still respectable low-level moisture in the lowest several thousand feet...which should allow dew points to stay in the upper 60s on Friday even with strong daytime heating causing good mixing.  Poor mid-level lapse rates will limit how unstable it will get to an extent, though with rich-enough low-level moisture and strong heating the potential will exist for 1500-2500 J/KG of MLCAPE to develop by the afternoon...which is plenty. 

A mid to upper jet will move overhead during the afternoon, increasing bulk shear.  Effective bulk shear of 30-40kt is expected to be in place Friday afternoon and evening.  This is plenty of speed shear.  The low-level flow is on the weaker side, which will probably keep the tornado threat fairly low despite good turning of the winds with height...though, any storms with a more deviate motion (right turners) could locally increase their storm-relative helicity (SRH) some...and locally increased wind fields near storms may also do that.  Given the deep-layer shear will be decently strong and the low-levels look to have good turning, I don't want to say something weird that results in a tornado is impossible, but the weak low-level flow should keep the threat fairly low.

For when/where storms fire and the mode of the storms...a weak boundary remains just inland from the coast right now, and the WPC and some models appear to keep that in place...perhaps getting re-enforced by a sea breeze by early to mid-afternoon.  The airmass really isn't capped, so once we get good heating by early afternoon convective temps will be reached.  Broad large-scale ascent overspreads the region by early afternoon as we get under the right-entrance quadrant of the jet stream to our north.  There also appears to be an area of modest vorticity over the Ohio Valley right now that would glance the region early to mid-afternoon.  Given this, suspect isolated to widely scattered storms fire early to at the absolute latest the middle of the afternoon.  Likely initially focused on that lingering boundary, perhaps just inland from the coast in NJ to just north of NYC.  Suspect due to the lack of a cap, the fairly sharp nature of the front, and broad large-scale ascent that the storms along the front will organize into a line over eastern PA and move east on the quicker side of modeling during the late afternoon or early evening...perhaps reaching NYC by 7-9PM.  Due to some potential overturning from pre-frontal convection and a weak onshore flow and starting to lose daytime heating, the frontal storms will probably start to weaken at some point as they move east across NJ/southern NY during the early evening.

Given moderate CAPE and deep-layer shear, the initial cellular activity may have some supercellular characteristics.  Again, suspect most won't tighten up enough to produce a tornado, but can imagine a scenario where it happens with one storm or something.  Main concern would be a hail risk and damaging downburst winds with any cells during the afternoon.  The amount of instability could be enough for some larger than normal hail...supported by Craven-Brooks numbers perhaps pushing 30,000-40,000...though, with weak mid-level lapse rates and warm/humid low-levels, both negatives for very large hail, am not positive on that threat.  Suspect any initial cells would have a hail threat, but that it may struggle to exceed quarter-sized.  If a cell or two really went to town, could see larger with them for a time.  Moderate DCAPE of 700-1000 J/KG due to some mid-level dry air would also support damaging downburst winds with stronger cells.  The line that I think will move in from the west could have a decent damaging wind risk, though again, suspect that'll start to peter out gradually as it moves east during the early evening, so not sure how much of that threat would make it to the coast, especially south of NYC. 

Would personally go 30% wind/15% hail/2% tornado risks, highest from the Hudson Valley (perhaps extreme western MA) down through eastern PA/western NJ, dropping off to a slight risk down towards DC due to somewhat weaker shear/forcing farther south...and also dropping off to the east towards the NJ coast as mentioned. 

[Rtd208]

SPC Day 1 Outlook

https://www.spc.noaa.gov/products/outlook/day1otlk.html