Week of June 10th Heavy Rain and Thunderstorms Discussion

[nzucker]

Extremely heavy rain right now...

[SnoSki14]

Yes, im really worried about this setup (and i love storms)

I'd rather take a couple more inches of rain and cool weather than the possibility of tornadoes although could things really end up that serious.

Tornadoes around here are hard to come by and are very weak or brief if they do appear.

[Guest Pamela]

Very heavy rain, some thunder in Port Jefferson @ 1:05 AM.  Adjacent Mt Sinai station showing 1.29" of rain in the last 24 hours.  June rainfall now 7.13".  Temp. 62.1 F.     

[bluewave]

In addition to the heavy rain threat, there could be tornadoes  right along the warm front

which the Euro and NAM bring across southern to central New Jersey.

 

 

 

 

[IsentropicLift]

Boy, if we were ever going to get a tornado outbreak up this way, that's pretty darn close to the ideal setup.

[bluewave]

Boy, if we were ever going to get a tornado outbreak up this way, that's pretty darn close to the ideal setup.

 

It's possible that the MA could get a later upgrade to MDT Risk when you see 30% for wind showing up in a day 3 outlook.

 

[IsentropicLift]

It's possible that the MA could get a later upgrade to MDT Risk when you see 30% for wind showing up in a day 3 outlook.

day3prob_0730.gif

That shows you they are expecting the low to track to our south which would limit severe potential but increase the flooding threat.

[bluewave]

That shows you they are expecting the low to track to our south which would limit severe potential but increase the flooding threat.

 

Yeah, the Euro is tracking the low south of the area along with the NAM. I can't remember the last time that

I saw a sub 1000 mb low track to our south in June with such a strong severe signal over the MA and a 

heavy rain threat across our area. This looks like one of those rare set ups that we haven't really seen

too often in the past. You don't usually see this type of jet coupling during June here with the exit

and entrance regions. Two jet streaks diving SE over the MW and GL with a small one off the MA and

another across NE.

 

[weathermedic]

Finished with another 2.0 inches of rain yesterday/last night.

[IsentropicLift]

The 00z GGEM tracks the low so far to our south that the northern edge of the precip just clips the area

 

 

The 06z NAM misses us to the south with the MCS for Thursday but tracks precip from the low over us

 

[Sundog]

 

The 06z NAM misses us to the south with the MCS for Thursday but tracks precip from the low over us.

 

The regular 6z NAM looks very different from the hi res version.

 

http://mag.ncep.noaa.gov/Image.php?model=nam&area=namer&param=sim_radar&cycle=06ℑ=nam%2F06%2Fnam_namer_054_sim_radar.gif

 

 

 

BTW I can't post gif files? That's what the board said when I linked the image to show up as opposed to the link that I have now.

[IsentropicLift]

The regular 6z NAM looks very different from the hi res version.

 

http://mag.ncep.noaa.gov/Image.php?model=nam&area=namer&param=sim_radar&cycle=06ℑ=nam%2F06%2Fnam_namer_054_sim_radar.gif

 

 

 

BTW I can't post gif files? That's what the board said when I linked the image to show up as opposed to the link that I have now.

Yes it does, that's why the normal version gives us almost 3.5" of rain and the high res is much less.

[IsentropicLift]

Judging by current radar, that band of rain should be here by 2-3PM. We have about 1000 J/KG of SBCAPE to work with but no shear.

[IsentropicLift]

The 12z NAM brings most of the area 0.25"+ or rain today. Judging by current radar, I would say that's about right.

 

[IsentropicLift]

Boy this run of the 12z NAM is going to slam us. Heavy rain moving into the area with an already sub 1000mb low over eastern OH at hr 48.

 

12z NAM is 2.0" + for most of us. Keeps the core of the heaviest rain just to our north

 

[IsentropicLift]

The high res NAM is more of a severe threat for us, although it completely got rid of the Mid-Atlantic MCS this run so I don't know if it can be trusted.

[IsentropicLift]

Then the second round

 

[TWCCraig]

Wow, just some epic frontogenesis on the NAM, not only a heavy rain threat, but also a wind threat too. Very rare 994 lows in June unless they are of tropical origins.

 

[IsentropicLift]

Wow, just some epic frontogenesis on the NAM, not only a heavy rain threat, but also a wind threat too. Very rare 994 lows in June unless they are of tropical origins.

 

The regular NAM and the 4K high res have been running very differently for the past day

[Brian5671]

wow at the above models...could be looking at another 2-4 inches of rain Thurs...

[bluewave]

Localized strong storms possible this afternoon as the shear and instability increase.

The steeper low level lapse rates could support downbursts with winds over 35-40

mph. Maybe a few special marine warnings possible later on.

 

 

[IsentropicLift]

I worry that the NAM, especially the 4k NAM is displacing the stratiform rain to far to the northwest of the center. The simulated radar looks like we're having a cold front passage with the low over NY State when in fact the low will be to the south of Long Island.

[Weathergun]

9z SREF is really bullish derecho and tornado probablities between the Ohio Valley and Mid-Atlantic tomorrow. Could go mod risk:

 

 

[earthlight]

Here's a discussion written for the website this morning about the storm potential on Thursday:

 

http://www.nymetroweather.com/2013/06/11/severe-storms-likely-for-the-mid-atlantic-on-thursday-how-far-north-will-they-go/

 

Also the hires 12z NAM has a great visualization of the warm front with the 10m winds. Wonder if we could see some rotating storms along the front as the sfc low moves nearby Thursday afternoon despite the main instability staying to our south. 

 

http://www.meteo.psu.edu/~fxg1/NAMSFC4_12z/wind54.gif

[Weathergun]

Here's a discussion written for the website this morning about the storm potential on Thursday:

 

http://www.nymetroweather.com/2013/06/11/severe-storms-likely-for-the-mid-atlantic-on-thursday-how-far-north-will-they-go/

 

Also the hires 12z NAM has a great visualization of the warm front with the 10m winds. Wonder if we could see some rotating storms along the front as the sfc low moves nearby Thursday afternoon despite the main instability staying to our south. 

 

http://www.meteo.psu.edu/~fxg1/NAMSFC4_12z/wind54.gif

 

12z NAM hodographs are ridiculous insane over LGA Thursday. But there is virtually no CAPE, for tornadoes:

 

 

[bluewave]

Here's a discussion written for the website this morning about the storm potential on Thursday:

 

http://www.nymetroweather.com/2013/06/11/severe-storms-likely-for-the-mid-atlantic-on-thursday-how-far-north-will-they-go/

 

Also the hires 12z NAM has a great visualization of the warm front with the 10m winds. Wonder if we could see some rotating storms along the front as the sfc low moves nearby Thursday afternoon despite the main instability staying to our south. 

 

http://www.meteo.psu.edu/~fxg1/NAMSFC4_12z/wind54.gif

 

Yeah, it looks like a tornado risk near the warm frontal location roughly over CNJ on Thursday.

We may see a MDT risk upgrade for portions of the MA. I was commenting that I can't

remember this strong of a low with a combination of severe south of the track and heavy

overruning rains passing  just south of our area in June. The upper jet is really

impressive coupled multiple exit and jet entrance regions. Any deviation north in

later runs would have to be monitored for a further north severe threat.

 

[earthlight]

12z NAM hodographs are ridiculous insane over LGA Thursday. But there is virtually no CAPE, for tornadoes:

 

Given the proximity of the warm front and instability, I have to admit I actually laughed out loud when glancing at bufkit and seeing that the CAPE was actually zero. 

[earthlight]

Yeah, it looks like a tornado risk near the warm frontal location roughly over CNJ on Thursday.

We may see a MDT risk upgrade for portions of the MA. I was commenting that I can't

remember this strong of a low with a combination of severe south of the track and heavy

overruning rains  in June passing  just south of our area in June. The upper jet

is really impressive coupled multiple exit and jet entrance regions. Any deviation north in

later runs would have to be monitored for a further north severe threat.

 

Agreed. The one thing I will say to look out for, as I spoke with forky about this morning, is the potential for the kinematics to outrun not only the best instability but also the best forcing. We saw a less extreme situation last year with a surface low passing over upstate new york. The best wind shear only slightly outran the forcing and the entire threat was disjointed. There were some slight hints of this on some models this morning..but in general I think I agree that in the end this will at least border on a moderate risk event. 

 

The warm front provides interesting potential for tornadoes and the wind threat could extend south of there through the DC area and Mid Atlantic states. For us it looks like a heavy rain event with some rumbles of thunder. 

[Dsnowx53]

Yeah, it looks like a tornado risk near the warm frontal location roughly over CNJ on Thursday.

We may see a MDT risk upgrade for portions of the MA. I was commenting that I can't

remember this strong of a low with a combination of severe south of the track and heavy

overruning rains in June passing just south of our area in June. The upper jet

is really impressive coupled multiple exit and jet entrance regions. Any deviation north in

later runs would have to be monitored for a further north severe threat.

Agreed. The one thing I will say to look out for, as I spoke with forky about this morning, is the potential for the kinematics to outrun not only the best instability but also the best forcing. We saw a less extreme situation last year with a surface low passing over upstate new york. The best wind shear only slightly outran the forcing and the entire threat was disjointed. There were some slight hints of this on some models this morning..but in general I think I agree that in the end this will at least border on a moderate risk event.

The warm front provides interesting potential for tornadoes and the wind threat could extend south of there through the DC area and Mid Atlantic states. For us it looks like a heavy rain event with some rumbles of thunder.

Definitely agreed. If our ML Lapse rates were better, the storms outrunning the best forcing wouldn't be as much of an issue, since updrafts would cold pool and sustain themselves. But alas, this is not the Plains...we don't get dry lines and we don't often get EML advection.

I think C NJ might be a tad too far north for the best tornado threat...I would favor S NJ and SE PA. The mode might not be discrete anymore by the time C NJ truly destabilizes and gets in on the lift.

[Dsnowx53]

Yeah, it looks like a tornado risk near the warm frontal location roughly over CNJ on Thursday.

We may see a MDT risk upgrade for portions of the MA. I was commenting that I can't

remember this strong of a low with a combination of severe south of the track and heavy

overruning rains in June passing just south of our area in June. The upper jet

is really impressive coupled multiple exit and jet entrance regions. Any deviation north in

later runs would have to be monitored for a further north severe threat.

Agreed. The one thing I will say to look out for, as I spoke with forky about this morning, is the potential for the kinematics to outrun not only the best instability but also the best forcing. We saw a less extreme situation last year with a surface low passing over upstate new york. The best wind shear only slightly outran the forcing and the entire threat was disjointed. There were some slight hints of this on some models this morning..but in general I think I agree that in the end this will at least border on a moderate risk event.

The warm front provides interesting potential for tornadoes and the wind threat could extend south of there through the DC area and Mid Atlantic states. For us it looks like a heavy rain event with some rumbles of thunder.

Another thing. Although I agree with the premise, I think forcing will definitely be more readily available this time around as well. Last year, the forcing was lifting up and out towards Canada -- this setup has a more rapid due west to east propagation of a further south surface low, so the best forcing will not necessarily be shoved northward; but rather, eastward, and could keep up with the storms.

I actually think there's a good chance that the cold front could merge with the discrete cells too quickly and force everything to be linear. However, there should be a few hour window where the mode will be discrete before the cold front's advancement -- that's when we'll have to watch out for tornadoes.