Jump to content
  • Member Statistics

    17,501
    Total Members
    7,904
    Most Online
    ChicagoGuy
    Newest Member
    ChicagoGuy
    Joined

All-purpose Thunderstorm Discussion Thread II


CT Rain

Recommended Posts

45 minutes ago, CT Rain said:

NCAR ensembles remain bullish but most of the other hires stuff keeps things pretty quiet over SNE until 0z. That's definitely the concern today.

Is it entirely possible we could see a late evening show here (not talking about TOR potential) but storms/severe threat 

Link to comment
Share on other sites

  • Replies 243
  • Created
  • Last Reply
7 hours ago, Professional Lurker said:

Great time to be pitching a tent tomorrow in the catskills just outside of Hunter mtn.

...hope i don't end up killing my family.

Sent from my SM-G920P using Tapatalk
 

No joke.

Happened right by my place in the violent t-storm this weekend:  http://www.thedailystar.com/news/local_news/camper-dies-from-falling-tree-limb/article_508b7e08-d401-5542-a9d1-449940c30580.html

Link to comment
Share on other sites

Mets, think I should delay my trip to north/south lake for a day?

I've been there before, it's 2200 feet straight up off the floor of the hudson, tons of trees have lightning scars. (Of course, we'd shelter in our car if it got bad...) Would be tenting with my family.

My main concern is wind, as tents/tarps typically don't respond well to huge gusts.

Sent from my SM-G920P using Tapatalk



Link to comment
Share on other sites

need that warm front over NE PA to make it thru - 3 hours of obs not indicating it is in any hurry to move, and in fact, there is still slightly higher PP over Maine/GOM region than SW which means that makes it difficult to do so...  it's an evolving scenario though, so not ruling at that high slipping E and then the warm frontal having less inhibition to moving NE. 

if so - ... i like the general SW wind with DP spike with veered winds in the favored topographical regions - deeper layer mechanics do support some rotation above the deck, but the helicity in the lowest levels needs that direction assist.  

the other possibility is that more sun evolves mid day and then we can cook up some instability along and ahead of the warm boundary, when the helicity and SRH would be more contributory/positive.  so far sat vis loop is so-so

Link to comment
Share on other sites

Sipprell Gone Wild(SGW) in the new update:

*/ Highlights...

 * Strong to severe storms today
 * Heavy rain and damaging winds the main threat
 * Low risk of a tornado
 * Confidence greatest impacts over N/W portions of MA and CT
 * Impacts: downed tree, tree limbs, power lines, urban and poor
   drainage flooding

*/ Discussion...

Evaluating ensemble and probabilistic data while interpreting a
forecast consensus of mass fields. That seems to be the best way
to go today instead of evaluating individual QPF output.

Observationally, warm front held SW across NE PA into the NYC
tri-state metro and out across the S shoreline of New England
gradually pushing N. This as cloud breaks are allowing for the
build up of instability across the region though beneath decent
ridging throughout much of the atmospheric column and overall
anticyclonic flow. Sub-tropical moisture building into the region
with precipitable waters building up to 2 inches. Veering wind
profiles, most notably in the 0-1 km with a reaper appearance per
the 12z soundings out of Albany and Upton NY. But poor mid-level
lapse rates, and the boundary layer has still yet to mix out given
the dominant N flow prevailing and the warm front held up S/W.

To the forecast, first and foremost, have slowed timing somewhat
with the main window of activity developing around 2 to 4 pm
mostly over the W-half of the forecast region. But question
whether daytime mixing will speed it up more than originally
thought. Considering low to mid level height falls around this
time below H7 with some weak mid-level energy moving through the
weakening influence of anti-cyclonic flow (through prevailing at
H5 through roughly 10-11p per a consensus of forecast guidance),
going with the early afternoon timing of the warm front lifting
through and attendant strong to severe weather. This as the
atmosphere is primed as observed per the 12z sounding out of
Upton, though notably a bit less from Albany.

Still some question as to how far N the warm-front tracks and
whether cloud debris will be an issue. Also whether anticyclonic
flow will squash a good portion of the forecast area. With height
falls mainly to the W gives confidence towards a serious and
significant severe weather setup over N/W CT and MA inclusive of
the CT River Valley.

Re-iterating some points:

Rainfall...Expect precipitation efficiency given 12z soundings
highlighting freezing levels around H6 (14 kft agl). Ensemble
probabilistics suggest potential rainfall rates of 1-2 inches per
hour with outcomes over N/W MA and CT with WPC highlighting a
slight risk of excessive rainfall. What concerns me is whether
storms hinge along the lifting warm front over a particular
location. There is a low risk of flash flooding, but greater
confidence of urban, poor-drainage issues. Low confidence to
warrant a flood watch of any type.

Severe...as the warm front lifts N/E, will see dewpoints surge
into the 70s and with available sunshine and boundary-layer
destabilization, expect mean-layer CAPEs to build to roughly
1000-2000 j/kg in an environment of W/SW shear of 0-6 km around
30-40 kts, and of greater concern, continued 0-1 and 0-3 km
veering wind profile and low LCL`s. A SLIGHT risk has been posted
by SPC accordingly with 5% risk of tornadoes. As to storm-mode,
line-echo wave patterns developing along the warm front and within
the warm moist sector, but some concern we could see supercells
developing along the warm front as well given the veering wind
profile through the atmosphere and level of shear.

Have gone closely with NCAR ensembles. Have exhibited a good signal
of holding the warm front off and keeping the bulk of instability
confined to S/W New England. Most notably is mean 1 km reflectivity.
Quite impressive that the mean is capturing such a strong signal.
This in addition to strong sig-tor probs.

Have gone with the greatest risk of strong to severe storms across
the CT River Valley of MA and CT and points W of there. Prevailing
with gusty winds, frequent lightning, and heavy rain. Again, there
is the risk of tornadoes.
Link to comment
Share on other sites

29 minutes ago, Damage In Tolland said:

Sipprell Gone Wild(SGW) in the new update:


*/ Highlights...

 * Strong to severe storms today
 * Heavy rain and damaging winds the main threat
 * Low risk of a tornado
 * Confidence greatest impacts over N/W portions of MA and CT
 * Impacts: downed tree, tree limbs, power lines, urban and poor
   drainage flooding

*/ Discussion...

Evaluating ensemble and probabilistic data while interpreting a
forecast consensus of mass fields. That seems to be the best way
to go today instead of evaluating individual QPF output.

Observationally, warm front held SW across NE PA into the NYC
tri-state metro and out across the S shoreline of New England
gradually pushing N. This as cloud breaks are allowing for the
build up of instability across the region though beneath decent
ridging throughout much of the atmospheric column and overall
anticyclonic flow. Sub-tropical moisture building into the region
with precipitable waters building up to 2 inches. Veering wind
profiles, most notably in the 0-1 km with a reaper appearance per
the 12z soundings out of Albany and Upton NY. But poor mid-level
lapse rates, and the boundary layer has still yet to mix out given
the dominant N flow prevailing and the warm front held up S/W.

To the forecast, first and foremost, have slowed timing somewhat
with the main window of activity developing around 2 to 4 pm
mostly over the W-half of the forecast region. But question
whether daytime mixing will speed it up more than originally
thought. Considering low to mid level height falls around this
time below H7 with some weak mid-level energy moving through the
weakening influence of anti-cyclonic flow (through prevailing at
H5 through roughly 10-11p per a consensus of forecast guidance),
going with the early afternoon timing of the warm front lifting
through and attendant strong to severe weather. This as the
atmosphere is primed as observed per the 12z sounding out of
Upton, though notably a bit less from Albany.

Still some question as to how far N the warm-front tracks and
whether cloud debris will be an issue. Also whether anticyclonic
flow will squash a good portion of the forecast area. With height
falls mainly to the W gives confidence towards a serious and
significant severe weather setup over N/W CT and MA inclusive of
the CT River Valley.

Re-iterating some points:

Rainfall...Expect precipitation efficiency given 12z soundings
highlighting freezing levels around H6 (14 kft agl). Ensemble
probabilistics suggest potential rainfall rates of 1-2 inches per
hour with outcomes over N/W MA and CT with WPC highlighting a
slight risk of excessive rainfall. What concerns me is whether
storms hinge along the lifting warm front over a particular
location. There is a low risk of flash flooding, but greater
confidence of urban, poor-drainage issues. Low confidence to
warrant a flood watch of any type.

Severe...as the warm front lifts N/E, will see dewpoints surge
into the 70s and with available sunshine and boundary-layer
destabilization, expect mean-layer CAPEs to build to roughly
1000-2000 j/kg in an environment of W/SW shear of 0-6 km around
30-40 kts, and of greater concern, continued 0-1 and 0-3 km
veering wind profile and low LCL`s. A SLIGHT risk has been posted
by SPC accordingly with 5% risk of tornadoes. As to storm-mode,
line-echo wave patterns developing along the warm front and within
the warm moist sector, but some concern we could see supercells
developing along the warm front as well given the veering wind
profile through the atmosphere and level of shear.

Have gone closely with NCAR ensembles. Have exhibited a good signal
of holding the warm front off and keeping the bulk of instability
confined to S/W New England. Most 

Great AFD congrats Berks Litchfield county

Link to comment
Share on other sites

59 minutes ago, CoastalWx said:

Tough to ignore the dynamics tonight despite lack of QPF. 

Have to imagine winds may stay more locally backed, particularly in the CT River Valley vicinity. Interesting that the HRRR tries to pop a few cells overnight in an environment with sizable forecast hodographs.
HRRRNE_con_stp_014.png

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...