Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

Feb 24-25th Severe Weather


Anti tornado

Recommended Posts

33 minutes ago, andyhb said:

Thanks for the input.

VBV, cap, questionable prefrontal trough, etc...

 

from a strictly tornado potential perspective, the threat is low. I think they maintain the enhanced for hail and wind and that's it. 

 

Tornado: 5%

hail: 30%

wind: 30%

Link to comment
Share on other sites

  • Replies 291
  • Created
  • Last Reply
3 minutes ago, Anti tornado said:

VBV, cap, questionable prefrontal trough, etc...

from a strictly tornado potential perspective, the threat is low. I think they maintain the enhanced for hail and wind and that's it. 

The enhanced was never for tornadoes in the first place...

Link to comment
Share on other sites

1 hour ago, Anti tornado said:

 

I realize that. Just people (myself included) in this thread seemed to be hyping tornado threat. 

 

1 hour ago, Anti tornado said:

Coming from a guy who, 90% of the time, post 0 analysis. Lol

 

1 hour ago, Anti tornado said:

I've been on this board for less than 2 weeks. I will post more in depth as situations warrant it

I would cool it if I were you, coming in here guns ablazing isn't going to go over well at all.

Link to comment
Share on other sites

30 minutes ago, Sidewinder said:

The warning in Cass IA is really something. Not too often you see surface temp of 34 and svr hail. 

A few years back there was an anafrontal event in the plains and parts of Nebraska were getting hail with temps in the 20s, one of the strangest events I have ever seen.

Link to comment
Share on other sites

Excellent discussion by DTX this morning, pretty much highlights everything for this afternoon.

Departure of the morning convection will precede the arrival of the
surface low and warm front early enough to not impact model
depictions of the surface features too much. Surface pressure falls
ahead of the low and along the warm front appear reasonable given
strong difluent southwest flow aloft up against the cold Great Lakes
aggregate. This will no doubt affect the precise effective position
of the warm front that afternoon surface observational trends will
help to pin down but remains in the neighborhood of model depictions.
The other larger scale features driving severe weather potential are
also being clarified by upstream observational trends. Upstream 00Z
soundings and hourly mesoanalysis indicate the broad and strong EML
that is projected to move northward with the system during the day
punctuated by lapse rates in the 700-500 mb layer near 9.0 C/km.
Surface observations in the mid to upper 50s are also shown in the
warm sector of the system that will be carried northward into the
Great Lakes by evening. This is expected to result in more than
adequate instability for thunderstorms in such a strongly forced
synoptic environment. A surface parcel of 65/58 will be capable of
0-1km MLCAPE approaching 1000 J/kg, enough to produce convection
potent enough to withstand and be organized by the strong wind
profile within the warm sector and along the cold front. Assuming
initiation is after 21Z, then it will be close enough for discrete
cell organization to move into SE Michigan by early evening. Updrafts
will have a chance to be enhanced by rotation which will make large
hail a concern due to freezing level only around 10000 ft along with
tornadogenesis in strong right-movers in the warm sector or along the
warm front. Initiation time is currently the main source of
uncertainty. There are some mesoscale model solutions clustering
around earlier timing in prefrontal fashion followed by a second
round of storms along the cold front that would be more prone to
linear modes and damaging straight line wind. The tendency for the
warm sector to remain capped under the EML favors a lean toward later
initiation while keeping in mind the former is a plausible scenario.
Link to comment
Share on other sites

DTX update...

000
FXUS63 KDTX 241559
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1059 AM EST Fri Feb 24 2017

.UPDATE...

Early day forecast update mainly to provide some additional temporal
detail in terms of fog/stratus reduction, thermal trends and
eventual emergence of a solid non-convective uptick in wind gusts as
the warm sector surges in.

FYI...DTX will be doing a special 21z RAOB

Well-defined warm frontal boundary now arcing from near
Kalamazoo/Battle Creak to just north of Toledo. Solid wing of
elevated convection anchored within a zone of 700-850 mb ascent now
racing through the north half of the forecast area, should clear the
thumb by 18z.  Attention then shifts to both the thermodynamic and
kinematic adjustment as the warm front begins to surge steadily
north/northeast through the afternoon period. Warm sector
immediately upstream defined by mid 50s dewpoints, with a
corresponding increase in mixed layer depth translating into gusts
into the 30 knot range.  This well defined elevated mixed layer
arriving coincident with the overall advective process, establishing
a solid cap for the early-mid afternoon period locally.  During this
time, combination of daytime heating and warm/moist advection will
at least establish a modestly unstable low level environment
/MLCAPE approaching 1000 J/KG/. Convective potential remains the
most tenuous to define between roughly 21z and 01z. Lead pre-
frontal trough or slightly elevated frontal boundary to accelerate
eastward out ahead of the primary cold frontal zone during this time.
Weak returns now noted emerging across far eastern IL/west-central
IL evidence of this ascent and the sizable increase in mid level
lapse rates. Outstanding question locally remains too what degree
does this ascent help overcome and/or weaken the existing cap.
Within a background of tremendous deep layer and low level shear
parameters /particularly along the warm frontal interface/...
potential is there for a quickly evolving lower coverage of
discreet/supercellular structures. With that said, capped warm
sector environment may prove an adequate limiting factor, effectively
stunting greater cell growth/organization until the front sweeps
through 01z-05z. Extremely conditional environment, one that latest
hi res guidance continues to struggle in handling.
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...