-
Hello, please take a minute to check out our awesome content, contributed by the wonderful members of our community. We hope you'll add your own thoughts and opinions by making a free account!
Severe New Years Severe Weather Event
- Thread starter Snowfan
- Start date
Cape and low level lapse rates would be higher than progged with the HRRR decoupling the boundary layer. It must have too much GFS in it.
Ron Burgundy
Member
Ruled it a tornado, didja? ? And yes, I fully respect NWS’s scientific process…
Both WRFs look to show about the same thermos as the HRRR, however show almost zero convection. You can’t pull soundings so I’m not sure if they are decoupling as well. If any cells can get going from 3-10pm or so across central and north AL, it will get really dangerous.
3km NAM has low level lapse rates 5.1-5.3C across central AL tomorrow evening.
Cad Wedge NC
Member
You are a GW troll. That is that is a fact. You have already been told that there is a thread for your babble, yet you still insert your GW jabs whenever you can.
BHS1975
Member
Enough! Don’t make us hit the timeout button please.
Z
Zander98al
Guest
Sounds too low, also the cams your talking about in the previous post. Are the ones that showed very strong updraft swaths that didn't do much, going to take those with a grain of salt lol
Will be a tough forecast for SPC and the various NWS. Looks like all or nothing.
Z
Zander98al
Guest
Think there taking the all route with how they've worded things.
Lostnthaweather85
Member
Idk the way I read them they sounded like the threat was conditional and they weren’t sold one way or another.
Z
Zander98al
Guest
I read the opposite tbh. At least for north and Central alabama
 |
|  | |
 |
| News | Search for: SPC NCEP All NOAA | 
|
|
|
@NWSSPC
Claycochaser
Member
From BMX
Severe Potential:
The threat for severe storms tonight into Sunday morning appears to
have several limiting factors. In the event that updrafts are strong
enough to take advantage of the abundant wind shear, damaging winds
and tornadoes could occur. This potential appears low at this
time, but mesoscale trends will need to be monitored. Based on
the reasons outlined below, the Enhanced Risk has been trimmed to
only cover the far northwestern portion of the forecast area.
Total removal of the Enhanced Risk was considered.
1. Height falls through the afternoon appear negligible as a strong
ridge holds firm over the Bahamas. Aside from passing showers and
perhaps a thunderstorm or two, relatively warm temperatures aloft
should prevent sustained robust updrafts through the afternoon.
Forecast soundings indicate warm temperatures aloft persisting
into the evening and overnight hours except for right along the
cold front. Updrafts may continue to sputter and struggle to
acquire strong mesocyclones.
2. With the lead shortwave merely sliding by to our north, large-
scale ascent over the warm sector will be minimized, reducing the
chance for pre-frontal storm development.
3. The lead shortwave will shear out across the Ohio Valley while
the main trough axis lags over the southern Plains, leading to
slow height falls during the evening and overnight hours. This
will support an elongated area of low pressure along the
approaching cold front instead of a well-defined surface low.
4. Mid-level flow will be nearly parallel to the cold front and the
potential QLCS along the front, limiting the potential for damaging
winds and mesovortices.
87/Grantham
Severe Potential:
The threat for severe storms tonight into Sunday morning appears to
have several limiting factors. In the event that updrafts are strong
enough to take advantage of the abundant wind shear, damaging winds
and tornadoes could occur. This potential appears low at this
time, but mesoscale trends will need to be monitored. Based on
the reasons outlined below, the Enhanced Risk has been trimmed to
only cover the far northwestern portion of the forecast area.
Total removal of the Enhanced Risk was considered.
1. Height falls through the afternoon appear negligible as a strong
ridge holds firm over the Bahamas. Aside from passing showers and
perhaps a thunderstorm or two, relatively warm temperatures aloft
should prevent sustained robust updrafts through the afternoon.
Forecast soundings indicate warm temperatures aloft persisting
into the evening and overnight hours except for right along the
cold front. Updrafts may continue to sputter and struggle to
acquire strong mesocyclones.
2. With the lead shortwave merely sliding by to our north, large-
scale ascent over the warm sector will be minimized, reducing the
chance for pre-frontal storm development.
3. The lead shortwave will shear out across the Ohio Valley while
the main trough axis lags over the southern Plains, leading to
slow height falls during the evening and overnight hours. This
will support an elongated area of low pressure along the
approaching cold front instead of a well-defined surface low.
4. Mid-level flow will be nearly parallel to the cold front and the
potential QLCS along the front, limiting the potential for damaging
winds and mesovortices.
87/Grantham
HSVweather
Member
Huntsville AFD
Despite the conditional threat during the afternoon, the forecast becomes much more concerning by the evening as the upper-trough and cold front approaches from the west. Very strong low-level winds and vertical wind shear will become established over the region as a LLJ
begins to nose into the area just ahead of the front. Resultant model soundings indicate large, looping hodographs, with 0-1 SRH values of 200-300 m2/s2. Surface dewpoints in the mid to upper 60s
will yield MLCAPE values of 500-1000 J/kg, more than sufficient for tornadic supercells in this very strongly-sheared environment. While the initial lack of forcing/weak height falls may discourage robust convection during earlier in the day, our feeling is that this will change by the evening and there will at least be a narrow window for
strong, discrete supercell development just ahead of the intense line of storms that will be moving in along the cold front. Should
this occur, these storms would pose a significant severe threat in the form of strong tornadoes. Timing of the most severe convection has slowed down slightly in these latest model runs. The latest guidance is focusing on a 23-01z timeframe for discrete storms to form ahead of the line that should be approaching northwest Alabama by 00-01z and sweeping east across the area during the 00-06z window from west to east. It should be noted that the storm mode along the line itself may end up being quite messy, but a strong tornado threat
will persist in any embedded supercell structures that can form. This tornado threat will also accompany a threat for strong damaging winds, hail, and heavy rainfall.
Despite the conditional threat during the afternoon, the forecast becomes much more concerning by the evening as the upper-trough and cold front approaches from the west. Very strong low-level winds and vertical wind shear will become established over the region as a LLJ
begins to nose into the area just ahead of the front. Resultant model soundings indicate large, looping hodographs, with 0-1 SRH values of 200-300 m2/s2. Surface dewpoints in the mid to upper 60s
will yield MLCAPE values of 500-1000 J/kg, more than sufficient for tornadic supercells in this very strongly-sheared environment. While the initial lack of forcing/weak height falls may discourage robust convection during earlier in the day, our feeling is that this will change by the evening and there will at least be a narrow window for
strong, discrete supercell development just ahead of the intense line of storms that will be moving in along the cold front. Should
this occur, these storms would pose a significant severe threat in the form of strong tornadoes. Timing of the most severe convection has slowed down slightly in these latest model runs. The latest guidance is focusing on a 23-01z timeframe for discrete storms to form ahead of the line that should be approaching northwest Alabama by 00-01z and sweeping east across the area during the 00-06z window from west to east. It should be noted that the storm mode along the line itself may end up being quite messy, but a strong tornado threat
will persist in any embedded supercell structures that can form. This tornado threat will also accompany a threat for strong damaging winds, hail, and heavy rainfall.
TileDude
Member
Interesting BMX scaled back their enhanced risk area to include only the northwest counties.
HSVweather
Member
This is the latest HRRR 10z, if any discrete cells form like shown from golden triangle to Huntsville around 1400-1600, those are the most concerning.
HSVweather
Member
1500 forecasted sounding from Morgan county ahead of those projected cells on the 10Z HRRR
Z
Zander98al
Guest
Those weather balloon soundings are going to be critical This afternoon