31 Bravo leads the way HOOAH!
Rank: F5 Superstorm
22 years old
Joined: 10-February 10
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Last Seen: 26th January 2013 - 04:04 AM
Local Time: Dec 8 2013, 09:16 AM
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27 Feb 2012
Went ahead and made this thread to keep this system's discussion out of the other thread. Felt like the 0Z guidance yesterday evening and night did a good job in coming to a generally good consensus with evolution and track of short waves, and SFC cyclogenesis. However, SPC keeps their predictability too low text. I feel there is enough confidence that there will be system move through the mid section of the country, bringing at least some kind of threat for severe weather across the Deep South to Southeast later this week...Models are showing a strong SFC cyclogenesis over Kansas rapidly deepening as it tracks towards the GL region...Out ahead of the system we have WSW winds aloft in the mid-levels which supports an EML moving over the large warm sector this should limit any premature convection until the CAP can break during peak heating hours, once then instability won't be seen as a problem with 60+ Tds all the way into the Ohio Valley region, and models already painting 1000+ J/KG CAPE Values across Deep South/Dixie alley with LI in the -4 to -7 range. With strong LLJ in 50-60KT range coming from the SSW with near 90 degree turn at 500MB as winds come out of the WSW, are yielding some long clockwise hodograph signatures. So as of right now all modes of severe weather look possible with this system...With that said, this is still 4-6 days out, and there is time for such a significant severe weather event to not materialize as some models have been painting the past few days now, although at the very least a marginal severe weather event is looking likely now. Still not liking the trends on the models, the 12Z Euro is rather very ominous...
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0346 AM CST MON FEB 27 2012
VALID 011200Z - 061200Z
IN MID-UPPER LEVELS...PAC JET MAX MOVING INTO GREAT BASIN REGION
SHOULD CONTRIBUTE TO DAY-4/1ST-2ND AMPLIFICATION OF WRN-CONUS
SYNOPTIC-SCALE TROUGHING. THIS WILL YIELD SIGNIFICANT SFC
CYCLOGENESIS OVER CENTRAL HIGH PLAINS. HOWEVER...CONSIDERABLE
DIFFERENCES IN SHORTWAVE DETAILS AMONGST MREF MEMBERS...AND BETWEEN
OPERATIONAL SPECTRAL/UKMET/ECMWF...RESULT IN GREAT VARIATION OF
TIMING/DEPTH/TRACK OF THIS LOW...AND OF RELATED BOUNDARIES. THESE
DISCREPANCIES SPREAD APART EVEN MORE DAY-5/2ND-3RD. POLEWARD EXTENT
OF FAVORABLE MOISTURE RETURN ALSO IS IN QUESTION FOLLOWING PASSAGE
OF COLD FRONT DESCRIBED IN DAY-3 OUTLOOK. SOME SVR IS LIKELY DURING
DAY-4/DAY-5 TIME FRAME...GENERALLY FROM SRN PLAINS TO LOWER/MID MS
VALLEY AND OH VALLEY REGIONS. ATTM...HOWEVER...THERE IS TOO MUCH
UNCERTAINTY TO NAIL DOWN SPECIFIC AREA OF 30% UNCONDITIONAL
25 Feb 2012
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0359 AM CST SAT FEB 25 2012
VALID 281200Z - 041200Z
WRN CONUS TROUGHING DESCRIBED IN DAY-3 OUTLOOK WILL LEAD TO
STG/DEEP-LAYER CYCLONE TRACKING FROM CENTRAL HIGH PLAINS TO UPPER MS
VALLEY DAY-4/28TH-29TH. MOST CONFIDENT SVR POTENTIAL...INCLUDING
THREAT FOR TORNADOES...IS OVERNIGHT OVER PORTIONS
OZARKS/MID-SOUTH/ARKLATEX REGIONS. STG MID-UPPER WINDS -- I.E.
50-70 KT AT 500 MB -- AND HODOGRAPH-ENLARGING LLJ SHOULD OVERSPREAD
SFC DEW POINTS INCREASING TO 60S F. FARTHER N...PRIND MOISTURE
RETURN WILL BE MEAGER INTO AREA NEAR SFC LOW...ALTHOUGH STRENGTH OF
DEEP-LAYER LIFT AND WIND FIELDS SHOULD BE SUFFICIENT TO SUPPORT AT
LEAST MRGL SVR THREAT WITH ANY SUSTAINED/SFC-BASED CONVECTION THAT
CAN FORM. POTENTIAL OVER CORN BELT APPEARS TOO CONDITIONAL ATTM TO
EXTEND CATEGORICAL AREA THERE.
MIDWEST SYSTEM SHOULD DEAMPLIFY SOMEWHAT AND OUTPACE GULF MOISTURE
RETURN DAY-5/29TH-1ST...THOUGH SVR POTENTIAL IN SRN
APPALACHIANS/PIEDMONT REGION AND CAROLINAS CANNOT BE RULED OUT.
NEXT SUBSTANTIAL MID-UPPER TROUGH SHOULD CROSS CENTRAL/NRN ROCKIES
DAY-6/1ST-2ND...WITH SFC CYCLOGENESIS OVER CENTRAL HIGH PLAINS.
SOME SVR IS POSSIBLE DAYS 6-7/1ST-3RD FROM SRN/CENTRAL PLAINS TOWARD
LOWER OH VALLEY AS SFC CYCLONE EJECTS FROM HIGH PLAINS...HOWEVER
SPREAD IN VARIOUS MREF/OPERATIONAL PROGS IS TOO LARGE TO ASSIGN
CATEGORICAL OUTLOOK ATTM.
13 Feb 2012
Here we go again...Models hinting at another potential winter storm this up coming weekend. Can we finally cash in this time?
First I'll start off things with this afternoon's 12Z euro run. The Euro showed a phased Gulf low tracking across the Norther Gulf to SAV and then out to sea. Temps were marginal, but no need to focus on that this far out since the SLP placement and temps will change from run to run. Just note this is a classic Miller A track for someone in the region to cash in. Especially if we get a deepening low pressure system rounding the corner of N Florida and up the coast.
The 12Z *GFS* shears out the southern stream energy, and we have a weak Low pressure system moving across the Gulf and crossing the FL peninsula.
The 12Z CMC has a better look than the GFS and very close to phasing like the *EURO*. Temps are colder as well with the 0 degree 850MB line running along to just slight north of I-20 from KJAN-KATL. SLP south of Mobile, AL at 132 with a very moist 700MB field. The SLP turns the corner and continues to track off the SC coast and off to sea.
12Z Ukmet is the furthest NW with SLP tracking through Central AL and cuts inland with a 996MB low off the coast of VA.
12Z Ensembles all support the Miller A idea, temps marginal but again that will change as we get closer.
17 Jan 2012
Models coming into better agreement with one another that an impressive low-amplitude trough will move across the Central US out ahead of a moist airmass. GFS shows mid 60 Tds across much of the Dixie Alley into the Southeast in advance to this developing system. Instability doesn't appear to be lacking, and with a raging low level jet upwards of 65Kts, and mid level jet up to 90+ Kts, there is a growing concern for the possibility of a significant severe weather outbreak across the Southern Plains moving eventually into the SE region. As SPC mentioned there is still some questions needed to be answered such as the "disparity regarding trough motion and geometry," and there is plenty of time to watch the models.
A RELATIVELY INACTIVE PATTERN FOR THUNDERSTORMS WILL PERSIST THROUGH
AT LEAST THE D4-D6 PERIOD WITH NEARLY ZONAL FLOW ACROSS THE CONUS.
MODELS DO INDICATE THAT BY D7...A LARGER SCALE TROUGH WILL DEVELOP
OVER THE W...AFFECTING THE CENTRAL U.S...AND POSSIBLY THE MS VALLEY
REGION BY D8. HOWEVER...THERE IS MUCH DISPARITY REGARDING TROUGH
MOTION AND GEOMETRY...THUS PREDICTABILITY IS TOO LOW TO DEPICT ANY
DIFFERENCES BETWEEN THE 00Z GFS/ECMWF BECOME EVEN LARGER AS WE HEAD
INTO NEXT WEEK. BOTH MODELS AGREE A CHANGE TO A MORE AMPLIFIED
PATTERN IS IN THE WORKS...BUT THE DETAILS ARE QUITE DIFFERENT. THE
GFS IS MORE PROGRESSIVE WITH A POTENT...EARLY WEEK TROUGH OVER THE
CENTRAL CONUS WHILE THE ECMWF SHOWS A CUT OFF LOW DEVELOPING OVER
THE SOUTHWESTERN STATES. CONFIDENCE IN THE FORECAST IS QUITE LOW FOR
LATE IN THE WEEKEND/NEXT WEEK AS A RESULT...BUT I WILL SAY THAT IF
THE LAST FEW RUNS OF THE GFS PAN OUT...WE COULD BE IN FOR A COUPLE
ROUNDS OF SEVERE WEATHER(PERHAPS SIGNIFICANT!) MON INTO TUE.
DEFINITELY STAY TUNED FOR UPDATES ON THAT SITUATION.
Looked at 12Z Hodos and helicity, and they are quite impressive for many cities across Dixie, with the hodos looping clockwise. 0Z GFS had a sharper trough and stronger forcing which suggested a more linear storm mode with embedded tornadoes/supercells. Too early though to really focus on primary storm mode, still some things need answered in regards to the trough.
16 Jan 2012
Wording from SPC:
FOR THE D7-D8 TIME FRAME...MODELS INDICATE A LARGER SCALE TROUGH
DEVELOPING OVER THE WRN SATES...WHICH WILL MOVE INTO THE PLAINS.
WHILE THIS LARGE SCALE FLOW REGIME WILL HAVE A GREATER CHANCE OF
MOISTURE RETURN OVER THE PLAINS...PREDICTABILITY REMAINS LOW.
Hope this isn't premature, but this dynamic system that's been consistently shown on the models especially the GFS, is quickly peaking my interest. You can't over look the dynamics and parameters associated with this system. GFS been consistent with a low-amplitude negative tilt trough moving through the Plains with deepening surface low tracking towards the GL region. The Gulf will be wide open in advance of this developing system with 60 Tds expanding up into portions of the Ohio Valley. As the system deepens low-level jet really ramps up with upwards of 70Kt jet at 850MB, AOA 60Kt jet at 500MB including a 110Kt jet streak at 300MB. Plenty of time to watch the models, but if the 18Z GFS is correct this could be the first significant severe weather event of the new year.
27 Nov 2013 - 22:53
29 Dec 2012 - 13:05
21 Dec 2012 - 20:51
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6 Aug 2012 - 12:47
28 Feb 2012 - 11:13
13 Feb 2012 - 20:15
10 Jan 2012 - 17:33
1 Nov 2011 - 11:40
1 Nov 2011 - 8:43
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