Potential Severe Wx Outbreak Fri/Sat in the Mid-South

[wlfpack81]

Man those 42, 45, 48hr NAM soundings are scary looking for KMEM and KBNA!!!

[PurdueWx80]

New Day2 Outlook from SPC is nearly the same as the previous day3 (valid Friday). There are too many uncertainties (according to them) for an upgrade at this time, but the discussion points out some very important things (and also shows how good they are at their job...for the most part ).

...SYNOPSIS...
PROGRESSIVE SRN STREAM PATTERN IS FCST TO PREVAIL THROUGH PERIOD.
MID/UPPER LEVEL LOW -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY
APPROXIMATELY 20 NM OFFSHORE MRY -- IS FCST TO MOVE INLAND DAY-1 AND
ACROSS GREAT BASIN. THIS FEATURE SHOULD ACCELERATE EWD ACROSS SRN
ROCKIES AND SRN HIGH PLAINS AROUND BEGINNING OF PERIOD...AS NRN
STREAM TROUGH NOW OVER ALBERTA DIGS SEWD. SRN TROUGH THEN WILL
ACCELERATE EWD ACROSS OK AND OZARKS THEN NEWD OVER OH
VALLEY...REACHING ERN INDIANA/WRN OH AREA BY 30/12Z. ASSOCIATED SFC
CYCLONE IS EXPECTED TO MOVE FROM OK NEWD ACROSS OZARKS AND LOWER OH
VALLEY DURING DAY3...DEEPENING CONSIDERABLY WHILE ATTACHED COLD
FRONT SWEEPS SEWD OVER SRN PLAINS AND LOWER MS VALLEY. WARM FRONT
SHOULD LIFT NWD ACROSS TN VALLEY REGION AND NERN AR/MO BOOTHEEL
AREAS...AHEAD OF SFC LOW.

...LOWER MS VALLEY REGION TO CENTRAL/ERN GULF COAST...
POTENTIALLY SIGNIFICANT SEVERE WEATHER EVENT REMAINS POSSIBLE --
PARTICULARLY ALONG AND JUST RIGHTWARD OF SFC CYCLONE TRACK...WHERE
SHEAR/INSTABILITY COMBINATIONS SHOULD BE MAXIMIZED.

BECAUSE OF INTENSE DEEP-LAYER WIND FIELDS...STORMS WILL BE FAST
MOVING AND ANY SUSTAINED/DISCRETE SUPERCELLS THAT DO DEVELOP COULD
PRODUCE LONG TRACK TORNADOES. MAIN FACTOR PRECLUDING OUTLOOK
UPGRADE ATTM REMAINS UNCERTAINTIES REGARDING CONVECTIVE MODE --
PARTICULARLY...DURATION OF ANY THREAT FOR DISCRETE SUPERCELLS IN
THAT ZONE OF ENHANCED SHEAR NEAR SFC CYCLONE...AND POTENTIAL FOR
QUICK TRANSITION TO LINEAR/CLUSTERED CONVECTION. LATEST DRT/MAF
RAOBS INDICATE SOME RELATIVELY STABLE LAYERS IN MIDLEVELS
CORRESPONDING TO INCOMPLETE DEVELOPMENT OF ELEVATED MIXED LAYER.
THIS REGIME ALOFT -- TRANSLATED NEWD -- INDICATES POTENTIAL FOR
RELATIVELY UNCAPPED AIR MASS THAT WOULD SUPPORT RAPID DEVELOPMENT OF
LINEAR CONVECTIVE SYSTEM.

VIGOROUS LOW LEVEL WAA REGIME THROUGH DAY1 AND EARLY DAY2 WILL
COMBINE WITH SFC HEATING TO DESTABILIZE WRM SECTOR ACROSS ERN
PORTION OF OUTLOOK AREA DURING DAY...AMIDST SFC DEW POINTS
MOISTENING INTO 60S F. THIS LEADS TO AFTERNOON MLCAPES 1500-2000
J/KG IN MODIFIED ETA FCST SOUNDINGS. VERTICAL SHEAR WILL BE
FAVORABLE FOR BOTH SUPERCELLS AND DAMAGING BOW ECHOES...WITH 70-80
KT MIDLEVEL FLOWS CONTRIBUTING TO SIMILAR VALUES OF AFTERNOON 0-6 KM
LAYER SHEARS. NARROW AREA OF BACKED SFC FLOW INVOF WARM FRONT
MAY PRODUCE 0-6 KM AND EFFECTIVE LAYER SHEARS AROUND 90 KT...AND 0-1
KM SRH EXCEEDING 200 J/KG.

TSTMS ARE EXPECTED TO BECOME MORE NUMEROUS THROUGHOUT LATE AFTERNOON
INTO EVENING...PERHAPS BACKBUILDING AS FAR AS GULF COASTAL REGION OF
MS/AL/FL PANHANDLE BY END OF PERIOD...WITH DAMAGING WIND BEING MAIN
THREAT BUT SUPERCELLS/TORNADOES STILL POSSIBLE.

...OH VALLEY REGION...
AS SFC LOW CONTINUES TO DEEPEN AND LIFT NEWD...VIGOROUS ISALLOBARIC
FORCING WILL MAINTAIN/EXPAND BOTH BACKING OF SFC FLOW AND LOW LEVEL
CONVERGENCE. THIS WILL CONTRIBUTE TO POTENTIAL FOR STRONGLY
FORCED...POSSIBLY LOW-TOPPED ARC OF CONVECTION MOVING RAPIDLY NEWD
ACROSS REGION OVERNIGHT...WITH POTENTIAL FOR WIND DAMAGE. MAIN
LIMITING FACTOR WILL BE LACK OF SIGNIFICANT SFC-BASED
BUOYANCY...RELATED TO
1. WITH NEWD EXTENT...PROGRESSIVELY MORE INFLOW TRAJECTORIES
ORIGINATING FROM RELATIVELY LOW THETAE AIR MASS OF CONTINENTAL
ANTICYCLONE TO THE E/SE...AND
2. LIKELY WEAKENING TREND IN INSTABILITY WITH TIME...AS DIABATIC
COOLING COUNTERACTS SFC WAA.

..EDWARDS.. 04/28/2005

[wx247]

This situation still looks very dangerous. I would expect that the SPC would upgrade to moderate in the next update.

[PurdueWx80]

This morning's run of the NAM looks like a joke to me...the surface low track does not fit it's upper air pattern whatsoever. While mesoscale processes will help determine where the low forms and travels - the synoptic jet pattern (if correct on the NAM) would not place the surface low over central AR by 00Z Saturday. The only thing I can think of is that the low in AR is what's left of the cyclone that comes out of the Rockies.

200 mb Jet Structure valid 00Z Saturday from NAM

One would expect the surface low to be near or just east of Springfield, MO, not Little Rock, AR:


I, for one, think the "bagginess" in the model's surface chart at 36 hours (i.e. the 'secondary'-looking surface low just south of St. Louis) is a more reasonable placement for a low that would actually develop, if the upper air pattern it shows is correct. Perhaps that is the low that will take over and deepen, leaving the one in AR to fall apart. Hmm.

If this further south run isn't a fluke, then the greatest threat will indeed be from Little Rock to Memphis to Nashville and points south.

[snoopj]

The 1730 outlook shows what everyone suspected, a Moderate Risk zone.

...THERE IS A MDT RISK OF SVR TSTMS CENTRAL/ERN AR AND NRN LA EWD TO
WRN TN AND CENTRAL/NRN MS...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK
FROM ERN TX/ERN OK TO THE OH/TN VALLEYS AND CENTRAL GULF COAST
STATES...

...WIDESPREAD THREAT FOR SIGNIFICANT SEVERE STORMS EXPECTED FRIDAY
AFTERNOON/NIGHT ACROSS PORTIONS OF THE LOWER/MID MS AND LOWER TN
VALLEYS REGION...

...SYNOPSIS...
SHORT WAVE TROUGHS...ONE CURRENTLY MOVING INTO CA/NV AND THE SECOND
APPROACHING THE NRN ROCKIES ATTM...ARE EXPECTED TO PHASE FROM THE
UPPER MS VALLEY TO LOWER TN VALLEY REGION BY FRIDAY NIGHT. A BROAD
AND STRONG /70+ KT/ WSWLY MID LEVEL JET WILL ACCOMPANY THE SRN
STREAM TROUGH AND IS EXPECTED TO NOSE INTO THE LOWER OH/LOWER TN
VALLEYS BY 30/00Z. GIVEN THE BREADTH OF THIS MID-LEVEL JET...50+ KT
WSWLY WINDS WILL EXTEND FROM SRN TX TO THE CENTRAL GULF COAST STATES
DURING MUCH OF THE DAY 2 PERIOD. 12Z NAM IS SLOWER WITH THE MID
LEVEL TROUGH AND FARTHER S WITH THE SURFACE LOW THAN ITS PREVIOUS
RUNS...AND MORE IN AGREEMENT WITH THE GFS/ECMWF/CMC TIMING OF THIS
STORM SYSTEM.

A SURFACE LOW AS INDICATED BY THE 12Z NAM IS EXPECTED TO BE OVER
NORTH CENTRAL TX AT 12Z FRIDAY...WITH THIS LOW DEEPENING AS IT
TRACKS NEWD PER STRONG HEIGHT FALLS WITH THE PHASING MID LEVEL
TROUGHS. THIS LOW SHOULD BE OVER CENTRAL AR BY 30/00Z AND INTO
CENTRAL OH BY 12Z SATURDAY. A WARM FRONT IS EXPECTED TO EXTEND NEWD
FROM THE SURFACE LOW INTO THE OH VALLEY...AND SHOULD REMAIN NEARLY
STATIONARY. NAM SUGGESTS A DIFFERENTIAL HEATING BOUNDARY/ SECONDARY
WARM FRONT WILL DEVELOP FRIDAY FROM CENTRAL AR EWD ALONG THE SRN TN
BORDER.

...OZARKS TO ARKLATEX AND EWD ACROSS TN VALLEY/CENTRAL GULF COAST
STATES...

THUNDERSTORMS...POTENTIALLY SEVERE...ARE EXPECTED TO BE ONGOING AT
THE START OF THE PERIOD ACROSS ERN OK INTO PORTIONS OF SRN MO/SWRN
AR AS A RESULT OF WAA ALONG THE NOSE OF A 50 KT SWLY LLJ. THIS
ACTIVITY IS EXPECTED TO SPREAD NEWD INTO THE LOWER OH VALLEY REGION
ALONG THE NRN WARM FRONT. THESE THUNDERSTORMS WILL BE SUPPORTED BY
DEEP LAYER ASCENT/WAA AS THE LLJ TRANSLATES EWD TO THE LOWER MS
VALLEY AND WITHIN THE EXIT REGION OF THE MID LEVEL JET. ALTHOUGH
MODELS SUGGEST THE MAIN AXIS OF THE MID LEVEL JET WILL BE FROM NRN
TX TO THE OH VALLEY...A SRN STREAM JET APPEARS TO MOVE EWD ACROSS
THE LOWER MS VALLEY PROVIDING SUFFICIENT DIFFLUENT FLOW ALOFT.

THE SRN PERIPHERY OF THIS THUNDERSTORM ACTIVITY IS EXPECTED TO
DEFINE THE DIFFERENTIAL HEATING BOUNDARY FOR THE FORMATION OF THE
SECOND WARM FRONT. THIS BOUNDARY ALONG WITH A COLD FRONT AND DRY
LINE TRAILING SSWWD FROM THE SURFACE LOW OVER CENTRAL AR BY 30/00Z
WILL BE THE PRIMARY FOCI FOR SEVERE STORMS BY LATE FRIDAY AFTERNOON.
THE SLOWER TIMING OF THE MID LEVEL TROUGH WILL ALLOW MORE MOISTURE
TO RETURN NWD WITHIN THE WARM SECTOR ALONG A STRENGTHENING SLY LLJ.
THIS MOISTURE COMBINED WITH STEEP LAPSE RATES AND SURFACE HEATING
WILL RESULT IN A VERY UNSTABLE AIR MASS /MLCAPE 2500+ J/KG/ ACROSS
THE MODERATE RISK AREA. STRONG DEEP LAYER SHEAR /50-60 KT/ WILL BE
FAVORABLY ORIENTED FOR SUPERCELLS WITH THE POTENTIAL FOR SIGNIFICANT
TORNADOES AND HAIL...ESPECIALLY WITHIN THE MODERATE RISK AREA ALONG
AND EAST OF THE SURFACE LOW TRACK.

THIS LATE AFTERNOON/EARLY EVENING SEVERE ACTIVITY IS EXPECTED TO
CONGEAL INTO A SQUALL LINE AND MOVE ESEWD ACROSS THE TN VALLEY AND
CENTRAL GULF COAST STATES WITH DAMAGING WINDS BECOMING THE PRIMARY
THREAT FRIDAY NIGHT.

...OH VALLEY REGION...
12Z NAM SUGGESTS SOME BREAKS IN THE CLOUDS ARE POSSIBLE ACROSS THE
LOWER OH VALLEY INTO SRN IND/WRN KY PROMOTING AREAS OF MODERATE
INSTABILITY BY EARLY FRIDAY AFTERNOON. DEEP LAYER SHEAR WOULD BE
SUFFICIENT FOR SUPERCELLS WITH THUNDERSTORM ACTIVITY IN THIS AREA.

...ERN TX...
ALTHOUGH MUCH OF ERN TX WILL BE LOCATED SOUTH OF THE MID LEVEL JET
AND THUS WILL HAVE RELATIVELY WARM MID LEVEL TEMPERATURES...STRONG
SURFACE HEATING MAY BE STRONG ENOUGH TO OVERCOME THE CAP BY MID-LATE
FRIDAY AFTERNOON. IF STORMS CAN DEVELOP...DEEP LAYER SHEAR AND
MODERATE INSTABILITY WILL SUPPORT SUPERCELLS WITH SIGNIFICANT HAIL
LIKELY GIVEN STEEP LAPSE RATES.

..PETERS.. 04/28/2005

[Huckster]

Here's the latest from the 1730 day two outlook from SPC...

...OZARKS TO ARKLATEX AND EWD ACROSS TN VALLEY/CENTRAL GULF COAST
STATES...

THUNDERSTORMS...POTENTIALLY SEVERE...ARE EXPECTED TO BE ONGOING AT
THE START OF THE PERIOD ACROSS ERN OK INTO PORTIONS OF SRN MO/SWRN
AR AS A RESULT OF WAA ALONG THE NOSE OF A 50 KT SWLY LLJ. THIS
ACTIVITY IS EXPECTED TO SPREAD NEWD INTO THE LOWER OH VALLEY REGION
ALONG THE NRN WARM FRONT. THESE THUNDERSTORMS WILL BE SUPPORTED BY
DEEP LAYER ASCENT/WAA AS THE LLJ TRANSLATES EWD TO THE LOWER MS
VALLEY AND WITHIN THE EXIT REGION OF THE MID LEVEL JET. ALTHOUGH
MODELS SUGGEST THE MAIN AXIS OF THE MID LEVEL JET WILL BE FROM NRN
TX TO THE OH VALLEY...A SRN STREAM JET APPEARS TO MOVE EWD ACROSS
THE LOWER MS VALLEY PROVIDING SUFFICIENT DIFFLUENT FLOW ALOFT.

THE SRN PERIPHERY OF THIS THUNDERSTORM ACTIVITY IS EXPECTED TO
DEFINE THE DIFFERENTIAL HEATING BOUNDARY FOR THE FORMATION OF THE
SECOND WARM FRONT. THIS BOUNDARY ALONG WITH A COLD FRONT AND DRY
LINE TRAILING SSWWD FROM THE SURFACE LOW OVER CENTRAL AR BY 30/00Z
WILL BE THE PRIMARY FOCI FOR SEVERE STORMS BY LATE FRIDAY AFTERNOON. THE SLOWER TIMING OF THE MID LEVEL TROUGH WILL ALLOW MORE MOISTURE
TO RETURN NWD WITHIN THE WARM SECTOR ALONG A STRENGTHENING SLY LLJ.
THIS MOISTURE COMBINED WITH STEEP LAPSE RATES AND SURFACE HEATING
WILL RESULT IN A VERY UNSTABLE AIR MASS /MLCAPE 2500+ J/KG/ ACROSS
THE MODERATE RISK AREA. STRONG DEEP LAYER SHEAR /50-60 KT/ WILL BE
FAVORABLY ORIENTED FOR SUPERCELLS WITH THE POTENTIAL FOR SIGNIFICANT
TORNADOES AND HAIL...ESPECIALLY WITHIN THE MODERATE RISK AREA ALONG
AND EAST OF THE SURFACE LOW TRACK.

THIS LATE AFTERNOON/EARLY EVENING SEVERE ACTIVITY IS EXPECTED TO
CONGEAL INTO A SQUALL LINE AND MOVE ESEWD ACROSS THE TN VALLEY AND
CENTRAL GULF COAST STATES WITH DAMAGING WINDS BECOMING THE PRIMARY
THREAT FRIDAY NIGHT.

There is definitely some seriously dry air out in west Texas right now. Check out the latest obs from west Texas and New Mexico:

http://www.srh.noaa.gov/maf/cgi-bin/version.php?pil=RWRMAF&cwi=1&n=0

Notice that Alpine, TX is reporting a temp of 81 degrees, a dewpoint of 9 degrees, and a RH of 6%.

[jkt21787]

OK, some serious doubts are now arising about this. Models are consistently going much further south and are also much weaker. Low track on 18z NAM now going just south of Memphis. If this is the case, than this event doesn't happen, at least where its predicted now.

Could this be a fluke? Because the models are really hatching on to this trend. Purdue, could this be the situation that you hinted at last night with poor sampling when the system was still offshore and now we are seeing the changes as the system is more fully sampled?

Not believing all of this yet, but that could change significantly after 00z runs tonight. This is a very discouraging trend at this point.

[Brett Adair]

OK, some serious doubts are now arising about this. Models are consistently going much further south and are also much weaker. Low track on 18z NAM now going just south of Memphis. If this is the case, than this event doesn't happen, at least where its predicted now.

Could this be a fluke? Because the models are really hatching on to this trend. Purdue, could this be the situation that you hinted at last night with poor sampling when the system was still offshore and now we are seeing the changes as the system is more fully sampled?

Not believing all of this yet, but that could change significantly after 00z runs tonight. This is a very discouraging trend at this point.

I agree. The threat may actually shift further south into MS/AL. Especially with the developing LLJ/MLJ maximums over the region by 30/06z. Things may get cranking with a derecho as BHM hodos curve, but are a little smaller.

CAPE : Near 1000
SWEAT: Near 300
SRH - 500+
2m AGL Dewpoint : 66
850 MB Wind : 58KTs
500 MB WIND : 62 KTs

Interesting setup panning out with the Talladega SuperSpeedway event this weekend. I will personally be chasing since I live in the Talladega County area. Will post updates after work tonight. (1 AM CDT)

The further south the low pushes, the more significant a disaster could be for the Talladega area even if a weakening trend has been projected.

[jkt21787]

I agree. The threat may actually shift further south into MS/AL. Especially with the developing LLJ/MLJ maximums over the region by 30/06z. Things may get cranking with a derecho as BHM hodos curve, but are a little smaller.

I really hate to hear you say that, LOL. I really thought this was going to be the one for Memphis, now it just looks like everything else this year, south of us. I am ready to give up!!

[Huckster]

I agree. The threat may actually shift further south into MS/AL. Especially with the developing LLJ/MLJ maximums over the region by 30/06z. Things may get cranking with a derecho as BHM hodos curve, but are a little smaller.

I really hate to hear you say that, LOL. I really thought this was going to be the one for Memphis, now it just looks like everything else this year, south of us. I am ready to give up!!

I think I will pretty much give up on the prospects of any storms around here, unless I see a reason to think differently. Everything has been NORTH of me, in spite of the fact that hail has been reported in my parish (East Baton Rouge) twice already this year. I barely saw any sprinkles with either of those two hail storms. Looks like rain chances might be on the increase next week around here, but I haven't heard anything about severe weather yet.

[PurdueWx80]

I honestly think the worst of the severe weather will include Little Rock (barely), Memphis, Nashvillle on down to as far south as Jackson, MS (maybe) - Memphis looks to be in the thick of it if you ask me. Even though the 18Z NAM has the low west or southwest of Memphis at 00z, it zooms it to the NNE towards southern IL/IN after dark, so it would pass to your west. I'm not totally set on the surface low track yet, although we're closing in on the event so there's not much time for them to change/improve/worsen. Temps should easily make the 80's in Memphis and dewpoints will likely inch up into the mid or even upper 60's - with the cool/dry mid-level air over the rich, warm air at the surface, CAPEs will be very high. I think the amount of dry air in the mix (in mid-levels) will keep it partly to mostly sunny in western TN and surrounding areas until the supercells develop.

Further north in KY (basically along the warm front), I still am in the frame of mind that tornadoes spinups are likely because of very low LCL's and extremely high relative helicity values - it doesn't take much instability in this kind of setup to develop tornadoes, even if they are short-lived. Further south, any tornado development will depend on the amount of low-level backing of the winds (to the SSE or SE) ahead of the surface low. Otherwise, it definitely looks like some widespread wind damage is possible with the kind of wind fields showing up on today's model runs. I wouldn't doubt if we see numerous reports of 2-4" hail as well, especially in AR, MS and TN.

[jkt21787]

Thanks Purdue. I am not ready to write this off yet by any mean. I have been talking to others as well on other boards (they are probably getting tired of me, I have been a whiner and "question machine" today LOL), and they remain overall pretty optimistic about it.

It continues to be a wait and see game...

[PurdueWx80]

jkt - this is about as good a sounding as you can get for tornadoes and supercells - it's from the 18Z NAM for Memphis. I never pay attention to the instability parameters on the 6 or 18Z runs - it's always underdone for whatever reason.

[jkt21787]

Thanks Purdue for that, that is pretty classic. Especially if the instability is underdone, than that is even more serious. Let's see what 00z brings us in a couple of hours. At that point I will likely make the decision on what this brings us.

[jkt21787]

New NAM coming in shows low track further south again (albeit very slightly). Still shows instability favorable for severe by 0z Sat, but not anywhere near the values we were seeing forecasted here 24 hours ago. Still plenty of shear to work with.

My guess is that the best chances for severe weather will be along and south of I-40, with the highest threat from Pine Bluff Arkansas to Oxford MS. I am calling for a moderate risk for extreme SW Tn, East central and Southeast Arkansas, and much of north Mississippi. Based on what I am seeing, I don't see a high risk situation.

Still not sure whether supercells or squall line dominate. Either way, feel the strong tornado threat is not as high as before. The long track threat will still be there because of fast storm motion.

[Brett Adair]

New NAM coming in shows low track further south again (albeit very slightly). Still shows instability favorable for severe by 0z Sat, but not anywhere near the values we were seeing forecasted here 24 hours ago. Still plenty of shear to work with.

My guess is that the best chances for severe weather will be along and south of I-40, with the highest threat from Pine Bluff Arkansas to Oxford MS. I am calling for a moderate risk for extreme SW Tn, East central and Southeast Arkansas, and much of north Mississippi. Based on what I am seeing, I don't see a high risk situation.

Still not sure whether supercells or squall line dominate. Either way, feel the strong tornado threat is not as high as before. The long track threat will still be there because of fast storm motion.

This evening we are definately seeing the maritime tropical air coming onshore down on the NW Gulf Coastline....this is something that we are going to have to watch since the 70 degree isodrotherm is hugging the coastline. JAN had there doubts that this thing wouldn't crank up points about 62-66 but I believe this is about to get really hairy. Mid level/Low level jets will congeal and strengthen late in the afternoon hours and mean mid level mixing will initiate early into the mid afternoon it seems with little cap in place across portions of AR and WRN MS. LCL heights will lower given higher moisture content evident on METAR's currently and give higher strong/violent, long track tornado potential. This could actually help in elongating the duration of this event. I actually see a possibility of more tornadoes into AL now with forecast hodo's becoming a little larger and curved. SRH values of 400+ will enhance this threat greatly. I still see a possible derecho in the developmental stages given the pattern setting up. I am just more concerned now with higher SBCAPE patterns evolving and lower LCL's which will likely increase tornadic potential and wind damage threats. More in the morning....night all.

[PurdueWx80]

Memphis and Little Rock metro areas are he places to watch out. That outflow boundary just south of the 2 cities should become the focus for tornadic development later, and as southerly winds pick up this afternoon with the strengthening low-level jet, that boundary will move to the north. I'm a little surprised at the amount of cloudcover over the entire region - it will hamper the extreme destabilization depicted on some models in the past few days, but moisture return has bene plentiful, and any breaks in cloudcover should allow meso-gamma scale pockets of instabillity to force storm development late this afternoon.

Looking back over the past few days of model runs, it has become apparent that the NAM and GFS overdid the amount of phasing/consolidating of upper energy. Looking at the WV loop, the vort that came into California is all strung out, rather than being one solid piece of energy with a weaker tail as was depicted a few days ago. That, and the fact that upper level wind fields don't support the kind of cyclogenesis that was forecast (notice there is now no major surface low forecast until northern stream energy comes into play in the eastern OH Valley late tonight). All of this has resulted in a further south and weaker solution (low and mid-level windfields aren't as impressive as was forecast previously). Still, some strong tornadoes and very large hail (in addition to flooding rainfall) are possible late this afternoon where the SPC has a moderate risk.

[jkt21787]

Well, I'm just about ready to call this one. Storms aren't showing any real organization. Every time we have seen some hail core try to develop, it collapses soon after. Cap or whatever, its just not happening. Still expect we'll see isolated severe weather in TN, MS, SE ARK, and maybe N LA, but don't see much more of a threat for tornadoes, except for a maybe a brief spinup. Hail will likely be the threat for now, before things line up completely and winds become a threat, Given what I am seeing thus far, I not sure on even that.

Honestly, its hard to believe what this system turned out to be given what it looked like less than 48 hours ago. I NEVER would have expected to see a such a shift in the models, and has certainly made me learn some lessons. I really feel sorry for the chasers who have driven hundreds of miles or more because of the early indications and only to be left with what appears to mostly be a bust.

Again, its not completely over, but I feel the threat for an outbreak and even an "event" of large proportions is, at least as far as tornadoes. Maybe things can light up as this heads east, but I'm not getting my hopes up.

[wlfpack81]

2 Thoughts Here:

1) Still a nice looking tstorm heading towards Memphis as we speak. Radar indicating 70%-POH / 40%-POH / 0.75in size as of 6:45 CDT. So while this isn't severe yet it'll give a decent quick lashing to s-ern parts of Memphis.

2) It's actually a good thng w-ern TN didn't experience a huge outbreak. Yes I do have family there and that's one reason but another is that area is so heavily populated. About the only good thing about having outbreaks in the Plains states is that the population density is a lot less, so you have less injuires, deaths, damage yet chaser can still get their thrills by seeing storms. I should to think if that May 3, 1999 outbreak here in OK had instead taken place in e-ern AR / w-ern TN

[wlfpack81]

Severe tstorm warning in Memphis was issued at 645pm CDT and goes until 715pm CDT. Doesn't surprise me they issued that warning when they did since it did look fairy impressive on the radar and the indications for hail were 70% / 40% / 0.75in as I mentioned in my earlier post. Talked with one of my sisters who lives there and hail can be confirmed as she saw some near her job. I didn't ask her to describe how big it was though.