Cheeznado Posted March 22, 2011 Share Posted March 22, 2011 Models have been pretty consistent in showing a low pressure area in the TN area at 00Z, CAPE not super high but the GFS shows nice hodographs with SW surface winds veering to westerly at 500MB. I expect a few supercells somewhere in northern MS, central TN to northern AL, might consider a chase if trends still look good in a few days. Link to comment Share on other sites More sharing options...
eyewall Posted March 22, 2011 Share Posted March 22, 2011 It will be interesting to watch. I have my eye on tomorrow for NC but I worry about surface mositure a bit. Link to comment Share on other sites More sharing options...
Cheeznado Posted March 22, 2011 Author Share Posted March 22, 2011 Models having difficulty resolving this- new Euro and GGEM much weaker with the low, looks like a few days more before the forecast becomes clearer. Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 24, 2011 Share Posted March 24, 2011 Day 3 DAY 3 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0226 AM CDT THU MAR 24 2011 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS SATURDAY ACROSS THE NORTHERN GULF STATES INTO PARTS OF THE TENNESSEE AND LOWER MISSISSIPPI VALLEYS... ...SYNOPSIS... MODELS INDICATE LITTLE CHANGE TO THE GENERAL LARGE-SCALE PATTERN THROUGH THIS FORECAST PERIOD. SHORT WAVE IMPULSES EMANATING FROM A STRONG MID LATITUDE PACIFIC JET...WHICH MAY BE GRADUALLY NOSING TOWARD THE PACIFIC COAST...CONTINUE TO DIG WITHIN A STRONGER BELT OF FLOW DIVERTED SOUTH OF AN UPPER RIDGE OVER CENTRAL CANADA... INTO A CONFLUENT REGIME ACROSS THE MIDDLE MISSISSIPPI VALLEY THROUGH THE MID ATLANTIC COAST. ONE OF THESE FEATURES MAY BE ACCELERATING INTO THIS LATTER REGIME EARLY SATURDAY. WHILE AN UPSTREAM IMPULSE DIGS THROUGH THE GREAT BASIN...A STRONG UPPER JET WITHIN THE CREST OF BROAD SUBTROPICAL RIDGING BUILDING OVER THE MEXICAN PLATEAU AND GULF OF MEXICO...IS PROGGED TO NOSE EASTWARD THROUGH THE REMAINDER OF THE GULF COAST REGION. IN LOWER LEVELS...A WAVE ALONG A SLOWLY RETREATING FRONTAL ZONE OVER THE RED RIVER VALLEY AT 12Z SATURDAY PROBABLY WILL WEAKEN... WHILE MIGRATING TOWARD THE NORTHERN GULF STATES. BUT...30 TO 40 KT SOUTHWESTERLY LOW-LEVEL FLOW IS EXPECTED TO MAINTAIN AN INLAND RETURN FLOW OF GULF MOISTURE...WITH LOWER/MID 60S SURFACE DEW POINTS BECOMING COMMON THROUGH THE DAY SATURDAY...FROM THE WESTERN GULF COAST THROUGH MUCH OF THE CENTRAL AND EASTERN GULF COAST STATES. COUPLED WITH AT LEAST MODEST STEEPENING OF MID-LEVEL LAPSE RATES ON MODERATELY STRONG WEST SOUTHWESTERLY TO WESTERLY MID-LEVEL FLOW...THIS IS EXPECTED TO CONTRIBUTE TO CONSIDERABLE DESTABILIZATION AND THUNDERSTORM ACTIVITY ACROSS THE MID SOUTH AND SOUTHEAST STATES. ...GULF/SOUTH ATLANTIC COAST STATES INTO MID SOUTH... LOWER/MID TROPOSPHERIC WARM ADVECTION ALONG AND NORTH OF THE FRONTAL ZONE IS EXPECTED TO SUPPORT CLUSTERS OF STORMS THROUGH THE PERIOD. HOWEVER...MID-LEVEL INHIBITION MAY REMAIN WEAK ENOUGH...WITHIN A CORRIDOR ALONG AND JUST SOUTH OF THE FRONT...TO ALLOW THE DEVELOPMENT OF BOUNDARY LAYER BASED STORMS DURING THE AFTERNOON AND EVENING HOURS. HIGHEST PROBABILITIES FOR THIS APPEAR FROM PARTS OF SOUTHEAST ARKANSAS EASTWARD THROUGH FAR SOUTHERN TENNESSEE AND ADJACENT NORTHERN MISSISSIPPI/ALABAMA AND GEORGIA. DETAILS REMAIN UNCLEAR...BUT GIVEN THE FAVORABLE THERMODYNAMIC ENVIRONMENT...A SHEARED AND MODERATELY STRONG /30-40+ KT/ DEEP LAYER MEAN FLOW IS EXPECTED TO BE SUPPORTIVE OF ORGANIZED STORMS CLUSTERS...AS WELL AS SUPERCELLS. A FEW TORNADOES MAY BE POSSIBLE...IN ADDITION TO THE RISK FOR LARGE HAIL AND DAMAGING WIND GUSTS. Day4-8 DAY 4-8 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0347 AM CDT THU MAR 24 2011 VALID 271200Z - 011200Z ...PREDICTABILITY TOO LOW TO DELINEATE A REGIONAL SVR RISK AREA... MEDIUM RANGE GUIDANCE GENERALLY INDICATES THAT THE PREVAILING BLOCKING PATTERN WILL WEAKEN...OR BECOME LESS PROMINENT...DURING THIS FORECAST PERIOD. AS THIS PROCEEDS...THE ECMWF REMAINS SUGGESTIVE THAT ONE OF THE SIGNIFICANT SHORT WAVE IMPULSES EMANATING FROM A STRONG MID-LATITUDE PACIFIC JET COULD AMPLIFY AND SUPPORT STRONG CYCLOGENESIS SOMEWHERE FROM THE LEE OF THE SOUTHERN ROCKIES INTO THE ATLANTIC SEABOARD...AT SOME POINT NEXT WEEK. IF THIS OCCURS...IT APPEARS LIKELY TO COINCIDE WITH CONTINUED MOISTENING OF THE GULF BOUNDARY LAYER...WHICH COULD SUPPORT A SEASONABLY STRONG INLAND RETURN FLOW...AND POTENTIAL FOR A SIGNIFICANT SEVERE WEATHER OUTBREAK. HOWEVER...THE RUN TO RUN VARIABILITY OF THE ECMWF HAS BEEN SUBSTANTIAL...AND THE SPREAD BEGINS TO INCREASE AMONG THE MODELS AND MODEL ENSEMBLES AS EARLY AS THE BEGINNING OF THE PERIOD. AS A RESULT...UNCERTAINTY REMAINS MUCH TOO LARGE TO CONFIDENTLY ASSESS THE SEVERE WEATHER THREAT... AND ATTEMPT TO DELINEATE A REGIONAL SEVERE RISK AREA. Link to comment Share on other sites More sharing options...
Cheeznado Posted March 24, 2011 Author Share Posted March 24, 2011 Still looking like a decent event with a few tornadoes- (mods, please fix the typo in the thread header) Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 24, 2011 Share Posted March 24, 2011 Still looking like a decent event with a few tornadoes- Yea it still looks good. 12Z NAM STP is pretty high. Looking at latest 12Z NAM soundings KBHM/HSV has CAPE values up towards 1500 J/KG with very high helicity values over 500, and EHI values in the 3.00-6.00 range. KATL keeps lower CAPE values above 500 but less than 1000 J/KG, but also has high shear in place with EHI in the 1.00-3.00 range, helicity 300-550 with SFC-1KM shear over 20 M/S( helicity in the 250-350 range). Soundings showed little to no CIN in place. Hour 63 66 Link to comment Share on other sites More sharing options...
eyewall Posted March 24, 2011 Share Posted March 24, 2011 After yesterdays's frustration I am tempted to do a dixie alley chase on this one if I can get another person or two to chip in on gas. Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 24, 2011 Share Posted March 24, 2011 Latest from BMX: Their current thinking is more of a MCS event and say severe weather confidence is increasing, but tornado threat decreasing. AN UNSETTLED PATTERN FOR THE WEEKEND AND REALLY MUCH OF EARLY NEXTWEEK. SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AS SURFACE LOW PRESSURE SHIFTS THROUGH THE STATE ALONG OR NEAR A STALLED FRONTAL BOUNDARY. UPPER LEVEL PATTERN CONSISTS OF ZONAL FLOW WITH EMBEDDED SHORTWAVE ENERGY WHICH SHOULD WORK FAVORABLY WITH GOOD SURFACE BASED INSTABILITY THROUGHOUT THE DAY SATURDAY. THERE REMAINS SOME THREAT OF SEVERE WEATHER OVER THE WEEKEND ALTHOUGH DETAILS REMAIN BURIED IN THE MESOSCALE. STILL LIKE THE IDEA OF A MORE MCS DRIVEN EVENT ALTHOUGH FORECAST SOUNDINGS ARE ALSO SUPPORTIVE OF SUPERCELLS. EVERYONE STANDS TO SEE A CHANCE OF SOME RAINFALL OVER THE WEEKEND HOWEVER THE BETTER CHANCES WILL BE NEAR THE BOUNDARY ACROSS THE NORTHERN HALF OF THE STATE. HWO: .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. THERE IS A CHANCE OF SEVERE THUNDERSTORMS...INCLUDING THE THREAT OF DAMAGING WINDS AND LARGE HAIL...ACROSS PORTIONS OF CENTRAL ALABAMA DURING THE SATURDAY THROUGH MONDAY TIME FRAME. THE SEVERE WEATHER THREAT WILL NOT BE CONTINUOUS DURING THIS TIME...BUT MAY COME IN SEVERAL WAVES. THE MOST LIKELY TIME FOR THE FIRST WAVE OF STORMS IS SATURDAY AFTERNOON AND SATURDAY NIGHT. CONFIDENCE IN THE SEVERE THREAT FOR SATURDAY IS INCREASING...BUT THE TORNADO THREAT IS DECREASING. THEREFORE THE MAIN THREATS WILL BE DAMAGING WINDS AND LARGE HAIL. A FEW STRONG TO SEVERE THUNDERSTORMS MAY CONTINUE OR REDEVELOP ON SUNDAY...MAINLY ACROSS THE SOUTH...AS A COLD FRONT PUSHES THROUGH THE AREA. ANOTHER ROUND OF SEVERE WEATHER COULD BE POSSIBLE AGAIN ON MONDAY ACROSS THE SOUTH IF THE FRONT STALLS OVER THE AREA. BECAUSE THE COMPUTER MODELS ARE STILL HAVING A HARD TIME DEALING WITH THE SPECIFICS...MOST NOTABLY THE LOCATION AND MOVEMENT OF THE COLD FRONT...FORECAST CONFIDENCE REMAINS LOW FOR LATE SUNDAY INTO MONDAY AT THIS TIME. .SPOTTER INFORMATION STATEMENT... ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT MAY BE NECESSARY OVER THE WEEKEND. Link to comment Share on other sites More sharing options...
eyewall Posted March 24, 2011 Share Posted March 24, 2011 Bleh no chance of a chase if it is an MCS threat. Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 24, 2011 Share Posted March 24, 2011 Bleh no chance of a chase if it is an MCS threat. Yea. But to have an MCS event doesn't that mean you need Unidirectional winds. Looking at KBHM hodographs off of 12Z NAM it doesn't look Unidirectional to mean. That or am I just looking at it or reading it wrong? KBHM at 8pm Link to comment Share on other sites More sharing options...
eyewall Posted March 24, 2011 Share Posted March 24, 2011 Yea. But to have an MCS event doesn't that mean you need Unidirectional winds. Looking at KBHM hodographs off of 12Z NAM it doesn't look Unidirectional to mean. That or am I just looking at it or reading it wrong? KBHM at 8pm Hodo looks good here for supercells on paper with high shear (I am assuming 0-6km?) that is not unidirectional (clockwise hodo)and helicity off the charts. I am guessing the NWS is not entirely trusting this right now? The MCS would require less shear than this in order for more cells to appear between discrete supercells and start the collisions or formation of a line. At least that is what i gather. If the shear is decent but not great you get favorable conditions for alot of cell formation on gust fronts which could be troublesome if you want discrete storms to chase. Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 25, 2011 Share Posted March 25, 2011 I wouldn't doubt a day 2 moderate risk tomorrow. Probably for NE Mississippi into N Al and maybe into W Georgia. NAM has STP values over 7 across much of N AL as well as high EHI values being shown. Strong tornadoes seems possible, but where will depend on where the Warm front stalls out at. 0-1KM Hodos really mean business. 18Z NAM STP Link to comment Share on other sites More sharing options...
audioguy3107 Posted March 25, 2011 Share Posted March 25, 2011 Also remember some if not a majority of our sig. outbreaks come with just this type of setup with the warm front draped W to E across the deep S. The parameters here look suspiciously similar to that Sunday in March 2008. Dont remember the strength of the low though. We weren't upgraded to a Mod risk until about 10:00 AM that day once the event was unfolding (and then high risk later). CAPE increased very rapidly that afternoon once things got underway. Link to comment Share on other sites More sharing options...
eyewall Posted March 25, 2011 Share Posted March 25, 2011 Looking at these hodos and shear values I would expect a more supercellular mode. Are the wfo's still saying mcs? If so I wonder what the thinking is on that. Sent from my DROIDX using Tapatalk Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 25, 2011 Share Posted March 25, 2011 Looking at these hodos and shear values I would expect a more supercellular mode. Are the wfo's still saying mcs? If so I wonder what the thinking is on that. Sent from my DROIDX using Tapatalk Yea BMX still thinking mainly MCS with damaging winds/large hail of main concern, they said isolated tornado threat is highest closer to the warm-front. FFC mentions increased instability thanks to Carolina wedge, that and warm-front increasing helicity will allow storms to rotate, but they expect them to be elevated. They did mention West Central Georgia for a better threat where instability/shear coincide, but they believe hail will be the primary threat. They also mentioned scroll-line possible Saturday evening, but high helicity/cape present could pose a risk of rotating storms. HSV same thing damaging winds/large hail of greatest concern with possible isolated tornadoes. Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 25, 2011 Share Posted March 25, 2011 Latest from SPC MODEL CONSENSUS SUGGESTS THE GREATEST COVERAGE OF THUNDERSTORM ACTIVITY WILL BE ALONG THE BOUNDARY FROM NRN MS ESEWD ACROSS NCNTRL AL INTO CNTRL GA. THIS CORRIDOR IS ALONG THE NRN EDGE OF MODERATE INSTABILITY AND ON THE SRN EDGE OF BROAD BAND OF STRONG MID-LEVEL FLOW. FORECAST SOUNDINGS ACROSS NRN MS AND NRN AL AT 21Z SATURDAY SHOW MLCAPE CAPE AROUND 2000 J/KG WITH 50 KT OF DEEP LAYER SHEAR AND STEEP MID-LEVEL LAPSE RATES. THIS ENVIRONMENT SHOULD BE SUPPORTIVE OF SUPERCELL DEVELOPMENT WITH LARGE HAIL ACCOMPANYING THE MORE DOMINANT STORMS. IN ADDITION...TORNADOES MAY OCCUR AS SUPERCELLS MATURE AND THE LOW-LEVEL JET STRENGTHENS SATURDAY EVENING. THE BIRMINGHAM FORECAST SOUNDING EARLY SATURDAY EVENING SHOWS 0-3 KM STORM RELATIVE HELICITIES AROUND 400 M2/S2 SUGGESTING A THREAT FOR STRONG TORNADOES WILL BE POSSIBLE. A CLUSTERING OF TORNADOES MAY OCCUR ACROSS NRN MS AND NCNTRL AL WHERE INSTABILITY...SHEAR AND LIFT IS FORECAST TO BE MAXIMIZED. FURTHER EAST SOUTHEAST ALONG THE BOUNDARY IN CNTRL GA...MODEL FORECASTS ARE ALSO IN AGREEMENT WITH THUNDERSTORM DEVELOPMENT SATURDAY AFTERNOON. FORECAST SOUNDINGS AROUND MACON AT 21Z SATURDAY SHOW MLCAPE VALUES OF 1000 J/KG WITH 50 KT OF DEEP LAYER SHEAR. THIS SHOULD BE SUFFICIENT FOR A SEVERE THREAT WITH SUPERCELL DEVELOPMENT POSSIBLE. LARGE HAIL AND AN ISOLATED TORNADO THREAT MAY ACCOMPANY THE STRONGER CELLS ESPECIALLY IF STORMS REMAIN DISCRETE. HOWEVER...THERE IS A POSSIBILITY THAT A LINEAR MCS COULD DEVELOP WHICH WOULD MAKE WIND DAMAGE THE PRIMARY THREAT. Link to comment Share on other sites More sharing options...
eyewall Posted March 25, 2011 Share Posted March 25, 2011 It would be a hell of a drive but it is soo tempting to chase this! Link to comment Share on other sites More sharing options...
CandymanColumbusGA Posted March 25, 2011 Share Posted March 25, 2011 Eyewall... I think this is a great one to chase... If I were to chase this storm I would be somewhere between Huntsville and Bham. The low level jet is looking solid. The STP is off the charts. Plenty of warm air and dew points in the low 60s. I also would not be surprised to see a few cells develop in the warm sector (near my viewing area) and drop some good hail and winds. The tornado threat looks to be closer to the warm front. Let's get this great last week of March started! Link to comment Share on other sites More sharing options...
eyewall Posted March 25, 2011 Share Posted March 25, 2011 Eyewall... I think this is a great one to chase... If I were to chase this storm I would be somewhere between Huntsville and Bham. The low level jet is looking solid. The STP is off the charts. Plenty of warm air and dew points in the low 60s. I also would not be surprised to see a few cells develop in the warm sector (near my viewing area) and drop some good hail and winds. The tornado threat looks to be closer to the warm front. Let's get this great last week of March started! Yeah according the google maps I am looking at a solid 10-12 hour trip just to get to the target area if I went. Link to comment Share on other sites More sharing options...
ATL_Militarypolice Posted March 25, 2011 Share Posted March 25, 2011 Latest from BMX in HWO. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. THERE IS A CHANCE OF SEVERE THUNDERSTORMS ON SATURDAY THROUGH EARLY SUNDAY...INCLUDING THE THREAT OF DAMAGING WINDS AND LARGE HAIL...ACROSS MOST OF CENTRAL ALABAMA. THE MAIN THREAT WINDOW WILL BE FROM AROUND 10 AM SATURDAY...THROUGH 6 AM SUNDAY...WITH THE HIGHEST CHANCES ALONG NORTH OF INTERSTATE 85. THERE WILL ALSO BE AN INCREASING THREAT OF TORNADOES SATURDAY EVENING BETWEEN 6 PM AND MIDNIGHT...MAINLY ALONG AND NORTH OF I-20. SHOWERS AND THUNDERSTORMS WILL CONTINUE UNTIL LATE SUNDAY MORNING ACROSS THE SOUTHEAST... HOWEVER THE SEVERE THREAT WILL BEGIN TO DECREASE THROUGH SUNDAY MORNING. Sent using my thumbs on Tapatalk Link to comment Share on other sites More sharing options...
eyewall Posted March 25, 2011 Share Posted March 25, 2011 Latest from BMX in HWO. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. THERE IS A CHANCE OF SEVERE THUNDERSTORMS ON SATURDAY THROUGH EARLY SUNDAY...INCLUDING THE THREAT OF DAMAGING WINDS AND LARGE HAIL...ACROSS MOST OF CENTRAL ALABAMA. THE MAIN THREAT WINDOW WILL BE FROM AROUND 10 AM SATURDAY...THROUGH 6 AM SUNDAY...WITH THE HIGHEST CHANCES ALONG NORTH OF INTERSTATE 85. THERE WILL ALSO BE AN INCREASING THREAT OF TORNADOES SATURDAY EVENING BETWEEN 6 PM AND MIDNIGHT...MAINLY ALONG AND NORTH OF I-20. SHOWERS AND THUNDERSTORMS WILL CONTINUE UNTIL LATE SUNDAY MORNING ACROSS THE SOUTHEAST... HOWEVER THE SEVERE THREAT WILL BEGIN TO DECREASE THROUGH SUNDAY MORNING. Sent using my thumbs on Tapatalk The bad news is there is prime timing for TORs is mostly as it is getting dark. Link to comment Share on other sites More sharing options...
CandymanColumbusGA Posted March 25, 2011 Share Posted March 25, 2011 The bad news is there is prime timing for TORs is mostly as it is getting dark. I will tell you guys this much... Our in house computer model has the heaviest activity moving through around noon... Then it has some pop up showers and thunderstorms later in the afternoon/evening, though it doesn't have these as particularly heavy storms. Though that's not to say it's high enough resolution to depict the storms... Should be fun to watch tomorrow! I know I will have to come in on my day off to watch things in case things fire up here. Link to comment Share on other sites More sharing options...
DaculaWeather Posted March 25, 2011 Share Posted March 25, 2011 FFC says around 1am - 7am Sunday. Link to comment Share on other sites More sharing options...
audioguy3107 Posted March 25, 2011 Share Posted March 25, 2011 FFC says around 1am - 7am Sunday. Judging by some of the models, seems that would be the most likely time for a squall line/cold front passage. I'm more worried about any discrete cells that form well ahead and move east across the warm front, especially as they interact with the wedge boundary further into N. Georgia. This setup really reminds me of March 2008, although I admit I don't remember the exact placement of all the players. Progged instability seems to be very similar. Link to comment Share on other sites More sharing options...
jrips27 Posted March 25, 2011 Share Posted March 25, 2011 Pretty pumped about this tomorrow. I think I might be a bit too far northeast for the biggest threat. Still any storms are nice in my opinion. Will be following it closely! Link to comment Share on other sites More sharing options...
eyewall Posted March 26, 2011 Share Posted March 26, 2011 UNfortunately it looks like I won't be able to chase this one out there. Looks like I have a long wait before any chance close by here . Link to comment Share on other sites More sharing options...
jrips27 Posted March 26, 2011 Share Posted March 26, 2011 UNfortunately it looks like I won't be able to chase this one out there. Looks like I have a long wait before any chance close by here . That sucks man. We will see how it pans out. Link to comment Share on other sites More sharing options...
eyewall Posted March 26, 2011 Share Posted March 26, 2011 That sucks man. We will see how it pans out. Definitely. I am almost tempted to go for sloppy seconds in SC/GA on Sunday just to see something. Link to comment Share on other sites More sharing options...
superjames1992 Posted March 26, 2011 Share Posted March 26, 2011 UNfortunately it looks like I won't be able to chase this one out there. Looks like I have a long wait before any chance close by here . I think we're going to be in a better position to chase snow than severe weather. Of course, at our respective doorsteps will fall a lovely, cold, bitter rain. Link to comment Share on other sites More sharing options...
jrips27 Posted March 26, 2011 Share Posted March 26, 2011 I'm almost positive we see a Moderate risk somewhere in MS/AL/GA. Could be some long-tracked tornadoes. Link to comment Share on other sites More sharing options...
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