andyhb Posted December 22, 2011 Share Posted December 22, 2011 Day 1 Slight Risk, 5% Tornado Probs. across LA/MS/AL/GA/Western FL Panhandle. DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1155 PM CST WED DEC 21 2011 VALID 221200Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF THE LOWER MS VALLEY AND DEEP SOUTH... ...SYNOPSIS... A SHORT WAVE TROUGH CENTERED ACROSS WRN TX INTO COAHUILA WILL TRACK E/NEWD ACROSS TX THIS MORNING BEFORE DAMPENING AS IT ACCELERATES NEWD TOWARDS THE LOWER OH VALLEY BY EARLY EVENING. AT THE SURFACE...A WEAK CYCLONE WILL TRACK NEWD ALONG A FRONTAL ZONE OFF THE TX COAST...ACROSS THE LOWER MS VALLEY INTO NRN AL...AND EVENTUALLY INTO THE MID-ATLANTIC THROUGH EARLY FRI. ...LOWER MS VALLEY/DEEP SOUTH... A SWATH OF RAIN/EMBEDDED TSTMS WITHIN AN ENVIRONMENT OF WEAK ELEVATED BUOYANCY WILL BE ONGOING AT 12Z/THU ACROSS ERN TX INTO PARTS OF THE LOWER MS VALLEY. THIS EXPANSIVE PRECIPITATION SHIELD SHOULD RETARD THE NWD RETREAT OF THE FRONT...WITH THIS BOUNDARY EXPECTED TO BISECT LA/MS INTO NRN AL BY 18Z. STRENGTHENING LOW-LEVEL SWLYS COUPLED WITH STRONGLY FORCED ASCENT THROUGH MID-LEVEL DCVA/LOW-LEVEL WAA SHOULD PROMOTE ACTIVITY DEVELOPING E/NEWD ALONG THE FRONTAL ZONE. DESPITE MEAGER INSTABILITY...STRONG LOW/DEEP-LAYER SHEAR SHOULD RESULT IN ORGANIZED LINE SEGMENTS PROMOTING A RISK FOR DAMAGING WINDS AND PERHAPS A BRIEF TORNADO. FARTHER E/SE...A SEPARATE AREA OF MORE DISCRETE TSTMS SHOULD FORM WITHIN THE OPEN WARM SECTOR ACROSS THE CNTRL GULF COAST. THIS SCENARIO IS INFERRED BY OPERATIONAL GUIDANCE WITHIN AN AXIS OF LOW-LEVEL CONFLUENCE AND DEPICTED BY CONVECTION-ALLOWING WRF-NMM AND HRRR GUIDANCE. DESPITE POTENTIALLY LIMITED SURFACE HEATING...65-70 F SURFACE DEW POINTS SHOULD BE SUFFICIENT FOR MLCAPE TO INCREASE TO BETWEEN 400-800 J/KG. 0-1 KM SRH AROUND 150-250 M2/S2 WILL SUPPORT A FEW SUPERCELLS CAPABLE OF PRODUCING TORNADOES/DAMAGING WINDS...PEAKING IN THE LATE MORNING TO MID-AFTERNOON. LOW-LEVEL MOISTURE AND INSTABILITY WILL WANE WITH NEWD EXTENT TOWARDS THE SRN APPALACHIANS...WITH A DIMINISHING SEVERE THREAT EXPECTED AFTER DARK AS THE SHORT WAVE IMPULSE WEAKENS AND BECOMES INCREASINGLY DIVORCED FROM THE WARM SECTOR. ..GRAMS/ROGERS.. 12/22/2011 Link to comment Share on other sites More sharing options...
LovingGulfLows Posted December 22, 2011 Share Posted December 22, 2011 You should change the title to December 22nd . Link to comment Share on other sites More sharing options...
andyhb Posted December 22, 2011 Author Share Posted December 22, 2011 Yeah, realized that after I typed it lol... Link to comment Share on other sites More sharing options...
SmokeEater Posted December 22, 2011 Share Posted December 22, 2011 Tornado Watch out for LA/MS, until 1pm. Link to comment Share on other sites More sharing options...
Amos83 Posted December 22, 2011 Share Posted December 22, 2011 Severe hatch just extended to cover a good area of the western carolinas. Forecast Discussion SPC AC 221257 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0657 AM CST THU DEC 22 2011 VALID 221300Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE LWR MS VLY TO THE SRN APPALACHIANS... ...SYNOPSIS... E TX SHORTWAVE TROUGH EXPECTED TO SHEAR RAPIDLY NE THIS PERIOD AS SYSTEM IS ABSORBED WITHIN BROAD BELT OF WSW FLOW OVER THE CNTRL AND ERN U.S...DOWNSTREAM FROM PERSISTENT SPLIT OVER THE GRT BASIN/RCKYS. THE TROUGH SHOULD REACH THE LWR OH VLY THIS EVE...AND THE MID ATLANTIC STATES EARLY FRI. AT LWR LVLS...SFC WAVE NOW NEAR BTR EXPECTED TO TRACK NEWD ALONG WARM FRONT REFORMING NWD INTO SRN MS AND CNTRL AL ATTM. THE LOW SHOULD REACH THE MS/AL BORDER BY MIDDAY...AND ERN TN/WRN NC BY EVE...BEFORE CONTINUING RAPIDLY ENE TO OFF THE NJ CST EARLY FRI. ...LWR MS VLY TO SRN APPALACHIANS TODAY... A SSW-NNE SQLN HAS EVOLVED OVER CNTRL LA AND WRN MS...ON LEADING EDGE OF BROAD SWATH OF RAIN/ELEVATED TSTMS ASSOCIATED WITH EJECTION OF TX SHORTWAVE TROUGH. E OF THE SQLN...LOW LVL AIR MASS RECOVERY CONTINUES...WITH SHALLOW WSW-ENE WARM FRONT NOW INLAND ACROSS SE LA/SRN MS. THE BOUNDARY SHOULD MOVE/REFORM NWD THROUGH MIDDAY. SEASONABLY WARM AND MOIST AIR /SFC DEW POINTS AOA THE MID 60S F AND PW AROUND 1.50 INCHES/ WILL SPREAD INTO MUCH OF AL AND GA IN ITS WAKE. STRENGTHENING LOW LVL SSW FLOW/MOISTURE TRANSPORT AND STRONG FORCING FOR ASCENT /DCVA AND WELL-DEFINED JET ENTRANCE CIRCULATION ASSOCIATED WITH DOWNSTREAM UPR RIDGE/ SHOULD MAINTAIN/PROMOTE STORM DEVELOPMENT E/NEWD ALONG WARM FRONT INTO THE SRN APPALACHIANS...AND PERHAPS SSW ALONG DEVELOPING COLD FRONT INTO THE NRN GULF. WHILE LOW TO MID LVL LAPSE RATES WILL REMAIN WEAK...SUFFICIENT BUOYANCY SHOULD REMAIN PRESENT TO SUPPORT SUSTAINED STORMS IN LEWPS/LINE SEGMENTS. THESE MAY YIELD LOCALLY DMGG WIND AND PERHAPS ISOLD TORNADOES GIVEN 50 KT SW 700 MB FLOW AND 60+ KT 0-6 KM SHEAR. FARTHER E/SE...A SEPARATE AREA OF MORE DISCRETE STORMS MAY FORM IN EXISTING LOW LVL CONFLUENCE ZONE/AXIS OF RICHER MOISTER /PER SATELLITE-DERIVED PW DATA/ EXTENDING FROM THE N CNTRL GULF INTO FAR SE LA...SRN MS...AL...THE WRN FL PANHANDLE...AND GA. EVEN MODEST SFC HEATING SHOULD BOOST SBCAPE TO ABOVE 500 J/KG GIVEN SFC DEW POINTS NEAR 70 F. WITH 0-1 KM SRH AROUND 150-250 M2/S2...A FEW SUPERCELLS CAPABLE OF TORNADOES/DMGG WIND MAY OCCUR...ESPECIALLY LATE THIS MORNING THROUGH LATE THIS AFTN. AREA OF GREATEST FORCING FOR ASCENT/STRONGEST FLOW WILL MOVE BEYOND LOW LVL MOISTURE AND INSTABILITY LATER TODAY AND TNGT AS UPR SYSTEM DEAMPLIFIES ENEWD. THIS SHOULD RESULT IN A DIMINISHING...ALTHOUGH STILL NON-ZERO...SVR THREAT AFTER SUNSET. Link to comment Share on other sites More sharing options...
nrgjeff Posted December 22, 2011 Share Posted December 22, 2011 If it is not going to snow, let's do severe. Why not? Situation looks marginal and I like the SPC keeping it low-key. At the risk of soundlng like a broken record, I like I-20 south better. Warm front has made into North Georgia, but as of 9:00 Central trails southwest through Alabama to the sfc low in east Miss. I expect convergence to sharpen up along I-20, perhaps taking North GA out of severe. Plenty of heavy rain and lightning though. Lots of low clouds to work through from the I-20 corridor south. It has to come together during daylight also due to the rapidly departing jet streak and upper support. Until then the right entrance/rear quad will be over the area in question. Within the mess of heavy rain and thunderstorms a few sups may pop out ahead of the line. Otherwise look for the isolated spinner along the line. I-10 corridor is not quite under the best part of the jet streak, but the coastal front lurks. Can’t count that out for isolated either. This is far from a chase day, but the most exciting weather we’ve seen in a while. Left exit/front will just enhance heavy rain over Tenn. What a surprise! I'm having trouble seeing severe in NC but rain is in the cards. Link to comment Share on other sites More sharing options...
SouthernNJ Posted December 22, 2011 Share Posted December 22, 2011 The TOR storm west of Leakesville MS has the best structure to it so far today. Link to comment Share on other sites More sharing options...
andyhb Posted December 22, 2011 Author Share Posted December 22, 2011 Nice couplet on that storm. Tornado warning continued. Link to comment Share on other sites More sharing options...
on_wx Posted December 22, 2011 Share Posted December 22, 2011 Nice couplet on that storm. Tornado warning continued. I have a scanner open for Greene County MS police... but it doesn't appear to be working. http://www.radioreference.com/apps/audio/?ctid=1417 Link to comment Share on other sites More sharing options...
SmokeEater Posted December 22, 2011 Share Posted December 22, 2011 100 KT couplet right on the AL/MS state line, near State Line, MS. Link to comment Share on other sites More sharing options...
andyhb Posted December 22, 2011 Author Share Posted December 22, 2011 SRV has had strong velocities for the past several scans, Adair just said a LLDV at 107 kts. Link to comment Share on other sites More sharing options...
andyhb Posted December 22, 2011 Author Share Posted December 22, 2011 MESOSCALE DISCUSSION 2390 NWS STORM PREDICTION CENTER NORMAN OK 1122 AM CST THU DEC 22 2011 AREAS AFFECTED...SERN MS / SWRN AL CONCERNING...TORNADO WATCH 899... VALID 221722Z - 221815Z THE SEVERE WEATHER THREAT FOR TORNADO WATCH 899 CONTINUES. TORNADO RISK WILL LOCALLY BE MAXIMIZED AS/IF STORMS MATURE INTO SUPERCELLS AS THEY MOVE NEWD FROM SERN MS/FAR SWRN AL INTO SWRN AL. SUPERCELLS THAT DEVELOP AHEAD OF APPROACHING SQUALL LINE WILL POSE THE GREATEST RISK FOR TORNADO/S. MESOSCALE ANALYSIS PLACES AN INCREASINGLY MOIST/DESTABILIZING WARM SECTOR ACROSS SERN MS INTO THE SWRN QUARTER OF AL. TEMPS IN THE LOW 70S WITH UPPER 60S DEWPOINTS WILL OFFSET A MARGINAL LAPSE RATE PROFILE AS STORMS DEVELOP/MOVE NEWD THE NEXT FEW HOURS. KMOB VAD SHOWS 350 MS/S2 0-1 KM SRH WITHIN A STRONGLY SUPPORTIVE SUPERCELL WIND PROFILE. GIVEN MODESTLY IMPROVING THERMODYNAMIC SETUP COINCIDENT WITH THE DIURNAL CYCLE...EXPECTING A LOCALIZED HIGHER THREAT FOR A TORNADO OR TWO /PERHAPS SIGNIFICANT/ WITH ANY LONG-LIVED SUPERCELLS THAT DEVELOP/PERSIST AHEAD OF ADVANCING SQUALL LINE THE NEXT FEW HOURS ACROSS SWRN AL. ..SMITH.. 12/22/2011 Link to comment Share on other sites More sharing options...
BillT Posted December 22, 2011 Share Posted December 22, 2011 we are in the watch area in walker county alabama, but our winds have shifted coming from the north, temp at 60 and slowing dropping and dewpoint dropped from 60 to 53.6 in less than an hour, dont see how we can now have anything severe here. Link to comment Share on other sites More sharing options...
andyhb Posted December 22, 2011 Author Share Posted December 22, 2011 Tornado warning Tuscaloosa...not good... Link to comment Share on other sites More sharing options...
on_wx Posted December 22, 2011 Share Posted December 22, 2011 James Spann isn't impressed.. http://www.ustream.tv/channel/ABC-33-40-Main#utm_campaign=synclickback&source=http://www.abc3340.com/global/category.asp?c=206394/&medium=520983 Link to comment Share on other sites More sharing options...
The Colonel Posted December 22, 2011 Share Posted December 22, 2011 I'll report anything that comes near here. Local news is not too keen on this, however is stating that I-20/59 corridor will be the battle line today as storms continue to mature and head into the warmer air. It's very sticky outside right now. Kinda gross...even if it was May or April Link to comment Share on other sites More sharing options...
BillT Posted December 22, 2011 Share Posted December 22, 2011 temp down to 54.5, dp down to 48.4 and we are about 50 miles north of tuscaloosa as a crow flies. Link to comment Share on other sites More sharing options...
jrips27 Posted December 22, 2011 Share Posted December 22, 2011 THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A * TORNADO WARNING FOR... SOUTHEASTERN BIBB COUNTY IN ALABAMA... NORTHWESTERN CHILTON COUNTY IN ALABAMA... SOUTHERN SHELBY COUNTY IN ALABAMA... * UNTIL 145 PM CST * AT 1253 PM CST...THE NATIONAL WEATHER SERVICE INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED 5 MILES SOUTH OF BRENT...AND MOVING NORTHEAST AT 45 MPH. Link to comment Share on other sites More sharing options...
jrips27 Posted December 22, 2011 Share Posted December 22, 2011 Interesting... 18Z SURFACE MESOANALYSIS PLACES A 1011 MB LOW INVOF BHM WITH A STATIONARY FRONT EXTENDING NEWD INTO FAR NWRN GA AND INTO THE NC SMOKY MTNS. THE AIRMASS AHEAD OF THE LOW AND S OF THE BOUNDARY CONTINUES TO DESTABILIZE DUE IN PART TO A NWD FLUX OF RICHER GULF MOISTURE MOVING N/NEWD INTO THE AREA. AN AREA OF MAXIMUM SURFACE PRESSURE FALLS /3.5 MB PER 2 HRS/ EXISTS IMMEDIATELY AHEAD OF THE LOW INTO FAR NWRN GA. KFFC VAD HAS SHOWN 1 KM FLOW INCREASE FROM 25-40 KTS THE PAST 3 HRS. THIS IS INDICATIVE OF THE LOW LEVEL JET MIGRATING NEWD TOWARDS THE SPINE OF THE APPALACHIANS FROM THE NRN GULF COAST AS THE PRIMARY MID-LEVEL VORTICITY MAXIMUM MOVES FROM THE LOWER MS RIVER VALLEY TO THE LOWER OH VALLEY BY THIS EVENING. DESPITE RATHER MARGINAL LAPSE RATES...GRADUAL THETA-E INCREASE WITH TIME WILL SUPPORT 250-750 J/KG SBCAPE...SUPPORTIVE OF ROBUST UPDRAFTS. WITH THE BACKGROUND WIND FIELD FEATURING 300-600 M2/S2 EFFECTIVE SRH PER RUC FORECAST SOUNDINGS...THIS WILL BE MORE THAN EASILY SUPPORTIVE OF SEVERAL ORGANIZED AND ROTATING...LINEARLY ORIENTED STORMS. AN ISOLD TORNADO THREAT...IN ADDITION TO WIND DAMAGE...WILL EXIST WITH ANY MESOVORTICIES AND EMBEDDED MESOCYCLONES. Link to comment Share on other sites More sharing options...
WeatherNC Posted December 22, 2011 Share Posted December 22, 2011 Interesting... Thanks for posting this, hot off the press, N GA crew, basically the northern half of the state, heads up, may get a little dicey as the afternoon/evening progresses. Link to comment Share on other sites More sharing options...
DaculaWeather Posted December 22, 2011 Share Posted December 22, 2011 Link to comment Share on other sites More sharing options...
jrips27 Posted December 22, 2011 Share Posted December 22, 2011 Going to the movies til 6ish, hope anything that comes this way holds off until I return... 68o and muggy. Link to comment Share on other sites More sharing options...
DaculaWeather Posted December 22, 2011 Share Posted December 22, 2011 Tornado near the BMX radar Link to comment Share on other sites More sharing options...
toxictwister00 Posted December 22, 2011 Share Posted December 22, 2011 Seems a little odd to me that the chances of severe weather is just as good if not better considering we have been doses of moderate to heavy rain today. I kinda figured that may hamper the severe threat here. Link to comment Share on other sites More sharing options...
WeatherNC Posted December 22, 2011 Share Posted December 22, 2011 Seems a little odd to me that the chances of severe weather is just as good if not better considering we have been doses of moderate to heavy rain today. I kinda figured that may hamper the severe threat here. Just going off of SPC meso composite indices and what I am seeing with regard to lower levels, NW quadrant of GA greatest risk, just inside the triple point as the slp begins to deepen and track along the southern Apps. http://www.spc.noaa.gov/exper/mesoanalysis/new/viewsector.php?sector=18 Link to comment Share on other sites More sharing options...
DixieBlizzard Posted December 22, 2011 Share Posted December 22, 2011 Glad I am home early today. Today had a severe weather day "feel" to it. Link to comment Share on other sites More sharing options...
Psalm 148:8 Posted December 22, 2011 Share Posted December 22, 2011 Dacula, ck your inbox...tried to pm you and it wouldn't go....got a dinner to go to tonite....could you give me approximate time frame the main line of storms will approach the AL/GA border. Link to comment Share on other sites More sharing options...
toxictwister00 Posted December 22, 2011 Share Posted December 22, 2011 Just going off of SPC meso composite indices and what I am seeing with regard to lower levels, NW quadrant of GA greatest risk, just inside the triple point as the slp begins to deepen and track along the southern Apps. http://www.spc.noaa....r.php?sector=18 Ah, I see. I actually saw Dr. Forbes mention not too long ago on TWC how the low was providing extra lift and instability. Link to comment Share on other sites More sharing options...
WeatherNC Posted December 22, 2011 Share Posted December 22, 2011 1km Eastern US Vis, valid 3pm EST Link to comment Share on other sites More sharing options...
CandymanColumbusGA Posted December 22, 2011 Share Posted December 22, 2011 New Watch for much of North and Central Georgia. Certainly have some strong storms about to enter my Alabama Counties... Let the games begin... Sure feels like severe weather out there. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.