andyhb Posted January 21, 2012 Share Posted January 21, 2012 SPC has issued a large 30% hatched area with a MDT risk possible once the day 1 comes out. This all points to the most potentially significant severe weather in some time across the CONUS. DAY 2 CONVECTIVE OUTLOOKNWS STORM PREDICTION CENTER NORMAN OK 1130 AM CST SAT JAN 21 2012 VALID 221200Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID-SOUTH/LOWER AND MIDDLE MS VALLEY TO OH/TN VALLEYS... ...SYNOPSIS... A PROGRESSIVE LARGE SCALE PATTERN WILL PREVAIL THROUGH SUNDAY OVER THE CONUS. AN UPPER TROUGH /AND ASSOCIATED STRONG MID-UPPER JET/ NOW OVER THE CONUS WEST COAST WILL REACH THE PLAINS EARLY SUNDAY...AND EVENTUALLY TAKE ON MORE OF A NEGATIVE TILT TOWARD THE MIDDLE/UPPER MS RIVER VALLEY AND MIDWEST SUNDAY NIGHT. THIS SYSTEM WILL BE A CONSIDERABLE FACTOR IN TERMS OF SEVERE CONVECTIVE POTENTIAL ESPECIALLY SUNDAY NIGHT/EARLY MONDAY. FARTHER WEST...A SECONDARY UPPER TROUGH/STRONG JET ALOFT WILL REACH THE WEST COAST BY EARLY MONDAY. ...ARKLATEX/OZARKS AND MID-SOUTH TO MS/TN RIVER VALLEYS... AN APPRECIABLE SEVERE EVENT IS POSSIBLE ACROSS THE REGION SUNDAY NIGHT/EARLY MONDAY...INCLUDING THE POTENTIAL FOR TORNADOES AND DAMAGING WINDS. AN UPGRADE TO A CATEGORICAL MODERATE RISK MAY BE WARRANTED IN SUBSEQUENT OUTLOOKS FOR PORTIONS OF THE REGION. GIVEN THE LARGE SCALE SCENARIO AS PREVIOUSLY DESCRIBED...AND THAT A RELATIVELY MOISTURE-RICH AIRMASS WILL ONLY BE SUPPRESSED TO THE GULF COAST REGION WITH THE DAY-1 FRONTAL PASSAGE...A RELATIVELY QUICK/QUALITY RETURN OF BOUNDARY LAYER MOISTURE IS ANTICIPATED ACROSS THE REGION ON SUNDAY AHEAD OF THE APPROACHING PLAINS UPPER TROUGH. THIS RELATIVELY MOIST/BROAD WARM SECTOR WILL BE TO THE EAST-SOUTHWARD OF THE PRIMARY SURFACE CYCLOGENESIS FROM THE SOUTH-CENTRAL PLAINS TO THE LOWER MO VALLEY AND EVENTUALLY THE LAKE MI VICINITY BY EARLY MONDAY. NEAR AN EASTWARD-ADVANCING DRY LINE AND /MORE SO/ PACIFIC FRONT...INITIAL DEEP CONVECTIVE DEVELOPMENT MAY OCCUR ACROSS PORTIONS OF THE ARKLATEX/MID-SOUTH AS EARLY AS LATE AFTERNOON /OR MORE LIKELY/ SUNDAY EVENING. MORE DISCRETE/POTENTIALLY SUPERCELLULAR DEVELOPMENT COULD ALSO OCCUR ACROSS THE WARM SECTOR ACROSS THE LOWER MS VALLEY AS THE BOUNDARY LAYER CONTINUALLY MOISTENS/CAPPING ALOFT ABATES. GIVEN MORE THAN ADEQUATE MOISTURE/DESTABILIZATION...A ROBUST WIND FIELD /HIGHLIGHTED BY 90-100 KT AROUND 500 MB AND 55-65 KT WITHIN THE LOWEST 1-2 KM/ WILL FAVOR HIGHLY ORGANIZED STORM MODES WITH ASSOCIATED SEVERE POTENTIAL SUNDAY NIGHT/EARLY EVENING...WITH AN ISOLATED STRONG TORNADO/WIND DAMAGE EPISODE PLAUSIBLE. CURRENT THINKING IS THAT A MULTI-FACETED STORM MODE SHOULD EVOLVE THROUGH SUNDAY EARLY/MID-EVENING...INCLUDING INITIAL SEMI-DISCRETE SUPERCELLS AHEAD OF WHAT WILL BE A TENDENCY FOR QUICK-CLUSTERING/LINEAR EVOLUTION IN CLOSER PROXIMITY TO THE ADVANCING PACIFIC COLD FRONT. A PREVALENT QUASI-LINEAR MODE/FAST EAST-NORTHEASTWARD MOVING SQUALL LINE IS LIKELY BY LATE SUNDAY NIGHT...ESPECIALLY FROM MS/AL INTO PORTIONS OF THE TN VALLEY/LOWER OH VALLEY. AS SUCH...THE SEVERE THREAT /IN AN ISOLATED SENSE AT THE VERY LEAST/ WILL LIKELY CONTINUE WELL THROUGH THE EARLY MORNING HOURS OF MONDAY. ...OH VALLEY... FARTHER NORTH...THE EXACT DEGREE OF LOW-LEVEL MOISTENING AND DESTABILIZATION IS INHERENTLY MORE QUESTIONABLE...ESPECIALLY GIVEN RECENT WINTER-TYPE PRECIPITATION ACROSS PORTIONS OF THE MIDWEST WHICH PARTIALLY COINCIDES WITH THE EXPECTED SURFACE LOW TRACK/BRUNT OF DPVA AS THE UPPER SYSTEM EVENTUALLY TAKES ON A MORE NEGATIVE TILT. THAT SAID...A ROBUST WIND FIELD/LATE NIGHT DEEPENING PHASE OF THE CYCLONE MAY CONTRIBUTE TO A RESPECTABLE THREAT FOR WIND DAMAGE/PERHAPS A FEW TORNADOES EVEN WHERE NEAR-SURFACE INSTABILITY IS SCANT ACROSS THE LOWER OH VALLEY. ..GUYER.. 01/21/2012 Link to comment Share on other sites More sharing options...
andyhb Posted January 21, 2012 Author Share Posted January 21, 2012 HWO from BMX: ANOTHER ROUND OF SEVERE THUNDERSTORMS IS POSSIBLE ACROSS PORTIONSOF CENTRAL ALABAMA...FROM AROUND 10 PM SUNDAY EVENING TO PERHAPS AS LATE AS 10 AM MONDAY MORNING. THE LATEST COMPUTER MODEL DATA SUGGESTS THAT THIS SEVERE THREAT MAY BE INCREASING...AND THE THREAT NOW ALSO INCLUDES TORNADOES. WHILE ANY PART OF CENTRAL ALABAMA MAY BE AFFECTED...THE AREA WITH THE GREATEST SEVERE WEATHER AND TORNADO THREAT IS FROM THE CITIES OF GEIGER...TUSCALOOSA... BIRMINGHAM...AND GADSDEN...NORTHWARD. JAN disc: BY TONIGHT...SHALLOW COOL AIR MASS HOLDS ACROSS THE CWFA WITH LOWS IN THE 40S NORTH TO 50S SOUTH. THE FRONT STALLS NEAR THE COASTAL AREAS BEFORE RETURNING NWD ON SUNDAY FROM MID MORNING TO MID AFTERNOON. A RAPID WARMING AND MOISTENING PROCESS SUNDAY AFTERNOON WILL LEAD INTO THE SECOND SYSTEM ON TRACK FOR SUNDAY NIGHT WHICH IS LOOKING MORE POTENT AND INCREASINGLY CAPABLE OF WIDESPREAD AND RATHER SIGNIFICANT SEVERE WEATHER. CURRENT GFS AND ECMWF MODELS IN LINE STRENGTH WISE WITH THIS SYSTEM WITH ONLY SLIGHTLY DIFFERENT TIMING...WE WILL COMPROMISE IN TIMING. AMPLIFIED UPPER LEVEL TROUGH SHOULD ROTATE IN NEGATIVELY-TILTED FOR THE LOWER MS VALLEY SUNDAY NIGHT WITH A DEEPENING SURFACE LOW(996MB) OVER MO. A LOW LEVEL JET OF 50 TO 60 KNOTS WILL USHERING GULF MOISTURE(850MB THETA E 325-330K) RAPIDLY N ALONG THE MS RIVER AND SURFACE DEWPOINTS JUMP BACK INTO THE L-M60S. MLCAPES OF 800-1200J/KG AND 0-3KM HELICITIES OF 300-400M*M/S*S AND AN IMPRESSIVE MID LEVEL DRY PUNCH OF 60-70KTS AT 700MB AND ANOTHER LEFT EXIT REGION OF A 200MB 130KT JET STREAK...ALL SET THE STAGE FOR OUR LOCAL CHECKLISTS TO INDICATE AT LEAST A MODERATE RISK CATEGORY FOR ABOUT THE NRN HALF OF OUR CWFA. THEN AS THE MAIN AXIS OF MOISTURE...LIFT...INSTABILITY AND WIND SHEAR ALL COME TOGETHER FROM ABOUT 5PM THROUGH 2AM ACROSS OUR REGION SUNDAY NIGHT...CONFIDENCE GROWING THAT WE WILL HAVE A SUBSTANTIAL SEVERE WEATHER EVENT. MAIN QUESTION MARK REMAINS STORM MODE BECAUSE THERE COULD BE ENOUGH OF A MID LEVEL CAP TO KEEP STORMS INITIATING ONLY IN A LINEAR MANNER. EVEN IN THIS CASE THOUGH... EMBEDDED SUPERCELLS AND TORNADOES WILL BE A CONCERN ALONG WITH THE HIGHER POTENTIAL FOR WIDESPREAD WIND DAMAGE. Small snippet from MEG: FOCUS FOR THIS AFTERNOONS FORECAST WILL CONCENTRATE ON THE TIMINGAND THREAT FOR SEVERE WEATHER SUNDAY LATE AFTERNOON THROUGH ABOUT 3 AM EARLY MONDAY MORNING. THE NEW NAM IS SHOWING JUST HOW INTENSE THE INSTABILITY COULD BE WHILE MATCHING UP WITH 40 TO 55 KNOTS OF BULK SHEAR. ROTATING STORMS ARE LOOKING MORE FAVORABLE AT THIS TIME. Link to comment Share on other sites More sharing options...
scoresman Posted January 21, 2012 Share Posted January 21, 2012 Another event in my back yard. Too bad it looks like most if not all of it will occur after sunset.... Link to comment Share on other sites More sharing options...
Ian Posted January 21, 2012 Share Posted January 21, 2012 looks like it could be a pretty big damaging tornado event based on newer models Link to comment Share on other sites More sharing options...
andyhb Posted January 21, 2012 Author Share Posted January 21, 2012 A SLIGHT RISK OF SEVERE WEATHER IS EXPECTED FROM LATE SUNDAYAFTERNOON...THROUGH EARLY MONDAY MORNING. A STRONG SPRING LIKE STORM WILL CROSS THE MIDSOUTH LATE SUNDAY AND SUNDAY NIGHT. WARM MOIST AIR WILL SURGE NORTHWARD DURING THE DAY COUPLED WITH A STRONG COLD FRONT BY THE EVENING HOURS. PORTIONS OF THE MIDSOUTH MAY BE UPGRADED TO A MODERATE RISK OF SEVERE WEATHER AS EARLY AS SUNDAY MORNING. THE MAIN THREATS ARE DAMAGING WINDS...LARGE HAIL...AND TORNADOES. THIS COULD BE THE FIRST APPRECIABLE OUTBREAK OF SEVERE WEATHER IN THE MIDSOUTH FOR 2012. THE BULK OF THE SEVERE WEATHER SHOULD OCCUR AFTER DARK...THEREFORE IT WILL BE IMPORTANT TO TAKE COVER IMMEDIATELY IN A SAFE LOCATION TO PROTECT YOURSELF IF A WARNING IS ISSUED. PERSONS ARE URGED TO REVIEW THEIR SEVERE WEATHER SAFETY PLANS NOW AND KNOW WHAT ACTIONS TO TAKE IF A WARNING IS ISSUED FOR YOUR LOCATION. Link to comment Share on other sites More sharing options...
Amped Posted January 21, 2012 Share Posted January 21, 2012 SPC sref is down. Twister data shows a low cape high shear event, which I could have guessed based on the time of year. Link to comment Share on other sites More sharing options...
andyhb Posted January 21, 2012 Author Share Posted January 21, 2012 I wouldn't say "low" cape per say, especially when looking at the NAM... Link to comment Share on other sites More sharing options...
andyhb Posted January 21, 2012 Author Share Posted January 21, 2012 Link to comment Share on other sites More sharing options...
SouthernNJ Posted January 22, 2012 Share Posted January 22, 2012 Moderate Risk has now been issued. Link to comment Share on other sites More sharing options...
Chicago Storm Posted January 22, 2012 Share Posted January 22, 2012 ..LOWER TO MID MS VALLEY/TN VALLEY A POWERFUL UPPER-LEVEL TROUGH OVER THE ROCKIES WILL MOVE EWD INTO THE GREAT PLAINS TODAY AND INTO THE MS VALLEY THIS EVENING. THE TROUGH WILL BECOME NEGATIVELY-TILTED AS AN UPPER-LEVEL LOW CLOSES OFF OVER THE UPPER MIDWEST. AHEAD OF THE SYSTEM...A 50 TO 70 KT LOW-LEVEL JET WILL EXPAND NWD ACROSS THE MID-MS VALLEY TODAY WITH STRONG MOISTURE ADVECTION TAKING PLACE IN THE LOWER MS VALLEY. SFC DEWPOINTS IN THE LOWER TO MID 60S F ARE FORECAST TO REACH AS FAR NORTH AS MEMPHIS TN BY LATE AFTERNOON WHERE THE NAM AND GFS DEVELOP A POCKET OF MODERATE INSTABILITY SSWWD ACROSS ERN AR. MODEL FORECASTS RAPIDLY INITIATE STORMS ALONG THE INSTABILITY AXIS AROUND 23/00Z. THESE STORMS SHOULD QUICKLY EXPAND IN COVERAGE AS A LINEAR MCS ORGANIZES AND MOVES EWD ACROSS THE TN VALLEY SUNDAY EVENING. AS THE UPPER-LEVEL TROUGH APPROACHES THE MID MS VALLEY LATE SUNDAY AFTERNOON...A CYCLONICALLY CURVED 70 TO 90 KT MID-LEVEL JET WILL CREATE A STRONG WIND FIELD FAVORABLE FOR SEVERE STORMS. INTERACTION BETWEEN THE MID-LEVEL AND LOW-LEVEL JETS WILL ENHANCE LOW-LEVEL SHEAR WITH TORNADIC SUPERCELLS POSSIBLE. THIS THREAT SHOULD BE GREATEST AS DISCRETE STORMS INITIATE IN ERN AR AND MOVE EWD INTO NW MS AND INTO THE MEMPHIS AREA EARLY THIS EVENING. FORECAST SOUNDINGS FOR MEMPHIS AT 03Z SHOW 0-3 KM STORM RELATIVE HELICITIES OF 400 TO 450 M2/S2 SUGGESTING A FEW STRONG TORNADOES MAY OCCUR WITH A LONG-TRACK TORNADO POSSIBLE. THE MORE DOMINANT SUPERCELLS MAY ALSO HAVE A THREAT FOR ISOLATED VERY LARGE HAIL BUT THIS THREAT APPEARS CONDITIONAL UPON THE DEVELOPMENT OF INTENSE DISCRETE SUPERCELLS. THE GREATER THREAT SHOULD BE FOR DAMAGING WIND GUSTS AS A LINE FORMS THIS EVENING AND MOVES EWD ACROSS WRN TO MIDDLE TN...NRN MS AND NRN AL. SOME WIND GUSTS OF GREATER THAN 70 KT APPEAR POSSIBLE DUE TO THE STRONG WIND FIELDS AND VERY FOCUSED LARGE-SCALE ASCENT. Link to comment Share on other sites More sharing options...
jaxjagman Posted January 22, 2012 Share Posted January 22, 2012 ..LOWER TO MID MS VALLEY/TN VALLEY A POWERFUL UPPER-LEVEL TROUGH OVER THE ROCKIES WILL MOVE EWD INTO THE GREAT PLAINS TODAY AND INTO THE MS VALLEY THIS EVENING. THE TROUGH WILL BECOME NEGATIVELY-TILTED AS AN UPPER-LEVEL LOW CLOSES OFF OVER THE UPPER MIDWEST. AHEAD OF THE SYSTEM...A 50 TO 70 KT LOW-LEVEL JET WILL EXPAND NWD ACROSS THE MID-MS VALLEY TODAY WITH STRONG MOISTURE ADVECTION TAKING PLACE IN THE LOWER MS VALLEY. SFC DEWPOINTS IN THE LOWER TO MID 60S F ARE FORECAST TO REACH AS FAR NORTH AS MEMPHIS TN BY LATE AFTERNOON WHERE THE NAM AND GFS DEVELOP A POCKET OF MODERATE INSTABILITY SSWWD ACROSS ERN AR. MODEL FORECASTS RAPIDLY INITIATE STORMS ALONG THE INSTABILITY AXIS AROUND 23/00Z. THESE STORMS SHOULD QUICKLY EXPAND IN COVERAGE AS A LINEAR MCS ORGANIZES AND MOVES EWD ACROSS THE TN VALLEY SUNDAY EVENING. AS THE UPPER-LEVEL TROUGH APPROACHES THE MID MS VALLEY LATE SUNDAY AFTERNOON...A CYCLONICALLY CURVED 70 TO 90 KT MID-LEVEL JET WILL CREATE A STRONG WIND FIELD FAVORABLE FOR SEVERE STORMS. INTERACTION BETWEEN THE MID-LEVEL AND LOW-LEVEL JETS WILL ENHANCE LOW-LEVEL SHEAR WITH TORNADIC SUPERCELLS POSSIBLE. THIS THREAT SHOULD BE GREATEST AS DISCRETE STORMS INITIATE IN ERN AR AND MOVE EWD INTO NW MS AND INTO THE MEMPHIS AREA EARLY THIS EVENING. FORECAST SOUNDINGS FOR MEMPHIS AT 03Z SHOW 0-3 KM STORM RELATIVE HELICITIES OF 400 TO 450 M2/S2 SUGGESTING A FEW STRONG TORNADOES MAY OCCUR WITH A LONG-TRACK TORNADO POSSIBLE. THE MORE DOMINANT SUPERCELLS MAY ALSO HAVE A THREAT FOR ISOLATED VERY LARGE HAIL BUT THIS THREAT APPEARS CONDITIONAL UPON THE DEVELOPMENT OF INTENSE DISCRETE SUPERCELLS. THE GREATER THREAT SHOULD BE FOR DAMAGING WIND GUSTS AS A LINE FORMS THIS EVENING AND MOVES EWD ACROSS WRN TO MIDDLE TN...NRN MS AND NRN AL. SOME WIND GUSTS OF GREATER THAN 70 KT APPEAR POSSIBLE DUE TO THE STRONG WIND FIELDS AND VERY FOCUSED LARGE-SCALE ASCENT. these colors don't even match up what so ever,i don't get it? Link to comment Share on other sites More sharing options...
beneficii Posted January 22, 2012 Share Posted January 22, 2012 these colors don't even match up what so ever,i don't get it? ??? The greatest tornado threat is progged to be E AR, SW TN, and N MS. Link to comment Share on other sites More sharing options...
jaxjagman Posted January 22, 2012 Share Posted January 22, 2012 ??? The greatest tornado threat is progged to be E AR, SW TN, and N MS. Havent seen this before.I guess the model just omit certain colors,it's still strange though Link to comment Share on other sites More sharing options...
JoMo Posted January 22, 2012 Share Posted January 22, 2012 Havent seen this before.I guess the model just omit certain colors,it's still strange though I don't get what you are saying about the colors? What's wrong with them? Link to comment Share on other sites More sharing options...
beneficii Posted January 22, 2012 Share Posted January 22, 2012 Havent seen this before.I guess the model just omit certain colors,it's still strange though Were you thinking of the color patterns used here? http://www.spc.noaa.gov/products/outlook/day1otlk.html Link to comment Share on other sites More sharing options...
Shawn Posted January 22, 2012 Share Posted January 22, 2012 Havent seen this before.I guess the model just omit certain colors,it's still strange though Basically the biggest area (white) is 2% or less. The smaller the circles go, the higher the risk. The answer key is on the bottom left of the map you posted. It's hatched with lines in the smaller circles because that's the area of greatest concern at 15%. EDIT: The color blue you see on the map isn't the 45% one. There are two shades of blue. The darker of that blue would be 45%. The blue depicted is "light" which means 5%. Link to comment Share on other sites More sharing options...
beneficii Posted January 22, 2012 Share Posted January 22, 2012 Basically the biggest area (white) is 2% or less. The smaller the circles go, the higher the risk. The answer key is on the bottom left of the map you posted. It's hatched with lines in the smallest circle because that's the area of greatest concern at 15%. Actually, the hatched area is 10% probability of EF2 or stronger tornadoes within 25 miles of a point. Link to comment Share on other sites More sharing options...
andyhb Posted January 22, 2012 Author Share Posted January 22, 2012 MEG is going to have a busy evening tomorrow. Link to comment Share on other sites More sharing options...
Shawn Posted January 22, 2012 Share Posted January 22, 2012 Actually, the hatched area is 10% probability of EF2 or stronger tornadoes within 25 miles of a point. Per SPC, yes. Thank you for clarifying that. EDIT: This is much easier to read and has been posted. You can read more details about it at http://www.spc.noaa.gov/products/outlook/ Link to comment Share on other sites More sharing options...
jaxjagman Posted January 22, 2012 Share Posted January 22, 2012 Basically the biggest area (white) is 2% or less. The smaller the circles go, the higher the risk. The answer key is on the bottom left of the map you posted. It's hatched with lines in the smaller circles because that's the area of greatest concern at 15%. EDIT: The color blue you see on the map isn't the 45% one. There are two shades of blue. The darker of that blue would be 45%. The blue depicted is "light" which means 5%. Thanks,that explains my confusion Link to comment Share on other sites More sharing options...
andyhb Posted January 22, 2012 Author Share Posted January 22, 2012 Sfc low is down to 988 mb per SPC mesoanalysis, which is significantly deeper than some of the models predicted. Link to comment Share on other sites More sharing options...
beneficii Posted January 22, 2012 Share Posted January 22, 2012 Sfc low is down to 988 mb per SPC mesoanalysis, which is significantly deeper than some of the models predicted. If you go to the 2-hour pressure change option, it'll say 987 hPa. This is a strong system. Link to comment Share on other sites More sharing options...
Shawn Posted January 22, 2012 Share Posted January 22, 2012 If you go to the 2-hour pressure change option, it'll say 987 hPa. This is a strong system. Link to comment Share on other sites More sharing options...
Stebo Posted January 22, 2012 Share Posted January 22, 2012 Sfc low is down to 988 mb per SPC mesoanalysis, which is significantly deeper than some of the models predicted. The models are playing catch up already, both the NAM/GFS 06Z runs are slower/stronger compared to 00Z runs. Link to comment Share on other sites More sharing options...
NavarreDon Posted January 22, 2012 Share Posted January 22, 2012 PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0358 AM CST SUN JAN 22 2012 ...SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF THE LOWER MISSISSIPPI...LOWER OHIO...AND TENNESSEE VALLEYS LATE THIS AFTERNOON THROUGH EARLY MONDAY... THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE DEVELOPMENT OF TORNADOES...WIDESPREAD DAMAGING WINDS...AND HAIL OVER PARTS OF THE LOWER MISSISSIPPI...LOWER OHIO...AND TENNESSEE VALLEYS LATE THIS AFTERNOON THROUGH EARLY MONDAY. THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE NORTHERN AND CENTRAL ALABAMA EASTERN AND SOUTHERN ARKANSAS SOUTHERN ILLINOIS SOUTHERN INDIANA WESTERN AND CENTRAL KENTUCKY SOUTHEASTERN MISSOURI NORTHERN AND CENTRAL MISSISSIPPI WESTERN AND MIDDLE TENNESSEE SURROUNDING THE GREATEST RISK AREA...SEVERE STORMS ARE ALSO POSSIBLE FROM THE CENTRAL GULF COAST NORTH AND NORTHEAST INTO PARTS OF MICHIGAN...OHIO...AND THE WESTERN SLOPES OF THE SOUTHERN AND CENTRAL APPALACHIANS. A POWERFUL JET STREAM DISTURBANCE NOW OVER THE SOUTHERN ROCKIES WILL MOVE RAPIDLY EASTWARD TODAY...REACHING THE EASTERN PORTIONS OF KANSAS AND OKLAHOMA BY EVENING. THE SYSTEM WILL CONTINUE EAST-NORTHEAST ACROSS THE MISSISSIPPI AND OHIO VALLEYS TONIGHT AND EARLY MONDAY...FURTHER INTENSIFYING IN THE PROCESS. IN ASSOCIATION WITH THE JET STREAM IMPULSE...A STRONG SURFACE LOW WILL TRACK EAST ACROSS KANSAS TODAY...AND THEN NORTHEAST ACROSS MISSOURI AND IOWA TONIGHT...BEFORE REACHING WISCONSIN EARLY MONDAY. AHEAD OF THE LOW...A BROAD CURRENT OF FAST SOUTHERLY WINDS WILL USHER UNSEASONABLY WARM AND MOIST AIR NORTHWARD ACROSS THE LOWER MISSISSIPPI...LOWER OHIO AND TENNESSEE VALLEYS. A COLD FRONT TRAILING SOUTH FROM THE LOW WILL SERVE AS A FOCUS FOR INTENSE THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON THROUGH TONIGHT OVER PARTS OF ILLINOIS...SOUTHEAST MISSOURI...ARKANSAS...AND LOUISIANA AS THE FRONT ENCOUNTERS THE INCREASINGLY WARM AND HUMID AIR. AS THE STORMS BUILD AND INTERACT WITH THE JET STREAM WINDS...SOME OF THEM LIKELY WILL BECOME LONG-LIVED SUPERCELLS...POSING A RISK FOR STRONG TORNADOES IN ADDITION TO DAMAGING WIND AND HAIL. THE TORNADO THREAT SHOULD BE GREATEST THIS EVENING AND EARLY TONIGHT OVER EASTERN ARKANSAS...NORTHERN MISSISSIPPI...AND WESTERN TENNESSEE. THE STORMS LIKELY WILL EVOLVE INTO AN EXTENSIVE LINE LATER TONIGHT...EXTENDING THE RISK FOR DAMAGING WIND AND POSSIBLE TORNADOES THROUGH DAWN MONDAY NORTHWARD AND EASTWARD TO THE WESTERN SLOPES OF THE SOUTHERN AND CENTRAL APPALACHIANS. Link to comment Share on other sites More sharing options...
DaculaWeather Posted January 22, 2012 Share Posted January 22, 2012 Link to comment Share on other sites More sharing options...
DaculaWeather Posted January 22, 2012 Share Posted January 22, 2012 Newest update: Link to comment Share on other sites More sharing options...
buckeyefan1 Posted January 22, 2012 Share Posted January 22, 2012 Looks to be a very active day, be careful out there se peeps DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0711 AM CST SUN JAN 22 2012 VALID 221300Z - 231200Z ...THERE IS A MDT RISK OF SVR TSTMS ...THERE IS A MDT RISK OF SVR TSTMS FROM PARTS OF AR...MS...AND AL NWD THROUGH SE MO...WRN TN...AND WRN KY INTO SRN IL AND SRN IND...... ...THERE IS A SLGT RISK OF SVR TSTMS ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK AREA FROM THE CNTRL GULF CST NEWD INTO PARTS OF OH...... ...SYNOPSIS... ...A REGIONAL SEVERE WEATHER EVENT LIKELY TO OCCUR FROM THE LWR MS VLY NEWD INTO PARTS OF THE MID MS...TN...AND LWR OH VLYS THIS EVE THROUGH EARLY MON... POTENT UPR TROUGH NOW OVER THE CNTRL/SRN RCKYS WILL MOVE E INTO ERN KS/OK THIS EVE...BEFORE ASSUMING A NEGATIVE TILT AND ACCELERATING ENE ACROSS THE MID MS...LWR OH...AND TN VLYS TNGT AND EARLY MON. ASSOCIATED SFC LOW WILL TRACK E ACROSS KS TODAY...BEFORE TURNING NE ACROSS NRN MO AND IA TNGT...AND INTO WI EARLY MON. AHEAD OF THE LOW AND TROUGH...SATELLITE AND VWP DATA ATTM SHOW BROAD 50+ KT SSWLY LLJ EXPANDING NWD ACROSS ERN PARTS OF THE PLNS. THIS JET WILL EXPAND FARTHER E ACROSS THE MID MS AND TN VLYS TODAY...WITH STRONG MOISTURE ADVECTION OCCURRING ATOP SHALLOW SURFACE-BASED LAYER OF COLD AIR OVER THE REGION. STRONG TSTMS SHOULD FORM LATE THIS AFTN OR EARLY THIS EVE FROM IL SSW INTO PARTS OF MO/AR AND LA...ALONG LEAD COLD FRONT TRAILING SWD FROM THE LOW. GIVEN VERY STRONG WIND FIELD ASSOCIATED WITH THE UPR TROUGH AND INCREASINGLY WARM/MOIST LOW LVL ENVIRONMENT ALONG/AHEAD OF FRONT...THE STORMS WILL HAVE THE POTENTIAL TO PRODUCE STRONG TORNADOES IN ADDITION TO DMGG WIND AND HAIL AS THEY MOVE/DEVELOP E AND NE ACROSS THE TN AND LWR OH VLYS THROUGH 12Z MON. ...LWR MS VLY NWD AND EWD INTO THE TN AND LWR OH VLYS LATE TODAY THROUGH EARLY MON... SFC DEWPOINTS IN THE LOW TO MID 60S F SHOULD EXTEND NWD TO THE MO BOOTHEEL BY LATE TODAY GIVEN STRONG/PERSISTENT LOW LVL WAA/MOISTURE TRANSPORT. COUPLED WITH MODEST SFC HEATING...THIS SHOULD RESULT IN AN AXIS OF MODERATE INSTABILITY THAT WILL REACH SSWWD ACROSS ERN/SRN AR INTO MS/LA. TSTMS SHOULD FORM ALONG THE NW EDGE OF THIS INSTABILITY AXIS LATE THIS AFTN...AND SHOULD QUICKLY EXPAND IN COVERAGE NWD AND SWD AS LEAD SFC COLD FRONT OVERTAKES MOIST AXIS AND CONTINUES EWD. WITH TIME...AN EXTENSIVE SQLN SHOULD EVOLVE FROM THE LWR OH VLY SSW INTO AR/NW MS/LA. 70 TO 90 KT MID LVL JET OVERSPREADING REGION SHOULD SUPPORT AT LEAST A FEW LONGER-LIVED SUPERCELLS. LOW LVL SRH SHOULD MAXIMIZE OVER PARTS OF AR...SE MO...WRN TN AND NRN MS...ON SRN FRINGE OF RETREATING SHALLOW COOL AIR LAYER. GIVEN COMPARATIVELY GREATER SFC-BASED INSTABILITY IN THIS REGION...POTENTIAL WILL EXIST FOR STRONG TORNADOES....ESPECIALLY THROUGH EARLY EVENING. TORNADOES WILL ALSO BE POSSIBLE THROUGH EARLY MON E/SE INTO PARTS OF ERN MS AND AL AS EXISTING STORMS AND STRENGTHENING WIND FIELD ENCOUNTER MORE SLOWLY-RETREATING PART OF WEDGE AIR MASS IN THAT REGION. FARTHER N...THE MORE SIGNIFICANT SVR THREAT SHOULD BE DMGG WINDS AS THE DEVELOPING SQLN AND TURBULENT MIXING ENCOURAGE DOWNWARD TRANSPORT OF STRONG LWR TROPOSPHERIC FLOW TO THE SFC...EVEN IN REGIONS OF NEAR-ZERO SFC-BASED CAPE. THIS THREAT MAY CONTINUE...AT LEAST ON A SPORADIC BASIS...NWD AND EWD INTO PARTS OF OH AND TO THE WRN SLOPES OF THE CNTRL/SRN APPALACHIANS EARLY MON. IN THE MEAN TIME...A CONDITIONAL RISK WILL EXIST FOR A FEW STRONG STORMS OVER PARTS OF AL AND WRN GA TODAY...WHERE SFC HEATING AND ASCENT WITH WEAK LEAD UPR IMPULSE MAY SUPPORT SCTD CONVECTIVE DEVELOPMENT. ENVIRONMENT MAY PROVE FAVORABLY MOIST...UNSTABLE...AND SUFFICIENTLY SHEARED TO POSE A THREAT FOR AN ISOLD TORNADO. ..CORFIDI/SMITH.. 01/22/2012 Link to comment Share on other sites More sharing options...
IWC Posted January 22, 2012 Share Posted January 22, 2012 Newest update: Steve ,The work your doing is great! I wish I had more time to spend on the weather I enjoy reading the work guys like you and robert and the rest of the gang put in. I have my weather station and would like to set it up on your list sometime. When I can find the time. Link to comment Share on other sites More sharing options...
DaculaWeather Posted January 22, 2012 Share Posted January 22, 2012 FXUS64 KBMX 221735 AFDBMX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BIRMINGHAM AL 1135 AM CST SUN JAN 22 2012 ...SEVERE STORMS INCLUDING TORNADOES POSSIBLE TONIGHT... Link to comment Share on other sites More sharing options...
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