MESOSCALE DISCUSSION NWS STORM PREDICTION CENTER

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2567
   NWS STORM PREDICTION CENTER NORMAN OK
   0626 AM CST THU DEC 15 2005
   
   AREAS AFFECTED...NRN GA/CAROLINA PIEDMONT/CNTRL VA/ERN WV
   
   CONCERNING...FREEZING RAIN
   
   VALID 151226Z - 151830Z
   
   ...SIGNIFICANT FREEZING RAIN EVENT IS ONGOING THIS MORNING FROM NE
   GA INTO THE CAROLINA PIEDMONT. MODERATE RATES OF FZRA UP TO 0.10
   INCHES PER HOUR WILL LIKELY CONTINUE THROUGH THE MORNING...
   
   LATEST SFC ANALYSIS SHOWS SFC LOW IN SRN AL WITH WARM/COASTAL FRONT
   EXTENDING SEWD ACROSS NRN FL AND THEN CLOSELY HUGGING THE CAROLINA
   COASTS. WEDGE OF SUBFREEZING AIR EXTENDS FROM NEAR ATLANTA NEWD
   ACROSS THE PIEDMONT INTO ERN WV/VA. STRONG ASCENT WILL CONTINUE
   AHEAD OF UPPER IMPULSE NOW OVER THE LOWER MS VALLEY. THIS LARGE
   SCALE LIFT COMBINED WITH SIGNIFICANT LOW LEVEL WARM ADVECTION /VAD
   WIND DATA 50-60KT AT 850MB/ WILL MAINTAIN LARGE PRECIPITATION
   SHIELD. MUCH OF THE PRECIPITATION WILL BE FREEZING RAIN WITHIN THE
   COLD AIR DAMMING REGION EAST OF THE MTNS.
   
   SFC LOW PRESSURE WILL MOVE INTO WRN PORTIONS OF GA LATER THIS
   MORNING AS COASTAL/WARM FRONT MOVES INLAND. BASED ON CURRENT
   TRENDS...HEAVIEST AXIS OF FREEZING RAIN OVER THE NEXT FEW HOURS WILL
   EXTEND FROM ATHENS TO CHARLOTTE TO EAST OF ROANOKE. RAINFALL
   ACCUMULATIONS OF 0.20-0.30 INCHES HAVE BEEN OBSERVED IN NRN GA
   WITHIN THE LAST 3-6 HOURS...SO SIGNIFICANT ICING ACCUMULATIONS ARE
   LIKELY IN SOME AREAS.
   
   12Z SOUNDINGS FROM RNK/GSO SHOW STRONG WAA PROFILE WITH SHALLOW WARM
   LAYERS NEAR OR ABOVE 0 DEG C. WARM NOSE IS MORE PRONOUNCED AND
   DEEPER AT GSO...WHICH SUPPORTS A PROLONGED PERIOD OF FZRA. A MIX OF
   SLEET/SNOW WILL OCCUR IN THE HIGHER ELEVATIONS.
   
   ..TAYLOR.. 12/15/2005
   
   
   ATTN...WFO...AKQ...LWX...RAH...RNK...RLX...CAE...GSP...MRX...FFC...
   
   33568257 33658405 35078430 36818203 38267984 38797794
   38327710 37467756 35937858 33818123

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2568
   NWS STORM PREDICTION CENTER NORMAN OK
   0737 AM CST THU DEC 15 2005
   
   AREAS AFFECTED...PORTIONS FL PANHANDLE AND COASTAL BEND...SWRN GA.
   
   CONCERNING...TORNADO WATCH 897...
   
   VALID 151337Z - 151430Z
   
   SEVERE POTENTIAL REMAINS ALONG/AHEAD OF PRIMARY CONVECTIVE
   BAND...INDICATED AT 13Z FROM NRN WALTON COUNTY FL SSWWD ACROSS VPS
   AREA OVER OPEN GULF.
   
   SFC MESOANALYSIS INDICATES COMBINED MARINE/WARM FRONT AND OUTFLOW
   BOUNDARY FROM OLD MCS...NEAR LINE FROM 60 W PIE...15 S AAF...40 S
   VPS.  TSTMS -- INCLUDING A FEW SUPERCELLS...HAVE DEVELOPED ALONG AND
   S OF THIS FRONT THEN WEAKENED AS THEY EITHER MOVE PROGRESSIVELY
   FARTHER N OF FRONTAL ZONE OR BECOME ABSORBED BY MAIN CONVECTIVE
   BAND.  THIS TREND SHOULD CONTINUE FOR ANY ADDITIONAL ACTIVITY THAT
   DEVELOPS IN WARM SECTOR.  HOWEVER...AS REGIME SHIFTS EWD TOWARD
   SEWD-ORIENTED COASTLINE THROUGH 15Z...TORNADO THREAT WILL INCREASE
   FROM PFN AREA SEWD TO VICINITY AAF WHERE WARM FRONT -- AND
   ASSOCIATED NEARLY SFC-BASED PARCELS -- IMPINGE ON COASTLINE.
   THEREAFTER...AIR MASS IS EXPECTED TO DESTABILIZE OVER TLH REGION AND
   FL COASTAL BEND...AS COMBINATION OF DIURNAL HEATING AND WAA RELATED
   TO VEERING SFC FLOW ACT TO BOOST SFC THETAE AND INTRODUCE AT LEAST
   MARGINAL SBCAPES 300-800 J/KG. SBCAPES APCHG 500 J/KG ALREADY ARE
   EVIDENT N OF WARM FRONT OVER NARROW AREA BETWEEN MAIN CONVECTIVE
   BAND AND PFN...WHERE 0-1 KM SRH 300-600 J/KG IS EVIDENT BASED ON
   MODIFIED TLH RAOB...VWP DATA AND RUC SOUNDINGS.
   
   ..EDWARDS.. 12/15/2005
   
   
   ATTN...WFO...JAX...TAE...
   
   29378319 29348520 30008652 30468633 30858609 31008484
   30998289 30348319

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2569
   NWS STORM PREDICTION CENTER NORMAN OK
   1000 AM CST THU DEC 15 2005
   
   AREAS AFFECTED...NE INDIANA/SE MI/NW OH
   
   CONCERNING...HEAVY SNOW
   
   VALID 151600Z - 152000Z
   
   SNOW IS EXPECTED TO INCREASE THROUGH EARLY AFTERNOON FROM FAR NE
   INDIANA/NW OH INTO SE/THUMB OF MI. SNOW RATES WILL REACH 1 IN/HR ON
   A LOCALIZED BASIS.
   
   EAST OF STACKED LOW CENTERED ALONG THE MN/WI BORDER...OBSERVATIONAL
   TRENDS FEATURE AXIS OF INCREASING SNOW ACROSS NE INDIANA/WRN OH/FAR
   SE MI...PART OF BROADER BAROCLINIC LEAF STRUCTURE SEEN IN WATER
   VAPOR/INFRARED IMAGERY. THIS ACTIVITY IS FOCUSED IN GENERAL SSW-NNE
   ORIENTATION ALIGNED WITH MID LEVEL FRONTOGENETICAL FORCING BETWEEN
   600-700 MB. SIMILAR TO OBSERVATIONAL TRENDS...09Z SREF AND LATEST
   RUC/WRF GUIDANCE SUGGESTS SNOW SHOULD CONTINUE TO INCREASE FROM FAR
   NE INDIANA/NW OH INTO SOUTHEAST/THUMB VICINITY OF MI THROUGH EARLY
   AFTERNOON. ALTHOUGH LOW LEVEL TEMPERATURES PROFILES ARE
   MARGINAL...AMPLE PRECIPITATION RATES SHOULD BE SUPPORTIVE OF
   MDT/OCNLY HEAVY WET SNOW. SNOW RATES MAY REACH 1 IN/HR ON A
   LOCALIZED BASIS INTO MID AFTERNOON.
   
   ..GUYER.. 12/15/2005
   
   
   ATTN...WFO...CLE...ILN...DTX...APX...IWX...GRR...IND...
   
   44538346 43738261 41298274 40408345 40298480 40818556
   42338507

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2570
   NWS STORM PREDICTION CENTER NORMAN OK
   1105 AM CST THU DEC 15 2005
   
   AREAS AFFECTED...ERN FL PANHANDLE AND FAR SWRN/SRN GA
   
   CONCERNING...TORNADO WATCH 897...
   
   VALID 151705Z - 151800Z
   
   PARAMETERS REMAIN FAVORABLE FOR TORNADOES ACROSS VALID PARTS OF WW
   897 FROM THE ERN HALF OF FL PANHANDLE INTO FAR SWRN/SRN GA.
   GREATEST TORNADO THREAT SHOULD REMAIN ALONG/JUST INLAND OF THE FL
   COAST.
   
   16Z SURFACE ANALYSIS CONTINUED TO SHOW A MESO-LOW OVER THE CENTRAL
   FL PANHANDLE AT THE INTERSECTION OF THE COLD FRONT/SQUALL LINE AND A
   WEDGE FRONT WHICH EXTENDED FROM THIS LOW ACROSS SRN GA TO JUST S OF
   SAV.  A WARM FRONT EXTENDED FROM THE MESO-LOW SEWD JUST N OF AAF AND
   THEN OFFSHORE OVER THE NERN GULF.  HIGHER THETA-E AIR MASS EXISTS S
   OF THIS WARM FRONT WITH SURFACE DEWPOINTS IN THE MID-UPPER 60S.
   REGIONAL RADARS INDICATED A BROKEN LINE OF DISCRETE STORMS EXTENDING
   FROM THE MESO-LOW SWD TO OFFSHORE OVER THE GULF.  STRONGER ATTENDANT
   SHEAR COUPLETS WERE LOCATED WITH ACTIVITY AROUND THE AAF AREA AND
   SWD OFFSHORE.  THESE STORMS WILL CONTINUE TO POSE THE GREATEST RISK
   FOR TORNADOES AS THIS ACTIVITY INGESTS THE RICHER BOUNDARY LAYER
   MOISTURE...WHERE 0-3 KM SRH VALUES EXCEED 600 M2/S2.  15Z RUC
   SUGGESTS THE WARM FRONT SHOULD MOVE INLAND ALONG TAYLOR COUNTY BY
   18Z...INCREASING THE POTENTIAL FOR SURFACE BASED STORMS AND
   ATTENDANT TORNADO/DAMAGING WIND THREAT ACROSS THIS PART OF WW.
   
   LATEST TRENDS IN LIGHTNING DATA SUGGEST THE STRONGEST ACTIVITY IS
   ALONG AND OFFSHORE THE ERN FL PANHANDLE COAST. REGIONAL RADARS ALSO
   INDICATED A SIMILAR TREND FOR STORMS TO BE WEAKER AND/OR WEAKEN AS
   THEY MOVE NORTH OF THE WARM FRONT.
   
   ..PETERS.. 12/15/2005
   
   
   ATTN...WFO...JAX...TAE...
   
   29558514 31058493 31038262 29668353 29468504

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2571
   NWS STORM PREDICTION CENTER NORMAN OK
   1219 PM CST THU DEC 15 2005
   
   AREAS AFFECTED...ERN FL PANHANDLE AND FAR SRN GA
   
   CONCERNING...TORNADO WATCH 897...
   
   VALID 151819Z - 151915Z
   
   TORNADO/DAMAGING WIND THREATS EXPECTED TO CONTINUE THROUGH 19-21Z...
   PRIMARILY ALONG THE COASTAL AREAS OF VALID PART OF WW 897.
   THUS...ERN PARTS OF WW /TAYLOR...LAFAYETTE AND DIXIE COUNTIES/ MAY
   NEED TO BE LOCALLY EXTENDED FOR 1-2 HOURS.
   
   REGIONAL RADARS/LIGHTNING DATA INDICATED STRONGEST ACTIVITY WAS
   LOCATED FROM SE OF TLH OVER ERN LEON/WAKULLA COUNTIES AND SWD
   OFFSHORE OVER THE NERN GULF OF MEXICO. STRONG SHEAR COUPLETS WERE
   ASSOCIATED WITH OFFSHORE DISCRETE STORMS EXTENDING FROM 50 E AAF TO
   60 SSE AAF.  AIR MASS DOWNSTREAM OVER THE FL BIG BEND REGION HAS
   BEEN SLOWLY MODIFYING WITH SURFACE DEWPOINTS INTO THE MID-UPPER 50S.
   CLOUDINESS ASSOCIATED WITH BROKEN LINE OF STORMS SPREADING
   DOWNSTREAM ACROSS ERN PARTS OF WW 897 AND THE REST OF NRN FL/SRN GA
   IS LIMITING OVERALL SURFACE HEATING/DESTABILIZATION.  THUS...GIVEN
   MORE STABLE AIR MASS INLAND OVER NRN FL...NEW WW IS NOT WARRANTED.
   HOWEVER...SERN PART OF WW MAY NEED TO BE LOCALLY EXTENDED AS
   STRONGER OFFSHORE STORMS POSE A THREAT TO THESE COUNTIES BETWEEN
   19-21Z.
   
   ..PETERS.. 12/15/2005
   
   
   ATTN...WFO...TBW...JAX...TAE...
   
   29458482 29918453 31028410 31038258 29378297 29038348

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2572
   NWS STORM PREDICTION CENTER NORMAN OK
   1243 PM CST THU DEC 15 2005
   
   AREAS AFFECTED...MUCH OF PA/FAR SRN NY/WRN AND CNTRL MD/ERN WV/WRN
   VA/WRN NC
   
   CONCERNING...WINTER MIXED PRECIPITATION
   
   VALID 151843Z - 152345Z
   
   PREDOMINANT FREEZING RAIN/SLEET IS EXPECTED THIS AFTERNOON FROM FAR
   NE OH INTO WRN/SCNTRL PA AND WRN/CNTRL MD. PRECIPITATION RATES
   SHOULD INCREASE ACROSS CNTRL/ERN PA THROUGH 21Z-0ZZ...WITH SNOW
   PREDOMINANT PRECIP TYPE. FURTHER SOUTH...FREEZING RAIN WILL CONTINUE
   FOR THE NEXT SEVERAL HOURS ALONG THE SPINE OF THE CNTRL
   APPALACHIANS...WITH A GRADUAL CHANGE OVER TO ALL RAIN OCCURRING FROM
   SOUTH TO NORTH THIS AFTERNOON.
   
   EXTENSIVE PRECIPITATION SHIELD WILL CONTINUE TO SPREAD E/NE FROM THE
   OHIO VALLEY/MID ATLANTIC INTO THE NE STATES THIS
   AFTERNOON...ATTRIBUTABLE TO AMPLE UVVS VIA JUXTAPOSITION OF
   DPVA/UPPER JET ENHANCED LIFT AND LOW LEVEL WAA/MOISTURE TRANSPORT
   REGIME.
   
   IN ACCORDANCE WITH OBSERVATIONAL TRENDS...15Z RUC SOUNDINGS AND 09Z
   SREF CONSENSUS/WINTER ALGORITHMS SUGGEST RELATIVELY LONGEST
   DURATION/GREATEST PROBABILITY FOR FREEZING RAIN AND/OR SLEET THROUGH
   21Z-00Z SHOULD OCCUR ACROSS WRN/SCNTRL PA...WRN/CNTRL MD...AND ERN
   WV/NW VA. IN THESE AREAS...ENCROACHING 800-850 MB LEVEL WARM LAYER
   /AS SAMPLED BY 12Z ROANOKE RAOB/ WILL BE FAVORABLE FOR FREEZING RAIN
   AND/OR SLEET WHERE SUB-FREEZING NEAR-SFC TEMPS ARE
   MAINTAINED...WHICH IS ESPECIALLY LIKELY IN VALLEY AREAS.
   
   WITH SOUTHWARD EXTENT...OWING TO STRONG WARM AIR ADVECTION
   REGIME...INITIAL COLD WEDGE WILL GRADUALLY BE OVERCOME ALONG/EAST OF
   THE CNTRL APPALACHIANS THROUGH THE AFTERNOON. PREDOMINANT
   PRECIP-TYPE IS EXPECTED TO GRADUALLY CHANGE FROM FREEZING RAIN TO
   RAIN ACCORDINGLY FROM SOUTH TO NORTH ACROSS THE NW NC/VA
   APPALACHIANS.
   
   ..GUYER.. 12/15/2005
   
   
   ATTN...WFO...PHI...BGM...BUF...CTP...LWX...RNK...PBZ...RLX...CLE...GSP...MRX...
   
   39847594 38947734 36697977 35838135 36068174 36598178
   37628113 38897964 40268013 41098099 41888047 42387805
   41237558

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2573
   NWS STORM PREDICTION CENTER NORMAN OK
   0123 PM CST THU DEC 15 2005
   
   AREAS AFFECTED...NE LOWER MI
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION
   
   VALID 151923Z - 152300Z
   
   OCNLY MODERATE SNOW WILL DEVELOP/SPREAD FROM THE THUMB AREA INTO NE
   LOWER MI THROUGH MID AFTERNOON. RATES COULD REACH 1 IN/HR WITHIN THE
   HEAVIER BANDS FOR A FEW HOURS DURATION BETWEEN 20Z-00Z.
   
   VOLUMETRIC RADAR TRENDS SUGGESTS AREAS OF MODERATE SNOW...ONGOING
   EARLY THIS AFTERNOON ACROSS SE LOWER MI...SHOULD CONTINUE TO SPREAD
   N/NE INTO THE NE PORTION OF LOWER MI REMAINDER OF THE AFTERNOON.
   SIMILAR TO OBSERVATIONAL TRENDS...SHORT-TERM RUC/4KM WRF GUIDANCE
   SUGGESTS THIS WILL GENERALLY OCCUR IN AREAS ALONG/EAST OF INTERSTATE
   75. ATTRIBUTABLE TO AMPLE UVVS/SATURATED FAVORABLE DENDRITIC GROWTH
   ZONE PER 18Z RUC SOUNDINGS...SNOW RATES COULD LOCALLY REACH 1 IN/HR
   FOR A COUPLE HOURS DURATION.
   
   ..GUYER.. 12/15/2005
   
   
   ATTN...WFO...DTX...APX...
   
   45528411 45258321 44588303 43998290 43488319 43498410
   43758437 44668453

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2574
   NWS STORM PREDICTION CENTER NORMAN OK
   0446 PM CST THU DEC 15 2005
   
   AREAS AFFECTED...WRN FL PENINSULA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 152246Z - 160015Z
   
   POTENTIAL FOR AN ISOLATED TORNADO OR LOCALLY STRONG WINDS WILL EXIST
   ACROSS DISCUSSION AREA THIS EVENING.  OVERALL SEVERE THREAT APPEARS
   QUITE LIMITED AND A WW IS NOT ANTICIPATED.
   
   AS OF 2235Z...TAMPA RADAR INDICATED A PRE-FRONTAL BAND OF TSTMS OFF
   THE WRN FL PENINSULA WITH THE MOST INTENSE ACTIVITY FROM 45 NW OF
   PIE TO 60 W PIE.  LOCAL AIR MASS ALONG THE COAST IS MOIST AND
   MODERATELY UNSTABLE WITH MUCAPES OF AROUND 1000 J/KG.
   ADDITIONALLY...AMBIENT SHEAR PROFILES REMAIN SUPPORTIVE OF ORGANIZED
   STORMS /SUPERCELLS/ WITH EFFECTIVE BULK SHEARS OF 35-40 KTS AND 0-1
   KM SRH OF 200-250 M2/S2. 
   
   POTENTIAL FOR AN ISOLATED TORNADO OR LOCALLY DAMAGING WIND GUST WILL
   EXIST WITH THE MOST INTENSE STORMS AS THEY APPROACH THE COAST.
   HOWEVER...IT APPEARS THAT THE ABSENCE OF ANY APPRECIABLE LARGE-SCALE
   FORCING AND DEEP FRONTAL CONVERGENCE SHOULD TEND TO LIMIT THE
   OVERALL SEVERE WEATHER THREAT...ESPECIALLY AS THE BOUNDARY-LAYER
   COOLS LATER THIS EVENING.
   
   ..MEAD.. 12/15/2005
   
   
   ATTN...WFO...TBW...JAX...
   
   29008292 29378266 29388221 28708209 28268225 28048264
   28288295

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2575
   NWS STORM PREDICTION CENTER NORMAN OK
   0718 PM CST THU DEC 15 2005
   
   AREAS AFFECTED...SRN AND CNTRL NY/MUCH OF PA/WRN CT/NRN NJ/MD/FAR
   NRN VA/WV PANHANDLE
   
   CONCERNING...WINTER MIXED PRECIPITATION
   
   VALID 160118Z - 160545Z
   
   PRIMARILY FREEZING RAIN...WITH POTENTIAL FOR ICE
   ACCUMULATIONS...WILL CONTINUE TO TRANSITION NEWD ACROSS CNTRL/ERN
   PA...NRN NJ...INTO SRN/CNTRL NY AND WRN CT THIS EVENING. ACROSS WRN
   PA/WRN NY...A CHANGE OVER TO ALL SNOW IS EXPECTED THIS
   EVENING...WITH MDT/LOCALLY HEAVY SNOW DEVELOPING BY LATE
   EVENING/OVERNIGHT. FURTHER SOUTH...INITIAL FREEZING RAIN SHOULD
   CHANGE OVER TO RAIN ACROSS NRN VA/MUCH OF MD/SE PA/MOST OF NJ PRIOR
   TO 06Z.
   
   WITH BROAD NEGATIVE TILT TROUGH CENTERED OVER THE UPPER MISSISSIPPI
   VALLEY...VORTICITY MAX AND STRONG MID/UPPER JET CONTINUES TO RACE
   EWD TOWARD THE MID ATLANTIC/NORTHEAST STATES WITHIN BASE OF UPPER
   TROUGH. ACCORDINGLY...BROAD/DEEP FORCING FOR ASCENT IS CONTRIBUTING
   TO NEWD TRANSITION OF BROAD PRECIPITATION SHIELD INTO THE NORTHEAST
   STATES.
   
   AS SEEN IN THE 00Z WASHINGTON-DULLES RAOB...NWD EXTRAPOLATION OF
   ELEVATED MELTING LAYER WILL REMAIN SUPPORTIVE OF FREEZING RAIN AS
   PRIMARY PRECIP-TYPE ACROSS MUCH OF CNTRL/ERN PA AND NRN NJ INTO
   SRN/CNTRL NY AND WRN CT MUCH OF THE EVENING...WHERE WEDGE OF SHALLOW
   COLD AIR WILL BE MAINTAINED. SOME SLEET/SNOW WILL BE POSSIBLE AS
   WELL.
   
   FURTHER WEST...00Z PITTSBURG AND 00Z BUFFALO RAOBS FEATURE A 1-2C
   WARM LAYER NEAR 850 MB...STILL AT LEAST MARGINALLY SUPPORTIVE OF
   FREEZING RAIN/SOME SLEET. HOWEVER...WITH NOCTURNAL/DYNAMIC COOLING
   AND EVENTUAL COLD ADVECTION...21Z RUC GUIDANCE SUGGESTS A GRADUAL
   CHANGE OVER TO ALL SNOW SHOULD OCCUR ACROSS MUCH OF WRN PA/WRN NY BY
   LATE EVENING...WITH MDT/LOCALLY HEAVY SNOW PREVALENT INTO THE
   OVERNIGHT. SNOW RATES MAY REACH 1 IN/HR IN THESE AREAS BY 06Z.
   
   ..GUYER.. 12/16/2005
   
   
   ATTN...WFO...BOX...OKX...ALY...PHI...BGM...BUF...CTP...LWX...PBZ...RLX...CLE...
   
   43007437 41607284 41177380 40127503 39637663 39227774
   38567885 38737931 39677952 40097994 41568027 43177865
   43397632

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2576
   NWS STORM PREDICTION CENTER NORMAN OK
   1247 AM CST FRI DEC 16 2005
   
   AREAS AFFECTED...MUCH OF NEW ENGLAND/NRN APPALACHIANS
   
   CONCERNING...WINTER MIXED PRECIPITATION
   
   VALID 160647Z - 161215Z
   
   A MIX OF FREEZING RAIN/SLEET AND SNOW WILL DEVELOP ACROSS MUCH OF
   NEW ENGLAND OVERNIGHT. FREEZING RAIN WILL CHANGEOVER TO MODERATE TO
   HEAVY SNOW /HRLY RATES UP TO 1 INCH/ ACROSS PORTIONS OF CENTRAL/NRN
   PA INTO WRN/NRN NY...WITH FREEZING RAIN CHANGING OVER TO RAIN OVER
   FAR NRN NJ/NERN PA...THE LOWER HUDSON RIVER VALLEY AND MUCH OF CT
   THROUGH 12Z. HOURLY FREEING RAIN/SLEET RATES AROUND 0.10 INCH WILL
   BE COMMON ACROSS PORTIONS OF THE MIDDLE HUDSON RIVER VALLEY OF
   ECENTRAL NY AND WRN PORTIONS OF MA/FAR SRN VT/SRN NH...LEADING TO
   THE POTENTIAL FOR SIGNIFICANT SLEET AND ICING IN THESE AREAS THROUGH
   12Z.
   
   STRONG LOW LEVEL WAA WILL CONTINUE IN ADVANCE OF POTENT UPPER TROUGH
   MOVING THROUGH THE OHIO VALLEY. AT THE SURFACE...THE TREND OF A
   SLOWLY LIFTING SURFACE 32 DEG F LINE WILL CONTINUE OVERNIGHT AS A
   SURFACE LOW PRESSURE CENTERED OVER NEAR BWI AT 05Z LIFTS TOWARDS NYC
   BY 12Z. THEREFORE...NRN NJ...NERN PA...THE LOWER HUDSON RIVER VALLEY
   AND MUCH OF CT WILL SEE A CHANGEOVER FROM FREEZING PRECIP TO RAIN
   THROUGH 12Z. FURTHER NORTH...THE STRENGTH OF THE WAA AND GRADUAL
   SHRINKING OF THE ELEVATED WARM LAYER DEPTH DUE TO ASCENT WILL
   SUPPORT A MIX OF MODERATE TO OCCASIONALLY HEAVY FREEZING RAIN AND
   SLEET ACROSS MUCH OF ECENTRAL/NERN NY...VT/NH AND MA THROUGH 12Z.
   
   FURTHER WEST...LOW LEVEL CAA WAS COMMENCING PER VWP DATA AT PBZ. IN
   ADDITION...MID LEVEL FRONTOGENESIS WILL CONTINUE TO INTENSIFY IN THE
   700-600 MB LAYER SUPPORTING DENDRITIC SNOW GROWTH. THESE TWO WILL
   COMBINE TO AID IN A CHANGEOVER OF P-TYPE FROM FREEZING RAIN TO
   MOD-HVY SNOW OVER NCENTRAL PA NWD INTO WRN/NRN NY...ESPECIALLY
   DURING THE 08-12Z TIME FRAME.
   
   ..CROSBIE.. 12/16/2005
   
   
   ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...BUF...CTP...PBZ...
   
   44387148 43317068 42237116 41737201 41157332 41117459
   41077533 40937637 40587783 41147903 43077776 44837533
   44907298

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2577
   NWS STORM PREDICTION CENTER NORMAN OK
   0554 AM CST FRI DEC 16 2005
   
   AREAS AFFECTED...NERN NY...VT...NH...ME...NWRN MA
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION
   
   VALID 161154Z - 161700Z
   
   ...WINTER STORM PRODUCING AREAS OF ICE AND SNOW ACROSS THE
   NORTHEAST...
   
   FZRA WILL CREATE HAZARDOUS ICING FROM PARTS OF ERN NY... MA...SRN
   VT/NH...AND SWRN ME THIS MORNING. MDT TO HVY SN WILL FALL FROM
   CNTRL/NERN NY...AND ALONG THE CANADIAN BORDER FROM VT/NH TO INTERIOR
   MAINE. A BROAD TRANSITION ZONE OF SN...PL...AND FZRA WILL CONTINUE
   FROM CNTRL VT/NH TO MAINE THIS MORNING BEFORE CHANGING BACK TO SN BY
   AFTERNOON.
   
   AN INTENSE AND FAST-MOVING MID/UPPER LEVEL IMPULSE WAS ROTATING
   THROUGH THE ERN PERIPHERY OF A LARGE CLOSED LOW OVER WI THIS
   MORNING. DPVA ASSOCIATED WITH THE IMPULSE/JET HAS INDUCED SURFACE
   CYCLOGENESIS ALONG COASTAL BAROCLINIC ZONE VICINITY OF NJ. VERY
   TIGHT PRESSURE GRADIENT BETWEEN THE DEEPENING SECONDARY LOW AND A
   STRONG SURFACE HIGH OVER SRN QUEBEC WAS CONTRIBUTING TO PRONOUNCED
   INFLUX OF ATLANTIC MOISTURE NWWD AND INLAND ATOP SURFACE-BASED COLD
   DOME FROM ERN NY ACROSS NRN NEW ENGLAND.
   
   MID/UPPER LEVEL DRYING WAS DEVELOPING NEWD ACROSS VT/NH EARLY THIS
   MORNING BASED ON RECENT SATELLITE AND RADAR TRENDS. THIS WILL RESULT
   IN LOWER PCPN RATES IN THE SHORT TERM ACROSS THESE AREAS. WRF AND
   ENSEMBLE MEAN QPF WERE INDICATING ONE PCPN MAX ASSOCIATED WITH LIFT
   NEAR THE SURFACE LOW/BAROCLINIC ZONE...AND ANOTHER PCPN MAX FROM
   NERN NY TO SRN QUEBEC. AREAS IN THE SRN ZONE OF HEAVIER PCPN... FROM
   SERN NY ACROSS MA AND INTO SRN NH AND MAINE...MAY EXPERIENCE A
   PERIOD OF HVY ICING THIS MORNING AS WARMER AIR ALOFT CONTINUES TO
   SPREAD INLAND OVER THE SUB-FREEZING AIR AT THE SURFACE. SN WILL
   CHANGE TO A PERIOD OF FZRA IN THESE AREAS. THIS HAS ALREADY HAPPENED
   OVER SWRN MA...AND IS EXPECTED TO DEVELOP NEWD ACROSS SRN NH AND ME
   OVER THE NEXT FEW HOURS.
   
   FARTHER NORTH...SECONDARY PCPN MAXIMUM...FROM NERN NY ACROSS SRN
   QUEBEC...NRN VT/NH...AND INTERIOR ME...WILL LIKELY BE PRIMARILY IN
   THE FORM OF SN. INTENSE QG FORCING FOR ASCENT WILL CONTINUE TO PIVOT
   ENEWD FROM CNTRL/NERN NY THIS MORNING...AND ACROSS NRN NEW ENGLAND
   TO INTERIOR ME THROUGH THIS AFTERNOON. DYNAMIC COOLING IN THE LOW TO
   MID LEVELS WILL OFFSET WARM ADVECTION AND...COUPLED WITH INFLUX OF
   MOISTURE INTO THIS REGION...SUPPORT MDT TO HVY SN ON THE NRN EDGE OF
   THE PCPN TRANSITION ZONE. SN WILL TAPER OFF AND END FROM WEST TO
   EAST AS THE STRONGER UPPER FORCING MOVES ACROSS THESE AREAS THROUGH
   THE DAY.
   
   ..CARBIN.. 12/16/2005
   
   
   ATTN...WFO...CAR...GYX...BOX...BTV...ALY...BGM...BUF...
   
   46297016 45717074 45447138 45327257 45147396 44837539
   44267584 43177599 42847534 42817408 42127365 42057269
   42447120 42887082 43477058 44136923 45856858 46386920

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2578
   NWS STORM PREDICTION CENTER NORMAN OK
   1245 PM CST FRI DEC 16 2005
   
   AREAS AFFECTED...NRN VT/NH/MUCH OF ME
   
   CONCERNING...HEAVY SNOW
   
   VALID 161845Z - 162245Z
   
   ...SNOW WILL BE INCREASING IN INTENSITY ACROSS MUCH OF ME THIS
   AFTN...WITH RATES OF 1 TO 2 INCHES PER HOUR. MODERATE TO HEAVY SNOW
   WILL BE DIMINISHING ACROSS VT/NH WITHIN 1-3 HOURS...
   
   LATEST SFC ANALYSIS SHOWS RAPIDLY FALLING SFC PRESSURE /2-3MB PER
   HOUR OFFSHORE/ WITH LOW NOW NEAR BEDFORD. SYSTEM IS QUICKLY LIFTING
   NORTHEAST WITH DRIER AIR APPROACHING FROM THE SW PER WV LOOPS.
   COMPOSITE RADAR IMAGERY DEPICTS ENHANCED REFLECTIVITY RETURNS ACROSS
   SRN ME NEAR PORTLAND. RECENT SFC OBSERVATIONS AT KDAW /DAWSON/
   INDICATED HEAVY RAIN...WITH HEAVY SNOW NOW AT KIZG /FRYEBERG/...AS
   THIS MORE INTENSE PRECIPITATION MOVES BY.
   
   THERMAL PROFILES SUPPORT ALL SNOW...EXCEPT NEAR THE COASTAL AREAS
   WHERE RAIN WILL OCCUR. SNOW RATES WILL BE ENHANCED BOTH BY STRONG
   FRONTOGENESIS THROUGH A DEEP LAYER AND A SATURATED DENDRITIC
   ZONE...WHICH FORECAST SOUNDINGS SUGGEST WILL BE MAINTAINED TIL AT
   LEAST 21Z AROUND KBGR AND THROUGH 00Z NEAR KCAR.
   
   HEAVY SNOW NOW ONGOING ACROSS NRN PORTIONS OF VT/NH WILL END WITHIN
   A COUPLE HOURS. BUT IT APPEARS MODERATE TO HEAVY SNOW WILL CONTINUE
   ACROSS MUCH OF ME THROUGH THE AFTN.
   
   ..TAYLOR.. 12/16/2005
   
   
   ATTN...WFO...CAR...GYX...BOX...BTV...
   
   46537078 47446915 47086764 46066784 44886871 43067142
   43337229 44167251 44997261

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2579
   NWS STORM PREDICTION CENTER NORMAN OK
   0214 AM CST SUN DEC 18 2005
   
   AREAS AFFECTED...CA SIERRA NEVADA MOUNTAINS
   
   CONCERNING...HEAVY SNOW
   
   VALID 180814Z - 181415Z
   
   HEAVY WET SNOW IS EXPECTED TO OVERSPREAD THE SIERRA RANGE IN THE
   NEXT SEVERAL HOURS AS MOIST PACIFIC STORM SYSTEM MOVES INLAND.
   SNOWFALL RATES AOA 6000 FEET COULD EXCEED 2 INCHES PER HOUR THIS
   MORNING.
   
   OVER THE NEXT SEVERAL HOURS...PRECIPITATION RATES WILL CONTINUE TO
   INCREASE AND SPREAD INLAND FROM THE COAST AND ACROSS THE CNTRL
   VALLEY OF CA AS POTENT PACIFIC PERTURBATION MOVES EAST ACROSS THE
   NCNTRL CA COAST. OBSERVED RAINFALL RATES NEAR THE COAST WERE ALREADY
   IN THE RANGE OF 0.10 TO 0.25 INCHES PER HOUR WITHIN WARM AIR
   ADVECTION REGIME AHEAD OF THE STRONGER DYNAMIC FORCING. /REF
   NFDSPENES WMO HEADER TXUS20/.
   
   INTENSIFYING UPSLOPE FLOW AND DYNAMIC FORCING WITH THE MID/UPPER
   LEVEL IMPULSE/WIND MAX...ALONG WITH ENHANCED MOISTURE TRANSPORT
   ACCOMPANYING +1 INCH PW PLUME...WILL LEAD TO EXCESSIVE SNOWFALL
   RATES DEVELOPING ACROSS THE HIGHER ELEVATIONS THROUGH 12Z. WHILE
   SNOW LEVELS MAY INITIALLY CLIMB ABOVE 6000 FEET...FREEZING LEVELS
   WILL BEGIN TO FALL LATER THIS MORNING AS ADIABATIC COOLING WITHIN
   THE UPPER TROUGH AXIS SPREADS ACROSS THE AREA. WITH POTENTIAL FOR
   EMBEDDED CONVECTION...AND DECENT AGREEMENT IN LATEST SHORT-TERM QPF
   GUIDANCE FROM NAM AND RUC MODELS...SNOWFALL RATES OF 2-4 INCHES PER
   HOUR APPEAR LIKELY NEAR AND SOUTH OF THE TAHOE AREA BEFORE 12Z.
   WINDS ALSO INCREASING TO NEAR 50KT LATER THIS MORNING WILL PRODUCE
   DRIFTING SNOW AND WHITE-OUT CONDITIONS.
   
   ..CARBIN.. 12/18/2005
   
   
   ATTN...WFO...VEF...REV...HNX...STO...
   
   37021850 36771865 37371945 37972000 38232022 38682029
   39242058 39532070 39762078 40232140 40502156 40502133
   40442108 40292076 40112059 39902037 39672017 38932008
   37431870

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2580
   NWS STORM PREDICTION CENTER NORMAN OK
   1255 PM CST SUN DEC 18 2005
   
   AREAS AFFECTED...CNTRL AND ERN ORE/SIERRA/NRN NV
   
   CONCERNING...HEAVY SNOW
   
   VALID 181855Z - 190100Z
   
   ...MODERATE TO HEAVY SNOW WILL CONTINUE ACROSS THE NRN GREAT BASIN
   THROUGH AFTN...WITH SNOW SPREADING INTO THE ERN SLOPES OF THE
   CASCADES WITHIN A FEW HOURS. SNOW RATES ABOVE 4000 FEET MAY BE IN
   THE 2-3 INCH PER HOUR RANGE...
   
   LATEST IR SATELLITE IMAGERY SHOWS INCREASING MOISTURE/CLOUDS MOVING
   ACROSS SRN ID/ORE WITH SOME COOLING CLOUD TOPS NOTED. ENHANCED BAND
   OF CLOUDS SEEMS TO BE ASSOCIATED WITH DEFORMATION BAND NEAR 700MB.
   HEAVIEST SNOW CURRENTLY OVER NRN PORTIONS OF NV FROM LOL/WMC/EKO.
   MEANWHILE...SNOW HAS CHANGED OVER TO RAIN IN THE TAHOE/RENO
   AREA...SUGGESTING FROM THE SFC OBSERVATIONS THAT THE FREEZING LEVEL
   HAS RISEN ABOVE 6000 FEET.
   
   BAND OF SNOW IS EXPECTED TO INCREASE FROM DESCHUTES CO ORE INTO SW
   ID AND NW UT...ASSOCIATED WITH FRONTOGENETIC FORCING WITHIN THE
   750-650 MB LAYER AND UPWARD MOTION DUE TO VORTICITY ADVECTION. THIS
   IS SUPPORTED BY THE ETA/RUC/GFS. SNOW RATES MAY RANGE FROM 1 TO 2
   INCHES PER HOUR. SOME FZRA HAS BEEN OBSERVED NORTH OF MEDFORD
   EARLIER...BUT MOST LOCATIONS HAVE TEMPS ABOVE FREEZING NOW.
   EXCEPTION MAY BE IN VALLEY LOCATIONS WHERE STRONG INVERSION IS
   HOLDING DOWN TEMPS. HEAVY SNOW WILL ALSO CONTINUE IN THE HIGHER
   ELEVATIONS OF THE SIERRA
   
   ..TAYLOR.. 12/18/2005
   
   
   ATTN...WFO...BOI...LKN...PDT...REV...MFR...PQR...
   
   39391884 40252000 41862008 42232251 43122257 45402189
   45511851 44741731 42231521 40151489

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2581
   NWS STORM PREDICTION CENTER NORMAN OK
   0657 PM CST SUN DEC 18 2005
   
   AREAS AFFECTED...SW WA/MUCH OF ORE/SW ID/NRN UT
   
   CONCERNING...FREEZING RAIN/SNOW
   
   VALID 190057Z - 190600Z
   
   ...FZRA WILL AFFECT THE INTERIOR VALLEYS OF NW ORE/SW WA TONIGHT
   WITH MODERATE/HEAVY SNOW FROM THE COLUMBIA GORGE SEWD TO SW ID/NRN
   UT...
   
   FIRST IN A SERIES OF UPPER IMPULSES IS NOW ROTATING ONSHORE WITH AN
   UPPER CIRCULATION CENTER APPARENT IN EVENING WATER VAPOR IMAGERY
   MOVING INTO SW ORE. STAGNANT COLD AIRMASS HAS BEEN TRAPPED WITHIN
   THE VALLEYS FOR THE PAST FEW DAYS...AND WITH STRONG LARGE SCALE
   ASCENT AND MOISTURE IN PLACE...FZRA WILL RESULT ACROSS SOME
   LOCATIONS TONIGHT. THERE HAS BEEN FZRA DURING THE LAST COUPLE OF
   HOURS AT SALEM AND IN EUGENE EARLIER. 00Z SOUNDING FROM SALEM SHOWED
   NEAR FREEZING TEMPS FROM ABOUT 925MB-750MB...BUT RECENT MODERATE
   SNOW REPORTS IN/NEAR PORTLAND INDICATE THE COLUMN IS COLD ENOUGH FOR
   SNOW AT LEAST INITIALLY. VEERING PROFILE FROM BOTH ORE UPPER AIR
   SOUNDINGS IMPLIES CONTINUED WARMING...WITH A MIX OF PCPN TYPES
   POSSIBLE.
   
   FORECAST SOUNDINGS FROM THE NAM/RUC SUGGEST FZRA COULD SPREAD FROM
   PORTLAND NWD INTO THE INTERIOR VALLEYS OF SW WA BY 03Z AND NEAR
   OLYMPIA TOWARD 06Z. THE PTYPE ALGORITHM AND THE NCEP SREF SHOW AN
   EVEN STRONGER SIGNAL OF FZRA...ESPECIALLY AFTER 06Z. ACROSS NERN
   PORTIONS OF ORE INTO ID/UT...SNOW IS EXPECTED WITH HRLY RATES OF 1
   TO 2 INCHES PER HOUR POSSIBLE...AND BOUTS OF HEAVY SNOW WILL ALSO
   CONTINUE OVERNIGHT ACROSS THE WASATCH.
   
   ..TAYLOR.. 12/19/2005
   
   
   ATTN...WFO...SLC...PIH...BOI...LKN...OTX...PDT...SEW...PQR...
   
   41311512 44102090 44762407 46692299 47432121 45381690
   41701120 40691196

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2582
   NWS STORM PREDICTION CENTER NORMAN OK
   0957 AM CST MON DEC 19 2005
   
   AREAS AFFECTED...ERN/NRN ORE...SERN WA...AND WRN ID
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION
   
   VALID 191557Z - 192000Z
   
   FREEZING RAIN WILL DIMINISH IN INTENSITY OVER THE WRN COLUMBIA RIVER
   GORGE THROUGH 18Z...WHILE A MIX OF SLEET AND FREEZING RAIN WILL
   DEVELOP FURTHER EAST OVER THE COLUMBIA RIVER BASIN OF NERN ORE/SERN
   WA THROUGH 20Z. HRLY ACCUMULATIONS UP TO 0.10 FOR AN HOUR OR TWO
   WILL BE POSSIBLE. FURTHER SOUTH...LIGHT SNOW WILL CONTINUE TO
   DEVELOP OVER THE TREASURE VALLEY OF FAR SERN ORE/SWRN ID THROUGH
   18Z...BEFORE A MIX AND THEN CHANGE OVER TO SLEET/FREEZING RAIN
   OCCURS IN THIS AREA BETWEEN 18-20Z. ACCUMULATIONS RATES UP TO 0.10
   INCH/HR WILL BE POSSIBLE IN THIS AREA AS WELL.
   
   STRONG MID LEVEL ISENTROPIC LIFT WAS CONTRIBUTING TO AN ORGANIZED
   NW-SE ORIENTED BAND OF PRECIPITATION MOVING EWD ACROSS SRN WA AND
   ERN ORE. AS THE UPPER WAVE CONTRIBUTING TO THIS LIFTS INTO BRITISH
   COLUMBIA...EXPECT A STEADY EWD PROGRESS OF THIS PRECIPITATION ACROSS
   MUCH OF NERN ORE/SERN WA THROUGH THE EARLY AFTERNOON HOURS. RECENT
   RUC/NAM FORECAST SOUNDINGS INDICATE THAT LIGHT SNOW WILL CHANGE OVER
   TO FREEZING RAIN OVER MUCH OF THE COLUMBIA RIVER BASIN OF NERN
   ORE/SERN WA THROUGH 20Z. FURTHER EAST...ISENTROPIC ASCENT WAS JUST
   NOW MOVING INTO THE UPPER TREASURE VALLEY OF SERN ORE/SWRN ID. IN
   THIS AREA...STRONG WAA...EVIDENT BY 60 KT SWLY JET AT 700 MB PER
   MEDFORD VWP...SUGGESTS THAT LIGHT SNOW NOW DEVELOPING INTO THIS AREA
   WILL CHANGE OVER TO FREEZING RAIN/SLEET BETWEEN 18-20Z.
   
   ..CROSBIE.. 12/19/2005
   
   
   ATTN...WFO...MSO...BOI...OTX...PDT...SEW...PQR...
   
   46861735 47211930 47202100 46882142 46252177 45802181
   45312147 45042090 44931996 44511932 43631865 42781781
   42461733 42461578 43101540 44491601 46021678

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2583
   NWS STORM PREDICTION CENTER NORMAN OK
   0156 PM CST MON DEC 19 2005
   
   AREAS AFFECTED...NRN/ERN ORE...SWRN ID AND SRN WA-
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION
   
   VALID 191956Z - 200100Z
   
   MODERATE SNOW OVER THE TREASURE VALLEY MAY CHANGEOVER TO LIGHT
   FREEZING RAIN THROUGH 21Z...BEFORE WEAKENING TOWARDS 00Z. FURTHER
   NORTH MIXED PRECIP OVER NERN ORE/SERN WA...INCLUDING MUCH OF THE
   COLUMBIA RIVER BASIN...WILL CONTINUE TO DIMINISH THROUGH THE
   AFTERNOON. HOWEVER...A NEW AREA OF FREEZING RAIN WILL REDEVELOP
   AFTER 22Z IN THE DESCHUTES RIVER VALLEY OF NRN ORE AND OVER THE WRN
   COLUMBIA RIVER BASIN/GORGE AFTER 00Z.
   
   LATEST RADAR IMAGERY INDICATES A LARGE AREA OF PRECIPITATION OVER
   ERN ORE...ASSOCIATED WITH MODERATE-STRONG MID LEVEL WAA/ISENTROPIC
   LIFT. AS OF YET...THE WAA HAS BEEN INSUFFICIENT TO ALLOW FOR A
   CHANGEOVER TO FREEZING RAIN IN THE TREASURE VALLEY WITH MODERATE
   SNOWFALL THE PRIMARY P-TYPE. GIVEN RECENT TRENDS IN OBSERVATIONS AT
   BURNS /ELEV 4000 FT/ INDICATING ABOVE FREEZING TEMPERATURES
   DEVELOPING ...THERE IS STILL SOME POTENTIAL THAT SNOW WILL
   CHANGEOVER TO FREEZING RAIN BEFORE PRECIPITATION DIMINISHES BY LATE
   THIS AFTERNOON.
   
   FURTHER NW...RADAR IMAGERY AND SURFACE OBSERVATIONS INDICATE THAT
   WEAKENING MIXED PRECIP RATES WILL CONTINUE OVER MUCH OF THE COLUMBIA
   RIVER BASIN REGION THROUGH THE REMAINDER OF THE AFTERNOON AS MID
   LEVEL ISENTROPIC LIFT SHIFTS EWD AWAY FROM THE AREA. UPSTREAM OF
   THIS AREA...ANOTHER SURGE OF STRONG MID LEVEL WAA WAS BEGINNING
   AHEAD OF DEEP SYSTEM WELL OFF THE ORE COAST. THE ASSOCIATED
   PRECIPITATION WAS ALREADY ADVANCING NWD ALONG THE CENTRAL ORE COAST
   AND WILLAMETTE VALLEY. AS THIS PRECIPITATION ADVANCES
   NEWD...SUBFREEZING AIR WILL REMAIN IN PLACE OVER THE WRN COLUMBIA
   RIVER BASIN...COLUMBIA GORGE AND DESCHUTES VALLEY. THUS ANOTHER
   ROUND OF LIGHT TO MODERATE FREEZING RAIN WILL DEVELOP BETWEEN
   22-01Z.
   
   ..CROSBIE.. 12/19/2005
   
   
   ATTN...WFO...MSO...BOI...OTX...PDT...SEW...PQR...
   
   46911830 46751993 46592117 46392195 46222219 45492219
   45042202 44252169 44302124 44962022 45081900 44701828
   42881643 42671594 43311556 44691617 46701708

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2584
   NWS STORM PREDICTION CENTER NORMAN OK
   0730 PM CST MON DEC 19 2005
   
   AREAS AFFECTED...NERN ORE/ERN WA
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION
   
   VALID 200130Z - 200630Z
   
   FREEZING RAIN WILL CONTINUE TO DEVELOP OVER THE WRN COLUMBIA RIVER
   BASIN/GORGE OF NRN ORE THROUGH 03Z. FREEZING RAIN WILL EVENTUALLY
   DEVELOP INTO THE ERN SLOPES OF THE CASCADES AND COLUMBIA RIVER BASIN
   OF ERN WA BETWEEN 03-06Z. A COUPLE HOUR PERIOD OF HRLY PRECIP RATES
   UP TO 0.05 INCH WILL BE POSSIBLE...ESPECIALLY WITHIN 1-2 HOURS OF
   ONSET OF PRECIPITATION.
   
   AN AREA OF MOD-OCCASIONALLY HEAVY PRECIPITATION OVER NWRN ORE HAS
   DEVELOPED IN AN AREA OF MODERATE WAA AHEAD OF DEEP UPPER CYCLONE
   WELL OFF THE ORE COAST. THIS PRECIPITATION WILL CONTINUE TO SPREAD
   NEWD INTO THE COLUMBIA RIVER BASIN THROUGH THE LATE EVENING HOURS ON
   THE HEAL OF A 50-60 KT LOW LEVEL SSWLY JET. RECENT SURFACE
   OBSERVATIONS INDICATE HRLY RAINFALL RATES UP TO 0.2O INCH OVER THE
   NRN WILLAMETTE VALLEY. ALTHOUGH LOW LEVEL FLOW WILL REMAIN SSWLY
   WHICH SHOULD AID IN SOME SUBSIDENCE ON THE LEE-SIDE OF THE
   CASCADES...AND THUS LOWER HRLY PRECIP AMOUNTS...SUFFICIENTLY DEEP
   VERTICAL MOTION SHOULD ALLOW FOR LIGHT TO OCCASIONALLY MODERATE
   FREEZING RAIN TO DEVELOP INTO THE SERN SLOPES OF THE WA CASCADES AND
   COLUMBIA RIVER BASIN OF WA BETWEEN 03-06Z.
   
   FURTHER SOUTH...AS THE BULK OF THE LOW LEVEL LIFT/PRECIP CONTINUES
   TO MOVE NWD...EXPECT A DIMINISHING OF THE FREEZING RAIN RATES OVER
   THE DESCHUTES VALLEY THROUGH 06Z.
   
   ..CROSBIE.. 12/20/2005
   
   
   ATTN...WFO...OTX...PDT...PQR...
   
   47211981 47692030 47472102 47142094 46002160 45532231
   45032185 44682168 44632070 44672056 45421981 46461970

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2585
   NWS STORM PREDICTION CENTER NORMAN OK
   1123 AM CST SAT DEC 24 2005
   
   AREAS AFFECTED...PORTIONS SERN LA...SERN MS
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 241723Z - 242000Z
   
   GRADUAL INCREASE IN SEVERE POTENTIAL EXPECTED ACROSS LOWER MS DELTA
   REGION OF SERN LA AND COASTAL PLAIN OF SERN MS...THROUGH EARLY-MID
   AFTERNOON.  WW NOT ANTICIPATED SOON BUT MAY BE REQUIRED LATER THIS
   LATE AFTERNOON.
   
   INITIALLY...THROUGH ABOUT 19Z...REGIME WILL BE DIVIDED INTO
   1. INLAND MODE CHARACTERIZED BY ELEVATED BUOYANCY...ATOP STABLE BUT
   SLOWLY WARMING/MOISTENING SFC AIR MASS.
   2. NEAR-SHORE MODE WITH NRN EDGE OF MOST BUOYANT SFC AIR REMAINING
   OVER GULF...BUT NEARLY SFC-BASED LIFTED PARCELS POSSIBLE AS
   WAA...DIABATIC HEATING AND MOIST ADVECTION CONTINUE.  MUCH OF THIS
   AIR MASS HAS LIMITED MOISTURE RETURN BECAUSE OF EARLIER DRYING LEFT
   IN WAKE OF SRN STREAM PERTURBATION NOW CROSSING NERN GULF.
   
   INLAND TRANSITION ZONE BETWEEN THESE TWO REGIMES WILL BECOME
   NEBULOUS AS SLOPE OF BAROCLINIC SURFACE DECREASES...WHILE MUCAPES
   RISE INTO 500-800 J/KG RANGE BASED ON MODIFIED RUC SOUNDINGS.
   ALTHOUGH THIS SEEMS MARGINAL...EXPECT VERTICAL SHEAR PROFILES TO
   STRENGTHEN PAST FAVORABLE LEVELS OVER ENTIRE REGION AS MIDLEVEL
   CYCLONE DIGS SEWD ACROSS OZARKS REGION TOWARD LOWER MS
   VALLEY...TIGHTENING FLOW GRADIENTS OVER AREA.  STRONGEST CELLS
   EMBEDDED WITHIN BAND NOW MOVING ACROSS REGION MAY PRODUCE MARGINALLY
   SEVERE HAIL AND STRONG GUSTS.
   
   WLY SFC FLOW COMPONENT NOW OVER N-CENTRAL GULF SHOULD BACK AMIDST
   INCREASING ISALLOBARIC FORCING...AHEAD OF COLD FRONT ANALYZED FROM
   AR SWWD ACROSS SWRN LA.  ALTHOUGH LAPSE RATES WILL REMAIN WEAKLY
   CONVECTIVELY UNSTABLE...INCREASE IN MOISTURE AND SHEAR IN RECOVERY
   ZONE SHOULD RESULT IN SLOW BUILDUP OF SEVERE POTENTIAL...BOTH WITHIN
   ONGOING BAND AND IN ANY NEW CONVECTION THAT MAY DEVELOP FARTHER
   W...CLOSER TO COLD FRONT.
   
   ..EDWARDS.. 12/24/2005
   
   
   ATTN...WFO...MOB...JAN...LIX...LCH...
   
   29569225 30129159 30859059 31238986 31298899 30978849
   30518832 30378830 29328882 28958926 28938949 28959089
   29349157

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2586
   NWS STORM PREDICTION CENTER NORMAN OK
   0345 PM CST SAT DEC 24 2005
   
   AREAS AFFECTED...AL COASTAL PLAIN...PORTIONS WRN/CENTRAL FL
   PANHANDLE
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 242145Z - 242315Z
   
   OCCASIONAL STRONG-SEVERE TSTMS ARE POSSIBLE WITHIN PRIMARY
   CONVECTIVE BAND NOW OVER SWRN AL AND EXTREME SERN MS...AS IT MOVES
   INTO WRN FL PANHANDLE. MAIN THREAT OVER MOST INLAND AREAS WILL
   REMAIN MARGINALLY SEVERE HAIL. SLGT/CONDITIONAL POTENTIAL REMAINS
   FOR SFC-BASED SEVERE -- INCLUDING POSSIBILITY OF A TORNADO OR TWO --
   OVER COASTAL SECTIONS FL PANHANDLE THIS EVENING.  AREA CONTINUES TO
   BE MONITORED FOR POSSIBLE WW.
   
   COMPLEX SFC MESOANALYSIS FEATURES WAVY MARINE/WARM FRONTAL ZONE FROM
   ABOUT 75 SW HUM SEWD TO S OF MS RIVER MOUTH THEN NEWD NEARLY TO WRN
   FL PANHANDLE COAST...SEWD AGAIN TO ABOUT 50 SW AAF.  THERE...FRONT
   INTERSECTS OUTFLOW BOUNDARY FROM MORNING MCS OVER ERN GULF.  WRN
   BUOYANCY AXIS IS EVIDENT JUST AHEAD OF CONVECTIVE BAND AND SW OF MS
   RIVER MOUTH...SWWD ACROSS GULF.  THIS AIR MASS SHOULD NOT REACH GULF
   COAST BEFORE FROPA AND PRIOR PASSAGE OF CONVECTION.  FARTHER E --
   LOW LEVEL DRY POCKET REMAINS EVIDENT ACROSS N-CENTRAL GULF S OF
   MS/AL COASTS...IN WAKE OF PREVIOUS PERTURBATION...AND CHARACTERIZED
   BY SFC DEW POINTS IN MID/UPPER 50S F.  ANOTHER MOISTURE/BUOYANCY
   AXIS IS EVIDENT FROM APPROXIMATELY 100 SE BVE TO INTERSECTION WITH
   MARINE FRONT ABOUT 30 WSW PFN. INLAND...DIFFUSE SYNOPTIC WARM FRONT
   IS TAKING SHAPE FROM NEAR GZH ESEWD ACROSS TLH AREA.
   
   SEVERAL TSTMS HAVE FLARED TO MARGINAL SEVERE LEVELS WHILE CROSSING
   INLAND/SYNOPTIC FRONTAL ZONE.  THIS PROCESS SHOULD CONTINUE WITH
   ELEVATED MUCAPES 300-800 J/KG...BASED JUST ABOVE SFC...AND EFFECTIVE
   SHEARS VARYING FROM 35-50 KT IN MOST AREAS.  HOWEVER...RELATIVELY
   DRY INFLOW W OF ERN MOIST AXIS WILL LIMIT COVERAGE OF SEVERE THREAT
   UNTIL MAIN CONVERGENCE BAND REACHES WRN FL PANHANDLE AND ENCOUNTERS
   HIGHER THETAE IN INFLOW-LAYER. MEANWHILE...TSTMS HAVE FORMED ALONG
   OUTFLOW BOUNDARY S-SW AAF...SOME OF WHICH MAY APCH COAST NEAR AAF IN
   ANOTHER 2-3 HOURS.  ACTIVITY IN EITHER CONVECTIVE REGIME THAT HAS
   ACCESS TO LOW-MID 60S SFC DEW POINTS...WITHIN ERN MOISTURE
   PLUME...WILL BE SFC-BASED.  ASSOCIATED SEVERE RISK WILL BE MAXIMIZED
   INVOF MARINE FRONT...WHERE LOW LEVEL HODOGRAPHS AND VORTICITY EACH
   ARE MAXIMIZED.
   
   ..EDWARDS.. 12/24/2005
   
   
   ATTN...WFO...TAE...BMX...MOB...LIX...
   
   30278841 30818813 32318725 31728586 31378531 31128509
   30908494 29978423 29458491 28718623 29688617 29738796
   29748864