Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/19/13


AREA FORECAST DISCUSSION
NWS NEW YORK NY
241 PM EDT MON JUN 17 2013 .SYNOPSIS... A COLD FRONT MOVES INTO THE REGION TODAY...THEN STALLS OUT NEARBY INTO TUESDAY. THE COLD FRONT PUSHES SOUTHEAST OF THE REGION TUESDAY NIGHT...WITH A WEAK WAVE OF LOW PRESSURE PASSING SOUTH OF THE REGION ON WEDNESDAY. HIGH PRESSURE RETURNS FOR THE REST OF THE WEEK. A WARM FRONT APPROACHES THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SEVERE THUNDERSTORM WATCH 321 IN EFFECT UNTIL 9PM FOR SOUTHERN CONNECTICUT AND THE LOWER HUDSON VALLEY. ISOLATED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED THE LOWER HUDSON VALLEY AND SOUTHWESTERN CONNECTICUT. ISOLATED/SCATTERED SHOWERS/STORMS SHOULD CONTINUE TO DEVELOP THIS AFTERNOON...SPECIFICALLY ACROSS THE INTERIOR. THE PRIMARY THREAT FROM THESE STORMS WILL BE DAMAGING WINDS AND LARGE HAIL. PREVIOUS DISCUSSION FOLLOWS... WEAK 700-500 HPA SHORTWAVE CURRENTLY OVER THE OHIO VALLEY MOVES ACROSS THE AREA THIS AFTERNOON/EVENING. THIS COUPLED WITH A WEAK FRONT SAGGING INTO THE AREA SHOULD SERVE AS THE TRIGGER FOR A FEW SHOWERS/TSTORMS...ESPECIALLY ACROSS THE INTERIOR. 1500-2000 J/KG OF MUCAPE IS DEPICTED BY CURRENT SPC MESOANALYSIS WITH SUFFICIENT BULK SHEAR OF 40-50 KT. LATEST HRRR RUNS SHOW SCATTERED CONVECTION DEVELOPING ACROSS THE INTERIOR THIS AFTERNOON AND EVENING. WITH AFTERNOON SEA BREEZES AND LOWER INSTABILITY CLOSER TO THE COAST...ANTICIPATE ANY CONVECTION WEAKENING AS IT HEADS SOUTH THIS EVENING. THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... ANY CONVECTION SHOULD DIE OUT EARLY THIS EVENING WITH EXIT OF 700-500 HPA SHORTWAVE AND LOSS OF SOLAR HEATING. FOR LOWS TONIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES...WITH READINGS FORECAST TO BE A FEW DEGREES ABOVE NORMAL. 700-500 HPA NORTHERN STREAM TROUGH AXIS MOVES IN TUESDAY...AND SHOULD ACT ON STALLED FRONTAL BOUNDARY TO PRODUCE AT LEAST SCT SHRA/TSRA ACROSS THE TRI-STATE. STILL SOME VARIATION ON THE MODELS IN TERMS OF COVERAGE/STRENGTH SO KEPT POPS AT CHANCE FOR NOW. MAIN QUESTION IS STRENGTH OF INSTABILITY. NAM HAS 1500-2500 J/KG OF CAPE...WITH THE GFS ONLY AROUND 500 J/KG AND THE ECMWF SOMEWHERE IN BETWEEN. THE REGION WILL ALSO BE IN THE RIGHT REAR QUADRANT OF A 75+ KT 300 HPA JET...HAVE 40-50 KT OF BULK SHEAR...AND FAIRLY DECENT LOW LEVEL HELICITY. SO IF THE HIGHER INSTABILITY IN THE NAM CAN BE REALIZED...HAVE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS. IF NOT...THEN ONCE AGAIN SHOULD SEE MAINLY AIRMASS TSTMS...WITH MAYBE AN ISOLD LOW TOPPED SUPERCELL LIKE TODAY. FOR HIGHS TUESDAY USED A BLEND OF MIXING DOWN FROM 900 HPA NEAR THE COAST TO 825 HPA WELL INLAND...WITH NAM 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT HIGHS TO BE AROUND 5 DEGREES ABOVE NORMAL. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS COMING INTO SOMEWHAT BETTER AGREEMENT WITH EVOLUTION OF THE MAIN SYNOPTIC FEATURES FOR MIDWEEK...WITH A STRONG UPPER LOW CURLING THROUGH EASTERN CANADA AND A COLD FRONT PUSHING SOUTHEAST OF THE REGION TUESDAY NIGHT. THIS SHOULD HAVE ANY SHRA/TSRA ACTIVITY TUESDAY NIGHT WEAKENING AND GRADUALLY SINKING SE OF THE REGION. FOR WED...MODELS ARE KEYING IN ON SHORTWAVE ENERGY CURRENTLY OVER THE CANADIAN ROCKIES...ROUNDING THE BASE OF THE NE US TROUGH...AND HELPING TO INDUCE A WAVE OF LOW PRESSURE ALONG THE COLD FRONT. AT THIS POINT...IT APPEARS WE SHOULD BE MAINLY DRY...BUT COULD BE ON THE NORTHERN FRINGE OF ANY PRECIP WITH THIS FEATURE. IT WILL HAVE TO BE WATCHED. IF NOTHING ELSE...A BIT MORE CLOUD COVER AND ONSHORE FLOW TO THE NORTH OF THE LOW WOULD HOLD TEMPS BELOW SEASONABLE LEVELS. THEREAFTER...MODELS IN DECENT AGREEMENT WITH MEAN TROUGHING CONTINUING OVER THE NORTHEAST...WITH CANADIAN HIGH PRESSURE GRADUALLY BUILDING INTO THE REGION AND IN CONTROL THROUGH SATURDAY. THIS WILL RESULT IN FAIR AND SEASONABLE WARM CONDITIONS THROUGH THE PERIOD. WEAK PIECES OF SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH COULD SET OFF ISOLATED PULSE SHRA/TSRA ACTIVITY EACH AFT/EVE...MAINLY OFF THE NW HIGHER ELEVATIONS. HEIGHTS MAY BEGIN TO BUILD THIS WEEKEND INTO EARLY NEXT WEEK...WITH A TREND TOWARDS MORE SUMMER LIKE WEATHER. THIS WOULD ALSO BRING POTENTIAL FOR MCS ACTIVITY AS THE REGION LIES ON THE SOUTHERN EDGE OF THE WESTERLIES. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... THERE IS THE POTENTIAL FOR TWO EPISODES OF CONVECTION TO IMPACT THE TERMINALS...THE FIRST ALONG AND AHEAD OF A PRE-FRONTAL TROF THIS AFTERNOON...AND THEN AGAIN EARLY THIS EVENING AS A WEAK COLD FRONT DROPS SE ACROSS UPSTATE NY AND NEW ENGLAND. DUE TO STRONG WIND SHEAR ALOFT AND HIGH INSTABILITY...SOME OF THESE STORMS COULD BECOME STRONG...AND POSSIBLY SEVERE. THE MAIN SEVERE THREAT IS TO THE NORTH OF THE NYC TERMINALS AT THIS TIME. THE BEST CHANCE OF ORGANIZED CONVECTION WILL BE WITH THE COLD FRONT THIS EVENING. S/SW WINDS AT 8 TO 12 KT...G20KT FOR THE REST OF THIS AFTERNOON... BECOMING LIGHT AND VARIABLE THIS EVENING AS A COLD FRONT STALLS CLOSE TO THE AREA...THEN E/SE WED MORNING DEPENDING ON THE PROXIMITY OF THE FRONT. THERE IS UNCERTAINTY WITH THE GUIDANCE AS TO THE LOCATION OF THE FRONT TUE MORNING...WHICH WILL DEPEND OF THE AMOUNT OF SOUTHWARD PROGRESS IT MAKES THIS EVENING. WINDS ON TUE MAY VARY CONSIDERABLY FROM EITHER A LIGHT E/SE TO W/SW FLOW. GENERALLY VFR...BUT MVFR/IFR IN ANY CONVECTION. RESIDUAL LOW-LEVEL MOISTURE AND AN ONSHORE FLOW TONIGHT INTO TUE MAY ALSO RESULT IN FOG/HAZE...ESPECIALLY OUTSIDE OF THE NYC TERMINALS. POTENTIAL FOR ANOTHER ROUND OF STRONG CONVECTION TUE AFT...BUT THIS WILL HEAVILY DEPEND ON THE LOCATION OF THE FRONT. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS LIKELY DUE TO THE TIMING AND LOCATION OF CONVECTION THIS AFT AND EVE. KLGA FCSTER COMMENTS: AMENDMENTS LIKELY DUE TO THE TIMING AND LOCATION OF CONVECTION THIS AFT AND EVE. KEWR FCSTER COMMENTS: AMENDMENTS LIKELY DUE TO THE TIMING AND LOCATION OF CONVECTION THIS AFT AND EVE. KTEB FCSTER COMMENTS: AMENDMENTS LIKELY DUE TO THE TIMING AND LOCATION OF CONVECTION THIS AFT AND EVE. KHPN FCSTER COMMENTS: AMENDMENTS LIKELY DUE TO THE TIMING AND LOCATION OF CONVECTION THIS AFT AND EVE. KISP FCSTER COMMENTS: AMENDMENTS LIKELY DUE TO THE TIMING AND LOCATION OF CONVECTION THIS AFT AND EVE. .OUTLOOK FOR 18Z TUE THROUGH SAT... .TUE...SCT SHOWERS AND TSTMS COULD BRING MVFR OR LOWER CONDITIONS. .WED-SAT...VFR. && .MARINE... WAVEWATCH RUNNING AROUND 1 FT TOO HIGH...SO ADJUSTED DOWN A FT OR SO. WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE REGION EXPECT WINDS TO BE 10 KT OR LESS THROUGH TUESDAY...OUTSIDE OF AFTERNOON SEABREEZES EACH DAY AND ANY THUNDERSTORMS. WAVES...EVEN WITH A PERSISTENT 2 FT SWELL SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN WATERS THROUGH TUESDAY. MARGINAL SCA SEAS ARE POSSIBLE WEDNESDAY WITH A WEAK WAVE OF LOW PRESSURE MOVING TO THE SOUTH OF THE REGION. OTHERWISE...SUB SCA CONDITIONS ARE LIKELY FOR MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS IN. && .HYDROLOGY... BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING SHOULD BE LESS THAN .1 INCHES. WITH PRECIPITABLE WATERS AROUND 1 INCH...THE PROBABILITY OF LOCALLY HEAVY RAINFALL...AND HENCE ANY SIGNIFICANT HYDROLOGIC IMPACT IS LOW. THERE IS THE POTENTIAL FOR 1/3-2/3 AN INCH OF BASIN AVERAGE QPF...WITH LOCALLY HIGHER AMOUNTS POSSIBLE WITH CONVECTION TUESDAY/TUESDAY EVENING. WITH PRECIPITABLE WATERS OF 1.25-1.5 INCHES...THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH ANY STRONGER CONVECTION. THIS COULD CAUSE MINOR FLOODING OF URBAN/POOR DRAINAGE AREAS. THE PROBABILITY FOR WIDESPREAD SIGNIFICANT RAINFALL IS LOW FROM THE MIDDLE THROUGH THE END OF THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...MALOIT/NV NEAR TERM...DS SHORT TERM...MALOIT LONG TERM...NV AVIATION...DW MARINE...MALOIT/NV HYDROLOGY...MALOIT/NV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
140 PM EDT MON JUN 17 2013 .SYNOPSIS... A COLD FRONT MOVES INTO THE REGION TODAY...THEN STALLS OUT NEARBY INTO TUESDAY. THE COLD FRONT PUSHES SOUTHEAST OF THE REGION TUESDAY NIGHT...WITH A WEAK WAVE OF LOW PRESSURE PASSING SOUTH OF THE REGION ON WEDNESDAY. HIGH PRESSURE RETURNS FOR THE REST OF THE WEEK. A WARM FRONT APPROACHES THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SEVERE THUNDERSTORM WATCH 321 IN EFFECT UNTIL 9PM FOR SOUTHERN CONNECTICUT AND THE LOWER HUDSON VALLEY. ISOLATED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED THE LOWER HUDSON VALLEY AND SOUTHWESTERN CONNECTICUT. ISOLATED/SCATTERED SHOWERS/STORMS SHOULD CONTINUE TO DEVELOP THIS AFTERNOON...SPECIFICALLY ACROSS THE INTERIOR. THE PRIMARY THREAT FROM THESE STORMS WILL BE DAMAGING WINDS AND LARGE HAIL. PREVIOUS DISCUSSION FOLLOWS... WEAK 700-500 HPA SHORTWAVE CURRENTLY OVER THE OHIO VALLEY MOVES ACROSS THE AREA THIS AFTERNOON/EVENING. THIS COUPLED WITH A WEAK FRONT SAGGING INTO THE AREA SHOULD SERVE AS THE TRIGGER FOR A FEW SHOWERS/TSTORMS...ESPECIALLY ACROSS THE INTERIOR. 1500-2000 J/KG OF MUCAPE IS DEPICTED BY CURRENT SPC MESOANALYSIS WITH SUFFICIENT BULK SHEAR OF 40-50 KT. LATEST HRRR RUNS SHOW SCATTERED CONVECTION DEVELOPING ACROSS THE INTERIOR THIS AFTERNOON AND EVENING. WITH AFTERNOON SEA BREEZES AND LOWER INSTABILITY CLOSER TO THE COAST...ANTICIPATE ANY CONVECTION WEAKENING AS IT HEADS SOUTH THIS EVENING. THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... ANY CONVECTION SHOULD DIE OUT EARLY THIS EVENING WITH EXIT OF 700-500 HPA SHORTWAVE AND LOSS OF SOLAR HEATING. FOR LOWS TONIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES...WITH READINGS FORECAST TO BE A FEW DEGREES ABOVE NORMAL. 700-500 HPA NORTHERN STREAM TROUGH AXIS MOVES IN TUESDAY...AND SHOULD ACT ON STALLED FRONTAL BOUNDARY TO PRODUCE AT LEAST SCT SHRA/TSRA ACROSS THE TRI-STATE. STILL SOME VARIATION ON THE MODELS IN TERMS OF COVERAGE/STRENGTH SO KEPT POPS AT CHANCE FOR NOW. MAIN QUESTION IS STRENGTH OF INSTABILITY. NAM HAS 1500-2500 J/KG OF CAPE...WITH THE GFS ONLY AROUND 500 J/KG AND THE ECMWF SOMEWHERE IN BETWEEN. THE REGION WILL ALSO BE IN THE RIGHT REAR QUADRANT OF A 75+ KT 300 HPA JET...HAVE 40-50 KT OF BULK SHEAR...AND FAIRLY DECENT LOW LEVEL HELICITY. SO IF THE HIGHER INSTABILITY IN THE NAM CAN BE REALIZED...HAVE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS. IF NOT...THEN ONCE AGAIN SHOULD SEE MAINLY AIRMASS TSTMS...WITH MAYBE AN ISOLD LOW TOPPED SUPERCELL LIKE TODAY. FOR HIGHS TUESDAY USED A BLEND OF MIXING DOWN FROM 900 HPA NEAR THE COAST TO 825 HPA WELL INLAND...WITH NAM 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT HIGHS TO BE AROUND 5 DEGREES ABOVE NORMAL. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS COMING INTO SOMEWHAT BETTER AGREEMENT WITH EVOLUTION OF THE MAIN SYNOPTIC FEATURES FOR MIDWEEK...WITH A STRONG UPPER LOW CURLING THROUGH EASTERN CANADA AND A COLD FRONT PUSHING SOUTHEAST OF THE REGION TUESDAY NIGHT. THIS SHOULD HAVE ANY SHRA/TSRA ACTIVITY TUESDAY NIGHT WEAKENING AND GRADUALLY SINKING SE OF THE REGION. FOR WED...MODELS ARE KEYING IN ON SHORTWAVE ENERGY CURRENTLY OVER THE CANADIAN ROCKIES...ROUNDING THE BASE OF THE NE US TROUGH...AND HELPING TO INDUCE A WAVE OF LOW PRESSURE ALONG THE COLD FRONT. AT THIS POINT...IT APPEARS WE SHOULD BE MAINLY DRY...BUT COULD BE ON THE NORTHERN FRINGE OF ANY PRECIP WITH THIS FEATURE. IT WILL HAVE TO BE WATCHED. IF NOTHING ELSE...A BIT MORE CLOUD COVER AND ONSHORE FLOW TO THE NORTH OF THE LOW WOULD HOLD TEMPS BELOW SEASONABLE LEVELS. THEREAFTER...MODELS IN DECENT AGREEMENT WITH MEAN TROUGHING CONTINUING OVER THE NORTHEAST...WITH CANADIAN HIGH PRESSURE GRADUALLY BUILDING INTO THE REGION AND IN CONTROL THROUGH SATURDAY. THIS WILL RESULT IN FAIR AND SEASONABLE WARM CONDITIONS THROUGH THE PERIOD. WEAK PIECES OF SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH COULD SET OFF ISOLATED PULSE SHRA/TSRA ACTIVITY EACH AFT/EVE...MAINLY OFF THE NW HIGHER ELEVATIONS. HEIGHTS MAY BEGIN TO BUILD THIS WEEKEND INTO EARLY NEXT WEEK...WITH A TREND TOWARDS MORE SUMMER LIKE WEATHER. THIS WOULD ALSO BRING POTENTIAL FOR MCS ACTIVITY AS THE REGION LIES ON THE SOUTHERN EDGE OF THE WESTERLIES. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... A SURFACE TROUGH REMAINS OVER THE TERMINALS TODAY. WEAK COLD FRONT THEN DROPS DOWN FROM NW THIS EVE AND MAY PRODUCE SCT CONVECTION... PRIMARILY NORTH AND WEST OF THE NYC TERMINALS FROM 22Z TO 02Z. OTHERWISE...AN ISOLATED AFTERNOON SHOWER OR TSTM IS NOT OUT OF THE QUESTION. TIMING AND PLACEMENT TOO LOW TO INCLUDE IN THE TAFS FOR NOW. SOUTHWEST WINDS LESS THAN 10 KT TO START. SPEEDS GRADUALLY INCREASE THIS MORNING AND INTO THE AFTERNOON WITH SPEEDS BETWEEN 8-15 KT SUSTAINED. SEA BREEZES LIKELY AT THE COASTAL TERMINALS THIS AFTERNOON. OCCASIONAL GUSTS TO NEAR 20 KT ARE POSSIBLE TODAY. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS AND TO ADD POSSIBLE LATE DAY CONVECTION. AN OCCASIONAL GUST TO 20 KT CAN NOT BE RULED OUT. KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS AND TO ADD POSSIBLE LATE DAY CONVECTION. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADD POSSIBLE LATE DAY CONVECTION. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADD POSSIBLE LATE DAY CONVECTION. KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ACCOUNT FOR LATE DAY SEABREEZE AND TO ADD CONVECTION. KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. .OUTLOOK FOR 12Z TUE THROUGH FRI... .TUE...SCT SHOWERS AND ISOLD-SCT TSTMS COULD BRING MVFR OR LOWER CONDITIONS. .WED-FRI...VFR. && .MARINE... WAVEWATCH RUNNING AROUND 1 FT TOO HIGH...SO ADJUSTED DOWN A FT OR SO. WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE REGION EXPECT WINDS TO BE 10 KT OR LESS THROUGH TUESDAY...OUTSIDE OF AFTERNOON SEABREEZES EACH DAY AND ANY THUNDERSTORMS. WAVES...EVEN WITH A PERSISTENT 2 FT SWELL SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN WATERS THROUGH TUESDAY. MARGINAL SCA SEAS ARE POSSIBLE WEDNESDAY WITH A WEAK WAVE OF LOW PRESSURE MOVING TO THE SOUTH OF THE REGION. OTHERWISE...SUB SCA CONDITIONS ARE LIKELY FOR MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS IN. && .HYDROLOGY... BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING SHOULD BE LESS THAN .1 INCHES. WITH PRECIPITABLE WATERS AROUND 1 INCH...THE PROBABILITY OF LOCALLY HEAVY RAINFALL...AND HENCE ANY SIGNIFICANT HYDROLOGIC IMPACT IS LOW. THERE IS THE POTENTIAL FOR 1/3-2/3 AN INCH OF BASIN AVERAGE QPF...WITH LOCALLY HIGHER AMOUNTS POSSIBLE WITH CONVECTION TUESDAY/TUESDAY EVENING. WITH PRECIPITABLE WATERS OF 1.25-1.5 INCHES...THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH ANY STRONGER CONVECTION. THIS COULD CAUSE MINOR FLOODING OF URBAN/POOR DRAINAGE AREAS. THE PROBABILITY FOR WIDESPREAD SIGNIFICANT RAINFALL IS LOW FROM THE MIDDLE THROUGH THE END OF THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...MALOIT/NV NEAR TERM...DS SHORT TERM...MALOIT LONG TERM...NV AVIATION...DW MARINE...MALOIT/NV HYDROLOGY...MALOIT/NV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
104 PM EDT MON JUN 17 2013 .SYNOPSIS... A COLD FRONT MOVES INTO THE REGION TODAY...THEN STALLS OUT NEARBY INTO TUESDAY. THE COLD FRONT PUSHES SOUTHEAST OF THE REGION TUESDAY NIGHT...WITH A WEAK WAVE OF LOW PRESSURE PASSING SOUTH OF THE REGION ON WEDNESDAY. HIGH PRESSURE RETURNS FOR THE REST OF THE WEEK. A WARM FRONT APPROACHES THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ISOLATED SHOWERS AND THUNDERSTORMS HAS DEVELOPED OVER ORANGE COUNTY. OTHER ISOLATED SHOWERS/STORMS MAY CONTINUE TO DEVELOP THIS AFTERNOON...SPECIFICALLY ACROSS THE INTERIOR. UPDATED OTHER GRIDS TO REFLECT CURRENT TRENDS IN THE NEAR TERM. 1630 UTC SPC DAY ONE OUTLOOK HAS PLACED PORTIONS OF OUR AREA IN A SLIGHT RISK FOR SEVERE STORMS...MAINLY OVER SOUTHERN CONNECTICUT. THE PRIMARY THREAT WILL BE DAMAGING WINDS. OTHERWISE...WEAK 700-500 HPA SHORTWAVE CURRENTLY OVER THE OHIO VALLEY MOVES ACROSS THE AREA THIS AFTERNOON/EVENING. THIS COUPLED WITH A WEAK FRONT SAGGING INTO THE AREA SHOULD SERVE AS THE TRIGGER FOR A FEW SHOWERS/TSTORMS...ESPECIALLY ACROSS THE INTERIOR. 1500-2000 J/KG OF MUCAPE IS DEPICTED BY CURRENT SPC MESOANALYSIS WITH SUFFICIENT BULK SHEAR OF 40-50 KT. LATEST HRRR RUNS SHOW SCATTERED CONVECTION DEVELOPING ACROSS THE INTERIOR THIS AFTERNOON AND EVENING. WITH AFTERNOON SEA BREEZES AND LOWER INSTABILITY CLOSER TO THE COAST...ANTICIPATE ANY CONVECTION WEAKENING AS IT HEADS SOUTH THIS EVENING. THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... ANY CONVECTION SHOULD DIE OUT EARLY THIS EVENING WITH EXIT OF 700-500 HPA SHORTWAVE AND LOSS OF SOLAR HEATING. FOR LOWS TONIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES...WITH READINGS FORECAST TO BE A FEW DEGREES ABOVE NORMAL. 700-500 HPA NORTHERN STREAM TROUGH AXIS MOVES IN TUESDAY...AND SHOULD ACT ON STALLED FRONTAL BOUNDARY TO PRODUCE AT LEAST SCT SHRA/TSRA ACROSS THE TRI-STATE. STILL SOME VARIATION ON THE MODELS IN TERMS OF COVERAGE/STRENGTH SO KEPT POPS AT CHANCE FOR NOW. MAIN QUESTION IS STRENGTH OF INSTABILITY. NAM HAS 1500-2500 J/KG OF CAPE...WITH THE GFS ONLY AROUND 500 J/KG AND THE ECMWF SOMEWHERE IN BETWEEN. THE REGION WILL ALSO BE IN THE RIGHT REAR QUADRANT OF A 75+ KT 300 HPA JET...HAVE 40-50 KT OF BULK SHEAR...AND FAIRLY DECENT LOW LEVEL HELICITY. SO IF THE HIGHER INSTABILITY IN THE NAM CAN BE REALIZED...HAVE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS. IF NOT...THEN ONCE AGAIN SHOULD SEE MAINLY AIRMASS TSTMS...WITH MAYBE AN ISOLD LOW TOPPED SUPERCELL LIKE TODAY. FOR HIGHS TUESDAY USED A BLEND OF MIXING DOWN FROM 900 HPA NEAR THE COAST TO 825 HPA WELL INLAND...WITH NAM 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT HIGHS TO BE AROUND 5 DEGREES ABOVE NORMAL. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS COMING INTO SOMEWHAT BETTER AGREEMENT WITH EVOLUTION OF THE MAIN SYNOPTIC FEATURES FOR MIDWEEK...WITH A STRONG UPPER LOW CURLING THROUGH EASTERN CANADA AND A COLD FRONT PUSHING SOUTHEAST OF THE REGION TUESDAY NIGHT. THIS SHOULD HAVE ANY SHRA/TSRA ACTIVITY TUESDAY NIGHT WEAKENING AND GRADUALLY SINKING SE OF THE REGION. FOR WED...MODELS ARE KEYING IN ON SHORTWAVE ENERGY CURRENTLY OVER THE CANADIAN ROCKIES...ROUNDING THE BASE OF THE NE US TROUGH...AND HELPING TO INDUCE A WAVE OF LOW PRESSURE ALONG THE COLD FRONT. AT THIS POINT...IT APPEARS WE SHOULD BE MAINLY DRY...BUT COULD BE ON THE NORTHERN FRINGE OF ANY PRECIP WITH THIS FEATURE. IT WILL HAVE TO BE WATCHED. IF NOTHING ELSE...A BIT MORE CLOUD COVER AND ONSHORE FLOW TO THE NORTH OF THE LOW WOULD HOLD TEMPS BELOW SEASONABLE LEVELS. THEREAFTER...MODELS IN DECENT AGREEMENT WITH MEAN TROUGHING CONTINUING OVER THE NORTHEAST...WITH CANADIAN HIGH PRESSURE GRADUALLY BUILDING INTO THE REGION AND IN CONTROL THROUGH SATURDAY. THIS WILL RESULT IN FAIR AND SEASONABLE WARM CONDITIONS THROUGH THE PERIOD. WEAK PIECES OF SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH COULD SET OFF ISOLATED PULSE SHRA/TSRA ACTIVITY EACH AFT/EVE...MAINLY OFF THE NW HIGHER ELEVATIONS. HEIGHTS MAY BEGIN TO BUILD THIS WEEKEND INTO EARLY NEXT WEEK...WITH A TREND TOWARDS MORE SUMMER LIKE WEATHER. THIS WOULD ALSO BRING POTENTIAL FOR MCS ACTIVITY AS THE REGION LIES ON THE SOUTHERN EDGE OF THE WESTERLIES. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... A SURFACE TROUGH REMAINS OVER THE TERMINALS TODAY. WEAK COLD FRONT THEN DROPS DOWN FROM NW THIS EVE AND MAY PRODUCE SCT CONVECTION... PRIMARILY NORTH AND WEST OF THE NYC TERMINALS FROM 22Z TO 02Z. OTHERWISE...AN ISOLATED AFTERNOON SHOWER OR TSTM IS NOT OUT OF THE QUESTION. TIMING AND PLACEMENT TOO LOW TO INCLUDE IN THE TAFS FOR NOW. SOUTHWEST WINDS LESS THAN 10 KT TO START. SPEEDS GRADUALLY INCREASE THIS MORNING AND INTO THE AFTERNOON WITH SPEEDS BETWEEN 8-15 KT SUSTAINED. SEA BREEZES LIKELY AT THE COASTAL TERMINALS THIS AFTERNOON. OCCASIONAL GUSTS TO NEAR 20 KT ARE POSSIBLE TODAY. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS AND TO ADD POSSIBLE LATE DAY CONVECTION. AN OCCASIONAL GUST TO 20 KT CAN NOT BE RULED OUT. KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS AND TO ADD POSSIBLE LATE DAY CONVECTION. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADD POSSIBLE LATE DAY CONVECTION. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADD POSSIBLE LATE DAY CONVECTION. KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ACCOUNT FOR LATE DAY SEABREEZE AND TO ADD CONVECTION. KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. .OUTLOOK FOR 12Z TUE THROUGH FRI... .TUE...SCT SHOWERS AND ISOLD-SCT TSTMS COULD BRING MVFR OR LOWER CONDITIONS. .WED-FRI...VFR. && .MARINE... WAVEWATCH RUNNING AROUND 1 FT TOO HIGH...SO ADJUSTED DOWN A FT OR SO. WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE REGION EXPECT WINDS TO BE 10 KT OR LESS THROUGH TUESDAY...OUTSIDE OF AFTERNOON SEABREEZES EACH DAY AND ANY THUNDERSTORMS. WAVES...EVEN WITH A PERSISTENT 2 FT SWELL SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN WATERS THROUGH TUESDAY. MARGINAL SCA SEAS ARE POSSIBLE WEDNESDAY WITH A WEAK WAVE OF LOW PRESSURE MOVING TO THE SOUTH OF THE REGION. OTHERWISE...SUB SCA CONDITIONS ARE LIKELY FOR MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS IN. && .HYDROLOGY... BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING SHOULD BE LESS THAN .1 INCHES. WITH PRECIPITABLE WATERS AROUND 1 INCH...THE PROBABILITY OF LOCALLY HEAVY RAINFALL...AND HENCE ANY SIGNIFICANT HYDROLOGIC IMPACT IS LOW. THERE IS THE POTENTIAL FOR 1/3-2/3 AN INCH OF BASIN AVERAGE QPF...WITH LOCALLY HIGHER AMOUNTS POSSIBLE WITH CONVECTION TUESDAY/TUESDAY EVENING. WITH PRECIPITABLE WATERS OF 1.25-1.5 INCHES...THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH ANY STRONGER CONVECTION. THIS COULD CAUSE MINOR FLOODING OF URBAN/POOR DRAINAGE AREAS. THE PROBABILITY FOR WIDESPREAD SIGNIFICANT RAINFALL IS LOW FROM THE MIDDLE THROUGH THE END OF THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...MALOIT/NV NEAR TERM...DS SHORT TERM...MALOIT LONG TERM...NV AVIATION...DW MARINE...MALOIT/NV HYDROLOGY...MALOIT/NV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1104 AM EDT MON JUN 17 2013 .SYNOPSIS... A COLD FRONT MOVES INTO THE REGION TODAY...THEN STALLS OUT NEARBY INTO TUESDAY. A COLD FRONT PUSHES SOUTHEAST OF THE REGION TUESDAY NIGHT...WITH A WEAK WAVE OF LOW PRESSURE PASSING SOUTH OF THE REGION ON WEDNESDAY. HIGH PRESSURE RETURNS FOR THE REST OF THE WEEK. A WARM FRONT APPROACHES THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED GRIDS TO REFLECT CURRENT TRENDS. LOWERED SKY COVER THROUGH THE EARLY AFTERNOON AS MID-HIGH LEVEL CLOUDS HAVE SHIFTED OFFSHORE. FORECAST HIGH TEMPERATURES AROUND 5 DEGREES ABOVE NORMAL ACCEPTED. OTHERWISE...A WEAK 700-500 HPA SHORTWAVE CURRENTLY OVER THE OHIO VALLEY MOVES ACROSS THE AREA THIS AFTERNOON/EVENING. THIS COUPLED WITH A WEAK COLD FRONT SAGGING INTO THE AREA SHOULD SERVE AS THE TRIGGER FOR A FEW SHOWERS/TSTORMS...ESPECIALLY ACROSS THE INTERIOR. 1000-1500 J/KG OF CAPE IS FORECAST BY THE RAP/NAM/SREF. LATEST 12Z NAM AND HRRR RUNS SHOW SCATTERED CONVECTION DEVELOPING NORTH OF THE REGION AND MOVING INTO THE INTERIOR THIS EVENING. MODEL SOUNDINGS INDICATE DRY AIR THAT MAY SERVE TO INHIBIT CONVECTIVE DEVELOPMENT. HAVE CONTINUED TO FORECAST CHANCE POPS ACROSS THE INTERIOR WITH SLIGHT CHANCE POPS FURTHER SOUTH DUE TO AFTERNOON SEA BREEZES AND LOWER INSTABILITY. IN ADDITION TO THE AFOREMENTIONED CAPE...FORECAST TO HAVE 40-50 KT OF BULK SHEAR. A STRONG TO POSSIBLY SEVERE STORM CANNOT BE RULED OUT ACROSS THE INTERIOR WITH FORECAST BULK SHEAR VALUES 40-50 KT AND WET BULB ZERO HEIGHTS 7500-9500 FT COULD SEE SOME SMALL TO POSSIBLY LARGE HAIL ALONG WITH GUSTY WINDS. THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... ANY CONVECTION SHOULD DIE OUT EARLY THIS EVENING WITH EXIT OF 700-500 HPA SHORTWAVE AND LOSS OF SOLAR HEATING. FOR LOWS TONIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES...WITH READINGS FORECAST TO BE A FEW DEGREES ABOVE NORMAL. 700-500 HPA NORTHERN STREAM TROUGH AXIS MOVES IN TUESDAY...AND SHOULD ACT ON STALLED FRONTAL BOUNDARY TO PRODUCE AT LEAST SCT SHRA/TSRA ACROSS THE TRI-STATE. STILL SOME VARIATION ON THE MODELS IN TERMS OF COVERAGE/STRENGTH SO KEPT POPS AT CHANCE FOR NOW. MAIN QUESTION IS STRENGTH OF INSTABILITY. NAM HAS 1500-2500 J/KG OF CAPE...WITH THE GFS ONLY AROUND 500 J/KG AND THE ECMWF SOMEWHERE IN BETWEEN. THE REGION WILL ALSO BE IN THE RIGHT REAR QUADRANT OF A 75+ KT 300 HPA JET...HAVE 40-50 KT OF BULK SHEAR...AND FAIRLY DECENT LOW LEVEL HELICITY. SO IF THE HIGHER INSTABILITY IN THE NAM CAN BE REALIZED...HAVE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS. IF NOT...THEN ONCE AGAIN SHOULD SEE MAINLY AIRMASS TSTMS...WITH MAYBE AN ISOLD LOW TOPPED SUPERCELL LIKE TODAY. FOR HIGHS TUESDAY USED A BLEND OF MIXING DOWN FROM 900 HPA NEAR THE COAST TO 825 HPA WELL INLAND...WITH NAM 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT HIGHS TO BE AROUND 5 DEGREES ABOVE NORMAL. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS COMING INTO SOMEWHAT BETTER AGREEMENT WITH EVOLUTION OF THE MAIN SYNOPTIC FEATURES FOR MIDWEEK...WITH A STRONG UPPER LOW CURLING THROUGH EASTERN CANADA AND A COLD FRONT PUSHING SOUTHEAST OF THE REGION TUESDAY NIGHT. THIS SHOULD HAVE ANY SHRA/TSRA ACTIVITY TUESDAY NIGHT WEAKENING AND GRADUALLY SINKING SE OF THE REGION. FOR WED...MODELS ARE KEYING IN ON SHORTWAVE ENERGY CURRENTLY OVER THE CANADIAN ROCKIES...ROUNDING THE BASE OF THE NE US TROUGH...AND HELPING TO INDUCE A WAVE OF LOW PRESSURE ALONG THE COLD FRONT. AT THIS POINT...IT APPEARS WE SHOULD BE MAINLY DRY...BUT COULD BE ON THE NORTHERN FRINGE OF ANY PRECIP WITH THIS FEATURE. IT WILL HAVE TO BE WATCHED. IF NOTHING ELSE...A BIT MORE CLOUD COVER AND ONSHORE FLOW TO THE NORTH OF THE LOW WOULD HOLD TEMPS BELOW SEASONABLE LEVELS. THEREAFTER...MODELS IN DECENT AGREEMENT WITH MEAN TROUGHING CONTINUING OVER THE NORTHEAST...WITH CANADIAN HIGH PRESSURE GRADUALLY BUILDING INTO THE REGION AND IN CONTROL THROUGH SATURDAY. THIS WILL RESULT IN FAIR AND SEASONABLE WARM CONDITIONS THROUGH THE PERIOD. WEAK PIECES OF SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH COULD SET OFF ISOLATED PULSE SHRA/TSRA ACTIVITY EACH AFT/EVE...MAINLY OFF THE NW HIGHER ELEVATIONS. HEIGHTS MAY BEGIN TO BUILD THIS WEEKEND INTO EARLY NEXT WEEK...WITH A TREND TOWARDS MORE SUMMER LIKE WEATHER. THIS WOULD ALSO BRING POTENTIAL FOR MCS ACTIVITY AS THE REGION LIES ON THE SOUTHERN EDGE OF THE WESTERLIES. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... A SURFACE TROUGH REMAINS OVER THE TERMINALS TODAY. WEAK COLD FRONT THEN DROPS DOWN FROM NW THIS EVE AND MAY PRODUCE SCT CONVECTION... PRIMARILY NORTH AND WEST OF THE NYC TERMINALS FROM 22Z TO 02Z. OTHERWISE...AN ISOLATED AFTERNOON SHOWER OR TSTM IS NOT OUT OF THE QUESTION. TIMING AND PLACEMENT TOO LOW TO INCLUDE IN THE TAFS FOR NOW. SOUTHWEST WINDS LESS THAN 10 KT TO START. SPEEDS GRADUALLY INCREASE THIS MORNING AND INTO THE AFTERNOON WITH SPEEDS BETWEEN 8-15 KT SUSTAINED. SEA BREEZES LIKELY AT THE COASTAL TERMINALS THIS AFTERNOON. OCCASIONAL GUSTS TO NEAR 20 KT ARE POSSIBLE TODAY. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS AND TO ADD POSSIBLE LATE DAY CONVECTION. AN OCCASIONAL GUST TO 20 KT CAN NOT BE RULED OUT. KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS AND TO ADD POSSIBLE LATE DAY CONVECTION. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADD POSSIBLE LATE DAY CONVECTION. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADD POSSIBLE LATE DAY CONVECTION. KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ACCOUNT FOR LATE DAY SEABREEZE AND TO ADD CONVECTION. KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. .OUTLOOK FOR 12Z TUE THROUGH FRI... .TUE...SCT SHOWERS AND ISOLD-SCT TSTMS COULD BRING MVFR OR LOWER CONDITIONS. .WED-FRI...VFR. && .MARINE... WAVEWATCH RUNNING AROUND 1 FT TOO HIGH...SO ADJUSTED DOWN A FT OR SO. WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE REGION EXPECT WINDS TO BE 10 KT OR LESS THROUGH TUESDAY...OUTSIDE OF AFTERNOON SEABREEZES EACH DAY AND ANY THUNDERSTORMS. WAVES...EVEN WITH A PERSISTENT 2 FT SWELL SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN WATERS THROUGH TUESDAY. MARGINAL SCA SEAS ARE POSSIBLE WEDNESDAY WITH A WEAK WAVE OF LOW PRESSURE MOVING TO THE SOUTH OF THE REGION. OTHERWISE...SUB SCA CONDITIONS ARE LIKELY FOR MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS IN. && .HYDROLOGY... BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING SHOULD BE LESS THAN .1 INCHES. WITH PRECIPITABLE WATERS AROUND 1 INCH...THE PROBABILITY OF LOCALLY HEAVY RAINFALL...AND HENCE ANY SIGNIFICANT HYDROLOGIC IMPACT IS LOW. THERE IS THE POTENTIAL FOR 1/3-2/3 AN INCH OF BASIN AVERAGE QPF...WITH LOCALLY HIGHER AMOUNTS POSSIBLE WITH CONVECTION TUESDAY/TUESDAY EVENING. WITH PRECIPITABLE WATERS OF 1.25-1.5 INCHES...THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH ANY STRONGER CONVECTION. THIS COULD CAUSE MINOR FLOODING OF URBAN/POOR DRAINAGE AREAS. THE PROBABILITY FOR WIDESPREAD SIGNIFICANT RAINFALL IS LOW FROM THE MIDDLE THROUGH THE END OF THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1026 AM EDT MON JUN 17 2013 .SYNOPSIS... A COLD FRONT MOVES INTO THE REGION TODAY...THEN STALLS OUT NEARBY INTO TUESDAY. A COLD FRONT PUSHES SOUTHEAST OF THE REGION TUESDAY NIGHT...WITH A WEAK WAVE OF LOW PRESSURE PASSING SOUTH OF THE REGION ON WEDNESDAY. HIGH PRESSURE RETURNS FOR THE REST OF THE WEEK. A WARM FRONT APPROACHES THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED GRIDS TO REFLECT CURRENT TRENDS. LOWERED SKY COVER THROUGH THE EARLY AFTERNOON AS MID-HIGH LEVEL CLOUDS HAVE SHIFTED OFFSHORE. FORECAST HIGH TEMPERATURES AROUND 5 DEGREES ABOVE NORMAL ACCEPTED. OTHERWISE...A WEAK 700-500 HPA SHORTWAVE CURRENTLY OVER THE OHIO VALLEY MOVES ACROSS THE AREA THIS AFTERNOON/EVENING. THIS COUPLED WITH A WEAK COLD FRONT SAGGING INTO THE AREA SHOULD SERVE AS THE TRIGGER FOR A FEW SHOWERS/TSTORMS...ESPECIALLY ACROSS THE INTERIOR. 1000-1500 J/KG OF CAPE IS FORECAST BY THE RAP/NAM/SREF. LATEST 12Z NAM AND HRRR RUNS SHOW SCATTERED CONVECTION DEVELOPING NORTH OF THE REGION AND MOVING INTO THE INTERIOR THIS EVENING. MODEL SOUNDINGS INDICATE DRY AIR THAT MAY SERVE TO INHIBIT CONVECTIVE DEVELOPMENT. HAVE CONTINUED TO FORECAST CHANCE POPS ACROSS THE INTERIOR WITH SLIGHT CHANCE POPS FURTHER SOUTH DUE TO AFTERNOON SEA BREEZES AND LOWER INSTABILITY. IN ADDITION TO THE AFOREMENTIONED CAPE...FORECAST TO HAVE 40-50 KT OF BULK SHEAR. A STRONG TO POSSIBLY SEVERE STORM CANNOT BE RULED OUT ACROSS THE INTERIOR WITH FORECAST BULK SHEAR VALUES 40-50 KT AND WET BULB ZERO HEIGHTS 7500-9500 FT COULD SEE SOME SMALL TO POSSIBLY LARGE HAIL ALONG WITH GUSTY WINDS. THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... ANY CONVECTION SHOULD DIE OUT EARLY THIS EVENING WITH EXIT OF 700-500 HPA SHORTWAVE AND LOSS OF SOLAR HEATING. FOR LOWS TONIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES...WITH READINGS FORECAST TO BE A FEW DEGREES ABOVE NORMAL. 700-500 HPA NORTHERN STREAM TROUGH AXIS MOVES IN TUESDAY...AND SHOULD ACT ON STALLED FRONTAL BOUNDARY TO PRODUCE AT LEAST SCT SHRA/TSRA ACROSS THE TRI-STATE. STILL SOME VARIATION ON THE MODELS IN TERMS OF COVERAGE/STRENGTH SO KEPT POPS AT CHANCE FOR NOW. MAIN QUESTION IS STRENGTH OF INSTABILITY. NAM HAS 1500-2500 J/KG OF CAPE...WITH THE GFS ONLY AROUND 500 J/KG AND THE ECMWF SOMEWHERE IN BETWEEN. THE REGION WILL ALSO BE IN THE RIGHT REAR QUADRANT OF A 75+ KT 300 HPA JET...HAVE 40-50 KT OF BULK SHEAR...AND FAIRLY DECENT LOW LEVEL HELICITY. SO IF THE HIGHER INSTABILITY IN THE NAM CAN BE REALIZED...HAVE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE STORMS. IF NOT...THEN ONCE AGAIN SHOULD SEE MAINLY AIRMASS TSTMS...WITH MAYBE AN ISOLD LOW TOPPED SUPERCELL LIKE TODAY. FOR HIGHS TUESDAY USED A BLEND OF MIXING DOWN FROM 900 HPA NEAR THE COAST TO 825 HPA WELL INLAND...WITH NAM 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT HIGHS TO BE AROUND 5 DEGREES ABOVE NORMAL. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODELS COMING INTO SOMEWHAT BETTER AGREEMENT WITH EVOLUTION OF THE MAIN SYNOPTIC FEATURES FOR MIDWEEK...WITH A STRONG UPPER LOW CURLING THROUGH EASTERN CANADA AND A COLD FRONT PUSHING SOUTHEAST OF THE REGION TUESDAY NIGHT. THIS SHOULD HAVE ANY SHRA/TSRA ACTIVITY TUESDAY NIGHT WEAKENING AND GRADUALLY SINKING SE OF THE REGION. FOR WED...MODELS ARE KEYING IN ON SHORTWAVE ENERGY CURRENTLY OVER THE CANADIAN ROCKIES...ROUNDING THE BASE OF THE NE US TROUGH...AND HELPING TO INDUCE A WAVE OF LOW PRESSURE ALONG THE COLD FRONT. AT THIS POINT...IT APPEARS WE SHOULD BE MAINLY DRY...BUT COULD BE ON THE NORTHERN FRINGE OF ANY PRECIP WITH THIS FEATURE. IT WILL HAVE TO BE WATCHED. IF NOTHING ELSE...A BIT MORE CLOUD COVER AND ONSHORE FLOW TO THE NORTH OF THE LOW WOULD HOLD TEMPS BELOW SEASONABLE LEVELS. THEREAFTER...MODELS IN DECENT AGREEMENT WITH MEAN TROUGHING CONTINUING OVER THE NORTHEAST...WITH CANADIAN HIGH PRESSURE GRADUALLY BUILDING INTO THE REGION AND IN CONTROL THROUGH SATURDAY. THIS WILL RESULT IN FAIR AND SEASONABLE WARM CONDITIONS THROUGH THE PERIOD. WEAK PIECES OF SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH COULD SET OFF ISOLATED PULSE SHRA/TSRA ACTIVITY EACH AFT/EVE...MAINLY OFF THE NW HIGHER ELEVATIONS. HEIGHTS MAY BEGIN TO BUILD THIS WEEKEND INTO EARLY NEXT WEEK...WITH A TREND TOWARDS MORE SUMMER LIKE WEATHER. THIS WOULD ALSO BRING POTENTIAL FOR MCS ACTIVITY AS THE REGION LIES ON THE SOUTHERN EDGE OF THE WESTERLIES. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... A SURFACE TROUGH REMAINS OVER THE TERMINALS TODAY. SOUTHWEST WINDS LESS THAN 10 KT TO START. SPEEDS GRADUALLY INCREASE THIS MORNING AND INTO THE AFTERNOON WITH SPEEDS BETWEEN 8-15 KT SUSTAINED. SEA BREEZES LIKELY AT THE COASTAL TERMINALS THIS AFTERNOON. OCCASIONAL GUSTS TO NEAR 20 KT ARE POSSIBLE TODAY. AN AFTERNOON SHOWER OR TSTM POSSIBLE INLAND. TIMING AND PLACEMENT TOO LOW TO INCLUDE IN THE TAFS FOR NOW. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. AN OCCASIONAL GUST TO 20 KT CAN NOT BE RULED OUT. KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE RULED OUT. .OUTLOOK FOR 12TUE THROUGH FRI... .TUE...SCT SHOWERS AND ISOLD-SCT TSTMS COULD BRING MVFR OR LOWER CONDITIONS. .WED-FRI...VFR. && .MARINE... WAVEWATCH RUNNING AROUND 1 FT TOO HIGH...SO ADJUSTED DOWN A FT OR SO. WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE REGION EXPECT WINDS TO BE 10 KT OR LESS THROUGH TUESDAY...OUTSIDE OF AFTERNOON SEABREEZES EACH DAY AND ANY THUNDERSTORMS. WAVES...EVEN WITH A PERSISTENT 2 FT SWELL SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN WATERS THROUGH TUESDAY. MARGINAL SCA SEAS ARE POSSIBLE WEDNESDAY WITH A WEAK WAVE OF LOW PRESSURE MOVING TO THE SOUTH OF THE REGION. OTHERWISE...SUB SCA CONDITIONS ARE LIKELY FOR MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS IN. && .HYDROLOGY... BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING SHOULD BE LESS THAN .1 INCHES. WITH PRECIPITABLE WATERS AROUND 1 INCH...THE PROBABILITY OF LOCALLY HEAVY RAINFALL...AND HENCE ANY SIGNIFICANT HYDROLOGIC IMPACT IS LOW. THERE IS THE POTENTIAL FOR 1/3-2/3 AN INCH OF BASIN AVERAGE QPF...WITH LOCALLY HIGHER AMOUNTS POSSIBLE WITH CONVECTION TUESDAY/TUESDAY EVENING. WITH PRECIPITABLE WATERS OF 1.25-1.5 INCHES...THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH ANY STRONGER CONVECTION. THIS COULD CAUSE MINOR FLOODING OF URBAN/POOR DRAINAGE AREAS. THE PROBABILITY FOR WIDESPREAD SIGNIFICANT RAINFALL IS LOW FROM THE MIDDLE THROUGH THE END OF THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...MALOIT/NV NEAR TERM...DS SHORT TERM...MALOIT LONG TERM...NV AVIATION...BC MARINE...MALOIT/NV HYDROLOGY...MALOIT/NV
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
400 PM EDT MON JUN 17 2013 .SYNOPSIS... 19Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A NEARLY ZONAL FLOW ALONG THE NORTHERN GULF COAST THIS AFTERNOON OVER-TOP AN EAST-WEST ORIENTED UPPER LEVEL RIDGE ACROSS THE CENTRAL GULF OF MEXICO AND FLORIDA PENINSULA. AT THE SURFACE...SUBTROPICAL RIDGE AXIS IS ALIGNED ACROSS THE STATE JUST TO THE NORTH OF LAKE OKEECHOBEE. SYNOPTIC FLOW AROUND THIS RIDGE IS HELPING TO ACCELERATE THE SEA-BREEZE INLAND ACROSS THE NATURE COAST WITH A SLOWER INLAND EXPANSION FURTHER SOUTH WHERE THE FLOW IS LIGHTER OR EVEN SLIGHTLY OPPOSED. THUNDERSTORM ACTIVITY HAS BEEN RATHER LIMITED SO FAR WITH WIDELY SCT CELLS TRYING TO DEVELOP ALONG AND INLAND FROM THE I-75 CORRIDOR. && .SHORT TERM (TONIGHT THROUGH WEDNESDAY)... REST OF TODAY INTO TONIGHT... STILL ANTICIPATE AN ACTIVE EVENING OF THUNDERSTORMS ACROSS THE INTERIOR CENTRAL AND SOUTHERN ZONES TO THE SOUTH OF TAMPA BAY. HIGH RESOLUTION GUIDANCE WAS ACTUALLY HINTING AT A LATE START...AND PLENTY OF DAYLIGHT/HEATING LEFT TO GO. EAST AND WEST COAST SEA-BREEZE COLLISION WILL BE MAXIMIZED LATER THIS AFTERNOON FROM POLK COUNTY TO HIGHLANDS AND THEN SOUTHWEST TOWARD FT. MYERS. WILL KEEP CHANCE POPS IN THE GRIDS THROUGH THE LATE EVENING HOURS FOR THESE AREA. FURTHER NORTH...ESPECIALLY NORTH OF I-4...THE ONLY CHANCES FOR STORMS NOW LOOKS TO BE WELL INLAND WITH THE PROPAGATING SEA-BREEZE...AND EVENTUALLY THIS CONVERGENT ZONE SHOULD PUSH EAST OF OUR COUNTIES INTO NORTHEAST FLORIDA AND END THE THUNDERSTORM THREAT. TUESDAY THROUGH WEDNESDAY... UPPER LEVEL PATTERN WILL BEGIN TO SLOWLY AMPLIFY OVER THE EASTERN THIRD OF THE NATION INTO THE MIDDLE PART OF THE WEEK AND HELP PUSH A COLD FRONT INTO THE SOUTHEASTERN STATES. TYPICAL FOR THIS TIME OF YEAR...THIS FRONT WILL NOT REACH OUR AREA AND IS PROGGED BY GLOBAL GUIDANCE TO STALL AND WASH OUT NEAR THE I-10 CORRIDOR. THE SUBTROPICAL RIDGE AXIS WILL HOLD STRONG ACROSS THE FORECAST AREA AND KEEP OUR WEATHER PATTERN FAIRLY TYPICAL FOR MID/LATE JUNE. FOR TUESDAY...SOME INDICATIONS OF A LESS FAVORABLE THERMODYNAMIC COLUMN FOR DEEP CONVECTION ALONG WITH A QUICKLY MOVING SEA-BREEZE WILL KEEP POPS LOWER TO THE NORTH OF I-4. BY WEDNESDAY...THE RIDGE AXIS IS SUPPRESSED DOWN TOWARD OUR SOUTHERN ZONES BY THE FRONT TO OUR NORTH. THIS POSITION SHOULD SET UP A LARGER PORTION OF AREA TO SEE A QUICKLY MOVING SEA-BREEZE...AND LOWER RAIN CHANCES AT THE COAST. HAVE NOTICED A WARMING OF THE SHELF WATERS IN THE PAST WEEK OR 2 AND RESULTING SPIKE IN COASTAL DEWPOINTS LATELY. FOR THIS REASON...HEAT INDICES HAVE BECOME MORE OF AN ISSUE ONCE AGAIN. FORECAST THE NEXT FEW DAYS WILL SHOW MAXIMUM HEAT INDICES BETWEEN 100-105 DEGREES...ESPECIALLY NEAR THE COAST. && .LONG TERM (WEDNESDAY NIGHT-SUNDAY)... WEAK U/L TROUGH WILL REMAIN OVER THE SOUTHEAST U.S. AND NORTHEAST GULF THURSDAY AND FRIDAY...WITH THE WESTERLIES LIFTING WELL NORTH OF THE AREA OVER THE GREAT LAKES AND NORTHEAST ON FRIDAY AS AN U/L RIDGE OVER THE WESTERN ATLANTIC BUILDS WESTWARD. THIS WILL PINCH OFF THE WEAK TROUGH OVER THE SOUTHEAST U.S. AND NORTHEAST GULF SEPARATING IT FROM THE WESTERLIES...WHICH WILL THEN PERSIST JUST NORTH OF THE AREA THROUGH THE WEEKEND. A WEAK SURFACE FRONTAL BOUNDARY WILL REMAIN OVER NORTH FLORIDA THURSDAY...TRANSITIONING INTO A WEAK INVERTED TROUGH WHICH WILL EXTEND FROM THE NORTHEAST GULF OFF THE GEORGIA/S CAROLINA COAST. SURFACE RIDGE AXIS WILL GRADUALLY SHIFT EAST OF THE REGION LATE THURSDAY...WITH BOUNDARY LAYER WINDS SHIFTING FROM THE SOUTHWEST ON THURSDAY TO THE EAST-SOUTHEAST FRIDAY THROUGH SUNDAY. SCATTERED THUNDERSTORMS WILL DEVELOP EACH AFTERNOON...WITH MAJORITY OF ACTIVITY OVER THE INTERIOR THURSDAY DUE TO THE ONSHORE FLOW. FRIDAY WILL BE A TRANSITION DAY WITH ACTIVITY PRIMARILY OVER THE INTERIOR POSSIBLY PUSHING TOWARD THE COAST LATE IN THE DAY. EAST TO SOUTHEAST FLOW SATURDAY AND SUNDAY WILL HOLD THE WEST COAST SEA BREEZE OVER THE COASTAL COUNTIES WHICH WILL BE THE FOCUS FOR AFTERNOON THUNDERSTORMS...MOST NUMEROUS AS THE EAST COAST SEA BREEZE COLLIDES WITH THE WEST COAST SEA BREEZE DURING THE LATE AFTERNOON EACH DAY. DAYTIME TEMPERATURES WILL RUN NEAR CLIMATIC NORMALS THURSDAY...THEN A FEW DEGREES ABOVE NORMAL FRIDAY THROUGH THE WEEKEND AS WINDS SHIFT TO THE EAST-SOUTHEAST. && .AVIATION... AS WINDS SHIFT TO SW AND WEST ISOLD TSRA NOW FORMING WILL MOVE INLAND AS THEY BECOME SCT. STILL LOOKING FOR VCNTY TSRA/CB ONLY INLAND AND SOUTH DURING THIS AFTERNOON. SOUTHERN TERMINALS COULD SEE ISOLD SHRA IN A 01Z-06Z WINDOW. WINDS BECOME VARIABLE OR LIGHT SE OVERNIGHT. && .MARINE... THE SUBTROPICAL RIDGE AXIS WILL REMAIN IN PLACE OVER THE EASTERN GULF OF MEXICO FOR THE NEXT SEVERAL DAYS. WINDS WILL GENERALLY BE LIGHT WITH THE EXCEPTION OF SOME STEADIER ONSHORE FLOW DURING THE AFTERNOON AND EVENING WITH SEA BREEZE DEVELOPMENT. && .FIRE WEATHER... HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS THE FLORIDA PENINSULA THROUGH THE NEXT SEVERAL DAYS. A TYPICAL SUMMER PATTERN WITH ABUNDANT LOW LEVEL MOISTURE SHOULD HELP PREVENT ANY CRITICAL LEVELS OF RELATIVE HUMIDITY. MAXIMUM DAILY HEAT INDICES WILL BE ELEVATED WITH TYPICAL VALUES OF 98 TO 104 DEGREES COMMON. FOG POTENTIAL...PATCHY INLAND FOG IS EXPECTED THE NEXT COUPLE OF NIGHTS...ESPECIALLY FOR THOSE LOCATIONS THAT RECEIVE SIGNIFICANT LATE AFTERNOON OR EVENING RAINFALL FROM DAILY THUNDERSTORMS. && .PRELIMINARY POINT TEMPS/POPS... TPA 76 93 77 92 / 10 20 10 20 FMY 76 93 76 93 / 30 40 20 40 GIF 74 94 74 93 / 40 40 20 40 SRQ 75 90 76 90 / 10 20 10 20 BKV 70 93 72 93 / 10 20 10 20 SPG 79 91 79 91 / 10 20 10 20 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA AVIATION...RUDE LONG TERM...JELSEMA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
506 AM EDT Mon Jun 17 2013 ...UPDATED FOR AVIATION DISCUSSION... .NEAR TERM [Today]... The large scale longwave pattern is highlighted by an elongated ridge over the Nrn Gulf of Mex with high centered over W/Cntrl Gulf. North of this ridge axis, exists moist quasi-zonal flow across SE region and into the Wrn Atlc. However, a series of embedded short- waves will continue to ride Ewd in this flow. During the predawn hours, latest satellite imagery shows lead impulse over NW GA thru S/Cntrl AL and into Gulf of Mex. At surface, Atlc high well east of Carolinas with ridge axis WSW across Nrn Gulf region. Approaching impulse continues to shunt surface ridge SEWD resulting in a moistening up of deep layer moisture underneath the zonal flow including a veering of low level flow. All this reflected in area model soundings. i.e. GFS TAE with PWATS increasing from 1.38 to 1.92 inches from 12z Mon to 00z Tues, also 24 hr comparisons show dew points running 4 to 9 degrees higher than same time yesterday with models showing a return to inland aftn dewpoints around 70 degrees. With moist near surface conditions from recent rains, patchy light fog or stratus may persist past sunrise. RAP shows that shortwave will move ewd across FL/AL then FL/GA border area during the late morning into the aftn. At surface, deep WSW steering flow will drive Gulf seabreeze inland into late aftn and to I-10 and beyond during eve. So models to show that the juxtaposition of passing shortwave and lifting seabreeze plus any convection that develops along mesoscale boundaries will generate a good chance of storms today. HI RES guidance like WRF and NM4 imply that focus should be across SE AL and Nrn tier GA counties in the late aftn into eve when closest to seabreeze and when impulse providing best lift. Strong to isold severe storms possible but any severe threat should remain isolated and brief pulsy as is typical for summer. i.e. RAP 21z Mon for SE AL with good cape 3200 J/KG but 0-6km shear only 20kts, BRN shear only 20 m/s and 700-500mb lapse rate of 6c/km. Will go with sharp 60-10% NW-SE pop gradient. Expect inland highs in the low 90s. && .SHORT TERM [Tonight Through Tuesday Night]... A broad low amplitude upper level trough over the eastern CONUS will gradually deepen as a series of impulses eject out of the Plains. Deep layer moisture will be on increase and a cold front will drop down into northern AL/GA by 00z Wednesday. The deepest moisture and best upper level support will be over the northern portions of the forecast area. PoPs on Tuesday will be tapered from good chance/likely for our AL and most Georgia zones with chances PoPs for all Florida zones (30-40%) except the southeast Big Bend (20%). Expect slight to chance PoPs for the nighttime periods. Max and min temps will remain near seasonal averages. && .LONG TERM [Wednesday through Sunday]... A fairly seasonal period is expected with scattered afternoon and evening convection each day. Some days will likely have slightly higher PoPs than others depending on the timing of individual weak shortwaves, which is hard to forecast in the long term. No major synoptic scale system are expected to impact the area during the period. Temperatures are expected to remain near their seasonal averages. && .AVIATION [Through 12z Tuesday]... Expect MVFR ceilings/vsbys in fog to settle in briefly rest of predawn hoUrs. Brief IFR possible around sunrise especially at TLH and also at DHN and VLD. Conditions should improve to VFR after 14z. Showers and thunderstorms starting in the late morning/early afternoon and all sites will include VCTS with prob30 TSRA at DHN and ABY 20Z-24Z. Winds will be from the southeast around 5-10 kts becoming light southwest after sundown. After 08z, expect MVFR CIGS and possibly VSBYS to redevelop especially across VLD and TLH. IFR CIGS remain possible exepcially at VLD near sunrise. && .MARINE... The subtropical ridge will be the dominant feature across the northern Gulf of Mexico this week, yielding mainly light southwest to west flow and low seas. && .FIRE WEATHER... Red Flag conditions are not expected thru the work week as RH values remain above critical levels. The combination of deep mixing and somewhat stronger winds aloft will help dispersion values climb above 75 Tues afternoon.] && .HYDROLOGY... River gauges are expected to remain below flood stage for at least the next several days. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 91 72 92 72 92 / 30 20 40 20 40 Panama City 87 75 90 75 87 / 40 20 30 20 40 Dothan 91 72 91 73 91 / 50 40 60 30 40 Albany 92 73 91 72 92 / 50 40 60 30 50 Valdosta 91 71 92 72 92 / 40 30 40 30 40 Cross City 92 69 92 71 91 / 10 20 20 20 20 Apalachicola 86 75 88 76 86 / 20 10 20 10 40 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ SHORT TERM...Barry MARINE...Barry/DVD NEAR TERM/AVIATION/FIRE WEATHER...Block LONG TERM/HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
347 AM EDT Mon Jun 17 2013 .NEAR TERM [Today]... The large scale longwave pattern is highlighted by an upper ridge moving slowly ewd across Rockies, an elongated ridge over the Nrn Gulf of Mex with high centered over W/Cntrl Gulf, and north of this ridge axis, a moist quasi-zonal flow across SE region and into the Wrn Atlc. A series of embedded impulses will continue to ride Ewd in this flow. Lead vort moving into Cntrl AL during pre-dawn hours spawning active convection across Cntrl GA but should remain well north of our area. At surface, Atlc high well east of Carolinas with ridge axis WSW across Nrn Gulf region. With moist near surface conditions from recent rains, patchy light fog or stratus may persist past sunrise. RAP shows another shortwave moving from Cntrl MS to Cntrl AL later today with vort lobe brushing our area in late aftn. At surface, Gulf seabreeze again expected to push Nwd into late aftn and eve. So models continue to show a moistening up of deep layer moisture underneath the zonal flow. All this reflected in area model soundings. i.e. GFS TAE with PWATS increasing from 1.38 to 1.92 inches from 12z Mon to 00z Tues, also 24 hr comparisons show dew points running 4 to 9 degrees higher than same time yesterday with models showing a return to inland aftn dewpoints around 70 degrees. The juxtaposition of passing impulse and lifting seabreeze plus any convection that develops along mesoscale boundaries will generate a good chance of storms today. HI RES guidance like WRF and NM4 imply that focus should be across SE AL and adjacent SW GA counties in the late aftn into eve when closest to seabreeze and when impulse providing best lift. Strong to isold severe storms possible but any severe threat should remain isolated and brief pulsy as is typical for summer. i.e. RAP 21z Mon for SE AL with good cape 3200 J/KG but 0-6km shear only 20kts, BRN shear only 20 m/s and 700-500mb lapse rate of 6c/km. Will go with sharp 60-10% NW-SE pop gradient. Expect inland highs in the low 90s. && .SHORT TERM [Tonight Through Tuesday Night]... A broad low amplitude upper level trough over the eastern CONUS will gradually deepen as a series of impulses eject out of the Plains. Deep layer moisture will be on increase and a cold front will drop down into northern AL/GA by 00z Wednesday. The deepest moisture and best upper level support will be over the northern portions of the forecast area. PoPs on Tuesday will be tapered from good chance/likely for our AL and most Georgia zones with chances PoPs for all Florida zones (30-40%) except the southeast Big Bend (20%). Expect slight to chance PoPs for the nighttime periods. Max and min temps will remain near seasonal averages. && .LONG TERM [Wednesday through Sunday]... A fairly seasonal period is expected with scattered afternoon and evening convection each day. Some days will likely have slightly higher PoPs than others depending on the timing of individual weak shortwaves, which is hard to forecast in the long term. No major synoptic scale system are expected to impact the area during the period. Temperatures are expected to remain near their seasonal averages. && .AVIATION [Through 06z Tuesday]... Expect MVFR ceilings/vsbys in fog to settle in briefly around 09-11Z. Brief IFR possible around sunrise especially at TLH and also at DHN and VLD. Conditions should improve to VFR after 14z. Showers and thunderstorms starting in the late morning/early afternoon and all sites will include VCTS with prob30 TSRA at DHN and ABY 20Z-24Z. Winds will be from the southeast around 5-10 kts becoming light southwest after sundown. && .MARINE... The subtropical ridge will be the dominant feature across the northern Gulf of Mexico this week, yielding mainly light southwest to west flow and low seas. && .FIRE WEATHER... Red Flag conditions are not expected thru the work week as RH values remain above critical levels. The combination of deep mixing and somewhat stronger winds aloft will help dispersion values climb above 75 Tues afternoon.] && .HYDROLOGY... River gauges are expected to remain below flood stage for at least the next several days. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 91 72 92 72 92 / 30 20 40 20 40 Panama City 87 75 90 75 87 / 40 20 30 20 40 Dothan 91 72 91 73 91 / 50 40 60 30 40 Albany 92 73 91 72 92 / 50 40 60 30 50 Valdosta 91 71 92 72 92 / 40 30 40 30 40 Cross City 92 69 92 71 91 / 10 20 20 20 20 Apalachicola 86 75 88 76 86 / 20 10 20 10 40 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ SHORT TERM...Barry MARINE...Barry/DVD NEAR TERM/AVIATION/FIRE WEATHER...Block LONG TERM/HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
214 PM EDT MON JUN 17 2013 .SYNOPSIS... HIGH PRESSURE OFF THE SOUTHEAST COAST HAS SHIFTED FARTHER EASTWARD AHEAD OF A WEAK FRONTAL ZONE MOVING SOUTHWARD AND INTO THE FORECAST AREA. THE FRONT AND ASSOCIATED MOISTURE WILL DOMINATE THE FORECAST AREA/S WEATHER THROUGH MUCH OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... THIS AFTERNOON...A WEAK SHORT WAVE WILL MOVE EASTWARD THROUGH THE REGION THIS AFTERNOON. THIS MAY HELP TO TRIGGER SOME CONVECTIVE ACTIVITY BUT EXPECT MAINLY JUST SCATTERED. A WEAKLY SHEARED ENVIRONMENT WITH JUST MARGINAL LIS -2/-3...TOTALS 44/45 AND CAPES LESS THAN 1000 J/KG. SOME HEAVY RAIN POSSIBLE IN SHOWERS AND THUNDERSTORMS WITH PWAT AROUND 1.90 INCHES. SIX HOUR QPF VALUES AROUND 0.10 OF AN INCH OR LESS. SO NOT MUCH FLOODING POTENTIAL EXPECTED. AND LATEST SATELLITE PCPN ESTIMATE KEEPS FLOODING POTENTIAL TO THE NORTH AND WEST IN THE LATEST SPENES. TONIGHT...MAINLY DIURNAL ACTIVITY BUT NAM BRINGS ANOTHER WEAK IMPULSE TO THE REGION LATE TONIGHT AFTER MIDNIGHT. SO...PLAN ON KEEPING AT LEAST SOME LOW CHANCE...SAY AROUND 30 PERCENT AFTER MIDNIGHT. OTHERWISE...EXPECT LOW TEMPERATURES MAINLY IN THE LOWER 70S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... LINGERING MOISTURE ASSOCIATED WITH AN EAST-WEST ORIENTED FRONT WILL CONTINUE TO AFFECT THE REGION. THE MODELS KEEP BROAD UPPER-LEVEL TROUGH WITH A SERIES OF SHORTWAVES MOVING THROUGH THE FLOW OVER THE FORECAST AREA. THIS WILL CONTINUE THE CHANCE FOR SHOWER AND THUNDERSTORM DEVELOPMENT TUESDAY AND TUESDAY NIGHT AND INTO WEDNESDAY. KEPT TEMPERATURES BELOW GUIDANCE WITH THE EXPECTED RAIN AND CLOUDINESS. && .LONG TERM /THURSDAY THRU MONDAY/... SURFACE HIGH PRESSURE BEGINS TO BUILD DOWN INTO THE CAROLINAS ON THURSDAY AND THE CHANCE OF SHOWERS AND THUNDERSTORMS LESSENS INTO THE WEEKEND BUT THERE REMAINS ENOUGH MOISTURE FOR POSSIBLE AFTERNOON SHOWERS AND THUNDERSTORMS. EXPECT HIGH TEMPERATURES NEAR OR A LITTLE BELOW CLIMATOLOGY. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... ONE SHORT WAVE MOVED EAST THIS MORNING BUT RUC13 BRINGS ANOTHER WEAK SHORT OVER THE REGION LATE THIS AFTERNOON ON INTO THE EVENING HOURS. THIS MAY HELP TO GENERATE MORE SHOWERS AND THUNDERSTORMS BUT FOR TIME BEING WILL JUST MENTION THUNDERSTORMS IN THE VICINITY 22Z-02Z ALL TAF SITES. MAINLY VFR CONDITIONS THIS AFTERNOON AND EVENING EXCEPT IF CONVECTIVE ACTIVITY DEVELOPS...MAY SEE BRIEF IFR-MVFR CONDITIONS. OVERNIGHT...WITH PLENTY OF LOW LEVEL MOISTURE AND LOW LEVEL WINDS BELOW 1 KFT SOUTHWEST 12-15 KNOTS...STRATUS IS A POSSIBILITY. MVFR CIGS OCCURRED THIS MORNING AT AGS...DNL AND OGB AND MVFR CIGS NEAR 2 KFT ARE EXPECTED AGAIN TUESDAY MORNING AROUND 10Z-13Z TIME FRAME. AFTER 13Z...MAINLY VFR CONDITIONS JUST LIKE TODAY BUT ANOTHER WEAK IMPULSE MOVES THROUGH TUESDAY AFTERNOON JUST LIKE TODAY AND MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE. HOWEVER...WILL NOT INCLUDE IN TAF SITES DUE TO UNCERTAINTY AS TO TIMING AND LOCATION. EXTENDED AVIATION OUTLOOK...CHANCE OF MAINLY AFTERNOON/EVENING THUNDERSTORMS. CHANCE OF LATE NIGHT/EARLY MORNING FOG/STRATUS. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
158 PM EDT MON JUN 17 2013 .SYNOPSIS... HIGH PRESSURE OFF THE SOUTHEAST COAST HAS SHIFTED FARTHER EASTWARD AHEAD OF A WEAK FRONTAL ZONE MOVING SOUTHWARD AND INTO THE FORECAST AREA. THE FRONT AND ASSOCIATED MOISTURE WILL DOMINATE THE FORECAST AREA/S WEATHER THROUGH MUCH OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... THIS AFTERNOON...A WEAK SHORT WAVE WILL MOVE EASTWARD THROUGH THE REGION THIS AFTERNOON. THIS MAY HELP TO TRIGGER SOME CONVECTIVE ACTIVITY BUT EXPECT MAINLY JUST SCATTERED. A WEAKLY SHEARED ENVIRONMENT WITH JUST MARGINAL LIS -2/-3...TOTALS 44/45 AND CAPES LESS THAN 1000 J/KG. SOME HEAVY RAIN POSSIBLE IN SHOWERS AND THUNDERSTORMS WITH PWAT AROUND 1.90 INCHES. SIX HOUR QPF VALUES AROUND 0.10 OF AN INCH OR LESS. SO NOT MUCH FLOODING POTENTIAL EXPECTED. AND LATEST SATELLITE PCPN ESTIMATE KEEPS FLOODING POTENTIAL TO THE NORTH AND WEST IN THE LATEST SPENES. TONIGHT...MAINLY DIURNAL ACTIVITY BUT NAM BRINGS ANOTHER WEAK IMPULSE TO THE REGION LATE TONIGHT AFTER MIDNIGHT. SO...PLAN ON KEEPING AT LEAST SOME LOW CHANCE...SAY AROUND 30 PERCENT AFTER MIDNIGHT. OTHERWISE...EXPECT LOW TEMPERATURES MAINLY IN THE LOWER 70S. && .SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/... HIGH MOISTURE ASSOCIATED WITH THE DIFFUSE EAST-WEST ORIENTED FRONT WILL CONTINUE. THE MODELS KEEP BROAD UPPER-LEVEL TROUGHING WITH A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH THE FLOW OVER THE FORECAST AREA. EXPECT NUMEROUS SHOWERS AND THUNDERSTORMS. LEANED TOWARD THE HIGHER GUIDANCE POPS. THE COOLER HIGH TEMPERATURE GUIDANCE APPEARS BETTER BECAUSE OF EXPECTED CLOUDINESS. THE LOW TEMPERATURE GUIDANCE WAS CONSISTENT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... THE GFS AND ECMWF DISPLAY THE FRONT REMAINING NEAR THE FORECAST AREA THROUGH THE MEDIUM-RANGE PERIOD. THERE HAS BEEN INCONSISTENCY IN THE PLACEMENT OF DEEPER MOISTURE. THE GFS ENSEMBLE MEANS AND OPERATIONAL GFS MOS SUPPORT CHANCE POPS THROUGH THE PERIOD. EXPECT HIGH TEMPERATURES NEAR OR A LITTLE BELOW CLIMATOLOGY. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... ONE SHORT WAVE MOVED EAST THIS MORNING BUT RUC13 BRINGS ANOTHER WEAK SHORT OVER THE REGION LATE THIS AFTERNOON ON INTO THE EVENING HOURS. THIS MAY HELP TO GENERATE MORE SHOWERS AND THUNDERSTORMS BUT FOR TIME BEING WILL JUST MENTION THUNDERSTORMS IN THE VICINITY 22Z-02Z ALL TAF SITES. MAINLY VFR CONDITIONS THIS AFTERNOON AND EVENING EXCEPT IF CONVECTIVE ACTIVITY DEVELOPS...MAY SEE BRIEF IFR-MVFR CONDITIONS. OVERNIGHT...WITH PLENTY OF LOW LEVEL MOISTURE AND LOW LEVEL WINDS BELOW 1 KFT SOUTHWEST 12-15 KNOTS...STRATUS IS A POSSIBILITY. MVFR CIGS OCCURRED THIS MORNING AT AGS...DNL AND OGB AND MVFR CIGS NEAR 2 KFT ARE EXPECTED AGAIN TUESDAY MORNING AROUND 10Z-13Z TIME FRAME. AFTER 13Z...MAINLY VFR CONDITIONS JUST LIKE TODAY BUT ANOTHER WEAK IMPULSE MOVES THROUGH TUESDAY AFTERNOON JUST LIKE TODAY AND MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE. HOWEVER...WILL NOT INCLUDE IN TAF SITES DUE TO UNCERTAINTY AS TO TIMING AND LOCATION. EXTENDED AVIATION OUTLOOK...CHANCE OF MAINLY AFTERNOON/EVENING THUNDERSTORMS. CHANCE OF LATE NIGHT/EARLY MORNING FOG/STRATUS. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
617 AM EDT MON JUN 17 2013 .SYNOPSIS... HIGH PRESSURE OFF THE SOUTHEAST COAST HAS SHIFTED FARTHER EASTWARD AHEAD OF A WEAK FRONTAL ZONE MOVING SOUTHWARD AND INTO THE FORECAST AREA. THE FRONT AND ASSOCIATED MOISTURE WILL DOMINATE THE FORECAST AREA/S WEATHER THROUGH MUCH OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE MID-LEVEL SHORTWAVE TROUGH APPROACHING THE FORECAST AREA THIS MORNING HAS REMOVED THE CAPPING THAT HAS BEEN DOMINATE DURING THE PAST FEW DAYS. MOISTURE HAS INCREASED AHEAD OF THE DIFFUSE FRONT DROPPING SOUTHWARD AND TOWARD THE FORECAST AREA. BELIEVE THE SHOWERS MOVING INTO THE FORECAST AREA FROM THE WEST EARLY THIS MORNING ARE MAINLY ASSOCIATED WITH THE MID-LEVEL SHORTWAVE TROUGH. THE HIGH-RESOLUTION MODELS SHOW COVERAGE DIMINISHING AS THESE SHOWERS MOVE INTO THE FORECAST AREA THIS MORNING. THEREFORE... WE DID NOT FORECAST CATEGORICAL POPS THROUGHOUT THE AREA. FORECASTED POPS OF 50 TO NEAR 100 PERCENT WITH THE HIGHEST POPS FOR NOW IN THE SOUTHWEST PART BASED ON RADAR TRENDS AND HRRR MODEL. THE NAM AND GFS SHOW PRECIPITABLE WATER AROUND 2 INCHES THIS AFTERNOON. THE HIGH MOISTURE AND HEATING SHOULD HELP SUPPORT THUNDERSTORMS BUT COVERAGE MAY BE LIMITED BECAUSE LIFT ASSOCIATED THIS MORNING/S SHORTWAVE TROUGH SHOULD BE EAST OF THE FORECAST AREA. THE HIGH RESOLUTION MODELS INDICATE SCATTERED COVERAGE. CLOUDINESS SHOULD LIMIT INSTABILITY TODAY. THE NAM DISPLAYS SURFACE-BASED LI/S -4 TO -5 TODAY. THE THREAT OF SEVERE THUNDERSTORMS APPEARS LOW BECAUSE OF THE LIMITED INSTABILITY. AN AVERAGE OF THE NAM AND GFS PLUS THE SREF MEAN SUPPORT GENERAL RAIN AMOUNTS NEAR ONE-HALF OF AN INCH. HEAVY RAIN MAY OCCUR BECAUSE OF THE HIGH PRECIPITABLE WATER AND POSSIBLE TRAINING. LEANED TOWARD THE COOLER TEMPERATURE GUIDANCE TODAY BECAUSE OF CLOUDINESS. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... HIGH MOISTURE ASSOCIATED WITH THE DIFFUSE EAST-WEST ORIENTED FRONT WILL CONTINUE. THE MODELS KEEP BROAD UPPER-LEVEL TROUGHING WITH A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH THE FLOW OVER THE FORECAST AREA. EXPECT NUMEROUS SHOWERS AND THUNDERSTORMS. LEANED TOWARD THE HIGHER GUIDANCE POPS. THE COOLER HIGH TEMPERATURE GUIDANCE APPEARS BETTER BECAUSE OF EXPECTED CLOUDINESS. THE LOW TEMPERATURE GUIDANCE WAS CONSISTENT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... THE GFS AND ECMWF DISPLAY THE FRONT REMAINING NEAR THE FORECAST AREA THROUGH THE MEDIUM-RANGE PERIOD. THERE HAS BEEN INCONSISTENCY IN THE PLACEMENT OF DEEPER MOISTURE. THE GFS ENSEMBLE MEANS AND OPERATIONAL GFS MOS SUPPORT CHANCE POPS THROUGH THE PERIOD. EXPECT HIGH TEMPERATURES NEAR OR A LITTLE BELOW CLIMATOLOGY. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... A WEAK SHORTWAVE CONTINUES TO MAINTAIN AN AREA OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS CURRENTLY OVER NORTHERN GA MOVING EASTWARD. SOME OF THE SHOWERS MAY MOVE OVER AGS/DNL. WILL INCLUDE A TEMPO GROUP FOR BOTH AGS AND DNL FOR SHRA UNTIL 14Z. AFTER ANY MORNING RESTRICTIONS...VFR EXPECTED TODAY OUTSIDE OF ANY CONVECTION. A DEEPENING UPPER TROUGH AND INCREASING ATMOSPHERIC MOISTURE IS EXPECTED TO LEAD TO SCATTERED THUNDERSTORMS MONDAY AFTERNOON...MAINLY AFTER 18Z. HAVE MENTION SHRA AFTER 21Z AT ALL TAF SITES BUT TSRA MAY BE POSSIBLE AS WELL. WILL CONTINUE MENTION OF SHRA IN THE TAFS TOWARDS THE END OF THE TAF PERIOD AS A SLOW- MOVING COLD FRONT APPROACHES FROM THE OH RIVER VALLEY. EXTENDED AVIATION OUTLOOK...CHANCE OF MAINLY AFTERNOON/EVENING THUNDERSTORMS. CHANCE OF LATE NIGHT/EARLY MORNING FOG/STRATUS. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
612 AM EDT MON JUN 17 2013 .SYNOPSIS... HIGH PRESSURE OFF THE SOUTHEAST COAST HAS SHIFTED FARTHER EASTWARD AHEAD OF A WEAK FRONTAL ZONE MOVING SOUTHWARD AND INTO THE FORECAST AREA. THE FRONT AND ASSOCIATED MOISTURE WILL DOMINATE THE FORECAST AREA/S WEATHER THROUGH MUCH OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE MID-LEVEL SHORTWAVE TROUGH APPROACHING THE FORECAST AREA THIS MORNING HAS REMOVED THE CAPPING THAT HAS BEEN DOMINATE DURING THE PAST FEW DAYS. MOISTURE HAS INCREASED AHEAD OF THE DIFFUSE FRONT DROPPING SOUTHWARD AND TOWARD THE FORECAST AREA. BELIEVE THE SHOWERS MOVING INTO THE FORECAST AREA FROM THE WEST EARLY THIS MORNING ARE MAINLY ASSOCIATED WITH THE MID-LEVEL SHORTWAVE TROUGH. THE HIGH-RESOLUTION MODELS SHOW COVERAGE DIMINISHING AS THESE SHOWERS MOVE INTO THE FORECAST AREA THIS MORNING. THEREFORE... WE DID NOT FORECAST CATEGORICAL POPS THROUGHOUT THE AREA. FORECASTED POPS OF 50 TO NEAR 100 PERCENT WITH THE HIGHEST POPS FOR NOW IN THE SOUTHWEST PART BASED ON RADAR TRENDS AND HRRR MODEL. THE NAM AND GFS SHOW PRECIPITABLE WATER AROUND 2 INCHES THIS AFTERNOON. THE HIGH MOISTURE AND HEATING SHOULD HELP SUPPORT THUNDERSTORMS BUT COVERAGE MAY BE LIMITED BECAUSE LIFT ASSOCIATED THIS MORNING/S SHORTWAVE TROUGH SHOULD BE EAST OF THE FORECAST AREA. THE HIGH RESOLUTION MODELS INDICATE SCATTERED COVERAGE. CLOUDINESS SHOULD LIMIT INSTABILITY TODAY. THE NAM DISPLAYS SURFACE-BASED LI/S -4 TO -5 TODAY. THE THREAT OF SEVERE THUNDERSTORMS APPEARS LOW BECAUSE OF THE LIMITED INSTABILITY. AN AVERAGE OF THE NAM AND GFS PLUS THE SREF MEAN SUPPORT GENERAL RAIN AMOUNTS NEAR ONE-HALF OF AN INCH. HEAVY RAIN MAY OCCUR BECAUSE OF THE HIGH PRECIPITABLE WATER AND POSSIBLE TRAINING. LEANED TOWARD THE COOLER TEMPERATURE GUIDANCE TODAY BECAUSE OF CLOUDINESS. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... HIGH MOISTURE ASSOCIATED WITH THE DIFFUSE EAST-WEST ORIENTED FRONT WILL CONTINUE. THE MODELS KEEP BROAD UPPER-LEVEL TROUGHING WITH A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH THE FLOW OVER THE FORECAST AREA. EXPECT NUMEROUS SHOWERS AND THUNDERSTORMS. LEANED TOWARD THE HIGHER GUIDANCE POPS. THE COOLER HIGH TEMPERATURE GUIDANCE APPEARS BETTER BECAUSE OF EXPECTED CLOUDINESS. THE LOW TEMPERATURE GUIDANCE WAS CONSISTENT. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... THE GFS AND ECMWF DISPLAY THE FRONT REMAINING NEAR THE FORECAST AREA THROUGH THE MEDIUM-RANGE PERIOD. THERE HAS BEEN INCONSISTENCY IN THE PLACEMENT OF DEEPER MOISTURE. THE GFS ENSEMBLE MEANS AND OPERATIONAL GFS MOS SUPPORT CHANCE POPS THROUGH THE PERIOD. EXPECT HIGH TEMPERATURES NEAR OR A LITTLE BELOW CLIMATOLOGY. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... A WEAK SHORTWAVE CONTINUES TO MAINTAIN AN AREA OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS CURRENTLY OVER NORTHERN GA MOVING EASTWARD. SOME OF THE SHOWERS MAY MOVE OVER AGS/DNL. AFTER ANY MORNING RESTRICTIONS...VFR EXPECTED MONDAY OUTSIDE OF ANY CONVECTION. A DEEPENING UPPER TROUGH AND INCREASING ATMOSPHERIC MOISTURE IS EXPECTED TO LEAD TO SCATTERED THUNDERSTORMS MONDAY AFTERNOON...MAINLY AFTER 18Z. HAVE MENTION SHRA AFTER 21Z AT ALL TAF SITES BUT TSRA MAY BE POSSIBLE AS WELL. WILL CONTINUE MENTION OF SHRA IN THE TAFS TOWARDS THE END OF THE TAF PERIOD AS A SLOW- MOVING COLD FRONT APPROACHES FROM THE OH RIVER VALLEY. EXTENDED AVIATION OUTLOOK...CHANCE OF MAINLY AFTERNOON/EVENING THUNDERSTORMS. CHANCE OF LATE NIGHT/EARLY MORNING FOG/STRATUS. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1004 PM CDT TUE JUN 18 2013 .DISCUSSION... 849 PM CDT VERY LITTLE CHANGE MADE TO THE GOING FORECAST FOR THE REST OF TONIGHT. THE HIGH PRESSURE RIDGE CONTINUES TO BUILD DOWN THE LAKE RESULTING IN A PRESSURE GRADIENT ACROSS NE IL AND NW IN. THIS COUPLED WITH THE LONG NNE FETCH OF THE WINDS OVER THE LAKE HAS CONTINUED TO ALLOW FOR 20+ MPH GUSTS EARLY THIS EVE. THESE LOOK SLOW TO SUBSIDE PER OBSERVATIONAL TRENDS AND THE RAP BUFKIT SOUNDINGS. SO THESE WILL ADD A LITTLE NIP IN THE AIR...BY JUNE STANDARDS...ACROSS CHICAGO WITH TEMPS FALLING SLOWLY THROUGH THE MID-UPPER 50S. THE COOLEST TEMPS TONIGHT STILL LOOK TO BE ALONG THE STATE LINE WHERE CONDITIONS SHOULD DECOUPLE. UPPER 40S SHOULD BE REALIZED THERE. MTF //PREV DISCUSSION... 239 PM CDT STRATUS LAYER THAT WAS ANCHORED OVER FAR NORTHEAST IL/NORTHWEST IN THIS MORNING HAS ERODED WITH THE WARM AIR HEATING THE SFC. VISIBLE IMAGERY INDICATES A FEW AREAS OF CUMULUS CLOUDS THAT HAVE DEVELOPED THIS AFTERNOON ACROSS NORTHERN IL. IN ADDITION SOME BUILDING CUMULUS CLOUDS WERE NOTED ALONG A PONTIAC TO KANKAKEE LINE...IN AN AREA OF A STRONGER THERMAL DIFFERENTIAL. HOWEVER THE LIFT MECHANISM IN THIS AREA IS MINIMAL...AND SO A FEW ISOLATED SHOWERS/THUNDERSTORMS MAY DEVELOP BUT QUICKLY DISSIPATE. ALL PRECIPITATION OVER THE CWFA WILL BE DIURNALLY DRIVEN...THUS BY SUNSET OR IMMEDIATELY AFTER SUNSET PRECIP WILL COME TO AN END. FURTHER SOUTH STRONGER INSTABILITY WAS POSITIONED ACROSS CENTRAL IL STRETCHING WEST THROUGH NORTHERN MISSOURI. MID-LVL WAVE CONTINUES TO PIVOT EAST ACROSS FAR NORTHWEST IL THIS AFTERNOON...AND WILL MAINTAIN THE NORTHEAST FLOW ACROSS MUCH OF THE CWFA. AS A RESULT COOL TEMPS WILL PERSIST THIS EVENING...WITH MINIMAL CLOUD COVER FROM THE DIFFLUENT FLOW ALOFT. SKIES WILL BECOME MOSTLY CLEAR TONIGHT...WITH THE LLVL FLOW WEAKENING. THIS SHOULD PROVIDE DECENT RADIATIONAL COOLING WITH TEMPS OVERNIGHT EXPECTED TO BE IN THE MID 50S SOUTH OF I-80. FURTHER NORTH TEMPS WILL BE MUCH COOLER TO ARND 50...POSSIBLY THE UPR 40S FOR AREAS ALONG AND NORTH OF A ROCKFORD...AURORA...WAUKEGAN LINE. CONFIDENCE...HIGH. WEDNESDAY THROUGH THURSDAY... 500MB TROUGH AXIS SLOWLY PIVOTS TO THE EASTERN GREAT LAKES WED...AND WILL CONTINUE TO PUSH EAST THUR. THE SFC RIDGE WILL ALSO BEGIN TO PUSH EAST...HOWEVER AN ONSHORE OR NORTHEAST TO EAST FLOW WILL PERSIST INTO WED FOR MUCH OF NORTHERN IL. THE DIFFERENCE FOR WED WILL BE THAT THE 850MB THERMAL TROUGH WILL LINGER OVERHEAD. WITH ABUNDANT SUNSHINE AND SFC HEATING...TEMPS SHUD WARM INTO THE MID/UPR 70S OR POSSIBLY THE LOW 80S FROM LASALLE TO IROQUOIS COUNTY. FOR THUR 500MB HEIGHTS WILL BEGIN TO RISE WITH FLOW BEGINNING TO TURN TO THE SOUTHEAST IN THE LLVLS. A WEAK LAKE BREEZE MAY DEVELOP AND PUSH INTO LAKE COUNTY IL...WHICH WOULD MOST LIKELY PROVIDE A COOLING TREND IN THE AFTN HOURS. 850MB TEMPS WILL STEADILY WARM FOR THUR TO ARND 14 TO 16 DEG C...WITH CONTINUED THIN CLOUD COVER. THIS WILL ALLOW TEMPS TO WARM INTO THE LOW/MID 80S. THE CAVEAT WILL BE AREAS OF LAKE COUNTY IL POST FRONTAL PASSAGE THAT WILL ALLOW TEMPS TO FALL INTO THE 60S IN THE AFTN. IT DOES APPEAR THAT ENOUGH DRY AIR WILL LINGER THRU THUR AFTN/EVE...THUS HAVE HELD ONTO A DRY FORECAST IN THIS TIMEFRAME. THIS PATTERN WILL BE CHANGING AS WE MIGRATE INTO THE EXTENDED PERIODS. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN DRY WEATHER THROUGH THUR...MEDIUM/HIGH. FRIDAY THROUGH MONDAY... MINIMAL CHANGES FROM PREVIOUS FORECAST IN REGARDS TO THE EXTENDED PERIODS. POSSIBLY THE FIRST STRETCH OF 90 DEG DAYS IS UPON US FOR SUN/MON/TUE. GUIDANCE HAS A WARM FRONTAL BOUNDARY LIFTING OVERHEAD FRI WITH SOUTHERLY FLOW USHERING IN ADDTL LLVL MOISTURE. IT DOES APPEAR A WAVE WILL ALSO PUSH OVER THE CWFA FRI...WITH POTENTIAL FOR SHOWERS/THUNDERSTORMS. TEMPS WILL BE SLIGHTLY WARM FOR FRI INTO THE UPR 80S...WITH A FEW 90 DEGREE POINTS ACROSS THE CWFA. ENSEMBLES FOR SEVERAL DAYS HAVE CONTINUED TO INDICATE THAT A 500MB RIDGE ACROSS THE CENTRAL CONUS WILL ADVECT EAST AND BECOME ANCHORED ACROSS THE EASTERN HALF OF THE CONUS BY THE WEEKEND AND POSSIBLY PERSIST THROUGH EARLY NEXT WEEK. ADDITIONALLY...GUIDANCE HAS PROGGED 850MB TEMPS TO RISE TO ARND 20-22 DEG C FOR THE WEEKEND THRU EARLY NEXT WEEK. CONSISTENCY FROM PREVIOUS RUNS SUGGESTS HIGH CONFIDENCE IN THIS WARM STRETCH ARRIVING. THEN SUN/MON/TUE APPEAR TO BE NEAR CARBON COPIES WITH TEMPS EASILY WARMING TO 90 DEGREES...POSSIBLY THE LOW 90S. CLIMATOLOGY BASED ON THE 850MB TEMPS PROGGED AND TIME OF YEAR WOULD SUGGEST TEMPS TO BE WARMER AS FORECASTED. A COUPLE LIMITING FACTORS MIGHT BE THE POTENTIAL FOR A SERIES OF WAVES BRINGING INSTABILITY AND THUNDERSTORM POTENTIAL EACH DAY OF THE EXTENDED...ALONG WITH DEW PTS PROGGED TO BE ARND 70 DEG. THIS COULD POTENTIALLY KEEP TEMPS IN CHECK IN THE MID/UPR 80S. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN PRECIP/CONVECTIVE FORECAST...MEDIUM/HIGH. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 03Z... * A FEW GUSTS INTO THE MID TEENS STILL POSSIBLE OVERNIGHT. * WIND TRENDS TOMORROW...LIKELY VARYING BETWEEN NORTHEAST AND EAST. LENNING //DISCUSSION...UPDATED 00Z... HIGH PRESSURE SITTING OVER LAKE MICHIGAN THIS EVENING WILL VERY GRADUALLY SLIDE EAST OVER THE NEXT TWO DAYS...SLOWLY VEERING WINDS FROM NORTHEAST TO SOUTHEAST AND EVENTUALLY BY THURSDAY AROUND TO THE SOUTH. THIS PATTERN SHOULD KEEP PRECIPITATION OUT OF THE AREA FOR A WHILE AND MAINTAIN GENERALLY CLEAR AND QUIET CONDITIONS. LENNING //ORD AND MDW CONFIDENCE...UPDATED 03Z... * MEDIUM CONFIDENCE IN WIND TRENDS. HIGH CONFIDENCE IN OTHER ELEMENTS. LENNING //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... THURSDAY...VFR. FRIDAY THROUGH MONDAY...PERIODIC CHANCES FOR TSRA...OTHERWISE VFR. LENNING && .MARINE... 137 PM CDT A SURFACE RIDGE OF HIGH PRESSURE ACROSS THE UPPER GREAT LAKES REGION...WILL SHIFT EASTWARD TOWARDS NEW ENGLAND BY WEDNESDAY EVENING. MEANWHILE...LOW PRESSURE IS EXPECTED TO TAKE SHAPE ACROSS THE PLAINS STATES. THIS PRESSURE PATTERN WILL REMAIN IN PLACE FOR A FEW DAYS INTO THE WEEKEND. OVERALL...THIS WILL RESULT IN A PROLONGED PERIOD OF SOUTHERLY WINDS ACROSS THE LAKE. WIND MAGNITUDES GENERALLY LOOK TO BE IN THE 10 TO 20 KT RANGE...WITH A FEW PERIODS OF 15 TO 25 KT SOUTHERLY WINDS...ESPECIALLY LATER IN THE PERIOD. THERE WILL ALSO BE INCREASING CHANCES FOR A FEW PERIODS OF THUNDERSTORM ACTIVITY FRIDAY AND INTO THE WEEKEND OVER THE LAKE. A FAIRLY ACTIVE WEATHER PATTERN LOOKS TO SETUP UP ACROSS THE GREAT THE NORTHERN CONUS AND GREAT LAKES REGION. IN THE SHORTER TERM...I HAVE EXTENDED THE SMALL CRAFT ADVISORY INTO THIS EVENING FOR THE ILLINOIS SHORES AND MAINTAINED THE ADVISORY THROUGH LATE TONIGHT FOR THE INDIANA SHORES. LOCAL BUOY OBS INDICATE WAVES AROUND 4 FT...AND WITH THE ONSHORE FLOW CONTINUING TO BE IN THE 15 TO 20 KT RANGE AHEAD OF THE SURFACE HIGH...I DO NOT SEE ANY IMPROVEMENT IN THE WAVE CONDITIONS FOR SEVERAL MORE HOURS. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 4 AM WEDNESDAY. IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 4 AM WEDNESDAY. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
849 PM CDT TUE JUN 18 2013 .DISCUSSION... 849 PM CDT VERY LITTLE CHANGE MADE TO THE GOING FORECAST FOR THE REST OF TONIGHT. THE HIGH PRESSURE RIDGE CONTINUES TO BUILD DOWN THE LAKE RESULTING IN A PRESSURE GRADIENT ACROSS NE IL AND NW IN. THIS COUPLED WITH THE LONG NNE FETCH OF THE WINDS OVER THE LAKE HAS CONTINUED TO ALLOW FOR 20+ MPH GUSTS EARLY THIS EVE. THESE LOOK SLOW TO SUBSIDE PER OBSERVATIONAL TRENDS AND THE RAP BUFKIT SOUNDINGS. SO THESE WILL ADD A LITTLE NIP IN THE AIR...BY JUNE STANDARDS...ACROSS CHICAGO WITH TEMPS FALLING SLOWLY THROUGH THE MID-UPPER 50S. THE COOLEST TEMPS TONIGHT STILL LOOK TO BE ALONG THE STATE LINE WHERE CONDITIONS SHOULD DECOUPLE. UPPER 40S SHOULD BE REALIZED THERE. MTF && .PREV DISCUSSION... 239 PM CDT STRATUS LAYER THAT WAS ANCHORED OVER FAR NORTHEAST IL/NORTHWEST IN THIS MORNING HAS ERODED WITH THE WARM AIR HEATING THE SFC. VISIBLE IMAGERY INDICATES A FEW AREAS OF CUMULUS CLOUDS THAT HAVE DEVELOPED THIS AFTERNOON ACROSS NORTHERN IL. IN ADDITION SOME BUILDING CUMULUS CLOUDS WERE NOTED ALONG A PONTIAC TO KANKAKEE LINE...IN AN AREA OF A STRONGER THERMAL DIFFERENTIAL. HOWEVER THE LIFT MECHANISM IN THIS AREA IS MINIMAL...AND SO A FEW ISOLATED SHOWERS/THUNDERSTORMS MAY DEVELOP BUT QUICKLY DISSIPATE. ALL PRECIPITATION OVER THE CWFA WILL BE DIURNALLY DRIVEN...THUS BY SUNSET OR IMMEDIATELY AFTER SUNSET PRECIP WILL COME TO AN END. FURTHER SOUTH STRONGER INSTABILITY WAS POSITIONED ACROSS CENTRAL IL STRETCHING WEST THROUGH NORTHERN MISSOURI. MID-LVL WAVE CONTINUES TO PIVOT EAST ACROSS FAR NORTHWEST IL THIS AFTERNOON...AND WILL MAINTAIN THE NORTHEAST FLOW ACROSS MUCH OF THE CWFA. AS A RESULT COOL TEMPS WILL PERSIST THIS EVENING...WITH MINIMAL CLOUD COVER FROM THE DIFFLUENT FLOW ALOFT. SKIES WILL BECOME MOSTLY CLEAR TONIGHT...WITH THE LLVL FLOW WEAKENING. THIS SHOULD PROVIDE DECENT RADIATIONAL COOLING WITH TEMPS OVERNIGHT EXPECTED TO BE IN THE MID 50S SOUTH OF I-80. FURTHER NORTH TEMPS WILL BE MUCH COOLER TO ARND 50...POSSIBLY THE UPR 40S FOR AREAS ALONG AND NORTH OF A ROCKFORD...AURORA...WAUKEGAN LINE. CONFIDENCE...HIGH. WEDNESDAY THROUGH THURSDAY... 500MB TROUGH AXIS SLOWLY PIVOTS TO THE EASTERN GREAT LAKES WED...AND WILL CONTINUE TO PUSH EAST THUR. THE SFC RIDGE WILL ALSO BEGIN TO PUSH EAST...HOWEVER AN ONSHORE OR NORTHEAST TO EAST FLOW WILL PERSIST INTO WED FOR MUCH OF NORTHERN IL. THE DIFFERENCE FOR WED WILL BE THAT THE 850MB THERMAL TROUGH WILL LINGER OVERHEAD. WITH ABUNDANT SUNSHINE AND SFC HEATING...TEMPS SHUD WARM INTO THE MID/UPR 70S OR POSSIBLY THE LOW 80S FROM LASALLE TO IROQUOIS COUNTY. FOR THUR 500MB HEIGHTS WILL BEGIN TO RISE WITH FLOW BEGINNING TO TURN TO THE SOUTHEAST IN THE LLVLS. A WEAK LAKE BREEZE MAY DEVELOP AND PUSH INTO LAKE COUNTY IL...WHICH WOULD MOST LIKELY PROVIDE A COOLING TREND IN THE AFTN HOURS. 850MB TEMPS WILL STEADILY WARM FOR THUR TO ARND 14 TO 16 DEG C...WITH CONTINUED THIN CLOUD COVER. THIS WILL ALLOW TEMPS TO WARM INTO THE LOW/MID 80S. THE CAVEAT WILL BE AREAS OF LAKE COUNTY IL POST FRONTAL PASSAGE THAT WILL ALLOW TEMPS TO FALL INTO THE 60S IN THE AFTN. IT DOES APPEAR THAT ENOUGH DRY AIR WILL LINGER THRU THUR AFTN/EVE...THUS HAVE HELD ONTO A DRY FORECAST IN THIS TIMEFRAME. THIS PATTERN WILL BE CHANGING AS WE MIGRATE INTO THE EXTENDED PERIODS. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN DRY WEATHER THROUGH THUR...MEDIUM/HIGH. FRIDAY THROUGH MONDAY... MINIMAL CHANGES FROM PREVIOUS FORECAST IN REGARDS TO THE EXTENDED PERIODS. POSSIBLY THE FIRST STRETCH OF 90 DEG DAYS IS UPON US FOR SUN/MON/TUE. GUIDANCE HAS A WARM FRONTAL BOUNDARY LIFTING OVERHEAD FRI WITH SOUTHERLY FLOW USHERING IN ADDTL LLVL MOISTURE. IT DOES APPEAR A WAVE WILL ALSO PUSH OVER THE CWFA FRI...WITH POTENTIAL FOR SHOWERS/THUNDERSTORMS. TEMPS WILL BE SLIGHTLY WARM FOR FRI INTO THE UPR 80S...WITH A FEW 90 DEGREE POINTS ACROSS THE CWFA. ENSEMBLES FOR SEVERAL DAYS HAVE CONTINUED TO INDICATE THAT A 500MB RIDGE ACROSS THE CENTRAL CONUS WILL ADVECT EAST AND BECOME ANCHORED ACROSS THE EASTERN HALF OF THE CONUS BY THE WEEKEND AND POSSIBLY PERSIST THROUGH EARLY NEXT WEEK. ADDITIONALLY...GUIDANCE HAS PROGGED 850MB TEMPS TO RISE TO ARND 20-22 DEG C FOR THE WEEKEND THRU EARLY NEXT WEEK. CONSISTENCY FROM PREVIOUS RUNS SUGGESTS HIGH CONFIDENCE IN THIS WARM STRETCH ARRIVING. THEN SUN/MON/TUE APPEAR TO BE NEAR CARBON COPIES WITH TEMPS EASILY WARMING TO 90 DEGREES...POSSIBLY THE LOW 90S. CLIMATOLOGY BASED ON THE 850MB TEMPS PROGGED AND TIME OF YEAR WOULD SUGGEST TEMPS TO BE WARMER AS FORECASTED. A COUPLE LIMITING FACTORS MIGHT BE THE POTENTIAL FOR A SERIES OF WAVES BRINGING INSTABILITY AND THUNDERSTORM POTENTIAL EACH DAY OF THE EXTENDED...ALONG WITH DEW PTS PROGGED TO BE ARND 70 DEG. THIS COULD POTENTIALLY KEEP TEMPS IN CHECK IN THE MID/UPR 80S. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN PRECIP/CONVECTIVE FORECAST...MEDIUM/HIGH. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 00Z... * TIMING OF DIMINISHING GUSTS THIS EVENING. * WIND TRENDS TOMORROW...LIKELY VARYING BETWEEN NORTHEAST AND EAST. LENNING //DISCUSSION...UPDATED 00Z... HIGH PRESSURE SITTING OVER LAKE MICHIGAN THIS EVENING WILL VERY GRADUALLY SLIDE EAST OVER THE NEXT TWO DAYS...SLOWLY VEERING WINDS FROM NORTHEAST TO SOUTHEAST AND EVENTUALLY BY THURSDAY AROUND TO THE SOUTH. THIS PATTERN SHOULD KEEP PRECIPITATION OUT OF THE AREA FOR A WHILE AND MAINTAIN GENERALLY CLEAR AND QUIET CONDITIONS. LENNING //ORD AND MDW CONFIDENCE...UPDATED 00Z... * MEDIUM CONFIDENCE IN WIND TRENDS. HIGH CONFIDENCE IN OTHER ELEMENTS. LENNING //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... THURSDAY...VFR. FRIDAY THROUGH MONDAY...PERIODIC CHANCES FOR TSRA...OTHERWISE VFR. LENNING && .MARINE... 137 PM CDT A SURFACE RIDGE OF HIGH PRESSURE ACROSS THE UPPER GREAT LAKES REGION...WILL SHIFT EASTWARD TOWARDS NEW ENGLAND BY WEDNESDAY EVENING. MEANWHILE...LOW PRESSURE IS EXPECTED TO TAKE SHAPE ACROSS THE PLAINS STATES. THIS PRESSURE PATTERN WILL REMAIN IN PLACE FOR A FEW DAYS INTO THE WEEKEND. OVERALL...THIS WILL RESULT IN A PROLONGED PERIOD OF SOUTHERLY WINDS ACROSS THE LAKE. WIND MAGNITUDES GENERALLY LOOK TO BE IN THE 10 TO 20 KT RANGE...WITH A FEW PERIODS OF 15 TO 25 KT SOUTHERLY WINDS...ESPECIALLY LATER IN THE PERIOD. THERE WILL ALSO BE INCREASING CHANCES FOR A FEW PERIODS OF THUNDERSTORM ACTIVITY FRIDAY AND INTO THE WEEKEND OVER THE LAKE. A FAIRLY ACTIVE WEATHER PATTERN LOOKS TO SETUP UP ACROSS THE GREAT THE NORTHERN CONUS AND GREAT LAKES REGION. IN THE SHORTER TERM...I HAVE EXTENDED THE SMALL CRAFT ADVISORY INTO THIS EVENING FOR THE ILLINOIS SHORES AND MAINTAINED THE ADVISORY THROUGH LATE TONIGHT FOR THE INDIANA SHORES. LOCAL BUOY OBS INDICATE WAVES AROUND 4 FT...AND WITH THE ONSHORE FLOW CONTINUING TO BE IN THE 15 TO 20 KT RANGE AHEAD OF THE SURFACE HIGH...I DO NOT SEE ANY IMPROVEMENT IN THE WAVE CONDITIONS FOR SEVERAL MORE HOURS. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 4 AM WEDNESDAY. IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 4 AM WEDNESDAY. LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS UNTIL 10 PM TUESDAY. SMALL CRAFT ADVISORY...NEARSHORE NORTHERLY IS TO MICHIGAN CITY IN UNTIL 4 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1208 PM CDT MON JUN 17 2013 .DISCUSSION... ISSUED 1010 AM CDT MON JUN 17 2013 EARLY MORNING FOG HAS LARGELY LIFTED...WITH JUST A BIT OF HAZE LINGERING NEAR THE INDIANA BORDER. LARGE CIRRUS SHIELD SPREADING OVER MOST OF THE FORECAST AREA...ALTHOUGH A BAND OF ALTOCUMULUS IS ALONG THE I-70 CORRIDOR. THIS IS IN THE SAME GENERAL AREA AS A WEAK SURFACE BOUNDARY...AND IS THE MOST LIKELY LOCATION FOR ANY CONVECTION TO DEVELOP...MAINLY DURING THE AFTERNOON HOURS. WITH A BROAD POOL OF DEW POINTS NEAR 70 ALONG THE I-72 CORRIDOR... SCATTERED STORMS ARE ALSO POSSIBLE THERE WITH THE BOUNDARY NOT TOO FAR AWAY...BUT THEY SHOULD NOT BE THAT ORGANIZED. ANOTHER BOUNDARY DROPPING INTO THE NORTHWEST PART OF THE FORECAST AREA MAY ALSO TRIGGER A COUPLE SHOWERS/STORMS THIS AFTERNOON AS WELL IN THAT AREA. HAVE SENT SOME UPDATED ZONES/GRIDS...MAINLY TO UPDATE THE PRECIPITATION TRENDS. GEELHART && .AVIATION... ISSUED 1204 PM CDT MON JUN 17 2013 MAIN CONCERN WITH 18Z TAF SET INVOLVES POTENTIAL FOR POP-UP CONVECTION. MIDDAY SURFACE MAP SHOWS A COUPLE WEAK BOUNDARIES OVER CENTRAL ILLINOIS AND LATEST VISIBLE SATELLITE SHOWING CUMULUS STARTING TO DEVELOP ALONG THEM. THE BOUNDARIES SHOULD NOT MOVE MUCH DURING THE AFTERNOON...BUT DRIER AIR IS SPREADING SOUTHWARD TOWARD THEM. THUS...AM THINKING THAT ONLY KSPI/KDEC/KCMI MAY SEE A THREAT OF THUNDER THIS AFTERNOON...AS THEY ARE CLOSEST TO THE BOUNDARY. COVERAGE CURRENTLY NOT EXPECTED TO BE ENOUGH TO WARRANT MORE THAN A VCTS MENTION AT THESE SITES. ANY THUNDER NEAR THE TAF SITES SHOULD FADE WITH SUNSET. LATE IN THE PERIOD...MAY SEE SOME MVFR CONDITIONS AT TIMES JUST BEFORE SUNRISE...BUT DO NOT THINK IT WILL GET AS WIDESPREAD OR DENSE AS THIS MORNING...DUE TO HIGHER RANGES BETWEEN TEMPERATURE AND DEW POINT. GEELHART && .PREV DISCUSSION... ISSUED 252 AM CDT MON JUN 17 2013 SHORT TERM...TODAY THROUGH WEDNESDAY VERY WEAK SURFACE BOUNDARY EXTENDING ACROSS SOUTH-CENTRAL ILLINOIS WILL BE THE PRIMARY FOCUSING MECHANISM FOR SCATTERED THUNDERSTORMS TODAY. WITH ONE UPPER-WAVE PASSING WELL TO THE NORTH ACROSS THE GREAT LAKES AND ANOTHER TRACKING TO THE S/SW INTO THE LOWER OHIO RIVER VALLEY...VERY LITTLE UPPER SUPPORT WILL BE IN PLACE FOR WIDESPREAD CONVECTION ACROSS CENTRAL ILLINOIS. DESPITE LACK OF UPPER DYNAMICS...VERY MOIST AIR MASS IN PRESENCE OF WEAK SURFACE FORCING WILL BE ENOUGH TO TRIGGER A FEW SHOWERS/THUNDERSTORMS LATER TODAY. HRRR SUGGESTS DEVELOPMENT AROUND MIDDAY...ESPECIALLY IN CLOSER PROXIMITY TO BOUNDARY. WILL THEREFORE INCLUDE LOW CHANCE POPS TODAY...WITH BEST RAIN CHANCES SOUTH OF I-72. SHORT-WAVE TROUGH CURRENTLY EVIDENT ON WATER VAPOR IMAGERY OVER SOUTHERN SASKATCHEWAN MAY PROVIDE A NEW WRINKLE IN THE FORECAST FOR TUESDAY. WHILE WE PREVIOUSLY THOUGHT TUESDAY WOULD BE DRY...LATEST MODEL GUIDANCE IS INDICATING THE POTENTIAL FOR ISOLATED CONVECTION DURING THE AFTERNOON. THANKS TO A CONTINUED MOIST AIR MASS AND THE ARRIVAL OF MODEST UPPER FORCING DURING PEAK HEATING...HAVE INCLUDED A SLIGHT CHANCE FOR THUNDER TUESDAY AFTERNOON. ONCE THE WAVE PUSHES FURTHER EAST...SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION FOR TUESDAY NIGHT AND WEDNESDAY...PROVIDING SEASONABLY WARM AND DRY CONDITIONS. LONG TERM...THURSDAY THROUGH SUNDAY 00Z 17 JUN MODELS CONTINUE TO SUGGEST A VERY WARM AND LARGELY DRY EXTENDED FORECAST. ALL MODELS BUILD AN UPPER-LEVEL RIDGE ACROSS THE PLAINS ON THURSDAY...THEN SHIFT IT INTO THE MIDWEST OVER THE WEEKEND. PREVIOUS RUNS DISAGREED ON THE EXACT STRENGTH/POSITIONING OF THE RIDGE...WHICH BROUGHT INTO QUESTION WHETHER ANY MCS ACTIVITY COULD RIDE UP/OVER THE RIDGE INTO THE AREA DURING THE PERIOD. LATEST GFS/ECMWF/GEM ARE ALL LOOKING STRONGER WITH THE RIDGING...KEEPING BEST FORCING FOR NOCTURNAL MCS DEVELOPMENT FURTHER NORTH ACROSS THE UPPER MIDWEST INTO THE GREAT LAKES. MODELS INDICATE ONE CONVECTIVE COMPLEX MAY BRUSH THE KILX CWA TO THE NORTH FRIDAY NIGHT...BEFORE RIDGE BUILDS EVEN FURTHER ON SATURDAY. HAVE THEREFORE INCLUDED CHANCE POPS ALONG AND NORTH OF A CANTON TO BLOOMINGTON LINE FRIDAY NIGHT...BUT HAVE GONE WITH A DRY FORECAST ACROSS THE BOARD FOR THE REMAINDER OF THE EXTENDED. WILL LIKELY HAVE TO WAIT UNTIL RIDGE BEGINS TO FLATTEN EARLY NEXT WEEK BEFORE ANY WIDESPREAD RAIN CHANCES RETURN TO THE AREA. GIVEN BUILDING UPPER HEIGHTS AND LACK OF CONVECTION...HIGH TEMPERATURES WILL REACH THE UPPER 80S/LOWER 90S WHILE OVERNIGHT LOWS ONLY DROP INTO THE LOWER 70S FRIDAY THROUGH SUNDAY. BARNES && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1012 AM CDT MON JUN 17 2013 .DISCUSSION... ISSUED 1010 AM CDT MON JUN 17 2013 EARLY MORNING FOG HAS LARGELY LIFTED...WITH JUST A BIT OF HAZE LINGERING NEAR THE INDIANA BORDER. LARGE CIRRUS SHIELD SPREADING OVER MOST OF THE FORECAST AREA...ALTHOUGH A BAND OF ALTOCUMULUS IS ALONG THE I-70 CORRIDOR. THIS IS IN THE SAME GENERAL AREA AS A WEAK SURFACE BOUNDARY...AND IS THE MOST LIKELY LOCATION FOR ANY CONVECTION TO DEVELOP...MAINLY DURING THE AFTERNOON HOURS. WITH A BROAD POOL OF DEW POINTS NEAR 70 ALONG THE I-72 CORRIDOR... SCATTERED STORMS ARE ALSO POSSIBLE THERE WITH THE BOUNDARY NOT TOO FAR AWAY...BUT THEY SHOULD NOT BE THAT ORGANIZED. ANOTHER BOUNDARY DROPPING INTO THE NORTHWEST PART OF THE FORECAST AREA MAY ALSO TRIGGER A COUPLE SHOWERS/STORMS THIS AFTERNOON AS WELL IN THAT AREA. HAVE SENT SOME UPDATED ZONES/GRIDS...MAINLY TO UPDATE THE PRECIPITATION TRENDS. GEELHART && .AVIATION... ISSUED 645 AM CDT MON JUN 17 2013 AREAS OF FOG WITH IFR TO MVFR CONDITIONS AT PIA AND BMI...LOCALLY DENSE ALONG I-72 AT SPI...DEC AND CMI WITH LIFR TO VLIFR CONDITIONS...TO OCCUR UNTIL 13Z/8 AM WITH FOG LIFTING BEFORE 14Z/9 AM. SCATTERED CUMULUS CLOUDS OF 3-5K FT TO DEVELOP LATER THIS MORNING AND AFTERNOON WITH SCATTERED-BROKEN CIRRUS CLOUDS AT 25K FT. ISOLATED SHOWERS AND THUNDERSTORMS TO DEVELOP MAINLY SOUTH OF I-72 THIS AFTERNOON NEAR A WEAK BOUNDARY AND BE CLOSEST IMPACT TO SPI AND DEC AIRPORTS WHERE VCSH. SCATTERED CUMULUS CLOUDS DISSIPATE AT SUNSET WITH SCATTERED CIRRUS CLOUDS. COULD BE PATCHY FOG AGAIN OVERNIGHT WITH MVFR VSBYS POSSIBLE AFTER 07Z BUT NOT AS WIDESPREAD AS EARLY THIS MORNING SINCE LARGER TEMPERATURE/DEWPOINT SPREADS EXPECTED. WINDS TO REMAIN FAIRLY LIGHT UNDER 10 KTS NEXT 24 HOURS...WITH LIGHT AND VARIABLE TO CALM WINDS EARLY THIS MORNING BECOMING WSW 5-7 KTS BY AFTERNOON AND DIMINISHING LIGHT AGAIN AFTER SUNSET TONIGHT. 07 && .PREV DISCUSSION... ISSUED 252 AM CDT MON JUN 17 2013 SHORT TERM...TODAY THROUGH WEDNESDAY VERY WEAK SURFACE BOUNDARY EXTENDING ACROSS SOUTH-CENTRAL ILLINOIS WILL BE THE PRIMARY FOCUSING MECHANISM FOR SCATTERED THUNDERSTORMS TODAY. WITH ONE UPPER-WAVE PASSING WELL TO THE NORTH ACROSS THE GREAT LAKES AND ANOTHER TRACKING TO THE S/SW INTO THE LOWER OHIO RIVER VALLEY...VERY LITTLE UPPER SUPPORT WILL BE IN PLACE FOR WIDESPREAD CONVECTION ACROSS CENTRAL ILLINOIS. DESPITE LACK OF UPPER DYNAMICS...VERY MOIST AIR MASS IN PRESENCE OF WEAK SURFACE FORCING WILL BE ENOUGH TO TRIGGER A FEW SHOWERS/THUNDERSTORMS LATER TODAY. HRRR SUGGESTS DEVELOPMENT AROUND MIDDAY...ESPECIALLY IN CLOSER PROXIMITY TO BOUNDARY. WILL THEREFORE INCLUDE LOW CHANCE POPS TODAY...WITH BEST RAIN CHANCES SOUTH OF I-72. SHORT-WAVE TROUGH CURRENTLY EVIDENT ON WATER VAPOR IMAGERY OVER SOUTHERN SASKATCHEWAN MAY PROVIDE A NEW WRINKLE IN THE FORECAST FOR TUESDAY. WHILE WE PREVIOUSLY THOUGHT TUESDAY WOULD BE DRY...LATEST MODEL GUIDANCE IS INDICATING THE POTENTIAL FOR ISOLATED CONVECTION DURING THE AFTERNOON. THANKS TO A CONTINUED MOIST AIR MASS AND THE ARRIVAL OF MODEST UPPER FORCING DURING PEAK HEATING...HAVE INCLUDED A SLIGHT CHANCE FOR THUNDER TUESDAY AFTERNOON. ONCE THE WAVE PUSHES FURTHER EAST...SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION FOR TUESDAY NIGHT AND WEDNESDAY...PROVIDING SEASONABLY WARM AND DRY CONDITIONS. LONG TERM...THURSDAY THROUGH SUNDAY 00Z 17 JUN MODELS CONTINUE TO SUGGEST A VERY WARM AND LARGELY DRY EXTENDED FORECAST. ALL MODELS BUILD AN UPPER-LEVEL RIDGE ACROSS THE PLAINS ON THURSDAY...THEN SHIFT IT INTO THE MIDWEST OVER THE WEEKEND. PREVIOUS RUNS DISAGREED ON THE EXACT STRENGTH/POSITIONING OF THE RIDGE...WHICH BROUGHT INTO QUESTION WHETHER ANY MCS ACTIVITY COULD RIDE UP/OVER THE RIDGE INTO THE AREA DURING THE PERIOD. LATEST GFS/ECMWF/GEM ARE ALL LOOKING STRONGER WITH THE RIDGING...KEEPING BEST FORCING FOR NOCTURNAL MCS DEVELOPMENT FURTHER NORTH ACROSS THE UPPER MIDWEST INTO THE GREAT LAKES. MODELS INDICATE ONE CONVECTIVE COMPLEX MAY BRUSH THE KILX CWA TO THE NORTH FRIDAY NIGHT...BEFORE RIDGE BUILDS EVEN FURTHER ON SATURDAY. HAVE THEREFORE INCLUDED CHANCE POPS ALONG AND NORTH OF A CANTON TO BLOOMINGTON LINE FRIDAY NIGHT...BUT HAVE GONE WITH A DRY FORECAST ACROSS THE BOARD FOR THE REMAINDER OF THE EXTENDED. WILL LIKELY HAVE TO WAIT UNTIL RIDGE BEGINS TO FLATTEN EARLY NEXT WEEK BEFORE ANY WIDESPREAD RAIN CHANCES RETURN TO THE AREA. GIVEN BUILDING UPPER HEIGHTS AND LACK OF CONVECTION...HIGH TEMPERATURES WILL REACH THE UPPER 80S/LOWER 90S WHILE OVERNIGHT LOWS ONLY DROP INTO THE LOWER 70S FRIDAY THROUGH SUNDAY. BARNES && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
645 AM CDT MON JUN 17 2013 .DISCUSSION... ISSUED 252 AM CDT MON JUN 17 2013 SHORT TERM...TODAY THROUGH WEDNESDAY VERY WEAK SURFACE BOUNDARY EXTENDING ACROSS SOUTH-CENTRAL ILLINOIS WILL BE THE PRIMARY FOCUSING MECHANISM FOR SCATTERED THUNDERSTORMS TODAY. WITH ONE UPPER-WAVE PASSING WELL TO THE NORTH ACROSS THE GREAT LAKES AND ANOTHER TRACKING TO THE S/SW INTO THE LOWER OHIO RIVER VALLEY...VERY LITTLE UPPER SUPPORT WILL BE IN PLACE FOR WIDESPREAD CONVECTION ACROSS CENTRAL ILLINOIS. DESPITE LACK OF UPPER DYNAMICS...VERY MOIST AIRMASS IN PRESENCE OF WEAK SURFACE FORCING WILL BE ENOUGH TO TRIGGER A FEW SHOWERS/THUNDERSTORMS LATER TODAY. HRRR SUGGESTS DEVELOPMENT AROUND MIDDAY...ESPECIALLY IN CLOSER PROXIMITY TO BOUNDARY. WILL THEREFORE INCLUDE LOW CHANCE POPS TODAY...WITH BEST RAIN CHANCES SOUTH OF I-72. SHORT-WAVE TROUGH CURRENTLY EVIDENT ON WATER VAPOR IMAGERY OVER SOUTHERN SASKATCHEWAN MAY PROVIDE A NEW WRINKLE IN THE FORECAST FOR TUESDAY. WHILE WE PREVIOUSLY THOUGHT TUESDAY WOULD BE DRY...LATEST MODEL GUIDANCE IS INDICATING THE POTENTIAL FOR ISOLATED CONVECTION DURING THE AFTERNOON. THANKS TO A CONTINUED MOIST AIRMASS AND THE ARRIVAL OF MODEST UPPER FORCING DURING PEAK HEATING...HAVE INCLUDED A SLIGHT CHANCE FOR THUNDER TUESDAY AFTERNOON. ONCE THE WAVE PUSHES FURTHER EAST...SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION FOR TUESDAY NIGHT AND WEDNESDAY...PROVIDING SEASONABLY WARM AND DRY CONDITIONS. LONG TERM...THURSDAY THROUGH SUNDAY 00Z 17 JUN MODELS CONTINUE TO SUGGEST A VERY WARM AND LARGELY DRY EXTENDED FORECAST. ALL MODELS BUILD AN UPPER-LEVEL RIDGE ACROSS THE PLAINS ON THURSDAY...THEN SHIFT IT INTO THE MIDWEST OVER THE WEEKEND. PREVIOUS RUNS DISAGREED ON THE EXACT STRENGTH/POSITIONING OF THE RIDGE...WHICH BROUGHT INTO QUESTION WHETHER ANY MCS ACTIVITY COULD RIDE UP/OVER THE RIDGE INTO THE AREA DURING THE PERIOD. LATEST GFS/ECMWF/GEM ARE ALL LOOKING STRONGER WITH THE RIDGING...KEEPING BEST FORCING FOR NOCTURNAL MCS DEVELOPMENT FURTHER NORTH ACROSS THE UPPER MIDWEST INTO THE GREAT LAKES. MODELS INDICATE ONE CONVECTIVE COMPLEX MAY BRUSH THE KILX CWA TO THE NORTH FRIDAY NIGHT...BEFORE RIDGE BUILDS EVEN FURTHER ON SATURDAY. HAVE THEREFORE INCLUDED CHANCE POPS ALONG AND NORTH OF A CANTON TO BLOOMINGTON LINE FRIDAY NIGHT...BUT HAVE GONE WITH A DRY FORECAST ACROSS THE BOARD FOR THE REMAINDER OF THE EXTENDED. WILL LIKELY HAVE TO WAIT UNTIL RIDGE BEGINS TO FLATTEN EARLY NEXT WEEK BEFORE ANY WIDESPREAD RAIN CHANCES RETURN TO THE AREA. GIVEN BUILDING UPPER HEIGHTS AND LACK OF CONVECTION...HIGH TEMPERATURES WILL REACH THE UPPER 80S/LOWER 90S WHILE OVERNIGHT LOWS ONLY DROP INTO THE LOWER 70S FRIDAY THROUGH SUNDAY. && .AVIATION... ISSUED 645 AM CDT MON JUN 17 2013 AREAS OF FOG WITH IFR TO MVFR CONDITIONS AT PIA AND BMI...LOCALLY DENSE ALONG I-72 AT SPI...DEC AND CMI WITH LIFR TO VLIFR CONDITIONS...TO OCCUR UNTIL 13Z/8 AM WITH FOG LIFTING BEFORE 14Z/9 AM. SCATTERED CUMULUS CLOUDS OF 3-5K FT TO DEVELOP LATER THIS MORNING AND AFTEROON WITH SCATTERED-BROKEN CIRRUS CLOUDS AT 25K FT. ISOLATED SHOWERS AND THUNDERSTORMS TO DEVELOP MAINLY SOUTH OF I-72 THIS AFTERNOON NEAR A WEAK BOUNDARY AND BE CLOSEST IMPACT TO SPI AND DEC AIRPORTS WHERE VCSH. SCATTERED CUMULUS CLOUDS DISSIPATE AT SUNSET WITH SCATTERED CIRRUS CLOUDS. COULD BE PATCHY FOG AGAIN OVERNIGHT WITH MVFR VSBYS POSSIBLE AFTER 07Z BUT NOT AS WIDESPREAD AS EARLY THIS MORNING SINCE LARGER TEMPERATURE/DEWPOINT SPREADS EXPECTED. WINDS TO REMAIN FAIRLY LIGHT UNDER 10 KTS NEXT 24 HOURS...WITH LIGHT AND VARIABLE TO CALM WINDS EARLY THIS MORNING BECOMING WSW 5-7 KTS BY AFTERNOON AND DIMINISHING LIGHT AGAIN AFTER SUNSET TONIGHT. 07 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
252 AM CDT MON JUN 17 2013 .DISCUSSION... ISSUED 252 AM CDT MON JUN 17 2013 SHORT TERM...TODAY THROUGH WEDNESDAY VERY WEAK SURFACE BOUNDARY EXTENDING ACROSS SOUTH-CENTRAL ILLINOIS WILL BE THE PRIMARY FOCUSING MECHANISM FOR SCATTERED THUNDERSTORMS TODAY. WITH ONE UPPER-WAVE PASSING WELL TO THE NORTH ACROSS THE GREAT LAKES AND ANOTHER TRACKING TO THE S/SW INTO THE LOWER OHIO RIVER VALLEY...VERY LITTLE UPPER SUPPORT WILL BE IN PLACE FOR WIDESPREAD CONVECTION ACROSS CENTRAL ILLINOIS. DESPITE LACK OF UPPER DYNAMICS...VERY MOIST AIRMASS IN PRESENCE OF WEAK SURFACE FORCING WILL BE ENOUGH TO TRIGGER A FEW SHOWERS/THUNDERSTORMS LATER TODAY. HRRR SUGGESTS DEVELOPMENT AROUND MIDDAY...ESPECIALLY IN CLOSER PROXIMITY TO BOUNDARY. WILL THEREFORE INCLUDE LOW CHANCE POPS TODAY...WITH BEST RAIN CHANCES SOUTH OF I-72. SHORT-WAVE TROUGH CURRENTLY EVIDENT ON WATER VAPOR IMAGERY OVER SOUTHERN SASKATCHEWAN MAY PROVIDE A NEW WRINKLE IN THE FORECAST FOR TUESDAY. WHILE WE PREVIOUSLY THOUGHT TUESDAY WOULD BE DRY...LATEST MODEL GUIDANCE IS INDICATING THE POTENTIAL FOR ISOLATED CONVECTION DURING THE AFTERNOON. THANKS TO A CONTINUED MOIST AIRMASS AND THE ARRIVAL OF MODEST UPPER FORCING DURING PEAK HEATING...HAVE INCLUDED A SLIGHT CHANCE FOR THUNDER TUESDAY AFTERNOON. ONCE THE WAVE PUSHES FURTHER EAST...SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION FOR TUESDAY NIGHT AND WEDNESDAY...PROVIDING SEASONABLY WARM AND DRY CONDITIONS. LONG TERM...THURSDAY THROUGH SUNDAY 00Z 17 JUN MODELS CONTINUE TO SUGGEST A VERY WARM AND LARGELY DRY EXTENDED FORECAST. ALL MODELS BUILD AN UPPER-LEVEL RIDGE ACROSS THE PLAINS ON THURSDAY...THEN SHIFT IT INTO THE MIDWEST OVER THE WEEKEND. PREVIOUS RUNS DISAGREED ON THE EXACT STRENGTH/POSITIONING OF THE RIDGE...WHICH BROUGHT INTO QUESTION WHETHER ANY MCS ACTIVITY COULD RIDE UP/OVER THE RIDGE INTO THE AREA DURING THE PERIOD. LATEST GFS/ECMWF/GEM ARE ALL LOOKING STRONGER WITH THE RIDGING...KEEPING BEST FORCING FOR NOCTURNAL MCS DEVELOPMENT FURTHER NORTH ACROSS THE UPPER MIDWEST INTO THE GREAT LAKES. MODELS INDICATE ONE CONVECTIVE COMPLEX MAY BRUSH THE KILX CWA TO THE NORTH FRIDAY NIGHT...BEFORE RIDGE BUILDS EVEN FURTHER ON SATURDAY. HAVE THEREFORE INCLUDED CHANCE POPS ALONG AND NORTH OF A CANTON TO BLOOMINGTON LINE FRIDAY NIGHT...BUT HAVE GONE WITH A DRY FORECAST ACROSS THE BOARD FOR THE REMAINDER OF THE EXTENDED. WILL LIKELY HAVE TO WAIT UNTIL RIDGE BEGINS TO FLATTEN EARLY NEXT WEEK BEFORE ANY WIDESPREAD RAIN CHANCES RETURN TO THE AREA. GIVEN BUILDING UPPER HEIGHTS AND LACK OF CONVECTION...HIGH TEMPERATURES WILL REACH THE UPPER 80S/LOWER 90S WHILE OVERNIGHT LOWS ONLY DROP INTO THE LOWER 70S FRIDAY THROUGH SUNDAY. BARNES && .AVIATION... ISSUED 1150 PM CDT SUN JUN 16 2013 FOG HAS ALREADY STARTED TO DEVELOP ACROSS THE AREA AND CMI IS ALREADY AT 4SM. BELIEVE THIS WILL CONTINUE AND AM EXPECTING THE REMAINDER OF THE TAF SITES TO HAVE MVFR VIS STARTING AT 06Z OR SHORTLY THEREAFTER. THIS MVFR VIS WILL LIKELY HOLD TIL CLOSE TO SUNRISE AND THEN ALL TAF SITES WILL SEE TEMPO VIS DOWN TO IFR OF 1-2SM. AFTER SUNRISE FOG WILL DISSIPATE QUICKLY AND NOT EXPECTING ANY VIS ISSUES REMAINDER OF THE TAF PERIOD. HIGH CIRRUS WILL BE THE ONLY CLOUD AROUND OVERNIGHT. THEN CU WILL DEVELOP TOMORROW MORNING AT AROUND 4-5KFT AND THEN DISSIPATE AROUND SUNSET...LEAVING CLEAR SKIES TOMORROW EVENING. WINDS WILL BE LIGHT OVERNIGHT AND THEN WESTERLY TOMORROW...LESS THAN 10KTS. THEN LIGHT OUT OF THE WEST AGAIN TOMORROW EVENING. AUTEN && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
245 PM MDT MON JUN 17 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 245 PM MDT MON JUN 17 2013 EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW OVER CWA WITH H5 RIDGE ACROSS WESTERN US. AT THE SURFACE A FRONT CURRENTLY...WITH AREA OF SURFACE CONVERGENCE JUST WEST OUR OUR CWA WHERE ISOLATED THUNDERSTORMS ARE BEGGING TO INTENSIFY. LATEST RAP ANALYSIS INDICATES MIXED LAYER CAPE IN EXCESS OF 1500 J/KG OVER OUR CWA AND SHOWS THIS INCREASING AS LAPSE RATES CONTINUE TO STEEPEN. LATEST HRRR SHOWS THUNDERSTORM ACTIVITY OVER EASTERN COLORADO EXPANDING IN COVERAGE AND MOVING EAST THROUGH THE AFTERNOON. NAM CONTINUES TO SHOW WIDESPREAD CONVECTIVELY INDUCED QPF IN PLACE THROUGH THE EVENING OVERSPREADING THE CWA AND THEN LINGERING OVERNIGHT AS A SHORTWAVE TROUGH UPSTREAM PUSHES SOUTH. GFS/SREF SHOW A SIMILAR PATTERN...THOUGH QPF AMOUNTS ARE NOT QUITE AS HIGH. SHEER PROFILES SHOULD IMPROVE THROUGH THE AFTERNOON/EVENING WITH 0-6KM BULK SHEER 30-40KT...WHICH SHOULD SUPPORT SEVERE THUNDERSTORMS. EARLY ON THIS AFTERNOON/EVENING TORNADOES MAY BE POSSIBLE WITH STEEP LAPSE RATES IN PROXIMITY TO SURFACE BOUNDARY/THUNDERSTORM INTERACTIONS. AIR MASS CONTINUES TO BE VERY MOIST...AND CONSIDERING THE VERY SLOW STORM MOTION (5-10KT 0-6KM MEAN WIND) WE COULD SEE ISOLATED FLASH FLOOD RISK WITH THIS ACTIVITY. AT THE VERY LEAST MOST LOCATIONS COULD SEE WIDESPREAD 0.5 TO 1.00" RAINFALL. CURRENTLY THINKING WE SHOULD SEE AFTERNOON THUNDERSTORM ACTIVITY MERGING INTO AT LEAST ONE CLUSTER/LINE AND SPREAD EAST THROUGH THE EVENING...BEFORE ADDITIONAL ACTIVITY DEVELOPS WITH OVERNIGHT SHORTWAVE. I ONLY MADE MINOR CHANGES TO INHERITED POP FORECAST WITH MAIN CHANGE TO END THUNDERSTORM CHANCES EARLY TUE MORNING AS WE SHOULD BE SUBSIDENT ON BACK SIDE OF DEPARTING PV ANOMALY. GUIDANCE SUPPORTS THUNDERSTORMS REDEVELOPING BY WED AFTERNOON FROM THE WEST TO THE EAST. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 210 PM MDT MON JUN 17 2013 A RIDGE WILL MOVE INTO THE PLAINS AND REMAIN THROUGH THURSDAY. SURFACE HIGH PRESSURE WILL BE OVER THE CENTRAL PLAINS TUESDAY NIGHT. LOW PRESSURE OVER WYOMING WEDNESDAY WILL DEVELOP SOUTH INTO EASTERN COLORADO WEDNESDAY NIGHT. BY THURSDAY A TROUGH WILL BE POSITIONED OVER NORTHWEST KANSAS, STORMS WILL LIKELY FORM OVER EASTERN COLORADO EACH AFTERNOON THROUGH WEDNESDAY DUE TO CONVERGENCE AND PROXIMITY TO THE SURFACE TROUGH. MOISTURE AND INSTABILITY WILL BE FOCUSED IN THAT AREA. PLAN TO GO WITH CHANCE POPS IN THAT AREA AND TO THE EAST WHERE STEERING WINDS WILL MOVE THE STORMS. GENERALLY LOWER POPS WILL BE USED IN THE EASTERN FA. THE TROUGH SHOULD BE EAST OF THE FA THURSDAY SO PLAN TO CONTINUE THE DRY FORECAST/NIL POPS FOR THAT PERIOD. MIN TEMPERATURES TUESDAY AND WEDNESDAY NIGHTS WILL BE IN THE LOWER TO MID 60S. MAX TEMPERATURES WEDNESDAY WILL REACH THE MID/UPPER 80S. 850 TEMPERATURES AROUND 30 WILL SUPPORT MID 90S FOR MAX TEMPERATURES THURSDAY. IN THE EXTENDED...(THURSDAY NIGHT THROUGH MONDAY)...UPPER FLOW WILL BE SOUTHWEST THROUGH THIS PART OF THE FORECAST. A SURFACE TROUGH WILL BE NEAR THE COLORADO BORDER AS WELL. IMPULSES MOVING THROUGH THE FLOW WILL PRODUCE AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS FROM FRIDAY NIGHT THROUGH SUNDAY NIGHT. THE FORECAST WILL BE DRY WITH NIL POPS THURSDAY NIGHT AND MONDAY. MIN TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S WEST TO THE UPPER 60S TO 70 EAST. MAX TEMPERATURES WILL RANGE IN THE 90S WITH SOME UPPER 80S WEST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1144 AM MDT MON JUN 17 2013 PRIMARY AVIATION CONCERN THROUGH MOST OF THE TAF PERIOD WILL BE POSSIBILITY OF STRONG THUNDERSTORMS AT BOTH KGLD AND KCMK TERMINALS. CURRENTLY EXPECT ACTIVITY TO DEVELOP ACROSS EASTERN COLORADO AND SPREAD EASTWARD THIS AFTERNOON...WITH ISOLATED THUNDERSTORMS POSSIBLY DEVELOPING WITHIN VICINITY OF BOTH TERMINALS EARLIER. BETTER CONFIDENCE IS AFTER 20Z WHEN I HAVE VCTS GROUP. I AM NOT SURE IF CONDITIONS WILL PREVAIL THOUGH THIS IS A POSSIBILITY IF A LARGE SLOW MOVING COMPLEX OF THUNDERSTORMS MOVES OVER EITHER TERMINAL. I KEPT TEMPO GROUPS FOR NOW...AND WILL NEED TO MONITOR/AMEND AS THE SITUATION EVOLVES. SOME GUIDANCE KEEPS THUNDERSTORMS LINGERING MOST OF THE NIGHT...AND WHILE I COULDNT RULE THIS OUT CONFIDENCE IS TOO LOW TO CARRY MENTION PAST 08Z (ESPECIALLY AT KMCK). WITH VERY MOIST AIRMASS IN PLACE...AND POSSIBLE INTRODUCTION OF ADDITIONAL MOISTURE FROM THUNDERSTORMS WE COULD SEE FOG/STRATUS DEVELOPMENT AFTER 09Z AT BOTH TERMINALS. IF THUNDERSTORMS LINGER THIS LIKELY WONT BE THE CASE...SO I KEPT MVFR MENTION AT BOTH TERMINALS IMPROVING AFTER DAYBREAK. A LOT CAN CHANGE WITH THIS PATTERN DUE TO TIMING/EVOLUTION OF THUNDERSTORM ACTIVITY. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...FS AVIATION...DR
AREA FORECAST DISCUSSION
NWS WICHITA KS
1246 AM CDT MON JUN 17 2013 .UPDATE... ISSUED AT 718 PM CDT SUN JUN 16 2013 SVR TSRA THAT WERE PROLIFIC GOLFBALL-SIZED HAIL PRODUCERS OVER COWLEY COUNTY HAVE DISSIPATED BUT HAVE ALSO UNLEASHED A W-NW MOVG OUTFLOW BOUNDARY ACROSS SUMNER & HARPER COUNTIES & TOWARD KICT. A CELLS HAVE DEVELOPED E OF THE OUTFLOW. ISOLD CELLS HAVE ALSO DEVELOPED OVER THE SE CORNER OF KS AS WELL AS OVER EC KS. MID-LVL FLOW IS VERY WEAK & AS SUCH FAVORS A RATHER CHAOTIC CONVECTIVE "PATTERN" FOR THE REST OF THE EVENING. HAVE TEMPORARILY ASSIGNED 40-50% TSRA TO EXTREME SC-SE KS WITH SHARP POP-GRADIENT N TOWARD KS TURNPIKE TIL 10 PM. HAVE ALSO ADJUSTED TSRA PROBABILITIES FOR LATER THIS EVENING TO REFLECT ONSET OF MCS THAT`LL SURGE SE TOWARD...THEN ACROSS...PRIMARILY SC KS. POP GAME PLAN FROM MID-NGT TO 7 AM APPEARS ON TARGET. MADE MINOR ADJUSTMENTS TO SKY GRIDS FOR EARLY THIS EVENING. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 311 PM CDT SUN JUN 16 2013 A RATHER COMPLICATED SCENARIO IS UNDERWAY ACROSS THE CENTRAL PLAINS THIS AFTERNOON. AN OUTFLOW BOUNDARY WAS LOCATED ACROSS CENTRAL KANSAS FROM NEAR KHUT EXTENDING NORTH AND WEST TOWARD NORTON KANSAS AT 2 PM CDT. CU HAS DEVELOPED ON THE COOL SIDE OF THIS OUTFLOW BOUNDARY WHILE THE OPERATIONAL ECM RAP SHOWS MINIMAL CINH WITHIN AN AXIS OF 2000-2500 J/KG. THIS BOUNDARY MAY BECOME A FOCUS FOR DEEP MOIST CONVECTION BY LATE AFTERNOON. ANOTHER DIFFUSE OUTFLOW BOUNDARY WAS SITUATED NEAR THE OKLAHOMA STATE LINE WHERE WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE ESPECIALLY SOUTH OF THE STATE LINE. FURTHER NORTH AND WEST ANOTHER OUTFLOW BOUNDARY WAS SURGING SOUTH ACROSS WESTERN NEBRASKA WHILE HIGH-BASED THUNDERSTORMS WERE DEVELOPING ACROSS THE FRONT RANGE DOWNSTREAM OF A PV ANOMALY TRANSLATING EASTWARD ACROSS THE CENTRAL ROCKIES. THE LATEST 12Z SUITE OF MODEL DATA HAS SHIFTED THE QPF AXIS A BIT FURTHER WEST TONIGHT...HOWEVER THIS AREA REMAINS OVERTURNED FROM DEEP MOIST CONVECTION LAST NIGHT/EARLY TODAY. ANY ACTIVITY DEVELOPING ALONG THE OUTFLOW BOUNDARY ACROSS CENTRAL KANSAS WOULD BE STEERED TOWARD SOUTH CENTRAL KANSAS THIS EVENING WHILE ANOTHER LINE OF SHOWERS AND THUNDERSTORMS MAY PROPAGATE SOUTHEASTWARD OFF THE HIGH PLAINS OF WESTERN KANSAS LATE TONIGHT WHILE MERGING WITH THE ACTIVITY DRIFTING SOUTH OUT OF NEBRASKA. WILL MAINTAIN HIGH POPS ACROSS MUCH OF CENTRAL/SOUTH CENTRAL KANSAS TONIGHT WHILE THE THREAT FOR FLOODING OVER SOUTHEAST KANSAS APPEARS TO HAVE DIMINISHED SLIGHTLY...HOWEVER NO PLANS TO REMOVE THE FLOOD WATCH AT THIS TIME GIVEN RAINFALL AMOUNTS BETWEEN 2-3 INCHES A FEW LOCATIONS. MAINTAINED POPS ACROSS MAINLY SOUTHEAST KANSAS THROUGH EARLY AFTERNOON ON MONDAY WITH SOME TIMING DIFFERENCES...HOWEVER BY LATE AFTERNOON TEMPERATURES ARE EXPECTED RECOVER INTO THE LOW TO MID 80S WITHIN A STABLE AIRMASS BEHIND THE DEPARTING MCS. THERE IS SOME CONCERN FOR CONTINUED OVERNIGHT CONVECTION MOVING EASTWARD OFF THE HIGH PLAINS MONDAY NIGHT AND AGAIN ON TUESDAY NIGHT ACROSS MAINLY CENTRAL KANSAS. HOWEVER BETTER CHANCES FOR DEEP MOIST CONVECTION MAY ARRIVE TOWARD THE MIDDLE OF THE WEEK AS A MORE ROBUST SHORTWAVE TROUGH MOVES OVER THE CENTRAL AND NORTHERN PLAINS. SEASONABLE TEMPERATURES ARE EXPECTED THROUGH THE PERIOD WITH HIGHS IN THE 80S AND LOW IN THE 60S. -MCGUIRE .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 311 PM CDT SUN JUN 16 2013 LINGERING SHOWERS AND THUNDERSTORMS ARE POSSIBLE FOR THE EASTERN THIRD OF KANSAS ON THURSDAY AS A SHORTWAVE EXITS THE AREA. A RIDGE OVER THE CENTRAL U.S. WILL STAY PLANTED FOR MOST OF THIS TIME FRAME WITHOUT A BREAKDOWN IN THE FLOW PATTERN UNTIL LATE IN THE WEEKEND WHEN A TROUGH MOVES OVER THE NORTHERN U.S. THERE IS MODEL DISAGREEMENT IN THE LOCATION AND TIMING OF A WAVE AHEAD OF THE MAIN TROUGH. THUS ANY IMPACT TO THE AREA COULD ONLY BE CONSIDERED PRELIMINARY AT THIS TIME. THE RIDGE IN PLACE WILL HELP SET THE STAGE FOR TEMPERATURES CLIMBING ABOVE 90 ONCE MORE. -JUANITA && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1241 AM CDT MON JUN 17 2013 A SQUALL LINE OF THUNDERSTORMS WILL CONTINUE TO RACE EASTWARD ACROSS THE REGION TONIGHT. DAMAGING WINDS OF 60 MPH FROM THE WEST ARE EXPECTED WITH THIS LINE OF THUNDERSTORMS. CONDITIONS WILL BEGIN TO IMPROVE ONCE THE LINE OF THUNDERSTORMS MOVES THROUGH THE AREA WITH LIGHT EASTERLY WINDS DEVELOPING IN ITS WAKE. JAKUB && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 64 84 65 84 / 10 10 10 40 HUTCHINSON 63 84 65 84 / 10 10 20 40 NEWTON 63 83 64 83 / 10 10 10 40 ELDORADO 63 83 64 83 / 10 10 10 30 WINFIELD-KWLD 65 84 66 85 / 10 10 10 40 RUSSELL 61 84 64 83 / 20 10 30 50 GREAT BEND 62 84 64 84 / 20 10 30 50 SALINA 62 84 64 83 / 10 10 20 40 MCPHERSON 62 83 64 83 / 10 10 20 40 COFFEYVILLE 65 85 66 85 / 10 10 0 30 CHANUTE 63 84 65 84 / 0 0 0 30 IOLA 62 83 64 83 / 0 0 0 30 PARSONS-KPPF 64 84 65 84 / 10 0 0 30 && .ICT WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH THIS AFTERNOON FOR KSZ071-072-095-096- 098>100. FLOOD WATCH THROUGH THIS AFTERNOON FOR KSZ094. && $$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1141 PM CDT SUN JUN 16 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 326 PM CDT SUN JUN 16 2013 TRICKY FORECAST FOR THE FIRST 12-24 HOURS WITH MANY FACTORS IN PLAY FOR CONVECTION POTENTIAL...AND DIFFERENCES IN GUIDANCE AS TO HOW/WHERE/WHEN STORMS EVOLVE. CURRENTLY VERY LITTLE CIN OVER THE FORECAST AREA WITH AN AREA OF GENERALLY 1500-2000J/KG CAPE BISECTING THE FA FROM NW TO SE. BULK SHEAR HOWEVER IS QUITE LOW...LESS THAN 10KTS WITHIN THE FIRST 15KFT PER NAM SOUNDINGS. PER CU FIELD ON VISIBLE AND WINDS IN OBS WOULD APPEAR THAT BOUNDARY HAS MADE IT SOUTH OF EMPORIA...WITH SOME WEAK WIND CONVERGENCE JUST SOUTH. NOT CONFIDENT OF DEVELOPMENT ON THIS BOUNDARY BUT WILL LEAVE A SLIGHT CHANCE SOUTH AND WEST TO ACCOUNT FOR PROBABILITY. STARTING TO SEE CONVECTION DEVELOP IN SW NEBRASKA AS WELL AS FAR SW SOUTH DAKOTA AT THIS HOUR. MOISTURE AXIS AND CORFIDI VECTORS INDICATE THESE STORMS WOULD MOVE TO THE EAST TO SOUTHEAST WITH TIME...BECOMING A CLUSTER AND MOVING ACROSS WESTERN AND PORTIONS OF CENTRAL KANSAS. HOW FAR EASTWARD THEY CAN DEVELOP IS IN QUESTION...WITH THE NAM/GFS/EC TAKING THE BRUNT OF THE QPF MAINLY WEST OF OUR FORECAST AREA. LAST FEW RUNS OF THE HRRR BRING A SQUALL LINE ACROSS MUCH OF THE FORECAST AREA GENERALLY 9PM TO AFTER MIDNIGHT. THINK THE EARLIER SCENARIO IS MORE LIKELY AND WILL TAKE MOST OF THE LLJ ENERGY INTO THE WESTERNMOST STORM COMPLEX...THINKING WON`T BE ABLE TO DEVELOP A LINE OF STORMS FURTHER EAST BACK TOWARD THE COOLER AIR. ONCE AGAIN WILL GO WITH CHANCE POPS TO THE WEST AND DECREASE CHANCES EAST...BUT NOT WILLING TO TAKE POPS OUT FAR EAST JUST YET GIVEN MODEL DIFFERENCES. ENOUGH INSTABILITY WITH A LINE OF STORMS TO MAKE WIND AND HEAVY RAIN A CONCERN...BUT SHEAR PROFILES NOT AS FAVORABLE FOR LOW LEVEL ROTATION. STORMS MOVE EASTWARD QUICKLY AND HAVE A DRY FORECAST ALL AREAS BY AFTERNOON. HAVE LOWS IN THE 60S TONIGHT WITH HIGHS IN THE 80S ON MONDAY...COOLER SE WHERE CLOUDS AND RAIN MAY LINGER A FEW HOURS INTO THE MORNING MONDAY. 67 .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 326 PM CDT SUN JUN 16 2013 MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SUNDAY)... EXPECT LARGE SCALE RIDGING TO TAKE PLACE IN THE MID RANGE TO EXTENDED PERIOD OF THE FORECAST...WHICH WILL LIKELY SPELL A CONSISTENT PERIOD OF ABOVE NORMAL TEMPERATURES THROUGH THE END OF THE WORK WEEK AND THROUGH NEXT THE WEEKEND. HIGHS WILL LIKELY REACH THE MID TO UPPER 90S...HOWEVER AS THAT TIME PERIOD APPROACHES AND MODELS CONTINUE CONSISTENCY IN BRINGING IN THE MID LEVEL RIDGE PERHAPS WE COULD SEE TEMPERATURES LATE IN THE WEEK AND THIS WEEKEND REACH THE TRIPLE DIGIT MARK...ESPECIALLY IN THE WESTERN ZONES WHERE MOISTURE COULD BE A LITTLE HARDER TO COME BY. PRECIP CHANCES THROUGH THE EXTENDED WILL BE TOUGH TO NAIL DOWN...AS THERE ARE NO REAL STRONG MID LEVEL SIGNALS TO REALLY TRACK FOR PRECIP. THE BEST CHANCE FOR PRECIP DOES LOOK LIKE IT WILL TAKE PLACE IN THE MID TO LATE PART OF THE WEEK AS MODELS HINT AT SOME STRONG CONVECTION TAKING PLACE OFF THE HIGH PLAINS...AND DRAGGING THE CONVECTION EASTWARD THROUGH THE CENTRAL PLAINS. THE POSITION OF THE MID LEVEL TROUGH AND THE SUBSEQUENT STEERING FLOW WILL LIKELY DETERMINE THE EXACT TRACK OF THE PRECIP. SHOULD THE RIDGE BECOME LESS AMPLIFIED THE W-SW STEERING FLOW MAY END UP OVER THE FORECAST AREA...HOWEVER SHOULD THE RIDGE BE A LITTLE STRONGER THAN ANTICIPATED IT WOULD SHUNT THE CONVECTION NORTH. EITHER WAY...WILL MAINTAIN CHANCE POPS FOR THE WED NIGHT THROUGH FRIDAY TIME FRAME FOR THESE SHOWERS. OTHERWISE...THE MAINLY DRY AND WARM FORECAST DESCRIBED ABOVE WILL BE EXPECTED THROUGH THE EXTENDED. JL && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1141 PM CDT SUN JUN 16 2013 FOR THE 06Z TAFS...TWO AREAS OF SHOWERS AND THUNDERSTORMS CONTINUED TO DEVELOP ACROSS CENTRAL KANSAS...TRACKING SOUTH AND EAST INTO SOUTHEASTERN KANSAS. AS THESE TWO AREAS MERGE TOGETHER...MAY SEE MORE SCATTERED ACTIVITY OVER CENTRAL AND EAST CENTRAL KANSAS THROUGH MONDAY MORNING. THERE IS SOME UNCERTAINTY REGARDING HOW LONG THIS ACTIVITY WILL PERSIST INTO THE MORNING HOURS. DRY CONDITIONS EXPECTED DURING THE AFTERNOON AND EVENING HOURS WITH LIGHT NORTHEASTERLY WINDS. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...67 LONG TERM...LEIGHTON AVIATION...HENNECKE
AREA FORECAST DISCUSSION
NWS PADUCAH KY
253 PM CDT MON JUN 17 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 242 PM CDT MON JUN 17 2013 MID LVL SHORT WAVE DRIFTING SLOWLY EWD THROUGH MO WILL CONTINUE TO SPAWN SCAT TO NUMEROUS SHOWER/THUNDERSTORM ACTIVITY THIS EVENING AND OVERNIGHT AS A SURFACE WAVE FORMS OVER AR AND DRIFTS EAST INTO TN. THIS SHORT WAVE AND SFC FEATURE WILL BE QUITE SLOW TO MOVE THIS EVENING INTO THE OVERNIGHT HOURS. THUS...LOCALLY HEAVY RAINFALL REMAINS A POSSIBILITY. THUNDERSTORM CLUSTERS MAY ACTUALLY PROPAGATE FROM SE TO NW OVER THE SAME LOCATIONS AT TIMES. AS THE NIGHT PROGRESSES...THE GREATEST HEAVY RAIN THREAT SHOULD SHRINK TO OUR S/SE AREAS...CLOSEST TO THE SFC BOUNDARY. ANOTHER MID LVL SHORT WAVE WILL MOVE SE TOWARD THE REGION ON TUESDAY. HOWEVER...THIS WAVE SHOULD BE MUCH MORE MOISTURE STARVED WITH LITTLE OR NO LOW LEVEL FORCING /SFC BOUNDARY/. THUS...NOT EXPECTING NEAR THE COVERAGE OR INTENSITY OF PRECIPITATION ON TUESDAY THAT HAS BEEN EXPERIENCED TODAY. HIGH PRESSURE AND DRIER CONDITIONS WILL BECOME MUCH MORE ESTABLISHED BY THE MID WEEK TIME FRAME AND TEMPS SHOULD REMAIN CLOSE TO SEASONAL NORMS. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 242 PM CDT MON JUN 17 2013 CONFIDENCE CONTINUES TO INCREASE ON A GENERALLY RAINFREE...YET WARMING TIME PERIOD. MID LVL RIDGING OVER THE SOUTHERN AND CENTRAL PLAINS DURING THE LATTER PART OF THE WORK WEEK WILL EVENTUALLY MIGRATE EASTWARD INTO THE MISSISSIPPI RIVER VALLEY BY SAT. THIS WILL MOST LIKELY LEAD TO A RAINFREE PERIOD RIGHT THROUGH THE WEEKEND. HOWEVER...AS THE RIDGE SHIFTS CLOSER TO US...ESPECIALLY NEXT WEEKEND...WE WILL UNDERGO A NOTICEABLE RETURN TO HEAT AND HUMIDITY. EXPECT HIGH TEMPS INTO THE LOWER 90S NEXT WEEKEND...WITH HEAT INDICES LIKELY TOPPING OUT NEAR THE CENTURY MARK BOTH DAYS. && .AVIATION... ISSUED AT 1230 PM CDT MON JUN 17 2013 VFR CIGS/VSBYS THROUGH MOST OF THE 18Z TAF PERIOD. HRRR MESOSCALE MODEL HAS HAD A GOOD OVERALL HANDLE ON CONVECTIVE TRENDS THIS MORNING...SO HAVE CHOSEN TO FOLLOW THAT SOLUTION INTO THE AFTERNOON AND EARLY EVENING. BEST CHC FOR TSTMS WILL BE OVER KCGI/KPAH THIS AFTERNOON...POSSIBLY AFFECTING KEVV 21Z-02Z FRAME. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...MEFFERT LONG TERM...MEFFERT AVIATION...MEFFERT
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1225 PM CDT MON JUN 17 2013 .UPDATE... ISSUED AT 1219 PM CDT MON JUN 17 2013 FOR AVIATION SECTION ONLY. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 324 AM CDT MON JUN 17 2013 SHORT TERM WEATHER SOLUTION CONTINUES TO BE RATHER UNCLEAR MAINLY DUE TO MODEL DISCREPANCIES. SYNOPTICALLY SPEAKING...AT THE SURFACE THERE IS AN E-W STATIONARY FRONTAL BOUNDARY TO THE NORTH OF OUR CWA...WE HAVE A WEST NORTHWEST FLOW ALOFT WITH MULTIPLE RIPPLES OF ENERGY UPSTREAM...AND SOUTHERLY FLOW AT THE SURFACE HAS BROUGHT DECENT LOW LEVEL MOISTURE ACROSS THE REGION. AS A RESULT...PRECIP CHANCES SHOULD INCREASE FROM THE WEST TODAY AS THE H5 ENERGY TAPS INTO THE MOISTURE AT HAND. PRECIP CHANCES SHOULD PEAK AREA WIDE THIS AFTERNOON AND EVENING AS THE MAIN SHORT WAVE PULLS THE AFOREMENTIONED FRONTAL BOUNDARY TOWARD THE REGION. MODELS APPEAR TO WASH FRONTAL BOUNDARY OUT AS IT APPROACHES...SO ITS HARD TO SAY WHEN OR IF WE WILL HAVE A FROPA. EITHER WAY...PRECIP CHANCES START TO TAPER OFF FROM THE WEST LATE TONIGHT INTO TUESDAY. HOWEVER...WITH ANOTHER SHORT WAVE FORECAST TO DIVE SOUTHEAST ACROSS THE REGION ON TUESDAY COMBINED WITH RESIDUAL MOISTURE...MODELS ARE CRANKING OUT A SMATTERING OF QPF ACROSS ALL OF THE REGION...SO DECIDED TO KEEP POPS ACROSS THE ENTIRE CWA. TUESDAY NIGHT SURFACE HIGH PRESSURE WILL BEGIN TO OVERSPREAD THE REGION. TEMPERATURES WILL REMAIN CLOSE TO NORMAL THROUGH THE SHORT TERM PERIOD. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 324 AM CDT MON JUN 17 2013 CONFIDENCE HAS INCREASED FOR THE WORK WEEK...BUT DECREASES FOR THE WEEKEND. THE RIDGING ALOFT OVER THE PLAINS HAS MIGRATED EASTWARD MORE INTO THE MID MISSISSIPPI VALLEY. THUS MITIGATING POPS FOR THE WEEK AND PUT THE WARM FRONT PASSAGE OFF UNTIL THE WEEKEND WHICH ORIGINALLY WAS PROGGED FOR THURSDAY TWO DAYS PAST. THIS IS THE REASON FOR THE INCREASE CONFIDENCE IN THE WORK WEEK AND DECREASED CERTAINTY FOR THE WEEKEND. CONSIDERING THE AFOREMENTIONED OPTED TO LEAVE THE FORECAST DRY. IN ADDITION...FORECAST SOUNDINGS CONTINUE TO INDICATE SIGNIFICANTLY DRIER AIR IN PLACE FOR THE ENTIRE RUN AS HAS BEEN THE CASE FOR THE PAST FOUR OR FIVE DAYS. THIS WOULD PROBABLY ACCOUNT FOR THE DECREASE IN COVERAGE AND INTENSITY SCHEDULED FOR TODAY WHICH FURTHER SUPPORTS THE EXTENDED STRATEGY. ONE THINGS THAT HAS REMAINED CONSTANT IS THE WARMING TREND ANTICIPATED AFTER FROPA TODAY AND WE CONTINUE TO EMBRACE THIS TREND WITH TEMPS HEADING TOWARD THE 90S AS THE WEEKEND APPROACHES. && .AVIATION... ISSUED AT 639 AM CDT MON JUN 17 2013 VFR CIGS/VSBYS THROUGH MOST OF THE 18Z TAF PERIOD. HRRR MESOSCALE MODEL HAS HAD A GOOD OVERALL HANDLE ON CONVECTIVE TRENDS THIS MORNING...SO HAVE CHOSEN TO FOLLOW THAT SOLUTION INTO THE AFTERNOON AND EARLY EVENING. BEST CHC FOR TSTMS WILL BE OVER KCGI/KPAH THIS AFTERNOON...POSSIBLY AFFECTING KEVV 21Z-02Z FRAME. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ UPDATE...GM
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1225 PM EDT MON JUN 17 2013 .SYNOPSIS... LOW PRESSURE WILL CROSS THE REGION TODAY BRINGING A COLD FRONT ACROSS THE AREA BY TONIGHT. A SECOND COLD FRONT IS EXPECTED TO CROSS THE REGION ON TUESDAY WITH COOLER AIR TUESDAY NIGHT INTO WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... 1225 PM...CONVECTION IS BEGINNING TO FIRE OFF ACROSS NRN NY STATE EAST INTO SW MAINE. THE LATEST MESOSCALE ANALYSIS INDICATES A STRONG THETA-E RIDGE ACROSS DOWNEAST MAINE WHERE THERE WAS STRONG SOLAR HEATING THIS MORNING. MUCAPE VALUES ARE AROUND 500-1000 J/KG ACROSS DOWNEAST MAINE AS OF NOON. THE THINKING REMAINS THAT CONVECTION WILL INITIATE ACROSS THE CENTRAL HIGHLANDS AND MOVE ACROSS INTERIOR DOWNEAST MAINE THIS AFTERNOON. AT THIS TIME ONLY PLANNING TO MAKE SOME MINOR TWEAKS TO THE GRIDS BASED ON THE LATEST SATELLITE....RADAR...AND OBSERVATIONS. 938 AM UPDATE...LOW PRES IN SRN QUEBEC THIS MORNING IS 125 MILES NW OF QUEBEC CITY AT 13Z WITH A WARM FRONT EXTENDING FROM THE LOW AND ACROSS CENTRAL MAINE. THE LOW WILL MOVE EAST WITH THE FRONTAL BOUNDARY TO SLOWLY LIFT NORTH TODAY AHEAD OF AN APPROACHING COLD FRONT THAT IS EXPECTED TO MOVE INTO FAR NRN AND WRN MAINE TOWARD EVENING. THE AIR MASS IN THE WARM SECTOR IS EXPECTED TO BECOME MARGINALLY UNSTABLE THIS AFTERNOON ACROSS THE CENTRAL HIGHLANDS AND INTERIOR DOWNEAST WITH SBCAPES OF 700-1200 J/KG. THERE WILL BE SOME SHORTWAVES THAT GET EJECTED IN THE FLOW AROUND A DEEP UPPER LOW JUST EAST OF JAMES BAY THAT WILL WORK ACROSS THE AREA. THERE IS EXPECTED TO BE ENOUGH SHEAR BOTH SPEED AND DIRECTIONAL TO ENHANCE THE UPDRAFT POTENTIAL AND CAUSE A FEW OF THE STORMS TO BECOME STRONG/BORDERLINE SEVERE THIS AFTERNOON. THE BIGGEST THREAT WILL LIKELY BE GUSTY WIND WITH THE POTENTIAL THAT ANY OF THE STORMS THAT REALLY GET GOING COULD HAVE SOME LARGER HAIL. THE HRRR HAD AN AREA OF SHOWERS MOVING INTO THE WESTERN MOUNTAINS THIS MORNING THAT DID NOT MATERIALIZE TO THE EXTENT THE MODEL WAS SHOWING. THE LATEST HRRR HAS THE MOST CONCENTRATED AREA OF SHOWERS AND THUNDERSTORMS MID-LATE AFTERNOON INTO THIS EVENING...MAINLY ACROSS NORTHERN MAINE AND INTERIOR DOWNEAST. MADE SOME CHANGES TO THE HOURLY TEMPS THIS MORNING AS TEMPS ARE NOT RISING MUCH IN THE NORTH WHERE THE STRATUS IS THICKER. TEMPS WERE RAISED A COUPLE OF DEGREES IN THE SOUTH WHERE THERE IS MORE SUNSHINE. THE HIGH TEMPS WERE RAISED A COUPLE OF DEGREES INTERIOR DOWNEAST AND KEPT AS IS ACROSS THE NORTH WHERE THE LOW STRATUS WILL BEGIN TO LIFT BY MIDDAY AND THERE IS STILL THE POTENTIAL THAT THE MID SHIFTS HIGHS WILL REALIZED. OTHERWISE...JUST SOME MINOR TWEAKS TO THE POP/SKY GRIDS FOR THE REMAINDER OF THE MORNING. PREVIOUS DISCUSSION... PROBLEM OF THE DAY WILL BE POTENTIAL FOR CONVECTION. 630 AM UPDATE: AREAS OF DENSE FOG SEEN ALONG THE COAST THIS MORNING PER THE BAR HARBOR METARS AND THIS IS SUPPORTED BY SOME WEBCAMS IN THAT AREA. LATEST LAPS SOUNDING SHOWED MOISTURE TRAPPED BELOW 950 MBS. PATCHY FOG THROUGHOUT THE CWA MAINLY IN THE RIVER VALLEYS. THE FOG WILL BURN OFF AFTER 8AM. LATEST RADAR SHOWED SHOWERS NOW MOVING INTO NEW BRUNSWICK W/SOME PATCHY DRIZZLE IN SOME LOCALES ACROSS NORTHERN MAINE THIS MORNING. SHOWERS MOVING INTO WESTERN MAINE MTNS THIS MORNING WILL MOVE ACROSS THE CENTRAL HIGHLANDS LATER THIS MORNING. THEREFORE, BACKED DOWN THE PRECIP CHANCES TO ACROSS THE NORTH AND CARRIED A MENTION OF SCATTERED SHOWERS THIS MORNING DOWN ACROSS THE CENTRAL HIGHLANDS. PREVIOUS DISCUSSION... THINGS ARE EXPECTED TO CHANGE BY EARLY AFTERNOON AS THE FRONTAL BOUNDARY LIFTS NORTH AND THE CWA GETS INTO A PSEUDO WARM SECTOR AHEAD OF THE APCHG COLD FRONT. THIS WILL ALLOW FOR DESTABILIZATION W/SOME SUNSHINE EXPECTED W/TEMPERATURES HITTING UPPER 60S TO LOWER 70S. LLVLS WILL WARM AHEAD OF A PRE-FRONTAL BOUNDARY AID IN LLVL INSTABILITY. ALOFT, THE AIRMASS WILL BE COLD ENOUGH W/MID LEVEL TEMPERATURES(700/500MBS) RUNNING -2C/-19C RESPECTIVELY. MDL SOUNDINGS FROM THE NAM AND GFS SUPPORT POSSIBLE TSTMS EARLY THIS AFTERNOON ACROSS THE NORTH AND WESTERN AREAS W/SB CAPES OF 600-900J/KG W/THE GFS THE MOST AGGRESSIVE. 0-6KM BULK SHEAR IS FCST TO BE AROUND 35 KTS. 700-500MB LAPSE RATES FCST TO BE 6.0-6.5 ACROSS THE NORTHERN 1/2 EARLY THIS AFTERNOON AND CLOSE TO 7.0 C/KM ACROSS THE INTERIOR DOWNEAST BY MID/LATE AFTERNOON. ENOUGH LLVL MOISTURE IN PLACE W/SOME DRYING IN THE MID LEVELS WILL ADD TO THE MIX. THEREFORE, DECIDED TO ADD THE MENTION OF SMALL HAIL AND GUSTY WINDS IN FOR TSTMS ACROSS THE AFOREMENTIONED AREAS. THE ACTION WILL SHIFT TO THE CENTRAL AND INTERIOR DOWNEAST AREAS THIS AFTERNOON AND CONTINUE INTO EARLY EVENING AS TEMPERATURES ARE FCST TO WARM WELL INTO THE 70S AND DEWPOINTS CLIMB TO AROUND 60F. SW WIND SHIFTING TO THE WEST THIS AFTERNOON WILL ERODE OUT THE STABLE MARINE LAYER ALLOWING FOR FURTHER DESTABILIZATION. DECIDED TO CARRY ENHANCED WORDING W/THE TSTMS INCLUDING THE BANGOR AND CALAIS AREAS AND KEPT THE MENTION OF THUNDER OUT OF THE COAST DUE TO A SOUTH FLOW HOLDING ON LONGER. QPF WILL BE A CHALLENGE DUE TO THE EXPECTED CONVECTION. DECIDED ON A BLEND OF THE GEM/NAM12 AND GFS AND MANUALLY ADJUSTED TO ACCOUNT TO 2 AREAS OF HEAVIER AMOUNTS(0.25") W/ONE AREA ACROSS THE NORTH AND THE 2ND AREA OVER THE DOWNEAST REGION. THINGS WILL WIND DOWN TONIGHT AS THE COLD FRONT CROSSES THE REGION AS LOW PRES MOVES ACROSS SOUTHERN CANADA. SOME PARTIAL CLEARING IS EXPECTED AND THIS WILL LEAD TO SOME FOG. ATTM, DECIDED TO STAY W/PATCHY FOG. THE DAYCREW CAN ASSESS THIS FURTHER W/THE LATER MODEL RUNS. FOLLOWED THE GEM AND NAM12 FOR TEMPERATURES/DEWPOINTS FOR TONIGHT. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... HIGH PRESSURE IS EXPECTED TO BUILD IN AT THE SURFACE AT THE BEGINNING OF THIS PERIOD. AT THE SAME TIME AN UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST AND MOVE ACROSS THE REGION WEDNESDAY...HOWEVER WITH DRY CONDITIONS WILL KEEP POPS LOW. HAVE BLENDED THE GFS...SREF...NAM AND ECMWF FOR POP AND QPF GRIDS. WILL USE A BLEND OF NAM12 AND GMOS FOR WINDS. FOR TEMPERATURE GRIDS WILL INITIALIZE WITH GMOS AND WILL RAISE MINIMUM TEMPERATURE TWO DEGREES BASED ON VERIFICATION. HAVE USED THE GEM FOR DEW POINT GRIDS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST AT THE BEGINNING OF THIS PERIOD THEN CREST OVER THE REGION THURSDAY MORNING. A COLD FRONT WILL APPROACH FROM THE NORTHWEST THURSDAY NIGHT AND CROSS THE STATE FRIDAY. A FRONTAL SYSTEM WILL REMAIN NEAR THE NORTHERN PORTION OF THE STATE LATE SATURDAY THROUGH TUESDAY. HAVE USED THE GMOS TO INITIALIZE ALL GRIDS. WILL ADJUST POP AND SKY GRIDS. HAVE ALSO ADJUSTED ALL MINIMUM TEMPERATURES HIGHER AND TO BETTER FIT THREE HOUR GMOS. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... NEAR TERM: IFR AT THE NORTHERN TERMNINALS HAS BEEN SLOW TO LIFT...BUT ALL TERMINALS SHOULD BE AT LEAST MVFR BY 18Z. SCT TSTMS ARE EXPECTED TO DEVELOP THIS AFTERNOON INTO EARLY EVENING AFFECTING THE TERMINALS...ESPECIALLY KBGR AND KBHB. STRONG AND ERRATIC WIND GUSTS AND SMALL WILL BE A CONCERN. SHORT TERM: EXPECT VFR CONDITIONS TUESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM: WAVE HEIGHTS ARE RUNNING AROUND 4 FEET AT THE EASTERN MAINE SHELF THIS MORNING AND SHOULD BUILD TO 4 TO 5 FT BY THIS EVENING AS A SOUTHERLY FETCH SETS W/A SWELL COMPONENT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF 10 KTS. SHORT TERM: FOR WINDS HAVE BLENDED THE NAM12 AND GFS40 AND WILL USE 125 PERCENT OF THE MODEL BLEND FOR GUST SPEED. FOR WAVES: EXPECT WINDS ACROSS LOCAL WATERS TO BE LIGHT THROUGH THIS PERIOD SO LONG PERIOD WAVE WILL DOMINATE. EXPECT SOUTHERLY WAVE GROUP 2-3 FEET/8 SECONDS ACCOMPANIED BY SECONDARY SOUTHEAST GROUP 1-2 FEET/10 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...CB/HEWITT SHORT TERM...MIGNONE LONG TERM...MIGNONE AVIATION...CB/HEWITT/MIGNONE MARINE...CB/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
939 AM EDT MON JUN 17 2013 .SYNOPSIS... LOW PRESSURE WILL CROSS THE REGION TODAY BRINGING A COLD FRONT ACROSS THE AREA BY TONIGHT. A SECOND COLD FRONT IS EXPECTED TO CROSS THE REGION ON TUESDAY WITH COOLER AIR TUESDAY NIGHT INTO WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... 938 AM UPDATE...LOW PRES IN SRN QUEBEC THIS MORNING IS 125 MILES NW OF QUEBEC CITY AT 13Z WITH A WARM FRONT EXTENDING FROM THE LOW AND ACROSS CENTRAL MAINE. THE LOW WILL MOVE EAST WITH THE FRONTAL BOUNDARY TO SLOWLY LIFT NORTH TODAY AHEAD OF AN APPROACHING COLD FRONT THAT IS EXPECTED TO MOVE INTO FAR NRN AND WRN MAINE TOWARD EVENING. THE AIR MASS IN THE WARM SECTOR IS EXPECTED TO BECOME MARGINALLY UNSTABLE THIS AFTERNOON ACROSS THE CENTRAL HIGHLANDS AND INTERIOR DOWNEAST WITH SBCAPES OF 700-1200 J/KG. THERE WILL BE SOME SHORTWAVES THAT GET EJECTED IN THE FLOW AROUND A DEEP UPPER LOW JUST EAST OF JAMES BAY THAT WILL WORK ACROSS THE AREA. THERE IS EXPECTED TO BE ENOUGH SHEAR BOTH SPEED AND DIRECTIONAL TO ENHANCE THE UPDRAFT POTENTIAL AND CAUSE A FEW OF THE STORMS TO BECOME STRONG/BORDERLINE SEVERE THIS AFTERNOON. THE BIGGEST THREAT WILL LIKELY BE GUSTY WIND WITH THE POTENTIAL THAT ANY OF THE STORMS THAT REALLY GET GOING COULD HAVE SOME LARGER HAIL. THE HRRR HAD AN AREA OF SHOWERS MOVING INTO THE WESTERN MOUNTAINS THIS MORNING THAT DID NOT MATERIALIZE TO THE EXTENT THE MODEL WAS SHOWING. THE LATEST HRRR HAS THE MOST CONCENTRATED AREA OF SHOWERS AND THUNDERSTORMS MID-LATE AFTERNOON INTO THIS EVENING...MAINLY ACROSS NORTHERN MAINE AND INTERIOR DOWNEAST. MADE SOME CHANGES TO THE HOURLY TEMPS THIS MORNING AS TEMPS ARE NOT RISING MUCH IN THE NORTH WHERE THE STRATUS IS THICKER. TEMPS WERE RAISED A COUPLE OF DEGREES IN THE SOUTH WHERE THERE IS MORE SUNSHINE. THE HIGH TEMPS WERE RAISED A COUPLE OF DEGREES INTERIOR DOWNEAST AND KEPT AS IS ACROSS THE NORTH WHERE THE LOW STRATUS WILL BEGIN TO LIFT BY MIDDAY AND THERE IS STILL THE POTENTIAL THAT THE MID SHIFTS HIGHS WILL REALIZED. OTHERWISE...JUST SOME MINOR TWEAKS TO THE POP/SKY GRIDS FOR THE REMAINDER OF THE MORNING. PREVIOUS DISCUSSION... PROBLEM OF THE DAY WILL BE POTENTIAL FOR CONVECTION. 630 AM UPDATE: AREAS OF DENSE FOG SEEN ALONG THE COAST THIS MORNING PER THE BAR HARBOR METARS AND THIS IS SUPPORTED BY SOME WEBCAMS IN THAT AREA. LATEST LAPS SOUNDING SHOWED MOISTURE TRAPPED BELOW 950 MBS. PATCHY FOG THROUGHOUT THE CWA MAINLY IN THE RIVER VALLEYS. THE FOG WILL BURN OFF AFTER 8AM. LATEST RADAR SHOWED SHOWERS NOW MOVING INTO NEW BRUNSWICK W/SOME PATCHY DRIZZLE IN SOME LOCALES ACROSS NORTHERN MAINE THIS MORNING. SHOWERS MOVING INTO WESTERN MAINE MTNS THIS MORNING WILL MOVE ACROSS THE CENTRAL HIGHLANDS LATER THIS MORNING. THEREFORE, BACKED DOWN THE PRECIP CHANCES TO ACROSS THE NORTH AND CARRIED A MENTION OF SCATTERED SHOWERS THIS MORNING DOWN ACROSS THE CENTRAL HIGHLANDS. PREVIOUS DISCUSSION... THINGS ARE EXPECTED TO CHANGE BY EARLY AFTERNOON AS THE FRONTAL BOUNDARY LIFTS NORTH AND THE CWA GETS INTO A PSEUDO WARM SECTOR AHEAD OF THE APCHG COLD FRONT. THIS WILL ALLOW FOR DESTABILIZATION W/SOME SUNSHINE EXPECTED W/TEMPERATURES HITTING UPPER 60S TO LOWER 70S. LLVLS WILL WARM AHEAD OF A PRE-FRONTAL BOUNDARY AID IN LLVL INSTABILITY. ALOFT, THE AIRMASS WILL BE COLD ENOUGH W/MID LEVEL TEMPERATURES(700/500MBS) RUNNING -2C/-19C RESPECTIVELY. MDL SOUNDINGS FROM THE NAM AND GFS SUPPORT POSSIBLE TSTMS EARLY THIS AFTERNOON ACROSS THE NORTH AND WESTERN AREAS W/SB CAPES OF 600-900J/KG W/THE GFS THE MOST AGGRESSIVE. 0-6KM BULK SHEAR IS FCST TO BE AROUND 35 KTS. 700-500MB LAPSE RATES FCST TO BE 6.0-6.5 ACROSS THE NORTHERN 1/2 EARLY THIS AFTERNOON AND CLOSE TO 7.0 C/KM ACROSS THE INTERIOR DOWNEAST BY MID/LATE AFTERNOON. ENOUGH LLVL MOISTURE IN PLACE W/SOME DRYING IN THE MID LEVELS WILL ADD TO THE MIX. THEREFORE, DECIDED TO ADD THE MENTION OF SMALL HAIL AND GUSTY WINDS IN FOR TSTMS ACROSS THE AFOREMENTIONED AREAS. THE ACTION WILL SHIFT TO THE CENTRAL AND INTERIOR DOWNEAST AREAS THIS AFTERNOON AND CONTINUE INTO EARLY EVENING AS TEMPERATURES ARE FCST TO WARM WELL INTO THE 70S AND DEWPOINTS CLIMB TO AROUND 60F. SW WIND SHIFTING TO THE WEST THIS AFTERNOON WILL ERODE OUT THE STABLE MARINE LAYER ALLOWING FOR FURTHER DESTABILIZATION. DECIDED TO CARRY ENHANCED WORDING W/THE TSTMS INCLUDING THE BANGOR AND CALAIS AREAS AND KEPT THE MENTION OF THUNDER OUT OF THE COAST DUE TO A SOUTH FLOW HOLDING ON LONGER. QPF WILL BE A CHALLENGE DUE TO THE EXPECTED CONVECTION. DECIDED ON A BLEND OF THE GEM/NAM12 AND GFS AND MANUALLY ADJUSTED TO ACCOUNT TO 2 AREAS OF HEAVIER AMOUNTS(0.25") W/ONE AREA ACROSS THE NORTH AND THE 2ND AREA OVER THE DOWNEAST REGION. THINGS WILL WIND DOWN TONIGHT AS THE COLD FRONT CROSSES THE REGION AS LOW PRES MOVES ACROSS SOUTHERN CANADA. SOME PARTIAL CLEARING IS EXPECTED AND THIS WILL LEAD TO SOME FOG. ATTM, DECIDED TO STAY W/PATCHY FOG. THE DAYCREW CAN ASSESS THIS FURTHER W/THE LATER MODEL RUNS. FOLLOWED THE GEM AND NAM12 FOR TEMPERATURES/DEWPOINTS FOR TONIGHT. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... HIGH PRESSURE IS EXPECTED TO BUILD IN AT THE SURFACE AT THE BEGINNING OF THIS PERIOD. AT THE SAME TIME AN UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST AND MOVE ACROSS THE REGION WEDNESDAY...HOWEVER WITH DRY CONDITIONS WILL KEEP POPS LOW. HAVE BLENDED THE GFS...SREF...NAM AND ECMWF FOR POP AND QPF GRIDS. WILL USE A BLEND OF NAM12 AND GMOS FOR WINDS. FOR TEMPERATURE GRIDS WILL INITIALIZE WITH GMOS AND WILL RAISE MINIMUM TEMPERATURE TWO DEGREES BASED ON VERIFICATION. HAVE USED THE GEM FOR DEW POINT GRIDS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST AT THE BEGINNING OF THIS PERIOD THEN CREST OVER THE REGION THURSDAY MORNING. A COLD FRONT WILL APPROACH FROM THE NORTHWEST THURSDAY NIGHT AND CROSS THE STATE FRIDAY. A FRONTAL SYSTEM WILL REMAIN NEAR THE NORTHERN PORTION OF THE STATE LATE SATURDAY THROUGH TUESDAY. HAVE USED THE GMOS TO INITIALIZE ALL GRIDS. WILL ADJUST POP AND SKY GRIDS. HAVE ALSO ADJUSTED ALL MINIMUM TEMPERATURES HIGHER AND TO BETTER FIT THREE HOUR GMOS. && .AVIATION /13Z MONDAY THROUGH FRIDAY/... NEAR TERM: IFR AT THE NORTHERN TERMNINALS WILL IMPRVE TO VFR BY LATE MORNING TO MIDDAY WITH VFR AT KBGR AND KBHB. TSTMS ARE POSSIBLE THIS AFTERNOON INTO EARLY EVENING AFFECTING THE TERMINALS. STRONG AND ERRATIC WIND GUSTS AND SMALL WILL BE A CONCERN. SHORT TERM: EXPECT VFR CONDITIONS TUESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM: WAVE HEIGHTS ARE RUNNING AROUND 3 FEET AT THE EASTERN MAINE SHELF THIS MORNING AND SHOULD BUILD TO 4 TO 5 FT BY THIS EVENING AS A SOUTHERLY FETCH SETS W/A SWELL COMPONENT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF 10 KTS. SHORT TERM: FOR WINDS HAVE BLENDED THE NAM12 AND GFS40 AND WILL USE 125 PERCENT OF THE MODEL BLEND FOR GUST SPEED. FOR WAVES: EXPECT WINDS ACROSS LOCAL WATERS TO BE LIGHT THROUGH THIS PERIOD SO LONG PERIOD WAVE WILL DOMINATE. EXPECT SOUTHERLY WAVE GROUP 2-3 FEET/8 SECONDS ACCOMPANIED BY SECONDARY SOUTHEAST GROUP 1-2 FEET/10 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...CB/HEWITT SHORT TERM...MIGNONE LONG TERM...MIGNONE AVIATION...CB/HEWITT/MIGNONE MARINE...CB/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
323 AM EDT MON JUN 17 2013 .SYNOPSIS... LOW PRESSURE WILL CROSS THE REGION TODAY BRINGING A COLD FRONT ACROSS THE AREA BY TONIGHT. A SECOND COLD FRONT IS EXPECTED TO CROSS THE REGION ON TUESDAY WITH COOLER AIR TUESDAY NIGHT INTO WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... PROBLEM OF THE DAY WILL BE POTENTIAL FOR CONVECTION. THE ATMOSPHERE IS STABLE W/STRATUS AND RAIN MOVING ACROSS THE REGION EARLY THIS MORNING. STEADY RAINFALL HAS SHIFTED TO NERN MAINE AND WESTERN NEW BRUNSWICK AS DEPICTED BY THE LATEST RADAR MOSAIC. 00Z UA SHOWED A NICE JETLET AT 700MBS ENHANCING THE RAINFALL. A FRONTAL BOUNDARY REMAINS IN PLACE ACROSS NORTH CENTRAL MAINE W/AN AREA OF LOW PRES MOVING THROUGH NORTHERN AREAS AS OF 06Z. TEMPERATURES WERE HOLDING IN THE MID TO UPPER 50S ACROSS CENTRAL AND DOWNEAST AREAS(SOUTH OF THE FRONT) AND IN THE UPPER 40S AND LOWER 50S ACROSS NORTHERN MAINE IN IN CLOSE PROXIMITY OF THE FRONT. THE REGIONAL GEM AND RUC WERE HANDLING THIS LATEST SITUATION THE BEST AND THIS HOW THE FORECAST WAS RUN THROUGH THIS MORNING W/CLOUDS, WIDELY SCATTERED SHOWERS AND SOME FOG. THINGS ARE EXPECTED TO CHANGE BY EARLY AFTERNOON AS THE FRONTAL BOUNDARY LIFTS NORTH AND THE CWA GETS INTO A PSEUDO WARM SECTOR AHEAD OF THE APCHG COLD FRONT. THIS WILL ALLOW FOR DESTABILIZATION W/SOME SUNSHINE EXPECTED W/TEMPERATURES HITTING UPPER 60S TO LOWER 70S. LLVLS WILL WARM AHEAD OF A PRE-FRONTAL BOUNDARY AID IN LLVL INSTABILITY. ALOFT, THE AIRMASS WILL BE COLD ENOUGH W/MID LEVEL TEMPERATURES(700/500MBS) RUNNING -2C/-19C RESPECTIVELY. MDL SOUNDINGS FROM THE NAM AND GFS SUPPORT POSSIBLE TSTMS EARLY THIS AFTERNOON ACROSS THE NORTH AND WESTERN AREAS W/SB CAPES OF 600-900J/KG W/THE GFS THE MOST AGGRESSIVE. 0-6KM BULK SHEAR IS FCST TO BE AROUND 35 KTS. 700-500MB LAPSE RATES FCST TO BE 6.0-6.5 ACROSS THE NORTHERN 1/2 EARLY THIS AFTERNOON AND CLOSE TO 7.0 C/KM ACROSS THE INTERIOR DOWNEAST BY MID/LATE AFTERNOON. ENOUGH LLVL MOISTURE IN PLACE W/SOME DRYING IN THE MID LEVELS WILL ADD TO THE MIX. THEREFORE, DECIDED TO ADD THE MENTION OF SMALL HAIL AND GUSTY WINDS IN FOR TSTMS ACROSS THE AFOREMENTIONED AREAS. THE ACTION WILL SHIFT TO THE CENTRAL AND INTERIOR DOWNEAST AREAS THIS AFTERNOON AND CONTINUE INTO EARLY EVENING AS TEMPERATURES ARE FCST TO WARM WELL INTO THE 70S AND DEWPOINTS CLIMB TO AROUND 60F. SW WIND SHIFTING TO THE WEST THIS AFTERNOON WILL ERODE OUT THE STABLE MARINE LAYER ALLOWING FOR FURTHER DESTABILIZATION. DECIDED TO CARRY ENHANCED WORDING W/THE TSTMS INCLUDING THE BANGOR AND CALAIS AREAS AND KEPT THE MENTION OF THUNDER OUT OF THE COAST DUE TO A SOUTH FLOW HOLDING ON LONGER. QPF WILL BE A CHALLENGE DUE TO THE EXPECTED CONVECTION. DECIDED ON A BLEND OF THE GEM/NAM12 AND GFS AND MANUALLY ADJUSTED TO ACCOUNT TO 2 AREAS OF HEAVIER AMOUNTS(0.25") W/ONE AREA ACROSS THE NORTH AND THE 2ND AREA OVER THE DOWNEAST REGION. THINGS WILL WIND DOWN TONIGHT AS THE COLD FRONT CROSSES THE REGION AS LOW PRES MOVES ACROSS SOUTHERN CANADA. SOME PARTIAL CLEARING IS EXPECTED AND THIS WILL LEAD TO SOME FOG. ATTM, DECIDED TO STAY W/PATCHY FOG. THE DAYCREW CAN ASSESS THIS FURTHER W/THE LATER MODEL RUNS. FOLLOWED THE GEM AND NAM12 FOR TEMPERATURES/DEWPOINTS FOR TONIGHT. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... HIGH PRESSURE IS EXPECTED TO BUILD IN AT THE SURFACE AT THE BEGINNING OF THIS PERIOD. AT THE SAME TIME AN UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST AND MOVE ACROSS THE REGION WEDNESDAY...HOWEVER WITH DRY CONDITIONS WILL KEEP POPS LOW. HAVE BLENDED THE GFS...SREF...NAM AND ECMWF FOR POP AND QPF GRIDS. WILL USE A BLEND OF NAM12 AND GMOS FOR WINDS. FOR TEMPERATURE GRIDS WILL INITIALIZE WITH GMOS AND WILL RAISE MINIMUM TEMPERATURE TWO DEGREES BASED ON VERIFICATION. HAVE USED THE GEM FOR DEW POINT GRIDS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST AT THE BEGINNING OF THIS PERIOD THEN CREST OVER THE REGION THURSDAY MORNING. A COLD FRONT WILL APPROACH FROM THE NORTHWEST THURSDAY NIGHT AND CROSS THE STATE FRIDAY. A FRONTAL SYSTEM WILL REMAIN NEAR THE NORTHERN PORTION OF THE STATE LATE SATURDAY THROUGH TUESDAY. HAVE USED THE GMOS TO INITIALIZE ALL GRIDS. WILL ADJUST POP AND SKY GRIDS. HAVE ALSO ADJUSTED ALL MINIMUM TEMPERATURES HIGHER AND TO BETTER FIT THREE HOUR GMOS. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... NEAR TERM: IFR/MVFR ACROSS THE REGION THIS MORNING. CONDITIONS WILL IMPROVE TO VFR BY MID TO LATE MORNING. TSTMS ARE POSSIBLE THIS AFTERNOON INTO EARLY EVENING AFFECTING THE TERMINALS. WIND SHEAR AND SMALL WILL BE A CONCERN. DAYCREW WILL NEED TO MONITOR FOR POSSIBLE AWW FOR BIA THIS AFTERNOON IF TSTMS FIRE. SHORT TERM: EXPECT VFR CONDITIONS TUESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM: NO HEADLINES FOR THIS TERM. WAVE HEIGHTS WERE ADJUSTED TO BRING THEM UP A FOOT W/A FCST OF 5 FT BY THIS EVENING AS A SOUTHERLY FETCH SETS W/A SWELL COMPONENT. WINDS WILL BE LIGHT AVERAGING SPEEDS OF 10 KTS. DECIDED ON THE NAM12/GFS40 AND GEM FOR THE SUSTAINED WINDS. SHORT TERM: FOR WINDS HAVE BLENDED THE NAM12 AND GFS40 AND WILL USE 125 PERCENT OF THE MODEL BLEND FOR GUST SPEED. FOR WAVES: EXPECT WINDS ACROSS LOCAL WATERS TO BE LIGHT THROUGH THIS PERIOD SO LONG PERIOD WAVE WILL DOMINATE. EXPECT SOUTHERLY WAVE GROUP 2-3 FEET/8 SECONDS ACCOMPANIED BY SECONDARY SOUTHEAST GROUP 1-2 FEET/10 SECONDS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT SHORT TERM...MIGNONE LONG TERM...MIGNONE AVIATION...HEWITT/MIGNONE MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
515 PM EDT MON JUN 17 2013 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN IN THE VICINITY OF THE UPPER OHIO VALLEY...MAINTAINING CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH THE DAY ON TUESDAY. HIGH PRESSURE WILL MOVE INTO THE REGION FROM THE NORTHWEST ON WEDNESDAY...PROMOTING GENERALLY DRY AND SEASONABLE WEATHER THROUGH THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... FCST UPDATED TO REFLECT ONGOING SVR TSTMS IN ERN OH. HIGHER MSTR CONTENT HAS PROMOTED STRONGER INSTBY SUCH THAT A FEW TSTMS WERE ABLE TO STRENGTHEN THRU THE MID-LVL WARM AIR. HAIL AND WIND HAVE BEEN REPORTED. POPS AND QPF WERE INCRD. OTHERWISE...NO CHGS ATTM. PREV DISCUSSION FOLLOWS. AN ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO INCREASE POPS TO ACCOUNT FOR DEVELOPING UPSTREAM SHOWERS AND THUNDERSTORMS. THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A WEAK AND BROAD CYCLONIC FLOW ACROSS THE UPPER OHIO VALLEY WITH DRIER AND SLIGHTLY WARMER AIR ADVECTING IN FROM THE WEST. 850MB CONVERGENCE ALONG THE MASON-DIXON LINE HAS WEAKENED MOSTLY WITH ONLY AN ISOLATED SHOWER OR TWO REMAINING ACROSS THE ALLEGHENY FRONT. THE CONVERGENCE ZONE HAS BEEN CO-LOCATED WITH A FRONTAL BOUNDARY NEAR THE MASON-DIXON LINE. ALTHOUGH A THERMAL GRADIENT IS LACKING ALONG THE BOUNDARY...IT CAN BE MORE EASILY DEPICTED BY SURFACE DEW POINT AND EQUIVALENT POTENTIAL TEMPERATURE GRADIENTS. UPSTREAM...SOME LAKE BREEZE INTERACTION (LAKE ERIE) WITH A SOUTHWESTERLY LOW-LEVEL FLOW HAS SETUP A CONVERGENCE ZONE OF CONVECTION ACROSS NORTHERN OHIO. THIS EVENING...THE FRONTAL BOUNDARY WILL REMAIN FAIRLY STATIONARY IN THE VICINITY OF THE MASON-DIXON LINE. THERE ARE A FEW CONTRIBUTORS HAT HAVE LED TO THE FORECAST FOR POSSIBLE CONVECTION INTO THE EVENING. THESE INCLUDE...THE FRONTAL BOUNDARY AND INSTABILITY INCREASING TO 1500-2500 J/KG SBCAPE FOR LOCATIONS PRIMARILY SOUTH OF PITTSBURGH. FOR LOCATIONS NORTH AND WEST OF PITTSBURGH...CHC OF THUNDERSTORMS IS FORECAST WITH ONGOING DEVELOPING CONVECTION IN NORTHERN OHIO. WITH THIS AND THE 14Z HRRR IN MIND HAVE GONE WITH SCHC INCREASING TO CHC POP THROUGH MUCH THE EVENING. TONIGHT...LINGERING CONVECTION WILL BE ONGOING FROM DIURNAL ACTIVITY RELATED TO THE SERIES OF BOUNDARIES LOCATED IN THE VICINITY OF THE FORECAST AREA. WITH THE LOSS OF HEATING...CONVECTION WILL BEGIN TO DIMINISH ACROSS THE AREA. HOWEVER...NORTHERN BOUNDARY WILL THEN BEGIN TO DROP SOUTHWARD AS A FRONT. THUS...THE FORCING PROVIDED FROM THIS FEATURE WILL ALLOW FOR THE CHC OF SHOWERS AND THUNDERSTORMS TO CONTINUE ACROSS MUCH OF THE AREA NOCTURNALLY. OVERNIGHT LOWS ARE CLOSER TO THE WARMER MET...WITH LOWS RANGING FROM THE MID 60S IN EASTERN OHIO...SW PA...AND NORTHERN WV TO THE UPPER 50S ACROSS THE ALLEGHENY FRONT AND LAUREL HIGHLANDS. TUESDAY...THE COLD FRONT WILL CONTINUE TO DROP SLOWLY SOUTHWARD ACROSS THE AREA...WITH THE COVERAGE OF SHOWER AND THUNDERSTORMS INCREASING AS A FUNCTION OF DIURNAL HEATING DURING THE DAY. INSTABILITY/SHEAR PROFILES STILL APPEAR TO NOT SUPPORT MORE ORGANIZED CONVECTION AND THUS THE CHANCE OF A STRONG TO SEVERE STORM SEEMS LIMITED AT THIS TIME. TEMP FORECAST CONTINUES TO LEAN TOWARD THE WARMER MET GUIDANCE WITH NAM 850MB TEMPS AROUND 14-15C LEADING TO FORECAST HIGH NEAR 80 ACROSS MUCH OF THE AREA. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... CDFNT WILL CONT TO SAG SEWD TUE EVE AND WILL BE ACCOMPANIED BY LINGERING SHWRS AND TSTMS. NAM IS MORE AMPLIFIED WITH ASSOCIATED H5 SHRTWV TROF AND MAINTAINS PCPN THRU WED MRNG IN THE MTNS...BUT GFS IS MORE PROGRESSIVE WITH THE SYSTEM...ENDING PCPN BY LATE TUE NGT. LOW POPS WERE RETAINED THRU WED MRNG TO REFLECT THIS UNCERTAINTY. AMID BUILDING SFC HIPRES...POST-FRONTAL AMS WILL DRY SOMEWHAT. AS A RESULT...INSTBY WILL BE LMTD TO HIGHER TERRAIN WED-THU. THUS... POPS WERE INCLUDED ONLY IN ZONES WITH HIGHER TERRAIN. ANY CNVCTN WILL BE DIURNALLY DRIVEN. POST-FRONTAL MAXIMA WILL BE ON THE COOLER SIDE IN THE MID-UPR 70S. MINIMA WILL BE DICTATED BY DEG OF DRYING OF LOW-LVL AMS...LKLY IN THE 50S. UPDATE...KRAMAR && .LONG TERM /FRIDAY THROUGH MONDAY/... MDLS CONT TO DEPICT DVLPMNT OF A BROAD SRN CONUS RIDGE FOR THE LONG TERM PD WITH GENL RIDGE AXIS POSITIONING ACRS THE GREAT LAKES. WARMER TEMPS ARE THUS IN STORE FOR THE UPR OH VALLEY REGION WITH WEEKEND READINGS PROGGED WELL INTO THE 80S AS PER HIGHER MOS GUIDANCE. GRADUALLY INCRSG POPS...TO CHC NMBRS FOR THE WEEKEND...WERE ALSO INCLUDED...BUT TIMING WL BE DEPENDENT ON SHRTWV PASSAGE ACRS THE NRN PERIPHERY OF THE RIDGE...SO CONFIDENCE IN THAT PARAMETER IS MINIMAL AT THIS JUNCTURE OF THE FORECAST PROCESS. && .AVIATION /21Z MONDAY THROUGH SATURDAY/... VFR CONDITIONS WILL MOSTLY PREVAIL THROUGH THIS EVENING...ALTHOUGH BRIEF RESTRICTIONS WILL BE POSSIBLE IN ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH THE CHANCE INCREASING TONIGHT. COVERAGE WILL BE SPARSE...ALTHOUGH IF A SHOWER/STORM HITS A TERMINAL VISIBILITY RESTRICTIONS COULD BRIEFLY DROP TO IFR. WINDS WILL BE SOUTHWESTERLY THIS AFTERNOON AT 5-10KTS. WITH A FRONT DROPPING SOUTHWARD TONIGHT...THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE...ALTHOUGH CONFIDENCE IN LOCATION AND AREAL COVERAGE IS TOO LOW TO INCLUDE IN THE TERMINALS AT THIS POINT. A BRIEF PERIOD OF RESTRICTIONS WITH FOG WILL BE POSSIBLE DURING THE PRE-DAWN HOURS ON TUESDAY. IFR CONDITIONS ARE FORECAST ALONG AND SOUTH OF THE BOUNDARY AT KMGW/KZZV WITH MVFR ELSEWHERE. A FRONTAL BOUNDARY WILL PUSH ACROSS THE AREA ON TUESDAY...WITH A BETTER CHANCE OF BRIEF IFR RESTRICTIONS WITH SHOWERS AND THUNDERSTORMS ACROSS THE TERMINALS DURING THE DAY. OUTLOOK.../TUESDAY NIGHT THROUGH FRIDAY/... THE FRONTAL BOUNDARY WILL PUSH SOUTHEAST OF THE AREA TUESDAY NIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO AN END. HIGH PRESSURE WILL THEN BUILD IN FROM THE NORTHWEST...ALLOWING FOR VFR CONDITIONS TO PREVAIL FOR THE MAJORITY ON WEDNESDAY THROUGH FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
315 PM EDT MON JUN 17 2013 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN IN THE VICINITY OF THE UPPER OHIO VALLEY...MAINTAINING CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH THE DAY ON TUESDAY. HIGH PRESSURE WILL MOVE INTO THE REGION FROM THE NORTHWEST ON WEDNESDAY...PROMOTING GENERALLY DRY AND SEASONABLE WEATHER THROUGH THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... AN ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO INCREASE POPS TO ACCOUNT FOR DEVELOPING UPSTREAM SHOWERS AND THUNDERSTORMS. THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A WEAK AND BROAD CYCLONIC FLOW ACROSS THE UPPER OHIO VALLEY WITH DRIER AND SLIGHTLY WARMER AIR ADVECTING IN FROM THE WEST. 850MB CONVERGENCE ALONG THE MASON-DIXON LINE HAS WEAKENED MOSTLY WITH ONLY AN ISOLATED SHOWER OR TWO REMAINING ACROSS THE ALLEGHENY FRONT. THE CONVERGENCE ZONE HAS BEEN CO-LOCATED WITH A FRONTAL BOUNDARY NEAR THE MASON-DIXON LINE. ALTHOUGH A THERMAL GRADIENT IS LACKING ALONG THE BOUNDARY...IT CAN BE MORE EASILY DEPICTED BY SURFACE DEW POINT AND EQUIVALENT POTENTIAL TEMPERATURE GRADIENTS. UPSTREAM...SOME LAKE BREEZE INTERACTION (LAKE ERIE) WITH A SOUTHWESTERLY LOW-LEVEL FLOW HAS SETUP A CONVERGENCE ZONE OF CONVECTION ACROSS NORTHERN OHIO. THIS EVENING...THE FRONTAL BOUNDARY WILL REMAIN FAIRLY STATIONARY IN THE VICINITY OF THE MASON-DIXON LINE. THERE ARE A FEW CONTRIBUTORS HAT HAVE LED TO THE FORECAST FOR POSSIBLE CONVECTION INTO THE EVENING. THESE INCLUDE...THE FRONTAL BOUNDARY AND INSTABILITY INCREASING TO 1500-2500 J/KG SBCAPE FOR LOCATIONS PRIMARILY SOUTH OF PITTSBURGH. FOR LOCATIONS NORTH AND WEST OF PITTSBURGH...CHC OF THUNDERSTORMS IS FORECAST WITH ONGOING DEVELOPING CONVECTION IN NORTHERN OHIO. WITH THIS AND THE 14Z HRRR IN MIND HAVE GONE WITH SCHC INCREASING TO CHC POP THROUGH MUCH THE EVENING. TONIGHT...LINGERING CONVECTION WILL BE ONGOING FROM DIURNAL ACTIVITY RELATED TO THE SERIES OF BOUNDARIES LOCATED IN THE VICINITY OF THE FORECAST AREA. WITH THE LOSS OF HEATING...CONVECTION WILL BEGIN TO DIMINISH ACROSS THE AREA. HOWEVER...NORTHERN BOUNDARY WILL THEN BEGIN TO DROP SOUTHWARD AS A FRONT. THUS...THE FORCING PROVIDED FROM THIS FEATURE WILL ALLOW FOR THE CHC OF SHOWERS AND THUNDERSTORMS TO CONTINUE ACROSS MUCH OF THE AREA NOCTURNALLY. OVERNIGHT LOWS ARE CLOSER TO THE WARMER MET...WITH LOWS RANGING FROM THE MID 60S IN EASTERN OHIO...SW PA...AND NORTHERN WV TO THE UPPER 50S ACROSS THE ALLEGHENY FRONT AND LAUREL HIGHLANDS. TUESDAY...THE COLD FRONT WILL CONTINUE TO DROP SLOWLY SOUTHWARD ACROSS THE AREA...WITH THE COVERAGE OF SHOWER AND THUNDERSTORMS INCREASING AS A FUNCTION OF DIURNAL HEATING DURING THE DAY. INSTABILITY/SHEAR PROFILES STILL APPEAR TO NOT SUPPORT MORE ORGANIZED CONVECTION AND THUS THE CHANCE OF A STRONG TO SEVERE STORM SEEMS LIMITED AT THIS TIME. TEMP FORECAST CONTINUES TO LEAN TOWARD THE WARMER MET GUIDANCE WITH NAM 850MB TEMPS AROUND 14-15C LEADING TO FORECAST HIGH NEAR 80 ACROSS MUCH OF THE AREA. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... CDFNT WILL CONT TO SAG SEWD TUE EVE AND WILL BE ACCOMPANIED BY LINGERING SHWRS AND TSTMS. NAM IS MORE AMPLIFIED WITH ASSOCIATED H5 SHRTWV TROF AND MAINTAINS PCPN THRU WED MRNG IN THE MTNS...BUT GFS IS MORE PROGRESSIVE WITH THE SYSTEM...ENDING PCPN BY LATE TUE NGT. LOW POPS WERE RETAINED THRU WED MRNG TO REFLECT THIS UNCERTAINTY. AMID BUILDING SFC HIPRES...POST-FRONTAL AMS WILL DRY SOMEWHAT. AS A RESULT...INSTBY WILL BE LMTD TO HIGHER TERRAIN WED-THU. THUS... POPS WERE INCLUDED ONLY IN ZONES WITH HIGHER TERRAIN. ANY CNVCTN WILL BE DIURNALLY DRIVEN. POST-FRONTAL MAXIMA WILL BE ON THE COOLER SIDE IN THE MID-UPR 70S. MINIMA WILL BE DICTATED BY DEG OF DRYING OF LOW-LVL AMS...LKLY IN THE 50S. UPDATE...KRAMAR && .LONG TERM /FRIDAY THROUGH MONDAY/... MDLS CONT TO DEPICT DVLPMNT OF A BROAD SRN CONUS RIDGE FOR THE LONG TERM PD WITH GENL RIDGE AXIS POSITIONING ACRS THE GREAT LAKES. WARMER TEMPS ARE THUS IN STORE FOR THE UPR OH VALLEY REGION WITH WEEKEND READINGS PROGGED WELL INTO THE 80S AS PER HIGHER MOS GUIDANCE. GRADUALLY INCRSG POPS...TO CHC NMBRS FOR THE WEEKEND...WERE ALSO INCLUDED...BUT TIMING WL BE DEPENDENT ON SHRTWV PASSAGE ACRS THE NRN PERIPHERY OF THE RIDGE...SO CONFIDENCE IN THAT PARAMETER IS MINIMAL AT THIS JUNCTURE OF THE FORECAST PROCESS. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... VFR CONDITIONS WILL MOSTLY PREVAIL THROUGH THIS EVENING...ALTHOUGH BRIEF RESTRICTIONS WILL BE POSSIBLE IN ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH THE CHANCE INCREASING TONIGHT. COVERAGE WILL BE SPARSE...ALTHOUGH IF A SHOWER/STORM HITS A TERMINAL VISIBILITY RESTRICTIONS COULD BRIEFLY DROP TO IFR. WINDS WILL BE SOUTHWESTERLY THIS AFTERNOON AT 5-10KTS. WITH A FRONT DROPPING SOUTHWARD TONIGHT...THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE...ALTHOUGH CONFIDENCE IN LOCATION AND AREAL COVERAGE IS TOO LOW TO INCLUDE IN THE TERMINALS AT THIS POINT. A BRIEF PERIOD OF RESTRICTIONS WITH FOG WILL BE POSSIBLE DURING THE PRE-DAWN HOURS ON TUESDAY. IFR CONDITIONS ARE FORECAST ALONG AND SOUTH OF THE BOUNDARY AT KMGW/KZZV WITH MVFR ELSEWHERE. A FRONTAL BOUNDARY WILL PUSH ACROSS THE AREA ON TUESDAY...WITH A BETTER CHANCE OF BRIEF IFR RESTRICTIONS WITH SHOWERS AND THUNDERSTORMS ACROSS THE TERMINALS DURING THE DAY. OUTLOOK.../TUESDAY NIGHT THROUGH FRIDAY/... THE FRONTAL BOUNDARY WILL PUSH SOUTHEAST OF THE AREA TUESDAY NIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO AN END. HIGH PRESSURE WILL THEN BUILD IN FROM THE NORTHWEST...ALLOWING FOR VFR CONDITIONS TO PREVAIL FOR THE MAJORITY ON WEDNESDAY THROUGH FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
250 PM EDT MON JUN 17 2013 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN IN THE VICINITY OF THE UPPER OHIO VALLEY...ALLOWING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO CONTINUE THROUGH THE DAY ON TUESDAY. HIGH PRESSURE WILL THEN MOVE INTO THE REGION FROM THE NORTHWEST...ALLOWING FOR DRY AND SEASONABLE WEATHER FOR WEDNESDAY AND THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... AN ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO INCREASE POPS TO ACCOUNT FOR DEVELOPING UPSTREAM SHOWERS AND THUNDERSTORMS. THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A WEAK AND BROAD CYCLONIC FLOW ACROSS THE UPPER OHIO VALLEY WITH DRIER AND SLIGHTLY WARMER AIR ADVECTING IN FROM THE WEST. 850MB CONVERGENCE ALONG THE MASON-DIXON LINE HAS WEAKENED MOSTLY WITH ONLY AN ISOLATED SHOWER OR TWO REMAINING ACROSS THE ALLEGHENY FRONT. THE CONVERGENCE ZONE HAS BEEN CO-LOCATED WITH A FRONTAL BOUNDARY NEAR THE MASON-DIXON LINE. ALTHOUGH A THERMAL GRADIENT IS LACKING ALONG THE BOUNDARY...IT CAN BE MORE EASILY DEPICTED BY SURFACE DEW POINT AND EQUIVALENT POTENTIAL TEMPERATURE GRADIENTS. UPSTREAM...SOME LAKE BREEZE INTERACTION (LAKE ERIE) WITH A SOUTHWESTERLY LOW-LEVEL FLOW HAS SETUP A CONVERGENCE ZONE OF CONVECTION ACROSS NORTHERN OHIO. THIS EVENING...THE FRONTAL BOUNDARY WILL REMAIN FAIRLY STATIONARY IN THE VICINITY OF THE MASON-DIXON LINE. THERE ARE A FEW CONTRIBUTORS HAT HAVE LED TO THE FORECAST FOR POSSIBLE CONVECTION INTO THE EVENING. THESE INCLUDE...THE FRONTAL BOUNDARY AND INSTABILITY INCREASING TO 1500-2500 J/KG SBCAPE FOR LOCATIONS PRIMARILY SOUTH OF PITTSBURGH. FOR LOCATIONS NORTH AND WEST OF PITTSBURGH...CHC OF THUNDERSTORMS IS FORECAST WITH ONGOING DEVELOPING CONVECTION IN NORTHERN OHIO. WITH THIS AND THE 14Z HRRR IN MIND HAVE GONE WITH SCHC INCREASING TO CHC POP THROUGH MUCH THE EVENING. TONIGHT...LINGERING CONVECTION WILL BE ONGOING FROM DIURNAL ACTIVITY RELATED TO THE SERIES OF BOUNDARIES LOCATED IN THE VICINITY OF THE FORECAST AREA. WITH THE LOSS OF HEATING...CONVECTION WILL BEGIN TO DIMINISH ACROSS THE AREA. HOWEVER...NORTHERN BOUNDARY WILL THEN BEGIN TO DROP SOUTHWARD AS A FRONT. THUS...THE FORCING PROVIDED FROM THIS FEATURE WILL ALLOW FOR THE CHC OF SHOWERS AND THUNDERSTORMS TO CONTINUE ACROSS MUCH OF THE AREA NOCTURNALLY. OVERNIGHT LOWS ARE CLOSER TO THE WARMER MET...WITH LOWS RANGING FROM THE MID 60S IN EASTERN OHIO...SW PA...AND NORTHERN WV TO THE UPPER 50S ACROSS THE ALLEGHENY FRONT AND LAUREL HIGHLANDS. TUESDAY...THE COLD FRONT WILL CONTINUE TO DROP SLOWLY SOUTHWARD ACROSS THE AREA...WITH THE COVERAGE OF SHOWER AND THUNDERSTORMS INCREASING AS A FUNCTION OF DIURNAL HEATING DURING THE DAY. INSTABILITY/SHEAR PROFILES STILL APPEAR TO NOT SUPPORT MORE ORGANIZED CONVECTION AND THUS THE CHANCE OF A STRONG TO SEVERE STORM SEEMS LIMITED AT THIS TIME. TEMP FORECAST CONTINUES TO LEAN TOWARD THE WARMER MET GUIDANCE WITH NAM 850MB TEMPS AROUND 14-15C LEADING TO FORECAST HIGH NEAR 80 ACROSS MUCH OF THE AREA. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... DRY HIGH PRES WILL BEGIN TO BUILD TUESDAY NIGHT AND SUPPRESS PCPN FOR WEDNESDAY AND THURSDAY...BUT SEASONABLY COOL AIR UNDER TROUGHING ALOFT WILL LIMIT TEMP RECOVERY. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... MDLS CONT TO DEPICT DVLPMNT OF A BROAD SRN CONUS RIDGE FOR THE LONG TERM PD WITH GENL RIDGE AXIS POSITIONING ACRS THE GREAT LAKES. WARMER TEMPS ARE THUS IN STORE FOR THE UPR OH VALLEY REGION WITH WEEKEND READINGS PROGGED WELL INTO THE 80S AS PER HIGHER MOS GUIDANCE. GRADUALLY INCRSG POPS...TO CHC NMBRS FOR THE WEEKEND...WERE ALSO INCLUDED...BUT TIMING WL BE DEPENDANT ON SHRTWV PASSAGE ACRS THE NRN PERIPHERY OF THE RIDGE...SO CONFIDENCE IN THAT PARAMETER IS MINIMAL AT THIS JUNCTURE OF THE FORECAST PROCESS. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... VFR CONDITIONS WILL MOSTLY PREVAIL THROUGH THIS EVENING...ALTHOUGH BRIEF RESTRICTIONS WILL BE POSSIBLE IN ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH THE CHANCE INCREASING TONIGHT. COVERAGE WILL BE SPARSE...ALTHOUGH IF A SHOWER/STORM HITS A TERMINAL VISIBILITY RESTRICTIONS COULD BRIEFLY DROP TO IFR. WINDS WILL BE SOUTHWESTERLY THIS AFTERNOON AT 5-10KTS. WITH A FRONT DROPPING SOUTHWARD TONIGHT...THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE...ALTHOUGH CONFIDENCE IN LOCATION AND AREAL COVERAGE IS TOO LOW TO INCLUDE IN THE TERMINALS AT THIS POINT. A BRIEF PERIOD OF RESTRICTIONS WITH FOG WILL BE POSSIBLE DURING THE PRE-DAWN HOURS ON TUESDAY. IFR CONDITIONS ARE FORECAST ALONG AND SOUTH OF THE BOUNDARY AT KMGW/KZZV WITH MVFR ELSEWHERE. A FRONTAL BOUNDARY WILL PUSH ACROSS THE AREA ON TUESDAY...WITH A BETTER CHANCE OF BRIEF IFR RESTRICTIONS WITH SHOWERS AND THUNDERSTORMS ACROSS THE TERMINALS DURING THE DAY. OUTLOOK.../TUESDAY NIGHT THROUGH FRIDAY/... THE FRONTAL BOUNDARY WILL PUSH SOUTHEAST OF THE AREA TUESDAY NIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO AN END. HIGH PRESSURE WILL THEN BUILD IN FROM THE NORTHWEST...ALLOWING FOR VFR CONDITIONS TO PREVAIL FOR THE MAJORITY ON WEDNESDAY THROUGH FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$ SYNOPSIS...WOODRUM NEAR TERM...WOODRUM AVIATION...WOODRUM
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
128 PM EDT MON JUN 17 2013 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN IN THE VICINITY OF THE UPPER OHIO VALLEY...ALLOWING THE CHANCE OF SHOWERS AND THUNDERSTORMS TO CONTINUE THROUGH THE DAY ON TUESDAY. HIGH PRESSURE WILL THEN MOVE INTO THE REGION FROM THE NORTHWEST...ALLOWING FOR DRY AND SEASONABLE WEATHER FOR WEDNESDAY AND THURSDAY. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... AN ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO DECREASE POPS SOUTH OF THE MASON-DIXON LINE EARLY THIS AFTERNOON. THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A WEAK AND BROAD CYCLONIC FLOW ACROSS THE UPPER OHIO VALLEY WITH DRIER AND SLIGHTLY WARMER AIR ADVECTING IN FROM THE WEST. 850MB CONVERGENCE ALONG THE MASON-DIXON LINE HAS WEAKENED MOSTLY WITH ONLY AN ISOLATED SHOWER OR TWO REMAINING ACROSS THE ALLEGHENY FRONT. THE CONVERGENCE ZONE HAS BEEN CO-LOCATED WITH A FRONTAL BOUNDARY NEAR THE MASON-DIXON LINE. ALTHOUGH A THERMAL GRADIENT IS LACKING ALONG THE BOUNDARY...IT CAN BE MORE EASILY DEPICTED BY SURFACE DEW POINT AND EQUIVALENT POTENTIAL TEMPERATURE GRADIENTS. THIS AFTERNOON...THE FRONTAL BOUNDARY WILL REMAIN FAIRLY STATIONARY IN THE VICINITY OF THE MASON-DIXON LINE. THERE ARE TWO POTENTIAL CONTRIBUTORS THAT HAVE LED TO THE FORECAST FOR POSSIBLE ISOLATED CONVECTION THIS AFTERNOON...THE FRONTAL BOUNDARY AND INSTABILITY INCREASING TO 1500-2500 J/KG SBCAPE PRIMARILY SOUTH OF PITTSBURGH. WITH THIS AND THE 14Z HRRR IN MIND HAVE GONE WITH SCHC POP THROUGH MUCH OF THE AFTERNOON/EVENING. FOR TEMPS...UTILIZED RECENT TRENDS IN OBS ALONG WITH RAP 850MB TEMPS TO GO A FEW DEGREES ABOVE A MAV/MET BLEND. HIGHS TODAY WILL REACH THE LOWER 80S ACROSS MOST LOCATIONS WITH HIGHS IN THE MID 70S ACROSS THE HIGHER ELEVATIONS OF WV/MD. && .SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY/... CHC POPS WERE MAINTAINED TONIGHT...BUT SHIFTED SWD INTO TUESDAY AS SECONDARY FRONT/OUTFLOW PROGRESS AS ANOTHER DISTURBANCE/JET STREAK CROSS THE REGION. DRY HIGH PRES WL BLD THEREAFTER AND SUPPRESS PCPN FOR WEDNESDAY AND THURSDAY...BUT SEASONABLY COOL AIR UNDR TROFG ALOFT WL LIMIT TEMP RECOVERY. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... MDLS CONT TO DEPICT DVLPMNT OF A BROAD SRN CONUS RIDGE FOR THE LONG TERM PD WITH GENL RIDGE AXIS POSITIONING ACRS THE GREAT LAKES. WARMER TEMPS ARE THUS IN STORE FOR THE UPR OH VALLEY REGION WITH WEEKEND READINGS PROGGED WELL INTO THE 80S AS PER HIGHER MOS GUIDANCE. GRADUALLY INCRSG POPS...TO CHC NMBRS FOR THE WEEKEND...WERE ALSO INCLUDED...BUT TIMING WL BE DEPENDANT ON SHRTWV PASSAGE ACRS THE NRN PERIPHERY OF THE RIDGE...SO CONFIDENCE IN THAT PARAMETER IS MINIMAL AT THIS JUNCTURE OF THE FORECAST PROCESS. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... VFR CONDITIONS WILL MOSTLY PREVAIL THROUGH THIS EVENING...ALTHOUGH BRIEF RESTRICTIONS WILL BE POSSIBLE IN ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH THE CHANCE INCREASING TONIGHT. HAVE NOT INCLUDED THUNDERSTORMS IN THE TAFS THROUGH 12Z AT THIS MOMENT AS COVERAGE WILL BE TOO SPARSE...ALTHOUGH IF A SHOWER/STORM HITS A TERMINAL VISIBILITY RESTRICTIONS COULD BRIEFLY DROP TO IFR. WINDS WILL BE SOUTHWESTERLY THIS AFTERNOON AT 5-10KTS. A BRIEF PERIOD OF RESTRICTIONS WITH FOG/MIST WILL BE POSSIBLE DURING THE PRE-DAWN HOURS ON TUESDAY. IFR CONDITIONS ARE FORECAST ALONG AND SOUTH OF THE BOUNDARY AT KMGW/KZZV WITH MVFR ELSEWHERE. A FRONTAL BOUNDARY WILL PUSH ACROSS THE AREA ON TUESDAY...WITH A BETTER CHANCE OF BRIEF IFR RESTRICTIONS WITH SHOWERS AND THUNDERSTORMS ACROSS THE TERMINALS DURING THE DAY. OUTLOOK.../TUESDAY NIGHT THROUGH FRIDAY/... THE FRONTAL BOUNDARY WILL PUSH SOUTHEAST OF THE AREA TUESDAY NIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO AN END. HIGH PRESSURE WILL THEN BUILD IN FROM THE NORTHWEST...ALLOWING FOR VFR CONDITIONS TO PREVAIL FOR THE MAJORITY ON WEDNESDAY THROUGH FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$ SYNOPSIS...WOODRUM NEAR TERM...WOODRUM AVIATION...WOODRUM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1203 AM EDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 409 PM EDT TUE JUN 18 2013 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BETWEEN A TROUGH OVER QUEBEC AND A RIDGE FROM THE ROCKIES INTO THE WRN PLAINS. AT THE SFC...A RIDGE EXTENDED FROM JAMES BAY TO LAKE SUPERIOR. WITH THE DRY AIRMASS OVER THE REGION (PWAT AROUND 0.50 OR ABOUT 50 PCT OF NORMAL)...A WEAK SHORTWAVE TROUGH INTO WRN LAKE SUPERIOR ONLY SUPPORTED A PATCH OF MID/HIGH CLOUDS. TONIGHT...HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION KEEPING CONDITIONS DRY UNDER MOSTLY CLEAR SKIES. AS THE RIDGE AXIS SLIDES SE OVERNIGHT...LIGHT RETURN SRLY FLOW WILL RESULT IN A BIT MORE MIXING ESPECIALLY OVER THE FAR WEST AND ALONG THE LAKE SUPERIOR SHORELINE. LOOK FOR MIN TEMPS TO RANGE FROM AROUND 40 INLAND TO THE MID TO UPPER 40S ALONG THE GREAT LAKES SHORELINES. WEDNESDAY...AS THE RIDGE SLOWLY SLIDES OFF TO THE EAST...SRLY WINDS WILL INCREASE. 850 MB TEMPS AROUND 10C AND MIXING TO AROUND 800 MB WILL SUPPORT TEMPS INTO THE MID 70S INLAND...EXCEPT NEAR LAKE MICHIGAN WHERE ONSHORE FLOW KEEPS READINGS IN THE 60S. ALTHOUGH MOISTURE WILL ALSO INCREASE SLIGHTLY...THE HIGHER LOW LEVEL THETA-E AXIS TO SUPPORT SHRA/TSRA WITH WEAK SHRTWVS IN NW FLOW IS EXPECTED TO REMAIN WEST OF THE CWA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 409 PM EDT TUE JUN 18 2013 AREA WILL BE UNDER NORTHWEST FLOW ALOFT TO START THE PERIOD AS THE UPPER GREAT LAKES IS ON THE EASTERN SIDE OF THE RIDGE OVER THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. A WEAK SHORTWAVE WILL BE SLIDING ACROSS NORTHEAST LAKE SUPERIOR ON WEDNESDAY NIGHT...WHILE A SURFACE TROUGH DROPS SOUTHEAST ACROSS THE CWA DURING THE OVERNIGHT PERIOD. THERE WILL LIKELY BE SOME SHOWERS AND A FEW THUNDERSTORMS WITH THIS TROUGH ON WEDNESDAY NIGHT AND WILL FOLLOW A GENERAL CONSENSUS FOR THE TIMING OF THE POPS AS IT MOVES IN. THIS FRONT LOOKS TO STALL ACROSS UPPER MICHIGAN ON THURSDAY AND WILL COMBINE WITH DEVELOPING LAKE BREEZES TO PRODUCE AFTERNOON SHOWERS AND THUNDERSTORMS. THE STRENGTH OF THESE THUNDERSTORMS WILL DEPEND ON THE AMOUNT OF DIURNAL HEATING...INCREASING SOUTHERLY FLOW WITH A DEVELOPING WARM FRONT ON THE BOUNDARY...AND THE ARRIVAL OF THE ANOTHER WEAK SHORTWAVE DURING THE LATE AFTERNOON AND EVENING. ML CAPE VALUES OF 500-1000 J/KG OVER THE WESTERN 2/3RDS OF THE CWA AND 0-6KM BULK SHEAR VALUES AROUND 30KTS SUPPORTS THUNDERSTORMS AND SOME TILTING OF THE UPDRAFTS. HEAVY RAIN AND SMALL HAIL WILL BE THE PRIMARY THREATS...AS NCAPE VALUES AROUND .1 SHOULD KEEP ANY HAIL FROM GROWING TOO LARGE. WILL CONTINUE TO HIGHLIGHT THE HIGHEST POPS OVER THE INTERIOR WEST/CENTRAL...CLOSEST TO LAKE SUPERIOR LAKE BREEZE AND THEN FOLLOW THE STORM MOTION TO THE SOUTHEAST. THURSDAY NIGHT THROUGH THE WEEKEND IS SHAPING UP TO BE A FAIRLY ACTIVE PATTERN FOR THUNDERSTORMS IN THE UPPER MISSISSIPPI VALLEY AND UPPER GREAT LAKES REGION. THIS IS DUE TO THE UPPER RIDGE GRADUALLY SHIFTING EAST INTO THE UPPER GREAT LAKES. MEANWHILE...WEAK SURFACE LOW WILL REMAIN FAIRLY STATIONARY OVER THE CENTRAL/NORTHERN PLAINS. FROM THIS LOW...A WARM FRONT WILL LOOKS TO SETUP FROM THE STALLED TROUGH ON THURSDAY AND REMAIN LOCATED AROUND THE UPPER GREAT LAKES REGION THROUGH THE WEEKEND. LOOKING AT THIS LARGE SCALE PATTERN...IT IS VERY CONDUCIVE PERIODS OF SHOWERS AND POTENTIALLY STRONG THUNDERSTORMS. BUT TRYING TO PIN DOWN THE EXACT LOCATION AND TIMING IS DIFFICULT DUE TO THE VARIABILITY OF THE SHORTWAVES AND POSITION OF THE WARM FRONT. INSTABILITY WILL GRADUALLY GROW FROM FRIDAY INTO THE WEEKEND...AS PERSISTENT SOUTHWESTERLY FLOW AHEAD OF THE LOW PULLS PLENTY OF GULF MOISTURE INTO THE AREA. USING ML CAPE VALUES TO REMOVE SOME OF THE LOW LEVEL MOIST BIASES IN THE MODELS FOR FRIDAY INTO THE WEEKEND...THERE ARE STILL SOME DECENT VALUES FOR U.P. STANDARDS. FRIDAY THEY LOOK TO PEAK IN THE 750-1500 J/KG RANGE OVER THE WEST AND THEN GROW TO 1500-2500 J/KG FOR SAT/SUN DEPENDING ON THE MODEL. THE GFS IS THE MOST AGGRESSIVE ON THE NORTHWARD EXTENT OF THE WARM FRONT...WHILE THE GEM/ECMWF TRY TO KEEP THE FRONT A TOUCH SOUTH OF THE AREA. IT WILL PROBABLY BE A VARIETY OF THUNDERSTORM TYPES DURING THAT PERIOD. CONVECTIVE COMPLEXES MOVING EAST /VIA FORWARD PROP CORFIDI VECTORS/ AROUND THE RIDGE WILL LIKELY BE THE MAIN THREAT...BUT WITH THE INSTABILITY PRESENT AND LIMITED INHIBITION...DIURNAL THUNDERSTORMS WILL ALSO BE POSSIBLE. THE ONLY CONCERNS WOULD BE IF THE RIDGE AND WARM FRONT BUILD FAR ENOUGH NORTH TO SLIDE MOST OF THE THUNDERSTORM COMPLEXES NORTH OF UPPER MICHIGAN OR THE MORE LIKELY SCENARIO OF IT BECOMING HUNG UP SOUTH OF THE AREA /ESPECIALLY AS CONVECTION HOLDS THEM SOUTH/. WITH THE GROWING CONFIDENCE...WILL ADD A MENTION OF STRONG THUNDERSTORMS FOR THE WEEKEND IN BOTH THE HWO AND EHWO. HEAVY RAIN IS ALSO POSSIBLE DURING THIS PERIOD WITH THE THUNDERSTORMS...AS PWAT VALUES RISE ABOVE 1.5 INCHES WHICH IS WELL ABOVE THE 75TH PERCENTILE FOR CLIMATOLOGY FOR THIS AREA. IT WILL BE PRETTY HUMID FOR FRIDAY INTO THE WEEKEND /DEWPOINTS IN THE UPPER 50S AND 60S/ AND THE TEMPERATURES WILL DEPEND ON THE POSITIONING OF THE WARM FRONT. WILL CONTINUE TO SHOW TEMPS IN THE MID 70S TO LOWER 80S FOR MOST LOCATIONS...WITH THE WARMEST VALUES NEAR THE WISCONSIN BORDER. IF THE GFS ENDS UP BEING CORRECT...WOULD HAVE TO BUMP TEMPS UP WELL INTO THE 80S FOR THE END OF THE WEEKEND. UNCERTAINTY REALLY GROWS HEADING INTO MONDAY/TUESDAY...AS A LOT DEPENDS ON THE WEEKEND WEATHER. THE GENERAL IDEA FROM THE MODELS IS THAT THE RIDGE BREAKS DOWN AND THE AREA WILL BE UNDER ZONAL FLOW ALOFT. THIS WILL CONTINUE TO BRING WAVES ACROSS THE AREA AND KEEP THE THUNDERSTORM POTENTIAL IN PLACE FOR THAT PERIOD. AT THIS TIME...MODELS ARE INDICATING A COLD FRONT DROPPING SOUTH OUT OF CANADA ON WEDNESDAY...WHICH MAY BRING AN END TO THE WARM/HUMID WEATHER. FINALLY...WILL CONTINUE TO MENTION PATCHY FOG DEVELOPING ON LAKE SUPERIOR ON WEDNESDAY NIGHT AND THEN CONTINUING INTO EARLY NEXT WEEK. WILL LIKELY NEED TO EXPAND IT TO AREAS OR EVEN DENSE FOG AS IT NEARS. ALSO...ADDED A MENTION OF FOG OVER LAKE MICHIGAN NEARSHORE AREAS STARTING LATE THURSDAY NIGHT AS THE PRECIPITATION AND HIGHER DEWPOINTS START TO AFFECT THAT AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1203 AM EDT WED JUN 19 2013 WITH HIGH PRESSURE IN CONTROL...VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 409 PM EDT TUE JUN 18 2013 NO SIGNIFICANT PRESSURE CHANGES THROUGH THE PERIOD WILL RESULT IN WINDS BELOW 25 KT...OUTSIDE OF ANY THUNDERSTORMS WHICH ARE POSSIBLE FROM WEDNESDAY NIGHT THROUGH SUNDAY. INCREASING LOW LEVEL MOISTURE INTO THE REGION FROM AFTER WEDNESDAY...WILL RESULT IN AREAS OF FOG...POSSIBLY DENSE AT TIMES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
728 PM EDT TUE JUN 18 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 409 PM EDT TUE JUN 18 2013 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BETWEEN A TROUGH OVER QUEBEC AND A RIDGE FROM THE ROCKIES INTO THE WRN PLAINS. AT THE SFC...A RIDGE EXTENDED FROM JAMES BAY TO LAKE SUPERIOR. WITH THE DRY AIRMASS OVER THE REGION (PWAT AROUND 0.50 OR ABOUT 50 PCT OF NORMAL)...A WEAK SHORTWAVE TROUGH INTO WRN LAKE SUPERIOR ONLY SUPPORTED A PATCH OF MID/HIGH CLOUDS. TONIGHT...HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION KEEPING CONDITIONS DRY UNDER MOSTLY CLEAR SKIES. AS THE RIDGE AXIS SLIDES SE OVERNIGHT...LIGHT RETURN SRLY FLOW WILL RESULT IN A BIT MORE MIXING ESPECIALLY OVER THE FAR WEST AND ALONG THE LAKE SUPERIOR SHORELINE. LOOK FOR MIN TEMPS TO RANGE FROM AROUND 40 INLAND TO THE MID TO UPPER 40S ALONG THE GREAT LAKES SHORELINES. WEDNESDAY...AS THE RIDGE SLOWLY SLIDES OFF TO THE EAST...SRLY WINDS WILL INCREASE. 850 MB TEMPS AROUND 10C AND MIXING TO AROUND 800 MB WILL SUPPORT TEMPS INTO THE MID 70S INLAND...EXCEPT NEAR LAKE MICHIGAN WHERE ONSHORE FLOW KEEPS READINGS IN THE 60S. ALTHOUGH MOISTURE WILL ALSO INCREASE SLIGHTLY...THE HIGHER LOW LEVEL THETA-E AXIS TO SUPPORT SHRA/TSRA WITH WEAK SHRTWVS IN NW FLOW IS EXPECTED TO REMAIN WEST OF THE CWA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 409 PM EDT TUE JUN 18 2013 AREA WILL BE UNDER NORTHWEST FLOW ALOFT TO START THE PERIOD AS THE UPPER GREAT LAKES IS ON THE EASTERN SIDE OF THE RIDGE OVER THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. A WEAK SHORTWAVE WILL BE SLIDING ACROSS NORTHEAST LAKE SUPERIOR ON WEDNESDAY NIGHT...WHILE A SURFACE TROUGH DROPS SOUTHEAST ACROSS THE CWA DURING THE OVERNIGHT PERIOD. THERE WILL LIKELY BE SOME SHOWERS AND A FEW THUNDERSTORMS WITH THIS TROUGH ON WEDNESDAY NIGHT AND WILL FOLLOW A GENERAL CONSENSUS FOR THE TIMING OF THE POPS AS IT MOVES IN. THIS FRONT LOOKS TO STALL ACROSS UPPER MICHIGAN ON THURSDAY AND WILL COMBINE WITH DEVELOPING LAKE BREEZES TO PRODUCE AFTERNOON SHOWERS AND THUNDERSTORMS. THE STRENGTH OF THESE THUNDERSTORMS WILL DEPEND ON THE AMOUNT OF DIURNAL HEATING...INCREASING SOUTHERLY FLOW WITH A DEVELOPING WARM FRONT ON THE BOUNDARY...AND THE ARRIVAL OF THE ANOTHER WEAK SHORTWAVE DURING THE LATE AFTERNOON AND EVENING. ML CAPE VALUES OF 500-1000 J/KG OVER THE WESTERN 2/3RDS OF THE CWA AND 0-6KM BULK SHEAR VALUES AROUND 30KTS SUPPORTS THUNDERSTORMS AND SOME TILTING OF THE UPDRAFTS. HEAVY RAIN AND SMALL HAIL WILL BE THE PRIMARY THREATS...AS NCAPE VALUES AROUND .1 SHOULD KEEP ANY HAIL FROM GROWING TOO LARGE. WILL CONTINUE TO HIGHLIGHT THE HIGHEST POPS OVER THE INTERIOR WEST/CENTRAL...CLOSEST TO LAKE SUPERIOR LAKE BREEZE AND THEN FOLLOW THE STORM MOTION TO THE SOUTHEAST. THURSDAY NIGHT THROUGH THE WEEKEND IS SHAPING UP TO BE A FAIRLY ACTIVE PATTERN FOR THUNDERSTORMS IN THE UPPER MISSISSIPPI VALLEY AND UPPER GREAT LAKES REGION. THIS IS DUE TO THE UPPER RIDGE GRADUALLY SHIFTING EAST INTO THE UPPER GREAT LAKES. MEANWHILE...WEAK SURFACE LOW WILL REMAIN FAIRLY STATIONARY OVER THE CENTRAL/NORTHERN PLAINS. FROM THIS LOW...A WARM FRONT WILL LOOKS TO SETUP FROM THE STALLED TROUGH ON THURSDAY AND REMAIN LOCATED AROUND THE UPPER GREAT LAKES REGION THROUGH THE WEEKEND. LOOKING AT THIS LARGE SCALE PATTERN...IT IS VERY CONDUCIVE PERIODS OF SHOWERS AND POTENTIALLY STRONG THUNDERSTORMS. BUT TRYING TO PIN DOWN THE EXACT LOCATION AND TIMING IS DIFFICULT DUE TO THE VARIABILITY OF THE SHORTWAVES AND POSITION OF THE WARM FRONT. INSTABILITY WILL GRADUALLY GROW FROM FRIDAY INTO THE WEEKEND...AS PERSISTENT SOUTHWESTERLY FLOW AHEAD OF THE LOW PULLS PLENTY OF GULF MOISTURE INTO THE AREA. USING ML CAPE VALUES TO REMOVE SOME OF THE LOW LEVEL MOIST BIASES IN THE MODELS FOR FRIDAY INTO THE WEEKEND...THERE ARE STILL SOME DECENT VALUES FOR U.P. STANDARDS. FRIDAY THEY LOOK TO PEAK IN THE 750-1500 J/KG RANGE OVER THE WEST AND THEN GROW TO 1500-2500 J/KG FOR SAT/SUN DEPENDING ON THE MODEL. THE GFS IS THE MOST AGGRESSIVE ON THE NORTHWARD EXTENT OF THE WARM FRONT...WHILE THE GEM/ECMWF TRY TO KEEP THE FRONT A TOUCH SOUTH OF THE AREA. IT WILL PROBABLY BE A VARIETY OF THUNDERSTORM TYPES DURING THAT PERIOD. CONVECTIVE COMPLEXES MOVING EAST /VIA FORWARD PROP CORFIDI VECTORS/ AROUND THE RIDGE WILL LIKELY BE THE MAIN THREAT...BUT WITH THE INSTABILITY PRESENT AND LIMITED INHIBITION...DIURNAL THUNDERSTORMS WILL ALSO BE POSSIBLE. THE ONLY CONCERNS WOULD BE IF THE RIDGE AND WARM FRONT BUILD FAR ENOUGH NORTH TO SLIDE MOST OF THE THUNDERSTORM COMPLEXES NORTH OF UPPER MICHIGAN OR THE MORE LIKELY SCENARIO OF IT BECOMING HUNG UP SOUTH OF THE AREA /ESPECIALLY AS CONVECTION HOLDS THEM SOUTH/. WITH THE GROWING CONFIDENCE...WILL ADD A MENTION OF STRONG THUNDERSTORMS FOR THE WEEKEND IN BOTH THE HWO AND EHWO. HEAVY RAIN IS ALSO POSSIBLE DURING THIS PERIOD WITH THE THUNDERSTORMS...AS PWAT VALUES RISE ABOVE 1.5 INCHES WHICH IS WELL ABOVE THE 75TH PERCENTILE FOR CLIMATOLOGY FOR THIS AREA. IT WILL BE PRETTY HUMID FOR FRIDAY INTO THE WEEKEND /DEWPOINTS IN THE UPPER 50S AND 60S/ AND THE TEMPERATURES WILL DEPEND ON THE POSITIONING OF THE WARM FRONT. WILL CONTINUE TO SHOW TEMPS IN THE MID 70S TO LOWER 80S FOR MOST LOCATIONS...WITH THE WARMEST VALUES NEAR THE WISCONSIN BORDER. IF THE GFS ENDS UP BEING CORRECT...WOULD HAVE TO BUMP TEMPS UP WELL INTO THE 80S FOR THE END OF THE WEEKEND. UNCERTAINTY REALLY GROWS HEADING INTO MONDAY/TUESDAY...AS A LOT DEPENDS ON THE WEEKEND WEATHER. THE GENERAL IDEA FROM THE MODELS IS THAT THE RIDGE BREAKS DOWN AND THE AREA WILL BE UNDER ZONAL FLOW ALOFT. THIS WILL CONTINUE TO BRING WAVES ACROSS THE AREA AND KEEP THE THUNDERSTORM POTENTIAL IN PLACE FOR THAT PERIOD. AT THIS TIME...MODELS ARE INDICATING A COLD FRONT DROPPING SOUTH OUT OF CANADA ON WEDNESDAY...WHICH MAY BRING AN END TO THE WARM/HUMID WEATHER. FINALLY...WILL CONTINUE TO MENTION PATCHY FOG DEVELOPING ON LAKE SUPERIOR ON WEDNESDAY NIGHT AND THEN CONTINUING INTO EARLY NEXT WEEK. WILL LIKELY NEED TO EXPAND IT TO AREAS OR EVEN DENSE FOG AS IT NEARS. ALSO...ADDED A MENTION OF FOG OVER LAKE MICHIGAN NEARSHORE AREAS STARTING LATE THURSDAY NIGHT AS THE PRECIPITATION AND HIGHER DEWPOINTS START TO AFFECT THAT AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 728 PM EDT TUE JUN 18 2013 WITH HIGH PRESSURE IN CONTROL...VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 409 PM EDT TUE JUN 18 2013 NO SIGNIFICANT PRESSURE CHANGES THROUGH THE PERIOD WILL RESULT IN WINDS BELOW 25 KT...OUTSIDE OF ANY THUNDERSTORMS WHICH ARE POSSIBLE FROM WEDNESDAY NIGHT THROUGH SUNDAY. INCREASING LOW LEVEL MOISTURE INTO THE REGION FROM AFTER WEDNESDAY...WILL RESULT IN AREAS OF FOG...POSSIBLY DENSE AT TIMES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
453 AM EDT MON JUN 17 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 411 PM EDT SUN JUN 16 2013 THE MAIN CONCERN FOR THE SHORT TERM FORECAST WILL BE THE ONGOING SHOWERS AND THUNDERSTORMS AND ADDITIONAL SHOWERS WITH THE TROUGH DROPPING SOUTH ACROSS THE AREA TONIGHT. INITIAL CONVECTION WAS OVER EASTERN UPPER MICHIGAN...WHERE THERE WAS INCREASED MOISTURE FROM THE FOG EARLIER TODAY AND CONVERGENCE FROM WEAK LAKE BREEZES. THESE INITIAL SHOWERS HAVE SHIFTED TO THE SOUTHEAST AND OUT OF THE CWA...BUT ARE SEEING SOME SHOWERS IN CENTRAL UPPER MICHIGAN ALONG THE LAKE SUPERIOR LAKE BREEZE. THESE SHOWERS HAVE BEEN LIMITED THUS FAR DUE TO THE DRY MID LEVEL AIR EVEN THOUGH THERE IS STRONG LOW LEVEL LAPSE RATES AND RAP ANALYZED SB CAPE VALUES OF 500-1000 J/KG. BUT WITH THE INVERTED V LOOK TO THE RAP SOUNDINGS...ML CAPES ARE STRUGGLING TO GET MUCH ABOVE 250-500 J/KG. THIS DRY AIR CAN ALSO BE SEEN IN THE DEWPOINTS /UPPER 40S/ AWAY FROM THE INFLUENCE OF THE GREAT LAKES. THERE HAVE EVEN BEEN SOME SIGNIFICANT JUMPS IN THE DEWPOINTS OVER THE EASTERN CWA...AS THE LAKE BREEZES HAVE MOVED IN AND OUT OF SOME OF THE SITES. FARTHER WEST...A PERSISTENT SHOWER/THUNDERSTORM CLUSTER MOVED INTO WESTERN GOGEBIC COUNTY OVER THE LAST HOUR AND DID PRODUCE SOME GUSTS UP TO 40KTS EVEN THOUGH THE CLUSTER IS DIMINISHING. THIS ISN/T TOO UNREASONABLE WITH CURRENT DCAPE VALUES OVER MUCH OF UPPER MICHIGAN AROUND 800-1000 J/KG AND THE INVERTED V SOUNDINGS. WOULD EXPECT THIS TO BE THE PRIMARY CONCERN FOR ANY SHOWERS/THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. FINALLY...ADDITIONAL SHOWERS/THUNDERSTORMS HAVE BEEN ONGOING JUST NORTHEAST OF LAKE SUPERIOR...DUE TO ONE PIECE OF SHEARED OFF UPPER LEVEL ENERGY DROPPING SOUTHEAST ALONG THE TROUGH. THESE SHOWERS WILL CONTINUE QUICKLY SOUTHEAST AS THE STORM MOTION IS AROUND 40KTS. THE AREA THAT WILL BRING THE BEST CHANCE FOR SHOWERS IS THE REMNANT SHORTWAVE FROM THE UPPER LOW THAT WAS IN CENTRAL SASKATCHEWAN YESTERDAY. THIS SHORTWAVE HAS STARTED TO MOVE TOWARDS THE CANADA/ND/MN BORDER AND HAS SPARKED SHOWERS AND THUNDERSTORMS ALONG THE SURFACE TROUGH WHERE THERE IS DEEPER MOISTURE. WITH THE STORM MOTION TO THE SOUTHEAST AROUND 30-35KTS AND THE TROUGH SLOWLY SAGGING SOUTHEAST...WOULD EXPECT THOSE SHOWERS TO MOVE SOUTHEAST ACROSS WESTERN/CENTRAL UPPER MICHIGAN LATE THIS AFTERNOON AND INTO THE EVENING HOURS. NOT ENTIRELY CONFIDENT ON THE EASTERN CWA...AS IT WILL DEPEND ON THE THUNDERSTORMS CURRENTLY MOVING SOUTHEAST FROM THUNDER BAY AND HOW FAR SOUTHEAST THEY WILL MAKE IT BEFORE DIMINISHING. WILL HAVE LOWER POPS THAN OVER THE WEST...BUT STILL IN THE LOW END CHANCE CATEGORY. AN EARLIER UPDATE COVERED THE TIMING WELL OVER THE WEST AND HAVE JUST MADE MINOR TWEAKS TO MATCH THE CURRENT CONDITIONS...WITH MOST AREAS IN THE HIGHER REACHES OF THE SCATTERED/CHANCE CATEGORY. THINK THERE IS A DECENT SHOT MOST LOCATIONS WILL SEE RAIN...BUT THE COVERAGE/TIMING WOULD BE BETTER REFLECTED IN THE SCATTERED WORDING. AS MENTIONED ABOVE...THE DRY AIR AND LIMITED INSTABILITY WILL BE THE MAIN LIMITING FACTORS TO THE THUNDERSTORMS AND THEIR SEVERE POTENTIAL. BEST THREAT WILL BE WEST-SOUTHWEST OF THE CWA WHERE THE 850-700/500MB LAPSE RATES ARE THE STEEPEST...BUT THERE COULD BE SOME STRONGER STORMS OVER THE SOUTHWEST THIRD OF THE CWA. HAIL POTENTIAL WILL BE LIMITED DUE TO THE LIMITED INSTABILITY AND TALL/SKINNY CAPE. AS MENTIONED ABOVE...GUSTY WINDS WILL BE THE BIGGEST THREAT OVER THE SW HALF OF THE CWA...AS THEY HAVE THE STEEPER MID LEVEL LAPSE RATES...COMBINED WITH THE DRY LOW LEVELS TO PRODUCE THE HIGHER DCAPE VALUES. THEN...AS THE SHORTWAVE TRACKS SOUTHEAST INTO NORTHWEST WISCONSIN TONIGHT AND THE REST OF NORTHERN WISCONSIN ON MONDAY MORNING...WOULD EXPECT SCATTERED SHOWERS TO CONTINUE THROUGH THE NIGHT OVER THE SOUTHWEST HALF OF THE CWA. THAT IS ALSO WHERE THE BEST 850-500MB Q-VECTOR CONV IS LOCATED EVEN THOUGH THE DEEPER MOISTURE IS OVER EASTERN UPPER MICHIGAN. HAVE SLOWLY DIMINISHED THE THUNDER THREAT OVERNIGHT AND INTO MONDAY MORNING TO BE OVER THE SOUTHERN PART OF THE CWA...WHERE THE BETTER FORCING IS LOCATED. WILL HOLD ON TO SOME LIGHT RAIN SHOWERS OVER NORTHERN UPPER MICHIGAN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING...AS LOW LEVEL CONVERGENCE INCREASES WITH THE WINDS SHIFTING TO THE NORTH-NORTHEAST. WITH DECENT MOISTURE BELOW 10KFT AS THAT CONVERGENCE OCCURS...THINKING THERE WILL BE ENOUGH TO PRODUCE SOME SHOWERS...ESPECIALLY OVER SOME OF THE HIGHER TERRAIN LOCATIONS OF NORTH CENTRAL UPPER MICHIGAN WHERE THE WINDS BECOME UPSLOPE FOR A PERIOD OF TIME. THE LARGER SCALE FORCING SHOULD DEPART THE SOUTHWEST AND SOUTH CENTRAL CWA AROUND DAYBREAK AND THEY WILL BE LEFT WITH ANY SHOWERS DROPPING SOUTH ALONG THE ENHANCED CONVERGENCE. BEHIND THE TROUGH...LOW CLOUDS SEEN IN CENTRAL ONTARIO/MANITOBA THIS MORNING WILL MOVE SOUTH ACROSS THE CWA LATE TONIGHT INTO TOMORROW MORNING. MODELS STRUGGLING WITH HOW LOW THE CLOUDS WILL BE...BUT EITHER WAY A CLOUDY START TO THE WORK WEEK IS EXPECTED. CANADIAN HIGH PRESSURE IS EXPECTED TO BUILD OVER THE AREA ON MONDAY AFTERNOON...BRINGING DRIER AIR AND SUBSIDENCE TO THE AREA IN THE AFTERNOON. THIS WILL PRODUCE DECREASING CLOUDS FROM NORTH TO SOUTH. HIGHS WILL BE MUCH COOLER TOMORROW...WITH 60S IN MOST LOCATIONS EXCEPT NEAR LAKE SUPERIOR WHERE NORTHERLY FLOW OFF THE LAKE WILL KEEP HIGHS IN THE UPPER 50S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 452 AM EDT MON JUN 17 2013 TAKING A LOOK AT FCST SOUNDINGS...TUESDAY THROUGH EARLY WEDNESDAY SHOULD BE PRETTY DRY WITH LITTLE TO NO CLOUDS IN THE SKY. WILL KEEP THE 0 POPS GOING. OTHER THAN THE TYPICAL LAKE BREEZES...WITH HIGH PRESSURE DIRECTLY OVERHEAD...WINDS WILL BE LIGHT. WILL LIKELY BE ABLE TO MIX UP TO 800MB...OR HIGHER...RESULTING IN AFTERNOON RH VALUES IN THE 20 PERCENT RANGE FOR MOST OF UPPER MI...FIRE CONCERNS SHOULD REMAIN IN CHECK HOWEVER WITH THE RELATIVELY LIGHT WINDS. EXPECT THE WARMING TREND TO CONTINUE INTO WEDNESDAY...WITH INCREASED W-SW FLOW THROUGH 750MB...AS THE SFC HIGH SHIFTS TOWARD THE LOWER GREAT LAKES. 850MB TEMPS SHOULD RISE FROM A CWA AVERAGE OF 7C TUESDAY AFTERNOON TO AROUND 12C BY LATE WEDNESDAY AFTERNOON. WITH NW FLOW ALOFT...EXPECT A FEW PESKY WAVES IN THE MEAN FLOW TO SLIDE ACROSS THE CWA. THE NEXT SIGNIFICANT ONE WILL LINE UP WITH THE NEARING OF A WEAK SFC LOW PUSHING OVER ONTARIO WEDNESDAY...AND INTO QUEBEC LATE WEDNESDAY NIGHT INTO THURSDAY. THE WEAK COLD FRONT SHOULD BE PRETTY WASHED OUT AS IT NEARS LAKE SUPERIOR WEDNESDAY NIGHT. A FEW SHOWERS AND POSSIBLY THUNDERSTORMS ACROSS MN AND WESTERN WI WEDNESDAY MORNING WILL LIKELY BE WINDING DOWN AS THEY HEAD TOWARD UPPER MI. 200-500 J/KG CAPE VALUES OVER FAR W UPPER MI BETWEEN 18Z WED AND 00Z THUR SHOULD BE ALL BUT GONE BY 06Z THURSDAY. MOISTURE LOOKS TO BE VERY LIMITED...WITH ANY GOLF MOISTURE STUCK ACROSS THE GULF STATES. EXPECT THE WEAK COLD FRONT TO SINK SOUTH OF THE CWA BY THE END OF THE DAY THURSDAY. THE MAIN RESULT WILL BE CLOUD COVER AND A WIND SHIFT...AND EVEN THROUGH WE DO HAVE 30-40 PERCENT POPS THEY WILL LIKELY RESULT IN LOW AMOUNTS OF PRECIP WITH AROUND A TENTH OF AN INCH OR LESS EXPECTED FOR MOST LOCATIONS. HIGH PRESSURE SET UP ACROSS MUCH OF N AND CENTRAL ONTARIO THURSDAY MORNING WILL EXTEND A RIDGE ACROSS LAKE SUPERIOR BY LATE THURSDAY MORNING...AND MUCH OF THE CWA BY 00Z FRIDAY. THE 500MB RIDGE ACROSS THE PLAINS STATES WILL CONTINUE TO BUILD THURSDAY...IN ADVANCE OF THE 500MB LOW STUCK SPINNING OVER THE PACIFIC NORTHWEST...AND SFC LOW ORGANIZING OFF THE ROCKY MOUNTAIN FRONT. WENT AHEAD AND BROKE UP THE THURSDAY NIGHT PERIOD TO INCLUDE A BIT MORE DRYING WEATHER THURSDAY EVENING. THE CLOSEST THE SFC LOW WILL LIKELY GET TO UPPER MI WILL BE MN AND S WI...ON SATURDAY. STILL...MUCH OF OUR WEATHER FOR FRIDAY THROUGH THE WEEKEND WILL REVOLVED AROUND THE 500MB FLOW WITH SEVERAL SMALLER SCALE DISTURBANCES RESULTING IN A FEW TO SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE REST OF THE PERIOD. THEY WILL REMAIN DIFFICULT TO TIME UNTIL WE GET CLOSER TO THE WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 141 AM EDT MON JUN 17 2013 AN UPPER LEVEL DISTURBANCE WILL PRODUCE SHOWERS FOR KIWD AND POSSIBLY KSAW OVERNIGHT. LIFR CLOUD DECK HAS ALREADY FORMED AT KCMX AND IT LOOKS LIKE IT/S BEGINNING TO FORM AT KSAW IN UPSLOPE NE FLOW SO WILL INCLUDE LIFR CLOUDS IN AT BOTH SITES FOR THE OVERNIGHT. BELIEVE IFR TO LIFR CLOUD DECK WILL ALSO FORM AT KIWD BY 10Z AS WINDS SHIFT TO ONSHORE NE DIRECTION. LOW CLOUDS WILL GRADUALLY LIFT BY LATE MON MORNING BRINGING VFR CONDITIONS TO ALL TAF SITES. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 411 PM EDT SUN JUN 16 2013 WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. A TROUGH WILL DROP SOUTH ACROSS LAKE SUPERIOR THIS EVENING...LEADING TO WINDS SHIFTING TO THE NORTH TONIGHT. AS THE TROUGH CONTINUES SOUTHEAST ON MONDAY...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES AND REMAIN THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA FROM THE NORTHWEST FOR THURSDAY. THERE IS A POCKET OF FOG OVER EASTERN LAKE SUPERIOR /NEAR AND EAST OF GRAND MARAIS MI/ THAT HAS BEEN DIMINISHING AND MOVING AROUND TODAY. WOULD EXPECT THE DRY AIR TO CONTINUE TO EAT AWAY AT IT THIS EVENING...BUT THERE IS SOME CONCERN IT COULD EXPAND WITH RAIN OCCURRING OVER CENTRAL LAKE SUPERIOR THIS AFTERNOON/EVENING AND LINGER THROUGH THE NIGHT. IF FOG DOES LINGER TONIGHT...IT WILL CLEAR OUT MON MORNING AS MUCH DRIER AIR SURGES S INTO THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...KF AVIATION...07/JV MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
441 AM EDT MON JUN 17 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 411 PM EDT SUN JUN 16 2013 THE MAIN CONCERN FOR THE SHORT TERM FORECAST WILL BE THE ONGOING SHOWERS AND THUNDERSTORMS AND ADDITIONAL SHOWERS WITH THE TROUGH DROPPING SOUTH ACROSS THE AREA TONIGHT. INITIAL CONVECTION WAS OVER EASTERN UPPER MICHIGAN...WHERE THERE WAS INCREASED MOISTURE FROM THE FOG EARLIER TODAY AND CONVERGENCE FROM WEAK LAKE BREEZES. THESE INITIAL SHOWERS HAVE SHIFTED TO THE SOUTHEAST AND OUT OF THE CWA...BUT ARE SEEING SOME SHOWERS IN CENTRAL UPPER MICHIGAN ALONG THE LAKE SUPERIOR LAKE BREEZE. THESE SHOWERS HAVE BEEN LIMITED THUS FAR DUE TO THE DRY MID LEVEL AIR EVEN THOUGH THERE IS STRONG LOW LEVEL LAPSE RATES AND RAP ANALYZED SB CAPE VALUES OF 500-1000 J/KG. BUT WITH THE INVERTED V LOOK TO THE RAP SOUNDINGS...ML CAPES ARE STRUGGLING TO GET MUCH ABOVE 250-500 J/KG. THIS DRY AIR CAN ALSO BE SEEN IN THE DEWPOINTS /UPPER 40S/ AWAY FROM THE INFLUENCE OF THE GREAT LAKES. THERE HAVE EVEN BEEN SOME SIGNIFICANT JUMPS IN THE DEWPOINTS OVER THE EASTERN CWA...AS THE LAKE BREEZES HAVE MOVED IN AND OUT OF SOME OF THE SITES. FARTHER WEST...A PERSISTENT SHOWER/THUNDERSTORM CLUSTER MOVED INTO WESTERN GOGEBIC COUNTY OVER THE LAST HOUR AND DID PRODUCE SOME GUSTS UP TO 40KTS EVEN THOUGH THE CLUSTER IS DIMINISHING. THIS ISN/T TOO UNREASONABLE WITH CURRENT DCAPE VALUES OVER MUCH OF UPPER MICHIGAN AROUND 800-1000 J/KG AND THE INVERTED V SOUNDINGS. WOULD EXPECT THIS TO BE THE PRIMARY CONCERN FOR ANY SHOWERS/THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. FINALLY...ADDITIONAL SHOWERS/THUNDERSTORMS HAVE BEEN ONGOING JUST NORTHEAST OF LAKE SUPERIOR...DUE TO ONE PIECE OF SHEARED OFF UPPER LEVEL ENERGY DROPPING SOUTHEAST ALONG THE TROUGH. THESE SHOWERS WILL CONTINUE QUICKLY SOUTHEAST AS THE STORM MOTION IS AROUND 40KTS. THE AREA THAT WILL BRING THE BEST CHANCE FOR SHOWERS IS THE REMNANT SHORTWAVE FROM THE UPPER LOW THAT WAS IN CENTRAL SASKATCHEWAN YESTERDAY. THIS SHORTWAVE HAS STARTED TO MOVE TOWARDS THE CANADA/ND/MN BORDER AND HAS SPARKED SHOWERS AND THUNDERSTORMS ALONG THE SURFACE TROUGH WHERE THERE IS DEEPER MOISTURE. WITH THE STORM MOTION TO THE SOUTHEAST AROUND 30-35KTS AND THE TROUGH SLOWLY SAGGING SOUTHEAST...WOULD EXPECT THOSE SHOWERS TO MOVE SOUTHEAST ACROSS WESTERN/CENTRAL UPPER MICHIGAN LATE THIS AFTERNOON AND INTO THE EVENING HOURS. NOT ENTIRELY CONFIDENT ON THE EASTERN CWA...AS IT WILL DEPEND ON THE THUNDERSTORMS CURRENTLY MOVING SOUTHEAST FROM THUNDER BAY AND HOW FAR SOUTHEAST THEY WILL MAKE IT BEFORE DIMINISHING. WILL HAVE LOWER POPS THAN OVER THE WEST...BUT STILL IN THE LOW END CHANCE CATEGORY. AN EARLIER UPDATE COVERED THE TIMING WELL OVER THE WEST AND HAVE JUST MADE MINOR TWEAKS TO MATCH THE CURRENT CONDITIONS...WITH MOST AREAS IN THE HIGHER REACHES OF THE SCATTERED/CHANCE CATEGORY. THINK THERE IS A DECENT SHOT MOST LOCATIONS WILL SEE RAIN...BUT THE COVERAGE/TIMING WOULD BE BETTER REFLECTED IN THE SCATTERED WORDING. AS MENTIONED ABOVE...THE DRY AIR AND LIMITED INSTABILITY WILL BE THE MAIN LIMITING FACTORS TO THE THUNDERSTORMS AND THEIR SEVERE POTENTIAL. BEST THREAT WILL BE WEST-SOUTHWEST OF THE CWA WHERE THE 850-700/500MB LAPSE RATES ARE THE STEEPEST...BUT THERE COULD BE SOME STRONGER STORMS OVER THE SOUTHWEST THIRD OF THE CWA. HAIL POTENTIAL WILL BE LIMITED DUE TO THE LIMITED INSTABILITY AND TALL/SKINNY CAPE. AS MENTIONED ABOVE...GUSTY WINDS WILL BE THE BIGGEST THREAT OVER THE SW HALF OF THE CWA...AS THEY HAVE THE STEEPER MID LEVEL LAPSE RATES...COMBINED WITH THE DRY LOW LEVELS TO PRODUCE THE HIGHER DCAPE VALUES. THEN...AS THE SHORTWAVE TRACKS SOUTHEAST INTO NORTHWEST WISCONSIN TONIGHT AND THE REST OF NORTHERN WISCONSIN ON MONDAY MORNING...WOULD EXPECT SCATTERED SHOWERS TO CONTINUE THROUGH THE NIGHT OVER THE SOUTHWEST HALF OF THE CWA. THAT IS ALSO WHERE THE BEST 850-500MB Q-VECTOR CONV IS LOCATED EVEN THOUGH THE DEEPER MOISTURE IS OVER EASTERN UPPER MICHIGAN. HAVE SLOWLY DIMINISHED THE THUNDER THREAT OVERNIGHT AND INTO MONDAY MORNING TO BE OVER THE SOUTHERN PART OF THE CWA...WHERE THE BETTER FORCING IS LOCATED. WILL HOLD ON TO SOME LIGHT RAIN SHOWERS OVER NORTHERN UPPER MICHIGAN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING...AS LOW LEVEL CONVERGENCE INCREASES WITH THE WINDS SHIFTING TO THE NORTH-NORTHEAST. WITH DECENT MOISTURE BELOW 10KFT AS THAT CONVERGENCE OCCURS...THINKING THERE WILL BE ENOUGH TO PRODUCE SOME SHOWERS...ESPECIALLY OVER SOME OF THE HIGHER TERRAIN LOCATIONS OF NORTH CENTRAL UPPER MICHIGAN WHERE THE WINDS BECOME UPSLOPE FOR A PERIOD OF TIME. THE LARGER SCALE FORCING SHOULD DEPART THE SOUTHWEST AND SOUTH CENTRAL CWA AROUND DAYBREAK AND THEY WILL BE LEFT WITH ANY SHOWERS DROPPING SOUTH ALONG THE ENHANCED CONVERGENCE. BEHIND THE TROUGH...LOW CLOUDS SEEN IN CENTRAL ONTARIO/MANITOBA THIS MORNING WILL MOVE SOUTH ACROSS THE CWA LATE TONIGHT INTO TOMORROW MORNING. MODELS STRUGGLING WITH HOW LOW THE CLOUDS WILL BE...BUT EITHER WAY A CLOUDY START TO THE WORK WEEK IS EXPECTED. CANADIAN HIGH PRESSURE IS EXPECTED TO BUILD OVER THE AREA ON MONDAY AFTERNOON...BRINGING DRIER AIR AND SUBSIDENCE TO THE AREA IN THE AFTERNOON. THIS WILL PRODUCE DECREASING CLOUDS FROM NORTH TO SOUTH. HIGHS WILL BE MUCH COOLER TOMORROW...WITH 60S IN MOST LOCATIONS EXCEPT NEAR LAKE SUPERIOR WHERE NORTHERLY FLOW OFF THE LAKE WILL KEEP HIGHS IN THE UPPER 50S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 411 PM EDT SUN JUN 16 2013 THROUGH THE MIDDLE OF THE WEEK...NW FLOW WILL PREVAIL INTO THE UPPER GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE PLAINS AND A BROAD TROF OVER ERN NAMERICA. AS THE RIDGE SHIFTS TO THE MISSISSIPPI VALLEY/GREAT LAKES LATE WEEK...IT WILL LOOSE AMPLITUDE AS SHORTWAVE ENERGY EJECTING E FROM A TROF OVER THE NW CONUS BEGINS TO SUPPRESS THE RIDGE. THE NW FLOW EARLY ON WILL SUPPORT DRY WEATHER FOR UPPER MI. MOVING INTO THE LATE WEEK PERIOD...PATTERN SHOULD BECOME ACTIVE WITH DECENT PCPN PROSPECTS AS SHORTWAVES TRACK E ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...COOLEST WEATHER WILL OCCUR OVER THE NEXT DAY OR TWO BEHIND SHORTWAVE PASSING TONIGHT/MON. THEN...DESPITE NW FLOW...TEMPS THRU THE MIDWEEK PERIOD SHOULD BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE NORMAL SINCE ERN TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE ERN CONUS... RESULTING IN COOLER AIR STAYING E AND NE OF THE AREA. TEMPS LATE WEEK INTO THE WEEKEND WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID CONDITIONS. COULD BE UNCOMFORTABLY HUMID FOR A DAY OR TWO. BEGINNING MON NIGHT...A CHILLY NIGHT IS ON THE WAY AS HIGH PRES BUILDS INTO THE UPPER LAKES. WITH VERY DRY COLUMN (PRECIPITABLE WATER 30-50PCT OF NORMAL) AND WINDS DIMINISHING TO LIGHT/CALM...WILL CONTINUE TO FAVOR THE LOW END OF MODEL GUIDANCE FOR MIN TEMPS... ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE ARRIVING DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING CONDITIONS...THERE IS A GOOD POTENTIAL FOR SOME FROST IN THE USUAL COLDER AREAS. SOME OF THE TRADITIONAL COLD SPOTS COULD FALL TO NEAR FREEZING. RECORD LOW FOR NWS MQT SITE ON THE 18TH IS 38F. NOT OUT OF THE QUESTION THAT RECORD COULD BE TIED OR BROKEN. SFC HIGH PRES WILL BE SETTLED OVER THE UPPER LAKES TUE...PROVIDING A DRY/PLEASANT MID JUNE DAY WITH ABUNDANT SUNSHINE UNDER LINGERING VERY DRY COLUMN. LAKE BREEZES WILL BE THE RULE...KEEPING LAKESIDE LOCATIONS COOLER IN THE AFTN. GIVEN AVBL DRY AIR TO MIX DOWN...DWPTS SHOULD FALL TO THE MID 30S...POSSIBLY LOWER...IN THE INTERIOR... RESULTING IN MIN RH DOWN AROUND 25PCT. WOULDN`T BE SURPRISED TO SEE SOME LOCATIONS FALL TO AROUND 20PCT. FORTUNATELY...LIGHT WINDS WILL KEEP FIRE WX CONCERNS IN CHECK. MEDIUM RANGE GUIDANCE HAS AND STILL CONTINUES TO HINT THAT A SHORTWAVE WILL DROP SE...PASSING JUST N OF UPPER MI LATE WED/WED NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE GUIDANCE...IT STILL APPEARS THERE MAY BE SOME PCPN AT SOME POINT LATE WED/WED NIGHT. NOTHING MORE THAN SCHC/LOW CHC POPS ARE WARRANTED SINCE BETTER FORCING PASSES BY TO THE N AND SINCE COVERAGE WILL BE LOW IF PCPN DOES OCCUR. IF WAVE IS FASTER AND ARRIVES DURING PEAK HEATING WED...PCPN CHC WILL BE GREATER...BUT WOULD STILL NOT EXPECT ANYTHING MORE THAN SCT COVERAGE. ON THU...THERE IS THE POTENTIAL FOR SUBTLE BOUNDARY ASSOCIATED WITH THE SHORTWAVE PASSING BY THE AREA WED NIGHT TO HANG UP OVER/NEAR UPPER MI...AND THAT COULD BE THE FOCUS FOR SOME CONVECTION THU AFTN. MAINTAINED SCHC/LOW CHC POPS IN FCST. AS MENTIONED EARLIER...THE LATE WEEK PERIOD INTO THE WEEKEND COULD BECOME ACTIVE AS SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT LAKES...SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS TOWARD THE AREA. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST MID RANGE CHC POPS FOR SHRA/TSRA FOR PORTIONS OF FRI/SAT. SFC HIGH PRES MAY BEGIN TO BUILD S TOWARD THE UPPER LAKES SUN IN THE WAKE OF A SHORTWAVE SWINGING ACROSS HUDSON BAY/QUEBEC...SO PCPN CHANCES MAY DIMINISH ON SUN. OVERALL...THERE APPEARS TO BE DECENT POTENTIAL THAT MOST LOCATIONS WILL SEE SOME RAIN AT SOME POINT BTWN FRI AND SUN. && FOR THE EXTENDED... ISSUED AT 440 AM EDT MON JUN 17 2013 MODELS ARE STILL IN FAIRLY GOOD AGREEMENT IN THE PLACEMENT OF A MID/UPPER LEVEL RIDGE OVER THE PLAINS THROUGH THE DAY FRIDAY...WITH THE ASSOCIATED SURFACE HIGH PRESSURE DOMINATING THE UPPER GREAT LAKES REGION THROUGH SATURDAY. THIS WILL KEEP DRY WEATHER WITH PREDOMINATE LIGHT N/NERLY WINDS THROUGH THIS TIME PERIOD. SUNNY/PARTLY CLOUDY SKIES WILL KEEP TEMPERATURES FAIRLY STEADY /AT OR SLIGHTLY BELOW NORMAL/...WITH COOLEST TEMPERATURES NEAR LAKE SUPERIOR DUE TO NORTHERLY WINDS OFF THE LAKE. MODEL CONSENSUS ALSO SHOWS A SHORTWAVE DEVELOPING ON THE BACKSIDE OF THE RIDGE...HOWEVER DISAGREEMENTS COME IN TO PLAY ON THE PATH THIS SHORTWAVE WILL TAKE. GFS AND GEM SOLUTIONS HAVE THE SHORTWAVE DEVELOPING OVER THE PLAINS ON SATURDAY...THEN GETTING PUSHED TO THE SOUTHEAST UNDER THE INFLUENCE OF THE HIGH PRESSURE RIDGE AND DRY AIR ALREADY IN PLACE. THIS SOLUTION SEEMS THE MOST REASONABLE. ECMWF SOLUTION ON THE OTHER HAND CONTINUES TO BE MORE AGGRESSIVE WITH THIS SYSTEM...MOVING IT NORTHEAST ALONG THE BACKSIDE OF THE RIDGE AND REACHING THE UPPER GREAT LAKES BY SATURDAY AFTERNOON. WITH THE GFS/GEM...UPPER MI SHOULD REMAIN DRY. HOWEVER WILL KEEP SLIGHT CHANCES NEAR THE WI BORDER SATURDAY AFTERNOON...SPREADING FURTHER INLAND SATURDAY NIGHT AND SUNDAY TO ACCOUNT FOR ECMWF SOLUTION. WITH THE INCREASE IN CLOUD COVER ASSOCIATED WITH THIS SYSTEM...EXPECT LOW TEMPERATURES SAT NIGHT TO BE SLIGHTLY WARMER THAN PREVIOUS...BUT STILL HOVERING ON THE FREEZING LINE...SO SNOW COULD MIX IN WITH RAIN IN AFFECTED AREAS. PRECIP SHOULD DISSIPATE BY SUNDAY NIGHT AS SHORTWAVE MOVES TO THE SOUTHEAST AND HIGH PRESSURE BEGINS TO BUILD IN FROM CANADA THROUGH THE DAY MONDAY. .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 141 AM EDT MON JUN 17 2013 AN UPPER LEVEL DISTURBANCE WILL PRODUCE SHOWERS FOR KIWD AND POSSIBLY KSAW OVERNIGHT. LIFR CLOUD DECK HAS ALREADY FORMED AT KCMX AND IT LOOKS LIKE IT/S BEGINNING TO FORM AT KSAW IN UPSLOPE NE FLOW SO WILL INCLUDE LIFR CLOUDS IN AT BOTH SITES FOR THE OVERNIGHT. BELIEVE IFR TO LIFR CLOUD DECK WILL ALSO FORM AT KIWD BY 10Z AS WINDS SHIFT TO ONSHORE NE DIRECTION. LOW CLOUDS WILL GRADUALLY LIFT BY LATE MON MORNING BRINGING VFR CONDITIONS TO ALL TAF SITES. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 411 PM EDT SUN JUN 16 2013 WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. A TROUGH WILL DROP SOUTH ACROSS LAKE SUPERIOR THIS EVENING...LEADING TO WINDS SHIFTING TO THE NORTH TONIGHT. AS THE TROUGH CONTINUES SOUTHEAST ON MONDAY...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES AND REMAIN THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA FROM THE NORTHWEST FOR THURSDAY. THERE IS A POCKET OF FOG OVER EASTERN LAKE SUPERIOR /NEAR AND EAST OF GRAND MARAIS MI/ THAT HAS BEEN DIMINISHING AND MOVING AROUND TODAY. WOULD EXPECT THE DRY AIR TO CONTINUE TO EAT AWAY AT IT THIS EVENING...BUT THERE IS SOME CONCERN IT COULD EXPAND WITH RAIN OCCURRING OVER CENTRAL LAKE SUPERIOR THIS AFTERNOON/EVENING AND LINGER THROUGH THE NIGHT. IF FOG DOES LINGER TONIGHT...IT WILL CLEAR OUT MON MORNING AS MUCH DRIER AIR SURGES S INTO THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...ROLFSON EXTENDED... AVIATION...07/JV MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
148 AM EDT MON JUN 17 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 411 PM EDT SUN JUN 16 2013 THE MAIN CONCERN FOR THE SHORT TERM FORECAST WILL BE THE ONGOING SHOWERS AND THUNDERSTORMS AND ADDITIONAL SHOWERS WITH THE TROUGH DROPPING SOUTH ACROSS THE AREA TONIGHT. INITIAL CONVECTION WAS OVER EASTERN UPPER MICHIGAN...WHERE THERE WAS INCREASED MOISTURE FROM THE FOG EARLIER TODAY AND CONVERGENCE FROM WEAK LAKE BREEZES. THESE INITIAL SHOWERS HAVE SHIFTED TO THE SOUTHEAST AND OUT OF THE CWA...BUT ARE SEEING SOME SHOWERS IN CENTRAL UPPER MICHIGAN ALONG THE LAKE SUPERIOR LAKE BREEZE. THESE SHOWERS HAVE BEEN LIMITED THUS FAR DUE TO THE DRY MID LEVEL AIR EVEN THOUGH THERE IS STRONG LOW LEVEL LAPSE RATES AND RAP ANALYZED SB CAPE VALUES OF 500-1000 J/KG. BUT WITH THE INVERTED V LOOK TO THE RAP SOUNDINGS...ML CAPES ARE STRUGGLING TO GET MUCH ABOVE 250-500 J/KG. THIS DRY AIR CAN ALSO BE SEEN IN THE DEWPOINTS /UPPER 40S/ AWAY FROM THE INFLUENCE OF THE GREAT LAKES. THERE HAVE EVEN BEEN SOME SIGNIFICANT JUMPS IN THE DEWPOINTS OVER THE EASTERN CWA...AS THE LAKE BREEZES HAVE MOVED IN AND OUT OF SOME OF THE SITES. FARTHER WEST...A PERSISTENT SHOWER/THUNDERSTORM CLUSTER MOVED INTO WESTERN GOGEBIC COUNTY OVER THE LAST HOUR AND DID PRODUCE SOME GUSTS UP TO 40KTS EVEN THOUGH THE CLUSTER IS DIMINISHING. THIS ISN/T TOO UNREASONABLE WITH CURRENT DCAPE VALUES OVER MUCH OF UPPER MICHIGAN AROUND 800-1000 J/KG AND THE INVERTED V SOUNDINGS. WOULD EXPECT THIS TO BE THE PRIMARY CONCERN FOR ANY SHOWERS/THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. FINALLY...ADDITIONAL SHOWERS/THUNDERSTORMS HAVE BEEN ONGOING JUST NORTHEAST OF LAKE SUPERIOR...DUE TO ONE PIECE OF SHEARED OFF UPPER LEVEL ENERGY DROPPING SOUTHEAST ALONG THE TROUGH. THESE SHOWERS WILL CONTINUE QUICKLY SOUTHEAST AS THE STORM MOTION IS AROUND 40KTS. THE AREA THAT WILL BRING THE BEST CHANCE FOR SHOWERS IS THE REMNANT SHORTWAVE FROM THE UPPER LOW THAT WAS IN CENTRAL SASKATCHEWAN YESTERDAY. THIS SHORTWAVE HAS STARTED TO MOVE TOWARDS THE CANADA/ND/MN BORDER AND HAS SPARKED SHOWERS AND THUNDERSTORMS ALONG THE SURFACE TROUGH WHERE THERE IS DEEPER MOISTURE. WITH THE STORM MOTION TO THE SOUTHEAST AROUND 30-35KTS AND THE TROUGH SLOWLY SAGGING SOUTHEAST...WOULD EXPECT THOSE SHOWERS TO MOVE SOUTHEAST ACROSS WESTERN/CENTRAL UPPER MICHIGAN LATE THIS AFTERNOON AND INTO THE EVENING HOURS. NOT ENTIRELY CONFIDENT ON THE EASTERN CWA...AS IT WILL DEPEND ON THE THUNDERSTORMS CURRENTLY MOVING SOUTHEAST FROM THUNDER BAY AND HOW FAR SOUTHEAST THEY WILL MAKE IT BEFORE DIMINISHING. WILL HAVE LOWER POPS THAN OVER THE WEST...BUT STILL IN THE LOW END CHANCE CATEGORY. AN EARLIER UPDATE COVERED THE TIMING WELL OVER THE WEST AND HAVE JUST MADE MINOR TWEAKS TO MATCH THE CURRENT CONDITIONS...WITH MOST AREAS IN THE HIGHER REACHES OF THE SCATTERED/CHANCE CATEGORY. THINK THERE IS A DECENT SHOT MOST LOCATIONS WILL SEE RAIN...BUT THE COVERAGE/TIMING WOULD BE BETTER REFLECTED IN THE SCATTERED WORDING. AS MENTIONED ABOVE...THE DRY AIR AND LIMITED INSTABILITY WILL BE THE MAIN LIMITING FACTORS TO THE THUNDERSTORMS AND THEIR SEVERE POTENTIAL. BEST THREAT WILL BE WEST-SOUTHWEST OF THE CWA WHERE THE 850-700/500MB LAPSE RATES ARE THE STEEPEST...BUT THERE COULD BE SOME STRONGER STORMS OVER THE SOUTHWEST THIRD OF THE CWA. HAIL POTENTIAL WILL BE LIMITED DUE TO THE LIMITED INSTABILITY AND TALL/SKINNY CAPE. AS MENTIONED ABOVE...GUSTY WINDS WILL BE THE BIGGEST THREAT OVER THE SW HALF OF THE CWA...AS THEY HAVE THE STEEPER MID LEVEL LAPSE RATES...COMBINED WITH THE DRY LOW LEVELS TO PRODUCE THE HIGHER DCAPE VALUES. THEN...AS THE SHORTWAVE TRACKS SOUTHEAST INTO NORTHWEST WISCONSIN TONIGHT AND THE REST OF NORTHERN WISCONSIN ON MONDAY MORNING...WOULD EXPECT SCATTERED SHOWERS TO CONTINUE THROUGH THE NIGHT OVER THE SOUTHWEST HALF OF THE CWA. THAT IS ALSO WHERE THE BEST 850-500MB Q-VECTOR CONV IS LOCATED EVEN THOUGH THE DEEPER MOISTURE IS OVER EASTERN UPPER MICHIGAN. HAVE SLOWLY DIMINISHED THE THUNDER THREAT OVERNIGHT AND INTO MONDAY MORNING TO BE OVER THE SOUTHERN PART OF THE CWA...WHERE THE BETTER FORCING IS LOCATED. WILL HOLD ON TO SOME LIGHT RAIN SHOWERS OVER NORTHERN UPPER MICHIGAN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING...AS LOW LEVEL CONVERGENCE INCREASES WITH THE WINDS SHIFTING TO THE NORTH-NORTHEAST. WITH DECENT MOISTURE BELOW 10KFT AS THAT CONVERGENCE OCCURS...THINKING THERE WILL BE ENOUGH TO PRODUCE SOME SHOWERS...ESPECIALLY OVER SOME OF THE HIGHER TERRAIN LOCATIONS OF NORTH CENTRAL UPPER MICHIGAN WHERE THE WINDS BECOME UPSLOPE FOR A PERIOD OF TIME. THE LARGER SCALE FORCING SHOULD DEPART THE SOUTHWEST AND SOUTH CENTRAL CWA AROUND DAYBREAK AND THEY WILL BE LEFT WITH ANY SHOWERS DROPPING SOUTH ALONG THE ENHANCED CONVERGENCE. BEHIND THE TROUGH...LOW CLOUDS SEEN IN CENTRAL ONTARIO/MANITOBA THIS MORNING WILL MOVE SOUTH ACROSS THE CWA LATE TONIGHT INTO TOMORROW MORNING. MODELS STRUGGLING WITH HOW LOW THE CLOUDS WILL BE...BUT EITHER WAY A CLOUDY START TO THE WORK WEEK IS EXPECTED. CANADIAN HIGH PRESSURE IS EXPECTED TO BUILD OVER THE AREA ON MONDAY AFTERNOON...BRINGING DRIER AIR AND SUBSIDENCE TO THE AREA IN THE AFTERNOON. THIS WILL PRODUCE DECREASING CLOUDS FROM NORTH TO SOUTH. HIGHS WILL BE MUCH COOLER TOMORROW...WITH 60S IN MOST LOCATIONS EXCEPT NEAR LAKE SUPERIOR WHERE NORTHERLY FLOW OFF THE LAKE WILL KEEP HIGHS IN THE UPPER 50S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 411 PM EDT SUN JUN 16 2013 THROUGH THE MIDDLE OF THE WEEK...NW FLOW WILL PREVAIL INTO THE UPPER GREAT LAKES BTWN A RIDGE DRIFTING FROM THE ROCKIES TO THE PLAINS AND A BROAD TROF OVER ERN NAMERICA. AS THE RIDGE SHIFTS TO THE MISSISSIPPI VALLEY/GREAT LAKES LATE WEEK...IT WILL LOOSE AMPLITUDE AS SHORTWAVE ENERGY EJECTING E FROM A TROF OVER THE NW CONUS BEGINS TO SUPPRESS THE RIDGE. THE NW FLOW EARLY ON WILL SUPPORT DRY WEATHER FOR UPPER MI. MOVING INTO THE LATE WEEK PERIOD...PATTERN SHOULD BECOME ACTIVE WITH DECENT PCPN PROSPECTS AS SHORTWAVES TRACK E ACROSS THE NRN PLAINS TO THE GREAT LAKES. AS FOR TEMPS...COOLEST WEATHER WILL OCCUR OVER THE NEXT DAY OR TWO BEHIND SHORTWAVE PASSING TONIGHT/MON. THEN...DESPITE NW FLOW...TEMPS THRU THE MIDWEEK PERIOD SHOULD BE CLOSE TO NORMAL OR EVEN A LITTLE ABOVE NORMAL SINCE ERN TROF WILL NOT HAVE SIGNIFICANT AMPLITUDE INTO THE ERN CONUS... RESULTING IN COOLER AIR STAYING E AND NE OF THE AREA. TEMPS LATE WEEK INTO THE WEEKEND WILL BE ABOVE NORMAL WITH WARMER/MORE HUMID CONDITIONS. COULD BE UNCOMFORTABLY HUMID FOR A DAY OR TWO. BEGINNING MON NIGHT...A CHILLY NIGHT IS ON THE WAY AS HIGH PRES BUILDS INTO THE UPPER LAKES. WITH VERY DRY COLUMN (PRECIPITABLE WATER 30-50PCT OF NORMAL) AND WINDS DIMINISHING TO LIGHT/CALM...WILL CONTINUE TO FAVOR THE LOW END OF MODEL GUIDANCE FOR MIN TEMPS... ESPECIALLY OVER THE W WHERE SFC HIGH PRES CENTER WILL BE ARRIVING DURING THE NIGHT. WITH IDEAL RADIATIONAL COOLING CONDITIONS...THERE IS A GOOD POTENTIAL FOR SOME FROST IN THE USUAL COLDER AREAS. SOME OF THE TRADITIONAL COLD SPOTS COULD FALL TO NEAR FREEZING. RECORD LOW FOR NWS MQT SITE ON THE 18TH IS 38F. NOT OUT OF THE QUESTION THAT RECORD COULD BE TIED OR BROKEN. SFC HIGH PRES WILL BE SETTLED OVER THE UPPER LAKES TUE...PROVIDING A DRY/PLEASANT MID JUNE DAY WITH ABUNDANT SUNSHINE UNDER LINGERING VERY DRY COLUMN. LAKE BREEZES WILL BE THE RULE...KEEPING LAKESIDE LOCATIONS COOLER IN THE AFTN. GIVEN AVBL DRY AIR TO MIX DOWN...DWPTS SHOULD FALL TO THE MID 30S...POSSIBLY LOWER...IN THE INTERIOR... RESULTING IN MIN RH DOWN AROUND 25PCT. WOULDN`T BE SURPRISED TO SEE SOME LOCATIONS FALL TO AROUND 20PCT. FORTUNATELY...LIGHT WINDS WILL KEEP FIRE WX CONCERNS IN CHECK. MEDIUM RANGE GUIDANCE HAS AND STILL CONTINUES TO HINT THAT A SHORTWAVE WILL DROP SE...PASSING JUST N OF UPPER MI LATE WED/WED NIGHT. GIVEN THE FAIRLY CONSISTENT SIGNAL FROM ALL MEDIUM RANGE GUIDANCE...IT STILL APPEARS THERE MAY BE SOME PCPN AT SOME POINT LATE WED/WED NIGHT. NOTHING MORE THAN SCHC/LOW CHC POPS ARE WARRANTED SINCE BETTER FORCING PASSES BY TO THE N AND SINCE COVERAGE WILL BE LOW IF PCPN DOES OCCUR. IF WAVE IS FASTER AND ARRIVES DURING PEAK HEATING WED...PCPN CHC WILL BE GREATER...BUT WOULD STILL NOT EXPECT ANYTHING MORE THAN SCT COVERAGE. ON THU...THERE IS THE POTENTIAL FOR SUBTLE BOUNDARY ASSOCIATED WITH THE SHORTWAVE PASSING BY THE AREA WED NIGHT TO HANG UP OVER/NEAR UPPER MI...AND THAT COULD BE THE FOCUS FOR SOME CONVECTION THU AFTN. MAINTAINED SCHC/LOW CHC POPS IN FCST. AS MENTIONED EARLIER...THE LATE WEEK PERIOD INTO THE WEEKEND COULD BECOME ACTIVE AS SHORTWAVES TRACK ACROSS THE NRN CONUS TO THE GREAT LAKES...SUPPRESSING THE RIDGE THAT WAS SHIFTING ACROSS THE PLAINS TOWARD THE AREA. SIGNAL LOOKS STRONG ENOUGH TO WARRANT AT LEAST MID RANGE CHC POPS FOR SHRA/TSRA FOR PORTIONS OF FRI/SAT. SFC HIGH PRES MAY BEGIN TO BUILD S TOWARD THE UPPER LAKES SUN IN THE WAKE OF A SHORTWAVE SWINGING ACROSS HUDSON BAY/QUEBEC...SO PCPN CHANCES MAY DIMINISH ON SUN. OVERALL...THERE APPEARS TO BE DECENT POTENTIAL THAT MOST LOCATIONS WILL SEE SOME RAIN AT SOME POINT BTWN FRI AND SUN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 141 AM EDT MON JUN 17 2013 AN UPPER LEVEL DISTURBANCE WILL PRODUCE SHOWERS FOR KIWD AND POSSIBLY KSAW OVERNIGHT. LIFR CLOUD DECK HAS ALREADY FORMED AT KCMX AND IT LOOKS LIKE IT/S BEGINNING TO FORM AT KSAW IN UPSLOPE NE FLOW SO WILL INCLUDE LIFR CLOUDS IN AT BOTH SITES FOR THE OVERNIGHT. BELIEVE IFR TO LIFR CLOUD DECK WILL ALSO FORM AT KIWD BY 10Z AS WINDS SHIFT TO ONSHORE NE DIRECTION. LOW CLOUDS WILL GRADUALLY LIFT BY LATE MON MORNING BRINGING VFR CONDITIONS TO ALL TAF SITES. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 411 PM EDT SUN JUN 16 2013 WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. A TROUGH WILL DROP SOUTH ACROSS LAKE SUPERIOR THIS EVENING...LEADING TO WINDS SHIFTING TO THE NORTH TONIGHT. AS THE TROUGH CONTINUES SOUTHEAST ON MONDAY...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES AND REMAIN THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA FROM THE NORTHWEST FOR THURSDAY. THERE IS A POCKET OF FOG OVER EASTERN LAKE SUPERIOR /NEAR AND EAST OF GRAND MARAIS MI/ THAT HAS BEEN DIMINISHING AND MOVING AROUND TODAY. WOULD EXPECT THE DRY AIR TO CONTINUE TO EAT AWAY AT IT THIS EVENING...BUT THERE IS SOME CONCERN IT COULD EXPAND WITH RAIN OCCURRING OVER CENTRAL LAKE SUPERIOR THIS AFTERNOON/EVENING AND LINGER THROUGH THE NIGHT. IF FOG DOES LINGER TONIGHT...IT WILL CLEAR OUT MON MORNING AS MUCH DRIER AIR SURGES S INTO THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...SRF LONG TERM...ROLFSON AVIATION...07/JV MARINE...SRF
AREA FORECAST DISCUSSION
NWS JACKSON MS
431 PM CDT MON JUN 17 2013 .DISCUSSION... THERE HAVE BEEN TWO AREAS OF FOCUS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON. A COMPLEX OF STORMS THAT DEVELOPED EARLY THIS MORNING OVER NORTH CENTRAL MS INDUCED A STRONG OUTFLOW BOUNDARY THAT WORKED ITS WAY SOUTHWARD TO JUST ABOUT THE I-20 CORRIDOR IN CENTRAL/EASTERN MS. MORNING RUNS OF THE HRRR WERE CORRECT IN SHOWING TSTM DEVELOPMENT ALONG THE BOUNDARY IN CENTRAL MS...AND RELATIVELY STRONG LOW/MID LEVEL FLOW IS NOW FORCING THE BOUNDARY TO LIFT OUT AHEAD OF AN UPSTREAM CONVECTIVE COMPLEX. THE UPSTREAM CONVECTIVE COMPLEX MANAGED TO INITIATE NEW SHOWER/TSTM DEVELOPMENT AS IT CROSS THE ARKLATEX...BUT WHAT WAS A SOLID LINE OF SHOWERS/TSTM DEGENERATED INTO A BROKEN LINE OF SHOWERS AS IT MOVED INTO AND AREA OF NEGATIVE LOW LEVEL THETAE ADVECTION AND WESTERLY LOW LEVEL FLOW ALONG THE MS RIVER. AS THE RESIDUAL BOUNDARY MOVES FARTHER EAST...THE ENVIRONMENT MAY BE MORE SUPPORTIVE OF A FEW STORMS OVER CENTRL MS THIS EVENING. FAST WESTERLY FLOW WILL SEND MORE UPPER LEVEL PERTURBATIONS ACROSS THE ARKLAMISS FOR THE NEXT COUPLE OF DAYS. LOW LEVEL MOISTURE TRANSPORT AND CONVERGENCE WILL INCREASE LATER TONIGHT INTO TUESDAY AND PERHAPS TUESDAY EVENING. THIS SHOULD BE THE MOST ACTIVE CONVECTIVE PERIOD AND HAVE GENERALLY ACCEPTED HIGH MAV MOS GUIDANCE POPS...BUT INCREASED POPS SOME OVER SOUTHERN PORTIONS OF THE AREA TUESDAY INTO TUESDAY NIGHT GIVEN SOUTHWARD TRENDS IN GUIDANCE QPF FIELDS. AS DISCUSSED IN PREVIOUS DISCUSSIONS...TRYING TO PINPOINT SPECIFIC CONVECTIVE SYSTEM PASSES ACROSS THE ARKLAMISS WILL BE DIFFICULT IN THIS PATTERN GIVEN LITTLE HELP FROM EXPLICIT HIGH-RES GUIDANCE. WILL THERE KEEP THE FORECAST MORE GENERAL WITH THE IDEA THAT CONVECTION WILL INCREASE AGAIN LATER TONIGHT INTO TUESDAY MORNING. THE BETTER DAYTIME HEATING MAY TAKE PLACE ACROSS SOUTHERN PORTIONS OF THE ARKLAMISS TUESDAY...BUT THERE WILL BE SOME RISK FOR STRONG TO SEVERE STORMS FOR MOST OF THE FORECAST AREA. /EC/ WEDNESDAY THROUGH NEXT MONDAY...MODELS HAVE TRENDED A LITTLE DRIER FOR WEDNESDAY INTO THURSDAY AND POPS HAVE TRENDED LOWER. AN UPPER RIDGE WILL BUILD EAST INTO THE FORECAST AREA FRIDAY INTO THE WEEKEND. CHANCES FOR MAINLY AFTERNOON AND EARLY EVENING SHOWERS AND STORMS WILL REMAIN OVER PARTS OF THE FORECAST AREA DURING THIS TIME AND INTO NEXT MONDAY. CONVECTION FRIDAY THROUGH MONDAY IS EXPECTED TO BE MORE DIURNALLY DRIVEN AND ISOLATED TO SCATTERED IN NATURE COMPARED TO THE MORE ORGANIZED CONVECTION SEEN EARLIER IN THE WORK WEEK. OTHERWISE...WARM AND VERY HUMID CONDITIONS WILL PERSIST THROUGH THE ENTIRE PERIOD. HIGHS EACH AFTERNOON WILL RANGE IN THE LOW TO MIDDLE 90S. GUIDANCE SUGGESTED AS THE RIDGE BUILT IN FRIDAY...HIGHS COULD RANGE FROM 95-97. GIVEN EXPECTED WET GROUND CONDITIONS DURING THIS TIME...FELT THESE WERE TOO HIGH. THEREFORE I KNOCKED OFF 2-3 DEGREES AND NOW HAVE HIGHS RANGING FROM 92-94 ON FRIDAY. ELSEWHERE THROUGH THE PERIOD...BOTH GUIDANCE HIGH AND LOW TEMPERATURES LOOKED REASONABLE. /19/EC/ && .AVIATION... FOR TONIGHT...THERE LOOKS TO BE SOME LINGERING STORM CHANCES OVERNIGHT AND SOME RISK FOR SOME MVFR CONDITIONS FOR THE AREAS THAT RECEIVED PRECIP. && .PRELIMINARY POINT TEMPS/POPS... JACKSON 71 87 68 93 / 52 69 38 19 MERIDIAN 71 87 67 92 / 52 73 49 15 VICKSBURG 73 87 66 92 / 53 57 29 21 HATTIESBURG 73 91 71 94 / 29 56 41 40 NATCHEZ 72 87 70 91 / 45 61 29 42 GREENVILLE 72 87 67 92 / 71 48 15 12 GREENWOOD 71 86 66 91 / 73 50 19 12 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON MS
1056 AM CDT MON JUN 17 2013 .UPDATE... OVERALL..,ONLY MINOR ADJUSTMENTS WERE MADE IN THIS FORECAST UPDATE. THERE ARE TWO AREAS OF FOCUS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON. A COMPLEX OF STORMS THAT DEVELOPED EARLY THIS MORNING OVER NORTH CENTRAL MS HAS STABILIZED AREAS ALONG THE HIGHWAY 82 CORRIDOR. THE LATEST HRRR SUGGESTS THAT FUTURE CONVECTION WILL DEVELOP ALONG THE DIFFERENTIAL HEATING/OUTFLOW BOUNDARY LEFT FROM THIS COMPLEX OVER AREAS NORTH OF I-20. THE OTHER FEATURE OF CONCERN IS THE DECAYING UPSTREAM CONVECTIVE COMPLEX CURRENTLY CROSSING THE ARKLATEX. HIGH RES GUIDANCE SUGGEST FURTHER DECAY OF COMPLEX WITH A RESIDUAL BOUNDARY HELPING TO INITIATE STORMS LATER THIS AFTERNOON INTO THE EVENING. LIMITING FACTORS HOWEVER IN ENVIRONMENT AHEAD OF THE COMPLEX ARE THE NEGATIVE LOW-LEVEL THETAE ADVECTION INTO SOUTHERN PORTIONS OF THE ARKLAMISS...AND RELATIVE WESTERLY FLOW AHEAD OF THE BOUNDARY THAT IS LIMITING LOW LEVEL CONVERGENCE. WITH THIS IN MIND...STILL EXPECT GREATEST AFTERNOON CONVECTIVE POTENTIAL FOR AREAS ALONG AND NORTH OF THE I-20 CORRIDOR AND THE GOING FORECAST HAS A GOOD HANDLE ON THE SCENARIO. THE UPDATED AVIATION DISCUSSION IS BELOW. /EC/ && .PREV DISCUSSION... /ISSUED 326 AM CDT MON JUN 17 2013/ SHORT TERM...CHALLENGING CONVECTIVE FORECAST TODAY AS TIMING SPECIFICS ARE VERY DIFFICULT DUE TO POOR REPRESENTATION OF THE CURRENT S/WV`S AND MCV FEATURES IN THE MODEL DATA. STILL...THE PATTERN WILL SUPPORT MULTIPLE S/WV FEATURES THROUGH TUE NIGHT AND BRING SEVERAL OPPORTUNITIES FOR SHRA/TSRA DURING THE NEXT 48 HRS. YESTERDAY OFFERED GREATER STORM/PRECIP COVERAGE THAN EXPECTED AND WAS LIKELY THE KICKOFF DAY FOR THIS UPCOMING WETTER PERIOD. ATMOSPHERIC MOISTURE SHOWED A MARKED INCREASE FROM SUNDAY MORNING TO THE AFTERNOON AS PWS REACHED 2 IN. LOOK FOR THIS MORE MOIST AIRMASS TO HANG AROUND WITH PWS RANGING FROM 1.75-2.0 INCHES. THIS WILL COMBINE WITH MULTIPLE DISTURBANCES TRAVERSING THE REGION TO INSTIGATE NUMEROUS SHOWERS AND STORMS. THE FIRST MCV JUST PUSHED INTO AL AND WAS GENERATED BY THE AFTERNOON STORMS OVER THE WESTERN PART OF THE CWA. EARLY THIS MORNING...A MCV IS PUSHING EAST ACROSS CENTRAL AR AND WILL LIKELY AID IN PRECIP ACTIVITY THIS MORNING/AFTERNOON. THERE IS ALSO A MUCH LARGER DISTURBANCE PUSHING ACROSS OK AND THIS WILL TOO HELP SUPPORT CONVECTION LATER IN THE AFTERNOON/EVE ESPECIALLY ACROSS THE W/NW AREAS. IF THAT WASN`T ENOUGH...ADDITIONAL DISTURBANCES ARE PROGGED TO CONTINUE IN THE PERTURBED FLOW AND SUPPORT ADDITIONAL CONVECTION THROUGH TUE. AT THIS TIME...WILL CONTINUE TO BE GENERAL WITH TIMING DUE TO THE UNCERTAINTY WITH HOW EACH FEATURE WILL EVOLVE AND FOLLOW CLOSE TO THE HIGHER GUIDANCE POPS. FOR TODAY...I CURRENTLY HAVE THE BEST PRECIP CHANCES FOR THE AFTERNOON...BUT THIS MAY HAVE TO BE REVISITED BASED ON HOW STORM TRENDS THIS MORNING GO. TODAY SEEMS TO HAVE A POTENTIAL FOR STRONG STORMS ALONG WITH A FEW SEVERE STORMS MIXED IN. THE REASON IS THAT SOME WARMER SFC TEMPS MAY BE REALIZED AS HIGHS PEAK AROUND 90 WHICH COULD RESULT IN NEAR 3000 J/KG OF SBCAPE. THERE WILL ALSO BE SOME COOLER MID LEVEL TEMPS ALONG WITH SOME STRONGER FLOW (25-30KTS) AT 500MB WHICH SHOULD HELP SUPPORT A FEW VIGOROUS UPDRAFTS. DUE TO THIS...WILL MENTION THIS POTENTIAL IN THE HWO/GRAPHICS. THE MAIN THREAT WILL BE FROM GUSTY WINDS 50-60 MPH AND SMALL HAIL. YESTERDAY...LIGHTNING WAS ALSO FREQUENT WITH THE STRONGER STORMS AND THAT MAY AGAIN BE THE CASE. /CME/ LONG TERM...WEDNESDAY THROUGH NEXT MONDAY...A RATHER ACTIVE PATTERN CONTINUES ACROSS THE FORECAST AREA AS NORTHWEST FLOW PERSISTS INTO AT LEAST THURSDAY...WHILE SUBTLE UPPER LEVEL DISTURBANCES IMPEDE UPON THE CWA ALONG A QUASI-STATIONARY SURFACE BOUNDARY. AN UPPER RIDGE WILL BUILD EAST INTO THE FORECAST AREA FRIDAY INTO THE WEEKEND. CHANCES FOR MAINLY AFTERNOON AND EARLY EVENING SHOWERS AND STORMS WILL REMAIN OVER PARTS OF THE FORECAST AREA DURING THIS TIME AND INTO NEXT MONDAY. CONVECTION FRIDAY THROUGH MONDAY IS EXPECTED TO BE MORE DIURNALLY DRIVEN AND ISOLATED TO SCATTERED IN NATURE COMPARED TO THE MORE ORGANIZED CONVECTION SEEN EARLIER IN THE WORK WEEK. OTHERWISE...WARM AND VERY HUMID CONDITIONS WILL PERSIST THROUGH THE ENTIRE PERIOD. HIGHS EACH AFTERNOON WILL RANGE IN THE LOW TO MIDDLE 90S. GUIDANCE SUGGESTED AS THE RIDGE BUILT IN FRIDAY...HIGHS COULD RANGE FROM 95-97. GIVEN EXPECTED WET GROUND CONDITIONS DURING THIS TIME...FELT THESE WERE TOO HIGH. THEREFORE I KNOCKED OFF 2-3 DEGREES AND NOW HAVE HIGHS RANGING FROM 92-94 ON FRIDAY. ELSEWHERE THROUGH THE PERIOD...BOTH GUIDANCE HIGH AND LOW TEMPERATURES LOOKED REASONABLE. /19/ && .AVIATION...CONDITIONS WILL GENERALLY BE VFR VFR TODAY...THE EXCEPTION BEING MVFR CIGS/VSBYS...LCLY IFR VSBYS...WHERE SHWRS/TSTMS OCCUR. AN AREA OF LATE MORNING SHWRS/TSTMS EXISTS OVER NRN/NERN ZONES DURING THE LATE MORNING/EARLY AFTERNOON. THE FOCUS WILL SHIFT TO SCT SHWRS/TSTMS FOR THE REMAINDER OF THE REGION DURING THE AFTERNOON. FOR TONIGHT...THERE LOOKS TO BE SOME LINGERING STORM CHANCES OVERNIGHT AND SOME RISK FOR SOME MVFR CONDITIONS FOR THE AREAS THAT RECEIVED PRECIP. /CME/03 && .PRELIMINARY POINT TEMPS/POPS... JACKSON 92 71 89 70 / 36 42 49 50 MERIDIAN 91 70 89 69 / 49 47 57 57 VICKSBURG 92 72 89 70 / 29 45 50 47 HATTIESBURG 92 72 91 72 / 36 23 36 31 NATCHEZ 90 71 89 70 / 26 25 37 32 GREENVILLE 91 73 87 70 / 51 67 66 40 GREENWOOD 90 71 88 69 / 54 66 68 41 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION
NWS BILLINGS MT
859 PM MDT TUE JUN 18 2013 .UPDATE... UPDATE TO FORECAST THIS EVENING. UPPER RIDGE OF HIGH PRESSURE MOVING SLOWLY EASTWARD ACROSS THE FORECAST AREA THIS EVENING AS AN UPPER TROUGH OF LOW PRESSURE MOVES ON TO THE PACIFIC WEST COAST. ISOLATED THUNDERSTORMS DID DEVELOP OVER THE HIGHER TERRAIN THIS AFTERNOON AND EVENING BUT DID NOT MOVE VERY FAR AWAY FROM THE MOUNTAINS DUE TO VERY LIGHT MID-LEVEL STEERING WINDS. A FEW STORMS DID PRODUCE HEAVY RAINFALL AS THEY WERE ABLE TO TAP INTO A SHALLOW MOIST BOUNDARY LAYER. BULK WIND SHEAR WAS NON-EXISTENT AND NO SEVRE WEATHER DEVELOPED. FOR TONIGHT...HAVE LOWERED POPS TO ISOLATED FOR THE REST OF THE EVENING WITH A DRY FORECAST AFTER 06Z. DID BUMP OVERNIGHT LOWS UP A FEW DEGREES ACROSS THE CENTRAL ZONES AS THERMAL RIDGE WILL REMAIN OVER THESE AREAS TONIGHT. REST OF THE FORECAST ON TRACK. RICHMOND && .SHORT TERM...VALID FOR WED AND THU... CONVECTION WAS OCCURRING OVER SOUTHERN PARTS OF THE AREA PER RADAR IMAGERY THIS AFTERNOON. LATEST RAP ANALYSIS SHOWED SURFACE CAPES OF 1500-2500 J/KG OVER SE MT. ELSEWHERE...CAPES WERE IN THE 700 TO 2000 J/KG RANGE...PRETTY VARIABLE ACROSS THE FORECAST AREA. SHEAR WAS GENERALLY WEAK...HOWEVER VALUES WERE 30 TO 35 KT OVER SE MT...SO BEST CHANCES OF ANY STRONG TO SEVERE STORMS WILL BE OVER THE SE. WILL CONTINUE TO MENTION SMALL HAIL/GUSTY WINDS ACROSS THE AREA DUE TO THE CAPES AND INVERTED-V SOUNDINGS. HAD POPS ACROSS THE AREA THIS EVENING...THEN ACTIVITY SHOULD DISSIPATE AFTER MIDNIGHT MDT WITH LOSS OF HEATING. JET ENERGY WILL ROTATE AROUND THE UPPER LOW OVER THE PACIFIC NW...CAUSING IT TO PROGRESS E WITH TIME. WILL HAVE INCREASING Q-VECTOR CONVERGENCE OVER THE AREA STARTING ON WED...AS SHORTWAVES CONTINUE MOVING INTO THE REGION. UPPER DIFLUENCE WILL CONTINUE TO CONTRIBUTE TO LIFT ON WED. BOTH THE GFS AND WRF HAD LARGE CAPES 2000-3000 J/KG OVER THE FAR EASTERN AND NORTHERN PARTS OF THE AREA WED AND WED EVENING...AS WELL AS INCREASING SHEAR OVER THE AREA FROM W TO E. HOWEVER...DRY AIR OVER THE FOUR CORNERS REGION THIS AFTERNOON WILL ADVECT N INTO THE FORECAST AREA ON WED...KEEPING THE E DRY THROUGH THE DAY. WILL KEEP A CHANCE OF THUNDERSTORMS OVER THE NW HALF OF THE REGION FROM KBIL N AND W...AND WILL CONTINUE TO MENTION POSSIBLE SEVERE OVER THE N. COLD FRONT MOVES THROUGH WED NIGHT BRINGING A CHANCE OF THUNDERSTORMS TO MOST OF THE AREA. UPPER LOW WILL ROTATE OVER ID THU AND THU NIGHT. CAPES WILL BE VERY LOW ON THU. HAD LOW POPS ACROSS THE AREA. A SECONDARY COLD FRONT WITH FRONTOGENESIS WILL MOVE THROUGH THE REGION THU NIGHT...BRINGING A BETTER CHANCE OF PRECIPITATION. WILL HAVE A WARM NIGHT TONIGHT AS 850 MB THERMAL RIDGE MOVES INTO THE AREA AND LOW-LEVEL JET STRENGTHENS OVER THE E. WED WILL BE HOT WITH 700 MB TEMPERATURES AROUND +14 DEGREES C AHEAD OF THE COLD FRONT. ARTHUR .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... PAC NW UPPER LOW WILL KICK SLOWLY THROUGH THE REGION FRI/SAT...AND ALL MODELS HAVE TRENDED SIMILARLY WITH REGARD TO STRENGTH AND TIMING OF THIS FEATURE. WITH CONFIDENCE HAVE RAISED POPS ACROSS THE REGION ON THESE DAYS. ACTIVITY IN THE WEST SHOULD BE NON- SEVERE THOUGH WITH LOW WET BULB TEMPS SOME SMALL HAIL IS POSSIBLE WITH ANY STRONGER CELLS. GFS SHOWS DEEPER MOISTURE AND INSTABILITY MAY SURGE FROM THE DAKOTAS INTO OUR EAST AHEAD OF THE UPPER LOW...SO CANNOT RULE OUT THE POTENTIAL FOR SEVERE STORMS IN OUR EAST ON THESE DAYS...ALONG WITH HEAVY RAIN. SYSTEM WILL EXIT TO OUR EAST EITHER SATURDAY NIGHT OR EARLY SUNDAY. TEMPS FRIDAY AND SATURDAY WILL COOL TO SLIGHTLY BELOW NORMAL. DRIER CONDITIONS SHOULD EMERGE BY SUNDAY IN OUR WEST...WITH A PERIOD OF DRY WX PERHAPS EXTENDING INTO MONDAY UNDER SHORTWAVE RIDGING. MODELS DIVERGE A BIT IN THE HANDLING OF THE PACIFIC FLOW HERE. WILL ADVERTISE A DRY PERIOD SUNDAY INTO MONDAY...THEN SLIGHT POPS MONDAY AFTERNOON THROUGH TUESDAY AS WE MAY BE IMPACTED BY PACIFIC SHORTWAVE ENERGY BY THEN. TEMPS SHOULD RETURN BACK TO A LITTLE ABOVE NORMAL BY DAYS 6/7. LOOKING FURTHER AHEAD...LATEST GFS/ECMWF SHOW STRONGER RIDGING WITH NEAR 590DAM HEIGHTS BY WED/THU OF NEXT WEEK. WILL NEED TO KEEP WATCH OF THIS TREND. JKL && .AVIATION... AN ISOLATED THUNDERSTORM MAY PERSIST UNTIL 06Z FROM NORTHERN WYOMING INTO SOUTHEAST MONTANA WITH LOCAL MVFR VISIBILITY IN HEAVY RAINFALL. OTHERWISE VFR CONDITIONS EXPECTED THROUGH MID DAY WEDNESDAY. ANOTHER ROUND OF ISOLATED TO SCATTERED THUNDERSTORMS IS EXPECTED WEDNESDAY AFTERNOON AND EVENING. WIND GUSTS WITH THESE STORMS WILL BE STRONG AT TIMES. CHAMBERS && .PRELIMINARY POINT TEMP/POPS... WED THU FRI SAT SUN MON TUE ----------------------------------------------------------- BIL 061/089 052/077 052/072 052/069 051/078 054/082 056/082 22/T 22/T 33/T 34/T 41/B 12/T 22/T LVM 051/084 043/072 041/069 042/067 046/079 046/082 049/081 33/T 23/T 33/T 34/T 40/B 02/T 22/T HDN 061/091 053/078 052/074 050/072 050/078 052/082 052/083 21/U 22/T 32/T 34/T 41/B 12/T 22/T MLS 061/096 058/081 055/076 056/076 055/080 056/083 057/083 21/N 22/T 44/T 34/T 43/T 22/T 22/T 4BQ 061/095 054/081 055/076 054/075 053/079 054/084 055/084 21/N 22/T 44/T 34/T 42/T 12/T 22/T BHK 057/090 057/080 054/076 055/074 054/076 054/080 057/082 21/N 22/T 36/T 54/T 43/T 22/T 22/T SHR 054/090 048/078 050/073 048/073 047/076 049/081 050/082 31/U 22/T 32/T 23/T 31/B 12/T 22/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
441 PM CDT MON JUN 17 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 440 PM CDT MON JUN 17 2013 THE MAIN CONCERN DURING THE NEXT 24 HOURS CONTINUES TO CENTER AROUND THE VERY TRICKY...AND CONSTANTLY-EVOLVING THUNDERSTORM CHANCES...OR LACK THEREOF IN THIS NORTHWEST FLOW PATTERN. ALTHOUGH AT LEAST A LOW-END RISK FOR SEVERE STORMS CONTINUES THIS EVENING/TONIGHT MAINLY WEST OF HIGHWAY 281...IT DOES NOT LOOK TO BE NEARLY AS WIDESPREAD/SIGNIFICANT AS THE SUNDAY EVENING EVENT. 20Z OBJECTIVE SURFACE ANALYSIS INDICATES A FAIRLY NON-DESCRIPT PATTERN ACROSS THE AREA...WITH THE MAIN SYNOPTIC-SCALE COLD FRONT NOTED WELL TO THE SOUTH ACROSS OK/NORTHWEST TX. IT HAS BEEN COMPLETELY RAIN/THUNDER-FREE THE ENTIRE DAY SO FAR CWA-WIDE. WITH THE MAIN SURFACE FRONT TO THE SOUTH...AND A MODEST 1018 MILLIBAR RIDGE AXIS CENTERED JUST NORTH OF THE CWA...BREEZES THIS AFTERNOON ARE GENERALLY SOME VARIATION OF NORTHERLY/EASTERLY AT NO MORE THAN 10 MPH. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA DEPICTS THE CONTINUATION OF WEST-NORTHWEST FLOW ALOFT OVER THE CENTRAL PLAINS...FLOWING OVER THE TOP OF A FAIRLY LOW-AMPLITUDE RIDGE EXTENDING NORTH-SOUTH THROUGH THE CENTRAL/SOUTHERN ROCKIES. THERE ARE GENERALLY THREE SHORTWAVE TROUGHS/RIPPLES OF NOTE ACROSS THE REGION...ONE DEPARTING EASTWARD ALONG THE KS/MO/OK BORDER AREA...ONE SLIDING SOUTHEAST ACROSS ND...AND THE OTHER A FAIRLY SUBTLE DISTURBANCE DRIFTING SOUTHEAST ACROSS NORTHWEST NEB...WHICH HAS HELPED TRIGGER SOME THUS-FAR NON-SEVERE THUNDERSTORMS STILL 50-100 MILES WEST- NORTHWEST OF THE CWA AT THIS HOUR. VISIBLE SATELLITE IMAGERY REVEALS NOTHING MORE THAN A SCATTERED FAIR WEATHER CUMULUS FIELD OVER MOST OF THE CWA...WITH A FEW THICKER MID-CLOUD AREAS DRIFTING INTO NORTHERN/WESTERN COUNTIES OUT AHEAD OF THE WESTERN NEBRASKA CONVECTION. HIGH TEMPS ARE GENERALLY ON TRACK TO TOP OUT SOMEWHERE IN THE 80S MOST ALL AREAS. LATE THIS AFTERNOON INTO TONIGHT...PINNING DOWN THE HOURLY DETAILS OF POPS/THUNDERSTORMS CONTINUES TO BE A CHALLENGE. REGARDING THE BIG PICTURE ALOFT BETWEEN NOW AND SUNRISE...THE VERY SUBTLE MID LEVEL DISTURBANCES ROTATING AROUND THE TOP OF THE RIDGE ACROSS THE WY/CO/NORTHWEST NEB AREA WILL CONTINUE TO DRIFT SOUTHEAST...WHILE THE SOMEWHAT MORE ORGANIZED DISTURBANCE NOW OVER ND WILL REACH THE NORTH CENTRAL IA BY SUNRISE. FOR THE FORECAST...HAVE CONSIDERED A VARIETY OF DETERMINISTIC AND HIGH-RES MODEL SOLUTIONS TONIGHT...WHICH INVARIABLY PAINT AT LEAST SLIGHTLY DIFFERENT PICTURES...BUT LEANING MAINLY TOWARD THE HRRR/4 KM-WRF SOLUTIONS WHICH SEEM TO HAVE A DECENT HANDLE ON THE ONGOING CONVECTION TO THE WEST. THROUGH 7PM...HAVE KEPT THE MAJORITY OF THE CWA POP- FREE...WITH ONLY SLIGHT CHANCES CREEPING INTO ABOUT THE NORTHWEST 1/3 OF THE CWA AS CONVECTION DEVELOPS OVERHEAD AND/OR DRIFTS IN FROM THE NORTHWEST. BETWEEN 00Z-04Z/7PM-11PM...SPREAD AT LEAST SLIGHT 20 PERCENT POPS INTO EVEN THE FAR SOUTHEAST COUNTIES...WHILE RAISING INTO THE 40-50 PERCENT HIGH-CHANCE RANGE ACROSS MUCH OF THE WEST. BY 00Z...LATEST RAP INDICATES AN ENVIRONMENT AT LEAST MARGINALLY SUPPORTIVE OF SEVERE WEATHER...WITH ROUGHLY 1500 J/KG OF 0-1KM CAPE MAINLY IN THE NORTHWEST 1/2 OF THE CWA...AND 30-40 KNOTS OF 0-6KM DEEP LAYER SHEAR. AS THE EVENING WEARS ON...INSTABILITY IS PROGGED TO DROP OFF SLOWLY...BUT LIKELY REMAIN HIGHEST IN KS ZONES. AFTER MIDNIGHT...CURRENT POPS MAY NOT BE NEARLY HIGH ENOUGH IF IN FACT A SEMI-ORGANIZED BATCH OF CONVECTION DEVELOPS OVERHEAD OR MOVES IN...BUT GIVEN INHERENT UNCERTAINTY HAVE CAPPED POPS AT NO MORE THAN 40-50 PERCENT FOR NOW. GENERALLY HAVE FOLLOWED SPC SREF SEVERE THUNDER PROBABILITIES BY CONTINUING A MENTION OF STRONG TO MARGINALLY SEVERE STORMS IN THE HAZARDOUS WEATHER OUTLOOK MAINLY WEST OF HIGHWAY 281...WITH AN EXPECTATION OF A BROKEN LINE OF CONVECTION DRIFTING IN. WORST-CASE SCENARIO WOULD SEEM TO BE A 60-70 MPH WIND EVENT IF STORMS CAN ORGANIZE INTO A COLD POOL...BUT IN THEORY THIS SEEMS FAIRLY UNLIKELY GIVEN THAT CONVECTION SHOULD LOSE INTENSITY AS IT HEADS EAST OUT OF WESTERN NEB/NORTHWEST KS...SO WILL ONLY HIGHLIGHT A MARGINALLY SEVERE THREAT AT THIS TIME. LATER IN THE NIGHT...THERE ARE SUGGESTIONS BY MODELS SUCH AS THE NAM THAT A MODEST RIBBON OF LOW-MID LEVEL THETA-E ADVECTION IN THE 850-700MB LAYER COULD SPARK A NEW ROUND OF ELEVATED CONVECTION MAINLY WITHIN THE NORTHEAST QUADRANT OF THE CWA IN CLOSEST PROXIMITY TO THE SOUTHEAST-DRIFTING DAKOTAS SHORTWAVE...AND THUS HAVE PUT POPS BACK INTO THESE NORTHEAST ZONES THROUGH THE NIGHT IN CASE THIS OCCURS. MADE LITTLE CHANGE TO LOW TEMPS...WITH NEARLY ALL AREAS SETTLING WITHIN A FEW DEGREES OF 60. ALSO...CANNOT COMPLETELY RULE OUT SOME LIGHT FOG TONIGHT...BUT NOT EXPECTING WIDESPREAD VISIBILITY RESTRICTIONS OF 1-2 MILES OR LESS THAT WOULD REQUIRE FORMAL INCLUSION IN THE FORECAST. TURNING TO THE TUESDAY DAYTIME PERIOD...UNCERTAINLY JUST KEEPS GROWING...WITH SOME MODELS CONTINUING TO PAINT DAYTIME MORNING CONVECTION POSSIBLY AS A CONTINUATION OF THE OVERNIGHT ACTIVITY...AND ESPECIALLY WITHIN THE NORTHEAST 1/2 OF THE CWA IN CLOSEST PROXIMITY TO THE SHORTWAVE TROUGH GLANCING BY TO THE EAST. HOWEVER...BASED ON VARIOUS FACTORS INCLUDING UNCERTAINTY/CONSISTENCY WITH PREVIOUS FORECAST AND LESS QPF IN PREVIOUS MODEL RUNS...HAVE OPTED TO GO AHEAD AND LEAVE THE MAJORITY OF THE DAYTIME HOURS RAIN/THUNDERSTORM-FREE FOR NOW...WHILE ACKNOWLEDING THAT THE NEXT FEW SHIFTS MAY HAVE TO INSERT SOME POST-SUNRISE POPS WITH LIMITED NOTICE. FOR EXAMPLE...THE PREVIOUS 12Z NAM WAS ESSENTIALLY DRY DURING THE DAY...BUT THE NEW 18Z RUN NOW HAS PLENTY OF DAYTIME CONVECTION...WHICH COULD EASILY BE OVERDONE PER THE 12Z 4KM WRF- NMM...WHICH FITS THE MORE COMMON CONCEPTUAL PICTURE OF LACK OF FORCING IN THE WAKE OF THE IA SHORTWAVE TROUGH THAT CONTINUES PASSING SOUTHEAST. THIS CONCEPTUAL PICTURE OF THIS PATTERN WOULD ALSO SUGGEST THE BEST AFTERNOON STORM CHANCES WOULD BE IN OUR WESTERN COUNTIES...AND THUS AT LEAST FOR NOW...THE ONLY OFFICIAL THUNDERSTORM CHANCES IN THE CWA TOMORROW ARE FROM 3-7PM IN WESTERN COUNTIES...WITH NO STRONG SIGNAL FOR SEVERE STORMS SHOULD THEY OCCUR. AS HAS BEEN THE CASE LATELY...BE PREPARED FOR SOME POTENTIALLY NOTABLE CHANGES TO THE TIMING/MAGNITUDE OF THESE STORM CHANCES...AS LOOKING EVEN BEYOND THE FIRST 12 HOURS IS PROVING DICEY...AND MORNING CONVECTION COULD BE A WILD CARD. TEMP-WISE TOMORROW...ASSUMING DAYTIME CONVECTION DOES NOT BLOSSOM AND CLOUD THINGS UP...EXPECT ANOTHER SEASONABLY WARM DAY AND NUDGED UP HIGHS SLIGHTLY...GETTING MOST PLACES BETWEEN 81-86 DEGREES. BREEZES WILL START OUT LIGHT BUT PICK UP TO 10-15 MPH FROM THE SOUTHEAST AS THE AFTERNOON WEARS ON WITH HIGHER GUSTS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 440 PM CDT MON JUN 17 2013 PRIMARY FORECAST CONCERNS THROUGH THE LONG TERM PERIOD REVOLVE AROUND PRECIPITATION CHANCES. THE START OF THE LONG TERM PERIOD TUESDAY EVENING/NIGHT SHOWS THE REGION REMAINING UNDER THE INFLUENCE OF WEAK/BROAD RIDGING IN THE UPPER LEVELS...BETWEEN AREAS OF LOW PRESSURE NEAR THE FAR NERN CONUS AND THE PAC NW COAST. EXPECTING THAT THERE WILL BE ACTIVITY ONGOING OVER THE HIGH PLAINS BY 00Z...WITH THE MAIN CONCERN BEING HOW FAR EAST/HOW MUCH OF THE CWA ENDS UP BEING AFFECTED. THIS ACTIVITY LOOKS TO TAKE ITS TIME SLIDING EAST...WITH LOW POPS IN PLACE THROUGH THE EARLY/MID EVENING HOURS. MODELS REMAIN IN DECENT AGREEMENT SHOWING THE WRN PORTIONS OF THE CWA SEEING THE BETTER CHANCES OF SEEING THUNDERSTORM...BUT ITS POSSIBLE NOT A WHOLE HECK OF A LOT WILL MAKE IT...SO THERE ISNT A BIG RAMP UP IN POPS DURING THE OVERNIGHT PERIOD. AS WE LOOK TOWARD WEDNESDAY AND INTO THURSDAY...PRECIPITATION CHANCES REMAIN IN THE FORECAST...BUT NOTHING IS CERTAINLY CLEAR CUT. MODELS ARE IN GOOD AGREEMENT SHOWING THAT ABOVE MENTIONED PAC NW UPPER LEVEL LOW PRESSURE SYSTEM SLIDING INLAND WEDNESDAY MORNING...BUT BY THURSDAY MORNING HAS ONLY MOVED INTO THE WA/ID/MT BORDER AREA. THE MAIN QUESTION LIES WITH THE TIMING/LOCATION OF PIECES OF ENERGY EJECTED OUT AHEAD OF THE MAIN LOW. ITS IMPACT ON THE CWA WILL DEPEND ON THE STRENGTH OF THE RIDGE...WHICH AT THIS POINT LOOK TO REMAIN FAIRLY FLAT/BROAD...NOT STRONG ENOUGH TO SHIFT THOSE BETTER CHANCES TO THE NORTH. PLENTY OF UNCERTAINTY ALREADY ON WEDNESDAY...SOME MODELS SHOW THE WEST WITH THE BETTER CHANCES/OTHERS THE EAST...AND DECIDED AT THIS POINT TO KEEP POPS ON THE LOWER SIDE. WEDNESDAY NIGHT...DIDNT MAKE SIGNIFICANT CHANGES TO THE POPS /WHICH REMAIN IN THE CHANCE CATEGORY/...WITH THERE STILL BEING SOME SUPPORT OF ANOTHER ROUND OF ACTIVITY FROM THE WEST SLIDING THROUGH...BUT WITH OTHERS STARTING TO TREND AWAY FROM THAT WASNT GOING TO INCREASE THOSE CHANCES. BY 12Z THURSDAY...MODELS STARTING TO DEPICT SOME SLIGHT AMPLIFICATION OF THE RIDGE OVER THE PLAINS AS THAT PAC NW LOW REMAINS IN PLACE. MAIN QUESTION IS WITH PRECIP CHANCES...AND WHAT/IF ANYTHING IS LINGERING IN THE EAST IN THE MORNING AND WILL ANYTHING FIRE IN THE WEST DURING THE AFTERNOON. ACCOMPANYING THIS BUMP UP IN THE RIDGE IS WARMING TEMPERATURES IN THE LOWER/MID LEVELS...AND CAPPING STARTS TO BECOME MORE OF A CONCERN. SOME MODELS HAVE STARTED TRENDING TOWARD THAT CAP BUILDING IN AND KEEPING THE DAY DRY...BUT A FEW ARE HANGING ON TO THE POTENTIAL FOR SOME LINGERING ACTIVITY...SO WHILE POPS WERE LOWERED...THEY WERE NOT COMPLETELY REMOVED AT THIS POINT. THE FORECAST FOR FRIDAY AND SATURDAY IS DRY. THOUGH THE UPPER LEVEL PATTERN IS BECOMING MORE SOUTHWESTERLY AS THE MAIN RIDGE AXIS BECOMES MORE ORIENTATED IN A SW/NE DIRECTION JUST EAST OF THE CWA...THE WARMER MID LEVEL TEMPS/CAPPING AND LOCATION OF SFC BOUNDARIES LOOKS TO KEEP THE BETTER CHANCES JUST OFF TO THE CWA. FOR SUNDAY AND MONDAY...PRECIP CHANCES LOOK TO MAKE A RETURN TO THE CWA. THE LOW OVER THE PAC NW FINALLY STARTS TO SHIFT TO THE E/NE INTO CENTRAL CANADA...BREAKING DOWN/SHIFTING THE RIDGE ONCE IN PLACE OVER THE CENTRAL PLAINS...AND AGAIN ALLOWING FOR THE OPPORTUNITY FOR DISTURBANCES IN THE MAIN FLOW TO BRING CHANCES FOR THUNDERSTORMS. AS FAR AS TEMPERATURES GO...EXPECTING TO SEE A GRADUAL WARMING TREND...MAINLY INTO THE FRI/SAT TIMEFRAME WITH THAT AMPLIFICATION OF THE RIDGE...BEFORE MODERATING BACK DOWN A TOUCH INTO SUN/MON. CURRENTLY HAVE HIGHS RISING TO THE 90S FOR BOTH FRI AND SAT /ADDITION UPWARD ADJUSTMENTS MAY BE NEEDED/...WITH MID 80S TO MID 90S FOR SUN/MON. && .AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1235 PM CDT MON JUN 17 2013 ALTHOUGH CONFIDENCE REMAINS REASONABLY HIGH IN VFR CEILING/VISIBILITY THROUGH THE NEXT 24 HOURS...CONFIDENCE IN THUNDERSTORM TIMING/PROBABILITY OF OCCURRENCE REMAINS RATHER MURKY IN THIS WEAKLY-FORCED NORTHWEST-FLOW PATTERN. ALTHOUGH HAVE MAINTAINED SEVERAL HOURS OF VICINITY THUNDERSTORM MENTION TO AT LEAST HINT AT THE POSSIBILITY OF OCCURRENCE...HAVE DELAYED THIS MENTION TO THE EVENING/OVERNIGHT HOURS AND REMOVED FROM THIS AFTERNOON. KEEP IN MIND THAT TEMPO/PREVAILING GROUPS WILL BE ADDED IF CONFIDENCE INCREASES IN STORMS DIRECTLY AFFECTING KGRI...AS ANY STORMS COULD CONTAIN GUSTY WINDS AS WELL. OTHERWISE...GENERALLY LIGHT BREEZES UNDER 10KT WILL PREVAIL THROUGH THE PERIOD...TRANSITIONING FROM NORTHEASTERLY TO SOUTHEASTERLY WITH TIME. ALTHOUGH SUPPOSE LIGHT FOG WITH MVFR VISIBILITY CANNOT COMPLETELY BE RULED OUT OVERNIGHT...WILL LEAVE IT VFR FOR NOW GIVEN THE SEEMINGLY LOW PROBABILITY OF OCCURRENCE. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...PFANNKUCH LONG TERM...ADO AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1235 PM CDT MON JUN 17 2013 .UPDATE... ISSUED AT 1055 AM CDT MON JUN 17 2013 FIRST FORECAST UPDATE OF THE DAY JUST COMPLETED. TO MAKE A LONG STORY SHORT...AM GROWING LESS AND LESS IMPRESSED WITH THUNDERSTORM POTENTIAL ESPECIALLY IN THE NOON-3 PM TIME FRAME...AS INSTABILITY/FORCING FOR ROBUST EARLY-MID AFTERNOON DEVELOPMENT EVEN JUST NORTHWEST OF THE CWA APPEARS TO BE CONSIDERABLY LACKING COMPARED TO YESTERDAY. EVEN BY 21Z...THE LATEST RAP-ADVERTISED 0-1KM MLCAPE RANGES FROM BARELY ANYTHING IN EASTERN ZONES...MAYBE AROUND 500-1000 J/KG CENTRAL...AND UP TO 1000-1500 J/KG...AND EVEN THEN A BIT OF A CAP IS IN PLACE. FOR THE NEXT SEVERAL HOURS...WE ARE LIKELY TO BE DOMINATED BY SUBSIDENCE IN THE WAKE OF DECENT SHORTWAVE TROUGH DEPARTING THROUGH SOUTHEAST KS...WHILE WEAK UPSTREAM WAVE CROSSING NORTHWEST/NORTH CENTRAL NEBRASKA IS CURRENTLY HAVING TROUBLE GENERATING MORE THAN SPRINKLES/LIGHT SHOWERS GIVEN MEAGER INSTABILITY. AT SOME POINT LATER THIS AFTERNOON/EVENING...SOME ACTIVITY THAT DEVELOPS WEST-NORTHWEST OF THE CWA COULD STILL MOVE IN AND BE STRONG/MARGINALLY SEVERE...BUT AT LEAST FOR NOW AM GOING TO START DOWNPLAYING THE AFTERNOON HOURS AND DELAY ANY MENTION OF STORMS UNTIL 20Z/3PM...AND EVEN THEN ONLY 20-30 PERCENT CHANCES THROUGH 00Z/7PM WITHIN ABOUT THE NORTHWEST 2/3 OF THE CWA. WILL REFINE THE EVENING/OVERNIGHT POPS IN LATER UPDATES...BUT ITS WORTH NOTING THAT THE LATEST HRRR DOESN/T BRING A SINGLE STORM INTO THE CWA UNTIL AFTER 01Z/8PM...AND EVEN THEN ONLY FOR THE FAR NORTHWEST/WEST COUNTIES. THIS IS NO GUARANTEE THOUGH...AS MODELS CONTINUE TO STRUGGLE WITH DETAILS IN THIS PATTERN. OTHERWISE...MADE NO CHANGES WHATSOEVER TO HIGH TEMP FORECAST AT THIS TIME...BUT DID LOWER DEWPOINTS A FEW DEGREES BASED ON CURRENT TRENDS...WITH MANY CENTRAL/NORTHEAST COUNTIES RUNNING DOWN IN THE UPPER 50S VERSUS 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 355 AM CDT MON JUN 17 2013 OVERALL PATTERN TODAY IS RATHER SIMILAR TO YESTERDAY WITH AN UPPER RIDGE CENTERED OVER THE ROCKIES...AND NORTHWESTERLY FLOW ALOFT ACROSS THE PLAINS. WEAK EMBEDDED SHORT WAVES WILL CONTINUE TO TRACK ACROSS THE PLAINS. THE 00Z ECMWF...00Z AND 06Z NAM...AND SEVERAL WFR RUNS ONCE AGAIN INITIATE CONVECTION ACROSS THE NEBRASKA SANDHILLS BY LATER THIS MORNING INTO EARLY THIS AFTERNOON. THIS CONVECTION SHOULD TRACK SOUTHEAST WITH ADDITIONAL CONVECTIVE DEVELOPMENT PROPAGATING TO THE SOUTHEAST THROUGH THE AFTERNOON. THIS WILL RESULT IN THE CHANCE OF THUNDERSTORMS AGAIN FOR OUR AREA ESPECIALLY DURING THE AFTERNOON WITH THE FOCUS BEING ONCE AGAIN ACROSS OUR WESTERN ZONES...WEST OF HIGHWAY 281. THE HIGHEST POPS THIS AFTERNOON WILL BE ACROSS OUR FAR WEST AND THEN DECREASE TO LOW END SLIGHT CHANCE POPS ACROSS OUR NORTHEAST. THUNDERSTORMS MAY NOT BE QUITE AS WIDESPREAD ACROSS OUR AREA TODAY...BUT ANY STORMS THAT DO FORM OR MOVE INTO THE REGION WILL CERTAINLY BE CAPABLE OF PRODUCING SEVERE WEATHER. ANY SEVERE WEATHER SHOULD BE CONFINED TO THIS AFTERNOON AND EVENING WITH THE FOCUS ONCE AGAIN BEING WEST OF HIGHWAY 281. INSTABILITY WILL AGAIN BE HIGH TODAY WITH MLCAPE VALUES OF 2000 TO 2500 J/KG...AND 0-6 KM DEEP LAYER SHEAR WILL BE ADEQUATE FOR SEVERE WEATHER AT 30 TO 40 KTS. THERE IS ALSO LITTLE IF ANY CONVECTIVE INHIBITION BY EARLY AFTERNOON AND THE QUESTION WILL BE CAN WE GET ENOUGH FORCING OR MOVE SOME STORMS INTO OUR FAVORABLE ENVIRONMENT THIS AFTERNOON FROM THE NORTHWEST. CURRENT THOUGHT IS THAT WE WILL HAVE AT LEAST A FEW THUNDERSTORMS ACROSS THE AREA THIS AFTERNOON...PRIMARILY WESTERN AREAS...BUT MAYBE A FEW LESS STORMS OVERALL THAN WE HAD YESTERDAY. THUNDERSTORMS COULD LINGER INTO THE EVENING...BUT SHOULD DIE DOWN FAIRLY QUICKLY AFTER SUNSET AS WE LOSE HEATING. HIGH TEMPERATURES TODAY WILL BE SIMILAR TO YESTERDAY AND RANGE FROM THE LOWER TO MID 80S ACROSS NEBRASKA...TO THE MID AND UPPER 80S OVER NORTHERN KANSAS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 355 AM CDT MON JUN 17 2013 ALOFT: THE LONG-WAVE /LGWV/ RIDGE WILL HAVE RETROGRADED TO THE ROCKIES BY 12Z/TUE. A CLOSED LOW WILL BE OFF THE PAC NW COAST. THE RIDGE WILL BE SHOVED BACK OVER THE PLAINS WED-THU AS THE SLOW-MOVING LOW ADVANCES INTO THE PAC NW. BY FRI THE LOW WILL ONLY HAVE ADVANCED INTO SRN ALBERTA. THE LGWV RIDGE WILL BE OVER THE MID MS VALLEY AND FAIRLY ZONAL W FLOW WILL BE OVER THE CNTRL PLAINS. SFC: THE MEAN POLAR FRONT WILL BE NEAR I-70 AT 12Z/TUE AND GRADUALLY SINK FURTHER S TUE-WED...AS THE ERN USA TROF MODESTLY DEEPENS. IN THE MEANTIME...HIGH PRES WILL REMAIN PARKED OVER THE NE 1/4 OF THE USA. THE TAIL END OF THE POLAR FRONT WILL LIFT BACK N INTO THE CNTRL PLAINS WED NGT INTO THU...AS PRES FALLS AND A NEW LEE LOW FORMS OVER CO. WHILE WE WILL PROBABLY SEE A LULL IN TSTM ACTIVITY /MOST LIKELY TUE-WED/...TSTM ACTIVITY IS EXPECTED TO INCREASE AS THE FRONT LIFTS BACK N WED NGT-THU...ALONG WITH THE LEADING EDGE OF A FRESH EML ADVECTING OFF THE ELEVATED DESERTS/ ROCKIES. HOWEVER...BY FRI THE CO LOW IS FCST TO EJECT NE ACROSS NEB TO MN. IT APPEARS THAT THE POLAR FRONT WILL STALL ACROSS THE FCST AREA FRI-SUN WITH MULTIPLE WAVES OF LOW PRES TRACKING NE ALONG THE FRONT. THE EML WILL PROBABLY CAP MOST TSTM DEVELOPMENT S OF THE FRONT. MULTIPLE MCS COMPLEXES WILL OCCUR N OF THE FRONT...MOST LIKELY FROM THE DAKOTAS INTO MN/IA/MO. FCST CONFIDENCE: OVERALL BELOW AVERAGE DUE TO INHERENT UNCERTAINTY ASSOCIATED WITH TSTMS AND THEIR ASSOCIATED EFFECTS IN THE MODELS. THE DAILY DETAILS... TUE: EXPECT SOME CLOUD DEBRIS FROM THE REMNANTS OF MON NGT TSTMS OVER WRN KS/NEB. TSTMS WILL REDEVELOP OVER THOSE SAME AREAS AFTER 3 PM AND MAY EVENTUALLY DRIFT INTO PARTS OF THE FCST AREA W OF HWY 281. NEAR NORMAL TEMPS BEHIND THE FRONT. 1-2F COOLER THAN PREVIOUS FCST. TUE NGT-WED: THE GFS/EC BOTH HAVE WHAT APPEAR TO BE THE LEADING SHRTWV TROF /ASSOCIATED WITH THE PAC NW CLOSE LOW/ MOVING THRU HERE...SUGGESTING THAT SHWRS/TSTMS COULD BE POSSIBLE AT ANY TIME. NEAR NORMAL TEMPS. 1-2F COOLER THAN PREVIOUS FCST. WED NGT: POSSIBLE MCS DEVELOPMENT? 40 KT LLJ PUNCHES OVER THE LIFTING WARM FRONT. THU: SOME LINGERING MRNG RAIN SOMEWHERE? WE MAY HAVE TO DEAL WITH PLENTY OF MRNG CLOUDS BEHIND A DEPARTING TSTM COMPLEX...IF IT MATERIALIZES. THE AFTN SHOULD TURN SUNNY. N-CNTRL KS SHOULD BE BACK IN THE 90S. TEMPS 3-5F ABOVE NORMAL. FRI-SAT: MOST LIKELY CAPPED AND WE HEAT IT BACK UP. BEAVER CITY NEB-STOCKTON KS BACK TO 100F? TEMPS 10F ABOVE NORMAL. && .AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1235 PM CDT MON JUN 17 2013 ALTHOUGH CONFIDENCE REMAINS REASONABLY HIGH IN VFR CEILING/VISIBILITY THROUGH THE NEXT 24 HOURS...CONFIDENCE IN THUNDERSTORM TIMING/PROBABILITY OF OCCURRENCE REMAINS RATHER MURKY IN THIS WEAKLY-FORCED NORTHWEST-FLOW PATTERN. ALTHOUGH HAVE MAINTAINED SEVERAL HOURS OF VICINITY THUNDERSTORM MENTION TO AT LEAST HINT AT THE POSSIBILITY OF OCCURRENCE...HAVE DELAYED THIS MENTION TO THE EVENING/OVERNIGHT HOURS AND REMOVED FROM THIS AFTERNOON. KEEP IN MIND THAT TEMPO/PREVAILING GROUPS WILL BE ADDED IF CONFIDENCE INCREASES IN STORMS DIRECTLY AFFECTING KGRI...AS ANY STORMS COULD CONTAIN GUSTY WINDS AS WELL. OTHERWISE...GENERALLY LIGHT BREEZES UNDER 10KT WILL PREVAIL THROUGH THE PERIOD...TRANSITIONING FROM NORTHEASTERLY TO SOUTHEASTERLY WITH TIME. ALTHOUGH SUPPOSE LIGHT FOG WITH MVFR VISIBILITY CANNOT COMPLETELY BE RULED OUT OVERNIGHT...WILL LEAVE IT VFR FOR NOW GIVEN THE SEEMINGLY LOW PROBABILITY OF OCCURRENCE. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...PFANNKUCH SHORT TERM...WESELY LONG TERM...HALBLAUB AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
926 PM MDT TUE JUN 18 2013 .UPDATE... ALLOWED SEVERE THUNDERSTORM WATCH TO EXPIRE AS SCHEDULED WITH STORMS JUST IN UNION COUNTY AT THIS TIME. JURY STILL OUT ON WHETHER WE WILL SEE MUCH OF AN EAST WIND INTO THE RGV LATER TONIGHT...SETUP DIFFERENT THAN LAST NIGHT. RUC13 HAS BEEN BACKING OFF ON A STRONG GRADIENT UNTIL AFTER MIDNIGHT OR EVEN TOWARDS SUNRISE. WILL KEEP MONITORING. ZFP ALREADY OUT. && .PREV DISCUSSION...551 PM MDT TUE JUN 18 2013... .AVIATION... 00Z TAF CYCLE CONVECTION HAS SO FAR BEEN BELOW EARLIER EXPECTATIONS. ISO-SCT TSRA WILL CONTINUE ACROSS FAR NE NM...BUT CONFIDENCE IS MODERATE TO LOW ON WHETHER THE CURRENT CONVECTION ACROSS NE NM AND SE CO WILL ORGANIZE INTO A MCS AND MOVE SOUTHEAST...AS SOME MODELS SUGGEST. IF IT DOES...TCC WOULD STAND TO HAVE THE GREATEST IMPACTS...THOUGH SCALED BACK MENTION OF TS AND RA IN LATEST TAF ISSUANCE. WITH THIS IN MIND...STRENGTH OF THE GAP WINDS THROUGH THE CENTRAL MTNS ALSO REMAINS IN QUESTION. KEPT FCST ABOVE GUIDANCE...BUT THIS MAY NEED TO BE TWEAKED DOWN...ESPECIALLY IN ABQ TAF. ALSO CANT RULE OUT LOW CIGS DEVELOPING OVERNIGHT ACROSS THE FAR EASTERN PLAINS...MAINLY ALONG AND EAST OF A LINE FROM RTN TO CVS...DUE TO HIGHER MOISTURE IN PLACE. 34 && .PREV DISCUSSION...307 PM MDT TUE JUN 18 2013... ...SEVERE THUNDERSTORM WATCH 325 IN EFFECT UNTIL 9 PM MDT... STORM COVERAGE IS MUCH MORE LIMITED TODAY AS POTENT DRY AIR ALOFT MOVES OVER THE REGION ON INCREASING SOUTHWESTERLY FLOW. LOW LEVEL MOISTURE DID MAKE IT ALL THE WAY TO THE DIVIDE BUT IT IS SHALLOW AND WILL CONTINUE MIXING OUT THIS AFTERNOON. THIS GRADIENT ACROSS THE AREA ALONG WITH AFTERNOON HEATING AND TOPOGRAPHIC FORCING WILL SET THE STAGE FOR SEVERE STORMS OVER THE NE PLAINS. LATEST RADAR TRENDS SHOW A POTENTIAL SEVERE STORM WEST OF RATON...AND THIS IS EXPECTED TO CONTINUE THROUGH THE EVENING AS THE ATMOSPHERE BECOMES MORE UNSTABLE. RAISED POPS FOR THE NE AND EAST CENTRAL PLAINS AND LOWERED A LITTLE FARTHER WEST. WEDNESDAY WILL BE AN UGLY FIRE DANGER DAY ACROSS THE REGION WITH DEEP MIXING TAPPING VERY DRY AIR LEADING TO HOT...BREEZY/WINDY... AND UNSTABLE CONDITIONS. 700MB TEMPS WILL BE NEAR +18C WHICH IS NOT AS WARM AS WHAT WE EXPERIENCED LAST WEEK HOWEVER IT IS STILL WELL ABOVE NORMAL. TOSSED IN SOME SYNOPTICALLY DRIVEN BLOWING DUST INTO THE GRIDS FOR A FEW CENTRAL AND WESTERN LOCALES. ANY STORMS WILL BE FOCUSED ACROSS THE PLAINS AND EVEN THERE EXPECT MOSTLY DRY AND GUSTY ACTIVITY. THURSDAY WILL BE SIMILAR TO WEDNESDAY EXCEPT MORE MOISTURE WILL TRICKLE NORTH ACROSS THE SE HALF OF THE AREA. RAISED POPS JUST A TAD FARTHER NORTH AS THE 12Z NAM IS BULLISH ON DEVELOPING ACTIVITY UP TO THE I-40 CORRIDOR. TEMPS WILL REMAIN HOT AND WINDS ALOFT WILL STAY STRONG SO BREEZY CONDITIONS CAN BE EXPECTED. ANY SHOWERS/STORMS THAT GET GOING WILL HAVE POTENTIAL TO PRODUCE STRONG OUTFLOW WINDS. QUITE A LARGE AMOUNT OF UNCERTAINTY REMAINS WITH MEDIUM/EXTENDED RANGE GUIDANCE FOR FRIDAY THRU EARLY NEXT WEEK. THE GFS ENSEMBLE PWAT SHOWS A LARGE SWATH OF 1-2 STDEV BELOW CLIMO VALUES FROM THE NORTHERN BAJA REGION ACROSS THE GREAT BASIN...WITH NEAR CLIMO VALUES FOR NM. THE ECMWF IS SIGNIFICANTLY DRIER THRU THIS PERIOD WITH THE UPPER RIDGE AXIS STRETCHING FROM WSW TO ENE ACROSS NORTHERN MEXICO. THIS SHUTS OFF ANY STREAM OF MOISTURE SLIDING INTO OUR AREA THRU ALL OF NEXT WEEK WITH A 598DM RIDGE BUILDING RIGHT OVER NORTHERN NM AND SOUTHERN CO. THIS WOULD LEAD TO WELL ABOVE NORMAL SCORCHING TEMPS ONCE AGAIN. THE GFS HOWEVER DOES TAKE A PIECE OF THE CURRENT TROPICAL DISTURBANCE OVER SOUTHERN MEXICO AND LIFTS IT NORTH WITH THE RIDGE FARTHER EAST. FOR NOW WILL SIDE WITH THE DRIER SOLUTION AND KEEP POPS VERY LOW IN THE EXTENDED. GUYER && .FIRE WEATHER... ...CRITICAL FIRE WEATHER PERIOD NEXT FEW DAYS... MODEL GUIDANCE HAS SUGGESTED A LITTLE STRONGER FLOW FOR PORTIONS OF THE FORECAST AREA WEDNESDAY SO RAISED SPEEDS SLIGHTLY BUT PRETTY SIMILAR TO ORIGINAL LEVELS. THE HIGHER RIDGES AND AREAS NEAR THE AZ/CO STATE LINES AS WELL AS TO THE LEE OF THE CENTRAL MOUNTAINS WILL BE FAVORED FOR THE STRONGEST WINDS. LATEST MODEL GUIDANCE ALSO SUGGEST THE STRONGEST WINDS ALOFT WEDNESDAY NIGHT INTO THURSDAY SO BUMPED UP WIND SPEEDS ACCORDINGLY. GETTING MORE CRITICAL FIRE WEATHER CONDITIONS FOR THURSDAY. ONLY FLY IN THE OINTMENT IS THE 12Z NAM/S DEPICTION OF MID LEVEL MOISTURE FLOWING UP FROM MEXICO THURSDAY AFTERNOON. OTHER MODELS NOT AS AGGRESSIVE. COULD BE A WILD AND WOOLLY DAY WITH A MIX OF STANDARD RED FLAG CONDITIONS PLUS DRY MICROBURST WINDS DUE TO DRIER STORMS. WILL MONITOR THAT TREND ACCORDINGLY. WILL UPGRADE WATCH TO A WARNING FOR THE ENTIRE FORECAST AREA EXCLUDING AREAS NEAR TO THE TEXAS STATE LINE DUE TO HIGHER RH THERE WEDNESDAY. WILL ISSUE A WATCH FOR THE WESTERN TWO THIRDS OF THE FORECAST AREA ON THURSDAY. GOING TO BE ON THE SAFE SIDE FOR BOTH DAYS. AS FAR AS REST OF TODAY...LOOKING AT SOME DRIER STORMS ACROSS THE NORTH CENTRAL MOUNTAINS AS THE DRY AIR RAPIDLY PUSHES FROM WEST TO EAST. THESE STORMS WILL TEND TO BE FAST MOVING. THE WETTER STORMS WILL BE FOUND ACROSS THE EASTERN PLAINS...ESPECIALLY FAVORING THE NORTHEAST. UPPER FLOW WILL INCREASE OVER NORTHERN AND CENTRAL NEW MEXICO TONIGHT AS THE UPPER RIDGE SLIDES SLIGHTLY TO THE EAST. TEMPERATURES WILL BE ABOVE NORMAL. THE MID LEVEL DRY INTRUSION WILL FILTER FURTHER OVER THE FORECAST AREA ALTHOUGH ABUNDANT LOW LEVEL MOISTURE WILL TRY TO PUSH BACK TO THE WEST SIMILAR TO LAST NIGHT BUT NOT AS AGGRESSIVE. HUMIDITY RECOVERIES WILL BE VERY POOR NEAR TO THE AZ STATE LINE...POOR BETWEEN THE CONTINENTAL DIVIDE TO RIO GRANDE VALLEY AND THEN MODERATE TO GOOD FURTHER EAST. EVEN EXCELLENT NEAR THE TEXAS STATE LINE. WEDNESDAY WILL BE A HIGHER END CRITICAL DAY DUE TO THE TIME OF YEAR AND COMBO WIND/LOW RH/ABUNDANT TURBULENT MIXING AND QUITE A BIT OF SUNSHINE. SUN ANGLES ARE GETTING TO BE QUITE STEEP AND THE MID LEVEL DRY INTRUSION IS EXPECTED TO BE QUITE STRONG AS IT PUSHES FURTHER EASTWARD OVER THE STATE. SUPER HAINES VALUES ARE PROJECTED FOR WESTERN AND NORTHERN NEW MEXICO. THE SURFACE WIND FLOW WILL BE HERKY JERKY OR PULSY DUE TO THE TURBULENT MIXING AND ABOVE NORMAL TEMPERATURES. MIXING HEIGHTS ARE PROJECTED TO BE ABOVE NORMAL WITH SOME PRETTY STOUT SOUTHWEST TRANSPORT WINDS. SEVERAL HOURS OF SINGLE DIGITS ARE EXPECTED ALONG AND JUST TO THE LEE OF THE CENTRAL MTNS WESTWARD TO ARIZONA. THE HEART OF THE SINGLE DIGIT AREA IN TERMS OF 10 TO 15 HOURS INCLUDES THE NORTHWEST HALF OF THE FORECAST AREA. STORM POTENTIAL...MAINLY OF THE DRIER VARIETY WILL BE FOUND ACROSS THE EASTERN PLAINS AND CANT RULE OUT A ROGUE DRY STORM ALONG THE EAST SLOPES OF THE SANGRES BEFORE THE DRY AIR REALLY PUSHES IN. THE RIDGE WILL NUDGE A LITTLE FURTHER TO THE EAST WEDNESDAY NIGHT AS THE MID LEVEL DRY INTRUSION PROCEEDS OVER THE ENTIRE AREA. TEMPERATURES WILL REMAIN WARMER THAN NORMAL WITH POOR TO VERY POOR RECOVERIES WESTERN TWO THIRDS OR SO. MUCH BETTER RECOVERIES WITH RESIDUAL HIGHER LOW LEVEL MOISTURE WILL BE FOUND NEAR THE TEXAS STATE LINE. THE HIGHER RIDGES SHOULD CONTINUE TO SEE STEADY WIND FLOWS AS THE UPPER FLOW STRENGTHENS SOME. THIS WILL LEAD INTO ANOTHER POTENTIALLY CRITICAL DAY ON THURSDAY. THE UPPER FLOW WILL REMAIN PRETTY STRONG AND FAVOR THE SAME AREAS AS MENTIONED DURING THE OPENING PARAGRAPH. TEMPERATURES WILL REMAIN ABOVE NORMAL ALTHOUGH HUMIDITY VALUES COULD RISE SOME AS COMPARED TO WEDNESDAY/S READINGS. NAM MODEL A LITTLE JUMPY WITH ITS DEPICTION OF A MID LEVEL MOISTURE PUSH FROM MEXICO. THE 12Z MODEL WAS MORE MOIST WHILE THE 18Z IS COMING IN DRIER. IF STORMS DO FORM THEY WOULD BE DRIER AND FASTER MOVING LEADING TO AN ADDITIONAL IGNITION THREAT. EITHER WAY...GETTING ENOUGH CRITICAL WIND SPEEDS COMBINED WITH LOW HUMIDITY AND ABOVE NORMAL MIXING TO WARRANT A FIRE WEATHER WATCH. SEEING A SUPER HAINES SIGNATURE ACROSS THE NORTHWEST THIRD OR SO BUT LESS AREA THAN IS EXPECTED WEDNESDAY. EXTENDED MODELS SUCH AS THE GFS AND ECMWF POINT TOWARDS AN UPPER SOUTHWEST FLOW CONTINUING FRIDAY AND INTO THE WEEKEND. DECIDED TO UP WIND SPEEDS SLIGHTLY FOR FRIDAY AND SEEING SOME LOCALIZED CRITICAL CONDITIONS BUT DOESNT APPEAR TO BE AS STRONG OF A SIGNAL AS THE PREVIOUS DAYS. UPPER FLOW IS DEPICTED TO WEAKEN SOME AS THE PACIFIC TROUGH SHEARS OUT. EXPECTING SOME SORT OF MID LEVEL MOISTURE SEEPAGE FROM MEXICO DURING THIS PERIOD WITH MORE OF A MOISTURE RETURN FROM THE GULF ACROSS THE SOUTHEAST AND EAST CENTRAL PLAINS. THE WETTER STORMS COULD BE POSSIBLE THERE WHILE THE DRIER VARIETY ELSEWHERE. TEMPERATURES WOULD BE A FEW DEGREES ABOVE NORMAL DURING THIS PERIOD WITH MUCH LOWER HUMIDITY VALUES WEST. CONFIDENCE IN THIS PERIOD IS MODERATE ALTHOUGH LOTS OF UNCERTAINTY ON THE MOISTURE PUSH. 50 && .ABQ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TO 8 PM MDT WEDNESDAY FOR THE FOLLOWING ZONES...NMZ101>109. FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR THE FOLLOWING ZONES...NMZ101>103-105>107-109. && $$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
103 AM EDT MON JUN 17 2013 .SYNOPSIS... A WAVE OF LOW PRESSURE ASSOCIATED WITH THE UPPER LEVEL TROUGH WILL BRING A WEAK COLD FRONT ACROSS THE REGION ON MONDAY...BRINGING SHOWERS AND A FEW THUNDERSTORMS THROUGH MONDAY NIGHT. A LARGE AREA OF HIGH PRESSURE WILL THEN MOVE INTO THE GREAT LAKES...REMAINING NEARLY STATIONARY OVER THE REGION. THIS PATTERN WILL GENERATE SOME SUN ALONG WITH NEARLY SEASONAL TEMPERATURES. && .NEAR TERM /THROUGH TODAY/... A CLUSTER OF THUNDERSTORMS WHICH FORMED NORTH OF LAKE ONTARIO LAST EVENING CONTINUES TO SHIFT SOUTHEAST ACROSS LAKE ONTARIO EARLY THIS MORNING. SOME GUSTY WINDS AND POSSIBLE SMALL HAIL MAY EXIST WITHIN THE STRONGER CELLS. MESOANALYSIS SHOWS A WEAK POOL OF ELEVATED INSTABILITY...LESS THAN 500 J/KG SURFACE/MIXED LAYER CAPE...OVER THE FORECAST AREA THAT THESE STORMS ARE FEEDING ON. THE HRRR MODEL HAS CAPTURED THIS CLUSTER WELL AND SHOWS IT WILL CONTINUE SOUTHEAST WHILE WEAKENING SOME ONCE IT REACHES THE SOUTHEASTERN LAKE ONTARIO SHORELINE. FORECAST GRIDS HAVE BEEN UPDATED WITH THIS IN MIND. OUTFLOW BOUNDARIES SURGING SOUTH FROM THIS CLUSTER WILL BE WATCHED FOR TRIGGERING NEW CELLS FURTHER WEST NORTH OF THE NY THRUWAY. A SECOND MUCH SMALLER AREA OF THUNDERSTORMS HAS NOW SHIFTED SOUTH OF CHAUTAUQUA COUNTY INTO NORTHWESTERN PA. BROAD MID LEVEL TROUGHING ANCHORED ACROSS THE SOUTH CENTRAL CANADA WILL UNDERGO SOME STRENGTHENING WITH TIME OVER THE NEXT 24 HOURS WITH A CLOSED LOW EVOLVING OVER HUDSON BAY. THIS WILL PROMPT THE SOUTHERN EXTENSION OF THE MAIN HEIGHT FALL REGION TO SQUEEZE INTO THE PREVAILING MID LEVEL WESTERLIES POSITIONED OVER THE GREAT LAKES. THIS PROCESS WILL ALLOW A COLD FRONTAL BOUNDARY TO SETTLE SOUTHWARD INTO THE LOWER LAKES REGION DURING THE DAY MONDAY. SOLID WINDOW WILL EXIST TO CAPITALIZE ON DAYTIME HEATING WITH INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... DURING THE COURSE OF MONDAY NIGHT...THE COLD FRONT WILL CONTINUE TO SAG SOUTHWARD ACROSS THE AREA...WITH ADDITIONAL SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACCOMPANYING THE PASSAGE OF THIS FEATURE DURING THE EVENING. WILL CONTINUE TO INDICATE THE HIGHEST PRECIPITATION CHANCES /LIKELIES/ ACROSS THE NORTH COUNTRY WHERE FORCING AND MOISTURE WILL BE MOST CONCENTRATED...WITH CHANCE POPS FOR AREAS SOUTH OF LAKE ONTARIO. FOLLOWING THE FROPA...SCATTERED LEFTOVER SHOWERS WILL SLOWLY DIMINISH FROM NORTH TO SOUTH OVERNIGHT...WHICH WILL BE REFLECTED IN THE FORECAST WITH POPS GRADUALLY DIMINISHING THROUGH THE CHANCE RANGE. WITH A FAIR AMOUNT OF CLOUD COVER LINGERING IN PLACE AND COLD ADVECTION JUST STARTING TO SET UP BEHIND THE FRONT OVERNIGHT...TEMPS WILL NOT DROP OFF TOO MUCH...AND WILL GENERALLY BOTTOM OUT IN THE LOWER 50S ACROSS THE NORTH COUNTRY AND THE MID-UPPER 50S ELSEWHERE...OR RIGHT ABOUT NORMAL FOR MID JUNE. ON TUESDAY...THE COLD FRONT WILL CONTINUE TO SAG SOUTH TO THE VICINITY OF THE MASON-DIXON LINE...THOUGH A CONSENSUS OF THE 12Z GUIDANCE SUITE NOW SUGGESTS THAT THIS BOUNDARY WILL DEPART A LITTLE MORE SLOWLY THAN PREVIOUSLY FORECAST. CONSEQUENTLY...HAVE KEPT CLOUD COVER AND CHANCES FOR A LEFTOVER SHOWER OR TWO IN A LITTLE LONGER THAN IN PREVIOUS FORECASTS...THOUGH THE BULK OF THE DAY SHOULD STILL BE DRY WITH MOST AREAS SEEING A RETURN TO AT LEAST PARTIAL SUNSHINE BY AFTERNOON AS SPRAWLING CANADIAN HIGH PRESSURE OVER THE UPPER LAKES BEGINS TO TAKE HOLD. UNDER CONTINUED COOL AIR ADVECTION...850 MB TEMPS WILL DROP OFF TO +6C TO +10C...WHICH SHOULD RESULT IN HIGHS FALLING BACK TO BELOW NORMAL LEVELS IN THE UPPER 60S TO LOWER 70S. TUESDAY NIGHT...THE AFOREMENTIONED RIDGE WILL CONTINUE TO BUILD SOUTHEAST TOWARD OUR REGION ALONG WITH PROGRESSIVELY COOLER AND DRIER AIR...BEFORE SETTLING DIRECTLY ACROSS NEW YORK STATE FOR WEDNESDAY AND WEDNESDAY NIGHT. THIS WILL PROVIDE OUR AREA WITH TRANQUIL WEATHER FOR THE LATTER HALF OF THE PERIOD...ALONG WITH CONTINUED BELOW NORMAL TEMPERATURES. EXPECT NIGHTTIME LOWS TUESDAY NIGHT AND WEDNESDAY NIGHT TO DIP INTO THE MID TO UPPER 40S IN MOST LOCATIONS...WITH ONLY THE LAKE PLAINS REMAINING IN THE LOWER 50S. MEANWHILE...HIGHS ON WEDNESDAY SHOULD AGAIN RANGE WITHIN A FEW DEGREES OF 70. && .LONG TERM /THURSDAY THROUGH SUNDAY/... DURING THE FIRST COUPLE DAYS OF THE EXTENDED PERIOD...LINGERING BROAD/RELATIVELY FLAT TROUGHING ALOFT WILL GIVE WAY TO A MORE ZONAL FLOW ACROSS OUR REGION...WHILE SURFACE HIGH PRESSURE SLOWLY DRIFTS FROM THE SPINE OF THE APPALACHIANS TO A POSITION OFF THE EAST COAST BY FRIDAY. THIS WILL RESULT IN CONTINUED MAINLY DRY WEATHER THROUGH THE END OF THE WORK WEEK...THOUGH A COUPLE WEAK FEATURES DROPPING THROUGH THE BACKSIDE OF THE DEPARTING TROUGH COULD TOUCH OFF AN ISOLATED SHOWER OR TWO ACROSS THE SAINT LAWRENCE VALLEY/NORTH COUNTRY BOTH THURSDAY AND FRIDAY. AS WE GET INTO NEXT WEEKEND...INCREASING RETURN FLOW ON THE BACKSIDE OF THE RIDGE SHOULD PUMP SOMEWHAT MORE HUMID AIR BACK INTO OUR REGION...AND THIS COUPLED WITH DAYTIME HEATING AND THE APPROACH OF THE NEXT FRONTAL SYSTEM SHOULD EVENTUALLY RESULT IN A MORE GENERAL CHANCE OF SOME SCATTERED CONVECTION BY SATURDAY NIGHT AND SUNDAY. ACCORDINGLY...HAVE INDICATED POPS CLIMBING BACK TO LOW CHANCE LEVELS DURING THIS TIME FRAME. WITH RESPECT TO TEMPERATURES...THE ABOVE EVOLUTION IN THE PATTERN WILL ALSO RESULT IN READINGS MODERATING BACK TO NEAR NORMAL LEVELS BY THURSDAY...THEN TO AT LEAST A BIT ABOVE NORMAL FOR THE REMAINDER OF THE PERIOD. MORE SPECIFICALLY...DAYTIME HIGHS IN THE 70S ON THURSDAY SHOULD WARM BACK TO AT LEAST THE LOWER 80S FOR THE WEEKEND...WITH SOME READINGS IN THE MID 80S POSSIBLE DEPENDING ON BOTH THE EVENTUAL TEMPERATURES ALOFT AND THE AREAL COVERAGE OF ANY CONVECTION/ASSOCIATED CLOUD COVER. AS MENTIONED ABOVE...HUMIDITY LEVELS SHOULD ALSO BE ON THE RISE...WITH COMFORTABLE DEWPOINTS OF AROUND 50 ON THURSDAY CLIMBING BACK TO MODERATELY HUMID LEVELS IN THE LOWER 60S BY SUNDAY. && .AVIATION /05Z MONDAY THROUGH FRIDAY/... VFR FOUND AT THE TAF SITES EARLY THIS MORNING. SOME CONVECTION SHIFTING SOUTHEAST ACROSS LAKE ONTARIO IS NOT EXPECTED TO LARGELY IMPACT TERMINALS. MAY SEE A VCTS OR -TSRA AT KROC IF NEW CELLS DEVELOP ON STORM OUTFLOW. OTHERWISE...PARTIAL CLEARING AND DIMINISHING WINDS MAY ALLOW FOR ENOUGH RADIATIONAL COOLING OVER WET GROUNDS TO DEVELOP SOME LOWER CLOUDS AND FOG OVERNIGHT. KJHW MAY SEE CONDITIONS DOWN TO MVFR. ON MONDAY A CHANCE OF SHOWERS AND THUNDERSTORMS IS POSSIBLE WITH AFTERNOON HEATING AND BROAD UPPER LEVEL TROUGH BUILDING SOUTH OVER NEW YORK. OUTLOOK... MONDAY AND TUESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... CLUSTER OF THUNDERSTORMS IS FOUND OF LAKE ONTARIO EARLY THIS MORNING. THIS WILL SHIFT SOUTHEAST OVER THE EASTERN HALF OF THE LAKE EARLY THIS MORNING AND SHIFT OVER CENTRAL NEW YORK FROM THE LAKE. UNSETTLED CONDITIONS WHICH CONTINUE FOR THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL CONTINUE MONDAY INTO TUESDAY WITH BROAD UPPER LEVEL TROUGH OVER NEW YORK THEN BY WEDNESDAY HIGH PRESSURE WILL BUILD BACK ACROSS THE LOWER LAKES WITH TRANQUIL CONDITIONS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH/TMA NEAR TERM...SMITH/TMA/WCH SHORT TERM...JJR LONG TERM...JJR AVIATION...SMITH MARINE...SMITH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
916 PM CDT TUE JUN 18 2013 .UPDATE... ISSUED AT 916 PM CDT TUE JUN 18 2013 LATEST BOWMAN DOPPLER RADAR SHOWS AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS BEGINNING TO IMPINGE INTO SOUTHWEST HARDING COUNTY IN SOUTH DAKOTA. THE H85-H30 MEAN WIND WOULD CONTINUE TO MOVE THE PRECIPITATION AREA FROM SOUTHWEST TO NORTHEAST THIS EVENING. THE THE LATEST RAP INITIALLY HAS THE AREAL EXTENT OF THE AFOREMENTIONED PRECIPITATION TOO FAR NORTH...AND WILL MAKE ADJUSTMENTS WITH A HEAVIER BLEND OF THE NAM OVERNIGHT. STILL EXPECTING ISOLATED THUNDERSTORMS INTO FAR SOUTHWEST NORTH DAKOTA AS PREVIOUSLY FORECAST...AS A H85-H7 SATURATED POTENTIAL TEMP RIDGE AXIS RESIDES IN CLOSE PROXIMITY IN FAR SOUTHWEST NORTH DAKOTA AND THE ONGOING CONVECTION...ALONG WITH H85-H5 LAPSE RATES OF 7C/KM. THE ACTIVITY SHOULD WEAKEN THEREAFTER...AND HAVE TAPERED OFF POPS TO LESS THAN MEASURABLE INTO SOUTH CENTRAL NORTH DAKOTA OVERNIGHT. ALTHOUGH CLOUD DEBRIS/ACCAS (ALTOCUMULUS CASTELLANUS) SHOULD BE VISIBLE LATER TONIGHT INTO EARLY WEDNESDAY MORNING AS INSTABILITY SHIFTS INTO NORTH DAKOTA. ELSEWHERE...CLOUDS ARE ALSO INCREASING IN NORTHEAST MONTANA AS A CIRRUS CANOPY SHIFTS EAST FROM THE THUNDERSTORMS IN NORTH CENTRAL MONTANA. WILL CONTINUE TO INCREASE CLOUDS OVERNIGHT WEST AND SOUTH CENTRAL. EXPECTATIONS ARE ISOLATED CONVECTION WILL BE CONFINED TO THE SOUTHWEST ZONES OVERNIGHT AND DRY CONDITIONS ELSEWHERE. UPDATE ISSUED AT 624 PM CDT TUE JUN 18 2013 LATEST WATER VAPOR IMAGERY THIS EVENING SHOWS A MID/UPPER LEVEL DISTURBANCE ROTATING THROUGH CENTRAL NORTH DAKOTA AT THIS TIME. VISIBLE SATELLITE IMAGERY AND SURFACE OBS SHOW SCT MID LEVEL CLOUDS STRETCHING FROM ROSEGLEN TO NEAR DICKINSON...WITH A SCT FAIR WEATHER CUMULUS FIELD ACROSS SOUTH CENTRAL AND EAST CENTRAL NORTH DAKOTA. WITH A H7-H5 RIDGE AXIS ANCHORED FROM WILLISTON TO BISMARCK AND INTO SIOUX FALLS SOUTH DAKOTA TONIGHT...EXPECT A DRY NIGHT ALONG AND EAST OF THE AFOREMENTIONED RIDGE AXIS. ATTENTION THIS EVENING AND OVERNIGHT TURNS TO AN UPSTREAM SHORTWAVE OVER SOUTHEAST WYOMING. THIS IS GENERATING THUNDERSTORMS IN THE HIGHER TERRAIN OF WYOMING...WITH A LARGE MID/HIGH LEVEL CLOUD CANOPY EXPANDING OVER EASTERN WYOMING AND SOUTHEAST MONTANA. THIS IS MOVING NORTHEAST AND WILL SLIDE INTO OUR SOUTHWEST ZONES THIS EVENING. THE LATEST RAP ADVECTS SOME LIGHT PRECIPITATION INTO THE FAR SOUTHWEST ZONES TOWARD 06Z. THE 18Z GFS IS MORE ROBUST IN GENERATING A LARGER SWATH OF LIGHT PRECIPITATION LATE TONIGHT THROUGH MID MORNING WEDNESDAY IN SOUTHWEST NORTH DAKOTA AND JUST GRAZING OUR SOUTH CENTRAL ZONES. HOWEVER OTHER MODELS DELAY THE SHOWERS/THUNDERSTORMS WITH THIS SHORTWAVE UNTIL WEDNESDAY AFTERNOON AND EVENING. WILL AWAIT THE 00Z DATA BEFORE MAKING ANY CHANGES BEYOND TONIGHT. WILL ALSO MONITOR THE CONVECTION APPROACHING THE SOUTHWEST THIS EVENING/OVERNIGHT. ONLY UPDATES THIS EVENING WAS TO HOURLY OBS AND TO INCREASE SKY GRID TRENDS IN THE SOUTHWEST AS MENTIONED ABOVE. THE CLOUD DEBRIS MAY MAKE IT INTO SOUTH CENTRAL NORTH DAKOTA BEFORE SUNRISE WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 324 PM CDT TUE JUN 18 2013 SURFACE TROUGH AND ASSOCIATED WARM FRONTAL BOUNDARY IN EASTERN MONTANA WILL BE THE FOCUS FOR SCATTERED THUNDERSTORMS LATE TONIGHT AND WEDNESDAY AFTERNOON. ANTICIPATE SOME THUNDERSTORMS WILL FIRE OVER THE HIGHER ELEVATION AREAS IN WYOMING/MONTANA/SOUTH DAKOTA AND DRIFT INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT. ON WEDNESDAY ONE LIMITING FACTOR WILL BE A SLOWING EVOLVING ELEVATED MIXED LAYER THAT MAY CAP THUNDERSTORMS OVER WESTERN NORTH DAKOTA WEDNESDAY AFTERNOON. HOWEVER BELIEVE THE INCREASING LOW LEVEL JET AND SIGNIFICANT CAPE VALUES JUSTIFY SCATTERED THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA WEDNESDAY AFTERNOON. WINDS ON WEDNESDAY SHOULD APPROACH BUT REMAIN BELOW WIND ADVISORY CRITERIA SOUTHWEST...PROBABLY 20 TO 35 MPH. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 324 PM CDT TUE JUN 18 2013 THE MAIN FORECAST ISSUE THROUGH THE LONG TERM PERIOD IS CONVECTIVE TRENDS AND POTENTIAL FOR PERIODS OF STRONG TO SEVERE STORMS...SOME ACCOMPANIED BY HEAVY RAINFALL. THE RUNS OF THE GFS/ECMWF ARE IN GENERAL AGREEMENT WITH A SLOWER PROGRESSION OF A LARGE CLOSED UPPER LOW IN THE PACIFIC NORTHWEST EARLY IN THE PERIOD...WITH THE NAM FASTEST IN BRINGING THE MAIN SYNOPTIC FEATURES EASTWARD. HAVE FAVORED THE GFS/EC SOLUTIONS FOR POPS WEDNESDAY NIGHT AND THURSDAY. THERE IS SOME POTENTIAL FOR AN MCS TO CLIP NORTHWEST COUNTIES LATE WEDNESDAY NIGHT INTO THURSDAY MORNING...FUELED BY A 40-50 KT LOW LEVEL JET. THE MAIN DECISION-MAKING ELEMENT WAS WHEN/WHERE THE STRONG MID-LEVEL CAP WOULD INHIBIT CONVECTION...BECAUSE OTHERWISE PLENTY OF CAPE AND SHEARING FOR SEVERE THUNDERSTORMS. WEDNESDAY EVENING THE AXIS OF THE MID-LEVEL CAP OF 10-14C IS SITUATED OVER WYOMING/EASTERN MONTANA AND NUDGING INTO SOUTH DAKOTA AND FAR SOUTHWESTERN NORTH DAKOTA. THE CAP BUILDS DURING THE EVENING NORTHWARD AND EASTWARD ACROSS THE DAKOTAS. AT THIS TIME IT APPEARS THE BEST CHANCE OF SEVERE THUNDERSTORMS BEGINS IN FAR WESTERN NORTH DAKOTA LATE EVENING WEDNESDAY OR EARLY MORNING THURSDAY...WITH SEVERE THUNDERSTORMS POSSIBLE. THE STORMS MOVE EASTWARD INTO CENTRAL NORTH DAKOTA BETWEEN MIDNIGHT AND DAYBREAK THURSDAY MORNING. THURSDAY THE ACCOMPANYING SURFACE FRONT IS PROGGED TO BE ORIENTED NORTH-SOUTH ACROSS CENTRAL NORTH DAKOTA...WITH THE BEST CHANCES OF THUNDERSTORMS IN NORTHWEST AND CENTRAL NORTH DAKOTA THURSDAY MORNING...AND SHIFTING TO CENTRAL NORTH DAKOTA THURSDAY AFTERNOON AND INTO THURSDAY EVENING. THE BEST CHANCE FOR SEVERE WEATHER THURSDAY IS IN THE NORTHWEST AND CENTRAL. FRIDAY AND FRIDAY NIGHT LOOKS TO BE THE TIME FRAME FOR WIDESPREAD MODERATE TO HEAVY RAINFALL. CONTINUED UPPER LEVEL ENERGY AND LOW LEVEL MOISTURE WITH A SURFACE LOW BECOMING ESTABLISHED OVER THE CENTRAL PLAINS AND OVERRUNNING PRECIPITATION NORTH OF THE LOW IS FAVORED FOR THE HEAVIEST RAINFALL. WIDESPREAD RAINFALL AMOUNTS OF 1 TO 2 INCHES IS POSSIBLE. THE MODELS CONTINUE TO DEPICT THE UPPER LEVEL LOW MAINTAINING ITS PRESENCE OVER THE ROCKIES WITH SOUTHWEST FLOW OVER NORTH DAKOTA WITH MULTIPLE UPPER LEVEL ENERGY IMPULSES MOVING ACROSS THE STATE IN THE UPPER FLOW. THE MODELS BRING THE UPPER LOW ACROSS THE STATE SUNDAY. PRECIPITATION CHANCES LESSEN MONDAY AND TUESDAY...BUT ZONAL FLOW ALOFT WOULD ALLOW SOME UPPER LEVEL IMPULSES TO SUPPORT SHOWERS AND THUNDERSHOWERS INTO EARLY NEXT WEEK. TEMPERATURES ARE EXPECTED TO BE SEASONABLE THROUGH THE PERIOD...WITH HIGHS IN THE 70S/LOWER 80S...AND LOWS GENERALLY IN THE 50S AND 60S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 624 PM CDT TUE JUN 18 2013 VFR CIGS AND VSBYS EXPECTED THROUGH THE TAF PERIOD. SCT/BKN MID LEVEL CLOUDS WILL DEVELOP AT KDIK OVERNIGHT WITH MAINLY CLEAR SKIES ELSEWHERE. CHANCES FOR SHOWER AND THUNDERSTORMS WILL INCREASE MAINLY AFTER 18Z WEDNESDAY INTO WEDNESDAY NIGHT. A VCTS HAS BEEN ADDED TO MOST AERODROMES WEDNESDAY AFTERNOON. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...WAA LONG TERM...JV AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
624 PM CDT TUE JUN 18 2013 .UPDATE... ISSUED AT 624 PM CDT TUE JUN 18 2013 LATEST WATER VAPOR IMAGERY THIS EVENING SHOWS A MID/UPPER LEVEL DISTURBANCE ROTATING THROUGH CENTRAL NORTH DAKOTA AT THIS TIME. VISIBLE SATELLITE IMAGERY AND SURFACE OBS SHOW SCT MID LEVEL CLOUDS STRETCHING FROM ROSEGLEN TO NEAR DICKINSON...WITH A SCT FAIR WEATHER CUMULUS FIELD ACROSS SOUTH CENTRAL AND EAST CENTRAL NORTH DAKOTA. WITH A H7-H5 RIDGE AXIS ANCHORED FROM WILLISTON TO BISMARCK AND INTO SIOUX FALLS SOUTH DAKOTA TONIGHT...EXPECT A DRY NIGHT ALONG AND EAST OF THE AFOREMENTIONED RIDGE AXIS. ATTENTION THIS EVENING AND OVERNIGHT TURNS TO AN UPSTREAM SHORTWAVE OVER SOUTHEAST WYOMING. THIS IS GENERATING THUNDERSTORMS IN THE HIGHER TERRAIN OF WYOMING...WITH A LARGE MID/HIGH LEVEL CLOUD CANOPY EXPANDING OVER EASTERN WYOMING AND SOUTHEAST MONTANA. THIS IS MOVING NORTHEAST AND WILL SLIDE INTO OUR SOUTHWEST ZONES THIS EVENING. THE LATEST RAP ADVECTS SOME LIGHT PRECIPITATION INTO THE FAR SOUTHWEST ZONES TOWARD 06Z. THE 18Z GFS IS MORE ROBUST IN GENERATING A LARGER SWATH OF LIGHT PRECIPITATION LATE TONIGHT THROUGH MID MORNING WEDNESDAY IN SOUTHWEST NORTH DAKOTA AND JUST GRAZING OUR SOUTH CENTRAL ZONES. HOWEVER OTHER MODELS DELAY THE SHOWERS/THUNDERSTORMS WITH THIS SHORTWAVE UNTIL WEDNESDAY AFTERNOON AND EVENING. WILL AWAIT THE 00Z DATA BEFORE MAKING ANY CHANGES BEYOND TONIGHT. WILL ALSO MONITOR THE CONVECTION APPROACHING THE SOUTHWEST THIS EVENING/OVERNIGHT. ONLY UPDATES THIS EVENING WAS TO HOURLY OBS AND TO INCREASE SKY GRID TRENDS IN THE SOUTHWEST AS MENTIONED ABOVE. THE CLOUD DEBRIS MAY MAKE IT INTO SOUTH CENTRAL NORTH DAKOTA BEFORE SUNRISE WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 324 PM CDT TUE JUN 18 2013 SURFACE TROUGH AND ASSOCIATED WARM FRONTAL BOUNDARY IN EASTERN MONTANA WILL BE THE FOCUS FOR SCATTERED THUNDERSTORMS LATE TONIGHT AND WEDNESDAY AFTERNOON. ANTICIPATE SOME THUNDERSTORMS WILL FIRE OVER THE HIGHER ELEVATION AREAS IN WYOMING/MONTANA/SOUTH DAKOTA AND DRIFT INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT. ON WEDNESDAY ONE LIMITING FACTOR WILL BE A SLOWING EVOLVING ELEVATED MIXED LAYER THAT MAY CAP THUNDERSTORMS OVER WESTERN NORTH DAKOTA WEDNESDAY AFTERNOON. HOWEVER BELIEVE THE INCREASING LOW LEVEL JET AND SIGNIFICANT CAPE VALUES JUSTIFY SCATTERED THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA WEDNESDAY AFTERNOON. WINDS ON WEDNESDAY SHOULD APPROACH BUT REMAIN BELOW WIND ADVISORY CRITERIA SOUTHWEST...PROBABLY 20 TO 35 MPH. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 324 PM CDT TUE JUN 18 2013 THE MAIN FORECAST ISSUE THROUGH THE LONG TERM PERIOD IS CONVECTIVE TRENDS AND POTENTIAL FOR PERIODS OF STRONG TO SEVERE STORMS...SOME ACCOMPANIED BY HEAVY RAINFALL. THE RUNS OF THE GFS/ECMWF ARE IN GENERAL AGREEMENT WITH A SLOWER PROGRESSION OF A LARGE CLOSED UPPER LOW IN THE PACIFIC NORTHWEST EARLY IN THE PERIOD...WITH THE NAM FASTEST IN BRINGING THE MAIN SYNOPTIC FEATURES EASTWARD. HAVE FAVORED THE GFS/EC SOLUTIONS FOR POPS WEDNESDAY NIGHT AND THURSDAY. THERE IS SOME POTENTIAL FOR AN MCS TO CLIP NORTHWEST COUNTIES LATE WEDNESDAY NIGHT INTO THURSDAY MORNING...FUELED BY A 40-50 KT LOW LEVEL JET. THE MAIN DECISION-MAKING ELEMENT WAS WHEN/WHERE THE STRONG MID-LEVEL CAP WOULD INHIBIT CONVECTION...BECAUSE OTHERWISE PLENTY OF CAPE AND SHEARING FOR SEVERE THUNDERSTORMS. WEDNESDAY EVENING THE AXIS OF THE MID-LEVEL CAP OF 10-14C IS SITUATED OVER WYOMING/EASTERN MONTANA AND NUDGING INTO SOUTH DAKOTA AND FAR SOUTHWESTERN NORTH DAKOTA. THE CAP BUILDS DURING THE EVENING NORTHWARD AND EASTWARD ACROSS THE DAKOTAS. AT THIS TIME IT APPEARS THE BEST CHANCE OF SEVERE THUNDERSTORMS BEGINS IN FAR WESTERN NORTH DAKOTA LATE EVENING WEDNESDAY OR EARLY MORNING THURSDAY...WITH SEVERE THUNDERSTORMS POSSIBLE. THE STORMS MOVE EASTWARD INTO CENTRAL NORTH DAKOTA BETWEEN MIDNIGHT AND DAYBREAK THURSDAY MORNING. THURSDAY THE ACCOMPANYING SURFACE FRONT IS PROGGED TO BE ORIENTED NORTH-SOUTH ACROSS CENTRAL NORTH DAKOTA...WITH THE BEST CHANCES OF THUNDERSTORMS IN NORTHWEST AND CENTRAL NORTH DAKOTA THURSDAY MORNING...AND SHIFTING TO CENTRAL NORTH DAKOTA THURSDAY AFTERNOON AND INTO THURSDAY EVENING. THE BEST CHANCE FOR SEVERE WEATHER THURSDAY IS IN THE NORTHWEST AND CENTRAL. FRIDAY AND FRIDAY NIGHT LOOKS TO BE THE TIME FRAME FOR WIDESPREAD MODERATE TO HEAVY RAINFALL. CONTINUED UPPER LEVEL ENERGY AND LOW LEVEL MOISTURE WITH A SURFACE LOW BECOMING ESTABLISHED OVER THE CENTRAL PLAINS AND OVERRUNNING PRECIPITATION NORTH OF THE LOW IS FAVORED FOR THE HEAVIEST RAINFALL. WIDESPREAD RAINFALL AMOUNTS OF 1 TO 2 INCHES IS POSSIBLE. THE MODELS CONTINUE TO DEPICT THE UPPER LEVEL LOW MAINTAINING ITS PRESENCE OVER THE ROCKIES WITH SOUTHWEST FLOW OVER NORTH DAKOTA WITH MULTIPLE UPPER LEVEL ENERGY IMPULSES MOVING ACROSS THE STATE IN THE UPPER FLOW. THE MODELS BRING THE UPPER LOW ACROSS THE STATE SUNDAY. PRECIPITATION CHANCES LESSEN MONDAY AND TUESDAY...BUT ZONAL FLOW ALOFT WOULD ALLOW SOME UPPER LEVEL IMPULSES TO SUPPORT SHOWERS AND THUNDERSHOWERS INTO EARLY NEXT WEEK. TEMPERATURES ARE EXPECTED TO BE SEASONABLE THROUGH THE PERIOD...WITH HIGHS IN THE 70S/LOWER 80S...AND LOWS GENERALLY IN THE 50S AND 60S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 624 PM CDT TUE JUN 18 2013 VFR CIGS AND VSBYS EXPECTED THROUGH THE TAF PERIOD. SCT/BKN MID LEVEL CLOUDS WILL DEVELOP AT KDIK OVERNIGHT WITH MAINLY CLEAR SKIES ELSEWHERE. CHANCES FOR SHOWER AND THUNDERSTORMS WILL INCREASE MAINLY AFTER 18Z WEDNESDAY INTO WEDNESDAY NIGHT. A VCTS HAS BEEN ADDED TO MOST AERODROMES WEDNESDAY AFTERNOON. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...WAA LONG TERM...JV AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
120 PM EDT MON JUN 17 2013 .SYNOPSIS... THE THREAT FOR SHOWERS AND THUNDERSTORMS REMAINS UNTIL A COLD FRONT ACROSS THE UPPER LAKES SINKS SOUTHWARD ACROSS NW PA AND NRN OH TUESDAY. HIGH PRESSURE WILL TAKE ITS PLACE ACROSS THE GREAT LAKES FOR THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HAVE MADE JUST MINOR CHANGES TO THE FORECAST...MAINLY TO CLOUDS. TEMPS SEEM ON TRACK. LATEST GUIDANCE INCLUDING HRRR CONTINUES TO SHOW SHOWERS AND STORMS FIRING OVER LAKE ERIE LATE TODAY AND THEN MOVING INLAND. WILL CONTINUE TO MONITOR. PREVIOUS...STARTING TO GET SOME PATCHY FOG REPORTED IN THE OBS...MOST NOTABLY WHERE THE MOST RAIN FELL YESTERDAY. HAVE ADDED A COUPLE OF HOURS OF PATCHY FOR TO THE FORECAST GRIDS SINCE SOME OF THE VISIBILITIES ARE BELOW A HALF MIL. AREA STABILIZED EARLY THIS MORNING AND WITH NOTHING TO INITIATE A SHOWER/TS...MUCH OF THE FIRST PART OF THE DAY IS EXPECTED TO REMAIN DRY. A FRONTAL BOUNDARY STILL LINGERS JUST NORTH OF THE OHIO BORDER...DIVIDING MID AND UPPER 60 DEWPOINTS TO ITS SOUTH FROM MID 50S DEWPOINTS TO ITS NORTH...BUT IT IS MUCH LESS DEFINED THAN YESTERDAY. 00Z DTX SOUNDING ALSO SHOWS THE RELATIVE DRYING THAT HAS TAKEN PLACE. SHOULD NOT HAVE TO WORRY ABOUT SHRA/TS FOR A GOOD PART OF TODAY. WILL BRING LOW PRECIP CHANCES INTO ERIE PA AFTER 2 PM AND INTO CLE AFTER 5P AS INSTABILITY INCREASES AND FRONTAL ZONE ACROSS MI INTO ONTARIO BEGINS TO DEVELOP SCATTERED CONVECTION. WITH THE GENERAL WESTERLY FLOW...H8 TEMPS CREEP UP A COUPLE OF DEGREES FOR TODAY. SO WILL TACK ON SOME FOR THE HIGHS. THIS WILL PUT NW OHIO SOLIDLY INTO THE MID 80S. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... UPPER TROUGH SHARPENS AND FRONTAL BOUNDARY WILL FINALLY START TO SINK SOUTHWARD. SCATTERED CONVECTION EXPECTED ACROSS MI/ONTARIO FOR THE LATE AFTERNOON AND THAT WILL BEGIN TO SEEP INTO NW PA/NRN OHIO DURING THE EARLY EVENING. WILL MAXIMIZE PRECIP CHANCES THEN IN THE EVENING...TAPERING THEM OVERNIGHT AS WE STABILIZE. FRONT THOUGH WILL BE SLOW TO FLUSH THROUGH THE AREA AND WILL KEEP SOME PRECIP CHANCES INLAND FOR TUESDAY. MILD AGAIN TONIGHT WITH 60S FOR LOWS. TUESDAYS TEMPS WILL REMAIN MILD ACROSS THE SOUTH...BUT THE EFFECTS OF COOLER AND DRIER HIGH PRESSURE ACROSS THE CENTRAL GREAT LAKES WILL BEGIN TO OVERSPREAD THE LAKESHORE. GOOD MODEL CONSENSUS FOR A DRY PERIOD WITH HIGH PRESSURE DOMINANT FOR TUESDAY NIGHT THROUGH THURSDAY NIGHT. HIGHS WILL SLIP BACK SLIGHTLY BELOW NORMAL AND NIGHTS AGAIN WILL GET INTO THE LOWER 50S...WITH A FEW UPPER 40S POSSIBLE. AMPLE SUN AND CLEARING THROUGH THE PERIOD. && .LONG TERM /FRIDAY THROUGH SUNDAY/... GFS AND ECMWF SHOWING A DEVELOPING UPPER RIDGE ACROSS THE SOUTH CENTRAL AND SOUTHEASTERN STATES INTO THE OHIO VALLEY LATE WEEK AND INTO THE WEEKEND WHICH MEANS ON BALANCE...A BIT MORE HEAT IN THE REGION. FRIDAY MODELS SHOW A SURFACE HIGH ACROSS THE GREAT LAKES AND OHIO VALLEY WITH LOW PRESSURE IN KS/NE. GIVEN THE SURFACE HIGH IN THE REGION WENT WITH A DRY FORECAST FOR THE DAY. HUMIDITY WILL BE INCREASING SATURDAY INTO SUNDAY AS THE BOTH THE HIGH AND LOW DRIFT EAST SETTING UP A SOUTHERLY CONVEYOR OUT OF THE GLFMX. SUNDAY THE LOW WILL BE IN THE AREA WITH A WARM FRONT TO OUR EAST AND A TRAILING COLD FRONT WEST. EXPECTING A DECENT SHOT OF AFTERNOON/EVENING SHOWERS/THUNDERSTORMS SATURDAY AND SUNDAY ALTHOUGH WITH THE UPPER HIGH ALSO NOSING INTO THE AREA WILL HOLD POPS TO THE CHANCE CATEGORY. EXPECT HIGHS FROM THE LOW TO MID 80S. && .AVIATION /17Z MONDAY THROUGH FRIDAY/... EXPECT SCATTERED SHOWERS WITH A FEW TSRA THIS AFTERNOON AND EVENING. LEADING EDGE OF WEAK COLD FRONT JUST SOUTH OF THE ERIE LAKESHORE. MODERATE INSTABILITY SOUTH OF THE FRONT WITH CAPES OVER 2,000 J/KG BUT NOT ALOT OF LIFT OR SHEAR. MODELS DEVELOP MORE PREIP AHEAD OF SECONDARY TROUGH ACROSS CENTRAL MICHIGAN THIS AFTERNOON...WHICH MOVES ACROSS NRN OH/NW PA OVERNIGHT. LOW CONFIDENCE HOW WIDESPREAD SHOWERS/TSRA WILL BE OVERNIGHT. .OUTLOOK...MAINLY VFR EXCEPT FOR EARLY MORNING MIST/FOG. && .MARINE... WEAK STATIONARY FRONT ALONG THE SOUTH SHORE OF LAKE ERIE EARLY TODAY WILL BEGIN TO DRIFT SOUTH THROUGH THE MORNING AS ANOTHER COLD FRONT DROPS ACROSS THE CENTRAL LAKES TOWARD THE AREA. THIS SECOND FRONT WILL MOVE ACROSS THE LAKE THIS EVENING. HIGH PRESSURE WILL FOLLOW...BUILDING ACROSS THE CENTRAL GREAT LAKES TUESDAY THROUGH THURSDAY. THE HIGH WILL DRIFT TO NEW ENGLAND ON FRIDAY. EXPECTING SOUTHWEST WINDS ON THE LAKE TODAY AHEAD OF THE COLD FRONT. WINDS WILL TURN NORTH TONIGHT AND THEN NORTHEAST FOR TUESDAY. WITH THE HIGH TO OUR NORTH...WINDS WILL REMAIN FROM THE NORTHEAST FROM TUESDAY THROUGH WEDNESDAY NIGHT OR THURSDAY BEFORE SHIFTING EAST TO SOUTHEAST FRIDAY. NOT EXPECTING WINDS OR WAVES TO GET HIGH ENOUGH FOR A SMALL CRAFT ADVISORY THROUGH THE PERIOD HOWEVER THE NORTHEAST FLOW WILL MAKE A 2 TO 3 FOOT CHOP ON THE CENTRAL AND WEST THIRD NEARSHORE WATERS MIDWEEK. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...OUDEMAN NEAR TERM...KUBINA/OUDEMAN SHORT TERM...OUDEMAN LONG TERM...TK AVIATION...DJB MARINE...TK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
945 AM EDT MON JUN 17 2013 .SYNOPSIS... THE THREAT FOR SHOWERS AND THUNDERSTORMS REMAINS UNTIL A COLD FRONT ACROSS THE UPPER LAKES SINKS SOUTHWARD ACROSS NW PA AND NRN OH TUESDAY. HIGH PRESSURE WILL TAKE ITS PLACE ACROSS THE GREAT LAKES FOR THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HAVE MADE JUST MINOR CHANGES TO THE FORECAST...MAINLY TO CLOUDS. TEMPS SEEM ON TRACK. LATEST GUIDANCE INCLUDING HRRR CONTINUES TO SHOW SHOWERS AND STORMS FIRING OVER LAKE ERIE LATE TODAY AND THEN MOVING INLAND. WILL CONTINUE TO MONITOR. PREVIOUS...STARTING TO GET SOME PATCHY FOG REPORTED IN THE OBS...MOST NOTABLY WHERE THE MOST RAIN FELL YESTERDAY. HAVE ADDED A COUPLE OF HOURS OF PATCHY FOR TO THE FORECAST GRIDS SINCE SOME OF THE VISIBILITIES ARE BELOW A HALF MIL. AREA STABILIZED EARLY THIS MORNING AND WITH NOTHING TO INITIATE A SHOWER/TS...MUCH OF THE FIRST PART OF THE DAY IS EXPECTED TO REMAIN DRY. A FRONTAL BOUNDARY STILL LINGERS JUST NORTH OF THE OHIO BORDER...DIVIDING MID AND UPPER 60 DEWPOINTS TO ITS SOUTH FROM MID 50S DEWPOINTS TO ITS NORTH...BUT IT IS MUCH LESS DEFINED THAN YESTERDAY. 00Z DTX SOUNDING ALSO SHOWS THE RELATIVE DRYING THAT HAS TAKEN PLACE. SHOULD NOT HAVE TO WORRY ABOUT SHRA/TS FOR A GOOD PART OF TODAY. WILL BRING LOW PRECIP CHANCES INTO ERIE PA AFTER 2 PM AND INTO CLE AFTER 5P AS INSTABILITY INCREASES AND FRONTAL ZONE ACROSS MI INTO ONTARIO BEGINS TO DEVELOP SCATTERED CONVECTION. WITH THE GENERAL WESTERLY FLOW...H8 TEMPS CREEP UP A COUPLE OF DEGREES FOR TODAY. SO WILL TACK ON SOME FOR THE HIGHS. THIS WILL PUT NW OHIO SOLIDLY INTO THE MID 80S. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... UPPER TROUGH SHARPENS AND FRONTAL BOUNDARY WILL FINALLY START TO SINK SOUTHWARD. SCATTERED CONVECTION EXPECTED ACROSS MI/ONTARIO FOR THE LATE AFTERNOON AND THAT WILL BEGIN TO SEEP INTO NW PA/NRN OHIO DURING THE EARLY EVENING. WILL MAXIMIZE PRECIP CHANCES THEN IN THE EVENING...TAPERING THEM OVERNIGHT AS WE STABILIZE. FRONT THOUGH WILL BE SLOW TO FLUSH THROUGH THE AREA AND WILL KEEP SOME PRECIP CHANCES INLAND FOR TUESDAY. MILD AGAIN TONIGHT WITH 60S FOR LOWS. TUESDAYS TEMPS WILL REMAIN MILD ACROSS THE SOUTH...BUT THE EFFECTS OF COOLER AND DRIER HIGH PRESSURE ACROSS THE CENTRAL GREAT LAKES WILL BEGIN TO OVERSPREAD THE LAKESHORE. GOOD MODEL CONSENSUS FOR A DRY PERIOD WITH HIGH PRESSURE DOMINANT FOR TUESDAY NIGHT THROUGH THURSDAY NIGHT. HIGHS WILL SLIP BACK SLIGHTLY BELOW NORMAL AND NIGHTS AGAIN WILL GET INTO THE LOWER 50S...WITH A FEW UPPER 40S POSSIBLE. AMPLE SUN AND CLEARING THROUGH THE PERIOD. && .LONG TERM /FRIDAY THROUGH SUNDAY/... GFS AND ECMWF SHOWING A DEVELOPING UPPER RIDGE ACROSS THE SOUTH CENTRAL AND SOUTHEASTERN STATES INTO THE OHIO VALLEY LATE WEEK AND INTO THE WEEKEND WHICH MEANS ON BALANCE...A BIT MORE HEAT IN THE REGION. FRIDAY MODELS SHOW A SURFACE HIGH ACROSS THE GREAT LAKES AND OHIO VALLEY WITH LOW PRESSURE IN KS/NE. GIVEN THE SURFACE HIGH IN THE REGION WENT WITH A DRY FORECAST FOR THE DAY. HUMIDITY WILL BE INCREASING SATURDAY INTO SUNDAY AS THE BOTH THE HIGH AND LOW DRIFT EAST SETTING UP A SOUTHERLY CONVEYOR OUT OF THE GLFMX. SUNDAY THE LOW WILL BE IN THE AREA WITH A WARM FRONT TO OUR EAST AND A TRAILING COLD FRONT WEST. EXPECTING A DECENT SHOT OF AFTERNOON/EVENING SHOWERS/THUNDERSTORMS SATURDAY AND SUNDAY ALTHOUGH WITH THE UPPER HIGH ALSO NOSING INTO THE AREA WILL HOLD POPS TO THE CHANCE CATEGORY. EXPECT HIGHS FROM THE LOW TO MID 80S. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... EARLY MORNING FOG/MIST ACROSS THE AREA WITH MOST LOCATIONS MVFR ALTHOUGH LIFR AT KCAK AND KYNG. FOG/MIST SHOULD BURN OFF QUICKLY THIS MORNING BUT AT LEAST MVFR RESTRICTIONS WILL LIKELY LAST THRU 14Z AT KYNG AND KCAK. FOR THE REMAINDER OF THE DAY EXPECTING VFR CONDITIONS WITH MAINLY SCATTERED CLOUDS BETWEEN 4 AND 6 THOUSAND FEET ALTHOUGH LOCAL CUMULUS SCHEME SUGGESTS A FEW HOURS OF BKN ACROSS THE EAST HALF OF THE AREA. AFTER 00Z EXPECTING INCREASING CLOUDS FROM 10K AND BELOW AS NEXT COLD FRONT APPROACHES FROM THE NORTH. BOUGHT VCSH TO MUCH OF AREA AFTER 04Z ALTHOUGH AN ISOLATED SHOWER NOT OUT OF THE QUESTION EAST HALF BY LATE AFTERNOON. .OUTLOOK...MAINLY VFR EXCEPT FOR EARLY MORNING MIST/FOG. && .MARINE... WEAK STATIONARY FRONT ALONG THE SOUTH SHORE OF LAKE ERIE EARLY TODAY WILL BEGIN TO DRIFT SOUTH THROUGH THE MORNING AS ANOTHER COLD FRONT DROPS ACROSS THE CENTRAL LAKES TOWARD THE AREA. THIS SECOND FRONT WILL MOVE ACROSS THE LAKE THIS EVENING. HIGH PRESSURE WILL FOLLOW...BUILDING ACROSS THE CENTRAL GREAT LAKES TUESDAY THROUGH THURSDAY. THE HIGH WILL DRIFT TO NEW ENGLAND ON FRIDAY. EXPECTING SOUTHWEST WINDS ON THE LAKE TODAY AHEAD OF THE COLD FRONT. WINDS WILL TURN NORTH TONIGHT AND THEN NORTHEAST FOR TUESDAY. WITH THE HIGH TO OUR NORTH...WINDS WILL REMAIN FROM THE NORTHEAST FROM TUESDAY THROUGH WEDNESDAY NIGHT OR THURSDAY BEFORE SHIFTING EAST TO SOUTHEAST FRIDAY. NOT EXPECTING WINDS OR WAVES TO GET HIGH ENOUGH FOR A SMALL CRAFT ADVISORY THROUGH THE PERIOD HOWEVER THE NORTHEAST FLOW WILL MAKE A 2 TO 3 FOOT CHOP ON THE CENTRAL AND WEST THIRD NEARSHORE WATERS MIDWEEK. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...OUDEMAN NEAR TERM...KUBINA/OUDEMAN SHORT TERM...OUDEMAN LONG TERM...TK AVIATION...TK MARINE...TK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1114 PM EDT TUE JUN 18 2013 .SYNOPSIS... THE PERSISTENT JUNE PATTERN OF A BROAD THROUGH OVER THE MID- ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD FROM THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIR MASS WILL FOLLOW IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY. INCREASING HEAT AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE OFFICIAL START OF ASTRONOMICAL SUMMER...AND LAST INTO THE UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 850 MB THE BOUNDARY SINKING SOUTHWARD ACROSS THE LAUREL HIGHLANDS AND SOUTH CENTRAL MOUNTAINS LATE THIS EVENING. RUC13 HAS GOOD HANDLE ON BOUNDARY LOCATION AND NEAR TERM CONVECTION...WHICH IT DISSIPATES BY 08Z FOR MOST. THINK GIVEN THE EXTENT OF ONGOING ACTIVITY AND TRENDS THAT KEEPING POPS UP INTO THE PRE DAWN HOURS NEAR AND SOUTH OF THE TURNPIKE WILL BE PRUDENT AS CONVECTION HAS OUT LIVED ITS PREVIOUS EXPECTATIONS. SUBSIDENCE AND CLEARING WILL COVER THE NORTHERN HALF OF CENTRAL PA BUT WILL BE SLOWER TO ARRIVE ACROSS THE SOUTH GIVEN LATEST IR TRENDS OF ADDITIONAL MID LAYER MOISTURE STREAMING EWD FROM SOUTHERN OHIO...IN ADDITION TO DEBRIS FROM DISSIPATING SHOWER ACTIVITY OVERNIGHT. ALSO...EXPECT SOME FOG IN SOUTHERN VALLEYS AS WELL SINCE WINDS DO GO CALM IN MANY LOCATIONS. MINS WILL BE CHILLY UP NORTH...MIDDLE 40S FOR MOST...WHILE CENTRAL AND SOUTHERN SECTIONS RANGE THROUGH THE 50S. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... LAST SHORTWAVE TO ENHANCE THE TROUGH OVERHEAD WILL RUN OVER THE REGION AROUND SUNRISE...AND THEN THE HEIGHTS START TO RISE STEADILY. SFC HIGH PRESSURE FINALLY PUSHES FAR ENOUGH TO THE SOUTH AND INTO PA TO REMOVE MOST CLOUD COVER AND ALMOST EVERY BIT OF POPS. WILL JUST HANG ONTO A SLIGHT CHC OVER THE HIGHEST TERRAIN OF THE LAURELS/SC MTS WHERE ENOUGH MSTR AND ELEVATED HEATING SURFACES MAY COMBINE TO POP OFF A SHRA OR TWO. TEMPS WILL BE A DEG OR TWO LOWER WED THAN TUES. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... UPPER RIDGE OVER CENTRAL PLAINS WILL BUILD EASTWARD INTO PA WED NIGHT THROUGH SATURDAY...AS 500 MB HEIGHTS RISE TO 588DM. CENTER OF SURFACE HIGH SLIPS SE ACROSS GREAT LAKES AND IS LOCATED OVER CENTRAL PA ON WED NIGHT...SETTING UP IDEAL RADIATIONAL COOLING CONDITIONS. DEWPOINTS WILL STILL BE LINGERING IN THE 50S ACROSS SOUTHERN PA...BUT MUCH LOWER DEWPOINTS NORTH OF I-80 WILL ALLOW TEMPS TO DROP WELL INTO THE 40S. STARTING THU...LLVL S-SWLY RETURN FLOW AROUND SFC HIGH /DRIFTING OFF THE EAST COAST/ WILL BRING A GRADUAL INCREASE IN LLVL MSTR THRU THE END OF THE WORK WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE TSTM ON FRI. OTHERWISE...SUNNY TO MOSTLY SUNNY CONDITIONS WILL PREVAIL AS TEMPS CLIMB TO SEASONAL NORMALS ON THU AND BEGIN A STRING OF ABOVE NORMAL DAYS ON FRIDAY. HEAT AND HUMIDITY CONTINUE TO INCREASE HEADING INTO THE WEEKEND AS HEIGHTS PEAK. BIGGER SURGE OF HIGHER DEWPOINTS SLIDES IN FROM THE WEST AS HEAT CONTINUES TO BUILD...SO A SERIES OF VERY WARM AND HUMID DAYS ARE IN STORE FOR SAT INTO TUES...WITH OVERNIGHT LOWS REMAINING QUITE MILD AS WELL. WITH STAGNANT AIR AND INCREASING HUMIDITY ON BACK SIDE OF SURFACE HIGH...HELD ON TO 20-30 POPS MOST AFTERNOONS - WITH HIGHEST CHANCES OVER WESTERN HIGHER TERRAIN OF ISOLATED DIFFERENTIAL HEATING INITIATED STORMS. PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH FOR MCS ACTIVITY/RIDGE ROLLERS SLIDING DOWN FROM THE NW...THOUGH LATEST MODELS NOT QUITE AS BULLISH ON THAT. EC OVERALL PRODUCING MORE CONVECTION THAN THE GFS...BUT GENERAL AREAS ARE SIMILAR. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... A WEAK SURFACE BOUNDARY CONTINUES TO ACT AS A LOOSE FOCUS FOR SLOW MOVING SHOWERS AND THUNDERSTORMS OVER THE SRN 1/3 OF THE FCST AREA. MOST SITES WILL REMAIN VFR INTO THE OVERNIGHT...BUT SOME MVFR CONDITIONS ARE POSSIBLE FROM JST EASTWARD AS THE SHOWERS MEANDER ABOUT. BEST CHANCE FOR REDUCED CONDITIONS WILL BE WHERE IT RAINED THIS EVENING. ANY EARLY MVFR OVER SRN AREAS WILL IMPROVE SHORTLY AFTER SUNRISE LEADING TO WIDESPREAD VFR WEDNESDAY AS HIGH PRESSURE BUILDS OUT OF THE GR LAKES. HIGH PRESSURE WILL CONTROL THE WX INTO THE WEEKEND. OUTLOOK... THU-FRI...NO SIG WX EXPECTED. SAT-SUN...ISOLD PM TSRA IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DANGELO/DEVOIR SHORT TERM...DANGELO LONG TERM...RXR AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1021 PM EDT TUE JUN 18 2013 .SYNOPSIS... THE PERSISTENT JUNE PATTERN OF A BROAD THROUGH OVER THE MID- ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD FROM THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIR MASS WILL FOLLOW IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY. INCREASING HEAT AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE OFFICIAL START OF ASTRONOMICAL SUMMER...AND LAST INTO THE UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 850 MB THTE BOUNDARY SINKING SOUTHWARD ACROSS THE LAUREL HIGHLANDS AND SOUTH CENTRAL MOUNTAINS LATE THIS EVENING. RUC13 HAS GOOD HANDLE ON BOUNDARY LOCATION AND NEAR TERM CONVECTION...WHICH IT DISSIPATES BY 08Z FOR MOST. THINK GIVEN THE EXTENT OF ONGOING ACTIVITY AND TRENDS THAT KEEPING POPS UP INTO THE PRE DAWN HOURS NEAR AND SOUTH OF THE TURNPIKE WILL BE PRUDENT AS CONVECTION HAS OUT LIVED ITS PREVIOUS EXPECTATIONS. SUBSIDENCE AND CLEARING WILL COVER THE NORTHERN HALF OF CENTRAL PA BUT WILL BE SLOWER TO ARRIVE ACROSS THE SOUTH GIVEN LATEST IR TRENDS OF ADDITIONAL MID LAYER MOISTURE STREAMING EWD FROM SOUTHERN OHIO...IN ADDITION TO DEBRIS FROM DISSIPATING SHOWER ACTIVITY OVERNIGHT. ALSO...EXPECT SOME FOG IN SOUTHERN VALLEYS AS WELL SINCE WINDS DO GO CALM IN MANY LOCATIONS. MINS WILL BE CHILLY UP NORTH...MIDDLE 40S FOR MOST...WHILE CENTRAL AND SOUTHERN SECTIONS RANGE THROUGH THE 50S. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... LAST SHORTWAVE TO ENHANCE THE TROUGH OVERHEAD WILL RUN OVER THE REGION AROUND SUNRISE...AND THEN THE HEIGHTS START TO RISE STEADILY. SFC HIGH PRESSURE FINALLY PUSHES FAR ENOUGH TO THE SOUTH AND INTO PA TO REMOVE MOST CLOUD COVER AND ALMOST EVERY BIT OF POPS. WILL JUST HANG ONTO A SLIGHT CHC OVER THE HIGHEST TERRAIN OF THE LAURELS/SC MTS WHERE ENOUGH MSTR AND ELEVATED HEATING SURFACES MAY COMBINE TO POP OFF A SHRA OR TWO. TEMPS WILL BE A DEG OR TWO LOWER WED THAN TUES. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... UPPER RIDGE OVER CENTRAL PLAINS WILL BUILD EASTWARD INTO PA WED NIGHT THROUGH SATURDAY...AS 500 MB HEIGHTS RISE TO 588DM. CENTER OF SURFACE HIGH SLIPS SE ACROSS GREAT LAKES AND IS LOCATED OVER CENTRAL PA ON WED NIGHT...SETTING UP IDEAL RADIATIONAL COOLING CONDITIONS. DEWPOINTS WILL STILL BE LINGERING IN THE 50S ACROSS SOUTHERN PA...BUT MUCH LOWER DEWPOINTS NORTH OF I-80 WILL ALLOW TEMPS TO DROP WELL INTO THE 40S. STARTING THU...LLVL S-SWLY RETURN FLOW AROUND SFC HIGH /DRIFTING OFF THE EAST COAST/ WILL BRING A GRADUAL INCREASE IN LLVL MSTR THRU THE END OF THE WORK WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE TSTM ON FRI. OTHERWISE...SUNNY TO MOSTLY SUNNY CONDITIONS WILL PREVAIL AS TEMPS CLIMB TO SEASONAL NORMALS ON THU AND BEGIN A STRING OF ABOVE NORMAL DAYS ON FRIDAY. HEAT AND HUMIDITY CONTINUE TO INCREASE HEADING INTO THE WEEKEND AS HEIGHTS PEAK. BIGGER SURGE OF HIGHER DEWPOINTS SLIDES IN FROM THE WEST AS HEAT CONTINUES TO BUILD...SO A SERIES OF VERY WARM AND HUMID DAYS ARE IN STORE FOR SAT INTO TUES...WITH OVERNIGHT LOWS REMAINING QUITE MILD AS WELL. WITH STAGNANT AIR AND INCREASING HUMIDITY ON BACK SIDE OF SURFACE HIGH...HELD ON TO 20-30 POPS MOST AFTERNOONS - WITH HIGHEST CHANCES OVER WESTERN HIGHER TERRAIN OF ISOLATED DIFFERENTIAL HEATING INITIATED STORMS. PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH FOR MCS ACTIVITY/RIDGE ROLLERS SLIDING DOWN FROM THE NW...THOUGH LATEST MODELS NOT QUITE AS BULLISH ON THAT. EC OVERALL PRODUCING MORE CONVECTION THAN THE GFS...BUT GENERAL AREAS ARE SIMILAR. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... A WEAK SURFACE BOUNDARY CONTINUES TO ACT AS A LOOSE FOCUS FOR SLOW MOVING SHOWERS AND THUNDERSTORMS OVER THE SRN HALF OF THE FCST AREA. MOST SITES WILL REMAIN VFR INTO THE OVERNIGHT...BUT SOME MVFR CONDITIONS ARE POSSIBLE FROM JST EASTWARD AS THE SHOWERS MEANDER ABOUT. ANY EARLY MVFR OVER SRN AREAS WILL IMPROVE SHORTLY AFTER SUNRISE LEADING TO WIDESPREAD VFR WEDNESDAY AS HIGH PRESSURE BUILDS OUT OF THE GR LAKES. HIGH PRESSURE WILL CONTROL THE WX INTO THE WEEKEND. OUTLOOK... THU-FRI...NO SIG WX EXPECTED. SAT-SUN...ISOLD PM TSRA IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DANGELO/DEVOIR SHORT TERM...DANGELO LONG TERM...RXR AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1015 PM EDT TUE JUN 18 2013 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION ON WEDNESDAY...BUT WITHOUT ENOUGH MOISTURE TO EXPECT MORE THAN ISOLATED SHOWERS. MOIST EASTERLY FLOW WILL THEN KEEP SOME RAIN CHANCES THRU LATE WEEK MAINLY OVER THE MOUNTAINS. HIGH PRESSURE WILL BUILD OVER THE AREA FOR THE WEEKEND...MAINTAINING A WARM AND MOIST AIRMASS WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH AFTERNOON. && .NEAR TERM /THROUGH WEDNESDAY/... 930 PM UPDATE...DUE TO LARGELY BOUNDARY-PARALLEL SHEAR...CELLS THAT INITIALLY FORMED AROUND SUNSET HAVE TRAINED ROUGHLY ALONG A GREENVILLE TO CHESTER LINE IN CONVERGENT ZONE NEAR THE FRONT. ACTIVITY NOW BEGINNING TO DIMINISH AS INSTABILITY WANES...BUT SOME PRECIP LIKELY TO CONTINUE FOR ANOTHER HOUR OR SO AT LEAST. HOWEVER WITH OUTFLOW PUSHING OUT ACRS GREENVILLE AND SPARTANBURG COUNTIES CAN/T RULE OUT A COUPLE OF ISOLATED SHOWERS FIRING FROM THE SRN PORTIONS OF THOSE COUNTIES SOUTH. NORTH OF THE CURRENT ACTIVITY PRECIP CHANCES ARE TOO SMALL TO MENTION THIS EVENING. STORMS ALONG THE UPSTREAM BOUNDARY OVER KY WOULD TAKE UNTIL AFTER MIDNIGHT TO REACH THE TN/NC BORDER...BUT THEY ARE ALREADY STRUGGLING IN THE MORE STABLE ENVIRONMENT THEY ARE ENTERING...SO DO NOT SEE A NEED TO REFLECT THESE STORMS IN POPS TONIGHT. TEMPS HAVE BEEN ON TRACK SO FAR THIS EVENING AND WILL MAINTAIN GOING LOWS. 730 PM UPDATE...PRECIP ACTIVITY NOW CONFINED TO THE PIEDMONT SHOULD CONTINUE TO MOVE OUT OF THE CWFA WITH FRONT PUSHING INTO THAT AREA. ACTIVITY GENERALLY WEAKENING WITH LOSS OF HEATING ANYWAY. RAP AS WELL AS LOCAL WRF MODEL DO NOT SHOW ANY FURTHER DEVELOPMENT THIS EVENING...AND WINDS ARE DRY AND DOWNSLOPING ANYWAY. STILL DO THINK SOME OF THE REMAINING CU IN EAST TN AND THE MTNS OF WNC WILL REMAIN AS PATCHY STRATUS FOR MUCH OF THE NIGHT...WITH CONVECTIVE DEBRIS SPREADING ACROSS THE SE HALF OF THE CWFA TOO. KEPT PCLDY-MCLDY SKIES OVERNIGHT AS A RESULT. AS OF 230 PM EDT TUESDAY...A BIT OF A TRICKY FCST THIS AFTERNOON AND EARLY EVENING. THE OVERALL PATTERN IS WELL AGREED UPON BY THE MODELS...HOWEVER CONFIDENCE IN THE EVOLUTION OF S/W ENERGY ACROSS THE CWFA IS NOT VERY HIGH DUE TO MODEL DIFFERENCES. THE LATEST RADAR SHOWS AN UNSTABLE AIRMASS TO THE WEST BECOMING INCREASINGLY UNSTABLE INTO THE WRN ZONES. VSBY SAY SHOW GOOD CLEARING AND HEATING TAKING PLACE...BUT IN A DEEPLY MOIST ATMOS SBCAPE VALUES WILL LIKELY REACH ONLY MOD LEVELS. THIS IS A LITTLE EVIDENT IN THE LOW TOP CONV SEEN TO THE WEST. IN ANY REGARD...WILL ANTICIPATE TSTMS DEVELOPING AHEAD OF THE WEAK COLD FRONT AND DEPENDING ON THE STRENGTH OF THE CROSS S/W ENERGY...SOME OF THESE COULD BECOME STRONG TO SEVERE THIS AFTERNOON. THE MAIN THREAT WOULD BE LARGE HAIL AND PERHAPS DAMAGING WINDS AS DRIER AIR WORKS INTO THE MLVLS. EXPECT A WIND SHIFT ACROSS THE MTNS AROUND 00Z AND INTO THE UPSTATE NEAR 05Z. THIS WILL SUPPRESS ANY ACTIVITY TO THE SOUTH WITH A LOWER THETA/E AIRMASS MIXING IN. SOME PATCHY DENSE FG IS POSSIBLE AROUND DAYBREAK IN THE MTN VALLEYS AS THE PGRAD IS NOT REAL TIGHT BEHIND THE FRONT AND BROADENS THROUGH 12Z. A CP HIGH WILL WORK SOUTH INTO THE OH VALLEY TOMORROW AND PUSH A BACKDOOR COLD FRONT INTO THE NRN ZONES BY THE AFTERNOON. THERE IS NOT MUCH MOISTURE AVAILABLE WITH THIS SYSTEM SO WILL EXPECT THE BEST PRECIP CHANCES ACROSS THE MTNS...WHERE AN E/LY UPSLOPE FLOW BRINGS IN ATL MOISTURE. POPS HAVE BEEN HELD TO SLIGHT/CHANCE ACROSS THE MTNS AND SLIGHT ELSEWHERE...WITH MAINLY -SHRA AND PERHAPS A MODERATE THUNDERSTORM OR TWO ACROSS THE FHILLS AND MTNS. MAX TEMPS SHOULD STILL BE A COUPLE DEGREES BELOW NORMAL WITH THE NE/LY SFC FLOW AND AIRMASS MIXING. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 200 PM EDT TUESDAY...THE SHORT TERM WILL BE DOMINATED BY SURFACE HIGH PRESSURE THAT WILL SET UP CAMP OFF THE NEW ENGLAND COAST WHICH WILL REMAIN RIDGED SWD INTO THE SOUTHERN APPALACHIANS THROUGH FRI. THE UPPER AIR PATTERN WILL BE ALMOST INDETERMINATE IN THE DEEP SOUTH WITH VERY WEAK FLOW. THE AREA WILL BE BETWEEN A TROUGH WELL TO THE NE AND AN UPPER RIDGE OVER THE SOUTHERN PLAINS. HENCE...NO SIGNIFCANT UPPER FORCING IS ANTICIPATED. MODEL TIME HEIGHTS INDICATE THAT MOISTURE WILL REMAIN RELATIVELY HIGH IN THE BOUNDARY LAYER WITH DRYING ESSENTAILLY ABOVE 10KFT THROUGH THU NIGHT. HOWEVER...MOISTURE IN THE COLUMN IS FORECAST TO DECREASE ON FRI. HENCE...THE WEATHER SHOULD BE DRIVEN BY MAINLY BY THE LOW LEVEL WIND FLOW AND ANY MECHANICAL LIFT IT MUSTERS...PLUS DIURNAL HEATING. THEREFORE...MAINLY DIURNAL/SCATTERED CONVECTION IS EXPECTED PRIMARILY OVER THE MOUNTAINS...WITH PERHAPS A DOWN TICK IN COVERAGE ON FRI AFTERNOON DUE TO THE DRYER AIR. WITH THE WEAK UPSLOPE FLOW...SOME NOCTURNAL WIDELY SCATTERED SHOWERS WILL REMAIN POSSIBLE OVER THE MOUNTAINS WED/THU NIGHTS. USED AN ALLBLEND APPROACH TO TEMPERATURES WHICH PRODUCED MAX TEMPS ON THU AND FRI ABOUT A CATEGORY BELOW AVERAGE. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 2 PM TUESDAY...THE MAIN FEATURE FOR THE EXTENDED PERIOD IS A RIDGE OF HIGH PRESSURE THAT WILL SET UP OVER THE SOUTHEASTERN CONUS OVER THE WEEKEND AND INTO MONDAY. THE BERMUDA HIGH WILL REMAIN SITUATED OVER THE ATLANTIC OFF THE EAST COAST...SETTING UP A MOIST SOUTHEASTERLY TO SOUTHWESTERLY LOW-LEVEL FLOW REGIME FOR THE REGION. THIS WILL DRIVE MAINLY DIURNAL CONVECTION FOR THE PERIOD...WITH GREATER CHANCE POPS FAVORING THE HIGHER ELEVATIONS EACH AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK. THE PERSISTENT RIDGE WILL ALLOW FOR A SLIGHT WARMING TREND...WITH TEMPS NEAR TO SLIGHTLY ABOVE AVERAGE BY THE END OF THE EXTENDED PERIOD. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... AT KCLT...WINDS WILL SHIFT TO NW QUADRANT THIS EVENING AS FRONTAL BOUNDARY ARRIVES...BUT TIMING TOUGH WITH TSTM ACTIVITY ACRS THE REGION. HAVE SETTLED ON 03Z BASED MAINLY ON GFS MOS AND NAM. SOME SHOWERS PRIOR TO THIS TIME AS WELL THOUGH VSBY SHUD REMAIN VFR. DRIER AIR WILL WORK IN TONIGHT BUT SOME CLOUD COVER WILL LIKELY REMAIN GIVEN AMT OF CONVECTIVE DEBRIS AT THIS TIME JUST BEFORE SUNSET. DOWNSLOPING ON THE NW WINDS WILL LIMIT CLOUD DEVELOPMENT AND GUIDANCE IN DECENT AGREEMENT THAT BKN CIG WILL REMAIN VFR. THIS WILL MIX UP TO 050-060 WED MRNG. ISOLATED -SHRA AROUND THE AREA TMRW BUT NOT WORTHY OF A TAF MENTION. LIGHT NLY WINDS FOLLOWING SHIFT. ELSEWHERE...SHOWER/THUNDER CHANCES VERY SMALL AT TAF SITES THIS EVENING AS DRIER...MORE STABLE AIR PUSHES IN BEHIND A COLD FRONT. SITES THAT HAVE NOT ALREADY SEEN SHIFT TO NW WILL SEE IT BY EARLY WED MRNG. LEFTOVER LOW CU OVER THE MTNS MAY CONGEAL INTO A MORE SOLID DECK THIS EVENING BUT WITH THE DRY AND DOWNSLOPING FLOW CIGS UNLIKELY TO LOWER MUCH...SO KEPT VFR CIGS AT ALL SITES. FAIRLY STRONG SIGNAL FROM GUIDANCE THAT SOME FOG WILL FORM IN THE MTNS/FOOTHILLS. WENT PREVAILING MVFR WITH TEMPO IFR AT KAVL/KHKY. MIDLEVEL CIGS EXPECTED TOMORROW WITH ENUF CU DEVELOPMENT TO EXPECT SOME ISOLATED SHOWERS...BUT WITH COVERAGE TOO LOW TO INCLUDE IN TAFS. OUTLOOK...MOIST EASTERLY FLOW WILL SET UP WED NIGHT LEADING TO LOW STRATUS ACROSS MUCH OF THE AREA THU MORNING WITH RESTRICTIONS LIKELY. CONFIDENCE TABLE... 02-08Z 08-14Z 14-20Z 20-02Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL MED 72% HIGH 86% HIGH 100% HIGH 100% KHKY HIGH 95% HIGH 91% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 95% HIGH 100% HIGH 100% KAND HIGH 95% MED 72% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...WIMBERLEY NEAR TERM...SBK/WIMBERLEY SHORT TERM...LG LONG TERM...VISIN AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
807 PM EDT TUE JUN 18 2013 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION ON WEDNESDAY...BUT WITHOUT ENOUGH MOISTURE TO EXPECT MORE THAN ISOLATED SHOWERS. MOIST EASTERLY FLOW WILL THEN KEEP SOME RAIN CHANCES THRU LATE WEEK MAINLY OVER THE MOUNTAINS. HIGH PRESSURE WILL BUILD OVER THE AREA FOR THE WEEKEND...MAINTAINING A WARM AND MOIST AIRMASS WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH AFTERNOON. && .NEAR TERM /THROUGH WEDNESDAY/... 730 PM UPDATE...PRECIP ACTIVITY NOW CONFINED TO THE PIEDMONT SHOULD CONTINUE TO MOVE OUT OF THE CWFA WITH FRONT PUSHING INTO THAT AREA. ACTIVITY GENERALLY WEAKENING WITH LOSS OF HEATING ANYWAY. RAP AS WELL AS LOCAL WRF MODEL DO NOT SHOW ANY FURTHER DEVELOPMENT THIS EVENING...AND WINDS ARE DRY AND DOWNSLOPING ANYWAY. STILL DO THINK SOME OF THE REMAINING CU IN EAST TN AND THE MTNS OF WNC WILL REMAIN AS PATCHY STRATUS FOR MUCH OF THE NIGHT...WITH CONVECTIVE DEBRIS SPREADING ACROSS THE SE HALF OF THE CWFA TOO. KEPT PCLDY-MCLDY SKIES OVERNIGHT AS A RESULT. AS OF 230 PM EDT TUESDAY...A BIT OF A TRICKY FCST THIS AFTERNOON AND EARLY EVENING. THE OVERALL PATTERN IS WELL AGREED UPON BY THE MODELS...HOWEVER CONFIDENCE IN THE EVOLUTION OF S/W ENERGY ACROSS THE CWFA IS NOT VERY HIGH DUE TO MODEL DIFFERENCES. THE LATEST RADAR SHOWS AN UNSTABLE AIRMASS TO THE WEST BECOMING INCREASINGLY UNSTABLE INTO THE WRN ZONES. VSBY SAY SHOW GOOD CLEARING AND HEATING TAKING PLACE...BUT IN A DEEPLY MOIST ATMOS SBCAPE VALUES WILL LIKELY REACH ONLY MOD LEVELS. THIS IS A LITTLE EVIDENT IN THE LOW TOP CONV SEEN TO THE WEST. IN ANY REGARD...WILL ANTICIPATE TSTMS DEVELOPING AHEAD OF THE WEAK COLD FRONT AND DEPENDING ON THE STRENGTH OF THE CROSS S/W ENERGY...SOME OF THESE COULD BECOME STRONG TO SEVERE THIS AFTERNOON. THE MAIN THREAT WOULD BE LARGE HAIL AND PERHAPS DAMAGING WINDS AS DRIER AIR WORKS INTO THE MLVLS. EXPECT A WIND SHIFT ACROSS THE MTNS AROUND 00Z AND INTO THE UPSTATE NEAR 05Z. THIS WILL SUPPRESS ANY ACTIVITY TO THE SOUTH WITH A LOWER THETA/E AIRMASS MIXING IN. SOME PATCHY DENSE FG IS POSSIBLE AROUND DAYBREAK IN THE MTN VALLEYS AS THE PGRAD IS NOT REAL TIGHT BEHIND THE FRONT AND BROADENS THROUGH 12Z. A CP HIGH WILL WORK SOUTH INTO THE OH VALLEY TOMORROW AND PUSH A BACKDOOR COLD FRONT INTO THE NRN ZONES BY THE AFTERNOON. THERE IS NOT MUCH MOISTURE AVAILABLE WITH THIS SYSTEM SO WILL EXPECT THE BEST PRECIP CHANCES ACROSS THE MTNS...WHERE AN E/LY UPSLOPE FLOW BRINGS IN ATL MOISTURE. POPS HAVE BEEN HELD TO SLIGHT/CHANCE ACROSS THE MTNS AND SLIGHT ELSEWHERE...WITH MAINLY -SHRA AND PERHAPS A MODERATE THUNDERSTORM OR TWO ACROSS THE FHILLS AND MTNS. MAX TEMPS SHOULD STILL BE A COUPLE DEGREES BELOW NORMAL WITH THE NE/LY SFC FLOW AND AIRMASS MIXING. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 200 PM EDT TUESDAY...THE SHORT TERM WILL BE DOMINATED BY SURFACE HIGH PRESSURE THAT WILL SET UP CAMP OFF THE NEW ENGLAND COAST WHICH WILL REMAIN RIDGED SWD INTO THE SOUTHERN APPALACHIANS THROUGH FRI. THE UPPER AIR PATTERN WILL BE ALMOST INDETERMINATE IN THE DEEP SOUTH WITH VERY WEAK FLOW. THE AREA WILL BE BETWEEN A TROUGH WELL TO THE NE AND AN UPPER RIDGE OVER THE SOUTHERN PLAINS. HENCE...NO SIGNIFCANT UPPER FORCING IS ANTICIPATED. MODEL TIME HEIGHTS INDICATE THAT MOISTURE WILL REMAIN RELATIVELY HIGH IN THE BOUNDARY LAYER WITH DRYING ESSENTAILLY ABOVE 10KFT THROUGH THU NIGHT. HOWEVER...MOISTURE IN THE COLUMN IS FORECAST TO DECREASE ON FRI. HENCE...THE WEATHER SHOULD BE DRIVEN BY MAINLY BY THE LOW LEVEL WIND FLOW AND ANY MECHANICAL LIFT IT MUSTERS...PLUS DIURNAL HEATING. THEREFORE...MAINLY DIURNAL/SCATTERED CONVECTION IS EXPECTED PRIMARILY OVER THE MOUNTAINS...WITH PERHAPS A DOWN TICK IN COVERAGE ON FRI AFTERNOON DUE TO THE DRYER AIR. WITH THE WEAK UPSLOPE FLOW...SOME NOCTURNAL WIDELY SCATTERED SHOWERS WILL REMAIN POSSIBLE OVER THE MOUNTAINS WED/THU NIGHTS. USED AN ALLBLEND APPROACH TO TEMPERATURES WHICH PRODUCED MAX TEMPS ON THU AND FRI ABOUT A CATEGORY BELOW AVERAGE. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 2 PM TUESDAY...THE MAIN FEATURE FOR THE EXTENDED PERIOD IS A RIDGE OF HIGH PRESSURE THAT WILL SET UP OVER THE SOUTHEASTERN CONUS OVER THE WEEKEND AND INTO MONDAY. THE BERMUDA HIGH WILL REMAIN SITUATED OVER THE ATLANTIC OFF THE EAST COAST...SETTING UP A MOIST SOUTHEASTERLY TO SOUTHWESTERLY LOW-LEVEL FLOW REGIME FOR THE REGION. THIS WILL DRIVE MAINLY DIURNAL CONVECTION FOR THE PERIOD...WITH GREATER CHANCE POPS FAVORING THE HIGHER ELEVATIONS EACH AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK. THE PERSISTENT RIDGE WILL ALLOW FOR A SLIGHT WARMING TREND...WITH TEMPS NEAR TO SLIGHTLY ABOVE AVERAGE BY THE END OF THE EXTENDED PERIOD. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... AT KCLT...WINDS WILL SHIFT TO NW QUADRANT THIS EVENING AS FRONTAL BOUNDARY ARRIVES...BUT TIMING TOUGH WITH TSTM ACTIVITY ACRS THE REGION. HAVE SETTLED ON 03Z BASED MAINLY ON GFS MOS AND NAM. SOME SHOWERS PRIOR TO THIS TIME AS WELL THOUGH VSBY SHUD REMAIN VFR. DRIER AIR WILL WORK IN TONIGHT BUT SOME CLOUD COVER WILL LIKELY REMAIN GIVEN AMT OF CONVECTIVE DEBRIS AT THIS TIME JUST BEFORE SUNSET. DOWNSLOPING ON THE NW WINDS WILL LIMIT CLOUD DEVELOPMENT AND GUIDANCE IN DECENT AGREEMENT THAT BKN CIG WILL REMAIN VFR. THIS WILL MIX UP TO 050-060 WED MRNG. ISOLATED -SHRA AROUND THE AREA TMRW BUT NOT WORTHY OF A TAF MENTION. LIGHT NLY WINDS FOLLOWING SHIFT. ELSEWHERE...SHOWER/THUNDER CHANCES VERY SMALL AT TAF SITES THIS EVENING AS DRIER...MORE STABLE AIR PUSHES IN BEHIND A COLD FRONT. SITES THAT HAVE NOT ALREADY SEEN SHIFT TO NW WILL SEE IT BY EARLY WED MRNG. LEFTOVER LOW CU OVER THE MTNS MAY CONGEAL INTO A MORE SOLID DECK THIS EVENING BUT WITH THE DRY AND DOWNSLOPING FLOW CIGS UNLIKELY TO LOWER MUCH...SO KEPT VFR CIGS AT ALL SITES. FAIRLY STRONG SIGNAL FROM GUIDANCE THAT SOME FOG WILL FORM IN THE MTNS/FOOTHILLS. WENT PREVAILING MVFR WITH TEMPO IFR AT KAVL/KHKY. MIDLEVEL CIGS EXPECTED TOMORROW WITH ENUF CU DEVELOPMENT TO EXPECT SOME ISOLATED SHOWERS...BUT WITH COVERAGE TOO LOW TO INCLUDE IN TAFS. OUTLOOK...MOIST EASTERLY FLOW WILL SET UP WED NIGHT LEADING TO LOW STRATUS ACROSS MUCH OF THE AREA THU MORNING WITH RESTRICTIONS LIKELY. CONFIDENCE TABLE... 00-06Z 06-12Z 12-18Z 18-24Z KCLT HIGH 94% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 91% HIGH 100% HIGH 100% HIGH 100% KAVL MED 72% HIGH 81% HIGH 96% HIGH 100% KHKY HIGH 94% HIGH 97% HIGH 97% HIGH 100% KGMU HIGH 97% HIGH 88% HIGH 100% HIGH 100% KAND HIGH 100% MED 74% HIGH 87% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...WIMBERLEY NEAR TERM...SBK/WIMBERLEY SHORT TERM...LG LONG TERM...VISIN AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
811 PM CDT TUE JUN 18 2013 .UPDATE... BROKEN LINE OF SHOWERS AND TSTMS ATTEMPTING TO MOVE SOUTHWARD THROUGH WESTERN KY AT THIS TIME. THE ACTIVITY IS STILL SEVERAL COUNTIES NORTH OF THE TN/KY LINE BUT IS MOVING SOUTH. LATEST LAPS DATA SHOWING THAT CAPES DROP FROM 1400 J/KG VCNTY OF STORMS NOW...TO NEAR 600 J/KG ALONG THE TN/KY LINE. 850 MB FLOW IS GENERALLY NORTHERLY WHICH DOES NOT USUALLY CONDONE NOCTURNAL CONVECTIVE SUPPORT. FURTHERMORE...UPPER DIFFLUENCE IS LOOKING MINIMAL. HRRR OF LITTLE SUPPORT AND ONLY GOES OUT TO 03Z FOR NOW. WILL OPT TO MAKE NO CHANGES TO THE FCST AND KEEP THE 20 POPS GOING. WILL REMOVE THOSE POPS IF AND WHEN THE CONVECTION TO THE NORTH COMPLETELY DIES OUT. && .PREV DISCUSSION... /ISSUED 622 PM CDT TUE JUN 18 2013/ AVIATION... NORTHWEST FLOW IN PLACE THIS EVENING. DISTURBANCE ACROSS SOUTHERN IN WILL ATTEMPT TO DROP SOUTHWARD OVERNIGHT. THIS FEATURE SHOULD WEAKEN BUT AN ISOLATED TSTM OR TWO COULD FLIRT WITH CROSSING THE TN/KY BORDER LATE TONIGHT. OTW...SOME LIGHT FOG POSSIBLE TOWARD 12Z. ANOTHER DRY DAY WITH PARTIAL SUNSHINE EXPECTED FOR YOUR WEDNESDAY. PREV DISCUSSION... /ISSUED 228 PM CDT TUE JUN 18 2013/ DISCUSSION... FRONTAL BOUNDARY AND ASSOCIATED CONVECTION NOW WELL SOUTH OF MID STATE WITH SKIES BECOMING PARTLY SUNNY OVER MUCH OF THE CWA AT MID-AFTERNOON. RATHER SHARP SHORT WAVE ACROSS EASTERN IOWA THIS AFTERNOON WILL WORK SOUTHEASTWARD ALONG FRONTAL BOUNDARY THAT CURRENTLY EXTENDS FROM CENTRAL ILLINOIS ACROSS INDIANA INTO OHIO. ALREADY BEGINNING TO SEE SOME CONVECTION FIRING ALONG THAT BOUNDARY. SURFACE BOUNDARY PROGGED TO SINK SOUTHWARD THIS EVENING PRECEDING BY CONVECTION. FRONT WILL BE UNDERGOING FRONTOLYSIS BY THE TIME IT GETS THIS FAR SOUTH. EVEN THOUGH THE FRONT WILL BE WEAKENING I DONT FEEL CONFORTABLE NOT HAVING AT LEAST A MENTION OF ISOLATED THUNDER IN THE FORECAST FOR THE EVENING PERIOD. THERE STILL COULD BE ISOLATED THUNDER ON THE UPPER CUMBERLAND FOR A COUPLE OF HOURS AFTER MIDNIGHT. ALSO...AM EXPECTING LATE NIGHT PATCHY FOG TO DEVELOP. ON WEDNESDAY ANOTHER SHORT WAVE DROPS SOUTHEAST THAT COULD DEVELOP ISOLATED THUNDER ESPECIALLY DURING THE AFTERNOON AND EARLY EVENING. THURSDAY THROUGH THE WEEKEND WILL TURN OUT QUITE SUMMER-LIKE... RIGHT ON CUE WITH THE SUMMER SOLSTICE WHICH OCCURS FRIDAY JUNE 21ST AT 12:04 AM CDT. PLAINS UPPER RIDGE WILL REMAIN IN PLACE INTO THE WEEKEND WITH MID STATE REMAINING IN NORTHWEST FLOW. THIS MEANS A THUNDERSTORM CHANCE PRETTY MUCH EACH DAY. BOYD && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1218 AM CDT MON JUN 17 2013 .UPDATE... UPDATED FOR 06Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 910 PM CDT SUN JUN 16 2013/ DISCUSSION...WATER VAPOR SATELLITE/UPPER AIR PROFILERS/WSR-88D VAD WIND PROFILES INDICATE SEVERAL 500 MB MID LEVEL SHORTWAVES EMBEDDED WITHIN NEARLY ZONAL FLOW ALOFT ACROSS THE CENTRAL/SOUTHERN PLAINS AND MIDDLE/LOWER MISSISSIPPI VALLEYS THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE MID SOUTH DISSIPATED A FEW HOURS AGO WITH THE MOST OF THE CONVECTIVE ACTIVITY THIS EVENING OCCURRING ACROSS PORTIONS OF OKLAHOMA...MISSOURI...ARKANSAS...AND TEXAS. TEMPERATURES AS OF 8 PM CDT RANGE FROM THE LOWER TO MIDDLE 80S WEST OF THE MISSISSIPPI RIVER...AND 70S TO LOWER 80S EAST. SHOWER AND THUNDERSTORM POTENTIAL FOR THE REMAINDER OF THE NIGHT REMAINS THE PREDOMINANT FORECAST CHALLENGE. 00Z KLZK UPPER AIR SOUNDING STILL REMAINS QUITE UNSTABLE WITH SURFACE BASED CAPE VALUES AROUND 3200 J/KG...LI/S AROUND -8...AND VERY LITTLE CONVECTIVE INHIBITION. INSTABILITY AT KJAN REMAINS SIMILAR WITH MUCH MORE LOW LEVEL MOISTURE PRESENT THAN LZK. MEANWHILE...INSTABILITY IS LOWER AT OHX THIS EVENING. 18Z MODELS AND THE 00Z NAM ARE NOT HANDLING THE CURRENT CONVECTIVE ACTIVITY PARTICULARLY WELL. THE LATEST RAPID REFRESH /HRRR/ INDICATES THE BEST POTENTIAL FOR SHOWER/THUNDERSTORM ACTIVITY WILL REMAIN MAINLY ALONG AND WEST OF THE MISSISSIPPI RIVER OVERNIGHT. AN ISOLATED STRONG TO PERHAPS SEVERE THUNDERSTORM MAY BE POSSIBLE FOR THE NEXT FEW HOURS MAINLY WEST OF THE MISSISSIPPI RIVER. OTHERWISE...OVERALL POTENTIAL REMAINS LOW AT THIS TIME. BASED ON THE LATEST TRENDS WILL LOWER POPS SLIGHTLY ACROSS EASTERN SECTIONS OF THE FORECAST AREA AND KEEP ONGOING CHANCE POPS ALONG AND WEST OF THE MISSISSIPPI RIVER. WILL ALSO ADJUST TEMPERATURES...CLOUD COVER...AND ALL OTHER ELEMENTS AS NEEDED TO ACCOUNT FOR SHORT TERM TRENDS. OTHERWISE...FORECAST OVERALL IS IN GOOD SHAPE. UPDATED GRIDS WILL BE AVAILABLE SHORTLY. CJC && .PREV DISCUSSION... /ISSUED 620 PM CDT SUN JUN 16 2013/ UPDATE...AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 318 PM CDT SUN JUN 16 2013/ DISCUSSION... WET PATTERN SETTING OVER THE MIDSOUTH OVER THE NEXT COUPLE OF DAYS AS A COLD FRONT AND SEVERAL SHORTWAVES MOVE INTO THE REGION. TONIGHT...VERY LOW CONFIDENCE ON WHAT WILL HAPPEN AS MODELS DID NOT INITIALIZE VERY WELL. ABUNDANCE OF CLOUD COVER OVER THE REGION HAS KEPT THE ATMOSPHERE MORE STABLE THAN WHAT THE MODELS WERE INDICATING. THUS THE NAM AND RAP MODELS SHOWED NUMEROUS SHOWERS AND THUNDERSTORMS DEVELOPING THIS AFTERNOON INTO THE EVENING HOURS DUE TO THE COMBINATION OF PEAK HEATING AND THE EXPECTED UNSTABLE ATMOSPHERE. THIS IS NOT THE CASE AT LEAST SO FAR. HOWEVER...WITHIN THE LAST 45 MINUTES A THUNDERSTORM HAS DEVELOPED OVER PANOLA COUNTY. THE NAM AND RAP SHOWED WHATEVER ACTIVITY DEVELOPED DYING OUT AFTER SUNSET. MEANWHILE...OTHER MODELS LIKE THE HRRR SHOWED DEVELOPMENT ALONG AND AHEAD OF AN OUTFLOW BOUNDARY WHICH IS DRAPED ACROSS SOUTHERN MISSOURI. BEGINNING TO SEE DEVELOPMENT OCCUR ALONG THE BOUNDARY BUT NOTHING AHEAD OF IT YET OTHER THAN A FEW SHOWERS. THE HRRR BRINGS THE ACTIVITY INTO NORTHERN PORTIONS OF THE MIDSOUTH THIS EVENING AND THEN DISSIPATES IT BY MIDNIGHT. IN ADDITION...THE GFS AND ECMWF SHOWED LITTLE ACTIVITY OCCURRING THIS EVENING. IN FACT...THE ECMWF SHOWED LITTLE ACTIVITY THE ENTIRE NIGHT. HOWEVER...THE GFS AND THE NAM BOTH SHOW REDEVELOPMENT OF SHOWERS AFTER MIDNIGHT...POSSIBLY DUE TO A WEAK LOW LEVEL JET. WITH SUCH A WIDE RANGE OF SCENARIOS...HAVE KEPT 40 POPS ACROSS FROM THE TENNESSEE/MISSISSIPPI LINE NORTHWARD MAINLY DUE TO THE CONVECTION YOU SEE BEGINNING TO DEVELOP ALONG THE OLD OUTFLOW BOUNDARY. THINK THIS CONVECTION WILL PUSH DOWN INTO NORTHEAST ARKANSAS...THE MISSOURI BOOTHEEL...AND NORTHWEST TENNESSEE. MAY ALSO SEE A FEW MORE POP UP DIURNAL THUNDERSTORMS ACROSS NORTH MISSISSIPPI. DON/T KNOW IF ANY STORM WILL BE SEVERE BUT WILL KEEP THE STRONG TO SEVERE WORDING IN THE HWO FOR NOW. LOWS WILL BE IN THE LOWER TO MID 70S. MONDAY...A STRONGER SHORTWAVE WILL MOVE INTO THE REGION AS A COLD FRONT SLIDES SOUTH INTO THE CWA. THE COMBINATION OF THE TWO SHOULD PRODUCE NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE CWA. CLOUD COVER MAY AFFECT INSTABILITY LIKE IT DID TODAY BUT CAN/T RULE OUT A FEW STORMS BECOMING STRONG TO SEVERE. ISOLATED HEAVY RAINFALL UNDERNEATH SLOW MOVING STORMS MAY BE A BIGGEST ISSUE WITH ANY THUNDERSTORMS THAT OCCUR TOMORROW. THE ACTIVITY WILL CONTINUE INTO MONDAY NIGHT AND TUESDAY AS THE COLD FRONT SLIDES SOUTHWARD. HIGHS ON MONDAY AND TUESDAY WILL BE IN THE 80S DUE TO THE CLOUD COVER AND AMOUNT OF CONVECTION AROUND. TUESDAY NIGHT INTO WEDNESDAY....THE GFS SLIDES THE FRONT SOUTH OF THE CWA WHILE THE ECMWF CONTINUES TO HOLD THE FRONT UP OVER NORTH MISSISSIPPI. BOTH THE GFS/ECMWF ARE CONSISTENT WITH THEIR SOLUTIONS AND ITS REALLY ANYBODY/S GUESS WHICH IS CORRECT. FOR NOW WILL CONTINUE WITH CURRENT FORECAST WHICH LEANS TOWARD THE GFS. THURSDAY AND FRIDAY...UPPER RIDGE BEGINS TO START MOVING BACK INTO THE AREA FROM THE WEST. SOME DIURNAL CONVECTION COULD OCCUR ON THURSDAY. OTHERWISE...WARMER TEMPERATURES WILL RETURN WITH HIGHS IN THE UPPER 80S TO LOWER 90S. NEXT WEEKEND...HOT AND DRY CONDITIONS ARE EXPECTED AS THE UPPER RIDGE WILL BE CENTERED OVER THE MIDSOUTH. HIGHS WILL BE IN THE LOWER TO MID 90S WITH LOWS IN THE 70S. KRM && .AVIATION... 06Z TAF CYCLE VFR CONDITIONS WILL PREVAIL THROUGH THIS TAF PERIOD. ONLY ONE STORM COMPLEX IS OF CONCERN ON THE RADAR...IT MAY IMPACT MEM BETWEEN 09 AND 11Z...BUT CONFIDENCE IS LOW THAT IT WILL -1 STAY TOGETHER...AND -2 MAINTAIN ITS EASTWARD TRACK. IT IT DOES AN HOUR OR TWO OF MVFR TO IFR VIS CAN BE EXPECTED ALONG WITH TEMPORARY GUSTY WINDS...MOST LIKELY FROM THE WEST. REMOVED MENTION OF TS AT ALL OTHER SITES FOR THE REMAINDER OF THE NIGHT. WINDS WILL BE LIGHT AND VARIABLE DUE TO MULTIPLE OUTFLOW BOUNDARIES ACROSS THE MIDSOUTH...BUT GENERALLY FROM THE SOUTH. TOMORROW...THUNDERSTORM COVERAGE WILL INCREASE AGAIN BY MIDDAY. INCLUDED VCTS AT ALL SITES. INDIVIDUAL STORMS WILL REDUCE VIS AND MAY RESULT IN STRONG GUSTY WINDS...BUT PREVAILING CONDITIONS WILL REMAIN VFR. COVERAGE AND INTENSITY OF STORMS SHOULD DIMINISH AFTER SUNSET. && .PRELIMINARY POINT TEMPS/POPS... MEM 71 86 71 88 / 80 40 10 10 MKL 69 85 64 87 / 80 30 10 10 JBR 69 87 67 87 / 40 10 10 10 TUP 72 84 68 88 / 70 60 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1140 PM CDT SUN JUN 16 2013 .UPDATE... 06Z TAF DISCUSSION. && .AVIATION... RADAR INDICATES ONLY A COUPLE ISOLATED SHOWERS REMAIN OVER EASTERN ZONES NEAR CSV. ALTHOUGH SOME REDEVELOPMENT OF -SHRA/-TSRA IS POSSIBLE OVERNIGHT...ACTIVITY IS EXPECTED TO REMAIN SOUTH OF AIRPORTS AND WILL REMOVE PRECIP MENTION FOR TONIGHT. WIDESPREAD CIRRUS AND MID LEVEL CLOUD COVER PUSHING ACROSS THE MID STATE WILL PREVENT ANY SIGNIFICANT FOG FORMATION...BUT SOME MVFR/IFR VIS RESTRICTIONS ARE EXPECTED AT CKV/CSV OVERNIGHT. SCT CUMULUS TO REDEVELOP ONCE AGAIN ON MONDAY WITH VCTS BY AFTERNOON AT ALL AIRPORTS. LIGHT SOUTH TO SOUTHWEST WINDS ARE ANTICIPATED THROUGHOUT THE TAF PERIOD. SHAMBURGER && .PREV DISCUSSION... /ISSUED 1116 PM CDT SUN JUN 16 2013/ UPDATE... CONDITIONS CONTINUE TO QUIET DOWN ACROSS THE MID STATE. OVERALL TREND SHOULD REMAIN THAT WAY AS NVA INDICATED THROUGH THE OVERNIGHT. ORGANIZED DISTURBANCE UPSTREAM ACROSS WESTERN AR WILL ATTEMPT TO MOVE EAST BUT IS EXPECTED TO WEAKEN. HOWEVER...ADDITIONAL MID/HIGH LEVEL CLOUD COVER SHOULD MOVE ACROSS THE AREA LATER TONIGHT. HRRR STILL SHOWS SOME REDEVELOPMENT ACROSS SOUTHERN MIDDLE TN TOWARD 12Z. WILL THEREFORE NOT REMOVE POPS ENTIRELY. FOR THE GRID UPDATE...WILL LOWER POPS AREA WIDE AND INTRODUCE SOME PARTIAL CLEARING OVER WESTERN ZONES FOR THE NEXT FEW HOURS. UPDATE OUT SHORTLY. PREV DISCUSSION... /ISSUED 921 PM CDT SUN JUN 16 2013/ UPDATE... RADAR COVERAGE HAS DECREASED MARKEDLY ACROSS NORTHERN AND WESTERN AREAS OF THE MID STATE. MODELS LEAN TOWARD A DECREASE IN MOISTURE LEVELS ACROSS NORTHERN AREAS. FURTHERMORE...LATEST MODEL SOLUTIONS SHOWING NVA TOWARD 12Z ACROSS THE NORTH. BUT...LATEST HRRR SOLUTION TENDS TO REGENERATE CONVECTION ACROSS CENTRAL AND SOUTHERN AREAS TOWARD 12Z AS SOME UPPER DIVERGENCE REENTERS THE PICTURE TOWARD 12Z. FOR THE UPDATE...WILL CUT POPS TO 30 PERCENT ACROSS THE NORTH...BUT WILL KEEP THE 40%-50% FOR MUCH OF THE REMAINDER OF THE MID STATE. UPDATE OUT SHORTLY. PREV DISCUSSION... /ISSUED 721 PM CDT SUN JUN 16 2013/ UPDATE... 00Z TAF DISCUSSION. AVIATION... RADAR INDICATES SCATTERED -TSRA CONTINUE OVER SOUTHERN MIDDLE TENNESSEE WITH A FEW -SHRA OVER NORTHERN AREAS. WILL CONTINUE MENTION OF VCTS FOR THE EVENING HOURS FOR ALL AIRPORTS...BUT LACK OF -TSRA OVER NORTHERN ZONES NO LONGER WARRANT TEMPO GROUPS AND MAY PROMPT REMOVAL OF VCTS FROM TAFS AS WELL. CONVECTION IS EXPECTED TO DISSIPATE ACROSS MOST OF THE AREA OVERNIGHT. WIDESPREAD CIRRUS AND MID LEVEL CLOUD COVER WILL LIKELY PREVENT ANY SIGNIFICANT FOG FORMATION BUT SOME MVFR VIS RESTRICTIONS ARE POSSIBLE AT CKV/CSV AROUND SUNRISE. SCT CUMULUS TO DEVELOP ONCE AGAIN MONDAY MORNING WITH CONVECTION REDEVELOPING DURING THE DAY...WITH MORE VCTS BY AFTERNOON IF NOT SOONER. SHAMBURGER PREV DISCUSSION... /ISSUED 630 PM CDT SUN JUN 16 2013/ CURRENTLY...SCATTERED CONVECTION SOUTH...MINIMAL ACTIVITY NORTH BUT BETTER COVERAGE NORTHWARD INTO KY. SEMI ACTIVE PATTERN WITHIN THE WESTERLIES ALOFT AS MINI DISTURBANCES ARE MOVING EASTWARD WITHIN THE FLOW. LATEST LAPS DATA SHOWING APPRECIABLE SURFACE BASE CAPES WITH MAXIMUMS LOCATED ACROSS LEWIS COUNTY...AND ALSO OUR FAR NW AND THE NORTHERN PLATEAU. THUS...THROUGH THIS EVENING STRONG STORMS WILL BE AN ONGOING POSSIBILITY. NOT SEEING MUCH OVERNIGHT DIVERGENCE SO NOT LOOKING FOR WIDESPREAD RAINFALL TO DEVELOP ALTHOUGH MRH LEVELS DO INCREASE SLIGHTLY THROUGH 12Z ACROSS OUR SOUTHERN COUNTIES. PREV DISCUSSION... /ISSUED 317 PM CDT SUN JUN 16 2013/ DISCUSSION... GENERAL TREND FOR THE WEEK AHEAD WILL FEATURE A BUILDING H5 RIDGE TO OUR WEST WITH OCCASIONAL WEAK SHORT WAVES IN THE NORTHWEST FLOW ALOFT. BEST CHANCE OF RAIN WILL BE MONDAY INTO EARLY TUESDAY. AFTER A WEAK COLD FRONTAL PASSAGE ON TUESDAY...EXPECT MAX TEMPS TO INCREASE TO 85 TO 90 AREA WIDE MID/LATE WEEK AS UPPER LEVEL RIDGE EDGES CLOSER TO MIDDLE TN. THIS AFTERNOON/S TEMPS WERE NEAR SATURDAY/S BUT DEW POINTS WERE UP 5 TO 10 DEGREES DUE TO SOUTH FLOW ACROSS THE REGION BEHIND DEPARTED SFC HIGH PRESSURE. INSTABILITY IS GREATER TODAY BUT STORMS HAVE BEEN SLOW TO FIRE PARTLY DUE TO EXTENSIVE MID/HIGH CLOUDS STREAMING IN FROM THE WEST. STILL THINK SOME STORMS WILL DEVELOP OVER MIDDLE TN NEXT COUPLE HOURS...AND ADDITIONAL STORMS SHOULD MOVE IN FROM THE WEST WITH THE APPROACHING WEAK SHORT WAVE. ABOVE AVERAGE CHANCE OF STORMS MONDAY/TUESDAY AS ANOTHER WEAK SHORT WAVE MOVES INTO THE REGION. BEST CHANCE SHOULD BE LATE MONDAY INTO EARLY TUESDAY AS WAVE MOVES ACROSS THE AREA AND A WEAK COLD FRONT MOVES IN FROM THE NORTH. NOT A STRONG PUSH BEHIND THIS FRONT BUT EXPECT/HOPE IT TO MOVE JUST SOUTH OF MIDDLE TN TUESDAY NIGHT. NOT MUCH PRECIP EXPECTED WED/THURS AS MOISTURE SHOULD DECREASE BEHIND THE FRONT. HOWEVER...LOW LEVEL MOISTURE WILL INCREASE AGAIN BY FRIDAY AS SFC HIGH SLIDES TO THE EAST. POTENTIAL FOR STORMS FRIDAY THROUGH NEXT WEEKEND SHOULD BE LIMITED BY INCREASINGLY STRONG HIGH PRESSURE ALOFT. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1116 PM CDT SUN JUN 16 2013 .UPDATE... CONDITIONS CONTINUE TO QUIET DOWN ACROSS THE MID STATE. OVERALL TREND SHOULD REMAIN THAT WAY AS NVA INDICATED THROUGH THE OVERNIGHT. ORGANIZED DISTURBANCE UPSTREAM ACROSS WESTERN AR WILL ATTEMPT TO MOVE EAST BUT IS EXPECTED TO WEAKEN. HOWEVER...ADDITIONAL MID/HIGH LEVEL CLOUD COVER SHOULD MOVE ACROSS THE AREA LATER TONIGHT. HRRR STILL SHOWS SOME REDEVELOPMENT ACROSS SOUTHERN MIDDLE TN TOWARD 12Z. WILL THEREFORE NOT REMOVE POPS ENTIRELY. FOR THE GRID UPDATE...WILL LOWER POPS AREA WIDE AND INTRODUCE SOME PARTIAL CLEARING OVER WESTERN ZONES FOR THE NEXT FEW HOURS. UPDATE OUT SHORTLY. && .PREV DISCUSSION... /ISSUED 921 PM CDT SUN JUN 16 2013/ UPDATE... RADAR COVERAGE HAS DECREASED MARKEDLY ACROSS NORTHERN AND WESTERN AREAS OF THE MID STATE. MODELS LEAN TOWARD A DECREASE IN MOISTURE LEVELS ACROSS NORTHERN AREAS. FURTHERMORE...LATEST MODEL SOLUTIONS SHOWING NVA TOWARD 12Z ACROSS THE NORTH. BUT...LATEST HRRR SOLUTION TENDS TO REGENERATE CONVECTION ACROSS CENTRAL AND SOUTHERN AREAS TOWARD 12Z AS SOME UPPER DIVERGENCE REENTERS THE PICTURE TOWARD 12Z. FOR THE UPDATE...WILL CUT POPS TO 30 PERCENT ACROSS THE NORTH...BUT WILL KEEP THE 40%-50% FOR MUCH OF THE REMAINDER OF THE MID STATE. UPDATE OUT SHORTLY. PREV DISCUSSION... /ISSUED 721 PM CDT SUN JUN 16 2013/ UPDATE... 00Z TAF DISCUSSION. AVIATION... RADAR INDICATES SCATTERED -TSRA CONTINUE OVER SOUTHERN MIDDLE TENNESSEE WITH A FEW -SHRA OVER NORTHERN AREAS. WILL CONTINUE MENTION OF VCTS FOR THE EVENING HOURS FOR ALL AIRPORTS...BUT LACK OF -TSRA OVER NORTHERN ZONES NO LONGER WARRANT TEMPO GROUPS AND MAY PROMPT REMOVAL OF VCTS FROM TAFS AS WELL. CONVECTION IS EXPECTED TO DISSIPATE ACROSS MOST OF THE AREA OVERNIGHT. WIDESPREAD CIRRUS AND MID LEVEL CLOUD COVER WILL LIKELY PREVENT ANY SIGNIFICANT FOG FORMATION BUT SOME MVFR VIS RESTRICTIONS ARE POSSIBLE AT CKV/CSV AROUND SUNRISE. SCT CUMULUS TO DEVELOP ONCE AGAIN MONDAY MORNING WITH CONVECTION REDEVELOPING DURING THE DAY...WITH MORE VCTS BY AFTERNOON IF NOT SOONER. SHAMBURGER PREV DISCUSSION... /ISSUED 630 PM CDT SUN JUN 16 2013/ MESOSCALE UPDATE... CURRENTLY...SCATTERED CONVECTION SOUTH...MINIMAL ACTIVITY NORTH BUT BETTER COVERAGE NORTHWARD INTO KY. SEMI ACTIVE PATTERN WITHIN THE WESTERLIES ALOFT AS MINI DISTURBANCES ARE MOVING EASTWARD WITHIN THE FLOW. LATEST LAPS DATA SHOWING APPRECIABLE SURFACE BASE CAPES WITH MAXIMUMS LOCATED ACROSS LEWIS COUNTY...AND ALSO OUR FAR NW AND THE NORTHERN PLATEAU. THUS...THROUGH THIS EVENING STRONG STORMS WILL BE AN ONGOING POSSIBILITY. NOT SEEING MUCH OVERNIGHT DIVERGENCE SO NOT LOOKING FOR WIDESPREAD RAINFALL TO DEVELOP ALTHOUGH MRH LEVELS DO INCREASE SLIGHTLY THROUGH 12Z ACROSS OUR SOUTHERN COUNTIES. PREV DISCUSSION... /ISSUED 317 PM CDT SUN JUN 16 2013/ DISCUSSION... GENERAL TREND FOR THE WEEK AHEAD WILL FEATURE A BUILDING H5 RIDGE TO OUR WEST WITH OCCASIONAL WEAK SHORT WAVES IN THE NORTHWEST FLOW ALOFT. BEST CHANCE OF RAIN WILL BE MONDAY INTO EARLY TUESDAY. AFTER A WEAK COLD FRONTAL PASSAGE ON TUESDAY...EXPECT MAX TEMPS TO INCREASE TO 85 TO 90 AREA WIDE MID/LATE WEEK AS UPPER LEVEL RIDGE EDGES CLOSER TO MIDDLE TN. THIS AFTERNOON/S TEMPS WERE NEAR SATURDAY/S BUT DEW POINTS WERE UP 5 TO 10 DEGREES DUE TO SOUTH FLOW ACROSS THE REGION BEHIND DEPARTED SFC HIGH PRESSURE. INSTABILITY IS GREATER TODAY BUT STORMS HAVE BEEN SLOW TO FIRE PARTLY DUE TO EXTENSIVE MID/HIGH CLOUDS STREAMING IN FROM THE WEST. STILL THINK SOME STORMS WILL DEVELOP OVER MIDDLE TN NEXT COUPLE HOURS...AND ADDITIONAL STORMS SHOULD MOVE IN FROM THE WEST WITH THE APPROACHING WEAK SHORT WAVE. ABOVE AVERAGE CHANCE OF STORMS MONDAY/TUESDAY AS ANOTHER WEAK SHORT WAVE MOVES INTO THE REGION. BEST CHANCE SHOULD BE LATE MONDAY INTO EARLY TUESDAY AS WAVE MOVES ACROSS THE AREA AND A WEAK COLD FRONT MOVES IN FROM THE NORTH. NOT A STRONG PUSH BEHIND THIS FRONT BUT EXPECT/HOPE IT TO MOVE JUST SOUTH OF MIDDLE TN TUESDAY NIGHT. NOT MUCH PRECIP EXPECTED WED/THURS AS MOISTURE SHOULD DECREASE BEHIND THE FRONT. HOWEVER...LOW LEVEL MOISTURE WILL INCREASE AGAIN BY FRIDAY AS SFC HIGH SLIDES TO THE EAST. POTENTIAL FOR STORMS FRIDAY THROUGH NEXT WEEKEND SHOULD BE LIMITED BY INCREASINGLY STRONG HIGH PRESSURE ALOFT. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS AMARILLO TX
412 PM CDT MON JUN 17 2013 .UPDATE... SEVERE THUNDERSTORM WATCH NUMBER 323 HAS BEEN ISSUED FOR THE CENTRAL AND WESTERN TEXAS AND OKLAHOMA PANHANDLES UNTIL 11 PM. PRIMARY THREATS WILL BE LARGE HAIL AND DAMAGING WIND. DUE TO SATURATED SOILS AND HEAVY RAIN POTENTIAL...THERE WILL ALSO BE A LOCALIZED AND FLASH FLOODING THREAT. UPDATED TEXT PRODUCTS HAVE BEEN ISSUED. && .PREV DISCUSSION... /ISSUED 312 PM CDT MON JUN 17 2013/ DISCUSSION... TODAY AND TOMORROW REMAIN ACTIVE DAYS FOR THE TEXAS AND OKLAHOMA PANHANDLES. TEMPERATURES WERE SLOW TO COME UP THIS MORNING BUT HAVE BEGUN TO QUICKLY RISE ACROSS THE AREA. THERE WAS SOME CONCERN THAT THE SLOW HEATING WOULD DELAY INITIATION OF STORMS THIS AFTERNOON HOWEVER VISIBLE SATELLITE IMAGERY IS SHOWING A MILD CU FIELD DEVELOPING ACROSS THE EASTERN HALF OF THE PANHANDLES. ALSO CONVECTION OVER THE NEW MEXICO MOUNTAINS HAS INITIATED ONLY ABOUT A HOUR BEHIND WHAT WAS SHOWN IN THE 14Z RUC HRRR. AS SUCH THE PREVIOUS FORECAST SEVERE THREAT START TIME OF 6 PM REMAINS REALISTIC. WILL PAY CLOSE ATTENTION TO THE DEVELOPING CONVECTION ALONG THE RED RIVER AS IT COULD BACK BUILD ALONG A SOUTHWARD PROGRESSING COLD FRONT INTO COLLINGSWORTH COUNTY PRIOR TO 6 PM. THE SEVERE THREAT WILL LAST UNTIL 2-3AM TUESDAY WHEN STRONG CAPPING WILL SETUP HOWEVER...PRECIPITATION MAY LAST WELL PAST 3 AM. SPC MESO ANALYSIS HAS SHOWN A CONTINUAL DECREASING TREND OF CIN VALUES ACROSS THE WESTERN TEXAS AND OKLAHOMA PANHANDLES DURING THE SAME TIME SHOWING AN INCREASE OF SBCAPE VALUES. FORECAST SBCAPE VALUES OF 1500-2500 J/KG WITH DEEP LAYER SHEAR OF 35-40 KT CONTINUE SUPPORT LARGE HAIL AND DAMAGING WIND AS THE PRIMARY SEVERE HAZARDS. GIVEN SLOW STORM MOTIONS OF 15 TO 20 KTS...MOIST SOILS FROM PREVIOUS RAINS...AND PWAT VALUES NEAR AN INCH WILL KEEP LOCALIZED AND FLASH FLOODING AS A CONCERN WITH THESE STORMS. TOMORROW MODELS CONTINUE TO ADVERTISE REDEVELOPMENT OF STORMS ACROSS THE PANHANDLE. CAPE VALUES OF 1000-2000 J/KG AND DEEP SHEAR OF 35-45 KT WILL KEEP THE RISK OF SEVERE STORMS ACROSS THE PANHANDLES YET AGAIN. THE TIME FRAME FOR STORMS TO DEVELOP WILL BE AROUND 4 PM WITH SEVERE POTENTIAL MAXIMIZING AFTER 6 PM. STORM WILL CONTINUE THROUGH MOST OF THE NIGHT BUT THE SEVERE RISK SHOULD SUBSIDE AFTER 3 AM. WEDNESDAY THROUGH THE WEEKEND...UPPER LEVEL RIDGING WILL RETURN TO THE PANHANDLES AND KEEP PRECIPITATION CHANCES LIMITED. THE RIDGE AXIS WILL MEANDER TO THE EAST AND BACK TO THE WEST WHICH WILL OPEN UP THE CHANCE FOR SOME PRECIP BUT HAVE KEPT THE FORECAST DRY GIVEN THE UNCERTAINTY ON THE AXIS PLACEMENT THIS FAR OUT. FIRE WEATHER... NEITHER ELEVATED NOR FIRE WEATHER CONDITIONS ARE EXPECTED FOR THE NEXT 7 DAYS GIVEN THE RECENT WETTING RAINS. && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 15/14
AREA FORECAST DISCUSSION
NWS AMARILLO TX
312 PM CDT MON JUN 17 2013 .DISCUSSION... TODAY AND TOMORROW REMAIN ACTIVE DAYS FOR THE TEXAS AND OKLAHOMA PANHANDLES. TEMPERATURES WERE SLOW TO COME UP THIS MORNING BUT HAVE BEGUN TO QUICKLY RISE ACROSS THE AREA. THERE WAS SOME CONCERN THAT THE SLOW HEATING WOULD DELAY INITIATION OF STORMS THIS AFTERNOON HOWEVER VISIBLE SATELLITE IMAGERY IS SHOWING A MILD CU FIELD DEVELOPING ACROSS THE EASTERN HALF OF THE PANHANDLES. ALSO CONVECTION OVER THE NEW MEXICO MOUNTAINS HAS INITIATED ONLY ABOUT A HOUR BEHIND WHAT WAS SHOWN IN THE 14Z RUC HRRR. AS SUCH THE PREVIOUS FORECAST SEVERE THREAT START TIME OF 6 PM REMAINS REALISTIC. WILL PAY CLOSE ATTENTION TO THE DEVELOPING CONVECTION ALONG THE RED RIVER AS IT COULD BACK BUILD ALONG A SOUTHWARD PROGRESSING COLD FRONT INTO COLLINGSWORTH COUNTY PRIOR TO 6 PM. THE SEVERE THREAT WILL LAST UNTIL 2-3AM TUESDAY WHEN STRONG CAPPING WILL SETUP HOWEVER...PRECIPITATION MAY LAST WELL PAST 3 AM. SPC MESO ANALYSIS HAS SHOWN A CONTINUAL DECREASING TREND OF CIN VALUES ACROSS THE WESTERN TEXAS AND OKLAHOMA PANHANDLES DURING THE SAME TIME SHOWING AN INCREASE OF SBCAPE VALUES. FORECAST SBCAPE VALUES OF 1500-2500 J/KG WITH DEEP LAYER SHEAR OF 35-40 KT CONTINUE SUPPORT LARGE HAIL AND DAMAGING WIND AS THE PRIMARY SEVERE HAZARDS. GIVEN SLOW STORM MOTIONS OF 15 TO 20 KTS...MOIST SOILS FROM PREVIOUS RAINS...AND PWAT VALUES NEAR AN INCH WILL KEEP LOCALIZED AND FLASH FLOODING AS A CONCERN WITH THESE STORMS. TOMORROW MODELS CONTINUE TO ADVERTISE REDEVELOPMENT OF STORMS ACROSS THE PANHANDLE. CAPE VALUES OF 1000-2000 J/KG AND DEEP SHEAR OF 35-45 KT WILL KEEP THE RISK OF SEVERE STORMS ACROSS THE PANHANDLES YET AGAIN. THE TIME FRAME FOR STORMS TO DEVELOP WILL BE AROUND 4 PM WITH SEVERE POTENTIAL MAXIMIZING AFTER 6 PM. STORM WILL CONTINUE THROUGH MOST OF THE NIGHT BUT THE SEVERE RISK SHOULD SUBSIDE AFTER 3 AM. WEDNESDAY THROUGH THE WEEKEND...UPPER LEVEL RIDGING WILL RETURN TO THE PANHANDLES AND KEEP PRECIPITATION CHANCES LIMITED. THE RIDGE AXIS WILL MEANDER TO THE EAST AND BACK TO THE WEST WHICH WILL OPEN UP THE CHANCE FOR SOME PRECIP BUT HAVE KEPT THE FORECAST DRY GIVEN THE UNCERTAINTY ON THE AXIS PLACEMENT THIS FAR OUT. && .FIRE WEATHER... NEITHER ELEVATED NOR FIRE WEATHER CONDITIONS ARE EXPECTED FOR THE NEXT 7 DAYS GIVEN THE RECENT WETTING RAINS. && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 15/14
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
106 PM CDT MON JUN 17 2013 .AVIATION... /18Z TAFS/ SEVERAL CHALLENGES ARE IN PLAY WITH THE 24 HOUR FORECAST AFTER OVERNIGHT MCS SWEPT THROUGH NORTH TEXAS THIS MORNING. A WEAK COLD FRONT IS EXPECTED TO MOVE ACROSS THE RED RIVER JUST BEFORE 00Z WITH SCATTERED STORMS DEVELOPING AHEAD OF THE FRONT. ANOTHER SHORTWAVE HELPS DEVELOP A POSSIBLE MCS OVER WEST-CENTRAL TX AND LOOKS TO ARRIVE FROM THE WEST LATE EVENING INTO THE PREDAWN HOURS TUESDAY. TIMING UNCERTAINTIES ABOUND WITH REGARD TO CONVECTIVE TRENDS AND THE MODELS CONTINUE TO STRUGGLE WITH OVER EVOLUTION. IN ADDITION...WIND SHIFTS AND SPEEDS ASSOCIATED WITH THE COLD FRONT AT DFW METRO AIRPORTS REMAINS PROBLEMATIC...AS DOES A BRIEF WINDOW FOR MVFR CIGS AROUND/AFTER ANY MCS. ISOLATED-SCATTERED STORMS SHOULD DEVELOP ALONG THE FRONT AND NORTH OF I-20...WEST TOWARD AN AREA OF HIGHER INSTABILITY NEAR A SURFACE LOW AROUND ABILENE. BEST CONSENSUS TIMING FROM THE MODELS FOR VCTS/CB IS BETWEEN 22Z-01Z AT METRO AIRPORTS FOR ACTIVITY NEAR THE COLD FRONT. THE OTHER WINDOW WILL BE BETWEEN 06Z-12Z FOR THE POTENTIAL MCS AT ALL AIRPORTS INCLUDING WACO. HAVE LEFT WACO OUT FOR ANY EARLY EVENING STORMS CONSIDERING THE WEAKER FORCING AND STRONGER SUBSIDENCE OVER CENTRAL TEXAS LATER THIS AFTERNOON. THERE WILL LIKELY BE SEVERAL ADJUSTMENTS TO TIMING AND THREATS THROUGH TONIGHT WHEN CONFIDENCE BECOMES HIGHER ON THE OVERALL EVOLUTION OF SHOWERS/STORMS. LIGHT SOUTH-SOUTHWEST FLOW WILL PREVAIL...THOUGH A SHIFT TO WEAK N/NE FLOW IS EXPECTED WITH THE COLD FRONT SINKING SOUTH ACROSS THE METRO AIRPORTS BY THIS EVENING. BEST WINDOW FOR MVFR CIGS WILL BE JUST BEFORE SUNRISE THROUGH MID MORNING TUESDAY. 05/ && .UPDATE... OUTFLOW BOUNDARY FROM COMPLEX OF STORMS THAT MOVED THROUGH THE AREA EARLIER THIS MORNING CONTINUES TO MOVE SOUTHEAST INTO PORTIONS OF CENTRAL AND SOUTHEAST TEXAS. SHOWERS AND THUNDERSTORMS ARE FORMING ALONG THE BOUNDARY BRINGING SOME RAIN TO OUR SOUTHEASTERN COUNTIES. DEPENDING ON WHERE THIS BOUNDARY STALLS...IT WILL LIKELY BE A FOCUS FOR POSSIBLE THUNDERSTORM DEVELOPMENT THIS AFTERNOON. IN ADDITION...THE FRONT WILL BE APPROACHING AND/OR CROSSING THE RED RIVER LATE THIS AFTERNOON...PROVIDING ANOTHER FOCUS FOR THUNDERSTORM DEVELOPMENT. AND FINALLY...SOME ATTENTION WILL ALSO BE GIVEN TO OUR WESTERN COUNTIES WHERE INSTABILITY AND HEATING WILL ALIGN FOR A THIRD POTENTIAL REGION OF THUNDERSTORM DEVELOPMENT. ANY STORMS THAT FORM THIS AFTERNOON WILL BE ISOLATED TO SCATTERED IN NATURE BUT A FEW STRONG TO MARGINALLY SEVERE STORMS WILL BE POSSIBLE. GUSTY WINDS AND HEAVY RAINFALL WILL BE THE MAIN THREATS BUT SOME SMALL HAIL IS ALSO POSSIBLE. FOR THE AFTERNOON HOURS...UPDATED THE FORECAST TO CARRY 30 POPS ACROSS THE REGION WITH 40 POPS NEAR THE RED RIVER. FOR THIS EVENING AND OVERNIGHT...SOME OF THE SHORT-TERM HI-RES MODELS CONTINUE TO INDICATE A COMPLEX OF STORMS DEVELOPING IN WEST TEXAS AND POSSIBLY REACHING PORTIONS OF NORTH TEXAS OVERNIGHT OR TUESDAY MORNING. WILL MAINTAIN HIGHEST POPS OVERNIGHT OVER THE WESTERN COUNTIES BUT CHANGES MAY BE NEEDED WITH THE AFTERNOON FORECAST PACKAGE. 82/JLD && .PREV DISCUSSION... /ISSUED 353 AM CDT MON JUN 17 2013/ A LARGE MCS WILL CONTINUE MOVING SOUTHEAST TOWARD NORTH TEXAS EARLY THIS MORNING AND SHOULD REACH THE NORTHWEST ZONES SHORTLY BEFORE 6 AM AS PER THE HRRR AND 4KM WRF SOLUTIONS AS WELL AS LINEAR EXTRAPOLATION. THE COMPLEX SHOULD WEAKEN AS IT MOVES FARTHER AWAY FROM ITS UPPER SUPPORT AND ALSO ONCE A 30 KNOT LOW LEVEL JET DECREASES LATER THIS MORNING. THIS SOLUTION IS ALSO SUPPORTED BY THE HRRR AND 4KM WRF. WE STILL EXPECT EXTENSIVE CLOUD COVER AND SCATTERED TO NUMEROUS STORMS...THROUGH THE MORNING WITH THE EXPECTED TIME OF ARRIVAL OF STORMS AT THE METROPLEX BETWEEN 13 AND 15Z. SOME IMPRESSIVE WIND GUSTS BETWEEN 50 AND 55 KNOTS ARE OCCURRING WITH THE COMPLEX. IT IS VERY POSSIBLE THAT SOME SIMILAR WIND GUSTS COULD OCCUR ACROSS THE NORTHWEST CWA BY 6 AM. EXPECT STORMS TO BECOME LESS ORGANIZED BY MIDDAY AND AFFECT MAINLY THE EAST/NORTHEAST ZONES. MODELS ARE CONSISTENT ON DEVELOPING MORE STORMS ACROSS WEST TEXAS ALONG A FAST MOVING SHORT WAVE AND COLD FRONT LATE THIS AFTERNOON. AM A BIT CONCERNED THAT EXTENSIVE OVERNIGHT/MORNING CONVECTION MAY HINDER STORM DEVELOPMENT THIS AFTERNOON. HOWEVER...THE ATMOSPHERE MAY HAVE JUST ENOUGH TIME TO RECOVER BEFORE SURFACE HEATING IS LOST. STORMS SHOULD ORGANIZE ALONG THE COLD FRONT AND MOVE SOUTHEAST INTO NORTH TEXAS TONIGHT/TUESDAY MORNING. AGAIN...WILL KEEP THE HIGHEST POPS ACROSS THE NORTHERN ZONES. THE COLD FRONT IS PROGGED TO STALL ACROSS THE NORTHERN HALF OF THE REGION TUESDAY NIGHT AND LIFT NORTH OF THE RED RIVER BY WEDNESDAY EVENING. AFTER WEDNESDAY...UPPER LEVEL HIGH PRESSURE WILL BUILD FROM TEXAS...NORTHWARD THROUGH THE CENTRAL PLAINS. THIS PATTERN WILL RESULT IN HOT TEMPERATURES AND LITTLE RAIN CHANCES WEDNESDAY NIGHT THROUGH EARLY NEXT WEEK. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK MAINLY IN THE LOWER AND MIDDLE 90S...EXPERT FOR SOME UPPER 90S IN THE WEST. OVERNIGHT LOWS WILL BE IN THE 70S THROUGH EARLY NEXT WEEK. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 89 77 92 75 95 / 30 30 30 20 20 WACO, TX 91 75 93 74 94 / 30 40 20 20 10 PARIS, TX 87 73 87 72 88 / 40 30 40 40 40 DENTON, TX 88 75 92 73 94 / 40 30 40 30 20 MCKINNEY, TX 88 73 90 73 92 / 40 30 40 30 20 DALLAS, TX 90 77 92 76 93 / 30 30 30 20 20 TERRELL, TX 88 75 91 73 92 / 60 30 30 20 20 CORSICANA, TX 91 74 91 74 92 / 60 40 20 20 10 TEMPLE, TX 95 72 92 73 92 / 30 40 20 10 10 MINERAL WELLS, TX 90 72 92 71 95 / 30 40 30 20 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/82
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1110 AM CDT MON JUN 17 2013 .UPDATE... OUTFLOW BOUNDARY FROM COMPLEX OF STORMS THAT MOVED THROUGH THE AREA EARLIER THIS MORNING CONTINUES TO MOVE SOUTHEAST INTO PORTIONS OF CENTRAL AND SOUTHEAST TEXAS. SHOWERS AND THUNDERSTORMS ARE FORMING ALONG THE BOUNDARY BRINGING SOME RAIN TO OUR SOUTHEASTERN COUNTIES. DEPENDING ON WHERE THIS BOUNDARY STALLS...IT WILL LIKELY BE A FOCUS FOR POSSIBLE THUNDERSTORM DEVELOPMENT THIS AFTERNOON. IN ADDITION...THE FRONT WILL BE APPROACHING AND/OR CROSSING THE RED RIVER LATE THIS AFTERNOON...PROVIDING ANOTHER FOCUS FOR THUNDERSTORM DEVELOPMENT. AND FINALLY...SOME ATTENTION WILL ALSO BE GIVEN TO OUR WESTERN COUNTIES WHERE INSTABILITY AND HEATING WILL ALIGN FOR A THIRD POTENTIAL REGION OF THUNDERSTORM DEVELOPMENT. ANY STORMS THAT FORM THIS AFTERNOON WILL BE ISOLATED TO SCATTERED IN NATURE BUT A FEW STRONG TO MARGINALLY SEVERE STORMS WILL BE POSSIBLE. GUSTY WINDS AND HEAVY RAINFALL WILL BE THE MAIN THREATS BUT SOME SMALL HAIL IS ALSO POSSIBLE. FOR THE AFTERNOON HOURS...UPDATED THE FORECAST TO CARRY 30 POPS ACROSS THE REGION WITH 40 POPS NEAR THE RED RIVER. FOR THIS EVENING AND OVERNIGHT...SOME OF THE SHORT-TERM HI-RES MODELS CONTINUE TO INDICATE A COMPLEX OF STORMS DEVELOPING IN WEST TEXAS AND POSSIBLY REACHING PORTIONS OF NORTH TEXAS OVERNIGHT OR TUESDAY MORNING. WILL MAINTAIN HIGHEST POPS OVERNIGHT OVER THE WESTERN COUNTIES BUT CHANGES MAY BE NEEDED WITH THE AFTERNOON FORECAST PACKAGE. 82/JLD && .PREV UPDATE... .UPDATE... A COMPLEX OF THUNDERSTORMS CONTINUES TO WEAKEN AS IT PROGRESSES THROUGH ROUGHLY THE EASTERN HALF OF THE CWA. GUSTY WINDS TO 30-40 MPH MAY STILL OCCUR ALONG THE LEADING EDGE BUT OTHERWISE BRIEF HEAVY RAINFALL AND LIGHTNING STRIKES WILL BE THE MAIN THREATS. HAVE UPDATED THE FORECAST TO REFLECT THE LATEST RADAR...TEMP...SKY TRENDS FOR THE NEXT FEW HOURS. ALSO DECREASED AFTERNOON TEMPERATURES A FEW DEGREES FOR NOW AND WILL LOOK AT TEMPS AGAIN THROUGH THE MORNING HOURS. WE ARE STILL WORKING TO EVALUATE PRECIPITATION CHANCES AND TRENDS FOR THE REMAINDER OF THE DAY AND TONIGHT. THERE IS ALREADY DISCREPANCIES AMONG THE MODELS ON PRECIP EVOLUTION LATER TODAY AND NOW THE COMPLEX OF THUNDERSTORMS THIS MORNING WILL LIKELY ALSO EFFECT TRENDS. WILL LIKELY BE ISSUING ANOTHER UPDATE BY MIDDAY AFTER TAKING A CLOSER LOOK AND EVALUATING THE 12Z/LATEST MODEL DATA. 82/JLD && .PREV DISCUSSION... /ISSUED 353 AM CDT MON JUN 17 2013/ A LARGE MCS WILL CONTINUE MOVING SOUTHEAST TOWARD NORTH TEXAS EARLY THIS MORNING AND SHOULD REACH THE NORTHWEST ZONES SHORTLY BEFORE 6 AM AS PER THE HRRR AND 4KM WRF SOLUTIONS AS WELL AS LINEAR EXTRAPOLATION. THE COMPLEX SHOULD WEAKEN AS IT MOVES FARTHER AWAY FROM ITS UPPER SUPPORT AND ALSO ONCE A 30 KNOT LOW LEVEL JET DECREASES LATER THIS MORNING. THIS SOLUTION IS ALSO SUPPORTED BY THE HRRR AND 4KM WRF. WE STILL EXPECT EXTENSIVE CLOUD COVER AND SCATTERED TO NUMEROUS STORMS...THROUGH THE MORNING WITH THE EXPECTED TIME OF ARRIVAL OF STORMS AT THE METROPLEX BETWEEN 13 AND 15Z. SOME IMPRESSIVE WIND GUSTS BETWEEN 50 AND 55 KNOTS ARE OCCURRING WITH THE COMPLEX. IT IS VERY POSSIBLE THAT SOME SIMILAR WIND GUSTS COULD OCCUR ACROSS THE NORTHWEST CWA BY 6 AM. EXPECT STORMS TO BECOME LESS ORGANIZED BY MIDDAY AND AFFECT MAINLY THE EAST/NORTHEAST ZONES. MODELS ARE CONSISTENT ON DEVELOPING MORE STORMS ACROSS WEST TEXAS ALONG A FAST MOVING SHORT WAVE AND COLD FRONT LATE THIS AFTERNOON. AM A BIT CONCERNED THAT EXTENSIVE OVERNIGHT/MORNING CONVECTION MAY HINDER STORM DEVELOPMENT THIS AFTERNOON. HOWEVER...THE ATMOSPHERE MAY HAVE JUST ENOUGH TIME TO RECOVER BEFORE SURFACE HEATING IS LOST. STORMS SHOULD ORGANIZE ALONG THE COLD FRONT AND MOVE SOUTHEAST INTO NORTH TEXAS TONIGHT/TUESDAY MORNING. AGAIN...WILL KEEP THE HIGHEST POPS ACROSS THE NORTHERN ZONES. THE COLD FRONT IS PROGGED TO STALL ACROSS THE NORTHERN HALF OF THE REGION TUESDAY NIGHT AND LIFT NORTH OF THE RED RIVER BY WEDNESDAY EVENING. AFTER WEDNESDAY...UPPER LEVEL HIGH PRESSURE WILL BUILD FROM TEXAS...NORTHWARD THROUGH THE CENTRAL PLAINS. THIS PATTERN WILL RESULT IN HOT TEMPERATURES AND LITTLE RAIN CHANCES WEDNESDAY NIGHT THROUGH EARLY NEXT WEEK. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK MAINLY IN THE LOWER AND MIDDLE 90S...EXPERT FOR SOME UPPER 90S IN THE WEST. OVERNIGHT LOWS WILL BE IN THE 70S THROUGH EARLY NEXT WEEK. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 89 77 92 75 95 / 30 30 30 20 20 WACO, TX 91 75 93 74 94 / 30 40 20 20 10 PARIS, TX 87 73 87 72 88 / 40 30 40 40 40 DENTON, TX 88 75 92 73 94 / 40 30 40 30 20 MCKINNEY, TX 88 73 90 73 92 / 40 30 40 30 20 DALLAS, TX 90 77 92 76 93 / 30 30 30 20 20 TERRELL, TX 88 75 91 73 92 / 60 30 30 20 20 CORSICANA, TX 91 74 91 74 92 / 60 40 20 20 10 TEMPLE, TX 95 72 92 73 92 / 30 40 20 10 10 MINERAL WELLS, TX 90 72 92 71 95 / 30 40 30 20 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/82
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
930 AM CDT MON JUN 17 2013 .UPDATE... A COMPLEX OF THUNDERSTORMS CONTINUES TO WEAKEN AS IT PROGRESSES THROUGH ROUGHLY THE EASTERN HALF OF THE CWA. GUSTY WINDS TO 30-40 MPH MAY STILL OCCUR ALONG THE LEADING EDGE BUT OTHERWISE BRIEF HEAVY RAINFALL AND LIGHTNING STRIKES WILL BE THE MAIN THREATS. HAVE UPDATED THE FORECAST TO REFLECT THE LATEST RADAR...TEMP...SKY TRENDS FOR THE NEXT FEW HOURS. ALSO DECREASED AFTERNOON TEMPERATURES A FEW DEGREES FOR NOW AND WILL LOOK AT TEMPS AGAIN THROUGH THE MORNING HOURS. WE ARE STILL WORKING TO EVALUATE PRECIPITATION CHANCES AND TRENDS FOR THE REMAINDER OF THE DAY AND TONIGHT. THERE IS ALREADY DISCREPANCIES AMONG THE MODELS ON PRECIP EVOLUTION LATER TODAY AND NOW THE COMPLEX OF THUNDERSTORMS THIS MORNING WILL LIKELY ALSO EFFECT TRENDS. WILL LIKELY BE ISSUING ANOTHER UPDATE BY MIDDAY AFTER TAKING A CLOSER LOOK AND EVALUATING THE 12Z/LATEST MODEL DATA. 82/JLD && .PREV DISCUSSION... /ISSUED 353 AM CDT MON JUN 17 2013/ A LARGE MCS WILL CONTINUE MOVING SOUTHEAST TOWARD NORTH TEXAS EARLY THIS MORNING AND SHOULD REACH THE NORTHWEST ZONES SHORTLY BEFORE 6 AM AS PER THE HRRR AND 4KM WRF SOLUTIONS AS WELL AS LINEAR EXTRAPOLATION. THE COMPLEX SHOULD WEAKEN AS IT MOVES FARTHER AWAY FROM ITS UPPER SUPPORT AND ALSO ONCE A 30 KNOT LOW LEVEL JET DECREASES LATER THIS MORNING. THIS SOLUTION IS ALSO SUPPORTED BY THE HRRR AND 4KM WRF. WE STILL EXPECT EXTENSIVE CLOUD COVER AND SCATTERED TO NUMEROUS STORMS...THROUGH THE MORNING WITH THE EXPECTED TIME OF ARRIVAL OF STORMS AT THE METROPLEX BETWEEN 13 AND 15Z. SOME IMPRESSIVE WIND GUSTS BETWEEN 50 AND 55 KNOTS ARE OCCURRING WITH THE COMPLEX. IT IS VERY POSSIBLE THAT SOME SIMILAR WIND GUSTS COULD OCCUR ACROSS THE NORTHWEST CWA BY 6 AM. EXPECT STORMS TO BECOME LESS ORGANIZED BY MIDDAY AND AFFECT MAINLY THE EAST/NORTHEAST ZONES. MODELS ARE CONSISTENT ON DEVELOPING MORE STORMS ACROSS WEST TEXAS ALONG A FAST MOVING SHORT WAVE AND COLD FRONT LATE THIS AFTERNOON. AM A BIT CONCERNED THAT EXTENSIVE OVERNIGHT/MORNING CONVECTION MAY HINDER STORM DEVELOPMENT THIS AFTERNOON. HOWEVER...THE ATMOSPHERE MAY HAVE JUST ENOUGH TIME TO RECOVER BEFORE SURFACE HEATING IS LOST. STORMS SHOULD ORGANIZE ALONG THE COLD FRONT AND MOVE SOUTHEAST INTO NORTH TEXAS TONIGHT/TUESDAY MORNING. AGAIN...WILL KEEP THE HIGHEST POPS ACROSS THE NORTHERN ZONES. THE COLD FRONT IS PROGGED TO STALL ACROSS THE NORTHERN HALF OF THE REGION TUESDAY NIGHT AND LIFT NORTH OF THE RED RIVER BY WEDNESDAY EVENING. AFTER WEDNESDAY...UPPER LEVEL HIGH PRESSURE WILL BUILD FROM TEXAS...NORTHWARD THROUGH THE CENTRAL PLAINS. THIS PATTERN WILL RESULT IN HOT TEMPERATURES AND LITTLE RAIN CHANCES WEDNESDAY NIGHT THROUGH EARLY NEXT WEEK. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK MAINLY IN THE LOWER AND MIDDLE 90S...EXPERT FOR SOME UPPER 90S IN THE WEST. OVERNIGHT LOWS WILL BE IN THE 70S THROUGH EARLY NEXT WEEK. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 77 92 75 95 / 100 30 30 20 20 WACO, TX 91 75 93 74 94 / 40 20 20 20 10 PARIS, TX 89 73 87 72 88 / 100 30 40 40 40 DENTON, TX 91 75 92 73 94 / 100 30 40 30 20 MCKINNEY, TX 90 73 90 73 92 / 100 30 40 30 20 DALLAS, TX 92 77 92 76 93 / 100 30 30 20 20 TERRELL, TX 91 75 91 73 92 / 100 20 30 20 20 CORSICANA, TX 91 74 91 74 92 / 100 20 20 20 10 TEMPLE, TX 91 72 92 73 92 / 20 20 20 10 10 MINERAL WELLS, TX 92 72 92 71 95 / 30 30 30 20 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/82
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
353 AM CDT MON JUN 17 2013 .DISCUSSION... A LARGE MCS WILL CONTINUE MOVING SOUTHEAST TOWARD NORTH TEXAS EARLY THIS MORNING AND SHOULD REACH THE NORTHWEST ZONES SHORTLY BEFORE 6 AM AS PER THE HRRR AND 4KM WRF SOLUTIONS AS WELL AS LINEAR EXTRAPOLATION. THE COMPLEX SHOULD WEAKEN AS IT MOVES FARTHER AWAY FROM ITS UPPER SUPPORT AND ALSO ONCE A 30 KNOT LOW LEVEL JET DECREASES LATER THIS MORNING. THIS SOLUTION IS ALSO SUPPORTED BY THE HRRR AND 4KM WRF. WE STILL EXPECT EXTENSIVE CLOUD COVER AND SCATTERED TO NUMEROUS STORMS...THROUGH THE MORNING WITH THE EXPECTED TIME OF ARRIVAL OF STORMS AT THE METROPLEX BETWEEN 13 AND 15Z. SOME IMPRESSIVE WIND GUSTS BETWEEN 50 AND 55 KNOTS ARE OCCURRING WITH THE COMPLEX. IT IS VERY POSSIBLE THAT SOME SIMILAR WIND GUSTS COULD OCCUR ACROSS THE NORTHWEST CWA BY 6 AM. EXPECT STORMS TO BECOME LESS ORGANIZED BY MIDDAY AND AFFECT MAINLY THE EAST/NORTHEAST ZONES. MODELS ARE CONSISTENT ON DEVELOPING MORE STORMS ACROSS WEST TEXAS ALONG A FAST MOVING SHORT WAVE AND COLD FRONT LATE THIS AFTERNOON. AM A BIT CONCERNED THAT EXTENSIVE OVERNIGHT/MORNING CONVECTION MAY HINDER STORM DEVELOPMENT THIS AFTERNOON. HOWEVER...THE ATMOSPHERE MAY HAVE JUST ENOUGH TIME TO RECOVER BEFORE SURFACE HEATING IS LOST. STORMS SHOULD ORGANIZE ALONG THE COLD FRONT AND MOVE SOUTHEAST INTO NORTH TEXAS TONIGHT/TUESDAY MORNING. AGAIN...WILL KEEP THE HIGHEST POPS ACROSS THE NORTHERN ZONES. THE COLD FRONT IS PROGGED TO STALL ACROSS THE NORTHERN HALF OF THE REGION TUESDAY NIGHT AND LIFT NORTH OF THE RED RIVER BY WEDNESDAY EVENING. AFTER WEDNESDAY...UPPER LEVEL HIGH PRESSURE WILL BUILD FROM TEXAS...NORTHWARD THROUGH THE CENTRAL PLAINS. THIS PATTERN WILL RESULT IN HOT TEMPERATURES AND LITTLE RAIN CHANCES WEDNESDAY NIGHT THROUGH EARLY NEXT WEEK. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK MAINLY IN THE LOWER AND MIDDLE 90S...EXPERT FOR SOME UPPER 90S IN THE WEST. OVERNIGHT LOWS WILL BE IN THE 70S THROUGH EARLY NEXT WEEK. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 97 77 92 75 95 / 20 30 30 20 20 WACO, TX 95 75 93 74 94 / 10 20 20 20 10 PARIS, TX 93 73 87 72 88 / 50 30 40 40 40 DENTON, TX 98 75 92 73 94 / 40 30 40 30 20 MCKINNEY, TX 94 73 90 73 92 / 30 30 40 30 20 DALLAS, TX 96 77 92 76 93 / 20 30 30 20 20 TERRELL, TX 95 75 91 73 92 / 20 20 30 20 20 CORSICANA, TX 95 74 91 74 92 / 10 20 20 20 10 TEMPLE, TX 95 72 92 73 92 / 5 20 20 10 10 MINERAL WELLS, TX 96 72 92 71 95 / 30 30 30 20 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 91/79
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1022 PM EDT TUE JUN 18 2013 .SYNOPSIS... A COLD FRONT EXTENDED FROM SOUTHEAST VIRGINIA INTO THE LOWER MISSISSIPPI VALLEY AND A SECOND FRONT STRETCHED FROM NEW JERSEY INTO THE MID MISSISSIPPI VALLEY. THIS SECOND FRONT WILL DROP SOUTH THROUGH THE MID ATLANTIC REGION ON WEDNESDAY. WEAK HIGH PRESSURE WILL BUILD INTO THE AREA WEDNESDAY NIGHT AND THURSDAY...RESULTING IN SOMEWHAT DRIER WEATHER INTO THE END OF THE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1015 PM EDT TUESDAY... THE COLD FRONT WAS WELL SOUTH OF THE FORECAST AREA AT 02Z/10PM. SATELLITE PICTURES SHOWED SCATTERED CLOUDS OVER THE FORECAST AREA. ENOUGH CLEARING AND HIGH ENOUGH DEW POINTS TO ADD MORE FOG TO THE FORECAST FOR TONIGHT. LATEST WRF AND RAP GUIDANCE SUGGESTED LOW LEVEL MOISTURE AND A CHANCE OF SHOWERS OVER SOUTHEAST WEST VIRGINIA OVERNIGHT AND IN THE VIRGINIA PIEDMONT EARLY WEDNESDAY MORNING. THE NEXT COLD FRONT OVER THE OHIO VALLEY WILL APPROACH THE FORECAST AREA AFTER MIDNIGHT. MODELS HAVE ONLY A LOW CHANCE OF PRECIPITATION WITH THIS FRONT. HAVE ALIGNED THE HIGHER PROBABILITY OF PRECIPITATION AHEAD OF THIS FRONT AND KEPT A LOW CHANCE IN THE PIEDMONT LATE TONIGHT. THE BROAD TROUGH ACROSS EAST COAST WILL SHIFT SLIGHTLY EASTWARD AS THE UPPER RIDGING BUILDS. IT WILL REMAIN WARM AND HUMID OVERNIGHT WITH LOW TEMPERATURES FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S IN THE SOUTHEAST. KEPT THE LIGHT POPS IN FOR WEDNESDAY WITH BEST CHANCES ACROSS THE SOUTH. PLAYED HIGHS WEDNESDAY CLOSER TO COOLER MOS VALUES FROM THE UPPER 60S IN THE WESTERN MOUNTAINS TO THE LOWER 80S IN THE PIEDMONT. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... AS OF 345 PM EDT TUESDAY... SUBSIDENCE AND DRYING ALOFT INCREASES FOR THE LATER HALF OF THE WEEK AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE NORTH WEDNESDAY NIGHT AND THURSDAY...WITH A BROAD EASTERLY COMPONENT TO THE WIND AS THE HIGH DRIFTS TO ALONG THE COAST LATE THURSDAY INTO FRIDAY. WITH HEIGHTS BUILDING ALOFT...AND A DRY MID LEVEL EASTERLY WIND...LOOKING AT MAINLY TRANQUIL WEATHER WITH LITTLE OR NO PRECIP THREAT. TEMPERATURES WILL BE NEAR SEASONAL...NOT TOO HOT...NOT TOO COOL. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 345 PM EDT TUESDAY... MODERATING TEMPERATURES EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK AS THE UPPER LEVEL RIDGE CONTINUES TO BUILD...850 TEMPS CREEPING TOWARD +2OC FOR MONDAY AND TUESDAY. THIS SUGGESTS SURFACE TEMPS WILL TOP OUT MAINLY IN THE 80SF...TESTING 90F DEGREES FOR THE URBAN AREAS. NO REAL FOCUS FOR DEEP CONVECTION DURING THE PERIOD EXCEPT FOR CONVERGENCE OVER THE MTNS...SO KEPT ANY PRECIP THREAT MAINLY DIURNAL AND PRIMARILY TARGETED TO THE MTNS. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... AS OF 745 PM EDT TUESDAY... POOR AVIATION CONDITIONS EXPECTED THROUGH WEDNESDAY MORNING. THE CURRENT SYSTEM WILL CONTINUE TO EXIT THE REGION FROM THE WEST...BUT EXPECT LOW-LEVEL AIR MASS WILL REMAIN VERY MOIST AND AREAS OF MVFR-IFR CIGS/VSBYS IN BR/FZ LIKELY PERSIST THROUGHOUT THE NIGHT. EXTENDED AVIATION CONDITIONS...FOR THURSDAY INTO THE WEEKEND...INCREASED DIURNAL CONVECTION...ESPECIALLY ALONG THE APPALACHIANS...WITH LOCALLY BRIEF MVFR-IFR CIGS/VSBYS IN TSRA. AREAS OF MVFR-IFR VSBYS BR...LOCALLY IFR FG...ALSO POSSIBLE DURING THE MORNING HOURS. MEDIUM CONFIDENCE IN CIGS THROUGH TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH TAF VALID PERIOD. MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID PERIOD. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/KK NEAR TERM...AMS/KK SHORT TERM...PM LONG TERM...PM AVIATION...JC/KK/RAB
AREA FORECAST DISCUSSION
NWS SPOKANE WA
440 PM PDT Tue Jun 18 2013 .SYNOPSIS... Scattered showers and a few thunderstorms will continue Tuesday night. By Wednesday a wet and cool weather pattern will take hold of the region. Showery and cool conditions will continue through the week, with a drying and warming trend expected this weekend. Wetter and cooler weather will return early next week. && .DISCUSSION... Tonight and Tomorrow...Offshore low pressure pushing up against higher pressure inland has a moist and unstable flow in between. This is being utilized by smaller mesoscale disturbances and other triggers to generate both surface and forced elevated showers and thunderstorms through this interval. HRRR model runs have been utilized for the short term hours of tonight to time the breaks in precipitation and allow for the weakening but not really dissipating north to south oriented band of showers affecting locations in the lowlands from near Moses Lake and up north to Republic. Tonight a disturbances rotating around the periphery of the incoming large scale low will fire off more showers and thunderstorms and take them in a south to north trajectory with storm motion near 30 mph or so through Eastern Washington and North Idaho overnight and into Tomorrow. Number of GFS runs hint at some of the later convection being highly organized and thus of longer duration late tonight and into tomorrow which means there should be a significant amount of rainfall. Thus the forecast hints at some locations in the North Idaho Panhandle receiving up to one and one half inches of rainfall in 24 hours...which should increase flow in area rivers and streams. In addition to the significant rainfall and as is usually the case gusty wind and small hail is possible near any of these thunderstorms. /Pelatti ...PERSISTENT BAND OF MODERATE RAIN WEDNESDAY INTO THURSDAY FOR THE IDAHO PANHANDLE MAY CAUSE LOCALIZED FLOODING... Wednesday through Friday: The biggest concern for the Wednesday through Thursday time frame will be the amount of rain that will fall over the Inland Northwest. A slow moving upper level low will pivot through northeast Oregon into the Idaho Panhandle and stall on Thursday into Friday. Deformation band precip (rain wrapping around the low) should bring a prolonged period of moderate rain to the Idaho Panhandle, western Montana and southern British Columbia. We preferred the 00z/12z ECMWF blended the 15z SREF to build our multi-day precipitation totals. The operational runs of the NAM and GFS aren`t terribly different with their placement of the upper low and other mass fields, but these operational models do become noisy from time to time with convective feedback. The ensemble SREF and coarser EC suffer from less feedback which will hopefully lead to a better basin average precipitation forecast. The highest precipitation totals from early Wednesday morning through Friday will likely occur over the Idaho Panhandle, namely Bonner, Boundary and Shoshone counties where as much as 2 to 2.5 inches of rain will be possible through Friday. Areas in far northeast Washington around Metaline Falls, Newport, and Northport could get up to 2 inches as well. Rainfall rates don`t appear to be particularly heavy, but the ECMWF and SREF (which will be conservative) suggest the heaviest rates will occur Wednesday morning with as much as a half to three quarters of an inch in 6 hours within a localized band. Most areas should be able to handle these precipitation rates. The 12z-18z NAM has almost double these rain rates (up to 1.25 inches per 6 hours) which could cause some problems on creeks and small streams. Concern Area #1: The Idaho Panhandle and southeast British Columbia. A Flood Watch may be necessary for Wednesday for portions of the Idaho Panhandle for creeks and small streams. Another concern will be the large amount of precipitation from Wednesday through Friday over the Kootenai Basin in southeast BC, NW Montana and far north Idaho. Rises are forecast on the Kootenai at Bonners Ferry. The potential for more rain next week is not particularly good news, but it is early to say whether rains next week will be significant enough to generate run-off. Concern Area #2: The burn scars in central Washington around Wenatchee, Chelan and Entiat. Fortunately, the deformation band with the upper low will be well east of the burn scar area on Wednesday. There is a small chance on Thursday, that this band will pivot into central Washington, but it will not likely maintain precipitation intensity into Thursday. There will also be a small chance of thunderstorms on Wednesday. The atmosphere does not appear to be particularly unstable with a 500mb temp of only -18C to -19C. There should also be a good deal of low cloudiness Wednesday which should inhibit surface heating throughout the day. All-in-all, the threat of flash flood appears to be low over the burn scars through Friday. /GKoch Friday Night thru Sunday Night... Lingering showers and cool temperatures will continue over eastern sections of the CWA Friday night as the persistent upper low slowly moves east from the southern part of the Idaho Panhandle. Differences in timing between the EC and GFS cast doubt on how fast the system will move east on Saturday and while the Cascades and Basin will have mostly clear skies and warming temperatures, showers may linger over the Idaho Panhandle. By Saturday night and early Sunday all models agree that the CWA will be in between systems and under a weak short wave ridge. The EC then brings in the next system off the Pacific by Sunday afternoon with an increasing threat for showers over the Cascades. Precip is on the increase Sunday night as the ridge moves quickly east and the flows becomes westerly. JL Monday and Tuesday...It looks like another moist storm system will be affecting the Inland Northwest next week, bringing increased rain chances to many areas. There is decent model agreement regarding this system, with only some slight timing differences. We went ahead and bumped up precipitation chances, especially along the Cascade crest. With what is going to fall over the next couple of days, anything of significance rainfall wise may cause some hydrology issues. This is definitely something to watch out for. ty && .AVIATION... 00Z TAFS: Another round of showers and thunderstorms will affect all of the TAF sites this evening with moderate rain and some MVFR cigs. A band of moderate to heavy rain will develop late tonight along the WA/ID border, and persist through much of Wednesday. This will bring IFR conditions to most of the eastern TAF sites all day. KGEG will be on the western edge of this band and conditions may improve a bit in the late afternoon. KSFF and certainly KCOE will feel the brunt of this event. To the south, KPUW and LWS may see some improvement in the afternoon but I didn`t have enough confidence in this. KMWH and KEAT should remain out of the action for the most part and will actually have better conditions tomorrow than today. RJ && .PRELIMINARY POINT TEMPS/POPS... Spokane 52 54 45 55 44 61 / 80 100 80 80 50 60 Coeur d`Alene 52 54 46 54 42 60 / 90 100 100 90 50 60 Pullman 49 53 44 56 42 60 / 80 100 70 60 30 60 Lewiston 54 58 49 64 44 67 / 70 100 70 60 20 50 Colville 51 63 50 57 48 67 / 90 100 100 100 60 50 Sandpoint 50 56 46 53 45 60 / 100 100 100 100 60 60 Kellogg 50 51 44 51 39 57 / 100 100 100 100 50 60 Moses Lake 55 66 51 65 49 69 / 70 50 50 60 30 30 Wenatchee 56 66 52 64 51 68 / 40 40 50 60 40 30 Omak 53 66 51 64 50 69 / 60 80 70 80 60 50 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1056 AM PDT Mon Jun 17 2013 .SYNOPSIS... An increasing chance of showers and thunderstorms comes to the Inland Northwest today through Tuesday. By Wednesday downright wet and cool weather envelopes the region. Expect a gradual cool down starting today, with afternoon temperatures bottoming out well below normal by Wednesday. Showery, cool conditions will continue through the week, with a drying and warming trend by the weekend. && .DISCUSSION... Updates may occur before the 3 PM afternoon zone issuance as a number of recent HRRR runs have a persistent trend in forming very fast moving elevated convection across the far western part of the forecast area starting near 4 pm and on through the evening. Otherwise to complicated the matter elevated convective showers from last night along with new surface based convection should continue to clutter primarily the northern third of the forecast area. Best way to convey this situation is probably with the description above rather than point probabilities and forecast zone wording. 12Z KOTX sounding shows storm motion to the northeast at 15 mph or so for surface based convection but the elevated type near the west side of the forecast area should move faster to the northeast at near 35 mph or so (per quick view of GFS 1-6KM AGL mean wind-speed for 00Z Tuesday). Any thunderstorms that form should be of the weak pulse variety. /Pelatti && .AVIATION... 18z TAFS: Low pressure off the coast next to inland ridge of high pressure will allow a somewhat warm and unstable flow from the south to allow for the possibility of convective showers and thunderstorms for TAF sites. Surface based showers and thunderstorms should occur primarily over the Mountains to the north of Northeast Washington and North Idaho while elevated showers and thunderstorms should occur after 00Z Tuesday and on through the evening and overnight, possibly lingering on as various disturbances move up from the south and on into 18Z Tuesday. /Pelatti && .PRELIMINARY POINT TEMPS/POPS... Spokane 82 56 75 50 58 46 / 20 50 50 80 100 70 Coeur d`Alene 81 55 75 51 55 46 / 20 50 50 80 100 80 Pullman 81 50 72 47 59 43 / 10 20 50 70 90 70 Lewiston 88 57 82 54 66 49 / 10 20 40 70 70 70 Colville 83 53 79 50 60 47 / 30 50 60 80 100 80 Sandpoint 82 52 81 49 56 44 / 30 50 50 90 100 80 Kellogg 79 55 80 50 54 44 / 20 20 40 90 100 80 Moses Lake 86 57 75 54 66 50 / 10 50 50 50 60 40 Wenatchee 83 60 74 56 64 52 / 20 40 60 40 60 40 Omak 83 54 77 52 65 49 / 20 40 70 60 100 60 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1255 PM CDT MON JUN 17 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 307 AM CDT MON JUN 17 2013 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...RIDGING BUILDING FROM NEW MEXICO INTO BRITISH COLUMBIA...AND TROUGHING OVER SOUTHEAST CANADA INTO THE EASTERN GREAT LAKES. WITHIN THE WEST-NORTHWEST FLOW...TWO SHORTWAVES OF NOTE WERE NEAR FARGO NORTH DAKOTA AND IN FAR SOUTHWEST SASKATCHEWAN. 700-850MB MOISTURE TRANSPORT AHEAD OF THE FARGO SHORTWAVE HELPING TO SUPPORT SOME HIGH BASED SHOWERS ALONG/NORTHEAST OF I-94. TALKING ABOUT HIGH BASED... 00Z MPX AND GRB SOUNDINGS BOTH DEPICTED MIXING UP TO 750MB...WITH DEEP INVERTED-V APPEARANCE BELOW. THIS DEEP MIXING ALLOWED FOR SHOWERS THAT MOVED THROUGH MPX AROUND RAOB RELEASE TIME TO PRODUCE WIND GUSTS OF 30-50KT. THESE SHOWERS WERE MORE VIGOROUS THEN THOSE OCCURRING NOW...PLUS THEY OCCURRED RIGHT AFTER PEAK HEATING WHEN MIXING WAS AT ITS MAXIMUM...ALLOWING FOR THE STRONG GUST POTENTIAL. OTHERWISE...SKIES ARE MOSTLY CLEAR OVER THE FORECAST AREA SOUTH OF A COLD FRONT EXTENDING FROM NORTHERN MN INTO NORTHERN LOWER MI. 850MB TEMPS AT 00Z AHEAD OF THE FRONT WERE 14-16C AT MPX...GRB AND DVN...COMPARED TO 4C BEHIND THE FRONT UP AT PICKLE LAKE IN NORTHWEST ONTARIO. ALTHOUGH DEEP MIXING EXISTED ON THAT MPX SOUNDING...THE HIGHER MID LEVEL MOISTURE ALLOWED FOR THE PRECIPITABLE WATER TO JUMP UP TO 0.93 INCHES AS OF 00Z...COMPARED TO 0.44 12 HOURS EARLIER. THUS...THERE IS SOME MOISTURE AHEAD OF THE FARGO SHORTWAVE. MODEL TRENDS FOR TODAY HAVE REALLY SHIFTED THE SHORTWAVE COMING INTO THE FORECAST AREA NORTH COMPARED TO THE 16.00Z CYCLE. MODEL CONSENSUS NOW SUGGESTS THAT THE SHORTWAVE NEAR FARGO ENDS UP CROSSING CLARK COUNTY AT 00Z TUESDAY...COMPARED TO SAY LA CROSSE. THIS HAS A BIG IMPACT ON PLACEMENT OF PRECIPITATION CHANCES. WITH THE SHORTWAVE TRACKING FARTHER NORTH TODAY...THE COLD FRONT ONLY DROPS SOUTH TO MAYBE THE I-94 CORRIDOR BY 00Z. COMBINATION OF LOW LEVEL CONVERGENCE ON THE FRONT...LOW TO MID LEVEL FRONTOGENESIS NORTH OF THE FRONT...THE APPROACH OF THE SHORTWAVE TO YIELD SOME DPVA AND DAYTIME HEATING SHOULD PROVE FAVORABLE FOR NUMEROUS SHOWERS ALONG/NORTH OF I-94. COULD EVEN SEE SOME ISOLATED/SCATTERED ACTIVITY SOUTH OF THERE TOWARDS I-90 VERY LATE IN THE DAY AS THE FRONTAL FORCING APPROACHES. DEEP MIXING AGAIN LOOKS LIKELY TODAY AHEAD OF THE APPROACHING FRONT. NAM/RAP SOUNDINGS SHOW POTENTIAL OF 7500-9500 FT AGL FROM CLARK COUNTY SOUTHWARD...WHICH RESULTS IN HIGHS IN THE LOW TO PERHAPS EVEN SOME MID 80S. THIS SHOULD ALLOW DEWPOINTS TO FALL INTO THE LOW TO MID 50S. COMBINATION OF THE TWO RESULTS IN 0-1KM MLCAPES OF 400-700 J/KG IN THE AREA ALONG/NORTH OF THE FRONT. ALTHOUGH THIS IS NOT MUCH...IT WILL BE ENOUGH TO BOTH ADD THUNDERSTORMS AND MAKE THE SHOWERS MORE VIGOROUS. FREEZING LEVELS ARE LOW...9500-1000 FT AGL AT 21Z WHICH COULD ALLOW FOR SOME HAIL...BUT THE MINIMAL CAPE WHICH IS TALL AND SKINNY MAY KEEP ANY HAIL SMALL. BIGGER CONCERN WILL LIKELY BE WIND GIVEN THE DEEP MIXING YIELDING DEEP INVERTED-V LOOKS ON A SKEW-T. COULD SEE STRONG TO SEVERE WIND GUSTS...JUST LIKE WHAT WENT THROUGH MINNEAPOLIS AROUND 00Z LAST EVENING. THE VIGOROUS CONVECTIVE ACTIVITY WILL LIKELY DIMINISH QUICKLY AFTER 00Z AS LOSS OF HEATING KNOCKS DOWN CAPE. HOWEVER... ISOLATED/SCATTERED SHOWER ACTIVITY MAY PERSIST THROUGH MUCH OF THE NIGHT AS THE FRONT SLOWLY SINKS SOUTH...AIDED BY LOW TO MID LEVEL FRONTOGENESIS PERSISTING ALONG/NORTH OF THE FRONT. ADDITIONALLY... AFTER MIDNIGHT TONIGHT...ATTENTION TURNS TO THE SHORTWAVE OVER SOUTHWEST SASKATCHEWAN. MODELS HAVE SPED UP THIS SHORTWAVE...PERHAPS MOVING INTO FAR WESTERN PORTIONS OF THE FORECAST AREA BY 12Z TUESDAY AS SUGGESTED BY THE 17.00Z GFS. 17.00Z NAM/UKMET ARE JUST SLIGHTLY SLOWER. IN ANY EVENT...DPVA AND A LOWERING TROPOPAUSE WITH THIS SHORTWAVE WILL LIKELY HELP STRENGTHEN THE LOW TO MID LEVEL FRONTOGENESIS IN PLACE ALONG/NORTH OF THE FRONT. THUS...THIS SHORTWAVE SHOULD HELP PROMOTE KEEPING ISOLATED/SCATTERED ACTIVITY GOING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 307 AM CDT MON JUN 17 2013 TUESDAY...ATTENTION IS ON THAT SHORTWAVE APPROACHING FAR WESTERN PORTIONS OF THE FORECAST AREA AT 12Z. AGAIN...WITH MODELS SPEEDING UP THE SHORTWAVE...THE WAVE PRETTY MUCH EXITS THE AREA BY 18Z...REACHING NORTHWEST INDIANA BY 00Z. MODELS HAVE COME INTO MUCH BETTER CONSENSUS ON WHETHER THIS SHORTWAVE WILL PRODUCE PRECIPITATION...WITH THE 17.00Z NAM/GFS/CANADIAN/UKMET/ECMWF AND HIRES NMM/ARW ALL NOW DEPICTING SOME LIGHT PRECIPITATION. BELIEVE THE REASON THE QPF IS LIGHT IS THAT THE MOISTURE TRANSPORT IS NOT ALL THAT GREAT...AND THE AVAILABLE MOISTURE IS SOMEWHAT LIMITED. HOWEVER...WITH ALL MODELS DEPICTING A FAIRLY STRONG SHORTWAVE PER 500MB PROGS...THE FORCING SHOULD BE ENOUGH TO SQUEEZE OUT SOME SHOWERS AND POSSIBLY EVEN A THUNDERSTORM OR TWO ONCE DAYTIME HEATING GETS GOING. THUS...HAVE ADDED 20-30 PERCENT CHANCES TO THE FORECAST...HIGHEST TUESDAY MORNING. THESE CHANCES MAY NEED TO BE INCREASED IN LATER FORECASTS. COMBINATION OF CLOUDS ACCOMPANYING THE SHORTWAVE AND A NORTHEAST LOW LEVEL FLOW OUT OF HIGH PRESSURE IN UPPER MICHIGAN WILL YIELD A COOLER DAY. HIGHS MOST LOCATIONS SHOULD END UP IN THE LOW TO MID 70S. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THE UPPER LOW OFF THE PACIFIC NORTHWEST IS PROGGED TO MOVE INLAND DURING THIS PERIOD...FORCING RIDGING TO INCREASE DOWNSTREAM OVER THE PLAINS. THIS SETUP WOULD PLACE THE FORECAST AREA IN SUBSIDENCE EAST OF THE RIDGE AXIS...FAVORABLE FOR HIGH PRESSURE AT THE SURFACE. THIS IS TRUE ACCORDING TO MODELS...AND WOULD NORMALLY SUGGEST A DRY FORECAST. HOWEVER...17.00Z NAM AND TO SOME DEGREE THE GFS THROW A MONKEY WRENCH INTO THIS PLAN...AS THESE MODELS SHOW A NORTH TO SOUTH ORIENTED SHORTWAVE BARRELING THROUGH THE RIDGE AND MOVING INTO THE AREA WEDNESDAY NIGHT. BOTH MODELS END UP BRINGING LIGHT PRECIPITATION INTO THE AREA. MEANWHILE...THE 17.00Z ECMWF/CANADIAN/UKMET SHOW A MUCH WEAKER REFLECTION OF THIS SHORTWAVE AS WELL AS SLOWER SPEED. AS A RESULT...THESE MODELS WOULD FAVOR THE PREVIOUS DRY FORECAST. HAVE STAYED WITH THE DRY FORECAST FOR NOW...BUT THIS SHORTWAVE WILL NEED SOME WATCHING. OTHERWISE...A COOL NIGHT LOOKS ON TAP TUESDAY NIGHT WITH THE HIGH PRESSURE AREA IN PLACE. SOME OF THE TYPICAL COLDER SPOTS COULD DROP INTO THE LOWER 40S. GRADUAL WARMING OF TEMPERATURES EXPECTED FOR HIGHS WEDNESDAY AND WEDNESDAY NIGHT WITH THE HIGH PRESSURE AREA SLOWLY DRIFTING OFF TO THE EAST...AS WELL AS AIRMASS MODIFICATION FROM DAYTIME HEATING TAKING PLACE. THURSDAY THROUGH THE WEEKEND... SIMPLY STATED...MORE SUMMER-LIKE WITH INCREASING HUMIDITY...DEALING WITH CAP CONCERNS AND POTENTIAL FOR MCSS. 17.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES CONTINUE TO SHOW GOOD RUN-TO-RUN CONSISTENCY ON THE UPPER LEVEL PATTERN. THE TROUGHING THAT HAS BEEN PERSISTENT IN SOUTHEAST CANADA IS PROGGED TO LIFT OUT BEGINNING ON THURSDAY. MEANWHILE THE UPPER LOW IN THE PACIFIC NORTHWEST SLOWLY EJECTS NORTHEAST INTO SOUTH CENTRAL CANADA ON SUNDAY. THE MOTIONS OF THE TWO TROUGHS ALLOW FOR A FAIRLY SUBSTANTIAL WARM/MOIST AIR ADVECTION TO TAKE PLACE ACROSS THE PLAINS AND TOWARDS THE FORECAST AREA. AS A RESULT...THE POTENTIAL EXISTS FOR MULTIPLE ROUNDS OF CONVECTION AS VARIOUS MCSS FORM. RUN-TO-RUN MODEL CONSISTENCY AS WELL AS AGREEMENT ON THE MCS TRACKS IS FAIRLY LOW...AND TO BE EXPECTED. THE ONLY WELL AGREED UPON MCS APPEARS TO BE ON FRIDAY INTO SATURDAY WHERE AN MCS FORMS OVER THE DAKOTAS AND TRACKS EAST INTO NORTHERN WI SAT MORNING. THUS...FOLLOWING A MODEL CONSENSUS FOR PRECIPITATION CHANCES YIELDS 40-60 PERCENT CHANCES ACROSS THE FORECAST AREA FOR SATURDAY...HIGHEST TOWARDS NORTHERN WI. THERE ARE INDICATIONS TOO THAT CAPPING WILL BE AN ISSUE TO CONTEND WITH AS 700MB TEMPS OVER 12C BEGIN ADVECTING TOWARDS THE AREA FOR THE WEEKEND. WE WILL DEFINITELY NEED TO WATCH FOR SEVERE WEATHER AND HEAVY RAIN HEADING INTO THE WEEKEND...GIVEN THE MCS POTENTIAL AND WARM CLOUD DEPTHS PROGGED IN THE 3500-4500 FT RANGE. TEMPERATURES ARE EXTREMELY TRICKY AS THEY DEPEND ON HOW CONVECTION EVOLVES...ESPECIALLY DAYTIME HIGHS. MODELS HAVE TRENDED WARMER FOR THURSDAY THROUGH THE WEEKEND...SO HAVE FOLLOWED SUIT AND RAISED HIGHS. HOWEVER...THESE MAY NEED FURTHER INCREASES IF SAY THE CURRENT 17.00Z ECMWF/GFS ARE CORRECT. THIS IS ESPECIALLY TRUE WHERE ON SATURDAY THEY BOOST 850MB TEMPS UP TO 20-24C...OR 2 STANDARD DEVIATIONS ABOVE NORMAL. HIGHS COULD EASILY CLIMB INTO THE LOW TO POSSIBLY EVEN MID 90S IF THIS COMES TRUE. EVAPOTRANSPORATION AND MOISTURE ADVECTION SHOULD HELP BOOST DEWPOINTS INTO THE 70S...WHICH THIS LATENT HEATING WILL KEEP HIGHS FROM GETTING MUCH HIGHER THAN THAT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1255 PM CDT MON JUN 17 2013 A WEAK COLD FRONT AND UPPER LEVEL DISTURBANCE DROPPING SOUTH ACROSS THE REGION THIS AFTERNOON THROUGH TONIGHT WILL BRING A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS TO THE TAF SITES. CONFIDENCE IS LOW ON THIS ACTIVITY IMPACTING THE TAF SITES...GIVEN THE ISOLATED NATURE...SO WILL HAVE TO MONITOR THE SHRA/TSRA ACTIVITY OVER NORTH CENTRAL/NORTHWEST WISCONSIN THIS AFTERNOON AS IT EDGES SOUTH TOWARD THE INTERSTATE 90 CORRIDOR. IF STORMS MAKE IT TO THE TAF SITES LATE THIS AFTERNOON INTO EARLY THIS EVENING...THEY WOULD BE CAPABLE OF PRODUCING GUSTING WIND OF 30 TO 40 KTS AND POSSIBLY SMALL HAIL. OTHERWISE...PLAN ON VFR CONDITIONS WITH SCATTERED TO BROKEN CUMULUS WITH CLOUD BASES IN THE 4500 TO 6000 FT RANGE. ISOLATED SHOWERS AND STORMS ARE POSSIBLE DURING THE OVERNIGHT HOURS...WITH THE BETTER CHANCES FOR THESE SOUTH AND WEST OF KLSE LATE...POSSIBLY IMPACTING KRST AFTER MIDNIGHT AS THE FRONT SAGS SOUTH. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM....AJ AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
637 AM CDT MON JUN 17 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 307 AM CDT MON JUN 17 2013 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...RIDGING BUILDING FROM NEW MEXICO INTO BRITISH COLUMBIA...AND TROUGHING OVER SOUTHEAST CANADA INTO THE EASTERN GREAT LAKES. WITHIN THE WEST-NORTHWEST FLOW...TWO SHORTWAVES OF NOTE WERE NEAR FARGO NORTH DAKOTA AND IN FAR SOUTHWEST SASKATCHEWAN. 700-850MB MOISTURE TRANSPORT AHEAD OF THE FARGO SHORTWAVE HELPING TO SUPPORT SOME HIGH BASED SHOWERS ALONG/NORTHEAST OF I-94. TALKING ABOUT HIGH BASED... 00Z MPX AND GRB SOUNDINGS BOTH DEPICTED MIXING UP TO 750MB...WITH DEEP INVERTED-V APPEARANCE BELOW. THIS DEEP MIXING ALLOWED FOR SHOWERS THAT MOVED THROUGH MPX AROUND RAOB RELEASE TIME TO PRODUCE WIND GUSTS OF 30-50KT. THESE SHOWERS WERE MORE VIGOROUS THEN THOSE OCCURRING NOW...PLUS THEY OCCURRED RIGHT AFTER PEAK HEATING WHEN MIXING WAS AT ITS MAXIMUM...ALLOWING FOR THE STRONG GUST POTENTIAL. OTHERWISE...SKIES ARE MOSTLY CLEAR OVER THE FORECAST AREA SOUTH OF A COLD FRONT EXTENDING FROM NORTHERN MN INTO NORTHERN LOWER MI. 850MB TEMPS AT 00Z AHEAD OF THE FRONT WERE 14-16C AT MPX...GRB AND DVN...COMPARED TO 4C BEHIND THE FRONT UP AT PICKLE LAKE IN NORTHWEST ONTARIO. ALTHOUGH DEEP MIXING EXISTED ON THAT MPX SOUNDING...THE HIGHER MID LEVEL MOISTURE ALLOWED FOR THE PRECIPITABLE WATER TO JUMP UP TO 0.93 INCHES AS OF 00Z...COMPARED TO 0.44 12 HOURS EARLIER. THUS...THERE IS SOME MOISTURE AHEAD OF THE FARGO SHORTWAVE. MODEL TRENDS FOR TODAY HAVE REALLY SHIFTED THE SHORTWAVE COMING INTO THE FORECAST AREA NORTH COMPARED TO THE 16.00Z CYCLE. MODEL CONSENSUS NOW SUGGESTS THAT THE SHORTWAVE NEAR FARGO ENDS UP CROSSING CLARK COUNTY AT 00Z TUESDAY...COMPARED TO SAY LA CROSSE. THIS HAS A BIG IMPACT ON PLACEMENT OF PRECIPITATION CHANCES. WITH THE SHORTWAVE TRACKING FARTHER NORTH TODAY...THE COLD FRONT ONLY DROPS SOUTH TO MAYBE THE I-94 CORRIDOR BY 00Z. COMBINATION OF LOW LEVEL CONVERGENCE ON THE FRONT...LOW TO MID LEVEL FRONTOGENESIS NORTH OF THE FRONT...THE APPROACH OF THE SHORTWAVE TO YIELD SOME DPVA AND DAYTIME HEATING SHOULD PROVE FAVORABLE FOR NUMEROUS SHOWERS ALONG/NORTH OF I-94. COULD EVEN SEE SOME ISOLATED/SCATTERED ACTIVITY SOUTH OF THERE TOWARDS I-90 VERY LATE IN THE DAY AS THE FRONTAL FORCING APPROACHES. DEEP MIXING AGAIN LOOKS LIKELY TODAY AHEAD OF THE APPROACHING FRONT. NAM/RAP SOUNDINGS SHOW POTENTIAL OF 7500-9500 FT AGL FROM CLARK COUNTY SOUTHWARD...WHICH RESULTS IN HIGHS IN THE LOW TO PERHAPS EVEN SOME MID 80S. THIS SHOULD ALLOW DEWPOINTS TO FALL INTO THE LOW TO MID 50S. COMBINATION OF THE TWO RESULTS IN 0-1KM MLCAPES OF 400-700 J/KG IN THE AREA ALONG/NORTH OF THE FRONT. ALTHOUGH THIS IS NOT MUCH...IT WILL BE ENOUGH TO BOTH ADD THUNDERSTORMS AND MAKE THE SHOWERS MORE VIGOROUS. FREEZING LEVELS ARE LOW...9500-1000 FT AGL AT 21Z WHICH COULD ALLOW FOR SOME HAIL...BUT THE MINIMAL CAPE WHICH IS TALL AND SKINNY MAY KEEP ANY HAIL SMALL. BIGGER CONCERN WILL LIKELY BE WIND GIVEN THE DEEP MIXING YIELDING DEEP INVERTED-V LOOKS ON A SKEW-T. COULD SEE STRONG TO SEVERE WIND GUSTS...JUST LIKE WHAT WENT THROUGH MINNEAPOLIS AROUND 00Z LAST EVENING. THE VIGOROUS CONVECTIVE ACTIVITY WILL LIKELY DIMINISH QUICKLY AFTER 00Z AS LOSS OF HEATING KNOCKS DOWN CAPE. HOWEVER... ISOLATED/SCATTERED SHOWER ACTIVITY MAY PERSIST THROUGH MUCH OF THE NIGHT AS THE FRONT SLOWLY SINKS SOUTH...AIDED BY LOW TO MID LEVEL FRONTOGENESIS PERSISTING ALONG/NORTH OF THE FRONT. ADDITIONALLY... AFTER MIDNIGHT TONIGHT...ATTENTION TURNS TO THE SHORTWAVE OVER SOUTHWEST SASKATCHEWAN. MODELS HAVE SPED UP THIS SHORTWAVE...PERHAPS MOVING INTO FAR WESTERN PORTIONS OF THE FORECAST AREA BY 12Z TUESDAY AS SUGGESTED BY THE 17.00Z GFS. 17.00Z NAM/UKMET ARE JUST SLIGHTLY SLOWER. IN ANY EVENT...DPVA AND A LOWERING TROPOPAUSE WITH THIS SHORTWAVE WILL LIKELY HELP STRENGTHEN THE LOW TO MID LEVEL FRONTOGENESIS IN PLACE ALONG/NORTH OF THE FRONT. THUS...THIS SHORTWAVE SHOULD HELP PROMOTE KEEPING ISOLATED/SCATTERED ACTIVITY GOING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 307 AM CDT MON JUN 17 2013 TUESDAY...ATTENTION IS ON THAT SHORTWAVE APPROACHING FAR WESTERN PORTIONS OF THE FORECAST AREA AT 12Z. AGAIN...WITH MODELS SPEEDING UP THE SHORTWAVE...THE WAVE PRETTY MUCH EXITS THE AREA BY 18Z...REACHING NORTHWEST INDIANA BY 00Z. MODELS HAVE COME INTO MUCH BETTER CONSENSUS ON WHETHER THIS SHORTWAVE WILL PRODUCE PRECIPITATION...WITH THE 17.00Z NAM/GFS/CANADIAN/UKMET/ECMWF AND HIRES NMM/ARW ALL NOW DEPICTING SOME LIGHT PRECIPITATION. BELIEVE THE REASON THE QPF IS LIGHT IS THAT THE MOISTURE TRANSPORT IS NOT ALL THAT GREAT...AND THE AVAILABLE MOISTURE IS SOMEWHAT LIMITED. HOWEVER...WITH ALL MODELS DEPICTING A FAIRLY STRONG SHORTWAVE PER 500MB PROGS...THE FORCING SHOULD BE ENOUGH TO SQUEEZE OUT SOME SHOWERS AND POSSIBLY EVEN A THUNDERSTORM OR TWO ONCE DAYTIME HEATING GETS GOING. THUS...HAVE ADDED 20-30 PERCENT CHANCES TO THE FORECAST...HIGHEST TUESDAY MORNING. THESE CHANCES MAY NEED TO BE INCREASED IN LATER FORECASTS. COMBINATION OF CLOUDS ACCOMPANYING THE SHORTWAVE AND A NORTHEAST LOW LEVEL FLOW OUT OF HIGH PRESSURE IN UPPER MICHIGAN WILL YIELD A COOLER DAY. HIGHS MOST LOCATIONS SHOULD END UP IN THE LOW TO MID 70S. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THE UPPER LOW OFF THE PACIFIC NORTHWEST IS PROGGED TO MOVE INLAND DURING THIS PERIOD...FORCING RIDGING TO INCREASE DOWNSTREAM OVER THE PLAINS. THIS SETUP WOULD PLACE THE FORECAST AREA IN SUBSIDENCE EAST OF THE RIDGE AXIS...FAVORABLE FOR HIGH PRESSURE AT THE SURFACE. THIS IS TRUE ACCORDING TO MODELS...AND WOULD NORMALLY SUGGEST A DRY FORECAST. HOWEVER...17.00Z NAM AND TO SOME DEGREE THE GFS THROW A MONKEY WRENCH INTO THIS PLAN...AS THESE MODELS SHOW A NORTH TO SOUTH ORIENTED SHORTWAVE BARRELING THROUGH THE RIDGE AND MOVING INTO THE AREA WEDNESDAY NIGHT. BOTH MODELS END UP BRINGING LIGHT PRECIPITATION INTO THE AREA. MEANWHILE...THE 17.00Z ECMWF/CANADIAN/UKMET SHOW A MUCH WEAKER REFLECTION OF THIS SHORTWAVE AS WELL AS SLOWER SPEED. AS A RESULT...THESE MODELS WOULD FAVOR THE PREVIOUS DRY FORECAST. HAVE STAYED WITH THE DRY FORECAST FOR NOW...BUT THIS SHORTWAVE WILL NEED SOME WATCHING. OTHERWISE...A COOL NIGHT LOOKS ON TAP TUESDAY NIGHT WITH THE HIGH PRESSURE AREA IN PLACE. SOME OF THE TYPICAL COLDER SPOTS COULD DROP INTO THE LOWER 40S. GRADUAL WARMING OF TEMPERATURES EXPECTED FOR HIGHS WEDNESDAY AND WEDNESDAY NIGHT WITH THE HIGH PRESSURE AREA SLOWLY DRIFTING OFF TO THE EAST...AS WELL AS AIRMASS MODIFICATION FROM DAYTIME HEATING TAKING PLACE. THURSDAY THROUGH THE WEEKEND... SIMPLY STATED...MORE SUMMER-LIKE WITH INCREASING HUMIDITY...DEALING WITH CAP CONCERNS AND POTENTIAL FOR MCSS. 17.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES CONTINUE TO SHOW GOOD RUN-TO-RUN CONSISTENCY ON THE UPPER LEVEL PATTERN. THE TROUGHING THAT HAS BEEN PERSISTENT IN SOUTHEAST CANADA IS PROGGED TO LIFT OUT BEGINNING ON THURSDAY. MEANWHILE THE UPPER LOW IN THE PACIFIC NORTHWEST SLOWLY EJECTS NORTHEAST INTO SOUTH CENTRAL CANADA ON SUNDAY. THE MOTIONS OF THE TWO TROUGHS ALLOW FOR A FAIRLY SUBSTANTIAL WARM/MOIST AIR ADVECTION TO TAKE PLACE ACROSS THE PLAINS AND TOWARDS THE FORECAST AREA. AS A RESULT...THE POTENTIAL EXISTS FOR MULTIPLE ROUNDS OF CONVECTION AS VARIOUS MCSS FORM. RUN-TO-RUN MODEL CONSISTENCY AS WELL AS AGREEMENT ON THE MCS TRACKS IS FAIRLY LOW...AND TO BE EXPECTED. THE ONLY WELL AGREED UPON MCS APPEARS TO BE ON FRIDAY INTO SATURDAY WHERE AN MCS FORMS OVER THE DAKOTAS AND TRACKS EAST INTO NORTHERN WI SAT MORNING. THUS...FOLLOWING A MODEL CONSENSUS FOR PRECIPITATION CHANCES YIELDS 40-60 PERCENT CHANCES ACROSS THE FORECAST AREA FOR SATURDAY...HIGHEST TOWARDS NORTHERN WI. THERE ARE INDICATIONS TOO THAT CAPPING WILL BE AN ISSUE TO CONTEND WITH AS 700MB TEMPS OVER 12C BEGIN ADVECTING TOWARDS THE AREA FOR THE WEEKEND. WE WILL DEFINITELY NEED TO WATCH FOR SEVERE WEATHER AND HEAVY RAIN HEADING INTO THE WEEKEND...GIVEN THE MCS POTENTIAL AND WARM CLOUD DEPTHS PROGGED IN THE 3500-4500 FT RANGE. TEMPERATURES ARE EXTREMELY TRICKY AS THEY DEPEND ON HOW CONVECTION EVOLVES...ESPECIALLY DAYTIME HIGHS. MODELS HAVE TRENDED WARMER FOR THURSDAY THROUGH THE WEEKEND...SO HAVE FOLLOWED SUIT AND RAISED HIGHS. HOWEVER...THESE MAY NEED FURTHER INCREASES IF SAY THE CURRENT 17.00Z ECMWF/GFS ARE CORRECT. THIS IS ESPECIALLY TRUE WHERE ON SATURDAY THEY BOOST 850MB TEMPS UP TO 20-24C...OR 2 STANDARD DEVIATIONS ABOVE NORMAL. HIGHS COULD EASILY CLIMB INTO THE LOW TO POSSIBLY EVEN MID 90S IF THIS COMES TRUE. EVAPOTRANSPORATION AND MOISTURE ADVECTION SHOULD HELP BOOST DEWPOINTS INTO THE 70S...WHICH THIS LATENT HEATING WILL KEEP HIGHS FROM GETTING MUCH HIGHER THAN THAT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 637 AM CDT MON JUN 17 2013 CLOUDS TODAY WILL GENERALLY BE LIMITED TO CIRRUS AND DIURNAL CUMULUS IN THE 5K-6K FT RANGE...IN A DEEPLY MIXED AIRMASS AHEAD OF A SLOWLY SOUTHWARD MOVING COLD FRONT. WITH THE MIXING...NORTHWEST WINDS OF AROUND 10KT...GUSTING TO AROUND 20KTS ACROSS THE HIGHER TERRAIN AREAS...EXPECTED FOR THE LATE MORNING AND AFTERNOON HOURS. AS THE FRONT APPROACHES THE TAF SITES LATER THIS AFTERNOON/EVENING...WDLY SCT SHRA/TSRA EXPECTED WITH THE FRONT. WITH THE LIMITED AREAL COVERAGE OF ANY SHRA/TSRA...LEFT MENTION OUT OF TAFS DURING THE AFTERNOON/EVENING HOURS UNTIL BETTER DETAILS OF ANY TIMING/COVERAGE EMERGE. AN UPPER LEVEL DISTURBANCE APPROACHES AND MOVES ACROSS THE AREA LATER TONIGHT/TUE MORNING. THIS COMBINED WITH THE FRONT IN THE AREA AND AN INCREASE OF LOWER TO MID LEVEL MOISTURE PRODUCES ANOTHER CHANCE OF SHRA/TSRA ACROSS THE TAF SITES. DID CARRY VCSH IN TAF AFTER 06-07Z AND CIGS IN THE 4K TO 5K FT RANGE IN RESPONSE TO THE INCREASE OF MOISTURE AND LIFT WITH THE APPROACHING DISTURBANCE. AT THIS TIME...TOO MUCH UNCERTAINTY ABOUT TIMING/COVERAGE TO INCLUDE A TSRA/CB MENTION LATE IN THE TAF PERIOD. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM....AJ AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
307 AM CDT MON JUN 17 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 307 AM CDT MON JUN 17 2013 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OFF THE PACIFIC NORTHWEST COAST...RIDGING BUILDING FROM NEW MEXICO INTO BRITISH COLUMBIA...AND TROUGHING OVER SOUTHEAST CANADA INTO THE EASTERN GREAT LAKES. WITHIN THE WEST-NORTHWEST FLOW...TWO SHORTWAVES OF NOTE WERE NEAR FARGO NORTH DAKOTA AND IN FAR SOUTHWEST SASKATCHEWAN. 700-850MB MOISTURE TRANSPORT AHEAD OF THE FARGO SHORTWAVE HELPING TO SUPPORT SOME HIGH BASED SHOWERS ALONG/NORTHEAST OF I-94. TALKING ABOUT HIGH BASED... 00Z MPX AND GRB SOUNDINGS BOTH DEPICTED MIXING UP TO 750MB...WITH DEEP INVERTED-V APPEARANCE BELOW. THIS DEEP MIXING ALLOWED FOR SHOWERS THAT MOVED THROUGH MPX AROUND RAOB RELEASE TIME TO PRODUCE WIND GUSTS OF 30-50KT. THESE SHOWERS WERE MORE VIGOROUS THEN THOSE OCCURRING NOW...PLUS THEY OCCURRED RIGHT AFTER PEAK HEATING WHEN MIXING WAS AT ITS MAXIMUM...ALLOWING FOR THE STRONG GUST POTENTIAL. OTHERWISE...SKIES ARE MOSTLY CLEAR OVER THE FORECAST AREA SOUTH OF A COLD FRONT EXTENDING FROM NORTHERN MN INTO NORTHERN LOWER MI. 850MB TEMPS AT 00Z AHEAD OF THE FRONT WERE 14-16C AT MPX...GRB AND DVN...COMPARED TO 4C BEHIND THE FRONT UP AT PICKLE LAKE IN NORTHWEST ONTARIO. ALTHOUGH DEEP MIXING EXISTED ON THAT MPX SOUNDING...THE HIGHER MID LEVEL MOISTURE ALLOWED FOR THE PRECIPITABLE WATER TO JUMP UP TO 0.93 INCHES AS OF 00Z...COMPARED TO 0.44 12 HOURS EARLIER. THUS...THERE IS SOME MOISTURE AHEAD OF THE FARGO SHORTWAVE. MODEL TRENDS FOR TODAY HAVE REALLY SHIFTED THE SHORTWAVE COMING INTO THE FORECAST AREA NORTH COMPARED TO THE 16.00Z CYCLE. MODEL CONSENSUS NOW SUGGESTS THAT THE SHORTWAVE NEAR FARGO ENDS UP CROSSING CLARK COUNTY AT 00Z TUESDAY...COMPARED TO SAY LA CROSSE. THIS HAS A BIG IMPACT ON PLACEMENT OF PRECIPITATION CHANCES. WITH THE SHORTWAVE TRACKING FARTHER NORTH TODAY...THE COLD FRONT ONLY DROPS SOUTH TO MAYBE THE I-94 CORRIDOR BY 00Z. COMBINATION OF LOW LEVEL CONVERGENCE ON THE FRONT...LOW TO MID LEVEL FRONTOGENESIS NORTH OF THE FRONT...THE APPROACH OF THE SHORTWAVE TO YIELD SOME DPVA AND DAYTIME HEATING SHOULD PROVE FAVORABLE FOR NUMEROUS SHOWERS ALONG/NORTH OF I-94. COULD EVEN SEE SOME ISOLATED/SCATTERED ACTIVITY SOUTH OF THERE TOWARDS I-90 VERY LATE IN THE DAY AS THE FRONTAL FORCING APPROACHES. DEEP MIXING AGAIN LOOKS LIKELY TODAY AHEAD OF THE APPROACHING FRONT. NAM/RAP SOUNDINGS SHOW POTENTIAL OF 7500-9500 FT AGL FROM CLARK COUNTY SOUTHWARD...WHICH RESULTS IN HIGHS IN THE LOW TO PERHAPS EVEN SOME MID 80S. THIS SHOULD ALLOW DEWPOINTS TO FALL INTO THE LOW TO MID 50S. COMBINATION OF THE TWO RESULTS IN 0-1KM MLCAPES OF 400-700 J/KG IN THE AREA ALONG/NORTH OF THE FRONT. ALTHOUGH THIS IS NOT MUCH...IT WILL BE ENOUGH TO BOTH ADD THUNDERSTORMS AND MAKE THE SHOWERS MORE VIGOROUS. FREEZING LEVELS ARE LOW...9500-1000 FT AGL AT 21Z WHICH COULD ALLOW FOR SOME HAIL...BUT THE MINIMAL CAPE WHICH IS TALL AND SKINNY MAY KEEP ANY HAIL SMALL. BIGGER CONCERN WILL LIKELY BE WIND GIVEN THE DEEP MIXING YIELDING DEEP INVERTED-V LOOKS ON A SKEW-T. COULD SEE STRONG TO SEVERE WIND GUSTS...JUST LIKE WHAT WENT THROUGH MINNEAPOLIS AROUND 00Z LAST EVENING. THE VIGOROUS CONVECTIVE ACTIVITY WILL LIKELY DIMINISH QUICKLY AFTER 00Z AS LOSS OF HEATING KNOCKS DOWN CAPE. HOWEVER... ISOLATED/SCATTERED SHOWER ACTIVITY MAY PERSIST THROUGH MUCH OF THE NIGHT AS THE FRONT SLOWLY SINKS SOUTH...AIDED BY LOW TO MID LEVEL FRONTOGENESIS PERSISTING ALONG/NORTH OF THE FRONT. ADDITIONALLY... AFTER MIDNIGHT TONIGHT...ATTENTION TURNS TO THE SHORTWAVE OVER SOUTHWEST SASKATCHEWAN. MODELS HAVE SPED UP THIS SHORTWAVE...PERHAPS MOVING INTO FAR WESTERN PORTIONS OF THE FORECAST AREA BY 12Z TUESDAY AS SUGGESTED BY THE 17.00Z GFS. 17.00Z NAM/UKMET ARE JUST SLIGHTLY SLOWER. IN ANY EVENT...DPVA AND A LOWERING TROPOPAUSE WITH THIS SHORTWAVE WILL LIKELY HELP STRENGTHEN THE LOW TO MID LEVEL FRONTOGENESIS IN PLACE ALONG/NORTH OF THE FRONT. THUS...THIS SHORTWAVE SHOULD HELP PROMOTE KEEPING ISOLATED/SCATTERED ACTIVITY GOING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 307 AM CDT MON JUN 17 2013 TUESDAY...ATTENTION IS ON THAT SHORTWAVE APPROACHING FAR WESTERN PORTIONS OF THE FORECAST AREA AT 12Z. AGAIN...WITH MODELS SPEEDING UP THE SHORTWAVE...THE WAVE PRETTY MUCH EXITS THE AREA BY 18Z...REACHING NORTHWEST INDIANA BY 00Z. MODELS HAVE COME INTO MUCH BETTER CONSENSUS ON WHETHER THIS SHORTWAVE WILL PRODUCE PRECIPITATION...WITH THE 17.00Z NAM/GFS/CANADIAN/UKMET/ECMWF AND HIRES NMM/ARW ALL NOW DEPICTING SOME LIGHT PRECIPITATION. BELIEVE THE REASON THE QPF IS LIGHT IS THAT THE MOISTURE TRANSPORT IS NOT ALL THAT GREAT...AND THE AVAILABLE MOISTURE IS SOMEWHAT LIMITED. HOWEVER...WITH ALL MODELS DEPICTING A FAIRLY STRONG SHORTWAVE PER 500MB PROGS...THE FORCING SHOULD BE ENOUGH TO SQUEEZE OUT SOME SHOWERS AND POSSIBLY EVEN A THUNDERSTORM OR TWO ONCE DAYTIME HEATING GETS GOING. THUS...HAVE ADDED 20-30 PERCENT CHANCES TO THE FORECAST...HIGHEST TUESDAY MORNING. THESE CHANCES MAY NEED TO BE INCREASED IN LATER FORECASTS. COMBINATION OF CLOUDS ACCOMPANYING THE SHORTWAVE AND A NORTHEAST LOW LEVEL FLOW OUT OF HIGH PRESSURE IN UPPER MICHIGAN WILL YIELD A COOLER DAY. HIGHS MOST LOCATIONS SHOULD END UP IN THE LOW TO MID 70S. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THE UPPER LOW OFF THE PACIFIC NORTHWEST IS PROGGED TO MOVE INLAND DURING THIS PERIOD...FORCING RIDGING TO INCREASE DOWNSTREAM OVER THE PLAINS. THIS SETUP WOULD PLACE THE FORECAST AREA IN SUBSIDENCE EAST OF THE RIDGE AXIS...FAVORABLE FOR HIGH PRESSURE AT THE SURFACE. THIS IS TRUE ACCORDING TO MODELS...AND WOULD NORMALLY SUGGEST A DRY FORECAST. HOWEVER...17.00Z NAM AND TO SOME DEGREE THE GFS THROW A MONKEY WRENCH INTO THIS PLAN...AS THESE MODELS SHOW A NORTH TO SOUTH ORIENTED SHORTWAVE BARRELING THROUGH THE RIDGE AND MOVING INTO THE AREA WEDNESDAY NIGHT. BOTH MODELS END UP BRINGING LIGHT PRECIPITATION INTO THE AREA. MEANWHILE...THE 17.00Z ECMWF/CANADIAN/UKMET SHOW A MUCH WEAKER REFLECTION OF THIS SHORTWAVE AS WELL AS SLOWER SPEED. AS A RESULT...THESE MODELS WOULD FAVOR THE PREVIOUS DRY FORECAST. HAVE STAYED WITH THE DRY FORECAST FOR NOW...BUT THIS SHORTWAVE WILL NEED SOME WATCHING. OTHERWISE...A COOL NIGHT LOOKS ON TAP TUESDAY NIGHT WITH THE HIGH PRESSURE AREA IN PLACE. SOME OF THE TYPICAL COLDER SPOTS COULD DROP INTO THE LOWER 40S. GRADUAL WARMING OF TEMPERATURES EXPECTED FOR HIGHS WEDNESDAY AND WEDNESDAY NIGHT WITH THE HIGH PRESSURE AREA SLOWLY DRIFTING OFF TO THE EAST...AS WELL AS AIRMASS MODIFICATION FROM DAYTIME HEATING TAKING PLACE. THURSDAY THROUGH THE WEEKEND... SIMPLY STATED...MORE SUMMER-LIKE WITH INCREASING HUMIDITY...DEALING WITH CAP CONCERNS AND POTENTIAL FOR MCSS. 17.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES CONTINUE TO SHOW GOOD RUN-TO-RUN CONSISTENCY ON THE UPPER LEVEL PATTERN. THE TROUGHING THAT HAS BEEN PERSISTENT IN SOUTHEAST CANADA IS PROGGED TO LIFT OUT BEGINNING ON THURSDAY. MEANWHILE THE UPPER LOW IN THE PACIFIC NORTHWEST SLOWLY EJECTS NORTHEAST INTO SOUTH CENTRAL CANADA ON SUNDAY. THE MOTIONS OF THE TWO TROUGHS ALLOW FOR A FAIRLY SUBSTANTIAL WARM/MOIST AIR ADVECTION TO TAKE PLACE ACROSS THE PLAINS AND TOWARDS THE FORECAST AREA. AS A RESULT...THE POTENTIAL EXISTS FOR MULTIPLE ROUNDS OF CONVECTION AS VARIOUS MCSS FORM. RUN-TO-RUN MODEL CONSISTENCY AS WELL AS AGREEMENT ON THE MCS TRACKS IS FAIRLY LOW...AND TO BE EXPECTED. THE ONLY WELL AGREED UPON MCS APPEARS TO BE ON FRIDAY INTO SATURDAY WHERE AN MCS FORMS OVER THE DAKOTAS AND TRACKS EAST INTO NORTHERN WI SAT MORNING. THUS...FOLLOWING A MODEL CONSENSUS FOR PRECIPITATION CHANCES YIELDS 40-60 PERCENT CHANCES ACROSS THE FORECAST AREA FOR SATURDAY...HIGHEST TOWARDS NORTHERN WI. THERE ARE INDICATIONS TOO THAT CAPPING WILL BE AN ISSUE TO CONTEND WITH AS 700MB TEMPS OVER 12C BEGIN ADVECTING TOWARDS THE AREA FOR THE WEEKEND. WE WILL DEFINITELY NEED TO WATCH FOR SEVERE WEATHER AND HEAVY RAIN HEADING INTO THE WEEKEND...GIVEN THE MCS POTENTIAL AND WARM CLOUD DEPTHS PROGGED IN THE 3500-4500 FT RANGE. TEMPERATURES ARE EXTREMELY TRICKY AS THEY DEPEND ON HOW CONVECTION EVOLVES...ESPECIALLY DAYTIME HIGHS. MODELS HAVE TRENDED WARMER FOR THURSDAY THROUGH THE WEEKEND...SO HAVE FOLLOWED SUIT AND RAISED HIGHS. HOWEVER...THESE MAY NEED FURTHER INCREASES IF SAY THE CURRENT 17.00Z ECMWF/GFS ARE CORRECT. THIS IS ESPECIALLY TRUE WHERE ON SATURDAY THEY BOOST 850MB TEMPS UP TO 20-24C...OR 2 STANDARD DEVIATIONS ABOVE NORMAL. HIGHS COULD EASILY CLIMB INTO THE LOW TO POSSIBLY EVEN MID 90S IF THIS COMES TRUE. EVAPOTRANSPORATION AND MOISTURE ADVECTION SHOULD HELP BOOST DEWPOINTS INTO THE 70S...WHICH THIS LATENT HEATING WILL KEEP HIGHS FROM GETTING MUCH HIGHER THAN THAT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1105 PM CDT SUN JUN 16 2013 A WEST-EAST RUNNING SFC BOUNDARY WILL SLOWLY SINK SOUTHWARD ON MONDAY...AIDED BY AN UPPER LEVEL SHORTWAVE SLIDING ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. THE BOUNDARY HOLDS MORE TO THE NORTH THOUGH UNTIL LATER MONDAY NIGHT WHEN A SECONDARY...STRONGER PIECE OF UPPER LEVEL ENERGY DIPS SOUTHEAST ACROSS THE REGION. INSTABILITY AND WEAK MOISTURE TRANSPORT MAKES THE BOUNDARY A PRIME PLACE FOR SOME SCATTERED SHRA/TS. ANY PCPN THAT DOES GET GOING WOULD HAVE THE CHANCE FOR ENHANCED GUSTINESS...WITH A DRY NEAR SFC LAYER DEPICTED IN BUFKIT SOUNDINGS FAVORING THE HIGHER GUST POTENTIAL. EXPECT VFR CONDITIONS FOR MONDAY INTO MONDAY NIGHT...WITH PCPN CHANCES LIKELY HOLDING OFF UNTIL MONDAY NIGHT - BETTER OVERNIGHT INTO EARLY TUE MORNING. WILL PUSH THE VCSH SHOWER MENTION PAST 00Z...BUT CONFIDENCE FOR A SHRA/TS IS FOR THE OVERNIGHT HOURS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1105 PM CDT SUN JUN 16 2013 .UPDATE...THIS EVENING ISSUED AT 609 PM CDT SUN JUN 16 2013 CONVECTION THAT FIRED UP ACROSS WESTERN MINNESOTA REMAINS INTACT AS IT HEADS INTO TWIN CITIES METRO AREA THIS EVENING. MSP AIRPORT GUSTED TO NEAR 60 MPH AS IT CAME THROUGH. RADAR RETURNS ARE NOT THAT IMPRESSIVE...HOWEVER ATMOSPHERIC CONDITIONS ARE CONDUCIVE FOR STRONG OUTFLOW GUSTS. RAP SOUNDINGS SHOW WELL MIXED LOW-LEVELS / UP TO 700 MB / AND STEEP LAPSE RATES. DRY AIR ENTRAINMENT IS ALSO HELPING TO PUT DOWN STRONG TO SEVERE WIND GUSTS. DCAPE IS BETWEEN 1000 TO 1500 J/KG AND THIS EXTENDS INTO PARTS OF SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. EXPECTING THIS COMPLEX TO CONTINUE OVER THE NEXT 2 TO 4 HOURS AND THE SEVERE WIND THREAT MAY PERSIST INTO PARTS OF THE AREA. AT THE VERY LEAST...EXPECTING 30 TO 40 MPH GUSTS. WILL CLOSELY MONITOR THE POTENTIAL FOR SEVERE GUSTS. && .SHORT TERM...(TONIGHT THROUGH WED NIGHT) ISSUED AT 219 PM CDT SUN JUN 16 2013 MINOR RAIN THREATS TO START THE WEEK SEEM LIKE THE MAIN FOCUS FOR THIS FORECAST WITH OTHERWISE FAIRLY QUIET FLOW. STUNNING FATHERS DAY IN PROGRESS WITH PLENTY OF SUN AND MUCH NEEDED DRYING. UNFORTUNATELY CANT KEEP RAIN OUT OF THE FORECAST LONG THESE DAYS AS SHORT WAVE TROUGHS APPROACH IN NORTHWEST FLOW. THESE WAVES ARE SPINNING OFF CLOSED UPPER LOW MOVING THROUGH SOUTHERN CANADA AND EVEN THOUGH THERE IS LESS MOISTURE TO WORK WITH...STILL SEEING CONVECTION UPSTREAM THAT COULD WORK INTO NORTH CENTRAL WISCONSIN AND EVENTUALLY FURTHER SOUTH INTO MONDAY. CIRRUS BLOWOFF FROM STORM COMPLEX OVER THE PLAINS WILL ALSO SWEEP THROUGH TONIGHT. OUTSIDE OF NEAR TERM...MODELS STRUGGLING WITH RESOLUTION OF THESE EMBEDDED WAVES BUT WITH POSSIBLE STRONGER ENERGY MONDAY...BOUNDARY AND PROXIMITY TO APPROACHING UPPER LOW...SHOWERS AND A FEW THUNDERSTORMS LOOK MORE LIKELY BY MONDAY AFTERNOON AND EVENING WITH MINOR MOST UNSTABLE CAPE. RAIN THAT DOES OCCUR SHOULD REMAIN SCATTERED AND PROGRESSIVE WITH MODEST NORTHWEST STEERING FLOW. EVEN THOUGH LAST IN SERIES OF SHORT WAVES COULD IMPACT AREA ON TUESDAY...DRYING AIRMASS AND SURFACE RIDGE SUGGESTS THIS COULD COUNTER ANY THREAT FOR ADDITIONAL SHOWERS. WILL KEEP DRY FORECAST RIDING SINCE CHANCES FOR RAIN TOO SMALL TO MENTION SO FAR. COOL AIRMASS WILL DIP TEMPERATURES INTO THE 40S IN CENTRAL WISCONSIN TUESDAY NIGHT WHERE FAVORED VALLEYS COULD SEE A LITTLE FOG. WARM AIR ADVECTION ALREADY RETURNS BY WEDNESDAY MORNING IN MINNESOTA AND IOWA BUT BULK OF RAIN SHOULD HOLD OFF UNTIL LATER IN WEEK AS ANY APPROACHING PRECIPITATION BATTLES DRIER AIR TO THE EAST. GRADUAL WARMING TREND ALSO TAKES PLACE AS HEIGHTS RISE. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 219 PM CDT SUN JUN 16 2013 NATIONAL DISCUSSION SUMMARIZED IT WELL WITH THE WORD MESSY REGARDING THE EXTENDED FORECAST. WHILE MEAN UPPER RIDGE OVER NATIONS MID SECTION GROWS INITIALLY...SHORT WAVES EJECTING OUT OF TROUGH OVER PACIFIC NORTHWEST WILL LEAD TO LOW LEVEL FORCING AND RETURN OF LOW LEVEL MOISTURE AND WARM AIR ADVECTION...ESPECIALLY TO THE WEST OF AREA. DRIER AIR TO THE EAST WILL BE SHUNTED OFF EVENTUALLY BUT COULD HOLD BULK OF RAIN THREAT OFF ON THURSDAY...BEFORE SPREADING ACROSS AREA WIDE BY FRIDAY. RIDGE FLATTENS QUITE A BIT BY NEXT WEEKEND AND WITH STRONGER SHORT WAVE ENERGY PASSING ACROSS NORTHERN TIER OF STATES COULD VERY WELL SEE SEVERAL PROGRESSIVE MESOSCALE CONVECTIVE SYSTEMS /MCS/. HARD TO PUT ANY IDEA OF TIMING SO GENERAL RAIN CHANCES OF 30 TO 40 PERCENT LOOK REASONABLE THIS FAR OUT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1105 PM CDT SUN JUN 16 2013 A WEST-EAST RUNNING SFC BOUNDARY WILL SLOWLY SINK SOUTHWARD ON MONDAY...AIDED BY AN UPPER LEVEL SHORTWAVE SLIDING ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. THE BOUNDARY HOLDS MORE TO THE NORTH THOUGH UNTIL LATER MONDAY NIGHT WHEN A SECONDARY...STRONGER PIECE OF UPPER LEVEL ENERGY DIPS SOUTHEAST ACROSS THE REGION. INSTABILITY AND WEAK MOISTURE TRANSPORT MAKES THE BOUNDARY A PRIME PLACE FOR SOME SCATTERED SHRA/TS. ANY PCPN THAT DOES GET GOING WOULD HAVE THE CHANCE FOR ENHANCED GUSTINESS...WITH A DRY NEAR SFC LAYER DEPICTED IN BUFKIT SOUNDINGS FAVORING THE HIGHER GUST POTENTIAL. EXPECT VFR CONDITIONS FOR MONDAY INTO MONDAY NIGHT...WITH PCPN CHANCES LIKELY HOLDING OFF UNTIL MONDAY NIGHT - BETTER OVERNIGHT INTO EARLY TUE MORNING. WILL PUSH THE VCSH SHOWER MENTION PAST 00Z...BUT CONFIDENCE FOR A SHRA/TS IS FOR THE OVERNIGHT HOURS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE.......ZT SHORT TERM...SHEA LONG TERM....SHEA AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
947 PM MDT TUE JUN 18 2013 .UPDATE... ISSUED AT 946 PM MDT TUE JUN 18 2013 THE THUNDERSTORMS OVER THE CWA CONTINUE TO MOVE EAST AHEAD OF THE SHORTWAVE TROUGH AND WERE OVER THE FAR EAST PART OF THE CWA. MEANWHILE...A BOUNDARY OVER THE FAR SOUTH PART OF THE CWA HAS AIDED IN THE FORMATION OF ADDITIONAL THUNDERSTORMS FROM NEAR KCYS TO KIBM LATE THIS EVENING. THE ACTIVITY IN THOSE AREAS SHOULD SLOWLY WEAKEN AND CONTINUE INTO EARLY WEDNESDAY MORNING. IN A RECENT UPDATE HAVE MADE MINOR CHANGES TO THE FIRST PERIOD OF THE FORECAST. UPDATE ISSUED AT 733 PM MDT TUE JUN 18 2013 THUNDERSTORMS HAVE BEEN WEAKENING OVER THE PANHANDLE SINCE 01Z. THE ACTIVITY CONTINUES TO BE PUSHED EAST AHEAD OF A SHORTWAVE TROUGH. THAT FEATURE SHOULD BE EAST OF THE CWA BY 04Z. HAVE KEPT STRONG THUNDERSTORMS OVER MAINLY THE EAST PART OF THE PANHANDLE UNTIL THAT TIME. OTHERWISE...CLEARING WILL CONTINUE FROM WEST TO EAST OVER THE CWA. MADE ADJUSTMENTS TO THE POPS FOR EARLY TONIGHT AND MINOR CHANGES TO THE REMAINDER OF THE FORECAST FOR TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 230 PM MDT TUE JUN 18 2013 FORECAST CHALLENGES DEAL WITH SEVERE THUNDERSTORM CHANCES TODAY...FOLLOWED BY FIRE WEATHER CONCERNS THROUGH FRIDAY. PLEASE REFER TO FIRE WEATHER SECTION BELOW FOR FIRE WEATHER DETAILS. CURRENTLY...CONVECTION BEGINNING TO DEVELOP OUT WEST OF THE LARAMIE RANGE. LATEST WATER VAPOR IMAGERY SHOWING A SUBTLE SHORTWAVE MOVING INTO SOUTHWESTERN WYOMING THIS AFTERNOON...WHICH IS MOST LIKELY AIDING IN EARLIER DEVELOPMENT OF TSTMS OUT WEST. A PRETTY MOIST ATMOSPHERE IN PLACE EAST OF THE LARAMIE RANGE WITH DEWPOINTS IN THE UPPER 40S JUST EAST OF THE LARAMIE RANGE HERE AT CHEYENNE. FURTHER EAST IN THE PANHANDLE...LOW TO MID 50 TDS ARE BEING REPORTED. LATEST SPC MESOANALYSIS SHOWING CAPES OVER EXTREME SOUTHEASTERN WYOMING AND SOUTHERN PANHANDLE AROUND 600-1000 J/KG AND CONVECTIVE INHIBITION AT ZERO. STILL CAPPED SOME OVER THE NORTHERN PANHANDLE AND NIOBRARA COUNTIES WITH ROUGHLY 50-75 J/KG...BUT THIS SHOULD ERODE AWAY AS TEMPERATURES CONTINUE TO CLIMB THIS AFTERNOON. THINKING A REPEAT OF YESTERDAY CONVECTION WISE...THOUGH COULD BE MORE WIDESPREAD WITH THE ASSISTANCE OF THAT LITTLE SHORTWAVE MOVING THROUGH THE AREA. SEVERE THUNDERSTORMS SHOULD MOVE OFF THE LARAMIE RANGE INTO THE BETTER ENVIRONMENT TO PRODUCE LARGE HAIL AND DAMAGING WINDS. SHORTWAVE COMES THROUGH EASTERN WYOMING BY 00Z THIS AFTERNOON. LATEST HRRR COMPOSITE REFLECTIVITY SHOWING INDIVIDUAL CELLS DEVELOPING OVER THE LARAMIE RANGE...THEN CONGEALING INTO A LINE NEAR THE WYOMING/NEBRASKA BORDER AFTER 00Z. THUNDERSTORMS LOOK TO COME TO AN END MID EVENING AS THE SHORTWAVE MOVES EAST INTO WESTERN NEBRASKA AFTER 03Z OR SO. UPPER RIDGE AXIS SHIFTS EAST AS WELL...WITH WEST TO SOUTHWEST WINDS RETURNING TO CARBON AND ALBANY COUNTIES AFTER MIDNIGHT. WEDNESDAY LOOKS LIKE A VERY DRY AND WINDY DAY AS 700MB WINDS INCREASE SIGNIFICANTLY. GFS SHOWING THESE WINDS CLIMBING TO NEAR 40KTS WEST OF THE LARAMIE RANGE. GOOD MID LEVEL WARMING AS WELL WITH 700MB TEMPERATURES CLIMBING FROM +10C THIS AFTERNOON TO +16C WEDNESDAY AFTERNOON. LEESIDE TROUGH STILL HANGS OUT OVER THE PANHANDLE WEDNESDAY AFTERNOON...SO ISOLATED TO WIDELY SCATTERED THUNDERSTORMS STILL A GOOD BET OUT THAT WAY. FOR THURSDAY...UPPER LOW CURRENTLY OFF THE WASHINGTON STATE COAST MOVES INLAND TO THE IDAHO PANHANDLE. THIS WILL KEEP WINDS STRONG OVER OUR CWFA...BUT 700MB TEMPERATURES COOL SOME...DOWN TO +10 TO +12C. SO THURSDAY SHOULD BE A LITTLE COOLER OVER WEDNESDAY BY A FEW DEGREES. .LONG TERM...(FRIDAY THROUGH TUESDAY) ISSUED AT 230 PM MDT TUE JUN 18 2013 REX BLOCKING PATTERN ACROSS WESTERN NOAM WILL BREAK DOWN EARLY IN THE PERIOD AS THE MEANDERING PACNW CLOSED LOW FILLS AND MOVES OUT ONTO THE NRN ROCKIES/PLAINS. THE DEPTH AT WHICH IT DOES SO WILL BE THE MAIN FORECAST CHALLENGE AND WILL CARRY RESIDUAL IMPACTS TO SENSIBLE WEATHER. ON FRIDAY...UPPER LOW WILL SWING FROM THE IDAHO PANHANDLE INTO WESTERN MONTANA. 12Z OPERATIONAL GFS AND ECMWF ARE FAIRLY SIMILAR IN ITS PLACEMENT NR THE ID/MT STATELINE BY EARLY SATURDAY. WEAK INSTABILITY ACROSS EAST CENTRAL WYOMING AND THE NORTHERN NEBRASKA PANHANDLE. SO HAVE CONFINED CONVECTIVE CHANCES THERE. THIS LOW PRESSURE AREA WILL SWING THROUGH MONTANA DURING THE DAY ON SATURDAY. THE EASTERN PLAINS SHOULD SEE ANOTHER CONVECTIVE DAY ON SATURDAY AS LLVL MOISTURE DEEPENS AND BACKS UP INTO THE EASTERN PLAINS. THIS WILL RESULT IN CAPE VALUES THAT WILL ONCE AGAIN CLIMB ABOVE 2000 J/KG. SATURDAY LOOKS TO PROVIDE THE BEST SEVERE WEATHER POTENTIAL THROUGH THE PERIOD. BY SUNDAY AND MONDAY...THE UPPER LOW EJECTS FROM THE DAKOTAS NORTHEAST TOWARDS HUDSON BAY. THIS SHOULD BRING AN END TO CONVECTIVE ACTIVITY AND BEGIN TO HEIGHTEN FIRE WEATHER CONCERNS FOR LATE IN THE WEEKEND/EARLY NEXT WEEK. FLOW WILL BECOME INCREASINGLY SOUTHWESTERLY AS WELL...WHICH WILL AID IN THE SURFACING OF GUSTIER WINDS ALOFT. H7 TEMPERATURES WILL RANGE BETWEEN 13 AND 15C THROUGH THE UPCOMING WEEKEND AND INCREASE TO 17C BY TUESDAY. HIGH TEMPERATURES WILL REACH GENERALLY IN THE 80S AND LOW 90S THROUGH THE PERIOD...WITH EVEN SOME MID AND POTENTIALLY UPPER 90S OUT ON THE FAR EASTERN PLAINS BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING) ISSUED AT 947 PM MDT TUE JUN 18 2013 THUNDERSTORMS WILL AFFECT THE FAR EAST AND FAR SOUTH PARTS OF THE CWA THROUGH 08Z. SOME OF STORMS WILL PRODUCE PERIODS OF MVFR CEILINGS AND VISIBILITIES IN RAIN AS WELL AS WIND GUSTS AS HIGH AS 40 KNOTS. OTHERWISE VFR CONDITIONS WILL BE COMMON THROUGH FRIDAY. WEST TO SOUTHWEST SURFACE WINDS WILL GUST AS HIGH AS 40 KNOTS MAINLY DURING THE DAYTIME HOURS IN AREAS ALONG AND WEST OF THE LARAMIE RANGE WEDNESDAY THROUGH FRIDAY. && .FIRE WEATHER... ISSUED AT 230 PM MDT TUE JUN 18 2013 ELEVATED TO LOCALLY CRITICAL FIRE WEATHER CONDITIONS WEDNESDAY THROUGH FRIDAY AS HIGH PRESSURE MOVES OFF TO THE EAST AND SOUTHWEST TO WEST WINDS RETURN TO THE AREA. ZONES ALONG AND WEST OF THE LARAMIE RANGE LOOK TO SEE WIDESPREAD WINDS OF 20 TO 30 MPH SUSTAINED WITH GUSTS TO 40 MPH BEGINNING MID MORNING WEDNESDAY THAT WILL PERSIST THROUGH FRIDAY. WINDIEST TIME PERIODS LOOK TO BE LATE MORNING THROUGH SUNSET. AFTERNOON HUMIDITIES OUT WEST WILL FALL TO 5 TO 10 PERCENT WITH POOR OVERNIGHT RECOVERIES WITH THESE STRONG WINDS. EAST OF THE LARAMIE RANGE...WINDS WILL BE LESS WITH HIGHER AFTERNOON HUMIDITIES. SINCE ALL ZONES ARE STILL REPORTING FUELS AS NOT READY FOR RAPID FIRE GROWTH...NO FIRE WEATHER HEADLINES ARE FORECAST FOR TOMORROW OR FRIDAY AT THIS TIME. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...WEILAND SHORT TERM...CLAYCOMB LONG TERM...HAHN AVIATION...WEILAND FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
734 PM MDT TUE JUN 18 2013 .UPDATE... ISSUED AT 733 PM MDT TUE JUN 18 2013 THUNDERSTORMS HAVE BEEN WEAKENING OVER THE PANHANDLE SINCE 01Z. THE ACTIVITY CONTINUES TO BE PUSHED EAST AHEAD OF A SHORTWAVE TROUGH. THAT FEATURE SHOULD BE EAST OF THE CWA BY 04Z. HAVE KEPT STRONG THUNDERSTORMS OVER MAINLY THE EAST PART OF THE PANHANDLE UNTIL THAT TIME. OTHERWISE...CLEARING WILL CONTINUE FROM WEST TO EAST OVER THE CWA. MADE ADJUSTMENTS TO THE POPS FOR EARLY TONIGHT AND MINOR CHANGES TO THE REMAINDER OF THE FORECAST FOR TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 230 PM MDT TUE JUN 18 2013 FORECAST CHALLENGES DEAL WITH SEVERE THUNDERSTORM CHANCES TODAY...FOLLOWED BY FIRE WEATHER CONCERNS THROUGH FRIDAY. PLEASE REFER TO FIRE WEATHER SECTION BELOW FOR FIRE WEATHER DETAILS. CURRENTLY...CONVECTION BEGINNING TO DEVELOP OUT WEST OF THE LARAMIE RANGE. LATEST WATER VAPOR IMAGERY SHOWING A SUBTLE SHORTWAVE MOVING INTO SOUTHWESTERN WYOMING THIS AFTERNOON...WHICH IS MOST LIKELY AIDING IN EARLIER DEVELOPMENT OF TSTMS OUT WEST. A PRETTY MOIST ATMOSPHERE IN PLACE EAST OF THE LARAMIE RANGE WITH DEWPOINTS IN THE UPPER 40S JUST EAST OF THE LARAMIE RANGE HERE AT CHEYENNE. FURTHER EAST IN THE PANHANDLE...LOW TO MID 50 TDS ARE BEING REPORTED. LATEST SPC MESOANALYSIS SHOWING CAPES OVER EXTREME SOUTHEASTERN WYOMING AND SOUTHERN PANHANDLE AROUND 600-1000 J/KG AND CONVECTIVE INHIBITION AT ZERO. STILL CAPPED SOME OVER THE NORTHERN PANHANDLE AND NIOBRARA COUNTIES WITH ROUGHLY 50-75 J/KG...BUT THIS SHOULD ERODE AWAY AS TEMPERATURES CONTINUE TO CLIMB THIS AFTERNOON. THINKING A REPEAT OF YESTERDAY CONVECTION WISE...THOUGH COULD BE MORE WIDESPREAD WITH THE ASSISTANCE OF THAT LITTLE SHORTWAVE MOVING THROUGH THE AREA. SEVERE THUNDERSTORMS SHOULD MOVE OFF THE LARAMIE RANGE INTO THE BETTER ENVIRONMENT TO PRODUCE LARGE HAIL AND DAMAGING WINDS. SHORTWAVE COMES THROUGH EASTERN WYOMING BY 00Z THIS AFTERNOON. LATEST HRRR COMPOSITE REFLECTIVITY SHOWING INDIVIDUAL CELLS DEVELOPING OVER THE LARAMIE RANGE...THEN CONGEALING INTO A LINE NEAR THE WYOMING/NEBRASKA BORDER AFTER 00Z. THUNDERSTORMS LOOK TO COME TO AN END MID EVENING AS THE SHORTWAVE MOVES EAST INTO WESTERN NEBRASKA AFTER 03Z OR SO. UPPER RIDGE AXIS SHIFTS EAST AS WELL...WITH WEST TO SOUTHWEST WINDS RETURNING TO CARBON AND ALBANY COUNTIES AFTER MIDNIGHT. WEDNESDAY LOOKS LIKE A VERY DRY AND WINDY DAY AS 700MB WINDS INCREASE SIGNIFICANTLY. GFS SHOWING THESE WINDS CLIMBING TO NEAR 40KTS WEST OF THE LARAMIE RANGE. GOOD MID LEVEL WARMING AS WELL WITH 700MB TEMPERATURES CLIMBING FROM +10C THIS AFTERNOON TO +16C WEDNESDAY AFTERNOON. LEESIDE TROUGH STILL HANGS OUT OVER THE PANHANDLE WEDNESDAY AFTERNOON...SO ISOLATED TO WIDELY SCATTERED THUNDERSTORMS STILL A GOOD BET OUT THAT WAY. FOR THURSDAY...UPPER LOW CURRENTLY OFF THE WASHINGTON STATE COAST MOVES INLAND TO THE IDAHO PANHANDLE. THIS WILL KEEP WINDS STRONG OVER OUR CWFA...BUT 700MB TEMPERATURES COOL SOME...DOWN TO +10 TO +12C. SO THURSDAY SHOULD BE A LITTLE COOLER OVER WEDNESDAY BY A FEW DEGREES. .LONG TERM...(FRIDAY THROUGH TUESDAY) ISSUED AT 230 PM MDT TUE JUN 18 2013 REX BLOCKING PATTERN ACROSS WESTERN NOAM WILL BREAK DOWN EARLY IN THE PERIOD AS THE MEANDERING PACNW CLOSED LOW FILLS AND MOVES OUT ONTO THE NRN ROCKIES/PLAINS. THE DEPTH AT WHICH IT DOES SO WILL BE THE MAIN FORECAST CHALLENGE AND WILL CARRY RESIDUAL IMPACTS TO SENSIBLE WEATHER. ON FRIDAY...UPPER LOW WILL SWING FROM THE IDAHO PANHANDLE INTO WESTERN MONTANA. 12Z OPERATIONAL GFS AND ECMWF ARE FAIRLY SIMILAR IN ITS PLACEMENT NR THE ID/MT STATELINE BY EARLY SATURDAY. WEAK INSTABILITY ACROSS EAST CENTRAL WYOMING AND THE NORTHERN NEBRASKA PANHANDLE. SO HAVE CONFINED CONVECTIVE CHANCES THERE. THIS LOW PRESSURE AREA WILL SWING THROUGH MONTANA DURING THE DAY ON SATURDAY. THE EASTERN PLAINS SHOULD SEE ANOTHER CONVECTIVE DAY ON SATURDAY AS LLVL MOISTURE DEEPENS AND BACKS UP INTO THE EASTERN PLAINS. THIS WILL RESULT IN CAPE VALUES THAT WILL ONCE AGAIN CLIMB ABOVE 2000 J/KG. SATURDAY LOOKS TO PROVIDE THE BEST SEVERE WEATHER POTENTIAL THROUGH THE PERIOD. BY SUNDAY AND MONDAY...THE UPPER LOW EJECTS FROM THE DAKOTAS NORTHEAST TOWARDS HUDSON BAY. THIS SHOULD BRING AN END TO CONVECTIVE ACTIVITY AND BEGIN TO HEIGHTEN FIRE WEATHER CONCERNS FOR LATE IN THE WEEKEND/EARLY NEXT WEEK. FLOW WILL BECOME INCREASINGLY SOUTHWESTERLY AS WELL...WHICH WILL AID IN THE SURFACING OF GUSTIER WINDS ALOFT. H7 TEMPERATURES WILL RANGE BETWEEN 13 AND 15C THROUGH THE UPCOMING WEEKEND AND INCREASE TO 17C BY TUESDAY. HIGH TEMPERATURES WILL REACH GENERALLY IN THE 80S AND LOW 90S THROUGH THE PERIOD...WITH EVEN SOME MID AND POTENTIALLY UPPER 90S OUT ON THE FAR EASTERN PLAINS BY EARLY NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY AFTERNOON) ISSUED AT 733 PM MDT TUE JUN 18 2013 STRONG THUNDERSTORMS WILL AFFECT THE EASTERN PANHANDLE THROUGH THE EVENING. THOSE STORMS WILL PRODUCE PERIODS OF MVFR CEILINGS AND VISIBILITIES IN RAIN AS WELL AS WIND GUSTS AS HIGH AS 40 KNOTS. OTHERWISE VFR CONDITIONS WILL BE COMMON THROUGH FRIDAY. WEST TO SOUTHWEST SURFACE WINDS WILL GUST AS HIGH AS 40 KNOTS MAINLY DURING THE DAYTIME HOURS IN AREAS ALONG AND WEST OF THE LARAMIE RANGE WEDNESDAY THROUGH FRIDAY. && .FIRE WEATHER... ISSUED AT 230 PM MDT TUE JUN 18 2013 ELEVATED TO LOCALLY CRITICAL FIRE WEATHER CONDITIONS WEDNESDAY THROUGH FRIDAY AS HIGH PRESSURE MOVES OFF TO THE EAST AND SOUTHWEST TO WEST WINDS RETURN TO THE AREA. ZONES ALONG AND WEST OF THE LARAMIE RANGE LOOK TO SEE WIDESPREAD WINDS OF 20 TO 30 MPH SUSTAINED WITH GUSTS TO 40 MPH BEGINNING MID MORNING WEDNESDAY THAT WILL PERSIST THROUGH FRIDAY. WINDIEST TIME PERIODS LOOK TO BE LATE MORNING THROUGH SUNSET. AFTERNOON HUMIDITIES OUT WEST WILL FALL TO 5 TO 10 PERCENT WITH POOR OVERNIGHT RECOVERIES WITH THESE STRONG WINDS. EAST OF THE LARAMIE RANGE...WINDS WILL BE LESS WITH HIGHER AFTERNOON HUMIDITIES. SINCE ALL ZONES ARE STILL REPORTING FUELS AS NOT READY FOR RAPID FIRE GROWTH...NO FIRE WEATHER HEADLINES ARE FORECAST FOR TOMORROW OR FRIDAY AT THIS TIME. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...WEILAND SHORT TERM...CLAYCOMB LONG TERM...HAHN AVIATION...WEILAND FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS RIVERTON WY
240 PM MDT MON JUN 17 2013 .SHORT TERM...TONIGHT THROUGH TUESDAY SHOWERS AND THUNDERSTORMS HAVE BEGUN TO DEVELOP ACROSS THE MOUNTAINOUS AREAS OF THE FORECAST AREA THIS AFTERNOON. SOME STORMS HAVE BEGUN TO MOVE INTO THEIR ADJACENT VALLEYS AND BASINS...MAINLY ACROSS THE UPPER GREEN RIVER BASIN AND JOHNSON COUNTY. ADDITIONAL STORM ACTIVITY IS ANTICIPATED THROUGH THE AFTERNOON...AND SHOULD LINGER INTO THE EARLY EVENING HOURS. ACTIVITY WILL WANE WITH THE LOSS OF DAYLIGHT THIS EVENING...BUT ACTIVITY WILL LINGER OVER THE CENTRAL AND NORTHERN MOUNTAINS. ANOTHER...STRONGER DISTURBANCE WILL MOVE OVER THE FORECAST AREA TUESDAY AFTERNOON. STORMS ARE ANTICIPATED TO START DURING THE EARLY AFTERNOON HOURS. SOME STORMS WILL SEE THE POTENTIAL TO BECOME STRONG...ESPECIALLY DURING THE LATER AFTERNOON HOURS. STRONGER THUNDERSTORMS MAY SEE THE POTENTIAL FOR VERY STRONG WIND GUSTS AND LARGER HAIL. THESE STRONGER STORMS SEEM MOST FAVORABLE ACROSS JOHNSON COUNTY...BUT THE EXTENT OF STRONGER STORM COVERAGE MAY NOT BE REALIZED UNTIL LATE MORNING TUESDAY. TEMPERATURES WILL WARM ACROSS THE AREA TUESDAY...WITH RELATIVE HUMIDITY AGAIN DECREASING TO THE SINGLE DIGITS ACROSS SOUTHERN WYOMING. WIND WILL INCREASE SOMEWHAT DURING THE AFTERNOON...BUT ARE NOT EXPECTED TO BE SIGNIFICANT ACROSS THE BULK OF THE AREA. THE EXCEPTION MIGHT BE SOUTHEASTERN SWEETWATER COUNTY. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY NIGHT THE THUNDERSTORMS OF TUESDAY AFTERNOON LOOK TO CONTINUE INTO TUESDAY EVENING BEFORE SLOWLY WANING WITH THE LOSS OF DAYTIME HEATING AND DRIER AIR PUNCHING IN FROM THE WEST AND SOUTH. MADE FEW CHANGES TO THE PLACEMENT OF THE STORMS WITH ACTIVITY MAINLY NORTH OF THE WIND RIVER RANGE...CLOSELY FOLLOWING THE 0.50 PRECIPITABLE WATER LINE. ON WEDNESDAY ACTIVITY LOOKS TO BE LESS THAN ON TUESDAY WITH MODELS SHOWING MUCH DRIER AIR IN PLACE ACROSS THE COUNTY WARNING AREA WITH PRECIPITABLE WATER VALUES FALLING TO UNDER 0.50 FOR ALL AREAS. ANY CONVECTION WOULD LIKELY BE LIMITED TO NORTHWESTERN WYOMING WHERE THERE WILL BE A BIT MORE MOISTURE TO WORK WITH AND SOMEWHAT MORE INSTABILITY DUE TO A CLOSER PROXIMITY TO AN UPPER LEVEL LOW OVER IDAHO. WITH A COLD FRONT APPROACHING AND MOVING THROUGH...THE PRESSURE GRADIENT WILL TIGHTEN UP A BIT AND BRING SOME GUSTY WINDS ACROSS AREAS EAST OF THE DIVIDE...ESPECIALLY ACROSS THE SOUTHWESTERN WIND CORRIDOR FROM THE RED DESERT THROUGH ROCK SPRINGS. IT DOES NOT LOOK LIKE HIGH WIND SINCE 700 MILLIBAR WINDS ARE NOT STRONG ENOUGH...BUT SOME WIND GUSTS TO 40 TO 50 MPH ARE CERTAINLY POSSIBLE. THERE COULD BE SOME ELEVATED FIRE DANGER IN THE AFTERNOON WITH RELATIVE HUMIDITY FALLING BELOW 10 PERCENT BUT NO RED FLAGS AT THIS TIME SINCE FUELS ARE NOT CRITICAL YET. THE DOWNSLOPING WIND WILL BRING A WARM DAY WITH SOME BASINS SEEING HIGHS AROUND 90. LITTLE CONVECTION IS EXPECTED EAST OF THE DIVIDE EXCEPT IN THE HIGHER ELEVATIONS. COOLER AIR WILL ADVECT IN BEHIND THE FRONT FOR WEDNESDAY NIGHT. IT COULD GET QUITE CHILLY IN THE WESTERN VALLEYS...WITH EVEN SOME PATCHY FROST IN THE MORE PROTECTED SPOTS. THURSDAY LOOKS TO BE A COOLER DAY BEHIND THE FRONT WITH LESS WIND AS WELL. AS FOR ANY CHANCE OF CONVECTION...WE CAN NOT RULE SOMETHING OUT IN THE FAR NORTHWEST BUT MOISTURE WILL BE LACKING SO FOR WE TRIMMED POPS A BIT ACROSS NORTHERN WYOMING AND KEPT ANY ACTIVITY DOWN TO SLIGHT CHANCE. AS A SIDE NOTE...THE SUMMER SOLSTICE IS AT 11:04 PM ON THURSDAY NIGHT SO THAT IS WHEN SUMMER ARRIVES. AND NOW...TO CELEBRATE THE FIRST FULL DAY OF SUMMER...WE PRESENT THE DISCUSSION OF FRIDAY WITH THE METEOROLOGICAL VERSION OF THE CLASSIC OLD SCHOOL RAP SONG SUMMERTIME. SO...DRUMS PLEASE. HERE IT IS...A PATTERN SLIGHTLY TRANSFORMED A BIT OF A BREAK FROM THE LATE SPRING NORM JUST A LITTLE WEATHER TO BREAK THE MONOTONY OF ALL THE STRONG STORMS THAT HAVE GOTTEN TO BE A LITTLE BIT OUT OF CONTROL AS THE DAY STARTS OFF COOL BUT ENDS UP WARM ENOUGH TO GO SWIMMING AT THE POOL GIVE ME A NICE GENTLE BREEZE JUST ENOUGH TO RUFFLE THE LEAVES ON THE TREES AND JUST LIKE THE DAY THAT HAS JUST PAST IN JOHNSON COUNTY ISOLATED THUNDERSTORMS MAY BLAST BUT ALL IN ALL AS AFTERNOON TEMPERATURES CLIMB IT LOOKS NICE FOR THE FIRST DAY OF SUMMERTIME. IN OTHER WORDS...THE UPPER LEVEL LOW WILL LIFT INTO MONTANA AND LOSE SOME ITS INFLUENCE OVER THE WEATHER. A BIT MORE MOISTURE MAY HANG AROUND FAR NORTHERN AND NORTHEASTERN WYOMING BUT ANY CONVECTION SHOULD BE ISOLATED AT BEST WITH A VAST MAJORITY OF THE AREA RAIN FREE. SATURDAY LOOKS LIKE A FAIRLY SIMILAR TODAY WITH ISOLATED CONVECTION ACROSS THE FAR NORTH AND EAST WITH SLIGHTLY DEEPER MOISTURE BRUSHING BY. TEMPERATURES WILL BE SOMEWHAT ABOVE NORMAL BUT NOT UNUSUALLY SO. AS FOR SUNDAY AND MONDAY...CONTINUITY INDICATED MAINLY ISOLATED ACTIVITY ACROSS MORE OF THE AREA WITH SOMEWHAT MORE MOISTURE SPREADING IN. THE EUROPEAN LOOKS MAINLY DRY WITH THE RIDGE AXIS OVER THE AREA BUT GIVEN UNCERTAINTY ONLY MINOR CHANGES WERE MADE. && .AVIATION.../00Z ISSUANCE/ SHOWERS AND THUNDERSTORMS WILL IMPACT EASTERN WYOMING THROUGH 04Z THIS EVENING...WEAKENING WITH LOSS OF DAYLIGHT. FOR MOST OF THE FORECAST AREA...THESE STORMS SHOULD REMAIN OVER THE MOUNTAINS. HOWEVER...KCPR WILL SEE THE POTENTIAL FOR SOME SHOWER ACTIVITY...WHICH MAY BRING BRIEF PERIODS OF MVFR CONDITIONS. CONDITIONS WILL IMPROVE THROUGH THE EVENING AND OVERNIGHT HOURS WITH WIDESPREAD VFR CONDITIONS EXPECTED AT THE TERMINALS. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL IMPACT WESTERN AND CENTRAL WYOMING AFTER 18Z TUESDAY. STORMS MAY IMPACT MORE TERMINALS ACROSS THE AREA...ESPECIALLY AFTER 20Z. MVFR CONDITIONS WITH GUSTY WIND AND SMALL HAIL MAY BE PRESENT THROUGH THE AFTERNOON. A STRONGER STORM WILL BE POSSIBLE AROUND KCPR...POTENTIALLY BRINGING VERY STRONG WIND TO THE TERMINAL. && .FIRE WEATHER... SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS PORTIONS OF EASTERN AND NORTHERN WYOMING THROUGH THE EVENING HOURS TONIGHT. ACTIVITY WILL WEAKEN WITH LOSS OF DAYLIGHT...THOUGH SOME MAY LINGER OVER THE CENTRAL MOUNTAINS. ANOTHER WARM AND DRY DAY IS EXPECTED ACROSS SOUTHERN WYOMING ON TUESDAY...WITH HUMIDITY DECREASING INTO THE SINGLE DIGITS. A SLIGHT INCREASE IN WIND IS ANTICIPATED DURING THE AFTERNOON...BUT SHOULD NOT BE SIGNIFICANT. HOWEVER...STRONGER THUNDERSTORMS MAY RETURN TO NORTHEASTERN WYOMING DURING THE AFTERNOON. THE STRONGEST STORMS MAY HAVE THE POTENTIAL FOR STRONG ERRATIC WIND AND LARGER HAIL. THE PROMINENT AREAS FOR THIS DEVELOPMENT ARE JOHNSON AND NATRONA COUNTIES...WITH SOME POTENTIAL OVER THE BIGHORN BASIN. && .RIW WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BRANHAM LONG TERM...HATTINGS AVIATION...BRANHAM FIRE WEATHER...BRANHAM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
347 AM MDT WED JUN 19 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM MDT WED JUN 19 2013 ...ISOLATED SEVERE THREAT FAR EASTERN PLAINS...FIRE WEATHER OVER MTNS/VALLEYS... CURRENTLY... AN ISOLATED STRONG TO SEVERE STORM HAS BEEN TRACKING OVER THE FAR SOUTHEAST PLAINS EARLY THIS MORNING. STORM HAS TRACKED IN REMOTE AREAS SO NO REPORTS...BUT ALGORITHMS HAVE BEEN INDICATING 2" HAIL WITH IT AT TIMES...AND MODEST ROTATION HAS BEEN OCCURRING ON AND OFF WITH THE CELL. OVER THE REST OF THE PLAINS...LLVL MSTR HAS REMAINED IN PLACE WITH SFC SE WINDS OVER THE REGION. SKIES HAVE CLOUDED UP OVER A GOOD PART OF THE PLAINS WITH CIGS IN THE MVFR/IFR CATEGORY. OVER THE INTERIOR MTNS...THE DRY AIR IS NOTED AS DWPTS ARE IN THE SINGLE DIGITS ACROSS THE SAN JUANS. TODAY... SIMULATIONS SHOW THE DRYLINE WILL REMAIN ON THE COLORADO SIDE OF THE CO/KS BORDER THIS AFTERNOON. ALTHOUGH TEMPS WILL BE WARMING ALOFT...CONVG ALONG THE BOUNDARY MAY ALLOW FOR ONE OR TWO STORMS TO FORM. LATEST HRRR WAS HINTING AT THIS. SPC ALSO HAS FAR E PLAINS IN SLIGHT RISK. CAPE IS FCST TO BE SIGNIFICANT...3000 J/KG...AND SHEAR WILL BE IN THE 35-45 KT RANGE...SO IF ANY STORM GOES UP IT WILL ROTATE AND IT WILL HAVE THE POTENTIAL TO PRODUCE SOME BIG HAIL. LCLS WILL BE HIGH SO TORNADO THREAT IS VERY LOW. OVER THE REST OF THE REGION...METEOROLOGICAL CONDITIONS WILL BE FAVORABLE FOR EXTREME FIRE BEHAVIOR GIVEN THE LOW DWPTS AND GUSTY SW WINDS. QUITE A FEW AREAS ON THE PLAINS HAVE RECEIVED SOME BENEFICIAL RAIN SO THE THREAT IS LESS ALONG THE I-25 CORRIDOR...HOWEVER IT WILL DRY OUT QUICKLY TODAY AND ANY AREAS WHICH HAVE NOT RECEIVED ANY SIGNIF RAIN WILL HAVE THE POTENTIAL FOR EXTREME FIRE BEHAVIOR. IT WILL BE MUCH WARMER TODAY THAN THE YESTERDAY...WITH HIGHS APPROACHING 100 OVER THE LOWER ARK RVR VALLEY. EXPECT 70S MTNS WITH 80S IN THE VALLEYS. TEMPS AROUND 90F WILL OCCUR IN MOST OF EL PASO COUNTY. TONIGHT... EXCEPT FOR THE SLIGHT CHANCE OF A SUPERCELL OVER THE FAR E PLAINS EARLY THIS EVENING...IT WILL BE DRY. RH RECOVERY WILL BE VERY POOR OVER THE MTNS...VALLEYS AND I-25 CORRIDOR REGION. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 323 AM MDT WED JUN 19 2013 ...HIGH FIRE DANGER... MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED WITH A SLOW MOVING SYSTEM OUT OF THE PACIFIC NORTHWEST INTO THE NORTHERN PLAINS AND PERSISTENT SOUTHWESTERLY FLOW ACROSS THE ROCKIES. THIS WILL PUT THE REGION UNDER FAVORABLE CONDITIONS FOR HIGH FIRE DANGER. THURSDAY THROUGH SATURDAY...STRONG DRY PERSISTENT SOUTHWESTERLY FLOW WILL ENCOMPASS SOUTHERN COLORADO THROUGH THIS PERIOD. THIS WILL SET THE STAGE FOR EXTREME FIRE DANGER FOR MUCH OF SOUTHERN COLORADO...ESPECIALLY WEST OF I-25. ALREADY HAVE A FIRE WEATHER WATCH OUT FOR THURSDAY AFTERNOON...AND WILL LIKELY NEED TO RAISE ONE FOR FRIDAY AFTERNOON AS WELL IN THE NEAR FUTURE. WIDESPREAD WINDS OF 20 TO 30 MPH ARE EXPECTED EACH AFTERNOON THROUGH SATURDAY WHILE HUMIDITY VALUES WILL DROP WELL BELOW 10 PERCENT. IN ADDITION THE AFTERNOON MIXING WILL ALLOW TEMPERATURES TO CLIMB INTO THE UPPER 90S TO LOWER 100S ACROSS THE PLAINS. THERE ARE SOME FIRE WEATHER CONCERNS EAST OF I-25 AS WELL...CONDITIONS WILL BE FAVORABLE HOWEVER FUEL STATUS AND RECENT HEAVY RAINS PRECLUDE ANY FIRE WEATHER HIGHLIGHTS AT THIS TIME. FINE FUELS WILL NEED TO BE WATCHED AND MAY CURE QUICKLY WITH PERSISTENT DRY AND WINDY CONDITIONS LEADING TO ENHANCED FIRE DANGER. THE ONLY AREA THAT MAY SEE ANY PRECIPITATION DURING THE EXTENDED PERIOD WILL BE THE FAR SOUTHEAST PLAINS ON FRIDAY AFTERNOON AND EVENING WHERE AN ISOLATED THUNDERSTORM WILL BE POSSIBLE...BUT CONFIDENCE IS LOW IN OCCURRENCE AT THIS TIME. SUNDAY THROUGH TUESDAY...THE UPPER PATTERN BEGINS TO SHIFT ON SUNDAY WITH THE UPPER SYSTEM OVER THE NORTHERN PLAINS EJECTING INTO THE GREAT LAKES AND HIGH PRESSURE BUILDING NORTHWARD OUT OF THE DESERT SOUTHWEST. TEMPERATURES MAY BE SLIGHTLY COOLER ON SUNDAY BEHIND A WEAK COLD FRONT...BUT WE SHOULD STILL MANAGE MID TO UPPER 90S ACROSS THE PLAINS BEFORE WARMING BACK UP FOR MONDAY AND TUESDAY. HUMIDITY VALUES WILL REMAIN LOW THROUGH THIS PERIOD...BUT WITH HIGH PRESSURE BUILDING OVERHEAD...WINDS SHOULD WEAKEN AND HELP REDUCE THE HIGH FIRE DANGER. THE EXCEPTION MAY BE THE CONTINENTAL DIVIDE AREA SUNDAY AND MONDAY WHERE SOUTHWESTERLY FLOW WILL REMAIN A BIT STRONGER BEFORE WEAKENING ON TUESDAY. THIS WILL NEED TO BE MONITORED. CURRENT MODEL PROJECTIONS INDICATING THAT WE WILL REMAIN DRY WITH NO CHANCES FOR PRECIPITATION EARLY TO MIDDLE NEXT WEEK. MOZLEY && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 323 AM MDT WED JUN 19 2013 MORNING LOW CIGS WILL AFFECT KCOS AND KPUB THROUGH ABOUT 14Z WITH VFR THROUGH THE REMAINDER OF THE VALID TAF PERIOD. KALS WILL BE VFR NEXT 24H. GUSTY SOUTHWEST WINDS WILL OCCUR AT ALL TAF SITES THIS AFTERNOON...WITH WIND GUSTS IN THE 20 TO 30 KT RANGE. && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 11 AM THIS MORNING TO 8 PM MDT THIS EVENING FOR COZ220>230. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR COZ220>230. && $$ SHORT TERM...HODANISH LONG TERM...MOZLEY AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
244 AM CDT WED JUN 19 2013 .DISCUSSION... 849 PM CDT VERY LITTLE CHANGE MADE TO THE GOING FORECAST FOR THE REST OF TONIGHT. THE HIGH PRESSURE RIDGE CONTINUES TO BUILD DOWN THE LAKE RESULTING IN A PRESSURE GRADIENT ACROSS NE IL AND NW IN. THIS COUPLED WITH THE LONG NNE FETCH OF THE WINDS OVER THE LAKE HAS CONTINUED TO ALLOW FOR 20+ MPH GUSTS EARLY THIS EVE. THESE LOOK SLOW TO SUBSIDE PER OBSERVATIONAL TRENDS AND THE RAP BUFKIT SOUNDINGS. SO THESE WILL ADD A LITTLE NIP IN THE AIR...BY JUNE STANDARDS...ACROSS CHICAGO WITH TEMPS FALLING SLOWLY THROUGH THE MID-UPPER 50S. THE COOLEST TEMPS TONIGHT STILL LOOK TO BE ALONG THE STATE LINE WHERE CONDITIONS SHOULD DECOUPLE. UPPER 40S SHOULD BE REALIZED THERE. MTF //PREV DISCUSSION... 239 PM CDT STRATUS LAYER THAT WAS ANCHORED OVER FAR NORTHEAST IL/NORTHWEST IN THIS MORNING HAS ERODED WITH THE WARM AIR HEATING THE SFC. VISIBLE IMAGERY INDICATES A FEW AREAS OF CUMULUS CLOUDS THAT HAVE DEVELOPED THIS AFTERNOON ACROSS NORTHERN IL. IN ADDITION SOME BUILDING CUMULUS CLOUDS WERE NOTED ALONG A PONTIAC TO KANKAKEE LINE...IN AN AREA OF A STRONGER THERMAL DIFFERENTIAL. HOWEVER THE LIFT MECHANISM IN THIS AREA IS MINIMAL...AND SO A FEW ISOLATED SHOWERS/THUNDERSTORMS MAY DEVELOP BUT QUICKLY DISSIPATE. ALL PRECIPITATION OVER THE CWFA WILL BE DIURNALLY DRIVEN...THUS BY SUNSET OR IMMEDIATELY AFTER SUNSET PRECIP WILL COME TO AN END. FURTHER SOUTH STRONGER INSTABILITY WAS POSITIONED ACROSS CENTRAL IL STRETCHING WEST THROUGH NORTHERN MISSOURI. MID-LVL WAVE CONTINUES TO PIVOT EAST ACROSS FAR NORTHWEST IL THIS AFTERNOON...AND WILL MAINTAIN THE NORTHEAST FLOW ACROSS MUCH OF THE CWFA. AS A RESULT COOL TEMPS WILL PERSIST THIS EVENING...WITH MINIMAL CLOUD COVER FROM THE DIFFLUENT FLOW ALOFT. SKIES WILL BECOME MOSTLY CLEAR TONIGHT...WITH THE LLVL FLOW WEAKENING. THIS SHOULD PROVIDE DECENT RADIATIONAL COOLING WITH TEMPS OVERNIGHT EXPECTED TO BE IN THE MID 50S SOUTH OF I-80. FURTHER NORTH TEMPS WILL BE MUCH COOLER TO ARND 50...POSSIBLY THE UPR 40S FOR AREAS ALONG AND NORTH OF A ROCKFORD...AURORA...WAUKEGAN LINE. CONFIDENCE...HIGH. WEDNESDAY THROUGH THURSDAY... 500MB TROUGH AXIS SLOWLY PIVOTS TO THE EASTERN GREAT LAKES WED...AND WILL CONTINUE TO PUSH EAST THUR. THE SFC RIDGE WILL ALSO BEGIN TO PUSH EAST...HOWEVER AN ONSHORE OR NORTHEAST TO EAST FLOW WILL PERSIST INTO WED FOR MUCH OF NORTHERN IL. THE DIFFERENCE FOR WED WILL BE THAT THE 850MB THERMAL TROUGH WILL LINGER OVERHEAD. WITH ABUNDANT SUNSHINE AND SFC HEATING...TEMPS SHUD WARM INTO THE MID/UPR 70S OR POSSIBLY THE LOW 80S FROM LASALLE TO IROQUOIS COUNTY. FOR THUR 500MB HEIGHTS WILL BEGIN TO RISE WITH FLOW BEGINNING TO TURN TO THE SOUTHEAST IN THE LLVLS. A WEAK LAKE BREEZE MAY DEVELOP AND PUSH INTO LAKE COUNTY IL...WHICH WOULD MOST LIKELY PROVIDE A COOLING TREND IN THE AFTN HOURS. 850MB TEMPS WILL STEADILY WARM FOR THUR TO ARND 14 TO 16 DEG C...WITH CONTINUED THIN CLOUD COVER. THIS WILL ALLOW TEMPS TO WARM INTO THE LOW/MID 80S. THE CAVEAT WILL BE AREAS OF LAKE COUNTY IL POST FRONTAL PASSAGE THAT WILL ALLOW TEMPS TO FALL INTO THE 60S IN THE AFTN. IT DOES APPEAR THAT ENOUGH DRY AIR WILL LINGER THRU THUR AFTN/EVE...THUS HAVE HELD ONTO A DRY FORECAST IN THIS TIMEFRAME. THIS PATTERN WILL BE CHANGING AS WE MIGRATE INTO THE EXTENDED PERIODS. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN DRY WEATHER THROUGH THUR...MEDIUM/HIGH. FRIDAY THROUGH MONDAY... MINIMAL CHANGES FROM PREVIOUS FORECAST IN REGARDS TO THE EXTENDED PERIODS. POSSIBLY THE FIRST STRETCH OF 90 DEG DAYS IS UPON US FOR SUN/MON/TUE. GUIDANCE HAS A WARM FRONTAL BOUNDARY LIFTING OVERHEAD FRI WITH SOUTHERLY FLOW USHERING IN ADDTL LLVL MOISTURE. IT DOES APPEAR A WAVE WILL ALSO PUSH OVER THE CWFA FRI...WITH POTENTIAL FOR SHOWERS/THUNDERSTORMS. TEMPS WILL BE SLIGHTLY WARM FOR FRI INTO THE UPR 80S...WITH A FEW 90 DEGREE POINTS ACROSS THE CWFA. ENSEMBLES FOR SEVERAL DAYS HAVE CONTINUED TO INDICATE THAT A 500MB RIDGE ACROSS THE CENTRAL CONUS WILL ADVECT EAST AND BECOME ANCHORED ACROSS THE EASTERN HALF OF THE CONUS BY THE WEEKEND AND POSSIBLY PERSIST THROUGH EARLY NEXT WEEK. ADDITIONALLY...GUIDANCE HAS PROGGED 850MB TEMPS TO RISE TO ARND 20-22 DEG C FOR THE WEEKEND THRU EARLY NEXT WEEK. CONSISTENCY FROM PREVIOUS RUNS SUGGESTS HIGH CONFIDENCE IN THIS WARM STRETCH ARRIVING. THEN SUN/MON/TUE APPEAR TO BE NEAR CARBON COPIES WITH TEMPS EASILY WARMING TO 90 DEGREES...POSSIBLY THE LOW 90S. CLIMATOLOGY BASED ON THE 850MB TEMPS PROGGED AND TIME OF YEAR WOULD SUGGEST TEMPS TO BE WARMER AS FORECASTED. A COUPLE LIMITING FACTORS MIGHT BE THE POTENTIAL FOR A SERIES OF WAVES BRINGING INSTABILITY AND THUNDERSTORM POTENTIAL EACH DAY OF THE EXTENDED...ALONG WITH DEW PTS PROGGED TO BE ARND 70 DEG. THIS COULD POTENTIALLY KEEP TEMPS IN CHECK IN THE MID/UPR 80S. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN PRECIP/CONVECTIVE FORECAST...MEDIUM/HIGH. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LAKE BREEZE WEDNESDAY AFTERNOON. BMD //DISCUSSION...UPDATED 06Z... HIGH PRESSURE SPANS THE GREAT LAKES REGION TONIGHT WITH LIGHT FLOW EXPECTED THROUGH THE TAF PERIOD. WINDS SHOULD SYNOPTICALLY VEER EAST THEN SOUTHEAST...BUT A LAKE BREEZE MAY INTERRUPT THIS PROCESS WEDNESDAY AFTERNOON TURNING WINDS BACK TO NORTHEAST FOR A PERIOD. WITH SUNSET...WINDS SHOULD THEN VEER AGAIN TO THE SOUTHEAST AS THE HIGH CONTINUES TO SETTLE SOUTHEAST TOWARDS THE MID ATLANTIC COAST. OUTSIDE OF THE INFLUENCE OF THE LAKE BREEZE WEDNESDAY AFTERNOON...EXPECT WINDS TO REMAIN LESS THAN 10 KT. VFR CONDITIONS ARE ALSO EXPECTED TO PREVAIL THROUGH THE PERIOD. BMD //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM CONFIDENCE IN WIND DIRECTION FORECAST...HIGH CONFIDENCE IN WIND SPEEDS. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. BMD //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... THURSDAY...VFR. FRIDAY THROUGH MONDAY...PERIODIC CHANCES FOR TSRA...OTHERWISE VFR. LENNING && .MARINE... 243 AM CDT HIGH PRESSURE IS CENTERED OVER THE CENTRAL GREAT LAKES REGION EARLY THIS MORNING AND IS FORECAST TO MOVE SOUTHEAST TOWARDS THE MID ATLANTIC COAST BY THURSDAY. MEANWHILE...WINDS AND WAVES HAVE ALREADY DIMINISHED UNDER THE INFLUDENCE OF THE HIGH...THUS WILL ALLOW REMAINING SMALL CRAFT ADVISORIES TO EXPIRE WITH THE MORNING FORECAST PACKAGE. WITH LIGHT FLOW IN PLACE TODAY...WINDS WILL BECOME OFFSHORE THIS AFTERNOON AS LAKE BREEZES DEVELOP ACROSS THE ENTIRE LAKE. AS THE HIGH SETTLES TO OUR EAST THURSDAY...AND LOW PRESSURE OVER THE PLAINS...WINDS WILL BEGIN TO TURN SOUTHERLY...AND FRESHEN UP FRIDAY AS THE LOW LIFTS INTO THE UPPER MIDWEST. SOUTHERLY FLOW WILL DOMINATE THE REMAINDER OF THE WEEKEND INTO EARLY NEXT WEEK. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 4 AM WEDNESDAY. IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 4 AM WEDNESDAY. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
100 AM CDT WED JUN 19 2013 .DISCUSSION... 849 PM CDT VERY LITTLE CHANGE MADE TO THE GOING FORECAST FOR THE REST OF TONIGHT. THE HIGH PRESSURE RIDGE CONTINUES TO BUILD DOWN THE LAKE RESULTING IN A PRESSURE GRADIENT ACROSS NE IL AND NW IN. THIS COUPLED WITH THE LONG NNE FETCH OF THE WINDS OVER THE LAKE HAS CONTINUED TO ALLOW FOR 20+ MPH GUSTS EARLY THIS EVE. THESE LOOK SLOW TO SUBSIDE PER OBSERVATIONAL TRENDS AND THE RAP BUFKIT SOUNDINGS. SO THESE WILL ADD A LITTLE NIP IN THE AIR...BY JUNE STANDARDS...ACROSS CHICAGO WITH TEMPS FALLING SLOWLY THROUGH THE MID-UPPER 50S. THE COOLEST TEMPS TONIGHT STILL LOOK TO BE ALONG THE STATE LINE WHERE CONDITIONS SHOULD DECOUPLE. UPPER 40S SHOULD BE REALIZED THERE. MTF //PREV DISCUSSION... 239 PM CDT STRATUS LAYER THAT WAS ANCHORED OVER FAR NORTHEAST IL/NORTHWEST IN THIS MORNING HAS ERODED WITH THE WARM AIR HEATING THE SFC. VISIBLE IMAGERY INDICATES A FEW AREAS OF CUMULUS CLOUDS THAT HAVE DEVELOPED THIS AFTERNOON ACROSS NORTHERN IL. IN ADDITION SOME BUILDING CUMULUS CLOUDS WERE NOTED ALONG A PONTIAC TO KANKAKEE LINE...IN AN AREA OF A STRONGER THERMAL DIFFERENTIAL. HOWEVER THE LIFT MECHANISM IN THIS AREA IS MINIMAL...AND SO A FEW ISOLATED SHOWERS/THUNDERSTORMS MAY DEVELOP BUT QUICKLY DISSIPATE. ALL PRECIPITATION OVER THE CWFA WILL BE DIURNALLY DRIVEN...THUS BY SUNSET OR IMMEDIATELY AFTER SUNSET PRECIP WILL COME TO AN END. FURTHER SOUTH STRONGER INSTABILITY WAS POSITIONED ACROSS CENTRAL IL STRETCHING WEST THROUGH NORTHERN MISSOURI. MID-LVL WAVE CONTINUES TO PIVOT EAST ACROSS FAR NORTHWEST IL THIS AFTERNOON...AND WILL MAINTAIN THE NORTHEAST FLOW ACROSS MUCH OF THE CWFA. AS A RESULT COOL TEMPS WILL PERSIST THIS EVENING...WITH MINIMAL CLOUD COVER FROM THE DIFFLUENT FLOW ALOFT. SKIES WILL BECOME MOSTLY CLEAR TONIGHT...WITH THE LLVL FLOW WEAKENING. THIS SHOULD PROVIDE DECENT RADIATIONAL COOLING WITH TEMPS OVERNIGHT EXPECTED TO BE IN THE MID 50S SOUTH OF I-80. FURTHER NORTH TEMPS WILL BE MUCH COOLER TO ARND 50...POSSIBLY THE UPR 40S FOR AREAS ALONG AND NORTH OF A ROCKFORD...AURORA...WAUKEGAN LINE. CONFIDENCE...HIGH. WEDNESDAY THROUGH THURSDAY... 500MB TROUGH AXIS SLOWLY PIVOTS TO THE EASTERN GREAT LAKES WED...AND WILL CONTINUE TO PUSH EAST THUR. THE SFC RIDGE WILL ALSO BEGIN TO PUSH EAST...HOWEVER AN ONSHORE OR NORTHEAST TO EAST FLOW WILL PERSIST INTO WED FOR MUCH OF NORTHERN IL. THE DIFFERENCE FOR WED WILL BE THAT THE 850MB THERMAL TROUGH WILL LINGER OVERHEAD. WITH ABUNDANT SUNSHINE AND SFC HEATING...TEMPS SHUD WARM INTO THE MID/UPR 70S OR POSSIBLY THE LOW 80S FROM LASALLE TO IROQUOIS COUNTY. FOR THUR 500MB HEIGHTS WILL BEGIN TO RISE WITH FLOW BEGINNING TO TURN TO THE SOUTHEAST IN THE LLVLS. A WEAK LAKE BREEZE MAY DEVELOP AND PUSH INTO LAKE COUNTY IL...WHICH WOULD MOST LIKELY PROVIDE A COOLING TREND IN THE AFTN HOURS. 850MB TEMPS WILL STEADILY WARM FOR THUR TO ARND 14 TO 16 DEG C...WITH CONTINUED THIN CLOUD COVER. THIS WILL ALLOW TEMPS TO WARM INTO THE LOW/MID 80S. THE CAVEAT WILL BE AREAS OF LAKE COUNTY IL POST FRONTAL PASSAGE THAT WILL ALLOW TEMPS TO FALL INTO THE 60S IN THE AFTN. IT DOES APPEAR THAT ENOUGH DRY AIR WILL LINGER THRU THUR AFTN/EVE...THUS HAVE HELD ONTO A DRY FORECAST IN THIS TIMEFRAME. THIS PATTERN WILL BE CHANGING AS WE MIGRATE INTO THE EXTENDED PERIODS. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN DRY WEATHER THROUGH THUR...MEDIUM/HIGH. FRIDAY THROUGH MONDAY... MINIMAL CHANGES FROM PREVIOUS FORECAST IN REGARDS TO THE EXTENDED PERIODS. POSSIBLY THE FIRST STRETCH OF 90 DEG DAYS IS UPON US FOR SUN/MON/TUE. GUIDANCE HAS A WARM FRONTAL BOUNDARY LIFTING OVERHEAD FRI WITH SOUTHERLY FLOW USHERING IN ADDTL LLVL MOISTURE. IT DOES APPEAR A WAVE WILL ALSO PUSH OVER THE CWFA FRI...WITH POTENTIAL FOR SHOWERS/THUNDERSTORMS. TEMPS WILL BE SLIGHTLY WARM FOR FRI INTO THE UPR 80S...WITH A FEW 90 DEGREE POINTS ACROSS THE CWFA. ENSEMBLES FOR SEVERAL DAYS HAVE CONTINUED TO INDICATE THAT A 500MB RIDGE ACROSS THE CENTRAL CONUS WILL ADVECT EAST AND BECOME ANCHORED ACROSS THE EASTERN HALF OF THE CONUS BY THE WEEKEND AND POSSIBLY PERSIST THROUGH EARLY NEXT WEEK. ADDITIONALLY...GUIDANCE HAS PROGGED 850MB TEMPS TO RISE TO ARND 20-22 DEG C FOR THE WEEKEND THRU EARLY NEXT WEEK. CONSISTENCY FROM PREVIOUS RUNS SUGGESTS HIGH CONFIDENCE IN THIS WARM STRETCH ARRIVING. THEN SUN/MON/TUE APPEAR TO BE NEAR CARBON COPIES WITH TEMPS EASILY WARMING TO 90 DEGREES...POSSIBLY THE LOW 90S. CLIMATOLOGY BASED ON THE 850MB TEMPS PROGGED AND TIME OF YEAR WOULD SUGGEST TEMPS TO BE WARMER AS FORECASTED. A COUPLE LIMITING FACTORS MIGHT BE THE POTENTIAL FOR A SERIES OF WAVES BRINGING INSTABILITY AND THUNDERSTORM POTENTIAL EACH DAY OF THE EXTENDED...ALONG WITH DEW PTS PROGGED TO BE ARND 70 DEG. THIS COULD POTENTIALLY KEEP TEMPS IN CHECK IN THE MID/UPR 80S. CONFIDENCE IN TEMPERATURE FORECAST...HIGH. CONFIDENCE IN PRECIP/CONVECTIVE FORECAST...MEDIUM/HIGH. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LAKE BREEZE WEDNESDAY AFTERNOON. BMD //DISCUSSION...UPDATED 06Z... HIGH PRESSURE SPANS THE GREAT LAKES REGION TONIGHT WITH LIGHT FLOW EXPECTED THROUGH THE TAF PERIOD. WINDS SHOULD SYNOPTICALLY VEER EAST THEN SOUTHEAST...BUT A LAKE BREEZE MAY INTERRUPT THIS PROCESS WEDNESDAY AFTERNOON TURNING WINDS BACK TO NORTHEAST FOR A PERIOD. WITH SUNSET...WINDS SHOULD THEN VEER AGAIN TO THE SOUTHEAST AS THE HIGH CONTINUES TO SETTLE SOUTHEAST TOWARDS THE MID ATLANTIC COAST. OUTSIDE OF THE INFLUENCE OF THE LAKE BREEZE WEDNESDAY AFTERNOON...EXPECT WINDS TO REMAIN LESS THAN 10 KT. VFR CONDITIONS ARE ALSO EXPECTED TO PREVAIL THROUGH THE PERIOD. BMD //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM CONFIDENCE IN WIND DIRECTION FORECAST...HIGH CONFIDENCE IN WIND SPEEDS. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. BMD //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... THURSDAY...VFR. FRIDAY THROUGH MONDAY...PERIODIC CHANCES FOR TSRA...OTHERWISE VFR. LENNING && .MARINE... 137 PM CDT A SURFACE RIDGE OF HIGH PRESSURE ACROSS THE UPPER GREAT LAKES REGION...WILL SHIFT EASTWARD TOWARDS NEW ENGLAND BY WEDNESDAY EVENING. MEANWHILE...LOW PRESSURE IS EXPECTED TO TAKE SHAPE ACROSS THE PLAINS STATES. THIS PRESSURE PATTERN WILL REMAIN IN PLACE FOR A FEW DAYS INTO THE WEEKEND. OVERALL...THIS WILL RESULT IN A PROLONGED PERIOD OF SOUTHERLY WINDS ACROSS THE LAKE. WIND MAGNITUDES GENERALLY LOOK TO BE IN THE 10 TO 20 KT RANGE...WITH A FEW PERIODS OF 15 TO 25 KT SOUTHERLY WINDS...ESPECIALLY LATER IN THE PERIOD. THERE WILL ALSO BE INCREASING CHANCES FOR A FEW PERIODS OF THUNDERSTORM ACTIVITY FRIDAY AND INTO THE WEEKEND OVER THE LAKE. A FAIRLY ACTIVE WEATHER PATTERN LOOKS TO SETUP UP ACROSS THE GREAT THE NORTHERN CONUS AND GREAT LAKES REGION. IN THE SHORTER TERM...I HAVE EXTENDED THE SMALL CRAFT ADVISORY INTO THIS EVENING FOR THE ILLINOIS SHORES AND MAINTAINED THE ADVISORY THROUGH LATE TONIGHT FOR THE INDIANA SHORES. LOCAL BUOY OBS INDICATE WAVES AROUND 4 FT...AND WITH THE ONSHORE FLOW CONTINUING TO BE IN THE 15 TO 20 KT RANGE AHEAD OF THE SURFACE HIGH...I DO NOT SEE ANY IMPROVEMENT IN THE WAVE CONDITIONS FOR SEVERAL MORE HOURS. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 4 AM WEDNESDAY. IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 4 AM WEDNESDAY. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 AM WEDNESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS DES MOINES IA
346 AM CDT WED JUN 19 2013 .SHORT TERM.../TODAY/... ISSUED AT 339 AM CDT WED JUN 19 2013 HIGH PRESSURE RIDGE MOVING OFF TO THE EAST NOW WITH WAA BEGINNING TO MOVE INTO WRN IA. SAT PIX SHOW AN INCREASE IN CLODS FROM DECAYING BLOWOFF CLOUDS. DEEPER MOISTURE CONVERGENCE MOVING INTO SWRN IA WILL BRING AT LEAST ISOLATED TSRA THIS MORNING AS WAA ARC LIFTS NORTHEAST ACROSS THE CWA. KEPT THE PRECIP TO THE WEST HALF HOWEVER. COMBINATION OF NAMDNG5 AND HRRR GIVES A REASONABLE PRESENTATION OF EXPECTED OUTCOME. TEMPS TODAY VERY DEPENDENT ON CLOUD COVER. FEEL THERE WILL BE ENOUGH BREAKS TO GET HIGHS A LITTLE ABOVE MOS GUID AND WARMER THAN YESTERDAY IN MOST LOCATIONS. .LONG TERM.../TONIGHT THROUGH TUESDAY/... ISSUED AT 339 AM CDT WED JUN 19 2013 COMPLICATED FORECAST FOR EXTENDED...WITH MANY PERIODS OF POPS...AND SOMEWHAT LOW CONFIDENCE IN TIMING...WITH BREAKS IN PRECIP CHANCES FROM TIME TO TIME THROUGH THE REMAINDER OF THE WEEK. LARGE UPPER LEVEL LOW WILL BE DRIVER FOR PRECIPITATION CHANCES TROUGH MUCH OF THE PERIOD. LOW WILL REMAIN PRIMARILY OVER PAC NW...AND IS BEGINNING TO SLOWLY PUSH INLAND ATTM. MODELS HAVE SIGNIFICANT DISCREPANCIES OVER PLACEMENT OF LOW...BUT SHOULD COME INTO BETTER AGREEMENT AS LOW PUSHES INLAND. RIDGE REMAINS OVER IOWA THROUGH MUCH OF PERIOD...WITH SHORTWAVES PUSHING THROUGH SPARKING CONVECTION CHANCES. MODELS HAVE SIGNIFICANTLY SLOWED DOWN SHORT WAVES PROPAGATION EASTWARD...WITH FOCUS FOR DEVELOPMENT IN CENTRAL NE PUSHING INTO IOWA LATE OVERNIGHT. HAVE THEREFORE SLOWED POPS FOR OVERNIGHT...THOUGH COULD SEE SOME DEVELOPMENT AHEAD OF MAIN PRECIP BAND WITH THETA-E ADVECTION. SYSTEM IS SLOW MOVING...WITH PRECIP THROUGH THURSDAY. STRONG SHORTWAVE SET TO TRACK ACROSS NORTHERN PLAINS LATE THURSDAY. THIS WILL LIKELY BE THE FOCUS FOR SEVERE WEATHER ACROSS THE DAKOTAS...AND MAY FORM INTO MCS PUSHING ACROSS IOWA...WITH NORTHERN IOWA MOST LIKELY LOCATION OVERNIGHT THURSDAY. SEVERE WEATHER WILL BE POSSIBLE WITH THIS SYSTEM. SHORTWAVE EXPECTED TO TRACK ACROSS SOUTHERN SD/MN AND HEAVIEST PRECIP MAY STAY NORTH. NUMEROUS SHORTWAVES CONTINUE TO TRACK EAST AS UPPER LEVEL LOW REMAINS ACROSS NORTHWESTERN US. AS LOW PUSHES EASTWARD...TRACKS OF WAVES WILL LIKELY GO NORTH OF CWA...BUT MAY SEE DEVELOPMENT FURTHER SOUTH...AND HAVE KEPT POPS ACROSS THE NORTH. SOMEWHAT STRONGER WAVE PUSHES THROUGH FLOW FOR THE WEEKEND...THOUGH UPPER LEVEL LOW WILL PUSH EASTWARD AND SURFACE LOW IN WESTERN PLAINS WILL ALSO LIFT NE AT THIS TIME...AND TIMING AND LOCATION FOR PRECIPITATION CHANCES OVER THE WEEKEND IS VERY MUDDLED. AS UPPER LEVEL LOW PUSHES EAST FRONT WILL DROP ACROSS IOWA WITH PROLONGED PRECIPITATION CHANCE FOR LATE IN THE PERIOD. TEMPERATURES WILL WARM SIGNIFICANTLY UNDER THE RIDGE...WITH SURFACE SOUTHERLY FLOW. HAVE BUMPED TEMPERATURES UP WITH WAA FOR EARLY IN THE PERIOD...THOUGH MIXING MAY BE SOMEWHAT LIMITED. OVERALL...TEMPERATURES WILL WARM WITH SUMMER LIKE READINGS. && .AVIATION...19/06Z ISSUED AT 1209 AM CDT WED JUN 19 2013 VFR/MOSTLY CLEAR CONDITIONS WILL CONTINUE INTO EARLY WED MORNING. THE ONLY CONCERN IS WHETHER MVFR FOG COULD DEVELOP TOWARD DAYBREAK. TEMPS AND DEWPOINTS ARE GENERALLY A BIT LOWER/HIGHER RESPECTIVELY FROM THIS TIME YESTERDAY SO THERE IS THAT POTENTIAL WITH LIGHT E/SE WIND. HAVE ADDED MENTION IN CLIMATOLOGICALLY FAVORED LOCATIONS WHICH ARE ALSO SUPPORTED BY MOS GUIDANCE...WHICH ENDS UP TO BE EVERYWHERE OUTSIDE OF KDSM. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...MS LONG TERM...AWB AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
402 AM MDT WED JUN 19 2013 .SHORT TERM...(TODAY THROUGH FRIDAY NIGHT) ISSUED AT 402 AM MDT WED JUN 19 2013 MAIN FORECAST PROBLEM THUNDERSTORM COVERAGE/CHANCES THROUGH PERIOD WITH HOW HOT DOES IT GET THURSDAY AND FRIDAY. SATELLITE CONTINUING TO SHOW AN AMPLIFIED/BLOCKY/COMPLICATED UPPER FLOW FROM THE EASTERN PACIFIC INTO THE CENTRAL PORTION OF THE COUNTRY. UPPER LOW HAS MOVED CLOSER TO THE PACIFIC NORTHWEST WITH WEST TO SOUTHWEST FL0W ALOFT SPREADING ACROSS OUR AREA. COLD FRONT REMAINS WELL TO OUR SOUTH AND IS DRAPED UP AGAINST THE COLORADO FRONT RANGE. LARGE COMPLEX OF THUNDERSTORMS HAS PRODUCED A SIGNIFICANT COLD POOL AND HAS SENT UP MESOSCALE/CONVERGENT BOUNDARIES ACROSS DIFFERENT PORTIONS OF THE REGION. MODELS INITIALIZED FINE AT JET LEVEL. THE NAM/ECMWF LOOKED TO HAVE INITIALIZED THE WORST ON THE MID LEVELS WITH THE UKMET/CANADIAN/GFS/SREF DOING ABOUT THE SAME. NAM WAS A LITTLE WARM AT 700 MB WITH THE GFS AND UKMET BETTER. SREF AND GFS WERE DOING LITTLE BETTER THAN THE NAM AND CANADIAN ON THE LOW LEVEL THERMAL FIELD. TODAY/TONIGHT...DUE TO THE OVERNIGHT THUNDERSTORM COMPLEX THAT WENT THROUGH...MESOSCALE BOUNDARIES/CONVERGENCE DO ABOUND. SATELLITE AND UPPER AIR ANALYSIS SHOWING A COUPLE OF WEAK SHORTWAVES TO OUR WEST PLUS A WARMER AND DRIER MID LEVEL AIR MASS/EML MOVING IN FROM THE WEST. NEAR 12Z THE LEFT FRONT QUADRANT OF SOUTHERN JET WILL BE AFFECTING THE SOUTHWEST PORTION OF THE AREA. IT STAYS NEAR THE SOUTHERN PORTION OF THE AREA THROUGH AS SLOWLY PROGRESSES SOUTH AWAY FROM THE AREA. VERY UNCERTAIN PRECIPITATION FORECAST FOR THE DAY...ESPECIALLY THIS MORNING...WITH MESOSCALE FEATURES BEING A BIG INFLUENCE. CONVECTIVE CIRCULATION IS LOCATED OVER THE EASTERN PORTION OF THE AREA. ONE OF THOSE OUTFLOW BOUNDARIES LIES ACROSS THE NORTHEAST PORTION. ALL MODELS ESPECIALLY THE RAP REDEVELOPS A SIGNIFICANT PRECIPITATION AREA OVER THE NORTHEAST TO EAST PORTION OF THE AREA THIS MORNING. CONSIDERING THAT THE RAP HAS BEEN CONSISTENT FOR A COUPLE OF RUNS... MATCHES UP WITH WHERE THE BOUNDARY IS RIGHT NOW AND THAT THUNDERSTORMS HAVE REDEVELOPED ALREADY IN THE SAME GENERAL AREA... WILL RAISE POPS TO A HIGH CHANCE THIS MORNING AND CONTINUE TO MONITOR. THAT CIRCULATION AND PRECIPITATION LOOK TO EXIT THE AREA AROUND THE MIDDLE OF THE DAY. THE AIR MASS LOOKS TO RELOAD WITH EMPHASIS SHIFTING BACK TO THE WEST. SURFACE TROUGH STILL REMAINS TO THE WEST OF THE AREA. WHAT LOOKS TO BE A DRYLINE SETS UP OVER THE FAR WEST WITH THE INSTABILITY AXIS SETTING NEAR THE COLORADO AND KANSAS BORDER. THE FAR WESTERN MAY BE CAPPED THIS AFTERNOON. SHORTWAVE TROUGH MOVES IN FROM THE WEST AND EXPECT THUNDERSTORMS TO DEVELOP NEAR OR JUST TO THE EAST OF THE COLORADO BORDER. THESE STORMS SHOULD PROGRESS TO THE EAST THROUGH THE NIGHT AS THE SHORTWAVE MOVES TOWARD THE EAST AND THE LOW LEVEL JET DEVELOPS IN THE EASTERN THIRD. DO NOT HAVE A GOOD FEEL WITH THE HIGH TEMPERATURES. IT IS POSSIBLE WITH THE WET GROUND AND ONGOING CLOUD COVER AND PRECIPITATION COULD CAUSE TEMPERATURES TO BE COOLER...ESPECIALLY IN THE EAST. THURSDAY/THURSDAY NIGHT...INTERESTING FORECAST FOR THIS DAY. 700 MB TEMPERATURES REMAIN RATHER HIGH THROUGH THE DAY...WITH THE LOWEST AND CAP BREAKABLE TEMPERATURES IN THE NORTHERN AND EASTERN PORTIONS OF THE AREA. BY LATE AFTERNOON...EITHER A WEAK COOL FRONT OR SURFACE TROUGH SAGS INTO THE NORTHERN PORTION OF THE AREA WITH WHAT LOOKS TO BE A DRYLINE JUST TO THE WEST OF THE SOUTHEAST CORNER. AT THE SAME TIME A SHORTWAVE TROUGH APPROACHES FROM THE SOUTHWEST. ALL THESE FEATURES PROGRESS NORTH AND EAST THROUGH THE EVENING. BY LATE IN THE AFTERNOON A WEAK LEFT FRONT QUADRANT LOOKS TO BE JUST SOUTH OF THE FORECAST AREA. THIS LIFT MOVES SLOWLY NORTH THROUGH THE EVENING AND WILL BE AFFECT THE SOUTHEAST QUARTER BY LATE IN THE NIGHT. MODELS ARE GENERATING SOME LIGHT QPF EVEN WITH WHAT LOOKS TO BE A DEEP DRY LAYER AND HIGH BASES. BELIEVE THERE IS ENOUGH HERE TO INCLUDE A LOW SLIGHT CHANCE. HOWEVER...COULD SEE THINGS TOTALLY CAPPED OR BE ABLE TO BREAK LOOSE. ALONG AND NORTH OF THE BOUNDARY THE TEMPERATURES WILL BE SLIGHTLY COOLER...IN THE 90S. SOUTH THE BOUNDARY IT WILL BE NEAR 100 DEGREES. MODELS DO DISAGREE WITH HOW FAR SOUTH TO TAKE THE BOUNDARY. CONSIDERING THE FLOW ALOFT AND THE AIR MASS LIKE THE BOUNDARY BEING FURTHER NORTH. FRIDAY/FRIDAY NIGHT...THE CANADIAN AND ECMWF KEEP A WEAK LEFT FRONT QUADRANT OF THE JET NEAR/OVER THE EASTERN AND CENTRAL PORTION OF THE AREA THROUGH THE DAY. VERY SIMILAR SETUP TO THE DAY BEFORE EXCEPT MOST OF THE WEST AND CENTRAL PORTIONS DO LOOK CAPPED DESPITE THE SURFACE TROUGH AND DRYLINE NEAR THE SAME PLACE. THE EASTERN THIRD HAS THE LOWER 700 MB TEMPERATURES WITH THE INSTABILITY AXIS AND BEST MID LEVEL MOISTURE IN THE SAME AREA. AT THE SAME TIME A SHORTWAVE TROUGH IS COMING ACROSS. LIKED WHAT THE PREVIOUS SHIFT HAD IN THERE FOR A SLIGHT CHANCE AND ONLY MADE A SLIGHT ADJUSTMENT TO THE AREA FOR THE AFTERNOON AND EVENING HOURS. ONCE AGAIN HIGH TEMPERATURES WILL BE DETERMINED BY WHERE THE BOUNDARY SETS UP. MODEL DATA SAYS THE BOUNDARY WILL BE A LITTLE FURTHER NORTH AND SO WILL THE HOT TEMPERATURES AND TRENDED THE MAXES IN THAT DIRECTION. .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 230 AM MDT TUE JUN 19 2013 STRONG SOUTHWEST FLOW ALOFT AT 500 MB WILL PERSIST THROUGHOUT THE DAY SATURDAY AS MERIDIONAL FLOW PATTERN EXISTS OVER THE CENTRAL PLAINS. INSTABILITY WILL BE PRESENT IN THE FLOW AS EMBEDDED SHORTWAVE TROUGHS ENTER INTO OUR FORECAST AREA. AN UPPER LEVEL LOW WILL PROGRESS WESTWARD OVER THE NORTHERN HIGH PLAINS AS BLOCKING RIDGE OVER THE SOUTHERN PLAINS STRENGTHENS SATURDAY EVENING INTO SUNDAY. STRONGEST UPPER LEVEL JET WILL STAY IN THE NORTHERN PLAINS ALONG WITH STRONGEST POSITIVE VORTICITY VALUES...HOWEVER SOME POCKETS OF POSITIVE VORTICITY WILL ENTER THE TRI STATE AREA FOR SUNDAY AFTERNOON AND EVENING. THE TROUGH BECOMES NEGATIVELY TILTED AS FLOW PATTERN RETURNS TO ZONAL FLOW FOR SUNDAY EVENING AND MONDAY. THE RIDGE TO THE SOUTH WILL CONTINUE TO STRENGTHEN AND MOVE INTO THE CENTRAL PLAINS FOR TUESDAY...AND JET STREAM WILL STAY WELL TO THE NORTH OF THE AREA FOR THE REST OF NEXT WEEK. 850 MB JET SPEEDS ARE VERY STRONG DUE TO NOCTURNAL EFFECT FOR OVERNIGHT SATURDAY AND SUNDAY TOWARD WEST CENTRAL KANSAS...WHICH COULD PROVIDE SOME UNSTABLE WEATHER WITH UPPER LEVEL SHORTWAVE FORCING. ONCE RIDGE BUILDS INTO THE REGION...THE JET SPEEDS WILL DECREASE AND BECOME CALM FOR THE REST OF NEXT WEEK. AT THE SURFACE...STRONG WARM AIR ADVECTION WILL BE PRESENT ACROSS THE AREA WITH TEMPERATURES REACHING THE MID TO UPPER 90S FOR THE WEEKEND. 850 MB TEMPERATURES ARE ALSO WARM...WITH VALUES IN THE MID 80S SATURDAY AND SUNDAY. THETA E VALUES ARE MARGINAL AT 850 AND AT THE SURFACE...WITH HIGHER VALUES TOWARD CENTRAL KANSAS. DEW POINTS WILL BE IN THE MID 50S ACROSS THE REGION...WITH A 30 DEGREE DRY LINE GRADIENT PRESENT IN THE WESTERN CWA. ALTHOUGH BEST SURFACE BOUNDARY EXISTS FOR THE AREA SATURDAY AND SUNDAY...INSTABILITY PARAMETERS ARE MARGINAL AT BEST. THERE ARE SOME CHANCES FOR THUNDERSTORM DEVELOPMENT SATURDAY AND SUNDAY AFTERNOON...BUT THE BEST CHANCE IS TO THE EAST TOWARDS MORE UNSTABLE ENVIRONMENT IN CENTRAL KANSAS. STRONG SOUTH/SOUTHWEST FLOW WILL RETURN TO THE REGION FOR MONDAY AFTERNOON AND FOR THE REST OF THE WEEK...BRINGING WARM AIR AND DRY CONDITIONS TO MUCH OF THE AREA. AFTERNOON AND EVENING THUNDERSTORMS WILL DEVELOP ACROSS MUCH OF THE AREA FOR THE WEEKEND AS WARM FRONT INCREASES TEMPERATURES. MORE STABLE UPPER LEVEL AIR WILL MOVE INTO THE HIGH PLAINS REGION FOR NEXT WEEK...PROVIDING DRY CONDITIONS AND TEMPERATURES THAT MAY REACH NEAR 100. && .AVIATION....(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1131 PM MDT TUE JUN 18 2013 MVFR TO VFR CONDITIONS FORECAST FOR THE 6Z TAFS. RATHER COMPLICATED WEATHER PATTERN OVERNIGHT DUE TO VARIOUS OUTFLOW BOUNDARIES ALONG WITH LINGERING ELEVATED INSTABILITY. MESOSCALE STORM COMPLEX SHOULD BE EAST OF KGLD BY THE START OF THE TAFS...WITH ISOLATED TO SCATTERED STORM COVERAGE BEHIND THE COMPLEX INTO THE OVERNIGHT HOURS. THE STORM ACTIVITY SHOULD REMAIN SOUTH AND EAST OF KMCK...ALTHOUGH A FEW STORMS MAY NEAR THE SITE. DUE TO THE RAINFALL AND THE SOUTHEAST WINDS BRINGING IN HIGHER DEW POINTS AROUND KGLD TONIGHT...FOG MAY DEVELOP. MOST MODELS ARE NOT INDICATING FOG FORMING ALTHOUGH CLIMATOLOGY IS INDICATING REDUCTIONS ARE POSSIBLE. AS SUCH WILL INCLUDE A MINOR VISIBILITY REDUCTION FOR KGLD OVERNIGHT. MODELS ARE PLACING LIFT OVER KMCK DURING THE MORNING...WITH THE LIFT MOVING EAST FAIRLY QUICKLY. AT THIS TIME WILL NOT INCLUDE A VICINITY TS IN THE TAF DUE TO LOW CONFIDENCE STORMS WILL DEVELOP NEAR THE SITE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...MK AVIATION...JTL
AREA FORECAST DISCUSSION
NWS WICHITA KS
337 AM CDT WED JUN 19 2013 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 330 AM CDT WED JUN 19 2013 TOUGH FORECAST WAS MADE EVEN MORE DIFFICULT DUE TO THE UNAVAILABILITY OF HRRR/00 UTC ECMWF AND RUC AFTER 0600 UTC DUE TO PROBLEMS UPSTREAM. NONE OF THE REMAINDER OF AVAILABLE GUIDANCE HAD MUCH OF A HANDLE ON ONGOING CONVECTION. NAM WAS PARTICULARLY SUSPECT...ESPECIALLY WITH INITIALIZATION OF 850MB MOISTURE. BASED ON 0000 UTC RADIOSONDE OBSERVATION AND OBSERVATIONAL DATASETS... SEE LITTLE REASON WHY HIGH PLAINS CONVECTION WILL NOT CONTINUE TO ROLL EAST DURING THE DAY AIDED BY WARM AIR ADVECTION...INFLUX OF MOISTURE AND SHORTWAVE. EFFECTS ON TEMPERATURES/WINDS DURING THE DAY WILL BE DIFFICULT TO PIN DOWN. THINKING THAT PRECIPITATION WILL TRANSITION TO EASTERN HALF BY LATE AFTERNOON...WITH LULL IN THE WESTERN HALF AROUND SUNSET. SEE NO REASON WHY STORMS WILL NOT DEVELOP OVER THE HIGH PLAINS AGAIN TONIGHT AND ROLL EAST. THU REMAINS PROBLEMATIC...AS IT IS UNCLEAR HOW WIDESPREAD CONVECTION WILL BE OR LOW LONG IT WILL LINGER. LARGE POTENTIAL FOR ERROR ON ALL FACETS OF THIS FORECAST. HAVE LEANED A BIT TOWARDS THE GFS WHICH WAS THE LEAST WRONG GUIDANCE OUT OF THE BOX. HAVE STAYED THE COURSE WITH DRY/WARMER/WINDIER CONDITIONS ON FRIDAY. -HOWERTON .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 330 AM CDT WED JUN 19 2013 THE WARMING TREND WILL CONTINUE INTO THE WEEKEND AS RIDGE BUILDS. SOME HINT ON THE LATEST AVAILABLE GUIDANCE THAT FRONT MAY SAG CLOSE ENOUGH TO BRING SMALL CHANCES FOR PRECIPITATION ON SUN/SUN NIGHT. NOT OVERLY OPTIMISTIC ABOUT THESE CHANCES BUT IN ABSENCE OF 0000 UTC ECMWF WILL NOT MAKE SIGNIFICANT CHANGES. HAVE HEDGED TEMPERATURES UP A BIT ABOVE INITIALIZATION GRIDS BASED ON LAST WARM PERIOD AND BEST GUIDANCE AT THESE TIME RANGES. TEMPERATURES IN TRIPLE DIGITS APPEAR PROBABLE IN CENTRAL KS BY EARLY NEXT WEEK. -HOWERTON && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1247 AM CDT WED JUN 19 2013 TSRA CLUSTER CONTINUING TO MOVE SE~20KTS OVER SC KS SHOULD PASS PRIMARILY ALONG & W OF I-135 THRU ~07Z. NO CIG & VSBY RESTRICTIONS HAVE BEEN ASSOCIATED WITH THE (+)TSRA & HAVE THEREFORE KEPT KICT IN VFR STATUS BUT WINDS ASSOCIATED WITH THE TSRA HAVE BEEN VARIABLE IN BOTH SPEEDS & DIRECTIONS SO HAVE ALREADY UPDATED KICT TO ADDRESS THIS ISSUE. INSOLATION COMBINES WITH DAMP GROUNDS TO ENABLE CUMULUS TO REDEVELOP OVER ALL 5 TERMINALS ~18Z. PERSISTENT LWR-DECK TROF AXIS THAT IS CLOSELY ALIGNED WITH CO/KS BORDER SHOULD ENABLE WINDS TO BECOME DUE SLY & INCREASE TO ~20KTS SUSTAINED WITH GUSTS ~30KTS OVER MOST AREAS ~18Z. && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 84 70 90 73 / 40 40 30 10 HUTCHINSON 87 69 91 72 / 40 50 20 10 NEWTON 85 68 89 72 / 40 40 30 10 ELDORADO 83 69 88 73 / 40 40 40 10 WINFIELD-KWLD 84 70 89 73 / 40 40 30 10 RUSSELL 89 68 94 71 / 50 50 10 10 GREAT BEND 89 68 93 72 / 50 50 10 10 SALINA 88 70 90 75 / 40 50 30 10 MCPHERSON 87 69 90 72 / 40 50 30 10 COFFEYVILLE 90 69 86 73 / 40 30 30 10 CHANUTE 88 68 84 72 / 40 30 30 10 IOLA 88 68 83 71 / 40 40 30 10 PARSONS-KPPF 89 69 84 72 / 40 30 30 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
455 AM EDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 409 PM EDT TUE JUN 18 2013 WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES BETWEEN A TROUGH OVER QUEBEC AND A RIDGE FROM THE ROCKIES INTO THE WRN PLAINS. AT THE SFC...A RIDGE EXTENDED FROM JAMES BAY TO LAKE SUPERIOR. WITH THE DRY AIRMASS OVER THE REGION (PWAT AROUND 0.50 OR ABOUT 50 PCT OF NORMAL)...A WEAK SHORTWAVE TROUGH INTO WRN LAKE SUPERIOR ONLY SUPPORTED A PATCH OF MID/HIGH CLOUDS. TONIGHT...HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION KEEPING CONDITIONS DRY UNDER MOSTLY CLEAR SKIES. AS THE RIDGE AXIS SLIDES SE OVERNIGHT...LIGHT RETURN SRLY FLOW WILL RESULT IN A BIT MORE MIXING ESPECIALLY OVER THE FAR WEST AND ALONG THE LAKE SUPERIOR SHORELINE. LOOK FOR MIN TEMPS TO RANGE FROM AROUND 40 INLAND TO THE MID TO UPPER 40S ALONG THE GREAT LAKES SHORELINES. WEDNESDAY...AS THE RIDGE SLOWLY SLIDES OFF TO THE EAST...SRLY WINDS WILL INCREASE. 850 MB TEMPS AROUND 10C AND MIXING TO AROUND 800 MB WILL SUPPORT TEMPS INTO THE MID 70S INLAND...EXCEPT NEAR LAKE MICHIGAN WHERE ONSHORE FLOW KEEPS READINGS IN THE 60S. ALTHOUGH MOISTURE WILL ALSO INCREASE SLIGHTLY...THE HIGHER LOW LEVEL THETA-E AXIS TO SUPPORT SHRA/TSRA WITH WEAK SHRTWVS IN NW FLOW IS EXPECTED TO REMAIN WEST OF THE CWA. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 409 PM EDT TUE JUN 18 2013 AREA WILL BE UNDER NORTHWEST FLOW ALOFT TO START THE PERIOD AS THE UPPER GREAT LAKES IS ON THE EASTERN SIDE OF THE RIDGE OVER THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. A WEAK SHORTWAVE WILL BE SLIDING ACROSS NORTHEAST LAKE SUPERIOR ON WEDNESDAY NIGHT...WHILE A SURFACE TROUGH DROPS SOUTHEAST ACROSS THE CWA DURING THE OVERNIGHT PERIOD. THERE WILL LIKELY BE SOME SHOWERS AND A FEW THUNDERSTORMS WITH THIS TROUGH ON WEDNESDAY NIGHT AND WILL FOLLOW A GENERAL CONSENSUS FOR THE TIMING OF THE POPS AS IT MOVES IN. THIS FRONT LOOKS TO STALL ACROSS UPPER MICHIGAN ON THURSDAY AND WILL COMBINE WITH DEVELOPING LAKE BREEZES TO PRODUCE AFTERNOON SHOWERS AND THUNDERSTORMS. THE STRENGTH OF THESE THUNDERSTORMS WILL DEPEND ON THE AMOUNT OF DIURNAL HEATING...INCREASING SOUTHERLY FLOW WITH A DEVELOPING WARM FRONT ON THE BOUNDARY...AND THE ARRIVAL OF THE ANOTHER WEAK SHORTWAVE DURING THE LATE AFTERNOON AND EVENING. ML CAPE VALUES OF 500-1000 J/KG OVER THE WESTERN 2/3RDS OF THE CWA AND 0-6KM BULK SHEAR VALUES AROUND 30KTS SUPPORTS THUNDERSTORMS AND SOME TILTING OF THE UPDRAFTS. HEAVY RAIN AND SMALL HAIL WILL BE THE PRIMARY THREATS...AS NCAPE VALUES AROUND .1 SHOULD KEEP ANY HAIL FROM GROWING TOO LARGE. WILL CONTINUE TO HIGHLIGHT THE HIGHEST POPS OVER THE INTERIOR WEST/CENTRAL...CLOSEST TO LAKE SUPERIOR LAKE BREEZE AND THEN FOLLOW THE STORM MOTION TO THE SOUTHEAST. THURSDAY NIGHT THROUGH THE WEEKEND IS SHAPING UP TO BE A FAIRLY ACTIVE PATTERN FOR THUNDERSTORMS IN THE UPPER MISSISSIPPI VALLEY AND UPPER GREAT LAKES REGION. THIS IS DUE TO THE UPPER RIDGE GRADUALLY SHIFTING EAST INTO THE UPPER GREAT LAKES. MEANWHILE...WEAK SURFACE LOW WILL REMAIN FAIRLY STATIONARY OVER THE CENTRAL/NORTHERN PLAINS. FROM THIS LOW...A WARM FRONT WILL LOOKS TO SETUP FROM THE STALLED TROUGH ON THURSDAY AND REMAIN LOCATED AROUND THE UPPER GREAT LAKES REGION THROUGH THE WEEKEND. LOOKING AT THIS LARGE SCALE PATTERN...IT IS VERY CONDUCIVE PERIODS OF SHOWERS AND POTENTIALLY STRONG THUNDERSTORMS. BUT TRYING TO PIN DOWN THE EXACT LOCATION AND TIMING IS DIFFICULT DUE TO THE VARIABILITY OF THE SHORTWAVES AND POSITION OF THE WARM FRONT. INSTABILITY WILL GRADUALLY GROW FROM FRIDAY INTO THE WEEKEND...AS PERSISTENT SOUTHWESTERLY FLOW AHEAD OF THE LOW PULLS PLENTY OF GULF MOISTURE INTO THE AREA. USING ML CAPE VALUES TO REMOVE SOME OF THE LOW LEVEL MOIST BIASES IN THE MODELS FOR FRIDAY INTO THE WEEKEND...THERE ARE STILL SOME DECENT VALUES FOR U.P. STANDARDS. FRIDAY THEY LOOK TO PEAK IN THE 750-1500 J/KG RANGE OVER THE WEST AND THEN GROW TO 1500-2500 J/KG FOR SAT/SUN DEPENDING ON THE MODEL. THE GFS IS THE MOST AGGRESSIVE ON THE NORTHWARD EXTENT OF THE WARM FRONT...WHILE THE GEM/ECMWF TRY TO KEEP THE FRONT A TOUCH SOUTH OF THE AREA. IT WILL PROBABLY BE A VARIETY OF THUNDERSTORM TYPES DURING THAT PERIOD. CONVECTIVE COMPLEXES MOVING EAST /VIA FORWARD PROP CORFIDI VECTORS/ AROUND THE RIDGE WILL LIKELY BE THE MAIN THREAT...BUT WITH THE INSTABILITY PRESENT AND LIMITED INHIBITION...DIURNAL THUNDERSTORMS WILL ALSO BE POSSIBLE. THE ONLY CONCERNS WOULD BE IF THE RIDGE AND WARM FRONT BUILD FAR ENOUGH NORTH TO SLIDE MOST OF THE THUNDERSTORM COMPLEXES NORTH OF UPPER MICHIGAN OR THE MORE LIKELY SCENARIO OF IT BECOMING HUNG UP SOUTH OF THE AREA /ESPECIALLY AS CONVECTION HOLDS THEM SOUTH/. WITH THE GROWING CONFIDENCE...WILL ADD A MENTION OF STRONG THUNDERSTORMS FOR THE WEEKEND IN BOTH THE HWO AND EHWO. HEAVY RAIN IS ALSO POSSIBLE DURING THIS PERIOD WITH THE THUNDERSTORMS...AS PWAT VALUES RISE ABOVE 1.5 INCHES WHICH IS WELL ABOVE THE 75TH PERCENTILE FOR CLIMATOLOGY FOR THIS AREA. IT WILL BE PRETTY HUMID FOR FRIDAY INTO THE WEEKEND /DEWPOINTS IN THE UPPER 50S AND 60S/ AND THE TEMPERATURES WILL DEPEND ON THE POSITIONING OF THE WARM FRONT. WILL CONTINUE TO SHOW TEMPS IN THE MID 70S TO LOWER 80S FOR MOST LOCATIONS...WITH THE WARMEST VALUES NEAR THE WISCONSIN BORDER. IF THE GFS ENDS UP BEING CORRECT...WOULD HAVE TO BUMP TEMPS UP WELL INTO THE 80S FOR THE END OF THE WEEKEND. UNCERTAINTY REALLY GROWS HEADING INTO MONDAY/TUESDAY...AS A LOT DEPENDS ON THE WEEKEND WEATHER. THE GENERAL IDEA FROM THE MODELS IS THAT THE RIDGE BREAKS DOWN AND THE AREA WILL BE UNDER ZONAL FLOW ALOFT. THIS WILL CONTINUE TO BRING WAVES ACROSS THE AREA AND KEEP THE THUNDERSTORM POTENTIAL IN PLACE FOR THAT PERIOD. AT THIS TIME...MODELS ARE INDICATING A COLD FRONT DROPPING SOUTH OUT OF CANADA ON WEDNESDAY...WHICH MAY BRING AN END TO THE WARM/HUMID WEATHER. FINALLY...WILL CONTINUE TO MENTION PATCHY FOG DEVELOPING ON LAKE SUPERIOR ON WEDNESDAY NIGHT AND THEN CONTINUING INTO EARLY NEXT WEEK. WILL LIKELY NEED TO EXPAND IT TO AREAS OR EVEN DENSE FOG AS IT NEARS. ALSO...ADDED A MENTION OF FOG OVER LAKE MICHIGAN NEARSHORE AREAS STARTING LATE THURSDAY NIGHT AS THE PRECIPITATION AND HIGHER DEWPOINTS START TO AFFECT THAT AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1203 AM EDT WED JUN 19 2013 WITH HIGH PRESSURE IN CONTROL...VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THE PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 455 AM EDT WED JUN 19 2013 WINDS SHOULD REMAIN BELOW 25KTS THROUGH THE PERIOD...WITH RELATIVELY LOW WAVES. THE MAIN THREAT WILL BE STRONG WINDS/HAIL/LIGHTNING WITH ANY THUNDERSTORMS MOVING ACROSS LAKE SUPERIOR FROM LATE TONIGHT THROUGH THE WEEKEND AND BEYOND...AND PATCHY TO AREAS OF FOG THAT DEVELOP AS A RESULT OF INCREASED MOISTURE AND SHOWER ACTIVITY. HIGH PRESSURE CENTERED OVER LAKE HURON WILL CONTINUE TO SINK SOUTHEASTWARD...AS A LOW OVER NORTHERN ONTARIO SWINGS INTO QUEBEC. A TROUGH EXTENDING FROM THE CANADIAN LOW WILL DRIFT ACROSS LAKE SUPERIOR LATE TONIGHT INTO THURSDAY. THE TROUGH SHOULD STRENGTHEN THURSDAY NIGHT THROUGH SATURDAY...AS HIGH PRESSURE PUSHES ACROSS ONTARIO...AND AN ELONGATED AREA OF LOW PRESSURE ORGANIZES ACROSS THE NORTHERN AND CENTRAL PLAINS. THE TROUGH WILL FURTHER DEEPEN OVER LAKE SUPERIOR ON SUNDAY AS THE MAIN LOW PUSHES NORTHWARD THROUGH THE DAKOTAS AND INTO SOUTH CENTRAL CANADA. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
414 AM CDT WED JUN 19 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 410 AM CDT WED JUN 19 2013 CIRRUS SHIELD NOTED ON IR SATELLITE ENTERING FAR WESTERN MN. SHIELD IS JUST AHEAD OF DEEPENING SURFACE CYCLONE ABOVE EASTERN MONTANA. THIS FEATURE WILL BE EJECTED OUT OF 50H TROF OVER PACIFIC NW DURING THE NEXT 24 HOURS INTO WESTERN NODAK AND SOUTHERN SASKATCHEWAN. WARM FRONTAL BOUNDARY ATTACHED TO SURFACE CYCLONE WILL BE CATALYST FOR SCATTERED SHOWERS AND ISOLATE THUNDERSTORMS LATE THIS MORNING OVER FAR WESTERN CWA. USED GFS40 THETA E ADVECTION AND HRRR GUIDANCE FOR PLACEMENT AND TIMING OF DAYTIME CONVECTION OVER FA. COULD BE A FEW STRONG TO NEAR SEVERE THUNDERSTORMS THIS AFTERNOON OVER CENTRAL AND PORTIONS OF SW MN TO...AS JOULES INCREASE INTO THE 1500 TO 2500 RANGE. MODERATE 250MB DIVERGENCE COUPLETS ALSO NOTED OVER THESE AREAS ALONG WITH LI`S PLUNGING INTO THE NEGATIVE 4 TO NEGATIVE 8 CATEGORY. ONLY LIMITING FACTOR WOULD BE THICKER CLOUD DECK THEN CURRENT CIRRUS SHIELD PROGGED FOR MUCH OF THE DAYTIME HOURS. PRESENCE AND PROGRESSION OF WARM FRONTAL BOUNDARY DEEPER INTO SOUTHERN HALF OF MN TONIGHT SHOULD PORTEND SLIGHTLY ENHANCED CHANCES FOR CONVECTION...WITH QPF VALUES ALSO RISING NOTICEABLY. COULD BE A QUICK QUARTER INCH TO ONE HALF INCH OF MOISTURE GENERATE FROM CONTINUE SCT ACTIVITY DURING THE OVERNIGHT. 850MB LAPSE RATES AND LI`S WILL ALSO RISE SLIGHTLY OVERNIGHT. MODERATE SOUTHERLY LOW LEVEL JET WILL ALSO FORM BY LATE TONIGHT OVER MUCH OF MN FA ...WITH 25 TO 30KT MAGNITUDES COMMON SOUTH OF A LINE FROM ALEXANDRIA TO OWATONNA. COULD BE ADDITIONAL ISOLATED STRONG TO NEAR SEVERE T-STORMS OVER WESTERN HALF OF FA DURING THE EVENING...SWITCHING TO FAR EAST CENTRAL MN/WEST CENTRAL WI AFTER MIDNIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 410 AM CDT WED JUN 19 2013 WARM AND MOISTURE-RICH PATTERN WILL REMAIN IN PLACE FOR THE END OF THIS WEEK INTO THE START OF NEXT WEEK...INCLUDING PERIODS OF STRONG THUNDERSTORMS AND HEAVY RAIN. AN UPPER LEVEL RIDGE BUILDING OVER THE DAKOTAS AND MN/WI THRU TDA WILL SHIFT TO THE E THRU THU WHILE A LONGWAVE TROUGH DEVELOPS OVER THE NORTHWEST. SEVERAL SHORTWAVE DISTURBANCES RIDING NOT ONLY OVER TOP THE RIDGE BUT ALSO AROUND THE BASE OF THE TROUGH THU INTO FRI WILL WORK WITH AN INCOMING SFC FRONTAL SYSTEM DEVELOPING OVER THE CENTRAL-NRN PLAINS. SOLID SW FLOW WILL BRING NOT ONLY WARMER AIR /WHICH WILL RAISE H5 HEIGHTS TO ENHANCE CAPPING BUT ALSO STRONGER JETTING/ BUT ALSO MOISTURE-RICH AIR /HELPING RAISE PWATS ABOVE 1.50 INCHES AND ENHANCE INSTABILITY/...AND THE SFC FRONTAL WAVES COMBINED WITH UPPER LEVEL DISTURBANCES WILL ALLOW FOR PERIODS OF CONVECTION. THURSDAY CONTINUES TO BE HIGHLIGHTED BY SPC INVOF THE APCHG CDFNT FOR THE WRN HALF OF MN. ONCE THE CAPPING INVERSION IS LOST OVER WRN MN...STRONG MID- AND UPPER-LEVEL JETTING WITH STEEP LAPSE RATES WITHIN A HIGHLY UNSTABLE ENVIRON /INCLUDING DEWPOINTS NEAR- OVER 70 DEGREES/ WILL PROMOTE STRONG TO SEVERE TSTMS CAPABLE OF PRODUCING LARGE HAIL AND DMGG WINDS. THE REGIME THEN TRANSITIONS TO ONE OF HEAVY RAIN OVER THE WEEKEND AS THE SFC LOW PRES SYSTEM OPENS UP AND BECOMES CAUGHT UP IN THE PROLIFIC SWLY FLOW WHILE THE NW UPPER LEVEL TROUGH OPENS TO MORE OF A TROUGH THAN CUTOFF LOW. LONG PLUME OF SLY SFC FLOW WILL AID IN BRINGING MOISTURE WELL N INTO THE UPPER MISS RIVER VALLEY REGION. MODEL QPF CONTINUES TO ADVERTISE BETWEEN 3 AND 6 INCHES OF RAIN FOR THE AREA THROUGH THE WEEKEND...BUT WITH MUCH OF IT CONVECTIVE...TRYING TO PINPOINT WHERE SUCH RAINFALL EVENTS MAY OCCUR IS HIGHLY PROBLEMATIC. STILL...HAVE KEPT HIGH-END CHC POPS GOING IN THE FCST. POPS DIMINISH FOR THE START OF NEXT WEEK AS A MORE ZONAL UPPER LEVEL PATTERN DEVELOPS...KEEPING ANY ORGANIZED LOW PRES SYSTEMS AWAY FROM THE AREA. THAT SAID...SEVERAL MID- AND UPPER-LEVEL SHORTWAVE DISTURBANCES WILL STILL BE CAPABLE OF PRODUCING ISOLD TO SCATTERED CONVECTION AS THE WARM/MOIST AIR WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1137 PM CDT TUE JUN 18 2013 VFR CONDITIONS TONIGHT AND FOR MOST OF THE AREA WEDNESDAY. POTENTIAL FOR FOG TONIGHT HAS DIMINISHED SUCH THAT IT HAS BEEN REMOVED FROM THE TAFS. A FEW THUNDERSTORMS MAY DEVELOP WEDNESDAY AFTERNOON ACROSS MN...BUT THEY SHOULD REMAIN FAIRLY ISOLATED AND SHORT-LIVED SO WAS NOT CONFIDENT ENOUGH TO INCLUDE MENTION IN ANY TAFS. IF IT DOES HIT A TAF SITE...BRIEF MVFR CONDITIONS WOULD BE LIKELY. WINDS WILL VEER SOUTHERLY AND STRENGTHEN WEDNESDAY...BEFORE DIMINISHING AND BACKING SOUTHEASTERLY DURING THE EVENING. KMSP...VFR EXPECTED THROUGH THE PERIOD. LITTLE WX IMPACT EXPECTED THROUGH MOST OF WED...BUT THERE IS AN OUTSIDE CHANCE OF A LATE DAY STORM. WIND WILL INCREASE SOUTHERLY AND COULD GUST TO NEARLY 20 KT WEDNESDAY. /OUTLOOK FOR KMSP/ THU...VFR. CHC OF MVFR. TSRA LIKELY. SSE WINDS 10 KTS. FRI...VFR. CHC OF MVFR TSRA. S WINDS 10-15 KTS. SAT...VFR. CHC OF MVFR TSRA. S WINDS 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...AJZ LONG TERM...JPC AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1151 PM MDT TUE JUN 18 2013 .AVIATION... 06Z TAF CYCLE CONVECTION ACROSS NE NM EXITED THE AREA LATE THIS EVENING. APPEARS THAT A BOUNDARY HAS MOVED NWWD THRU KSAF...BUT CONFIDENCE REMAINS LOW THAT A CANYON WIND WILL DEVELOP IN THE ABQ AREA TONIGHT DUE TO THE LACK OF CONVECTION FARTHER SOUTH ACROSS THE EASTERN PLAINS. HAVE REMOVED THE EAST WIND IN THE ABQ TAF FOR NOW...BUT IT BEARS WATCHING...AS A MODERATE PRESSURE GRADIENT REMAINS IN PLACE. OTHERWISE...CANT RULE OUT SOME LOW CIGS DEVELOPING ACROSS THE NORTHEAST PLAINS AFTER 09Z...ESPECIALLY IN AREAS THAT RECEIVED APPRECIABLE RAINFALL. BREEZY TO WINDY CONDITIONS WILL DEVELOP LATE WEDNESDAY MORNING...WITH GUSTS BETWEEN 35 AND 40KTS POSSIBLE THROUGH EARLY EVENING. SOME MODELS ARE INDICATING CONVECTION REDEVELOPING WEDNESDAY EVENING ACROSS THE FAR EASTERN PLAINS. HOWEVER...HAVE NOT INSERTED A VCTS MENTION ATTM AS CONFIDENCE IS LOW THAT ANY TAF SITE WILL BE IMPACTED...THOUGH TCC AND ROW HAVE THE BEST CHANCES. 34 && .PREV DISCUSSION...926 PM MDT TUE JUN 18 2013... ALLOWED SEVERE THUNDERSTORM WATCH TO EXPIRE AS SCHEDULED WITH STORMS JUST IN UNION COUNTY AT THIS TIME. JURY STILL OUT ON WHETHER WE WILL SEE MUCH OF AN EAST WIND INTO THE RGV LATER TONIGHT...SETUP DIFFERENT THAN LAST NIGHT. RUC13 HAS BEEN BACKING OFF ON A STRONG GRADIENT UNTIL AFTER MIDNIGHT OR EVEN TOWARDS SUNRISE. WILL KEEP MONITORING. ZFP ALREADY OUT. .PREV DISCUSSION...307 PM MDT TUE JUN 18 2013... ...SEVERE THUNDERSTORM WATCH 325 IN EFFECT UNTIL 9 PM MDT... STORM COVERAGE IS MUCH MORE LIMITED TODAY AS POTENT DRY AIR ALOFT MOVES OVER THE REGION ON INCREASING SOUTHWESTERLY FLOW. LOW LEVEL MOISTURE DID MAKE IT ALL THE WAY TO THE DIVIDE BUT IT IS SHALLOW AND WILL CONTINUE MIXING OUT THIS AFTERNOON. THIS GRADIENT ACROSS THE AREA ALONG WITH AFTERNOON HEATING AND TOPOGRAPHIC FORCING WILL SET THE STAGE FOR SEVERE STORMS OVER THE NE PLAINS. LATEST RADAR TRENDS SHOW A POTENTIAL SEVERE STORM WEST OF RATON...AND THIS IS EXPECTED TO CONTINUE THROUGH THE EVENING AS THE ATMOSPHERE BECOMES MORE UNSTABLE. RAISED POPS FOR THE NE AND EAST CENTRAL PLAINS AND LOWERED A LITTLE FARTHER WEST. WEDNESDAY WILL BE AN UGLY FIRE DANGER DAY ACROSS THE REGION WITH DEEP MIXING TAPPING VERY DRY AIR LEADING TO HOT...BREEZY/WINDY... AND UNSTABLE CONDITIONS. 700MB TEMPS WILL BE NEAR +18C WHICH IS NOT AS WARM AS WHAT WE EXPERIENCED LAST WEEK HOWEVER IT IS STILL WELL ABOVE NORMAL. TOSSED IN SOME SYNOPTICALLY DRIVEN BLOWING DUST INTO THE GRIDS FOR A FEW CENTRAL AND WESTERN LOCALES. ANY STORMS WILL BE FOCUSED ACROSS THE PLAINS AND EVEN THERE EXPECT MOSTLY DRY AND GUSTY ACTIVITY. THURSDAY WILL BE SIMILAR TO WEDNESDAY EXCEPT MORE MOISTURE WILL TRICKLE NORTH ACROSS THE SE HALF OF THE AREA. RAISED POPS JUST A TAD FARTHER NORTH AS THE 12Z NAM IS BULLISH ON DEVELOPING ACTIVITY UP TO THE I-40 CORRIDOR. TEMPS WILL REMAIN HOT AND WINDS ALOFT WILL STAY STRONG SO BREEZY CONDITIONS CAN BE EXPECTED. ANY SHOWERS/STORMS THAT GET GOING WILL HAVE POTENTIAL TO PRODUCE STRONG OUTFLOW WINDS. QUITE A LARGE AMOUNT OF UNCERTAINTY REMAINS WITH MEDIUM/EXTENDED RANGE GUIDANCE FOR FRIDAY THRU EARLY NEXT WEEK. THE GFS ENSEMBLE PWAT SHOWS A LARGE SWATH OF 1-2 STDEV BELOW CLIMO VALUES FROM THE NORTHERN BAJA REGION ACROSS THE GREAT BASIN...WITH NEAR CLIMO VALUES FOR NM. THE ECMWF IS SIGNIFICANTLY DRIER THRU THIS PERIOD WITH THE UPPER RIDGE AXIS STRETCHING FROM WSW TO ENE ACROSS NORTHERN MEXICO. THIS SHUTS OFF ANY STREAM OF MOISTURE SLIDING INTO OUR AREA THRU ALL OF NEXT WEEK WITH A 598DM RIDGE BUILDING RIGHT OVER NORTHERN NM AND SOUTHERN CO. THIS WOULD LEAD TO WELL ABOVE NORMAL SCORCHING TEMPS ONCE AGAIN. THE GFS HOWEVER DOES TAKE A PIECE OF THE CURRENT TROPICAL DISTURBANCE OVER SOUTHERN MEXICO AND LIFTS IT NORTH WITH THE RIDGE FARTHER EAST. FOR NOW WILL SIDE WITH THE DRIER SOLUTION AND KEEP POPS VERY LOW IN THE EXTENDED. GUYER .FIRE WEATHER... ...CRITICAL FIRE WEATHER PERIOD NEXT FEW DAYS... MODEL GUIDANCE HAS SUGGESTED A LITTLE STRONGER FLOW FOR PORTIONS OF THE FORECAST AREA WEDNESDAY SO RAISED SPEEDS SLIGHTLY BUT PRETTY SIMILAR TO ORIGINAL LEVELS. THE HIGHER RIDGES AND AREAS NEAR THE AZ/CO STATE LINES AS WELL AS TO THE LEE OF THE CENTRAL MOUNTAINS WILL BE FAVORED FOR THE STRONGEST WINDS. LATEST MODEL GUIDANCE ALSO SUGGEST THE STRONGEST WINDS ALOFT WEDNESDAY NIGHT INTO THURSDAY SO BUMPED UP WIND SPEEDS ACCORDINGLY. GETTING MORE CRITICAL FIRE WEATHER CONDITIONS FOR THURSDAY. ONLY FLY IN THE OINTMENT IS THE 12Z NAM/S DEPICTION OF MID LEVEL MOISTURE FLOWING UP FROM MEXICO THURSDAY AFTERNOON. OTHER MODELS NOT AS AGGRESSIVE. COULD BE A WILD AND WOOLLY DAY WITH A MIX OF STANDARD RED FLAG CONDITIONS PLUS DRY MICROBURST WINDS DUE TO DRIER STORMS. WILL MONITOR THAT TREND ACCORDINGLY. WILL UPGRADE WATCH TO A WARNING FOR THE ENTIRE FORECAST AREA EXCLUDING AREAS NEAR TO THE TEXAS STATE LINE DUE TO HIGHER RH THERE WEDNESDAY. WILL ISSUE A WATCH FOR THE WESTERN TWO THIRDS OF THE FORECAST AREA ON THURSDAY. GOING TO BE ON THE SAFE SIDE FOR BOTH DAYS. AS FAR AS REST OF TODAY...LOOKING AT SOME DRIER STORMS ACROSS THE NORTH CENTRAL MOUNTAINS AS THE DRY AIR RAPIDLY PUSHES FROM WEST TO EAST. THESE STORMS WILL TEND TO BE FAST MOVING. THE WETTER STORMS WILL BE FOUND ACROSS THE EASTERN PLAINS...ESPECIALLY FAVORING THE NORTHEAST. UPPER FLOW WILL INCREASE OVER NORTHERN AND CENTRAL NEW MEXICO TONIGHT AS THE UPPER RIDGE SLIDES SLIGHTLY TO THE EAST. TEMPERATURES WILL BE ABOVE NORMAL. THE MID LEVEL DRY INTRUSION WILL FILTER FURTHER OVER THE FORECAST AREA ALTHOUGH ABUNDANT LOW LEVEL MOISTURE WILL TRY TO PUSH BACK TO THE WEST SIMILAR TO LAST NIGHT BUT NOT AS AGGRESSIVE. HUMIDITY RECOVERIES WILL BE VERY POOR NEAR TO THE AZ STATE LINE...POOR BETWEEN THE CONTINENTAL DIVIDE TO RIO GRANDE VALLEY AND THEN MODERATE TO GOOD FURTHER EAST. EVEN EXCELLENT NEAR THE TEXAS STATE LINE. WEDNESDAY WILL BE A HIGHER END CRITICAL DAY DUE TO THE TIME OF YEAR AND COMBO WIND/LOW RH/ABUNDANT TURBULENT MIXING AND QUITE A BIT OF SUNSHINE. SUN ANGLES ARE GETTING TO BE QUITE STEEP AND THE MID LEVEL DRY INTRUSION IS EXPECTED TO BE QUITE STRONG AS IT PUSHES FURTHER EASTWARD OVER THE STATE. SUPER HAINES VALUES ARE PROJECTED FOR WESTERN AND NORTHERN NEW MEXICO. THE SURFACE WIND FLOW WILL BE HERKY JERKY OR PULSY DUE TO THE TURBULENT MIXING AND ABOVE NORMAL TEMPERATURES. MIXING HEIGHTS ARE PROJECTED TO BE ABOVE NORMAL WITH SOME PRETTY STOUT SOUTHWEST TRANSPORT WINDS. SEVERAL HOURS OF SINGLE DIGITS ARE EXPECTED ALONG AND JUST TO THE LEE OF THE CENTRAL MTNS WESTWARD TO ARIZONA. THE HEART OF THE SINGLE DIGIT AREA IN TERMS OF 10 TO 15 HOURS INCLUDES THE NORTHWEST HALF OF THE FORECAST AREA. STORM POTENTIAL...MAINLY OF THE DRIER VARIETY WILL BE FOUND ACROSS THE EASTERN PLAINS AND CANT RULE OUT A ROGUE DRY STORM ALONG THE EAST SLOPES OF THE SANGRES BEFORE THE DRY AIR REALLY PUSHES IN. THE RIDGE WILL NUDGE A LITTLE FURTHER TO THE EAST WEDNESDAY NIGHT AS THE MID LEVEL DRY INTRUSION PROCEEDS OVER THE ENTIRE AREA. TEMPERATURES WILL REMAIN WARMER THAN NORMAL WITH POOR TO VERY POOR RECOVERIES WESTERN TWO THIRDS OR SO. MUCH BETTER RECOVERIES WITH RESIDUAL HIGHER LOW LEVEL MOISTURE WILL BE FOUND NEAR THE TEXAS STATE LINE. THE HIGHER RIDGES SHOULD CONTINUE TO SEE STEADY WIND FLOWS AS THE UPPER FLOW STRENGTHENS SOME. THIS WILL LEAD INTO ANOTHER POTENTIALLY CRITICAL DAY ON THURSDAY. THE UPPER FLOW WILL REMAIN PRETTY STRONG AND FAVOR THE SAME AREAS AS MENTIONED DURING THE OPENING PARAGRAPH. TEMPERATURES WILL REMAIN ABOVE NORMAL ALTHOUGH HUMIDITY VALUES COULD RISE SOME AS COMPARED TO WEDNESDAY/S READINGS. NAM MODEL A LITTLE JUMPY WITH ITS DEPICTION OF A MID LEVEL MOISTURE PUSH FROM MEXICO. THE 12Z MODEL WAS MORE MOIST WHILE THE 18Z IS COMING IN DRIER. IF STORMS DO FORM THEY WOULD BE DRIER AND FASTER MOVING LEADING TO AN ADDITIONAL IGNITION THREAT. EITHER WAY...GETTING ENOUGH CRITICAL WIND SPEEDS COMBINED WITH LOW HUMIDITY AND ABOVE NORMAL MIXING TO WARRANT A FIRE WEATHER WATCH. SEEING A SUPER HAINES SIGNATURE ACROSS THE NORTHWEST THIRD OR SO BUT LESS AREA THAN IS EXPECTED WEDNESDAY. EXTENDED MODELS SUCH AS THE GFS AND ECMWF POINT TOWARDS AN UPPER SOUTHWEST FLOW CONTINUING FRIDAY AND INTO THE WEEKEND. DECIDED TO UP WIND SPEEDS SLIGHTLY FOR FRIDAY AND SEEING SOME LOCALIZED CRITICAL CONDITIONS BUT DOESNT APPEAR TO BE AS STRONG OF A SIGNAL AS THE PREVIOUS DAYS. UPPER FLOW IS DEPICTED TO WEAKEN SOME AS THE PACIFIC TROUGH SHEARS OUT. EXPECTING SOME SORT OF MID LEVEL MOISTURE SEEPAGE FROM MEXICO DURING THIS PERIOD WITH MORE OF A MOISTURE RETURN FROM THE GULF ACROSS THE SOUTHEAST AND EAST CENTRAL PLAINS. THE WETTER STORMS COULD BE POSSIBLE THERE WHILE THE DRIER VARIETY ELSEWHERE. TEMPERATURES WOULD BE A FEW DEGREES ABOVE NORMAL DURING THIS PERIOD WITH MUCH LOWER HUMIDITY VALUES WEST. CONFIDENCE IN THIS PERIOD IS MODERATE ALTHOUGH LOTS OF UNCERTAINTY ON THE MOISTURE PUSH. 50 && .ABQ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TO 8 PM MDT WEDNESDAY FOR THE FOLLOWING ZONES...NMZ101>109. FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR THE FOLLOWING ZONES...NMZ101>103-105>107-109. && $$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
840 PM EDT TUE JUN 18 2013 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO CENTRAL NC FROM THE NORTH WEDNESDAY THROUGH THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 250 PM TUESDAY... SLIGHT TO MODERATELY UNSTABLE AIR MASS RESIDES OVER CENTRAL NC AT MID-AFTERNOON THANKS TO PEAKS OF SUN HEATING UP AN AIR MASS WITH SFC DEWPOINTS IN THE UPPER 60S TO LOWER 70S. UPSTAIRS...A VORT MAXIMUM OVER THE CENTRAL APPALACHIANS CONTINUES TO ROTATE EASTWARD WITH ATTENDANT SHEAR AXIS EXTENDING SWWD ALONG THE SPINE OF THE SOUTHERN APPALACHIANS. THIS MID LEVEL FEATURE AIDING TO ENHANCE THE 925-850MB FLOW WHICH IS ADVECTING ADDITIONAL MOISTURE INTO THE COLUMN. LATEST SATELLITE TOTAL BLEND PRECIP WATER PRODUCT DEPICTS VALUES BETWEEN 1.8-2 INCHES OVER OUR FORECAST AREA. THOUGH MID LEVEL LAPSE RATES ARE MEAGER...ENOUGH JUICE EXISTS IN THE ATMOSPHERE TO SUPPORT THE DEVELOPMENT OF NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS LATE THIS AFTERNOON THROUGH EARLY EVENING AS THE MID LEVEL SHEAR AXIS CROSSES THE REGION. CURRENT 0-6KM SHEAR VALUES IN THE 30-40KT RANGE OVER THE NW PIEDMONT SUPPORT THE IDEA OF CONVECTION FORMING INTO A LINE AS IT MARCHES EAST-SE. CANNOT RULE OUT THE POSSIBILITY OF AN ISOLATED STRONG-SEVERE STORM WITH WIND GUSTS 40-50 MPH. STILL BELIEVE MAIN WEATHER HAZARD WILL BE TORRENTIAL DOWNPOURS WITH RAINFALL RATES 2-3 INCHES PER HOUR POSSIBLE IN A FEW OF THE STORMS. FORTUNATELY STEERING WINDS CLOSE TO 25KTS SO STORMS WITH THIS MAGNITUDE OF RAIN SHOULD NOT SETTLE OVER ONE SPOT VERY LONG. BULK OF CONVECTIVE ALLOWING MODELS AS WELL AS THE 11Z HRRR SUGGEST THE BROKEN LINE OF CONVECTION CROSSING THE PIEDMONT BETWEEN 21Z-00Z...AND INTO THE SANDHILLS AND COASTAL PLAIN 23Z-02Z. PLAN TO MAINTAIN CATEGORICAL POPS IN THE NW PIEDMONT LATE THIS AFTERNOON THEN SPREAD THESE HIGHER POPS SEWD WITH TIME. WILL INTRODUCE DECREASING POPS BY EARLY EVENING IN THE NW PIEDMONT...THEN TREND POPS LOWER OVER THE REMAINDER OF THE FORECAST BETWEEN 02Z-06Z. OVERNIGHT...SFC COLD FRONT WILL PROGRESS SEWD AND SHOULD LIE WSW-ENE ACROSS OUR FAR SOUTHERN-SE COUNTIES AT DAYBREAK. THIS FEATURE SHOULD INTERACT WITH AVAILABLE MOISTURE TO TRIGGER SCATTERED SHOWERS OVERNIGHT. STILL MUGGY OVERNIGHT THOUGH THE FAR N-NW SECTIONS MAY START TO FEEL A LITTLE LESS HUMID BY DAYBREAK. MIN TEMPS MID 60S TO NEAR 70. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 250 PM TUESDAY... STRONGER S/W IN THE NORTHERN STREAM WILL CROSS THE NORTHERN MID ATLANTIC WHILE THE TAIL END OF THE SHEAR AXIS APPROACHES OUR NORTHERN COUNTIES BY EARLY EVENING. NLY FLOW BEHIND THE INITIAL MID LEVEL TROUGH WILL ADVECT DRIER AND SLIGHTLY MORE STABLE AIR INTO CENTRAL NC. WHILE CLOUDS WILL LIKELY STICK AROUND DUE TO RESIDUAL MOISTURE AND CYCLONIC CURVATURE IN THE MID LEVEL FLOW...CONVECTIVE COVERAGE SHOULD BE LESS NUMEROUS WEDNESDAY AFTERNOON AND NOT AS ROBUST. EXPECT TWO MAIN AREAS OF PRECIP...ONE OVER THE FAR SOUTH IN VICINITY OF THE NEARLY STATIONARY SFC FRONT...AND THE OTHER OVER THE FAR NORTH AHEAD OF THE SWD ADVANCING MID LEVEL SHEAR AXIS. PLAN TO CAP POPS NO HIGHER THAN 50 PERCENT (NEAR SC BORDER) WITH A 1-IN-3 CHANCE ACROSS THE NORTH. AS ATMOSPHERE STABILIZES IN THE EARLY EVENING...EXPECT MAJORITY OF THE CONVECTION TO DISSIPATE THOUGH A STRAY SHOWER MAY STILL OCCUR IN VICINITY OF THE SHEAR AXIS ACROSS THE NORTH. THIS SHEAR AXIS WILL CONTINUE TO PROGRESS SE OVERNIGHT AND EXIT THE REGION BY DAYBREAK THU. SUBSIDENCE BEHIND THIS FEATURE WILL AID TO DISSIPATE THE CLOUD COVERAGE AFTER MIDNIGHT. EXPECT A FAIRLY UNIFORM TEMP FIELD WEDNESDAY DUE TO CLOUD COVERAGE AND LOW LEVEL COLD AIR ADVECTION. MAX TEMPS NEAR 80 NORTH TO LOWER 80S SOUTH. MIN TEMPS WEDNESDAY NIGHT IN THE MID 60S. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AS OF 215 PM TUESDAY... THURSDAY THROUGH FRIDAY...HEIGHTS ALOFT RISE OVER CENTRAL NORTH CAROLINA...WITH A SUBSIDENT AIR MASS IN PLACE OVER THE AREA. PRECIPITABLE WATER VALUES REMAIN HIGHER THURSDAY RELATIVE TO FRIDAY...BETWEEN AN INCH AND 1.5 INCHES ON THE FORMER COMPARED TO A DECREASE FROM THE NORTHEAST TO AT OR BELOW AN INCH FRIDAY. BOTH THE GFS AND NAM BUFR SOUNDINGS...AND PARTICULARLY THE LATTER...FORECAST ENOUGH MOISTURE AROUND 850MB THURSDAY FOR AREAS OF CU TO FORM...MORE LIKELY TOWARD THE WESTERN PIEDMONT WHERE THE 850MB MOISTURE IS HIGHEST. K INDICES FALL FROM THE NORTHEAST AS WELL THURSDAY AFTERNOON CONTINUING INTO FRIDAY...WITH K INDICES WELL INTO NEGATIVE VALUES BY FRIDAY AFTERNOON. IN TERMS OF DEEP CONVECTION...AMPLE OVERALL CIN AND GRADUAL WARMING ALOFT WITH CONVERGENCE ALOFT SHOULD PRECLUDE THAT. THERE SHOULD BE A FEW MORNING GUSTS WITH INITIAL MIXING THURSDAY IN THE LOWER TO MID TEENS KTS IN THE MODESTLY TIGHT GRADIENT BETWEEN AN INVERTED TROUGH OFF OF THE COAST AND SURFACE HIGH PRESSURE BUILDING IN FROM THE NORTHWEST...BUT OVERALL 925MB WINDS ARE MAINLY AROUND 10KT. 1000-850MB THICKNESSES SUGGEST HIGHS IN THE LOWER TO MID 80S BOTH DAYS...CLOSE TO OR ON THE LOWER SIDE OF MOS GUIDANCE. OVERNIGHT LOWS THURSDAY NIGHT AROUND 60 TO THE MID 60S...MINS POSSIBLY TEMPERED A LITTLE OVER THE SOUTHWEST PIEDMONT BY SLIGHTLY GREATER UPPER-LEVEL MOISTURE FORECAST BY BOTH THE NAM AND THE GFS. FRIDAY NIGHT THROUGH TUESDAY...UPPER RIDGING CONTINUES TO BUILD IN. AROUND THE RIDGE...THERE COULD BE A WEAK MID-LEVEL SHORTWAVE OR TWO THAT ATTEMPTS TO MOVE...OR HAS SOME SUCCESS MOVING...INTO CENTRAL NORTH CAROLINA ESPECIALLY LATE IN THE WEEKEND AND EARLY NEXT WEEK. THE MOISTURE OF THE MEAN AIR MASS...AND MOISTURE AT THE SURFACE...INCREASE SUNDAY INTO MONDAY...WITH SURFACE DEW POINTS EXPECTED TO INCREASE TO AROUND 70F BY MONDAY...CONTINUING INTO TUESDAY. WITH SURFACE RIDGING OVER THE GULF CURRENTLY FORECAST...IT SHOULD BE A GRADUAL MOISTURE INCREASE ESPECIALLY AT THE SURFACE...AND COARSE MODEL SOUNDINGS AT LEAST INTO SUNDAY AFTERNOON HAVE A GOOD CONSENSUS OF AT LEAST BEING WEAKLY CAPPED ALOFT. WILL MAINTAIN THE DRY FORECAST FRIDAY NIGHT THROUGH THE WEEKEND...BUT WITH INCREASING MOISTURE...SOME GUIDANCE SUGGESTING A WEAKNESS IN THE MID-LEVEL HEIGHTS TRANSLATING INTO COOLING ALOFT...AT LEAST SOME QPF BY MUCH OF THE CURRENT LONG-TERM GUIDANCE...AND MEX MOS POPS NEAR OR ABOVE CLIMATOLOGY...WILL INTRODUCE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS AT THE END OF THE PERIOD MONDAY AND TUESDAY. FORCING SHOULD BE LIMITED TO WEAK SURFACE TROUGHINESS...SEA BREEZE...AND/OR WEAK MID-LEVEL PVA AT TIMES...WHICH MAY BE ENOUGH FOR ISOLATED SHOWERS AND THUNDERSTORMS IN A RELATIVELY MOIST AIR MASS. 1000-850MB THICKNESSES GRADUALLY RISE...WHICH...ALONG WITH MOS GUIDANCE...WOULD SUGGEST HIGHS RISING TO AT OR ABOVE NORMAL BY SUNDAY. IF THE SURFACE DEW POINT IS A LITTLE HIGHER THAN FORECAST PRIMARILY DUE TO SLIGHTLY LESS MIXING...MAXIMUM AFTERNOON HEAT INDICES COULD RISE TO AROUND 100 BY MONDAY. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... AS OF 840 PM TUESDAY... 24 HOUR TAF PERIOD: A LINE OF HEAVY SHOWERS AND THUNDERSTORMS AHEAD OF A COLD FRONT HAS JUST ABOUT MADE ITS WAY THROUGH KRDU...AND KRWI BUT WILL CONTINUE TO IMPACT KFAY DURING THE NEXT SEVERAL HOURS. WHILE THE THUNDER WILL LINGER NEAR KRWI...THE ACTIVITY SHOULD WANE ENOUGH BY THE TIME THE LINE REACHES KFAY THAT THE MAIN CONCERN WILL BE HEAVY RAIN AND REDUCED VISBYS. THE HEAVY SHOWERS WILL BE ACCOMPANIED BY MVFR/IFR CIGS AND VISBYS...BUT SHOULD BE RELATIVELY SHORT LIVED. THE EFFECTIVE FRONT...AS NOTED BY A VEERING OF THE WINDS FROM SW TO NNW...HAS CROSSED THE TRIAD TERMINALS AS OF 8 PM AND SHOULD MOVE THROUGH THE KRDU/KRWI TERMINALS BETWEEN 8 PM AND 10 PM...AND THE KFAY VICINITY BETWEEN 10 PM AND 1 AM. THE ACTUAL COLD FRONT...ACCOMPANIED BY DROP IN DEWPOINTS...LINGERS A FEW HOURS BEHIND. A BRIEF PERIOD OF MVFR/IFR CIGS IS POSSIBLE BEHIND THE SHOWERS BUT AHEAD OF THE FRONT. -KC AVIATION CONDITIONS WILL BEGIN TO IMPROVE WEDNESDAY MORNING AS DRIER MORE STABLE AIR FLOWS INTO THE REGION BEHIND THE EXITING FRONT. EXPECT A RETURN TO VFR CONDITIONS THOUGH A STRATOCU DECK WILL LIKELY DEVELOP WEDNESDAY AFTERNOON WITH BASES 3000-4000FT. LOOKING AHEAD: HIGH PRESSURE WILL BUILD INTO AND LINGER OVER CENTRAL NC WEDNESDAY NIGHT THROUGH THE WEEKEND. THIS WEATHER SYSTEM WILL BRING DRY AND STABLE CONDITIONS LEADING TO VFR PARAMETERS. THE EXCEPTION WILL BE A BRIEF PERIOD OF MVFR VISIBILITY DUE TO FOG...MAINLY IN THE COASTAL PLAIN. -WSS && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS NEAR TERM...WSS SHORT TERM...WSS LONG TERM...DJF AVIATION...KC/WSS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1233 AM CDT WED JUN 19 2013 .UPDATE... ISSUED AT 1230 AM CDT WED JUN 19 2013 EARLY MORNING RADAR MOSAIC SHOWS THUNDERSTORMS WHICH DEVELOPED ACROSS PARTS OF NORTHWEST SOUTH DAKOTA HAVE DIMINISHED. AN ISOLATED STORM IN THE FAR SOUTHWEST PART OF THE FORECAST AREA CAN NOT BE RULED OUT OVER THE NEXT COUPLE OF HOURS...BUT IT APPEARS THE CHANCES FOR PRECIPITATION ARE DECREASING. MADE SMALL ADJUSTMENTS TO CAPTURE THE LATEST TEMPERATURE TRENDS IN THE UPDATE...OTHERWISE THE FORECAST IS ON TRACK. UPDATE ISSUED AT 916 PM CDT TUE JUN 18 2013 LATEST BOWMAN DOPPLER RADAR SHOWS AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS BEGINNING TO IMPINGE INTO SOUTHWEST HARDING COUNTY IN SOUTH DAKOTA. THE H85-H30 MEAN WIND WOULD CONTINUE TO MOVE THE PRECIPITATION AREA FROM SOUTHWEST TO NORTHEAST THIS EVENING. THE THE LATEST RAP INITIALLY HAS THE AREAL EXTENT OF THE AFOREMENTIONED PRECIPITATION TOO FAR NORTH...AND WILL MAKE ADJUSTMENTS WITH A HEAVIER BLEND OF THE NAM OVERNIGHT. STILL EXPECTING ISOLATED THUNDERSTORMS INTO FAR SOUTHWEST NORTH DAKOTA AS PREVIOUSLY FORECAST...AS A H85-H7 SATURATED POTENTIAL TEMP RIDGE AXIS RESIDES IN CLOSE PROXIMITY IN FAR SOUTHWEST NORTH DAKOTA AND THE ONGOING CONVECTION...ALONG WITH H85-H5 LAPSE RATES OF 7C/KM. THE ACTIVITY SHOULD WEAKEN THEREAFTER...AND HAVE TAPERED OFF POPS TO LESS THAN MEASURABLE INTO SOUTH CENTRAL NORTH DAKOTA OVERNIGHT. ALTHOUGH CLOUD DEBRIS/ACCAS (ALTOCUMULUS CASTELLANUS) SHOULD BE VISIBLE LATER TONIGHT INTO EARLY WEDNESDAY MORNING AS INSTABILITY SHIFTS INTO NORTH DAKOTA. ELSEWHERE...CLOUDS ARE ALSO INCREASING IN NORTHEAST MONTANA AS A CIRRUS CANOPY SHIFTS EAST FROM THE THUNDERSTORMS IN NORTH CENTRAL MONTANA. WILL CONTINUE TO INCREASE CLOUDS OVERNIGHT WEST AND SOUTH CENTRAL. EXPECTATIONS ARE ISOLATED CONVECTION WILL BE CONFINED TO THE SOUTHWEST ZONES OVERNIGHT AND DRY CONDITIONS ELSEWHERE. UPDATE ISSUED AT 624 PM CDT TUE JUN 18 2013 LATEST WATER VAPOR IMAGERY THIS EVENING SHOWS A MID/UPPER LEVEL DISTURBANCE ROTATING THROUGH CENTRAL NORTH DAKOTA AT THIS TIME. VISIBLE SATELLITE IMAGERY AND SURFACE OBS SHOW SCT MID LEVEL CLOUDS STRETCHING FROM ROSEGLEN TO NEAR DICKINSON...WITH A SCT FAIR WEATHER CUMULUS FIELD ACROSS SOUTH CENTRAL AND EAST CENTRAL NORTH DAKOTA. WITH A H7-H5 RIDGE AXIS ANCHORED FROM WILLISTON TO BISMARCK AND INTO SIOUX FALLS SOUTH DAKOTA TONIGHT...EXPECT A DRY NIGHT ALONG AND EAST OF THE AFOREMENTIONED RIDGE AXIS. ATTENTION THIS EVENING AND OVERNIGHT TURNS TO AN UPSTREAM SHORTWAVE OVER SOUTHEAST WYOMING. THIS IS GENERATING THUNDERSTORMS IN THE HIGHER TERRAIN OF WYOMING...WITH A LARGE MID/HIGH LEVEL CLOUD CANOPY EXPANDING OVER EASTERN WYOMING AND SOUTHEAST MONTANA. THIS IS MOVING NORTHEAST AND WILL SLIDE INTO OUR SOUTHWEST ZONES THIS EVENING. THE LATEST RAP ADVECTS SOME LIGHT PRECIPITATION INTO THE FAR SOUTHWEST ZONES TOWARD 06Z. THE 18Z GFS IS MORE ROBUST IN GENERATING A LARGER SWATH OF LIGHT PRECIPITATION LATE TONIGHT THROUGH MID MORNING WEDNESDAY IN SOUTHWEST NORTH DAKOTA AND JUST GRAZING OUR SOUTH CENTRAL ZONES. HOWEVER OTHER MODELS DELAY THE SHOWERS/THUNDERSTORMS WITH THIS SHORTWAVE UNTIL WEDNESDAY AFTERNOON AND EVENING. WILL AWAIT THE 00Z DATA BEFORE MAKING ANY CHANGES BEYOND TONIGHT. WILL ALSO MONITOR THE CONVECTION APPROACHING THE SOUTHWEST THIS EVENING/OVERNIGHT. ONLY UPDATES THIS EVENING WAS TO HOURLY OBS AND TO INCREASE SKY GRID TRENDS IN THE SOUTHWEST AS MENTIONED ABOVE. THE CLOUD DEBRIS MAY MAKE IT INTO SOUTH CENTRAL NORTH DAKOTA BEFORE SUNRISE WEDNESDAY. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 324 PM CDT TUE JUN 18 2013 SURFACE TROUGH AND ASSOCIATED WARM FRONTAL BOUNDARY IN EASTERN MONTANA WILL BE THE FOCUS FOR SCATTERED THUNDERSTORMS LATE TONIGHT AND WEDNESDAY AFTERNOON. ANTICIPATE SOME THUNDERSTORMS WILL FIRE OVER THE HIGHER ELEVATION AREAS IN WYOMING/MONTANA/SOUTH DAKOTA AND DRIFT INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT. ON WEDNESDAY ONE LIMITING FACTOR WILL BE A SLOWING EVOLVING ELEVATED MIXED LAYER THAT MAY CAP THUNDERSTORMS OVER WESTERN NORTH DAKOTA WEDNESDAY AFTERNOON. HOWEVER BELIEVE THE INCREASING LOW LEVEL JET AND SIGNIFICANT CAPE VALUES JUSTIFY SCATTERED THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA WEDNESDAY AFTERNOON. WINDS ON WEDNESDAY SHOULD APPROACH BUT REMAIN BELOW WIND ADVISORY CRITERIA SOUTHWEST...PROBABLY 20 TO 35 MPH. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 324 PM CDT TUE JUN 18 2013 THE MAIN FORECAST ISSUE THROUGH THE LONG TERM PERIOD IS CONVECTIVE TRENDS AND POTENTIAL FOR PERIODS OF STRONG TO SEVERE STORMS...SOME ACCOMPANIED BY HEAVY RAINFALL. THE RUNS OF THE GFS/ECMWF ARE IN GENERAL AGREEMENT WITH A SLOWER PROGRESSION OF A LARGE CLOSED UPPER LOW IN THE PACIFIC NORTHWEST EARLY IN THE PERIOD...WITH THE NAM FASTEST IN BRINGING THE MAIN SYNOPTIC FEATURES EASTWARD. HAVE FAVORED THE GFS/EC SOLUTIONS FOR POPS WEDNESDAY NIGHT AND THURSDAY. THERE IS SOME POTENTIAL FOR AN MCS TO CLIP NORTHWEST COUNTIES LATE WEDNESDAY NIGHT INTO THURSDAY MORNING...FUELED BY A 40-50 KT LOW LEVEL JET. THE MAIN DECISION-MAKING ELEMENT WAS WHEN/WHERE THE STRONG MID-LEVEL CAP WOULD INHIBIT CONVECTION...BECAUSE OTHERWISE PLENTY OF CAPE AND SHEARING FOR SEVERE THUNDERSTORMS. WEDNESDAY EVENING THE AXIS OF THE MID-LEVEL CAP OF 10-14C IS SITUATED OVER WYOMING/EASTERN MONTANA AND NUDGING INTO SOUTH DAKOTA AND FAR SOUTHWESTERN NORTH DAKOTA. THE CAP BUILDS DURING THE EVENING NORTHWARD AND EASTWARD ACROSS THE DAKOTAS. AT THIS TIME IT APPEARS THE BEST CHANCE OF SEVERE THUNDERSTORMS BEGINS IN FAR WESTERN NORTH DAKOTA LATE EVENING WEDNESDAY OR EARLY MORNING THURSDAY...WITH SEVERE THUNDERSTORMS POSSIBLE. THE STORMS MOVE EASTWARD INTO CENTRAL NORTH DAKOTA BETWEEN MIDNIGHT AND DAYBREAK THURSDAY MORNING. THURSDAY THE ACCOMPANYING SURFACE FRONT IS PROGGED TO BE ORIENTED NORTH-SOUTH ACROSS CENTRAL NORTH DAKOTA...WITH THE BEST CHANCES OF THUNDERSTORMS IN NORTHWEST AND CENTRAL NORTH DAKOTA THURSDAY MORNING...AND SHIFTING TO CENTRAL NORTH DAKOTA THURSDAY AFTERNOON AND INTO THURSDAY EVENING. THE BEST CHANCE FOR SEVERE WEATHER THURSDAY IS IN THE NORTHWEST AND CENTRAL. FRIDAY AND FRIDAY NIGHT LOOKS TO BE THE TIME FRAME FOR WIDESPREAD MODERATE TO HEAVY RAINFALL. CONTINUED UPPER LEVEL ENERGY AND LOW LEVEL MOISTURE WITH A SURFACE LOW BECOMING ESTABLISHED OVER THE CENTRAL PLAINS AND OVERRUNNING PRECIPITATION NORTH OF THE LOW IS FAVORED FOR THE HEAVIEST RAINFALL. WIDESPREAD RAINFALL AMOUNTS OF 1 TO 2 INCHES IS POSSIBLE. THE MODELS CONTINUE TO DEPICT THE UPPER LEVEL LOW MAINTAINING ITS PRESENCE OVER THE ROCKIES WITH SOUTHWEST FLOW OVER NORTH DAKOTA WITH MULTIPLE UPPER LEVEL ENERGY IMPULSES MOVING ACROSS THE STATE IN THE UPPER FLOW. THE MODELS BRING THE UPPER LOW ACROSS THE STATE SUNDAY. PRECIPITATION CHANCES LESSEN MONDAY AND TUESDAY...BUT ZONAL FLOW ALOFT WOULD ALLOW SOME UPPER LEVEL IMPULSES TO SUPPORT SHOWERS AND THUNDERSHOWERS INTO EARLY NEXT WEEK. TEMPERATURES ARE EXPECTED TO BE SEASONABLE THROUGH THE PERIOD...WITH HIGHS IN THE 70S/LOWER 80S...AND LOWS GENERALLY IN THE 50S AND 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1230 AM CDT WED JUN 19 2013 VFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE TAF PERIOD. THERE WILL BE INCREASING MID AND HIGH CLOUDS EARLY THIS MORNING...WITH SCATTERED CUMULUS POSSIBLE DURING THE DAY WEDNESDAY. THERE IS A CHANCE OF THUNDERSTORMS DURING THE LATE AFTERNOON INTO THE EVENING WEDNESDAY AS A WARM FRONT BEGINS TO APPROACH THE REGION. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CK SHORT TERM...WAA LONG TERM...JV AVIATION...CK
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
400 AM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE CRUISES WEDNESDAY AND THURSDAY...BEFORE DROPPING ANCHOR IN THE WESTERN ATLANTIC TO BEGIN THE SUMMER SEASON. HIGH RIDGE ALOFT KEEPS DRY CONDITIONS THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AT 06Z SFC OBS INDICATE SECONDARY FRONT LOCATED ROUGHLY FROM HTS EAST/NORTHEAST TO NEAR CKB. NEAR AND AHEAD OF IT A FEW SHOWERS AND EVEN ONE THUNDERSTORM HAD REDEVELOPED EARLY THIS MORNING. THE ENHANCEMENT LIKELY DUE TO A VORT MAX...EVIDENT IN WV IMAGERY...MOVING QUICKLY ACROSS NORTH CENTRAL OHIO. ALL IN ALL EXPECT A NICE DAY FOR MOST FOLKS AS THE AFOREMENTIONED FRONT MOVES THROUGH THE AREA...UNDER PARTLY TO MOSTLY SUNNY SKIES BY THE AFTERNOON AND SEASONABLY WARM TEMPS. LARGE SCALE FORCING FOR SUBSIDENCE WILL OVERSPREAD THE FORECAST AREA FROM NW TO SE AS A 500MB S/W TROUGH PUSHES EASTWARD ACROSS AND EXITS TO THE EAST AROUND THE 18Z-21Z TIME FRAME. BY THE AFTERNOON HOURS HOWEVER...THE SFC FRONT BEGINS TO WASH OUT AND AS SFC HIGH PRESSURE REBUILDS TO THE EAST. MODELS IN GOOD AGREEMENT WITH GOOD SFC CONVERGENCE ALONG THE EASTERN HIGH TERRAIN PEAKS AS SFC FLOW ON THE EAST SIDE RETURNS QUICKLY TO THE EAST/SOUTHEAST...WHILE FLOW ON THE WINDWARD SIDE REMAINS NORTH/NORTHWEST. SOME QUESTION AND DOUBT AS TO THE DEPTH OF MOISTURE BEING DEPICTED ON LATEST NAM12 SOUNDINGS HOWEVER...AND LATEST RUC13 SOUNDINGS ARE INDEED MUCH DRYER IN LOWER LEVELS. EVEN WITH THE MORE SATURATED NAM12...PWATS STILL ONLY PROGGED AROUND 0.8IN-0.9IN WITH VERY DRY AIR ALOFT WHICH WOULD SERVE TO LIMIT COVERAGE. PREV FCST HAD A GOOD HANDLE ON THIS AND WILL CONTINUE SLIGHT CHANCE TO LOW CHANCE POPS ESSENTIALLY FROM THE HIGHEST PEAKS AND POINTS SOUTH AND EAST...WITH STORM MOTION TO THE SOUTHEAST. DID INSERT A SLIGHT THUNDER MENTION WITH DECENT INSTABILITY IN THAT AREA. AS SUCH...KEPT CLOUD COVER HIGHER IN THE EASTERN HIGH COUNTRY AS WELL. ALSO NUDGED MAX TEMPS UP AN ADDITIONAL DEGREE OR TWO FOR MOST LOCATIONS PER LATEST PROGGED 925MB AND 850MB TEMPS WITH MOS GUIDANCE SUPPORTING...ALTHOUGH DID KEEP MAX TEMPS IN THE MOUNTAINS JUST A BIT LOWER WITH MORE CLOUDS AND SOME AFTERNOON PRECIP POTENTIAL. OVERNIGHT FORECAST REMAINS VIRTUALLY UNCHANGED FROM PREV SHIFT THINKING...WITH MINS IN THE MID AND UPPER 50S LOWLANDS. WILL HAVE PRECIP ENDING AT 00Z THU IN THE MOUNTAINS. AREAS OF FOG ARE A GOOD BET ONCE AGAIN IN THE LOWLANDS UNDER A MOSTLY CLEAR SKY AND NEAR-CALM WINDS...ALTHOUGH SOME LOWER DEWPOINTS ACROSS SE OHIO AND MORE CLOUD COVER IN THE MOUNTAINS MAY LIMIT COVERAGE IN THOSE AREAS. && .SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/... SFC HIGH PRESSURE MOVE OFF SHORE THE NORTHEAST COAST LATE THURSDAY LOSING ITS INFLUENCE WEST OF THE APPALACHIANS. HOWEVER...ABUNDANT LOW LEVEL MOISTURE AND ELEVATED HEAT SOURCES COULD PRODUCE ISOLATED AFTERNOON SHOWERS OR STORMS OVER HIGHER ELEVATIONS THROUGH THE WEEKEND. A MID LEVEL RIDGE MOVES OVERHEAD SATURDAY PROVIDING SOME SUBSIDENCE AND CLEAR SKIES. AFTERNOON CU WILL BE COMMON JUST TO DISSIPATE AFTER SUNSET. && .LONG TERM /SUNDAY THROUGH TUESDAY/... RIDGING WILL CONTINUE TO STRENGTHEN THROUGH THE WEEKEND INCREASING HIGH TEMPERATURES INTO AT LEAST THE THE UPPER 80S. WITH A CONTINUED MOISTURE TAP DEW POINTS WILL ALSO INCREASE INTO THE UPPER 60S TO AROUND 70. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM WILL BE A POSSIBILITY MOST EVERY AFTERNOON AND EVENING. ABOVE NORMAL TEMPERATURES AND MUGGY CONDITIONS LOOK LIKELY TO CONTINUE INTO THE FIRST HALF OF NEXT WEEK AS THE BROAD UPPER LEVEL RIDGING OVER THE EASTERN HALF OF THE US CONTINUES. WILL BE LOOKING FOR A DRIER PATTERN TO SETTLE IN THRU LATE WEEK AND AT LEAST FIRST HALF OF WEEKEND. EXCEPTION IS THE MTNS WHERE A FEW SHRA/TSRA POSSIBLE EACH AFTN AS A LEE SIDE TROF SETS UP IN CONJUNCTION WITH LLVL SE FLOW AND DIFF HEATING. A S/W TROF WILL TRY TO BEAT DOWN UPR RIDGE JUST AS IT TRIES TO BUILD E INTO AREA LATE SUNDAY INTO MONDAY. HAVE CARRIED SOME CHC POPS WITH THIS AT THIS DISTANCE. TEMPS WARM UP TO 2 TO 4 DEGREES ABV NORMAL...ESPECIALLY AT NIGHT AT THE MUGGIES BEGIN TO TAKE OVER. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... A FEW SHOWERS HAVE REDEVELOPED LATE THIS EVENING AHEAD OF AN ADVANCING COLD FRONT...ROUGHLY FROM CKB TO HTS. AT THIS POINT...ALL SHRA HAS REMAINED JUST OFF TO THE NE OF CRW AND ONLY EXPECTED TO POTENTIALLY AFFECT EKN AND CKB. THESE SHOWERS WILL DELAY THE ONSET OF FOG AND LOW STRATUS...BUT WILL ONLY INCREASE DENSITY SHOULD A SHOWER MAKE A DIRECT IMPACT ON A TERMINAL ONCE THE SHOWER AND CLOUDS SCATTER. BY NEAR DAWN...EXPECT ALL SITES TO BE AT LEAST IFR IN REDUCED VIS...IF NOT LOWER. ALL OF THIS LOW LEVEL MOISTURE WILL BE SLOW TO BURN OFF WED MORNING DESPITE FRONTAL PASSAGE AS IT MIXES INTO MORNING CU. BY MID-MORNING VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR THE REMAINDER OF THE DAY AND EARLY EVENING AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE NORTH...ALTHOUGH A LATE DAY SHOWER OR THUNDERSTORMS MAY POP UP OVER THE HIGHER TERRAIN. MVFR VIS MAY REDEVELOP NEAR END OF PERIOD. NEAR CALM WINDS OVERNIGHT...AND BECOME LIGHT N TO NE ON WED. FLOW ALOFT WILL BE MAINLY LIGHT N. CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE...MEDIUM. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY... FORECAST CONFIDENCE: STRATUS MAY MATERIALIZE MORE THAN FCST WHICH WOULD ALLOW FOR LESS LIFR FG TO DEVELOP ACROSS THE AREA OVERNIGHT. THE TIMING OF IMPROVEMENT WED MORNING COULD ALSO VARY FROM FCST. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE WED 06/19/13 UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19 EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15 CRW CONSISTENCY L L L L L L M M H H H H HTS CONSISTENCY L L L L L L M H H H H H BKW CONSISTENCY L L L L L L M M M H H H EKN CONSISTENCY L L L L L L M M M H H H PKB CONSISTENCY L L L L L L M H H H H H CKB CONSISTENCY L L L L L M M M H H H H AFTER 06Z THURSDAY... IFR OR WORSE FG DEVELOPING WED NT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/50 NEAR TERM...50 SHORT TERM...ARJ LONG TERM...JR AVIATION...50
AREA FORECAST DISCUSSION
NWS NORMAN OK
347 AM CDT WED JUN 19 2013 .DISCUSSION... CURRENTLY...A WEAK MCS CONTINUES TO MOVE EASTWARD ACROSS SRN KS AND NWRN OK. THIS AREA OF CONVECTION REMAINS FOCUSED ALONG A LOW- LEVEL MOISTURE/THETA E AXIS POSITIONED ALONG/NEAR THE WRN KS/OK BORDER. OVERALL...MESOSCALE GUIDANCE HAS HAD A DIFFICULT GO THIS MORNING IN THE TRACK AND INTENSITY OF THESE STORMS. CURRENT THOUGHTS LEAN TOWARD THE MCS WEAKENING OVER THE NEXT FEW HOURS AS IT CONTINUES TO TRACK EASTWARD. CONDITIONS ARE LESS FAVORABLE FOR MCS MAINTENANCE ACROSS NRN AND CENTRAL OK...WHERE THE MOISTURE PROFILE IS LESS FAVORABLE AND MID-LEVEL LAPSE RATES WEAKEN CONSIDERABLY. THERE IS DECENT DEEP LAYER SHEAR...30-40KTS SPREAD INTO CENTRAL OK...BUT MUCAPES REMAIN LOW FOR MCS SUPPORT...700 TO 1000 J/KG. OVERALL...THE NEXT 12 TO 24 HOURS WILL POSE A FAIRLY DECENT CHALLENGE FORECASTWISE. THE RECENT 06Z RUN OF THE HRRR REVISES ITS PREVIOUS FORECAST...WITH CONVECTION DEVELOPING BEHIND THE MAIN LINE AND SURGING SOUTHWARD THROUGH THE TX PANHANDLE THROUGH THE MORNING. CURRENT RADAR TRENDS SUGGEST THIS MIGHT BE A POSSIBLE SCENARIO...AS NEW CONVECTION HAS STARTED TO DEVELOP OVER THE PAST HOUR...SINCE 230 AM...ACROSS SERN CO AND THE OK PANHANDLE. FOR THE MOMENT...WILL CONTINUE WITH CHANCE POPS ACROSS NWRN OK THROUGH THE MORNING HOURS. FOR THIS AFTERNOON...THE SHALLOW 500MB RIDGE WILL CONTINUE TO SHIFT/TILT EASTWARD ACROSS THE SRN PLAINS...WHILE ANOTHER LOW AMPLITUDE SHORTWAVE TRAVERSES THE REGION. WITH UPPER LEVEL SUPPORT...AND THE PAC NW TROUGH DIGGING EASTWARD...A STOUT SFC TROUGH/FRONT WILL EXTEND THE LENGTH OF THE FRONT RANGE INTO THE CENTRAL HIGH PLAINS. THIS COULD RESULT IN SOME WEAK SCATTERED CONVECTION LATER THIS AFTERNOON AND OVERNIGHT ACROSS NRN OK...PRIMARILY WELL NORTH OF THE I-40 AND I-44 CORRIDORS. EXPECT COVERAGE TO BE LIMITED WITH THIS SYSTEM...WITH MOST LOCATIONS LIKELY REMAINING DRY AFTER THIS MORNING. FOR THE REMAINDER OF THE WEEK...UPPER LEVEL RIDGING WILL TAKE HOLD...WITH SOUTH/SOUTHWEST FLOW SETTING UP SLOWLY THROUGH THE WEEKEND. TEMPERATURES WILL WARM BACK UP...WITH AFTERNOON HIGHS WELL INTO THE 90S...APPROACHING THE 100S ACROSS SWRN OK AND WRN N TX. THERE COULD BE A FEW ISOLATED SHOWERS ACROSS FAR NWRN OK SUNDAY AS THE WRN TROUGH INTENSIFIES AND A SFC FRONT APPROACHES THE REGION...BUT AT THE MOMENT...EXPECT THE GOOD MAJORITY OF THE AREA TO REMAIN DRY THROUGH THE WEEKEND. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 85 69 89 71 / 10 10 10 0 HOBART OK 90 70 96 72 / 20 10 10 10 WICHITA FALLS TX 90 72 95 73 / 10 10 0 0 GAGE OK 87 69 96 73 / 50 20 10 10 PONCA CITY OK 85 69 88 72 / 10 30 30 10 DURANT OK 88 71 91 72 / 10 10 10 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 11/04
AREA FORECAST DISCUSSION
NWS TULSA OK
303 AM CDT WED JUN 19 2013 .DISCUSSION... A RIDGE OF HIGH PRESSURE ALOFT WILL BEGIN TO NUDGE INTO THE AREA FROM THE SOUTHWEST TODAY. BEFORE WE GET INTO SOMETHING OF A DRY PERIOD...THE AREA WILL HAVE TO CONTEND WITH A COUPLE OF THUNDERSTORM COMPLEXES. THIS MORNING THERE IS THUNDERSTORM COMPLEX THAT EXTENDS FROM SOUTHWEST KANSAS INTO THE TEXAS PANHANDLE. THE LATEST HRRR SHOWS THIS COMPLEX MOVING INTO CENTRAL OKLAHOMA THIS MORNING AS IT DECAYS. HAVE LEFT POPS OUT OF THE FORECAST FOR TODAY BUT NOT FEELING OVERLY CONFIDENT ABOUT THIS DECISION. COULD SEE SOME REDEVELOPMENT ON THE OUTFLOW BOUNDARY CREATED BY THIS COMPLEX THIS AFTERNOON. ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP ACROSS WESTERN KANSAS AGAIN THIS AFTERNOON/EVENING AND MAKE A RUN AT NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS LATE TONIGHT INTO THURSDAY. DO HAVE POPS IN THE FORECAST TO ACCOUNT FOR THIS FEATURE AS THE MODELS HAVE BEEN CONSISTENTLY SHOWING THIS FOR SEVERAL RUNS. THE UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE AREA THROUGH THE WEEKEND. THERE ARE SOME SIGNS THAT THERE MAY BE ENOUGH WEAKNESS IN THE RIDGE THAT SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE SATURDAY AND SUNDAY AFTERNOONS IN THE FAVORED TERRAIN AREAS OF SOUTHEAST OKLAHOMA INTO NORTHWEST ARKANSAS. && .PRELIMINARY POINT TEMPS/POPS... TUL 90 71 90 74 / 10 10 20 10 FSM 90 68 92 71 / 10 10 10 0 MLC 89 70 91 73 / 0 0 10 10 BVO 88 69 88 72 / 10 20 30 10 FYV 86 64 87 68 / 10 10 10 0 BYV 87 65 88 68 / 10 10 10 10 MKO 88 69 89 72 / 10 10 20 10 MIO 89 68 88 71 / 10 20 30 10 F10 88 70 90 73 / 10 10 10 10 HHW 89 70 92 72 / 0 0 10 10 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...12 LONG TERM....10
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
155 AM EDT WED JUN 19 2013 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION ON WEDNESDAY...BUT WITHOUT ENOUGH MOISTURE TO EXPECT MORE THAN ISOLATED SHOWERS. MOIST EASTERLY FLOW WILL THEN KEEP SOME RAIN CHANCES THRU LATE WEEK MAINLY OVER THE MOUNTAINS. HIGH PRESSURE WILL BUILD OVER THE AREA FOR THE WEEKEND...MAINTAINING A WARM AND MOIST AIRMASS WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH AFTERNOON. && .NEAR TERM /THROUGH TODAY/... 930 PM UPDATE...DUE TO LARGELY BOUNDARY-PARALLEL SHEAR...CELLS THAT INITIALLY FORMED AROUND SUNSET HAVE TRAINED ROUGHLY ALONG A GREENVILLE TO CHESTER LINE IN CONVERGENT ZONE NEAR THE FRONT. ACTIVITY NOW BEGINNING TO DIMINISH AS INSTABILITY WANES...BUT SOME PRECIP LIKELY TO CONTINUE FOR ANOTHER HOUR OR SO AT LEAST. HOWEVER WITH OUTFLOW PUSHING OUT ACRS GREENVILLE AND SPARTANBURG COUNTIES CAN/T RULE OUT A COUPLE OF ISOLATED SHOWERS FIRING FROM THE SRN PORTIONS OF THOSE COUNTIES SOUTH. NORTH OF THE CURRENT ACTIVITY PRECIP CHANCES ARE TOO SMALL TO MENTION THIS EVENING. STORMS ALONG THE UPSTREAM BOUNDARY OVER KY WOULD TAKE UNTIL AFTER MIDNIGHT TO REACH THE TN/NC BORDER...BUT THEY ARE ALREADY STRUGGLING IN THE MORE STABLE ENVIRONMENT THEY ARE ENTERING...SO DO NOT SEE A NEED TO REFLECT THESE STORMS IN POPS TONIGHT. TEMPS HAVE BEEN ON TRACK SO FAR THIS EVENING AND WILL MAINTAIN GOING LOWS. 730 PM UPDATE...PRECIP ACTIVITY NOW CONFINED TO THE PIEDMONT SHOULD CONTINUE TO MOVE OUT OF THE CWFA WITH FRONT PUSHING INTO THAT AREA. ACTIVITY GENERALLY WEAKENING WITH LOSS OF HEATING ANYWAY. RAP AS WELL AS LOCAL WRF MODEL DO NOT SHOW ANY FURTHER DEVELOPMENT THIS EVENING...AND WINDS ARE DRY AND DOWNSLOPING ANYWAY. STILL DO THINK SOME OF THE REMAINING CU IN EAST TN AND THE MTNS OF WNC WILL REMAIN AS PATCHY STRATUS FOR MUCH OF THE NIGHT...WITH CONVECTIVE DEBRIS SPREADING ACROSS THE SE HALF OF THE CWFA TOO. KEPT PCLDY-MCLDY SKIES OVERNIGHT AS A RESULT. AS OF 230 PM EDT TUESDAY...A BIT OF A TRICKY FCST THIS AFTERNOON AND EARLY EVENING. THE OVERALL PATTERN IS WELL AGREED UPON BY THE MODELS...HOWEVER CONFIDENCE IN THE EVOLUTION OF S/W ENERGY ACROSS THE CWFA IS NOT VERY HIGH DUE TO MODEL DIFFERENCES. THE LATEST RADAR SHOWS AN UNSTABLE AIRMASS TO THE WEST BECOMING INCREASINGLY UNSTABLE INTO THE WRN ZONES. VSBY SAY SHOW GOOD CLEARING AND HEATING TAKING PLACE...BUT IN A DEEPLY MOIST ATMOS SBCAPE VALUES WILL LIKELY REACH ONLY MOD LEVELS. THIS IS A LITTLE EVIDENT IN THE LOW TOP CONV SEEN TO THE WEST. IN ANY REGARD...WILL ANTICIPATE TSTMS DEVELOPING AHEAD OF THE WEAK COLD FRONT AND DEPENDING ON THE STRENGTH OF THE CROSS S/W ENERGY...SOME OF THESE COULD BECOME STRONG TO SEVERE THIS AFTERNOON. THE MAIN THREAT WOULD BE LARGE HAIL AND PERHAPS DAMAGING WINDS AS DRIER AIR WORKS INTO THE MLVLS. EXPECT A WIND SHIFT ACROSS THE MTNS AROUND 00Z AND INTO THE UPSTATE NEAR 05Z. THIS WILL SUPPRESS ANY ACTIVITY TO THE SOUTH WITH A LOWER THETA/E AIRMASS MIXING IN. SOME PATCHY DENSE FG IS POSSIBLE AROUND DAYBREAK IN THE MTN VALLEYS AS THE PGRAD IS NOT REAL TIGHT BEHIND THE FRONT AND BROADENS THROUGH 12Z. A CP HIGH WILL WORK SOUTH INTO THE OH VALLEY TOMORROW AND PUSH A BACKDOOR COLD FRONT INTO THE NRN ZONES BY THE AFTERNOON. THERE IS NOT MUCH MOISTURE AVAILABLE WITH THIS SYSTEM SO WILL EXPECT THE BEST PRECIP CHANCES ACROSS THE MTNS...WHERE AN E/LY UPSLOPE FLOW BRINGS IN ATL MOISTURE. POPS HAVE BEEN HELD TO SLIGHT/CHANCE ACROSS THE MTNS AND SLIGHT ELSEWHERE...WITH MAINLY -SHRA AND PERHAPS A MODERATE THUNDERSTORM OR TWO ACROSS THE FHILLS AND MTNS. MAX TEMPS SHOULD STILL BE A COUPLE DEGREES BELOW NORMAL WITH THE NE/LY SFC FLOW AND AIRMASS MIXING. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... AS OF 200 PM EDT TUESDAY...THE SHORT TERM WILL BE DOMINATED BY SURFACE HIGH PRESSURE THAT WILL SET UP CAMP OFF THE NEW ENGLAND COAST WHICH WILL REMAIN RIDGED SWD INTO THE SOUTHERN APPALACHIANS THROUGH FRI. THE UPPER AIR PATTERN WILL BE ALMOST INDETERMINATE IN THE DEEP SOUTH WITH VERY WEAK FLOW. THE AREA WILL BE BETWEEN A TROUGH WELL TO THE NE AND AN UPPER RIDGE OVER THE SOUTHERN PLAINS. HENCE...NO SIGNIFCANT UPPER FORCING IS ANTICIPATED. MODEL TIME HEIGHTS INDICATE THAT MOISTURE WILL REMAIN RELATIVELY HIGH IN THE BOUNDARY LAYER WITH DRYING ESSENTAILLY ABOVE 10KFT THROUGH THU NIGHT. HOWEVER...MOISTURE IN THE COLUMN IS FORECAST TO DECREASE ON FRI. HENCE...THE WEATHER SHOULD BE DRIVEN BY MAINLY BY THE LOW LEVEL WIND FLOW AND ANY MECHANICAL LIFT IT MUSTERS...PLUS DIURNAL HEATING. THEREFORE...MAINLY DIURNAL/SCATTERED CONVECTION IS EXPECTED PRIMARILY OVER THE MOUNTAINS...WITH PERHAPS A DOWN TICK IN COVERAGE ON FRI AFTERNOON DUE TO THE DRYER AIR. WITH THE WEAK UPSLOPE FLOW...SOME NOCTURNAL WIDELY SCATTERED SHOWERS WILL REMAIN POSSIBLE OVER THE MOUNTAINS WED/THU NIGHTS. USED AN ALLBLEND APPROACH TO TEMPERATURES WHICH PRODUCED MAX TEMPS ON THU AND FRI ABOUT A CATEGORY BELOW AVERAGE. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 2 PM TUESDAY...THE MAIN FEATURE FOR THE EXTENDED PERIOD IS A RIDGE OF HIGH PRESSURE THAT WILL SET UP OVER THE SOUTHEASTERN CONUS OVER THE WEEKEND AND INTO MONDAY. THE BERMUDA HIGH WILL REMAIN SITUATED OVER THE ATLANTIC OFF THE EAST COAST...SETTING UP A MOIST SOUTHEASTERLY TO SOUTHWESTERLY LOW-LEVEL FLOW REGIME FOR THE REGION. THIS WILL DRIVE MAINLY DIURNAL CONVECTION FOR THE PERIOD...WITH GREATER CHANCE POPS FAVORING THE HIGHER ELEVATIONS EACH AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK. THE PERSISTENT RIDGE WILL ALLOW FOR A SLIGHT WARMING TREND...WITH TEMPS NEAR TO SLIGHTLY ABOVE AVERAGE BY THE END OF THE EXTENDED PERIOD. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... AT KCLT...BORDERLINE MVFR TO VFR CONDITIONS ARE EXPECTED DURING THE OVERNIGHT HOURS AS A MOIST BOUNDARY LAYER WILL AID IN LOW STATUS PERSISTENCE...AND ALSO PROMPT POSSIBLE MVFR CONDITIONS FOR FOG DURING THE MID TO LATE MORNING HOURS. OTHERWISE...NORTHERLY WINDS WILL PERSIST THROUGH THE MORNING BEFORE SHIFTING SOMEWHAT EASTERLY BY AFTERNOON. CONDITIONS WILL IMPROVE DURING THE LATE MORNING TO AFTERNOON HOURS ON WEDNESDAY AS DRIER AIR ADVECTS IN FROM THE NORTH. HOWEVER...LOOK FOR SOME BKN TO SCT LOW/MID LEVEL CLOUDS TO PERSIST THROUGH THE PERIOD. KEPT ANY MENTION OF TSRA OUT OF THE TAF AS ANY INSTABILITY SHOULD REMAIN CAPPED OFF. ELSEWHERE...ALTHOUGH CIGS SHOULD GENERALLY REMAIN ABOVE 3KFT AT ALL SC SITES...SOME BRIEF LOWERING TO HIGH END MVFR LEVELS CANNOT BE RULED OUT AS CONVECTIVE DEBRIS REMAINS SCATTERED ACROSS A MOIST BOUNDARY LAYER. KEPT MENTION OF MVFR FOG AT ALL SITES THROUGH MID TO LATE MORNING DUE TO AMPLE LOW LEVEL MOISTURE AND CALMING NORTHERLY WINDS. OTHERWISE...CONDITIONS SHOULD IMPROVE TO VFR AT ALL SC SITES BEYOND WEDNESDAY MORNING. AS FOR THE NC SITES...WENT WITH PROB30 AT KAVL AND KHKY AS SHORT TERM CONVECTION ALLOWING GUIDANCE INDICATES SOME UPDRAFTS BEING ABLE TO OVERCOME THE CAP WITH THE AID OF MECHANICAL FORCING. BEYOND THAT...SOME LOW/MID LEVEL VFR CIGS ARE LIKELY AT THE NC SITES...WHILE FULL VFR MID/HIGH CLOUDS WILL PERSIST AT THE SC SITES THROUGH THE PERIOD. OUTLOOK...MOIST EASTERLY FLOW WILL SET UP WED NIGHT LEADING TO LOW STRATUS ACROSS MUCH OF THE AREA THU MORNING WITH RESTRICTIONS LIKELY. CONFIDENCE TABLE... 06-12Z 12-18Z 18-24Z 00-06Z KCLT HIGH 91% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 82% HIGH 94% HIGH 100% HIGH 100% KAVL HIGH 83% HIGH 99% HIGH 100% HIGH 100% KHKY MED 74% HIGH 94% HIGH 100% HIGH 100% KGMU MED 75% HIGH 92% HIGH 100% HIGH 100% KAND MED 74% HIGH 97% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...WIMBERLEY NEAR TERM...SBK/WIMBERLEY SHORT TERM...LG LONG TERM...VISIN AVIATION...CDG
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1140 PM CDT TUE JUN 18 2013 .UPDATE... 06Z TAF DISCUSSION. && .AVIATION... RADAR SHOWS CONVECTION NEAR PAH MOVING SOUTHWARD AND NOT EXPECTED TO AFFECT ANY AIRPORTS OVERNIGHT. CALM WINDS AND MOSTLY CLEAR SKIES WILL LEAD TO PATCHY MVFR/IFR FOG AT ALL TERMINALS TOWARDS SUNRISE. IMPROVEMENT TO VFR BY 13-14Z WITH SCT CUMULUS AND LIGHT NORTHEAST WINDS ON WEDNESDAY. SHAMBURGER && .PREV DISCUSSION... /ISSUED 811 PM CDT TUE JUN 18 2013/ UPDATE... BROKEN LINE OF SHOWERS AND TSTMS ATTEMPTING TO MOVE SOUTHWARD THROUGH WESTERN KY AT THIS TIME. THE ACTIVITY IS STILL SEVERAL COUNTIES NORTH OF THE TN/KY LINE BUT IS MOVING SOUTH. LATEST LAPS DATA SHOWING THAT CAPES DROP FROM 1400 J/KG VCNTY OF STORMS NOW...TO NEAR 600 J/KG ALONG THE TN/KY LINE. 850 MB FLOW IS GENERALLY NORTHERLY WHICH DOES NOT USUALLY CONDONE NOCTURNAL CONVECTIVE SUPPORT. FURTHERMORE...UPPER DIFFLUENCE IS LOOKING MINIMAL. HRRR OF LITTLE SUPPORT AND ONLY GOES OUT TO 03Z FOR NOW. WILL OPT TO MAKE NO CHANGES TO THE FCST AND KEEP THE 20 POPS GOING. WILL REMOVE THOSE POPS IF AND WHEN THE CONVECTION TO THE NORTH COMPLETELY DIES OUT. PREV DISCUSSION... /ISSUED 622 PM CDT TUE JUN 18 2013/ AVIATION... NORTHWEST FLOW IN PLACE THIS EVENING. DISTURBANCE ACROSS SOUTHERN IN WILL ATTEMPT TO DROP SOUTHWARD OVERNIGHT. THIS FEATURE SHOULD WEAKEN BUT AN ISOLATED TSTM OR TWO COULD FLIRT WITH CROSSING THE TN/KY BORDER LATE TONIGHT. OTW...SOME LIGHT FOG POSSIBLE TOWARD 12Z. ANOTHER DRY DAY WITH PARTIAL SUNSHINE EXPECTED FOR YOUR WEDNESDAY. PREV DISCUSSION... /ISSUED 228 PM CDT TUE JUN 18 2013/ DISCUSSION... FRONTAL BOUNDARY AND ASSOCIATED CONVECTION NOW WELL SOUTH OF MID STATE WITH SKIES BECOMING PARTLY SUNNY OVER MUCH OF THE CWA AT MID-AFTERNOON. RATHER SHARP SHORT WAVE ACROSS EASTERN IOWA THIS AFTERNOON WILL WORK SOUTHEASTWARD ALONG FRONTAL BOUNDARY THAT CURRENTLY EXTENDS FROM CENTRAL ILLINOIS ACROSS INDIANA INTO OHIO. ALREADY BEGINNING TO SEE SOME CONVECTION FIRING ALONG THAT BOUNDARY. SURFACE BOUNDARY PROGGED TO SINK SOUTHWARD THIS EVENING PRECEDING BY CONVECTION. FRONT WILL BE UNDERGOING FRONTOLYSIS BY THE TIME IT GETS THIS FAR SOUTH. EVEN THOUGH THE FRONT WILL BE WEAKENING I DONT FEEL CONFORTABLE NOT HAVING AT LEAST A MENTION OF ISOLATED THUNDER IN THE FORECAST FOR THE EVENING PERIOD. THERE STILL COULD BE ISOLATED THUNDER ON THE UPPER CUMBERLAND FOR A COUPLE OF HOURS AFTER MIDNIGHT. ALSO...AM EXPECTING LATE NIGHT PATCHY FOG TO DEVELOP. ON WEDNESDAY ANOTHER SHORT WAVE DROPS SOUTHEAST THAT COULD DEVELOP ISOLATED THUNDER ESPECIALLY DURING THE AFTERNOON AND EARLY EVENING. THURSDAY THROUGH THE WEEKEND WILL TURN OUT QUITE SUMMER-LIKE... RIGHT ON CUE WITH THE SUMMER SOLSTICE WHICH OCCURS FRIDAY JUNE 21ST AT 12:04 AM CDT. PLAINS UPPER RIDGE WILL REMAIN IN PLACE INTO THE WEEKEND WITH MID STATE REMAINING IN NORTHWEST FLOW. THIS MEANS A THUNDERSTORM CHANCE PRETTY MUCH EACH DAY. BOYD && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
318 AM CDT WED JUN 19 2013 .DISCUSSION... THE ONLY MAJOR FORECASTING CHALLENGE WITH THIS PACKAGE WILL BE PATCHY FOG IN THE EASTERN ZONES THIS MORNING AND THUNDERSTORM CHANCES TODAY. LIGHT WIND AND DAMP GROUND ACROSS EAST TEXAS AND THE EASTERN PORTIONS OF NORTH TEXAS WILL RESULT IN PATCHY FOG THROUGH MID MORNING TODAY. IT APPEARS THAT MOST OF THE DENSE FOG SHOULD BE IN EAST TEXAS BUT A FEW NORTH TEXAS LOCATIONS MAY BRIEFLY FALL TO 1/2 MILE VISIBILITY. BY 11 AM...ANY FOG THAT DID DEVELOP WILL HAVE DISSIPATED. A COMPLEX OF STORMS...CURRENTLY ACROSS WESTERN OKLAHOMA AND THE PANHANDLE...WILL CONTINUE MOVING SOUTHEAST THROUGH THE EARLY MORNING HOURS. CLOUD TOPS IN THE SOUTHERN PORTION OF THE COMPLEX HAVE BEEN WARMING OVER THE PAST COUPLE OF HOURS AND THIS TREND WILL LIKELY CONTINUE. THE HRRR SEEMS TO HAVE THE MOST REASONABLE SOLUTION OF ALL MODELS BASED ON RADAR TRENDS OVER THE LAST FEW HOURS SO WILL FOLLOW IT FAIRLY CLOSELY. THEREFORE...EXPECT MOST OF THE WEST TEXAS ACTIVITY TO DISSIPATE BEFORE REACHING THE NORTHWEST ZONES AROUND MID MORNING...BUT WILL LEAVE 20 POPS IN TO ACCOUNT FOR ANY SHOWER OR STORM THAT MANAGES TO HOLD TOGETHER. BY THIS AFTERNOON...A FEW SHOWERS OR STORMS MAY DEVELOP ACROSS THE REGION AS TEMPERATURES WARM INTO THE 90S AND SOME LEFT OVER BOUNDARIES PROVIDE A FOCUS FOR LIFT. ANY STORMS THAT DO DEVELOP SHOULD BE DISORGANIZED PULSE STORMS DUE TO THE WEAK SHEARED AND WEAK FLOW ENVIRONMENT EXPECTED. ANY SHOWERS OR STORMS THAT DO DEVELOP THIS AFTERNOON WILL DISSIPATE WITH THE LOSS OF SURFACE HEATING AND INCREASING LARGE SCALE SUBSIDENCE FROM A BUILDING UPPER LEVEL RIDGE. THE UPPER RIDGE WILL BECOME THE DOMINANT WEATHER FEATURE ACROSS THE REGION THURSDAY THROUGH EARLY NEXT WEEK. THE GOOD NEWS IS THAT THE RIDGE WILL NEVER BECOME EXTREMELY STRONG AND AS A RESULT AFTERNOON HIGH TEMPERATURES SHOULD NOT BE TOO MUCH WARMER THAN SEASONAL NORMALS. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK GENERALLY IN THE LOWER AND MIDDLE 90S AND LOWS MOSTLY IN THE 70S. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 94 74 95 75 96 / 20 10 0 0 0 WACO, TX 94 72 94 73 95 / 10 10 0 0 0 PARIS, TX 91 70 92 71 94 / 20 10 5 0 5 DENTON, TX 94 71 95 72 96 / 20 10 0 0 0 MCKINNEY, TX 91 69 92 70 94 / 20 10 5 0 0 DALLAS, TX 94 75 94 76 96 / 20 10 0 0 0 TERRELL, TX 92 71 93 72 94 / 20 10 5 0 5 CORSICANA, TX 92 72 93 73 94 / 20 10 5 0 0 TEMPLE, TX 93 71 93 72 94 / 10 10 0 0 0 MINERAL WELLS, TX 93 70 94 70 96 / 20 5 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 91/79
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
104 AM EDT WED JUN 19 2013 .SYNOPSIS... A WEAK COLD FRONT WILL DRIFT SOUTH INTO THE AREA LATER TONIGHT AND WEDNESDAY BEFORE DISSIPATING ALONG THE BLUE RIDGE WEDNESDAY EVENING. WEAK HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE NORTH LATER WEDNESDAY NIGHT AND THURSDAY...RESULTING IN SOMEWHAT DRIER WEATHER INTO THE END OF THE WEEK. && .NEAR TERM /THROUGH TODAY/... AS OF 1015 PM EDT TUESDAY... THE COLD FRONT WAS WELL SOUTH OF THE FORECAST AREA AT 02Z/10PM. SATELLITE PICTURES SHOWED SCATTERED CLOUDS OVER THE FORECAST AREA. ENOUGH CLEARING AND HIGH ENOUGH DEW POINTS TO ADD MORE FOG TO THE FORECAST FOR TONIGHT. LATEST WRF AND RAP GUIDANCE SUGGESTED LOW LEVEL MOISTURE AND A CHANCE OF SHOWERS OVER SOUTHEAST WEST VIRGINIA OVERNIGHT AND IN THE VIRGINIA PIEDMONT EARLY WEDNESDAY MORNING. THE NEXT COLD FRONT OVER THE OHIO VALLEY WILL APPROACH THE FORECAST AREA AFTER MIDNIGHT. MODELS HAVE ONLY A LOW CHANCE OF PRECIPITATION WITH THIS FRONT. HAVE ALIGNED THE HIGHER PROBABILITY OF PRECIPITATION AHEAD OF THIS FRONT AND KEPT A LOW CHANCE IN THE PIEDMONT LATE TONIGHT. THE BROAD TROUGH ACROSS EAST COAST WILL SHIFT SLIGHTLY EASTWARD AS THE UPPER RIDGING BUILDS. IT WILL REMAIN WARM AND HUMID OVERNIGHT WITH LOW TEMPERATURES FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S IN THE SOUTHEAST. KEPT THE LIGHT POPS IN FOR WEDNESDAY WITH BEST CHANCES ACROSS THE SOUTH. PLAYED HIGHS WEDNESDAY CLOSER TO COOLER MOS VALUES FROM THE UPPER 60S IN THE WESTERN MOUNTAINS TO THE LOWER 80S IN THE PIEDMONT. && .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... AS OF 345 PM EDT TUESDAY... SUBSIDENCE AND DRYING ALOFT INCREASES FOR THE LATER HALF OF THE WEEK AS HIGH PRESSURE BUILDS INTO THE AREA FROM THE NORTH WEDNESDAY NIGHT AND THURSDAY...WITH A BROAD EASTERLY COMPONENT TO THE WIND AS THE HIGH DRIFTS TO ALONG THE COAST LATE THURSDAY INTO FRIDAY. WITH HEIGHTS BUILDING ALOFT...AND A DRY MID LEVEL EASTERLY WIND...LOOKING AT MAINLY TRANQUIL WEATHER WITH LITTLE OR NO PRECIP THREAT. TEMPERATURES WILL BE NEAR SEASONAL...NOT TOO HOT...NOT TOO COOL. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 345 PM EDT TUESDAY... MODERATING TEMPERATURES EXPECTED OVER THE WEEKEND AND INTO EARLY NEXT WEEK AS THE UPPER LEVEL RIDGE CONTINUES TO BUILD...850 TEMPS CREEPING TOWARD +2OC FOR MONDAY AND TUESDAY. THIS SUGGESTS SURFACE TEMPS WILL TOP OUT MAINLY IN THE 80SF...TESTING 90F DEGREES FOR THE URBAN AREAS. NO REAL FOCUS FOR DEEP CONVECTION DURING THE PERIOD EXCEPT FOR CONVERGENCE OVER THE MTNS...SO KEPT ANY PRECIP THREAT MAINLY DIURNAL AND PRIMARILY TARGETED TO THE MTNS. && .AVIATION /04Z WEDNESDAY THROUGH SUNDAY/... AS OF 1240 AM EDT WEDNESDAY... DEEPER MOISTURE HAS EXITED THE AREA TONIGHT AHEAD OF A WEAK SECONDARY COLD FRONT JUST NORTH OF REGION THAT WILL DRIFT SOUTH OVERNIGHT. FEW REMAINING SHRA AHEAD OF THE BOUNDARY LIKELY TO FADE UPON APPROACH FROM THE NORTH SO EXPECTING OVERALL LACK OF PRECIP THROUGH DAYBREAK. HOWEVER FLYING CONDITIONS IN THE WAKE OF THE HEAVIER RAINFALL FROM TUESDAY WILL DETERIORATE OVERNIGHT AS AREAS OF FOG/STRATUS DEVELOP IN THE VALLEYS AND OUT EAST ESPCLY AROUND KDAN. THIS SHOULD RESULT IN AREAS OF IFR/LIFR CIGS AND VSBYS IN FOG WITH KROA ONLY SEEING A PERIOD OF MVFR LATE. EXPECT LOW CONDITIONS TO GRADUALLY IMPROVE TO VFR WITH HEATING WED MORNING BEFORE THE FLOW SLOWLY TURNS MORE SE ALLOWING BKN 4-6K FT CU CIGS TO REDEVELOP ESPCLY ALONG THE BLUE RIDGE. EASTERN LOCATIONS SUCH AS KLYH/KDAN MAY SEE LOW CIGS/VSBYS HANG ON LONGER UNDER LIGHT NE FLOW. LATEST MODELS THEN SUGGEST SOME LATE DAY SHRA/TSRA POTENTIAL MAINLY KROA/KBCB SO INCLUDING A VCTS THERE. OTRW LEAVING OUT PRECIP MENTION GIVEN ISOLATED NATURE ELSW. LEFTOVER CLOUDS AND WIDELY SCATTERED CONVECTION MAY LINGER INTO WEDNESDAY NIGHT ALONG THE BLUE RIDGE CORRIDOR WITH MOST OF THIS COVERAGE LIKELY ENDING UP SOUTH OF THE TERMINALS BEFORE ENDING LATER WED NIGHT. ADDED FOG THEN LIKELY AFTER MIDNIGHT...MOSTLY BEYOND THE END OF THE VALID TAF PERIOD SO WONT INCLUDE MENTION. FOR THURSDAY INTO THE WEEKEND...CONTINUED DIURNAL CONVECTION...ESPECIALLY ALONG THE APPALACHIANS...WITH LOCALLY BRIEF MVFR-IFR CIGS/VSBYS IN TSRA. AREAS OF MVFR-IFR VSBYS BR...LOCALLY IFR FG...ALSO POSSIBLE DURING THE MORNING HOURS. OTRW OVERALL VFR DURING THE DAYTIME HOURS BEFORE/AFTER ANY RIDGE ORIENTED CONVECTION DEVELOPS. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...JH NEAR TERM...AMS/KK SHORT TERM...PM LONG TERM...PM AVIATION...JC/JH/KK
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1024 PM PDT Tue Jun 18 2013 .SYNOPSIS... A band of moderate rain will develop over the Idaho Panhandle and extreme eastern Washington and continue on Wednesday. More rain is expected on Thursday, mainly across the northern and eastern mountains. The rain will gradually subside on Friday with a drying and warming trend expected this weekend. Wetter and cooler weather will return early next week. && .DISCUSSION... Radar is starting to show the north-south orientation to the precip, with a band extending along the Oregon/Idaho border north of Ontario up to Lewiston. 04Z RAP run has this fairly well depicted, along with the small area of rain south of Spokane. The RAP expects this area of rain to fall apart, which agrees with latest radar trends. Then the north-south band of rain should move into the southern panhandle and reach the BC border by about sunrise Wednesday. Models continue to show a done-deal for moderate rain in the panhandle including Coeur d`Alene, but more iffy to the west (e.g. Spokane airport). I have backed off a smidge on the rainfall amounts a bit from the previous forecast as the new GFS agrees somewhat with the new NAM. I also removed any mention of thunder from Wednesday`s forecast. While there is an outside chance of a strike or 2 away from the main band of rain, it`s just not worth keeping in the forecast, as models don`t show any surface-based instability due to the extensive cloud cover and the cold pool staying to our south. RJ && .AVIATION... 06Z TAFS: A band of moderate rain will develop over the Idaho Panhandle tonight and persist through much of Wednesday. This will bring MVFR/IFR conditions to most of the TAFs (aside from KEAT and KMWH). KCOE will likely be IFR all day long. KSFF will also see some near-IFR conditions. Tougher call at KGEG which will be on the western edge of the rain band. KPUW will likely have an IFR cig in the morning but improve a bit in the afternoon. To the west, KMWH and KEAT will just have VFR clouds. Gusty west winds will develop in the late afternoon at KEAT in response to a strong pressure gradient. RJ && .PRELIMINARY POINT TEMPS/POPS... Spokane 51 54 45 55 44 61 / 100 100 80 80 50 60 Coeur d`Alene 52 54 46 54 42 60 / 100 100 100 90 50 60 Pullman 49 53 44 56 42 60 / 100 100 70 60 30 60 Lewiston 56 58 49 64 44 67 / 100 100 70 60 20 50 Colville 54 63 50 57 48 67 / 60 100 100 100 60 50 Sandpoint 54 56 46 53 45 60 / 100 100 100 100 60 60 Kellogg 50 51 44 51 39 57 / 100 100 100 100 50 60 Moses Lake 54 66 51 65 49 69 / 20 40 50 60 30 30 Wenatchee 52 66 52 64 51 68 / 30 40 50 60 40 30 Omak 54 66 51 64 50 69 / 20 70 70 80 60 50 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
835 AM PDT WED JUN 19 2013 .DISCUSSION...AS OF 08:35 AM PDT WEDNESDAY...THE UPPER LEVEL TROUGH THAT MOVED ACROSS NORTHERN CALIFORNIA YESTERDAY SUCCESSFULLY CLEARED OUT THE MARINE LAYER OVERNIGHT. THIS MORNING THE SKIES ARE MOSTLY CLEAR WITH COOLER MORNING TEMPERATURES. WENT AHEAD AND DID A QUICK FORECAST UPDATE TO REMOVE CLOUDS AND FOG FROM THE FIRST PERIOD FORECAST. EXPECTING SLIGHTLY WARMER TEMPERATURES TODAY UNDER SUNNY SKIES. A WEAK UPPER LEVEL RIDGE IS FORECAST TO BUILD IN OVER THE WEST DURING THE NEXT FEW DAYS. THIS WILL ALLOW A GRADUAL WARMING TREND THAT WILL LAST INTO THE WEEKEND. BY SATURDAY HIGHS ARE EXPECTED TO WARM INTO THE 60S AND 70S COAST SIDE...80S AROUND THE BAY WITH LOWER TO MID 90S POSSIBLE IN THE WARMEST INTERIOR LOCATIONS. TEMPERATURES ARE PROGGED TO COOL OFF BEGINNING ON SUNDAY AS AN UPPER TROUGH RE-ESTABLISHES ALONG THE COAST. LAST NIGHT`S RUN OF THE ECMWF EVEN BRINGS PRECIPITATION TO NORTHERN CALIFORNIA INCLUDING THE NORTHERN PORTIONS OF OUR CWA BY MONDAY AND TUESDAY. THIS WOULD BE NICE IF IT VERIFIES...BUT WILL WAIT A FEW MORE MODEL RUNS BEFORE COMPLETELY BUYING INTO THIS SCENARIO. SUMMER BEGINS AT 05:04Z ON JUNE 21ST...OR 10:04 PM PDT JUNE 20TH. && .AVIATION...AS OF 4:40 AM PDT WEDNESDAY...EXTREMELY DIFFICULT FORECAST THIS MORNING AS NUMEROUS UPPER LEVEL IMPULSES MOVE EAST ACROSS THE AREA AROUND AN UPPER LOW OVER THE CA/OR BORDER. THIS UPPER LOW HAS CAUSED MANY PROBLEMS THE PAST FEW DAYS...WASHING OUT THE MARINE LAYER AND MAKING IT VERY DIFFICULT TO FORECAST STRATUS FORMATION AND DISSIPATION. PATCHY STRATUS DEVELOPED YESTERDAY EVENING AND CONTINUES TO SLOWLY EXPAND. MOST TERMINALS WILL SEE BRIEF MVFR TO IFR CIGS THROUGH 16Z. SHORT TERM MODELS INCLUDING THE HRRR AND THE LOCAL WRF INDICATE THAT VFR CONDITIONS WILL PREVAIL AFTER 16Z. LOW CONFIDENCE. OTHERWISE...MODERATE ONSHORE FLOW THIS AFTERNOON INTO THE EARLY EVENING HOURS. VICINITY OF KSFO...PATCHY MVFR CIGS WILL BE PRESENT NEAR THE TERMINAL THROUGH AT LEAST 16Z. VERY LOW CONFIDENCE. MODERATE TO STRONG WEST WINDS THIS AFTERNOON...WITH GUSTS TO JUST OVER 30 KT. KSFO BRIDGE APPROACH...PATCHY STRATUS IS MORE LIKELY TO IMPACT THE TERMINAL THROUGH 17Z. LOW CONFIDENCE. MONTEREY BAY AREA TERMINALS...PATCHY MVFR TO IFR CIGS THROUGH 16Z. LOW CONFIDENCE. MODERATE ONSHORE WINDS THIS AFTERNOON. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PT ARENA TO PT REYES 0-10 NM FROM NOON SCA...PT REYES TO PIGEON PT 0-10 NM FROM NOON SCA...PIGEON PT TO PT PINOS 0-10 NM FROM NOON SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 3 PM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL NOON GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM NOON SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM SCA...SF BAY FROM NOON SCA...MRY BAY FROM NOON && $$ PUBLIC FORECAST: SIMS AVIATION/MARINE: RILEY VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
441 AM PDT WED JUN 19 2013 .DISCUSSION...AS OF 03:45 AM PDT WEDNESDAY...500MB LOW PRESSURE CENTER NEARING THE OREGON COAST THIS MORNING WITH ASSOCIATED TROUGH AXIS POSITIONED ACROSS MUCH OF CALIFORNIA. IN ADDITION...THE STRATUS FORMATION HAS BEEN LIMITED THIS MORNING ACROSS THE REGION. EXPECTING WARMER TEMPERATURES THIS AFTERNOON AS THE TROUGH PUSHES FURTHER INLAND. 850MB TEMPERATURES ALSO FORECAST TO WARM THROUGH THE UPCOMING WEEKEND AS A RIDGE BUILDS IN AS THE UPPER LEVEL LOW ONLY SLOWLY MOVES EASTWARD. AT THE SURFACE...NORTHWEST WINDS WILL PREVAIL AND KEEP TEMPERATURES FROM WARMING TOO MUCH THROUGH THE WEEKEND. FORECAST MODELS CONTINUE TO DIFFER IN THEIR SOLUTIONS FOR THE EARLY PART OF NEXT WEEK AS THE NEXT UPPER LEVEL TROUGH DEVELOPS. COULD SEE AN INCREASE IN DEEPER MOISTURE PUSH INTO THE REGION...ESPECIALLY ACROSS THE NORTH BAY WHERE RAIN CHANCES COULD INCREASE. HOWEVER...FOR NOW WILL KEEP MENTION OF PRECIPITATION OUT OF THE FORECAST AND FOLLOW MORE OF A PERSISTENT PATTERN. && .AVIATION...AS OF 4:40 AM PDT WEDNESDAY...EXTREMELY DIFFICULT FORECAST THIS MORNING AS NUMEROUS UPPER LEVEL IMPULSES MOVE EAST ACROSS THE AREA AROUND AN UPPER LOW OVER THE CA/OR BORDER. THIS UPPER LOW HAS CAUSED MANY PROBLEMS THE PAST FEW DAYS...WASHING OUT THE MARINE LAYER AND MAKING IT VERY DIFFICULT TO FORECAST STRATUS FORMATION AND DISSIPATION. PATCHY STRATUS DEVELOPED YESTERDAY EVENING AND CONTINUES TO SLOWLY EXPAND. MOST TERMINALS WILL SEE BRIEF MVFR TO IFR CIGS THROUGH 16Z. SHORT TERM MODELS INCLUDING THE HRRR AND THE LOCAL WRF INDICATE THAT VFR CONDITIONS WILL PREVAIL AFTER 16Z. LOW CONFIDENCE. OTHERWISE...MODERATE ONSHORE FLOW THIS AFTERNOON INTO THE EARLY EVENING HOURS. VICINITY OF KSFO...PATCHY MVFR CIGS WILL BE PRESENT NEAR THE TERMINAL THROUGH AT LEAST 16Z. VERY LOW CONFIDENCE. MODERATE TO STRONG WEST WINDS THIS AFTERNOON...WITH GUSTS TO JUST OVER 30 KT. KSFO BRIDGE APPROACH...PATCHY STRATUS IS MORE LIKELY TO IMPACT THE TERMINAL THROUGH 17Z. LOW CONFIDENCE. MONTEREY BAY AREA TERMINALS...PATCHY MVFR TO IFR CIGS THROUGH 16Z. LOW CONFIDENCE. MODERATE ONSHORE WINDS THIS AFTERNOON. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...PT ARENA TO PT REYES 0-10 NM FROM NOON SCA...PT REYES TO PIGEON PT 0-10 NM FROM NOON SCA...PIGEON PT TO PT PINOS 0-10 NM FROM NOON SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 3 PM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL NOON GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM NOON SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM SCA...SF BAY FROM NOON SCA...MRY BAY FROM NOON && $$ PUBLIC FORECAST: RGASS AVIATION/MARINE: RILEY VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS PUEBLO CO
906 AM MDT WED JUN 19 2013 .UPDATE... ISSUED AT 857 AM MDT WED JUN 19 2013 UPDATED GRIDS FOR CURRENT TEMPERATURE TRENDS AND SKY CONDITIONS. ALSO REFRESHED ALL FIRE WEATHER GRIDS WITH 12Z NAM12 DATA. -PJC && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM MDT WED JUN 19 2013 ...ISOLATED SEVERE THREAT FAR EASTERN PLAINS...FIRE WEATHER OVER MTNS/VALLEYS... CURRENTLY... AN ISOLATED STRONG TO SEVERE STORM HAS BEEN TRACKING OVER THE FAR SOUTHEAST PLAINS EARLY THIS MORNING. STORM HAS TRACKED IN REMOTE AREAS SO NO REPORTS...BUT ALGORITHMS HAVE BEEN INDICATING 2" HAIL WITH IT AT TIMES...AND MODEST ROTATION HAS BEEN OCCURRING ON AND OFF WITH THE CELL. OVER THE REST OF THE PLAINS...LLVL MSTR HAS REMAINED IN PLACE WITH SFC SE WINDS OVER THE REGION. SKIES HAVE CLOUDED UP OVER A GOOD PART OF THE PLAINS WITH CIGS IN THE MVFR/IFR CATEGORY. OVER THE INTERIOR MTNS...THE DRY AIR IS NOTED AS DWPTS ARE IN THE SINGLE DIGITS ACROSS THE SAN JUANS. TODAY... SIMULATIONS SHOW THE DRYLINE WILL REMAIN ON THE COLORADO SIDE OF THE CO/KS BORDER THIS AFTERNOON. ALTHOUGH TEMPS WILL BE WARMING ALOFT...CONVG ALONG THE BOUNDARY MAY ALLOW FOR ONE OR TWO STORMS TO FORM. LATEST HRRR WAS HINTING AT THIS. SPC ALSO HAS FAR E PLAINS IN SLIGHT RISK. CAPE IS FCST TO BE SIGNIFICANT...3000 J/KG...AND SHEAR WILL BE IN THE 35-45 KT RANGE...SO IF ANY STORM GOES UP IT WILL ROTATE AND IT WILL HAVE THE POTENTIAL TO PRODUCE SOME BIG HAIL. LCLS WILL BE HIGH SO TORNADO THREAT IS VERY LOW. OVER THE REST OF THE REGION...METEOROLOGICAL CONDITIONS WILL BE FAVORABLE FOR EXTREME FIRE BEHAVIOR GIVEN THE LOW DWPTS AND GUSTY SW WINDS. QUITE A FEW AREAS ON THE PLAINS HAVE RECEIVED SOME BENEFICIAL RAIN SO THE THREAT IS LESS ALONG THE I-25 CORRIDOR...HOWEVER IT WILL DRY OUT QUICKLY TODAY AND ANY AREAS WHICH HAVE NOT RECEIVED ANY SIGNIF RAIN WILL HAVE THE POTENTIAL FOR EXTREME FIRE BEHAVIOR. IT WILL BE MUCH WARMER TODAY THAN THE YESTERDAY...WITH HIGHS APPROACHING 100 OVER THE LOWER ARK RVR VALLEY. EXPECT 70S MTNS WITH 80S IN THE VALLEYS. TEMPS AROUND 90F WILL OCCUR IN MOST OF EL PASO COUNTY. TONIGHT... EXCEPT FOR THE SLIGHT CHANCE OF A SUPERCELL OVER THE FAR E PLAINS EARLY THIS EVENING...IT WILL BE DRY. RH RECOVERY WILL BE VERY POOR OVER THE MTNS...VALLEYS AND I-25 CORRIDOR REGION. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 323 AM MDT WED JUN 19 2013 ...HIGH FIRE DANGER... MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED WITH A SLOW MOVING SYSTEM OUT OF THE PACIFIC NORTHWEST INTO THE NORTHERN PLAINS AND PERSISTENT SOUTHWESTERLY FLOW ACROSS THE ROCKIES. THIS WILL PUT THE REGION UNDER FAVORABLE CONDITIONS FOR HIGH FIRE DANGER. THURSDAY THROUGH SATURDAY...STRONG DRY PERSISTENT SOUTHWESTERLY FLOW WILL ENCOMPASS SOUTHERN COLORADO THROUGH THIS PERIOD. THIS WILL SET THE STAGE FOR EXTREME FIRE DANGER FOR MUCH OF SOUTHERN COLORADO...ESPECIALLY WEST OF I-25. ALREADY HAVE A FIRE WEATHER WATCH OUT FOR THURSDAY AFTERNOON...AND WILL LIKELY NEED TO RAISE ONE FOR FRIDAY AFTERNOON AS WELL IN THE NEAR FUTURE. WIDESPREAD WINDS OF 20 TO 30 MPH ARE EXPECTED EACH AFTERNOON THROUGH SATURDAY WHILE HUMIDITY VALUES WILL DROP WELL BELOW 10 PERCENT. IN ADDITION THE AFTERNOON MIXING WILL ALLOW TEMPERATURES TO CLIMB INTO THE UPPER 90S TO LOWER 100S ACROSS THE PLAINS. THERE ARE SOME FIRE WEATHER CONCERNS EAST OF I-25 AS WELL...CONDITIONS WILL BE FAVORABLE HOWEVER FUEL STATUS AND RECENT HEAVY RAINS PRECLUDE ANY FIRE WEATHER HIGHLIGHTS AT THIS TIME. FINE FUELS WILL NEED TO BE WATCHED AND MAY CURE QUICKLY WITH PERSISTENT DRY AND WINDY CONDITIONS LEADING TO ENHANCED FIRE DANGER. THE ONLY AREA THAT MAY SEE ANY PRECIPITATION DURING THE EXTENDED PERIOD WILL BE THE FAR SOUTHEAST PLAINS ON FRIDAY AFTERNOON AND EVENING WHERE AN ISOLATED THUNDERSTORM WILL BE POSSIBLE...BUT CONFIDENCE IS LOW IN OCCURRENCE AT THIS TIME. SUNDAY THROUGH TUESDAY...THE UPPER PATTERN BEGINS TO SHIFT ON SUNDAY WITH THE UPPER SYSTEM OVER THE NORTHERN PLAINS EJECTING INTO THE GREAT LAKES AND HIGH PRESSURE BUILDING NORTHWARD OUT OF THE DESERT SOUTHWEST. TEMPERATURES MAY BE SLIGHTLY COOLER ON SUNDAY BEHIND A WEAK COLD FRONT...BUT WE SHOULD STILL MANAGE MID TO UPPER 90S ACROSS THE PLAINS BEFORE WARMING BACK UP FOR MONDAY AND TUESDAY. HUMIDITY VALUES WILL REMAIN LOW THROUGH THIS PERIOD...BUT WITH HIGH PRESSURE BUILDING OVERHEAD...WINDS SHOULD WEAKEN AND HELP REDUCE THE HIGH FIRE DANGER. THE EXCEPTION MAY BE THE CONTINENTAL DIVIDE AREA SUNDAY AND MONDAY WHERE SOUTHWESTERLY FLOW WILL REMAIN A BIT STRONGER BEFORE WEAKENING ON TUESDAY. THIS WILL NEED TO BE MONITORED. CURRENT MODEL PROJECTIONS INDICATING THAT WE WILL REMAIN DRY WITH NO CHANCES FOR PRECIPITATION EARLY TO MIDDLE NEXT WEEK. MOZLEY && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 323 AM MDT WED JUN 19 2013 MORNING LOW CIGS WILL AFFECT KCOS AND KPUB THROUGH ABOUT 14Z WITH VFR THROUGH THE REMAINDER OF THE VALID TAF PERIOD. KALS WILL BE VFR NEXT 24H. GUSTY SOUTHWEST WINDS WILL OCCUR AT ALL TAF SITES THIS AFTERNOON...WITH WIND GUSTS IN THE 20 TO 30 KT RANGE. && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ220>230. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR COZ220>230. && $$ UPDATE...PJC SHORT TERM...HODANISH LONG TERM...MOZLEY AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
630 AM EDT WED JUN 19 2013 .SYNOPSIS... THE THREAT OF SHOWERS AND THUNDERSTORMS WILL REMAIN ACROSS THE MIDLANDS AND CSRA TODAY AS A COLD FRONT SLOWLY SINKS SOUTHWARD ACROSS THE AREA. MOISTURE WILL DIMINISH FROM THE NORTH TONIGHT INTO THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN FOR THE WEEKEND AS INCREASINGLY WARM AND HUMID CONDITIONS RETURN. && .NEAR TERM /THROUGH TONIGHT/... THROUGH 9 AM...SURFACE COLD FRONT EXTENDING FROM BISHOPVILLE THROUGH NEWBERRY TO LINCOLNTON AT 10Z. SCATTERED SHOWERS ALONG AND SOUTH OF THE BOUNDARY. INSTABILITY WEAK AND FORCING LIMITED WITH PRECIPITABLE WATER RANGING FROM 1.50 TO 2.00 INCHES. AFTER 9 AM...THE SURFACE COLD FRONT SHOULD SLOWLY MOVE SOUTHWARD ACROSS THE AREA TODAY. THE LATEST RUC AND NAM MODELS INDICATE A WEAK SHORT WAVE CROSSING THE AREA TODAY. HAVE INCREASED POPS ACROSS THE SOUTHEAST TO LIKELY...KEPT CHANCE POPS FOR TODAY FOR THE THE REMAINDER OF THE AREA. THREAT FOR CONVECTION WILL GRADUALLY DIMINISH FROM THE NORTH TO SOUTH THROUGH THIS EVENING AS DRIER AND MORE STABLE AIR FILTERS IN. WENT NEAR CONSENSUS WITH HIGHS IN THE MID 80S AND LOWS IN THE MID TO UPPER 60S. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... MAINLY DRY WEATHER EXPECTED THURSDAY INTO FRIDAY NIGHT AS HIGH PRESSURE RIDGES IN FROM THE NORTH. HIGHEST PRECIPITABLE WATER WILL BE SOUTH OF THE CSRA. CONSENSUS MOS TEMPS LOOK REASONABLE WITH HIGHS IN THE 85 TO 90 DEGREE RANGE AND LOWS IN THE 60S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... MEDIUM RANGE MODELS IN FAIRLY GOOD AGREEMENT WITH A WEAK UPPER LEVEL LOW AFFECTING THE SOUTHEASTERN STATES. THE FLOW AROUND SURFACE HIGH PRESSURE LOCATED OFF THE ATLANTIC COAST WILL BRING INCREASING MOISTURE TO THE REGION. AS A RESULT WE CAN EXPECT A CHANCE OF MAINLY DIURNAL CONVECTIVE ACTIVITY...ALONG WITH SEASONABLY WARM TEMPERATURES. && .AVIATION /10Z WEDNESDAY THROUGH MONDAY/... A MIXTURE OF VFR AND IFR CONDITIONS AT THE TAF SITES THIS MORNING. MAINLY DUE TO LOW CEILINGS AND SOME LIGHT FOG. 88D CONTINUES TO SHOW ...MAINLY SHOWERS MOVING NORTHEAST ACROSS THE AREA THIS MORNING. THE ACTIVITY IS ALONG/SOUTH OF A COLD FRONT THAT IS TRYING TO MOVE SLOWLY SOUTHEAST OVER THE AREA. EXPECT CONDITIONS TO RETURN TO VFR AT ALL TAF SITES BETWEEN 12Z-14Z. AS LONG AS FRONTAL BOUNDARY IS ACROSS THE CWA...THERE WILL BE A CHANCE OF SHOWERS/THUNDERSTORMS THROUGH THE DAY. HAVE NOT INCLUDED ANY MENTION OF PRECIPITATION AT THIS TIME AS LACK OF CONFIDENCE OF PLACEMENT/TIMING OF SCATTERED SHOWERS. BY TONIGHT...MODEL TIME SECTIONS SHOW SOME LOW LEVEL MOISTURE WITH THE 06Z NAM MORE MOIST THAN THE 00Z GFS. EXPECT VFR CONDITIONS THROUGH 06Z...BUT SOME MVFR CONDITIONS MAY BE POSSIBLE BEYOND THE TAF PERIOD. EXTENDED AVIATION OUTLOOK...POSSIBLE MVFR CONDITIONS THURSDAY MORNING. A SLIGHT CHANCE OF MAINLY AFTERNOON/EVENING THUNDERSTORMS THROUGH THE PERIOD. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
622 AM EDT WED JUN 19 2013 .SYNOPSIS... THE THREAT OF SHOWERS AND THUNDERSTORMS WILL REMAIN ACROSS THE MIDLANDS AND CSRA TODAY AS A COLD FRONT SLOWLY SINKS SOUTHWARD ACROSS THE AREA. MOISTURE WILL DIMINISH FROM THE NORTH TONIGHT INTO THURSDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN FOR THE WEEKEND AS INCREASINGLY WARM AND HUMID CONDITIONS RETURN. && .NEAR TERM /THROUGH TONIGHT/... THROUGH 9 AM...SURFACE COLD FRONT EXTENDING FROM BISHOPVILLE THROUGH NEWBERRY TO LINCOLNTON AT 10Z. SCATTERED SHOWERS ALONG AND SOUTH OF THE BOUNDARY. INSTABILITY WEAK AND FORCING LIMITED WITH PRECIPITABLE WATER RANGING FROM 1.50 TO 2.00 INCHES. AFTER 9 AM...THE SURFACE COLD FRONT SHOULD SLOWLY MOVE SOUTHWARD ACROSS THE AREA TODAY. THE LATEST RUC AND NAM MODELS INDICATE A WEAK SHORT WAVE CROSSING THE AREA TODAY. HAVE INCREASED POPS ACROSS THE SOUTHEAST TO LIKELY...KEPT CHANCE POPS FOR TODAY FOR THE THE REMAINDER OF THE AREA. THREAT FOR CONVECTION WILL GRADUALLY DIMINISH FROM THE NORTH TO SOUTH THROUGH THIS EVENING AS DRIER AND MORE STABLE AIR FILTERS IN. WENT NEAR CONSENSUS WITH HIGHS IN THE MID 80S AND LOWS IN THE MID TO UPPER 60S. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... MAINLY DRY WEATHER EXPECTED THURSDAY INTO FRIDAY NIGHT AS HIGH PRESSURE RIDGES IN FROM THE NORTH. HIGHEST PRECIPITABLE WATER WILL BE SOUTH OF THE CSRA. CONSENSUS MOS TEMPS LOOK REASONABLE WITH HIGHS IN THE 85 TO 90 DEGREE RANGE AND LOWS IN THE 60S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... MEDIUM RANGE MODELS IN FAIRLY GOOD AGREEMENT WITH A WEAK UPPER LEVEL LOW AFFECTING THE SOUTHEASTERN STATES. THE FLOW AROUND SURFACE HIGH PRESSURE LOCATED OFF THE ATLANTIC COAST WILL BRING INCREASING MOISTURE TO THE REGION. AS A RESULT WE CAN EXPECT A CHANCE OF MAINLY DIURNAL CONVECTIVE ACTIVITY...ALONG WITH SEASONABLY WARM TEMPERATURES. && .AVIATION /10Z WEDNESDAY THROUGH SUNDAY/... VFR AT THE TERMINALS CURRENTLY. RADAR INDICATES A FEW SHOWERS/THUNDERSTORMS WELL TO THE NORTH OF THE TERMINALS. ONCE CONVECTION ASSOCIATED WITH A FRONTAL BOUNDARY DISSIPATES LATER TONIGHT...FOCUS WILL SHIFT TO ANY FOG/STRATUS THREAT FOR LATE TONIGHT/EARLY WED. LATEST GUIDANCE GENERALLY POINTING TO POSSIBILITIES OF MVFR CONDITIONS. AFTER ANY MORNING RESTRICTIONS...EXPECT VFR WEDNESDAY. SOME DRIER AIR WILL ENTER OUR FORECAST AREA BEHIND THE FRONT...WITH CHANCES OF CONVECTION WEDNESDAY MAINLY TO OUR SOUTH. CHANCES TOO LOW TO INCLUDE MENTION IN TAFS AT THIS TIME. EXTENDED AVIATION OUTLOOK...SLIGHT CHANCE OF MAINLY AFTERNOON/EVENING THUNDERSTORMS. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$ 77
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1012 AM EDT WED JUN 19 2013 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 402 AM EDT WED JUN 19 2013 HIGH PRESSURE WILL BUILD OVER CENTRAL INDIANA BRINGING DRY WEATHER THROUGH THE END OF THE WORK WEEK. AFTER A BRIEF DIP IN TEMPERATURES TODAY HIGHS WILL WARM BACK TO THE UPPER 80S TO LOW 90S FROM FRIDAY ON. SMALL CHANCES FOR THUNDERSTORMS WILL PERSIST FROM SATURDAY THROUGH TUESDAY AS WEAK WAVES MOVE THROUGH THE UPPER FLOW. && .NEAR TERM /REST OF TODAY/... ISSUED AT 930 AM EDT WED JUN 19 2013 FORECAST IS ON TRACK. ONLY SOME PATCHY MID CLOUD ACROSS THE AREA NOW...AND SCATTERED CU STILL LOOK LIKELY TO DEVELOP THIS AFTERNOON. STILL PLENTY OF SUNSHINE THOUGH. ONLY MADE MINOR TWEAKS TO HOURLY FORECASTS. RELEVANT PORTION OF PREVIOUS DISCUSSION FOLLOWS... HIGH PRESSURE WILL BUILD OVER THE AREA TODAY WITH WEAK COLD ADVECTION AT 850 MB AND LIGHT EASTERLY WINDS USHERING IN DRIER AIR. WITH 850 MB TEMPERATURES FALLING TO 11-12C ACROSS THE AREA WENT A DEGREE OR TWO COOLER THAN MAV NUMBERS. DAY WILL START OUT CLEAR BUT TIME HEIGHTS INDICATE SOME LEFTOVER MOISTURE AROUND 850 MB SO COULD SEE SOME SCATTERED CU IN THE AFTERNOON. && .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... ISSUED AT 402 AM EDT WED JUN 19 2013 FORECAST FOCUS IS ON TEMPERATURES. MODELS WERE GENERALLY IN GOOD AGREEMENT SO USED A CONSENSUS APPROACH. UPPER RIDGING BUILDS ACROSS THE AREA THROUGH THE SHORT TERM. FOR TONIGHT PREFERRED COOLER GUIDANCE NUMBERS UNDER A MOSTLY CLEAR SKY. AS THE SURFACE HIGH SHIFTS EAST SHOULD SEE WARM ADVECTION RAMP UP AND EXPECT SIGNIFICANT WARMING TREND WITH INCREASING HUMIDITY THURSDAY INTO FRIDAY. USED A GUIDANCE CONSENSUS FOR THURSDAY BUT WENT WITH WARMER GUIDANCE ON FRIDAY. WHILE THERE ARE SOME INDICATIONS THAT A BREAKDOWN IN THE RIDGE COULD TAKE PLACE AS EARLY AS FRIDAY GENERAL CONSENSUS IS THAT BREAKDOWN WILL OCCUR OVER THE NORTHERN GREAT LAKES AND THUS KEEP CENTRAL INDIANA DRY. && .LONG TERM /SATURDAY THROUGH TUESDAY/... ISSUED AT 402 AM EDT WED JUN 19 2013 AN UPPER RIDGE WILL DOMINATE OUR WEATHER MUCH OF THE PERIOD. THE GFS SUPPRESSES IT A LITTLE SOUTHWARD TOWARDS DAY 6 AND 7. WHILE THE GEM AND OLD EURO DID NOT. THERE ARE A COUPLE OF SHORT WAVES THAT WILL BE COMING OVER THE TOP OF THE RIDGE THAT MAY PRODUCE LOW CHANCES OF THUNDERSTORMS. THE 12Z EURO INDICATED A PRETTY GOOD CHANCE OF THUNDERSTORMS ACROSS OUR NORTH SATURDAY WITH LESSER CHANCES TOWARDS END OF THE EXTENDED. THE GFS INDICATED VERY LOW CHANCES OF PRECIP ACROSS OUR NORTH OVER THE WEEKEND WITH BETTER CHANCES ALL AREAS TOWARDS DAY 7. 700 MB TEMPERATURES ARE MOSTLY 8 TO 10 CELSIUS RANGE WOULD ALLOW A FEW THUNDERSTORMS. FOR NOW WILL LEAVE 20 PERCENT CHANCE POPS MOST PERIODS...BUT MAINLY OVER NORTHERN SECTIONS OVER THE WEEKEND. WENT CLOSE TO A MOS BLEND ON TEMPERATURES. SOME CASES THE ALL BLEND MAX TEMPERATURES SEEM TO BE A BIT TOO COOL AND LEANED CLOSER TO MEX VALUES. && .AVIATION /DISCUSSION FOR THE 191500Z TAF UPDATE/... ISSUED AT 1012 AM EDT WED JUN 19 2013 FORECAST IN GOOD SHAPE THIS MORNING AS HIGH PRESSURE EXPANDS SOUTH INTO THE REGION. EXPECT SOME CU DEVELOPMENT THROUGH THE AFTERNOON... ESPECIALLY AT KBMG AND KHUF WHERE LOW LEVEL MOISTURE IS A BIT MORE PREVALENT AND CURRENT RAP ANALYSIS INDICATING PRESENCE OF A SUBTLE 850MB THERMAL TROUGH. 12Z DISCUSSION FOLLOWS. VFR THROUGH THE FORECAST PERIOD. HIGH PRESSURE MOVING EAST ACROSS THE GREAT LAKES WILL PRODUCE A LIGHT EAST TO NORTHEAST FLOW WITH DRIER AIR SPREADING INTO THE REGION. CU RULE INDICATES A LITTLE CU. EXPECT ONLY FEW CU AT KIND AND KLAF AND SCT CU ELSEWHERE LATE THIS MORNING AND AFTERNOON. MODEL SOUNDINGS INDICATE MOSTLY CLEAR CONDITIONS TONIGHT WITH SOME HIGH CLOUDS LATE TONIGHT. WINDS WILL BE EAST UP TO 8 KNOTS TODAY BECOMING LIGHT TONIGHT. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP/50 SHORT TERM...CP LONG TERM....JH AVIATION...JH/RYAN VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
638 AM CDT WED JUN 19 2013 .SHORT TERM.../TODAY/... ISSUED AT 339 AM CDT WED JUN 19 2013 HIGH PRESSURE RIDGE MOVING OFF TO THE EAST NOW WITH WAA BEGINNING TO MOVE INTO WRN IA. SAT PIX SHOW AN INCREASE IN CLODS FROM DECAYING BLOWOFF CLOUDS. DEEPER MOISTURE CONVERGENCE MOVING INTO SWRN IA WILL BRING AT LEAST ISOLATED TSRA THIS MORNING AS WAA ARC LIFTS NORTHEAST ACROSS THE CWA. KEPT THE PRECIP TO THE WEST HALF HOWEVER. COMBINATION OF NAMDNG5 AND HRRR GIVES A REASONABLE PRESENTATION OF EXPECTED OUTCOME. TEMPS TODAY VERY DEPENDENT ON CLOUD COVER. FEEL THERE WILL BE ENOUGH BREAKS TO GET HIGHS A LITTLE ABOVE MOS GUID AND WARMER THAN YESTERDAY IN MOST LOCATIONS. .LONG TERM.../TONIGHT THROUGH TUESDAY/... ISSUED AT 339 AM CDT WED JUN 19 2013 COMPLICATED FORECAST FOR EXTENDED...WITH MANY PERIODS OF POPS...AND SOMEWHAT LOW CONFIDENCE IN TIMING...WITH BREAKS IN PRECIP CHANCES FROM TIME TO TIME THROUGH THE REMAINDER OF THE WEEK. LARGE UPPER LEVEL LOW WILL BE DRIVER FOR PRECIPITATION CHANCES TROUGH MUCH OF THE PERIOD. LOW WILL REMAIN PRIMARILY OVER PAC NW...AND IS BEGINNING TO SLOWLY PUSH INLAND ATTM. MODELS HAVE SIGNIFICANT DISCREPANCIES OVER PLACEMENT OF LOW...BUT SHOULD COME INTO BETTER AGREEMENT AS LOW PUSHES INLAND. RIDGE REMAINS OVER IOWA THROUGH MUCH OF PERIOD...WITH SHORTWAVES PUSHING THROUGH SPARKING CONVECTION CHANCES. MODELS HAVE SIGNIFICANTLY SLOWED DOWN SHORT WAVES PROPAGATION EASTWARD...WITH FOCUS FOR DEVELOPMENT IN CENTRAL NE PUSHING INTO IOWA LATE OVERNIGHT. HAVE THEREFORE SLOWED POPS FOR OVERNIGHT...THOUGH COULD SEE SOME DEVELOPMENT AHEAD OF MAIN PRECIP BAND WITH THETA-E ADVECTION. SYSTEM IS SLOW MOVING...WITH PRECIP THROUGH THURSDAY. STRONG SHORTWAVE SET TO TRACK ACROSS NORTHERN PLAINS LATE THURSDAY. THIS WILL LIKELY BE THE FOCUS FOR SEVERE WEATHER ACROSS THE DAKOTAS...AND MAY FORM INTO MCS PUSHING ACROSS IOWA...WITH NORTHERN IOWA MOST LIKELY LOCATION OVERNIGHT THURSDAY. SEVERE WEATHER WILL BE POSSIBLE WITH THIS SYSTEM. SHORTWAVE EXPECTED TO TRACK ACROSS SOUTHERN SD/MN AND HEAVIEST PRECIP MAY STAY NORTH. NUMEROUS SHORTWAVES CONTINUE TO TRACK EAST AS UPPER LEVEL LOW REMAINS ACROSS NORTHWESTERN US. AS LOW PUSHES EASTWARD...TRACKS OF WAVES WILL LIKELY GO NORTH OF CWA...BUT MAY SEE DEVELOPMENT FURTHER SOUTH...AND HAVE KEPT POPS ACROSS THE NORTH. SOMEWHAT STRONGER WAVE PUSHES THROUGH FLOW FOR THE WEEKEND...THOUGH UPPER LEVEL LOW WILL PUSH EASTWARD AND SURFACE LOW IN WESTERN PLAINS WILL ALSO LIFT NE AT THIS TIME...AND TIMING AND LOCATION FOR PRECIPITATION CHANCES OVER THE WEEKEND IS VERY MUDDLED. AS UPPER LEVEL LOW PUSHES EAST FRONT WILL DROP ACROSS IOWA WITH PROLONGED PRECIPITATION CHANCE FOR LATE IN THE PERIOD. TEMPERATURES WILL WARM SIGNIFICANTLY UNDER THE RIDGE...WITH SURFACE SOUTHERLY FLOW. HAVE BUMPED TEMPERATURES UP WITH WAA FOR EARLY IN THE PERIOD...THOUGH MIXING MAY BE SOMEWHAT LIMITED. OVERALL...TEMPERATURES WILL WARM WITH SUMMER LIKE READINGS. && .AVIATION...19/12Z ISSUED AT 632 AM CDT WED JUN 19 2013 A SELY FLOW OF WILL BRING MOISTURE NORTH INTO THE STATE AND RESULT IN ISOLATED SHRA OVER THE WRN TAF SITES THIS MORNING. VFR CONDITIONS WILL HOLD THROUGH THE TAF PERIOD WITH MID AND HIGH LEVEL CIGS. TSRA WILL MOVE INTO WRN A TONIGHT...BUT AT THIS TIME THINKING IS THAT THE TSRA WILL REMAIN MAINLY WEST OF THE TAF SITES WITH ONLY A SMALL CHANCE OF THEM REACHING KFOD AND KDSM BY 12Z. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...MS JUN 13 LONG TERM...AWB AVIATION...MS JUN 13
AREA FORECAST DISCUSSION
NWS WICHITA KS
634 AM CDT WED JUN 19 2013 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 330 AM CDT WED JUN 19 2013 TOUGH FORECAST WAS MADE EVEN MORE DIFFICULT DUE TO THE UNAVAILABILITY OF HRRR/00 UTC ECMWF AND RUC AFTER 0600 UTC DUE TO PROBLEMS UPSTREAM. NONE OF THE REMAINDER OF AVAILABLE GUIDANCE HAD MUCH OF A HANDLE ON ONGOING CONVECTION. NAM WAS PARTICULARLY SUSPECT...ESPECIALLY WITH INITIALIZATION OF 850MB MOISTURE. BASED ON 0000 UTC RADIOSONDE OBSERVATION AND OBSERVATIONAL DATASETS... SEE LITTLE REASON WHY HIGH PLAINS CONVECTION WILL NOT CONTINUE TO ROLL EAST DURING THE DAY AIDED BY WARM AIR ADVECTION...INFLUX OF MOISTURE AND SHORTWAVE. EFFECTS ON TEMPERATURES/WINDS DURING THE DAY WILL BE DIFFICULT TO PIN DOWN. THINKING THAT PRECIPITATION WILL TRANSITION TO EASTERN HALF BY LATE AFTERNOON...WITH LULL IN THE WESTERN HALF AROUND SUNSET. SEE NO REASON WHY STORMS WILL NOT DEVELOP OVER THE HIGH PLAINS AGAIN TONIGHT AND ROLL EAST. THU REMAINS PROBLEMATIC...AS IT IS UNCLEAR HOW WIDESPREAD CONVECTION WILL BE OR LOW LONG IT WILL LINGER. LARGE POTENTIAL FOR ERROR ON ALL FACETS OF THIS FORECAST. HAVE LEANED A BIT TOWARDS THE GFS WHICH WAS THE LEAST WRONG GUIDANCE OUT OF THE BOX. HAVE STAYED THE COURSE WITH DRY/WARMER/WINDIER CONDITIONS ON FRIDAY. -HOWERTON .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 330 AM CDT WED JUN 19 2013 THE WARMING TREND WILL CONTINUE INTO THE WEEKEND AS RIDGE BUILDS. SOME HINT ON THE LATEST AVAILABLE GUIDANCE THAT FRONT MAY SAG CLOSE ENOUGH TO BRING SMALL CHANCES FOR PRECIPITATION ON SUN/SUN NIGHT. NOT OVERLY OPTIMISTIC ABOUT THESE CHANCES BUT IN ABSENCE OF 0000 UTC ECMWF WILL NOT MAKE SIGNIFICANT CHANGES. HAVE HEDGED TEMPERATURES UP A BIT ABOVE INITIALIZATION GRIDS BASED ON LAST WARM PERIOD AND BEST GUIDANCE AT THESE TIME RANGES. TEMPERATURES IN TRIPLE DIGITS APPEAR PROBABLE IN CENTRAL KS BY EARLY NEXT WEEK. -HOWERTON && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 632 AM CDT WED JUN 19 2013 HIGH CLOUDS WILL FLOAT OVERHEAD THIS MORNING GIVING WAY TO MID- LEVEL CUMULUS CLOUDS IN THE AFTERNOON. MEANWHILE SOUTHERLY WINDS WILL INCREASE ACROSS THE ENTIRE REGION TODAY...AS THE PRESSURE GRADIENT TIGHTENS UP FROM DEEPENING SURFACE LOW PRESSURE OVER NORTHEAST COLORADO. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER WESTERN KANSAS LATER TODAY AND MOVE EASTWARD INTO CENTRAL KANSAS. JAKUB && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 84 70 90 73 / 40 40 30 10 HUTCHINSON 87 69 91 72 / 40 50 20 10 NEWTON 85 68 89 72 / 40 40 30 10 ELDORADO 83 69 88 73 / 40 40 40 10 WINFIELD-KWLD 84 70 89 73 / 40 40 30 10 RUSSELL 89 68 94 71 / 50 50 10 10 GREAT BEND 89 68 93 72 / 50 50 10 10 SALINA 88 70 90 75 / 40 50 30 10 MCPHERSON 87 69 90 72 / 40 50 30 10 COFFEYVILLE 90 69 86 73 / 40 30 30 10 CHANUTE 88 68 84 72 / 40 30 30 10 IOLA 88 68 83 71 / 40 40 30 10 PARSONS-KPPF 89 69 84 72 / 40 30 30 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
531 AM MDT WED JUN 19 2013 .SHORT TERM...(TODAY THROUGH FRIDAY NIGHT) ISSUED AT 402 AM MDT WED JUN 19 2013 MAIN FORECAST PROBLEM THUNDERSTORM COVERAGE/CHANCES THROUGH PERIOD WITH HOW HOT DOES IT GET THURSDAY AND FRIDAY. SATELLITE CONTINUING TO SHOW AN AMPLIFIED/BLOCKY/COMPLICATED UPPER FLOW FROM THE EASTERN PACIFIC INTO THE CENTRAL PORTION OF THE COUNTRY. UPPER LOW HAS MOVED CLOSER TO THE PACIFIC NORTHWEST WITH WEST TO SOUTHWEST FL0W ALOFT SPREADING ACROSS OUR AREA. COLD FRONT REMAINS WELL TO OUR SOUTH AND IS DRAPED UP AGAINST THE COLORADO FRONT RANGE. LARGE COMPLEX OF THUNDERSTORMS HAS PRODUCED A SIGNIFICANT COLD POOL AND HAS SENT UP MESOSCALE/CONVERGENT BOUNDARIES ACROSS DIFFERENT PORTIONS OF THE REGION. MODELS INITIALIZED FINE AT JET LEVEL. THE NAM/ECMWF LOOKED TO HAVE INITIALIZED THE WORST ON THE MID LEVELS WITH THE UKMET/CANADIAN/GFS/SREF DOING ABOUT THE SAME. NAM WAS A LITTLE WARM AT 700 MB WITH THE GFS AND UKMET BETTER. SREF AND GFS WERE DOING LITTLE BETTER THAN THE NAM AND CANADIAN ON THE LOW LEVEL THERMAL FIELD. TODAY/TONIGHT...DUE TO THE OVERNIGHT THUNDERSTORM COMPLEX THAT WENT THROUGH...MESOSCALE BOUNDARIES/CONVERGENCE DO ABOUND. SATELLITE AND UPPER AIR ANALYSIS SHOWING A COUPLE OF WEAK SHORTWAVES TO OUR WEST PLUS A WARMER AND DRIER MID LEVEL AIR MASS/EML MOVING IN FROM THE WEST. NEAR 12Z THE LEFT FRONT QUADRANT OF SOUTHERN JET WILL BE AFFECTING THE SOUTHWEST PORTION OF THE AREA. IT STAYS NEAR THE SOUTHERN PORTION OF THE AREA THROUGH AS SLOWLY PROGRESSES SOUTH AWAY FROM THE AREA. VERY UNCERTAIN PRECIPITATION FORECAST FOR THE DAY...ESPECIALLY THIS MORNING...WITH MESOSCALE FEATURES BEING A BIG INFLUENCE. CONVECTIVE CIRCULATION IS LOCATED OVER THE EASTERN PORTION OF THE AREA. ONE OF THOSE OUTFLOW BOUNDARIES LIES ACROSS THE NORTHEAST PORTION. ALL MODELS ESPECIALLY THE RAP REDEVELOPS A SIGNIFICANT PRECIPITATION AREA OVER THE NORTHEAST TO EAST PORTION OF THE AREA THIS MORNING. CONSIDERING THAT THE RAP HAS BEEN CONSISTENT FOR A COUPLE OF RUNS... MATCHES UP WITH WHERE THE BOUNDARY IS RIGHT NOW AND THAT THUNDERSTORMS HAVE REDEVELOPED ALREADY IN THE SAME GENERAL AREA... WILL RAISE POPS TO A HIGH CHANCE THIS MORNING AND CONTINUE TO MONITOR. THAT CIRCULATION AND PRECIPITATION LOOK TO EXIT THE AREA AROUND THE MIDDLE OF THE DAY. THE AIR MASS LOOKS TO RELOAD WITH EMPHASIS SHIFTING BACK TO THE WEST. SURFACE TROUGH STILL REMAINS TO THE WEST OF THE AREA. WHAT LOOKS TO BE A DRYLINE SETS UP OVER THE FAR WEST WITH THE INSTABILITY AXIS SETTING NEAR THE COLORADO AND KANSAS BORDER. THE FAR WESTERN MAY BE CAPPED THIS AFTERNOON. SHORTWAVE TROUGH MOVES IN FROM THE WEST AND EXPECT THUNDERSTORMS TO DEVELOP NEAR OR JUST TO THE EAST OF THE COLORADO BORDER. THESE STORMS SHOULD PROGRESS TO THE EAST THROUGH THE NIGHT AS THE SHORTWAVE MOVES TOWARD THE EAST AND THE LOW LEVEL JET DEVELOPS IN THE EASTERN THIRD. DO NOT HAVE A GOOD FEEL WITH THE HIGH TEMPERATURES. IT IS POSSIBLE WITH THE WET GROUND AND ONGOING CLOUD COVER AND PRECIPITATION COULD CAUSE TEMPERATURES TO BE COOLER...ESPECIALLY IN THE EAST. THURSDAY/THURSDAY NIGHT...INTERESTING FORECAST FOR THIS DAY. 700 MB TEMPERATURES REMAIN RATHER HIGH THROUGH THE DAY...WITH THE LOWEST AND CAP BREAKABLE TEMPERATURES IN THE NORTHERN AND EASTERN PORTIONS OF THE AREA. BY LATE AFTERNOON...EITHER A WEAK COOL FRONT OR SURFACE TROUGH SAGS INTO THE NORTHERN PORTION OF THE AREA WITH WHAT LOOKS TO BE A DRYLINE JUST TO THE WEST OF THE SOUTHEAST CORNER. AT THE SAME TIME A SHORTWAVE TROUGH APPROACHES FROM THE SOUTHWEST. ALL THESE FEATURES PROGRESS NORTH AND EAST THROUGH THE EVENING. BY LATE IN THE AFTERNOON A WEAK LEFT FRONT QUADRANT LOOKS TO BE JUST SOUTH OF THE FORECAST AREA. THIS LIFT MOVES SLOWLY NORTH THROUGH THE EVENING AND WILL BE AFFECT THE SOUTHEAST QUARTER BY LATE IN THE NIGHT. MODELS ARE GENERATING SOME LIGHT QPF EVEN WITH WHAT LOOKS TO BE A DEEP DRY LAYER AND HIGH BASES. BELIEVE THERE IS ENOUGH HERE TO INCLUDE A LOW SLIGHT CHANCE. HOWEVER...COULD SEE THINGS TOTALLY CAPPED OR BE ABLE TO BREAK LOOSE. ALONG AND NORTH OF THE BOUNDARY THE TEMPERATURES WILL BE SLIGHTLY COOLER...IN THE 90S. SOUTH THE BOUNDARY IT WILL BE NEAR 100 DEGREES. MODELS DO DISAGREE WITH HOW FAR SOUTH TO TAKE THE BOUNDARY. CONSIDERING THE FLOW ALOFT AND THE AIR MASS LIKE THE BOUNDARY BEING FURTHER NORTH. FRIDAY/FRIDAY NIGHT...THE CANADIAN AND ECMWF KEEP A WEAK LEFT FRONT QUADRANT OF THE JET NEAR/OVER THE EASTERN AND CENTRAL PORTION OF THE AREA THROUGH THE DAY. VERY SIMILAR SETUP TO THE DAY BEFORE EXCEPT MOST OF THE WEST AND CENTRAL PORTIONS DO LOOK CAPPED DESPITE THE SURFACE TROUGH AND DRYLINE NEAR THE SAME PLACE. THE EASTERN THIRD HAS THE LOWER 700 MB TEMPERATURES WITH THE INSTABILITY AXIS AND BEST MID LEVEL MOISTURE IN THE SAME AREA. AT THE SAME TIME A SHORTWAVE TROUGH IS COMING ACROSS. LIKED WHAT THE PREVIOUS SHIFT HAD IN THERE FOR A SLIGHT CHANCE AND ONLY MADE A SLIGHT ADJUSTMENT TO THE AREA FOR THE AFTERNOON AND EVENING HOURS. ONCE AGAIN HIGH TEMPERATURES WILL BE DETERMINED BY WHERE THE BOUNDARY SETS UP. MODEL DATA SAYS THE BOUNDARY WILL BE A LITTLE FURTHER NORTH AND SO WILL THE HOT TEMPERATURES AND TRENDED THE MAXES IN THAT DIRECTION. .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 230 AM MDT TUE JUN 19 2013 STRONG SOUTHWEST FLOW ALOFT AT 500 MB WILL PERSIST THROUGHOUT THE DAY SATURDAY AS MERIDIONAL FLOW PATTERN EXISTS OVER THE CENTRAL PLAINS. INSTABILITY WILL BE PRESENT IN THE FLOW AS EMBEDDED SHORTWAVE TROUGHS ENTER INTO OUR FORECAST AREA. AN UPPER LEVEL LOW WILL PROGRESS WESTWARD OVER THE NORTHERN HIGH PLAINS AS BLOCKING RIDGE OVER THE SOUTHERN PLAINS STRENGTHENS SATURDAY EVENING INTO SUNDAY. STRONGEST UPPER LEVEL JET WILL STAY IN THE NORTHERN PLAINS ALONG WITH STRONGEST POSITIVE VORTICITY VALUES...HOWEVER SOME POCKETS OF POSITIVE VORTICITY WILL ENTER THE TRI STATE AREA FOR SUNDAY AFTERNOON AND EVENING. THE TROUGH BECOMES NEGATIVELY TILTED AS FLOW PATTERN RETURNS TO ZONAL FLOW FOR SUNDAY EVENING AND MONDAY. THE RIDGE TO THE SOUTH WILL CONTINUE TO STRENGTHEN AND MOVE INTO THE CENTRAL PLAINS FOR TUESDAY...AND JET STREAM WILL STAY WELL TO THE NORTH OF THE AREA FOR THE REST OF NEXT WEEK. 850 MB JET SPEEDS ARE VERY STRONG DUE TO NOCTURNAL EFFECT FOR OVERNIGHT SATURDAY AND SUNDAY TOWARD WEST CENTRAL KANSAS...WHICH COULD PROVIDE SOME UNSTABLE WEATHER WITH UPPER LEVEL SHORTWAVE FORCING. ONCE RIDGE BUILDS INTO THE REGION...THE JET SPEEDS WILL DECREASE AND BECOME CALM FOR THE REST OF NEXT WEEK. AT THE SURFACE...STRONG WARM AIR ADVECTION WILL BE PRESENT ACROSS THE AREA WITH TEMPERATURES REACHING THE MID TO UPPER 90S FOR THE WEEKEND. 850 MB TEMPERATURES ARE ALSO WARM...WITH VALUES IN THE MID 80S SATURDAY AND SUNDAY. THETA E VALUES ARE MARGINAL AT 850 AND AT THE SURFACE...WITH HIGHER VALUES TOWARD CENTRAL KANSAS. DEW POINTS WILL BE IN THE MID 50S ACROSS THE REGION...WITH A 30 DEGREE DRY LINE GRADIENT PRESENT IN THE WESTERN CWA. ALTHOUGH BEST SURFACE BOUNDARY EXISTS FOR THE AREA SATURDAY AND SUNDAY...INSTABILITY PARAMETERS ARE MARGINAL AT BEST. THERE ARE SOME CHANCES FOR THUNDERSTORM DEVELOPMENT SATURDAY AND SUNDAY AFTERNOON...BUT THE BEST CHANCE IS TO THE EAST TOWARDS MORE UNSTABLE ENVIRONMENT IN CENTRAL KANSAS. STRONG SOUTH/SOUTHWEST FLOW WILL RETURN TO THE REGION FOR MONDAY AFTERNOON AND FOR THE REST OF THE WEEK...BRINGING WARM AIR AND DRY CONDITIONS TO MUCH OF THE AREA. AFTERNOON AND EVENING THUNDERSTORMS WILL DEVELOP ACROSS MUCH OF THE AREA FOR THE WEEKEND AS WARM FRONT INCREASES TEMPERATURES. MORE STABLE UPPER LEVEL AIR WILL MOVE INTO THE HIGH PLAINS REGION FOR NEXT WEEK...PROVIDING DRY CONDITIONS AND TEMPERATURES THAT MAY REACH NEAR 100. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 529 AM MDT WED JUN 19 2013 LOW PRESSURE SYSTEM TO THE WEST OF THE TAF SITES WILL HELP PRODUCE AFTERNOON AND EVENING THUNDERSTORMS AT KGLD AND KMCK. CONFIDENCE IS LOW AT THIS POINT AS TO LOCATION OF FORMATION...AS BEST CHANCES LOOK TO BE WEST OF THE TAF SITES IN THE COLORADO COUNTIES. THEREFORE...NO MENTION OF THUNDERSTORMS IN THE TAFS AT THIS TIME. LINGERING SHOWERS NEAR KMCK WILL DIMINISH AFTER 15Z. WINDS WILL BE BREEZY AT BOTH SITES TODAY...GUSTING TO 30 KTS AT TIMES. BOTH VISIBILITIES AND CEILING HEIGHTS FOR THE TERMINALS ARE EXPECTED TO BE VFR THROUGHOUT THE TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...MK AVIATION...MK
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
623 AM CDT WED JUN 19 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 410 AM CDT WED JUN 19 2013 CIRRUS SHIELD NOTED ON IR SATELLITE ENTERING FAR WESTERN MN. SHIELD IS JUST AHEAD OF DEEPENING SURFACE CYCLONE ABOVE EASTERN MONTANA. THIS FEATURE WILL BE EJECTED OUT OF 50H TROF OVER PACIFIC NW DURING THE NEXT 24 HOURS INTO WESTERN NODAK AND SOUTHERN SASKATCHEWAN. WARM FRONTAL BOUNDARY ATTACHED TO SURFACE CYCLONE WILL BE CATALYST FOR SCATTERED SHOWERS AND ISOLATE THUNDERSTORMS LATE THIS MORNING OVER FAR WESTERN CWA. USED GFS40 THETA E ADVECTION AND HRRR GUIDANCE FOR PLACEMENT AND TIMING OF DAYTIME CONVECTION OVER FA. COULD BE A FEW STRONG TO NEAR SEVERE THUNDERSTORMS THIS AFTERNOON OVER CENTRAL AND PORTIONS OF SW MN TO...AS JOULES INCREASE INTO THE 1500 TO 2500 RANGE. MODERATE 250MB DIVERGENCE COUPLETS ALSO NOTED OVER THESE AREAS ALONG WITH LI`S PLUNGING INTO THE NEGATIVE 4 TO NEGATIVE 8 CATEGORY. ONLY LIMITING FACTOR WOULD BE THICKER CLOUD DECK THEN CURRENT CIRRUS SHIELD PROGGED FOR MUCH OF THE DAYTIME HOURS. PRESENCE AND PROGRESSION OF WARM FRONTAL BOUNDARY DEEPER INTO SOUTHERN HALF OF MN TONIGHT SHOULD PORTEND SLIGHTLY ENHANCED CHANCES FOR CONVECTION...WITH QPF VALUES ALSO RISING NOTICEABLY. COULD BE A QUICK QUARTER INCH TO ONE HALF INCH OF MOISTURE GENERATE FROM CONTINUE SCT ACTIVITY DURING THE OVERNIGHT. 850MB LAPSE RATES AND LI`S WILL ALSO RISE SLIGHTLY OVERNIGHT. MODERATE SOUTHERLY LOW LEVEL JET WILL ALSO FORM BY LATE TONIGHT OVER MUCH OF MN FA ...WITH 25 TO 30KT MAGNITUDES COMMON SOUTH OF A LINE FROM ALEXANDRIA TO OWATONNA. COULD BE ADDITIONAL ISOLATED STRONG TO NEAR SEVERE T-STORMS OVER WESTERN HALF OF FA DURING THE EVENING...SWITCHING TO FAR EAST CENTRAL MN/WEST CENTRAL WI AFTER MIDNIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 410 AM CDT WED JUN 19 2013 WARM AND MOISTURE-RICH PATTERN WILL REMAIN IN PLACE FOR THE END OF THIS WEEK INTO THE START OF NEXT WEEK...INCLUDING PERIODS OF STRONG THUNDERSTORMS AND HEAVY RAIN. AN UPPER LEVEL RIDGE BUILDING OVER THE DAKOTAS AND MN/WI THRU TDA WILL SHIFT TO THE E THRU THU WHILE A LONGWAVE TROUGH DEVELOPS OVER THE NORTHWEST. SEVERAL SHORTWAVE DISTURBANCES RIDING NOT ONLY OVER TOP THE RIDGE BUT ALSO AROUND THE BASE OF THE TROUGH THU INTO FRI WILL WORK WITH AN INCOMING SFC FRONTAL SYSTEM DEVELOPING OVER THE CENTRAL-NRN PLAINS. SOLID SW FLOW WILL BRING NOT ONLY WARMER AIR /WHICH WILL RAISE H5 HEIGHTS TO ENHANCE CAPPING BUT ALSO STRONGER JETTING/ BUT ALSO MOISTURE-RICH AIR /HELPING RAISE PWATS ABOVE 1.50 INCHES AND ENHANCE INSTABILITY/...AND THE SFC FRONTAL WAVES COMBINED WITH UPPER LEVEL DISTURBANCES WILL ALLOW FOR PERIODS OF CONVECTION. THURSDAY CONTINUES TO BE HIGHLIGHTED BY SPC INVOF THE APCHG CDFNT FOR THE WRN HALF OF MN. ONCE THE CAPPING INVERSION IS LOST OVER WRN MN...STRONG MID- AND UPPER-LEVEL JETTING WITH STEEP LAPSE RATES WITHIN A HIGHLY UNSTABLE ENVIRON /INCLUDING DEWPOINTS NEAR- OVER 70 DEGREES/ WILL PROMOTE STRONG TO SEVERE TSTMS CAPABLE OF PRODUCING LARGE HAIL AND DMGG WINDS. THE REGIME THEN TRANSITIONS TO ONE OF HEAVY RAIN OVER THE WEEKEND AS THE SFC LOW PRES SYSTEM OPENS UP AND BECOMES CAUGHT UP IN THE PROLIFIC SWLY FLOW WHILE THE NW UPPER LEVEL TROUGH OPENS TO MORE OF A TROUGH THAN CUTOFF LOW. LONG PLUME OF SLY SFC FLOW WILL AID IN BRINGING MOISTURE WELL N INTO THE UPPER MISS RIVER VALLEY REGION. MODEL QPF CONTINUES TO ADVERTISE BETWEEN 3 AND 6 INCHES OF RAIN FOR THE AREA THROUGH THE WEEKEND...BUT WITH MUCH OF IT CONVECTIVE...TRYING TO PINPOINT WHERE SUCH RAINFALL EVENTS MAY OCCUR IS HIGHLY PROBLEMATIC. STILL...HAVE KEPT HIGH-END CHC POPS GOING IN THE FCST. POPS DIMINISH FOR THE START OF NEXT WEEK AS A MORE ZONAL UPPER LEVEL PATTERN DEVELOPS...KEEPING ANY ORGANIZED LOW PRES SYSTEMS AWAY FROM THE AREA. THAT SAID...SEVERAL MID- AND UPPER-LEVEL SHORTWAVE DISTURBANCES WILL STILL BE CAPABLE OF PRODUCING ISOLD TO SCATTERED CONVECTION AS THE WARM/MOIST AIR WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 610 AM CDT WED JUN 19 2013 VFR CIRRUS AND ISOLATED MID LEVEL DECK OVER WESTERN HALF OF TAF SITES SHORTLY AFTER 12Z. LOOK FOR THIS LAYER TO OVERSPREAD REMAINDER OF REGION BY ABOUT 15Z. PROXIMITY OF WARM FRONTAL BOUNDARY SHOULD BE CATALYST FOR WDLY SCT CONVECTION OVER MOST AIRPORT SITES BY MID TO LATE AFTN. LIGHT SE FLOW BECOMES MDT WITH MIXING BY 15Z ACROSS SOUTHERN MN/WESTERN WI. MUCH BETTER CHANCE FOR CONVECTION KICKS OFF KAXN AND KRWF AFT 07Z...AND OVER REMAINDER OF TAF AREA BY 10Z...AS LOW LEVEL FORCING AND JET STREAM SUPPORT INCREASES MARKEDLY. VFR CIGS AND VSBYS ANTICIPATED PRIOR TO OVERNIGHT CONVECTIVE ACTIVITY...WITH OCNL MVFR CIGS/VSBYS AS ACTIVITY WITHIN VCNTY OR OVERHEAD. KMSP... /OUTLOOK FOR KMSP/ VFR CIGS AND VSBYS THROUGH MOST OF TAF PERIOD...WITH LIGHT OCNL MODERATE SE FLOW EXPECTED. SLIGHT CHANCE FOR STRONG T-STORMS ANTICIPATED AFTER 10Z TONIGHT...IN TANDEM WITH LOW LEVEL SOUTHERLY JET STREAM. POSSIBILITY OF SHORT TERM LLWS 20/06Z-20/12Z TIME FRAME. MVFR CIGS AND VSBYS WILL BE VERY POSSIBLE ASSOCIATED WITH CONVECTION LATE. COULD BE VCSH AT KMSP UNTIL 20/20Z...UNTIL FORCING DIMINISHES. THU...VFR. CHC OF MVFR. TSRA LIKELY. SSE WINDS 10 KTS. FRI...VFR. CHC OF MVFR. TSRA LIKELY FRI NIGHT. S WINDS 10-15 KTS. SAT...VFR. CHC OF MVFR TSRA. S WINDS 5-12 KTS. SUN...VFR. CHC OF MVFR TSRA. S-SW WINDS 5-12KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...AJZ LONG TERM...JPC AVIATION...AJZ
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1036 AM CDT WED JUN 19 2013 .UPDATE... A WEAK AND STALLED FRONTAL BOUNDARY WILL BE THE MAIN FOCUS THIS AFTERNOON FOR SOME SHOWERS/THUNDERSTORM ACTIVITY. THIS BOUNDARY WILL SLOWLY DRIFT TO THE SOUTH THROUGHOUT THE DAY. WATER VAPOR ANALYSIS INDICATES A S/WV AND TROUGH AXIS MOVING THROUGH THE ARKLAMISS DELTA. THE ENHANCED SYNOPTIC LIFT AND AIDED WITH CONVERGENCE ALONG THE STALLED FRONTAL BOUNDARY WILL AID IN SHOWER/THUNDERSTORM DEVELOPMENT THIS AFTERNOON TO EVENING. WENT CLOSE TO MAV POPS AS HRRR WAS INDICATING MOST ACTIVITY ALONG AND S OF THE I-20 CORRIDOR...MAINLY IN THE SE...AND WEAKENING AFTER 00Z. WEAK LAPSE RATES AND VERTICAL TOTALS AROUND 25-26C WILL AID IN SOME THUNDERSTORM DEVELOPMENT BUT NOT EXPECTING MUCH IN THE WAY OF STRONG STORMS. TEMPS TODAY LOOK TO BE RUNNING ON TRACK AND DID NOT MODIFY HIGH TEMPS THIS AFTERNOON. ONLY MODIFIED HOURLY TEMPS/DEWPOINTS ACCORDING TO CURRENT TRENDS. ALSO MODIFIED CLOUD COVER GRIDS TO ONLY SLIGHTLY SPEED UP SOUTHWARD PROGRESSION OF CLOUD COVER. REST OF THE FORECAST IS ON TRACK. /DC/ && .AVIATION...MVFR CIG AT A FEW LOCALES WILL TREND VFR BY LATE MORNING W/VFR CONDS PERSISTING THRU THE REMAINDER OF THE DAY. NUMEROUS SHRA WILL IMPACT SE MS OVER THE NEXT FEW HRS BEFORE MORE ISOLD ACTIVITY TAKES SHAPE THIS AFTN. ELSEWHERE ISOLD SHRA WILL BE PSBL THIS MORNING DECLINING IN COVERAGE THRU THE AFTN. MVFR/IFR CIG AND PSBLY VSBY CAN BE XPCTD AT HBG/MEI AND PSBLY JAN/HKS TOMORROW MORNING 10-14Z. /BK/ && .PREV DISCUSSION... /ISSUED 340 AM CDT WED JUN 19 2013/ SHORT TERM...THE FOCUS OF THE FORECAST WILL CONTINUE TO REVOLVE AROUND PRECIP CHANCES...ESPECIALLY FOR TODAY AND THU...BUT THESE CHANCES WILL OVERALL LESS THAN WHAT THE AREA HAS SEEN THE PAST COUPLE DAYS. ONE OF THE KEY FEATURES THAT WILL INFLUENCE OUR WEATHER IS THE STALLED WEAK SFC FRONT ACROSS THE AREA. THIS BOUNDARY HAS BECOME BROAD/DIFFUSE...BUT IS GENERALLY SITUATED FROM TUP TO MLU. WHILE IT WOULD SEEM THAT AREAS ALONG AND SOUTH OF SAID BOUNDARY WOULD HAVE THE BEST PRECIP POTENTIAL TODAY...THIS NOT TRULY THE CASE. THE REASON IS THAT SOME DRIER AIR IN THE MID LEVELS IS PRESENT FOR AREAS JUST NORTH OF I-20. THIS IS IN PART TO NORTHERLY MID LEVEL FLOW DRAWING SOUTHWARD THAT DRIER AIR AS THE S/WV PASSED ACROSS THE SOUTHERN PARTS OF THE FORECAST AREA LAST EVENING. WITH ALL OF THIS...AREAS ALONG AND SOUTH OF I-20 WILL HAVE THE DEEPEST MOISTURE TO WORK WITH TODAY ALONG WITH SOME LOW LEVEL FOCUS FROM THE STALLED SFC BOUNDARY. ADDITIONALLY...WATER VAPOR IMAGERY SHOWS THE MID/UPPER TROUGH AXIS QUITE WELL AND IT IS SITUATED JUST TO OUR WEST. THIS FEATURE SHOULD ASSIST LIFT (ESP THIS MORNING) AND GENERATE PRECIP ACROSS THE SOUTHERN HALF OF THE AREA. THINKING THAT THE AIRMASS HAS BEEN WORKED OVER QUIET A BIT...OVER ALL LESS STORM COVERAGE IS EXPECTED. THUS...FOLLOWING THE 20-40% POPS FROM THE GFS SEEM VALID. WITH ANOTHER EARLY START TO ACTIVITY...WILL TREND POPS/WX DOWN FOR THE LATE AFTERNOON. LIKE YESTERDAY...TEMPS WILL BE HELD IN CHECK THANKS TO CLOUDS AND THE EARLY START TO PRECIP. GFS GUIDANCE INDICATES THIS WELL AND HAVE FOLLOWED. TONIGHT WILL BE GENERALLY QUIET WITH CLEARINGS SKIES. TEMPS WILL BE A BIT COOLER THAN WHAT WE HAVE SEE WITH UPPER 60S EXPECTED. THURSDAY WILL BE A TRICKIER FORECAST AS THE PREV MENTIONED SFC BOUNDARY WILL STILL BE IN THE GENERAL AREA BUT LIKELY SITUATED/ORIENTED IN A DIFFERENT MANNER. DEEP MOISTURE WILL BE OVERALL LOWER AREAWIDE WITH HIGHER MOISTURE CONTENT GENERALLY ACROSS THE SW/S HALF. WHAT MAKES THE FORECAST TRICKY IS THE PRESENCE OF A DISTINCT S/WV DROPPING SE. ASSOCIATED WITH THIS FEATURE WILL BE COOLER TEMPS IN THE MID LEVEL AND ALOFT. THE MID/UPPER LEVEL JET WILL ALSO BE SITUATED IN A WAY THAT SUPPORTS UPWARD MOTION. EVEN AS THESE FAVORABLE FEATURES EXIST...MODEL DATA IS NOT SHOWING MUCH DEVELOPMENT. I CAN`T ARGUE THAT THERE WILL BE LESS OVERALL POTENTIAL...BUT FEEL THAT ENOUGH INGREDIENTS WILL EXIST THAT ISOLATED STORMS WILL BE POSSIBLE DURING THE AFTERNOON. WITH THAT...HAVE INCREASED POPS FROM 10% TO 20% AND MENTIONED SLIGHT CHANCE FOR AFTERNOON ACTIVITY. AT THIS TIME...I WILL NOT MENTION ANY POSSIBILITY FOR STRONG STORMS...BUT THIS WILL HAVE TO BE MONITORED AS THE COOLER TEMPS ALOFT WILL LEAD TO BETTER LAPSE RATES AND A BIT HIGHER INSTABILITY AS SFC TEMPS WILL BE 2-4 DEGREES WARMER. /CME/ LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY...AN UPPER RIDGE WILL TRY BUILDING INTO THE WESTERN HALF OF THE FORECAST AREA FRIDAY INTO THE WEEKEND AS AN UPPER TROUGH PULLS OFF TO THE NORTHEAST AND UP THE EAST COAST. AS THIS HAPPENS...THE TROUGH WILL LEAVE BEHIND A PIECE OF ENERGY THAT`LL SET THE STAGE FOR SOME ISOLATED TO SCATTERED AFTERNOON AND EARLY EVENING SHOWERS AND STORMS OVER MAINLY EAST AND SOUTHEAST MISSISSIPPI THROUGH THE WEEKEND. RAIN CHANCES LOOK TO WANE HEADING INTO THE NEW WORK WEEK AS THE UPPER RIDGE BUILDS FURTHER EAST INTO THE CWA. OTHERWISE...LOOK FOR CONTINUED HOT AND HUMID CONDITIONS THROUGH THE FORECAST PERIOD. GUIDANCE SUGGESTED HIGHS AND LOWS LOOK REASONABLE THIS MORNING. HIGHS EACH AFTERNOON WILL RANGE IN THE LOW TO MID 90S...WHILE LOWS EACH NIGHT GENERALLY RANGE FROM THE UPPER 60S TO LOWER 70S. /19/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 89 66 91 69 / 25 9 17 6 MERIDIAN 87 64 91 68 / 27 12 15 12 VICKSBURG 88 64 91 68 / 21 7 17 4 HATTIESBURG 87 68 92 69 / 40 24 23 12 NATCHEZ 87 67 90 68 / 34 9 23 6 GREENVILLE 90 68 94 70 / 6 4 7 3 GREENWOOD 90 65 93 68 / 7 4 5 5 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ DC/BK/CME/19
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
913 AM MDT WED JUN 19 2013 .UPDATE... SEVERE THUNDERSTORMS WILL BE POSSIBLE N OF A KLVM TO KBIL LINE THIS AFTERNOON AND EVENING. IF CONVECTION INHIBITION CAN BE OVERCOME OVER SE MT...SEVERE WEATHER WILL BE POSSIBLE THERE TOO. PLENTY OF FACTORS WILL CONTRIBUTE TO LIFT OVER THE AREA THROUGH TONIGHT. DIFLUENT FLOW WAS EVIDENT ON WATER VAPOR IMAGERY THIS MORNING. UPPER LOW WAS ALSO SEEN ON IMAGERY NEGATIVELY TILTING INTO THE PACIFIC NW. A STRONG 500 MB FLOW W OF THE AREA AT 12Z WILL MOVE E DURING THE DAY BRINGING INCREASING SHEAR. SHORTWAVE ENERGY WILL ROTATE INTO THE AREA TODAY THROUGH TONIGHT...BRINGING Q-VECTOR CONVERGENCE. A LOW-LEVEL JET WILL STRENGTHEN OVER THE EASTERN ZONES TODAY AS WELL. MORE LIFT WILL BE PROVIDED BY STRONG JET DIVERGENCE OVER THE WESTERN ZONES TONIGHT. THERE WILL NOT BE A LOT OF MOISTURE TO WORK WITH THROUGH THIS EVENING AS MOISTURE TRANSPORT VECTORS SHOWED THE BEST MOISTURE BEING TRANSPORTED FROM THE CENTRAL PLAINS INTO THE NE PART OF MT. REMAINDER OF THE AREA WILL RECEIVE MOISTURE FROM WY/SE ID/UT WHERE PRECIPITABLE WATERS WERE AROUND /0.30/ INCHES WHICH WAS DRY AIR. AS FOR INSTABILITY...HIGH CAPES AND HELICITIES WILL BE E OF KBIL THIS AFTERNOON AND EVENING SO STORMS THAT DO FORM WILL NEED TO MONITORED CLOSELY FOR SEVERE POTENTIAL. STORMS THAT FORM ALONG THE NORTHERN TIER WILL BE IN A HIGH CAPE/INCREASING SHEAR ENVIRONMENT AND WILL NEED TO BE WATCHED AS WELL. THE AREAS WHERE SEVERE STORMS AND DRY THUNDERSTORMS WERE MENTIONED WERE IN GOOD SHAPE PER THE ABOVE. NOTE THAT THE 12Z HRRR HAS NOTHING DEVELOPING UNTIL 22Z THIS AFTERNOON. SEE NO NEED TO CHANGE GOING FORECAST. THE SYSTEM/S COLD FRONT WILL MOVE INTO THE WESTERN ZONES BY 00Z TONIGHT AND CROSS THE AREA OVERNIGHT. SPC SSEO FROM 00Z LAST NIGHT SHOWED ACTIVE WEATHER EXITING THE AREA BETWEEN 06-09Z TONIGHT. ONLY TEMPERATURE ADJUSTMENT WAS TO LOWER READINGS INTO THE 80S IN FAR SE MT WHERE MIXING WILL BE JUST ABOVE 850 MB. ARTHUR && .SHORT TERM...VALID FOR TDY AND THU... ...TODAY... AN APPROACHING UPPER LEVEL LOW WILL PIVOT A NEGATIVELY TILTED SHORTWAVE ACROSS WESTERN MONTANA THIS AFTERNOON. THIS WILL PUSH A SURFACE LOW...CURRENTLY POSITIONED ACROSS SOUTHEAST IDAHO...ACROSS THE FORECAST AREA INTO EASTERN MONTANA BY TONIGHT. THE ACCOMPANYING SURGE OF SOUTHWESTERLY WIND BEHIND THE LOW WILL PUSH VERY DRY AIR ACROSS THE SOUTHERN PORTIONS OF THE FORECAST AREA BY THIS AFTERNOON...WITH THE MOIST GULF MOISTURE TAP WRAPPING AROUND THE NORTHERN SIDE OF THE LOW INTO THE GGW AND TFX FORECAST AREAS. EXPECT TO SEE DEW POINTS CRASH INTO THE 30S AND 40S ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA AS MIXING BECOMES ESTABLISHED IN THE LATE MORNING. OUR NORTHERN TIER OF COUNTIES WILL REMAIN ON THE GRADIENT BETWEEN THE DRY AIR AND MUCH MORE MOIST AIR AND SHOULD RETAIN DEW POINTS IN THE 50S. THESE HIGHER DEW POINTS WILL SUPPORT THE BETTER POTENTIAL FOR CONVECTION AND EVEN SOME SEVERE WEATHER IN THE FORM OF HAIL AND STRONG WINDS. HOWEVER...FARTHER SOUTH TOWARD BILLINGS THE LCLS WILL BE ALMOST 15K FEET WITH ALL THE CAPE EXTREMELY ELEVATED. CURRENT THINKING IS THAT THE BEST CHANCE OF STRONG TO SEVERE THUNDERSTORMS WILL PROGRESS FROM THE CRAZY MOUNTAINS TO HARLOWTON TO ROUNDUP TO NORTHERN ROSEBUD COUNTY BY THIS EVENING. HOWEVER FOR THE SOUTHERN TIER OF THE FORECAST AREA...EXPECT ONLY ISOLATED DRY THUNDERSTORMS WHICH COULD PRODUCE SOME GUSTY WINDS. EXPECT THE CONVECTIVE THREAT WILL END ACROSS THE FORECAST AREA BY 03 TO 06Z AS THE THREAT SHIFTS NORTH. ...TONIGHT AND THURSDAY... THE SURFACE COLD FRONT WILL PROGRESS ACROSS THE FORECAST AREA FROM THE LATE AFTERNOON IN THE WEST TO AFTER MIDNIGHT IN THE EAST. COOLER AIR WILL PUSH IN BEHIND THE FRONT BRINGING ALLOWING TEMPERATURES TO BE COOLER THAN LAST NIGHT IN CENTRAL AND WESTERN ZONES. WINDS WILL STAY UP OVERNIGHT IN THE EAST KEEPING OVERNIGHT LOWS IN THE MID TO UPPER 50S. TEMPERATURES WILL BE COOLER TOMORROW IN THE POST FRONTAL ENVIRONMENT WITH 700MB TEMPERATURES CRASHING AROUND +13C TO DOWN TO AROUND +5C. THUS EXPECT HIGH TEMPERATURES TO STAY MAINLY IN THE 70S THURSDAY. THE UPPER LEVEL LOW WILL STILL BE POSITIONED TO OUR WEST ON THURSDAY AND A NEW SURFACE LOW WILL DEVELOP OVER NORTHERN WYOMING GOING INTO THURSDAY EVENING. THIS ALLOWS EASTERLY LOW LEVEL WINDS TO INCREASE THE MOISTURE OVER SOUTHEAST MONTANA. THIS COMBINED WITH THE INVERTED SURFACE TROUGH ACROSS EASTERN MONTANA...EXPECT TO SEE AN INCREASED CHANCE OF DEVELOPING SOME SHOWERS BY THURSDAY EVENING. CHURCH .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... SLOWING TREND OF TRANSIT OF THE UPPER LOW THROUGH THE AREA IS BRINGING INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS SATURDAY AND SUNDAY BUT HELPING MAKE LATER PERIODS DRIER. FRIDAY WILL STILL BE SEEING LOW LEVEL MOISTURE RECOVERING SO THERE IS A THREAT OF CONVECTION BUT PRECIP AMOUNTS WILL BE LIGHT. FRIDAY NIGHT THE UPPER LOW DIGS INTO SOUTHWESTERN MONTANA AND REALLY GIVES A CHANCE FOR MOISTURE TO DEEPEN ACROSS CENTRAL AND EASTERN MONTANA AT THE LOWER LEVELS DESPITE SOUTHWESTERLY FLOW ALOFT STILL TRYING TO ADVECT IN DRIER AIR. WITH STRONG DIFFLUENCE AND PLAINS MOISTURE WRAPPING BACK INTO THE YELLOWSTONE VALLEY LOOKS LIKE A GOOD CHANCE TO GET WET. SATURDAY IN PARTICULAR WILL HAVE TO BE WATCHED FOR THE STRENGTH OF STORMS WITH FAVORABLE SHEAR BUT INSTABILITY MAY BE LIMITED DUE TO COOL BOUNDARY LAYER TEMPERATURES. SUNDAY THE UPPER LOW EJECTS INTO EASTERN MONTANA AND WRAP AROUND MOISTURE CONTINUES TO BRING A THREAT OF SHOWERS AND THUNDERSTORMS TO MAINLY THE EASTERN HALF OF THE AREA. TEMPERATURES ON FRIDAY THROUGH SUNDAY COULD RUN 10 DEGREES BELOW NORMAL ESPECIALLY IF CLOUDS DOMINATE AND ENOUGH DYNAMIC COOLING OCCURS. MONDAY AND BEYOND IS DRYING AS FLOW BECOMES WESTERLY AND NEXT UPSTREAM SYSTEM IS PROGGED TO EJECT TO THE NORTH AND WEST OF MONTANA. BORSUM && .AVIATION... ISOLATED THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS BY EARLY THIS AFTERNOON WITH A FEW THUNDERSTORMS MOVING ONTO THE PLAINS WEST OF BILLINGS BY MID AFTERNOON. THE MAJORITY OF THE THUNDERSTORM ACTIVITY IS EXPECTED TO BE NORTH AND WEST OF KBIL. STRONG GUSTY WINDS WILL BE THE MAIN THREAT WITH ANY THUNDERSTORM. A COLD FRONT WILL MOVE ACROSS THE FORECAST AREA THIS EVENING INTO THE OVERNIGHT HOURS. HOOLEY && .PRELIMINARY POINT TEMP/POPS... TDY THU FRI SAT SUN MON TUE ------------------------------------------------------- BIL 093 052/077 052/072 052/069 051/078 054/082 056/082 1/T 11/B 23/T 34/T 41/B 11/B 22/T LVM 085 043/072 041/069 042/067 046/079 046/082 049/081 3/T 22/T 23/T 35/T 50/B 02/T 22/T HDN 095 053/078 052/074 050/072 050/078 052/082 052/083 1/T 11/B 32/T 34/T 41/B 11/B 22/T MLS 096 058/081 055/076 056/076 055/080 056/083 057/083 1/N 21/B 44/T 34/T 43/T 11/B 11/B 4BQ 095 054/081 055/076 054/075 053/079 054/084 055/084 1/N 11/B 44/T 34/T 52/T 11/B 22/T BHK 087 057/080 054/076 055/074 054/076 054/080 057/082 1/N 21/B 36/T 55/T 53/T 11/B 22/T SHR 090 048/078 050/073 048/073 047/076 049/081 050/082 1/T 11/B 32/T 24/T 41/B 11/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
608 AM CDT WED JUN 19 2013 .AVIATION... 12Z TAFS FOR KOFK...KOMA AND KLNK. ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN NEBRASKA THIS MORNING WITH CHANCES INCREASING LATER TODAY...ESPECIALLY OVERNIGHT. DUE TO THE APPARENT MINIMAL COVERAGE AND LOW CONFIDENCE W/RESPECT TO TIMING...NO MENTION WAS MADE AT TAFS EXPECT AT KOFK LATE TONIGHT WHEN LOW LEVEL JET MAY HAVE MORE SUCCESS IN BRINGING A BIT MORE WIDESPREAD ACTIVITY TOWARD THAT AREA. OUTSIDE OF ANY CONVECTION...VFR CONDITIONS ARE EXPECTED. CHERMOK && .PREV DISCUSSION... /ISSUED 337 AM CDT WED JUN 19 2013/ DISCUSSION... ALTHOUGH WE ARE NOT EXPECTING A CONTINUOUS PERIOD OF SHOWERS AND THUNDERSTORMS OVER THE NEXT 48 HOURS...IT REALLY IS DIFFICULT TO DISCERN ANY PERIOD IN THAT TIME THAT SHOULD NOT WARRANT AT LEAST A SLIGHT CHANCE POP. THEREFORE...WE WILL BE CARRYING A SMALL POP FOR PORTIONS OF THE CWA THROUGH THIS TIME WITH GREAT UNCERTAINTY ON TIMING/LOCATION. MODEL GUIDANCE HAS PERFORMED RATHER POORLY ON WEAK CONVECTIVE EVENTS IN THE PAST COUPLE DAYS AND SO FORECASTER CONFIDENCE REMAINS LOW. UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY SHOW A LARGE TROUGH OFF THE PACIFIC COAST WITH THE LOW PRESSURE CENTERED JUST OFF THE OREGON/WASHINGTON COASTS. OUT AHEAD OF THIS IS A WEAK RIDGE OF HIGH PRESSURE EXTENDING FROM THE SOUTHERN PLAINS INTO THE WESTERN DAKOTAS. SEVERAL WEAK IMPULSES ARE EMBEDDED WITHIN THE SOUTHWEST FLOW IN BETWEEN THE MAIN FEATURES. THE FIRST SHORTWAVE OF CONCERN IS CURRENTLY LOCATED OVER THE NEBRASKA PANHANDLE. LATEST REGIONAL RADAR MOSIAC SHOWS A CONVECTIVE COMPLEX SLOWLY DRIFTING EAST AND WEAKENING ACROSS WESTERN NEBRASKA WHILE ANOTHER MOVES SLOWLY NORTHEAST ACROSS NORTHWEST KANSAS AND WEAKENS. LATEST RAP BRINGS A HINT OF THIS ACTIVITY INTO THE FORECAST AREA THROUGHOUT THE MORNING AND AM GOING TO TWEEK POPS ACCORDINGLY. BROAD SCALE LIFT ASSOCIATED WITH THE MID LEVEL IMPULSE WILL STILL BE PRESENT INTO THE AFTERNOON AND AS INSTABILITY INCREASES WITH DAYTIME HEATING...FEEL THUNDERSTORMS HAVE A CHANCE TO CONTINUE ACROSS THE FORECAST AREA IN A BROAD LOW LEVEL WARM AIR ADVECTION REGIME. LOW LEVEL JET WILL VEER SLIGHTLY OVERNIGHT AND COULD SUSTAIN CONVECTIVE ACTIVITY...THEREFORE WILL CONTINUE A POP THROUGH THE OVERNIGHT. BY THURSDAY...THE UPPER RIDGE AXIS WILL BE DIRECTLY OVERHEAD AND EXTEND INTO THE EASTERN DAKOTAS. IN ADDITION...A SFC COLD FRONT WILL EXTEND SOUTH ACROSS THE CENTRAL DAKOTAS AND INTO NORTHWEST NEBRASKA WHICH WILL LIKELY BE THE FOCUS FOR THUNDERSTORM DEVELOPMENT. VERY STRONG INSTABILITY WILL EXIST IN OUR NORTHERN CWA HOWEVER A QUITE STOUT CAP WILL ALSO BE IN PLACE WHICH MAY PROHIBIT THE EASTWARD EXPANSION OF TSTMS. SPC HAS INCLUDED OUR NORTH IN THE SWODY2 FOR ANY MCS ACTIVITY MOVING SOUTHEAST FROM NRN PLAINS CONVECTION. THIS WILL BE AIDED BY A VEERING SOUTHWEST LOW LEVEL JET AND SO HAVE HIGHER POPS GOING IN OUR NORTH. THE AREA IS DOMINATED BY SOUTHWEST FLOW ALOFT INTO THE WEEKEND WITH THE MAIN UPPER LOW MOVING ACROSS THE PACIFIC NORTHWEST AND TOWARD THE NORTHERN PLAINS. THE MAIN SFC BOUNDARY WILL REMAIN TO OUR NORTH LEAVING THE REGION IN THE WARM SECTOR. HIGHS WILL LIKELY TOP OUT IN THE LOW 90S. AS THE UPPER LOW MOVES TOWARD THE NORTHERN PLAINS BY SUNDAY...THE SFC FRONT WILL DROP SOUTH INTO THE AREA AND BE THE POTENTIAL FOCUS FOR THUNDERSTORMS. KERN && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1037 AM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE CRUISES WEDNESDAY AND THURSDAY...BEFORE DROPPING ANCHOR IN THE WESTERN ATLANTIC TO BEGIN THE SUMMER SEASON. HIGH RIDGE ALOFT KEEPS DRY CONDITIONS THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 630 AM UPDATE... SFC FRONT ROUGHLY FROM POCAHONTAS COUNTY SW-WARD TO JUST NORTH OF BKW AT THIS TIME AND WILL CONTINUE A BIT FURTHER SOUTHWARD INTO VIRGINIA BEFORE STALLING LATER THIS MORNING. TWEAKED SKY COVER TO REFLECT QUICKER CLEARING ACROSS SE OHIO AND INTO ADJACENT WEST VIRGINIA. INGESTED RECENT OBS. OTHERWISE...NO MAJOR CHANGES. PREVIOUS DISCUSSION... AT 06Z SFC OBS INDICATE SECONDARY FRONT LOCATED ROUGHLY FROM HTS EAST/NORTHEAST TO NEAR CKB. NEAR AND AHEAD OF IT A FEW SHOWERS AND EVEN ONE THUNDERSTORM HAD REDEVELOPED EARLY THIS MORNING. THE ENHANCEMENT LIKELY DUE TO A VORT MAX...EVIDENT IN WV IMAGERY...MOVING QUICKLY ACROSS NORTH CENTRAL OHIO. ALL IN ALL EXPECT A NICE DAY FOR MOST FOLKS AS THE AFOREMENTIONED FRONT MOVES THROUGH THE AREA...UNDER PARTLY TO MOSTLY SUNNY SKIES BY THE AFTERNOON AND SEASONABLY WARM TEMPS. LARGE SCALE FORCING FOR SUBSIDENCE WILL OVERSPREAD THE FORECAST AREA FROM NW TO SE AS A 500MB S/W TROUGH PUSHES EASTWARD ACROSS AND EXITS TO THE EAST AROUND THE 18Z-21Z TIME FRAME. BY THE AFTERNOON HOURS HOWEVER...THE SFC FRONT BEGINS TO WASH OUT AND AS SFC HIGH PRESSURE REBUILDS TO THE EAST. MODELS IN GOOD AGREEMENT WITH GOOD SFC CONVERGENCE ALONG THE EASTERN HIGH TERRAIN PEAKS AS SFC FLOW ON THE EAST SIDE RETURNS QUICKLY TO THE EAST/SOUTHEAST...WHILE FLOW ON THE WINDWARD SIDE REMAINS NORTH/NORTHWEST. SOME QUESTION AND DOUBT AS TO THE DEPTH OF MOISTURE BEING DEPICTED ON LATEST NAM12 SOUNDINGS HOWEVER...AND LATEST RUC13 SOUNDINGS ARE INDEED MUCH DRYER IN LOWER LEVELS. EVEN WITH THE MORE SATURATED NAM12...PWATS STILL ONLY PROGGED AROUND 0.8IN-0.9IN WITH VERY DRY AIR ALOFT WHICH WOULD SERVE TO LIMIT COVERAGE. PREV FCST HAD A GOOD HANDLE ON THIS AND WILL CONTINUE SLIGHT CHANCE TO LOW CHANCE POPS ESSENTIALLY FROM THE HIGHEST PEAKS AND POINTS SOUTH AND EAST...WITH STORM MOTION TO THE SOUTHEAST. DID INSERT A SLIGHT THUNDER MENTION WITH DECENT INSTABILITY IN THAT AREA. AS SUCH...KEPT CLOUD COVER HIGHER IN THE EASTERN HIGH COUNTRY AS WELL. ALSO NUDGED MAX TEMPS UP AN ADDITIONAL DEGREE OR TWO FOR MOST LOCATIONS PER LATEST PROGGED 925MB AND 850MB TEMPS WITH MOS GUIDANCE SUPPORTING...ALTHOUGH DID KEEP MAX TEMPS IN THE MOUNTAINS JUST A BIT LOWER WITH MORE CLOUDS AND SOME AFTERNOON PRECIP POTENTIAL. OVERNIGHT FORECAST REMAINS VIRTUALLY UNCHANGED FROM PREV SHIFT THINKING...WITH MINS IN THE MID AND UPPER 50S LOWLANDS. WILL HAVE PRECIP ENDING AT 00Z THU IN THE MOUNTAINS. AREAS OF FOG ARE A GOOD BET ONCE AGAIN IN THE LOWLANDS UNDER A MOSTLY CLEAR SKY AND NEAR-CALM WINDS...ALTHOUGH SOME LOWER DEWPOINTS ACROSS SE OHIO AND MORE CLOUD COVER IN THE MOUNTAINS MAY LIMIT COVERAGE IN THOSE AREAS. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... SFC HIGH PRESSURE MOVE OFF SHORE THE NORTHEAST COAST LATE THURSDAY LOSING ITS INFLUENCE WEST OF THE APPALACHIANS. HOWEVER...ABUNDANT LOW LEVEL MOISTURE AND ELEVATED HEAT SOURCES COULD PRODUCE ISOLATED AFTERNOON SHOWERS OR STORMS OVER HIGHER ELEVATIONS THROUGH THE WEEKEND. A MID LEVEL RIDGE MOVES OVERHEAD SATURDAY PROVIDING SOME SUBSIDENCE AND CLEAR SKIES. AFTERNOON CU WILL BE COMMON JUST TO DISSIPATE AFTER SUNSET. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... SURFACE HIGH PRESSURE WILL REMAIN CENTERED ACROSS THE SOUTHEAST STATES...WITH A RIDGE EXTENDING NORTH INTO WEST VIRGINIA. SOUTHERLY WINDS WILL RESULT IN DEW POINTS INCREASING TO THE UPPER 60S AND LOWER 70S. AS A RESULT...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM WILL BE A POSSIBILITY...MAINLY DURING THE AFTERNOON AND EVENING HOURS. AN UPPER LEVEL TROF AND AN ASSOCIATED COLD FRONT WILL APPROACH FROM THE WEST LATE IN THE PERIOD...RESULTING IN BETTER CHANCES FOR SHOWERS AND STORMS. THE BEST CHANCE OF GETTING WET WILL CONTINUE TO BE DURING THE AFTERNOON AND EVENING HOURS. EXPECT DAYTIME TEMPERATURES TO GENERALLY BE 5 OR MORE DEGREES ABOVE NORMAL DURING THE PERIOD. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... 12Z WEDNESDAY THROUGH 12Z THURSDAY... ONCE EARLY MORNING FOG AND LOW STRATUS SCATTER/LIFT...VFR CONDITIONS WILL PREVAIL THROUGH THE REMAINDER OF THE DAY AND MUCH OF THE EVENING. HIGH PRESSURE OVERHEAD WILL RESULT IN LIGHT NORTH/NORTHEAST WINDS TODAY. A FEW SHOWERS AND PERHAPS A THUNDERSTORM ARE POSSIBLE OVER THE EASTERN HIGH TERRAIN...WHICH COULD IMPACT EKN. NEAR-CALM WINDS AND MOSTLY CLEAR SKIES WILL RESULT IN FOG AND REDUCED VSBYS ONCE AGAIN BY AND AFTER 03Z MAINLY FOR LOWLAND WEST VIRGINIA LOCATIONS. DRIER AIR ACROSS SE OHIO AND MORE OVERNIGHT CLOUD COVER MAY HELP TO MITIGATE FOG IN THESE AREAS. CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE...MEDIUM. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z THURSDAY... FORECAST CONFIDENCE: TIMING OF FLIGHT CONDITIONS IMPROVEMENT THIS MORNING MAY VARY. ONSET...COVERAGE...AND DENSITY OF REDUCED VIS AND/OR LOW STRATUS AFTER 06Z THU MAY VARY AS WELL. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21 CRW CONSISTENCY H M H H H H H H H H H H HTS CONSISTENCY M H H H H H H H H H H H BKW CONSISTENCY M M M H H H H H H H H H EKN CONSISTENCY H M M H H H H H H H H H PKB CONSISTENCY M H H H H H H H H H H H CKB CONSISTENCY H M H H H H H H H H H H AFTER 12Z THURSDAY... IFR OR WORSE FG DEVELOPING WED NT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/50 NEAR TERM...50 SHORT TERM...ARJ LONG TERM...JSH AVIATION...50
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
649 AM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE CRUISES WEDNESDAY AND THURSDAY...BEFORE DROPPING ANCHOR IN THE WESTERN ATLANTIC TO BEGIN THE SUMMER SEASON. HIGH RIDGE ALOFT KEEPS DRY CONDITIONS THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 630 AM UPDATE... SFC FRONT ROUGHLY FROM POCAHONTAS COUNTY SW-WARD TO JUST NORTH OF BKW AT THIS TIME AND WILL CONTINUE A BIT FURTHER SOUTHWARD INTO VIRGINIA BEFORE STALLING LATER THIS MORNING. TWEAKED SKY COVER TO REFLECT QUICKER CLEARING ACROSS SE OHIO AND INTO ADJACENT WEST VIRGINIA. INGESTED RECENT OBS. OTHERWISE...NO MAJOR CHANGES. PREVIOUS DISCUSSION... AT 06Z SFC OBS INDICATE SECONDARY FRONT LOCATED ROUGHLY FROM HTS EAST/NORTHEAST TO NEAR CKB. NEAR AND AHEAD OF IT A FEW SHOWERS AND EVEN ONE THUNDERSTORM HAD REDEVELOPED EARLY THIS MORNING. THE ENHANCEMENT LIKELY DUE TO A VORT MAX...EVIDENT IN WV IMAGERY...MOVING QUICKLY ACROSS NORTH CENTRAL OHIO. ALL IN ALL EXPECT A NICE DAY FOR MOST FOLKS AS THE AFOREMENTIONED FRONT MOVES THROUGH THE AREA...UNDER PARTLY TO MOSTLY SUNNY SKIES BY THE AFTERNOON AND SEASONABLY WARM TEMPS. LARGE SCALE FORCING FOR SUBSIDENCE WILL OVERSPREAD THE FORECAST AREA FROM NW TO SE AS A 500MB S/W TROUGH PUSHES EASTWARD ACROSS AND EXITS TO THE EAST AROUND THE 18Z-21Z TIME FRAME. BY THE AFTERNOON HOURS HOWEVER...THE SFC FRONT BEGINS TO WASH OUT AND AS SFC HIGH PRESSURE REBUILDS TO THE EAST. MODELS IN GOOD AGREEMENT WITH GOOD SFC CONVERGENCE ALONG THE EASTERN HIGH TERRAIN PEAKS AS SFC FLOW ON THE EAST SIDE RETURNS QUICKLY TO THE EAST/SOUTHEAST...WHILE FLOW ON THE WINDWARD SIDE REMAINS NORTH/NORTHWEST. SOME QUESTION AND DOUBT AS TO THE DEPTH OF MOISTURE BEING DEPICTED ON LATEST NAM12 SOUNDINGS HOWEVER...AND LATEST RUC13 SOUNDINGS ARE INDEED MUCH DRYER IN LOWER LEVELS. EVEN WITH THE MORE SATURATED NAM12...PWATS STILL ONLY PROGGED AROUND 0.8IN-0.9IN WITH VERY DRY AIR ALOFT WHICH WOULD SERVE TO LIMIT COVERAGE. PREV FCST HAD A GOOD HANDLE ON THIS AND WILL CONTINUE SLIGHT CHANCE TO LOW CHANCE POPS ESSENTIALLY FROM THE HIGHEST PEAKS AND POINTS SOUTH AND EAST...WITH STORM MOTION TO THE SOUTHEAST. DID INSERT A SLIGHT THUNDER MENTION WITH DECENT INSTABILITY IN THAT AREA. AS SUCH...KEPT CLOUD COVER HIGHER IN THE EASTERN HIGH COUNTRY AS WELL. ALSO NUDGED MAX TEMPS UP AN ADDITIONAL DEGREE OR TWO FOR MOST LOCATIONS PER LATEST PROGGED 925MB AND 850MB TEMPS WITH MOS GUIDANCE SUPPORTING...ALTHOUGH DID KEEP MAX TEMPS IN THE MOUNTAINS JUST A BIT LOWER WITH MORE CLOUDS AND SOME AFTERNOON PRECIP POTENTIAL. OVERNIGHT FORECAST REMAINS VIRTUALLY UNCHANGED FROM PREV SHIFT THINKING...WITH MINS IN THE MID AND UPPER 50S LOWLANDS. WILL HAVE PRECIP ENDING AT 00Z THU IN THE MOUNTAINS. AREAS OF FOG ARE A GOOD BET ONCE AGAIN IN THE LOWLANDS UNDER A MOSTLY CLEAR SKY AND NEAR-CALM WINDS...ALTHOUGH SOME LOWER DEWPOINTS ACROSS SE OHIO AND MORE CLOUD COVER IN THE MOUNTAINS MAY LIMIT COVERAGE IN THOSE AREAS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... SFC HIGH PRESSURE MOVE OFF SHORE THE NORTHEAST COAST LATE THURSDAY LOSING ITS INFLUENCE WEST OF THE APPALACHIANS. HOWEVER...ABUNDANT LOW LEVEL MOISTURE AND ELEVATED HEAT SOURCES COULD PRODUCE ISOLATED AFTERNOON SHOWERS OR STORMS OVER HIGHER ELEVATIONS THROUGH THE WEEKEND. A MID LEVEL RIDGE MOVES OVERHEAD SATURDAY PROVIDING SOME SUBSIDENCE AND CLEAR SKIES. AFTERNOON CU WILL BE COMMON JUST TO DISSIPATE AFTER SUNSET. && .LONG TERM /SATURDAY THROUGH TUESDAY/... RIDGING WILL CONTINUE TO STRENGTHEN THROUGH THE WEEKEND INCREASING HIGH TEMPERATURES INTO AT LEAST THE THE UPPER 80S. WITH A CONTINUED MOISTURE TAP DEW POINTS WILL ALSO INCREASE INTO THE UPPER 60S TO AROUND 70. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM WILL BE A POSSIBILITY MOST EVERY AFTERNOON AND EVENING. ABOVE NORMAL TEMPERATURES AND MUGGY CONDITIONS LOOK LIKELY TO CONTINUE INTO THE FIRST HALF OF NEXT WEEK AS THE BROAD UPPER LEVEL RIDGING OVER THE EASTERN HALF OF THE US CONTINUES. WILL BE LOOKING FOR A DRIER PATTERN TO SETTLE IN THRU LATE WEEK AND AT LEAST FIRST HALF OF WEEKEND. EXCEPTION IS THE MTNS WHERE A FEW SHRA/TSRA POSSIBLE EACH AFTN AS A LEE SIDE TROF SETS UP IN CONJUNCTION WITH LLVL SE FLOW AND DIFF HEATING. A S/W TROF WILL TRY TO BEAT DOWN UPR RIDGE JUST AS IT TRIES TO BUILD E INTO AREA LATE SUNDAY INTO MONDAY. HAVE CARRIED SOME CHC POPS WITH THIS AT THIS DISTANCE. TEMPS WARM UP TO 2 TO 4 DEGREES ABV NORMAL...ESPECIALLY AT NIGHT AT THE MUGGIES BEGIN TO TAKE OVER. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... 12Z WEDNESDAY THROUGH 12Z THURSDAY... ONCE EARLY MORNING FOG AND LOW STRATUS SCATTER/LIFT...VFR CONDITIONS WILL PREVAIL THROUGH THE REMAINDER OF THE DAY AND MUCH OF THE EVENING. HIGH PRESSURE OVERHEAD WILL RESULT IN LIGHT NORTH/NORTHEAST WINDS TODAY. A FEW SHOWERS AND PERHAPS A THUNDERSTORM ARE POSSIBLE OVER THE EASTERN HIGH TERRAIN...WHICH COULD IMPACT EKN. NEAR-CALM WINDS AND MOSTLY CLEAR SKIES WILL RESULT IN FOG AND REDUCED VSBYS ONCE AGAIN BY AND AFTER 03Z MAINLY FOR LOWLAND WEST VIRGINIA LOCATIONS. DRIER AIR ACROSS SE OHIO AND MORE OVERNIGHT CLOUD COVER MAY HELP TO MITIGATE FOG IN THESE AREAS. CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE...MEDIUM. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z THURSDAY... FORECAST CONFIDENCE: TIMING OF FLIGHT CONDITIONS IMPROVEMENT THIS MORNING MAY VARY. ONSET...COVERAGE...AND DENSITY OF REDUCED VIS AND/OR LOW STRATUS AFTER 06Z THU MAY VARY AS WELL. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18 CRW CONSISTENCY L L L M M H H H H H H H HTS CONSISTENCY L L L M H H H H H H H H BKW CONSISTENCY L L L M M M H H H H H H EKN CONSISTENCY L L L H M M H H H H H H PKB CONSISTENCY L L L M H H H H H H H H CKB CONSISTENCY L L M M M H H H H H H H AFTER 12Z THURSDAY... IFR OR WORSE FG DEVELOPING WED NT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/50 NEAR TERM...50 SHORT TERM...ARJ LONG TERM...JR AVIATION...50
AREA FORECAST DISCUSSION
NWS TULSA OK
1034 AM CDT WED JUN 19 2013 .DISCUSSION... THUNDERSTORM COMPLEX CONTINUES TO DIVE SOUTH ACROSS TX PANHANDLE THIS MORNING WITH SOME ASSOCIATED ANVIL CIRRUS SPREADING INTO FAR WESTERN REACHES OF THE FORECAST AREA. IN ADDITION A RELATIVE MOIST AXIS FROM ARKLATEX INTO NC OK ASSOCIATED WITH LOWER CLOUDS AND WHILE AN ISOLATED STORM OR TWO MAY DEVELOP IN THIS AREA...FEEL THAT WITH RISING MID LEVEL HEIGHTS THE OVERALL COVERAGE/PROB TOO LOW TO INCLUDE IN FORECAST. THIS MAY BECOME FOCUS FOR OVERNIGHT STORM COMPLEX DEVELOPING OVER CENTRAL PLAINS WHICH WILL HAVE A HIGHER THREAT OF MOVING INTO EASTERN OK BY EARLY THU MORNING HOWEVER. OVERALL FORECAST APPEARS ON TRACK AND WILL MAKE UPDATES FOR LESS CLOUD COVER ACROSS EASTERN AREAS AND TO INCORPORATE HOURLY TRENDS. && .PREV DISCUSSION... /ISSUED 617 AM CDT WED JUN 19 2013/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. THUNDERSTORM CHANCES APPEAR TOO LOW TO MENTION AT NE OK TAF SITES AT THIS TIME. PREV DISCUSSION... /ISSUED 303 AM CDT WED JUN 19 2013/ DISCUSSION... A RIDGE OF HIGH PRESSURE ALOFT WILL BEGIN TO NUDGE INTO THE AREA FROM THE SOUTHWEST TODAY. BEFORE WE GET INTO SOMETHING OF A DRY PERIOD...THE AREA WILL HAVE TO CONTEND WITH A COUPLE OF THUNDERSTORM COMPLEXES. THIS MORNING THERE IS THUNDERSTORM COMPLEX THAT EXTENDS FROM SOUTHWEST KANSAS INTO THE TEXAS PANHANDLE. THE LATEST HRRR SHOWS THIS COMPLEX MOVING INTO CENTRAL OKLAHOMA THIS MORNING AS IT DECAYS. HAVE LEFT POPS OUT OF THE FORECAST FOR TODAY BUT NOT FEELING OVERLY CONFIDENT ABOUT THIS DECISION. COULD SEE SOME REDEVELOPMENT ON THE OUTFLOW BOUNDARY CREATED BY THIS COMPLEX THIS AFTERNOON. ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP ACROSS WESTERN KANSAS AGAIN THIS AFTERNOON/EVENING AND MAKE A RUN AT NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS LATE TONIGHT INTO THURSDAY. DO HAVE POPS IN THE FORECAST TO ACCOUNT FOR THIS FEATURE AS THE MODELS HAVE BEEN CONSISTENTLY SHOWING THIS FOR SEVERAL RUNS. THE UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE AREA THROUGH THE WEEKEND. THERE ARE SOME SIGNS THAT THERE MAY BE ENOUGH WEAKNESS IN THE RIDGE THAT SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE SATURDAY AND SUNDAY AFTERNOONS IN THE FAVORED TERRAIN AREAS OF SOUTHEAST OKLAHOMA INTO NORTHWEST ARKANSAS. && .PRELIMINARY POINT TEMPS/POPS... TUL 90 71 90 74 / 10 10 20 10 FSM 90 68 92 71 / 10 10 10 0 MLC 89 70 91 73 / 0 0 10 10 BVO 88 69 88 72 / 10 20 30 10 FYV 86 64 87 68 / 10 10 10 0 BYV 87 65 88 68 / 10 10 10 10 MKO 88 69 89 72 / 10 10 20 10 MIO 89 68 88 71 / 10 20 30 10 F10 88 70 90 73 / 10 10 10 10 HHW 89 70 92 72 / 0 0 10 10 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...14 LONG TERM....07
AREA FORECAST DISCUSSION
NWS NORMAN OK
652 AM CDT WED JUN 19 2013 .DISCUSSION... 12Z AVIATION DISCUSSION FOLLOWS BELOW... && .AVIATION... THUNDERSTORMS CONTINUE TO MOVE S/SE ACROSS THE TEXAS PANHANDLE AND FAR NORTHWESTERN OKLAHOMA THIS MORNING. THIS ACTIVITY WILL CONTINUE TO IMPACT KWWR AND KGAG THROUGH MID TO LATE MORNING. THIS ACTIVITY WILL SLOWLY DISSIPATE THROUGH NOON. THUNDERSTORM CHANCES WILL THEN INCREASE THROUGH THE AFTERNOON AND EVENING ACROSS NORTHERN OKLAHOMA. LOW CONFIDENCE ON TIMING AND LOCATION... THEREFORE...HAVE LEFT OUT A MENTION IN THE KWWR...KGAG...AND KPNC TAFS. THERE REMAINS A CHANCE OF MVFR STRATUS ACROSS THE SOUTHERN PORTIONS OF OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTERNOON...BUT CONFIDENCE REMAINS LOW...SO KEPT CEILINGS AT VFR AT THE MOMENT. WINDS WILL REMAIN OUT OF THE SOUTH...PICKING UP THROUGH NOON...WITH AFTERNOON GUSTS 20 TO 25 KTS AT TIMES. JTK && .PREV DISCUSSION... /ISSUED 347 AM CDT WED JUN 19 2013/ DISCUSSION... CURRENTLY...A WEAK MCS CONTINUES TO MOVE EASTWARD ACROSS SRN KS AND NWRN OK. THIS AREA OF CONVECTION REMAINS FOCUSED ALONG A LOW- LEVEL MOISTURE/THETA E AXIS POSITIONED ALONG/NEAR THE WRN KS/OK BORDER. OVERALL...MESOSCALE GUIDANCE HAS HAD A DIFFICULT GO THIS MORNING IN THE TRACK AND INTENSITY OF THESE STORMS. CURRENT THOUGHTS LEAN TOWARD THE MCS WEAKENING OVER THE NEXT FEW HOURS AS IT CONTINUES TO TRACK EASTWARD. CONDITIONS ARE LESS FAVORABLE FOR MCS MAINTENANCE ACROSS NRN AND CENTRAL OK...WHERE THE MOISTURE PROFILE IS LESS FAVORABLE AND MID-LEVEL LAPSE RATES WEAKEN CONSIDERABLY. THERE IS DECENT DEEP LAYER SHEAR...30-40KTS SPREAD INTO CENTRAL OK...BUT MUCAPES REMAIN LOW FOR MCS SUPPORT...700 TO 1000 J/KG. OVERALL...THE NEXT 12 TO 24 HOURS WILL POSE A FAIRLY DECENT CHALLENGE FORECASTWISE. THE RECENT 06Z RUN OF THE HRRR REVISES ITS PREVIOUS FORECAST...WITH CONVECTION DEVELOPING BEHIND THE MAIN LINE AND SURGING SOUTHWARD THROUGH THE TX PANHANDLE THROUGH THE MORNING. CURRENT RADAR TRENDS SUGGEST THIS MIGHT BE A POSSIBLE SCENARIO...AS NEW CONVECTION HAS STARTED TO DEVELOP OVER THE PAST HOUR...SINCE 230 AM...ACROSS SERN CO AND THE OK PANHANDLE. FOR THE MOMENT...WILL CONTINUE WITH CHANCE POPS ACROSS NWRN OK THROUGH THE MORNING HOURS. FOR THIS AFTERNOON...THE SHALLOW 500MB RIDGE WILL CONTINUE TO SHIFT/TILT EASTWARD ACROSS THE SRN PLAINS...WHILE ANOTHER LOW AMPLITUDE SHORTWAVE TRAVERSES THE REGION. WITH UPPER LEVEL SUPPORT...AND THE PAC NW TROUGH DIGGING EASTWARD...A STOUT SFC TROUGH/FRONT WILL EXTEND THE LENGTH OF THE FRONT RANGE INTO THE CENTRAL HIGH PLAINS. THIS COULD RESULT IN SOME WEAK SCATTERED CONVECTION LATER THIS AFTERNOON AND OVERNIGHT ACROSS NRN OK...PRIMARILY WELL NORTH OF THE I-40 AND I-44 CORRIDORS. EXPECT COVERAGE TO BE LIMITED WITH THIS SYSTEM...WITH MOST LOCATIONS LIKELY REMAINING DRY AFTER THIS MORNING. FOR THE REMAINDER OF THE WEEK...UPPER LEVEL RIDGING WILL TAKE HOLD...WITH SOUTH/SOUTHWEST FLOW SETTING UP SLOWLY THROUGH THE WEEKEND. TEMPERATURES WILL WARM BACK UP...WITH AFTERNOON HIGHS WELL INTO THE 90S...APPROACHING THE 100S ACROSS SWRN OK AND WRN N TX. THERE COULD BE A FEW ISOLATED SHOWERS ACROSS FAR NWRN OK SUNDAY AS THE WRN TROUGH INTENSIFIES AND A SFC FRONT APPROACHES THE REGION...BUT AT THE MOMENT...EXPECT THE GOOD MAJORITY OF THE AREA TO REMAIN DRY THROUGH THE WEEKEND. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 85 69 89 71 / 10 10 10 0 HOBART OK 90 70 96 72 / 30 10 10 10 WICHITA FALLS TX 90 72 95 73 / 10 10 0 0 GAGE OK 87 69 96 73 / 70 20 10 10 PONCA CITY OK 85 69 88 72 / 30 30 30 10 DURANT OK 88 71 91 72 / 10 10 10 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 11/04/04
AREA FORECAST DISCUSSION
NWS TULSA OK
617 AM CDT WED JUN 19 2013 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. THUNDERSTORM CHANCES APPEAR TOO LOW TO MENTION AT NE OK TAF SITES AT THIS TIME. && .PREV DISCUSSION... /ISSUED 303 AM CDT WED JUN 19 2013/ DISCUSSION... A RIDGE OF HIGH PRESSURE ALOFT WILL BEGIN TO NUDGE INTO THE AREA FROM THE SOUTHWEST TODAY. BEFORE WE GET INTO SOMETHING OF A DRY PERIOD...THE AREA WILL HAVE TO CONTEND WITH A COUPLE OF THUNDERSTORM COMPLEXES. THIS MORNING THERE IS THUNDERSTORM COMPLEX THAT EXTENDS FROM SOUTHWEST KANSAS INTO THE TEXAS PANHANDLE. THE LATEST HRRR SHOWS THIS COMPLEX MOVING INTO CENTRAL OKLAHOMA THIS MORNING AS IT DECAYS. HAVE LEFT POPS OUT OF THE FORECAST FOR TODAY BUT NOT FEELING OVERLY CONFIDENT ABOUT THIS DECISION. COULD SEE SOME REDEVELOPMENT ON THE OUTFLOW BOUNDARY CREATED BY THIS COMPLEX THIS AFTERNOON. ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP ACROSS WESTERN KANSAS AGAIN THIS AFTERNOON/EVENING AND MAKE A RUN AT NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS LATE TONIGHT INTO THURSDAY. DO HAVE POPS IN THE FORECAST TO ACCOUNT FOR THIS FEATURE AS THE MODELS HAVE BEEN CONSISTENTLY SHOWING THIS FOR SEVERAL RUNS. THE UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE AREA THROUGH THE WEEKEND. THERE ARE SOME SIGNS THAT THERE MAY BE ENOUGH WEAKNESS IN THE RIDGE THAT SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE SATURDAY AND SUNDAY AFTERNOONS IN THE FAVORED TERRAIN AREAS OF SOUTHEAST OKLAHOMA INTO NORTHWEST ARKANSAS. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...12
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
659 AM CDT WED JUN 19 2013 .AVIATION... /12Z TAFS/ MVFR CONDS PREVAIL OVER A GOOD PORTION OF NORTH TEXAS WITH VIS GENERALLY AROUND 5SM. THERE ARE SOME AREAS OF DENSE FOG PRIMARILY IN THE LOWER VALLEYS BUT THIS SHOULD STAY OUT OF THE MAJOR AIRPORTS THROUGH MID MORNING. WILL PREVAIL VFR CONDS IN THE METROPLEX...ALTHOUGH AN AMD OR TWO MAY BE NEEDED IF VIS DROPS FURTHER THAN ANTICIPATED. A COMPLEX OF THUNDERSTORMS CONTINUES TO MOVE SOUTHEAST ACROSS WESTERN OKLAHOMA. THESE STORMS ARE LIKELY TO WEAKEN IN INTENSITY AS THEY APPROACH SO NO MENTION OF PRECIP IN THE CURRENT FORECAST. SOUTH WINDS AROUND 10KT EXPECTED THROUGH THE PERIOD. DUNN && .PREV DISCUSSION... /ISSUED 318 AM CDT WED JUN 19 2013/ THE ONLY MAJOR FORECASTING CHALLENGE WITH THIS PACKAGE WILL BE PATCHY FOG IN THE EASTERN ZONES THIS MORNING AND THUNDERSTORM CHANCES TODAY. LIGHT WIND AND DAMP GROUND ACROSS EAST TEXAS AND THE EASTERN PORTIONS OF NORTH TEXAS WILL RESULT IN PATCHY FOG THROUGH MID MORNING TODAY. IT APPEARS THAT MOST OF THE DENSE FOG SHOULD BE IN EAST TEXAS BUT A FEW NORTH TEXAS LOCATIONS MAY BRIEFLY FALL TO 1/2 MILE VISIBILITY. BY 11 AM...ANY FOG THAT DID DEVELOP WILL HAVE DISSIPATED. A COMPLEX OF STORMS...CURRENTLY ACROSS WESTERN OKLAHOMA AND THE PANHANDLE...WILL CONTINUE MOVING SOUTHEAST THROUGH THE EARLY MORNING HOURS. CLOUD TOPS IN THE SOUTHERN PORTION OF THE COMPLEX HAVE BEEN WARMING OVER THE PAST COUPLE OF HOURS AND THIS TREND WILL LIKELY CONTINUE. THE HRRR SEEMS TO HAVE THE MOST REASONABLE SOLUTION OF ALL MODELS BASED ON RADAR TRENDS OVER THE LAST FEW HOURS SO WILL FOLLOW IT FAIRLY CLOSELY. THEREFORE...EXPECT MOST OF THE WEST TEXAS ACTIVITY TO DISSIPATE BEFORE REACHING THE NORTHWEST ZONES AROUND MID MORNING...BUT WILL LEAVE 20 POPS IN TO ACCOUNT FOR ANY SHOWER OR STORM THAT MANAGES TO HOLD TOGETHER. BY THIS AFTERNOON...A FEW SHOWERS OR STORMS MAY DEVELOP ACROSS THE REGION AS TEMPERATURES WARM INTO THE 90S AND SOME LEFT OVER BOUNDARIES PROVIDE A FOCUS FOR LIFT. ANY STORMS THAT DO DEVELOP SHOULD BE DISORGANIZED PULSE STORMS DUE TO THE WEAK SHEARED AND WEAK FLOW ENVIRONMENT EXPECTED. ANY SHOWERS OR STORMS THAT DO DEVELOP THIS AFTERNOON WILL DISSIPATE WITH THE LOSS OF SURFACE HEATING AND INCREASING LARGE SCALE SUBSIDENCE FROM A BUILDING UPPER LEVEL RIDGE. THE UPPER RIDGE WILL BECOME THE DOMINANT WEATHER FEATURE ACROSS THE REGION THURSDAY THROUGH EARLY NEXT WEEK. THE GOOD NEWS IS THAT THE RIDGE WILL NEVER BECOME EXTREMELY STRONG AND AS A RESULT AFTERNOON HIGH TEMPERATURES SHOULD NOT BE TOO MUCH WARMER THAN SEASONAL NORMALS. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK GENERALLY IN THE LOWER AND MIDDLE 90S AND LOWS MOSTLY IN THE 70S. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 94 74 95 75 96 / 20 10 0 0 0 WACO, TX 94 72 94 73 95 / 20 10 0 0 0 PARIS, TX 91 70 92 71 94 / 20 10 5 0 5 DENTON, TX 94 71 95 72 96 / 20 10 0 0 0 MCKINNEY, TX 91 69 92 70 94 / 20 10 5 0 0 DALLAS, TX 94 75 94 76 96 / 20 10 0 0 0 TERRELL, TX 92 71 93 72 94 / 20 10 5 0 5 CORSICANA, TX 92 72 93 73 94 / 20 10 5 0 0 TEMPLE, TX 93 71 93 72 94 / 20 10 0 0 0 MINERAL WELLS, TX 93 70 94 70 96 / 20 5 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
312 PM MDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 311 PM MDT WED JUN 19 2013 ..POSSIBLE ISOLATED SEVERE TONIGHT...CRITICAL FIRE WEATHER CONDITIONS THURSDAY... MAIN CONCERN IN THE SHORT TERM IS THE POTENTIAL FOR THUNDERSTORMS...POSSIBLY SEVERE...ALONG AND EAST OF THE DRY LINE THIS AFTERNOON AND EVENING. CURRENT SPC MESO ANALYSIS SHOWS 3 TO 4 THOUSAND J/KG OF SBCAPE AND 40KT 0-6KM BULK SHEAR ACROSS THE EASTERN PLAINS WITH LITTLE CIN. THE LATEST HRRR AND RAP TRY TO INITIATE A FEW CELLS IN THIS AREA BETWEEN 22Z AND 01Z TONIGHT. ANY STORM THAT IS ABLE TO INITIATE WILL HAVE A GOOD CHANCE OF PRODUCING LARGE HAIL. THE LATEST HRRR AND RAP ALSO PUSH THE DRYLINE SLIGHTLY FARTHER WEST INTO EXTREME EASTERN PUEBLO AND EL PASO COUNTIES AS WELL AS CENTRAL LAS ANIMAS COUNTY. I HAVE INCREASED POPS TO ISOLATED IN THESE AREAS. OVER THE REST OF THE REGION...DEWPOINTS WERE QUICK TO DROP WEST OF THE INTERSTATE INTO THE SINGLE DIGITS THIS MORNING...AND ARE SLOWLY DROPPING ALONG THE I-25 CORRIDOR AS WINDS CONTINUE TO INCREASE IN THESE AREAS. THE CURRENT RED FLAG WARNING LOOKS GOOD AND WILL LEAVE IT INTACT. THURSDAY... THE FORECAST AREA WILL REMAIN BETWEEN A QUASISTATIONARY CUT OFF LOW CENTERED OVER IDAHO AND A BROAD RIDGE OF HIGH PRESSURE CENTERED OVER TEXAS. THE RESULTING SOUTHWEST FLOW WILL RESULT IN CRITICAL FIRE WEATHER CONDITIONS ACROSS THE I-25 CORRIDOR AND AREAS WESTWARD. GUSTY WINDS...LOW DEWPOINTS...AND DRY FUELS WILL PROMOTE EXTREME FIRE GROWTH IN THESE AREAS. A RED FLAG WARNING HAS BEEN ISSUED BEGINNING AT 11AM FOR THESE AREA. THE NAM12/GFS INDICATE THE DRYLINE WILL STILL BE IN SOUTHEASTERN COLORADO THURSDAY AFTERNOON WITH ISOLATED THUNDERSTORMS POSSIBLE IN BACA COUNTY. IF THE DRYLINE SETS UP FARTHER WESTWARD THAN CURRENTLY INDICATED...ADDITIONAL COUNTIES WILL NEED TO BE WATCHED FOR STORM INITIATION LATE THURSDAY AFTERNOON. -PJC .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 311 PM MDT WED JUN 19 2013 ...CRITICAL FIRE WEATHER CONDITIONS CONTINUE THROUGH THE WEEKEND INTO EARLY NEXT WEEK... SOUTHWEST FLOW WILL REMAIN OVER THE REGION THROUGH THE WEEKEND WITH A REPEAT PERFORMANCE OF CRITICAL FIRE WEATHER CONDITIONS POSSIBLE AGAIN FOR FRIDAY. THIS LOOKS MOST LIKELY TO OCCUR ACROSS THE MOUNTAINS AND VALLEYS AND SOUTHERN I-25 CORRIDOR. IT GETS A LITTLE TRICKIER FOR NORTHERN PORTIONS OF THE I-25 CORRIDOR...MAINLY PUEBLO...EL PASO...AND TELLER COUNTIES...WITH WIND GUSTS POSSIBLY COMING UP JUST SHY OF 25 MPH FOR THE REQUIRED 3 HOUR WINDOW. HOWEVER WINDS LOOK A LITTLE STRONGER ON THE GFS SO WILL GO AHEAD AND INCLUDE THESE AREAS IN THE FIRE WEATHER WATCH. WITH TEMPERATURES PUSHING 100 ACROSS THE PLAINS...WITH GENERALLY 60S/70S AND 80S ACROSS THE MTS/VALLEYS...RHS ALL AREAS DROP TO BETWEEN 5 AND 15 PERCENT. FUELS ARE STILL TOO MOIST OR HAVE GREENED UP ACROSS THE SOUTHEAST PLAINS EAST OF THE I-25 CORRIDOR WITH RECENT RAINFALL SO NO HIGHLIGHTS ANTICIPATED FOR THEM AT THIS TIME. A SIMILAR SCENARIO IS EXPECTED FOR SATURDAY THOUGH SOUTHERLY WINDS ADVECT HIGHER DEW POINTS INTO THE SOUTHEAST CORNER OF THE STATE. ISOLATED THUNDERSTORMS WILL BE POSSIBLE NEAR THE CO/KS BORDER ALONG THIS DRY LINE. ELSEWHERE...LOOKS LIKE ANOTHER POTENTIAL RED FLAG DAY. DRY AND WINDY CONDITIONS CONTINUE FOR SUNDAY AND MONDAY WITH CRITICAL FIRE WEATHER CONDITIONS LIKELY TO CONTINUE FOR THE I-25 CORRIDOR AND POINTS WESTWARD THROUGH THE PERIOD. IF FUELS DRY OUT SUFFICIENTLY...ITS POSSIBLE MORE OF THE SOUTHEAST PLAINS MAY NEED TO BE INCLUDED. CHANCES FOR PRECIPITATION LOOK VERY LOW...THOUGH ECMWF HAS THE DRY LINE FLIRTING WITH THE EASTERN BORDER. UPPER RIDGE BUILDS OVER THE AREA FOR TUESDAY AND WEDNESDAY. ALTHOUGH IT WILL REMAIN HOT AND DRY...THIS DOES HELP TO TAPER BACK WINDS WHICH WILL ALLEVIATE THE CRITICAL FIRE WEATHER CONDITIONS SOME. -KT && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 311 PM MDT WED JUN 19 2013 VFR CONDITIONS ARE EXPECTED AT KALS...KCOS...AND KPUB THROUGH THURSDAY AFTERNOON. THE WINDS AT ALL THREE SITES WILL BEGIN TO WEAKEN AFTER SUNSET TONIGHT AND INCREASE AGAIN AT OR AROUND 17Z THURSDAY MORNING. -PJC && .FIRE WEATHER... ISSUED AT 311 PM MDT WED JUN 19 2013 CRITICAL CONDITIONS FOR FIRE WEATHER WILL CONTINUE FOR THURSDAY THROUGH MONDAY AS A PROLONGED HOT DRY AND WINDY PATTERN SETS UP OVER THE DISTRICT. CONDITIONS WILL BE MOST VOLATILE ACROSS THE MOUNTAIN AREAS...PARTICULARLY ACROSS THE SOUTHWEST AND CENTRAL MOUNTAINS AND SAN LUIS VALLEY. CRITICAL FIRE WEATHER CONDITIONS MAY BE A BIT MARGINAL FOR THE PIKES PEAK REGION ON FRIDAY...HOWEVER WINDS APPEAR TO STRENGTHEN ACROSS ALL OF THE AREA FOR SATURDAY THROUGH MONDAY. HUMIDITIES WILL DROP TO BETWEEN 5 AND 15 PERCENT EACH AFTERNOON AND WITH HAINES VALUES RUNNING AROUND 6...WHICH WILL LEAD TO CONDITIONS FAVORABLE FOR PLUME DOMINATED FIRES THROUGH THE PERIOD. ALTHOUGH FUELS ARE NOT CONSIDERED CRITICAL EAST OF THE I-25 CORRIDOR...HOT DRY CONDITIONS MAY CURE FUELS AND MAKE THEM RECEPTIVE AGAIN OVER THE WEEKEND...THUS EXTREME CARE SHOULD BE TAKEN TO AVOID WILDFIRE STARTS THROUGH THIS HOT DRY PERIOD ACROSS ALL OF SOUTH CENTRAL AND SOUTHEAST COLORADO. WINDS ARE EXPECTED TO WEAKEN SOME FOR TUESDAY AS HIGH PRESSURE BUILDS OVER THE REGION...HOWEVER IT IS LIKELY TO REMAIN HOT AND DRY NONE-THE-LESS. -KT/PJC && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ220>230. RED FLAG WARNING FROM 11 AM TO 8 PM MDT THURSDAY FOR COZ220>230. FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING FOR COZ220>230. && $$ SHORT TERM...PJC LONG TERM...KT AVIATION...PJC FIRE WEATHER...PJC/KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1116 AM MDT WED JUN 19 2013 .UPDATE... ISSUED AT 857 AM MDT WED JUN 19 2013 UPDATED GRIDS FOR CURRENT TEMPERATURE TRENDS AND SKY CONDITIONS. ALSO REFRESHED ALL FIRE WEATHER GRIDS WITH 12Z NAM12 DATA. -PJC && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM MDT WED JUN 19 2013 ...ISOLATED SEVERE THREAT FAR EASTERN PLAINS...FIRE WEATHER OVER MTNS/VALLEYS... CURRENTLY... AN ISOLATED STRONG TO SEVERE STORM HAS BEEN TRACKING OVER THE FAR SOUTHEAST PLAINS EARLY THIS MORNING. STORM HAS TRACKED IN REMOTE AREAS SO NO REPORTS...BUT ALGORITHMS HAVE BEEN INDICATING 2" HAIL WITH IT AT TIMES...AND MODEST ROTATION HAS BEEN OCCURRING ON AND OFF WITH THE CELL. OVER THE REST OF THE PLAINS...LLVL MSTR HAS REMAINED IN PLACE WITH SFC SE WINDS OVER THE REGION. SKIES HAVE CLOUDED UP OVER A GOOD PART OF THE PLAINS WITH CIGS IN THE MVFR/IFR CATEGORY. OVER THE INTERIOR MTNS...THE DRY AIR IS NOTED AS DWPTS ARE IN THE SINGLE DIGITS ACROSS THE SAN JUANS. TODAY... SIMULATIONS SHOW THE DRYLINE WILL REMAIN ON THE COLORADO SIDE OF THE CO/KS BORDER THIS AFTERNOON. ALTHOUGH TEMPS WILL BE WARMING ALOFT...CONVG ALONG THE BOUNDARY MAY ALLOW FOR ONE OR TWO STORMS TO FORM. LATEST HRRR WAS HINTING AT THIS. SPC ALSO HAS FAR E PLAINS IN SLIGHT RISK. CAPE IS FCST TO BE SIGNIFICANT...3000 J/KG...AND SHEAR WILL BE IN THE 35-45 KT RANGE...SO IF ANY STORM GOES UP IT WILL ROTATE AND IT WILL HAVE THE POTENTIAL TO PRODUCE SOME BIG HAIL. LCLS WILL BE HIGH SO TORNADO THREAT IS VERY LOW. OVER THE REST OF THE REGION...METEOROLOGICAL CONDITIONS WILL BE FAVORABLE FOR EXTREME FIRE BEHAVIOR GIVEN THE LOW DWPTS AND GUSTY SW WINDS. QUITE A FEW AREAS ON THE PLAINS HAVE RECEIVED SOME BENEFICIAL RAIN SO THE THREAT IS LESS ALONG THE I-25 CORRIDOR...HOWEVER IT WILL DRY OUT QUICKLY TODAY AND ANY AREAS WHICH HAVE NOT RECEIVED ANY SIGNIF RAIN WILL HAVE THE POTENTIAL FOR EXTREME FIRE BEHAVIOR. IT WILL BE MUCH WARMER TODAY THAN THE YESTERDAY...WITH HIGHS APPROACHING 100 OVER THE LOWER ARK RVR VALLEY. EXPECT 70S MTNS WITH 80S IN THE VALLEYS. TEMPS AROUND 90F WILL OCCUR IN MOST OF EL PASO COUNTY. TONIGHT... EXCEPT FOR THE SLIGHT CHANCE OF A SUPERCELL OVER THE FAR E PLAINS EARLY THIS EVENING...IT WILL BE DRY. RH RECOVERY WILL BE VERY POOR OVER THE MTNS...VALLEYS AND I-25 CORRIDOR REGION. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 323 AM MDT WED JUN 19 2013 ...HIGH FIRE DANGER... MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED WITH A SLOW MOVING SYSTEM OUT OF THE PACIFIC NORTHWEST INTO THE NORTHERN PLAINS AND PERSISTENT SOUTHWESTERLY FLOW ACROSS THE ROCKIES. THIS WILL PUT THE REGION UNDER FAVORABLE CONDITIONS FOR HIGH FIRE DANGER. THURSDAY THROUGH SATURDAY...STRONG DRY PERSISTENT SOUTHWESTERLY FLOW WILL ENCOMPASS SOUTHERN COLORADO THROUGH THIS PERIOD. THIS WILL SET THE STAGE FOR EXTREME FIRE DANGER FOR MUCH OF SOUTHERN COLORADO...ESPECIALLY WEST OF I-25. ALREADY HAVE A FIRE WEATHER WATCH OUT FOR THURSDAY AFTERNOON...AND WILL LIKELY NEED TO RAISE ONE FOR FRIDAY AFTERNOON AS WELL IN THE NEAR FUTURE. WIDESPREAD WINDS OF 20 TO 30 MPH ARE EXPECTED EACH AFTERNOON THROUGH SATURDAY WHILE HUMIDITY VALUES WILL DROP WELL BELOW 10 PERCENT. IN ADDITION THE AFTERNOON MIXING WILL ALLOW TEMPERATURES TO CLIMB INTO THE UPPER 90S TO LOWER 100S ACROSS THE PLAINS. THERE ARE SOME FIRE WEATHER CONCERNS EAST OF I-25 AS WELL...CONDITIONS WILL BE FAVORABLE HOWEVER FUEL STATUS AND RECENT HEAVY RAINS PRECLUDE ANY FIRE WEATHER HIGHLIGHTS AT THIS TIME. FINE FUELS WILL NEED TO BE WATCHED AND MAY CURE QUICKLY WITH PERSISTENT DRY AND WINDY CONDITIONS LEADING TO ENHANCED FIRE DANGER. THE ONLY AREA THAT MAY SEE ANY PRECIPITATION DURING THE EXTENDED PERIOD WILL BE THE FAR SOUTHEAST PLAINS ON FRIDAY AFTERNOON AND EVENING WHERE AN ISOLATED THUNDERSTORM WILL BE POSSIBLE...BUT CONFIDENCE IS LOW IN OCCURRENCE AT THIS TIME. SUNDAY THROUGH TUESDAY...THE UPPER PATTERN BEGINS TO SHIFT ON SUNDAY WITH THE UPPER SYSTEM OVER THE NORTHERN PLAINS EJECTING INTO THE GREAT LAKES AND HIGH PRESSURE BUILDING NORTHWARD OUT OF THE DESERT SOUTHWEST. TEMPERATURES MAY BE SLIGHTLY COOLER ON SUNDAY BEHIND A WEAK COLD FRONT...BUT WE SHOULD STILL MANAGE MID TO UPPER 90S ACROSS THE PLAINS BEFORE WARMING BACK UP FOR MONDAY AND TUESDAY. HUMIDITY VALUES WILL REMAIN LOW THROUGH THIS PERIOD...BUT WITH HIGH PRESSURE BUILDING OVERHEAD...WINDS SHOULD WEAKEN AND HELP REDUCE THE HIGH FIRE DANGER. THE EXCEPTION MAY BE THE CONTINENTAL DIVIDE AREA SUNDAY AND MONDAY WHERE SOUTHWESTERLY FLOW WILL REMAIN A BIT STRONGER BEFORE WEAKENING ON TUESDAY. THIS WILL NEED TO BE MONITORED. CURRENT MODEL PROJECTIONS INDICATING THAT WE WILL REMAIN DRY WITH NO CHANCES FOR PRECIPITATION EARLY TO MIDDLE NEXT WEEK. MOZLEY && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1108 AM MDT WED JUN 19 2013 VFR CONDITIONS ARE EXPECTED AT KALS...KCOS...AND KPUB THROUGH 18Z THURSDAY. THE MAIN CONCERN AT THESE SITES WILL BE GUSTY SOUTHWEST WINDS LATE THIS MORNING THROUGH THIS EVENING. -PJC && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ220>230. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR COZ220>230. && $$ UPDATE...PJC SHORT TERM...HODANISH LONG TERM...MOZLEY AVIATION...PJC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
157 PM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TODAY AND REMAINS IN CONTROL THROUGH THE END OF THE WEEK. A WEAK COLD FRONT WILL PASS THROUGH THE AREA SUNDAY NIGHT INTO MONDAY WITH HIGH PRESSURE RETURNING IN ITS WAKE. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 16Z SURFACE ANALYSIS SHOWS HIGH PRESSURE BUILDING INTO THE TRI- STATE AREA. LAST SEVERAL HOURS OF RAP ANALYSIS AT H500 INDICATE A SHORTWAVE TROUGH AND WEAK VORT MAX MOVING THROUGH...THERE WILL BE LITTLE CONSEQUENCE FROM THIS FEATURE. LIGHT NORTH TO NORTHEASTERLY FLOW WILL CONTINUE INTO THE AFTERNOON WITH JUST A FEW FAIR WEATHER CLOUDS. LATE AFTERNOON SEA BREEZES ARE EXPECTED AT THE COAST. OTHERWISE...MOSTLY SUNNY WITH A DRY AIRMASS AS SURFACE DEWPOINTS DROP INTO THE 40S. MIXING PROFILES SUPPORT HIGHS OF MOSTLY 75-80. THERE IS A MODERATE RISK OF RIP CURRENTS AT ATLANTIC OCEAN BEACHES TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... LIGHT TO CALM WINDS AND A MOSTLY CLEAR SKY TONIGHT WILL ALLOW FOR DECENT RADIATIONAL COOLING OUTSIDE OF THE CITY...WITH LOWS 5-10 DEGREES BELOW NORMAL IN MOST OF THE SUBURBS. HIGH PRESSURE CENTER SHIFTS OFFSHORE ON THURSDAY WITH A RETURN SW-S FLOW SETTING UP. SEA BREEZES ARE LIKELY AS WINDS REMAIN LIGHT THROUGH THE FIRST FEW THOUSAND FEET IN ELEVATION. SURFACE DEW POINTS SHOULD REMAIN AT COMFORTABLE LEVELS IN SPITE OF THIS AS DRIER AIR FROM ALOFT MIXES DOWN. MIXING WON/T BE AS DEEP AS TODAY DUE TO SUBSIDENCE...HOWEVER TEMPERATURES AT THE TOP OF THE MIXED LAYER SHOULD ALLOW FOR HIGHS OF GENERALLY 75-80 ONCE AGAIN. DRY WEATHER CONTINUES INTO THURSDAY NIGHT WITH LOWS STILL BELOW NORMAL...BUT NOT AS COOL AS TONIGHT. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... GLOBAL MODELS IN GOOD AGREEMENT WITH THE OVERALL PATTERN IN THE LONG TERM TIME FRAME. ALOFT...A MEAN TROUGH WILL GIVE WAY TO SLIGHTLY RISING HEIGHTS BY SATURDAY AND CONTINUING TO BUILD THROUGH THE WEEK. GFS IS SLIGHTLY MORE AGGRESSIVE WITH THE STRONG RIDGE MOVING IN WHILE THE ECMWF TRACKS A SHORTWAVE THROUGH MONDAY AND THEN QUICKLY RISES THE HEIGHTS. AT THE SURFACE... HIGH PRESSURE REMAINS IN CONTROL THROUGH THE LONG TERM WITH A GENERAL SOUTH-SOUTHWEST FLOW. USED A MAV/MET BLEND FOR TEMPS ON FRIDAY WITH A GOOD GENERAL AGREEMENT FOR NEAR NORMAL VALUES. TEMPS WILL CONTINUE TO MODERATE THROUGH THE WEEK AND USED WPC GUIDANCE AS IT SEEMED REASONABLE WITH NO MAJOR TEMPERATURE FLUXES. NEAR TO JUST ABOVE NORMAL TEMPS ARE EXPECTED. MODELS TRYING TO HINT AT A FEW SHOWERS ON FRIDAY BUT HAVE CONTINUED THE DRY FORECAST WITH LITTLE INSTABILITY OR LIFT. ON SATURDAY...A COLD FRONT WILL WEAKEN AND DISSIPATE BY THE TIME IT REACHES THE WESTERN CWA BOUNDARY. WITH SOME INSTABILITY IN PLACE WITH AFTERNOON HEATING...THIS BOUNDARY COULD CREATE A FEW SHOWERS...MOSTLY IN FAR NORTH AND WEST ZONES. HAVE LEFT CHANCE POPS FOR THAT AREA. HIGHEST CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE SUNDAY NIGHT INTO MONDAY AS A COLD FRONT APPROACHES AND POSSIBLY REMAINING STATIONARY THROUGH MONDAY. ECMWF ALSO TRYING TO HINT AT A POTENTIAL DECAYING MCS TRACKING SE ALONG THE FRONT...ALONG THE SOUTHERN SIDE OF AN UPPER JET. WILL GENERALLY KEEP CHANCE POPS IN THE AREAS NORTH AND WEST OF NYC AND SLIGHT CHANCE ELSEWHERE. THE NORTHERN AREAS WILL HAVE THE HIGHEST INSTABILITY DURING THE DAY AND THEREFORE THE GREATEST PRECIP CHANCES. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... HIPRES BUILDS OVER THE REGION TNGT AND OFFSHORE ON THU. VFR THROUGH THE TAF PERIOD. N WINDS INTO THIS EVE EXCEPT WHERE SEA BREEZE FLOW DEVELOPS. GUST POTENTIAL WILL DECREASE THRU THE DAY AS WINDS ALOFT LIGHTEN. NEARLY CALM OVERNIGHT WITH SLY FLOW DEVELOPING AFT 12Z THU. ENHANCED FLOW ALONG THE S COASTS AFT 17-19Z THU...WITH SUSTAINED WINDS LIKELY TO BE AOA 15KT AT KJFK. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: VARIABILITY IN PREVAILING WIND DIRECTION POSSIBLE THRU 21Z AS GUST FREQUENCY DECREASES. SEA BREEZE EXPECTED TO DEVELOP DURING TAF TEMPO PERIOD. KLGA FCSTER COMMENTS: VARIABILITY IN PREVAILING WIND DIRECTION POSSIBLE THRU 23Z AS GUST FREQUENCY DECREASES. SEA BREEZE EXPECTED TO DEVELOP DURING TAF TEMPO PERIOD. KEWR FCSTER COMMENTS: VARIABILITY IN PREVAILING WIND DIRECTION POSSIBLE THRU 00Z AS GUST FREQUENCY DECREASES. SEA BREEZE EXPECTED TO DEVELOP DURING TAF TEMPO PERIOD. KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. KISP FCSTER COMMENTS: VARIABILITY IN PREVAILING WIND DIRECTION POSSIBLE THRU 22Z AS GUST FREQUENCY DECREASES. SEA BREEZE EXPECTED TO DEVELOP DURING TAF TEMPO PERIOD. .OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY... .THU-FRI...VFR. PREVAILING SW WINDS. .SAT-MON...MAINLY VFR. AREAS OF MVFR OR LWR IN THE MRNG. ISOLD-SCT AFTN/EVE TSTMS POSSIBLE...ESPECIALLY N AND W OF THE CITY. SW WINDS. && .MARINE... HIGH PRESSURE BUILDS IN OVER THE WATERS THROUGH THE DAY TODAY. A NORTHERLY FLOW AT AROUND 15 KT WEAKENS THIS AFTERNOON WITH LOCAL SEA BREEZE DIRECTIONS DEVELOPING NEARSHORE LATE IN THE DAY. A LIGHT RETURN S TO SW FLOW DEVELOPS FOR THURSDAY AS THE CENTER OF HIGH PRESSURE SHIFTS OFFSHORE. TRANQUIL CONDITIONS THEREFORE PREVAIL. WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA THROUGH EARLY NEXT WEEK AS HIGH PRESSURE REMAINS OVER THE AREA. && .HYDROLOGY... DRY WEATHER IS EXPECTED THROUGH AT LEAST SUNDAY MORNING. SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH AFTERNOON SUN-TUE BUT NO WIDESPREAD SIGNIFICANT PRECIPITATION IS EXPECTED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...JC/LN NEAR TERM...DS SHORT TERM...JC LONG TERM...LN AVIATION...JMC MARINE...JC/LN HYDROLOGY...JC/LN
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1236 PM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TODAY AND REMAINS IN CONTROL THROUGH THE END OF THE WEEK. A WEAK COLD FRONT WILL PASS THROUGH THE AREA SUNDAY NIGHT INTO MONDAY WITH HIGH PRESSURE RETURNING IN ITS WAKE. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 16Z SURFACE ANALYSIS SHOWS HIGH PRESSURE BUILDING INTO THE TRI- STATE AREA. LAST SEVERAL HUORS OF RAP ANALYSIS AT H500 INDICATE A SHORTWAVE TROUGH AND WEAK VORT MAX MOVING THROUGH...THERE WILL BE LITTLE CONSEQUENCE FROM THIS FEATURE. LIGHT NORTH TO NORTHEASTERLY FLOW WILL CONTINUE INTO THE AFTERNOON WITH JUST A FEW FAIR WEATHER CLOUDS. LATE AFTERNOON SEA BREEZES ARE EXPECTED AT THE COAST. OTHERWISE...MOSTLY SUNNY WITH A DRY AIRMASS AS SURFACE DEWPOINTS DROP INTO THE 40S. MIXING PROFILES SUPPORT HIGHS OF MOSTLY 75-80. THERE IS A MODERATE RISK OF RIP CURRENTS AT ATLANTIC OCEAN BEACHES TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... LIGHT TO CALM WINDS AND A MOSTLY CLEAR SKY TONIGHT WILL ALLOW FOR DECENT RADIATIONAL COOLING OUTSIDE OF THE CITY...WITH LOWS 5-10 DEGREES BELOW NORMAL IN MOST OF THE SUBURBS. HIGH PRESSURE CENTER SHIFTS OFFSHORE ON THURSDAY WITH A RETURN SW-S FLOW SETTING UP. SEA BREEZES ARE LIKELY AS WINDS REMAIN LIGHT THROUGH THE FIRST FEW THOUSAND FEET IN ELEVATION. SURFACE DEW POINTS SHOULD REMAIN AT COMFORTABLE LEVELS IN SPITE OF THIS AS DRIER AIR FROM ALOFT MIXES DOWN. MIXING WON/T BE AS DEEP AS TODAY DUE TO SUBSIDENCE...HOWEVER TEMPERATURES AT THE TOP OF THE MIXED LAYER SHOULD ALLOW FOR HIGHS OF GENERALLY 75-80 ONCE AGAIN. DRY WEATHER CONTINUES INTO THURSDAY NIGHT WITH LOWS STILL BELOW NORMAL...BUT NOT AS COOL AS TONIGHT. && .LONG TERM /FRIDAY THROUGH TUESDAY/... GLOBAL MODELS IN GOOD AGREEMENT WITH THE OVERALL PATTERN IN THE LONG TERM TIME FRAME. ALOFT...A MEAN TROUGH WILL GIVE WAY TO SLIGHTLY RISING HEIGHTS BY SATURDAY AND CONTINUING TO BUILD THROUGH THE WEEK. GFS IS SLIGHTLY MORE AGGRESSIVE WITH THE STRONG RIDGE MOVING IN WHILE THE ECMWF TRACKS A SHORTWAVE THROUGH MONDAY AND THEN QUICKLY RISES THE HEIGHTS. AT THE SURFACE... HIGH PRESSURE REMAINS IN CONTROL THROUGH THE LONG TERM WITH A GENERAL SOUTH-SOUTHWEST FLOW. USED A MAV/MET BLEND FOR TEMPS ON FRIDAY WITH A GOOD GENERAL AGREEMENT FOR NEAR NORMAL VALUES. TEMPS WILL CONTINUE TO MODERATE THROUGH THE WEEK AND USED WPC GUIDANCE AS IT SEEMED REASONABLE WITH NO MAJOR TEMPERATURE FLUXES. NEAR TO JUST ABOVE NORMAL TEMPS ARE EXPECTED. MODELS TRYING TO HINT AT A FEW SHOWERS ON FRIDAY BUT HAVE CONTINUED THE DRY FORECAST WITH LITTLE INSTABILITY OR LIFT. ON SATURDAY...A COLD FRONT WILL WEAKEN AND DISSIPATE BY THE TIME IT REACHES THE WESTERN CWA BOUNDARY. WITH SOME INSTABILITY IN PLACE WITH AFTERNOON HEATING...THIS BOUNDARY COULD CREATE A FEW SHOWERS...MOSTLY IN FAR NORTH AND WEST ZONES. HAVE LEFT CHANCE POPS FOR THAT AREA. HIGHEST CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE SUNDAY NIGHT INTO MONDAY AS A COLD FRONT APPROACHES AND POSSIBLY REMAINING STATIONARY THROUGH MONDAY. ECMWF ALSO TRYING TO HINT AT A POTENTIAL DECAYING MCS TRACKING SE ALONG THE FRONT...ALONG THE SOUTHERN SIDE OF AN UPPER JET. WILL GENERALLY KEEP CHANCE POPS IN THE AREAS NORTH AND WEST OF NYC AND SLIGHT CHANCE ELSEWHERE. THE NORTHERN AREAS WILL HAVE THE HIGHEST INSTABILITY DURING THE DAY AND THEREFORE THE GREATEST PRECIP CHANCES. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES THROUGH TONIGHT. VFR THROUGH THE TAF PERIOD. MID AND HIGH CLOUDS GRADUALLY CONTINUE TO DISSIPATE THROUGH THE DAY...THEN SKC TONIGHT. N-NNE AROUND 10 KT THROUGH AT LEAST EARLY AFTERNOON WITH ISOLATED GUSTS 15-20 KT...EXCEPT AT KEWR WHICH LIKELY WILL HAVE MORE FREQUENT GUSTS FROM MIDDAY INTO EARLY AFTERNOON. SEA BREEZE LIKELY MID-LATE AFTERNOON/EARLY EVENING KBDR/KGON/KJFK/KISP/KLGA/KEWR. WINDS BECOME LIGHT AND VARIABLE AT ALL TERMINALS THIS EVENING. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: MODERATE-HIGH CONFIDENCE IN SEABREEZE - LOW CONFIDENCE IN EXACT TIMING. COULD BE OFF +/- 2 HOURS. ISOLATED GUSTS TO 15-20 KT POSSIBLE THROUGH EARLY AFTERNOON. HIGH CONFIDENCE IN WINDS TO THE RIGHT OF 300 TRUE THROUGH EARLY AFTERNOON. KLGA FCSTER COMMENTS: MODERATE CONFIDENCE IN SEABREEZE - LOW CONFIDENCE IN EXACT TIMING. COULD BE OFF +/- 2-3 HOURS. ISOLATED GUSTS TO 15-20 KT POSSIBLE THROUGH EARLY AFTERNOON. HIGH CONFIDENCE IN WINDS TO THE RIGHT OF 300 TRUE THROUGH EARLY AFTERNOON. KEWR FCSTER COMMENTS: MODERATE CONFIDENCE IN SEABREEZE - LOW CONFIDENCE IN EXACT TIMING. COULD BE OFF +/- 2-3 HOURS. ISOLATED GUSTS TO 15-20 KT POSSIBLE THROUGH MIDDAY...THEN MODERATE CONFIDENCE IN MORE FREQUENT GUSTS AROUND 16-20Z. HIGH CONFIDENCE IN WINDS TO THE RIGHT OF 300 TRUE THROUGH EARLY AFTERNOON. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: LOW-MODERATE CONFIDENCE IN SEABREEZE - LOW CONFIDENCE IN EXACT TIMING. COULD BE OFF +/- 2-3 HOURS. ISOLATED GUSTS TO 15-20 KT POSSIBLE THROUGH EARLY AFTERNOON. KHPN FCSTER COMMENTS: VERY LOW CHANCE OF SEABREEZE LATE THIS AFTERNOON/EARLY THIS EVENING. ISOLATED GUSTS TO 15-20 KT POSSIBLE THROUGH EARLY AFTERNOON. KISP FCSTER COMMENTS: MODERATE-HIGH CONFIDENCE IN SEABREEZE - LOW CONFIDENCE IN EXACT TIMING. COULD BE OFF +/- 2 HOURS. ISOLATED GUSTS TO 15-20 KT POSSIBLE THROUGH EARLY AFTERNOON. .OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY... .THURSDAY-SATURDAY MORNING...VFR. .SATURDAY AFTERNOON/NIGHT. MAINLY VFR...EXCEPT MVFR OR LOWER POSSIBLE IN ISOLD-SCT SHRA/TSRA MAINLY TO THE N/W OF CITY TERMINALS IN THE AFTERNOON/EVENING. .SUNDAY...MVFR OR LOWER POSSIBLE. && .MARINE... HIGH PRESSURE BUILDS IN OVER THE WATERS THROUGH THE DAY TODAY. A NORTHERLY FLOW AT AROUND 15 KT WEAKENS THIS AFTERNOON WITH LOCAL SEA BREEZE DIRECTIONS DEVELOPING NEARSHORE LATE IN THE DAY. A LIGHT RETURN S TO SW FLOW DEVELOPS FOR THURSDAY AS THE CENTER OF HIGH PRESSURE SHIFTS OFFSHORE. TRANQUIL CONDITIONS THEREFORE PREVAIL. WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CRITERIA THROUGH EARLY NEXT WEEK AS HIGH PRESSURE REMAINS OVER THE AREA. && .HYDROLOGY... DRY WEATHER IS EXPECTED THROUGH AT LEAST SUNDAY MORNING. SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH AFTERNOON SUN-TUE BUT NO WIDESPREAD SIGNIFICANT PRECIPITATION IS EXPECTED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...JC/LN NEAR TERM...DS SHORT TERM...JC LONG TERM...LN AVIATION...JMC/MALOIT MARINE...JC/LN/DS HYDROLOGY...JC/LN
AREA FORECAST DISCUSSION
NWS MIAMI FL
231 PM EDT WED JUN 19 2013 .SHORT TERM (TONIGHT-FRIDAY NIGHT)... EARLY AFTERNOON SHOWERS AND THUNDERSTORMS HAVE ALREADY BEGUN TO INITIATE ACROSS PORTIONS OF THE LOCAL AREA AS THE EAST AND WEST COAST SEA BREEZES BEGIN TO PENETRATE INLAND. SOME OF THIS ACTIVITY APPEARS TO HAVE BEEN ENHANCED BY A MID-LEVEL VORT PROGRESSING EASTWARD FROM LAKE OKEECHOBEE EARLIER...WHICH SHOWED UP WELL ON THE VISIBLE SATELLITE LOOP. THE LATEST HRRR AND WRF MODEL REFLECTIVITIES APPEAR TO BE INITIALIZING WELL WITH THE LATEST RADAR TRENDS AND GENERALLY INDICATE THIS EARLY AFTERNOON ACTIVITY CONTINUING TO DEVELOP AND BECOMING CONCENTRATED ACROSS THE INTERIOR AND WRN LOCATIONS THROUGH THE LATE AFTERNOON AND EARLY EVENING PERIODS AS THE SEA BREEZES BOUNDARIES PENETRATE FARTHER INLAND AND MERGE. ALTHOUGH MID-LEVEL LAPSE RATES AND H5 TEMPERATURES ARE NOT VERY IMPRESSIVE TODAY...A FEW STORMS MAY BECOME STRONG WITH THE MAIN THREAT BEING GUSTY WINDS UP TO 45 MPH. TONIGHT THROUGH FRIDAY NIGHT...THE GENERAL TREND WITH ABOVE AVERAGE TEMPERATURES WILL PERSIST...ESPECIALLY THROUGH THE OVERNIGHT HOURS WHEN TEMPERATURES ARE FORECAST TO REMAIN SEVERAL DEGREES ABOVE AVERAGE. AS A RESULT...WARMER MINIMUM TEMPERATURE RECORDS COULD BE BROKEN EACH NIGHT. MODEL PRECIPITABLE WATER VALUES INDICATE A SLIGHT DRYING TREND THURSDAY THROUGH FRIDAY AHEAD OF AN APPROACHING TROPICAL WAVE WITH VALUES TRENDING DOWN TO AROUND 1.5". HOWEVER...DAYTIME HEATING COMBINED WITH SE LOW-LEVEL FLOW UP TO H7 AROUND THE SUBTROPICAL RIDGE AXIS WILL BE ENOUGH TO SUPPORT ANOTHER ROUND OF ISLTD/SCT AFTERNOON SHOWERS/TSTMS...ESPECIALLY ACROSS THE INTERIOR LOCATIONS THROUGH THE LATE AFTERNOON AND EARLY EVENING PERIODS. HAZY CONDITIONS DUE TO HIGHER CONCENTRATIONS OF DUST SPREADING INTO THE AREA FROM THE SE WILL REMAIN POSSIBLE EACH DAY. .LONG TERM (SATURDAY-TUESDAY)... MODELS REMAIN PERSISTENT FROM RUN TO RUN AND CONTINUE TO INDICATE A TROPICAL WAVE APPROACHING AND MOVING THROUGH THE AREA OVER THE WEEKEND. MODEL PWS ASSOCIATED WITH THIS WAVE ARE FORECAST TO NEAR THE 2" MARK BY SUNDAY...WHICH SHOULD TRANSLATE TO HIGHER RAIN CHANCES. CONDITIONS SHOULD TREND BACK TO NORMAL THROUGH THE EARLY HALF OF THE UPCOMING WEEK AS THE WAVE TRACKS WEST AND AWAY FROM THE LOCAL AREA. && .AVIATION... VFR CONDITIONS WILL PREVAIL THROUGHOUT THE FORECAST PERIOD. WINDS WILL REMAIN OUT OF THE EAST SOUTHEAST BETWEEN 10 TO 15 KNOTS THIS AFTERNOON AND THIS EVENING ACROSS THE EAST COAST TERMINALS. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS AFTERNOON MAINLY WEST OF THE EAST COAST TERMINALS. AT KAPF, A WEST COAST SEA BREEZE WILL DEVELOP LATER THIS AFTERNOON. WINDS WILL DIMINISH ACROSS ALL TERMINALS THIS EVENING AND THEN THEY WILL INCREASE AGAIN BY THE MIDDLE OF THURSDAY MORNING. && .MARINE... LIGHT TO MODERATE SOUTHEAST WINDS ASSOCIATED WITH HIGH PRESSURE WILL PERSIST THROUGH THE WEEK. THE BEST CHANCE FOR ISOLATED SHOWERS AND STORMS WILL BE THROUGH THE OVERNIGHT AND EARLY MORNING HOURS EACH DAY. A WEAK TROPICAL WAVE WILL APPROACH AND MOVE THROUGH THE MARINE AREA OVER THE WEEKEND AND MAY TRANSLATE TO BETTER SHOWER/TSTM COVERAGE. && .FIRE WEATHER... RELATIVE HUMIDITIES ARE FORECAST TO REMAIN ABOVE CRITICAL LEVELS EACH DAY. LIGHT SOUTHEAST WINDS ARE EXPECTED TO PERSIST THROUGH MUCH OF THE WEEK...EXCEPT THROUGH THE AFTERNOON PERIODS AS THE GULF COAST SEA BREEZES PENETRATES INLAND ACROSS PORTIONS OF COLLIER COUNTY. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 77 87 78 88 / 20 20 20 20 FORT LAUDERDALE 80 89 81 89 / 20 20 20 20 MIAMI 78 89 80 89 / 20 20 20 20 NAPLES 75 92 74 93 / 20 30 20 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...85/AG AVIATION/RADAR...55/CWC
AREA FORECAST DISCUSSION
NWS DES MOINES IA
414 PM CDT WED JUN 19 2013 .SHORT TERM.../TONIGHT /... ISSUED AT 413 PM CDT WED JUN 19 2013 MAIN FORECAST CONCERN IS WITH SMALL CHANCES OF ISOLATED STORMS ACROSS THE WEST AND NORTH THIS AFTERNOON THROUGH THURSDAY MORNING. LEANED TOWARD A BLEND OF THE HI-RES MODELS FOR TRENDS TONIGHT INTO THURSDAY MORNING. THE ARW-WEST AND LATEST HRRR HAVE SOME ISOLATED THUNDERSTORMS DEVELOPING THIS AFTERNOON INTO THE EARLY EVENING ACROSS WESTERN TO NORTHERN PORTIONS OF THE FORECAST AREA. CAP SEEMS TO BE WINNING ATTM AND CUT BACK ON POPS TO MAINLY THE FAR WEST EVEN THOUGH SURFACE BASED CAPE AROUND 1000-1500 J/KG WITH MUCAPE SLIGHTLY HIGHER. THERE IS VERY LITTLE...IF ANY SHEAR PRESENT THROUGH THE EVENING HOURS..SO NOT ANTICIPATING ANYTHING LONG-LIVED. WEAK THETA-E ADVECTION MOVES INTO WESTERN IOWA PAST 06Z AS A BROAD AREA OF VORTICITY CUTS THROUGH THE REGION TONIGHT. TRANSITIONED CHANCE POPS FURTHER EAST OVERNIGHT AND MAINLY KEPT HIGHEST POPS ACROSS NORTHERN IOWA PAST 06Z THURSDAY WHERE BEST FORCING IS PRESENT. .LONG TERM.../THURSDAY THROUGH WEDNESDAY/... ISSUED AT 413 PM CDT WED JUN 19 2013 UPPER LEVEL LOW CONTINUES SLOWLY MOVE OVER THE PACIFIC NORTHWEST TODAY AND WILL MOVE LITTLE THROUGH SATURDAY BEFORE BEGINNING TO LIFT NORTHEAST INTO CANADA ON SUNDAY. WEAK RIDGING OVER IOWA WILL SLOWLY SHIFT EAST DURING THIS TIME AS WELL AND WILL FOCUS SOUTHWEST FLOW INTO THE UPPER MIDWEST. NUMEROUS SHORT WAVES ARE STILL EXPECTED TO RIPPLE THROUGH THIS FLOW AND IMPACT MAINLY NORTHERN IOWA AND AREAS TO THE NORTH DURING THE PERIOD WHILE WARM AIR ALOFT DRIVES A CAP INTO CENTRAL AND SOUTHERN IOWA FRIDAY INTO SATURDAY. SURFACE LOW PRESSURE WILL LIFT NORTH THROUGH KANSAS AND NEBRASKA THURSDAY AND THURSDAY NIGHT WITH A SECONDARY WARM FRONT MOVING NORTH THROUGH THE STATE. WHILE THE PRIMARY FRONTAL BOUNDARY WILL BE NORTH INTO MINNESOTA DURING THE AFTERNOON...THE POTENTIAL FOR THE SECONDARY BOUNDARY TO LIFT INTO WEST CENTRAL DURING THE AFTERNOON. SOME MIXED LAYER CIN WILL BE IN PLACE THROUGH A WEAK SHORT WAVE IS EXPECTED TO MOVE ACROSS THE AREA WITH MID LEVEL COOLING THAT MAY BE ENOUGH TO KICK OFF A FEW STORMS. IF STORMS FIRE...CERTAINLY A FEW SUPERCELLS WOULD BE POSSIBLE. STILL SOME HINTS THAT A DAKOTAS MCS COULD DROP INTO NORTHERN IOWA THURSDAY NIGHT AND COULD BRING AN ADDITIONAL CHANCE FOR SEVERE WEATHER. MUCH OF THE AREA OVER THE CENTRAL AND SOUTH BECOMES CAPPED FRIDAY INTO THE WEEKEND AND HAVE BEGUN TO DROP POPS ACROSS THESE AREAS WITH THE PRIMARY FOCUS BEING ACROSS THE NORTH. A VERY WARM AND HUMID AIR MASS WILL LIFT INTO THE AREA WITH HIGH TEMPERATURES IN HIGHS IN THE UPPER 80S TO MID 90S AND DEWPOINTS RISING INTO THE 70S. THE SUBTROPICAL HIGH CONTINUES TO EXERT ITSELF OVER THE SOUTHERN PLAINS INTO EARLY NEXT WEEK AND BUILDING NORTH. THE RING OF FIRE MAY CLIP INTO NORTHERN IOWA DURING END OF THE PERIOD BY THE PRIMARY FOCUS WILL BE TO THE NORTH WITH SUMMER IN PLACE OVER IOWA. && .AVIATION...19/18Z ISSUED AT 1239 PM CDT WED JUN 19 2013 VFR CONDITIONS LOOK TO PREVAIL THROUGHOUT THE FORECAST PERIOD. WEAK THETA-E ADVECTION DEVELOPS ACROSS WESTERN IOWA OVERNIGHT TONIGHT AND MAY SPAWN SOME ISOLATED CONVECTION. LEFT MENTION OF ANY THUNDER OUT OF THE TAFS ATTM AS LOW CONFIDENCE IN COVERAGE. OTHERWISE...WINDS WILL INCREASE LATE THURSDAY MORNING AND INTRODUCED GUSTS INTO THE 20-25 KNOT RANGE. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...PODRAZIK LONG TERM...DONAVON AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1244 PM CDT WED JUN 19 2013 ...UPDATED AVIATION DISCUSSION... .SHORT TERM.../TODAY/... ISSUED AT 339 AM CDT WED JUN 19 2013 HIGH PRESSURE RIDGE MOVING OFF TO THE EAST NOW WITH WAA BEGINNING TO MOVE INTO WRN IA. SAT PIX SHOW AN INCREASE IN CLODS FROM DECAYING BLOWOFF CLOUDS. DEEPER MOISTURE CONVERGENCE MOVING INTO SWRN IA WILL BRING AT LEAST ISOLATED TSRA THIS MORNING AS WAA ARC LIFTS NORTHEAST ACROSS THE CWA. KEPT THE PRECIP TO THE WEST HALF HOWEVER. COMBINATION OF NAMDNG5 AND HRRR GIVES A REASONABLE PRESENTATION OF EXPECTED OUTCOME. TEMPS TODAY VERY DEPENDENT ON CLOUD COVER. FEEL THERE WILL BE ENOUGH BREAKS TO GET HIGHS A LITTLE ABOVE MOS GUID AND WARMER THAN YESTERDAY IN MOST LOCATIONS. .LONG TERM.../TONIGHT THROUGH TUESDAY/... ISSUED AT 339 AM CDT WED JUN 19 2013 COMPLICATED FORECAST FOR EXTENDED...WITH MANY PERIODS OF POPS...AND SOMEWHAT LOW CONFIDENCE IN TIMING...WITH BREAKS IN PRECIP CHANCES FROM TIME TO TIME THROUGH THE REMAINDER OF THE WEEK. LARGE UPPER LEVEL LOW WILL BE DRIVER FOR PRECIPITATION CHANCES TROUGH MUCH OF THE PERIOD. LOW WILL REMAIN PRIMARILY OVER PAC NW...AND IS BEGINNING TO SLOWLY PUSH INLAND ATTM. MODELS HAVE SIGNIFICANT DISCREPANCIES OVER PLACEMENT OF LOW...BUT SHOULD COME INTO BETTER AGREEMENT AS LOW PUSHES INLAND. RIDGE REMAINS OVER IOWA THROUGH MUCH OF PERIOD...WITH SHORTWAVES PUSHING THROUGH SPARKING CONVECTION CHANCES. MODELS HAVE SIGNIFICANTLY SLOWED DOWN SHORT WAVES PROPAGATION EASTWARD...WITH FOCUS FOR DEVELOPMENT IN CENTRAL NE PUSHING INTO IOWA LATE OVERNIGHT. HAVE THEREFORE SLOWED POPS FOR OVERNIGHT...THOUGH COULD SEE SOME DEVELOPMENT AHEAD OF MAIN PRECIP BAND WITH THETA-E ADVECTION. SYSTEM IS SLOW MOVING...WITH PRECIP THROUGH THURSDAY. STRONG SHORTWAVE SET TO TRACK ACROSS NORTHERN PLAINS LATE THURSDAY. THIS WILL LIKELY BE THE FOCUS FOR SEVERE WEATHER ACROSS THE DAKOTAS...AND MAY FORM INTO MCS PUSHING ACROSS IOWA...WITH NORTHERN IOWA MOST LIKELY LOCATION OVERNIGHT THURSDAY. SEVERE WEATHER WILL BE POSSIBLE WITH THIS SYSTEM. SHORTWAVE EXPECTED TO TRACK ACROSS SOUTHERN SD/MN AND HEAVIEST PRECIP MAY STAY NORTH. NUMEROUS SHORTWAVES CONTINUE TO TRACK EAST AS UPPER LEVEL LOW REMAINS ACROSS NORTHWESTERN US. AS LOW PUSHES EASTWARD...TRACKS OF WAVES WILL LIKELY GO NORTH OF CWA...BUT MAY SEE DEVELOPMENT FURTHER SOUTH...AND HAVE KEPT POPS ACROSS THE NORTH. SOMEWHAT STRONGER WAVE PUSHES THROUGH FLOW FOR THE WEEKEND...THOUGH UPPER LEVEL LOW WILL PUSH EASTWARD AND SURFACE LOW IN WESTERN PLAINS WILL ALSO LIFT NE AT THIS TIME...AND TIMING AND LOCATION FOR PRECIPITATION CHANCES OVER THE WEEKEND IS VERY MUDDLED. AS UPPER LEVEL LOW PUSHES EAST FRONT WILL DROP ACROSS IOWA WITH PROLONGED PRECIPITATION CHANCE FOR LATE IN THE PERIOD. TEMPERATURES WILL WARM SIGNIFICANTLY UNDER THE RIDGE...WITH SURFACE SOUTHERLY FLOW. HAVE BUMPED TEMPERATURES UP WITH WAA FOR EARLY IN THE PERIOD...THOUGH MIXING MAY BE SOMEWHAT LIMITED. OVERALL...TEMPERATURES WILL WARM WITH SUMMER LIKE READINGS. && .AVIATION...19/18Z ISSUED AT 1239 PM CDT WED JUN 19 2013 VFR CONDITIONS LOOK TO PREVAIL THROUGHOUT THE FORECAST PERIOD. WEAK THETA-E ADVECTION DEVELOPS ACROSS WESTERN IOWA OVERNIGHT TONIGHT AND MAY SPAWN SOME ISOLATED CONVECTION. LEFT MENTION OF ANY THUNDER OUT OF THE TAFS ATTM AS LOW CONFIDENCE IN COVERAGE. OTHERWISE...WINDS WILL INCREASE LATE THURSDAY MORNING AND INTRODUCED GUSTS INTO THE 20-25 KNOT RANGE. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...MS JUN 13 LONG TERM...AWB AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS WICHITA KS
330 PM CDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 329 PM CDT WED JUN 19 2013 FORECAST HIGHLIGHTS FOCUS AROUND THUNDERSTORM CHANCES TONIGHT THROUGH THURSDAY MORNING...WITH HOT AND MOSTLY DRY SUMMER WEATHER LIKELY LATE THIS WEEK THROUGH AT LEAST EARLY TO MID NEXT WEEK. DIFFICULT THUNDERSTORM FORECAST TONIGHT-THURSDAY MORNING. CURRENTLY A WEAK 700-500MB RIPPLE IS ADVANCING EAST ACROSS EASTERN KS. GIVEN THIS FEATURE ALONG WITH THE RELATIVELY UNCAPPED AIRMASS IN PLACE...CANNOT RULE OUT A FEW ISOLATED HIT-AND-MISS THUNDERSTORMS LATE THIS AFTERNOON THROUGH ABOUT SUNSET. NOT ANTICIPATING WIDESPREAD COVERAGE THOUGH. FOCUS THEN TURNS TO LATER TONIGHT WHEN EASTERN FRINGE OF ADVANCING ELEVATED MIXED LAYER APPROACHES FROM THE WEST...DRAMATICALLY INCREASING 800-600MB WARM/MOIST ADVECTION FROM WEST TO EAST...RESULTING IN A CHANCE OF THUNDERSTORMS AFTER 2-3AM WEST OF THE FLINT HILLS. THE HIGHEST CHANCES MAY BE OVER CENTRAL/EAST-CENTRAL KS WHERE NOSE OF MOISTURE TRANSPORT IS POINTING. NAM AND GFS ELEVATED INSTABILITY PROGS INDICATE ~2500 J/KG INSTABILITY FROM PARCELS ROOTED AROUND 800MB...ALONG WITH AROUND 30 KTS OF EFFECTIVE SHEAR...INDICATING STRONG TO SEVERE HAILERS ARE POSSIBLE WITH ANY STORMS THAT CAN FORM. HOWEVER...UNSURE ON HOW WIDESPREAD ACTIVITY WILL BE GIVEN THE CONVECTION-SUPPRESSING AFFECTS OF MID/UPPER RIDGING DEVELOPING ACROSS THE REGION OVERNIGHT...WHICH MAY BE A REASON WHY THE LATEST HRRR AND KF NAM STRUGGLE IN DEVELOPING OVERNIGHT CONVECTION. AGAIN...HIGHEST POTENTIAL MAY REMAIN OVER CENTRAL/EAST-CENTRAL KS AND POINTS NORTH. NEVERTHELESS...HELD ONTO MODEST CHANCE POPS GIVEN STRENGTH OF ISENTROPIC ASCENT/MOISTURE TRANSPORT. ANTICIPATING ACTIVITY TO FESTER MUCH OF THU MORNING EAST OF I-135...AND POSSIBLY INTO THE AFTERNOON EAST OF THE FLINT HILLS. ADK && .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 329 PM CDT WED JUN 19 2013 OTHERWISE...BUILDING MID/UPPER RIDGE WILL LIKELY SUPPRESS WIDESPREAD THUNDERSTORM CHANCES FROM FRIDAY THROUGH AT LEAST EARLY TO MID NEXT WEEK...AND ALLOW ABOVE NORMAL SUMMER HEAT TO BUILD ACROSS THE REGION. CANNOT COMPLETELY RULE OUT A FEW ISOLATED HIT-AND-MISS AFTERNOON-EVENING THUNDERSTORMS FRI-SAT...AS ECMWF HINTS AT SUBTLE WEAKNESSES PROGRESSING OVER THE AREA...BUT THINKING THIS THREAT WILL BE QUITE ISOLATED. OTHERWISE...WITH GFS ENSEMBLES AND OPERATIONAL ECMWF BUILDING RIDGE INTO EARLY/MID NEXT WEEK...CONFIDENCE IS HIGH THAT ABOVE NORMAL SUMMER HEAT IN THE 90S TO LOW 100S WILL PREVAIL REGIONWIDE...WARMEST GENERALLY OVER THE WESTERN HALF OF KS...WITH OVERNIGHT LOWS IN THE 70S ALL AREAS. ADK && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1244 PM CDT WED JUN 19 2013 THE MAIN AVIATION FORECAST CONCERN ARE THE THUNDERSTORM CHANCES OVERNIGHT. VFR CONDITIONS ARE EXPECTED TO PREVAIL...BUT LOW CUMULUS CLOUDS COULD IMPACT THE TERMINALS THIS AFTERNOON. CEILINGS HAVE LIFTED TO 3500+ KFT THIS AFTERNOON AND EXPECT THAT TREND TO CONTINUE. A SLIGHT CHANCE OF THUNDERSTORM EXISTS THIS AFTERNOON AND EARLY EVENING...BUT CONFIDENCE IS LOW ON THAT AND HAVE LEFT OUT ANY MENTION AT THIS TIME AND WILL ALLOW FOR AMENDMENTS IF SOMETHING DEVELOPS. HOWEVER...CONFIDENCE IS HIGHER FOR OVERNIGHT CONVECTION AND HAVE A VCTS AT ALL TERMINALS FOR STORMS. SOUTHERLY WINDS ARE A BIT WEAKER THAN ANTICIPATED...BUT STILL EXPECTING GUSTS THIS AFTERNOON AND THEN AGAIN TOMORROW AFTERNOON WITH MIXING. BILLINGS && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 70 90 73 95 / 40 40 10 10 HUTCHINSON 69 93 73 96 / 40 30 10 10 NEWTON 68 88 73 94 / 40 50 10 10 ELDORADO 69 87 72 92 / 40 40 10 10 WINFIELD-KWLD 70 89 73 93 / 30 40 10 10 RUSSELL 68 97 73 98 / 40 10 10 10 GREAT BEND 68 97 72 97 / 30 10 10 10 SALINA 70 91 74 96 / 50 50 10 10 MCPHERSON 69 91 73 96 / 40 50 10 10 COFFEYVILLE 69 85 73 91 / 30 40 10 10 CHANUTE 68 84 72 90 / 30 40 10 10 IOLA 68 84 71 90 / 30 40 10 10 PARSONS-KPPF 69 84 73 90 / 30 40 10 10 && .ICT WATCHES/WARNINGS/ADVISORIES...NONE. && $$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
303 PM CDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 301 PM CDT WED JUN 19 2013 19Z WATER VAPOR IMAGERY SHOWS A CLOSED UPPER LEVEL LOW OVER THE PACIFIC NORTHWEST WITH A SHORTWAVE ROTATING THROUGH THE TROUGH OVER THE GREAT SALT LAKE. DOWNSTREAM THERE WAS A BROAD UPPER LEVEL RIDGE OVER THE PLAINS WITH A WEAK DISTURBANCE NEAR THE MIDDLE MO RIVER VALLEY MOVING EAST. AT THE SURFACE...A TROUGH OF LOW PRESSURE WAS GRADUALLY DEEPENING ALONG THE LEE OF THE CENTRAL ROCKIES. THIS HAS ALLOWED FOR SOUTHERLY WINDS TO INCREASE. ANY REMNANT OUTFLOW BOUNDARIES FROM EARLY THIS MORNING HAVE BECOME ILL-DEFINED. FOR LATE THIS AFTERNOON AND THIS EVENING...LAPS DATA AND RAP ANALYSIS SHOWS A CONDITIONALLY UNSTABLE AIRMASS OVER THE FORECAST AREA WITH CAPE VALUES AROUND 2000 J/KG...AND VERY LIMITED INHIBITION LEFT. REALLY THE ONLY THING NEEDED FOR CONVECTION IS SOME SORT OF LIFT TO GET PARCELS MOVING UP TO BECOME POSITIVELY BUOYANT. LOW LEVEL CONVERGENCE APPEARS TO BE RELATIVELY WEAK WITH RAP PROGS NOT SHOWING MUCH INCREASE IN LOW LEVEL CONVERGENCE THROUGH SUNSET. WITH NO REAL LARGE SCALE FORCING TO SPEAK OF...THINK CONVECTION IS LIKELY TO BE ISOLATED IF IT DOES DEVELOP. THERE IS SOME SIGNS OF VERTICAL DEVELOPMENT IN THE CU FIELD ACROSS SOUTHEAST NEB. IF A STORM IS ABLE TO DEVELOP AN OUTFLOW...THE GUST FRONT COULD BE ENOUGH LIFT FOR FURTHER DEVELOPMENT. OTHERWISE THINK THE BETTER CHANCES FOR PRECIP WILL BE LATE TONIGHT AND THROUGH THE MORNING THURSDAY. MOST GUIDANCE SHOWS DECENT MID LEVEL THETA-E ADVECTION WITH THE LOW LEVEL JET INCREASING OVER CENTRAL KS. FORECAST SOUNDINGS SHOW INCREASING MOISTURE ALONG THIS GRADIENT AS MID LEVEL LAPSE RATES STEEPEN TO AROUND 7 C/KM. THEREFORE THERE COULD BE SOME ELEVATED STORMS DEVELOP OVERNIGHT AND MOVE ACROSS EASTERN KS THROUGH THE MORNING THURSDAY. LOW CONFIDENCE IN LOCATION OF THE ELEVATED DEVELOPMENT AND WHERE IT MIGHT TRACK PRECLUDE INCREASING POPS FROM THE PREV FORECAST. SO HAVE CONTINUED WITH 40 TO 50 PERCENT CHANCES INTO THURSDAY MORNING. THINK IF ELEVATED STORMS FORM...THAT THE RESULTING MCS SHOULD BE MOVING OFF TO THE SOUTHEAST OR DIMINISHING WITH THE WEAKENING OF THE LOW LEVEL JET BY THE AFTERNOON AND THE POP FORECAST REFLECTS A DOWNWARD TREND IN CHANCES THROUGH THE AFTERNOON. SOUTHERLY WINDS AND SOME MODEST MIXING OF THE BOUNDARY LAYER SHOULD KEEP LOWS TONIGHT IN THE UPPER 60S TO AROUND 70. HIGHS THURSDAY MAY BE A LITTLE MORE TRICKY AS THE MODELS SHOW WEAK MIXING OF THE BOUNDARY LAYER DUE TO COLD POOL PUT DOWN BY THE NOCTURNAL CONVECTION. EVEN IF THERE ARE STORMS...DO NOT THINK THEY WILL PERSIST FOR THE WHOLE DAY AND WE SHOULD STILL SEE SOME GOOD INSOLATION IN THE AFTERNOON WITH SOUTH WINDS INCREASING. THEREFORE HAVE HIGHS FOR THURSDAY IN THE MID 80S ACROSS EAST CENTRAL KS WHERE CLOUDS AND PRECIP COULD POTENTIALLY HANG ON LONGER IN THE MORNING...TO AROUND 90 IN NORTH CENTRAL KS WHERE SUNSHINE SHOULD BREAK OUT EARLIER IN THE DAY. WOLTERS .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 301 PM CDT WED JUN 19 2013 THURSDAY NIGHT AND FRIDAY...SOME CONCERN AS TO CONVECTION REDEVELOPING LATE THURSDAY NIGHT/EARLY FRIDAY MORNING. THURSDAY AFTERNOON THUNDERSTORM COMPLEX EXPECTED TO DEVELOP ALONG SFC WARM FRONT DRAPED OVER CENTRAL NEBRASKA AND WESTERN IOWA. NAM FORECASTED CONVECTIVELY GENERATED COLD POOL MAY PUSH FRONTAL BOUNDARY SOUTH POTENTIALLY OVER SOUTHERN NEBRASKA/NORTHEAST KANSAS BY FRIDAY MORNING. 305K-320K ISENTROPIC LIFT...55KT LLJ AND SOME MID-LEVEL FRONTOGENETICAL FORCING COULD BE ENOUGH TO PROMOTE REDEVELOPMENT OF CONVECTION MAINLY OVER THE FAR NORTHEASTERN SECTIONS OF THE STATE. UPPER LEVEL FORCING IS LACKING HOWEVER...LEAVING REDUCED CONFIDENCE. LEFT FRIDAY AFTERNOON DRY ATTM. HOWEVER...IF CONVECTION DEVELOPS DURING THE EARLY MORNING HOURS...OUTFLOW BOUNDARIES MAY STILL BE PRESENT DURING THE AFTERNOON ACROSS THE CWA. WITH A H5 SHRTWV PROGGED TO ENTER THE STATE FRIDAY AFTERNOON...THIS MAY BE ENOUGH TO REFIRE CONVECTION DURING THE AFTERNOON HOURS. TEMPERATURES WILL BE ON THE INCREASE OVER THE COMING WEEK AS LARGE UPPER LEVEL RIDGE BEGINS TO BUILD INTO THE CENTRAL U.S. HEAT INDICES COULD REACH OVER 100 FRIDAY AFTERNOON. FRIDAY NIGHT THROUGH THE REST OF THE WEEK...RIDGE CONTINUES TO BROADEN ACROSS THE PLAINS ON SATURDAY WITH THE RIDGE AXIS EXTENDING FROM EASTERN COLORADO/WESTERN KANSAS THROUGH NORTHEAST KANSAS AND INTO THE UPPER MIDWEST. SLIGHT CHANCES FOR THUNDERSTORMS WILL BE POSSIBLE ALONG THE NORTHERN SIDE OF THE RIDGE ON SUNDAY. CHANCES INCREASE FOR LOCATIONS NORTH OF I70 SUNDAY NIGHT AS AN H5 SHRTWV TRAVELS NORTHEAST ALONG THE NORTHERN PERIPHERY OF THE RIDGE. COLD FRONT TRIES TO PUSH SOUTHEAST INTO KANSAS ON TUESDAY...BUT UPPER LEVEL SUPPORT FOR THE FRONT MOVES INTO CANADA BY MONDAY AFTERNOON. OTHERWISE...CENTRAL PLAINS RIDGE BROADENS AND COVERS MUCH OF THE CONUS BY TUESDAY. RIDGE BEGINS TO AMPLIFY OVER THE WESTERN U.S. BY WEDNESDAY AFTERNOON SETTING UP THE SUMMER TIME PATTERN OF NORTHWEST FLOW OVER THE CENTRAL PLAINS. HIGHS WILL BE IN THE LOW TO MID 90`S...AND LOWS WILL BE IN THE 60`S AND 70`S. BYRNE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1240 PM CDT WED JUN 19 2013 BECAUSE THERE IS NO FORCING OR SURFACE FEATURE FOR CONVECTION TO FORM...THINK ANY DIURNALLY DRIVEN STORMS WILL BE ISOLATED IN COVERAGE AND HAVE REMOVED THE VCTS FROM THIS AFTERNOON SINCE PREDICTABILITY IS VERY LOW AT THIS POINT. THERE DOES APPEAR TO BE SOME THETA-E ADVECTION OVERNIGHT WITH MID LEVEL LAPSE RATES AROUND 7 C/KM. THIS MAY BE ENOUGH FOR ELEVATED STORMS TO DEVELOP AFTER 06Z. CONFIDENCE IS MARGINAL...BUT WITH ALL THE GUIDANCE SHOWING SOME PRECIP...WILL INCLUDE A VCTS MENTION THROUGH THE MORNING THURSDAY. OTHERWISE ANTICIPATE CONDITIONS TO REMAIN VFR WITH CU FIELD FORMING AROUND 4 KFT. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...WOLTERS LONG TERM...BYRNE AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS WICHITA KS
1245 PM CDT WED JUN 19 2013 .UPDATE... ISSUED AT 1244 PM CDT WED JUN 19 2013 UPDATED THE FORECAST FOR CURRENT TRENDS...ESPECIALLY REGARDING PRECIPITATION POTENTIAL. HAVE DECREASED CHANCES FOR PRECIPITATION DURING THE AFTERNOON HOURS. DID KEEP IN A SLIGHT CHANCE...WITH THE UPPER PV ENERGY MOVING OVER THE STATE AND THE MOISTURE ABUNDANCE...CANNOT RULE OUT A THUNDERSTORM DEVELOPING IN THE WARM AIR ADVECTION SCHEME...BUT CONFIDENCE IS NOT HIGH ON ORGANIZED AND WIDESPREAD CONVECTION THROUGH THE REMAINDER OF THE AFTERNOON. FEEL BETTER CHANCES WILL BE OVERNIGHT...AND WILL LET AFTERNOON FORECAST TOUCH ON THAT. BILLINGS && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 330 AM CDT WED JUN 19 2013 TOUGH FORECAST WAS MADE EVEN MORE DIFFICULT DUE TO THE UNAVAILABILITY OF HRRR/00 UTC ECMWF AND RUC AFTER 0600 UTC DUE TO PROBLEMS UPSTREAM. NONE OF THE REMAINDER OF AVAILABLE GUIDANCE HAD MUCH OF A HANDLE ON ONGOING CONVECTION. NAM WAS PARTICULARLY SUSPECT...ESPECIALLY WITH INITIALIZATION OF 850MB MOISTURE. BASED ON 0000 UTC RADIOSONDE OBSERVATION AND OBSERVATIONAL DATASETS... SEE LITTLE REASON WHY HIGH PLAINS CONVECTION WILL NOT CONTINUE TO ROLL EAST DURING THE DAY AIDED BY WARM AIR ADVECTION...INFLUX OF MOISTURE AND SHORTWAVE. EFFECTS ON TEMPERATURES/WINDS DURING THE DAY WILL BE DIFFICULT TO PIN DOWN. THINKING THAT PRECIPITATION WILL TRANSITION TO EASTERN HALF BY LATE AFTERNOON...WITH LULL IN THE WESTERN HALF AROUND SUNSET. SEE NO REASON WHY STORMS WILL NOT DEVELOP OVER THE HIGH PLAINS AGAIN TONIGHT AND ROLL EAST. THU REMAINS PROBLEMATIC...AS IT IS UNCLEAR HOW WIDESPREAD CONVECTION WILL BE OR LOW LONG IT WILL LINGER. LARGE POTENTIAL FOR ERROR ON ALL FACETS OF THIS FORECAST. HAVE LEANED A BIT TOWARDS THE GFS WHICH WAS THE LEAST WRONG GUIDANCE OUT OF THE BOX. HAVE STAYED THE COURSE WITH DRY/WARMER/WINDIER CONDITIONS ON FRIDAY. -HOWERTON .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 330 AM CDT WED JUN 19 2013 THE WARMING TREND WILL CONTINUE INTO THE WEEKEND AS RIDGE BUILDS. SOME HINT ON THE LATEST AVAILABLE GUIDANCE THAT FRONT MAY SAG CLOSE ENOUGH TO BRING SMALL CHANCES FOR PRECIPITATION ON SUN/SUN NIGHT. NOT OVERLY OPTIMISTIC ABOUT THESE CHANCES BUT IN ABSENCE OF 0000 UTC ECMWF WILL NOT MAKE SIGNIFICANT CHANGES. HAVE HEDGED TEMPERATURES UP A BIT ABOVE INITIALIZATION GRIDS BASED ON LAST WARM PERIOD AND BEST GUIDANCE AT THESE TIME RANGES. TEMPERATURES IN TRIPLE DIGITS APPEAR PROBABLE IN CENTRAL KS BY EARLY NEXT WEEK. -HOWERTON && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1244 PM CDT WED JUN 19 2013 THE MAIN AVIATION FORECAST CONCERN ARE THE THUNDERSTORM CHANCES OVERNIGHT. VFR CONDITIONS ARE EXPECTED TO PREVAIL...BUT LOW CLUMULUS CLOUDS COULD IMPACT THE TERMINALS THIS AFTERNOON. CEILINGS HAVE LIFTED TO 3500+ KFT THIS AFTERNOON AND EXPECT THAT TREND TO CONTINUE. A SLIGHT CHANCE OF THUNDERSTORM EXISTS THIS AFTERNOON AND EARLY EVENING...BUT CONFIDENCE IS LOW ON THAT AND HAVE LEFT OUT ANY MENTION AT THIS TIME AND WILL ALLOW FOR AMENDMENTS IF SOMETHING DEVELOPS. HOWEVER...CONFIDENCE IS HIGHER FOR OVERNIGHT CONVECTION AND HAVE A VCTS AT ALL TERMINALS FOR STORMS. SOUTHERLY WINDS ARE A BIT WEAKER THAN ANTICIPATED...BUT STILL EXPECTING GUSTS THIS AFTERNOON AND THEN AGAIN TOMORROW AFTERNOON WITH MIXING. BILLINGS && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 87 70 90 73 / 30 40 30 10 HUTCHINSON 86 69 91 72 / 30 50 20 10 NEWTON 86 68 89 72 / 40 40 30 10 ELDORADO 86 69 88 73 / 30 40 40 10 WINFIELD-KWLD 87 70 89 73 / 30 40 30 10 RUSSELL 87 68 94 71 / 50 50 10 10 GREAT BEND 87 68 93 72 / 50 50 10 10 SALINA 88 70 90 75 / 40 50 30 10 MCPHERSON 86 69 90 72 / 40 50 30 10 COFFEYVILLE 88 69 86 73 / 20 30 30 10 CHANUTE 87 68 84 72 / 20 30 30 10 IOLA 87 68 83 71 / 20 30 30 10 PARSONS-KPPF 87 69 84 72 / 20 30 30 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1131 AM MDT WED JUN 19 2013 .SHORT TERM...(TODAY THROUGH FRIDAY NIGHT) ISSUED AT 402 AM MDT WED JUN 19 2013 MAIN FORECAST PROBLEM THUNDERSTORM COVERAGE/CHANCES THROUGH PERIOD WITH HOW HOT DOES IT GET THURSDAY AND FRIDAY. SATELLITE CONTINUING TO SHOW AN AMPLIFIED/BLOCKY/COMPLICATED UPPER FLOW FROM THE EASTERN PACIFIC INTO THE CENTRAL PORTION OF THE COUNTRY. UPPER LOW HAS MOVED CLOSER TO THE PACIFIC NORTHWEST WITH WEST TO SOUTHWEST FL0W ALOFT SPREADING ACROSS OUR AREA. COLD FRONT REMAINS WELL TO OUR SOUTH AND IS DRAPED UP AGAINST THE COLORADO FRONT RANGE. LARGE COMPLEX OF THUNDERSTORMS HAS PRODUCED A SIGNIFICANT COLD POOL AND HAS SENT UP MESOSCALE/CONVERGENT BOUNDARIES ACROSS DIFFERENT PORTIONS OF THE REGION. MODELS INITIALIZED FINE AT JET LEVEL. THE NAM/ECMWF LOOKED TO HAVE INITIALIZED THE WORST ON THE MID LEVELS WITH THE UKMET/CANADIAN/GFS/SREF DOING ABOUT THE SAME. NAM WAS A LITTLE WARM AT 700 MB WITH THE GFS AND UKMET BETTER. SREF AND GFS WERE DOING LITTLE BETTER THAN THE NAM AND CANADIAN ON THE LOW LEVEL THERMAL FIELD. TODAY/TONIGHT...DUE TO THE OVERNIGHT THUNDERSTORM COMPLEX THAT WENT THROUGH...MESOSCALE BOUNDARIES/CONVERGENCE DO ABOUND. SATELLITE AND UPPER AIR ANALYSIS SHOWING A COUPLE OF WEAK SHORTWAVES TO OUR WEST PLUS A WARMER AND DRIER MID LEVEL AIR MASS/EML MOVING IN FROM THE WEST. NEAR 12Z THE LEFT FRONT QUADRANT OF SOUTHERN JET WILL BE AFFECTING THE SOUTHWEST PORTION OF THE AREA. IT STAYS NEAR THE SOUTHERN PORTION OF THE AREA THROUGH AS SLOWLY PROGRESSES SOUTH AWAY FROM THE AREA. VERY UNCERTAIN PRECIPITATION FORECAST FOR THE DAY...ESPECIALLY THIS MORNING...WITH MESOSCALE FEATURES BEING A BIG INFLUENCE. CONVECTIVE CIRCULATION IS LOCATED OVER THE EASTERN PORTION OF THE AREA. ONE OF THOSE OUTFLOW BOUNDARIES LIES ACROSS THE NORTHEAST PORTION. ALL MODELS ESPECIALLY THE RAP REDEVELOPS A SIGNIFICANT PRECIPITATION AREA OVER THE NORTHEAST TO EAST PORTION OF THE AREA THIS MORNING. CONSIDERING THAT THE RAP HAS BEEN CONSISTENT FOR A COUPLE OF RUNS... MATCHES UP WITH WHERE THE BOUNDARY IS RIGHT NOW AND THAT THUNDERSTORMS HAVE REDEVELOPED ALREADY IN THE SAME GENERAL AREA... WILL RAISE POPS TO A HIGH CHANCE THIS MORNING AND CONTINUE TO MONITOR. THAT CIRCULATION AND PRECIPITATION LOOK TO EXIT THE AREA AROUND THE MIDDLE OF THE DAY. THE AIR MASS LOOKS TO RELOAD WITH EMPHASIS SHIFTING BACK TO THE WEST. SURFACE TROUGH STILL REMAINS TO THE WEST OF THE AREA. WHAT LOOKS TO BE A DRYLINE SETS UP OVER THE FAR WEST WITH THE INSTABILITY AXIS SETTING NEAR THE COLORADO AND KANSAS BORDER. THE FAR WESTERN MAY BE CAPPED THIS AFTERNOON. SHORTWAVE TROUGH MOVES IN FROM THE WEST AND EXPECT THUNDERSTORMS TO DEVELOP NEAR OR JUST TO THE EAST OF THE COLORADO BORDER. THESE STORMS SHOULD PROGRESS TO THE EAST THROUGH THE NIGHT AS THE SHORTWAVE MOVES TOWARD THE EAST AND THE LOW LEVEL JET DEVELOPS IN THE EASTERN THIRD. DO NOT HAVE A GOOD FEEL WITH THE HIGH TEMPERATURES. IT IS POSSIBLE WITH THE WET GROUND AND ONGOING CLOUD COVER AND PRECIPITATION COULD CAUSE TEMPERATURES TO BE COOLER...ESPECIALLY IN THE EAST. THURSDAY/THURSDAY NIGHT...INTERESTING FORECAST FOR THIS DAY. 700 MB TEMPERATURES REMAIN RATHER HIGH THROUGH THE DAY...WITH THE LOWEST AND CAP BREAKABLE TEMPERATURES IN THE NORTHERN AND EASTERN PORTIONS OF THE AREA. BY LATE AFTERNOON...EITHER A WEAK COOL FRONT OR SURFACE TROUGH SAGS INTO THE NORTHERN PORTION OF THE AREA WITH WHAT LOOKS TO BE A DRYLINE JUST TO THE WEST OF THE SOUTHEAST CORNER. AT THE SAME TIME A SHORTWAVE TROUGH APPROACHES FROM THE SOUTHWEST. ALL THESE FEATURES PROGRESS NORTH AND EAST THROUGH THE EVENING. BY LATE IN THE AFTERNOON A WEAK LEFT FRONT QUADRANT LOOKS TO BE JUST SOUTH OF THE FORECAST AREA. THIS LIFT MOVES SLOWLY NORTH THROUGH THE EVENING AND WILL BE AFFECT THE SOUTHEAST QUARTER BY LATE IN THE NIGHT. MODELS ARE GENERATING SOME LIGHT QPF EVEN WITH WHAT LOOKS TO BE A DEEP DRY LAYER AND HIGH BASES. BELIEVE THERE IS ENOUGH HERE TO INCLUDE A LOW SLIGHT CHANCE. HOWEVER...COULD SEE THINGS TOTALLY CAPPED OR BE ABLE TO BREAK LOOSE. ALONG AND NORTH OF THE BOUNDARY THE TEMPERATURES WILL BE SLIGHTLY COOLER...IN THE 90S. SOUTH THE BOUNDARY IT WILL BE NEAR 100 DEGREES. MODELS DO DISAGREE WITH HOW FAR SOUTH TO TAKE THE BOUNDARY. CONSIDERING THE FLOW ALOFT AND THE AIR MASS LIKE THE BOUNDARY BEING FURTHER NORTH. FRIDAY/FRIDAY NIGHT...THE CANADIAN AND ECMWF KEEP A WEAK LEFT FRONT QUADRANT OF THE JET NEAR/OVER THE EASTERN AND CENTRAL PORTION OF THE AREA THROUGH THE DAY. VERY SIMILAR SETUP TO THE DAY BEFORE EXCEPT MOST OF THE WEST AND CENTRAL PORTIONS DO LOOK CAPPED DESPITE THE SURFACE TROUGH AND DRYLINE NEAR THE SAME PLACE. THE EASTERN THIRD HAS THE LOWER 700 MB TEMPERATURES WITH THE INSTABILITY AXIS AND BEST MID LEVEL MOISTURE IN THE SAME AREA. AT THE SAME TIME A SHORTWAVE TROUGH IS COMING ACROSS. LIKED WHAT THE PREVIOUS SHIFT HAD IN THERE FOR A SLIGHT CHANCE AND ONLY MADE A SLIGHT ADJUSTMENT TO THE AREA FOR THE AFTERNOON AND EVENING HOURS. ONCE AGAIN HIGH TEMPERATURES WILL BE DETERMINED BY WHERE THE BOUNDARY SETS UP. MODEL DATA SAYS THE BOUNDARY WILL BE A LITTLE FURTHER NORTH AND SO WILL THE HOT TEMPERATURES AND TRENDED THE MAXES IN THAT DIRECTION. .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 230 AM MDT TUE JUN 19 2013 STRONG SOUTHWEST FLOW ALOFT AT 500 MB WILL PERSIST THROUGHOUT THE DAY SATURDAY AS MERIDIONAL FLOW PATTERN EXISTS OVER THE CENTRAL PLAINS. INSTABILITY WILL BE PRESENT IN THE FLOW AS EMBEDDED SHORTWAVE TROUGHS ENTER INTO OUR FORECAST AREA. AN UPPER LEVEL LOW WILL PROGRESS WESTWARD OVER THE NORTHERN HIGH PLAINS AS BLOCKING RIDGE OVER THE SOUTHERN PLAINS STRENGTHENS SATURDAY EVENING INTO SUNDAY. STRONGEST UPPER LEVEL JET WILL STAY IN THE NORTHERN PLAINS ALONG WITH STRONGEST POSITIVE VORTICITY VALUES...HOWEVER SOME POCKETS OF POSITIVE VORTICITY WILL ENTER THE TRI STATE AREA FOR SUNDAY AFTERNOON AND EVENING. THE TROUGH BECOMES NEGATIVELY TILTED AS FLOW PATTERN RETURNS TO ZONAL FLOW FOR SUNDAY EVENING AND MONDAY. THE RIDGE TO THE SOUTH WILL CONTINUE TO STRENGTHEN AND MOVE INTO THE CENTRAL PLAINS FOR TUESDAY...AND JET STREAM WILL STAY WELL TO THE NORTH OF THE AREA FOR THE REST OF NEXT WEEK. 850 MB JET SPEEDS ARE VERY STRONG DUE TO NOCTURNAL EFFECT FOR OVERNIGHT SATURDAY AND SUNDAY TOWARD WEST CENTRAL KANSAS...WHICH COULD PROVIDE SOME UNSTABLE WEATHER WITH UPPER LEVEL SHORTWAVE FORCING. ONCE RIDGE BUILDS INTO THE REGION...THE JET SPEEDS WILL DECREASE AND BECOME CALM FOR THE REST OF NEXT WEEK. AT THE SURFACE...STRONG WARM AIR ADVECTION WILL BE PRESENT ACROSS THE AREA WITH TEMPERATURES REACHING THE MID TO UPPER 90S FOR THE WEEKEND. 850 MB TEMPERATURES ARE ALSO WARM...WITH VALUES IN THE MID 80S SATURDAY AND SUNDAY. THETA E VALUES ARE MARGINAL AT 850 AND AT THE SURFACE...WITH HIGHER VALUES TOWARD CENTRAL KANSAS. DEW POINTS WILL BE IN THE MID 50S ACROSS THE REGION...WITH A 30 DEGREE DRY LINE GRADIENT PRESENT IN THE WESTERN CWA. ALTHOUGH BEST SURFACE BOUNDARY EXISTS FOR THE AREA SATURDAY AND SUNDAY...INSTABILITY PARAMETERS ARE MARGINAL AT BEST. THERE ARE SOME CHANCES FOR THUNDERSTORM DEVELOPMENT SATURDAY AND SUNDAY AFTERNOON...BUT THE BEST CHANCE IS TO THE EAST TOWARDS MORE UNSTABLE ENVIRONMENT IN CENTRAL KANSAS. STRONG SOUTH/SOUTHWEST FLOW WILL RETURN TO THE REGION FOR MONDAY AFTERNOON AND FOR THE REST OF THE WEEK...BRINGING WARM AIR AND DRY CONDITIONS TO MUCH OF THE AREA. AFTERNOON AND EVENING THUNDERSTORMS WILL DEVELOP ACROSS MUCH OF THE AREA FOR THE WEEKEND AS WARM FRONT INCREASES TEMPERATURES. MORE STABLE UPPER LEVEL AIR WILL MOVE INTO THE HIGH PLAINS REGION FOR NEXT WEEK...PROVIDING DRY CONDITIONS AND TEMPERATURES THAT MAY REACH NEAR 100. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1131 AM MDT WED JUN 19 2013 VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD AT BOTH GLD AND MCK. CLOUDS HAVE DEVELOPED AT BOTH SITES AND ARE EXPECTED TO PERSIST THROUGH THE LATE AFTERNOON. WINDS WILL BE THE PRIMARY AVIATION CONCERN DURING THIS TAF PERIOD...WITH BREEZE SOUTHERLY WINDS OF 20KTS GUSTING TO AROUND 30KTS...KEEPING UP THROUGH THE EVENING AS A 40-50KT LOW LEVEL JET DEVELOPS OUT OF THE SOUTH-SOUTHWEST...WHICH MAY PROMPT A LLWS GROUP TO BE ADDED TO THE TAF. SOME THUNDERSTORMS ARE POSSIBLE LATE THIS AFTERNOON...BUT CHANCES ARE FAIRLY LOW SO DID NOT INCLUDE ANY MENTION IN TAF. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...MK AVIATION...JJM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
430 PM EDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 429 PM EDT WED JUN 19 2013 WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW THROUGH THEN NRN GREAT LAKES BETWEEN A TROUGH OVER ERN CANADA AND A RIDGE OVER THE PLAINS. SCT SHRA AND ISOLD TSRA HAD DEVELOPED NEAR CYRL ON THE TAIL OF A SHORTWAVE TROUGH THROUGH NW ONTARIO. AN UPSTREAM SHRTWV WAS ALSO LOCATED OVER ERN SD. AT THE SFC...SRLY WINDS HAD INCREASED BETWEEN HIGH PRES OVER THE ERN GREAT LAKES AND A TROUGH EXTENDING INTO ND FROM LOW PRES W OF JAMES BAY. LOW LEVEL MOISTURE WAS ONLY SLOWLY INCREASING WITH DEWPOINTS CLIMBING TO NEAR 50F OVER THE WEST. TONIGHT...EVEN THOUGH THE FORCING WITH THE NW ONTARIO SHRTWV WILL REMAIN NORTH OF THE CWA...MODELS SUGGEST THAT THE SHRA AND POSSIBLY SOME TSRA WILL DEVELOP LATER THIS EVENING NW OF LAKE SUPERIOR AND SLIDE INTO THE WRN CWA OVERNIGHT. MOISTURE TRANSPORT AND THE POSITION OF THE 850-700 MB FRONTAL ZONE FAVORS GREATER PCPN CHANCES/COVERAGE OVER NW LAKE SUPERIOR INTO MAINLY THE NW CWA. MUCAPE VALUES ARE EXPECTED TO BE HIGH ENOUGH FOR ELEVATED TSRA DEVELOPMENT. THURSDAY...THE COMBINATION OF INCREASING MOISTURE TRANSPORT...DAYTIME HEATING AND THE SD SHRTWV SHOULD BRING INCREASING SHRA/TSRA COVERAGE ACROSS THE CWA. ALTHOUGH INSTABILITY WILL BE MARGINAL FOR STRONGER STORMS WITH MLCAPE VALUES INTO THE 500-1000 J/KG RANGE...AND A RELATIVELY NARROW CAPE PROFILE....SOME STORMS WITH SMALL HAIL AND GUSTY WINDS TO 35 MPH MAY BE POSSIBLE. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 429 PM EDT WED JUN 19 2013 CONVECTION WILL MAKE FOR A VERY TRICKY AND UNCERTAIN FORECAST THU NIGHT THROUGH AT LEAST THE WEEKEND. AN UPPER RIDGE WILL MOVE E INTO THE AREA THU NIGHT THROUGH THE MIDDLE OF NEXT WEEK. AT THE SFC...A WEAK LOW WILL REMAIN FAIRLY STATIONARY OVER THE CENTRAL AND NRN PLAINS...LEAVING A WARM FRONT ACROSS OR NEAR THE CWA THROUGH THIS WEEKEND. CONFIDENCE IS VERY LOW /AS WITH MOST CONVECTIVE SITUATIONS/ WITH THE EXACT TRACK/TIMING OF ANY CONVECTIVE COMPLEXES MOVING ALONG OR NEAR THE WARM FRONT. MODELS SHOW MULTIPLE SCENARIOS FOR CONVECTIVE DEVELOPMENT AND MOVEMENT...INCLUDING MOVING THE WARM FRONT N OF THE CWA KEEPING THE BULK OF CONVECTION N OF THE CWA...TO HAVING THE WARM FRONT STALL S OF THE CWA WHICH WOULD KEEP MOST OF THE CONVECTION S. OVERALL...THE BULK OF THE MODELS SHOW CONVECTIVE COMPLEXES MOVING OVER THE CWA...SO WILL CONTINUE TO PUT THAT INTO THE FORECAST AS HAS BEEN DONE BY PREVIOUS SHIFTS. SOME OF THE THUNDERSTORMS COULD VERY WELL BE STRONG WITH LARGE HAIL AND DAMAGING WINDS THE PRIMARY THREATS...BUT CONFIDENCE IS STILL TOO LOW TO INCORPORATE THAT INTO THE FORECAST BUT WILL CONTINUE SOME MENTION OF STRONGER STORMS IN THE HWO. SPC HAS AREAS ALONG THE BORDER UNDER A SLIGHT RIGHT...AND GENERALLY AGREE WITH THAT GIVEN THE LOCATION OF THE GREATEST INSTABILITY. MODELS SHOW UP TO 4500J/KG /GFS/ OF SBCAPE NOSING INTO WRN UPPER MI FRI AFTERNOON...BUT THAT IS THE HIGHEST AMOUNT AND LOOKS LIKE LOW LEVELS ARE OVERLY MOIST IN THE MODEL. THE NAM IS ANOTHER MODEL THAT SEEMS TOO HIGH ON LOW LEVEL MOISTURE AND SBCAPE AT UP TO 3500J/KG ON FRI. ECMWF AND GEM SEEM MORE REASONABLE AT 1000-1500J/KG ALONG THE WI BORDER SO WILL FAVOR THAT SOLUTION. COULD HAVE DAYTIME CONVECTION BREAK OUT OVER WRN AND CENTRAL UPPER MI...BUT MOST LIKELY SCENARIO AT THIS POINT CONTINUES TO BE CONVECTION FORMING UPSTREAM AND MOVING TO THE ESE ALONG THE FORWARD PROPAGATING CORFIDI VECTORS AND INSTABILITY GRADIENT FRI. ANOTHER RISK FACTOR WILL BE HEAVY RAIN WITH ANY THUNDERSTORMS AS PWATS WILL BE 150-200 PERCENT OF NORMAL. SAT AND SUN LOOK SIMILAR TO FRI...WITH SIMILAR UNCERTAINTY DUE TO CONVECTIVE UNCERTAINTY. IN FACT...SIMILAR CONDITIONS SHOULD BE OBSERVED INTO THE MIDDLE OF NEXT WEEK...BUT CONFIDENCE INCREASES TOO MUCH MON-WED TO TALK TOO MUCH ABOUT THIS TIME FRAME. LOOKING AT TEMPS...SHOULD SEE SFC TEMPS INCREASE SLIGHTLY FROM DAY TO DAY THROUGH THE FORECAST PEROID WITH HIGHS IN THE 80S ACROSS A LARGE PART OF UPPER MI BY SUN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 141 PM EDT WED JUN 19 2013 VFR CONDITIONS ARE EXPECTED TO PREVAIL THIS AFTERNOON INTO THIS EVENING EVEN AS LOW LEVEL MOISTURE INCREASES WITH SRLY FLOW. BY LATE TONIGHT INTO THURSDAY MORNING...THE COMBINATION OF A SHORTWAVE TROUGH AND AN ADVANCING WARM FRONT WILL SUPPORT SOME SHOWERS THAT WILL SPREAD INTO UPPER MICHIGAN. MAINLY VFR CONDITIONS SHOULD STILL PERSIST...BUT IF A MORE PERSISTENT AREA OF RAIN DEVELOPS CIGS COULD DROP INTO THE MVFR RANGE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 429 PM EDT WED JUN 19 2013 WINDS SHOULD REMAIN BELOW 25KTS THROUGH THE PERIOD...WITH RELATIVELY LOW WAVES. THE MAIN HAZARD WILL BE STRONGER WINDS/HAIL/LIGHTNING WITH ANY THUNDERSTORMS MOVING ACROSS LAKE SUPERIOR FROM LATE TONIGHT THROUGH INTO EARLY NEXT WEEK. AREAS OF FOG THAT DEVELOP AS A RESULT OF INCREASED MOISTURE AND SHOWER ACTIVITY MAY ALSO BECOME LOCALLY DENSE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1257 PM CDT WED JUN 19 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 410 AM CDT WED JUN 19 2013 CIRRUS SHIELD NOTED ON IR SATELLITE ENTERING FAR WESTERN MN. SHIELD IS JUST AHEAD OF DEEPENING SURFACE CYCLONE ABOVE EASTERN MONTANA. THIS FEATURE WILL BE EJECTED OUT OF 50H TROF OVER PACIFIC NW DURING THE NEXT 24 HOURS INTO WESTERN NODAK AND SOUTHERN SASKATCHEWAN. WARM FRONTAL BOUNDARY ATTACHED TO SURFACE CYCLONE WILL BE CATALYST FOR SCATTERED SHOWERS AND ISOLATE THUNDERSTORMS LATE THIS MORNING OVER FAR WESTERN CWA. USED GFS40 THETA E ADVECTION AND HRRR GUIDANCE FOR PLACEMENT AND TIMING OF DAYTIME CONVECTION OVER FA. COULD BE A FEW STRONG TO NEAR SEVERE THUNDERSTORMS THIS AFTERNOON OVER CENTRAL AND PORTIONS OF SW MN TO...AS JOULES INCREASE INTO THE 1500 TO 2500 RANGE. MODERATE 250MB DIVERGENCE COUPLETS ALSO NOTED OVER THESE AREAS ALONG WITH LI`S PLUNGING INTO THE NEGATIVE 4 TO NEGATIVE 8 CATEGORY. ONLY LIMITING FACTOR WOULD BE THICKER CLOUD DECK THEN CURRENT CIRRUS SHIELD PROGGED FOR MUCH OF THE DAYTIME HOURS. PRESENCE AND PROGRESSION OF WARM FRONTAL BOUNDARY DEEPER INTO SOUTHERN HALF OF MN TONIGHT SHOULD PORTEND SLIGHTLY ENHANCED CHANCES FOR CONVECTION...WITH QPF VALUES ALSO RISING NOTICEABLY. COULD BE A QUICK QUARTER INCH TO ONE HALF INCH OF MOISTURE GENERATE FROM CONTINUE SCT ACTIVITY DURING THE OVERNIGHT. 850MB LAPSE RATES AND LI`S WILL ALSO RISE SLIGHTLY OVERNIGHT. MODERATE SOUTHERLY LOW LEVEL JET WILL ALSO FORM BY LATE TONIGHT OVER MUCH OF MN FA ...WITH 25 TO 30KT MAGNITUDES COMMON SOUTH OF A LINE FROM ALEXANDRIA TO OWATONNA. COULD BE ADDITIONAL ISOLATED STRONG TO NEAR SEVERE T-STORMS OVER WESTERN HALF OF FA DURING THE EVENING...SWITCHING TO FAR EAST CENTRAL MN/WEST CENTRAL WI AFTER MIDNIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 410 AM CDT WED JUN 19 2013 WARM AND MOISTURE-RICH PATTERN WILL REMAIN IN PLACE FOR THE END OF THIS WEEK INTO THE START OF NEXT WEEK...INCLUDING PERIODS OF STRONG THUNDERSTORMS AND HEAVY RAIN. AN UPPER LEVEL RIDGE BUILDING OVER THE DAKOTAS AND MN/WI THRU TDA WILL SHIFT TO THE E THRU THU WHILE A LONGWAVE TROUGH DEVELOPS OVER THE NORTHWEST. SEVERAL SHORTWAVE DISTURBANCES RIDING NOT ONLY OVER TOP THE RIDGE BUT ALSO AROUND THE BASE OF THE TROUGH THU INTO FRI WILL WORK WITH AN INCOMING SFC FRONTAL SYSTEM DEVELOPING OVER THE CENTRAL-NRN PLAINS. SOLID SW FLOW WILL BRING NOT ONLY WARMER AIR /WHICH WILL RAISE H5 HEIGHTS TO ENHANCE CAPPING BUT ALSO STRONGER JETTING/ BUT ALSO MOISTURE-RICH AIR /HELPING RAISE PWATS ABOVE 1.50 INCHES AND ENHANCE INSTABILITY/...AND THE SFC FRONTAL WAVES COMBINED WITH UPPER LEVEL DISTURBANCES WILL ALLOW FOR PERIODS OF CONVECTION. THURSDAY CONTINUES TO BE HIGHLIGHTED BY SPC INVOF THE APCHG CDFNT FOR THE WRN HALF OF MN. ONCE THE CAPPING INVERSION IS LOST OVER WRN MN...STRONG MID- AND UPPER-LEVEL JETTING WITH STEEP LAPSE RATES WITHIN A HIGHLY UNSTABLE ENVIRON /INCLUDING DEWPOINTS NEAR- OVER 70 DEGREES/ WILL PROMOTE STRONG TO SEVERE TSTMS CAPABLE OF PRODUCING LARGE HAIL AND DMGG WINDS. THE REGIME THEN TRANSITIONS TO ONE OF HEAVY RAIN OVER THE WEEKEND AS THE SFC LOW PRES SYSTEM OPENS UP AND BECOMES CAUGHT UP IN THE PROLIFIC SWLY FLOW WHILE THE NW UPPER LEVEL TROUGH OPENS TO MORE OF A TROUGH THAN CUTOFF LOW. LONG PLUME OF SLY SFC FLOW WILL AID IN BRINGING MOISTURE WELL N INTO THE UPPER MISS RIVER VALLEY REGION. MODEL QPF CONTINUES TO ADVERTISE BETWEEN 3 AND 6 INCHES OF RAIN FOR THE AREA THROUGH THE WEEKEND...BUT WITH MUCH OF IT CONVECTIVE...TRYING TO PINPOINT WHERE SUCH RAINFALL EVENTS MAY OCCUR IS HIGHLY PROBLEMATIC. STILL...HAVE KEPT HIGH-END CHC POPS GOING IN THE FCST. POPS DIMINISH FOR THE START OF NEXT WEEK AS A MORE ZONAL UPPER LEVEL PATTERN DEVELOPS...KEEPING ANY ORGANIZED LOW PRES SYSTEMS AWAY FROM THE AREA. THAT SAID...SEVERAL MID- AND UPPER-LEVEL SHORTWAVE DISTURBANCES WILL STILL BE CAPABLE OF PRODUCING ISOLD TO SCATTERED CONVECTION AS THE WARM/MOIST AIR WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1250 PM CDT WED JUN 19 2013 THE CU FIELD IS EXPANDING ACROSS THE MN RIVER VALLEY AND A FEW SHOWERS/TSTMS COULD OCCUR THIS AFTERNOON IN THIS AREA AS TEMPS PEAK IN THE UPPER 80S. A FEW ELEVATED SHOWERS/TSTMS MAY ALSO OCCUR IN WEST CENTRAL WI AS MID LEVEL INSTABILITY MOVES THROUGH. THE THREAT FOR SHOWERS AND THUNDERSTORMS WILL INCREASE DURING THE EVENING FOR KAXN AND KRWF WITH SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO THE TWIN CITIES AND WEST CENTRAL WI DURING THE OVERNIGHT HOURS. THE ACTIVITY WILL LINGER OVER EASTERN AREAS THURSDAY MORNING. THERE IS NO REAL FOCUS ON THE SHOWERS AND THUNDERSTORMS TONIGHT/EARLY THURSDAY AND MUCH WILL RELY ON THE DEVELOPMENT OVER THE DAKOTAS LATER THIS AFTERNOON AND TONIGHT. A MUCH BETTER CHANCE FOR STRONG TO SEVERE STORMS WILL EXIST THURSDAY AFTERNOON AND NIGHT ACROSS WESTERN AND SOUTHERN MN AS A FRONTAL BOUNDARY INCHES CLOSER TO THE AREA. LOOK FOR SE WINDS FROM 10 TO 15 KNOTS THIS AFTERNOON WITH SOME GUSTS TO AROUND 20 FOR KAXN AND KRWF. KMSP...VFR EXPECTED THROUGH THE PERIOD. THE BEST CHANCE FOR SHOWERS AND ISOLATED THUNDERSTORMS IS FROM LATE TONIGHT THROUGH THURSDAY MORNING. TEMPORARY DIPS TO MVFR CAN BE EXPECTED IN THE BOUTS OF PRECIPITATION. SE WINDS THIS AFTERNOON AND TONIGHT NEAR 10 KNOTS. /OUTLOOK FOR KMSP/ THU NIGHT...VFR. CHC OF MVFR/TSRA. SE WINDS 10 KTS. FRI...VFR. CHC OF MVFR/TSRA. SE WINDS 10 KTS. SAT...VFR. CHC OF MVFR/TSRA. SE WINDS 8 KTS. SUN...VFR. CHC OF MVFR/TSRA. S WINDS 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...AJZ LONG TERM...JPC AVIATION...RAH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
432 PM CDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 430 PM CDT WED JUN 19 2013 MORE LOW-CONFIDENCE THUNDERSTORM CHANCES ARE THE MAIN CONCERN ESPECIALLY FOR LATE TONIGHT...WITH REASONABLE CONFIDENCE THAT THE THURSDAY DAYTIME HOURS SHOULD HOLD STORM-FREE UNDER A STRENGTHENING CAP. OTHERWISE...HEAT/HUMIDITY THURSDAY IS EXPECTED TO RISE ANOTHER NOTCH ABOVE THAT OF TODAY AS A GRADUAL WARMING TREND CONTINUES. 20Z SURFACE ANALYSIS HIGHLIGHTS A DEEPENING 996 MILLIBAR LOW OVER CENTRAL WY...WHICH HAS TIGHTENED THE CENTRAL PLAINS PRESSURE GRADIENT THUS RESULTING IN SUSTAINED SOUTH-SOUTHEAST WINDS 15-25 MPH THIS AFTERNOON GUSTING 30-35 MPH IN SPOTS. THIS SURFACE LOW HAS DEEPENED IN RESPONSE TO A FAIRLY VIGOROUS...NEGATIVELY TILTED SHORTWAVE TROUGH BARRELING NORTHEAST ACROSS SOUTHERN ID...ALONG THE SOUTHEAST PERIPHERY OF AN EXPANSIVE CLOSED MID LEVEL LOW ANCHORED OVER THE PACIFIC NORTHWEST. CLOSER TO HOME...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA DEPICT MODEST QUASI-ZONAL FLOW...WITH THE MAIN SUBTLE SHORTWAVE TROUGH CURRENTLY EXITING THE CWA EASTWARD...WITH MID LEVEL DRYING NOTED IN ITS WAKE. JUST WITHIN THE PAST HOUR...A FEW SHOWERS/THUNDERSTORMS HAVE FLARED UP JUST EAST OF OUR CWA IN EASTERN NEB...IN CLOSER PROXIMITY TO THIS ADVANCING WAVE AND IN THE PRESENCE OF A WEAKLY CAPPED AIRMASS FEATURING 1500+ J/KG 0-1KM MLCAPE. ACROSS OUR AREA HOWEVER...AT LEAST UP THROUGH NOW...ITS BEEN A RAIN/THUNDER-FREE DAY...UNDER ONLY A FAIR WEATHER CUMULUS FIELD MOST AREAS...AND A BIT MORE MID- LEVEL CLOUD DEVELOPMENT IN THE FAR WEST WITHIN A ZONE OF THETA-E ADVECTION EVIDENT AT 700MB. UNLIKE YESTERDAY AT THIS TIME...THERE IS NO SURFACE FRONT/OUTFLOW BOUNDARY AND NO EVIDENT SUBTLE INCOMING SHORTWAVE TO KICK OFF CONVECTION...AND IT GOES WITHOUT SAYING THAT SEVERAL DETERMINISTIC MODEL QPF FIELDS ENDED UP BEING CONSIDERABLY OVERDONE ON RAIN POTENTIAL TODAY. TEMP-WISE...MOST AREAS ARE HEADED FOR HIGHS BETWEEN 86-91. LOOKING AHEAD THROUGH LATE THIS AFTERNOON INTO TONIGHT...THE BIG PICTURE ALOFT INVOLVES A NORTHWARD BUILDING OF A SOUTH CENTRAL CONUS RIDGE INTO THE CENTRAL PLAINS...WHILE THE STRONG SHORTWAVE TROUGH WELL TO THE NORTHWEST SLIDES UP ACROSS MT. MEANWHILE OVER THE LOCAL AREA...FLOW WILL REMAIN QUASI-ZONAL AS AT LEAST 1-2 MORE VERY SUBTLE DISTURBANCES POSSIBLY PASS EASTWARD ACROSS THE REGION. OF NOTE...PRONOUNCED WEST-EAST MID LEVEL WARM-AIR ADVECTION OF AN ELEVATED MIXED LAYER WILL OCCUR TONIGHT...WITH 700MB TEMPS BY SUNRISE PROGGED TO RANGE FROM AROUND 10C IN THE EASTERN CWA TO AROUND 15C IN THE WEST. AT THE SURFACE...A NORTH-SOUTH TROUGH AXIS WILL ADVANCE EASTWARD INTO WESTERN NEB/FAR WESTERN KS TONIGHT...BUT OUT AHEAD OF THIS FEATURE THE CWA WILL CONTINUE TO EXPERIENCE STEADY SOUTH-SOUTHEAST BREEZES GENERALLY SUSTAINED 15+ MPH WITH SOME HIGHER GUSTS. THIS SHOULD HELP RESULT IN SLIGHTLY MILDER LOW TEMPS VERSUS LATELY...AND NUDGED PREVIOUS VALUES UP SLIGHTLY WITH MOST AREAS BOTTOMING OUT 65-69. STARTING TO SOUND LIKE A BROKEN RECORD...BUT WITH MODELS CONTINUING TO STRUGGLE MIGHTILY WITH CONVECTIVE TRENDS...CONFIDENCE IS BELOW AVERAGE. THE BOTTOM LINE IS THAT THERE IS ONLY A 20 PERCENT CHANCE OF SHOWERS/STORMS CWA-WIDE THROUGH 01Z/8PM...AND THEN AGAIN AFTER MIDNIGHT. THE PRE-8PM POTENTIAL WOULD STEM FROM ANY DIURNALLY- DRIVEN CONVECTION THAT WOULD MOST LIKELY FLIRT WITH FAR EASTERN COUNTIES...AND ANY HIGHER-BASED MID LEVEL CONVECTION THAT MIGHT SKIRT THE WEST. ALTHOUGH THE LIKELIHOOD OF VIGOROUS DEVELOPMENT IS QUITE LOW GIVEN LACK OF FORCING/LOW LEVEL FOCUS...CANNOT COMPLETELY RULE OUT A ROGUE STRONG/SEVERE STORM. BY SUNSET...HAVE DECENT CONFIDENCE IN A DRY PERIOD LOCALLY LASTING SEVERAL HOURS...BEFORE THE NEXT QUESTION BECOMES...DOES ANYTHING THAT DEVELOPS OUT WEST THIS EVENING SURVIVE EASTWARD INTO THE CWA...OR DOES NEW DEVELOPMENT OCCUR ON THE EDGE OF THE MID-LEVEL CAP AND WITHIN THE AXIS OF A FAIRLY STOUT 50+ KT LOW LEVEL JET. ALTHOUGH AM ONLY KEEPING POPS AT 20 PERCENT...IT WOULD SEEM THIS LATE NIGHT STORM POTENTIAL COULD BE A BIT MORE LIKELY/WIDESPREAD THAN LATE THIS AFTERNOON/EARLY EVENING...WITH MODELS SUCH AS THE RAP FIRING UP A DECENT AREA OF OVERNIGHT STORMS ESPECIALLY IN CENTRAL/EASTERN COUNTIES. SHOULD THESE STORMS ACTUALLY DEVELOP...CERTAINLY CAN/T DISCOUNT A THREAT FOR SEVERE HAIL WITH THE NAM DEPICTING 2000+ J/KG MUCAPE TO PARCELS BETWEEN 850-700MB. COULD BE AN INTERESTING FEW HOURS LATE TONIGHT IF IN FACT SOMETHING HAPPENS TO FIRE. TURNING TO THE THURSDAY DAYTIME PERIOD...OPTED TO HOLD THE COURSE FROM PREVIOUS FORECAST AND KEEP OUT ANY SHOWER/STORM MENTION FROM 12Z-00Z/7AM-7PM. ALOFT...AT LEAST SMALL MID LEVEL HEIGHT-RISES WILL CONTINUE AS THE RIDGE BUILDS INTO THE CENTRAL CONUS FROM THE SOUTHWEST...WHILE VERY WARM MID LEVEL 700MB TEMPS OF GENERALLY 13-15C OVERSPREAD THE ENTIRE CWA BY MID-AFTERNOON. AT THE SURFACE...THE AFOREMENTIONED TROUGH AXIS WILL STALL OUT FROM NORTH CENTRAL TO SOUTHWEST NEB DURING THE AFTERNOON...WHICH WILL ALLOW FOR RELAXING BREEZES ACROSS OUR FAR WESTERN COUNTIES...WHILE THE MAJORITY OF THE CWA CONTINUES TO EXPERIENCE SOUTHERLY SUSTAINED SPEEDS 15-20 MPH. WITH WARMER TEMPS MOVING IN ALOFT...DECENT MIXING...AND AT LEAST A FAIR AMOUNT OF SUNSHINE ESPECIALLY ONCE ANY POSSIBLE MORNING STRATUS BURNS OFF/LIFTS AWAY...WILL AIM FOR HIGHS RANGING FROM NEAR 90 NORTHEAST TO UPPER 90S SOUTHWEST...WHICH COMBINED WITH DEWPOINTS AVERAGING MID-UPPER 60S WILL YIELD HEAT INDEX VALUES GENERALLY 92-98 AT MID-AFTERNOON. THERE ARE TWO CAVEATS THAT COULD MESS UP THE DRY FORECAST. FIRST OFF...THERE IS A CHANCE THAT ANY LATE NIGHT/PRE-DAWN CONVECTION MAY NOT QUITE CLEAR OUR EASTERN COUNTIES BY 7AM IF IT FIRES UP...BUT GIVEN UNCERTAINTY IN DEVELOPMENT IN THE FIRST PLACE WILL DEFER TO NEXT SHIFT TO TAKE A CLOSER LOOK AT THE POSSIBILITY OF SOME MORNING POPS MAINLY WITHIN THE EASTERN 1/4 OF THE CWA. AGAIN...CAN/T RULE OUT SOME SEVERE-CRITERIA HAIL IF THIS UNFOLDS. ONCE THIS POTENTIAL MORNING CONVECTION VACATES...THE VAST MAJORITY OF THE DAY SHOULD BE STRONGLY CAPPED...AND THINK IT SHOULD HOLD THROUGH AT LEAST 7PM...DESPITE THE NAM ADVERTISING A VOLATILE LATE AFTERNOON ENVIRONMENT WITH 4000+ J/KG MLCAPE AND WEAK TO MODEST 25KT OF DEEP-LAYER SHEAR. REFLECTIVITY PROG FROM THE 12Z 4KM WRF- NMM CLEARLY KEEPS CONVECTION AT BAY LOCALLY...ALTHOUGH THE ECMWF DOES SUGGEST OUR FAR WESTERN COUNTIES COULD COME SOMEWHAT CLOSE TO ANYTHING THAT HAPPENS TO BREACH THE CAP ALONG THE TROUGH AXIS LYING NEAR THE CWA...BUT AGAIN THIS SEEMS AN UNLIKELY SCENARIO AND THUS THE LACK OF STORM MENTION AT THIS TIME. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 430 PM CDT WED JUN 19 2013 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND TEMPERATURES. MODELS ARE FAIRLY SIMILAR IN THE MAIN FEATURES THROUGH THE PERIOD. AN UPPER LEVEL LOW MOVES OUT OF THE NORTHERN ROCKIES AND INTO THE CANADIAN PLAINS THURSDAY NIGHT THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK...THEN AN UPPER LEVEL RIDGE BUILDS OVER THE AREA. FOR THURSDAY NIGHT THROUGH SATURDAY THERE IS A SURFACE WARM FRONT DRAPED THROUGH CENTRAL NEBRASKA. MODELS HAVE SOME SLIGHT DIFFERENCES IN THE LOCATION OF THE FRONT...BUT GENERALLY OVER THE FAR NORTHERN PART OF THE FORECAST AREA. AS AN UPPER LEVEL WAVE MOVES INTO THE AREA MODELS BRING IN SOME QPF ALONG THE FRONT THURSDAY NIGHT. THE CONCERN IS THAT THE 700MB TEMPERATURES ARE AT OR ABOVE 12 DEG C DURING THIS PERIOD. WITH THE FRONT IN THE AREA THERE IS SOME POTENTIAL THAT A THUNDERSTORM MIGHT BREAK THROUGH...BUT REALLY BELIEVE THAT WE WILL BE TOO CAPPED TO GET ANYTHING GOING. ON THE OFF CHANCE THAT THERE IS A THUNDERSTORM IT HAS THE POTENTIAL TO BE SEVERE. THE MUCAPE IN THE NORTH DURING THE EVENING IS AROUND 4500 J/KG. DURING THE DAYTIME BOTH FRIDAY AND SATURDAY HAVE MAINTAINED SOME SLIGHT CHANCE FOR THUNDERSTORMS IN THE SOUTHWEST. THIS WOULD BE MAINLY DURING THE AFTERNOON. EVEN THOUGH TEMPERATURES ARE EXPECTED TO BE QUITE WARM THAT AREA SEEMS PRONE TO SOME ISOLATED THUNDERSTORMS DURING THE HEAT OF THE DAY. SATURDAY NIGHT THROUGH SUNDAY NIGHT THE SURFACE LOW MOVES TOWARD THE EAST AND MAINLY STALLS ACROSS THE AREA BY SUNDAY AFTERNOON. WITH A COUPLE OF UPPER LEVEL WAVES THAT MOVE INTO THE AREA THERE COULD BE SOME THUNDERSTORMS ALONG THE FRONT. THE BEST CHANCES WOULD BE DURING THE NIGHT TIME HOURS. THE UPPER LEVEL PATTERN CHANGES LATE IN THE PERIOD AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE AREA. THE FEW UPPER LEVEL WAVES THAT MOVE ACROSS IT TEND TO BE FURTHER TO THE NORTH. EVEN IF THE SURFACE LOW IS TO THE WEST THERE ARE NOT MANY THUNDERSTORMS THAT TAKE OFF ON THE HIGH PLAINS. THEREFORE HAVE KEPT THE FORECAST DRY FOR MONDAY THROUGH WEDNESDAY. TEMPERATURES THROUGH THE PERIOD WILL REMAIN ON THE WARM SIDE. EARLY IN THE PERIOD THE WARM FRONT IS THROUGH THE AREA AND EVEN THE SURFACE LOW AS IT MOVES TO THE EAST DOES NOT BRING MUCH IN THE WAY OF COOLER TEMPERATURES. TEMPERATURES ARE EXPECTED TO BE QUITE A BIT ABOVE NORMAL. && .AVIATION...(FOR THE 18Z KGRI TAF THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 117 PM CDT WED JUN 19 2013 AT LEAST FOR NOW...VFR CEILING/VISIBILITY IS FORECAST TO PREVAIL THROUGH THE PERIOD...BUT THERE ARE A FEW QUESTION MARKS. STARTING WITH THIS AFTERNOON/EVENING...CONFIDENCE IS HIGH IN VFR CONDITIONS WITH ONLY THE SLIGHTEST CHANCE OF A SHOWER/THUNDERSTORM NOT WORTH MENTIONING. LATE TONIGHT INTO THURSDAY MORNING...THERE ARE SIGNS THAT AN MVFR STRATUS DECK COULD OVERTAKE THE AREA...BUT GIVEN HOW POORLY MODELS HAVE HANDLED OTHER WEATHER ELEMENTS LATELY...AM NOT QUITE READY TO JUMP ON BOARD SO FOR NO HAVE ONLY INDICATED SCATTERED LOW CLOUDS...AND WILL DEFER TO LATER FORECASTS TO BEEF UP THE POTENTIAL OR NOT. THERE COULD ALSO BE A LATE-NIGHT THUNDERSTORM...BUT AGAIN CHANCES SEEM TO LOW TO MENTION. WIND-WISE...SURFACE WINDS WILL AVERAGE FAIRLY BREEZY THROUGHOUT THE PERIOD...WITH DAYTIME SUSTAINED SPEEDS AROUND 16-17KT AND GUST POTENTIAL TO AROUND 25KT...AND EVEN OVERNIGHT GUSTS TO AROUND 20KT. HAVE INTRODUCED A MENTION OF LOW LEVEL WIND SHEAR WITH THIS FORECAST BETWEEN 06Z-15Z...AS A STRONG LOW LEVEL JET DEVELOPS OVERHEAD. WIND SPEEDS BETWEEN 1500 AND 2000 FT AGL ARE FORECAST TO TO RAMP UP BETWEEN 40-46KT FROM THE SOUTH...CREATING AT LEAST 30-35 KNOTS OF BULK SHEAR MAGNITUDE BETWEEN THE SURFACE AND THIS LEVEL CONSIDERING SUSTAINED SURFACE SPEEDS ONLY AROUND 14KT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...PFANNKUCH LONG TERM...JCB AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1250 PM CDT WED JUN 19 2013 .AVIATION... 18Z TAFS FOR KOMA...KLNK...KOFK. THESE TYPICAL MID JUNE PATTERNS GENERALLY CONSIST OF VFR CONDITIONS MOST OF THE TIME EXCEPT FOR DURING PERIODS OF THUNDERSTORMS. UNFORTUNATELY THE CONFIDENCE IN PICKING OUT WHEN AND WHERE STORMS WILL DEVELOP IS RATHER LOW...AND THIS PATTERN IS NO EXCEPTION. THERE ARE SOME WEAK SIGNALS THAT POINT TO NORTHEAST NEBRASKA DURING THE LATE AFTERNOON AND EVENING TIME FRAME...WHICH WOULD HAVE A GREATER IMPACT ON THE KOFK TAF. HOWEVER GIVEN THE HIGH UNCERTAINTY... HAVE LEFT TRW OUT OF THE TAFS AT THIS TIME AND WILL CLOSELY BE MONITORING RADAR FOR TRENDS. NIETFELD && .PREV DISCUSSION... /ISSUED 337 AM CDT WED JUN 19 2013/ DISCUSSION... ALTHOUGH WE ARE NOT EXPECTING A CONTINUOUS PERIOD OF SHOWERS AND THUNDERSTORMS OVER THE NEXT 48 HOURS...IT REALLY IS DIFFICULT TO DISCERN ANY PERIOD IN THAT TIME THAT SHOULD NOT WARRANT AT LEAST A SLIGHT CHANCE POP. THEREFORE...WE WILL BE CARRYING A SMALL POP FOR PORTIONS OF THE CWA THROUGH THIS TIME WITH GREAT UNCERTAINTY ON TIMING/LOCATION. MODEL GUIDANCE HAS PERFORMED RATHER POORLY ON WEAK CONVECTIVE EVENTS IN THE PAST COUPLE DAYS AND SO FORECASTER CONFIDENCE REMAINS LOW. UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY SHOW A LARGE TROUGH OFF THE PACIFIC COAST WITH THE LOW PRESSURE CENTERED JUST OFF THE OREGON/WASHINGTON COASTS. OUT AHEAD OF THIS IS A WEAK RIDGE OF HIGH PRESSURE EXTENDING FROM THE SOUTHERN PLAINS INTO THE WESTERN DAKOTAS. SEVERAL WEAK IMPULSES ARE EMBEDDED WITHIN THE SOUTHWEST FLOW IN BETWEEN THE MAIN FEATURES. THE FIRST SHORTWAVE OF CONCERN IS CURRENTLY LOCATED OVER THE NEBRASKA PANHANDLE. LATEST REGIONAL RADAR MOSIAC SHOWS A CONVECTIVE COMPLEX SLOWLY DRIFTING EAST AND WEAKENING ACROSS WESTERN NEBRASKA WHILE ANOTHER MOVES SLOWLY NORTHEAST ACROSS NORTHWEST KANSAS AND WEAKENS. LATEST RAP BRINGS A HINT OF THIS ACTIVITY INTO THE FORECAST AREA THROUGHOUT THE MORNING AND AM GOING TO TWEEK POPS ACCORDINGLY. BROAD SCALE LIFT ASSOCIATED WITH THE MID LEVEL IMPULSE WILL STILL BE PRESENT INTO THE AFTERNOON AND AS INSTABILITY INCREASES WITH DAYTIME HEATING...FEEL THUNDERSTORMS HAVE A CHANCE TO CONTINUE ACROSS THE FORECAST AREA IN A BROAD LOW LEVEL WARM AIR ADVECTION REGIME. LOW LEVEL JET WILL VEER SLIGHTLY OVERNIGHT AND COULD SUSTAIN CONVECTIVE ACTIVITY...THEREFORE WILL CONTINUE A POP THROUGH THE OVERNIGHT. BY THURSDAY...THE UPPER RIDGE AXIS WILL BE DIRECTLY OVERHEAD AND EXTEND INTO THE EASTERN DAKOTAS. IN ADDITION...A SFC COLD FRONT WILL EXTEND SOUTH ACROSS THE CENTRAL DAKOTAS AND INTO NORTHWEST NEBRASKA WHICH WILL LIKELY BE THE FOCUS FOR THUNDERSTORM DEVELOPMENT. VERY STRONG INSTABILITY WILL EXIST IN OUR NORTHERN CWA HOWEVER A QUITE STOUT CAP WILL ALSO BE IN PLACE WHICH MAY PROHIBIT THE EASTWARD EXPANSION OF TSTMS. SPC HAS INCLUDED OUR NORTH IN THE SWODY2 FOR ANY MCS ACTIVITY MOVING SOUTHEAST FROM NRN PLAINS CONVECTION. THIS WILL BE AIDED BY A VEERING SOUTHWEST LOW LEVEL JET AND SO HAVE HIGHER POPS GOING IN OUR NORTH. THE AREA IS DOMINATED BY SOUTHWEST FLOW ALOFT INTO THE WEEKEND WITH THE MAIN UPPER LOW MOVING ACROSS THE PACIFIC NORTHWEST AND TOWARD THE NORTHERN PLAINS. THE MAIN SFC BOUNDARY WILL REMAIN TO OUR NORTH LEAVING THE REGION IN THE WARM SECTOR. HIGHS WILL LIKELY TOP OUT IN THE LOW 90S. AS THE UPPER LOW MOVES TOWARD THE NORTHERN PLAINS BY SUNDAY...THE SFC FRONT WILL DROP SOUTH INTO THE AREA AND BE THE POTENTIAL FOCUS FOR THUNDERSTORMS. KERN && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
119 PM MDT WED JUN 19 2013 .UPDATE... SHARPENING DRYLINE OCCURRING OVER THE EASTERN PLAINS AS LOW LEVEL MOIST EASTERLY FLOW IS MUCH STRONGER THAN MODEL GUIDANCE SHOWED FROM YESTERDAY. THIS WILL LEAD TO SOME STRONG TO LOCALLY SEVERE CONVECTION OVER THE FAR EASTERN COUNTIES WHERE SPC SLIGHT RISK HAS EXPANDED TO LINE UP WITH DEVELOPING CONVECTION AND VERY STRONG INSTABILITY. ALL THAT NEEDS TO HAPPEN NOW IS LIFT WHICH IS SHOWN BY THE 16Z HRRR TO OCCUR BETWEEN 20Z AND 21Z. UPDATED TO RAISE POPS AND INCLUDE SEVERE WORDING ALONG THE TX STATE LINE. GUYER && .PREV DISCUSSION...1141 AM MDT WED JUN 19 2013... .AVIATION... 18Z TAF CYCLE MAIN AVIATION THREATS TODAY WILL BE FOUND ALONG THE DRYLINE WHICH IS EXPECTED TO BE FOUND ACROSS THE EASTERN PLAINS. STORMS SHOULD FIRE UP ALONG THIS BOUNDARY AND THEN MOVE TOWARDS THE NORTHEAST. ROW AND TCC HAVE THE BEST CHANCE OF STORM IMPACTS. WIND IS A BIG THREAT AND HAVE INCLUDED BLOWING DUST AT ROW. CANT RULE OUT A DRIER SHOWER AND WIND IMPACTING LVS BUT MORE POTENTIAL SOUTH AND EAST. TURBULENT MIXING AND MODERATE TO STRONG WINDS WILL BE FOUND ELSEWHERE THROUGH EARLY EVENING. SIMILAR SCENARIO FOR THURSDAY ALTHOUGH THERE IS SOME POTENTIAL FOR THE DRYLINE TO BE SHUNTED A LITTLE FURTHER WEST BUT NOT BY MUCH. 50 .PREV DISCUSSION...318 AM MDT WED JUN 19 2013... THE LATEST WATER VAPOR SATELLITE IMAGERY SHOWS THE PACIFIC DRY SLOT OVER SOCAL...AZ AND NW MEXICO POISED TO PUNCH INTO OUR AREA TODAY AS AN UPPER LEVEL LOW/TROUGH TRANSITIONS FURTHER INLAND ACROSS THE PACIFIC NW. VERY DRY AIR IS ALREADY PUSHING INTO WESTERN PORTIONS OF THE AREA WHERE DEWPOINT 24HR CHANGE VALUES ARE AN AVERAGE -10...WITH THE LATEST OBSERVED VALUES IN THE SINGLE DIGITS AND LOW TEENS. THIS VERY DRY AIRMASS IS CONTRASTED WITH DEWPOINT TEMPS IN THE 50S TO NEAR 60 EAST OF THE CENTRAL MOUNTAIN CHAIN WHERE GULF MOISTURE WILL LINGER FOR MUCH OF THE DAY AND ACT AS FUEL FOR SHOWERS AND THUNDERSTORMS BY AFTERNOON. THE DRY SLOT IS FORECAST TO PUSH EAST TODAY...WITH LOW LAYER MOISTURE ACROSS CENTRAL AREAS MIXING-OUT QUICKLY AND A DRY LINE SHARPENING UP ACROSS THE HIGHLANDS AND EASTERN PLAINS. AFTERNOON AND EVENING CONVECTION IS ANTICIPATED...ALTHOUGH ISOLATED...ALONG AND EAST OF THE DRY LINE. 00Z NAM12 FORECAST SBCAPE OF 3000-3500 J/KG WITH 0-6KM BULK SHEAR OF 35-45KTS...INDICATING AN ATMOSPHERE CAPABLE OF SUPPORTING SUPERCELLS. CRITICAL FIRE WEATHER CONDITIONS ARE FORECAST WEST OF THE DRYLINE...PUSHING INTO THE EASTERN PLAINS LATE IN THE DAY (SEE DETAILS IN FIRE WX DISCUSSION BELOW). BREEZY TO LOCALLY WINDY CONDITIONS ARE EXPECTED AREAWIDE THIS AFTERNOON AND EVENING...ESPECIALLY WEST OF THE DRY LINE WITH DEEP LAYER MIXING FORECAST. SOME BLOWING DUST IS POSSIBLE BY LATE AFTERNOON ...BUT HARD TO SAY WHERE WITH WIND SPEEDS PERHAPS JUST SHY OF LOWER THRESHOLDS. THE NORTHWEST PLATEAU AND THE ABQ WEST MESA LOOK TO HAVE THE BEST SHOT...BUT VISIBILITIES LIKELY TO STAY AT 6 MILES OR HIGHER. MORE CRITICAL FIRE WEATHER CONDITIONS POSSIBLE THURSDAY FOR MUCH OF THE NORTH AND WEST AS THE DRY SLOT PERSISTS OVER THE AREA. CHANCES FOR SHOWERS AND THUNDERSTORMS ON THURSDAY WILL BE CONFINED TO THE SOUTH CENTRAL MOUNTAINS AND THE SOUTHEAST PLAINS WHERE MOISTURE WILL LINGER...BUT MID LEVEL WARMING WILL LIMIT THE AVAILABLE POTENTIAL ENERGY AND WETTING RAINS WILL BE HARDER TO COME-BY. SW FLOW ALOFT TO PERSIST THROUGH THE WEEKEND AS THE PACIFIC UPPER LOW MAKES SLOW EASTWARD PROGRESS ACROSS THE NORTHERN ROCKIES AND THE UPPER HIGH BECOMES ESTABLISHED OVER WEST TEXAS. THE GFS CONTINUES TO SHOW MOISTURE ROUNDING THE PERIPHERY OF THE UPPER HIGH AND LAYING-OVER MUCH OF SOUTHERN AND EASTERN NEW MEXICO WITH DRY AIR PERSISTING ACROSS MUCH OF THE NORTH. POPS HAVE BEEN CONFINED MORE TO THE EAST AND SOUTH WITH THE LATEST MODEL RUNS NOT SO ENCOURAGING FOR PRECIP HERE IN THE ABQ METRO. THE MODELS CONTINUE TO SHOW THE UPPER HIGH DRIFTING NORTH ACROSS NM AND BECOMING ANCHORED OVER COLORADO BY THE MIDDLE OF NEXT WEEK WITH DEEP EASTERLY FLOW PREVAILING ACROSS NM. HOWEVER...THE DOMINANT UPPER HIGH LOOKS TO KEEP TROPICAL MOISTURE WELL SOUTH OF THE FORECAST AREA. NO BIG CHANGES TO FORECAST TEMPS THIS CYCLE WITH ABOVE NORMAL HIGHS AND LOWS PERSISTING THROUGH THE NEXT 7 DAYS. 11 .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS MOST AREAS EXCEPT EXTREME EASTERN PLAINS TODAY AND THURSDAY. CRITICAL CONDITIONS TO CONTINUE WESTERN HIGH TERRAIN AND NORTHEAST HIGHLANDS THROUGH THE WEEKEND... FEW CHANGES MADE TO FORECAST PACKAGE IN THE SHORT TERM. POTENT UPPER LEVEL LOW MOVING NEARING THE PACIFIC NORTHWEST COAST WITH RELATIVELY STRONG JET AND DRY SLOT AT THE BASE OF THE TROUGH. SECOND JET MAX AND BROADER AREA OF DRY AIR STRETCHED ACROSS ARIZONA AND INTO NW NEW MEXICO. CIRA LAYERED PW PRODUCT DEPICTS VERY DRY AIR AT BOTH 850 TO 700MB AND 700 TO 500 MB LAYERS. AS THE PACIFIC TROUGH APPROACHES... THE UPPER RIDGE HAS MOVED TO THE EAST AND WEAKEN A BIT. MODELS INDICATE DEEPER MIXING TODAY AND SOUTHWEST WINDS WILL STRENGTHEN STEADILY...ESPECIALLY OVER HIGHER TERRAIN. THUS...CRITICAL FIRE WEATHER CONDITIONS EXPECTED TO DEVELOP BY MID DAY AND EXPAND IN COVERAGE THROUGH THE AFTERNOON. SUPER HAINES PROBABLE ACROSS WESTERN ZONES. WITH PERSISTENT MOIST SOUTH TO SOUTHEAST FLOW INTO THE EASTERN PLAINS...MINIMUM RH VALUES ARE EXPECTED TO REMAIN ABOVE 15 PERCENT WITH ISOLATED THUNDERSTORMS. SOME OF THESE STORMS COULD BE OF THE DRY VARIETY GENERALLY ALONG THE NORTHEAST AND CENTRAL HIGHLANDS. OVERNIGHT RH RECOVERIES TO BE POOR WESTERN AND CENTRAL ZONES. SIMILAR SITUATION ON THURSDAY AS HEIGHTS CONTINUE TO DECREASE AND THE GRADIENT STRENGTHENS A BIT OVER THE STATE. UPPER LEVEL HIGH CENTERED OVER WEST TEXAS WITH MOIST SOUTHERLY LOW LEVEL FLOW EXTREME EAST. WILL LEAVE FIRE WEATHER WATCH IN PLACE...BUT DECREASED DEWPOINTS ALL LOCATIONS...INCLUDING THE EAST SUCH THAT THE WESTERN PORTIONS OF ZONES 104 AND 108 LOOK TO REACH CRITICAL CRITERIA AND MAY NEED TO BE ADDED. SUPER HAINES ONCE AGAIN ACROSS WESTERN ZONES AND NORTH CENTRAL ZONES AS WELL. UPPER HIGH TO REMAIN OVER WEST TEXAS FRIDAY THROUGH SUNDAY. PREVIOUSLY...EXTENDED MODELS DEPICTED A NORTHWARD FLUX OF MOISTURE OVER THE STATE SUPPORTING SLIGHT CHANCES OF WETTING RAIN CENTRAL AND EASTERN ZONES. HOWEVER...LATEST GFS IS DRIER WITH CONTINUED SOUTHWEST FLOW AND MOIST RETURN FLOW LIMITED TO THE SOUTHEAST AND EXTREME EAST CENTRAL PLAINS. THUS DEWPOINTS AND POPS WERE TRIMMED BACK ACROSS THE NORTHWEST AND CENTRAL ZONES WITH SLIGHT CHANCES FOR WETTING RAIN REMAINING SOUTH AND SOUTHEAST ZONES. LIMITED AREAS OF CRITICAL FIRE WEATHER CONDITIONS...MAINLY WESTERN HIGH TERRAIN AND NORTHEAST HIGHLANDS... WITH SUPER HAINES WEST AND NORTH ARE POSSIBLE EACH DAY. EXTENDED MODELS BUILD THE UPPER HIGH OVER NEW MEXICO BY MID WEEK... WITH VERY DRY CONDITIONS PERSISTING BUT LIGHTER WINDS. 05 && .ABQ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR THE FOLLOWING ZONES...NMZ101>109. FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR THE FOLLOWING ZONES...NMZ101>103-105>107-109. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
146 PM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE CRUISES WEDNESDAY AND THURSDAY...BEFORE DROPPING ANCHOR IN THE WESTERN ATLANTIC TO BEGIN THE SUMMER SEASON. HIGH RIDGE ALOFT KEEPS DRY CONDITIONS THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 1145 AM UPDATE...STRATUS ERODING RAPIDLY SO THAT MOST OF THIS AFTERNOON WILL SEE LOTS OF SUNSHINE AND WARM TEMPERATURES. STILL WILL LEAVE A SLIGHT CHANCE IN THE MOUNTAINS BEFORE DRY AIR MIXES DOWN LATER AROUND MID AFTERNOON. WILL INCLUDE LOCALLY DENSE FOG TONIGHT. 630 AM UPDATE... SFC FRONT ROUGHLY FROM POCAHONTAS COUNTY SW-WARD TO JUST NORTH OF BKW AT THIS TIME AND WILL CONTINUE A BIT FURTHER SOUTHWARD INTO VIRGINIA BEFORE STALLING LATER THIS MORNING. TWEAKED SKY COVER TO REFLECT QUICKER CLEARING ACROSS SE OHIO AND INTO ADJACENT WEST VIRGINIA. INGESTED RECENT OBS. OTHERWISE...NO MAJOR CHANGES. PREVIOUS DISCUSSION... AT 06Z SFC OBS INDICATE SECONDARY FRONT LOCATED ROUGHLY FROM HTS EAST/NORTHEAST TO NEAR CKB. NEAR AND AHEAD OF IT A FEW SHOWERS AND EVEN ONE THUNDERSTORM HAD REDEVELOPED EARLY THIS MORNING. THE ENHANCEMENT LIKELY DUE TO A VORT MAX...EVIDENT IN WV IMAGERY...MOVING QUICKLY ACROSS NORTH CENTRAL OHIO. ALL IN ALL EXPECT A NICE DAY FOR MOST FOLKS AS THE AFOREMENTIONED FRONT MOVES THROUGH THE AREA...UNDER PARTLY TO MOSTLY SUNNY SKIES BY THE AFTERNOON AND SEASONABLY WARM TEMPS. LARGE SCALE FORCING FOR SUBSIDENCE WILL OVERSPREAD THE FORECAST AREA FROM NW TO SE AS A 500MB S/W TROUGH PUSHES EASTWARD ACROSS AND EXITS TO THE EAST AROUND THE 18Z-21Z TIME FRAME. BY THE AFTERNOON HOURS HOWEVER...THE SFC FRONT BEGINS TO WASH OUT AND AS SFC HIGH PRESSURE REBUILDS TO THE EAST. MODELS IN GOOD AGREEMENT WITH GOOD SFC CONVERGENCE ALONG THE EASTERN HIGH TERRAIN PEAKS AS SFC FLOW ON THE EAST SIDE RETURNS QUICKLY TO THE EAST/SOUTHEAST...WHILE FLOW ON THE WINDWARD SIDE REMAINS NORTH/NORTHWEST. SOME QUESTION AND DOUBT AS TO THE DEPTH OF MOISTURE BEING DEPICTED ON LATEST NAM12 SOUNDINGS HOWEVER...AND LATEST RUC13 SOUNDINGS ARE INDEED MUCH DRYER IN LOWER LEVELS. EVEN WITH THE MORE SATURATED NAM12...PWATS STILL ONLY PROGGED AROUND 0.8IN-0.9IN WITH VERY DRY AIR ALOFT WHICH WOULD SERVE TO LIMIT COVERAGE. PREV FCST HAD A GOOD HANDLE ON THIS AND WILL CONTINUE SLIGHT CHANCE TO LOW CHANCE POPS ESSENTIALLY FROM THE HIGHEST PEAKS AND POINTS SOUTH AND EAST...WITH STORM MOTION TO THE SOUTHEAST. DID INSERT A SLIGHT THUNDER MENTION WITH DECENT INSTABILITY IN THAT AREA. AS SUCH...KEPT CLOUD COVER HIGHER IN THE EASTERN HIGH COUNTRY AS WELL. ALSO NUDGED MAX TEMPS UP AN ADDITIONAL DEGREE OR TWO FOR MOST LOCATIONS PER LATEST PROGGED 925MB AND 850MB TEMPS WITH MOS GUIDANCE SUPPORTING...ALTHOUGH DID KEEP MAX TEMPS IN THE MOUNTAINS JUST A BIT LOWER WITH MORE CLOUDS AND SOME AFTERNOON PRECIP POTENTIAL. OVERNIGHT FORECAST REMAINS VIRTUALLY UNCHANGED FROM PREV SHIFT THINKING...WITH MINS IN THE MID AND UPPER 50S LOWLANDS. WILL HAVE PRECIP ENDING AT 00Z THU IN THE MOUNTAINS. AREAS OF FOG ARE A GOOD BET ONCE AGAIN IN THE LOWLANDS UNDER A MOSTLY CLEAR SKY AND NEAR-CALM WINDS...ALTHOUGH SOME LOWER DEWPOINTS ACROSS SE OHIO AND MORE CLOUD COVER IN THE MOUNTAINS MAY LIMIT COVERAGE IN THOSE AREAS. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... SFC HIGH PRESSURE MOVE OFF SHORE THE NORTHEAST COAST LATE THURSDAY LOSING ITS INFLUENCE WEST OF THE APPALACHIANS. HOWEVER...ABUNDANT LOW LEVEL MOISTURE AND ELEVATED HEAT SOURCES COULD PRODUCE ISOLATED AFTERNOON SHOWERS OR STORMS OVER HIGHER ELEVATIONS THROUGH THE WEEKEND. A MID LEVEL RIDGE MOVES OVERHEAD SATURDAY PROVIDING SOME SUBSIDENCE AND CLEAR SKIES. AFTERNOON CU WILL BE COMMON JUST TO DISSIPATE AFTER SUNSET. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... SURFACE HIGH PRESSURE WILL REMAIN CENTERED ACROSS THE SOUTHEAST STATES...WITH A RIDGE EXTENDING NORTH INTO WEST VIRGINIA. SOUTHERLY WINDS WILL RESULT IN DEW POINTS INCREASING TO THE UPPER 60S AND LOWER 70S. AS A RESULT...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM WILL BE A POSSIBILITY...MAINLY DURING THE AFTERNOON AND EVENING HOURS. AN UPPER LEVEL TROF AND AN ASSOCIATED COLD FRONT WILL APPROACH FROM THE WEST LATE IN THE PERIOD...RESULTING IN BETTER CHANCES FOR SHOWERS AND STORMS. THE BEST CHANCE OF GETTING WET WILL CONTINUE TO BE DURING THE AFTERNOON AND EVENING HOURS. EXPECT DAYTIME TEMPERATURES TO GENERALLY BE 5 OR MORE DEGREES ABOVE NORMAL DURING THE PERIOD. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... 18Z WEDNESDAY THROUGH 18Z THURSDAY... HIGH PRESSURE DOMINATES. STUBBORN STRATUS OVER CENTRAL WEST VIRGINIA FINALLY ERODES BY 19Z...SO THAT GENERAL VFR SCT-BKN CU WILL PREVAIL THROUGH 00Z. AFTER 00Z VFR MOSTLY CLEAR EXCEPT FOR LOCALLY DENSE RIVER AND VALLEY FOG 06Z TO 12Z AFFECTING THE MAJOR TERMINALS. AFTER 14Z...VFR SCT-BKN CU. JUST A SMALL CHANCE OF AN AFTERNOON THUNDERSTORM...MAINLY OVER THE MOUNTAIN HIGH TERRAIN. CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE...MEDIUM TO HIGH. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY... FORECAST CONFIDENCE: TIMING OF DENSITY OF REDUCED VIS AND/OR LOW STRATUS AFTER 06Z THU MAY VARY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H M M H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z THURSDAY... IFR OR WORSE FG DEVELOPING WED NT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/50 NEAR TERM...JMV SHORT TERM...ARJ LONG TERM...JSH AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1146 AM EDT WED JUN 19 2013 .SYNOPSIS... HIGH PRESSURE CRUISES WEDNESDAY AND THURSDAY...BEFORE DROPPING ANCHOR IN THE WESTERN ATLANTIC TO BEGIN THE SUMMER SEASON. HIGH RIDGE ALOFT KEEPS DRY CONDITIONS THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 1145 AM UPDATE...STRATUS ERODING RAPIDLY SO THAT MOST OF THIS AFTERNOON WILL SEE LOTS OF SUNSHINE AND WARM TEMPERATURES. STILL WILL LEAVE A SLIGHT CHANCE IN THE MOUNTAINS BEFORE DRY AIR MIXES DOWN LATER AROUND MID AFTERNOON. WILL INCLUDE LOCALLY DENSE FOG TONIGHT. 630 AM UPDATE... SFC FRONT ROUGHLY FROM POCAHONTAS COUNTY SW-WARD TO JUST NORTH OF BKW AT THIS TIME AND WILL CONTINUE A BIT FURTHER SOUTHWARD INTO VIRGINIA BEFORE STALLING LATER THIS MORNING. TWEAKED SKY COVER TO REFLECT QUICKER CLEARING ACROSS SE OHIO AND INTO ADJACENT WEST VIRGINIA. INGESTED RECENT OBS. OTHERWISE...NO MAJOR CHANGES. PREVIOUS DISCUSSION... AT 06Z SFC OBS INDICATE SECONDARY FRONT LOCATED ROUGHLY FROM HTS EAST/NORTHEAST TO NEAR CKB. NEAR AND AHEAD OF IT A FEW SHOWERS AND EVEN ONE THUNDERSTORM HAD REDEVELOPED EARLY THIS MORNING. THE ENHANCEMENT LIKELY DUE TO A VORT MAX...EVIDENT IN WV IMAGERY...MOVING QUICKLY ACROSS NORTH CENTRAL OHIO. ALL IN ALL EXPECT A NICE DAY FOR MOST FOLKS AS THE AFOREMENTIONED FRONT MOVES THROUGH THE AREA...UNDER PARTLY TO MOSTLY SUNNY SKIES BY THE AFTERNOON AND SEASONABLY WARM TEMPS. LARGE SCALE FORCING FOR SUBSIDENCE WILL OVERSPREAD THE FORECAST AREA FROM NW TO SE AS A 500MB S/W TROUGH PUSHES EASTWARD ACROSS AND EXITS TO THE EAST AROUND THE 18Z-21Z TIME FRAME. BY THE AFTERNOON HOURS HOWEVER...THE SFC FRONT BEGINS TO WASH OUT AND AS SFC HIGH PRESSURE REBUILDS TO THE EAST. MODELS IN GOOD AGREEMENT WITH GOOD SFC CONVERGENCE ALONG THE EASTERN HIGH TERRAIN PEAKS AS SFC FLOW ON THE EAST SIDE RETURNS QUICKLY TO THE EAST/SOUTHEAST...WHILE FLOW ON THE WINDWARD SIDE REMAINS NORTH/NORTHWEST. SOME QUESTION AND DOUBT AS TO THE DEPTH OF MOISTURE BEING DEPICTED ON LATEST NAM12 SOUNDINGS HOWEVER...AND LATEST RUC13 SOUNDINGS ARE INDEED MUCH DRYER IN LOWER LEVELS. EVEN WITH THE MORE SATURATED NAM12...PWATS STILL ONLY PROGGED AROUND 0.8IN-0.9IN WITH VERY DRY AIR ALOFT WHICH WOULD SERVE TO LIMIT COVERAGE. PREV FCST HAD A GOOD HANDLE ON THIS AND WILL CONTINUE SLIGHT CHANCE TO LOW CHANCE POPS ESSENTIALLY FROM THE HIGHEST PEAKS AND POINTS SOUTH AND EAST...WITH STORM MOTION TO THE SOUTHEAST. DID INSERT A SLIGHT THUNDER MENTION WITH DECENT INSTABILITY IN THAT AREA. AS SUCH...KEPT CLOUD COVER HIGHER IN THE EASTERN HIGH COUNTRY AS WELL. ALSO NUDGED MAX TEMPS UP AN ADDITIONAL DEGREE OR TWO FOR MOST LOCATIONS PER LATEST PROGGED 925MB AND 850MB TEMPS WITH MOS GUIDANCE SUPPORTING...ALTHOUGH DID KEEP MAX TEMPS IN THE MOUNTAINS JUST A BIT LOWER WITH MORE CLOUDS AND SOME AFTERNOON PRECIP POTENTIAL. OVERNIGHT FORECAST REMAINS VIRTUALLY UNCHANGED FROM PREV SHIFT THINKING...WITH MINS IN THE MID AND UPPER 50S LOWLANDS. WILL HAVE PRECIP ENDING AT 00Z THU IN THE MOUNTAINS. AREAS OF FOG ARE A GOOD BET ONCE AGAIN IN THE LOWLANDS UNDER A MOSTLY CLEAR SKY AND NEAR-CALM WINDS...ALTHOUGH SOME LOWER DEWPOINTS ACROSS SE OHIO AND MORE CLOUD COVER IN THE MOUNTAINS MAY LIMIT COVERAGE IN THOSE AREAS. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... SFC HIGH PRESSURE MOVE OFF SHORE THE NORTHEAST COAST LATE THURSDAY LOSING ITS INFLUENCE WEST OF THE APPALACHIANS. HOWEVER...ABUNDANT LOW LEVEL MOISTURE AND ELEVATED HEAT SOURCES COULD PRODUCE ISOLATED AFTERNOON SHOWERS OR STORMS OVER HIGHER ELEVATIONS THROUGH THE WEEKEND. A MID LEVEL RIDGE MOVES OVERHEAD SATURDAY PROVIDING SOME SUBSIDENCE AND CLEAR SKIES. AFTERNOON CU WILL BE COMMON JUST TO DISSIPATE AFTER SUNSET. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... SURFACE HIGH PRESSURE WILL REMAIN CENTERED ACROSS THE SOUTHEAST STATES...WITH A RIDGE EXTENDING NORTH INTO WEST VIRGINIA. SOUTHERLY WINDS WILL RESULT IN DEW POINTS INCREASING TO THE UPPER 60S AND LOWER 70S. AS A RESULT...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM WILL BE A POSSIBILITY...MAINLY DURING THE AFTERNOON AND EVENING HOURS. AN UPPER LEVEL TROF AND AN ASSOCIATED COLD FRONT WILL APPROACH FROM THE WEST LATE IN THE PERIOD...RESULTING IN BETTER CHANCES FOR SHOWERS AND STORMS. THE BEST CHANCE OF GETTING WET WILL CONTINUE TO BE DURING THE AFTERNOON AND EVENING HOURS. EXPECT DAYTIME TEMPERATURES TO GENERALLY BE 5 OR MORE DEGREES ABOVE NORMAL DURING THE PERIOD. && .AVIATION /16Z WEDNESDAY THROUGH SUNDAY/... 16Z WEDNESDAY THROUGH 12Z THURSDAY... STRATUS ERODING QUICKLY SO THAT GENERAL VFR SCT-BKN CU WILL PREVAIL AFTER 18Z. JUST A FEW SHOWERS AND PERHAPS A THUNDERSTORM ARE POSSIBLE OVER THE EASTERN HIGH TERRAIN. WILL ADD LOCALLY DENSE RIVER AND VALLEY FOG AFTER 06Z TONIGHT...AFFECTING MOST MAJOR TERMINALS. CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE...MEDIUM. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY... FORECAST CONFIDENCE: TIMING OF DENSITY OF REDUCED VIS AND/OR LOW STRATUS AFTER 06Z THU MAY VARY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21 CRW CONSISTENCY H M H H H H H H H H H H HTS CONSISTENCY M H H H H H H H H H H H BKW CONSISTENCY M M M H H H H H H H H H EKN CONSISTENCY H M M H H H H H H H H H PKB CONSISTENCY M H H H H H H H H H H H CKB CONSISTENCY H M H H H H H H H H H H AFTER 18Z THURSDAY... IFR OR WORSE FG DEVELOPING WED NT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/50 NEAR TERM...JMV SHORT TERM...ARJ LONG TERM...JSH AVIATION...JMV
AREA FORECAST DISCUSSION
NWS NORMAN OK
104 PM CDT WED JUN 19 2013 .DISCUSSION... 18Z AVIATION DISCUSSION FOLLOWS.... && .AVIATION... A THUNDERSTORM COMPLEX SW OF KHBR-KLAW-KSPS WILL CONTINUE TO MOVE SSE THIS AFTERNOON. NO TSRA ARE LIKELY AT OUR TAF SITES...BUT STRONG TO SEVERE TSRA MAY OCCUR FARTHER SW EARLY THIS AFTERNOON. A WAKE LOW HAS GENERATED A VERY TIGHT PRESSURE GRADIENT ACROSS SW OK...SO SMALL AREAS OF RATHER STRONG WINDS WILL SHIFT SLOWLY SSE...ALONGSIDE THE COMPLEX. SCT TSRA MAY FORM LATER TODAY/TONIGHT OVER W OR N OK...BASED ON MODEL FORECASTS...HOWEVER THE TSRA COMPLEX MAY HAVE ALTERED THE ATMOSPHERE SUFFICIENTLY TO PREVENT THIS DEVELOPMENT. SOME GULF STRATUS IS POSSIBLE OVER THE E 1/2 OF OK TOMORROW MORNING...BUT CONFIDENCE IS NOT HIGH ENOUGH AT THIS TIME TO INCLUDE MVFR CONDITIONS. && .PREV DISCUSSION... /ISSUED 1140 AM CDT WED JUN 19 2013/ UPDATE... MADE A FEW MINOR TWEAKS TO THE GOING FORECAST. SOUTHERN END OF ONGOING STORM COMPLEX HAS MOVED INTO FAR WESTERN NORTH TEXAS. HAVE UPPED POPS TO LIKELY OVER THIS AREA AND MAINTAIN CHANCE POPS THROUGH LATE AFTERNOON. THEREAFTER...ONLY ISOLATED ACTIVITY IS EXPECTED BEFORE ADDITIONAL STORMS DEVELOP THIS EVENING AND OVERNIGHT. GIVEN SUBSTANTIAL CLOUD COVER HAS LIMITED HEATING ACROSS SOUTHWEST OKLAHOMA AND NORTH TEXAS...HAVE TWEAKED HOURLY TEMPERATURES TO REFLECT THIS. STILL EXPECT ONCE CLOUDS CLEAR...QUICK WARMING WILL ENSUE AND WILL MAINTAIN GOING HIGH TEMPERATURES THIS AFTERNOON. OTHERWISE...ONLY MINOR UPDATES WERE MADE TO HOURLY WINDS AND DEWPOINTS. THE MAIN CONCERN WILL BE FOR LOCALIZED HEAVY RAINFALL WHICH MAY LEAD TO FLASH FLOODING OVER PARTS OF WESTERN NORTH TEXAS. OTHERWISE...THE DAY SHOULD BE RELATIVELY QUIET AND MILD. DISCUSSION... PREV DISCUSSION... /ISSUED 652 AM CDT WED JUN 19 2013/ DISCUSSION... 12Z AVIATION DISCUSSION FOLLOWS BELOW... AVIATION... THUNDERSTORMS CONTINUE TO MOVE S/SE ACROSS THE TEXAS PANHANDLE AND FAR NORTHWESTERN OKLAHOMA THIS MORNING. THIS ACTIVITY WILL CONTINUE TO IMPACT KWWR AND KGAG THROUGH MID TO LATE MORNING. THIS ACTIVITY WILL SLOWLY DISSIPATE THROUGH NOON. THUNDERSTORM CHANCES WILL THEN INCREASE THROUGH THE AFTERNOON AND EVENING ACROSS NORTHERN OKLAHOMA. LOW CONFIDENCE ON TIMING AND LOCATION... THEREFORE...HAVE LEFT OUT A MENTION IN THE KWWR...KGAG...AND KPNC TAFS. THERE REMAINS A CHANCE OF MVFR STRATUS ACROSS THE SOUTHERN PORTIONS OF OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTERNOON...BUT CONFIDENCE REMAINS LOW...SO KEPT CEILINGS AT VFR AT THE MOMENT. WINDS WILL REMAIN OUT OF THE SOUTH...PICKING UP THROUGH NOON...WITH AFTERNOON GUSTS 20 TO 25 KTS AT TIMES. JTK PREV DISCUSSION... /ISSUED 347 AM CDT WED JUN 19 2013/ DISCUSSION... CURRENTLY...A WEAK MCS CONTINUES TO MOVE EASTWARD ACROSS SRN KS AND NWRN OK. THIS AREA OF CONVECTION REMAINS FOCUSED ALONG A LOW- LEVEL MOISTURE/THETA E AXIS POSITIONED ALONG/NEAR THE WRN KS/OK BORDER. OVERALL...MESOSCALE GUIDANCE HAS HAD A DIFFICULT GO THIS MORNING IN THE TRACK AND INTENSITY OF THESE STORMS. CURRENT THOUGHTS LEAN TOWARD THE MCS WEAKENING OVER THE NEXT FEW HOURS AS IT CONTINUES TO TRACK EASTWARD. CONDITIONS ARE LESS FAVORABLE FOR MCS MAINTENANCE ACROSS NRN AND CENTRAL OK...WHERE THE MOISTURE PROFILE IS LESS FAVORABLE AND MID-LEVEL LAPSE RATES WEAKEN CONSIDERABLY. THERE IS DECENT DEEP LAYER SHEAR...30-40KTS SPREAD INTO CENTRAL OK...BUT MUCAPES REMAIN LOW FOR MCS SUPPORT...700 TO 1000 J/KG. OVERALL...THE NEXT 12 TO 24 HOURS WILL POSE A FAIRLY DECENT CHALLENGE FORECASTWISE. THE RECENT 06Z RUN OF THE HRRR REVISES ITS PREVIOUS FORECAST...WITH CONVECTION DEVELOPING BEHIND THE MAIN LINE AND SURGING SOUTHWARD THROUGH THE TX PANHANDLE THROUGH THE MORNING. CURRENT RADAR TRENDS SUGGEST THIS MIGHT BE A POSSIBLE SCENARIO...AS NEW CONVECTION HAS STARTED TO DEVELOP OVER THE PAST HOUR...SINCE 230 AM...ACROSS SERN CO AND THE OK PANHANDLE. FOR THE MOMENT...WILL CONTINUE WITH CHANCE POPS ACROSS NWRN OK THROUGH THE MORNING HOURS. FOR THIS AFTERNOON...THE SHALLOW 500MB RIDGE WILL CONTINUE TO SHIFT/TILT EASTWARD ACROSS THE SRN PLAINS...WHILE ANOTHER LOW AMPLITUDE SHORTWAVE TRAVERSES THE REGION. WITH UPPER LEVEL SUPPORT...AND THE PAC NW TROUGH DIGGING EASTWARD...A STOUT SFC TROUGH/FRONT WILL EXTEND THE LENGTH OF THE FRONT RANGE INTO THE CENTRAL HIGH PLAINS. THIS COULD RESULT IN SOME WEAK SCATTERED CONVECTION LATER THIS AFTERNOON AND OVERNIGHT ACROSS NRN OK...PRIMARILY WELL NORTH OF THE I-40 AND I-44 CORRIDORS. EXPECT COVERAGE TO BE LIMITED WITH THIS SYSTEM...WITH MOST LOCATIONS LIKELY REMAINING DRY AFTER THIS MORNING. FOR THE REMAINDER OF THE WEEK...UPPER LEVEL RIDGING WILL TAKE HOLD...WITH SOUTH/SOUTHWEST FLOW SETTING UP SLOWLY THROUGH THE WEEKEND. TEMPERATURES WILL WARM BACK UP...WITH AFTERNOON HIGHS WELL INTO THE 90S...APPROACHING THE 100S ACROSS SWRN OK AND WRN N TX. THERE COULD BE A FEW ISOLATED SHOWERS ACROSS FAR NWRN OK SUNDAY AS THE WRN TROUGH INTENSIFIES AND A SFC FRONT APPROACHES THE REGION...BUT AT THE MOMENT...EXPECT THE GOOD MAJORITY OF THE AREA TO REMAIN DRY THROUGH THE WEEKEND. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 85 69 89 71 / 10 10 10 0 HOBART OK 90 70 96 72 / 30 10 10 10 WICHITA FALLS TX 90 72 95 73 / 30 10 0 0 GAGE OK 87 69 96 73 / 20 20 10 10 PONCA CITY OK 85 69 88 72 / 10 30 30 10 DURANT OK 88 71 91 72 / 10 10 10 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 84/23/23
AREA FORECAST DISCUSSION
NWS TULSA OK
1216 PM CDT WED JUN 19 2013 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. SMALL CHANCE OF THUNDERSTORMS OVER MAINLY NE OK AFTER 10Z...HIGHEST ODDS AT KBVO WHERE PROB30 THUNDER WILL BE CARRIED. && .PREV DISCUSSION... /ISSUED 1034 AM CDT WED JUN 19 2013/ DISCUSSION... THUNDERSTORM COMPLEX CONTINUES TO DIVE SOUTH ACROSS TX PANHANDLE THIS MORNING WITH SOME ASSOCIATED ANVIL CIRRUS SPREADING INTO FAR WESTERN REACHES OF THE FORECAST AREA. IN ADDITION A RELATIVE MOIST AXIS FROM ARKLATEX INTO NC OK ASSOCIATED WITH LOWER CLOUDS AND WHILE AN ISOLATED STORM OR TWO MAY DEVELOP IN THIS AREA...FEEL THAT WITH RISING MID LEVEL HEIGHTS THE OVERALL COVERAGE/PROB TOO LOW TO INCLUDE IN FORECAST. THIS MAY BECOME FOCUS FOR OVERNIGHT STORM COMPLEX DEVELOPING OVER CENTRAL PLAINS WHICH WILL HAVE A HIGHER THREAT OF MOVING INTO EASTERN OK BY EARLY THU MORNING HOWEVER. OVERALL FORECAST APPEARS ON TRACK AND WILL MAKE UPDATES FOR LESS CLOUD COVER ACROSS EASTERN AREAS AND TO INCORPORATE HOURLY TRENDS. PREV DISCUSSION... /ISSUED 617 AM CDT WED JUN 19 2013/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. THUNDERSTORM CHANCES APPEAR TOO LOW TO MENTION AT NE OK TAF SITES AT THIS TIME. PREV DISCUSSION... /ISSUED 303 AM CDT WED JUN 19 2013/ DISCUSSION... A RIDGE OF HIGH PRESSURE ALOFT WILL BEGIN TO NUDGE INTO THE AREA FROM THE SOUTHWEST TODAY. BEFORE WE GET INTO SOMETHING OF A DRY PERIOD...THE AREA WILL HAVE TO CONTEND WITH A COUPLE OF THUNDERSTORM COMPLEXES. THIS MORNING THERE IS THUNDERSTORM COMPLEX THAT EXTENDS FROM SOUTHWEST KANSAS INTO THE TEXAS PANHANDLE. THE LATEST HRRR SHOWS THIS COMPLEX MOVING INTO CENTRAL OKLAHOMA THIS MORNING AS IT DECAYS. HAVE LEFT POPS OUT OF THE FORECAST FOR TODAY BUT NOT FEELING OVERLY CONFIDENT ABOUT THIS DECISION. COULD SEE SOME REDEVELOPMENT ON THE OUTFLOW BOUNDARY CREATED BY THIS COMPLEX THIS AFTERNOON. ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP ACROSS WESTERN KANSAS AGAIN THIS AFTERNOON/EVENING AND MAKE A RUN AT NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS LATE TONIGHT INTO THURSDAY. DO HAVE POPS IN THE FORECAST TO ACCOUNT FOR THIS FEATURE AS THE MODELS HAVE BEEN CONSISTENTLY SHOWING THIS FOR SEVERAL RUNS. THE UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE AREA THROUGH THE WEEKEND. THERE ARE SOME SIGNS THAT THERE MAY BE ENOUGH WEAKNESS IN THE RIDGE THAT SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE SATURDAY AND SUNDAY AFTERNOONS IN THE FAVORED TERRAIN AREAS OF SOUTHEAST OKLAHOMA INTO NORTHWEST ARKANSAS. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...14
AREA FORECAST DISCUSSION
NWS NORMAN OK
1140 AM CDT WED JUN 19 2013 .UPDATE... MADE A FEW MINOR TWEAKS TO THE GOING FORECAST. SOUTHERN END OF ONGOING STORM COMPLEX HAS MOVED INTO FAR WESTERN NORTH TEXAS. HAVE UPPED POPS TO LIKELY OVER THIS AREA AND MAINTAIN CHANCE POPS THROUGH LATE AFTERNOON. THEREAFTER...ONLY ISOLATED ACTIVITY IS EXPECTED BEFORE ADDITIONAL STORMS DEVELOP THIS EVENING AND OVERNIGHT. GIVEN SUBSTANTIAL CLOUD COVER HAS LIMITED HEATING ACROSS SOUTHWEST OKLAHOMA AND NORTH TEXAS...HAVE TWEAKED HOURLY TEMPERATURES TO REFLECT THIS. STILL EXPECT ONCE CLOUDS CLEAR...QUICK WARMING WILL ENSUE AND WILL MAINTAIN GOING HIGH TEMPERATURES THIS AFTERNOON. OTHERWISE...ONLY MINOR UPDATES WERE MADE TO HOURLY WINDS AND DEWPOINTS. THE MAIN CONCERN WILL BE FOR LOCALIZED HEAVY RAINFALL WHICH MAY LEAD TO FLASH FLOODING OVER PARTS OF WESTERN NORTH TEXAS. OTHERWISE...THE DAY SHOULD BE RELATIVELY QUIET AND MILD. && .DISCUSSION... && .PREV DISCUSSION... /ISSUED 652 AM CDT WED JUN 19 2013/ DISCUSSION... 12Z AVIATION DISCUSSION FOLLOWS BELOW... AVIATION... THUNDERSTORMS CONTINUE TO MOVE S/SE ACROSS THE TEXAS PANHANDLE AND FAR NORTHWESTERN OKLAHOMA THIS MORNING. THIS ACTIVITY WILL CONTINUE TO IMPACT KWWR AND KGAG THROUGH MID TO LATE MORNING. THIS ACTIVITY WILL SLOWLY DISSIPATE THROUGH NOON. THUNDERSTORM CHANCES WILL THEN INCREASE THROUGH THE AFTERNOON AND EVENING ACROSS NORTHERN OKLAHOMA. LOW CONFIDENCE ON TIMING AND LOCATION... THEREFORE...HAVE LEFT OUT A MENTION IN THE KWWR...KGAG...AND KPNC TAFS. THERE REMAINS A CHANCE OF MVFR STRATUS ACROSS THE SOUTHERN PORTIONS OF OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTERNOON...BUT CONFIDENCE REMAINS LOW...SO KEPT CEILINGS AT VFR AT THE MOMENT. WINDS WILL REMAIN OUT OF THE SOUTH...PICKING UP THROUGH NOON...WITH AFTERNOON GUSTS 20 TO 25 KTS AT TIMES. JTK PREV DISCUSSION... /ISSUED 347 AM CDT WED JUN 19 2013/ DISCUSSION... CURRENTLY...A WEAK MCS CONTINUES TO MOVE EASTWARD ACROSS SRN KS AND NWRN OK. THIS AREA OF CONVECTION REMAINS FOCUSED ALONG A LOW- LEVEL MOISTURE/THETA E AXIS POSITIONED ALONG/NEAR THE WRN KS/OK BORDER. OVERALL...MESOSCALE GUIDANCE HAS HAD A DIFFICULT GO THIS MORNING IN THE TRACK AND INTENSITY OF THESE STORMS. CURRENT THOUGHTS LEAN TOWARD THE MCS WEAKENING OVER THE NEXT FEW HOURS AS IT CONTINUES TO TRACK EASTWARD. CONDITIONS ARE LESS FAVORABLE FOR MCS MAINTENANCE ACROSS NRN AND CENTRAL OK...WHERE THE MOISTURE PROFILE IS LESS FAVORABLE AND MID-LEVEL LAPSE RATES WEAKEN CONSIDERABLY. THERE IS DECENT DEEP LAYER SHEAR...30-40KTS SPREAD INTO CENTRAL OK...BUT MUCAPES REMAIN LOW FOR MCS SUPPORT...700 TO 1000 J/KG. OVERALL...THE NEXT 12 TO 24 HOURS WILL POSE A FAIRLY DECENT CHALLENGE FORECASTWISE. THE RECENT 06Z RUN OF THE HRRR REVISES ITS PREVIOUS FORECAST...WITH CONVECTION DEVELOPING BEHIND THE MAIN LINE AND SURGING SOUTHWARD THROUGH THE TX PANHANDLE THROUGH THE MORNING. CURRENT RADAR TRENDS SUGGEST THIS MIGHT BE A POSSIBLE SCENARIO...AS NEW CONVECTION HAS STARTED TO DEVELOP OVER THE PAST HOUR...SINCE 230 AM...ACROSS SERN CO AND THE OK PANHANDLE. FOR THE MOMENT...WILL CONTINUE WITH CHANCE POPS ACROSS NWRN OK THROUGH THE MORNING HOURS. FOR THIS AFTERNOON...THE SHALLOW 500MB RIDGE WILL CONTINUE TO SHIFT/TILT EASTWARD ACROSS THE SRN PLAINS...WHILE ANOTHER LOW AMPLITUDE SHORTWAVE TRAVERSES THE REGION. WITH UPPER LEVEL SUPPORT...AND THE PAC NW TROUGH DIGGING EASTWARD...A STOUT SFC TROUGH/FRONT WILL EXTEND THE LENGTH OF THE FRONT RANGE INTO THE CENTRAL HIGH PLAINS. THIS COULD RESULT IN SOME WEAK SCATTERED CONVECTION LATER THIS AFTERNOON AND OVERNIGHT ACROSS NRN OK...PRIMARILY WELL NORTH OF THE I-40 AND I-44 CORRIDORS. EXPECT COVERAGE TO BE LIMITED WITH THIS SYSTEM...WITH MOST LOCATIONS LIKELY REMAINING DRY AFTER THIS MORNING. FOR THE REMAINDER OF THE WEEK...UPPER LEVEL RIDGING WILL TAKE HOLD...WITH SOUTH/SOUTHWEST FLOW SETTING UP SLOWLY THROUGH THE WEEKEND. TEMPERATURES WILL WARM BACK UP...WITH AFTERNOON HIGHS WELL INTO THE 90S...APPROACHING THE 100S ACROSS SWRN OK AND WRN N TX. THERE COULD BE A FEW ISOLATED SHOWERS ACROSS FAR NWRN OK SUNDAY AS THE WRN TROUGH INTENSIFIES AND A SFC FRONT APPROACHES THE REGION...BUT AT THE MOMENT...EXPECT THE GOOD MAJORITY OF THE AREA TO REMAIN DRY THROUGH THE WEEKEND. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 85 69 89 71 / 10 10 10 0 HOBART OK 90 70 96 72 / 30 10 10 10 WICHITA FALLS TX 90 72 95 73 / 30 10 0 0 GAGE OK 87 69 96 73 / 20 20 10 10 PONCA CITY OK 85 69 88 72 / 10 30 30 10 DURANT OK 88 71 91 72 / 10 10 10 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 84/23
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
422 PM EDT WED JUN 19 2013 .SYNOPSIS... COOLER HIGH PRESSURE CENTERED NEAR NEW YORK STATE WILL RIDGE SOUTHWARD TONIGHT AND THURSDAY. THIS HIGH WILL DRIFT TO NEAR BERMUDA AND INTO NEXT WEEK AS AN UPPER RIDGE BUILDS IN FROM THE WEST AS TEMPERATURES SLOWLY RISE. && .NEAR TERM /THROUGH THURSDAY/... 2030 UTC UPDATE...POPS WERE ADJUSTED IN THE THE NORTHERN NC MOUNTAINS AND THE UPPER SAVANNAH RIVER VALLEY THE LATEST PER RADAR TRENDS. AS OF 215 PM...A WEAK SHORT WAVE TROUGH IS FORECAST TO MOVE THROUGH THE AREA FROM NW TO SE LATE THIS AFTERNOON AND EARLY TONIGHT. THE BEST FORCING WILL BE OVER THE FAR EASTERN AREAS. HENCE...THE MODELS SHOW SOME LIGHT QPF RESPONSE THERE. THE LATEST HRRR SHOWS THE MOST SHOWER COVERAGE FROM THE NORTHERN MOUNTAINS...EAST THROUGH THE NORTHERN NC PIEDMONT. WILL MAKE A LAST MINUTE ADJUSTMENT ON THE POP FIELD TO REFLECT THAT IDEA. WIDELY SCT SHOWERS/THUNDERSTORMS ARE EXPECTED ELSEWHERE THROUGH THE MOUNTAINS DURING THE MID TO LATE AFTERNOON HOURS DUE TO WEAK UPSLOPE FLOW. CAPES SHOULD GENERALLY STAY BELOW 1000J AS SOMEWHAT LOWER DEWPOINTS CONTINUE TO ADVECT INTO THE REGION...SO NO SEVERE THREAT. THE SHOWERS ARE EXPECTED TO DISSIPATE DURING EVENING. OTHERWISE...THE OVERNIGHT SHOULD BE QUIET. MODEL TIME HEIGHTS SHOW LOW LEVEL MOISTURE INCREASING TOWARD SUNRISE AS MOISTURE FROM ATLANTIC ADVECTS INTO THE AREA. THEREFORE...EXPECT A PERIOD OF LOW CLOUDINESS EARLY THU...ESPECIALLY EAST OF I-26. ON THU...HIGH PRESSURE LOCATED OFF THE NEW ENGLAND COAST WILL REMAIN RIDGED INTO THE AREA PRODUCING AN EASTERLY WIND FLOW IN THE SOUTHERN APPALACHIANS. THE UPSLOPE FLOW IN THE MOUNTAINS SHOULD PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS. USING A BLEND OF MODELS PRODUCES MAX TEMPS ABOUT A CATEGORY BELOW AVERAGE ON THU. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 210 PM EDT WED...SHORT RANGE MODELS AGREE THAT THE REGION WILL REMAIN UNDER A WEAK MID LEVEL TROUGH...WITH RIDGING ACROSS THE SOUTHERN PLAINS AND ATLANTIC. AT THE SFC...A STATIONARY FRONT AND POSSIBLE FRONTAL WAVE WILL REMAIN ACROSS THE COASTAL PLAIN OF THE CAROLINAS. WEAK SFC RIDGING MAY REMAIN ACROSS THE SOUTHERN APPALACHIAN REGION. GIVEN THE SFC PATTERN...I WILL INDICATE PERSISTENT NE WINDS ACROSS THE FOOTHILLS AND PIEDMONT FOR FRIDAY AND SATURDAY. A BLEND OF MODEL GUIDANCE INDICATES THAT SKY COVER WILL REMAIN PARTLY TO MOSTLY CLOUDY THROUGH THE PERIOD. THE COMBINATION OF NE WINDS AND CLOUD COVER SHOULD YIELD TEMPERATURES 3 TO 5 DEGREES BELOW NORMAL. OVERALL...THE CHCS OF SHRA AND TSRA APPEARS UNFAVORABLE WITHIN THE CORRIDOR OF DEEP NE FLOW. IN FACT...MODEL CAPE FIELDS INDICATE LITTLE TO NO VALUES FOR SFC BASED PARCELS BETWEEN THE EAST FACING MTN SLOPES TO THE WESTERN PIEDMONT. I WILL INDICATE SCHC POPS FOR TS ACROSS THE EXTREME WESTERN NC MTNS ON FRI AND SAT. BY SAT...LLVL WINDS MAY VEER NE...POSSIBLY ALLOWING WEAK INSTABILITY ACROSS NE GA AND THE EASTERN PIEDMONT DURING THE LATE AFTERNOON. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 240 PM EDT WED...A 591 DM H5 RIDGE WILL REMAIN DOMINANT OVER THE SE THROUGH THE MEDIUM RANGE PERIOD. ANTICIPATE A MAINLY DIURNAL TREND OF ISOLD TO SCATTERED AFTERNOON POPS THROUGH THE PERIOD...WITH THE MTNS BEING THE PRIMARY FOCUS. THE GFS IS THE MOST AGGRESSIVE IN BRINGING AN INVERTED COASTAL TROUGH BACK INLAND ALONG THE SAVANNAH ON SATURDAY...BUT THE OTHER OPERATIONAL AND ENSEMBLE MEAN SOLUTIONS KEEP THE SYSTEM ALONG THE IMMEDIATE COAST WITH THE RIDGE PERSISTING OVER THE WRN CAROLINAS. THE DIURNAL PATTERN OF ISOLD TO SCT SHOWERS AND THUNDERSTORMS SHOULD THUS CONTINUE SUN THROUGH TUE...WITH TEMPERATURES STEADILY WARMING UNDER THE UPPER RIDGE. EXPECT MAXES TO REACH CLIMATE NORMALS BY SUNDAY AND THEN EXCEED THEM MON AND TUE. THE UPPER RIDGE WILL BREAK DOWN IN MID WEEK AS A UPPER TROUGH FORMS OVER THE EAST COAST FOR THE SECOND HALF OF NEXT WEEK. THE GFS IS A BIT MORE PROGRESSIVE IN BRINGING THE TROUGH IN SOONER BY LATE WED OR WED NIGHT AS OPPOSED TO THUR OR FRI ON THE ECMWF. TEMPS ARE EXPECTED TO COOL SOME AS THIS TROUGH SETS UP WITH MORE CLOUDS AND HIGHER POPS. && .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... AT KCLT...SCT-BKN CU IS EXPECTED THROUGH THE AFTERNOON. CONVECTIVE CHANCES STILL SEEM TOO LOW TO MENTION IN THE TAF. SOME SHRA ASSOCIATED WITH A WEAK BACKDOOR FRONT WILL PROBABLY BE NOTED ON RADAR WELL TO THE NORTH OF THE FIELD LATE THIS AFTERNOON. MOST GUIDANCE SUGGESTS THAT STRATUS WILL ARRIVE FROM THE E-NE LATE TONIGHT. HENCE...HAVE INTRODCUED A BKN016 BEGINNING AT 11Z. THE STRATUS SHOULD THEN SCT BY 15Z. ELSEWHERE...IT APPEARS CONVECTIVE CHANCES WILL BE MOSTLY LIMITED TO WIDELY SCATTERED SHOWERS/THUDNERSTORMS OVER THE MOUNTAINS AND NC FOOTHILLS. HOWEVER...CHANCES TOO LOW TO MENTION EXCEPT FOR A VCSH AT KAVL LATE THIS AFTERNOON. BKN VFR CU WILL SCT THIS EVENING. GUIDANCE IS ADVERTISING A STRATUS DECK TO ARRIVE FROM THE E-NE LATE TONIGHT AND IS EXPECTED TO AFFECT ALL AIRFIELDS WITH AT LEAST MVFR CIGS FOR SEVERAL HOURS EARLY THU...EXCEPT KAND. OUTLOOK...INCREASING MOISTURE TOWARDS THE END OF THE WORK WEEK WILL ALLOW DIURNAL CONVECTION TO DEVELOP EACH AFTERNOON....MAINLY OVER THE MOUNTAINS. GENRALLY VFR CONDITIONS ARE EXPECTED EXCEPT SOME EARLY MORNING STRATUS IS POSSIBLE EACH DAY. DEEP ATLANTIC MOISTURE WILL ARRIVE THIS WEEKEND PROMOTING MORE WIDESPREAD SHOWERS AND THUNDERSTORMS AND MORE RESTRICTIONS. CONFIDENCE TABLE... 20-02Z 02-08Z 08-14Z 14-20Z KCLT HIGH 100% HIGH 100% HIGH 89% HIGH 95% KGSP HIGH 100% HIGH 100% HIGH 86% HIGH 95% KAVL HIGH 100% HIGH 94% HIGH 89% HIGH 91% KHKY HIGH 100% HIGH 100% MED 72% HIGH 96% KGMU HIGH 100% HIGH 100% HIGH 86% HIGH 98% KAND HIGH 100% HIGH 88% HIGH 81% HIGH 98% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...DEO NEAR TERM...JAT/LG SHORT TERM...NED LONG TERM...DEO AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
327 PM EDT WED JUN 19 2013 .SYNOPSIS... COOLER HIGH PRESSURE CENTERED NEAR NEW YORK STATE WILL RIDGE SOUTHWARD TONIGHT AND THURSDAY. THIS HIGH WILL DRIFT TO NEAR BERMUDA AND INTO NEXT WEEK AS AN UPPER RIDGE BUILDS IN FROM THE WEST AS TEMPERATURES SLOWLY RISE. && .NEAR TERM /THROUGH THURSDAY/... 1930 UTC UPDATE...SKY COVER HAS BEEN UPDATED FROM THE LATEST VISIBLE SATELLITE IMAGERY. POPS WERE RAISED IN THE THE NORTHERN NC MOUNTAINS...AND THE UPPER SAVANNAH RIVER VALLEY...PER RADAR TRENDS. AS OF 215 PM...A WEAK SHORT WAVE TROUGH IS FORECAST TO MOVE THROUGH THE AREA FROM NW TO SE LATE THIS AFTERNOON AND EARLY TONIGHT. THE BEST FORCING WILL BE OVER THE FAR EASTERN AREAS. HENCE...THE MODELS SHOW SOME LIGHT QPF RESPONSE THERE. THE LATEST HRRR SHOWS THE MOST SHOWER COVERAGE FROM THE NORTHERN MOUNTAINS...EAST THROUGH THE NORTHERN NC PIEDMONT. WILL MAKE A LAST MINUTE ADJUSTMENT ON THE POP FIELD TO REFLECT THAT IDEA. WIDELY SCT SHOWERS/THUNDERSTORMS ARE EXPECTED ELSEWHERE THROUGH THE MOUNTAINS DURING THE MID TO LATE AFTERNOON HOURS DUE TO WEAK UPSLOPE FLOW. CAPES SHOULD GENERALLY STAY BELOW 1000J AS SOMEWHAT LOWER DEWPOINTS CONTINUE TO ADVECT INTO THE REGION...SO NO SEVERE THREAT. THE SHOWERS ARE EXPECTED TO DISSIPATE DURING EVENING. OTHERWISE...THE OVERNIGHT SHOULD BE QUIET. MODEL TIME HEIGHTS SHOW LOW LEVEL MOISTURE INCREASING TOWARD SUNRISE AS MOISTURE FROM ATLANTIC ADVECTS INTO THE AREA. THEREFORE...EXPECT A PERIOD OF LOW CLOUDINESS EARLY THU...ESPECIALLY EAST OF I-26. ON THU...HIGH PRESSURE LOCATED OFF THE NEW ENGLAND COAST WILL REMAIN RIDGED INTO THE AREA PRODUCING AN EASTERLY WIND FLOW IN THE SOUTHERN APPALACHIANS. THE UPSLOPE FLOW IN THE MOUNTAINS SHOULD PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS. USING A BLEND OF MODELS PRODUCES MAX TEMPS ABOUT A CATEGORY BELOW AVERAGE ON THU. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 210 PM EDT WED...SHORT RANGE MODELS AGREE THAT THE REGION WILL REMAIN UNDER A WEAK MID LEVEL TROUGH...WITH RIDGING ACROSS THE SOUTHERN PLAINS AND ATLANTIC. AT THE SFC...A STATIONARY FRONT AND POSSIBLE FRONTAL WAVE WILL REMAIN ACROSS THE COASTAL PLAIN OF THE CAROLINAS. WEAK SFC RIDGING MAY REMAIN ACROSS THE SOUTHERN APPALACHIAN REGION. GIVEN THE SFC PATTERN...I WILL INDICATE PERSISTENT NE WINDS ACROSS THE FOOTHILLS AND PIEDMONT FOR FRIDAY AND SATURDAY. A BLEND OF MODEL GUIDANCE INDICATES THAT SKY COVER WILL REMAIN PARTLY TO MOSTLY CLOUDY THROUGH THE PERIOD. THE COMBINATION OF NE WINDS AND CLOUD COVER SHOULD YIELD TEMPERATURES 3 TO 5 DEGREES BELOW NORMAL. OVERALL...THE CHCS OF SHRA AND TSRA APPEARS UNFAVORABLE WITHIN THE CORRIDOR OF DEEP NE FLOW. IN FACT...MODEL CAPE FIELDS INDICATE LITTLE TO NO VALUES FOR SFC BASED PARCELS BETWEEN THE EAST FACING MTN SLOPES TO THE WESTERN PIEDMONT. I WILL INDICATE SCHC POPS FOR TS ACROSS THE EXTREME WESTERN NC MTNS ON FRI AND SAT. BY SAT...LLVL WINDS MAY VEER NE...POSSIBLY ALLOWING WEAK INSTABILITY ACROSS NE GA AND THE EASTERN PIEDMONT DURING THE LATE AFTERNOON. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 240 PM EDT WED...A 591 DM H5 RIDGE WILL REMAIN DOMINANT OVER THE SE THROUGH THE MEDIUM RANGE PERIOD. ANTICIPATE A MAINLY DIURNAL TREND OF ISOLD TO SCATTERED AFTERNOON POPS THROUGH THE PERIOD...WITH THE MTNS BEING THE PRIMARY FOCUS. THE GFS IS THE MOST AGGRESSIVE IN BRINGING AN INVERTED COASTAL TROUGH BACK INLAND ALONG THE SAVANNAH ON SATURDAY...BUT THE OTHER OPERATIONAL AND ENSEMBLE MEAN SOLUTIONS KEEP THE SYSTEM ALONG THE IMMEDIATE COAST WITH THE RIDGE PERSISTING OVER THE WRN CAROLINAS. THE DIURNAL PATTERN OF ISOLD TO SCT SHOWERS AND THUNDERSTORMS SHOULD THUS CONTINUE SUN THROUGH TUE...WITH TEMPERATURES STEADILY WARMING UNDER THE UPPER RIDGE. EXPECT MAXES TO REACH CLIMATE NORMALS BY SUNDAY AND THEN EXCEED THEM MON AND TUE. THE UPPER RIDGE WILL BREAK DOWN IN MID WEEK AS A UPPER TROUGH FORMS OVER THE EAST COAST FOR THE SECOND HALF OF NEXT WEEK. THE GFS IS A BIT MORE PROGRESSIVE IN BRINGING THE TROUGH IN SOONER BY LATE WED OR WED NIGHT AS OPPOSED TO THUR OR FRI ON THE ECMWF. TEMPS ARE EXPECTED TO COOL SOME AS THIS TROUGH SETS UP WITH MORE CLOUDS AND HIGHER POPS. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... AT KCLT...SCT-BKN CU IS EXPECTED THROUGH THE AFTERNOON. CONVECTIVE CHANCES STILL SEEM TOO LOW TO MENTION IN THE TAF. SOME SHRA ASSOCIATED WITH A WEAK BACKDOOR FRONT WILL PROBABLY BE NOTED ON RADAR WELL TO THE NORTH OF THE FIELD LATE THIS AFTERNOON. MOST GUIDANCE SUGGESTS THAT STRATUS WILL ARRIVE FROM THE E-NE LATE TONIGHT. HENCE...HAVE INTRODCUED A BKN016 BEGINNING AT 11Z. THE STRATUS SHOULD THEN SCT BY 15Z. ELSEWHERE...IT APPEARS CONVECTIVE CHANCES WILL BE MOSTLY LIMITED TO WIDELY SCATTERED SHOWERS/THUDNERSTORMS OVER THE MOUNTAINS AND NC FOOTHILLS. HOWEVER...CHANCES TOO LOW TO MENTION EXCEPT FOR A VCSH AT KAVL LATE THIS AFTERNOON. BKN VFR CU WILL SCT THIS EVENING. GUIDANCE IS ADVERTISING A STRATUS DECK TO ARRIVE FROM THE E-NE LATE TONIGHT AND IS EXPECTED TO AFFECT ALL AIRFIELDS WITH AT LEAST MVFR CIGS FOR SEVERAL HOURS EARLY THU...EXCEPT KAND. OUTLOOK...INCREASING MOISTURE TOWARDS THE END OF THE WORK WEEK WILL ALLOW DIURNAL CONVECTION TO DEVELOP EACH AFTERNOON....MAINLY OVER THE MOUNTAINS. GENRALLY VFR CONDITIONS ARE EXPECTED EXCEPT SOME EARLY MORNING STRATUS IS POSSIBLE EACH DAY. DEEP ATLANTIC MOISTURE WILL ARRIVE THIS WEEKEND PROMOTING MORE WIDESPREAD SHOWERS AND THUNDERSTORMS AND MORE RESTRICTIONS. CONFIDENCE TABLE... 19-01Z 01-07Z 07-13Z 13-19Z KCLT HIGH 100% HIGH 100% HIGH 86% HIGH 91% KGSP HIGH 92% HIGH 100% HIGH 86% HIGH 91% KAVL HIGH 100% HIGH 95% HIGH 84% HIGH 90% KHKY HIGH 100% HIGH 100% MED 70% HIGH 96% KGMU HIGH 92% HIGH 100% HIGH 86% HIGH 96% KAND HIGH 100% HIGH 95% HIGH 85% HIGH 98% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...DEO NEAR TERM...JAT/LG SHORT TERM...NED LONG TERM...DEO AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
237 PM EDT WED JUN 19 2013 .SYNOPSIS... COOLER HIGH PRESSURE CENTERED NEAR NEW YORK STATE WILL RIDGE SOUTHWARD TONIGHT AND THURSDAY. THIS HIGH WILL DRIFT TO NEAR BERMUDA AND INTO NEXT WEEK AS AN UPPER RIDGE BUILDS IN FROM THE WEST AS TEMPERATURES SLOWLY RISE. && .NEAR TERM /THROUGH THURSDAY/... AS OF 215PM...A WEAK SHORT WAVE TROUGH IS FORECAST TO MOVE THROUGH THE AREA FROM NW TO SE LATE THIS AFTERNOON AND EARLY TONIGHT. THE BEST FORCING WILL BE OVER THE FAR EASTERN AREAS. HENCE...THE MODELS SHOW SOME LIGHT QPF RESPONSE THERE. THE LATEST HRRR SHOWS THE MOST SHOWER COVERAGE FROM THE NORTHERN MOUNTAINS...EAST THROUGH THE NORTHERN NC PIEDMONT. WILL MAKE A LAST MINUTE ADJUSTMENT ON THE POP FIELD TO REFLECT THAT IDEA. WIDELY SCT SHOWERS/THUNDERSTORMS ARE EXPECTED ELSEWHERE THROUGH THE MOUNTAINS DURING THE MID TO LATE AFTERNOON HOURS DUE TO WEAK UPSLOPE FLOW. CAPES SHOULD GENERALLY STAY BELOW 1000J AS SOMEWHAT LOWER DEWPOINTS CONTINUE TO ADVECT INTO THE REGION...SO NO SEVERE THREAT. THE SHOWERS ARE EXPECTED TO DISSIPATE DURING EVENING. OTHERWISE...THE OVERNIGHT SHOULD BE QUIET. MODEL TIME HEIGHTS SHOW LOW LEVEL MOISTURE INCREASING TOWARD SUNRISE AS MOISTURE FROM ATLANTIC ADVECTS INTO THE AREA. THEREFORE...EXPECT A PERIOD OF LOW CLOUDINESS EARLY THU...ESPECIALLY EAST OF I-26. ON THU...HIGH PRESSURE LOCATED OFF THE NEW ENGLAND COAST WILL REMAIN RIDGED INTO THE AREA PRODUCING AN EASTERLY WIND FLOW IN THE SOUTHERN APPALACHIANS. THE UPSLOPE FLOW IN THE MOUNTAINS SHOULD PRODUCE SCATTERED SHOWERS AND THUDNERSTORMS DURING THE AFTERNOON HOURS. USING A BLEND OF MODELS PRODUCES MAX TEMPS ABOUT A CATEGORY BELOW AVERAGE ON THU. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 210 PM EDT WED...SHORT RANGE MODELS AGREE THAT THE REGION WILL REMAIN UNDER A WEAK MID LEVEL TROUGH...WITH RIDGING ACROSS THE SOUTHERN PLAINS AND ATLANTIC. AT THE SFC...A STATIONARY FRONT AND POSSIBLE FRONTAL WAVE WILL REMAIN ACROSS THE COASTAL PLAIN OF THE CAROLINAS. WEAK SFC RIDGING MAY REMAIN ACROSS THE SOUTHERN APPALACHIAN REGION. GIVEN THE SFC PATTERN...I WILL INDICATE PERSISTENT NE WINDS ACROSS THE FOOTHILLS AND PIEDMONT FOR FRIDAY AND SATURDAY. A BLEND OF MODEL GUIDANCE INDICATES THAT SKY COVER WILL REMAIN PARTLY TO MOSTLY CLOUDY THROUGH THE PERIOD. THE COMBINATION OF NE WINDS AND CLOUD COVER SHOULD YIELD TEMPERATURES 3 TO 5 DEGREES BELOW NORMAL. OVERALL...THE CHCS OF SHRA AND TSRA APPEARS UNFAVORABLE WITHIN THE CORRIDOR OF DEEP NE FLOW. IN FACT...MODEL CAPE FIELDS INDICATE LITTLE TO NO VALUES FOR SFC BASED PARCELS BETWEEN THE EAST FACING MTN SLOPES TO THE WESTERN PIEDMONT. I WILL INDICATE SCHC POPS FOR TS ACROSS THE EXTREME WESTERN NC MTNS ON FRI AND SAT. BY SAT...LLVL WINDS MAY VEER NE...POSSIBLY ALLOWING WEAK INSTABILITY ACROSS NE GA AND THE EASTERN PIEDMONT DURING THE LATE AFTERNOON. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 240 PM EDT WED...A 591 DM H5 RIDGE WILL REMAIN DOMINANT OVER THE SE THROUGH THE MEDIUM RANGE PERIOD. ANTICIPATE A MAINLY DIURNAL TREND OF ISOLD TO SCATTERED AFTERNOON POPS THROUGH THE PERIOD...WITH THE MTNS BEING THE PRIMARY FOCUS. THE GFS IS THE MOST AGGRESSIVE IN BRINGING AN INVERTED COASTAL TROUGH BACK INLAND ALONG THE SAVANNAH ON SATURDAY...BUT THE OTHER OPERATIONAL AND ENSEMBLE MEAN SOLUTIONS KEEP THE SYSTEM ALONG THE IMMEDIATE COAST WITH THE RIDGE PERSISTING OVER THE WRN CAROLINAS. THE DIURNAL PATTERN OF ISOLD TO SCT SHOWERS AND THUNDERSTORMS SHOULD THUS CONTINUE SUN THROUGH TUE...WITH TEMPERATURES STEADILY WARMING UNDER THE UPPER RIDGE. EXPECT MAXES TO REACH CLIMATE NORMALS BY SUNDAY AND THEN EXCEED THEM MON AND TUE. THE UPPER RIDGE WILL BREAK DOWN IN MID WEEK AS A UPPER TROUGH FORMS OVER THE EAST COAST FOR THE SECOND HALF OF NEXT WEEK. THE GFS IS A BIT MORE PROGRESSIVE IN BRINGING THE TROUGH IN SOONER BY LATE WED OR WED NIGHT AS OPPOSED TO THUR OR FRI ON THE ECMWF. TEMPS ARE EXPECTED TO COOL SOME AS THIS TROUGH SETS UP WITH MORE CLOUDS AND HIGHER POPS. && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... AT KCLT...SCT-BKN CU IS EXPECTED THROUGH THE AFTERNOON. CONVECTIVE CHANCES STILL SEEM TOO LOW TO MENTION IN THE TAF. SOME SHRA ASSOCIATED WITH A WEAK BACKDOOR FRONT WILL PROBABLY BE NOTED ON RADAR WELL TO THE NORTH OF THE FIELD LATE THIS AFTERNOON. MOST GUIDANCE SUGGESTS THAT STRATUS WILL ARRIVE FROM THE E-NE LATE TONIGHT. HENCE...HAVE INTRODCUED A BKN016 BEGINNING AT 11Z. THE STRATUS SHOULD THEN SCT BY 15Z. ELSEWHERE...IT APPEARS CONVECTIVE CHANCES WILL BE MOSTLY LIMITED TO WIDELY SCATTERED SHOWERS/THUDNERSTORMS OVER THE MOUNTAINS AND NC FOOTHILLS. HOWEVER...CHANCES TOO LOW TO MENTION EXCEPT FOR A VCSH AT KAVL LATE THIS AFTERNOON. BKN VFR CU WILL SCT THIS EVENING. GUIDANCE IS ADVERTISING A STRATUS DECK TO ARRIVE FROM THE E-NE LATE TONIGHT AND IS EXPECTED TO AFFECT ALL AIRFIELDS WITH AT LEAST MVFR CIGS FOR SEVERAL HOURS EARLY THU...EXCEPT KAND. OUTLOOK...INCREASING MOISTURE TOWARDS THE END OF THE WORK WEEK WILL ALLOW DIURNAL CONVECTION TO DEVELOP EACH AFTERNOON....MAINLY OVER THE MOUNTAINS. GENRALLY VFR CONDITIONS ARE EXPECTED EXCEPT SOME EARLY MORNING STRATUS IS POSSIBLE EACH DAY. DEEP ATLANTIC MOISTURE WILL ARRIVE THIS WEEKEND PROMOTING MORE WIDESPREAD SHOWERS AND THUNDERSTORMS AND MORE RESTRICTIONS. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 89% HIGH 88% KGSP HIGH 85% HIGH 100% HIGH 89% HIGH 88% KAVL HIGH 100% HIGH 100% HIGH 81% HIGH 93% KHKY HIGH 100% HIGH 100% MED 71% HIGH 96% KGMU HIGH 92% HIGH 100% HIGH 89% HIGH 93% KAND HIGH 100% HIGH 100% HIGH 87% HIGH 92% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...DEO NEAR TERM...LG SHORT TERM...NED LONG TERM...DEO AVIATION...LG
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
340 PM CDT WED JUN 19 2013 .SHORT TERM... STRONG TO SEVERE CONVECTION IS ONGOING ACROSS THE BIG COUNTRY THIS AFTERNOON. THIS ACTIVITY IS OCCURRING IN THE VICINITY OF A SLOWLY SOUTHWARD MOVING SURFACE BOUNDARY DRAPED FROM NORTHWEST TO SOUTHEAST FROM NEAR LAMESA...TO SWEETWATER...TO BRECKENRIDGE. THE ENVIRONMENT IS QUITE UNSTABLE...AS EVIDENT FROM THE MLCAPE VALUES AT OR ABOVE 3000 J/KG. EFFECTIVE SHEAR VALUES OF NEAR 40 KTS HAVE MAINTAINED ORGANIZATION IN THIS CONVECTION WITH AT LEAST TWO SUPERCELLS EMBEDDED WITHIN THE CLUSTER. THIS ACTIVITY WILL CONTINUE TO MOVE TO THE SOUTHEAST THIS AFTERNOON...LINGERING INTO THE EVENING HOURS AND MAINLY AFFECTING THE BIG COUNTRY AND NORTHERN HEARTLAND. I HAVE NOTED THE HRRR INDICATING A LATE NIGHT PRECIP POTENTIAL FOR THE CONCHO VALLEY BUT I AM PLAYING THIS MORE CONSERVATIVE AND KEEPING THE FORECAST DRY FOR THE SOUTHERN COUNTIES. EXPECT OVERNIGHT LOWS GENERALLY IN THE LOWER 70S. HOWEVER...SOME RAIN COOLED AREAS WILL LIKELY DIP INTO THE 60S. TOMORROW...THE RIDGE IS EXPECTED TO TAKE CONTROL WITH HOT AND DRY CONDITIONS AREAWIDE. TEMPS WILL WARM INTO THE MID 90S ACROSS WEST CENTRAL TX WITH SOUTH WINDS OF 15-20 MPH. .LONG TERM... A STEADY-STATE PATTERN OF HOT AND DRY CONDITIONS ARE EXPECTED FOR WEST CENTRAL TEXAS...FRIDAY THROUGH THE MIDDLE OF NEXT WEEK. SUBTROPICAL RIDGE WILL BE OUR DOMINANT WEATHER INFLUENCE. THIS FEATURE WILL BUILD/EXPAND NORTHEAST FROM TEXAS TOWARD THE LOWER GREAT LAKES ON FRIDAY...AND WILL REMAIN ANCHORED OVER TEXAS THROUGH THE WEEKEND AND FIRST PART OF NEXT WEEK. BY THE MIDDLE OF NEXT WEEK...THE GFS AND ECMWF SHIFT THE CENTER OF THE UPPER HIGH NORTHWEST INTO NEW MEXICO AND COLORADO. ASSOCIATED SUBSIDENCE WILL HELP TO KEEP OUR RAIN CHANCES MINIMAL. THE LOW-LEVEL THERMAL RIDGE WILL REMAIN CENTERED TO OUR WEST... WITH SOME EASTWARD EXPANSION INDICATED NEXT WEEK. WITH THIS PATTERN AND INCREASED SOIL MOISTURE FROM RECENT RAINFALL AND EVAPOTRANSPIRATIVE EFFECTS...EXPECT LITTLE CHANGE IN THE DAILY TEMPERATURES THROUGH MONDAY. COULD HAVE MAXIMUM TEMPERATURES CREEPING UP A FEW DEGREES AS THE WEEK PROGRESSES HOWEVER. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 73 95 73 95 73 / 20 0 0 0 0 SAN ANGELO 73 96 72 96 72 / 5 0 0 0 0 JUNCTION 71 94 71 93 71 / 0 0 0 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ JOHNSON/19
AREA FORECAST DISCUSSION
NWS AMARILLO TX
328 PM CDT WED JUN 19 2013 .DISCUSSION... MORNING CONVECTION HAS HELPED TO STABILIZE THE TEXAS AND OKLAHOMA PANHANDLES WHICH COULD KEEP PRECIPITATION CHANCES LIMITED THIS EVENING AND TONIGHT. CONVECTION IS ALREADY BEGINNING TO DEVELOP OVER THE NEW MEXICO MOUNTAINS THIS AFTERNOON. THE OUTFLOW FROM OUR STORMS THIS MORNING HAS PROGRESSED INTO THE EASTERN NEW MEXICO PLAINS BEFORE LOSING FORWARD MOMENTUM. THE RUC HRRR HAS BEEN ADVERTISING THAT CONVECTION WOULD DEVELOP ALONG THE WESTERN EXTENT OF THE OUTFLOW AND COMBINE WITH STORMS OVER NEW MEXICO BEFORE MOVING ACROSS THE CENTRAL AND SOUTHERN PANHANDLES. HOWEVER...THE RUC HRRR HAS CONSISTENTLY SHOWN THE MCS OVER NORTHWESTERN TEXAS TAKING A MUCH FURTHER EAST TRACK WHILE NOT PROGRESSING THE WESTERN OUTFLOW FAR ENOUGH WEST. THIS ARGUES THAT IF CONVECTION DOES FORM ALONG THE WESTERN OUTFLOW IT WILL HAVE TO STRUGGLE AGAINST THE OUTFLOW PROGRESS EASTWARD ENOUGH TO REACH THE PANHANDLES. HAVE KEPT POPS LOW AND USED AREAL QUANTIFIERS FOR THIS AFTERNOON THROUGH TONIGHT. IF THE STORMS OVER NEW MEXICO CAN OBTAIN STRONG COLD POOLS THEN THEY COULD OVERTAKE THE OUTFLOW AND TAP INTO ELEVATED INSTABILITY AS THEY MOVE INTO THE WESTERN TEXAS AND OKLAHOMA PANHANDLES. STRONG TO SEVERE STORMS MAY BE POSSIBLE IF THIS HAPPENS WITH HAIL AND DAMAGING WINDS AS THE PRIMARY SEVERE HAZARDS. ALSO GIVEN AMPLE PWATS ACROSS THE AREA...1.0 TO 1.2 INCHES...ANY STORM THAT MOVES INTO THE TEXAS OR OKLAHOMA PANHANDLE WILL HAVE A HEAVY RAIN POTENTIAL THAT COULD LEAD TO FLOODING AND FLASH FLOODING CONCERNS. ANY CONVECTIVE ACTIVITY THAT OCCURS ACROSS THE PANHANDLES THIS AFTERNOON/EVENING SHOULD DIMINISH AFTER MIDNIGHT. SATURDAY WILL SEE THE RIDGE AXIS SHIFT TO THE EAST OF THE PANHANDLES AND OPEN UP THE WESTERN PANHANDLES TO ANOTHER CHANCE FOR PRECIPITATION DURING THE AFTERNOON AND EVENING HOURS. WITH CAPE VALUES OF 1500 TO 2500 J/KG BUT WEAK DEEP LAYER SHEAR COULD LEAD TO A FEW STORMS BRIEFLY PULSING TO STRONG TO SEVERE LEVELS THEN COLLAPSING. THIS WILL KEEP THE RISK FOR DAMAGING WINDS AND HAIL AS THE PRIMARY HAZARDS. FRIDAY AFTERNOON WILL BE SIMILAR TO THURSDAY/S WITH DECENT CAPE VALUES BUT VERY WEAK DEEP LAYER SHEAR. STRONG TO BRIEFLY SEVERE STORMS WILL ONCE AGAIN BE POSSIBLE FOR THE WESTERN TEXAS AND OKLAHOMA PANHANDLES. SATURDAY THROUGH EARLY NEXT WEEK...WILL SEE THE RIDGE AXIS BUILD BACK OVER THE PANHANDLES TO KEEP PRECIPITATION CHANCES LIMITED. && .FIRE WEATHER... NEITHER ELEVATED NOR FIRE WEATHER CONDITIONS ARE EXPECTED FOR THE NEXT 7 DAYS GIVEN THE RECENT WETTING RAINS. && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 15/14
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1249 PM CDT WED JUN 19 2013 .AVIATION... CONCERNS...ISOLATED THUNDERSTORMS POSSIBLE THIS AFTERNOON IN THE DFW METROPLEX AND WACO VICINITIES. A WARM FRONT THAT EXTENDED ALONG A LINE FROM 10 MILES NORTH OF KBKD /BRECKENRIDGE/ TO NEAR KACT /WACO/ TO 30 MILES NE OF KCLL /COLLEGE STATION/ WILL LIFT SLOWLY NORTHWARD THROUGH TONIGHT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THIS BOUNDARY THIS AFTERNOON AND THIS ACTIVITY IS EXPECTED TO DISSIPATE AS SUNSET APPROACHES. THE CHANCES AT THE INDIVIDUAL AIRPORTS IS LOW...SO HAVE JUST PLACED VCTS FOR THE 20Z TO 00Z PERIOD AT KACT /WACO/ AND LEFT OUT A MENTION OF VCTS IN THE METROPLEX TAFS FOR NOW. UPDATES FOR THE DFW METROPLEX TAFS MAY BE NEEDED LATER THIS AFTERNOON AS TOWERING CUMULUS IS ALREADY DEVELOPING. SOUTHEAST WINDS OF 5 TO 10 KNOTS THIS AFTERNOON AND EVENING WILL BECOME SOUTHERLY AT AROUND 15 KNOTS BY 16Z THURSDAY. 58 && .UPDATE... A WEAK...DIFFUSED FRONTAL BOUNDARY HAS LIFTED OVER THE WESTERN CWA AND NOW EXTENDS FROM NEAR BRECKENRIDGE SOUTHEAST TO SOUTH OF PALESTINE. EXPECT THIS BOUNDARY TO AID IN FOCUSING DEVELOPMENT THIS AFTERNOON ALONG AND NORTH OF THE FRONT. THE MCS OFF TO THE NORTHWEST HAD HELD TOGETHER FAIRLY WELL THIS MORNING...ESPECIALLY ON ITS SOUTHERN END. THE SYSTEM SHOULD BE ABLE TO MOVE INTO THE WESTERN CWA COUNTIES OF YOUNG AND STEPHENS AS EARLY AS 2 PM. ALTHOUGH OUR ATMOSPHERE IS UNSTABLE WITH GOOD MID LEVEL LAPSE RATES AND CAPE VALUES GENERALLY BETTER THAN 1800 J/KG...THE MCS WILL BE MOVING INTO AN ENVIRONMENT OF DECREASING BULK SHEAR WHICH WILL LIMIT THE POTENTIAL FOR ROTATING UPDRAFTS. CAPE VALUES ALONE SUGGEST SOME MARGINALLY SEVERE HAIL AND A POTENTIAL FOR 40-50 MPH DOWNBURST WINDS. 75 && .PREV DISCUSSION... /ISSUED 318 AM CDT WED JUN 19 2013/ THE ONLY MAJOR FORECASTING CHALLENGE WITH THIS PACKAGE WILL BE PATCHY FOG IN THE EASTERN ZONES THIS MORNING AND THUNDERSTORM CHANCES TODAY. LIGHT WIND AND DAMP GROUND ACROSS EAST TEXAS AND THE EASTERN PORTIONS OF NORTH TEXAS WILL RESULT IN PATCHY FOG THROUGH MID MORNING TODAY. IT APPEARS THAT MOST OF THE DENSE FOG SHOULD BE IN EAST TEXAS BUT A FEW NORTH TEXAS LOCATIONS MAY BRIEFLY FALL TO 1/2 MILE VISIBILITY. BY 11 AM...ANY FOG THAT DID DEVELOP WILL HAVE DISSIPATED. A COMPLEX OF STORMS...CURRENTLY ACROSS WESTERN OKLAHOMA AND THE PANHANDLE...WILL CONTINUE MOVING SOUTHEAST THROUGH THE EARLY MORNING HOURS. CLOUD TOPS IN THE SOUTHERN PORTION OF THE COMPLEX HAVE BEEN WARMING OVER THE PAST COUPLE OF HOURS AND THIS TREND WILL LIKELY CONTINUE. THE HRRR SEEMS TO HAVE THE MOST REASONABLE SOLUTION OF ALL MODELS BASED ON RADAR TRENDS OVER THE LAST FEW HOURS SO WILL FOLLOW IT FAIRLY CLOSELY. THEREFORE...EXPECT MOST OF THE WEST TEXAS ACTIVITY TO DISSIPATE BEFORE REACHING THE NORTHWEST ZONES AROUND MID MORNING...BUT WILL LEAVE 20 POPS IN TO ACCOUNT FOR ANY SHOWER OR STORM THAT MANAGES TO HOLD TOGETHER. BY THIS AFTERNOON...A FEW SHOWERS OR STORMS MAY DEVELOP ACROSS THE REGION AS TEMPERATURES WARM INTO THE 90S AND SOME LEFT OVER BOUNDARIES PROVIDE A FOCUS FOR LIFT. ANY STORMS THAT DO DEVELOP SHOULD BE DISORGANIZED PULSE STORMS DUE TO THE WEAK SHEARED AND WEAK FLOW ENVIRONMENT EXPECTED. ANY SHOWERS OR STORMS THAT DO DEVELOP THIS AFTERNOON WILL DISSIPATE WITH THE LOSS OF SURFACE HEATING AND INCREASING LARGE SCALE SUBSIDENCE FROM A BUILDING UPPER LEVEL RIDGE. THE UPPER RIDGE WILL BECOME THE DOMINANT WEATHER FEATURE ACROSS THE REGION THURSDAY THROUGH EARLY NEXT WEEK. THE GOOD NEWS IS THAT THE RIDGE WILL NEVER BECOME EXTREMELY STRONG AND AS A RESULT AFTERNOON HIGH TEMPERATURES SHOULD NOT BE TOO MUCH WARMER THAN SEASONAL NORMALS. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK GENERALLY IN THE LOWER AND MIDDLE 90S AND LOWS MOSTLY IN THE 70S. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 74 94 75 96 / 20 10 0 0 0 WACO, TX 94 72 94 73 95 / 20 10 0 0 0 PARIS, TX 89 70 92 71 94 / 20 10 5 0 5 DENTON, TX 92 71 94 72 96 / 20 10 0 0 0 MCKINNEY, TX 90 69 93 70 94 / 20 10 5 0 0 DALLAS, TX 93 75 94 76 95 / 20 10 0 0 0 TERRELL, TX 92 71 93 72 94 / 20 10 5 0 5 CORSICANA, TX 93 72 93 73 94 / 30 10 5 0 0 TEMPLE, TX 93 71 93 72 94 / 20 10 0 0 0 MINERAL WELLS, TX 93 70 94 71 96 / 30 5 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 58/75
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1116 AM CDT WED JUN 19 2013 .UPDATE... A WEAK...DIFFUSED FRONTAL BOUNDARY HAS LIFTED OVER THE WESTERN CWA AND NOW EXTENDS FROM NEAR BRECKENRIDGE SOUTHEAST TO SOUTH OF PALESTINE. EXPECT THIS BOUNDARY TO AID IN FOCUSING DEVELOPMENT THIS AFTERNOON ALONG AND NORTH OF THE FRONT. THE MCS OFF TO THE NORTHWEST HAD HELD TOGETHER FAIRLY WELL THIS MORNING...ESPECIALLY ON ITS SOUTHERN END. THE SYSTEM SHOULD BE ABLE TO MOVE INTO THE WESTERN CWA COUNTIES OF YOUNG AND STEPHENS AS EARLY AS 2 PM. ALTHOUGH OUR ATMOSPHERE IS UNSTABLE WITH GOOD MID LEVEL LAPSE RATES AND CAPE VALUES GENERALLY BETTER THAN 1800 J/KG...THE MCS WILL BE MOVING INTO AN ENVIRONMENT OF DECREASING BULK SHEAR WHICH WILL LIMIT THE POTENTIAL FOR ROTATING UPDRAFTS. CAPE VALUES ALONE SUGGEST SOME MARGINALLY SEVERE HAIL AND A POTENTIAL FOR 40-50 MPH DOWNBURST WINDS. 75 && .AVIATION... /12Z TAFS/ MVFR CONDS PREVAIL OVER A GOOD PORTION OF NORTH TEXAS WITH VIS GENERALLY AROUND 5SM. THERE ARE SOME AREAS OF DENSE FOG PRIMARILY IN THE LOWER VALLEYS BUT THIS SHOULD STAY OUT OF THE MAJOR AIRPORTS THROUGH MID MORNING. WILL PREVAIL VFR CONDS IN THE METROPLEX...ALTHOUGH AN AMD OR TWO MAY BE NEEDED IF VIS DROPS FURTHER THAN ANTICIPATED. A COMPLEX OF THUNDERSTORMS CONTINUES TO MOVE SOUTHEAST ACROSS WESTERN OKLAHOMA. THESE STORMS ARE LIKELY TO WEAKEN IN INTENSITY AS THEY APPROACH SO NO MENTION OF PRECIP IN THE CURRENT FORECAST. SOUTH WINDS AROUND 10KT EXPECTED THROUGH THE PERIOD. DUNN && .PREV DISCUSSION... /ISSUED 318 AM CDT WED JUN 19 2013/ THE ONLY MAJOR FORECASTING CHALLENGE WITH THIS PACKAGE WILL BE PATCHY FOG IN THE EASTERN ZONES THIS MORNING AND THUNDERSTORM CHANCES TODAY. LIGHT WIND AND DAMP GROUND ACROSS EAST TEXAS AND THE EASTERN PORTIONS OF NORTH TEXAS WILL RESULT IN PATCHY FOG THROUGH MID MORNING TODAY. IT APPEARS THAT MOST OF THE DENSE FOG SHOULD BE IN EAST TEXAS BUT A FEW NORTH TEXAS LOCATIONS MAY BRIEFLY FALL TO 1/2 MILE VISIBILITY. BY 11 AM...ANY FOG THAT DID DEVELOP WILL HAVE DISSIPATED. A COMPLEX OF STORMS...CURRENTLY ACROSS WESTERN OKLAHOMA AND THE PANHANDLE...WILL CONTINUE MOVING SOUTHEAST THROUGH THE EARLY MORNING HOURS. CLOUD TOPS IN THE SOUTHERN PORTION OF THE COMPLEX HAVE BEEN WARMING OVER THE PAST COUPLE OF HOURS AND THIS TREND WILL LIKELY CONTINUE. THE HRRR SEEMS TO HAVE THE MOST REASONABLE SOLUTION OF ALL MODELS BASED ON RADAR TRENDS OVER THE LAST FEW HOURS SO WILL FOLLOW IT FAIRLY CLOSELY. THEREFORE...EXPECT MOST OF THE WEST TEXAS ACTIVITY TO DISSIPATE BEFORE REACHING THE NORTHWEST ZONES AROUND MID MORNING...BUT WILL LEAVE 20 POPS IN TO ACCOUNT FOR ANY SHOWER OR STORM THAT MANAGES TO HOLD TOGETHER. BY THIS AFTERNOON...A FEW SHOWERS OR STORMS MAY DEVELOP ACROSS THE REGION AS TEMPERATURES WARM INTO THE 90S AND SOME LEFT OVER BOUNDARIES PROVIDE A FOCUS FOR LIFT. ANY STORMS THAT DO DEVELOP SHOULD BE DISORGANIZED PULSE STORMS DUE TO THE WEAK SHEARED AND WEAK FLOW ENVIRONMENT EXPECTED. ANY SHOWERS OR STORMS THAT DO DEVELOP THIS AFTERNOON WILL DISSIPATE WITH THE LOSS OF SURFACE HEATING AND INCREASING LARGE SCALE SUBSIDENCE FROM A BUILDING UPPER LEVEL RIDGE. THE UPPER RIDGE WILL BECOME THE DOMINANT WEATHER FEATURE ACROSS THE REGION THURSDAY THROUGH EARLY NEXT WEEK. THE GOOD NEWS IS THAT THE RIDGE WILL NEVER BECOME EXTREMELY STRONG AND AS A RESULT AFTERNOON HIGH TEMPERATURES SHOULD NOT BE TOO MUCH WARMER THAN SEASONAL NORMALS. EXPECT AFTERNOON HIGHS THROUGH EARLY NEXT WEEK GENERALLY IN THE LOWER AND MIDDLE 90S AND LOWS MOSTLY IN THE 70S. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 74 94 75 96 / 20 10 0 0 0 WACO, TX 94 72 94 73 95 / 20 10 0 0 0 PARIS, TX 91 70 92 71 94 / 20 10 5 0 5 DENTON, TX 93 71 94 72 96 / 20 10 0 0 0 MCKINNEY, TX 91 69 93 70 94 / 20 10 5 0 0 DALLAS, TX 93 75 94 76 95 / 20 10 0 0 0 TERRELL, TX 92 71 93 72 94 / 20 10 5 0 5 CORSICANA, TX 93 72 93 73 94 / 30 10 5 0 0 TEMPLE, TX 93 71 93 72 94 / 20 10 0 0 0 MINERAL WELLS, TX 93 70 94 71 96 / 30 5 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
356 PM MDT WED JUN 19 2013 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 230 PM MDT WED JUN 19 2013 FORECAST CHALLENGES THROUGH THE SHORT TERM DEAL WITH WINDS THROUGH FRIDAY. CURRENTLY...SOUTHWEST WINDS PRETTY STRONG OUT WEST OF THE LARAMIE RANGE THIS AFTERNOON. GETTING WIND GUSTS OVER 40 MPH IN CARBON COUNTY...EXTENDING TO THE WEST SLOPES OF THE LARAMIE RANGE. VERY DRY OUT THAT WAY...RAWLINS REPORTING 6 PERCENT HUMIDITY AT 1 PM THIS AFTERNOON...LARAMIE 9 PERCENT. LATEST SPC MESONALYSIS SHOWING A CAP STILL IN PLACE OUT IN THE PANHANDLE...WITH CONVECTIVE INHIBITION OF -25 TO -50 J/KG. VISIBLE IMAGERY SHOWING PRETTY MUCH CLEAR SKIES...WITH NO CU DEVELOPMENT ALL ALONG THE FRONT RANGE. THERE IS A SMALL WINDOW LATE THIS AFTERNOON WHERE THE SOUTHERN PANHANDLE SEES A BREAK IN THE CAP. WITH 700MB TEMPERATURES CLIMBING TO +16C...CONFIDENCE IS NOT HIGH THAT THE CAP WILL BE BROKEN. LATEST HRRR FORECAST DOES SHOW A FEW CELLS DEVELOPING ACROSS GOSHEN COUNTY AND THE NORTHERN PANHANDLE AFTER 00Z...SO WILL KEEP THE SLIGHT CHANCE POPS INHERITED GOING FOR A COUPLE HOURS THROUGH THE 03Z TIME FRAME. WINDS EASE THIS EVENING WITH THE GFS 700MB WINDS DECREASING TO 15-20KTS AFTER 06Z. FOR THURSDAY...WINDS TO REMAIN FAIRLY LIGHT OUT WEST THROUGH THE MORNING AND MID AFTERNOON. THEY DO START PICKING UP AFTER 00Z...INCREASING TO 25 TO 30KTS BY 06Z. LOOKS LIKE A PRETTY WINDY DAY ONCE AGAIN OUT WEST OF THE LARAMIE RANGE. FRIDAY WE START TO SEE A CHANGE AS THE UPPER LOW OVER WESTERN MONTANA OPENS UP AND A FAIRLY STRONG SHORTWAVE TRACKS INTO WESTERN WYOMING. 700MB WINDS OUT WEST TO REMAIN 25 TO 35 KTS...BUT WINDS OVER THE PANHANDLE TURN MORE EASTERLY AS THE LEE SIDE TROUGH DEEPENS. DEPENDING ON WHICH MODEL YOU LOOK AT...WE COULD SEE SHOWERS AND THUNDERSTORMS DEVELOPING OUT THAT WAY FRIDAY AFTERNOON. THE NEW ECMWF PAINTING A WIDESPREAD AREA OF QPF OVER THE NORTHERN PANHANDLE FRIDAY AFTERNOON AND EVENING. GFS IS DRY AND LATEST NAM/WRF SIMILAR TO THE ECMWF...THOUGH NOT AS WIDESPREAD ON PRECIP. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 345 PM MDT WED JUN 19 2013 PESKY PACIFIC NORTHWEST LOW PRESSURE WILL FINALLY BEGIN TO FILL THIS WEEKEND AS IT EJECTS INTO THE NRN PLAINS. AN ASSOCIATED SHORTWAVE WILL TRAVERSE THRU WYOMING ON SATURDAY. MEDIUM RANGE GUIDANCE VARIES SIGNIFICANTLY ON THE AMOUNT OF AVAILABLE LLVL MOISTURE ACROSS THE AREA ON SATURDAY. THE GFS IS SIGNIFICANTLY DRIER FOR MUCH OF THE CWA AS MUCH OF THE MOISTURE IS SHUNTED MOISTURE ACROSS EASTERN ZONES. MEANWHILE...THE ECMWF IS DEEPER AND FURTHER WEST WITH THE MOISTURE...WHICH WOULD BACK UP CONVECTION INTO THE EASTERN SOUTHEAST WYOMING PLAINS. FOR NOW HAVE KEPT AFTERNOON SHOWER AND THUNDERSTORM CHANCES GOING FOR MUCH OF THE EASTERN PLAINS. INSTABILITY PARAMETERS WOULD CERTAINLY BE SUPPORTIVE OF SEVERE WEATHER POTENTIAL IF THE LLVL MOISTURE MATERIALIZES. THIS WILL BE ESPECIALLY TRUE ACROSS THE WESTERN NEBRASKA PANHANDLE SATURDAY AFTERNOON AND EARLY EVENING. LLVL MOISTURE MAY HANG AROUND AGAIN ON SUNDAY AFTERNOON...AS PROGD INSTABILITIES REMAIN ELEVATED OUT ON THE EASTERN PLAINS. MAIN QUESTION WILL BE WHETHER OR NOT THERE WILL BE A FOCAL POINT TO PROVIDE LIFT. HOWEVER...RECENT MODEL GUIDANCE DOES SHOW AT THE ANOTHER WEAK SHORTWAVE PERHAPS LATE SUNDAY. FOR NOW HAVE ADDED SHOWER AND THUNDERSTORM CHANCES ALONG AND EAST OF THE LARAMIE RANGE DURING THE AFTERNOON...SPREADING INTO THE WESTERN NEBRASKA PANHANDLE BY EARLY EVENING. FLOW TURNS DRIER AND MORE SOUTHWESTERLY FOR MONDAY THROUGH WEDNESDAY. SO HAVE THE FIRST HALF OF NEXT WEEK DRY FOR NOW. FIRE WEATHER CONCERNS WILL BE HEIGHTENED GIVEN THIS TRANSITION TO DRY CONDITIONS. PROGD H7 TEMPERATURES WILL HOVER BETWEEN 13-15C THRU MUCH OF THE PERIOD...WHICH WILL YIELD AFTERNOON HIGHS GENERALLY IN THE 80S ACROSS SOUTHEAST WYOMING WITH 80S AND LOW/MID 90S ACROSS THE WESTERN NEBRASKA PANHANDLE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY MORNING) ISSUED AT 140 PM MDT WED JUN 19 2013 A WEAK DISTURBANCE WILL MOVE THROUGH THE REGION TODAY. A FEW ISOLATED -SHRA/-TSRA MAY DEVELOP IN THE VICINITY OF KCDR BETWEEN 22Z AND 02Z. ALL OTHER TERMINALS ARE EXPECTED TO REMAIN DRY. WINDY CONDITIONS WILL PREVAIL AT MOST SITES TODAY...WITH SOUTHEAST WINDS GUSTING TO 30 KTS AT THE PANHANDLE SITES AND SOUTHWEST WINDS GUSTING AS HIGH AS 40 KTS WEST OF THE LARAMIE RANGE. WINDS WILL EASE AND TURN TO THE WEST-NORTHWEST TONIGHT. && .FIRE WEATHER... ISSUED AT 230 PM PM MDT WED JUN 19 2013 SOUTHWEST WINDS OF 20 TO 30 MPH SUSTAINED WITH GUSTS TO 40 MPH WILL CONTINUE THIS AFTERNOON WEST OF THE LARAMIE RANGE. AFTERNOON HUMIDITIES HAVE ALREADY FALLEN INTO THE SINGLE DIGITS. WINDS ARE EXPECTED TO EASE BY MID EVENING. POOR HUMIDITY RECOVERIES EXPECTED OVERNIGHT WEST OF THE LARAMIE RANGE WITH GOOD RECOVERIES IN THE PANHANDLE. A DRY FORECAST THROUGH SATURDAY WITH WINDS INCREASING AGAIN FRIDAY AFTERNOON. THIS DUE TO A LOW PRESSURE SYSTEM TRACKING THROUGH MONTANA. THIS LOW WILL DRAG A COLD FRONT THROUGH THE AREA SATURDAY WITH SCATTERED CHANCES FOR SHOWERS AND THUNDERSTORMS IN THE PANHANDLE. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...CLAYCOMB LONG TERM...HAHN AVIATION...HAHN FIRE WEATHER...CLAYCOMB