Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/17/15


AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
954 PM CDT THU APR 16 2015 .UPDATE... JUST A QUICK UPDATE TO REFLECT CURRENT TEMPERATURE TRENDS AROUND THE STATE. CONTINUE TO SEE SHOWERS AND THUNDERSTORMS PUSH NORTH AND NORTHEAST INTO SOUTHWEST ARKANSAS. THESE SHOWERS AND THUNDERSTORMS ARE FORECAST TO WEAKEN AND LESSEN IN COVERAGE AS THEY ENTER THE CWA...HOWEVER DO EXPECT AT LEAST A FEW SHOWERS AND THUNDERSTORMS TO REMAIN. HRRR AND WRF DO SUPPORT THIS THINKING...AS A RESULT INCREASED POPS ACROSS SW AND CENTRAL ARKANSAS THROUGH THE OVERNIGHT HOURS. && .PREV DISCUSSION... /ISSUED 600 PM CDT THU APR 16 2015/ AVIATION... CLOUDS WILL INCREASE TONIGHT...AS AN UPPER LEVEL SYSTEM SWINGS THROUGH IN SOUTHWEST FLOW ALOFT. SYSTEM WILL BE ENOUGH TO TRIGGER SCATTERED SHOWERS/STORMS OVER THE SOUTHERN AND WESTERN PORTIONS OF THE AREA...AND AS SUCH...HAVE INCLUDED A MENTION IN THE HOT SPRINGS... PINE BLUFF...AND MONTICELLO FORECASTS. THROUGH THE NEXT 24 HOURS...MVFR CONDITIONS WILL PREVAIL BY EARLY FRIDAY MORNING...WITH TEMPORARY IFR VISBY AND CEILING RESTRICTIONS. CONDITIONS SHOULD IMPROVE BY 18Z...BUT STRATOCU CEILINGS WILL LIKELY REMAIN THROUGH THE END OF THE PERIOD. TAFS OUT SHORTLY. PREV DISCUSSION... /ISSUED ISSUED BY NATIONAL WEATHER SERVICE MEMPHIS TN/ DISCUSSION... UPPER LEVEL TROUGH WILL MOVE THROUGH THE REGION THIS WEEKEND BRINGING UNSETTLED WEATHER TO THE AREA. GENERALLY HUNG ON TO POPS INTO THE BEGINNING OF NEXT WEEK...THUS EXTENDING THE CHANCE OF PRECIPITATION INTO THE BEGINNING OF NEXT WEEK FOR PART OF THE AREA. SURFACE HIGH WILL BUILD INTO THE AREA AT THE BEGINNING OF THE WEEK AND SHOULD PROVIDE FOR SOME DRY WEATHER THROUGH MID-WEEK. THE NEXT FRONTAL SYSTEM BEGINS TO MOVE INTO THE REGION LATE WEDNESDAY INTO THURSDAY. EVEN WITH THE SURFACE HIGH AN UPPER LEVEL TOUGH WILL KEEP SOME CLOUDS IN THE REGION FOR MOST OF THE NEXT WEEK. TLSJR && .PRELIMINARY POINT TEMPS/POPS... BATESVILLE AR 59 78 61 73 / 10 30 30 70 CAMDEN AR 63 79 63 75 / 40 40 60 70 HARRISON AR 56 76 59 70 / 10 30 50 70 HOT SPRINGS AR 62 77 62 74 / 40 40 60 70 LITTLE ROCK AR 62 78 63 75 / 30 40 50 70 MONTICELLO AR 64 79 64 74 / 40 40 50 70 MOUNT IDA AR 61 76 61 73 / 40 40 60 70 MOUNTAIN HOME AR 57 77 59 71 / 10 20 40 70 NEWPORT AR 60 78 62 73 / 20 30 30 70 PINE BLUFF AR 63 78 64 74 / 40 40 50 70 RUSSELLVILLE AR 60 78 62 74 / 20 40 60 70 SEARCY AR 60 78 62 73 / 20 30 40 70 STUTTGART AR 63 78 64 74 / 30 40 40 70 && .LZK WATCHES/WARNINGS/ADVISORIES...NONE. && $$ 65
AREA FORECAST DISCUSSION
NWS PUEBLO CO
933 PM MDT THU APR 16 2015 .UPDATE... ISSUED AT 930 PM MDT THU APR 16 2015 UPDATED TO MAKE SOME MINOR ADJUSTMENTS TO POPS THROUGH TOMORROW BASED ON RADAR TRENDS AND 00Z GUIDANCE. LOOKS LIKE THE SVR THREAT IS OVER FOR NOW...BUT COULD STILL SEE SOME ISOLD TS OVER THE SE PLAINS TONIGHT. STILL EXPECTING SOME DRY AIR TO PUSH INTO SE CO TOMORROW...BUT THERE WILL BE SCT SHOWERS AROUND IN THE MORNING. MAIN AREA TO WATCH THROUGH TOMORROW WILL BE THE UPPER ARKANSAS AND GUNNISON VALLEY...WHERE SOME GUIDANCE IS SHOWING A PERSISTENT SNOW BAND DEVELOPING. ROSE UPDATE ISSUED AT 543 PM MDT THU APR 16 2015 UPDATED THE FORECAST TO INCLUDE TELLER COUNTY AND NORTHERN FREMONT COUNTY IN A WINTER STORM WARNING. MULTIPLE BANDS OF PRECIP EXPECTED TO ROTATE IN FROM THE SE TONIGHT...WITH VARIOUS MODELS SHOWING .7 TO 1.4 INCHES OF QPF. WITH COOLING TEMPS AFTER SUNSET EXPECT ROADS TO ICE OVER...LEADING TO HAZARDOUS TRAVEL IN THE WARNED AREAS. ROSE UPDATE ISSUED AT 423 PM MDT THU APR 16 2015 UPDATED THE FORECAST TO CANCEL THE RED FLAG FOR THE SAN LUIS VALLEY. SCATTERED SHOWERS ARE OVER THE VALLEY AND HUMIDITY IS NO LONGER CRITICAL. ROSE && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 356 PM MDT THU APR 16 2015 ...MODERATE TO HEAVY SNOW POSSIBLE FOR THE MOUNTAINS TONIGHT AND FRIDAY... ...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE FOR THE FAR SOUTHEAST PLAINS AGAIN ON FRIDAY THOUGH THIS IS DEPENDENT ON HOW MUCH RAIN FALLS OVER THESE AREAS TONIGHT... ...MARGINAL POTENTIAL FOR SEVERE POSSIBLE FOR NORTHERN EL PASO AND KIOWA COUNTIES ON FRIDAY... STILL A HIGHLY DYNAMIC FORECAST AS MODELS HONE IN ON TRACK AND STRENGTH OF THE CLOSED LOW CURRENTLY ACROSS THE 4 CORNERS REGION. MODELS BOBBLE THE UPPER LOW SOUTHWARD A BIT THIS EVENING...THEN BACK TO THE NORTHEAST ACROSS THE CO/NM BORDER TONIGHT AS ENERGY ROTATES AROUND THE BASE OF THE UPPER LOW AND ACROSS CO. THEN IT MAKES STEADIER PROGRESS TO THE NORTHEAST INTO EAST CENTRAL CO ON FRIDAY. ALREADY SEEING ENHANCEMENT ACROSS THE SOUTHEAST MTS AND NRN NM AS THE NEXT IMPULSE APPROACHES. HRRR SEEMS TO HAVE PICKED UP ON THIS TREND FAIRLY WELL. WE SHOULD CONTINUE TO SEE SHOWERS FILL IN ACROSS THE SOUTHEAST MOUNTAINS...AND I-25 CORRIDOR...WITH SNOW LEVELS AROUND 6000-6500 FEET. SNOW LEVELS MAY ACTUALLY RISE A BIT FOR THE LOWER EASTERN SLOPES AS STRONG WAA OCCURS OVERNIGHT...WHICH COULD CAUSE A SWITCH BACK TO RAIN AT KCOS OVERNIGHT. HOWEVER...MTN AREAS SHOULD CONTINUE TO SEE SNOW AND HAVE EXPANDED ADVISORIES ACROSS MUCH OF THE MOUNTAIN AREAS. GIVEN THE CONVECTIVE POTENTIAL WITH THIS EVENINGS ROUND...CONCERNED THAT PORTIONS OF TELLER COUNTY COULD HIT WARNING CRITERIA...THOUGH DON`T THINK IT WILL BE WIDESPREAD ENOUGH ACROSS THE ZONE TO WARRANT AN UPGRADE. CENTRAL LAKE COUNTY COULD BE IN A SIMILAR BOAT...SO THESE AREAS WILL BE THE ONES TO WATCH CLOSELY. MEANWHILE...MODELS SHOW DEFORMATION BAND SNOW SPREADING WESTWARD INTO THE SOUTHWEST MOUNTAINS TONIGHT AND CONTINUING THROUGH FRIDAY. HAVE OPTED TO EXPAND ADVISORIES INTO THE LA GARITAS WHERE SNOW AMOUNTS ARE APPROACHING THE 6-12 INCH RANGE. STILL SOME QUESTION OVER THE EASTERN SAN JUANS THOUGH...COULD SEE A COUPLE INCHES FALL THERE TONIGHT...WITH ANOTHER 1-3 INCHES FALLING ON FRIDAY AS THE UPPER LOW WRAPS DEFORMATION BAND BACK TO THE SOUTHWEST ACROSS THE REGION. CONTEMPLATED AN ADVISORY FOR THIS REGION...BUT AM COMING UP SHY OF THE 6-12 INCHES NEEDED FOR A WINTER WX ADVISORY...THOUGH CERTAINLY SUBTLE CHANGES IN THE TRACK AND STRENGTH OF THE LOW COULD RESULT IN HEAVIER AMOUNTS FOR THIS REGION. STICKING TRUE TO THE GRIDS FOR NOW AND WILL LET LATER SHIFTS REASSESS. AS FOR SEVERE THUNDERSTORM POTENTIAL ACROSS THE PLAINS...APPEARS TIMING OF THE INITIAL WAVE THIS AFTERNOON WAS TOO QUICK FOR THE LOW LEVEL MOISTURE RETURN...AND NICE LINE OF THUNDERSTORMS HAS ALREADY DEVELOPED AND PUSHED EASTWARD INTO KANSAS. HOWEVER AS SURFACE WINDS HAVE VEERED MORE EASTERLY DUE TO FALLING SFC PRESSURES ACROSS NEW MEXICO...40S AND LOWER 50 DEW POINTS HAVE PULLED WESTWARD INTO THE FAR SOUTHEAST PLAINS. ACTIVITY INCREASING ACROSS NORTHERN NEW MEXICO MAY STILL HAVE A CHANCE TO INTERACT WITH THIS MOISTURE TO PRODUCE SOME ISOLATED SEVERE THUNDERSTORMS...WITH HAIL AND GUSTY WINDS THE PRIMARY STORM THREATS. OVERNIGHT...LATEST HRRR HINTS AT ANOTHER ROUND CLIPPING BY BACA COUNTY DURING THE 8Z TO 09Z TIMEFRAME...AND EVEN SOME SPOTTY THUNDERSTORMS POSSIBLE AS FAR WEST AS THE I-25 CORRIDOR. SO THOUGH MAIN THREAT FOR SEVERE THUNDERSTORMS WILL BE THIS EVENING...CAN`T RULE OUT A LOW GRADE SEVERE THREAT ACROSS THE FAR SOUTHEAST PLAINS EVEN DURING THE OVERNIGHT HOURS...THOUGH THUNDERSTORMS WILL TEND TO BE MORE ELEVATED. TOMORROW AS THE SURFACE LOW LIFTS INTO SOUTHEAST CO...COULD SEE SOME ISOLATED THUNDERSTORMS EVEN IN THE MORNING...AND LAPSE RATES WILL BE STEEP GIVEN THE MID LEVEL COOLING ASSOCIATED WITH THE SURFACE LOW. NAM12 SHOWS UP TO 1000 J/KG OF CAPE ACROSS NORTHERN PORTIONS OF THE SE PLAINS DURING THE MORNING...SO COULD HAVE ANOTHER CHANCE FOR SEVERE THUNDERSTORMS ON FRIDAY. BY AFTERNOON...DRY AIR SPREADS INTO THE SOUTHEAST PLAINS AS SURFACE LOW LIFTS NORTHWARD. THIS PUTS THE AXIS OF BEST INSTABILITY ALONG THE NORTHERN FRINGES OF THE SOUTHEAST PLAINS BY AFTERNOON...PRIMARILY NORTHEAST EL PASO AND KIOWA COUNTIES. THESE AREAS ARE OUTLOOKED FOR A MARGINAL SEVERE THREAT TOMORROW...AND THIS LOOKS ON TARGET. COULD SEE THIS MARGINAL THREAT SLIPPING SOUTHWARD A BIT TO ACCOUNT FOR ANY STRONG MORNING CONVECTION. BUT AS DRY AIR EXPANDS NORTHWARD...SO DOES THE POTENTIAL FOR CRITICAL FIRE WEATHER PARAMETERS...ESPECIALLY ACROSS LAS ANIMAS...BACA...BENT...PROWERS... AND OTERO COUNTIES. THE MITIGATING FACTOR WILL BE THE POTENTIAL FOR RAINFALL TO WET FUELS TONIGHT OVER THESE SAME ZONES. GIVEN THIS POTENTIAL...HAVE NOT GONE OUT WITH A FIRE WEATHER WATCH...BUT IF PRECIPITATION DOESN`T MATERIALIZE ACROSS A WIDESPREAD ENOUGH AREA ACROSS THESE REGION...THEN LATER SHIFTS MAY NEED TO HOIST A RED FLAG WARNING. -KT .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 356 PM MDT THU APR 16 2015 FRIDAY NIGHT THROUGH SATURDAY...MODELS HAVE SHIFTED A BIT OVER THE PST 24 HRS...BUT STILL REMAIN FAIRLY CONSISTENT WITH THE PLACEMENT AND PATH OF THE UPPER LOW. FRIDAY NIGHT THE LOW PRESSURE SYSTEM IS FORECAST TO BE CENTERED RIGHT OVER COLORADO...THEN OVER THE NEXT 24 HRS IT WILL WOBBLE A BIT BEFORE SLOWLY EXITING THE STATE VIA THE EASTERN BORDER. THIS PATTERN WOULD IMPLY THAT THE MTS...ESPECIALLY THE CONTDVD...WILL GET THE BRUNT OF SNOWFALL...MAINLY THROUGH FRIDAY NIGHT. THEREFORE...ONGOING WINTER HIGHLIGHTS RUNNING THROUGH 12Z SATURDAY LOOK REASONABLE. SNOW AMOUNTS WILL THEN TAPER OVER OVER THE DAY SATURDAY AS TEMPS BEGIN TO WARM AND THE SYSTEM WEAKENS. ISOLATED TO SCATTERED SHOWERS ARE FORECAST FOR THE REMAINDER OF THE LOWER ELEVATIONS...AND TEMPS DO NOT LOOK PARTICULARLY COLD WITH MIN TEMPS IN THE 30S TO AROUND 40 F FOR THE PLAINS...AND MAX TEMPS SATURDAY IN THE MID 50S TO LOWER 60S. SUNDAY AND MONDAY...THE UPPER SYSTEM WEAKENS AND EXITS TO THE EAST LATE SATURDAY...WITH BRISK NW FLOW ALOFT THEN SETTLING IN ACROSS THE STATE. A COUPLE OF UPPER SHORTWAVES ARE EXPECTED TO DROP DOWN ACROSS THE STATE ON BOTH DAYS...KEEPING THE THREAT OF SHOWER ACTIVITY FOR THE CWA IN PLACE. LOOK FOR SCATTERED SHOWERS OVER THE HIGHER TERRAIN...AND ISOLATED SHOWERS FOR THE PLAINS...WITH MAX TEMPS BOTH DAYS HOVERING IN THE 50S TO NEAR 60 F. TUESDAY THROUGH THURSDAY...CONFIDENCE IS FAIRLY LOW FOR WHAT HAPPENS BEYOND MONDAY...THOUGH LONG RANGE MODELS SEEM TO AGREE ON THE QUESTION MARK. A TEMPORARY RIDGE BUILDS INTO THE DESERT SW STARTING TUE...HELPING TO LOWERING PCPN CHANCES AS WELL AS BOOSTING MAX TEMPS FOR THE PLAINS BACK INTO THE 70S. TWO SEPARATE UPPER CLOSED LOW SYSTEMS APPROACH STARTING WED NIGHT...ONE OVER THE PAC NW AND THE OTHER OVER S CA...BUT THIS PATTERN WILL MOST LIKELY GO THROUGH MULTIPLE ADJUSTMENTS BEFORE THEN. MOORE && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 356 PM MDT THU APR 16 2015 CURRENTLY...VFR TO MVFR CONDITIONS FOR THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS AS WELL AS FOR MUCH OF THE LOWER ELEVATIONS. FOR ELEVATIONS ABOVE ROUGHLY 7000 FT...IFR CONDITIONS PREVAILED DUE TO EXTENSIVE LOWER CLOUD COVER AND ONGOING SNOW SHOWERS. THE UPPER LOW WILL SLOWLY MOVE FROM THE SW QUAD TO THE CENTRAL PORTIONS OF THE STATE OVER THE NEXT 24 HRS...BRINGING WAVES OF RAIN/SNOW SHOWERS TO THE LOWER ELEVATIONS AND SNOW...HEAVY AT TIMES...TO THE MTS. EXPECT MVFR CONDITIONS FOR KPUB AND KALS OVER THE NEXT 24 HRS. KCOS IS EXPECTED TO DIP INTO IFR CONDITIONS THIS EVENING...THEN BRIEFLY DROP DOWN INTO LIFR AFTER 11Z TOMORROW MORN. CONDITIONS ACROSS THE HIGHER TERRAIN AND MT PASSES WILL REMAIN IFR TO LIFR. MOORE && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ059-062- 063-074-075. WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ077>079-084. WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058-060-061- 072-073-080-082. WINTER STORM WARNING UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR COZ076- 081. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR COZ066. && $$ UPDATE...ROSE SHORT TERM...KT LONG TERM...MOORE AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
812 PM MDT THU APR 16 2015 .UPDATE... ISSUED AT 812 PM MDT THU APR 16 2015 A BIT OF AN INVERTED TROUGH ALONG THE FRONT RANGE URBAN CORRIDOR IS KEEPING WINDS NORTHWEST AND SLIGHTLY WARMER TEMPERATURES...KEEPING AREAS RIGHT UP AGAINST THE FOOTHILLS WARMER AND MOSTLY RAIN OR A RAIN/SNOW MIX. FURTHER EAST ALONG AND EAST OF I25...COLDER AIR AND A SHORTWAVE HAS CHANGED PRECIP OVER TO SNOW...ALBEIT A VERY WET SNOW. THIS SNOW WILL ACCUMULATE MORE ON GRASS...TREES AND ANYTHING ELSE OFF THE GROUND RATHER THAN STREETS. STREETS WILL MAINLY CONTINUE TO BE SLUSHY AND WET EXCEPT FOR UNDER THE HEAVIER BAND WHERE AN INCH OR SO OF SNOW MAY ACCUMULATE WITHIN HALF AN HOUR...AS WELL AS ON THE HIGHER TERRAIN OF THE PALMER DIVIDE. MORE UNSTABLE AIR IS PUSHING NORTH FROM SOUTHEASTERN COLORADO FOR A BETTER CHANCE OF THUNDERSTORMS TONIGHT...MAINLY EAST OF A STERLING TO LIMON LINE. THE MAIN MOISTURE PUSH IS STILL EXPECTED TO BEGIN AROUND MIDNIGHT FROM THE SOUTH....MOVING NORTH AND INCREASING SNOW ACROSS THE HIGH TERRAIN...WHILE DOWN BELOW WARMER TEMPERATURES ADVECTING IN WILL LIKELY KEEP MOST OF THE PLAINS WITH RAIN...WITH SOME MIX OF RAIN AND SNOW BETWEEN 5000 AND 6000. NOT A LOT OF CHANGES NEEDED TO BE DONE TO THE ONGOING FORECAST. SNOW ACROSS THE MOUNTAINS...MAINLY ALONG AND EAST OF THE DIVIDE...WILL CONTINUE THIS EVENING AND INCREASE SNOWFALL RATES AFTER MIDNIGHT. SOME AREAS COULD SEE AN INCH TO TWO INCHES PER HOUR IN ACCUMULATION RATES. ROADS WILL BE SNOW PACKED AND DIFFICULT TO TRAVEL ON. HEAVIEST EXPECTED AMOUNTS REMAIN EXPECTED OVER THE HIGH TERRAIN OF BOULDER AND LARIMER COUNTIES. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 257 PM MDT THU APR 16 2015 WATER VAPOR SATELLITE IMAGERY SHOWING THE UPPER LEVEL LOW CENTERED OVER THE FOUR CORNERS AT THIS TIME WITH A SHORT WAVE ROTATING AROUND IT OVER NORTH CENTRAL NEW MEXICO. THIS WAVE WILL ROTATE NORTH OVER EASTERN COLORADO TONIGHT BRINGING WIDESPREAD RAIN AND SNOW TO THE AREA. IN ADDITION TO THE WAVE PASSING ACROSS THE AREA...UPSLOPE WINDS WILL REMAIN STRONG AT 20 TO 40 KNOTS ALONG THE FRONT RANGE. EXPECT MODERATE TO HEAVY SNOW THROUGH THE NIGHT WITH SNOWFALL RATES 1 TO 2 INCHES PER HOUR AT TIMES IN THE FOOTHILLS AND MOUNTAINS. LAPSE RATES ARE ALSO STEEP...SO A FEW THUNDERSTORMS WILL BE POSSIBLE TONIGHT. WILL MENTION A SLIGHT CHANCE IN THE FORECAST FOR THE FRONT RANGE AND EASTERN PLAINS TONIGHT AND FRIDAY. MODELS GENERALLY SHOWING 1 TO 2 INCHES OF PRECIPITATION THROUGH FRIDAY MORNING WITH THIS SYSTEM...A LITTLE MORE OVER LARIMER COUNTY. SO 1 TO 3 FEET LOOKS ON TRACK FOR SNOWFALL AMOUNTS IN THE FOOTHILLS AND FRONT RANGE MOUNTAINS. EXPECT A RAIN/SNOW MIX THIS EVENING BETWEEN 5000 TO 6000 FEET WITH OCCASIONAL HEAVY SNOW UNDER THE STRONGEST SHOWERS. EASTERLY WINDS AROUND THE LOW WILL CONTINUE TO PUMP MOISTURE INTO THE AREA ALONG WITH WARMER AIR. THIS IS EXPECTED TO CHANGE SNOW TO RAIN ACROSS THE DENVER AREA OVERNIGHT. BY FRIDAY MORNING...EXPECT RAIN FOR MOST PLACES UNDER 6000 FEET. MAY SEE UP TO 6 INCHES OF SLUSHY SNOW PRIOR TO CHANGING TO RAIN IN THE DENVER AREA OVERNIGHT...POSSIBLY A LITTLE MORE NEAR THE FOOTHILLS AND PALMER DIVIDE. WILL ISSUE AN ADVISORY FOR PARK COUNTY AND PALMER DIVIDE WHERE AN ADDITIONAL 4 TO 8 INCHES WILL BE POSSIBLE. ON FRIDAY...THE UPPER LEVEL LOW WILL LIFT INTO COLORADO. AT THE SURFACE...A LOW WILL MOVE EAST ACROSS EASTERN COLORADO. TO THE NORTH AND EAST OF THE SURFACE LOW...SURFACE BASED CAPES CLIMB TO AROUND 2000 J/KG BASED ON THE 18Z NAM. WITH STRONG SHEAR IN PLACE...THIS WILL BE ENOUGH INSTABILITY FOR A CHANCE OF SEVERE THUNDERSTORMS...MAIN THREATS WILL BE LARGE HAIL UP TO GOLF BALL SIZE AND TORNADOS. RIGHT NOW APPEARS THE BEST CHANCE WILL BE FROM GREELEY TO LIMON AND EASTWARD...THOUGH THIS WILL DEPEND ON WHERE THE LOW TRACKS. FOR THE FOOTHILLS AND MOUNTAINS...STILL LOOKS LIKE IT WILL STAY COLD ENOUGH FOR SNOW THROUGH THE DAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 257 PM MDT THU APR 16 2015 THE FIRST PART OF THE LONG TERM FORECAST HINGES OF THE LOCATION AND MOVEMENT OF THE 500 MB UPPER LEVEL LOW PRESSURE SYSTEM. THE MODELS ARE IN PRETTY GOOD AGREEMENT...HOWEVER JUST A SLIGHT DEVIATION IN THE UPPER LOW TRACK WOULD AFFECT PRECIPITATION AND SNOWFALL AMOUNTS ACROSS NORTH CENTRAL AND NORTHEASTERN COLORADO. THE ECMWF HAS BEEN VERY CONSISTENT AND HAS THE 500 MB LOW CENTERED JUST WEST OF COLORADO SPRINGS AT 00Z SATURDAY. THE GFS AND NAM MODELS HAVE THE CENTER NEAR CANON CITY WHICH IS APPROXIMATELY 75 SOUTH OF THE PREVIOUS TWO RUNS. THESE MODELS THEN TRACK THE LOW TO NEAR DENVER BY 12Z SATURDAY MORNING. AS THE LOW MOVES NORTH DENVER SHOULD SEE A DECREASE IN PRECIPITATION...HOWEVER THE MOUNTAINS AND FOOTHILLS NEAR THE WYOMING BORDER COULD STILL BE UNDER THE GUN AS WRAP AROUND PRECIP WRAPS INTO THE REGION FROM THE NORTH. THE 15Z RUC JUST CAME IN AND SHOWS THE UPPER LOW TAKING A MORE SOUTHERLY TRACK ACROSS SOUTHERN COLORADO. THIS TRACK COULD PROLONG THE PRECIP EVENT BUT FOR NOW WILL GO WITH THE CONSENSUS OF THE GFS...ECMWF AND NAM. PRECIPITATION CHANCES DECREASE SATURDAY NIGHT INTO SUNDAY AS THE UPPER LOW WEAKENS AND MOVES INTO THE CENTRAL PLAINS STATES AND A NORTHWEST FLOW ALOFT DEVELOPS OVER THE STATE. UNSETTLED WEATHER WILL CONTINUE ACROSS NORTH CENTRAL AND NORTHEASTERN COLORADO THROUGH MONDAY AS RESIDUAL MOISTURE COMBINES WITH INSTABILITY DUE TO DAYTIME HEATING. A WEAK SURGE IN THE NORTHWEST FLOW COULD ENHANCE PRECIPITATION CHANCES. WARMER AND DRIER WEATHER WILL RETURN TO THE REGION ON TUESDAY AS UPPER LEVEL HIGH PRESSURE BUILDS OVER THE ROCKY MOUNTAIN REGION. && .AVIATION...(FOR THE TAFS THROUGH 06Z FRIDAY EVENING) ISSUED AT 812 PM MDT THU APR 16 2015 CURRENT HEAVIER SNOW AT KAPA AND KDEN SHOULD CONTINUE FOR THE NEXT COUPLE HOURS...BEFORE A BRIEF BREAK. ADDITIONAL MOISTURE BUT WARMER TEMPERATURES ARE THEN EXPECTED TO PUSH IN AFTER MIDNIGHT AND EVENTUALLY TURN PRECIP TO RAIN BY FRIDAY MORNING...ESPECIALLY AT KDEN...WHERE KAPA AND KBJC COULD CONTINUE SEEING RAIN SNOW MIX. VISIBILITY WILL FALL TO A QUARTER MILE AT TIMES IN THE HEAVIER SNOW. CEILINGS WILL BE UNDER 1000 FEET THROUGH MID FRIDAY MORNING BEFORE RAISING SLIGHTLY. NORTHERLY WINDS WILL PREVAIL AT SPEEDS LESS THAN 20 KNOTS. SNOW ACCUMULATION AT KDEN IS EXPECTED TO STAY BELOW 3 INCHES...WITH UP TO 6 INCHES POSSIBLE AT KAPA AND KBJC. ISOLATED THUNDERSTORMS ARE EXPECTED TO FORM TONIGHT...BUT AT THIS TIME THEY ARE EXPECTED TO STAY EAST OF THE AIRPORTS. CONVECTION IS EXPECTED AGAIN FRIDAY AFTERNOON WHERE THE AIRPORTS MAY HAVE A BETTER CHANCE OF SEEING SOME THUNDERSTORMS...BUT MOST OF THE ACTIVE WEATHER WILL REMAIN OUT ON THE EASTERN PLAINS. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ037-041. WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ033>036. && $$ UPDATE...KRIEDERMAN SHORT TERM...MEIER LONG TERM...JK AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
546 PM MDT THU APR 16 2015 .UPDATE... ISSUED AT 543 PM MDT THU APR 16 2015 UPDATED THE FORECAST TO INCLUDE TELLER COUNTY AND NORTHERN FREMONT COUNTY IN A WINTER STORM WARNING. MULTIPLE BANDS OF PRECIP EXPECTED TO ROTATE IN FROM THE SE TONIGHT...WITH VARIOUS MODELS SHOWING .7 TO 1.4 INCHES OF QPF. WITH COOLING TEMPS AFTER SUNSET EXPECT ROADS TO ICE OVER...LEADING TO HAZARDOUS TRAVEL IN THE WARNED AREAS. ROSE UPDATE ISSUED AT 423 PM MDT THU APR 16 2015 UPDATED THE FORECAST TO CANCEL THE RED FLAG FOR THE SAN LUIS VALLEY. SCATTERED SHOWERS ARE OVER THE VALLEY AND HUMIDITY IS NO LONGER CRITICAL. ROSE && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 356 PM MDT THU APR 16 2015 ...MODERATE TO HEAVY SNOW POSSIBLE FOR THE MOUNTAINS TONIGHT AND FRIDAY... ...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE FOR THE FAR SOUTHEAST PLAINS AGAIN ON FRIDAY THOUGH THIS IS DEPENDENT ON HOW MUCH RAIN FALLS OVER THESE AREAS TONIGHT... ...MARGINAL POTENTIAL FOR SEVERE POSSIBLE FOR NORTHERN EL PASO AND KIOWA COUNTIES ON FRIDAY... STILL A HIGHLY DYNAMIC FORECAST AS MODELS HONE IN ON TRACK AND STRENGTH OF THE CLOSED LOW CURRENTLY ACROSS THE 4 CORNERS REGION. MODELS BOBBLE THE UPPER LOW SOUTHWARD A BIT THIS EVENING...THEN BACK TO THE NORTHEAST ACROSS THE CO/NM BORDER TONIGHT AS ENERGY ROTATES AROUND THE BASE OF THE UPPER LOW AND ACROSS CO. THEN IT MAKES STEADIER PROGRESS TO THE NORTHEAST INTO EAST CENTRAL CO ON FRIDAY. ALREADY SEEING ENHANCEMENT ACROSS THE SOUTHEAST MTS AND NRN NM AS THE NEXT IMPULSE APPROACHES. HRRR SEEMS TO HAVE PICKED UP ON THIS TREND FAIRLY WELL. WE SHOULD CONTINUE TO SEE SHOWERS FILL IN ACROSS THE SOUTHEAST MOUNTAINS...AND I-25 CORRIDOR...WITH SNOW LEVELS AROUND 6000-6500 FEET. SNOW LEVELS MAY ACTUALLY RISE A BIT FOR THE LOWER EASTERN SLOPES AS STRONG WAA OCCURS OVERNIGHT...WHICH COULD CAUSE A SWITCH BACK TO RAIN AT KCOS OVERNIGHT. HOWEVER...MTN AREAS SHOULD CONTINUE TO SEE SNOW AND HAVE EXPANDED ADVISORIES ACROSS MUCH OF THE MOUNTAIN AREAS. GIVEN THE CONVECTIVE POTENTIAL WITH THIS EVENINGS ROUND...CONCERNED THAT PORTIONS OF TELLER COUNTY COULD HIT WARNING CRITERIA...THOUGH DON`T THINK IT WILL BE WIDESPREAD ENOUGH ACROSS THE ZONE TO WARRANT AN UPGRADE. CENTRAL LAKE COUNTY COULD BE IN A SIMILAR BOAT...SO THESE AREAS WILL BE THE ONES TO WATCH CLOSELY. MEANWHILE...MODELS SHOW DEFORMATION BAND SNOW SPREADING WESTWARD INTO THE SOUTHWEST MOUNTAINS TONIGHT AND CONTINUING THROUGH FRIDAY. HAVE OPTED TO EXPAND ADVISORIES INTO THE LA GARITAS WHERE SNOW AMOUNTS ARE APPROACHING THE 6-12 INCH RANGE. STILL SOME QUESTION OVER THE EASTERN SAN JUANS THOUGH...COULD SEE A COUPLE INCHES FALL THERE TONIGHT...WITH ANOTHER 1-3 INCHES FALLING ON FRIDAY AS THE UPPER LOW WRAPS DEFORMATION BAND BACK TO THE SOUTHWEST ACROSS THE REGION. CONTEMPLATED AN ADVISORY FOR THIS REGION...BUT AM COMING UP SHY OF THE 6-12 INCHES NEEDED FOR A WINTER WX ADVISORY...THOUGH CERTAINLY SUBTLE CHANGES IN THE TRACK AND STRENGTH OF THE LOW COULD RESULT IN HEAVIER AMOUNTS FOR THIS REGION. STICKING TRUE TO THE GRIDS FOR NOW AND WILL LET LATER SHIFTS REASSESS. AS FOR SEVERE THUNDERSTORM POTENTIAL ACROSS THE PLAINS...APPEARS TIMING OF THE INITIAL WAVE THIS AFTERNOON WAS TOO QUICK FOR THE LOW LEVEL MOISTURE RETURN...AND NICE LINE OF THUNDERSTORMS HAS ALREADY DEVELOPED AND PUSHED EASTWARD INTO KANSAS. HOWEVER AS SURFACE WINDS HAVE VEERED MORE EASTERLY DUE TO FALLING SFC PRESSURES ACROSS NEW MEXICO...40S AND LOWER 50 DEW POINTS HAVE PULLED WESTWARD INTO THE FAR SOUTHEAST PLAINS. ACTIVITY INCREASING ACROSS NORTHERN NEW MEXICO MAY STILL HAVE A CHANCE TO INTERACT WITH THIS MOISTURE TO PRODUCE SOME ISOLATED SEVERE THUNDERSTORMS...WITH HAIL AND GUSTY WINDS THE PRIMARY STORM THREATS. OVERNIGHT...LATEST HRRR HINTS AT ANOTHER ROUND CLIPPING BY BACA COUNTY DURING THE 8Z TO 09Z TIMEFRAME...AND EVEN SOME SPOTTY THUNDERSTORMS POSSIBLE AS FAR WEST AS THE I-25 CORRIDOR. SO THOUGH MAIN THREAT FOR SEVERE THUNDERSTORMS WILL BE THIS EVENING...CAN`T RULE OUT A LOW GRADE SEVERE THREAT ACROSS THE FAR SOUTHEAST PLAINS EVEN DURING THE OVERNIGHT HOURS...THOUGH THUNDERSTORMS WILL TEND TO BE MORE ELEVATED. TOMORROW AS THE SURFACE LOW LIFTS INTO SOUTHEAST CO...COULD SEE SOME ISOLATED THUNDERSTORMS EVEN IN THE MORNING...AND LAPSE RATES WILL BE STEEP GIVEN THE MID LEVEL COOLING ASSOCIATED WITH THE SURFACE LOW. NAM12 SHOWS UP TO 1000 J/KG OF CAPE ACROSS NORTHERN PORTIONS OF THE SE PLAINS DURING THE MORNING...SO COULD HAVE ANOTHER CHANCE FOR SEVERE THUNDERSTORMS ON FRIDAY. BY AFTERNOON...DRY AIR SPREADS INTO THE SOUTHEAST PLAINS AS SURFACE LOW LIFTS NORTHWARD. THIS PUTS THE AXIS OF BEST INSTABILITY ALONG THE NORTHERN FRINGES OF THE SOUTHEAST PLAINS BY AFTERNOON...PRIMARILY NORTHEAST EL PASO AND KIOWA COUNTIES. THESE AREAS ARE OUTLOOKED FOR A MARGINAL SEVERE THREAT TOMORROW...AND THIS LOOKS ON TARGET. COULD SEE THIS MARGINAL THREAT SLIPPING SOUTHWARD A BIT TO ACCOUNT FOR ANY STRONG MORNING CONVECTION. BUT AS DRY AIR EXPANDS NORTHWARD...SO DOES THE POTENTIAL FOR CRITICAL FIRE WEATHER PARAMETERS...ESPECIALLY ACROSS LAS ANIMAS...BACA...BENT...PROWERS... AND OTERO COUNTIES. THE MITIGATING FACTOR WILL BE THE POTENTIAL FOR RAINFALL TO WET FUELS TONIGHT OVER THESE SAME ZONES. GIVEN THIS POTENTIAL...HAVE NOT GONE OUT WITH A FIRE WEATHER WATCH...BUT IF PRECIPITATION DOESN`T MATERIALIZE ACROSS A WIDESPREAD ENOUGH AREA ACROSS THESE REGION...THEN LATER SHIFTS MAY NEED TO HOIST A RED FLAG WARNING. -KT .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 356 PM MDT THU APR 16 2015 FRIDAY NIGHT THROUGH SATURDAY...MODELS HAVE SHIFTED A BIT OVER THE PST 24 HRS...BUT STILL REMAIN FAIRLY CONSISTENT WITH THE PLACEMENT AND PATH OF THE UPPER LOW. FRIDAY NIGHT THE LOW PRESSURE SYSTEM IS FORECAST TO BE CENTERED RIGHT OVER COLORADO...THEN OVER THE NEXT 24 HRS IT WILL WOBBLE A BIT BEFORE SLOWLY EXITING THE STATE VIA THE EASTERN BORDER. THIS PATTERN WOULD IMPLY THAT THE MTS...ESPECIALLY THE CONTDVD...WILL GET THE BRUNT OF SNOWFALL...MAINLY THROUGH FRIDAY NIGHT. THEREFORE...ONGOING WINTER HIGHLIGHTS RUNNING THROUGH 12Z SATURDAY LOOK REASONABLE. SNOW AMOUNTS WILL THEN TAPER OVER OVER THE DAY SATURDAY AS TEMPS BEGIN TO WARM AND THE SYSTEM WEAKENS. ISOLATED TO SCATTERED SHOWERS ARE FORECAST FOR THE REMAINDER OF THE LOWER ELEVATIONS...AND TEMPS DO NOT LOOK PARTICULARLY COLD WITH MIN TEMPS IN THE 30S TO AROUND 40 F FOR THE PLAINS...AND MAX TEMPS SATURDAY IN THE MID 50S TO LOWER 60S. SUNDAY AND MONDAY...THE UPPER SYSTEM WEAKENS AND EXITS TO THE EAST LATE SATURDAY...WITH BRISK NW FLOW ALOFT THEN SETTLING IN ACROSS THE STATE. A COUPLE OF UPPER SHORTWAVES ARE EXPECTED TO DROP DOWN ACROSS THE STATE ON BOTH DAYS...KEEPING THE THREAT OF SHOWER ACTIVITY FOR THE CWA IN PLACE. LOOK FOR SCATTERED SHOWERS OVER THE HIGHER TERRAIN...AND ISOLATED SHOWERS FOR THE PLAINS...WITH MAX TEMPS BOTH DAYS HOVERING IN THE 50S TO NEAR 60 F. TUESDAY THROUGH THURSDAY...CONFIDENCE IS FAIRLY LOW FOR WHAT HAPPENS BEYOND MONDAY...THOUGH LONG RANGE MODELS SEEM TO AGREE ON THE QUESTION MARK. A TEMPORARY RIDGE BUILDS INTO THE DESERT SW STARTING TUE...HELPING TO LOWERING PCPN CHANCES AS WELL AS BOOSTING MAX TEMPS FOR THE PLAINS BACK INTO THE 70S. TWO SEPARATE UPPER CLOSED LOW SYSTEMS APPROACH STARTING WED NIGHT...ONE OVER THE PAC NW AND THE OTHER OVER S CA...BUT THIS PATTERN WILL MOST LIKELY GO THROUGH MULTIPLE ADJUSTMENTS BEFORE THEN. MOORE && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 356 PM MDT THU APR 16 2015 CURRENTLY...VFR TO MVFR CONDITIONS FOR THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS AS WELL AS FOR MUCH OF THE LOWER ELEVATIONS. FOR ELEVATIONS ABOVE ROUGHLY 7000 FT...IFR CONDITIONS PREVAILED DUE TO EXTENSIVE LOWER CLOUD COVER AND ONGOING SNOW SHOWERS. THE UPPER LOW WILL SLOWLY MOVE FROM THE SW QUAD TO THE CENTRAL PORTIONS OF THE STATE OVER THE NEXT 24 HRS...BRINGING WAVES OF RAIN/SNOW SHOWERS TO THE LOWER ELEVATIONS AND SNOW...HEAVY AT TIMES...TO THE MTS. EXPECT MVFR CONDITIONS FOR KPUB AND KALS OVER THE NEXT 24 HRS. KCOS IS EXPECTED TO DIP INTO IFR CONDITIONS THIS EVENING...THEN BRIEFLY DROP DOWN INTO LIFR AFTER 11Z TOMORROW MORN. CONDITIONS ACROSS THE HIGHER TERRAIN AND MT PASSES WILL REMAIN IFR TO LIFR. MOORE && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ059-062- 063-074-075. WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ077>079. WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058-060-061- 072-073-080-082. WINTER STORM WARNING UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR COZ076- 081. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR COZ066. WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ084. && $$ UPDATE...ROSE SHORT TERM...KT LONG TERM...MOORE AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
936 AM MDT WED APR 15 2015 .UPDATE... ISSUED AT 936 AM MDT WED APR 15 2015 CHALLENGING FORECAST FOR TODAY FOR NORTHEAST COLORADO. A SURFACE LOW WILL SHIFT EAST ACROSS NORTHEAST COLORADO THROUGH THE DAY. THERE WILL BE NORTH TO NORTHWEST WINDS BEHIND IT AND A DRY LINE DRAPED OVER EASTERN COLORADO. EAST OF THE DRY LINE DEW POINTS SHOULD CLIMB INTO THE 40S WITH SURFACE BASED CAPES AROUND 1000 J/KG. COULD SEE A SEVERE STORM EAST OF THIS DRY LINE. FOR THE FORECAST AREA...BEST CHANCE WOULD BE OVER THE FAR NORTHEAST CORNER AND POSSIBLY EASTERN WASHINGTON COUNTY. HAVE LITTLE FAITH IN THE HRRR AND RAP FOR SHORT TERM DETAILS. IT SHOWS SOUTHERLY WINDS SHIFTING NORTH THROUGH THE LATE MORNING HOURS. HOWEVER...RADAR IS SHOWING NORTH TO NORTHWEST WINDS PROGRESSING SOUTH AT THIS TIME. EXPECT THESE NORTHERLY WINDS TO KEEP MORE MOISTURE OVER THE FRONT RANGE LATE THIS AFTERNOON AND EVENING THAN MOST OF THE MODELS ARE SHOWING. CURRENT FORECAST CALLS FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS...WILL CONTINUE WITH THIS EVEN THOUGH THE HIRES SHORT TERM MODELS ARE DRY. WARMED TEMPERATURES OVER THE EASTERN PLAINS WHERE SOUTHERLY WINDS WILL PUSH TEMPERATURES TO NEAR 70 DEGREES AND ALSO LOWERED DEW POINTS BEHIND THE DRY LINE. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 441 AM MDT WED APR 15 2015 MOST OF THE PLAINS WILL SEE ANOTHER BREEZY DAY TODAY AS A SURFACE LOW REMAINS OVER THE NORTHEAST QUARTER OF THE STATE. AT THE SAME TIME...SOUTHWEST FLOW AT MID-LEVELS WILL BE INCREASING AS AN UPPER LOW INTENSIFIES OVER WESTERN COLORADO AND MOVES INTO POSITION OVER THE FOUR-CORNERS AREA. DYNAMIC FORCING ASSOCIATED WITH THE UPPER LOW WILL PRODUCE SCATTERED SNOW SHOWERS OVER THE MOUNTAINS. THE PLAINS WILL REMAIN DRY THROUGH LATE AFTERNOON DUE TO THE STRONG DOWNSLOPING EFFECT OF THE SOUTHWEST WINDS ROTATING AROUND THE DEVELOPING STORM SYSTEM. BY LATER THIS EVENING...A SURFACE COLD FRONT WILL DROP DOWN THE FRONT RANGE FROM THE NORTH. THIS WILL SWITCH THE WINDS TO A NORTHERLY DIRECTION AND BRING COOLING TEMPERATURES. SHOWER ACTIVITY WILL ALSO SPREAD ONTO THE NORTHERN PLAINS LATE IN THE AFTERNOON AND THEN FILL IN SOUTHWARD THROUGH THE EVENING. TEMPERATURES SHOULD REMAIN WARM ENOUGH THROUGH THE EVENING THAT PRECIPITATION ACROSS THE PLAINS REMAINS AS RAIN. AFTER MIDNIGHT...THE AIRMASS WILL BECOME COOL ENOUGH FOR PRECIPITATION TO CHANGE OVER TO SNOW. ALTHOUGH WITH LOW TEMPERATURES ONLY AROUND THE FREEZING MARK...THE SNOW WILL HAVE A HARD TIME ACCUMULATING. ADDITIONAL SNOW ACCUMULATIONS AT LOWER ELEVATIONS IS NOT EXPECTED UNTIL LATER IN THE STORM CYCLE. MOUNTAINS AREAS MAY PICK UP A FEW INCHES OF SNOWFALL OVERNIGHT...BUT THE HEAVIEST PRECIPITATION IS NOT EXPECTED UNTIL LATER IN THE STORM...IF IT REMAINS OVER THE STATE LONG ENOUGH. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 441 AM MDT WED APR 15 2015 OVERALL MODELS HAVE COME INTO BETTER AGREEMENT TONIGHT WITH AN UPPER LEVEL LOW BEING CENTERED NR THE FOUR CORNERS AREA AT 12Z THU WHICH WILL STAY NEARLY STATIONARY OR DRIFT SLOWLY SOUTH INTO NWRN NEW MEXICO BY THU NIGHT. BY THU AFTN INTO THU NIGHT A 700 MB LOW WILL BECOME MORE ORGANIZED OVER SRN CO/NRN NM AS SFC HIGH PRES REMAINS OVER WY WHILE SFC LOW PRES IS OVER NM. THIS LEADS TO INCREASING ELY LOW LVL FLOW ESPECIALLY THU NIGHT INTO FRI WHICH MAY ALLOW FOR DEEPER LOW LVL MOISTURE TO ADVECT IN FM THE EAST. MEANWHILE THERE WILL BE MID LVL ASCENT AND FAVORABLE LAPSE RATES ACROSS THE AREA AS WELL. OVERALL THERE APPEARS TO BE AN INCREASING THREAT FOR HEAVY WET SNOW THU NIGHT INTO FRI IN THE MTNS AND FOOTHILLS. AT LOWER ELEVATIONS BUFFER DATA SUGGEST SNOW LEVELS WILL BE GENERALLY ABOVE 5500 FEET WITH A RAIN/SNOW MIX BETWEEN 5000 AND 5500 FT. ON FRI THE MODELS BEGIN TO DIVERGE WITH THE MOVEMENT OF THE UPPER LEVEL LOW. THE ECMWF AND TO SOME EXTENT THE GFS BEGIN TO LIFT A SIGNIFICANT PIECE OF ENERGY INTO ERN CO WHICH ALLOWS FOR THE UPPER LEVEL LOW TO MOVE ENE INTO SCNTRL OR SERN CO BY FRI AFTN. MEANWHILE THE GEM MODEL KEEPS THE MAIN UPPER LEVEL LOW BACK OVER SWRN CO/NWRN NM THRU FRI AFTN. AT THIS POINT NOT SURE WHICH SOLUTION IS THE BEST HOWEVER WITH ELY UPSLOPE FLOW...MID LVL ASCENT AND DECENT LAPSE RATES STILL IN PLACE SHOULD CONTINUE TO SEE PERIODS OF HEAVIER PCPN THRU FRI AFTN ONE WOULD THINK. BY FRI NIGHT INTO SAT THE GEM MODEL BEGINS TO MOVE MAIN UPPER LEVEL EASTWARD ACROSS NRN NEW MEXICO WITH SOME TYPE OF NRN EXTENSION OVER ERN CO BY SAT AFTN. MEANWHILE THE GFS AND ECMWF SHOW THE MAIN UPPER EVENTUALLY BECOMING MORE ELONGATED FM ERN CO INTO NERN NM AS WELL. THE SREF MEAN SOLUTION STILL HAS A MORE CONSOLIDATED UPPER LEVEL LOW ALONG THE SRN CO/NRN NM BORDER AREA THRU 18Z SAT. OVERALL SHOULD CONTINUE TO SEE SOME PCPN THRU FRI NIGHT HOWEVER CONFIDENCE IN SAT FCST IS RATHER LOW AT THIS POINT. IF THE SYSTEM STAYS MORE CONSOLIDATED LIKE THE SREF SHOWS AND STAYS OVER SRN CO/NRN NM THEN PCPN COULD LINGER WELL INTO SAT. AT THIS TIME THERE IS AN INCREASING THREAT FOR A DECENT SPRING STORM FM THU NIGHT THRU FRI NIGHT SO WILL ISSUE A WATCH FOR THE MTNS AND FOOTHILLS. SNOW LEVELS FRI NIGHT INTO SAT ARE STILL NOT CERTAIN AT LOWER ELEVATIONS SO WILL KEEP A RAIN SNOW MIX BETWEEN 5000 TO 5500 FT WITH RAIN BELOW 5000 FT. ITS POSSIBLE THE FAR WRN AND SRN SUBURBS IN THE 5500-6000 FT RANGE COULD RECEIVE SOME HEAVIER SNOWFALL BUT CONFIDENCE IS NOT HIGH ENOUGH AT THIS TIME TO ISSUE A WATCH. QPF AMOUNTS FM THE MODELS GENERALLY AVERAGE FM 1 TO 2 INCHES OF WATER FOR THE EVENT HOWEVER SOME AREAS COULD RECEIVE UP TO 3 INCHES OF WATER. BY SAT NIGHT INTO SUN THE UPPER LEVEL LOW SHOULD MOVE EAST OF THE AREA HOWEVER AS IT DOES SO A DISTURBANCE IN NW FLOW ALOFT MAY AFFECT THE AREA ON SUN AS ANOTHER PUSH OF COOLER AIR MOVES INTO NERN CO. CROSS-SECTIONS SHOW DECENT MOISTURE AND SOME MID LVL ASCENT WITH THIS FEATURE SO COULD SEE ANOTHER ROUND OF PCPN MAINLY ON SUN. TEMP PROFILE SHOWS AIRMASS WOULD BE COLD ENOUGH FOR SNOW AT LOWER ELEVATIONS SUN MORNING. FOR SUN NIGHT INTO MON ANOTHER DISTURBANCE IN NWLY FLOW ALOFT MAY AFFECT THE AREA ALONG WITH ANOTHER FNT. THUS COULD SEE ANOTHER CHC OF PCPN MAINLY SUN NIGHT INTO MON MORNING. ON TUE NWLY FLOW ALOFT WILL REMAIN OVER THE AREA. THE GFS SHOWS ANOTHER DISTURBANCE AND FNT AFFECTING NRN CO BRINGING ANOTHER CHC OF PCPN WHILE THE ECMWF DOES NOT. FOR NOW WILL JUST KEEP IN LOW POPS. && .AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING) ISSUED AT 936 AM MDT WED APR 15 2015 NORTH TO NORTHWEST WINDS WILL PREVAIL AT THE DENVER AIRPORTS THROUGH THE EVENING HOURS. DEPENDING ON WHERE THE SURFACE LOW MOVES...A PERIOD OF SOUTHWEST TO WEST WINDS WILL BE POSSIBLE...WITH THE BEST CHANCE BEING AT KAPA. MAY BE SOME GUST TO 30 TO 40 KNOTS THIS EVENING AS A FRONT PUSHES THROUGH. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED BETWEEN 22Z AND 03Z...WITH SHOWERS POSSIBLE THROUGH THE NIGHT. CEILINGS WILL FALL AFTER 00Z AS THE AIRMASS MOISTENS. AFTER 06Z...CEILINGS WILL LIKELY DROP BELOW 3000 FEET. SNOW WILL BE POSSIBLE AFTER 06ZZ...THOUGH ANY SNOWFALL SHOULD BE SHORT LIVED. && .FIRE WEATHER... ISSUED AT 441 AM MDT WED APR 15 2015 INCREASING SOUTHWEST WINDS ARE EXPECTED AGAIN BY THIS AFTERNOON ACROSS THE PALMER DIVIDE REGION AND SOUTHERN LINCOLN COUNTY. WARM ENOUGH TEMPERATURES AND LOW ENOUGH DEW POINTS ARE ALSO EXPECTED WHICH MAY PRODUCE ANOTHER AFTERNOON OF FIRE WEATHER CONCERNS. WILL ISSUE A RED FLAG WARNING FOR ZONE 47 TO HIGHLIGHT THE THREAT OF DANGEROUS FIRE BEHAVIOR FOR ANOTHER DAY. THE REMAINDER OF NORTHEAST COLORADO IS EXPECTED TO BE SOME 10 TO 15 DEGREES COOLER TODAY THAN YESTERDAY...SO FIRE DANGERS ARE NOT EXPECTED TO BE AS HIGH. && .BOU WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ247. WINTER STORM WATCH FROM THURSDAY EVENING THROUGH LATE FRIDAY NIGHT FOR COZ033>036. && $$ UPDATE...MEIER SHORT TERM...DANKERS LONG TERM...RPK AVIATION...MEIER FIRE WEATHER...DANKERS
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
253 AM MDT WED APR 15 2015 .UPDATE... ISSUED AT 246 AM MDT WED APR 15 2015 ALLOWED HIGH WIND WARNINGS AND WIND ADVISORIES TO EXPIRE. WEATHER STATIONS ALONG THE FRONT IN WESTERN COLORADO ARE STILL REPORTING GUSTS TO 30 MPH...BUT THE WORST IS OVER AND WINDS WILL CONTINUE TO SUBSIDE THROUGH THE MORNING HOURS. UPDATE ISSUED AT 938 PM MDT TUE APR 14 2015 RED FLAG WARNINGS WERE ALLOWED TO EXPIRE. RELATIVE HUMIDITY VALUES HAVE REACHED ABOVE 15% IN MANY LOCATIONS AND WILL CONTINUE TO RISE OVERNIGHT. WINDS WILL CONTINUE TO GUST AS THE COLD FRONT PASSES THROUGH TONIGHT. GUSTY WINDS WILL ALSO SURFACE FROM OUTFLOW OF SHOWERS AND TSTORMS TONIGHT. UPDATE ISSUED AT 649 PM MDT TUE APR 14 2015 STRONG COLD FRONT CONTINUES TO MAKE SLOW PROGRESS ACROSS UTAH EARLY THIS EVENING AND WILL BE PUSHING IN OUR EASTERN UTAH ZONES OVER THE NEXT FEW HOURS AND INTO FAR WESTERN COLORADO AROUND 9 PM THIS EVENING. STRONG SFC WINDS WILL REMAIN IN PLACE THROUGH LATE TONIGHT AND CURRENT WIND HIGHLIGHTS THROUGH 3 AM REMAIN ON TRACK. LATEST LAMP GUIDANCE SUGGESTS WINDS EXCEEDING 60 MPH STILL POSSIBLE ACROSS PORTIONS OF EASTERN UTAH AND FAR NORTHWEST COLORADO AND NO ADJUSTMENTS TO HIGHLIGHTS NEEDED ATTM. FEW HIGH BASED SHOWERS WILL ADD TO GUST POTENTIAL THROUGH THIS EVENING. PEAK GUSTS SO FAR THIS EVENING HAVE BEEN IN THE 50 TO 59 MPH RANGE AND GENERALLY CONFINED TO OUR EAST CENTRAL UTAH ZONES. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 411 PM MDT TUE APR 14 2015 THE APPROACHING UPPER TROUGH IS CURRENTLY CENTERED OVER EASTERN NEVADA PER LATEST WATER VAPOR IMAGERY AND RAP ANALYSIS WITH ASSOCIATED COLD FRONT HAVING ALREADY CROSSED THE NORTHWESTERN QUADRANT OF UTAH. THE FRONT IS EXPECTED TO REACH NORTHEAST AND EAST-CENTRAL UTAH BY 00Z...THEN CROSS INTO WESTERN COLORADO DURING THE EVENING HOURS. STRONG WINDS HAVE MATERIALIZED OVER THE FORECAST AREA...ESPECIALLY UTAH AND NORTHWEST COLORADO ZONES WITH MANY REPORTS OF GUSTS OVER 40 MPH. WINDS SHOULD CONTINUE TO INCREASE THROUGH THE REMAINDER OF THE AFTERNOON AND INTO THE EVENING HOURS...REMAINING GUSTY ON BOTH SIDES OF THE COLD FRONT. GOING WIND HIGHLIGHTS LOOK GOOD AND WILL CONTINUE THROUGH LATE TONIGHT. SOME CUMULUS BLOWUPS ARE CURRENTLY SEEN ON SATELLITE ALTHOUGH NOT MUCH IN THE WAY OF SHOWERS ARE EVIDENT AS OF YET. SOME PREFRONTAL SHOWERS ARE STILL POSSIBLE THROUGH THIS EVENING BUT EXPECT PRECIPITATION TO FILL IN MORE BEHIND THE FRONT. SNOW LEVELS WILL LOWER QUICKLY WITH HIGHER VALLEYS STARTING TO SEE A THREAT OF SNOW LATE TONIGHT. HOWEVER...THE TROUGH IS EXPECTED TO PINCH OFF INTO A CLOSED LOW TONIGHT WHICH WILL SLOW ITS EASTWARD PROGRESSION AND WEAKEN THE FRONT AS IT CONTINUES THROUGH THE EASTERN PORTIONS OF THE FORECAST AREA. AS SUCH...PRECIPITATION AMOUNTS/RATES ARE NOT EXPECTED TO BE VERY SIGNIFICANT. THE LOW CENTER WILL REMAIN NEAR THE UTAH/COLORADO BORDER TOMORROW BEFORE SETTLING OVER THE FOUR CORNERS AREA BY TOMORROW NIGHT. THIS WILL KEEP UNSETTLED WEATHER OVER THE AREA TOMORROW. WITH MUCH COLDER AIR FILTERING BEHIND THE FRONT...EXPECT MAX TEMPERATURES TOMORROW 25-30 DEGREES COOLER ACROSS MANY AREAS. THIS COOLER AIR WILL ALSO BRING A POTENTIAL FOR FREEZING TEMPERATURES TOMORROW NIGHT. A FREEZE WATCH REMAINS IN EFFECT AS A RESULT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 411 PM MDT TUE APR 14 2015 THE OPERATIONAL GFS IS MORE PROGRESSIVE THAN THE ECMWF/GEM SOLUTION REGARDING THE CLOSED LOW...WITH CONSIDERABLE SPREAD AMONG THE GFS ENSEMBLES. HAVE SIDED MORE IN LINE WITH THE EC/GEM WHICH KEEPS THE LOW IN THE VICINITY OF THE FOUR CORNERS THROUGH FRIDAY. ALTHOUGH THE AIRMASS GRADUALLY TRENDS WARMER DURING THIS TIME...MOIST AND SOMEWHAT UNSTABLE CONDITIONS WILL KEEP A THREAT OF SHOWERS ACROSS THE AREA...MOSTLY ACROSS THE HIGHER TERRAIN. PRECIPITATION IS NOT EXPECTED TO BE VERY HEAVY DUE TO EAST/NORTHEAST FLOW BUT LONG DURATION OF THE EVENT COULD LEAD TO SEVERAL INCHES LOCALLY. MOUNTAINS FARTHER SOUTH SUCH AS THE SAN JUANS WILL BE CLOSER TO THE LOW AND RESULTING WEAKER FLOW COULD ALLOW FOR BETTER ACCUMULATIONS. THE LOW WILL FINALLY EXIT THE AREA OVER THE WEEKEND AND YIELD TO A SLIGHTLY CYCLONIC NORTHWEST FLOW ALOFT. A GRADUAL WARMING TREND WILL TAKE PLACE DURING THIS TIME AND INTO THE EARLY PART OF NEXT WEEK. HOWEVER...MODELS CONTINUE TO GENERATE A FEW SHOWERS OVER THE HIGH TERRAIN WITH WEAK RIPPLES EMBEDDED IN THE FLOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 951 PM MDT TUE APR 14 2015 THE COLD FRONT HAS REACHED KGJT AND IS RUNNING ALONG A SOUTHWEST TO NORTHEAST AXIS WHICH WILL SOON BE REACHING KMTJ...KTEX...AND KRIL SHORTLY. GUSTY 25-35 KTS WINDS WILL CONTINUE TO BE WIDESPREAD ACROSS THE FORECAST AREA AS THIS FRONT PASSES AND BEHIND THE FRONT FOR A FEW HOURS AS WEST NORTHWEST WINDS BRING MUCH COOLER AIR TO THE REGION. PRECIPITATION BEHIND THE FRONT IS EXPECTED TO BE SCATTERED IN NATURE...BECOMING ALL SNOW AT HIGHER ELEVATIONS. PERIODS OF IFR CONDITIONS CANNOT BE RULED OUT WITH ANY SHOWERS THAT MOVE OVER THE TAF SITES. && .FIRE WEATHER... ISSUED AT 411 PM MDT TUE APR 14 2015 A STRONG COLD FRONT WILL APPROACH THE AREA OVERNIGHT INTO WEDNESDAY MORNING. THIS WILL CONTINUE TO BRING STRONG WINDS TO MUCH OF THE AREA...WITH WIND GUSTS UP TO 65 MPH POSSIBLE. THIS COLD FRONT WILL REACH NORTHEASTERN UTAH LATER THIS EVENING...ARRIVING ACROSS SOUTH CENTRAL COLORADO BY WEDNESDAY MORNING. EXPECT A SUBSTANTIAL DROP IN TEMPERATURES WILL THIS FRONT ALONG WITH ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE HIGHER TERRAIN. COOLER AND UNSETTLED WEATHER REMAIN IN PLACE THROUGH THE END OF THE WEEK. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WIND ADVISORY UNTIL 3 AM MDT EARLY THIS MORNING FOR COZ002-003- 006>008-011-020-021. HIGH WIND WARNING UNTIL 3 AM MDT EARLY THIS MORNING FOR COZ001- 006. FREEZE WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR COZ001-006-011. UT...WIND ADVISORY UNTIL 3 AM MDT EARLY THIS MORNING FOR UTZ023-025- 028. HIGH WIND WARNING UNTIL 3 AM MDT EARLY THIS MORNING FOR UTZ022- 024-027-029. FREEZE WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR UTZ022-024-027-029. && $$ UPDATE...JAM SHORT TERM...LC LONG TERM...LC AVIATION...TGJT FIRE WEATHER...CK
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1157 PM MDT TUE APR 14 2015 .UPDATE... ISSUED AT 938 PM MDT TUE APR 14 2015 RED FLAG WARNINGS WERE ALLOWED TO EXPIRE. RELATIVE HUMIDITY VALUES HAVE REACHED ABOVE 15% IN MANY LOCATIONS AND WILL CONTINUE TO RISE OVERNIGHT. WINDS WILL CONTINUE TO GUST AS THE COLD FRONT PASSES THROUGH TONIGHT. GUSTY WINDS WILL ALSO SURFACE FROM OUTFLOW OF SHOWERS AND TSTORMS TONIGHT. UPDATE ISSUED AT 649 PM MDT TUE APR 14 2015 STRONG COLD FRONT CONTINUES TO MAKE SLOW PROGRESS ACROSS UTAH EARLY THIS EVENING AND WILL BE PUSHING IN OUR EASTERN UTAH ZONES OVER THE NEXT FEW HOURS AND INTO FAR WESTERN COLORADO AROUND 9 PM THIS EVENING. STRONG SFC WINDS WILL REMAIN IN PLACE THROUGH LATE TONIGHT AND CURRENT WIND HIGHLIGHTS THROUGH 3 AM REMAIN ON TRACK. LATEST LAMP GUIDANCE SUGGESTS WINDS EXCEEDING 60 MPH STILL POSSIBLE ACROSS PORTIONS OF EASTERN UTAH AND FAR NORTHWEST COLORADO AND NO ADJUSTMENTS TO HIGHLIGHTS NEEDED ATTM. FEW HIGH BASED SHOWERS WILL ADD TO GUST POTENTIAL THROUGH THIS EVENING. PEAK GUSTS SO FAR THIS EVENING HAVE BEEN IN THE 50 TO 59 MPH RANGE AND GENERALLY CONFINED TO OUR EAST CENTRAL UTAH ZONES. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 411 PM MDT TUE APR 14 2015 THE APPROACHING UPPER TROUGH IS CURRENTLY CENTERED OVER EASTERN NEVADA PER LATEST WATER VAPOR IMAGERY AND RAP ANALYSIS WITH ASSOCIATED COLD FRONT HAVING ALREADY CROSSED THE NORTHWESTERN QUADRANT OF UTAH. THE FRONT IS EXPECTED TO REACH NORTHEAST AND EAST-CENTRAL UTAH BY 00Z...THEN CROSS INTO WESTERN COLORADO DURING THE EVENING HOURS. STRONG WINDS HAVE MATERIALIZED OVER THE FORECAST AREA...ESPECIALLY UTAH AND NORTHWEST COLORADO ZONES WITH MANY REPORTS OF GUSTS OVER 40 MPH. WINDS SHOULD CONTINUE TO INCREASE THROUGH THE REMAINDER OF THE AFTERNOON AND INTO THE EVENING HOURS...REMAINING GUSTY ON BOTH SIDES OF THE COLD FRONT. GOING WIND HIGHLIGHTS LOOK GOOD AND WILL CONTINUE THROUGH LATE TONIGHT. SOME CUMULUS BLOWUPS ARE CURRENTLY SEEN ON SATELLITE ALTHOUGH NOT MUCH IN THE WAY OF SHOWERS ARE EVIDENT AS OF YET. SOME PREFRONTAL SHOWERS ARE STILL POSSIBLE THROUGH THIS EVENING BUT EXPECT PRECIPITATION TO FILL IN MORE BEHIND THE FRONT. SNOW LEVELS WILL LOWER QUICKLY WITH HIGHER VALLEYS STARTING TO SEE A THREAT OF SNOW LATE TONIGHT. HOWEVER...THE TROUGH IS EXPECTED TO PINCH OFF INTO A CLOSED LOW TONIGHT WHICH WILL SLOW ITS EASTWARD PROGRESSION AND WEAKEN THE FRONT AS IT CONTINUES THROUGH THE EASTERN PORTIONS OF THE FORECAST AREA. AS SUCH...PRECIPITATION AMOUNTS/RATES ARE NOT EXPECTED TO BE VERY SIGNIFICANT. THE LOW CENTER WILL REMAIN NEAR THE UTAH/COLORADO BORDER TOMORROW BEFORE SETTLING OVER THE FOUR CORNERS AREA BY TOMORROW NIGHT. THIS WILL KEEP UNSETTLED WEATHER OVER THE AREA TOMORROW. WITH MUCH COLDER AIR FILTERING BEHIND THE FRONT...EXPECT MAX TEMPERATURES TOMORROW 25-30 DEGREES COOLER ACROSS MANY AREAS. THIS COOLER AIR WILL ALSO BRING A POTENTIAL FOR FREEZING TEMPERATURES TOMORROW NIGHT. A FREEZE WATCH REMAINS IN EFFECT AS A RESULT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 411 PM MDT TUE APR 14 2015 THE OPERATIONAL GFS IS MORE PROGRESSIVE THAN THE ECMWF/GEM SOLUTION REGARDING THE CLOSED LOW...WITH CONSIDERABLE SPREAD AMONG THE GFS ENSEMBLES. HAVE SIDED MORE IN LINE WITH THE EC/GEM WHICH KEEPS THE LOW IN THE VICINITY OF THE FOUR CORNERS THROUGH FRIDAY. ALTHOUGH THE AIRMASS GRADUALLY TRENDS WARMER DURING THIS TIME...MOIST AND SOMEWHAT UNSTABLE CONDITIONS WILL KEEP A THREAT OF SHOWERS ACROSS THE AREA...MOSTLY ACROSS THE HIGHER TERRAIN. PRECIPITATION IS NOT EXPECTED TO BE VERY HEAVY DUE TO EAST/NORTHEAST FLOW BUT LONG DURATION OF THE EVENT COULD LEAD TO SEVERAL INCHES LOCALLY. MOUNTAINS FARTHER SOUTH SUCH AS THE SAN JUANS WILL BE CLOSER TO THE LOW AND RESULTING WEAKER FLOW COULD ALLOW FOR BETTER ACCUMULATIONS. THE LOW WILL FINALLY EXIT THE AREA OVER THE WEEKEND AND YIELD TO A SLIGHTLY CYCLONIC NORTHWEST FLOW ALOFT. A GRADUAL WARMING TREND WILL TAKE PLACE DURING THIS TIME AND INTO THE EARLY PART OF NEXT WEEK. HOWEVER...MODELS CONTINUE TO GENERATE A FEW SHOWERS OVER THE HIGH TERRAIN WITH WEAK RIPPLES EMBEDDED IN THE FLOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 951 PM MDT TUE APR 14 2015 THE COLD FRONT HAS REACHED KGJT AND IS RUNNING ALONG A SOUTHWEST TO NORTHEAST AXIS WHICH WILL SOON BE REACHING KMTJ...KTEX...AND KRIL SHORTLY. GUSTY 25-35 KTS WINDS WILL CONTINUE TO BE WIDESPREAD ACROSS THE FORECAST AREA AS THIS FRONT PASSES AND BEHIND THE FRONT FOR A FEW HOURS AS WEST NORTHWEST WINDS BRING MUCH COOLER AIR TO THE REGION. PRECIPITATION BEHIND THE FRONT IS EXPECTED TO BE SCATTERED IN NATURE...BECOMING ALL SNOW AT HIGHER ELEVATIONS. PERIODS OF IFR CONDITIONS CANNOT BE RULED OUT WITH ANY SHOWERS THAT MOVE OVER THE TAF SITES. && .FIRE WEATHER... ISSUED AT 411 PM MDT TUE APR 14 2015 A STRONG COLD FRONT WILL APPROACH THE AREA OVERNIGHT INTO WEDNESDAY MORNING. THIS WILL CONTINUE TO BRING STRONG WINDS TO MUCH OF THE AREA...WITH WIND GUSTS UP TO 65 MPH POSSIBLE. THIS COLD FRONT WILL REACH NORTHEASTERN UTAH LATER THIS EVENING...ARRIVING ACROSS SOUTH CENTRAL COLORADO BY WEDNESDAY MORNING. EXPECT A SUBSTANTIAL DROP IN TEMPERATURES WILL THIS FRONT ALONG WITH ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE HIGHER TERRAIN. COOLER AND UNSETTLED WEATHER REMAIN IN PLACE THROUGH THE END OF THE WEEK. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WIND ADVISORY UNTIL 3 AM MDT WEDNESDAY FOR COZ002-003-006>008- 011-020-021. HIGH WIND WARNING UNTIL 3 AM MDT WEDNESDAY FOR COZ001-006. FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING FOR COZ001-006-011. UT...WIND ADVISORY UNTIL 3 AM MDT WEDNESDAY FOR UTZ023-025-028. HIGH WIND WARNING UNTIL 3 AM MDT WEDNESDAY FOR UTZ022-024-027- 029. FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING FOR UTZ022-024-027-029. && $$ UPDATE...JAM SHORT TERM...LC LONG TERM...LC AVIATION...TGJT FIRE WEATHER...CK
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1241 PM EDT WED APR 15 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD ACROSS OUR REGION TODAY AND TONIGHT, THEN SHIFT OFFSHORE THURSDAY INTO FRIDAY. A COLD FRONT WILL MOVE THROUGH FRIDAY AS LOW PRESSURE DEVELOPS NEAR THE NORTH CAROLINA COAST, THEN A SECONDARY COLD FRONT ARRIVES DURING SATURDAY. HIGH PRESSURE IS SCHEDULED TO BRIEFLY BUILD IN FOR SUNDAY, THEN THE NEXT COLD FRONT AND LOW PRESSURE SYSTEM MOVES IN FOR LATER MONDAY AND TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH PRESSURE WILL CONTINUE TO BUILD TOWARD THE REGION TODAY. THIS WILL ALLOW FOR A CONTIUATION OF MOSTLY SUNNY SKIES AND STRONG NORTHERLY WINDS. DEWPOINTS HAVE BEEN DROPPING ACROSS MOST OF THE REGION THIS MORNING AND RUNNING QUITE A BIT LOWER THAN WHAT THE SOME OF THE GUIDANCE SUGGESTS. IN THE NEAR TERM CONTINUED TO LEAN CLOSER TO THE MET GUIDANCE BUT EVEN THIS IS TO HIGH, LOWERED DEWPOINTS ON THE 12:30PM UPDATE TO ACCOUNT FOR THE DRY AIRMASS. WITH MOSTLY SUNNY CONDITIONS TODAY, TEMPERATURES HAVE REPSONDED NICELY ACROSS THE REGION SOME MINOR ADJUSTMENTS WERE MADE WITH THE UPDATE OTHERWISE MOST OF US SHOULD SEE HIGHS WELL INTO THE 60`S. THE MAIN WEATHER PLAYER WILL BE THE STRONG NORTHERLY WIND GUSTS AROUND 25 MPH. HRRR AND RAP SOUNDINGS CONTINUE TO SUGGEST WIND GUSTS MAY PERSIST THROUGH THE AFTERNOON AND DID RAISE THEM A BIT WITH THE LATEST UPDATE. FIRE WEATHER CONCERNS, EXIST AS WELL WITH A RED FLAG WARNING UP FOR CENTRAL AND NORTHERN NJ ALONG WITH EASTERN PA, PLEASE SEE FIRE WEATHER SECTION FOR MORE. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/... 500 MB SHORT WAVE RIDGE SLIDES OVER THE REGION, AS THE SURFACE HIGH BUILDS CLOSER. ADDITIONALLY, THE 250MB LEVEL JET SLIDES FURTHER OFF SHORE, ALL OF THIS WILL COMBINE FOR CLEARING SKIES OVERNIGHT. WINDS SHOULD BE LIGHT, AND WITH THE RELATIVELY LOW DEW POINT TEMPERATURES, SHOULD SEE CONSIDERABLE RADIATIONAL COOLING. AS A RESULT, EXPECT LOWS IN THE UPPER 30S TO LOWER 40S. AT THIS TIME, HOWEVER, DO NOT EXPECT FROST ADVISORY CONDITIONS IN LOCATIONS WHERE THE GROWING SEASON HAS ALREADY STARTED (IN THESE AREAS EXPECT LOWS MOSTLY IN THE LOWER 40S). && .LONG TERM /THURSDAY THROUGH TUESDAY/... THE SYNOPTIC SETUP IS COMPRISED OF AN INITIAL RIDGE IN THE EAST THAT TRANSITIONS TO SOME TROUGHING. AS THIS OCCURS, A CLOSED LOW ACROSS THE WEST DROPS EAST-SOUTHEAST EVENTUALLY EJECTING ACROSS THE PLAINS. THIS FEATURE BUILDS SOME RIDGING DOWNSTREAM, HOWEVER IT ALSO FORCES SOME AMPLIFICATION OF THE TROUGH ACROSS THE NORTHEAST FOR A PORTION OF THE WEEKEND. THE CLOSED LOW MAY THEN GET ABSORBED INTO A LARGE SCALE TROUGH FROM THE MIDWEST AS IT UNDERGOES AMPLIFICATION EASTWARD EARLY NEXT WEEK. PRIOR TO THIS OCCURRING, A SURFACE LOW IS FORECAST TO DEVELOP NEAR THE NORTH CAROLINA COAST THURSDAY AND THEN TRACK NORTHEASTWARD. THE DETAILS WITHIN THIS SETUP IS OF LOWER CONFIDENCE AS THE MODEL GUIDANCE IS HAVING TROUBLE HANDLING THE SPLIT FLOW. THE INTERACTION OF THE EJECTING CLOSED LOW AND THE NORTHERN STREAM TROUGH AND ASSOCIATED ENERGY WILL HAVE AN IMPACT ON THE DOWNSTREAM WEATHER. THIS IS MOST NOTED FOR OUR AREA DURING THE WEEKEND AND ESPECIALLY EARLY NEXT WEEK. GIVEN THE LOWER CONFIDENCE, WE USED A MODEL BLEND WITH CONTINUITY FOR WEDNESDAY THROUGH FRIDAY THEN WENT WITH MOSTLY THE 00Z WPC GUIDANCE /BLEND OF THE MEANS SATURDAY, THEN MOSTLY A NAEFS/ECMWF ENSEMBLE MEAN BLEND THEREAFTER/. SOME ADJUSTMENTS WERE THEM MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR NEIGHBORING OFFICES. FOR THURSDAY...HIGH PRESSURE AT THE SURFACE IS FORECAST TO SHIFT TO OUR EAST DURING THIS TIME FRAME. THIS WILL SET THE STAGE FOR SOUTHEASTERLY LOW-LEVEL FLOW THAT WILL ALLOW FOR MOISTURE ADVECTION TO INCREASE. IT APPEARS THAT A PRESSURE TROUGH DEVELOPS ALONG THE NORTH CAROLINA COAST AS DEPARTING HIGH PRESSURE WEDGES SOUTHWESTWARD FOR A TIME. AS A RESULT, LOW PRESSURE IS FORECAST TO DEVELOP NEAR OR ALONG THE NORTH CAROLINA COAST. THERE MAY BE A CONDUIT OF MOISTURE PULLED NORTHWESTWARD FROM THIS SURFACE LOW AS IT SLOWLY TRACKS NORTHEASTWARD. OTHERWISE, AN INCOMING COLD FRONT SHOULD ALSO HAVE SOME SHOWERS WITH IT. OVERALL, MUCH OF THIS TIME FRAME SHOULD BE DRY WITH ANY SHOWERS TENDING TO HOLD OFF UNTIL LATER THURSDAY NIGHT AND THIS IS WHEN THE POPS INCREASE. FOR FRIDAY AND SATURDAY...IT MAY START OUT RATHER UNSETTLED FRIDAY AS MOISTURE GETS PULLED NORTHWARD FROM LOW PRESSURE NEAR THE NORTH CAROLINA COAST. THIS FEATURE WILL THEN TRACK FARTHER AWAY FROM THE COAST LATER FRIDAY AND SATURDAY, ALTHOUGH A SECONDARY COLD FRONT SHOULD ARRIVE DURING SATURDAY. THERE IS LESS CONFIDENCE IN THE AMOUNT OF SHOWERS FRIDAY AS IT WILL DEPEND ON HOW MUCH INTERACTION THE SURFACE LOW TO OUR SOUTH HAS WITH ENERGY SLIDING BY FARTHER TO THE NORTH. AS A RESULT, WE KEPT POPS BELOW LIKELY AND WENT WITH SCATTERED WORDING FOR NOW. THE SECONDARY FRONT ON SATURDAY MAY NOT HAVE MUCH MOISTURE LEFT TO WORK WITH, THEREFORE WE KEPT POPS ON THE LOWER SIDE. IT DOES APPEAR THAT THE AIRMASS MODERATES PRIOR TO THE COLD FRONTAL PASSAGE WITH MANY AREAS GETTING TO AROUND 70 DEGREES DURING THE DAY. FOR SUNDAY THROUGH TUESDAY...HIGH PRESSURE AT THE SURFACE SHOULD BUILD IN BRIEFLY SUNDAY. AS ENERGY EJECTS EASTWARD FROM A CLOSED LOW AND ALSO FROM THE MIDWEST, A COMPLEX SYSTEM MAY EVOLVE EASTWARD WITH TIME. WE KEPT SUNDAY DURING THE DAY DRY DUE TO THE PRESENCE OF HIGH PRESSURE, THEN WAA AND MOISTURE ADVECTION BEGINS TO OVERTAKE THE AREA AT NIGHT. THIS MAY ALLOW FOR SOME SHOWERS TO ARRIVE, ALTHOUGH IT STILL LOOKS LIKE THE MORE UNSETTLED TIME FRAME MAY BE MONDAY AND TUESDAY. THIS WILL DEPEND ON THE EVOLUTION OF THE SPLIT FLOW AS IT MAY TURN INTO AN AMPLIFIED UPPER-LEVEL TROUGH IN THE EAST. AS OF NOW, THE HIGHEST POPS ARE FOR MONDAY HOWEVER THIS WILL PROBABLY CHANGE. GIVEN THE UNCERTAINTY WITH THE DETAILS, WE DID NOT GO ANY HIGHER THAN HIGH CHC POPS. SOME COOLER TEMPERATURES SHOULD RESULT, ESPECIALLY IF THE RAIN IS MORE WIDESPREAD. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. ONLY LINGERING HIGH CIRRUS CLOUDS ARE POSSIBLE. NORTHERLY WINDS WILL LIKELY GUST AT MOST LOCATIONS FROM 18-23 KNOTS THIS AFTERNOON. THE GUSTS WILL TAPER OFF AFTER SUNSET. WINDS ARE EXPECTED TO GRADUALLY SHIFT TO EAST NORTHEASTERLY OVERNIGHT TONIGHT UNDER 10 KNOTS THEN TO EASTERLY IN THE MORNING FROM 8-10 KNOTS. THE WINDS WILL THEN SHIFT SOUTHEASTERLY BY THURSDAY AFTERNOON. OUTLOOK... THURSDAY NIGHT THROUGH SATURDAY... CONDITIONS TENDING TO LOWER TO MVFR WITH SCATTERED SHOWERS LATER THURSDAY NIGHT AND FRIDAY. OUR CONFIDENCE IS ON THE LOWER SIDE WITH THE TIMING AND HOW MUCH RAIN OCCURS. A SECONDARY COLD FRONT MOVES THROUGH DURING SATURDAY, HOWEVER THIS MAY HAVE LIMITED MOISTURE WITH IT. SUNDAY...OVERALL VFR AS HIGH PRESSURE BRIEFLY BUILD IN. && .MARINE... SMALL CRAFT ADVISORY HAS BEEN CANCELLED. WINDS AND SEAS HAVE DROPPED BELOW CRITERIA. A FEW GUSTS NEAR 20 KT WILL BE POSSIBLE THROUGH THE DAY ON THE COASTAL WATERS, BUT SHOULD REMAIN BELOW SCA CRITERIA. OUTLOOK... THURSDAY AND FRIDAY...THE WINDS AND SEAS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY CRITERIA AS THE FLOW OVERALL IS FORECAST TO BE LIGHT ENOUGH. SATURDAY AND SUNDAY...A COLD FRONT MOVES THROUGH DURING SATURDAY THEN HIGH PRESSURE ARRIVES BRIEFLY FOR SUNDAY. THE WINDS APPEAR TO REMAIN BELOW ADVISORY CRITERIA, HOWEVER THE SEAS COULD NEAR 5 FEET FOR A TIME ON THE OCEAN MAINLY IF THE NORTHERLY FLOW AHEAD OF HIGH PRESSURE LASTS LONG ENOUGH AND IS A BIT STRONGER. && .FIRE WEATHER... ALMOST ALL OF THE REGION (WITH THE EXCEPTION OF A FEW COASTAL LOCATIONS) WILL SEE MINIMUM RELATIVE HUMIDITY VALUES NEAR OR BELOW 20 PERCENT. MUCH OF DELMARVA AND FAR SOUTHERN NJ HAD RAIN TOTALS NEAR OR ABOVE 1 INCH YESTERDAY, LEADING TO HIGHER FUEL MOISTURES. FOR THE REST OF THE REGION HOWEVER, THE LIGHT RAIN YESTERDAY DID NOT HAVE MADE A SIGNIFICANT IMPACT ACROSS CENTRAL/NORTHERN NJ AND EASTERN PA ON FUEL MOISTURE AND DRYING OF THE FUEL MOISTURE WILL CONTINUE TODAY. AS FOR WINDS, GUSTS NEAR 25 MPH ARE LIKELY ACROSS THE REGION. HOWEVER, THE TIGHTEST PRESSURE GRADIENT, AND THUS THE STRONGEST WINDS ARE EXPECTED IN THE MORNING BUT WILL LINGER INTO THE AFTERNOON. WE HAVE ISSUED A RED FLAG WARNING FOR EASTERN PA, NORTHERN/CENTRAL NJ UNTIL 7 PM DUE TO A COMBINATION OF LOW MOISTURE IN FINE FUELS, LOW RH 20% OR LOWER AND WIND GUSTS AROUND 25 MPH THROUGH THE AFTERNOON. FOR THURSDAY, THE RELATIVE HUMIDITY VALUES ARE FORECAST TO DROP TO 25-35 PERCENT IN THE AFTERNOON MAINLY FOR NEW JERSEY /AWAY FROM THE COAST/ AND EASTERN PENNSYLVANIA, HOWEVER THE WINDS ARE CURRENTLY FORECAST TO BE 15 MPH OR LESS. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR PAZ054-055- 060>062-070-071-101>106. NJ...RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR NJZ001- 007>010-012>015. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...GORSE NEAR TERM...GAINES/JOHNSON SHORT TERM...JOHNSON LONG TERM...GORSE AVIATION...GAINES/GORSE/JOHNSON MARINE...GORSE/JOHNSON FIRE WEATHER...GAINES/JOHNSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
951 AM EDT WED APR 15 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD ACROSS OUR REGION TODAY AND TONIGHT, THEN SHIFT OFFSHORE THURSDAY INTO FRIDAY. A COLD FRONT WILL MOVE THROUGH FRIDAY AS LOW PRESSURE DEVELOPS NEAR THE NORTH CAROLINA COAST, THEN A SECONDARY COLD FRONT ARRIVES DURING SATURDAY. HIGH PRESSURE IS SCHEDULED TO BRIEFLY BUILD IN FOR SUNDAY, THEN THE NEXT COLD FRONT AND LOW PRESSURE SYSTEM MOVES IN FOR LATER MONDAY AND TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 9:30 AM UPDATE... HIGH PRESSURE WILL CONTINUE TO BUILD WITH CONTINUED DRY AIR ADVECTION. THIS WILL RESULT IN ONLY SOME HIGH CIRRUS THROUGH THE REMAINDER OF THE DAY ACROSS THE REGION. SOUNDINGS OFF OF THE RAP AND HRRR INDICATE SOME WIND GUSTS AROUND 25 MPH WILL BE POSSIBLE FOR THE REMAINDER OF DAY AS WELL, SO INCREASED WIND GUSTS A BIT WITH THIS UPDATE. TEMPERATURES AND DEWPOINTS WERE ALSO ADJUSTED WITH THIS UPDATE. WITH THE DRY AIR ADVECTION CONTINUED TO GO CLOSER TO THE MET BUT EVEN THAT IS LIKELY A HIGH WITH THE DEWPOINTS, THESE WERE LOWERED SLIGHTLY AGAIN. A RED FLAG WARNING HAS BEEN ISSUED FOR NORTHERN/CENTRAL NJ ALONG WITH EASTERN PA FOR RH VALUES AROUND 20%, LOW FINE FUEL MOISTURE AND NORTHERLY WIND GUSTS AROUND 25 MPH. PLEASE SEE FIRE WEATHER SECTION OF AFD FOR MORE. 630 AM UPDATE...MAIN CHANGES WITH THIS UPDATE WERE FOR DEW POINT TEMPERATURES. DEW POINTS HAVE FALLEN A BIT FASTER THAN EXPECTED WITH TEENS AND 20S ALREADY OVER THE POCONOS AND NW NJ. UNDERCUT DEW POINTS SLIGHTLY THROUGH OUT THE DAY, BUT WILL WAIT UNTIL UPSTREAM 12Z SOUNDINGS COME IN BEFORE MAKING ANY SIGNIFICANT CHANGES. PREVIOUS NEAR TERM DISCUSSION...THE COLD FRONT, AND ASSOCIATED LOW, WILL CONTINUE TO SLIDE AWAY FROM THE REGION. IN IT`S WAKE, A COOL AND VERY DRY AIR MASS WILL BUILD IN OVER THE REGION. SEE FIRE WEATHER SECTION BELOW FOR A DISCUSSION OF FIRE WEATHER CONCERNS. DESPITE THE COOLER AIR MASS, TEMPERATURES SHOULD ACTUALLY BE PRETTY CLOSE, IF NOT A BIT ABOVE, NORMAL VALUES TODAY. THE UPPER LEVEL JET IS EXPECTED TO REMAIN JUST NORTHEAST OF THE REGION THROUGH THE DAY TODAY, LEADING TO PERSISTENT THICK CIRRUS CLOUDS, SO WHILE IT WON`T BE COMPLETELY SUNNY, IT SHOULD STILL BE A NICE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/... 500 MB SHORT WAVE RIDGE SLIDES OVER THE REGION, AS THE SURFACE HIGH BUILDS CLOSER. ADDITIONALLY, THE 250MB LEVEL JET SLIDES FURTHER OFF SHORE, ALL OF THIS WILL COMBINE FOR CLEARING SKIES OVERNIGHT. WINDS SHOULD BE LIGHT, AND WITH THE RELATIVELY LOW DEW POINT TEMPERATURES, SHOULD SEE CONSIDERABLE RADIATIONAL COOLING. AS A RESULT, EXPECT LOWS IN THE UPPER 30S TO LOWER 40S. AT THIS TIME, HOWEVER, DO NOT EXPECT FROST ADVISORY CONDITIONS IN LOCATIONS WHERE THE GROWING SEASON HAS ALREADY STARTED (IN THESE AREAS EXPECT LOWS MOSTLY IN THE LOWER 40S). && .LONG TERM /THURSDAY THROUGH TUESDAY/... THE SYNOPTIC SETUP IS COMPRISED OF AN INITIAL RIDGE IN THE EAST THAT TRANSITIONS TO SOME TROUGHING. AS THIS OCCURS, A CLOSED LOW ACROSS THE WEST DROPS EAST-SOUTHEAST EVENTUALLY EJECTING ACROSS THE PLAINS. THIS FEATURE BUILDS SOME RIDGING DOWNSTREAM, HOWEVER IT ALSO FORCES SOME AMPLIFICATION OF THE TROUGH ACROSS THE NORTHEAST FOR A PORTION OF THE WEEKEND. THE CLOSED LOW MAY THEN GET ABSORBED INTO A LARGE SCALE TROUGH FROM THE MIDWEST AS IT UNDERGOES AMPLIFICATION EASTWARD EARLY NEXT WEEK. PRIOR TO THIS OCCURRING, A SURFACE LOW IS FORECAST TO DEVELOP NEAR THE NORTH CAROLINA COAST THURSDAY AND THEN TRACK NORTHEASTWARD. THE DETAILS WITHIN THIS SETUP IS OF LOWER CONFIDENCE AS THE MODEL GUIDANCE IS HAVING TROUBLE HANDLING THE SPLIT FLOW. THE INTERACTION OF THE EJECTING CLOSED LOW AND THE NORTHERN STREAM TROUGH AND ASSOCIATED ENERGY WILL HAVE AN IMPACT ON THE DOWNSTREAM WEATHER. THIS IS MOST NOTED FOR OUR AREA DURING THE WEEKEND AND ESPECIALLY EARLY NEXT WEEK. GIVEN THE LOWER CONFIDENCE, WE USED A MODEL BLEND WITH CONTINUITY FOR WEDNESDAY THROUGH FRIDAY THEN WENT WITH MOSTLY THE 00Z WPC GUIDANCE /BLEND OF THE MEANS SATURDAY, THEN MOSTLY A NAEFS/ECMWF ENSEMBLE MEAN BLEND THEREAFTER/. SOME ADJUSTMENTS WERE THEM MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR NEIGHBORING OFFICES. FOR THURSDAY...HIGH PRESSURE AT THE SURFACE IS FORECAST TO SHIFT TO OUR EAST DURING THIS TIME FRAME. THIS WILL SET THE STAGE FOR SOUTHEASTERLY LOW-LEVEL FLOW THAT WILL ALLOW FOR MOISTURE ADVECTION TO INCREASE. IT APPEARS THAT A PRESSURE TROUGH DEVELOPS ALONG THE NORTH CAROLINA COAST AS DEPARTING HIGH PRESSURE WEDGES SOUTHWESTWARD FOR A TIME. AS A RESULT, LOW PRESSURE IS FORECAST TO DEVELOP NEAR OR ALONG THE NORTH CAROLINA COAST. THERE MAY BE A CONDUIT OF MOISTURE PULLED NORTHWESTWARD FROM THIS SURFACE LOW AS IT SLOWLY TRACKS NORTHEASTWARD. OTHERWISE, AN INCOMING COLD FRONT SHOULD ALSO HAVE SOME SHOWERS WITH IT. OVERALL, MUCH OF THIS TIME FRAME SHOULD BE DRY WITH ANY SHOWERS TENDING TO HOLD OFF UNTIL LATER THURSDAY NIGHT AND THIS IS WHEN THE POPS INCREASE. FOR FRIDAY AND SATURDAY...IT MAY START OUT RATHER UNSETTLED FRIDAY AS MOISTURE GETS PULLED NORTHWARD FROM LOW PRESSURE NEAR THE NORTH CAROLINA COAST. THIS FEATURE WILL THEN TRACK FARTHER AWAY FROM THE COAST LATER FRIDAY AND SATURDAY, ALTHOUGH A SECONDARY COLD FRONT SHOULD ARRIVE DURING SATURDAY. THERE IS LESS CONFIDENCE IN THE AMOUNT OF SHOWERS FRIDAY AS IT WILL DEPEND ON HOW MUCH INTERACTION THE SURFACE LOW TO OUR SOUTH HAS WITH ENERGY SLIDING BY FARTHER TO THE NORTH. AS A RESULT, WE KEPT POPS BELOW LIKELY AND WENT WITH SCATTERED WORDING FOR NOW. THE SECONDARY FRONT ON SATURDAY MAY NOT HAVE MUCH MOISTURE LEFT TO WORK WITH, THEREFORE WE KEPT POPS ON THE LOWER SIDE. IT DOES APPEAR THAT THE AIRMASS MODERATES PRIOR TO THE COLD FRONTAL PASSAGE WITH MANY AREAS GETTING TO AROUND 70 DEGREES DURING THE DAY. FOR SUNDAY THROUGH TUESDAY...HIGH PRESSURE AT THE SURFACE SHOULD BUILD IN BRIEFLY SUNDAY. AS ENERGY EJECTS EASTWARD FROM A CLOSED LOW AND ALSO FROM THE MIDWEST, A COMPLEX SYSTEM MAY EVOLVE EASTWARD WITH TIME. WE KEPT SUNDAY DURING THE DAY DRY DUE TO THE PRESENCE OF HIGH PRESSURE, THEN WAA AND MOISTURE ADVECTION BEGINS TO OVERTAKE THE AREA AT NIGHT. THIS MAY ALLOW FOR SOME SHOWERS TO ARRIVE, ALTHOUGH IT STILL LOOKS LIKE THE MORE UNSETTLED TIME FRAME MAY BE MONDAY AND TUESDAY. THIS WILL DEPEND ON THE EVOLUTION OF THE SPLIT FLOW AS IT MAY TURN INTO AN AMPLIFIED UPPER-LEVEL TROUGH IN THE EAST. AS OF NOW, THE HIGHEST POPS ARE FOR MONDAY HOWEVER THIS WILL PROBABLY CHANGE. GIVEN THE UNCERTAINTY WITH THE DETAILS, WE DID NOT GO ANY HIGHER THAN HIGH CHC POPS. SOME COOLER TEMPERATURES SHOULD RESULT, ESPECIALLY IF THE RAIN IS MORE WIDESPREAD. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. ONLY LINGERING HIGH CIRRUS CLOUDS ARE POSSIBLE, PRIMARILY THROUGH 00Z. NORTHERLY WINDS MAY BRIEFLY GUST NEAR 20 KT THROUGH 21Z, BUT OTHERWISE WINDS SHOULD BE NEAR OR BELOW 10KT. WINDS ARE EXPECTED TO GRADUALLY SHIFT TO EAST NORTHEASTERLY OVERNIGHT TONIGHT. OUTLOOK... THURSDAY THROUGH SATURDAY...VFR THURSDAY WITH INCREASING CLOUDS, THEN CONDITIONS TENDING TO LOWER TO MVFR WITH SCATTERED SHOWERS LATER THURSDAY NIGHT AND FRIDAY. OUR CONFIDENCE IS ON THE LOWER SIDE WITH THE TIMING AND HOW MUCH RAIN OCCURS. A SECONDARY COLD FRONT MOVES THROUGH DURING SATURDAY, HOWEVER THIS MAY HAVE LIMITED MOISTURE WITH IT. SUNDAY...OVERALL VFR AS HIGH PRESSURE BRIEFLY BUILD IN. && .MARINE... SMALL CRAFT ADVISORY HAS BEEN CANCELLED. WINDS AND SEAS HAVE DROPPED BELOW CRITERIA. A FEW GUSTS NEAR 20 KT WILL BE POSSIBLE THROUGH THE DAY ON THE COASTAL WATERS, BUT SHOULD REMAIN BELOW SCA CRITERIA. OUTLOOK... THURSDAY AND FRIDAY...THE WINDS AND SEAS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY CRITERIA AS THE FLOW OVERALL IS FORECAST TO BE LIGHT ENOUGH. SATURDAY AND SUNDAY...A COLD FRONT MOVES THROUGH DURING SATURDAY THEN HIGH PRESSURE ARRIVES BRIEFLY FOR SUNDAY. THE WINDS APPEAR TO REMAIN BELOW ADVISORY CRITERIA, HOWEVER THE SEAS COULD NEAR 5 FEET FOR A TIME ON THE OCEAN MAINLY IF THE NORTHERLY FLOW AHEAD OF HIGH PRESSURE LASTS LONG ENOUGH AND IS A BIT STRONGER. && .FIRE WEATHER... ALMOST ALL OF THE REGION (WITH THE EXCEPTION OF A FEW COASTAL LOCATIONS) WILL SEE MINIMUM RELATIVE HUMIDITY VALUES NEAR OR BELOW 20 PERCENT. MUCH OF DELMARVA AND FAR SOUTHERN NJ HAD RAIN TOTALS NEAR OR ABOVE 1 INCH YESTERDAY, LEADING TO HIGHER FUEL MOISTURES. FOR THE REST OF THE REGION HOWEVER, THE LIGHT RAIN YESTERDAY DID NOT HAVE MADE A SIGNIFICANT IMPACT ACROSS CENTRAL/NORTHERN NJ AND EASTERN PA ON FUEL MOISTURE AND DRYING OF THE FUEL MOISTURE WILL CONTINUE TODAY. AS FOR WINDS, GUSTS NEAR 20 KT ARE LIKELY ACROSS THE REGION. HOWEVER, THE TIGHTEST PRESSURE GRADIENT, AND THUS THE STRONGEST WINDS ARE EXPECTED IN THE MORNING BUT MAY LINGER INTO THE AFTERNOON. WE HAVE ISSUED A RED FLAG WARNING FOR EASTERN PA, NORTHERN/CENTRAL NJ UNTIL 7 PM DUE TO A COMBINATION OF LOW MOISTURE IN FINE FUELS, LOW RH 20% OR LOWER AND WIND GUSTS AROUND 25 MPH THROUGH THE AFTERNOON. FOR THURSDAY, THE RELATIVE HUMIDITY VALUES ARE FORECAST TO DROP TO 25-35 PERCENT IN THE AFTERNOON MAINLY FOR NEW JERSEY /AWAY FROM THE COAST/ AND EASTERN PENNSYLVANIA, HOWEVER THE WINDS ARE CURRENTLY FORECAST TO BE 15 MPH OR LESS. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR PAZ054-055- 060>062-070-071-101>106. NJ...RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR NJZ001- 007>010-012>015. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...GORSE NEAR TERM...GAINES/JOHNSON SHORT TERM...JOHNSON LONG TERM...GORSE AVIATION...GORSE/JOHNSON MARINE...GORSE/JOHNSON FIRE WEATHER...GAINES/JOHNSON
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
756 PM EDT THU APR 16 2015 .UPDATE... AREA OF RAIN CONTINUES TO BLOSSOM ACROSS THE CWFA THIS EVENING. LATEST RUNS OF THE HRRR SHOW THE RAINFALL SHOULD TAPER OFF AFTER 06Z. UPDATED THE POPS EARLIER THIS EVENING...AND JUST UPDATED THEM AGAIN TO CATEGORICAL OVER A GOOD PORTION OF THE CWFA. HAVE ALSO TWEAKED THE HOURLY TEMPS AND DEWPOINTS. CHANCES OF CONVECTION REMAIN SMALL...BUT SHOULD CONTINUE THROUGH MIDNIGHT. && .PREV DISCUSSION... /ISSUED 348 PM EDT THU APR 16 2015/ SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... A WET/UNSETTLED PATTERN LOOKS TO PERSIST THROUGH THE SHORT TERM. THE WEDGE PERSISTS THIS AFTERNOON AND SHOULD CONTINUE INTO THE OVERNIGHT WITH THE WEDGE GRADUALLY BREAKING DOWN FRIDAY. SHOWERS AND A FEW THUNDERSTORMS WERE INCREASING TO THE WEST AND SHOULD CONTINUE TO MOVE NORTHEAST...WITH HIGH RESOLUTION MODELS SHOWING WIDESPREAD RAINFALL FOR MUCH OF THE NIGHT. THIS SHOULD CONTINUE INTO FRIDAY MORNING. MOST UNSTABLE AIR WILL BE AROUND THE EDGE OF THE COOLER AIR AND HAVE INCLUDED THUNDER FOR TONIGHT ALONG THE NORTHERN AND WESTERN ZONES. SOME GENERAL INCREASE IN INSTABILITY FOR FRIDAY AND HAVE MENTIONED THUNDER ACROSS THE AREA. MODELS HINT AT A BREAK UNTIL NEXT WAVE APPROACHES THE FORECAST AREA ON SATURDAY...SO HAVE REDUCED THE POPS FOR FRIDAY NIGHT. FLOODING ISSUES MAY BE HIT AND MISS AND HAVE NOT ISSUED ANY FLOOD WATCH. SOME LOCAL RIVER AND STREET FLOODING WILL CONTINUE TO BE POSSIBLE. TEMPERATURES THIS AFTERNOON ARE RUNNING A BIT LOWER THAN FORECAST AND MAY HOLD NEAR STEADY OVERNIGHT WITH THE EASTERLY WINDS. SOME WARMING EXPECTED ON FRIDAY. 41 LONG TERM /SATURDAY THROUGH THURSDAY/... NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. MODELS STILL A BIT SLOWER WITH INCREASING DEEP MOISTURE ON SATURDAY WITH THE BEST MOISTURE NOT BEGINNING TO MOVE IN UNTIL 00Z SUN. BEST OPPORTUNITY FOR RAINFALL CONTINUES TO BE SUN/SUN NIGHT WITH HIGH SHOWERS CHANCES AND A CHANCE OF THUNDERSTORMS ACROSS THE AREA. PWS ACROSS THE AREA INCREASE INTO THE 1.5 TO 1.75 INCH RANGE BEGINNING 00Z SUN THROUGH 00Z MON. THIS WILL BRING PERIODS OF MODERATE TO HEAVY RAIN THIS WEEKEND ACROSS THE ENTIRE CWA. THE POTENTIAL FOR LOCALIZED FLOODING WILL NEED TO BE CLOSELY MONITORED. A COLD FRONT MOVES ACROSS THE AREA MONDAY/MONDAY NIGHT AND RAIN CHANCES WILL END MONDAY NIGHT. TUESDAY AND WEDNESDAY ARE EXPECTED TO BE DRY AS THE WESTERLY UPPER FLOW DRIES OUT. A SHORT WAVE IN THE UPPER FLOW THU MORNING WILL NEED TO BE WATCHED FOR POSSIBLE LIGHT PRECIP CHANCES. HAVE INTRODUCE A SLIGHT CHANCE OF PRECIP FOR NOW. TEMPERATURES ARE GENERALLY EXPECTED TO BE NEAR TO ABOVE NORMAL. 01 PREVIOUS LONG TERM DISCUSSION /FRIDAY NIGHT THROUGH WEDNESDAY/ /ISSUED AT 505 AM EDT THU APR 16 2015/...WE LOOK TO BE IN BETWEEN SYSTEMS FRIDAY NIGHT AS WEAK SURFACE HIGH PRESSURE AND A SHORT WAVE RIDGE ALOFT PREDOMINATE. THIS WILL TRANSLATE TO ONLY LOW POPS DURING THE EVENING FOR CENTRAL AND PARTS OF NORTH GEORGIA. FORECAST LOW TEMPERATURES RUNNING 8-10 DEGREES ABOVE NORMAL. MODELS NOW SLOWER WITH INCREASING DEEP MOISTURE ON SATURDAY IN THE SW UPPER FLOW AND INCREASING SOUTHERLY LOW LEVEL FLOW. BEST RAIN CHANCES NOW LOOK TO BE LATE SATURDAY AND LIGHT. DEEPEST MOISTURE INCREASES SATURDAY NIGHT AND CONTINUES INTO SUNDAY NIGHT WITH HIGH SHOWERS CHANCES AND A CHANCE OF THUNDERSTORMS ACROSS THE AREA. A COLD FRONT MOVES ACROSS THE AREA MONDAY/MONDAY NIGHT AND RAIN CHANCES WILL END MONDAY NIGHT. TUESDAY AND WEDNESDAY ARE EXPECTED TO BE DRY AS THE WESTERLY UPPER FLOW DRIES OUT. A SHORT WAVE IN THE UPPER FLOW LATE WEDNESDAY WILL NEED TO BE WATCHED FOR POSSIBLE LIGHT PRECIP CHANCES. UPDATED... AT THIS TIME...A PERIOD OF MODERATE TO HEAVY RAIN WILL BE POSSIBLE THIS WEEKEND...MOST SO FOR NORTHEAST GEORGIA. THE POTENTIAL FOR LOCALIZED FLOODING WILL NEED TO BE CLOSELY MONITORED. TEMPERATURES ARE GENERALLY EXPECTED TO BE NEAR TO ABOVE NORMAL. BDL && .AVIATION... 00Z UPDATE... AREA OF RAINFALL CONTINUES TO BLOSSOM ACROSS WEST GA THIS EVENING. VSBYS AND CIGS WILL REMAIN IMPACTED FOR MUCH OF THE NIGHT. LIFR CIGS POSSIBLE AFTER 06Z. SOME IMPROVEMENT IS LIKELY TOMORROW AFTERNOON. //ATL CONFIDENCE...00Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 54 72 58 81 / 90 40 20 40 ATLANTA 53 73 61 77 / 100 50 20 50 BLAIRSVILLE 52 71 54 75 / 100 40 20 40 CARTERSVILLE 53 73 57 79 / 100 50 20 50 COLUMBUS 57 73 61 79 / 100 60 20 50 GAINESVILLE 53 71 58 77 / 100 40 20 40 MACON 57 72 58 79 / 100 60 20 40 ROME 54 73 57 78 / 60 40 20 50 PEACHTREE CITY 53 73 57 77 / 100 50 20 50 VIDALIA 58 73 62 82 / 80 50 30 20 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
434 PM EDT WED APR 15 2015 .SYNOPSIS... A BACKDOOR COLD FRONT WILL GRADUALLY ADVANCE SOUTH ACROSS THE REGION THROUGH TONIGHT. A WEDGE OF HIGH PRESSURE WILL THEN DEVELOP AND STRENGTHEN INLAND ON THURSDAY AS AN AREA OF LOW PRESSURE FORMS OFF THE COAST. THE LOW WILL PUSH AWAY TO THE NORTHEAST THROUGH FRIDAY AS HIGH PRESSURE REMAINS INLAND THROUGH MUCH OF THE WEEKEND. THE NEXT STORM SYSTEM IS EXPECTED TO IMPACT THE AREA EARLY NEXT WEEK. HIGH PRESSURE WILL RETURN MID WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... THIS EVENING AND TONIGHT...SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE OVER PARTS OF THE AREA THIS EVENING AS A BACKDOOR COLD FRONT SLOWLY SHIFTS SOUTH THROUGH SOUTHEAST SOUTH CAROLINA. DEEP MOISTURE PROFILES CHARACTERIZED BY PWATS BETWEEN 1.4 TO 1.8 INCHES AND SFC DEWPTS IN THE UPPER 60S TO LOWER 70S RESIDE AHEAD OF THE FRONT. MODELS ARE IN GENERAL AGREEMENT THAT PRECIP WILL CONTINUE TO OCCUR AS A WEAK MID LVL WAVE SHIFTS OVER THE INTO EARLY EVENING HOURS...WITH THE NSSL WRF AND HRRR INDICATING SHOWER AND/OR THUNDERSTORM ACTIVITY SLOWLY PROGRESSING WEST TO EAST ACROSS A LARGE PART OF THE AREA INTO EARLY TONIGHT. LATEST RADAR SHOWS INTENSIFICATION OF A FEW THUNDERSTORMS AHEAD OF A BROKEN LINE OF LIGHT TO MODERATE SHOWERS CURRENTLY SHIFTING OVER INLAND PORTIONS OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA. SBCAPES NEAR 2000 J/KG ALONG WITH WEAK SHEAR AND POOR LAPSE RATES...INDICATE MAINLY PULSE/MULTI-CELL THUNDERSTORMS CAPABLE OF PRODUCING STRONG WINDS AND HEAVY RAINFALL AT TIMES. A FEW SEVERE THUNDERSTORMS ARE POSSIBLE THROUGH SUNSET THIS EVENING. AFTER SUNSET...SEVERE WEATHER POTENTIAL WILL BE LOW AS MOST INSTABILITY DECREASES DUE TO THE LOSS OF DAYTIME HEATING. THE BACKDOOR COLD FRONT SHOULD CONTINUE TO MOVE SOUTH IN SOUTHEAST GEORGIA OVERNIGHT...WITH SHOWERS AND PERHAPS AN ISOLATED THUNDERSTORM BEFORE MIDNIGHT. MOST PRECIP ACTIVITY SHOULD THEN SHIFT OFFSHORE LATE. TEMPS WILL COOL DOWN BEHIND THE FRONT...WITH LOWS RANGING IN THE MID 50S INLAND TO LOW/MID 60S IN SOUTHEAST GEORGIA. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... THURSDAY AND THURSDAY NIGHT...THE MORNING WILL BEGIN WITH A WELL DEFINED INLAND WEDGE OF HIGH PRESSURE AND A SHARPENING COASTAL TROUGH/LOW JUST OFFSHORE. THIS PATTERN WILL GENERALLY REMAIN IN PLACE THROUGH THE DAY WITH THE OFFSHORE LOW SLOWLY MOVING TO THE NORTHEAST. THE MAIN CHANGE IN THIS POST-FRONTAL AIRMASS WILL BE THE SUBSTANTIALLY LOWER RAIN CHANCES THANKS TO THE PRONOUNCED MID LEVEL DRYING NOTED IN MODEL SOUNDINGS AND TIME HEIGHTS. IN FACT...MOST MODEL SOLUTIONS ARE COMPLETELY DRY BUT WE HAVE MAINTAINED A SLIGHT CHANCE IN MOST PLACES TO ACCOUNT FOR THE PLENTIFUL LOW LEVEL MOISTURE. REGARDLESS...IT SHOULD BE A MUCH QUIETER DAY THAN THE LAST FEW. WITHIN THE WEDGE AND OVERCAST SKIES...TEMPERATURES WILL BE COOLER WITH HIGHS IN THE MID 60S INLAND RANGING TO UPPER 60S AND LOW 70S ALONG THE COAST AND ESPECIALLY SOUTHEAST GEORGIA. OVERNIGHT...VERY LITTLE CHANGE IN THE FORECAST THINKING. HIGH PRESSURE WILL REMAIN THE PRIMARY FEATURE AND WITH MUCH DRIER AIR IN THE MID LEVELS OVERALL RAIN CHANCES WILL REMAIN QUITE LOW. OVERNIGHT LOWS WILL ONLY FALL INTO THE UPPER 50S TO LOW 60S. FRIDAY THROUGH SATURDAY...THE FORECAST CONTINUES TO LOOK LESS ACTIVE THROUGH THE FIRST HALF OF THE WEEKEND AS HIGH PRESSURE SITS INLAND AHEAD OF THE NEXT SYSTEM THAT STARTS TO WRAP UP ACROSS THE MID AND LOWER MISSISSIPPI VALLEY. RIDGING ALOFT WILL ALSO BUILD AND MOVE ACROSS THE SOUTHEAST THROUGH SATURDAY. RAIN CHANCES REMAIN IN THE SLIGHT CHANCE TO CHANCE RANGE AND MAY NEED TO BE LOWERED FURTHER IF MODEL TRENDS CONTINUE. TEMPERATURES WILL CONTINUE TO WARM...INTO THE MID/UPPER 70S FOR FRIDAY AND THEN LOW 80S FOR SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... MODELS HAVE COME INTO A BIT BETTER AGREEMENT IN THE LONG TERM PERIOD. ON SUNDAY...AN AREA OF LOW PRESSURE WILL BE MOVING NORTHEAST INTO THE GREAT LAKES REGION. THE LOW WILL PROGRESS EAST AND SEND A TRAILING COLD FRONT THROUGH THE AREA MONDAY NIGHT INTO TUESDAY. SHOWERS/THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF AND ALONG THE FRONT. QUIET WEATHER WILL RETURN MID WEEK AS HIGH PRESSURE BUILDS INTO THE REGION. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... KCHS...A BACKDOOR COLD FRONT SHOULD SHIFT OVER THE TERMINAL SOMETIME BETWEEN 18Z AND 20Z...WITH MVFR CIGS LIKELY THROUGH THE AFTERNOON AND EVENING HOURS. SHOWERS AND/OR THUNDERSTORMS ARE ALSO POSSIBLE IN THE VICINITY THE TERMINAL THIS AFTERNOON AND COULD CAUSE VSBY REDUCTIONS. IFR CIGS WILL BE POSSIBLE LATE AFTERNOON...BUT CONFIDENCE IN STARTING TIME OF EVENT IS TOO LOW TO INCLUDE EARLIER THAN 03Z TONIGHT. PREVAILING IFR CONDITIONS ARE EXPECTED OVERNIGHT AND INTO EARLY THURSDAY MORNING...BEFORE GRADUALLY IMPROVING TO MVFR DURING THE AFTERNOON. KSAV...VFR CONDITIONS ARE EXPECTED INTO THE AFTERNOON BUT SHOWERS AND/OR THUNDERSTORMS COULD LOWER CIGS/VSBYS TO MVFR BY EARLY EVENING. LOWER CIGS SHOULD THEN MOVE OVER THE TERMINAL TONIGHT AS A BACKDOOR COLD FRONT APPROACHES THE TERMINAL. IFR CIGS APPEAR LIKELY BEHIND THE FRONT LATE TONIGHT AND INTO THURSDAY MORNING. CIGS SHOULD GRADUALLY IMPROVE TO MVFR LEVELS THURSDAY AFTERNOON. EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CONDITIONS WILL LIKELY CONTINUE THROUGH THURSDAY AFTERNOON AND THEN THURSDAY NIGHT IN FOG/STRATUS. CONDITIONS WILL IMPROVE THROUGH THE DAY ON FRIDAY AND VFR WILL LIKELY PREVAIL THEREAFTER. && .MARINE... TONIGHT...A BACKDOOR FRONT WILL SLOWLY MOVE SOUTH THROUGH THE WATERS...CAUSING A SURGE OF WINDS AND SEAS BEHIND IT AS HIGH PRESSURE BUILDS FROM THE NORTH. LATEST OBS AND PILOT BOAT REPORTS INDICATE STRONG WINDS BEHIND THE FRONT...THUS A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE CHS HARBOR UNTIL 11 PM TONIGHT. A SMALL CRAFT ADVISORY ALSO REMAINS IN EFFECT FOR NORTHERN SC WATERS OFF THE CHARLESTON COAST...BUT GIVEN LATEST TRENDS HAVE INITIATED WITH SMALL CRAFT ADVISORY CONDITIONS AT 8 PM. NORTHEAST FLOW WILL CONTINUE TO STRENGTHEN BEHIND THE BACKDOOR COLD FRONT LATE TONIGHT WITH WIND GUSTS AS HIGH AS 25-30 KTS OFF THE CHARLESTON COUNTY COAST. SEAS WILL ALSO BUILD FROM 2 FT TO 4-6 FT EAST AND NORTHEAST OF CHARLESTON AFTER MIDNIGHT. GEORGIA WATERS WILL SEE A MUCH SLOWER PROGRESSION OF BUILDING SEAS AND WINDS SHOULD STAY BELOW ADVISORY LEVEL CRITERIA THROUGH TONIGHT. THURSDAY THROUGH MONDAY...CONDITIONS ACROSS THE LOCAL WATERS WILL BE AT THEIR WORST ON THURSDAY THANKS TO A PINCHED NORTH TO NORTHEAST GRADIENT BETWEEN INLAND HIGH PRESSURE AND A DEVELOPING COASTAL LOW. WINDS/SEAS WILL SUPPORT SMALL CRAFT ADVISORIES FOR THE CHARLESTON COUNTY WATERS AND THE OUTER GEORGIA WATERS THROUGH THE DAY AND INTO THE OVERNIGHT. ELSEWHERE...WINDS WILL BE 15-20 KT WITH ELEVATED SEAS AS WELL. THE GRADIENT WILL BEGIN TO RELAX THURSDAY NIGHT AND ESPECIALLY BY FRIDAY MORNING AS THE SURFACE LOW PULLS AWAY TO THE NORTHEAST. THEN A MORE UNIFORM SOUTHERLY FLOW REGIME WILL RETURN THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK AHEAD OF THE NEXT SERIES OF SURFACE LOWS THAT PASS NORTHWEST OF THE AREA. RIP CURRENTS...HAVE COME UP WITH A MODERATE RISK FOR THE CHARLESTON COUNTY BEACHES FOR THURSDAY BASED ON STRONG NORTHEAST TO NORTH- NORTHEAST WINDS AND CONSIDERABLE WAVE ACTION. SIMILAR CONDITIONS ALONG THE REST OF THE SOUTH CAROLINA COAST THOUGH WINDS WILL BE A BIT WEAKER THE FURTHER SOUTH YOU GO SO LOW RISK IS IN PLACE ELSEWHERE. THE ELEVATED RISK FOR RIP CURRENTS WILL PERSIST THROUGH THE WEEKEND AS ASTRONOMICAL FACTORS INCREASE. && .TIDES/COASTAL FLOODING... A COMBINATION OF ASTRONOMICAL HIGH TIDES AND LINGERING NORTHEAST WINDS/SWELL WILL RESULT IN A THREAT FOR SHALLOW COASTAL FLOODING NEAR THE TIME OF HIGH TIDE THURSDAY AND FRIDAY EVENING...PERHAPS EXTENDING INTO THE SATURDAY EVENING HIGH TIDE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ330. SMALL CRAFT ADVISORY FROM 8 AM THURSDAY TO 2 PM EDT FRIDAY FOR AMZ374. SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 2 AM EDT FRIDAY FOR AMZ350. && $$ SYNOPSIS... NEAR TERM...DPB SHORT TERM...BSH LONG TERM...ECT AVIATION...BSH/DPB MARINE...BSH/DPB TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
148 PM EDT WED APR 15 2015 .SYNOPSIS... A BACKDOOR COLD FRONT WILL GRADUALLY ADVANCE SOUTH ACROSS THE REGION THROUGH TONIGHT. A WEDGE OF HIGH PRESSURE WILL DEVELOP BEHIND THE FRONT AND WILL STRENGTHEN THURSDAY AS A COASTAL TROUGH DEVELOPS OFFSHORE. THE TROUGH WILL LIFT NORTHEAST UP THE COAST FRIDAY...WITH WEAK HIGH PRESSURE DEVELOPING IN ITS WAKE. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE AREA EARLY NEXT WEEK. HIGH PRESSURE WILL RETURN MID WEEK. && .NEAR TERM /THROUGH TONIGHT/... THIS AFTERNOON...A BACKDOOR COLD FRONT CURRENTLY OVER THE TRI COUNTY AREA WILL GRADUALLY SHIFT SOUTHWARD THROUGH TONIGHT. DEEP MOISTURE PROFILES CHARACTERIZED BY PWATS BETWEEN 1.4 TO 1.8 INCHES AND SFC DEWPTS IN THE UPPER 60S TO LOWER 70S RESIDE AHEAD OF THE FRONT. MODELS ARE IN GENERAL AGREEMENT THAT THE BULK OF PRECIP WILL OCCUR AS AN H5 SHORTWAVE SHIFTS OVER THE AREA THIS AFTERNOON INTO EARLY EVENING HOURS...WITH THE NSSL WRF AND HRRR INDICATING A LINE OF SHOWER AND/OR THUNDERSTORM ACTIVITY SLOWLY PROGRESSING WEST TO EAST ACROSS A LARGE PART OF THE AREA. LATEST RADAR SHOWS A LINE OF SHOWERS WITH ISOLATED THUNDERSTORMS SHIFTING OVER THE MIDLANDS AND TOWARD INLAND COUNTIES OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA. EXPECT SOME INTENSIFICATION OF THIS LINE AS IT ENCOUNTERS LOCATIONS THAT HAVE SEEN SUN TODAY. SBCAPES NEAR 3000 J/KG ALONG WITH WEAK SHEAR AND POOR LAPSE RATES...INDICATE MAINLY PULSE/MULTI-CELL THUNDERSTORMS OVER THE AREA...WITH THE GREATER RISK IN SOUTHEAST GEORGIA AND FOR LOCATIONS WEST OF I-95 IN SOUTHEAST SOUTH CAROLINA. SHOWERS AND THUNDERSTORMS COULD ALSO DEVELOP AHEAD OF THIS LINE...WHERE LFC AND LCL LEVELS INDICATE INITIATION. A FEW OF THESE STORMS COULD BE STRONG...WITH DAMAGING WIND GUSTS BEING THE PRIMARY CONCERN THIS AFTERNOON AND EVENING. ANOTHER AREA OF THUNDERSTORM ENHANCEMENT SHOULD OCCUR LATER THIS AFTERNOON AS ACTIVITY ENCOUNTERS THE SOUTHWARD MOVING BACKDOOR COLD FRONT. IN ADDITION TO DAMAGING WINDS...LOCAL HEAVY RAINFALL IS POSSIBLE. OVERALL HIGH TEMPS HAVE BEEN ADJUSTED UP 1-2 DEGREES SOUTH OF THE BACKDOOR COLD FRONT THIS AFTERNOON. IN GENERAL...HIGH TEMPS SHOULD RANGE IN THE MID 80S IN SOUTHEAST GEORGIA AND MID/UPPER 70S SOUTH OF THE FRONT IN SOUTHEAST SOUTH CAROLINA. TONIGHT...THE FRONT SHOULD CONTINUE TO MOVE SOUTH AND MODELS INDICATE MID LEVEL OMEGA...UPPER LEVEL DIVERGENCE INTO THE EVENING HOURS. LOW LEVEL CONVERGENCE SHOULD ALSO REMAIN DECENT ALONG THE FRONT. INSTABILITY SHOULD TAP OUT EARLY IN THE EVENING AND WE TRENDED LIKELY POPS TOWARD CHANCE POPS AFTER MIDNIGHT. SLIGHTLY COOLER AIR WILL BE NOTED ACROSS THE REGION AS A SURFACE WEDGE STRENGTHENS. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... THURSDAY...A WEDGE OF HIGH PRESSURE WILL PERSIST INLAND AND STRENGTHEN AS A COASTAL TROUGH REMAINS OFFSHORE. DIFFERENCES EXIST AMONG MODEL SOLUTIONS WITH THE EVOLUTION OF THESE FEATURES THROUGH THE DAY WITH THE NAM LIFTING THE TROUGH NORTHEAST AND EURO/GFS FAVORING A NEARLY STATIONARY TROUGH. HAVE LEANED TOWARDS THE LATTER...WITH THE WEDGE REMAINING IN PLACE. DEEPEST MOISTURE AND BEST FORCING WILL REMAIN OUT OF THE MAJORITY OF THE AREA...SO HAVE TRENDED POPS DOWN QUITE A BIT. CURRENT POP SCHEME FEATURES 30-40 PERCENT CHANCE POPS. POOR THERMODYNAMICS WILL KEEP SEVERE THREAT NEAR ZERO. CLOUDY SKIES AND COOL NORTHEAST FLOW WILL KEEP TEMPERATURES BELOW NORMAL. HIGHS WILL RANGE FROM THE MID/UPPER 60S NORTHWEST...TO MID 70S ACROSS THE SOUTHEAST. OVERNIGHT...THE COASTAL TROUGH WILL SLOWLY LIFT NORTHEAST ALLOWING THE INLAND WEDGE OF HIGH PRESSURE TO WEAKEN. LOWS WILL BE IN THE UPPER 50S/LOW 60S. FRIDAY...THE WEDGE WILL ERODE AND THE PRESSURE PATTERN WILL BECOME RATHER ILL-DEFINED WITH WEAK HIGH PRESSURE TO PREVAIL. WEAK SHORTWAVE ENERGY AND MARGINAL MOISTURE WILL KEEP POPS LIMITED TO AROUND 30 PERCENT. TEMPERATURES WILL MODERATE CLOSER TO NORMAL WITH HIGHS IN THE MID/UPPER 70S. FRIDAY NIGHT...FAIRLY QUIET WEATHER WILL BE ON TAP WITH LOWS MAINLY IN THE LOW 60S. SATURDAY...HIGH PRESSURE WILL PREVAIL AHEAD OF THE NEXT STORM SYSTEM DEVELOPING OVER THE SOUTHERN PLAINS. ALOFT...WEAK RIDGING WILL TAKE PLACE WHILE A CUT OFF LOW DEEPENS OVER THE MIDWEST. INCREASING MOISTURE AND SHORTWAVE ENERGY EJECTING OUT OF THE SOUTHWEST FLOW WILL RESULT IN INCREASING CHANCES FOR SHOWERS/ISOLATED THUNDERSTORMS...WITH THE BEST CHANCES BEING IN OUR SOUTHWEST ZONES. LOW LEVEL THICKNESS PROGS SUPPORT HIGHS IN THE UPPER 70S/LOW 80S. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... MODELS HAVE COME INTO A BIT BETTER AGREEMENT IN THE LONG TERM PERIOD. ON SUNDAY...AN AREA OF LOW PRESSURE WILL BE MOVING NORTHEAST INTO THE GREAT LAKES REGION. THE LOW WILL PROGRESS EAST AND SEND A TRAILING COLD FRONT THROUGH THE AREA MONDAY NIGHT INTO TUESDAY. SHOWERS/THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF AND ALONG THE FRONT. QUIET WEATHER WILL RETURN MID WEEK AS HIGH PRESSURE BUILDS INTO THE REGION. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... KCHS...A BACKDOOR COLD FRONT SHOULD SHIFT OVER THE TERMINAL SOMETIME BETWEEN 18Z AND 20Z...WITH MVFR CIGS LIKELY THROUGH THE AFTERNOON AND EVENING HOURS. SHOWERS AND/OR THUNDERSTORMS ARE ALSO POSSIBLE IN THE VICINITY THE TERMINAL THIS AFTERNOON AND COULD CAUSE VSBY REDUCTIONS. IFR CIGS WILL BE POSSIBLE LATE AFTERNOON...BUT CONFIDENCE IN STARTING TIME OF EVENT IS TOO LOW TO INCLUDE EARLIER THAN 03Z TONIGHT. PREVAILING IFR CONDITIONS ARE EXPECTED OVERNIGHT AND INTO EARLY THURSDAY MORNING...BEFORE GRADUALLY IMPROVING TO MVFR DURING THE AFTERNOON. KSAV...VFR CONDITIONS ARE EXPECTED INTO THE AFTERNOON BUT SHOWERS AND/OR THUNDERSTORMS COULD LOWER CIGS/VSBYS TO MVFR BY EARLY EVENING. LOWER CIGS SHOULD THEN MOVE OVER THE TERMINAL TONIGHT AS A BACKDOOR COLD FRONT APPROACHES THE TERMINAL. IFR CIGS APPEAR LIKELY BEHIND THE FRONT LATE TONIGHT AND INTO THURSDAY MORNING. CIGS SHOULD GRADUALLY IMPROVE TO MVFR LEVELS THURSDAY AFTERNOON. EXTENDED AVIATION OUTLOOK...MVFR/IFR CIGS LIKELY INTO AT LEAST FRIDAY MORNING AS A WEDGE OF HIGH PRESSURE PERSISTS INLAND. VFR EXPECTED THROUGH MUCH OF THE WEEKEND OUTSIDE OF SHOWERS/TSTORMS. && .MARINE... A BACKDOOR FRONT WILL SLOWLY MOVE SOUTH THROUGH THE WATERS THIS AFTERNOON AND TONIGHT. THUNDERSTORMS WILL BE THE MAIN RISK FOR MARINERS THIS AFTERNOON...BEFORE THE PRESSURE GRADIENT BEGINS TO PINCH LATER THIS AFTERNOON AND TONIGHT ALONG THE CENTRAL SOUTH CAROLINA COAST. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR CHARLESTON WATERS STARTING EARLY TONIGHT AS NORTHEAST FLOW STRENGTHENS BEHIND THE FRONT. SEAS WILL ALSO BUILD FROM 2 FT TO 4-6 FT EAST AND NORTHEAST OF CHARLESTON AFTER MIDNIGHT. GEORGIA WATERS WILL SEE A MUCH SLOWER PROGRESSION OF BUILDING SEAS AND WINDS SHOULD STAY BELOW ADVISORY LEVEL CRITERIA THROUGH TONIGHT. THURSDAY THROUGH MONDAY...A WEDGE OF HIGH PRESSURE WILL BE SITUATED INLAND WITH A COASTAL TROUGH OFFSHORE. A TIGHTENED PRESSURE GRADIENT WILL RESULT IN INCREASED WINDS/SEAS ESPECIALLY ACROSS OUR NORTHERN ZONES. ONGOING SMALL CRAFT ADVISORY IN THE CHARLESTON COUNTY WATERS WILL CONTINUE THROUGH MUCH OF THE DAY AS SEAS REMAIN 4-6 FEET. AN ADVISORY MAY EVENTUALLY BE NEEDED IN THE OUTER GA WATERS AS WELL HOWEVER THERE ARE SOME MODEL DISCREPANCIES ON WHERE THE COASTAL TROUGH WILL SET UP SO HAVE OPTED TO HOLD OFF FOR NOW. ON FRIDAY...THE WEDGE WILL BEGIN TO ERODE AND THE PRESSURE GRADIENT WILL RELAX. HIGH PRESSURE WILL PREVAIL INTO EARLY WEEKEND AHEAD OF THE NEXT LOW PRESSURE SYSTEM WHICH WILL IMPACT THE WATERS EARLY NEXT WEEK. AT THIS TIME...WINDS/SEAS ARE EXPECTED TO REMAIN UNDER HEADLINE CRITERIA. RIP CURRENTS...STRENGTHENING NORTHEAST WINDS AND BUILDING WAVES THURSDAY COULD PRODUCE AN ENHANCED RISK OF RIP CURRENTS INTO FRIDAY. && .TIDES/COASTAL FLOODING... A COMBINATION OF ASTRONOMICAL HIGH TIDES AND LEFTOVER NORTHEAST WINDS/SWELL WILL RESULT IN A THREAT FOR SHALLOW COASTAL FLOODING NEAR THE TIME OF HIGH TIDE THURSDAY AND FRIDAY EVENING...PERHAPS EXTENDING INTO THE SATURDAY EVENING HIGH TIDE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 8 PM EDT THURSDAY FOR AMZ350. && $$ SYNOPSIS... NEAR TERM...DPB SHORT TERM...ECT LONG TERM...ECT AVIATION...DPB MARINE...DPB/ECT TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1259 PM EDT WED APR 15 2015 .SYNOPSIS... A BACKDOOR COLD FRONT WILL GRADUALLY ADVANCE SOUTH ACROSS THE REGION THROUGH TONIGHT. A WEDGE OF HIGH PRESSURE WILL DEVELOP BEHIND THE FRONT AND WILL STRENGTHEN THURSDAY AS A COASTAL TROUGH DEVELOPS OFFSHORE. THE TROUGH WILL LIFT NORTHEAST UP THE COAST FRIDAY...WITH WEAK HIGH PRESSURE DEVELOPING IN ITS WAKE. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE AREA EARLY NEXT WEEK. HIGH PRESSURE WILL RETURN MID WEEK. && .NEAR TERM /THROUGH TONIGHT/... THIS AFTERNOON...A BACKDOOR COLD FRONT CURRENTLY OVER THE TRI COUNTY AREA WILL GRADUALLY SHIFT SOUTHWARD THROUGH TONIGHT. DEEP MOISTURE PROFILES CHARACTERIZED BY PWATS BETWEEN 1.4 TO 1.8 INCHES AND SFC DEWPTS IN THE UPPER 60S TO LOWER 70S RESIDE AHEAD OF THE FRONT...SUPPORTING AN ENVIRONMENT CAPABLE OF LOCALLY HEAVY RAINFALL. MODELS ARE IN GENERAL AGREEMENT THAT THE BULK OF PRECIP WILL OCCUR AS AN H5 SHORTWAVE SHIFTS OVER THE AREA THIS AFTERNOON INTO EARLY EVENING HOURS...WITH THE NSSL WRF AND HRRR INDICATING A LINE OF SHOWER AND/OR THUNDERSTORM ACTIVITY SLOWLY PROGRESSING WEST TO EAST ACROSS A LARGE PART OF THE AREA. LATEST RADAR SHOWS A LINE OF SHOWERS WITH ISOLATED THUNDERSTORMS SHIFTING OVER THE MIDLANDS AND TOWARD INLAND COUNTIES OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA. EXPECT SOME INTENSIFICATION OF THIS LINE AS IT ENCOUNTERS LOCATIONS THAT HAVE SEEN SUN TODAY. SBCAPES NEAR 3000 J/KG ALONG WITH WEAK SHEAR AND POOR LAPSE RATES...INDICATE MAINLY PULSE/MULTI-CELL THUNDERSTORMS OVER THE AREA...WITH THE GREATER RISK IN SOUTHEAST GEORGIA. SHOWERS AND THUNDERSTORMS COULD ALSO DEVELOP AHEAD OF THIS LINE...WHERE LFC AND LCL LEVELS INDICATE POSSIBLE INITIATION. A FEW OF THESE STORMS COULD BE STRONG...WITH DAMAGING WIND GUSTS BEING THE PRIMARY CONCERN THIS AFTERNOON AND EVENING. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE AS THE MAIN LINE OF ACTIVITY SHIFTS OVER THE AREA INTO THE EVENING. OVERALL HIGH TEMPS HAVE BEEN ADJUSTED UP 1-2 DEGREES SOUTH OF THE BACKDOOR COLD FRONT THIS AFTERNOON. IN GENERAL...HIGH TEMPS SHOULD RANGE IN THE MID 80S IN SOUTHEAST GEORGIA AND MID/UPPER 70S SOUTH OF THE FRONT IN SOUTHEAST SOUTH CAROLINA. TONIGHT...THE FRONT SHOULD CONTINUE TO MOVE SOUTH AND MODELS INDICATE MID LEVEL OMEGA...UPPER LEVEL DIVERGENCE INTO THE EVENING HOURS. LOW LEVEL CONVERGENCE SHOULD ALSO REMAIN DECENT ALONG THE FRONT. INSTABILITY SHOULD TAP OUT EARLY IN THE EVENING AND WE TRENDED LIKELY POPS TOWARD CHANCE POPS AFTER MIDNIGHT. SLIGHTLY COOLER AIR WILL BE NOTED ACROSS THE REGION AS A SURFACE WEDGE STRENGTHENS. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... THURSDAY...A WEDGE OF HIGH PRESSURE WILL PERSIST INLAND AND STRENGTHEN AS A COASTAL TROUGH REMAINS OFFSHORE. DIFFERENCES EXIST AMONG MODEL SOLUTIONS WITH THE EVOLUTION OF THESE FEATURES THROUGH THE DAY WITH THE NAM LIFTING THE TROUGH NORTHEAST AND EURO/GFS FAVORING A NEARLY STATIONARY TROUGH. HAVE LEANED TOWARDS THE LATTER...WITH THE WEDGE REMAINING IN PLACE. DEEPEST MOISTURE AND BEST FORCING WILL REMAIN OUT OF THE MAJORITY OF THE AREA...SO HAVE TRENDED POPS DOWN QUITE A BIT. CURRENT POP SCHEME FEATURES 30-40 PERCENT CHANCE POPS. POOR THERMODYNAMICS WILL KEEP SEVERE THREAT NEAR ZERO. CLOUDY SKIES AND COOL NORTHEAST FLOW WILL KEEP TEMPERATURES BELOW NORMAL. HIGHS WILL RANGE FROM THE MID/UPPER 60S NORTHWEST...TO MID 70S ACROSS THE SOUTHEAST. OVERNIGHT...THE COASTAL TROUGH WILL SLOWLY LIFT NORTHEAST ALLOWING THE INLAND WEDGE OF HIGH PRESSURE TO WEAKEN. LOWS WILL BE IN THE UPPER 50S/LOW 60S. FRIDAY...THE WEDGE WILL ERODE AND THE PRESSURE PATTERN WILL BECOME RATHER ILL-DEFINED WITH WEAK HIGH PRESSURE TO PREVAIL. WEAK SHORTWAVE ENERGY AND MARGINAL MOISTURE WILL KEEP POPS LIMITED TO AROUND 30 PERCENT. TEMPERATURES WILL MODERATE CLOSER TO NORMAL WITH HIGHS IN THE MID/UPPER 70S. FRIDAY NIGHT...FAIRLY QUIET WEATHER WILL BE ON TAP WITH LOWS MAINLY IN THE LOW 60S. SATURDAY...HIGH PRESSURE WILL PREVAIL AHEAD OF THE NEXT STORM SYSTEM DEVELOPING OVER THE SOUTHERN PLAINS. ALOFT...WEAK RIDGING WILL TAKE PLACE WHILE A CUT OFF LOW DEEPENS OVER THE MIDWEST. INCREASING MOISTURE AND SHORTWAVE ENERGY EJECTING OUT OF THE SOUTHWEST FLOW WILL RESULT IN INCREASING CHANCES FOR SHOWERS/ISOLATED THUNDERSTORMS...WITH THE BEST CHANCES BEING IN OUR SOUTHWEST ZONES. LOW LEVEL THICKNESS PROGS SUPPORT HIGHS IN THE UPPER 70S/LOW 80S. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... MODELS HAVE COME INTO A BIT BETTER AGREEMENT IN THE LONG TERM PERIOD. ON SUNDAY...AN AREA OF LOW PRESSURE WILL BE MOVING NORTHEAST INTO THE GREAT LAKES REGION. THE LOW WILL PROGRESS EAST AND SEND A TRAILING COLD FRONT THROUGH THE AREA MONDAY NIGHT INTO TUESDAY. SHOWERS/THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF AND ALONG THE FRONT. QUIET WEATHER WILL RETURN MID WEEK AS HIGH PRESSURE BUILDS INTO THE REGION. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... KCHS...A COLD FRONT EXTENDED FROM ABOUT MANNING TO GEORGETOWN SHOULD SHIFT OVER THE TERMINAL SOMETIME BETWEEN 16Z AND 19Z BUT SIGNIFICANT WIND SHIFTS ARE NOT EXPECTED. SHOWERS AND/OR THUNDERSTORMS ARE POSSIBLE IN THE VICINITY THIS AFTERNOON BUT TIMING AND INITIAL COVERAGE OF CONVECTION IS UNCERTAIN. CIGS SHOULD LOWER TO MVFR OR IFR LATER TODAY AND LIKELY BE REDUCED TO IFR LATER TONIGHT IN A SURGE WEDGE PATTERN WITH A LARGE LOW LEVEL INVERSION. KSAV...VFR CONDITIONS ARE EXPECTED INTO THE AFTERNOON BUT SCATTERED TO NUMEROUS CONVECTION COULD LOCALLY LOWER CIGS/VSBYS TO MVFR BY EARLY EVENING. AS THE SURFACE WEDGE STRENGTHENS TONIGHT... LOWER CLOUDS WILL EXPAND UNDER THE INVERSION AND IFR CIGS APPEAR TO BE A GOOD BET...BUT TIMING PRIOR TO 12Z THURSDAY IS UNCERTAIN. EXTENDED AVIATION OUTLOOK...MVFR/IFR CIGS LIKELY INTO AT LEAST FRIDAY MORNING AS A WEDGE OF HIGH PRESSURE PERSISTS INLAND. VFR EXPECTED THROUGH MUCH OF THE WEEKEND OUTSIDE OF SHOWERS/TSTORMS. && .MARINE... A BACKDOOR FRONT WILL SLOWLY MOVE SOUTH THROUGH THE WATERS THIS AFTERNOON AND TONIGHT. THUNDERSTORMS WILL BE THE MAIN RISK FOR MARINERS THIS AFTERNOON...BEFORE THE PRESSURE GRADIENT BEGINS TO PINCH LATER THIS AFTERNOON AND TONIGHT ALONG THE CENTRAL SOUTH CAROLINA COAST. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR CHARLESTON WATERS STARTING EARLY TONIGHT AS NORTHEAST FLOW STRENGTHENS BEHIND THE FRONT. SEAS WILL ALSO BUILD FROM 2 FT TO 4-6 FT EAST AND NORTHEAST OF CHARLESTON AFTER MIDNIGHT. GEORGIA WATERS WILL SEE A MUCH SLOWER PROGRESSION OF BUILDING SEAS AND WINDS SHOULD STAY BELOW ADVISORY LEVEL CRITERIA THROUGH TONIGHT. THURSDAY THROUGH MONDAY...A WEDGE OF HIGH PRESSURE WILL BE SITUATED INLAND WITH A COASTAL TROUGH OFFSHORE. A TIGHTENED PRESSURE GRADIENT WILL RESULT IN INCREASED WINDS/SEAS ESPECIALLY ACROSS OUR NORTHERN ZONES. ONGOING SMALL CRAFT ADVISORY IN THE CHARLESTON COUNTY WATERS WILL CONTINUE THROUGH MUCH OF THE DAY AS SEAS REMAIN 4-6 FEET. AN ADVISORY MAY EVENTUALLY BE NEEDED IN THE OUTER GA WATERS AS WELL HOWEVER THERE ARE SOME MODEL DISCREPANCIES ON WHERE THE COASTAL TROUGH WILL SET UP SO HAVE OPTED TO HOLD OFF FOR NOW. ON FRIDAY...THE WEDGE WILL BEGIN TO ERODE AND THE PRESSURE GRADIENT WILL RELAX. HIGH PRESSURE WILL PREVAIL INTO EARLY WEEKEND AHEAD OF THE NEXT LOW PRESSURE SYSTEM WHICH WILL IMPACT THE WATERS EARLY NEXT WEEK. AT THIS TIME...WINDS/SEAS ARE EXPECTED TO REMAIN UNDER HEADLINE CRITERIA. RIP CURRENTS...STRENGTHENING NORTHEAST WINDS AND BUILDING WAVES THURSDAY COULD PRODUCE AN ENHANCED RISK OF RIP CURRENTS INTO FRIDAY. && .TIDES/COASTAL FLOODING... A COMBINATION OF ASTRONOMICAL HIGH TIDES AND LEFTOVER NORTHEAST WINDS/SWELL WILL RESULT IN A THREAT FOR SHALLOW COASTAL FLOODING NEAR THE TIME OF HIGH TIDE THURSDAY AND FRIDAY EVENING...PERHAPS EXTENDING INTO THE SATURDAY EVENING HIGH TIDE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 8 PM EDT THURSDAY FOR AMZ350. && $$ SYNOPSIS... NEAR TERM...DPB SHORT TERM...ECT LONG TERM...ECT AVIATION...DPB MARINE...DPB/ECT TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS LINCOLN IL
901 PM CDT THU APR 16 2015 .UPDATE... ISSUED AT 901 PM CDT THU APR 16 2015 HIGH PRESSURE OVER THE REGION WILL RESULT IN MINIMAL CLOUD COVER OVERNIGHT. HOWEVER...FAIRLY HIGH DEWPOINTS MAINLY IN THE 50S WILL LIKELY PRODUCE AREAS OF FOG AS THE CLEAR SKIES ALLOW GOOD RADIATIONAL COOLING ALONG WITH LIGHT WINDS ASSOCIATED WITH THE HIGH. ALREADY HAVE AREAS OF FOG IN FORECAST FROM I-57 CORRIDOR EASTWARD...WHICH IS IN GOOD AGREEMENT WITH THE LATEST HRRR MODEL. MAIN UPDATE POSSIBILITY WOULD BE EXTENT OF FOG WESTWARD...AS WELL AS IF ANY DENSE AREAS DEVELOP. FOR NOW...CURRENT FORECAST LOOKS IN GOOD SHAPE WITH ONLY UPDATES FOR MINOR TEMPERATURE/CLOUD TRENDS SO FAR. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 310 PM CDT THU APR 16 2015 HIGH PRESSURE RIDGE SLIDING OFF TO THE EAST AS QUASI ZONAL FLOW TRANSITIONING TO A SLIGHTLY SOUTHWESTERLY FLOW WITH A DEEP LOW DIGGING IN AT H5 OVER THE DESERT SW. REMNANT MOISTURE AFFILIATED WITH WAVE PULLING OFF TO THE EAST STILL IMPACTING THE EASTERN EDGES OF THE STATE THIS AFTERNOON WITH A MORE PERSISTENT CLOUD COVER. LIGHT AND VARIABLE WINDS TONIGHT WITH CLEARING SKIES JUST BEFORE SUNSET SHOULD SET UP A GOOD ENVIRONMENT FOR SOME RADIATIONAL COOLING. WITH RELATIVELY HIGHER RH IN THE BOUNDARY LAYER TODAY NOT GETTING MUCH OF A CHANCE FOR MIXING...HAVE PUT FOG IN FOR THE OVERNIGHT IN THE EAST AND SOUTHEAST. CONCERN THAT IT MAY BE MORE WIDESPREAD THAN THE CURRENT PLACEMENT WITH THE DWPTS IN THE WEST STILL NEAR 50. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 310 PM CDT THU APR 16 2015 FRIDAY WILL FEATURE UPPER LEVEL RIDGING AND WARMING ACROSS ILLINOIS, AS A CUT-OFF LOW IN THE PLAINS SLOWLY DRIFTS FROM THE FOUR CORNERS INTO COLORADO. HIGHS WILL REACH INTO THE UPPER 70S IN MANY AREAS FRIDAY AFTERNOON, UNDER A LIGHT SOUTHEAST WIND. RAIN AHEAD OF THE CUT-OFF LOW WILL ADVANCE EASTWARD ACROSS THE PLAINS ON FRIDAY, EXPANDING ACROSS IOWA AND MISSOURI FRIDAY NIGHT AND SATURDAY. CENTRAL ILLINOIS SHOULD REMAIN DRY THROUGH FRIDAY NIGHT, WITH A FEW SHOWERS POSSIBLY AFFECTING AREAS SW OF SPI TO EFFINGHAM ON SATURDAY. INCREASING CLOUDS ON SATURDAY WILL WORK TO KEEP HIGHS A FEW DEGREES BELOW POTENTIAL HIGHS, BUT WE STILL EXPECT MID 70S TO PREVAIL FOR HIGHS. THE LOW WILL BECOME AN OPEN WAVE SATURDAY NIGHT, AS UPPER JET SUPPORT DEVELOPS IN THE LEE OF THE TROUGH. THAT WILL WORK TO INCREASE COVERAGE OF SHOWERS AND A FEW THUNDERSTORMS FROM SOUTHWEST TO NORTHEAST ACROSS CENTRAL ILLINOIS SATURDAY NIGHT. AN INFLUX OF GULF MOISTURE WILL INCREASE LOW LEVEL INSTABILITY THROUGH THE WEEKEND. A BETTER CHANCE OF STRONG TO SEVERE STORMS LOOKS TO BE ON SUNDAY WHEN A SURFACE LOW LIFTS NORTHEAST ACROSS ILLINOIS. THE PASSAGE OF THE UPPER TROUGH AXIS SUNDAY NIGHT WILL CAUSE THUNDERSTORM CHANCES TO LINGER AT LEAST THROUGH MIDNIGHT. SPC HAS WESTERN IL IN THE DAY 4 15 PERCENT SEVERE OUTLOOK, WHICH INCLUDES 12Z SUNDAY TO 12Z MONDAY. WE KEPT LIKELY POPS ACROSS OUR AREA FROM LATE SATURDAY NIGHT THROUGH SUNDAY NIGHT. RAINFALL AND PERSISTENT CLOUD COVER SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL LIMIT DIURNAL TEMP SWINGS. LOWS SAT NIGHT WILL BE IN THE MID TO UPPER 50S, WITH HIGHS NEAR 70 ON SUNDAY. A MORE SIGNIFICANT AIRMASS CHANGE IS EXPECTED TO BEGIN SUNDAY NIGHT BEHIND A DEPARTING SURFACE COLD FRONT. A LONG WAVE TROUGH ALOFT WILL SETTLE INTO THE HEARTLAND, ALLOWING COOLER CANADIAN AIR TO SETTLE INTO OUR AREA. LIGHT RAINFALL WILL LINGER ON MONDAY MORNING, MAINLY EAST OF I-55, BUT CLOUDS SHOULD EVENTUALLY BEGIN TO CLEAR ACROSS WESTERN IL MONDAY AFTERNOON. AN EXTENDED PERIOD OF TEMPS AT OR BELOW NORMAL WILL CONTINUE FROM MONDAY THROUGH AT LEAST WEDNESDAY, AS THE UPPER TROUGH STALLS OVER THE GREAT LAKES AND NW FLOW DOMINATES ALOFT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 654 PM CDT THU APR 16 2015 VFR CONDITIONS WITH LIGHT WINDS THIS EVENING AS A SURFACE HIGH PRESSURE CENTER REMAINS NEAR THE NORTHEAST CORNER OF THE STATE. SCATTERED CUMULUS CLOUD COVER AT 4-5 KFT WILL TEND TO DISSIPATE OVERNIGHT WITH THE LOSS OF SURFACE HEATING. MODERATE AMOUNTS OF LOW LEVEL MOISTURE WILL REMAIN GIVEN THE LIGHT FLOW OVER THE REGION...AND WILL LIKELY RESULT IN SOME FOG FORMATION OVERNIGHT. WITH HIGHER DEWPOINTS TOWARD SOUTHEAST IL...EXPECT FOG TO BE MORE PREVALENT OVER KDEC-KBMI-KCMI EASTWARD...AND EXPECT AREAS OF IFR OR WORSE VISIBILITY TO DEVELOP BY 08Z-11Z. WITH DAYTIME HEATING...FOG SHOULD DISSIPATE 13Z-15Z WITH SCATTERED CUMULUS DEVELOPMENT ABOVE MVFR THRESHOLD. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ONTON SHORT TERM...HJS LONG TERM...SHIMON AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
229 PM CDT WED APR 15 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 229 PM CDT WED APR 15 2015 DEEP UPPER CUT-OFF ACROSS GREAT BASIN IS FORCING A VERY MERIDONAL PATTERN ACROSS NORTH AMERICA. A WAVE ROTATING AROUND THE EAST SIDE OF THE LOW IS PRODUCING SHOWERS AND CLOUDINESS ACROSS THE LOWER MISSOURI VALLEY. WITH MUCH OF THE WAVES ENERGY WEAKENING AS IT ENCOUNTERS THE EASTERN U.S. RIDGE AND THE VERY DRY AIR IN PLACE OVER ILLINOIS PROGRESS INTO THE FORECAST AREA IS SLOW. A SERIES OF SOUTHERN STREAM JET MAX MOVING ACROSS SOUTHERN TEXAS AND INTO THE SOUTHEAST U.S. MAY BE ABLE TO PROVIDE ADDITIONAL FORCING AND MOISTURE TO INTERACT WITH THE NORTHERN STREAM WAVE TO PRODUCE ABUNDANT CLOUD COVER BUT ONLY LIGHT PRECIP TONIGHT. THE BEST CHANCES SHOULD BE ACROSS THE SOUTH AND EAST WHERE THE INTERACTION BETWEEN THESE TWO FEATURES WILL BE THE MOST PRONOUNCED. && .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 229 PM CDT WED APR 15 2015 LATEST MODELS SUGGEST SHORT-WAVE RIDGING DEVELOPING OVER ILLINOIS THURSDAY NIGHT AS THE CUT-OFF LOW OVER WESTERN NORTH AMERICA BEGINS TO LIFT AND BE ABSORBED BY A STRONG NORTHERN STREAM SYSTEM CURRENTLY IN THE NORTHEAST PACIFIC. THIS SHOULD KEEP PRECIP MAINLY TO WEST OF THE FORECAST AREA THROUGH SATURDAY MORNING. BOTH 12Z ECMWF AND GFS ARE STRONGER WITH THE SURFACE REFLECTION OF THE SYSTEM SATURDAY NIGHT AND SUNDAY THEN THEIR PREVIOUS RUNS AND THE LATEST CANADIAN. WILL INTRODUCE THUNDER INTO SUNDAY AS GFS FORECASTED CAPE REACHES INTO THE SEVERAL HUNDRED RANGE WITH SOME MID-LEVEL COOLING AND DRYING EVIDENT IN BUFR SOUNDINGS COMBINED WITH THE PASSAGE OF THE MAIN SURFACE COLD FRONT. BY SUNDAY NIGHT AND MONDAY THERE BEGINS TO BE SOME SPREAD ON HOW FAST THE PRECIP PULLS EAST OF THE AREA. GIVEN THE STRENGTH OF THE TROUGH AM FAVORING ECMWF AND ITS SLOWER EVOLUTION. THIS WILL KEEP PRECIP CHANCES IN PLACE FOR MONDAY. STRONG NVA AFTER MONDAY NIGHT SHOULD PROVIDE SOME CLEARING, BUT WITH MID-LEVEL TEMPS IN THE -20 TO -30C RANGE DAY TIME DIURNAL CLOUDINESS AND POSSIBLY SOME RW- BY WEDNESDAY WILL BE POSSIBLE DUE TO STEEP LAPSE RATES. WITH SHORT-WAVE RIDGING AND RESULTANT HEIGHT RISES EXPECT TEMPS TO CLIMB WELL ABOVE SEASONAL NORMALS NEXT FEW DAYS WITH AFTERNOON TEMPS MOSTLY IN THE 70S THROUGH SATURDAY. MORE SEASONAL TEMPERATURES ARE EXPECTED ON SUNDAY WITH TEMPERATURES 5-10 DEGREES BELOW NORMAL FOR THE FIRST PART OF THE WORK WEEK. WILL NEED TO KEEP AN EYE ON LOW TEMPERATURE FORECASTS AND THE POTENTIAL FOR FROST DURING THIS PERIOD AS CURRENT PROGS SUGGEST SOME 30S POSSIBLE MAINLY ALONG AND NORTH OF I-74 AND RELATIVELY LIGHT WINDS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1229 PM CDT WED APR 15 2015 MAIN ISSUE FOR THE TAFS THIS RUN IS THE TIMING OF THE ADVANCING MOISTURE ADVECTION AND SUBSEQUENT CLOUD COVER AND DROPPING CATEGORIES. STARTING TO SEE SOME CIRRUS WORK INTO THE SOUTH...BUT SO FAR...ILX REMAINS MOSTLY SUNNY. TIMING OF CIG DROP BTWN 06Z AND 12Z TO REFLECT A CAT CHANGE AT SOME POINT...THOUGH MODELS ARE BEGINNING TO DELAY. OPEN WAVE APPROACHING THE RIDGE LATER TONIGHT IN THE EAST AND BREAKING DOWN THE HIGH PRESSURE MAINLY OVER EASTERN ILLINOIS. THREAT FOR SHOWERS GREATER IN CMI AND DEC...THOUGH WILL STILL BE LIKELY SCATTERED AT LEAST EARLY AND KEEPING TO VCSH FOR NOW STILL. LOWER CIGS ALSO ANTICIPATED POTENTIALLY AT THE MVFR/IFR BREAK IN THE FAR EAST WITH THE MORE SIGNIFICANT LAYER RH. DROPPING DEWPOINTS THIS AFTERNOON WILL HELP TO ERODE THE MOISTURE ADVECTING INTO THE REGION AT LEAST INITIALLY...AND THE GFS IS SHIFTING TO FAR LESS SATURATED THAN THE MORE AGGRESSIVE NAM. HRRR SO FAR IS ACTUALLY COMING IN PRETTY WET AS WELL AND MAY NEED TO ADJUST IF IT DOES NOT RESPOND...BUT FOR NOW AM KEEPING FROM A DRASTIC VIS DROP. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BARKER LONG TERM...BARKER AVIATION...HJS
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1239 PM CDT WED APR 15 2015 .UPDATE... ISSUED AT 1104 AM CDT WED APR 15 2015 SOME SCATTERED SHOWERS AROUND THE REGION WITH EASTERLY FLOW. CONCERN FOR PRECIP REALLY LATER IN THE DAY MAINLY AFTER 00Z AT THIS POINT WITH DRY AIR IN THE BOUNDARY LAYER ACCORDING TO THE 12Z SOUNDING. HAVE MADE A FEW ADJUSTMENTS TO THE TEMPS...AND WILL BE SENDING OUT AN UPDATE MOMENTARILY. NEED TO MAKE FURTHER ADJUSTMENTS TO THE DEWPOINTS WITH THAT DRY AIR MIXING OUT THE RH AT THE SFC LATER THIS AFTERNOON. && .SHORT TERM...(TODAY) ISSUED AT 330 AM CDT WED APR 15 2015 A WEAKENING UPPER-LEVEL LOW IS LIFTING SLOWLY NORTHEAST FROM THE PLAINS INTO THE MIDWEST. MEANWHILE, HIGH PRESSURE CENTERED OVER EASTERN CANADA, IS HELPING TO KEEP DRY LOW LEVEL FLOW IN PLACE ACROSS THE FORECAST AREA. MAIN CONCERN TODAY IS IF ANY RAINFALL CAN BE EXPECTED WITH THE APPROACH OF THE DECAYING UPPER LOW. THE OVERALL TREND THE PAST FEW DAYS HAS BEEN DRIER AND SLOWER LOCALLY AS FAR AS PRECIPITATION AMOUNTS AND TIMING LOCALLY. GIVEN THE WEAK FORCING WITH THE APPROACHING FEATURE, AND THE DRY AIRMASS THAT IT WILL BE PUSHING INTO, PLAN TO GO MOSTLY DRY TODAY. WILL ALLOW A SLIGHT CHANCE FOR SHOWERS BY LATE IN THE DAY ACROSS FAR SOUTHERN SECTIONS OF THE FORECAST AREA WHICH IS WHERE THE WEAK FORCING ARRIVES A LITTLE SOONER, AND THE AIRMASS IS NOT QUITE AS DRY. OTHERWISE, LOOKING FOR ANOTHER DAY WITH A GOOD DEAL OF CLOUD COVER, AND HIGHS IN THE MID-UPPER 60S. .LONG TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 330 AM CDT WED APR 15 2015 HAVE INCREASING CHANCES OF SHOWERS FROM THE SOUTH AND SW DURING TONIGHT WITH ISOLATED THUNDERSTORMS OVER SOUTHEAST IL OVERNIGHT AS WEATHER SURFACE LOW EJECTS NE FROM SOUTHERN PLAINS INTO THE LOWER OHIO RIVER VALLEY BY THU MORNING. CONTINUE CHANCES OF SHOWERS OVER MAINLY EASTERN IL THU WITH ISOLATED THUNDERSTORMS EAST OF I-57 ESPECIALLY NEAR THE IN BORDER. LOWS TONIGHT IN THE UPPER 40S NORTHERN COUNTIES AND MID 50S IN SOUTHEAST IL SOUTH OF I-70. HIGHS THU IN THE LOWER 70S WITH SOME UPPER 60S OVER EAST CENTRAL IL WHERE CLOUDS LINGER LONGER IN THE AFTERNOON. DRY CONDITIONS EXPECTED THU NIGHT WITH JUST 20% CHANCE OF SHOWERS AND POSSIBLY A THUNDERSTORM ON FRIDAY THOUGH MOST AREAS WILL STAY DRY DURING THIS TIME AS SURFACE HIGH PRESSURE SETTLES NEAR IL AND GET SOME WEAK UPPER LEVEL RIDGING. FRIDAY STILL LOOKS LIKE THE MILDEST DAY WITH HIGHS IN THE MID 70S. MODELS STILL DIFFER WITH HANDLING EJECTING OF CUTOFF UPPER LEVEL LOW FROM THE SOUTHERN ROCKIES INTO IL AS AN UPPER TROF BY SUNDAY, AND ASSOCIATED QPF FIELDS. GFS STILL BRINGS IN QPF INTO CENTRAL IL DURING THE DAY SAT WHILE ECMWF MODELS KEEPS QPF JUST SW OF CENTRAL IL DURING DAY ON SATURDAY, THEN SPREADS IT NE ACROSS CENTRAL IL DURING SAT NIGHT AND SUNDAY. TRIMMED POPS ON SAT TO DRY IN NNE COUNTIES FROM I-74 NE AND SLIGHT CHANCES CENTRAL/SW COUNTIES SW OF I- 74 , THEN BRING POPS UPWARD FROM SW TO NE DURING SAT NIGHT INTO SUNDAY. HIGHS SAT AROUND 70F AND MID TO UPPER 60S ON SUNDAY DUE TO MORE CLOUDS AND SHOWERS AROUND. CONTINUED GOOD CHANCES OF SHOWERS FROM SUNDAY THROUGH MONDAY WITH ISOLATED THUNDERSTORMS OVER SOUTHEAST IL. COOLER HIGHS OF 59-65F ON MONDAY AS UPPER LEVEL TROF ARRIVES EARLY NEXT WEEK. HAVE DRY CONDITIONS RETURNING MONDAY NIGHT AND TUE AS UPPER LEVEL TROF/LOW PULLS UP INTO THE GREAT LAKES REGION WHERE BETTER CHANCES OF SHOWERS WILL BE THEN. HIGHS TUE MOSTLY IN THE LOWER 60S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1229 PM CDT WED APR 15 2015 MAIN ISSUE FOR THE TAFS THIS RUN IS THE TIMING OF THE ADVANCING MOISTURE ADVECTION AND SUBSEQUENT CLOUD COVER AND DROPPING CATEGORIES. STARTING TO SEE SOME CIRRUS WORK INTO THE SOUTH...BUT SO FAR...ILX REMAINS MOSTLY SUNNY. TIMING OF CIG DROP BTWN 06Z AND 12Z TO REFLECT A CAT CHANGE AT SOME POINT...THOUGH MODELS ARE BEGINNING TO DELAY. OPEN WAVE APPROACHING THE RIDGE LATER TONIGHT IN THE EAST AND BREAKING DOWN THE HIGH PRESSURE MAINLY OVER EASTERN ILLINOIS. THREAT FOR SHOWERS GREATER IN CMI AND DEC...THOUGH WILL STILL BE LIKELY SCATTERED AT LEAST EARLY AND KEEPING TO VCSH FOR NOW STILL. LOWER CIGS ALSO ANTICIPATED POTENTIALLY AT THE MVFR/IFR BREAK IN THE FAR EAST WITH THE MORE SIGNIFICANT LAYER RH. DROPPING DEWPOINTS THIS AFTERNOON WILL HELP TO ERODE THE MOISTURE ADVECTING INTO THE REGION AT LEAST INITIALLY...AND THE GFS IS SHIFTING TO FAR LESS SATURATED THAN THE MORE AGGRESSIVE NAM. HRRR SO FAR IS ACTUALLY COMING IN PRETTY WET AS WELL AND MAY NEED TO ADJUST IF IT DOES NOT RESPOND...BUT FOR NOW AM KEEPING FROM A DRASTIC VIS DROP. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HJS SHORT TERM...BAK LONG TERM...07 AVIATION...HJS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
612 PM CDT THU APR 16 2015 ...UPDATED AVIATION DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 120 PM CDT THU APR 16 2015 IN THE SHORT TERM, A FEW (2-3) ROUNDS OF CONVECTION ARE ANTICIPATED THROUGH HE NEXT 24 TO 36 HOURS OR SO AS A LARGE UPPER LOW MOVES TOWARD THE REGION WITH FORCING FOR ASCENT, AND PERSISTENT MID LEVEL MOISTURE ADVECTION TO MAINTAIN INSTABILITY FOR A PROLONGED PERIOD. THE FIRST ROUNDS ARE EXPECTED ALREADY EARLY THIS AFTERNOON AS THE NESTED 4 KM NAM AND HRRR MODELS HAVE GENERALLY AGREED ON CONVECTIVE INITIATION BETWEEN AROUND 2 AND 4 PM, AND RAPIDLY DEVELOPING INTO A MULTICELLULAR LINE AFTER AN HOUR OR SO OF SLOWER GROWING DISCREET CELLS. THE INITIAL ROTATING STORMS GENERALLY WEST OF HIGHWAY 83 SHOULD BE CAPABLE OF PRODUCING HAIL LARGER THAN GOLFBALLS AND DAMAGING WIND BEFORE THE STORMS BECOME MORE CLUSTERED OR LINEAR, PRESENTING A SLIGHTLY SMALLER HAIL THREAT AND STILL DAMAGING WIND THREAT THROUGH THE HIGHWAY 283 AND 183 CORRIDORS INTO THE EARLY EVENING HOURS. THESE MODEL SOLUTIONS COULD BE INTERFERED WITH BY THE EXTENSIVE STRATUS ACROSS THE AREA REDUCING THE SEVERE THREAT. ANOTHER ROUND OF THUNDERSTORMS WILL PROBABLY OCCUR LATE TONIGHT INTO THE OVERNIGHT AND POSSIBLY STILL ONGOING EARLY FRIDAY MORNING, WITH A CONTINUED HAIL IF NOT AN ISOLATED WIND THREAT AS WELL, ALTHOUGH SOME BL STABILITY SHOULD HINDER THE WIND THREAT. THE DYNAMICS OF THE UPPER LOW WILL DRIVE A DRY SLOT THROUGH THE REGION OF FRIDAY, BUT NOT BEFORE LATE MORNING/EARLY AFTERNOON DESTABILIZATION CONTRIBUTES TO YET ANOTHER SEVERE EPISODE WITH AS GOOD OR BETTER CAPE AND SHEAR COMBINATIONS. TEMPERATURES WERE RAISED FOR FRIDAY MORNING, FOLLOWING THE NAM AND GFS, AS OVERNIGHT CONVECTION SHOULD LIMIT THE RADIATIONAL COOLING. ADDITIONALLY THE POPS WERE RAISED LOWERED FRIDAY MORNING AND INCREASED ALONG THE MOISTURE TRANSPORT AXIS INTO FRIDAY AFTERNOON WITH A MODEL CONSENSUS. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 1152 AM CDT THU APR 16 2015 FRIDAY NIGHT INTO SATURDAY WE WILL STILL BE DEALING WITH THE SLOW- MOVING UPPER LOW, BUT BY THIS TIME THE LOW WILL BE SEVERELY OCCLUDED WITH THE DRY INTRUSION WORKING IN FAST FROM THE SOUTHWEST. IN FACT, FRIDAY NIGHT LOOKS RATHER DRY NOW WITH THE SYNOPTIC DRY INTRUSION ACROSS MUCH OF KANSAS. WE HAVE REDUCED POPS AS A RESULT FRIDAY NIGHT. AS WE HEAD INTO SATURDAY, ANY DAYTIME HEATING WILL PROMOTE SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT AS THE CORE OF THE MID LEVEL CYCLONE WALLOWS SLOWLY EASTWARD INTO FAR WESTERN KANSAS. WE WILL MAINTAIN THE 20-40 POPS ACROSS MAINLY THE NORTHERN AND EASTERN ZONES WITH A DRY FORECAST ACROSS FAR SOUTHWEST KANSAS. WHAT IS LEFT OF THE LOW WILL FINALLY PULL AWAY SATURDAY NIGHT INTO EARLY SUNDAY WITH FAIRLY STRONG NORTH WINDS TO FOLLOW DURING THE DAY SUNDAY. WE COULD STILL SEE SOME WRAP-AROUND LIGHT PRECIPITATION IN THE WEAKENING MID LEVEL DEFORMATION AXIS, HENCE THE 20 TOP 30 POPS FOR MUCH OF THE AREA. LOOKING BEYOND THE WEEKEND, WE WILL ENTER A NORTHWEST FLOW PATTERN ON THE SOUTHWEST SIDE OF A LARGE-SCALE UPPER TROUGH ACROSS THE GREAT LAKES REGION. THE ATMOSPHERE WILL BE FAIRLY COOL EARLY NEXT WEEK AS A RESULT WITH LARGE SCALE HIGH PRESSURE AT THE SURFACE. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 611 PM CDT THU APR 16 2015 CONVECTION CAN BE EXPECTED THROUGH AT LEAST MIDNIGHT AS UPPER LEVEL DISTURBANCE APPROACHES WESTERN KANSAS. PRECIPITATION CHANCES WILL THEN DECREASE FROM SOUTHWEST TO NORTHEAST EARLY FRIDAY MORNING AS THIS UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS. CEILINGS OVERNIGHT WILL VARY FROM VFR TO IFR AS AREAS OF CONVECTION CROSSES EACH OF THE TAF SITES. WILL INITIALLY BE OPTIMISTIC WITH THE CEILINGS EARLY IN THE EVENING WITH CEILINGS LOWERING AS PRECIPITATION CHANCES INCREASE TOWARDS MIDNIGHT. AS THE PRECIPITATION TAPERS OFF TOWARDS DAYBREAK THERE WILL THEN BE A CHANCE FOR AREAS OF STATUS AND FOG DEVELOPING GIVEN THE LOW LEVEL MOISTURE AND A SOUTHEASTERLY WIND. CEILINGS WILL THEN IMPROVE BY LATE MORNINGS AS SOUTH/SOUTHEASTERLY WINDS CONTINUE. && .PRELIMINARY POINT TEMPS/POPS... DDC 55 71 47 69 / 80 60 60 30 GCK 53 71 43 69 / 80 50 60 30 EHA 47 71 42 66 / 70 30 30 20 LBL 50 73 43 69 / 80 40 40 30 HYS 56 71 50 71 / 70 60 60 50 P28 58 72 55 72 / 80 60 60 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RUSSELL LONG TERM...UMSCHEID AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS JACKSON KY
1007 PM EDT THU APR 16 2015 .UPDATE... ISSUED AT 1004 PM EDT THU APR 16 2015 PRECIP HAS DIED OUT OVER THE JKL FORECAST AREA FOR THE TIME BEING. THERE WERE SHOWERS OCCURRING FROM WESTERN KY TO SOUTHWESTERN OH. SHORT RANGE MODELS SUGGEST THIS AREA OF SHOWERS WILL SAG SOUTHEAST AND ADDITIONAL SHOWER DEVELOPMENT WILL ALSO OCCUR OVER EASTERN KY A LITTLE BEFORE DAWN. HAVE USED 20-30 PERCENT POP TO ACCOUNT FOR THIS. MODELS ALSO SHOW A SMALL RESURGENCE OF SHOWERS LATE FRIDAY AFTER SOME DESTABILIZATION OCCURS. IF IT OCCURS...THINK THE ACTIVITY WOULD BE VERY ISOLATED. FORECAST SOUNDINGS SHOW VERY DRY AIR ALOFT THAT THE CONVECTIVE CURRENTS WOULD BE RISING INTO. WITHOUT A STRONG FOCUS/FORCING MECHANISM...DRY AIR ENTRAINMENT COULD BE THE DEMISE OF WHAT WOULD OTHERWISE BE MORE PLENTIFUL ACTIVITY. UPDATE ISSUED AT 615 PM EDT THU APR 16 2015 UPDATED POPS FROM FRIDAY INTO SATURDAY. LATEST MODEL RUNS SUGGEST THE TIME FRAME FROM LATE FRIDAY THROUGH SATURDAY WILL LIKELY BE DRY. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 306 PM EDT THU APR 16 2015 WITH THE LATEST RUN OF THE HRRR MODEL BEING A BIT OFF WITH ITS HANDLING OF TODAYS CONVECTION...THE NAM12 WAS MODEL OF CHOICE FOR THE SHORT TERM PORTION OF THE FORECAST. SHOWERS AND STORMS THAT HAVE BEEN MOVING ACROSS EASTERN KENTUCKY THROUGHOUT THE DAY ARE CURRENTLY AFFECTING THE NORTHEASTERN PORTION OF THE THE AREA. THIS ACTIVITY IS EXPECTED TO MOVE ON OUT OF THE AREA IN THE NEXT FEW HOURS. CURRENT RADAR INDICATES THAT ISOLATED TO SCATTERED SHOWERS AND STORMS WILL CONTINUE TO MOVE INTO THE AREA FROM THE SOUTHWEST DURING THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. ONLY ISOLATED ACTIVITY...IF THAT...WILL BE LEFT OVER FOR THE OVERNIGHT HOURS. SHOWERS AND STORMS WILL BE POSSIBLE DURING THE DAY ON FRIDAY...AS A WEAK FRONTAL BOUNDARY MOVES IN FROM THE WEST. WEAK DISTURBANCES AHEAD OF THIS FRONT MAY ALSO KICK OFF SHOWERS AND STORMS...BUT WITH A LACK OF INSTABILITY AND STRONG LIFT...IT APPEARS THAT THE COVERAGE OF PRECIPITATION WILL BE SPARSE. BASED ON THE LATEST MODEL DATA...THERE SHOULD BE LULL IN THE ACTION FROM LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING...AS A WEAK RIDGE OF HIGH PRESSURE BRIEFLY SETTLES OVER THE AREA. TEMPERATURES DURING THE PERIOD WILL BE WELL ABOVE NORMAL FOR THIS TIME OF YEAR...WITH HIGHS ON FRIDAY MAXING OUT IN THE 70S...AND OVERNIGHT LOWS TONIGHT AND FRIDAY NIGHT BOTTOMING OUT IN THE LOW TO MID 50S AREA WIDE. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 340 PM EDT THU APR 16 2015 MAIN CONCERN DURING THE EXTENDED PERIOD IS FOCUSED ON A CUT OFF LOW CURRENTLY OVER THE FOUR CORNERS REGION. THIS LOW IS PROGGED TO PUSH SLOWLY EWD EARLY SATURDAY BEFORE ITS ENERGY GETS INGESTED AND HELPS DEEPEN A NORTHERN STREAM TROUGH. THIS TROUGH WILL MOVE ALONG THE US/CANADIAN BORDER UNTIL THE CLOSED LOW ENERGY PHASES WITH IT AND MOVES EAST. IN ADDITION TO THE UPPER LEVEL TROUGH...A SFC LOW IS FORECASTED TO DEVELOP SATURDAY NIGHT OVER THE PLAINS AND AHEAD OF IT...A STRONG SURGE OF GULF MOISTURE RETURNS TO THE OH AND TN VALLEYS. PW VALUES UP TO 1.4 INCHES ARE EXPECTED WITH THIS NEW SURGE OF MOISTURE....WHICH ARE WELL ABOVE AVERAGE. THERE WILL BE SOME MODERATE INSTABILITY AS WELL. THIS SYSTEM SHOULD PUSH OUT OF KY BY MONDAY NIGHT. ON TUESDAY...A LOW THAT IS NOW CUT OFF IN THE NORTHERN STREAM WILL UNDULATE OVER THE GREAT LAKES REGION THROUGH THURSDAY WITH PIECES OF ENERGY WRAPPING AROUND IT. HOWEVER...THIS SHOULDN/T CAUSE ANY ISSUES FOR KENTUCKY AS THE ENERGY APPEARS TO STAY FURTHER NORTH UNTIL THURSDAY WHEN THE LOW STARTS SAGGING SOUTHEASTWARD. AT THE SFC...SATURDAY WILL BE MAINLY DRY AND WARM UNTIL LATE AFTERNOON WHEN CHANCES FOR PRECIP BEGIN INCREASING. THE BULK OF THE RAINFALL WILL FALL SUNDAY INTO MONDAY WHERE AT LEAST AN INCH OF LIQUID IS LIKELY ACROSS EASTERN KENTUCKY. THERE IS ALSO A CHANCE FOR THUNDERSTORMS DURING THIS TIME GIVEN THE MOIST AIR MASS IN PLACE AND PLENTY OF SFC/UPPER LEVEL DYNAMICS. AS THIS SYSTEM EXITS THE AREA MONDAY NIGHT...THINGS WILL DRY OUT AND EASTERN KENTUCKY WILL GET A REPRIEVE FROM PRECIPITATION TUESDAY AND WEDNESDAY. TEMPERATURES DURING THIS TIME WILL BE A BIT BELOW NORMAL IF NOT RIGHT AT SEASONABLE LEVELS. RAIN CHANCES RETURN ON THURSDAY AS THE LOW SAGS SOUTHEASTWARD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 836 PM EDT THU APR 16 2015 MOST OF THE SHOWERS WHICH AFFECTED THE REGION DURING THE DAY HAD DIMINISHED OR MOVED OUT OF THE AREA AT THE START OF THE PERIOD...AND CONDITIONS WERE MAINLY VFR. THIS SHOULD LAST WELL INTO THE NIGHT. HOWEVER...A GENERAL DETERIORATION IN CONDITIONS IS EXPECTED OVERNIGHT. MOST PLACES WILL FALL TO MVFR...AND PERHAPS SOME IFR FOR A TIME. CONFIDENCE IN THE RATE OF DETERIORATION IS NOT HIGH...BUT THE BEST ESTIMATE IS FOR A DECLINE AROUND 09Z. SCATTERED SHOWERS ARE ALSO EXPECTED...BUT THE PROBABILITY AT ANY GIVEN TIME/PLACE IS TOO LOW TO WARRANT MORE THAN VCSH IN TAFS. IMPROVEMENT IS EXPECTED ON FRIDAY AFTERNOON...WITH MAINLY VFR RETURNING AROUND 19Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HAL SHORT TERM...AR LONG TERM...JVM AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
836 PM EDT THU APR 16 2015 .UPDATE... ISSUED AT 615 PM EDT THU APR 16 2015 UPDATED POPS FROM FRIDAY INTO SATURDAY. LATEST MODEL RUNS SUGGEST THE TIME FRAME FROM LATE FRIDAY THROUGH SATURDAY WILL LIKELY BE DRY. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 306 PM EDT THU APR 16 2015 WITH THE LATEST RUN OF THE HRRR MODEL BEING A BIT OFF WITH ITS HANDLING OF TODAYS CONVECTION...THE NAM12 WAS MODEL OF CHOICE FOR THE SHORT TERM PORTION OF THE FORECAST. SHOWERS AND STORMS THAT HAVE BEEN MOVING ACROSS EASTERN KENTUCKY THROUGHOUT THE DAY ARE CURRENTLY AFFECTING THE NORTHEASTERN PORTION OF THE THE AREA. THIS ACTIVITY IS EXPECTED TO MOVE ON OUT OF THE AREA IN THE NEXT FEW HOURS. CURRENT RADAR INDICATES THAT ISOLATED TO SCATTERED SHOWERS AND STORMS WILL CONTINUE TO MOVE INTO THE AREA FROM THE SOUTHWEST DURING THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. ONLY ISOLATED ACTIVITY...IF THAT...WILL BE LEFT OVER FOR THE OVERNIGHT HOURS. SHOWERS AND STORMS WILL BE POSSIBLE DURING THE DAY ON FRIDAY...AS A WEAK FRONTAL BOUNDARY MOVES IN FROM THE WEST. WEAK DISTURBANCES AHEAD OF THIS FRONT MAY ALSO KICK OFF SHOWERS AND STORMS...BUT WITH A LACK OF INSTABILITY AND STRONG LIFT...IT APPEARS THAT THE COVERAGE OF PRECIPITATION WILL BE SPARSE. BASED ON THE LATEST MODEL DATA...THERE SHOULD BE LULL IN THE ACTION FROM LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING...AS A WEAK RIDGE OF HIGH PRESSURE BRIEFLY SETTLES OVER THE AREA. TEMPERATURES DURING THE PERIOD WILL BE WELL ABOVE NORMAL FOR THIS TIME OF YEAR...WITH HIGHS ON FRIDAY MAXING OUT IN THE 70S...AND OVERNIGHT LOWS TONIGHT AND FRIDAY NIGHT BOTTOMING OUT IN THE LOW TO MID 50S AREA WIDE. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 340 PM EDT THU APR 16 2015 MAIN CONCERN DURING THE EXTENDED PERIOD IS FOCUSED ON A CUT OFF LOW CURRENTLY OVER THE FOUR CORNERS REGION. THIS LOW IS PROGGED TO PUSH SLOWLY EWD EARLY SATURDAY BEFORE ITS ENERGY GETS INGESTED AND HELPS DEEPEN A NORTHERN STREAM TROUGH. THIS TROUGH WILL MOVE ALONG THE US/CANADIAN BORDER UNTIL THE CLOSED LOW ENERGY PHASES WITH IT AND MOVES EAST. IN ADDITION TO THE UPPER LEVEL TROUGH...A SFC LOW IS FORECASTED TO DEVELOP SATURDAY NIGHT OVER THE PLAINS AND AHEAD OF IT...A STRONG SURGE OF GULF MOISTURE RETURNS TO THE OH AND TN VALLEYS. PW VALUES UP TO 1.4 INCHES ARE EXPECTED WITH THIS NEW SURGE OF MOISTURE....WHICH ARE WELL ABOVE AVERAGE. THERE WILL BE SOME MODERATE INSTABILITY AS WELL. THIS SYSTEM SHOULD PUSH OUT OF KY BY MONDAY NIGHT. ON TUESDAY...A LOW THAT IS NOW CUT OFF IN THE NORTHERN STREAM WILL UNDULATE OVER THE GREAT LAKES REGION THROUGH THURSDAY WITH PIECES OF ENERGY WRAPPING AROUND IT. HOWEVER...THIS SHOULDN/T CAUSE ANY ISSUES FOR KENTUCKY AS THE ENERGY APPEARS TO STAY FURTHER NORTH UNTIL THURSDAY WHEN THE LOW STARTS SAGGING SOUTHEASTWARD. AT THE SFC...SATURDAY WILL BE MAINLY DRY AND WARM UNTIL LATE AFTERNOON WHEN CHANCES FOR PRECIP BEGIN INCREASING. THE BULK OF THE RAINFALL WILL FALL SUNDAY INTO MONDAY WHERE AT LEAST AN INCH OF LIQUID IS LIKELY ACROSS EASTERN KENTUCKY. THERE IS ALSO A CHANCE FOR THUNDERSTORMS DURING THIS TIME GIVEN THE MOIST AIR MASS IN PLACE AND PLENTY OF SFC/UPPER LEVEL DYNAMICS. AS THIS SYSTEM EXITS THE AREA MONDAY NIGHT...THINGS WILL DRY OUT AND EASTERN KENTUCKY WILL GET A REPRIEVE FROM PRECIPITATION TUESDAY AND WEDNESDAY. TEMPERATURES DURING THIS TIME WILL BE A BIT BELOW NORMAL IF NOT RIGHT AT SEASONABLE LEVELS. RAIN CHANCES RETURN ON THURSDAY AS THE LOW SAGS SOUTHEASTWARD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 836 PM EDT THU APR 16 2015 MOST OF THE SHOWERS WHICH AFFECTED THE REGION DURING THE DAY HAD DIMINISHED OR MOVED OUT OF THE AREA AT THE START OF THE PERIOD...AND CONDITIONS WERE MAINLY VFR. THIS SHOULD LAST WELL INTO THE NIGHT. HOWEVER...A GENERAL DETERIORATION IN CONDITIONS IS EXPECTED OVERNIGHT. MOST PLACES WILL FALL TO MVFR...AND PERHAPS SOME IFR FOR A TIME. CONFIDENCE IN THE RATE OF DETERIORATION IS NOT HIGH...BUT THE BEST ESTIMATE IS FOR A DECLINE AROUND 09Z. SCATTERED SHOWERS ARE ALSO EXPECTED...BUT THE PROBABILITY AT ANY GIVEN TIME/PLACE IS TOO LOW TO WARRANT MORE THAN VCSH IN TAFS. IMPROVEMENT IS EXPECTED ON FRIDAY AFTERNOON...WITH MAINLY VFR RETURNING AROUND 19Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HAL SHORT TERM...AR LONG TERM...JVM AVIATION...HAL
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
345 PM EDT WED APR 15 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 340 PM EDT WED APR 15 2015 18Z SFC ANALYSIS SHOWS THAT THE INVERTED TROUGH AXIS HAS SHIFTED EAST TO ALONG THE SPINE OF THE APPALACHIANS WITH THE LOWER MISSISSIPPI VALLEY LOW/S WARM FRONT LIFTING NORTH INTO KENTUCKY. THE LIGHT PCPN AND OVERCAST CONDITIONS HAS KEPT MOST OF THE AREA ON THE COOL SIDE TODAY...ESPECIALLY OUTSIDE OF THE CUMBERLAND VALLEY. HOWEVER...THINNING CLOUDS AND A BREAK IN THE LIGHT RAIN SHOULD ALLOW FOR SOME DECENT TEMP RISES OVER THE NEXT COUPLE OF HOURS FOR ALL BUT THE FAR NORTHEAST. READINGS CURRENTLY VARY FROM THE UPPER 50S IN THE NORTHEAST TO THE UPPER 60S IN THE SOUTH WHILE DEWPOINTS RANGE FROM NEAR 60 SOUTH TO THE UPPER 40S IN THE FAR NORTH. WINDS ARE GENERALLY FROM THE EAST TO NORTHEAST AT 10 TO 15 MPH OVER THE NORTHERN HALF OF THE AREA WHILE THEY ARE A BIT LIGHTER AND MORE VARIABLE TO THE SOUTH. THE LIFTING WARM FRONT MAY REINITIATE SHOWERS LATER IN THE AFTERNOON INTO THE EVENING... PER THE LATEST HRRR AND NAM12...BUT RIGHT NOW THE RADAR SCOPE IS PRETTY CLEAN. SHOULD CONVECTION REDEVELOP...SOME THUNDER MAY EVEN BE POSSIBLE GIVEN THE RISING TEMPS/INSTABILITY...ESPECIALLY IN THE SOUTH. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS A FEW CLUSTERS OF MID LEVEL ENERGY WILL BRUSH KENTUCKY AS THEY MOVE INTO THE OHIO VALLEY TONIGHT ON THE NORTHWEST FRINGE OF A BUILDING RIDGE. THE RIDGE FLATTENS A BIT ON THURSDAY AS ADDITIONAL ENERGY PASSES THROUGH NORTHERN KENTUCKY THAT AFTERNOON/OVERNIGHT AND INTO FRIDAY MORNING. TO THE WEST...A SLOW MOVING CLOSED LOW SPINS ESSENTIALLY IN PLACE NEAR THE FOUR CORNERS REGION OF THE COUNTRY...SERVING AS A SOURCE REGION FOR ENERGY ABLE TO ESCAPE AND DRIFT EAST IN THE SOUTHERN STREAM THAT CONTINUES TO DOMINATE KENTUCKY/S WX. GIVEN THE GENERAL MODEL AGREEMENT HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE HRRR AND NAM12 FOR WEATHER SPECIFICS DUE TO THEIR HIGHER RESOLUTION... THOUGH CURRENT CONDITIONS AND TRENDS ARE ALSO OF HIGH RELEVANCE INTO THE NEAR TERM PORTION OF THE FORECAST. SENSIBLE WEATHER WILL FEATURE A POTENTIAL FOR SHOWERS INTO THE EVENING AS THE SFC FRONT LIFTS NORTHEAST THROUGH THE AREA WITH A THUNDERSTORM POSSIBLE...AS WELL. ADDITIONAL CONVECTION WILL BE POSSIBLE INTO THURSDAY MORNING WITH THE SFC LOW TO THE SOUTHWEST APPROACHING. THIS WILL LIKELY LIFT ANOTHER BOUNDARY THROUGH EASTERN KENTUCKY DURING THE DAY WITH SHOWERS AND STRAY STORMS A GOOD BET. THE PCPN CHANCES WILL DIMINISH INTO FRIDAY MORNING BUT CANNOT GO DRY ATTM GIVEN THE ENVIRONMENT. THIS REMAINS A LOW CONFIDENCE FORECAST WITH RESPECT TO SPECIFIC DETAILS BUT IN GENERAL YOU CAB BANK ON RELATIVELY WARM AND MOIST CONDITIONS CONTINUING. USED THE SHORTBLEND GUIDANCE AS A STARTING POINT FOR T/TD/WIND GRIDS THROUGH THE FIRST 18-24 HOURS OF THE FORECAST FOLLOWED BY THE SUPERBLEND. GIVEN THE HUMID CONDITIONS MADE ONLY MINOR TERRAIN BASED ADJUSTMENTS TO TEMPERATURES TONIGHT AND THURSDAY NIGHT. AS FOR POPS...ENDED UP ON THE LOW SIDE OF MOS GUIDANCE TONIGHT AND THURSDAY...BUT IN LINE FOR THURSDAY NIGHT. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 340 PM EDT WED APR 15 2015 THE EXTENDED PERIOD WILL BE DOMINATED BY A LARGE CLOSED LOW OVER THE FOUR CORNERS REGION WITH SOME SLIGHT RIDGING OVER THE EASTERN CONUS. AFTER A SHORT WAVE IMPULSE...PROVIDING A ROUND OF RAINFALL TO THE REGION...PUSHES THROUGH THE TN AND OH VALLEYS FRIDAY MORNING... FRIDAY EVENING INTO SATURDAY MORNING WILL BE MOSTLY DRY. ON SATURDAY...ANOTHER IMPULSE MOVING ALONG THE NORTHERN STREAM PUSHES EWD TOWARDS THE GREAT LAKES REGION. AT THE SAME TIME...THE CLOSED LOW EJECTS EWD AS WELL. THE ENERGY FROM THE CLOSED LOW THEN FEEDS INTO THE NORTHERN STREAM TROUGH AND HELPS DEEPEN/INTENSIFY IT. THIS SYSTEM WILL PROVIDE THE BEST CHANCE FOR A SIGNIFICANT AMOUNT OF RAINFALL FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY MORNING TIME FRAME. THIS RAINFALL HAS THE POSSIBILITY OF BREAKING THE JKL/S ALL-TIME APRIL RAINFALL RECORD...CURRENTLY WE HAVE HAD THE SECOND WETTEST APRIL ON RECORD. IN FACT...THIS SYSTEM WILL SPREAD PRECIP FROM THE NORTHERN MISSISSIPPI VALLEY REGION ACROSS MOST OF THE EASTERN CONUS THROUGH TUESDAY. CLOSER TO HOME...TUESDAY AND WEDNESDAY LOOKS TO BE FAIRLY QUIET...COOLER...AND DRY AS THE UPPER LEVELS TRANSITION TO MORE OF A ZONAL FLOW PATTERN. GFS AND ECMWF MODELS ACTUALLY HAVE GOOD AGREEMENT WITH THE EVOLUTION OF THIS MAJOR SYSTEM. ADDITIONALLY...THERE LOOKS TO BE A STRONG SURGE OF GULF MOISTURE WITH PW VALUES REACHING 1.50 INCHES IN SOME LOCATIONS WITH SOME INSTABILITY PRESENT. THEREFORE...HAVE DECIDED TO INCLUDED SLIGHT CHANCES OF THUNDER THROUGHOUT THE EXTENDED PERIOD WITH LIKELY THUNDER DURING THE SUNDAY AFTERNOON THROUGH MONDAY MORNING TIME FRAME. PROBABLY COULD HAVE UPPED POPS TO GO CATEGORICAL ON SUNDAY/MONDAY MORNING BUT HAVE REMAINED CONSISTENT WITH NEIGHBORS FOR NOW AND KEPT LIKELY POPS IN THE GRIDS. ALL IN ALL...BASED ON THE CONTINUED WET PATTERN...THE MAIN CONCERN DURING THE EXTENDED PERIOD WILL BE HEAVY RAINFALL WITH LOCALIZED FLOODING CONCERNS...ESPECIALLY IN AREAS THAT RECEIVE SEVERAL ROUNDS OF RAINFALL AND WHERE RIVERS AND CREEKS ARE STILL RUNNING HIGH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 225 PM EDT WED APR 15 2015 SCATTERED LIGHT SHOWERS CONTINUE TO DRIFT THROUGH EAST KENTUCKY THIS AFTERNOON...BUT COVERAGE IS CERTAINLY ON THE WANE. WITH THIS...VISIBILITIES HAVE STAYED UP...EVEN IN THE RAIN...WHILE CIGS HAVE BEEN MOSTLY LIFR...BUT RATHER VARIABLE. THE LOW LEVEL FLOW WILL SHIFT TO A MORE SOUTHEASTERLY DIRECTION TONIGHT AND THIS DRIER...DOWNSLOPING FLOW WILL HELP TO SCOUR OUT THE LOWER CIGS. AS SUCH...EXPECT A RETURN TO MVFR OR VFR CONDITIONS AT MOST LOCATIONS DURING THE EARLY EVENING WITH VFR EXPECTED THROUGH THE MORNING...THURSDAY. AS SHOWERS WILL BE AROUND HAVE KEPT VCSH IN ALL THE TAFS THROUGH THE PERIOD...WHILE WINDS ARE EXPECTED TO BE LIGHT AND VARIABLE. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...JVM AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
250 PM EDT WED APR 15 2015 .UPDATE... ISSUED AT 250 PM EDT WED APR 15 2015 DID A QUICK UPDATE TO THE POP AND WX GRIDS PER THE LATEST RADAR TRENDS AND HRRR GUIDANCE. ALSO FINE TUNED TEMPS AND DEWPOINTS THROUGH THE REST OF THE DAY BASED ON THE LATEST SHORTBLEND GUIDANCE AND THE OBS/TRENDS. THESE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1105 AM EDT WED APR 15 2015 14Z SFC ANALYSIS SHOWS AN INVERTED TROUGH LYING THROUGH EASTERN KENTUCKY FROM AN AREA OF LOW PRESSURE OVER THE LOWER MISSISSIPPI VALLEY. ON RADAR...SHOWERS...MAINLY LIGHT...CONTINUE TO SPREAD NORTHEAST THROUGH EASTERN KENTUCKY. CLOUDS COVER THE AREA WITH TEMPERATURES OFF TO A SLOW START. CURRENTLY...WITH EAST TO NORTHEAST WINDS OF 5 TO 10 MPH...TEMPERATURES ARE IN THE LOW TO MID 50S NORTH AND NEAR 60 DEGREES IN THE FAR SOUTH. DEWPOINTS VARY FROM THE LOW 40S IN THE FAR NORTH TO MID AND UPPER 50S IN THE FAR SOUTH. THE LATEST HRRR AND NAM12 GUIDANCE SUGGESTS THAT THE RAIN LINGERS MORE OVER THE WESTERN AND CENTRAL PARTS OF THE CWA THROUGH MID AFTERNOON THAN WE HAD INITIALLY REPRESENTED IN THE GRIDS. ACCORDINGLY...HAVE TWEAKED THE POP AND WEATHER GRIDS TO REFLECT THIS CHANGE...ALSO KEEPING THE SMALL POTENTIAL FOR A THUNDERSTORM THIS AFTERNOON. FINALLY...SLOWED THE RISE OF TEMPERATURES THROUGH EARLY AFTERNOON DUE TO THE CLOUDS AND PCPN. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. AN UPDATED SET OF ZONE WILL BE ISSUED SHORTLY...AS WELL. UPDATE ISSUED AT 640 AM EDT WED APR 15 2015 RAIN CONTINUES TO PROGRESS UP THE CUMBERLAND VALLEY AND HAVE INCREASED POPS FURTHER OVER SOUTHEAST KENTUCKY. STILL A LITTLE UNSURE HOW FAR TO THE NORTH AND WEST THE RAIN WILL GET CONSIDERING DRIER AIR IN PLACE BUT THE LATEST HRRR BRINGS THE RAIN AS FAR WEST AS JACKSON AND THAT SEEMS REASONABLE. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 337 AM EDT WED APR 15 2015 MOIST SOUTHWEST FLOW ALOFT WILL REMAIN IN PLACE THROUGH THE SHORT TERM PERIOD. A WEAK WAVE OF LOW PRESSURE WILL SCOOT BY TO OUR SOUTH TODAY BUT NOT BEFORE PUSHING SOME LIGHT SHOWER ACTIVITY NORTHWARD INTO MAINLY SOUTHEAST KENTUCKY THIS MORNING. AS THIS BATCH OF SHOWERS EXITS...MODELS INDICATE SOME BREAKS MAY DEVELOP IN THE CLOUDS AND THE ATMOSPHERE MAY DESTABILIZE A BIT OVER OUR SOUTHERN COUNTIES DURING THE AFTERNOON. WITH THIS IN MIND...ADDED A SLIGHT CHANCE OF THUNDERSTORMS ALONG AND SOUTH OF THE HAL ROGERS PARKWAY. THE FLOW IN THE LOW LEVELS WILL BACK FROM THE NORTHEAST THIS MORNING TO A SOUTHEASTERLY DIRECTION LATER TODAY INTO TONIGHT. THIS DOWNSLOPING FLOW...WHILE NOT STRONG...SHOULD HELP LESSEN RAIN CHANCES...ALTHOUGH STILL CANNOT RULE OUT A SHOWER OR TWO THROUGH THE NIGHT. MODELS THEN INDICATE THAT ANOTHER DISTURBANCE WILL PASS ACROSS THE OHIO VALLEY DURING THE DAY ON THURSDAY BRINGING ANOTHER UPTICK IN SHOWER ACTIVITY. RAIN CHANCES ON THURSDAY WILL BE HIGHEST OVER OUR WESTERN COUNTIES AND LOWEST ALONG THE WV/VA BORDERS DUE TO THE CONTINUING SOUTHEAST FLOW IN THE LOW LEVELS. A THUNDERSTORM WILL ALSO BE POSSIBLE OVER OUR WESTERN COUNTIES. RAINFALL AMOUNTS DO NOT LOOK EXCESSIVE...SO DO NOT EXPECT THIS TO CAUSE ANY WORSENING OF THE CURRENT FLOODING OR CREATE ANY NEW FLOOD PROBLEMS. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 337 AM EDT WED APR 15 2015 THE EXTENDED FORECAST PERIOD BEGINS ON THURSDAY NIGHT WITH AN ACTIVE UPPER LEVEL PATTERN IN PLACE. MAIN FEATURE OF THIS PERIOD WILL LIE WITH A CLOSED LOW PARKED OVER THE FOUR CORNERS REGION. DURING THIS PERIOD IN THE THURSDAY NIGHT THROUGH FRIDAY RANGE...WITH THE UPPER LEVEL FLOW SPLIT BETWEEN A NORTHERN STREAM AND SOUTHERN...A SERIES OF WAVES EJECT INTO THE LOWER AND MID MS VALLEY AND EVENTUALLY THE TN VALLEY. DURING THIS TIME AS WELL...ALONG THE NORTHERN STREAM...A COUPLE OF SHORTWAVES ARE MOVING THROUGH THE GREAT LAKES AND OH VALLEY REGION. THIS LOOKS TO BE PROVIDING ENOUGH LIFT IN THE MID AND UPPER LEVELS FOR SUSTAINED RAINFALL THROUGH FRIDAY BEFORE THE SUPPORT MOVES OFF TO THE EAST. THIS WILL PROVIDE A BREAK FRIDAY EVENING AND INTO SATURDAY MORNING BEFORE ANOTHER WAVE ALONG THE SOUTHERN STREAM EJECTS INTO THE LOWER AND MID MS VALLEY. WITH THIS...THE MENTIONED CLOSED LOW EJECTS EASTWARD AS WELL. THIS COMBINED WITH ANOTHER STRONGER SHORTWAVE ALONG THE NORTHERN STREAM WILL PROVIDE THE BEST CHANCE FOR AMPLE PRECIP FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY NIGHT RANGE AS A DEEP SHORTWAVE DEVELOPS IN THE PLAINS AND BEGINS TO MOVE EAST. THE TUESDAY AND TUESDAY NIGHT RANGE OF THE EXTENDED LOOKS TO BE RELATIVELY QUITE WITH MID AND UPPER LEVEL RIDGING MOVING IN. LOOKING AT THE CONSISTENCY BETWEEN THE GFS AND EURO...THEY SEEM TO BE IN DECENT AGREEMENT...THOUGH SLIGHT DIFFERENCES WITH THE STRONGER WAVE IN THE PLAINS BY SUNDAY. THE AGREEMENT MADE IT SEEM THAT A SUPER BLEND SOLUTION MAY BE SUITABLE BUT THE OBVIOUS NEED TO KEEP FRIDAY NIGHT DRY INTO SATURDAY MORNING AS THIS WAS SHOWN IN THE GFS AND EURO...WAS LEFT OUT AND THE BLEND HAD CHANCE POPS. THIS WAS COLLABORATED WITH NEIGHBORING OFFICES. IN ADDITION...DUE TO THE DISTANCE IN THE EXTENDED...THE SUPER BLEND WAS SUITABLE BUT THE POPS FOR SUNDAY THROUGH MONDAY COULD EASILY BE PUSHED TO CATEGORICAL BASED UPON THE CONSISTENCY OF THE RUNS AND WHAT THE MODELS ARE ADVERTISING DURING THIS TIME FRAME. CLOSER TO THE SURFACE...A WEAK REMNANT BOUNDARY STRETCHING INTO KENTUCKY WITH THE MENTIONED DISTURBANCES WILL KEEP THE THREAT OF SHOWERS AND THUNDERSTORMS OVER THE AREA BUT NO REAL FORCING OR STRONG INSTABILITY FOR A CONCERN OF AN ORGANIZED AREA OF RAINFALL DURING THE THURSDAY NIGHT THROUGH FRIDAY TIME FRAME AND HAVE KEPT POPS AT SLIGHT CHANCE OR MINIMAL. WEAK MID LEVEL RIDGING WILL KEEP A BREAK IN THE PRECIP OVER THE AREA FRIDAY NIGHT INTO SATURDAY BEFORE THE NEXT FRONT AND SURGE OF MOISTURE MOVES INTO THE AREA LATE SATURDAY AND SATURDAY NIGHT. AS THE MENTIONED UPPER LOW MOVES EAST INTO THE PLAINS...SURFACE LOW PRESSURE DEVELOPS IN THE PLAINS AND A SURGE OF MOISTURE BEHIND A STRENGTHENING WARM FRONT MOVES NORTHEAST INTO THE TN AND OH VALLEYS BY SUNDAY AND INTO SUNDAY NIGHT. THIS LOOKS TO BE A STRONG SURGE OR MOISTURE WITH PWATS REACHING 1.50 IN SOME LOCATIONS ALONG WITH AN ELEMENT THAT HAS NOT BEEN NOTICEABLY PRESENT FROM THE LAST EVENT...A SIZABLE AMOUNT OF INSTABILITY. BASED ON THE CONTINUING WET PATTERN...THE MAIN CONCERN HERE WILL BE HEAVY RAINFALL BUT THE AMOUNT OF DYNAMICS AND INSTABILITY RAISE A SEVERE WEATHER CONCERN HERE. A PATTERN SUCH AS THIS CAN CHANGE RAPIDLY AS WELL AND AS SUCH SOME UNCERTAINTIES ARE PRESENT. FOR NOW...WILL MENTION THE FLOOD THREAT IN THE HWO. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 225 PM EDT WED APR 15 2015 SCATTERED LIGHT SHOWERS CONTINUE TO DRIFT THROUGH EAST KENTUCKY THIS AFTERNOON...BUT COVERAGE IS CERTAINLY ON THE WANE. WITH THIS...VISIBILITIES HAVE STAYED UP...EVEN IN THE RAIN...WHILE CIGS HAVE BEEN MOSTLY LIFR...BUT RATHER VARIABLE. THE LOW LEVEL FLOW WILL SHIFT TO A MORE SOUTHEASTERLY DIRECTION TONIGHT AND THIS DRIER...DOWNSLOPING FLOW WILL HELP TO SCOUR OUT THE LOWER CIGS. AS SUCH...EXPECT A RETURN TO MVFR OR VFR CONDITIONS AT MOST LOCATIONS DURING THE EARLY EVENING WITH VFR EXPECTED THROUGH THE MORNING...THURSDAY. AS SHOWERS WILL BE AROUND HAVE KEPT VCSH IN ALL THE TAFS THROUGH THE PERIOD...WHILE WINDS ARE EXPECTED TO BE LIGHT AND VARIABLE. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...ABE LONG TERM...SHALLENBERGER AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1104 AM EDT WED APR 15 2015 .UPDATE... ISSUED AT 1105 AM EDT WED APR 15 2015 14Z SFC ANALYSIS SHOWS AN INVERTED TROUGH LYING THROUGH EASTERN KENTUCKY FROM AN AREA OF LOW PRESSURE OVER THE LOWER MISSISSIPPI VALLEY. ON RADAR...SHOWERS...MAINLY LIGHT...CONTINUE TO SPREAD NORTHEAST THROUGH EASTERN KENTUCKY. CLOUDS COVER THE AREA WITH TEMPERATURES OFF TO A SLOW START. CURRENTLY...WITH EAST TO NORTHEAST WINDS OF 5 TO 10 MPH...TEMPERATURES ARE IN THE LOW TO MID 50S NORTH AND NEAR 60 DEGREES IN THE FAR SOUTH. DEWPOINTS VARY FROM THE LOW 40S IN THE FAR NORTH TO MID AND UPPER 50S IN THE FAR SOUTH. THE LATEST HRRR AND NAM12 GUIDANCE SUGGESTS THAT THE RAIN LINGERS MORE OVER THE WESTERN AND CENTRAL PARTS OF THE CWA THROUGH MID AFTERNOON THAN WE HAD INITIALLY REPRESENTED IN THE GRIDS. ACCORDINGLY...HAVE TWEAKED THE POP AND WEATHER GRIDS TO REFLECT THIS CHANGE...ALSO KEEPING THE SMALL POTENTIAL FOR A THUNDERSTORM THIS AFTERNOON. FINALLY...SLOWED THE RISE OF TEMPERATURES THROUGH EARLY AFTERNOON DUE TO THE CLOUDS AND PCPN. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. AN UPDATED SET OF ZONE WILL BE ISSUED SHORTLY...AS WELL. UPDATE ISSUED AT 640 AM EDT WED APR 15 2015 RAIN CONTINUES TO PROGRESS UP THE CUMBERLAND VALLEY AND HAVE INCREASED POPS FURTHER OVER SOUTHEAST KENTUCKY. STILL A LITTLE UNSURE HOW FAR TO THE NORTH AND WEST THE RAIN WILL GET CONSIDERING DRIER AIR IN PLACE BUT THE LATEST HRRR BRINGS THE RAIN AS FAR WEST AS JACKSON AND THAT SEEMS REASONABLE. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 337 AM EDT WED APR 15 2015 MOIST SOUTHWEST FLOW ALOFT WILL REMAIN IN PLACE THROUGH THE SHORT TERM PERIOD. A WEAK WAVE OF LOW PRESSURE WILL SCOOT BY TO OUR SOUTH TODAY BUT NOT BEFORE PUSHING SOME LIGHT SHOWER ACTIVITY NORTHWARD INTO MAINLY SOUTHEAST KENTUCKY THIS MORNING. AS THIS BATCH OF SHOWERS EXITS...MODELS INDICATE SOME BREAKS MAY DEVELOP IN THE CLOUDS AND THE ATMOSPHERE MAY DESTABILIZE A BIT OVER OUR SOUTHERN COUNTIES DURING THE AFTERNOON. WITH THIS IN MIND...ADDED A SLIGHT CHANCE OF THUNDERSTORMS ALONG AND SOUTH OF THE HAL ROGERS PARKWAY. THE FLOW IN THE LOW LEVELS WILL BACK FROM THE NORTHEAST THIS MORNING TO A SOUTHEASTERLY DIRECTION LATER TODAY INTO TONIGHT. THIS DOWNSLOPING FLOW...WHILE NOT STRONG...SHOULD HELP LESSEN RAIN CHANCES...ALTHOUGH STILL CANNOT RULE OUT A SHOWER OR TWO THROUGH THE NIGHT. MODELS THEN INDICATE THAT ANOTHER DISTURBANCE WILL PASS ACROSS THE OHIO VALLEY DURING THE DAY ON THURSDAY BRINGING ANOTHER UPTICK IN SHOWER ACTIVITY. RAIN CHANCES ON THURSDAY WILL BE HIGHEST OVER OUR WESTERN COUNTIES AND LOWEST ALONG THE WV/VA BORDERS DUE TO THE CONTINUING SOUTHEAST FLOW IN THE LOW LEVELS. A THUNDERSTORM WILL ALSO BE POSSIBLE OVER OUR WESTERN COUNTIES. RAINFALL AMOUNTS DO NOT LOOK EXCESSIVE...SO DO NOT EXPECT THIS TO CAUSE ANY WORSENING OF THE CURRENT FLOODING OR CREATE ANY NEW FLOOD PROBLEMS. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 337 AM EDT WED APR 15 2015 THE EXTENDED FORECAST PERIOD BEGINS ON THURSDAY NIGHT WITH AN ACTIVE UPPER LEVEL PATTERN IN PLACE. MAIN FEATURE OF THIS PERIOD WILL LIE WITH A CLOSED LOW PARKED OVER THE FOUR CORNERS REGION. DURING THIS PERIOD IN THE THURSDAY NIGHT THROUGH FRIDAY RANGE...WITH THE UPPER LEVEL FLOW SPLIT BETWEEN A NORTHERN STREAM AND SOUTHERN...A SERIES OF WAVES EJECT INTO THE LOWER AND MID MS VALLEY AND EVENTUALLY THE TN VALLEY. DURING THIS TIME AS WELL...ALONG THE NORTHERN STREAM...A COUPLE OF SHORTWAVES ARE MOVING THROUGH THE GREAT LAKES AND OH VALLEY REGION. THIS LOOKS TO BE PROVIDING ENOUGH LIFT IN THE MID AND UPPER LEVELS FOR SUSTAINED RAINFALL THROUGH FRIDAY BEFORE THE SUPPORT MOVES OFF TO THE EAST. THIS WILL PROVIDE A BREAK FRIDAY EVENING AND INTO SATURDAY MORNING BEFORE ANOTHER WAVE ALONG THE SOUTHERN STREAM EJECTS INTO THE LOWER AND MID MS VALLEY. WITH THIS...THE MENTIONED CLOSED LOW EJECTS EASTWARD AS WELL. THIS COMBINED WITH ANOTHER STRONGER SHORTWAVE ALONG THE NORTHERN STREAM WILL PROVIDE THE BEST CHANCE FOR AMPLE PRECIP FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY NIGHT RANGE AS A DEEP SHORTWAVE DEVELOPS IN THE PLAINS AND BEGINS TO MOVE EAST. THE TUESDAY AND TUESDAY NIGHT RANGE OF THE EXTENDED LOOKS TO BE RELATIVELY QUITE WITH MID AND UPPER LEVEL RIDGING MOVING IN. LOOKING AT THE CONSISTENCY BETWEEN THE GFS AND EURO...THEY SEEM TO BE IN DECENT AGREEMENT...THOUGH SLIGHT DIFFERENCES WITH THE STRONGER WAVE IN THE PLAINS BY SUNDAY. THE AGREEMENT MADE IT SEEM THAT A SUPER BLEND SOLUTION MAY BE SUITABLE BUT THE OBVIOUS NEED TO KEEP FRIDAY NIGHT DRY INTO SATURDAY MORNING AS THIS WAS SHOWN IN THE GFS AND EURO...WAS LEFT OUT AND THE BLEND HAD CHANCE POPS. THIS WAS COLLABORATED WITH NEIGHBORING OFFICES. IN ADDITION...DUE TO THE DISTANCE IN THE EXTENDED...THE SUPER BLEND WAS SUITABLE BUT THE POPS FOR SUNDAY THROUGH MONDAY COULD EASILY BE PUSHED TO CATEGORICAL BASED UPON THE CONSISTENCY OF THE RUNS AND WHAT THE MODELS ARE ADVERTISING DURING THIS TIME FRAME. CLOSER TO THE SURFACE...A WEAK REMNANT BOUNDARY STRETCHING INTO KENTUCKY WITH THE MENTIONED DISTURBANCES WILL KEEP THE THREAT OF SHOWERS AND THUNDERSTORMS OVER THE AREA BUT NO REAL FORCING OR STRONG INSTABILITY FOR A CONCERN OF AN ORGANIZED AREA OF RAINFALL DURING THE THURSDAY NIGHT THROUGH FRIDAY TIME FRAME AND HAVE KEPT POPS AT SLIGHT CHANCE OR MINIMAL. WEAK MID LEVEL RIDGING WILL KEEP A BREAK IN THE PRECIP OVER THE AREA FRIDAY NIGHT INTO SATURDAY BEFORE THE NEXT FRONT AND SURGE OF MOISTURE MOVES INTO THE AREA LATE SATURDAY AND SATURDAY NIGHT. AS THE MENTIONED UPPER LOW MOVES EAST INTO THE PLAINS...SURFACE LOW PRESSURE DEVELOPS IN THE PLAINS AND A SURGE OF MOISTURE BEHIND A STRENGTHENING WARM FRONT MOVES NORTHEAST INTO THE TN AND OH VALLEYS BY SUNDAY AND INTO SUNDAY NIGHT. THIS LOOKS TO BE A STRONG SURGE OR MOISTURE WITH PWATS REACHING 1.50 IN SOME LOCATIONS ALONG WITH AN ELEMENT THAT HAS NOT BEEN NOTICEABLY PRESENT FROM THE LAST EVENT...A SIZABLE AMOUNT OF INSTABILITY. BASED ON THE CONTINUING WET PATTERN...THE MAIN CONCERN HERE WILL BE HEAVY RAINFALL BUT THE AMOUNT OF DYNAMICS AND INSTABILITY RAISE A SEVERE WEATHER CONCERN HERE. A PATTERN SUCH AS THIS CAN CHANGE RAPIDLY AS WELL AND AS SUCH SOME UNCERTAINTIES ARE PRESENT. FOR NOW...WILL MENTION THE FLOOD THREAT IN THE HWO. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 640 AM EDT WED APR 15 2015 ANOTHER BATCH OF SHOWERS WILL RIDE NORTHEAST OUT OF TENNESSEE INTO MUCH OF SOUTHEAST KENTUCKY AFFECTING SME...LOZ...JKL AND SJS THIS MORNING. CONDITIONS SHOULD STAY AT OR DROP TO IFR AS THE RAIN FALLS. EXPECT THE SHOWERS TO EXIT TO OUR EAST DURING THE AFTERNOON ALTHOUGH CANNOT RULE OUT A STRAY SHOWER OR EVEN A THUNDERSTORM DURING THE AFTERNOON. THE LOW LEVEL FLOW WILL SHIFT TO A MORE SOUTHEASTERLY DIRECTION TONIGHT AND THIS DRIER...DOWNSLOPING FLOW WILL HELP TO SCOUR OUT THE LOWER CEILINGS. AS SUCH...EXPECT A RETURN TO VFR CONDITIONS AT ALL LOCATIONS DURING THE AFTERNOON AND EARLY EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...ABE LONG TERM...SHALLENBERGER AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
640 AM EDT WED APR 15 2015 .UPDATE... ISSUED AT 640 AM EDT WED APR 15 2015 RAIN CONTINUES TO PROGRESS UP THE CUMBERLAND VALLEY AND HAVE INCREASED POPS FURTHER OVER SOUTHEAST KENTUCKY. STILL A LITTLE UNSURE HOW FAR TO THE NORTH AND WEST THE RAIN WILL GET CONSIDERING DRIER AIR IN PLACE BUT THE LATEST HRRR BRINGS THE RAIN AS FAR WEST AS JACKSON AND THAT SEEMS REASONABLE. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 337 AM EDT WED APR 15 2015 MOIST SOUTHWEST FLOW ALOFT WILL REMAIN IN PLACE THROUGH THE SHORT TERM PERIOD. A WEAK WAVE OF LOW PRESSURE WILL SCOOT BY TO OUR SOUTH TODAY BUT NOT BEFORE PUSHING SOME LIGHT SHOWER ACTIVITY NORTHWARD INTO MAINLY SOUTHEAST KENTUCKY THIS MORNING. AS THIS BATCH OF SHOWERS EXITS...MODELS INDICATE SOME BREAKS MAY DEVELOP IN THE CLOUDS AND THE ATMOSPHERE MAY DESTABILIZE A BIT OVER OUR SOUTHERN COUNTIES DURING THE AFTERNOON. WITH THIS IN MIND...ADDED A SLIGHT CHANCE OF THUNDERSTORMS ALONG AND SOUTH OF THE HAL ROGERS PARKWAY. THE FLOW IN THE LOW LEVELS WILL BACK FROM THE NORTHEAST THIS MORNING TO A SOUTHEASTERLY DIRECTION LATER TODAY INTO TONIGHT. THIS DOWNSLOPING FLOW...WHILE NOT STRONG...SHOULD HELP LESSEN RAIN CHANCES...ALTHOUGH STILL CANNOT RULE OUT A SHOWER OR TWO THROUGH THE NIGHT. MODELS THEN INDICATE THAT ANOTHER DISTURBANCE WILL PASS ACROSS THE OHIO VALLEY DURING THE DAY ON THURSDAY BRINGING ANOTHER UPTICK IN SHOWER ACTIVITY. RAIN CHANCES ON THURSDAY WILL BE HIGHEST OVER OUR WESTERN COUNTIES AND LOWEST ALONG THE WV/VA BORDERS DUE TO THE CONTINUING SOUTHEAST FLOW IN THE LOW LEVELS. A THUNDERSTORM WILL ALSO BE POSSIBLE OVER OUR WESTERN COUNTIES. RAINFALL AMOUNTS DO NOT LOOK EXCESSIVE...SO DO NOT EXPECT THIS TO CAUSE ANY WORSENING OF THE CURRENT FLOODING OR CREATE ANY NEW FLOOD PROBLEMS. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 337 AM EDT WED APR 15 2015 THE EXTENDED FORECAST PERIOD BEGINS ON THURSDAY NIGHT WITH AN ACTIVE UPPER LEVEL PATTERN IN PLACE. MAIN FEATURE OF THIS PERIOD WILL LIE WITH A CLOSED LOW PARKED OVER THE FOUR CORNERS REGION. DURING THIS PERIOD IN THE THURSDAY NIGHT THROUGH FRIDAY RANGE...WITH THE UPPER LEVEL FLOW SPLIT BETWEEN A NORTHERN STREAM AND SOUTHERN...A SERIES OF WAVES EJECT INTO THE LOWER AND MID MS VALLEY AND EVENTUALLY THE TN VALLEY. DURING THIS TIME AS WELL...ALONG THE NORTHERN STREAM...A COUPLE OF SHORTWAVES ARE MOVING THROUGH THE GREAT LAKES AND OH VALLEY REGION. THIS LOOKS TO BE PROVIDING ENOUGH LIFT IN THE MID AND UPPER LEVELS FOR SUSTAINED RAINFALL THROUGH FRIDAY BEFORE THE SUPPORT MOVES OFF TO THE EAST. THIS WILL PROVIDE A BREAK FRIDAY EVENING AND INTO SATURDAY MORNING BEFORE ANOTHER WAVE ALONG THE SOUTHERN STREAM EJECTS INTO THE LOWER AND MID MS VALLEY. WITH THIS...THE MENTIONED CLOSED LOW EJECTS EASTWARD AS WELL. THIS COMBINED WITH ANOTHER STRONGER SHORTWAVE ALONG THE NORTHERN STREAM WILL PROVIDE THE BEST CHANCE FOR AMPLE PRECIP FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY NIGHT RANGE AS A DEEP SHORTWAVE DEVELOPS IN THE PLAINS AND BEGINS TO MOVE EAST. THE TUESDAY AND TUESDAY NIGHT RANGE OF THE EXTENDED LOOKS TO BE RELATIVELY QUITE WITH MID AND UPPER LEVEL RIDGING MOVING IN. LOOKING AT THE CONSISTENCY BETWEEN THE GFS AND EURO...THEY SEEM TO BE IN DECENT AGREEMENT...THOUGH SLIGHT DIFFERENCES WITH THE STRONGER WAVE IN THE PLAINS BY SUNDAY. THE AGREEMENT MADE IT SEEM THAT A SUPER BLEND SOLUTION MAY BE SUITABLE BUT THE OBVIOUS NEED TO KEEP FRIDAY NIGHT DRY INTO SATURDAY MORNING AS THIS WAS SHOWN IN THE GFS AND EURO...WAS LEFT OUT AND THE BLEND HAD CHANCE POPS. THIS WAS COLLABORATED WITH NEIGHBORING OFFICES. IN ADDITION...DUE TO THE DISTANCE IN THE EXTENDED...THE SUPER BLEND WAS SUITABLE BUT THE POPS FOR SUNDAY THROUGH MONDAY COULD EASILY BE PUSHED TO CATEGORICAL BASED UPON THE CONSISTENCY OF THE RUNS AND WHAT THE MODELS ARE ADVERTISING DURING THIS TIME FRAME. CLOSER TO THE SURFACE...A WEAK REMNANT BOUNDARY STRETCHING INTO KENTUCKY WITH THE MENTIONED DISTURBANCES WILL KEEP THE THREAT OF SHOWERS AND THUNDERSTORMS OVER THE AREA BUT NO REAL FORCING OR STRONG INSTABILITY FOR A CONCERN OF AN ORGANIZED AREA OF RAINFALL DURING THE THURSDAY NIGHT THROUGH FRIDAY TIME FRAME AND HAVE KEPT POPS AT SLIGHT CHANCE OR MINIMAL. WEAK MID LEVEL RIDGING WILL KEEP A BREAK IN THE PRECIP OVER THE AREA FRIDAY NIGHT INTO SATURDAY BEFORE THE NEXT FRONT AND SURGE OF MOISTURE MOVES INTO THE AREA LATE SATURDAY AND SATURDAY NIGHT. AS THE MENTIONED UPPER LOW MOVES EAST INTO THE PLAINS...SURFACE LOW PRESSURE DEVELOPS IN THE PLAINS AND A SURGE OF MOISTURE BEHIND A STRENGTHENING WARM FRONT MOVES NORTHEAST INTO THE TN AND OH VALLEYS BY SUNDAY AND INTO SUNDAY NIGHT. THIS LOOKS TO BE A STRONG SURGE OR MOISTURE WITH PWATS REACHING 1.50 IN SOME LOCATIONS ALONG WITH AN ELEMENT THAT HAS NOT BEEN NOTICEABLY PRESENT FROM THE LAST EVENT...A SIZABLE AMOUNT OF INSTABILITY. BASED ON THE CONTINUING WET PATTERN...THE MAIN CONCERN HERE WILL BE HEAVY RAINFALL BUT THE AMOUNT OF DYNAMICS AND INSTABILITY RAISE A SEVERE WEATHER CONCERN HERE. A PATTERN SUCH AS THIS CAN CHANGE RAPIDLY AS WELL AND AS SUCH SOME UNCERTAINTIES ARE PRESENT. FOR NOW...WILL MENTION THE FLOOD THREAT IN THE HWO. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 640 AM EDT WED APR 15 2015 ANOTHER BATCH OF SHOWERS WILL RIDE NORTHEAST OUT OF TENNESSEE INTO MUCH OF SOUTHEAST KENTUCKY AFFECTING SME...LOZ...JKL AND SJS THIS MORNING. CONDITIONS SHOULD STAY AT OR DROP TO IFR AS THE RAIN FALLS. EXPECT THE SHOWERS TO EXIT TO OUR EAST DURING THE AFTERNOON ALTHOUGH CANNOT RULE OUT A STRAY SHOWER OR EVEN A THUNDERSTORM DURING THE AFTERNOON. THE LOW LEVEL FLOW WILL SHIFT TO A MORE SOUTHEASTERLY DIRECTION TONIGHT AND THIS DRIER...DOWNSLOPING FLOW WILL HELP TO SCOUR OUT THE LOWER CEILINGS. AS SUCH...EXPECT A RETURN TO VFR CONDITIONS AT ALL LOCATIONS DURING THE AFTERNOON AND EARLY EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ABE SHORT TERM...ABE LONG TERM...SHALLENBERGER AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
159 AM EDT WED APR 15 2015 .UPDATE... ISSUED AT 159 AM EDT WED APR 15 2015 SEVERAL ADJUSTMENTS WERE MADE TO THE PUBLIC GRIDS IN CONJUNCTION WITH THE AVIATION UPDATES. THE BIG CHANGE WAS TO INCREASE POPS OVER SOUTHEAST KENTUCKY THIS MORNING AS ANOTHER BATCH OF SHOWERS HEADS TOWARDS OUR AREA FROM TENNESSEE. THIS DOES NOT LOOK HEAVY AND SHOULD NOT WORSEN ANY FLOODING OR CREATE NEW PROBLEMS...BUT THE RAIN SHOULD MEASURE FOR MANY LOCATIONS EAST OF THE DANIEL BOONE NATIONAL FORECAST ACCORDING TO NEAR TERM MODELS AND RADAR TRENDS. UPDATE ISSUED AT 840 PM EDT TUE APR 14 2015 HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND TRENDS. RECENT RUNS OF THE NAM12...HRRR AND RAP CONTINUE TO POINT TOWARD SOME RAIN POSSIBLY MOVING INTO SOUTHERN AND SOUTHEASTERN LOCATIONS LATER TONIGHT. WE WILL EVALUATE THE NEXT RUNS OF THE 0Z NAM...AS WELL AS HRRR AND RAP FOR THE POSSIBLE NEED TO INCREASE POPS NEAR THE TN AND VA BORDERS LATE TONIGHT. OVERALL...NO SIGNIFICANT CHANGES WERE NEEDED ATTM. UPDATE ISSUED AT 345 PM EDT TUE APR 14 2015 GIVEN THAT MUCH OF THE RAIN HAS SUBSIDED ACROSS THE REGION WE HAVE DROPPED THE FLOOD WATCH FOR THE REGION. ONGOING FLOODING WILL BE COVERED BY FLOOD WARNINGS AND ADVISORIES. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 315 PM EDT TUE APR 14 2015 SURFACE ANALYSIS SHOWS A BROADER AREA OF SURFACE LOW PRESSURE CENTERED JUST TO THE SOUTH ACROSS EASTERN TENNESSEE THIS AFTERNOON. THIS ALONG WITH A FRONTAL BOUNDARY HAS BEEN THE FOCAL POINT OF LIFT FOR THE RAINFALL THAT HAS OCCURRED TODAY. LATEST WSR- 88D RADAR AT 3 PM DOES INDICATE THAT MUCH OF OF THE HEAVIER RAINFALL HAS WANED THIS AFTERNOON. THIS AREA OF LOW PRESSURE IS EXPECTED TO PROGRESS EAST INTO THE CAROLINAS AS WE MOVE TONIGHT ALONG WITH THE RAINFALL. THE QUESTION THAT REMAINS FOR OVERNIGHT HOURS IS WHAT WILL HAPPEN WITH YET ANOTHER UPPER LEVEL WAVE TRACKING NORTHEAST OUT OF THE LOWER MISSISSIPPI RIVER VALLEY. SOME OF THE MESOSCALE MODELS SUCH AS THE HRRR AND RAP WOULD SUGGEST WE WILL GET AT LEAST CLIPPED BY THIS AREA OF RAIN ASSOCIATED WITH THE WAVE. RIGHT NOW WE ARE CARRYING SLIGHT TO CHANCE POPS WITH HIGHER POPS ACROSS SOUTHEAST KENTUCKY. THESE POPS COULD NEED TO BE HIGHER LATE EVENING INTO THE OVERNIGHT DEPENDING ON THE PROPAGATION OF THIS WAVE OF ENERGY. UNDER THIS GENERAL SOUTHWEST FLOW ALOFT WILL BRING YET ANOTHER UPPER LEVEL SHORTWAVE AS WE MOVE INTO LATER WEDNESDAY INTO WEDNESDAY NIGHT. THIS WILL BRING ANOTHER ROUND INCREASED ROUND OF SHOWERS FROM SOUTHWEST TO NORTHEAST OVERNIGHT WEDNESDAY AS THIS WAVE TRACKS NORTHEAST AND DIFFLUENCE ALOFT IN PLACE. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 335 PM EDT TUE APR 14 2015 THE UPPER LEVEL PATTERN SHOWS NORTHERN STREAM FLOW SITUATED ALONG THE CANADIAN/US BORDER THROUGH THE EXTENDED PERIOD...WHILE THE EASTERN US IS DOMINATED BY RIDGING AND THE WESTERN US IS DOMINATED BY A SPLIT FLOW WITH A CUT OFF LOW IN THE SOUTHERN STREAM. A SERIES OF DISTURBANCES WILL EJECT OUT OF THE SOUTHERN STREAM AND PASS THROUGH THE TN AND OH VALLEYS DURING THE LATTER HALF OF THE WORK WEEK...BRINGING PRECIPITATION...POSSIBLY HEAVY AT TIMES. SUNDAY...THE CUT OFF LOW IS PROGGED TO LIFT OUT OF THE SRN STREAM AND MERGE WITH A NORTHERN STREAM UL TROUGH WHICH ENDS UP TURNING INTO A LARGE ROBUST SYSTEM. THIS SYSTEM IS PROGGED TO SPREAD PRECIPITATION OVER THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY SOUTHWARD ACROSS OUR REGION AND INTO THE SOUTHEASTERN US FROM SUNDAY AFTERNOON THROUGH LATE MONDAY NIGHT. THE UL PATTERN IS THEN DOMINATED BY THE UL TROUGH WHICH SLOWLY MOVES ALONG THE US/CANADIAN BORDER...NORTH OF THE GREAT LAKES...THROUGH THE END OF THE EXTENDED PERIOD. THIS WILL ALLOW FOR TEMPERATURES TO DROP BACK DOWN TO SEASONABLE LEVELS NEXT TUES/WED AND POSSIBLY BRING A SHORT BREAK TO THE WET WEATHER. AT THE SFC...THE UL DISTURBANCES WILL BRING CONTINUED CHANCES FOR RAIN THURSDAY THROUGH LATE MONDAY. THERE MAY BE MOMENTARY BREAKS IN THE RAIN ON SATURDAY BUT OVERALL THIS WILL BE ANOTHER WET PERIOD WITH ABOVE AVERAGE RAINFALL. SOUTHERLY FLOW WILL ALSO PERSIST...USHERING IN WARM MOIST AIR...WHICH ENHANCES THE RAIN POTENTIAL THROUGH THE PERIOD. MODEL SOUNDINGS SHOW PW VALUES FLUCTUATE BETWEEN 1.0" AND 1.4" DURING THIS PERIOD...WHICH IS WELL ABOVE THE 2 STANDARD DEVIATIONS ABOVE NORMAL. BY LATE MONDAY/EARLY TUESDAY...THE UL TROUGH SHOULD FINALLY PUSH EAST...PROVIDING ANOTHER BREAK IN RAINFALL BY TUESDAY AFTERNOON. THERE ARE SUBSTANTIAL DIFFERENCES BETWEEN THE GFS AND ECMWF...ESPECIALLY DURING THE WEEKEND PERIOD AND BEYOND. SO HAVE STUCK CLOSE TO THE CR SUPERBLEND FOR THE MAJORITY OF THE EXTENDED PERIOD. ALSO KEPT SLIGHT CHANCE FOR THUNDER THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 159 AM EDT WED APR 15 2015 DIFFICULT FORECAST DUE TO VARIABLE CEILINGS. IN GENERAL... LOWERING FLIGHT CONDITIONS ARE ANTICIPATED OVER THE NEXT SEVERAL HOURS AS ANOTHER BATCH OF SHOWERS IS POISED TO RIDE NORTHEAST OUT OF TENNESSEE INTO MUCH OF SOUTHEAST KENTUCKY. THE SHOWERS SHOULD EXIT TO OUR EAST DURING THE AFTERNOON FOLLOWED BY A SHIFT IN LOW LEVEL FLOW TO A MORE SOUTHEASTERLY DIRECTION. THIS DRIER... DOWNSLOPING FLOW WILL HELP TO SCOUR OUT THE LOWER CEILINGS. AS SUCH...EXPECT A RETURN TO VFR CONDITIONS AT ALL LOCATIONS DURING THE AFTERNOON AND EARLY EVENING. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP/ABE SHORT TERM...DJ LONG TERM...JVM AVIATION...ABE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
138 PM EDT WED APR 15 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 316 AM EDT WED APR 15 2015 DRY AND BREEZY CONDITIONS TODAY MAY INCREASE FIRE DANGER ACROSS PORTIONS OF SOUTHERN LOWER MICHIGAN. AFTER SHOWERS ON THURSDAY...A WARM AND DRY STRETCH FOR FRIDAY AND SATURDAY LOOKS LIKELY. SOME RAIN RETURNS FOR LATER SUNDAY. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 316 AM EDT WED APR 15 2015 TWO MAIN ISSUES TO ADDRESS IN THE SHORT TERM. FIRST...BREEZY CONDITIONS TODAY WILL INCREASE A RISK FOR SPREADABLE FIRES MAINLY FOR DRY FUELS LIKE GRASS AND TREE LITTER AND PARTICULARLY FOR SOUTH CENTRAL LOWER MI WHICH HAS BEEN DRYER THAN OTHER AREAS. PLEASE SEE THE FIRE WEATHER DISCUSSION FOR SPECIFICS. SECONDLY...THURSDAY LOOKS TO BE A SHOWERY DAY WITH A LOW RISK FOR A THUNDERSTORM. OVERALL...MODELS ARE ZONING IN ON A SHOWERY SETUP FOR THURSDAY ACROSS MUCH OF THE CWA NOW WITH A WING OF WARM AIR ADVECTION MOVING IN ALBEIT WITH WEAK FORCING AT THE SFC AND ALOFT. GFS AND ECMWF ARE SHOWING AT LEAST SOME SFC CONVERGENCE ALONG/EAST OF A LINE FROM SOUTH HAVEN TO GRR TO MT. PLEASANT DURING THE DAY. THIS IS WHERE MODEL QPF IS HIGHEST. INCREASED POPS A BIT FOR THIS EVENT ACROSS MUCH OF THE CWA GIVEN MODELS LOCKING IN ON THIS SCENARIO NOW. THE RISK FOR THUNDER STILL LOOKS LOW TO ME AND I CONSIDERED REMOVING MENTION OF IT ALTOGETHER...BASED ON NO CAPE TO BE FOUND ON ANY MODEL SOUNDINGS. NEVERTHELESS...GIVEN THE TIMING OF THIS SYSTEM I SUPPOSE IT IS POSSIBLE TO GET A RUMBLE OF THUNDER IN THE AFTERNOON AND EVENING. WITH THE CLOUDS AND SHOWERS THURSDAY WILL NOT BE AS WARM...HIGHS IN THE UPPER 50S TO LOW 60S. EASTERLY WINDS TODAY ARE ALREADY UNDERWAY. USED THE HRRR THROUGH EARLY AFTERNOON FOR THE WINDS AND THEN A BLEND OF THE HI-RES WRF ARW AND A SEPARATE MEDIUM RANGE MODEL BLEND FOR THE REST OF THE SHORT TERM. LOOKS LIKE WINDS COULD STILL GUST IN THE 20-25 MPH RANGE AT TIMES TODAY. FRIDAY LOOKS REALLY NICE. BUMPED HIGHS UP FOR MOST LOCATIONS TO 70. A LIGHT SOUTHWESTERLY WIND DURING THE AFTERNOON SHOULD KEEP LAKESHORE AREAS FROM HOLLAND TO THE NORTH SEVERAL DEGREES COOLER. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 316 AM EDT WED APR 15 2015 MODEL CONSISTENCY IS GOOD THROUGH THE PERIOD WITH THE MAIN UPSHOT BEING THAT RAIN MOVES IN ON SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER MICHIGAN. THE LOW BECOMES VERTICALLY STACKED NORTH OF LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER MICHIGAN ON TUESDAY. GIVEN WET BULB ZERO HEIGHTS CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE WET SNOW ACROSS AT LEAST THE NORTHERN ZONES AT TIMES ON TUESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 138 PM EDT WED APR 15 2015 GUSTY EAST WINDS WILL CONTINUE AT ALL TAF SITES IN WRN MICHIGAN THROUGH THIS EVENING AS NEXT STORM SYSTEM APPROACHES. VERTICAL PROFILES OF MOISTURE SUGGEST A RAPID LOWERING OF CEILINGS AFTER MIDNIGHT...WITH RAIN CHANCES INCREASING TOWARD MORNING. SMALL AMOUNTS OF ELEVATED CAPE AND INSTABILITY MOVE THROUGH AROUND DAYBREAK TOMORROW...BUT WILL LEAVE THUNDER OUT OF THE TAFS FOR NOW. && .MARINE... ISSUED AT 1104 AM EDT WED APR 15 2015 OFFSHORE FLOW WILL ACT TO KEEP WAVE HEIGHTS TO A MINIMUM. GUSTS OVER 20 KNOTS LIKELY. WINDS WILL DECREASE SOMEWHAT TONIGHT AS WE LOSE THE MIXING. WINDS WILL THEN LARGELY REMAIN UNDER 20 KNOTS THROUGH THURSDAY NIGHT. && .FIRE WEATHER... ISSUED AT 316 AM EDT WED APR 15 2015 BREEZY EASTERLY WINDS 10-15 MPH GUSTING UP TO 25...ALONG WITH HIGHS IN THE MID TO UPPER 60S AND MIN RH READINGS AROUND 20% OR EVEN LOWER IN PLACES WILL LEAD TO ELEVATED FIRE DANGER MAINLY FOR ESPECIALLY SOUTH CENTRAL LOWER MICHIGAN. THIS REGION HAS NOT RECEIVED AS MUCH RAIN LATELY SO THE DRY FUELS LIKE GRASSES AND TREE LITTER ARE MORE PREVALENT. PERSONS WITH BURN INTERESTS NEED TO MONITOR FIRES CLOSELY TO PREVENT SPREADING GIVEN THE VERY DRY CONDITIONS EXPECTED TODAY WITH BREEZES PICKING UP LATE THIS MORNING AND AFTERNOON. && .HYDROLOGY... ISSUED AT 245 PM EDT TUE APR 14 2015 DRY WEATHER THROUGH TODAY... THEN A CHANCE OF RAIN ON THURSDAY. EXPECTED PRECIPITATION AMOUNTS ARE VERY LOW IN THE MAPLE RIVER BASIN AND ZERO IN THE OTHER TWO BASINS CURRENTLY UNDER THE ADVISORY. THIS WILL ALLOW THOSE RIVERS TO FALL BELOW BANKFULL OVER THE NEXT DAY OR TWO. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...HOVING SHORT TERM...HOVING LONG TERM...OSTUNO AVIATION...MWS FIRE WEATHER...HOVING HYDROLOGY...CAS MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1113 AM EDT WED APR 15 2015 LATEST UPDATE... MARINE .SYNOPSIS... ISSUED AT 316 AM EDT WED APR 15 2015 DRY AND BREEZY CONDITIONS TODAY MAY INCREASE FIRE DANGER ACROSS PORTIONS OF SOUTHERN LOWER MICHIGAN. AFTER SHOWERS ON THURSDAY...A WARM AND DRY STRETCH FOR FRIDAY AND SATURDAY LOOKS LIKELY. SOME RAIN RETURNS FOR LATER SUNDAY. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 316 AM EDT WED APR 15 2015 TWO MAIN ISSUES TO ADDRESS IN THE SHORT TERM. FIRST...BREEZY CONDITIONS TODAY WILL INCREASE A RISK FOR SPREADABLE FIRES MAINLY FOR DRY FUELS LIKE GRASS AND TREE LITTER AND PARTICULARLY FOR SOUTH CENTRAL LOWER MI WHICH HAS BEEN DRYER THAN OTHER AREAS. PLEASE SEE THE FIRE WEATHER DISCUSSION FOR SPECIFICS. SECONDLY...THURSDAY LOOKS TO BE A SHOWERY DAY WITH A LOW RISK FOR A THUNDERSTORM. OVERALL...MODELS ARE ZONING IN ON A SHOWERY SETUP FOR THURSDAY ACROSS MUCH OF THE CWA NOW WITH A WING OF WARM AIR ADVECTION MOVING IN ALBEIT WITH WEAK FORCING AT THE SFC AND ALOFT. GFS AND ECMWF ARE SHOWING AT LEAST SOME SFC CONVERGENCE ALONG/EAST OF A LINE FROM SOUTH HAVEN TO GRR TO MT. PLEASANT DURING THE DAY. THIS IS WHERE MODEL QPF IS HIGHEST. INCREASED POPS A BIT FOR THIS EVENT ACROSS MUCH OF THE CWA GIVEN MODELS LOCKING IN ON THIS SCENARIO NOW. THE RISK FOR THUNDER STILL LOOKS LOW TO ME AND I CONSIDERED REMOVING MENTION OF IT ALTOGETHER...BASED ON NO CAPE TO BE FOUND ON ANY MODEL SOUNDINGS. NEVERTHELESS...GIVEN THE TIMING OF THIS SYSTEM I SUPPOSE IT IS POSSIBLE TO GET A RUMBLE OF THUNDER IN THE AFTERNOON AND EVENING. WITH THE CLOUDS AND SHOWERS THURSDAY WILL NOT BE AS WARM...HIGHS IN THE UPPER 50S TO LOW 60S. EASTERLY WINDS TODAY ARE ALREADY UNDERWAY. USED THE HRRR THROUGH EARLY AFTERNOON FOR THE WINDS AND THEN A BLEND OF THE HI-RES WRF ARW AND A SEPARATE MEDIUM RANGE MODEL BLEND FOR THE REST OF THE SHORT TERM. LOOKS LIKE WINDS COULD STILL GUST IN THE 20-25 MPH RANGE AT TIMES TODAY. FRIDAY LOOKS REALLY NICE. BUMPED HIGHS UP FOR MOST LOCATIONS TO 70. A LIGHT SOUTHWESTERLY WIND DURING THE AFTERNOON SHOULD KEEP LAKESHORE AREAS FROM HOLLAND TO THE NORTH SEVERAL DEGREES COOLER. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 316 AM EDT WED APR 15 2015 MODEL CONSISTENCY IS GOOD THROUGH THE PERIOD WITH THE MAIN UPSHOT BEING THAT RAIN MOVES IN ON SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER MICHIGAN. THE LOW BECOMES VERTICALLY STACKED NORTH OF LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER MICHIGAN ON TUESDAY. GIVEN WET BULB ZERO HEIGHTS CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE WET SNOW ACROSS AT LEAST THE NORTHERN ZONES AT TIMES ON TUESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 732 AM EDT WED APR 15 2015 VFR CONDITIONS THROUGH TONIGHT. EAST WINDS WILL PICK UP THIS MORNING WITH SOME GUSTS NEAR 20 KNOTS THEN DECREASE TO AOB 10 KNOTS BY THIS EVENING. && .MARINE... ISSUED AT 1104 AM EDT WED APR 15 2015 OFFSHORE FLOW WILL ACT TO KEEP WAVE HEIGHTS TO A MINIMUM. GUSTS OVER 20 KNOTS LIKELY. WINDS WILL DECREASE SOMEWHAT TONIGHT AS WE LOSE THE MIXING. WINDS WILL THEN LARGELY REMAIN UNDER 20 KNOTS THROUGH THURSDAY NIGHT. && .FIRE WEATHER... ISSUED AT 316 AM EDT WED APR 15 2015 BREEZY EASTERLY WINDS 10-15 MPH GUSTING UP TO 25...ALONG WITH HIGHS IN THE MID TO UPPER 60S AND MIN RH READINGS AROUND 20% OR EVEN LOWER IN PLACES WILL LEAD TO ELEVATED FIRE DANGER MAINLY FOR ESPECIALLY SOUTH CENTRAL LOWER MICHIGAN. THIS REGION HAS NOT RECEIVED AS MUCH RAIN LATELY SO THE DRY FUELS LIKE GRASSES AND TREE LITTER ARE MORE PREVALENT. PERSONS WITH BURN INTERESTS NEED TO MONITOR FIRES CLOSELY TO PREVENT SPREADING GIVEN THE VERY DRY CONDITIONS EXPECTED TODAY WITH BREEZES PICKING UP LATE THIS MORNING AND AFTERNOON. && .HYDROLOGY... ISSUED AT 245 PM EDT TUE APR 14 2015 DRY WEATHER THROUGH TODAY... THEN A CHANCE OF RAIN ON THURSDAY. EXPECTED PRECIPITATION AMOUNTS ARE VERY LOW IN THE MAPLE RIVER BASIN AND ZERO IN THE OTHER TWO BASINS CURRENTLY UNDER THE ADVISORY. THIS WILL ALLOW THOSE RIVERS TO FALL BELOW BANKFULL OVER THE NEXT DAY OR TWO. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...HOVING SHORT TERM...HOVING LONG TERM...OSTUNO AVIATION...OSTUNO FIRE WEATHER...HOVING HYDROLOGY...CAS MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
732 AM EDT WED APR 15 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 316 AM EDT WED APR 15 2015 DRY AND BREEZY CONDITIONS TODAY MAY INCREASE FIRE DANGER ACROSS PORTIONS OF SOUTHERN LOWER MICHIGAN. AFTER SHOWERS ON THURSDAY...A WARM AND DRY STRETCH FOR FRIDAY AND SATURDAY LOOKS LIKELY. SOME RAIN RETURNS FOR LATER SUNDAY. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 316 AM EDT WED APR 15 2015 TWO MAIN ISSUES TO ADDRESS IN THE SHORT TERM. FIRST...BREEZY CONDITIONS TODAY WILL INCREASE A RISK FOR SPREADABLE FIRES MAINLY FOR DRY FUELS LIKE GRASS AND TREE LITTER AND PARTICULARLY FOR SOUTH CENTRAL LOWER MI WHICH HAS BEEN DRYER THAN OTHER AREAS. PLEASE SEE THE FIRE WEATHER DISCUSSION FOR SPECIFICS. SECONDLY...THURSDAY LOOKS TO BE A SHOWERY DAY WITH A LOW RISK FOR A THUNDERSTORM. OVERALL...MODELS ARE ZONING IN ON A SHOWERY SETUP FOR THURSDAY ACROSS MUCH OF THE CWA NOW WITH A WING OF WARM AIR ADVECTION MOVING IN ALBEIT WITH WEAK FORCING AT THE SFC AND ALOFT. GFS AND ECMWF ARE SHOWING AT LEAST SOME SFC CONVERGENCE ALONG/EAST OF A LINE FROM SOUTH HAVEN TO GRR TO MT. PLEASANT DURING THE DAY. THIS IS WHERE MODEL QPF IS HIGHEST. INCREASED POPS A BIT FOR THIS EVENT ACROSS MUCH OF THE CWA GIVEN MODELS LOCKING IN ON THIS SCENARIO NOW. THE RISK FOR THUNDER STILL LOOKS LOW TO ME AND I CONSIDERED REMOVING MENTION OF IT ALTOGETHER...BASED ON NO CAPE TO BE FOUND ON ANY MODEL SOUNDINGS. NEVERTHELESS...GIVEN THE TIMING OF THIS SYSTEM I SUPPOSE IT IS POSSIBLE TO GET A RUMBLE OF THUNDER IN THE AFTERNOON AND EVENING. WITH THE CLOUDS AND SHOWERS THURSDAY WILL NOT BE AS WARM...HIGHS IN THE UPPER 50S TO LOW 60S. EASTERLY WINDS TODAY ARE ALREADY UNDERWAY. USED THE HRRR THROUGH EARLY AFTERNOON FOR THE WINDS AND THEN A BLEND OF THE HI-RES WRF ARW AND A SEPARATE MEDIUM RANGE MODEL BLEND FOR THE REST OF THE SHORT TERM. LOOKS LIKE WINDS COULD STILL GUST IN THE 20-25 MPH RANGE AT TIMES TODAY. FRIDAY LOOKS REALLY NICE. BUMPED HIGHS UP FOR MOST LOCATIONS TO 70. A LIGHT SOUTHWESTERLY WIND DURING THE AFTERNOON SHOULD KEEP LAKESHORE AREAS FROM HOLLAND TO THE NORTH SEVERAL DEGREES COOLER. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 316 AM EDT WED APR 15 2015 MODEL CONSISTENCY IS GOOD THROUGH THE PERIOD WITH THE MAIN UPSHOT BEING THAT RAIN MOVES IN ON SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER MICHIGAN. THE LOW BECOMES VERTICALLY STACKED NORTH OF LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER MICHIGAN ON TUESDAY. GIVEN WET BULB ZERO HEIGHTS CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE WET SNOW ACROSS AT LEAST THE NORTHERN ZONES AT TIMES ON TUESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 732 AM EDT WED APR 15 2015 VFR CONDITIONS THROUGH TONIGHT. EAST WINDS WILL PICK UP THIS MORNING WITH SOME GUSTS NEAR 20 KNOTS THEN DECREASE TO AOB 10 KNOTS BY THIS EVENING. && .MARINE... ISSUED AT 325 AM EDT WED APR 15 2015 NO SIGNIFICANT IMPACTS TO MARINERS OUTSIDE OF A LOW RISK FOR A THUNDERSTORM THURSDAY. && .FIRE WEATHER... ISSUED AT 316 AM EDT WED APR 15 2015 BREEZY EASTERLY WINDS 10-15 MPH GUSTING UP TO 25...ALONG WITH HIGHS IN THE MID TO UPPER 60S AND MIN RH READINGS AROUND 20% OR EVEN LOWER IN PLACES WILL LEAD TO ELEVATED FIRE DANGER MAINLY FOR ESPECIALLY SOUTH CENTRAL LOWER MICHIGAN. THIS REGION HAS NOT RECEIVED AS MUCH RAIN LATELY SO THE DRY FUELS LIKE GRASSES AND TREE LITTER ARE MORE PREVALENT. PERSONS WITH BURN INTERESTS NEED TO MONITOR FIRES CLOSELY TO PREVENT SPREADING GIVEN THE VERY DRY CONDITIONS EXPECTED TODAY WITH BREEZES PICKING UP LATE THIS MORNING AND AFTERNOON. && .HYDROLOGY... ISSUED AT 245 PM EDT TUE APR 14 2015 DRY WEATHER THROUGH TODAY... THEN A CHANCE OF RAIN ON THURSDAY. EXPECTED PRECIPITATION AMOUNTS ARE VERY LOW IN THE MAPLE RIVER BASIN AND ZERO IN THE OTHER TWO BASINS CURRENTLY UNDER THE ADVISORY. THIS WILL ALLOW THOSE RIVERS TO FALL BELOW BANKFULL OVER THE NEXT DAY OR TWO. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...HOVING SHORT TERM...HOVING LONG TERM...OSTUNO AVIATION...OSTUNO FIRE WEATHER...HOVING HYDROLOGY...CAS MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
328 AM EDT WED APR 15 2015 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM/FIRE WEATHER .SYNOPSIS... ISSUED AT 316 AM EDT WED APR 15 2015 DRY AND BREEZY CONDITIONS TODAY MAY INCREASE FIRE DANGER ACROSS PORTIONS OF SOUTHERN LOWER MICHIGAN. AFTER SHOWERS ON THURSDAY...A WARM AND DRY STRETCH FOR FRIDAY AND SATURDAY LOOKS LIKELY. SOME RAIN RETURNS FOR LATER SUNDAY. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 316 AM EDT WED APR 15 2015 TWO MAIN ISSUES TO ADDRESS IN THE SHORT TERM. FIRST...BREEZY CONDITIONS TODAY WILL INCREASE A RISK FOR SPREADABLE FIRES MAINLY FOR DRY FUELS LIKE GRASS AND TREE LITTER AND PARTICULARLY FOR SOUTH CENTRAL LOWER MI WHICH HAS BEEN DRYER THAN OTHER AREAS. PLEASE SEE THE FIRE WEATHER DISCUSSION FOR SPECIFICS. SECONDLY...THURSDAY LOOKS TO BE A SHOWERY DAY WITH A LOW RISK FOR A THUNDERSTORM. OVERALL...MODELS ARE ZONING IN ON A SHOWERY SETUP FOR THURSDAY ACROSS MUCH OF THE CWA NOW WITH A WING OF WARM AIR ADVECTION MOVING IN ALBEIT WITH WEAK FORCING AT THE SFC AND ALOFT. GFS AND ECMWF ARE SHOWING AT LEAST SOME SFC CONVERGENCE ALONG/EAST OF A LINE FROM SOUTH HAVEN TO GRR TO MT. PLEASANT DURING THE DAY. THIS IS WHERE MODEL QPF IS HIGHEST. INCREASED POPS A BIT FOR THIS EVENT ACROSS MUCH OF THE CWA GIVEN MODELS LOCKING IN ON THIS SCENARIO NOW. THE RISK FOR THUNDER STILL LOOKS LOW TO ME AND I CONSIDERED REMOVING MENTION OF IT ALTOGETHER...BASED ON NO CAPE TO BE FOUND ON ANY MODEL SOUNDINGS. NEVERTHELESS...GIVEN THE TIMING OF THIS SYSTEM I SUPPOSE IT IS POSSIBLE TO GET A RUMBLE OF THUNDER IN THE AFTERNOON AND EVENING. WITH THE CLOUDS AND SHOWERS THURSDAY WILL NOT BE AS WARM...HIGHS IN THE UPPER 50S TO LOW 60S. EASTERLY WINDS TODAY ARE ALREADY UNDERWAY. USED THE HRRR THROUGH EARLY AFTERNOON FOR THE WINDS AND THEN A BLEND OF THE HI-RES WRF ARW AND A SEPARATE MEDIUM RANGE MODEL BLEND FOR THE REST OF THE SHORT TERM. LOOKS LIKE WINDS COULD STILL GUST IN THE 20-25 MPH RANGE AT TIMES TODAY. FRIDAY LOOKS REALLY NICE. BUMPED HIGHS UP FOR MOST LOCATIONS TO 70. A LIGHT SOUTHWESTERLY WIND DURING THE AFTERNOON SHOULD KEEP LAKESHORE AREAS FROM HOLLAND TO THE NORTH SEVERAL DEGREES COOLER. && .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 316 AM EDT WED APR 15 2015 MODEL CONSISTENCY IS GOOD THROUGH THE PERIOD WITH THE MAIN UPSHOT BEING THAT RAIN MOVES IN ON SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER MICHIGAN. THE LOW BECOMES VERTICALLY STACKED NORTH OF LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER MICHIGAN ON TUESDAY. GIVEN WET BULB ZERO HEIGHTS CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE WET SNOW ACROSS AT LEAST THE NORTHERN ZONES AT TIMES ON TUESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1155 PM EDT TUE APR 14 2015 EAST WINDS WILL BE ON THE INCREASE... WITH SPEEDS OF 10 TO 20 KTS EXPECTED WEDNESDAY INTO WEDNESDAY EVENING. ONLY HIGH LEVEL CLOUDINESS WILL BE PRESENT OVER THE NEXT 24 HOURS... WITH BASES ABOVE 12,000 FT. RAIN SHOWERS ARE EXPECTED TO HOLD OFF UNTIL AFTER 06Z THURSDAY WITH THE THREAT OF LOWER MVFR OR IFR CIGS LIKELY HOLDING OFF UNTIL AFTER 12Z THURSDAY. && .MARINE... ISSUED AT 325 AM EDT WED APR 15 2015 NO SIGNIFICANT IMPACTS TO MARINERS OUTSIDE OF A LOW RISK FOR A THUNDERSTORM THURSDAY. && .FIRE WEATHER... ISSUED AT 316 AM EDT WED APR 15 2015 BREEZY EASTERLY WINDS 10-15 MPH GUSTING UP TO 25...ALONG WITH HIGHS IN THE MID TO UPPER 60S AND MIN RH READINGS AROUND 20% OR EVEN LOWER IN PLACES WILL LEAD TO ELEVATED FIRE DANGER MAINLY FOR ESPECIALLY SOUTH CENTRAL LOWER MICHIGAN. THIS REGION HAS NOT RECEIVED AS MUCH RAIN LATELY SO THE DRY FUELS LIKE GRASSES AND TREE LITTER ARE MORE PREVALENT. PERSONS WITH BURN INTERESTS NEED TO MONITOR FIRES CLOSELY TO PREVENT SPREADING GIVEN THE VERY DRY CONDITIONS EXPECTED TODAY WITH BREEZES PICKING UP LATE THIS MORNING AND AFTERNOON. && .HYDROLOGY... ISSUED AT 245 PM EDT TUE APR 14 2015 DRY WEATHER THROUGH TODAY... THEN A CHANCE OF RAIN ON THURSDAY. EXPECTED PRECIPITATION AMOUNTS ARE VERY LOW IN THE MAPLE RIVER BASIN AND ZERO IN THE OTHER TWO BASINS CURRENTLY UNDER THE ADVISORY. THIS WILL ALLOW THOSE RIVERS TO FALL BELOW BANKFULL OVER THE NEXT DAY OR TWO. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...HOVING SHORT TERM...HOVING LONG TERM...OSTUNO AVIATION...MEADE FIRE WEATHER...HOVING HYDROLOGY...CAS MARINE...MJS
AREA FORECAST DISCUSSION
NWS DULUTH MN
352 AM CDT WED APR 15 2015 .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 347 AM CDT WED APR 15 2015 SHORT TERM FOCUS ON LOW RH AND GUSTY SOUTH WINDS TODAY...PROMOTING CRITICAL FIRE WEATHER CONDITIONS. HAVE UPGRADED THE FIRE WEATHER WATCH TO A RED FLAG WARNING FOR ALL OF NE MINNESOTA...AND A PORTION OF NW WISCONSIN. PLEASE REFER TO LATEST FIRE WEATHER FORECAST FOR MORE DETAILS. THE WESTERN LAKE SUPERIOR REGION WILL BE SITUATED IN A WARM SOUTHERLY FLOW AHEAD OF A SHORT WAVE/SFC REFLECTION LOW...CURRENTLY PUSHING INTO THE WESTERN DAKOTAS. LATEST NAM BUFR SOUNDINGS DEPICT STEEP LAPSE RATES WITH MIXING HTS AROUND 6000 FT THIS AFTERNOON AS SFC TEMPERATURES WARM INTO THE MIDDLE 60S TO AROUND 70F. THE VERY DRY AIR ALOFT...WITH DEW PTS IN THE TEENS...WILL BE CAPABLE OF MIXING TO THE SFC THIS AFTERNOON...RESULTING IN MINIMUM RH VALUES IN THE 15 TO 20 PERCENT RANGE. IN ADDITION...SOUTHERLY GUSTS OF 20 TO 25 KT WILL BE COMMON THROUGH THE AFTERNOON PERIOD. NEAR LAKE SUPERIOR...EAST/NORTHEAST WINDS OF 5 TO 10 MPH WILL PREVAIL FOR LOCATIONS ADJACENT TO THE WESTERN TIP AND ALONG THE NORTH SHORE OF LAKE SUPERIOR TODAY. THE LAKE BREEZE WILL KEEP CONDITIONS COOLER ALONG THE LAKE WITH TEMPERATURES RANGING FROM THE UPPER 40S TO LOW 50S. THE SHORT WAVE SLIDES EAST ACROSS SOUTHERN MANITOBA THIS EVENING...TRACKING INTO FAR NORTHERN MINN THURSDAY. HAVE KEPT SCHC POPS THURS ALONG THE BORDERLAND/IRON RANGE FOR A STRAY SHOWER. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 347 AM CDT WED APR 15 2015 THERE WILL BE A LOW PRESSURE SYSTEM IN CENTRAL QUEBEC THURSDAY EVENING...AND ITS ASSOCIATED COLD FRONT WILL MOVE THROUGH THE NORTHLAND THURSDAY EVENING INTO EARLY FRIDAY. THE GFS/GEM/ECMWF/NAM ARE NOT INDICATING ANY SIGNIFICANT CHANCE OF PCPN WITH THIS FRONTAL PASSAGE. A SHORTWAVE WILL CUT ACROSS SOUTH CENTRAL CANADA THURSDAY NIGHT AND FRIDAY...AND MERGE WITH A WEAK LOW OVER ONTARIO FRIDAY AFTERNOON AND EVENING. THE WEAK COLD FRONT ASSOCIATED WITH THIS LOW WILL MOVE FROM NORTH TO SOUTH THROUGH THE NORTHLAND LATE FRIDAY AND EARLY SATURDAY. MOST OF THE MODELS KEEP PCPN ASSOCIATED WITH THE SHORTWAVE AND LOW NORTH AND NE OF THE FORECAST AREA FOR FRIDAY AFTERNOON AND EVENING...BUT GAVE LOW CHANCES OF RAIN OVER THE NORTHERN FORECAST AREA SIMILAR TO THE NAM12/GEM. FRIDAY LOOKS WARM AND WINDY. GUSTY W TO WNW WINDS WILL DEVELOP BY THE EARLY AFTERNOON. INCREASED THE WINDS OVER THE PREVIOUS FORECAST WITH A HEAVY USE OF THE SREF/NAM MODELS. SUSTAINED WINDS OF 10 TO 20 MPH AND GUSTS UP TO 25 MPH ARE NOW IN THE FORECAST. THE COMBINATION OF THE GUSTY WINDS AND DRY RELATIVE HUMIDITY IN THE FORECAST SHOWS SOME AREAS OF NE MINNESOTA APPROACHING CRITICAL FIRE WEATHER CONDITIONS IN THE AFTERNOON. HIGH PRESSURE WILL MOVE INTO THE NORTHLAND FRIDAY NIGHT IN THE WAKE OF THE PASSING COLD FRONT. THIS SHOULD PROVIDE A CLEAR AND COOL NIGHT. A LOW PRESSURE SYSTEM WILL MOVE ALBERTA TO NW ONTARIO FRIDAY NIGHT THROUGH SUNDAY NIGHT. IT WILL GRADUALLY DEEPEN ALONG DURING THAT PROCESS. THE GFS/GEM/ECMWF ARE SHOWING SOUTHERLY FLOW DEVELOPING OVER THE NORTHERN PLAINS AND NORTHLAND EARLY IN THE WEEKEND AND GRADUALLY DRAWING MOIST AIR INTO THE REGION. WHILE HIGH PRESSURE OVER WESTERN LAKE SUPERIOR ON SATURDAY SHOULD HELP GIVE THE NORTHLAND A WARM AND SUNNY SATURDAY...THERE WILL LIKELY BE INCREASING CLOUD COVER SATURDAY NIGHT AND SUNDAY AS THE LOW PRESSURE SYSTEM AND ITS TROUGH BOUNDARY APPROACHES THE NORTHLAND. THE GFS/GEM/ECMWF ARE INDICATING THE NORTHLAND HAS A GOOD CHANCE OF RAIN FOR THE SECOND HALF OF THE WEEKEND AS THE LOW MOVES THROUGH THE REGION. THE GFS SHOWS PRECIPITABLE WATER VALUES INCREASING TO NEARLY 1 INCH OVER THE NORTHLAND. THE GFS IS ABOUT 6 TO 12 HOURS FASTER AT MOVING THE ASSOCIATED TROUGH BOUNDARY AND PCPN THROUGH THE FORECAST AREA SATURDAY NIGHT AND SUNDAY. INCREASED THE PCPN CHANCES OVER THE PREVIOUS FORECAST...AND WE WILL LIKELY NEED TO INCREASE MUCH HIGHER ONCE THE MODELS COME INTO BETTER AGREEMENT ON THE TIMING OF THIS RAIN. THE LOW SHOULD BE IN NW ONTARIO BY EARLY MONDAY. THE GFS/ECMWF ARE SHOWING ANOTHER LOW IN THE MIDWEST LIFTING AND MERGING WITH THE ONTARIO LOW SOMEWHERE OVER THE NORTHERN GREAT LAKES REGION BY LATE MONDAY. THIS COULD CREATE AN EVEN LARGER AND DEEPER LOW OVER THE GREAT LAKES REGION AND WHICH COULD WOBBLE AROUND LAKE SUPERIOR AND ONTARIO THROUGH THE MIDDLE OF THIS WEEK. IF THIS SCENARIO HAPPENS...AS THE GFS AND ECMWF SUGGEST...THEN THE NORTHLAND COULD SEE A COUPLE DAYS OF COOL NW FLOW...BKN/OVC CLOUD COVER...AND LOW CHANCES OF RAIN AND LIGHT SNOW SHOWERS MONDAY THROUGH WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1257 AM CDT WED APR 15 2015 VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGHOUT THE PERIOD. LAST SEVERAL RAP RUNS SHOW A STRONG LOW LEVEL JET DEVELOPING EARLY THIS MORNING IN MINNESOTA...SO ADDED LOW LEVEL WIND SHEAR TO ALL NE MINNESOTA TERMINALS BETWEEN 06Z AND 14Z. HIGH PRESSURE WILL BUILD INTO WESTERN QUEBEC TODAY...WHILE A LOW MOVES INTO NE MANITOBA. THIS SETUP WILL RESULT IN A TIGHT PRESSURE GRADIENT ACROSS ALL TAF SITES BY 16Z TO 17Z. THIS IN COMBINATION WITH DAY TIME HEATING WILL ALLOW FOR GUSTY SOUTHERLY SFC WINDS. WINDS WILL DIMINISH AFTER SUNSET. && .PRELIMINARY POINT TEMPS/POPS... DLH 64 41 59 40 / 0 10 10 0 INL 70 45 59 34 / 0 20 20 0 BRD 69 44 66 39 / 0 20 10 0 HYR 67 40 65 41 / 0 10 10 0 ASX 69 40 66 40 / 0 10 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR MNZ010>012-018-019-025-026-033>038. WI...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR WIZ001-002-006>008. LS...NONE. && $$ SHORT TERM...GRANING LONG TERM...GROCHOCINSKI AVIATION...GROCHOCINSKI/WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
1258 AM CDT WED APR 15 2015 .UPDATE... ISSUED AT 522 PM CDT TUE APR 14 2015 UPDATED FOR HEADLINE INFORMATION AT THE BOTTOM...TO ADD FIRE WEATHER WATCH FOR FAR NORTHWESTERN WISCONSIN. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY AFTERNOON) ISSUED AT 325 PM CDT TUE APR 14 2015 WEATHER CONDITIONS IN THE SHORT TERM REMAIN FAIRLY QUIET WITH HIGH PRESSURE DOMINATING MUCH OF THE REGION UNDER MOSTLY CLEAR SKIES AND ABOVE AVERAGE TEMPERATURES. AN AMPLIFYING RIDGE OF HIGH PRESSURE OVER THE UPPER MIDWEST WILL CONTINUE TO BUILD OVER THE REGION TONIGHT AND TOMORROW AS THE NEXT LOW PRESSURE SYSTEM SLIDES FROM THE NRN ROCKIES INTO THE DAKOTAS. AHEAD OF THIS SYSTEM A STRENGTHENING PRESSURE GRADIENT OVER THE ERN DAKOTAS AND WRN MN WILL USHER IN A WARM AIR MASS ACROSS THE REGION. WILL ALSO SEE SOUTHERLY WINDS REMAIN AROUND 5 TO 10 MPH THROUGH TONIGHT...WITH MUCH STRONGER WINDS TO THE WEST OVER THE RED RIVER VALLEY...AND A GRADUAL INCREASE IN SOUTH WINDS ACROSS PORTIONS OF THE NORTHLAND THROUGH THE LATE MORNING AND AFTERNOON. SHOULD SEE SUSTAINED SOUTH WINDS AROUND 10 TO 20 MPH WITH GUSTS 20 TO 30 MPH ON WED. EXPECT TO SEE HIGH LEVEL THIN CLOUDS STREAMING IN FROM THE SOUTH WED MORNING WITH AN INCREASE IN CLOUD THICKNESS IN THE MID TO LATE AFTERNOON. TEMPERATURES WILL WARM THROUGH THE DAY UNDER MOSTLY SUNNY SKIES IN THE MORNING AND EARLY AFTERNOON. HIGHS ARE EXPECTED TO TOP OUT IN THE MID TO UPPER 60S...WITH THE EXCEPTION OF AROUND THE IMMEDIATE LAKE SHORE FROM THE TWIN PORTS AND ALONG THE NORTH SHORE WHERE A WEAK LAKE BREEZE WILL KEEP CONDITIONS NOTICEABLY COOLER...IN THE UPPER 40S AND 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 325 PM CDT TUE APR 14 2015 UPPER LEVEL/SFC RIDGING PREVAIL OVER THE FORECAST AREA ON WEDNESDAY EVENING SUPPORTING NO PCPN. MODEL DIFFERENCES SHOW UP AFTER 06Z THURSDAY. GFS/NAM BRING IN QPF WHILE ECMWF DRIER AND GEM HAS NO QPF. USED A MODEL BLEND WHICH GAVE SMALL POPS TO THE WESTERN EDGE OF THE AREA IN RESPONSE TO A SHORT WAVE TROF MOVING ACROSS THE REGION. THIS MAY CHANGE IN FUTURE RUNS AS DRY HIGH PRESSURE REMAINS NEARBY WHICH IS KEEPING DRIER AIR FROM BEING OVERCOME BY MOISTURE. MAINTAINED THE PREVIOUS FORECAST OF POPS ON THURSDAY MORNING AS THE SHORT WAVE DEPARTS. HIGH PRESSURE PREVAILS THURSDAY AFTERNOON. MODELS STILL TRYING TO GENERATE SOME SHOWERS THURSDAY NIGHT AHEAD OF NEXT SHORT WAVE REACHING THE NORTHERN PLAINS. WILL KEEP THURSDAY NIGHT PCPN FREE AS DRIER AIR LOCKED IN WILL BE TOUGH TO OVERCOME. MAJOR DIFFERENCES IN THE MODELS FOR FRIDAY WITH THE GFS WET...ECMWF DRY AND NAM/GEM IN BETWEEN. MAINTAINED THE BLENDED APPROACH WHICH RESULTED IN VERY LITTLE CHANGE FROM WHAT WAS ALREADY IN THE FORECAST. DIALED DOWN THE QPF WITH SUCH LARGE DISCREPANCIES. THESE DIFFERENCES PERSIST AND CONTINUED WITH THE BLENDED APPROACH WITH POPS OVER THE ARROWHEAD AND IRON COUNTY WI AS THE UPPER TROF MOVES AWAY. HIGH PRESSURE BUILDS OVER THE REST OF THE REGION. HIGH PRESSURE COVERS THE AREA SATURDAY. MODELS REMAIN IN DISAGREEMENT SATURDAY NIGHT THROUGH MONDAY AND USED A CONSENSUS FOR POPS/QPF. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1257 AM CDT WED APR 15 2015 VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGHOUT THE PERIOD. LAST SEVERAL RAP RUNS SHOW A STRONG LOW LEVEL JET DEVELOPING EARLY THIS MORNING IN MINNESOTA...SO ADDED LOW LEVEL WIND SHEAR TO ALL NE MINNESOTA TERMINALS BETWEEN 06Z AND 14Z. HIGH PRESSURE WILL BUILD INTO WESTERN QUEBEC TODAY...WHILE A LOW MOVES INTO NE MANITOBA. THIS SETUP WILL RESULT IN A TIGHT PRESSURE GRADIENT ACROSS ALL TAF SITES BY 16Z TO 17Z. THIS IN COMBINATION WITH DAY TIME HEATING WILL ALLOW FOR GUSTY SOUTHERLY SFC WINDS. WINDS WILL DIMINISH AFTER SUNSET. && .PRELIMINARY POINT TEMPS/POPS... DLH 43 62 42 64 / 10 10 10 20 INL 47 62 36 63 / 10 20 0 20 BRD 46 66 42 66 / 20 10 0 10 HYR 42 66 43 66 / 10 10 0 20 ASX 42 64 42 65 / 10 10 0 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...FIRE WEATHER WATCH FROM NOON CDT TODAY THROUGH THIS EVENING FOR MNZ010>012-018-019-025-026-033>038. WI...FIRE WEATHER WATCH FROM NOON CDT TODAY THROUGH THIS EVENING FOR WIZ001-002-006-007. LS...NONE. && $$ UPDATE...DAP SHORT TERM...BJT LONG TERM...GSF AVIATION...GROCHOCINSKI/WL
AREA FORECAST DISCUSSION
NWS JACKSON MS
1015 PM CDT THU APR 16 2015 .UPDATE... HAVE MADE MINOR ADJUSTMENTS MADE TO REDUCE OVERNIGHT POPS AND THUNDER POTENTIAL. LATEST HRRR GUIDANCE SUGGESTS THAT ADDITONAL CONVECTIVE RAINFALL DEVELOPING OVER WRN/SRN LA ASSOCIATED WITH A WEAK MID LEVEL SHORTWAVE TROUGH WILL DEVELOP SLOWLY EAST OVERNIGHT...BUT THE AIRMASS IS SOMEWHAT STABILIZED FROM EARLIER CONVECTION. ALL ELSE IS GENERALLY ON TRACK. && .PREV DISCUSSION... /ISSUED 310 PM CDT THU APR 16 2015/ SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT...COUPLED UPPER LEVEL JET CURRENTLY ALLOWING THE DEVEOLPMENT OF WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY FROM SOUTHEAST TEXAS INTO MISSISSIPPI. EXPECT STORMS TO CONTINUE TO INCREASE IN COVERAGE AND INTENSITY LATE THIS AFTERNOON AND EVENING. HEAVY RAINFALL WILL BE A CONCERN AND A SEVERE STORM IS ALSO POSSIBLE. BOTH HAZARDS MAY BE ENHANCED BY WHAT APPEARS TO BE AN MCV DEVELOPING OVER SOUTHWEST MISSISSIPPI AND A BOUNDARY EXTENDING FROM NORTHEAST LOUISIANA TO AROUND OXFORD. THIS ACTIVITY WILL CONTINUE WELL INTO THE EVENING HOURS AS THE JETS AND MOISTURE REMAIN IN PLACE. LATER TONIGHT AND INTO FRIDAY...WILL HAVE TO WATCH THE ACTIVITY FURTHER WEST ACROSS TEXAS. STORMS MAY SURVIVE AND MOVE INTO OUR AREA OR MCVS MAY SURVIVE AND CAUSE REFORMATION OF STORMS IN THE VERY MOIST AND UNSTABLE ENVIRONMENT. MODELS PROG A MORE SUBSTANTIAL WAVE TO MOVE ACROSS THE AREA ON SATURDAY. HIGH PRECIPITABLE WATER VALUES AND MODERATE INSTABILITY WILL AGAIN LEAD TO SEVERE WEATHER AND HEAVY RAINFALL POTENTIAL PRIMARILY OVER SOUTHERN PORTIONS OF THE FORECAST AREA. /SW/ SUNDAY INTO SUNDAY NIGHT...AFTER A ACTIVE CONVECTIVE PERIOD...THE ATMOSPHERE WILL QUICKLY RECOVER AND SETUP A TOTALLY DIFFERENT THERMODYNAMIC PROFILE FOR SUNDAY. AS DEEP MOISTURE EXITS EAST BY EARLY SUNDAY...COLDER TEMPS ALOFT (-15C) WILL SPREAD EAST. THIS WILL COMBINE WITH WARMING LOW LEVELS TO SUPPORT A VERY STEEP LAPSE RATE ENVIRONMENT. VERTICAL TOTALS OF 29-30C WILL EXIST ALONG WITH H7-H5 LAPSE RATES AROUND 7.5 C/KM. THIS WILL SUPPORT SBCAPE VALUES OF 2500-3000 J/KG. OVERALL...THE ATMOSPHERIC COLUMN WILL BE A BIT DRY (PW`S 1.2 INCH) WITH A WEAK CAP IN PLACE. THE OVERALL FLOW ALOFT WILL NOT BE OVERLY FAST BUT CYCLONIC AND CONTAINING A FEW SPOKES OF ENERGY AND LIFT. GUIDANCE FROM THE EURO/GFS/CANADIAN ARE ALL IN SOLID AGREEMENT ON THIS SETUP AND EACH INDICATE SOME CONVECTIVE DEVELOPMENT THROUGH AN EXTENDED WINDOW FROM AT LEAST MIDDAY INTO LATE EVENING. DUE TO THE CAP AND GENERAL DRYNESS OF THE ATMOSPHERE...EXPECTATIONS ARE FOR MORE ISO/SCT TYPE STORMS AND OF SUPERCELL MODE. THE VOLATILE SETUP OF THE ENVIRONMENT WILL SUPPORT ROBUST UPDRAFTS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. AT THIS TIME...ENOUGH UNCERTAINTY EXISTS IN EVOLUTION TO NOT GET TOO AGGRESSIVE WITH THE OUTLOOK. HOWEVER...MULTIPLE INGREDIENTS ARE IN PLACE FOR AT LEAST GOLF BALL SIZED HAIL AND DAMAGING WINDS. THE POTENTIAL OF TORNADOES IS NON- ZERO...BUT APPEARS TO LOW AT THIS TIME TO INCLUDE IN THE OUTLOOK. DUE TO THIS...WILL INTRODUCE AN OUTLOOK FOR SUNDAY WITH HIGHER CONFIDENCE ACROSS THE NORTHERN 2/3RDS TO RECEIVED SVR STORMS. AN UPDATE TO THE OUTLOOK MAY BE WARRANTED IF CONFIDENCE INCREASES IN THE POTENTIAL FOR LARGER HAIL. /CME/ LONG TERM...MONDAY THROUGH THURSDAY...DRIER AIR WILL FILTER INTO THE REGION EARLY NEXT WEEK AS HIGH PRESSURE BUILDS INTO THE CWA FROM THE NORTHWEST. THIS CURRENTLY LOOKS TO LEAD TO A DRY PERIOD FOR MONDAY AND TUESDAY. RAIN CHANCES COULD CREEP BACK INTO THE FORECAST FOR THE MIDDLE OF THE WORK WEEK AS WARM ADVECTION ENSUES AT THE SURFACE. ALOFT... WHILE OUR FLOW ALOFT BECOMES MORE ZONAL...A SERIES OF UPPER LEVEL DISTURBANCES SHIFTING EAST THROUGH THE REGION COULD CAUSE SOME RAIN TO DEVELOP ACROSS FORECAST AREA. /19/SW/ && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1045 AM CDT WED APR 15 2015 .UPDATE...SKIES WERE MOSTLY CLOUDY LATE THIS AM ACROSS MUCH OF THE ARKLAMISS WITH TEMPERATURES MAINLY AROUND 70...WITH HIGHS THIS AFTERNOON EXPECTED TO BE AROUND 80. LATEST HRRR INDICATES BEST COVERAGE OF SHWR/TSTM ACTIVITY LATER THIS AFTERNOON ACROSS THE E/SE...WHICH IS ON TRACK WITH THE CURRENT FCST. THE ONLY CHANGE TO THE CURRENT FCST WAS TO THE HOURLY TEMPS TO ACCOUNT FOR THE LATEST TENDS. /27/ && .AVIATION...VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THIS AFTERNOON AND EVENING. DEEPER MIXING THIS AFTERNOON WILL ALLOW WIND SPEEDS TO CREEP UP SOMEWHAT HIGHER THAN THE PAST FEW DAYS. SPEEDS OF 5 TO 15 KNOTS WILL BE COMMON...ESPECIALLY AROUND GLH/GWO. SOME TSRA WILL BE POSSIBLE TODAY...BUT NO MORE THAN VICINITY EXPECTED. HBG WILL HAVE THE BEST CHANCE AT SEEING SOME TSRA THIS AFTERNOON. MVFR/IFR CEILINGS WILL OVERSPREAD THE AREA ONCE AGAIN AFTER 16/06Z. VSBYS WILL MOSTLY STAY IN THE MVFR CATEGORY...BUT LIFR VSBYS IN FOG ARE MORE PROBABLE OVER HBG HEADING TOWARD 16/12Z./26/ && .PREV DISCUSSION... /ISSUED 421 AM CDT WED APR 15 2015/ SHORT TERM...TODAY THROUGH THURSDAY NIGHT...EVENING SHOWERS HAVE MOVED NORTH OF THE REGION AND ONCE AGAIN A LULL IN THE RAIN ACTIVITY IS ONGOING OVERNIGHT. A STALLED FRONT IS DRAPED ACROSS THE REGION GENERALLY NEAR THE HIGHWAY 82 CORRIDOR. ANOTHER DAY OF SHOWERS AND SOME STORMS WILL BE POSSIBLE BUT IT APPEARS THAT CONVECTION WILL TAKE A LITTLE LONGER TO GET GOING AND CONFIDENCE IS NOT HIGH IN HOW MUCH COVERAGE THERE WILL BE. UNLIKE THE PREVIOUS FEW MORNINGS...CONVECTION IS NOT NOTED ON RADAR MOVING IN FROM THE SOUTHWEST. GLOBAL MODELS INDICATE THAT QPF LIKELY WONT OCCUR UNTIL CLOSER TO THE AFTERNOON AND EVEN THE HI-RES MODELS ARE VERY SPARSE WITH THE RAIN THROUGH THE WHOLE DAY...WITH MORE OCCURRING IN THE AFTERNOON. THIS IS LIKELY DUE TO THE LATER ARRIVAL OF THE WEAK DISTURBANCE/LOW PRESSURE MOVING GENERALLY ALONG THE STALLED FRONT TO THE NORTHEAST. I DIDNT GO AS HIGH WITH POPS AS PREVIOUS DAYS GIVEN SOME INDICATION PER HI-RES GUIDANCE THAT COVERAGE MAY NOT BE AS GREAT TODAY. THAT AND SOME DRIER AIR APPEARS TO BE IN PLACE THIS MORNING. THIS IS NOTED BY LOWER 60S DEWPOINTS...DRIER AIR MOVING INTO THE REGION FROM ARKANSAS AND LOUISIANA PER WATER VAPOR IMAGERY...AND MODEL PROGGED PW VALUES LESS THAN 1.5 INCHES. IT APPEARS THAT THE BETTER CHANCE FOR RAIN/STORMS WILL BE IN THE EAST LATER THIS AFTERNOON AND SOME OF THESE STORMS COULD GET ON THE STRONG TO MAYBE MARGINALLY SEVERE SIDE. LATER IN THE DAY...AS MID LEVEL TEMPERATURES CONTINUE TO COOL...VERTICAL TOTALS ARE FORECAST TO BE AROUND 26-28C. WHILE WIND SHEAR ISNT TOO STRONG...IT COULD BE SUFFICIENT ENOUGH(DEEP LAYER SHEAR AROUND 30KTS) TO PRODUCE A FEW STRONG STORMS WITH GUSTY WINDS AND PERHAPS SOME HAIL BEING THE MAIN CONCERNS. I STILL HAVE A GOOD BIT OF UNCERTAINTY AS TO HOW MUCH CONVECTION WILL OCCUR GIVEN INTRUDING DRIER AIR AND THUS WILL HOLD OFF FOR NOW IN MENTIONING ANY OF THIS IN THE HWO/GRAPHICS. AS HAS BEEN THE CASE ALL WEEK...LOCALLY HEAVY RAIN COULD BRING POTENTIAL FOR LOCALIZED FLASH FLOODING WITH ANY STORMS THAT DEVELOP. WILL KEEP LIMITED POTENTIAL IN THE HWO FOR TODAY. AS THE SFC LOW TRACKS THE NORTHEAST...RAIN SHOULD MOVE OFF TO THE NORTHEAST AS WELL BY MIDNIGHT BUT SOME SMALL CHANCES FOR SHOWERS WILL EXIST OVERNIGHT TONIGHT. MOISTURE WILL BE A BIT HIGHER ON THURSDAY AS PW VALUES RETURN TO NEAR 1.8 INCHES. THIS...ALONG WITH DAYTIME HEATING AND WEAK DISTURBANCES...WILL BRING BETTER COVERAGE OF SHOWERS AND STORMS TO THE REGION ESPECIALLY FOR SOUTHERN PORTIONS OF MY CWA. /28/ LONG TERM...FRIDAY THROUGH WEDNESDAY...THE UNSETTLED WET PATTERN WITH THE ACTIVE SOUTHERN JETSTREAM WILL CONTINUE THROUGH SATURDAY. THE UPPER JET WILL CONTINUE TO AID IN PROVIDING PERIODS OF LIFT AS A SERIES OF DISTURBANCES TRACK THROUGH THE SOUTHERN STREAM. MODELS CONTINUE TO HAVE ISSUES WITH TRACKING THE HIGHEST RAINFALL POTENTIAL AREAS WITH MESO-SCALE FEATURES INVOLVED. THUS TIMING AND DETAILS REMAIN TOUGH TO NAIL DOWN THROUGH THE UNSETTLED PERIOD. ANOMALOUS MOISTURE WILL CONTINUE UNTIL SATURDAY NIGHT. EXPECT THE POTENTIAL FOR CONVECTIVE ACTIVITY WITH LOCALLY HEAVY RAINFALL RATES...WHICH WILL BRING SOME RISK OF FLASH FLOODING. AN ADDITIONAL 1-3 INCHES APPEARS POSSIBLE FRI WITH LOCALLY HIGHER AMOUNTS POSSIBLE. A TREND THAT DOES SEEM A BIT MORE CLEAR IS THAT THE S 2/3RDS OF THE CWA HAS THE BEST POTENTIAL TO SEE THE HIGHER RAIN TOTALS. WPC HAS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS THE SOUTH ON FRIDAY. FOR THE SUN-WED PERIODS...LOOK FOR DRIER AND SLIGHTLY COOLER TO BE THE TREND AS SOME GUIDANCE PUSHES THE FRONT THROUGH THE REGION AS THE NORTHERN STREAM FINALLY PHASES./17/CE/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 80 64 80 64 / 50 36 56 58 MERIDIAN 79 64 78 64 / 52 49 56 57 VICKSBURG 80 62 81 65 / 29 27 56 58 HATTIESBURG 80 66 79 65 / 56 38 66 57 NATCHEZ 79 63 79 65 / 29 29 66 57 GREENVILLE 77 60 79 65 / 31 27 21 59 GREENWOOD 79 62 81 64 / 42 50 22 52 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1217 PM CDT Wed Apr 15 2015 ...Update to Aviation Discussion... .SHORT TERM...(Today and Tonight) Issued at 323 AM CDT WED APR 15 2015 A weak shortwave lifting ne through the region today will bring a good chance of light to occasionally moderate showers, particularly over southern MO. HRRR radar sim output looks pretty solid in terms of precip coverage and MOS guidance pops are fairly high, especially this morning. The wfo blended output is somewhat lower. Could be a rumble of thunder or two in south central MO, but mainly just rw/rw-. Significant precip should end from sw to ne late today and this evening. Some fog potential is there for tonight with residual low level moisture and a possible clearing sky late. Something for the next shift to take a closer look at. .LONG TERM...(Thursday through Tuesday) Issued at 323 AM CDT WED APR 15 2015 Global models ECMWF/GFS/GEM have tended to slow down the eastward progress just a bit with the upstream cutoff upper low expected to move into the central Rockies today. Downstream upper level ridging should limit precip chances Thursday and Thursday night (still non-zero but low) with a warming trend also expected. As the upper low shifts east precip chances will increase Friday and into the weekend. A shortwave moving southeast from western Canada is still expected to phase with and open up the southern stream cutoff and shift the upper level trough axis east of the region Monday morning. Cooler than normal temperatures are then expected Monday and Tuesday as a Canadian air mass settles in over the Midwest. && .AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 1220 PM CDT WED APR 15 2015 For the KSGF, KJLN, and KBBG TAFS: IFR conditions and an area of light rain is currently moving through the area early this afternoon. This rainfall has already pushed east of the KJLN site and will push out of the KSGF and KBBG TAF sites during the mid afternoon hours. visiblities will improve after the rain pushes out, but IFR/LIFR ceilings will continue this afternoon into early Thursday morning. Fog is expected to develop overnight into early Thursday and could become dense at times. By mid morning Thursday flight conditions should start to improve. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...DSA LONG TERM...DSA AVIATION...Wise
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
641 AM CDT Wed Apr 15 2015 .SHORT TERM...(Today and Tonight) Issued at 323 AM CDT WED APR 15 2015 A weak shortwave lifting ne through the region today will bring a good chance of light to occasionally moderate showers, particularly over southern MO. HRRR radar sim output looks pretty solid in terms of precip coverage and MOS guidance pops are fairly high, especially this morning. The wfo blended output is somewhat lower. Could be a rumble of thunder or two in south central MO, but mainly just rw/rw-. Significant precip should end from sw to ne late today and this evening. Some fog potential is there for tonight with residual low level moisture and a possible clearing sky late. Something for the next shift to take a closer look at. .LONG TERM...(Thursday through Tuesday) Issued at 323 AM CDT WED APR 15 2015 Global models ECMWF/GFS/GEM have tended to slow down the eastward progress just a bit with the upstream cutoff upper low expected to move into the central Rockies today. Downstream upper level ridging should limit precip chances Thursday and Thursday night (still non-zero but low) with a warming trend also expected. As the upper low shifts east precip chances will increase Friday and into the weekend. A shortwave moving southeast from western Canada is still expected to phase with and open up the southern stream cutoff and shift the upper level trough axis east of the region Monday morning. Cooler than normal temperatures are then expected Monday and Tuesday as a Canadian air mass settles in over the Midwest. && .AVIATION...(For the 12Z TAFS through 12Z Thursday Morning) Issued at 635 AM CDT WED APR 15 2015 Showers will move across the regions aerodromes through much of today as a shortwave moves across the region. The increased lift and moisture will allow for MVFR ceilings and visibilities through this evening, especially where showers occur. The shortwave will move east of the region for the overnight hours with lingering MVFR to IFR ceilings and visibilities though the showers will shift east along with the shortwave. Will need to monitor for fog development for early Thursday morning, especially if cloud cover clears off as projected by some of the model guidance. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...DSA LONG TERM...DSA AVIATION...Hatch
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
345 AM CDT Wed Apr 15 2015 .SHORT TERM...(Today and Tonight) Issued at 323 AM CDT WED APR 15 2015 A weak shortwave lifting ne through the region today will bring a good chance of light to occasionally moderate showers, particularly over southern MO. HRRR radar sim output looks pretty solid in terms of precip coverage and MOS guidance pops are fairly high, especially this morning. The wfo blended output is somewhat lower. Could be a rumble of thunder or two in south central MO, but mainly just rw/rw-. Significant precip should end from sw to ne late today and this evening. Some fog potential is there for tonight with residual low level moisture and a possible clearing sky late. Something for the next shift to take a closer look at. .LONG TERM...(Thursday through Tuesday) Issued at 323 AM CDT WED APR 15 2015 Global models ECMWF/GFS/GEM have tended to slow down the eastward progress just a bit with the upstream cutoff upper low expected to move into the central Rockies today. Downstream upper level ridging should limit precip chances Thursday and Thursday night (still non-zero but low) with a warming trend also expected. As the upper low shifts east precip chances will increase Friday and into the weekend. A shortwave moving southeast from western Canada is still expected to phase with and open up the southern stream cutoff and shift the upper level trough axis east of the region Monday morning. Cooler than normal temperatures are then expected Monday and Tuesday as a Canadian air mass settles in over the Midwest. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1155 PM CDT TUE APR 14 2015 An upper level disturbance will continue to bring scattered rain showers to the region through Wednesday. Occasional MVFR visibilities can be expected with heavier showers on Wednesday. Ceilings will also lower into the MVFR category late tonight with IFR then expected at Branson by early Wednesday morning. IFR potential at Springfield and Joplin is a bit lower. Ceilings may then improve for a time later Wednesday afternoon but will tend to lower again Wednesday evening. Partial clearing will also be possible starting late Wednesday evening. If this occurs, it may open the door to fog potential. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...DSA LONG TERM...DSA AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1149 PM CDT Tue Apr 14 2015 .DISCUSSION... Issued at 316 PM CDT TUE APR 14 2015 A slow moving upper-level low is meandering northeast through Kansas based on latest satellite and radar imagery. This is resulting in isolated to scattered showers over southern Missouri to slowly lift northward. This trend will continue tonight and arranged PoPs to build north from late this afternoon through the overnight. Chances still look rather low and have kept PoPs below 30% through the night and into the day Wednesday. Short-range higher resolution models, like the WRF-ARW and NMM as well as the RUC and HRRR all show relatively spotty shower activity through the night. But overall, isolated to scattered showers are expected to build northward tonight and then shift east through the day tomorrow as the upper-level low opens up and moves away to the east. The focus will then shift to the large upper-level trough building into the Intermountain West. First, there is considerable uncertainty with how this system will evolve and this is mainly due to the potential for it to cut off and get stuck between the polar jet to the north and the subtropical jet to the south. This is the scenario the ECMWF and the GEM depict. However, GFS is not as strong with the cutting off and as a result pushes east quicker. That said, it looks like this system will remain to our west through at least the end of the week, and possibly into the early part of next week, allowing for southerly low-level flow to build moisture northward. This means we`ll see the chances for showers and thunderstorms through much, if not all of, the extended portion of the forecast. It doesn`t look like we`ll see any widespread precipitation on any given day, rather isolated to scattered showers and storms. Additionally, the threat of severe weather looks low for our area as there never really seems to be aligning of instability with stronger shear. Regarding temperatures, with increased cloud coverage/ precipitation potential for each day, highs look to be fairly close to normal with temperatures in the upper 60s to lower 70s. Later in the period, as the upper low is expected to be closer to the region, temperatures may top out in the mid to upper 60s. The normal high for the Kansas City area through this period is in the upper 60s. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1149 PM CDT TUE APR 14 2015 Latest observations still showing MVFR conditions down across Arkansas late this evening. As a result...have delayed onset of MVFR restrictions until after 12z. Through the remainder of the overnight...non-restricting -SHRA activity to impact area terminals...with this trend continuing through much of the day before conditions begin to dry after 22z. Once MVFR low stratus sets in after 14z...expect MVFR restrictions through the conclusion of the fcst period. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...CDB AVIATION...32
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
957 AM MDT WED APR 15 2015 .UPDATE... LARGE UPPER LOW MOVING OUT OF UTAH INTO COLORADO CONTINUES TO PROVIDE STRONG UPPER LEVEL DIVERGENCE ACROSS SOUTHERN MONTANA AND NORTHERN WYOMING. RADAR SHOWING BULK OF WET SNOW ACROSS MUSSELSHELL...YELLOWSTONE...AND BIG HORN COUNTIES...AS WELL AS THE BEARTOOTH FOOTHILLS LOCATIONS. HOWEVER...THE INTENSITY OF THE SNOW HAS DECREASED QUITE A BIT FOR MOST LOCATIONS...AND EVEN WITH SOME HEAVIER BURSTS...IT WILL BE DIFFICULT TO GET ANY ADDITIONAL SNOW ACCUMULATIONS THIS TIME OF YEAR ESPECIALLY ON ROAD SURFACES. AS A RESULT...I DID CANCEL THE WINTER WEATHER ADVISORY FOR YELLOWSTONE...STILLWATER AND EASTERN CARBON COUNTIES. WEB CAMS SHOWING A BIT HEAVIER SNOW ACROSS THE RED LODGE AREA SO WILL KEEP THE ADVISORY GOING FOR THE FOOTHILLS INTO THIS AFTERNOON. AS THE UPPER LOW SHIFTS SOUTH AND EAST TODAY...THE PRECIP WILL ALSO SHIFT SOUTH AND EAST ACROSS SHERIDAN COUNTY AND OUR SOUTHEAST ZONES. AS A MATTER OF FACT...SNOW HAS JUST BEGUN AT SHERIDAN WITH 2 MILES VISIBILITY ALONG WITH NORTHWEST WINDS GUSTING NEAR 40 MPH. OTHER CHANGES WERE TO INCREASE POPS TO LIKELY FOR THE BILLINGS AREA THIS AFTERNOON AS THE HRRR MODEL SHOWS PRECIP CONTINUING WELL INTO THIS AFTERNOON. ALL UPDATES HAVE BEEN SENT. HOOLEY && .SHORT TERM...VALID FOR TDY AND THU... DYNAMIC SYSTEM WILL CONTINUE TO IMPACT THE AREA TODAY. THE UPPER LOW HAS MOVED INTO NORTHERN UTAH WITH STRONG UPPER DIFFLUENCE WORKING INTO SOUTH CENTRAL MONTANA. THIS DIFFLUENCE HAS BEEN STRONG ENOUGH TO PRODUCE A BAND OF MODERATE TO HEAVY SNOW SHOWERS OVER PARTS OF SOUTH CENTRAL MONTANA...DESPITE DRY AIR AT MID LEVELS ENTRAINING INTO THE SYSTEM. ISSUED A WINTER WEATHER ADVISORY FOR YELLOWSTONE COUNTY AND INCLUDED STILLWATER AND EASTERN CARBON AS A BAND OF AGGRESSIVE SNOW SHOWERS WERE MOVING INTO THE AREA. THIS BAND WILL MOVE THROUGH EARLY THIS MORNING AND COULD PRODUCE SNOW RATES OF A HALF INCH TO AN INCH AN HOUR FOR 2 TO 4 HOURS. GRASSY SURFACES HAVE ALREADY ACCUMULATED A HALF INCH AT THE OFFICE AND ROADS WERE BECOMING SLUSH COVERED. ROAD CONDITIONS WILL GET WORSE THROUGH 6 AM WITH THE HEAVIEST SNOW MOVING IN. THE SNOW WILL MIX WITH SOME RAIN AND TAPER OFF IN BILLINGS BY MID MORNING. SO THE MAIN EVENT FOR YELLOWSTONE COUNTY WILL BE EARLY THIS MORNING. DROPPED PARK COUNTY OUT OF THE WINTER WEATHER ADVISORY. SNOW HAS BEEN SPORADIC AND HRRR FOCUSES THE ASCENT EAST OF LIVINGSTON. LIVINGSTON WILL STILL GET SNOW SHOWERS THIS MORNING...BUT THE HEAVIER SNOW SHOULD BE EAST OF TOWN AND MORE ALIGNED WITH THE BEARTOOTH AND RED LODGE FOOTHILLS. SPEAKING OF THE FOOTHILLS...THESE LOCATIONS LOOK GOOD FOR ADDITIONAL SNOWFALL THIS MORNING AND WILL KEEP THE ADVISORY GOING. PRECIPITATION WAS FILLING IN OVER THE WESTERN PART OF SOUTHERN BIG HORN COUNTY AT THE MOMENT AND EXPECT THIS AREA...ALONG WITH SHERIDAN COUNTY...TO FILL IN FURTHER THIS MORNING. BUMPED POPS FOR THESE LOCATIONS AND KEPT THE WINTER WEATHER ADVISORY IN PLACE. THE BIGHORN MOUNTAINS WILL CONTINUE TO PICK UP SNOW TODAY AS WELL AND ADVISORY THERE LOOKS GOOD. THE SYSTEM SHIFTS EAST SLOWLY TODAY AND PRECIPITATION WILL TAPER OFF FROM WEST TO EAST THROUGH THE LATE MORNING AND AFTERNOON HOURS. BUMPED POPS BACK UP OVER PARTS OF SOUTH CENTRAL MONTANA WITH A SLOWER EASTWARD PUSH OF THE SYSTEM. RAISED POPS OVER THE EAST. THE EAST WILL BE A TOUGH CALL TODAY AS THE MAJORITY OF THEIR PRECIPITATION WILL FALL IN THE DAYTIME AND THIS COULD LIMIT SNOW POTENTIAL. GFS KEEPS 850MB TEMPERATURES ABOVE ZERO THERE TODAY SO KEPT THE PRECIPITATION MOSTLY RAIN. PRECIPITATON SHOULD TAPER OFF FOR MOST LOCATIONS TONIGHT. THE ONE LOCATION TO WATCH IS THE FAR SOUTHEAST CORNER. THE GFS SWINGS SOME ENERGY IN THERE FROM THE SOUTHEAST AS IT WRAPS AROUND AN ELONGATED UPPER TROUGH FROM NORTHEAST WYOMING INTO NORTHERN NEW MEXICO. RAISED POPS AND QPF AMOUNTS. LOOKS TO BE MOSTLY RAIN WITH 850MB TEMPERATURES ABOVE ZERO. THURSDAY WILL BE DRY AND WARMER THE AS SYSTEM RESPONSIBLE FOR THE PRECIPITATION TODAY SINKS SOUTH AND A WEST TO EAST RIDGE AXIS SLIDES INTO MONTANA. TWH .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... FLAT UPPER RIDGING FRI THROUGH FRI NIGHT WILL GIVE WAY TO A SHORTWAVE AND ASSOCIATED COLD FRONT PUSHING SE THROUGH THE AREA SAT THROUGH SAT NIGHT. HIGHS ON FRI WILL BE IN THE 60S...WITH 70S EXPECTED ON SAT AHEAD OF THE FRONT. MODEL DIFFERENCES IN QPF PLACEMENT CONTINUED ALONG THE FRONT ON SAT. HAVE ADDED LOW POPS TO THE SE ZONES PER THE ECMWF. KEPT POPS ACROSS THE AREA SAT NIGHT UNDER THE UPPER TROUGH. THE FORECAST AREA WILL REMAIN UNDER CYCLONIC FLOW THROUGH THE REMAINDER OF THE PERIOD AS AN UPPER LOW SHIFTS E THROUGH S CANADA. THERE WERE MODEL DIFFERENCES IN THE HANDLING OF SHORTWAVES ROTATING AROUND THE BACKSIDE OF THE UPPER LOW THROUGH THE AREA. HOWEVER...THERE WAS AGREEMENT IN A DRIER PERIOD SUN THROUGH MON SO HAVE GONE WITH LOW POPS OR POPS OVER AND NEAR THE MOUNTAINS. KEPT MON NIGHT MOSTLY DRY...EVEN THROUGH THE GFS TRIED TO BRING A COLD FRONT INTO THE AREA. CONTINUED THE IDEA OF LOW POPS THROUGH TUE NIGHT USING A MODEL BLEND. BOTH MODELS HAD A BACKDOOR FRONT MOVING INTO THE AREA FOR WED WITH VARYING QPF AMOUNTS. AGAIN USED A MODEL BLEND FOR POPS. SUN WILL BE COOLER BEHIND THE FRONT...THEN TEMPERATURES WILL REBOUND A BIT FOR MON. THERE WAS POOR MODEL AGREEMENT ON TUE TEMPERATURES DUE TO THE COLDER AIR ON THE GFS WITH THE FRONT...SO USED A MODEL BLEND. TEMPERATURES WILL BE SEASONABLE ON WED. ARTHUR && .AVIATION... EXPECT MVFR TO IFR CONDITIONS TO CONTINUE THROUGH MUCH OF THE DAY ACROSS THE AREA. LIGHT SNOW WILL CONTINUE AT ALL TAF SITES...TRANSITIONING TO A MIX FROM BILLINGS EAST THIS AFTERNOON. LOCALIZED LIFR CONDITIONS ARE POSSIBLE IN HEAVIER BANDS OF SNOW. MOUNTAIN OBSCURATION WILL ALSO CONTINUE THROUGH THE DAY. EXPECT CONDITIONS BE BEGIN IMPROVING THIS EVENING AND OVERNIGHT FROM WEST TO EAST. REIMER && .PRELIMINARY POINT TEMP/POPS... TDY THU FRI SAT SUN MON TUE ------------------------------------------------------- BIL 045 032/059 037/064 041/068 039/059 037/061 038/061 7/W 10/U 00/U 02/W 22/W 21/B 12/W LVM 044 025/058 031/064 038/065 034/057 033/060 036/061 6/W 00/U 00/U 02/W 22/W 21/B 12/W HDN 046 032/060 035/066 038/070 036/060 034/062 035/062 8/W 20/B 00/U 01/B 22/W 11/B 11/N MLS 051 034/061 036/067 040/072 036/058 034/058 034/058 7/W 40/U 00/U 01/U 22/W 11/N 11/N 4BQ 046 034/055 031/065 037/068 035/058 032/058 032/058 8/W 51/B 00/U 01/U 22/W 11/N 12/W BHK 053 034/059 033/066 038/070 035/057 031/055 030/053 7/W 42/W 00/U 01/U 22/W 11/N 22/W SHR 040 030/054 030/061 036/065 034/056 032/057 033/058 9/W 51/B 00/U 01/B 33/W 22/W 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR ZONE 38. WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 PM MDT THIS EVENING FOR ZONES 56-66. WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR ZONES 98-99. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
327 AM MDT WED APR 15 2015 .SHORT TERM...VALID FOR TDY AND THU... DYNAMIC SYSTEM WILL CONTINUE TO IMPACT THE AREA TODAY. THE UPPER LOW HAS MOVED INTO NORTHERN UTAH WITH STRONG UPPER DIFFLUENCE WORKING INTO SOUTH CENTRAL MONTANA. THIS DIFFLUENCE HAS BEEN STRONG ENOUGH TO PRODUCE A BAND OF MODERATE TO HEAVY SNOW SHOWERS OVER PARTS OF SOUTH CENTRAL MONTANA...DESPITE DRY AIR AT MID LEVELS ENTRAINING INTO THE SYSTEM. ISSUED A WINTER WEATHER ADVISORY FOR YELLOWSTONE COUNTY AND INCLUDED STILLWATER AND EASTERN CARBON AS A BAND OF AGGRESSIVE SNOW SHOWERS WERE MOVING INTO THE AREA. THIS BAND WILL MOVE THROUGH EARLY THIS MORNING AND COULD PRODUCE SNOW RATES OF A HALF INCH TO AN INCH AN HOUR FOR 2 TO 4 HOURS. GRASSY SURFACES HAVE ALREADY ACCUMULATED A HALF INCH AT THE OFFICE AND ROADS WERE BECOMING SLUSH COVERED. ROAD CONDITIONS WILL GET WORSE THROUGH 6 AM WITH THE HEAVIEST SNOW MOVING IN. THE SNOW WILL MIX WITH SOME RAIN AND TAPER OFF IN BILLINGS BY MID MORNING. SO THE MAIN EVENT FOR YELLOWSTONE COUNTY WILL BE EARLY THIS MORNING. DROPPED PARK COUNTY OUT OF THE WINTER WEATHER ADVISORY. SNOW HAS BEEN SPORADIC AND HRRR FOCUSES THE ASCENT EAST OF LIVINGSTON. LIVINGSTON WILL STILL GET SNOW SHOWERS THIS MORNING...BUT THE HEAVIER SNOW SHOULD BE EAST OF TOWN AND MORE ALIGNED WITH THE BEARTOOTH AND RED LODGE FOOTHILLS. SPEAKING OF THE FOOTHILLS...THESE LOCATIONS LOOK GOOD FOR ADDITIONAL SNOWFALL THIS MORNING AND WILL KEEP THE ADVISORY GOING. PRECIPITATION WAS FILLING IN OVER THE WESTERN PART OF SOUTHERN BIG HORN COUNTY AT THE MOMENT AND EXPECT THIS AREA...ALONG WITH SHERIDAN COUNTY...TO FILL IN FURTHER THIS MORNING. BUMPED POPS FOR THESE LOCATIONS AND KEPT THE WINTER WEATHER ADVISORY IN PLACE. THE BIGHORN MOUNTAINS WILL CONTINUE TO PICK UP SNOW TODAY AS WELL AND ADVISORY THERE LOOKS GOOD. THE SYSTEM SHIFTS EAST SLOWLY TODAY AND PRECIPITATION WILL TAPER OFF FROM WEST TO EAST THROUGH THE LATE MORNING AND AFTERNOON HOURS. BUMPED POPS BACK UP OVER PARTS OF SOUTH CENTRAL MONTANA WITH A SLOWER EASTWARD PUSH OF THE SYSTEM. RAISED POPS OVER THE EAST. THE EAST WILL BE A TOUGH CALL TODAY AS THE MAJORITY OF THEIR PRECIPITATION WILL FALL IN THE DAYTIME AND THIS COULD LIMIT SNOW POTENTIAL. GFS KEEPS 850MB TEMPERATURES ABOVE ZERO THERE TODAY SO KEPT THE PRECIPITATION MOSTLY RAIN. PRECIPITATON SHOULD TAPER OFF FOR MOST LOCATIONS TONIGHT. THE ONE LOCATION TO WATCH IS THE FAR SOUTHEAST CORNER. THE GFS SWINGS SOME ENERGY IN THERE FROM THE SOUTHEAST AS IT WRAPS AROUND AN ELONGATED UPPER TROUGH FROM NORTHEAST WYOMING INTO NORTHERN NEW MEXICO. RAISED POPS AND QPF AMOUNTS. LOOKS TO BE MOSTLY RAIN WITH 850MB TEMPERATURES ABOVE ZERO. THURSDAY WILL BE DRY AND WARMER THE AS SYSTEM RESPONSIBLE FOR THE PRECIPITATION TODAY SINKS SOUTH AND A WEST TO EAST RIDGE AXIS SLIDES INTO MONTANA. TWH .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... FLAT UPPER RIDGING FRI THROUGH FRI NIGHT WILL GIVE WAY TO A SHORTWAVE AND ASSOCIATED COLD FRONT PUSHING SE THROUGH THE AREA SAT THROUGH SAT NIGHT. HIGHS ON FRI WILL BE IN THE 60S...WITH 70S EXPECTED ON SAT AHEAD OF THE FRONT. MODEL DIFFERENCES IN QPF PLACEMENT CONTINUED ALONG THE FRONT ON SAT. HAVE ADDED LOW POPS TO THE SE ZONES PER THE ECMWF. KEPT POPS ACROSS THE AREA SAT NIGHT UNDER THE UPPER TROUGH. THE FORECAST AREA WILL REMAIN UNDER CYCLONIC FLOW THROUGH THE REMAINDER OF THE PERIOD AS AN UPPER LOW SHIFTS E THROUGH S CANADA. THERE WERE MODEL DIFFERENCES IN THE HANDLING OF SHORTWAVES ROTATING AROUND THE BACKSIDE OF THE UPPER LOW THROUGH THE AREA. HOWEVER...THERE WAS AGREEMENT IN A DRIER PERIOD SUN THROUGH MON SO HAVE GONE WITH LOW POPS OR POPS OVER AND NEAR THE MOUNTAINS. KEPT MON NIGHT MOSTLY DRY...EVEN THROUGH THE GFS TRIED TO BRING A COLD FRONT INTO THE AREA. CONTINUED THE IDEA OF LOW POPS THROUGH TUE NIGHT USING A MODEL BLEND. BOTH MODELS HAD A BACKDOOR FRONT MOVING INTO THE AREA FOR WED WITH VARYING QPF AMOUNTS. AGAIN USED A MODEL BLEND FOR POPS. SUN WILL BE COOLER BEHIND THE FRONT...THEN TEMPERATURES WILL REBOUND A BIT FOR MON. THERE WAS POOR MODEL AGREEMENT ON TUE TEMPERATURES DUE TO THE COLDER AIR ON THE GFS WITH THE FRONT...SO USED A MODEL BLEND. TEMPERATURES WILL BE SEASONABLE ON WED. ARTHUR && .AVIATION... A STRONG COLD FRONT PUSHED E THROUGH THE AREA OVERNIGHT...USHERING IN GUSTY NW SURFACE WINDS AND RAIN AND SNOW. WINDS WILL GUST BETWEEN 25 AND 35 KT THROUGH THE DAY AND DIMINISH DURING THE EVENING. THERE WILL BE A MIX OF RAIN AND SNOW OVER THE AREA THIS MORNING THAT WILL PUSH TO THE E AND S OF KBIL THIS AFTERNOON. CONDITIONS WILL BE MVFR TO IFR WITH AREAS OF LIFR IN THE PRECIPITATION. CHANCES FOR RAIN AND SNOW WILL LINGER E AND S OF KBIL TONIGHT WITH MVFR/IFR CONDITIONS. CONDITIONS WILL IMPROVE TO VFR FROM KBIL W. THE MOUNTAINS WILL BE MAINLY OBSCURED TODAY. THE OBSCURATIONS WILL DECREASE FROM W TO E TONIGHT. ARTHUR && .PRELIMINARY POINT TEMP/POPS... TDY THU FRI SAT SUN MON TUE ------------------------------------------------------- BIL 045 032/059 037/064 041/068 039/059 037/061 038/061 7/W 10/U 00/U 02/W 22/W 21/B 12/W LVM 044 025/058 031/064 038/065 034/057 033/060 036/061 6/W 00/U 00/U 02/W 22/W 21/B 12/W HDN 046 032/060 035/066 038/070 036/060 034/062 035/062 8/W 20/B 00/U 01/B 22/W 11/B 11/N MLS 051 034/061 036/067 040/072 036/058 034/058 034/058 7/W 40/U 00/U 01/U 22/W 11/N 11/N 4BQ 046 034/055 031/065 037/068 035/058 032/058 032/058 8/W 51/B 00/U 01/U 22/W 11/N 12/W BHK 053 034/059 033/066 038/070 035/057 031/055 030/053 7/W 42/W 00/U 01/U 22/W 11/N 22/W SHR 040 030/054 030/061 036/065 034/056 032/057 033/058 9/W 51/B 00/U 01/B 33/W 22/W 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MDT TODAY FOR ZONES 34-35-39. WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR ZONE 38. WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 PM MDT THIS EVENING FOR ZONES 56-66. WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR ZONES 98-99. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
334 PM CDT WED APR 15 2015 .SHORT TERM...(TONIGHT) ISSUED AT 309 PM CDT WED APR 15 2015 LARGE SCALE PATTERN PER WV IMAGERY THIS AFTN SHOWING FAST ZONAL FLOW WITH SEVERAL EMBEDDED WAVES EXTENDING ACROSS SRN CANADA WITH A LARGE CLOSED OFF CIRCULATION SITUATED OVER THE GREAT BASIN. AT THE SFC...LLVL MOISTURE RETURN IS UNDERWAY WITH DEW POINTS INCREASING OVER THE LOWER/MID MS VLY REGION. RUC13 SHOWING BNDRY LYR MOISTURE ADV CONTINUING THRU TONIGHT WITH PW VALUES INCREASING TO AROUND AN INCH OVER THE CWA. TSTM DEVELOPMENT PROGGED TO OCCUR OVER CNTRL KS/S- CNTRL NEB LATER THIS EVENING WITHIN AREA OF ELEVATED INSTABILITY/NOSE OF LLVL JET...THEN EXPAND NEWD INTO THE WRN CWA SOMETIME AFT MIDNIGHT AS UPGLIDE INCREASES ALONG 300K SFC. PLAN ON ONLY MAKING MINOR TWEAKS AT THIS POINT AS GOING FCST IS IN DECENT SHAPE DEPICTING POPS INCREASING FROM WEST TO EAST DURING THE OVERNIGHT HOURS. .LONG TERM...(THURSDAY THROUGH WEDNESDAY) ISSUED AT 309 PM CDT WED APR 15 2015 MAIN FORECAST CONCERN WILL BE PROGRESSION OF WESTERN CONUS UPPER LOW AND ITS IMPACTS AS IT SLIDE ACROSS THE CENTRAL PLAINS. BY THURSDAY MORNING...THE WESTERN CONUS UPPER LOW WILL BE CENTERED ON TOP OF THE FOUR CORNERS REGION. LEE SIDE SFC LOW REFLECTION IS FORECAST TO BE FAIRLY BROAD ACROSS THE TEXAS PANHANDLE WITH AN INVERTED TROUGH EXTENDING NORTHEAST ACROSS WESTERN KS AND INTO WESTERN NEBRASKA. PRECIPITATION WILL CONTINUE TO SPREAD EAST INTO OUR WESTERN CWA...BECOMING LIKELY LATER IN THE DAY THURSDAY AS BROAD SCALE ASCENT INCREASES WITH LEAD SHORTWAVE ENERGY. THE UPPER LOW WILL SLOWLY MOVE INTO THE SOUTHERN PLAINS AND IS FORECAST TO OPEN UP THROUGH THE WEEKEND PROVIDING CONTINUED BROAD SCALE VERTICAL MOTION THROUGH SUNDAY. LOW LEVEL MOISTURE ALREADY IN PLACE ACROSS THE SOUTHERN PLAINS WILL CONTINUE TO STREAM NORTHWARD AS THE SFC LOW PRESSURE CENTER BETTER ORGANIZES ACROSS EASTERN COLORADO BY FRIDAY MORNING. PW`S WILL REMAIN ABOVE 1" THROUGH THE PERIOD. ALTHOUGH RAIN IS LIKELY AT TIMES THROUGH SUNDAY...WE WILL HAVE A FEW INTERMITTENT BREAKS BUT TOO DIFFICULT TO DETERMINE AT THIS POINT WITH SUCH SLOW PROGRESSION OF THE UPPER LOW. BEST CHANCE FOR THUNDERSTORMS LOOKS TO BE THURSDAY AND FRIDAY AFTERNOON...ESPECIALLY ACROSS THE SOUTHERN CWA. HAVE INCLUDED ISOLATED THUNDER MENTION THROUGH MUCH OF THE TIME PERIOD. BY MID DAY SUNDAY...THE UPPER TROUGH AXIS SHOULD BE EAST OF THE CWA...ALLOWING PCPN TO END FROM WEST TO EAST. THE 12Z ECMWF REALLY WRAPS THIS SYSTEM UP...WITH NORTHWESTERLY 850MB WINDS ON THE ORDER OF 65KTS SUNDAY AFTERNOON. 850MB TEMPERATURES DO APPROACH THE 0C MARK OF THE LATEST ECMWF SO WILL NEED TO WATCH THAT CAREFULLY FOR ANY CHANGE OVER IN PCPN TYPES SUNDAY. MUCH COOLER NORTHWESTERLY FLOW WILL PERSIST ACROSS THE AREA THROUGH EARLY NEXT WEEK WHICH MAY PUT TEMPERATURES INTO THE BELOW NORMAL CATEGORY. A FEW MINOR WAVES MAY MOVE THROUGH THIS FLOW PROVIDING SMALL CHANCES FOR PCPN. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1225 PM CDT WED APR 15 2015 MIX OF LOW END VFR/MVFR CIGS BEING REPORTED OVER ERN NEB THIS AFTN. MEANWHILE...REGIONAL MOSAIC WAS SHOWING NARROW LINE OF SHRA EXTENDING NWD THRU WRN MO INTO WRN IA. PCPN SHOULD GENERALLY REMAIN EAST OF THE MO RIVER BEFORE DISSIPATING LATER THIS AFTN. ACTIVITY THOUGH CLOSE ENOUGH TO WARRANT TEMPO GROUP AT KOMA. OTHERWISE...EXPECT MIX OF LOW END VFR/MVFR CONDITIONS WILL PERSIST THRU THE MAJORITY OF THE FCST PD AT ALL TERMINALS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE LONG TERM...KERN AVIATION...DEE
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1205 PM CDT WED APR 15 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 420 AM CDT WED APR 15 2015 QUIET CONDITIONS REMAIN IN PLACE ACROSS THE CWA THIS MORNING...WITH UPPER AIR AND SATELLITE DATA SHOWING AN UPPER LEVEL DISTURBANCE SLOWLY SLIDING NE ACROSS CENTRAL/ERN PORTIONS OF KS/NE. THIS DISTURBANCE IS GRADUALLY BECOMING MORE PHASED WITH A STRONGER UPPER LEVEL LOW PRESSURE SYSTEM...WHICH IS CURRENTLY LOCATED OVER NRN PORTIONS OF UTAH. REGIONAL RADAR SHOWS A FEW SHOWERS/SPRINKLES HAVE DEVELOPED OVER FAR SERN NEB/ERN KS...BUT THE CWA REMAINS DRY. AT THE SFC...SERLY WINDS ARE IN PLACE WITH SPEEDS IN THE 5 TO 15 MPH RANGE...SET UP BETWEEN HIGH PRESSURE OVER THE GREAT LAKES AND A TROUGH OF LOW PRESSURE DRAPED ALONG THE HIGH PLAINS. AS THIS UPPER LEVEL DISTURBANCE CONTINUES PUSHING NE EARLY THIS MORNING ALONG WITH THE SERLY LOWER LEVEL FLOW...SATELLITE IMAGERY SHOWS INCREASING CLOUD COVER MOVING NORTH AS WELL. MOST OF THE CWA IS CURRENTLY MOSTLY CLEAR...BUT SERN PORTIONS ARE SEEING MORE SKY COVER. LOOKING TO THE DAYTIME HOURS TODAY...KEPT THE FORECAST DRY...AS THE DISTURBANCE IN THE AREA CONTINUES TO WEAKEN...BUT THE MAIN UPPER LEVEL LOW IS STILL WELL OF TO THE WEST. EXPECTING THAT UPWARD TREND IN SKY COVER TO CONTINUE THROUGH THE DAY...AND WHILE THERE IS LITTLE CHANGE IN THE WIND DIRECTION...ARE EXPECTING ANOTHER BREEZY DAY. MODELS ARE SHOWING SFC LOW PRESSURE TO DEVELOP OVER ERN PORTIONS OF COLORADO...AND THE RESULTING TIGHTER PRESSURE GRADIENT IS EXPECTED TO RESULT IN SPEEDS CLIMBING INTO THE 15 TO 25 MPH RANGE. BUMPED UP HIGHS A TOUCH FOR TODAY...NOT AS HIGH AS THE RAP SUGGESTS...BUT CLOSE TO THE MET/MAV...WHICH GIVES MID 60S FOR MOST OF THE CWA. PRECIPITATION CHANCES RETURN TO THE FORECAST FOR THIS EVENING AND OVERNIGHT...BUT CONFIDENCE REMAINS ON THE LOWER SIDE WITH HOW THINGS WILL EVOLVE...AS THERE CONTINUES TO BE SOME PRETTY NOTABLE DIFFERENCES BETWEEN MODELS. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE HIGH PLAINS LATER THIS AFTERNOON...PUSHING FURTHER EAST THIS EVENING/OVERNIGHT AS A PIECE OF UPPER LEVEL SHORTWAVE ENERGY MOVES INTO THE REGION. THERE IS SOME QUESTION WITH THE OVERALL COVERAGE OF THIS ACTIVITY AS IT MOVES INTO THE AREA...AND HOW QUICKLY IT DOES SO. WHILE SOME ADJUSTMENTS WERE MADE TO TIMING/LOCATION OF POPS...NO SIGNIFICANT CHANGES WERE DONE. CONTINUE TO HAVE POPS STARTING AT 00Z...BUT SOME MODELS SUGGEST THAT IS TOO EARLY...THAT IT MAY BE CLOSER TO 03Z BEFORE WRN PORTIONS OF THE CWA ARE AFFECTED. ACTIVITY IS EXPECTED TO CONTINUE SHIFTING E/NE...BUT MODELS DIFFER WITH HOW FAR THINGS GET PRIOR TO 12Z. IT RANGES FROM OUTPUT LIKE THE 4KM/ECMWF SHOWING VERY LITTLE MAKING IT IN OR MOVING THROUGH...VS THE GFS/SREF WHICH SHOW QPF FURTHER INTO THE N/NERN AREAS. EARLY ON...THERE IS THE CHANCE FOR A FEW OF THOSE THUNDERSTORMS ACROSS FAR WRN AREAS TO BE ON THE STRONG SIDE...BUT THE 00Z RUN OF MODELS GENERALLY SHOWED MUCAPE VALUES TOPPING OUT IN THE 500-1000 J/KG RANGE. THE SPC DAY 1 OUTLOOK CLIPS WRN PORTIONS OF THE CWA WITH A MARGINAL RISK TODAY...WILL KEEP THE MENTION OF STRONG STORMS IN THE HWO. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 420 AM CDT WED APR 15 2015 THE BIG WEATHER STORY WILL CONTINUE TO REVOLVE AROUND THE INCREASINGLY LIKELY CHANCE OF APPRECIABLE RAINFALL THURSDAY THROUGH SATURDAY NIGHT. THE MOST RECENT 00Z RUNS OF THE ECMWF AND GFS SHOW QPF TOTALS OF 1 TO 3 INCHES ACROSS THE ENTIRE FORECAST AREA IN THE PERIOD BEGINNING THURSDAY AND ENDING AT 6 AM SUNDAY MORNING. GIVEN THE PROLONGED OFF AND ON AGAIN SEVERAL DAYS OF RAIN...WOULD NOT BE SURPRISED SO SEE A FEW 3 DAY RAINFALL TOTALS IN THE 4 TO 5 INCH RANGE...ALTHOUGH MOST AREAS ARE MORE LIKELY TO SEE SOMETHING CLOSER TO THE 1 TO 3 INCHES INDICATED BY THE MODELS. THE LOCALLY HIGHER TOTALS WILL BE POSSIBLE WITHIN AREAS OF STRONGER CONVECTION AS INSTABILITY WILL BE MORE THAN SUFFICIENT FOR THUNDERSTORMS ON AT LEAST THURSDAY AND FRIDAY. INSTABILITY BEGINS TO REALLY DECREASE BY SATURDAY. NORMALLY THESE KIND OF RAINS WOULD SPARK FLOODING CONCERNS. ALTHOUGH WE CAN NOT RULE OUT SOME LOCALIZED FLOODING...THE RAIN WILL COME ON AND OFF AGAIN OVER SEVERAL DAYS AND WE HAVE BEEN ABNORMALLY DRY THUS GREATLY LIMITING ANY FLOODING THREAT DESPITE THE POTENTIAL FOR HEAVY RAINFALL AMOUNTS. ALL OF THE EXPECTED PRECIPITATION IS A RESULT OF A SIGNIFICANT UPPER LEVEL STORM SYSTEM THAT WILL DIG ACROSS THE ROCKIES...BECOME CUT OFF...AND THEN SLOWLY TRACKS EAST THROUGH THE PLAINS. FORECAST MODELS ARE IN GOOD AGREEMENT THAT THIS UPPER LOW WILL TRACK VERY SLOWLY ACROSS THE PLAINS DUE TO BEING CUT OFF FROM THE NORTHERN STREAM OF THE UPPER JET. THIS WILL ALLOW PLENTY OF TIME FOR GULF MOISTURE TO STREAM NORTHWARD THROUGH THE PLAINS AND GIVE US A PROLONGED WINDOW OF PRECIPITATION CHANCES. FORECAST MODELS AND THEIR ENSEMBLES ARE COMING INTO BETTER AGREEMENT WITH THE OVERALL TRACK OF THE LARGE SCALE SYNOPTIC SYSTEM...WHICH AS STATED EARLIER IS LOOKING PRETTY WET FOR THE SOUTHERN AND CENTRAL PLAINS. THERE IS STILL PLENTY OF UNCERTAINTY IN HOW THINGS WILL EVOLVE IN THE MESOSCALE AND STORM SCALE WITH REGARD TO TIMING OF MULTIPLE CONVECTIVE LINES...AND EVEN POSSIBLE MCS ACTIVITY. THURSDAY AND FRIDAY...FORECAST MODELS VARY ON HOW MUCH INSTABILITY WE WILL HAVE TO WORK WITH...BUT THE GENERAL CONSENSUS IS THAT THERE WILL BE AT LEAST ENOUGH INSTABILITY FOR GENERAL THUNDERSTORMS THURSDAY AND FRIDAY. THE 00Z GFS ACTUALLY HAS OVER 1000 J/KG OF SBCAPE BOTH THURSDAY AND FRIDAY AFTERNOON OVER PRIMARILY OUR KANSAS COUNTIES. DEEP LAYER SHEAR VALUES SHOULD BE AROUND 30 KTS IF NOT HIGHER AND THUS A FEW THUNDERSTORMS COULD BECOME SEVERE EITHER DAY WITH THE HIGHER LIKELIHOOD OF A FEW SEVERE THUNDERSTORMS BEING ACROSS OUR KANSAS COUNTIES. FORECAST MODELS HAVE CONSISTENTLY BEEN CALLING FOR HIGHS IN THE 60S DESPITE CLOUDY SKIES AND OFF AND ON AGAIN RAIN SO WILL CONTINUE TO KEEP THESE 60S IN THE FORECAST. SATURDAY AND SUNDAY...THE UPPER SYSTEM WILL FINALLY BE EJECTING INTO THE PLAINS AT SOME POINT ON SATURDAY AND THIS IS WHEN THE FORECAST MODELS START TO DIVERGE. OVERALL MOST MODELS STILL GIVE US A GOOD CHANCE OF SHOWERS ON SATURDAY WITH ABUNDANT MOISTURE STREAMING NORTH THROUGH THE PLAINS. HOWEVER...BY SUNDAY THE UPPER LOW WILL HAVE WEAKENED AND POSSIBLY EVEN TRACKED EAST OF OUR AREA THUS THE PRECIPITATION CHANCES ARE LOWER AND MAY NEED TO BE EVEN LOWER OR TAKEN OUT ALTOGETHER DEPENDING ON HOW THINGS EVOLVE IN THE COMING DAYS. INSTABILITY IS GENERALLY WEAKER THAN THE PRECEDING DAYS AND THUS SEVERE WEATHER CURRENTLY SEEMS UNLIKELY UNLESS SOMETHING WERE TO CHANGE. HIGHS SHOULD STILL BE IN THE 60S. MONDAY AND TUESDAY...MOST AREAS SHOULD BE DRY WITH HIGHS IN THE 60S. && .AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1142 AM CDT WED APR 15 2015 VARYING CLOUD COVER DURING THE AFTERNOON WILL THICKEN AND LOWER THIS EVENING AND TONIGHT...DROPPING TO MVFR...IFR AND POTENTIALLY LIFR. MODELS HAVE SLOWED DOWN TIMING OF THE ARRIVAL FOR CONVECTION...TRENDING MORE SO TOWARD LATE OVERNIGHT OR TOWARD THURSDAY MORNING AND HAVE CARRIED VCTS INTO THURSDAY. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADP LONG TERM...WESELY AVIATION...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
639 AM CDT WED APR 15 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 420 AM CDT WED APR 15 2015 QUIET CONDITIONS REMAIN IN PLACE ACROSS THE CWA THIS MORNING...WITH UPPER AIR AND SATELLITE DATA SHOWING AN UPPER LEVEL DISTURBANCE SLOWLY SLIDING NE ACROSS CENTRAL/ERN PORTIONS OF KS/NE. THIS DISTURBANCE IS GRADUALLY BECOMING MORE PHASED WITH A STRONGER UPPER LEVEL LOW PRESSURE SYSTEM...WHICH IS CURRENTLY LOCATED OVER NRN PORTIONS OF UTAH. REGIONAL RADAR SHOWS A FEW SHOWERS/SPRINKLES HAVE DEVELOPED OVER FAR SERN NEB/ERN KS...BUT THE CWA REMAINS DRY. AT THE SFC...SERLY WINDS ARE IN PLACE WITH SPEEDS IN THE 5 TO 15 MPH RANGE...SET UP BETWEEN HIGH PRESSURE OVER THE GREAT LAKES AND A TROUGH OF LOW PRESSURE DRAPED ALONG THE HIGH PLAINS. AS THIS UPPER LEVEL DISTURBANCE CONTINUES PUSHING NE EARLY THIS MORNING ALONG WITH THE SERLY LOWER LEVEL FLOW...SATELLITE IMAGERY SHOWS INCREASING CLOUD COVER MOVING NORTH AS WELL. MOST OF THE CWA IS CURRENTLY MOSTLY CLEAR...BUT SERN PORTIONS ARE SEEING MORE SKY COVER. LOOKING TO THE DAYTIME HOURS TODAY...KEPT THE FORECAST DRY...AS THE DISTURBANCE IN THE AREA CONTINUES TO WEAKEN...BUT THE MAIN UPPER LEVEL LOW IS STILL WELL OF TO THE WEST. EXPECTING THAT UPWARD TREND IN SKY COVER TO CONTINUE THROUGH THE DAY...AND WHILE THERE IS LITTLE CHANGE IN THE WIND DIRECTION...ARE EXPECTING ANOTHER BREEZY DAY. MODELS ARE SHOWING SFC LOW PRESSURE TO DEVELOP OVER ERN PORTIONS OF COLORADO...AND THE RESULTING TIGHTER PRESSURE GRADIENT IS EXPECTED TO RESULT IN SPEEDS CLIMBING INTO THE 15 TO 25 MPH RANGE. BUMPED UP HIGHS A TOUCH FOR TODAY...NOT AS HIGH AS THE RAP SUGGESTS...BUT CLOSE TO THE MET/MAV...WHICH GIVES MID 60S FOR MOST OF THE CWA. PRECIPITATION CHANCES RETURN TO THE FORECAST FOR THIS EVENING AND OVERNIGHT...BUT CONFIDENCE REMAINS ON THE LOWER SIDE WITH HOW THINGS WILL EVOLVE...AS THERE CONTINUES TO BE SOME PRETTY NOTABLE DIFFERENCES BETWEEN MODELS. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE HIGH PLAINS LATER THIS AFTERNOON...PUSHING FURTHER EAST THIS EVENING/OVERNIGHT AS A PIECE OF UPPER LEVEL SHORTWAVE ENERGY MOVES INTO THE REGION. THERE IS SOME QUESTION WITH THE OVERALL COVERAGE OF THIS ACTIVITY AS IT MOVES INTO THE AREA...AND HOW QUICKLY IT DOES SO. WHILE SOME ADJUSTMENTS WERE MADE TO TIMING/LOCATION OF POPS...NO SIGNIFICANT CHANGES WERE DONE. CONTINUE TO HAVE POPS STARTING AT 00Z...BUT SOME MODELS SUGGEST THAT IS TOO EARLY...THAT IT MAY BE CLOSER TO 03Z BEFORE WRN PORTIONS OF THE CWA ARE AFFECTED. ACTIVITY IS EXPECTED TO CONTINUE SHIFTING E/NE...BUT MODELS DIFFER WITH HOW FAR THINGS GET PRIOR TO 12Z. IT RANGES FROM OUTPUT LIKE THE 4KM/ECMWF SHOWING VERY LITTLE MAKING IT IN OR MOVING THROUGH...VS THE GFS/SREF WHICH SHOW QPF FURTHER INTO THE N/NERN AREAS. EARLY ON...THERE IS THE CHANCE FOR A FEW OF THOSE THUNDERSTORMS ACROSS FAR WRN AREAS TO BE ON THE STRONG SIDE...BUT THE 00Z RUN OF MODELS GENERALLY SHOWED MUCAPE VALUES TOPPING OUT IN THE 500-1000 J/KG RANGE. THE SPC DAY 1 OUTLOOK CLIPS WRN PORTIONS OF THE CWA WITH A MARGINAL RISK TODAY...WILL KEEP THE MENTION OF STRONG STORMS IN THE HWO. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 420 AM CDT WED APR 15 2015 THE BIG WEATHER STORY WILL CONTINUE TO REVOLVE AROUND THE INCREASINGLY LIKELY CHANCE OF APPRECIABLE RAINFALL THURSDAY THROUGH SATURDAY NIGHT. THE MOST RECENT 00Z RUNS OF THE ECMWF AND GFS SHOW QPF TOTALS OF 1 TO 3 INCHES ACROSS THE ENTIRE FORECAST AREA IN THE PERIOD BEGINNING THURSDAY AND ENDING AT 6 AM SUNDAY MORNING. GIVEN THE PROLONGED OFF AND ON AGAIN SEVERAL DAYS OF RAIN...WOULD NOT BE SURPRISED SO SEE A FEW 3 DAY RAINFALL TOTALS IN THE 4 TO 5 INCH RANGE...ALTHOUGH MOST AREAS ARE MORE LIKELY TO SEE SOMETHING CLOSER TO THE 1 TO 3 INCHES INDICATED BY THE MODELS. THE LOCALLY HIGHER TOTALS WILL BE POSSIBLE WITHIN AREAS OF STRONGER CONVECTION AS INSTABILITY WILL BE MORE THAN SUFFICIENT FOR THUNDERSTORMS ON AT LEAST THURSDAY AND FRIDAY. INSTABILITY BEGINS TO REALLY DECREASE BY SATURDAY. NORMALLY THESE KIND OF RAINS WOULD SPARK FLOODING CONCERNS. ALTHOUGH WE CAN NOT RULE OUT SOME LOCALIZED FLOODING...THE RAIN WILL COME ON AND OFF AGAIN OVER SEVERAL DAYS AND WE HAVE BEEN ABNORMALLY DRY THUS GREATLY LIMITING ANY FLOODING THREAT DESPITE THE POTENTIAL FOR HEAVY RAINFALL AMOUNTS. ALL OF THE EXPECTED PRECIPITATION IS A RESULT OF A SIGNIFICANT UPPER LEVEL STORM SYSTEM THAT WILL DIG ACROSS THE ROCKIES...BECOME CUT OFF...AND THEN SLOWLY TRACKS EAST THROUGH THE PLAINS. FORECAST MODELS ARE IN GOOD AGREEMENT THAT THIS UPPER LOW WILL TRACK VERY SLOWLY ACROSS THE PLAINS DUE TO BEING CUT OFF FROM THE NORTHERN STREAM OF THE UPPER JET. THIS WILL ALLOW PLENTY OF TIME FOR GULF MOISTURE TO STREAM NORTHWARD THROUGH THE PLAINS AND GIVE US A PROLONGED WINDOW OF PRECIPITATION CHANCES. FORECAST MODELS AND THEIR ENSEMBLES ARE COMING INTO BETTER AGREEMENT WITH THE OVERALL TRACK OF THE LARGE SCALE SYNOPTIC SYSTEM...WHICH AS STATED EARLIER IS LOOKING PRETTY WET FOR THE SOUTHERN AND CENTRAL PLAINS. THERE IS STILL PLENTY OF UNCERTAINTY IN HOW THINGS WILL EVOLVE IN THE MESOSCALE AND STORM SCALE WITH REGARD TO TIMING OF MULTIPLE CONVECTIVE LINES...AND EVEN POSSIBLE MCS ACTIVITY. THURSDAY AND FRIDAY...FORECAST MODELS VARY ON HOW MUCH INSTABILITY WE WILL HAVE TO WORK WITH...BUT THE GENERAL CONSENSUS IS THAT THERE WILL BE AT LEAST ENOUGH INSTABILITY FOR GENERAL THUNDERSTORMS THURSDAY AND FRIDAY. THE 00Z GFS ACTUALLY HAS OVER 1000 J/KG OF SBCAPE BOTH THURSDAY AND FRIDAY AFTERNOON OVER PRIMARILY OUR KANSAS COUNTIES. DEEP LAYER SHEAR VALUES SHOULD BE AROUND 30 KTS IF NOT HIGHER AND THUS A FEW THUNDERSTORMS COULD BECOME SEVERE EITHER DAY WITH THE HIGHER LIKELIHOOD OF A FEW SEVERE THUNDERSTORMS BEING ACROSS OUR KANSAS COUNTIES. FORECAST MODELS HAVE CONSISTENTLY BEEN CALLING FOR HIGHS IN THE 60S DESPITE CLOUDY SKIES AND OFF AND ON AGAIN RAIN SO WILL CONTINUE TO KEEP THESE 60S IN THE FORECAST. SATURDAY AND SUNDAY...THE UPPER SYSTEM WILL FINALLY BE EJECTING INTO THE PLAINS AT SOME POINT ON SATURDAY AND THIS IS WHEN THE FORECAST MODELS START TO DIVERGE. OVERALL MOST MODELS STILL GIVE US A GOOD CHANCE OF SHOWERS ON SATURDAY WITH ABUNDANT MOISTURE STREAMING NORTH THROUGH THE PLAINS. HOWEVER...BY SUNDAY THE UPPER LOW WILL HAVE WEAKENED AND POSSIBLY EVEN TRACKED EAST OF OUR AREA THUS THE PRECIPITATION CHANCES ARE LOWER AND MAY NEED TO BE EVEN LOWER OR TAKEN OUT ALTOGETHER DEPENDING ON HOW THINGS EVOLVE IN THE COMING DAYS. INSTABILITY IS GENERALLY WEAKER THAN THE PRECEDING DAYS AND THUS SEVERE WEATHER CURRENTLY SEEMS UNLIKELY UNLESS SOMETHING WERE TO CHANGE. HIGHS SHOULD STILL BE IN THE 60S. MONDAY AND TUESDAY...MOST AREAS SHOULD BE DRY WITH HIGHS IN THE 60S. && .AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 630 AM CDT WED APR 15 2015 PRIMARY FORECAST CONCERNS COME LATE IN THE TAF PERIOD...AS AN UPPER LEVEL DISTURBANCE BRINGS INCREASING PRECIPITATION CHANCES. LOOKING TO THE DAYTIME HOURS...CURRENTLY HAVE DRY/VFR CONDITIONS IN PLACE. SATELLITE IMAGERY SHOWS AN AREA OF LOWER LEVEL CLOUDS PUSHING N/NW INTO THE AREA...BUT UPSTREAM OBS SHOW VFR CEILINGS. SERLY WINDS WILL ONCE AGAIN BE ON THE BREEZY SIDE...WITH SPEEDS INCREASING TO 15 TO 25 MPH WITH GUSTS NEAR 30 MPH POSSIBLE. MODELS/GUIDANCE SUGGEST LOWERING CEILINGS ALONG WITH THE PRECIP...AND HAVE IFR CONDITIONS DEVELOPING. THERE IS SOME DATA THAT SUGGESTS IT COULD BE LOWER THAN THAT...BUT OVERALL CONFIDENCE IN THE CEILINGS AS WELL AS THE EVOLUTION OF PRECIP IS LOW ENOUGH TO NOT GO ANY LOWER THAN 1K FT. ALSO BECAUSE OF UNCERTAINTY...HAVE PRECIP MENTION GOING AS VCTS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADP LONG TERM...WESELY AVIATION...ADP
AREA FORECAST DISCUSSION
NWS HASTINGS NE
421 AM CDT WED APR 15 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 420 AM CDT WED APR 15 2015 QUIET CONDITIONS REMAIN IN PLACE ACROSS THE CWA THIS MORNING...WITH UPPER AIR AND SATELLITE DATA SHOWING AN UPPER LEVEL DISTURBANCE SLOWLY SLIDING NE ACROSS CENTRAL/ERN PORTIONS OF KS/NE. THIS DISTURBANCE IS GRADUALLY BECOMING MORE PHASED WITH A STRONGER UPPER LEVEL LOW PRESSURE SYSTEM...WHICH IS CURRENTLY LOCATED OVER NRN PORTIONS OF UTAH. REGIONAL RADAR SHOWS A FEW SHOWERS/SPRINKLES HAVE DEVELOPED OVER FAR SERN NEB/ERN KS...BUT THE CWA REMAINS DRY. AT THE SFC...SERLY WINDS ARE IN PLACE WITH SPEEDS IN THE 5 TO 15 MPH RANGE...SET UP BETWEEN HIGH PRESSURE OVER THE GREAT LAKES AND A TROUGH OF LOW PRESSURE DRAPED ALONG THE HIGH PLAINS. AS THIS UPPER LEVEL DISTURBANCE CONTINUES PUSHING NE EARLY THIS MORNING ALONG WITH THE SERLY LOWER LEVEL FLOW...SATELLITE IMAGERY SHOWS INCREASING CLOUD COVER MOVING NORTH AS WELL. MOST OF THE CWA IS CURRENTLY MOSTLY CLEAR...BUT SERN PORTIONS ARE SEEING MORE SKY COVER. LOOKING TO THE DAYTIME HOURS TODAY...KEPT THE FORECAST DRY...AS THE DISTURBANCE IN THE AREA CONTINUES TO WEAKEN...BUT THE MAIN UPPER LEVEL LOW IS STILL WELL OF TO THE WEST. EXPECTING THAT UPWARD TREND IN SKY COVER TO CONTINUE THROUGH THE DAY...AND WHILE THERE IS LITTLE CHANGE IN THE WIND DIRECTION...ARE EXPECTING ANOTHER BREEZY DAY. MODELS ARE SHOWING SFC LOW PRESSURE TO DEVELOP OVER ERN PORTIONS OF COLORADO...AND THE RESULTING TIGHTER PRESSURE GRADIENT IS EXPECTED TO RESULT IN SPEEDS CLIMBING INTO THE 15 TO 25 MPH RANGE. BUMPED UP HIGHS A TOUCH FOR TODAY...NOT AS HIGH AS THE RAP SUGGESTS...BUT CLOSE TO THE MET/MAV...WHICH GIVES MID 60S FOR MOST OF THE CWA. PRECIPITATION CHANCES RETURN TO THE FORECAST FOR THIS EVENING AND OVERNIGHT...BUT CONFIDENCE REMAINS ON THE LOWER SIDE WITH HOW THINGS WILL EVOLVE...AS THERE CONTINUES TO BE SOME PRETTY NOTABLE DIFFERENCES BETWEEN MODELS. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE HIGH PLAINS LATER THIS AFTERNOON...PUSHING FURTHER EAST THIS EVENING/OVERNIGHT AS A PIECE OF UPPER LEVEL SHORTWAVE ENERGY MOVES INTO THE REGION. THERE IS SOME QUESTION WITH THE OVERALL COVERAGE OF THIS ACTIVITY AS IT MOVES INTO THE AREA...AND HOW QUICKLY IT DOES SO. WHILE SOME ADJUSTMENTS WERE MADE TO TIMING/LOCATION OF POPS...NO SIGNIFICANT CHANGES WERE DONE. CONTINUE TO HAVE POPS STARTING AT 00Z...BUT SOME MODELS SUGGEST THAT IS TOO EARLY...THAT IT MAY BE CLOSER TO 03Z BEFORE WRN PORTIONS OF THE CWA ARE AFFECTED. ACTIVITY IS EXPECTED TO CONTINUE SHIFTING E/NE...BUT MODELS DIFFER WITH HOW FAR THINGS GET PRIOR TO 12Z. IT RANGES FROM OUTPUT LIKE THE 4KM/ECMWF SHOWING VERY LITTLE MAKING IT IN OR MOVING THROUGH...VS THE GFS/SREF WHICH SHOW QPF FURTHER INTO THE N/NERN AREAS. EARLY ON...THERE IS THE CHANCE FOR A FEW OF THOSE THUNDERSTORMS ACROSS FAR WRN AREAS TO BE ON THE STRONG SIDE...BUT THE 00Z RUN OF MODELS GENERALLY SHOWED MUCAPE VALUES TOPPING OUT IN THE 500-1000 J/KG RANGE. THE SPC DAY 1 OUTLOOK CLIPS WRN PORTIONS OF THE CWA WITH A MARGINAL RISK TODAY...WILL KEEP THE MENTION OF STRONG STORMS IN THE HWO. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 420 AM CDT WED APR 15 2015 THE BIG WEATHER STORY WILL CONTINUE TO REVOLVE AROUND THE INCREASINGLY LIKELY CHANCE OF APPRECIABLE RAINFALL THURSDAY THROUGH SATURDAY NIGHT. THE MOST RECENT 00Z RUNS OF THE ECMWF AND GFS SHOW QPF TOTALS OF 1 TO 3 INCHES ACROSS THE ENTIRE FORECAST AREA IN THE PERIOD BEGINNING THURSDAY AND ENDING AT 6 AM SUNDAY MORNING. GIVEN THE PROLONGED OFF AND ON AGAIN SEVERAL DAYS OF RAIN...WOULD NOT BE SURPRISED SO SEE A FEW 3 DAY RAINFALL TOTALS IN THE 4 TO 5 INCH RANGE...ALTHOUGH MOST AREAS ARE MORE LIKELY TO SEE SOMETHING CLOSER TO THE 1 TO 3 INCHES INDICATED BY THE MODELS. THE LOCALLY HIGHER TOTALS WILL BE POSSIBLE WITHIN AREAS OF STRONGER CONVECTION AS INSTABILITY WILL BE MORE THAN SUFFICIENT FOR THUNDERSTORMS ON AT LEAST THURSDAY AND FRIDAY. INSTABILITY BEGINS TO REALLY DECREASE BY SATURDAY. NORMALLY THESE KIND OF RAINS WOULD SPARK FLOODING CONCERNS. ALTHOUGH WE CAN NOT RULE OUT SOME LOCALIZED FLOODING...THE RAIN WILL COME ON AND OFF AGAIN OVER SEVERAL DAYS AND WE HAVE BEEN ABNORMALLY DRY THUS GREATLY LIMITING ANY FLOODING THREAT DESPITE THE POTENTIAL FOR HEAVY RAINFALL AMOUNTS. ALL OF THE EXPECTED PRECIPITATION IS A RESULT OF A SIGNIFICANT UPPER LEVEL STORM SYSTEM THAT WILL DIG ACROSS THE ROCKIES...BECOME CUT OFF...AND THEN SLOWLY TRACKS EAST THROUGH THE PLAINS. FORECAST MODELS ARE IN GOOD AGREEMENT THAT THIS UPPER LOW WILL TRACK VERY SLOWLY ACROSS THE PLAINS DUE TO BEING CUT OFF FROM THE NORTHERN STREAM OF THE UPPER JET. THIS WILL ALLOW PLENTY OF TIME FOR GULF MOISTURE TO STREAM NORTHWARD THROUGH THE PLAINS AND GIVE US A PROLONGED WINDOW OF PRECIPITATION CHANCES. FORECAST MODELS AND THEIR ENSEMBLES ARE COMING INTO BETTER AGREEMENT WITH THE OVERALL TRACK OF THE LARGE SCALE SYNOPTIC SYSTEM...WHICH AS STATED EARLIER IS LOOKING PRETTY WET FOR THE SOUTHERN AND CENTRAL PLAINS. THERE IS STILL PLENTY OF UNCERTAINTY IN HOW THINGS WILL EVOLVE IN THE MESOSCALE AND STORM SCALE WITH REGARD TO TIMING OF MULTIPLE CONVECTIVE LINES...AND EVEN POSSIBLE MCS ACTIVITY. THURSDAY AND FRIDAY...FORECAST MODELS VARY ON HOW MUCH INSTABILITY WE WILL HAVE TO WORK WITH...BUT THE GENERAL CONSENSUS IS THAT THERE WILL BE AT LEAST ENOUGH INSTABILITY FOR GENERAL THUNDERSTORMS THURSDAY AND FRIDAY. THE 00Z GFS ACTUALLY HAS OVER 1000 J/KG OF SBCAPE BOTH THURSDAY AND FRIDAY AFTERNOON OVER PRIMARILY OUR KANSAS COUNTIES. DEEP LAYER SHEAR VALUES SHOULD BE AROUND 30 KTS IF NOT HIGHER AND THUS A FEW THUNDERSTORMS COULD BECOME SEVERE EITHER DAY WITH THE HIGHER LIKELIHOOD OF A FEW SEVERE THUNDERSTORMS BEING ACROSS OUR KANSAS COUNTIES. FORECAST MODELS HAVE CONSISTENTLY BEEN CALLING FOR HIGHS IN THE 60S DESPITE CLOUDY SKIES AND OFF AND ON AGAIN RAIN SO WILL CONTINUE TO KEEP THESE 60S IN THE FORECAST. SATURDAY AND SUNDAY...THE UPPER SYSTEM WILL FINALLY BE EJECTING INTO THE PLAINS AT SOME POINT ON SATURDAY AND THIS IS WHEN THE FORECAST MODELS START TO DIVERGE. OVERALL MOST MODELS STILL GIVE US A GOOD CHANCE OF SHOWERS ON SATURDAY WITH ABUNDANT MOISTURE STREAMING NORTH THROUGH THE PLAINS. HOWEVER...BY SUNDAY THE UPPER LOW WILL HAVE WEAKENED AND POSSIBLY EVEN TRACKED EAST OF OUR AREA THUS THE PRECIPITATION CHANCES ARE LOWER AND MAY NEED TO BE EVEN LOWER OR TAKEN OUT ALTOGETHER DEPENDING ON HOW THINGS EVOLVE IN THE COMING DAYS. INSTABILITY IS GENERALLY WEAKER THAN THE PRECEDING DAYS AND THUS SEVERE WEATHER CURRENTLY SEEMS UNLIKELY UNLESS SOMETHING WERE TO CHANGE. HIGHS SHOULD STILL BE IN THE 60S. MONDAY AND TUESDAY...MOST AREAS SHOULD BE DRY WITH HIGHS IN THE 60S. && .AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1237 AM CDT WED APR 15 2015 OVERALL CONFIDENCE IN THIS TAF IS NOT THE HIGHEST...ESPECIALLY AS WE GET FURTHER INTO TODAY/THIS EVENING. AT THIS TIME...KEPT THINGS VFR. SHOULD SEE INCREASING CLOUD COVER SLIDING IN FROM THE SOUTHEAST WITH TIME...BUT LOOKING AT OBS UPSTREAMS CEILINGS ARE ABOVE 3K FT. LATER IN THE TAF PERIOD /THIS EVENING/...THERE LOOKS TO BE BETTER POTENTIAL FOR MVFR CEILINGS...AND INSERTED A SCT MENTION FOR NOW AND WILL SEE HOW UPCOMING MODEL RUNS TREND. WITH THE BETTER PRECIPITATION CHANCES LOOKING TO HOLD OFF UNTIL THE VERY END OR JUST BEYOND THIS TAF PERIOD...KEPT MENTION OUT BUT ONE MAY BE NEEDED FOR THE 12Z TAF FORECAST. WINDS THROUGH THIS PERIOD REMAIN SOUTHEASTERLY...AND ARE EXPECTED TO BE GUSTY ONCE AGAIN DURING THE DAYTIME HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADP LONG TERM...WESELY AVIATION...ADP
AREA FORECAST DISCUSSION...COR
NWS WILMINGTON NC
331 PM EDT WED APR 15 2015 .SYNOPSIS... HIGH PRESSURE WEDGING DOWN ACROSS THE CAROLINAS THROUGH TONIGHT WILL KEEP CLOUDY COOL AND DAMP WEATHER OVERNIGHT. A WAVE OF LOW PRESSURE WILL DEVELOP ALONG THE FRONT TO THE SOUTH TONIGHT AND WILL TRACK NORTH JUST OFF THE CAROLINA COAST THROUGH FRIDAY. THE LOW WILL THEN MOVE OFF TO THE EAST...LEAVING HIGH PRESSURE OVER THE CAROLINAS BY THE WEEKEND. A WARM FRONT WILL MOVE NORTH THROUGH THE CAROLINAS ON SUNDAY WITH A COLD FRONT TO FOLLOW MONDAY NIGHT INTO TUESDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 300 PM WEDNESDAY...HIGH PRESSURE WEDGING IN ACROSS THE CAROLINAS THROUGH TONIGHT WILL KEEP CLOUDY COOL AND DAMP WEATHER OVERNIGHT. THE COOLER AIR BEHIND FRONT IS BEING OVERRUN BY WARMER MOISTER AIR ALOFT LEAVING A STRATUS DECK AND LIGHT INTERMITTENT DRIZZLE OR LIGHT PATCHY RAIN OVER MOST OF FORECAST AREA THIS AFTERNOON. SOME DRYING NEAR THE SURFACE HAS LIFTED THE STRATUS DECK IN SPOTS BUT SOUNDINGS AND MOISTURE PROFILES SHOW COLUMN BECOMING SATURATED THIS EVENING. HRRR SHOWS LARGE AREA OF PCP TO THE WEST ENTERING OUR WESTERN CWA BY 21Z OR 5PM BUT IT DIMINISHES IN COVERAGE AS IT MOVES EAST TOWARD THE COAST. FOR NOW WILL CONTINUE WITH FORECAST AS IS...LEAVING HIGHER POPS BUT LOW END QPF. ANY CONVECTION ALONG FRONT DRAPED FROM SOUTH CAROLINA...JUST SW OF AREA TO THE NE INTO THE COASTAL WATERS WILL MOVE RAPIDLY OFF TO THE NORTHEAST AS WINDS ALOFT REMAIN OUT OF THE SW ON THE BACK SIDE OF RIDGE. THEREFORE COULD SEE AN ISOLATED THUNDERSTORM MAKE IT NEAR OR INTO SOUTHERN PORTION OF CWA...MAINLY WILLIAMSBURG COUNTY BUT AS FRONT MOVES SLOWLY SOUTH THROUGH THIS EVE EXPECT CONVECTION TO SHIFT SOUTH AND DIE DOWN AS HEATING OF THE DAY CUTS OFF. THIS HIGH PRESSURE WILL BUILD AND WEDGE DOWN THROUGH THE CAROLINAS THROUGH TONIGHT AS WAVE OF LOW PRESSURE DEVELOPS ALONG LINGERING FRONT TO THE SOUTHEAST IN THE COASTAL WATERS OFF THE GA/SC COAST. A TROUGH WILL EXTEND UP FROM THIS LOW PRESSURE TIGHTENING THE GRADIENT FLOW OUT OF THE NORTHEAST THROUGH TONIGHT ENHANCING THE SHALLOW COOL NE WINDS. EXPECT INCREASING ISENTROPIC LIFT TO PRODUCE BETTER CHC OF RAIN BY THIS EVENING INTO TONIGHT WITH COLUMN BEING SATURATED UP THROUGH H50. OVERALL EXPECT CLOUDY SKIES AND PERIODS OF RAIN THROUGH AT LEAST THIS EVE BUT NOT CONFIDENT AS TO THE INTENSITY. MODELS SHOW PERTURBATION IN THE MID TO UPPER LEVEL FLOW MOVING THROUGH THIS EVENING AND THIS MAY ACT TO ENHANCE LIFT AND PRODUCE SOME PERIODS OF MORE MODERATE RAIN. TEMPS WILL HOLD IN THE MID 60S THROUGH THIS AFTERNOON BEHIND COLD FRONT WITH EXTENSIVE CLOUD COVER AND CAA AS 850 TEMPS DROP DOWN FROM 14C THIS MORNING TO 9C BY THURS MORNING. TEMPS WILL DROP INTO THE UPPER 40S TO MID 50S TONIGHT IN CONTINUED CAA. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... AS OF 300 PM WEDNESDAY...THE FORECAST HAS BECOME NO LESS COMPLICATED AND IN FACT...IN SOME RESPECTS...MODELS HAVE DIVERGED EVEN FURTHER IN THE LAST 24 HOURS. THE GFS SOLUTION LOOKS VERY DIFFERENT FROM PREVIOUS RUNS. THE NAM SOLUTION LOOKS SIMILAR TO PREVIOUS THINKING...BUT THE PROGRESSION OF OFFSHORE LOW PRESSURE IS SLOWER AND FURTHER EASTWARD THAN 24 HOURS AGO AND CERTAINLY MUCH STRONGER. THE CANADIAN IS CONSIDERABLY SLOWER AND WEAKER THAN THE NAM AS IS THE EUROPEAN...BUT BOTH DO CLOSE OFF LOW PRESSURE ALONG THE COAST OF SOUTH CAROLINA. SLOWER SEEMS REASONABLE GIVEN THE STRENGTH OF HIGH PRESSURE TO THE NORTH AND RESULTING WEDGE...THUS THE BEST WE CAN DO AT THIS POINT IS TO GO ALONG WITH PERSISTENCE...BUT SLOW PROGRESSION. WILL INCLUDE HIGHEST POPS THU ALONG THE COAST AND UP TO CATEGORICAL THU MORNING ALONG THE CAPE FEAR COAST DUE TO STRENGTH OF ISENTROPIC LIFT COUPLED WITH THE LIFT ASSOCIATED WITH LOW PRESSURE/TROUGH. WILL THEN TREND POPS LOWER THU AFTERNOON AND NIGHT FROM SW TO NE WITH A LINGERING RISK ALONG THE CAPE FEAR COAST FRI MORNING. GIVEN PROXIMITY OF COASTAL TROUGH AND ELEVATED INSTABILITY...WILL INCLUDE MENTION OF THUNDER FOR PORTIONS OF THE FORECAST AREA. THE MOISTURE PROFILES DRY OUT CONSIDERABLY AS A RIDGE OF HIGH PRESSURE ALOFT BUILDS TO THE COAST FROM THE WEST TOWARD THE END OF THE PERIOD. WILL FINALLY DROP POPS BELOW THRESHOLD FRI AFTERNOON AND NIGHT...EVEN ALONG THE SEABREEZE BOUNDARY. BELOW NORMAL HIGH TEMPS ARE EXPECTED AGAIN ON THU AS WEDGE KEEPS LOW- LEVEL MOISTURE TRAPPED BENEATH INVERSION. HIGHS WILL ONLY BE IN THE LOWER TO MID 60S. DEVELOPING SUNSHINE ON FRI SHOULD ALLOW TEMPS TO RETURN TO MORE SEASONABLE LEVELS...LOW AND MID 70S. LOWS THIS PERIOD WILL BE MAINLY IN THE 50S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 300 PM WEDNESDAY...GUIDANCE HAS SHIFTED PRETTY DRAMATICALLY FROM JUST YESTERDAY...LEADING TO ENHANCED UNCERTAINTY DURING THE EXTENDED. LARGE CLOSED LOW ACROSS THE SOUTHWEST WILL ONLY VERY SLOWLY FILL AND EJECT TO THE NORTHEAST THROUGH THE WEEKEND...PHASING WITH A DEEPENING NORTHERN STREAM CUTOFF LOW ACROSS THE GREAT LAKES LATE MONDAY. THIS FEATURE WILL THEN AMPLIFY AND STALL ACROSS THE GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK...PRODUCING 500MB HEIGHTS OF -2 TO -3 SD`S BELOW CLIMO ACROSS THE NORTHEAST AND INTO THE MID-ATLANTIC. INITIALLY THE EXTENDED WILL BE WARM AND PLEASANT. SATURDAY IS SHAPING UP TO BE A GORGEOUS DAY LOCALLY...WITH HIGHS ABOVE CLIMO AND A LOT OF SUNSHINE. MOISTURE RETURNS SUNDAY IN A PRE-FRONTAL AIR MASS WHICH WILL CONTINUE INTO MONDAY AHEAD OF A COLD FRONT. SUNDAY AND MONDAY WILL BOTH FEATURE ABOVE CLIMO TEMPS...BUT WITH INCREASING RAIN CHANCES AHEAD OF THE COLD FRONT. ATTM THE FRONT DOES NOT LOOK TO BE STRONGLY FORCED SO WIDESPREAD CONVECTION IS NOT ANTICIPATED MONDAY EVENING WITH THE FROPA. COOLER HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR TUE/WED OF NEXT WEEK WITH TEMPS RETURNING TO SEASONABLE LEVELS. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 18Z...CONVECTION MAKING HEADWAY NORTHWARD AND COULD AFFECT THE MYRTLES FOR THE NEXT HOUR OR SO WITH LOWER VISIBILITIES IN THE HEAVIER SHOWERS. WEDGE FIRMLY IN PLACE WITH A STRONG INVERSION JUST OFF THE DECK. CEILINGS HAVE LIFTED IN PLACES TO MVFR...BUT EXPECT ALL TERMINALS TO SEE IFR CEILINGS AGAIN THIS EVENING. OVERNIGHT...NOT MUCH CHANGE HOWEVER THE COASTAL TERMINALS WILL SEE GUSTY WINDS AS THE GRADIENT TIGHTENS WITH THE CYCLOGENESIS. THURSDAY...CONTINUED IFR CONDITIONS WITH EAST NORTHEAST WINDS AND INTERMITTENT LIGHT TO MODERATE RAIN. EXTENDED OUTLOOK...PREDOMINATELY IFR CONDITIONS ARE EXPECTED INTO EARLY FRIDAY MORNING WITH THE WEDGE. IMPROVING CONDITIONS DURING THE DAY FRI. DETERIORATING CONDITIONS AGAIN SATURDAY NIGHT THROUGH SUNDAY WITH A SLOW MOVING FRONT. SLIGHT CHANCE FOR SHOWERS MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM WEDNESDAY...NE WINDS WILL INCREASE THROUGH THIS AFTERNOON INTO TONIGHT AS PINCHED GRADIENT DEVELOPS BETWEEN WEDGE OF HIGH PRESSURE BUILDING DOWN INTO THE CAROLINAS AND TROUGH OF LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST. OVERALL EXPECT INCREASING WINDS AND SEAS THROUGH THIS EVENING INTO THE OVERNIGHT HOURS. A SMALL CRAFT ADVISORY IS EFFECT STARTING THIS EVENING IN AS NE WINDS OF 20 TO 25 KTS AND 4 TO 7 FT SEAS DEVELOP INTO THE OVERNIGHT HOURS. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 PM WEDNESDAY...ONGOING SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED AT THE BEGINNING OF THE PERIOD AS LOW PRESSURE MOVES UP THE SOUTHEAST COAST. THE PRESSURE GRADIENT BETWEEN DEVELOPING LOW PRESSURE AND THE STRONG HIGH TO THE NORTH WILL ALLOW A TIGHT PRESSURE GRADIENT TO PERSIST INTO THU AND THIS IS WHEN WE EXPECT THE STRONGEST WINDS AND HIGHEST SEAS...UP TO 20 TO 30 KT...HIGHEST NORTHERN WATERS AND SEAS UP TO 5 TO 8 FT THROUGHOUT. AS THE PRESSURE GRADIENT SLACKENS AND LOW PRESSURE MOVES TO OUR N...WINDS AND SEAS WILL SUBSIDE THU NIGHT AND FRI WITH THIS TREND PERSISTING INTO FRI NIGHT. ENE WINDS THU WILL BACK TO NE THU NIGHT WITH NNE TO NE WINDS THEN PERSISTING THROUGH THE END OF THE PERIOD. LONG TERM /SATURDAY THROUGH MONDAY/... AS OF 300 PM WEDNESDAY...HIGH PRESSURE WILL BUILD DOWN THE COAST AND THEN MOVE OFFSHORE SATURDAY...CREATING A WEAK PRESSURE GRADIENT AND WINDS SHIFTING FROM NE EARLY...TO E/SE LATE. WINDS SPEEDS THEN STEADILY INCREASE SUNDAY AS THE GRADIENT STARTS TO PINCH AHEAD OF AN APPROACHING COLD FRONT...BECOMING S/SW AT AROUND 15 KTS MOST OF SUNDAY...AND THEN SW AT 15-20 KTS ON MONDAY DIRECTLY AHEAD OF THE FROPA. COLD FRONT WILL CROSS THE WATERS AT THE VERY END OF THE PERIOD WITH A WIND SHIFT TO THE NW AT 10-15 KTS. ALTHOUGH A WEAK SE GROUND SWELL WILL BE PRESENT IN THE SPECTRUM DURING THE EXTENDED...MUCH OF THE WAVE AMPLITUDE WILL BE FORMED VIA WIND WAVES...AND SEAS WILL BE 2-3 FT SATURDAY...BUILDING TO 3-5 FT SUNDAY AND MONDAY AHEAD OF THE COLD FRONT. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 2 AM EDT FRIDAY FOR AMZ250-252-254-256. && $$ NEAR TERM...RGZ SHORT TERM...RJD LONG TERM...JDW AVIATION...RGZ/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
309 PM EDT WED APR 15 2015 .SYNOPSIS... HIGH PRESSURE WEDGING DOWN ACROSS THE CAROLINAS THROUGH TONIGHT WILL KEEP CLOUDY COOL AND DAMP WEATHER OVERNIGHT. A WAVE OF LOW PRESSURE WILL DEVELOP ALONG THE FRONT TO THE SOUTH TONIGHT AND WILL TRACK NORTH JUST OFF THE CAROLINA COAST THROUGH THURSDAY. THE LOW WILL MOVE OFF TO THE EAST THROUGH FRIDAY LEAVING HIGH PRESSURE OVER THE CAROLINAS THROUGH SATURDAY. A WARM FRONT WILL MOVE MOVE NORTH THROUGH THE CAROLINAS ON SUNDAY WITH A COLD FRONT TO FOLLOW MONDAY NIGHT INTO TUESDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 230 PM WEDNESDAY...HIGH PRESSURE WEDGING IN ACROSS THE CAROLINAS THROUGH TONIGHT WILL KEEP CLOUDY COOL AND DAMP WEATHER OVERNIGHT. THE COOLER AIR BEHIND FRONT IS BEING OVERRUN BY WARMER MOISTER AIR ALOFT LEAVING A STRATUS DECK AND LIGHT INTERMITTENT DRIZZLE OR LIGHT PATCHY RAIN OVER MOST OF FORECAST AREA THIS AFTERNOON. SOME DRYING NEAR THE SURFACE HAS LIFTED THE STRATUS DECK IN SPOTS BUT SOUNDINGS AND MOISTURE PROFILES SHOW COLUMN BECOMING SATURATED THIS EVENING. HRRR SHOWS LARGE AREA OF PCP TO THE WEST ENTERING OUR WESTERN CWA BY 21Z OR 5PM BUT IT DIMINISHES IN COVERAGE AS IT MOVES EAST TOWARD THE COAST. FOR NOW WILL CONTINUE WITH FORECAST AS IS...LEAVING HIGHER POPS BUT LOW END QPF. ANY CONVECTION ALONG FRONT DRAPED FROM SOUTH CAROLINA...JUST SW OF AREA TO THE NE INTO THE COASTAL WATERS WILL MOVE RAPIDLY OFF TO THE NORTHEAST AS WINDS ALOFT REMAIN OUT OF THE SW ON THE BACK SIDE OF RIDGE. THEREFORE COULD SEE AN ISOLATED THUNDERSTORM MAKE IT NEAR OR INTO SOUTHERN PORTION OF CWA...MAINLY WILLIAMSBURG COUNTY BUT AS FRONT MOVES SLOWLY SOUTH THROUGH THIS EVE EXPECT CONVECTION TO SHIFT SOUTH AND DIE DOWN AS HEATING OF THE DAY CUTS OFF. THIS HIGH PRESSURE WILL BUILD AND WEDGE DOWN THROUGH THE CAROLINAS THROUGH TONIGHT AS WAVE OF LOW PRESSURE DEVELOPS ALONG LINGERING FRONT TO THE SOUTHEAST IN THE COASTAL WATERS OFF THE GA/SC COAST. A TROUGH WILL EXTEND UP FROM THIS LOW PRESSURE TIGHTENING THE GRADIENT FLOW OUT OF THE NORTHEAST THROUGH TONIGHT ENHANCING THE SHALLOW COOL NE WINDS. EXPECT INCREASING ISENTROPIC LIFT TO PRODUCE BETTER CHC OF RAIN BY THIS EVENING INTO TONIGHT WITH COLUMN BEING SATURATED UP THROUGH H50. OVERALL EXPECT CLOUDY SKIES AND PERIODS OF RAIN THROUGH AT LEAST THIS EVE BUT NOT CONFIDENT AS TO THE INTENSITY. MODELS SHOW PERTURBATION IN THE MID TO UPPER LEVEL FLOW MOVING THROUGH THIS EVENING AND THIS MAY ACT TO ENHANCE LIFT AND PRODUCE SOME PERIODS OF MORE MODERATE RAIN. TEMPS WILL HOLD IN THE MID 60S THROUGH THIS AFTERNOON BEHIND COLD FRONT WITH EXTENSIVE CLOUD COVER AND CAA AS 850 TEMPS DROP DOWN FROM 14C THIS MORNING TO 9C BY THURS MORNING. TEMPS WILL DROP INTO THE UPPER 40S TO MID 50S TONIGHT IN CONTINUED CAA. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 AM WEDNESDAY...SURFACE HIGH OVER NEW ENGLAND WILL WEDGE DOWN THE COAST THU MAINTAINING COOL AND CLOUDY CONDITIONS. LOW LEVEL NORTHEAST FLOW WILL KEEP HIGHS BELOW CLIMO WHILE MID LEVEL SOUTHWEST FLOW WILL RESULT IN STEADY ISENTROPIC LIFT. ON AND OFF LIGHT RAIN IS EXPECTED THU BUT WITH LITTLE IN THE WAY OF MID LEVEL SUPPORT HEAVY RAIN OR CONVECTION DOES NOT APPEAR TO BE MUCH OF AN ISSUE. SO WHILE POP WILL BE HIGH OVERALL QPF IS LIKELY TO BE ON THE LOW SIDE. SURFACE HIGH SHIFTS OFF THE NEW ENGLAND COAST THU NIGHT INTO FRI...WEAKENING THE WEDGE. THIS COMBINED WITH BUILDING MID LEVEL HEIGHTS/THICKNESS LEADS TO A WARMING TREND. APPEARS SUBSIDENCE UNDER THE WEAK 5H RIDGE MAY DRY OUT MID LEVEL ENOUGH TO PREVENT ANY WIDESPREAD CONVECTION BUT NOT READY TO REMOVE POP FROM THE FORECAST GIVEN ABUNDANT LOW LEVEL MOISTURE AND DIURNAL INSTABILITY. SKIES FOR MUCH OF FRI SHOULD BE CLOUDY BUT THERE MAY BE BREAKS OF SUN LATE...ESPECIALLY TO THE WEST. HIGHS END UP NEAR TO ABOVE CLIMO DESPITE THE CLOUD COVER AND LOW LEVEL NORTHERLY FLOW...MAINLY DUE TO MID AND LOW LEVEL SUBSIDENCE AND NORTHERLY FLOW WITH MORE OF A WESTERLY COMPONENT. LOWS THU AND FRI NIGHTS WILL BE ABOVE TO WELL ABOVE CLIMO. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 AM WEDNESDAY...WEATHER REMAINS UNSETTLED THIS WEEKEND AS DEEP SOUTHWEST FLOW CONTINUES PUMPING MOISTURE OVER THE SOUTHEAST. IT DOES APPEAR A BRIEF REPRISE IS IN STORE FOR MOST OF SAT AS SUBSIDENCE AT THE TOP OF WEAK 5H RIDGE MAY PREVENT ANY WIDESPREAD SIGNIFICANT PRECIP. HOWEVER SAT NIGHT INTO SUN THE MID LEVEL RIDGE SHIFTS EAST AND 5H CUTOFF OVER THE SOUTHWEST STARTS SLOWLY LIFTING NORTHEAST...OPENING UP AS IT DOES SO. A SERIES OF SHORTWAVES WILL PRECEDE THE 5H TROUGHS PASSAGE...MOVING OVER THE SOUTHEAST SAT AND SUN. THESE FEATURES WILL HELP ENHANCE CONVECTION DEVELOPING IN AN INCREASINGLY UNSTABLE ENVIRONMENT. THE REMNANTS OF THE 5H CUTOFF IS LIFTED EAST-NORTHEAST BY LONGWAVE 5H TROUGH MOVING ACROSS SOUTHERN CANADA. AS A RESULT A WARM FRONT IS LIFTED ACROSS THE SOUTHEAST EARLY MON WITH A COLD FRONT SLATED TO CROSS THE AREA MON EVENING/NIGHT. IT CURRENTLY APPEARS THE WARM FRONT IS WHERE MOST OF THE ACTIVITY WILL BE FOUND...GIVEN THE ABUNDANT DEEP MOISTURE AND INSTABILITY. DEEP DRY AIR MOVES IN AHEAD OF THE COLD FRONT WHICH WILL LIMIT CONVECTION IN THE WARM SECTOR. SHORTWAVE HELPING TO PUSH THE FRONT ACROSS THE AREA MAY HAVE ENOUGH MOISTURE TO GENERATE SOME CONVECTION SO WILL MAINTAIN INHERITED CHC POP FOR NOW THOUGH CONFIDENCE IS LOW. BROAD MID LEVEL TROUGH LINGERS OVER THE EASTERN CONUS TUE WITH LITTLE IN THE WAY OF MOISTURE AND A LACK OF ANY FEATURES. LIMITED COLD ADVECTION FOLLOWING THE FRONT COMBINED WITH WEST TO NORTHWEST FLOW AND LATE APRIL SUN WILL KEEP TEMPS ABOVE CLIMO TUE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 18Z...CONVECTION MAKING HEADWAY NORTHWARD AND COULD AFFECT THE MYRTLES FOR THE NEXT HOUR OR SO WITH LOWER VISIBILITIES IN THE HEAVIER SHOWERS. WEDGE FIRMLY IN PLACE WITH A STRONG INVERSION JUST OFF THE DECK. CEILINGS HAVE LIFTED IN PLACES TO MVFR...BUT EXPECT ALL TERMINALS TO SEE IFR CEILINGS AGAIN THIS EVENING. OVERNIGHT...NOT MUCH CHANGE HOWEVER THE COASTAL TERMINALS WILL SEE GUSTY WINDS AS THE GRADIENT TIGHTENS WITH THE CYCLOGENESIS. THURSDAY...CONTINUED IFR CONDITIONS WITH EAST NORTHEAST WINDS AND INTERMITTENT LIGHT TO MODERATE RAIN. EXTENDED OUTLOOK...PREDOMINATELY IFR CONDITIONS ARE EXPECTED INTO EARLY FRIDAY MORNING WITH THE WEDGE. IMPROVING CONDITIONS DURING THE DAY FRI. DETERIORATING CONDITIONS AGAIN SATURDAY NIGHT THROUGH SUNDAY WITH A SLOW MOVING FRONT. SLIGHT CHANCE FOR SHOWERS MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 230 PM WEDNESDAY...NE WINDS WILL INCREASE THROUGH THIS AFTERNOON INTO TONIGHT AS PINCHED GRADIENT DEVELOPS BETWEEN WEDGE OF HIGH PRESSURE BUILDING DOWN INTO THE CAROLINAS AND TROUGH OF LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST. OVERALL EXPECT INCREASING WINDS AND SEAS THROUGH THIS EVENING INTO THE OVERNIGHT HOURS. A SMALL CRAFT ADVISORY IS EFFECT STARTING THIS EVENING IN AS NE WINDS OF 20 TO 25 KTS AND 4 TO 7 FT SEAS DEVELOP INTO THE OVERNIGHT HOURS. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 AM WEDNESDAY...PINCHED GRADIENT OVER THE WATERS THU AND THU NIGHT AS HIGH RIDGES DOWN THE COAST WILL MAINTAIN STRONG NORTHEAST FLOW. EXPECT A SOLID 20 KT WITH POTENTIAL FOR 20 TO 25 KT AT TIMES. ALTHOUGH WIND SPEEDS MAY END UP SHORT OF SCA THRESHOLDS SEAS WILL EXCEED 6 FT SO SCA HAS BEEN CONTINUED FROM WED NIGHT TO THU EVENING. FURTHER EXTENSION MAY BE REQUIRED WITH LATER UPDATES. GRADIENT STARTS TO RELAX FRI AS WEDGE BREAKS DOWN AND WEAK WAVE FORMING ON COASTAL TROUGH LIFTS NORTHEAST. WINDS WILL REMAIN NORTHERLY ON FRI WITH SPEEDS SLOWLY DECREASING. LATER IN THE DAY FLOW WILL BECOME A LITTLE MORE OFFSHORE. SEAS ALSO START TO TREND DOWN ON FRI...FALLING FROM 3 TO 6 FT IN THE MORNING TO 2 TO 4 FT BY EVENING. LIGHT NORTHERLY FLOW FRI NIGHT WILL BECOME VARIABLE AS THE PERIOD ENDS. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 3 AM WEDNESDAY...LIGHT AND VARIABLE WINDS AT THE START OF THE PERIOD WILL BECOME SOUTHERLY DURING SAT BUT WITH VERY LITTLE INCREASE IN SPEED. FLOW WILL REMAIN SOUTH TO SOUTHEAST THROUGH THE PERIOD AS HIGH PRESSURE TO THE NORTH SLIDES OFF THE COAST. ALTHOUGH WIND SPEEDS WILL REMAIN UNDER 10 KT FOR MUCH OF THE PERIOD SEAS WILL EXPERIENCE A GRADUAL INCREASING TREND...ESPECIALLY ON SUN. SEAS START OUT 2 TO 3 FT WITH SOME ISOLATED 4 FT POSSIBLE LATER SAT. BY SUN MORNING 2 TO 4 FT IS EXPECTED WITH POTENTIAL FOR 3 TO 5 FT BY THE END OF THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 2 AM EDT FRIDAY FOR AMZ250-252-254-256. && $$ NEAR TERM...RGZ SHORT TERM...III LONG TERM...III AVIATION...RAN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
210 PM EDT WED APR 15 2015 .SYNOPSIS...COOL HIGH PRESSURE WILL BUILD SOUTH INTO CENTRAL NC TODAY AND REMAIN OVER THE REGION THROUGH THURSDAY. AN AREA OF LOW PRESSURE WILL DRIFT NORTHEAST OFF OF THE SOUTHEAST U.S. COAST LATE THURSDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1100 AM WEDNESDAY... A COMBINATION OF UPPER LEVEL DIVERGENCE...AN APPROACHING 850 MB TROUGH...AND THE SOUTHWARD ADVANCEMENT OF A SURFACE COLD FRONT HAS LEAD TO A MIX OF FORCING MECHANISMS THAT HAVE CONTRIBUTED TO WIDESPREAD PRECIPITATION FALLING ACROSS AT LEAST THE WESTERN HALF OF THE STATE. FURTHER TO THE NORTH AND EAST...DEWPOINTS ARE CONSIDERABLY LOWER AS A SECONDARY SURGE OF DRIER AIR IS MOVING IN FROM THE NORTH. COUPLE THAT WITH HIGHER CLOUD BASES AND PRECIPITATION TRYING TO MOVE EASTWARD IS RUNNING INTO A LOT OF RESISTANCE EAST OF ROUTE 1. RELATIVE HUMIDITY CROSS SECTIONS FROM THE HRRR HAVE SHOWN THE TEMPORARY LIFTING OF THE CLOUD BASES BUT ALSO DEPICT A SECONDARY SURGE OF MOISTURE THAT LOWERS CLOUD BASES AND INCREASES CHANCES FOR PRECIPITATION ONCE AGAIN THIS AFTERNOON. A LOOK AT THE CONVECTING ALLOWING MODELS CONFIRMS THIS AS THEY HOLD OFF PRECIPITATION THROUGH 18Z BUT THEN BRING WIDESPREAD RAIN TO THE ENTIRE AREA LATER INTO THE AFTERNOON AND EVENING. HIGH TEMPERATURES WILL BE TRICKY TODAY BUT EXPECT LOWEST TEMPS IN THE NORTHWEST PIEDMONT WHERE HIGHS HAVE MOST LIKELY ALREADY BEEN ACHIEVED. TO THE EAST...THERE WILL BE SOME RISE IN TEMPERATURES WITH THE RELATIVELY THIN CLOUDINESS. EXPECT HIGHS THERE IN THE UPPER 50S TO LOWER 60S. TONIGHT...00Z NAM HITTING THE ISENTROPIC UPGLIDE PRETTY HARD...INDICATING A HIGH POTENTIAL FOR MODERATE RAIN OVER THE WESTERN PIEDMONT. THIS SEEMS TO BE AN OUTLIER AS OTHER MODEL GUIDANCE SUGGEST RAIN GRADUALLY DIMINISHING IN THE WAKE OF THE DEPARTING UPPER LEVEL SYSTEM. (THIS MAKES SENSE AS WEAK SUBSIDENCE IN THE WAKE OF THE DEPARTING DISTURBANCE SHOULD CURTAIL THE RAIN COVERAGE). BULK OF MODEL GUIDANCE DEPICTS SOME DEGREE OF CONVERGENCE ALONG THE 850MB TROUGH ALIGNED WEST-TO-EAST IN VICINITY THE NC/SC BORDER. THUS WILL DEPICT A DECREASING POP TREND LATE THIS EVENING- OVERNIGHT THOUGH MAINTAIN A DECENT CHANCE OF RAIN OVER THE SOUTHERN COUNTIES DUE TO PROXIMITY OF THE STALLED LOW LEVEL BOUNDARY. MIN TEMPS COOLER THAN PREVIOUS NIGHTS AS COOL AIR ASSOCIATED WITH THE CHILLY HIGH TO THE NORTH BECOMES ESTABLISHED. MIN TEMPS MID-UPPER 40S NORTH TO NEAR 50 SOUTH. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... AS OF 320 AM WEDNESDAY... THURSDAY AND THURSDAY NIGHT...FORECAST CONFIDENCE WANES A BIT. PARENT HIGH DRIFTS OFFSHORE OF NEW ENGLAND AND WEAKENS ITS INFLUENCE OVER CENTRAL NC. LACK OF A SCOURING MECHANISM SUGGEST THAT THE RESIDUAL CAD AIR MASS WILL REMAIN IN PLACE. NOT NOTING MUCH IN THE WAY OF ANY MECHANISM OF SUFFICIENT STRENGTH TO GENERATE WIDESPREAD RAIN THOUGH A WEAK UPPER LEVEL TROUGH WILL PASS NORTH OF OUR REGION THURSDAY AFTERNOON-EARLY EVENING. MODEL GUIDANCE DOES SUGGEST THE POTENTIAL FOR A SFC LOW TO DEVELOP OFF THE SE U.S. COAST AND DRIFT NEWD LATE THURSDAY-THURSDAY NIGHT. NAM STRONGER/MORE INLAND WITH THIS FEATURE WHILE THE GFS AND ECMWF HAVE A MUCH WEAKER VERSION MORE OFFSHORE. FOR NOW WILL HAVE POPS NO HIGHER THAN CHANCE AND MAINLY ASSOCIATED WITH THE PASSAGE OF THE UPPER TROUGH TO OUR NORTH THURSDAY AFTERNOON-EARLY EVENING....MAINTAINING A CHANCE POP OVERNIGHT (THOUGH FEEL THAT THIS MAY BE A WORSE CASE SCENARIO; MAY END UP HAVING MORE DRIZZLE THAN LIGHT RAIN). HIGH TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS VARYING FROM THE MID 50S NW TO THE MID 60S FAR SE. LOW TEMPS THURSDAY NIGHT NEAR 50 FAR WEST-NW TO THE MID 50S EAST. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... AS OF 210 PM WEDNESDAY... FRI-SAT NIGHT: LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON THE LATE-WEEK PATTERN. A MID LEVEL LOW WILL HOLD NEAR THE CO/NM BORDER... WELL SEPARATED FROM THE NORTHERN STREAM WHICH WILL FEATURE ONE POTENT SHORTWAVE TROUGH ZIPPING ESE ACROSS ONTARIO/SRN QUEBEC AND NRN NEW ENGLAND... AND A SECOND WAVE CROSSING BC AND THE CANADIAN PRAIRIE PROVINCES. THE WEAK MID LEVEL WAVE OVER THE MIDATLANTIC COAST EARLY FRI WILL SHIFT OFFSHORE DURING THE MORNING... AND SUBSIDENCE IN THE WAKE OF THIS WAVE WITH MID LEVEL SHORTWAVE RIDGING BETWEEN THE EXITING WAVE AND THE SOUTHWEST STATES LOW SHOULD BRING ABOUT A PERIOD OF LARGELY DRY WEATHER FRI INTO SAT. WILL RETAIN CHANCE POPS IN THE ERN CWA EARLY FRI TO ACCOUNT FOR LINGERING MOISTURE AND LIFT... BUT THEN WILL TREND BY MIDDAY TO DRY WEATHER AREAWIDE AS WEAK SURFACE HIGH PRESSURE BUILDS IN WITH DIFFLUENT DOWNGLIDE AT 850 MB. WHILE FORECAST SOUNDINGS SHOW ABUNDANT MID LEVEL DRY AIR ESPECIALLY LATER IN THE DAY... LOW LEVEL MOISTURE WILL TAKE LONGER TO DISPERSE... AND AS SUCH FORECAST SOUNDINGS SHOW WEAK INSTABILITY IN THE AFTERNOON... UP TO 500-750 J/KG OF MUCAPE MAINLY IN THE NW. WILL INCLUDE A LATE-DAY SLIGHT CHANCE OF A STORM OR TWO... WITH THE THREAT ENDING QUICKLY BY MID EVENING WITH THE LOSS OF HEATING. EXPECT DRY WEATHER OVERNIGHT INTO AT LEAST THE FIRST PART OF SATURDAY AS THE MID-HIGH LEVEL DRYING PERSISTS. A FEW SHOWERS MAY FORM LATE IN THE DAY ESPECIALLY OVER THE WRN AND SRN CWA... AS THE 850 MB ANTICYCLONE SHIFTS TO OUR EAST WITH THE ONSET OF SOUTHEASTERLY LOW LEVEL ATLANTIC-SOURCE FLOW... WHILE SRN STREAM ENERGY EJECTING FROM THE BASE OF THE LOW TOWARD NC RESULTS IN A GRADUAL INCREASE IN DPVA FROM THE SW. THE SOUTHWEST LOW STARTS TO OPEN UP AND LIFT NE SAT AND GETS PICKED UP BY THE WRN CANADA SHORTWAVE TROUGH... CULMINATING IN A LARGE BROAD TROUGH WITH A SLIGHT POSITIVE TILT EXTENDING THROUGH CENTRAL NOAM. MOISTURE EXTENT AND DEPTH OVER NC AS WELL AS FORCING FOR ASCENT WILL CONTINUE TO INCREASE FROM THE SW SAT NIGHT WITH THE MID LEVEL RIDGE AXIS SHIFTING TO OUR EAST... AND WILL INDICATE BOTH INCREASING POPS AND CLOUDS FROM THE SW LATE SAT THROUGH SAT NIGHT. IN ADDITION... THE STRONG WAVE CROSSING NEW ENGLAND WILL HELP DRAW DOWN A BACKDOOR FRONT TO NEAR THE VA/NC BORDER LATE SAT NIGHT WITH COOL HIGH PRESSURE OVER WRN QUEBEC NOSING SOUTHWARD... AND THIS MAY PROVIDE A LITTLE EXTRA LOW LEVEL FOCUS FOR PRECIP AS WE HEAD INTO EARLY SUNDAY. EXPECT SLIGHTLY ABOVE NORMAL TEMPS... WITH HIGHS IN THE 70S TO AROUND 80 (WARMER SAT THAN FRI) AND LOWS IN THE UPPER 50S TO LOWER 60S. FOR SUN-WED: OUR RAIN CHANCES APPEAR TO PEAK SUN/SUN NIGHT AS THE AXIS OF THE LONGWAVE TROUGH EXTENDING FROM LOW PRESSURE OVER SRN MANITOBA DOWN TO THE GULF STATES PIVOTS TO THE NE. THE SURFACE MAP WILL FEATURE AN EXPANSIVE FRONTAL SYSTEM... EXTENDING FROM AN OCCLUSION OVER THE SOUTH CENTRAL CANADA THROUGH THE GREAT LAKES... DOWN THROUGH THE MID SOUTH... GULF STATES... AND SOUTHEAST STATES... ALL SWEEPING TOWARD THE ENE SUN/MON. MODELS AGREE FAIRLY WELL ON INCREASING AND DEEPENING MOIST INFLOW FROM BOTH THE ATLANTIC AND GULF ALONG WITH STRENGTHENING DYNAMIC FORCING FOR ASCENT OVER NC... AND HAVE GONE WITH LIKELY POPS SUN/SUN NIGHT. COULD SEE SOME HEAVY RAIN. POPS SHOULD TREND DOWN IN COVERAGE DURING MONDAY BUT WE COULD END UP WITH SCATTERED STORMS IN THE AFTERNOON... AS WE SEEM TO GET A MID LEVEL DRY PUNCH INTO THE WARM SECTOR AS THE BROAD TROUGH AXIS SLOWLY LIFTS OUT TO OUR NE. LARGE LOW PRESSURE WILL THEN SIT AND SPIN OVER THE UPPER MIDWEST/ NORTHERN GREAT LAKES AND ADJACENT CANADIAN PROVINCES INTO MIDWEEK WITH ROUGHLY ZONAL FLOW OVER THE SRN HALF OF THE CONUS... SO EXPECT DRY WEATHER AND FAIRLY SEASONABLE TEMPS. THE GFS BRINGS A QUICK SHOT OF LIGHT PRECIP IN FROM THE WEST EARLY WED... BUT THIS DOESN`T LOOK WELL SUPPORTED AND WILL KEEP WED DRY FOR NOW. -GIH && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 144 PM WEDNESDAY... 24 HOUR TAF PERIOD: THE MAJORITY OF CEILINGS ACROSS THE AREA HAVE RISEN TO VFR LEVELS THIS AFTERNOON BUT RADAR SHOWS A LARGE AREA OF MODERATE TO HEAVY RAIN MOVING INTO THE NORTHWEST PIEDMONT AND WOULD NOT BE SURPRISED TO SEE CEILINGS DROP BACK TO MVFR THERE IN THE NEXT COUPLE OF HOURS. AS THIS NEW BATCH OF MOISTURE WORKS EASTWARD...EXPECT SIMILAR FALLS IN CEILINGS AT KFAY AND PERHAPS KRDU AND KRWI BUT THESE TWO STATIONS HAVE THE BEST CHANCE OF REMAINING VFR THROUGH THE TAF PERIOD. THAT BEING SAID FORECAST CONFIDENCE IN CEILINGS IS VERY LOW AT THIS TIME BUT HIGH RESOLUTION MODELS SHOW THAT PERHAPS THE NORTHEASTERN HALF OF THE AREA REMAIN VFR THROUGH THE PERIOD WITH THE BEST CHANCE FOR LOWER CEILINGS ACROSS THE SOUTH AND WEST. PERIODS OF RAIN CAN BE EXPECTED THROUGH THE AFTERNOON AND EVENING...PARTICULARLY IN THE SOUTHWEST WITH RAIN HOLDING OFF IN THE NORTHEAST UNTIL LATER IN THE AFTERNOON ON THURSDAY. VISIBILITIES ARE A LOW CONFIDENCE FORECAST AS WELL GIVEN THE PATTERN BUT SREF ENSEMBLE MEMBERS SHOW THAT THE LIKELIHOOD OF VISIBILITIES DROPPING BELOW VFR LEVELS OVERNIGHT IS LOW AND CURRENT OBSERVATIONAL PATTERNS LEND SUPPORT TO THIS SOLUTION BEING MORE LIKELY. WINDS WILL REMAIN OUT OF THE NORTHEAST THROUGH THE PERIOD AT 5-10 KTS. LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE RETURN TO VFR CONDITIONS ON TUESDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS NEAR TERM...RAH SHORT TERM...WSS LONG TERM...HARTFIELD AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
144 PM EDT WED APR 15 2015 .SYNOPSIS...COOL HIGH PRESSURE WILL BUILD SOUTH INTO CENTRAL NC TODAY AND REMAIN OVER THE REGION THROUGH THURSDAY. AN AREA OF LOW PRESSURE WILL DRIFT NORTHEAST OFF OF THE SOUTHEAST U.S. COAST LATE THURSDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1100 AM WEDNESDAY... A COMBINATION OF UPPER LEVEL DIVERGENCE...AN APPROACHING 850 MB TROUGH...AND THE SOUTHWARD ADVANCEMENT OF A SURFACE COLD FRONT HAS LEAD TO A MIX OF FORCING MECHANISMS THAT HAVE CONTRIBUTED TO WIDESPREAD PRECIPITATION FALLING ACROSS AT LEAST THE WESTERN HALF OF THE STATE. FURTHER TO THE NORTH AND EAST...DEWPOINTS ARE CONSIDERABLY LOWER AS A SECONDARY SURGE OF DRIER AIR IS MOVING IN FROM THE NORTH. COUPLE THAT WITH HIGHER CLOUD BASES AND PRECIPITATION TRYING TO MOVE EASTWARD IS RUNNING INTO A LOT OF RESISTANCE EAST OF ROUTE 1. RELATIVE HUMIDITY CROSS SECTIONS FROM THE HRRR HAVE SHOWN THE TEMPORARY LIFTING OF THE CLOUD BASES BUT ALSO DEPICT A SECONDARY SURGE OF MOISTURE THAT LOWERS CLOUD BASES AND INCREASES CHANCES FOR PRECIPITATION ONCE AGAIN THIS AFTERNOON. A LOOK AT THE CONVECTING ALLOWING MODELS CONFIRMS THIS AS THEY HOLD OFF PRECIPITATION THROUGH 18Z BUT THEN BRING WIDESPREAD RAIN TO THE ENTIRE AREA LATER INTO THE AFTERNOON AND EVENING. HIGH TEMPERATURES WILL BE TRICKY TODAY BUT EXPECT LOWEST TEMPS IN THE NORTHWEST PIEDMONT WHERE HIGHS HAVE MOST LIKELY ALREADY BEEN ACHIEVED. TO THE EAST...THERE WILL BE SOME RISE IN TEMPERATURES WITH THE RELATIVELY THIN CLOUDINESS. EXPECT HIGHS THERE IN THE UPPER 50S TO LOWER 60S. TONIGHT...00Z NAM HITTING THE ISENTROPIC UPGLIDE PRETTY HARD...INDICATING A HIGH POTENTIAL FOR MODERATE RAIN OVER THE WESTERN PIEDMONT. THIS SEEMS TO BE AN OUTLIER AS OTHER MODEL GUIDANCE SUGGEST RAIN GRADUALLY DIMINISHING IN THE WAKE OF THE DEPARTING UPPER LEVEL SYSTEM. (THIS MAKES SENSE AS WEAK SUBSIDENCE IN THE WAKE OF THE DEPARTING DISTURBANCE SHOULD CURTAIL THE RAIN COVERAGE). BULK OF MODEL GUIDANCE DEPICTS SOME DEGREE OF CONVERGENCE ALONG THE 850MB TROUGH ALIGNED WEST-TO-EAST IN VICINITY THE NC/SC BORDER. THUS WILL DEPICT A DECREASING POP TREND LATE THIS EVENING- OVERNIGHT THOUGH MAINTAIN A DECENT CHANCE OF RAIN OVER THE SOUTHERN COUNTIES DUE TO PROXIMITY OF THE STALLED LOW LEVEL BOUNDARY. MIN TEMPS COOLER THAN PREVIOUS NIGHTS AS COOL AIR ASSOCIATED WITH THE CHILLY HIGH TO THE NORTH BECOMES ESTABLISHED. MIN TEMPS MID-UPPER 40S NORTH TO NEAR 50 SOUTH. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... AS OF 320 AM WEDNESDAY... THURSDAY AND THURSDAY NIGHT...FORECAST CONFIDENCE WANES A BIT. PARENT HIGH DRIFTS OFFSHORE OF NEW ENGLAND AND WEAKENS ITS INFLUENCE OVER CENTRAL NC. LACK OF A SCOURING MECHANISM SUGGEST THAT THE RESIDUAL CAD AIR MASS WILL REMAIN IN PLACE. NOT NOTING MUCH IN THE WAY OF ANY MECHANISM OF SUFFICIENT STRENGTH TO GENERATE WIDESPREAD RAIN THOUGH A WEAK UPPER LEVEL TROUGH WILL PASS NORTH OF OUR REGION THURSDAY AFTERNOON-EARLY EVENING. MODEL GUIDANCE DOES SUGGEST THE POTENTIAL FOR A SFC LOW TO DEVELOP OFF THE SE U.S. COAST AND DRIFT NEWD LATE THURSDAY-THURSDAY NIGHT. NAM STRONGER/MORE INLAND WITH THIS FEATURE WHILE THE GFS AND ECMWF HAVE A MUCH WEAKER VERSION MORE OFFSHORE. FOR NOW WILL HAVE POPS NO HIGHER THAN CHANCE AND MAINLY ASSOCIATED WITH THE PASSAGE OF THE UPPER TROUGH TO OUR NORTH THURSDAY AFTERNOON-EARLY EVENING....MAINTAINING A CHANCE POP OVERNIGHT (THOUGH FEEL THAT THIS MAY BE A WORSE CASE SCENARIO; MAY END UP HAVING MORE DRIZZLE THAN LIGHT RAIN). HIGH TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS VARYING FROM THE MID 50S NW TO THE MID 60S FAR SE. LOW TEMPS THURSDAY NIGHT NEAR 50 FAR WEST-NW TO THE MID 50S EAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 305 AM WEDNESDAY... FRIDAY THROUGH SATURDAY NIGHT: S/W RIDING IS EXPECTED TO BUILD ACROSS THE AREA DURING THIS TIME FRAME... WITH THE LINGERING COLD AIR DAMMING AIR MASS SLOWLY MIXING OUT AS THE SURFACE HIGH TO THE NORTH MOVES WELL OFF THE NORTHEAST U.S. COAST ON FRIDAY. BOTH THE GFS AND NAM SHOW DRIER AIR ALOFT WORKING INTO THE AREA ON FRIDAY AND LINGERING THROUGH A GOOD PART OF SATURDAY. THUS... WILL CONTINUE THE TREND OF THE PAST FEW FORECASTS AND LOWER POPS DURING THIS TIME FRAME. WILL HOLD ONTO A SLIGHT CHANCES FOR SHOWERS ON FRIDAY AS A WEAK TRIALING COLD FRONT/SURFACE TROUGH MOVES INTO THE AREA FOR FRIDAY AFTERNOON AND WASHES OUT. DRY CONDITIONS ARE NOW EXPECTED FOR FRIDAY NIGHT INTO SATURDAY MORNING. THE MID LEVEL RIDGE AXIS WILL SLOWLY SHIFT TO THE EAST OF THE AREA LATE SATURDAY INTO SATURDAY NIGHT... ALLOWING FOR CHANCES FOR SHOWERS TO INCREASE IN A WEST TO EAST FASHION. FOR NOW WILL LIMIT ANY CHANCE POPS ON SATURDAY TO THE WESTERN HALF OF THE AREA... WITH CHANCES INCREASING ON SATURDAY NIGHT. WRT TO HIGH AND LOW TEMPS DURING THIS TIME FRAME... GIVEN WE SHOULD SEE SOME SUN DURING THIS PERIOD WITH SKIES PARTLY SUNNY AT TIMES... THINK HIGH TEMPS ON FRIDAY WILL GENERALLY BE IN THE LOWER TO MID 70S... WITH HIGHS ON SATURDAY EXPECTED TO RANGE FROM THE MID TO UPPER 70S (PERHAPS A FEW LOCATIONS TOUCHING THE 80 DEGREE MARK ACROSS THE SOUTHEAST/EAST). LOW TEMPS ARE EXPECTED TO BE ABOVE NORMAL IN THE UPPER 50S TO LOWER 60S. SUNDAY THROUGH TUESDAY: MEDIUM RANGE MODELS HAVE COME INTO BETTER AGREEMENT FOR THE LATTER HALF OF THE EXTENDED. THE MID TO UPPER LEVEL LOW AFFECTING THE CENTRAL ROCKIES AND FOUR CORNERS REGION TODAY SHOULD SLOWLY SHIFT EASTWARD OVER THE COURSE OF THE WEEK... BEFORE BEGINNING TO ACCELERATE EASTWARD AND PERHAPS NORTHWARD AS AN AMPLIFYING NORTHERN STREAM SYSTEM MOVES INTO THE NORTHERN PLAINS ON SATURDAY. REGARDLESS IF THESE TWO FEATURES COMPLETELY PHASE WE SHOULD SEE A MORE AMPLIFIED MID/UPPER FLOW PATTERN DEVELOP ACROSS THE EASTERN HALF OF THE COUNTRY BY LATE THIS WEEKEND INTO EARLY NEXT WEEK. THIS WILL HELP INCREASE SOUTHWESTERLY MID LEVEL FLOW ACROSS THE AREA ON SUNDAY WITH A GOOD CHANCES FOR SHOWERS AND PERHAPS SOME STORMS SUNDAY INTO SUNDAY NIGHT. WE COULD SEE SOME SORT OF DAMMING REFLECTION EXTENDING DOWN INTO THE AREA FROM THE NORTH ON SUNDAY (WITH A POSSIBLE CAD BOUNDARY DEVELOPING ACROSS CENTRAL NC). HOWEVER... STILL A LITTLE TO EARLY TO TELL HOW MUCH LINGERING DRY AIR WE WILL HAVE AT THE SURFACE/LOW LEVELS WHEN PRECIP SPREADS BACK INTO THE AREA. THE LEAD DISTURBANCE IS EXPECTED TO PUSH TO THE EAST OF THE AREA BY MONDAY MORNING... WITH THE LEAD SURFACE COLD FRONT EXPECTED TO MOVE THROUGH THE AREA BY MONDAY AFTERNOON/NIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO BUILD BACK INTO THE REGION ON TUESDAY... WITH A RETURN TO DRY WEATHER BY AT LEAST TUESDAY AFTERNOON. WRT TO TEMPS... WILL TREND TEMPS COOLER ON SUNDAY WITH THE EXPECTED PRECIP... AND TEMPS MAY EVEN BE MUCH COOLER ACROSS THE NW PIEDMONT. FOR NOW WIL THERE MAY BE A BRIEF PERIOD AFTER 14Z WHEN CEILINGS MAY BRIEFLY LIFT IN TO THE MVFR RANGE BEFORE ANOTHER AREA OF RAIN OVERSPREADS CENTRAL NC FROM THE WEST BY MID DAY-EARLY AFTERNOON....LOWERING CEILINGS BACK INTO THE IFR CATEGORY. THIS AREA OF RAIN SHOULD EXIT THE REGION LATE TONIGHT WITH SOME IMPROVEMENT IN CEILINGS POSSIBLE LATE TONIGHT INTO EARLY THURSDAY THOUGH EXPECT MVFR/LOW END VFR CEILINGS. L GO CLOSE TO WPC... WITH HIGHS IN THE UPPER 60S TO LOWER 70S. HIGHS EXPECTED MONDAY IN THE LOWER TO UPPER 70S... BEFORE A CATEGORY OR TWO COOLER ON TUESDAY. OVERNIGHT LOWS SHOULD REMAIN ABOVE NORMAL GENERALLY... WITH LOWS IN THE 50S TO NEAR 60 SE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 144 PM WEDNESDAY... 24 HOUR TAF PERIOD: THE MAJORITY OF CEILINGS ACROSS THE AREA HAVE RISEN TO VFR LEVELS THIS AFTERNOON BUT RADAR SHOWS A LARGE AREA OF MODERATE TO HEAVY RAIN MOVING INTO THE NORTHWEST PIEDMONT AND WOULD NOT BE SURPRISED TO SEE CEILINGS DROP BACK TO MVFR THERE IN THE NEXT COUPLE OF HOURS. AS THIS NEW BATCH OF MOISTURE WORKS EASTWARD...EXPECT SIMILAR FALLS IN CEILINGS AT KFAY AND PERHAPS KRDU AND KRWI BUT THESE TWO STATIONS HAVE THE BEST CHANCE OF REMAINING VFR THROUGH THE TAF PERIOD. THAT BEING SAID FORECAST CONFIDENCE IN CEILINGS IS VERY LOW AT THIS TIME BUT HIGH RESOLUTION MODELS SHOW THAT PERHAPS THE NORTHEASTERN HALF OF THE AREA REMAIN VFR THROUGH THE PERIOD WITH THE BEST CHANCE FOR LOWER CEILINGS ACROSS THE SOUTH AND WEST. PERIODS OF RAIN CAN BE EXPECTED THROUGH THE AFTERNOON AND EVENING...PARTICULARLY IN THE SOUTHWEST WITH RAIN HOLDING OFF IN THE NORTHEAST UNTIL LATER IN THE AFTERNOON ON THURSDAY. VISIBILITIES ARE A LOW CONFIDENCE FORECAST AS WELL GIVEN THE PATTERN BUT SREF ENSEMBLE MEMBERS SHOW THAT THE LIKELIHOOD OF VISIBILITIES DROPPING BELOW VFR LEVELS OVERNIGHT IS LOW AND CURRENT OBSERVATIONAL PATTERNS LEND SUPPORT TO THIS SOLUTION BEING MORE LIKELY. WINDS WILL REMAIN OUT OF THE NORTHEAST THROUGH THE PERIOD AT 5-10 KTS. LONG TERM: UNSETTLED PATTERN CONTINUES WITH CHANCES FOR ADVERSE CONDITIONS THROUGH THE WEEKEND...AND ON SUNDAY IN PARTICULAR AS A FRONTAL ZONE CROSSES THE AREA THROUGH MONDAY MIDDAY WITH A POSSIBLE RETURN TO VFR CONDITIONS ON TUESDAY. && $$ SYNOPSIS...WSS NEAR TERM...RAH SHORT TERM...WSS LONG TERM...BSD AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1058 AM EDT WED APR 15 2015 .SYNOPSIS...COOL HIGH PRESSURE WILL BUILD SOUTH INTO CENTRAL NC TODAY AND REMAIN OVER THE REGION THROUGH THURSDAY. AN AREA OF LOW PRESSURE WILL DRIFT NORTHEAST OFF OF THE SOUTHEAST U.S. COAST LATE THURSDAY THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1100 AM WEDNESDAY... A COMBINATION OF UPPER LEVEL DIVERGENCE...AN APPROACHING 850 MB TROUGH...AND THE SOUTHWARD ADVANCEMENT OF A SURFACE COLD FRONT HAS LEAD TO A MIX OF FORCING MECHANISMS THAT HAVE CONTRIBUTED TO WIDESPREAD PRECIPITATION FALLING ACROSS AT LEAST THE WESTERN HALF OF THE STATE. FURTHER TO THE NORTH AND EAST...DEWPOINTS ARE CONSIDERABLY LOWER AS A SECONDARY SURGE OF DRIER AIR IS MOVING IN FROM THE NORTH. COUPLE THAT WITH HIGHER CLOUD BASES AND PRECIPITATION TRYING TO MOVE EASTWARD IS RUNNING INTO A LOT OF RESISTANCE EAST OF ROUTE 1. RELATIVE HUMIDITY CROSS SECTIONS FROM THE HRRR HAVE SHOWN THE TEMPORARY LIFTING OF THE CLOUD BASES BUT ALSO DEPICT A SECONDARY SURGE OF MOISTURE THAT LOWERS CLOUD BASES AND INCREASES CHANCES FOR PRECIPITATION ONCE AGAIN THIS AFTERNOON. A LOOK AT THE CONVECTING ALLOWING MODELS CONFIRMS THIS AS THEY HOLD OFF PRECIPITATION THROUGH 18Z BUT THEN BRING WIDESPREAD RAIN TO THE ENTIRE AREA LATER INTO THE AFTERNOON AND EVENING. HIGH TEMPERATURES WILL BE TRICKY TODAY BUT EXPECT LOWEST TEMPS IN THE NORTHWEST PIEDMONT WHERE HIGHS HAVE MOST LIKELY ALREADY BEEN ACHIEVED. TO THE EAST...THERE WILL BE SOME RISE IN TEMPERATURES WITH THE RELATIVELY THIN CLOUDINESS. EXPECT HIGHS THERE IN THE UPPER 50S TO LOWER 60S. TONIGHT...00Z NAM HITTING THE ISENTROPIC UPGLIDE PRETTY HARD...INDICATING A HIGH POTENTIAL FOR MODERATE RAIN OVER THE WESTERN PIEDMONT. THIS SEEMS TO BE AN OUTLIER AS OTHER MODEL GUIDANCE SUGGEST RAIN GRADUALLY DIMINISHING IN THE WAKE OF THE DEPARTING UPPER LEVEL SYSTEM. (THIS MAKES SENSE AS WEAK SUBSIDENCE IN THE WAKE OF THE DEPARTING DISTURBANCE SHOULD CURTAIL THE RAIN COVERAGE). BULK OF MODEL GUIDANCE DEPICTS SOME DEGREE OF CONVERGENCE ALONG THE 850MB TROUGH ALIGNED WEST-TO-EAST IN VICINITY THE NC/SC BORDER. THUS WILL DEPICT A DECREASING POP TREND LATE THIS EVENING- OVERNIGHT THOUGH MAINTAIN A DECENT CHANCE OF RAIN OVER THE SOUTHERN COUNTIES DUE TO PROXIMITY OF THE STALLED LOW LEVEL BOUNDARY. MIN TEMPS COOLER THAN PREVIOUS NIGHTS AS COOL AIR ASSOCIATED WITH THE CHILLY HIGH TO THE NORTH BECOMES ESTABLISHED. MIN TEMPS MID-UPPER 40S NORTH TO NEAR 50 SOUTH. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... AS OF 320 AM WEDNESDAY... THURSDAY AND THURSDAY NIGHT...FORECAST CONFIDENCE WANES A BIT. PARENT HIGH DRIFTS OFFSHORE OF NEW ENGLAND AND WEAKENS ITS INFLUENCE OVER CENTRAL NC. LACK OF A SCOURING MECHANISM SUGGEST THAT THE RESIDUAL CAD AIR MASS WILL REMAIN IN PLACE. NOT NOTING MUCH IN THE WAY OF ANY MECHANISM OF SUFFICIENT STRENGTH TO GENERATE WIDESPREAD RAIN THOUGH A WEAK UPPER LEVEL TROUGH WILL PASS NORTH OF OUR REGION THURSDAY AFTERNOON-EARLY EVENING. MODEL GUIDANCE DOES SUGGEST THE POTENTIAL FOR A SFC LOW TO DEVELOP OFF THE SE U.S. COAST AND DRIFT NEWD LATE THURSDAY-THURSDAY NIGHT. NAM STRONGER/MORE INLAND WITH THIS FEATURE WHILE THE GFS AND ECMWF HAVE A MUCH WEAKER VERSION MORE OFFSHORE. FOR NOW WILL HAVE POPS NO HIGHER THAN CHANCE AND MAINLY ASSOCIATED WITH THE PASSAGE OF THE UPPER TROUGH TO OUR NORTH THURSDAY AFTERNOON-EARLY EVENING....MAINTAINING A CHANCE POP OVERNIGHT (THOUGH FEEL THAT THIS MAY BE A WORSE CASE SCENARIO; MAY END UP HAVING MORE DRIZZLE THAN LIGHT RAIN). HIGH TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS VARYING FROM THE MID 50S NW TO THE MID 60S FAR SE. LOW TEMPS THURSDAY NIGHT NEAR 50 FAR WEST-NW TO THE MID 50S EAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 305 AM WEDNESDAY... FRIDAY THROUGH SATURDAY NIGHT: S/W RIDING IS EXPECTED TO BUILD ACROSS THE AREA DURING THIS TIME FRAME... WITH THE LINGERING COLD AIR DAMMING AIR MASS SLOWLY MIXING OUT AS THE SURFACE HIGH TO THE NORTH MOVES WELL OFF THE NORTHEAST U.S. COAST ON FRIDAY. BOTH THE GFS AND NAM SHOW DRIER AIR ALOFT WORKING INTO THE AREA ON FRIDAY AND LINGERING THROUGH A GOOD PART OF SATURDAY. THUS... WILL CONTINUE THE TREND OF THE PAST FEW FORECASTS AND LOWER POPS DURING THIS TIME FRAME. WILL HOLD ONTO A SLIGHT CHANCES FOR SHOWERS ON FRIDAY AS A WEAK TRIALING COLD FRONT/SURFACE TROUGH MOVES INTO THE AREA FOR FRIDAY AFTERNOON AND WASHES OUT. DRY CONDITIONS ARE NOW EXPECTED FOR FRIDAY NIGHT INTO SATURDAY MORNING. THE MID LEVEL RIDGE AXIS WILL SLOWLY SHIFT TO THE EAST OF THE AREA LATE SATURDAY INTO SATURDAY NIGHT... ALLOWING FOR CHANCES FOR SHOWERS TO INCREASE IN A WEST TO EAST FASHION. FOR NOW WILL LIMIT ANY CHANCE POPS ON SATURDAY TO THE WESTERN HALF OF THE AREA... WITH CHANCES INCREASING ON SATURDAY NIGHT. WRT TO HIGH AND LOW TEMPS DURING THIS TIME FRAME... GIVEN WE SHOULD SEE SOME SUN DURING THIS PERIOD WITH SKIES PARTLY SUNNY AT TIMES... THINK HIGH TEMPS ON FRIDAY WILL GENERALLY BE IN THE LOWER TO MID 70S... WITH HIGHS ON SATURDAY EXPECTED TO RANGE FROM THE MID TO UPPER 70S (PERHAPS A FEW LOCATIONS TOUCHING THE 80 DEGREE MARK ACROSS THE SOUTHEAST/EAST). LOW TEMPS ARE EXPECTED TO BE ABOVE NORMAL IN THE UPPER 50S TO LOWER 60S. SUNDAY THROUGH TUESDAY: MEDIUM RANGE MODELS HAVE COME INTO BETTER AGREEMENT FOR THE LATTER HALF OF THE EXTENDED. THE MID TO UPPER LEVEL LOW AFFECTING THE CENTRAL ROCKIES AND FOUR CORNERS REGION TODAY SHOULD SLOWLY SHIFT EASTWARD OVER THE COURSE OF THE WEEK... BEFORE BEGINNING TO ACCELERATE EASTWARD AND PERHAPS NORTHWARD AS AN AMPLIFYING NORTHERN STREAM SYSTEM MOVES INTO THE NORTHERN PLAINS ON SATURDAY. REGARDLESS IF THESE TWO FEATURES COMPLETELY PHASE WE SHOULD SEE A MORE AMPLIFIED MID/UPPER FLOW PATTERN DEVELOP ACROSS THE EASTERN HALF OF THE COUNTRY BY LATE THIS WEEKEND INTO EARLY NEXT WEEK. THIS WILL HELP INCREASE SOUTHWESTERLY MID LEVEL FLOW ACROSS THE AREA ON SUNDAY WITH A GOOD CHANCES FOR SHOWERS AND PERHAPS SOME STORMS SUNDAY INTO SUNDAY NIGHT. WE COULD SEE SOME SORT OF DAMMING REFLECTION EXTENDING DOWN INTO THE AREA FROM THE NORTH ON SUNDAY (WITH A POSSIBLE CAD BOUNDARY DEVELOPING ACROSS CENTRAL NC). HOWEVER... STILL A LITTLE TO EARLY TO TELL HOW MUCH LINGERING DRY AIR WE WILL HAVE AT THE SURFACE/LOW LEVELS WHEN PRECIP SPREADS BACK INTO THE AREA. THE LEAD DISTURBANCE IS EXPECTED TO PUSH TO THE EAST OF THE AREA BY MONDAY MORNING... WITH THE LEAD SURFACE COLD FRONT EXPECTED TO MOVE THROUGH THE AREA BY MONDAY AFTERNOON/NIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO BUILD BACK INTO THE REGION ON TUESDAY... WITH A RETURN TO DRY WEATHER BY AT LEAST TUESDAY AFTERNOON. WRT TO TEMPS... WILL TREND TEMPS COOLER ON SUNDAY WITH THE EXPECTED PRECIP... AND TEMPS MAY EVEN BE MUCH COOLER ACROSS THE NW PIEDMONT. FOR NOW WIL THERE MAY BE A BRIEF PERIOD AFTER 14Z WHEN CEILINGS MAY BRIEFLY LIFT IN TO THE MVFR RANGE BEFORE ANOTHER AREA OF RAIN OVERSPREADS CENTRAL NC FROM THE WEST BY MID DAY-EARLY AFTERNOON....LOWERING CEILINGS BACK INTO THE IFR CATEGORY. THIS AREA OF RAIN SHOULD EXIT THE REGION LATE TONIGHT WITH SOME IMPROVEMENT IN CEILINGS POSSIBLE LATE TONIGHT INTO EARLY THURSDAY THOUGH EXPECT MVFR/LOW END VFR CEILINGS. L GO CLOSE TO WPC... WITH HIGHS IN THE UPPER 60S TO LOWER 70S. HIGHS EXPECTED MONDAY IN THE LOWER TO UPPER 70S... BEFORE A CATEGORY OR TWO COOLER ON TUESDAY. OVERNIGHT LOWS SHOULD REMAIN ABOVE NORMAL GENERALLY... WITH LOWS IN THE 50S TO NEAR 60 SE. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 747 AM WEDNESDAY... AN UNSETTLED WEATHER PATTERN WILL CONTINUE CENTRAL NC THROUGH THE REMAINDER OF THE WORK WEEK. COOL HIGH PRESSURE WILL BUILD SOUTHWARD INTO CENTRAL NC TODAY IN THE WAKE OF THE DEPARTING SFC COLD FRONT. THIS WILL SET UP A COLD AIR DAMMING REGIME AS MOISTURE WILL BE TRAPPED IN THE LOWER LAYERS OF THE ATMOSPHERE. THIS WILL RESULT IN WIDESPREAD IFR/MVFR CEILINGS THROUGH MUCH OF THE DAY. AN AREA OF RAIN IN ADVANCE OF AN UPPER LEVEL SYSTEM WILL OVERSPREAD CENTRAL NC THROUGH 15Z. THIS RAIN WILL AID TO MAINTAIN SATURATION IN THE LOWER LEVELS...LIKELY CAUSING THE MVFR/IFR CEILINGS TO PERSIST WELL INTO TEH AFTERNOON. THE UPPER LEVEL FEATURE WILL DEPART OUR AREA LATE THIS AFTERNOON. THIS SHOULD INITIATE A DECREASE IN RAIN COVERAGE...ESPECIALLY ACROSS THE NORTHERN COUNTIES. AREAS OF RAIN MAY PERSIST WELL INTO THE EVENING HOURS ACROSS THE SOUTH. CEILINGS MAY LIFT TO THE LOW END VFR CATEGORY MOST LOCATIONS LATE THIS EVENING. MVFR/LOW END VFR CEILINGS WILL LIKELY LINGER INTO THURSDAY AS THE LOW LEVEL AIR MASS REMAINS VERY MOIST. THE WEATHER PATTERN WILL REMAIN UNSETTLED ACROSS CENTRAL NC FRIDAY THROUGH SUNDAY. A RELATIVELY MOIST AIR MASS IN PLACE COUPLED A SERIES OF UPPER LEVEL SYSTEMS WILL CAUSES CHANCES FOR SHOWERS ALONG WITH PERIODS OF MVFR CEILINGS. && $$ SYNOPSIS...WSS NEAR TERM...RAH SHORT TERM...WSS LONG TERM...BSD AVIATION...WSS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1001 PM CDT THU APR 16 2015 .UPDATE... ISSUED AT 1001 PM CDT THU APR 16 2015 AS DISCUSSED BELOW...DRY AIR/LIGHT WINDS/A CLEAR SKY RESULTING IN TEMPERATURES QUICKLY FALLING THROUGH THE 40S. ALREADY SOME MID 30S REPORTED AT HETTINGER AND TIOGA. WILL BUMP OVERNIGHT LOWS DOWN A BIT MORE. PRODUCTS OUT IN THE NEXT 15-20 MINUTES. UPDATE ISSUED AT 639 PM CDT THU APR 16 2015 VERY DRY AIR FILTERING IN FROM THE NORTHWEST. LOWERED DEW POINTS A BIT CLOSER TO THE HRRR WHICH SEEMS TO BEST CAPTURE THIS...TEENS TO LOW 20S WEST AND CENTRAL...30S OVER MY FAR SOUTHEAST. WITH A CLEAR SKY AND WINDS TAPERING OFF...A GOOD SETUP FOR RADIATIONAL COOLING TONIGHT SO DID TWEAK TEMPS DOWN A TAD...LOW 30S OVER MY WEST. MAY NEED TO GO LOWER AND WILL MONITOR TRENDS OVER THE NEXT FEW HOURS. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 256 PM CDT THU APR 16 2015 H500 DEFORMATION ZONE BETWEEN THE CLOSED LOW ALOFT OVER THE FOUR CORNERS AREA AND THE WESTERLY FLOW OVER SOUTHERN CANADA FORMING A REGION OF SINKING/DRYING AIR OVER NORTHERN NORTH DAKOTA. AT THE SURFACE HIGH PRESSURE OVER WYOMING AND MONTANA WILL MOVE EAST. THESE FEATURES WILL CLEAR SKIES ACROSS THE REGION TONIGHT AND FRIDAY. USED THE RAWBLEND GUIDANCE WHICH HAS PERFORMED WELL PAST FEW NIGHT FOR MINIMUM TEMPERATURES. FOR HIGHS FRIDAY FOLLOWED THE EUROPEAN BIAS CORRECTED GUIDANCE. THIS GAVE HIGHS CLOSE TO 70. SEVERAL FACTORS COMBINING TO KEEP RELATIVE HUMIDITY LOW THROUGH THE SHORT TERM. VEGETATION STILL LARGELY DORMANT AND LACK OF SOIL MOISTURE KEEPS EVAPOTRANSPIRATION LOW. SO MAX RELATIVE HUMIDITY TONIGHT SHOULD BE WELL BELOW SATURATION AND IN THE 70S...WITH MIN RELATIVE HUMIDITY FRIDAY AROUND 20 PERCENT. WHAT WILL KEEP FIRE WEATHER CONCERNS LOW WILL BE THE LACK OF WIND. EXPECTING NORTHERLY WINDS AROUND 10 MPH FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 256 PM CDT THU APR 16 2015 A COOL AND DREARY PATTERN THROUGH THE EXTENDED. WIDESPREAD RAINFALL IS LIKELY SATURDAY INTO SUNDAY. OCCASIONAL SPRINKLES ARE POSSIBLE TROUGH TUESDAY. THE UPPER LEVEL LOW CURRENTLY SPINNING AROUND THE FOUR CORNERS REGION OF THE SOUTHWEST CONUS WILL SLOWLY LIFT NORTHEAST OVER THE NEXT COUPLE OF DAYS. THIS LOW WILL TRANSPORT MOISTURE NORTHWARD. MOISTURE WILL COMBINE WITH AMPLE LIFT SUPPLIED BY ANOTHER LOW...AND COLD FRONT...PROPAGATING ACROSS SOUTHERN CANADA THIS WEEKEND. WIDESPREAD RAINFALL IS LIKELY ACROSS PORTIONS OF THE DAKOTAS AND MINNESOTA. AT THIS TIME THE 12 UTC GFS/ECMWF/SREF INDICATE THE HEAVIEST RAINFALL (HALF INCH OR GREATER) WILL FALL ACROSS SOUTHEAST NORTH DAKOTA AND WESTERN MINNESOTA. AS THE TWO LOWS PROPAGATE EASTWARD AND COMBINE THEY SHOULD CREATE A RATHER DEEP AND SLOW MOVING TROUGH ACROSS THE GREAT LAKES BY EARLY NEXT WEEK. IT APPEARS THIS WILL LEAD TO A RATHER STAGNANT PATTERN OVER THE NEXT WEEK WITH GENERALLY COOL AND CLOUDY CONDITIONS FOR MOST OF NORTH DAKOTA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 639 PM CDT THU APR 16 2015 A FEW HIGH CLOUDS ACROSS THE NORTH MOVING THROUGH TONIGHT...OTHERWISE A CLEAR SKY AND VFR CONDITIONS THROUGH THE 00Z PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...WAA LONG TERM...AJ AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
639 PM CDT THU APR 16 2015 .UPDATE... ISSUED AT 639 PM CDT THU APR 16 2015 VERY DRY AIR FILTERING IN FROM THE NORTHWEST. LOWERED DEW POINTS A BIT CLOSER TO THE HRRR WHICH SEEMS TO BEST CAPTURE THIS...TEENS TO LOW 20S WEST AND CENTRAL...30S OVER MY FAR SOUTHEAST. WITH A CLEAR SKY AND WINDS TAPERING OFF...A GOOD SETUP FOR RADIATIONAL COOLING TONIGHT SO DID TWEAK TEMPS DOWN A TAD...LOW 30S OVER MY WEST. MAY NEED TO GO LOWER AND WILL MONITOR TRENDS OVER THE NEXT FEW HOURS. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 256 PM CDT THU APR 16 2015 H500 DEFORMATION ZONE BETWEEN THE CLOSED LOW ALOFT OVER THE FOUR CORNERS AREA AND THE WESTERLY FLOW OVER SOUTHERN CANADA FORMING A REGION OF SINKING/DRYING AIR OVER NORTHERN NORTH DAKOTA. AT THE SURFACE HIGH PRESSURE OVER WYOMING AND MONTANA WILL MOVE EAST. THESE FEATURES WILL CLEAR SKIES ACROSS THE REGION TONIGHT AND FRIDAY. USED THE RAWBLEND GUIDANCE WHICH HAS PERFORMED WELL PAST FEW NIGHT FOR MINIMUM TEMPERATURES. FOR HIGHS FRIDAY FOLLOWED THE EUROPEAN BIAS CORRECTED GUIDANCE. THIS GAVE HIGHS CLOSE TO 70. SEVERAL FACTORS COMBINING TO KEEP RELATIVE HUMIDITY LOW THROUGH THE SHORT TERM. VEGETATION STILL LARGELY DORMANT AND LACK OF SOIL MOISTURE KEEPS EVAPOTRANSPIRATION LOW. SO MAX RELATIVE HUMIDITY TONIGHT SHOULD BE WELL BELOW SATURATION AND IN THE 70S...WITH MIN RELATIVE HUMIDITY FRIDAY AROUND 20 PERCENT. WHAT WILL KEEP FIRE WEATHER CONCERNS LOW WILL BE THE LACK OF WIND. EXPECTING NORTHERLY WINDS AROUND 10 MPH FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 256 PM CDT THU APR 16 2015 A COOL AND DREARY PATTERN THROUGH THE EXTENDED. WIDESPREAD RAINFALL IS LIKELY SATURDAY INTO SUNDAY. OCCASIONAL SPRINKLES ARE POSSIBLE TROUGH TUESDAY. THE UPPER LEVEL LOW CURRENTLY SPINNING AROUND THE FOUR CORNERS REGION OF THE SOUTHWEST CONUS WILL SLOWLY LIFT NORTHEAST OVER THE NEXT COUPLE OF DAYS. THIS LOW WILL TRANSPORT MOISTURE NORTHWARD. MOISTURE WILL COMBINE WITH AMPLE LIFT SUPPLIED BY ANOTHER LOW...AND COLD FRONT...PROPAGATING ACROSS SOUTHERN CANADA THIS WEEKEND. WIDESPREAD RAINFALL IS LIKELY ACROSS PORTIONS OF THE DAKOTAS AND MINNESOTA. AT THIS TIME THE 12 UTC GFS/ECMWF/SREF INDICATE THE HEAVIEST RAINFALL (HALF INCH OR GREATER) WILL FALL ACROSS SOUTHEAST NORTH DAKOTA AND WESTERN MINNESOTA. AS THE TWO LOWS PROPAGATE EASTWARD AND COMBINE THEY SHOULD CREATE A RATHER DEEP AND SLOW MOVING TROUGH ACROSS THE GREAT LAKES BY EARLY NEXT WEEK. IT APPEARS THIS WILL LEAD TO A RATHER STAGNANT PATTERN OVER THE NEXT WEEK WITH GENERALLY COOL AND CLOUDY CONDITIONS FOR MOST OF NORTH DAKOTA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 639 PM CDT THU APR 16 2015 A FEW HIGH CLOUDS ACROSS THE NORTH MOVING THROUGH TONIGHT...OTHERWISE A CLEAR SKY AND VFR CONDITIONS THROUGH THE 00Z PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...WAA LONG TERM...AJ AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
317 PM CDT WED APR 15 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 251 PM CDT WED APR 15 2015 FIRE WEATHER CONCERNS HIGHLIGHT THE SHORT TERM TONIGHT BUT WILL DIMINISH TOMORROW. A COLD FRONT ACROSS WESTERN NORTH DAKOTA HAS BEEN SLOWER TO MOVE EAST THAN EARLIER FORECAST. THE RESULT HAS BEEN AN EXTENDED PERIOD OF GUSTY SOUTHERLY WINDS ACROSS CENTRAL AND EASTERN NORTH DAKOTA UP THROUGH THIS AFTERNOON. THIS HAS RESULTED AN MULTIPLE FIRES ACROSS CENTRAL NORTH DAKOTA. IMPROVING CONDITIONS WILL FINALLY ARRIVE THIS EVENING AS THE FRONTAL BOUNDARY MOVES TO CENTRAL NORTH DAKOTA THEN TO THE EAST AFTER MIDNIGHT. THIS WILL BRING AN END TO THE STRONG SOUTHERLY WINDS. CLOUDS ARE BEING DRAWN UP THROUGH EASTERN SOUTH DAKOTA WITH SOME LIMITED LOW LEVEL MOISTURE. THE HRRR DOES GENERATE SOME LIGHT PRECIP ACROSS THE EAST...BUT GENERALLY EAST OF THE JAMES RIVER VALLEY THOUGH. MEASURABLE PRECIPITATION WILL BE MOST LIKELY ACROSS THE SOUTHWEST TONIGHT. BUT KEPT THE POPS LESS THAN 40 PERCENT. ON THURSDAY...COOLER TEMPERATURES WITH HIGHS 60 TO 65. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 251 PM CDT WED APR 15 2015 A WEAK COLD FRONTAL BOUNDARY SHIFTING THROUGH NORTHERN NORTH DAKOTA LATE THURSDAY NIGHT WILL UNDERGO FRONTOLYSIS AS IT SAGS SOUTH INTO CENTRAL NORTH DAKOTA FRIDAY MORNING. SPLIT FLOW REMAINS OVER NORTH DAKOTA FRIDAY WITH THE NORTHERN STREAM JUST GRAZING FAR NORTHERN NORTH DAKOTA/TURTLE MOUNTAINS. A CLOSED LOW OVER COLORADO SLOWLY EMERGES INTO THE CENTRAL PLAINS...WITH NORTH DAKOTA CAUGHT BETWEEN THESE TWO STREAMS FRIDAY AND WILL MOSTLY REMAIN IN A LULL FRIDAY WITH BENIGN WEATHER. FOR SATURDAY AND SATURDAY NIGHT...MODEL DATA CONTINUES TO SUGGEST SOME INTERACTION WITH THE CLOSED LOW AND ITS ASSOCIATED MOISTURE SPINNING INTO SOUTHERN NORTH DAKOTA...AND A STRONG SHORTWAVE TROUGH/SURFACE COLD FRONT VIA THE NORTHERN STREAM AS IT APPROACHES WESTERN NORTH DAKOTA 00Z SUNDAY. VARYING SOLUTIONS AS TO THE TIMING AND AREAL COVERAGE OF PRECIPITATION THAT IS FORECAST TO PUSH INTO NORTH DAKOTA SATURDAY AFTERNOON INTO SATURDAY NIGHT. THE GFS REPRESENTS THE FASTEST AND MOST WIDESPREAD PRECIPITATION SOLUTIONS...WITH CHANCES OF RAIN CROSSING THE SOUTHERN BORDER BEFORE 12Z SATURDAY. THE GEM/ECMWF REPRESENT SLOWER SOLUTIONS AND ARE MORE IN LINE WITH RAIN SHOWERS MAINLY CONFINED TO THE JAMES RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA LATE SATURDAY AFTERNOON THROUGH SUNDAY MORNING. A COLD THERMAL TROUGH/POCKET IS FORECAST TO FOLLOW SUNDAY NIGHT THROUGH MOST OF NEXT WEEK. GOOD AGREEMENT BETWEEN THE GFS AND ECMWF WITH THIS IDEA. 850MB TEMPS ARE FORECAST TO RANGE BETWEEN -2C TO -8C THROUGH THURSDAY. THIS WILL TRANSLATE TO AFTERNOON HIGH TEMPERATURES IN THE UPPER 40S TO MID 50S. CONCERNING FIRE WEATHER IN THE LONG TERM PERIOD...NOT ANTICIPATING ANY FIRE WEATHER CONCERNS FRIDAY OR SATURDAY. DESPITE A COOLING TREND SUNDAY ONWARD...STRONG WINDS AT TIMES WILL ALIGN WITH LOW RELATIVE HUMIDITIES ACROSS PORTIONS OF WESTERN AND CENTRAL NORTH DAKOTA AND WILL NEED TO MONITOR. STRONG NORTHWEST WINDS DEVELOPING BEHIND A COLD FRONT ACROSS WESTERN AND CENTRAL NORTH DAKOTA SUNDAY MAY WARRANT A WIND ADVISORY. IN ADDITION MINIMUM RELATIVE HUMIDITIES OF AROUND 25 PERCENT IN THE SOUTHWEST MAY ALSO WARRANT A FIRE WEATHER HEADLINE SUNDAY. THEN ON MONDAY THE STRONGEST WINDS AND LOWEST RELATIVE HUMIDITIES ARE ALIGNED IN SOUTH CENTRAL NORTH DAKOTA...THUS THIS REPRESENTS ANOTHER POTENTIAL FOR FIRE WEATHER HEADLINES. WEAKER WINDS ARE EXPECTED FOR TUESDAY AND WEDNESDAY WITH EVEN COOLER TEMPERATURES...WITH WIDESPREAD HIGHS IN THE 40S WEDNESDAY. NO SIGNIFICANT SYSTEMS/PRECIPITATION EVENTS SUNDAY THROUGH WEDNESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1242 PM CDT WED APR 15 2015 A COLD FRONT WAS SLOWLY PROPAGATING THROUGH THE WESTERN PART OF THE STATE. STRONG SOUTHERLY WINDS WILL REMAIN THE GREATEST FORECAST CONCERN AHEAD OF THIS FRONT AS IT CONTINUES TO DRIFT EAST. THE STRONGEST WINDS WILL GUST UP TO 35-40 KNOTS AT KJMS THROUGH THE AFTERNOON...WITH WINDS CALMING TO THE WEST. BEHIND THE BOUNDARY...WINDS WILL SHIFT FROM THE NORTHWEST THROUGH THE NIGHT. THERE WILL BE A SLIGHT CHANCE FOR LIGHT RAIN AT KDIK/KBIS EARLY THURSDAY MORNING. VFR CIGS/VSBYS ARE EXPECTED THROUGHOUT THE PERIOD. && .FIRE WEATHER... ISSUED AT 251 PM CDT WED APR 15 2015 RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT. WITH THE ADVANCING COLD FRONT THE STRONG SOUTHERLY WINDS WILL SUBSIDE THIS EVENING. AFTER 8 PM CDT COOLER TEMPERATURES...RISING RELATIVE HUMIDITY SHOULD END THE RED FLAG CONDITIONS. ON THURSDAY MINIMUM RELATIVE HUMIDITY WILL FALL INTO THE UPPER TEENS NORTHWEST. HOWEVER THE WINDS WILL BE MUCH LOWER. ALTHOUGH THE FIRE DANGER WILL BE ELEVATED CRITICAL FIRE WEATHER WILL NOT BE REACHED. && .BIS WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM CDT /7 PM MDT/ THIS EVENING FOR NDZ003>005-011>013-019>023-025-034>037-042-045>048-050-051. WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ005-013-023-025- 036-037-047-048-050-051. && $$ SHORT TERM...WAA LONG TERM...KS AVIATION...WAA/ZH FIRE WEATHER...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1244 AM CDT WED APR 15 2015 .UPDATE... ISSUED AT 1244 AM CDT WED APR 15 2015 MAIN CONCERN IS INCREASING WINDS THE PAST HOUR OR TWO...LIKELY ASSOCIATED WITH A STRENGTHENING LOW LEVEL JET. THIS MIXING WILL KEEP RELATIVE HUMIDITY VALUES IN THE 30 TO 35 PERCENT RANGE TO 40-50 PERCENT TOWARDS DAYBREAK. UPDATE ISSUED AT 1018 PM CDT TUE APR 14 2015 QUICK UPDATE TO EXPIRE THE RED FLAG WARNING ON TIME AT 03 UTC. THE REMAINDER OF THE FORECAST FOR THE OVERNIGHT IS ON TRACK AND BLENDED TO OBSERVED TRENDS THROUGH 03 UTC. UPDATE ISSUED AT 804 PM CDT TUE APR 14 2015 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. THE MAIN CONCERN IS THE INCREASING WIND FIELD IN THE 900-800 MB POST 03 UTC. THE 20-23 UTC ITERATIONS OF RAP SOUNDINGS HAVE CONSISTENTLY SHOWN 50-60KTS IN THE AFOREMENTIONED LAYER ACROSS SOUTH CENTRAL NORTH DAKOTA WITH ONLY A VERY SHALLOW DECOUPLED LAYER AT THE SURFACE. SHOULD THE BOUNDARY LAYER REMAIN MIXED TO ALLOW THE TRANSFER OF THIS HIGHER MOMENTUM AIR TO THE SURFACE...AN EXTENSION OF THE RED FLAG WARNING MAY BE NEEDED WITH POSSIBLE WIND HEADLINES. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 311 PM CDT TUE APR 14 2015 THE MAIN CONCERNS IN THE SHORT TERM REMAIN FIRE WEATHER (SEE FIRE WEATHER DISCUSSION BELOW) AND WINDS. GOOD MIXING TODAY HAS HELPED BOOST TEMPERATURES INTO THE 70S ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA. WINDS HAVE ALSO BEEN GUSTY WITH SPEEDS APPROACHING ADVISORY LEVELS OF 45 MPH IN SOME LOCATIONS. BUFR SOUNDINGS SUGGEST THE GUSTY WINDS WILL CONTINUE INTO EARLY EVENING BEFORE DIMINISHING TO SOME EXTENT. CONSIDERED ISSUING A WIND ADVISORY FOR A FEW HOURS THIS AFTERNOON...BUT DECIDED AGAINST IT FOR NOW SINCE WE HAVE BEEN ON THE LOWER END OF CRITERIA AND ONLY AT A LIMITED NUMBER OF REPORTING LOCATIONS. A COLD FRONT MOVES INTO WESTERN NORTH DAKOTA LATE TONIGHT INTO WEDNESDAY. THE FRONT IS SLOW TO PROGRESS EAST...AND WINDS ARE EXPECTED TO AGAIN INCREASE AHEAD OF THE BOUNDARY. WINDS COULD APPROACH ADVISORY LEVELS TOWARDS THE JAMES RIVER VALLEY ON WEDNESDAY...BUT AFTER COLLABORATION WITH WFO FGF...HAVE OPTED TO HOLD OFF ON ANY WIND HEADLINES FOR NOW. TEMPERATURES WILL BE MUCH COOLER ON WEDNESDAY BEHIND THE FRONT WITH HIGHS IN THE MID TO UPPER 50S WEST...AND NEAR 70 EAST. A FEW SHOWERS ARE POSSIBLE ALONG AND BEHIND THE FRONT...WITH THE HIGHER CHANCES ACROSS THE SOUTHWEST PART OF THE STATE. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 311 PM CDT TUE APR 14 2015 OVERALL PATTERN IS POINTING TOWARD A GRADUAL COOLING TREND AS WE MIGRATE DEEPER INTO THE LONG TERM PERIOD. SOME PROSPECTS OF LIGHT PRECIPITATION OCCUR WEDNESDAY NIGHT...WITH PERHAPS A MORE PRONOUNCED AREA COMING THROUGH SATURDAY NIGHT THROUGH SUNDAY. USED A BLEND OF THE NAM/SREF/ECMWF. THE GFS WAS OUSTED AS AN OUTLIER EARLY IN THE EXTENDED AS IT TRIED TO DEVELOP A CLOSED 700MB-500MB CLOSED LOW OVER WESTERN SOUTH DAKOTA WEDNESDAY NIGHT. FIRE WEATHER CONCERNS SHOULD BE ON THE DECREASE AFTER SATURDAY. WEDNESDAY NIGHT INTO SATURDAY...A SHORTWAVE TROUGH IN THE NORTHERN STREAM EASES INTO THE JAMES RIVER VALLEY BY 12Z THURSDAY. HAVE A CHC OF SHOWERS SLIDING ACROSS WESTERN INTO CENTRAL NORTH DAKOTA WEDNESDAY NIGHT...EXTENDING THROUGH 18Z THURSDAY INTO THE JAMES RIVER VALLEY. THEREAFTER...NORTHWEST FLOW THURSDAY AFTERNOON WILL GIVE WAY TO BROAD RIDGING FRIDAY THROUGH SATURDAY MORNING. LIGHT WINDS THURSDAY WITH NO FIRE WEATHER ISSUES EXPECTED. A WEAK COLD FRONT WILL SLIDE THROUGH THURSDAY NIGHT WITH BREEZY NORTHWEST WINDS SLATED FOR FRIDAY. THE STRONGEST WINDS ARE FORECAST IN THE JAMES RIVER VALLEY BETWEEN 20 AND 35 MPH...ALONG WITH MINIMUM RELATIVE HUMIDITIES AROUND 25 PERCENT. WILL NEED TO MONITOR THIS AREA CLOSELY FOR THE POSSIBILITY OF FIRE WEATHER HEADLINES. FOR SATURDAY... SOUTHERLY WINDS OF 15 TO 25 MPH WILL COMBINE WITH MINIMUM RELATIVE HUMIDITIES OF 25 TO 30 PERCENT ACROSS MOST OF WESTERN AND SOUTHERN NORTH DAKOTA. A MARGINAL CASE FOR FIRE WEATHER HEADLINES AND WILL CONTINUE TO MONITOR. SATURDAY NIGHT THROUGH TUESDAY...A STRONGER COLD FRONT MOVES THROUGH SATURDAY NIGHT WITH A CHANCE OF SHOWERS DEVELOPING WEST MOVING INTO CENTRAL NORTH DAKOTA. THE ECMWF DOES SHOW SOME BRIEF LINKAGE OF SOUTHERN STREAM MOISTURE AHEAD OF THE FRONT SATURDAY NIGHT BEING SCOOPED UP INTO CENTRAL NORTH DAKOTA PRIOR TO FRONTAL PASSAGE. OTHERWISE EXPECT A CHANCE OF SHOWERS CONTINUING INTO SUNDAY. COOLER TEMPERATURES ALONG WITH SLIGHT CHANCES FOR SHOWERS WILL FOLLOW SUNDAY THROUGH TUESDAY WITH AFTERNOON HIGHS IN THE 50S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1244 AM CDT WED APR 15 2015 THE MAIN FORECAST CONCERN WILL BE GUSTY SOUTHEAST WINDS AHEAD OF AN APPROACHING COLD FRONT. GUSTS WILL RANGE FROM 25-35 KNOTS AT KDIK/KBIS/KMOT...WITH KJMS INCREASING TO 25-35 KNOTS DURING THE EARLY MORNING. KISN IS NEAR A LOW PRESSURE TROUGH AND WINDS THERE EXPECTED TO BE SOUTHEAST AT AROUND 10-15 KNOTS. ADDED A WIND SHEAR COMPONENT WITH A 50 KNOT WIND AROUND 1400-2000FEET. THE SLOW MOVING COLD FRONT SHOULD MOVE THROUGH KISN BY AROUND 16Z...AND AT KDIK AROUND 18Z-20Z. THE STRONGEST WINDS AFTER 12Z SHOULD BE AT KJMS WITH STRONGEST WINDS FROM 15Z-24Z. VFR CONDITIONS WILL PREVAIL THROUGHOUT THE PERIOD WITH SOME MID TO HIGH CLOUDS ENCROACHING FROM MONTANA. && .FIRE WEATHER... ISSUED AT 1018 P CDT TUE APR 14 2015 ANOTHER CRITICAL FIRE WEATHER DAY IS POSSIBLE WEDNESDAY AHEAD OF A COLD FRONT MOVING ACROSS NORTH DAKOTA. RELATIVE HUMIDITY VALUES SHOULD NOT BE AS LOW AS TODAY (TUESDAY)...BUT STRONG SOUTH WINDS WILL AGAIN BE A CONCERN. WILL MAINTAIN THE FIRE WEATHER WATCH FROM BOTTINEAU COUNTY...SOUTH THROUGH EMMONS COUNTY...AND EAST TO OUR BORDER WITH WFO FGF FOR WEDNESDAY AFTERNOON AND EVENING. && .BIS WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM NOON CDT TODAY THROUGH THIS EVENING FOR NDZ004-005-012-013-022-023-025-035>037-046>048-050-051. && $$ UPDATE...JV SHORT TERM...CK LONG TERM...KS AVIATION...JV FIRE WEATHER...AYD
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
454 AM EDT WED APR 15 2015 .SYNOPSIS... HIGH PRESSURE TRACKS NORTH OF THE AREA TODAY...WITH LOW PRESSURE AND SCATTERED SHOWERS TO THE SOUTH. PERIODS OF UNSETTLED WEATHER FOR THE REMAINDER OF THE WEEK. COLD FRONT CROSSES ON SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... 430 AM UPDATE...UPDATED POPS AND WEATHER BASED ON CURRENT RADAR. THE HRRR MODEL SEEMS TO HAVE A GOOD HANDLE ON THE SLUG OF MOISTURE MOVING NORTHWARD. ...PREVIOUS DISCUSSION... THE FORECAST AREA WILL BE SANDWICHED BETWEEN WEAK HIGH PRESSURE MOVING WEST TO EAST ACROSS THE NORTH AND LOW PRESSURE TO THE SOUTH. HAVE KEPT CHANCE POPS ACROSS THE VIRGINIA ZONES DURING THE DAY TODAY AND SPREADING SLIGHTLY NORTHWARD DURING THE LATE MORNING HOURS. INSTABILITY IS NOT ALL THAT IMPRESSIVE TODAY...BUT THERE COULD BE A FEW RUMBLES OF THUNDER HEARD. FLOW BECOMES SOUTHEAST OVERNIGHT AND THIS WILL HELP TO INCREASE MOISTURE AND POPS. WENT WITH A BLEND OF MET AND MAV TEMPERATURES TODAY WHICH WAS A COUPLE OF DEGREES WARMER THAN WHAT WAS PREVIOUSLY FORECASTED. HOW MUCH CLEARING OCCURS ACROSS THE NORTH AND HOW FAR NORTH THE SHOWERS DRIFT COULD HAVE AN IMPACT ON AFTERNOON HIGH TEMPERATURES. NORTHERN HALF OF THE CWA WILL LIKELY BE WARMER THAN THE SOUTHERN HALF GIVEN THE EXPECTED CLEARER CONDITIONS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AN UPPER LEVEL WAVE EMERGES FROM THE CENTRAL PLAINS...NORTHEAST INTO THE OHIO VALLEY THURSDAY. THIS SYSTEM WILL PRODUCE ROUNDS OF SHOWERS ACROSS THE AREA THROUGH THURSDAY NIGHT. MODELS SHOW INSTABILITY TO OUR SOUTHWEST WITH CAPE VALUES FROM 1000 TO 2000 J/KG ACROSS CENTRAL KY. BUT THIS INSTABILITY NEVER MAKES IT INTO OUR AREA. THEREFORE...CODED MODERATE SHOWERS WITH NO THUNDER THURSDAY AND THURSDAY NIGHT. ON FRIDAY...CAPE VALUES INCREASES OVER THE AREA MAINLY ACROSS THE SOUTHERN HALF OF THE AREA DURING THE AFTERNOON HOURS. HOWEVER...IT DOES NOT APPEAR TO BE AN UPPER WAVE GENERATE ORGANIZED THUNDERSTORMS. THEREFORE...KEPT CHANCE POPS WITH MENTION OF THUNDER FRIDAY AFTERNOON AND EARLY EVENING. DRIER WEATHER EXPECTED FRIDAY NIGHT INTO SATURDAY AS A SFC HIGH PRESSURE BUILDS OVERHEAD. DECREASED POPS FOR THIS TIME PERIOD. HOWEVER...A COLD FRONT APPROACHES FROM THE NORTHWEST LATE SATURDAY...INCREASING THE CHANCES FOR ADDITIONAL ROUNDS OF SHOWERS. EXPECT MILD TEMPERATURES THROUGH THE PERIOD. WENT WITH THE ALL BLEND GUIDANCE FOR LOWS AND HIGHS. && .LONG TERM /SATURDAY THROUGH TUESDAY/... SRN STREAM DOMINATES THE CWA EARLY ON...WITH A WEAK WAVE MOVING THROUGH LATE FRI NT INTO SAT. A NRN STREAM S/W TROUGH MAY STILL DIG FAR ENOUGH S TO DRIVE A COLD FRONT AT LEAST INTO THE AREA LATE SAT. THIS MAY BRING A BRIEF INTERLUDE OF DRY TO ONLY SCHC POPS AT LEAST ACROSS THE N SAT NT INTO SUN. SRN STREAM UPPER LOW LIFTS OUT OF THE DEEP S LATER SUN INTO MON AND CROSSES THE CWA WITH ANOTHER ROUND OF PRECIPITATION. NRN STREAM TROUGH AMPLIFICATION OVER THE CENTRAL AND ERN CONUS BEGINS EARLY NEXT WEEK. MODELS ACTUALLY SHOW PHASING WITH THE SRN STREAM UPPER LEVEL LOW ONCE THAT FEATURE IS PASSED THE AREA. THIS LEADS TO A MILLER B TYPE SFC EVOLUTION WHICH BRINGS THE COLD FRONT ASSOCIATED WITH THE FADING PRIMARY LOW THROUGH THE AREA SUN NT INTO MON. THIS WOULD BE FOLLOWED BY DRYING DAY 7 NT. TEMPERATURES A BIT HIGHER EARLY ON BUT OTHERWISE CLOSE TO PREVIOUS WITH NO MAJOR DEVIATIONS FROM WPC INCLUDING THE NEW DAY 7. && .AVIATION /09Z WEDNESDAY THROUGH SUNDAY/... MAINLY VFR NORTH AND MVFR SOUTH CONDITIONS THROUGH 18Z. THERE WILL ALSO BE IFR CONDITIONS OVER EXTREME SOUTHWEST VIRGINIA AND THE MOUNTAINS. MOVED THE MVFR CIGS FURTHER NORTH INTO KHTS AND KCRW. AFTER 18Z CIGS WILL BECOME VFR IN AND AROUND KCRW...BUT SHOULD STAY MVFR OVER HTS. MVFR CIGS BREAKS UP AFTER 00Z. SHOWERS WILL SPREAD NORTH DURING THE DAY AND AFFECT KBKW...KHTS...AND KCRW. LIGHT NORTHEASTERLY WINDS WILL SWING TO THE SOUTHEAST DURING THE PERIOD. EXPECT GUSTY OF 15 TO 20 KTS IN KBKW. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY... FORECAST CONFIDENCE: MEDIUM TO HIGH ALTERNATE SCENARIOS: IFR/LIFR COULD BECOME MORE WIDESPREAD AND LAST LONGER THAN FORECASTED. HEAVY RAIN COULD REDUCE VISIBILITY FOR SHORT PERIODS OF TIME. 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 04/15/15 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 H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H M M BKW CONSISTENCY M M M H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H 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 06Z THURSDAY... IFR CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS AT VARIOUS TIMES THRU THE WEEK. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...FB/ARJ NEAR TERM...FB SHORT TERM...ARJ LONG TERM...TRM AVIATION...FB
AREA FORECAST DISCUSSION
NWS NORMAN OK
1055 PM CDT THU APR 16 2015 .DISCUSSION... THE 06Z AVIATION DISCUSSION FOLLOWS.... && .AVIATION... A LARGE CUTOFF UPPER-LEVEL LOW SPINNING OVER THE FOUR CORNERS REGION WILL CAUSE SPORADIC TSRA AND CLUSTERS OF TSRA OVER OK/N TX THROUGH TOMORROW NIGHT. IT IS EXTREMELY DIFFICULT TO TIME THE STORMS...SINCE THERE IS NO SINGLE FOCUS THAT WE CAN TRACK. SO...THE TAFS ARE BASED MAINLY ON THE CONSENSUS OF MODEL OUTPUT...WHICH IS ADMITTEDLY NOT VERY ACCURATE. THESE SAME MODELS SUGGEST LOW CLOUDS AND PERHAPS FOG WILL SPREAD NW ACROSS THE REGION TOWARD SUNRISE...AND WHILE THIS SCENARIO IS BELIEVABLE...IT IS UNLIKELY THAT CONDITIONS WILL BE QUITE AS BAD AS THE MODELS SUGGEST. GULF STRATUS LAYERS TYPICALLY HAVE BASES AROUND 1500 FT OVER MOST OF OK/N TX THIS TIME OF YEAR...WHICH IS WHAT WE HAVE IN THE PRELIMINARY TAFS. SOME IF CONDITIONS WARRANT...SOME CHANGES TO THIS FORECAST MAY BE MADE BEFORE THE ACTUAL TAF ISSUANCE AT ABOUT 0530Z. && .PREV DISCUSSION... /ISSUED 924 PM CDT THU APR 16 2015/ DISCUSSION... A COMPLEX OF THUNDERSTORMS HAD DEVELOPED OVER NORTHWEST OKLAHOMA BY LATE THIS EVENING. A WAKE LOW APPEARS TO BE DEVELOPING WITHIN THE COMPLEX...LEADING TO RATHER STRONG WINDS IN ELLIS COUNTY. THESE WINDS MAY EXPAND OR CONTINUE TO SHIFT TO THE SOUTH WITH TIME. THEY ARE TOO SMALL-SCALE TO REPRESENT IN A REASONABLE WAY IN THE FORECAST. SHORT-RANGE MODELS SHOW A GENERAL TENDENCY OF THE EXISTING STORM COMPLEX TO START SHIFTING EAST WITH TIME...REACHING CENTRAL AND/OR NORTH-CENTRAL OKLAHOMA SEVERAL HOURS AFTER MIDNIGHT. DETAILS REMAIN SKETCHY...BUT THE OVERALL CONCEPT IS CONSISTENT AND IS REASONABLE...GIVEN THE CURRENT SITUATION. THE FORECAST WAS UPDATED EARLIER TO ACCOUNT FOR RAIN TRENDS AND THEIR LARGE-SCALE EFFECTS. WE WILL CONTINUE TO UPDATE AS NEEDED TO KEEP UP-TO-DATE WITH THE STORM SYSTEM AS IT EVOLVES TONIGHT. PREV DISCUSSION... /ISSUED 626 PM CDT THU APR 16 2015/ DISCUSSION... THE 00Z AVIATION DISCUSSION FOLLOWS.... AVIATION... SCT TSRA...A FEW STRONG/SEVERE...WILL OCCUR OVER W OK/N TX W/KSPS THIS EVENING. TAFS MENTION TSRA ONLY WHERE PROBABILITY IS GREATER THAN 50 PERCENT THIS EVENING. A SMALL STORM COMPLEX MAY FORM AROUND MIDNIGHT FROM EXISTING STORMS...AND SPEED E ALONG THE KS/OK BORDER. IF THIS HAPPENS...STRONG W WINDS WILL OCCUR AT KPNC. THE KPNC TAF INCLUDES THIS EVENT...BUT NOT AS STRONG AS IT MIGHT BE. TOMORROW MORNING...GUIDANCE SUGGESTS WIDESPREAD IFR CEILINGS/VISIBILITIES. ALTHOUGH CERTAINLY POSSIBLE...IT SEEMS UNLIKELY TO BE THAT BAD. CLOUD BASES SHOULD RISE SLOWLY THROUGH THE DAY...AND THERE WILL BE CHANCES OF TSRA ALL DAY...BUT MAINLY IN THE AFTERNOON AND EARLY EVENING. PREV DISCUSSION... /ISSUED 334 PM CDT THU APR 16 2015/ DISCUSSION... THIS DISCUSSION WILL REMAIN FOCUSED ON THE SHORT TERM... THUNDERSTORM AND PRECIPITATION CHANCES FROM THIS EVENING THROUGH FRIDAY MORNING... OVERALL... GUIDANCE HAS DONE A POOR JOB IN HANDLING THE BKN/OVC LOW/MID STRATUS ACROSS THE BULK OF WRN AND CENTRAL OK AND WRN N TX. THROUGH 20Z... SOME SCATTERED CLEARING HAS FINALLY STARTED AS MORE STRATOCU/CLOUD STREETS HAVE DEVELOPED. THIS CLOUD COVER WILL CONTINUE TO PROMOTE A LACK OF INSTABILITY/BL MIXING ACROSS MOST OF WRN OK AND WRN N TX... BUT WITH THE RECENT TRANSITION TO STRATOCU... MIXING MAY FINALLY BE PICKING UP. THE EARLY AFTN CONVECTION ACROSS FAR NW OK AND INTO THE PANHANDLES APPEARED TO BE DRIVEN BY A FOCUSED REGION OF ISENTROPIC ASCENT... SUPPORTED BY A NARROW REGION OF 1500 J/KG INSTABILITY AND DIVERGENCE ALOFT GIVEN THE ORIENTATION OF THE UPPER LVL JET MAX ASSOCIATED WITH THE H500 LOW... WHICH CONTINUES TO SETTLE OVER THE FOUR CORNERS REGION. THE RECENT SEVERE CONVECTION IN THE PANHANDLES THAT DEVELOPED OVER THE PAST 1 TO 2 HOURS IS PRIMARILY FOCUSED ON THE DRYLINE/PSUEDO-FRONTAL BOUNDARY THAT DEVELOPED EARLIER. AT THE MOMENT... HOW CONVECTION WILL EVOLVE THROUGH THIS EVENING REMAINS A CHALLENGE. TRADITIONAL GUIDANCE CONTINUES TO STRUGGLE WITH HOW TO EVOLVE THE UPPER LOW AND CONVECTION. RECENT MESOSCALE GUIDANCE IS ABLE TO CATCH ON IN SPURTS... BUT IT STRUGGLES AS WELL. OVERALL... EXPECT CONVECTION ACROSS THE PANHANDLES TO CONTINUE TO TRANSITION EASTWARD... HOWEVER... RECENT OBS THROUGH 20Z SUGGEST THE DRYLINE MAY BE STARTING ITS GRADUAL RETREAT TO THE WEST. WITH THIS SAID... EXPECT THE SFC TROUGH/FRONT (IF WE CAN CALL IT THAT)... WILL CONTINUE TO LIFT E/NE INTO WRN OK THIS EVENING... WITH STORMS MOVING INTO NWRN OK AROUND 5 TO 7PM CDT. THE OVERALL EVOLUTION OF STORMS APPEAR TO HAVE BEEN CAPTURED ON THE RECENT HRRR (18Z RUN)... BUT THE TIMING MAY BE LATE... THE 12Z TTU WRF SEEMS TO HAVE A DECENT HANDLE ON TIMING... AS DOES THE WRF-NMM. NOT TO FOCUS SOLELY ON THE WRN ACTIVITY... STRONG CONVECTION HAS DEVELOPED ACROSS WEST CENTRAL TX THIS AFTN. CURRENT THOUGHTS HAVE THIS ACTIVITY LIFTING N/NE INTO WRN N TX AND THE RED RIVER VALLEY. RECENT MESOSCALE GUIDANCE SEEMS TO SUGGEST THIS ACTIVITY WILL LESSEN AFTER SUNSET AS IT REMAINS DRIVEN BY DIURNAL HEATING/INSTABILITY. AS FOR SEVERE STORMS THIS AFTN/EVENING ACROSS WRN OK/WRN N TX... STORMS THAT ARE ABLE TO MOVE IN OR DEVELOP WILL RESIDE WITHIN AN ENVIRONMENT SUPPORTIVE OF LARGE HAIL (GOLF BALLS) AND DAMAGING WINDS (60-70MPH). SEVERE POTENTIAL WILL WANE WITH ANY SCATTERED CONVECTION THAT PERSISTS INTO THE OVERNIGHT HOURS EASTWARD INTO CENTRAL OK BY FRIDAY MORNING. THE TORNADO THREAT OVER THE TX PANHANDLE WILL DIMINISH AS STORMS MOVE OFF THE DRYLINE AND INTO WRN OK... 0-1KM HELICITY DECREASES AND THE LACK OF A FOCUSING BOUNDARY DOES NOT BODE WELL FOR TORNADIC DEVELOPMENT ACROSS WRN OK AT THE MOMENT. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 59 74 59 77 / 40 50 60 30 HOBART OK 57 75 55 77 / 60 50 50 20 WICHITA FALLS TX 60 77 58 80 / 40 50 50 20 GAGE OK 54 74 51 76 / 90 50 50 20 PONCA CITY OK 58 74 58 75 / 40 60 70 50 DURANT OK 61 77 62 78 / 30 50 60 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 03/23/23
AREA FORECAST DISCUSSION
NWS NORMAN OK
924 PM CDT THU APR 16 2015 .DISCUSSION... A COMPLEX OF THUNDERSTORMS HAD DEVELOPED OVER NORTHWEST OKLAHOMA BY LATE THIS EVENING. A WAKE LOW APPEARS TO BE DEVELOPING WITHIN THE COMPLEX...LEADING TO RATHER STRONG WINDS IN ELLIS COUNTY. THESE WINDS MAY EXPAND OR CONTINUE TO SHIFT TO THE SOUTH WITH TIME. THEY ARE TOO SMALL-SCALE TO REPRESENT IN A REASONABLE WAY IN THE FORECAST. SHORT-RANGE MODELS SHOW A GENERAL TENDENCY OF THE EXISTING STORM COMPLEX TO START SHIFTING EAST WITH TIME...REACHING CENTRAL AND/OR NORTH-CENTRAL OKLAHOMA SEVERAL HOURS AFTER MIDNIGHT. DETAILS REMAIN SKETCHY...BUT THE OVERALL CONCEPT IS CONSISTENT AND IS REASONABLE...GIVEN THE CURRENT SITUATION. THE FORECAST WAS UPDATED EARLIER TO ACCOUNT FOR RAIN TRENDS AND THEIR LARGE-SCALE EFFECTS. WE WILL CONTINUE TO UPDATE AS NEEDED TO KEEP UP-TO-DATE WITH THE STORM SYSTEM AS IT EVOLVES TONIGHT. && .PREV DISCUSSION... /ISSUED 626 PM CDT THU APR 16 2015/ DISCUSSION... THE 00Z AVIATION DISCUSSION FOLLOWS.... AVIATION... SCT TSRA...A FEW STRONG/SEVERE...WILL OCCUR OVER W OK/N TX W/KSPS THIS EVENING. TAFS MENTION TSRA ONLY WHERE PROBABILITY IS GREATER THAN 50 PERCENT THIS EVENING. A SMALL STORM COMPLEX MAY FORM AROUND MIDNIGHT FROM EXISTING STORMS...AND SPEED E ALONG THE KS/OK BORDER. IF THIS HAPPENS...STRONG W WINDS WILL OCCUR AT KPNC. THE KPNC TAF INCLUDES THIS EVENT...BUT NOT AS STRONG AS IT MIGHT BE. TOMORROW MORNING...GUIDANCE SUGGESTS WIDESPREAD IFR CEILINGS/VISIBILITIES. ALTHOUGH CERTAINLY POSSIBLE...IT SEEMS UNLIKELY TO BE THAT BAD. CLOUD BASES SHOULD RISE SLOWLY THROUGH THE DAY...AND THERE WILL BE CHANCES OF TSRA ALL DAY...BUT MAINLY IN THE AFTERNOON AND EARLY EVENING. PREV DISCUSSION... /ISSUED 334 PM CDT THU APR 16 2015/ DISCUSSION... THIS DISCUSSION WILL REMAIN FOCUSED ON THE SHORT TERM... THUNDERSTORM AND PRECIPITATION CHANCES FROM THIS EVENING THROUGH FRIDAY MORNING... OVERALL... GUIDANCE HAS DONE A POOR JOB IN HANDLING THE BKN/OVC LOW/MID STRATUS ACROSS THE BULK OF WRN AND CENTRAL OK AND WRN N TX. THROUGH 20Z... SOME SCATTERED CLEARING HAS FINALLY STARTED AS MORE STRATOCU/CLOUD STREETS HAVE DEVELOPED. THIS CLOUD COVER WILL CONTINUE TO PROMOTE A LACK OF INSTABILITY/BL MIXING ACROSS MOST OF WRN OK AND WRN N TX... BUT WITH THE RECENT TRANSITION TO STRATOCU... MIXING MAY FINALLY BE PICKING UP. THE EARLY AFTN CONVECTION ACROSS FAR NW OK AND INTO THE PANHANDLES APPEARED TO BE DRIVEN BY A FOCUSED REGION OF ISENTROPIC ASCENT... SUPPORTED BY A NARROW REGION OF 1500 J/KG INSTABILITY AND DIVERGENCE ALOFT GIVEN THE ORIENTATION OF THE UPPER LVL JET MAX ASSOCIATED WITH THE H500 LOW... WHICH CONTINUES TO SETTLE OVER THE FOUR CORNERS REGION. THE RECENT SEVERE CONVECTION IN THE PANHANDLES THAT DEVELOPED OVER THE PAST 1 TO 2 HOURS IS PRIMARILY FOCUSED ON THE DRYLINE/PSUEDO-FRONTAL BOUNDARY THAT DEVELOPED EARLIER. AT THE MOMENT... HOW CONVECTION WILL EVOLVE THROUGH THIS EVENING REMAINS A CHALLENGE. TRADITIONAL GUIDANCE CONTINUES TO STRUGGLE WITH HOW TO EVOLVE THE UPPER LOW AND CONVECTION. RECENT MESOSCALE GUIDANCE IS ABLE TO CATCH ON IN SPURTS... BUT IT STRUGGLES AS WELL. OVERALL... EXPECT CONVECTION ACROSS THE PANHANDLES TO CONTINUE TO TRANSITION EASTWARD... HOWEVER... RECENT OBS THROUGH 20Z SUGGEST THE DRYLINE MAY BE STARTING ITS GRADUAL RETREAT TO THE WEST. WITH THIS SAID... EXPECT THE SFC TROUGH/FRONT (IF WE CAN CALL IT THAT)... WILL CONTINUE TO LIFT E/NE INTO WRN OK THIS EVENING... WITH STORMS MOVING INTO NWRN OK AROUND 5 TO 7PM CDT. THE OVERALL EVOLUTION OF STORMS APPEAR TO HAVE BEEN CAPTURED ON THE RECENT HRRR (18Z RUN)... BUT THE TIMING MAY BE LATE... THE 12Z TTU WRF SEEMS TO HAVE A DECENT HANDLE ON TIMING... AS DOES THE WRF-NMM. NOT TO FOCUS SOLELY ON THE WRN ACTIVITY... STRONG CONVECTION HAS DEVELOPED ACROSS WEST CENTRAL TX THIS AFTN. CURRENT THOUGHTS HAVE THIS ACTIVITY LIFTING N/NE INTO WRN N TX AND THE RED RIVER VALLEY. RECENT MESOSCALE GUIDANCE SEEMS TO SUGGEST THIS ACTIVITY WILL LESSEN AFTER SUNSET AS IT REMAINS DRIVEN BY DIURNAL HEATING/INSTABILITY. AS FOR SEVERE STORMS THIS AFTN/EVENING ACROSS WRN OK/WRN N TX... STORMS THAT ARE ABLE TO MOVE IN OR DEVELOP WILL RESIDE WITHIN AN ENVIRONMENT SUPPORTIVE OF LARGE HAIL (GOLF BALLS) AND DAMAGING WINDS (60-70MPH). SEVERE POTENTIAL WILL WANE WITH ANY SCATTERED CONVECTION THAT PERSISTS INTO THE OVERNIGHT HOURS EASTWARD INTO CENTRAL OK BY FRIDAY MORNING. THE TORNADO THREAT OVER THE TX PANHANDLE WILL DIMINISH AS STORMS MOVE OFF THE DRYLINE AND INTO WRN OK... 0-1KM HELICITY DECREASES AND THE LACK OF A FOCUSING BOUNDARY DOES NOT BODE WELL FOR TORNADIC DEVELOPMENT ACROSS WRN OK AT THE MOMENT. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 59 74 59 77 / 40 50 60 30 HOBART OK 57 75 55 77 / 60 50 50 20 WICHITA FALLS TX 60 77 58 80 / 40 50 50 20 GAGE OK 54 74 51 76 / 90 50 50 20 PONCA CITY OK 58 74 58 75 / 40 60 70 50 DURANT OK 61 77 62 78 / 30 50 60 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 23/03
AREA FORECAST DISCUSSION
NWS NORMAN OK
626 PM CDT THU APR 16 2015 .DISCUSSION... THE 00Z AVIATION DISCUSSION FOLLOWS.... && .AVIATION... SCT TSRA...A FEW STRONG/SEVERE...WILL OCCUR OVER W OK/N TX W/KSPS THIS EVENING. TAFS MENTION TSRA ONLY WHERE PROBABILITY IS GREATER THAN 50 PERCENT THIS EVENING. A SMALL STORM COMPLEX MAY FORM AROUND MIDNIGHT FROM EXISTING STORMS...AND SPEED E ALONG THE KS/OK BORDER. IF THIS HAPPENS...STRONG W WINDS WILL OCCUR AT KPNC. THE KPNC TAF INCLUDES THIS EVENT...BUT NOT AS STRONG AS IT MIGHT BE. TOMORROW MORNING...GUIDANCE SUGGESTS WIDESPREAD IFR CEILINGS/VISIBILITIES. ALTHOUGH CERTAINLY POSSIBLE...IT SEEMS UNLIKELY TO BE THAT BAD. CLOUD BASES SHOULD RISE SLOWLY THROUGH THE DAY...AND THERE WILL BE CHANCES OF TSRA ALL DAY...BUT MAINLY IN THE AFTERNOON AND EARLY EVENING. && .PREV DISCUSSION... /ISSUED 334 PM CDT THU APR 16 2015/ DISCUSSION... THIS DISCUSSION WILL REMAIN FOCUSED ON THE SHORT TERM... THUNDERSTORM AND PRECIPITATION CHANCES FROM THIS EVENING THROUGH FRIDAY MORNING... OVERALL... GUIDANCE HAS DONE A POOR JOB IN HANDLING THE BKN/OVC LOW/MID STRATUS ACROSS THE BULK OF WRN AND CENTRAL OK AND WRN N TX. THROUGH 20Z... SOME SCATTERED CLEARING HAS FINALLY STARTED AS MORE STRATOCU/CLOUD STREETS HAVE DEVELOPED. THIS CLOUD COVER WILL CONTINUE TO PROMOTE A LACK OF INSTABILITY/BL MIXING ACROSS MOST OF WRN OK AND WRN N TX... BUT WITH THE RECENT TRANSITION TO STRATOCU... MIXING MAY FINALLY BE PICKING UP. THE EARLY AFTN CONVECTION ACROSS FAR NW OK AND INTO THE PANHANDLES APPEARED TO BE DRIVEN BY A FOCUSED REGION OF ISENTROPIC ASCENT... SUPPORTED BY A NARROW REGION OF 1500 J/KG INSTABILITY AND DIVERGENCE ALOFT GIVEN THE ORIENTATION OF THE UPPER LVL JET MAX ASSOCIATED WITH THE H500 LOW... WHICH CONTINUES TO SETTLE OVER THE FOUR CORNERS REGION. THE RECENT SEVERE CONVECTION IN THE PANHANDLES THAT DEVELOPED OVER THE PAST 1 TO 2 HOURS IS PRIMARILY FOCUSED ON THE DRYLINE/PSUEDO-FRONTAL BOUNDARY THAT DEVELOPED EARLIER. AT THE MOMENT... HOW CONVECTION WILL EVOLVE THROUGH THIS EVENING REMAINS A CHALLENGE. TRADITIONAL GUIDANCE CONTINUES TO STRUGGLE WITH HOW TO EVOLVE THE UPPER LOW AND CONVECTION. RECENT MESOSCALE GUIDANCE IS ABLE TO CATCH ON IN SPURTS... BUT IT STRUGGLES AS WELL. OVERALL... EXPECT CONVECTION ACROSS THE PANHANDLES TO CONTINUE TO TRANSITION EASTWARD... HOWEVER... RECENT OBS THROUGH 20Z SUGGEST THE DRYLINE MAY BE STARTING ITS GRADUAL RETREAT TO THE WEST. WITH THIS SAID... EXPECT THE SFC TROUGH/FRONT (IF WE CAN CALL IT THAT)... WILL CONTINUE TO LIFT E/NE INTO WRN OK THIS EVENING... WITH STORMS MOVING INTO NWRN OK AROUND 5 TO 7PM CDT. THE OVERALL EVOLUTION OF STORMS APPEAR TO HAVE BEEN CAPTURED ON THE RECENT HRRR (18Z RUN)... BUT THE TIMING MAY BE LATE... THE 12Z TTU WRF SEEMS TO HAVE A DECENT HANDLE ON TIMING... AS DOES THE WRF-NMM. NOT TO FOCUS SOLELY ON THE WRN ACTIVITY... STRONG CONVECTION HAS DEVELOPED ACROSS WEST CENTRAL TX THIS AFTN. CURRENT THOUGHTS HAVE THIS ACTIVITY LIFTING N/NE INTO WRN N TX AND THE RED RIVER VALLEY. RECENT MESOSCALE GUIDANCE SEEMS TO SUGGEST THIS ACTIVITY WILL LESSEN AFTER SUNSET AS IT REMAINS DRIVEN BY DIURNAL HEATING/INSTABILITY. AS FOR SEVERE STORMS THIS AFTN/EVENING ACROSS WRN OK/WRN N TX... STORMS THAT ARE ABLE TO MOVE IN OR DEVELOP WILL RESIDE WITHIN AN ENVIRONMENT SUPPORTIVE OF LARGE HAIL (GOLF BALLS) AND DAMAGING WINDS (60-70MPH). SEVERE POTENTIAL WILL WANE WITH ANY SCATTERED CONVECTION THAT PERSISTS INTO THE OVERNIGHT HOURS EASTWARD INTO CENTRAL OK BY FRIDAY MORNING. THE TORNADO THREAT OVER THE TX PANHANDLE WILL DIMINISH AS STORMS MOVE OFF THE DRYLINE AND INTO WRN OK... 0-1KM HELICITY DECREASES AND THE LACK OF A FOCUSING BOUNDARY DOES NOT BODE WELL FOR TORNADIC DEVELOPMENT ACROSS WRN OK AT THE MOMENT. JTK && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 59 74 59 77 / 40 50 60 30 HOBART OK 57 75 55 77 / 50 50 50 20 WICHITA FALLS TX 60 77 58 80 / 40 50 50 20 GAGE OK 54 74 51 76 / 70 50 50 20 PONCA CITY OK 58 74 58 75 / 30 60 70 50 DURANT OK 61 77 62 78 / 30 50 60 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 03/23/23
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
822 PM CDT THU APR 16 2015 .DISCUSSION... RADAR IS PRECIP FREE AT THIS TIME BUT CLOUDINESS STILL BLANKETS MUCH OF THE AREA. MOISTURE IN THE FORM OF SHOWERS AND THUNDERSTORMS DOES EXIST TO OUR SOUTH AND SOUTHWEST ACROSS MS AND AL. LATEST HRRR DOES INDICATE THAT SOME OF THIS MOISTURE MAY APPROACH OUR SOUTHWESTERN AREAS TOWARD 12Z. UPPER LEVEL PATTERN CONTINUES TO FLOW FROM THE SOUTHWEST. WE ARE EXPECTING SOME AMPLIFICATION OF A SE-NW UPPER RIDGE BY TOMORROW, BEFORE THAT HAPPENS HOWEVER...ONE MORE WEAK DISTURBANCE WILL RIDE NORTHEASTWARD AND JUST ENOUGH UPPER DIVERGENCE MAY HELP PRODUCE THAT AFOREMENTIONED ACTIVITY TOWARD 12Z. OTW...DEWPOINT DEPRESSIONS ARE VERY LOW CURRENTLY. NUMERICAL DATA DOES SUGGEST SOME LOW VSBY CATS. THUS...WILL GO AHEAD AND ADD PATCHY FOG AREA WIDE FOR AFT 06Z. ADDITIONALLY...WILL OPT TO LOWER POPS TO 20 PERCENT FOR THE ENTIRE MID STATE EXCEPT FOR OUR SOUTHWEST...WHERE POPS WILL REMAIN AT 30 PERCENT. JUST SHOWERS TONIGHT...NO T EXPECTED. && .PREV DISCUSSION... /ISSUED 652 PM CDT THU APR 16 2015/ UPDATE...FOR 00Z AVIATION DISCUSSION. AVIATION...00Z AVIATION DISCUSSION. SEVERAL ADMS POSSIBLE THRU 17/24Z DUE TO CEILING FORMATION/FLUCTUATIONS AND FOG FORMATION POTENTIALLY LIMITING VSBYS. UPPER LEVEL RIDGING INFLUENCES SHOULD AMPLIFY THRU 17/24Z ALSO AND SHOULD LIMIT CONVECTION POTENTIAL AT TAF SITES...AS SHORT RANGE MODELS SHOWING LITTLE IN THE WAY OF CONVECTION THRU 17/12Z. EXPECT MVFR CEILINGS BNA AND CSV TO PERSIST THRU AT LEAST 17/15Z. WITH MOISTURE RICH AIRMASS GENERALLY IN PLACE...BELIEVE THAT THERE MAYBE ENOUGH CLRING...ESPECIALLY ACROSS CNTRL/NW PORTIONS OF THE MID STATE...WITH LIGHT WINDS FOR PATCHY FOG DEVELOPMENT...FOR MVFR TO IFR FOG POSSIBLE...WITH TEMPO LIFR VSBYS POSSIBLE BNA/CSV. EXPECT FOG DISSIPATION AFTER 17/15Z WITH DISSIPATION IN MVFR/IFR CEILINGS AFTER 17/18Z...BUT FOR TAF BREVITY CONCERNS... DID NOT MENTION IN TAF FORECAST AS THIS TIME. PREV DISCUSSION.../ISSUED 318 PM CDT THU APR 16 2015/ SHORT TERM...SKIES REMAINED MOSTLY CLOUDY INTO THE EARLY AFTERNOON OVER EASTERN AND SOUTHERN PARTS OF THE MID-STATE. MEANWHILE, SKIES BECAME PARTLY CLOUDY OVER THE WEST. AS USUAL FOR THIS TIME OF YEAR, TEMPS WERE QUICK TO WARM UP ONCE THE SUN POPPED OUT AND AT 2 PM, CLARKSVILLE WAS EXPERIENCING A TOASTY 74 DEGREES. TEMPERATURES WERE STRUGGLING A BIT MORE IN THE MOSTLY CLOUDY AREAS, WITH 2 PM READINGS MAINLY IN THE MIDDLE AND UPPER 60S OVER EASTERN AND CENTRAL AREAS. THE SHORTWAVE THAT BROUGHT US THE ROUND OF SHOWERS AND THUNDERSTORMS LAST NIGHT AND THIS MORNING, WAS CROSSING THE OHIO VALLEY THIS AFTERNOON AND PUSHING MOST THE SHOWERS AND THUNDERSTORMS TO THE EAST OF OUR FORECAST AREA. HOWEVER, SINCE THE UPPER LEVEL DISTURBANCE WAS PASSING SO FAR TO OUR NORTH, A BAND OF RELATIVELY DEEP MOISTURE WAS SLOW TO PUSH OUT OF OUR EASTERN AND SOUTHERN COUNTIES. AS A RESULT, BY EARLY AFTERNOON SOME SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS REMAINED ALONG THE CUMBERLAND PLATEAU AND IN AREAS CLOSE TO THE ALABAMA BORDER. IT STILL LOOKS LIKE WE`LL GET A TEMPORARY BREAK TONIGHT THROUGH SATURDAY MORNING FROM THE MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY THAT WE`VE SEEN OVER RECENT DAYS. IN ADDITION, AS CLOUDS DIMINISH FRIDAY NIGHT, BELIEVE OUR SOGGY WET GROUND WILL AID THE DEVELOPMENT OF AREAS OF FOG--SOME OF WHICH COULD BECOME LOCALLY DENSE. ANOTHER SWATH OF DEEP MOISTURE SWINGS NORTHEASTWARD ACROSS THE AREA SATURDAY AFTERNOON AND SATURDAY NIGHT, BRINGING ANOTHER ROUND OF SHOWERS AND STORMS AND THE POTENTIAL FOR LOCALLY HEAVY RAINFALL. SINCE THE RESPONSIBLE SHORTWAVE SHEARS OFF ONCE AGAIN TO THE NORTH, THE RAIN IS SLOWER TO CLEAR OUT OF OUR EASTERN AREAS, AND THE CUMBERLAND PLATEAU COULD SEE SHOWERS AND THUNDERSTORMS FOR A GOOD PART OF SUNDAY AS WELL. ANOTHER INCH OR SO OF RAIN WILL LIKELY OCCUR, SOME OF WHICH WILL COME IN DOWNPOURS. SINCE GROUNDS WILL SILL BE PRETTY SOGGY BY THEN, EXPECT RUN OFF TO PRODUCE PONDING OF WATER IN URBAN LOCATIONS (LIKE NASHVILLE) AND IN LOW LYING AREAS. AFTER THE RAIN PASSES EAST OF OUR AREA SUNDAY EVENING, LOOK FOR A COLD FRONT TO SWEEP ACROSS THE AREA SUNDAY NIGHT AND MONDAY MORNING, BRINGING ANOTHER ROUND OF RAIN. THIS WILL PROBABLY COME ACROSS THE AREA AS A RELATIVELY FAST-MOVING BAND OF SHOWERS AND THUNDERSTORMS, AND BRIEF HEAVY DOWNPOURS MAY ONCE AGAIN OCCUR, AND CAUSE SOME PONDING IN LOW LYING SPOTS AND URBAN AREAS. HOWEVER, THE STORMS AND SHOWERS SHOULDN`T LAST LONG, AND BY MONDAY AFTERNOON WE SHOULD BE DRYING OUT PRETTY WELL, AS HIGH PRESSURE BUILDS IN FROM THE WEST. LONG TERM...A DRY SHORTWAVE SWINGS IN MONDAY NIGHT, DEEPENING AN UPPER LEVEL TROUGH OVER THE GREAT LAKES AND TENNESSEE VALLEY. SOME PATCHY CLOUDS WILL SPREAD ACROSS THE AREA, BUT DON`T EXPECT ANYTHING MORE THAN SOME LIGHT SPRINKLES. BY SUNRISE TUESDAY, COOLER AIR WILL HAVE WORKED IN FROM THE NORTHWEST AND WE`LL BE LOOKING AT TEMPERATURES IN THE MIDDLE AND UPPER 40S. DRY AND COOL WEATHER LINGERS INTO WEDNESDAY, WITH LOWS IN THE 40S AND HIGHS FROM THE MID 60S TO MID 70S. ATMOSPHERIC MOISTURE INCREASES AGAIN BY LATE NEXT WEEK, CREATING THE CHANCE FOR MORE SHOWERS AND THUNDERSTORMS. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 60 79 59 80 / 20 20 20 30 CLARKSVILLE 60 77 60 78 / 20 20 20 30 CROSSVILLE 56 71 56 74 / 20 30 20 20 COLUMBIA 59 77 59 79 / 20 30 20 50 LAWRENCEBURG 59 75 60 77 / 30 30 20 60 WAVERLY 61 79 60 77 / 20 20 20 50 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
953 PM CDT THU APR 16 2015 .UPDATE... VERY BUSY EVENING AS ADVERTISED. CATEGORICAL POPS IN ORDER THROUGH MID NIGHT AREA WIDE...OUTSIDE OF THE COAST/SWRN COUNTIES BEHIND MAIN AREA OF CONVECTION. LATEST MESO ANALYSIS INDICATES PRIMARY/EFFECTIVE WARM FRONT ESTABLISHED ROUGHLY ALONG AND JUST SOUTH OF I-10 WITH ABUNDANT MOISTURE /SURFACE DEWPOINTS IN THE LOWER 70S/ IN PLACE ACROSS THE WARM SECTOR. SPC HAS TORNADO WATCH IN EFFECT AS ACTIVITY NEAR AND SOUTH OF THIS FRONT INGESTS MODERATELY UNSTABLE AND WEAKLY CAPPED WARM SECTOR AIR. THIS WILL INCREASE THE POTENTIAL FOR SPIN UPS UNTIL THE WARM SECTOR ITSELF BEGINS TO CAP OFF LATER TONIGHT. IMPRESSIVE FEED OF MOISTURE WILL SUSTAIN THREAT OF HEAVY RAIN WITH ANY ACTIVITY AREA WIDE. CURRENTLY FFA IS CONFINED TO THE WARM SECTOR WHERE MOST ABUNDANT FEED OF MOISTURE SHOULD CONFINE THE MOST INTENSE RAINFALL RATES. HOWEVER FLOODING REMAINS A CONCERN AREA WIDE GIVEN THE EVENING RAINFALL ACROSS SOME NRN AREAS. THUS...FEEL FFA IS WARRANTED ACROSS THE CWA THROUGH THE DAY TOMORROW AND WILL EXPAND. WITH ANOTHER POSSIBLE LATE DAY/EVENING MCS...FFA MAY NEED TO BE EXTENDED IN LATER FORECASTS THROUGH THE NIGHT FRIDAY/SATURDAY MORNING. && .PREV DISCUSSION... /ISSUED 659 PM CDT THU APR 16 2015/ DISCUSSION... 00Z TAF DISCUSSION IN AVIATION... AVIATION... MAIN CONCERN IS OBVIOUSLY CONVECTION. LOOKS LIKE CONVECTION WILL BE ENDING THROUGH 02-03Z...WILL HOLD ONTO VCTS/TSRA FOR MOST TAF SITES AS CONVECTION WANES. BASED ON HRRR TRENDS MAY KEEP SOME VCSH GOING THROUGH THE NIGHT IF ANYTHING RE-DEVELOPS. CONFIDENCE IS NOT VERY HIGH ON THIS SO ANTICIPATE AMMENDING TAFS TO REMOVE CONVECTION IN THE SHORT TERM. CIGS SHOULD BE VFR/MVFR OVERNIGHT INTO TOMORROW MORNING. BASED ON WRF-ARW/TX TECH WRF AND EVEN SUPPORTED BY GFS...EXPECT LARGE MCS TO MOVE INTO THE AREA IN THE EVENING SO ADDED MENTION OF VCTS FOR TAFS. STILL TIME TO WORK OUT THESE DETAILS AND LIKELY BE FOCUS OF 06Z TAFS. 39 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 66 78 66 79 63 / 90 70 60 50 40 HOUSTON (IAH) 68 79 67 80 64 / 90 70 60 50 40 GALVESTON (GLS) 70 77 70 76 69 / 70 60 60 50 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. GM...NONE. && $$ DISCUSSION...48
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
947 PM CDT THU APR 16 2015 .UPDATE... VERY BUSY EVENING AS ADVERTISED. CATEGORICAL POPS IN ORDER THROUGH MID NIGHT AREA WIDE...OUTSIDE OF THE COAST/SWRN COUNTIES BEHIND MAIN AREA OF CONVECTION. LATEST MESO ANALYSIS INDICATES PRIMARY/EFFECTIVE WARM FRONT ESTABLISHED ROUGHLY ALONG AND JUST SOUTH OF I-10 WITH ABUNDANT MOISTURE /SURFACE DEWPOINTS IN THE LOWER 70S/ IN PLACE ACROSS THE WARM SECTOR. SPC HAS TORNADO WATCH IN EFFECT AS ACTIVITY NEAR AND SOUTH OF THIS FRONT INGESTS MODERATELY UNSTABLE AND WEAKLY CAPPED WARM SECTOR AIR. THIS WILL INCREASE THE POTENTIAL FOR SPIN UPS UNTIL THE WARM SECTOR ITSELF BEGINS TO CAP OFF LATER TONIGHT. IMPRESSIVE FEED OF MOISTURE WILL SUSTAIN THREAT OF HEAVY RAIN WITH ANY ACTIVITY AREA WIDE. CURRENTLY FFW IS CONFINED TO THE WARM SECTOR WHERE MOST ABUNDANT FEED OF MOISTURE SHOULD CONFINE THE MOST INTENSE RAINFALL RATES. HOWEVER FLOODING REMAINS A CONCERN AREA WIDE GIVEN THE EVENING RAINFALL ACROSS SOME NRN AREAS. THUS...FEEL FFW IS WARRANTED ACROSS THE CWA THROUGH THE DAY TOMORROW AND WILL EXPAND. WITH ANOTHER POSSIBLE LATE DAY/EVENING MCS...FFW MAY NEED TO BE EXTENDED IN LATER FORECASTS THROUGH THE NIGHT FRIDAY/SATURDAY MORNING. && .PREV DISCUSSION... /ISSUED 659 PM CDT THU APR 16 2015/ DISCUSSION... 00Z TAF DISCUSSION IN AVIATION... AVIATION... MAIN CONCERN IS OBVIOUSLY CONVECTION. LOOKS LIKE CONVECTION WILL BE ENDING THROUGH 02-03Z...WILL HOLD ONTO VCTS/TSRA FOR MOST TAF SITES AS CONVECTION WANES. BASED ON HRRR TRENDS MAY KEEP SOME VCSH GOING THROUGH THE NIGHT IF ANYTHING RE-DEVELOPS. CONFIDENCE IS NOT VERY HIGH ON THIS SO ANTICIPATE AMMENDING TAFS TO REMOVE CONVECTION IN THE SHORT TERM. CIGS SHOULD BE VFR/MVFR OVERNIGHT INTO TOMORROW MORNING. BASED ON WRF-ARW/TX TECH WRF AND EVEN SUPPORTED BY GFS...EXPECT LARGE MCS TO MOVE INTO THE AREA IN THE EVENING SO ADDED MENTION OF VCTS FOR TAFS. STILL TIME TO WORK OUT THESE DETAILS AND LIKELY BE FOCUS OF 06Z TAFS. 39 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. GM...NONE. && $$ DISCUSSION...48
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
659 PM CDT THU APR 16 2015 .DISCUSSION... 00Z TAF DISCUSSION IN AVIATION... && .AVIATION... MAIN CONCERN IS OBVIOUSLY CONVECTION. LOOKS LIKE CONVECTION WILL BE ENDING THROUGH 02-03Z...WILL HOLD ONTO VCTS/TSRA FOR MOST TAF SITES AS CONVECTION WANES. BASED ON HRRR TRENDS MAY KEEP SOME VCSH GOING THROUGH THE NIGHT IF ANYTHING RE-DEVELOPS. CONFIDENCE IS NOT VERY HIGH ON THIS SO ANTICIPATE AMMENDING TAFS TO REMOVE CONVECTION IN THE SHORT TERM. CIGS SHOULD BE VFR/MVFR OVERNIGHT INTO TOMORROW MORNING. BASED ON WRF-ARW/TX TECH WRF AND EVEN SUPPORTED BY GFS...EXPECT LARGE MCS TO MOVE INTO THE AREA IN THE EVENING SO ADDED MENTION OF VCTS FOR TAFS. STILL TIME TO WORK OUT THESE DETAILS AND LIKELY BE FOCUS OF 06Z TAFS. 39 && .PREV DISCUSSION... /ISSUED 357 PM CDT THU APR 16 2015/ DISCUSSION... AN ACTIVE DAY WITH THE MAIN WEATHER ELEMENTS BEING OF EARLY AFTERNOON HAIL OVER WEST HOUSTON FROM QUICKER PULSERS TRANSITIONING TO TRAINING HEAVY RAINS LEADING GREATER THAN 4 INCH AMOUNTS OVER THE SOUTHEASTERN CWA (EASTERN LIBERTY AND CHAMBERS COUNTIES). THE NEXT ROUND OF THUNDERSTORM CLUSTERS ARE NOW BEGINNING TO IMPACT THE WESTERN FORECAST AREA...WITH THOSE COMMUNITIES ALONG AND NORTH OF HIGHWAY 59 TARGETED IN THE SHORT TERM FOR EXCESSIVE RAINFALL LEADING TO FLASH FLOODING. THE MONSTER STORM OVER REFUGIO COUNTY WAS A RIGHT TURNER AND PRODUCED A TORNADO ABOUT AN HOUR AGO SO... ANY STRONG CELL THAT BEGINS TO EXHIBIT THIS TURNING BEHAVIOR (WITH THE BACKGROUND AS UNSTABLE AND SHEARED AS PREVIOUSLY ADVERTISED) WILL LIKELY BECOME SEVERE. HENCE...THE MAIN THREAT WILL BE FLASH FLOODING WITH THE SECONDARY THREATS BEING THAT OF TORNADOES OR LARGE HAIL WITHIN THESE DISCREET CELLS. ANTICIPATING CONTINUED RAINFALL TO EITHER FOCUS NORTH OR SOUTH... THAT MAY BE A LOW SKILL STATEMENT BUT IT COULD EASILY VERIFY. NORTHERN RAIN FROM CENTRAL TEXAS CELLS MOVING INTO A NON-WORKED OVER AIR MASS WITH SOUTHERN CWA ACTIVITY FOCUSED ALONG EITHER THE WARM FRONT OR OLDER OUTFLOW BOUNDARIES FROM THIS AFTERNOON`S CONVECTION. EITHER WAY...THE ABOVE THREATS WILL BE ONGOING THROUGH AT LEAST SATURDAY MORNING. AS THE FOUR CORNERS CENTERED UPPER LOW SLOWLY ROTATES EASTWARD THROUGH THE WEEKEND...EASTERN TEXAS WILL REMAIN UNDER THE BEST UPPER LEVEL DIVERGENCE WITH A VICINITY JET SPEED MAX AIDING IN MID-UPPER EXHAUST. INSPECTION OF W/V IMAGERY AND NPW PROGS DEPICT ANOTHER COUPLE LOBES OF HIGHER PV MOVING UP WITHIN THE SW STEERING FLOW TOMORROW. AFTER AN EARLY (FRI)DAY OF SCATTERED MORE DISCREET CELLULAR FORMATION...MODELS ARE LATCHING ONTO POSSIBLY A WESTERN AREA MCS THAT WILL MOVE ACROSS THE CWA TOMORROW AFTERNOON. IF THIS OCCURS...THEN EXPECT ANOTHER DECENT ROUND OF GREATER THAN ONE OR TWO INCH RAIN AMOUNTS (LEADING TO FLASH FLOODING)...HIGH WINDS...HAIL...AND MAYBE THAT ISOLATED TORNADO/FUNNEL. THIS HIGHLY MOIST NON-CAPPED AIR MASS THAT DISPLAYS AMPLE SHEAR INDICES WILL WARRANT THE MENTION OF ALL OF THE ELEMENTS USUALLY ASSOCIATED WITH SEVERE DISCRETE OR MULTI- CELLULAR STORM STRUCTURE(S). THE 5H TROUGH AXIS SWINGS EAST OF TEXAS BY SUNDAY PM...AFFORDING THE AREA A MUCH NEEDED EARLY WEEK BREAK. WEAK WESTERN DISTURBANCES WILL RIDING ON THROUGH WITHIN THE NEAR-ZONAL FLOW WILL KEEP SLIGHT TO LOW CHANCE POPS IN PLACE FOR MORE SHORT LIVED WARMTH-OF-THE-DAY -TSRA. A EVOLVING SOUTHERN CALI/BAJA UPPER LOW WILL AGAIN BACK WINDS TO MORE SOUTHWESTERLY GOING INTO MID-WEEK. A LEAD SHORTWAVE PASSING INTO TEXAS WEDNESDAY WILL INCREASE POPS BACK TO MODERATE. OVERCAST THROUGH MONDAY THEN PARTLY CLOUDY UNTIL MID WEEK AS CLOUDS FILL BACK IN. AVERAGE AFTERNOONS IN THE LOW TO MID 80S/MID TO UPPER 70S ON THOSE DAYS OF HIGHER PRECIPITATION WITH MINIMUM TEMPERATURES RANGING IN THE MID TO UPPER 60S THE NEXT COUPLE OF DAYS. A EARLY WEEK NORTHERN BOUNDARY PASSAGE WILL USHER IN A SLIGHTLY DRIER AND COOLER AIR MASS THAT WILL HAVE MORNINGS FALLING INTO THE INTERIOR UPPER 50S TO LOWER 60S. 31 MARINE... ONSHORE WINDS WILL PREVAIL THROUGH SUNDAY EVENING AS HIGH PRESSURE REMAINS OVER THE EASTERN GULF OF MEXICO. A BRIEF WIND SHIFT TO THE N-NE IS EXPECTED IN THE WAKE OF THE FRONT. ONSHORE WINDS WIND RETURN MONDAY EVENING AS HIGH PRESSURE AGAIN SHIFTS EAST OF THE REGION. AN EASTERLY FETCH WILL DEVELOP AND PERSIST THROUGH WEDNESDAY EVENING. WOULD EXPECT A SLIGHT INCREASE IN SEAS DUE TO THE PROLONGED FETCH. SOUTHEAST WINDS WILL THEN PREVAIL THROUGH THE END OF THE FORECAST PERIOD. IN THE SHORT TERM...MARINERS SHOULD REMAIN ALERT FOR RAPIDLY CHANGING CONDITIONS TONIGHT AND AGAIN FRIDAY AS A SERIES OF UPPER LEVEL DISTURBANCES MOVE ACROSS THE REGION. SHOWERS AND THUNDERSTORMS WILL DEVELOP AND SOME OF THESE STORMS COULD PRODUCE VERY STRONG WINDS. VISIBILITY WILL ALSO BE REDUCED IN VERY HEAVY RAIN. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 66 78 66 79 63 / 70 70 60 50 40 HOUSTON (IAH) 67 79 67 80 64 / 50 70 60 50 40 GALVESTON (GLS) 71 77 70 76 69 / 40 60 60 50 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...FORT BEND...GALVESTON... HARRIS...JACKSON...LIBERTY...MATAGORDA...WHARTON. GM...NONE. && $$ DISCUSSION...33 AVIATION/MARINE...39
AREA FORECAST DISCUSSION
NWS AMARILLO TX
416 PM CDT WED APR 15 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) NO SURPRISE THE FOCUS OF THE FORECAST IS GOING TO BE CENTERED AROUND THE CLOSED UPPER LEVEL LOW CURRENTLY SLIDING SOUTH ACROSS THE UTAH/COLORADO STATE LINES. THIS AFTERNOON/TONIGHT...A SURFACE TROUGH IS SLOWLY MOVING INTO THE PANHANDLES THIS AFTERNOON AND IS EXPECTED TO HELP CONVECTION DEVELOP. REGIONAL RADAR MOSAIC SHOWS THAT CONVECTION HAS ALREADY BEGUN ACROSS THE SOUTH CENTRAL TEXAS PANHANDLE. RUC FORECAST MUCAPE SHOWS THAT CONVECTION WILL HAVE MARGINAL INSTABILITY ON THE ORDER OF 500-100 J/KG MAINLY ACROSS THE CENTRAL AND NORTHEASTERN PANHANDLES WHERE AS THE SOUTHEASTERN TEXAS PANHANDLES ARE FORECAST FOR 1000-1500 J/KG. A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON GIVEN DEEP LAYER SHEAR WILL BE ROUGHLY 30KT. THE PRIMARY HAZARDS WILL BE HAIL UP TO THE SIZE OF HALF DOLLARS AND DAMAGING WIND GUSTS UP TO 60 MPH. CONVECTIVE CHANCES WILL LING THROUGH THE OVERNIGHT HOURS AND INTO EARLY TOMORROW MORNING HOWEVER THE SEVERE THREAT SHOULD DIMINISH BY 11 PM. THURSDAY...A MORE FAVORABLE ENVIRONMENT FOR SEVERE WEATHER EXIST ACROSS THE PANHANDLES ON THURSDAY. THE CLOSED LOW WILL BE WELL ESTABLISHED OVER THE FOUR CORNERS REGION AND A VORT LOBE ROUNDING THE LOW WILL GIVE A SLIGHT NEGATIVE TILT TO THE PATTERN. THE TIMING OF THIS LOBE IS IN THE GENERAL TIMING OF PEAK HEATING WILL WILL GIVE AMPLE SUPPORT OF CONVECTIVE DEVELOPMENT. SHORT RANGE MODELS ARE HINTING AT AN EARLIER CONVECTIVE INITIATION ACROSS THE WESTERN PANHANDLES BETWEEN 10AM AND NOON TOMORROW WHILE HOLDING OFF SIGNIFICANT DEVELOPMENT UNTIL THE AFTERNOON HOURS. MODELS SHOW THAT STORMS THAT DEVELOP DURING THE AFTERNOON HOURS WILL HAVE 1000-2000 J/KG TO WORK WITH AS DEEP LAYER SHEAR VALUES RANGE FROM 30KT TO 35KT. HODOGRAPHS SUPPORT DISCRETE SUPERCELL DEVELOPMENT BEFORE CONGEALING INTO A LINEAR STRUCTURE DURING THE EVENING HOURS. PWATS THURSDAY AFTERNOON ARE FORECAST TO RANGE BETWEEN 0.95 TO 1.05 INCHES WHICH IS BETWEEN THE CLIMATOLOGICAL +2SD AND THE 99TH PERCENTILE FOR MID APRIL. THIS AMPLE MOISTURE WILL SUPPORT THE POTENTIAL FOR STORMS TO PRODUCE MODERATE TO HEAVY RAINFALL. LARGE HAIL AND DAMAGING WIND WILL BE THE PRIMARY SEVERE WEATHER THREAT WITH AN ISOLATED TORNADO OR TWO BEING POSSIBLE. CONVECTION WILL PUSH OFF INTO WESTERN OKLAHOMA ROUGHLY AROUND 11 PM CDT. 14 .LONG TERM...(FRIDAY THROUGH TUESDAY) A FAIRLY PROGRESSIVE WEATHER PATTERN WILL CONTINUE FRIDAY AS THE UPPER LOW SLOWLY BEGINS MOVING EAST. SINCE THE UPPER LOW WILL BE SITUATED SLIGHTLY FURTHER TO THE EAST COMPARED TO ITS LOCATION ON THURSDAY...AREA OF CONCERN FOR THUNDERSTORM DEVELOPMENT WILL BE ACROSS THE EASTERN PANHANDLES ON FRIDAY. IN FACT...THE GFS SOLUTION IS A LITTLE MORE PROGRESSIVE...SO MUCH OF THE FORECAST AREA ENDS UP BEING DRY SLOTTED FRIDAY MAKING HIGH TEMPERATURES EVEN WARMER. SO QUITE A BIT OF UNCERTAINTY EXISTS CURRENTLY FOR FRIDAY`S CHANCES FOR STORMS. IF STORMS DO DEVELOP...THEY COULD EASILY BE STRONG TO SEVERE WITH HAIL BEING THE BIGGEST THREAT. BY SATURDAY...LOOKS LIKE THE UPPER LOW MOVES JUST NORTH OF THE REGION...WITH ONLY AN ISOLATED CHANCE OF ANY CONVECTION DEVELOPING. AS THIS UPPER LOW FINALLY MOVES WELL TO THE EAST...NORTHWEST FLOW DEVELOPS ALOFT ON SUNDAY. THIS NORTHWEST FLOW WILL HOLD STRONG SUNDAY THROUGH THE MIDDLE OF NEXT WEEK WHICH TRANSLATES TO OFF AND ON PRECIPITATION CHANCES WITH HIGHS IN THE 60S AND LOWER 70S DURING THIS TIME FRAME...QUITE AN UNUSUAL PATTERN FOR MID APRIL OVER THE PANHANDLES. SEVERE WEATHER CHANCES DO NOT LOOK IMPRESSIVE WITH THIS SET UP...IN FACT THINK THUNDERSTORM CHANCES MAY BE HARD TO COME BY AS WELL. BEST CHANCES FOR RAIN WILL CORRESPOND WITH UPPER LEVEL IMPULSES RIDING DOWN THE NORTHWEST FLOW...SO AT THIS POINT IT LOOKS LIKE BOTH MONDAY EVENING AND TUESDAY EVENING SHAPE UP TO HAVE THE BEST RAIN CHANCES. KH && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 50 72 47 71 43 / 40 50 50 20 30 BEAVER OK 51 73 52 73 47 / 40 60 70 40 60 BOISE CITY OK 42 66 42 67 40 / 30 40 50 30 30 BORGER TX 52 73 52 73 47 / 40 50 50 30 30 BOYS RANCH TX 47 75 46 72 42 / 30 40 40 20 20 CANYON TX 49 73 46 72 42 / 40 50 40 20 20 CLARENDON TX 52 73 52 73 49 / 30 60 60 30 40 DALHART TX 44 69 42 69 40 / 30 40 40 20 20 GUYMON OK 48 70 49 71 44 / 30 50 50 30 40 HEREFORD TX 49 74 45 71 41 / 40 40 30 20 20 LIPSCOMB TX 54 74 52 72 49 / 40 60 70 40 60 PAMPA TX 50 71 49 71 46 / 40 60 60 30 40 SHAMROCK TX 54 74 53 74 50 / 30 60 70 40 50 WELLINGTON TX 55 75 52 76 51 / 30 60 60 40 40 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: DALLAM...HARTLEY. OK...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: CIMARRON. && $$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
108 AM CDT WED APR 15 2015 .UPDATE... PLEASE SEE THE 06Z AVIATION DISCUSSION BELOW. && .AVIATION... 11-3.9 SATELLITE IMAGERY SHOWS LOW CLOUDS IN PLACE ALONG THE I-35 CORRIDOR. CLOUD BASES ARE EXPECTED TO LOWER INTO MVFR THROUGH THE EARLY MORNING HOURS AS THE BOUNDARY LAYER CONTINUES TO COOL. VWP FROM KDFX RADAR ALSO INDICATES SOUTHERLY FLOW INTACT ALONG THE RIO GRANDE AND WE/LL ALSO MENTION TEMPO MVFR CONDITIONS AT KDRT. CLOUDS WILL LIFT/SCATTER WITH DAYTIME HEATING AND VFR CONDITIONS WILL RETURN THIS AFTERNOON. TOWARD THE END OF THE 30 HOUR TAFS... MVFR CIGS ARE LIKELY TO RETURN AFTER 16/04Z. && .PREV DISCUSSION... /ISSUED 947 PM CDT TUE APR 14 2015/ UPDATE... ONLY MINOR EDITS TO THE FORECAST PACKAGE. TRENDED THE HOURLY GRIDS TO REFLECT CURRENT OBSERVATIONS. POPS WERE TRIMMED BACK SLIGHTLY FOR THE OVERNIGHT PERIOD. THE HRRR DOES STILL SHOW SOME SHOWERS DEVELOPING OVERNIGHT ACROSS ATASCOSA...KARNES...AND DEWITT COUNTIES SO LEFT SLIGHT CHANCE POPS IN ACROSS THE COASTAL PLAINS. MORE SIGNIFICANT EDITS WERE MADE TO THE SKY GRIDS BASED ON CURRENT IR SATELLITE IMAGES AND MODEL FORECASTS OVERNIGHT. EXPECT A PARTLY TO MOSTLY CLOUDY NIGHT ACROSS SOUTH CENTRAL TEXAS. TREADWAY && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 82 64 80 65 80 / 10 10 60 60 50 AUSTIN BERGSTROM INTL AIRPORT 82 63 79 64 78 / 10 20 60 60 50 NEW BRAUNFELS MUNI AIRPORT 82 64 80 65 79 / 20 20 60 50 60 BURNET MUNI AIRPORT 81 63 78 63 77 / 10 20 60 60 50 DEL RIO INTL AIRPORT 85 65 83 65 81 / 20 40 40 50 50 GEORGETOWN MUNI AIRPORT 81 63 79 64 79 / 10 10 60 60 50 HONDO MUNI AIRPORT 83 65 81 65 78 / 20 20 50 50 60 SAN MARCOS MUNI AIRPORT 81 64 79 65 78 / 10 20 60 50 60 LA GRANGE - FAYETTE REGIONAL 81 65 80 67 80 / 20 20 60 50 70 SAN ANTONIO INTL AIRPORT 83 65 80 67 79 / 20 20 60 60 60 STINSON MUNI AIRPORT 84 66 80 67 78 / 20 20 50 50 60 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...24 SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1240 AM CDT WED APR 15 2015 .DISCUSSION...UPDATED FOR 06Z AVIATION. && .AVIATION...HAVE IMPROVED CIGS A BIT OVERNIGHT...SURFACE LAYER A BIT DRIER THAN RECENT TAF PERIODS AND SHOULD LIMIT LOW CLOUD DEVELOPMENT. COULD SEE SEE TEMPO PERIODS OF IFR CIGS FOR EASTERN SITES. PRECIP CHANCES CONTINUE TOMORROW...THOUGH ONLY 20-30 PERCENT. HAVE MAINLY VC GROUPS FOR SH AND TS. && .PREV DISCUSSION... /ISSUED 822 PM CDT TUE APR 14 2015/ DISCUSSION...CURRENTLY QUIET ACROSS THE CWA THIS EVENING. WATER VAPOR SATELLITE SHOWS DRIER MID/UPPER LEVELS ACROSS S TX, WHICH IS ALSO EVIDENT ON THE 00Z CRP SOUNDING, AND A SHORT WAVE ACROSS FAR W TX. THE SOUNDING ALSO SHOWED A MORE STABLE ENVIRONMENT THAN THE PAST FEW NIGHTS. AM NOT EXPECTING ANY ORGANIZED SVR WX TONIGHT, HOWEVER, A WEAK BDRY IS PROGD TO MEANDER ACROSS THE COASTAL BEND AND MOISTURE IS PROGD TO INCREASE OVERNIGHT. THE GFS/HRRR/RAP/ SHOW WEAK ECHOES/LIGHT PRECIP DVLPG ACROSS MAINLY THE E CWA OVERNIGHT. THEREFORE, WILL KEEP THE 20-30 POPS IN PLACE FOR TONIGHT. NO MAJOR CHANGES AT THIS TIME. PREV DISCUSSION... /ISSUED 725 PM CDT TUE APR 14 2015/ DISCUSSION...SEE AVIATION BELOW FOR 00Z TAF UPDATE. AVIATION....AVIATION...VFR CIGS ACROSS LRD/ALI/CRP...WITH HIGH END MVFR CIGS OVER VCT. CIGS LOWER ACROSS SOUTH TEXAS LATE TONIGHT/EARLY WEDNESDAY MORNING. PATCHY FOG IS A CONCERN AS WELL...WITH VSBYS ANTICIPATED TO BE REDUCED TO MVFR/IFR LVLS DURING THE EARLY MORNING WEDNESDAY AT ALI/CRP/VCT. THERE IS STILL A CHANCE FOR SHOWERS AND THUNDERSTORMS TO IMPACT SOUTH TEXAS TOMORROW...THOUGH COVERAGE WILL NOT BE AS HIGH THROUGH THE PERIOD. ANTICIPATE CIGS WILL RISE AND IMPROVE TO VFR CONDITIONS BY WEDNESDAY AFTERNOON. WINDS WILL GENERALLY REMAIN LIGHT THROUGH THE PERIOD...BECOMING VARIABLE OVERNIGHT...THEN E TO SE THROUGHOUT THE DAY. PREV DISCUSSION... /ISSUED 344 PM CDT TUE APR 14 2015/ SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...THE UPPER LOW HAS LIFTED NEWD OVER THE SRN PLAINS (WATER VAPOR IMAGERY/STREAMLINE DATA) LATE THIS AFTN...DECREASING SYNOPTIC SCALE LIFT OVER THE CWA/MSA. LATEST MSAS SUGGEST A WEAK BOUNDARY SW-NE ACRS THE CWA. LATEST LAPS ANALYSIS DEPICTS MAX CAPE VALUES NEAR 1000 J/KG OVER PORTIONS OF THE ERN CWA. EARLIER RAP OUTPUT SUGGESTED MAX CAPE VALUES AROUND 1500 J/KG THIS EVENING. ANTICIPATE AT LEAST ISOLD CONVECTION THIS EVENING/EARLY TNGT OVER THE CWA OWING TO LIMITED INSTABILITY/SFC FORCING. SREF PROBABILITIES SUGGEST AT LEAST PATCHY FOG OVER PORTIONS OF THE CWA DRG THE 09-14Z WEDNESDAY PERIOD. WEDNESDAY...THE GFS PROG THE LFQ OF AN UPPER JET STREAK ENTERING THE CWA BY THE AFTN. EARLIER NAM DETERMINISTIC OUTPUT DEPICTED 2000-3500 J/KG CAPE VALUES OVER THE CWA FOR THE AFTN HOURS. ANTICIPATE ISOD/SCT CONVECTION OVER THE CWA/MSA OWING TO INSTABILITY/WEAKENING SFC BOUNDARY/UPPER FORCING (HOWEVER MSTR MAY BECOME A LIMITING FACTOR OVR THE NERN CWA AS PWAT VALUES MAY FALL TO NEAR NORMAL DRG THE AFTN.) SOME STORMS MAY BECOME STG DRG THE AFTN/EARLY EVENING. WEDNESDAY NIGHT...THE GFS DETERMINISTIC MAINTAIN JET DYNAMICS OVER THE CWA WHICH MAY CONTRIBUTE TO ADDITIONAL AT LEAST ISOLD CONVECTION. LONG TERM (THURSDAY THROUGH TUESDAY)...ACTIVE WEATHER IS EXPECTED EARLY IN THE PERIOD AS A VERY STRONG SUBTROPICAL JET REMAINS FOCUSED ACRS THE AREA AND MSTR/INSTABILITY RETURN. BOTH THE GFS/EURO DEPICT 50+ MID LVL SPEED MAX IMPINGING ON THE AREA THU AFTN WITH STRONG UPPER SUPPORT IN THE FRONT LEFT QUAD OF THE UPPER JET. MSTR RETURN LOOKS ROBUST WITH 70+ DEWPOINTS SPREADING BACK OVER THE REGION. SO THE SVR POTNL WILL HINGE ON TOUGH TO PREDICT MESOSCALE DETAILS CONCERNING DEGREE OF INSOLATION AND ANY LINGERING BOUNDARIES ACRS THE RGN. AT A MINIMUM THE SYNOPTIC SETUP IS SUPPORTIVE OF SEVERE POTENTIAL AND CONDITIONALLY COULD SUPPORT A HIGHER END EVENT. ENOUGH SHEAR LOOKS TO BE IN PLACE SO THAT ALL MODES OF SVR WX ARE PSBL HWVR DAMAGING WINDS/HAIL FROM MULTICELL CLUSTERS/BOWS LOOKS MOST LIKELY. FRIDAY LOOKS POTENTIALLY ACTIVE AS WELL BUT AGAIN THE EVOLUTION OF EARLIER CONVECTION WILL HAVE A HUGE IMPACT ON HOW THINGS UNFOLD. AS FAR AS EXCESSIVE RAINS GO...VERY HEAVY PCPN OVERNIGHT...4-6 INCHES IN SPOTS...HAS INCREASED OUR FLOOD THREAT QUITE A BIT. DEEP CONVECTION COULD QUICKLY LEAD TO ADDITIONAL FLOODING THU AND ESPLY FRI WHEN PWATS APPRCH 2 INCHES ON THE LATEST MODELS. WILL ISSUE SPS TO ADDRESS SVR/+RA THREATS DURING THE LATE WEEK PERIOD. WILL LEAN TWRD SLOWER FROPA DEPICTED BY THE EURO AND KEEP POPS GOING THRU MOST OF THE WEEKEND. AGAIN SOME POTENTIAL REMAINS FOR STRONG STORMS AND HEAVY RAINS ON SAT. DRIER AIR SHOULD WIN OUT BY SUNDAY AS UPPER LOW FINALLY PULLS EAST. NO MAJOR CHANGES TO PREV TEMP FCSTS WERE MADE - GENERALLY LEANED TWRD THE COOLER HPC NUMBERS VS THE WARMER MEX WITH THE CLOUD/PCPN. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 81 70 80 71 81 / 30 20 50 40 60 VICTORIA 81 67 78 68 79 / 30 20 60 40 60 LAREDO 85 69 86 70 85 / 20 20 40 30 40 ALICE 84 68 83 70 83 / 30 20 50 40 60 ROCKPORT 78 70 76 71 76 / 30 20 60 40 60 COTULLA 84 67 82 68 83 / 20 20 40 30 40 KINGSVILLE 84 69 82 71 83 / 30 20 40 30 60 NAVY CORPUS 78 70 77 71 78 / 30 20 50 40 60 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ PZ/83...AVIATION
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
133 PM EDT WED APR 15 2015 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS THE CAROLINAS TODAY INTO AT LEAST THURSDAY. WEAK WAVES OF LOW PRESSURE RIDING NORTHEAST ALONG THE FRONT WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE TO KEEP COOL AND DAMP CONDITIONS IN PLACE OVER THE NEXT COUPLE OF DAYS. SLIGHTLY WARMER AIR RETURNS BY WEEKS END AHEAD OF ANOTHER COLD FRONT THAT WILL CROSS THE AREA OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1130 AM EDT WEDNESDAY... SENDING AN UPDATE TO RAISE POPS TO MORE WIDESPREAD LIKELY TO CATEGORICAL COVERAGE ESPCLY IN THE WEST GIVEN CURRENT EXPANSE OF RAIN SEEN TO THE SW WITH THE NEXT WAVE. APPEARS LATEST HRRR NOW BEST IN SLIDING MUCH OF THIS ACROSS THE WESTERN HALF THIS MORNING BEFORE COVERAGE WEAKENS AND SHIFTS SE AS THE WEDGE DEEPENS FROM THE NE. ALSO BUMPED UP POPS JUST EAST OF THE BLUE RIDGE WHERE A PERIOD OF RAIN ALSO LIKELY INTO THIS AFTERNOON BEFORE SOME DRYING OCCURS FROM THE NE LATER ON. ALSO LOWERED TEMPS A LITTLE MORE BASED ON CURRENT VALUES AND LIKELY LIMITED RISES UNDER THE CLOUDS/RAIN INTO MUCH OF THE AFTERNOON. EXPECT SOME SPOTS WILL ONLY RISE A FEW DEGREES AT BEST WITH HIGHS MOSTLY 50S. PREVIOUS DISCUSSION AS OF 252 AM EDT WEDNESDAY... FRONT NOW WELL TO THE SOUTH REMAINS THE FOCUS FOR ADDED PRECIP CHANCES OVER THE NEXT 24 HOURS AS PIECES OF ENERGY EJECT EAST FROM THE RESIDUAL 5H LOW OVER THE PLAINS AND CAUSE WEAK SURFACE WAVES ALONG THE BOUNDARY. THIS WHILE LOW LEVEL WEDGING ENHANCES ALONG/EAST OF THE MOUNTAINS AS HIGH PRESSURE BUILDS TO THE NORTH AND EVENTUALLY DOWN THE MID ATLANTIC COAST LATER TONIGHT. SQUEEZE PLAY IN BETWEEN THE TWO TO MAKE FOR ADDED PERIODS OF RAIN ESPCLY SOUTHERN HALF TODAY AND ACROSS THE SOUTH AND WEST OVERNIGHT. HOWEVER JUST HOW FAR NORTH SIGNIFICANT RAIN MAKES IT TODAY STILL TRICKY GIVEN DIFFERING MODEL SOLUTIONS ON TIMING OF THE DEVELOPING WEDGE FROM THE NE AND STRENGTH OF OVERRUNNING/DIFFLUENCE ALOFT PER JET AXIS OVERTOP THE CAD THROUGH THE AFTERNOON. LATEST HRRR QUITE WET ACROSS THE REGION BUT APPEARS RATHER FAST AND PERHAPS OVERDONE SIMILAR TO THE NAM...WHILE THE GFS/EC AND HIRES GUIDANCE BRING DEEP MOISTURE INTO THE SOUTH/SW THIS MORNING BEFORE SHUNTING MORE TO THE SE LATER IN THE DAY. SINCE APPEARS OFF THE LATEST OBS/MSAS THAT THE WEDGE IS MAKING SOME INROADS FROM THE NORTH WILL FOLLOW CLOSER TO THE LATEST SREF COMPROMISE AND RAISE POPS TO LIKELY SOUTHERN TIER AND HIGHER CHANCES WEST WITH ONLY LOW TO SLIGHT POPS FAR NE TODAY. DOESN`T APPEAR RAINFALL RATES OR FORECAST QPF WILL BE HIGH ENOUGH TO CAUSE THE NEED FOR ANY FLOOD WATCHES AT THIS TIME OVER THE SW GIVEN LESS UPSLOPE BUT ANOTHER GOOD HALF TO AN INCH POSSIBLE NW NC MOUNTAINS. LEFT TEMPS QUITE COOL GIVEN THE WEDGE UNDER LOW CLOUDS/RAIN WITH HIGHS ONLY RISING A BIT INTO THE 50S...TO PERHAPS AROUND 60 IN SPOTS OVER THE FAR WEST...AND NE WHERE SOME BREAKS IN THE LOW DECK COULD OCCUR AT TIMES. UPPER SUPPORT ELONGATES OUT OVERNIGHT AS THE REGION REMAINS STUCK BETWEEN HIGH PRESSURE NOSING IN FROM THE NE AND RESIDUAL LOW PRESSURE BACK ALONG THE MISSISSIPPI RIVER. THIS SHOULD ALLOW THE FLOW TO BECOME MORE OF A SE UPSLOPE COMPONENT OVER THE SW AS ANOTHER WAVE OF LIFT PUSHES EAST TOWARD THE MOUNTAINS FROM SHORTWAVE ENERGY PASSING WELL TO THE NW. SOME SOLUTIONS ESPCLY THE NAM/EC BASICALLY CONNECT THE AXIS OF DEEPER MOISTURE/LIFT FROM TODAY OVER THE SE TO THE NEXT IMPULSE HEADING IN FROM THE WEST. THIS WOULD KEEP RAIN GOING FROM SE WEST VA ACROSS EXTREME SW VA INTO NW NC FOR MUCH OF THE NIGHT WHILE HAVING THINGS DRY OUT TO SOME DEGREE OVER THE NE. AGAIN THINK THIS IS OVERDONE BUT EXPECT MORE RAIN TO ARRIVE WEST LATE SO UPPED POPS TO HIGHER CHANCE WESTERN HALF...AND KEPT LIKELY/CHANCE GOING SW OVERNIGHT FOR BETTER SE FLOW. LOWS MOSTLY ON THE COOL SIDE WITH 40S MOST SPOTS UNDER THE CAD BY MORNING. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 400 AM EDT WEDNESDAY... UNSETTLED WEATHER WILL CONTINUE INTO THE WEEKEND. A 1033 MB HIGH PRESSURE WILL WEDGE DOWN THE EAST COAST THURSDAY AND WEAKEN AS IT SLIDE EAST THURSDAY NIGHT INTO FRIDAY. MODELS ARE STILL DISPLAYING A SURFACE REFLECTIONS OFF THE SOUTHEAST COAST...WHICH INTENSIFIES INTO A SURFACE LOW AND LIFTS NORTHWARD INTO FRIDAY. THE PRESSURE GRADIENT BETWEEN THE HIGH PRESSURE TO THE NORTH AND LOW PRESSURE TO SOUTH WILL BRING A STRONG FETCH OF ATLANTIC MOISTURE TOWARDS THE SOUTH-CENTRAL APPALACHIANS. MAINTAIN HIGHEST POPS ALONG THE BLUE RIDGE THURSDAY. UNDER PLENTY OF CLOUDS...LEANED TOWARDS THE COOLER MOS FOR HIGH TEMPERATURES THURSDAY WITH READINGS FROM THE UPPER 40S IN THE MOUNTAINS TO THE UPPER 50S IN THE PIEDMONT. FOR THURSDAY NIGHT...LEANED POPS TOWARDS THE NAM WITH HIGHER POPS ALONG THE BLUE RIDGE...THEN TAPERING OFF BY 12Z FRIDAY. LOW TEMPERATURES THURSDAY NIGHT WILL RANGE FROM THE LOWER 40S IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT. ON FRIDAY...THE COASTAL LOW LIFTS NORTH INTO THE ATLANTIC OCEAN...WHILE A WHILE WEAK HIGH PRESSURE DRIFTS OVER THE REGION. A SHORTWAVE WILL ROTATE EAST AROUND THE UPPER TROUGH FRIDAY INTO FRIDAY NIGHT. A WEAK COLD FRONT/SURFACE TROUGH MOVES INTO THE AREA FRIDAY AFTERNOON AND WASHES OUT. HIGH TEMPERATURES ON FRIDAY WILL BE WARMER THAN THURSDAY WITH VALUES VARYING FROM THE UPPER 50S IN THE MOUNTAINS TO LOWER 70S IN THE PIEDMONT. WITH DRIER AIR MOVING IN ALOFT CUT BACK POPS FOR FRIDAY NIGHT TO SLIGHT CHANCE. LOW TEMPERATURES FRIDAY NIGHT WILL DROP INTO THE UPPER 40S IN THE WEST TO THE LOWER TO MID 50S IN THE EAST. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 245 PM EDT TUESDAY... A COLD FRONT IS EXPECTED TO STALL ACROSS THE OHIO VALLEY ON SATURDAY WITH A POSSIBLE CLOSED LOW HOVERING OVER THE OZARKS. THERE WILL REMAIN A GOOD FLOW OF MOISTURE INTO THE REGION FROM THE GULF THROUGH THE WEEKEND TO KEEP HIGH CHANCE POPS. THE MAIN QUESTION REGARDING RAIN IS TIMING. HIGH PRESSURE DRIFTS OVER THE REGION EARLY NEXT WEEK TO BRING AN END TO THE RAIN. WITH MORE CLOUDS AND RAIN IN THE FORECAST...TEMPERATURES WILL BE COOL BUT NOT TO FAR REMOVED FROM NORMAL. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 130 AM EDT WEDNESDAY... THE FORECAST AREA WILL BE IN BETWEEN SHORT WAVES THROUGH EARLY AFTERNOON...ALLOWING CEILINGS AND VISIBILITIES TO LIFT TO VFR INTO THIS EVENING. WARM MOIST AIR WILL CONTINUE TO OVERRUN DRY COOL AIR WORKING SOUTH ACROSS THE FOOTHILLS AND PIEDMONT OVERNIGHT. WITH LOSE OF HEATING AND CONTINUED EASTERLY FLOW...EXPECTING CLOUDS TO LOWER TO MVFR CONDITIONS WITH SPOTTY LIGHT RAIN/DRIZZLE THROUGH MOST OF THE NIGHT. CONDITIONS WILL IMPROVE TO VFR LATE THURSDAY MORNING. EXTENDED AVIATION... ON FRIDAY...LOW LEVEL FLOW TURNS TO THE SOUTHWEST IN ADVANCE OF A COLD FRONT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE IN THE AFTERNOON...ESPECIALLY ONCE THE WEDGE BREAKS. ON SATURDAY THE FRONT COMES THROUGH SHOWERS AND THUNDERSTORMS. EXPECTING OCCASIONAL PERIODS OF MVFR CONDITIONS UNTIL THE FRONT PASSES. SUNDAY A DRIER AIR MASS WILL PUSH INTO THE REGION ALONG WITH HIGH PRESSURE BEHIND THE FRONT. THIS IS A SLOWER TIMING THAN THE PAST FEW RUNS OF THE MODELS. ONCE THIS DRIER AIR ARRIVES...CONDITIONS SHOULD IMPROVE BACK TO VFR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH/WP NEAR TERM...JH/RCS SHORT TERM...KK LONG TERM...RCS AVIATION...AMS/JH/MBS HYDROLOGY...JH/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
651 AM EDT WED APR 15 2015 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS THE CAROLINAS TODAY INTO AT LEAST THURSDAY. WEAK WAVES OF LOW PRESSURE RIDING NORTHEAST ALONG THE FRONT WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE TO KEEP COOL AND DAMP CONDITIONS IN PLACE OVER THE NEXT COUPLE OF DAYS. SLIGHTLY WARMER AIR RETURNS BY WEEKS END AHEAD OF ANOTHER COLD FRONT THAT WILL CROSS THE AREA OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 550 AM EDT WEDNESDAY... SENDING AN UPDATE TO RAISE POPS TO MORE WIDESPREAD LIKELY TO CATEGORICAL COVERAGE ESPCLY IN THE WEST GIVEN CURRENT EXPANSE OF RAIN SEEN TO THE SW WITH THE NEXT WAVE. APPEARS LATEST HRRR NOW BEST IN SLIDING MUCH OF THIS ACROSS THE WESTERN HALF THIS MORNING BEFORE COVERAGE WEAKENS AND SHIFTS SE AS THE WEDGE DEEPENS FROM THE NE. ALSO BUMPED UP POPS JUST EAST OF THE BLUE RIDGE WHERE A PERIOD OF RAIN ALSO LIKELY INTO THIS AFTERNOON BEFORE SOME DRYING OCCURS FROM THE NE LATER ON. ALSO LOWERED TEMPS A LITTLE MORE BASED ON CURRENT VALUES AND LIKELY LIMITED RISES UNDER THE CLOUDS/RAIN INTO MUCH OF THE AFTERNOON. EXPECT SOME SPOTS WILL ONLY RISE A FEW DEGREES AT BEST WITH HIGHS MOSTLY 50S. PREVIOUS DISCUSSION AS OF 252 AM EDT WEDNESDAY... FRONT NOW WELL TO THE SOUTH REMAINS THE FOCUS FOR ADDED PRECIP CHANCES OVER THE NEXT 24 HOURS AS PIECES OF ENERGY EJECT EAST FROM THE RESIDUAL 5H LOW OVER THE PLAINS AND CAUSE WEAK SURFACE WAVES ALONG THE BOUNDARY. THIS WHILE LOW LEVEL WEDGING ENHANCES ALONG/EAST OF THE MOUNTAINS AS HIGH PRESSURE BUILDS TO THE NORTH AND EVENTUALLY DOWN THE MID ATLANTIC COAST LATER TONIGHT. SQUEEZE PLAY IN BETWEEN THE TWO TO MAKE FOR ADDED PERIODS OF RAIN ESPCLY SOUTHERN HALF TODAY AND ACROSS THE SOUTH AND WEST OVERNIGHT. HOWEVER JUST HOW FAR NORTH SIGNIFICANT RAIN MAKES IT TODAY STILL TRICKY GIVEN DIFFERING MODEL SOLUTIONS ON TIMING OF THE DEVELOPING WEDGE FROM THE NE AND STRENGTH OF OVERRUNNING/DIFFLUENCE ALOFT PER JET AXIS OVERTOP THE CAD THROUGH THE AFTERNOON. LATEST HRRR QUITE WET ACROSS THE REGION BUT APPEARS RATHER FAST AND PERHAPS OVERDONE SIMILAR TO THE NAM...WHILE THE GFS/EC AND HIRES GUIDANCE BRING DEEP MOISTURE INTO THE SOUTH/SW THIS MORNING BEFORE SHUNTING MORE TO THE SE LATER IN THE DAY. SINCE APPEARS OFF THE LATEST OBS/MSAS THAT THE WEDGE IS MAKING SOME INROADS FROM THE NORTH WILL FOLLOW CLOSER TO THE LATEST SREF COMPROMISE AND RAISE POPS TO LIKELY SOUTHERN TIER AND HIGHER CHANCES WEST WITH ONLY LOW TO SLIGHT POPS FAR NE TODAY. DOESN`T APPEAR RAINFALL RATES OR FORECAST QPF WILL BE HIGH ENOUGH TO CAUSE THE NEED FOR ANY FLOOD WATCHES AT THIS TIME OVER THE SW GIVEN LESS UPSLOPE BUT ANOTHER GOOD HALF TO AN INCH POSSIBLE NW NC MOUNTAINS. LEFT TEMPS QUITE COOL GIVEN THE WEDGE UNDER LOW CLOUDS/RAIN WITH HIGHS ONLY RISING A BIT INTO THE 50S...TO PERHAPS AROUND 60 IN SPOTS OVER THE FAR WEST...AND NE WHERE SOME BREAKS IN THE LOW DECK COULD OCCUR AT TIMES. UPPER SUPPORT ELONGATES OUT OVERNIGHT AS THE REGION REMAINS STUCK BETWEEN HIGH PRESSURE NOSING IN FROM THE NE AND RESIDUAL LOW PRESSURE BACK ALONG THE MISSISSIPPI RIVER. THIS SHOULD ALLOW THE FLOW TO BECOME MORE OF A SE UPSLOPE COMPONENT OVER THE SW AS ANOTHER WAVE OF LIFT PUSHES EAST TOWARD THE MOUNTAINS FROM SHORTWAVE ENERGY PASSING WELL TO THE NW. SOME SOLUTIONS ESPCLY THE NAM/EC BASICALLY CONNECT THE AXIS OF DEEPER MOISTURE/LIFT FROM TODAY OVER THE SE TO THE NEXT IMPULSE HEADING IN FROM THE WEST. THIS WOULD KEEP RAIN GOING FROM SE WEST VA ACROSS EXTREME SW VA INTO NW NC FOR MUCH OF THE NIGHT WHILE HAVING THINGS DRY OUT TO SOME DEGREE OVER THE NE. AGAIN THINK THIS IS OVERDONE BUT EXPECT MORE RAIN TO ARRIVE WEST LATE SO UPPED POPS TO HIGHER CHANCE WESTERN HALF...AND KEPT LIKELY/CHANCE GOING SW OVERNIGHT FOR BETTER SE FLOW. LOWS MOSTLY ON THE COOL SIDE WITH 40S MOST SPOTS UNDER THE CAD BY MORNING. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 400 AM EDT WEDNESDAY... UNSETTLED WEATHER WILL CONTINUE INTO THE WEEKEND. A 1033 MB HIGH PRESSURE WILL WEDGE DOWN THE EAST COAST THURSDAY AND WEAKEN AS IT SLIDE EAST THURSDAY NIGHT INTO FRIDAY. MODELS ARE STILL DISPLAYING A SURFACE REFLECTIONS OFF THE SOUTHEAST COAST...WHICH INTENSIFIES INTO A SURFACE LOW AND LIFTS NORTHWARD INTO FRIDAY. THE PRESSURE GRADIENT BETWEEN THE HIGH PRESSURE TO THE NORTH AND LOW PRESSURE TO SOUTH WILL BRING A STRONG FETCH OF ATLANTIC MOISTURE TOWARDS THE SOUTH-CENTRAL APPALACHIANS. MAINTAIN HIGHEST POPS ALONG THE BLUE RIDGE THURSDAY. UNDER PLENTY OF CLOUDS...LEANED TOWARDS THE COOLER MOS FOR HIGH TEMPERATURES THURSDAY WITH READINGS FROM THE UPPER 40S IN THE MOUNTAINS TO THE UPPER 50S IN THE PIEDMONT. FOR THURSDAY NIGHT...LEANED POPS TOWARDS THE NAM WITH HIGHER POPS ALONG THE BLUE RIDGE...THEN TAPERING OFF BY 12Z FRIDAY. LOW TEMPERATURES THURSDAY NIGHT WILL RANGE FROM THE LOWER 40S IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT. ON FRIDAY...THE COASTAL LOW LIFTS NORTH INTO THE ATLANTIC OCEAN...WHILE A WHILE WEAK HIGH PRESSURE DRIFTS OVER THE REGION. A SHORTWAVE WILL ROTATE EAST AROUND THE UPPER TROUGH FRIDAY INTO FRIDAY NIGHT. A WEAK COLD FRONT/SURFACE TROUGH MOVES INTO THE AREA FRIDAY AFTERNOON AND WASHES OUT. HIGH TEMPERATURES ON FRIDAY WILL BE WARMER THAN THURSDAY WITH VALUES VARYING FROM THE UPPER 50S IN THE MOUNTAINS TO LOWER 70S IN THE PIEDMONT. WITH DRIER AIR MOVING IN ALOFT CUT BACK POPS FOR FRIDAY NIGHT TO SLIGHT CHANCE. LOW TEMPERATURES FRIDAY NIGHT WILL DROP INTO THE UPPER 40S IN THE WEST TO THE LOWER TO MID 50S IN THE EAST. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 245 PM EDT TUESDAY... A COLD FRONT IS EXPECTED TO STALL ACROSS THE OHIO VALLEY ON SATURDAY WITH A POSSIBLE CLOSED LOW HOVERING OVER THE OZARKS. THERE WILL REMAIN A GOOD FLOW OF MOISTURE INTO THE REGION FROM THE GULF THROUGH THE WEEKEND TO KEEP HIGH CHANCE POPS. THE MAIN QUESTION REGARDING RAIN IS TIMING. HIGH PRESSURE DRIFTS OVER THE REGION EARLY NEXT WEEK TO BRING AN END TO THE RAIN. WITH MORE CLOUDS AND RAIN IN THE FORECAST...TEMPERATURES WILL BE COOL BUT NOT TO FAR REMOVED FROM NORMAL. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 633 AM EDT WEDNESDAY... FLYING CONDITIONS WILL CONTINUE TO QUICKLY DETERIORATE THIS MORNING AS THE NEXT WAVE OF LOW PRESSURE SWINGS ANOTHER SWATH OF LIGHT TO MODERATE RAIN IN FROM THE SW. THIS SHOULD HELP PUSH CIGS BACK DOWN THROUGH MVFR TO IFR IN MANY LOCATIONS BY MID/LATE MORNING...WITH MVFR VSBYS OR WORSE INCLUDING MOUNTAIN OBSCURATIONS INTO AT LEAST EARLY THIS AFTERNOON. SQUEEZE PLAY CONTINUES THIS AFTERNOON WITH HIGH PRESSURE STRENGTHENING EAST OF THE BLUE RIDGE AND MOISTURE SLOWLY DIMINISHING AND SHUNTING TO THE SOUTH BY LATER IN THE AFTERNOON. HOWEVER HOW FAST CIGS IMPROVE A BIT IFFY GIVEN SLOWER EXODUS OF MOISTURE OFF LATEST MODELS AND EASTERLY FLOW. FOR NOW WILL HOLD ALL LOCATIONS EXCLUDING KLYH SUB-VFR UNTIL 00Z/8PM WHEN EXPECTING BETTER DRYING TO TAKE SHAPE BEHIND THE CURRENT WAVE. MODELS DISAGREE ON HOW FAST THE PRECIP WEDNESDAY EVENING GETS SHUNTED TO THE SOUTH WITH THE NAM QUITE WET INTO THURSDAY WITH OTHERS SHOWING A BREAK WED NIGHT AND THEN MORE -RA WITH ANOTHER FEATURE ON THURSDAY. EITHER WAY APPEARS OVERALL SUB-VFR WILL BE THE RULE WITH ONLY PERIODIC IMPROVEMENT POSSIBLY OCCURRING ACROSS NORTHERN SECTIONS...AFFECTING THE KLWB-KLYH ROUTE. EXTENDED AVIATION... THE WEDGE REMAINS IN PLACE INTO FRIDAY MORNING WITH CONTINUED IFR TO MVFR CEILINGS AND OCNL MVFR VSBYS IN -RA/DZ/FOG. ON FRIDAY...LOW LEVEL FLOW TURNS TO THE SOUTHWEST IN ADVANCE OF A COLD FRONT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE IN THE AFTERNOON...ESPECIALLY ONCE THE WEDGE BREAKS. ON SATURDAY THE FRONT COMES THROUGH SHOWERS AND THUNDERSTORMS. EXPECTING OCCASIONAL PERIODS OF MVFR CONDITIONS UNTIL THE FRONT PASSES. SUNDAY A DRIER AIR MASS WILL PUSH INTO THE REGION ALONG WITH HIGH PRESSURE BEHIND THE FRONT. THIS IS A SLOWER TIMING THAN THE PAST FEW RUNS OF THE MODELS. ONCE THIS DRIER AIR ARRIVES...CONDITIONS SHOULD IMPROVE BACK TO VFR. && .HYDROLOGY... AS OF 400 AM EDT WEDNESDAY... RUNOFF FROM EARLIER HEAVY RAINFALL OF AROUND 2 INCHES IN SPOTS ACROSS THE GREENBRIER VALLEY AND VIRGINIA HIGHLANDS WILL CONTINUE TO FILTER INTO MAINSTEM WATERWAYS AND RESULT IN NEAR BANKFULL CONDITIONS FOR MANY STREAMS AND CREEKS TODAY. HOWEVER LATEST FORECASTS SUGGEST THAT MOST RIVERS INCLUDING THE GREENBRIER AT ALDERSON AND THE JAMES DOWNSTREAM FROM LICK RUN WILL REMAIN BELOW FLOOD STAGE BASED ON THIS EARLIER RAINFALL. ADDITIONAL RAIN WILL SPREAD BACK ACROSS THE REGION TODAY RESULTING IN ANOTHER HALF TO ONE INCH OR MORE ACROSS THE MOUNTAINS OF NORTHWEST NORTH CAROLINA AS WELL AS PORTIONS OF SOUTHWEST VIRGINIA. HOWEVER RAINFALL RATES AND FORECASTED QPF SHOULD NOT BE ENOUGH TO CAUSE FLOOD PROBLEMS BUT WILL NEED TO BE WATCHED GIVEN DIFFERING FLASH FLOOD GUIDANCE ACROSS THE REGION. ELSEWHERE TOTALS ARE EXPECTED TO REMAIN LIGHTER WITH TOTALS RANGING FROM A QUARTER/HALF INCH OVER THE SW TO A TENTH TO ONE QUARTER OF AN INCH ALONG THE INTERSTATE 64 CORRIDOR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH/WP NEAR TERM...JH SHORT TERM...KK LONG TERM...RCS AVIATION...AMS/JH/MBS HYDROLOGY...JH/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
558 AM EDT WED APR 15 2015 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS THE CAROLINAS TODAY INTO AT LEAST THURSDAY. WEAK WAVES OF LOW PRESSURE RIDING NORTHEAST ALONG THE FRONT WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE TO KEEP COOL AND DAMP CONDITIONS IN PLACE OVER THE NEXT COUPLE OF DAYS. SLIGHTLY WARMER AIR RETURNS BY WEEKS END AHEAD OF ANOTHER COLD FRONT THAT WILL CROSS THE AREA OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 550 AM EDT WEDNESDAY... SENDING AN UPDATE TO RAISE POPS TO MORE WIDESPREAD LIKELY TO CATEGORICAL COVERAGE ESPCLY IN THE WEST GIVEN CURRENT EXPANSE OF RAIN SEEN TO THE SW WITH THE NEXT WAVE. APPEARS LATEST HRRR NOW BEST IN SLIDING MUCH OF THIS ACROSS THE WESTERN HALF THIS MORNING BEFORE COVERAGE WEAKENS AND SHIFTS SE AS THE WEDGE DEEPENS FROM THE NE. ALSO BUMPED UP POPS JUST EAST OF THE BLUE RIDGE WHERE A PERIOD OF RAIN ALSO LIKELY INTO THIS AFTERNOON BEFORE SOME DRYING OCCURS FROM THE NE LATER ON. ALSO LOWERED TEMPS A LITTLE MORE BASED ON CURRENT VALUES AND LIKELY LIMITED RISES UNDER THE CLOUDS/RAIN INTO MUCH OF THE AFTERNOON. EXPECT SOME SPOTS WILL ONLY RISE A FEW DEGREES AT BEST WITH HIGHS MOSTLY 50S. PREVIOUS DISCUSSION AS OF 252 AM EDT WEDNESDAY... FRONT NOW WELL TO THE SOUTH REMAINS THE FOCUS FOR ADDED PRECIP CHANCES OVER THE NEXT 24 HOURS AS PIECES OF ENERGY EJECT EAST FROM THE RESIDUAL 5H LOW OVER THE PLAINS AND CAUSE WEAK SURFACE WAVES ALONG THE BOUNDARY. THIS WHILE LOW LEVEL WEDGING ENHANCES ALONG/EAST OF THE MOUNTAINS AS HIGH PRESSURE BUILDS TO THE NORTH AND EVENTUALLY DOWN THE MID ATLANTIC COAST LATER TONIGHT. SQUEEZE PLAY IN BETWEEN THE TWO TO MAKE FOR ADDED PERIODS OF RAIN ESPCLY SOUTHERN HALF TODAY AND ACROSS THE SOUTH AND WEST OVERNIGHT. HOWEVER JUST HOW FAR NORTH SIGNIFICANT RAIN MAKES IT TODAY STILL TRICKY GIVEN DIFFERING MODEL SOLUTIONS ON TIMING OF THE DEVELOPING WEDGE FROM THE NE AND STRENGTH OF OVERRUNNING/DIFFLUENCE ALOFT PER JET AXIS OVERTOP THE CAD THROUGH THE AFTERNOON. LATEST HRRR QUITE WET ACROSS THE REGION BUT APPEARS RATHER FAST AND PERHAPS OVERDONE SIMILAR TO THE NAM...WHILE THE GFS/EC AND HIRES GUIDANCE BRING DEEP MOISTURE INTO THE SOUTH/SW THIS MORNING BEFORE SHUNTING MORE TO THE SE LATER IN THE DAY. SINCE APPEARS OFF THE LATEST OBS/MSAS THAT THE WEDGE IS MAKING SOME INROADS FROM THE NORTH WILL FOLLOW CLOSER TO THE LATEST SREF COMPROMISE AND RAISE POPS TO LIKELY SOUTHERN TIER AND HIGHER CHANCES WEST WITH ONLY LOW TO SLIGHT POPS FAR NE TODAY. DOESN`T APPEAR RAINFALL RATES OR FORECAST QPF WILL BE HIGH ENOUGH TO CAUSE THE NEED FOR ANY FLOOD WATCHES AT THIS TIME OVER THE SW GIVEN LESS UPSLOPE BUT ANOTHER GOOD HALF TO AN INCH POSSIBLE NW NC MOUNTAINS. LEFT TEMPS QUITE COOL GIVEN THE WEDGE UNDER LOW CLOUDS/RAIN WITH HIGHS ONLY RISING A BIT INTO THE 50S...TO PERHAPS AROUND 60 IN SPOTS OVER THE FAR WEST...AND NE WHERE SOME BREAKS IN THE LOW DECK COULD OCCUR AT TIMES. UPPER SUPPORT ELONGATES OUT OVERNIGHT AS THE REGION REMAINS STUCK BETWEEN HIGH PRESSURE NOSING IN FROM THE NE AND RESIDUAL LOW PRESSURE BACK ALONG THE MISSISSIPPI RIVER. THIS SHOULD ALLOW THE FLOW TO BECOME MORE OF A SE UPSLOPE COMPONENT OVER THE SW AS ANOTHER WAVE OF LIFT PUSHES EAST TOWARD THE MOUNTAINS FROM SHORTWAVE ENERGY PASSING WELL TO THE NW. SOME SOLUTIONS ESPCLY THE NAM/EC BASICALLY CONNECT THE AXIS OF DEEPER MOISTURE/LIFT FROM TODAY OVER THE SE TO THE NEXT IMPULSE HEADING IN FROM THE WEST. THIS WOULD KEEP RAIN GOING FROM SE WEST VA ACROSS EXTREME SW VA INTO NW NC FOR MUCH OF THE NIGHT WHILE HAVING THINGS DRY OUT TO SOME DEGREE OVER THE NE. AGAIN THINK THIS IS OVERDONE BUT EXPECT MORE RAIN TO ARRIVE WEST LATE SO UPPED POPS TO HIGHER CHANCE WESTERN HALF...AND KEPT LIKELY/CHANCE GOING SW OVERNIGHT FOR BETTER SE FLOW. LOWS MOSTLY ON THE COOL SIDE WITH 40S MOST SPOTS UNDER THE CAD BY MORNING. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 400 AM EDT WEDNESDAY... UNSETTLED WEATHER WILL CONTINUE INTO THE WEEKEND. A 1033 MB HIGH PRESSURE WILL WEDGE DOWN THE EAST COAST THURSDAY AND WEAKEN AS IT SLIDE EAST THURSDAY NIGHT INTO FRIDAY. MODELS ARE STILL DISPLAYING A SURFACE REFLECTIONS OFF THE SOUTHEAST COAST...WHICH INTENSIFIES INTO A SURFACE LOW AND LIFTS NORTHWARD INTO FRIDAY. THE PRESSURE GRADIENT BETWEEN THE HIGH PRESSURE TO THE NORTH AND LOW PRESSURE TO SOUTH WILL BRING A STRONG FETCH OF ATLANTIC MOISTURE TOWARDS THE SOUTH-CENTRAL APPALACHIANS. MAINTAIN HIGHEST POPS ALONG THE BLUE RIDGE THURSDAY. UNDER PLENTY OF CLOUDS...LEANED TOWARDS THE COOLER MOS FOR HIGH TEMPERATURES THURSDAY WITH READINGS FROM THE UPPER 40S IN THE MOUNTAINS TO THE UPPER 50S IN THE PIEDMONT. FOR THURSDAY NIGHT...LEANED POPS TOWARDS THE NAM WITH HIGHER POPS ALONG THE BLUE RIDGE...THEN TAPERING OFF BY 12Z FRIDAY. LOW TEMPERATURES THURSDAY NIGHT WILL RANGE FROM THE LOWER 40S IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT. ON FRIDAY...THE COASTAL LOW LIFTS NORTH INTO THE ATLANTIC OCEAN...WHILE A WHILE WEAK HIGH PRESSURE DRIFTS OVER THE REGION. A SHORTWAVE WILL ROTATE EAST AROUND THE UPPER TROUGH FRIDAY INTO FRIDAY NIGHT. A WEAK COLD FRONT/SURFACE TROUGH MOVES INTO THE AREA FRIDAY AFTERNOON AND WASHES OUT. HIGH TEMPERATURES ON FRIDAY WILL BE WARMER THAN THURSDAY WITH VALUES VARYING FROM THE UPPER 50S IN THE MOUNTAINS TO LOWER 70S IN THE PIEDMONT. WITH DRIER AIR MOVING IN ALOFT CUT BACK POPS FOR FRIDAY NIGHT TO SLIGHT CHANCE. LOW TEMPERATURES FRIDAY NIGHT WILL DROP INTO THE UPPER 40S IN THE WEST TO THE LOWER TO MID 50S IN THE EAST. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 245 PM EDT TUESDAY... A COLD FRONT IS EXPECTED TO STALL ACROSS THE OHIO VALLEY ON SATURDAY WITH A POSSIBLE CLOSED LOW HOVERING OVER THE OZARKS. THERE WILL REMAIN A GOOD FLOW OF MOISTURE INTO THE REGION FROM THE GULF THROUGH THE WEEKEND TO KEEP HIGH CHANCE POPS. THE MAIN QUESTION REGARDING RAIN IS TIMING. HIGH PRESSURE DRIFTS OVER THE REGION EARLY NEXT WEEK TO BRING AN END TO THE RAIN. WITH MORE CLOUDS AND RAIN IN THE FORECAST...TEMPERATURES WILL BE COOL BUT NOT TO FAR REMOVED FROM NORMAL. && .AVIATION /10Z WEDNESDAY THROUGH SUNDAY/... AS OF 100 AM EDT WEDNESDAY... CIGS HAVE SLOWLY IMPROVED TO AT LEAST MVFR IN MANY LOCATIONS OVERNIGHT WITH THE EXCEPTION OF SPOTS ALONG THE RIDGES WHERE IFR/LIFR IN STRATUS/FOG/DZ PERSISTS. HOWEVER EXPECT ANY BRIEF DRYING BEHIND THE INITIAL EXITING WAVE TO END TOWARD DAYBREAK AS ANOTHER IMPULSE PUSHES DEEPER MOISTURE INCLUDING -RA BACK NE INTO THE AREA. AHEAD OF THIS EXPECTING VARYING CONDITIONS FROM MORE MVFR/IFR IN LOW CLOUDS/FOG OVER THE MOUNTAINS TO PERHAPS MORE HIGH END MVFR FROM KROA AND POINTS EAST AS DRY AIR UNDER HIGH PRESSURE TO THE NORTH WEDGES IN. SQUEEZE PLAY CONTINUES ON WEDNESDAY WITH HIGH PRESSURE STRENGTHENING EAST OF THE BLUE RIDGE AND MOISTURE TRYING TO RIDE IN FROM THE SW WITH THE NEXT IMPULSE. HOW FAR NORTH/NE TO TAKE PRECIP REMAINS LOW CONFIDENCE BUT APPEARS THE BEST CHANCES OF SEEING VSBY REDUCTIONS IN -RA ARE ALONG THE KBLF-KBCB-KDAN CORRIDOR AND POINTS SW INTO WEDNESDAY AFTERNOON. THIS SHOULD ALSO BE WHERE MORE IN THE WAY OF CONTINUING IFR TO MVFR CONDITIONS PREVAIL WITH PERHAPS A PERIOD OF VFR AT KLYH WITH KROA MOSTLY MVFR WITH ONLY SPOTTY -RA. MODELS DISAGREE ON HOW FAST THE PRECIP ON WEDNESDAY GETS SHUNTED TO THE SOUTH WITH THE NAM QUITE WET INTO THURSDAY WITH OTHERS SHOWING A BREAK WED NIGHT AND THEN MORE -RA WITH ANOTHER FEATURE ON THURSDAY. EITHER WAY APPEARS OVERALL SUB-VFR WILL BE THE RULE WITH ONLY PERIODIC IMPROVEMENT POSSIBLY OCCURRING ACROSS NORTHERN SECTIONS...AFFECTING THE KLWB-KLYH ROUTE. EXTENDED AVIATION... THE WEDGE REMAINS IN PLACE INTO FRIDAY MORNING WITH CONTINUED IFR TO MVFR CEILINGS AND OCNL MVFR VSBYS IN -RA/DZ/FOG. ON FRIDAY...LOW LEVEL FLOW TURNS TO THE SOUTHWEST IN ADVANCE OF A COLD FRONT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE IN THE AFTERNOON...ESPECIALLY ONCE THE WEDGE BREAKS. ON SATURDAY THE FRONT COMES THROUGH SHOWERS AND THUNDERSTORMS. EXPECTING OCCASIONAL PERIODS OF MVFR CONDITIONS UNTIL THE FRONT PASSES. SUNDAY A DRIER AIR MASS WILL PUSH INTO THE REGION ALONG WITH HIGH PRESSURE BEHIND THE FRONT. THIS IS A SLOWER TIMING THAN THE PAST FEW RUNS OF THE MODELS. ONCE THIS DRIER AIR ARRIVES...CONDITIONS SHOULD IMPROVE BACK TO VFR. && .HYDROLOGY... AS OF 400 AM EDT WEDNESDAY... RUNOFF FROM EARLIER HEAVY RAINFALL OF AROUND 2 INCHES IN SPOTS ACROSS THE GREENBRIER VALLEY AND VIRGINIA HIGHLANDS WILL CONTINUE TO FILTER INTO MAINSTEM WATERWAYS AND RESULT IN NEAR BANKFULL CONDITIONS FOR MANY STREAMS AND CREEKS TODAY. HOWEVER LATEST FORECASTS SUGGEST THAT MOST RIVERS INCLUDING THE GREENBRIER AT ALDERSON AND THE JAMES DOWNSTREAM FROM LICK RUN WILL REMAIN BELOW FLOOD STAGE BASED ON THIS EARLIER RAINFALL. ADDITIONAL RAIN WILL SPREAD BACK ACROSS PARTS OF THE REGION TODAY RESULTING IN ANOTHER HALF TO ONE INCH ACROSS THE MOUNTAINS OF NORTHWEST NORTH CAROLINA AS WELL AS PORTIONS OF SOUTHWEST VIRGINIA. HOWEVER RAINFALL RATES AND FORECASTED QPF SHOULD NOT BE ENOUGH TO CAUSE FLOOD PROBLEMS BUT WILL NEED TO BE WATCHED GIVEN DIFFERING FLASH FLOOD GUIDANCE ACROSS THE REGION. ELSEWHERE TOTALS ARE EXPECTED TO REMAIN RATHER LIGHT WITH TOTALS RANGING FROM A QUARTER/HALF INCH OVER THE SW TO LESS THAN A TENTH OF AN INCH ALONG THE INTERSTATE 64 CORRIDOR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH/WP NEAR TERM...JH SHORT TERM...KK LONG TERM...RCS AVIATION...AMS/JH/MBS HYDROLOGY...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
415 AM EDT WED APR 15 2015 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS THE CAROLINAS TODAY INTO AT LEAST THURSDAY. WEAK WAVES OF LOW PRESSURE RIDING NORTHEAST ALONG THE FRONT WILL COMBINE WITH A STRONG WEDGE OF HIGH PRESSURE TO KEEP COOL AND DAMP CONDITIONS IN PLACE OVER THE NEXT COUPLE OF DAYS. SLIGHTLY WARMER AIR RETURNS BY WEEKS END AHEAD OF ANOTHER COLD FRONT THAT WILL CROSS THE AREA OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 252 AM EDT WEDNESDAY... FRONT NOW WELL TO THE SOUTH REMAINS THE FOCUS FOR ADDED PRECIP CHANCES OVER THE NEXT 24 HOURS AS PIECES OF ENERGY EJECT EAST FROM THE RESIDUAL 5H LOW OVER THE PLAINS AND CAUSE WEAK SURFACE WAVES ALONG THE BOUNDARY. THIS WHILE LOW LEVEL WEDGING ENHANCES ALONG/EAST OF THE MOUNTAINS AS HIGH PRESSURE BUILDS TO THE NORTH AND EVENTUALLY DOWN THE MID ATLANTIC COAST LATER TONIGHT. SQUEEZE PLAY IN BETWEEN THE TWO TO MAKE FOR ADDED PERIODS OF RAIN ESPCLY SOUTHERN HALF TODAY AND ACROSS THE SOUTH AND WEST OVERNIGHT. HOWEVER JUST HOW FAR NORTH SIGNIFICANT RAIN MAKES IT TODAY STILL TRICKY GIVEN DIFFERING MODEL SOLUTIONS ON TIMING OF THE DEVELOPING WEDGE FROM THE NE AND STRENGTH OF OVERRUNNING/DIFFLUENCE ALOFT PER JET AXIS OVERTOP THE CAD THROUGH THE AFTERNOON. LATEST HRRR QUITE WET ACROSS THE REGION BUT APPEARS RATHER FAST AND PERHAPS OVERDONE SIMILAR TO THE NAM...WHILE THE GFS/EC AND HIRES GUIDANCE BRING DEEP MOISTURE INTO THE SOUTH/SW THIS MORNING BEFORE SHUNTING MORE TO THE SE LATER IN THE DAY. SINCE APPEARS OFF THE LATEST OBS/MSAS THAT THE WEDGE IS MAKING SOME INROADS FROM THE NORTH WILL FOLLOW CLOSER TO THE LATEST SREF COMPROMISE AND RAISE POPS TO LIKELY SOUTHERN TIER AND HIGHER CHANCES WEST WITH ONLY LOW TO SLIGHT POPS FAR NE TODAY. DOESN`T APPEAR RAINFALL RATES OR FORECAST QPF WILL BE HIGH ENOUGH TO CAUSE THE NEED FOR ANY FLOOD WATCHES AT THIS TIME OVER THE SW GIVEN LESS UPSLOPE BUT ANOTHER GOOD HALF TO AN INCH POSSIBLE NW NC MOUNTAINS. LEFT TEMPS QUITE COOL GIVEN THE WEDGE UNDER LOW CLOUDS/RAIN WITH HIGHS ONLY RISING A BIT INTO THE 50S...TO PERHAPS AROUND 60 IN SPOTS OVER THE FAR WEST...AND NE WHERE SOME BREAKS IN THE LOW DECK COULD OCCUR AT TIMES. UPPER SUPPORT ELONGATES OUT OVERNIGHT AS THE REGION REMAINS STUCK BETWEEN HIGH PRESSURE NOSING IN FROM THE NE AND RESIDUAL LOW PRESSURE BACK ALONG THE MISSISSIPPI RIVER. THIS SHOULD ALLOW THE FLOW TO BECOME MORE OF A SE UPSLOPE COMPONENT OVER THE SW AS ANOTHER WAVE OF LIFT PUSHES EAST TOWARD THE MOUNTAINS FROM SHORTWAVE ENERGY PASSING WELL TO THE NW. SOME SOLUTIONS ESPCLY THE NAM/EC BASICALLY CONNECT THE AXIS OF DEEPER MOISTURE/LIFT FROM TODAY OVER THE SE TO THE NEXT IMPULSE HEADING IN FROM THE WEST. THIS WOULD KEEP RAIN GOING FROM SE WEST VA ACROSS EXTREME SW VA INTO NW NC FOR MUCH OF THE NIGHT WHILE HAVING THINGS DRY OUT TO SOME DEGREE OVER THE NE. AGAIN THINK THIS IS OVERDONE BUT EXPECT MORE RAIN TO ARRIVE WEST LATE SO UPPED POPS TO HIGHER CHANCE WESTERN HALF...AND KEPT LIKELY/CHANCE GOING SW OVERNIGHT FOR BETTER SE FLOW. LOWS MOSTLY ON THE COOL SIDE WITH 40S MOST SPOTS UNDER THE CAD BY MORNING. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 400 AM EDT WEDNESDAY... UNSETTLED WEATHER WILL CONTINUE INTO THE WEEKEND. A 1033 MB HIGH PRESSURE WILL WEDGE DOWN THE EAST COAST THURSDAY AND WEAKEN AS IT SLIDE EAST THURSDAY NIGHT INTO FRIDAY. MODELS ARE STILL DISPLAYING A SURFACE REFLECTIONS OFF THE SOUTHEAST COAST...WHICH INTENSIFIES INTO A SURFACE LOW AND LIFTS NORTHWARD INTO FRIDAY. THE PRESSURE GRADIENT BETWEEN THE HIGH PRESSURE TO THE NORTH AND LOW PRESSURE TO SOUTH WILL BRING A STRONG FETCH OF ATLANTIC MOISTURE TOWARDS THE SOUTH-CENTRAL APPALACHIANS. MAINTAIN HIGHEST POPS ALONG THE BLUE RIDGE THURSDAY. UNDER PLENTY OF CLOUDS...LEANED TOWARDS THE COOLER MOS FOR HIGH TEMPERATURES THURSDAY WITH READINGS FROM THE UPPER 40S IN THE MOUNTAINS TO THE UPPER 50S IN THE PIEDMONT. FOR THURSDAY NIGHT...LEANED POPS TOWARDS THE NAM WITH HIGHER POPS ALONG THE BLUE RIDGE...THEN TAPERING OFF BY 12Z FRIDAY. LOW TEMPERATURES THURSDAY NIGHT WILL RANGE FROM THE LOWER 40S IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT. ON FRIDAY...THE COASTAL LOW LIFTS NORTH INTO THE ATLANTIC OCEAN...WHILE A WHILE WEAK HIGH PRESSURE DRIFTS OVER THE REGION. A SHORTWAVE WILL ROTATE EAST AROUND THE UPPER TROUGH FRIDAY INTO FRIDAY NIGHT. A WEAK COLD FRONT/SURFACE TROUGH MOVES INTO THE AREA FRIDAY AFTERNOON AND WASHES OUT. HIGH TEMPERATURES ON FRIDAY WILL BE WARMER THAN THURSDAY WITH VALUES VARYING FROM THE UPPER 50S IN THE MOUNTAINS TO LOWER 70S IN THE PIEDMONT. WITH DRIER AIR MOVING IN ALOFT CUT BACK POPS FOR FRIDAY NIGHT TO SLIGHT CHANCE. LOW TEMPERATURES FRIDAY NIGHT WILL DROP INTO THE UPPER 40S IN THE WEST TO THE LOWER TO MID 50S IN THE EAST. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 245 PM EDT TUESDAY... A COLD FRONT IS EXPECTED TO STALL ACROSS THE OHIO VALLEY ON SATURDAY WITH A POSSIBLE CLOSED LOW HOVERING OVER THE OZARKS. THERE WILL REMAIN A GOOD FLOW OF MOISTURE INTO THE REGION FROM THE GULF THROUGH THE WEEKEND TO KEEP HIGH CHANCE POPS. THE MAIN QUESTION REGARDING RAIN IS TIMING. HIGH PRESSURE DRIFTS OVER THE REGION EARLY NEXT WEEK TO BRING AN END TO THE RAIN. WITH MORE CLOUDS AND RAIN IN THE FORECAST...TEMPERATURES WILL BE COOL BUT NOT TO FAR REMOVED FROM NORMAL. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... AS OF 100 AM EDT WEDNESDAY... CIGS HAVE SLOWLY IMPROVED TO AT LEAST MVFR IN MANY LOCATIONS OVERNIGHT WITH THE EXCEPTION OF SPOTS ALONG THE RIDGES WHERE IFR/LIFR IN STRATUS/FOG/DZ PERSISTS. HOWEVER EXPECT ANY BRIEF DRYING BEHIND THE INITIAL EXITING WAVE TO END TOWARD DAYBREAK AS ANOTHER IMPULSE PUSHES DEEPER MOISTURE INCLUDING -RA BACK NE INTO THE AREA. AHEAD OF THIS EXPECTING VARYING CONDITIONS FROM MORE MVFR/IFR IN LOW CLOUDS/FOG OVER THE MOUNTAINS TO PERHAPS MORE HIGH END MVFR FROM KROA AND POINTS EAST AS DRY AIR UNDER HIGH PRESSURE TO THE NORTH WEDGES IN. SQUEEZE PLAY CONTINUES ON WEDNESDAY WITH HIGH PRESSURE STRENGTHENING EAST OF THE BLUE RIDGE AND MOISTURE TRYING TO RIDE IN FROM THE SW WITH THE NEXT IMPULSE. HOW FAR NORTH/NE TO TAKE PRECIP REMAINS LOW CONFIDENCE BUT APPEARS THE BEST CHANCES OF SEEING VSBY REDUCTIONS IN -RA ARE ALONG THE KBLF-KBCB-KDAN CORRIDOR AND POINTS SW INTO WEDNESDAY AFTERNOON. THIS SHOULD ALSO BE WHERE MORE IN THE WAY OF CONTINUING IFR TO MVFR CONDITIONS PREVAIL WITH PERHAPS A PERIOD OF VFR AT KLYH WITH KROA MOSTLY MVFR WITH ONLY SPOTTY -RA. MODELS DISAGREE ON HOW FAST THE PRECIP ON WEDNESDAY GETS SHUNTED TO THE SOUTH WITH THE NAM QUITE WET INTO THURSDAY WITH OTHERS SHOWING A BREAK WED NIGHT AND THEN MORE -RA WITH ANOTHER FEATURE ON THURSDAY. EITHER WAY APPEARS OVERALL SUB-VFR WILL BE THE RULE WITH ONLY PERIODIC IMPROVEMENT POSSIBLY OCCURRING ACROSS NORTHERN SECTIONS...AFFECTING THE KLWB-KLYH ROUTE. EXTENDED AVIATION... THE WEDGE REMAINS IN PLACE INTO FRIDAY MORNING WITH CONTINUED IFR TO MVFR CEILINGS AND OCNL MVFR VSBYS IN -RA/DZ/FOG. ON FRIDAY...LOW LEVEL FLOW TURNS TO THE SOUTHWEST IN ADVANCE OF A COLD FRONT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE IN THE AFTERNOON...ESPECIALLY ONCE THE WEDGE BREAKS. ON SATURDAY THE FRONT COMES THROUGH SHOWERS AND THUNDERSTORMS. EXPECTING OCCASIONAL PERIODS OF MVFR CONDITIONS UNTIL THE FRONT PASSES. SUNDAY A DRIER AIR MASS WILL PUSH INTO THE REGION ALONG WITH HIGH PRESSURE BEHIND THE FRONT. THIS IS A SLOWER TIMING THAN THE PAST FEW RUNS OF THE MODELS. ONCE THIS DRIER AIR ARRIVES...CONDITIONS SHOULD IMPROVE BACK TO VFR. && .HYDROLOGY... AS OF 400 AM EDT WEDNESDAY... RUNOFF FROM EARLIER HEAVY RAINFALL OF AROUND 2 INCHES IN SPOTS ACROSS THE GREENBRIER VALLEY AND VIRGINIA HIGHLANDS WILL CONTINUE TO FILTER INTO MAINSTEM WATERWAYS AND RESULT IN NEAR BANKFULL CONDITIONS FOR MANY STREAMS AND CREEKS TODAY. HOWEVER LATEST FORECASTS SUGGEST THAT MOST RIVERS INCLUDING THE GREENBRIER AT ALDERSON AND THE JAMES DOWNSTREAM FROM LICK RUN WILL REMAIN BELOW FLOOD STAGE BASED ON THIS EARLIER RAINFALL. ADDITIONAL RAIN WILL SPREAD BACK ACROSS PARTS OF THE REGION TODAY RESULTING IN ANOTHER HALF TO ONE INCH ACROSS THE MOUNTAINS OF NORTHWEST NORTH CAROLINA AS WELL AS PORTIONS OF SOUTHWEST VIRGINIA. HOWEVER RAINFALL RATES AND FORECASTED QPF SHOULD NOT BE ENOUGH TO CAUSE FLOOD PROBLEMS BUT WILL NEED TO BE WATCHED GIVEN DIFFERING FLASH FLOOD GUIDANCE ACROSS THE REGION. ELSEWHERE TOTALS ARE EXPECTED TO REMAIN RATHER LIGHT WITH TOTALS RANGING FROM A QUARTER/HALF INCH OVER THE SW TO LESS THAN A TENTH OF AN INCH ALONG THE INTERSTATE 64 CORRIDOR. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH/WP NEAR TERM...JH SHORT TERM...KK LONG TERM...RCS AVIATION...AMS/JH/MBS HYDROLOGY...JH/WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1238 PM CDT WED APR 15 2015 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND THURSDAY ISSUED AT 349 AM CDT WED APR 15 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE STRETCHING FROM HUDSON BAY TO THE OHIO VALLEY. LOW LEVEL WINDS ARE BEGINNING TO SHIFT TO THE EAST OR SOUTHEAST AS THE HIGH DRIFTS ACROSS THE CENTRAL GREAT LAKES. DEWPOINTS HAVE RECOVERED SOMEWHAT...BUT EAGLE RIVER AND ARBOR VITAE HAVE RECENTLY DROPPED BACK INTO THE TEENS...AND PWATS REMAIN AROUND 0.30 INCHES. THIN CIRRUS IS SLOWLY WORKING NORTHWARD AHEAD OF WEAK SHORTWAVES OVER THE CENTRAL PLAINS AND OHIO VALLEY. WITH THE VERY DRY AIRMASS RECIRCULATING OVER THE AREA TODAY...TEMPS/WIND GUSTS/HUMIDITIES REMAIN THE PRIMARY FORECAST CONCERNS. TODAY...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES WILL DRIFT SLOWLY EAST TODAY...BUT STILL REMAIN IN FIRM CONTROL ACROSS THE REGION. WINDS WILL CONTINUE TO SHIFT TO THE EAST OR SOUTHEAST...EMANATING OUT OF THIS DRY SURFACE HIGH...AND OFFER NO REPRIEVE FROM THE VERY DRY CONDITIONS AS OF LATE. ALTHOUGH MIXING HEIGHTS ARE NOT PROJECTED TO BE AS HIGH AS YESTERDAY...STRONGER WINDS ALOFT SHOULD BE ABLE TO TAP INTO THE VERY DRY AIR JUST ABOVE THE INVERSION AND MIX TO THE SURFACE THIS AFTERNOON. PROGGED SOUNDINGS INDICATE GUSTS COULD REACH UP TO AROUND 20 KTS. THESE GUSTS COMBINED WITH TEMPS IN THE MID 60S AND HUMIDITIES IN THE MID TEENS WILL RESULT IN A CRITICAL FIRE WEATHER DAY ACROSS THE REGION. WITH COORDINATION FROM SURROUNDING OFFICES AND THE DNR...WILL UPGRADE THE FIRE WEATHER WATCH INTO A RED FLAG WARNING. OTHERWISE...CIRRUS WILL GRADUALLY INVADE FROM THE SOUTH TO OFFER FILTERED SUNSHINE AT TIMES. TEMPS WILL BE MUCH COOLER NEAR LAKE MICHIGAN. TONIGHT...WEAK SHORTWAVE ENERGY WILL LIFT INTO THE WESTERN GREAT LAKES. WILL CONTINUE TO SEE A VEIL OF THIN CIRRUS OVERHEAD AS MID AND LOW LEVELS REMAIN VERY DRY. DEEPER MOISTURE WILL MAKE A RUN INTO SOUTHERN LAKE MICHIGAN AND LOWER MICHIGAN...BUT LOOKS TOO FAR SOUTHEAST TO HAVE MUCH OF AN IMPACT OVER NORTHEAST WISCONSIN. AS A RESULT...WILL SEE PARTLY CLOUDY SKIES WITH WARMER LOWS RANGING FROM THE MIDDLE 30S NORTH TO THE LOW 40S SOUTH. THURSDAY...DEEP MOISTURE CONTINUES TO FLOW NNE ACROSS THE LOWER PENINSULA OF MICHIGAN AS A WEAK SHORTWAVE SHIFTS TO THE EAST. MEANWHILE...A WEAK COLD FRONT WILL SAG INTO MINNESOTA DURING THE AFTERNOON. WISCONSIN WILL RESIDE BETWEEN THESE FEATURES WITH AN AREA OF VERY DRY LOW AND MID LEVEL AIR REMAINING IN PLACE. THOUGH THE AIR WILL BE MODIFIED...STILL PLENTY OF DRY AIR TO TAP INTO JUST ABOVE THE INVERSION BUT WILL NOT HAVE THE GOOD MECHANICAL MIXING LIKE TODAY. SO WILL HAVE HUMIDITIES FALLING TO AROUND 25 PCT IN THE AFTERNOON...WHICH WILL APPROACH CRITICAL LEVELS. WINDS WILL BE AROUND 5 TO 10 KTS THOUGH SO NOT EXPECTING A REPEAT OF TODAYS CRITICAL VALUES. HIGHS IN THE MID TO UPPER 60S. .LONG TERM...THURSDAY NIGHT THROUGH TUESDAY ISSUED AT 349 AM CDT WED APR 15 2015 ZONAL FLOW EXPECTED EARLY IN THE PERIOD OVER THE GREAT LAKES REGION AS CUT OFF LOW MEANDERS ACROSS THE SOUTHWEST UNITED STATES. BY EARLY IN THE WEEKEND...THE CLOSED LOW OVER THE SOUTHWEST UNITED STATES WILL OPEN UP AND BE PICKED UP BY 500MB TROUGH MOVING ACROSS SOUTHERN CANADA. THE 500MB TROUGH ACROSS CANADA WILL EVOLVE INTO A CLOSED LOW ACROSS SOUTHERN CANADA AND THE WESTERN GREAT LAKES...BRINGING COOLER AND MORE UNSETTLED WEATHER TO THE REGION. FOR FRIDAY...ALTHOUGH DEW POINTS WILL BE ON THE INCREASE...SO WILL TEMPERATURES. AFTERNOON RELATIVE HUMIDITY READINGS SHOULD FALL TO 30 TO 45 PERCENT AT MOST PLACES. FRONTAL BOUNDARY WILL MOVE ACROSS THE REGION DURING THE DAY...BRINGING A CHANCE OF SHOWERS. MODEL SOUNDINGS DID SHOW ENOUGH MOISTURE TO SQUEEZE OUT SOME SHOWERS. IF SHOWERS DO DEVELOP...SOME OF THEM COULD PRODUCE GUSTY WINDS. MODEL SOUNDINGS INDICATED INVERTED V STRUCTURE TO SUPPORT THE GUSTY WINDS. COOLER TEMPERATURES WILL RETURN ON SATURDAY ON NORTHEAST/EAST WINDS. INCREASED MAX TEMPERATURE GRADIENT DUE TO WINDS OFF THE COOLER BAY AND LAKE...WHILE CENTRAL WISCONSIN COULD STILL REACH THE MIDDLE 60S. AGAIN...RELATIVE HUMIDITY READINGS AWAY FROM THE BAY AND LAKE COULD FALL TO 25 TO 35 PERCENT AGAIN. BASED ON THE LATEST MODEL RUNS TONIGHT...SYSTEM FOR SUNDAY/SUNDAY NIGHT IS QUICKER THAN LAST NIGHT. DID INCREASE RAIN CHANCES FOR SUNDAY AFTERNOON WHICH SHOULD LINGER INTO MONDAY. COOLER CYCLONIC FLOW EARLY NEXT WEEK WILL BRING A SMALL CHANCE OF SHOWERS MONDAY NIGHT AND TUESDAY. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1238 PM CDT WED APR 15 2015 VFR CONDITIONS SHOULD PREVAIL THROUGH AT LEAST THURSDAY MORNING. THE ONLY REAL CONCERN IS RAIN ASSOCIATED A SURFACE LOW...MID LEVEL SHORT WAVE ENERGY AND INCREASING LOW LEVEL MOISTURE IN RETURN FLOW AROUND A DEPARTING HIGH. THE 12Z NAM HAD SOME QPF INTO SOUTHERN MANITOWOC AND CALUMET COUNTIES THURSDAY MORNING WHILE THE 12Z GFS...12Z GEM-NH...AND 00Z ECMWF ALL KEPT THE QPF JUST TO THE SOUTH AND EAST OF THE FORECAST AREA. BASED ON THE DRY 12Z GRB AND CENTRAL ILLINOIS SOUNDINGS IT WOULD SEEM LIKE A DRY FORECAST WOULD BE THE BETTER ROUTE...BUT THE 12Z NASHVILLE SOUNDING WAS SATURATED SO THERE IS SOME UNCERTAINTY WITH THIS FORECAST. POTENTIAL FOR RAIN AND LOW CIGS/VSBYS SEEMS TOO LOW TO INCLUDE IN MTW TAF. && .GRB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR WIZ030-035>037- 045. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......MG
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1003 AM CDT WED APR 15 2015 .UPDATE... A RED FLAG WARNING REMAINS IN EFFECT FROM NOON TO 8 PM CDT FOR OUR NORTHWESTERN COUNTIES. AREA OF HIGH PRESSURE IS SLOWLY MOVING EAST OF THE REGION...WHICH SHOULD STAVE OFF ANY PRECIPITATION DURING THE DAY TODAY. DEW POINTS WILL ONCE AGAIN FALL LATER THIS MORNING AND AFTERNOON AS DIURNAL HEATING RAMPS UP...BUT THEY SHOULD NOT FALL QUITE AS FAR AS THEY DID TUESDAY AS RAP BUFKIT SOUNDINGS INDICATE BOUNDARY LAYER MIXING ONLY TO 850MB...NOT QUITE AS DEEP OF MIXING AS WE SAW TUESDAY. GUSTY EAST-SOUTHEAST WINDS TODAY WILL KEEP TEMPERATURES COOLER ALONG THE LAKE MI SHORE COMPARED TO FURTHER INLAND...WITH HIGHS NEAR THE LAKE SHORE IN THE UPPER 50S TO NEAR 60. TEMPERATURES WILL BE IN THE MID TO UPPER 60S FURTHER INLAND. .AVIATION/18Z TAFS/... VFR CONDITIONS WILL CONTINUE ACROSS THE TAF SITES...ALTHOUGH WINDS WILL BE GUSTY FROM THE EAST-SOUTHEAST...ESPECIALLY THIS AFTERNOON. GUSTS WILL BE STRONGER FOR MSN AND UES AS THE PRESSURE GRADIENT SHOULD BE TIGHTER FURTHER INLAND FROM LAKE MICHIGAN...ACCORDING TO HIGH-RES SHORT-TERM GUIDANCE. GUSTS MAY REACH NEAR 20KTS THIS AFTERNOON FOR MSN AND UES...WHILE ENW AND MKE WILL SEE WEAKER WINDS AS THE PRESSURE GRADIENT IS NOT AS STRONG NEAR THE LAKESHORE. MAINLY HIGH LEVEL CIRRUS AND STRATUS CLOUDS WILL PERSIST ACROSS THE AREA THIS AFTERNOON. .PREV DISCUSSION... /ISSUED 344 AM CDT WED APR 15 2015/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH. THE ATMOSPHERE REMAINS BONE DRY TODAY...BUT WE SHOULDN/T MIX OUT THE DEWPOINTS AS READILY AS WE DID ON TUESDAY. THE SURFACE HIGH HAS SHIFTED OFF TO THE EAST...SO WE/LL GET INTO A BIT MORE OF A RETURN FLOW...BUT IT/S MOSTLY EASTERLY. STILL...DEWPOINTS WILL BE A BIT MORE ELEVATED THAN YESTERDAY. HIGH CLOUDS WILL BE INCREASING ACROSS THE REGION AS A MID LEVEL TROF MOVES IN FROM THE SOUTHWEST. IT/S A DECENT SHORT WAVE...BUT GIVEN HOW DRY THE LOWER HALF OF THE TROP IS...NO PRECIP IS EXPECTED. THE ONE POSSIBLE CAVEAT IS THE FAR SOUTHEAST LATE TONIGHT...TOWARD SUNRISE. THE MODELS SHOW DEEPER MOISTURE SNEAKING UP ACROSS EASTERN IL INTO LOWER MICHIGAN. A STRAY SHOWER COULD CLIP THE FAR SOUTHEAST...WORTHY OF A SLIGHT CHANCE OF A SHOWER ACROSS KENOSHA/RACINE COUNTIES TEMPS TODAY WILL BE A NOTCH LOWER THAN YESTERDAY GIVEN THE STRONGER EASTERLY FLOW AND THE COOLING INFLUENCE OF LAKE MICHIGAN. THAT MEANS FOLKS NEAR THE LAKE WILL FEEL ESPECIALLY COOL TODAY. THURSDAY AND THURSDAY NIGHT...FORECAST CONFIDENCE HIGH. DRY AIR AND SURFACE HIGH PRESSURE WILL CONTINUE TO DOMINATE SOUTHERN WI THROUGH THU NIGHT. A MID LEVEL SHORTWAVE TRACKING THROUGH THE GREAT LAKES WILL HAVE SOME RESIDUAL CLOUD COVER IN SOUTHERN WI DURING THE MORNING HOURS. THE PRESSURE GRADIENT WILL BE WEAK ACROSS THE AREA ON THU... SO EXPECT A LAKE BREEZE TO DEVELOP AND PUSH INLAND LATE IN THE AFTERNOON. INLAND HIGHS WILL BE IN THE UPPER 60S WITH A FEW LOCATIONS MAYBE REACHING 70 IN THE WESTERN FORECAST AREA WITH SKIES CLEARING OUT AND LIGHT WINDS DURING THE AFTERNOON. DEWPOINT TEMPERATURES WILL IN THE 30S WITH MINIMUM RH VALUES ON THE LOW SIDE ONCE AGAIN... ALTHOUGH NOT QUITE AS LOW AS TUE AND WED THIS WEEK. LONG TERM... FRIDAY... FORECAST CONFIDENCE MEDIUM. A SHORTWAVE DROPPING THROUGH LAKE SUPERIOR AND AN ASSOCIATED SURFACE TROUGH WILL BRING A CHANCE FOR SHOWERS TO SOUTHERN WI FRI AFTERNOON OR MAYBE THE EVENING. THE NAM IS THE ONLY MODEL PRODUCING QPF BUT OTHER MODELS SHOW THE POTENTIAL FOR A FEW LIGHT SHOWERS OR SPRINKLES. OTHERWISE... PLAN ON HIGHS REACHING INTO THE LOWER 70S INLAND AND 60S NEAR THE SHORELINE AHEAD OF THAT SURFACE TROUGH. WINDS WILL BE FAIRLY LIGHT SO OVERALL IT WILL BE A NICE DAY. SATURDAY THROUGH MONDAY... FORECAST CONFIDENCE MEDIUM. SATURDAY WILL BE COOLER WITH AN INCREASING NORTHEAST BREEZE DURING THE AFTERNOON. PLENTY OF DRY AIR WITH THE SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING WILL ALLOW FOR SUNSHINE. MODELS ARE COMING INTO BETTER AGREEMENT NOW WITH EJECTING THE CLOSED UPPER LOW OVER THE SOUTHWEST INTO THE PLAINS SATURDAY NIGHT AND PHASING IT WITH A SHORTWAVE TROUGH CROSSING SOUTHERN CANADA AS IT REACHES THE UPPER MIDWEST ON SUNDAY. THIS WILL BRING AN INCREASING CHANCE FOR SHOWERS TO SOUTHERN WI ON SUNDAY THROUGH MONDAY. TUESDAY THROUGH WEDNESDAY... FORECAST CONFIDENCE MEDIUM. THAT SHORTWAVE TROUGH WILL EVOLVE INTO A CLOSED UPPER LOW OVER THE UPPER MIDWEST/UPPER GREAT LAKES AREA EARLY NEXT WEEK. THIS WILL USHER COLDER AIR INTO SOUTHERN WI. BOTH THE GFS AND ECMWF SHOW 850MB TEMPS DROPPING BELOW 0C BY MID WEEK. SHORTWAVES ROTATING AROUND THE UPPER LOW MAY PRODUCE LIGHT SHOWERS OVER THE AREA. THE TEMPERATURE PROFILE MAY BE COLD ENOUGH FOR A FEW SNOW SHOWERS. HIGHS WILL BE IN THE 50S AND LOWS WILL BE IN THE 30S. AVIATION/12Z TAFS/... VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD WITH INCREASING MID TO HIGH LEVEL CLOUDS. WINDS WILL BE STABLE OUT OF THE EAST AND A BIT BREEZY/GUSTY DURING THE AFTERNOON...13-20KTS. FIRE WEATHER... ANOTHER VERY DRY DAY EXPECTED ACROSS SOUTHERN WISCONSIN. DEWPOINTS WILL LIKELY MIX OUT INTO THE LOWER 20S...POSSIBLY UPPER TEENS. AN EASTERLY FLOW WILL KEEP DEWPOINTS ELEVATED FOR THOSE COUNTIES BORDERING LAKE MICHIGAN. RELATIVE HUMIDITIES IN THE MIXED OUT AREAS WILL LIKELY DROP TO 15 TO 20 PERCENT. WE SHOULDN/T BE QUITE AS DRY AS YESTERDAY DUE TO MORE MOISTURE WORKING INTO THE AREA DUE TO A RETURN FLOW ON THE BACK SIDE OF A RETREATING SURFACE HIGH PRESSURE. THOSE EASTERLY WINDS WILL BE PUSHING 15 TO 20 MPH THIS AFTERNOON. AFTER COORDINATION WITH THE WI DNR WE WILL BE UPGRADING THE FIRE WATCH TO A RED FLAG WARNING INTO EARLY THIS EVENING. ADDITIONALLY...WE/LL BE ADDING GREEN LAKE AND DANE COUNTIES. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR WIZ046-047-056- 057-062-063-067. LM...NONE. && $$ UPDATE...JTS TODAY/TONIGHT AND AVIATION/MARINE...DAVIS THURSDAY THROUGH TUESDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1000 AM CDT WED APR 15 2015 .UPDATE... A RED FLAG WARNING REMAINS IN EFFECT FROM NOON TO 8 PM CDT FOR OUR NORTHWESTERN COUNTIES. AREA OF HIGH PRESSURE IS SLOWLY MOVING EAST OF THE REGION...WHICH SHOULD STAVE OFF ANY PRECIPITATION DURING THE DAY TODAY. DEW POINTS WILL ONCE AGAIN FALL LATER THIS MORNING AND AFTERNOON AS DIURNAL HEATING RAMPS UP...BUT THEY SHOULD NOT FALL QUITE AS FAR AS THEY DID TUESDAY AS RAP BUFKIT SOUNDINGS INDICATE BOUNDARY LAYER MIXING ONLY TO 850MB...NOT QUITE AS DEEP OF MIXING AS WE SAW TUESDAY. GUSTY EAST-SOUTHEAST WINDS TODAY WILL KEEP TEMPERATURES COOLER ALONG THE LAKE MI SHORE COMPARED TO FURTHER INLAND...WITH HIGHS NEAR THE LAKE SHORE IN THE UPPER 50S TO NEAR 60. TEMPERATURES WILL BE IN THE MID TO UPPER 60S FURTHER INLAND. && .AVIATION/18Z TAFS/... VFR CONDITIONS WILL CONTINUE ACROSS THE TAF SITES...ALTHOUGH WINDS WILL BE GUSTY FROM THE EAST-SOUTHEAST...ESPECIALLY THIS AFTERNOON. GUSTS WILL BE STRONGER FOR MSN AND UES AS THE PRESSURE GRADIENT SHOULD BE TIGHTER FURTHER INLAND FROM LAKE MICHIGAN...ACCORDING TO HIGH-RES SHORT-TERM GUIDANCE. GUSTS MAY REACH NEAR 20KTS THIS AFTERNOON FOR MSN AND UES...WHILE ENW AND MKE WILL SEE WEAKER WINDS AS THE PRESSURE GRADIENT IS NOT AS STRONG NEAR THE LAKESHORE. MAINLY HIGH LEVEL CIRRUS AND STRATUS CLOUDS WILL PERSIST ACROSS THE AREA THIS AFTERNOON. && .PREV DISCUSSION... /ISSUED 344 AM CDT WED APR 15 2015/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH. THE ATMOSPHERE REMAINS BONE DRY TODAY...BUT WE SHOULDN/T MIX OUT THE DEWPOINTS AS READILY AS WE DID ON TUESDAY. THE SURFACE HIGH HAS SHIFTED OFF TO THE EAST...SO WE/LL GET INTO A BIT MORE OF A RETURN FLOW...BUT IT/S MOSTLY EASTERLY. STILL...DEWPOINTS WILL BE A BIT MORE ELEVATED THAN YESTERDAY. HIGH CLOUDS WILL BE INCREASING ACROSS THE REGION AS A MID LEVEL TROF MOVES IN FROM THE SOUTHWEST. IT/S A DECENT SHORT WAVE...BUT GIVEN HOW DRY THE LOWER HALF OF THE TROP IS...NO PRECIP IS EXPECTED. THE ONE POSSIBLE CAVEAT IS THE FAR SOUTHEAST LATE TONIGHT...TOWARD SUNRISE. THE MODELS SHOW DEEPER MOISTURE SNEAKING UP ACROSS EASTERN IL INTO LOWER MICHIGAN. A STRAY SHOWER COULD CLIP THE FAR SOUTHEAST...WORTHY OF A SLIGHT CHANCE OF A SHOWER ACROSS KENOSHA/RACINE COUNTIES TEMPS TODAY WILL BE A NOTCH LOWER THAN YESTERDAY GIVEN THE STRONGER EASTERLY FLOW AND THE COOLING INFLUENCE OF LAKE MICHIGAN. THAT MEANS FOLKS NEAR THE LAKE WILL FEEL ESPECIALLY COOL TODAY. THURSDAY AND THURSDAY NIGHT...FORECAST CONFIDENCE HIGH. DRY AIR AND SURFACE HIGH PRESSURE WILL CONTINUE TO DOMINATE SOUTHERN WI THROUGH THU NIGHT. A MID LEVEL SHORTWAVE TRACKING THROUGH THE GREAT LAKES WILL HAVE SOME RESIDUAL CLOUD COVER IN SOUTHERN WI DURING THE MORNING HOURS. THE PRESSURE GRADIENT WILL BE WEAK ACROSS THE AREA ON THU... SO EXPECT A LAKE BREEZE TO DEVELOP AND PUSH INLAND LATE IN THE AFTERNOON. INLAND HIGHS WILL BE IN THE UPPER 60S WITH A FEW LOCATIONS MAYBE REACHING 70 IN THE WESTERN FORECAST AREA WITH SKIES CLEARING OUT AND LIGHT WINDS DURING THE AFTERNOON. DEWPOINT TEMPERATURES WILL IN THE 30S WITH MINIMUM RH VALUES ON THE LOW SIDE ONCE AGAIN... ALTHOUGH NOT QUITE AS LOW AS TUE AND WED THIS WEEK. LONG TERM... FRIDAY... FORECAST CONFIDENCE MEDIUM. A SHORTWAVE DROPPING THROUGH LAKE SUPERIOR AND AN ASSOCIATED SURFACE TROUGH WILL BRING A CHANCE FOR SHOWERS TO SOUTHERN WI FRI AFTERNOON OR MAYBE THE EVENING. THE NAM IS THE ONLY MODEL PRODUCING QPF BUT OTHER MODELS SHOW THE POTENTIAL FOR A FEW LIGHT SHOWERS OR SPRINKLES. OTHERWISE... PLAN ON HIGHS REACHING INTO THE LOWER 70S INLAND AND 60S NEAR THE SHORELINE AHEAD OF THAT SURFACE TROUGH. WINDS WILL BE FAIRLY LIGHT SO OVERALL IT WILL BE A NICE DAY. SATURDAY THROUGH MONDAY... FORECAST CONFIDENCE MEDIUM. SATURDAY WILL BE COOLER WITH AN INCREASING NORTHEAST BREEZE DURING THE AFTERNOON. PLENTY OF DRY AIR WITH THE SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING WILL ALLOW FOR SUNSHINE. MODELS ARE COMING INTO BETTER AGREEMENT NOW WITH EJECTING THE CLOSED UPPER LOW OVER THE SOUTHWEST INTO THE PLAINS SATURDAY NIGHT AND PHASING IT WITH A SHORTWAVE TROUGH CROSSING SOUTHERN CANADA AS IT REACHES THE UPPER MIDWEST ON SUNDAY. THIS WILL BRING AN INCREASING CHANCE FOR SHOWERS TO SOUTHERN WI ON SUNDAY THROUGH MONDAY. TUESDAY THROUGH WEDNESDAY... FORECAST CONFIDENCE MEDIUM. THAT SHORTWAVE TROUGH WILL EVOLVE INTO A CLOSED UPPER LOW OVER THE UPPER MIDWEST/UPPER GREAT LAKES AREA EARLY NEXT WEEK. THIS WILL USHER COLDER AIR INTO SOUTHERN WI. BOTH THE GFS AND ECMWF SHOW 850MB TEMPS DROPPING BELOW 0C BY MID WEEK. SHORTWAVES ROTATING AROUND THE UPPER LOW MAY PRODUCE LIGHT SHOWERS OVER THE AREA. THE TEMPERATURE PROFILE MAY BE COLD ENOUGH FOR A FEW SNOW SHOWERS. HIGHS WILL BE IN THE 50S AND LOWS WILL BE IN THE 30S. AVIATION/12Z TAFS/... VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD WITH INCREASING MID TO HIGH LEVEL CLOUDS. WINDS WILL BE STABLE OUT OF THE EAST AND A BIT BREEZY/GUSTY DURING THE AFTERNOON...13-20KTS. FIRE WEATHER... ANOTHER VERY DRY DAY EXPECTED ACROSS SOUTHERN WISCONSIN. DEWPOINTS WILL LIKELY MIX OUT INTO THE LOWER 20S...POSSIBLY UPPER TEENS. AN EASTERLY FLOW WILL KEEP DEWPOINTS ELEVATED FOR THOSE COUNTIES BORDERING LAKE MICHIGAN. RELATIVE HUMIDITIES IN THE MIXED OUT AREAS WILL LIKELY DROP TO 15 TO 20 PERCENT. WE SHOULDN/T BE QUITE AS DRY AS YESTERDAY DUE TO MORE MOISTURE WORKING INTO THE AREA DUE TO A RETURN FLOW ON THE BACK SIDE OF A RETREATING SURFACE HIGH PRESSURE. THOSE EASTERLY WINDS WILL BE PUSHING 15 TO 20 MPH THIS AFTERNOON. AFTER COORDINATION WITH THE WI DNR WE WILL BE UPGRADING THE FIRE WATCH TO A RED FLAG WARNING INTO EARLY THIS EVENING. ADDITIONALLY...WE/LL BE ADDING GREEN LAKE AND DANE COUNTIES. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR WIZ046-047-056-057-062-063-067. LM...NONE. && $$ UPDATE...JTS TODAY/TONIGHT AND AVIATION/MARINE...DAVIS THURSDAY THROUGH TUESDAY...MRC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
600 AM CDT WED APR 15 2015 UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND THURSDAY ISSUED AT 349 AM CDT WED APR 15 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE STRETCHING FROM HUDSON BAY TO THE OHIO VALLEY. LOW LEVEL WINDS ARE BEGINNING TO SHIFT TO THE EAST OR SOUTHEAST AS THE HIGH DRIFTS ACROSS THE CENTRAL GREAT LAKES. DEWPOINTS HAVE RECOVERED SOMEWHAT...BUT EAGLE RIVER AND ARBOR VITAE HAVE RECENTLY DROPPED BACK INTO THE TEENS...AND PWATS REMAIN AROUND 0.30 INCHES. THIN CIRRUS IS SLOWLY WORKING NORTHWARD AHEAD OF WEAK SHORTWAVES OVER THE CENTRAL PLAINS AND OHIO VALLEY. WITH THE VERY DRY AIRMASS RECIRCULATING OVER THE AREA TODAY...TEMPS/WIND GUSTS/HUMIDITIES REMAIN THE PRIMARY FORECAST CONCERNS. TODAY...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES WILL DRIFT SLOWLY EAST TODAY...BUT STILL REMAIN IN FIRM CONTROL ACROSS THE REGION. WINDS WILL CONTINUE TO SHIFT TO THE EAST OR SOUTHEAST...EMANATING OUT OF THIS DRY SURFACE HIGH...AND OFFER NO REPRIEVE FROM THE VERY DRY CONDITIONS AS OF LATE. ALTHOUGH MIXING HEIGHTS ARE NOT PROJECTED TO BE AS HIGH AS YESTERDAY...STRONGER WINDS ALOFT SHOULD BE ABLE TO TAP INTO THE VERY DRY AIR JUST ABOVE THE INVERSION AND MIX TO THE SURFACE THIS AFTERNOON. PROGGED SOUNDINGS INDICATE GUSTS COULD REACH UP TO AROUND 20 KTS. THESE GUSTS COMBINED WITH TEMPS IN THE MID 60S AND HUMIDITIES IN THE MID TEENS WILL RESULT IN A CRITICAL FIRE WEATHER DAY ACROSS THE REGION. WITH COORDINATION FROM SURROUNDING OFFICES AND THE DNR...WILL UPGRADE THE FIRE WEATHER WATCH INTO A RED FLAG WARNING. OTHERWISE...CIRRUS WILL GRADUALLY INVADE FROM THE SOUTH TO OFFER FILTERED SUNSHINE AT TIMES. TEMPS WILL BE MUCH COOLER NEAR LAKE MICHIGAN. TONIGHT...WEAK SHORTWAVE ENERGY WILL LIFT INTO THE WESTERN GREAT LAKES. WILL CONTINUE TO SEE A VEIL OF THIN CIRRUS OVERHEAD AS MID AND LOW LEVELS REMAIN VERY DRY. DEEPER MOISTURE WILL MAKE A RUN INTO SOUTHERN LAKE MICHIGAN AND LOWER MICHIGAN...BUT LOOKS TOO FAR SOUTHEAST TO HAVE MUCH OF AN IMPACT OVER NORTHEAST WISCONSIN. AS A RESULT...WILL SEE PARTLY CLOUDY SKIES WITH WARMER LOWS RANGING FROM THE MIDDLE 30S NORTH TO THE LOW 40S SOUTH. THURSDAY...DEEP MOISTURE CONTINUES TO FLOW NNE ACROSS THE LOWER PENINSULA OF MICHIGAN AS A WEAK SHORTWAVE SHIFTS TO THE EAST. MEANWHILE...A WEAK COLD FRONT WILL SAG INTO MINNESOTA DURING THE AFTERNOON. WISCONSIN WILL RESIDE BETWEEN THESE FEATURES WITH AN AREA OF VERY DRY LOW AND MID LEVEL AIR REMAINING IN PLACE. THOUGH THE AIR WILL BE MODIFIED...STILL PLENTY OF DRY AIR TO TAP INTO JUST ABOVE THE INVERSION BUT WILL NOT HAVE THE GOOD MECHANICAL MIXING LIKE TODAY. SO WILL HAVE HUMIDITIES FALLING TO AROUND 25 PCT IN THE AFTERNOON...WHICH WILL APPROACH CRITICAL LEVELS. WINDS WILL BE AROUND 5 TO 10 KTS THOUGH SO NOT EXPECTING A REPEAT OF TODAYS CRITICAL VALUES. HIGHS IN THE MID TO UPPER 60S. .LONG TERM...THURSDAY NIGHT THROUGH TUESDAY ISSUED AT 349 AM CDT WED APR 15 2015 ZONAL FLOW EXPECTED EARLY IN THE PERIOD OVER THE GREAT LAKES REGION AS CUT OFF LOW MEANDERS ACROSS THE SOUTHWEST UNITED STATES. BY EARLY IN THE WEEKEND...THE CLOSED LOW OVER THE SOUTHWEST UNITED STATES WILL OPEN UP AND BE PICKED UP BY 500MB TROUGH MOVING ACROSS SOUTHERN CANADA. THE 500MB TROUGH ACROSS CANADA WILL EVOLVE INTO A CLOSED LOW ACROSS SOUTHERN CANADA AND THE WESTERN GREAT LAKES...BRINGING COOLER AND MORE UNSETTLED WEATHER TO THE REGION. FOR FRIDAY...ALTHOUGH DEW POINTS WILL BE ON THE INCREASE...SO WILL TEMPERATURES. AFTERNOON RELATIVE HUMIDITY READINGS SHOULD FALL TO 30 TO 45 PERCENT AT MOST PLACES. FRONTAL BOUNDARY WILL MOVE ACROSS THE REGION DURING THE DAY...BRINGING A CHANCE OF SHOWERS. MODEL SOUNDINGS DID SHOW ENOUGH MOISTURE TO SQUEEZE OUT SOME SHOWERS. IF SHOWERS DO DEVELOP...SOME OF THEM COULD PRODUCE GUSTY WINDS. MODEL SOUNDINGS INDICATED INVERTED V STRUCTURE TO SUPPORT THE GUSTY WINDS. COOLER TEMPERATURES WILL RETURN ON SATURDAY ON NORTHEAST/EAST WINDS. INCREASED MAX TEMPERATURE GRADIENT DUE TO WINDS OFF THE COOLER BAY AND LAKE...WHILE CENTRAL WISCONSIN COULD STILL REACH THE MIDDLE 60S. AGAIN...RELATIVE HUMIDITY READINGS AWAY FROM THE BAY AND LAKE COULD FALL TO 25 TO 35 PERCENT AGAIN. BASED ON THE LATEST MODEL RUNS TONIGHT...SYSTEM FOR SUNDAY/SUNDAY NIGHT IS QUICKER THAN LAST NIGHT. DID INCREASE RAIN CHANCES FOR SUNDAY AFTERNOON WHICH SHOULD LINGER INTO MONDAY. COOLER CYCLONIC FLOW EARLY NEXT WEEK WILL BRING A SMALL CHANCE OF SHOWERS MONDAY NIGHT AND TUESDAY. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 600 AM CDT WED APR 15 2015 SOUTHEAST WINDS WILL BECOME GUSTY LATE THIS MORNING THROUGH THE AFTERNOON. OTHERWISE...GOOD FLYING WEATHER WILL BE PRESENT INTO THURSDAY. && .GRB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR WIZ030-035>037-045. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......MPC
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND THURSDAY ISSUED AT 349 AM CDT WED APR 15 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE STRETCHING FROM HUDSON BAY TO THE OHIO VALLEY. LOW LEVEL WINDS ARE BEGINNING TO SHIFT TO THE EAST OR SOUTHEAST AS THE HIGH DRIFTS ACROSS THE CENTRAL GREAT LAKES. DEWPOINTS HAVE RECOVERED SOMEWHAT...BUT EAGLE RIVER AND ARBOR VITAE HAVE RECENTLY DROPPED BACK INTO THE TEENS...AND PWATS REMAIN AROUND 0.30 INCHES. THIN CIRRUS IS SLOWLY WORKING NORTHWARD AHEAD OF WEAK SHORTWAVES OVER THE CENTRAL PLAINS AND OHIO VALLEY. WITH THE VERY DRY AIRMASS RECIRCULATING OVER THE AREA TODAY...TEMPS/WIND GUSTS/HUMIDITIES REMAIN THE PRIMARY FORECAST CONCERNS. TODAY...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES WILL DRIFT SLOWLY EAST TODAY...BUT STILL REMAIN IN FIRM CONTROL ACROSS THE REGION. WINDS WILL CONTINUE TO SHIFT TO THE EAST OR SOUTHEAST...EMANATING OUT OF THIS DRY SURFACE HIGH...AND OFFER NO REPRIEVE FROM THE VERY DRY CONDITIONS AS OF LATE. ALTHOUGH MIXING HEIGHTS ARE NOT PROJECTED TO BE AS HIGH AS YESTERDAY...STRONGER WINDS ALOFT SHOULD BE ABLE TO TAP INTO THE VERY DRY AIR JUST ABOVE THE INVERSION AND MIX TO THE SURFACE THIS AFTERNOON. PROGGED SOUNDINGS INDICATE GUSTS COULD REACH UP TO AROUND 20 KTS. THESE GUSTS COMBINED WITH TEMPS IN THE MID 60S AND HUMIDITIES IN THE MID TEENS WILL RESULT IN A CRITICAL FIRE WEATHER DAY ACROSS THE REGION. WITH COORDINATION FROM SURROUNDING OFFICES AND THE DNR...WILL UPGRADE THE FIRE WEATHER WATCH INTO A RED FLAG WARNING. OTHERWISE...CIRRUS WILL GRADUALLY INVADE FROM THE SOUTH TO OFFER FILTERED SUNSHINE AT TIMES. TEMPS WILL BE MUCH COOLER NEAR LAKE MICHIGAN. TONIGHT...WEAK SHORTWAVE ENERGY WILL LIFT INTO THE WESTERN GREAT LAKES. WILL CONTINUE TO SEE A VEIL OF THIN CIRRUS OVERHEAD AS MID AND LOW LEVELS REMAIN VERY DRY. DEEPER MOISTURE WILL MAKE A RUN INTO SOUTHERN LAKE MICHIGAN AND LOWER MICHIGAN...BUT LOOKS TOO FAR SOUTHEAST TO HAVE MUCH OF AN IMPACT OVER NORTHEAST WISCONSIN. AS A RESULT...WILL SEE PARTLY CLOUDY SKIES WITH WARMER LOWS RANGING FROM THE MIDDLE 30S NORTH TO THE LOW 40S SOUTH. THURSDAY...DEEP MOISTURE CONTINUES TO FLOW NNE ACROSS THE LOWER PENINSULA OF MICHIGAN AS A WEAK SHORTWAVE SHIFTS TO THE EAST. MEANWHILE...A WEAK COLD FRONT WILL SAG INTO MINNESOTA DURING THE AFTERNOON. WISCONSIN WILL RESIDE BETWEEN THESE FEATURES WITH AN AREA OF VERY DRY LOW AND MID LEVEL AIR REMAINING IN PLACE. THOUGH THE AIR WILL BE MODIFIED...STILL PLENTY OF DRY AIR TO TAP INTO JUST ABOVE THE INVERSION BUT WILL NOT HAVE THE GOOD MECHANICAL MIXING LIKE TODAY. SO WILL HAVE HUMIDITIES FALLING TO AROUND 25 PCT IN THE AFTERNOON...WHICH WILL APPROACH CRITICAL LEVELS. WINDS WILL BE AROUND 5 TO 10 KTS THOUGH SO NOT EXPECTING A REPEAT OF TODAYS CRITICAL VALUES. HIGHS IN THE MID TO UPPER 60S. .LONG TERM...THURSDAY NIGHT THROUGH TUESDAY ISSUED AT 349 AM CDT WED APR 15 2015 ZONAL FLOW EXPECTED EARLY IN THE PERIOD OVER THE GREAT LAKES REGION AS CUT OFF LOW MEANDERS ACROSS THE SOUTHWEST UNITED STATES. BY EARLY IN THE WEEKEND...THE CLOSED LOW OVER THE SOUTHWEST UNITED STATES WILL OPEN UP AND BE PICKED UP BY 500MB TROUGH MOVING ACROSS SOUTHERN CANADA. THE 500MB TROUGH ACROSS CANADA WILL EVOLVE INTO A CLOSED LOW ACROSS SOUTHERN CANADA AND THE WESTERN GREAT LAKES...BRINGING COOLER AND MORE UNSETTLED WEATHER TO THE REGION. FOR FRIDAY...ALTHOUGH DEW POINTS WILL BE ON THE INCREASE...SO WILL TEMPERATURES. AFTERNOON RELATIVE HUMIDITY READINGS SHOULD FALL TO 30 TO 45 PERCENT AT MOST PLACES. FRONTAL BOUNDARY WILL MOVE ACROSS THE REGION DURING THE DAY...BRINGING A CHANCE OF SHOWERS. MODEL SOUNDINGS DID SHOW ENOUGH MOISTURE TO SQUEEZE OUT SOME SHOWERS. IF SHOWERS DO DEVELOP...SOME OF THEM COULD PRODUCE GUSTY WINDS. MODEL SOUNDINGS INDICATED INVERTED V STRUCTURE TO SUPPORT THE GUSTY WINDS. COOLER TEMPERATURES WILL RETURN ON SATURDAY ON NORTHEAST/EAST WINDS. INCREASED MAX TEMPERATURE GRADIENT DUE TO WINDS OFF THE COOLER BAY AND LAKE...WHILE CENTRAL WISCONSIN COULD STILL REACH THE MIDDLE 60S. AGAIN...RELATIVE HUMIDITY READINGS AWAY FROM THE BAY AND LAKE COULD FALL TO 25 TO 35 PERCENT AGAIN. BASED ON THE LATEST MODEL RUNS TONIGHT...SYSTEM FOR SUNDAY/SUNDAY NIGHT IS QUICKER THAN LAST NIGHT. DID INCREASE RAIN CHANCES FOR SUNDAY AFTERNOON WHICH SHOULD LINGER INTO MONDAY. COOLER CYCLONIC FLOW EARLY NEXT WEEK WILL BRING A SMALL CHANCE OF SHOWERS MONDAY NIGHT AND TUESDAY. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 948 PM CDT TUE APR 14 2015 VFR CONDITIONS TO PREVAIL TONIGHT AND WEDNESDAY. && .GRB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR WIZ030-035>037-045. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
241 AM PDT Fri Apr 17 2015 .Synopsis... Very warm temperatures through the weekend. A weak weather system will bring a slight chance of mountain showers or an isolated thundertorm this weekend. Temperatures then start cooling Monday through Wednesday with a chance of rain most areas. && .Discussion... Very little change to previous forecast. Very warm conditions will continue today through Sunday. A weak upper disturbance will move into the area this weekend. It will bring some instability with it for just a slight chance of mainly afternoon and evening showers or a thunderstorm both Saturday and Sunday. Troughing still forecast to start carving out over the area on Monday which will allow temperatures to begin cooling. Moisture chances Monday look to remain only in the higher terrain. Rasch .Extended Discussion (Tuesday through Friday) Mid range models zeroing in on idea of bringing weak Pacific trough onto the coast around Tuesday although ECMWF and GEM still have trough axis slightly offshore Tuesday afternoon. Rather limited moisture with this system will limit precipitation mainly to the mountain areas. GFS shows enough instability with this system Tuesday afternoon to warrant slight thunderstorm threat as well. Models all now pretty much centering the upper trough over the west coast by Wednesday morning so entire CWA has at least a slight threat of showers throughout the day Wednesday. GFS shows most of the instability has moved into Nevada by Wednesday but still somewhat borderline over central California so may need to readdress thunderstorm threat for Wednesday as we get closer. Weather change that appears fairly certain is the significant cool off expected Tuesday and Wednesday. Forecast highs between Monday and Wednesday showing a drop of anywhere from 15 to 20 degrees so this change will be quite noticeable with highs dropping to around normal for this time of year by mid week. Models vary a bit on positioning of low/trough on Thursday but whichever solution verifies...cyclonic flow over the region should continue the shower threat CWA wide. Extended models showing a transition to northerly flow aloft over the north state by Friday as upper system shifts into the Great Basin. As a result...shower threat shifts eastward with main precipitation threat from RAP around moisture over the Sierra. Daytime temperatures rebound a bit but still close to normal compared to very warm temperatures expected early in the week. && .Aviation... VFR conditions next 24 hours. Isolated thunderstorms possible over the mountains after 18z Saturday. Winds generally below 15 knots except in vicinity of thunderstorms. && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1141 PM MDT THU APR 16 2015 .UPDATE... ISSUED AT 930 PM MDT THU APR 16 2015 UPDATED TO MAKE SOME MINOR ADJUSTMENTS TO POPS THROUGH TOMORROW BASED ON RADAR TRENDS AND 00Z GUIDANCE. LOOKS LIKE THE SVR THREAT IS OVER FOR NOW...BUT COULD STILL SEE SOME ISOLD TS OVER THE SE PLAINS TONIGHT. STILL EXPECTING SOME DRY AIR TO PUSH INTO SE CO TOMORROW...BUT THERE WILL BE SCT SHOWERS AROUND IN THE MORNING. MAIN AREA TO WATCH THROUGH TOMORROW WILL BE THE UPPER ARKANSAS AND GUNNISON VALLEY...WHERE SOME GUIDANCE IS SHOWING A PERSISTENT SNOW BAND DEVELOPING. ROSE UPDATE ISSUED AT 543 PM MDT THU APR 16 2015 UPDATED THE FORECAST TO INCLUDE TELLER COUNTY AND NORTHERN FREMONT COUNTY IN A WINTER STORM WARNING. MULTIPLE BANDS OF PRECIP EXPECTED TO ROTATE IN FROM THE SE TONIGHT...WITH VARIOUS MODELS SHOWING .7 TO 1.4 INCHES OF QPF. WITH COOLING TEMPS AFTER SUNSET EXPECT ROADS TO ICE OVER...LEADING TO HAZARDOUS TRAVEL IN THE WARNED AREAS. ROSE UPDATE ISSUED AT 423 PM MDT THU APR 16 2015 UPDATED THE FORECAST TO CANCEL THE RED FLAG FOR THE SAN LUIS VALLEY. SCATTERED SHOWERS ARE OVER THE VALLEY AND HUMIDITY IS NO LONGER CRITICAL. ROSE && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 356 PM MDT THU APR 16 2015 ...MODERATE TO HEAVY SNOW POSSIBLE FOR THE MOUNTAINS TONIGHT AND FRIDAY... ...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE FOR THE FAR SOUTHEAST PLAINS AGAIN ON FRIDAY THOUGH THIS IS DEPENDENT ON HOW MUCH RAIN FALLS OVER THESE AREAS TONIGHT... ...MARGINAL POTENTIAL FOR SEVERE POSSIBLE FOR NORTHERN EL PASO AND KIOWA COUNTIES ON FRIDAY... STILL A HIGHLY DYNAMIC FORECAST AS MODELS HONE IN ON TRACK AND STRENGTH OF THE CLOSED LOW CURRENTLY ACROSS THE 4 CORNERS REGION. MODELS BOBBLE THE UPPER LOW SOUTHWARD A BIT THIS EVENING...THEN BACK TO THE NORTHEAST ACROSS THE CO/NM BORDER TONIGHT AS ENERGY ROTATES AROUND THE BASE OF THE UPPER LOW AND ACROSS CO. THEN IT MAKES STEADIER PROGRESS TO THE NORTHEAST INTO EAST CENTRAL CO ON FRIDAY. ALREADY SEEING ENHANCEMENT ACROSS THE SOUTHEAST MTS AND NRN NM AS THE NEXT IMPULSE APPROACHES. HRRR SEEMS TO HAVE PICKED UP ON THIS TREND FAIRLY WELL. WE SHOULD CONTINUE TO SEE SHOWERS FILL IN ACROSS THE SOUTHEAST MOUNTAINS...AND I-25 CORRIDOR...WITH SNOW LEVELS AROUND 6000-6500 FEET. SNOW LEVELS MAY ACTUALLY RISE A BIT FOR THE LOWER EASTERN SLOPES AS STRONG WAA OCCURS OVERNIGHT...WHICH COULD CAUSE A SWITCH BACK TO RAIN AT KCOS OVERNIGHT. HOWEVER...MTN AREAS SHOULD CONTINUE TO SEE SNOW AND HAVE EXPANDED ADVISORIES ACROSS MUCH OF THE MOUNTAIN AREAS. GIVEN THE CONVECTIVE POTENTIAL WITH THIS EVENINGS ROUND...CONCERNED THAT PORTIONS OF TELLER COUNTY COULD HIT WARNING CRITERIA...THOUGH DON`T THINK IT WILL BE WIDESPREAD ENOUGH ACROSS THE ZONE TO WARRANT AN UPGRADE. CENTRAL LAKE COUNTY COULD BE IN A SIMILAR BOAT...SO THESE AREAS WILL BE THE ONES TO WATCH CLOSELY. MEANWHILE...MODELS SHOW DEFORMATION BAND SNOW SPREADING WESTWARD INTO THE SOUTHWEST MOUNTAINS TONIGHT AND CONTINUING THROUGH FRIDAY. HAVE OPTED TO EXPAND ADVISORIES INTO THE LA GARITAS WHERE SNOW AMOUNTS ARE APPROACHING THE 6-12 INCH RANGE. STILL SOME QUESTION OVER THE EASTERN SAN JUANS THOUGH...COULD SEE A COUPLE INCHES FALL THERE TONIGHT...WITH ANOTHER 1-3 INCHES FALLING ON FRIDAY AS THE UPPER LOW WRAPS DEFORMATION BAND BACK TO THE SOUTHWEST ACROSS THE REGION. CONTEMPLATED AN ADVISORY FOR THIS REGION...BUT AM COMING UP SHY OF THE 6-12 INCHES NEEDED FOR A WINTER WX ADVISORY...THOUGH CERTAINLY SUBTLE CHANGES IN THE TRACK AND STRENGTH OF THE LOW COULD RESULT IN HEAVIER AMOUNTS FOR THIS REGION. STICKING TRUE TO THE GRIDS FOR NOW AND WILL LET LATER SHIFTS REASSESS. AS FOR SEVERE THUNDERSTORM POTENTIAL ACROSS THE PLAINS...APPEARS TIMING OF THE INITIAL WAVE THIS AFTERNOON WAS TOO QUICK FOR THE LOW LEVEL MOISTURE RETURN...AND NICE LINE OF THUNDERSTORMS HAS ALREADY DEVELOPED AND PUSHED EASTWARD INTO KANSAS. HOWEVER AS SURFACE WINDS HAVE VEERED MORE EASTERLY DUE TO FALLING SFC PRESSURES ACROSS NEW MEXICO...40S AND LOWER 50 DEW POINTS HAVE PULLED WESTWARD INTO THE FAR SOUTHEAST PLAINS. ACTIVITY INCREASING ACROSS NORTHERN NEW MEXICO MAY STILL HAVE A CHANCE TO INTERACT WITH THIS MOISTURE TO PRODUCE SOME ISOLATED SEVERE THUNDERSTORMS...WITH HAIL AND GUSTY WINDS THE PRIMARY STORM THREATS. OVERNIGHT...LATEST HRRR HINTS AT ANOTHER ROUND CLIPPING BY BACA COUNTY DURING THE 8Z TO 09Z TIMEFRAME...AND EVEN SOME SPOTTY THUNDERSTORMS POSSIBLE AS FAR WEST AS THE I-25 CORRIDOR. SO THOUGH MAIN THREAT FOR SEVERE THUNDERSTORMS WILL BE THIS EVENING...CAN`T RULE OUT A LOW GRADE SEVERE THREAT ACROSS THE FAR SOUTHEAST PLAINS EVEN DURING THE OVERNIGHT HOURS...THOUGH THUNDERSTORMS WILL TEND TO BE MORE ELEVATED. TOMORROW AS THE SURFACE LOW LIFTS INTO SOUTHEAST CO...COULD SEE SOME ISOLATED THUNDERSTORMS EVEN IN THE MORNING...AND LAPSE RATES WILL BE STEEP GIVEN THE MID LEVEL COOLING ASSOCIATED WITH THE SURFACE LOW. NAM12 SHOWS UP TO 1000 J/KG OF CAPE ACROSS NORTHERN PORTIONS OF THE SE PLAINS DURING THE MORNING...SO COULD HAVE ANOTHER CHANCE FOR SEVERE THUNDERSTORMS ON FRIDAY. BY AFTERNOON...DRY AIR SPREADS INTO THE SOUTHEAST PLAINS AS SURFACE LOW LIFTS NORTHWARD. THIS PUTS THE AXIS OF BEST INSTABILITY ALONG THE NORTHERN FRINGES OF THE SOUTHEAST PLAINS BY AFTERNOON...PRIMARILY NORTHEAST EL PASO AND KIOWA COUNTIES. THESE AREAS ARE OUTLOOKED FOR A MARGINAL SEVERE THREAT TOMORROW...AND THIS LOOKS ON TARGET. COULD SEE THIS MARGINAL THREAT SLIPPING SOUTHWARD A BIT TO ACCOUNT FOR ANY STRONG MORNING CONVECTION. BUT AS DRY AIR EXPANDS NORTHWARD...SO DOES THE POTENTIAL FOR CRITICAL FIRE WEATHER PARAMETERS...ESPECIALLY ACROSS LAS ANIMAS...BACA...BENT...PROWERS... AND OTERO COUNTIES. THE MITIGATING FACTOR WILL BE THE POTENTIAL FOR RAINFALL TO WET FUELS TONIGHT OVER THESE SAME ZONES. GIVEN THIS POTENTIAL...HAVE NOT GONE OUT WITH A FIRE WEATHER WATCH...BUT IF PRECIPITATION DOESN`T MATERIALIZE ACROSS A WIDESPREAD ENOUGH AREA ACROSS THESE REGION...THEN LATER SHIFTS MAY NEED TO HOIST A RED FLAG WARNING. -KT .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 356 PM MDT THU APR 16 2015 FRIDAY NIGHT THROUGH SATURDAY...MODELS HAVE SHIFTED A BIT OVER THE PST 24 HRS...BUT STILL REMAIN FAIRLY CONSISTENT WITH THE PLACEMENT AND PATH OF THE UPPER LOW. FRIDAY NIGHT THE LOW PRESSURE SYSTEM IS FORECAST TO BE CENTERED RIGHT OVER COLORADO...THEN OVER THE NEXT 24 HRS IT WILL WOBBLE A BIT BEFORE SLOWLY EXITING THE STATE VIA THE EASTERN BORDER. THIS PATTERN WOULD IMPLY THAT THE MTS...ESPECIALLY THE CONTDVD...WILL GET THE BRUNT OF SNOWFALL...MAINLY THROUGH FRIDAY NIGHT. THEREFORE...ONGOING WINTER HIGHLIGHTS RUNNING THROUGH 12Z SATURDAY LOOK REASONABLE. SNOW AMOUNTS WILL THEN TAPER OVER OVER THE DAY SATURDAY AS TEMPS BEGIN TO WARM AND THE SYSTEM WEAKENS. ISOLATED TO SCATTERED SHOWERS ARE FORECAST FOR THE REMAINDER OF THE LOWER ELEVATIONS...AND TEMPS DO NOT LOOK PARTICULARLY COLD WITH MIN TEMPS IN THE 30S TO AROUND 40 F FOR THE PLAINS...AND MAX TEMPS SATURDAY IN THE MID 50S TO LOWER 60S. SUNDAY AND MONDAY...THE UPPER SYSTEM WEAKENS AND EXITS TO THE EAST LATE SATURDAY...WITH BRISK NW FLOW ALOFT THEN SETTLING IN ACROSS THE STATE. A COUPLE OF UPPER SHORTWAVES ARE EXPECTED TO DROP DOWN ACROSS THE STATE ON BOTH DAYS...KEEPING THE THREAT OF SHOWER ACTIVITY FOR THE CWA IN PLACE. LOOK FOR SCATTERED SHOWERS OVER THE HIGHER TERRAIN...AND ISOLATED SHOWERS FOR THE PLAINS...WITH MAX TEMPS BOTH DAYS HOVERING IN THE 50S TO NEAR 60 F. TUESDAY THROUGH THURSDAY...CONFIDENCE IS FAIRLY LOW FOR WHAT HAPPENS BEYOND MONDAY...THOUGH LONG RANGE MODELS SEEM TO AGREE ON THE QUESTION MARK. A TEMPORARY RIDGE BUILDS INTO THE DESERT SW STARTING TUE...HELPING TO LOWERING PCPN CHANCES AS WELL AS BOOSTING MAX TEMPS FOR THE PLAINS BACK INTO THE 70S. TWO SEPARATE UPPER CLOSED LOW SYSTEMS APPROACH STARTING WED NIGHT...ONE OVER THE PAC NW AND THE OTHER OVER S CA...BUT THIS PATTERN WILL MOST LIKELY GO THROUGH MULTIPLE ADJUSTMENTS BEFORE THEN. MOORE && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1128 PM MDT THU APR 16 2015 LARGE UPPER LOW SPINNING NEAR THE 4 CORNERS REGION WILL PRODUCE WIDESPREAD MVFR/IFR AND LOCAL LIFR CONDITIONS ACROSS THE FLIGHT AREA THROUGH THROUGH TONIGHT AND UP THROUGH ABOUT 18Z FRIDAY. AFTER 18Z...IT LOOKS LIKE THE FOCUS FOR THESE CONDITIONS WILL SHIFT MAINLY TO THE WESTERN MOUNTAINS...WITH CONDITIONS ELSEWHERE IMPROVING TO VFR...WITH JUST ISOLATED TO SCATTERED MVFR/IFR. THE KCOS...KPUB AND KALS TAF SITES SHOULD ALL FOLLOW THIS TREND...WITH IMPROVEMENT EXPECTED AFTER 18Z FRIDAY. && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ059-062- 063-074-075. WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ077>079-084. WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058-060-061- 072-073-080-082. WINTER STORM WARNING UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR COZ076- 081. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR COZ066. && $$ UPDATE...ROSE SHORT TERM...KT LONG TERM...MOORE AVIATION...LW
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
445 AM EDT FRI APR 17 2015 .SYNOPSIS... 08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN UPPER LEVEL PATTERN THAT HAS CHANGED LITTLE OVER THE PAST 24 HOURS. NORTHERN STREAM WESTERLIES REMAIN MOSTLY ZONAL TO THE NORTH OF THE CANADIAN BORDER...WHILE MOIST SOUTHERN STREAM WESTERLIES CROSS OVER NORTHERN MEXICO FROM THE CENTRAL PACIFIC...AND THEN MOVE ALONG THE NORTHERN GULF COAST/SOUTHEAST CONUS. BETWEEN THESE TWO BELTS OF WESTERLIES...A LARGE CUTOFF LOW CENTERED OVER THE FOUR CORNERS REGION CONTINUES TO SPIN AND EJECT PIECES OF ENERGY OUT INTO THE SOUTHERN/CENTRAL PLAINS. A SERIES OF UPPER LEVEL IMPULSE ARE ALSO RIDING THE SOUTHERN STREAM FLOW AND FORCING PERIODIC FLARES OF CONVECTION OVER THE NORTH-CENTRAL GULF. THESE CONVECTIVE BURST WILL MAKE OUR LOCAL FORECAST A BIT TRICKY INTO SATURDAY AS WILL BE EXPLAINED IN THE SHORT TERM DISCUSSION BELOW. AT THE SURFACE...A COMPLEX PRESSURE PATTERN EXISTS JUST TO OUR NORTH AND NORTHEAST WITH A WEDGE HIGH IN PLACE ACROSS THE SOUTHEAST CONUS AND AN AREA OF LOW PRESSURE ANALYZED JUST OFF THE GA/SC COAST. THE FLOW AROUND THESE FEATURES HAS KEPT A WEAK FRONTAL BOUNDARY IN PLACE ACROSS NORTH-CENTRAL FLORIDA...BISECTING OUR FORECAST AREA FROM EAST TO WEST. THERE ARE AREAS OF LOWER CLOUDS EARLY THIS MORNING ALONG AND TO THE NORTH OF THIS BOUNDARY THAT WILL BE OF SOME CONCERN TO THE AVIATION COMMUNITY...ALTHOUGH THESE CIGS SHOULD LIFT QUICKLY...WITHIN A FEW HOURS OF SUNRISE. REGIONAL RADARS SHOW THAT THE LAST OF THE THURSDAY RESIDUAL SHOWER ACTIVITY ASSOCIATED WITH THE WEAK FRONT AND SEA BREEZES HAS DISSIPATED...LEAVING MOST OF THE FL PENINSULA DRY. HOWEVER...OFF TO THE NORTHWEST ACROSS THE NE GULF AND FL PANHANDLE WE SEE A BLOSSOMING AREA OF RAIN/EMBEDDED STORMS EXPANDING EASTWARD TOWARD THE NORTHERN NATURE COAST ZONES. THIS AREA OF RAIN LOOKS INCREASINGLY LIKELY TO IMPACT OUR NORTHERN NATURE COAST ZONES THIS MORNING. && .SHORT TERM (TODAY THROUGH SATURDAY)... TODAY...FIRST THINGS FIRST. THE FORECAST CONCERN FOR THE MORNING HOURS IS THE LARGE AREA OF RAIN OVER THE FL PANHANDLE/NORTHEAST GULF OF MEXICO. THIS CONVECTION CAN BE ATTRIBUTED TO THE SYNOPTIC LIFT ASSOCIATED WITH A SUBTLE SHORTWAVE PASSING OVER THE NORTH-CENTRAL GULF COAST...AND THE LOWER LEVEL RESPONSE OF A STRENGTHENING JET RESULTING IN A BROAD WAA/LIFT REGIME. THE MOST EFFICIENT LIFT WITH THE SHORTWAVE LOOKS TO PASS OFF TO OUR NORTH...HOWEVER...IT IS BECOMING MORE AND MORE EVIDENT THAT AT LEAST SOME OF THIS ACTIVITY WILL REACH OUR NORTHERN NATURE COAST ZONES...MAINLY LEVY/CITRUS/NORTHERN SUMTER. THE RAP AND HRRR FOR SEVERAL RUNS NOW HAVE BEEN AGGRESSIVE IN BRINGING THIS MOISTURE EASTWARD INTO THESE AREA AFTER 11-12Z. IT IS HARD TO ARGUE WITH THIS SOLUTION GIVEN THE CURRENT RADAR TRENDS. HAVE BUMPED UP RAIN CHANCES TO LIKELY OVER OUR FAR NORTHERN ZONES THIS MORNING TO ACCOUNT FOR THIS. NOW...THE ARRIVAL OF THIS RAINFALL...WHICH IS NOT HANDLED WELL BY MANY OF THE 00Z GUIDANCE MEMBERS...MAKES THE FORECAST TRICKY FOR THE AFTERNOON HOURS FURTHER SOUTH INTO THE I-4 CORRIDOR AND PERHAPS FURTHER SOUTH. THERE ARE TWO POSSIBILITIES. ONE IS THAT THE SHOWER ACTIVITY SLOWS THE DIURNAL HEATING ACROSS THE NATURE COAST AND ACTUALLY ENDS UP FORCING WEAK FRONTOGENESIS ALONG THE BOUNDARY DUE TO DIFFERENTIAL DIURNAL HEATING. IN THIS CASE THE SHOWERS/STORMS ACTIVITY INTO THE CENTRAL FORECAST AREA COULD BE ENHANCED (EVEN BACK TOWARD THE COAST). THE LATEST 07Z HRRR SOLUTION IS SHOWING SOMETHING SIMILAR TO THIS. THE SECOND POSSIBILITY IS THAT THE RAINFALL COOLING AND MOMENTUM ARE ENOUGH TO PUSH AN OUTFLOW BOUNDARY SOUTH THROUGH THE CENTRAL PENINSULA AND ACT TO INHIBIT ADDITIONAL CONVECTIVE DEVELOPMENT THIS AFTERNOON IN ITS WAKE. METEOROLOGY IS NEVER AN EXACT SCIENCE...AND THIS IS A TRICKY FORECAST TO SAY THE LEAST. IT IS LIKELY BEST IN THIS SCENARIO NOT TO GET TOO HUNG UP ON DETAILS...SINCE THIS JUST IS NOT A PATTERN WHERE THAT IS REALISTIC. SO...WILL GO WITH LIKELY RAIN CHANCES FAR NORTH THIS MORNING...WITH THE ENERGY AND HIGHEST RAIN CHANCES THEN PASSING OUT OF THESE AREA FOR THE AFTERNOON. FURTHER SOUTH...WILL EXPECT SOME ENHANCEMENT ALONG THE BOUNDARY FROM THE NORTH AND SOME SEA-BREEZE INTERACTION FURTHER SOUTH. IT APPEARS AS THROUGH THE SOUTHERN HALF OF THE AREA WILL HAVE THE BEST CHANCES AT A DEFINED SEA-BREEZE LATER TODAY. SO SOUTH OF THE I-4 CORRIDOR...THE BEST RAIN CHANCES WILL BE LATE AFTERNOON AND EVENING HOURS...AND GENERALLY INLAND AWAY FROM THE COAST. TONIGHT...SITUATION REMAIN TRICKY. THE QUESTION IS DO WE BELIEVE THE PARAMETERIZED GUIDANCE OR THE CONVECTION ALLOWING GUIDANCE? THE PARAMETERIZED GUIDANCE WOULD SUGGEST EVENING STORMS SETTLE DOWN AND MOST OF THE OVERNIGHT IS BENIGN IN TERMS OF SENSIBLE WEATHER. MANY OF THE HIRES CONVECTION ALLOWING MEMBERS SHOW A ROUND OF STORMS QUICKLY CROSSING THE NE GULF AND INTO THE NATURE COAST (EVEN AS FAR SOUTH AS THE TAMPA BAY AREA). THESE STORMS DEVELOP ALONG THE FOCUS OF A LARGE OUTFLOW SURGE INITIATED OFF THE LOUISIANA COAST TODAY. IT IS SURPRISING HOW MANY MEMBERS ARE SHOWING A SIMILAR SCENARIO. HOWEVER...SO MANY THINGS HAVE TO COME TOGETHER FOR THIS CONVECTIVE BLOB TO EVEN EXIST...INCLUDING THE PROPER PLACEMENT AND TIMING OF THE CONVECTION OF THE LOUISIANA COAST. TOO MANY UNCERTAINTIES HERE...AND HIRES GUIDANCE IS OFTEN OVER AGGRESSIVE IN THESE TYPE OF CASES. WILL ALLOW FOR LOW END POPS OVER THE NATURE COAST TONIGHT...BUT LEAN MORE TOWARD THE BENIGN GFS/NAM/ECMWF SOLUTIONS UNTIL WE SEE EVIDENCE TO GO AGAINST THESE RELIABLE SOURCES. SATURDAY...WELCOME TO THE WEEKEND. HEIGHT FALLS OVER THE SOUTHERN PLAINS ASSOCIATED WITH THE EASTWARD EJECTING CUTOFF LOW WILL ACTUALLY HELP TO RIDGE UP THE UPPER FLOW OVER OUR AREA. SO WHILE PLENTY OF SHOWER/STORM ACTIVITY WILL BE ONGOING ACROSS THE NORTH- CENTRAL GULF...THIS ORGANIZED CONVECTION WILL NOT BE ABLE TO COME EASTWARD JUST YET. ALSO...OUR SURFACE BOUNDARY LOOKS TO BE JUST ABOUT GONE BY THIS TIME...WITH A VERY WEAK GRADIENT LEFT BEHIND. THE WEAK GRADIENT MEANS OUR FLOW WILL BE DOMINATED BY THE DEVELOPING AFTERNOON SEA-BREEZES. JUST ABOVE THE SURFACE THE PREVAILING FLOW WILL BE FRONT THE WEST...SO THE WEST COAST SEA BREEZE SHOULD QUICKLY TRANSLATE INLAND AFTER INITIATION. WITH THIS IN MIND...WILL KEEP THE BEST CHANCE OF DIURNAL STORMS SATURDAY AFTERNOON/EVENING GENERALLY WELL INLAND...WITH ONLY LOW RAIN CHANCES BACK TOWARD THE COAST. EVEN THESE LOW POPS SHOULD END BY MID/LATE AFTERNOON IN THE WAKE OF THE SEA BREEZE PASSAGE. && .LONG TERM (SUNDAY THROUGH NEXT THURSDAY)... THE WEEKEND FINISHES WITH AN UPPER TROUGH OVER THE NORTH AND CENTRAL HIGH PLAINS WHILE A RIDGE REACHES FROM THE EAST GULF TO THE UPPER GREAT LAKES. A SURFACE LOW IN THE CENTRAL PLAINS HAS A COLD FRONT THAT ARCS DOWN THROUGH THE MISSISSIPPI VALLEY AND INTO THE GULF. HIGH PRESSURE IN EASTERN CANADA RIDGES SOUTH TO FL...BRIDGING A WARM FRONT LIKE BOUNDARY OVER GA AND NW FL COASTAL WATERS. THROUGH TUE - THE UPPER TROUGH AND SURFACE LOW LIFT UP OUT OF THE PLAINS AND ACROSS THE GREAT LAKES INTO CANADA...WITH THE COLD FRONT PUSHING EAST AND OFF THE EASTERN SEABOARD AND SETTLING SOUTHWARD OVER FL. THE UPPER RIDGE AND CANADIAN HIGH PRESSURE...ALONG WITH THE WARM FRONT OFF THE SE U.S COAST...SHIFT OUT OVER THE OPEN ATLANTIC. FOR WED AND THU - THE UPPER TROUGH SLOWS AS IT CONTINUES TO LIFT ACROSS EASTERN CANADA WITH ZONAL FLOW SETTING UP OVER THE GULF REGION. SURFACE HIGH PRESSURE BUILDS IN OVER THE CENTRAL AND SOUTHERN PLAINS THEN TRACKS ACROSS THE LOWER EASTERN SEABOARD TO THE ATLANTIC. THE FRONT ACROSS FL HAS NOW STALLED ACROSS THE SOUTHERN HALF OF THE STATE AS IT WEAKENS. THE DEPARTING WARM FRONT AND APPROACHING COLD FRONT WILL PROVIDE AMPLE MOISTURE...MAXIMUM PWAT VALUES ALONG THE TWO BOUNDARIES ARE IN THE 1.8 TO 2.0 RANGE...FOR SHOWERS IN THE SLIGHT CHANCE TO LIKELY CATEGORY ALONG WITH SOME THUNDERSTORMS. THE COLD FRONT MOVING IN ALONG WITH THE UPPER TROUGH...BEFORE IT LIFTS AWAY...WILL RESULT IN THE HIGHEST HIGHEST COVERAGE SUN AND MON. AS THE FRONT MOVES SOUTH AND WEAKENS THROUGH MID-WEEK THE RAIN CHANCES BEGIN TO TREND DOWN FROM NORTH TO SOUTH. TEMPERATURES WILL RUN A FEW DEGREES ABOVE NORMAL ALTHOUGH THEY WILL COOL SLIGHTLY THROUGH THE PERIOD...THANKS TO CLOUD COVER AND RAINFALL. && .AVIATION... AREA OF IFR/MVFR CIGS EARLY THIS MORNING FROM KTPA TO KLAL AND NORTHWARD. FURTHER SOUTH VFR CONDITIONS PREVAIL. THESE CIG RESTRICTIONS ARE ALONG AND NORTH OF A STATIONARY FRONTAL BOUNDARY. SO...EXPECT RESTRICTIONS TO CONTINUE FOR SEVERAL MORE HOURS AND THEN LIFT WITHIN A FEW HOURS AFTER SUNRISE. GENERAL VFR CONDITIONS WILL THEN PREVAIL THROUGH THE MAJORITY OF THE DAY AND EVENING HOURS. SCT THUNDERSTORMS ARE EXPECTED BY MID AFTERNOON...BUT GENERALLY SPEAKING THE HIGHEST COVERAGE WILL BE INLAND FROM TERMINALS. && .MARINE... WIND AND SEAS REMAIN LOW THROUGH SATURDAY AWAY FROM ANY THUNDERSTORMS. A WEAK FRONTAL BOUNDARY REMAINS IN PLACE ACROSS THE NORTHEAST GULF TODAY. WINDS WILL SHIFT ONSHORE THIS AFTERNOON TO THE SOUTH OF THIS BOUNDARY...MAINLY SOUTH OF TARPON SPRINGS...AND THEN RETURN TO AN EAST/SOUTHEAST DIRECTION TONIGHT. SEA BREEZE DEVELOPMENT IS EXPECTED FOR ALL COASTAL AREAS SATURDAY AFTERNOON. && .FIRE WEATHER... RELATIVE HUMIDITY WILL REMAIN WELL ABOVE CRITICAL LEVELS THROUGH THE WEEKEND KEEPING RED FLAG CONDITIONS FROM BEING REACHED. SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST TODAY FOR MAINLY THE NATURE COAST ZONES AND INTERIOR CENTRAL AND SOUTH-CENTRAL ZONES. SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP ALONG THE SEA BREEZE SATURDAY AFTERNOON...WITH THE GREATEST CHANCE OF A WETTING RAIN WELL INLAND FROM THE COAST. FOG POTENTIAL... AREAS OF FOG EXPECTED AFTER MIDNIGHT TONIGHT AND AGAIN SATURDAY NIGHT. THE HIGHEST POTENTIAL FOR FOG WILL EXIST GENERALLY ALONG AND NORTH OF THE I-4 CORRIDOR. && .PRELIMINARY POINT TEMPS/POPS... TPA 85 71 85 73 / 30 30 30 10 FMY 88 71 88 72 / 10 10 30 20 GIF 87 70 86 71 / 60 50 50 50 SRQ 85 71 84 71 / 10 20 20 10 BKV 86 67 86 67 / 40 30 30 30 SPG 84 73 84 75 / 20 30 20 10 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ SYNOPSIS/SHORT TERM/MARINE/AVIATION/FIRE WX...MROCZKA LONG TERM/DECISION SUPPORT SERVICES...RUDE
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
433 AM EDT FRI APR 17 2015 .NEAR TERM [THROUGH TODAY]... EARLY THIS MORNING A LARGE AREA OF RAIN WAS SITUATED ALONG THE NORTH- CENTRAL GULF COAST, WITH LIGHT TO MODERATE RAIN JUST BEGINNING TO ENTER OUR WESTERN FORECAST AREA AT 07 UTC. THE LAST SEVERAL RUNS OF THE HRRR APPEAR TO HAVE THE BEST HANDLE ON THE INITIAL CONDITIONS, BUT STILL DIVERGE AFTER ABOUT 5-6 HOURS. THEREFORE, CONFIDENCE IS MUCH HIGHER FOR THE PRE-DAWN HOURS WITH LIGHT TO MODERATE RAIN EXPECTED TO CONTINUE TO SPREAD INTO OUR AREA; HIGHEST POPS WILL BE IN THE FLORIDA PANHANDLE WITH HEAVIER RAIN RATES FOCUSED TOWARD THE GULF COAST. AFTER SUNRISE THE FORECAST BECOMES MORE UNCERTAIN WITH MODELS INDICATING A VARIETY OF SOLUTIONS. ONE GENERAL TREND APPEARS TO BE THE PRIMARY AREA OF RAIN BEGINNING TO DISSIPATE LATER IN THE MORNING, FOLLOWED BY REDEVELOPMENT OF RAIN (MORE CONVECTIVE THIS TIME) IN OUR WESTERN FORECAST AREA OR JUST WEST OF OUR AREA BETWEEN 16 UTC AND 19 UTC. HOWEVER, PINPOINTING A SPECIFIC AREA WHERE RAIN IS MORE LIKELY OR RAINFALL TOTALS MAY BE HIGHER DURING THE DAYTIME IS TOUGHER DUE TO MODEL DIFFERENCES AND THE LACK OF A STRONG FORCING MECHANISM. THEREFORE, WE KEPT A "LIKELY" POP IN THE FORECAST EVERYWHERE WITH AN EMPHASIS ON STRATIFORM PRECIP IN THE MORNING (RAIN, MORE STABLE) AND A TREND TOWARD CONVECTIVE PRECIP IN THE AFTERNOON (SHOWERS AND STORMS, MORE UNSTABLE). HOWEVER, OUR GENERAL FEELING IS THAT RAIN AND STORMS WILL BECOME FOCUSED CLOSER TO THE GULF COAST WITH TIME - NEARER TO THE SURFACE FRONT. WITH VERY HIGH PRECIPITABLE WATER FOR APRIL AND WEAK FLOW BELOW 20,000 FT, ANY LOW TOPPED CONVECTION WOULD HAVE THE POTENTIAL TO PRODUCE SOME LOCALIZED HEAVY RAINFALL AND FLOODING. GIVEN THE EXPECTED ABUNDANCE OF RAIN AND CLOUD COVER TODAY, WE TRENDED TEMPERATURES TOWARD THE LOWER END OF GUIDANCE WITH HIGHS MAINLY IN THE LOW-MID 70S. .SHORT TERM [TONIGHT THROUGH SUNDAY]... THE UNUSUALLY WET PATTERN FOR APRIL WILL CONTINUE THROUGH THE WEEKEND. HOWEVER, A CHANGE IS ON THE WAY. THE UPPER LOW OVER THE CENTRAL PLAINS TONIGHT WILL LIFT TO THE NORTHEAST AND BECOME ABSORBED IN THE NORTHERN STREAM ON SUNDAY. THE AXIS OF THE BROAD UPPER TROUGH AND ASSOCIATED COLD FRONT WILL APPROACH LATE SUNDAY WITH A DRIER AIRMASS ARRIVING EARLY NEXT WEEK. UNTIL THEN, SHOWERS AND THUNDERSTORMS CAN BE EXPECTED EVEN DURING THE OVERNIGHT HOURS. THE BEST CHANCE WILL BE ON SUNDAY WITH LIKELY TO CATEGORICAL POPS. DESPITE THE EXTENSIVE CLOUD COVER AND RAIN CHANCES, TEMPS WILL CONTINUE TO BE ABOVE SEASONAL LEVELS. .LONG TERM [SUNDAY NIGHT THROUGH FRIDAY]... THE COLD FRONT WILL PUSH THROUGH LATE MONDAY INTO EARLY TUESDAY BUT SIGNIFICANT DRYING OF THE MID-UPPER LEVELS WILL HAVE ALREADY BEGUN ON MONDAY WITH POPS ONLY IN THE CHANCE CATEGORY. TEMPERATURES WILL NOT BE THAT COOL BEHIND THE FRONT, BUT THE LOWER HUMIDITY WILL MAKE IT FEEL MORE PLEASANT THAN WHAT WE HAVE EXPERIENCED THE PAST SEVERAL DAYS. ANOTHER COLD FRONT AND NEXT DECENT CHANCE FOR RAIN WILL ARRIVE BY THE END OF THE WORK WEEK. && .AVIATION... [THROUGH 06Z SATURDAY] IFR CIGS PREVAILED AT THE TERMINALS AT TAF ISSUANCE TIME, AND IFR-LIFR CIGS SHOULD LARGELY PREVAIL INTO THE MID MORNING HOURS AS RAIN BUILDS INTO THE AREA. RAIN WILL LIKELY OCCUR AT ALL OF THE TERMINALS AT SOME POINT TODAY, BUT TIMING IS SOMEWHAT UNCERTAIN. CIGS SHOULD IMPROVE SOMEWHAT IN THE AFTERNOON, PERHAPS INTO THE MVFR RANGE, BUT IFR-LIFR CIGS ARE LIKELY ONCE AGAIN TONIGHT. && .MARINE... LIGHT SOUTHERLY WINDS ARE EXPECTED TODAY AND SATURDAY. WINDS WILL INCREASE ON SUNDAY TO AT LEAST CAUTIONARY LEVELS AS A COLD FRONT APPROACHES. WINDS AND SEAS WILL DECREASE AS THEY BECOME OFFSHORE IN THE WAKE OF THE FRONT EARLY NEXT WEEK. && .FIRE WEATHER... RED FLAG CONDITIONS ARE NOT EXPECTED WITH HIGH RH PREVAILING THROUGH THE WEEKEND. WETTING RAINS ARE LIKELY AND FUEL MOISTURE LEVELS SHOULD STAY HIGH. && .HYDROLOGY... THOUGH NOT WIDESPREAD, RECENT HEAVY RAINS IN THE FL PANHANDLE, SOUTHEAST AL, AND SOUTHWEST GA HAVE RESULTED IN SOME SHARP RISES IN LOCAL RIVER STAGES. IN PARTICULAR, THE OCHLOCKONEE RIVER AT THOMASVILLE, APALACHICOLA RIVER AT BLOUNTSTOWN, AND CHOCTAWHATCHEE RIVER AT BRUCE ARE LIKELY TO BE ABOVE LOCAL ACTION STAGE FOR THE NEXT SEVERAL DAYS, BUT REMAIN BELOW FLOOD STAGE. OVER THE NEXT SEVERAL DAYS, WE EXPECT STORM TOTAL RAINFALL AMOUNTS TO RANGE FROM ABOUT AN INCH IN NORTH FL, TO 4 INCHES IN SOUTHEAST AL AND PORTIONS OF THE FL PANHANDLE. LOCALLY HIGHER AMOUNTS EXCEEDING 6 INCHES ARE POSSIBLE. FORTUNATELY MANY OF THE RIVER STAGES IN SOUTHEAST AL AND THE FL PANHANDLE WERE BELOW NORMAL BEFORE THIS WEEK. HOWEVER, THE RAINS FROM THIS WEEK HAVE BROUGHT MANY OF THESE RIVERS TO ABOVE- NORMAL FLOWS. DEPENDING ON WHERE THE HEAVIEST RAIN SETS UP OVER THE NEXT SEVERAL DAYS, MORE OF THESE RIVERS COULD REACH LOCAL ACTION STAGE NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 77 66 84 69 81 / 70 30 40 50 70 PANAMA CITY 75 68 79 71 77 / 70 30 60 60 70 DOTHAN 72 63 79 67 77 / 70 30 60 80 70 ALBANY 73 62 79 66 78 / 60 30 40 60 70 VALDOSTA 76 64 84 67 81 / 70 30 40 30 70 CROSS CITY 79 66 84 67 83 / 60 30 40 30 60 APALACHICOLA 77 70 80 72 79 / 70 30 50 60 70 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AL...NONE. GM...NONE. && $$ NEAR TERM...LAMERS SHORT TERM...BARRY LONG TERM...BARRY AVIATION...LAMERS MARINE...BARRY FIRE WEATHER...LAMERS HYDROLOGY...FOURNIER
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
215 AM EDT FRI APR 17 2015 .UPDATE... AREA OF RAIN CONTINUES TO BLOSSOM ACROSS THE CWFA THIS EVENING. LATEST RUNS OF THE HRRR SHOW THE RAINFALL SHOULD TAPER OFF AFTER 06Z. UPDATED THE POPS EARLIER THIS EVENING...AND JUST UPDATED THEM AGAIN TO CATEGORICAL OVER A GOOD PORTION OF THE CWFA. HAVE ALSO TWEAKED THE HOURLY TEMPS AND DEWPOINTS. CHANCES OF CONVECTION REMAIN SMALL...BUT SHOULD CONTINUE THROUGH MIDNIGHT. && .PREV DISCUSSION... /ISSUED 348 PM EDT THU APR 16 2015/ SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... A WET/UNSETTLED PATTERN LOOKS TO PERSIST THROUGH THE SHORT TERM. THE WEDGE PERSISTS THIS AFTERNOON AND SHOULD CONTINUE INTO THE OVERNIGHT WITH THE WEDGE GRADUALLY BREAKING DOWN FRIDAY. SHOWERS AND A FEW THUNDERSTORMS WERE INCREASING TO THE WEST AND SHOULD CONTINUE TO MOVE NORTHEAST...WITH HIGH RESOLUTION MODELS SHOWING WIDESPREAD RAINFALL FOR MUCH OF THE NIGHT. THIS SHOULD CONTINUE INTO FRIDAY MORNING. MOST UNSTABLE AIR WILL BE AROUND THE EDGE OF THE COOLER AIR AND HAVE INCLUDED THUNDER FOR TONIGHT ALONG THE NORTHERN AND WESTERN ZONES. SOME GENERAL INCREASE IN INSTABILITY FOR FRIDAY AND HAVE MENTIONED THUNDER ACROSS THE AREA. MODELS HINT AT A BREAK UNTIL NEXT WAVE APPROACHES THE FORECAST AREA ON SATURDAY...SO HAVE REDUCED THE POPS FOR FRIDAY NIGHT. FLOODING ISSUES MAY BE HIT AND MISS AND HAVE NOT ISSUED ANY FLOOD WATCH. SOME LOCAL RIVER AND STREET FLOODING WILL CONTINUE TO BE POSSIBLE. TEMPERATURES THIS AFTERNOON ARE RUNNING A BIT LOWER THAN FORECAST AND MAY HOLD NEAR STEADY OVERNIGHT WITH THE EASTERLY WINDS. SOME WARMING EXPECTED ON FRIDAY. 41 LONG TERM /SATURDAY THROUGH THURSDAY/... NO MAJOR CHANGES MADE TO THE EXTENDED FORECAST. MODELS STILL A BIT SLOWER WITH INCREASING DEEP MOISTURE ON SATURDAY WITH THE BEST MOISTURE NOT BEGINNING TO MOVE IN UNTIL 00Z SUN. BEST OPPORTUNITY FOR RAINFALL CONTINUES TO BE SUN/SUN NIGHT WITH HIGH SHOWERS CHANCES AND A CHANCE OF THUNDERSTORMS ACROSS THE AREA. PWS ACROSS THE AREA INCREASE INTO THE 1.5 TO 1.75 INCH RANGE BEGINNING 00Z SUN THROUGH 00Z MON. THIS WILL BRING PERIODS OF MODERATE TO HEAVY RAIN THIS WEEKEND ACROSS THE ENTIRE CWA. THE POTENTIAL FOR LOCALIZED FLOODING WILL NEED TO BE CLOSELY MONITORED. A COLD FRONT MOVES ACROSS THE AREA MONDAY/MONDAY NIGHT AND RAIN CHANCES WILL END MONDAY NIGHT. TUESDAY AND WEDNESDAY ARE EXPECTED TO BE DRY AS THE WESTERLY UPPER FLOW DRIES OUT. A SHORT WAVE IN THE UPPER FLOW THU MORNING WILL NEED TO BE WATCHED FOR POSSIBLE LIGHT PRECIP CHANCES. HAVE INTRODUCE A SLIGHT CHANCE OF PRECIP FOR NOW. TEMPERATURES ARE GENERALLY EXPECTED TO BE NEAR TO ABOVE NORMAL. 01 PREVIOUS LONG TERM DISCUSSION /FRIDAY NIGHT THROUGH WEDNESDAY/ /ISSUED AT 505 AM EDT THU APR 16 2015/...WE LOOK TO BE IN BETWEEN SYSTEMS FRIDAY NIGHT AS WEAK SURFACE HIGH PRESSURE AND A SHORT WAVE RIDGE ALOFT PREDOMINATE. THIS WILL TRANSLATE TO ONLY LOW POPS DURING THE EVENING FOR CENTRAL AND PARTS OF NORTH GEORGIA. FORECAST LOW TEMPERATURES RUNNING 8-10 DEGREES ABOVE NORMAL. MODELS NOW SLOWER WITH INCREASING DEEP MOISTURE ON SATURDAY IN THE SW UPPER FLOW AND INCREASING SOUTHERLY LOW LEVEL FLOW. BEST RAIN CHANCES NOW LOOK TO BE LATE SATURDAY AND LIGHT. DEEPEST MOISTURE INCREASES SATURDAY NIGHT AND CONTINUES INTO SUNDAY NIGHT WITH HIGH SHOWERS CHANCES AND A CHANCE OF THUNDERSTORMS ACROSS THE AREA. A COLD FRONT MOVES ACROSS THE AREA MONDAY/MONDAY NIGHT AND RAIN CHANCES WILL END MONDAY NIGHT. TUESDAY AND WEDNESDAY ARE EXPECTED TO BE DRY AS THE WESTERLY UPPER FLOW DRIES OUT. A SHORT WAVE IN THE UPPER FLOW LATE WEDNESDAY WILL NEED TO BE WATCHED FOR POSSIBLE LIGHT PRECIP CHANCES. UPDATED... AT THIS TIME...A PERIOD OF MODERATE TO HEAVY RAIN WILL BE POSSIBLE THIS WEEKEND...MOST SO FOR NORTHEAST GEORGIA. THE POTENTIAL FOR LOCALIZED FLOODING WILL NEED TO BE CLOSELY MONITORED. TEMPERATURES ARE GENERALLY EXPECTED TO BE NEAR TO ABOVE NORMAL. BDL && .AVIATION... 06Z UPDATE... IFR OR LOWER CONDITIONS ARE EXPECTED TO PREDOMINATE ACROSS THE AREA THROUGH 14Z...WITH CONDITIONS IMPROVING TO MVFR BY 16Z-18Z MOST AREAS. MAY SEE SOME BRIEF...SCATTERED PERIODS OF VFR CONDITIONS BETWEEN 20Z AND 02Z. SOME LIGHT RAIN OR SHOWERS ARE POSSIBLE THROUGH 16Z...WITH MAINLY SHOWERS SCATTERED ACROSS THE AREA...AND A FEW ISOLATED THUNDERSTORMS...16Z-02Z. EAST WINDS 4-8KT THROUGH 16Z WITH WINDS BECOMING SOMEWHAT VARIABLE IN DIRECTION 16Z-20Z. WINDS ARE EXPECTED TO BE GENERALLY WESTERLY AFTER 20Z...BUT WILL BE LIGHT AT 5KTS OR LESS. //ATL CONFIDENCE...06Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. 20 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 54 72 58 81 / 90 40 20 40 ATLANTA 53 73 61 77 / 100 50 20 50 BLAIRSVILLE 52 71 54 75 / 100 40 20 40 CARTERSVILLE 53 73 57 79 / 100 50 20 50 COLUMBUS 57 73 61 79 / 100 60 20 50 GAINESVILLE 53 71 58 77 / 100 40 20 40 MACON 57 72 58 79 / 100 60 20 40 ROME 54 73 57 78 / 60 40 20 50 PEACHTREE CITY 53 73 57 77 / 100 50 20 50 VIDALIA 58 73 62 82 / 80 50 30 20 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
331 AM CDT FRI APR 17 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 331 AM CDT FRI APR 17 2015 A DENSE FOG ADVISORY ISSUED AROUND 2 AM FOR EASTERN IL WILL BE ALLOWED TO CONTINUE THROUGH 9 AM CDT. THE PAST HOUR OR TWO THE DENSE FOG WITH VSBYS 1/4 MILE OR LESS HAS BEEN CONFINED TO AREAS EAST OF I- 57 AND COULD EXPAND FURTHER WEST OF I-57 WITH AREAS OF FOG AND PATCHY DENSE FOG AS FAR WEST AS I-55 PER HRRR MODEL UNTIL 9 AM. ONCE THE FOG LIFTS LATER THIS MORNING A NICE MILD SPRING DAY IS SHAPING UP ACROSS CENTRAL AND SOUTHEAST IL WITH WEAK HIGH PRESSURE OVER IN AND SOME UPPER LEVEL RIDGING INTO IL GIVING MOSTLY SUNNY SKIES AND LIGHT WINDS AND MILD HIGHS IN THE MID TO UPPER 70S. && .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 331 AM CDT FRI APR 17 2015 DRY CONDITIONS STILL EXPECTED TO CONTINUE ACROSS CENTRAL AND SOUTHEAST IL THROUGH AT LEAST SAT MORNING WITH JUST ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE DURING MID/LATE SAT AFTERNOON ALONG AND SW OF A GALESBURG TO LINCOLN TO LAWRENCEVILLE LINE. UPPER LEVEL RIDGE INTO THE OHIO RIVER VALLEY AND IL YET ON SATURDAY TO BRING A NOTHER MILD SPRING DAY IN THE MID TO UPPER 70S SATURDAY, WITH MILDEST READINGS NEAR THE IN BORDER WHERE MORE SUNSHINE EXPECTED. LARGE CUTOFF UPPER LEVEL LOW OVER COLORADO TONIGHT AND SATURDAY GETS ABSORBED BY NORTHERN STREAM CUTOFF LOW NORTH OF ND/MN SUNDAY AND MONDAY. WARM AIR ADVECTION SHOWERS AND SCATTERED THUNDERSTORMS TO SPREAD NE ACROSS CENTRAL AND SOUTHEAST IL DURING SATURDAY NIGHT ESPECIALLY AFTER MIDNIGHT AND CONTINUE SUNDAY. FAIRLY STRONG SURFACE LOW PRESSURE EJECTS NE FROM OK PANHANDLE TO NEAR CENTRAL IL BY SUNSET SUNDAY AND SWEEPS A COLD FRONT EAST THROUGH IL SUNDAY NIGHT. THIS TO LIKELY BRING MORE SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT AND SPC HAS MARGINAL RISK OF SEVERE STORMS SW OF I-74 SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING WITH SLIGHT RISK SW OF A PITTSFIELD TO EFFINGHAM TO LAWRENCEVILLE LINE FOR LARGE HAIL AND DAMAGING WIND GUSTS POSSIBLE. HIGHS SUNDAY MOSTLY IN THE LOWER 70S WITH SOME UPPER 60S NORTH OF I-74. A LARGE UPPER LEVEL TROF THEN DOMINATES THE MIDWEST MONDAY-THURSDAY AS STRONG CUTOFF LOW MOVES SLOWLY EAST ACROSS THE NORTHERN GREAT LAKES REGION. SHOWERS SHOULD DIMINISH TO WIDELY SCATTERED SHOWERS OVER CENTRAL IL ON MONDAY WITH BEST CHANCES OF SHOWERS OVER IN AND NORTHERN IL. COOLER HIGHS OF 60-65F MONDAY WITH MILDEST READINGS BY LAWRENCEVILLE. HAVE DRY AND COOL CONDITIONS MONDAY NIGHT THROUGH TUE NIGHT. THEN SMALL CHANCES OF SHOWERS WED/THU WITH A WEATHER SYSTEM APPROACHING FROM THE SW WITH GFS MODEL TRENDING MUCH WETTER DURING THIS TIME FRAME WHILE ECMWF MODEL IS KEEPING IL DRY. COOL HIGHS IN THE UPPER 50S/LOWER 60S TUE-WED WITH LOWS IN THE UPPER 30S TO MID 40S, WITH COOLEST READINGS FROM I-74 NORTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1157 PM CDT THU APR 16 2015 AREAS MVFR CONDITIONS WITH LOCAL IFR IN FOG FROM AROUND KCMI-K1H2 EASTWARD THIS EVENING...WITH VFR TO THE WEST AS A SURFACE HIGH PRESSURE CENTER REMAINS NEAR THE NORTHEAST CORNER OF THE STATE. FOG WILL SPREAD WESTWARD TO AROUND KBMI-KSPI EASTWARD WHERE GREATEST AMOUNTS OF LOW LEVEL MOISTURE REMAIN ALONG WITH LIGHT WINDS AND LACK OF HIGHER LEVEL CLOUD COVER. WITH DAYTIME HEATING...FOG SHOULD DISSIPATE 13Z-15Z WITH SCATTERED CUMULUS DEVELOPMENT ABOVE MVFR THRESHOLDS. LIGHT SSE WINDS 5-8 KTS DEVELOPING IN THE DAYTIME PERIOD...CONTINUING INTO EVENING. && .ILX WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR ILZ044>046- 054>057-061>063-066>068-071>073. && $$ SHORT TERM...07 LONG TERM...07 AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1157 PM CDT THU APR 16 2015 .UPDATE... ISSUED AT 901 PM CDT THU APR 16 2015 HIGH PRESSURE OVER THE REGION WILL RESULT IN MINIMAL CLOUD COVER OVERNIGHT. HOWEVER...FAIRLY HIGH DEWPOINTS MAINLY IN THE 50S WILL LIKELY PRODUCE AREAS OF FOG AS THE CLEAR SKIES ALLOW GOOD RADIATIONAL COOLING ALONG WITH LIGHT WINDS ASSOCIATED WITH THE HIGH. ALREADY HAVE AREAS OF FOG IN FORECAST FROM I-57 CORRIDOR EASTWARD...WHICH IS IN GOOD AGREEMENT WITH THE LATEST HRRR MODEL. MAIN UPDATE POSSIBILITY WOULD BE EXTENT OF FOG WESTWARD...AS WELL AS IF ANY DENSE AREAS DEVELOP. FOR NOW...CURRENT FORECAST LOOKS IN GOOD SHAPE WITH ONLY UPDATES FOR MINOR TEMPERATURE/CLOUD TRENDS SO FAR. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 310 PM CDT THU APR 16 2015 HIGH PRESSURE RIDGE SLIDING OFF TO THE EAST AS QUASI ZONAL FLOW TRANSITIONING TO A SLIGHTLY SOUTHWESTERLY FLOW WITH A DEEP LOW DIGGING IN AT H5 OVER THE DESERT SW. REMNANT MOISTURE AFFILIATED WITH WAVE PULLING OFF TO THE EAST STILL IMPACTING THE EASTERN EDGES OF THE STATE THIS AFTERNOON WITH A MORE PERSISTENT CLOUD COVER. LIGHT AND VARIABLE WINDS TONIGHT WITH CLEARING SKIES JUST BEFORE SUNSET SHOULD SET UP A GOOD ENVIRONMENT FOR SOME RADIATIONAL COOLING. WITH RELATIVELY HIGHER RH IN THE BOUNDARY LAYER TODAY NOT GETTING MUCH OF A CHANCE FOR MIXING...HAVE PUT FOG IN FOR THE OVERNIGHT IN THE EAST AND SOUTHEAST. CONCERN THAT IT MAY BE MORE WIDESPREAD THAN THE CURRENT PLACEMENT WITH THE DWPTS IN THE WEST STILL NEAR 50. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 310 PM CDT THU APR 16 2015 FRIDAY WILL FEATURE UPPER LEVEL RIDGING AND WARMING ACROSS ILLINOIS, AS A CUT-OFF LOW IN THE PLAINS SLOWLY DRIFTS FROM THE FOUR CORNERS INTO COLORADO. HIGHS WILL REACH INTO THE UPPER 70S IN MANY AREAS FRIDAY AFTERNOON, UNDER A LIGHT SOUTHEAST WIND. RAIN AHEAD OF THE CUT-OFF LOW WILL ADVANCE EASTWARD ACROSS THE PLAINS ON FRIDAY, EXPANDING ACROSS IOWA AND MISSOURI FRIDAY NIGHT AND SATURDAY. CENTRAL ILLINOIS SHOULD REMAIN DRY THROUGH FRIDAY NIGHT, WITH A FEW SHOWERS POSSIBLY AFFECTING AREAS SW OF SPI TO EFFINGHAM ON SATURDAY. INCREASING CLOUDS ON SATURDAY WILL WORK TO KEEP HIGHS A FEW DEGREES BELOW POTENTIAL HIGHS, BUT WE STILL EXPECT MID 70S TO PREVAIL FOR HIGHS. THE LOW WILL BECOME AN OPEN WAVE SATURDAY NIGHT, AS UPPER JET SUPPORT DEVELOPS IN THE LEE OF THE TROUGH. THAT WILL WORK TO INCREASE COVERAGE OF SHOWERS AND A FEW THUNDERSTORMS FROM SOUTHWEST TO NORTHEAST ACROSS CENTRAL ILLINOIS SATURDAY NIGHT. AN INFLUX OF GULF MOISTURE WILL INCREASE LOW LEVEL INSTABILITY THROUGH THE WEEKEND. A BETTER CHANCE OF STRONG TO SEVERE STORMS LOOKS TO BE ON SUNDAY WHEN A SURFACE LOW LIFTS NORTHEAST ACROSS ILLINOIS. THE PASSAGE OF THE UPPER TROUGH AXIS SUNDAY NIGHT WILL CAUSE THUNDERSTORM CHANCES TO LINGER AT LEAST THROUGH MIDNIGHT. SPC HAS WESTERN IL IN THE DAY 4 15 PERCENT SEVERE OUTLOOK, WHICH INCLUDES 12Z SUNDAY TO 12Z MONDAY. WE KEPT LIKELY POPS ACROSS OUR AREA FROM LATE SATURDAY NIGHT THROUGH SUNDAY NIGHT. RAINFALL AND PERSISTENT CLOUD COVER SATURDAY NIGHT THROUGH SUNDAY NIGHT WILL LIMIT DIURNAL TEMP SWINGS. LOWS SAT NIGHT WILL BE IN THE MID TO UPPER 50S, WITH HIGHS NEAR 70 ON SUNDAY. A MORE SIGNIFICANT AIRMASS CHANGE IS EXPECTED TO BEGIN SUNDAY NIGHT BEHIND A DEPARTING SURFACE COLD FRONT. A LONG WAVE TROUGH ALOFT WILL SETTLE INTO THE HEARTLAND, ALLOWING COOLER CANADIAN AIR TO SETTLE INTO OUR AREA. LIGHT RAINFALL WILL LINGER ON MONDAY MORNING, MAINLY EAST OF I-55, BUT CLOUDS SHOULD EVENTUALLY BEGIN TO CLEAR ACROSS WESTERN IL MONDAY AFTERNOON. AN EXTENDED PERIOD OF TEMPS AT OR BELOW NORMAL WILL CONTINUE FROM MONDAY THROUGH AT LEAST WEDNESDAY, AS THE UPPER TROUGH STALLS OVER THE GREAT LAKES AND NW FLOW DOMINATES ALOFT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1157 PM CDT THU APR 16 2015 AREAS MVFR CONDITIONS WITH LOCAL IFR IN FOG FROM AROUND KCMI-K1H2 EASTWARD THIS EVENING...WITH VFR TO THE WEST AS A SURFACE HIGH PRESSURE CENTER REMAINS NEAR THE NORTHEAST CORNER OF THE STATE. FOG WILL SPREAD WESTWARD TO AROUND KBMI-KSPI EASTWARD WHERE GREATEST AMOUNTS OF LOW LEVEL MOISTURE REMAIN ALONG WITH LIGHT WINDS AND LACK OF HIGHER LEVEL CLOUD COVER. WITH DAYTIME HEATING...FOG SHOULD DISSIPATE 13Z-15Z WITH SCATTERED CUMULUS DEVELOPMENT ABOVE MVFR THRESHOLDS. LIGHT SSE WINDS 5-8 KTS DEVELOPING IN THE DAYTIME PERIOD...CONTINUING INTO EVENING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ONTON SHORT TERM...HJS LONG TERM...SHIMON AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
335 AM CDT FRI APR 17 2015 ...UPDATED FOR LONG TERM... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 120 PM CDT THU APR 16 2015 IN THE SHORT TERM, A FEW (2-3) ROUNDS OF CONVECTION ARE ANTICIPATED THROUGH HE NEXT 24 TO 36 HOURS OR SO AS A LARGE UPPER LOW MOVES TOWARD THE REGION WITH FORCING FOR ASCENT, AND PERSISTENT MID LEVEL MOISTURE ADVECTION TO MAINTAIN INSTABILITY FOR A PROLONGED PERIOD. THE FIRST ROUNDS ARE EXPECTED ALREADY EARLY THIS AFTERNOON AS THE NESTED 4 KM NAM AND HRRR MODELS HAVE GENERALLY AGREED ON CONVECTIVE INITIATION BETWEEN AROUND 2 AND 4 PM, AND RAPIDLY DEVELOPING INTO A MULTICELLULAR LINE AFTER AN HOUR OR SO OF SLOWER GROWING DISCREET CELLS. THE INITIAL ROTATING STORMS GENERALLY WEST OF HIGHWAY 83 SHOULD BE CAPABLE OF PRODUCING HAIL LARGER THAN GOLFBALLS AND DAMAGING WIND BEFORE THE STORMS BECOME MORE CLUSTERED OR LINEAR, PRESENTING A SLIGHTLY SMALLER HAIL THREAT AND STILL DAMAGING WIND THREAT THROUGH THE HIGHWAY 283 AND 183 CORRIDORS INTO THE EARLY EVENING HOURS. THESE MODEL SOLUTIONS COULD BE INTERFERED WITH BY THE EXTENSIVE STRATUS ACROSS THE AREA REDUCING THE SEVERE THREAT. ANOTHER ROUND OF THUNDERSTORMS WILL PROBABLY OCCUR LATE TONIGHT INTO THE OVERNIGHT AND POSSIBLY STILL ONGOING EARLY FRIDAY MORNING, WITH A CONTINUED HAIL IF NOT AN ISOLATED WIND THREAT AS WELL, ALTHOUGH SOME BL STABILITY SHOULD HINDER THE WIND THREAT. THE DYNAMICS OF THE UPPER LOW WILL DRIVE A DRY SLOT THROUGH THE REGION OF FRIDAY, BUT NOT BEFORE LATE MORNING/EARLY AFTERNOON DESTABILIZATION CONTRIBUTES TO YET ANOTHER SEVERE EPISODE WITH AS GOOD OR BETTER CAPE AND SHEAR COMBINATIONS. TEMPERATURES WERE RAISED FOR FRIDAY MORNING, FOLLOWING THE NAM AND GFS, AS OVERNIGHT CONVECTION SHOULD LIMIT THE RADIATIONAL COOLING. ADDITIONALLY THE POPS WERE RAISED LOWERED FRIDAY MORNING AND INCREASED ALONG THE MOISTURE TRANSPORT AXIS INTO FRIDAY AFTERNOON WITH A MODEL CONSENSUS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 334 AM CDT FRI APR 17 2015 FOR SATURDAY, THE UPPER LOW IS FORECAST TO MOVE FROM CENTRAL COLORADO AND INTO EASTERN COLORADO BY EVENING. A DRYLINE IS FORECAST TO PUSH TOWARDS DODGE CITY BY LATE AFTERNOON AND EVENING. THE NAM MODEL KEEPS THE DRYLINE FARTHER WEST, WHILE THE GFS PUSHES IT WELL EAST INTO PARTS OF SOUTH CENTRAL KANSAS. TYPICALLY MODELS PUSH THE DRYLINE MORE EAST THAN WHAT ACTUAL HAPPENS SO WILL GO WITH THE NAM FOR NOW THAT AGREES WITH SPC SEVERE SLIGHT RISK FORECAST. CAPES ARE FORECAST TO RUN FROM 1500-2000 J/KG. SOME NEGATIVES FOR WIDESPREAD SEVERE ARE WEAKNESS IN THE MID AND UPPER LEVEL WINDS. SOME SEVERE THUNDERSTORMS ARE POSSIBLE ALONG AND EAST OF THE DRYLINE BY AFTERNOON INTO THE EVENING WITH LARGE HAIL FROM QUARTER TO GOLFBALL WITH THE MID LEVELS FAIRLY COLD AROUND -17 CELSIUS. HIGHS ON SATURDAY WILL RANGE FROM THE UPPER 60S FAR WEST TO THE MID 70 OVER SOUTH CENTRAL SECTIONS OF KANSAS. FOR SATURDAY NIGHT WILL CONTINUE WITH A CHANCE OR SHOWERS AND ISOLATED THUNDERSTORMS WITH OVERNIGHT LOWS IN THE MID AND UPPER 40S. FOR SUNDAY, THE UPPER LOW AND TROUGH MOVES INTO EASTERN KANSAS WITH ONLY SOME LEFT OVER RAIN SHOWERS MAINLY NORTH AND EAST OF DODGE CITY AS A COLD FRONT MOVES ACROSS WESTERN KANSAS. THUNDERSTORMS ARE ALSO POSSIBLE IN THE PARTS OF SOUTH CENTRAL KANSAS WITH BETTER INSTABILITY FROM PRATT AND COLDWATER AND SOUTH. HIGHS ON SUNDAY WILL BE IN THE LOW TO MID 60S. LOWS SUNDAY NIGHT WILL RANGE FROM THE MID 30 NORTH AROUND THE I-70 CORRIDOR TO UPPER 30S AND LOW 40S SOUTH FROM DODGE CITY TO THE OKLAHOMA BORDER. FOR THE PERIOD OF MONDAY INTO THURSDAY, SOME DISTURBANCES IN NORTHWESTERLY FLOW COULD BRING SOME SMALL CHANCES FOR RAIN SHOWERS AND OR THUNDERSTORMS, WITH THE BEST CHANCES TOWARDS WEDNESDAY INTO THURSDAY AS GULF MOISTURE RETURNS. HIGH TEMPS WILL RUN IN THE 60S MONDAY AND TUESDAY, AND AROUND 70 ON WEDNESDAY AND THURSDAY. LOWS WILL RANGE FROM THE UPPER 30S TUESDAY MORNING, THEN INTO THE 40S INTO THURSDAY MORNING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1256 AM CDT FRI APR 17 2015 AREAS OF RAIN AND THUNDERSTORMS WILL AFFECT THE TAF SITES PERIODICALLY THROUGH THE PERIOD. MUCH OF THE TIME, VFR CONDITIONS WILL PERSIST, WITH SOUTHEAST WINDS AT 10 TO 15 KTS OUTSIDE OF THUNDERSTORMS. VISIBILITIES MAY DROP TO MVFR IN ANY THUNDERSTORMS WITH CEILINGS REMAINING VFR/MVFR, EXCEPT FOR IN ANY HEAVIER SHOWERS. && .PRELIMINARY POINT TEMPS/POPS... DDC 71 52 72 46 / 60 60 40 50 GCK 71 48 69 45 / 50 50 30 40 EHA 71 42 68 44 / 10 20 20 30 LBL 71 46 71 46 / 30 40 30 30 HYS 70 56 72 49 / 70 70 50 50 P28 71 56 75 51 / 70 70 40 40 && .DDC WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 2 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING FOR KSZ084. && $$ SHORT TERM...RUSSELL LONG TERM...KRUSE AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1259 AM CDT FRI APR 17 2015 ...UPDATED FOR AVIATION DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 120 PM CDT THU APR 16 2015 IN THE SHORT TERM, A FEW (2-3) ROUNDS OF CONVECTION ARE ANTICIPATED THROUGH HE NEXT 24 TO 36 HOURS OR SO AS A LARGE UPPER LOW MOVES TOWARD THE REGION WITH FORCING FOR ASCENT, AND PERSISTENT MID LEVEL MOISTURE ADVECTION TO MAINTAIN INSTABILITY FOR A PROLONGED PERIOD. THE FIRST ROUNDS ARE EXPECTED ALREADY EARLY THIS AFTERNOON AS THE NESTED 4 KM NAM AND HRRR MODELS HAVE GENERALLY AGREED ON CONVECTIVE INITIATION BETWEEN AROUND 2 AND 4 PM, AND RAPIDLY DEVELOPING INTO A MULTICELLULAR LINE AFTER AN HOUR OR SO OF SLOWER GROWING DISCREET CELLS. THE INITIAL ROTATING STORMS GENERALLY WEST OF HIGHWAY 83 SHOULD BE CAPABLE OF PRODUCING HAIL LARGER THAN GOLFBALLS AND DAMAGING WIND BEFORE THE STORMS BECOME MORE CLUSTERED OR LINEAR, PRESENTING A SLIGHTLY SMALLER HAIL THREAT AND STILL DAMAGING WIND THREAT THROUGH THE HIGHWAY 283 AND 183 CORRIDORS INTO THE EARLY EVENING HOURS. THESE MODEL SOLUTIONS COULD BE INTERFERED WITH BY THE EXTENSIVE STRATUS ACROSS THE AREA REDUCING THE SEVERE THREAT. ANOTHER ROUND OF THUNDERSTORMS WILL PROBABLY OCCUR LATE TONIGHT INTO THE OVERNIGHT AND POSSIBLY STILL ONGOING EARLY FRIDAY MORNING, WITH A CONTINUED HAIL IF NOT AN ISOLATED WIND THREAT AS WELL, ALTHOUGH SOME BL STABILITY SHOULD HINDER THE WIND THREAT. THE DYNAMICS OF THE UPPER LOW WILL DRIVE A DRY SLOT THROUGH THE REGION OF FRIDAY, BUT NOT BEFORE LATE MORNING/EARLY AFTERNOON DESTABILIZATION CONTRIBUTES TO YET ANOTHER SEVERE EPISODE WITH AS GOOD OR BETTER CAPE AND SHEAR COMBINATIONS. TEMPERATURES WERE RAISED FOR FRIDAY MORNING, FOLLOWING THE NAM AND GFS, AS OVERNIGHT CONVECTION SHOULD LIMIT THE RADIATIONAL COOLING. ADDITIONALLY THE POPS WERE RAISED LOWERED FRIDAY MORNING AND INCREASED ALONG THE MOISTURE TRANSPORT AXIS INTO FRIDAY AFTERNOON WITH A MODEL CONSENSUS. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 1152 AM CDT THU APR 16 2015 FRIDAY NIGHT INTO SATURDAY WE WILL STILL BE DEALING WITH THE SLOW- MOVING UPPER LOW, BUT BY THIS TIME THE LOW WILL BE SEVERELY OCCLUDED WITH THE DRY INTRUSION WORKING IN FAST FROM THE SOUTHWEST. IN FACT, FRIDAY NIGHT LOOKS RATHER DRY NOW WITH THE SYNOPTIC DRY INTRUSION ACROSS MUCH OF KANSAS. WE HAVE REDUCED POPS AS A RESULT FRIDAY NIGHT. AS WE HEAD INTO SATURDAY, ANY DAYTIME HEATING WILL PROMOTE SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT AS THE CORE OF THE MID LEVEL CYCLONE WALLOWS SLOWLY EASTWARD INTO FAR WESTERN KANSAS. WE WILL MAINTAIN THE 20-40 POPS ACROSS MAINLY THE NORTHERN AND EASTERN ZONES WITH A DRY FORECAST ACROSS FAR SOUTHWEST KANSAS. WHAT IS LEFT OF THE LOW WILL FINALLY PULL AWAY SATURDAY NIGHT INTO EARLY SUNDAY WITH FAIRLY STRONG NORTH WINDS TO FOLLOW DURING THE DAY SUNDAY. WE COULD STILL SEE SOME WRAP-AROUND LIGHT PRECIPITATION IN THE WEAKENING MID LEVEL DEFORMATION AXIS, HENCE THE 20 TOP 30 POPS FOR MUCH OF THE AREA. LOOKING BEYOND THE WEEKEND, WE WILL ENTER A NORTHWEST FLOW PATTERN ON THE SOUTHWEST SIDE OF A LARGE-SCALE UPPER TROUGH ACROSS THE GREAT LAKES REGION. THE ATMOSPHERE WILL BE FAIRLY COOL EARLY NEXT WEEK AS A RESULT WITH LARGE SCALE HIGH PRESSURE AT THE SURFACE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1256 AM CDT FRI APR 17 2015 AREAS OF RAIN AND THUNDERSTORMS WILL AFFECT THE TAF SITES PERIODICALLY THROUGH THE PERIOD. MUCH OF THE TIME, VFR CONDITIONS WILL PERSIST, WITH SOUTHEAST WINDS AT 10 TO 15 KTS OUTSIDE OF THUNDERSTORMS. VISIBILITIES MAY DROP TO MVFR IN ANY THUNDERSTORMS WITH CEILINGS REMAINING VFR/MVFR, EXCEPT FOR IN ANY HEAVIER SHOWERS. && .PRELIMINARY POINT TEMPS/POPS... DDC 52 69 45 65 / 60 30 40 30 GCK 48 69 44 62 / 60 30 40 30 EHA 42 66 43 62 / 30 20 20 20 LBL 46 69 45 63 / 40 30 30 20 HYS 56 71 48 62 / 60 50 50 40 P28 56 72 51 67 / 60 40 50 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RUSSELL LONG TERM...UMSCHEID AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS JACKSON KY
335 AM EDT FRI APR 17 2015 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME MOIST SOUTHERLY FLOW MOVING INTO KENTUCKY FROM THE SOUTHWEST THIS MORNING. AT THIS TIME...WEAK SURFACE HIGH PRESSURE CENTERED OVER MI IS POISED TO SLOWLY CREEP SOUTHEAST. IN THIS AREA OVER THE LOWER GREAT LAKES...A BIT OF CLEARING MAY MAKE IT INTO EAST KENTUCKY THIS MORNING. THIS COMBINED WITH THE MOISTURE PRESENT OVER THE AREA MAY RESULT IN SOME DENSE FOG DEVELOPMENT TOWARDS DAWN. AT THIS POINT...IT LOOKS LIKE A TOUGH CALL WITH CLOUD COVER CONTINUING TO STREAM IN FROM THE SOUTHWEST. HAVE PUT PATCHY FOG IN THE FORECAST TO COVER THIS BUT WILL ALSO MONITOR FOG DEVELOPMENT TOWARDS DAWN. IN ADDITION TO THIS...A WEAK REMNANT TROUGH SLIDING EAST AHEAD OF HIGH PRESSURE MAY BE ENOUGH TO SPAWN A FEW SHOWERS. HI RES MODELS SUCH AS THE HRRR DO HINT AT THIS INTO THE DAY AS THIS TROUGH SLOWLY SLIDES THROUGH. WITH NO REAL SURFACE FEATURE THIS ACTIVITY IS TIED TO...WILL GO WITH SLIGHT CHANCE POPS THROUGH MIDDAY AND ONLY SHOWERS EXPECTED. HEADING INTO TONIGHT...MENTIONED HIGH PRESSURE WILL MOVE INTO THE AREA TONIGHT. SOME BREAKS IN THE CLOUD COVER IS EXPECTED...ESPECIALLY OVER THE NORTH WHERE SOME CLEAR SKIES LOOK TO DEVELOP. THIS MAY POSE AS A BETTER FOG SET UP AND MAY NEED TO MENTION THIS IN THE HWO. BY SATURDAY...A CLOSED UPPER LOW EJECTS INTO THE CENTRAL PLAINS...AND A SHORTWAVE MOVES OUT OF THE BASE OF THE LOW...CROSSING THE LOWER MS RIVER VALLEY AND NORTHEAST INTO THE OH AND TN VALLEYS. SURFACE LOW PRESSURE AND A DEVELOPING WARM FRONT WILL BRING A SURGE OF MOIST AIR INTO EAST KENTUCKY WITH A SLIGHT CHANCE POPS MAKING MAKING IT INTO POINTS SOUTH OF THE HAL ROGERS PARKWAY BY SATURDAY AFTERNOON. MODELS WITH THIS FEATURE HAVE BEEN PRETTY CONSISTENT AND THE BEST CHANCE OF MEASURABLE PRECIP WILL BE AFTER 00Z SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 335 AM EDT FRI APR 17 2015 CLOSED UPPER LEVEL LOW THAT HAS BEEN QUASI STATIONARY ACROSS THE DESERT SW WILL FINALLY BEGIN PHASING WITH A NORTHERN STREAM TROUGH AS WE MOVE INTO THE LONG RANGE PERIOD. DIFFLUENCE ALOFT...JET ENERGY... AND SHORTWAVE WILL AID IN DEVELOPING SURFACE LOW PRESSURE ACROSS THE SOUTHERN MISSISSIPPI RIVER VALLEY SATURDAY NIGHT. THIS WILL HELP TO SPREAD SHOWERS AND THUNDERSTORMS ACROSS THE REGION AS WE MOVE THROUGH THE DAY ON SUNDAY. MODEL SOUNDINGS WOULD SUGGEST PWATS BETWEEN 1.2 AND AOA 1.4 INCHES DURING THIS PERIOD AS COLUMN SATURATES...THEREFORE SOME OF THESE SHOWERS AND STORMS WILL LIKELY BE MODERATE INTENSITY AT TIMES. GIVEN THE VERY WET ANTECEDENT CONDITIONS WE COULD SEE ISOLATED FLOODING THREAT ONCE AGAIN. THIS WILL DEPEND ON THE DEVELOPMENT AND MOVEMENT OF THE LOW PRESSURE THAT DEVELOPS AND MOVES NORTH NORTHEAST SUNDAY AND ALSO ANY CONVECTION THAT DEVELOPS. THIS UPPER LEVEL SYSTEM DOES LOOK TO PHASE WITH THE NORTHERN STREAM TROUGH AS MENTIONED ABOVE AND A CLOSED UPPER LEVEL LOW DEVELOPS ACROSS THE NORTHERN PLAINS. THIS WILL MAKE FOR A TWO PART SYSTEM AS ANOTHER SURFACE LOW DEVELOPS ACROSS THE UPPER MIDWEST SUNDAY EVENING ASSOCIATED WITH A SPOKE OF ENERGY FROM THE CLOSED UPPER LEVEL LOW. THIS LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION MONDAY AND RESULT IN ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. UP TO THIS POINT WE DO SEE GOOD MODEL AGREEMENT IN REGARDS TO THIS SYSTEM. PASSAGE OF THIS FRONT WILL BREAKDOWN THE PATTERN WITH MORE OF A WESTERLY FLOW AND COOLER AIR USHERED IN BEHIND THE FRONT. AN AREA OF HIGH PRESSURE WILL BUILD TO THE SOUTH WITH HIGHS TEMPS IN THE LOW TO MID 60S AND LOWS IN THE UPPER TO EVEN LOWER 40S TUESDAY INTO WEDNESDAY. MORE DIVERGENCE IN THE MODEL GUIDANCE EXISTS IN THE WEDNESDAY TO THURSDAY TIME FRAME. RIGHT NOW THE GFS AND GFS ENSEMBLE MEAN ARE WETTER THAN THE ECMWF AT THIS POINT. GIVEN THE UNCERTAINTY THAT EXISTS WILL LEAN TOWARD THE MODEL BLEND. THIS WILL BRING SLIGHT POPS ACROSS THE NORTH WEDNESDAY AFTERNOON AND CHANCE TO SLIGHT POPS WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 150 AM EDT FRI APR 17 2015 UPPER AND MID LEVEL CLOUD COVER WILL CONTINUE TO STREAM NORTH INTO THE AREA THROUGH THE NIGHT. SOME WEAK INSTABILITY WILL CONTINUE TO ALLOW SOME LOWER LEVEL CLOUD COVER TO DEVELOP TONIGHT AS WELL AS A FEW SHOWERS. THIS LOOKS TO BE MAINLY ALONG THE SOUTHERN TAF SITES. THE NORTHERN TAF SITES MAY SEE A BREAK IN CLOUD COVER HERE AND THERE. TOWARD DAWN...SOME IFR CLOUD COVER LOOKS TO DEVELOP ACROSS THE AREA AND HAVE PUT THIS INTO THE TAFS. WINDS WILL REMAIN LIGHT THROUGH THE PERIOD. HIGH PRESSURE MOVING IN LATER IN THE TAF PERIOD WILL SHUNT THIS LOWER LEVEL CLOUD COVER TO THE EAST TOWARDS MIDDAY FRIDAY WITH MAINLY CLEAR SKIES OR CIRRUS EXPECTED. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...SHALLENBERGER LONG TERM...DJ AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS JACKSON KY
332 AM EDT FRI APR 17 2015 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME MOIST SOUTHERLY FLOW MOVING INTO KENTUCKY FROM THE SOUTHWEST THIS MORNING. AT THIS TIME...WEAK SURFACE HIGH PRESSURE CENTERED OVER MI IS POISED TO SLOWLY CREEP SOUTHEAST. IN THIS AREA OVER THE LOWER GREAT LAKES...A BIT OF CLEARING MAY MAKE IT INTO EAST KENTUCKY THIS MORNING. THIS COMBINED WITH THE MOISTURE PRESENT OVER THE AREA MAY RESULT IN SOME DENSE FOG DEVELOPMENT TOWARDS DAWN. AT THIS POINT...IT LOOKS LIKE A TOUGH CALL WITH CLOUD COVER CONTINUING TO STREAM IN FROM THE SOUTHWEST. HAVE PUT PATCHY FOG IN THE FORECAST TO COVER THIS BUT WILL ALSO MONITOR FOG DEVELOPMENT TOWARDS DAWN. IN ADDITION TO THIS...A WEAK REMNANT TROUGH SLIDING EAST AHEAD OF HIGH PRESSURE MAY BE ENOUGH TO SPAWN A FEW SHOWERS. HI RES MODELS SUCH AS THE HRRR DO HINT AT THIS INTO THE DAY AS THIS TROUGH SLOWLY SLIDES THROUGH. WITH NO REAL SURFACE FEATURE THIS ACTIVITY IS TIED TO...WILL GO WITH SLIGHT CHANCE POPS THROUGH MIDDAY AND ONLY SHOWERS EXPECTED. HEADING INTO TONIGHT...MENTIONED HIGH PRESSURE WILL MOVE INTO THE AREA TONIGHT. SOME BREAKS IN THE CLOUD COVER IS EXPECTED...ESPECIALLY OVER THE NORTH WHERE SOME CLEAR SKIES LOOK TO DEVELOP. THIS MAY POSE AS A BETTER FOG SET UP AND MAY NEED TO MENTION THIS IN THE HWO. BY SATURDAY...A CLOSED UPPER LOW EJECTS INTO THE CENTRAL PLAINS...AND A SHORTWAVE MOVES OUT OF THE BASE OF THE LOW...CROSSING THE LOWER MS RIVER VALLEY AND NORTHEAST INTO THE OH AND TN VALLEYS. SURFACE LOW PRESSURE AND A DEVELOPING WARM FRONT WILL BRING A SURGE OF MOIST AIR INTO EAST KENTUCKY WITH A SLIGHT CHANCE POPS MAKING MAKING IT INTO POINTS SOUTH OF THE HAL ROGERS PARKWAY BY SATURDAY AFTERNOON. MODELS WITH THIS FEATURE HAVE BEEN PRETTY CONSISTENT AND THE BEST CHANCE OF MEASURABLE PRECIPWILL BE AFTER 00Z SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 THE LONG TERM DISCUSSION WILL BE ISSUED SHORTLY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 150 AM EDT FRI APR 17 2015 UPPER AND MID LEVEL CLOUD COVER WILL CONTINUE TO STREAM NORTH INTO THE AREA THROUGH THE NIGHT. SOME WEAK INSTABILITY WILL CONTINUE TO ALLOW SOME LOWER LEVEL CLOUD COVER TO DEVELOP TONIGHT AS WELL AS A FEW SHOWERS. THIS LOOKS TO BE MAINLY ALONG THE SOUTHERN TAF SITES. THE NORTHERN TAF SITES MAY SEE A BREAK IN CLOUD COVER HERE AND THERE. TOWARD DAWN...SOME IFR CLOUD COVER LOOKS TO DEVELOP ACROSS THE AREA AND HAVE PUT THIS INTO THE TAFS. WINDS WILL REMAIN LIGHT THROUGH THE PERIOD. HIGH PRESSURE MOVING IN LATER IN THE TAF PERIOD WILL SHUNT THIS LOWER LEVEL CLOUD COVER TO THE EAST TOWARDS MIDDAY FRIDAY WITH MAINLY CLEAR SKIES OR CIRRUS EXPECTED. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...SHALLENBERGER LONG TERM...DJ AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS JACKSON KY
151 AM EDT FRI APR 17 2015 .UPDATE... ISSUED AT 150 AM EDT FRI APR 17 2015 ISSUED AN UPDATE TO INPUT THE LATEST TEMPS AND DEW POINTS ACROSS THE AREA. PRECIP HAS NOT REDEVELOPED INTO THE AREA YET BUT EVIDENCE OF A FEW VERY SMALL SHOWERS POPPING JUST NORTH OF THE OH RIVER WILL JUST BE ENOUGH EVIDENCE OF WEAK INSTABILITY TO LEAVE POPS IN FOR SLIGHT CHANCE SHOWERS THROUGH DAWN. A NEW ZFP WILL NOT BE NEEDED WITH THIS UPDATE. UPDATE ISSUED AT 1004 PM EDT THU APR 16 2015 PRECIP HAS DIED OUT OVER THE JKL FORECAST AREA FOR THE TIME BEING. THERE WERE SHOWERS OCCURRING FROM WESTERN KY TO SOUTHWESTERN OH. SHORT RANGE MODELS SUGGEST THIS AREA OF SHOWERS WILL SAG SOUTHEAST AND ADDITIONAL SHOWER DEVELOPMENT WILL ALSO OCCUR OVER EASTERN KY A LITTLE BEFORE DAWN. HAVE USED 20-30 PERCENT POP TO ACCOUNT FOR THIS. MODELS ALSO SHOW A SMALL RESURGENCE OF SHOWERS LATE FRIDAY AFTER SOME DESTABILIZATION OCCURS. IF IT OCCURS...THINK THE ACTIVITY WOULD BE VERY ISOLATED. FORECAST SOUNDINGS SHOW VERY DRY AIR ALOFT THAT THE CONVECTIVE CURRENTS WOULD BE RISING INTO. WITHOUT A STRONG FOCUS/FORCING MECHANISM...DRY AIR ENTRAINMENT COULD BE THE DEMISE OF WHAT WOULD OTHERWISE BE MORE PLENTIFUL ACTIVITY. UPDATE ISSUED AT 615 PM EDT THU APR 16 2015 UPDATED POPS FROM FRIDAY INTO SATURDAY. LATEST MODEL RUNS SUGGEST THE TIME FRAME FROM LATE FRIDAY THROUGH SATURDAY WILL LIKELY BE DRY. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 306 PM EDT THU APR 16 2015 WITH THE LATEST RUN OF THE HRRR MODEL BEING A BIT OFF WITH ITS HANDLING OF TODAYS CONVECTION...THE NAM12 WAS MODEL OF CHOICE FOR THE SHORT TERM PORTION OF THE FORECAST. SHOWERS AND STORMS THAT HAVE BEEN MOVING ACROSS EASTERN KENTUCKY THROUGHOUT THE DAY ARE CURRENTLY AFFECTING THE NORTHEASTERN PORTION OF THE THE AREA. THIS ACTIVITY IS EXPECTED TO MOVE ON OUT OF THE AREA IN THE NEXT FEW HOURS. CURRENT RADAR INDICATES THAT ISOLATED TO SCATTERED SHOWERS AND STORMS WILL CONTINUE TO MOVE INTO THE AREA FROM THE SOUTHWEST DURING THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. ONLY ISOLATED ACTIVITY...IF THAT...WILL BE LEFT OVER FOR THE OVERNIGHT HOURS. SHOWERS AND STORMS WILL BE POSSIBLE DURING THE DAY ON FRIDAY...AS A WEAK FRONTAL BOUNDARY MOVES IN FROM THE WEST. WEAK DISTURBANCES AHEAD OF THIS FRONT MAY ALSO KICK OFF SHOWERS AND STORMS...BUT WITH A LACK OF INSTABILITY AND STRONG LIFT...IT APPEARS THAT THE COVERAGE OF PRECIPITATION WILL BE SPARSE. BASED ON THE LATEST MODEL DATA...THERE SHOULD BE LULL IN THE ACTION FROM LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING...AS A WEAK RIDGE OF HIGH PRESSURE BRIEFLY SETTLES OVER THE AREA. TEMPERATURES DURING THE PERIOD WILL BE WELL ABOVE NORMAL FOR THIS TIME OF YEAR...WITH HIGHS ON FRIDAY MAXING OUT IN THE 70S...AND OVERNIGHT LOWS TONIGHT AND FRIDAY NIGHT BOTTOMING OUT IN THE LOW TO MID 50S AREA WIDE. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 340 PM EDT THU APR 16 2015 MAIN CONCERN DURING THE EXTENDED PERIOD IS FOCUSED ON A CUT OFF LOW CURRENTLY OVER THE FOUR CORNERS REGION. THIS LOW IS PROGGED TO PUSH SLOWLY EWD EARLY SATURDAY BEFORE ITS ENERGY GETS INGESTED AND HELPS DEEPEN A NORTHERN STREAM TROUGH. THIS TROUGH WILL MOVE ALONG THE US/CANADIAN BORDER UNTIL THE CLOSED LOW ENERGY PHASES WITH IT AND MOVES EAST. IN ADDITION TO THE UPPER LEVEL TROUGH...A SFC LOW IS FORECASTED TO DEVELOP SATURDAY NIGHT OVER THE PLAINS AND AHEAD OF IT...A STRONG SURGE OF GULF MOISTURE RETURNS TO THE OH AND TN VALLEYS. PW VALUES UP TO 1.4 INCHES ARE EXPECTED WITH THIS NEW SURGE OF MOISTURE....WHICH ARE WELL ABOVE AVERAGE. THERE WILL BE SOME MODERATE INSTABILITY AS WELL. THIS SYSTEM SHOULD PUSH OUT OF KY BY MONDAY NIGHT. ON TUESDAY...A LOW THAT IS NOW CUT OFF IN THE NORTHERN STREAM WILL UNDULATE OVER THE GREAT LAKES REGION THROUGH THURSDAY WITH PIECES OF ENERGY WRAPPING AROUND IT. HOWEVER...THIS SHOULDN/T CAUSE ANY ISSUES FOR KENTUCKY AS THE ENERGY APPEARS TO STAY FURTHER NORTH UNTIL THURSDAY WHEN THE LOW STARTS SAGGING SOUTHEASTWARD. AT THE SFC...SATURDAY WILL BE MAINLY DRY AND WARM UNTIL LATE AFTERNOON WHEN CHANCES FOR PRECIP BEGIN INCREASING. THE BULK OF THE RAINFALL WILL FALL SUNDAY INTO MONDAY WHERE AT LEAST AN INCH OF LIQUID IS LIKELY ACROSS EASTERN KENTUCKY. THERE IS ALSO A CHANCE FOR THUNDERSTORMS DURING THIS TIME GIVEN THE MOIST AIR MASS IN PLACE AND PLENTY OF SFC/UPPER LEVEL DYNAMICS. AS THIS SYSTEM EXITS THE AREA MONDAY NIGHT...THINGS WILL DRY OUT AND EASTERN KENTUCKY WILL GET A REPRIEVE FROM PRECIPITATION TUESDAY AND WEDNESDAY. TEMPERATURES DURING THIS TIME WILL BE A BIT BELOW NORMAL IF NOT RIGHT AT SEASONABLE LEVELS. RAIN CHANCES RETURN ON THURSDAY AS THE LOW SAGS SOUTHEASTWARD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 150 AM EDT FRI APR 17 2015 UPPER AND MID LEVEL CLOUD COVER WILL CONTINUE TO STREAM NORTH INTO THE AREA THROUGH THE NIGHT. SOME WEAK INSTABILITY WILL CONTINUE TO ALLOW SOME LOWER LEVEL CLOUD COVER TO DEVELOP TONIGHT AS WELL AS A FEW SHOWERS. THIS LOOKS TO BE MAINLY ALONG THE SOUTHERN TAF SITES. THE NORTHERN TAF SITES MAY SEE A BREAK IN CLOUD COVER HERE AND THERE. TOWARD DAWN...SOME IFR CLOUD COVER LOOKS TO DEVELOP ACROSS THE AREA AND HAVE PUT THIS INTO THE TAFS. WINDS WILL REMAIN LIGHT THROUGH THE PERIOD. HIGH PRESSURE MOVING IN LATER IN THE TAF PERIOD WILL SHUNT THIS LOWER LEVEL CLOUD COVER TO THE EAST TOWARDS MIDDAY FRIDAY WITH MAINLY CLEAR SKIES OR CIRRUS EXPECTED. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...AR LONG TERM...JVM AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
359 AM EDT FRI APR 17 2015 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO MOVE OFF THE COAST THIS MORNING. A SURFACE TROUGH WILL PASS THROUGH THE REGION TODAY AND HIGH PRESSURE WILL RETURN FOR SATURDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY AND A WARM FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT INTO MONDAY. A COLD FRONT WILL PASS THROUGH LATE MONDAY INTO MONDAY NIGHT BEFORE HIGH PRESSURE RETURNS FOR THE MIDDLE PORTION OF NEXT WEEK. && .NEAR TERM /THROUGH SATURDAY/... HIGH PRESSURE WILL CONTINUE TO MOVE OFF THE EAST COAST THIS MORNING. AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE MID- ATLANTIC THIS MORNING. WARM AIR ADVECTION COUPLED WITH AN UPPER LEVEL DISTURBANCE HAS ALLOWED SHOWERS TO MOVE ACROSS THE I-95 CORRIDOR THIS MORNING. LESS THAN A QUARTER INCH HAS BEEN REPORTED OVERNIGHT. AN UPPER LEVEL TROUGH WILL SWING THROUGH THE MID- ATLANTIC THIS MORNING AND MOISTURE AND LIFT WILL PUSH OFF THE EAST COAST GIVING WAY TO DRIER CONDITIONS. SHOWERS WILL DIMINISH BY MID- MORNING BUT A SFC TROUGH CURRENTLY ACROSS THE OHIO VALLEY WILL MOVE THROUGH THE REGION TODAY AND INCREASE POTENTIAL FOR MORE SHOWERS. A PERIOD OF DRY CONDITIONS ARE EXPECTED THIS MORNING BETWEEN THE EXITING UPPER LEVEL DISTURBANCE AND INCOMING SFC TROUGH. TEMPS SHOULD RISE INTO THE L-M 70S BY AFTERNOON. NW FLOW WILL DRAW IN COLD DRY AIR ALOFT TODAY. THIS WILL CAUSE LAPSE RATES TO INCREASE AND SHOWERS ARE EXPECTED TO FORM ALONG THE SFC TROUGH BY EARLY AFTERNOON. LATEST HRRR GUIDANCE SHOWS A BKN LINE OF CONVECTIVE SHOWERS TO MOVE E-SE THROUGH THE AFTERNOON. AS THE SHOWERS MOVE PAST I-66...WARMER SFC TEMPS AND DECENT BOUNDARY LAYER MIXING WILL ALLOW A FEW HUNDRED J/KG OF CAPE. A FEW THUNDERSTORMS ARE POSSIBLE SOUTH OF I-66/MD RT50 LATE THIS AFTERNOON AND EARLY EVENING. CLEARING IS EXPECTED BEHIND THE SFC TROUGH INTO THE EVENING. HIGH PRESSURE WILL MOVE INTO THE REGION TONIGHT AND PERSIST SATURDAY. FCST MIN TEMPS INT HE 50S EXPECTED TONIGHT. FULL SUNSHINE WILL ALLOW TEMPS TO RISE INTO THE UPPER 70S TO NEAR 80 IN THE METROS SATURDAY. && .SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/... REGION REMAINS ON THE SOUTHERN PERIPHERY OF HIGH PRESSURE CENTERED JUST NORTH OF THE GREAT LAKES. RIDGING BUILDS IN ALOFT...WITH THE RIDGE AXIS SHIFTING ACROSS THE MID ATLANTIC BY SUN MORNING. OVERALL PATTERN WILL KEEP THE AREA DRY. CLOUDS WILL BEGIN TO INCREASE FROM THE SOUTHWEST AHEAD OF THE NEXT FRONTAL SYSTEM. WINDS WILL LIGHTEN AND BECOME NE OVERNIGHT AS THE HIGH BUILDS SOUTH. && .LONG TERM /MONDAY THROUGH THURSDAY/... 00Z MODEL SUITE CONTINUING WITH A SLOWER PROGRESSION OF THE NEXT FRONTAL SYSTEM...AND THE ARRIVAL TIMING OF THE PCPN. RIDGE AXIS SHIFTS EAST DURING THE DAY SUNDAY AS A DEEPENING CLOSED LOW OVER THE NORTHERN PLAINS BUILDS EAST. BROAD LOW PRESSURE AT THE SFC OVER THE CENTRAL PLAINS BECOMES ORGANIZED DURING HE DAY AS WELL AS IT MOVES INTO THE WESTERN GREAT LAKES...GRADUALLY LIFTING THE ASSOCIATED WARM FRONT TO THE NORTH AND INTO THE MID ATLANTIC. GENERAL CONSENSUS AMONGST THE MODELS KEEPS THE WARM FRONT AT OR JUST SOUTH OF THE VA/NC BORDER THRU SUN NIGHT...WITH PCPN OCCURRING SUN-SUN NIGHT AS A RESULT OF DYNAMIC FORCING ALOFT WITH MULTIPLE MID LVL SHORTWAVES AND STRENGTHENING LLJ AND 250MB JET. PWATS INCRSG TO BETWEEN 1.2-1.4 IN...WHICH COULD RESULT IN PERIODS OF MODERATE TO HEAVY RAIN. SOME UNCERTAINTY STILL EXISTS WITH PCPN TIMING AND TSTM DEVELOPMENT ON MONDAY. WARM FRONT LOOKS TO BE NEAR THE VA/NC BORDER EARLY MONDAY...THEN GRADUALLY LIFTING NORTH DURING THE DAY. HOW QUICKLY IT CAN CLEAR THE CWA AND WARM SECTOR THE AREA WILL AFFECT THE EXTENT OF TSTM DEVELOPMENT...AND AS SUCH WILL CONTINUE TO MENTION SLIGHT CHC T FOR MOST OF THE AREA NOW...AND CHC OVER CENTRAL VA WHERE THE BEST DAYTIME HEATING SHOULD OCCUR. KEPT NORTHEASTERN MD OUT OF THE THUNDER MENTION FOR NOW WITH COOLER TEMPS EXPECTED. IN ADDITION...THINKING THERE SHOULD BE TWO ROUNDS OF PCPN...THE INITIAL SUN NIGHT...WITH A BREAK AT SOME POINT MONDAY WITH THE NEXT ROUND MOVING IN AHEAD OF THE APPROACHING COLD FRONT. THE COLD FRONT PUSHES THROUGH MONDAY NIGHT...WITH PCPN CLEARING TO THE EAST BY EARLY TUES MORNING. SFC HIGH PRESSURE BUILDS IN FROM THE SOUTH IN THE WAKE OF THE FRONT THRU WED...QUICKLY PROGRESSING OFFSHORE BY THURS...AND RESULTING IN BRIEF PERIOD OF DRY WX. THE REGION REMAINS POSITIONED AT THE BASE OF A BROAD UPPER LVL CLOSED LOW...WHICH WILL SEND THROUGH THE NEXT COLD FRONT MIDWEEK...BRINGING THE NEXT CHC FOR PCPN. NEAR NORMAL TEMPS EXPECTED THROUGH THE PERIOD ON WLY FLOW. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... MVFR CONDITIONS POSSIBLE THIS MORNING AS CIGS LOWER BEHIND EXITING SHOWERS. CIGS SHOULD BECOME VFR SHORTLY AFTER SUNRISE AND A PERIOD OF DRY CONDTIONS EXPECTED THROUGH NOON. A SFC TROUGH ACROSS THE OHIO VALLEY WILL MOVE FROM WEST TO EAST ACROSS THE TERMINALS THIS AFTERNOON. SHOWERS WILL REDEVELOP. AN ISOLATED TS IS POSSIBLE MAINLY CHO-DCA. A WIND SHIFT FROM S-SW TO W-NW EXPECTED TODAY. VFR CONDITIONS EXPECTED TONIGHT AND SATURDAY. VFR CONDITIONS SAT NIGHT-SUN. SUB-VFR CONDITIONS BCMG LIKELY BY SUN NIGHT WITH WIDESPREAD RAIN. PERIODS OF HEAVIER RAIN COULD DROP CONDITIONS TO SUB-IFR SUN NIGHT. LLWS CONCERNS PSBL MON MORNING WITH SE WINDS 40-50 KTS AT 2KFT...SHIFTING TO THE SOUTH DURING THE MORNING. SUB-VFR CONDITIONS REMAIN PSBL DURING THE DAY MON AS A COLD FRONT BRINGS ANOTHER ROUND OF PCPN. SLIGHT CHC OF THUNDER CURRENTLY FOR THE TAF SITES...MAINLY MON AFTN/EVENING. WIND SHIFT EXPECTED MON EVENING WITH FRONTAL PASSAGE. VFR CONDITIONS MON NIGHT AS THE PCPN TAPERS OFF...LASTING THRU WED. && .MARINE... SHOWERS WILL MOVE EAST OF THE WATERS BY MID-MORNING. SOUTHERLY CHANNELING IS EXPECTED THIS MORNING AS A PRESSURE GRADIENT TIGHTENS ACROSS THE WATERS. A SCA IS IN EFFECT FOR THE LOWER TIDAL POTOMAC AND MD CHESAPEAKE BAY FOR GUSTS 18-20KTS. A SFC TROUGH WILL CROSS THE WATERS THIS AFTERNOON. SHOWERS ARE EXPECTED AND AN ISOLATED THUNDERSTORM IS POSSIBLE MAINLY ACROSS THE SOUTHERN WATERS. S WINDS BECOME W-NW THIS EVENING. HIGH PRESSURE BUILDS IN TONIGHT AND SATURDAY. GENERALLY SUB-SCA CONDITIONS SAT NIGHT-SUN. SCA CONDITIONS PSBL BY SUN NIGHT WITH INCRSG ELY FLOW. SCA CONDITIONS LAST DURING THE DAY MON AHEAD OF THE COLD FRONT...BCMG SUB-SCA MON EVENING. GUSTS TO 20 KTS PSBL AGAIN TUES AFTN IN THE WAKE OF THE FRONT. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ530>534- 537>543. && $$ SYNOPSIS...SEARS/HAS NEAR TERM...HAS SHORT TERM...HAS LONG TERM...SEARS AVIATION...SEARS/HAS MARINE...SEARS/HAS
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
436 AM CDT Fri Apr 17 2015 .DISCUSSION... Issued at 435 AM CDT FRI APR 17 2015 Today - Tonight: Today will be a transition day. An upper ridge, now overhead, has kept the KS/OK/TX Panhandle convection at bay since yesterday. However, as the upper ridge nudges east this convection will be able to edge closer and closer. This activity has been generated by weak impulses ejecting from a cut-off upper low near the 4-corners area and mid-level frontogenesis. This upper low has moved little over the past 24 hours as it awaits its kicker which is just now crossing into British Columbia. This latter feature is expected to strengthen later today as upstream ridging sharpens and forces this shortwave trough to dig southeast into the Northern Rockies...but not until tomorrow. What this means is any convection reaching the CWA today will weaken/fall apart as it moves away from the better upper support. Having said that there are some signals from the last couple runs of the HRRR and to a lesser extent the 00z NAM that convection now moving east through northern OK/south central KS could reach the far western counties by around the noon hour. Regional radars show an outflow boundary now expanding east from the KS convection with new activity sprouting over north central OK. This activity is what the HRRR picks up on and lifts northeast later this morning. So, will slowly shift chance PoPs across the far western CWA today while leaving the eastern half dry. Convective debris clouds will also thin as they spread east today providing a thin veil of high clouds. This shouldn`t hold back warming and expect temperatures to top out in the middle and upper 70s. The Southern Plateau closed low will gradually shift east tonight, allowing new convection to push further east and become more organized as it reaches the KS/MO state line towards sunrise. Will handle this with a steady and gradual increase in PoPs through the night. Saturday - Sunday: A very wet period with convection becoming numerous and likely coming in waves as cells track nne while shifting slowly east. Model precipitable water values 2 to 3 standard deviations are a cause for concern. Steering winds in the 20kt area plus this moisture heighten the threat of localized flooding. Have increased qpf and this may even be underdone as its certainly feasible that some areas could see up to 2 inches of rain through Saturday night. Extensive cloud cover and rain-cooled air forces me to lower highs on both days and won`t be surprised if they are lowered further in future forecasts. Modest MLCAPEs and 0-6km shear in the 20-30kt range are not likely to support any severe threat on Saturday. Sunday may be a slightly different story. By then the closed upper low will have opened up and accelerated eastward. There is a chance we could be rain free Sunday morning with some partial sunshine. Should this occur more robust afternoon convection could form within a marginally supportive airmass featuring MLCAPEs of 1200-1400 J/kg but only 25-30kt 0-6 km bulk shear. Monday - Friday: The shortwave trough which will act as the kicker to move the current closed upper low near the 4-corners will have formed into a well developed upper trough from the Upper MS Valley through the Mid MO Valley early in this period. As the upper trough axis passes through on Monday strong subsidence and cold air advection will provide ample sunshine but below average temperatures through Tuesday. By mid week, an upper ridge axis will build east into the Central Plains with warm air advection spreading east. The GFS is more aggressive and faster than the ECMWF in pushing weak mid level vorticity lobes through the ridge axis. These features will be ejected from a broad upper trough that will works into the desert southwest. Difficult to determine how soon any scattered convection could work its way back into the region. For now will introduce some low chance PoPs for late Wednesday into Thursday. The current closed upper low now over northern Mexico is expected to weaken as it lifts north-northeast through the Central Plains and CWA. While there should be decent moisture lifted northward with this feature minimal instability will limit amount of thunder. Given that the operational models have been generating a similar solution believe 30-40 PoPs are warranted for scattered convection. Thursday - Sunday: Roll of the dice as to how weather will evolve from Thursday through Sunday. Not especially fond of the blended model approach of carpet bombing chance PoPs in every period. The medium range models drop a deep upper trough into the Desert Southwest and then cut it off. Models typically are challenged significantly with these features initially. They tend to lift them out too soon and too far east. Will be interesting to see how this system is handled going forward. Difficult trying to time any weak impulse ejected from this system within the downstream southwesterly flow. For now will handle this with low chance PoPs with above average temperatures. && .AVIATION...(For the 06Z TAFS through 06Z Friday Night) Issued at 1147 PM CDT THU APR 16 2015 VFR conditions to dominate through much of the fcst period...with winds remaining from the east and southeast between 5-10 kts. Clouds will be on the increase after 15z as long awaited storm system now across the Four Corners region slowly tracks east. Cannot rule out some isolated thunderstorms during the late afternoon...however more concentrated activity will likely hold off until after 00z. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...32
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
332 AM CDT FRI APR 17 2015 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 318 AM CDT FRI APR 17 2015 PCPN CHANCES AND TEMPERATURES ARE THE PRIMARY FORECAST CONCERNS IN THE TODAY PERIOD...THEN CONTINUED SHOWER/THUNDERSTORM CHANCES ESPECIALLY FRIDAY NIGHT THROUGH SATURDAY NIGHT...THEN THE COLD FRONTAL PASSAGE AND PRECIPITATION ENDING SUNDAY. REGIONAL RADAR EARLY THIS MORNING SHOWS AREA OF SHOWERS AND ISOLATED THUNDERSTORMS PIVOTING NORTH TO NORTHWEST FROM KANSAS INTO NEBRASKA AROUND CLOSED UPPER LOW OVER SOUTH CENTRAL COLORADO. WESTERN PORTIONS OF THE FORECAST AREA WILL BE MOST LIKELY TO SEE PRECIP TODAY WITH EASTERN AREAS HAVING TO WAIT UNTIL THE AFTERNOON FOR BETTER POPS AS THE UPPER LOW TRACKS SLOWLY EAST. RAP FORECAST SOUNDINGS SHOW LIMITED INSTABILITY THROUGH MOST OF THE DAY ESPECIALLY IN THE EAST AND NORTH WITH INCREASING INSTABILITY IN WESTERN PARTS OF THE AREA ALONG AND WEST OF A BEATRICE-LINCOLN- COLUMBUS ARC BY LATE AFTERNOON. CLOUD COVER IS EXPECTED TO REMAIN IN PLACE MUCH OF THE DAY FOR THE WEST HALF OF THE AREA WITH VARIABLE SKY COVER IN THE EAST HALF. THIS SPLIT SHOULD SEE LOWER TEMPS AROUND 70 CONFINED TO THE WEST WITH MID 70S IN THE EAST WHERE SOME PERIODS OF SUN ARE POSSIBLE. TONIGHT...THE OPERATIONAL MODELS ARE IN GOOD AGREEMENT THAT THE CLOSED H5 LOW OVER THE FOUR-CORNERS REGION WILL LIFT NORTHEAST TO COLORADO BY 00Z TONIGHT. THE H5 LOW MEANDERS OVER COLORADO THROUGH SATURDAY...THEN DRIFTS INTO WESTERN KANSAS BY 06Z. THE NAM IS SLIGHTLY DIFFERENT IN SPLITTING SOME OF THE H5 ENERGY TO THE NORTH IN SOUTH DAKOTA AND THE CLOSED LOW A LITTLE FARTHER SOUTH TOWARD OKLAHOMA. SHOWERS AND THUNDERSTORMS SHOULD BE ONGOING OVER PARTS OF THE CWA AND WILL CONTINUE TO SPREAD NORTH AND EAST FRIDAY NIGHT AND SATURDAY. THESE PERIODS WILL HAVE THE HIGHEST POPS THIS WEEKEND. THE INSTABILITY AXIS DOES LIFT NORTHWARD FRIDAY NIGHT AND CONTINUES OVER THE AREA SATURDAY. THERE IS ALSO AN H85 BOUNDARY IN THIS REGION THAT LIFTS NORTH AND MAY PROVIDE A FOCUS FOR ENHANCED CONVECTIVE ACTIVITY. SOME .25-.5 INCH RAINS FELL ALONG WITH PEA TO DIME- SIZED HAIL WAS REPORTED WITH SOME OF THE STORMS IN SOUTHERN NEBRASKA THURSDAY NIGHT. FORECAST SOUNDINGS SHOW WEAK INSTABILITY WITH MLCAPE OF 200J/KG FRIDAY NIGHT...AND A LITTLE BETTER INSTABILITY WITH MLCAPE OF 500J/KG SATURDAY. SOME OF THE STRONGER STORMS MAY PRODUCE SOME HAIL. RAINFALL AMOUNTS THROUGH SATURDAY COULD RANGE FROM .5 TO 1 INCH. SATURDAY NIGHT...THE MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TO SHIFT FARTHER EAST INTO IOWA AND EXTEND IN A LARGE AREA FROM THE GULF STATES THROUGH THE MISSISSIPPI VALLEY INTO MINNESOTA AND THE DAKOTA. THE LOW LEVEL JET OF 40-50KTS DEVELOPS OVER IOWA INTO MINNESOTA AND EVENTUALLY WI. THE H85 THERMAL RIDGE IS OVER THE FORECAST AREA. BY 12Z SUNDAY THE GFS/NAM/EC ARE SIMILAR AND HAVE THE SURFACE LOW OVER NORTHEAST NEBRASKA WITH A FRONT OVER FAR EASTERN NEBRASKA INTO WESTERN IOWA. THIS BOUNDARY IS EAST OF THE AREA BY 18Z. WITH THE LONGWAVE TROF STILL MOVING THROUGH THE AREA...THERE WILL STILL BE SCATTERED SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND SUNDAY MORESO IN SOUTHEAST NEBRASKA. NORTHWEST WINDS BEHIND THE FRONT TURN WINDY 15 TO 25KTS AT THE SURFACE WITH 40 TO 50KTS AT H85. THE MOISTURE DRIES OUT TO .5-.75 PWAT BY 00Z AND 0.25 OF AN INCH PWAT BY 12Z MONDAY. .LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 318 AM CDT FRI APR 17 2015 THE CLOSED MID TROPOSPHERIC LOW OVER THE UPPER MISSISSIPPI VALLEY MONDAY...SHIFTS TO THE UPPER GREAT LAKES TUESDAY...AND LINGERS THERE THROUGH THURSDAY. IT SHOULD BE DRY SUNDAY NIGHT THROUGH TUESDAY. HIGHS SHOULD BE IN THE 50S AND 60S. THE GFS IS SLIGHTLY FARTHER NORTH WITH LOW...AND THIS ALLOWS A STORM SYSTEM THAT MOVES INTO THE WESTERN U.S. TO AFFECT THE LOCAL AREA WITH SHOWERS AND ISOLATED THUNDERSTORMS WEDNESDAY INTO THE REST OF THE WEEK. THE EC IS MAINLY DRY THRU THURSDAY. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1149 PM CDT THU APR 16 2015 SCT SHRA MAY AFFECT THE KLNK TAF OVER THE NEXT COUPLE OF HOURS BUT THIS PRECIP WILL HAVE A HARD TIME MOVING NWD TOWARD THE KOMA TAF DUE TO HIGHER STABILITY. SOME OF THIS -RA MAY MOVE INTO KOFK TOWARD MRNG AND WILL INCLUDE A TEMPO GROUP THERE FOR A COUPLE HOURS. MOST OF FRI SHOULD BE DRY FOR THE TAFS WITH A SCT-BKN MID LEVEL CLOUD DECK AND LIGHT WINDS. SCT SHRA MAY AGAIN DVLP FRI EVNG /ESPECIALLY FOR KOFK-KLNK THRU 06Z/ WITH AN EVEN BETTER CHANCE OF PRECIP AT ALL THE TAF SITES JUST AFTER THIS PERIOD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT/ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1253 AM CDT FRI APR 17 2015 .UPDATE... UPDATE ISSUED AT 1253 AM CDT FRI APR 17 2015 UPDATED FORECAST WITH THE CURRENT OBS. LOW TEMPERATURES HAVE BEEN DUMPED DOWN TO REFLECT THE CURRENT OBS AND DEWPOINTS. UPDATE ISSUED AT 1001 PM CDT THU APR 16 2015 AS DISCUSSED BELOW...DRY AIR/LIGHT WINDS/A CLEAR SKY RESULTING IN TEMPERATURES QUICKLY FALLING THROUGH THE 40S. ALREADY SOME MID 30S REPORTED AT HETTINGER AND TIOGA. WILL BUMP OVERNIGHT LOWS DOWN A BIT MORE. PRODUCTS OUT IN THE NEXT 15-20 MINUTES. UPDATE ISSUED AT 639 PM CDT THU APR 16 2015 VERY DRY AIR FILTERING IN FROM THE NORTHWEST. LOWERED DEW POINTS A BIT CLOSER TO THE HRRR WHICH SEEMS TO BEST CAPTURE THIS...TEENS TO LOW 20S WEST AND CENTRAL...30S OVER MY FAR SOUTHEAST. WITH A CLEAR SKY AND WINDS TAPERING OFF...A GOOD SETUP FOR RADIATIONAL COOLING TONIGHT SO DID TWEAK TEMPS DOWN A TAD...LOW 30S OVER MY WEST. MAY NEED TO GO LOWER AND WILL MONITOR TRENDS OVER THE NEXT FEW HOURS. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 256 PM CDT THU APR 16 2015 H500 DEFORMATION ZONE BETWEEN THE CLOSED LOW ALOFT OVER THE FOUR CORNERS AREA AND THE WESTERLY FLOW OVER SOUTHERN CANADA FORMING A REGION OF SINKING/DRYING AIR OVER NORTHERN NORTH DAKOTA. AT THE SURFACE HIGH PRESSURE OVER WYOMING AND MONTANA WILL MOVE EAST. THESE FEATURES WILL CLEAR SKIES ACROSS THE REGION TONIGHT AND FRIDAY. USED THE RAWBLEND GUIDANCE WHICH HAS PERFORMED WELL PAST FEW NIGHT FOR MINIMUM TEMPERATURES. FOR HIGHS FRIDAY FOLLOWED THE EUROPEAN BIAS CORRECTED GUIDANCE. THIS GAVE HIGHS CLOSE TO 70. SEVERAL FACTORS COMBINING TO KEEP RELATIVE HUMIDITY LOW THROUGH THE SHORT TERM. VEGETATION STILL LARGELY DORMANT AND LACK OF SOIL MOISTURE KEEPS EVAPOTRANSPIRATION LOW. SO MAX RELATIVE HUMIDITY TONIGHT SHOULD BE WELL BELOW SATURATION AND IN THE 70S...WITH MIN RELATIVE HUMIDITY FRIDAY AROUND 20 PERCENT. WHAT WILL KEEP FIRE WEATHER CONCERNS LOW WILL BE THE LACK OF WIND. EXPECTING NORTHERLY WINDS AROUND 10 MPH FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 256 PM CDT THU APR 16 2015 A COOL AND DREARY PATTERN THROUGH THE EXTENDED. WIDESPREAD RAINFALL IS LIKELY SATURDAY INTO SUNDAY. OCCASIONAL SPRINKLES ARE POSSIBLE TROUGH TUESDAY. THE UPPER LEVEL LOW CURRENTLY SPINNING AROUND THE FOUR CORNERS REGION OF THE SOUTHWEST CONUS WILL SLOWLY LIFT NORTHEAST OVER THE NEXT COUPLE OF DAYS. THIS LOW WILL TRANSPORT MOISTURE NORTHWARD. MOISTURE WILL COMBINE WITH AMPLE LIFT SUPPLIED BY ANOTHER LOW...AND COLD FRONT...PROPAGATING ACROSS SOUTHERN CANADA THIS WEEKEND. WIDESPREAD RAINFALL IS LIKELY ACROSS PORTIONS OF THE DAKOTAS AND MINNESOTA. AT THIS TIME THE 12 UTC GFS/ECMWF/SREF INDICATE THE HEAVIEST RAINFALL (HALF INCH OR GREATER) WILL FALL ACROSS SOUTHEAST NORTH DAKOTA AND WESTERN MINNESOTA. AS THE TWO LOWS PROPAGATE EASTWARD AND COMBINE THEY SHOULD CREATE A RATHER DEEP AND SLOW MOVING TROUGH ACROSS THE GREAT LAKES BY EARLY NEXT WEEK. IT APPEARS THIS WILL LEAD TO A RATHER STAGNANT PATTERN OVER THE NEXT WEEK WITH GENERALLY COOL AND CLOUDY CONDITIONS FOR MOST OF NORTH DAKOTA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1253 AM CDT FRI APR 17 2015 VFR CONDITIONS WITH MOSTLY CLEAR SKIES AND LIGHT/VARIABLE WINDS ARE EXPECTED THROUGH THE TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AC SHORT TERM...WAA LONG TERM...AJ AVIATION...AC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1206 AM CDT FRI APR 17 2015 .UPDATE... ISSUED AT 1206 AM CDT FRI APR 17 2015 UPDATED FORECAST WITH THE CURRENT OBS...NO MAJOR ADJUSTMENTS NEEDED. WILL CONTINUE TO MONITOR LOW TEMPERATURES. UPDATE ISSUED AT 1001 PM CDT THU APR 16 2015 AS DISCUSSED BELOW...DRY AIR/LIGHT WINDS/A CLEAR SKY RESULTING IN TEMPERATURES QUICKLY FALLING THROUGH THE 40S. ALREADY SOME MID 30S REPORTED AT HETTINGER AND TIOGA. WILL BUMP OVERNIGHT LOWS DOWN A BIT MORE. PRODUCTS OUT IN THE NEXT 15-20 MINUTES. UPDATE ISSUED AT 639 PM CDT THU APR 16 2015 VERY DRY AIR FILTERING IN FROM THE NORTHWEST. LOWERED DEW POINTS A BIT CLOSER TO THE HRRR WHICH SEEMS TO BEST CAPTURE THIS...TEENS TO LOW 20S WEST AND CENTRAL...30S OVER MY FAR SOUTHEAST. WITH A CLEAR SKY AND WINDS TAPERING OFF...A GOOD SETUP FOR RADIATIONAL COOLING TONIGHT SO DID TWEAK TEMPS DOWN A TAD...LOW 30S OVER MY WEST. MAY NEED TO GO LOWER AND WILL MONITOR TRENDS OVER THE NEXT FEW HOURS. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 256 PM CDT THU APR 16 2015 H500 DEFORMATION ZONE BETWEEN THE CLOSED LOW ALOFT OVER THE FOUR CORNERS AREA AND THE WESTERLY FLOW OVER SOUTHERN CANADA FORMING A REGION OF SINKING/DRYING AIR OVER NORTHERN NORTH DAKOTA. AT THE SURFACE HIGH PRESSURE OVER WYOMING AND MONTANA WILL MOVE EAST. THESE FEATURES WILL CLEAR SKIES ACROSS THE REGION TONIGHT AND FRIDAY. USED THE RAWBLEND GUIDANCE WHICH HAS PERFORMED WELL PAST FEW NIGHT FOR MINIMUM TEMPERATURES. FOR HIGHS FRIDAY FOLLOWED THE EUROPEAN BIAS CORRECTED GUIDANCE. THIS GAVE HIGHS CLOSE TO 70. SEVERAL FACTORS COMBINING TO KEEP RELATIVE HUMIDITY LOW THROUGH THE SHORT TERM. VEGETATION STILL LARGELY DORMANT AND LACK OF SOIL MOISTURE KEEPS EVAPOTRANSPIRATION LOW. SO MAX RELATIVE HUMIDITY TONIGHT SHOULD BE WELL BELOW SATURATION AND IN THE 70S...WITH MIN RELATIVE HUMIDITY FRIDAY AROUND 20 PERCENT. WHAT WILL KEEP FIRE WEATHER CONCERNS LOW WILL BE THE LACK OF WIND. EXPECTING NORTHERLY WINDS AROUND 10 MPH FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 256 PM CDT THU APR 16 2015 A COOL AND DREARY PATTERN THROUGH THE EXTENDED. WIDESPREAD RAINFALL IS LIKELY SATURDAY INTO SUNDAY. OCCASIONAL SPRINKLES ARE POSSIBLE TROUGH TUESDAY. THE UPPER LEVEL LOW CURRENTLY SPINNING AROUND THE FOUR CORNERS REGION OF THE SOUTHWEST CONUS WILL SLOWLY LIFT NORTHEAST OVER THE NEXT COUPLE OF DAYS. THIS LOW WILL TRANSPORT MOISTURE NORTHWARD. MOISTURE WILL COMBINE WITH AMPLE LIFT SUPPLIED BY ANOTHER LOW...AND COLD FRONT...PROPAGATING ACROSS SOUTHERN CANADA THIS WEEKEND. WIDESPREAD RAINFALL IS LIKELY ACROSS PORTIONS OF THE DAKOTAS AND MINNESOTA. AT THIS TIME THE 12 UTC GFS/ECMWF/SREF INDICATE THE HEAVIEST RAINFALL (HALF INCH OR GREATER) WILL FALL ACROSS SOUTHEAST NORTH DAKOTA AND WESTERN MINNESOTA. AS THE TWO LOWS PROPAGATE EASTWARD AND COMBINE THEY SHOULD CREATE A RATHER DEEP AND SLOW MOVING TROUGH ACROSS THE GREAT LAKES BY EARLY NEXT WEEK. IT APPEARS THIS WILL LEAD TO A RATHER STAGNANT PATTERN OVER THE NEXT WEEK WITH GENERALLY COOL AND CLOUDY CONDITIONS FOR MOST OF NORTH DAKOTA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 639 PM CDT THU APR 16 2015 A FEW HIGH CLOUDS ACROSS THE NORTH MOVING THROUGH TONIGHT...OTHERWISE A CLEAR SKY AND VFR CONDITIONS THROUGH THE 00Z PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AC SHORT TERM...WAA LONG TERM...AJ AVIATION...NH
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
336 AM CDT FRI APR 17 2015 .DISCUSSION... BROAD SOUTHWEST FLOW ALOFT REMAINS IN PLACE ACROSS THE MID SOUTH TODAY OUT AHEAD OF A LARGE UPPER LEVEL LOW PRESSURE SYSTEM SPINNING OVER THE FOUR CORNERS REGION OF THE INTERMOUNTAIN WEST. DEEPER MOISTURE REMAINS IN PLACE ACROSS THE SOUTHERN HALF OF THE FORECAST AREA TO THE SOUTH OF AN INVERTED SURFACE TROUGH THAT REMAINS STRETCHED ACROSS NORTHERN PORTIONS OF THE REGION. A MID LEVEL SHORTWAVE NOTED FROM WATER VAPOR IMAGERY OVER THE ARKLATEX EARLY THIS MORNING WILL CONTINUE TO LIFT NORTHEAST TODAY. THIS SHOULD COMBINE WITH INCREASING INSTABILITY TO SUPPORT HIGH END CHANCES FOR SHOWERS AND THUNDERSTORMS BASICALLY ALONG AND SOUTH OF INTERSTATE 40. CHANCES DECREASE WITH NORTHERN EXTENT AS OVERALL MOISTURE DECREASES. AS THE SHORTWAVE MOVES EAST OF THE REGION TONIGHT AND INSTABILITY WANES...CONVECTION SHOULD DIMINISH. A STRONGER MID LEVEL SHORTWAVE SHOULD EJECT OUT OF THE SOUTHERN PLAINS AND ACROSS THE MID SOUTH ON SATURDAY AND SATURDAY NIGHT. ENHANCED MOISTURE AND LIFT FROM THIS FEATURE SHOULD SUPPORT LIKELY TO CATEGORICAL CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE REGION BY SATURDAY AFTERNOON AND AREAWIDE SATURDAY NIGHT. PERIODS OF HEAVY RAINFALL WILL BE POSSIBLE DURING THIS TIME PERIOD AS RICH MOISTURE SPREADS NORTH FROM THE GULF OF MEXICO. CONSIDERING THE RECENT WET PATTERN OF LATE...SOME FLOODING CONCERNS WILL DEVELOP LATER SATURDAY AND SATURDAY NIGHT. A FLOOD WATCH MAY BE NEEDED IN LATER FORECASTS IF THIS TREND CONTINUES. THE UPPER LEVEL LOW PRESSURE WILL FINALLY LIFT NORTHEAST ACROSS THE MISSISSIPPI RIVER VALLEY AS AN OPEN WAVE BY SUNDAY AND SUNDAY NIGHT. THIS SHOULD FORCE A COLD FRONT EAST ACROSS THE REGION SUNDAY NIGHT. THE ATMOSPHERE SHOULD DESTABILIZE ACROSS THE REGION BY SUNDAY AFTERNOON AND EVENING AS THE UPPER TROUGH OVERSPREADS THE REGION. THIS SHOULD SUPPORT THE DEVELOPMENT OF ADDITIONAL SHOWERS AND THUNDERSTORMS ALONG AND AHEAD OF THE FRONT. THE ENVIRONMENT APPEARS TO BECOME MORE SUPPORTIVE OF SEVERE STORM DEVELOPMENT DURING THIS TIME PERIOD AS DEEP LAYER SHEAR INCREASES AND LAPSE RATES STEEPEN. STORM MODE APPEARS TO INITIALLY SUPPORT A MIX OF SHORT LINE SEGMENTS AND POTENTIALLY SUPERCELLS WHICH QUICKLY CONGEAL INTO A SQUALL LINE AS MID LEVEL FORCING STRENGTHENS. IT STILL REMAINS A BIT EARLY TO FORECAST OVERALL THREATS WITH CERTAINTY THIS FAR OUT...BUT WILL BEGIN TO MENTION THIS SEVERE WEATHER THREAT IN THE LATEST HAZARDOUS WEATHER OUTLOOK. THE FRONT SHOULD SWEEP EAST OF THE REGION BY EARLY MONDAY MORNING WITH ANY LINGERING SHOWERS AND THUNDERSTORMS ACROSS THE EAST ENDING. MUCH DRIER AND SLIGHTLY COOLER CONDITIONS WILL MOVE INTO THE REGION FOR EARLY NEXT WEEK AS HIGH PRESSURE BUILDS OVERHEAD. PLEASANT SPRING WEATHER WITH SLIGHTLY BELOW AVERAGE TEMPERATURES WILL PERSIST FROM MONDAY THROUGH WEDNESDAY OF NEXT WEEK. A MORE UNSETTLED AND MOISTER WEATHER PATTERN SHOULD BECOME ESTABLISHED ACROSS THE MID SOUTH ONCE AGAIN BY THE END OF NEXT WEEK. JLH && .AVIATION... 06Z TAF CYCLE STRATUS IS CURRENTLY SPREADING NW ACROSS THE CWA. KTUP IS ALREADY EXPERIENCING IFR CIGS AND EXPECT KMKL AND KMEM TO SEE THEM BY 7Z. MEANWHILE...EXPECT SOME FOG TO BEGIN DEVELOPING AT KJBR AND CONDITIONS SHOULD DETERIORATE RAPIDLY TO VLIFR. STRATUS AND FOG MAY BE SLOW TO LIFT IN THE MORNING. LATEST HRRR SHOWS SHRAS POSSIBLY A FEW TSRAS DEVELOPING ACROSS N MS AROUND 15Z THAT WILL SPREAD NORTH AND EAST INTO THE KMEM AND KTUP AREA THROUGH AT LEAST 20-21Z. LIGHT AND VARIABLE WINDS EXPECTED THROUGH THE PERIOD. KRM && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1221 AM CDT FRI APR 17 2015 .UPDATE... UPDATED TO ADD 06Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 909 PM CDT THU APR 16 2015/ UPDATE...EVENING UPDATE. DISCUSSION... DECREASED POPS BASED ON RADAR COVERAGE. SHORT TERM GUIDANCE HAS BEEN PRETTY ACCURATE LATELY...AND IT HAS MORE DEVELOPMENT ACROSS EAST ARKANSAS AND NORTH MISSISSIPPI TOWARD MORNING. TEMPERATURES ARE ON TRACK. PREV DISCUSSION... /ISSUED 650 PM CDT THU APR 16 2015/ DISCUSSION... /ISSUED 307 PM CDT THU APR 16 2015/ SKIES ARE MOSTLY SUNNY OVER A LARGE PORTION OF THE FORECAST AREA THIS AFTERNOON WITH TEMPERATURES RANGING FROM THE UPPER 60S TO LOWER 80S. A FEW SHOWERS AND ISOLATED THUNDERSTORMS WERE MOVING ACROSS PORTIONS OF NORTHEAST MISSISSIPPI AT THIS TIME. THIS ACTIVITY HAS FORMED NEAR A WEAK FRONTAL BOUNDARY WHICH EXTENDS FROM CENTRAL MISSISSIPPI THROUGH SOUTHEAST ALABAMA AND INTO NORTH FLORIDA. THIS BOUNDARY IS EXPECTED TO LIFT NORTH TONIGHT AND AS IT DOES ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP WITH THE BEST CHANCE OF THUNDERSTORMS EXPECTED OVER NORTHEAST MISSISSIPPI. TEMPERATURES WILL REMAIN ON THE WARM SIDE WITH LOWS FRIDAY MORNING IN THE UPPER 50S TO MID 60S. BY FRIDAY MORNING THE BOUNDARY WILL RETREAT BACK SOUTH WITH ADDITIONAL SHOWERS AND THUNDERSTORMS EXPECTED TO DEVELOP MAINLY OVER PORTIONS OF NORTH MISSISSIPPI. TEMPERATURES WILL REMAIN ON THE WARM SIDE WITH HIGHS IN THE UPPER 70S TO AROUND 80 DEGREES. BY FRIDAY NIGHT...AN UPPER LEVEL LOW WILL BE MOVING SLOWLY OUT OF THE CENTRAL ROCKIES AND INTO THE PLAINS. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF THIS SYSTEM WITH SOME OF THIS ACTIVITY POSSIBLY MOVING INTO MAINLY WESTERN SECTIONS OF THE FORECAST AREA. ON SATURDAY AS THE UPPER LOW PUSHES FURTHER EAST THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL INCREASE FOR SATURDAY AND SATURDAY NIGHT. BY SUNDAY...A COLD FRONT WILL BE MOVING INTO EASTERN OKLAHOMA AND WESTERN ARKANSAS SO MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED. THE COLD FRONT WILL MOVE THROUGH THE FORECAST AREA SUNDAY NIGHT WITH ADDITIONAL SHOWERS AND THUNDERSTORMS. THERE MAY ALSO BE A SMALL CHANCE OF SEVERE THUNDERSTORMS AHEAD OF THE FRONT. COOLER AND DRIER AIR WILL MOVE INTO THE REGION BEHIND THE FRONT ON MONDAY BRINING AN END TO THE THREAT OF THUNDERSTORMS WITH TEMPERATURES DROPPING BACK CLOSER TO NORMAL LEVELS. DRY WEATHER WILL CONTINUE INTO TUESDAY AND WEDNESDAY AS WELL WITH HIGH PRESSURE REMAINING IN CONTROL. TEMPERATURES WILL REMAIN NEAR NORMAL LEVELS. ANOTHER COLD FRONT IS EXPECTED TO DROP SOUTH INTO THE CENTRAL PLAINS AND OHIO VALLEY WEDNESDAY NIGHT AND NEXT THURSDAY. THIS WILL BRING ANOTHER CHANCE OF SHOWERS FOR WEDNESDAY NIGHT AND A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS FOR NEXT THURSDAY. ARS && .AVIATION... 06Z TAF CYCLE STRATUS IS CURRENTLY SPREADING NW ACROSS THE CWA. KTUP IS ALREADY EXPERIENCING IFR CIGS AND EXPECT KMKL AND KMEM TO SEE THEM BY 7Z. MEANWHILE...EXPECT SOME FOG TO BEGIN DEVELOPING AT KJBR AND CONDITIONS SHOULD DETERIORATE RAPIDLY TO VLIFR. STRATUS AND FOG MAY BE SLOW TO LIFT IN THE MORNING. LATEST HRRR SHOWS SHRAS POSSIBLY A FEW TSRAS DEVELOPING ACROSS N MS AROUND 15Z THAT WILL SPREAD NORTH AND EAST INTO THE KMEM AND KTUP AREA THROUGH AT LEAST 20-21Z. LIGHT AND VARIABLE WINDS EXPECTED THROUGH THE PERIOD. KRM && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1201 AM CDT FRI APR 17 2015 .UPDATE...FOR 06Z AVIATION DISCUSSION. && .AVIATION...06Z AVIATION DISCUSSION. SEVERAL ADMS POSSIBLE THRU AT LEAST 17/15Z DUE TO CEILING FORMATION/ FLUCTUATIONS AND FOG FORMATION POTENTIALLY LIMITING VSBYS. UPPER LEVEL RIDGING INFLUENCES SHOULD AMPLIFY THRU 18/06Z ALSO AND SHOULD LIMIT CONVECTION POTENTIAL AT TAF SITES...AS SHORT RANGE MODELS SHOWING LITTLE IN THE WAY OF CONVECTION AFFECTING TAF SITES THRU 17/12Z. EXPECT MVFR CEILINGS BNA/CSV TO PERSIST THRU AT LEAST 17/15Z. THERE SILL MAYBE ENOUGH BELIEVE THAT THERE MAYBE ENOUGH CLRING...ESPECIALLY ACROSS NW PORTIONS OF THE MID STATE...WITH LIGHT WINDS FOR PATCHY FOG DEVELOPMENT...FOR MVFR TO IFR FOG POSSIBLE...WITH TEMPO LIFR VSBYS POSSIBLE BNA/CSV. EXPECT FOG DISSIPATION AFTER 17/15Z WITH DISSIPATION IN MVFR/IFR CEILINGS GENERALLY AFTER 17/18Z. EXPECT VFR AC/CI CEILINGS AFTER 18/02Z AS UPPER LEVEL RIDGING INFLUENCES BECOME EVEN MORE ENHANCED. && .PREV DISCUSSION.../ISSUED 822 PM CDT THU APR 16 2015/ DISCUSSION... RADAR IS PRECIP FREE AT THIS TIME BUT CLOUDINESS STILL BLANKETS MUCH OF THE AREA. MOISTURE IN THE FORM OF SHOWERS AND THUNDERSTORMS DOES EXIST TO OUR SOUTH AND SOUTHWEST ACROSS MS AND AL. LATEST HRRR DOES INDICATE THAT SOME OF THIS MOISTURE MAY APPROACH OUR SOUTHWESTERN AREAS TOWARD 12Z. UPPER LEVEL PATTERN CONTINUES TO FLOW FROM THE SOUTHWEST. WE ARE EXPECTING SOME AMPLIFICATION OF A SE-NW UPPER RIDGE BY TOMORROW, BEFORE THAT HAPPENS HOWEVER...ONE MORE WEAK DISTURBANCE WILL RIDE NORTHEASTWARD AND JUST ENOUGH UPPER DIVERGENCE MAY HELP PRODUCE THAT AFOREMENTIONED ACTIVITY TOWARD 12Z. OTW...DEWPOINT DEPRESSIONS ARE VERY LOW CURRENTLY. NUMERICAL DATA DOES SUGGEST SOME LOW VSBY CATS. THUS...WILL GO AHEAD AND ADD PATCHY FOG AREA WIDE FOR AFT 06Z. ADDITIONALLY...WILL OPT TO LOWER POPS TO 20 PERCENT FOR THE ENTIRE MID STATE EXCEPT FOR OUR SOUTHWEST...WHERE POPS WILL REMAIN AT 30 PERCENT. JUST SHOWERS TONIGHT...NO T EXPECTED. PREV DISCUSSION... /ISSUED 652 PM CDT THU APR 16 2015/ UPDATE...FOR 00Z AVIATION DISCUSSION. AVIATION...00Z AVIATION DISCUSSION. SEVERAL ADMS POSSIBLE THRU 17/24Z DUE TO CEILING FORMATION/FLUCTUATIONS AND FOG FORMATION POTENTIALLY LIMITING VSBYS. UPPER LEVEL RIDGING INFLUENCES SHOULD AMPLIFY THRU 17/24Z ALSO AND SHOULD LIMIT CONVECTION POTENTIAL AT TAF SITES...AS SHORT RANGE MODELS SHOWING LITTLE IN THE WAY OF CONVECTION THRU 17/12Z. EXPECT MVFR CEILINGS BNA AND CSV TO PERSIST THRU AT LEAST 17/15Z. WITH MOISTURE RICH AIRMASS GENERALLY IN PLACE...BELIEVE THAT THERE MAYBE ENOUGH CLRING...ESPECIALLY ACROSS CNTRL/NW PORTIONS OF THE MID STATE...WITH LIGHT WINDS FOR PATCHY FOG DEVELOPMENT...FOR MVFR TO IFR FOG POSSIBLE...WITH TEMPO LIFR VSBYS POSSIBLE BNA/CSV. EXPECT FOG DISSIPATION AFTER 17/15Z WITH DISSIPATION IN MVFR/IFR CEILINGS AFTER 17/18Z...BUT FOR TAF BREVITY CONCERNS... DID NOT MENTION IN TAF FORECAST AS THIS TIME. PREV DISCUSSION.../ISSUED 318 PM CDT THU APR 16 2015/ SHORT TERM...SKIES REMAINED MOSTLY CLOUDY INTO THE EARLY AFTERNOON OVER EASTERN AND SOUTHERN PARTS OF THE MID-STATE. MEANWHILE, SKIES BECAME PARTLY CLOUDY OVER THE WEST. AS USUAL FOR THIS TIME OF YEAR, TEMPS WERE QUICK TO WARM UP ONCE THE SUN POPPED OUT AND AT 2 PM, CLARKSVILLE WAS EXPERIENCING A TOASTY 74 DEGREES. TEMPERATURES WERE STRUGGLING A BIT MORE IN THE MOSTLY CLOUDY AREAS, WITH 2 PM READINGS MAINLY IN THE MIDDLE AND UPPER 60S OVER EASTERN AND CENTRAL AREAS. THE SHORTWAVE THAT BROUGHT US THE ROUND OF SHOWERS AND THUNDERSTORMS LAST NIGHT AND THIS MORNING, WAS CROSSING THE OHIO VALLEY THIS AFTERNOON AND PUSHING MOST THE SHOWERS AND THUNDERSTORMS TO THE EAST OF OUR FORECAST AREA. HOWEVER, SINCE THE UPPER LEVEL DISTURBANCE WAS PASSING SO FAR TO OUR NORTH, A BAND OF RELATIVELY DEEP MOISTURE WAS SLOW TO PUSH OUT OF OUR EASTERN AND SOUTHERN COUNTIES. AS A RESULT, BY EARLY AFTERNOON SOME SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS REMAINED ALONG THE CUMBERLAND PLATEAU AND IN AREAS CLOSE TO THE ALABAMA BORDER. IT STILL LOOKS LIKE WE`LL GET A TEMPORARY BREAK TONIGHT THROUGH SATURDAY MORNING FROM THE MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY THAT WE`VE SEEN OVER RECENT DAYS. IN ADDITION, AS CLOUDS DIMINISH FRIDAY NIGHT, BELIEVE OUR SOGGY WET GROUND WILL AID THE DEVELOPMENT OF AREAS OF FOG--SOME OF WHICH COULD BECOME LOCALLY DENSE. ANOTHER SWATH OF DEEP MOISTURE SWINGS NORTHEASTWARD ACROSS THE AREA SATURDAY AFTERNOON AND SATURDAY NIGHT, BRINGING ANOTHER ROUND OF SHOWERS AND STORMS AND THE POTENTIAL FOR LOCALLY HEAVY RAINFALL. SINCE THE RESPONSIBLE SHORTWAVE SHEARS OFF ONCE AGAIN TO THE NORTH, THE RAIN IS SLOWER TO CLEAR OUT OF OUR EASTERN AREAS, AND THE CUMBERLAND PLATEAU COULD SEE SHOWERS AND THUNDERSTORMS FOR A GOOD PART OF SUNDAY AS WELL. ANOTHER INCH OR SO OF RAIN WILL LIKELY OCCUR, SOME OF WHICH WILL COME IN DOWNPOURS. SINCE GROUNDS WILL SILL BE PRETTY SOGGY BY THEN, EXPECT RUN OFF TO PRODUCE PONDING OF WATER IN URBAN LOCATIONS (LIKE NASHVILLE) AND IN LOW LYING AREAS. AFTER THE RAIN PASSES EAST OF OUR AREA SUNDAY EVENING, LOOK FOR A COLD FRONT TO SWEEP ACROSS THE AREA SUNDAY NIGHT AND MONDAY MORNING, BRINGING ANOTHER ROUND OF RAIN. THIS WILL PROBABLY COME ACROSS THE AREA AS A RELATIVELY FAST-MOVING BAND OF SHOWERS AND THUNDERSTORMS, AND BRIEF HEAVY DOWNPOURS MAY ONCE AGAIN OCCUR, AND CAUSE SOME PONDING IN LOW LYING SPOTS AND URBAN AREAS. HOWEVER, THE STORMS AND SHOWERS SHOULDN`T LAST LONG, AND BY MONDAY AFTERNOON WE SHOULD BE DRYING OUT PRETTY WELL, AS HIGH PRESSURE BUILDS IN FROM THE WEST. LONG TERM...A DRY SHORTWAVE SWINGS IN MONDAY NIGHT, DEEPENING AN UPPER LEVEL TROUGH OVER THE GREAT LAKES AND TENNESSEE VALLEY. SOME PATCHY CLOUDS WILL SPREAD ACROSS THE AREA, BUT DON`T EXPECT ANYTHING MORE THAN SOME LIGHT SPRINKLES. BY SUNRISE TUESDAY, COOLER AIR WILL HAVE WORKED IN FROM THE NORTHWEST AND WE`LL BE LOOKING AT TEMPERATURES IN THE MIDDLE AND UPPER 40S. DRY AND COOL WEATHER LINGERS INTO WEDNESDAY, WITH LOWS IN THE 40S AND HIGHS FROM THE MID 60S TO MID 70S. ATMOSPHERIC MOISTURE INCREASES AGAIN BY LATE NEXT WEEK, CREATING THE CHANCE FOR MORE SHOWERS AND THUNDERSTORMS. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1215 AM CDT FRI APR 17 2015 .DISCUSSION... 06Z TAF DISCUSSION IN AVIATION SECTION... && .AVIATION... CONVECTION STILL ONGOING SO START TARS WITH TSRA/VCTS UNTIL 09Z WHEN HRRR TRENDS SHOW CONVECTION ENDING. SHOULD HAVE MVFR TYPE CITS AFTER THAT WITH RAIN COOLED AIRMASS BUT NOT MUCH OTHER CLEARING. CIGS LIFT TO VFR LATE MORNING THROUGH AFTERNOON. BASED ON GFS/ECMWF AND WRF RUNS...POSSIBLE MCS MOVING INTO THE AREA LATE EVENING/FRI NIGHT TIME FRAME. START VCTS AT 22Z UNTIL 04Z TO HIGHLIGHT THAT THREAT. 39 && .PREV DISCUSSION... /ISSUED 953 PM CDT THU APR 16 2015/ UPDATE... VERY BUSY EVENING AS ADVERTISED. CATEGORICAL POPS IN ORDER THROUGH MID NIGHT AREA WIDE...OUTSIDE OF THE COAST/SWRN COUNTIES BEHIND MAIN AREA OF CONVECTION. LATEST MESO ANALYSIS INDICATES PRIMARY/EFFECTIVE WARM FRONT ESTABLISHED ROUGHLY ALONG AND JUST SOUTH OF I-10 WITH ABUNDANT MOISTURE /SURFACE DEWPOINTS IN THE LOWER 70S/ IN PLACE ACROSS THE WARM SECTOR. SPC HAS TORNADO WATCH IN EFFECT AS ACTIVITY NEAR AND SOUTH OF THIS FRONT INGESTS MODERATELY UNSTABLE AND WEAKLY CAPPED WARM SECTOR AIR. THIS WILL INCREASE THE POTENTIAL FOR SPIN UPS UNTIL THE WARM SECTOR ITSELF BEGINS TO CAP OFF LATER TONIGHT. IMPRESSIVE FEED OF MOISTURE WILL SUSTAIN THREAT OF HEAVY RAIN WITH ANY ACTIVITY AREA WIDE. CURRENTLY FFA IS CONFINED TO THE WARM SECTOR WHERE MOST ABUNDANT FEED OF MOISTURE SHOULD CONFINE THE MOST INTENSE RAINFALL RATES. HOWEVER FLOODING REMAINS A CONCERN AREA WIDE GIVEN THE EVENING RAINFALL ACROSS SOME NRN AREAS. THUS...FEEL FFA IS WARRANTED ACROSS THE CWA THROUGH THE DAY TOMORROW AND WILL EXPAND. WITH ANOTHER POSSIBLE LATE DAY/EVENING MCS...FFA MAY NEED TO BE EXTENDED IN LATER FORECASTS THROUGH THE NIGHT FRIDAY/SATURDAY MORNING. PREV DISCUSSION... /ISSUED 659 PM CDT THU APR 16 2015/ DISCUSSION... 00Z TAF DISCUSSION IN AVIATION... AVIATION... MAIN CONCERN IS OBVIOUSLY CONVECTION. LOOKS LIKE CONVECTION WILL BE ENDING THROUGH 02-03Z...WILL HOLD ONTO VCTS/TSRA FOR MOST TAF SITES AS CONVECTION WANES. BASED ON HRRR TRENDS MAY KEEP SOME VCSH GOING THROUGH THE NIGHT IF ANYTHING RE-DEVELOPS. CONFIDENCE IS NOT VERY HIGH ON THIS SO ANTICIPATE AMMENDING TAFS TO REMOVE CONVECTION IN THE SHORT TERM. CIGS SHOULD BE VFR/MVFR OVERNIGHT INTO TOMORROW MORNING. BASED ON WRF-ARW/TX TECH WRF AND EVEN SUPPORTED BY GFS...EXPECT LARGE MCS TO MOVE INTO THE AREA IN THE EVENING SO ADDED MENTION OF VCTS FOR TAFS. STILL TIME TO WORK OUT THESE DETAILS AND LIKELY BE FOCUS OF 06Z TAFS. 39 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 66 79 63 83 59 / 60 50 40 20 20 HOUSTON (IAH) 67 80 64 84 63 / 60 50 40 20 20 GALVESTON (GLS) 70 76 69 78 68 / 60 50 40 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA... MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER... WALLER...WASHINGTON...WHARTON. GM...SMALL CRAFT ADVISORY UNTIL 4 AM CDT EARLY THIS MORNING FOR THE FOLLOWING ZONES: GALVESTON BAY...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. && $$ DISCUSSION...33 AVIATION/MARINE...39
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND SATURDAY ISSUED AT 400 AM CDT FRI APR 17 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK COLD FRONT SLOWLY MOVING TO THE SOUTHEAST OVER FAR NORTHWEST WISCONSIN. AHEAD OF THE FRONT...AREAS OF BROKEN MID-CLOUDS ARE MOVING TO THE EAST OVER CENTRAL AND NORTHERN WISCONSIN. CLEAR SKIES EXIST BEHIND THIS FRONT OVER THE NORTHERN PLAINS. MEANWHILE...SHOWERS AND THUNDERSTORMS ARE OCCURRING OVER THE CENTRAL PLAINS AHEAD OF AN UPPER LOW SPINNING OVER THE 4 CORNERS REGION. FORECAST CONCERNS INCLUDE HIGH TEMPS AND LOW HUMIDITIES FOR SATURDAY. TODAY...THE COLD FRONT WILL SLOW AS IT WEAKENS OVER THE NORTHWEST THIRD OF THE STATE. SCATTERED TO BROKEN MID-LEVEL CLOUD DECK WILL GRADUALLY DISSIPATE THROUGH THE MORNING AS SUBSIDENCE STRENGTHENS OVERHEAD. WILL STILL BE SOME RESIDUAL MOISTURE LEFT AROUND 800MB...HOWEVER...THAT WILL TURN INTO A CU FIELD BY LATE MORNING OVER CENTRAL TO NORTHEAST WISCONSIN. FAR NORTHERN WISCONSIN WILL SEE AN INFLUX OF DRIER AIR DURING THE AFTERNOON...WHICH WILL DROP HUMIDITIES INTO THE 20 TO 25 PCT RANGE. HUMIDITIES SHOULD BE ABOVE CRITICAL CRITERIA ELSEWHERE. RAISED HIGH TEMPS BASED ON 925MB TEMPS ON THE BETTER PERFORMING NAM AND ECMWF...AND MAY NOT BE HIGH ENOUGH. TEMPS TO MAX OUT TO NEAR 70 NORTH TO THE UPPER 70S IN THE WARM SPOTS. TONIGHT...THE WEAKENING FRONT WILL DROP ACROSS CENTRAL AND NORTHEAST WISCONSIN DURING THE EVENING WHILE A SECONDARY AND MORE POTENT FRONT QUICKLY MOVES SOUTH ACROSS NORTHERN AND CENTRAL WISCONSIN AFTER MIDNIGHT. BEHIND THE SECOND FRONT...WINDS WILL SHIFT TO THE NORTHEAST AND COULD GUST FOR A COUPLE HOURS TO 20 OR 25 MPH. TEMPS WILL ALSO COOL OFF QUICKLY BEHIND THE FRONT WITH LOWS FALLING INTO THE MIDDLE 30S NORTH TO THE MIDDLE 40S SOUTH. SATURDAY...CANADIAN HIGH PRESSURE WILL BUILD SOUTHEAST ACROSS THE CENTRAL GREAT LAKES. THE AIRMASS ASSOCIATED WITH THIS SURFACE HIGH IS EXCEPTIONALLY DRY (NAM 850-700MB RH FALLS TO 2 PCT!). THOUGH HIGH CLOUDS WILL BE ON THE INCREASE DURING THE AFTERNOON AHEAD OF THE CENTRAL ROCKIES UPPER LOW...SHOULD STILL SEE PLENTY OF SUNSHINE ALBEIT WITH COOLER TEMPERATURES. CRITICAL RELATIVE HUMIDITIES BETWEEN 15 TO 25 PCT WILL STILL OCCUR THOUGH NORTH AND WEST OF THE FOX VALLEY. POTENTIAL IS THERE FOR HUMIDITIES TO FALL LOWER THAN THIS IF TAPPING OCCURS INTO THIS BONE DRY AIR ALOFT. HIGHS MAINLY IN THE LOW TO MID 60S AWAY FROM LAKE MICHIGAN. .LONG TERM...SATURDAY NIGHT THROUGH THURSDAY ISSUED AT 400 AM CDT FRI APR 17 2015 500MB OPEN TROUGH WILL EVOLVE INTO A CLOSED LOW OVER THE WESTERN GREAT LAKES REGION BY EARLY NEXT WEEK. COOL CYCLONIC FLOW WILL CONTINUE FOR THE REMAINDER OF NEXT WEEK AS THE 500MB LOW MEANDERS ACROSS THE GREAT LAKES REGION/EASTERN CANADA. MODELS IN SOMEWHAT BETTER AGREEMENT TONIGHT BRINGING THE BEST CHANCE FOR RAIN SUNDAY INTO SUNDAY NIGHT. WILL CONTINUE A SMALL CHANCE OF SHOWERS AFTER MIDNIGHT ON SATURDAY NIGHT TO ACCOUNT FOR A SLIGHTLY QUICKER ARRIVAL THAT SOME OF THE MODELS ARE DEPICTING. WILL HAVE LIKELY OR LOW END CATEGORICAL CHANCES FOR RAIN ON SUNDAY. HIGH TEMPERATURES TRICKY DEPENDING ON QUICK THE STEADIER RAINS ARRIVE. IF RAIN ARRIVES EARLY IN THE DAY SUNDAY...HIGH TEMPERATURES WILL NEED TO BE LOWERED. COUNTING ON SOME DRY ON BACKSIDE OF THE RETREATING HIGH PRESSURE SYSTEM TO SLOW THE ARRIVAL OF THE RAIN ACROSS EASTERN WISCONSIN. OTHERWISE...BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE WEEK WITH CHANCES OF RAIN INTO THE MIDDLE OF NEXT WEEK. STILL HAVE A CHANCE OF SNOW LATE AT NIGHT OR EARLY IN THE DAY FOR EACH PERIOD FROM MONDAY NIGHT THROUGH WEDNESDAY. BY THURSDAY...UPPER LOW MAY BE FAR ENOUGH AWAY FOR JUST A SMALL CHANCE OF RAIN ACROSS THE FAR NORTH. PREVIOUS FORECAST TEMPERATURES SEEMED REASONABLE WITH ONLY MINOR CHANGES MADE IN SOME PERIODS. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1048 PM CDT THU APR 16 2015 VFR CONDITIONS EXPECTED TONIGHT INTO FRIDAY. A FRONTAL BOUNDARY WILL DROP SOUTHEASTWARD OVER THE STATE TONIGHT INTO FRIDAY MORNING. SINCE THE AIR MASS IS DRY...EXPECT A BAND OF MID LEVEL CLOUDS TO BE ASSOCIATED WITH THE FRONT. LIGHT SOUTHWEST WINDS SHIFTING NORTHWEST WILL MARK THE FRONTS PASSAGE. LATER FRIDAY MORNING...DEEP MIXING MAY PRODUCE A WEST WIND OF 5 TO 10 MPH WHILE WINDS TURN NORTHEAST TO EAST ALONG LAKE MICHIGAN FRIDAY AFTERNOON. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1053 PM MDT THU APR 16 2015 .UPDATE... ISSUED AT 539 PM MDT THU APR 16 2015 LATEST RADAR TRENDS SHOWING PRECIP FILLING IN OVER NORTEASTERN COLORADO. LATEST INFRARED IMAGERY SHOWING RAPIDLY COOLING CLOUD TOPS OVER SOUTHEASTERN COLORADO...MOVING DUE NORTH...SO OUR DRY SLOT WE HAVE BEEN LOOKING AT LATE THIS AFTERNOON IS GETTING EDGED EASTWARD. BOTH GFS AND NAM SOUNDINGS SHOWING FAVORABLE TEMPERATURE PROFILES LATE THIS EVENING WITH SURFACE TEMPERATURES FALLING TO BELOW FREEZING DURING THE BEST TIME OF LOW LEVEL MOISTURE CONVERGENCE OVER THE SOUTH LARAMIE RANGE. VERY STRONG ISENTROPIC LIFT OVER EXTREME SOUTHEAST WYOMING THIS EVENING FROM THE 300-310K PRESSURE SURFACES. OPTED TO UPGRADE THE CURRENT WINTERWEATHER ADVISORY WE HAVE GOING FOR CENTRAL LARAMIE COUNTY TO A WINTER STORM WARNING AS WELL AS INCREASING SNOW AMOUNTS ACROSS THE WARNED AREA AS ALL GUIDANCE POINTING TOWARDS OVER AN INCH OF STORM TOTAL QPF WITH THIS EVENT. UPDATES HAVE BEEN SENT. NEXT CONCERN DEALS WITH POSSIBILITY OF UPGRADING ADVISORIES FURTHER NORTH ACROSS THE CENTRAL LARAMIE RANGE AND POSSIBLY PLATTE COUNTY. CURRENT THINKING RIGHT NOW IS THE AXIS OF HEAVIEST PRECIP WILL MOVE INTO THIS AREA TOMORROW AFTERNOON DURING DAYLIGHT HOURS...SO MAYBE THERE WOULD BE A LITTLE MORE MELTING. DECIDED TO LET THE NIGHT CREW TAKE ANOTHER LOOK AT THIS BEFORE ISSUING ANYTHING. && .SHORT TERM...(TONIGHT-SATURDAY NIGHT) ISSUED AT 248 PM MDT THU APR 16 2015 FORECAST PROBLEMS WILL BE TEMPERATURES AND PRECIPITATION AMOUNTS AND WHERE THE HEAVIER SNOWS WILL FALL OVER THE NEXT COUPLE DAYS. UPPER LOW SPINNING OVER THE 4 CORNERS AREA SHOULD BEGIN A SLOW ENE DRIFT ACROSS COLORADO LATER TONIGHT BEFORE LIKELY STALLING AGAIN OVER COLORADO. PERIODIC DISTURBANCES ROTATING AROUND THIS LOW WILL BRING SHOTS OF RAIN AND SNOW TO MOST OF THE CWA THROUGH SATURDAY BEFORE A SHORTWAVE DROPS OUT OF SW CANADA AND PICKS UP THE LOW...MOVING IT EAST INTO KANSAS AND DECREASING PCPN ACROSS THE CWA. HIGHEST SNOWFALL WILL BE OVER THE LARAMIE RANGE AND THE SNOWYS. ONE CONCERN IS CONVECTION CURRENTLY FIRING OVER KANSAS WHICH COULD CUT MOISTURE AVAILABILITY IN THIS AREA AND REDUCE SNOWFALL AMOUNTS. CURRENT WINTER STORM WARNING LOOKS IN GOOD SHAPE REGARDLESS BUT FOR AREAS SUCH AS AROUND CHEYENNE SNOWFALL COULD TURN OUT GREATER THAN CURRENTLY ANTICIPATED...WITH THE GREATEST RISK BEING LATER TONIGHT INTO FRIDAY MORNING. WILL STAY WITH THE WINTER WX ADVY BUT IT WONT TAKE MUCH TO UPGRADE IT. TEMPERATURES TRICKY THROUGH FRIDAY ESPECIALLY ADJACENT TO THE LAR RANGE WHERE EXPECTED WARMING TODAY DID NOT OCCUR DUE TO SOME COLD AIR DAMMING. SFC WINDS LIKELY TO REMAIN NORTH TO NORTHEASTERLY THUS WAA WILL BE LIMITED IF AT ALL IN THIS AREA. THUS EXPECT PCPN TO REMAIN ALL SNOW THUS HAVE UPPED SNOWFALL AMOUNTS THERE. SHOULD SEE IMPROVEMENT FRIDAY AFTERNOON OVER THE HIGH PLAINS WITH THE NEXT EXPECTED LULL. PCPN SHOULD BECOME MORE SHOWERY IN NATURE FRIDAY NIGHT AND SATURDAY WITH SNOW LEVEL RISING SLOWLY AS SOME WARMING OCCURS. .LONG TERM...(SUNDAY-WEDNESDAY) ISSUED AT 248 PM MDT THU APR 16 2015 OUR PROBLEM CHILD UPPER-LOW WILL FINALLY LOOSEN ITS GRIP ON SUN AS A STRONG KICKER SYSTEM DIVES SOUTHEAST ACROSS THE DAKOTAS. THE PATTERN WILL REMAIN UNSETTLED THOUGH AS CYCLONIC MID LEVEL FLOW WILL REMAIN INTACT OVER THE NORTHERN/CENTRAL ROCKIES. EXPECT INSTABILITY SHOWERS TO CONTINUE FOR MOST OF THE CWA LATE IN THE WEEKEND. GFS/ECMWF SHOW H7 TEMPS FALLING TO AROUND -8 TO -10 DEG C ON SUN AM BEHIND A STRONG COLD FROPA...SO EXPECT THE PTYPE TO BE SNOW. THIS SHOULD NOT AMOUNT TO MUCH OUTSIDE OF THE MOUNTAINS THOUGH. MOST MEDIUM RANGE GUIDANCE SHOWS THE COOL/MOIST CYCLONIC FLOW PERSISTING THROUGH THE MIDDLE OF NEXT WEEK...SO EXPECT CONTINUED DAILY CHANCES FOR RAIN/SNOW SHOWERS WITH LITTLE OR NO ACCUMULATIONS. A WARMING TREND SHOULD BEGIN BY WED AS RIDGING FINALLY TRANSLATES EASTWARD...ALLOWING H7 TEMPS TO CLIMB BACK ABOVE FREEZING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1049 PM MDT THU APR 16 2015 HRRR GUIDANCE USED FOR THE 06Z TAFS. IFR.LIFR CONDITIONS INITIALLY CONFINED TO KLAR AND KCYS WITH WRAP AROUND MOISTURE AND SNOW. LATEST IR IMAGERY SHOWS COOLING CLOUD TOPS THAT INDICATES MOE WIDESPREAD PRECIP LATER THIS MORNING. HRRR SHOWS IFR/LIFR SPREADING EAST INTO THE SOUTHERN NEBRASKA PANHANDLE DURING THE 09-10Z TIMEFRAME AND CONTINUING THROUGH THE DAY FRIDAY. COULD PERSIST THROUGH FRIDAY NIGHT. && .FIRE WEATHER... ISSUED AT 248 PM MDT THU APR 16 2015 MINIMAL CONCERNS SEEN THROUGH THE WEEKEND WITH GENEROUS RAIN AN/OR SNOWS FALLING OVER MUCH OF THE AREA. TEMPERATURES WILL BE COOL TO MILD WITH WEATHER CONDITIONS NON-CRITICAL. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER STORM WARNING UNTIL NOON MDT FRIDAY FOR WYZ114>118. WINTER WEATHER ADVISORY UNTIL NOON MDT FRIDAY FOR WYZ103-105-106- 110-112. NE...NONE. && $$ UPDATE...GCC SHORT TERM...RE LONG TERM...CLH AVIATION...GCC FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
410 AM MDT FRI APR 17 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 410 AM MDT FRI APR 17 2015 THERE ARE SEVERAL CONCERNS FOR THE SHORT TERM FORECAST...INCLUDING THE POTENTIAL FOR CRITICAL FIRE WX CONDITIONS...THE POTENTIAL FOR SEVERE STORMS AND SNOW AMOUNTS. STILL SEE OCNL LIGHTNING STRIKES OVR SERN CO THIS MORNING. SATELLITE IMAGES SHOW THE UPR LOW CENTERED OVR NWRN NM THIS MORNING...AND IT IS FORECAST TO MOVE NORTHEASTWARD TODAY AND TONIGHT. BY 12Z SAT...THE NAM...GFS AND ECMWF SHOW THE LOW CENTER IN DIFFERENT LOCATIONS. THE GFS AND ECMWF ARE FAIRLY SIMILAR WITH THE LOW ABOUT OVR THE PALMER DVD...THE GFS IS A LITTLE FARTHER E AND S THAN THE ECMWF. THE NAM HAS THE LOW CENTER AT 12Z SAT OVR NRN SAGUACHE COUNTY. FOR THE FIRST HALF OF TODAY THE MODELS SHOW CONTINUED MOIST EASTERLY FLOW ACRS THE PIKES PEAK REGION...FREMONT COUNTY AND LAKE AND CHAFFEE COUNTIES...WITH SOME PCPN ALSO OVR THE SW MTNS AND SRN PORTIONS OF THE ERN MTNS...JUST NOT AS HEAVY AS NRN AREAS. AT THE SAME TIME...A DRY SLOT WL WORK ITS WAY INTO THE SERN PLAINS. HOWEVER...THE NAM HAS AN AREA OF CONVECTION DEVELOPING...MAINLY N OF HIGHWAY 50 OVR THE ERN PLAINS THIS AFTERNOON...WITH LAS ANIMAS AND BACA COUNTIES REMAINING DRY. THE GFS AND HRRR ARE DRY THIS AFTERNOON OVR THE FAR SERN PLAINS. STRONG SOUTHERLY WINDS OVR BACA AND LAS ANIMAS COUNTIES...ALONG WITH RH VALUES DROPPING BELOW 15 PERCENT ARE EXPECTED THIS AFTERNOON SO WL ISSUE A RED FLAG WARNING FOR THESE LOCATIONS. PORTIONS OF SRN PROWERS AND BENT COUNTIES MAY ALSO REACH RED FLAG CRITERIA...BUT UNCERTAINTY ABOUT PCPN OVR THESE COUNTIES WL KEEP ME FROM ISSUING A FIRE HIGHLIGHT AT THIS TIME. THE NAM DECREASES PCPN OVR MANY OF THE MTN AREAS THIS AFTERNOON...WHILE IT STILL LOOKS GOOD ON THE GFS OVR THE NRN MTNS PORTIONS OF THE CWA. THE ECMWF DECREASES PCPN OVR THE PIKES PEAK REGION BUT KEEPS GOOD PCPN GOING OVR LAKE AND CHAFFEE COUNTIES. THE GFS IS MUCH DRIER AT THE SFC THIS AFTERNOON OVR THE FAR SERN PLAINS THAN THE NAM...WHICH MAKES A DIFFERENCE IN THE POTENTIAL FOR SEVERE WX. WL LEAN THE FORECAST A LITTLE MORE TOWARD THE NAM OVR PROWERS...BENT...AND KIOWA COUNTIES. IF THE NAM IS CORRECT...CAPE VALUES COULD RANGE FROM ABOUT 600-1500 J/KG OVR PROWERS...NRN BENT AND KIOWA COUNTIES...WITH 0-6KM SHEAR VALUES OF 50-60 KTS...AND WE COULD SEE A COUPLE SEVERE STORMS. THE HRRR ALSO SETS UP A DRYLINE MAINLY NORTH OF HIGHWAY 50S THIS AFTERNOON OVR THE FAR SERN PLAINS. HOWEVER...IF THE DRIER GFS IS CORRECT THE BETTER MSTR AND SVR CHANCES WL BE EAST OF THE AREA. TONIGHT AS THE UPR LOW CONTINUES TO LIFT NORTHEASTWARD...MUCH OF THE SERN PLAINS LOOK TO BE DRY...WITH MANY OF THE MTN AREAS STILL SEEING SOME PCPN. ALTHOUGH THE DIFFERING POSITIONS OF THE UPR LOW CENTER RESULT IN DIFFERENCES IN WHAT MTNS AREAS WL HAVE THE BEST PCPN CHANCES. WILL NOT MAKE ANY CHANGES TO THE WINTER WEATHER HIGHLIGHTS THIS MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 410 AM MDT FRI APR 17 2015 SATURDAY-SUNDAY...LATEST MODELS REMAIN IN DECENT AGREEMENT OF STRONG UPPER LOW ACROSS SOUTH CENTRAL COLORADO EARLY SATURDAY SLOWLY LIFTING NORTH AND EAST THROUGH SATURDAY NIGHT WITH THE SYSTEM THEN WEAKENING AND MERGING WITH A BROAD UPPER TROUGH TRANSLATING ACROSS THE NORTHERN TIER OF STATES. BEST CHANCES OF PRECIPITATION EARLY SATURDAY REMAINS ACROSS THE CONTDVD THROUGH THE SOUTHERN MTS WITH DEVELOPING WRAPAROUND PRECIPITATION SHIELD AND DEVELOPING NORTHWEST FLOW BEHIND THE PASSING SYSTEM. SHOULD SEE ISOLATED TO SCATTERED SHOWERS AND A FEW EMBEDDED THUNDERSTORMS ACROSS THE EASTERN PLAINS SATURDAY AFTERNOON AND EVENING WITH COLD CORE UPPER LOW TRANSLATING INTO NORTHEASTERN COLORADO. MAY NEED TO EXTEND OR ADD WINTER HIGHLIGHTS ACROSS THE CENTRAL MTS INTO SATURDAY WITH SEVERAL INCHES OF SNOW EXPECTED...ESPECIALLY AOA 10KT FEET. MID LEVEL TEMPS SLOWLY WARM SATURDAY AS THE SYSTEM LIFTS OUT ACROSS THE AREA AND SHOULD SEE HIGHS SLIGHTLY WARMER AS A RESULT...THOUGH STILL BELOW SEASONAL AVERAGES. PASSING UPPER SYSTEM ACROSS THE AREA LATE SATURDAY SENDS A COLD FRONT ACROSS THE EASTERN PLAINS EARLY SUNDAY MORNING...WITH GUSTY NORTH TO NORTHWEST WINDS OF 20 TO 40 MPH EXPECTED IN ITS WAKE...WITH THE STRONGEST WINDS EXPECTED ACROSS THE FAR EASTERN PLAINS. A MINOR WAVE EMBEDDED WITHIN THE NORTHWEST FLOW ALOFT SUPPORTS ISOLATED TO SCATTERED SHOWERS ACROSS THE AREA ON SUNDAY...WITH TEMPERATURES SLIGHTLY COOLER THAN SATURDAY. MONDAY-TUESDAY...EMBEDDED DISTURBANCES IN THE SLOWLY MODERATING NORTHWEST FLOW ACROSS THE AREA WILL KEEP ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS IN THE FORECAST WITH TEMPERATURES WARMING BACK TO NEAR SEASONAL AVERAGES. WEDNESDAY-THURSDAY...A REX LIKE BLOCKING PATTERN LOOKS TO SET UP ACROSS THE REGION WITH RIDGING ACROSS THE ROCKIES AND TROUGHS SETTING UP OVER THE COASTS. THIS LOOKS TO KEEP UNSETTLED WEATHER ACROSS THE AREA WITH COOL HIGH PRESSURE ACROSS THE MIDWEST KEEPING UPSLOPE FLOW IN PLACE ACROSS EASTERN COLORADO ALONG WITH INCREASING MOISTURE WITHIN DEVELOPING SOUTHWEST FLOW ALOFT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 410 AM MDT FRI APR 17 2015 KCOS WL MAINLY HAVE MVFR CONDITIONS THIS MORNING WITH THE POTENTIAL FOR SNOW SHOWERS OR A MIX OF RAIN AND SNOW. THIS AFTERNOON FORECAST SOUNDINGS SHOW A RETURN TO VFR CONDITIONS THROUGH EARLY EVENING...AND THEN THE POTENTIAL FOR MVFR CONDITIONS DEVELOPING AGAIN. KPUB SHOULD GENERALLY HAVE MVFR CONDITIONS WITH THE POTENTIAL FOR RAIN SHOWERS AND MAYBE EVEN A THUNDERSTORM. FORECAST SOUNDINGS SHOW A RETURN TO VFR CONDITIONS IN THE LATE MORNING HOURS AND THROUGH THE REST OF THE PERIOD. KALS SHOULD GENERALLY SEE VFR CONDITIONS UNTIL LATE TONIGHT...WHEN THERE WILL BE THE POTENTIAL FOR MVFR OR IFR CONDITIONS. BREEZY SOUTHWEST WINDS ARE EXPECTED THIS AFTERNOON. && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ059-062- 063-074-075. WINTER WEATHER ADVISORY UNTIL 6 PM MDT THIS EVENING FOR COZ077>079-084. RED FLAG WARNING FROM NOON TODAY TO 8 PM MDT THIS EVENING FOR COZ233-237. WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058-060-061- 072-073-080-082. WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ076-081. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ066. && $$ SHORT TERM...28 LONG TERM...MW AVIATION...28
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
637 AM EDT FRI APR 17 2015 .SYNOPSIS... A LOW-LEVEL WEDGE WILL REMAIN IN PLACE THROUGH EARLY TODAY AND BEGIN GRADUALLY DISSIPATING THIS AFTERNOON. AN UPPER DISTURBANCE WILL CONTRIBUTE TO SOME SHOWER ACTIVITY TODAY. AN UPPER RIDGE WILL PROVIDE FAIR WEATHER SATURDAY. EXPECT INCREASING MOISTURE AND PRECIPITATION CHANCES WITH SHOWERS AND POSSIBLY THUNDERSTORMS SUNDAY AND SUNDAY NIGHT. HEAVY RAIN MAY OCCUR. THE BULK OF THE MOISTURE WILL SHIFT TO OUR EAST MONDAY AHEAD OF A WEAK COLD FRONT THAT IS EXPECTED TO MOVE THROUGH THE AREA MONDAY AFTERNOON. FAIR WEATHER IF FORECAST BEHIND THE FRONT LATE MONDAY THROUGH WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... THE MODELS INDICATE DIMINISHED ISENTROPIC LIFT TODAY WITH THE WEDGE PATTERN DISSIPATING BY THE MIDDLE OF THE DAY. THERE WILL BE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH. THE MODELS SHOW THE GREATER FORCING ASSOCIATED WITH THE UPPER FEATURE AFFECTING THE SOUTH PART TODAY. THE MODELS HAVE TRENDED WITH INCREASING POPS. THE ARW AND SPC WRF DISPLAY SCATTERED COVERAGE OF SHOWERS. THE HRRR IS TRENDING WITH GREATER COVERAGE APPROACHING THE CSRA BY EARLY AFTERNOON. INSTABILITY ASSOCIATED WITH THE MID-LEVEL SHORTWAVE TROUGH PLUS THE BREAK DOWN OF THE SURFACE WEDGE PATTERN SUGGESTS POSSIBLE THUNDERSTORMS THIS AFTERNOON. BELIEVE CLOUDINESS WILL HELP KEEP INSTABILITY WEAK. THE MODELS ALSO INDICATE WEAK SHEAR. BELIEVE ANY THUNDERSTORMS THIS AFTERNOON WILL BE ISOLATED. THERE IS LOW CONFIDENCE WITH THE HIGH TEMPERATURE FORECAST TODAY BECAUSE OF TIMING UNCERTAINTY WITH THE DISSIPATING WEDGE PATTERN. THE MODELS TYPICALLY DIMINISH THE WEDGE TOO QUICKLY SUPPORTING THE COOLER GUIDANCE. THE MODELS DISPLAYED LINGERING HIGH LOW-LEVEL MOISTURE TONIGHT. THE GFS HAD MORE MID-LEVEL SHORTWAVE TROUGHING AFFECTING MAINLY THE SOUTH PART OF THE FORECAST AREA TONIGHT. THE GUIDANCE CONSENSUS SUPPORTED CHANCE POPS MAINLY IN THE SOUTH PART. THERE MAY BE AREAS OF FOG BECAUSE OF THE HIGH LOW-LEVEL MOISTURE WITH LIGHT WIND PLUS THE NAM FORECAST OF MID-LEVEL DRYING. THE GUIDANCE TEMPERATURES WERE CLOSE. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... LATEST MODEL RUNS TRENDING SLOWER WITH PROGRESSION OF SYSTEMS AFFECTING OUR REGION. UPPER LOW WILL CONTINUE TO MEANDER OVER THE W CONUS...FOUR CORNERS/FRONT RANGE REGION...THROUGH SATURDAY WITH THE MAIN UPPER FLOW REMAINING WELL TO OUR NORTH ACROSS CANADA. LATEST MODEL RUNS INDICATE UPPER SHORT WAVE TO TRAVERSE OUR REGION FRIDAY...WITH UPPER RIDGE AXIS NOT SHIFTING EAST INTO OUR REGION UNTIL SATURDAY. LOW LEVEL WEDGE WILL TRY TO GRADUALLY ERODE FRIDAY. MODELS INDICATE WEDGE ERODING DURING THE MORNING...BUT MODELS TEND TO ERODE WEDGES TOO QUICKLY. HOWEVER...WEDGE MAY INDEED ERODE DURING THE AFTERNOON. WITH UPPER SHORT WAVE...DIURNAL HEATING...AND APPEARANCE OF SUFFICIENT ATMOSPHERIC MOISTURE OVER THE REGION...BUMPED UP POPS FOR FRIDAY. SATURDAY NOW APPEARS WILL BE GENERALLY FAIR...WITH UPPER RIDGE AXIS AND DRIER MID LEVEL AIR OVER THE REGION...THOUGH DIURNAL HEATING AND SEA BREEZE COULD LEAD TO SOME AFTERNOON SHOWERS AND A POSSIBLE THUNDERSTORM MAINLY SOUTH. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... FRONT RANGE UPPER LOW IS PROGGED TO GRADUALLY OPEN AND SHIFT EAST INTO THE CENTRAL CONUS SAT NT AND SUN IN RESPONSE TO NORTHERN STREAM UPPER ENERGY DIGGING SE FROM W CANADA/PAC NW INTO THE NORTHERN ROCKIES/N PLAINS. UPPER HIGH AXIS WILL SHIFT TO OUR EAST OFFSHORE SAT NT. AHEAD OF THE UPPER LOW...SOUTHERN STREAM UPPER IMPULSES WILL MOVE NE FROM NORTHERN MEXICO INTO THE LOWER MISSISSIPPI VALLEY/GULF COAST REGION. THIS WILL LEAD TO SURFACE LOW DEVELOPING OVER THE LOWER MISSISSIPPI VALLEY AND TRACKING NE INTO THE MIDWEST/GREAT LAKES REGION...WHILE SURFACE HIGH SHIFTS SE INTO NEW ENGLAND. AN INCREASING SE LOW LEVEL FLOW SATURDAY...BECOMING SW SUNDAY...WILL BRING INCREASING MOISTURE BACK INTO OUR REGION. WITH MODELS SLOWING PROGRESSIONS OF SYSTEMS DOWN SOME...IT NOW APPEARS AXIS OF HIGH MOISTURE AND ASSOCIATED SHOWERS AND POSSIBLE THUNDERSTORMS WILL PROVIDE THE BEST THREAT OF PRECIPITATION AND POSSIBLY HEAVY RAIN...SUNDAY AFTERNOON THRU SUN NT TIME FRAME. THERE ARE INDICATIONS THAT WITH MUCH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES FOR THIS TIME OF YEAR...THAT HEAVY RAIN WILL BE POSSIBLE. MODELS SHIFT THE AXIS OF HIGHEST MOISTURE TO OUR EAST BY MONDAY AHEAD OF A COLD FRONT PASSING THROUGH MONDAY AFTERNOON. HOWEVER...SOME SHOWER AND POSSIBLE THUNDERSTORM ACTIVITY WILL BE POSSIBLE WITH THE FROPA. DRIER AIR AND HIGH PRESSURE BEHIND THE FRONT APPEARS WILL PROVIDE FAIR WEATHER FOR OUR REGION MONDAY NIGHT THROUGH MID WEEK. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... COOL WEDGE REMAINS IN PLACE WITH MAINLY DRIZZLE OVER THE AREA EARLY THIS MORNING. IFR CIGS START THE FORECAST. MOST OF THE GFS AND NAM MOS PLUS SREF GUIDANCE SHOW AN IMPROVING TREND INTO THE MVFR CATEGORY THIS AFTERNOON. THE NAM SURFACE-BASED LI PATTERN SUGGESTED THE WEDGE PATTERN WILL DISSIPATE BY THE MIDDLE OF THE DAY. CONFIDENCE IS NOT HIGH WITH THE TIMING. THE MODELS TYPICALLY DIMINISH WEDGES TOO QUICKLY. THERE WILL BE LIFT ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH TODAY. THE MODELS INDICATED FORCING ASSOCIATED WITH THE UPPER FEATURE WILL BE STRONGER IN THE SOUTH. SHOWERS AND ASSOCIATED RESTRICTIONS MAY BE MORE WIDESPREAD AT AGS AND DNL AND WE FORECASTED MORE PESSIMISTIC CONDITIONS AT THESE TERMINALS THAN FARTHER NORTH. THE SPC WRF AND ARW MODELS DISPLAY SCATTERED SHOWER COVERAGE. THE HRRR IS TRENDING WITH GREATER COVERAGE APPROACHING THE CSRA BY EARLY AFTERNOON. INSTABILITY ASSOCIATED WITH THE MID-LEVEL SHORTWAVE TROUGH PLUS THE BREAK DOWN OF THE SURFACE WEDGE PATTERN SUGGESTS POSSIBLE THUNDERSTORMS THIS AFTERNOON. BELIEVE CLOUDINESS WILL HELP KEEP INSTABILITY WEAK. BELIEVE ANY THUNDERSTORMS THIS AFTERNOON WILL BE ISOLATED WITH THE CHANCE TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. THE MODELS DISPLAYED LINGERING HIGH LOW-LEVEL MOISTURE TONIGHT. THE GFS HAD MORE MID-LEVEL SHORTWAVE TROUGHING AFFECTING MAINLY THE SOUTH PART OF THE FORECAST AREA TONIGHT SUPPORTING A CONTINUED SHOWER CHANCE. THERE MAY BE AREAS OF FOG BECAUSE OF THE HIGH LOW- LEVEL MOISTURE WITH LIGHT WIND PLUS THE NAM FORECAST OF MID-LEVEL DRYING. EXTENDED AVIATION OUTLOOK...WIDESPREAD MVFR OR IFR CONDITIONS MAY OCCUR SATURDAY MORNING BECAUSE OF RESIDUAL LOW-LEVEL MOISTURE. A WARM FRONT WILL LIKELY BRING WIDESPREAD MVFR OR IFR CONDITIONS SATURDAY NIGHT THROUGH EARLY MONDAY MORNING. && .HYDROLOGY... RAINFALL ACROSS THE AREA THE PAST COUPLE OF DAYS COMBINED WITH RELEASES FROM PARR RESERVOIR AND LAKE MURRAY WILL PRODUCES RISES ALONG THE CONGAREE RIVER. THE RIVER IS FORECAST TO CREST JUST BELOW THE ADVISORY STAGE OF 10 FEET AT COLUMBIA TODAY. A CREST NEAR FLOOD STAGE OF 115 FEET AT CAROLINA EASTMAN MAY OCCUR TODAY. THIS WILL PRODUCE SOME MINOR FLOODING ALONG THE THREE RIVERS GREENWAY AND ALSO DOWNSTREAM FROM COLUMBIA OVER THE WEEKEND AT THE CONGAREE NATIONAL PARK. ALL OTHER FORECAST POINTS ACROSS THE MIDLANDS AND CSRA ARE EXPECTED TO REMAIN BELOW FLOOD STAGE THROUGH SATURDAY...BUT POSSIBLE HEAVY RAIN IN THE HEADWATERS SUNDAY COULD LEAD TO RIVER FLOODING. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1057 AM CDT FRI APR 17 2015 .UPDATE... ISSUED AT 1050 AM CDT FRI APR 17 2015 WEAK RIDGING OVER THE REGION KEEPING MILD WEATHER IN PLACE. QUICK MORNING WARM UP UNDER A MOSTLY SUNNY SKY AND TEMPS ON TRACK TO HEAD INTO THE UPPER 70S. ALTHOUGH CUMULUS CLOUDS ARE EXPECTED TO DEVELOP LATER THIS AFTERNOON...COVERAGE SHOULD BE LIGHTER IN THE NORTH THAN THE SOUTHERN TIER OF THE STATE...AND SHOULD NOT INTERFERE TOO MUCH WITH THE DIURNAL TREND UNDER SUCH LIGHT WINDS. FORECAST DOING WELL...HAVE ONLY MADE SOME MINOR ADJUSTMENTS. MAJOR UPDATES ARE NOT ANTICIPATED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 331 AM CDT FRI APR 17 2015 A DENSE FOG ADVISORY ISSUED AROUND 2 AM FOR EASTERN IL WILL BE ALLOWED TO CONTINUE THROUGH 9 AM CDT. THE PAST HOUR OR TWO THE DENSE FOG WITH VSBYS 1/4 MILE OR LESS HAS BEEN CONFINED TO AREAS EAST OF I- 57 AND COULD EXPAND FURTHER WEST OF I-57 WITH AREAS OF FOG AND PATCHY DENSE FOG AS FAR WEST AS I-55 PER HRRR MODEL UNTIL 9 AM. ONCE THE FOG LIFTS LATER THIS MORNING A NICE MILD SPRING DAY IS SHAPING UP ACROSS CENTRAL AND SOUTHEAST IL WITH WEAK HIGH PRESSURE OVER IN AND SOME UPPER LEVEL RIDGING INTO IL GIVING MOSTLY SUNNY SKIES AND LIGHT WINDS AND MILD HIGHS IN THE MID TO UPPER 70S. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 331 AM CDT FRI APR 17 2015 DRY CONDITIONS STILL EXPECTED TO CONTINUE ACROSS CENTRAL AND SOUTHEAST IL THROUGH AT LEAST SAT MORNING WITH JUST ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE DURING MID/LATE SAT AFTERNOON ALONG AND SW OF A GALESBURG TO LINCOLN TO LAWRENCEVILLE LINE. UPPER LEVEL RIDGE INTO THE OHIO RIVER VALLEY AND IL YET ON SATURDAY TO BRING ANOTHER MILD SPRING DAY IN THE MID TO UPPER 70S SATURDAY, WITH MILDEST READINGS NEAR THE IN BORDER WHERE MORE SUNSHINE EXPECTED. LARGE CUTOFF UPPER LEVEL LOW OVER COLORADO TONIGHT AND SATURDAY GETS ABSORBED BY NORTHERN STREAM CUTOFF LOW NORTH OF ND/MN SUNDAY AND MONDAY. WARM AIR ADVECTION SHOWERS AND SCATTERED THUNDERSTORMS TO SPREAD NE ACROSS CENTRAL AND SOUTHEAST IL DURING SATURDAY NIGHT ESPECIALLY AFTER MIDNIGHT AND CONTINUE SUNDAY. FAIRLY STRONG SURFACE LOW PRESSURE EJECTS NE FROM OK PANHANDLE TO NEAR CENTRAL IL BY SUNSET SUNDAY AND SWEEPS A COLD FRONT EAST THROUGH IL SUNDAY NIGHT. THIS TO LIKELY BRING MORE SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT AND SPC HAS MARGINAL RISK OF SEVERE STORMS SW OF I-74 SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING WITH SLIGHT RISK SW OF A PITTSFIELD TO EFFINGHAM TO LAWRENCEVILLE LINE FOR LARGE HAIL AND DAMAGING WIND GUSTS POSSIBLE. HIGHS SUNDAY MOSTLY IN THE LOWER 70S WITH SOME UPPER 60S NORTH OF I-74. A LARGE UPPER LEVEL TROF THEN DOMINATES THE MIDWEST MONDAY-THURSDAY AS STRONG CUTOFF LOW MOVES SLOWLY EAST ACROSS THE NORTHERN GREAT LAKES REGION. SHOWERS SHOULD DIMINISH TO WIDELY SCATTERED SHOWERS OVER CENTRAL IL ON MONDAY WITH BEST CHANCES OF SHOWERS OVER IN AND NORTHERN IL. COOLER HIGHS OF 60-65F MONDAY WITH MILDEST READINGS BY LAWRENCEVILLE. HAVE DRY AND COOL CONDITIONS MONDAY NIGHT THROUGH TUE NIGHT. THEN SMALL CHANCES OF SHOWERS WED/THU WITH A WEATHER SYSTEM APPROACHING FROM THE SW WITH GFS MODEL TRENDING MUCH WETTER DURING THIS TIME FRAME WHILE ECMWF MODEL IS KEEPING IL DRY. COOL HIGHS IN THE UPPER 50S/LOWER 60S TUE-WED WITH LOWS IN THE UPPER 30S TO MID 40S, WITH COOLEST READINGS FROM I-74 NORTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 639 AM CDT FRI APR 17 2015 DENSE FOG MOVED IN FROM THE EAST LAST NIGHT AND IS NOW COVERING CMI ONLY. DEC AND BMI HAVE SOME LIGHT FOG AND COULD SEE LOWER CONDITIONS FOR A COUPLE OF HOURS THIS MORNING. SO WILL HAVE TEMPO GROUP FOR CMI, DEC, AND BMI. SPI AND PIA SHOULD NOT SEE ANY FOG, GIVEN THE TEMP/DEWPOINT SPREAD, ESPECIALLY AT PIA. BESIDES THE FOG, HIGH CIRRUS WILL SPREAD OVER ALL TAF SITES THIS MORNING AND WILL CONTINUE THROUGH THE AFTERNOON AND INTO TONIGHT. MORE FOG IS POSSIBLE AGAIN TONIGHT, SO HAVE ADDED 3-4SM AT ALL SITES AROUND MIDNIGHT. WINDS SHOULD BE LIGHT AND VARIABLE THROUGH THE PERIOD AS HIGH PRESSURE WILL DOMINATE THE AREA NEXT 24HRS. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HJS SHORT TERM...07 LONG TERM...07 AVIATION...AUTEN
AREA FORECAST DISCUSSION
NWS LINCOLN IL
639 AM CDT FRI APR 17 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 331 AM CDT FRI APR 17 2015 A DENSE FOG ADVISORY ISSUED AROUND 2 AM FOR EASTERN IL WILL BE ALLOWED TO CONTINUE THROUGH 9 AM CDT. THE PAST HOUR OR TWO THE DENSE FOG WITH VSBYS 1/4 MILE OR LESS HAS BEEN CONFINED TO AREAS EAST OF I- 57 AND COULD EXPAND FURTHER WEST OF I-57 WITH AREAS OF FOG AND PATCHY DENSE FOG AS FAR WEST AS I-55 PER HRRR MODEL UNTIL 9 AM. ONCE THE FOG LIFTS LATER THIS MORNING A NICE MILD SPRING DAY IS SHAPING UP ACROSS CENTRAL AND SOUTHEAST IL WITH WEAK HIGH PRESSURE OVER IN AND SOME UPPER LEVEL RIDGING INTO IL GIVING MOSTLY SUNNY SKIES AND LIGHT WINDS AND MILD HIGHS IN THE MID TO UPPER 70S. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 331 AM CDT FRI APR 17 2015 DRY CONDITIONS STILL EXPECTED TO CONTINUE ACROSS CENTRAL AND SOUTHEAST IL THROUGH AT LEAST SAT MORNING WITH JUST ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE DURING MID/LATE SAT AFTERNOON ALONG AND SW OF A GALESBURG TO LINCOLN TO LAWRENCEVILLE LINE. UPPER LEVEL RIDGE INTO THE OHIO RIVER VALLEY AND IL YET ON SATURDAY TO BRING ANOTHER MILD SPRING DAY IN THE MID TO UPPER 70S SATURDAY, WITH MILDEST READINGS NEAR THE IN BORDER WHERE MORE SUNSHINE EXPECTED. LARGE CUTOFF UPPER LEVEL LOW OVER COLORADO TONIGHT AND SATURDAY GETS ABSORBED BY NORTHERN STREAM CUTOFF LOW NORTH OF ND/MN SUNDAY AND MONDAY. WARM AIR ADVECTION SHOWERS AND SCATTERED THUNDERSTORMS TO SPREAD NE ACROSS CENTRAL AND SOUTHEAST IL DURING SATURDAY NIGHT ESPECIALLY AFTER MIDNIGHT AND CONTINUE SUNDAY. FAIRLY STRONG SURFACE LOW PRESSURE EJECTS NE FROM OK PANHANDLE TO NEAR CENTRAL IL BY SUNSET SUNDAY AND SWEEPS A COLD FRONT EAST THROUGH IL SUNDAY NIGHT. THIS TO LIKELY BRING MORE SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT AND SPC HAS MARGINAL RISK OF SEVERE STORMS SW OF I-74 SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING WITH SLIGHT RISK SW OF A PITTSFIELD TO EFFINGHAM TO LAWRENCEVILLE LINE FOR LARGE HAIL AND DAMAGING WIND GUSTS POSSIBLE. HIGHS SUNDAY MOSTLY IN THE LOWER 70S WITH SOME UPPER 60S NORTH OF I-74. A LARGE UPPER LEVEL TROF THEN DOMINATES THE MIDWEST MONDAY-THURSDAY AS STRONG CUTOFF LOW MOVES SLOWLY EAST ACROSS THE NORTHERN GREAT LAKES REGION. SHOWERS SHOULD DIMINISH TO WIDELY SCATTERED SHOWERS OVER CENTRAL IL ON MONDAY WITH BEST CHANCES OF SHOWERS OVER IN AND NORTHERN IL. COOLER HIGHS OF 60-65F MONDAY WITH MILDEST READINGS BY LAWRENCEVILLE. HAVE DRY AND COOL CONDITIONS MONDAY NIGHT THROUGH TUE NIGHT. THEN SMALL CHANCES OF SHOWERS WED/THU WITH A WEATHER SYSTEM APPROACHING FROM THE SW WITH GFS MODEL TRENDING MUCH WETTER DURING THIS TIME FRAME WHILE ECMWF MODEL IS KEEPING IL DRY. COOL HIGHS IN THE UPPER 50S/LOWER 60S TUE-WED WITH LOWS IN THE UPPER 30S TO MID 40S, WITH COOLEST READINGS FROM I-74 NORTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 639 AM CDT FRI APR 17 2015 DENSE FOG MOVED IN FROM THE EAST LAST NIGHT AND IS NOW COVERING CMI ONLY. DEC AND BMI HAVE SOME LIGHT FOG AND COULD SEE LOWER CONDITIONS FOR A COUPLE OF HOURS THIS MORNING. SO WILL HAVE TEMPO GROUP FOR CMI, DEC, AND BMI. SPI AND PIA SHOULD NOT SEE ANY FOG, GIVEN THE TEMP/DEWPOINT SPREAD, ESPECIALLY AT PIA. BESIDES THE FOG, HIGH CIRRUS WILL SPREAD OVER ALL TAF SITES THIS MORNING AND WILL CONTINUE THROUGH THE AFTERNOON AND INTO TONIGHT. MORE FOG IS POSSIBLE AGAIN TONIGHT, SO HAVE ADDED 3-4SM AT ALL SITES AROUND MIDNIGHT. WINDS SHOULD BE LIGHT AND VARIABLE THROUGH THE PERIOD AS HIGH PRESSURE WILL DOMINATE THE AREA NEXT 24HRS. && .ILX WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR ILZ044>046- 054>057-061>063-066>068-071>073. && $$ SHORT TERM...07 LONG TERM...07 AVIATION...AUTEN
AREA FORECAST DISCUSSION
NWS JACKSON KY
1058 AM EDT FRI APR 17 2015 .UPDATE... ISSUED AT 1058 AM EDT FRI APR 17 2015 WV IMAGERY INDICATES THAT THE WEAK TROUGH HAS PUSHED EAST OF THE AREA SO HAVE TRENDED POPS DOWN OVER THE NEXT 3 TO 6 HOURS...STILL KEPT A SLIGHT CHANCE IN OUR SOUTHEASTERN COUNTIES TO REMAIN WITHIN TOLERANCE WITH OUR NEIGHBORS DURING THAT TIME. OTHERWISE...IT/S JUST A CLOUD COVER AND TEMPERATURE FORECAST TODAY. SO HAVE UPDATED T AND TD GRIDS TO ALIGN WITH MOST RECENT OBS. NO OTHER CHANGES WERE MADE TO THE CURRENT FORECAST BUT WILL KEEP AN EYE ON CLOUD COVER AND TEMPS INTO THE AFTERNOON. SENT UPDATED GRIDS TO NDFD AND WEB SERVERS. UPDATE ISSUED AT 809 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME LOW LEVEL CLOUDS JUST TO THE WEST ASSOCIATED WITH A WEAK TROUGH MOVING THROUGH. THIS HAS ALSO SPAWNED A FEW SHOWERS ACROSS THE AREA. RECENT RADAR RETURNS HINT AT SOME OF THE ACTIVITY MAYBE DEVELOPING FURTHER SOUTH SO HAVE LEFT POPS IN THROUGH MIDDAY. AS WELL HAVE PUT FOG IN THE FORECAST LATE TONIGHT. WITH HIGH PRESSURE MOVING INTO THE AREA AND CLEARING SKIES LATER TODAY...AS WELL A MOIST SURFACE LAYER AND LIGHT WINDS WILL BE A FAVORABLE ENVIRONMENT FOR FOG DEVELOPMENT. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME MOIST SOUTHERLY FLOW MOVING INTO KENTUCKY FROM THE SOUTHWEST THIS MORNING. AT THIS TIME...WEAK SURFACE HIGH PRESSURE CENTERED OVER MI IS POISED TO SLOWLY CREEP SOUTHEAST. IN THIS AREA OVER THE LOWER GREAT LAKES...A BIT OF CLEARING MAY MAKE IT INTO EAST KENTUCKY THIS MORNING. THIS COMBINED WITH THE MOISTURE PRESENT OVER THE AREA MAY RESULT IN SOME DENSE FOG DEVELOPMENT TOWARDS DAWN. AT THIS POINT...IT LOOKS LIKE A TOUGH CALL WITH CLOUD COVER CONTINUING TO STREAM IN FROM THE SOUTHWEST. HAVE PUT PATCHY FOG IN THE FORECAST TO COVER THIS BUT WILL ALSO MONITOR FOG DEVELOPMENT TOWARDS DAWN. IN ADDITION TO THIS...A WEAK REMNANT TROUGH SLIDING EAST AHEAD OF HIGH PRESSURE MAY BE ENOUGH TO SPAWN A FEW SHOWERS. HI RES MODELS SUCH AS THE HRRR DO HINT AT THIS INTO THE DAY AS THIS TROUGH SLOWLY SLIDES THROUGH. WITH NO REAL SURFACE FEATURE THIS ACTIVITY IS TIED TO...WILL GO WITH SLIGHT CHANCE POPS THROUGH MIDDAY AND ONLY SHOWERS EXPECTED. HEADING INTO TONIGHT...MENTIONED HIGH PRESSURE WILL MOVE INTO THE AREA TONIGHT. SOME BREAKS IN THE CLOUD COVER IS EXPECTED...ESPECIALLY OVER THE NORTH WHERE SOME CLEAR SKIES LOOK TO DEVELOP. THIS MAY POSE AS A BETTER FOG SET UP AND MAY NEED TO MENTION THIS IN THE HWO. BY SATURDAY...A CLOSED UPPER LOW EJECTS INTO THE CENTRAL PLAINS...AND A SHORTWAVE MOVES OUT OF THE BASE OF THE LOW...CROSSING THE LOWER MS RIVER VALLEY AND NORTHEAST INTO THE OH AND TN VALLEYS. SURFACE LOW PRESSURE AND A DEVELOPING WARM FRONT WILL BRING A SURGE OF MOIST AIR INTO EAST KENTUCKY WITH A SLIGHT CHANCE POPS MAKING MAKING IT INTO POINTS SOUTH OF THE HAL ROGERS PARKWAY BY SATURDAY AFTERNOON. MODELS WITH THIS FEATURE HAVE BEEN PRETTY CONSISTENT AND THE BEST CHANCE OF MEASURABLE PRECIP WILL BE AFTER 00Z SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 335 AM EDT FRI APR 17 2015 CLOSED UPPER LEVEL LOW THAT HAS BEEN QUASI STATIONARY ACROSS THE DESERT SW WILL FINALLY BEGIN PHASING WITH A NORTHERN STREAM TROUGH AS WE MOVE INTO THE LONG RANGE PERIOD. DIFFLUENCE ALOFT...JET ENERGY... AND SHORTWAVE WILL AID IN DEVELOPING SURFACE LOW PRESSURE ACROSS THE SOUTHERN MISSISSIPPI RIVER VALLEY SATURDAY NIGHT. THIS WILL HELP TO SPREAD SHOWERS AND THUNDERSTORMS ACROSS THE REGION AS WE MOVE THROUGH THE DAY ON SUNDAY. MODEL SOUNDINGS WOULD SUGGEST PWATS BETWEEN 1.2 AND 1.4 INCHES DURING THIS PERIOD AS COLUMN SATURATES...THEREFORE SOME OF THESE SHOWERS AND STORMS WILL LIKELY BE MODERATE INTENSITY AT TIMES. GIVEN THE VERY WET ANTECEDENT CONDITIONS WE COULD SEE ISOLATED FLOODING THREAT ONCE AGAIN. THIS WILL DEPEND ON THE DEVELOPMENT AND MOVEMENT OF THE LOW PRESSURE THAT DEVELOPS AND MOVES NORTH NORTHEAST SUNDAY AND ALSO ANY CONVECTION THAT DEVELOPS. THIS UPPER LEVEL SYSTEM DOES LOOK TO PHASE WITH THE NORTHERN STREAM TROUGH AS MENTIONED ABOVE AND A CLOSED UPPER LEVEL LOW DEVELOPS ACROSS THE NORTHERN PLAINS. THIS WILL MAKE FOR A TWO PART SYSTEM AS ANOTHER SURFACE LOW DEVELOPS ACROSS THE UPPER MIDWEST SUNDAY EVENING ASSOCIATED WITH A SPOKE OF ENERGY FROM THE CLOSED UPPER LEVEL LOW. THIS LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION MONDAY AND RESULT IN ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. UP TO THIS POINT WE DO SEE GOOD MODEL AGREEMENT IN REGARDS TO THIS SYSTEM. PASSAGE OF THIS FRONT WILL BREAKDOWN THE PATTERN WITH MORE OF A WESTERLY FLOW AND COOLER AIR USHERED IN BEHIND THE FRONT. AN AREA OF HIGH PRESSURE WILL BUILD TO THE SOUTH WITH HIGHS TEMPS IN THE LOW TO MID 60S AND LOWS IN THE UPPER TO EVEN LOWER 40S TUESDAY INTO WEDNESDAY. MORE DIVERGENCE IN THE MODEL GUIDANCE EXISTS IN THE WEDNESDAY TO THURSDAY TIME FRAME. RIGHT NOW THE GFS AND GFS ENSEMBLE MEAN ARE WETTER THAN THE ECMWF AT THIS POINT. GIVEN THE UNCERTAINTY THAT EXISTS WILL LEAN TOWARD THE MODEL BLEND. THIS WILL BRING SLIGHT POPS ACROSS THE NORTH WEDNESDAY AFTERNOON AND CHANCE TO SLIGHT POPS WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 809 AM EDT FRI APR 17 2015 SOME LOW LEVEL CLOUD COVER ASSOCIATED WITH A WEAK TROUGH MOVING THROUGH FROM THE NORTHWEST WILL BRING SOME 2 TO 3 KFT CEILINGS THROUGH THE AREA BETWEEN 12Z AND 15Z THIS MORNING. AFTERWARD...SKIES WILL BEGIN TO CLEAR OUT BY THE AFTERNOON AND EVENING. HIGH PRESSURE MOVING IN LATER THIS EVENING AND TONIGHT ALONG WITH LIGHT WINDS WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR FOG DEVELOPMENT AND SO HAVE PUT IFR VIS IN ALL THE TAF SITES TONIGHT AFTER 06Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JVM SHORT TERM...SHALLENBERGER LONG TERM...DJ AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS JACKSON KY
810 AM EDT FRI APR 17 2015 .UPDATE... ISSUED AT 809 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME LOW LEVEL CLOUDS JUST TO THE WEST ASSOCIATED WITH A WEAK TROUGH MOVING THROUGH. THIS HAS ALSO SPAWNED A FEW SHOWERS ACROSS THE AREA. RECENT RADAR RETURNS HINT AT SOME OF THE ACTIVITY MAYBE DEVELOPING FURTHER SOUTH SO HAVE LEFT POPS IN THROUGH MIDDAY. AS WELL HAVE PUT FOG IN THE FORECAST LATE TONIGHT. WITH HIGH PRESSURE MOVING INTO THE AREA AND CLEARING SKIES LATER TODAY...AS WELL A MOIST SURFACE LAYER AND LIGHT WINDS WILL BE A FAVORABLE ENVIRONMENT FOR FOG DEVELOPMENT. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME MOIST SOUTHERLY FLOW MOVING INTO KENTUCKY FROM THE SOUTHWEST THIS MORNING. AT THIS TIME...WEAK SURFACE HIGH PRESSURE CENTERED OVER MI IS POISED TO SLOWLY CREEP SOUTHEAST. IN THIS AREA OVER THE LOWER GREAT LAKES...A BIT OF CLEARING MAY MAKE IT INTO EAST KENTUCKY THIS MORNING. THIS COMBINED WITH THE MOISTURE PRESENT OVER THE AREA MAY RESULT IN SOME DENSE FOG DEVELOPMENT TOWARDS DAWN. AT THIS POINT...IT LOOKS LIKE A TOUGH CALL WITH CLOUD COVER CONTINUING TO STREAM IN FROM THE SOUTHWEST. HAVE PUT PATCHY FOG IN THE FORECAST TO COVER THIS BUT WILL ALSO MONITOR FOG DEVELOPMENT TOWARDS DAWN. IN ADDITION TO THIS...A WEAK REMNANT TROUGH SLIDING EAST AHEAD OF HIGH PRESSURE MAY BE ENOUGH TO SPAWN A FEW SHOWERS. HI RES MODELS SUCH AS THE HRRR DO HINT AT THIS INTO THE DAY AS THIS TROUGH SLOWLY SLIDES THROUGH. WITH NO REAL SURFACE FEATURE THIS ACTIVITY IS TIED TO...WILL GO WITH SLIGHT CHANCE POPS THROUGH MIDDAY AND ONLY SHOWERS EXPECTED. HEADING INTO TONIGHT...MENTIONED HIGH PRESSURE WILL MOVE INTO THE AREA TONIGHT. SOME BREAKS IN THE CLOUD COVER IS EXPECTED...ESPECIALLY OVER THE NORTH WHERE SOME CLEAR SKIES LOOK TO DEVELOP. THIS MAY POSE AS A BETTER FOG SET UP AND MAY NEED TO MENTION THIS IN THE HWO. BY SATURDAY...A CLOSED UPPER LOW EJECTS INTO THE CENTRAL PLAINS...AND A SHORTWAVE MOVES OUT OF THE BASE OF THE LOW...CROSSING THE LOWER MS RIVER VALLEY AND NORTHEAST INTO THE OH AND TN VALLEYS. SURFACE LOW PRESSURE AND A DEVELOPING WARM FRONT WILL BRING A SURGE OF MOIST AIR INTO EAST KENTUCKY WITH A SLIGHT CHANCE POPS MAKING MAKING IT INTO POINTS SOUTH OF THE HAL ROGERS PARKWAY BY SATURDAY AFTERNOON. MODELS WITH THIS FEATURE HAVE BEEN PRETTY CONSISTENT AND THE BEST CHANCE OF MEASURABLE PRECIP WILL BE AFTER 00Z SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 335 AM EDT FRI APR 17 2015 CLOSED UPPER LEVEL LOW THAT HAS BEEN QUASI STATIONARY ACROSS THE DESERT SW WILL FINALLY BEGIN PHASING WITH A NORTHERN STREAM TROUGH AS WE MOVE INTO THE LONG RANGE PERIOD. DIFFLUENCE ALOFT...JET ENERGY... AND SHORTWAVE WILL AID IN DEVELOPING SURFACE LOW PRESSURE ACROSS THE SOUTHERN MISSISSIPPI RIVER VALLEY SATURDAY NIGHT. THIS WILL HELP TO SPREAD SHOWERS AND THUNDERSTORMS ACROSS THE REGION AS WE MOVE THROUGH THE DAY ON SUNDAY. MODEL SOUNDINGS WOULD SUGGEST PWATS BETWEEN 1.2 AND AOA 1.4 INCHES DURING THIS PERIOD AS COLUMN SATURATES...THEREFORE SOME OF THESE SHOWERS AND STORMS WILL LIKELY BE MODERATE INTENSITY AT TIMES. GIVEN THE VERY WET ANTECEDENT CONDITIONS WE COULD SEE ISOLATED FLOODING THREAT ONCE AGAIN. THIS WILL DEPEND ON THE DEVELOPMENT AND MOVEMENT OF THE LOW PRESSURE THAT DEVELOPS AND MOVES NORTH NORTHEAST SUNDAY AND ALSO ANY CONVECTION THAT DEVELOPS. THIS UPPER LEVEL SYSTEM DOES LOOK TO PHASE WITH THE NORTHERN STREAM TROUGH AS MENTIONED ABOVE AND A CLOSED UPPER LEVEL LOW DEVELOPS ACROSS THE NORTHERN PLAINS. THIS WILL MAKE FOR A TWO PART SYSTEM AS ANOTHER SURFACE LOW DEVELOPS ACROSS THE UPPER MIDWEST SUNDAY EVENING ASSOCIATED WITH A SPOKE OF ENERGY FROM THE CLOSED UPPER LEVEL LOW. THIS LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION MONDAY AND RESULT IN ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. UP TO THIS POINT WE DO SEE GOOD MODEL AGREEMENT IN REGARDS TO THIS SYSTEM. PASSAGE OF THIS FRONT WILL BREAKDOWN THE PATTERN WITH MORE OF A WESTERLY FLOW AND COOLER AIR USHERED IN BEHIND THE FRONT. AN AREA OF HIGH PRESSURE WILL BUILD TO THE SOUTH WITH HIGHS TEMPS IN THE LOW TO MID 60S AND LOWS IN THE UPPER TO EVEN LOWER 40S TUESDAY INTO WEDNESDAY. MORE DIVERGENCE IN THE MODEL GUIDANCE EXISTS IN THE WEDNESDAY TO THURSDAY TIME FRAME. RIGHT NOW THE GFS AND GFS ENSEMBLE MEAN ARE WETTER THAN THE ECMWF AT THIS POINT. GIVEN THE UNCERTAINTY THAT EXISTS WILL LEAN TOWARD THE MODEL BLEND. THIS WILL BRING SLIGHT POPS ACROSS THE NORTH WEDNESDAY AFTERNOON AND CHANCE TO SLIGHT POPS WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 809 AM EDT FRI APR 17 2015 SOME LOW LEVEL CLOUD COVER ASSOCIATED WITH A WEAK TROUGH MOVING THROUGH FROM THE NORTHWEST WILL BRING SOME 2 TO 3 KFT CEILINGS THROUGH THE AREA BETWEEN 12Z AND 15Z THIS MORNING. AFTERWARD...SKIES WILL BEGIN TO CLEAR OUT BY THE AFTERNOON AND EVENING. HIGH PRESSURE MOVING IN LATER THIS EVENING AND TONIGHT ALONG WITH LIGHT WINDS WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR FOG DEVELOPMENT AND SO HAVE PUT IFR VIS IN ALL THE TAF SITES TONIGHT AFTER 06Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SHALLENBERGER SHORT TERM...SHALLENBERGER LONG TERM...DJ AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1050 AM CDT FRI APR 17 2015 .DISCUSSION... AFTER A FUN DAY YESTERDAY...LOCAL 88DS ARE REFRESHINGLY QUIET THIS MORNING WITH MAINLY JUST RAINS ASSOCIATED WITH A DEPARTING DISTURBANCE ALOFT EXITING THE ERN COASTAL WATERS AND POSSIBLY BRUSHING LOWER ACADIANA. 12Z KLCH SOUNDING SHOWED A MUCH DRIER AIRMASS IN PLACE OVER THE REGION TODAY...WHILE THE MODIFIED SOUNDING SHOWED SIMILAR INSTABILITY TO THURSDAY. PLAYING TO OUR ADVANTAGE TODAY IS A RELATIVE LACK OF APPROACHING DISTURBANCES ROUNDING THE UPPER LOW OVER THE FOUR CORNERS REGION. HOWEVER GIVEN THAT WE ARE STILL REASONABLY MOIST AND FAIRLY UNSTABLE...DAYTIME HEATING OR PERHAPS SOME LINGERING BOUNDARIES FROM EARLIER CONVECTION COULD STILL SPARK SOME SHOWERS AND STORMS ESPECIALLY THIS AFTERNOON. DESPITE WHAT LOOKS LIKE A LACK OF PRECIP TODAY...STILL EXPECTING ANOTHER HEAVY RAINFALL EVENT BEGINNING TONIGHT AND RUNNING INTO SATURDAY. GIVEN THE FLOODING WHICH OCCURRED YESTERDAY AND THE SATURATED GROUNDS LEFT BEHIND FROM ALL THE RAIN...EXTENDED THE INHERITED FLASH FLOOD WATCH THROUGH LATE TOMORROW AFTERNOON. ELSEWHERE JUST TWEAKED GRIDS/ZONES BASED ON LATEST OBS/TRENDS... UPDATE ALREADY OUT. 25 && .PREV DISCUSSION... /ISSUED 616 AM CDT FRI APR 17 2015/ AVIATION...SINCE MIDNIGHT CONVECTIVE ACTIVITY HAS DECREASED SIGNIFICANTLY. RADAR NOW SHOWING JUST A FEW SHOWERS AND THUNDERSTORMS AND THESE OFFSHORE OVER THE NEAR COASTAL WATERS. TODAY LOOKS TO WITH MUCH LESS CONVECTION OVER THE AREA AS SOME SHARPLY DRIER MID LEVEL AIR ADVECTS INTO THE REGION. MODELS SUGGESTING A RAMPING UP OF PRECIP OVERNIGHT AS ANOTHER UPPER LEVEL DISTURBANCE APPROACHES. ALTOCU CLOUDS AT AROUND 10KT FT CURRENTLY OVER AREA. WILL SEE LOWER CLOUDS DEVELOP AS THE MORNING PROGRESSES BUT WILL MAINTAIN THESE WITHIN VFR. PREV DISCUSSION... /ISSUED 335 AM CDT FRI APR 17 2015/ DISCUSSION...POPS AND HEAVY RAIN WILL BE THE MAIN FORECAST ISSUES OVER THE NEXT 48 HOURS. WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY YESTERDAY AND OVERNIGHT WAS BEGINNING TO DECREASE AS OF 08Z. THE LATEST HRRR CONFIRMS THIS WITH ACTIVITY DECREASING SIGNIFICANT LATER THIS MORNING ESPECIALLY OVER EASTERN PARTS OF THE FORECAST AREA. WILL CONTINUE WITH FFA FOR NOW...BUT MAY CANCEL EARLY IF WEAKENING TREND CONTINUES. WILL TAPER POPS TO MID RANGE FOR THIS AFTERNOON. MODELS HAVE BEEN CONSISTENT IN LIFTING UPPER TROUGH NE THROUGH THE WEEKEND. ALSO...APPEARS THAT NEXT ROUND OF SHOWERS AND THUNDERSTORMS WILL BEGIN LATE TONIGHT AND BECOME MORE WIDESPREAD ON SATURDAY. WILL LIKELY NEED TO REISSUE FFA FOR TONIGHT AND SATURDAY. AFTER SATURDAY...A MUCH NEEDED PATTERN CHANGE IS FORECASTED. WEAK UPPER RIDGE SHOULD DEVELOP OVER THE GULF COAST STATES. A FRONTAL BOUNDARY SHOULD MOVE THROUGH THE AREA BY SUNDAY NIGHT AND THIS WILL LIKELY BRING DRY WEATHER FOR EARLY NEXT WEEK. FRONT IS FORECASTED TO STALL OVER THE GULF AND RETURN NORTH LATE IN THE WEEK. AT THIS TIME...WILL KEEP LOW POPS IN THE FORECAST ALTHOUGH LATEST MODELS ARE SHOWING A DEEPER MOISTURE PROFILE THIS CYCLE. MARINE...PERIODIC SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGH THE EARLY PART OF THE WEEKEND. OTHERWISE HIGH PRESSURE OVER THE EASTERN GULF AND LOW PRESSURE OVER WEST TEXAS WILL MAINTAIN ONSHORE FLOW THROUGH SUNDAY. MODELS CONTINUE TO BRING FRONT INTO THE NORTHERN GULF SUNDAY NIGHT ALLOWING FOR A BRIEF PERIOD OF OFFSHORE FLOW. WEAK TO MODERATE EASTERLY FLOW IS ANTICIPATED FOR EARLY NEXT WEEK AS HIGH PRESSURE SETTLES OVER THE SE U.S. && .PRELIMINARY POINT TEMPS/POPS... AEX 81 66 77 62 / 30 70 80 40 LCH 82 67 77 64 / 40 70 80 40 LFT 81 69 78 65 / 40 60 90 40 BPT 82 67 79 64 / 40 70 70 40 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR LAZ027>033- 041>045-052>055-073-074. TX...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR TXZ180-201-215- 216-259>262. GM...NONE. && $$ PUBLIC...04
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
616 AM CDT FRI APR 17 2015 .AVIATION...SINCE MIDNIGHT CONVECTIVE ACTIVITY HAS DECREASED SIGNIFICANTLY. RADAR NOW SHOWING JUST A FEW SHOWERS AND THUNDERSTORMS AND THESE OFFSHORE OVER THE NEAR COASTAL WATERS. TODAY LOOKS TO WITH MUCH LESS CONVECTION OVER THE AREA AS SOME SHARPLY DRIER MID LEVEL AIR ADVECTS INTO THE REGION. MODELS SUGGESTING A RAMPING UP OF PRECIP OVERNIGHT AS ANOTHER UPPER LEVEL DISTURBANCE APPROACHES. ALTOCU CLOUDS AT AROUND 10KT FT CURRENTLY OVER AREA. WILL SEE LOWER CLOUDS DEVELOP AS THE MORNING PROGRESSES BUT WILL MAINTAIN THESE WITHIN VFR. && .PREV DISCUSSION... /ISSUED 335 AM CDT FRI APR 17 2015/ DISCUSSION...POPS AND HEAVY RAIN WILL BE THE MAIN FORECAST ISSUES OVER THE NEXT 48 HOURS. WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY YESTERDAY AND OVERNIGHT WAS BEGINNING TO DECREASE AS OF 08Z. THE LATEST HRRR CONFIRMS THIS WITH ACTIVITY DECREASING SIGNIFICANT LATER THIS MORNING ESPECIALLY OVER EASTERN PARTS OF THE FORECAST AREA. WILL CONTINUE WITH FFA FOR NOW...BUT MAY CANCEL EARLY IF WEAKENING TREND CONTINUES. WILL TAPER POPS TO MID RANGE FOR THIS AFTERNOON. MODELS HAVE BEEN CONSISTENT IN LIFTING UPPER TROUGH NE THROUGH THE WEEKEND. ALSO...APPEARS THAT NEXT ROUND OF SHOWERS AND THUNDERSTORMS WILL BEGIN LATE TONIGHT AND BECOME MORE WIDESPREAD ON SATURDAY. WILL LIKELY NEED TO REISSUE FFA FOR TONIGHT AND SATURDAY. AFTER SATURDAY...A MUCH NEEDED PATTERN CHANGE IS FORECASTED. WEAK UPPER RIDGE SHOULD DEVELOP OVER THE GULF COAST STATES. A FRONTAL BOUNDARY SHOULD MOVE THROUGH THE AREA BY SUNDAY NIGHT AND THIS WILL LIKELY BRING DRY WEATHER FOR EARLY NEXT WEEK. FRONT IS FORECASTED TO STALL OVER THE GULF AND RETURN NORTH LATE IN THE WEEK. AT THIS TIME...WILL KEEP LOW POPS IN THE FORECAST ALTHOUGH LATEST MODELS ARE SHOWING A DEEPER MOISTURE PROFILE THIS CYCLE. MARINE...PERIODIC SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGH THE EARLY PART OF THE WEEKEND. OTHERWISE HIGH PRESSURE OVER THE EASTERN GULF AND LOW PRESSURE OVER WEST TEXAS WILL MAINTAIN ONSHORE FLOW THROUGH SUNDAY. MODELS CONTINUE TO BRING FRONT INTO THE NORTHERN GULF SUNDAY NIGHT ALLOWING FOR A BRIEF PERIOD OF OFFSHORE FLOW. WEAK TO MODERATE EASTERLY FLOW IS ANTICIPATED FOR EARLY NEXT WEEK AS HIGH PRESSURE SETTLES OVER THE SE U.S. && .PRELIMINARY POINT TEMPS/POPS... AEX 80 66 77 62 / 60 70 80 40 LCH 81 67 77 64 / 70 70 80 40 LFT 80 69 78 65 / 70 60 90 40 BPT 81 67 79 64 / 70 70 70 40 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLASH FLOOD WATCH UNTIL 1 PM CDT THIS AFTERNOON FOR LAZ027>033- 041>045-052>055-073-074. TX...FLASH FLOOD WATCH UNTIL 1 PM CDT THIS AFTERNOON FOR TXZ180-201- 215-216-259>262. GM...NONE. && $$ AVIATION...23
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1036 AM EDT FRI APR 17 2015 .SYNOPSIS... A SURFACE TROUGH WILL PASS THROUGH THE REGION TODAY. HIGH PRESSURE WILL RETURN FOR SATURDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY AND A WARM FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT INTO MONDAY. A COLD FRONT WILL PASS THROUGH LATE MONDAY INTO MONDAY NIGHT BEFORE HIGH PRESSURE RETURNS FOR THE MIDDLE PORTION OF NEXT WEEK. && .NEAR TERM /THROUGH SATURDAY/... 14Z MSAS AND SURFACE ANALYSIS INDICATES SURFACE TROUGH HAS REACHED WRN PA AND FAR EASTERN OH. THIS TROUGH WILL MOVE THROUGH THE FORECAST AREA THIS AFTN. SOME SCATTERED AREAS OF LIGHT RAIN SHOWERS AHEAD OF THIS BOUNDARY HAVE MOVED INTO WESTERN MD AND EASTERN WV. JUST TO THE EAST...SKIES HAVE CLEARED OVER MOST AREAS ALONG AND EAST OF THE SHENANDOAH VALLEY...ALLOWING TEMPS TO REACH WELL INTO THE 60S. TEMPS SHOULD RISE INTO THE L-M 70S BY AFTERNOON. NW FLOW WILL DRAW IN COLD DRY AIR ALOFT TODAY. THIS WILL CAUSE LAPSE RATES TO INCREASE. SHOWERS ARE EXPECTED TO FORM ALONG THE SFC TROUGH BY EARLY AFTERNOON. LATEST HRRR GUIDANCE SHOWS CONVECTIVE SHOWERS INCREASING IN COVERAGE BY EARLY AFTN IN THE SHENANDOAH VALLEY AND SPREADING EWD TOWARD THE BALTIMORE/WASHINGTON METRO AREAS. WARMER SFC TEMPS AND DECENT BOUNDARY LAYER MIXING WILL ALLOW SEVERAL HUNDRED J/KG OF CAPE. A FEW THUNDERSTORMS ARE POSSIBLE LATE THIS AFTERNOON AND EARLY EVENING. CLEARING IS EXPECTED BEHIND THE SFC TROUGH INTO THE EVENING. HIGH PRESSURE WILL MOVE INTO THE REGION TONIGHT AND PERSIST SATURDAY. FCST MIN TEMPS INT HE 50S EXPECTED TONIGHT. FULL SUNSHINE WILL ALLOW TEMPS TO RISE INTO THE UPPER 70S TO NEAR 80 IN THE METROS SATURDAY. && .SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/... REGION REMAINS ON THE SOUTHERN PERIPHERY OF HIGH PRESSURE CENTERED JUST NORTH OF THE GREAT LAKES. RIDGING BUILDS IN ALOFT...WITH THE RIDGE AXIS SHIFTING ACROSS THE MID ATLANTIC BY SUN MORNING. OVERALL PATTERN WILL KEEP THE AREA DRY. CLOUDS WILL BEGIN TO INCREASE FROM THE SOUTHWEST AHEAD OF THE NEXT FRONTAL SYSTEM. WINDS WILL LIGHTEN AND BECOME NE OVERNIGHT AS THE HIGH BUILDS SOUTH. && .LONG TERM /MONDAY THROUGH THURSDAY/... 00Z MODEL SUITE CONTINUING WITH A SLOWER PROGRESSION OF THE NEXT FRONTAL SYSTEM...AND THE ARRIVAL TIMING OF THE PCPN. RIDGE AXIS SHIFTS EAST DURING THE DAY SUNDAY AS A DEEPENING CLOSED LOW OVER THE NORTHERN PLAINS BUILDS EAST. BROAD LOW PRESSURE AT THE SFC OVER THE CENTRAL PLAINS BECOMES ORGANIZED DURING HE DAY AS WELL AS IT MOVES INTO THE WESTERN GREAT LAKES...GRADUALLY LIFTING THE ASSOCIATED WARM FRONT TO THE NORTH AND INTO THE MID ATLANTIC. GENERAL CONSENSUS AMONGST THE MODELS KEEPS THE WARM FRONT AT OR JUST SOUTH OF THE VA/NC BORDER THRU SUN NIGHT...WITH PCPN OCCURRING SUN-SUN NIGHT AS A RESULT OF DYNAMIC FORCING ALOFT WITH MULTIPLE MID LVL SHORTWAVES AND STRENGTHENING LLJ AND 250MB JET. PWATS INCRSG TO BETWEEN 1.2-1.4 IN...WHICH COULD RESULT IN PERIODS OF MODERATE TO HEAVY RAIN. SOME UNCERTAINTY STILL EXISTS WITH PCPN TIMING AND TSTM DEVELOPMENT ON MONDAY. WARM FRONT LOOKS TO BE NEAR THE VA/NC BORDER EARLY MONDAY...THEN GRADUALLY LIFTING NORTH DURING THE DAY. HOW QUICKLY IT CAN CLEAR THE CWA AND WARM SECTOR THE AREA WILL AFFECT THE EXTENT OF TSTM DEVELOPMENT...AND AS SUCH WILL CONTINUE TO MENTION SLIGHT CHC T FOR MOST OF THE AREA NOW...AND CHC OVER CENTRAL VA WHERE THE BEST DAYTIME HEATING SHOULD OCCUR. KEPT NORTHEASTERN MD OUT OF THE THUNDER MENTION FOR NOW WITH COOLER TEMPS EXPECTED. IN ADDITION...THINKING THERE SHOULD BE TWO ROUNDS OF PCPN...THE INITIAL SUN NIGHT...WITH A BREAK AT SOME POINT MONDAY WITH THE NEXT ROUND MOVING IN AHEAD OF THE APPROACHING COLD FRONT. THE COLD FRONT PUSHES THROUGH MONDAY NIGHT...WITH PCPN CLEARING TO THE EAST BY EARLY TUES MORNING. SFC HIGH PRESSURE BUILDS IN FROM THE SOUTH IN THE WAKE OF THE FRONT THRU WED...QUICKLY PROGRESSING OFFSHORE BY THURS...AND RESULTING IN BRIEF PERIOD OF DRY WX. THE REGION REMAINS POSITIONED AT THE BASE OF A BROAD UPPER LVL CLOSED LOW...WHICH WILL SEND THROUGH THE NEXT COLD FRONT MIDWEEK...BRINGING THE NEXT CHC FOR PCPN. NEAR NORMAL TEMPS EXPECTED THROUGH THE PERIOD ON WLY FLOW. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... VFR WITH DRY CONDITIONS EXPECTED AT THE TERMINALS THROUGH NOON. A SFC TROUGH ACROSS THE OHIO VALLEY WILL MOVE FROM WEST TO EAST ACROSS THE TERMINALS THIS AFTERNOON. SHOWERS WILL REDEVELOP. AN ISOLATED TS IS POSSIBLE MAINLY CHO-DCA. IN TERMS OF WINDS...SW FLOW IN THE MORNING WITH POTENTIAL FOR GUSTS TO AROUND 15 KT. GUSTS ARE EXPECTED TO DIMINISH BY EARLY AFTERNOON. WINDS WILL SHIFT TO THE W THIS AFTN AND EVENTUALLY TO THE NW BY LATE AFTERNOON. VFR CONDITIONS EXPECTED TONIGHT AND SATURDAY. VFR CONDITIONS SAT NIGHT-SUN. SUB-VFR CONDITIONS BCMG LIKELY BY SUN NIGHT WITH WIDESPREAD RAIN. PERIODS OF HEAVIER RAIN COULD DROP CONDITIONS TO SUB-IFR SUN NIGHT. LLWS CONCERNS PSBL MON MORNING WITH SE WINDS 40-50 KTS AT 2KFT...SHIFTING TO THE SOUTH DURING THE MORNING. SUB-VFR CONDITIONS REMAIN PSBL DURING THE DAY MON AS A COLD FRONT BRINGS ANOTHER ROUND OF PCPN. SLIGHT CHC OF THUNDER CURRENTLY FOR THE TAF SITES...MAINLY MON AFTN/EVENING. WIND SHIFT EXPECTED MON EVENING WITH FRONTAL PASSAGE. VFR CONDITIONS MON NIGHT AS THE PCPN TAPERS OFF...LASTING THRU WED. && .MARINE... SCA HAS BEEN CANCELLED...AS WINDS HAVE DIMINISHED TO AROUND 10KT OVER MOST OF THE WATERS. A SFC TROUGH WILL CROSS THE WATERS THIS AFTERNOON. SHOWERS ARE EXPECTED AND AN ISOLATED THUNDERSTORM IS POSSIBLE MAINLY ACROSS THE SOUTHERN WATERS. S WINDS BECOME W-NW THIS EVENING. HIGH PRESSURE BUILDS IN TONIGHT AND SATURDAY. GENERALLY SUB-SCA CONDITIONS SAT NIGHT-SUN. SCA CONDITIONS PSBL BY SUN NIGHT WITH INCRSG ELY FLOW. SCA CONDITIONS LAST DURING THE DAY MON AHEAD OF THE COLD FRONT...BCMG SUB-SCA MON EVENING. GUSTS TO 20 KTS PSBL AGAIN TUES AFTN IN THE WAKE OF THE FRONT. && .EQUIPMENT... AUDIO DEGRADATION AT THE NOAA WEATHER RADIO CHARLOTTESVILLE TRANSMITTER IS EXPECTED TO CONTINUE THROUGH THIS WEEKEND. TECHNICIANS ARE SCHEDULED TO PERFORM MAINTENANCE AT THE TRANSMITTER SITE MONDAY. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...SEARS/KCS NEAR TERM...HAS/KCS SHORT TERM...HAS LONG TERM...SEARS AVIATION...SEARS/HAS/KCS MARINE...SEARS/HAS/KCS EQUIPMENT...KCS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
751 AM EDT FRI APR 17 2015 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO MOVE OFF THE COAST THIS MORNING. A SURFACE TROUGH WILL PASS THROUGH THE REGION TODAY AND HIGH PRESSURE WILL RETURN FOR SATURDAY. THE HIGH WILL MOVE OFF THE COAST SUNDAY AND A WARM FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT INTO MONDAY. A COLD FRONT WILL PASS THROUGH LATE MONDAY INTO MONDAY NIGHT BEFORE HIGH PRESSURE RETURNS FOR THE MIDDLE PORTION OF NEXT WEEK. && .NEAR TERM /THROUGH SATURDAY/... HIGH PRESSURE WILL PERSIST OFF THE EAST COAST THIS MORNING. AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE MID-ATLANTIC THIS MORNING...FOLLOWED BY A SURFACE TROUGH LATER TODAY. EARLIER SHOWER ACTIVITY HAS MOVED INTO THE DELMARVA REGION. SOME SCATTERED AREAS OF LIGHT RAIN ASSOCIATED WITH THE UPPER TROUGH TO OUR WEST ARE APPROACHING THE HIGHLANDS. FURTHER EAST... A PERIOD OF DRY CONDITIONS IS EXPECTED THIS MORNING BETWEEN THE EXITING UPPER LEVEL DISTURBANCE AND INCOMING SFC TROUGH. TEMPS SHOULD RISE INTO THE L-M 70S BY AFTERNOON. NW FLOW WILL DRAW IN COLD DRY AIR ALOFT TODAY. THIS WILL CAUSE LAPSE RATES TO INCREASE AND SHOWERS ARE EXPECTED TO FORM ALONG THE SFC TROUGH BY EARLY AFTERNOON. LATEST HRRR GUIDANCE SHOWS A BKN LINE OF CONVECTIVE SHOWERS TO MOVE E-SE THROUGH THE AFTERNOON. AS THE SHOWERS MOVE PAST I-66...WARMER SFC TEMPS AND DECENT BOUNDARY LAYER MIXING WILL ALLOW A FEW HUNDRED J/KG OF CAPE. A FEW THUNDERSTORMS ARE POSSIBLE SOUTH OF I-66/MD RT50 LATE THIS AFTERNOON AND EARLY EVENING. CLEARING IS EXPECTED BEHIND THE SFC TROUGH INTO THE EVENING. HIGH PRESSURE WILL MOVE INTO THE REGION TONIGHT AND PERSIST SATURDAY. FCST MIN TEMPS INT HE 50S EXPECTED TONIGHT. FULL SUNSHINE WILL ALLOW TEMPS TO RISE INTO THE UPPER 70S TO NEAR 80 IN THE METROS SATURDAY. && .SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/... REGION REMAINS ON THE SOUTHERN PERIPHERY OF HIGH PRESSURE CENTERED JUST NORTH OF THE GREAT LAKES. RIDGING BUILDS IN ALOFT...WITH THE RIDGE AXIS SHIFTING ACROSS THE MID ATLANTIC BY SUN MORNING. OVERALL PATTERN WILL KEEP THE AREA DRY. CLOUDS WILL BEGIN TO INCREASE FROM THE SOUTHWEST AHEAD OF THE NEXT FRONTAL SYSTEM. WINDS WILL LIGHTEN AND BECOME NE OVERNIGHT AS THE HIGH BUILDS SOUTH. && .LONG TERM /MONDAY THROUGH THURSDAY/... 00Z MODEL SUITE CONTINUING WITH A SLOWER PROGRESSION OF THE NEXT FRONTAL SYSTEM...AND THE ARRIVAL TIMING OF THE PCPN. RIDGE AXIS SHIFTS EAST DURING THE DAY SUNDAY AS A DEEPENING CLOSED LOW OVER THE NORTHERN PLAINS BUILDS EAST. BROAD LOW PRESSURE AT THE SFC OVER THE CENTRAL PLAINS BECOMES ORGANIZED DURING HE DAY AS WELL AS IT MOVES INTO THE WESTERN GREAT LAKES...GRADUALLY LIFTING THE ASSOCIATED WARM FRONT TO THE NORTH AND INTO THE MID ATLANTIC. GENERAL CONSENSUS AMONGST THE MODELS KEEPS THE WARM FRONT AT OR JUST SOUTH OF THE VA/NC BORDER THRU SUN NIGHT...WITH PCPN OCCURRING SUN-SUN NIGHT AS A RESULT OF DYNAMIC FORCING ALOFT WITH MULTIPLE MID LVL SHORTWAVES AND STRENGTHENING LLJ AND 250MB JET. PWATS INCRSG TO BETWEEN 1.2-1.4 IN...WHICH COULD RESULT IN PERIODS OF MODERATE TO HEAVY RAIN. SOME UNCERTAINTY STILL EXISTS WITH PCPN TIMING AND TSTM DEVELOPMENT ON MONDAY. WARM FRONT LOOKS TO BE NEAR THE VA/NC BORDER EARLY MONDAY...THEN GRADUALLY LIFTING NORTH DURING THE DAY. HOW QUICKLY IT CAN CLEAR THE CWA AND WARM SECTOR THE AREA WILL AFFECT THE EXTENT OF TSTM DEVELOPMENT...AND AS SUCH WILL CONTINUE TO MENTION SLIGHT CHC T FOR MOST OF THE AREA NOW...AND CHC OVER CENTRAL VA WHERE THE BEST DAYTIME HEATING SHOULD OCCUR. KEPT NORTHEASTERN MD OUT OF THE THUNDER MENTION FOR NOW WITH COOLER TEMPS EXPECTED. IN ADDITION...THINKING THERE SHOULD BE TWO ROUNDS OF PCPN...THE INITIAL SUN NIGHT...WITH A BREAK AT SOME POINT MONDAY WITH THE NEXT ROUND MOVING IN AHEAD OF THE APPROACHING COLD FRONT. THE COLD FRONT PUSHES THROUGH MONDAY NIGHT...WITH PCPN CLEARING TO THE EAST BY EARLY TUES MORNING. SFC HIGH PRESSURE BUILDS IN FROM THE SOUTH IN THE WAKE OF THE FRONT THRU WED...QUICKLY PROGRESSING OFFSHORE BY THURS...AND RESULTING IN BRIEF PERIOD OF DRY WX. THE REGION REMAINS POSITIONED AT THE BASE OF A BROAD UPPER LVL CLOSED LOW...WHICH WILL SEND THROUGH THE NEXT COLD FRONT MIDWEEK...BRINGING THE NEXT CHC FOR PCPN. NEAR NORMAL TEMPS EXPECTED THROUGH THE PERIOD ON WLY FLOW. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... ANY LEFTOVER MVFR CIGS WILL IMPROVE TO VFR OVER THE NEXT HOUR OR SO. THEN VFR WITH DRY CONDITIONS EXPECTED THROUGH NOON. A SFC TROUGH ACROSS THE OHIO VALLEY WILL MOVE FROM WEST TO EAST ACROSS THE TERMINALS THIS AFTERNOON. SHOWERS WILL REDEVELOP. AN ISOLATED TS IS POSSIBLE MAINLY CHO-DCA. IN TERMS OF WINDS...SW FLOW IN THE MORNING WITH POTENTIAL FOR GUSTS TO AROUND 15 KT. GUSTS ARE EXPECTED TO DIMINISH BY EARLY AFTERNOON. WINDS WILL SHIFT TO THE W THIS AFTN AND EVENTUALLY TO THE NW BY LATE AFTERNOON. VFR CONDITIONS EXPECTED TONIGHT AND SATURDAY. VFR CONDITIONS SAT NIGHT-SUN. SUB-VFR CONDITIONS BCMG LIKELY BY SUN NIGHT WITH WIDESPREAD RAIN. PERIODS OF HEAVIER RAIN COULD DROP CONDITIONS TO SUB-IFR SUN NIGHT. LLWS CONCERNS PSBL MON MORNING WITH SE WINDS 40-50 KTS AT 2KFT...SHIFTING TO THE SOUTH DURING THE MORNING. SUB-VFR CONDITIONS REMAIN PSBL DURING THE DAY MON AS A COLD FRONT BRINGS ANOTHER ROUND OF PCPN. SLIGHT CHC OF THUNDER CURRENTLY FOR THE TAF SITES...MAINLY MON AFTN/EVENING. WIND SHIFT EXPECTED MON EVENING WITH FRONTAL PASSAGE. VFR CONDITIONS MON NIGHT AS THE PCPN TAPERS OFF...LASTING THRU WED. && .MARINE... SHOWERS HAVE MOVED EAST OF THE WATERS. SOUTHERLY CHANNELING IS EXPECTED THIS MORNING AS A PRESSURE GRADIENT TIGHTENS ACROSS THE WATERS. A SCA IS IN EFFECT FOR THE LOWER TIDAL POTOMAC AND MD CHESAPEAKE BAY FOR GUSTS 18-20KTS. A SFC TROUGH WILL CROSS THE WATERS THIS AFTERNOON. SHOWERS ARE EXPECTED AND AN ISOLATED THUNDERSTORM IS POSSIBLE MAINLY ACROSS THE SOUTHERN WATERS. S WINDS BECOME W-NW THIS EVENING. HIGH PRESSURE BUILDS IN TONIGHT AND SATURDAY. GENERALLY SUB-SCA CONDITIONS SAT NIGHT-SUN. SCA CONDITIONS PSBL BY SUN NIGHT WITH INCRSG ELY FLOW. SCA CONDITIONS LAST DURING THE DAY MON AHEAD OF THE COLD FRONT...BCMG SUB-SCA MON EVENING. GUSTS TO 20 KTS PSBL AGAIN TUES AFTN IN THE WAKE OF THE FRONT. && .EQUIPMENT... AUDIO DEGRADATION AT THE NOAA WEATHER RADIO CHARLOTTESVILLE TRANSMITTER IS EXPECTED TO CONTINUE THROUGH THIS WEEKEND. TECHNICIANS ARE SCHEDULED TO PERFORM MAINTENANCE AT THE TRANSMITTER SITE MONDAY. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ530>534- 537>543. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR ANZ530>534- 537>543. && $$ SYNOPSIS...SEARS NEAR TERM...HAS/KCS SHORT TERM...HAS LONG TERM...SEARS AVIATION...SEARS/HAS/KCS MARINE...SEARS/HAS/KCS EQUIPMENT...KCS
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
643 AM CDT Fri Apr 17 2015 .DISCUSSION... Issued at 435 AM CDT FRI APR 17 2015 Today - Tonight: Today will be a transition day. An upper ridge, now overhead, has kept the KS/OK/TX Panhandle convection at bay since yesterday. However, as the upper ridge nudges east this convection will be able to edge closer and closer. This activity has been generated by weak impulses ejecting from a cut-off upper low near the 4-corners area and mid-level frontogenesis. This upper low has moved little over the past 24 hours as it awaits its kicker which is just now crossing into British Columbia. This latter feature is expected to strengthen later today as upstream ridging sharpens and forces this shortwave trough to dig southeast into the Northern Rockies...but not until tomorrow. What this means is any convection reaching the CWA today will weaken/fall apart as it moves away from the better upper support. Having said that there are some signals from the last couple runs of the HRRR and to a lesser extent the 00z NAM that convection now moving east through northern OK/south central KS could reach the far western counties by around the noon hour. Regional radars show an outflow boundary now expanding east from the KS convection with new activity sprouting over north central OK. This activity is what the HRRR picks up on and lifts northeast later this morning. So, will slowly shift chance PoPs across the far western CWA today while leaving the eastern half dry. Convective debris clouds will also thin as they spread east today providing a thin veil of high clouds. This shouldn`t hold back warming and expect temperatures to top out in the middle and upper 70s. The Southern Plateau closed low will gradually shift east tonight, allowing new convection to push further east and become more organized as it reaches the KS/MO state line towards sunrise. Will handle this with a steady and gradual increase in PoPs through the night. Saturday - Sunday: A very wet period with convection becoming numerous and likely coming in waves as cells track nne while shifting slowly east. Model precipitable water values 2 to 3 standard deviations are a cause for concern. Steering winds in the 20kt area plus this moisture heighten the threat of localized flooding. Have increased qpf and this may even be underdone as its certainly feasible that some areas could see up to 2 inches of rain through Saturday night. Extensive cloud cover and rain-cooled air forces me to lower highs on both days and won`t be surprised if they are lowered further in future forecasts. Modest MLCAPEs and 0-6km shear in the 20-30kt range are not likely to support any severe threat on Saturday. Sunday may be a slightly different story. By then the closed upper low will have opened up and accelerated eastward. There is a chance we could be rain free Sunday morning with some partial sunshine. Should this occur more robust afternoon convection could form within a marginally supportive airmass featuring MLCAPEs of 1200-1400 J/kg but only 25-30kt 0-6 km bulk shear. Monday - Friday: The shortwave trough which will act as the kicker to move the current closed upper low near the 4-corners will have formed into a well developed upper trough from the Upper MS Valley through the Mid MO Valley early in this period. As the upper trough axis passes through on Monday strong subsidence and cold air advection will provide ample sunshine but below average temperatures through Tuesday. By mid week, an upper ridge axis will build east into the Central Plains with warm air advection spreading east. The GFS is more aggressive and faster than the ECMWF in pushing weak mid level vorticity lobes through the ridge axis. These features will be ejected from a broad upper trough that will works into the desert southwest. Difficult to determine how soon any scattered convection could work its way back into the region. For now will introduce some low chance PoPs for late Wednesday into Thursday. The current closed upper low now over northern Mexico is expected to weaken as it lifts north-northeast through the Central Plains and CWA. While there should be decent moisture lifted northward with this feature minimal instability will limit amount of thunder. Given that the operational models have been generating a similar solution believe 30-40 PoPs are warranted for scattered convection. Thursday - Sunday: Roll of the dice as to how weather will evolve from Thursday through Sunday. Not especially fond of the blended model approach of carpet bombing chance PoPs in every period. The medium range models drop a deep upper trough into the Desert Southwest and then cut it off. Models typically are challenged significantly with these features initially. They tend to lift them out too soon and too far east. Will be interesting to see how this system is handled going forward. Difficult trying to time any weak impulse ejected from this system within the downstream southwesterly flow. For now will handle this with low chance PoPs with above average temperatures. && .AVIATION...(For the 12Z TAFS through 12Z Saturday Morning) Issued at 639 AM CDT FRI APR 17 2015 Generally VFR conditions through this evening with a steady stream of higher based clouds. Watching a band of showers and storms over north central OK and south central KS that are starting to turn to the northeast. Seeing signs this activity could lift through far eastern KS and western MO but weaken during the afternoon hours. Rest of northern and central MO should stay dry through the afternoon hours. If current trends continue will likely need to amend forecast and increase chances for thunder. Should see a lull in activity this evening but another round of more robust convection should form over KS tonight and reach far eastern KS and western MO during the pre- dawn hours of Saturday morning. Should see MVFR visibilities with this batch of showers and storms. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...MJ
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1045 AM EDT FRI APR 17 2015 .SYNOPSIS... A WEAK COLD FRONT WILL MOVE ACROSS CENTRAL NEW YORK EARLY THIS AFTERNOON AND NORTHEAST PENNSYLVANIA BY LATE AFTERNOON. THIS FRONT WILL TRIGGER A FEW SHOWERS WITH AN ISOLATED THUNDERSTORM IN NORTHEAST PENNSYLVANIA. ANOTHER COLD FRONT WILL PASS ACROSS THE REGION SATURDAY. THIS FRONT COULD TRIGGER SOME SHOWERS IN NORTHERN AND EASTERN NEW YORK WITH MAINLY DRY WEATHER IN CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. HIGH PRESSURE AND COOLER WEATHER WILL BUILD ACROSS THE REGION FOR SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WATER VAPOR IMAGERY SHOWS A SHORT WAVE MOVING ACROSS THE EASTERN GREAT LAKES AND EASTERN OHIO VALLEY THIS MORNING. THIS WAVE WILL PUSH A WEAK FRONT ACROSS THE REGION THIS AFTERNOON WITH SOME LL DRY ADVECTION BEHIND THE FRNT. THE FRONT AND LIFT ASSCTD WITH THE SHRT WAVE WILL TRIGGER ISLD TO SCT SHRA ACRS C NY/NE PA THIS AFTERNOON. THE FRNT COMES THRU AT MAX HEATING LATE THIS AFTERNOON ESP IN NE PA. CAPES ON THE HI RES MODELS NOW ARE RANGING FROM ARND 250 TO 500 J/KG IN NE PA ARND 21Z WITH THE HIGHER RESOLUTION MODELS SHOWING SCT CONVECTIVE CELLS FORMING ON SIMULATED RADAR FIELDS. THE BULK SHEAR IS ARND 20 KNOTS 0-1 KM AND 0-3 KM AND ABT 35 KNOTS 0-6 KM. FORCING IS NOT STRG BUT I HAVE ADDED ISLD TSRA TO NE PA GRIDS. I MAY HAVE TO ADJUST THIS UP EVEN MORE AS RECENT RAP AND HRRR RUNS HAVE MORE CAPE. WILL CONT TO MONITOR. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... NW FLOW ALOFT TNGT WITH WEAK SFC FEATURES WILL RESULT IN A QUIET PD WITH LGT WINDS AND BKN CLDS. WHILE A SHWR CAN/T BE RULED OUT...NOT ENUF OF A CHANCE TO INCLUDE IN THE FCST ATTM. SATURDAY WILL SEE A SHRT WV PASSING THRU NRN NEW ENG AND SOME LATE DAY CAA IN THE WAKE OF THE WV. MODELS SHOW VERY DRY AIR OVER THE AREA WITH THE BEST FRCG STAYING TO THE NE. SOME INSTABILITY LIKELY WITH THE LWRD HGTS BUT DRY AIR SHD INHIBIT ANY SHWRS FROM FRMG IN THE FCST AREA...ALTHOUGH NRN ONEIDA WILL BE CLOSE. UPR RDGG OVER THE GREAT LAKES WILL ALLOW SFC HIPRES TO SLIDE INTO THE AREA ON SUNDAY. TEMPS WILL BE A BIT LWR WITH THE CAA BUT DRIER AIR SHD ALLOW FOR MSTLY SUNNY SKIES. && .LONG TERM /MONDAY THROUGH THURSDAY/... 0245 AM UPDATE...ONLY MADE A FEW ADJUSTMENTS TO PREVIOUS FORECAST MADE DURING THE DAY SHIFT THURSDAY. MAIN CHANGE WAS TO ADJUST HIGH TEMPS DOWN FOR MONDAY, WEDNESDAY, AND THURSDAY OF NEXT WEEK AS GUIDANCE CONTINUES TO INDICATE WE WILL BE COOLER AND MORE UNSETTLED UNDER THE INFLUENCE OF AN UPPER LEVEL TROUGH. 445 PM THURSDAY UPDATE... MODELS IN GOOD AGREEMENT ON MOIST OCCLUDED FRONT LIKELY TO BRING RAIN AS IT SWEEPS THROUGH THE REGION LATE SUNDAY NIGHT THROUGH MONDAY. SHOWALTER INDICES ONLY GET TO AROUND ZERO...SHOWING ONLY SMALLEST HINT OF ELEVATED INSTABILITY...SO CHANCE OF EMBEDDED THUNDER DURING THAT PERIOD LOOKS MINIMAL TO NONE. QUARTER TO HALF INCH OF RAIN LOOKS QUITE DOABLE HOWEVER. CUTOFF LOW CURRENTLY OVER FOUR CORNERS REGION...IS DEPICTED BY GFS-ECMWF TO MERGE WITH A DIGGING NORTHERN STREAM TROUGH OVER THE MIDWEST THIS WEEKEND. THOSE FEATURES WILL COMBINE INTO A NEW LARGER CUTOFF LOW...THE CENTER OF WHICH WILL SLOWLY SLOG ITS WAY OVER THE WESTERN GREAT LAKES NEXT WEEK. THIS UPPER LOW WILL HAVE A LARGE FOOTPRINT WITH DISTURBANCES-WAVES ROTATING AROUND IT ACROSS GREAT LAKES TO NORTHEAST. MODELS DISAGREE ON LOCATION OF UPPER LOW CENTER BY THURSDAY /EITHER CENTRAL GREAT LAKES AND HEADING EAST...OR A BIT FURTHER NORTH AND STILL PARKED/ YET EITHER WAY IT LOOKS RATHER TROUGHY AND UNSETTLED WITH CYCLONIC FLOW OVER OUR REGION. SO AFTER BRIEFLY MILDER CONDITIONS TUESDAY...WE SHOULD TREND BACK TO NEAR CLIMATOLOGY FOR TEMPERATURES WEDNESDAY-THURSDAY. IF THE UPPER LOW SHIFTS EAST AS PER ECMWF...POSSIBLY A LITTLE COOLER THAN CLIMATOLOGY. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... 12Z UPDATE... SHOWERS WILL CONTINUE DIMINISHING OVER THE AREA FROM WEST TO EAST THIS MORNING HOWEVER STILL EXPECTING AT LEAST MVFR FUEL ALT CONDITIONS FOR MOST SITES UNTIL THIS AFTERNOON DUE TO LOW CIGS. FOR KBGM, CIGS WILL LIKELY DROP AT TIMES TO HIGH END IFR THIS MORNING WITH IFR VISBYS LIKELY AT TIMES FOR KRME. CONDITIONS IMPROVE TO VFR AT ALL SITES THIS AFTERNOON WITH SKIES CLEARING OUT TONIGHT. WINDS WILL GENERALLY BE W/SW AROUND 5 KNOTS EARLY THIS MORNING BECOMING W/NW 5 TO 10 KNOTS BY THIS AFTERNOON. .OUTLOOK... SAT THRU SUN...VFR. SUN NGT-MON-TUE...RESTRICTIONS IN -RA...ESP. SUN NGT-MON. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJN NEAR TERM...DJN SHORT TERM...DGM LONG TERM...MDP/PCF AVIATION...PCF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1027 AM EDT FRI APR 17 2015 .SYNOPSIS... A WEAK PRESSURE PATTERN WILL CONTINUE TO BRING MOSTLY CLOUDY SKIES AND DRIZZLY CONDITIONS TODAY. SOME IMPROVEMENT CAN BE EXPECTED SATURDAY AND SUNDAY. A WARM FRONT BRING ANOTHER GOOD CHANCE OF RAIN LATER SUNDAY. NEXT WEEK LOOKS TO BE DRY AND SEASONABLE. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM FRIDAY...LIGHT SHOWERS AND DRIZZLE CONTINUE ACROSS THE AREA THIS MORNING. SOME OF THE ACTIVITY NEAR WILMINGTON HAS BEEN A LITTLE HEAVIER. HRRR AND LATEST NAM SHOW A CONVECTIVE SIGNAL IN THEIR RESPECTIVE MODELS WHICH SHOW SHOWERS INCREASING THIS AFTERNOON. WILL MAINTAIN LOW CHANCE POPS AREAWIDE. FORECAST EMPHASIS THEN SHIFTS TO POSSIBLE OVERNIGHT ACTIVITY WITH THE SHORTWAVE IN THE TENNESSEE VALLEY. THE LATEST NAM IS A LITTLE LESS ROBUST BUT WILL WAIT UNTIL THE 1200 UTC GFS ARRIVES TO MAKE ANY CHANGES. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 300 AM FRIDAY...THE FORECAST AREA WILL BE UNDER THE CONTROL OF NEARLY A FULL LATITUDE AMPLIFIED UPPER RIDGE THIS PERIOD. THE ROUGHLY NORTH TO SOUTH UPPER RIDGE AXIS WILL REMAIN WEST OF THE ILM CWA DURING SAT. WITH WEAK HIGH PRESSURE AT THE SFC AND MAINLY SUBSIDENCE ALOFT...THE CHANCE FOR CONVECTION HAS BEEN KEPT TO A MINIMUM AND WILL ONLY INDICATE SEA BREEZE INDUCED CONVECTION. THE UPPER RIDGE AXIS WILL DRIFT TO THE EAST AND ACROSS THE ILM CWA SAT NIGHT...AND FINALLY OFF THE CAROLINA COASTS SUN THRU SUN NIGHT. MODELS ARE IN DECENT AGREEMENT WITH THIS SCENARIO PANNING OUT. A POTENT S/W MID-LEVEL TROF OR ONE COULD CALL IT A CLIPPER...WILL DIVE SE AND RACE ACROSS THE NE STATES SAT...AND OFFSHORE FROM NEW ENGLAND BY SUNDAY. THE SFC COLD FRONT ASSOCIATED WITH THIS CLIPPER WILL BACKDOOR THE ILM CWA ON SUN FOLLOWED BY A WEDGE OF HIGH PRESSURE FROM THE NORTH THRU SUN NIGHT. POPS WILL BE ON THE LOW SIDE IF ANY WITH THIS FRONTAL PASSAGE. THE CENTRAL U.S. CUTOFF LOW IS PROGGED TO OPEN UP AND HOOK ONTO A S/W UPPER TROF DIVING OUT OF CENTRAL CANADA BY THE END OF THIS PERIOD. LOOK FOR AN AMPLIFYING PATTERN ALOFT WITH THE FA COMING UNDER THE INFLUENCE OF THE FULL LATITUDE UPPER TROF ACROSS THE CENTRAL U.S. BY LATE SUN. WITH SW FLOW ALOFT...GULF OF MEXICO MOISTURE WILL BECOME WELL TAPPED BY MID TO LATE SUN. A S/W MID- LEVEL TROF ROTATING THRU THE WELL AMPLIFIED UPPER PATTERN...WILL PUSH ACROSS THE FA BY LATE SUN INTO EARLY MON. THE DYNAMICS ASSOCIATED WITH IT AND THE STALLED SFC BOUNDARY IN THE VICINITY... WILL BE ENOUGH TO INCREASE POPS TO LIKELY OR POSSIBLY CATEGORICAL...BY AND DURING SUN NIGHT ACROSS THE ENTIRE ILM CWA. AS FOR TEMPS THIS PERIOD...WILL GO WITH AT OR SLIGHTLY ABOVE CLIMO WHICH IS BASICALLY 70S TO AROUND 80 FOR HIGHS...AND 50S TO AROUND 60 FOR LOWS. && .LONG TERM /MONDAY THROUGH THURSDAY/... AS OF 300 AM FRIDAY...A WELL AMPLIFIED LONGWAVE UPPER PATTERN TO BECOME ESTABLISHED THIS PERIOD. THE ILM CWA WILL PRIMARILY BE UNDER THE INFLUENCED OF NEARLY A FULL LATITUDE UPPER TROF...WITH THE UPPER TROF N-S AXIS REMAINING WEST OF THE ILM CWA THIS PERIOD. ITS ONLY TOWARD THE END OF THE LONG TERM PERIOD WHEN MODELS WANT TO FLATTEN THIS AMPLIFIED FLOW...WITH MODELS DIVERGING FROM ONE ANOTHER FOR THEIR RESPECTIVE SOLUTIONS BY THE MID-LATE WEEK PERIOD OF NEXT WEEK. AS FOR POPS...THE PCPN FROM SUN NIGHT WILL EXTEND INTO EARLY MON BEFORE MOVING OFF TO THE NE. A COLD FRONT WILL APPROACH AND PUSH ACROSS THE ILM CWA MON NIGHT INTO TUE...WITH IDLEST CHANCE POPS BEING ADVERTISED. WEAK HIGH PRESSURE WILL FOLLOW FROM THE GULF COAST STATES TUE THRU MUCH OF THE MID-WEEK PERIOD OF NEXT WEEK. THIS COULD END UP FINALLY BEING A PERIOD OF DRYING OUT ACROSS THE ILM CWA. AS FOR MAX/MIN TEMPS THIS PERIOD...STAYED AT OR SLIGHTLY HIGHER THAN CLIMO FOR THIS TIME OF THE YEAR. DO NOT SEE ANY INFLUENCE OF COOL OR COLDER THAN NORMAL AIR MASSES AFFECTING THE ILM CWA DURING THIS TIME PERIOD. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... AS OF 12Z...LOW PRESSURE REMAINS OFFSHORE...WITH SMALL POCKETS OF LIGHT SHOWERS MOVING ONSHORE. MOST OF THE SHOWERS WILL REMAIN AWAY FROM THE TERMINALS...BUT A SMALL SHOWER IS NOT OUT OF THE QUESTION. NORTHEAST FLOW IS EXPECTED TO CONTINUE TODAY...WITH MAINLY MVFR CEILINGS. TONIGHT...A MORE ORGANIZED SHORT WAVE WILL MOVE WEST TO EAST ACROSS THE REGION...WITH MORE ORGANIZED PRECIPITATION EXPECTED. CEILINGS MAY LOWER TO IFR...BUT WILL KEEP PREDOMINATELY MVFR AT THIS TIME. EXTENDED OUTLOOK...VFR SATURDAY. SHOWERS MOVING BACK INTO THE REGION LATE SATURDAY NIGHT THROUGH MONDAY MORNING. BECOMING VFR MONDAY AFTERNOON THROUGH TUE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM FRIDAY...WINDS AND SEAS ON THE WAY DOWN THIS MORNING WITH JMPN7 REPORTING EIGHT KNOTS FROM THE NORTHEAST. SEAS AT 41110 NOW BELOW FIVE FEET. FORECAST LOOKS GOOD WITH HEADLINES EXPIRING AS THE DAY PROCEDES. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 300 AM FRIDAY...SATURDAY TO START OFF WITH A WEAK SFC PRESSURE PATTERN AND GRADIENT. BY THE END OF THE DAY AND DURING SAT NIGHT...A BACKDOOR CUP IS EXPECTED TO OCCUR. IMMEDIATELY FOLLOWING THE CUP...A WEDGE OF HIGH PRESSURE WILL NOSE DOWN FROM SE CANADA AND THE NE STATES SAT NIGHT THRU SUN. THE SFC PRESSURE GRADIENT WILL TIGHTEN FOR THE REMAINDER OF THE SHORT TERM PERIOD WITH NE WINDS REACHING SCEC OR POSSIBLY SCA THRESHOLDS LATE SAT INTO EARLY SUN. A COASTAL FRONT/TROF WILL DEVELOP AND BECOME ESTABLISHED JUST OFFSHORE BY LATE SUN...BEFORE FINALLY LIFTING INLAND AND NORTHWARD AT THE SAME TIME SUN NIGHT. WINDS WILL VEER TO THE E THEN SE BY LATE SUN. THE SFC PG WILL FURTHER TIGHTEN AND COULD SEE WINDS AGAIN REACH SCEC/SCA THRESHOLDS. THE ONSHORE FLOW WILL CAPITALIZE ON A DECENT FETCH RESULTING IN SIGNIFICANT SEAS BUILDING FROM LATE SAT THRU SUN NIGHT...AND LIKELY REACHING SCA THRESHOLDS. LONG TERM /MONDAY THROUGH TUESDAY/... AS OF 300 AM FRIDAY...COULD ARGUE THAT A SFC WARM FRONT WILL HAVE PUSHED NORTHEAST OF THE LOCAL ILM WATERS COME MONDAY MORNING. THUS THE STRONG SE-S WINDS WILL VEER TO THE SW AT REDUCED SPEEDS AS THE SFC PG RELAXES SOME. THIS WILL BE SHORT-LIVED AS THE GRADIENT ROOTEDNESS AGAIN AHEAD OF THE APPROACHING COLD FRONT...WHICH IS PROGGED TO PUSH ACROSS THE LOCAL WATERS BY DAYBREAK TUE. WINDS OVER THE WATERS WILL FURTHER VEER TO THE W-NW AS RIDGING FROM WEAK SFC HIGH CENTERED OVER THE GULF COAST STATES AFFECTS THE LOCAL WATERS ON TUESDAY. MODELS NOW INDICATE A SECONDARY SFC COLD FRONT OR SFC TROF TO PUSH ACROSS THE LOCAL WATERS TUE NIGHT...WHICH WILL FURTHER VEER THE WINDS TO THE NW-N. SCEC OR SCA THRESHOLDS WILL REMAIN POSSIBLE AT THE START OF THIS PERIOD...FADING QUICKLY BY LATE TUE NIGHT. SIGNIFICANT SEAS WILL PEAK DURING MONDAY...THAN WILL INDICATE A SUBSIDING TREND THERE- AFTER AS WINDS VEER TO EVENTUALLY AN OFFSHORE TRAJECTORY BY LATE TUE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR AMZ250- 252. && $$ SYNOPSIS...SHK NEAR TERM...SHK SHORT TERM...DCH LONG TERM...DCH AVIATION...HDL
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
542 AM MDT FRI APR 17 2015 .SHORT TERM...TODAY THROUGH SATURDAY NIGHT ISSUED AT 352 AM MDT FRI APR 17 2015 CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER THE OKLAHOMA PANHANDLE AREA RIGHT NOW...WITH WEAK HIGH PRESSURE OVER EASTERN MT INTO WESTERN ND. UPPER LEVEL ANALYSIS SHOWS LARGE LOW PRESSURE SYSTEM CENTERED OVER THE FOUR CORNERS AREA...WITH STRONG JET WRAPPING AROUND THE SOUTHERN AND EASTERN SIDES OF THE LOW. CLOUD SHIELD TO THE NORTH AND EAST OF THE SYSTEM IS PUSHING NORTHWARD INTO SOUTHERN PARTS OF THE CWA...BUT DRYING UP AS IT MOVES INTO VERY DRY AIRMASS OVER NORTHERN PORTIONS OF THE NORTHERN PLAINS RIGHT NOW. REGIONAL RADARS SHOWING SHOWERS MOVING WEST-NORTHWEST ACROSS MUCH OF WESTERN NEB INTO SOUTHEAST WY...WITH DRY CONDITIONS PREVAILING ACROSS OUR CWA AT THE MOMENT. TEMPS CURRENTLY RANGE FROM THE LOW TO MID 30S ACROSS PORTIONS OF NORTHEAST WY...THE BLACK HILLS...AND FAR NORTHWEST SD...TO THE UPPER 40S ACROSS SOUTH CENTRAL SD. WINDS ARE VARIABLE AT LESS THAN 10 MPH. THE SYSTEM OVER THE FOUR CORNERS AREA EARLY THIS MORNING WILL MOVE SLOWLY NORTHEASTWARD ACROSS SOUTHERN AND EASTERN CO OVER THE NEXT COUPLE OF DAYS AND THEN ACCELERATE EASTWARD ACROSS THE CENTRAL PLAINS SATURDAY NIGHT INTO SUNDAY. THE EXACT TRACK AND TIMING OF THE SYSTEM IS STILL UNCERTAIN AT THIS POINT AND WILL ULTIMATELY HELP DETERMINE HOW MUCH PCPN WE GET ACROSS THE AREA...ESPECIALLY NORTHERN AND WESTERN PORTIONS OF THE CWA...WHERE AMOUNTS OF VERY LITTLE TO A HALF INCH OR MORE ARE POSSIBLE DEPENDING ON THE TRACK. ALL THE 00Z SHORT RANGE MODELS SHOW MOST OR ALL OF THE CWA RECEIVING AT LEAST A LITTLE BIT OF RAINFALL...WITH THE HIGHEST AMOUNTS GENERALLY OVER FAR SOUTHWEST INTO SOUTH CENTRAL SD. THE 00Z GFS SHOWS THE HEAVIEST PCPN FURTHER EAST TOWARD CENTRAL SD...WHILE THE OTHER MODELS GENERALLY HAVE IT OVER FAR SOUTHWEST/SOUTHERN SD. WILL LEAN THE FORECAST MORE TOWARD THE CONSENSUS AT THIS POINT AND KEEP HEAVIER PCPN AMOUNTS OVER FAR SOUTHERN SD. FORECAST CONFIDENCE IS HIGHEST RIGHT NOW ON SOUTHERN PORTIONS OF THE CWA RECEIVING THE MOST RAINFALL...AS WELL AS THE BEST CHANCES FOR RAINFALL ACROSS THE CWA BEING LATER TONIGHT INTO SATURDAY EVENING. PROJECTED RAINFALL AMOUNTS ACROSS THE CWA WILL MOSTLY BE IN THE 0.25 TO 0.75 INCH RANGE...WITH LESSER AMOUNTS LIKELY OVER FAR NORTHWESTERN PORTIONS OF THE CWA AND POSSIBLY AN INCH OR MORE OVER FAR SOUTHWEST INTO SOUTH CENTRAL SD. HOWEVER...WOULD TEND TO LEAN MORE TOWARD THE LIGHTER AMOUNTS FOR MOST AREAS AS HAS BEEN THE CASE FOR SYSTEMS OF LATE. FOR TODAY...SKIES WILL STAY MOSTLY CLOUDY ACROSS FAR SOUTHERN PORTIONS OF THE CWA...WITH CLOUDS GRADUALLY INCREASING TO THE NORTH. WITH MORE SUNSHINE...TEMPS THIS AFTERNOON WILL BE HIGHEST OVER FAR NORTHERN AND EASTERN PORTIONS OF THE CWA...WITH HIGHS RANGING FROM THE 50S OVER THE BLACK HILLS AND FAR SOUTHWEST SD TO THE MID TO UPPER 60S OVER FAR NORTHWEST INTO CENTRAL SD. WINDS WILL BECOME EAST TO NORTHEAST IN MOST AREAS BY THE AFTERNOON. CHANCES FOR SHOWERS WILL MAINLY BE CONFINED TO SOUTHERN SD TODAY...WITH THE BEST CHANCES IN THE AFTERNOON. CAN NOT RULE OUT A THUNDERSTORM OR TWO ACROSS SOUTHERN AREAS AS WELL THIS AFTERNOON. AS THE UPPER LOW MOVES ACROSS CO TONIGHT AND SATURDAY...LOW LEVEL MOISTURE AND UPPER LEVEL ENERGY WILL EXPAND NORTHWARD INTO THE NORTHERN PLAINS...ESPECIALLY LATER TONIGHT AND SATURDAY. SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED ACROSS THE AREA. THE MOST WIDESPREAD COVERAGE OF SHOWERS SHOULD BE ON SATURDAY...SO WILL GO WITH LIKELY POPS ACROSS MOST OF THE CWA. WITH THE LOW STAYING FAR ENOUGH SOUTH OF THE CWA...TEMPS WILL STAY WARM ENOUGH FOR MOSTLY RAIN ACROSS EVEN THE BLACK HILLS...BUT COULD SEE A MIX OVER THE HIGHEST ELEVATIONS...MAINLY LATE TONIGHT/EARLY SATURDAY AND THEN SATURDAY NIGHT WHEN THE SYSTEM EXITS. A COLD FRONT WILL TRACK ACROSS THE CWA LATE SATURDAY AND SATURDAY NIGHT...HELPING TO PUSH THE SYSTEM OUT OF THE REGION...BUT WILL BRING GUSTY WINDS ACROSS THE AREA INTO SUNDAY. .LONG TERM...SUNDAY THROUGH THURSDAY ISSUED AT 352 AM MDT FRI APR 17 2015 BLOCKED FLOW TO DEVELOP OVER THE WESTERN ATLANTIC AND EASTERN NOAM...WHICH WILL SET THE STAGE FOR WESTERN NOAM RIDING AND POTENTIAL REX TYPE BLOCKING OVER THE WESTERN CONUS. THIS WILL SUPPORT A LOW CONFIDENCE FLOW REGIME AS FORECAST MODELS WILL CONTINUALLY ADJUST TO THE LATEST OBS GIVEN TYPICAL POOR MODEL PERFORMANCE IN THESE PATTERNS. GENERALLY DRY CONDS CAN BE EXPECTED GIVEN THE REGION/S PROXY TO THE EASTERN NOAM UPPER TROUGH. A WEAK SIGNAL FOR PRECIP DOES REMAIN TOWARD THE END OF THE PERIOD WHEN FORECAST MODELS TRY TO ADVECT A WANDERING UPPER TROUGH EAST. HOWEVER...AS ALREADY STATED...LOW CONFIDENCE PER FLOW DETAILS LENDS ONLY A 20 POP AT BEST...WITH DRY THE LIKELY SCENARIO GIVEN THE PATTERN. GIVEN STRONG INFLUENCE EXPECTED OF THE EVENTUAL EASTERN CONUS UPPER LOW...EXPECT TEMPS TO BE NEAR OR SLIGHTLY BELOW SEASONAL NORMS IN THE MAJORITY OF THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 538 AM MDT FRI APR 17 2015 VFR CONDS WILL PREVAIL MOST PLACES IN THE PERIOD. A SLOW MOVING UPPER LOW WILL SLIDE NE AND BRING MVFR CONDS IN RAIN TO MAINLY EXTREME SW SD TODAY. MVFR CONDS WILL SPREAD NORTH TONIGHT...AFFECTING THE RAP TERMINAL BY LATE IN THE PERIOD...WITH SCT IFR CIGS POSSIBLE IN THE BLACK HILLS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...26 LONG TERM...JC AVIATION...JC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
604 AM CDT FRI APR 17 2015 UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND SATURDAY ISSUED AT 400 AM CDT FRI APR 17 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK COLD FRONT SLOWLY MOVING TO THE SOUTHEAST OVER FAR NORTHWEST WISCONSIN. AHEAD OF THE FRONT...AREAS OF BROKEN MID-CLOUDS ARE MOVING TO THE EAST OVER CENTRAL AND NORTHERN WISCONSIN. CLEAR SKIES EXIST BEHIND THIS FRONT OVER THE NORTHERN PLAINS. MEANWHILE...SHOWERS AND THUNDERSTORMS ARE OCCURRING OVER THE CENTRAL PLAINS AHEAD OF AN UPPER LOW SPINNING OVER THE 4 CORNERS REGION. FORECAST CONCERNS INCLUDE HIGH TEMPS AND LOW HUMIDITIES FOR SATURDAY. TODAY...THE COLD FRONT WILL SLOW AS IT WEAKENS OVER THE NORTHWEST THIRD OF THE STATE. SCATTERED TO BROKEN MID-LEVEL CLOUD DECK WILL GRADUALLY DISSIPATE THROUGH THE MORNING AS SUBSIDENCE STRENGTHENS OVERHEAD. WILL STILL BE SOME RESIDUAL MOISTURE LEFT AROUND 800MB...HOWEVER...THAT WILL TURN INTO A CU FIELD BY LATE MORNING OVER CENTRAL TO NORTHEAST WISCONSIN. FAR NORTHERN WISCONSIN WILL SEE AN INFLUX OF DRIER AIR DURING THE AFTERNOON...WHICH WILL DROP HUMIDITIES INTO THE 20 TO 25 PCT RANGE. HUMIDITIES SHOULD BE ABOVE CRITICAL CRITERIA ELSEWHERE. RAISED HIGH TEMPS BASED ON 925MB TEMPS ON THE BETTER PERFORMING NAM AND ECMWF...AND MAY NOT BE HIGH ENOUGH. TEMPS TO MAX OUT TO NEAR 70 NORTH TO THE UPPER 70S IN THE WARM SPOTS. TONIGHT...THE WEAKENING FRONT WILL DROP ACROSS CENTRAL AND NORTHEAST WISCONSIN DURING THE EVENING WHILE A SECONDARY AND MORE POTENT FRONT QUICKLY MOVES SOUTH ACROSS NORTHERN AND CENTRAL WISCONSIN AFTER MIDNIGHT. BEHIND THE SECOND FRONT...WINDS WILL SHIFT TO THE NORTHEAST AND COULD GUST FOR A COUPLE HOURS TO 20 OR 25 MPH. TEMPS WILL ALSO COOL OFF QUICKLY BEHIND THE FRONT WITH LOWS FALLING INTO THE MIDDLE 30S NORTH TO THE MIDDLE 40S SOUTH. SATURDAY...CANADIAN HIGH PRESSURE WILL BUILD SOUTHEAST ACROSS THE CENTRAL GREAT LAKES. THE AIRMASS ASSOCIATED WITH THIS SURFACE HIGH IS EXCEPTIONALLY DRY (NAM 850-700MB RH FALLS TO 2 PCT!). THOUGH HIGH CLOUDS WILL BE ON THE INCREASE DURING THE AFTERNOON AHEAD OF THE CENTRAL ROCKIES UPPER LOW...SHOULD STILL SEE PLENTY OF SUNSHINE ALBEIT WITH COOLER TEMPERATURES. CRITICAL RELATIVE HUMIDITIES BETWEEN 15 TO 25 PCT WILL STILL OCCUR THOUGH NORTH AND WEST OF THE FOX VALLEY. POTENTIAL IS THERE FOR HUMIDITIES TO FALL LOWER THAN THIS IF TAPPING OCCURS INTO THIS BONE DRY AIR ALOFT. HIGHS MAINLY IN THE LOW TO MID 60S AWAY FROM LAKE MICHIGAN. .LONG TERM...SATURDAY NIGHT THROUGH THURSDAY ISSUED AT 400 AM CDT FRI APR 17 2015 500MB OPEN TROUGH WILL EVOLVE INTO A CLOSED LOW OVER THE WESTERN GREAT LAKES REGION BY EARLY NEXT WEEK. COOL CYCLONIC FLOW WILL CONTINUE FOR THE REMAINDER OF NEXT WEEK AS THE 500MB LOW MEANDERS ACROSS THE GREAT LAKES REGION/EASTERN CANADA. MODELS IN SOMEWHAT BETTER AGREEMENT TONIGHT BRINGING THE BEST CHANCE FOR RAIN SUNDAY INTO SUNDAY NIGHT. WILL CONTINUE A SMALL CHANCE OF SHOWERS AFTER MIDNIGHT ON SATURDAY NIGHT TO ACCOUNT FOR A SLIGHTLY QUICKER ARRIVAL THAT SOME OF THE MODELS ARE DEPICTING. WILL HAVE LIKELY OR LOW END CATEGORICAL CHANCES FOR RAIN ON SUNDAY. HIGH TEMPERATURES TRICKY DEPENDING ON QUICK THE STEADIER RAINS ARRIVE. IF RAIN ARRIVES EARLY IN THE DAY SUNDAY...HIGH TEMPERATURES WILL NEED TO BE LOWERED. COUNTING ON SOME DRY ON BACKSIDE OF THE RETREATING HIGH PRESSURE SYSTEM TO SLOW THE ARRIVAL OF THE RAIN ACROSS EASTERN WISCONSIN. OTHERWISE...BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE WEEK WITH CHANCES OF RAIN INTO THE MIDDLE OF NEXT WEEK. STILL HAVE A CHANCE OF SNOW LATE AT NIGHT OR EARLY IN THE DAY FOR EACH PERIOD FROM MONDAY NIGHT THROUGH WEDNESDAY. BY THURSDAY...UPPER LOW MAY BE FAR ENOUGH AWAY FOR JUST A SMALL CHANCE OF RAIN ACROSS THE FAR NORTH. PREVIOUS FORECAST TEMPERATURES SEEMED REASONABLE WITH ONLY MINOR CHANGES MADE IN SOME PERIODS. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 604 AM CDT FRI APR 17 2015 VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. SCATTERED TO BROKEN MID-LEVEL CLOUDS WILL DEPART THIS MORNING...WHICH WILL LEAVE CLEAR CONDITIONS THROUGH TONIGHT. A DRY COLD FRONT WILL ARRIVE AFTER MIDNIGHT. WINDS WILL SHIFT TO THE NORTHEAST BEHIND THE FRONT...AND BECOME GUSTY FOR A FEW HOURS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
933 AM PDT Fri Apr 17 2015 .Synopsis... Warm weekend then cooling trend into mid week. A weak weather system will bring a slight chance of mountain showers and thunderstorms this weekend into Monday. A cold upper level trough moves into the area by mid week bringing cooler temperatures and a chance of precipitation over all of interior Northern California. && .Discussion... Cooler morning in the Valley with light winds and mountains warmer with a warmer air mass. Temperatures this afternoon will rise into the mid 80s in the Valley and low 50s to low 70s in the mountains which is about 10 to 15 degrees above normal for mid April. Temperatures warm up a little more on Saturday with high in the mid 80s to around 90 in the Valley and mid 50s to mid 70s in the mountains. Similar temperatures are expected on Sunday then a little cooler temperatures on Monday as trough approaches the area and onshore flow increases. Air temperatures are warm but water temperatures in rivers and lakes remains cold in the low 40s to low 60s. People going in the rivers and lakes this weekend should use caution since cold water can lead to hypothermia. A weak disturbance moves into Northern California on Saturday then forms a weak upper level low off the Nor Cal coast late Saturday into Sunday. This will bring some instability for a slight chance of showers and thunderstorms over the mountains of interior Northern California on Saturday and Sunday, mainly in the afternoons and evenings. The best chance on Sunday looks like it will be over the Sierra as the disturbance moves southwest. Upper level trough trough digs offshore of the West Coast on Monday for continued instability over the mountains for a slight chance of showers and thunderstorms. .Extended Discussion (Tuesday through Friday) Mid range models zeroing in on idea of bringing weak Pacific trough onto the coast around Tuesday although ECMWF and GEM still have trough axis slightly offshore Tuesday afternoon. Rather limited moisture with this system will limit precipitation mainly to the mountain areas. GFS shows enough instability with this system Tuesday afternoon to warrant slight thunderstorm threat as well. Models all now pretty much centering the upper trough over the west coast by Wednesday morning so entire CWA has at least a slight threat of showers throughout the day Wednesday. GFS shows most of the instability has moved into Nevada by Wednesday but still somewhat borderline over central California so may need to readdress thunderstorm threat for Wednesday as we get closer. Weather change that appears fairly certain is the significant cool off expected Tuesday and Wednesday. Forecast highs between Monday and Wednesday showing a drop of anywhere from 15 to 20 degrees so this change will be quite noticeable with highs dropping to around normal for this time of year by mid week. Models vary a bit on positioning of low/trough on Thursday but whichever solution verifies...cyclonic flow over the region should continue the shower threat CWA wide. Extended models showing a transition to northerly flow aloft over the north state by Friday as upper system shifts into the Great Basin. As a result...shower threat shifts eastward with main precipitation threat from RAP around moisture over the Sierra. Daytime temperatures rebound a bit but still close to normal compared to very warm temperatures expected early in the week. && .Aviation... VFR conditions next 24 hours. Isolated thunderstorms possible over the mountains after 18z Saturday. Winds generally below 15 knots except in vicinity of thunderstorms. && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1107 AM MDT FRI APR 17 2015 .UPDATE... ISSUED AT 1010 AM MDT FRI APR 17 2015 THE UPPER LOW OVER THE SW QUAD OF THE STATE IS CONTINUING TO SWEEP HEAVY SNOWFALL BACK INTO THE LAKE AND CHAFFEE COUNTY AREAS...AS PER LATEST SATELLITE IMAGERY AND SPOTTER REPORTS. THEREFORE...UPGRADED EXISTING SNOW ADVISORIES FOR LOWER PORTIONS OF LAKE AND CHAFFEE COUNTIES TO A WINTER STORM WARNING...IN EFFECT UNTIL 12Z TOMORROW MORNING. MOORE && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 410 AM MDT FRI APR 17 2015 THERE ARE SEVERAL CONCERNS FOR THE SHORT TERM FORECAST...INCLUDING THE POTENTIAL FOR CRITICAL FIRE WX CONDITIONS...THE POTENTIAL FOR SEVERE STORMS AND SNOW AMOUNTS. STILL SEE OCNL LIGHTNING STRIKES OVR SERN CO THIS MORNING. SATELLITE IMAGES SHOW THE UPR LOW CENTERED OVR NWRN NM THIS MORNING...AND IT IS FORECAST TO MOVE NORTHEASTWARD TODAY AND TONIGHT. BY 12Z SAT...THE NAM...GFS AND ECMWF SHOW THE LOW CENTER IN DIFFERENT LOCATIONS. THE GFS AND ECMWF ARE FAIRLY SIMILAR WITH THE LOW ABOUT OVR THE PALMER DVD...THE GFS IS A LITTLE FARTHER E AND S THAN THE ECMWF. THE NAM HAS THE LOW CENTER AT 12Z SAT OVR NRN SAGUACHE COUNTY. FOR THE FIRST HALF OF TODAY THE MODELS SHOW CONTINUED MOIST EASTERLY FLOW ACRS THE PIKES PEAK REGION...FREMONT COUNTY AND LAKE AND CHAFFEE COUNTIES...WITH SOME PCPN ALSO OVR THE SW MTNS AND SRN PORTIONS OF THE ERN MTNS...JUST NOT AS HEAVY AS NRN AREAS. AT THE SAME TIME...A DRY SLOT WL WORK ITS WAY INTO THE SERN PLAINS. HOWEVER...THE NAM HAS AN AREA OF CONVECTION DEVELOPING...MAINLY N OF HIGHWAY 50 OVR THE ERN PLAINS THIS AFTERNOON...WITH LAS ANIMAS AND BACA COUNTIES REMAINING DRY. THE GFS AND HRRR ARE DRY THIS AFTERNOON OVR THE FAR SERN PLAINS. STRONG SOUTHERLY WINDS OVR BACA AND LAS ANIMAS COUNTIES...ALONG WITH RH VALUES DROPPING BELOW 15 PERCENT ARE EXPECTED THIS AFTERNOON SO WL ISSUE A RED FLAG WARNING FOR THESE LOCATIONS. PORTIONS OF SRN PROWERS AND BENT COUNTIES MAY ALSO REACH RED FLAG CRITERIA...BUT UNCERTAINTY ABOUT PCPN OVR THESE COUNTIES WL KEEP ME FROM ISSUING A FIRE HIGHLIGHT AT THIS TIME. THE NAM DECREASES PCPN OVR MANY OF THE MTN AREAS THIS AFTERNOON...WHILE IT STILL LOOKS GOOD ON THE GFS OVR THE NRN MTNS PORTIONS OF THE CWA. THE ECMWF DECREASES PCPN OVR THE PIKES PEAK REGION BUT KEEPS GOOD PCPN GOING OVR LAKE AND CHAFFEE COUNTIES. THE GFS IS MUCH DRIER AT THE SFC THIS AFTERNOON OVR THE FAR SERN PLAINS THAN THE NAM...WHICH MAKES A DIFFERENCE IN THE POTENTIAL FOR SEVERE WX. WL LEAN THE FORECAST A LITTLE MORE TOWARD THE NAM OVR PROWERS...BENT...AND KIOWA COUNTIES. IF THE NAM IS CORRECT...CAPE VALUES COULD RANGE FROM ABOUT 600-1500 J/KG OVR PROWERS...NRN BENT AND KIOWA COUNTIES...WITH 0-6KM SHEAR VALUES OF 50-60 KTS...AND WE COULD SEE A COUPLE SEVERE STORMS. THE HRRR ALSO SETS UP A DRYLINE MAINLY NORTH OF HIGHWAY 50S THIS AFTERNOON OVR THE FAR SERN PLAINS. HOWEVER...IF THE DRIER GFS IS CORRECT THE BETTER MSTR AND SVR CHANCES WL BE EAST OF THE AREA. TONIGHT AS THE UPR LOW CONTINUES TO LIFT NORTHEASTWARD...MUCH OF THE SERN PLAINS LOOK TO BE DRY...WITH MANY OF THE MTN AREAS STILL SEEING SOME PCPN. ALTHOUGH THE DIFFERING POSITIONS OF THE UPR LOW CENTER RESULT IN DIFFERENCES IN WHAT MTNS AREAS WL HAVE THE BEST PCPN CHANCES. WILL NOT MAKE ANY CHANGES TO THE WINTER WEATHER HIGHLIGHTS THIS MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 410 AM MDT FRI APR 17 2015 SATURDAY-SUNDAY...LATEST MODELS REMAIN IN DECENT AGREEMENT OF STRONG UPPER LOW ACROSS SOUTH CENTRAL COLORADO EARLY SATURDAY SLOWLY LIFTING NORTH AND EAST THROUGH SATURDAY NIGHT WITH THE SYSTEM THEN WEAKENING AND MERGING WITH A BROAD UPPER TROUGH TRANSLATING ACROSS THE NORTHERN TIER OF STATES. BEST CHANCES OF PRECIPITATION EARLY SATURDAY REMAINS ACROSS THE CONTDVD THROUGH THE SOUTHERN MTS WITH DEVELOPING WRAPAROUND PRECIPITATION SHIELD AND DEVELOPING NORTHWEST FLOW BEHIND THE PASSING SYSTEM. SHOULD SEE ISOLATED TO SCATTERED SHOWERS AND A FEW EMBEDDED THUNDERSTORMS ACROSS THE EASTERN PLAINS SATURDAY AFTERNOON AND EVENING WITH COLD CORE UPPER LOW TRANSLATING INTO NORTHEASTERN COLORADO. MAY NEED TO EXTEND OR ADD WINTER HIGHLIGHTS ACROSS THE CENTRAL MTS INTO SATURDAY WITH SEVERAL INCHES OF SNOW EXPECTED...ESPECIALLY AOA 10KT FEET. MID LEVEL TEMPS SLOWLY WARM SATURDAY AS THE SYSTEM LIFTS OUT ACROSS THE AREA AND SHOULD SEE HIGHS SLIGHTLY WARMER AS A RESULT...THOUGH STILL BELOW SEASONAL AVERAGES. PASSING UPPER SYSTEM ACROSS THE AREA LATE SATURDAY SENDS A COLD FRONT ACROSS THE EASTERN PLAINS EARLY SUNDAY MORNING...WITH GUSTY NORTH TO NORTHWEST WINDS OF 20 TO 40 MPH EXPECTED IN ITS WAKE...WITH THE STRONGEST WINDS EXPECTED ACROSS THE FAR EASTERN PLAINS. A MINOR WAVE EMBEDDED WITHIN THE NORTHWEST FLOW ALOFT SUPPORTS ISOLATED TO SCATTERED SHOWERS ACROSS THE AREA ON SUNDAY...WITH TEMPERATURES SLIGHTLY COOLER THAN SATURDAY. MONDAY-TUESDAY...EMBEDDED DISTURBANCES IN THE SLOWLY MODERATING NORTHWEST FLOW ACROSS THE AREA WILL KEEP ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS IN THE FORECAST WITH TEMPERATURES WARMING BACK TO NEAR SEASONAL AVERAGES. WEDNESDAY-THURSDAY...A REX LIKE BLOCKING PATTERN LOOKS TO SET UP ACROSS THE REGION WITH RIDGING ACROSS THE ROCKIES AND TROUGHS SETTING UP OVER THE COASTS. THIS LOOKS TO KEEP UNSETTLED WEATHER ACROSS THE AREA WITH COOL HIGH PRESSURE ACROSS THE MIDWEST KEEPING UPSLOPE FLOW IN PLACE ACROSS EASTERN COLORADO ALONG WITH INCREASING MOISTURE WITHIN DEVELOPING SOUTHWEST FLOW ALOFT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1102 AM MDT FRI APR 17 2015 DRY AIR IS SPREADING ACROSS SOUTHERN AND EASTERN PORTIONS OF COLORADO RESULTING IN VFR CONDITIONS AT ALL THREE TAF SITES. MEANWHILE...WRAPPED UP INTENSE UPPER LOW WILL KEEP IFR TO LIFR AND HEAVY SNOW CONTINUING ACROSS THE CENTRAL MTS. GENERALLY SOUTHERLY WINDS CAN BE EXPECTED AT THE TAF SITES TODAY...THOUGH SHOWERS MAY SPREAD OFF THE MOUNTAINS INTO THE KCOS TAF SITE DURING THE AFTERNOON. IF THEY AFFECT THE TERMINAL...THEY SHOULD BE SHORT LIVED AND GIVEN THE ANTICIPATED SPOTTY NATURE...KCOS TAF WILL CARRY VCSH IN THE LATE AFTN/EARLY EVENING HOURS. WINDS WILL SHIFT OUT OF THE NORTH LATER TONIGHT FOR KCOS AND KPUB TAF SITES WITH WINDS GENERALLY UNDER 15 KTS. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058>063-072- 073-080-082. WINTER WEATHER ADVISORY UNTIL 6 PM MDT THIS EVENING FOR COZ077>079-084. RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ233-237. WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ076-081. WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ074-075. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ066. && $$ UPDATE...MOORE SHORT TERM...28 LONG TERM...MW AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1014 AM MDT FRI APR 17 2015 .UPDATE... ISSUED AT 1010 AM MDT FRI APR 17 2015 THE UPPER LOW OVER THE SW QUAD OF THE STATE IS CONTINUING TO SWEEP HEAVY SNOWFALL BACK INTO THE LAKE AND CHAFFEE COUNTY AREAS...AS PER LATEST SATELLITE IMAGERY AND SPOTTER REPORTS. THEREFORE...UPGRADED EXISTING SNOW ADVISORIES FOR LOWER PORTIONS OF LAKE AND CHAFFEE COUNTIES TO A WINTER STORM WARNING...IN EFFECT UNTIL 12Z TOMORROW MORNING. MOORE && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 410 AM MDT FRI APR 17 2015 THERE ARE SEVERAL CONCERNS FOR THE SHORT TERM FORECAST...INCLUDING THE POTENTIAL FOR CRITICAL FIRE WX CONDITIONS...THE POTENTIAL FOR SEVERE STORMS AND SNOW AMOUNTS. STILL SEE OCNL LIGHTNING STRIKES OVR SERN CO THIS MORNING. SATELLITE IMAGES SHOW THE UPR LOW CENTERED OVR NWRN NM THIS MORNING...AND IT IS FORECAST TO MOVE NORTHEASTWARD TODAY AND TONIGHT. BY 12Z SAT...THE NAM...GFS AND ECMWF SHOW THE LOW CENTER IN DIFFERENT LOCATIONS. THE GFS AND ECMWF ARE FAIRLY SIMILAR WITH THE LOW ABOUT OVR THE PALMER DVD...THE GFS IS A LITTLE FARTHER E AND S THAN THE ECMWF. THE NAM HAS THE LOW CENTER AT 12Z SAT OVR NRN SAGUACHE COUNTY. FOR THE FIRST HALF OF TODAY THE MODELS SHOW CONTINUED MOIST EASTERLY FLOW ACRS THE PIKES PEAK REGION...FREMONT COUNTY AND LAKE AND CHAFFEE COUNTIES...WITH SOME PCPN ALSO OVR THE SW MTNS AND SRN PORTIONS OF THE ERN MTNS...JUST NOT AS HEAVY AS NRN AREAS. AT THE SAME TIME...A DRY SLOT WL WORK ITS WAY INTO THE SERN PLAINS. HOWEVER...THE NAM HAS AN AREA OF CONVECTION DEVELOPING...MAINLY N OF HIGHWAY 50 OVR THE ERN PLAINS THIS AFTERNOON...WITH LAS ANIMAS AND BACA COUNTIES REMAINING DRY. THE GFS AND HRRR ARE DRY THIS AFTERNOON OVR THE FAR SERN PLAINS. STRONG SOUTHERLY WINDS OVR BACA AND LAS ANIMAS COUNTIES...ALONG WITH RH VALUES DROPPING BELOW 15 PERCENT ARE EXPECTED THIS AFTERNOON SO WL ISSUE A RED FLAG WARNING FOR THESE LOCATIONS. PORTIONS OF SRN PROWERS AND BENT COUNTIES MAY ALSO REACH RED FLAG CRITERIA...BUT UNCERTAINTY ABOUT PCPN OVR THESE COUNTIES WL KEEP ME FROM ISSUING A FIRE HIGHLIGHT AT THIS TIME. THE NAM DECREASES PCPN OVR MANY OF THE MTN AREAS THIS AFTERNOON...WHILE IT STILL LOOKS GOOD ON THE GFS OVR THE NRN MTNS PORTIONS OF THE CWA. THE ECMWF DECREASES PCPN OVR THE PIKES PEAK REGION BUT KEEPS GOOD PCPN GOING OVR LAKE AND CHAFFEE COUNTIES. THE GFS IS MUCH DRIER AT THE SFC THIS AFTERNOON OVR THE FAR SERN PLAINS THAN THE NAM...WHICH MAKES A DIFFERENCE IN THE POTENTIAL FOR SEVERE WX. WL LEAN THE FORECAST A LITTLE MORE TOWARD THE NAM OVR PROWERS...BENT...AND KIOWA COUNTIES. IF THE NAM IS CORRECT...CAPE VALUES COULD RANGE FROM ABOUT 600-1500 J/KG OVR PROWERS...NRN BENT AND KIOWA COUNTIES...WITH 0-6KM SHEAR VALUES OF 50-60 KTS...AND WE COULD SEE A COUPLE SEVERE STORMS. THE HRRR ALSO SETS UP A DRYLINE MAINLY NORTH OF HIGHWAY 50S THIS AFTERNOON OVR THE FAR SERN PLAINS. HOWEVER...IF THE DRIER GFS IS CORRECT THE BETTER MSTR AND SVR CHANCES WL BE EAST OF THE AREA. TONIGHT AS THE UPR LOW CONTINUES TO LIFT NORTHEASTWARD...MUCH OF THE SERN PLAINS LOOK TO BE DRY...WITH MANY OF THE MTN AREAS STILL SEEING SOME PCPN. ALTHOUGH THE DIFFERING POSITIONS OF THE UPR LOW CENTER RESULT IN DIFFERENCES IN WHAT MTNS AREAS WL HAVE THE BEST PCPN CHANCES. WILL NOT MAKE ANY CHANGES TO THE WINTER WEATHER HIGHLIGHTS THIS MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 410 AM MDT FRI APR 17 2015 SATURDAY-SUNDAY...LATEST MODELS REMAIN IN DECENT AGREEMENT OF STRONG UPPER LOW ACROSS SOUTH CENTRAL COLORADO EARLY SATURDAY SLOWLY LIFTING NORTH AND EAST THROUGH SATURDAY NIGHT WITH THE SYSTEM THEN WEAKENING AND MERGING WITH A BROAD UPPER TROUGH TRANSLATING ACROSS THE NORTHERN TIER OF STATES. BEST CHANCES OF PRECIPITATION EARLY SATURDAY REMAINS ACROSS THE CONTDVD THROUGH THE SOUTHERN MTS WITH DEVELOPING WRAPAROUND PRECIPITATION SHIELD AND DEVELOPING NORTHWEST FLOW BEHIND THE PASSING SYSTEM. SHOULD SEE ISOLATED TO SCATTERED SHOWERS AND A FEW EMBEDDED THUNDERSTORMS ACROSS THE EASTERN PLAINS SATURDAY AFTERNOON AND EVENING WITH COLD CORE UPPER LOW TRANSLATING INTO NORTHEASTERN COLORADO. MAY NEED TO EXTEND OR ADD WINTER HIGHLIGHTS ACROSS THE CENTRAL MTS INTO SATURDAY WITH SEVERAL INCHES OF SNOW EXPECTED...ESPECIALLY AOA 10KT FEET. MID LEVEL TEMPS SLOWLY WARM SATURDAY AS THE SYSTEM LIFTS OUT ACROSS THE AREA AND SHOULD SEE HIGHS SLIGHTLY WARMER AS A RESULT...THOUGH STILL BELOW SEASONAL AVERAGES. PASSING UPPER SYSTEM ACROSS THE AREA LATE SATURDAY SENDS A COLD FRONT ACROSS THE EASTERN PLAINS EARLY SUNDAY MORNING...WITH GUSTY NORTH TO NORTHWEST WINDS OF 20 TO 40 MPH EXPECTED IN ITS WAKE...WITH THE STRONGEST WINDS EXPECTED ACROSS THE FAR EASTERN PLAINS. A MINOR WAVE EMBEDDED WITHIN THE NORTHWEST FLOW ALOFT SUPPORTS ISOLATED TO SCATTERED SHOWERS ACROSS THE AREA ON SUNDAY...WITH TEMPERATURES SLIGHTLY COOLER THAN SATURDAY. MONDAY-TUESDAY...EMBEDDED DISTURBANCES IN THE SLOWLY MODERATING NORTHWEST FLOW ACROSS THE AREA WILL KEEP ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS IN THE FORECAST WITH TEMPERATURES WARMING BACK TO NEAR SEASONAL AVERAGES. WEDNESDAY-THURSDAY...A REX LIKE BLOCKING PATTERN LOOKS TO SET UP ACROSS THE REGION WITH RIDGING ACROSS THE ROCKIES AND TROUGHS SETTING UP OVER THE COASTS. THIS LOOKS TO KEEP UNSETTLED WEATHER ACROSS THE AREA WITH COOL HIGH PRESSURE ACROSS THE MIDWEST KEEPING UPSLOPE FLOW IN PLACE ACROSS EASTERN COLORADO ALONG WITH INCREASING MOISTURE WITHIN DEVELOPING SOUTHWEST FLOW ALOFT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 410 AM MDT FRI APR 17 2015 KCOS WL MAINLY HAVE MVFR CONDITIONS THIS MORNING WITH THE POTENTIAL FOR SNOW SHOWERS OR A MIX OF RAIN AND SNOW. THIS AFTERNOON FORECAST SOUNDINGS SHOW A RETURN TO VFR CONDITIONS THROUGH EARLY EVENING...AND THEN THE POTENTIAL FOR MVFR CONDITIONS DEVELOPING AGAIN. KPUB SHOULD GENERALLY HAVE MVFR CONDITIONS WITH THE POTENTIAL FOR RAIN SHOWERS AND MAYBE EVEN A THUNDERSTORM. FORECAST SOUNDINGS SHOW A RETURN TO VFR CONDITIONS IN THE LATE MORNING HOURS AND THROUGH THE REST OF THE PERIOD. KALS SHOULD GENERALLY SEE VFR CONDITIONS UNTIL LATE TONIGHT...WHEN THERE WILL BE THE POTENTIAL FOR MVFR OR IFR CONDITIONS. BREEZY SOUTHWEST WINDS ARE EXPECTED THIS AFTERNOON. && .PUB WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058>063-072- 073-080-082. WINTER WEATHER ADVISORY UNTIL 6 PM MDT THIS EVENING FOR COZ077>079-084. RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ233-237. WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ076-081. WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ074-075. WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ066. && $$ UPDATE...MOORE SHORT TERM...28 LONG TERM...MW AVIATION...28
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1220 PM CDT FRI APR 17 2015 .UPDATE... ISSUED AT 1050 AM CDT FRI APR 17 2015 WEAK RIDGING OVER THE REGION KEEPING MILD WEATHER IN PLACE. QUICK MORNING WARM UP UNDER A MOSTLY SUNNY SKY AND TEMPS ON TRACK TO HEAD INTO THE UPPER 70S. ALTHOUGH CUMULUS CLOUDS ARE EXPECTED TO DEVELOP LATER THIS AFTERNOON...COVERAGE SHOULD BE LIGHTER IN THE NORTH THAN THE SOUTHERN TIER OF THE STATE...AND SHOULD NOT INTERFERE TOO MUCH WITH THE DIURNAL TREND UNDER SUCH LIGHT WINDS. FORECAST DOING WELL...HAVE ONLY MADE SOME MINOR ADJUSTMENTS. MAJOR UPDATES ARE NOT ANTICIPATED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 331 AM CDT FRI APR 17 2015 A DENSE FOG ADVISORY ISSUED AROUND 2 AM FOR EASTERN IL WILL BE ALLOWED TO CONTINUE THROUGH 9 AM CDT. THE PAST HOUR OR TWO THE DENSE FOG WITH VSBYS 1/4 MILE OR LESS HAS BEEN CONFINED TO AREAS EAST OF I- 57 AND COULD EXPAND FURTHER WEST OF I-57 WITH AREAS OF FOG AND PATCHY DENSE FOG AS FAR WEST AS I-55 PER HRRR MODEL UNTIL 9 AM. ONCE THE FOG LIFTS LATER THIS MORNING A NICE MILD SPRING DAY IS SHAPING UP ACROSS CENTRAL AND SOUTHEAST IL WITH WEAK HIGH PRESSURE OVER IN AND SOME UPPER LEVEL RIDGING INTO IL GIVING MOSTLY SUNNY SKIES AND LIGHT WINDS AND MILD HIGHS IN THE MID TO UPPER 70S. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 331 AM CDT FRI APR 17 2015 DRY CONDITIONS STILL EXPECTED TO CONTINUE ACROSS CENTRAL AND SOUTHEAST IL THROUGH AT LEAST SAT MORNING WITH JUST ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE DURING MID/LATE SAT AFTERNOON ALONG AND SW OF A GALESBURG TO LINCOLN TO LAWRENCEVILLE LINE. UPPER LEVEL RIDGE INTO THE OHIO RIVER VALLEY AND IL YET ON SATURDAY TO BRING ANOTHER MILD SPRING DAY IN THE MID TO UPPER 70S SATURDAY, WITH MILDEST READINGS NEAR THE IN BORDER WHERE MORE SUNSHINE EXPECTED. LARGE CUTOFF UPPER LEVEL LOW OVER COLORADO TONIGHT AND SATURDAY GETS ABSORBED BY NORTHERN STREAM CUTOFF LOW NORTH OF ND/MN SUNDAY AND MONDAY. WARM AIR ADVECTION SHOWERS AND SCATTERED THUNDERSTORMS TO SPREAD NE ACROSS CENTRAL AND SOUTHEAST IL DURING SATURDAY NIGHT ESPECIALLY AFTER MIDNIGHT AND CONTINUE SUNDAY. FAIRLY STRONG SURFACE LOW PRESSURE EJECTS NE FROM OK PANHANDLE TO NEAR CENTRAL IL BY SUNSET SUNDAY AND SWEEPS A COLD FRONT EAST THROUGH IL SUNDAY NIGHT. THIS TO LIKELY BRING MORE SHOWERS AND THUNDERSTORMS SUNDAY AND SUNDAY NIGHT AND SPC HAS MARGINAL RISK OF SEVERE STORMS SW OF I-74 SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING WITH SLIGHT RISK SW OF A PITTSFIELD TO EFFINGHAM TO LAWRENCEVILLE LINE FOR LARGE HAIL AND DAMAGING WIND GUSTS POSSIBLE. HIGHS SUNDAY MOSTLY IN THE LOWER 70S WITH SOME UPPER 60S NORTH OF I-74. A LARGE UPPER LEVEL TROF THEN DOMINATES THE MIDWEST MONDAY-THURSDAY AS STRONG CUTOFF LOW MOVES SLOWLY EAST ACROSS THE NORTHERN GREAT LAKES REGION. SHOWERS SHOULD DIMINISH TO WIDELY SCATTERED SHOWERS OVER CENTRAL IL ON MONDAY WITH BEST CHANCES OF SHOWERS OVER IN AND NORTHERN IL. COOLER HIGHS OF 60-65F MONDAY WITH MILDEST READINGS BY LAWRENCEVILLE. HAVE DRY AND COOL CONDITIONS MONDAY NIGHT THROUGH TUE NIGHT. THEN SMALL CHANCES OF SHOWERS WED/THU WITH A WEATHER SYSTEM APPROACHING FROM THE SW WITH GFS MODEL TRENDING MUCH WETTER DURING THIS TIME FRAME WHILE ECMWF MODEL IS KEEPING IL DRY. COOL HIGHS IN THE UPPER 50S/LOWER 60S TUE-WED WITH LOWS IN THE UPPER 30S TO MID 40S, WITH COOLEST READINGS FROM I-74 NORTH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1216 PM CDT FRI APR 17 2015 DIURNAL CU ACROSS THE REGION DEVELOPING AND VERY FEW OVER CMI...BUT MORE BKN TO THE SOUTH FOR SPI AND DEC POTENTIALLY THROUGH THE AFTERNOON. STILL VERY LIGHT AND VARIABLE WINDS EXPECTED ACROSS THE REGION...WITH MAINLY WESTERLY FLOW ALOFT. STILL PLENTY OF LLVL MOISTURE IN THE BOUNDARY LAYER TO LEND TO A SLIGHT REDUCTION OF VISIBILITY OVERNIGHT AND IN THE EARLY MORNING HOURS. HAVE CONTINUED THE TREND TO MAINLY MVFR VIS...BUT WILL HAVE TO KEEP A CLOSE EYE ON THE XOVER TEMPS THIS AFTERNOON. NOT MUCH IN THE WAY OF MIXING IS ANTICIPATED AGAIN WITH THE LIGHT FLOW...BUT SINCE WESTERN TERMINALS WERE RELATIVELY LIGHT VIS DROPS THIS MORNING...EXPECT SOME OF THAT WILL TRANSLATE EASTWARD. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HJS SHORT TERM...07 LONG TERM...07 AVIATION...HJS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
349 PM CDT Fri Apr 17 2015 .SHORT TERM...(This Evening through Saturday) Issued at 346 PM CDT FRI APR 17 2015 Upper low continues to spin over the Rockies this afternoon with an upper level jet rounding the base of the upper low and moving over New Mexico. Earlier showers and thunderstorms were moving out of the northern counties at 20Z. Some clearing was occurring across the southern and western sections of the cwa this afternoon. Latest meso analysis shows surface based CAPE around 500 to 1000 J/kg with an uncapped atmosphere. Expect scattered convection to develop in southwest Kansas along the dry line. additional scattered storms may develop in south west and south central Kansas per the latest runs of the RAP and HRRR. Models suggest additional development this evening across western and central Kansas moving northeast into north central Kansas with the increase and veering of the low level jet overnight. Models are in agreement with a lobe of energy working it`s way northeast out of Oklahoma later tonight and Saturday morning. May see a repeat of this morning with an area of showers and embedded thunderstorms moving across the area. Expect a break for a few hours in the afternoon, then chances increase again with storms developing again in the afternoon in western and central Kansas as upward vertical motion increases with the advance of the upper trough into the High Plains. Dryline looks to set up across western Kansas with the GFS the furthest east in central Kansas. Shear and instability will be favorable for some of the storms to be strong to severe with large hail and winds the main hazards in the late afternoon hours mainly west of a Herington to Washington line. .LONG TERM...(Saturday Night through Friday) Issued at 346 PM CDT FRI APR 17 2015 Short range models are relatively consistent in moving surface low and main piece of upper trough through eastern KS late Saturday night and Sunday. Ahead of this system Saturday night, increasing thunderstorm chances are expected, with some potential for severe weather, with the best chance in our forecast area over the western 2/3. Shear parameters are not very impressive and amount of sunshine and associated surface heating Sat afternoon and evening is also a little suspect so this is not a high probability thing. As the low and front move through on Sunday, some isolated thunder may continue in the east in the morning, but showers associated with cold air aloft just behind the front will continue precip chances into the afternoon hours. After that, subsidence and cold advection behind that system brings in dry conditions and cooler temperatures for Sunday night through Tuesday, with lows dipping into the upper 30s many places and highs in the low to mid 60s. Precip chances return to parts of eastern KS on Wednesday when weak low-level warm advection and a weak wave in northwest flow aloft interact. Latest ECMWF and GEM would indicate that the cool air at the surface is more entrenched in place than the GFS, thus have gone cooler than guidance for highs on Wednesday. Beyond Wednesday, considerable differences exist between 12Z GFS and ECMWF in upper flow pattern and precip chances. GFS and GFSEnsemble places us in a more favorable pattern for a couple days of precip for Thursday and Friday, while the ECMWF is slower in bringing a shortwave trough out of the southwest U.S., and would give us the better chances on Friday. Have gone with a general compromise with 25 to 40 percent POPs for those days. && .AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon) Issued at 105 PM CDT FRI APR 17 2015 VFR conditions are expected through the period outside of convection. Expect isolated tsra this afternoon and evening then a better chance of more widespread shra and isolated tsra after 08Z through the end of the period. MVFR vsbys are expected along with brief reductions of cigs into the mvfr category. Winds remain east southeast through the period generally less than 10 kts. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...53 LONG TERM...GDP AVIATION...53
AREA FORECAST DISCUSSION
NWS JACKSON KY
200 PM EDT FRI APR 17 2015 .UPDATE... ISSUED AT 200 PM EDT FRI APR 17 2015 QUICK UPDATE TO ALIGN T AND TD GRIDS WITH MOST RECENT OBS. NO OTHER CHANGES WERE MADE TO THE FORECAST. SENT UPDATED GRIDS TO NDFD AND WEB SERVERS. UPDATE ISSUED AT 1058 AM EDT FRI APR 17 2015 WV IMAGERY INDICATES THAT THE WEAK TROUGH HAS PUSHED EAST OF THE AREA SO HAVE TRENDED POPS DOWN OVER THE NEXT 3 TO 6 HOURS...STILL KEPT A SLIGHT CHANCE IN OUR SOUTHEASTERN COUNTIES TO REMAIN WITHIN TOLERANCE WITH OUR NEIGHBORS DURING THAT TIME. OTHERWISE...IT/S JUST A CLOUD COVER AND TEMPERATURE FORECAST TODAY. SO HAVE UPDATED T AND TD GRIDS TO ALIGN WITH MOST RECENT OBS. NO OTHER CHANGES WERE MADE TO THE CURRENT FORECAST BUT WILL KEEP AN EYE ON CLOUD COVER AND TEMPS INTO THE AFTERNOON. SENT UPDATED GRIDS TO NDFD AND WEB SERVERS. UPDATE ISSUED AT 809 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME LOW LEVEL CLOUDS JUST TO THE WEST ASSOCIATED WITH A WEAK TROUGH MOVING THROUGH. THIS HAS ALSO SPAWNED A FEW SHOWERS ACROSS THE AREA. RECENT RADAR RETURNS HINT AT SOME OF THE ACTIVITY MAYBE DEVELOPING FURTHER SOUTH SO HAVE LEFT POPS IN THROUGH MIDDAY. AS WELL HAVE PUT FOG IN THE FORECAST LATE TONIGHT. WITH HIGH PRESSURE MOVING INTO THE AREA AND CLEARING SKIES LATER TODAY...AS WELL A MOIST SURFACE LAYER AND LIGHT WINDS WILL BE A FAVORABLE ENVIRONMENT FOR FOG DEVELOPMENT. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME MOIST SOUTHERLY FLOW MOVING INTO KENTUCKY FROM THE SOUTHWEST THIS MORNING. AT THIS TIME...WEAK SURFACE HIGH PRESSURE CENTERED OVER MI IS POISED TO SLOWLY CREEP SOUTHEAST. IN THIS AREA OVER THE LOWER GREAT LAKES...A BIT OF CLEARING MAY MAKE IT INTO EAST KENTUCKY THIS MORNING. THIS COMBINED WITH THE MOISTURE PRESENT OVER THE AREA MAY RESULT IN SOME DENSE FOG DEVELOPMENT TOWARDS DAWN. AT THIS POINT...IT LOOKS LIKE A TOUGH CALL WITH CLOUD COVER CONTINUING TO STREAM IN FROM THE SOUTHWEST. HAVE PUT PATCHY FOG IN THE FORECAST TO COVER THIS BUT WILL ALSO MONITOR FOG DEVELOPMENT TOWARDS DAWN. IN ADDITION TO THIS...A WEAK REMNANT TROUGH SLIDING EAST AHEAD OF HIGH PRESSURE MAY BE ENOUGH TO SPAWN A FEW SHOWERS. HI RES MODELS SUCH AS THE HRRR DO HINT AT THIS INTO THE DAY AS THIS TROUGH SLOWLY SLIDES THROUGH. WITH NO REAL SURFACE FEATURE THIS ACTIVITY IS TIED TO...WILL GO WITH SLIGHT CHANCE POPS THROUGH MIDDAY AND ONLY SHOWERS EXPECTED. HEADING INTO TONIGHT...MENTIONED HIGH PRESSURE WILL MOVE INTO THE AREA TONIGHT. SOME BREAKS IN THE CLOUD COVER IS EXPECTED...ESPECIALLY OVER THE NORTH WHERE SOME CLEAR SKIES LOOK TO DEVELOP. THIS MAY POSE AS A BETTER FOG SET UP AND MAY NEED TO MENTION THIS IN THE HWO. BY SATURDAY...A CLOSED UPPER LOW EJECTS INTO THE CENTRAL PLAINS...AND A SHORTWAVE MOVES OUT OF THE BASE OF THE LOW...CROSSING THE LOWER MS RIVER VALLEY AND NORTHEAST INTO THE OH AND TN VALLEYS. SURFACE LOW PRESSURE AND A DEVELOPING WARM FRONT WILL BRING A SURGE OF MOIST AIR INTO EAST KENTUCKY WITH A SLIGHT CHANCE POPS MAKING MAKING IT INTO POINTS SOUTH OF THE HAL ROGERS PARKWAY BY SATURDAY AFTERNOON. MODELS WITH THIS FEATURE HAVE BEEN PRETTY CONSISTENT AND THE BEST CHANCE OF MEASURABLE PRECIP WILL BE AFTER 00Z SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 335 AM EDT FRI APR 17 2015 CLOSED UPPER LEVEL LOW THAT HAS BEEN QUASI STATIONARY ACROSS THE DESERT SW WILL FINALLY BEGIN PHASING WITH A NORTHERN STREAM TROUGH AS WE MOVE INTO THE LONG RANGE PERIOD. DIFFLUENCE ALOFT...JET ENERGY... AND SHORTWAVE WILL AID IN DEVELOPING SURFACE LOW PRESSURE ACROSS THE SOUTHERN MISSISSIPPI RIVER VALLEY SATURDAY NIGHT. THIS WILL HELP TO SPREAD SHOWERS AND THUNDERSTORMS ACROSS THE REGION AS WE MOVE THROUGH THE DAY ON SUNDAY. MODEL SOUNDINGS WOULD SUGGEST PWATS BETWEEN 1.2 AND 1.4 INCHES DURING THIS PERIOD AS COLUMN SATURATES...THEREFORE SOME OF THESE SHOWERS AND STORMS WILL LIKELY BE MODERATE INTENSITY AT TIMES. GIVEN THE VERY WET ANTECEDENT CONDITIONS WE COULD SEE ISOLATED FLOODING THREAT ONCE AGAIN. THIS WILL DEPEND ON THE DEVELOPMENT AND MOVEMENT OF THE LOW PRESSURE THAT DEVELOPS AND MOVES NORTH NORTHEAST SUNDAY AND ALSO ANY CONVECTION THAT DEVELOPS. THIS UPPER LEVEL SYSTEM DOES LOOK TO PHASE WITH THE NORTHERN STREAM TROUGH AS MENTIONED ABOVE AND A CLOSED UPPER LEVEL LOW DEVELOPS ACROSS THE NORTHERN PLAINS. THIS WILL MAKE FOR A TWO PART SYSTEM AS ANOTHER SURFACE LOW DEVELOPS ACROSS THE UPPER MIDWEST SUNDAY EVENING ASSOCIATED WITH A SPOKE OF ENERGY FROM THE CLOSED UPPER LEVEL LOW. THIS LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION MONDAY AND RESULT IN ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. UP TO THIS POINT WE DO SEE GOOD MODEL AGREEMENT IN REGARDS TO THIS SYSTEM. PASSAGE OF THIS FRONT WILL BREAKDOWN THE PATTERN WITH MORE OF A WESTERLY FLOW AND COOLER AIR USHERED IN BEHIND THE FRONT. AN AREA OF HIGH PRESSURE WILL BUILD TO THE SOUTH WITH HIGHS TEMPS IN THE LOW TO MID 60S AND LOWS IN THE UPPER TO EVEN LOWER 40S TUESDAY INTO WEDNESDAY. MORE DIVERGENCE IN THE MODEL GUIDANCE EXISTS IN THE WEDNESDAY TO THURSDAY TIME FRAME. RIGHT NOW THE GFS AND GFS ENSEMBLE MEAN ARE WETTER THAN THE ECMWF AT THIS POINT. GIVEN THE UNCERTAINTY THAT EXISTS WILL LEAN TOWARD THE MODEL BLEND. THIS WILL BRING SLIGHT POPS ACROSS THE NORTH WEDNESDAY AFTERNOON AND CHANCE TO SLIGHT POPS WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 155 PM EDT FRI APR 17 2015 LOW LEVEL CLOUDS HAVE HAD A HARD TIME BREAKING UP THIS AFTERNOON. BUT GIVEN RECENT VIS IMAGERY TRENDS...EXPECT MUCH OF THE REMAINING CLOUD COVER TO CONTINUE BREAKING UP AND CIGS TO IMPROVE TO VFR THROUGHOUT THE REMAINDER OF THE AFTERNOON. HIGH PRESSURE MOVING IN LATER THIS EVENING AND TONIGHT ALONG WITH LIGHT WINDS WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR FOG DEVELOPMENT AND SO HAVE PUT IFR VIS IN THE LOZ...JKL...SJS...SYM TAF SITES AND ALTERNATE MINS AT THE SME TAF SITE TONIGHT AFTER 06Z. CONDITIONS SHOULD THEN IMPROVE TO VFR ACROSS ALL TAF SITES AROUND 13Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JVM SHORT TERM...SHALLENBERGER LONG TERM...DJ AVIATION...JVM
AREA FORECAST DISCUSSION
NWS JACKSON KY
155 PM EDT FRI APR 17 2015 .UPDATE... ISSUED AT 1058 AM EDT FRI APR 17 2015 WV IMAGERY INDICATES THAT THE WEAK TROUGH HAS PUSHED EAST OF THE AREA SO HAVE TRENDED POPS DOWN OVER THE NEXT 3 TO 6 HOURS...STILL KEPT A SLIGHT CHANCE IN OUR SOUTHEASTERN COUNTIES TO REMAIN WITHIN TOLERANCE WITH OUR NEIGHBORS DURING THAT TIME. OTHERWISE...IT/S JUST A CLOUD COVER AND TEMPERATURE FORECAST TODAY. SO HAVE UPDATED T AND TD GRIDS TO ALIGN WITH MOST RECENT OBS. NO OTHER CHANGES WERE MADE TO THE CURRENT FORECAST BUT WILL KEEP AN EYE ON CLOUD COVER AND TEMPS INTO THE AFTERNOON. SENT UPDATED GRIDS TO NDFD AND WEB SERVERS. UPDATE ISSUED AT 809 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME LOW LEVEL CLOUDS JUST TO THE WEST ASSOCIATED WITH A WEAK TROUGH MOVING THROUGH. THIS HAS ALSO SPAWNED A FEW SHOWERS ACROSS THE AREA. RECENT RADAR RETURNS HINT AT SOME OF THE ACTIVITY MAYBE DEVELOPING FURTHER SOUTH SO HAVE LEFT POPS IN THROUGH MIDDAY. AS WELL HAVE PUT FOG IN THE FORECAST LATE TONIGHT. WITH HIGH PRESSURE MOVING INTO THE AREA AND CLEARING SKIES LATER TODAY...AS WELL A MOIST SURFACE LAYER AND LIGHT WINDS WILL BE A FAVORABLE ENVIRONMENT FOR FOG DEVELOPMENT. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM EDT FRI APR 17 2015 CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME MOIST SOUTHERLY FLOW MOVING INTO KENTUCKY FROM THE SOUTHWEST THIS MORNING. AT THIS TIME...WEAK SURFACE HIGH PRESSURE CENTERED OVER MI IS POISED TO SLOWLY CREEP SOUTHEAST. IN THIS AREA OVER THE LOWER GREAT LAKES...A BIT OF CLEARING MAY MAKE IT INTO EAST KENTUCKY THIS MORNING. THIS COMBINED WITH THE MOISTURE PRESENT OVER THE AREA MAY RESULT IN SOME DENSE FOG DEVELOPMENT TOWARDS DAWN. AT THIS POINT...IT LOOKS LIKE A TOUGH CALL WITH CLOUD COVER CONTINUING TO STREAM IN FROM THE SOUTHWEST. HAVE PUT PATCHY FOG IN THE FORECAST TO COVER THIS BUT WILL ALSO MONITOR FOG DEVELOPMENT TOWARDS DAWN. IN ADDITION TO THIS...A WEAK REMNANT TROUGH SLIDING EAST AHEAD OF HIGH PRESSURE MAY BE ENOUGH TO SPAWN A FEW SHOWERS. HI RES MODELS SUCH AS THE HRRR DO HINT AT THIS INTO THE DAY AS THIS TROUGH SLOWLY SLIDES THROUGH. WITH NO REAL SURFACE FEATURE THIS ACTIVITY IS TIED TO...WILL GO WITH SLIGHT CHANCE POPS THROUGH MIDDAY AND ONLY SHOWERS EXPECTED. HEADING INTO TONIGHT...MENTIONED HIGH PRESSURE WILL MOVE INTO THE AREA TONIGHT. SOME BREAKS IN THE CLOUD COVER IS EXPECTED...ESPECIALLY OVER THE NORTH WHERE SOME CLEAR SKIES LOOK TO DEVELOP. THIS MAY POSE AS A BETTER FOG SET UP AND MAY NEED TO MENTION THIS IN THE HWO. BY SATURDAY...A CLOSED UPPER LOW EJECTS INTO THE CENTRAL PLAINS...AND A SHORTWAVE MOVES OUT OF THE BASE OF THE LOW...CROSSING THE LOWER MS RIVER VALLEY AND NORTHEAST INTO THE OH AND TN VALLEYS. SURFACE LOW PRESSURE AND A DEVELOPING WARM FRONT WILL BRING A SURGE OF MOIST AIR INTO EAST KENTUCKY WITH A SLIGHT CHANCE POPS MAKING MAKING IT INTO POINTS SOUTH OF THE HAL ROGERS PARKWAY BY SATURDAY AFTERNOON. MODELS WITH THIS FEATURE HAVE BEEN PRETTY CONSISTENT AND THE BEST CHANCE OF MEASURABLE PRECIP WILL BE AFTER 00Z SUNDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 335 AM EDT FRI APR 17 2015 CLOSED UPPER LEVEL LOW THAT HAS BEEN QUASI STATIONARY ACROSS THE DESERT SW WILL FINALLY BEGIN PHASING WITH A NORTHERN STREAM TROUGH AS WE MOVE INTO THE LONG RANGE PERIOD. DIFFLUENCE ALOFT...JET ENERGY... AND SHORTWAVE WILL AID IN DEVELOPING SURFACE LOW PRESSURE ACROSS THE SOUTHERN MISSISSIPPI RIVER VALLEY SATURDAY NIGHT. THIS WILL HELP TO SPREAD SHOWERS AND THUNDERSTORMS ACROSS THE REGION AS WE MOVE THROUGH THE DAY ON SUNDAY. MODEL SOUNDINGS WOULD SUGGEST PWATS BETWEEN 1.2 AND 1.4 INCHES DURING THIS PERIOD AS COLUMN SATURATES...THEREFORE SOME OF THESE SHOWERS AND STORMS WILL LIKELY BE MODERATE INTENSITY AT TIMES. GIVEN THE VERY WET ANTECEDENT CONDITIONS WE COULD SEE ISOLATED FLOODING THREAT ONCE AGAIN. THIS WILL DEPEND ON THE DEVELOPMENT AND MOVEMENT OF THE LOW PRESSURE THAT DEVELOPS AND MOVES NORTH NORTHEAST SUNDAY AND ALSO ANY CONVECTION THAT DEVELOPS. THIS UPPER LEVEL SYSTEM DOES LOOK TO PHASE WITH THE NORTHERN STREAM TROUGH AS MENTIONED ABOVE AND A CLOSED UPPER LEVEL LOW DEVELOPS ACROSS THE NORTHERN PLAINS. THIS WILL MAKE FOR A TWO PART SYSTEM AS ANOTHER SURFACE LOW DEVELOPS ACROSS THE UPPER MIDWEST SUNDAY EVENING ASSOCIATED WITH A SPOKE OF ENERGY FROM THE CLOSED UPPER LEVEL LOW. THIS LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION MONDAY AND RESULT IN ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. UP TO THIS POINT WE DO SEE GOOD MODEL AGREEMENT IN REGARDS TO THIS SYSTEM. PASSAGE OF THIS FRONT WILL BREAKDOWN THE PATTERN WITH MORE OF A WESTERLY FLOW AND COOLER AIR USHERED IN BEHIND THE FRONT. AN AREA OF HIGH PRESSURE WILL BUILD TO THE SOUTH WITH HIGHS TEMPS IN THE LOW TO MID 60S AND LOWS IN THE UPPER TO EVEN LOWER 40S TUESDAY INTO WEDNESDAY. MORE DIVERGENCE IN THE MODEL GUIDANCE EXISTS IN THE WEDNESDAY TO THURSDAY TIME FRAME. RIGHT NOW THE GFS AND GFS ENSEMBLE MEAN ARE WETTER THAN THE ECMWF AT THIS POINT. GIVEN THE UNCERTAINTY THAT EXISTS WILL LEAN TOWARD THE MODEL BLEND. THIS WILL BRING SLIGHT POPS ACROSS THE NORTH WEDNESDAY AFTERNOON AND CHANCE TO SLIGHT POPS WEDNESDAY NIGHT INTO THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 155 PM EDT FRI APR 17 2015 LOW LEVEL CLOUDS HAVE HAD A HARD TIME BREAKING UP THIS AFTERNOON. BUT GIVEN RECENT VIS IMAGERY TRENDS...EXPECT MUCH OF THE REMAINING CLOUD COVER TO CONTINUE BREAKING UP AND CIGS TO IMPROVE TO VFR THROUGHOUT THE REMAINDER OF THE AFTERNOON. HIGH PRESSURE MOVING IN LATER THIS EVENING AND TONIGHT ALONG WITH LIGHT WINDS WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR FOG DEVELOPMENT AND SO HAVE PUT IFR VIS IN THE LOZ...JKL...SJS...SYM TAF SITES AND ALTERNATE MINS AT THE SME TAF SITE TONIGHT AFTER 06Z. CONDITIONS SHOULD THEN IMPROVE TO VFR ACROSS ALL TAF SITES AROUND 13Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JVM SHORT TERM...SHALLENBERGER LONG TERM...DJ AVIATION...JVM
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
151 PM CDT FRI APR 17 2015 .DISCUSSION... 17/18Z TAF ISSUANCE. && .AVIATION... MUCH IMPROVED CONDITIONS TODAY COMPARED TO YESTERDAY. MAINLY SCT/BKN CUMULUS OVER THE REGION...WITH PREVAILING VFR AND OCNL MVFR CIGS AT TAF SITES EARLY THIS AFTN. THESE CONDITIONS WILL CONTINUE INTO THE EVENING...WITH CONDITIONS AGAIN DETERIORATING OVERNIGHT FROM WEST TO EAST AS THE NEXT DISTURBANCE APPROACHES. CIGS WILL LOWER TO LOW END MVFR OR IFR AFTER 06Z...WITH SHRA/TSRA DEVELOPING. CONVECTION WILL BECOME MORE WIDESPREAD THROUGH SATURDAY MORNING...WITH GUSTY WINDS AND HEAVY RAIN EXPECTED WITHIN SOME OF THE STRONGER STORMS. 24 && .PREV DISCUSSION... /ISSUED 1050 AM CDT FRI APR 17 2015/ DISCUSSION... AFTER A FUN DAY YESTERDAY...LOCAL 88DS ARE REFRESHINGLY QUIET THIS MORNING WITH MAINLY JUST RAINS ASSOCIATED WITH A DEPARTING DISTURBANCE ALOFT EXITING THE ERN COASTAL WATERS AND POSSIBLY BRUSHING LOWER ACADIANA. 12Z KLCH SOUNDING SHOWED A MUCH DRIER AIRMASS IN PLACE OVER THE REGION TODAY...WHILE THE MODIFIED SOUNDING SHOWED SIMILAR INSTABILITY TO THURSDAY. PLAYING TO OUR ADVANTAGE TODAY IS A RELATIVE LACK OF APPROACHING DISTURBANCES ROUNDING THE UPPER LOW OVER THE FOUR CORNERS REGION. HOWEVER GIVEN THAT WE ARE STILL REASONABLY MOIST AND FAIRLY UNSTABLE...DAYTIME HEATING OR PERHAPS SOME LINGERING BOUNDARIES FROM EARLIER CONVECTION COULD STILL SPARK SOME SHOWERS AND STORMS ESPECIALLY THIS AFTERNOON. DESPITE WHAT LOOKS LIKE A LACK OF PRECIP TODAY...STILL EXPECTING ANOTHER HEAVY RAINFALL EVENT BEGINNING TONIGHT AND RUNNING INTO SATURDAY. GIVEN THE FLOODING WHICH OCCURRED YESTERDAY AND THE SATURATED GROUNDS LEFT BEHIND FROM ALL THE RAIN...EXTENDED THE INHERITED FLASH FLOOD WATCH THROUGH LATE TOMORROW AFTERNOON. ELSEWHERE JUST TWEAKED GRIDS/ZONES BASED ON LATEST OBS/TRENDS... UPDATE ALREADY OUT. 25 PREV DISCUSSION... /ISSUED 616 AM CDT FRI APR 17 2015/ AVIATION...SINCE MIDNIGHT CONVECTIVE ACTIVITY HAS DECREASED SIGNIFICANTLY. RADAR NOW SHOWING JUST A FEW SHOWERS AND THUNDERSTORMS AND THESE OFFSHORE OVER THE NEAR COASTAL WATERS. TODAY LOOKS TO WITH MUCH LESS CONVECTION OVER THE AREA AS SOME SHARPLY DRIER MID LEVEL AIR ADVECTS INTO THE REGION. MODELS SUGGESTING A RAMPING UP OF PRECIP OVERNIGHT AS ANOTHER UPPER LEVEL DISTURBANCE APPROACHES. ALTOCU CLOUDS AT AROUND 10KT FT CURRENTLY OVER AREA. WILL SEE LOWER CLOUDS DEVELOP AS THE MORNING PROGRESSES BUT WILL MAINTAIN THESE WITHIN VFR. 25 PREV DISCUSSION... /ISSUED 335 AM CDT FRI APR 17 2015/ DISCUSSION...POPS AND HEAVY RAIN WILL BE THE MAIN FORECAST ISSUES OVER THE NEXT 48 HOURS. WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY YESTERDAY AND OVERNIGHT WAS BEGINNING TO DECREASE AS OF 08Z. THE LATEST HRRR CONFIRMS THIS WITH ACTIVITY DECREASING SIGNIFICANT LATER THIS MORNING ESPECIALLY OVER EASTERN PARTS OF THE FORECAST AREA. WILL CONTINUE WITH FFA FOR NOW...BUT MAY CANCEL EARLY IF WEAKENING TREND CONTINUES. WILL TAPER POPS TO MID RANGE FOR THIS AFTERNOON. MODELS HAVE BEEN CONSISTENT IN LIFTING UPPER TROUGH NE THROUGH THE WEEKEND. ALSO...APPEARS THAT NEXT ROUND OF SHOWERS AND THUNDERSTORMS WILL BEGIN LATE TONIGHT AND BECOME MORE WIDESPREAD ON SATURDAY. WILL LIKELY NEED TO REISSUE FFA FOR TONIGHT AND SATURDAY. AFTER SATURDAY...A MUCH NEEDED PATTERN CHANGE IS FORECASTED. WEAK UPPER RIDGE SHOULD DEVELOP OVER THE GULF COAST STATES. A FRONTAL BOUNDARY SHOULD MOVE THROUGH THE AREA BY SUNDAY NIGHT AND THIS WILL LIKELY BRING DRY WEATHER FOR EARLY NEXT WEEK. FRONT IS FORECASTED TO STALL OVER THE GULF AND RETURN NORTH LATE IN THE WEEK. AT THIS TIME...WILL KEEP LOW POPS IN THE FORECAST ALTHOUGH LATEST MODELS ARE SHOWING A DEEPER MOISTURE PROFILE THIS CYCLE. MARINE...PERIODIC SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGH THE EARLY PART OF THE WEEKEND. OTHERWISE HIGH PRESSURE OVER THE EASTERN GULF AND LOW PRESSURE OVER WEST TEXAS WILL MAINTAIN ONSHORE FLOW THROUGH SUNDAY. MODELS CONTINUE TO BRING FRONT INTO THE NORTHERN GULF SUNDAY NIGHT ALLOWING FOR A BRIEF PERIOD OF OFFSHORE FLOW. WEAK TO MODERATE EASTERLY FLOW IS ANTICIPATED FOR EARLY NEXT WEEK AS HIGH PRESSURE SETTLES OVER THE SE U.S. AP && .PRELIMINARY POINT TEMPS/POPS... AEX 81 66 77 62 / 30 70 80 40 LCH 82 67 77 64 / 40 70 80 40 LFT 81 69 78 65 / 40 60 90 40 BPT 82 67 79 64 / 40 70 70 40 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR LAZ027>033- 041>045-052>055-073-074. TX...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR TXZ180-201-215- 216-259>262. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1222 PM CDT Fri Apr 17 2015 .DISCUSSION... Issued at 435 AM CDT FRI APR 17 2015 Today - Tonight: Today will be a transition day. An upper ridge, now overhead, has kept the KS/OK/TX Panhandle convection at bay since yesterday. However, as the upper ridge nudges east this convection will be able to edge closer and closer. This activity has been generated by weak impulses ejecting from a cut-off upper low near the 4-corners area and mid-level frontogenesis. This upper low has moved little over the past 24 hours as it awaits its kicker which is just now crossing into British Columbia. This latter feature is expected to strengthen later today as upstream ridging sharpens and forces this shortwave trough to dig southeast into the Northern Rockies...but not until tomorrow. What this means is any convection reaching the CWA today will weaken/fall apart as it moves away from the better upper support. Having said that there are some signals from the last couple runs of the HRRR and to a lesser extent the 00z NAM that convection now moving east through northern OK/south central KS could reach the far western counties by around the noon hour. Regional radars show an outflow boundary now expanding east from the KS convection with new activity sprouting over north central OK. This activity is what the HRRR picks up on and lifts northeast later this morning. So, will slowly shift chance PoPs across the far western CWA today while leaving the eastern half dry. Convective debris clouds will also thin as they spread east today providing a thin veil of high clouds. This shouldn`t hold back warming and expect temperatures to top out in the middle and upper 70s. The Southern Plateau closed low will gradually shift east tonight, allowing new convection to push further east and become more organized as it reaches the KS/MO state line towards sunrise. Will handle this with a steady and gradual increase in PoPs through the night. Saturday - Sunday: A very wet period with convection becoming numerous and likely coming in waves as cells track nne while shifting slowly east. Model precipitable water values 2 to 3 standard deviations are a cause for concern. Steering winds in the 20kt area plus this moisture heighten the threat of localized flooding. Have increased qpf and this may even be underdone as its certainly feasible that some areas could see up to 2 inches of rain through Saturday night. Extensive cloud cover and rain-cooled air forces me to lower highs on both days and won`t be surprised if they are lowered further in future forecasts. Modest MLCAPEs and 0-6km shear in the 20-30kt range are not likely to support any severe threat on Saturday. Sunday may be a slightly different story. By then the closed upper low will have opened up and accelerated eastward. There is a chance we could be rain free Sunday morning with some partial sunshine. Should this occur more robust afternoon convection could form within a marginally supportive airmass featuring MLCAPEs of 1200-1400 J/kg but only 25-30kt 0-6 km bulk shear. Monday - Friday: The shortwave trough which will act as the kicker to move the current closed upper low near the 4-corners will have formed into a well developed upper trough from the Upper MS Valley through the Mid MO Valley early in this period. As the upper trough axis passes through on Monday strong subsidence and cold air advection will provide ample sunshine but below average temperatures through Tuesday. By mid week, an upper ridge axis will build east into the Central Plains with warm air advection spreading east. The GFS is more aggressive and faster than the ECMWF in pushing weak mid level vorticity lobes through the ridge axis. These features will be ejected from a broad upper trough that will works into the desert southwest. Difficult to determine how soon any scattered convection could work its way back into the region. For now will introduce some low chance PoPs for late Wednesday into Thursday. The current closed upper low now over northern Mexico is expected to weaken as it lifts north-northeast through the Central Plains and CWA. While there should be decent moisture lifted northward with this feature minimal instability will limit amount of thunder. Given that the operational models have been generating a similar solution believe 30-40 PoPs are warranted for scattered convection. Thursday - Sunday: Roll of the dice as to how weather will evolve from Thursday through Sunday. Not especially fond of the blended model approach of carpet bombing chance PoPs in every period. The medium range models drop a deep upper trough into the Desert Southwest and then cut it off. Models typically are challenged significantly with these features initially. They tend to lift them out too soon and too far east. Will be interesting to see how this system is handled going forward. Difficult trying to time any weak impulse ejected from this system within the downstream southwesterly flow. For now will handle this with low chance PoPs with above average temperatures. && .AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon) Issued at 1217 PM CDT FRI APR 17 2015 Band of showers will continue moving northeast, gradually weakening while isolated convection will develop ahead of the activity. Lightning has been on the decrease as the band has weakened, and with the anticipated more scattered nature with time, expect VCSH instead of prevailing period of precipitation. Rain should clear terminal by mid-afternoon, with a lull in activity through midnight. Next round of showers and embedded thunderstorms expected overnight, with one or more rounds of convection through the end of the TAF period. Will likely see periods of reduced visibility with overnight activity, but prediction of specific reduction time is low and precludes mention at this time. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ DISCUSSION...MJ AVIATION...Blair
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1203 PM CDT FRI APR 17 2015 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 318 AM CDT FRI APR 17 2015 PCPN CHANCES AND TEMPERATURES ARE THE PRIMARY FORECAST CONCERNS IN THE TODAY PERIOD...THEN CONTINUED SHOWER/THUNDERSTORM CHANCES ESPECIALLY FRIDAY NIGHT THROUGH SATURDAY NIGHT...THEN THE COLD FRONTAL PASSAGE AND PRECIPITATION ENDING SUNDAY. REGIONAL RADAR EARLY THIS MORNING SHOWS AREA OF SHOWERS AND ISOLATED THUNDERSTORMS PIVOTING NORTH TO NORTHWEST FROM KANSAS INTO NEBRASKA AROUND CLOSED UPPER LOW OVER SOUTH CENTRAL COLORADO. WESTERN PORTIONS OF THE FORECAST AREA WILL BE MOST LIKELY TO SEE PRECIP TODAY WITH EASTERN AREAS HAVING TO WAIT UNTIL THE AFTERNOON FOR BETTER POPS AS THE UPPER LOW TRACKS SLOWLY EAST. RAP FORECAST SOUNDINGS SHOW LIMITED INSTABILITY THROUGH MOST OF THE DAY ESPECIALLY IN THE EAST AND NORTH WITH INCREASING INSTABILITY IN WESTERN PARTS OF THE AREA ALONG AND WEST OF A BEATRICE-LINCOLN- COLUMBUS ARC BY LATE AFTERNOON. CLOUD COVER IS EXPECTED TO REMAIN IN PLACE MUCH OF THE DAY FOR THE WEST HALF OF THE AREA WITH VARIABLE SKY COVER IN THE EAST HALF. THIS SPLIT SHOULD SEE LOWER TEMPS AROUND 70 CONFINED TO THE WEST WITH MID 70S IN THE EAST WHERE SOME PERIODS OF SUN ARE POSSIBLE. TONIGHT...THE OPERATIONAL MODELS ARE IN GOOD AGREEMENT THAT THE CLOSED H5 LOW OVER THE FOUR-CORNERS REGION WILL LIFT NORTHEAST TO COLORADO BY 00Z TONIGHT. THE H5 LOW MEANDERS OVER COLORADO THROUGH SATURDAY...THEN DRIFTS INTO WESTERN KANSAS BY 06Z. THE NAM IS SLIGHTLY DIFFERENT IN SPLITTING SOME OF THE H5 ENERGY TO THE NORTH IN SOUTH DAKOTA AND THE CLOSED LOW A LITTLE FARTHER SOUTH TOWARD OKLAHOMA. SHOWERS AND THUNDERSTORMS SHOULD BE ONGOING OVER PARTS OF THE CWA AND WILL CONTINUE TO SPREAD NORTH AND EAST FRIDAY NIGHT AND SATURDAY. THESE PERIODS WILL HAVE THE HIGHEST POPS THIS WEEKEND. THE INSTABILITY AXIS DOES LIFT NORTHWARD FRIDAY NIGHT AND CONTINUES OVER THE AREA SATURDAY. THERE IS ALSO AN H85 BOUNDARY IN THIS REGION THAT LIFTS NORTH AND MAY PROVIDE A FOCUS FOR ENHANCED CONVECTIVE ACTIVITY. SOME .25-.5 INCH RAINS FELL ALONG WITH PEA TO DIME- SIZED HAIL WAS REPORTED WITH SOME OF THE STORMS IN SOUTHERN NEBRASKA THURSDAY NIGHT. FORECAST SOUNDINGS SHOW WEAK INSTABILITY WITH MLCAPE OF 200J/KG FRIDAY NIGHT...AND A LITTLE BETTER INSTABILITY WITH MLCAPE OF 500J/KG SATURDAY. SOME OF THE STRONGER STORMS MAY PRODUCE SOME HAIL. RAINFALL AMOUNTS THROUGH SATURDAY COULD RANGE FROM .5 TO 1 INCH. SATURDAY NIGHT...THE MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TO SHIFT FARTHER EAST INTO IOWA AND EXTEND IN A LARGE AREA FROM THE GULF STATES THROUGH THE MISSISSIPPI VALLEY INTO MINNESOTA AND THE DAKOTA. THE LOW LEVEL JET OF 40-50KTS DEVELOPS OVER IOWA INTO MINNESOTA AND EVENTUALLY WI. THE H85 THERMAL RIDGE IS OVER THE FORECAST AREA. BY 12Z SUNDAY THE GFS/NAM/EC ARE SIMILAR AND HAVE THE SURFACE LOW OVER NORTHEAST NEBRASKA WITH A FRONT OVER FAR EASTERN NEBRASKA INTO WESTERN IOWA. THIS BOUNDARY IS EAST OF THE AREA BY 18Z. WITH THE LONGWAVE TROF STILL MOVING THROUGH THE AREA...THERE WILL STILL BE SCATTERED SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND SUNDAY MORESO IN SOUTHEAST NEBRASKA. NORTHWEST WINDS BEHIND THE FRONT TURN WINDY 15 TO 25KTS AT THE SURFACE WITH 40 TO 50KTS AT H85. THE MOISTURE DRIES OUT TO .5-.75 PWAT BY 00Z AND 0.25 OF AN INCH PWAT BY 12Z MONDAY. .LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 318 AM CDT FRI APR 17 2015 THE CLOSED MID TROPOSPHERIC LOW OVER THE UPPER MISSISSIPPI VALLEY MONDAY...SHIFTS TO THE UPPER GREAT LAKES TUESDAY...AND LINGERS THERE THROUGH THURSDAY. IT SHOULD BE DRY SUNDAY NIGHT THROUGH TUESDAY. HIGHS SHOULD BE IN THE 50S AND 60S. THE GFS IS SLIGHTLY FARTHER NORTH WITH LOW...AND THIS ALLOWS A STORM SYSTEM THAT MOVES INTO THE WESTERN U.S. TO AFFECT THE LOCAL AREA WITH SHOWERS AND ISOLATED THUNDERSTORMS WEDNESDAY INTO THE REST OF THE WEEK. THE EC IS MAINLY DRY THRU THURSDAY. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1158 AM CDT FRI APR 17 2015 VFR CONDITIONS ARE EXPECTED THROUGH TODAY...WITH CEILINGS AROUND 5-8KFT. LATE AFTERNOON TO EVENING...INCREASING COVERAGE OF SHOWERS WILL BRING AT LEAST A VICINITY THREAT TO KOFK AND KLNK...WITH MORE WIDESPREAD POTENTIAL AFTER 02Z. ANY SHOWERS AFFECTING TAF SITES MAY BRING THUNDER...AS WELL AS VIS AND POSSIBLY EVEN CIGS INTO MVFR RANGE. HAVE JUST MENTIONED THE SHOWERS AND VIS RESTRICTIONS FOR NOW...WITH TIME YET TO MODIFY AS TIMING OF SHOWERS BECOMES MORE EVIDENT. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT/ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...MAYES
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
144 PM EDT FRI APR 17 2015 .SYNOPSIS... A WEAK COLD FRONT WILL MOVE ACROSS CENTRAL NEW YORK EARLY THIS AFTERNOON AND NORTHEAST PENNSYLVANIA BY LATE AFTERNOON. THIS FRONT WILL TRIGGER A FEW SHOWERS WITH AN ISOLATED THUNDERSTORM IN NORTHEAST PENNSYLVANIA. ANOTHER COLD FRONT WILL PASS ACROSS THE REGION SATURDAY. THIS FRONT COULD TRIGGER SOME SHOWERS IN NORTHERN AND EASTERN NEW YORK WITH MAINLY DRY WEATHER IN CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA. HIGH PRESSURE AND COOLER WEATHER WILL BUILD ACROSS THE REGION FOR SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WATER VAPOR IMAGERY SHOWS A SHORT WAVE MOVING ACROSS THE EASTERN GREAT LAKES AND EASTERN OHIO VALLEY THIS MORNING. THIS WAVE WILL PUSH A WEAK FRONT ACROSS THE REGION THIS AFTERNOON WITH SOME LL DRY ADVECTION BEHIND THE FRNT. THE FRONT AND LIFT ASSCTD WITH THE SHRT WAVE WILL TRIGGER ISLD TO SCT SHRA ACRS C NY/NE PA THIS AFTERNOON. THE FRNT COMES THRU AT MAX HEATING LATE THIS AFTERNOON ESP IN NE PA. CAPES ON THE HI RES MODELS NOW ARE RANGING FROM ARND 250 TO 500 J/KG IN NE PA ARND 21Z WITH THE HIGHER RESOLUTION MODELS SHOWING SCT CONVECTIVE CELLS FORMING ON SIMULATED RADAR FIELDS. THE BULK SHEAR IS ARND 20 KNOTS 0-1 KM AND 0-3 KM AND ABT 35 KNOTS 0-6 KM. FORCING IS NOT STRG BUT I HAVE ADDED ISLD TSRA TO NE PA GRIDS. I MAY HAVE TO ADJUST THIS UP EVEN MORE AS RECENT RAP AND HRRR RUNS HAVE MORE CAPE. WILL CONT TO MONITOR. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... NW FLOW ALOFT TNGT WITH WEAK SFC FEATURES WILL RESULT IN A QUIET PD WITH LGT WINDS AND BKN CLDS. WHILE A SHWR CAN/T BE RULED OUT...NOT ENUF OF A CHANCE TO INCLUDE IN THE FCST ATTM. SATURDAY WILL SEE A SHRT WV PASSING THRU NRN NEW ENG AND SOME LATE DAY CAA IN THE WAKE OF THE WV. MODELS SHOW VERY DRY AIR OVER THE AREA WITH THE BEST FRCG STAYING TO THE NE. SOME INSTABILITY LIKELY WITH THE LWRD HGTS BUT DRY AIR SHD INHIBIT ANY SHWRS FROM FRMG IN THE FCST AREA...ALTHOUGH NRN ONEIDA WILL BE CLOSE. UPR RDGG OVER THE GREAT LAKES WILL ALLOW SFC HIPRES TO SLIDE INTO THE AREA ON SUNDAY. TEMPS WILL BE A BIT LWR WITH THE CAA BUT DRIER AIR SHD ALLOW FOR MSTLY SUNNY SKIES. && .LONG TERM /MONDAY THROUGH FRIDAY/... 0245 AM UPDATE...ONLY MADE A FEW ADJUSTMENTS TO PREVIOUS FORECAST MADE DURING THE DAY SHIFT THURSDAY. MAIN CHANGE WAS TO ADJUST HIGH TEMPS DOWN FOR MONDAY, WEDNESDAY, AND THURSDAY OF NEXT WEEK AS GUIDANCE CONTINUES TO INDICATE WE WILL BE COOLER AND MORE UNSETTLED UNDER THE INFLUENCE OF AN UPPER LEVEL TROUGH. 445 PM THURSDAY UPDATE... MODELS IN GOOD AGREEMENT ON MOIST OCCLUDED FRONT LIKELY TO BRING RAIN AS IT SWEEPS THROUGH THE REGION LATE SUNDAY NIGHT THROUGH MONDAY. SHOWALTER INDICES ONLY GET TO AROUND ZERO...SHOWING ONLY SMALLEST HINT OF ELEVATED INSTABILITY...SO CHANCE OF EMBEDDED THUNDER DURING THAT PERIOD LOOKS MINIMAL TO NONE. QUARTER TO HALF INCH OF RAIN LOOKS QUITE DOABLE HOWEVER. CUTOFF LOW CURRENTLY OVER FOUR CORNERS REGION...IS DEPICTED BY GFS-ECMWF TO MERGE WITH A DIGGING NORTHERN STREAM TROUGH OVER THE MIDWEST THIS WEEKEND. THOSE FEATURES WILL COMBINE INTO A NEW LARGER CUTOFF LOW...THE CENTER OF WHICH WILL SLOWLY SLOG ITS WAY OVER THE WESTERN GREAT LAKES NEXT WEEK. THIS UPPER LOW WILL HAVE A LARGE FOOTPRINT WITH DISTURBANCES-WAVES ROTATING AROUND IT ACROSS GREAT LAKES TO NORTHEAST. MODELS DISAGREE ON LOCATION OF UPPER LOW CENTER BY THURSDAY /EITHER CENTRAL GREAT LAKES AND HEADING EAST...OR A BIT FURTHER NORTH AND STILL PARKED/ YET EITHER WAY IT LOOKS RATHER TROUGHY AND UNSETTLED WITH CYCLONIC FLOW OVER OUR REGION. SO AFTER BRIEFLY MILDER CONDITIONS TUESDAY...WE SHOULD TREND BACK TO NEAR CLIMATOLOGY FOR TEMPERATURES WEDNESDAY-THURSDAY. IF THE UPPER LOW SHIFTS EAST AS PER ECMWF...POSSIBLY A LITTLE COOLER THAN CLIMATOLOGY. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... SFC TROF IS MOVING THROUGH NRN PA AT 18Z WITH LOW LEVEL DRY AIR ADVECTION BEHIND BOUNDARY. MVFR/LOW MVFR CIGS WILL IMPROVE TO VFR BY LATE AFTERNOON WITH SKIES EXPECTED TO CLEAR EARLY THIS EVENING. PATCHY FOG IS POSSIBLE OVERNIGHT DUE TO LIGHT WINDS AND WET GROUND BUT MIST IS ONLY INCLUDED IN THE KRME TAF BETWEEN 09Z-13Z DUE TO LIGHT EASTERLY FLOW. ON SATURDAY JUST SCT CLOUDS AROUND 4K FT. W/NW WINDS AROUND 10 KNOTS BECOMING LIGHT AND VARIABLE THIS EVENING THEN NW ON SATURDAY AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS. .OUTLOOK... SAT NIGHT THRU SUN...VFR. SUN NGT-WED...RESTRICTIONS IN -RA...ESP. SUN NGT-MON NGT. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJN NEAR TERM...DJN SHORT TERM...DGM LONG TERM...MDP/PCF AVIATION...RRM
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1030 AM MDT FRI APR 17 2015 .UPDATE... ISSUED AT 1022 AM MDT FRI APR 17 2015 UPPER LOW CONTINUES TO CHURN OVER THE FOUR CORNERS REGION WITH BANDS OF LIGHT RAIN MOVING NORTHWEST THROUGH NEBRASKA AND JUST EDGING INTO FAR SOUTHWEST SOUTH DAKOTA. EXPECT THESE BANDS OF LIGHT RAIN TO CONTINUE TO MOVE INTO FAR SOUTHERN PORTIONS OF SOUTH DAKOTA WITH RAIN EVENTUALLY MOVING NORTH TO THE INTERSTATE 90 CORRIDOR BY LATE THIS AFTERNOON. MADE MINOR ADJUSTMENTS TO THE PROGRESSION OF RAIN NORTHWARD - SLOWING IT DOWN...AND REMOVED MENTION OF ISOLATED THUNDER THROUGH LATE AFTERNOON...AS IT LOOKS LIKE LAPSE RATES AND AVAILABLE ENERGY ARE MEAGER AT BEST. BETTER CHANCES FOR THUNDER ACROSS NORTHEAST WYOMING AND SOUTHERN SOUTH DAKOTA SATURDAY AFTERNOON. REMAINDER OF FORECAST IN GOOD SHAPE. UPDATES ARE OUT. && .SHORT TERM...TODAY THROUGH SATURDAY NIGHT ISSUED AT 352 AM MDT FRI APR 17 2015 CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER THE OKLAHOMA PANHANDLE AREA RIGHT NOW...WITH WEAK HIGH PRESSURE OVER EASTERN MT INTO WESTERN ND. UPPER LEVEL ANALYSIS SHOWS LARGE LOW PRESSURE SYSTEM CENTERED OVER THE FOUR CORNERS AREA...WITH STRONG JET WRAPPING AROUND THE SOUTHERN AND EASTERN SIDES OF THE LOW. CLOUD SHIELD TO THE NORTH AND EAST OF THE SYSTEM IS PUSHING NORTHWARD INTO SOUTHERN PARTS OF THE CWA...BUT DRYING UP AS IT MOVES INTO VERY DRY AIRMASS OVER NORTHERN PORTIONS OF THE NORTHERN PLAINS RIGHT NOW. REGIONAL RADARS SHOWING SHOWERS MOVING WEST-NORTHWEST ACROSS MUCH OF WESTERN NEB INTO SOUTHEAST WY...WITH DRY CONDITIONS PREVAILING ACROSS OUR CWA AT THE MOMENT. TEMPS CURRENTLY RANGE FROM THE LOW TO MID 30S ACROSS PORTIONS OF NORTHEAST WY...THE BLACK HILLS...AND FAR NORTHWEST SD...TO THE UPPER 40S ACROSS SOUTH CENTRAL SD. WINDS ARE VARIABLE AT LESS THAN 10 MPH. THE SYSTEM OVER THE FOUR CORNERS AREA EARLY THIS MORNING WILL MOVE SLOWLY NORTHEASTWARD ACROSS SOUTHERN AND EASTERN CO OVER THE NEXT COUPLE OF DAYS AND THEN ACCELERATE EASTWARD ACROSS THE CENTRAL PLAINS SATURDAY NIGHT INTO SUNDAY. THE EXACT TRACK AND TIMING OF THE SYSTEM IS STILL UNCERTAIN AT THIS POINT AND WILL ULTIMATELY HELP DETERMINE HOW MUCH PCPN WE GET ACROSS THE AREA...ESPECIALLY NORTHERN AND WESTERN PORTIONS OF THE CWA...WHERE AMOUNTS OF VERY LITTLE TO A HALF INCH OR MORE ARE POSSIBLE DEPENDING ON THE TRACK. ALL THE 00Z SHORT RANGE MODELS SHOW MOST OR ALL OF THE CWA RECEIVING AT LEAST A LITTLE BIT OF RAINFALL...WITH THE HIGHEST AMOUNTS GENERALLY OVER FAR SOUTHWEST INTO SOUTH CENTRAL SD. THE 00Z GFS SHOWS THE HEAVIEST PCPN FURTHER EAST TOWARD CENTRAL SD...WHILE THE OTHER MODELS GENERALLY HAVE IT OVER FAR SOUTHWEST/SOUTHERN SD. WILL LEAN THE FORECAST MORE TOWARD THE CONSENSUS AT THIS POINT AND KEEP HEAVIER PCPN AMOUNTS OVER FAR SOUTHERN SD. FORECAST CONFIDENCE IS HIGHEST RIGHT NOW ON SOUTHERN PORTIONS OF THE CWA RECEIVING THE MOST RAINFALL...AS WELL AS THE BEST CHANCES FOR RAINFALL ACROSS THE CWA BEING LATER TONIGHT INTO SATURDAY EVENING. PROJECTED RAINFALL AMOUNTS ACROSS THE CWA WILL MOSTLY BE IN THE 0.25 TO 0.75 INCH RANGE...WITH LESSER AMOUNTS LIKELY OVER FAR NORTHWESTERN PORTIONS OF THE CWA AND POSSIBLY AN INCH OR MORE OVER FAR SOUTHWEST INTO SOUTH CENTRAL SD. HOWEVER...WOULD TEND TO LEAN MORE TOWARD THE LIGHTER AMOUNTS FOR MOST AREAS AS HAS BEEN THE CASE FOR SYSTEMS OF LATE. FOR TODAY...SKIES WILL STAY MOSTLY CLOUDY ACROSS FAR SOUTHERN PORTIONS OF THE CWA...WITH CLOUDS GRADUALLY INCREASING TO THE NORTH. WITH MORE SUNSHINE...TEMPS THIS AFTERNOON WILL BE HIGHEST OVER FAR NORTHERN AND EASTERN PORTIONS OF THE CWA...WITH HIGHS RANGING FROM THE 50S OVER THE BLACK HILLS AND FAR SOUTHWEST SD TO THE MID TO UPPER 60S OVER FAR NORTHWEST INTO CENTRAL SD. WINDS WILL BECOME EAST TO NORTHEAST IN MOST AREAS BY THE AFTERNOON. CHANCES FOR SHOWERS WILL MAINLY BE CONFINED TO SOUTHERN SD TODAY...WITH THE BEST CHANCES IN THE AFTERNOON. CAN NOT RULE OUT A THUNDERSTORM OR TWO ACROSS SOUTHERN AREAS AS WELL THIS AFTERNOON. AS THE UPPER LOW MOVES ACROSS CO TONIGHT AND SATURDAY...LOW LEVEL MOISTURE AND UPPER LEVEL ENERGY WILL EXPAND NORTHWARD INTO THE NORTHERN PLAINS...ESPECIALLY LATER TONIGHT AND SATURDAY. SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED ACROSS THE AREA. THE MOST WIDESPREAD COVERAGE OF SHOWERS SHOULD BE ON SATURDAY...SO WILL GO WITH LIKELY POPS ACROSS MOST OF THE CWA. WITH THE LOW STAYING FAR ENOUGH SOUTH OF THE CWA...TEMPS WILL STAY WARM ENOUGH FOR MOSTLY RAIN ACROSS EVEN THE BLACK HILLS...BUT COULD SEE A MIX OVER THE HIGHEST ELEVATIONS...MAINLY LATE TONIGHT/EARLY SATURDAY AND THEN SATURDAY NIGHT WHEN THE SYSTEM EXITS. A COLD FRONT WILL TRACK ACROSS THE CWA LATE SATURDAY AND SATURDAY NIGHT...HELPING TO PUSH THE SYSTEM OUT OF THE REGION...BUT WILL BRING GUSTY WINDS ACROSS THE AREA INTO SUNDAY. .LONG TERM...SUNDAY THROUGH THURSDAY ISSUED AT 352 AM MDT FRI APR 17 2015 BLOCKED FLOW TO DEVELOP OVER THE WESTERN ATLANTIC AND EASTERN NOAM...WHICH WILL SET THE STAGE FOR WESTERN NOAM RIDING AND POTENTIAL REX TYPE BLOCKING OVER THE WESTERN CONUS. THIS WILL SUPPORT A LOW CONFIDENCE FLOW REGIME AS FORECAST MODELS WILL CONTINUALLY ADJUST TO THE LATEST OBS GIVEN TYPICAL POOR MODEL PERFORMANCE IN THESE PATTERNS. GENERALLY DRY CONDS CAN BE EXPECTED GIVEN THE REGION/S PROXY TO THE EASTERN NOAM UPPER TROUGH. A WEAK SIGNAL FOR PRECIP DOES REMAIN TOWARD THE END OF THE PERIOD WHEN FORECAST MODELS TRY TO ADVECT A WANDERING UPPER TROUGH EAST. HOWEVER...AS ALREADY STATED...LOW CONFIDENCE PER FLOW DETAILS LENDS ONLY A 20 POP AT BEST...WITH DRY THE LIKELY SCENARIO GIVEN THE PATTERN. GIVEN STRONG INFLUENCE EXPECTED OF THE EVENTUAL EASTERN CONUS UPPER LOW...EXPECT TEMPS TO BE NEAR OR SLIGHTLY BELOW SEASONAL NORMS IN THE MAJORITY OF THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 538 AM MDT FRI APR 17 2015 VFR CONDS WILL PREVAIL MOST PLACES IN THE PERIOD. A SLOW MOVING UPPER LOW WILL SLIDE NE AND BRING MVFR CONDS IN RAIN TO MAINLY EXTREME SW SD TODAY. MVFR CONDS WILL SPREAD NORTH TONIGHT...AFFECTING THE RAP TERMINAL BY LATE IN THE PERIOD...WITH SCT IFR CIGS POSSIBLE IN THE BLACK HILLS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...15 SHORT TERM...26 LONG TERM...JC AVIATION...JC
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
321 PM CDT FRI APR 17 2015 .SHORT TERM... DRYLINE AT 19Z EXTENDED FROM JUST WEST OF SILVERTON SOUTH TO WHITE RIVER LAKE AND NEAR LAKE ALAN HENRY. THIS BOUNDARY HAS BEEN FORCED WEST ALL DAY BY CONVECTIVE OUTFLOWS FARTHER EAST AND RECENT RUNS OF THE RUC HAVE THE DRYLINE ARRIVING ALONG INTERSTATE 27 BY THIS EVENING...PERHAPS MUCH SOONER. INSTABILITY-WISE...A NARROW AXIS OF SBCAPE AROUND 1000 J/KG MAY FULFILL SOME TSTORMS ALONG AND EAST OF THE DRYLINE THROUGH THE EVENING...BUT VISUAL TRENDS OF TOWERING AND MODERATE CU SUGGEST DEEPER ASCENT IS LACKING. WATER VAPOR IMAGERY INDICATE THIS AREA IS BATTLING SUBSIDENCE ALOFT DUE TO AN AXIS OF PERSISTENT DEEP CONVECTION 60-100 MILES FARTHER EAST. BECAUSE OF THIS AND LIMITED NWP SUPPORT...POPS HAVE BEEN SCALED BACK TO SLIGHT CHANCE FOR MOST AREAS OFF THE CAPROCK. AS THE FOUR CORNERS LOW BEGINS LIFTING NORTHEAST TONIGHT...LOWER TROPOSPHERIC WINDS WILL VEER MORE WESTERLY ACROSS THE WESTERN HALF OF THE CWA AND HELP TO NUDGE THE DRYLINE EASTWARD BEFORE DAYBREAK SAT. MODELS AGREE THE DRYLINE WILL MIX OUT OF OUR EASTERN ZONES BY MIDDAY AHEAD OF BREEZY SW WINDS...BUT ANY DISRUPTION TO THIS SUCH AS WE SAW TODAY WITH CONVECTIVE OUTFLOWS COULD SUPPORT A MORE WESTERLY DRYLINE LOCATION AND NECESSITATE MODIFICATIONS TO OUR DRY FORECAST FOR SATURDAY. WHEREVER THE DRYLINE ENDS UP...DEEP CONVECTION SHOULD EASILY UNFOLD BY SAT AFTN UNDER WEAK INHIBITION...STRONGER CYCLONIC FLOW AND A FAVORABLE MID-LEVEL COLD POCKET OF -20C AT 500MB. .LONG TERM... COLD FRONT PROGGED TO MOVE THROUGH THE FCST AREA SUNDAY MORNING WITH ENOUGH COLD ADVECTION TO RESULT IN HIGHS MAINLY UPPER 60S AND LOWER 70S WHILE ALSO SCOURING LOW LEVEL MOISTURE OUT OF THE FCST AREA. MAY SEE SOME CONVECTION ATTEMPT TO DEVELOP ON THE HIGH TERRAIN OF NRN NM/SRN COLO AND BE DRIVEN TO THE SE ON NWLY UPPER FLOW...BUT WITH DRY LOW LEVELS WOULD EXPECT IT TO HAVE A HARD TIME GETTING THIS FAR TO THE SE. SITUATION CHANGES SOME MONDAY WHEN SOUTH AND SE WINDS BEGIN TO BRING MOISTURE BACK INTO THE AREA. LOOKS LIKE HIGH TERRAIN CONVECTION WILL HAVE A BETTER CHANCE OF MOVING THROUGH THE PANHANDLE AND INTO NRN PARTS OF THE FCST AREA. THE MIDDLE PART OF THE WEEK WILL THEN BE ONE WITH POSSIBILITY OF WEAKLY-FORCED DIURNAL DRYLINE STORMS WITH LOW LEVEL MOISTURE INCREASING WITH TIME...CONFLUENT FLOW ALOFT TRANSITIONING TO WEAK UPPER RIDGING. 20-30 PCT STORM CHANCES TUESDAY THROUGH FRIDAY LOOK FINE WITH THIS SYNOPTIC SETUP. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 72 40 70 40 / 10 0 0 10 TULIA 76 43 73 44 / 20 0 0 10 PLAINVIEW 77 44 73 45 / 20 0 0 0 LEVELLAND 75 43 75 46 / 10 0 0 0 LUBBOCK 78 45 76 47 / 20 0 0 0 DENVER CITY 74 44 74 47 / 0 0 0 0 BROWNFIELD 76 45 76 48 / 10 0 0 0 CHILDRESS 68 55 79 51 / 50 20 10 10 SPUR 78 53 79 50 / 40 20 0 0 ASPERMONT 74 56 81 52 / 50 20 10 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 93/07
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
636 PM EDT FRI APR 17 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD INTO THE AREA TONIGHT AND SATURDAY BRINGING DRY AND WARM WEATHER FOR THE START OF THE WEEKEND. A COMPLEX STORM SYSTEM PASSING TO THE WEST WILL RESULT IN MORE WIDESPREAD RAIN SUNDAY INTO SUNDAY NIGHT BEFORE A COLD FRONT CROSSES THE REGION WITH A CHANCE OF SHOWERS AND POTENTIALLY STRONG STORMS ON MONDAY. DRY AND COOL CONDITIONS WILL PREVAIL FOR THE MIDDLE PART OF NEXT WEEK. && .NEAR TERM /THROUGH SATURDAY/... AS OF 635 PM EDT FRIDAY... UPDATE TO REFLECT CURRENT MAINLY ISOLD COVERAGE OF SHOWERS FROM FOOTHILLS INTO SOUTHSIDE VA. INCLUDED A COUPLE HOURS OF CHC POPS ACROSS SOUTHSIDE THROUGH EARLY EVENING WITH CLUSTER OF SHOWERS THERE...AND SO FAR NOT SEEING ANY SIGNS OF EVEN INTERCLOUD LIGHTNING WITH CELLS NEAR MTV AND DAN...BUT KEEPING ISOLD THUNDER IN FCST GIVEN SBCAPES OF 500-800 J/KG....AND SOME ISOL LTG IN CELLS JUST NORTHEAST OF BUCKINGHAM COUNTY. ALL THIS ACTIVITY SHOULD SLOWLY DIMINISH AS IT DRIFTS SOUTHEASTWARD INTO FAR NORTHERN NC BY 8 OR 9PM...AND RECENT HRRR RUNS SEEM TO BE DOING A BETTER JOB CAPTURING THE SPARSITY OF THE SHALLOW CONVECTION AND WEAKENING INTO THE EVENING HOURS WITH LOSS OF HEATING. SOME OF THE MORE WIDESPREAD LIGHT RAIN OVER FAR SW NC AND UPSTATE SC WILL SLIDE TO THE NORTHEAST IN ADVANCE OF WEAK SHORT WAVE HEADING EAST OUT OF TN...BUT PREVIOUS THINKING THAT IT WILL REMAIN SOUTH OF THE FCST AREA STILL LOOKS ON TRACK. WE DO KEEP A LINGERING SLIGHT CHC POP ACROSS NW NC MTNS UNTIL A LITTLE AFTER MIDNIGHT JUST IN CASE...BUT THEN DROP ALL POPS TOWARD MORNING. PREVIOUS DISCUSSION AS OF 235 PM EDT MONDAY... AT 18Z...A WEAK SURFACE TROF WAS NOTED JUST EAST OF THE BLUE RIDGE...AND WEAK CONVERGENCE ALONG THIS BOUNDARY COMBINED WITH SOME MODEST INSTABILITY (DCAPES 500-700 J/KG) SHOULD GENERATE ISOLATED SHOWERS AND STORMS ALONG THE BLUE RIDGE AS WELL AS AREAS NORTH OF I- 64 WHERE VISIBLE SATELLITE SHOWS SOME ENHANCED CUMULUS FORMING IN ADVANCE OF A FAINT UPPER LEVEL DISTURBANCE. MESOSCALE MODELS ARE OVERDONE ON THIS COVERAGE OF THIS PRECIP...BUT GENERALLY HAVE A GOOD HANDLE ON THE LOCATION OF DEVELOPMENT. ANY ISOLATED/WIDELY SCATTERED PRECIP THAT DEVELOPS SHOULD GRADUALLY DIMINISH TONIGHT...BEFORE AN UPPER LEVEL SHORTWAVE IN WEST TENNESSEE ZIPS ACROSS NRN NC LATE TONIGHT. THIS SYSTEM WILL BRING AN INCREASE IN CLOUD COVER...ESPECIALLY ACROSS THE SOUTHERN PORTION OF OUR FORECAST AREA LATE TONIGHT...AND A FEW SHOWERS MAY BE POSSIBLE. AT THE SFC...HIGH PRESSURE WILL SLOWLY NOSE SOUTH INTO THE EASTERN OHIO VALLEY BRINGING A LIGHT NORTH WIND. A SHALLOW LAYER OF MOISTURE NEAR THE SURFACE WILL REMAIN...WHICH WILL RESULT IN POCKETS OF FOG...ESPECIALLY WHERE CLOUDS ARE ABSENT TO THE NORTH. LEANED TOWARD THE WARMER GUIDANCE VALUES WITH CLOUDS. FOR SATURDAY...HEIGHTS BUILD IN ADVANCE OF A DEEP UPPER LEVEL TROF IN THE WEST AND TEMPS SHOULD AGAIN WARM WELL INTO THE 70S AND THE 80S IN THE EAST. A WEAK LOW LEVEL EAST FLOW COMBINED WITH A NOSE OF HIGHER THETA-E AIR IN NW NC INTO FAR SW VA MAY SPARK ISOLATED SHOWERS/STORMS. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... AS OF 330 PM EDT FRIDAY... FOCUS THROUGH THIS PERIOD REMAINS ON A STRONG NEGATIVELY TILTED UPPER TROUGH PROGGED TO LIFT RAPIDLY NORTHEAST ACROSS THE REGION SUNDAY INTO EARLY MONDAY. MEANWHILE...ANTECEDENT HIGH PRESSURE WILL MOVE OFF THE MID-ATLANTIC COAST INTO A NEAR CLASSIC WEDGE POSITION. STRONG PVA/ISENTROPIC LIFT INDUCED RAINFALL INTO THE WEDGE AIR MASS WILL ENHANCE/INTENSIFY THE WEDGE SUNDAY. RAINFALL/QPF WILL BE THE MAIN CONCERN AS THE WEDGE KEEPS A VERY STABLE/COOL AIR MASS IS PLACE. MOIST SOUTHEAST...UPSLOPE FLOW ALONG THE BLUE RIDGE WILL ENHANCE RAINFALL...ESPECIALLY ACROSS WATAUGA NORTHEAST TOWARD FLOYD. AS NOTED YESTERDAY...HOWEVER...THE SYSTEM WILL REMAIN HIGHLY PROGRESSIVE...LIMITING THE PERIOD OF HEAVIER RAINFALL TO 12 HOURS OR LESS. WPC HAS PARTS OF THE NC/VA SOUTHERN VA PIEDMONT OUTLOOKED FOR EXCESSIVE RAINFALL. THE MAIN CONCERN WITHIN THIS AREA WOULD BE WATAUGA THROUGH ASHE/WILKES...WITH LESS CONCERN TOWARD THE DANVILLE AREA WHERE ANTECEDENT CONDITIONS ARE RELATIVELY DRY. IN ADDITION...THE CONVECTIVE THREAT THROUGH THE HEAVIER RAIN PERIOD AS NOTED ABOVE IS MINIMAL TO NONE...WHICH SHOULD FURTHER REDUCE THE FLASH FLOOD THREAT. WILL RE-EVALUATE AGAIN TOMORROW...BUT AT THIS POINT NO NEED FOR A FLOOD/FLASH FLOOD WATCH. ONE MAY EVENTUALLY BE NEEDED FOR A SMALL AREA INCLUDING THE NW NC MOUNTAINS AND THE ADJACENT FOOTHILLS. WENT WELL BELOW GUIDANCE ON MAX TEMPS IN THE WEDGE SUNDAY...BUT AT OR ABOVE GUIDANCE ON MONDAY IN THE WARM SECTOR. MAX TEMPS MONDAY WILL BE A GOOD 20 DEGREES WARMER IN MOST AREAS THAN ON SUNDAY. MONDAY IS A DIFFERENT STORY. A SIGNIFICANT WARM SECTOR WILL SURGE NORTHWARD INTO THE REGION MONDAY AFTERNOON BEHIND THE DEPARTING UPPER TROUGH AND AN APPROACHING STRONG COLD FRONT ASSOCIATED WITH A DEEPENING BROAD UPPER TROUGH ACROSS THE GREAT LAKES. SEVERAL OF THE MODELS CONTINUE TO ADVERTISE GOOD POTENTIAL FOR STRONG THUNDERSTORMS MONDAY AFTERNOON...WITH SIGNIFICANT SVR PARAMETER NEAR 20000 ACROSS THE PIEDMONT...CAPES NEARING 2000 J/KG WITH AT LEAST 20-30KTS OF 0-2KM LOW-LEVEL SHEAR AND LIS NEAR -4C. SPC DAY 4 OUTLOOK SUGGESTS THAT DAMAGING WINDS WOULD BE THE MAIN CONCERN WITH ANY CONVECTION...MOST LIKELY LINEAR ORIENTED...THAT DEVELOPS ALONG/IN ADVANCE OF THE COLD FRONT MONDAY AFTERNOON/EVENING. THIS ACTIVITY QUICKLY MOVES EAST OF THE REGION MON AFTERNOON. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 345 PM EDT FRIDAY... A TRANSITION TO A PATTERN MORE REMINISCENT OF WINTER CONTINUES TO BE IN THE CARDS FOR THE EARLY AND MID PART OF NEXT WEEK AS A DEEP AND BROAD UPPER TROUGH BUILDS INTO THE CENTRAL/EASTERN U.S. BY TUESDAY...500MB HEIGHTS DROP INTO THE 560DM RANGE AND 850MB TEMPS PLUNGE TOWARD THE 0C MARK ACROSS THE NORTH BY MIDWEEK. ANTICYCLONIC FLOW...A SERIES OF EMBEDDED UPPER DISTURBANCES...AND COLD ADVECTION WILL KEEP VARIABLE CLOUDINESS AND POTENTIALLY UPSLOPE SHOWERS IN PLACE ACROSS THE MOUNTAINS. THE CLOUDS AND CYCLONIC FLOW WILL HOLD MAX TEMPS INTO THE 50S AND LOWER 60S ACROSS THE MOUNTAINS THROUGH MUCH OF THE LATER HALF OF NEXT WEEK...WHILE 60S TO 70S PREVAIL TO THE EAST WITH DOWNSLOPE NORTHWEST FLOW AND SIGNIFICANTLY GREATER AMOUNTS OF SUNSHINE. AT THIS POINT A DISTURBANCE ON WED APPEARS TO BE THE MOST SIGNIFICANT IN POTENTIALLY BRINGING SHOWERS EAST OF THE MOUNTAINS. HAVE NOT INTRODUCED ANY THUNDER AT THIS POINT GIVEN THE LOW-LEVEL COLD/STABLE AIR MASS. BY MID-WEEK...THE GFS/ECMWF BEGIN TO DIVERGE ON THE OVERALL PATTERN...WITH THE ECMWF KEEPING THE DEEP UPPER TROUGH IN PLACE ACROSS THE NORTHEAST AND A STRONGER NW FLOW INTO OUR REGION AS WELL...WHILE THE GFS DEPICTS THE UPPER TROUGH LIFTING FURTHER NORTH AND PLACING A ZONAL FLOW WITH A BAROCLINIC ZONE STUCK ACROSS OUR CWA. THIS RESULTS IN SIGNIFICANT DIFFERENCES BETWEEN MOISTURE/POPS ACROSS OUR CWA BETWEEN THE TWO MODELS...WITH THE GFS VERY WET AND THE ECMWF MUCH DRIER...KEEPING THE BAROCLINIC ZONE MUCH FURTHER SOUTH. HAVE JUST ADVERTISED CHC POPS FOR NOW UNTIL A BETTER HANDLE ON THIS PATTERN AND TIMING IS OBTAINED. TEMPERATURES ARE EXPECTED TO REMAIN BELOW NORMAL THROUGH THE MID PART OF THE WEEK...GRADUALLY TRENDING CLOSER TO NORMAL BY THE END OF THE PERIOD. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... AS OF 120 PM EDT FRIDAY... VFR WITH A FEW MVFR CIGS WERE NOTED ACROSS THE REGION EARLY THIS AFTERNOON. CLOUDS SHOULD GRADUALLY SCATTERED THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING HOURS WITH LIGHT WINDS. ISOLATED SHOWERS AND THUNDERSTORMS MAY DEVELOP THIS AFTERNOON...BUT COVERAGE WILL BE VERY LIMITED AND THE CHANCES OF ONE OF THESE STRAY SHOWERS/STORMS IMPACTING A TAF SITE IS SMALL. A SHALLOW LAYER OF LOW LEVEL MOISTURE WILL REMAIN IN PLACE TONIGHT...AND WITH LIGHT WINDS...POCKETS FOG REDUCING VISIBILITIES TO IFR TO MVFR CATEGORIES WILL BE POSSIBLE LATE TONIGHT. HIGH PRESSURE BUILDS NOSING DOWN INTO OUR REGION SATURDAY...WILL USHER IN SLIGHTLY DRIER AIR ALLOWING MORNING FOG/STRATUS TO QUICKLY ERODE...BRINGING VFR CONDITIONS TO ALL AREAS BY MID-MORNING SATURDAY. EXTENDED AVIATION... A COMPLEX STORM SYSTEM WILL BEGIN TO AFFECT THE REGION LATER IN THE WEEKEND WITH A WARM FRONT BRINGING WIDESPREAD MVFR/IFR CONDITIONS IN RAIN SUNDAY/SUNDAY NIGHT FOLLOWED BY ANOTHER COLD FRONTAL PASSAGE MONDAY. THIS LIKELY TO KEEP PERIODS OF MVFR IN PLACE UNTIL THE FRONT POSSIBLY CLEARS THE REGION LATER MONDAY. VFR RETURNS LATER MONDAY NIGHT AND TUESDAY WITH HIGH PRESSURE BUILDING IN BEHIND THE FRONT WITH GOOD DRYING EXPECTED. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...PH NEAR TERM...JH/PH/SK SHORT TERM...RAB LONG TERM...RAB AVIATION...JH/PH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
108 PM CDT FRI APR 17 2015 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND SATURDAY ISSUED AT 400 AM CDT FRI APR 17 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK COLD FRONT SLOWLY MOVING TO THE SOUTHEAST OVER FAR NORTHWEST WISCONSIN. AHEAD OF THE FRONT...AREAS OF BROKEN MID-CLOUDS ARE MOVING TO THE EAST OVER CENTRAL AND NORTHERN WISCONSIN. CLEAR SKIES EXIST BEHIND THIS FRONT OVER THE NORTHERN PLAINS. MEANWHILE...SHOWERS AND THUNDERSTORMS ARE OCCURRING OVER THE CENTRAL PLAINS AHEAD OF AN UPPER LOW SPINNING OVER THE 4 CORNERS REGION. FORECAST CONCERNS INCLUDE HIGH TEMPS AND LOW HUMIDITIES FOR SATURDAY. TODAY...THE COLD FRONT WILL SLOW AS IT WEAKENS OVER THE NORTHWEST THIRD OF THE STATE. SCATTERED TO BROKEN MID-LEVEL CLOUD DECK WILL GRADUALLY DISSIPATE THROUGH THE MORNING AS SUBSIDENCE STRENGTHENS OVERHEAD. WILL STILL BE SOME RESIDUAL MOISTURE LEFT AROUND 800MB...HOWEVER...THAT WILL TURN INTO A CU FIELD BY LATE MORNING OVER CENTRAL TO NORTHEAST WISCONSIN. FAR NORTHERN WISCONSIN WILL SEE AN INFLUX OF DRIER AIR DURING THE AFTERNOON...WHICH WILL DROP HUMIDITIES INTO THE 20 TO 25 PCT RANGE. HUMIDITIES SHOULD BE ABOVE CRITICAL CRITERIA ELSEWHERE. RAISED HIGH TEMPS BASED ON 925MB TEMPS ON THE BETTER PERFORMING NAM AND ECMWF...AND MAY NOT BE HIGH ENOUGH. TEMPS TO MAX OUT TO NEAR 70 NORTH TO THE UPPER 70S IN THE WARM SPOTS. TONIGHT...THE WEAKENING FRONT WILL DROP ACROSS CENTRAL AND NORTHEAST WISCONSIN DURING THE EVENING WHILE A SECONDARY AND MORE POTENT FRONT QUICKLY MOVES SOUTH ACROSS NORTHERN AND CENTRAL WISCONSIN AFTER MIDNIGHT. BEHIND THE SECOND FRONT...WINDS WILL SHIFT TO THE NORTHEAST AND COULD GUST FOR A COUPLE HOURS TO 20 OR 25 MPH. TEMPS WILL ALSO COOL OFF QUICKLY BEHIND THE FRONT WITH LOWS FALLING INTO THE MIDDLE 30S NORTH TO THE MIDDLE 40S SOUTH. SATURDAY...CANADIAN HIGH PRESSURE WILL BUILD SOUTHEAST ACROSS THE CENTRAL GREAT LAKES. THE AIRMASS ASSOCIATED WITH THIS SURFACE HIGH IS EXCEPTIONALLY DRY (NAM 850-700MB RH FALLS TO 2 PCT!). THOUGH HIGH CLOUDS WILL BE ON THE INCREASE DURING THE AFTERNOON AHEAD OF THE CENTRAL ROCKIES UPPER LOW...SHOULD STILL SEE PLENTY OF SUNSHINE ALBEIT WITH COOLER TEMPERATURES. CRITICAL RELATIVE HUMIDITIES BETWEEN 15 TO 25 PCT WILL STILL OCCUR THOUGH NORTH AND WEST OF THE FOX VALLEY. POTENTIAL IS THERE FOR HUMIDITIES TO FALL LOWER THAN THIS IF TAPPING OCCURS INTO THIS BONE DRY AIR ALOFT. HIGHS MAINLY IN THE LOW TO MID 60S AWAY FROM LAKE MICHIGAN. .LONG TERM...SATURDAY NIGHT THROUGH THURSDAY ISSUED AT 400 AM CDT FRI APR 17 2015 500MB OPEN TROUGH WILL EVOLVE INTO A CLOSED LOW OVER THE WESTERN GREAT LAKES REGION BY EARLY NEXT WEEK. COOL CYCLONIC FLOW WILL CONTINUE FOR THE REMAINDER OF NEXT WEEK AS THE 500MB LOW MEANDERS ACROSS THE GREAT LAKES REGION/EASTERN CANADA. MODELS IN SOMEWHAT BETTER AGREEMENT TONIGHT BRINGING THE BEST CHANCE FOR RAIN SUNDAY INTO SUNDAY NIGHT. WILL CONTINUE A SMALL CHANCE OF SHOWERS AFTER MIDNIGHT ON SATURDAY NIGHT TO ACCOUNT FOR A SLIGHTLY QUICKER ARRIVAL THAT SOME OF THE MODELS ARE DEPICTING. WILL HAVE LIKELY OR LOW END CATEGORICAL CHANCES FOR RAIN ON SUNDAY. HIGH TEMPERATURES TRICKY DEPENDING ON QUICK THE STEADIER RAINS ARRIVE. IF RAIN ARRIVES EARLY IN THE DAY SUNDAY...HIGH TEMPERATURES WILL NEED TO BE LOWERED. COUNTING ON SOME DRY ON BACKSIDE OF THE RETREATING HIGH PRESSURE SYSTEM TO SLOW THE ARRIVAL OF THE RAIN ACROSS EASTERN WISCONSIN. OTHERWISE...BELOW NORMAL TEMPERATURES ARE EXPECTED FOR MUCH OF THE WEEK WITH CHANCES OF RAIN INTO THE MIDDLE OF NEXT WEEK. STILL HAVE A CHANCE OF SNOW LATE AT NIGHT OR EARLY IN THE DAY FOR EACH PERIOD FROM MONDAY NIGHT THROUGH WEDNESDAY. BY THURSDAY...UPPER LOW MAY BE FAR ENOUGH AWAY FOR JUST A SMALL CHANCE OF RAIN ACROSS THE FAR NORTH. PREVIOUS FORECAST TEMPERATURES SEEMED REASONABLE WITH ONLY MINOR CHANGES MADE IN SOME PERIODS. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 108 PM CDT FRI APR 17 2015 VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. SCATTERED TO BROKEN CUMULUS THIS AFTERNOON SHOULD DISSIPATE AROUND/SHORTLY AFTER SUNSET. A DRY COLD FRONT WILL ARRIVE LATER TONIGHT. WINDS WILL SHIFT TO THE NORTHEAST BEHIND THE FRONT...AND BECOME GUSTY FOR A FEW HOURS...ESPECIALLY IN EASTERN WISCONSIN. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......MG