Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/10/14


AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
234 PM CDT TUE JUL 8 2014 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT SHOWER AND THUNDERSTORM ACTIVITY OCCURRED ACROSS THE NORTH EARLIER TODAY AS A DECAYING MCS MOVED THROUGH CENTRAL MISSOURI. OTHER THAN A STRAY SHOWER OR TWO THIS AFTERNOON...ALL PRECIPITATION FROM THIS FEATURE IS PRETTY MUCH SAID AND DONE. ATTENTION WILL TURN BACK A WEAK COLD FRONT THAT IS ROUGHLY LOCATED FROM NORTHEAST OKLAHOMA THROUGH CENTRAL MISSOURI AND EXTENDING BACK INTO THE OHIO VALLEY. MODELS REMAIN GENERALLY CONSISTENT IN THEIR HANDLING OF A LONG WAVE TROUGH...CLEARLY VISIBLE ON MOISTURE CHANNEL IMAGERY OVER SOUTHERN QUEBEC AT THIS TIME. A SERIES OF UPPER LEVEL IMPULSES WILL HELP TO MOVE THE AFOREMENTIONED FRONT INTO THE STATE. THE HRRR ONCE AGAIN DID A GOOD JOB IN THE VERY NEAR TERM AND ONCE AGAIN THE ECMWF HAS BEEN SLIGHTLY MORE CONSISTENT VERSUS OTHER SHORT TERM MODELS AND THE FORECAST WILL BE TRENDED THIS WAY. AFOREMENTIONED BOUNDARY IS EXPECTED TO DROP INTO THE NORTHERN PART OF THE STATE THIS EVENING AND SAG TO THE SOUTH...REACHING CENTRAL SECTIONS BY MORNING. THERE ARE SOME DIFFERENCES BETWEEN THE MODELS ON WHERE THIS FRONT EVENTUALLY ENDS UP BUT CURRENT THINKING IS IT WILL REACH THE LOUISIANA BORDER LATE WEDNESDAY. AFTER STALLING BRIEFLY THE BOUNDARY WILL LIFT BACK TO THE NORTH AS A WARM FRONT AS RIDGING BEGINS TO GETS REESTABLISHED OVER THE SOUTHERN HIGH PLAINS. PRECIPITATION WILL ACCOMPANY THE BOUNDARY AS IT ADVANCES THROUGH AND THEN BACK OUT OF THE STATE. A WIDESPREAD HEAVY RAIN EVENT IS NOT EXPECTED IN SPITE OF PWATS IN EXCESS OF 1.75 INCHES POOLING ALONG THE BOUNDARY. STILL WITH THIS MUCH MOISTURE IN PLACE...LOCALIZED AMOUNTS IN EXCESS OF AN INCH CAN NEVER BE RULED OUT. TEMPERATURES CONTINUE TO RUN BELOW GUIDANCE AND WITH EXPECTED RAIN AND CLOUD COVER OVER THE NEXT FEW DAYS...WOULD EXPECT THIS CONTINUE. AS SUCH...GUIDANCE WILL BE UNDERCUT A FEW DEGREES. && .LONG TERM...SATURDAY THROUGH TUESDAY... THE INFLUENCE OF THE UPPER RIDGE WILL BEGIN LESSENING OVER THE WEEKEND ACROSS THE NATURAL STATE AS UPPER FLOW TRANSITIONS TO A MORE NWRLY FLOW OVER THE REGION. BEFORE THIS HAPPENS HOWEVER...TEMPS ON SAT WILL REMAIN WELL INTO THE MID AND UPPER 90S...WITH HEAT INDEX VALUES OVER 100 IN MANY SPOTS. EXPECT PRECIP CHANCES TO REMAIN LOW...WITH MAYBE SOME ISOLATED AFTERNOON CONVECTION ON SAT. SUN WILL ALSO REMAIN WARM...BUT COULD SEE A COUPLE DEGREES COOLER ACROSS THE AREA AS HEIGHTS ALOFT BEGIN TO FALL SOME. KEEP FORECAST DRY FOR SUN AS WELL...THOUGH THERE COULD ALSO BE SOME ISOLATED AFTERNOON CONVECTION. BETTER RAIN CHANCES WILL COME EARLY NEXT WEEK AS A COLD FRONT APPROACHES FROM THE NORTH. ALSO HAVE TEMPS COOLING WITH INCREASED PRECIP CHANCES...AND EVEN FROM NRLY FLOW BEHIND THE FRONT AT THE END OF THE FORECAST IF THE FRONT PUSHES FAR ENOUGH SOUTH BY THAT TIME. && .PRELIMINARY POINT TEMPS/POPS... BATESVILLE AR 69 87 67 89 / 50 20 10 10 CAMDEN AR 73 93 72 91 / 30 50 40 30 HARRISON AR 66 87 66 87 / 50 10 10 20 HOT SPRINGS AR 73 91 72 91 / 50 40 30 30 LITTLE ROCK AR 73 90 70 90 / 50 40 20 20 MONTICELLO AR 73 92 72 89 / 30 50 40 20 MOUNT IDA AR 73 91 71 91 / 50 40 30 30 MOUNTAIN HOME AR 65 87 66 87 / 50 10 10 10 NEWPORT AR 70 86 67 89 / 50 20 10 10 PINE BLUFF AR 73 91 72 90 / 40 50 30 20 RUSSELLVILLE AR 71 88 69 89 / 50 30 20 20 SEARCY AR 71 88 68 89 / 50 30 20 20 STUTTGART AR 73 89 70 90 / 50 40 20 20 && .LZK WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...56 / LONG TERM...62
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
138 PM PDT TUE JUL 8 2014 .SYNOPSIS... HIGH PRESSURE ANCHORED OVER THE FOUR CORNERS REGION WILL KEEP ABOVE NORMAL TEMPERATURES ACROSS THE CENTRAL CALIFORNIA INTERIOR THROUGH MUCH OF THIS WEEK. THERE WILL BE SLIGHT CHANCES OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS OVER THE SIERRA NEVADA THROUGH THURSDAY AS SOME MONSOONAL MOISTURE MOVES INTO THE AREA. && .DISCUSSION...UPPER LEVEL HIGH PRESSURE OVER THE FOUR CORNERS REGION CONTINUED TO PULL MONSOONAL MOISTURE NORTH...NOW EXTENDING INTO OREGON AND EVEN FAR SOUTHERN WASHINGTON STATE. THIS MOISTURE HELPED INITIATE AFTERNOON THUNDERSTORMS ALONG THE SIERRA CREST...MAINLY ALONG THE TULARE/FRESNO COUNTY LINE JUST EAST OF LODGEPOLE. THE HRRR AND NAM DID INDICATE THAT THE HIGHEST INSTABILITY AND MOISTURE WOULD BE NORTH OF WHERE CONVECTION INITIATED YESTERDAY. HOWEVER...THE WITH THE LACK OF INSTABILITY...MU CAPE VALUES BETWEEN 300 AND 400 J/KG...WE DID NOT EXPECT TO SEE AS MANY LIGHTNING STRIKES AS YESTERDAY. THIS HAS NOT BEEN THE CASE SO FAR...AND WE WILL BE WATCHING THE CREST CLOSELY AS THUNDERSTORMS CONTINUE TO DEVELOP AND MORE NORTH. OTHERWISE...SIGNIFICANT DIFFERENCE IN TEMPERATURES COMPARED TO 24 HOURS AGO WITH MOSTLY CLEAR SKIES OVER THE ENTIRE SJ VALLEY. SOUTH OF VISALIA...TEMPERATURES WERE NEARLY IDENTICAL COMPARED TO YESTERDAY AT THIS TIME. HOWEVER...NORTH OF VISALIA TEMPERATURES WERE RUNNING BETWEEN 5 TO 13 DEGREES WARMER COMPARED TO YESTERDAY...WITH MOST VALLEY LOCATIONS ALREADY AT THE CENTURY MARK. TEMPERATURES ARE FORECAST TO RISE ANOTHER 5 OR SO DEGREES BEFORE SUNSET. A VERY SUBTLE COOLING TREND WILL BEGIN TOMORROW AS THE UPPER LEVEL RIDGE OF HIGH PRESSURE OVER FOUR CORNERS BEGINS TO FLATTEN. THIS TREND WILL CONTINUE INTO FRIDAY...WITH EACH DAY COOLING BETWEEN 2 AND 3 DEGREES. BY FRIDAY AFTERNOON...MOST VALLEY LOCATIONS WILL RANGE FROM THE MID TO UPPER 90S...NEAR NORMAL FOR THE MIDDLE OF JULY. THUNDERSTORMS CHANCES WILL MOVE NORTHWARD WEDNESDAY INTO THURSDAY AS MONSOONAL MOISTURE SHIFTS SLIGHTLY NORTH AND EAST. WE WILL CONTINUE TO SEE AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS OVER THE SIERRA CREST ON WEDNESDAY...BUT THURSDAY WILL ONLY SEE A SLIGHT CHANCE MAINLY OVER YOSEMITE. BY FRIDAY...THE UPPER HIGH SHIFTS EAST...SHIFTING OUR MOISTURE SOURCE EAST...CUTTING OFF THUNDERSTORM CHANCES. FORECASTER CONFIDENCE IS MEDIUM TO LOW WITH THE THUNDERSTORM FORECAST AS THE FORECAST MODELS HAVE NOT DONE WELL WITH THE CONVECTIVE SITUATION THE PAST FEW DAYS. THE UPPER RIDGE WILL BEGIN TO BUILD WEST OVER THE REGION SATURDAY INTO THE FIRST PART OF NEXT WEEK...WITH TRIPLE DIGIT TEMPERATURES POSSIBLE ON SUNDAY...BUT MORE LIKELY ON MONDAY. && .AVIATION... LOCAL MVFR/IFR IN MOUNTAIN THUNDERSTORMS THROUGH 02Z WEDNESDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL OVER THE REGION DURING THE NEXT 24 HOURS. && .AIR QUALITY ISSUES... ON TUESDAY JULY 8 2014... UNHEALTHY FOR SENSITIVE GROUPS IN FRESNO AND KERN COUNTIES AND SEQUOIA NATIONAL PARK AND FOREST. FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-08 115:1905 84:1983 81:1896 51:1891 KFAT 07-09 113:1905 78:1936 81:2008 55:1983 KFAT 07-10 112:2008 81:1974 82:2008 54:1904 KBFL 07-08 114:1905 85:1983 79:1907 50:1899 KBFL 07-09 113:1905 83:1980 84:2008 52:1923 KBFL 07-10 113:1905 82:1936 85:2008 51:1914 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...RILEY AVN/FW...ANDERSEN SYNOPSIS...ANDERSEN WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
912 PM PDT MON JUL 7 2014 .UPDATE...REMOVED THUNDERSTORMS FROM THE FORECAST FOR THE REST OF TONIGHT. && .SYNOPSIS... HIGH PRESSURE ANCHORED OVER THE FOUR CORNERS REGION WILL KEEP ABOVE NORMAL TEMPERATURES ACROSS THE CENTRAL CALIFORNIA INTERIOR THROUGH MUCH OF THIS WEEK. AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE OVER THE SIERRA NEVADA THROUGH FRIDAY AS MONSOONAL MOISTURE CONTINUES OVER THE AREA. && .DISCUSSION... MONSOONAL MOISTURE BROUGHT PLENTY OF CLOUD COVER ACROSS THE CENTRAL SAN JOAQUIN VALLEY TODAY HELPING TO KEEP TEMPERATURES A FEW DEGREES COOLER. FRESNO REACHED A LATE HIGH OF 99 DEGREES... BREAKING THE 8 DAY STRING OF 100+ DEGREE DAYS. MOST VALLEY CITIES FROM HANFORD AND VISALIA NORTHWARD ALSO SAW HIGHS BELOW 100. HOWEVER...IN THE SOUTH VALLEY THERE WAS MUCH MORE SUNSHINE IT REMAINED HOT WITH BAKERSFIELD REACHING 105...MAKING IT 8 CONSECUTIVE DAYS OF 100+ THERE. AT THIS TIME IT DOES NOT APPEAR THAT WE WILL SEE AS MUCH CLOUD COVER MOVING OVER THE AREA TUESDAY. THIS WILL ALLOW TEMPERATURES TO WARM ABOVE 100 DEGREES IN MOST OF THE SAN JOAQUIN VALLEY ONCE AGAIN. ALTHOUGH A FEW LIGHT SHOWERS MAY STILL OCCUR OVER THE SIERRA TONIGHT...THUNDERSTORM ACTIVITY HAS REMAINED WELL TO OUR SOUTH AND EAST IN NEVADA. THUNDERSTORMS ARE NOT EXPECTED IN THE SIERRA FOR THE REMAINDER OF TONIGHT. WITH THE MONSOONAL MOISTURE STILL SURGING NORTHWARD...WITH LEAVE THE THREAT OF THUNDERSTORMS FOR TUESDAY BUT FEEL THE GREATER THREAT IS ONCE AGAIN TO OUR EAST WHERE THERE IS BETTER INSTABILITY. && .AVIATION... SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED OVER THE HIGH COUNTRY OF THE SOUTHERN SIERRA NEVADA FROM 20Z MON THRU 06Z TUE. LOCAL IFR CONDITIONS WILL BE POSSIBLE NEAR ANY THUNDERSTORMS THAT DEVELOP. OTHERWISE VFR CONDITIONS WILL PREVAIL OVER THE REGION DURING THE NEXT 24 HOURS. && .PREV DISC... /ISSUED 230 PM PDT MON JUL 7 2014/ ABUNDANT MONSOONAL MOISTURE CONTINUES TO STREAM NORTHWEST OVER THE REGION...BRINGING SIGNIFICANT CLOUD COVER...COOLER TEMPERATURES... VALLEY SHOWERS...AND SIERRA THUNDERSTORMS. LIGHT RAIN SHOWERS CONTINUE MAINLY NORTH OF VISALIA...WITH TRACE AMOUNTS AS FAR SOUTH AS HANFORD AND AS FAR NORTH AS ATWATER...VIA FACEBOOK AND TWITTER REPORTS. THE HRRR INDICATES THAT THESE SHOWERS WILL SHIFT NORTH INTO THE 00Z HOUR. WITH THE ADDITION OF SIGNIFICANT CLOUD COVER...DAYTIME HIGH TEMPERATURES GENERALLY FROM VISALIA NORTHWARD HAVE STRUGGLED TO WARM INTO THE 90S. THERE WERE TWO SEPARATE FORECAST UPDATES TO ACCOUNT FOR THE MUCH COOLER TEMPERATURES TODAY COMPARED TO YESTERDAY...WITH THE SECOND UPDATED LOWERING FORECAST HIGH TEMPERATURES TO JUST BELOW THE CENTURY MARK FOR THE REGION IMPACTED BY CLOUDS. SIERRA THUNDERSTORMS HAVE BEGUN TO DEVELOP NEAR THE TULARE/KERN COUNTY LINE. THESE THUNDERSTORMS ARE FORECAST TO BECOME MORE NUMEROUS INTO THE LATER AFTERNOON/EARLY EVENING HOURS AND SPREAD NORTH INTO NEAR YOSEMITE. THERE IS A SIGNIFICANT AMOUNT OF MOISTURE FOR THUNDERSTORM DEVELOPMENT...HOWEVER THERE IS LIMITED INSTABILITY. MU CAPE VALUES OVER THE CREST WILL STRUGGLE TO REACH 500 J/KG...SO AT BEST...ISOLATED THUNDERSTORMS CAN BE EXPECTED. MORE LIKELY THE REGION WILL SEE A DECENT AMOUNT OF RAIN OVER THE HIGHER ELEVATIONS. AS OF 1:30 PM...BLACKROCK IN TULARE CO HAD PICKED UP 0.09" IN THE PAST HOUR. OTHERWISE...UPPER LEVEL HIGH PRESSURE IS FORECAST TO DOMINATE THE FOUR CORNERS REGION THROUGH AT LEAST THE END OF THE WEEK...BRINGING TRIPLE DIGIT TEMPERATURES...ABOVE NORMAL FOR THE MIDDLE OF JULY. SIERRA THUNDERSTORMS WILL ALSO BE POSSIBLE THROUGH AT LEAST THE END OF THE WORK WEEK. THE MOISTURE SOURCE FOR THESE THUNDERSTORMS SHIFTS SLIGHTLY EAST THURSDAY INTO FRIDAY...RESULTING IN A LOW CONFIDENCE THUNDERSTORM FORECAST BOTH ON THURSDAY AND FRIDAY. && .AIR QUALITY ISSUES... ON TUESDAY JULY 8 2014... UNHEALTHY FOR SENSITIVE GROUPS IN FRESNO AND KERN COUNTIES AND SEQUOIA NATIONAL PARK AND FOREST. FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG && .CERTAINTY... THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM. THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM. CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL INFORMATION AND/OR TO PROVIDE FEEDBACK. && .CLIMATE... RECORDS SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR KFAT 07-07 111:1905 84:1891 76:1936 53:1903 KFAT 07-08 115:1905 84:1983 81:1896 51:1891 KFAT 07-09 113:1905 78:1936 81:2008 55:1983 KBFL 07-07 114:1905 85:1983 81:1968 46:1903 KBFL 07-08 114:1905 85:1983 79:1907 50:1899 KBFL 07-09 113:1905 83:1980 84:2008 52:1923 && .HNX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ PUBLIC...BEAN AVN/FW...DUDLEY PREV DISCUSSION...RILEY SYNOPSIS...ANDERSEN WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
912 PM MDT WED JUL 9 2014 .UPDATE... ISSUED AT 903 PM MDT WED JUL 9 2014 QUICK UPDATE TO ACCOUNT FOR THE LATEST RADAR TRENDS. CURRENTLY A BAND OF STRONG THUNDERSTORMS IS DROPPING SOUTH OUT OF CHEYENNE AND KIT CARSON COUNTIES...AND WILL DROP SOUTH ACROSS OUR FAR EASTERN PLAINS COUNTIES THROUGH 1 AM. STRONG OUTFLOW WINDS TO 50 MPH AND HALF INCH HAIL ARE POSSIBLE AS THESE STORMS DROP SOUTH. LIGHT RAINFALL WITH ISOLATED THUNDERSTORMS ARE ALSO CONTINUING OVER THE MOUNTAIN REGIONS...AND SHOULD CONTINUE TO DISSIPATE THROUGH AROUND 2 AM. MOZLEY && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 319 PM MDT WED JUL 9 2014 ANOTHER ROUND OF TSRA OVER THE AREA TODAY...THOUGH SO FAR STORMS HAVE BEEN WEAKER AND HIGHER BASED THAN YESTERDAY`S ACTIVITY...AS PRECIPITABLE WATER HAS DECREASED SIGNIFICANTLY AND LOW LEVEL MOISTURE HAS MIXED AT SOME LOCATIONS ALONG THE I-25 CORRIDOR. STILL SOME FAIRLY STRONG INSTABILITY LEFT NEAR THE KS BORDER...WHERE DEWPOINTS HAVE STAYED IN THE 50S...LEADING TO CAPES IN THE 1-2K J/KG RANGE. FOR THE REST OF THE AFTERNOON AND EARLY EVENING...EXPECT SCT TSRA TO CONTINUE OVER THE MTS...WITH A FEW STORMS DRIFTING ACROSS THE VALLEYS AND INTERSTATE 25 CORRIDOR. LAST COUPLE RUNS OF THE HRRR SUGGEST STORM INTENSITY WON`T BE PARTICULARLY STRONG...ESPECIALLY AS STORMS MOVE AWAY FROM THE HIGHER TERRAIN. STILL...COULD BE A FEW SMALL POCKETS OF BRIEF HEAVY RAIN...MAINLY NEAR THE NM BORDER WHERE INSTABILITY IS A LITTLE BETTER. OVER THE FAR EASTERN PLAINS...WILL HAVE TO WATCH FOR POTENTIAL STRONG/SEVERE CONVECTION DEVELOPING OVER NERN CO BUILDING SOUTHWARD DURING THE EVENING...AS FAIRLY STRONG SHEAR AND HEALTHY SURFACE S-SE FLOW MAY KEEP STORMS GOING PAST SUNSET. HRRR SUPPORTS THIS IDEA WITH A FEW CELLS MOVING ACROSS KIOWA/PROWERS COUNTIES 03Z-04Z. OVERNIGHT...MOST ACTIVITY WILL DIE DURING THE EVENING...THOUGH WILL KEEP SOME LOW POPS GOING OVER THE SAN JUANS WHERE MODELS SUGGEST DEEPER MOISTURE AND A FEW SHOWERS MAY LINGER PAST MIDNIGHT. ON THURSDAY...LITTLE CHANGE IN THE AIR MASS FROM TODAY...THOUGH WITH SURFACE TROUGH PUSHING SLIGHTLY EAST TOWARD THE KS BORDER SUSPECT A LITTLE BETTER MIXING WILL OCCUR ALONG AND EAST OF THE MOUNTAINS...LEADING TO WEAKER/FEWER STORMS ON THE PLAINS/I-25 CORRIDOR. MOUNTAIN ACTIVITY LOOKS LITTLE CHANGED...WITH DEEPEST MOISTURE ALONG THE CONTINENTAL DIVIDE ONCE AGAIN. MAX TEMPS WILL LIKELY CREEP UP A FEW DEGREES OVER EASTERN SECTIONS WITH BETTER MIXING...WITH READINGS NEAR OR A LITTLE OVER 100F FROM PUEBLO EASTWARD. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 319 PM MDT WED JUL 9 2014 THE WEATHER PATTERN IS EXPECTED TO CHANGE VERY LITTLE AS A RIDGE OF HIGH PRESSURE REMAINS OVER THE AREA THROUGH THE WEEKEND. MONSOON MOISTURE TRAPPED UNDER THE RIDGE WILL PROVIDE THE FUEL FOR A DAILY SHOT OF SHOWERS AND THUNDERSTORMS. CONVECTION WILL BE MAINLY DIURNAL...BUT MAY START A BIT EARLIER OVER THE HIGHER TERRAIN DURING THE LATE MORNING HRS...AS WELL AS LINGER INTO THE OVERNIGHT. CONVECTION IS FORECAST TO BE SCATTERED OVER THE MTS...LIKELY OVER THE PEAKS...AND MORE ISOLATED IN NATURE ACROSS THE PLAINS AND SAN LUIS VALLEY. THURSDAY NIGHT THROUGH SUNDAY...A SHORTWAVE PASSING TO THE NORTH LATE THU WILL PUSH A COLD FRONT DOWN INTO EASTERN CO EARLY FRI...THEN A REINFORCING BLAST OF COOLER MORE MOIST AIR COMES IN ON SAT. THIS MEANS VERY WARM TEMPS FOR THE FORECAST AREA ON FRI...NEAR NORMAL LEVELS ON SAT...THEN COOLER ON SUN. THIS WILL ALSO RESULT IN SLIGHTLY HIGHER PCPN CHANCES FOR THE E PLAINS...ESPECIALLY ALONG THE I25 CORRIDOR...FOR SAT AND SUN. MONDAY THROUGH WEDNESDAY...LONG RANGE MODELS INTRODUCE A LARGE UPPER LEVEL LOW PRESSURE SYSTEM THAT DROPS OUT OF CANADA AND HEADS TOWARDS THE GREAT LAKES REGION ON MON...THEN SWEEPS IT TOWARDS THE NEW ENGLAND STATES BY MIDWEEK. IF THIS OCCURS...IT MIGHT PUSH THE UPPER RIDGE OVER THE ROCKIES MORE TO THE SW. FOR NOW...EXPECTED DAY TO DAY CONVECTION CHANCES DO NOT SEEM TO CHANGE MUCH...SAVE FOR COOLER TEMPS ON WED. MOORE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 319 PM MDT WED JUL 9 2014 SCT TSRA OVER THE MOUNTAINS WILL PERSIST INTO THE EARLY EVENING...WITH STORMS DRIFTING ACROSS LOWER ELEVATIONS...INCLUDING ALL TAF SITES 21-02Z. IN GENERAL...WITH LESS MOISTURE TODAY TSRA SHOULD BE WEAK AND HIGHER BASED AND ONLY VERY BRIEF MVFR CONDITIONS ARE EXPECTED UNDER THE STRONGER STORMS. HAVE INCLUDED VCTS IN ALL TAFS FROM 20Z-02Z...THEN VFR CONDITIONS MOST LOCATIONS OVERNIGHT THROUGH THU MORNING. VERY SIMILAR CONDITIONS AGAIN ON THURSDAY...WITH TSRA OVER THE MOUNTAINS DRIFTING TOWARD TAF SITES AFTER 20Z. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MOZLEY SHORT TERM...PETERSEN LONG TERM...MOORE AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
340 PM MDT TUE JUL 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 339 PM MDT TUE JUL 8 2014 A HOT UPPER LEVEL HIGH REMAINS ANCHORED OVER THE FOUR CORNERS REGION WITH MONSOON MOISTURE FLOWING NORTHWARD UP OVER THE DESERT SOUTHWEST AND GREAT BASIN. SOME OF THIS MOIST AND UNSTABLE SUBTROPICAL AIR HAS WRAPPED AROUND THE TOP OF THIS NEGATIVELY TILTED RIDGE AND OVER SOUTHERN AND WESTERN PORTIONS OF COLORADO AS EVIDENT ON H20 VAPOR SATELLITE IMAGERY. MEANWHILE MID-LEVEL AIR OVER NORTHEAST SECTIONS OF THE STATE HAS DRIED SOME IN THE PAST 12 HOURS...ALTHOUGH SLIGHT COOLING WAS EVIDENT ON RAP AND ACARS SOUNDINGS OVER DENVER DURING THE PAST COUPLE OF HOURS WITH A WEAK THERMAL/SHORTWAVE TROUGH MOVING ALONG IN NORTHWEST FLOW ALOFT. CONVECTION HAS BEEN SLOW TO ORGANIZE TODAY...DUE IN PART TO WARMING ALOFT AS NOTED ABOVE AND THE STABLE POST-FRONTAL AIRMASS EAST OF THE MTNS. MID-LEVEL SUBSIDENCE ON THE BACK SIDE OF THE PASSING SHORTWAVE WAS ALSO OCCURRING OVER NORTHERN PORTIONS OF THE CWA. WHEREAS WEAKLY ASCENDING AIR WITH CONVECTION INHIBITION NEARLY GONE AHEAD OF THE SHORTWAVE COUPLED WITH STEEPENING LAPSE RATES WAS HELPING TO GENERATE SCATTERED SHOWERS/T-STORMS OVER MTN...FOOTHILL AND HIGH PARK AREAS ROUGHLY SOUTH OF I-70 AT THIS HOUR. ONLY A MATTER OF TIME BEFORE SOME OF THIS CONVECTION DRIFTS SOUTHEAST ACROSS THE SOUTHERN URBAN CORRIDOR AND PALMER DIVIDE. LATEST CAPE PLOTS INDICATE VALUES ALREADY IN THE 500-1500 J/KG RANGE OVER THE SOUTHERN FOOTHILLS...SOUTH PARK AND WESTERN SECTIONS OF THE PALMER DIVIDE. IT IS IN THIS AREA THAT THE CHANCE OF STORMS IS GREATEST...IN THE 40-50 PERCENT RANGE. THESE SAME STORMS ARE ALSO MORE LIKELY TO PRODUCE HAIL...BRIEF INTENSE RAINFALL AND GUSTY OUTFLOW WINDS. IS POSSIBLE WE COULD SEE HAIL STONES UPWARDS OF 3/4 INCH IN DIAMETER. IF IT WERE A BIT WARMER...EVEN LARGER THAN THIS. OUT ACROSS THE PLAINS A RELATIVELY COOL AND STABLE POST-FRONTAL AIRMASS HAS PRETTY MUCH CAPPED ANY CONVECTION THIS AFTERNOON. THERE/S ALWAYS A CHANCE THAT AN OUTFLOW BOUNDARY MOVING OUT FROM A T-STORM NEAR THE FOOTHILLS COULD SPARK A STORM OR TWO ON THE PLAINS...BUT THE HRRR...RUC...NAM AND THE NAM NEST AND ARI SYNTHETIC SATELLITE IMAGERY DO NOT INDICATE THIS HAPPENING. WITH THE SHORTWAVE TROUGH PASSING TO THE SOUTHEAST OF THE FORECAST AREA BY EARLY THIS EVENING...SHOULD SEE A MARKED DECREASED IS SHOWER AND STORM ACTIVITY...FAR FROM WHAT HAPPENED LAST EVENING. OVERNIGHT...SHOULD SEE SKIES CLEAR AS A DRIER AND WARMER DEEP LAYER FLOW SETS UP. ON WEDNESDAY...DAY APPEARS TO START OUT DRY WITH WESTERLY MTN TOP FLOW AND A SOUTH-SOUTHWESTERLY FLOW LOWER DOWN. THROUGH THE DAY...SHOULD SEE MOISTURE LEVELS INCREASING AGAIN AS MONSOONAL MOISTURE FLOWS IN FROM UTAH. THIS TIME...THE WEST SLOPE AND HIGHER AREAS UP ALONG THE CONTINENTAL DIVIDE WILL HAVE THE BETTER CHANCE FOR SHOWERS/T-STORMS...SOME POSSIBLY PRODUCE LOCALLY HEAVY RAINFALL AND SMALL HAIL. EAST SLOPE AREAS MAY GET INTO THE ACT BUT NOT UNTIL MID TO LATE AFTERNOON. COULD SEE A FEW STORMS MOVE OFF THE FOOTHILLS AND AS THEY DO PRODUCE OUTFLOW THAT IGNITES ADDITIONAL STORM DEVELOPMENT ON THE PLAINS. AT THIS TIME...STORM COVERAGE ON THE PLAINS DURING THE DAY DOES NOT LOOK MUCH MORE THAN ISOLATED. FINALLY TEMPERATURES ON THE PLAINS WEDNESDAY ARE PROGGED TO BE AS MUCH AS 10-12 DEGS F WARMER THAN TODAY...WITH ONLY SLIGHTLY WARMER TEMPERATURES IN THE HIGH COUNTRY. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 339 PM MDT TUE JUL 8 2014 SOME STORMS WILL BE POSSIBLE WEDNESDAY EVENING...MAINLY ALONG THE FOOTHILLS AND ACROSS THE PALMER DIVIDE WHERE MODELS SHOW CAPES AROUND 500 J/KG. PRECIPITABLE WATER VALUES RANGE FROM 0.70 INCHES ALONG THE FOOTHILLS TO AROUND TO 0.90 INCHES FAR EASTERN PLAINS... WITH 0.60 INCHES ACROSS THE MOUNTAINS. SO...BRIEF HEAVY RAIN WILL BE POSSIBLE WITH SOME OF THE STORMS. AIRMASS STABILIZES BY MIDNIGHT... SO MOST CONVECTION SHOULD END AT THAT TIME. THERE MAY BE A FEW SHOWERS OR STORMS LINGERING FAR EASTERN CORNER AND ACROSS THE HIGHER MOUNTAINS. ON THURSDAY...UPPER LEVEL RIDGE WILL BE OVER COLORADO WITH WEAKER WEST NORTHWEST FLOW ALOFT. WITH CENTER OF THE UPPER HIGH OVER NORTHERN NEW MEXICO...MAIN FLOW OF SUBTROPICAL MOISTURE TO BE ACROSS WESTERN COLORADO AND EASTERN UTAH. STILL SUFFICIENT MOISTURE ACROSS CENTRAL AND EASTERN COLORADO FOR A CHANCE OF THUNDERSTORMS BY THE AFTERNOON WITH THE BEST CHANCE ACROSS THE MOUNTAINS AND FOOTHILLS. PRECIPITABLE WATER VALUES INCREASE TO AROUND 0.70 ACROSS THE MOUNTAINS WITH READINGS RANGING FROM 0.80 ALONG THE FOOTHILLS TO OVER AN INCH FAR EASTERN PLAINS. POTENTIAL FOR STORMS TO PRODUCE BRIEF HEAVY RAIN. FAIRLY LIGHT STEERING WINDS COULD CREATE SOME LOCALIZED FLOODING PROBLEMS. FAIRLY WARM AIRMASS WITH RIDGE OVERHEAD. HIGHS IN THE LOWER AND MIDDLE 90S EXPECTED ACROSS THE PLAINS. FOR FRIDAY...UPPER RIDGE STILL OVER COLORADO WITH FLOW ALOFT MORE WESTERLY. SUBTROPICAL MOISTURE TO CONTINUE TO SPREAD NORTHWARD ACROSS WESTERN COLORADO WITH A BIT MORE MOISTURE OVER EASTERN COLORADO. THIS NOTED BY AN INCREASE IN PRECIPITABLE WATER VALUES...WITH OVER AN INCH ACROSS THE PLAINS. SUFFICIENT MOISTURE FOR A CHANCE OF THUNDERSTORMS DURING THE AFTERNOON AND EVENING. BEST CHANCE OF THUNDERSTORMS TO BE ACROSS THE MOUNTAINS AND FOOTHILLS. MODELS SHOWING A MID LEVEL DISTURBANCE MOVING ACROSS WYOMING DURING THE AFTERNOON AND EVENING. SOME INCREASE IN MID LEVEL ASCENT ACROSS THE NORTHERN BORDER...WHICH MAY HELP INCREASE THE THUNDERSTORM CHANCES NEAR THE WYOMING BORDER. STORMS TO PRODUCE BRIEF HEAVY RAINFALL...BUT APPEARS THERE WILL BE ENOUGH STORM MOTION TO KEEP ANY FLOOD THREAT MINIMAL. AIRMASS STILL FAIRLY WARM WITH HIGHS IN THE LOW AND MIDDLE 90S ACROSS THE PLAINS. ON SATURDAY: RIDGE RETROGRADES SLIGHTLY WITH NORTHWEST FLOW ALOFT ACROSS COLORADO. MAIN BATCH OF SUBTROPICAL MOISTURE MOVES ACROSS UTAH...RESULTING IN A SLIGHT DECREASE IN PRECIPITABLE WATER ACROSS COLORADO. SHOULD SEE LESS THUNDERSTORM ACTIVITY AS A RESULT...WITH THE BEST CHANCE OVER THE MOUNTAINS. AIRMASS COOLER WITH HIGHS IN THE MID 80S ACROSS THE PLAINS. FOR THE LATER DAYS...SUNDAY THROUGH TUESDAY: UPPER RIDGE ACROSS GREAT BASIN SUNDAY WITH NORTHWEST FLOW ALOFT ACROSS COLORADO. BOTH GFS AND ECMWF SHOW THE RIDGE SHIFTING EAST INTO COLORADO MONDAY AND TUESDAY. SUBTROPICAL MOISTURE TO SHIFT EAST INTO WESTERN COLORADO AS A RESULT....BRINGING A BETTER CHANCE FOR AFTERNOON AND EVENING THUNDERSTORMS ALONG WITH SLIGHTLY WARMER TEMPERATURES. && .AVIATION...(FOR THE TAFS THROUGH 00Z WEDNESDAY LATE AFTERNOON) ISSUED AT 339 PM MDT TUE JUL 8 2014 ISOLATED T-STORMS ARE EXPECTED TO TRACK SOUTHEAST ACROSS THE DENVER METRO AREA NOW THROUGH 01Z THIS EVENING. THE MAJORITY OF THESE STORMS WILL PRODUCE LITTLE MORE THAN A BRIEF LIGHT TO MODERATE RAINSHOWER...GUSTY ERRATIC OUTFLOW WINDS AND OCCASIONAL CLOUD-TO-GROUND LIGHTNING. HOWEVER STORMS CROSSING SOUTHERN AND WESTERN SECTIONS OF THE METRO AREA HAVE THE POTENTIAL TO PRODUCE SMALL HAIL AND HEAVIER RAINFALL. OVERALL...EAST- SOUTHEAST SURFACE WINDS WILL PREVAIL AT SPEEDS OF 8-14KT THROUGH EARLY EVENING...THEN THE TYPICAL DRAINAGE WIND PATTERN WILL SET UP FOR THE REMAINDER OF THE NIGHT. ON WEDNESDAY...EXPECT SOUTH- SOUTHWESTERLY WINDS UNDER 11 KTS DURING THE MORNING HRS THEN WEST- NORTHWESTERLY AT 8-14KTS IN THE AFTERNOON. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BAKER LONG TERM...D-L AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1126 PM MDT MON JUL 7 2014 .UPDATE... ISSUED AT 825 PM MDT MON JUL 7 2014 UPDATED TO INCREASE POPS ACROSS THE PALMER DIVIDE AND THE FAR SE PLAINS THIS EVENING AND OVERNIGHT. LATEST NAM IS PEGGING THE POTENTIAL FOR LOCALLY HEAVY RAINFALL ACROSS THE PIKES PEAK REGION AND LOWER EASTERN SLOPES OF THE WET MTS AND SOUTHERN SANGRE DE CRISTO MTS LATER TONIGHT...AS SFC-H7 WINDS BECOME WEAK EAST TO NORTHEAST BEHIND PASSING COLD FRONT SLIDING ACROSS NORTHEASTERN COLORADO AT THIS TIME. LATEST HIGHER RESOLUTION RAP AND HRRR ARE KEEPING SFC-H7 FLOW MORE NORTHERLY THROUGH THE OVERNIGHT AND WHICH WOULD TEND TO FAVOR THE RATON MESA REGION FOR LOCALLY HEAVY RAINFALL. WITH DEW PTS IN THE 50S TO LOWER 60S ACROSS NORTHEASTERN COLORADO...AND THE POTENTIAL FOR REDEVELOPING AND TRAINING OF STORMS ACROSS THE EASTERN MTS...THERE WILL BE AN INCREASED CONCERN FOR FLASH FLOODING ON AREA BURN SCARS THROUGH THE OVERNIGHT HOURS. UPDATE ISSUED AT 451 PM MDT MON JUL 7 2014 QUICK UPDATE TO SPREAD POPS FURTHER SOUTH ACROSS THE PLAINS WITH STORMS FIRING ON OUTFLOWS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 239 PM MDT MON JUL 7 2014 SLIGHTLY MORE CONVECTION OCCURRING THIS AFTERNOON OVER THE AREA...AS AIR MASS HAS MOISTENED SOMEWHAT OVER THE PAST 24 HRS. SOUNDINGS STILL SUGGEST DRY LOW LEVELS AND RATHER HIGH CLOUD BASES...SO SUSPECT MOST STORMS AREN`T PRODUCING MUCH RAINFALL...EVEN OVER THE HIGHER TERRAIN. SURFACE COLD FRONT ALONG/JUST SOUTH OF THE PALMER DIVIDE SHOWS UP NICELY IN RADAR/SATELLITE IMAGERY AS OF 21Z...THOUGH COOLER AIR AND STRONGER PRESSURE GRADIENT ARE STILL FAIRLY FAR TO THE NORTH...WITH WON`T ARRIVE UNTIL LATER THIS EVENING. FOR THE REMAINDER OF THE AFTERNOON INTO THE EVENING...EXPECTED ISOLATED TO SCATTERED STORMS TO CONTINUE OVER THE MOUNTAINS AND HIGH VALLEYS WITH MOST ACTIVITY ENDING BY SUNSET. OVER THE I-25 CORRIDOR AND ACROSS THE EASTERN PLAINS...COLD FRONT WILL CONTINUE TO SINK SOUTH THROUGH THE EVENING...WITH GUSTY (30-40KT) NORTH WINDS ARRIVING AROUND SUNSET AT KCOS...AND SHORTLY THERE-AFTER ALONG THE LOWER ARKANSAS VALLEY. WITH CONVERGENCE ALONG THE FRONT AND SLIGHTLY DEEPER MOISTURE PUSHING WESTWARD ONCE THE BOUNDARY PASSES...SUSPECT AT LEAST ISOLATED TSRA WILL BE POSSIBLE THROUGH 06Z-09Z ALONG AND EAST OF THE MOUNTAINS. PORTIONS OF THE PLAINS WILL LIKELY SEE SOME LOWER CLOUDS AND A FEW SPRINKLES/LIGHT SHOWERS TOWARD SUNRISE AS DEEPER MOISTURE CONTINUES TO PUSH WESTWARD BEHIND THE FRONT. ON TUESDAY...MUCH COOLER CONDITIONS OVER THE EASTERN MOUNTAINS AND PLAINS WITH HIGH TEMPS AROUND 20F LOWER THAN MON. MOUNTAINS AND HIGH VALLEYS WILL COOL SLIGHTLY WITH MORE MOISTURE...THOUGH TEMPERATURE FALLS WILL BE LESS THAN THE DRAMATIC COOLING OVER THE PLAINS. AIR MASS OVER THE MOUNTAINS AND ALONG THE I-25 CORRIDOR WILL BE CONSIDERABLY MOISTER ON TUES...WITH SCT TO NUMEROUS TSRA LIKELY DEVELOPING BY EARLY AFTERNOON. DESPITE LACK OF ANY OBVIOUS UPPER SUPPORT....SUSPECT MODELS...ESPECIALLY NAM ARE UNDER ESTIMATING AMOUNT OF INSTABILITY OVER AREA AND WILL GO WITH HIGHER POPS THAN MODEL OUTPUT SUGGESTS. WILL HAVE TO WATCH AREA BURN SCARS AS STORMS WILL BE RATHER SLOW MOVING AND COULD PRODUCE HEAVY RAIN. MAIN QUESTION FOR THE DAY IS HOW FAR EAST WILL STORMS MOVE ON TO THE PLAINS...AS AIR MASS MAY TAKE A LONG TIME TO DESTABILIZE EAST OF I- 25. WILL KEEP AT LEAST ISOLATED POPS OVER ALL THE EASTERN PLAINS...AS LIFTED INDICES WILL EVENTUALLY DROP BELOW ZERO WITH AT LEAST A FEW HUNDRED JOULES OF CAPE AVAILABLE BY LATE AFTERNOON. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 239 PM MDT MON JUL 7 2014 MODELS CONTINUE TO BE IN AGREEMENT THROUGH THE EXTENDED PERIOD WITH HIGH PRESSURE OVER THE WEST AND A TROUGH OVER THE EASTERN STATES. ACTIVE WEATHER WILL PERSIST THROUGH THE EXTENDED PERIOD WITH GENERALLY DIURNALLY DRIVEN THUNDERSTORMS. EXPECT ONGOING SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE MOUNTAINS TUESDAY EVENING...SPREADING EAST ACROSS THE PLAINS THROUGH THE OVERNIGHT HOURS. LOCALLY HEAVY RAINFALL IS POSSIBLE...ESPECIALLY OVER THE EASTERN MOUNTAINS TUESDAY EVENING. BY WEDNESDAY...HIGH PRESSURE OVER THE GREAT BASIN WILL BUILD EASTWARD INTO THE ROCKIES. LOW LEVEL FLOW IS FORECAST TO TURN MORE SOUTHWESTERLY. MODELS ARE STILL TRYING TO DEVELOP A DRYLINE TYPE FEATURE ACROSS THE FAR EASTERN PLAINS WEDNESDAY AFTERNOON. THE GFS CONTINUES TO BE THE FURTHEST EAST...WITH CONVECTION FIRING OFF ACROSS WESTERN KANSAS. THE NAM KEEP THE MOISTURE FURTHER WEST ACROSS EASTERN COLORADO...WITH WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY WEDNESDAY AFTERNOON. SHEAR IS WEAK WITH THE HIGH PRESSURE OVERHEAD...AND IF THE MOISTURE STAYS IN PLACE...ONE OR TWO STRONG STORMS ARE POSSIBLE OVER THE PLAINS WEDNESDAY AFTERNOON TO EVENING. IT WILL ALL DEPEND IF AND WHERE THE DRYLINE SETS UP. EXPECT THUNDERSTORMS TO TRACK EAST OVERNIGHT AND CLEAR THE PLAINS BY THURSDAY MORNING. THE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS COLORADO ON THURSDAY AND PERSIST THROUGH EARLY NEXT WEEK. THE MOUNTAIN AREAS OF SOUTHERN COLORADO WILL SEE DAILY AFTERNOON AND EVENING THUNDERSTORMS. ELSEWHERE...PRECIPITATION WILL DEPEND ON INDIVIDUAL DISTURBANCES MOVING NORTH OUT OF THE DESERT SOUTHWEST. MODELS SEEM TO BE IN GOOD AGREEMENT WITH DECENT WAVE MOVING NORTH SATURDAY INTO SUNDAY. BOTH DAYS WILL LIKELY SEE THE BEST POTENTIAL IN THE EXTENDED PERIOD OF SEEING WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY. MOISTURE WILL BE ADEQUATE FOR LOCALLY HEAVY RAINFALL ACROSS THE MOUNTAINS...WHICH COULD PRODUCE FLASH FLOODING ON AREA BURN SCARS. MOZLEY && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1126 PM MDT MON JUL 7 2014 COLD FRONT MOVING THROUGH PUB ATTM WILL CONTINUE TO DROP THROUGH THE SOUTHEAST PLAINS OVERNIGHT...WITH GUSTY NORTH TO NORTHEAST WINDS OF 20-30KTS AT COS AND PUB TO PERSIST THROUGH 10Z. SCATTERED SHOWERS AND THUNDSTORMS DEVELOPING BEHIND PASSING FRONT WITH BEST CHANCES OF SEEING WETTING RAIN AND MVFR CIGS AT COS THROUGH THE OVERNIGHT HOURS. MOIST UPSLOPE FLOW DEVELOPS AFT 12Z WITH MVFR CIGS DEVELOPING AT COS AND PUB AND PERSISTING THROUGH THE LATE MORNING. SCATTERED TO NUMEROUS TSRA OVER THE MOUNTAINS AFTER 18Z...POSSIBLY SPREADING OUT ACROSS A MORE STABLE ATMOSPHERE ACROSS THE I-25 CORRIDOR (COS AND PUB) AFT 20Z. MAINLY VFR CONDITIONS EXPECTED AT ALS THROUGH THE PERIOD...WITH BREEZY EASTERLY WINDS POSSIBLE AFT 10Z AS COLD FRONT BANKS UP ACROSS THE EASTERN MTS. SCATTTERED TSRA ACROSS THE MTS AFT 18Z BUT NOT ENOUGH CONFIDENCE FOR MORE THAN VCTS AT THE TERMINAL ATTM. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MW SHORT TERM...PETERSEN LONG TERM...MOZLEY AVIATION...MW
AREA FORECAST DISCUSSION
NWS ALBANY NY
755 PM EDT WED JUL 9 2014 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN TOMORROW FROM THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER. THE SURFACE HIGH WILL CONTINUE TO BRING COMFORTABLE HUMIDITY LEVELS THURSDAY NIGHT INTO FRIDAY WITH SEASONABLE TEMPERATURES. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 721 PM EDT...A SEVERE THUNDERSTORM WATCH CONTINUES FROM SCHOHARIE...ALBANY...AND RENSSELAER COUNTIES IN NY SOUTH...AND ACROSS ALL OF WRN NEW ENGLAND UNTIL 10 PM. THE CURRENT STRONG TO SEVERE CONVECTION IS FORMING INTO A LINE EXTENDING FROM BENNINGTON COUNTY IN SRN VT...SOUTHWESTWARD INTO ERN CATSKILLS AND NE PA. ONE SEVERE THUNDERSTORM DEVELOPED IN OTSEGO CTY MOVED ACROSS SCHOHARIE CTY EASTWARD INTO THE CAPITAL DISTRICT PRODUCING FAIRLY WIDESPREAD WIND DAMAGE AND SOME QUARTER SIZE HAIL. PLEASE SEE OUR LATEST LSR PRODUCTS. THE CONVECTIVE MODE CONTINUES TO TREND TO A BROKEN SQUALL LINE WITH BOWING SEGMENTS FOR DAMAGING WINDS 50 KTS AND GREATER. THE BEST SBCAPES CONTINUE TO BE SOUTH OF CAPITAL REGION IN THE 500-1000 J/KG RANGE WITH POCKETS GREATER THAN 1000 J/KG IN THE MID HUDSON VALLEY AND NW CT. THE 0-6 KM EFFECTIVE BULK SHEAR CONTINUES TO BE IN 35-45 KT RANGE. THE FRONT MOVES THROUGH EARLY THIS EVENING WITH THE SHOWERS AND THUNDERSTORMS ENDING FROM THE CAPITAL REGION SOUTH AND EAST. THE LATEST HIRES WRF AND HRRR LAYER COMP REF PRODUCT SHOWS THE SHOWERS AND TSTORMS ENDING BTWN 00Z-03Z WITH CLEARING CONDITIONS IN THE WAKE OF THE FRONTAL PASSAGE FROMM 03Z-06Z. SOME PATCHY FOG IS POSSIBLE IN THE HUDSON RIVER VALLEY...SRN DACKS...AND WRN NEW ENGLAND /ESPECIALLY NEAR THE CT RIVER VALLEY/...AND JUST WEST OF THE SRN GREENS AND BERKSHIRES. THE WINDS STAYING UP OVER THE IMMEDIATE CAPITAL DISTRICT MAY PREVENT PATCHY FOG FORMATION. SOME WEAK COLD ADVECTION WILL OCCUR IN THE WAKE OF THE FRONT. LOWS WILL BE IN THE U50S TO L60S FROM THE CAPITAL REGION SOUTH AND EAST. EXPECT MAINLY 50-55F READINGS NORTH AND WEST...WITH SOME U40S OVER THE SRN DACKS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... TOMORROW...AT THE SFC...HIGH PRESSURE WILL GRADUALLY BE BUILDING INTO THE NORTHEAST FROM THE GREAT LAKES REGION. THE LONGWAVE H500 POSITIVELY TILTED TROUGH AXIS REMAINS UPSTREAM ACCORDING TO THE GFS/ECMWF/NAM. SOME SHORT-WAVE ENERGY ROUNDING THE BASE OF THE TROUGH COUPLED WITH THE FRONTAL BOUNDARY HUNG UP NEAR SE PA/NJ AND THE DELMARVA REGION MAY ALLOW A WEAK WAVE TO MOVE ALONG IT. THIS DISTURBANCE DOES NOT APPEAR IT WILL BE FAR ENOUGH TO NORTH TO IMPACT THE AREA...EXCEPT FOR SOME CLOUDS. THE SUBSIDENCE FROM THE SFC HIGH BUILDING IN SHOULD PROMOTE PARTLY TO MOSTLY SUNNY CONDITIONS WITH HIGHS IN THE U70S TO L80S IN THE VALLEYS...AND U60S TO M70S OVER THE MTNS. THURSDAY NIGHT...HIGH PRESSURE BUILDS OVER THE REGION WITH CLEAR SKIES AND LIGHT TO CALM WINDS. SOME RADIATIONAL COOLING WILL ALLOW TEMPS TO FALL INTO THE 50S WITH COMFORTABLE HUMIDITY LEVELS. SOME MID AND U40S WILL BE POSSIBLE OVER THE SRN DACKS REGION. FRI-FRI NIGHT...HIGH PRESSURE MOVES OVER NY AND NEW ENGLAND WITH A CONTINUED STRETCH OF FAIR AND DRY WEATHER. SFC DEWPTS WILL BE MAINLY IN THE 50S. HUMIDITY LEVELS WILL BE VERY COMFORTABLE. H850 TEMPS WILL BE IN THE 12C TO 14C RANGE WITH SEASONABLE HIGH TEMPS IN THE U70S TO M80S IN THE VALLEYS...AND GENERALLY 70S OVER THE MTNS. LOWS WILL GENERALLY BE IN THE 50S TO L60S WITH SOME HIGH CLOUDS INCREASING FROM THE SOUTH AND WEST AHEAD OF A WEAK WARM FRONT....AS THE SFC HIGH DRIFTS OFFSHORE. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE FIRST HALF OF THE WEEKEND DURING THE DAY ON SATURDAY WILL FEATURE TRANQUIL WEATHER AS A ZONAL UPPER LEVEL FLOW AND A WEAK SURFACE HIGH PRESSURE WILL BE IN PLACE WITH HIGH TEMPERATURES RANGING FROM THE UPPER 70S TO MID 80S. AS WE GO FROM SUNDAY NIGHT THROUGH THE REST OF THE EXTENDED PERIOD...WE WILL BE IN ACTIVE PATTERN AS A SERIES OF UPPER LEVEL IMPULSES RIDING AROUND THE BASE OF AN UPPER LEVEL LOW WILL BE MOVING THROUGH THE REGION AS THE MAIN UPPER LEVEL FEATURES SLOWLY MOVES EAST ACROSS SOUTHERN ONTARIO NORTHEASTWARD INTO QUEBEC. A SERIES OF BOUNDARIES AND A COLD FRONT WILL MAKES ITS WAY THROUGH THE REGION AS WE GO THROUGH THE DAY ON TUESDAY WITH A SURFACE LOW THAT WILL DEVELOP IN SOUTHERN CANADA. T850 WILL BE BETWEEN 8C AND 11C FROM THE LATEST 12Z MODELS AND NUMERICAL GUIDANCE AND WITH T500 COLDER THAN -10C IN CONJUNCTION WITH DAYTIME HEATING...SHOWERS AND THUNDERSTORMS ARE POSSIBLE AS WE GO THROUGH EARLY NEXT WEEK. WITH TEMPERATURES THAT COLD ALOFT...SOME THUNDERSTORMS MAY BE CAPABLE OF PRODUCING SOME GUSTY WINDS AND HAILSTONES. WINDS WILL BE OUT OF THE SOUTHWEST THROUGHOUT THE EXTENDED PERIOD TO MORE OF A WESTERLY FLOW AS WE GO PAST TUESDAY AFTER A FRONTAL SYSTEM PASSES THROUGH. HIGH TEMPERATURES ON SUNDAY THROUGH TUESDAY WILL RANGE FROM THE MID 70S TO LOWER 80S. TEMPERATURES AFTER THE FRONTAL PASSAGE FRO THE DAY ON WEDNESDAY WILL RANGE FROM THE UPPER 60S TO NEAR 70 IN THE ADIRONDACKS TO UPPER 70S IN MID HUDSON VALLEY. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... MVFR/POSSIBLE IFR CONDITIONS ARE STILL POSSIBLE AT KPOU AND KPSF WHERE THERE IS ALSO THE POTENTIAL FOR LARGE HAIL AND STRONG WINDS. THE THREAT FOR CONVECTION HAS ALREADY MOVED PAST KGFL/KALB. LATER TONIGHT MVFR TO IFR FOG IS LIKELY AT THE TAF SITES... ESPECIALLY KALB/KGFL WHICH BOTH RECEIVED RAINFALL LATE WED AFTN AND EVE. AFTER THE FOG LIFTS THURSDAY MORNING...GENERALLY BY 11Z... EXPECT VFR CONDITIONS AT ALL THE TAF SITES THROUGH THE END OF THE TAF PERIOD AT 00Z FRIDAY. LIGHT SOUTHWEST TO WEST WINDS TO START THE TAF SITES...THEN LIGHT AND VARIABLE WINDS LATE TONIGHT AND EARLY THURSDAY MORNING...BECOMING NORTH TO NORTHWEST AT 8 KTS OR LESS ON THURSDAY. OUTLOOK... THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: LOW OPERATIONAL IMPACT. ISOLATED SHRA. SUNDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA. MONDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA. && .FIRE WEATHER... A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN TOMORROW FROM THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER...THAT WILL LAST INTO FRIDAY. THE RH VALUES WILL HAVE AN EXCELLENT RECOVERY TO 85 TO 100 PERCENT TONIGHT...THEN LOWER TO 35 TO 50 PERCENT TOMORROW AFTERNOON. ANOTHER NEAR FULL RECOVERY IS LIKELY FRIDAY MORNING WITH DEW FORMATION WITH THE RH VALUES INCREASING TO 85 TO 100 PERCENT. THE WINDS WILL SHIFT FROM THE SOUTH TO SOUTHWEST EARLY THIS EVENING TO THE WEST TO NORTHWEST AT 5 TO 15 MPH. THE WINDS WILL BE FROM THE NORTH TO NORTHWEST AT 5 TO 10 MPH ON THURSDAY...AND BECOME LIGHT AND VARIABLE IN DIRECTION AT 5 MPH OR LESS THURSDAY NIGHT. && .HYDROLOGY... NO WIDESPREAD HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS ACROSS THE HYDRO SERVICE AREA. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING RAINFALL AMOUNTS OF ONE TENTH...TO ONE THIRD OF AN INCH EARLY THIS EVENING WITH LOCALL HIGHER AMOUNTS. GENERALLY DRY CONDITIONS ARE EXPECTED FROM TONIGHT THROUGH AT LEAST EARLY SATURDAY. ANOTHER DISTURBANCE WILL BRING SOME SCATTERED SHOWERS AND THUNDERSTORMS FOR THE 2ND HALF OF THE WEEKEND INTO MONDAY WITH RAINFALL AMOUNTS IN THE TENTH TO HALF AN INCH RANGE WITH LOCALLY HIGHER AMOUNTS. SOME VERY MINOR RISES ON AREA RIVERS OR STREAMS COULD OCCUR FROM THE RECENT RAINFALL...OTHERWISE MAIN STEM RIVER LEVELS ARE EXPECTED TO REMAIN STEADY...OR FALL SLIGHTLY THROUGH SATURDAY. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...WASULA NEAR TERM...WASULA SHORT TERM...WASULA LONG TERM...LFM AVIATION...GJM FIRE WEATHER...KL/WASULA HYDROLOGY...KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
721 PM EDT WED JUL 9 2014 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN TOMORROW FROM THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER. THE SURFACE HIGH WILL CONTINUE TO BRING COMFORTABLE HUMIDITY LEVELS THURSDAY NIGHT INTO FRIDAY WITH SEASONABLE TEMPERATURES. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 721 PM EDT...A SEVERE THUNDERSTORM WATCH CONTINUES FROM SCHOHARIE...ALBANY...AND RENSSELAER COUNTIES IN NY SOUTH...AND ACROSS ALL OF WRN NEW ENGLAND UNTIL 10 PM. THE CURRENT STRONG TO SEVERE CONVECTION IS FORMING INTO A LINE EXTENDING FROM BENNINGTON COUNTY IN SRN VT...SOUTHWESTWARD INTO ERN CATSKILLS AND NE PA. ONE SEVERE THUNDERSTORM DEVELOPED IN OTSEGO CTY MOVED ACROSS SCHOHARIE CTY EASTWARD INTO THE CAPITAL DISTRICT PRODUCING FAIRLY WIDESPREAD WIND DAMAGE AND SOME QUARTER SIZE HAIL. PLEASE SEE OUR LATEST LSR PRODUCTS. THE CONVECTIVE MODE CONTINUES TO TREND TO A BROKEN SQUALL LINE WITH BOWING SEGMENTS FOR DAMAGING WINDS 50 KTS AND GREATER. THE BEST SBCAPES CONTINUE TO BE SOUTH OF CAPITAL REGION IN THE 500-1000 J/KG RANGE WITH POCKETS GREATER THAN 1000 J/KG IN THE MID HUDSON VALLEY AND NW CT. THE 0-6 KM EFFECTIVE BULK SHEAR CONTINUES TO BE IN 35-45 KT RANGE. THE FRONT MOVES THROUGH EARLY THIS EVENING WITH THE SHOWERS AND THUNDERSTORMS ENDING FROM THE CAPITAL REGION SOUTH AND EAST. THE LATEST HIRES WRF AND HRRR LAYER COMP REF PRODUCT SHOWS THE SHOWERS AND TSTORMS ENDING BTWN 00Z-03Z WITH CLEARING CONDITIONS IN THE WAKE OF THE FRONTAL PASSAGE FROMM 03Z-06Z. SOME PATCHY FOG IS POSSIBLE IN THE HUDSON RIVER VALLEY...SRN DACKS...AND WRN NEW ENGLAND /ESPECIALLY NEAR THE CT RIVER VALLEY/...AND JUST WEST OF THE SRN GREENS AND BERKSHIRES. THE WINDS STAYING UP OVER THE IMMEDIATE CAPITAL DISTRICT MAY PREVENT PATCHY FOG FORMATION. SOME WEAK COLD ADVECTION WILL OCCUR IN THE WAKE OF THE FRONT. LOWS WILL BE IN THE U50S TO L60S FROM THE CAPITAL REGION SOUTH AND EAST. EXPECT MAINLY 50-55F READINGS NORTH AND WEST...WITH SOME U40S OVER THE SRN DACKS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... TOMORROW...AT THE SFC...HIGH PRESSURE WILL GRADUALLY BE BUILDING INTO THE NORTHEAST FROM THE GREAT LAKES REGION. THE LONGWAVE H500 POSITIVELY TILTED TROUGH AXIS REMAINS UPSTREAM ACCORDING TO THE GFS/ECMWF/NAM. SOME SHORT-WAVE ENERGY ROUNDING THE BASE OF THE TROUGH COUPLED WITH THE FRONTAL BOUNDARY HUNG UP NEAR SE PA/NJ AND THE DELMARVA REGION MAY ALLOW A WEAK WAVE TO MOVE ALONG IT. THIS DISTURBANCE DOES NOT APPEAR IT WILL BE FAR ENOUGH TO NORTH TO IMPACT THE AREA...EXCEPT FOR SOME CLOUDS. THE SUBSIDENCE FROM THE SFC HIGH BUILDING IN SHOULD PROMOTE PARTLY TO MOSTLY SUNNY CONDITIONS WITH HIGHS IN THE U70S TO L80S IN THE VALLEYS...AND U60S TO M70S OVER THE MTNS. THURSDAY NIGHT...HIGH PRESSURE BUILDS OVER THE REGION WITH CLEAR SKIES AND LIGHT TO CALM WINDS. SOME RADIATIONAL COOLING WILL ALLOW TEMPS TO FALL INTO THE 50S WITH COMFORTABLE HUMIDITY LEVELS. SOME MID AND U40S WILL BE POSSIBLE OVER THE SRN DACKS REGION. FRI-FRI NIGHT...HIGH PRESSURE MOVES OVER NY AND NEW ENGLAND WITH A CONTINUED STRETCH OF FAIR AND DRY WEATHER. SFC DEWPTS WILL BE MAINLY IN THE 50S. HUMIDITY LEVELS WILL BE VERY COMFORTABLE. H850 TEMPS WILL BE IN THE 12C TO 14C RANGE WITH SEASONABLE HIGH TEMPS IN THE U70S TO M80S IN THE VALLEYS...AND GENERALLY 70S OVER THE MTNS. LOWS WILL GENERALLY BE IN THE 50S TO L60S WITH SOME HIGH CLOUDS INCREASING FROM THE SOUTH AND WEST AHEAD OF A WEAK WARM FRONT....AS THE SFC HIGH DRIFTS OFFSHORE. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE FIRST HALF OF THE WEEKEND DURING THE DAY ON SATURDAY WILL FEATURE TRANQUIL WEATHER AS A ZONAL UPPER LEVEL FLOW AND A WEAK SURFACE HIGH PRESSURE WILL BE IN PLACE WITH HIGH TEMPERATURES RANGING FROM THE UPPER 70S TO MID 80S. AS WE GO FROM SUNDAY NIGHT THROUGH THE REST OF THE EXTENDED PERIOD...WE WILL BE IN ACTIVE PATTERN AS A SERIES OF UPPER LEVEL IMPULSES RIDING AROUND THE BASE OF AN UPPER LEVEL LOW WILL BE MOVING THROUGH THE REGION AS THE MAIN UPPER LEVEL FEATURES SLOWLY MOVES EAST ACROSS SOUTHERN ONTARIO NORTHEASTWARD INTO QUEBEC. A SERIES OF BOUNDARIES AND A COLD FRONT WILL MAKES ITS WAY THROUGH THE REGION AS WE GO THROUGH THE DAY ON TUESDAY WITH A SURFACE LOW THAT WILL DEVELOP IN SOUTHERN CANADA. T850 WILL BE BETWEEN 8C AND 11C FROM THE LATEST 12Z MODELS AND NUMERICAL GUIDANCE AND WITH T500 COLDER THAN -10C IN CONJUNCTION WITH DAYTIME HEATING...SHOWERS AND THUNDERSTORMS ARE POSSIBLE AS WE GO THROUGH EARLY NEXT WEEK. WITH TEMPERATURES THAT COLD ALOFT...SOME THUNDERSTORMS MAY BE CAPABLE OF PRODUCING SOME GUSTY WINDS AND HAILSTONES. WINDS WILL BE OUT OF THE SOUTHWEST THROUGHOUT THE EXTENDED PERIOD TO MORE OF A WESTERLY FLOW AS WE GO PAST TUESDAY AFTER A FRONTAL SYSTEM PASSES THROUGH. HIGH TEMPERATURES ON SUNDAY THROUGH TUESDAY WILL RANGE FROM THE MID 70S TO LOWER 80S. TEMPERATURES AFTER THE FRONTAL PASSAGE FRO THE DAY ON WEDNESDAY WILL RANGE FROM THE UPPER 60S TO NEAR 70 IN THE ADIRONDACKS TO UPPER 70S IN MID HUDSON VALLEY. && .AVIATION /23Z WEDNESDAY THROUGH MONDAY/... MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD ENDING AT 18Z THURSDAY. THE EXCEPTIONS WILL BE POSSIBLE CONVECTION THIS AFTERNOON AND EVENING WHICH COULD PRODUCE BRIEF PERIODS OF MVFR TO IFR CONDITIONS AT THE TAF SITES. THE REGION IS ALSO IN A SLIGHT RISK FOR SEVERE TSTMS...SO THERE IS THE POTENTIAL FOR LARGE HAIL AND STRONG WINDS...BUT DUE TO THE ISOLD TO SCT NATURE OF THE CONVECTION THIS AFTN/EVE...WILL ONLY FORECAST A TEMPO GROUP FOR TSTMS BETWEEN 18Z AND 22Z WITH MVFR CONDITIONS. ANY CONVECTION WILL END BETWEEN 00Z AND 02Z THIS EVENING. LATER TONIGHT MVFR/POSSIBLY IFR FOG POSSIBLE...ESPECIALLY WHERE PCPN OCCURS THIS AFTN/EVE. THE MOST LIKELY AREA FOR MVFR/IFR FOG WILL BE KGFL. SURFACE WINDS WILL BE SOUTH TO SOUTHWEST MOST OF THE AFTN AT 8 TO 12 KTS WITH GUSTS OF 15 TO 20 KTS. THE WINDS WILL TEND TO BECOME MORE WESTERLY TOWARD SUNSET WITH THE SPEEDS DECREASING. GENERALLY LIGHT AND VARIABLE WINDS LATE TONIGHT AND EARLY THURSDAY MORNING...THEN NORTH OR NORTHWEST AT 8 KTS OR LESS ON WEDNESDAY. OUTLOOK... THURSDAY TO SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: LOW OPERATIONAL IMPACT. ISOLATED SHRA. SUNDAY TO MONDAY : MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. && .FIRE WEATHER... A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN TOMORROW FROM THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER...THAT WILL LAST INTO FRIDAY. THE RH VALUES WILL HAVE AN EXCELLENT RECOVERY TO 85 TO 100 PERCENT TONIGHT...THEN LOWER TO 35 TO 50 PERCENT TOMORROW AFTERNOON. ANOTHER NEAR FULL RECOVERY IS LIKELY FRIDAY MORNING WITH DEW FORMATION WITH THE RH VALUES INCREASING TO 85 TO 100 PERCENT. THE WINDS WILL SHIFT FROM THE SOUTH TO SOUTHWEST EARLY THIS EVENING TO THE WEST TO NORTHWEST AT 5 TO 15 MPH. THE WINDS WILL BE FROM THE NORTH TO NORTHWEST AT 5 TO 10 MPH ON THURSDAY...AND BECOME LIGHT AND VARIABLE IN DIRECTION AT 5 MPH OR LESS THURSDAY NIGHT. && .HYDROLOGY... NO WIDESPREAD HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS ACROSS THE HYDRO SERVICE AREA. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING RAINFALL AMOUNTS OF ONE TENTH...TO ONE THIRD OF AN INCH EARLY THIS EVENING WITH LOCALL HIGHER AMOUNTS. GENERALLY DRY CONDITIONS ARE EXPECTED FROM TONIGHT THROUGH AT LEAST EARLY SATURDAY. ANOTHER DISTURBANCE WILL BRING SOME SCATTERED SHOWERS AND THUNDERSTORMS FOR THE 2ND HALF OF THE WEEKEND INTO MONDAY WITH RAINFALL AMOUNTS IN THE TENTH TO HALF AN INCH RANGE WITH LOCALLY HIGHER AMOUNTS. SOME VERY MINOR RISES ON AREA RIVERS OR STREAMS COULD OCCUR FROM THE RECENT RAINFALL...OTHERWISE MAIN STEM RIVER LEVELS ARE EXPECTED TO REMAIN STEADY...OR FALL SLIGHTLY THROUGH SATURDAY. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...WASULA NEAR TERM...WASULA SHORT TERM...WASULA LONG TERM...LFM AVIATION...GJM FIRE WEATHER...KL/WASULA HYDROLOGY...KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
545 PM EDT TUE JUL 8 2014 .SYNOPSIS... A LINE OF THUNDERSTORMS WILL CROSS OUR REGION FROM WEST TO EAST THIS EVENING...POSSIBLY BRINGING SOME STRONGER WIND GUSTS...HEAVY RAINFALL...HAIL AND FREQUENT CLOUD TO GROUND LIGHTNING. THE COLD FRONT RESPONSIBLE FOR THIS LINE OF STORMS WILL CROSS OUR REGION OVERNIGHT. IT WILL TURN A LITTLE LESS HUMID WEDNESDAY...BUT A SECONDARY COLD FRONT WORKING THROUGH COULD SPARK ADDITIONAL SCATTERED AFTERNOON THUNDERSTORMS. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... AS OF 545 PM EDT...CONVECTION HAS DIMINISHED ACROSS OUR REGION AS EXPECTED. HOWEVER...TO THE WEST...A BROKEN LINE OF THUNDERSTORMS CONTINUE TO MARCH ACROSS WESTERN INTO CENTRAL NEW YORK STATE. IF THIS LINE HOLDS TOGETHER...AND IT SHOULD AS IT MOVES INTO 2500 JOULES OF INSTABILITY IN OUR REGION...IT WILL REACH OUR WESTERN AREAS BEFORE 900 PM...THE CAPITAL REGION AROUND 900 PM...AND EASTERN AREAS BEFORE MIDNIGHT. WE HAVE ISSUED A SPECIAL WEATHER STATEMENT DISCUSSING THE THREAT FOR DAMAGING WINDS...HEAVY RAINFALL...FREQUENT CLOUD TO GROUND LIGHTNING AND PERHAPS EVEN HAIL. AN UPSTREAM TROUGH CONTINUES TO DIG...THE UPPER LEVEL JETSTREAM WILL INCREASE TO OVER 100KTS AND THE REGION JUST TO OUR WEST WILL COME UNDERNEATH THE BEST JET ENTRANCE REGION...THE LINE WILL LIKELY BECOME BETTER ORGANIZED WITH SOME BOWING SEGMENTS. THE ONLY MITIGATING FACTOR FOR US IS THAT THIS LINE WILL LIKELY NOT ARRIVE UNTIL NEARLY SUNDOWN...THEREBY WE LOOSE SOME HEATING OF THE DAY. HOWEVER...EVEN WITH 1000 OR A LITTLE HIGHER SURFACE BASED CAPES...THAT SHOULD BE SUFFICIENT TO CONTINUE TO ENHANCE THE STORMS GIVEN A SOMEWHAT STRONG A LOW LEVEL JET (UP TO 50 KTS AT H850) AND STRONG UPPER LEVEL DYNAMICS. THE LATEST HRRR MODEL NOW HAS THE SOLID LINE OF STORMS WORKING INTO THE CAPITAL REGION BETWEEN 9-10 PM. BY MIDNIGHT...THE LINE OF STORMS SHOULD BE TO OUR EAST. IN ITS WAKE A COLD FRONT WILL FOLLOW...BRINGING IN SOME DRIER AIR...FIRST ALOFT...EVENTUALLY AT THE SURFACE. THERE MIGHT BE ANOTHER RENEGADE SHOWER OR THUNDERSTORM OVERNIGHT BUT THE LION SHARE OF ACTION WILL BE DONE WITH OVERNIGHT. WE MIGHT HAVE SOME PATCHES OF FOG ESPECIALLY IN AREAS WHERE THE SOUTHWEST BREEZE DIMINISHES AND GROUND IS ESPECIALLY WET FROM HEAVIER SHOWERS. LOOK FOR LOWS STILL ON THE MUGGY SIDE...GENERALLY IN THE 60S. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... ON WEDNESDAY...OUR AREA WILL STILL BE A BROAD CYCLONIC FLOW ALOFT WITH SOMEWHAT DRIER AIR (PWATS UNDER AN INCH) ACROSS OUR REGION TO START THE DAY. WITH A CYCLONIC FLOW ALOFT...AND ONE MORE COLD FRONT TO WORK THROUGH...WE STILL LOOK TO BECOME UNSETTLED ONCE AGAIN BY WEDNESDAY AFTERNOON. THERE WILL BE JUST ENOUGH INSTABILITY WITH A LITTLE MOISTURE RELOADING THAT COULD TRIGGER ANOTHER ROUND OF SCATTERED AFTERNOON THUNDERSTORMS. INSTABILITY LOOKS TO INCREASE TO ABOUT 1500 J/KG WITH LAPSE RATES UP TO 6.5 C/KM. THERE WILL ALSO BE A BRISK LOW LEVEL WIND OUT OF THE SOUTHWEST AROUND 40KTS. THUNDERSTORMS ON WEDNESDAY COULD AT THE VERY LEAST PRODUCE SOME SMALL HAIL AND GUSTY WINDS. FOR NOW...WE DID NOT INCLUDE ENHANCED WORKING IN THE GRIDS SINCE THE CONFIDENCE OF STORMS IN ONLY IN THE 30 PERCENT RANGE. HIGH TEMPERATURES ON WEDNESDAY WILL BE 80-85 HIGHER TERRAIN...75-80 ACROSS THE HIGHER TERRAIN. THE SURFACE WIND WILL BE SOUTH TO SOUTHWEST 10-15 MPH...SHIFTING TO WEST BY LATE IN THE DAY BEHIND THE COLD FRONT. ANY THUNDERSTORMS SHOULD QUICKLY DIMINISH BY WEDNESDAY EVENING. AFTER THAT IT WILL CLEAR OUT...TURNING A LITTLE COOLER AND DRIER WITH LOWS GENERALLY DIPPING INTO THE 50S. THURSDAY LOOKS LIKE A NICE WITH LOTS OF SUNSHINE...COMFORTABLE HUMIDITY (DEWPOINTS IN THE 50S) AND HIGHS AROUND 80 IN THE VALLEYS...70S HIGHER TERRAIN. THURSDAY NIGHT LOOKS CLEAR AND COOL. LOWS BACK INTO THE 50S ALBANY SOUTHWARD...MID TO UPPER 40S WELL NORTH OF THE CAPITAL REGION. FRIDAY LOOKS LIKE A NICE DAY WITH LOTS OF SUNSHINE AND CONTINUED LOWER HUMIDITY. HIGHS WILL BE 80-85 VALLEYS...75-80 HIGHER TERRAIN. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... TRANQUIL WEATHER IS EXPECTED TO CONTINUE THROUGH SATURDAY AS WARM ADVECTION INCREASES AND TEMPERATURES REACH HIGHS IN THE 80S...SOME UPPER 70S IN HIGHER TERRAIN. LOW LEVEL MOISTURE INCREASES LATER IN THE WEEKEND AND SOME FORCING ASSOCIATED WITH AN ADVANCING WARM FRONT COULD SUPPORT ISOLATED TO SCATTERED THUNDERSTORMS SATURDAY NIGHT THROUGH SUNDAY. HIGHS SUNDAY ARE EXPECTED TO BE IN THE 80S...WITH MID TO UPPER 70S IN HIGHER TERRAIN. BY SUNDAY NIGHT THROUGH TUESDAY...SOME UPPER ENERGY TRACKING SOUTHEAST OUT OF CANADA AND ITS ASSOCIATED COLD FRONT WILL APPROACH WITH INCREASING COVERAGE OF SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD AS PREFRONTAL TROUGH TYPE CONVECTION INCREASES IN THE REGION. HIGHS MONDAY IN THE 80S...WITH MID TO UPPER 70S IN HIGHER TERRAIN. HIGHS TUESDAY IN THE MID 70S TO LOWER 80S. AT THIS TIME...LONG RANGE GUIDANCE SUGGESTS A FRONTAL PASSAGE LATE TUESDAY BUT AS ALWAYS THE TIMING COULD CHANGE AS WE GET CLOSER. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... A LINE OF THUNDERSTORMS WILL LIKELY IMPACT THE TERMINALS BETWEEN 01Z AND 03Z WITH HEAVY RAINFALL...GUSTY WINDS...FREQUENT LIGHTNING AND POSSIBLE HAIL. AS OF 2150Z...DIURNAL CONVECTION HAS DIMINISHED SO WE REMOVED THE VCSH THROUGH 00Z. CONDITIONS WILL REMAIN VFR. THEN...A LINE OF SHOWERS AND THUNDERSTORMS WILL MOVE TOWARD THE TAF SITES AROUND 01Z. WE ARE CONFIDENT ENOUGH TO PLACE VCTS/THUNDER IN THE TAFS BETWEEN 01Z-04Z. FOR NOW WE CAPPED WINDS AT VRB25KT...BUT THEY COULD GUST STRONGER THAN THAT. WE KEPT CONDITIONS AT THE HIGH END OF MVFR...BUT BRIEF IFR CONDITIONS ARE POSSIBLE. THE LINE LOOKS TO MOVE EAST BY 04Z. AFTER THAT...A COLD FRONT WILL PASS...SHIFTING THE WIND AND ALLOWING FOR SLOW DRYING. THE DILEMMA IS HOW FAST THIS DRYING ARRIVES. FOR NOW...WE DID PLACE MVFR CIGS IN ALL THE TAFS (LOW MVFR AT KPSF) AND MVFR MIST AT KGFL/KPSF. VFR CONDITIONS SHOULD PREVAIL AFTER THE MORNING PEAK THROUGH THE END OF THE TAF PERIOD. THE WIND WILL BE SW OR WEST AROUND 10KTS. THERE IS A CHANCE OF ADDITIONAL THUNDERSTORMS WEDNESDAY AFTERNOON...BUT THE CHANCE WAS TOO LOW (JUST UNDER 30 PERCENT) TO PLACE IN THE TAFS AT THIS TIME. OUTLOOK... WEDNESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. THURSDAY THROUGH SATURDAY NIGHT: NO OPERATIONAL IMPACT. SUNDAY: MODERATE OPERATIONAL IMPACT. CHC OF SHRA/TSRA. && .FIRE WEATHER... A LINE OF THUNDERSTORMS WILL CROSS OUR REGION THIS EVENING WITH A LEAST A QUARTER INCH OR MORE OF RAINFALL ACROSS THE ENTIRE REGION. HOWEVER...SINCE THE RAIN WILL FALL FOR ONLY A SHORT DURATION AND AT NIGHT...DID NOT ASSIGN A WET FLAG TO OUR NFDRS. DRIER WEATHER ON WEDNESDAY WITH RH VALUES DIPPING INTO THE 40S. HOWEVER...MOSE SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED BUT NOT EVERYONE WILL LIKELY RECEIVE THEM. DRY WEATHER EXPECTED THURSDAY NIGHT THROUGH SATURDAY NIGHT WITH THE USUAL NEARLY FULL RECOVER (AND SOME DEW) AT NIGHT...AND SEASONABLE AFTER RH HUMIDITIES IN THE 30S TO 40 EACH AFTERNOON. THE CHANCE OF SHOWERS AND THUNDERSTORMS LOOKS TO BE SUNDAY PERSISTING INTO EARLY NEXT WEEK. THE SURFACE WIND WILL BE SOUTH TO SOUTHWEST TONIGHT 5-15 MPH WITH HIGHER GUSTS...SOUTHWEST TO WEST AT SIMILAR SPEEDS WEDNESDAY...BECOMING NORTHWESTERLY AT 5-15 MPH ON THURSDAY AND FRIDAY. && .HYDROLOGY... A LINE OF THUNDERSTORMS AND SHOWERS WILL HEAD ACROSS OUR REGION THIS EVENING. WHILE OVER AVERAGE RAINFALL BASINS WILL UNDER AN INCH...LOCALIZED MUCH HIGHER AMOUNTS ARE POSSIBLE...POSSIBLY LOCALLY EXCEEDING TWO INCHES. THERE IS A POTENTIAL FOR LOCALIZED FLASH FLOODING BUT NOT ENOUGH AREA TO CONSIDER A FLASH FLOOD WATCH YET. SOMEWHAT DRIER AIR WILL MOVE INTO TOMORROW...BUT THE AIR MASS LOOKS TO BE REMAIN UNSTABLE FOR ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS WEDNESDAY AFTERNOON. AT THIS POINT...WE DO NOT EXPECT ANY SIGNIFICANT HYDRO PROBLEMS OTHER THAN THE USUAL LOCALIZED PONDING OF WATER ON SOME ROADS AND AREAS OF POOR DRAINAGE. DRY WEATHER THURSDAY THROUGH SATURDAY. THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ON SUNDAY AFTERNOON. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV NEAR TERM...HWJIV SHORT TERM...HWJIV LONG TERM...NAS AVIATION...HWJIV FIRE WEATHER...HWJIV HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
215 AM CDT TUE JUL 8 2014 .DISCUSSION... 825 PM CDT A COLD FRONTAL BOUNDARY CONTINUES TO MOVE SOUTHEAST ACROSS SOUTHEAST MINNESOTA AND NORTH CENTRAL IOWA WHILE A STATIONARY BOUNDARY IS STRETCHED FROM WEST TO EAST ACROSS THE FAR SOUTHERN CWA. WATER VAPOR SHOWS AN UPPER TROUGH SWINGING SOUTHEASTWARD INTO MINNESOTA WITH SEVERAL EMBEDDED WAVES HELPING TO KICK OFF CONVECTION...WITH ONE COMPLEX OVER WEST CENTRAL MINNESOTA AND ANOTHER ALONG THE IA/MO BORDER. THE CWA IS EXPECTED TO REMAIN BETWEEN THE TWO CURRENT AREAS OF CONVECTION BUT ADDITIONAL DEVELOPMENT IS EXPECTED JUST WEST OR OVER THE AREA LATER TONIGHT AS THE FRONT AND AN UPPER WAVE PASS. LATEST GUIDANCE SUGGESTS THAT THE MID LEVEL WAVE WILL AMPLIFY BRINGING AN ATTENDANT SPEED MAX ACROSS THE AREA INTO THE OVERNIGHT HOURS. ACTIVITY ALONG THE FRONT NEAR THE IA/MN BORDER HAS BEEN FESTERING BUT RAP ANALYSIS INDICATES THAT THERE IS STRONGER AXIS OF INSTABILITY ACROSS NORTHEAST IA THAT IS UNCAPPED SO SOME ENHANCEMENT IS POSSIBLE GOING FORWARD. EVENING DVN SOUNDING SHOWS A CAP IN PLACE WITH LOCAL AIRCRAFT SOUNDINGS SHOWING A MINIMAL CAP. WOULD THINK THIS CAP WOULD ERODE WITH THE INCREASE IN MID/UPPER ASCENT INTO THE OVERNIGHT. WITH MOISTURE FLUX AND PRIMARY LOW LEVEL JET WELL SOUTH OF THE AREA HIGHLY ORGANIZED CONVECTION IS UNLIKELY ACROSS THE AREA BUT DO SEE SOME OPPORTUNITY FOR SOME LOOSELY ORGANIZED ACTIVITY OVERNIGHT...WITH EXPANSION LATE THIS EVENING BUT PROBABLY STARTING TO WANE DURING THE LATE OVERNIGHT HOURS. WILL MAINTAIN THE LIKELY POPS AFTER 06Z...WITH LOWER CHANCES JUST BEFORE 06Z IN THE NORTHWEST BASED ON LATEST TRENDS. SOME GUIDANCE CONTINUES TO SUPPORT AN NORTHWARD EXPANSION OF THE MAIN AREA OF CONVECTION TO THE SOUTH OVERNIGHT IN RESPONSE TO THE INCREASE IN THE MAIN LOW LEVEL JET SO BETTER ORGANIZED ACTIVITY IS POSSIBLE IN THE FAR SOUTH SO WILL CONTINUE TO THE HIGHEST QPF IN THAT AREA. HEAVY DOWNPOURS ARE STILL THE PRIMARY THREAT WITH SOME STRONGER WIND GUSTS POSSIBLE AS WELL...ESPECIALLY ACROSS WESTERN AND SOUTHERN AREAS. MDB //PREV DISCUSSION... 142 PM CDT TONIGHT THROUGH TUESDAY... THIS AFTERNOON SKIES HAVE BECOME P-CLOUDY ACROSS THE REGION...WITH SLIGHTLY MORE AGITATED CU FIELD OVER EASTERN COOK COUNTY STRETCHING EAST INTO NORTHWEST IN...WHERE A LAKE BREEZE HAS DEVELOPED AND CONTINUES TO DRIFT INLAND. A FEW SHOWERS/THUNDERSTORMS WERE ALSO ABLE TO DEVELOP ALONG THE LAKE BREEZE IN NORTHWEST INDIANA. GREATER INSTABILITY WAS FOCUSED FURTHER SOUTH ASSOCIATED WITH THE FRONTAL BOUNDARY THAT BROUGHT PRECIP EARLY THIS MORNING TO NORTHERN IL/NORTHWEST IN. THIS AFTN THE FRONTAL BOUNDARY WAS ORIENTED FROM NORTH CENTRAL IN STRETCHING SOUTHWEST THROUGH CENTRAL IL THEN BENDING WEST/NORTHWEST INTO EASTERN NEBRASKA. DEW POINTS BEHIND THIS FEATURE IN NORTHERN IL HAVE BEEN ABLE TO FALL OFF INTO THE LOW/MID 60S...MEANWHILE ALONG AND SOUTH OF THE BOUNDARY ABUNDANT MOISTURE REMAINS WITH DEW PTS STILL IN THE LOW/MID 70S. AFTN TEMPS WILL CONTINUE TO WARM INTO THE MID/UPR 80S. THEN THE FOCUS OVERNIGHT WILL TURN TOWARDS THE WAVE CURRENTLY LOCATED OVER NEBRASKA/SOUTH DAKOTA/SOUTHWEST MINNESOTA. GUIDANCE HAS BEEN STEADILY CONSOLIDATING TOWARDS SLIGHTLY MORE UNIFORM SOLUTION...DEVELOPING A COMPLEX AND BRINGING THE ACTIVITY EAST THEN TURNING SOUTHEAST INTO SOUTHEAST IOWA/NORTHEAST MO...THEN CLIPPING THE SOUTHERN CWFA ARND MIDNIGHT THRU DAYBREAK TUE. THE PLACEMENT OF THE LLVL JET OVERNIGHT WOULD SUGGEST THAT SOME OF THE MOISTURE COULD STILL LIFT NORTH...REACHING THE NORTHERN CWFA ARND 6Z TUE AND CONTINUE THRU ARND DAYBREAK TUE BEFORE DRYING OUT FROM WEST TO EAST TUE MORNING. MID/UPR 60S DEW-PTS WILL LIKELY ADVECT BACK NORTH...WITH THE POTENTIAL FOR SOME OF THE STORMS EASILY PRODUCING BRIEF HEAVY DOWNPOURS. IN REGARDS TO ANY STORMS REACHING SEVERE CRITERIA OVERNIGHT...THIS STILL FAVORS OUR FAR WEST/SOUTHWEST. ALTHOUGH CONFIDENCE HAS DIMINISHED MARGINALLY...GIVEN THE BETTER FOCUS APPEARING TO BE FURTHER SOUTHWEST OF THE AREA. AT THIS TIME IT APPEARS A COMPLEX OF THUNDERSTORMS WILL BE ARRIVING IN THE WEST LATE TONIGHT...THEN BEGINNING TO DECAY DURING THE MORNING HOURS FOCUSED SOUTH OF I-80. THE LOBE OF VORTICITY PROGGED BY MOST GUIDANCE HAS BEEN FOCUSED ALONG THE FRONTAL BOUNDARY...WHICH IS WHY THE CONFIDENCE IN STRONGEST ACTIVITY BEING FURTHER SOUTH REMAINS. OVERNIGHT LOWS WILL REMAIN MILD IN THE MID/UPR 60S...POSSIBLY ARND 70 CLOSER TO DOWNTOWN CHICAGO. MID-LVL TROUGH AXIS STEADILY PIVOTS SOUTHEAST FROM THE UPPER MIDWEST...ARRIVING MID-MORNING TUE. THIS WILL PUSH A COLD FRONT THRU THE FORECAST AREA...WITH FLOW TURNING WEST/NORTHWEST. 850MB THERMAL RIDGE RELAXES WITH TEMPS ARND 12-14 DEG C ARRIVING MIDDAY WITH AFTN HIGHS GENERALLY IN THE UPR 70S TO ARND 80. WITH THE COOLER AIR ALOFT...AND MID-LVL LAPSE RATES STEEPENING...SOME ISOLATED DIURNALLY DRIVEN LOW TOPPED CONVECTION IS POSSIBLE MAINLY ALONG AND EAST OF ROCKFORD TO KANKAKEE. SFC RIDGE WILL SLOWLY BUILD IN TUE NGT...WITH AN ADDTL PUSH OF DRIER AIR AND THINNING CLOUD COVER. TEMPS SHUD BE ABLE TO COOL FURTHER INTO THE 50S TO NEAR 60. CONFIDENCE...HIGH. WEDNESDAY THROUGH THURSDAY... 500MB TROUGH WILL BE OVERHEAD BY EARLY WED...AND LOOKS TO REMAIN IN PLACE THRU THUR BEFORE SLOWLY EJECTING TO THE EAST LATE THUR. SFC RIDGING CONTINUES TO BE PROGGED TO BUILD IN FROM THE WEST...AND BRING MUCH DRIER AND COOLER AIR BACK TO THE FORECAST AREA FOR MID-WEEK. TEMPS ALOFT WILL HOVER ARND 10-13 DEG C...WITH HIGHS GENERALLY IN THE UPR 70S EACH DAY. OVERNIGHT LOWS WILL BE PLEASANT...IN THE UPR 50S TO LOW 60S. FRIDAY THROUGH THE WEEKEND... MINIMAL CHANGES TO THE GOING FORECAST...WITH THE TROUGH EXITING TO THE EAST AND MID-LVL FLOW BECOMING FLAT. AS THE SFC RIDGE PUSHES EAST...LLVL FLOW TURNS SOUTHERLY AND WARM/MOIST AIR BEGINS TO ADVECT BACK ACROSS THE REGION. A WEAK WAVE PUSHES OVERHEAD FRI...WITH A QUASI-STATIONARY BOUNDARY SETTING UP FOR THE WEEKEND AND ALLOWING A SEMI ACTIVE PATTERN. TEMPS WILL RETURN TO THE LOW/MID 80S. BEYOND THE CURRENT EXTENDED PERIODS...ENSEMBLES ARE ADVERTISING A HIGH CONFIDENCE RIDGE DEVELOPING ACROSS WESTERN CANADA AND DIGGING A TROUGH INTO THE GREAT LAKES/HUDSON BAY AREA EARLY NEXT WEEK. IF THIS SCENARIO VERIFIES...TEMPS WILL COOL BACK INTO THE UPR 70S TO KICK-OFF NEXT WEEK. CONFIDENCE...HIGH. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * SHRA AND A FEW EMBEDDED THUNDERSTORMS EXPECTED OVERNIGHT. * VERY SMALL CHANCE OF A LAKE BREEZE IMPACTING THE TERMINALS LATE THIS AFTERNOON. * POSSIBLE -SHRA THIS AFTERNOON. KJB //DISCUSSION...UPDATED 06Z... THE MAIN WEATHER CONCERNS WILL BE OVER THE NEXT FEW HOURS AS SHOWERS AND THUNDERSTORMS MOVE ACROSS PORTIONS OF NORTHERN ILLINOIS AND NORTHWESTERN INDIANA. CURRENTLY RADAR IMAGERY INDICATES TWO MAIN AREAS OF CONVECTIVE ACTIVITY. THE FIRST IS GRADUALLY SLIDING EAST-SOUTHEASTWARD ACROSS SOUTH CENTRAL WISCONSIN...WITH THE SECOND AREA TO THE SOUTHWEST OF THE AREA ACROSS MISSOURI AND WEST CENTRAL ILLINOIS. IT APPEARS THE SHOWER AND THUNDERSTORM ACTIVITY TO THE NORTH MAY BEGIN TO IMPACT THE TERMINALS WITHIN THE NEXT 2 TO 3 HOURS...WITH THE SOUTHWESTERN AREA OF CONVECTION LIKELY TO REMAIN SOUTH OF THE TERMINALS. ALTHOUGH THE CONVECTION ACROSS SOUTH CENTRAL WISCONSIN HAS BEEN FRAILLY STRONG OVER THE PAST COUPLE HOURS...IT WILL LIKELY UNDERGO WEAKENING OVER THE NEXT COUPLE HOURS AS IT MOVES INTO A LESS FAVORABLE THERMODYNAMIC ENVIRONMENT ACROSS NORTHERN ILLINOIS. IT COULD EVEN LOSE MOST OF THE LIGHTNING AND THUNDER. HOWEVER...I WILL CONTINUE THE THE VCTS MENTION AS SOME THUNDER IS CERTAINLY POSSIBLE OVER THE TERMINALS. THE TIMING IN THE GOING FORECAST STILL APPEARS ON TRACK...WITH IT APPROACHING KRFD AROUND 07 UTC...AND THE EASTERN TERMINALS BETWEEN 08 AND 09 UTC. EXPECT THE ACTIVITY TO MOVE OUT OF THE REGION SHORTLY AFTER DAY BREAK. DURING THE DAY TODAY THE WINDS WILL BE A LITTLE GUSTY OUT OF THE WEST-NORTHWEST...AND THIS MAY BE ENOUGH TO PREVENT A LAKE BREEZE FROM PUSHING FAR ENOUGH INLAND TO IMPACT THE TERMINALS THIS AFTERNOON. THERE COULD BE A FEW ISOLATED SHOWERS AND PERHAPS A THUNDERSTORM ACROSS NORTHERN ILLINOIS AGAIN THIS AFTERNOON AS ANOTHER DISTURBANCE MOVES ACROSS THE AREA. HOWEVER...THIS THREAT IS TOO LOW TO INCLUDE IN THE TAF. KJB //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM-HIGH IN SHRA AT THE TERMINALS OVERNIGHT. * LOW-MEDIUM IN THUNDERSTORMS OVER THE TERMINALS OVERNIGHT. * VERY LOW THAT A LAKE BREEZE WILL IMPACT THE TERMINALS LATE THIS AFTERNOON. * LOW THAT ANY ISOLATED SHRA OR TS WILL AFFECT EITHER TERMINAL THIS AFTERNOON. KJB //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY AND THURSDAY...VFR FRIDAY THROUGH SUNDAY...GENERALLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE PERIOD. 2% && .MARINE... 215 AM CDT SURFACE LOW PRESSURE IS CURRENTLY SHIFTING EASTWARD ACROSS THE NORTHERN FRINGE OF THE LAKE EARLY THIS MORNING. THIS SYSTEM WILL ALSO PUSH AN ASSOCIATED COLD FRONT EASTWARD ACROSS THE LAKE THIS MORNING. THIS WILL RESULT IN PRIMARILY A WESTERLY WIND SHIFT EARLY THIS MORNING...THEN VEERING FARTHER NORTH-NORTHWEST ACROSS THE NORTHERN HALF OF THE LAKE BY THIS AFTERNOON. HIGH PRESSURE IS EXPECTED TO GRADUALLY SHIFT EASTWARD NEAR THE SOUTHERN END OF LAKE MICHIGAN BY WEDNESDAY EVENING. OVERALL THIS WILL RESULT IN A LIGHT AND SOMEWHAT VARIABLE WIND FIELD ACROSS THE LAKE WEDNESDAY INTO THURSDAY. HOWEVER...LAKE BREEZE INFLUENCES WILL LIKELY LEAD TO AN ONSHORE FLOW REGIME ACROSS THE NEAR SHORE WATERS DURING THE DAY TIME HOURS WEDNESDAY AND THURSDAY. THE SURFACE HIGH IS EXPECTED TO SHIFT EASTWARD TOWARDS THE ATLANTIC COAST LATER IN THE WEEK. AS THIS OCCURS...IT SHOULD ALLOW THE FLOW TO SHIFT BACK OUT OF THE SOUTH OVER THE LAKE INTO THE WEEKEND. IN ADDITION...INCREASING MOISTURE AND ADDITIONAL WEATHER DISTURBANCES LOOK TO INCREASE THE CHANCES FOR SHOWERS AND STORMS AGAIN FOR FRIDAY AND INTO THE WEEKEND. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1233 AM CDT TUE JUL 8 2014 .DISCUSSION... 825 PM CDT A COLD FRONTAL BOUNDARY CONTINUES TO MOVE SOUTHEAST ACROSS SOUTHEAST MINNESOTA AND NORTH CENTRAL IOWA WHILE A STATIONARY BOUNDARY IS STRETCHED FROM WEST TO EAST ACROSS THE FAR SOUTHERN CWA. WATER VAPOR SHOWS AN UPPER TROUGH SWINGING SOUTHEASTWARD INTO MINNESOTA WITH SEVERAL EMBEDDED WAVES HELPING TO KICK OFF CONVECTION...WITH ONE COMPLEX OVER WEST CENTRAL MINNESOTA AND ANOTHER ALONG THE IA/MO BORDER. THE CWA IS EXPECTED TO REMAIN BETWEEN THE TWO CURRENT AREAS OF CONVECTION BUT ADDITIONAL DEVELOPMENT IS EXPECTED JUST WEST OR OVER THE AREA LATER TONIGHT AS THE FRONT AND AN UPPER WAVE PASS. LATEST GUIDANCE SUGGESTS THAT THE MID LEVEL WAVE WILL AMPLIFY BRINGING AN ATTENDANT SPEED MAX ACROSS THE AREA INTO THE OVERNIGHT HOURS. ACTIVITY ALONG THE FRONT NEAR THE IA/MN BORDER HAS BEEN FESTERING BUT RAP ANALYSIS INDICATES THAT THERE IS STRONGER AXIS OF INSTABILITY ACROSS NORTHEAST IA THAT IS UNCAPPED SO SOME ENHANCEMENT IS POSSIBLE GOING FORWARD. EVENING DVN SOUNDING SHOWS A CAP IN PLACE WITH LOCAL AIRCRAFT SOUNDINGS SHOWING A MINIMAL CAP. WOULD THINK THIS CAP WOULD ERODE WITH THE INCREASE IN MID/UPPER ASCENT INTO THE OVERNIGHT. WITH MOISTURE FLUX AND PRIMARY LOW LEVEL JET WELL SOUTH OF THE AREA HIGHLY ORGANIZED CONVECTION IS UNLIKELY ACROSS THE AREA BUT DO SEE SOME OPPORTUNITY FOR SOME LOOSELY ORGANIZED ACTIVITY OVERNIGHT...WITH EXPANSION LATE THIS EVENING BUT PROBABLY STARTING TO WANE DURING THE LATE OVERNIGHT HOURS. WILL MAINTAIN THE LIKELY POPS AFTER 06Z...WITH LOWER CHANCES JUST BEFORE 06Z IN THE NORTHWEST BASED ON LATEST TRENDS. SOME GUIDANCE CONTINUES TO SUPPORT AN NORTHWARD EXPANSION OF THE MAIN AREA OF CONVECTION TO THE SOUTH OVERNIGHT IN RESPONSE TO THE INCREASE IN THE MAIN LOW LEVEL JET SO BETTER ORGANIZED ACTIVITY IS POSSIBLE IN THE FAR SOUTH SO WILL CONTINUE TO THE HIGHEST QPF IN THAT AREA. HEAVY DOWNPOURS ARE STILL THE PRIMARY THREAT WITH SOME STRONGER WIND GUSTS POSSIBLE AS WELL...ESPECIALLY ACROSS WESTERN AND SOUTHERN AREAS. MDB //PREV DISCUSSION... 142 PM CDT TONIGHT THROUGH TUESDAY... THIS AFTERNOON SKIES HAVE BECOME P-CLOUDY ACROSS THE REGION...WITH SLIGHTLY MORE AGITATED CU FIELD OVER EASTERN COOK COUNTY STRETCHING EAST INTO NORTHWEST IN...WHERE A LAKE BREEZE HAS DEVELOPED AND CONTINUES TO DRIFT INLAND. A FEW SHOWERS/THUNDERSTORMS WERE ALSO ABLE TO DEVELOP ALONG THE LAKE BREEZE IN NORTHWEST INDIANA. GREATER INSTABILITY WAS FOCUSED FURTHER SOUTH ASSOCIATED WITH THE FRONTAL BOUNDARY THAT BROUGHT PRECIP EARLY THIS MORNING TO NORTHERN IL/NORTHWEST IN. THIS AFTN THE FRONTAL BOUNDARY WAS ORIENTED FROM NORTH CENTRAL IN STRETCHING SOUTHWEST THROUGH CENTRAL IL THEN BENDING WEST/NORTHWEST INTO EASTERN NEBRASKA. DEW POINTS BEHIND THIS FEATURE IN NORTHERN IL HAVE BEEN ABLE TO FALL OFF INTO THE LOW/MID 60S...MEANWHILE ALONG AND SOUTH OF THE BOUNDARY ABUNDANT MOISTURE REMAINS WITH DEW PTS STILL IN THE LOW/MID 70S. AFTN TEMPS WILL CONTINUE TO WARM INTO THE MID/UPR 80S. THEN THE FOCUS OVERNIGHT WILL TURN TOWARDS THE WAVE CURRENTLY LOCATED OVER NEBRASKA/SOUTH DAKOTA/SOUTHWEST MINNESOTA. GUIDANCE HAS BEEN STEADILY CONSOLIDATING TOWARDS SLIGHTLY MORE UNIFORM SOLUTION...DEVELOPING A COMPLEX AND BRINGING THE ACTIVITY EAST THEN TURNING SOUTHEAST INTO SOUTHEAST IOWA/NORTHEAST MO...THEN CLIPPING THE SOUTHERN CWFA ARND MIDNIGHT THRU DAYBREAK TUE. THE PLACEMENT OF THE LLVL JET OVERNIGHT WOULD SUGGEST THAT SOME OF THE MOISTURE COULD STILL LIFT NORTH...REACHING THE NORTHERN CWFA ARND 6Z TUE AND CONTINUE THRU ARND DAYBREAK TUE BEFORE DRYING OUT FROM WEST TO EAST TUE MORNING. MID/UPR 60S DEW-PTS WILL LIKELY ADVECT BACK NORTH...WITH THE POTENTIAL FOR SOME OF THE STORMS EASILY PRODUCING BRIEF HEAVY DOWNPOURS. IN REGARDS TO ANY STORMS REACHING SEVERE CRITERIA OVERNIGHT...THIS STILL FAVORS OUR FAR WEST/SOUTHWEST. ALTHOUGH CONFIDENCE HAS DIMINISHED MARGINALLY...GIVEN THE BETTER FOCUS APPEARING TO BE FURTHER SOUTHWEST OF THE AREA. AT THIS TIME IT APPEARS A COMPLEX OF THUNDERSTORMS WILL BE ARRIVING IN THE WEST LATE TONIGHT...THEN BEGINNING TO DECAY DURING THE MORNING HOURS FOCUSED SOUTH OF I-80. THE LOBE OF VORTICITY PROGGED BY MOST GUIDANCE HAS BEEN FOCUSED ALONG THE FRONTAL BOUNDARY...WHICH IS WHY THE CONFIDENCE IN STRONGEST ACTIVITY BEING FURTHER SOUTH REMAINS. OVERNIGHT LOWS WILL REMAIN MILD IN THE MID/UPR 60S...POSSIBLY ARND 70 CLOSER TO DOWNTOWN CHICAGO. MID-LVL TROUGH AXIS STEADILY PIVOTS SOUTHEAST FROM THE UPPER MIDWEST...ARRIVING MID-MORNING TUE. THIS WILL PUSH A COLD FRONT THRU THE FORECAST AREA...WITH FLOW TURNING WEST/NORTHWEST. 850MB THERMAL RIDGE RELAXES WITH TEMPS ARND 12-14 DEG C ARRIVING MIDDAY WITH AFTN HIGHS GENERALLY IN THE UPR 70S TO ARND 80. WITH THE COOLER AIR ALOFT...AND MID-LVL LAPSE RATES STEEPENING...SOME ISOLATED DIURNALLY DRIVEN LOW TOPPED CONVECTION IS POSSIBLE MAINLY ALONG AND EAST OF ROCKFORD TO KANKAKEE. SFC RIDGE WILL SLOWLY BUILD IN TUE NGT...WITH AN ADDTL PUSH OF DRIER AIR AND THINNING CLOUD COVER. TEMPS SHUD BE ABLE TO COOL FURTHER INTO THE 50S TO NEAR 60. CONFIDENCE...HIGH. WEDNESDAY THROUGH THURSDAY... 500MB TROUGH WILL BE OVERHEAD BY EARLY WED...AND LOOKS TO REMAIN IN PLACE THRU THUR BEFORE SLOWLY EJECTING TO THE EAST LATE THUR. SFC RIDGING CONTINUES TO BE PROGGED TO BUILD IN FROM THE WEST...AND BRING MUCH DRIER AND COOLER AIR BACK TO THE FORECAST AREA FOR MID-WEEK. TEMPS ALOFT WILL HOVER ARND 10-13 DEG C...WITH HIGHS GENERALLY IN THE UPR 70S EACH DAY. OVERNIGHT LOWS WILL BE PLEASANT...IN THE UPR 50S TO LOW 60S. FRIDAY THROUGH THE WEEKEND... MINIMAL CHANGES TO THE GOING FORECAST...WITH THE TROUGH EXITING TO THE EAST AND MID-LVL FLOW BECOMING FLAT. AS THE SFC RIDGE PUSHES EAST...LLVL FLOW TURNS SOUTHERLY AND WARM/MOIST AIR BEGINS TO ADVECT BACK ACROSS THE REGION. A WEAK WAVE PUSHES OVERHEAD FRI...WITH A QUASI-STATIONARY BOUNDARY SETTING UP FOR THE WEEKEND AND ALLOWING A SEMI ACTIVE PATTERN. TEMPS WILL RETURN TO THE LOW/MID 80S. BEYOND THE CURRENT EXTENDED PERIODS...ENSEMBLES ARE ADVERTISING A HIGH CONFIDENCE RIDGE DEVELOPING ACROSS WESTERN CANADA AND DIGGING A TROUGH INTO THE GREAT LAKES/HUDSON BAY AREA EARLY NEXT WEEK. IF THIS SCENARIO VERIFIES...TEMPS WILL COOL BACK INTO THE UPR 70S TO KICK-OFF NEXT WEEK. CONFIDENCE...HIGH. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * SHRA AND A FEW EMBEDDED THUNDERSTORMS EXPECTED OVERNIGHT. * VERY SMALL CHANCE OF A LAKE BREEZE IMPACTING THE TERMINALS LATE THIS AFTERNOON. * POSSIBLE -SHRA THIS AFTERNOON. KJB //DISCUSSION...UPDATED 06Z... THE MAIN WEATHER CONCERNS WILL BE OVER THE NEXT FEW HOURS AS SHOWERS AND THUNDERSTORMS MOVE ACROSS PORTIONS OF NORTHERN ILLINOIS AND NORTHWESTERN INDIANA. CURRENTLY RADAR IMAGERY INDICATES TWO MAIN AREAS OF CONVECTIVE ACTIVITY. THE FIRST IS GRADUALLY SLIDING EAST-SOUTHEASTWARD ACROSS SOUTH CENTRAL WISCONSIN...WITH THE SECOND AREA TO THE SOUTHWEST OF THE AREA ACROSS MISSOURI AND WEST CENTRAL ILLINOIS. IT APPEARS THE SHOWER AND THUNDERSTORM ACTIVITY TO THE NORTH MAY BEGIN TO IMPACT THE TERMINALS WITHIN THE NEXT 2 TO 3 HOURS...WITH THE SOUTHWESTERN AREA OF CONVECTION LIKELY TO REMAIN SOUTH OF THE TERMINALS. ALTHOUGH THE CONVECTION ACROSS SOUTH CENTRAL WISCONSIN HAS BEEN FRAILLY STRONG OVER THE PAST COUPLE HOURS...IT WILL LIKELY UNDERGO WEAKENING OVER THE NEXT COUPLE HOURS AS IT MOVES INTO A LESS FAVORABLE THERMODYNAMIC ENVIRONMENT ACROSS NORTHERN ILLINOIS. IT COULD EVEN LOSE MOST OF THE LIGHTNING AND THUNDER. HOWEVER...I WILL CONTINUE THE THE VCTS MENTION AS SOME THUNDER IS CERTAINLY POSSIBLE OVER THE TERMINALS. THE TIMING IN THE GOING FORECAST STILL APPEARS ON TRACK...WITH IT APPROACHING KRFD AROUND 07 UTC...AND THE EASTERN TERMINALS BETWEEN 08 AND 09 UTC. EXPECT THE ACTIVITY TO MOVE OUT OF THE REGION SHORTLY AFTER DAY BREAK. DURING THE DAY TODAY THE WINDS WILL BE A LITTLE GUSTY OUT OF THE WEST-NORTHWEST...AND THIS MAY BE ENOUGH TO PREVENT A LAKE BREEZE FROM PUSHING FAR ENOUGH INLAND TO IMPACT THE TERMINALS THIS AFTERNOON. THERE COULD BE A FEW ISOLATED SHOWERS AND PERHAPS A THUNDERSTORM ACROSS NORTHERN ILLINOIS AGAIN THIS AFTERNOON AS ANOTHER DISTURBANCE MOVES ACROSS THE AREA. HOWEVER...THIS THREAT IS TOO LOW TO INCLUDE IN THE TAF. KJB //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM-HIGH IN SHRA AT THE TERMINALS OVERNIGHT. * LOW-MEDIUM IN THUNDERSTORMS OVER THE TERMINALS OVERNIGHT. * VERY LOW THAT A LAKE BREEZE WILL IMPACT THE TERMINALS LATE THIS AFTERNOON. * LOW THAT ANY ISOLATED SHRA OR TS WILL AFFECT EITHER TERMINAL THIS AFTERNOON. KJB //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY AND THURSDAY...VFR FRIDAY THROUGH SUNDAY...GENERALLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE PERIOD. 2% && .MARINE... 152 PM CDT NO MAJOR CONCERNS THROUGH THE PERIOD FOR THE MARINE FORECAST...WITH FOCUS MAINLY ON A SERIES OF RELATIVELY WEAK COLD FRONTAL PASSAGES THROUGH TUESDAY BEFORE HIGH PRESSURE SPREADS ACROSS THE WESTERN LAKES LATER WEDNESDAY NIGHT AND THURSDAY. IN THE NEAR TERM...LOW PRESSURE WAS PASSING NORTH OF THE LAKES FROM NORTHEASTERN ONTARIO INTO QUEBEC EARLY THIS AFTERNOON WITH A COLD FRONT TRAILING SOUTHWEST INTO FAR NORTHWEST INDIANA JUST SOUTH OF THE LAKE MICHIGAN SHORE AT 18Z. WINDS HAD BECOME VARIABLE ON THE SOUTHERN PORTION OF THE LAKE IN THE BAGGY GRADIENT BEHIND THE COLD FRONT...ALLOWING WEAK LAKE BREEZE DEVELOPMENT AROUND THE SOUTH END OF THE LAKE. FARTHER NORTH...WINDS HAVE BACKED TO THE SOUTHWEST WITH THE GRADIENT TIGHTENING A BIT IN ADVANCE OF THE NEXT MID-LEVEL DISTURBANCE TRACKING ACROSS THE UPPER MIDWEST. THIS MID-LEVEL WAVE WILL MOVE ACROSS THE REGION LATER TONIGHT...ALLOWING ANOTHER WEAK COLD FRONT TO SAG ACROSS THE NORTHERN PART OF THE LAKE LATE TONIGHT. YET ANOTHER MORE AMPLIFIED DISTURBANCE WILL SPREAD OVER THE WESTERN LAKES TUESDAY...WITH A DEVELOPING WEAK AREA OF SURFACE LOW PRESSURE MOVING EAST OF THE LAKE BY THE AFTERNOON AND NORTHWEST WINDS DEVELOPING. SPEEDS LOOK TO REMAIN FAIRLY MODEST...GENERALLY IN THE 15-20 KT RANGE DURING HIGHEST PERIODS. A THIRD DISTURBANCE SWINGS ACROSS THE NORTHERN LAKES...WI/MI LATE TUESDAY NIGHT...RESULTING IN SOME BACKING OF THE WINDS ON NORTHERN LAKE MICHIGAN...BUT THESE TOO TURN NORTHWEST AGAIN BY WEDNESDAY AFTERNOON. HIGH PRESSURE THEN PRESSES EASTWARD INTO THE MISSISSIPPI RIVER VALLEY BY WEDNESDAY EVENING...AND ACROSS LAKE MICHIGAN WEDNESDAY NIGHT AND THURSDAY. WINDS WILL THEN BECOME SOUTH-SOUTHEAST THURSDAY NIGHT AS THE RIDGE MOVES OFF TO THE EAST. RATZER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
614 PM CDT Wed Jul 9 2014 ...Updated aviation section... .SHORT TERM...(This evening through Thursday) ISSUED AT 205 PM CDT WED JUL 9 2014 The main challenge in the forecast tonight and Thursday is precipitation chances, extent, and thunderstorm severity. Surface-based thunderstorms are expected to develop across northeast Colorado in vicinity of, or just downstream of Cheyenne Ridge. The former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a small MCS would develop and roll southeast toward far west-central Kansas. The latest 12Z runs of both the models, however, are less aggressive with this idea. That being said, the HRRR (using WRF-ARW core) late morning runs insist on northeast Colorado activity evolving southeast through the evening across northeastern Kansas and eventually into our far northwestern zones (Syracuse to Scott City). We will maintain some Chance POPs in the far west-central Kansas counties north of Hwy 50 and generally west of Hwy 283 through the evening. Another MCS will either roll south-southeast out of Nebraska and interact with the western MCS or remain a separate entity all together and redevelop around 04-06Z across north central/central Kansas along a strengthening zone of warm frontogenesis in the 850-750mb layer. We will have some 40 POPs from Hays to Pratt in the 05-12Z time frame, but these may need to be raised early this evening if short term trends favor a more western scenario for potential MCS. The overall severe weather threat looks fairly minimal, despite a SLGT risk being issued by SPC. Any large hail threat would be confined to areas of far west-central Kansas (but more likely across northeastern Colorado and northwestern Kansas) with strong straight-line winds to 65 mph the most likely threat with any bowing segments during the mid to late evening hours. After that, a very heavy rain threat will develop during the overnight hours across central Kansas. It remains to be seen, though, how far west the core of the nocturnal MCS will be. It seems most likely this will stay across portions of central and south central Kansas just east of our forecast area (east of a Hays to Pratt line). Going in to the day Thursday, a warmer day is forecast with warmer overall temperatures in the lower troposphere (to +29C at 850mb as far east as the Hwy 283 corridor). This should allow surface temperatures late afternoon reaching close to, if not 100F (especially along/west of Hwy 83 where evapotransporation will be less). A fairly strong gradient will yield a windier day with south-southwest winds 20 to 23 knots sustained in the afternoon. .LONG TERM...(Thursday night through Wednesday) ISSUED AT 246 PM CDT WED JUL 9 2014 Thursday night/Friday: Minimums overnight Thursday will be quite mild - 70s - as southerly winds continue through the overnight in association with continued surface lee troughing. Friday will be a hot day with max values at 97-100F. There will be a slight chance for tstms from Hugoton to Hays and points west, but convection may remain out of the area and limited to eastern Colorado and into southwest Nebraska. Another mild night with widespread 70s for lows is expected heading into Saturday morning. Saturday and beyond: A slightly better chance of coverage of storms is expected Saturday as a frontal boundary sinks farther to the south across Kansas. Ahead of the front, temperatures will be quite hot with values around 100F. A weak cool down is expected Sunday as the front heads south and slightly cooler 850-hPa temperatures advect across the region. Will have to watch out for convection across the western zones in this upslope flow pattern. The EC indicates another shot for an MCS Monday, as northwesterly flow aloft and low-level upslope flow continues across the High Plains. The best chance for precip area-wide is expected Tuesday as a rather cold air mass (for July standards) moves across the Plains. The EC has been very consistent with this cool down and associated precipitation. 850-hPa temperatures by the middle portion of next decrease as low as 8-10C! Very pleasant and highly abnormal Summer weather in regards to temperatures is possible in about a week from now with highs in the 70/80s and lows possibly in the 50s! The front could slow down, so exact timing is in question. Stuck with the allblend temperature solution for now. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) ISSUED AT 612 PM CDT WED JUL 9 2014 VFR conditions will prevail overnight with mostly clear skies. Winds will generally be from the south around 15 knots. There is a slight chance for thunderstorms across the HYS terminal around midnight but have left it out of the TAFs at this time. && .PRELIMINARY POINT TEMPS/POPS... DDC 67 97 72 98 / 10 10 0 10 GCK 66 98 71 99 / 20 10 0 20 EHA 68 98 71 97 / 20 0 0 20 LBL 68 99 71 99 / 10 0 0 10 HYS 66 95 72 99 / 40 10 10 20 P28 68 96 72 98 / 20 30 0 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Sugden AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
235 AM CDT Tue Jul 8 2014 ...UPDATE TO LONG TERM... .SHORT TERM...(This evening through Tuesday) ISSUED AT 227 PM CDT MON JUL 7 2014 Tonight: The main focus for tonight is where convection will be located and how severe. Right now, visible satellite imagery shows some developing cumulus across the Plains of east-central Colorado. Expect further development of cumulus into northwest Kansas through the afternoon. This activity is along a frontal boundary. Convective allowing models break out thunderstorms this evening with the best chances along the I-70 corridor. Storms may extend all the way down to Highway 96, though, later tonight. As far as severity, some of the models want to mix out current dewpoints, which, so far, is not happening as much as the models indicate. Running the thermodynamic and wind-related parameters through the Large Hail Parameter (LHP) comes up with a value of 6. This basically suggests that hail could potentially be up to the size of golf balls. Not really sure if we will get a sustained weakly rotating updraft or not, so hail could be smaller. There is not a threat of tornadoes. There could be 60+ mph outflow winds, as an inverted-v thermodynamic profile is expected. Have the highest pops for Trego and Ellis counties and then taper values quickly southward as thunderstorms are not expected along and south of a line from Coolidge to St. John. The most recent HRRR has storms south of this line, however, this model tends to overdo cold pools and resultant upscale growth. Overnight lows will be in the 60s/70s. Tomorrow: Much cooler temperatures are expected for tomorrow as the aforementioned front sinks south of the region. Have lowered maximums as the majority of the models are now cooler with "cold" air advection in the wake of the front. Expecting maximums mostly in the mid 80s along with 10-20 mph N/NE winds. There could be some storms along and south of the Arkansas river...have slight pops in after 21Z, but most of the precipitation will be during the long term period. .LONG TERM...(Wednesday through Monday) ISSUED AT 230 AM CDT TUE JUL 8 2014 Medium range models indicate a northwesterly flow aloft prevailing across the Western High Plains early in the period Wednesday as an upper level ridge axis slowly shifts eastward across the Intermountain West. A series of H5 vort maxima are projected to cycle off the ridge axis and drop southeastward across the high plains of eastern Colorado and western Kansas. Meanwhile, a prevailing southeasterly flow near the surface will continue to draw ample moisture up into central and western Kansas while a lee side trough of low pressure develops across eastern Colorado. As a result, thunderstorms are likely across eastern Colorado Wednesday afternoon as lower/mid level lapse rates steepen across the high plains. These storms will drift eastward, potentially moving into west central and southwest Kansas overnight. Additional thunderstorm development will be possible across central Kansas toward early Thursday morning as the surface trough axis pushes eastward across western Kansas overnight. This and surface high pressure parked across the Great Lakes Region will enhance an area of convergence across central and eastern Kansas, not to mention an axis of higher surface dewpoints being drawn northwest into central Kansas within the upslope flow. Although the flow aloft is expected to be less than favorable, enough forcing/lift near the surface will exist to support thunderstorm development across central Kansas early Thursday with any storms moving off to the east by the afternoon time frame. Drier conditions are expected Friday as the upper level ridge moves further east out of the Rockies into the Western High Plains. Near normal temperatures are likely Wednesday as a lee side trough of low pressure develops across eastern Colorado while surface high pressure drops southeast out of the Northern Plains into the southern Great Lakes Region. This will set up a south to southeasterly flow into western Kansas drawing slightly warmer air north into western Kansas. The GFS/ECMWF show H85 temperatures warming slightly from the day previous with values in the lower 20s(C) across central Kansas to near 30C in extreme southwest Kansas. With GFS/ECMWF model soundings showing steep low level lapse rates developing by Wednesday afternoon, look for highs well up into the mid to upper 80s(F) across central Kansas with lower to mid 90s(F) across much of southwest Kansas. Widespread 90s(F) are expected Thursday and Friday as the warming trend continues through the end of the week. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1209 AM CDT TUE JUL 8 2014 Conditions will continue to be VFR, with mid level cigs in the bkn100 range. There is just a slight chance for thunderstorms at the GCK and DDC TAF sites, but confidence is not high enough to include in TAFS. Winds will generally be from the northeast at 15g25kts tonight, and then becoming north at 7 to 8 knots around 18Z. && .PRELIMINARY POINT TEMPS/POPS... DDC 86 64 89 68 / 10 20 20 30 GCK 85 63 90 67 / 10 20 20 20 EHA 85 64 93 70 / 20 30 20 30 LBL 87 65 94 69 / 20 30 20 20 HYS 85 61 89 67 / 10 10 20 30 P28 89 67 90 69 / 20 20 20 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...JJohnson AVIATION...Burke
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1225 AM CDT Tue Jul 8 2014 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Tuesday) Issued at 259 PM CDT MON JUL 7 2014 Currently monitoring visible satellite this afternoon where multiple boundaries are positioned across the region. A weak boundary was tracking southeast through the CWA while a stronger area of outflow winds was pushing southward into southern NE and far northern KS. A weak warm front resided near the KS/NE border while the stronger cold front was located over southern SD. Remnant cloud cover from this morning`s showers were finally exiting east central KS, allowing temps to quickly rise into the 90s, as heat indices approach the low 100s. Dewpoints continue to mix down into the low and middle 60s. On the water vapor in the mid levels, two vorticity maxima were noted over northern NE and a stronger wave dropping southeast from North Dakota. Late this afternoon, surface CAPE near 3000 J/KG while effective shear increases between 30 and 50 kts is supportive of strong to severe convection. Main limiting factor for surface based convection is the capping inversion holding across much of the area as seen on the 19Z KTOP RAOB. Latest 4-KM WRF, HRRR, and RUC keep convection at bay until after 00Z but could not entirely rule out a few updrafts developing along the leading outflow boundary or warm front in vicinity of KS/NE border. If a storm develops, it will be capable of large hail and damaging winds. Highest chances for severe convection reside after 00Z as scattered storms along the reinforcing cold front and upper trough shift south and east across Nebraska, northeast Kansas, and northern Missouri. the progressive nature of the system, in addition to stout forward propagating Corfidi vectors approaching 55 to 60 kts signal damaging winds to be the primary hazards with this evening`s storms. Large hail is also possible. Locally heavy rainfall will depend on the speed of the line and any training convection that occurs towards central KS along the boundary. Tornado potential is low in far northern KS where the frontal boundary and weak low level shear maximizes near 15 kts. Likely precip chances were focused over northern, northeast, and east central areas based on the position of the upper trough axis as the main line of storms quickly shifts southeast overnight. Guidance is on track to clear precip through by Tuesday mid morning as skies become mostly sunny during the afternoon. A cooler and stable airmass in the system`s wake will only bring temps to the 80s for highs. Northerly winds increase between 10 and 15 mph sustained. .LONG TERM...(Tuesday Night through Monday) Issued at 259 PM CDT MON JUL 7 2014 Wed/Thurs...Should have a cool night Tuesday night as skies clear and cooler airmass with lower dewpoints slides southward into the forecast area. Strong sunshine and deeper mixing on Wednesday should return high temperatures back into the middle 80s east to upper 80s west. Still some consensus that front retreats back northeast overnight Wednesday night into Thursday and brings a chance for storms as it does so, although coverage may be shut down quickly as warm temps and cap return aloft by the late afternoon Thursday. Eastern counties may be able to stay a few degrees cooler depending on how fast clouds and precip chances diminish. As upper flow becomes slightly northwest into Thursday night, passing wave still progged to generate an MCS mainly north of our area then sliding east. Kept slight chances as some models slide this boundary into our forecast area. Some discrepancies in the extended as EC lays this boundary over the area through the weekend while GFS is farther north and a warmer drier solution. The GFS ensembles favor the warmer pattern and have left the extended as such. && .AVIATION...(For the 06Z TAFs through 06Z Tuesday Night) Issued at 1225 AM CDT TUE JUL 8 2014 TSRA still likely to affect the terminals through 09Z. Not expecting strong wind gusts with these storms. Winds will be variable then become north. VFR cigs expected with MVFR vsbys with the TSRA. Clouds scatter out after 12Z and north winds around 10 kts are expected after 14Z, then decrease after 02Z Wednesday. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Bowen LONG TERM...67 AVIATION...53
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1215 AM CDT Tue Jul 8 2014 ...Updated for the aviation discussion... .SHORT TERM...(This evening through Tuesday) ISSUED AT 227 PM CDT MON JUL 7 2014 Tonight: The main focus for tonight is where convection will be located and how severe. Right now, visible satellite imagery shows some developing cumulus across the Plains of east-central Colorado. Expect further development of cumulus into northwest Kansas through the afternoon. This activity is along a frontal boundary. Convective allowing models break out thunderstorms this evening with the best chances along the I-70 corridor. Storms may extend all the way down to Highway 96, though, later tonight. As far as severity, some of the models want to mix out current dewpoints, which, so far, is not happening as much as the models indicate. Running the thermodynamic and wind-related parameters through the Large Hail Parameter (LHP) comes up with a value of 6. This basically suggests that hail could potentially be up to the size of golf balls. Not really sure if we will get a sustained weakly rotating updraft or not, so hail could be smaller. There is not a threat of tornadoes. There could be 60+ mph outflow winds, as an inverted-v thermodynamic profile is expected. Have the highest pops for Trego and Ellis counties and then taper values quickly southward as thunderstorms are not expected along and south of a line from Coolidge to St. John. The most recent HRRR has storms south of this line, however, this model tends to overdo cold pools and resultant upscale growth. Overnight lows will be in the 60s/70s. Tomorrow: Much cooler temperatures are expected for tomorrow as the aforementioned front sinks south of the region. Have lowered maximums as the majority of the models are now cooler with "cold" air advection in the wake of the front. Expecting maximums mostly in the mid 80s along with 10-20 mph N/NE winds. There could be some storms along and south of the Arkansas river...have slight pops in after 21Z, but most of the precipitation will be during the long term period. .LONG TERM...(Tuesday night through Monday) ISSUED AT 308 PM CDT MON JUL 7 2014 The cold front which will come down Tuesday will slow its southward push and weaken Tuesday Night. The frontal zone, around 800mb will be across the northern Panhandles northeastward along the KS-OK border, which will be a focus for at least isolated or widely scattered thunderstorms. It is still unclear whether a small mesoscale convective system (MCS) will develop along the frontal zone or not (and if so, whether it will be this far north into southwest Kansas or not). For now, we will keep Chance POPs (25+) across far southwest Kansas from roughly Elkhart to Meade with Slight Chance (15-24) from roughly Scott City to Stafford. The front will dissolve by Wednesday, however temperatures will still be mild by early/mid July standards with highs in the upper 80s to lower 90s. Any thunderstorms Wednesday through early/mid evening should be confined to the higher terrain west of the southwest Kansas region. Warm frontogenesis will increase in the 06-12Z time frame early Thursday morning in the 850-700mb layer, and we will continue to carry Chance POPs across central and south-central Kansas. The updated forecast does reduce the POPs along/west of Highway 283, though. The summer ridge will build in the mid-upper troposphere with lower troposphere responding with quite a bit warmer temperatures in the +27 to +29C range at 850mb. Even slightly warmer temperatures Friday will support afternoon surface temperatures in the 99 to 101F territory. We will carry some Slight Chance POPs in the western/northwester zones for mainly diurnal lee trough/higher terrain storms which may drift into western Kansas. As we head into the upcoming weekend, we will start to see some amplification occurring in the jet stream pattern cross northwestern North America, with a pronounced ridge developing along the Pacific Coast of British Columbia. This would lead to downstream troughing throughout much of the rest of Canada into the Upper Midwest region of the CONUS. What this would mean for southwestern Kansas is the eventual frontal passage, perhaps as early as late Saturday (ECMWF) or Sunday (Canadian GEM). During the 14-17 July time frame, there is a large degree of uncertainty in how the upper tropospheric pattern will play out, but the ECMWF does suggest a much cooler and wetter scenario during this 8-10 Day time frame. To a lesser degree, the GFS does hint at this, but is also quite a bit delayed in longwave troughing across the northern CONUS. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1209 AM CDT TUE JUL 8 2014 Conditions will continue to be VFR, with mid level cigs in the bkn100 range. There is just a slight chance for thunderstorms at the GCK and DDC TAF sites, but confidence is not high enough to include in TAFS. Winds will generally be from the northeast at 15g25kts tonight, and then becoming north at 7 to 8 knots around 18Z. && .PRELIMINARY POINT TEMPS/POPS... DDC 64 88 68 97 / 20 20 20 20 GCK 63 89 67 98 / 20 20 20 10 EHA 64 91 70 98 / 30 20 20 10 LBL 65 92 69 99 / 30 20 20 10 HYS 63 88 67 95 / 10 10 30 30 P28 67 89 69 96 / 20 20 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Umscheid AVIATION...Burke
AREA FORECAST DISCUSSION
NWS JACKSON KY
454 PM EDT TUE JUL 8 2014 .MESOSCALE UPDATE... ISSUED AT 454 PM EDT TUE JUL 8 2014 STORMS CONTINUE TO HAVE A HARD TIME ORGANIZING. UPDRAFTS DO NOT APPEAR TO BE ABLE TO MUSTER ENOUGH STRENGTH TO OVERCOME SOME WARM AIR BETWEEN 400 AND 500 MB. MODEL SOUNDINGS DO NOT SHOW THIS WARM LAYER GOING AWAY. AN ISOLATED SEVERE THUNDERSTORM WITH GUSTY WINDS CANNOT BE RULED OUT INTO THE EVENING...BUT SEVERE THREAT APPEARS TO BE DWINDLING. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 258 PM EDT TUE JUL 8 2014 STORMS HAVE BEEN A LITTLE SLOW TO DEVELOP OVER EAST KENTUCKY DUE TO PERSISTENT CLOUD COVER...BUT BREAKS ARE DEVELOPING IN THE CLOUDS AND STORMS SHOULD RESPOND TO THIS AND THE APPROACHING COLD FRONT AND IGNITE OVER THE NEXT COUPLE OF HOURS. HRRR HAS BEEN ADAMANT THAT STORMS WILL BE SCATTERED AT BEST OVER OUR AREA...BUT LATEST RAP MAKES A LITTLE MORE SENSE CONSIDERING THE ENVIRONMENT. IT DEVELOPS CONVECTION OVERHEAD AND THEN TO OUR NORTHWEST AND WEST WITH THE FRONT. THIS CONVECTION THEN MOVES OVER US INTO THE EVENING...WITH THE UPPER CUMBERLAND REGION LOOKING TO TAKE THE BRUNT OF THE ACTIVITY. FORECAST WAS TRENDED IN THIS DIRECTION AND DID LOWER POPS A BIT...ESPECIALLY IN THE NORTH BASED ON MODEL DATA. WILL CONTINUE TO ADVERTISE THE SEVERE THREAT THROUGH THE EVENING. THE FRONT WILL HANG UP OVER SOUTHEAST KENTUCKY ON WEDNESDAY. CLOUD COVER MAY BE SLOW TO ERODE AGAIN...BUT MODELS INDICATE STEEPENING LAPSE RATES DEVELOPING DURING THE DAY WITH ADEQUATE CAPE TO POP OFF AN ISOLATED SHOWER OR STORM JUST ABOUT ANYWHERE AS TEMPS RISE AGAIN INTO THE 80S. THIS THREAT WILL END QUICKLY EARLY IN THE EVENING WITH THE LOSS OF DAYTIME HEATING AND EXPECT DECREASING CLOUDS WEDNESDAY NIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 300 PM EDT TUE JUL 8 2014 THE MODELS WERE IN PRETTY GOOD AGREEMENT IN THE EXTENDED THIS TIME AROUND. THE 12Z RUN OF THE ECMWF WAS COMING MUCH MORE INTO LINE WITH THE GFS MODEL...WITH A DRY START TO THE PERIOD AS HIGH PRESSURE GRADUALLY DRIFTS OFF TO THE SOUTHEAST TOWARD THE END OF THE WEEK. THE CONSENSUS VIEW IS NOW FOR A VIGOROUS AREA OF UPPER LEVEL LOW PRESSURE TO MOVE ACROSS THE UPPER GREAT LAKES SOUTHERN CANADA AREA...PARTICULARLY OVER THE UPCOMING WEEKEND. THE TROUGH LOOKS TO BE AT ITS MOST POTENT FROM SUNDAY ONWARD...AS IT DIPS SOUTH OUT OF CANADA AND INTO THE NORTH CENTRAL CONUS TO BEGIN THE WORK WEEK NEXT WEEK. THE BULK OF THE EXTENDED LOOKS TO BE DRY AT THIS POINT...WITH THE ANTICIPATED PATTERN LENDING ITSELF TO MORE MOIST AND ACTIVE PERIOD AND RAIN CHANCES FROM SUNDAY ONWARD. TEMPERATURES THROUGHOUT THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW NORMAL...WITH THE COOLER DAY TIME HIGHS OCCURRING SUNDAY AND MONDAY AS CLOUD COVER AND PRECIPITATION BEGIN OVERSPREADING THE AREA. THE START OF THE PERIOD LOOKS TO BE MORE WARM AND HUMID. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 145 PM EDT TUE JUL 8 2014 THUNDERSTORMS ARE THE MAIN CONCERN THROUGH THE EVENING AND CONFIDENCE IS LOW ON THE EXACT TIMING AND IMPACTS AT ANY GIVEN LOCATION. GUSTY WINDS WILL ALSO BE A HINDRANCE BUT ARE EXPECTED TO DIE DOWN BY SUNSET. EXPECT STORMS TO DEVELOP OVER EASTERN KENTUCKY THROUGH MID AFTERNOON AND MOVE EASTWARD. TEMPO IFR CONDITIONS WITH GUSTY WINDS ARE LIKELY WHERE STORMS HIT. ADDITIONAL STORMS WILL LIKELY DEVELOP TO OUR WEST AND CONTINUE TO IMPACT AREA TERMINALS...PARTICULARLY FROM JKL SOUTH...INTO THE EVENING HOURS. THIS THREAT WILL DIMINISH FROM NORTH TO SOUTH OVERNIGHT. MODELS INDICATE A POTENTIAL FOR A PERIOD OF LOW CEILINGS TO DEVELOP LATE TONIGHT AND LAST INTO WEDNESDAY MORNING. WILL ADVERTISE AN MVFR CEILING OCCURRING AT TAF SITES AFTER 08Z AND LASTING UNTIL APPROXIMATELY 15Z...WITH VFR CONDITIONS ANTICIPATE THEREAFTER. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE...ABE SHORT TERM...ABE LONG TERM...AR AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
300 PM EDT TUE JUL 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 258 PM EDT TUE JUL 8 2014 STORMS HAVE BEEN A LITTLE SLOW TO DEVELOP OVER EAST KENTUCKY DUE TO PERSISTENT CLOUD COVER...BUT BREAKS ARE DEVELOPING IN THE CLOUDS AND STORMS SHOULD RESPOND TO THIS AND THE APPROACHING COLD FRONT AND IGNITE OVER THE NEXT COUPLE OF HOURS. HRRR HAS BEEN ADAMANT THAT STORMS WILL BE SCATTERED AT BEST OVER OUR AREA...BUT LATEST RAP MAKES A LITTLE MORE SENSE CONSIDERING THE ENVIRONMENT. IT DEVELOPS CONVECTION OVERHEAD AND THEN TO OUR NORTHWEST AND WEST WITH THE FRONT. THIS CONVECTION THEN MOVES OVER US INTO THE EVENING...WITH THE UPPER CUMBERLAND REGION LOOKING TO TAKE THE BRUNT OF THE ACTIVITY. FORECAST WAS TRENDED IN THIS DIRECTION AND DID LOWER POPS A BIT...ESPECIALLY IN THE NORTH BASED ON MODEL DATA. WILL CONTINUE TO ADVERTISE THE SEVERE THREAT THROUGH THE EVENING. THE FRONT WILL HANG UP OVER SOUTHEAST KENTUCKY ON WEDNESDAY. CLOUD COVER MAY BE SLOW TO ERODE AGAIN...BUT MODELS INDICATE STEEPENING LAPSE RATES DEVELOPING DURING THE DAY WITH ADEQUATE CAPE TO POP OFF AN ISOLATED SHOWER OR STORM JUST ABOUT ANYWHERE AS TEMPS RISE AGAIN INTO THE 80S. THIS THREAT WILL END QUICKLY EARLY IN THE EVENING WITH THE LOSS OF DAYTIME HEATING AND EXPECT DECREASING CLOUDS WEDNESDAY NIGHT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 300 PM EDT TUE JUL 8 2014 THE MODELS WERE IN PRETTY GOOD AGREEMENT IN THE EXTENDED THIS TIME AROUND. THE 12Z RUN OF THE ECMWF WAS COMING MUCH MORE INTO LINE WITH THE GFS MODEL...WITH A DRY START TO THE PERIOD AS HIGH PRESSURE GRADUALLY DRIFTS OFF TO THE SOUTHEAST TOWARD THE END OF THE WEEK. THE CONSENSUS VIEW IS NOW FOR A VIGOROUS AREA OF UPPER LEVEL LOW PRESSURE TO MOVE ACROSS THE UPPER GREAT LAKES SOUTHERN CANADA AREA...PARTICULARLY OVER THE UPCOMING WEEKEND. THE TROUGH LOOKS TO BE AT ITS MOST POTENT FROM SUNDAY ONWARD...AS IT DIPS SOUTH OUT OF CANADA AND INTO THE NORTH CENTRAL CONUS TO BEGIN THE WORK WEEK NEXT WEEK. THE BULK OF THE EXTENDED LOOKS TO BE DRY AT THIS POINT...WITH THE ANTICIPATED PATTERN LENDING ITSELF TO MORE MOIST AND ACTIVE PERIOD AND RAIN CHANCES FROM SUNDAY ONWARD. TEMPERATURES THROUGHOUT THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW NORMAL...WITH THE COOLER DAY TIME HIGHS OCCURRING SUNDAY AND MONDAY AS CLOUD COVER AND PRECIPITATION BEGIN OVERSPREADING THE AREA. THE START OF THE PERIOD LOOKS TO BE MORE WARM AND HUMID. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 145 PM EDT TUE JUL 8 2014 THUNDERSTORMS ARE THE MAIN CONCERN THROUGH THE EVENING AND CONFIDENCE IS LOW ON THE EXACT TIMING AND IMPACTS AT ANY GIVEN LOCATION. GUSTY WINDS WILL ALSO BE A HINDRANCE BUT ARE EXPECTED TO DIE DOWN BY SUNSET. EXPECT STORMS TO DEVELOP OVER EASTERN KENTUCKY THROUGH MID AFTERNOON AND MOVE EASTWARD. TEMPO IFR CONDITIONS WITH GUSTY WINDS ARE LIKELY WHERE STORMS HIT. ADDITIONAL STORMS WILL LIKELY DEVELOP TO OUR WEST AND CONTINUE TO IMPACT AREA TERMINALS...PARTICULARLY FROM JKL SOUTH...INTO THE EVENING HOURS. THIS THREAT WILL DIMINISH FROM NORTH TO SOUTH OVERNIGHT. MODELS INDICATE A POTENTIAL FOR A PERIOD OF LOW CEILINGS TO DEVELOP LATE TONIGHT AND LAST INTO WEDNESDAY MORNING. WILL ADVERTISE AN MVFR CEILING OCCURRING AT TAF SITES AFTER 08Z AND LASTING UNTIL APPROXIMATELY 15Z...WITH VFR CONDITIONS ANTICIPATE THEREAFTER. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ABE LONG TERM...AR AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
258 PM EDT TUE JUL 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 258 PM EDT TUE JUL 8 2014 STORMS HAVE BEEN A LITTLE SLOW TO DEVELOP OVER EAST KENTUCKY DUE TO PERSISTENT CLOUD COVER...BUT BREAKS ARE DEVELOPING IN THE CLOUDS AND STORMS SHOULD RESPOND TO THIS AND THE APPROACHING COLD FRONT AND IGNITE OVER THE NEXT COUPLE OF HOURS. HRRR HAS BEEN ADAMANT THAT STORMS WILL BE SCATTERED AT BEST OVER OUR AREA...BUT LATEST RAP MAKES A LITTLE MORE SENSE CONSIDERING THE ENVIRONMENT. IT DEVELOPS CONVECTION OVERHEAD AND THEN TO OUR NORTHWEST AND WEST WITH THE FRONT. THIS CONVECTION THEN MOVES OVER US INTO THE EVENING...WITH THE UPPER CUMBERLAND REGION LOOKING TO TAKE THE BRUNT OF THE ACTIVITY. FORECAST WAS TRENDED IN THIS DIRECTION AND DID LOWER POPS A BIT...ESPECIALLY IN THE NORTH BASED ON MODEL DATA. WILL CONTINUE TO ADVERTISE THE SEVERE THREAT THROUGH THE EVENING. THE FRONT WILL HANG UP OVER SOUTHEAST KENTUCKY ON WEDNESDAY. CLOUD COVER MAY BE SLOW TO ERODE AGAIN...BUT MODELS INDICATE STEEPENING LAPSE RATES DEVELOPING DURING THE DAY WITH ADEQUATE CAPE TO POP OFF AN ISOLATED SHOWER OR STORM JUST ABOUT ANYWHERE AS TEMPS RISE AGAIN INTO THE 80S. THIS THREAT WILL END QUICKLY EARLY IN THE EVENING WITH THE LOSS OF DAYTIME HEATING AND EXPECT DECREASING CLOUDS WEDNESDAY NIGHT. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 400 AM EDT TUE JUL 8 2014 THE MODELS START OUT IN VERY GOOD AGREEMENT WITH AN UPPER TROUGH AXIS JUST TO THE EAST OF THE AREA AND SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE NORTHWEST. THE COLD FRONT WILL BE WELL SOUTH AND EAST OF THE AREA. ON THURSDAY...A SHORT WAVE WILL MOVE ACROSS THE AREA AND MAY KICK UP SOME SHOWERS SOUTH OF THE HAL ROGERS PARKWAY. THE LATEST ECMWF KEPT THINGS DRY...SO THIS MAY BE TAKEN OUT OF THE FORECAST BY DAY SHIFT. FRIDAY SHOULD STAY DRY AND THEN ON SATURDAY...A COLD FRONT WILL BE MOVING INTO THE AREA FROM THE NORTHWEST. EASTERN KENTUCKY WILL BE IN WARM SECTOR OUT AHEAD OF THE FRONT AND THIS WILL BE THE START OF AN UNSETTLED PERIOD THAT WILL CONTINUE THROUGH MONDAY WHEN THE FRONT WILL FINALLY MOVE SOUTH AND EAST OF THE AREA. THE MODELS STAY IN GOOD GENERAL AGREEMENT THROUGH THE END OF THE PERIOD...HOWEVER THERE ARE ENOUGH NUANCES THAT THE CONFIDENCE IN THE TIMING OF THE WEEKEND AND BEYOND STARTS TO TAPER OFF. USED THE MODEL BLEND FOR THE TEMPERATURES AND THEN MADE SOME CORRECTIONS BASED ON ELEVATION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 145 PM EDT TUE JUL 8 2014 THUNDERSTORMS ARE THE MAIN CONCERN THROUGH THE EVENING AND CONFIDENCE IS LOW ON THE EXACT TIMING AND IMPACTS AT ANY GIVEN LOCATION. GUSTY WINDS WILL ALSO BE A HINDRANCE BUT ARE EXPECTED TO DIE DOWN BY SUNSET. EXPECT STORMS TO DEVELOP OVER EASTERN KENTUCKY THROUGH MID AFTERNOON AND MOVE EASTWARD. TEMPO IFR CONDITIONS WITH GUSTY WINDS ARE LIKELY WHERE STORMS HIT. ADDITIONAL STORMS WILL LIKELY DEVELOP TO OUR WEST AND CONTINUE TO IMPACT AREA TERMINALS...PARTICULARLY FROM JKL SOUTH...INTO THE EVENING HOURS. THIS THREAT WILL DIMINISH FROM NORTH TO SOUTH OVERNIGHT. MODELS INDICATE A POTENTIAL FOR A PERIOD OF LOW CIELINGS TO DEVELOP LATE TONIGHT AND LAST INTO WEDNESDAY MORNING. WILL ADVERTISE AN MVFR CEILING OCCURRING AT TAF SITES AFTER 08Z AND LASTING UNTIL APPROXIMATELY 15Z...WITH VFR CONDITIONS ANTICIPATE THEREAFTER. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ABE LONG TERM...JJ AVIATION...ABE
AREA FORECAST DISCUSSION
NWS PADUCAH KY
658 AM CDT Tue Jul 8 2014 .UPDATE... Issued at 658 AM CDT TUE JUL 8 2014 The AVIATION section has been updated for the 12Z TAF issuance. && .SHORT TERM...(Today through Thursday) Issued at 258 AM CDT TUE JUL 8 2014 The bulk of the short term period will be dependent on the evolution of the MCS just about to enter southwest Illinois and southeast Missouri. The leading line convection has diminished significantly, as have the winds behind the line. Have not seen any severe wind reports for quite awhile upstream, and really would not expect the system to increase. The RAP indicates that the 0-3km shear is very weak and parallel to the leading line. There appears to be a comma head/MCV feature moving east across central Illinois, and that should continue to push away from our area. Meanwhile, Corfidi Vectors over Missouri indicate a southward propagation. Therefore, we may be in for some sort of split for our area. There is decent surface air, theta-e values in the 345-349 range, throughout southern Illinois and southeast Missouri, so would expect convection to continue to bounce around on the outflow boundary as it moves southeast through southern Illinois and southeast Missouri through daybreak. With disorganized leading convection, figure the stratiform area will also begin to diminish, so there will likely be a significant weakening trend in the coverage of precipitation over the area in the 12z-15Z timeframe. The big question then is where will storms be able to fire up this afternoon and evening? The cold front is located from southeast Iowa to north central Kansas as of 730Z, and it does not have a tremendous push with it. The consensus of 00Z guidance brings into the northwest part of the region this afternoon, and surface dewpoints in the lower 70s are expected ahead of the front. Therefore, much of the area may be under the gun for more convection along and ahead of the cold front this afternoon and evening. The hi-res guidance really seems to be focusing on the southern third of the area for development. Perhaps the MCS will thoroughly stabilize the airmass across the northern half of the area. I really don`t have a good feel for this one. Decided to go with a band of low-end likely PoPs in the north around 18Z, and then push it slowly southeast through the afternoon and into the evening. Feel that it will be out of the area by 06Z tonight, but left a chancy PoP in the southeast overnight just to be safe. Enough dry air should arrive to keep the area dry for Wednesday, despite decent cyclonic flow aloft. A few severe storms will be possible this afternoon, if we can destabilize enough. The wind fields should be strong enough to support a few severe storms with damaging winds the main concern. Temperatures today are a crap shoot with the convection and convective debris expected. Therefore, went close to consensus guidance. Went on the warm side of guidance for tonight with only weak cool, dry advection expected. Consensus should be close again Wednesday with the dry air advecting/mixing across the region. Trended a bit cooler for Wednesday night and warmer Thursday, both due to the dry airmass expected. .LONG TERM...(Thursday Night through Monday) Issued at 258 AM CDT TUE JUL 8 2014 High pressure will continue to bring dry weather Thursday night before moving off to the east on Friday. Temperatures and dewpoints will climb a couple of degrees per day through the weekend on warm and moist low level winds. Thursday night lows in the middle 60s will give way to lows over the weekend in the lower 70s. Highs will nudge up from the upper 80s on Friday into the lower 90s for the weekend. Aloft, the region will stay in northwesterly flow on the fringe of an upper level low. While an isolated chance of a shower or storm will be possible on Saturday, the better chance will come Sunday as an upper level disturbance moves north of the region. Chance pops in the northeastern part of the forecast area will lower to slight pops over the Ozark foothills. Models are highly variable with the weather early next week. The GFS aggressively pushes a front through the Ohio Valley on Monday and stalls it over the Tennessee Valley before lifting back north late Tuesday hinting at a very wet period for our region. The ECMWF on the other hand is much weaker with the front on Monday but does also stall it to our south. It, however, keeps it to our south through the better part of the week with energy producing rain chances up around the Great Lakes and to our south along the stalled boundary. At any rate, have high chance pops on Monday with the passage of a frontal boundary. Temperatures will be tempered somewhat on Monday with cloud cover and precipitation with highs back down into the upper 80s. && .AVIATION... Issued at 658 AM CDT TUE JUL 8 2014 Area VAD wind profiles indicate that there is 30kts of west or west northwest winds available to mix down this morning. The latest guidance advertises sustained winds into the teens, and some gusts to 20kts or a bit more through the morning. As a cold front moves through the area, at least scattered thunderstorms are expected to develop and move east southeast across the entire region this afternoon. VCTS seems to be the most reasonable approach at this time, since confidence in the coverage and timing is low. Winds will become northwest by this evening, but they will be light for much of the night. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ UPDATE...DRS SHORT TERM...DRS LONG TERM...ML AVIATION...DRS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
259 AM CDT Tue Jul 8 2014 .SHORT TERM...(Today through Thursday) Issued at 258 AM CDT TUE JUL 8 2014 The bulk of the short term period will be dependent on the evolution of the MCS just about to enter southwest Illinois and southeast Missouri. The leading line convection has diminished significantly, as have the winds behind the line. Have not seen any severe wind reports for quite awhile upstream, and really would not expect the system to increase. The RAP indicates that the 0-3km shear is very weak and parallel to the leading line. There appears to be a comma head/MCV feature moving east across central Illinois, and that should continue to push away from our area. Meanwhile, Corfidi Vectors over Missouri indicate a southward propagation. Therefore, we may be in for some sort of split for our area. There is decent surface air, theta-e values in the 345-349 range, throughout southern Illinois and southeast Missouri, so would expect convection to continue to bounce around on the outflow boundary as it moves southeast through southern Illinois and southeast Missouri through daybreak. With disorganized leading convection, figure the stratiform area will also begin to diminish, so there will likely be a significant weakening trend in the coverage of precipitation over the area in the 12z-15Z timeframe. The big question then is where will storms be able to fire up this afternoon and evening? The cold front is located from southeast Iowa to north central Kansas as of 730Z, and it does not have a tremendous push with it. The consensus of 00Z guidance brings into the northwest part of the region this afternoon, and surface dewpoints in the lower 70s are expected ahead of the front. Therefore, much of the area may be under the gun for more convection along and ahead of the cold front this afternoon and evening. The hi-res guidance really seems to be focusing on the southern third of the area for development. Perhaps the MCS will thoroughly stabilize the airmass across the northern half of the area. I really don`t have a good feel for this one. Decided to go with a band of low-end likely PoPs in the north around 18Z, and then push it slowly southeast through the afternoon and into the evening. Feel that it will be out of the area by 06Z tonight, but left a chancy PoP in the southeast overnight just to be safe. Enough dry air should arrive to keep the area dry for Wednesday, despite decent cyclonic flow aloft. A few severe storms will be possible this afternoon, if we can destabilize enough. The wind fields should be strong enough to support a few severe storms with damaging winds the main concern. Temperatures today are a crap shoot with the convection and convective debris expected. Therefore, went close to consensus guidance. Went on the warm side of guidance for tonight with only weak cool, dry advection expected. Consensus should be close again Wednesday with the dry air advecting/mixing across the region. Trended a bit cooler for Wednesday night and warmer Thursday, both due to the dry airmass expected. .LONG TERM...(Thursday Night through Monday) Issued at 258 AM CDT TUE JUL 8 2014 High pressure will continue to bring dry weather Thursday night before moving off to the east on Friday. Temperatures and dewpoints will climb a couple of degrees per day through the weekend on warm and moist low level winds. Thursday night lows in the middle 60s will give way to lows over the weekend in the lower 70s. Highs will nudge up from the upper 80s on Friday into the lower 90s for the weekend. Aloft, the region will stay in northwesterly flow on the fringe of an upper level low. While an isolated chance of a shower or storm will be possible on Saturday, the better chance will come Sunday as an upper level disturbance moves north of the region. Chance pops in the northeastern part of the forecast area will lower to slight pops over the Ozark foothills. Models are highly variable with the weather early next week. The GFS aggressively pushes a front through the Ohio Valley on Monday and stalls it over the Tennessee Valley before lifting back north late Tuesday hinting at a very wet period for our region. The ECMWF on the other hand is much weaker with the front on Monday but does also stall it to our south. It, however, keeps it to our south through the better part of the week with energy producing rain chances up around the Great Lakes and to our south along the stalled boundary. At any rate, have high chance pops on Monday with the passage of a frontal boundary. Temperatures will be tempered somewhat on Monday with cloud cover and precipitation with highs back down into the upper 80s. && .AVIATION... Issued at 1159 PM CDT MON JUL 7 2014 Thunderstorm complex barreling across Missouri will likely impact the region late tonight. Given the trajectory into a better feed of instability, current thinking is that KCGI and KPAH both stand the better chance of impact later tonight versus KEVV and KOWB. While the overnight activity weakens and diminishes through the morning, more outflow focused development is expected to regenerate with peak heating as a cold front drops south across the area. This should largely be south of the area by 00Z Wednesday. VFR conditions will prevail outside of thunderstorm activity. South winds 5 to 10 knots tonight will become southwest at 10 to 15 knots with gusts to 20 knots on Tuesday. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...DRS LONG TERM...ML AVIATION...RJP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
114 AM EDT Tue Jul 8 2014 ...Updated Aviation Discussion... ...Forecast Update... Issued at 1100 PM EDT Mom Jul 7 2014 The HRRR short range model has initialized the current convection across the area quite well. For the rest of this evening and the early morning hours expect mostly dry conditions once light rain across south central Kentucky dissipates by midnight. No new convection is expected until a fast moving storm complex now over northern Missouri moves into west central Kentucky and southern Indiana during the pre-dawn hours. Precipitation chances will, therefore ramp up again around dawn, especially for locations south of Interstate 64 and west of I - 65 .SHORT TERM (Now through Tuesday)... Issued at 308 PM EDT Mon Jul 7 2014 This afternoon a cold front extended from the Great Lakes through Illinois and Missouri to the Great Plains. Storms have fired ahead of this front, especially between Indianapolis and St Louis in an area of maximized deep moisture convergence and CAPE. These storms will slide to the ESE and will provide southern Indiana and northern sections of central Kentucky with scattered storms this evening. By the time the storms reach here they will likely begin to weaken, so any severe weather that might occur will be isolated. Locally heavy downpours and gusty winds will be the main threats. Tonight an MCS will advance from Kansas/Nebraska this evening into IL/IN/OH early Tuesday morning. The LMK CWA will be on the southern edge of this feature, with showers and a few thunderstorms possible in southern Indiana and northern Kentucky as we`re waking up Tuesday morning. Those showers/storms are not expected to be severe. By Tuesday afternoon a line of storms is expected to erupt in the vicinity of the Ohio River. The synoptic cold front, an outflow boundary from the morning MCS, and differential heating will all be possible triggers to get the storms going. We`ll also have an upper trof entering the picture from the northwest. Though instability is always in question when we have morning clouds and showers, we should become unstable enough by afternoon such that severe weather will be a threat. Soundings are increasingly showing dry air aloft and bowing echoes are possible, so strong gusty winds will be the main threat. Precipitable water amounts around 2 inches will lead to locally torrential downpours. Tuesday evening the line of strong/severe storms will proceed through central and southern Kentucky. The strongest storms will weakening and move out of the area overnight. Tonight will be muggy, though southwest breezes will keep up around 10 mph through the night to help it feel a little better outside. Lows will be around 70. High temperatures Tuesday will be highly dependent on cloud cover...will go with middle and upper 80s. Tuesday night we`ll see rain-cooled lows in the middle and upper 60s. .LONG TERM (Tuesday Night through Sunday)... Issued at 245 PM EDT Mon Jul 7 2014 The synoptic pattern at the start of the long term period will feature rather amplified flow for mid July, with an amplified ridge across the western CONUS and an eastern trough centered over the Great Lakes region. This pattern will slowly de-amplify through the long term period, allowing the heat and humidity to return this upcoming weekend after a brief reprieve this week. Wednesday will begin with a cold front pushing southeast of the region. The overall trend in numerical guidance with this front has continued to be quicker, thus think most will remain dry Wednesday as cooler/drier air filters into the region. The only exception may be across southern KY where their proximity to the front may allow for a few lingering showers/storms, mostly during the first part of the day. It will feel quite pleasant, as highs will only top out in the low to mid 80s with reduced humidity values. The pleasant conditions will continue Thursday into Friday as another 1020+ mb surface ridge settles over the region. This ridge will allow for highs in the low to mid 80s Thursday, pushing into the mid and upper 80s Friday. However, both days will still be seasonably pleasant as dewpoints will only be in the upper 50s to lower 60s. The forecast becomes a bit more murky this weekend, as guidance begins to diverge. The GFS is the most aggressive with building an upper-level ridge into the region, which would limit convective activity due to capping aloft. However, the GEM/Euro/GFS Ensemble are in better agreement that this ridge will remain more to the southwest, placing the region in the better northwesterly flow aloft making for a more active period. Will lean towards the more active solution, which brings chances for showers/storms beginning Friday night and lasting at least through the end of the long term period. Temperatures this weekend will be tough given the convective potential, but it will be muggier with highs in the upper 80s to lower 90s. && .AVIATION (06Z TAF Update)... Issued at 100 AM EDT Tue Jul 8 2014 Earlier convection has ended across the area. VFR ceilings and southwest winds of around 5 to 10 mph are expected overnight through the early morning period at all TAF sites. A strong line of thunderstorms now over Missouri and Illinois will weaken some as it approaches southwestern Indiana and western Kentucky during the pre-dawn hours. However, it is expected to still bring a round of thunderstorms to SDF and BWG and probably LEX. This line will bring one or two hours of potentially gust winds, occasionally heavy rain and MVFR ceilings and visibilities. VFR conditions are expected until these storms arrive, which will be around 11z for SDF and BWG. If these storms hold together, they will affect LEX around 12 to 13z. After this first round of morning storms, additional thunderstorms development is likely at some point across central and southern Kentucky during the late morning and afternoon hours. Attempting to time development and movement at this point will be fruitless. Will therefore, add VCTS to TAFs for a somewhat extended time for BWG during the late morning and afternoon hours. West southwest winds will pick up by late morning and reach 12 to 15 mph with some gusts up to 25 mph by early afternoon. West winds will diminish to less than 10kt by 00z Wednesday. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........JSD Short Term.....13 Long Term......KJD Aviation.......JSD
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
331 PM CDT TUE JUL 8 2014 .DISCUSSION... AN UPPER LEVEL TROUGH IS IN THE PROCESS OF DIGGING SOUTHWARD ACROSS THE GREAT LAKES AND OHIO RIVER VALLEY TODAY AND WILL CONTINUE TO PROTRUDE FURTHER SOUTH AS IT PROGRESSES EAST. AT THE SAME TIME... MOISTURE HAS BEEN BACK ON THE INCREASE IN THE MID AND UPPER LEVELS. THIS MORNING/S AT LIX SHOWED A PRECIP WATER VALUE OF NEAR 1.5 INCHES AND MODEL SOUNDINGS INDICATE THAT THIS VALUE COULD BE NEAR 2 INCHES BY THE 00Z FLIGHT. SO ITS NO SURPRISE THAT QUITE A BIT OF CONVECTION HAS DEVELOPED TODAY. THE HRRR HAS DONE A PRETTY DECENT JOB OF INITIALIZING AND KEEPING UP WITH THE CURRENT RADAR TRENDS. ITS DEPICTION OF DIMINISHING ACTIVITY BY SUNSET AGREES WELL WITH TYPICAL EXPECTATIONS OF STORM DISSIPATION WITH LOSS OF DAYTIME HEATING. A WEAK COLD FRONT ASSOCIATED WITH THIS UPPER LEVEL TROUGH WILL GRADUALLY SAG CLOSER AND CLOSER TO THE AREA AS WE APPROACH THE WEEKEND. IT APPEARS THAT THE BOUNDARY WILL EVENTUALLY REACH THE CWA BUT WILL BE IN A NEARLY INDISCERNIBLE STATE. LOCAL WEATHER CONDITIONS FROM TODAY THROUGH THE WEEKEND WILL NOT BE VERY DIFFERENT FROM DAY TO DAY. DAYTIME POPS SHOULD GENERALLY BE AROUND 30-50 PERCENT WITH A PEAK OF 60 PERCENT ON THURSDAY. NOCTURNAL OFFSHORE SHOWERS POSSIBLE AS WELL. TEMPERATURES THROUGH THIS PERIOD WILL BE NEAR NORMAL. MEFFER && .AVIATION... MOISTURE RETURN HAS TRIGGERED SCATTERED CONVECTION THAT CONTINUES TO DEVELOP THIS AFTERNOON. WHILE MOST TERMINALS ARE VFR...CONVECTION WILL PRODUCE BRIEF IFR CONDITIONS AS THEY AFFECT TERMINALS. CARRYING VCTS WITH TEMPO IFR AS APPROPRIATE OVER THE NEXT 3-4 HOURS. CONVECTION SHOULD DIMINISH AS WE APPROACH SUNSET. VFR CONDITIONS WILL BE THE RULE OVERNIGHT...WITH CONVECTIVE DEVELOPMENT AGAIN ANTICIPATED ON WEDNESDAY BY LATE MORNING TO EARLY AFTERNOON. 35 && .MARINE... A BRIEF NOCTURNAL MAX OF 10 TO 15 KNOTS IN THE NEARSHORE WATERS OF LA AND MS ARE EXPECTED TONIGHT AND TOMORROW NIGHT AS A WEAK SURFACE TROUGH TO THE NORTH TIGHTENS THE PRESSURE GRADIENT. OTHERWISE... RELATIVELY LIGHT WIND AND WAVE CONDITIONS ARE EXPECTED TO PREVAIL THROUGH MOST OF THE UPCOMING WEEK DUE TO A RIDGE OF HIGH PRESSURE OVER THE REGION. SCATTERED CONVECTION WILL CONTINUE TO BE A THREAT THROUGH THE FORECAST PERIOD. 35 && .DECISION SUPPORT... DSS CODE...GREEN. DEPLOYED...NONE. ACTIVATION...NONE. ACTIVITIES...NONE. DECISION SUPPORT SERVICES (DSS) CODE LEGEND GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH VISIBILITY EVENT YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE. && .PRELIMINARY POINT TEMPS/POPS... MCB 71 92 71 92 / 20 40 20 60 BTR 73 92 73 92 / 30 40 10 50 ASD 73 92 74 92 / 20 40 20 60 MSY 76 92 76 91 / 30 40 10 50 GPT 76 91 77 91 / 20 40 20 50 PQL 72 91 73 91 / 20 40 30 50 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...NONE. MS...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1204 AM EDT TUE JUL 8 2014 .SYNOPSIS... UNSETTLED CONDITIONS WILL PERSIST ACROSS THE REGION THROUGH THURSDAY. && .NEAR TERM /THROUGH TUESDAY/... MDNGT UPDATE: WE XTNDED THE RISK OF ISOLD TSTMS A LITTLE LATER INTO THE ERLY MORN WED BASED ON PROJECTED FCST SOUNDINGS OF ELEVATED CAPE MOVG EWRD FROM QB PROV BETWEEN 12-30KFT ABV GROUND LVL TIL ABOUT 12-14Z...AT WHICH POINT...THESE ELEVATED CAPES MOVE INTO NB PROV. THIS APPEARS TO BACKED BY THE HRRR MODEL WHICH SHOWS ANOTHER ROUND OF ISOLD TO SCT SHWRS/ISOLD TSTMS VERY LATE TNGT INTO ERLY WED MORN ACROSS THE N. THIS TYPE OF SOUNDING SUPPORTS ACCAS TYPE OF CLDNSS IN SUPPORT OF THIS SHWR ACTIVITY. OTHERWISE...FCST HRLY TEMPS AND OVRNGT LOWS TNGT WERE MODIFIED SLIGHTLY BASED ON TRENDS FROM 11 PM OBS. PREV DISCUSSION: A DISTURBANCE WILL CROSS THE REGION EARLY TONIGHT WITH SHOWERS. SHOWER CHANCES WILL THEN DECREASE OVERNIGHT IN THE WAKE OF THE DISTURBANCE...LEAVING PARTLY/MOSTLY CLOUDY SKIES ACROSS THE FORECAST AREA. GENERALLY EXPECT PARTLY SUNNY SKIES ACROSS THE REGION TUESDAY...WITH AN ISOLATED/SCATTERED AFTERNOON SHOWER OR THUNDERSTORM POSSIBLE. LOW TEMPERATURES TONIGHT WILL RANGE FROM THE LOWER TO MID 60S ACROSS THE FORECAST AREA. HIGH TEMPERATURES TUESDAY WILL GENERALLY RANGE FROM THE LOWER TO MID 80S ACROSS THE FORECAST AREA...WITH COOLER READINGS ALONG THE IMMEDIATE DOWNEAST COAST. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... THE SHORT TERM PERIOD STARTS OUT UNSETTLED WITH AN UPPER LEVEL SHORTWAVE AND SFC COLD FRONT MOVING ACROSS NEW ENGLAND. THESE TWO FEATURES WILL SPAWN SCTD SHOWERS AND TSTMS ACROSS PARTS OF NEW ENGLAND...WITH THE BEST CHANCE OF PRECIP EXPECTED WED NIGHT FROM THE CROWN OF MAINE SWRD ACROSS WRN MAINE INTO NRN NEW HAMPSHIRE AND VERMONT. SUBSIDENCE AND DRIER AIR WILL MOVE OVER MUCH OF MAINE ON THURSDAY...WITH THE MAIN AREA OF PRECIP SHIFTING EWRD ACROSS NB/NS AND THE ATLANTIC OCEAN. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... UPPER TROUGH WILL SWING THROUGH THE REGION AS SYSTEM CONTINUES TO PROGRESS EAST OF THE REGION THURSDAY NIGHT. THIS WILL ALLOW FOR SURFACE HIGH PRESSURE TO BEGIN BUILDING EAST ACROSS THE REGION THURSDAY NIGHT INTO FRIDAY. THIS WILL ALSO BRING MOSTLY SUNNY SKIES FOR FRIDAY AS UPPER LEVEL FLOW FLATTENS. THIS IS EXPECTED TO CONTINUE INTO FRIDAY NIGHT WITH INCREASING CLOUDS LATER SATURDAY INTO SATURDAY NIGHT AS SURFACE HIGH BREAKS DOWN. ONCE THIS HIGH BREAKS DOWN WE WILL INCREASE SW FLOW THEREFORE INCREASING MOISTURE ACROSS THE REGION. CONSEQUENTLY THIS WILL BRING INCREASED CHANCES OF SHOWERS AND AFTERNOON THUNDERSTORMS ACROSS THE REGION WITH GOOD UPPER LEVEL DIFFLUENCE ALOFT GOING INTO SUNDAY. THESE SHOWER AND THUNDERSTORM CHANCES WILL CONTINUE AS FRONTAL BOUNDARY APPROACHES THE REGION AS WE GO INTO MONDAY AFTERNOON. TEMPERATURES THROUGH THE PERIOD ARE EXPECTED TO BE NEAR TO A BIT ABOVE NORMAL. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... NEAR TERM: GENERALLY VFR/MVFR CONDITIONS WILL OCCUR ACROSS THE REGION EARLY THIS EVENING...WITH CONDITIONS LOWERING TO IFR/LIFR LEVELS LATER THIS EVENING. MVFR/IFR CONDITIONS ARE EXPECTED ACROSS THE REGION EARLY TUESDAY...IMPROVING TO VFR LEVELS TUESDAY AFTERNOON. HOWEVER...VARIABLE CONDITIONS COULD OCCUR IN THE VICINITY OF ANY SHOWERS OR THUNDERSTORMS TUESDAY AFTERNOON. SHORT TERM: AREAS OF MVFR CONDITIONS WILL AFFECT NRN AND WRN MAINE WEDNESDAY NIGHT IN ASSOCIATION WITH SHORTWAVE AND FRONT MOVING ACROSS NEW ENGLAND. OTHERWISE...PREVAILING CONDITIONS SHOULD BE VFR. && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS IS IN EFFECT FOR MUCH OF THE WATERS...WITH THE EXCEPTION OF THE INTRACOASTAL WATERS...TONIGHT THROUGH TUESDAY AFTERNOON. VISIBILITIES COULD BE REDUCED IN SHOWERS AND PATCHY FOG TONIGHT. SHORT TERM: MADE LITTLE TO NO CHANGES TO GOING FORECAST FOR WINDS AND WAVES OVER THE COASTAL WATER. SRLY WINDS AHEAD OF THE FRONT WILL INCREASE TO 10 TO 15 KTS ON WEDNESDAY...THEN BECOME WEST AFTER THE FRONT MOVES THROUGH ON THURSDAY. DUE TO COLD WATER RESULTING IN A SHALLOW INVERSION...WINDS AND AS A RESULT WAVE HEIGHTS WILL BE LESS THAN THE WAVE MODELS ARE FORECASTING. HOWEVER BORDERLINE WAVE/WIND CONDITIONS DURING THIS TIME FRAME MAY NECESSITATE A SMALL CRAFT ADVISORY FOR OUR COASTAL WATERS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM EDT TUESDAY FOR ANZ050-051. && $$ NEAR TERM...VJN SHORT TERM...RB LONG TERM...JORDAN AVIATION...VJN/RB MARINE...VJN/RB
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1145 AM EDT TUE JUL 8 2014 .SYNOPSIS... SHOWERS AND THUNDERSTORMS WILL ACCOMPANY A COLD FRONT PASSAGE TODAY AND THIS EVENING. A SECONDARY FRONT WILL PUSH THROUGH WEDNESDAY BEFORE HIGH PRESSURE BUILDS OVERHEAD FOR THE REMAINDER OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... REMNANTS OF THE MCS WILL CONTINUE TO SHIFT NORTHEASTWARD THROUGH THE REST OF THIS MORNING. HOWEVER...STORMS HAVE ALREADY DEVELOPED ALONG THE SOUTHERN FLANK OF THIS SYSTEM OVER WESTERN OHIO. BASED ON THE MOST RECENT HRRR DATA...THIS LOOKS TO BE WHERE FURTHER DEVELOPMENT WILL OCCUR AS THE SHORTWAVE/FRONT ASSOCIATED WITH THIS SHIFTS TOWARDS THE REGION. THE BEST TIMING FOR CONVECTIVE DEVELOPMENT BASED ON THE HI RES MODELS AND THE NAM SUGGEST AS EARLY AS 1-2PM. WHILE SHEAR WILL BE INCREASING...ESPECIALLY OVER THE NORTHERN HALF OF THE CWA DUE TO STRENGTHENING LOW-MID LEVEL JET DYNAMICS...THERE ARE CONCERNS THAT THE ABUNDANCE OF CLOUD COVER WILL LIMIT HEATING AND DESTABILIZATION. STILL...WITH SUCH STRONG UPPER LEVEL SUPPORT...EVEN MODEST CAPE SHOULD SUPPORT SOME STRONG TO SEVERE STORMS. WILL CONTINUE TO MONITOR THE CONDITIONS AS WE GO INTO THE AFTERNOON AND HIGHLIGHT WIND AS THE PRIMARY THREAT...ALTHOUGH AN ISOLATED TORNADO COULD NOT BE RULED OUT. PWAT VALUES WILL ALSO BE IN THE 1.50-1.75 RANGE THROUGH THIS EVENING...SO HEAVY DOWNPOURS AND SOME LOCALIZED FLOODING COULD BE POSSIBLE. ALL OF THE MODEL GUIDANCE SUGGESTS THAT A SECOND LINE OF SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE LATER THIS EVENING WITH ANOTHER WEAK SHORTWAVE PASSAGE. CONSIDERING ITS LATER TIMING...DO NOT EXPECT THERE TO BE AS MUCH OF A THREAT FOR SEVERE WITH IT...BUT WILL KEEP LIKELY POPS THROUGH THE FIRST HALF OF TONIGHT. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/... INSTABILITY WITH COLDER AIR ALOFT WITH TROUGHING OVER THE REGION WILL CONTINUE THE CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE DAY ON WEDNESDAY BEFORE HIGH PRESSURE BEGINS TO REGAIN CONTROL WEDNESDAY NIGHT. SFC HIGH PRESSURE BUILDS IN OVER THE SRN GREAT LAKES WEDS NIGHT INTO THURS WITH DRYING EXPECTED. DAYTIME HIGHS SHOULD TOP OUT NEAR AVERAGE FOR THIS TIME OF YEAR...WHILE NIGHTTIME LOWS THURS AND FRI COULD BE A FEW DEGREES COOLER THAN AVERAGE AS MOSTLY CLEAR SKIES AND CALM WINDS WILL ALLOW ENHANCED RADIATIONAL COOLING. && .LONG TERM /SATURDAY THROUGH MONDAY/... SFC HIGH GETS SQUEEZED OUT OF THE AREA SAT AS A WEAK AND RELATIVELY DRY FRONT SAGS SOUTHWARD THROUGH THE GREAT LAKES AND APPROACHES FOR SUN. MODELS HAVING A DIFFICULT TIME CONVERGING ON A SINGLE SOLN NEXT WEEKEND...BUT THEY DO DEPICT THE FRONT REINFORCING THE BROAD UPPER TROF OVER THE ERN CONUS. COOLER AIR SHOULD BEGIN TO SEEP IN FROM THE NORTHWEST UNDER THIS REGIME...WITH MULTIPLE DISTURBANCES PASSING THROUGH THE TROF. TRENDED TEMPS A BIT LOWER HEADING INTO NEXT WEEKEND...AND CONTINUED WITH LESS DETERMINISTIC POPS...ORIENTING HIGHER CHC POPS ALONG THE FRONT. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... PTCHY MVFR SC WL CONT THIS MRNG BEFORE AN IMPROVEMENT TO VFR. AN MCS ACRS OH SHOULD CONT TO WKN PER RECENT VIL LOOPS AND STLT TRENDS. EXP REDEVELOPMENT OF A BKN LN OF TSTMS LT THIS MRNG INTO THE AFTN AS A CDFNT ADVNS ACRS THE RGN...WITH A PD OF AT LEAST MVFR RSTRNS AND GUSTY WNDS. EXP A LT AFTN/EVE FROPA WITH GENL VFR CONDS TO FOLLOW. .OUTLOOK.../WEDNESDAY THROUGH SATURDAY/... RSTRNS ARE PSBL IN SCT TSTMS WED WITH A CROSSING DISTURBANCE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
122 AM EDT TUE JUL 8 2014 .SYNOPSIS... HIGH PRESSURE BECOMES ANCHORED OFF THE SOUTHEAST COAST TONIGHT THROUGH WEDNESDAY. A WEAK FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST LATER WEDNESDAY AND LINGERS OVER THE MID ATLANTIC REGION INTO THURSDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... LATEST WX ANALYSIS FEATURES SFC HIGH PRESSURE CENTERED WELL OFFSHORE...RIDGING BACK TOWARDS THE SOUTHEAST COAST. TO THE NW, LOW PRESSURE WAS ANALYZED OVER ONTARIO, WITH THE SFC COLD FRONT SNAKING SWWD BACK INTO THE MID MO VLY AND CENTRAL PLAINS. ALOFT, EARLY EVENING GOES WV IMAGERY SHOWS A STRONG SHORTWAVE EMBEDDED IN BROAD UPPER LEVEL TROUGH OVER AND N OF THE GREAT LAKES/UPPER MIDWEST. MEANWHILE, UPPER RIDGING PERSISTS IN THE SUBTROPICAL WESTERN ATLANTIC. NO MAJOR CHANGES NEEDED THIS EVENING. SCT TO BKN CU OF LATE THIS AFTN HAS LARGELY DISSIPATED AS EXPECTED EARLY THIS EVENING. GENERALLY CLEAR/MOSTLY CLEAR AND MILD OVERNIGHT WITH EARLY MORNING LOW TEMPERATURES TO AVERAGE IN THE LOW/MID 70S. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/... THE UPPER RIDGE/SURFACE HIGH PRESSURE HOLD STRONG OFF THE COAST TUESDAY...WITH THE FRONT REMAINING WELL NW OF THE LOCAL AREA. THIS WILL RESULT IN DEEP LAYERED SSW FLOW AND HOT TEMPERATURES. HIGHS ARE EXPECTED TO AVERAGE IN THE MID/UPPER 90S...WITH ONLY FEW-SCT AFTERNOON CU. HUMIDITY VALUES WILL REMAIN MODEST AS AFTERNOON DEWPOINTS MIX DOWN INTO THE MID 60S. THIS WILL KEEP HEAT INDICES AOB 100. THERE IS NOT MUCH OF A TRIGGER FOR CONVECTION AND FORECAST SOUNDINGS INDICATE A RATHER PROMINENT SUBSIDENCE INVERSION THROUGH THE DAY. AN ISO TSTM COULD DRIFT OFF THE HIGHER TERRAIN INTO FAR N/NW PORTIONS OF THE AREA TUESDAY EVENING. OTHERWISE...EXPECT ANOTHER WARM NIGHT UNDER A MOSTLY CLEAR TO PARTLY CLOUDY SKY. LOWS SHOULD AVERAGE IN THE LOW/MID 70S. THE COLD FRONT CROSSES THE MOUNTAINS AND SLUMPS INTO THE AREA FROM THE WNW WEDNESDAY. THIS WILL INTERACT WITH THE HOT AND MODERATELY HUMID AIRMASS OVER THE PIEDMONT/COASTAL PLAIN BRINGING A 30-40% CHC OF SHOWERS/TSTMS MAINLY DURING THE AFTERNOON AND EVENING HOURS. AN FEW STRONG WIND GUSTS ARE POSSIBLE AS CONVECTION DEVELOPS OVER A DEEP WELL MIXED BOUNDARY LAYER. HOWEVER...WIDESPREAD SEVERE WEATHER IS NOT EXPECTED. HIGHS SHOULD BE IN THE LOW/MID 90S...AND ONCE AGAIN HUMIDITY LEVELS WILL BE LOW ENOUGH TO KEEP HEAT INDICES AOB 100. THE BOUNDARY LINGERS OVER THE REGION THURSDAY...WITH A 30-40% CHC OF MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS CONTINUING. HIGHS SHOULD DROP BACK INTO THE UPPER 80S TO AROUND 90...AFTER MORNING LOWS IN THE LOW/MID 70S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... VERY WARM AND RATHER HUMID CONDITIONS WILL DOMINATE THE EXTENDED PERIOD. UPR TROF WILL APPROACH AND PUSH ACRS THE AREA THU NGT INTO SAT...NUDGING ONE FRNTL BOUNDARY EVENTUALLY OFF THE CST. ANOTHER FRONT WILL THEN PUSH INTO THE REGION MON AND MON NGT. WILL HAVE 40 POPS MAINLY OVR ERN/SE AREAS THU NGT INTO FRI...THEN DIMINISHING TO 30 OR 20 POPS FRI AFTN INTO SAT. INCREASE POPS TO 30 PERCENT EVERYWHERE FOR SUN AFTN/EVENG...DUE TO HIGHER TEMPS AND A LEE TROF SETTING UP OVR THE REGION. WILL HAVE 30 POPS AGAIN FOR MON AFTN THRU MON NGT...AS FRNTL BOUNDARY PUSHES INTO THE AREA. MIN TEMPS WILL RANGE FM THE MID 60S TO LWR 70S THRU THE PERIOD...WITH MAX TEMPS RANGING FM THE MID 80S TO LWR 90S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... VFR CONDITIONS EXPECTED THROUGH FCST PERIOD. CONCERN TODAY WILL BE THE GUSTY SW WINDS (15-25 KTS) AS A RESPECTABLE PRESSURE GRADIENT FOR JULY PROGGED AS SFC TROF REMAINS NRLY STNRY ACROSS THE PIEDMONT. ISOLATED CONVECTION PSBL MAINLY NW OF A RIC-SBY LINE BUT CHC NOT HIG ENUF TO INCLUDE IN FCST ATTM. OUTLOOK...A COLD FRONT APPROACHES FROM THE NW WEDNESDAY AND SETTLES OVER THE REGION THURSDAY AND FRIDAY. THERE WILL BE A CHANCE FOR AFTN AND EVENING TSTMS WEDNESDAY THROUGH FRIDAY. A BIT DRIER PATTERN IS INDICATED SATURDAY. && .MARINE... 7 PM UPDATE... A SCA IS IN EFFECT THROUGH 10 AM TUESDAY FOR THE BAY AND THE LOWER JAMES RIVER. SW WINDS WILL OCCASIONALLY GUST TO AROUND 20 KNOTS OVER THESE WATERS. THE RAP AND HRRR AGAIN HOLD ONTO SUSTAINED WINDS OF NEAR 20 KNOTS THROUGH 12Z THEN DROP THEM OFF. THIS IS VERY SIMILAR TO MONDAY MORNING BUT NOT NECESSARILY A SIMILAR PATTERN. WINDS OVER LAND WERE GUSTY EARLY MONDAY EVENING AND SOME OF THESE GUSTS HAVE SPREAD INTO THE WRN PORTIONS OF THE WATERS. WITH THE HI RES MODELS INDICATING SCA CONDITIONS ONCE AGAIN...IT SEEMED PRUDENT TO ISSUE THE SCA. WILL ASSESS THE NEED FOR SCA IN CURRITUCK SOUND LATER THIS EVENING. FROM PREVIOUS DISCUSSION... SSW WINDS 10 TO 20 KT WILL CONTINUE TO DOMINATE THE WTRS TNGT THRU WED WITH SEAS 2 TO 4 FT OVR THE CSTL WTRS...ALTHO SEAS COULD REACH 5 OR 6 FT OVR THE NRN CSTL WTRS TUE NGT INTO WED. WAVES WILL RANGE FM 1 TO 3 FT. A COLD FRNT WILL SLOWLY DROP SE ACRS THE WTRS WED EVENG THRU FRI. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...MODERATE RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR MDZ025. NC...MODERATE RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR NCZ102. VA...MODERATE RIP CURRENT RISK FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING FOR VAZ098>100. MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EDT THIS MORNING FOR ANZ630>632-634-638. && $$ SYNOPSIS...AJZ/ALB NEAR TERM...AJZ/MAM SHORT TERM...AJZ/ALB LONG TERM...TMG AVIATION...MPR MARINE...TMG/LSA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EDT TUE JUL 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 425 PM EDT TUE JUL 8 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA AND A DOWNSTREAM TROF WITH AXIS EXTENDING FROM NCNTRL CANADA INTO THE GREAT LAKES. ONE VIGOROUS SHORTWAVE MOVING THRU THE TROF BROUGHT SHRA AND SOME TSRA TO MUCH OF THE FCST AREA LAST NIGHT INTO THE MORNING HRS. THAT WAVE IS NOW E OF LAKE SUPERIOR. UPSTREAM...THERE ARE A PAIR OF SHORTWAVES...ONE NEAR LAKE WINNIPEG AND THE OTHER JUST TO THE E IN NRN ONTARIO. NEITHER ARE AS STRONG AS THE ONE THAT AFFECTED THE AREA EARLIER TODAY. THE WAVE NEAR LAKE WINNIPEG IS THE STRONGER OF THE TWO AND WILL BE THE MAIN PLAYER IN THE WEATHER HERE TONIGHT. IN THE WAKE OF THE SHORTWAVE THAT PASSED EARLIER TODAY... CLOUDS HAVE HELD TOUGH ACROSS MUCH OF THE AREA...AND THIS HAS RESULTED IN A VERY COOL DAY FOR EARLY JULY STANDARDS. AS OF 19Z... READINGS WERE STILL ONLY HOVERING AROUND 50F NEAR LAKE SUPERIOR AND AROUND 60/LWR 60S ACROSS SCNTRL UPPER MI. SO FAR...TEMP HAS ONLY REACHED 54F HERE AT THE NWS OFFICE. RECORD LOW MAX TEMP FOR TODAY IS 60F. IF LOW STRATUS HANGS AROUND THRU SUNSET...THAT RECORD WILL FALL. WHERE CLOUDS HAVE BROKEN TO ALLOW FOR SUNSHINE FROM NE MN INTO NRN WI...BUILD UP OF A LITTLE INSTABILITY UNDER COOL CYCLONIC NW FLOW COMBINED WITH A SUBTLE SHORTWAVE HAS ALLOWED -SHRA/ISOLD TSRA TO DEVELOP. THOSE SHRA HAVE BEEN BRUSHING MENOMINEE COUNTY. OTHERWISE...ISOLD -SHRA/PATCHY -DZ HAVE BEEN OCCURRING ACROSS THE AREA TODAY. ISOLD -SHRA MAY LINGER NEAR THE WI/MI BORDER INTO THE EARLY EVENING HRS. OTHERWISE...ATTENTION TURNS TO THE NW. ALTHOUGH UPSTREAM SHORTWAVES WILL BE PASSING ACROSS THE UPPER LAKES DURING THE NIGHT WHEN INSTABILITY IS DIMINISHING TOWARD DIURNAL MIN...EXPECT SOME SHRA TO PERSIST NEAR THE TRACK OF THE WAVES...PARTICULARLY NEAR THE AFORMENTIONED STRONGER WRN WAVE. THIS SHOULD PUT BEST POTENTIAL FOR ISOLD/SCT SHRA ROUGHLY OVER THE W HALF OF UPPER MI. SINCE SHORTWAVE IS WEAKER THAN LAST NIGHTS WAVE...MUCAPE IS UNDER 100J/KG... SHOWALTER INDEX IS ABOVE 0 AND NO TSRA HAVE DEVELOPED WITH WAVE SO FAR THIS AFTN...HAVE REMOVED ANY MENTION OF THUNDER TONIGHT. ISOLD -SHRA MAY LINGER THRU WED MORNING WITH WEAK TRAILING SHORTWAVE ENERGY. HOWEVER...WITH SOLID HEIGHT RISES TAKING OVER DURING THE DAY (12HR 500MB HEIGHTS RISE 70-90M) ALONG WITH COLUMN DRYING...EXPECT A DRYING TREND WED. THERE MAY BE A FEW AFTN -SHRA OVER THE SCNTRL AS LAKE MICHIGAN LAKE BREEZE TRIES TO MOVE INLAND...SO ISOLD -SHRA MENTION WAS LINGERED INTO THE AFTN IN THAT AREA. AS OPPOSED TO TODAY...EXPECT MORE SUNSHINE TO DEVELOP WED UNDER DRYING/HEIGHT RISES. THIS WILL HELP BOOST TEMPS TOWARD 70F INLAND. WHERE WINDS ARE ONSHORE THRU THE DAY...TEMPS ALONG LAKE SUPERIOR WILL NOT GET OUT OF THE 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 326 PM EDT TUE JUL 8 2014 LARGE SCALE PATTERN LOOKS SIMILAR TO WHAT WAS OCCURRING THIS TIME LAST WEEK. TROUGHING TO START THE WEEK THEN RELAXING HEIGHTS MORE ZONAL FLOW LATE WEEK INTO THE WEEKEND. SEEMS THIS PATTERN CHANGES BACK TO TROUGHING QUICKER THOUGH WITH ECMWF/GFS/GEM-NH TRENDING BACK TO TROUGHING BY SUNDAY AND PERSISTING INTO EARLY NEXT WEEK. PRIMARY RAIN CHANCES OCCUR AS THE FLOW GOES ZONAL...FRIDAY INTO SATURDAY. DECENT AGREEMENT THAT MAIN COLD FROPA OCCURS LATE FRIDAY NIGHT INTO SATURDAY. DPROG/DT...SEEING HOW THE MODELS ARE CHANGING OVER THEIR RECENT RUNS...INDICATES STRONG CONSISTENCY FM THE MODELS IN MASS FIELDS /MID-LEVEL HEIGHTS AND MSLP/ THROUGH SATURDAY. AHEAD OF THE COLD FROPA ON SATURDAY...HIGH PRESSURE AND MAINLY DRY WEATHER IS OVER THE REGION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. LOW TEMPS COOLEST ON WED NIGHT WITH PWATS AROUND 50 PCT OF NORMAL BENEATH THE RIDGE AXIS. FAVORED COLD SPOTS INTERIOR MAY SEE LOWS AROUND 40 DEGREES. OTHERWISE...READINGS WILL BE IN THE 40S TO AROUND 50. WARMER NIGHT EXPECTED ON THURSDAY NIGHT AS SOUTHERLY RETURN FLOW DEVELOPS AS RIDGE AXIS SLIDES EAST. MAX TEMPS ON THURSDAY AROUND NORMAL IN THE MID TO UPPER 70S...WITH ONLY LOCAL COOLING NEAR IMMEDIATE GREAT LAKES SHORES. CLOUDS WILL INCREASE LATER THURSDAY NIGHT AS SHORTWAVES BEGIN TO WORK ACROSS NORTHERN PLAINS AND UPPER GREAT LAKES IN A MORE WESTERLY FLOW ALOFT. LEAD SHORTWAVE CURRENTLY OFFSHORE OF OREGON SLIDES ACROSS ON FRIDAY. STRONGER WAVE IS FORECAST TO CROSS MANTIOBA AND NORTHWEST ONTARIO. H85-H7 MOISTURE TRANSPORT LOOKS SPLIT IN TWO AREAS...STRONGEST CLOSER TO THE CANADIAN TROUGH. INSTABILITY AXIS BOTH AT SFC AND ALOFT ELEVATED LAGS BOTH WAVES SO NOT EXPECTING STRONG STORMS LATER THU NIGHT OR FRIDAY. THETA-E ADVECTION RAMPS UP FRIDAY NIGHT INTO SATURDAY MORNING AHEAD OF COLD FRONT WHICH WILL SUPPORT GREATER COVERAGE OF SHRA/TSRA. INSTABILITY REMAINS ONLY MARGINAL WITH 200-400J/KG OF 1-6KM MUCAPE AS GREATEST MLCAPE AND 1-6KM MUCAPE SETTLES MORE SOUTH INTO MIDDLE MISSISSIPPI VALLEY THAN EAST ACROSS THE GREAT LAKES. DEEP LAYER SHEAR VALUES ARE UP TO 30 KTS FRIDAY NIGHT...SO CANNOT COUNT OUT SOME STRONGER STORMS. SEVERE RISK DOES APPEAR PRETTY MARGINAL. DEEP LAYER SHEAR INCREASES TO 40+ KTS BY SATURDAY AFTN. 12Z ECMWF INDICATES MORE MLCAPE THAN EARLIER RUNS...CENTERED OVER CNTRL UPR MICHIGAN IN THE AFTN. LOOKS AS IF THE COLD FRONT MAY BE SLIGHTLY SLOWER. AS LONG AS THE SHRA/TSRA FROM FRIDAY NIGHT AND ASSOCIATED COOLING/STABILIZING AFFECTS ARE OUT OF THE WAY IN TIME...COULD SEE ISOLD STRONG OR SEVERE STORMS OVR CNTRL UPR MICHIGAN SATURDAY AFTN IF THERE IS ENOUGH SUNSHINE. H7 WINDS ARE MORE WESTERLY. ATTM BASED ON EXPECTED POSITION OF COLD FRONT AND A MORE WEST TO EAST MEAN STORM MOTION...LOOKS LIKE GREATEST RISK FOR STRONGER STORMS WOULD BE OVER SCNTRL UPR MICHIGAN. WHATEVER SHRA/TSRA ARE AROUND SATURDAY AFTERNOON...SHOULD DIMINISH/END LATER SATURDAY NIGHT. MODEL CONSISTENCY BECOMES MORE JUMPY SUNDAY/MONDAY...BUT LAST COUPLE RUNS OF EACH MODEL IS HEADING TOWARD MORE TROUGHING/COOLER WEATHER. PRIMARY ISSUE IS POSSIBLE DEVELOPMENT OF STRONGER SFC LOW PRESSURE ON LEADING EDGE OF MID-LEVEL TROUGH SATURDAY NIGHT INTO SUNDAY. RECENT RUNS OF GEM-NH STILL HANGING ON TO THIS IDEA WHILE 06Z GFS WAS THE FIRST GFS RUN SINCE JULY 7/12Z TO SHOW SIMILAR SOLN. 12Z GFS DOES NOT HAVE IT AGAIN. ECMWF SHOWED STRONGER LOW ON THE JULY 6/12Z RUN...BUT HAS SINCE BACKED AWAY. BY EARLY NEXT WEEK...TREND IS CERTAINLY THERE FOR A RETURN TO TROUGHING AND BLO NORMAL TEMPS...LIKELY OVER 20 DEGREES BLO NORMAL FOR DAYTIME HIGHS NEAR LK SUPERIOR. CORE OF COOLEST AIR AT H85 OVER MANITOBA AND ONTARIO BOTTOMS OUT AROUND 0C ON THE ECMWF AND AROUND +2C ON THE GFS ON MONDAY. UPPER LOW CENTER SETTLES ACROSS GREAT LAKES BY NEXT TUESDAY WITH H85 TEMPS STAYING BLO +5C AND PLENTY OF H85-H7 MOISTURE. SFC LOW FORECAST TO BE EAST OF LK SUPERIOR REGION... SO NORTH WINDS WILL KEEP UPPER GREAT LAKES VERY COOL. RECORD LOW MAXES FOR MID JULY ARE IN THE UPPER 50S TO LOWER 60S...BUT SOME VALUES IN JULY ARE EVEN IN THE LOWER 50S. MAY SEE SOME TEMPS EARLY NEXT WEEK COME CLOSE TO THESE LOWER READINGS. IT IS CERTAINLY WITHIN THE REALM OF POSSIBILITY. CHANCES OF SEEING CLOUDS AND SHOWERS IN THE PATTERN PRETTY HIGH...SO THAT WOULD ONLY HELP KEEP TEMPS ON THE COOL SIDE. PROBABLY GOES WITHOUT SAYING...BUT NO REAL STRETCHES OF WELL ABOVE NORMAL TEMPS ARE SEEN ANYTIME IN THE MEDIUM RANGE TIME PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 141 PM EDT TUE JUL 8 2014 DESPITE HIGH SUN ANGLE AT THIS TIME OF YEAR...LOW CLOUDS (IFR/LIFR CONDITIONS) HAVE PERSISTED INTO THE EARLY AFTN AT KIWD/KCMX/KSAW. STILL EXPECT IMPROVEMENT AS DAYTIME HEATING CONTINUES TO WORK AT RAISING CIGS FROM THE CLOUD DECK EDGES. ALL TERMINALS SHOULD BE VFR BY LATE AFTN. BEING FARTHEST FROM CLOUD BREAKS PER VIS SATELLITE IMAGERY AND DUE TO CHILLY UPSLOPE FLOW OFF LAKE SUPERIOR...KSAW WILL SEE SLOWEST IMPROVEMENT THIS AFTN. NOT OUT OF THE QUESTION THAT KSAW WILL IMPROVE SLOWER THAN REFLECTED IN THIS FCST. VFR CONDITIONS SHOULD PREVAIL AT ALL TERMINALS TONIGHT INTO WED. DISTURBANCE DROPPING INTO THE UPPER LAKES MAY BRING SOME -SHRA TO KIWD/KCMX LATE THIS EVENING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 326 PM EDT TUE JUL 8 2014 WINDS ARE EXPECTED TO STAY BELOW 25 KTS THROUGH THE PERIOD OUTSIDE OF ANY STRONGER THUNDERSTORMS. GREATEST CHANCES FOR THUNDERSTORMS WILL BE FRIDAY NIGHT INTO SATURDAY AS A COLD FRONT GRADUALLY CROSSES LAKE SUPERIOR. COULD SEE DENSE FOG AT TIMES FOR THE UPCOMING WEEKEND OVER NORTHERN SECTIONS AS SOUTH WINDS TRANSPORT MORE HUMID AIR ACROSS LK SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...JLA AVIATION...ROLFSON MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1206 AM EDT TUE JUL 8 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 413 PM EDT MON JUL 7 2014 WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW BETWEEN A RIDGE OVER THE WRN CONUS AND SRN PLAINS AND A TROUGH THROUGH NRN MANITOBA INTO NRN ONTARIO. ONE WEAK SHRTWV IN CNTRL MN SUPORTED SCT SHRA/TSRA FROM ERN MN INTO CNTRL WI...WHILE A MORE PROMINENT SHRTWV WAS LOCATED OVER WRN NORTH DAKOTA. AT THE SFC...GUSTY WNW WINDS PREVAILED WITH A 995 MB LOW PRES OVER NRN ONTARIO(NEAR CYTS). TONIGHT...THE HIGHER RES MODELS HAVE TRENDED FARTHER SOUTH WITH THE THE HEAVIER PCPN AND ASSOCIATED PCPN CHANCES WHERE THE GREATER FORCING(700-300 MB QVECTOR CONV AND UPPER LEVEL DIV) AND INSTABILITY IS LOCATED AS THE ND SHRTWV MOVES TOWARD THE AREA. NEVERTHELESS...NMS SHRA ARE EXPECTED TO CLOSER TO THE WI BORDER BY LATE EVENING AND OVERNIGHT WITH CHANCE POPS FARTHER NORTH TOWARD LAKE SUPERIOR EAST OF THE KEWEENAW. THUNDER WAS ALSO ONLY INDCLUDED ACROSS THE FAR SOUTH. TUESDAY...EXPECT THAT HIGHER PCPN CHANCES IN THE MORNING TO DIMINISH BY AFTERNOON AS THE SHRTWV MOVES OFF TO THE EAST. ADDITIONAL PCPN AMOUNTS SHOULD AGAIN BE GREATEST OVER SRN CWA. THE COMBINATION OF THICKER CLOUDS AND NRLY LOW LEVEL FLOW WILL KEEP TEMPS WELL BELOW NORMAL WITH UPPER 50S TO MID 60S NORTH TO THE MID 60S SOUTH. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 416 PM EDT MON JUL 7 2014 AN UPPER TROUGH CURRENTLY OVER THE UPPER GREAT LAKES REGION WILL BE REINFORCED TONIGHT AND TOMORROW BY A SHORTWAVE (CURRENTLY NEAR LAKE WINNIPEG) THAT WILL DROP SOUTHEAST THROUGH THE AREA. THIS FIRST WAVE WILL SHIFT OUT OF THE AREA ON TUESDAY...BUT ANOTHER WAVE WILL BE DROPPING SOUTHEAST FROM LAKE WINNIPEG AT 00Z WEDNESDAY AND ACROSS THE CWA LATE TUESDAY EVENING THROUGH WEDNESDAY MORNING. THERE ARE SOME DIFFERENCES IN THE MODELS WITH THE TRACK OF THE SHORTWAVE...WITH THE GENERAL CONSENSUS OF IT MOVING ACROSS THE SOUTHWEST HALF OF THE CWA. WILL TRANSITION CHANCE POPS ACROSS THE WESTERN TWO THIRDS OF THE AREA FROM NORTHWEST TO SOUTHEAST DURING THAT TIME. THERE IS LIMITED CAPE...BUT THE STRENGTH OF THE SHORTWAVE AND POCKET OF STEEPER LAPSE RATES (700-500MB AT 6-6.5C/KM) THOUGHT THERE COULD BE AN ISOLATED RUMBLE OF THUNDER AND HAVE SHOWN SLIGHT CHANCE OVER THE SOUTHWEST HALF OF THE CWA AS IT SWEEPS THROUGH. BEHIND THIS WAVE...HIGH PRESSURE WILL BUILD OVER THE UPPER GREAT LAKES REGION FOR WEDNESDAY AFTERNOON AND REMAIN THROUGH THURSDAY NIGHT. 850MB TEMPS ARE COOLING TO 6-7C ON WEDNESDAY...AND COMBINED WITH MORNING CLOUDS/RAIN AND NORTHERLY WINDS OFF LAKE SUPERIOR...IT WILL LEAD TO A BELOW NORMAL DAY ACROSS THE U.P. EXPECT MOST LOCATIONS TO SEE HIGHS IN THE 60S...WITH COOLER VALUES EAST NEAR LAKE SUPERIOR AND MAYBE REACHING 70 NEAR THE WISCONSIN BORDER WITH SOME AFTERNOON SUNSHINE. CLEAR SKIES...LIGHT WINDS...AND PWATS AROUND 45 PERCENT OF NORMAL UNDER THE HIGH MOVING THROUGH SHOULD LEAD TO A COOL NIGHT OVER SOME OF THE INTERIOR COLD SPOTS WEDNESDAY NIGHT. HAVE LOWERED INTERIOR TEMPERATURES TOWARDS THE LOW END OF GUIDANCE AND HAVE A FEW LOCATIONS RIGHT AROUND 40. EXPECT TEMPERATURES TO TREND BACK TOWARDS NORMAL ON THURSDAY WITH ABUNDANT SUNSHINE AND INTO THE LOW-MID 70S OVER INTERIOR LOCATIONS. WITH LAKE BREEZES EXPECTED ON THURSDAY...WILL SEE COOLER TEMPERATURES OVER THE EAST NEAR LAKE SUPERIOR/MICHIGAN. THE NORTHWEST FLOW ALOFT WILL GIVE WAY DURING THIS PERIOD...AS THE NEXT WAVE ROUNDING THE UPPER RIDGE OVER THE PACIFIC NORTHWEST AND AFFECTS THE AREA FOR FRIDAY AND FRIDAY NIGHT. THAT NEXT WAVE WILL PUSH A LOW EAST ACROSS NORTHERN MANITOBA...WITH A COLD FRONT STRETCHING SOUTH INTO THE UPPER MISSISSIPPI VALLEY FRIDAY MORNING. A SHORTWAVE SLIDING EAST OUT OF THE DAKOTAS FRIDAY MORNING WILL LEAD TO SHOWERS/THUNDERSTORMS DEVELOPING AHEAD OF THE COLD FRONT AND MOVING FROM WEST TO EAST THROUGH THE CWA FRIDAY INTO FRIDAY NIGHT. WILL SHOW INCREASING CHANCES DURING THAT PERIOD AND THEN DIMINISHING LATE IN THE NIGHT AND INTO THE NEXT MORNING. DIURNAL HEATING OUT AHEAD OF THE FRONT ON FRIDAY AFTERNOON SHOULD LEAD TO SOME THUNDERSTORMS OVER THE AREA FRIDAY AFTERNOON/EVENING. DETERMINISTIC MODELS VARY BEHIND THIS WAVE/FRONT WITH THE HANDLING OF THE UPPER TROUGH...BUT THE LASTEST TREND IS FOR IT TO AMPLIFY OVER THE UPPER GREAT LAKES FOR THE SECOND HALF OF THE WEEKEND AND INTO NEXT WEEK. THIS WOULD LEAD TO A COOLER THAN NORMAL PERIOD THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1206 AM EDT TUE JUL 8 2014 VFR CONDITIONS WILL CONTINUE AT ALL SITES INTO EARLY MORNING. THE NEXT DISTURBANCE WILL MOVE INTO THE REGION AND BRING A CHANCE OF SHOWERS OVERNIGHT. AS WINDS SHIFT NE LATE TONIGHT LOOK FOR MVFR CLOUDS TO DEVELOP AT KIWD DROPPING TO IFR TUE MORNING BEFORE DRIER AIR MOVES IN AND VFR CONDITIONS RETURN BY MID TUE AFTERNOON. RAIN WILL AGAIN ARRIVE IN THE EVENING THERE WITH MVFR CONDITIONS EXPECTED TO REDEVELOP AGAIN. CIGS WILL GO TO LIFR IN THE RAIN OVERNIGHT AT SAW WITH UPSLOPE NORTHEAST FLOW OFF OF LAKE SUPERIOR LASTING THROUGH THE MORNING BEFORE DRIER AIR AND IMPROVING CONDITIONS ARRIVE. AT KCMX...MVFR CONDITIONS WILL DEVELOP BY TUE MORNING BEFORE DRIER AIR ARRIVES TUE AFTERNOON FOR VFR CONDITIONS THROUGH THE REST OF THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 413 PM EDT MON JUL 7 2014 WINDS ARE EXPECTED TO BE BELOW 25KTS THROUGH THE PERIOD OUTSIDE OF ANY STRONG SHOWERS OR THUNDERSTORMS. LOW PRESSURE NE OF LAKE SUPERIOR WILL LIFT TOWARD JAMES BAY THIS EVENING AS A WEAK LOW PRESSURE TROUGH MOVES ACROSS LAKE SUPERIOR AND UPPER MI TONIGHT. ANOTHER WEAK LOW PRESSURE TROUGH ACROSS ONTARIO TUESDAY WILL SINK ACROSS LAKE SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY...BEFORE STRONGER HIGH PRESSURE SETTLES ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT THROUGH AT LEAST THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...KF MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
308 PM CDT TUE JUL 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 302 PM CDT TUE JUL 8 2014 LOOKS A QUIET SHORT TERM WITH COOL NORTHWEST FLOW AND BELOW NORMAL TEMPERATURES TONIGHT AND TOMORROW. SCATTERED SHOWERS AND WEAK THUNDERSTORMS OVER WI ARE LOCATED IN AN AREA OF STRONGER COLD ADVECTION AND OUT AHEAD OF A SUBTLE SHORTWAVE FEATURE DROPPING SOUTH ACROSS MN AND WI. THERE IS A SECOND PV ANOMALY IN SD WITH TALLER CUMULUS CLOUDS IN EASTERN SD AND WESTERN MN...BUT THE SHOWER ACTIVITY HAS REMAINED MUCH MORE SPARSE UP TO THIS POINT. VISIBLE SATELLITE ALSO SHOWS A HEALTHY AMOUNT OF SMOKE DROPPING SOUTH ACROSS THE DAKOTAS THIS AFTERNOON...WHICH MIGHT MAKE FOR A COLORFUL SUNSET THIS EVENING...ESPECIALLY FOR THOSE IN WESTERN MN WHO ARE CLOSER TO THE EDGE OF THE SMOKE. THE SMOKE IS BEING ADVECTED SOUTH FROM WILDFIRES IN CANADA...MOST LIKELY FROM WHAT IS BURNING IN THE NORTHWEST TERRITORIES. SATELLITE SHOWED A THICK LAYER OF SMOKE IN ALBERTA AND SASKATCHEWAN AT THIS TIME YESTERDAY. THE ATMOSPHERIC COLUMN CONTINUES TO DRY FROM WHAT WAS PRESENT ON SUNDAY/MONDAY...THE LAST COUPLE MPX SOUNDINGS HAVE SHOWN PWATS OF 1.25" AND 0.90" RESPECTIVELY AND THE EARLY AFTERNOON RAP ANALYSES ARE HOVERING RIGHT AROUND 0.75". THERE IS AN OBVIOUS REDUCTION IN SURFACE MOISTURE TODAY...WITH DEWPOINTS COMFORTABLY IN THE 50S. NOT MUCH ELSE GOING ON IN THE SHORT TERM WITH A SURFACE HIGH SETTLING IN FOR TOMORROW. WITH THE HIGH OVERHEAD...MN/WI WILL BE OUT OF THE BEST PRESSURE GRADIENT AND WILL SEE LIGHTER WINDS TOMORROW. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 302 PM CDT TUE JUL 8 2014 THE MAIN THEME THROUGH THE LATTER PORTION OF THE FORECAST WILL BE A RE-AMPLIFICATION OF THE UPPER AIR PATTERN INTO THAT ALL TOO FAMILIAR CONFIGURATION WE/VE SEEN FOR MUCH OF THE PAST 9 MONTHS. FOR US THAT MEANS AFTER SOME BRIEF MODIFICATION OF TEMPERATURES DURING THE SECOND HALF OF THIS WEEK WE/LL SEE THINGS COOL OFF SUBSTANTIALLY AS WE MOVE TOWARD THE START OF NEXT WEEK. IN THE DETAILS... PCPN CHANCES LOOK TO RETURN FROM WEST TO EAST THURSDAY AND THURSDAY NIGHT AS THE SURFACE HIGH SHIFTS EAST AND WARM ADVECTION COMMENCES OVER THE AREA. IT THEN APPEARS WE/LL NEED TO INCLUDE CHANCE POPS FOR MUCH OF THE TIME FRAME THROUGH AT LEAST SATURDAY AS THE BAROCLINIC ZONE LINGERS IN THE AREA AND WE SEE PERIODIC WEAK DISTURBANCES MOVE THROUGH THE FLOW AND ACROSS OUR AREA. MUCH COOLER TEMPERATURES LOOK TO RETURN BY SUNDAY OR MONDAY AS THE EASTERN TROUGH SIGNIFICANTLY AMPLIFIES. THIS SHOULD BRING DRIER AIR INTO THE REGION AS THE UPPER JET IS DISPLACED SOUTHWARD... ALTHOUGH SUNSHINE DURING THIS TIME OF YEAR COULD CERTAINLY LEAD TO SOME DIURNAL PCPN IF WE HAVE SUFFICIENT CYCLONIC FLOW AND EKMAN PUMPING IN THE BOUNDARY LAYER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1259 PM CDT TUE JUL 8 2014 NO MAJOR AVIATION WEATHER CONCERNS OVER THE NEXT 24-26 HOURS. SCATTERED TO BROKEN CUMULUS CLOUDS WILL DISSIPATE AROUND SUNSET...AS WILL THE WINDS. NO PRECIP IS EXPECTED AND WE HAVE HIGH CONFIDENCE IN VFR AND LITTLE VARIATION IN WIND DIRECTION. SHOWERS WILL GRAZE THE KEAU AIRPORT THIS AIRPORT THIS AFTERNOON...BUT SHOULD ONLY LAST A COUPLE HOURS. KMSP... NO MAJOR AVIATION WEATHER CONCERNS...BUT WE SHOULD KEEP THE BROKEN CUMULUS CLOUDS UNTIL WE BEGIN TO LOSE OUT HEATING LATE THIS AFTERNOON. THEY WILL QUICKLY CLEAR IN THE EARLY EVENING. /OUTLOOK FOR KMSP/ WED...VFR. W-NW WIND LESS THAN 5 KT. THU...VFR. MVFR POSSIBLE IN SHRA/TS LATE. SSE WIND 10 TO 15 KT. FRI...MVFR CONDITIONS POSSIBLE WITH A CHANCE OF SHRA/TSRA. SOUTH WIND 5 TO 10 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...CLF LONG TERM... AVIATION...CLF
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1223 PM CDT TUE JUL 8 2014 .UPDATE... ISSUED AT 1223 PM CDT TUE JUL 8 2014 UPDATED FOR THE 18Z AVIATION DISCUSSION. UPDATE ISSUED AT 914 AM CDT TUE JUL 8 2014 UPDATED TO INCREASE POPS TODAY WITH THE SCATTERED RAIN SHOWERS AND POSSIBLY A FEW ISOLATED WEAK STORMS ACROSS THE REGION IN THE AFTERNOON. NO OTHER SIGNIFICANT CHANGES MADE TO THE SHORT TERM FORECAST AT THIS TIME. && .SYNOPSIS... ISSUED AT 301 AM CDT TUE JUL 8 2014 MID LVL LOW OVER HUDSON BAY EARLY THIS MORNING WITH A FAIRLY LARGE AREA OF CYCLONIC CIRCULATION ASSOCIATED WITH ITS PRESENCE. WITHIN THE CIRCULATION MULTIPLE SHORTWAVE TROFS CONTINUE TO MOVE WITHIN THE FLOW. LATEST WV IMAGERY SHOWS AT LEAST 3 SHORTWAVES EVIDENT ACROSS WRN ONTARIO AND MANITOBA. SCTD SHOWERS CONTINUE TO DEVELOP/OCCUR OVER ERN THIRD OF CWA DESPITE LOSS OF EARLIER INSTABILITY. A WELL DEFINED SHEAR AXIS/WIND SHIFT IS INDICATED IN THE 925 FLOW FROM ERN LAKE COUNTY IN THE ARROWHEAD CURVING THROUGH THE APOSTLES. THIS IS RELATED TO A BACKDOOR FRONTAL BDRY REPRESENTED IN THE LOW LVL THERMAL FIELDS. HEAVY PRECIP...RADAR ESTIMATES AND GROUND REPORT OVER 2 INCHES IN IRON COUNTY...HAS MOVED OUT OF THE CWA. CALLS TO LOCAL LAW OFFICIALS IN THE AREA AND CHECK ON A FEW RIVERS INDICATES THREAT APPEARS TO BE OVER. HAVE LET FLS EXPIRE AT 3AM. && .SHORT TERM...(TODAY THROUGH TOMORROW) ISSUED AT 301 AM CDT TUE JUL 8 2014 TODAY...BACK DOOR FRONTAL BDRY WILL MOVE INTO THE TWIN PORTS EARLY IN THE MORNING AND WEAKEN BY MIDDAY. DISTURBING DIFFERENCES BETWEEN MDLS WITH REGARD TO TIME/HEIGHT XSEC OF MOISTURE WITH EC SUGGESTING WHATEVER LOW CLOUD IS EVIDENT IN MORNING WILL LIFT WITH DAYTIME WARMING. NAM12/RAP SUGGEST A LOW OVERCAST MAY DWELL INTO AFTERNOON AROUND LAKE SUPERIOR. WILL GO PESSIMISTIC IN MORNING AND IMPROVING TREND IN AFTN. PESKY UPPER AIR PATTERN MAKES PLACEMENT OF HIGHEST POPS A BIT CHALLENGING TODAY SO ADDITIONAL UPDATES MAY BE NECESSARY. WITH A LACK OF A LOW LVL FOCUS FOR BDRY LYR CONVERGENCE THE POPS ARE BASED ON A GUESSTIMATE OF THE AXIS OF GREATEST INSTABILITY. USING RUC13 THIS APPEARS TO LINE UP FROM THE IRON RANGE TO NW WISC DURING THE MAJORITY OF THE DIURNAL WARMING. HI RES SIM REFL PRODUCTS SHOW NATURE OF SYNOPTIC PATTERN WITH LARGE INCREASE IN INSTABILITY ECHOES LATE MORNING THROUGH EARLY EVENING OVER MOST OF CWA. SIGNIFICANT DECREASE IN 925 TEMPS COMPARED TO YESTERDAY SO MAX TEMPS WILL BE ABOUT 5 TO 10 DEGREES COOLER IN MANY AREAS. TONIGHT/TOMORROW...MID LVL TROF OVER ONTARIO AND THE GT LAKES WILL SLOWLY SHIFT EAST. LOW LVL CYCLONIC CIRCULATION WILL BE REPLACED BY ANTICYCLONIC FLOW AS A WEAK SFC HIGH MOVES ACROSS UPPER MIDWEST WEDNESDAY. HAVE INSERTED VERY LOW POPS OVER SERN PART OF CWA IN THE AFTN WITH AXIS OF FCST INSTABILITY....ALBEIT MEAGER...IN THE VICINITY. OTHERWISE A PLEASANT DAY WITH NEAR TYPICAL TEMPS. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 301 AM CDT TUE JUL 8 2014 THE AREA OF HIGH PRESSURE WILL CONTINUE TO DOMINATE THE FORECAST AREA THROUGH THURSDAY AFTERNOON. THE TEMPERATURES WILL BE AT OR A LITTLE BELOW THEIR NORMAL VALUES. A WEAK SHORTWAVE WILL MOVE THROUGH CENTRAL MINNESOTA THURSDAY AFTERNOON AND MAY BRING A SHOWER OR THUNDERSTORMS TO SOUTHERN CASS AND CROW WING COUNTIES BUT THESE POPS WILL BE LOW. A COLD FRONT WILL APPROACH THE REGION THURSDAY NIGHT AND MOVE THROUGH THE FORECAST AREA ON FRIDAY AND FRIDAY NIGHT. WITH THE INCREASED MOISTURE AHEAD OF THE FRONT...THERE WILL BE A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS. THE GFS IS FASTER THAN THE ECMWF WITH HIS FEATURE. BOTH MODELS NOW AGREE THAT SATURDAY WILL BE DRY WITH THE BULK OF THE PRECIP SOUTH OF THE FORECAST AREA. THE GFS HAS A FRONT MOVING THROUGH THE REGION ON SUNDAY WITH THE ECMWF A LITTLE SLOWER WITH THE FEATURE. WILL GO WITH A COMPROMISE AT THE MOMENT BUT WILL REFINE AS THE WEEKEND GETS CLOSER. HIGH PRESSURE BUILDS IN FOR THE BEGINNING OF THE WORK WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1223 PM CDT TUE JUL 8 2014 MUCH OF NE MINNESOTA AND NW WISCONSIN HAD VFR CONDITIONS WITH CIGS IN THE 3500 TO 5000 FT RANGE...5 TO 15 KNOT WINDS FROM THE WNW TO NW...AND THERE WERE SHOWERS OVER PARTS OF THE REGION. PARTS OF FAR NORTHERN MINNESOTA HAD LINGERING MVFR CIGS. THERE SHOULD BE A GRADUAL TREND TOWARDS VFR THIS AFTERNOON. THE RAIN SHOWERS WILL CONTINUE...WHICH COULD BRING BRIEF MVFR VSBYS FROM THE RAIN. THE WINDS WILL BEGIN TO DISSIPATE THIS EVENING AND THERE WILL GRADUAL CLEARING OVERNIGHT. && .PRELIMINARY POINT TEMPS/POPS... DLH 70 51 72 52 / 50 20 0 0 INL 69 50 72 50 / 60 20 0 0 BRD 76 53 76 55 / 20 10 0 0 HYR 73 49 74 49 / 60 30 10 0 ASX 63 49 70 49 / 20 20 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ UPDATE...BJT SYNOPSIS...CANNON SHORT TERM...CANNON LONG TERM...STEWART AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
916 AM CDT TUE JUL 8 2014 .UPDATE... ISSUED AT 914 AM CDT TUE JUL 8 2014 UPDATED TO INCREASE POPS TODAY WITH THE SCATTERED RAIN SHOWERS AND POSSIBLY A FEW ISOLATED WEAK STORMS ACROSS THE REGION IN THE AFTERNOON. NO OTHER SIGNIFICANT CHANGES MADE TO THE SHORT TERM FORECAST AT THIS TIME. && .SYNOPSIS... ISSUED AT 301 AM CDT TUE JUL 8 2014 MID LVL LOW OVER HUDSON BAY EARLY THIS MORNING WITH A FAIRLY LARGE AREA OF CYCLONIC CIRCULATION ASSOCIATED WITH ITS PRESENCE. WITHIN THE CIRCULATION MULTIPLE SHORTWAVE TROFS CONTINUE TO MOVE WITHIN THE FLOW. LATEST WV IMAGERY SHOWS AT LEAST 3 SHORTWAVES EVIDENT ACROSS WRN ONTARIO AND MANITOBA. SCTD SHOWERS CONTINUE TO DEVELOP/OCCUR OVER ERN THIRD OF CWA DESPITE LOSS OF EARLIER INSTABILITY. A WELL DEFINED SHEAR AXIS/WIND SHIFT IS INDICATED IN THE 925 FLOW FROM ERN LAKE COUNTY IN THE ARROWHEAD CURVING THROUGH THE APOSTLES. THIS IS RELATED TO A BACKDOOR FRONTAL BDRY REPRESENTED IN THE LOW LVL THERMAL FIELDS. HEAVY PRECIP...RADAR ESTIMATES AND GROUND REPORT OVER 2 INCHES IN IRON COUNTY...HAS MOVED OUT OF THE CWA. CALLS TO LOCAL LAW OFFICIALS IN THE AREA AND CHECK ON A FEW RIVERS INDICATES THREAT APPEARS TO BE OVER. HAVE LET FLS EXPIRE AT 3AM. && .SHORT TERM...(TODAY THROUGH TOMORROW) ISSUED AT 301 AM CDT TUE JUL 8 2014 TODAY...BACK DOOR FRONTAL BDRY WILL MOVE INTO THE TWIN PORTS EARLY IN THE MORNING AND WEAKEN BY MIDDAY. DISTURBING DIFFERENCES BETWEEN MDLS WITH REGARD TO TIME/HEIGHT XSEC OF MOISTURE WITH EC SUGGESTING WHATEVER LOW CLOUD IS EVIDENT IN MORNING WILL LIFT WITH DAYTIME WARMING. NAM12/RAP SUGGEST A LOW OVERCAST MAY DWELL INTO AFTERNOON AROUND LAKE SUPERIOR. WILL GO PESSIMISTIC IN MORNING AND IMPROVING TREND IN AFTN. PESKY UPPER AIR PATTERN MAKES PLACEMENT OF HIGHEST POPS A BIT CHALLENGING TODAY SO ADDITIONAL UPDATES MAY BE NECESSARY. WITH A LACK OF A LOW LVL FOCUS FOR BDRY LYR CONVERGENCE THE POPS ARE BASED ON A GUESSTIMATE OF THE AXIS OF GREATEST INSTABILITY. USING RUC13 THIS APPEARS TO LINE UP FROM THE IRON RANGE TO NW WISC DURING THE MAJORITY OF THE DIURNAL WARMING. HI RES SIM REFL PRODUCTS SHOW NATURE OF SYNOPTIC PATTERN WITH LARGE INCREASE IN INSTABILITY ECHOES LATE MORNING THROUGH EARLY EVENING OVER MOST OF CWA. SIGNIFICANT DECREASE IN 925 TEMPS COMPARED TO YESTERDAY SO MAX TEMPS WILL BE ABOUT 5 TO 10 DEGREES COOLER IN MANY AREAS. TONIGHT/TOMORROW...MID LVL TROF OVER ONTARIO AND THE GT LAKES WILL SLOWLY SHIFT EAST. LOW LVL CYCLONIC CIRCULATION WILL BE REPLACED BY ANTICYCLONIC FLOW AS A WEAK SFC HIGH MOVES ACROSS UPPER MIDWEST WEDNESDAY. HAVE INSERTED VERY LOW POPS OVER SERN PART OF CWA IN THE AFTN WITH AXIS OF FCST INSTABILITY....ALBEIT MEAGER...IN THE VICINITY. OTHERWISE A PLEASANT DAY WITH NEAR TYPICAL TEMPS. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 301 AM CDT TUE JUL 8 2014 THE AREA OF HIGH PRESSURE WILL CONTINUE TO DOMINATE THE FORECAST AREA THROUGH THURSDAY AFTERNOON. THE TEMPERATURES WILL BE AT OR A LITTLE BELOW THEIR NORMAL VALUES. A WEAK SHORTWAVE WILL MOVE THROUGH CENTRAL MINNESOTA THURSDAY AFTERNOON AND MAY BRING A SHOWER OR THUNDERSTORMS TO SOUTHERN CASS AND CROW WING COUNTIES BUT THESE POPS WILL BE LOW. A COLD FRONT WILL APPROACH THE REGION THURSDAY NIGHT AND MOVE THROUGH THE FORECAST AREA ON FRIDAY AND FRIDAY NIGHT. WITH THE INCREASED MOISTURE AHEAD OF THE FRONT...THERE WILL BE A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS. THE GFS IS FASTER THAN THE ECMWF WITH HIS FEATURE. BOTH MODELS NOW AGREE THAT SATURDAY WILL BE DRY WITH THE BULK OF THE PRECIP SOUTH OF THE FORECAST AREA. THE GFS HAS A FRONT MOVING THROUGH THE REGION ON SUNDAY WITH THE ECMWF A LITTLE SLOWER WITH THE FEATURE. WILL GO WITH A COMPROMISE AT THE MOMENT BUT WILL REFINE AS THE WEEKEND GETS CLOSER. HIGH PRESSURE BUILDS IN FOR THE BEGINNING OF THE WORK WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 645 AM CDT TUE JUL 8 2014 MAINLY MVFR/IFR CIGS ACROSS TAF SITES EXCEPT FOR BRD WHERE VFR CONDITIONS ARE DOMINANT. CONDITIONS SHOULD IMPROVE TO VFR AT ALL SITES BY LATE MORNING. BUT...MVFR CONDITIONS ARE POSSIBLE THIS AFTERNOON WITH SHOWERS AND ISOLATED THUNDERSTORMS DUE TO SOLAR HEATING. CONDITIONS WILL IMPROVE TO VFR AFTER SUNSET AS AN AREA OF HIGH PRESSURE BUILDS INTO THE FORECAST AREA. && .PRELIMINARY POINT TEMPS/POPS... DLH 66 50 72 52 / 50 20 0 0 INL 66 48 72 50 / 60 20 0 0 BRD 75 52 76 55 / 20 10 0 0 HYR 70 49 74 49 / 60 30 10 0 ASX 63 48 70 49 / 20 20 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ UPDATE...BJT SYNOPSIS...CANNON SHORT TERM...CANNON LONG TERM...STEWART AVIATION...STEWART
AREA FORECAST DISCUSSION
NWS DULUTH MN
644 AM CDT TUE JUL 8 2014 .SYNOPSIS... ISSUED AT 301 AM CDT TUE JUL 8 2014 MID LVL LOW OVER HUDSON BAY EARLY THIS MORNING WITH A FAIRLY LARGE AREA OF CYCLONIC CIRCULATION ASSOCIATED WITH ITS PRESENCE. WITHIN THE CIRCULATION MULTIPLE SHORTWAVE TROFS CONTINUE TO MOVE WITHIN THE FLOW. LATEST WV IMAGERY SHOWS AT LEAST 3 SHORTWAVES EVIDENT ACROSS WRN ONTARIO AND MANITOBA. SCTD SHOWERS CONTINUE TO DEVELOP/OCCUR OVER ERN THIRD OF CWA DESPITE LOSS OF EARLIER INSTABILITY. A WELL DEFINED SHEAR AXIS/WIND SHIFT IS INDICATED IN THE 925 FLOW FROM ERN LAKE COUNTY IN THE ARROWHEAD CURVING THROUGH THE APOSTLES. THIS IS RELATED TO A BACKDOOR FRONTAL BDRY REPRESENTED IN THE LOW LVL THERMAL FIELDS. HEAVY PRECIP...RADAR ESTIMATES AND GROUND REPORT OVER 2 INCHES IN IRON COUNTY...HAS MOVED OUT OF THE CWA. CALLS TO LOCAL LAW OFFICIALS IN THE AREA AND CHECK ON A FEW RIVERS INDICATES THREAT APPEARS TO BE OVER. HAVE LET FLS EXPIRE AT 3AM. && .SHORT TERM...(TODAY THROUGH TOMORROW) ISSUED AT 301 AM CDT TUE JUL 8 2014 TODAY...BACK DOOR FRONTAL BDRY WILL MOVE INTO THE TWIN PORTS EARLY IN THE MORNING AND WEAKEN BY MIDDAY. DISTURBING DIFFERENCES BETWEEN MDLS WITH REGARD TO TIME/HEIGHT XSEC OF MOISTURE WITH EC SUGGESTING WHATEVER LOW CLOUD IS EVIDENT IN MORNING WILL LIFT WITH DAYTIME WARMING. NAM12/RAP SUGGEST A LOW OVERCAST MAY DWELL INTO AFTERNOON AROUND LAKE SUPERIOR. WILL GO PESSIMISTIC IN MORNING AND IMPROVING TREND IN AFTN. PESKY UPPER AIR PATTERN MAKES PLACEMENT OF HIGHEST POPS A BIT CHALLENGING TODAY SO ADDITIONAL UPDATES MAY BE NECESSARY. WITH A LACK OF A LOW LVL FOCUS FOR BDRY LYR CONVERGENCE THE POPS ARE BASED ON A GUESSTIMATE OF THE AXIS OF GREATEST INSTABILITY. USING RUC13 THIS APPEARS TO LINE UP FROM THE IRON RANGE TO NW WISC DURING THE MAJORITY OF THE DIURNAL WARMING. HI RES SIM REFL PRODUCTS SHOW NATURE OF SYNOPTIC PATTERN WITH LARGE INCREASE IN INSTABILITY ECHOES LATE MORNING THROUGH EARLY EVENING OVER MOST OF CWA. SIGNIFICANT DECREASE IN 925 TEMPS COMPARED TO YESTERDAY SO MAX TEMPS WILL BE ABOUT 5 TO 10 DEGREES COOLER IN MANY AREAS. TONIGHT/TOMORROW...MID LVL TROF OVER ONTARIO AND THE GT LAKES WILL SLOWLY SHIFT EAST. LOW LVL CYCLONIC CIRCULATION WILL BE REPLACED BY ANTICYCLONIC FLOW AS A WEAK SFC HIGH MOVES ACROSS UPPER MIDWEST WEDNESDAY. HAVE INSERTED VERY LOW POPS OVER SERN PART OF CWA IN THE AFTN WITH AXIS OF FCST INSTABILITY....ALBEIT MEAGER...IN THE VICINITY. OTHERWISE A PLEASANT DAY WITH NEAR TYPICAL TEMPS. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 301 AM CDT TUE JUL 8 2014 THE AREA OF HIGH PRESSURE WILL CONTINUE TO DOMINATE THE FORECAST AREA THROUGH THURSDAY AFTERNOON. THE TEMPERATURES WILL BE AT OR A LITTLE BELOW THEIR NORMAL VALUES. A WEAK SHORTWAVE WILL MOVE THROUGH CENTRAL MINNESOTA THURSDAY AFTERNOON AND MAY BRING A SHOWER OR THUNDERSTORMS TO SOUTHERN CASS AND CROW WING COUNTIES BUT THESE POPS WILL BE LOW. A COLD FRONT WILL APPROACH THE REGION THURSDAY NIGHT AND MOVE THROUGH THE FORECAST AREA ON FRIDAY AND FRIDAY NIGHT. WITH THE INCREASED MOISTURE AHEAD OF THE FRONT...THERE WILL BE A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS. THE GFS IS FASTER THAN THE ECMWF WITH HIS FEATURE. BOTH MODELS NOW AGREE THAT SATURDAY WILL BE DRY WITH THE BULK OF THE PRECIP SOUTH OF THE FORECAST AREA. THE GFS HAS A FRONT MOVING THROUGH THE REGION ON SUNDAY WITH THE ECMWF A LITTLE SLOWER WITH THE FEATURE. WILL GO WITH A COMPROMISE AT THE MOMENT BUT WILL REFINE AS THE WEEKEND GETS CLOSER. HIGH PRESSURE BUILDS IN FOR THE BEGINNING OF THE WORK WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 645 AM CDT TUE JUL 8 2014 MAINLY MVFR/IFR CIGS ACROSS TAF SITES EXCEPT FOR BRD WHERE VFR CONDTIONS ARE DOMINANT. CONDITIONS SHOULD IMPROVE TO VFR AT ALL SITES BY LATE MORNING. BUT...MVFR CONDITIONS ARE POSSIBLE THIS AFTERNOON WITH SHOWERS AND ISOLATED THUNDERSTORMS DUE TO SOLAR HEATING. CONDTIONS WILL IMPROVE TO VFR AFTER SUNSET AS AN AREA OF HIGH PRESSURE BUILDS INTO THE FORECAST AREA. && .PRELIMINARY POINT TEMPS/POPS... DLH 69 51 72 52 / 40 20 0 0 INL 67 48 72 50 / 40 20 0 0 BRD 74 53 76 55 / 20 10 0 0 HYR 71 49 74 49 / 50 20 10 0 ASX 66 49 70 49 / 40 30 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ SYNOPSIS...CANNON SHORT TERM...CANNON LONG TERM...STEWART AVIATION...STEWART
AREA FORECAST DISCUSSION
NWS DULUTH MN
342 AM CDT TUE JUL 8 2014 .SYNOPSIS... ISSUED AT 301 AM CDT TUE JUL 8 2014 MID LVL LOW OVER HUDSON BAY EARLY THIS MORNING WITH A FAIRLY LARGE AREA OF CYCLONIC CIRCULATION ASSOCIATED WITH ITS PRESENCE. WITHIN THE CIRCULATION MULTIPLE SHORTWAVE TROFS CONTINUE TO MOVE WITHIN THE FLOW. LATEST WV IMAGERY SHOWS AT LEAST 3 SHORTWAVES EVIDENT ACROSS WRN ONTARIO AND MANITOBA. SCTD SHOWERS CONTINUE TO DEVELOP/OCCUR OVER ERN THIRD OF CWA DESPITE LOSS OF EARLIER INSTABILITY. A WELL DEFINED SHEAR AXIS/WIND SHIFT IS INDICATED IN THE 925 FLOW FROM ERN LAKE COUNTY IN THE ARROWHEAD CURVING THROUGH THE APOSTLES. THIS IS RELATED TO A BACKDOOR FRONTAL BDRY REPRESENTED IN THE LOW LVL THERMAL FIELDS. HEAVY PRECIP...RADAR ESTIMATES AND GROUND REPORT OVER 2 INCHES IN IRON COUNTY...HAS MOVED OUT OF THE CWA. CALLS TO LOCAL LAW OFFICIALS IN THE AREA AND CHECK ON A FEW RIVERS INDICATES THREAT APPEARS TO BE OVER. HAVE LET FLS EXPIRE AT 3AM. && .SHORT TERM...(TODAY THROUGH TOMORROW) ISSUED AT 301 AM CDT TUE JUL 8 2014 TODAY...BACK DOOR FRONTAL BDRY WILL MOVE INTO THE TWIN PORTS EARLY IN THE MORNING AND WEAKEN BY MIDDAY. DISTURBING DIFFERENCES BETWEEN MDLS WITH REGARD TO TIME/HEIGHT XSEC OF MOISTURE WITH EC SUGGESTING WHATEVER LOW CLOUD IS EVIDENT IN MORNING WILL LIFT WITH DAYTIME WARMING. NAM12/RAP SUGGEST A LOW OVERCAST MAY DWELL INTO AFTERNOON AROUND LAKE SUPERIOR. WILL GO PESSIMISTIC IN MORNING AND IMPROVING TREND IN AFTN. PESKY UPPER AIR PATTERN MAKES PLACEMENT OF HIGHEST POPS A BIT CHALLENGING TODAY SO ADDITIONAL UPDATES MAY BE NECESSARY. WITH A LACK OF A LOW LVL FOCUS FOR BDRY LYR CONVERGENCE THE POPS ARE BASED ON A GUESSTIMATE OF THE AXIS OF GREATEST INSTABILITY. USING RUC13 THIS APPEARS TO LINE UP FROM THE IRON RANGE TO NW WISC DURING THE MAJORITY OF THE DIURNAL WARMING. HI RES SIM REFL PRODUCTS SHOW NATURE OF SYNOPTIC PATTERN WITH LARGE INCREASE IN INSTABILITY ECHOES LATE MORNING THROUGH EARLY EVENING OVER MOST OF CWA. SIGNIFICANT DECREASE IN 925 TEMPS COMPARED TO YESTERDAY SO MAX TEMPS WILL BE ABOUT 5 TO 10 DEGREES COOLER IN MANY AREAS. TONIGHT/TOMORROW...MID LVL TROF OVER ONTARIO AND THE GT LAKES WILL SLOWLY SHIFT EAST. LOW LVL CYCLONIC CIRCULATION WILL BE REPLACED BY ANTICYCLONIC FLOW AS A WEAK SFC HIGH MOVES ACROSS UPPER MIDWEST WEDNESDAY. HAVE INSERTED VERY LOW POPS OVER SERN PART OF CWA IN THE AFTN WITH AXIS OF FCST INSTABILITY....ALBEIT MEAGER...IN THE VICINITY. OTHERWISE A PLEASANT DAY WITH NEAR TYPICAL TEMPS. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 301 AM CDT TUE JUL 8 2014 THE AREA OF HIGH PRESSURE WILL CONTINUE TO DOMINATE THE FORECAST AREA THROUGH THURSDAY AFTERNOON. THE TEMPERATURES WILL BE AT OR A LITTLE BELOW THEIR NORMAL VALUES. A WEAK SHORTWAVE WILL MOVE THROUGH CENTRAL MINNESOTA THURSDAY AFTERNOON AND MAY BRING A SHOWER OR THUNDERSTORMS TO SOUTHERN CASS AND CROW WING COUNTIES BUT THESE POPS WILL BE LOW. A COLD FRONT WILL APPROACH THE REGION THURSDAY NIGHT AND MOVE THROUGH THE FORECAST AREA ON FRIDAY AND FRIDAY NIGHT. WITH THE INCREASED MOISTURE AHEAD OF THE FRONT...THERE WILL BE A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS. THE GFS IS FASTER THAN THE ECMWF WITH HIS FEATURE. BOTH MODELS NOW AGREE THAT SATURDAY WILL BE DRY WITH THE BULK OF THE PRECIP SOUTH OF THE FORECAST AREA. THE GFS HAS A FRONT MOVING THROUGH THE REGION ON SUNDAY WITH THE ECMWF A LITTLE SLOWER WITH THE FEATURE. WILL GO WITH A COMPROMISE AT THE MOMENT BUT WILL REFINE AS THE WEEKEND GETS CLOSER. HIGH PRESSURE BUILDS IN FOR THE BEGINNING OF THE WORK WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 709 PM CDT MON JUL 7 2014 SCATTERED STRONG THUNDERSTORMS WILL CONTINUE TO BE FOUND ACROSS THE NORTHLAND OVERNIGHT...BUT THE TREND WILL BE TOWARD MORE SHOWER ACTIVITY AS THE NIGHT WEARS ON. VFR CONDITIONS WILL BE THE RULE...BUT OCCASIONALLY THERE WILL BE SOME MVFR/IFR CIGS/VSBYS DUE TO THE STRONGER SHOWERS AND THUNDERSTORMS. && .PRELIMINARY POINT TEMPS/POPS... DLH 69 51 72 52 / 40 20 0 0 INL 67 48 72 50 / 40 20 0 0 BRD 74 53 76 55 / 20 10 0 0 HYR 71 49 74 49 / 50 20 10 0 ASX 66 49 70 49 / 40 30 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ SYNOPSIS...CANNON SHORT TERM...CANNON LONG TERM...STEWART AVIATION...DAP
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1231 PM CDT Tue Jul 8 2014 .UPDATE: Issued at 734 AM CDT Tue Jul 8 2014 Showers and isolated thunderstorms associated with decaying MCS have rapidly diminished early this morning, and based on latest regional radar trends primary threat will be confined to far southern sections of the FA over the next few hours. No changes to the afternoon trends at this time, with primary threat of redevelopment south of a Steelville-KCPS-Vandalia IL line. Zone update out shortly. Truett && .SHORT TERM: (Through Late This Afternoon) Issued at 353 AM CDT Tue Jul 8 2014 The weakening MCS moving southeastward through east central and southeast MO as well as southwest IL should shift southeast of our forecast area later this morning. The cold front now across northwest MO will move southeastward through the forecast area today. Although we could not rule out redevelopment of convection this afternoon along and just ahead of this cold front, it appears that the effective low level boundary will be the outflow from this mornings MCS which will be southeast of our forecast area this afternoon. The latest HRRR develops convection late this afternoon south and southeast of the forecast area. Even the operational models afternoon qpf is confined to the extreme southern or southeastern portion of our forecast area. For now will include chance pops across southeast MO and southwest IL, south and east of STL for this afternoon. High temperatures today will be slightly cooler than yesterday due to at least weak cold air advection behind the cold front and gradually lowering 850 mb temperatures. GKS .LONG TERM: (Tonight through Monday) Issued at 445 AM CDT Tue Jul 8 2014 It appears that the showers/storms will be south or southeast of our forecast area by this evening as a surface ridge builds southeastward into our area behind the cold front. This will bring cooler and less humid air into the region tonight and Wednesday. Will have at least slightly below normal temperatures for tonight through Wednesday night. The next chance of convection will occur over the northern portion of our forecast area late Thursday night and Friday morning due to strong low level warm air advection and moisture convergence on the nose of a southwesterly low level jet ahead of a northwest flow shortwave. The models were also depicting relatively strong upper level divergence ahead of this shortwave. A warming trend will also begin Thursday night and Friday along with increasing humidities due to southerly return flow on the backside of the surface ridge as it shifts east of the region. An upper level ridge will try to build northeastward into southwestern MO Friday night and Saturday. Any potential for convection should be confined to the northern and eastern portion of the forecast area as shortwaves move east southeastward over the upper level ridge. Temperatures should be quite warm this weekend, especially across central and southeast MO. There will be the chance of showers/storms across the entire area as we head into the next work week as the models deepen an upper level trough over the Great Lakes region and send a cold front southeastward through our forecast area Sunday night and Monday. The ECMWF model is stronger or deeper with this upper level trough compared to the GFS model and is also slower moving the front through our forecast area and has more qpf associated with this front. Due to the model inconsistencies will just include chance pops for most of the area on Monday along with cooler high temperatures. GKS && .AVIATION: (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1220 PM CDT Tue Jul 8 2014 Current cigs will break up and become sct this afternoon. Expect the remainder of the TAF period to be VFR. Winds will diminish and back slightly this evening and become nwly again Wed morning. Only expect diurnal CU Wed morning. Some guidance is suggesting that FG may develop and impact UIN/COU late tonight. While the rainfall last night may support this, believe enuf mixing will persist tonight to prevent FG development. Specifics for KSTL: VFR and dry conditions are expected thru the period. Cigs are expected to quickly break up this afternoon with winds remaining nwly this afternoon. Winds will diminish and back slightly this evening and become nwly again Wed morning. Only sct diurnal CU is expected Wed. Tilly && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
739 AM CDT Tue Jul 8 2014 .UPDATE: Issued at 734 AM CDT Tue Jul 8 2014 Showers and isolated thunderstorms associated with decaying MCS have rapidly diminished early this morning, and based on latest regional radar trends primary threat will be confined to far southern sections of the FA over the next few hours. No changes to the afternoon trends at this time, with primary threat of redevelopment south of a Steelville-KCPS-Vandalia IL line. Zone update out shortly. Truett && .SHORT TERM: (Through Late This Afternoon) Issued at 353 AM CDT Tue Jul 8 2014 The weakening MCS moving southeastward through east central and southeast MO as well as southwest IL should shift southeast of our forecast area later this morning. The cold front now across northwest MO will move southeastward through the forecast area today. Although we could not rule out redevelopment of convection this afternoon along and just ahead of this cold front, it appears that the effective low level boundary will be the outflow from this mornings MCS which will be southeast of our forecast area this afternoon. The latest HRRR develops convection late this afternoon south and southeast of the forecast area. Even the operational models afternoon qpf is confined to the extreme southern or southeastern portion of our forecast area. For now will include chance pops across southeast MO and southwest IL, south and east of STL for this afternoon. High temperatures today will be slightly cooler than yesterday due to at least weak cold air advection behind the cold front and gradually lowering 850 mb temperatures. GKS .LONG TERM: (Tonight through Monday) Issued at 445 AM CDT Tue Jul 8 2014 It appears that the showers/storms will be south or southeast of our forecast area by this evening as a surface ridge builds southeastward into our area behind the cold front. This will bring cooler and less humid air into the region tonight and Wednesday. Will have at least slightly below normal temperatures for tonight through Wednesday night. The next chance of convection will occur over the northern portion of our forecast area late Thursday night and Friday morning due to strong low level warm air advection and moisture convergence on the nose of a southwesterly low level jet ahead of a northwest flow shortwave. The models were also depicting relatively strong upper level divergence ahead of this shortwave. A warming trend will also begin Thursday night and Friday along with increasing humidities due to southerly return flow on the backside of the surface ridge as it shifts east of the region. An upper level ridge will try to build northeastward into southwestern MO Friday night and Saturday. Any potential for convection should be confined to the northern and eastern portion of the forecast area as shortwaves move east southeastward over the upper level ridge. Temperatures should be quite warm this weekend, especially across central and southeast MO. There will be the chance of showers/storms across the entire area as we head into the next work week as the models deepen an upper level trough over the Great Lakes region and send a cold front southeastward through our forecast area Sunday night and Monday. The ECMWF model is stronger or deeper with this upper level trough compared to the GFS model and is also slower moving the front through our forecast area and has more qpf associated with this front. Due to the model inconsistencies will just include chance pops for most of the area on Monday along with cooler high temperatures. GKS && .AVIATION: (For the 12z TAFs through 12z Wednesday Morning) Issued at 633 AM CDT Tue Jul 8 2014 Surface obs have been indicating some very patchy stratus at several locations just before daybreak, so have also mentioned this at most locations as few or scattered deck between 1-2kft for the next 1-2 hours. Soundings then suggest a scattered CU field developing by mid morning with bases aoa 3kft, with these diurnally driven clouds then dissipate by early this evening. Consensus of all of the guidance suggests that any development that does develop this afternoon will be well south of our TAF sites, so forecast remains dry. Specifics for KSTL: Other than a bit of stratus with bases 1-2kft over the next hour or so, expecting scattered clouds with bases aoa 3kft from mid-morning into the afternoon with west-northwest winds in the 10-15 kt range. Clouds will dissipate and early this evening with loss of heating, with winds diminishing to less than 7 kts. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
646 AM CDT Tue Jul 8 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 353 AM CDT Tue Jul 8 2014 The weakening MCS moving southeastward through east central and southeast MO as well as southwest IL should shift southeast of our forecast area later this morning. The cold front now across northwest MO will move southeastward through the forecast area today. Although we could not rule out redevelopment of convection this afternoon along and just ahead of this cold front, it appears that the effective low level boundary will be the outflow from this mornings MCS which will be southeast of our forecast area this afternoon. The latest HRRR develops convection late this afternoon south and southeast of the forecast area. Even the operational models afternoon qpf is confined to the extreme southern or southeastern portion of our forecast area. For now will include chance pops across southeast MO and southwest IL, south and east of STL for this afternoon. High temperatures today will be slightly cooler than yesterday due to at least weak cold air advection behind the cold front and gradually lowering 850 mb temperatures. GKS .LONG TERM: (Tonight through Monday) Issued at 445 AM CDT Tue Jul 8 2014 It appears that the showers/storms will be south or southeast of our forecast area by this evening as a surface ridge builds southeastward into our area behind the cold front. This will bring cooler and less humid air into the region tonight and Wednesday. Will have at least slightly below normal temperatures for tonight through Wednesday night. The next chance of convection will occur over the northern portion of our forecast area late Thursday night and Friday morning due to strong low level warm air advection and moisture convergence on the nose of a southwesterly low level jet ahead of a northwest flow shortwave. The models were also depicting relatively strong upper level divergence ahead of this shortwave. A warming trend will also begin Thursday night and Friday along with increasing humidities due to southerly return flow on the backside of the surface ridge as it shifts east of the region. An upper level ridge will try to build northeastward into southwestern MO Friday night and Saturday. Any potential for convection should be confined to the northern and eastern portion of the forecast area as shortwaves move east southeastward over the upper level ridge. Temperatures should be quite warm this weekend, especially across central and southeast MO. There will be the chance of showers/storms across the entire area as we head into the next work week as the models deepen an upper level trough over the Great Lakes region and send a cold front southeastward through our forecast area Sunday night and Monday. The ECMWF model is stronger or deeper with this upper level trough compared to the GFS model and is also slower moving the front through our forecast area and has more qpf associated with this front. Due to the model inconsistencies will just include chance pops for most of the area on Monday along with cooler high temperatures. GKS && .AVIATION: (For the 12z TAFs through 12z Wednesday Morning) Issued at 633 AM CDT Tue Jul 8 2014 Surface obs have been indicating some very patchy stratus at several locations just before daybreak, so have also mentioned this at most locations as few or scattered deck between 1-2kft for the next 1-2 hours. Soundings then suggest a scattered CU field developing by mid morning with bases aoa 3kft, with these diurnally driven clouds then dissipate by early this evening. Consensus of all of the guidance suggests that any development that does develop this afternoon will be well south of our TAF sites, so forecast remains dry. Specifics for KSTL: Other than a bit of stratus with bases 1-2kft over the next hour or so, expecting scattered clouds with bases aoa 3kft from mid-morning into the afternoon with west-northwest winds in the 10-15 kt range. Clouds will dissipate and early this evening with loss of heating, with winds diminishing to less than 7 kts. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
445 AM CDT Tue Jul 8 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 353 AM CDT Tue Jul 8 2014 The weakening MCS moving southeastward through east central and southeast MO as well as southwest IL should shift southeast of our forecast area later this morning. The cold front now across northwest MO will move southeastward through the forecast area today. Although we could not rule out redevelopment of convection this afternoon along and just ahead of this cold front, it appears that the effective low level boundary will be the outflow from this mornings MCS which will be southeast of our forecast area this afternoon. The latest HRRR develops convection late this afternoon south and southeast of the forecast area. Even the operational models afternoon qpf is confined to the extreme southern or southeastern portion of our forecast area. For now will include chance pops across southeast MO and southwest IL, south and east of STL for this afternoon. High temperatures today will be slightly cooler than yesterday due to at least weak cold air advection behind the cold front and gradually lowering 850 mb temperatures. GKS .LONG TERM: (Tonight through Monday) Issued at 445 AM CDT Tue Jul 8 2014 It appears that the showers/storms will be south or southeast of our forecast area by this evening as a surface ridge builds southeastward into our area behind the cold front. This will bring cooler and less humid air into the region tonight and Wednesday. Will have at least slightly below normal temperatures for tonight through Wednesday night. The next chance of convection will occur over the northern portion of our forecast area late Thursday night and Friday morning due to strong low level warm air advection and moisture convergence on the nose of a southwesterly low level jet ahead of a northwest flow shortwave. The models were also depicting relatively strong upper level divergence ahead of this shortwave. A warming trend will also begin Thursday night and Friday along with increasing humidities due to southerly return flow on the backside of the surface ridge as it shifts east of the region. An upper level ridge will try to build northeastward into southwestern MO Friday night and Saturday. Any potential for convection should be confined to the northern and eastern portion of the forecast area as shortwaves move east southeastward over the upper level ridge. Temperatures should be quite warm this weekend, especially across central and southeast MO. There will be the chance of showers/storms across the entire area as we head into the next work week as the models deepen an upper level trough over the Great Lakes region and send a cold front southeastward through our forecast area Sunday night and Monday. The ECMWF model is stronger or deeper with this upper level trough compared to the GFS model and is also slower moving the front through our forecast area and has more qpf associated with this front. Due to the model inconsistencies will just include chance pops for most of the area on Monday along with cooler high temperatures. GKS && .AVIATION: (For the 06z TAFs through 06z Tuesday Night) Issued at 1241 AM CDT Tue Jul 8 2014 Squall line is marching east-southeast through the area with a large area of stratoform rain behind it. Primary concern will be wind gusts in excess of 50kts as the line moves through, and second brief IFR flight conditions in heavy rain. CIGs/VSBYs improve pretty rapidly to high end MVFR and VFR behind the line in the lighter rain. Expect this light rain and thunder to continue for several hours behind the line. Flight conditions may briefly dip into MVFR in this area, but believe VFR flight conditions will prevail. Expect rain to end from northwest to southeast across the area through 12Z Tuesday morning. Specifics for KSTL: Squall line is marching east-southeast through the area with a large area of stratoform rain behind it. Primary concern will be wind gusts in excess of 50kts as the line moves through, and second brief IFR flight conditions in heavy rain. CIGs/VSBYs improve pretty rapidly to high end MVFR and VFR behind the line in the lighter rain. Expect this light rain and thunder to continue for several hours behind the line. Flight conditions may briefly dip into MVFR in this area, but believe VFR flight conditions will prevail. Expect rain to end from northwest to southeast...probably ending between 10-12Z at Lambert. Carney && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
354 AM CDT Tue Jul 8 2014 .SHORT TERM: (Through Late This Afternoon) Issued at 353 AM CDT Tue Jul 8 2014 The weakening MCS moving southeastward through east central and southeast MO as well as southwest IL should shift southeast of our forecast area later this morning. The cold front now across northwest MO will move southeastward through the forecast area today. Although we could not rule out redevelopment of convection this afternoon along and just ahead of this cold front, it appears that the effective low level boundary will be the outflow from this mornings MCS which will be southeast of our forecast area this afternoon. The latest HRRR develops convection late this afternoon south and southeast of the forecast area. Even the operational models afternoon qpf is confined to the extreme southern or southeastern portion of our forecast area. For now will include chance pops across southeast MO and southwest IL, south and east of STL for this afternoon. High temperatures today will be slightly cooler than yesterday due to at least weak cold air advection behind the cold front and gradually lowering 850 mb temperatures. GKS .LONG TERM: (Tuesday through Next Monday) Issued at 341 PM CDT Mon Jul 7 2014 (Tuesday through Thursday) On Tuesday, the front will be moving south and out of the CWA about the time that thunderstorms will be initiating during the early-mid afternoon hours. There is still some potential that one or two of these storms could become severe before they move out of the CWA during the late afternoon hours. The front will then move well south of the area Wednesday into Thursday as the flow becomes northwesterly aloft. The area will lie under mainly subsidence during this period, so have kept these two days dry. 850 mb temperatures will be between 12-18C promising below normal temperatures. (Friday through next Monday) Warm front is still on track to move through the area on Friday and Saturday causing temperatures to climb back closer to normal. The front will keep scattered thunderstorms in the forecast. 850 mb temperatures of 18-20C call for temperatures at or just above normal. ECMWF sets up northwesterly flow over the area quicker than the GFS on Saturday and Sunday, so consequently it is trying to bring a cold front through the CWA faster. This solution is faster than in previous runs, so went with the slower idea with a cold front entering the northern part of the CWA on Sunday morning and move it south across the area through Monday. Will continue the chance of thunderstorms into early next week. Britt && .AVIATION: (For the 06z TAFs through 06z Tuesday Night) Issued at 1241 AM CDT Tue Jul 8 2014 Squall line is marching east-southeast through the area with a large area of stratoform rain behind it. Primary concern will be wind gusts in excess of 50kts as the line moves through, and second brief IFR flight conditions in heavy rain. CIGs/VSBYs improve pretty rapidly to high end MVFR and VFR behind the line in the lighter rain. Expect this light rain and thunder to continue for several hours behind the line. Flight conditions may briefly dip into MVFR in this area, but believe VFR flight conditions will prevail. Expect rain to end from northwest to southeast across the area through 12Z Tuesday morning. Specifics for KSTL: Squall line is marching east-southeast through the area with a large area of stratoform rain behind it. Primary concern will be wind gusts in excess of 50kts as the line moves through, and second brief IFR flight conditions in heavy rain. CIGs/VSBYs improve pretty rapidly to high end MVFR and VFR behind the line in the lighter rain. Expect this light rain and thunder to continue for several hours behind the line. Flight conditions may briefly dip into MVFR in this area, but believe VFR flight conditions will prevail. Expect rain to end from northwest to southeast...probably ending between 10-12Z at Lambert. Carney && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
900 PM MDT Wed Jul 9 2014 .DISCUSSION... Update forthcoming. Satellite imagery shows moisture continuing to be advected over southwest Montana this evening where the airmass remains somewhat unstable. The resulting showers and isolated thunderstorms will persist through 06z, mainly south of a KDLN-KBZN line. Latest RUC run, as well as HRRR analysis, indicate convective activity will shift to the east after 06z and decrease in areal coverage and intensity. North of the KDLN-KBZN line the airmass is much more stable and no precipitation is expected overnight. Temperatures look on track. && .AVIATION... UPDATED 0105Z. VFR conditions are expected to continue across the area at least through Thursday. A disturbance over the Pacific Northwest will continue to move through the area through 06Z, flattening the upper ridge and putting the area under a westerly flow aloft. Mid and high level cloudiness has spread out over the area ahead of the disturbance this evening. The airmass is somewhat unstable along and south of a KDLN-KBZN line, where thunderstorms have developed with gusty winds and brief heavy rain. However, the airmass is significantly less unstable north of the line, so am not expecting storms there. Clouds will decrease from west to east after 04Z as the disturbance moves into the area. A weak cold front will accompany the disturbance, shifting the southwesterly winds more northwesterly from northwest to southeast over the central Montana plains between 06Z and 15Z. Coulston && .PREV DISCUSSION...Issued 232 PM MDT Wed Jul 9 2014 Today through Friday...Southwest Montana will become slightly unstable this afternoon as an increase in moisture should bring scattered thunderstorms to the area. Moderate shear could allow for the development of some stronger cells. Precipitable water is somewhat high meaning some storms could produce brief heavy rain. Activity diminishes by midnight tonight. Thursday and Friday look to be much of the same with the days starting out quiet before afternoon convection over far Southwest Montana. Temperatures will remain warm and winds may be a bit breezy at times. Friday night through Wednesday...The main upper level ridge of high pressure that is residing over the region will slowly be shifting/retrograde a bit more to the west from Saturday through Tuesday. As a result...the warmest temperatures will likely be staying west of the divide and over the Pacific Northwest. Never-the-less...it will still be quite warm/very warm for Saturday and Sunday...then seasonable/warm temperatures will reside over the region from Monday thru Wednesday. In terms of precipitation...no real organized areas of precipitation is expected from Friday through Sunday...other than some passing monsoonal moisture. Thus the chances for thunderstorms are generally isolated during this period...and mainly over Central and Southwest Montana. For Monday/Tuesday...the GFS tries to develop a bit more widespread thunderstorm activity along the front range of the Rockies and then southward into Southwest MT. Thus pops have been increased a bit...but overall coverage still looks to be scattered at this time. The thunderstorm activity starts to decrease a bit by next Wednesday...as the upper level ridge will start to shift/wobble back east a bit...also resulting in slightly warmer temperatures. Brusda && .PRELIMINARY POINT TEMPS/POPS... GTF 60 86 56 84 / 10 10 10 10 CTB 55 79 50 80 / 10 10 20 0 HLN 62 90 57 88 / 20 10 10 10 BZN 57 87 53 87 / 30 10 20 20 WEY 47 78 44 81 / 40 20 20 40 DLN 57 86 54 88 / 30 10 10 10 HVR 61 88 53 87 / 10 10 20 10 LWT 60 86 53 84 / 30 10 10 10 && .TFX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ weather.gov/greatfalls www.twitter.com/NWSGreatFalls www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
801 PM CDT WED JUL 9 2014 .SHORT TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 319 PM CDT WED JUL 9 2014 MODELS IN RELATIVELY DECENT AGREEMENT LARGE SCALE FLOW OVER MOST OF THE CONUS WILL BE NEAR ZONAL WHILE A POTENT SHORTWAVE TROF RUSHES ACROSS CANADA. HEADING INTO THE WEEKEND THEN...PATTERN IS PROGGED TO BEGIN AMPLIFYING WITH AN UPSTREAM RIDGE BECOMING ESTABLISHED OVER THE WRN CONUS BY SAT AFTN. MEANWHILE...GULF MOISTURE ADVECTION WILL BEGIN IN EARNEST LATER TONIGHT AS SFC HIGH PRESSURE SLIDES EAST AND ALLOWS MOISTURE TO SLIDE UP ALONG THE WRN HIGH PLAINS. APPEARS THAT MOISTURE RICH ENVIRONMENT WILL BE IN PLACE THEN THRU THE FCST PD. CURRENT RADAR MOSAIC WAS SHOWING CLUSTER OF TSTMS FROM S-CNTRL SD INTO N-CNTRL NEB MOVING SE WITHIN POCKET OF MID LYR ISENTROPIC UPGLIDE. LATEST HRRR SUGGESTING AREA OF CONVECTION WILL GRADUALLY INCREASE IN AREAL COVERAGE AND EXPAND INTO THE WRN CWA THEN EARLY THIS EVENING AND POSSIBLY THE REST OF THE CWA OVERNIGHT. OTHERWISE...MAIN ISSUE IS PINNING DOWN PLACEMENT/TIMING THUNDER POPS THE NEXT COUPLE DAYS. HOWEVER...REASONABLE ASSUME ON THUR NIGHT/FRI NIGHT...LLVL JET AND FAVORABLE FRONTOGENETIC FORCING/THETA-E CONVG WITHIN BNDRY LYR WILL HELP INDUCE NOCTURNAL TSTM ACTIVITY. AS FOR SVR TSTMS...NAM IS ADVERTISING POSSIBLE SVR DEVELOPMENT THUR NIGHT OVER N-CNTRL NEB WITH MUCAPES 2000-2500 J/KG AND ADEQUATE VERTICAL SHEAR. ALL THIS IN PART TO LEESIDE SFC LOW AND ATTENDANT THERMAL BNDRY EXTENDING FROM ABOUT NERN CO TO NERN SD. GFS INSTABILITY/SHEAR AT THAT TIME THOUGH IS SUBSTANTIALLY WEAKER. NEVERTHELESS...SITUATION BEARS WATCHING. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 319 PM CDT WED JUL 9 2014 RATHER GOOD AGREEMENT BTWN CMC/ECM/GFS EARLY ON THAT AMPLIFICATION WILL CONTINUE INTO EARLY NEXT WEEK WITH A HIGHLY ANOMALOUS UPPER TROF OVER THE ERN CONUS AND UPSTREAM RIDGE OVER THE WRN CONUS. AT THIS POINT DETERMINISTIC ECM/GFS AS WELL AS ECMENS/CMCENS ALL INDICATE LARGE SCALE FLOW WILL BECOME STAGNANT AND ALLOW A RATHER COOL AIRMASS FOR THIS TIME OF THE SEASON TO EXPAND SWD INTO THE REGION DAY 6 AND 7. EXPECT THEN A GOOD CHUNK OF THE CNTRL PLAINS WILL SEE WELL BELOW NORMAL AFTN TEMPS TUES AND WED. GOING POPS IN THE EXT PDS LOOK GOOD FOR NOW SO NO MAJOR CHANGES PLANNED. && .AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 755 PM CDT WED JUL 9 2014 THUNDERSTORMS CONTINUE TO SKIRT THE WESTERN EDGE OF A LINE FROM KOFK TO KLNK AS OF 01Z. EXPECT STORMS TO GRADUALLY SHIFT MORE TO THE EAST THROUGH 06Z WITH PERIODS OF THUNDERSTORMS POSSIBLE AT BOTH KOFK AND KLNK DURING THAT TIME. LATEST RAP MODEL MAINTAINS AN AREA OF SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST PARTS OF NEBRASKA THROUGH 17Z WITH EASTERN EDGE REACHING KOMA BY 12Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE LONG TERM...DEE AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS ELKO NV
252 PM PDT TUE JUL 8 2014 .SYNOPSIS... MOIST AIR MASS WILL KEEP THREAT OF THUNDERSTORMS OVER CENTRAL AND EASTERN NEVADA THROUGH THURSDAY. SOME STORMS WILL PRODUCE LOCALLY HEAVY RAINFALL. DRIER AIR WILL THEN MOVE THROUGH THE REGION FRIDAY AND PUSH THE THUNDERSTORM CHANCES TO AREAS NORTH OF INTERSTATE 80. DRY CONDITIONS ARE EXPECTED SATURDAY THROUGH NEXT TUESDAY. && .SHORT TERM... SHOWERS AND THUNDERSTORMS HAVE DEVELOPED MAINLY SOUTH OF INTERSTATE 80 TO FROM NORTHERN NYE COUNTY SO FAR TODAY. LATEST GUIDANCE INCLUDING HRRR MODEL KEEPS THE CONVECTIVE ACTIVITY GOING ACROSS MOST AREAS THROUGH THIS EVENING, EXCEPT FOR LESS COVERAGE ACROSS ELKO AND FAR NORTHERN HUMBOLDT COUNTIES. DEW POINTS RANGE FROM THE 20S AND 30S FROM I-80 NORTHWARD, TO THE LOWER 50S ACROSS NORTHERN NYE COUNTY. AS CELLS MOVE NORTH INTO THE DRIER AIR MASS, SOME OUTFLOW GUSTS COULD EXCEED 40 MPH THIS EVENING. OTHERWISE, THE MAIN IMPACT WILL BE LOCALLY HEAVY RAINFALL AND FREQUENT LIGHTNING. ISOLATED CELLS WILL CONTINUE OVERNIGHT DUE TO RESIDUAL MOISTURE AND WEAK SHORTWAVE ENERGY ROTATING INTO CENTRAL NV, WITH ANOTHER ROUND OF SCATTERED TO WIDESPREAD THUNDERSTORM FORMATION REGIONWIDE. HIGHER DEW POINTS IN THE 40S TO LOWER 50S WILL SPREAD NORTH TO THE OREGON AND IDAHO BORDERS. THE ONLY LIMITING FACTOR WOULD BE EXCESSIVE CLOUD COVER LIMITING DAYTIME HEATING, BUT THERE SHOULD BE ENOUGH BREAKS IN CLOUD COVER AND SUFFICIENT FORCING TO PRODUCE THUNDERSTORMS, WITH SLOW CELL MOTIONS AND HIGH PRECIPITABLE WATER VALUES LEADING TO HEAVY RAINFALL AND POSSIBLE LOCAL FLOODING. BY THURSDAY, ANOTHER SHORTWAVE WILL BRING ONE MORE ROUND OF THUNDERSTORMS MAINLY NORTH OF HIGHWAY 50, WITH LOCALLY HEAVY RAINFALL AGAIN POSSIBLE. BY THIS TIME, AREAS THAT BECOME SATURATED FROM RAINFALL TODAY OR WEDNESDAY MAY NEED TO BE WATCHED FOR POSSIBLE FLASH FLOOD WATCH. SOUTH OF HIGHWAY 50, DRIER AIR WILL BEGIN TO SPREAD NORTH, REDUCING THE COVERAGE OF THUNDERSTORMS. IN AREAS NOT COVERED ALL DAY BY CLOUD COVER, DAYTIME HIGHS SHOULD REACH THE 90S IN MOST LOWER ELEVATIONS BELOW 5500 FEET, AND MID TO UPPER 80S ABOVE 5500 FEET. MIN TEMPS WILL BE MUCH HIGHER THAN AVERAGE DUE TO THE MOIST AIR MASS AND CLOUD COVER, WITH LOWS MAINLY IN THE 60S. MJD .LONG TERM...FRIDAY THROUGH TUESDAY... FOR FRIDAY, THE MOISTURE WILL CONTINUE DECREASING FROM SOUTH TO NORTH, RESULTING IN THUNDERSTORMS GENERALLY LIMITED TO NORTH OF INTERSTATE 80 WITH DECREASED COVERAGE COMPARED TO THURSDAY. OTHERWISE FROM SATURDAY THROUGH TUESDAY, HIGH PRESSURE RIDGE REBUILDING OVER THE FOUR CORNERS REGION WILL BRING DRIER AND MORE STABLE AIR MASS TO THE REGION, ENDING THE THREAT OF THUNDERSTORMS. TEMPERATURES WILL REMAIN ABOVE NORMAL WITH HIGHS APPROACHING 100 DEGREES IN SOME OF THE WARMER VALLEYS. MJD && .AVIATION... THUNDERSTORMS WILL PRODUCE THE MAIN AVIATION IMPACTS THROUGH THURSDAY. COVERAGE WILL BE GREATEST DURING THE AFTERNOON AND EVENING, BUT SOME CELLS WILL LINGER THROUGH THE OVERNIGHT AND MORNING HOURS. HEAVY RAIN WILL BE THE MAIN THREAT, ALTHOUGH THIS EVENING SOME OUTFLOW GUSTS COULD EXCEED 35 KT ESPECIALLY NEAR AND NORTH OF I-80 AS INITIAL CELLS ENCOUNTER DRIER AIR MASS. MJD && .FIRE WEATHER... WHILE NUMEROUS LIGHTNING STRIKES (LAL AS HIGH AS 4 IN SOME AREAS) ARE EXPECTED THROUGH THURSDAY, THE SLOW CELL MOVEMENT AND HIGH PRECIPITABLE WATER VALUES WILL RESULT IN MOST STORMS PRODUCING WETTING RAINS. THIS SHOULD LIMIT SPREAD OF ANY LIGHTNING-INDUCED FIRE STARTS, IF ANY OCCUR. MJD && .LKN WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1050 PM EDT WED JUL 9 2014 .SYNOPSIS...CYCLONIC FLOW ALOFT WILL PREVAIL OVER THE REGION THROUGH FRIDAY. MEANWHILE...A STALLED FRONT WILL PERSIST ACROSS THE CAROLINAS THROUGH FRIDAY. && .NEAR TERM /OVERNIGHT/... AS OF 1045 PM WEDNESDAY... CYCLONIC FLOW ALOFT WILL PREVAIL ACROSS THE REGION OVERNIGHT... FOSTERING A POTENTIAL FOR DPVA ASSOCIATED WITH SMALL AMPLITUDE DISTURBANCES TRACKING EAST FROM THE TN/OH VALLEY INTO THE MID- ATLANTIC AND NORTH CAROLINA. GIVEN THE PRESENCE OF MARGINAL NOCTURNAL INSTABILITY (500-1000 J/KG MUCAPE) AND THE PRESENCE OF A SHORTWAVE JUST UPSTREAM OVER TN/KY (PER RAP DATA AND WV IMAGERY)... WILL CONTINUE TO INDICATE A SLIGHT CHANCE OF SHOWERS/STORMS THROUGHOUT THE NIGHT. EXPECT LOWS IN THE LOWER 70S. -VINCENT && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 230 PM WEDNESDAY... SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR AGAIN ON THURSDAY AS A SERIES OF WEAK DISTURBANCES MOVE NE ACROSS OUR AREA IN ADVANCE OF THE MID-LEVEL TROUGH AXIS TO OUR WEST. AT THE SFC...THE COLD FRONT CURRENTLY TO OUR NW WILL DROP SOUTH AND MERGE WITH THE PIEDMONT TROUGH...PROVIDING A LOW LEVEL FOCUS FOR CONVECTION INITIATION. NOTED THAT GUIDANCE SHOWS AN AXIS OF HIGH PWAT (AROUND 2 INCHES) WILL PERSIST ACROSS THE EASTERN 2/3 OF OUR CWA DURING THE AFTERNOON INTO THE EVENING...TRENDING LOWER TO AROUND 1.5 INCHES ACROSS THE TRIAD. MEANWHILE...DEEP LAYER SHEAR WILL BE SIMILAR TO TODAY...25KT OR LESS. THUS...WHILE WE CAN`T RULE OUT THE POTENTIAL FOR AN ISOLATED STRONG WIND GUST OR TWO...THE MAIN IMPACTS MAY INSTEAD BE HEAVY RAIN INVOF OF THE BELT OF HIGH PWAT...AND THE POTENTIAL FOR LOCALIZED POOR DRAINAGE FLOODING WITH ANY OF THE SLOWER CELLS OR LOCATIONS THAT SEE REPETITIVE DOWNPOURS. GIVEN THIS MOISTURE PROFILE...LOOK FOR THE BEST COVERAGE AND THUS HIGHEST POPS TO BE EAST OF THE TRIAD. SIMILAR TO TODAY...HIGHS WILL BE DEPENDENT ON CLOUD COVERAGE...WHICH MAY BE MORE WIDESPREAD ACROSS OUR CWA TOMORROW COMPARED TO TODAY. HIGHS IN THE MID-UPR 80S AND LOWS THURSDAY NIGHT IN THE UPPER 60S TO AROUND 70. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... AS OF 245 PM WEDNESDAY... FOR FRI THROUGH SAT NIGHT: THE WEAKENING MID LEVEL TROUGH AXIS SHIFTS EAST OF THE SRN APPALACHIANS FRI... BEFORE SWEEPING OVERHEAD FRI NIGHT AND TO OUR EAST SAT. THE WEAK SURFACE TROUGH WILL ROUGHLY FOLLOW THIS PACE AS WELL... SETTLING OVER THE COASTAL CAROLINAS BY SAT MORNING BEFORE LARGELY DISSIPATING. THE EASTERN HALF OF NC WILL REMAIN WITHIN SUFFICIENTLY DEEP MOISTURE FRI FOR MAINLY AFTERNOON/EVENING SHOWERS AND STORMS... WHILE A DRIER COLUMN... SLIGHT RISE IN HEIGHTS ALOFT... AND DOWNSLOPE LOW LEVEL FLOW OVER THE WEST WILL LIMIT CONVECTION THERE... A PATTERN SUPPORTED BY THE LATEST SREF PROBABILITIES OF CONVECTIVE PRECIP. THE GFS SHOWS MUCAPE PEAKING AT 1500-2000 J/KG BUT SUBPAR DEEP LAYER SHEAR OF JUST AROUND 20 KTS OR SO... SO EXPECT ANOTHER ROUND OF WEAKLY FORCED AND SLOW MOVING MULTICELL CLUSTER WITH SUPPRESSED SEVERITY BUT THE POTENTIAL FOR TRAINING CELLS AND LOCALLY HEAVY RAIN GIVEN THE PW HOLDING NEAR 2.0 INCHES EAST OF HIGHWAY 1. THE SHEAR AXIS BROADENS AND WEAKENS FURTHER ON SAT WITH MINOR RISES IN HEIGHTS ALOFT. ANY TRACE OF THE SURFACE TROUGH IS TOUGH TO DETECT ON THE MODEL OUTPUT WITH A FAIRLY UNIFORM LIGHT LOW LEVEL FLOW FROM THE S AND SE. MODELS SHOW CENTRAL AND WRN NC WITHIN A RELATIVE PW MINIMUM... BETWEEN THE 1.5+ INCH VALUES OVER COASTAL NC AND ERN SC... AND THE HIGHER VALUES PUSHING INTO THE OH VALLEY ASSOCIATED WITH WHAT WILL LIKELY BE AN MCS CROSSING THE MIDWEST AND SOUTHERN END OF THE GREAT LAKES SAT/SAT NIGHT. BUT ANY AMOUNT OF ATLANTIC-SOURCE LOW LEVEL INFLOW COMBINED WITH HEATING COULD GENERATE DISORGANIZED ISOLATED TO SCATTERED PULSE CONVECTION IN THE AFTERNOON. WILL HAVE POPS ON THE LOW END... 20-30% ORIENTED NW TO SE RESPECTIVELY...SAT AFTERNOON/EVENING. THICKNESSES BOTH FRI AND SAT STAY SLIGHTLY BELOW NORMAL...WITH A BIT MORE SUNSHINE ANTICIPATED SAT THAN FRI... SO WILL HOLD ONTO HIGHS FROM THE MID 80S TO NEAR 90 WITH LOWS IN THE UPPER 60S TO LOWER 70S. FOR SUN-WED: DEEP LAYER WIND FIELDS REMAIN VERY WEAK SUNDAY WITH ONLY A SUBTLE SURFACE TROUGH EVIDENT THROUGH THE PIEDMONT... HOWEVER WE WILL START TO SEE PW VALUES RECOVER BACK UP ABOVE SEASONAL NORMALS... SUGGESTING A TREND BACK TO MORE SEASONALLY TYPICAL COVERAGE OF AFTERNOON PULSE CONVECTION FOR SUNDAY. AN ANOMALOUSLY STRONG MID LEVEL VORTEX (MID LEVEL HEIGHTS AS LOW S 2-3 STANDARD DEVIATIONS BELOW NORMAL) AS LOW AS WILL WOBBLE EASTWARD ACROSS SRN ONTARIO AND THE NRN GREAT LAKES SUN-TUE THEN INTO QUEBEC WED... AND THIS BROAD TROUGHING OVER ERN NOAM WILL MEAN INCREASINGLY UNSETTLED WEATHER FOR NC... WITH SW LOW LEVEL AHEAD OF THE SLOWLY APPROACHING SURFACE COLD FRONT... AND STRENGTHENING MID LEVEL WESTERLY FLOW FOSTERING BETTER STORM ORGANIZATION. WILL PLACE GOOD CHANCES OF SHOWERS AND STORMS FOCUSED ON EACH AFTERNOON/EVENING MON-TUE... WITH PERHAPS A SOUTHEASTWARD SHIFT OF THE HIGHER POPS WED TO LEVERAGE THE POSSIBILITY THAT THE SURFACE FRONT MIGHT DROP SE INTO THE CWA AND PUSH THE BETTER MOISTURE INTO SRN/ERN NC. SEE NOTHING TO INDICATE A MAJOR DEPARTURE FROM CLIMATOLOGICAL TEMPS... AS GREATER-THAN-USUAL CLOUD COVER WITH HEATING EACH DAY WILL MODULATE SLIGHTLY ABOVE- NORMAL THICKNESSES... SO WILL STICK WITH DAILY HIGHS IN THE UPPER 80S TO LOWER 90S... AND DAILY LOWS NEAR 70 TO THE LOWER 70S. -GIH && AVIATION /00Z THURSDAY THROUGH MONDAY/... AS OF 700 PM WEDNESDAY... 24 HOUR TAF PERIOD: SHOWERS AND THUNDERSTORMS CURRENTLY AFFECTING THE TRIAD WILL MOVE EASTWARD OVER THE NEXT SEVERAL HOURS. ANOTHER BOUNDARY IN THE EXTREME EASTWARD SIDE OF THE AREA IS ALSO PRODUCING CONVECTION BUT SHOULD MOVE OFF TO THE EAST. ALL IN ALL CONVECTION SEEMS TO BE WINDING DOWN WITH THE EXCEPTION BEING MAYBE ACROSS THE NORTH AND EAST. WILL CONTINUE TO MENTION SHOWERS IN THE TAFS AT KRDU AND KRWI AS THEY ARE THE MOST LIKELY TO BE AFFECTED OVER THE NEXT SEVERAL HOURS. EXPECT LIGHT SOUTHWESTERLY WINDS OVERNIGHT AT 5-10 KTS. THERE COULD BE POCKETS OF FOG OR LOW STRATUS OVERNIGHT..ESPECIALLY WHERE THERE HAS BEEN CONVECTION BUT CONFIDENCE IN THIS IS LOW AND IT WILL BE LEFT OUT OF THE TAFS AT THIS TIME. THERE MAY BE SOME IMPROVED CONDITIONS AROUND DAYBREAK BUT THESE WILL QUICKLY GO DOWN HILL DURING THE AFTERNOON AS CONVECTION IS EXPECTED TO BE FAIRLY WIDESPREAD AS A COLD FRONT MOVES IN FROM THE NORTHWEST. WILL COVER WITH A PROB 30 GROUP AFTER 18Z BUT A GOOD CHANCE FOR PROLONGED MVFR CONDITIONS AT ALL SITES TOMORROW AFTERNOON WITH CEILINGS NEAR 3 KFT AND 5 SM VISIBILITIES POSSIBLE. THIS IS EXPECTED TO CONTINUE THROUGH THE END OF THE TAF PERIOD. LONG TERM: THERE WILL BE CONTINUED CHANCES FOR SUB-VFR CONDITIONS THROUGH MONDAY WITH THE LEAST COVERAGE SATURDAY AND SUNDAY BUT STILL A CHANCE FOR DIURNAL CONVECTION...ESPECIALLY IN THE EAST. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...VINCENT SHORT TERM...NP LONG TERM...HARTFIELD AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
749 PM EDT WED JUL 9 2014 .SYNOPSIS... A COLD FRONT WILL STALL OVER THE REGION LATE THURSDAY INTO EARLY SATURDAY...BRINGING GOOD CHANCES FOR THUNDERSTORMS. THIS FRONT WILL DISSIPATE LATE IN THE WEEKEND WITH A RETURN TO TYPICAL SUMMERTIME CONDITIONS BY EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 730 PM WEDNESDAY...HOT SOUTHWEST FLOW AROUND THE WESTERN EDGE OF BERMUDA HIGH PRESSURE BROUGHT FLORENCE ITS FIRST 100 DEGREE READING OF THE YEAR TODAY. TEMPERATURES IN THE MID TO UPPER 90S WERE WIDESPREAD AWAY FROM THE BEACHES. ALL THIS HEAT INLAND MIXED DRY DOWN FROM ALOFT INLAND...LIMITING CONVECTIVE COVERAGE AS SURFACE-BASED CAPE DROPPED TO ONLY A FEW HUNDRED J/KG. LATE TONIGHT MOISTURE WILL INCREASE THROUGH A DEEP LAYER OF THE ATMOSPHERE VIA CONTINUED SOUTHWEST FLOW FROM THE SURFACE UP THROUGH 25000 FEET. DESPITE MODEST LAPSE RATES ALOFT THIS INCREASE IN MOISTURE SHOULD PRODUCE ELEVATED CAPE ON THE ORDER OF 500-1000 J/KG BEFORE DAYBREAK. I HAVE TRIMMED BACK POPS SHARPLY THROUGH THE EVENING HOURS BUT WILL STILL SHOW 20-30 PERCENT CHANCES FOR A SHOWER OR T-STORM LATE TONIGHT...ESPECIALLY INLAND WHERE THE MID-LEVEL MOISTURE RETURN SHOULD OCCUR FIRST. FOR THE PAST TWO NIGHTS GFS AND NAM MOS LOWS HAVE BEEN PRETTY ABYSMAL. BIAS CORRECTION BASED ON THE PAST TWO NIGHTS WAS USED TO MODIFY TONIGHT`S FORECAST LOWS...ANTICIPATED TO RANGE FROM THE MID 70S INLAND TO AROUND 80 ON THE BEACHES. PREVIOUS DISCUSSION FROM 230 PM FOLLOWS... FINE CU FIELD BUILDING RIGHT ALONG SEA BREEZE BOUNDARY AS IT MAKES ITS WAY INLAND THROUGH THIS AFTERNOON...LEAVING TIP OF CAPE FEAR THE SUNNIEST SPOT. HRRR MODEL FORECAST HOLDING WELL SO FAR AS BROKEN LINE OF CONVECTION STREAMING FROM SOUTHWEST TO NORTHEAST JUST WEST OF FORECAST AREA. MODELS SHOWED THIS LINE DIMINISHING AS IT PUSHES EASTWARD THROUGH EARLY THIS EVENING. WILL KEEP POPS AS IS WITH POSSIBILITY OF AN ISOLATED SHWR ALONG SEA BREEZE AND CHC POPS OVER INLAND COUNTIES MAINLY LATER TODAY. DEW POINT TEMPS WILL HOLD IN THE MID 60S INLAND THROUGH THIS AFTERNOON AND CLOSER TO 70 ALONG THE COAST IN A CONTINUED SOUTHWEST FLOW OF WARM AND MOIST AIR AT THE SURFACE AROUND BERMUDA HIGH. OVERALL VERY WARM DAY WITH SPOTTY CU FIELD LEAVING A GOOD DEAL OF SUNSHINE AND TEMPS INTO THE 90S MOST PLACES. LATEST MOISTURE PROFILES KEEP VERY DRY MID LEVELS THROUGH MUCH OF TONIGHT AS MID TO UPPER RIDGE HOLDS ON FOR ONE LAST DAY. CONVECTIVE PARAMETERS BECOME MORE FAVORABLE THIS EVENING BUT SUPPORT FOR CONVECTION WILL DIMINISH THROUGH THIS EVENING AS HEATING OF THE DAY CUTS OFF. THE MAIN FOCUS FOR CONVECTION WILL LIE MAINLY TO OUR WEST AS PIEDMONT TROUGH AND AN APPROACHING COLD FRONT DRIVE MUCH OF THE CONVECTIVE ACTIVITY. A DEEPENING UPPER TROUGH OVER EASTERN CONUS WILL PUSH EAST PROVIDING MUCH GREATER SUPPORT FOR CONVECTION AND THIS MAY REACH FAR ENOUGH INTO THE CAROLINAS BY THIS EVENING TO TRIGGER SOME SHWRS/TSTMS WHICH MAY REACH INTO WESTERN REACHES OF FORECAST AREA BY THIS EVENING THIS COLD FRONT WILL PUSH EAST WITH PLENTY OF MOISTURE POOLING AHEAD OF IT AND INCREASED UPPER LEVEL SUPPORT HEADING INTO THURS. MAY SEE SOME SHWRS/TSTMS AROUND OVERNIGHT INTO EARLY THURS BUT MAIN ACTIVITY WILL COME LATER IN THE DAY. ANOTHER WARM NIGHT AHEAD WITH TEMPS DROPPING BUT REMAINING IN THE 70S. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...AN UPPER LEVEL TROUGH AND SURFACE COLD FRONT WILL BE SHIFTING INTO THE AREA. AT THE SURFACE THIS FRONT WILL STALL AND ABOVE THE SURFACE PRECIPITABLE WATERS WILL INCREASE TO 2 PLUS INCHES. THE FLOW ALOFT WILL PARALLEL THE FRONT AND THE 850 TO 700 MB WINDS WILL BE AT 10 TO 15 KNOTS. EVEN HIGHER THE UPPER LEVEL FORCING FROM THE 300 MB JET WILL INCREASE SYNOPTIC SCALE LIFT. SO THE POSSIBILITY OF HEAVY RAIN OVER THE AREA THURSDAY AFTERNOON THROUGH FRIDAY MIDDAY CONTINUE TO BE HIGH. BY FRIDAY MIDDAY THE SYNOPTIC SCALE VORTICITY HAS SHIFTED OFFSHORE AND IT WILL DRAG THE DEEPER MOISTURE WITH IT. EXPECT THE CHANCES FOR THE HEAVY RAIN TO DIMINISHED AT THIS TIME. MAXIMUM TEMPERATURES WILL REACH THE LOWER 90S ON THURSDAY IF THE CONVECTION HOLD OFF AND CLOUDS AND RAIN DO NOT COOL THE ATMOSPHERE TO QUICKLY. EXPECT HIGHS TO BE EVEN LOWER WITH CLOUDS AND RAIN KEEP THE HIGHS AT BAY AND REACHING INTO THE UPPER 80S. LOW TEMPERATURES WILL BE IN THE MID 70S THURSDAY NIGHT AND THE LOWER 70S FRIDAY NIGHT. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 PM WEDNESDAY...REMAINS OF COLD FRONT STILL SHOWING UP STALLED ACROSS THE AREA ON SATURDAY. BETWEEN SOME UNCERTAINTY AS TO WHERE IT STALLS PAIRED WITH MODEL DISAGREEMENT REGARDING WHICH SIDE OF THE BOUNDARY IS FAVORED FOR PRECIP WILL STICK WITH PREVIOUS AREA-WIDE 40-ISH POP. THE BOUNDARY WASHES OUT ON SUNDAY AND A VERY WEAK PIEDMONT TROUGH MAY BE DEVELOPING. ITS STILL HARD TO SHOW ANY PARTICULAR FAVORED AREA FOR POPS BUT WILL SHOW A SMALL DOWNWARD TREND DUE TO SOME MID LEVEL DRYING. MONDAY SHOULD OFFER SEASONABLE TEMPERATURES AND A SEASONABLE DISTRIBUTION OF DIURNAL CONVECTION AS THE AREA FINDS ITSELF BETWEEN A VERY WEAK UPPER RIDGE OVER FL AND AN UNSEASONABLY LARGE/STRONG VORTEX DROPPING INTO THE GREAT LAKES. TUESDAY AND WEDNESDAY FEATURE A RETURN OF THE PIEDMONT TROUGH AND A SLIGHT VEERING OF THE MID LEVEL FLOW FROM THE AFOREMENTIONED UPPER LOW. RAINFALL CHANCES SHOULD INCREASE JUST SLIGHTLY WHILE TEMPS REMAIN NEAR NORMAL. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... AS OF 00Z...PATCHY AREAS OF FOG OVERNIGHT COULD CREATE BRIEF-MVFR INLAND...AND INCREASING CHANCES FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED ON THURSDAY POSSIBLY CREATING MVFR/IFR ESPECIALLY IN HEAVIER DOWNPOURS. OTHERWISE EXPECT VFR. VFR PREVAILS THIS EVENING WITH SOUTHWEST WINDS AOB 10 KTS...AND HIGHER GUSTS ALONG THE COAST...WHICH ARE EXPECTED TO SUBSIDE WITHIN THE NEXT FEW HOURS. RADAR IMAGERY OVERALL QUIET ACROSS THE AREA WITH A FEW ISOLATED SHOWERS JUST TO THE WEST/NORTHWEST...WHICH COULD POSSIBLY MOVE NEAR THE INLAND SITES. HOWEVER DO NOT ANTICIPATE ANY RESTRICTIONS. PATCHY AREAS OF FOG OVERNIGHT COULD CREATE BRIEF MVFR INLAND INTO THE EARLY MORNING AS WELL BUT CONFIDENCE REMAINS LOW. ON THURSDAY...EXPECT INCREASING CLOUDS AND CHANCES FOR SHRA/TSRA THROUGHOUT THE DAY. HEAVY DOWNPOURS ARE EXPECTED GIVEN THE FAVORABLE ENVIRONMENT...THUS ANTICIPATE PERIODS OF MVFR/IFR. AS FOR WINDS...EXPECT SOUTH-SOUTHWEST WINDS AOB 10 KTS INLAND AND UP TO AROUND 15 KTS WITH GUSTS ALONG THE COAST. EXTENDED OUTLOOK...A FRONT STALLS OVER THE REGION WITH A DECENT CHANCE FOR CONVECTION THROUGH SATURDAY...MAINLY IN THE AFTERNOON. MORE SHOWERS AND STORMS ARE POSSIBLE MONDAY. BRIEF IFR CONDITIONS ARE POSSIBLE IN THE HEAVIER SHOWERS AND STORMS. OTHERWISE EXPECT VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 730 PM WEDNESDAY...MUCH LIKE LAST NIGHT WINDS ARE GUSTING 22-26 KNOTS AT OBSERVATION SITES ALONG THE BEACHES...COURTESY OF THE AFTERNOON SEABREEZE PLUS A TIGHT PRESSURE GRADIENT ALONG THE WESTERN EDGE OF THE BERMUDA HIGH. A LOW LEVEL JET SHOULD STRENGTHEN OVERHEAD AGAIN THIS EVENING WITH 1000 FOOT WINDS INCREASING TO 25-30 KNOTS...BUT SHOULD ALSO DIE AWAY FASTER THAN IT DID LAST NIGHT. AVERAGE WIND SPEEDS TONIGHT SHOULD BE 15-20 KT. SEAS ARE AROUND 4 FEET AT THE NEARSHORE WRIGHTSVILLE BEACH BUOY...WITH LITTLE CHANGE EXPECTED OVERNIGHT. PREVIOUS DISCUSSION FROM 230 PM FOLLOWS... SOUTHWESTERLY FLOW WILL CONTINUE OVER THE WATERS THROUGH TONIGHT BETWEEN HIGH PRESSURE OVER THE WESTERN ATLANTIC AND TROUGH OF LOW PRESSURE INLAND. SEAS WILL REMAIN BETWEEN 2 AND 4 FT AS GRADIENT WEAKENS THROUGH THE NIGHT LEAVING WINDS OF 15 KTS OR LESS. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...AS A COLD FRONT APPROACHES THE COAST LATE THURSDAY THE SOUTHWEST WINDS WILL INCREASE TO 15 KNOTS BUT THE WINDS WILL WEAKEN AS THE FRONTAL BOUNDARY STALLS AT THE COAST AND THE PRESSURE GRADIENT WEAKENS FRIDAY. SEAS ARE EXPECTED TO BE AROUND 3 FEET ON THURSDAY BUT WILL SLOWLY DIMINISH TO 2 FEET BY FRIDAY NIGHT IN RESPONSE TO THE WINDS. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 3 PM WEDNESDAY...LIGHT WINDS EXPECTED ON SATURDAY WITH A WEAKENING FRONT STALLED ACROSS THE AREA. THIS BOUNDARY WILL CAST A SMALL DEGREE OF UNCERTAINTY WITH RESPECT TO WIND DIRECTION BUT SOUTHERLY FLOW GENERALLY EXPECTED TO BE PREDOMINANT. THIS BOUNDARY WASHES OUT BY SUNDAY AS A WEAK PIEDMONT TROUGH DEVELOPS. THIS MAY BE GOOD FOR ABOUT A 5KT/1FT INCREASE IN CONDITIONS. A SIMILAR OR EVEN LARGER INCREASE IN WINDS AND SEAS MAY BE SLATED FOR MONDAY. BROAD CYCLONIC CURVATURE AROUND A LARGE STORM NORTH OF THE GREAT LAKES RESPONSIBLE FOR TIGHTENING THE GRADIENT LOCALLY. HEADLINES OR EVEN AND ADVISORY APPEAR POSSIBLE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...RGZ/TRA SHORT TERM...HAWKINS LONG TERM...MBB AVIATION...SGL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
230 PM EDT TUE JUL 8 2014 .SYNOPSIS...BROAD HIGH PRESSURE WEAKENS AS A COLD FRONT MOVES TOWARD THE REGION FROM THE GREAT LAKES. THIS COLD FRONT SHOULD MOVE INTO THE MID-ATLANTIC WEDNESDAY...WEAKENING AS IT MOVES INTO NORTH CAROLINA THURSDAY. A TROUGH OF LOW PRESSURE THEN PERSISTS OVER THE REGION AT LEAST THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 910 AM TUESDAY... THE LATEST SURFACE ANALYSIS SHOWED BROAD HIGH PRESSURE MOSTLY OVER THE MID-ATLANTIC AND THE CAROLINAS WITH A WEAK SURFACE TROUGH AMONG THE BROAD RIDGE OVER THE CENTRAL PIEDMONT. THE SPC MESOANALYSIS SHOWED A NOTICEABLE MINIMUM OF PRECIPITABLE WATER VALUES OVER THE WESTERN PART OF THE STATE...SIMILAR TO WHAT WAS FORECAST BY THE MONDAY GUIDANCE. THE RAP FORECASTS THIS MINIMUM TO MOVE ACROSS CENTRAL NORTH CAROLINA DURING THE DAY...AND FOR THE MOST PART RAP SOUNDINGS ARE SIMILAR TO SOUNDINGS FORECAST BY THE GFS MONDAY... QUITE STABLE TO DEEP CONVECTION DURING THE DAY. TWO CAVEATS TO THIS ARE CURRENTLY...AND VERY LATE TODAY. CURRENTLY...PRECIPITABLE WATER VALUES ARE AT OR ABOVE 1.5 INCHES OVER A LARGE PART OF CENTRAL NORTH CAROLINA...AND RAP SOUNDINGS SHOW THE PRESENCE OF MID-LEVEL INSTABILITY THAT WANES BY 18Z AS THE LOWER MOISTURE VALUES MOVE EAST. THE LATEST VISIBLE IMAGERY SHOWED A NARROW BAND OF MID-LEVEL CLOUDS THAT DEVELOPED FROM NEAR ROXBORO TO WADESBORO...AND THE HRRR WRF ACTUALLY FORECASTS A SHOWER OR TWO DEVELOPING FROM THIS. WATER VAPOR IMAGERY WOULD SUGGEST ENOUGH SUBSIDENCE TO PRECLUDE A SHOWER... BUT THE DEVELOPMENT OF THE CLOUDS PLUS THE PRESENCE OF WEAK INSTABILITY MAKES IT WORTHY OF NOTE HERE. LATE TODAY...THE RAP FORECASTS LIFT MOVING INTO THE FAR NORTHWEST PIEDMONT TOWARD KINT BY 23Z. RAP SOUNDINGS ARE STILL FAIRLY STABLE AT THAT POINT...AND QPF ON THE RAP IS NIL THROUGH 00Z WEDNESDAY. PRECIPITABLE WATER VALUES INCREASE QUICKLY ON THE RAP...TO NEAR 1.5 INCHES JUST AFTER 00Z WEDNESDAY...AS K INDICES RISE TO NEAR 40. LIKE THE GFS FORECAST MONDAY...MODEST MID-LEVEL COOLING COUPLED WITH MOISTURE ADVECTION MAY BE ENOUGH FOR A SHOWER OR THUNDERSTORM TO MOVE INTO THE WEST AND NORTHWEST PIEDMONT THIS EVENING. MOS GUIDANCE POPS ARE A FEW PERCENTAGE POINTS LOWER THAN THAT GUIDANCE OF MONDAY...AND WRF ARW GUIDANCE SUGGESTS LITTLE PRECIPITATION INTO THE EVENING. STILL...THE MOISTURE ADVECTION AND SLIGHT COOLING ALOFT... COUPLED WITH A WEAKENING MID-LEVEL SHORTWAVE MOVING INTO THE WESTERN PIEDMONT THIS EVENING...IS ENOUGH TO AT LEAST CONTINUE THE SMALL CHANCES WEST AS CURRENTLY FORECAST THIS EVENING...AND MAY NEED TO EXPAND SLIGHTLY FARTHER EAST. THE 00Z GFS APPEARED TO SUFFER FROM SOME MINOR CONVECTIVE FEEDBACK WHILE THE ECMWF HAS BEEN VERY CONSISTENT IN SUGGESTING THE BEST THREAT FOR OVERNIGHT CONVECTION TO OUR NW. IT SHOULD ALSO BE NOTED THAT THE CONVECTIVE ALLOWING MODELS VERIFIED WAY OVERDONE ACROSS THE OH VALLEY INTO THE MID ATLANTIC AT 06Z. HIGHS TODAY IN THE LOWER TO MID 90S. WARM OVERNIGHT WITH LOWS NEAR 70 TO THE LOWER 70S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 310 AM TUESDAY... MID LEVEL SHEAR AXIS ASSOCIATED WITH THE NORTHERN STREAM S/W AND ITS ATTENDANT SURFACE BOUNDARY WILL DRIFT SEWD INTO CENTRAL NC WEDNESDAY AFTERNOON-WEDNESDAY NIGHT. THIS SYSTEM WILL INTERACT WITH STRONG HEATING AND AVAILABLE MOISTURE (PRECIPITABLE WATER VALUES IN THE NEIGHBORHOOD OF 1.67-1.9 INCHES) TO INITIATE AND SUSTAIN SCATTERED CONVECTION...ESPECIALLY WEDNESDAY AFTERNOON-WEDNESDAY EVENING. SOME CONVECTIVE PARAMETERS SUGGEST SOME POTENTIAL FOR ORGANIZED CONVECTION IN THE FORM OF BROKEN CONVECTIVE SEGMENTS. IF THESE SEGMENTS WERE TO DEVELOP...COULD SEE A DAMAGING WIND THREAT WITH THE STRONGER CELLS. THIS THREAT APPEARS GREATEST ACROSS THE NORTHERN PIEDMONT INTO THE NORTHERN COASTAL PLAIN (GENERALLY NORTH OF I-40) WHERE BULK SHEAR VALUES APPROACH 30 KTS. DUE TO PRESENCE OF SHEAR AXIS AND SFC BOUNDARY...EXPECT SCATTERED CONVECTION TO PERSIST WELL INTO THE NIGHT THOUGH OVERALL COVERAGE AND INTENSITY WILL DIMINISH AS NEAR SURFACE AIR MASS UNDERGOES NOCTURNAL STABILIZATION. HIGH TEMPS WEDNESDAY DEPENDENT UPON AMOUNT OF INSOLATION AND CONVECTIVE COVERAGE. IF SUN LIMITED DUE TO EXTENSIVE CLOUD COVERAGE OR IF THE GFS IS CORRECT AND SCATTERED CONVECTION IS OCCURRING AT THE THE START OF THE DAY...THEN MAX TEMPS ACROSS THE NORTH COULD END UP BEING 5-6 DEGREES COOLER THAN FORECAST. DUE TO ANTICIPATED TIMING...BELIEVE THAT THE SOUTHERN HALF OF THE FORECAST AREA STANDS A GOOD SHOT OF SEEING TEMPS RETURNING TO THE MID 90S. MIN TEMPS WEDNESDAY NIGHT IN THE UPPER 60S TO AROUND 70 NORTH AND LOWER 70S SOUTH. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AS OF 230 PM TUESDAY... FOR THU THROUGH FRI NIGHT: THU STILL APPEARS TO BE THE BUSIEST WEATHER DAY IN TERMS OF STORM COVERAGE. A SURFACE TROUGH WILL HOLD OVER CENTRAL NC THU... WITH ELEVATED LOW LEVEL MOISTURE TRANSPORT MAINLY EAST/SOUTH OF THE TRIAD. ALOFT... BROAD TROUGHING SETTING UP JUST TO OUR WEST WILL DRAW IN NRN STREAM ENERGY AS WELL AS PULL IN PERTURBATIONS FROM AN UPPER LEVEL WEAKNESS OVER THE WRN GULF OF MEXICO. WHILE THE TROUGH ITSELF WILL BE SOMEWHAT WEAK AT THIS LATITUDE WITH MINIMAL HEIGHT FALLS (10 M AT MOST ON THU) AND MLLR VALUES UNDER 6.5 C/KM... THE ADDED DYNAMIC FORCING FOR ASCENT SHOULD SUPPORT AT LEAST SCATTERED CONVECTION (MAXIMIZING IN -- BUT NOT RESTRICTED TO -- THE AFTERNOON/EVENING) DESPITE MARGINAL VALUES OF INSTABILITY DUE TO LAYERS OF A MOIST ADIABATIC PROFILE (NAM MLCAPE TOPPING OUT AT 500-1000 J/KG WITH GFS MUCAPE OF 1000-1500 J/KG IN THE EAST THU). FORECAST DEEP LAYER SHEAR VALUES ARE MORE FAVORABLE THAN YESTERDAY`S MODEL RUNS... NOW AROUND 25-35 KTS OVER NRN/WRN NC... INDICATING THE POTENTIAL FOR MORE ORGANIZED CONVECTION... ALTHOUGH THIS BETTER SHEAR WILL NOT QUITE BE SPATIALLY ALIGNED IN AN IDEAL MANNER WITH THE GREATER INSTABILITY. NEVERTHELESS... PW VALUES WILL REMAIN ABOVE NORMAL (1.7-2.0 IN.)... AND THIS MOISTURE COMBINED WITH LOW MBE TRANSLATIONAL SPEEDS AND A DECENT WARM CLOUD DEPTH NEAR 3.5 KM SUGGESTS THAT SOME SLOW-MOVING CELLS WITH EFFICIENT RAIN PROCESSES MAY GENERATE LOCALLY HEAVY RAINFALL. WILL BUMP UP POPS TO LIKELY... HIGHER EAST THAN WEST... ON THU EXTENDING INTO EARLY THU NIGHT... UNTIL THE MID LEVELS BEGIN TO DRY OUT A BIT. THE MID LEVEL TROUGH AXIS SHIFTS EAST OF THE SRN APPALACHIANS FRI... KEEPING ERN NC IN THE CROSSHAIRS OF SUFFICIENTLY DEEP MOISTURE AND MARGINAL SHEAR AND INSTABILITY... ENOUGH TO SUPPORT PRIMARILY AFTERNOON AND EVENING SHOWERS AND STORMS... WITH THE BEST CHANCES EAST OF I-95... ALONG/EAST OF WHERE THE SURFACE TROUGH SETTLES. EXPECT LOWER COVERAGE OVER THE REST OF CENTRAL NC WITH PW SLIPPING TO NEAR OR JUST BELOW NORMAL AND LOWER DEEP LAYER SHEAR (15-20 KTS)... ALTHOUGH GFS MUCAPE PEAKS ONCE AGAIN AT 1000-1500 J/KG OVER CENTRAL NC... SO CAN`T RULE OUT SCATTERED STORMS. WILL KEEP POPS RANGING FROM 25% NW TO 40-50% SE FRI. AN APPROACHING SHORTWAVE TROUGH... POTENT BUT SLOWLY WEAKENING... WILL DROP ESE THROUGH THE LOWER GREAT LAKES/OH VALLEY LATE FRI NIGHT... LIKELY LEADING TO CONTINUED PARTLY TO MOSTLY CLOUDY SKIES DOWNSTREAM OVER NC OVERNIGHT. THICKNESSES ARE PROJECTED TO BE NEAR NORMAL THU... WHICH WITH CONSIDERATION OF GOOD CONVECTIVE CLOUD COVERAGE WOULD SUPPORT HIGHS OF 86-92. THU NIGHT LOWS NOT FAR FROM NORMAL... 67-72. SLIGHTLY LESS WARMTH ON FRI WITH BELOW-NORMAL THICKNESSES POINTING TO HIGHS OF 86-90. FOR SAT-SUN: THE SURFACE TROUGH OVER ERN NC IS LIKELY TO DISSIPATE SAT AS IT IS OVERTAKEN BY THE ATLANTIC RIDGE BULGING WESTWARD... WITH FORMATION OF A NEW WEAK LEE TROUGH OVER THE PIEDMONT AND SOME ATTENDANT MINOR RECOVERY OF PW. THE AFOREMENTIONED WEAKENING MID LEVEL WAVE WILL CROSS THE MIDATLANTIC REGION SAT... ALTHOUGH MODEL DISPARITY EMERGES AS THE ECMWF IS SLOWER/STRONGER THAN THE GFS AND THEREFORE GENERATES MORE CONVECTION OVER CENTRAL/ERN NC. WILL RETAIN CHANCE POPS SAT... HIGHER EAST THAN WEST... GENERALLY FOLLOWING THE TYPICAL DIURNAL TREND. THE GFS DEPICTS FURTHER RECOVERY OF PW VALUES SUN WITH ANOTHER MINOR WAVE CROSSING THE REGION WITHIN VERY WEAK CYCLONIC FLOW AND A RETENTION OF THE PIEDMONT SURFACE TROUGH... AND WE SHOULD SEE YET ANOTHER ROUND OF MAINLY SCATTERED DIURNALLY-DRIVEN STORMS IN THE MID AFTERNOON INTO EARLY EVENING... WITH COVERAGE AND INTENSITY LIMITED BY THE WEAK DEEP LAYER SHEAR. FOR MON-TUE: THE GFE HAS COME INTO AGREEMENT WITH THE ECMWF`S SOLUTION (CONSISTENT OVER THE LAST FEW RUNS) REGARDING THE DEEPENING MID LEVEL VORTEX WHICH DRIFTS ACROSS THE GREAT LAKES/SE ONTARIO EARLY NEXT WEEK. THE PIEDMONT SURFACE TROUGH WILL SHARPEN AND PUSH A BIT TO THE SOUTHEAST IN RESPONSE TO THE APPROACHING SYNOPTIC COLD FRONT... EXPECTED TO PROGRESS SOUTHEAST TOWARD NW NC BY LATE TUE. PW REMAINS ABOVE NORMAL AREAWIDE MON... THEN THE HIGHER VALUES SHIFT TO OUR EAST TUE WITH THE SHIFTING TROUGH AND STRENGTHENING LOW AND MID LEVEL FLOW FROM THE WSW. WILL RETAIN CLIMATOLOGICALLY TYPICAL POPS MON (SLIGHTLY LOWER IN THE TRIAD AND HIGHER TO THE SOUTH/EAST... FOCUSED ON THE AFTERNOON INTO MID EVENING)... THEN TREND POPS BACK DOWN A TAD IN THE WEST TUE. THICKNESSES REBOUND BACK CLOSER TO NORMAL SO WILL NOT DEPART MUCH FROM SEASONAL NORMALS MON/TUE (WITH NORMAL HIGH/LOW OF 90/70 AT RDU AND 89/69 AT GSO). -GIH && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 155 PM TUESDAY... VFR CONDITIONS ARE EXPECTED THROUGHOUT MUCH OF THE 18Z VALID TAF PERIOD. AS MOISTURE INCREASES AGAIN OVER THE REGION FROM THE WEST...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS SHOULD OCCUR PARTICULARLY TOWARD THE TRIAD VERY LATE THIS AFTERNOON INTO THE EVENING. WITH UNCERTAINTY IN THE LOCATION OF ANY THUNDER ONLY INCLUDED A TEMPO FOR SHOWERS IN THE TAFS FOR KINT AND KGSO FROM ABOUT 23Z TO 04Z. ISOLATED SHOWERS OR SPRINKLES ARE POSSIBLE OVERNIGHT THEN CHANCES FOR SHOWERS INCREASE DURING WEDNESDAY WITH AT LEAST TEMPO CONDITIONS ANTICIPATED AROUND THE TRIAD DURING THE MORNING. SREF MODEL PROBABILITY OF IFR CONDITIONS ARE LOW BUT PROBABILITIES OF MVFR CONDITIONS ESPECIALLY OVER THE NORTHWEST PIEDMONT INCREASE AFTER 12Z WEDNESDAY AND HAVE INCLUDED SUCH CEILINGS IN THE TEMPO CONDITIONS AT KINT AND KGSO WEDNESDAY MORNING. GUSTY SOUTHWEST WINDS SHOULD DIMINISH BUT REMAIN NOTICEABLE OUT OF THE SOUTH TO SOUTHWEST OVERNIGHT...WITH A FEW GUSTS DEVELOPING MAINLY TOWARD KFAY WEDNESDAY MORNING WHERE HEATING TO START THE DAY SHOULD BE A LITTLE BETTER RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA. BEYOND THE 18Z VALID TAF PERIOD...AT LEAST SCATTERED SHOWERS AND THUNDERSTORMS...AND THEIR ASSOCIATED SUB-VFR CONDITIONS...CAN BE EXPECTED OVER CENTRAL NORTH CAROLINA AT LEAST INTO THE END OF THE WORK WEEK. A COLD FRONT WEAKENS AS IT APPROACHES THE STATE THURSDAY...BUT A SURFACE TROUGH THEN LINGERS AT LEAST THROUGH FRIDAY AND LIKELY INTO AT LEAST PART OF THE WEEKEND. COVERAGE OF PRECIPITATION OVER CENTRAL NORTH CAROLINA SHOULD BE GREATER THURSDAY AND FRIDAY AS COMPARED TO THE UPCOMING WEEKEND. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...WSS/DJF SHORT TERM...WSS LONG TERM...HARTFIELD AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
156 PM EDT TUE JUL 8 2014 .SYNOPSIS...BROAD HIGH PRESSURE WEAKENS AS A COLD FRONT MOVES TOWARD THE REGION FROM THE GREAT LAKES. THIS COLD FRONT SHOULD MOVE INTO THE MID-ATLANTIC WEDNESDAY...WEAKENING AS IT MOVES INTO NORTH CAROLINA THURSDAY. A TROUGH OF LOW PRESSURE THEN PERSISTS OVER THE REGION AT LEAST THROUGH FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 910 AM TUESDAY... THE LATEST SURFACE ANALYSIS SHOWED BROAD HIGH PRESSURE MOSTLY OVER THE MID-ATLANTIC AND THE CAROLINAS WITH A WEAK SURFACE TROUGH AMONG THE BROAD RIDGE OVER THE CENTRAL PIEDMONT. THE SPC MESOANALYSIS SHOWED A NOTICEABLE MINIMUM OF PRECIPITABLE WATER VALUES OVER THE WESTERN PART OF THE STATE...SIMILAR TO WHAT WAS FORECAST BY THE MONDAY GUIDANCE. THE RAP FORECASTS THIS MINIMUM TO MOVE ACROSS CENTRAL NORTH CAROLINA DURING THE DAY...AND FOR THE MOST PART RAP SOUNDINGS ARE SIMILAR TO SOUNDINGS FORECAST BY THE GFS MONDAY... QUITE STABLE TO DEEP CONVECTION DURING THE DAY. TWO CAVEATS TO THIS ARE CURRENTLY...AND VERY LATE TODAY. CURRENTLY...PRECIPITABLE WATER VALUES ARE AT OR ABOVE 1.5 INCHES OVER A LARGE PART OF CENTRAL NORTH CAROLINA...AND RAP SOUNDINGS SHOW THE PRESENCE OF MID-LEVEL INSTABILITY THAT WANES BY 18Z AS THE LOWER MOISTURE VALUES MOVE EAST. THE LATEST VISIBLE IMAGERY SHOWED A NARROW BAND OF MID-LEVEL CLOUDS THAT DEVELOPED FROM NEAR ROXBORO TO WADESBORO...AND THE HRRR WRF ACTUALLY FORECASTS A SHOWER OR TWO DEVELOPING FROM THIS. WATER VAPOR IMAGERY WOULD SUGGEST ENOUGH SUBSIDENCE TO PRECLUDE A SHOWER... BUT THE DEVELOPMENT OF THE CLOUDS PLUS THE PRESENCE OF WEAK INSTABILITY MAKES IT WORTHY OF NOTE HERE. LATE TODAY...THE RAP FORECASTS LIFT MOVING INTO THE FAR NORTHWEST PIEDMONT TOWARD KINT BY 23Z. RAP SOUNDINGS ARE STILL FAIRLY STABLE AT THAT POINT...AND QPF ON THE RAP IS NIL THROUGH 00Z WEDNESDAY. PRECIPITABLE WATER VALUES INCREASE QUICKLY ON THE RAP...TO NEAR 1.5 INCHES JUST AFTER 00Z WEDNESDAY...AS K INDICES RISE TO NEAR 40. LIKE THE GFS FORECAST MONDAY...MODEST MID-LEVEL COOLING COUPLED WITH MOISTURE ADVECTION MAY BE ENOUGH FOR A SHOWER OR THUNDERSTORM TO MOVE INTO THE WEST AND NORTHWEST PIEDMONT THIS EVENING. MOS GUIDANCE POPS ARE A FEW PERCENTAGE POINTS LOWER THAN THAT GUIDANCE OF MONDAY...AND WRF ARW GUIDANCE SUGGESTS LITTLE PRECIPITATION INTO THE EVENING. STILL...THE MOISTURE ADVECTION AND SLIGHT COOLING ALOFT... COUPLED WITH A WEAKENING MID-LEVEL SHORTWAVE MOVING INTO THE WESTERN PIEDMONT THIS EVENING...IS ENOUGH TO AT LEAST CONTINUE THE SMALL CHANCES WEST AS CURRENTLY FORECAST THIS EVENING...AND MAY NEED TO EXPAND SLIGHTLY FARTHER EAST. THE 00Z GFS APPEARED TO SUFFER FROM SOME MINOR CONVECTIVE FEEDBACK WHILE THE ECMWF HAS BEEN VERY CONSISTENT IN SUGGESTING THE BEST THREAT FOR OVERNIGHT CONVECTION TO OUR NW. IT SHOULD ALSO BE NOTED THAT THE CONVECTIVE ALLOWING MODELS VERIFIED WAY OVERDONE ACROSS THE OH VALLEY INTO THE MID ATLANTIC AT 06Z. HIGHS TODAY IN THE LOWER TO MID 90S. WARM OVERNIGHT WITH LOWS NEAR 70 TO THE LOWER 70S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 310 AM TUESDAY... MID LEVEL SHEAR AXIS ASSOCIATED WITH THE NORTHERN STREAM S/W AND ITS ATTENDANT SURFACE BOUNDARY WILL DRIFT SEWD INTO CENTRAL NC WEDNESDAY AFTERNOON-WEDNESDAY NIGHT. THIS SYSTEM WILL INTERACT WITH STRONG HEATING AND AVAILABLE MOISTURE (PRECIPITABLE WATER VALUES IN THE NEIGHBORHOOD OF 1.67-1.9 INCHES) TO INITIATE AND SUSTAIN SCATTERED CONVECTION...ESPECIALLY WEDNESDAY AFTERNOON-WEDNESDAY EVENING. SOME CONVECTIVE PARAMETERS SUGGEST SOME POTENTIAL FOR ORGANIZED CONVECTION IN THE FORM OF BROKEN CONVECTIVE SEGMENTS. IF THESE SEGMENTS WERE TO DEVELOP...COULD SEE A DAMAGING WIND THREAT WITH THE STRONGER CELLS. THIS THREAT APPEARS GREATEST ACROSS THE NORTHERN PIEDMONT INTO THE NORTHERN COASTAL PLAIN (GENERALLY NORTH OF I-40) WHERE BULK SHEAR VALUES APPROACH 30 KTS. DUE TO PRESENCE OF SHEAR AXIS AND SFC BOUNDARY...EXPECT SCATTERED CONVECTION TO PERSIST WELL INTO THE NIGHT THOUGH OVERALL COVERAGE AND INTENSITY WILL DIMINISH AS NEAR SURFACE AIR MASS UNDERGOES NOCTURNAL STABILIZATION. HIGH TEMPS WEDNESDAY DEPENDENT UPON AMOUNT OF INSOLATION AND CONVECTIVE COVERAGE. IF SUN LIMITED DUE TO EXTENSIVE CLOUD COVERAGE OR IF THE GFS IS CORRECT AND SCATTERED CONVECTION IS OCCURRING AT THE THE START OF THE DAY...THEN MAX TEMPS ACROSS THE NORTH COULD END UP BEING 5-6 DEGREES COOLER THAN FORECAST. DUE TO ANTICIPATED TIMING...BELIEVE THAT THE SOUTHERN HALF OF THE FORECAST AREA STANDS A GOOD SHOT OF SEEING TEMPS RETURNING TO THE MID 90S. MIN TEMPS WEDNESDAY NIGHT IN THE UPPER 60S TO AROUND 70 NORTH AND LOWER 70S SOUTH. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 310 AM TUESDAY... THURSDAY THROUGH FRIDAY: THURSDAY LOOKS TO BE THE MOST ACTIVE DAY OF THE FORECAST PERIOD AS AN APPROACHING MID LEVEL TROUGH WILL HELP TO SEND A WEAKENING COLD FRONT/SURFACE TROUGH SLOWLY ACROSS THE AREA. MODELS ARE IN GENERAL AGREEMENT IN SHOWING THE FRONT/SURFACE TROUGH LOCATED ACROSS CENTRAL NC DURING DURING PEAK HEATING THURSDAY. THE BEST MLCAPE AND MUCAPE IS EXPECTED TO BE LOCATED ACROSS THE SOUTHEASTERN HALF OF CENTRAL NC.... WHERE 800 TO 1200 J/KG MLCAPE IS EXPECTED... ALONG WITH UPWARDS OF 2000-2500 J/KG OF MUCAPE. THIS COMBINED WITH A MOIST AIR MASS CHARACTERIZED BY PW`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
AREA FORECAST DISCUSSION
NWS RALEIGH NC
911 AM EDT TUE JUL 8 2014 .SYNOPSIS...A WEAK SURFACE TROUGH WILL LINGER OVER THE PIEDMONT THROUGH WEDNESDAY. A SLOW MOVING COLD FRONT WILL SETTLE INTO THE CAROLINAS FROM THE NORTHWEST WEDNESDAY NIGHT AND THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 910 AM TUESDAY... THE LATEST SURFACE ANALYSIS SHOWED BROAD HIGH PRESSURE MOSTLY OVER THE MID-ATLANTIC AND THE CAROLINAS WITH A WEAK SURFACE TROUGH AMONG THE BROAD RIDGE OVER THE CENTRAL PIEDMONT. THE SPC MESOANALYSIS SHOWED A NOTICEABLE MINIMUM OF PRECIPITABLE WATER VALUES OVER THE WESTERN PART OF THE STATE...SIMILAR TO WHAT WAS FORECAST BY THE MONDAY GUIDANCE. THE RAP FORECASTS THIS MINIMUM TO MOVE ACROSS CENTRAL NORTH CAROLINA DURING THE DAY...AND FOR THE MOST PART RAP SOUNDINGS ARE SIMILAR TO SOUNDINGS FORECAST BY THE GFS MONDAY... QUITE STABLE TO DEEP CONVECTION DURING THE DAY. TWO CAVEATS TO THIS ARE CURRENTLY...AND VERY LATE TODAY. CURRENTLY...PRECIPITABLE WATER VALUES ARE AT OR ABOVE 1.5 INCHES OVER A LARGE PART OF CENTRAL NORTH CAROLINA...AND RAP SOUNDINGS SHOW THE PRESENCE OF MID-LEVEL INSTABILITY THAT WANES BY 18Z AS THE LOWER MOISTURE VALUES MOVE EAST. THE LATEST VISIBLE IMAGERY SHOWED A NARROW BAND OF MID-LEVEL CLOUDS THAT DEVELOPED FROM NEAR ROXBORO TO WADESBORO...AND THE HRRR WRF ACTUALLY FORECASTS A SHOWER OR TWO DEVELOPING FROM THIS. WATER VAPOR IMAGERY WOULD SUGGEST ENOUGH SUBSIDENCE TO PRECLUDE A SHOWER... BUT THE DEVELOPMENT OF THE CLOUDS PLUS THE PRESENCE OF WEAK INSTABILITY MAKES IT WORTHY OF NOTE HERE. LATE TODAY...THE RAP FORECASTS LIFT MOVING INTO THE FAR NORTHWEST PIEDMONT TOWARD KINT BY 23Z. RAP SOUNDINGS ARE STILL FAIRLY STABLE AT THAT POINT...AND QPF ON THE RAP IS NIL THROUGH 00Z WEDNESDAY. PRECIPITABLE WATER VALUES INCREASE QUICKLY ON THE RAP...TO NEAR 1.5 INCHES JUST AFTER 00Z WEDNESDAY...AS K INDICES RISE TO NEAR 40. LIKE THE GFS FORECAST MONDAY...MODEST MID-LEVEL COOLING COUPLED WITH MOISTURE ADVECTION MAY BE ENOUGH FOR A SHOWER OR THUNDERSTORM TO MOVE INTO THE WEST AND NORTHWEST PIEDMONT THIS EVENING. MOS GUIDANCE POPS ARE A FEW PERCENTAGE POINTS LOWER THAN THAT GUIDANCE OF MONDAY...AND WRF ARW GUIDANCE SUGGESTS LITTLE PRECIPITATION INTO THE EVENING. STILL...THE MOISTURE ADVECTION AND SLIGHT COOLING ALOFT... COUPLED WITH A WEAKENING MID-LEVEL SHORTWAVE MOVING INTO THE WESTERN PIEDMONT THIS EVENING...IS ENOUGH TO AT LEAST CONTINUE THE SMALL CHANCES WEST AS CURRENTLY FORECAST THIS EVENING...AND MAY NEED TO EXPAND SLIGHTLY FARTHER EAST. THE 00Z GFS APPEARED TO SUFFER FROM SOME MINOR CONVECTIVE FEEDBACK WHILE THE ECMWF HAS BEEN VERY CONSISTENT IN SUGGESTING THE BEST THREAT FOR OVERNIGHT CONVECTION TO OUR NW. IT SHOULD ALSO BE NOTED THAT THE CONVECTIVE ALLOWING MODELS VERIFIED WAY OVERDONE ACROSS THE OH VALLEY INTO THE MID ATLANTIC AT 06Z. HIGHS TODAY IN THE LOWER TO MID 90S. WARM OVERNIGHT WITH LOWS NEAR 70 TO THE LOWER 70S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 310 AM TUESDAY... MID LEVEL SHEAR AXIS ASSOCIATED WITH THE NORTHERN STREAM S/W AND ITS ATTENDANT SURFACE BOUNDARY WILL DRIFT SEWD INTO CENTRAL NC WEDNESDAY AFTERNOON-WEDNESDAY NIGHT. THIS SYSTEM WILL INTERACT WITH STRONG HEATING AND AVAILABLE MOISTURE (PRECIPITABLE WATER VALUES IN THE NEIGHBORHOOD OF 1.67-1.9 INCHES) TO INITIATE AND SUSTAIN SCATTERED CONVECTION...ESPECIALLY WEDNESDAY AFTERNOON-WEDNESDAY EVENING. SOME CONVECTIVE PARAMETERS SUGGEST SOME POTENTIAL FOR ORGANIZED CONVECTION IN THE FORM OF BROKEN CONVECTIVE SEGMENTS. IF THESE SEGMENTS WERE TO DEVELOP...COULD SEE A DAMAGING WIND THREAT WITH THE STRONGER CELLS. THIS THREAT APPEARS GREATEST ACROSS THE NORTHERN PIEDMONT INTO THE NORTHERN COASTAL PLAIN (GENERALLY NORTH OF I-40) WHERE BULK SHEAR VALUES APPROACH 30 KTS. DUE TO PRESENCE OF SHEAR AXIS AND SFC BOUNDARY...EXPECT SCATTERED CONVECTION TO PERSIST WELL INTO THE NIGHT THOUGH OVERALL COVERAGE AND INTENSITY WILL DIMINISH AS NEAR SURFACE AIR MASS UNDERGOES NOCTURNAL STABILIZATION. HIGH TEMPS WEDNESDAY DEPENDENT UPON AMOUNT OF INSOLATION AND CONVECTIVE COVERAGE. IF SUN LIMITED DUE TO EXTENSIVE CLOUD COVERAGE OR IF THE GFS IS CORRECT AND SCATTERED CONVECTION IS OCCURRING AT THE THE START OF THE DAY...THEN MAX TEMPS ACROSS THE NORTH COULD END UP BEING 5-6 DEGREES COOLER THAN FORECAST. DUE TO ANTICIPATED TIMING...BELIEVE THAT THE SOUTHERN HALF OF THE FORECAST AREA STANDS A GOOD SHOT OF SEEING TEMPS RETURNING TO THE MID 90S. MIN TEMPS WEDNESDAY NIGHT IN THE UPPER 60S TO AROUND 70 NORTH AND LOWER 70S SOUTH. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 310 AM TUESDAY... THURSDAY THROUGH FRIDAY: THURSDAY LOOKS TO BE THE MOST ACTIVE DAY OF THE FORECAST PERIOD AS AN APPROACHING MID LEVEL TROUGH WILL HELP TO SEND A WEAKENING COLD FRONT/SURFACE TROUGH SLOWLY ACROSS THE AREA. MODELS ARE IN GENERAL AGREEMENT IN SHOWING THE FRONT/SURFACE TROUGH LOCATED ACROSS CENTRAL NC DURING DURING PEAK HEATING THURSDAY. THE BEST MLCAPE AND MUCAPE IS EXPECTED TO BE LOCATED ACROSS THE SOUTHEASTERN HALF OF CENTRAL NC.... WHERE 800 TO 1200 J/KG MLCAPE IS EXPECTED... ALONG WITH UPWARDS OF 2000-2500 J/KG OF MUCAPE. THIS COMBINED WITH A MOIST AIR MASS CHARACTERIZED BY PW`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
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1056 PM EDT WED JUL 9 2014 .SYNOPSIS... HIGH PRESSURE OVER THE UPPER MIDWEST WILL MOVE EAST ACROSS THE GREAT LAKES ON THURSDAY AND BE LOCATED NEAR NEW YORK CITY BY SATURDAY MORNING. A WARM FRONT WILL BE MOVING NORTHEAST FROM THE LOWER OHIO VALLEY ON SATURDAY AS A COLD FRONT DROPS ACROSS THE WESTERN GREAT LAKES. THE TWO FRONTS WILL CONVERGE ON THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... SOME SHOWERS DEVELOPING ON THE LAKE. UPDATED THE GRIDS TO REFLECT THIS. SOME THUNDER IS ALSO POSSIBLE. AT THIS TIME EXPECTING IT TO STAY OVER THE WATER...THIS WILL HAVE TO BE WATCHED. COLD FRONT CONTINUING TO SAG SOUTH OF THE AREA THIS EVENING. SHOWERS ON THE DECREASE. SOME TROFINESS AND RIGHT REAR QUAD OF THE JET MAY KEEP SOME ISOLATED SHOWERS GOING TO AROUND MIDNIGHT MAINLY OVER THE SOUTHERN PORTION OF THE FORECAST AREA. SKIES WILL BE MOSTLY CLEAR TO PARTLY CLOUDY OVERNIGHT. THE MODELS HAVE PLENTY OF LOW LEVEL MOISTURE AROUND AND WITH THE UPPER TROF ACROSS THE AREA SOME CLOUDINESS WILL LINGER. THE HRRR MODEL TRIES TO DEVELOP SOME SHOWERS OVER THE LAKE TOWARD DAYBREAK. THIS MAY OCCUR BECAUSE OF THE WARM LAKE AND SOME CONVERGENCE. MADE ONLY MINOR ADJUSTMENTS TO THE LOWS. IF THE CLOUDS STAY PATCHY TEMPERATURES SHOULD CONTINUE TO DROP WITH THE LIGHT WINDS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/... SOME OF THE MODELS SHOW ONE LAST SHORT WAVE SLIDING THROUGH THE TROUGH ON THURSDAY MORNING. I SUPPOSE A SHOWER COULD SNEAK OFF THE LAKE ACROSS EXTREME NE OH/NW PA IN THE MORNING OR MIDDAY OTHERWISE THE DRY AIR AND SUBSIDENCE SHOULD WIN OUT. HIGHS IN THE 70S AGAIN. SUNNY FRIDAY WITH PERHAPS A FEW HIGH CLOUDS AND PERHAPS A FEW CUMULUS ACROSS NE OH/NW PA. HIGHS GENERALLY MID 70S TO LOWER 80S. MOST OF THE MODELS ARE HOLDING OFF ON THE SHOWERS FOR SATURDAY WHICH SEEMS REASONABLE AS THE SURFACE HIGH WILL JUST BE TO THE EAST AND THERE SHOULD BE PLENTY OF DRY AIR IN THE LOWER LAYERS. CANNOT RULE OUT A WARM ADVECTION SHOWER GETTING INTO NW OHIO. DEWPOINTS WILL START TO INCREASE BUT WILL LIKELY NOT GET INTO THE UNCOMFORTABLE RANGE YET. TEMPS SHOULD RECOVER TO NEAR NORMAL. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... MOST OF THE MODELS SHOW A SWATCH OF SHOWERS AND THUNDERSTORMS SPILLING ACROSS THE LOWER GREAT LAKES SATURDAY NIGHT AND ESPECIALLY ON SUNDAY AS A WARM FRONT PUSHES NORTH AND A COLD FRONT SAGS SOUTHEAST ACROSS THE GREAT LAKES. WE MAY NEED TO GO WITH HIGHER POPS BUT STILL NOT OVERLY CONFIDENT ABOUT THE TIMING. IF THERE IS A THUNDERSTORM COMPLEX AND IT MISSES THE AREA OR MOVES ACROSS THE AREA VERY QUICKLY THEN WE END UP WITH JUST A FEW SHOWERS. WILL JUST KEEP IT A CHANCE FOR NOW. SHOULD BE MORE HUMID BY SUNDAY BUT TEMPS ARE A LITTLE TRICKY DEPENDING ON THE AMOUNT OF CLOUDS AND SHOWERS. WILL SPLIT THE DIFFERENCE AND GO FOR HIGHS AROUND 80. COULD REACH THE LOWER/MID 80S WITH SOME SUNSHINE AND IT COULD STAY IN THE 70S WITH ENOUGH CLOUDS AND SHOWERS. UNSEASONABLY COOL AIR MASS FOR EARLY NEXT WEEK AS A PROMINENT TROUGH REMAINS NEARLY STATIONARY ACROSS THE GREAT LAKES. COLD FRONT COMES ACROSS MONDAY WITH SHOWERS/THUNDERSTORMS. THERE MAY BE SHOWERS THAT POP UP WITH SECONDARY TROUGHS TUESDAY AND WEDNESDAY...BUT QUESTION WILL BE HOW MUCH MOISTURE WILL BE AROUND. IF H8 TEMPS GET BELOW 8C OR SO AND WINDS SHIFT OUT OF THE NORTHWEST THE LAKE MAY HELP WITH THAT MOISTURE. TEMPERATURES WILL BE BELOW NORMAL AND BY MID WEEK TEMPS WILL BE ON EITHER SIDE OF 70 FOR HIGHS. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... SCATTERED SHOWERS ASSOCIATED WITH WEAK UPPER TROUGH WILL BEGIN TO DISSIPATE AFTER SUNSET. LIGHT AND VARIABLE WINDS THIS EVENING ASSOCIATED WITH WEAK MESO LOW BETWEEN FDY AND MFD. AHEAD OF THE LOW WINDS TURN TO THE S-SE...THEN BEHIND THE LOW WINDS TURN TO THE N-NW. WINDS WILL GRADUALLY TURN TO THE NORTH LATE THIS EVENING AS LOW MOVES EAST OF AREA. OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY IN THUNDERSTORMS. && .MARINE... ONE LAST TROUGH TO CROSS THE LAKE EARLY THIS EVENING THEN HIGH PRESSURE MOVES OVERHEAD FOR THURSDAY. SO LIGHT WEST-NORTHWEST WINDS WILL BECOME LIGHT/VARIABLE TONIGHT. THE HIGH SHIFTS EAST FRIDAY AND A LIGHT SOUTHERLY FLOW RESULTS. SHOWERS/THUNDERSTORMS ENTER THE FORECAST SATURDAY NIGHT AND SUNDAY AS THE ATMOSPHERE BECOMES MORE UNSTABLE AHEAD OF THE NEXT SYSTEM. THE COLD FRONT WILL CROSS THE LAKE ON MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KOSARIK NEAR TERM...KIELTYKA SHORT TERM...KOSARIK LONG TERM...KOSARIK/OUDEMAN AVIATION...DJB MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
937 PM EDT WED JUL 9 2014 .SYNOPSIS... HIGH PRESSURE OVER THE UPPER MIDWEST WILL MOVE EAST ACROSS THE GREAT LAKES ON THURSDAY AND BE LOCATED NEAR NEW YORK CITY BY SATURDAY MORNING. A WARM FRONT WILL BE MOVING NORTHEAST FROM THE LOWER OHIO VALLEY ON SATURDAY AS A COLD FRONT DROPS ACROSS THE WESTERN GREAT LAKES. THE TWO FRONTS WILL CONVERGE ON THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... COLD FRONT CONTINUING TO SAG SOUTH OF THE AREA THIS EVENING. SHOWERS ON THE DECREASE. SOME TROFINESS AND RIGHT REAR QUAD OF THE JET MAY KEEP SOME ISOLATED SHOWERS GOING TO AROUND MIDNIGHT MAINLY OVER THE SOUTHERN PORTION OF THE FORECAST AREA. SKIES WILL BE MOSTLY CLEAR TO PARTLY CLOUDY OVERNIGHT. THE MODELS HAVE PLENTY OF LOW LEVEL MOISTURE AROUND AND WITH THE UPPER TROF ACROSS THE AREA SOME CLOUDINESS WILL LINGER. THE HRRR MODEL TRIES TO DEVELOP SOME SHOWERS OVER THE LAKE TOWARD DAYBREAK. THIS MAY OCCUR BECAUSE OF THE WARM LAKE AND SOME CONVERGENCE. MADE ONLY MINOR ADJUSTMENTS TO THE LOWS. IF THE CLOUDS STAY PATCHY TEMPERATURES SHOULD CONTINUE TO DROP WITH THE LIGHT WINDS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/... SOME OF THE MODELS SHOW ONE LAST SHORT WAVE SLIDING THROUGH THE TROUGH ON THURSDAY MORNING. I SUPPOSE A SHOWER COULD SNEAK OFF THE LAKE ACROSS EXTREME NE OH/NW PA IN THE MORNING OR MIDDAY OTHERWISE THE DRY AIR AND SUBSIDENCE SHOULD WIN OUT. HIGHS IN THE 70S AGAIN. SUNNY FRIDAY WITH PERHAPS A FEW HIGH CLOUDS AND PERHAPS A FEW CUMULUS ACROSS NE OH/NW PA. HIGHS GENERALLY MID 70S TO LOWER 80S. MOST OF THE MODELS ARE HOLDING OFF ON THE SHOWERS FOR SATURDAY WHICH SEEMS REASONABLE AS THE SURFACE HIGH WILL JUST BE TO THE EAST AND THERE SHOULD BE PLENTY OF DRY AIR IN THE LOWER LAYERS. CANNOT RULE OUT A WARM ADVECTION SHOWER GETTING INTO NW OHIO. DEWPOINTS WILL START TO INCREASE BUT WILL LIKELY NOT GET INTO THE UNCOMFORTABLE RANGE YET. TEMPS SHOULD RECOVER TO NEAR NORMAL. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... MOST OF THE MODELS SHOW A SWATCH OF SHOWERS AND THUNDERSTORMS SPILLING ACROSS THE LOWER GREAT LAKES SATURDAY NIGHT AND ESPECIALLY ON SUNDAY AS A WARM FRONT PUSHES NORTH AND A COLD FRONT SAGS SOUTHEAST ACROSS THE GREAT LAKES. WE MAY NEED TO GO WITH HIGHER POPS BUT STILL NOT OVERLY CONFIDENT ABOUT THE TIMING. IF THERE IS A THUNDERSTORM COMPLEX AND IT MISSES THE AREA OR MOVES ACROSS THE AREA VERY QUICKLY THEN WE END UP WITH JUST A FEW SHOWERS. WILL JUST KEEP IT A CHANCE FOR NOW. SHOULD BE MORE HUMID BY SUNDAY BUT TEMPS ARE A LITTLE TRICKY DEPENDING ON THE AMOUNT OF CLOUDS AND SHOWERS. WILL SPLIT THE DIFFERENCE AND GO FOR HIGHS AROUND 80. COULD REACH THE LOWER/MID 80S WITH SOME SUNSHINE AND IT COULD STAY IN THE 70S WITH ENOUGH CLOUDS AND SHOWERS. UNSEASONABLY COOL AIR MASS FOR EARLY NEXT WEEK AS A PROMINENT TROUGH REMAINS NEARLY STATIONARY ACROSS THE GREAT LAKES. COLD FRONT COMES ACROSS MONDAY WITH SHOWERS/THUNDERSTORMS. THERE MAY BE SHOWERS THAT POP UP WITH SECONDARY TROUGHS TUESDAY AND WEDNESDAY...BUT QUESTION WILL BE HOW MUCH MOISTURE WILL BE AROUND. IF H8 TEMPS GET BELOW 8C OR SO AND WINDS SHIFT OUT OF THE NORTHWEST THE LAKE MAY HELP WITH THAT MOISTURE. TEMPERATURES WILL BE BELOW NORMAL AND BY MID WEEK TEMPS WILL BE ON EITHER SIDE OF 70 FOR HIGHS. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... SCATTERED SHOWERS ASSOCIATED WITH WEAK UPPER TROUGH WILL BEGIN TO DISSIPATE AFTER SUNSET. LIGHT AND VARIABLE WINDS THIS EVENING ASSOCIATED WITH WEAK MESO LOW BETWEEN FDY AND MFD. AHEAD OF THE LOW WINDS TURN TO THE S-SE...THEN BEHIND THE LOW WINDS TURN TO THE N-NW. WINDS WILL GRADUALLY TURN TO THE NORTH LATE THIS EVENING AS LOW MOVES EAST OF AREA. OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY IN THUNDERSTORMS. && .MARINE... ONE LAST TROUGH TO CROSS THE LAKE EARLY THIS EVENING THEN HIGH PRESSURE MOVES OVERHEAD FOR THURSDAY. SO LIGHT WEST-NORTHWEST WINDS WILL BECOME LIGHT/VARIABLE TONIGHT. THE HIGH SHIFTS EAST FRIDAY AND A LIGHT SOUTHERLY FLOW RESULTS. SHOWERS/THUNDERSTORMS ENTER THE FORECAST SATURDAY NIGHT AND SUNDAY AS THE ATMOSPHERE BECOMES MORE UNSTABLE AHEAD OF THE NEXT SYSTEM. THE COLD FRONT WILL CROSS THE LAKE ON MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KOSARIK NEAR TERM...KIELTYKA SHORT TERM...KOSARIK LONG TERM...KOSARIK/OUDEMAN AVIATION...DJB MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
157 PM EDT TUE JUL 8 2014 .SYNOPSIS... UNSETTLED WEATHER CONTINUES THROUGH EARLY WEDNESDAY AS A SERIES OF SYSTEMS PUSH EAST. HIGH PRESSURE BRINGS DRIER AIR TO THE REGION FOR THE END OF THE WEEK. ANOTHER SYSTEM OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... SLOWED THE POPS WITH LIKELIES AFTER 17Z. MAIN PORTION OF THE LEFTOVER MCS DRIFTED NORTHEAST AND MISSED OUR AREA FOR THE MOST PART. WILL BE WAITING FOR CLOUDS TO DISSIPATE...AND THEN EXPECT PERCOLATION THIS AFTERNOON. PREVIOUS DISCUSSION... CUT BACK POP CHCS FOR THE EARLY MORNING HOURS AS OVERNIGHT CONVECTION DIED OFF RAPIDLY WITH THE LOSS OF DAYTIME HEATING. NEAR TERM HI-RES MODELS RUC13 AND HRRR ARE IN FAIR AGREEMENT IN TRANSITIONING ANOTHER CONVECTIVE BAND ACROSS THE FORECAST AREA THIS AFTERNOON. MAIN FLY IN THE OINTMENT IS TRANSITION OF DYING MCS OVER WESTERN ILLINOIS THAT SLIDING TO THE EAST-NORTHEAST AND SHOULD ARRIVE IN CENTRAL OH BY AROUND 15Z. EXPECT MAINLY RESIDUAL SHOWERS AT THIS TIME AND BOUNCED POPS BACK INTO CHC CATEGORY FOR SE OH TO ACCOUNT FOR THIS FEATURE. AFOREMENTIONED CONVECTIVE BAND MAY HAVE SOME TROUBLE DEVELOPING IN POST MCS ENVIRONMENT THIS AFTERNOON...BUT ONCE IT GETS GOING...IT SHOULD MAKE A LITTLE MORE HEADWAY INTO THE CWA AS COMPARED TO PREVIOUS BAND FROM YESTERDAY. LONGWAVE TROUGH OVER THE EASTERN US UNDERGOING AMPLIFICATION... WITH 5H FALLS OVER RLX AREA..AND MID LEVEL FLOW BECOMING MORE CYCLONIC. EXPECT A BETTER CHANCE FOR SVR STORMS TODAY UNDER A MODERATELY UNSTABLE ATMOSPHERE AND BETTER SHEAR ENVIRONMENT. MAIN THREAT WILL BE GUSTY WINDS WITH LINE OF STORMS...AND SOME BOWING LINE SEGMENTS. STORMS WILL ALSO BE EFFICIENT PRECIP PRODUCERS WITH PWATS RUNNING 1.5 TO 2.0 INCHES LATER THIS AFTERNOON. KEPT MENTION OF LOCALLY HEAVY DOWNPOURS. WITH THE RECENT DRY CONDITIONS DO NOT SEE WIDESPREAD WATER PROBLEMS. HOWEVER...HEAVY DOWNPOURS COULD CAUSE LOCAL WATER PROBLEMS IF ANY REPETITIVE SHOWERS OCCUR. USED A BLEND OF BIAS CORRECTED DATA WITH PREVIOUS OFFICIAL FORECAST FOR TEMPS WHICH YIELDED A MINOR TWEAK TO THE TEMP FIELDS. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... NAM/GFS/ECMWF/CMC MODELS IN AGREEMENT IN THEIR QPF FIELDS PUSHING LAST RAIN SHOWERS OR THUNDERSTORMS TO THE EASTERN MOUNTAINS... MAINLY ACROSS THE SOUTH EARLY WEDNESDAY MORNING. THIS PCPN ACTIVITY IS ASSOCIATED WITH A SECOND COLD FRONT ENHANCED BY A H5 VORTICITY MAXIMA SINKING SOUTHEAST ACROSS THE AREA. BUFKIT SOUNDINGS INDICATE VERY DRY AIR ALOFT BEHIND THIS FRONT. YET ANOTHER H5 VORTICITY MAXIMA MOVES FROM THE NORTHWEST REACHING OUR EXTREME SOUTHEAST COUNTIES WEDNESDAY AFTERNOON. THEREFORE...DECIDED TO KEEP CHANCE POPS UNTIL THEN BEFORE ENDING ALL BY 00Z THURSDAY. TEMPERATURES WILL DEPEND ON THE DURATION OF CLOUD COVER ESPECIALLY WEDNESDAY AND THURSDAY. GENERALLY STAYED IN THE MID 80S LOWLANDS FOR WEDNESDAY...AND FEW DEGREES COOLER THURSDAY AS FLOW TURNS NORTHWEST TO NORTH BY THE AFTERNOON AND EVENING HOURS. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... USED A BLEND OF THE GFS AND ECMWF FOR FRIDAY. THIS LEAVES THE AREA UNDER A HIGH PRESSURE SYSTEM...BUT A BIT OF MOISTURE REMAINS IN THE NORTHERN MOUNTAINS....SO CAN NOT RULE OUT A THUNDERSTORM. FOR SATURDAY THROUGH MONDAY...SWITCHED TO A BLEND OF THE GFS/GEFS ENSEMBLE MEAN AND ECMWF ENSEMBLE MEAN. THIS BRINGS A SYSTEM INTO THE CENTRAL APPALACHIANS OVER THE WEEKEND...LINGERING INTO MONDAY. && .AVIATION /17Z TUESDAY THROUGH SATURDAY/... LINE OF CONVECTION HAS DEVELOPED QUICKLY AND WILL BE CROSSING THE OHIO RIVER SOON. CKB...EKN...AND PKB ARE IN A SEVERE THUNDERSTORM WATCH...PRIMARILY FOR WIND...BUT AS OF RIGHT NOW WITH THE APPROACHING LINE...WINDS ALOFT ARE PARALLEL TO THE LINE AS IT MOVES TO THE EAST. THIS WILL HAMPER THE WIND GUSTS SOMEWHAT...SO WILL KEEP TAF GUSTS BELOW 40KTS. TIMING THE LINE IS USUALLY TRICKY...AND THIS IS NO EXCEPTION. TEMPOS WERE A NECESSITY TODAY BECAUSE OF THIS...BUT WORKED TO KEEP THEM UNDER 2 HOURS. MAY GET SOME REDEVELOPMENT LATER THIS AFTERNOON/EVENING...BUT THE THREAT FOR ISOLATED SHOWERS AND STORMS WILL RETURN. WINDS WILL GUST OUT OF THE SOUTHWEST TO 25KTS. THERE WILL BE A FRONTAL PASSAGE IN THE NEXT TWO HOURS...BUT THE WIND SHIFT WILL BE MINIMAL TO NONE...AND IT SHOULD NOT AFFECT VELOCITIES AS MUCH AS THE LINE OF STORMS. GETTING INTO TONIGHT BECOMES CHALLENGING AS WELL. LOCALES RECEIVING RAIN...AS TYPICAL...WILL HAVE A BETTER SHOT AT FOG...ALTHOUGH IT APPEARS THE WIND MAY TRY TO STAY ABOVE CALM. THIS WILL MAKE FOG/MIST DEVELOPMENT QUESTIONABLE...BUT THE SYNOPTIC WIND MAY BE TRUMPED BY MESO HIGH AIR FROM CONVECTION EARLIER IN THE PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY... FORECAST CONFIDENCE: LOW TO MEDIUM. ALTERNATE SCENARIOS: CONFIDENCE IS HIGH WITH THE CONVECTIVE OCCURRENCES...JUST NOT THE TIMING AS MUCH. FOG/MIST TONIGHT IS ALSO IN QUESTION. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H M HTS CONSISTENCY H H H H H H H H H H H M BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H M PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z WEDNESDAY... LOCAL IFR IN SHOWERS AND THUNDERSTORMS THROUGH EARLY WEDNESDAY... WITH LINGERING IFR CIGS POSSIBLE THROUGH LATE WEDNESDAY MORNING PARTICULARLY ACROSS HIGHER TERRAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KMC/ARJ NEAR TERM...KMC/26 SHORT TERM...ARJ LONG TERM...RPY AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1040 AM EDT TUE JUL 8 2014 .SYNOPSIS... UNSETTLED WEATHER CONTINUES THROUGH EARLY WEDNESDAY AS A SERIES OF SYSTEMS PUSH EAST. HIGH PRESSURE BRINGS DRIER AIR TO THE REGION FOR THE END OF THE WEEK. ANOTHER SYSTEM OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... SLOWED THE POPS WITH LIKELIES AFTER 17Z. MAIN PORTION OF THE LEFTOVER MCS DRIFTED NORTHEAST AND MISSED OUR AREA FOR THE MOST PART. WILL BE WAITING FOR CLOUDS TO DISSIPATE...AND THEN EXPECT PERCOLATION THIS AFTERNOON. PREVIOUS DISCUSSION... CUT BACK POP CHCS FOR THE EARLY MORNING HOURS AS OVERNIGHT CONVECTION DIED OFF RAPIDLY WITH THE LOSS OF DAYTIME HEATING. NEAR TERM HI-RES MODELS RUC13 AND HRRR ARE IN FAIR AGREEMENT IN TRANSITIONING ANOTHER CONVECTIVE BAND ACROSS THE FORECAST AREA THIS AFTERNOON. MAIN FLY IN THE OINTMENT IS TRANSITION OF DYING MCS OVER WESTERN ILLINOIS THAT SLIDING TO THE EAST-NORTHEAST AND SHOULD ARRIVE IN CENTRAL OH BY AROUND 15Z. EXPECT MAINLY RESIDUAL SHOWERS AT THIS TIME AND BOUNCED POPS BACK INTO CHC CATEGORY FOR SE OH TO ACCOUNT FOR THIS FEATURE. AFOREMENTIONED CONVECTIVE BAND MAY HAVE SOME TROUBLE DEVELOPING IN POST MCS ENVIRONMENT THIS AFTERNOON...BUT ONCE IT GETS GOING...IT SHOULD MAKE A LITTLE MORE HEADWAY INTO THE CWA AS COMPARED TO PREVIOUS BAND FROM YESTERDAY. LONGWAVE TROUGH OVER THE EASTERN US UNDERGOING AMPLIFICATION... WITH 5H FALLS OVER RLX AREA..AND MID LEVEL FLOW BECOMING MORE CYCLONIC. EXPECT A BETTER CHANCE FOR SVR STORMS TODAY UNDER A MODERATELY UNSTABLE ATMOSPHERE AND BETTER SHEAR ENVIRONMENT. MAIN THREAT WILL BE GUSTY WINDS WITH LINE OF STORMS...AND SOME BOWING LINE SEGMENTS. STORMS WILL ALSO BE EFFICIENT PRECIP PRODUCERS WITH PWATS RUNNING 1.5 TO 2.0 INCHES LATER THIS AFTERNOON. KEPT MENTION OF LOCALLY HEAVY DOWNPOURS. WITH THE RECENT DRY CONDITIONS DO NOT SEE WIDESPREAD WATER PROBLEMS. HOWEVER...HEAVY DOWNPOURS COULD CAUSE LOCAL WATER PROBLEMS IF ANY REPETITIVE SHOWERS OCCUR. USED A BLEND OF BIAS CORRECTED DATA WITH PREVIOUS OFFICIAL FORECAST FOR TEMPS WHICH YIELDED A MINOR TWEAK TO THE TEMP FIELDS. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... NAM/GFS/ECMWF/CMC MODELS IN AGREEMENT IN THEIR QPF FIELDS PUSHING LAST RAIN SHOWERS OR THUNDERSTORMS TO THE EASTERN MOUNTAINS... MAINLY ACROSS THE SOUTH EARLY WEDNESDAY MORNING. THIS PCPN ACTIVITY IS ASSOCIATED WITH A SECOND COLD FRONT ENHANCED BY A H5 VORTICITY MAXIMA SINKING SOUTHEAST ACROSS THE AREA. BUFKIT SOUNDINGS INDICATE VERY DRY AIR ALOFT BEHIND THIS FRONT. YET ANOTHER H5 VORTICITY MAXIMA MOVES FROM THE NORTHWEST REACHING OUR EXTREME SOUTHEAST COUNTIES WEDNESDAY AFTERNOON. THEREFORE...DECIDED TO KEEP CHANCE POPS UNTIL THEN BEFORE ENDING ALL BY 00Z THURSDAY. TEMPERATURES WILL DEPEND ON THE DURATION OF CLOUD COVER ESPECIALLY WEDNESDAY AND THURSDAY. GENERALLY STAYED IN THE MID 80S LOWLANDS FOR WEDNESDAY...AND FEW DEGREES COOLER THURSDAY AS FLOW TURNS NORTHWEST TO NORTH BY THE AFTERNOON AND EVENING HOURS. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... USED A BLEND OF THE GFS AND ECMWF FOR FRIDAY. THIS LEAVES THE AREA UNDER A HIGH PRESSURE SYSTEM...BUT A BIT OF MOISTURE REMAINS IN THE NORTHERN MOUNTAINS....SO CAN NOT RULE OUT A THUNDERSTORM. FOR SATURDAY THROUGH MONDAY...SWITCHED TO A BLEND OF THE GFS/GEFS ENSEMBLE MEAN AND ECMWF ENSEMBLE MEAN. THIS BRINGS A SYSTEM INTO THE CENTRAL APPALACHIANS OVER THE WEEKEND...LINGERING INTO MONDAY. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... VFR EXPECTED EARLY THIS MORNING. HOWEVER CLOUDS AND SCATTERED CONVECTION WILL BE ON THE INCREASE FROM THE WEST THROUGH ABOUT 16Z. CONVECTION BECOMES MORE WIDESPREAD AFT 16Z AS LINE OF THUNDERSTORMS ARRIVE FROM THE WEST. EXPECT GUSTY WINDS TO ACCOMPANY CONVECTION...ESPECIALLY AFTER 20Z AS NORTH-SOUTH BAND TRAVERSES ACROSS THE FORECAST AREA. EXPECT AT LEAST MVFR CONDITIONS WITH GUSTY WINDS AS BAND PASSES. LOCAL IFR CONDITIONS CAN BE EXPECTED INVOF HEAVIER PRECIPITATION CORES. STORM COVERAGE SHOULD GRADUALLY DECREASE IN COVERAGE ACROSS THE FAR NORTH...SOUTHEAST OHIO...TOWARDS END OF TAF PERIOD. INTRODUCED SOME FOG DEVELOPMENT IN ELEVATED RIVER VALLEYS LATE WEDNESDAY MORNING AS GRADIENTS SLACKEN. BOUNDARY LAYER SHOULD BE PRETTY MOIST FROM PREVIOUS DAYS CONVECTION TO ALLOW FOR MOSTLY MVFR FOG...WITH IFR CONDITIONS AT KEKN FOR A SHORT TIME PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: MORE WIDESPREAD IFR CONDITIONS DUE TO CONVECTION T0DAY. TIMING AND DENSITY OF FOG DEVELOPMENT WEDNESDAY MORNING MAY VARY CONSIDERABLY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21 CRW CONSISTENCY H H H H H H H M M M M M HTS CONSISTENCY H H H H H H H M M M H M BKW CONSISTENCY H H H H H H H H H H H M EKN CONSISTENCY H H H H H H H H H M M H PKB CONSISTENCY H H H H H H H M M H H H CKB CONSISTENCY H H H H H H H M M M M H AFTER 12Z WEDNESDAY... LOCAL IFR IN SHOWERS AND THUNDERSTORMS THROUGH EARLY WEDNESDAY... WITH LINGERING IFR CIGS POSSIBLE THROUGH LATE WEDNESDAY MORNING PARTICULARLY ACROSS HIGHER TERRAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KMC/ARJ NEAR TERM...KMC/26 SHORT TERM...ARJ LONG TERM...RPY AVIATION...KMC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
613 AM EDT TUE JUL 8 2014 .SYNOPSIS... UNSETTLED WEATHER CONTINUES THROUGH EARLY WEDNESDAY AS A SERIES OF SYSTEMS PUSH EAST. HIGH PRESSURE BRINGS DRIER AIR TO THE REGION FOR THE END OF THE WEEK. ANOTHER SYSTEM OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... MADE SOME MINOR TWEAKS TO POPS FOR EARLY THIS MORNING. OTHERWISE NO CHANGES. PREVIOUS DISCUSSION... CUT BACK POP CHCS FOR THE EARLY MORNING HOURS AS OVERNIGHT CONVECTION DIED OFF RAPIDLY WITH THE LOSS OF DAYTIME HEATING. NEAR TERM HI-RES MODELS RUC13 AND HRRR ARE IN FAIR AGREEMENT IN TRANSITIONING ANOTHER CONVECTIVE BAND ACROSS THE FORECAST AREA THIS AFTERNOON. MAIN FLY IN THE OINTMENT IS TRANSITION OF DYING MCS OVER WESTERN ILLINOIS THAT SLIDING TO THE EAST-NORTHEAST AND SHOULD ARRIVE IN CENTRAL OH BY AROUND 15Z. EXPECT MAINLY RESIDUAL SHOWERS AT THIS TIME AND BOUNCED POPS BACK INTO CHC CATEGORY FOR SE OH TO ACCOUNT FOR THIS FEATURE. AFOREMENTIONED CONVECTIVE BAND MAY HAVE SOME TROUBLE DEVELOPING IN POST MCS ENVIRONMENT THIS AFTERNOON...BUT ONCE IT GETS GOING...IT SHOULD MAKE A LITTLE MORE HEADWAY INTO THE CWA AS COMPARED TO PREVIOUS BAND FROM YESTERDAY. LONGWAVE TROUGH OVER THE EASTERN US UNDERGOING AMPLIFICATION... WITH 5H FALLS OVER RLX AREA..AND MID LEVEL FLOW BECOMING MORE CYCLONIC. EXPECT A BETTER CHANCE FOR SVR STORMS TODAY UNDER A MODERATELY UNSTABLE ATMOSPHERE AND BETTER SHEAR ENVIRONMENT. MAIN THREAT WILL BE GUSTY WINDS WITH LINE OF STORMS...AND SOME BOWING LINE SEGMENTS. STORMS WILL ALSO BE EFFICIENT PRECIP PRODUCERS WITH PWATS RUNNING 1.5 TO 2.0 INCHES LATER THIS AFTERNOON. KEPT MENTION OF LOCALLY HEAVY DOWNPOURS. WITH THE RECENT DRY CONDITIONS DO NOT SEE WIDESPREAD WATER PROBLEMS. HOWEVER...HEAVY DOWNPOURS COULD CAUSE LOCAL WATER PROBLEMS IF ANY REPETITIVE SHOWERS OCCUR. USED A BLEND OF BIAS CORRECTED DATA WITH PREVIOUS OFFICIAL FORECAST FOR TEMPS WHICH YIELDED A MINOR TWEAK TO THE TEMP FIELDS. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... NAM/GFS/ECMWF/CMC MODELS IN AGREEMENT IN THEIR QPF FIELDS PUSHING LAST RAIN SHOWERS OR THUNDERSTORMS TO THE EASTERN MOUNTAINS... MAINLY ACROSS THE SOUTH EARLY WEDNESDAY MORNING. THIS PCPN ACTIVITY IS ASSOCIATED WITH A SECOND COLD FRONT ENHANCED BY A H5 VORTICITY MAXIMA SINKING SOUTHEAST ACROSS THE AREA. BUFKIT SOUNDINGS INDICATE VERY DRY AIR ALOFT BEHIND THIS FRONT. YET ANOTHER H5 VORTICITY MAXIMA MOVES FROM THE NORTHWEST REACHING OUR EXTREME SOUTHEAST COUNTIES WEDNESDAY AFTERNOON. THEREFORE...DECIDED TO KEEP CHANCE POPS UNTIL THEN BEFORE ENDING ALL BY 00Z THURSDAY. TEMPERATURES WILL DEPEND ON THE DURATION OF CLOUD COVER ESPECIALLY WEDNESDAY AND THURSDAY. GENERALLY STAYED IN THE MID 80S LOWLANDS FOR WEDNESDAY...AND FEW DEGREES COOLER THURSDAY AS FLOW TURNS NORTHWEST TO NORTH BY THE AFTERNOON AND EVENING HOURS. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... USED A BLEND OF THE GFS AND ECMWF FOR FRIDAY. THIS LEAVES THE AREA UNDER A HIGH PRESSURE SYSTEM...BUT A BIT OF MOISTURE REMAINS IN THE NORTHERN MOUNTAINS....SO CAN NOT RULE OUT A THUNDERSTORM. FOR SATURDAY THROUGH MONDAY...SWITCHED TO A BLEND OF THE GFS/GEFS ENSEMBLE MEAN AND ECMWF ENSEMBLE MEAN. THIS BRINGS A SYSTEM INTO THE CENTRAL APPALACHIANS OVER THE WEEKEND...LINGERING INTO MONDAY. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... VFR EXPECTED EARLY THIS MORNING. HOWEVER CLOUDS AND SCATTERED CONVECTION WILL BE ON THE INCREASE FROM THE WEST THROUGH ABOUT 16Z. CONVECTION BECOMES MORE WIDESPREAD AFT 16Z AS LINE OF THUNDERSTORMS ARRIVE FROM THE WEST. EXPECT GUSTY WINDS TO ACCOMPANY CONVECTION...ESPECIALLY AFTER 20Z AS NORTH-SOUTH BAND TRAVERSES ACROSS THE FORECAST AREA. EXPECT AT LEAST MVFR CONDITIONS WITH GUSTY WINDS AS BAND PASSES. LOCAL IFR CONDITIONS CAN BE EXPECTED INVOF HEAVIER PRECIPITATION CORES. STORM COVERAGE SHOULD GRADUALLY DECREASE IN COVERAGE ACROSS THE FAR NORTH...SOUTHEAST OHIO...TOWARDS END OF TAF PERIOD. INTRODUCED SOME FOG DEVELOPMENT IN ELEVATED RIVER VALLEYS LATE WEDNESDAY MORNING AS GRADIENTS SLACKEN. BOUNDARY LAYER SHOULD BE PRETTY MOIST FROM PREVIOUS DAYS CONVECTION TO ALLOW FOR MOSTLY MVFR FOG...WITH IFR CONDITIONS AT KEKN FOR A SHORT TIME PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: MORE WIDESPREAD IFR CONDITIONS DUE TO CONVECTION T0DAY. TIMING AND DENSITY OF FOG DEVELOPMENT WEDNESDAY MORNING MAY VARY CONSIDERABLY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18 CRW CONSISTENCY H H H H H H H H H H M M HTS CONSISTENCY H H H H H H H H H H M M BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H M M CKB CONSISTENCY H H H H H H H H H H M M AFTER 12Z WEDNESDAY... LOCAL IFR IN SHOWERS AND THUNDERSTORMS THROUGH EARLY WEDNESDAY... WITH LINGERING IFR CIGS POSSIBLE THROUGH LATE WEDNESDAY MORNING PARTICULARLY ACROSS HIGHER TERRAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KMC/ARJ NEAR TERM...KMC SHORT TERM...ARJ LONG TERM...RPY AVIATION...KMC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
415 AM EDT TUE JUL 8 2014 .SYNOPSIS... UNSETTLED WEATHER CONTINUES THROUGH EARLY WEDNESDAY AS A SERIES OF SYSTEMS PUSH EAST. HIGH PRESSURE BRINGS DRIER AIR TO THE REGION FOR THE END OF THE WEEK. ANOTHER SYSTEM OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... CUT BACK POP CHCS FOR THE EARLY MORNING HOURS AS OVERNIGHT CONVECTION DIED OFF RAPIDLY WITH THE LOSS OF DAYTIME HEATING. NEAR TERM HI-RES MODELS RUC13 AND HRRR ARE IN FAIR AGREEMENT IN TRANSITIONING ANOTHER CONVECTIVE BAND ACROSS THE FORECAST AREA THIS AFTERNOON. MAIN FLY IN THE OINTMENT IS TRANSITION OF DYING MCS OVER WESTERN ILLINOIS THAT SLIDING TO THE EAST-NORTHEAST AND SHOULD ARRIVE IN CENTRAL OH BY AROUND 15Z. EXPECT MAINLY RESIDUAL SHOWERS AT THIS TIME AND BOUNCED POPS BACK INTO CHC CATEGORY FOR SE OH TO ACCOUNT FOR THIS FEATURE. AFOREMENTIONED CONVECTIVE BAND MAY HAVE SOME TROUBLE DEVELOPING IN POST MCS ENVIRONMENT THIS AFTERNOON...BUT ONCE IT GETS GOING...IT SHOULD MAKE A LITTLE MORE HEADWAY INTO THE CWA AS COMPARED TO PREVIOUS BAND FROM YESTERDAY. LONGWAVE TROUGH OVER THE EASTERN US UNDERGOING AMPLIFICATION... WITH 5H FALLS OVER RLX AREA..AND MID LEVEL FLOW BECOMING MORE CYCLONIC. EXPECT A BETTER CHANCE FOR SVR STORMS TODAY UNDER A MODERATELY UNSTABLE ATMOSPHERE AND BETTER SHEAR ENVIRONMENT. MAIN THREAT WILL BE GUSTY WINDS WITH LINE OF STORMS...AND SOME BOWING LINE SEGMENTS. STORMS WILL ALSO BE EFFICIENT PRECIP PRODUCERS WITH PWATS RUNNING 1.5 TO 2.0 INCHES LATER THIS AFTERNOON. KEPT MENTION OF LOCALLY HEAVY DOWNPOURS. WITH THE RECENT DRY CONDITIONS DO NOT SEE WIDESPREAD WATER PROBLEMS. HOWEVER...HEAVY DOWNPOURS COULD CAUSE LOCAL WATER PROBLEMS IF ANY REPETITIVE SHOWERS OCCUR. USED A BLEND OF BIAS CORRECTED DATA WITH PREVIOUS OFFICIAL FORECAST FOR TEMPS WHICH YIELDED A MINOR TWEAK TO THE TEMP FIELDS. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... NAM/GFS/ECMWF/CMC MODELS IN AGREEMENT IN THEIR QPF FIELDS PUSHING LAST RAIN SHOWERS OR THUNDERSTORMS TO THE EASTERN MOUNTAINS... MAINLY ACROSS THE SOUTH EARLY WEDNESDAY MORNING. THIS PCPN ACTIVITY IS ASSOCIATED WITH A SECOND COLD FRONT ENHANCED BY A H5 VORTICITY MAXIMA SINKING SOUTHEAST ACROSS THE AREA. BUFKIT SOUNDINGS INDICATE VERY DRY AIR ALOFT BEHIND THIS FRONT. YET ANOTHER H5 VORTICITY MAXIMA MOVES FROM THE NORTHWEST REACHING OUR EXTREME SOUTHEAST COUNTIES WEDNESDAY AFTERNOON. THEREFORE...DECIDED TO KEEP CHANCE POPS UNTIL THEN BEFORE ENDING ALL BY 00Z THURSDAY. TEMPERATURES WILL DEPEND ON THE DURATION OF CLOUD COVER ESPECIALLY WEDNESDAY AND THURSDAY. GENERALLY STAYED IN THE MID 80S LOWLANDS FOR WEDNESDAY...AND FEW DEGREES COOLER THURSDAY AS FLOW TURNS NORTHWEST TO NORTH BY THE AFTERNOON AND EVENING HOURS. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... USED A BLEND OF THE GFS AND ECMWF FOR FRIDAY. THIS LEAVES THE AREA UNDER A HIGH PRESSURE SYSTEM...BUT A BIT OF MOISTURE REMAINS IN THE NORTHERN MOUNTAINS....SO CAN NOT RULE OUT A THUNDERSTORM. FOR SATURDAY THROUGH MONDAY...SWITCHED TO A BLEND OF THE GFS/GEFS ENSEMBLE MEAN AND ECMWF ENSEMBLE MEAN. THIS BRINGS A SYSTEM INTO THE CENTRAL APPALACHIANS OVER THE WEEKEND...LINGERING INTO MONDAY. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... CONVECTION DYING OFF ACROSS CENTRAL AND NORTHERN WV...AND LATEST RADAR TRENDS KEEPS MOST OF THE ACTIVITY AWAY FROM TAF SITES. VFR EXPECTED FOR THE REMAINING OVERNIGHT HOURS. CONVECTIVE ACTIVITY INCREASES AGAIN FROM THE WEST AFTER 16Z. EXPECT GUSTY WINDS TO ACCOMPANY CONVECTION...ESPECIALLY AFTER 20Z AS NORTH-SOUTH BAND TRAVERSES ACROSS THE FORECAST AREA. EXPECT AT LEAST MVFR CONDITIONS WITH GUSTY WINDS AS BAND PASSES. LOCAL IFR CONDITIONS CAN BE EXPECTED INVOF HEAVIER PRECIPITATION CORES. STORM COVERAGE SHOULD GRADUALLY DECREASE IN COVERAGE ACROSS THE FAR NORTH...SOUTHEAST OHIO...TOWARDS END OF TAF PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: MORE WIDESPREAD IFR CONDITIONS DUE TO CONVECTION TUESDAY. 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 TUE 07/08/14 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 M M M BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H M H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 06Z WEDNESDAY... LOCAL IFR IN SHOWERS AND THUNDERSTORMS THROUGH EARLY WEDNESDAY... WITH LINGERING IFR CIGS POSSIBLE THROUGH LATE WEDNESDAY MORNING PARTICULARLY ACROSS HIGHER TERRAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KMC/ARJ NEAR TERM...KMC SHORT TERM...ARJ LONG TERM...RPY AVIATION...KMC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
352 AM EDT TUE JUL 8 2014 .SYNOPSIS... UNSETTLED WEATHER CONTINUES THROUGH EARLY WEDNESDAY AS A SERIES OF SYSTEMS PUSH EAST. HIGH PRESSURE BRINGS DRIER AIR TO THE REGION FOR THE END OF THE WEEK. ANOTHER SYSTEM OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... CUT BACK POP CHCS FOR THE EARLY MORNING HOURS AS OVERNIGHT CONVECTION DIED OFF RAPIDLY WITH THE LOSS OF DAYTIME HEATING. NEAR TERM HI-RES MODELS RUC13 AND HRRR ARE IN FAIR AGREEMENT IN TRANSITIONING ANOTHER CONVECTIVE BAND ACROSS THE FORECAST AREA THIS AFTERNOON. MAIN FLY IN THE OINTMENT IS TRANSITION OF DYING MCS OVER WESTERN ILLINOIS THAT SLIDING TO THE EAST-NORTHEAST AND SHOULD ARRIVE IN CENTRAL OH BY AROUND 15Z. EXPECT MAINLY RESIDUAL SHOWERS AT THIS TIME AND BOUNCED POPS BACK INTO CHC CATEGORY FOR SE OH TO ACCOUNT FOR THIS FEATURE. AFOREMENTIONED CONVECTIVE BAND MAY HAVE SOME TROUBLE DEVELOPING IN POST MCS ENVIRONMENT THIS AFTERNOON...BUT ONCE IT GETS GOING...IT SHOULD MAKE A LITTLE MORE HEADWAY INTO THE CWA AS COMPARED TO PREVIOUS BAND FROM YESTERDAY. LONGWAVE TROUGH OVER THE EASTERN US UNDERGOING AMPLIFICATION... WITH 5H FALLS OVER RLX AREA..AND MID LEVEL FLOW BECOMING MORE CYCLONIC. EXPECT A BETTER CHANCE FOR SVR STORMS TODAY UNDER A MODERATELY UNSTABLE ATMOSPHERE AND BETTER SHEAR ENVIRONMENT. MAIN THREAT WILL BE GUSTY WINDS WITH LINE OF STORMS...AND SOME BOWING LINE SEGMENTS. STORMS WILL ALSO BE EFFICIENT PRECIP PRODUCERS WITH PWATS RUNNING 1.5 TO 2.0 INCHES LATER THIS AFTERNOON. KEPT MENTION OF LOCALLY HEAVY DOWNPOURS. WITH THE RECENT DRY CONDITIONS DO NOT SEE WIDESPREAD WATER PROBLEMS. HOWEVER...HEAVY DOWNPOURS COULD CAUSE LOCAL WATER PROBLEMS IF ANY REPETITIVE SHOWERS OCCUR. USED A BLEND OF BIAS CORRECTED DATA WITH PREVIOUS OFFICIAL FORECAST FOR TEMPS WHICH YIELDED A MINOR TWEAK TO THE TEMP FIELDS. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... MODELS SHOW A COLD FRONT MOVING THROUGH THE REGION TUESDAY NIGHT. WILL INCREASE POPS SOME...ESPECIALLY DURING THE EVENING HOURS. GFS AND ECMWF ARE MUCH FASTER WITH THE COLD FRONT PUSHING THROUGH TUESDAY NIGHT/WEDNESDAY THAN THE NAM. SREF WOULD INDICATE THAT THE NAM IS A SLOW OUTLIER. THEREFORE...WILL LOWER POPS CONSIDERABLY ON WEDNESDAY AS HIGH PRESSURE BRINGS SOME DRIER AIR. GFS INDICATES THAT AN IMPULSE COULD COMBINE WITH SOME WEAK MOISTURE TO FIRE A COUPLE OF STORMS IN THE MOUNTAINS ON THURSDAY. THEREFORE...WILL LEAVE SMALL POPS IN THAT AREA DURING THE AFTERNOON HOURS. && .LONG TERM /FRIDAY THROUGH MONDAY/... USED A BLEND OF THE GFS AND ECMWF FOR FRIDAY. THIS LEAVES THE AREA UNDER A HIGH PRESSURE SYSTEM...BUT A BIT OF MOISTURE REMAINS IN THE NORTHERN MOUNTAINS....SO CAN NOT RULE OUT A THUNDERSTORM. FOR SATURDAY THROUGH MONDAY...SWITCHED TO A BLEND OF THE GFS/GEFS ENSEMBLE MEAN AND ECMWF ENSEMBLE MEAN. THIS BRINGS A SYSTEM INTO THE CENTRAL APPALACHIANS OVER THE WEEKEND...LINGERING INTO MONDAY. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... CONVECTION DYING OFF ACROSS CENTRAL AND NORTHERN WV...AND LATEST RADAR TRENDS KEEPS MOST OF THE ACTIVITY AWAY FROM TAF SITES. VFR EXPECTED FOR THE REMAINING OVERNIGHT HOURS. CONVECTIVE ACTIVITY INCREASES AGAIN FROM THE WEST AFTER 16Z. EXPECT GUSTY WINDS TO ACCOMPANY CONVECTION...ESPECIALLY AFTER 20Z AS NORTH-SOUTH BAND TRAVERSES ACROSS THE FORECAST AREA. EXPECT AT LEAST MVFR CONDITIONS WITH GUSTY WINDS AS BAND PASSES. LOCAL IFR CONDITIONS CAN BE EXPECTED INVOF HEAVIER PRECIPITATION CORES. STORM COVERAGE SHOULD GRADUALLY DECREASE IN COVERAGE ACROSS THE FAR NORTH...SOUTHEAST OHIO...TOWARDS END OF TAF PERIOD. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: MORE WIDESPREAD IFR CONDITIONS DUE TO CONVECTION TUESDAY. 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 TUE 07/08/14 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 M M M BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H M H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 06Z WEDNESDAY... LOCAL IFR IN SHOWERS AND THUNDERSTORMS THROUGH EARLY WEDNESDAY... WITH LINGERING IFR CIGS POSSIBLE THROUGH LATE WEDNESDAY MORNING PARTICULARLY ACROSS HIGHER TERRAIN. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KMC NEAR TERM...KMC SHORT TERM...RPY LONG TERM...RPY AVIATION...KMC
AREA FORECAST DISCUSSION
NWS TULSA OK
952 PM CDT WED JUL 9 2014 .DISCUSSION... DIFFUSE FRONTAL ZONE EXTENDING FROM ARKLATEX NORTHWEST INTO SW KANSAS THIS EVENING IS EXPECTED TO GRADUALLY LIFT NORTH OVERNIGHT. 00Z NAM SHOWS BOUNDARY AT 8590MB FROM ABOUT FSM-ICT BY 12Z THURSDAY. CLUSTERS OF STORMS CONTINUE TO ORGANIZE ACROSS NEBRASKA AND NORTHERN KANSAS THIS EVENING AND SHOULD CONTINUE GROWING UPSCALE AS LOW LEVEL WARM ADVECTION STRENGTHENS. GOOD CHANCE THAT AN ORGANIZED COMPLEX OF STORMS WILL DEVELOP THERE AND MOVE SE OVERNIGHT LIKELY REACHING PARTS OF NE OKLAHOMA BEFORE 12Z. EXISTING FORECAST POP CONFIGURATION BASICALLY GOOD...BUT HAVE RAISED TO LIKELY IN AREAS NW OF TULSA AFTER 09Z AS HRRR HAS REMAINED VERY CONSISTENT IN BRINGING COMPLEX TO THESE AREAS 09-12Z. ALSO BUMPED POPS UP SOME FOR 12-18Z THURSDAY NORTH OF I-40. SEVERE THREAT WILL BE DEPENDENT ON HOW ORGANIZED COLD POOL CAN BECOME...AT THIS TIME IT STILL LOOKS LIMITED. UPDATED PRODUCTS WILL BE OUT SHORTLY. && .PREV DISCUSSION... /ISSUED 628 PM CDT WED JUL 9 2014/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS EXPECTED THIS EVENING AND THROUGH MOST OF THE NIGHT. THUNDERSTORMS SHOULD DEVELOP ACROSS KS TONIGHT EVENTUALLY IMPACTING ALL TAF SITES AROUND 10-12Z. BRIEF MVFR CIGS/VSBYS POSSIBLE IN AND NEAR STORMS. PREV DISCUSSION... /ISSUED 341 PM CDT WED JUL 9 2014/ DISCUSSION... WEAKENING FRONTAL ZONE REMAINS ALONG THE RED RIVER AND WILL BEGIN ITS NORTHEASTWARD MOVEMENT TONIGHT THROUGH THURSDAY. THE MOST LIKELY SCENARIO FOR OVERNIGHT STORMS IS AN EXPANDING COMPLEX TO DEVELOP ACROSS THE HIGH PLAINS...AND TRACK SOUTHEASTWARD INTO THE AREA. HIGHEST PRECIP CHANCES WILL BE FOCUSED ACROSS NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA ACCORDINGLY. THE RETURN TO HOT AND HUMID CONDITIONS WILL BEGIN ON FRIDAY WITH TEMPERATURES PEAKING SATURDAY INTO SUNDAY. A FEW STORMS MAY DEVELOP IN THE HIGHER TERRAIN EACH DAY HOWEVER CHANCES WILL REMAIN VERY LOW. AN INITIAL WIND SHIFT BEING AN INITIAL FRONTAL BOUNDARY AND/OR CONVECTIVE OUTFLOW WILL MAKE A PUSH INTO NORTHEAST OKLAHOMA ON SUNDAY. THIS RAISES UNCERTAINTIES ON TEMPS IN THIS ZONE...WHILE HOT TEMPS PREVAIL FURTHER SOUTH ACROSS MUCH OF THE FORECAST AREA. THIS BOUNDARY WILL SLOWLY WORK SOUTHWARD SUNDAY NIGHT THROUGH MONDAY...BEFORE A STRONGER SURGE OF COOLER AND DRIER AIR ARRIVES FOR TUESDAY THROUGH MID NEXT WEEK. THE BOUNDARY WILL ALSO MARK A ZONE OF INCREASED PRECIPITATION CHANCES. THE TEMPERATURES FOR MID TO LATE NEXT WEEK CONTINUE TO BE SHOWN ABNORMALLY COOL FOR THIS TIME OF THE YEAR...AND SHOULD THIS VERIFY IT WILL BE A MARKED CHANGE FROM THE UPCOMING WEEKEND TEMPS. && .PRELIMINARY POINT TEMPS/POPS... TUL 69 91 75 97 / 40 50 0 0 FSM 70 91 73 94 / 10 40 0 0 MLC 73 92 74 94 / 20 10 0 0 BVO 65 87 72 97 / 50 50 0 0 FYV 63 87 70 89 / 10 40 10 10 BYV 63 86 69 89 / 10 30 10 10 MKO 69 91 73 94 / 20 40 0 0 MIO 65 88 71 92 / 20 50 10 0 F10 71 91 73 94 / 20 30 0 0 HHW 72 94 73 95 / 10 10 0 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...14 LONG TERM....99
AREA FORECAST DISCUSSION
NWS NORMAN OK
613 PM CDT WED JUL 9 2014 .DISCUSSION... THE 00Z AVIATION DISCUSSION FOLLOWS.... && .AVIATION... ONCE AGAIN THERE IS GREAT UNCERTAINTY REGARDING THE PLACEMENT AND TIMING OF SHRA/TSRA ACROSS THE REGION TONIGHT. THE MOST LIKELY SCENARIO IS THAT A STORM CLUSTER OVER KS WILL ADVANCE SE OVERNIGHT...AFFECTING KPNC/KOKC/KOUN LATE TONIGHT...AND PROBABLY ENDING AROUND SUNRISE. ANOTHER PLAUSIBLE SITUATION IS THAT A STORM CLUSTER WILL ALSO FORM OVER THE TX PANHANDLE...AND BRING SOME TSRA INTO FAR W OK...POSSIBLY AFFECTING KHBR/KCSM/KGAG/KWWR LATE THIS EVENING OR TONIGHT. NO EXTENDED PERIODS OF NON-VFR CONDITIONS ARE EXPECTED. WINDS WILL TURN SLOWLY AROUND FROM SE TO S TOMORROW MORNING. && .PREV DISCUSSION... /ISSUED 305 PM CDT WED JUL 9 2014/ DISCUSSION... OVERNIGHT/MORNING CONVECTION HAS MAINLY DISSIPATED THIS AFTERNOON WITH THE EXCEPTION OF A FEW SHOWERS IN SOUTH CENTRAL OKLAHOMA. NEW CONVECTION IS DEVELOPING IN NORTH TEXAS ALONG A STALLED FRONTAL BOUNDARY. CU FIELD EXTENDS FROM THIS DEVELOPING CONVECTION INTO THE TEXAS PANHANDLE NEAR AMARILLO. RECENT HRRR RUNS...DEVELOP STORMS IN THE CENTRAL TEXAS PANHANDLE AND MOVE STORMS GENERALLY EAST DURING THE LATE AFTERNOON/EARLY EVENING. BASED ON CURRENT TRENDS...THIS SEEM PLAUSIBLE. OTHER STORMS ARE EXPECTED TO FORM IN WESTERN NEBRASKA/KANSAS IN ADVANCE OF A SHORTWAVE. THIS ACTIVITY IS EXPECTED ENTER NORTHERN OKLAHOMA DURING THE LATE EVENING/OVERNIGHT. WILL KEEP HIGHEST POPS ACROSS NORTH CENTRAL OKLAHOMA. OVERNIGHT CONVECTION MAY LINGER INTO THURSDAY MORNING...THEN A BUILDING RIDGE ACROSS THE SOUTHERN PLAINS SHOULD GREATLY REDUCE RAIN/STORM CHANCES. HOT WEATHER WILL BE THE RULE OVER THE WEEKEND. NOT SURE IF HEAT ADVISORIES WILL BE NECESSARY AT THIS TIME. BY TUESDAY OF NEXT WEEK...MOST MODELS PUSH A SIGNIFICANT FRONT INTO OKLAHOMA AND NORTH TEXAS (AT LEAST BY JULY STANDARDS). THE FRONT ALONG WITH A DECENT WAVE...MAY RESULT IN WIDESPREAD PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 72 96 73 98 / 30 10 0 0 HOBART OK 73 98 73 100 / 20 0 0 0 WICHITA FALLS TX 76 98 75 100 / 20 0 0 0 GAGE OK 71 97 71 99 / 30 0 0 0 PONCA CITY OK 69 96 74 98 / 50 30 10 0 DURANT OK 74 94 74 96 / 20 10 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 84/23/23
AREA FORECAST DISCUSSION
NWS TULSA OK
1256 PM CDT TUE JUL 8 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. FRONTAL BOUNDARY SOUTHWEST OK THROUGH EASTERN OK INTO SOUTHWEST MO DRIFTING SOUTHEAST WILL BE FOCUS FOR POTENTIAL THUNDERSTORM DEVELOPMENT. MOST LIKELY TIME FRAME 00Z-06Z. AT THIS TIME...TAF SITES KMLC KFSM MOST LIKELY TO SEE AT LEAST VICINITY THUNDER...SITES KBVO KTUL KRVS LEAST LIKELY. OTHER THAN THUNDERSTORM DEVELOPMENT...VFR. && .PREV DISCUSSION... /ISSUED 1051 AM CDT TUE JUL 8 2014/ DISCUSSION... FRONTAL BOUNDARY IN THE VICINITY OF I-44 FORECAST TO CONTINUE TO DRIFT SOUTH THIS AFTERNOON/TONIGHT THEN STALL LATE TONIGHT BETWEEN I40 AND RED RIVER. LEFT OVER -SHRA FAR NORTHEAST OK FAR NORTHWEST AR DIMINISHING. IN THE SHORT TERM REMOVED NOON - 4PM POPS WHILE LEAVING LATE AFTERNOON POPS NORTH I-40 FOR POTENTIAL REGENERATION THUNDER NEAR BOUNDARY. GW PREV DISCUSSION... /ISSUED 638 AM CDT TUE JUL 8 2014/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. GENERALLY VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AT MOST SITES THIS AFTERNOON AND TONIGHT WHICH MAY BRIEFLY REDUCE CEILINGS AND VISIBILITIES. PREV DISCUSSION... /ISSUED 409 AM CDT TUE JUL 8 2014/ DISCUSSION... THE SOUTHWEST PORTION OF A MCS MOVING THROUGH MISSOURI HAD CLIPPED NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS EARLY THIS MORNING. THIS ACTIVITY SHOULD CONTINUE TO PUSH SOUTHEAST AND DISSIPATE OVER THE CWA DURING THE NEXT COUPLE OF HOURS. AN ADDITIONAL LINE OF CONVECTION WAS ACROSS CENTRAL KANSAS...MOVING TO THE SOUTHEAST. WILL LEAVE SLIGHT CHANCE POPS FOR THE MORNING HOURS ACROSS FAR NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS. LATEST HRRR AND LOCAL IN-HOUSE MODEL INDICATE THIS LINE TRYING TO FALL APART JUST BEFORE IT GETS INTO THE CWA THIS MORNING. A COLD FRONT CURRENTLY OVER CENTRAL KANSAS WILL MOVE INTO THE CWA TODAY...SHIFTING WINDS OUT OF THE NORTH NORTHEAST. THIS WILL HELP TEMPS ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS BE A LITTLE COOLER COMPARED TO YESTERDAY. CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY FOR THE NORTHERN PART OF THE CWA AS THE FRONT SAGS SOUTHWARD TO NEAR INTERSTATE 40 BY THIS EVENING. AFTERNOON HEATING COULD ALLOW FOR ENOUGH INSTABILITY TO DEVELOP ALONG THE FRONT THAT SOME THUNDERSTORMS COULD BECOME STRONG TO SEVERE WITH LARGE HAIL AND STRONG WINDS BEING THE MAIN HAZARDS. GREATER CHANCES FOR SHOWERS AND THUNDERSTORMS ARE FORECAST ACROSS MUCH OF THE CWA TONIGHT INTO WEDNESDAY AS THE FRONT STALLS OUT NEAR THE RED RIVER BY WEDNESDAY MORNING. PERIODS OF HEAVY RAINFALL MAY BE POSSIBLE ALONG WITH A LIMITED SEVERE POTENTIAL. SLIGHTLY COOLER TEMPS WILL AGAIN BE POSSIBLE WEDNESDAY WITH HIGHS IN THE UPPER 80S/LOWER 90S. THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY AND THEN BEGINS TO LIFT NORTHWARD THURSDAY AS A WARM FRONT. THUS...WILL KEEP AT LEAST SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS GOING THROUGH THURSDAY. A RIDGE OF HIGH PRESSURE BUILDS BACK OVER THE SOUTHERN PLAINS IN THE WAKE OF THE EXITING FRONTAL BOUNDARY AND SHORTWAVE TROF AXIS MOVING ACROSS THE MIDWEST. THIS WILL ALLOW FOR SOUTHERLY WINDS ALONG WITH HOT AND HUMID CONDITIONS TO RETURN TO EASTERN OKLAHOMA AND NORTHWEST ARKANSAS FOR THE WEEKEND. HIGH TEMPS NEAR 100 DEGREES WILL AGAIN BE POSSIBLE FOR PARTS OF EASTERN OKLAHOMA. THESE HOT TEMPS COULD BE SHORT LIVED AS EXTENDED MODEL SOLUTIONS CONTINUE TO SHOW A LOW PRESSURE SYSTEM DROPPING OUT OF CANADA INTO THE GREAT LAKES REGION WITH A COLD FRONT PUSHING ACROSS THE PLAINS FOR THE FIRST PART OF NEXT WEEK. THERE REMAINS TIMING AND STRENGTH DIFFERENCES WITH THIS SYSTEM...THOUGH SOME COOLER TEMPS AND PRECIP CHANCES LOOK POSSIBLE ACROSS THE CWA. && .PRELIMINARY POINT TEMPS/POPS... TUL 93 69 90 71 / 20 30 10 30 FSM 96 72 89 72 / 20 40 30 30 MLC 96 73 91 73 / 10 40 20 30 BVO 90 66 89 69 / 20 20 10 30 FYV 90 66 86 66 / 30 40 10 20 BYV 90 66 86 66 / 30 30 10 20 MKO 95 70 89 71 / 20 30 20 30 MIO 90 65 88 66 / 20 20 10 20 F10 96 71 90 72 / 10 30 20 30 HHW 96 74 93 73 / 10 20 30 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...21 LONG TERM....07 AVIATION...21
AREA FORECAST DISCUSSION
NWS TULSA OK
1051 AM CDT TUE JUL 8 2014 .DISCUSSION... FRONTAL BOUNDARY IN THE VICINITY OF I-44 FORECAST TO CONTINUE TO DRIFT SOUTH THIS AFTERNOON/TONIGHT THEN STALL LATE TONIGHT BETWEEN I40 AND RED RIVER. LEFT OVER -SHRA FAR NORTHEAST OK FAR NORTHWEST AR DIMINISHING. IN THE SHORT TERM REMOVED NOON - 4PM POPS WHILE LEAVING LATE AFTERNOON POPS NORTH I-40 FOR POTENTIAL REGENERATION THUNDER NEAR BOUNDARY. GW && .PREV DISCUSSION... /ISSUED 638 AM CDT TUE JUL 8 2014/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. GENERALLY VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AT MOST SITES THIS AFTERNOON AND TONIGHT WHICH MAY BRIEFLY REDUCE CEILINGS AND VISIBILITIES. PREV DISCUSSION... /ISSUED 409 AM CDT TUE JUL 8 2014/ DISCUSSION... THE SOUTHWEST PORTION OF A MCS MOVING THROUGH MISSOURI HAD CLIPPED NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS EARLY THIS MORNING. THIS ACTIVITY SHOULD CONTINUE TO PUSH SOUTHEAST AND DISSIPATE OVER THE CWA DURING THE NEXT COUPLE OF HOURS. AN ADDITIONAL LINE OF CONVECTION WAS ACROSS CENTRAL KANSAS...MOVING TO THE SOUTHEAST. WILL LEAVE SLIGHT CHANCE POPS FOR THE MORNING HOURS ACROSS FAR NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS. LATEST HRRR AND LOCAL IN-HOUSE MODEL INDICATE THIS LINE TRYING TO FALL APART JUST BEFORE IT GETS INTO THE CWA THIS MORNING. A COLD FRONT CURRENTLY OVER CENTRAL KANSAS WILL MOVE INTO THE CWA TODAY...SHIFTING WINDS OUT OF THE NORTH NORTHEAST. THIS WILL HELP TEMPS ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS BE A LITTLE COOLER COMPARED TO YESTERDAY. CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY FOR THE NORTHERN PART OF THE CWA AS THE FRONT SAGS SOUTHWARD TO NEAR INTERSTATE 40 BY THIS EVENING. AFTERNOON HEATING COULD ALLOW FOR ENOUGH INSTABILITY TO DEVELOP ALONG THE FRONT THAT SOME THUNDERSTORMS COULD BECOME STRONG TO SEVERE WITH LARGE HAIL AND STRONG WINDS BEING THE MAIN HAZARDS. GREATER CHANCES FOR SHOWERS AND THUNDERSTORMS ARE FORECAST ACROSS MUCH OF THE CWA TONIGHT INTO WEDNESDAY AS THE FRONT STALLS OUT NEAR THE RED RIVER BY WEDNESDAY MORNING. PERIODS OF HEAVY RAINFALL MAY BE POSSIBLE ALONG WITH A LIMITED SEVERE POTENTIAL. SLIGHTLY COOLER TEMPS WILL AGAIN BE POSSIBLE WEDNESDAY WITH HIGHS IN THE UPPER 80S/LOWER 90S. THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY AND THEN BEGINS TO LIFT NORTHWARD THURSDAY AS A WARM FRONT. THUS...WILL KEEP AT LEAST SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS GOING THROUGH THURSDAY. A RIDGE OF HIGH PRESSURE BUILDS BACK OVER THE SOUTHERN PLAINS IN THE WAKE OF THE EXITING FRONTAL BOUNDARY AND SHORTWAVE TROF AXIS MOVING ACROSS THE MIDWEST. THIS WILL ALLOW FOR SOUTHERLY WINDS ALONG WITH HOT AND HUMID CONDITIONS TO RETURN TO EASTERN OKLAHOMA AND NORTHWEST ARKANSAS FOR THE WEEKEND. HIGH TEMPS NEAR 100 DEGREES WILL AGAIN BE POSSIBLE FOR PARTS OF EASTERN OKLAHOMA. THESE HOT TEMPS COULD BE SHORT LIVED AS EXTENDED MODEL SOLUTIONS CONTINUE TO SHOW A LOW PRESSURE SYSTEM DROPPING OUT OF CANADA INTO THE GREAT LAKES REGION WITH A COLD FRONT PUSHING ACROSS THE PLAINS FOR THE FIRST PART OF NEXT WEEK. THERE REMAINS TIMING AND STRENGTH DIFFERENCES WITH THIS SYSTEM...THOUGH SOME COOLER TEMPS AND PRECIP CHANCES LOOK POSSIBLE ACROSS THE CWA. && .PRELIMINARY POINT TEMPS/POPS... TUL 93 69 90 71 / 20 30 10 30 FSM 96 72 89 72 / 20 40 30 30 MLC 96 73 91 73 / 10 40 20 30 BVO 90 66 89 69 / 20 20 10 30 FYV 90 66 86 66 / 30 40 10 20 BYV 90 66 86 66 / 30 30 10 20 MKO 95 70 89 71 / 20 30 20 30 MIO 90 65 88 66 / 20 20 10 20 F10 96 71 90 72 / 10 30 20 30 HHW 96 74 93 73 / 10 20 30 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...21 LONG TERM....07
AREA FORECAST DISCUSSION
NWS TULSA OK
638 AM CDT TUE JUL 8 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. GENERALLY VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AT MOST SITES THIS AFTERNOON AND TONIGHT WHICH MAY BRIEFLY REDUCE CEILINGS AND VISIBILITIES. && .PREV DISCUSSION... /ISSUED 409 AM CDT TUE JUL 8 2014/ DISCUSSION... THE SOUTHWEST PORTION OF A MCS MOVING THROUGH MISSOURI HAD CLIPPED NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS EARLY THIS MORNING. THIS ACTIVITY SHOULD CONTINUE TO PUSH SOUTHEAST AND DISSIPATE OVER THE CWA DURING THE NEXT COUPLE OF HOURS. AN ADDITIONAL LINE OF CONVECTION WAS ACROSS CENTRAL KANSAS...MOVING TO THE SOUTHEAST. WILL LEAVE SLIGHT CHANCE POPS FOR THE MORNING HOURS ACROSS FAR NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS. LATEST HRRR AND LOCAL IN-HOUSE MODEL INDICATE THIS LINE TRYING TO FALL APART JUST BEFORE IT GETS INTO THE CWA THIS MORNING. A COLD FRONT CURRENTLY OVER CENTRAL KANSAS WILL MOVE INTO THE CWA TODAY...SHIFTING WINDS OUT OF THE NORTH NORTHEAST. THIS WILL HELP TEMPS ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS BE A LITTLE COOLER COMPARED TO YESTERDAY. CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY FOR THE NORTHERN PART OF THE CWA AS THE FRONT SAGS SOUTHWARD TO NEAR INTERSTATE 40 BY THIS EVENING. AFTERNOON HEATING COULD ALLOW FOR ENOUGH INSTABILITY TO DEVELOP ALONG THE FRONT THAT SOME THUNDERSTORMS COULD BECOME STRONG TO SEVERE WITH LARGE HAIL AND STRONG WINDS BEING THE MAIN HAZARDS. GREATER CHANCES FOR SHOWERS AND THUNDERSTORMS ARE FORECAST ACROSS MUCH OF THE CWA TONIGHT INTO WEDNESDAY AS THE FRONT STALLS OUT NEAR THE RED RIVER BY WEDNESDAY MORNING. PERIODS OF HEAVY RAINFALL MAY BE POSSIBLE ALONG WITH A LIMITED SEVERE POTENTIAL. SLIGHTLY COOLER TEMPS WILL AGAIN BE POSSIBLE WEDNESDAY WITH HIGHS IN THE UPPER 80S/LOWER 90S. THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY AND THEN BEGINS TO LIFT NORTHWARD THURSDAY AS A WARM FRONT. THUS...WILL KEEP AT LEAST SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS GOING THROUGH THURSDAY. A RIDGE OF HIGH PRESSURE BUILDS BACK OVER THE SOUTHERN PLAINS IN THE WAKE OF THE EXITING FRONTAL BOUNDARY AND SHORTWAVE TROF AXIS MOVING ACROSS THE MIDWEST. THIS WILL ALLOW FOR SOUTHERLY WINDS ALONG WITH HOT AND HUMID CONDITIONS TO RETURN TO EASTERN OKLAHOMA AND NORTHWEST ARKANSAS FOR THE WEEKEND. HIGH TEMPS NEAR 100 DEGREES WILL AGAIN BE POSSIBLE FOR PARTS OF EASTERN OKLAHOMA. THESE HOT TEMPS COULD BE SHORT LIVED AS EXTENDED MODEL SOLUTIONS CONTINUE TO SHOW A LOW PRESSURE SYSTEM DROPPING OUT OF CANADA INTO THE GREAT LAKES REGION WITH A COLD FRONT PUSHING ACROSS THE PLAINS FOR THE FIRST PART OF NEXT WEEK. THERE REMAINS TIMING AND STRENGTH DIFFERENCES WITH THIS SYSTEM...THOUGH SOME COOLER TEMPS AND PRECIP CHANCES LOOK POSSIBLE ACROSS THE CWA. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...05
AREA FORECAST DISCUSSION
NWS TULSA OK
409 AM CDT TUE JUL 8 2014 .DISCUSSION... THE SOUTHWEST PORTION OF A MCS MOVING THROUGH MISSOURI HAD CLIPPED NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS EARLY THIS MORNING. THIS ACTIVITY SHOULD CONTINUE TO PUSH SOUTHEAST AND DISSIPATE OVER THE CWA DURING THE NEXT COUPLE OF HOURS. AN ADDITIONAL LINE OF CONVECTION WAS ACROSS CENTRAL KANSAS...MOVING TO THE SOUTHEAST. WILL LEAVE SLIGHT CHANCE POPS FOR THE MORNING HOURS ACROSS FAR NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS. LATEST HRRR AND LOCAL IN-HOUSE MODEL INDICATE THIS LINE TRYING TO FALL APART JUST BEFORE IT GETS INTO THE CWA THIS MORNING. A COLD FRONT CURRENTLY OVER CENTRAL KANSAS WILL MOVE INTO THE CWA TODAY...SHIFTING WINDS OUT OF THE NORTH NORTHEAST. THIS WILL HELP TEMPS ACROSS NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS BE A LITTLE COOLER COMPARED TO YESTERDAY. CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY FOR THE NORTHERN PART OF THE CWA AS THE FRONT SAGS SOUTHWARD TO NEAR INTERSTATE 40 BY THIS EVENING. AFTERNOON HEATING COULD ALLOW FOR ENOUGH INSTABILITY TO DEVELOP ALONG THE FRONT THAT SOME THUNDERSTORMS COULD BECOME STRONG TO SEVERE WITH LARGE HAIL AND STRONG WINDS BEING THE MAIN HAZARDS. GREATER CHANCES FOR SHOWERS AND THUNDERSTORMS ARE FORECAST ACROSS MUCH OF THE CWA TONIGHT INTO WEDNESDAY AS THE FRONT STALLS OUT NEAR THE RED RIVER BY WEDNESDAY MORNING. PERIODS OF HEAVY RAINFALL MAY BE POSSIBLE ALONG WITH A LIMITED SEVERE POTENTIAL. SLIGHTLY COOLER TEMPS WILL AGAIN BE POSSIBLE WEDNESDAY WITH HIGHS IN THE UPPER 80S/LOWER 90S. THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY AND THEN BEGINS TO LIFT NORTHWARD THURSDAY AS A WARM FRONT. THUS...WILL KEEP AT LEAST SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS GOING THROUGH THURSDAY. A RIDGE OF HIGH PRESSURE BUILDS BACK OVER THE SOUTHERN PLAINS IN THE WAKE OF THE EXITING FRONTAL BOUNDARY AND SHORTWAVE TROF AXIS MOVING ACROSS THE MIDWEST. THIS WILL ALLOW FOR SOUTHERLY WINDS ALONG WITH HOT AND HUMID CONDITIONS TO RETURN TO EASTERN OKLAHOMA AND NORTHWEST ARKANSAS FOR THE WEEKEND. HIGH TEMPS NEAR 100 DEGREES WILL AGAIN BE POSSIBLE FOR PARTS OF EASTERN OKLAHOMA. THESE HOT TEMPS COULD BE SHORT LIVED AS EXTENDED MODEL SOLUTIONS CONTINUE TO SHOW A LOW PRESSURE SYSTEM DROPPING OUT OF CANADA INTO THE GREAT LAKES REGION WITH A COLD FRONT PUSHING ACROSS THE PLAINS FOR THE FIRST PART OF NEXT WEEK. THERE REMAINS TIMING AND STRENGTH DIFFERENCES WITH THIS SYSTEM...THOUGH SOME COOLER TEMPS AND PRECIP CHANCES LOOK POSSIBLE ACROSS THE CWA. && .PRELIMINARY POINT TEMPS/POPS... TUL 93 69 90 71 / 20 30 10 30 FSM 96 72 89 72 / 20 40 30 30 MLC 96 73 91 73 / 10 40 20 30 BVO 90 66 89 69 / 20 20 10 30 FYV 90 66 86 66 / 30 40 10 20 BYV 90 66 86 66 / 30 30 10 20 MKO 95 70 89 71 / 20 30 20 30 MIO 90 65 88 66 / 20 20 10 20 F10 96 71 90 72 / 10 30 20 30 HHW 96 74 93 73 / 10 20 30 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...05 LONG TERM....20
AREA FORECAST DISCUSSION
NWS PORTLAND OR
219 PM PDT TUE JUL 8 2014 .SYNOPSIS...AN UPPER LEVEL TROUGH MOVING ACROSS BRITISH COLUMBIA TONIGHT AND WEDNESDAY WILL SUPPRESS THE FOUR-CORNERS HIGH AND ALLOW A SLIGHT INCREASE IN ONSHORE LOW-LEVEL FLOW. IT WILL BE A FEW DEGREES COOLER INLAND WEDNESDAY WITH ANY INSTABILITY PUSHED WELL EAST. THE FOUR-CORNERS HIGH EXPANDS NORTH AGAIN LATE IN THE WEEK AND OVER THE WEEKEND. A MOIST SOUTH MID-LEVEL FLOW MAY RETURN FRIDAY AND PERSIST THROUGH THE WEEKEND FOR A THREAT OF THUNDERSTORMS. && .SHORT TERM...THROUGH FRIDAY... WATER VAPOR IMAGERY EARLY THIS AFTERNOON SHOWING A 594 DM HIGH PRES CENTER SQUARELY OVER THE FOUR-CORNERS REGION...WITH A SOUTHEAST TO NORTHWEST ORIENTED RIDGE AXIS EXTENDING THROUGH NORTHWEST OREGON. MID AND HIGH-LEVEL MOISTURE...GENERALLY ABOVE 15000 FT MSL...HAS REACHED THE COLUMBIA RIVER. THERE LOOKS TO BE A SHORT-WAVE DISTURBANCE JUST OFF THE S OREGON COAST...CLOSE TO THE 6-HR GFS FORECAST. AS OF 20Z NO LIGHTNING DETECTED OVER NRN CA...THE NRN SIERRAS...AND MORE IMPORTANTLY OVER THE NRN CA SISKIYOUS CLOSEST TO THE SHORT-WAVE DISTURBANCE. OVERALL PATTERN REMAINS BASICALLY UNCHANGED FROM YESTERDAYS MODEL RUNS. BIGGEST FORECAST CHALLENGE REMAINS POTENTIAL THUNDERSTORM DEVELOPMENT. ANY THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON AND THIS EVENING FAVORS THE LANE COUNTY CASCADES...BUT WILL HAVE TO WATCH FOR ANYTHING WESTWARD. 12Z MODEL SOUNDINGS FOR KEUG AND FOR A POINT IN THE N OREGON CASCADES DO NOT SEEM TOO SUPPORTIVE FOR ANY THUNDERSTORM DEVELOPMENT. BASICALLY TOO MUCH CIN TO OVERCOME AND A STRONG MID-LEVEL INVERSION TO BREAK. 18Z HRRR RUN BRINGS SOME 25-30 DBZ ECHOES INTO SERN LANE COUNTY AROUND 06Z WED...THEN QUICKLY DISSIPATING BY 08Z. 19Z RAP40 RUN NOT VERY IMPRESSIVE EITHER...KEEPING THE HIGHEST SURFACE-BASED CONVECTIVE AVAILABLE POTENTIAL ENERGY (CAPE) VALUES ALONG THE OREGON CASCADE CREST FROM ABOUT MT. JEFFERSON SOUTHWARD BEGINNING LATE THIS AFTERNOON...THEN SHIFTING TO THE EAST CASCADE SLOPES IN THE EARLY EVENING. THE RAP40 700 MB STREAMLINE FORECAST ALSO SHOWS MORE WEST COMPONENT BEGINNING 00Z WED...FURTHER DIMINISHING THUNDERSTORM POTENTIAL. OPTED TO DELAY ANY MENTION OF THUNDERSTORMS TO 00Z WED. NOT 100 PERCENT CONFIDENT ENOUGH TO REMOVE THEM COMPLETELY FROM THE FORECAST. UPPER LEVEL TROUGH MOVES ACROSS BRITISH COLUMBIA LATE TONIGHT AND WEDNESDAY. THIS WILL STRENGTHEN THE WLY FLOW ALOFT OVER THE AREA AND INCREASE THE ONSHORE LOW-LEVEL FLOW. EXPECT GREATER COVERAGE OF MARINE CLOUDS WED MORNING...BUT THE PRIMARY IMPACT WILL BE A FEW DEGREES OF COOLING AND...ACCORDING TO MODEL GUIDANCE...LOWER DEW POINTS. SLIGHTLY WARMER THURSDAY WITH A LITTLE INCREASE IN 500 MB HEIGHTS AND GFS 850 MB TEMPS GOING FROM 16C WED TO 18C THU. GFS AND ECMWF SHOW THE 4-CORNERS HIGH EXPANDING NORTHWEST AGAIN FRI WITH A SHORT-WAVE ALONG THE N CA AND SRN OREGON COAST EMBEDDED WITHIN SOUTH FLOW ALOFT. IN OTHER WORDS...A CLASSICAL THUNDERSTORM PATTERN AND SOMETHING THAT HAS BEEN MENTIONED...ESPECIALLY TO THE FIRE WEATHER CUSTOMERS...FOR THE PAST COUPLE OF DAYS. WEISHAAR .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A WEAK UPPER-LEVEL SHORTWAVE IS FORECAST TO ROTATE INTO THE REGION FROM THE SOUTH LATE FRIDAY. THIS MAY BRING ENOUGH FORCING TO TRIGGER A FEW SHOWERS OR THUNDERSHOWERS IN THE NORTH OREGON AND LANE COUNTY CASCADES THROUGH FRIDAY EVENING. ANOTHER MORE SUBSTANTIAL UPPER-LEVEL LOW WILL THEN APPROACH THE COAST LATE SATURDAY INTO SUNDAY. DEPENDING ON THE TIMING AND POSITIONING OF THE TROUGH...THIS MAY PROVIDE AN EVEN BETTER CHANCE FOR THUNDER ON SUNDAY. FORECAST SOUNDINGS INDICATED INCREASING MID-LEVEL MOISTURE AND SUFFICIENT INSTABILITY TO JUSTIFY ADDING A SLIGHT CHANCE OF THUNDER SUNDAY AFTERNOON. A RIDGE BUILDS IN BEHIND THE DEPARTING TROUGH EARLY NEXT WEEK...BRINGING A RETURN TO THE TYPICAL SUMMER-TIME NORTHWESTERLY FLOW REGIME. && .AVIATION...VFR CONDITIONS THIS AFTERNOON...EXCEPT FOR THE CENTRAL OREGON COAST NEAR KONP WHERE MARINE STRATUS IS RESULTING IN IFR CIGS. GUSTY NORTHERLY WINDS ALONG THE COAST THIS AFTERNOON WILL WEAKEN TONIGHT. MARINE STRATUS WILL FILL IN ALONG THE COAST LATE THIS AFTERNOON WITH IFR CIGS. THE STRATUS WILL PUSH IN THROUGH THE COASTAL GAPS THIS EVENING WITH MVFR CIGS REACHING KKLS AROUND 07Z AND KPDX AROUND 13Z. PATCHES OF STATUS WILL FORM AGAIN IN THE WILLAMETTE VALLEY EARLY WED...WITH A GREATER EMPHASIS FOR THE FOOTHILLS AND NORTHERN VALLEY...AND DO NOT EXPECT KSLE OR KEUG TO BE IMPACTED MUCH. KPDX AND APPROACHES...VFR CONDITIONS THIS AFTERNOON AND EVENING. HIGH LEVEL CLOUDS WILL INCREASE IN COVERAGE THIS EVENING. MVFR CIGS FROM STRATUS EXPECTED BETWEEN 12Z AND 17Z ON WED. TJ && .MARINE...HIGH PRESSURE OVER THE NE PACIFIC AND LOW PRESSURE TO THE SOUTH WILL CONTINUE NORTHERLY WINDS FOR THE NEXT 7 DAYS OR SO. THE PRESSURE GRADIENT WILL BE TIGHT ENOUGH TO GENERATE SMALL CRAFT WINDS THROUGH THURSDAY...ESPECIALLY BEYOND 20 NM FROM SHORE. THE GRADIENT WILL BE FAIRLY WEAK FRIDAY THROUGH NEXT MONDAY AND THE WIND DIRECTION WILL OCCASIONALLY HAVE MORE OF A WESTERLY COMPONENT. THE SEAS WILL BE DRIVEN BY THE LOCAL WINDS MAKING WIND WAVES AND FRESH SWELL DIFFICULT TO DISTINGUISH AND HAVE COMBINED THE SEAS THROUGH SATURDAY. THE WINDS WILL BE STEEP AT TIMES AND WARRANT SMALL CRAFT ADVISORIES. TJ && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 AM PDT THURSDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR FROM 10 TO 60 NM. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM NOON WEDNESDAY TO 11 AM PDT THURSDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM. SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO TO FLORENCE OR OUT 10 NM. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM PDT WEDNESDAY FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM. && $$ MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
921 PM EDT WED JUL 9 2014 .SYNOPSIS... A FRONTAL BOUNDARY WILL PUSH THROUGH THE AREA TONIGHT AND REMAINS IN PLACE THURSDAY BEFORE WASHING OUT BY FRIDAY. WEAK HIGH PRESSURE WILL RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE AREA EARLY NEXT WEEK. && .NEAR TERM /THROUGH THURSDAY/... AS OF 915 PM...A BAND OF SHOWERS AND THUNDERSTORMS WAS DRIFTING EAST ACROSS THE NC MTNS. LATEST MESOSCALE ANALYSIS INDICATED THAT CAPE VALUES ALONG AND AHEAD OF THE CONVECTION RANGED FROM 500-1000 J/KG WITH LITTLE TO NO CIN. HOWEVER...CIN IS ANTICIPATED TO INCREASE ACROSS THE REGION OVER THE NEXT TWO HOURS. I WILL UPDATE THE FORECAST TO ACCOUNT FOR THE RECENT COVERAGE AND TIME THE PLACEMENT AND DECREASING COVERAGE FOR THE REST OF THIS EVENING. AS OF 745 PM...WIDELY SCATTERED SHRA/TSRA REMAINED ACROSS THE FORECAST AREA. I WILL UPDATE THE FORECAST TO LOWER POPS ACROSS THE I-77 CORRIDOR...KEEP CHC POPS ELSEWHERE. I WILL ALSO INCREASE THE MENTION OF FOG ACROSS THE REGION LATE TONIGHT. AS OF 530 PM...A LARGE CLUSTER OF THUNDERSTORMS WAS PUSHING ACROSS THE I-77 CORRDIOR. I WILL UPDATE THE FORECAST TO INCREASE POPS OVER THE NEXT TWO HOURS ACROSS THE CLT METRO AREA. OUTFLOW GOVERNED TEMPERATURES WILL REMAIN CHALLENGING THROUGH THE EVENING...I WILL UPDATE WITH OBS. AT 215PM...MOST THUNDERSTORM COVERAGE AT MID AFTERNOON IS ACROSS THE SOUTHERN UPSTATE EASTWARD INTO NC. NUMEROUS STORMS DEVELOPED IN A DIFFERENTIAL HEATING AXIS CREATED BY CLOUD COVER TO NORTH EARLIER TODAY. PLUS THE LEE TROF HAS PROVIDED SOME LOW LEVEL CONVERGENCE. AN UPPER SHORT WAVE DEPICTED BY THE RAP IS ALSO CROSSING THE AREA. SHOULD SEE SOME ADDITIONAL DEVELOPMENT ACROSS THE NC MOUNTAINS/FOOTHILLS PER CAMS SO WILL CONTINUE WITH SCT TYPE POPS THOSE AREAS. SHOULD SEE THE COVERAGE OF CONVECTION WANE THIS EVENING AS S/W MOVES TO THE E. HOWEVER...A COLD FRONT JUST WEST OF THE APPALACHIANS IS FORECAST TO MOVE INTO THE NC MOUNTAINS THIS EVENING WHICH COULD KICK OFF SOME ADDITIONAL SHOWERS/THUNDERSTORMS...SO WILL SHOW AN UPTICK IN POPS OVER THE WEST THIS EVENING AGAIN. THE 12Z GFS SEEMS TO HAVE SOME CONVECTIVE FEEDBACK OVER FAR WESTERN NC IN THE 00Z-06Z TIMEFRAME AND WILL NOT BUY INTO THE HIGH GFS QPF DEPICTED THERE. ON THU...THE FRONT IS FORECAST TO REACH THE PIEDMONT. THE MODELS DEPICT A WEAK WAVE DEVELOPING ON THE BOUNDARY WHICH SHOULD TEND TO ENHANCE THE COVERAGE NEAR IT. PLUS...ANOTHER WEAK SHORT WAVE IS FORECAST TO CROSS THE AREA. HENCE...WILL STAY WITH THE IDEA OF SCT-NUMEROUS SHOWERS/STORMS ACROSS THE PIEDMONT DURING THE AFTERNOON...WITH LOWER POPS TO THE NORTH. SOUNDINGS LOOK MORE SATURATED WITH LESS DCAPE...SO DO NOT EXPECT MUCH IN THE WAY OF A SEVERE THREAT. MAX TEMPS ARE FORECAST TO BE ABOUT A CATEGORY BELOW CLIMO. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...STRETCHING NORTHEASTWARD INTO CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE ONGOING AS HEATING WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO THE SURFACE BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID CONVECTION. MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE LIFTING TO THE NORTHEAST ALLOWING H5 HEIGHTS TO RISE. POPS WILL TAPER DOWN DUE TO RISING HEIGHTS ALOFT AND HEATING LOSS INTO THE OVERNIGHT HOURS OF FRIDAY MORNING. LATEST GUIDANCE INDICATES POTENTIAL WEAK MESOLOW DEVELOPMENT ALONG THE FL PANHANDLE ON FRIDAY MORNING ALLOWING FOR ENHANCED SOUTHEASTERLY FLOW INTO THE CAROLINAS. THIS COMBINED WITH FLOW AROUND THE WESTERN ATLANTIC SURFACE RIDGE WILL ALLOW THE STALLED FRONTAL BOUNDARY TO GRADUALLY LIFT NORTHWARD TOWARDS THE CWFA INTO THE LATE AFTERNOON HOURS. MOISTURE CONVERGENCE ALONG THIS BOUNDARY WILL PROVIDE A FOCUS FOR CONVECTION ACROSS THE NC/SC PIEDMONT WHERE STEEPENING LAPSE RATES AND INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG. THUS WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND ALSO ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE FORECAST AREA BEFORE DIURNAL COOLING WARRANTS TAPERED POPS ACROSS THE ENTIRE REGION FOR THE OVERNIGHT. SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 245 PM EDT TUE...THE LATEST GLOBAL MODELS CONTINUE TO INDICATE THAT UPPER H5 HEIGHTS WILL FALL ACROSS THE SOUTHEAST SAT NIGHT INTO SUN AS AN UPPER RIDGE OF HIGH AMPLIFIES OVER THE WESTERN CONUS WHILE AN UPPER LOW PRESSURE TROUGH APPROACHES THE GREAT LAKES REGION FROM SOUTH CENTRAL CANADA. THIS TROUGH IS EXPECTED TO SWING ACROSS THE EASTERN STATES MON THROUGH WED. AT THE SURFACE...BERMUDA HIGH WILL PERSIST THROUGH SUN BEFORE SHIFTING TO THE EAST BY EARLY MON AS A COLD FRONT APPROACHES FROM THE NW. THE FRONT IS EXPECTED TO CROSS THE AREA THROUGH MON NIGHT FOLLOWED BY ANOTHER FRONT ON TUE. THE FRONT WILL REMAIN SOUTH OF THE AREA WED AS A CONTINENTAL HIGH BUILDS IN FROM THE NW. AS FOR OUR SENSIBLE WEATHER...POPS REMAIN NEAR CLIMO EACH DAY GIVEN LITTLE TO NO CAPPING ALOFT AND SEASONABLY UNSTABLE AIRMASS DURING THE PEAK HEATING HOURS. TEMPERATES WILL REMAIN NEAR...OR A FEW DEGREES BELOW NORMAL THROUGH THE PERIOD. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... AT CLT...THE TERMINAL RECEIVED 0.15 INCHES THIS AFTERNOON...ENOUGH TO WET THE SOIL. THE CONCERN OVER THE WET GROUND IS THE POTENTIAL FORMATION OF FOG LATE TONIGHT. A COLD FRONT WILL SLOWLY APPROACH FROM THE NW TONIGHT...LEAVING CLT IN A PREFRONTAL ENVIRONMENT. THESE SITUATIONS COMMONLY RESULT IN AT LEAST A PERIOD OF MVFR FOG...I WILL TEMPO BETWEEN 11Z TO 13Z. WINDS WILL REMAIN LIGHT AND FROM VARYING DIRECTIONS...RESULTING FROM A LEE TROF AND WEAK FRONT. BASED ON CAMS...I WILL USE A PROB30 FOR TSRA BETWEEN 17Z TO 23Z. ELSEWHERE...AFTERNOON CONVECTION HAS EITHER DIRECTLY IMPACTED OR OCCURRING IN THE VICINITY OF ALL THE TERMINALS. BASED ON THE POSITION OF THE FRONT AND WET GROUND I WILL MENTION MVFR FOG AT ALL SITES...KAVL DOWN TO IFR. BY EARLY THURSDAY AFTERNOON...CONDITIONS WILL DESTABILIZE WITHIN A SFC TROF. I WILL HIGHLIGHT THE CONVECTION POTENTIAL WITH A LATE AFTERNOON PROB30 FOR ALL SITES. OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND MORNING VALLEY FOG EACH DAY. CONFIDENCE TABLE... 01-07Z 07-13Z 13-19Z 19-01Z KCLT HIGH 100% HIGH 97% HIGH 92% HIGH 92% KGSP HIGH 100% HIGH 88% HIGH 92% MED 78% KAVL HIGH 97% HIGH 81% HIGH 80% MED 73% KHKY HIGH 100% HIGH 100% HIGH 94% LOW 58% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 93% KAND HIGH 100% HIGH 86% HIGH 100% HIGH 93% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...LG/NED SHORT TERM...CDG LONG TERM...JOH/WIMBERLEY AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
752 PM EDT WED JUL 9 2014 .SYNOPSIS... A FRONTAL BOUNDARY WILL PUSH THROUGH THE AREA TONIGHT AND REMAINS IN PLACE THURSDAY BEFORE WASHING OUT BY FRIDAY. WEAK HIGH PRESSURE WILL RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE AREA EARLY NEXT WEEK. && .NEAR TERM /THROUGH THURSDAY/... AS OF 745 PM...WIDELY SCATTERED SHRA/TSRA REMAINED ACROSS THE FORECAST AREA. I WILL UPDATE THE FORECAST TO LOWER POPS ACROSS THE I-77 CORRIDOR...KEEP CHC POPS ELSEWHERE. I WILL ALSO INCREASE THE MENTION OF FOG ACROSS THE REGION LATE TONIGHT. AS OF 530 PM...A LARGE CLUSTER OF THUNDERSTORMS WAS PUSHING ACROSS THE I-77 CORRDIOR. I WILL UPDATE THE FORECAST TO INCREASE POPS OVER THE NEXT TWO HOURS ACROSS THE CLT METRO AREA. OUTFLOW GOVERNED TEMPERATURES WILL REMAIN CHALLENGING THROUGH THE EVENING...I WILL UPDATE WITH OBS. AT 215PM...MOST THUNDERSTORM COVERAGE AT MID AFTERNOON IS ACROSS THE SOUTHERN UPSTATE EASTWARD INTO NC. NUMEROUS STORMS DEVELOPED IN A DIFFERENTIAL HEATING AXIS CREATED BY CLOUD COVER TO NORTH EARLIER TODAY. PLUS THE LEE TROF HAS PROVIDED SOME LOW LEVEL CONVERGENCE. AN UPPER SHORT WAVE DEPICTED BY THE RAP IS ALSO CROSSING THE AREA. SHOULD SEE SOME ADDITIONAL DEVELOPMENT ACROSS THE NC MOUNTAINS/FOOTHILLS PER CAMS SO WILL CONTINUE WITH SCT TYPE POPS THOSE AREAS. SHOULD SEE THE COVERAGE OF CONVECTION WANE THIS EVENING AS S/W MOVES TO THE E. HOWEVER...A COLD FRONT JUST WEST OF THE APPALACHIANS IS FORECAST TO MOVE INTO THE NC MOUNTAINS THIS EVENING WHICH COULD KICK OFF SOME ADDITIONAL SHOWERS/THUNDERSTORMS...SO WILL SHOW AN UPTICK IN POPS OVER THE WEST THIS EVENING AGAIN. THE 12Z GFS SEEMS TO HAVE SOME CONVECTIVE FEEDBACK OVER FAR WESTERN NC IN THE 00Z-06Z TIMEFRAME AND WILL NOT BUY INTO THE HIGH GFS QPF DEPICTED THERE. ON THU...THE FRONT IS FORECAST TO REACH THE PIEDMONT. THE MODELS DEPICT A WEAK WAVE DEVELOPING ON THE BOUNDARY WHICH SHOULD TEND TO ENHANCE THE COVERAGE NEAR IT. PLUS...ANOTHER WEAK SHORT WAVE IS FORECAST TO CROSS THE AREA. HENCE...WILL STAY WITH THE IDEA OF SCT-NUMEROUS SHOWERS/STORMS ACROSS THE PIEDMONT DURING THE AFTERNOON...WITH LOWER POPS TO THE NORTH. SOUNDINGS LOOK MORE SATURATED WITH LESS DCAPE...SO DO NOT EXPECT MUCH IN THE WAY OF A SEVERE THREAT. MAX TEMPS ARE FORECAST TO BE ABOUT A CATEGORY BELOW CLIMO. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...STRETCHING NORTHEASTWARD INTO CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE ONGOING AS HEATING WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO THE SURFACE BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID CONVECTION. MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE LIFTING TO THE NORTHEAST ALLOWING H5 HEIGHTS TO RISE. POPS WILL TAPER DOWN DUE TO RISING HEIGHTS ALOFT AND HEATING LOSS INTO THE OVERNIGHT HOURS OF FRIDAY MORNING. LATEST GUIDANCE INDICATES POTENTIAL WEAK MESOLOW DEVELOPMENT ALONG THE FL PANHANDLE ON FRIDAY MORNING ALLOWING FOR ENHANCED SOUTHEASTERLY FLOW INTO THE CAROLINAS. THIS COMBINED WITH FLOW AROUND THE WESTERN ATLANTIC SURFACE RIDGE WILL ALLOW THE STALLED FRONTAL BOUNDARY TO GRADUALLY LIFT NORTHWARD TOWARDS THE CWFA INTO THE LATE AFTERNOON HOURS. MOISTURE CONVERGENCE ALONG THIS BOUNDARY WILL PROVIDE A FOCUS FOR CONVECTION ACROSS THE NC/SC PIEDMONT WHERE STEEPENING LAPSE RATES AND INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG. THUS WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND ALSO ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE FORECAST AREA BEFORE DIURNAL COOLING WARRANTS TAPERED POPS ACROSS THE ENTIRE REGION FOR THE OVERNIGHT. SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 245 PM EDT TUE...THE LATEST GLOBAL MODELS CONTINUE TO INDICATE THAT UPPER H5 HEIGHTS WILL FALL ACROSS THE SOUTHEAST SAT NIGHT INTO SUN AS AN UPPER RIDGE OF HIGH AMPLIFIES OVER THE WESTERN CONUS WHILE AN UPPER LOW PRESSURE TROUGH APPROACHES THE GREAT LAKES REGION FROM SOUTH CENTRAL CANADA. THIS TROUGH IS EXPECTED TO SWING ACROSS THE EASTERN STATES MON THROUGH WED. AT THE SURFACE...BERMUDA HIGH WILL PERSIST THROUGH SUN BEFORE SHIFTING TO THE EAST BY EARLY MON AS A COLD FRONT APPROACHES FROM THE NW. THE FRONT IS EXPECTED TO CROSS THE AREA THROUGH MON NIGHT FOLLOWED BY ANOTHER FRONT ON TUE. THE FRONT WILL REMAIN SOUTH OF THE AREA WED AS A CONTINENTAL HIGH BUILDS IN FROM THE NW. AS FOR OUR SENSIBLE WEATHER...POPS REMAIN NEAR CLIMO EACH DAY GIVEN LITTLE TO NO CAPPING ALOFT AND SEASONABLY UNSTABLE AIRMASS DURING THE PEAK HEATING HOURS. TEMPERATES WILL REMAIN NEAR...OR A FEW DEGREES BELOW NORMAL THROUGH THE PERIOD. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... AT CLT...THE TERMINAL RECEIVED 0.15 INCHES THIS AFTERNOON...ENOUGH TO WET THE SOIL. THE CONCERN OVER THE WET GROUND IS THE POTENTIAL FORMATION OF FOG LATE TONIGHT. A COLD FRONT WILL SLOWLY APPROACH FROM THE NW TONIGHT...LEAVING CLT IN A PREFRONTAL ENVIRONMENT. THESE SITUATIONS COMMONLY RESULT IN AT LEAST A PERIOD OF MVFR FOG...I WILL TEMPO BETWEEN 11Z TO 13Z. WINDS WILL REMAIN LIGHT AND FROM VARYING DIRECTIONS...RESULTING FROM A LEE TROF AND WEAK FRONT. BASED ON CAMS...I WILL USE A PROB30 FOR TSRA BETWEEN 17Z TO 23Z. ELSEWHERE...AFTERNOON CONVECTION HAS EITHER DIRECTLY IMPACTED OR OCCURRING IN THE VICINITY OF ALL THE TERMINALS. BASED ON THE POSITION OF THE FRONT AND WET GROUND I WILL MENTION MVFR FOG AT ALL SITES...KAVL DOWN TO IFR. BY EARLY THURSDAY AFTERNOON...CONDITIONS WILL DESTABILIZE WITHIN A SFC TROF. I WILL HIGHLIGHT THE CONVECTION POTENTIAL WITH A LATE AFTERNOON PROB30 FOR ALL SITES. OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND MORNING VALLEY FOG EACH DAY. CONFIDENCE TABLE... 00-06Z 06-12Z 12-18Z 18-24Z KCLT HIGH 100% HIGH 95% HIGH 95% HIGH 90% KGSP HIGH 100% HIGH 91% HIGH 100% MED 73% KAVL HIGH 95% HIGH 86% HIGH 82% HIGH 80% KHKY HIGH 100% HIGH 100% HIGH 100% MED 61% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 93% KAND HIGH 100% HIGH 91% HIGH 100% HIGH 93% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...LG/NED SHORT TERM...CDG LONG TERM...JOH/WIMBERLEY AVIATION...NED
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
319 PM CDT TUE JUL 8 2014 .DISCUSSION... CURRENTLY...AN OUTFLOW BOUNDARY FROM THE EARLIER MCS KICKED OFF ISOLD TO SCT TSTMS THAT ARE NOW MOVING OFF INTO ALABAMA. OTRW THINGS ARE FAIRLY QUIET WITH CONVECTIVE DEBRIS CLOUDINESS ACROSS THE REGION. THE AIRMASS HAS BEEN SLOWLY RECOVERING ACROSS THE NORTH AS TEMPS CLIMB BACK INTO THE 80S WITH DEWPOINTS IN THE LOWER 70S. THE APPROACHING COLD FRONT IS LOCATED OVER SOUTHERN MISSOURI. TONIGHT...THE COLD FRONT WILL PUSH INTO NORTHERN SECTIONS OF THE MIDSOUTH THIS EVENING. THE AIRMASS WILL CONTINUE TO RECOVER OVER THE NEXT COUPLE OF HOURS AND SHOWERS AND THUNDERSTORMS WILL DEVELOP ACROSS NORTHERN SECTIONS OF THE MIDSOUTH AS THE FRONT MOVES IN. THE 16Z HRRR DEPICTS THIS SCENARIO WITH CONVECTION PUSHING SOUTHWARD WITH THE FRONT THROUGH THE NIGHT. A FEW STRONG TO SEVERE STORMS WITH LOCALLY HEAVY RAIN ARE POSSIBLE AS THE FRONT PUSHES THROUGH. THE BETTER CHANCE FOR SEVERE STORMS WILL BE NORTH OF THE MS/TN BORDER WHERE MID LEVEL WINDS ARE STRONGER WHICH WILL AID STORM ORGANIZATION. CURRENT HWO HANDLES THIS WELL. RAIN CHANCE WILL SHIFT SOUTH AFTER MIDNIGHT AS THE FRONT MOVES INTO NORTH MISSISSIPPI. WEDNESDAY AND THURSDAY...THE FRONT WILL STALL OVER NORTH MISSISSIPPI OR JUST TO THE SOUTH AND GRADUALLY WEAKEN. THERE WILL BE SCT-NUMEROUS STORMS OVER NORTH MISSISSIPPI BY WED AFTERNOON AND SOME OF THESE STORMS COULD BE STRONG TO SEVERE. HIGH PRESSURE BUILDING INTO NORTHERN SECTIONS OF THE MID SOUTH WILL RESULT IN A PLEASANT DAY WITH HIGHS IN THE 80S. RAIN CHANCES WILL DIMINISH ACROSS NORTH MISSISSIPPI WED NIGHT INTO THURSDAY WITH DRY WEATHER ACROSS NORTHERN SECTIONS. HIGHS IN THE UPPER 80S TO AROUND 90. FRIDAY INTO SUNDAY...UPPER RIDGE STARTS TO BUILD INTO THE AREA WITH WARMING TEMPS. LOW SUMMERTIME POPS. DID NOT GET AS AGGRESSIVE AS THE MEX WITH RESPECT TO HIGH TEMPS. MONDAY AND TUESDAY...UPPER TROF MOVING INTO THE GREAT LAKES WILL PUSH ANOTHER FRONT ACROSS THE MIDSOUTH WITH CHANCE FOR SHOWERS AND THUNDERSTORMS. COOLER BY TUESDAY. SJM && .AVIATION... VFR CONDITIONS SHOULD PERSIST FOR MOST OF THE FORECAST PERIOD. A FEW SHOWERS WERE WEAKENING AS THEY MOVE ACROSS NORTHEAST ARKANSAS. ANOTHER ROUND IF THUNDERSTORMS IS EXPECTED TO START THIS EVENING AND CONTINUE INTO THE OVERNIGHT HOURS. THESE THUNDERSTORMS MAY PRODUCE MVFR VISIBILITIES AT TIMES. WINDS WILL BE MAINLY SOUTHWEST AT 5 TO 10 KNOTS THIS AFTERNOON BEFORE GRADUALLY SHIFTING TO THE WEST THIS EVENING AND TO THE NORTHWEST BY WEDNESDAY MORNING. ARS && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1236 PM CDT TUE JUL 8 2014 .DISCUSSION... UPDATED FOR THE 18Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 1102 AM CDT TUE JUL 8 2014/ DISCUSSION... THE REMNANTS OF THE MCS THAT MOVED ACROSS THE ENTIRE STATE OF MISSOURI IS NOW EXITING THE FORECAST AREA NEAR THE TN RIVER. ANOTHER MCS THAT FORMED OVER SOUTHERN MISSOURI THIS MORNING IS WEAKENING ACROSS NE ARKANSAS. THESE SYSTEMS HAVE MOVED WELL OUT IN ADVANCE OF THE COLD FRONT AND HAVE STABILIZED THE AIRMASS ACROSS THE NORTHERN HALF OF THE MIDSOUTH. AS A RESULT OF THE MORNING CLOUDS AND PRECIP HAVE KNOCKED DOWN HIGH TEMPS ACROSS THE NORTHERN HALF OF THE FORECAST AREA BY A COUPLE OF DEGREES. WILL HAVE TO SEE HOW THE AIRMASS RECOVERS THIS AFTERNOON AS THE ACTUAL COLD FRONT...CURRENTLY LOCATED OVER SOUTHERN MISSOURI...APPROACHES. THE 13Z HRRR IS NOT VERY BULLISH. WILL CONSIDER REDUCING POPS ACROSS THE NORTH FOR THIS AFTERNOON. SJM PREV DISCUSSION... /ISSUED 533 AM CDT TUE JUL 8 2014/ UPDATE... OUTFLOW FROM A DECAYING MCS OVERNIGHT HAS PUSHED A QUICK MOVING LINE OF NUMEROUS SHOWERS AND THUNDERSTORMS INTO THE FORECAST AREA. HAVE UPPED POPS TO LIKELYS ALONG AND NORTH OF THE I-40 CORRIDOR...WITH CHANCE POPS ACROSS NORTH MISSISSIPPI AND ALSO INCREASED CLOUD COVER. THESE SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DECREASE IN COVERAGE AND INTENSITY BY LATE MORNING BEFORE REDEVELOPMENT LATER THIS AFTERNOON. AC3 PR EV DISCUSSION... /ISSUED 436 AM CDT TUE JUL 8 2014/ DISCUSSION... CURRENTLY... AS OF 4AM...TEMPERATURES ARE QUITE WARM ACROSS THE REGION WITH READINGS IN THE MID TO UPPER 70S AREA WIDE. SOME SHOWERS AND THUNDERSTORMS WERE ALREADY MOVING INTO THE NORTHERN PARTS OF THE FORECAST AREA...SPAWNED FROM A SLOWLY DECAYING MACS LOCATED OVER THE SOUTHERN MISSOURI AND NORTHERN ARKANSAS BORDER. CONVECTION SHOULD BEGIN TO DIMINISH AS WE APPROACH SUNRISE AS THE OUTFLOW OUTPACES THE MAIN CONVECTION. LATEST SURFACE ANALYSIS PLACES A COLD FRONT FROM NORTHERN ILLINOIS...BACK THROUGH SAINT LOUIS...AND INTO NORTHWEST ARKANSAS. SHORT TERM...TODAY THROUGH THURSDAY... THE AFOREMENTIONED COLD FRONT WILL CONTINUE TO MOVE SOUTHEAST INTO THE FORECAST AREA LATER THIS AFTERNOON WITH THE AID OF A SHORTWAVE TROUGH LOCATED NEAR THE IOWA/MISSOURI BORDER. SOME MORNING CONVECTION CANNOT BE RULED OUT...MAINLY NORTH OF THE I-40 CORRIDOR...WHERE A FEW OUTFLOW BOUNDARIES MAY INTERACT WITH A RELATIVELY UNSTABLE AIR MASS. BY THIS AFTERNOON...SB CAPE VALUES ARE EXPECTED TO BE IN EXCESS OF 2500 J/KG...LI`S -8 TO -10...AND MID LEVEL LAPSE RATES AROUND 7 C/KM. 0-6 KM BULK SHEAR WILL BE WEAK AT 20 KNOTS OR SO...HOWEVER THESE PARAMETERS WILL STILL SUPPORT AT LEAST A FEW STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO THE LATE EVENING HOURS. IN ADDITION...PRECIPITATELY WATER VALUES WILL BE AROUND 2.0 INCHES. THE PRIMARY THREATS WILL BE DAMAGING WINDS...LARGE HAIL...AND FLASH FLOODING. THE FRONT IS EXPECTED TO STALL OUT ACROSS NORTH MISSISSIPPI BY WEDNESDAY AFTERNOON. ALONG AND SOUTH OF WHERE THE FRONT ACTUALLY STALLS...ANOTHER POTENTIAL FOR A FEW STRONG TO SEVERE THUNDERSTORMS WILL EXIST IN THE WARM SECTOR DURING THE AFTERNOON HOURS WITH THE SAME PREVIOUSLY MENTIONED THREATS. UNDERCUT GUIDANCE BY A FEW DEGREES FOR WEDNESDAY DUE TO THE ABUNDANT CLOUD COVER AND ONGOING CONVECTION. BY THURSDAY...THE FRONT WILL PUSH A LITTLE FURTHER SOUTH...AND CONTINUE TO SUPPORT AT LEAST AN ISOLATED CHANCE OF SHOWERS AND THUNDERSTORMS IN THE EXTREME SOUTHERN PART OF OUR FORECAST AREA. SURFACE HIGH PRESSURE IS EXPECTED TO BUILD INTO THE NORTHERN PORTIONS OF THE MID-SOUTH BY THURSDAY NIGHT PUTTING AN END TO THE RAIN CHANCES IN THAT AREA. LONG TERM...FRIDAY THROUGH EARLY NEXT WEEK... MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT THAT THE FRONT WILL LIKELY LIFT NORTH ON FRIDAY AFTERNOON AS A WARM FRONT AS SURFACE HIGH PRESSURE LIFTS OUT TO THE NORTHEAST. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE DURING THE DAY...BUT SHOULD ONLY WARRANT A MENTION OF SLIGHT POPS ACROSS THE MAJORITY OF THE REGION. BY THIS WEEKEND...MODEL GUIDANCE IS STILL NOT IN VERY GOOD AGREEMENT ABOUT THE UPPER LEVEL PATTERN OVER MID-SOUTH...HOWEVER THEY DO AGREE ON TEMPERATURES REACHING INTO THE LOW TO MID 90S. THE GFS IS OPTIMISTIC ABOUT UPPER LEVEL RIDGING...WHILE THE EURO KEEPS US IN NORTHWEST FLOW ALOFT THROUGH EARLY NEXT WEEK. SINCE THE EURO IS MOST CONSISTENT IN THE MID TERM...WILL CONTINUE TO CARRY AT LEAST THE THREAT OF DAYTIME DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS. BY EARLY NEXT WEEK...ANOTHER COLD FRONT APPEARS TO DROP INTO THE MID-SOUTH ON MONDAY EVENING INTO TUESDAY. FOR NOW...WILL ADVERTISE SLIGHT CHANCE POPS THROUGH THAT TIME FRAME. AC3 && .AVIATION... VFR CONDITIONS SHOULD PERSIST FOR MOST OF THE FORECAST PERIOD. A FEW SHOWERS WERE WEAKENING AS THEY MOVE ACROSS NORTHEAST ARKANSAS. ANOTHER ROUND IF THUNDERSTORMS IS EXPECTED TO START THIS EVENING AND CONTINUE INTO THE OVERNIGHT HOURS. THESE THUNDERSTORMS MAY PRODUCE MVFR VISIBILITIES AT TIMES. WINDS WILL BE MAINLY SOUTHWEST AT 5 TO 10 KNOTS THIS AFTERNOON BEFORE GRADUALLY SHIFTING TO THE WEST THIS EVENING AND TO THE NORTHWEST BY WEDNESDAY MORNING. ARS && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1102 AM CDT TUE JUL 8 2014 .DISCUSSION... THE REMNANTS OF THE MCS THAT MOVED ACROSS THE ENTIRE STATE OF MISSOURI IS NOW EXITING THE FORECAST AREA NEAR THE TN RIVER. ANOTHER MCS THAT FORMED OVER SOUTHERN MISSOURI THIS MORNING IS WEAKENING ACROSS NE ARKANSAS. THESE SYSTEMS HAVE MOVED WELL OUT IN ADVANCE OF THE COLD FRONT AND HAVE STABILIZED THE AIRMASS ACROSS THE NORTHERN HALF OF THE MIDSOUTH. AS A RESULT OF THE MORNING CLOUDS AND PRECIP HAVE KNOCKED DOWN HIGH TEMPS ACROSS THE NORTHERN HALF OF THE FORECAST AREA BY A COUPLE OF DEGREES. WILL HAVE TO SEE HOW THE AIRMASS RECOVERS THIS AFTERNOON AS THE ACTUAL COLD FRONT...CURRENTLY LOCATED OVER SOUTHERN MISSOURI...APPROACHES. THE 13Z HRRR IS NOT VERY BULLISH. WILL CONSIDER REDUCING POPS ACROSS THE NORTH FOR THIS AFTERNOON. SJM && PREV DISCUSSION... /ISSUED 533 AM CDT TUE JUL 8 2014/ UPDATE... OUTFLOW FROM A DECAYING MCS OVERNIGHT HAS PUSHED A QUICK MOVING LINE OF NUMEROUS SHOWERS AND THUNDERSTORMS INTO THE FORECAST AREA. HAVE UPPED POPS TO LIKELYS ALONG AND NORTH OF THE I-40 CORRIDOR...WITH CHANCE POPS ACROSS NORTH MISSISSIPPI AND ALSO INCREASED CLOUD COVER. THESE SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DECREASE IN COVERAGE AND INTENSITY BY LATE MORNING BEFORE REDELOPMENT LATER THIS AFTERNOON. AC3 PREV DISCUSSION... /ISSUED 436 AM CDT TUE JUL 8 2014/ DISCUSSION... CURRENTLY... AS OF 4AM...TEMPERATURES ARE QUITE WARM ACROSS THE REGION WITH READINGS IN THE MID TO UPPER 70S AREA WIDE. SOME SHOWERS AND THUNDERSTORMS WERE ALREADY MOVING INTO THE NORTHERN PARTS OF THE FORECAST AREA...SPAWNED FROM A SLOWLY DECAYING MCS LOCATED OVER THE SOUTHERN MISSOURI AND NORTHERN ARKANSAS BORDER. CONVECTION SHOULD BEGIN TO DIMINISH AS WE APPROACH SUNRISE AS THE OUTFLOW OUTPACES THE MAIN CONVECTION. LATEST SURFACE ANALYSIS PLACES A COLD FRONT FROM NORTHERN ILLINOIS...BACK THROUGH SAINT LOUIS...AND INTO NORTHWEST ARKANSAS. SHORT TERM...TODAY THROUGH THURSDAY... THE AFOREMENTIONED COLD FRONT WILL CONTINUE TO MOVE SOUTHEAST INTO THE FORECAST AREA LATER THIS AFTERNOON WITH THE AID OF A SHORTWAVE TROUGH LOCATED NEAR THE IOWA/MISSOURI BORDER. SOME MORNING CONVECTION CANNOT BE RULED OUT...MAINLY NORTH OF THE I-40 CORRIDOR...WHERE A FEW OUTFLOW BOUNDARIES MAY INTERACT WITH A RELATIVELY UNSTABLE AIRMASS. BY THIS AFTERNOON...SBCAPE VALUES ARE EXPECTED TO BE IN EXCESS OF 2500 J/KG...LI`S -8 TO -10...AND MID LEVEL LAPSE RATES AROUND 7 C/KM. 0-6 KM BULK SHEAR WILL BE WEAK AT 20 KNOTS OR SO...HOWEVER THESE PARAMETERS WILL STILL SUPPORT AT LEAST A FEW STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO THE LATE EVENING HOURS. IN ADDITION...PRECIPITABLE WATER VALUES WILL BE AROUND 2.0 INCHES. THE PRIMARY THREATS WILL BE DAMAGING WINDS...LARGE HAIL...AND FLASH FLOODING. THE FRONT IS EXPECTED TO STALL OUT ACROSS NORTH MISSISSIPPI BY WEDNESDAY AFTERNOON. ALONG AND SOUTH OF WHERE THE FRONT ACTUALLY STALLS...ANOTHER POTENTIAL FOR A FEW STRONG TO SEVERE THUNDERSTORMS WILL EXIST IN THE WARM SECTOR DURING THE AFTERNOON HOURS WITH THE SAME PREVIOUSLY MENTIONED THREATS. UNDERCUT GUIDANCE BY A FEW DEGREES FOR WEDNESDAY DUE TO THE ABUNDANT CLOUD COVER AND ONGOING CONVECTION. BY THURSDAY...THE FRONT WILL PUSH A LITTLE FURTHER SOUTH...AND CONTINUE TO SUPPORT AT LEAST AN ISOLATED CHANCE OF SHOWERS AND THUNDERSTORMS IN THE EXTREME SOUTHERN PART OF OUR FORECAST AREA. SURFACE HIGH PRESSURE IS EXPECTED TO BUILD INTO THE NORTHERN PORTIONS OF THE MID-SOUTH BY THURSDAY NIGHT PUTTING AN END TO THE RAIN CHANCES IN THAT AREA. LONG TERM...FRIDAY THROUGH EARLY NEXT WEEK... MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT THAT THE FRONT WILL LIKELY LIFT NORTH ON FRIDAY AFTERNOON AS A WARM FRONT AS SURFACE HIGH PRESSURE LIFTS OUT TO THE NORTHEAST. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE DURING THE DAY...BUT SHOULD ONLY WARRANT A MENTION OF SLIGHT POPS ACROSS THE MAJORITY OF THE REGION. BY THIS WEEKEND...MODEL GUIDANCE IS STILL NOT IN VERY GOOD AGREEMENT ABOUT THE UPPER LEVEL PATTERN OVER MID-SOUTH...HOWEVER THEY DO AGREE ON TEMPERATURES REACHING INTO THE LOW TO MID 90S. THE GFS IS OPTIMISTIC ABOUT UPPER LEVEL RIDGING...WHILE THE EURO KEEPS US IN NORTHWEST FLOW ALOFT THROUGH EARLY NEXT WEEK. SINCE THE EURO IS MOST CONSISTENT IN THE MID TERM...WILL CONTINUE TO CARRY AT LEAST THE THREAT OF DAYTIME DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS. BY EARLY NEXT WEEK...ANOTHER COLD FRONT APPEARS TO DROP INTO THE MID-SOUTH ON MONDAY EVENING INTO TUESDAY. FOR NOW...WILL ADVERTISE SLIGHT CHANCE POPS THROUGH THAT TIME FRAME. AC3 && .AVIATION... 12Z TAF CYCLE A LINE OF THUNDERSTORMS CONTINUES TO MOVE SOUTHEAST AND WILL IMPACT BOTH KMEM AND KMKL THROUGH 13Z. STRONG WIND GUSTS UP TO 35 KTS WILL BE POSSIBLE AS THE LINE MOVES THROUGH. THIS LINE OF STORMS WILL BREAK UP OVER THE NEXT HOUR OR TWO AND UNLIKELY TO REACH KTUP. ADDITIONAL STORMS WILL REDEVELOP LATER THIS AFTERNOON AND EVENING AND SHOULD IMPACT ALL SITES. PREVAILING WINDS SHOULD BE FROM THE SOUTHWEST AROUND 10-12 KTS OUTSIDE OF THUNDERSTORMS. VFR CIGS AND VSBYS SHOULD REMAIN THE PREDOMINATE CONDITION...WITH ONLY BRIEF LOWERING POSSIBLE IN STRONGER THUNDERSTORMS. WINDS SHOULD DROP BELOW 7 KTS TONIGHT AT ALL TERMINALS. CONVECTIVE COVERAGE SHOULD DIMINISH LATER THIS EVENING AND OVERNIGHT...BUT IS SOMEWHAT UNCERTAIN AT THIS TIME AND WILL BE MODULATED BY MESOSCALE PROCESSES. JLH && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1111 PM CDT MON JUL 7 2014 .UPDATE... MCS WHICH MOVED ACROSS FAR NORTHERN AREAS EARLIER HAS NOW WEAKENED CONSIDERABLY. JUST A FEW SHOWERS IS ALL THAT REMAINS ACROSS OUR PLATEAU. HRRR AND MODEL DATA HANDLED THIS QUITE WELL. A CURRENT LOOK AT THE HRRR DOES SHOW REDEVELOPMENT TOWARD THE 12Z-15Z TIMEFRAME WITH THE ACTIVITY THAT IS CURRENTLY LOCATED OVER MO. WILL GO AHEAD AND LOWER POPS BUT STILL KEEP A 20-30 PERCENT CHANCE GOING ACROSS THE NORTH. DUE TO TIMING...WILL NEED TO KEEP THE POPS ON THE LOW SIDE. TEMPS STILL LOOK TO BE IN GOOD SHAPE BUT WILL ADD A FEW EXTRA CLOUDS ACROSS OUR NORTHERN AREAS. && .PREV DISCUSSION... /ISSUED 732 PM CDT MON JUL 7 2014/ UPDATE...FOR 00Z TAFS. AVIATION... CHANGES IN THE WORKS THIS PERIOD AS UPPER TROUGH AND WEAK FRONTAL BOUNDARY GET INTO THE PICTURE. DEVELOPMENT UPSTREAM EXPECTED TO DECREASE TONIGHT BUT SAG DOWN INTO THE AREA LATER. SHWRS/STMS THEN EXPECTED TO INCREASE EARLY TUE AND REMAIN FAIRLY WIDESPREAD WELL INTO TUE EVE. ALL SITES HAVE GOOD CHANCE OF BEING AFFECTED... WHICH WILL REDUCE CIGS/VSBYS. BEST CHANCE LARGELY AFTER 15Z TUE. WINDS ALSO EXPECTED TO GUST 20+KTS BY 15Z. PREV DISCUSSION... /ISSUED 627 PM CDT MON JUL 7 2014/ DISCUSSION... MCS CURRENTLY NOT TOO FAR OFF TO THE NORTH WITH THE CONVECTION AS FAR SOUTH AS HOPKINS AND MUHLENBERG COUNTIES. HRRR AND MODEL DATA SUGGESTS THAT THIS CONVECTION WILL WEAKEN QUICKLY AS IT APPROACHES. HOWEVER...THOUGH SOME WEAKENING IS EXPECTED...I FEEL AS IF POPS ACROSS THE NORTH MAY NEED TO BE INCREASED SLIGHTLY. SOME WIND DAMAGE HAS ALREADY OCCURRED WITH A FEW OF THESE STORMS EARLIER THIS AFTERNOON. LATEST MID LEVEL FLOW PATTERN SUGGESTS THAT THE STORMS WILL ENCOUNTER LESS FAVORABLE SHEAR AS THEY MOVE SOUTHWARD...SO BOTH THE INTENSITY AND COVERAGE SHOULD BE ON THE DECREASE. OTW...TOWARD 12Z...WE`LL SEE AN INCREASE IN ATMOSPHERIC MOISTURE WITH SOME ADDITIONAL DEVELOPMENT CONTINUING TO MOVE SOUTHWARD. FOR THE FCST...WILL LEAN TOWARD INCREASING POPS SOME OVERNIGHT. WHEN COMBINING THE CURRENT ACTIVITY WITH ADDITIONAL FAVORABLE CONVECTIVE CONDITIONS TOWARD 12Z...WILL NEED TO GO A LITTLE HIGHER THAN JUST A SLIGHT CHANCE. REMAINDER OF THE FCST APPEARS TO BE OK. WILL ADD A FEW EXTRA CLOUDS ACROSS THE NORTH. OVERNIGHT LOWS SHOULD BE WARMER TONIGHT AS DEWPOINT VALUES WERE HIGHER TODAY. UPDATE OUT SHORTLY. PREV DISCUSSION... /ISSUED 327 PM CDT MON JUL 7 2014/ DISCUSSION... HEAT AND MOISTURE HAVE RETURNED IN EARNEST TODAY WITH TEMPERATURES CURRENTLY RANGING FROM THE LOW 80S ON THE PLATEAU TO UPPER 80S/LOW 90S ELSEWHERE...ALONG WITH DEWPOINTS UP INTO THE 60S AND LOW 70S. WEAK SHORTWAVE TROUGH ALOFT NOTED ON WATER VAPOR IMAGERY HAS PROVIDED ENOUGH LIFT TO SPAWN SOME ISOLATED SHOWERS AND THUNDERSTORMS OVER SOUTHWEST ZONES THIS AFTERNOON. HAVE INCLUDED A PRE FIRST PERIOD FOR WESTERN ZONES ON ACCOUNT OF THIS DIURNALLY DRIVEN ACTIVITY. OTHERWISE...ATTENTION TURNS TO THE NORTH AS CONVECTION IS BLOSSOMING ALONG A WEAK COLD FRONT ADVANCING SOUTHWARD THROUGH THE MIDWEST. 12Z MODELS INDICATE THIS ACTIVITY...ALONG WITH AN EXPECTED MCS DEVELOPING NEAR KANSAS CITY...WILL MAKE A RUN AT OUR NORTHWEST ZONES LATE TONIGHT. CONSIDERABLE UNCERTAINTY ON HOW FAR THIS ACTIVITY WILL SURVIVE AND AT WHAT INTENSITY...BUT WARRANTS LOW CHANCE POPS OVER NORTHERN ZONES ESPECIALLY TOWARDS SUNRISE TUESDAY MORNING. CANNOT COMPLETELY RULE OUT A STRONG OR POSSIBLY EVEN SEVERE STORM IF CONVECTION CAN SURVIVE THIS FAR SOUTH AS SPC HAS INDICATED IN THEIR DAY 1 OUTLOOK...BUT FAR BETTER CHANCE FOR STRONG TO SEVERE STORMS WILL BE WELL OFF TO OUR NORTH. ON TUESDAY...REMNANTS OF MCS SHOULD WEAKEN/DISSIPATE WITH ALL GUIDANCE INDICATING RENEWED CONVECTIVE DEVELOPMENT ALONG FRONTAL BOUNDARY SITUATED NEAR THE OHIO RIVER TUESDAY AFTERNOON. 12Z GUIDANCE HAS SPED UP ARRIVAL OF THIS ACTIVITY WITH STORMS LIKELY REACHING THE KY BORDER BY LATE AFTERNOON...THEN MOVING ACROSS THE MID STATE THROUGH THE EVENING BEFORE WEAKENING LATE TUESDAY NIGHT. HAVE KEPT POPS ABOVE GUIDANCE IN THE LIKELY TO CATEGORICAL RANGE DUE TO CONFIDENCE IN THIS SCENARIO. 12Z GFS/NAM FORECAST SOUNDINGS ARE MORE ROBUST WITH INSTABILITY VS THIS TIME YESTERDAY SHOWING LI VALUES AS LOW AS -7 TO -8 ALONG WITH SBCAPE AS HIGH AS 3000 J/KG. THESE PARAMETERS ALONG WITH DEEP LAYER SHEAR AROUND 40 KNOTS AND PWAT VALUES UP TO 2 INCHES SUGGESTS STRONG TO SEVERE STORMS WILL BE POSSIBLE WITH DAMAGING WINDS AND LOCALLY HEAVY RAINFALL THE MAIN THREATS...WITH HIGHEST RISK ALONG AND NORTH OF I-40 LATE TUESDAY AFTERNOON INTO TUESDAY EVENING. HOWEVER...SPC HAS HIGHLIGHTED THE ENTIRE MID STATE IN A SLIGHT RISK FOR SEVERE STORMS ON THEIR DAY 2 OUTLOOK. WEAK COLD FRONT WILL SHIFT SLOWLY SOUTHWARD THROUGH THE MID STATE DURING THE DAY ON WEDNESDAY...WITH ADDITIONAL SHOWER AND THUNDERSTORM DEVELOPMENT POSSIBLE ALONG THE BOUNDARY OVER SOUTHERN ZONES. FRONT PROGGED TO SHIFT SOUTH OF THE AL BORDER BY WEDNESDAY NIGHT WITH SLIGHTLY COOLER AND DRY WEATHER ANTICIPATED THURSDAY AND FRIDAY. STAYED VERY CLOSE TO PREVIOUS FORECAST TEMPS DURING THIS TIMEFRAME...WHICH ARE ALSO VERY CLOSE TO 12Z MEX GUIDANCE. BY NEXT WEEKEND...MODELS BUILD A STRONG RIDGE OVER THE SOUTHERN PLAINS EASTWARD INTO THE TENNESSEE VALLEY...SUGGESTING A SHARP WARMUP FOR SATURDAY AND SUNDAY WITH HIGHS BACK INTO THE MID 90S FOR MUCH OF MIDDLE TENNESSEE. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
601 PM EDT TUE JUL 8 2014 .SYNOPSIS... A SLOW MOVING COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT AND WEDNESDAY...BEFORE CROSSING THROUGH THE AREA WEDNESDAY NIGHT. HIGH PRESSURE WILL FOLLOW THE FRONT FOR THURSDAY INTO SATURDAY. A MUCH STRONGER COLD FRONT WILL BE PASSING THROUGH THE REGION NEXT MONDAY AND TUESDAY. && .NEAR TERM /THROUGH WEDNESDAY/... UPDATED POPS FOR LATEST WSR-88D TRENDS FOR THUNDERSTORMS MOVING ACROSS THE MOUNTAINS AT THIS TIME. SOME OF THE THUNDERSTORMS ARE STRONG TO SEVERE WITH GUSTY WINDS THE MAIN THREAT.MODIFIED TEMPERATURES AND DEW POINTS FOR LATEST OBS AND SHAPED THIS EVENING INTO TONIGHT. AS OF 315 PM EDT TUESDAY... WATER VAPOR LOOP SHOWED THE FIRST OF TWO SHORT WAVES THAT WILL DEEPEN THE NORTHEAST TROF. THE SECOND WAVE CROSSES THE GREAT LAKES THEN INTO THE NORTHEAST WEDNESDAY NIGHT. LAST FEW RUNS OF THE LOCAL WRF AND HRRR WERE VERY CONSISTENT WITH THE TIMING OF A BAND OF THUNDERSTORMS MOVING IN FROM THE WEST...WHAT WAS CURRENTLY DEVELOPING FROM AROUND PITTSBURGH TO NORTHWEST OF CHARLESTON WV. STILL EXPECTING THIS TO REACH SOUTHEAST WEST VIRGINIA BETWEEN 20-22Z/4-6PM. GUSTY SOUTHWEST SURFACE WINDS AND LOW LEVEL MIXING HAS BROUGHT SURFACE DEW POINTS DOWN INTO THE UPPER 50S TO LOWER 60S...SO CAPES HAVE PEAKED AROUND 2000 J/KG. HOWEVER...AS INDICATED WITH A CLASSIC INVERTED V SOUNDING...DCAPE WAS A HIGH AS 1300 J/KG IN THE FAR SOUTHEAST COUNTY WARNING AREA. IF STORMS MANAGE TO GET INTO THIS ENVIRONMENT AND OVERCOME THE DOWNSLOPING EAST OF THE BLUE RIDGE THERE IS A POTENTIAL FOR STRONG TO DAMAGING WINDS. WITH THE REMOVAL OF HEATING...INTENSITY AND COVERAGE OF PRECIPITATION WILL DIMINISH...MAINLY AFTER 02Z/10PM. THE SOUTHERN END OF THE LINE OF STORMS...EXTENDING ACROSS THE TENNESSEE VALLEY MAY CONTINUE OVERNIGHT. HAVE KEPT A HIGHER PROBABILITY OF PRECIPITATION IN THE SOUTHWEST COUNTY WARNING AREA THROUGH WEDNESDAY MORNING. EXPECTING LITTLE PROGRESS IN THE EASTWARD MOVEMENT OF THE SURFACE COLD FRONT TONIGHT AND WEDNESDAY WITH BROAD SOUTHWEST FLOW PARALLEL TO THE BOUNDARY AND LIMITED MOVEMENT OF THE UPPER TROF. BEST PROBABILITY OF PRECIPITATION WEDNESDAY WILL BE IN THE AFTERNOON WITH AREAS OF SURFACE BASED IN STABILITY AND CONVERGENCE...PLUS ALONG ANY OUTFLOW PRODUCED BY THE THUNDERSTORMS THAT DEVELOP THIS AFTERNOON. NARROWING DOWN WHERE THIS WILL BE IS THE BIGGEST CHALLENGE. LOOKING FOR MUGGY CONDITIONS WILL DEW POINTS RISING BACK UP THROUGH THE 60S TONIGHT...ESPECIALLY WHERE IT RAINS. AMOUNT OF CLOUDS WILL DETERMINE HOW HOT TEMPERATURES WILL GET ON WEDNESDAY. WILL BE DEPENDENT ON WHERE IT IS RAINING IN THE MORNING. FOR NOW STAYED CLOSED TO THE MET GUIDANCE FOR MAXIMUM TEMPERATURES. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... AS OF 310 PM EDT TUESDAY... WEAK COOL FRONT EXPECTED TO DRIFT SOUTHEAST THROUGH THE BLACKSBURG FORECAST AREA WEDNESDAY NIGHT. ACTUAL SURFACE REFLECTION WILL LIKELY BE DIFFICULT TO DEFINE CONSIDERING DIFFUSE NATURE OF FRONT...AND CONTAMINATION FROM COOL OUTFLOW BOUNDARIES GENERATED BY CONVECTIVE ACTIVITY PRECEDING IT. HOWEVER...UPPER TROF WILL REMAIN TO THE WEST...AND WITH SUBTLE BACKING OF LOW LEVEL FLOW EXPECTED AHEAD OF UPPER TROF...ALONG WITH GRADUAL COOLING ALOFT...SUPPORT FOR PRE- AND POST-FRONTAL PRECIPITATION MAY PERSIST WELL INTO THE EVENING...AND PERHAPS THOUGH MUCH OF THE NIGHT ACROSS SOUTHERN/SOUTHEASTERN AREAS. NORTHWESTERN AREAS SHOULD REMAIN DRY...OTHER THAN PERHAPS A LINGERING EARLY EVENING SHOWER. ALTHOUGH NORTHWESTERN AREAS EXPECTED TO REMAIN DRY ON THURSDAY...PROXIMITY OF OLD FRONTAL BOUNDARY LYING JUST TO THE SOUTH AND EAST...AND LIMITED ADDITIONAL MOVEMENT EAST OF UPPER TROF WARRANTS CONTINUED AT LEAST LOW THREAT FOR DIURNALLY DRIVEN SHOWERS OR THUNDERSTORMS ACROSS THE SOUTH AND SOUTHEAST PORTION OF THE FORECAST AREA DURING THE AFTERNOON INTO THE EVENING. UPPER TROF FINALLY EXPECTED TO MOVE OVER AND THEN JUST TO THE EAST OF THE FORECAST AREA ON FRIDAY...BUT PLACEMENT SUPPORTS AMPLIFICATION OF SURFACE RIDGE JUST TO OUR NORTHEAST WHICH ALLOWS LOW LEVEL FLOW TO VEER AROUND BY DAYS END INTO THE EAST. COMBINATION OF COOLER AIR ALOFT...PLENTY OF INSOLATION...AND LIGHT UPSLOPING AGAINST THE EASTERN FLANKS OF THE BLUE RIDGE MAY BE SUFFICIENT TO OVERCOME DEVELOPING CAP TO SUPPORT ISOLATED TO WIDELY SCATTERED CONVECTION ALONG AND EAST OF THE BLUE RIDGE BEFORE DIMINISHING WITH LOSS OF DAYTIME HEATING FRIDAY EVENING. POST FRONTAL TEMPERATURES WILL BE SLIGHTLY COOLER THAN THE PAST SEVERAL DAYS...MAINLY 70S TO AROUND 80 ACROSS THE HIGHER ELEVATIONS TO MAINLY 80S PIEDMONT...WITH 50S IN THE MOUNTAIN VALLEYS TO MAINLY 60S ACROSS THE PIEDMONT AT NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 310 PM EDT TUESDAY... DAILY THREAT OF WIDELY SCATTERED TO SCATTERED DIURNALLY DRIVEN SHOWERS/THUNDERSTORMS APPEARS TO BE IN THE OFFING DURING THE LONG TERM PERIOD AS A SERIES OF WEAK SHORT WAVES IN RELATIVELY ZONAL FLOW FORECAST TO MOVE EAST THROUGH THE BLACKSBURG FORECAST AREA. FIRST WAVE EXPECTED ON SATURDAY...WITH SECOND WAVE ON SUNDAY...TO BE FOLLOWED BY MUCH MORE SUBSTANTIAL WAVE IN MONDAY/TUESDAY TIMEFRAME AS EASTERN CANADIAN UPPER LOW AMPLIFIES AND RETROGRESSES SOUTHWESTWARD INTO THE UPPER GREAT LAKES AREA. DEEPENING VERY BROAD UPPER TROF/CLOSED SYSTEM WILL SUPPORT A GOOD PUSH OF UNUSUALLY COOL AIR INTO THE MID APPALACHIAN AND MID ATLANTIC REGION BY THE END OF THE LONG TERM PERIOD...BUT WITH THE COOLEST PORTION OF THE AIRMASS TO ARRIVE JUST OUTSIDE OF THIS FORECAST PERIOD...ON WEDNESDAY. AT LEAST THROUGH MONDAY...EXPECT RELATIVELY SEASONAL TEMPERATURES WITH NO SIGNIFICANT DAY TO DAY CHANGES IN AIRMASS. HIGHS SHOULD RANGE FROM THE MID 70S TO LOWER 80S ACROSS THE HIGHER ELEVATIONS TO UPPER 80S TO LOWER 90S ACROSS THE PIEDMONT. OVERNIGHT LOWS SHOULD BE GENERALLY IN THE 60S...BUT WITH SOME UPPER 50S POSSIBLE ACROSS THE HIGHEST ELEVATIONS AND IN THE DEEPER MOUNTAIN VALLEYS. TEMPERATURES SHOULD BEGIN TRENDING DOWNWARD ABOUT 5F DAILY BEGINNING TUESDAY AS LEADING EDGE OF SUCCESSIVE WAVES OF COOLER AIR BEGIN TO IMPINGE UPON THE AREA. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... AS OF 145 PM EDT TUESDAY... COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF. BAND OF SHOWERS AND THUNDERSTORMS WILL FORM FROM WESTERN PENNSYLVANIA TO EASTERN KENTUCKY AND MOVE EAST DURING THE EVENING. LAST FEW RUNS OF THE HRRR...AS WELL AS THE RUC AND LOCAL WRF HAVE THE STORMS REACHING KBLF AND KBLF FROM 20-21Z/4-5PM. LOWER CONFIDENCE AS TO HOW FAR EAST SHOWERS AND THUNDERSTORMS WILL PROGRESS. HAVE LEFT VCNTY THUNDER IN THE KBCB...KROA AND KLYH TAFS. THE LEAST LIKELY LOCATION TO GET STORMS WILL BE AT KDAN AS LONG AS SCATTERED TO ISOLATED THUNDERSTORMS DO NOT DEVELOP IN THE FOOTHILLS OF THE BLUE RIDE. AS LOWER DEW POINTS MIX DOWN TO THE SURFACE THIS AFTERNOON...THE INSTABILITY WAS BECOMING LESS FAVORABLE FOR THUNDERSTORMS IN THE LEE-TROF. LOSS OF HEATING AND WESTERLY DOWNSLOPE WIND WILL WEAKEN SHOWERS AND THUNDERSTORMS BY 02Z/10PM. MODELS SHOWED LINGERING SHOWERS FROM SOUTHERN WEST VIRGINIA TO EASTERN TENNESSEE OVERNIGHT. DO NOT HAVE ANY IMPACT FROM THIS POTENTIAL RAINFALL IN THE TAFS BUT HAVE ADDED MVFR CEILINGS TO KBLF AFTER MIDNIGHT. ALSO ADDED LIFR FOG AND CEILINGS IN FOR KLWB OVERNIGHT..EXPECTING THERE WILL BE RAIN AT THAT AIRPORT LATE THIS AFTERNOON. EXTENDED AVIATION... BEST CHANCE FOR THUNDERSTORMS ON WEDNESDAY WILL BE IN THE AFTERNOON IN CENTRAL AND EASTERN VIRGINIA AND NORTH CAROLINA WHERE THE INSTABILITY WILL COMBINE WITH OUTFLOW FROM PREVIOUS STORMS. THE COLD FRONT WILL FINALLY PUSH THROUGH THE REGION ON WEDNESDAY NIGHT. THE FRONT WILL LINGER ACROSS SOUTHERN/EASTERN AREAS THROUGH THE END OF THE WEEK WITH IMPULSES RIDING ALONG IT. THIS WILL KEEP UNSETTLED CONDITIONS AT TAF SITES THROUGH THE END OF THE WEEK. EXPECT DIURNAL TRENDS FOR AFTERNOON CONVECTIVE PRECIPITATION WITH ASSOCIATED MVFR OR LOWER CONDITIONS... ESPECIALLY FOR KDAN/KLYH...AND POSSIBLE IFR FOG LATE NIGHTS...MAINLY KBCB AND KLWB. && .CLIMATE... AS OF 315 PM EDT TUESDAY... THIS WAS THE 3RD DRIEST JUNE ON RECORD AT DANVILLE WITH ONLY 1.23 INCHES OF PRECIPITATION. RECORDS GO BACK TO 1948. THE DRIEST JUNE ON RECORD IS 1.06 INCHES IN 2008. && .EQUIPMENT... AS OF 315 PM EDT TUESDAY... COMMUNICATIONS OUTAGE CONTINUES WITH KDAN ASOS NOT TRANSMITTING. THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/KK SHORT TERM...WERT LONG TERM...AMS/WERT AVIATION...AMS/JH CLIMATE...AMS/PC EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
325 PM EDT TUE JUL 8 2014 .SYNOPSIS... A SLOW MOVING COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT AND WEDNESDAY...BEFORE CROSSING THROUGH THE AREA WEDNESDAY NIGHT. HIGH PRESSURE WILL FOLLOW THE FRONT FOR THURSDAY INTO SATURDAY. A MUCH STRONGER COLD FRONT WILL BE PASSING THROUGH THE REGION NEXT MONDAY AND TUESDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 315 PM EDT TUESDAY... WATER VAPOR LOOP SHOWED THE FIRST OF TWO SHORT WAVES THAT WILL DEEPEN THE NORTHEAST TROF. THE SECOND WAVE CROSSES THE GREAT LAKES THEN INTO THE NORTHEAST WEDNESDAY NIGHT. LAST FEW RUNS OF THE LOCAL WRF AND HRRR WERE VERY CONSISTENT WITH THE TIMING OF A BAND OF THUNDERSTORMS MOVING IN FROM THE WEST...WHAT WAS CURRENTLY DEVELOPING FROM AROUND PITTSBURGH TO NORTHWEST OF CHARLESTON WV. STILL EXPECTING THIS TO REACH SOUTHEAST WEST VIRGINIA BETWEEN 20-22Z/4-6PM. GUSTY SOUTHWEST SURFACE WINDS AND LOW LEVEL MIXING HAS BROUGHT SURFACE DEW POINTS DOWN INTO THE UPPER 50S TO LOWER 60S...SO CAPES HAVE PEAKED AROUND 2000 J/KG. HOWEVER...AS INDICATED WITH A CLASSIC INVERTED V SOUNDING...DCAPE WAS A HIGH AS 1300 J/KG IN THE FAR SOUTHEAST COUNTY WARNING AREA. IF STORMS MANAGE TO GET INTO THIS ENVIRONMENT AND OVERCOME THE DOWNSLOPING EAST OF THE BLUE RIDGE THERE IS A POTENTIAL FOR STRONG TO DAMAGING WINDS. WITH THE REMOVAL OF HEATING...INTENSITY AND COVERAGE OF PRECIPITATION WILL DIMINISH...MAINLY AFTER 02Z/10PM. THE SOUTHERN END OF THE LINE OF STORMS...EXTENDING ACROSS THE TENNESSEE VALLEY MAY CONTINUE OVERNIGHT. HAVE KEPT A HIGHER PROBABILITY OF PRECIPITATION IN THE SOUTHWEST COUNTY WARNING AREA THROUGH WEDNESDAY MORNING. EXPECTING LITTLE PROGRESS IN THE EASTWARD MOVEMENT OF THE SURFACE COLD FRONT TONIGHT AND WEDNESDAY WITH BROAD SOUTHWEST FLOW PARALLEL TO THE BOUNDARY AND LIMITED MOVEMENT OF THE UPPER TROF. BEST PROBABILITY OF PRECIPITATION WEDNESDAY WILL BE IN THE AFTERNOON WITH AREAS OF SURFACE BASED IN STABILITY AND CONVERGENCE...PLUS ALONG ANY OUTFLOW PRODUCED BY THE THUNDERSTORMS THAT DEVELOP THIS AFTERNOON. NARROWING DOWN WHERE THIS WILL BE IS THE BIGGEST CHALLENGE. LOOKING FOR MUGGY CONDITIONS WILL DEW POINTS RISING BACK UP THROUGH THE 60S TONIGHT...ESPECIALLY WHERE IT RAINS. AMOUNT OF CLOUDS WILL DETERMINE HOW HOT TEMPERATURES WILL GET ON WEDNESDAY. WILL BE DEPENDENT ON WHERE IT IS RAINING IN THE MORNING. FOR NOW STAYED CLOSED TO THE MET GUIDANCE FOR MAXIMUM TEMPERATURES. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... AS OF 310 PM EDT TUESDAY... WEAK COOL FRONT EXPECTED TO DRIFT SOUTHEAST THROUGH THE BLACKSBURG FORECAST AREA WEDNESDAY NIGHT. ACTUAL SURFACE REFLECTION WILL LIKELY BE DIFFICULT TO DEFINE CONSIDERING DIFFUSE NATURE OF FRONT...AND CONTAMINATION FROM COOL OUTFLOW BOUNDARIES GENERATED BY CONVECTIVE ACTIVITY PRECEDING IT. HOWEVER...UPPER TROF WILL REMAIN TO THE WEST...AND WITH SUBTLE BACKING OF LOW LEVEL FLOW EXPECTED AHEAD OF UPPER TROF...ALONG WITH GRADUAL COOLING ALOFT...SUPPORT FOR PRE- AND POST-FRONTAL PRECIPITATION MAY PERSIST WELL INTO THE EVENING...AND PERHAPS THOUGH MUCH OF THE NIGHT ACROSS SOUTHERN/SOUTHEASTERN AREAS. NORTHWESTERN AREAS SHOULD REMAIN DRY...OTHER THAN PERHAPS A LINGERING EARLY EVENING SHOWER. ALTHOUGH NORTHWESTERN AREAS EXPECTED TO REMAIN DRY ON THURSDAY...PROXIMITY OF OLD FRONTAL BOUNDARY LYING JUST TO THE SOUTH AND EAST...AND LIMITED ADDITIONAL MOVEMENT EAST OF UPPER TROF WARRANTS CONTINUED AT LEAST LOW THREAT FOR DIURNALLY DRIVEN SHOWERS OR THUNDERSTORMS ACROSS THE SOUTH AND SOUTHEAST PORTION OF THE FORECAST AREA DURING THE AFTERNOON INTO THE EVENING. UPPER TROF FINALLY EXPECTED TO MOVE OVER AND THEN JUST TO THE EAST OF THE FORECAST AREA ON FRIDAY...BUT PLACEMENT SUPPORTS AMPLIFICATION OF SURFACE RIDGE JUST TO OUR NORTHEAST WHICH ALLOWS LOW LEVEL FLOW TO VEER AROUND BY DAYS END INTO THE EAST. COMBINATION OF COOLER AIR ALOFT...PLENTY OF INSOLATION...AND LIGHT UPSLOPING AGAINST THE EASTERN FLANKS OF THE BLUE RIDGE MAY BE SUFFICIENT TO OVERCOME DEVELOPING CAP TO SUPPORT ISOLATED TO WIDELY SCATTERED CONVECTION ALONG AND EAST OF THE BLUE RIDGE BEFORE DIMINISHING WITH LOSS OF DAYTIME HEATING FRIDAY EVENING. POST FRONTAL TEMPERATURES WILL BE SLIGHTLY COOLER THAN THE PAST SEVERAL DAYS...MAINLY 70S TO AROUND 80 ACROSS THE HIGHER ELEVATIONS TO MAINLY 80S PIEDMONT...WITH 50S IN THE MOUNTAIN VALLEYS TO MAINLY 60S ACROSS THE PIEDMONT AT NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 310 PM EDT TUESDAY... DAILY THREAT OF WIDELY SCATTERED TO SCATTERED DIURNALLY DRIVEN SHOWERS/THUNDERSTORMS APPEARS TO BE IN THE OFFING DURING THE LONG TERM PERIOD AS A SERIES OF WEAK SHORT WAVES IN RELATIVELY ZONAL FLOW FORECAST TO MOVE EAST THROUGH THE BLACKSBURG FORECAST AREA. FIRST WAVE EXPECTED ON SATURDAY...WITH SECOND WAVE ON SUNDAY...TO BE FOLLOWED BY MUCH MORE SUBSTANTIAL WAVE IN MONDAY/TUESDAY TIMEFRAME AS EASTERN CANADIAN UPPER LOW AMPLIFIES AND RETROGRESSES SOUTHWESTWARD INTO THE UPPER GREAT LAKES AREA. DEEPENING VERY BROAD UPPER TROF/CLOSED SYSTEM WILL SUPPORT A GOOD PUSH OF UNUSUALLY COOL AIR INTO THE MID APPALACHIAN AND MID ATLANTIC REGION BY THE END OF THE LONG TERM PERIOD...BUT WITH THE COOLEST PORTION OF THE AIRMASS TO ARRIVE JUST OUTSIDE OF THIS FORECAST PERIOD...ON WEDNESDAY. AT LEAST THROUGH MONDAY...EXPECT RELATIVELY SEASONAL TEMPERATURES WITH NO SIGNIFICANT DAY TO DAY CHANGES IN AIRMASS. HIGHS SHOULD RANGE FROM THE MID 70S TO LOWER 80S ACROSS THE HIGHER ELEVATIONS TO UPPER 80S TO LOWER 90S ACROSS THE PIEDMONT. OVERNIGHT LOWS SHOULD BE GENERALLY IN THE 60S...BUT WITH SOME UPPER 50S POSSIBLE ACROSS THE HIGHEST ELEVATIONS AND IN THE DEEPER MOUNTAIN VALLEYS. TEMPERATURES SHOULD BEGIN TRENDING DOWNWARD ABOUT 5F DAILY BEGINNING TUESDAY AS LEADING EDGE OF SUCCESSIVE WAVES OF COOLER AIR BEGIN TO IMPINGE UPON THE AREA. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... AS OF 145 PM EDT TUESDAY... COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF. BAND OF SHOWERS AND THUNDERSTORMS WILL FORM FROM WESTERN PENNSYLVANIA TO EASTERN KENTUCKY AND MOVE EAST DURING THE EVENING. LAST FEW RUNS OF THE HRRR...AS WELL AS THE RUC AND LOCAL WRF HAVE THE STORMS REACHING KBLF AND KBLF FROM 20-21Z/4-5PM. LOWER CONFIDENCE AS TO HOW FAR EAST SHOWERS AND THUNDERSTORMS WILL PROGRESS. HAVE LEFT VCNTY THUNDER IN THE KBCB...KROA AND KLYH TAFS. THE LEAST LIKELY LOCATION TO GET STORMS WILL BE AT KDAN AS LONG AS SCATTERED TO ISOLATED THUNDERSTORMS DO NOT DEVELOP IN THE FOOTHILLS OF THE BLUE RIDE. AS LOWER DEW POINTS MIX DOWN TO THE SURFACE THIS AFTERNOON...THE INSTABILITY WAS BECOMING LESS FAVORABLE FOR THUNDERSTORMS IN THE LEE-TROF. LOSS OF HEATING AND WESTERLY DOWNSLOPE WIND WILL WEAKEN SHOWERS AND THUNDERSTORMS BY 02Z/10PM. MODELS SHOWED LINGERING SHOWERS FROM SOUTHERN WEST VIRGINIA TO EASTERN TENNESSEE OVERNIGHT. DO NOT HAVE ANY IMPACT FROM THIS POTENTIAL RAINFALL IN THE TAFS BUT HAVE ADDED MVFR CEILINGS TO KBLF AFTER MIDNIGHT. ALSO ADDED LIFR FOG AND CEILINGS IN FOR KLWB OVERNIGHT..EXPECTING THERE WILL BE RAIN AT THAT AIRPORT LATE THIS AFTERNOON. EXTENDED AVIATION... BEST CHANCE FOR THUNDERSTORMS ON WEDNESDAY WILL BE IN THE AFTERNOON IN CENTRAL AND EASTERN VIRGINIA AND NORTH CAROLINA WHERE THE INSTABILITY WILL COMBINE WITH OUTFLOW FROM PREVIOUS STORMS. THE COLD FRONT WILL FINALLY PUSH THROUGH THE REGION ON WEDNESDAY NIGHT. THE FRONT WILL LINGER ACROSS SOUTHERN/EASTERN AREAS THROUGH THE END OF THE WEEK WITH IMPULSES RIDING ALONG IT. THIS WILL KEEP UNSETTLED CONDITIONS AT TAF SITES THROUGH THE END OF THE WEEK. EXPECT DIURNAL TRENDS FOR AFTERNOON CONVECTIVE PRECIPITATION WITH ASSOCIATED MVFR OR LOWER CONDITIONS... ESPECIALLY FOR KDAN/KLYH...AND POSSIBLE IFR FOG LATE NIGHTS...MAINLY KBCB AND KLWB. && .CLIMATE... AS OF 315 PM EDT TUESDAY... THIS WAS THE 3RD DRIEST JUNE ON RECORD AT DANVILLE WITH ONLY 1.23 INCHES OF PRECIPITATION. RECORDS GO BACK TO 1948. THE DRIEST JUNE ON RECORD IS 1.06 INCHES IN 2008. && .EQUIPMENT... AS OF 315 PM EDT TUESDAY... COMMUNICATIONS OUTAGE CONTINUES WITH KDAN ASOS NOT TRANSMITTING. THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...WERT LONG TERM...AMS/WERT AVIATION...AMS/JH CLIMATE...AMS/PC EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
146 PM EDT TUE JUL 8 2014 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY BEFORE SPILLING SLOWLY SOUTHEAST INTO THE AREA ON WEDNESDAY. THIS COMBINED WITH DAYTIME HEATING AND INCREASING MOISTURE...WILL BRING AN INCREASING THREAT FOR SHOWERS AND THUNDERSTORMS...FIRST IN THE FAR WEST LATER TODAY...AND THEN FOR MUCH OF THE AREA BY WEDNESDAY. THE FRONT WILL STRUGGLE TO CLEAR THE PIEDMONT AREAS ON THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1020 AM EDT TUESDAY... HEAT AND HUMIDITY THIS AFTERNOON AS LOW LEVEL SW FLOW ENHANCES AHEAD OF THE APPROACHING UPSTREAM COLD FRONT THIS AFTERNOON. THIS COMBINED WITH DECENT HEATING ESPCLY EARLY ON AND 85H TEMPS AROUND +21C OUT EAST SHOULD AGAIN PUSH HIGHS INTO THE LOW/MID 90S EAST...AND 80S TO PERHAPS CLOSE TO 90 IN SPOTS NEAR THE BLUE RIDGE. HOWEVER STILL WELL BELOW ANY ADVISORY HEADLINES WITH DEWPOINTS AGAIN MIXING LOWER UNDER THE GUSTY SW BREEZE LATER ON. OTRW MAIN CONCERN REMAINS WITH CONVECTIVE COVERAGE ESPCLY VERY LATE THIS AFTERNOON OVER THE FAR WEST AS MODELS SUGGEST AT LEAST A BROKEN LINE OF STORMS WELL IN ADVANCE OF THE BOUNDARY DROPPING SE INTO THE AREA. THIS LOOKS TO AFFECT MAINLY THE SE WVA COUNTIES DOWN TO JUST WEST OF I-77 AFTER 20-22Z/4-6PM OR SO...WITH QUESTIONS TO JUST HOW FAR EAST OR SE THESE STORMS MAY GO GIVEN BEST SUPPORT TO THE NORTH WITH THE UPPER TROF...AND WINDS BACKING TO THE WEST. IF STORMS REDEVELOP ENOUGH TO HAVE AN ORGANIZED COOL POOL...THERE IS JUST ENOUGH INSTABILITY TO BRING SOME OF THIS COVERAGE EAST TO THE BLUE RIDGE AND PERHAPS EAST OF THE MOUNTAINS IN A WEAKENED STATE MAINLY AFTER SUNSET. THIS SUPPORTED MORESO BY THE LATEST NAM/CMC AND SPC WRF AND LESS BY THE GFS WITH THE ECMWF IN BETWEEN. INCREASING UNIDIRECTIONAL FLOW ALOFT AND HIGH FORECAST DCAPES WOULD SUPPORT MORE OF A WIND THREAT AND SEEN VIA THE CURRENT SWODY1. THUS BUMPED UP LIKELY POPS A BIT MORE WESTERN THIRD AND ADDED GUSTY WIND MENTION...WITH A SHARP CUTOFF TO SLIGHT POPS OR LESS OUT EAST THIS AFTERNOON. ANYTHING AHEAD OF THIS LINE WOULD FEATURE MOSTLY ISOLATED THUNDERSTORMS. FRONT WILL STILL BE WEST OF THE MOUNTAINS OVERNIGHT AS A WEAK WAVE HANGS IT UP AND HELPS FOCUS BEST CONVERGENCE ACROSS THE SW CWA UNDER DEEPENING WESTERLY FLOW. THIS SHOULD PIN THE NEXT ROUND OF HIGHER POPS ACROSS THE MTN EMPIRE AREA INTO NW NC OVERNIGHT WITH AGAIN A QUICK DROPOFF IN COVERAGE HEADING EAST PER DOWNSLOPE LIMITING SHRA EAST OF THE BLUE RIDGE AFTER MIDNIGHT. OTRW MOSTLY CLOUDY WEST TO PC ELSW BUT MUGGY WITH LOWS MOSTLY MID 60S VALLEYS TO LOW/MID 70S EAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 310 AM EDT TUESDAY... A BROAD UPPER LEVEL TROUGH WILL ENCOMPASS THE NORTHEAST QUARTER OF THE UNITED STATES...FROM THE NORTH AND CENTRAL PLAINS TO THE CAROLINAS AND MID ATLANTIC REGION...WEDNESDAY AND THURSDAY. A SURFACE FRONT WILL SLIDE ACROSS THE FORECAST AREA WEDNESDAY...STALLING ACROSS THE CAROLINAS WEDNESDAY NIGHT. THIS FRONT WILL BRING A CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE AREA WEDNESDAY. 00Z MODEL SOLUTIONS FOR WEDNESDAY ARE QUITE DIFFERENT FROM 24 HOURS AGO. LATEST SOLUTIONS LIMITING STRONG STORMS WITH MORE MORNING RAIN AND CLOUDS OVER THE AREA. BULK OF THE STRONGER DYNAMICS AND STORMS APPEARS TO BE MOVING SOUTH INTO THE TENNESSEE VALLEY. THE FRONT BUCKLES TO THE NORTHWEST ON THURSDAY AS A WEAK REFLECTION TRACKS ALONG THE STALLED BOUNDARY ACROSS THE CAROLINAS. IF THIS BOUNDARY DOES BUCKLE...AREAS EAST OF THE BLUE RIDGE...PARTICULARLY SOUTHSIDE...WILL SEE ANOTHER ROUND OF PASSING SHOWERS AND THUNDERSTORMS THURSDAY AFTERNOON AND NIGHT. MORNING CLOUDS AND RAIN SHOULD KEEP MOUNTAIN TEMPERATURES NEAR NORMAL...WHILE THE PIEDMONT SEES WARMER THAN NORMAL TEMPERATURES WEDNESDAY. WITH MOST AREAS RESIDING BEHIND THE FRONT ON THURSDAY...TEMPERATURES WILL RUN COOLER THAN NORMAL. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER PATTERN IS AGAIN BECOMING ZONAL THURSDAY NIGHT AND FRIDAY BUT MODELS WERE BRINGING A SHORT WAVE THROUGH THE BASE OF THE EASTERN TROF AND ACROSS THE MID ATLANTIC REGION THURSDAY NIGHT. THE 500 MB TROF DEEPENS AGAIN ON SUNDAY AND MONDAY. SURFACE FRONT IS WELL TO THE SOUTHEAST OF THE FORECAST AREA THURSDAY NIGHT AND FRIDAY BUT ANY WAVE ALONG THE FRONT MAY BRING DEEPER MOISTURE AND A HIGHER PROBABILITY OF PRECIPITATION BACK TOWARD THE SOUTHERN COUNTY WARNING AREA. FORECAST AREA WILL RETURN TO WARM...HUMID...UNSTABLE AIR...AND THE ASSOCIATED CHANCE OF THUNDERSTORMS...SUNDAY AND MONDAY AHEAD OF THE NEXT COLD FRONT. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 145 PM EDT TUESDAY... COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF. BAND OF SHOWERS AND THUNDERSTORMS WILL FORM FROM WESTERN PENNSYLVANIA TO EASTERN KENTUCKY AND MOVE EAST DURING THE EVENING. LAST FEW RUNS OF THE HRRR...AS WELL AS THE RUC AND LOCAL WRF HAVE THE STORMS REACHING KBLF AND KBLF FROM 20-21Z/4-5PM. LOWER CONFIDENCE AS TO HOW FAR EAST SHOWERS AND THUNDERSTORMS WILL PROGRESS. HAVE LEFT VCNTY THUNDER IN THE KBCB...KROA AND KLYH TAFS. THE LEAST LIKELY LOCATION TO GET STORMS WILL BE AT KDAN AS LONG AS SCATTERED TO ISOLATED THUNDERSTORMS DO NOT DEVELOP IN THE FOOTHILLS OF THE BLUE RIDE. AS LOWER DEW POINTS MIX DOWN TO THE SURFACE THIS AFTERNOON...THE INSTABILITY WAS BECOMING LESS FAVORABLE FOR THUNDERSTORMS IN THE LEE-TROF. LOSS OF HEATING AND WESTERLY DOWNSLOPE WIND WILL WEAKEN SHOWERS AND THUNDERSTORMS BY 02Z/10PM. MODELS SHOWED LINGERING SHOWERS FROM SOUTHERN WEST VIRGINIA TO EASTERN TENNESSEE OVERNIGHT. DO NOT HAVE ANY IMPACT FROM THIS POTENTIAL RAINFALL IN THE TAFS BUT HAVE ADDED MVFR CEILINGS TO KBLF AFTER MIDNIGHT. ALSO ADDED LIFR FOG AND CEILINGS IN FOR KLWB OVERNIGHT..EXPECTING THERE WILL BE RAIN AT THAT AIRPORT LATE THIS AFTERNOON. EXTENDED AVIATION... BEST CHANCE FOR THUNDERSTORMS ON WEDNESDAY WILL BE IN THE AFTERNOON IN CENTRAL AND EASTERN VIRGINIA AND NORTH CAROLINA WHERE THE INSTABILITY WILL COMBINE WITH OUTFLOW FROM PREVIOUS STORMS. THE COLD FRONT WILL FINALLY PUSH THROUGH THE REGION ON WEDNESDAY NIGHT. THE FRONT WILL LINGER ACROSS SOUTHERN/EASTERN AREAS THROUGH THE END OF THE WEEK WITH IMPULSES RIDING ALONG IT. THIS WILL KEEP UNSETTLED CONDITIONS AT TAF SITES THROUGH THE END OF THE WEEK. EXPECT DIURNAL TRENDS FOR AFTERNOON CONVECTIVE PRECIPITATION WITH ASSOCIATED MVFR OR LOWER CONDITIONS... ESPECIALLY FOR KDAN/KLYH...AND POSSIBLE IFR FOG LATE NIGHTS...MAINLY KBCB AND KLWB. && .EQUIPMENT... COMMS ISSUES WITH KDAN ASOS NOT TRANSMITTING. THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...JH/SK NEAR TERM...AMS/JH SHORT TERM...RCS LONG TERM...AMS AVIATION...AMS/JH EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1130 PM CDT MON JUL 7 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 203 PM CDT MON JUL 7 2014 MAIN SHORT TERM CONCERN IS ON SEVERE POTENTIAL THROUGH THE EVENING. CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO BRITISH COLUMBIA WHILE TROUGHING PRESIDED OVER EASTERN CANADA. THE MAIN FEATURE OF INTEREST WAS A FAIRLY POTENT SHORTWAVE AT THE SOUTHWEST END OF THIS TROUGHING OVER NORTH DAKOTA. A CLUSTER OF SHOWERS AND THUNDERSTORMS CONTINUES TO ROLL AHEAD OF THE SHORTWAVE IN THE DPVA REGION...BEING ENHANCED NOW BY DAYTIME HEATING. THERE IS ALSO AN UPPER JET STREAK GOING FROM MONTANA INTO SOUTH DAKOTA...PROVIDING UPPER DIVERGENCE FOR THOSE STORMS. CLOSER TO THE FORECAST AREA...SHOWERS AND THUNDERSTORMS HAVE BEEN DEVELOPING FROM CENTRAL MN INTO THE NORTH HALF OF WI. A WEAK SHORTWAVE TRAVERSING THROUGH THE FLOW...COMBINED WITH WEAK MID LEVEL FRONTOGENESIS AND 1000 J/KG OF UNCAPPED MLCAPE PER RAP ARE CONTRIBUTING TO THEIR DEVELOPMENT. HAVE HAD A FEW ISOLATED SEVERE SUPERCELLS DEVELOP TOO. ANOTHER PLUME OF LITTLE HIGHER INSTABILITY...1000-2000 J/KG PER RAP...WAS EVIDENT ACROSS NORTH CENTRAL IOWA STREAMING NORTHEASTWARD ASSOCIATED WITH CORN EVAPOTRANSPORATION. TEMPERATURES HAVE CLIMBED NICELY DUE TO CLEAR SKIES THIS MORNING AND HAVING 850MB TEMPS OF 15-18C. MAIN SURFACE COLD FRONT EXTENDED FROM NORTHERN MN INTO EASTERN SOUTH DAKOTA. THE POTENT SHORTWAVE OVER NORTH DAKOTA IS FORECAST TO MOVE SOUTHEAST ACROSS THE FORECAST AREA OVERNIGHT TONIGHT. IN RESPONSE...THERE ARE SOME VERY IMPRESSIVE 500MB HEIGHT FALLS FOR EARLY JULY...ON THE ORDER OF 60-80 METERS IN 12 HOURS. NEEDLESS TO SAY...THERE IS PLENTY OF DYNAMIC FORCING COMING ACROSS THIS EVENING. ADDITIONALLY...THAT UPPER JET STREAK GOING ACROSS SOUTH DAKOTA NOW SHOULD SLIDE JUST TO OUR SOUTH IN IOWA...PROVIDING UPPER DIVERGENCE SUPPORT. THROW IN LINGERING AFTERNOON INSTABILITY AND THIS PROVIDES A GREAT RECIPE FOR CONVECTION THIS EVENING. MAJORITY OF DETERMINISTIC AND HIGH RESOLUTION MODELS AGREE AS WELL...WITH A MAX PRECIPITATION COVERAGE TIME LIKELY CENTERED NEAR 03Z. THE GREATEST SEVERE POTENTIAL WILL EXIST MOSTLY BETWEEN 23-03Z... WHEN THE DYNAMICS ARE JUXTAPOSED ON TOP OF THE THERMODYNAMICS...AND STORMS CAN MAINTAIN SOME ISOLATION OF INFLOW. STILL COULD HAVE SOME ISOLATED SEVERE BEFORE THEN LIKE WE ARE OBSERVING NOW. 0-3KM AND 0-6 KM SHEAR STILL REMAIN FAVORABLE FOR ORGANIZED SEVERE CONVECTION...30- 35 KT AND 40-55 KT RESPECTIVELY. HODOGRAPHS ARE MAINLY STRAIGHT LINE...SUGGESTING SPLITTING SUPERCELLS...WHILE THE SHEAR ALSO FAVORS BOWING LINE SEGMENTS. GIVEN A MAINLY UNIDIRECTIONAL FLOW FROM SURFACE TO THE MID LEVELS...BELIEVE DAMAGING WINDS AND LARGE HAIL ARE THE MAIN CONCERNS. STRONG SUBSIDENCE IN THE WAKE OF THE POTENT SHORTWAVE OVERNIGHT SHOULD HELP TO CLEAR THE PRECIPITATION WEST TO EAST. THE FORECAST AREA COULD BE COMPLETELY DRY BY 09Z. ATTENTION THEN TURNS TO THE UPPER TROUGH SET UP FROM NORTHERN ONTARIO SOUTHWARD THROUGH THE WESTERN GREAT LAKES REGION ON TUESDAY. THE COLD POOL ASSOCIATED WITH THIS TROUGH...REFLECTED BY 500MB TEMPS OF -13 TO -15C...COULD BE ENOUGH TO INSTIGATE SOME SHOWERS AND THUNDERSTORMS WITH DAYTIME HEATING. HOWEVER...THERE ARE SOME ISSUES THAT WOULD FAVOR A DRIER FORECAST. FIRST...MODELS AGAIN ARE LIKELY OVERDOING SURFACE DEWPOINTS AND INSTABILITY...ESPECIALLY GIVEN A NORTHWEST FLOW WOULD FAVOR A GOOD DRYING/MIXING SCENARIO. SECOND...SHORTWAVES ROTATING THROUGH THE UPPER TROUGH APPEAR TO TRACK NORTH OF THE FORECAST AREA. THUS...HAVE ONLY KEPT PRECIPITATION CHANCES IN THE 20-30 RANGE. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 203 PM CDT MON JUL 7 2014 A NICE DRY PERIOD IS EXPECTED FOR THE FORECAST AREA TUESDAY NIGHT THROUGH THURSDAY...RESULTING FROM THE UPPER TROUGH GRADUALLY SHIFTING EAST...UPPER RIDGING EVENTUALLY BUILDING INTO THE AREA BY 00Z FRIDAY...AND SURFACE RIDGING BUILDING IN. PRECIPITABLE WATER IS ALSO FORECAST BETWEEN 0.5-1 INCH...OR ANYWHERE FROM 50-100 PERCENT OF NORMAL...SUPPORTING A DRY FORECAST AND ALSO ALLOWING FOR LARGER DIURNAL SWINGS. NIGHTTIME LOWS COULD GET RELATIVELY CHILLY WEDNESDAY NIGHT IN CENTRAL WISCONSIN WITH THE SURFACE RIDGE OVERHEAD. THEREFORE IT ALSO SEEMS TO BE THE BEST NIGHT TO HAVE TRIBUTARY VALLEY FOG. THE WEATHER THEN STARTS TO POSSIBLY TURN MORE ACTIVE AGAIN LATE THURSDAY NIGHT AND RIGHT INTO THE WEEKEND. THIS IS A RESULT OF VERY GOOD MOISTURE RETURN...CHARACTERIZED BY PRECIPITABLE WATER UPWARDS OF 1.5-1.8 INCHES...FLOWING BACK INTO THE AREA ON THE BACK SIDE OF THE SURFACE HIGH. MEANWHILE...IN THE SYNOPTIC SCALE...AN UPPER TROUGH IS PROGGED TO DROP SOUTH OUT OF CANADA INTO OUR REGION. SOME OF THE DETAILS ARE HARD TO PIN DOWN RIGHT NOW...BUT CERTAINLY FROM LATE THURSDAY NIGHT THROUGH SUNDAY THERE COULD BE OFF AND ON SHOWERS AND THUNDERSTORMS AROUND. THIS CREATES SOME UNCERTAINTY ON TEMPERATURES...ESPECIALLY GIVEN THAT AT LEAST FRIDAY 850MB TEMPS ARE 15-18C AND COULD BE SIMILAR ON SATURDAY. NOTE THAT A GENERAL COOLING IS EXPECTED HEADING INTO EARLY NEXT WEEK...ESPECIALLY IF THE 07.00Z/12Z ECMWF RUNS ARE RIGHT WHERE THEY SHOW 850MB TEMPS FALLING TO 6C ON MONDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1130 PM CDT MON JUL 7 2014 STORMS HAVE EXITED...LEAVING SKC/SCT SKIES. SEE SOME THREAT FOR FOG IF WINDS WOULD DECOUPLE AT KLSE. SFC PRESSURE GRADIENT WILL STAY TIGHT THROUGH THE NIGHT THOUGH...AND NOT MUCH INDICATION OF DECOUPLING VIA THE BUFKIT SOUNDINGS. SO WILL MONITOR...BUT DON/T THINK VALLEY FOG IS FAVORABLE AT THE MOMENT. FOR TUE...WI WILL BE UNDER CYCLONIC FLOW AS THE UPPER LEVEL LOW EXITS EAST. SHOULD SEE BKN CIGS DEVELOP OVER CENTRAL/EASTERN WI...WITH SOME AFTERNOON -SHRA POSSIBLE. COULD SEE SOME BKN VFR AT KLSE...BUT BELIEVE THE BULK OF THE -SRHA THREAT WILL STAY EAST. && .HYDROLOGY... ISSUED AT 203 PM CDT MON JUL 7 2014 THE MISSISSIPPI RIVER CONTINUES TO FALL. IN FACT...WE ARE EXPECTING ALL THE RIVER FORECAST POINTS WITHIN THE ARX FORECAST AREA TO FALL BELOW FLOOD STAGE BY THURSDAY FROM NORTH TO SOUTH. FLOOD WARNINGS HAVE BEEN CANCELLED AT WINONA AND LA CROSSE AND WILL SOON BE AT WABASHA. PERIODIC RAIN IS FORECAST OVER THE NEXT FEW DAYS...BUT IT APPEARS THIS RAINFALL WILL NOT BE ENOUGH TO HAVE A SIGNIFICANT IMPACT ON THE MISSISSIPPI...OR ITS TRIBUTARIES FOR THAT MATTER. FOR THE CURRENT AND FORECAST RIVER LEVELS...SEE OUR INTERNET PAGE AT WWW.WEATHER.GOV/LACROSSE. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM....AJ AVIATION.....RIECK HYDROLOGY....AJ
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
244 AM MDT THU JUL 10 2014 .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 223 AM MDT THU JUL 10 2014 THE UPPER LEVEL RIDGE OVER THE SRN ROCKIES WILL EXPAND NORTHWARD THRU THIS AFTN INTO NRN CO WITH THE MID FLOW BECOMING MORE WSW. PRECIPITABLE WATER VALUES EAST OF THE MTNS HAVE DECREASED AROUND 25% FROM YESTERDAY WHILE OVER WRN CO THEY ARE SLIGHTLY HIGHER. MEANWHILE WITH THE UPPER LEVEL RIDGE BUILDING NORTHWARD MID LVL TEMPS ARE FCST TO RISE A FEW DEGREES AS WELL. IN THE MTNS WILL CONTINUE TO SEE A CHC OF SHOWERS AND TSTMS THIS AFTN. OVER NERN CO AM SOMEWHAT CONCERNED WITH THE MID LVL WARMING THIS AFTN WHICH COULD INHIBIT CONVECTION IN MOST AREAS EXCEPT POSSIBLY NEAR THE WY BORDER. THUS WILL KEEP POPS IN THE 10 TO 20 PERCENT RANGE FOR THIS AFTN INTO THE EVENING HOURS EXCEPT NR THE WY BORDER WHERE THERE WILL BE SLIGHTLY HIGHER POPS. WITH LESS INSTABILITY THIS AFTN AND WK SHEAR PROFILE THREAT OF SVR WX LOOKS LOW. AS FOR HIGHS 850-700 MB TEMPS RISE ANOTHER COUPLE OF DEGREES SO AFTN HIGHS WILL BE MOSTLY IN THE MID TO UPPER 90S ACROSS NERN CO. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 223 AM MDT THU JUL 10 2014 MODELS SHOW THE UPPER RIDGE CENTER JUST SOUTHEAST OF COLORADO FRIDAY THROUGH FRIDAY EVENING...THEN THE CENTER MIGRATES WESTWARD SATURDAY MORNING. IT IS CENTERED OVER THE EASTERN GREAT BASIN BY 12Z SUNDAY MORNING. THE FLOW ALOFT IS WEAK WEST-SOUTHWESTERLY FRIDAY AND FRIDAY NIGHT...THEN ZONAL SATURDAY AND SATURDAY EVENING...THEN WEST-NORTHWESTERLY BY 12Z SUNDAY MORNING. WEAK UPWARD QG VERTICAL VELOCITY IS PROGGED FOR THE CWA FRIDAY THROUGH SATURDAY. THE BOUNDARY LAYER FLOW LOOKS TO BE PREDOMINATELY UPSLOPE FRIDAY...FRIDAY NIGHT AND SATURDAY. THERE ARE A COUPLE OF COLD FRONTS PROGGED INTO THE CWA. THE MORE SIGNIFICANT ONE IS FOR FRIDAY. FOR MOISTURE...THERE IS PLENTY PROGGED FRIDAY THROUGH SATURDAY NIGHT. PRECIPITABLE WATER VALUES ON ALL THE MODELS FOR ALL THE PLAINS AND LOWER FOOTHILLS ARE PROGGED OVER 1.00 INCH FRIDAY THROUGH SATURDAY NIGHT. BOUNDARY LAYER DEW POINTS ARE IN THE 50 TO 65 F RANGE FOR THE PLAINS AND FOOTHILLS ALL FOUR PERIODS. PRETTY DECENT CAPE IS PROGGED OVER THE CWA...ESPECIALLY DURING THE AFTERNOONS AND EVENINGS. SOME AREAS OF THE PLAINS HAVE VALUES OVER 2000 J/KG. THE QPF FIELDS HAVE WIDESPREAD MEASURABLE PRECIPITATION OVER THE CWA LATE DAY FRIDAY AND LATE DAY SATURDAY. THE GFS HAS THE HIGHEST AMOUNTS BUT ALL THE MODELS WEIGHT IN WITH SOMETHING. WILL GO WITH 30-50% POPS FRIDAY LATE AND SATURDAY LATE. WILL EVEN KEEP SOME GOING...ESPECIALLY OVER THE EAST FOR THE 06-12Z PERIODS. FOR TEMPERATURES...FRIDAY`S HIGHS ARE 3-6 C COOLER THAN TODAY`S WITH THE COOLER AIRMASS AND MORE MOISTURE. SATURDAY`S HIGHS ARE 0-1 C COOLER THAN FRIDAY`S. FOR THE LATER DAYS...SUNDAY THROUGH WEDNESDAY...MODELS HAVE THE UPPER RIDGE CENTER STAYING OVER THE GREAT BASIN SUNDAY THROUGH TUESDAY NIGHT...THEN IT MOVES FURTHER WEST THROUGH WEDNESDAY. AN UPPER TROUGH/CLOSED LOW IS PROGGED OVER THE NORTHERN AND NORTHEASTERN UNITED STATES SUNDAY THROUGH TUESDAY...WITH ITS TAIL END GETTING INTO THE CWA PERHAPS. LATER TUESDAY INTO WEDNESDAY...A WEAK UPPER TROUGH IS PROGGED TO MOVE INTO THE CWA. THERE WILL BE COOLER TEMPERATURES AND MOISTURE FOR POPS. && .AVIATION...(FOR THE TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 223 AM MDT THU JUL 10 2014 TSTM CHANCES LOOK RATHER LOW TODAY HOWEVER STILL CAN`T RULE OUT AN ISOLATED HIGH BASED STORM IF OUTFLOW BOUNDARIES FM HIGHER TERRAIN CONVECTION MOVE ACROSS LATE THIS AFTN SO WILL LEAVE VCTS IN TAF. AS FAR AS WINDS WILL TREND TOWARDS THE HRRR AND HAVE AN ESE COMPONENT DEVELOPING BY EARLY AFTN WITH SPEEDS IN THE 10-15 MPH RANGE. MAY SEE A WIND SHIFT TO THE NW AROUND 00Z IF OUTFLOW BOUNDARIES MOVE ACROSS AND THEN MORE SWLY BY 02Z WITH DRAINAGE WINDS OVERNIGHT. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RPK LONG TERM...RJK AVIATION...RPK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1109 PM MDT WED JUL 9 2014 .UPDATE... ISSUED AT 903 PM MDT WED JUL 9 2014 QUICK UPDATE TO ACCOUNT FOR THE LATEST RADAR TRENDS. CURRENTLY A BAND OF STRONG THUNDERSTORMS IS DROPPING SOUTH OUT OF CHEYENNE AND KIT CARSON COUNTIES...AND WILL DROP SOUTH ACROSS OUR FAR EASTERN PLAINS COUNTIES THROUGH 1 AM. STRONG OUTFLOW WINDS TO 50 MPH AND HALF INCH HAIL ARE POSSIBLE AS THESE STORMS DROP SOUTH. LIGHT RAINFALL WITH ISOLATED THUNDERSTORMS ARE ALSO CONTINUING OVER THE MOUNTAIN REGIONS...AND SHOULD CONTINUE TO DISSIPATE THROUGH AROUND 2 AM. MOZLEY && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 319 PM MDT WED JUL 9 2014 ANOTHER ROUND OF TSRA OVER THE AREA TODAY...THOUGH SO FAR STORMS HAVE BEEN WEAKER AND HIGHER BASED THAN YESTERDAY`S ACTIVITY...AS PRECIPITABLE WATER HAS DECREASED SIGNIFICANTLY AND LOW LEVEL MOISTURE HAS MIXED AT SOME LOCATIONS ALONG THE I-25 CORRIDOR. STILL SOME FAIRLY STRONG INSTABILITY LEFT NEAR THE KS BORDER...WHERE DEWPOINTS HAVE STAYED IN THE 50S...LEADING TO CAPES IN THE 1-2K J/KG RANGE. FOR THE REST OF THE AFTERNOON AND EARLY EVENING...EXPECT SCT TSRA TO CONTINUE OVER THE MTS...WITH A FEW STORMS DRIFTING ACROSS THE VALLEYS AND INTERSTATE 25 CORRIDOR. LAST COUPLE RUNS OF THE HRRR SUGGEST STORM INTENSITY WON`T BE PARTICULARLY STRONG...ESPECIALLY AS STORMS MOVE AWAY FROM THE HIGHER TERRAIN. STILL...COULD BE A FEW SMALL POCKETS OF BRIEF HEAVY RAIN...MAINLY NEAR THE NM BORDER WHERE INSTABILITY IS A LITTLE BETTER. OVER THE FAR EASTERN PLAINS...WILL HAVE TO WATCH FOR POTENTIAL STRONG/SEVERE CONVECTION DEVELOPING OVER NERN CO BUILDING SOUTHWARD DURING THE EVENING...AS FAIRLY STRONG SHEAR AND HEALTHY SURFACE S-SE FLOW MAY KEEP STORMS GOING PAST SUNSET. HRRR SUPPORTS THIS IDEA WITH A FEW CELLS MOVING ACROSS KIOWA/PROWERS COUNTIES 03Z-04Z. OVERNIGHT...MOST ACTIVITY WILL DIE DURING THE EVENING...THOUGH WILL KEEP SOME LOW POPS GOING OVER THE SAN JUANS WHERE MODELS SUGGEST DEEPER MOISTURE AND A FEW SHOWERS MAY LINGER PAST MIDNIGHT. ON THURSDAY...LITTLE CHANGE IN THE AIR MASS FROM TODAY...THOUGH WITH SURFACE TROUGH PUSHING SLIGHTLY EAST TOWARD THE KS BORDER SUSPECT A LITTLE BETTER MIXING WILL OCCUR ALONG AND EAST OF THE MOUNTAINS...LEADING TO WEAKER/FEWER STORMS ON THE PLAINS/I-25 CORRIDOR. MOUNTAIN ACTIVITY LOOKS LITTLE CHANGED...WITH DEEPEST MOISTURE ALONG THE CONTINENTAL DIVIDE ONCE AGAIN. MAX TEMPS WILL LIKELY CREEP UP A FEW DEGREES OVER EASTERN SECTIONS WITH BETTER MIXING...WITH READINGS NEAR OR A LITTLE OVER 100F FROM PUEBLO EASTWARD. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 319 PM MDT WED JUL 9 2014 THE WEATHER PATTERN IS EXPECTED TO CHANGE VERY LITTLE AS A RIDGE OF HIGH PRESSURE REMAINS OVER THE AREA THROUGH THE WEEKEND. MONSOON MOISTURE TRAPPED UNDER THE RIDGE WILL PROVIDE THE FUEL FOR A DAILY SHOT OF SHOWERS AND THUNDERSTORMS. CONVECTION WILL BE MAINLY DIURNAL...BUT MAY START A BIT EARLIER OVER THE HIGHER TERRAIN DURING THE LATE MORNING HRS...AS WELL AS LINGER INTO THE OVERNIGHT. CONVECTION IS FORECAST TO BE SCATTERED OVER THE MTS...LIKELY OVER THE PEAKS...AND MORE ISOLATED IN NATURE ACROSS THE PLAINS AND SAN LUIS VALLEY. THURSDAY NIGHT THROUGH SUNDAY...A SHORTWAVE PASSING TO THE NORTH LATE THU WILL PUSH A COLD FRONT DOWN INTO EASTERN CO EARLY FRI...THEN A REINFORCING BLAST OF COOLER MORE MOIST AIR COMES IN ON SAT. THIS MEANS VERY WARM TEMPS FOR THE FORECAST AREA ON FRI...NEAR NORMAL LEVELS ON SAT...THEN COOLER ON SUN. THIS WILL ALSO RESULT IN SLIGHTLY HIGHER PCPN CHANCES FOR THE E PLAINS...ESPECIALLY ALONG THE I25 CORRIDOR...FOR SAT AND SUN. MONDAY THROUGH WEDNESDAY...LONG RANGE MODELS INTRODUCE A LARGE UPPER LEVEL LOW PRESSURE SYSTEM THAT DROPS OUT OF CANADA AND HEADS TOWARDS THE GREAT LAKES REGION ON MON...THEN SWEEPS IT TOWARDS THE NEW ENGLAND STATES BY MIDWEEK. IF THIS OCCURS...IT MIGHT PUSH THE UPPER RIDGE OVER THE ROCKIES MORE TO THE SW. FOR NOW...EXPECTED DAY TO DAY CONVECTION CHANCES DO NOT SEEM TO CHANGE MUCH...SAVE FOR COOLER TEMPS ON WED. MOORE && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1107 PM MDT WED JUL 9 2014 VFR CONDITIONS OVERNIGHT FOR ALL THREE TERMINALS. AFTERNOON AND EVENING THUNDERSTORMS ARE POSSIBLE ACROSS THE MOUNTAINS ON THURSDAY...WHICH WILL LIKELY MOVE OVER THE SAN LUIS VALLEY AND PALMER DIVIDE. HAVE INCLUDED VCTS IN THE KALS AND KCOS TAFS TO HIGHLIGHT THE POTENTIAL. THERE IS MUCH LESS CERTAINTY AT KPUB WITH A LOW PROBABILITY OF A LATE AFTERNOON OR EVENING THUNDERSTORM. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MOZLEY SHORT TERM...PETERSEN LONG TERM...MOORE AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1242 AM EDT THU JUL 10 2014 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA FROM THE NORTHWEST OVERNIGHT BEFORE STALLING NEAR THE DELMARVA ON THURSDAY. HIGH PRESSURE WILL BRIEFLY BUILD ACROSS THE NORTHEAST FRIDAY INTO SATURDAY, BEFORE IT PUSHES OFFSHORE LATER IN THE DAY SATURDAY. THEN A SERIES OF SURFACE TROUGHS WILL AFFECT THE AREA EARLY NEXT WEEK, FOLLOWED BY A SLOW MOVING COLD FRONT TUESDAY INTO WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A FRONTAL BOUNDARY EXTENDED FROM AROUND RARITAN BAY SOUTHWESTWARD ACROSS LOWER BUCKS COUNTY TO LANCASTER COUNTY AROUND MIDNIGHT. THE BOUNDARY SHOULD CONTINUE TO SINK TO THE SOUTH OVERNIGHT. SHOWERS WERE CONTINUING TO DEVELOP ALONG THE REMNANT OUTFLOW BOUNDARIES FROM EARLIER CONVECTION FROM BERKS COUNTY AND THE LEHIGH VALLEY INTO NORTHERN AND CENTRAL NEW JERSEY. THE ACTIVITY WAS EXPERIENCING A WEAKENING TREND AND BASED ON THE HRRR THAT TREND SHOULD CONTINUE WITH MOST OF THE PRECIPITATION DISSIPATING BY ABOUT 300 AM. WE WILL KEEP A SLIGHT CHANCE OF SHOWERS ACROSS MUCH OF THE SOUTHERN PART OF OUR FORECAST AREA OVERNIGHT DUE TO THE FRONTAL BOUNDARY. HOWEVER, THERE SHOULD BE NO OTHER SIGNIFICANT TRIGGERS FOR PRECIPITATION SO WE WILL NOT MENTION THUNDER THERE. MINIMUM TEMPERATURES ARE EXPECTED TO FALL INTO THE UPPER 50S AND LOWER 60S IN THE ELEVATED TERRAIN UP NORTH IN THE WAKE OF THE FRONTAL PASSAGE. MEANWHILE, LOW TEMPERATURES AHEAD OF THE FRONT SHOULD DROP ONLY INTO THE UPPER 60S AND LOWER 70S. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 AM FRIDAY/... AN AMPLIFIED RIDGE OVER THE ATLANTIC OCEAN WILL BE ASSOCIATED WITH AN OMEGA BLOCK THAT DEVELOPS OVER THE GREENLAND. UPSTREAM RAMIFICATIONS OF THIS BLOCKING PATTERN WILL ALLOW THE UPPER LOW TO REMAIN CUTOFF OVER QUEBEC AND ITS ASSOCIATED LONG WAVE TROUGH OVER THE GREAT LAKES AND MIDWEST. OPERATIONAL MODEL GUIDANCE IN FAIRLY GOOD AGREEMENT WITH THE POSITION OF THE COLD FRONT IN SRN NJ/DELMARVA AT 12Z THURSDAY. THE FRONT WILL BECOME ORIENTED PARALLEL TO THE S-SWLY STEERING FLOW IN BETWEEN THE UPSTREAM TROUGH AND DOWNSTREAM RIDGE, CAUSING THE FRONTAL BOUNDARY TO STALL OVER THE SRN THIRD OF THE CWA ON THURSDAY. THE EXPECTED POSITION OF THE STATIONARY FRONT, POSITION OF THE UPPER-LVL JET STREAK, AND TRACK OF A MID-LVL SHORTWAVE TROUGH ALL CONTRIBUTE TO LARGE-SCALE LIFT FOR SRN NJ, DE, AND THE ERN SHORE OF MD. POPS WERE INCREASED IN THESE SRN ZONES BUT DID NOT QUITE HAVE THE FCST CONFIDENCE TO GO WITH LIKELY POPS DUE TO UNCERTAINTIES IN TIMING OF PRECIP. CLOUDS EXPECTED TO LIMIT CONVECTIVE POTENTIAL AND THUS THE SETUP FOR SEVERE TSTMS NOT NEARLY AS FAVORABLE AS YESTERDAY AND TODAY. CLOUD COVER AND SHOWER CHANCES DECREASE FARTHER NORTH. KEPT FCST DRY NORTH OF INTERSTATES 195 AND 76. MAX TEMP FCST WEIGHTED MORE WITH THE MET GUIDANCE. LIKED THE GRIDDED OUTPUT WITH THE WARMEST TEMPS IN THE PHILA METRO AND CENTRAL NJ, JUST NORTH, WHICH MAY BE JUST NORTH OF THE THICKER CLOUD CLOVER. && .LONG TERM /FRIDAY THROUGH THURSDAY/... AT THE BEGINNING OF THE LONG TERM PERIOD, THE FRONTAL BOUNDARY WILL REMAIN STALLED OUT OFFSHORE OF THE EAST COAST, WHILE PW VALUES LOWER SLIGHTLY ACROSS THE AREA INTO FRIDAY. HOWEVER, THERE COULD REMAIN JUST ENOUGH MOISTURE TO INTERACT WITH ANY SHORT WAVE/VORTICITY IMPULSES THAT SLIDE ACROSS THE AREA WITHIN THE BROAD TROUGH ALOFT THAT WILL REMAIN ACROSS THE EAST COAST. THE GREATEST LIKELIHOOD IS ACROSS OUR FAR SOUTHERN NEW JERSEY AND SOUTHERN DELMARVA ZONES, WHICH WILL BE CLOSER TO ANY INFLUENCE OF THE FRONT TO OUR SOUTH AND WHERE ANY MOISTURE REMAINS POOLED. HIGH PRESSURE WILL CONTINUE TO SLIDE ACROSS THE NORTHEAST FRIDAY INTO FRIDAY NIGHT WHICH SHOULD HELP REINFORCE THE DRYING POTENTIAL. THE HIGH BUILDS OFF THE NORTHEAST COAST SATURDAY, WHICH WILL ALLOW A RETURN FLOW TO DEVELOP ACROSS THE AREA. WITH THIS RETURN FLOW, MOISTURE RETURNS, AND WITH A VORTICITY IMPULSE APPROACHING THE AREA SATURDAY, A FEW SCATTERED SHOWERS/THUNDERSTORMS COULD DEVELOP. THESE WILL LIKELY BE MAINLY AFTERNOON/DIURNALLY DRIVEN AND DIMINISH AFTER SUNSET. AS WE MOVE INTO SUNDAY AND EARLY NEXT WEEK, WE ALMOST COPY AND PAST THE FORECAST FROM THE LAST SEVERAL DAYS, AND PASTE IT INTO THE FORECAST SUNDAY THROUGH WEDNESDAY PERIOD NEXT WEEK. AN AREA OF LOW PRESSURE IS EXPECTED TO MOVE INTO SOUTHEASTERN CANADA, WHILE A SERIES OF FRONTAL BOUNDARY CIRCLE AROUND THE LOW ACROSS THE GREAT LAKES AND NORTHEAST. AHEAD OF THESE BOUNDARIES, A PRE-FRONTAL/LEE- SIDE TROUGH IS POSSIBLE EACH DAY. SEVERAL SHORT WAVE/VORTICITY IMPULSES ARE EXPECTED TO MOVE ACROSS OUR AREA EACH DAY, WHICH WILL MAKE SHOWERS AND THUNDERSTORMS POSSIBLE EACH DAY UNTIL THE MAIN COLD FRONT MOVES ACROSS THE AREA. THIS IS NOT EXPECTED UNTIL AT LEAST TUESDAY NIGHT INTO WEDNESDAY. SO WE WILL HAVE AT LEAST A CHANCE OF SHOWERS/THUNDERSTORMS EACH DAY FROM SUNDAY THROUGH TUESDAY. EVEN THOUGH THERE IS A CHANCE EACH DAY, IT IS NOT EXPECTED TO BE A COMPLETE WASHOUT EVERYWHERE EACH DAY. STILL, INSTABILITY WILL BE INCREASING, AND PW VALUES WILL AS WELL. SO WE IT REMAINS POSSIBLE FOR PERIOD OF HEAVY RAINFALL AND STRONG STORMS AS WELL. ANY SEVERE POTENTIAL WILL DEPEND ON EACH DAY`S INSTABILITY AND WIND/SHEAR PROFILES WHICH WILL BECOME MORE EVIDENT IN THE DAYS TO COME. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. MAINLY VFR TONIGHT. THE EXCEPTION WILL BE IN LIGHT FOG WITH SOME MVFR CONDITIONS. THE COLD FRONT WILL PROGRESS SWD THRU THE TERMINALS TNGT AND WILL BE ASSOCIATED WITH A WIND SHIFT FROM S TO NW AND EVENTUALLY N-NE BY THU. ADDITIONAL SHRA EXPECTED IN VC OF ILG/MIV/ACY ON THU. TSRA CHANCES WILL BE LOW. OUTLOOK... THURSDAY NIGHT-FRIDAY...MOSTLY VFR. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS, MAINLY ACROSS OUR SOUTHERN TAF SITES. FRIDAY NIGHT-SATURDAY NIGHT...MVFR CIGS POSSIBLE WITH EASTERLY FLOW. SUNDAY-MONDAY...SHOWERS AND THUNDERSTORMS POSSIBLE, WHICH COULD LOWER CIGS/VSBYS. && .MARINE... EXPECTING WIND SPEEDS TO DECREASE OVERNIGHT WITH 3 TO 4 FOOT SEAS ON THE OCEAN. WINDS SHOULD BE LIGHT ON THURSDAY WITH THE FRONTAL BOUNDARY STALLING OVER THE WATERS. POTENTIAL FOR A FEW TSTMS ON THURSDAY NEAR THE DELAWARE WATERS. OUTLOOK... THURSDAY NIGHT-FRIDAY...SUB-ADVISORY CONDITIONS EXPECTED. CHANCE OF SHOWERS/THUNDERSTORMS, MAINLY SOUTHERN WATERS. HIGHER WINDS/SEAS NEAR THUNDERSTORMS. FRIDAY NIGHT-SATURDAY NIGHT...SUB-ADVISORY CONDITIONS EXPECTED. SUNDAY-MONDAY...SUB-ADVISORY CONDITIONS EXPECTED, BUT WINDS WILL BE INCREASING IN THE SOUTHWESTERLY FLOW AHEAD OF AN APPROACHING FRONTAL BOUNDARY. CHANCE OF SHOWERS/THUNDERSTORMS. HIGHER WINDS/SEAS NEAR THUNDERSTORMS. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...ROBERTSON NEAR TERM...IOVINO SHORT TERM...KLEIN LONG TERM...ROBERTSON AVIATION...KLEIN/ROBERTSON MARINE...KLEIN/KRUZDLO/ROBERTSON
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
134 AM EDT THU JUL 10 2014 .PREV DISCUSSION... /ISSUED 755 PM EDT WED JUL 9 2014/ UPDATE... SCATTERED THUNDERSTORMS WILL OCCUR MAINLY OVER CENTRAL GA ALONG AND SOUTH OF A WEAK FRONTAL BOUNDARY FROM FRANKLIN THROUGH CONYERS TO ATHENS THIS EVENING. AN UPPER LEVEL DISTURBANCE CONTINUES TO TRIGGER ADDITIONAL SCATTERED THUNDERSTORMS OVER EXTREME NORTH GA FROM TRENTON TO DALTON. THE STORMS WILL GENERALLY MOVE EAST AT 15 KTS BEFORE DISSIPATING BY MIDNIGHT. THE POPS OVER THE ATLANTA METRO AREA HAVE BEEN LOWERED INTO THE 30-40 PERCENT RANGE AND ALL OF NORTH GA WILL DROP TO AROUND 20 PERCENT AFTER MIDNIGHT. 16/39 SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... COLD FRONT IS PUSHING INTO NORTHWEST GEORGIA AT AFD TIME...WITH A LINE OF CONVECTION ROUGHLY FROM ATHENS TO THE SOUTH SIDE OF ATLANTA ALONG A WEAK SURFACE CONVERGENCE ZONE AND DIFFERENTIAL HEATING BOUNDARY /FROM MIDLEVEL CLOUDS UP NORTH/. DEEP UPPER TROUGH REMAINS IN PLACE OVER THE EASTERN PORTION OF THE COUNTRY BUT WILL BEGIN TO LIFT TOWARD THE END OF THE SHORT TERM...WITH THE FRONT PROGGED TO LINGER ACROSS CENTRAL GEORGIA THROUGH THURSDAY. CONCERN FOR THIS EVENING WILL BE MAINLY ABOUT CONVECTION...NAMELY COVERAGE AND INTENSITY. EXPECT CHANCES TO REMAIN PRETTY HIGH AS DEEP LAYER MOISTURE HAS INCREASED AHEAD OF THE FRONT. BUFR SOUNDINGS REMAIN FAIRLY SATURATED THROUGH THE EVENING AND OVERNIGHT HOURS AND WITH PLENTIFUL SBCAPE...IT IS MAINLY JUST A MATTER OF WHERE CONVECTION WILL BE ABLE TO GET GOING. CANNOT RULE OUT ISOLATED SEVERE STORMS WITH MARGINALLY SEVERE HAIL AS THE MAIN THREAT. DCAPE VALUES ARE BETWEEN 1000-1300 J/KG ACROSS NORTH GEORGIA AND ALSO ACROSS PORTIONS OF CENTRAL GEORGIA...WITH AREAS FROM METRO ATLANTA TO ATHENS TOO LOW FOR MUCH CONCERN. NEW TRENDS IN RAP DATA KEEP THE HIGH DCAPE VALUES IN PLACE DOWN SOUTH BUT DIMINISH THEM UP NORTH THROUGH THE AFTERNOON...SO BEST CHANCE FOR MARGINAL SEVERE WOULD LIKELY BE ACROSS PORTIONS OF CENTRAL GEORGIA. WIDESPREAD CLOUD COVER AND PLENTIFUL SURFACE MOISTURE WILL KEEP HIGH TEMPS TOMORROW A FEW DEGREES LOWER THAN NORMAL...WITH NEAR-NORMAL LOWS. TDP LONG TERM /FRIDAY THROUGH WEDNESDAY/... LONG WAVE TROUGH TO CONTINUE TO FILL OVER ERN CONUS FRI THRU SUN WHILE E-W ORIENTED RIDGE ALOFT BUILDS OVER SRN STATES. SHOULD SEE WARMING TEMPS AND LOWER POPS IN THIS PATTERN. ISOLD SHRA/TSRA STILL LIKELY BUT LESS COVERAGE THAN PREVIOUS DAYS. LARGE UPPER VORTEX AND TROUGH PROGGED BY 12Z MED RANGE MODELS TO SWING SOUTH FROM CANADA INTO ERN CONUS AGAIN MONDAY WITH PERIPHERY OF WESTERLIES AND WEAK FRONT DIPPING INTO GA ON TUES. EXPECT RETURN TO HIGHER POPS AND SLIGHTLY COOLER TEMP TUES/WED. MADE ONLY SMALL MODIFICATIONS TO POPS/WX AND TEMPS WITH MODEST ADJUSTMENTS TOWARD HPC GUIDANCE. SNELSON PREV LONG TERM DISCUSSION... /ISSUED 148 PM EDT WED JUL 9 2014/ /VALID THURSDAY NIGHT THROUGH TUESDAY/... THURSDAY AND FRIDAY....EXTENDED PERIOD BEGINS WITH EASTERN US TROF CENTERED NEAR 85 WEST AND REMNANT FRONTAL BOUNDARY DRAPED ACROSS CENTRAL GA. BOTH THE ECMWF AND GFS IN GOOD AGREEMENT WITH BOTH THE LOCATION OF THE FRONT AND DEPTH OF THE EASTERN TROF. END RESULT IS MOSTLY DIURNAL CONVECTION PARTICULARLY NEAR THE BOUNDARY ALONG AND SOUTH OF I85 WITH BEST CHANCES ON THURSDAY. MODEL CAPE VALUES ARE MODEST AND TYPICAL FOR SUMMERTIME PATTERN...HOWEVER PRECIPITABLE WATER VALUES PEAK ACROSS THE AREA ON THURSDAY BETWEEN 1.8 AND 2.0 INCHES WHICH COULD RESULT IN SOME EFFICIENT RAIN PRODUCING STORMS. DRIER AIR WORKS IN BEHIND THE FRONT ON FRIDAY SQUASHING THE BEST RAIN CHANCES TO THE SOUTH AND EAST PORTION OF THE AREA...I.E. CSG TO MCN AND POINTS SOUTH NEAR THE REMNANT FRONT. WEEKEND...THE GENERAL PATTERN PERSISTS INTO THE WEEKEND ACROSS THE EASTERN U.S. WITH THE TROF AXIS SHIFTING SLIGHTLY EAST OF GA BY SATURDAY AND SOME MID LEVEL RIDGING TRYING TO NOSE IN FROM THE WEST...WHILE THE REMNANT FRONT IS ALL BUT A DISTANT MEMORY. END RESULT WILL BE NEAR TO SLIGHTLY BELOW CLIMO POP CHANCES BOTH SATURDAY AND SUNDAY. CAVEAT HERE IS THAT PW VALUES SOAR UP TO NEAR OR SLIGHTLY ABOVE 2.0 INCHES MAKING FOR A MUGGY WEEKEND. STILL THINK THE GREATEST CHANCES WILL BE SOUTH AND EAST CLOSER TO WHERE SEA BREEZE ACTIVITY HAS THE BEST INFLUENCES LATE IN THE AFTERNOON. MONDAY AND TUESDAY...GFS AND ECMWF SLIGHTLY DIFFERENT BUT STILL GENERALLY AGREE THAT THE LARGER SCALE TROF WILL BE REINFORCED ACROSS THE REGION WITH ANOTHER FRONT APPROACHING. END RESULT WILL BE INCREASED POP CHANCES ON MONDAY AND PARTICULARLY TUESDAY. MUCH CAN HAPPEN BETWEEN NOW AND THEN SO WILL TREND HIGHER BUT NOT GO OVERBOARD. STELLMAN && .AVIATION... 06Z UPDATE... CONVECTION HAS MOSTLY CLEARED OUT THIS MORNING...A FEW MVFR CLOUDS MAY DEVELOP TOWARDS SUNRISE...BUT NOT CONFIDENT THAT THE MVFR DECK WILL GO BKN. DIURNAL CU EXPECTED TO DEVELOP BY MID MORNING AND SETTLE BETWEEN 040 AND 045. STALLED FRONTAL BOUNDARY SHOULD BE JUST TO THE SOUTH OF ATL...AND SHOULD PROVIDE THE MAIN FOCUS FOR TSRA TODAY. HOWEVER...ENOUGH CONFIDENCE SHRA/TSRA DEVELOPMENT WILL BE CLOSE ENOUGH TO THE AIRPORT FOR A PROB30. //ATL CONFIDENCE...06Z UPDATE... MEDIUM CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 89 69 91 68 / 50 30 30 20 ATLANTA 86 71 89 70 / 40 30 30 10 BLAIRSVILLE 82 63 84 61 / 40 30 20 20 CARTERSVILLE 86 67 89 65 / 40 30 20 10 COLUMBUS 90 73 92 72 / 60 30 30 10 GAINESVILLE 85 69 88 68 / 40 30 30 20 MACON 90 70 91 69 / 60 40 40 20 ROME 87 67 90 65 / 40 20 20 10 PEACHTREE CITY 87 68 89 67 / 50 30 30 10 VIDALIA 92 73 90 72 / 60 40 60 50 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
241 AM CDT Thu Jul 10 2014 ...Updated for Long Term... .SHORT TERM...(This evening through Thursday) ISSUED AT 205 PM CDT WED JUL 9 2014 The main challenge in the forecast tonight and Thursday is precipitation chances, extent, and thunderstorm severity. Surface-based thunderstorms are expected to develop across northeast Colorado in vicinity of, or just downstream of Cheyenne Ridge. The former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a small MCS would develop and roll southeast toward far west-central Kansas. The latest 12Z runs of both the models, however, are less aggressive with this idea. That being said, the HRRR (using WRF-ARW core) late morning runs insist on northeast Colorado activity evolving southeast through the evening across northeastern Kansas and eventually into our far northwestern zones (Syracuse to Scott City). We will maintain some Chance POPs in the far west-central Kansas counties north of Hwy 50 and generally west of Hwy 283 through the evening. Another MCS will either roll south-southeast out of Nebraska and interact with the western MCS or remain a separate entity all together and redevelop around 04-06Z across north central/central Kansas along a strengthening zone of warm frontogenesis in the 850-750mb layer. We will have some 40 POPs from Hays to Pratt in the 05-12Z time frame, but these may need to be raised early this evening if short term trends favor a more western scenario for potential MCS. The overall severe weather threat looks fairly minimal, despite a SLGT risk being issued by SPC. Any large hail threat would be confined to areas of far west-central Kansas (but more likely across northeastern Colorado and northwestern Kansas) with strong straight-line winds to 65 mph the most likely threat with any bowing segments during the mid to late evening hours. After that, a very heavy rain threat will develop during the overnight hours across central Kansas. It remains to be seen, though, how far west the core of the nocturnal MCS will be. It seems most likely this will stay across portions of central and south central Kansas just east of our forecast area (east of a Hays to Pratt line). Going in to the day Thursday, a warmer day is forecast with warmer overall temperatures in the lower troposphere (to +29C at 850mb as far east as the Hwy 283 corridor). This should allow surface temperatures late afternoon reaching close to, if not 100F (especially along/west of Hwy 83 where evapotransporation will be less). A fairly strong gradient will yield a windier day with south-southwest winds 20 to 23 knots sustained in the afternoon. .LONG TERM...(Friday through Wednesday) ISSUED AT 239 AM CDT THU JUL 10 2014 For Friday into Sunday, a broad area of upper level high pressure begins to weaken ahead of a strong upper level low moving southward from Central Canada and into the Upper Midwest. Weak surface low pressure will continue in far western Kansas then move slowly into central Kansas by Sunday. Some moisture convergence along the trough may be enough to set off a few thunderstorms mainly far west on Friday then a slight chance into much of western Kansas into Sunday. High temperatures will be warm and around 100 on Friday, and mid to upper 90s Saturday, then low to mid 90s for Sunday. Overnight lows will continue mild and in the low to mid 70s into Sunday morning. For Monday into mid week next week, the upper level low and associated cold upper trough will continue to build southward into the Upper Midwest and Central Plains with a cooling trend. Highs cool from around 90 on Monday into the 70s and 80s for Tuesday into Wednesday. Some small chances for thunderstorms continue with the best chances with and behind a cold front on Monday night and Tuesday. Overnight lows look to be in the 60s. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) ISSUED AT 1251 AM CDT THU JUL 10 2014 Winds will generally stay southerly with VFR conditions at DDC/GCK through the period as a lee trough remains in the lee of the Rockies. An outflow boundary will pass trough KGCK just after 06z (now) and could temporarily shift winds to northwest. At KHYS, thunderstorms will be in vicinity through 08z as low to mid level warm advection persists early this morning, with winds persisting from the southeast. Even at KHYS, CIGS and VISBYS will generally be VFR except briefly lower in any thunderstorms. && .PRELIMINARY POINT TEMPS/POPS... DDC 97 72 98 72 / 10 0 10 10 GCK 98 71 99 71 / 10 0 10 20 EHA 98 71 97 71 / 0 0 10 20 LBL 100 71 99 72 / 0 0 10 10 HYS 93 72 99 73 / 10 10 20 20 P28 93 72 98 75 / 20 0 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Kruse AVIATION...Finch
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
102 AM CDT Thu Jul 10 2014 ...Updated for aviation discussion... .SHORT TERM...(This evening through Thursday) ISSUED AT 205 PM CDT WED JUL 9 2014 The main challenge in the forecast tonight and Thursday is precipitation chances, extent, and thunderstorm severity. Surface-based thunderstorms are expected to develop across northeast Colorado in vicinity of, or just downstream of Cheyenne Ridge. The former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a small MCS would develop and roll southeast toward far west-central Kansas. The latest 12Z runs of both the models, however, are less aggressive with this idea. That being said, the HRRR (using WRF-ARW core) late morning runs insist on northeast Colorado activity evolving southeast through the evening across northeastern Kansas and eventually into our far northwestern zones (Syracuse to Scott City). We will maintain some Chance POPs in the far west-central Kansas counties north of Hwy 50 and generally west of Hwy 283 through the evening. Another MCS will either roll south-southeast out of Nebraska and interact with the western MCS or remain a separate entity all together and redevelop around 04-06Z across north central/central Kansas along a strengthening zone of warm frontogenesis in the 850-750mb layer. We will have some 40 POPs from Hays to Pratt in the 05-12Z time frame, but these may need to be raised early this evening if short term trends favor a more western scenario for potential MCS. The overall severe weather threat looks fairly minimal, despite a SLGT risk being issued by SPC. Any large hail threat would be confined to areas of far west-central Kansas (but more likely across northeastern Colorado and northwestern Kansas) with strong straight-line winds to 65 mph the most likely threat with any bowing segments during the mid to late evening hours. After that, a very heavy rain threat will develop during the overnight hours across central Kansas. It remains to be seen, though, how far west the core of the nocturnal MCS will be. It seems most likely this will stay across portions of central and south central Kansas just east of our forecast area (east of a Hays to Pratt line). Going in to the day Thursday, a warmer day is forecast with warmer overall temperatures in the lower troposphere (to +29C at 850mb as far east as the Hwy 283 corridor). This should allow surface temperatures late afternoon reaching close to, if not 100F (especially along/west of Hwy 83 where evapotransporation will be less). A fairly strong gradient will yield a windier day with south-southwest winds 20 to 23 knots sustained in the afternoon. .LONG TERM...(Thursday night through Wednesday) ISSUED AT 246 PM CDT WED JUL 9 2014 Thursday night/Friday: Minimums overnight Thursday will be quite mild - 70s - as southerly winds continue through the overnight in association with continued surface lee troughing. Friday will be a hot day with max values at 97-100F. There will be a slight chance for tstms from Hugoton to Hays and points west, but convection may remain out of the area and limited to eastern Colorado and into southwest Nebraska. Another mild night with widespread 70s for lows is expected heading into Saturday morning. Saturday and beyond: A slightly better chance of coverage of storms is expected Saturday as a frontal boundary sinks farther to the south across Kansas. Ahead of the front, temperatures will be quite hot with values around 100F. A weak cool down is expected Sunday as the front heads south and slightly cooler 850-hPa temperatures advect across the region. Will have to watch out for convection across the western zones in this upslope flow pattern. The EC indicates another shot for an MCS Monday, as northwesterly flow aloft and low-level upslope flow continues across the High Plains. The best chance for precip area-wide is expected Tuesday as a rather cold air mass (for July standards) moves across the Plains. The EC has been very consistent with this cool down and associated precipitation. 850-hPa temperatures by the middle portion of next decrease as low as 8-10C! Very pleasant and highly abnormal Summer weather in regards to temperatures is possible in about a week from now with highs in the 70/80s and lows possibly in the 50s! The front could slow down, so exact timing is in question. Stuck with the allblend temperature solution for now. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) ISSUED AT 1251 AM CDT THU JUL 10 2014 Winds will generally stay southerly with VFR conditions at DDC/GCK through the period as a lee trough remains in the lee of the Rockies. An outflow boundary will pass trough KGCK just after 06z (now) and could temporarily shift winds to northwest. At KHYS, thunderstorms will be in vicinity through 08z as low to mid level warm advection persists early this morning, with winds persisting from the southeast. Even at KHYS, CIGS and VISBYS will generally be VFR except briefly lower in any thunderstorms. && .PRELIMINARY POINT TEMPS/POPS... DDC 72 98 73 99 / 0 10 10 20 GCK 71 99 72 98 / 0 20 20 20 EHA 71 97 71 94 / 0 20 20 10 LBL 71 99 72 98 / 0 10 20 10 HYS 72 99 72 97 / 10 20 20 30 P28 72 98 74 100 / 0 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Sugden AVIATION...Finch
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1100 PM MDT Wed Jul 9 2014 UPDATED AVIATION SECTION .DISCUSSION... Update forthcoming. Satellite imagery shows moisture continuing to be advected over southwest Montana this evening where the airmass remains somewhat unstable. The resulting showers and isolated thunderstorms will persist through 06z, mainly south of a KDLN-KBZN line. Latest RUC run, as well as HRRR analysis, indicate convective activity will shift to the east after 06z and decrease in areal coverage and intensity. North of the KDLN-KBZN line the airmass is much more stable and no precipitation is expected overnight. Temperatures look on track. && .AVIATION... UPDATED 0500Z. VFR conditions are expected to continue across the area at least through Thursday evening. Clouds and showers will continue to diminish through 10Z across central Montana as a disturbance moves through the area. A weak cold front will accompany the disturbance, shifting the southwesterly winds more northwesterly from northwest to southeast over the central Montana plains between 09Z and 15Z. Clouds will then increase again after 18Z as the mid level flow becomes more northwesterly and brings moisture into the area from Canada. Surface winds will decrease during this time and there will be a chance of showers along the Canadian border. Coulston && .PREV DISCUSSION...Issued 232 PM MDT Wed Jul 9 2014 Today through Friday...Southwest Montana will become slightly unstable this afternoon as an increase in moisture should bring scattered thunderstorms to the area. Moderate shear could allow for the development of some stronger cells. Precipitable water is somewhat high meaning some storms could produce brief heavy rain. Activity diminishes by midnight tonight. Thursday and Friday look to be much of the same with the days starting out quiet before afternoon convection over far Southwest Montana. Temperatures will remain warm and winds may be a bit breezy at times. Friday night through Wednesday...The main upper level ridge of high pressure that is residing over the region will slowly be shifting/retrograde a bit more to the west from Saturday through Tuesday. As a result...the warmest temperatures will likely be staying west of the divide and over the Pacific Northwest. Never-the-less...it will still be quite warm/very warm for Saturday and Sunday...then seasonable/warm temperatures will reside over the region from Monday thru Wednesday. In terms of precipitation...no real organized areas of precipitation is expected from Friday through Sunday...other than some passing monsoonal moisture. Thus the chances for thunderstorms are generally isolated during this period...and mainly over Central and Southwest Montana. For Monday/Tuesday...the GFS tries to develop a bit more widespread thunderstorm activity along the front range of the Rockies and then southward into Southwest MT. Thus pops have been increased a bit...but overall coverage still looks to be scattered at this time. The thunderstorm activity starts to decrease a bit by next Wednesday...as the upper level ridge will start to shift/wobble back east a bit...also resulting in slightly warmer temperatures. Brusda && .PRELIMINARY POINT TEMPS/POPS... GTF 60 86 56 84 / 10 10 10 10 CTB 55 79 50 80 / 10 10 20 0 HLN 62 90 57 88 / 20 10 10 10 BZN 57 87 53 87 / 30 10 20 20 WEY 47 78 44 81 / 40 20 20 40 DLN 57 86 54 88 / 30 10 10 10 HVR 61 88 53 87 / 10 10 20 10 LWT 60 86 53 84 / 30 10 10 10 && .TFX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ weather.gov/greatfalls www.twitter.com/NWSGreatFalls www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
330 AM CDT THU JUL 10 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 330 AM CDT THU JUL 10 2014 TEMPERATURES AND TSTM CHANCES WILL PROVIDE THE PRIMARY FORECAST CHALLENGES IN THIS PERIOD. LARGE SCALE PATTERN SHOULD UNDERGO SOME CHANGES. UPPER LEVEL RIDGE INITIALLY CENTERED OVER THE FOUR CORNERS REGION EXPANDS EASTWARD THROUGH SATURDAY AS A STRONG SHORTWAVE MOVES ACROSS CANADA. THE CENTER OF THE RIDGE THEN RETROGRADES INTO EARLY NEXT WEEK WHILE FLOW AMPLIFIES. TOWARD THE END OF THE PERIOD A CLOSED LOW AT 500 MB WILL DROP DOWN FROM CANADA INTO THE GREAT LAKES REGION. TODAY...SOUTHERLY SURFACE WINDS WILL INCREASE ACROSS THE CENTRAL PLAINS AS HIGH PRESSURE CONTINUES TO MOVE OFF TO THE EAST. MAIN AREA OF TSTMS SHOULD MOVE OUT OF THE FORECAST AREA BY AROUND SUNRISE...BUT WILL HOLD ONTO SOME LOW POPS FOR PARTS OF SOUTHEAST NEBRASKA INTO MID MORNING. EXPECT HIGHS TO BE MAINLY IN THE LOWER TO MID 80S. TONIGHT...BETTER MOISTURE WILL BE IN PLACE BOTH SURFACE AND ALOFT. PRECIPITABLE WATER VALUES INCREASE INTO THE 1.50 TO 2.00 RANGE AND THE 00Z NAM SUGGESTS SOME VALUES OVER 2.00 INCHES. COMBINATION OF INCREASING MOISTURE AND A 50 KNOT LOW LEVEL JET WITH WEST/NORTHWEST MID LEVEL FLOW SHOULD LEAD TO A TSTM COMPLEX SOMEWHERE IN THE REGION. MODELS ARE NOT IN VERY GOOD AGREEMENT ON LOCATION. FOR NOW TENDED TO FAVOR 00Z GFS FOR PLACEMENT OF HIGHEST RAIN CHANCES AND HEAVIEST RAIN AMOUNTS. SO...THAT KEEPS HIGHEST POPS FOR ABOUT THE NORTH OR NORTHEAST HALF OF THE AREA. STORMS MAY LINGER INTO FRIDAY MORNING...THEN WEAKEN. HIGHS SHOULD REACH 85 TO 90 MOST LOCATIONS WITH SOME LOWER 90S NEAR THE KANSAS BORDER. FRONTAL BOUNDARY IS FORECAST TO SAG SOUTHWARD FRIDAY NIGHT INTO SATURDAY. KEPT POPS MOSTLY 30 TO 50 PERCENT AS OUR AREA WILL BE NORTH OF THE FRONT IN A FAVORABLE REGIME FOR PCPN... ESPECIALLY LATE FRIDAY NIGHT. HIGHS SATURDAY WILL PROBABLY BE A BIT COOLER WITH MID 80S NORTH AND UPPER 80S SOUTH. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 330 AM CDT THU JUL 10 2014 HIGH TEMPERATURES WILL BE A LITTLE BELOW NORMAL AT THE BEGINNING OF THIS PERIOD...THEN COOL TO WELL BELOW TYPICAL VALUES FOR MID JULY. HIGHLY AMPLIFIED FLOW WILL ALLOW A CANADIAN AIRMASS TO DROP DOWN INTO THE AREA AS RIDGE AXIS ALOFT BUILDS OVER WESTERN NORTH AMERICA. KEPT SOME MENTION OF PCPN THROUGH TUESDAY...THEN WENT WITH POPS 14 OR LESS AS COOLER AND DRIER AIR SETTLES IN. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1150 PM CDT WED JUL 9 2014 POCKETS OF CONVECTION CONTINUE JUST WEST OF THE FORECAST AREA AT 05Z WITH KLNK STILL REPORTING OCCASIONAL SHOWERS. RAP STILL INDICATES A GRADUAL EASTWARD SHIFT OF THE CENTRAL NEBRASKA SYSTEM AS LOW LEVEL JET AND MOISTURE ADVECTION TRANSLATE INTO EASTERN NEBRASKA BY 12Z AND CONTINUES THROUGH THE MORNING. HAVE LIMITED A PERIOD OF CONVECTION AT KLNK DURING THE EARLY MORNING AND AT KOMA AFTER 15Z. KOFK IS EXPECTED TO BE ON EDGE OF ACTIVITY THROUGH THE PERIOD. LIMITED CONFIDENCE AT THIS TIME HOWEVER AND WILL NEED TO MONITOR DEVELOPMENT TRENDS NEXT FEW HOURS TO SEE IF RAP IS HEADING IN THE RIGHT DIRECTION WITH ITS SOLUTION. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
233 AM CDT THU JUL 10 2014 .SYNOPSIS... ISSUED AT 318 PM CDT WED JUL 9 2014 H5 ANALYSIS FROM THIS MORNING HAS A CONTINUATION OF THE RIDGE/TROUGH REGIME ACROSS THE CONUS. A TROUGH OF LOW PRESSURE EXTENDED SOUTH FROM NORTHERN CANADA INTO THE OHIO VALLEY. RIDGING EXTENDED NORTH FROM HIGH PRESSURE LOCATED OVER SRN UTAH INTO NORTHERN PORTIONS OF ALBERTA AND SASKATCHEWAN. ACROSS THE CENTRAL AND NORTHERN PLAINS...A NICE 40 TO 45 KT SPEED MAX EXTENDED FROM WESTERN NEBRASKA NWD INTO WESTERN SD AND MT. THIS FEATURE ALONG WITH A VERY WEAK CAP...HAS SUPPORTED CONVECTION ACROSS NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING AND THIS AFTERNOON. SO FAR...STORMS HAVE LARGELY REMAINED BELOW SEVERE LIMITS THROUGH THE MORNING...HOWEVER...WITH INCREASED HEATING THIS AFTERNOON...STORMS HAVE INCREASED IN STRENGTH GIVEN THE DECENT DEGREE OF BULK SHEAR. AS OF 3 PM CDT...UNDER PARTLY TO MOSTLY CLOUDY SKIES...TEMPERATURES RANGED FROM 62 IN RAIN COOLED AIR AT AINSWORTH...TO 90 AT IMPERIAL. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 318 PM CDT WED JUL 9 2014 TONIGHT AND THURSDAY...PRECIPITATION CHANCES TONIGHT AND TOMORROW AFTERNOON ARE THE MAIN FORECAST CONCERNS. FOR TONIGHT...THUNDERSTORM CHANCES WILL CONTINUE THROUGH LATE EVENING AND MAY POSSIBLY CONTINUE INTO THE OVERNIGHT WITH THE PRESENCE OF A LOW LEVEL JET ANCHORED ACROSS SOUTHERN NEBRASKA. ATTM CONFIDENCE IN PCPN PERSISTING INTO THE OVERNIGHT IS NOT HIGH ATTM AS THE NAM SOLN IS A TAD FARTHER EAST WITH ITS LOW LEVEL JET AND THE HRRR SOLN PUSHES THIS ACTIVITY SOUTH OF THE AREA BY LATE EVENING. THURSDAY MORNING WILL BE QUIET ACROSS WESTERN AND NORTH CENTRAL NEBRASKA...HOWEVER...BY THURSDAY AFTERNOON...SURFACE HEATING AND THE APPROACH OF AN UPPER LEVEL DISTURBANCE...WILL STEEPEN LAPSE RATES ACROSS THE WESTERN FORECAST AREA BY 21Z THURSDAY. H85 TO H7 LAPSE RATES WILL APPROACH 9.5 TO 10C THURSDAY AFTERNOON. IN ADDITION...THE CAP WILL WEAKEN INVOF A SURFACE TROUGH MID AFTERNOON THURSDAY. ATTM...THUNDERSTORMS ARE EXPECTED TO INITIATE MID AFTERNOON IN THE PANHANDLE AND TRACK EAST. ATTM...WILL CONFINE PRECIP CHANCES TO THE WESTERN HALF OF THE FORECAST AREA...AS LOCATIONS IN THE EAST ARE STRONGLY CAPPED THURSDAY AFTERNOON. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 318 PM CDT WED JUL 9 2014 THURSDAY NIGHT THROUGH SATURDAY NIGHT...THE MAIN FORECASTING CHALLENGE CONTINUES TO BE PRECIPITATION CHANCES AS THE FORECAST AREA REMAINS IN NORTHWESTERLY AND WEST NORTHWESTERLY FLOW ALOFT. A FRONTAL BOUNDARY WILL PUSH SOUTH ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THURSDAY NIGHT AND WILL BE THE FOCUS FOR SHOWER AND THUNDERSTORM DEVELOPMENT THURSDAY NIGHT INTO FRIDAY MORNING. STRONG STORMS WILL BE POSSIBLE INVOF THE FRONT THURSDAY EVENING...WITH 35 TO 45 KTS OF DEEP LAYER SHEAR THURSDAY EVENING. INTO THE OVERNIGHT HOURS...A STRONG LOW LEVEL JET EXTENDING FROM SWRN NEBRASKA INTO NERN NEBRASKA...WILL ALLOW THE THREAT FOR STORMS TO CONTINUE...HOWEVER...THE THREAT FOR SEVERE STORMS WILL DIMINISH AS DEEP LAYER SHEAR DECREASES TO 20 TO 30 KTS OVERNIGHT. ON FRIDAY...THE FRONT WILL STALL EITHER IN SOUTHWESTERN KS TO SERN NEBRASKA PER THE NAM SOLN OR FROM NWRN KS INTO SOUTH CENTRAL NEBRASKA PER THE GFS SOLN. THE GFS GENERATES A NICE AREA OF POST FRONTAL MID LEVEL LIFT NORTH OF THE FRONT ACROSS CENTRAL AND NORTHERN NEBRASKA FRIDAY AFTERNOON INTO FRIDAY NIGHT...WHILE THIS IS LARGELY ABSENT IN THE NAM SOLN. EVEN WITH A MODEL COMPROMISE AND THE FRONT ACROSS NORTHERN KS...DECENT MID LEVEL LIFT AND WARM AIR ADVECTION NORTH OF THE FRONT ACROSS THE FORECAST AREA PER THE GFS SOLN IS HARD TO IGNORE. WITH THIS IN MIND...WILL CONTINUE POPS FRIDAY AFTERNOON INTO FRIDAY NIGHT. ON SATURDAY...THE FRONT WILL WASH OUT...ALLOWING SRLY WINDS TO SURGE NORTH INTO THE PANHANDLE. THETA E RIDGING AND INCREASED MOISTURE WILL BUILD NORTH INTO THE PANHANDLE AS WELL LEADING TO 1500 TO 2500 J/KG CAPES SATURDAY AFTERNOON. THUNDERSTORMS SHOULD INITIATE QUICKLY LATE SAT AFTERNOON...WITHIN A WEAKLY CAPPED AREA IN THE PANHANDLE AND WESTERN SANDHILLS. THIS ACTIVITY WILL TRANSITION EAST SAT EVENING AND HAS THE POTENTIAL TO BE SEVERE WITH FCST DEEP LAYER SHEAR OF 40 TO 50 KTS. SUNDAY THROUGH WEDNESDAY...A STRONG UPPER LEVEL LOW OVER THE HUDSON BAY WILL DROP SOUTH INTO WESTERN ONTARIO. THIS WILL FORCE A STRONG NRN STREAM COLD FRONT INTO THE REGION SUNDAY AFTERNOON INTO SUNDAY NIGHT. THUNDERSTORMS MAY DEVELOP ALONG AND BEHIND THIS FEATURE SUNDAY AND SUNDAY NIGHT AND WILL SHIFT SOUTH BY MONDAY MORNING. HIGH AMPLITUDE NORTHWESTERLY FLOW ALOFT WILL DEVELOP ACROSS THE HIGH PLAINS MONDAY. ANY STORMS WHICH DO FIRE TO THE WEST UNDERNEATH THE THETA E AXIS...SHOULD STAY MAINLY OFF TO THE WEST OF THE FORECAST AREA GIVEN THE NWRLY STEERING WINDS. WITH THIS IN MIND...WILL KEEP THE HIGHEST POPS IN THE PANHANDLE AND FAR SOUTHWEST. MUCH COOLER TEMPERATURES WILL DEVELOP BEHIND THE FRONT WITH 70S FOR HIGHS TUESDAY AND WEDNESDAY OF NEXT WEEK AND POPS GENERALLY CONFINED TO THE HIGHER TERRAIN OF COLORADO AND SERN WYOMING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 232 AM CDT THU JUL 10 2014 IFR CEILING HAVE ENDED AT KLBF...WHICH WERE MOST LIKELY INDUCED BY OUTFLOW WINDS FROM THUNDERSTORMS EAST OF THE TERMINAL. WILL NEED TO MONITOR THE NEXT FEW HOURS HOWEVER. VFR CONDITIONS SHOULD REVAIL UNTIL THE NEXT ROUND OF THUNDERSTORMS INPACTS WESTERN NEBRASKA AFTER 21Z. HAVE INCLUDED A TEMPO FOR 5SM TSRA AT KVTN FROM 23Z-03Z AND A PROB30 FOR KLBF FROM 01Z-05Z. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CLB SHORT TERM...CLB LONG TERM...CLB AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1151 PM CDT WED JUL 9 2014 .SHORT TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 319 PM CDT WED JUL 9 2014 MODELS IN RELATIVELY DECENT AGREEMENT LARGE SCALE FLOW OVER MOST OF THE CONUS WILL BE NEAR ZONAL WHILE A POTENT SHORTWAVE TROF RUSHES ACROSS CANADA. HEADING INTO THE WEEKEND THEN...PATTERN IS PROGGED TO BEGIN AMPLIFYING WITH AN UPSTREAM RIDGE BECOMING ESTABLISHED OVER THE WRN CONUS BY SAT AFTN. MEANWHILE...GULF MOISTURE ADVECTION WILL BEGIN IN EARNEST LATER TONIGHT AS SFC HIGH PRESSURE SLIDES EAST AND ALLOWS MOISTURE TO SLIDE UP ALONG THE WRN HIGH PLAINS. APPEARS THAT MOISTURE RICH ENVIRONMENT WILL BE IN PLACE THEN THRU THE FCST PD. CURRENT RADAR MOSAIC WAS SHOWING CLUSTER OF TSTMS FROM S-CNTRL SD INTO N-CNTRL NEB MOVING SE WITHIN POCKET OF MID LYR ISENTROPIC UPGLIDE. LATEST HRRR SUGGESTING AREA OF CONVECTION WILL GRADUALLY INCREASE IN AREAL COVERAGE AND EXPAND INTO THE WRN CWA THEN EARLY THIS EVENING AND POSSIBLY THE REST OF THE CWA OVERNIGHT. OTHERWISE...MAIN ISSUE IS PINNING DOWN PLACEMENT/TIMING THUNDER POPS THE NEXT COUPLE DAYS. HOWEVER...REASONABLE ASSUME ON THUR NIGHT/FRI NIGHT...LLVL JET AND FAVORABLE FRONTOGENETIC FORCING/THETA-E CONVG WITHIN BNDRY LYR WILL HELP INDUCE NOCTURNAL TSTM ACTIVITY. AS FOR SVR TSTMS...NAM IS ADVERTISING POSSIBLE SVR DEVELOPMENT THUR NIGHT OVER N-CNTRL NEB WITH MUCAPES 2000-2500 J/KG AND ADEQUATE VERTICAL SHEAR. ALL THIS IN PART TO LEESIDE SFC LOW AND ATTENDANT THERMAL BNDRY EXTENDING FROM ABOUT NERN CO TO NERN SD. GFS INSTABILITY/SHEAR AT THAT TIME THOUGH IS SUBSTANTIALLY WEAKER. NEVERTHELESS...SITUATION BEARS WATCHING. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 319 PM CDT WED JUL 9 2014 RATHER GOOD AGREEMENT BTWN CMC/ECM/GFS EARLY ON THAT AMPLIFICATION WILL CONTINUE INTO EARLY NEXT WEEK WITH A HIGHLY ANOMALOUS UPPER TROF OVER THE ERN CONUS AND UPSTREAM RIDGE OVER THE WRN CONUS. AT THIS POINT DETERMINISTIC ECM/GFS AS WELL AS ECMENS/CMCENS ALL INDICATE LARGE SCALE FLOW WILL BECOME STAGNANT AND ALLOW A RATHER COOL AIRMASS FOR THIS TIME OF THE SEASON TO EXPAND SWD INTO THE REGION DAY 6 AND 7. EXPECT THEN A GOOD CHUNK OF THE CNTRL PLAINS WILL SEE WELL BELOW NORMAL AFTN TEMPS TUES AND WED. GOING POPS IN THE EXT PDS LOOK GOOD FOR NOW SO NO MAJOR CHANGES PLANNED. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1150 PM CDT WED JUL 9 2014 POCKETS OF CONVECTION CONTINUE JUST WEST OF THE FORECAST AREA AT 05Z WITH KLNK STILL REPORTING OCCASIONAL SHOWERS. RAP STILL INDICATES A GRADUAL EASTWARD SHIFT OF THE CENTRAL NEBRASKA SYSTEM AS LOW LEVEL JET AND MOISTURE ADVECTION TRANSLATE INTO EASTERN NEBRASKA BY 12Z AND CONTINUES THROUGH THE MORNING. HAVE LIMITED A PERIOD OF CONVECTION AT KLNK DURING THE EARLY MORNING AND AT KOMA AFTER 15Z. KOFK IS EXPECTED TO BE ON EDGE OF ACTIVITY THROUGH THE PERIOD. LIMITED CONFIDENCE AT THIS TIME HOWEVER AND WILL NEED TO MONITOR DEVELOPMENT TRENDS NEXT FEW HOURS TO SEE IF RAP IS HEADING IN THE RIGHT DIRECTION WITH ITS SOLUTION. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE LONG TERM...DEE AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
317 AM EDT THU JUL 10 2014 .SYNOPSIS...A WEAKENING COLD FRONT WILL MOVE INTO THE AREA TODAY THEN DRIFT TOWARD THE COAST FRIDAY. WEAK HIGH PRESSURE WILL SETTLE OVER THE REGION SATURDAY. && .NEAR TERM /OVERNIGHT/... AS OF 1045 PM WEDNESDAY... CYCLONIC FLOW ALOFT WILL PREVAIL ACROSS THE REGION OVERNIGHT... FOSTERING A POTENTIAL FOR DPVA ASSOCIATED WITH SMALL AMPLITUDE DISTURBANCES TRACKING EAST FROM THE TN/OH VALLEY INTO THE MID- ATLANTIC AND NORTH CAROLINA. GIVEN THE PRESENCE OF MARGINAL NOCTURNAL INSTABILITY (500-1000 J/KG MUCAPE) AND THE PRESENCE OF A SHORTWAVE JUST UPSTREAM OVER TN/KY (PER RAP DATA AND WV IMAGERY)... WILL CONTINUE TO INDICATE A SLIGHT CHANCE OF SHOWERS/STORMS THROUGHOUT THE NIGHT. EXPECT LOWS IN THE LOWER 70S. -VINCENT && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 230 PM WEDNESDAY... SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR AGAIN ON THURSDAY AS A SERIES OF WEAK DISTURBANCES MOVE NE ACROSS OUR AREA IN ADVANCE OF THE MID-LEVEL TROUGH AXIS TO OUR WEST. AT THE SFC...THE COLD FRONT CURRENTLY TO OUR NW WILL DROP SOUTH AND MERGE WITH THE PIEDMONT TROUGH...PROVIDING A LOW LEVEL FOCUS FOR CONVECTION INITIATION. NOTED THAT GUIDANCE SHOWS AN AXIS OF HIGH PWAT (AROUND 2 INCHES) WILL PERSIST ACROSS THE EASTERN 2/3 OF OUR CWA DURING THE AFTERNOON INTO THE EVENING...TRENDING LOWER TO AROUND 1.5 INCHES ACROSS THE TRIAD. MEANWHILE...DEEP LAYER SHEAR WILL BE SIMILAR TO TODAY...25KT OR LESS. THUS...WHILE WE CAN`T RULE OUT THE POTENTIAL FOR AN ISOLATED STRONG WIND GUST OR TWO...THE MAIN IMPACTS MAY INSTEAD BE HEAVY RAIN INVOF OF THE BELT OF HIGH PWAT...AND THE POTENTIAL FOR LOCALIZED POOR DRAINAGE FLOODING WITH ANY OF THE SLOWER CELLS OR LOCATIONS THAT SEE REPETITIVE DOWNPOURS. GIVEN THIS MOISTURE PROFILE...LOOK FOR THE BEST COVERAGE AND THUS HIGHEST POPS TO BE EAST OF THE TRIAD. SIMILAR TO TODAY...HIGHS WILL BE DEPENDENT ON CLOUD COVERAGE...WHICH MAY BE MORE WIDESPREAD ACROSS OUR CWA TOMORROW COMPARED TO TODAY. HIGHS IN THE MID-UPR 80S AND LOWS THURSDAY NIGHT IN THE UPPER 60S TO AROUND 70. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 310 AM THURSDAY... SATURDAY THROUGH SUNDAY NIGHT: THE WEAK MID LEVEL TROUGH AXIS IS PROGGED TO PUSH TO THE EAST AND SOUTH OF CENTRAL NC BY SATURDAY MORNING. AT THE SURFACE THE LINGERING WEAK SURFACE TROUGH ACROSS EASTERN NC IS EXPECTED TO SLOWLY RETROGRADE WESTWARD ACROSS THE PIEDMONT (REMAINING VERY WEAK)... AS THE MID LEVEL RIDGE OVER THE SOUTHERN PLAINS AND INTERMOUNTAIN WEST IS EXPECTED TO NUDGE EASTWARD AND INTO OUR AREA. THIS COUPLED WITH DRIER AIR BEHIND THE DEPARTING MID LEVEL TROUGH AND LACK OF A GOOD TRIGGER WILL LEAD TO GENERALLY ISOLATED CONVECTION ON SATURDAY... WITH THE BEST CHANCE ACROSS OUR FAR EAST/SOUTHEAST (BEST REMAINING MOISTURE AND WEAK CONVERGENCE EARLY IN THE AFTERNOON). WITH AFTERNOON LOW LEVEL THICKNESS VALUES EXPECTED TO BE AROUND 1420 METERS AND LACK OF GOOD CONVECTIVE COVERAGE THINK WE WILL SEE TEMPS AT LEAST CLIMB INTO THE UPPER 80S/NEAR 90 NORTH/NORTHWEST TO THE LOWER 90S SOUTH. EXPECT GENERALLY DRY CONDITIONS OVERNIGHT. HOWEVER... WITH CENTRAL NC ON THE PERIPHERY OF THE MID LEVELE RIDGE AND MOISTURE EXPECTED TO BE INCREASE CANNOT COMPLETELY RULE OUT A WEAK PERTURBATION MOVING THROUGH THE MID LEVEL FLOW AND SETTING OFF A FEW ISOLATED SHOWERS/STORMS. EXPECT LOWS SUNDAY MORNING WILL BE IN THE UPPER 60S TO LOWER 70S. CHANCES FOR SHOWERS AND STORMS WILL INCREASE A BIT ON SUNDAY... ALTHOUGH STILL LOW CHANCE/SLIGHT CHANCE POPS AT THIS TIME. EXPECT WE WILL BEGIN TO SEE A FULL LATITUDE EASTERN U.S. TROUGH DEVELOP. WHILE THE MID LEVEL RIDGE WILL GENERALLY HOLD ACROSS OUR AREA ON SUNDAY... WE WILL SEE THE MID LEVEL RIDGE CENTER BEGIN TO RETREAT WESTWARD AND SETUP ACROSS THE WESTERN U.S. THIS COUPLED WITH INCREASING MOISTURE THROUGHOUT THE COLUMN AND A SHARPENING SURFACE TROUGH WILL LEAD TO A LITTLE BIT BETTER CHANCE OF SHOWERS AND STORMS FOR SUNDAY AFTERNOON/EVENING... WITH THE BEST CHANCES ACROSS THE NORTH/NORTHWEST PIEDMONT. AFTERNOON LOW LEVEL THICKNESS VALUES ARE EXPECTED TO RISE BY ANOTHER 5 TO 10 METERS OVER SATURDAY AFTERNOON. THUS... EXPECT WE WILL SEE HIGH TEMPS IN THE LOWER TO MID 90S (MAYBE EVEN A FEW UPPER 90S ACROSS THE SANDHILLS). LOWS MONDAY MORNING ARE EXPECTED TO BE GENERALLY IN THE LOWER 70S. MONDAY THROUGH WEDNESDAY: A DEEP TROUGH IS EXPECTED TO DEVELOP ACROSS THE EASTERN HALF OF THE COUNTRY EARLY NEXT WEEK... WITH A DEEP VORTEX EXPECTED TO DIVE SOUTHWARD OUT OF CANADA AND ACROSS THE NORTHERN PLAINS/UPPER MIDWEST AND GREAT LAKES REGION. THIS SHOULD RESULT IN THE INCREASING LIKELIHOOD OF SHOWERS AND STORMS EARLY NEXT WEEK ACROSS CENTRAL NC.... AS A STRONG COLD FRONT MOVES INTO THE AREA EARLY NEXT WEEK (LOOKING LIKE LATE TUESDAY INTO TUESDAY NIGHT OR EARLY WEDNESDAY). THUS... WILL SHOW CHANCES FOR SHOWERS AND STORMS INCREASING EARLY NEXT WEEK... PEAKING ON TUESDAY AFTERNOON/EVENING. WITH MODELS NOW SHOWING THE FRONT PUSHING TO THE SOUTH OF THE AREA ON WEDNESDAY WILL LOWER POPS... BUT STILL KEEPING AT LEAST A SLIGHT CHANCE NORTH TO CHANCE SOUTH MENTIONED AS WE ARE TALKING ABOUT DAY 7 OF THE FORECAST AND DEALING WITH AN ANOMALOUS SETUP FOR THIS TIME OF YEAR. IN FACT WE COULD EVEN SEE MORE OF AN ORGANIZED SEVERE THREAT AS MID LEVEL FLOW IS EXPECTED TO STRENGTHEN AS THE SYSTEM APPROACHES. HIGH TEMPS AHEAD OF THE FRONT MAY BE SUPPRESSED SOME BY CONVECTION... BUT STILL THINK LOWER TO MID 90S WILL STILL BE POSSIBLE ON MONDAY AND POSSIBLY TUESDAY (MAYBE A CATEGORY COOLER ON TUESDAY DEPENDING ON TIMING OF THE PRECIP/FRONT). HIGHS TEMPS WEDNESDAY WILL BE COOLER IF THE FRONT INDEED PUSHES THROUGH THE AREA. FOR NOW WILL GO WITH HIGHS IN THE MID TO UPPER 80S. LOWS EARLY TO MID NEXT WEEK ARE EXPECTED TO BE IN THE LOWER TO MID 70S IN ADVANCE OF THE FRONT AND UPPER 60S TO LOWER 70S ON WEDNESDAY MORNING. && AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 105 AM THURSDAY... A MOIST AND UNSTABLE AIR MASS WILL SUPPORT THE DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVERNIGHT THROUGH THURSDAY NIGHT AS AN UPPER LEVEL TROUGH AND ATTENDANT SURFACE BOUNDARY MOVES ACROSS THE AREA. THE SHOWERS AND STORMS WILL BE MOST NUMEROUS DURING THE AFTERNOON AND EARLY EVENING HOURS. EXPECT MVFR/IFR VISIBILITIES AND CEILINGS IN VICINITY OF THE HEAVIER SHOWERS AND STORMS. AWAY FROM THE CONVECTION...EXPECT VFR CONDITIONS WITH SFC WINDS PREDOMINATELY WEST-SOUTHWEST AT LESS THAN 10 KTS. IMPROVING AVIATION CONDITIONS ANTICIPATED FRIDAY THROUGH SATURDAY AS A SLIGHTLY DRIER MORE STABLE AIR MASS COVERS MOST OF THE REGION. SCATTERED AFTERNOON-EARLY EVENING CONVECTION WILL STILL BE PROBABLE IN VICINITY OF KFAY AND KRWI FRIDAY WHERE AVAILABLE MOISTURE AND LOW LEVEL INSTABILITY WILL BE BEST COMPARED TO THE PIEDMONT. ANY CONVECTION SATURDAY IS EXPECTED TO BE ISOLATED. BY SUNDAY AND MONDAY ...REMNANTS OF DECAYING THUNDERSTORM COMPLEXES ORIGINATING IN THE MIDWEST MAY BEGIN TO AFFECT CENTRAL NC...LEADING TO A SLIGHTLY BETTER CHANCE FOR SCATTERED CONVECTION AND ASSOCIATED MVFR CONDITIONS. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS NEAR TERM...VINCENT SHORT TERM...NP LONG TERM...BSD AVIATION...WSS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
105 AM EDT THU JUL 10 2014 .SYNOPSIS...A WEAKENING COLD FRONT WILL MOVE INTO THE AREA TODAY THEN DRIFT TOWARD THE COAST FRIDAY. WEAK HIGH PRESSURE WILL SETTLE OVER THE REGION SATURDAY. && .NEAR TERM /OVERNIGHT/... AS OF 1045 PM WEDNESDAY... CYCLONIC FLOW ALOFT WILL PREVAIL ACROSS THE REGION OVERNIGHT... FOSTERING A POTENTIAL FOR DPVA ASSOCIATED WITH SMALL AMPLITUDE DISTURBANCES TRACKING EAST FROM THE TN/OH VALLEY INTO THE MID- ATLANTIC AND NORTH CAROLINA. GIVEN THE PRESENCE OF MARGINAL NOCTURNAL INSTABILITY (500-1000 J/KG MUCAPE) AND THE PRESENCE OF A SHORTWAVE JUST UPSTREAM OVER TN/KY (PER RAP DATA AND WV IMAGERY)... WILL CONTINUE TO INDICATE A SLIGHT CHANCE OF SHOWERS/STORMS THROUGHOUT THE NIGHT. EXPECT LOWS IN THE LOWER 70S. -VINCENT && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 230 PM WEDNESDAY... SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR AGAIN ON THURSDAY AS A SERIES OF WEAK DISTURBANCES MOVE NE ACROSS OUR AREA IN ADVANCE OF THE MID-LEVEL TROUGH AXIS TO OUR WEST. AT THE SFC...THE COLD FRONT CURRENTLY TO OUR NW WILL DROP SOUTH AND MERGE WITH THE PIEDMONT TROUGH...PROVIDING A LOW LEVEL FOCUS FOR CONVECTION INITIATION. NOTED THAT GUIDANCE SHOWS AN AXIS OF HIGH PWAT (AROUND 2 INCHES) WILL PERSIST ACROSS THE EASTERN 2/3 OF OUR CWA DURING THE AFTERNOON INTO THE EVENING...TRENDING LOWER TO AROUND 1.5 INCHES ACROSS THE TRIAD. MEANWHILE...DEEP LAYER SHEAR WILL BE SIMILAR TO TODAY...25KT OR LESS. THUS...WHILE WE CAN`T RULE OUT THE POTENTIAL FOR AN ISOLATED STRONG WIND GUST OR TWO...THE MAIN IMPACTS MAY INSTEAD BE HEAVY RAIN INVOF OF THE BELT OF HIGH PWAT...AND THE POTENTIAL FOR LOCALIZED POOR DRAINAGE FLOODING WITH ANY OF THE SLOWER CELLS OR LOCATIONS THAT SEE REPETITIVE DOWNPOURS. GIVEN THIS MOISTURE PROFILE...LOOK FOR THE BEST COVERAGE AND THUS HIGHEST POPS TO BE EAST OF THE TRIAD. SIMILAR TO TODAY...HIGHS WILL BE DEPENDENT ON CLOUD COVERAGE...WHICH MAY BE MORE WIDESPREAD ACROSS OUR CWA TOMORROW COMPARED TO TODAY. HIGHS IN THE MID-UPR 80S AND LOWS THURSDAY NIGHT IN THE UPPER 60S TO AROUND 70. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... AS OF 245 PM WEDNESDAY... FOR FRI THROUGH SAT NIGHT: THE WEAKENING MID LEVEL TROUGH AXIS SHIFTS EAST OF THE SRN APPALACHIANS FRI... BEFORE SWEEPING OVERHEAD FRI NIGHT AND TO OUR EAST SAT. THE WEAK SURFACE TROUGH WILL ROUGHLY FOLLOW THIS PACE AS WELL... SETTLING OVER THE COASTAL CAROLINAS BY SAT MORNING BEFORE LARGELY DISSIPATING. THE EASTERN HALF OF NC WILL REMAIN WITHIN SUFFICIENTLY DEEP MOISTURE FRI FOR MAINLY AFTERNOON/EVENING SHOWERS AND STORMS... WHILE A DRIER COLUMN... SLIGHT RISE IN HEIGHTS ALOFT... AND DOWNSLOPE LOW LEVEL FLOW OVER THE WEST WILL LIMIT CONVECTION THERE... A PATTERN SUPPORTED BY THE LATEST SREF PROBABILITIES OF CONVECTIVE PRECIP. THE GFS SHOWS MUCAPE PEAKING AT 1500-2000 J/KG BUT SUBPAR DEEP LAYER SHEAR OF JUST AROUND 20 KTS OR SO... SO EXPECT ANOTHER ROUND OF WEAKLY FORCED AND SLOW MOVING MULTICELL CLUSTER WITH SUPPRESSED SEVERITY BUT THE POTENTIAL FOR TRAINING CELLS AND LOCALLY HEAVY RAIN GIVEN THE PW HOLDING NEAR 2.0 INCHES EAST OF HIGHWAY 1. THE SHEAR AXIS BROADENS AND WEAKENS FURTHER ON SAT WITH MINOR RISES IN HEIGHTS ALOFT. ANY TRACE OF THE SURFACE TROUGH IS TOUGH TO DETECT ON THE MODEL OUTPUT WITH A FAIRLY UNIFORM LIGHT LOW LEVEL FLOW FROM THE S AND SE. MODELS SHOW CENTRAL AND WRN NC WITHIN A RELATIVE PW MINIMUM... BETWEEN THE 1.5+ INCH VALUES OVER COASTAL NC AND ERN SC... AND THE HIGHER VALUES PUSHING INTO THE OH VALLEY ASSOCIATED WITH WHAT WILL LIKELY BE AN MCS CROSSING THE MIDWEST AND SOUTHERN END OF THE GREAT LAKES SAT/SAT NIGHT. BUT ANY AMOUNT OF ATLANTIC-SOURCE LOW LEVEL INFLOW COMBINED WITH HEATING COULD GENERATE DISORGANIZED ISOLATED TO SCATTERED PULSE CONVECTION IN THE AFTERNOON. WILL HAVE POPS ON THE LOW END... 20-30% ORIENTED NW TO SE RESPECTIVELY...SAT AFTERNOON/EVENING. THICKNESSES BOTH FRI AND SAT STAY SLIGHTLY BELOW NORMAL...WITH A BIT MORE SUNSHINE ANTICIPATED SAT THAN FRI... SO WILL HOLD ONTO HIGHS FROM THE MID 80S TO NEAR 90 WITH LOWS IN THE UPPER 60S TO LOWER 70S. FOR SUN-WED: DEEP LAYER WIND FIELDS REMAIN VERY WEAK SUNDAY WITH ONLY A SUBTLE SURFACE TROUGH EVIDENT THROUGH THE PIEDMONT... HOWEVER WE WILL START TO SEE PW VALUES RECOVER BACK UP ABOVE SEASONAL NORMALS... SUGGESTING A TREND BACK TO MORE SEASONALLY TYPICAL COVERAGE OF AFTERNOON PULSE CONVECTION FOR SUNDAY. AN ANOMALOUSLY STRONG MID LEVEL VORTEX (MID LEVEL HEIGHTS AS LOW S 2-3 STANDARD DEVIATIONS BELOW NORMAL) AS LOW AS WILL WOBBLE EASTWARD ACROSS SRN ONTARIO AND THE NRN GREAT LAKES SUN-TUE THEN INTO QUEBEC WED... AND THIS BROAD TROUGHING OVER ERN NOAM WILL MEAN INCREASINGLY UNSETTLED WEATHER FOR NC... WITH SW LOW LEVEL AHEAD OF THE SLOWLY APPROACHING SURFACE COLD FRONT... AND STRENGTHENING MID LEVEL WESTERLY FLOW FOSTERING BETTER STORM ORGANIZATION. WILL PLACE GOOD CHANCES OF SHOWERS AND STORMS FOCUSED ON EACH AFTERNOON/EVENING MON-TUE... WITH PERHAPS A SOUTHEASTWARD SHIFT OF THE HIGHER POPS WED TO LEVERAGE THE POSSIBILITY THAT THE SURFACE FRONT MIGHT DROP SE INTO THE CWA AND PUSH THE BETTER MOISTURE INTO SRN/ERN NC. SEE NOTHING TO INDICATE A MAJOR DEPARTURE FROM CLIMATOLOGICAL TEMPS... AS GREATER-THAN-USUAL CLOUD COVER WITH HEATING EACH DAY WILL MODULATE SLIGHTLY ABOVE- NORMAL THICKNESSES... SO WILL STICK WITH DAILY HIGHS IN THE UPPER 80S TO LOWER 90S... AND DAILY LOWS NEAR 70 TO THE LOWER 70S. -GIH && AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 105 AM THURSDAY... A MOIST AND UNSTABLE AIR MASS WILL SUPPORT THE DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVERNIGHT THROUGH THURSDAY NIGHT AS AN UPPER LEVEL TROUGH AND ATTENDANT SURFACE BOUNDARY MOVES ACROSS THE AREA. THE SHOWERS AND STORMS WILL BE MOST NUMEROUS DURING THE AFTERNOON AND EARLY EVENING HOURS. EXPECT MVFR/IFR VISIBILITIES AND CEILINGS IN VICINITY OF THE HEAVIER SHOWERS AND STORMS. AWAY FROM THE CONVECTION...EXPECT VFR CONDITIONS WITH SFC WINDS PREDOMINATELY WEST-SOUTHWEST AT LESS THAN 10 KTS. IMPROVING AVIATION CONDITIONS ANTICIPATED FRIDAY THROUGH SATURDAY AS A SLIGHTLY DRIER MORE STABLE AIR MASS COVERS MOST OF THE REGION. SCATTERED AFTERNOON-EARLY EVENING CONVECTION WILL STILL BE PROBABLE IN VICINITY OF KFAY AND KRWI FRIDAY WHERE AVAILABLE MOISTURE AND LOW LEVEL INSTABILITY WILL BE BEST COMPARED TO THE PIEDMONT. ANY CONVECTION SATURDAY IS EXPECTED TO BE ISOLATED. BY SUNDAY AND MONDAY ...REMNANTS OF DECAYING THUNDERSTORM COMPLEXES ORIGINATING IN THE MIDWEST MAY BEGIN TO AFFECT CENTRAL NC...LEADING TO A SLIGHTLY BETTER CHANCE FOR SCATTERED CONVECTION AND ASSOCIATED MVFR CONDITIONS. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS NEAR TERM...VINCENT SHORT TERM...NP LONG TERM...HARTFIELD AVIATION...WSS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
120 AM EDT THU JUL 10 2014 .SYNOPSIS... HIGH PRESSURE OVER THE UPPER MIDWEST WILL MOVE EAST ACROSS THE GREAT LAKES ON THURSDAY AND BE LOCATED NEAR NEW YORK CITY BY SATURDAY MORNING. A WARM FRONT WILL BE MOVING NORTHEAST FROM THE LOWER OHIO VALLEY ON SATURDAY AS A COLD FRONT DROPS ACROSS THE WESTERN GREAT LAKES. THE TWO FRONTS WILL CONVERGE ON THE AREA ON SUNDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... SOME SHOWERS DEVELOPING ON THE LAKE. UPDATED THE GRIDS TO REFLECT THIS. SOME THUNDER IS ALSO POSSIBLE. AT THIS TIME EXPECTING IT TO STAY OVER THE WATER...THIS WILL HAVE TO BE WATCHED. COLD FRONT CONTINUING TO SAG SOUTH OF THE AREA THIS EVENING. SHOWERS ON THE DECREASE. SOME TROFINESS AND RIGHT REAR QUAD OF THE JET MAY KEEP SOME ISOLATED SHOWERS GOING TO AROUND MIDNIGHT MAINLY OVER THE SOUTHERN PORTION OF THE FORECAST AREA. SKIES WILL BE MOSTLY CLEAR TO PARTLY CLOUDY OVERNIGHT. THE MODELS HAVE PLENTY OF LOW LEVEL MOISTURE AROUND AND WITH THE UPPER TROF ACROSS THE AREA SOME CLOUDINESS WILL LINGER. THE HRRR MODEL TRIES TO DEVELOP SOME SHOWERS OVER THE LAKE TOWARD DAYBREAK. THIS MAY OCCUR BECAUSE OF THE WARM LAKE AND SOME CONVERGENCE. MADE ONLY MINOR ADJUSTMENTS TO THE LOWS. IF THE CLOUDS STAY PATCHY TEMPERATURES SHOULD CONTINUE TO DROP WITH THE LIGHT WINDS. && .SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/... SOME OF THE MODELS SHOW ONE LAST SHORT WAVE SLIDING THROUGH THE TROUGH ON THURSDAY MORNING. I SUPPOSE A SHOWER COULD SNEAK OFF THE LAKE ACROSS EXTREME NE OH/NW PA IN THE MORNING OR MIDDAY OTHERWISE THE DRY AIR AND SUBSIDENCE SHOULD WIN OUT. HIGHS IN THE 70S AGAIN. SUNNY FRIDAY WITH PERHAPS A FEW HIGH CLOUDS AND PERHAPS A FEW CUMULUS ACROSS NE OH/NW PA. HIGHS GENERALLY MID 70S TO LOWER 80S. MOST OF THE MODELS ARE HOLDING OFF ON THE SHOWERS FOR SATURDAY WHICH SEEMS REASONABLE AS THE SURFACE HIGH WILL JUST BE TO THE EAST AND THERE SHOULD BE PLENTY OF DRY AIR IN THE LOWER LAYERS. CANNOT RULE OUT A WARM ADVECTION SHOWER GETTING INTO NW OHIO. DEWPOINTS WILL START TO INCREASE BUT WILL LIKELY NOT GET INTO THE UNCOMFORTABLE RANGE YET. TEMPS SHOULD RECOVER TO NEAR NORMAL. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... MOST OF THE MODELS SHOW A SWATCH OF SHOWERS AND THUNDERSTORMS SPILLING ACROSS THE LOWER GREAT LAKES SATURDAY NIGHT AND ESPECIALLY ON SUNDAY AS A WARM FRONT PUSHES NORTH AND A COLD FRONT SAGS SOUTHEAST ACROSS THE GREAT LAKES. WE MAY NEED TO GO WITH HIGHER POPS BUT STILL NOT OVERLY CONFIDENT ABOUT THE TIMING. IF THERE IS A THUNDERSTORM COMPLEX AND IT MISSES THE AREA OR MOVES ACROSS THE AREA VERY QUICKLY THEN WE END UP WITH JUST A FEW SHOWERS. WILL JUST KEEP IT A CHANCE FOR NOW. SHOULD BE MORE HUMID BY SUNDAY BUT TEMPS ARE A LITTLE TRICKY DEPENDING ON THE AMOUNT OF CLOUDS AND SHOWERS. WILL SPLIT THE DIFFERENCE AND GO FOR HIGHS AROUND 80. COULD REACH THE LOWER/MID 80S WITH SOME SUNSHINE AND IT COULD STAY IN THE 70S WITH ENOUGH CLOUDS AND SHOWERS. UNSEASONABLY COOL AIR MASS FOR EARLY NEXT WEEK AS A PROMINENT TROUGH REMAINS NEARLY STATIONARY ACROSS THE GREAT LAKES. COLD FRONT COMES ACROSS MONDAY WITH SHOWERS/THUNDERSTORMS. THERE MAY BE SHOWERS THAT POP UP WITH SECONDARY TROUGHS TUESDAY AND WEDNESDAY...BUT QUESTION WILL BE HOW MUCH MOISTURE WILL BE AROUND. IF H8 TEMPS GET BELOW 8C OR SO AND WINDS SHIFT OUT OF THE NORTHWEST THE LAKE MAY HELP WITH THAT MOISTURE. TEMPERATURES WILL BE BELOW NORMAL AND BY MID WEEK TEMPS WILL BE ON EITHER SIDE OF 70 FOR HIGHS. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... THE SHOWERS OVER WESTERN LAKE ERIE CONTINUE TO SLOWLY DIMINISH AND EXPECT DRY WEATHER AT ALL OF THE TAFS. SOME PATCHES OF MID LEVEL CLOUDS WILL AFFECT KCLE AND KERI OVERNIGHT. ALSO EXPECTING SOME FAIR WEATHER CUMULUS DURING THE DAY. A FEW HOURS OF BKN CIGS ARE POSSIBLE ACROSS NE OH AND NW PA AROUND MIDDAY. LIGHT AND VARIABLE FLOW WILL BECOME N TO NE AFTER DAYBREAK. SPEEDS WILL BE UNDER 10 KNOTS THE ENTIRE PERIOD. OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY IN THUNDERSTORMS. && .MARINE... ONE LAST TROUGH TO CROSS THE LAKE EARLY THIS EVENING THEN HIGH PRESSURE MOVES OVERHEAD FOR THURSDAY. SO LIGHT WEST-NORTHWEST WINDS WILL BECOME LIGHT/VARIABLE TONIGHT. THE HIGH SHIFTS EAST FRIDAY AND A LIGHT SOUTHERLY FLOW RESULTS. SHOWERS/THUNDERSTORMS ENTER THE FORECAST SATURDAY NIGHT AND SUNDAY AS THE ATMOSPHERE BECOMES MORE UNSTABLE AHEAD OF THE NEXT SYSTEM. THE COLD FRONT WILL CROSS THE LAKE ON MONDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KOSARIK NEAR TERM...KIELTYKA SHORT TERM...KOSARIK LONG TERM...KOSARIK/OUDEMAN AVIATION...KUBINA MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS TULSA OK
1148 PM CDT WED JUL 9 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. SHOWERS AND THUNDERSTORMS ACROSS KS CONTINUE TO DROP SOUTHEAST LATE THIS EVENING. THIS ACTIVITY SHOULD BEGIN TO IMPACT THE KBVO/KTUL AND KRVS TAF SITES AROUND 09-11Z AND THE REMAINDER OF THE TAF SITES AFTER 14Z. BRIEF MVFR CIGS/VSBYS WILL BE POSSIBLE IN THE STORMS. && .PREV DISCUSSION... /ISSUED 952 PM CDT WED JUL 9 2014/ DISCUSSION... DIFFUSE FRONTAL ZONE EXTENDING FROM ARKLATEX NORTHWEST INTO SW KANSAS THIS EVENING IS EXPECTED TO GRADUALLY LIFT NORTH OVERNIGHT. 00Z NAM SHOWS BOUNDARY AT 8590MB FROM ABOUT FSM-ICT BY 12Z THURSDAY. CLUSTERS OF STORMS CONTINUE TO ORGANIZE ACROSS NEBRASKA AND NORTHERN KANSAS THIS EVENING AND SHOULD CONTINUE GROWING UPSCALE AS LOW LEVEL WARM ADVECTION STRENGTHENS. GOOD CHANCE THAT AN ORGANIZED COMPLEX OF STORMS WILL DEVELOP THERE AND MOVE SE OVERNIGHT LIKELY REACHING PARTS OF NE OKLAHOMA BEFORE 12Z. EXISTING FORECAST POP CONFIGURATION BASICALLY GOOD...BUT HAVE RAISED TO LIKELY IN AREAS NW OF TULSA AFTER 09Z AS HRRR HAS REMAINED VERY CONSISTENT IN BRINGING COMPLEX TO THESE AREAS 09-12Z. ALSO BUMPED POPS UP SOME FOR 12-18Z THURSDAY NORTH OF I-40. SEVERE THREAT WILL BE DEPENDENT ON HOW ORGANIZED COLD POOL CAN BECOME...AT THIS TIME IT STILL LOOKS LIMITED. UPDATED PRODUCTS WILL BE OUT SHORTLY. PREV DISCUSSION... /ISSUED 628 PM CDT WED JUL 9 2014/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR CONDITIONS EXPECTED THIS EVENING AND THROUGH MOST OF THE NIGHT. THUNDERSTORMS SHOULD DEVELOP ACROSS KS TONIGHT EVENTUALLY IMPACTING ALL TAF SITES AROUND 10-12Z. BRIEF MVFR CIGS/VSBYS POSSIBLE IN AND NEAR STORMS. PREV DISCUSSION... /ISSUED 341 PM CDT WED JUL 9 2014/ DISCUSSION... WEAKENING FRONTAL ZONE REMAINS ALONG THE RED RIVER AND WILL BEGIN ITS NORTHEASTWARD MOVEMENT TONIGHT THROUGH THURSDAY. THE MOST LIKELY SCENARIO FOR OVERNIGHT STORMS IS AN EXPANDING COMPLEX TO DEVELOP ACROSS THE HIGH PLAINS...AND TRACK SOUTHEASTWARD INTO THE AREA. HIGHEST PRECIP CHANCES WILL BE FOCUSED ACROSS NORTHERN AND EASTERN PORTIONS OF THE FORECAST AREA ACCORDINGLY. THE RETURN TO HOT AND HUMID CONDITIONS WILL BEGIN ON FRIDAY WITH TEMPERATURES PEAKING SATURDAY INTO SUNDAY. A FEW STORMS MAY DEVELOP IN THE HIGHER TERRAIN EACH DAY HOWEVER CHANCES WILL REMAIN VERY LOW. AN INITIAL WIND SHIFT BEING AN INITIAL FRONTAL BOUNDARY AND/OR CONVECTIVE OUTFLOW WILL MAKE A PUSH INTO NORTHEAST OKLAHOMA ON SUNDAY. THIS RAISES UNCERTAINTIES ON TEMPS IN THIS ZONE...WHILE HOT TEMPS PREVAIL FURTHER SOUTH ACROSS MUCH OF THE FORECAST AREA. THIS BOUNDARY WILL SLOWLY WORK SOUTHWARD SUNDAY NIGHT THROUGH MONDAY...BEFORE A STRONGER SURGE OF COOLER AND DRIER AIR ARRIVES FOR TUESDAY THROUGH MID NEXT WEEK. THE BOUNDARY WILL ALSO MARK A ZONE OF INCREASED PRECIPITATION CHANCES. THE TEMPERATURES FOR MID TO LATE NEXT WEEK CONTINUE TO BE SHOWN ABNORMALLY COOL FOR THIS TIME OF THE YEAR...AND SHOULD THIS VERIFY IT WILL BE A MARKED CHANGE FROM THE UPCOMING WEEKEND TEMPS. && .PRELIMINARY POINT TEMPS/POPS... TUL 69 91 75 97 / 40 50 0 0 FSM 70 91 73 94 / 10 40 0 0 MLC 73 92 74 94 / 20 10 0 0 BVO 65 87 72 97 / 50 50 0 0 FYV 63 87 70 89 / 10 40 10 10 BYV 63 86 69 89 / 10 30 10 10 MKO 69 91 73 94 / 20 40 0 0 MIO 65 88 71 92 / 20 50 10 0 F10 71 91 73 94 / 20 30 0 0 HHW 72 94 73 95 / 20 10 0 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...99 LONG TERM....99 AVIATION...18
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
525 AM EDT THU JUL 10 2014 .SYNOPSIS... A PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN AS IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE SURFACE...THE AREA WILL REMAIN VULNERABLE TO ISOLATED SHOWERS AND THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A SERIES OF REINFORCING COLD FRONTS WILL PROVIDE SEVERAL OPPORTUNITIES FOR RAINFALL THROUGH EARLY NEXT WEEK...WHILE HELPING TO CARVE OUT A HIGHLY ANOMALOUS UPPER TROUGH AND BONAFIDE POLAR VORTEX ACROSS SOUTHEASTERN CANADA AND THE UPPER GREAT LAKES. && .NEAR TERM /THROUGH TONIGHT/... DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE. ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS ARE ACROSS THE NW MTNS. ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA. HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS THE LOWER SUSQ VALLEY. A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER SUSQ VALLEY. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2 WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH. EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE DELMARVA NEAR Q-STNRY FRONT AND HI MSTR PWS AXIS. STILL CANT RULE OUT AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA BUT POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE A LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT LKS/OH VLY WILL LKLY BRING SOME MID-HIGH CLOUDS INTO WRN SXNS BY 12Z SAT. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY DRY. STALLED FRONT ALONG THE SOUTHEAST COAST SHOULD PIVOT BACK NWD AS WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT LKS-MIDWEST. AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON. ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF STRONGER WINDS/CYC FLOW ALOFT AND SEVERAL REINFORCING COLD FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR SHOWERS/TSTMS THROUGH AT LEAST TUESDAY. THE HIGHLY ANOMALOUS AMPLIFICATION OF THE LARGE SCALE PATTERN IS A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS. THIS WELL- ADVERTISED HIGH MERIDIONAL EVENT WILL FEATURE A FULL-LATITUDE RIDGE AND SEARING HEAT OUT WEST...NOT BE BE OUTDONE BY THE RETURN OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH 500MB STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS VERY HIGH FROM TUE-THU OF NEXT WEEK. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... 11-3.9UM SATL IMAGERY SHOWING EXTENSIVE VALLEY FOG ACROSS THE NORTHERN MTNS EARLY THIS MORNING. A COMBINATION OF 09Z SFC OBS...CONDITIONAL CLIMATOLOGY AND LATEST RAP OUTPUT SUGGEST KBFD...KIPT AND KUNV WILL EXPERIENCE SOME IFR CONDS IN THE 09Z-11Z TIME FRAME. ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT BY 12Z...WITH PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY. HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC MTNS...INCLUDING KJST AND KAOO. OUTLOOK... FRI-SAT...PATCHY AM FOG POSSIBLE. SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...FITZGERALD SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
502 AM EDT THU JUL 10 2014 .SYNOPSIS... PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN AS IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE SURFACE...THE AREA WILL REMAIN VULNERABLE TO MAINLY ISOLATED SHOWERS AND THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A SERIES OF REINFORCING FRONTS PROVIDE SEVERAL OPPORTUNITIES FOR RAIN THE MIDDLE OF NEXT WEEK...WHILE HELPING TO CARVE OUT A BONAFIDE POLAR VORTEX OVER SOUTHEASTERN CANADA AND THE UPPER GREAT LAKES. && .NEAR TERM /THROUGH TONIGHT/... DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE. ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS ARE ACROSS THE NW MTNS. ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA. HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS THE LOWER SUSQ VALLEY. A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER SUSQ VALLEY. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2 WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH. EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE DELMARVA NEAR Q-STNRY FRONT AND HI MSTR AXIS. STILL CANT RULE OUT AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA BUT POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE A LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT LKS/OH VLY SHOULD BRING SOME CLOUDS INTO WRN SXNS BY 12Z SAT. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY DRY. STALLED FRONT ALONG THE EAST COAST SHOULD PIVOT BACK NWD AS WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT LKS-MIDWEST. AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON. ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF STRONGER WINDS ALOFT AND SEVERAL REINFORCING COLD FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR SHOWERS/TSTMS THROUGH AT LEAST TUESDAY. A HIGHLY ANOMALOUS AMPLIFICATION OF THE UPPER PATTERN IS A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS...FEATURING A FULL- LATITUDE RIDGE AND SEARING HEAT OUT WEST NOT BE BE OUTDONE BY THE RETURN OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS QUITE HIGH FROM TUE-THU OF NEXT WEEK. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... 11-3.9UM SATL IMAGERY SHOWING EXTENSIVE VALLEY FOG ACROSS THE NORTHERN MTNS EARLY THIS MORNING. A COMBINATION OF 09Z SFC OBS...CONDITIONAL CLIMATOLOGY AND LATEST RAP OUTPUT SUGGEST KBFD...KIPT AND KUNV WILL EXPERIENCE SOME IFR CONDS IN THE 09Z-11Z TIME FRAME. ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT BY 12Z...WITH PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY. HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC MTNS...INCLUDING KJST AND KAOO. OUTLOOK... FRI-SAT...PATCHY AM FOG POSSIBLE. SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...FITZGERALD SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
430 AM EDT THU JUL 10 2014 .SYNOPSIS... PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN AS IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE SURFACE...THE AREA WILL REMAIN VULNERABLE TO MAINLY ISOLATED SHOWERS AND THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A SERIES OF REINFORCING FRONTS PROVIDE SEVERAL OPPORTUNITIES FOR RAIN THE MIDDLE OF NEXT WEEK...WHILE HELPING TO CARVE OUT A BONAFIDE POLAR VORTEX OVER SOUTHEASTERN CANADA AND THE UPPER GREAT LAKES. && .NEAR TERM /THROUGH TONIGHT/... DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE. ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS ARE ACROSS THE NW MTNS. ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA. HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS THE LOWER SUSQ VALLEY. A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER SUSQ VALLEY. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2 WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH. EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE DELMARVA NEAR Q-STNRY FRONT AND HI MSTR AXIS. STILL CANT RULE OUT AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA BUT POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE A LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT LKS/OH VLY SHOULD BRING SOME CLOUDS INTO WRN SXNS BY 12Z SAT. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY DRY. STALLED FRONT ALONG THE EAST COAST SHOULD PIVOT BACK NWD AS WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT LKS-MIDWEST. AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON. ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF STRONGER WINDS ALOFT AND SEVERAL REINFORCING COLD FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR SHOWERS/TSTMS THROUGH AT LEAST TUESDAY. A HIGHLY ANOMALOUS AMPLIFICATION OF THE UPPER PATTERN IS A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS...FEATURING A FULL- LATITUDE RIDGE AND SEARING HEAT OUT WEST NOT BE BE OUTDONE BY THE RETURN OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS QUITE HIGH FROM TUE-THU OF NEXT WEEK. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... CENTRAL PA REMAINS IN A REGION OF RELATIVELY HIGH LOW-LVL MOISTURE TODAY...EVEN THOUGH STALLED COLD FRONT IS NOW EAST OF THE AREA. THE MAIN AVIATION CONCERN THIS MORNING WILL BE THE POSSIBILITY OF PATCHY FOG/LOW CIGS DUE TO RADIATIONAL COOLING. A COMBINATION OF 05Z DWPT DEPRESSIONS...CONDITIONAL CLIMATOLOGY AND LATEST RAP OUTPUT SUGGEST KBFD AND KIPT ARE MOST SUSCEPTIBLE TO A PERIOD OF IFR CONDS EARLY THIS MORNING. KIPT ALREADY HAS A 500FT CIG AT 05Z...BUT ARRIVAL OF MID LVL CLOUDS MAY BRIEFLY IMPROVE CONDS BTWN 06Z-08Z. ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT BY 12Z...WITH PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY. HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC MTNS...INCLUDING KJST AND KAOO. OUTLOOK... FRI-SAT...PATCHY AM FOG POSSIBLE. SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...FITZGERALD/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
204 AM EDT THU JUL 10 2014 .SYNOPSIS... A FRONTAL BOUNDARY WILL PUSH THROUGH THE AREA TONIGHT AND REMAINS IN PLACE THURSDAY BEFORE WASHING OUT BY FRIDAY. WEAK HIGH PRESSURE WILL RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE AREA EARLY NEXT WEEK. && .NEAR TERM /THROUGH TODAY/... AS OF 2 AM...REMNANT SHOWER AREA ASSOCIATED WITH EARLIER CONVECTIVE COMPLEX IS BEGINNING TO LIFT AWAY FROM THE I-40 CORRIDOR...WHILE ADDITIONAL SHOWER ACTIVITY WAS APPROACHING THE UPPER SAVANNAH RIVER VALLEY. EVEN THIS WAS BEGINNING TO SHOW SIGNS OF STRUGGLING AGAINST THE INCREASINGLY STABLE AIR MASS OVER THE AREA. POPS HAVE BEEN INCREASED FOR THE NEXT FEW HOURS TO ACCOUNT FOR THESE TWO AREAS OF CONVECTION...BUT FEEL THAT WE SHOULD BE FREE OF ALL BUT A COUPLE OF STRAY SHOWERS BY DAYBREAK. AS OF 915 PM...A BAND OF SHOWERS AND THUNDERSTORMS WAS DRIFTING EAST ACROSS THE NC MTNS. LATEST MESOSCALE ANALYSIS INDICATED THAT CAPE VALUES ALONG AND AHEAD OF THE CONVECTION RANGED FROM 500-1000 J/KG WITH LITTLE TO NO CIN. HOWEVER...CIN IS ANTICIPATED TO INCREASE ACROSS THE REGION OVER THE NEXT TWO HOURS. I WILL UPDATE THE FORECAST TO ACCOUNT FOR THE RECENT COVERAGE AND TIME THE PLACEMENT AND DECREASING COVERAGE FOR THE REST OF THIS EVENING. AS OF 745 PM...WIDELY SCATTERED SHRA/TSRA REMAINED ACROSS THE FORECAST AREA. I WILL UPDATE THE FORECAST TO LOWER POPS ACROSS THE I-77 CORRIDOR...KEEP CHC POPS ELSEWHERE. I WILL ALSO INCREASE THE MENTION OF FOG ACROSS THE REGION LATE TONIGHT. AS OF 530 PM...A LARGE CLUSTER OF THUNDERSTORMS WAS PUSHING ACROSS THE I-77 CORRIDOR. I WILL UPDATE THE FORECAST TO INCREASE POPS OVER THE NEXT TWO HOURS ACROSS THE CLT METRO AREA. OUTFLOW GOVERNED TEMPERATURES WILL REMAIN CHALLENGING THROUGH THE EVENING...I WILL UPDATE WITH OBS. AT 215PM...MOST THUNDERSTORM COVERAGE AT MID AFTERNOON IS ACROSS THE SOUTHERN UPSTATE EASTWARD INTO NC. NUMEROUS STORMS DEVELOPED IN A DIFFERENTIAL HEATING AXIS CREATED BY CLOUD COVER TO NORTH EARLIER TODAY. PLUS THE LEE TROF HAS PROVIDED SOME LOW LEVEL CONVERGENCE. AN UPPER SHORT WAVE DEPICTED BY THE RAP IS ALSO CROSSING THE AREA. SHOULD SEE SOME ADDITIONAL DEVELOPMENT ACROSS THE NC MOUNTAINS/FOOTHILLS PER CAMS SO WILL CONTINUE WITH SCT TYPE POPS THOSE AREAS. SHOULD SEE THE COVERAGE OF CONVECTION WANE THIS EVENING AS S/W MOVES TO THE E. HOWEVER...A COLD FRONT JUST WEST OF THE APPALACHIANS IS FORECAST TO MOVE INTO THE NC MOUNTAINS THIS EVENING WHICH COULD KICK OFF SOME ADDITIONAL SHOWERS/THUNDERSTORMS...SO WILL SHOW AN UPTICK IN POPS OVER THE WEST THIS EVENING AGAIN. THE 12Z GFS SEEMS TO HAVE SOME CONVECTIVE FEEDBACK OVER FAR WESTERN NC IN THE 00Z-06Z TIME FRAME AND WILL NOT BUY INTO THE HIGH GFS QPF DEPICTED THERE. ON THU...THE FRONT IS FORECAST TO REACH THE PIEDMONT. THE MODELS DEPICT A WEAK WAVE DEVELOPING ON THE BOUNDARY WHICH SHOULD TEND TO ENHANCE THE COVERAGE NEAR IT. PLUS...ANOTHER WEAK SHORT WAVE IS FORECAST TO CROSS THE AREA. HENCE...WILL STAY WITH THE IDEA OF SCT-NUMEROUS SHOWERS/STORMS ACROSS THE PIEDMONT DURING THE AFTERNOON...WITH LOWER POPS TO THE NORTH. SOUNDINGS LOOK MORE SATURATED WITH LESS DCAPE...SO DO NOT EXPECT MUCH IN THE WAY OF A SEVERE THREAT. MAX TEMPS ARE FORECAST TO BE ABOUT A CATEGORY BELOW CLIMO. && .SHORT TERM /TONIGHT THROUGH SATURDAY/... AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...STRETCHING NORTHEASTWARD INTO CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE ONGOING AS HEATING WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO THE SURFACE BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID CONVECTION. MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE LIFTING TO THE NORTHEAST ALLOWING H5 HEIGHTS TO RISE. POPS WILL TAPER DOWN DUE TO RISING HEIGHTS ALOFT AND HEATING LOSS INTO THE OVERNIGHT HOURS OF FRIDAY MORNING. LATEST GUIDANCE INDICATES POTENTIAL WEAK MESOLOW DEVELOPMENT ALONG THE FL PANHANDLE ON FRIDAY MORNING ALLOWING FOR ENHANCED SOUTHEASTERLY FLOW INTO THE CAROLINAS. THIS COMBINED WITH FLOW AROUND THE WESTERN ATLANTIC SURFACE RIDGE WILL ALLOW THE STALLED FRONTAL BOUNDARY TO GRADUALLY LIFT NORTHWARD TOWARDS THE CWFA INTO THE LATE AFTERNOON HOURS. MOISTURE CONVERGENCE ALONG THIS BOUNDARY WILL PROVIDE A FOCUS FOR CONVECTION ACROSS THE NC/SC PIEDMONT WHERE STEEPENING LAPSE RATES AND INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG. THUS WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND ALSO ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE FORECAST AREA BEFORE DIURNAL COOLING WARRANTS TAPERED POPS ACROSS THE ENTIRE REGION FOR THE OVERNIGHT. SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 245 PM EDT TUE...THE LATEST GLOBAL MODELS CONTINUE TO INDICATE THAT UPPER H5 HEIGHTS WILL FALL ACROSS THE SOUTHEAST SAT NIGHT INTO SUN AS AN UPPER RIDGE OF HIGH AMPLIFIES OVER THE WESTERN CONUS WHILE AN UPPER LOW PRESSURE TROUGH APPROACHES THE GREAT LAKES REGION FROM SOUTH CENTRAL CANADA. THIS TROUGH IS EXPECTED TO SWING ACROSS THE EASTERN STATES MON THROUGH WED. AT THE SURFACE...BERMUDA HIGH WILL PERSIST THROUGH SUN BEFORE SHIFTING TO THE EAST BY EARLY MON AS A COLD FRONT APPROACHES FROM THE NW. THE FRONT IS EXPECTED TO CROSS THE AREA THROUGH MON NIGHT FOLLOWED BY ANOTHER FRONT ON TUE. THE FRONT WILL REMAIN SOUTH OF THE AREA WED AS A CONTINENTAL HIGH BUILDS IN FROM THE NW. AS FOR OUR SENSIBLE WEATHER...POPS REMAIN NEAR CLIMO EACH DAY GIVEN LITTLE TO NO CAPPING ALOFT AND SEASONABLY UNSTABLE AIRMASS DURING THE PEAK HEATING HOURS. TEMPERATES WILL REMAIN NEAR...OR A FEW DEGREES BELOW NORMAL THROUGH THE PERIOD. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AT CLT...A COMPLEX OF SHOWERS IS LIFTING NORTH OF THE TERMINAL EARLY THIS MORNING...WHILE ADDITIONAL SCATTERED SHOWER ACTIVITY DEVELOPING 30 MILES OR SO SW OF THE AIRFIELD HAS STRUGGLED TO MAINTAIN ITSELF UNDER WANING INSTABILITY. WHILE I CAN/T RULE OUR A SHOWER PASSING NEAR THE TERMINAL FOR THE DURATION OF THE EARLY MORNING...FEEL THAT A VCSH MENTION SHOULD BE SUFFICIENT. OTHERWISE...A TYPICALLY COMPLEX JULY POST-CONVECTIVE FORECAST FOR THIS PERIOD...WITH A MYRIAD OF COMPETING ISSUES RE: THE FOG/LOW STRATUS POTENTIAL FOR LATER THIS MORNING. KCLT DID SEE SOME RAIN LAST EVENING...ALBEIT NOT VERY HEAVY RAIN. HOWEVER...MANY AREAS WITHIN 10 MILES OF THE TERMINAL SAW A VERY GOOD SOAKING...AND EXPECT PATCHES OF FOG AND/OR LOW STRATUS TO DEVELOP WITHIN THESE AREAS TOWARD DAYBREAK...WITH THE POTENTIAL FOR SOME IFR OR LOWER CIGS TO WAFT OVER KCLT. I THINK THIS IS ENOUGH OF A LOW PROBABILITY EVENT TO MAINTAIN A TEMPO FOR A SCT IFR DECK... ALONG WITH 3SM DURING THE PRE-DAWN HOURS. OTHERWISE...WITH WEAK COLD FRONT SETTLING INTO THE AREA...AND PLENTY OF MOISTURE LINGERING... EXPECT SCT TO NUMEROUS CONVECTIVE CELLS TO REDEVELOP THU AFTERNOON...WARRANTING A PROB30 MENTION BY EARLY AFTERNOON...AND CATEGORICAL TSRA BY MID-AFTERNOON OR SO. ELSEWHERE...THE MAIN CONCERN WILL BE THE FOG/LOW STRATUS POTENTIAL AT KAVL...WITH A BIT OF A LESSER CONCERN AT KHKY. KAVL HAS RECEIVED QUITE THE SOAKING IN THE PAST FEW HOURS...AND DESPITE THE EXTENSIVE MID/HIGH CLOUDS PERSISTING OVER THE AREA...IT SEEMS LIKELY THAT AS A RESULT OF THE WET GROUND...IFR OR SUB-IFR CONDITIONS WILL DEVELOP TOWARD DAYBREAK. KHKY HAS ALSO RECEIVED HEAVY RAINFALL RECENTLY...SO HAVE OPTED TO INCLUDE A TEMPO FOR 2SM THERE AS WELL. OTHERWISE...THE UPSTATE SC TERMINALS ARE EXPECTED TO REMAIN MVFR...EXCEPT FOR PERHAPS A BRIEF VISBY RESTRICTION AT KAND TOWARD DAYBREAK. OTHERWISE...WITH WEAK COLD FRONT SETTLING INTO THE AREA...AND PLENTY OF MOISTURE LINGERING... EXPECT SCT TO NUMEROUS CONVECTIVE CELLS TO REDEVELOP THU AFTERNOON...WARRANTING A PROB30/VCTS MENTION BY EARLY AFTERNOON...AND CATEGORICAL TSRA BY MID-AFTERNOON OR SO. OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE AREA. ANY RESTRICTIONS SHOULD MAINLY BE CONFINED TO DIURNAL TSTMS AND MORNING VALLEY FOG EACH DAY. CONFIDENCE TABLE... 06-12Z 12-18Z 18-24Z 00-06Z KCLT HIGH 91% HIGH 100% HIGH 98% HIGH 100% KGSP HIGH 95% HIGH 91% HIGH 100% HIGH 100% KAVL MED 75% MED 68% HIGH 100% HIGH 95% KHKY HIGH 91% HIGH 95% HIGH 100% HIGH 95% KGMU HIGH 95% HIGH 91% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 95% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...JDL/LG/NED SHORT TERM...WIMBERLEY LONG TERM...JOH/WIMBERLEY AVIATION...JDL
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
114 AM EDT THU JUL 10 2014 .SYNOPSIS... A SLOW MOVING COOL FRONT WILL SLIDE SOUTHEAST ACROSS THE REGION OVERNIGHT BEFORE STALLING ACROSS NORTHERN NORTH CAROLINA THURSDAY. WEAK AREAS OF LOW PRESSURE RIDING ALONG THE FRONT WILL KEEP UNSETTLED WEATHER GOING INTO LATE THURSDAY BEFORE WEAK HIGH PRESSURE SPILLS SOUTH INTO THE REGION FOR FRIDAY AND SATURDAY. DEEPER MOISTURE WILL RETURN LATER IN THE WEEKEND AND EARLY NEXT WEEK AHEAD OF A MUCH STRONGER COLD FRONT THAT WILL BE PASSING THROUGH THE REGION BY NEXT TUESDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 1250 AM EDT THURSDAY... SENT AN UPDATE TO RAISE POPS TO HIGH CHANCE/LIKELYS ACROSS THE SW AHEAD OF THE NEXT WAVE OF CONVECTION SEEN HEADING NE INTO NW NC. LATEST HRRR SPREADS THIS PRECIP NE INTO SOUTHERN VA AND PERHAPS EVEN OUT INTO THE PIEDMONT LATE PENDING HOW MUCH SURVIVES STABILITY OUT EAST. THUS ALSO INCLUDING CHANCE POPS SOUTHERN TIER DURING THE NEXT FEW HOURS MORE IN LINE WITH THE LATEST 4KM NAM. WILL KEEP SOME THUNDER MENTION AS WELL GIVEN LINGERING CAPE SEEN FEEDING INTO NW NC ATTM...BUT THINK SHOULD SEE DEEPER CONVECTION FADE IN THE NEXT COUPLE OF HOURS WITH MORE OF A HEAVY RAIN SCENARIO. AS OF 955 PM EDT WEDNESDAY... SHOWERS AND ISOLATED STORMS HAVE WEAKENED. STILL GOING TO SEE A THREAT ALONG A BOUNDARY STRETCHED FROM ERN KY SOUTHEAST TOWARD NC/VA OVERNIGHT. WILL KEEP THE ISOLATED/LOW CHANCE THREAT HERE WHILE HAVING IT MAINLY DRY ELSEWHERE. PATCHY FOG EXPECTED AS WELL WHERE SKIES CLEAR OUT SOME WHICH FAVORS THE NW CWA. NOT MUCH CHANGE TO THE OVERNIGHT FORECAST IN TERMS OF TEMPS. PREVIOUS VALID DISCUSSION... OVERNIGHT DRIER AIR AS SEEN ON THE WATER VAPOR LOOP WILL PUSH INTO THE REGION AS THE LEADING WEAK COLD FRONT DRIFTS SOUTH INTO NORTH CAROLINA AND STALLS. MODELS CONTINUED TO SHOW A LOW ALONG THE FRONT LATE TONIGHT THAT PUSHES THE DEEPER MOISTURE BACK INTO THE FORECAST AREA AFTER MIDNIGHT. HAVE A LULL IN THE PRECIPITATION... ESPECIALLY IN THE NORTHWEST HALF OF THE FORECAST AREA THIS EVENING...THEN BRING BETTER PROBABILITIES BACK IN BY MORNING. TEMPERATURES WILL DEPEND ON CLOUD COVER. WITH LITTLE DROP IN DEW POINTS TONIGHT MINIMUM TEMPERATURES WILL REMAIN MILD. IF CLEARING DOES OCCUR...MAY BE ADDING FOG BACK INTO THE FORECAST IN LOCATIONS THAT HAD RAIN THIS AFTERNOON. CLOUDS AND SHOWERS WILL ALSO LIMIT RISE IN TEMPERATURES...ESPECIALLY ACROSS THE SOUTH AND EAST ON THURSDAY. STAYED CLOSER TO COOLER SIDE OF GUIDANCE FOR MAXIMUM TEMPERATURES. && .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... AS OF 300 PM EDT WEDNESDAY... EXPECT AN AREA OF PRECIPITATION TO BE COVERING THE SOUTHEAST PORTION OF THE BLACKSBURG CWA AT THE START OF THE SHORT TERM PERIOD...WITH GOOD LOW LEVEL MOISTURE CONVERGENCE ALONG A SFC BOUNDARY IN THIS AREA. THIS REGION WILL ALSO FALL UNDER THE RIGHT REAR QUAD OF AN UPPER LEVEL AND GOOD UPPER LEVEL DIVERGENCE.THIS AREA OF PRECIP WILL GRADUALLY WANE DURING THE OVERNIGHT HOURS. FOR FRIDAY...THE UPPER LEVEL TROF AXIS WEAKENS AND SHIFTS SLIGHT EAST...PLACING THE BEST UPPER LEVEL SUPPORT EAST OF THE BLACKSBURG FORECAST AREA. STILL EXPECT WIDELY SCATTERED SHOWERS AND STORMS IN THIS AREA WITH WEAK CONVERGENCE ALONG THE DYING BOUNDARY. A SECOND AREA FOR PRECIP DEVELOPMENT WILL BE POSSIBLE IN THE MOUNTAINS...WITH AN UPSLOPE FLOW AND A SFC BOUNDARY FORECAST BY THE GFS/NAM/SREF/ECMWF NEAR THE VA/WV BORDER. AS THE DEEPEST MOISTURE AND BEST UPPER LEVEL SUPPORT SHIFT EAST...THE COVERAGE OF PRECIPITATION FRIDAY SHOULD BE LESS...AS WELL AS THE AMOUNT OF CLOUD COVER. GENERALLY FOLLOWED THE GFS MOS GUIDANCE FOR HIGHS WITH HAS PERFORMED THE BEST IN OUR AREA OVER THE PAST FEW DAYS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 245 PM EDT WEDNESDAY... AS SFC HIGH PRESSURE SHIFTS EAST ON SATURDAY...THE LOW LEVEL FLOW BECOMES EAST/SOUTHEAST BRINGING WEAK UPSLOPE FLOW. AT THIS POINT...THE DEEPEST MOISTURE WILL BE SOUTH AND EAST OF OUR AREA...BUT ENOUGH LOW LEVEL CONVERGENCE SHOULD SPARK ISOLATED/WIDELY SCATTERED SHOWERS/STORMS ACROSS THE SOUTHERN BLUE RIDGE. BY SUNDAY AND MONDAY...A LOW LEVEL THETA-E AXIS SURGES INTO OUR AREA WHICH WILL INCREASE COVERAGE OF DIURNALLY DRIVEN SHOWERS AND STORMS. BUT SIMILAR TO WHAT WE HAVE EXPERIENCED RECENTLY...A DEEP WEST/SOUTHWEST FLOW SHOULD KEEP THE CONVECTION SCATTERED. TOWARD THE END OF THE LONG TERM PERIOD THE MEDIUM RANGE MODELS CONTINUE TO FORECAST A BROAD UPPER TROF AND AN ASSOCIATED CUT OFF LOW OVER THE NORTHERN GREAT LAKES BY TUESDAY. THIS FEATURE HELPS DRIVE A COLD FRONT THROUGH OUR AREA ON TUESDAY. THERE ARE STILL DIFFERENCES WITH REGARD TO THE TIMING OF THIS FRONT...WITH THE 06Z GFS FASTER THAN THE 00Z ECMWF. USING A BLEND OF THESE SOLUTIONS...WILL CONTINUE TO CARRY A CHANCE OF SHOWERS/STORMS ON TUESDAY. TEMPERATURES SHOULD CLIMB IN ADVANCE OF THE FRONT TO NEAR OR SLIGHTLY ABOVE NORMAL...BEFORE FALLING BELOW NORMAL TUESDAY NIGHT INTO WEDNESDAY WHEN DRIER AIR ARRIVES. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 100 AM EDT THURSDAY... COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF. BATCH OF SHRA/TSRA HEADING NE INTO NW NC WILL BE THE MAIN CONCERN OVERNIGHT OUTSIDE OF DENSE FOG/STRATUS IN AREAS THAT SAW EARLIER HEAVY RAIN. EXPECT SOME OF THE SHOWERS TO THE SW TO LIKELY AFFECT KDAN AND PERHAPS AS FAR NORTH AS THE KBLF-KROA CORRIDOR THROUGH ABOUT 09Z/5AM...THEN NE TO AROUND KLYH BEFORE DAWN. THEREFORE HAVE INCLUDED A VCSH MENTION IN THESE SPOTS OR A FEW TEMPO HOURS FOR REDUCED VSBY IN BOTH SHRA/FOG OVERNIGHT. OTRW FOG SHOULD BECOME AN ISSUE AT TIMES OVERNIGHT ESPECIALLY WHERE IT RAINED...WHICH WILL BE ALL SITES. ATTM...THE FOG WILL ALSO BE DEPENDENT ON CLOUDS. THINK ENOUGH BREAKS TO ALLOW FOG FORMATION. WILL GO MAINLY MVFR/IFR LATE TONIGHT BUT NOT AS WIDESPREAD AS EARLIER GIVEN THICKER CLOUD CANOPY HEADING UP FROM THE SW. FOG WILL FADE BY MID MORNING EXCEPT IN AREAS OVER THE EAST THAT MIGHT STILL BE SEEING SOME SHRA BANDS LINGER. APPEARS CIGS WILL ALSO BE SLOWER TO LIFT GIVEN SO MUCH MOISTURE AROUND SO INCLUDED MORE LOW END VFR BASES AT MOST SPOTS DURING THE MORNING BEFORE BREAKING OUT TO A 4-5K CU FIELD AFTER MIDDAY. KDAN MAY BE THE EXCEPTION WHERE LOWER CIGS LINGER BEFORE MORE SHRA/TSRA DEVELOPS. MODELS KEEPING THE THREAT OF SHRA/TSRA AROUND OVER THE SOUTHEAST CWA THURSDAY...SO KEPT VCTS AT ROA/LYH/DAN...AND ADDED AT KBCB WITH A VCSH AT KBLF/KLWB PER SLOWNESS OF THE FRONT TO PUSH SE AND LINGERING LOW LEVEL MOISTURE WITH HEATING WHICH SHOULD BE BETTER OVER THE WEST/NW. OTRW EXPECT VFR OUTSIDE OF ANY STORMS FOR THE MOST PART. WAVE SHOULD FINALLY TAKE THE NEXT ROUND OF SHRA/TSRA TO THE SE THURSDAY EVENING WITH PERHAPS ENOUGH DRYING TO END CONVECTION AT ALL LOCATIONS AFTER MIDNIGHT. EXTENDED AVIATION... A LOWER PROBABILITY OF PRECIPITATION IS EXPECTED ACROSS THE AREA ON FRIDAY AND SATURDAY AS WEAK HIGH PRESSURE SLIDES IN FROM THE NORTH. MOISTURE AND MORE WIDESPREAD SHRA/TSRA LIKELY TO RETURN FOR THE END OF THE WEEKEND AS THE FRONT RETURNS NORTH RESULTING IN PERIODS OF MVFR CONDITIONS. OTRW PATCHY FOG RESULTING IN LOCAL MVFR TO IFR CONDITIONS LIKELY DURING THE LATE NIGHTS AND EARLY MORNINGS ESPCLY VALLEY LOCATIONS AND WHERE EARLIER AFTERNOON RAINFALL OCCURRED. && .EQUIPMENT... AS OF 100 AM EDT THURSDAY... COMMUNICATIONS OUTAGE CONTINUES WITH KDAN ASOS NOT TRANSMITTING. THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH NEAR TERM...AMS/JH/WP SHORT TERM...PH LONG TERM...AMS/PH/WERT AVIATION...AMS/JH/WP EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1140 AM EDT THU JUL 10 2014 .SYNOPSIS... A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY. A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE MID ATLANTIC REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... LATEST ANALYSIS SHOWING FRONTAL BOUNDARY STALLED OVER WRN PORTIONS OF THE CWA WITH AN AREA OF SHOWERS/EMBEDDED TSTMS DEVELOPING ALONG THE FRONT ACRS MECKLENBURG/LUNENBURG AS OF 11 AM. VERY MOIST AIRMASS IN PLACE ACRS THE REGION WITH PWAT VALUE OVER 2" ON 12Z WAL SOUNDING (AND 1.75-2" AT GSO). 12Z NAM BRINGS PRECIP FARTHER NORTH THAN PREVIOUS RUNS AND IT MAY BE ONTO SOMETHING AS IT IS VERIFYING WELL THUS FAR. HAVE THUS INCREASED POPS TO 70% OVER MUCH OF CENTRAL VA AS FAR N AS METRO RICHMOND THIS AFTN (WELCOME RAINFALL HERE). SATELLITE TRENDS SUGGEST LITTLE CLEARING THIS AFTN...WITH THE POSSIBLE EXCEPTION OF FAR SE VA/NE NC WHERE A BRIEF PERIOD OF PARTIAL CLEARING MAY OVERSPREAD THE REGION OVER THE NEXT FEW HRS BEFORE TSTMS REDEVELOP. MAIN CONCERN TODAY WILL BE FOR HEAVY RAIN AND POSSIBLE FLASH FLOODING. IR SATELLITE SHOWS DEEP MOISTURE PLUME FROM THE SW AND UPPER JET IS IN A FAVORABLE POSITION (RRQ FORCING) TO SUPPORT LIKELY POPS MOST AREAS THIS AFTN AND TONIGHT. IN ADDITION..SHOULD SEE TRAINING OF STORMS DUE TO LOW LEVEL SW JET BEING NEARLY PARALLEL AND SIMILAR IN MAGNITUDE TO THE FLOW ALOFT (LOW MBE VALUES). MUCH OF HAMPTON ROADS AND NE NC RECEIVED 2" OR MORE OF RAINFALL OVER THE PAST 24 HRS AND MAY NEED TO CONSIDER A FLASH FLOOD WATCH THIS AFTN THROUGH FRI MORNING IN THESE AREAS BUT CONFIDENCE TOO LOW IN PLACEMENT OF HEAVIEST PRECIP (ESPECIALLY GIVEN THE LATEST NAM KEEPING HEAVIER AMTS FARTHER INLAND/NW). WILL CONTINUE MENTION OF LCLLY HEAVY RAINFALL THREAT IN HWO. LOWERED MAX TEMPS A FEW DEGREES WITH HIGHS MAINLY IN THE LOWER-MID 80S. S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY ENHANCE CONVECTION CHCS OVERNIGHT BUT SHOULD KEEP THE THREAT OF PCPN GOING THROUGH THE NIGHT...PARTICULARLY ACRS SE VA/NE NC. POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES. LOWS M60S FAR NW TO LWR-MID 70S SE. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY EXITING OFF THE COAST DURING THE AFTN. DATA SHOWS PLENTY OF MSTR ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70. MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY SUNNY WITH HIGHS IN THE M-U80S. QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5 IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL APPALACHIANS. FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT. THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM 1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT). THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT. EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS BASED ON THE FRONT LIKELY STALLING OFFSHORE. TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER 80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S. OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID 70S NEAR THE COAST. && .AVIATION /15Z THURSDAY THROUGH MONDAY/... TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10 THOUSAND FEET. FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION LATE SUNDAY OR MONDAY. && .MARINE... SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN 2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED MORNING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB/MPR LONG TERM...SAM AVIATION...JAB MARINE...JAB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
650 AM EDT THU JUL 10 2014 .SYNOPSIS... A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY. A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE MID ATLANTIC REGION THIS WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST MSAS SHOWING FRONTAL BNDRY NOW STALLED ACROSS THE FA WITH A WEAK SFC TROF ALONG THE COAST. LATEST RADAR SHOWING SHWRS/TSTRMS CONTG TO DVLP ALONG THE COAST WITH SCNDRY BATCH OF LIGHTER PCPN APPRCHG WRN CNTYS FROM THE WEST. ADJUSTED MORNING GRIDS A BIT MORE TOWARD THESE CURRENT CNDTNS. PVS DSCN: MODELS AGREE THE FRONT STALLS ACROSS SERN PORTIONS OF FA LATER TODAY DUE TO A FLATTENING WSW FLOW ALOFT BCMG PARALLEL TO THE BOUNDARY. WHERE THE MODELS DIFFER IS WHAT THIS BOUNDARY DOES ONCE A WEAK S/W APPROACHES FROM THE SW BY THIS EVENING. NAM MOST AGGRESSIVE IN RETROGRADING THE BOUNDARY TO NEAR THE I95 CORRIDOR FOCUSING THE CONVECTION THERE. GFS/SREF HAVE IT MEANDERING AROUND THE COASTAL PLAIN AREAS...FOCUSING CONVECTION ACROSS SERN AREAS. TOSSED AROUND THE IDEA OF A FF WATCH FOR SERN VA/NE NC LATER TODAY AND TONIGHT GIVEN DUAL POLE ESTIMATES OF 2 TO 3.5 IN (WHICH HAS VERIFIED BY GROUND REPORTS) AND AN ADDITIONAL 1.5 TO 2.5 IN OF QPF. HOWEVER...MY CONFIDENCE LOWERED AFTER SEEING THE 00Z GUIDANCE WHERE THE NAM PUSHES AXIS OF HEAVIEST RAINFALL WEST OF WHERE ANY WATCH WOULD BE GIVEN THE RECENT RAINFALL AND WHERE IT HAS BEEN RATHER DRY OF LATE (I95 CORRIDOR) WHILE THE GFS ACTUALLY HAS THE HEAVIEST RAINFALL AFTER 00Z TONIGHT. DECIDED TO HOLD OFF AN ANY FF WATCH ATTM (FF GUID FOR THOSE AREAS AOA 2 IN PER HR)...BUT MENTIONED THE LCLLY HEAVY RAINFALL THREAT IN HWO. LEANED TOWARD A SREF TIMING SOLN WITH THIS PACKAGE WHICH SEEMS TO BE A COMPROMISE BTWN THE MODELS. GIVEN THE ABOVE SCENARIO...HAVE EXPANDED THE LIKELY POPS A BIT FURTHER NORTH THIS AFTRN BUT KEPT CHC POPS ACROSS NORTHERN HALF OF FA. ALSO KEPT THE CHC POPS ACROSS WRN HALF OF FA THIS MORNING GIVEN BATCH OF PCPN MOVG NE FROM WRN NC. HIGHS M-U80S. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY ENHANCE CONVECTION CHCS THIS EVENING BUT SHOULD KEEP THE THREAT OF PCPN GOING THROUGH THE NIGHT. HIGHEST POPS ACROSS SERN AREAS GIVEN A SREF SOLN. POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES. LOWS M60S-L70S. SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY EXITING OFF THE COAST DURING THE AFTRN. DATA SHOWS PLNTY OF MSTR ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70. MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY SUNNY WITH HIGHS IN THE M-U80S. QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5 IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL APPALACHIANS. FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT. THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM 1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT). THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT. EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS BASED ON THE FRONT LIKELY STALLING OFFSHORE. TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER 80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S. OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID 70S NEAR THE COAST. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10 THOUSAND FEET. FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION LATE SUNDAY OR MONDAY. && .MARINE... SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN 2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED MORNING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...MPR NEAR TERM...MPR SHORT TERM...MPR LONG TERM...SAM AVIATION...JAB MARINE...JAB
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1041 AM CDT THU JUL 10 2014 .UPDATE... ADJUSTED POPS AND HOURLY TEMPS REST OF TODAY. .SHORT TERM... SMALL MCS VORT CENTER CONTINUES TO MOVE SE AND PRODUCE SHRA/TSRA ACROSS SE 1/3 OF FORECAST AREA LATE THIS MORNING. IN ITS WAKE...SUN IS BREAKING OUT AND TEMPERATURES ARE BEGINNING TO RESPOND. WEAK SURFACE BOUNDARY APPEARS TO BE DROPPING THROUGH THE TENN VALLEY AND MID SOUTH REGIONS. BLENDED TOTAL PW CLEARLY SHOWS DEEP MOISTURE POOLING AHEAD OF THIS BOUNDARY IN A NW-SE ORIENTATION FROM CENTRAL OK ACROSS OUR AREA TOWARD FL PANHANDLE. WIDELY SCT SHRA/TSRA CONTINUE TO POP UP IN THIS MOIST/UNSTABLE AIRMASS BEHIND LEAD VORTICITY CENTER OVER SE MS. LARGER MCS CURRENTLY DROPPING SE ACROSS EASTERN OK AND FAR NW AR WILL CONTINUE TO PUSH SE TOWARD OUR AREA. HRRR SEEMS A BIT TOO SLOW WITH DROPPING THIS FEATURE SE...AND EXPECT THE COMINBATION OF HEATING...BOUNDARY AND APPROACH OF THIS SYSTEM WILL YIELD AN INCREASE IN COVERAGE OF SHRA/TSRA FROM THE NW LATER THIS AFTERNOON. ADDITIONALLY...DAYTIME HEATING AND RESIDUAL BOUNDARIES WILL ALLOW FORMATION OF AT LEAST WIDELY SCT SHRA/TSRA ELSEWHERE. HAVE ADJUSTED POPS TO ACCOUNT FOR TREND OF HIGHEST POPS IN SE REST OF THIS AM...AND THEN IN THE NW LATER TODAY. MAX TEMPS SEEM OK BASED ON CURRENT TRENDS...BUT ADJUSTED HOURLY TEMPS TO ACCOUNT FOR COOLER READINGS THIS MORNING DUE TO CLOUDS/PRECIP. /08/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 88 68 95 68 / 45 14 5 9 MERIDIAN 88 67 95 65 / 67 13 5 9 VICKSBURG 87 66 96 66 / 48 14 7 8 HATTIESBURG 86 70 96 70 / 68 21 19 7 NATCHEZ 86 69 95 70 / 46 18 17 6 GREENVILLE 89 69 96 70 / 53 5 2 8 GREENWOOD 89 67 94 66 / 47 5 2 9 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ AEG
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
825 AM CDT THU JUL 10 2014 .UPDATE...INCREASED POPS FOR THIS MORNING. .SHORT TERM...RADAR AND SATELLITE SHOW A SMALL MCS MOVING ACROSS CENTRAL AND SOUTHERN MS...WITH A FEW SHOWERS AND STORMS ALSO DEVELOPING OVER SE AR IN ASSOCIATION WITH ANOTHER WAVE DROPPING ESE ACROSS AR. GIVEN THIS...HAVE UPDATED FORECAST TO ADJUST TIMING OF PRECIPITATION TODAY TO MOVE AWAY FROM CONCEPT OF HIGHER POPS IN THE AFTERNOON. IN FACT...11Z HRRR SHOWS BULK OF PRECIPITATION OCCURRING THIS MORNING WITH LITTLE IN WAY OF REDEVELOPMENT DURING THE AFTERNOON. LOCAL WRF IS MORE BULLISH WITH AFTERNOON ACTIVITY IN SOUTHERN AREAS...BUT IT DOES NOT HAVE A GOOD HANDLE ON WHAT IS GOING ON NOW WHILE HRRR DOES. GIVEN SATELLITE SHOWING UPSTREAM ACTIVITY OVER AR/OK WILL NOT MESS WITH AFTERNOON FORECAST YET...BUT COULD LOOK AT ADJUSTING POPS FOR THE AFTERNOON DOWN IN SOME AREAS WITH A MIDDAY UPDATE. TEMPS COULD ALSO NEED TO BE ADJUSTED AT THAT TIME AS WELL...DEPENDING ON PRECIP COVERAGE THIS AM MAY BE TOO WARM IN CENTRAL/SOUTHERN AREAS. /08/ && .PREV DISCUSSION... /ISSUED 349 AM CDT THU JUL 10 2014/ SHORT TERM...TODAY THROUGH FRIDAY NIGHT... LATEST SATELLITE IMAGERY SHOWED AN UPPER TROUGH OVER THE MISSISSIPPI VALLEY WITH SOME WEAK UPPER DIVERGENCE. A WEAK SHORTWAVE ON THE BASE OF THE TROUGH WAS BRINGING IN SOME CONVECTION ACROSS THE REGION. THE WEAK SURFACE FRONTAL BOUNDARY CURRENTLY LOCATED TO THE NORTH OF THE AREA WILL DROP SOUTH INTO THE AREA THIS AFTERNOON. PWATS AROUND 2 INCHES WILL DECREASE FROM THE NORTH AS THE WEAK FRONT MOVES INTO THE REGION. PWATS WILL DECREASE TO AROUND 1-1.3 INCHES BEHIND THE BOUNDARY. A DRY SLOT OF LESS THAN ONE INCH WILL MOVE INTO THE REGION FRIDAY NIGHT. WITH LITTLE UPPER SUPPORT EXPECT THE WEAK SURFACE FRONTAL BOUNDARY TO STALL ACROSS AREA BY THIS EVENING. SO WILL KEEP CHANCES OF CONVECTION GOING THROUGH THIS EVENING UNTIL AFTER SUNSET. WITH MARGINAL INSTABILITY AND WEAK SHEAR UNDER DECENT CLOUD COVER EXPECT THESE STORMS TO REMAIN SUB-SEVERE...BUT A STRONG STORM OR TWO LOOK POSSIBLE THIS AFTERNOON AND EARLY EVENING WITH DAYTIME HEATING. THERE ALSO COULD BE SOME LOCALLY HEAVY DOWNPOURS WITH SOME LIMITED FLOODING POTENTIAL WITH THE LIGHT CORFIDI VECTORS. WITH LACK OF UPPER SUPPORT THE ACTIVITY SHOULD DIMINISH THIS EVENING. ON FRIDAY THE UPPER TROUGH WILL LIFT EAST OF THE REGION AS UPPER RIDGING BUILDS IN FROM THE WEST. THIS WILL PUSH THE SURFACE BOUNDARY AWAY FROM THE REGION. ON FRIDAY EXPECT DIURNAL CONVECTION TO BE AROUND WITH ISOLATED COVERAGE ACROSS THE SOUTH DURING THE AFTERNOON WHICH WILL DIMINISHING BY EVENING. WE SHOULD GET BETTER INSOLATION FOR WARMER TEMPS ON FRIDAY. AS FAR AS TEMPS ARE CONCERN WENT CLOSER TO NAM GUIDANCE FOR TODAY HIGHS IN THE MID TO UPPER 80S DUE TO CLOUD COVER. FOR FRIDAY WENT CLOSER TO THE WARMER GMOS GUIDANCE IN THE MID 90S. FOR NIGHTLY LOWS WENT CLOSER TO THE MILDER BLEND OF NAM/MAV GUIDANCE WITH LOWS IN THE MID 60S TO AROUND 70. AS FAR AS POPS MADE SOME ADJUSTMENTS TO MOS POPS WITH BETTER COVERAGE FOR TODAY. WENT CLOSE TO MOS POPS FOR TONIGHT AND FRIDAY./17/ LONG TERM...SATURDAY THROUGH THURSDAY...THE FIRST HALF OF THE EXTENDED WILL BE FAIRLY QUIET AS UPPER RIDGING WILL BE IN PLACE OVERHEAD. THIS WILL LEAD TO MOSTLY DRY CONDITIONS AND WARM TEMPERATURES. THERE COULD BE SOME CHANCE FOR AN ISOLATED STORM IN THE SOUTH THROUGH THE WEEKEND AS DAYTIME HEATING WILL COMBINE WITH ENOUGH INSTABILITY AND MOISTURE IN PLACE. THE GFS SHOWED SOME DRIER PW VALUES COMING THROUGH THE REGION WHICH WOULD PRECLUDE SHOWERS/STORMS FROM DEVELOPING. THE NAM AND ECMWF ON THE OTHER HAND CONTINUE TO SHOW PW VALUES AROUND 1.5 TO NEAR 2 INCHES THROUGH THE WEEKEND. THIS...ALONG WITH HIGHS REACHING INTO THE MID 90S...COULD SPARK SOME CONVECTION AND LEANED CLOSER TO THE NAM/ECMWF. HEADING INTO THE WEEK...THE UPPER RIDGING GIVES WAY TO A RATHER LARGE UPPER TROUGH THAT WILL BE LOCATED ACROSS THE GREAT LAKES REGION. THIS WILL TAKE UP RESIDENCE THROUGH THE REST OF THE PERIOD. A SERIES OF WAVES WILL MOVE THROUGH THE BASE OF THE TROUGH...ONE OF WHICH WILL SEND A COLD FRONT IN OUR DIRECTION. THIS FRONT WILL MOVE INTO THE ARKLAMISS TUESDAY INTO WEDNESDAY. BOTH THE GFS AND THE ECMWF BRING THE FRONT ALL THE WAY THROUGH THE CWA BY EARLY THURSDAY. GIVEN PLENTY OF MOISTURE AHEAD OF THE FRONT...WE WILL SEE A BETTER CHANCE FOR SHOWERS AND STORMS COME TUESDAY AND WEDNESDAY. BEHIND THE FRONT. ALSO BEHIND THE FRONT...SOME COOLER AIR WILL BE POSSIBLE WITH SOME BELOW NORMAL TEMPERATURES POSSIBLE. /28/ && .AVIATION... A FRONTAL BOUNDARY PUSHING SOUTH ACROSS THE AREA WILL BRING ADDITIONAL SHRA/TSRA ACTIVITY FOR TODAY UNTIL AROUND 01Z. OUTSIDE OF CONVECTION...MVFR CATEGORY FOG AND A FEW PATCHY AREAS OF LOW STRATUS WILL BE COMMON DURING THE EARLY MORNING HOURS. OTHERWISE...VFR CONDITIONS WILL PREVAIL OUTSIDE OF STORMS./17/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 88 68 95 68 / 55 14 5 9 MERIDIAN 88 67 95 65 / 56 13 5 9 VICKSBURG 87 66 96 66 / 50 14 7 8 HATTIESBURG 86 70 96 70 / 59 21 19 7 NATCHEZ 86 69 95 70 / 60 18 17 6 GREENVILLE 89 69 96 70 / 27 5 2 8 GREENWOOD 89 67 94 66 / 27 5 2 9 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ AEG
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
721 AM EDT THU JUL 10 2014 .SYNOPSIS... A PERSISTENT UPPER LEVEL TROUGH OVER THE GREAT LAKES WILL DAMPEN AS IT CROSSES THE NEW ENGLAND STATES INTO THE WEEKEND...WITH A WEAKENING QUASI-STATIONARY FRONT TRAILING SOUTHWARD ALONG THE MID ATLANTIC COAST. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE SURFACE...THE AREA WILL REMAIN VULNERABLE TO ISOLATED SHOWERS AND THUNDERSTORMS INTO THE FIRST PART OF THE WEEKEND. A SERIES OF REINFORCING COLD FRONTS WILL PROVIDE SEVERAL OPPORTUNITIES FOR RAINFALL THROUGH EARLY NEXT WEEK...WHILE HELPING TO CARVE OUT A HIGHLY ANOMALOUS UPPER TROUGH AND BONAFIDE POLAR VORTEX ACROSS SOUTHEASTERN CANADA AND THE UPPER GREAT LAKES. && .NEAR TERM /THROUGH TONIGHT/... DWINDLING SHRA CONTINUE TO RIDE ALONG DYING SECONDARY COLD FRONT ACROSS THE N MTNS EARLY THIS MORNING. LATEST RAP SUGGESTS THESE SHOWERS DISAPPEAR TOWARD DAWN...AS BLYR CONTINUES TO COOL/STABILIZE. ELSEWHERE...MCLEAR SKIES AND A LIGHT WIND HAVE RESULTED IN PATCHY FOG. 11-3.9U IMAGERY INDICATES THE MOST EXTENSIVE FOG/LOW CLOUDS ARE ACROSS THE NW MTNS. ANY FOG AND LOW CLOUDS WILL BURN OFF SHORTLY AFTER DAWN...GIVING WAY TO M/SUNNY START TO THE DAY OVER MOST OF CENTRAL PA. HOWEVER...AN UPPER LEVEL TROUGH MOVG EWD ACRS THE LOWER GRT LKS...COMBINED WITH WEAK INSTABILITY...SHOULD BE ENOUGH TO GENERATE SCT SHRA/TSRA DURING THE AFTN...MAINLY ACRS THE SCNTRL MTNS. 8H TEMPS BTWN 12-14C SHOULD TRANSLATE TO HIGHS FROM THE M70S OVR THE HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE M80S ACROSS THE LOWER SUSQ VALLEY. A SHOWER OR TWO MAY LINGER OVER THE SERN ZONES LATE THIS EVE...BUT HIGH PRES WILL DOMINATE FOR THE MOST PART WITH CLEARING AND PATCHY VALLEY FOG DEVELOPING OVERNIGHT AND INTO EARLY FRIDAY MORNING. GFS MOS APPEARS TOO COOL TONIGHT BASED ON BLEND OF ALL MDL SFC DWPTS. BCCONSALL APPEARS MUCH MORE REASONABLE...WITH LOWS RANGING FROM THE L50S OVR THE NW MTNS TO THE M60S OVR THE LOWER SUSQ VALLEY. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... VERY LITTLE CHANGE IN THE OVERALL PATTERN EXPECTED INTO DAY 2 WITH EVEN WEAKER FORCING ALOFT DUE TO DAMPENING OF UPPER TROUGH. EXPECT BULK OF PCPN TO REMAIN CONFINED TO ERN NC/VA TO THE DELMARVA NEAR Q-STNRY FRONT AND HI MSTR PWS AXIS. STILL CANT RULE OUT AN ISOLD SHRA/TSTM DURING THE AFTN OVER ERN PRTNS OF THE CWA BUT POPS WILL BE BARELY MENTIONABLE/AOB 20 PCT. TEMPS SHOULD EDGE A LITTLE WARMER THAN THURSDAY. STG WAA UPSTREAM OVER THE GRT LKS/OH VLY WILL LKLY BRING SOME MID-HIGH CLOUDS INTO WRN SXNS BY 12Z SAT. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE AREA SHOULD BE IN MORE OF A RETURN FLOW REGIME BY SAT AS THE SFC HIGH SLIPS OFF THE EAST COAST. SIMILAR TO DAYS 1 AND 2..STILL CANT RULE OUT AN ISOLD SHRA/TSTM IN SPOTS WHILE MOST AREAS STAY DRY. STALLED FRONT ALONG THE SOUTHEAST COAST SHOULD PIVOT BACK NWD AS WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT LKS-MIDWEST. AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON. ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF STRONGER WINDS/CYC FLOW ALOFT AND SEVERAL REINFORCING COLD FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR SHOWERS/TSTMS THROUGH AT LEAST TUESDAY. THE HIGHLY ANOMALOUS AMPLIFICATION OF THE LARGE SCALE PATTERN IS A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS. THIS WELL- ADVERTISED HIGH MERIDIONAL EVENT WILL FEATURE A FULL-LATITUDE RIDGE AND SEARING HEAT OUT WEST...NOT BE BE OUTDONE BY THE RETURN OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH 500MB STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS VERY HIGH FROM TUE-THU OF NEXT WEEK. && .AVIATION /11Z THURSDAY THROUGH MONDAY/... 11-3.9UM SATL IMAGERY SHOWING EXTENSIVE VALLEY FOG ACROSS THE NORTHERN MTNS EARLY THIS MORNING. HOWEVER...ANY LOW CIGS/FOG SHOULD RAPIDLY MIX OUT ARND 12Z...WITH PREDOMINATELY VFR CONDS EXPECTED FOR THE REST OF THE DAY. HOWEVER...A TROUGH OF LOW PRES APPROACHING FROM THE WEST WILL LIKELY TRIGGER SCT SHRA/TSRA DURING THE AFTN AND EVENING HRS. THE BEST CHANCE OF A BRIEF VIS REDUCTION WILL BE ACROSS THE SC MTNS...INCLUDING KJST AND KAOO. CLEARING SKIES AND A LIGHT WIND WILL PROMOTE PATCHY FOG TONIGHT...ESP WHERE RAIN FALLS LATER TODAY. OUTLOOK... FRI-SAT...PATCHY AM FOG POSSIBLE. SUN-MON...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...FITZGERALD SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
527 PM EDT THU JUL 10 2014 .SYNOPSIS... A STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE DELMARVA TONIGHT BEFORE SLOWLY PUSHING SOUTH OF THE AREA FRIDAY. HIGH PRESSURE BUILDS IN FROM THE NORTHEAST FRIDAY INTO SATURDAY. RETURN FLOW DEVELOPS LATE IN THE WEEKEND AND EARLY NEXT WEEK AS HIGH PRESSURE MOVES OFFSHORE AND AN STRONG UPPER LOW DIGS INTO THE UPPER MIDWEST. A COLD FRONT WILL APPROACH THE EASTERN SEABOARD TUESDAY BEFORE MOVING OFFSHORE BY WEDNESDAY. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... BACKDOOR COLD FRONT HAS CLEARED OUR CWA. BUT WITH TROFFING ALOFT, THERE IS STILL SUFFICIENT INSTABILITY FOR SHOWERS AND THUNDERSTORMS TO FORM. IF 7/8/14 WAS THE DAY THE HRRR AND COSPA RAN TO THEIR AGENT AND RENEGOTIATE THEIR CONTRACTS, TODAY IS THE DAY TO BE THANKFUL THE REVERSE CANT BE DONE. DIFFICULT MORE SUBTLE SCENARIO WITH NONE OF THE MESOSCALE MODELS HANDLING/VERIFYING CONVECTION WELL AND FALLING OFF TRACK RATHER QUICKLY WITHIN OUR CWA. WITH SHORT WAVES STILL PROGGED TO PROGRESS THROUGH THE TROF, SFC BASED INSTABILITY EXCEEDING 2K JOULES WEST, BOUNDARIES PROVIDING LIFT, WE ARE GOING TO KEEP THE PRESENT FORECAST, WATCH, GOING UNTIL WE SEE WHAT COMES OF THE CONVECTION EXITING THE ALLEGHENIES. ANY ESTF UPDATES ARE GOING TO BE BASED ON ADJUSTING FOR TEMPS WHERE PCPN IS OR JUST RECENTLY HAS OCCURRED. A FLASH FLOOD WATCH HAS BEEN ISSUED FOR OUR DELMARVA AND SOUTHERN NEW JERSEY COUNTIES WHERE IT HAS RAINED HEAVILY DURING THE DAY TODAY, AND THE POTENTIAL FOR ADDITIONAL HEAVY RAIN EXISTS. PW VALUES REMAIN HIGH WITH VALUES 1.75-2 INCHES ACROSS THE AREA. MEANWHILE, THE MID-LEVEL TROUGH CONTINUES TO APPROACH THE AREA FROM THE WEST AND SEVERAL VORTICITY IMPULSES WILL CONTINUE TO SLIDE ACROSS THE AREA THROUGH THIS EVENING. ALL OF THIS COMBINED WILL HELP ADDITIONAL SHOWERS AND THUNDERSTORMS DEVELOP. IT HAS ALREADY RAINED ACROSS PORTIONS OF THE WATCH AREA TODAY, AND WHERE IT HAS RAINED, IT`S BEEN VERY HEAVY WITH UP TO 3-4 INCHES IN SOME AREAS IN AN HOUR OR TWO. WITH THE POTENTIAL FOR ADDITIONAL HEAVY RAINFALL ACROSS THESE AREAS, WE HAVE ISSUED A FLASH FLOOD WATCH THROUGH THIS EVENING. THERE ARE SCATTERED SHOWERS AND THUNDERSTORMS MOVING THROUGH CENTRAL AND NORTHEASTERN PENNSYLVANIA, THROUGH THESE HAVE BEEN MOVING AND WILL LIKELY BE MORE DIURNAL IN NATURE AND SHOULD DISSIPATE AROUND SUNSET; SO NO WATCH FURTHER NORTH. WE EXPECT MUCH OF THE PRECIPITATION TO BEGIN TO DIMINISH LATER THIS EVENING AND TOWARD MIDNIGHT AS INSATIABILITY WANES AND PW VALUES BEGIN TO LOWER. THEREFORE THE WATCH ENDS AT LOCAL MIDNIGHT. HOWEVER, WITH THE FRONT REMAINING NEARBY AND THE MID-LEVEL TROUGH STILL TO OUR WEST, THERE WILL STILL BE THE POTENTIAL FOR A FEW SHOWERS AND THUNDERSTORMS INTO FRIDAY MORNING. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/... THE PESKY FRONTAL BOUNDARY IS EXPECTED TO PUSH BACK OFFSHORE ON FRIDAY, AND STALL ACROSS THE OCEAN WATERS TO OUR EAST. PW VALUES CONTINUE TO LOWER THROUGH THE DAY, BUT THE MID-LEVEL THROUGH WILL BE MOVING OVERHEAD THROUGH THE DAY. THERE WILL REMAIN THE CHANCE FOR ISOLATED-SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE AREA, WITH THE BEST POTENTIAL ACROSS SOUTHERN NEW JERSEY AND SOUTHERN DELMARVA. HIGHS ON FRIDAY WILL DEPEND ON HOW MUCH SUNSHINE WE GET, WITH CLOUDY AREAS LIKELY BEING CLOSER TO THE COOLER MET GUIDANCE AND SUNNIER AREAS CLOSER TO THE WARMER MAV GUIDANCE. FOR NOW, WE TOOK A BLEND OF THE MAV/MET/MOSGUIDE FOR DAYTIME HIGHS. && .LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/... SURFACE HIGH PRESSURE CENTERED JUST EAST OF NEW ENGLAND WILL PROVIDE NICE WEATHER THROUGH SATURDAY. FRIDAY NIGHT WILL FEATURE CLEAR SKIES AND COOL TEMPERATURES FOR THIS TIME OF YEAR, AND AN EASTERLY FLOW WILL KEEP HIGHS IN THE 80S ON SATURDAY. CONDITIONS WILL BEGIN TO DETERIORATE SOMEWHAT ON SUNDAY AS A FRONTAL BOUNDARY APPROACHES FROM THE WEST. CLOUDS WILL BE ON THE INCREASE AND SHOWERS AND THUNDERSTORM ACTIVITY WILL BECOME INCREASINGLY LIKELY FROM WEST TO EAST AS THE DAY WEARS ON. THESE CLOUDS SHOULD KEEP THE HIGH TEMPERATURES ON SUNDAY ONE OR TWO DEGREES COOLER THAN SATURDAY. AN ANOMALOUSLY STRONG NRN STREAM CLOSED LOW IS FORECAST TO DIVE SOUTHWARD FROM NEAR HUDSON BAY INTO THE UPPER MIDWEST EARLY NEXT WEEK, SETTING UP A RATHER UNUSUAL PATTERN FOR THIS TIME OF YEAR. THE MID-ATLANTIC REGION WILL BE SITUATED IN AN INCREASINGLY DIFFLUENT FLOW PATTERN ALOFT ON THE SOUTHEASTERN PERIPHERY OF THE AMPLIFYING UPPER TROUGH AND ON THE WESTERN PERIPHERY OF THE WESTERN ATLANTIC RIDGE. THE HEAT AND HUMIDITY WILL RETURN MONDAY AND TUESDAY DURING THIS TIME AS STRENGTHENING SOUTHWESTERLY FLOW AHEAD OF THE LOW BECOMES ESTABLISHED OVER THE EASTERN CONUS. MAX TEMPS IN THE LOWER 90S APPEAR LIKELY MONDAY AND TUESDAY. LEANED TOWARD THE SLOWER ECMWF SOLUTION REGARDING THE ARRIVAL OF THE FROPA ON TUESDAY. RAISED MAX TEMPS A FEW DEGREES FROM 12Z WPC GUIDANCE AS A SLOWER SOLUTION WOULD KEEP THE PRE-FRONTAL WARM AIRMASS THAT IS CHARACTERIZED BY 850 MB TEMPS NEAR 20C OVER THE AREA INTO TUESDAY. MAX TEMPS IN THE LOWER 90S OVER THE COASTAL MID-ATLANTIC REGION FOR ONE MORE DAY. MONDAY AND TUESDAY BOTH LOOK TO BE A RATHER STORMY PERIOD FOR THE AREA. THE FOCUS FOR CONVECTION APPEARS TO BE A PRE-FRONTAL/LEE TROUGH ON MONDAY AND THE MAIN COLD FRONT FOR TUESDAY. FAVORABLE DYNAMICS IN THE RIGHT ENTRANCE REGION OF AN UNSEASONABLY STRONG UPPER-LEVEL JET STREAK AND AHEAD OF THE APPROACHING LONGWAVE TROUGH ALSO LOOKS TO CONTRIBUTE TO SYNOPTIC LIFT OVER THE AREA ON TUESDAY. THERE ARE STILL PLENTY OF DETAILS THAT NEED TO BE WORKED OUT THIS FAR OUT, BUT THE POTENTIAL IS THERE FOR SEVERE THUNDERSTORM EVENTS BOTH DAYS. SPC HAS DEPICTED THE AREA IN A DAY 6 SLIGHT RISK FOR TUESDAY. COLD FROPA LIKELY TUESDAY NIGHT OR EARLY WEDNESDAY. MUCH COOLER AND DRIER CONDITIONS ARE FORECAST TO RETURN BEHIND THE COLD FRONT BY WEDNESDAY. THE 12Z ECMWF INDICATES H8 TEMPS DROPPING INTO THE SINGLE DIGITS BEHIND THE FRONT. && .AVIATION /21Z THURSDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. WE ARE FORECASTING VFR CONDITIONS FOR MOST AREAS THROUGH THE TAF PERIOD. THE EXCEPTION IS MIV/ACY WHERE THERE HAVE BEEN MVFR AND EVEN IFR CIGS/VSBYS ASSOCIATED WITH SHOWERS AND THUNDERSTORMS AND CLOUD COVER FROM THE FRONTAL BOUNDARY OFF THE COAST. THERE COULD BE SOME PATCH FOG OVERNIGHT TONIGHT AS WELL, ESPECIALLY FOR RDG/MIV AND POSSIBLY ACY. THE REST OF THE TAF SITES WE DO NOT ANTICIPATE MUCH FOG POTENTIAL. THERE REMAINS THE POSSIBILITY OF SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON INTO THIS EVENING, ESPECIALLY FOR SOUTHERN NEW JERSEY AND DELMARVA. WE HAVE KEPT ANY SHRA/TSRA GROUP OUT OF THE TAFS EXCEPT AT MIV/ACY. THERE ARE A SOME SHOWERS/THUNDERSTORMS MOVING ACROSS CENTRAL AND NORTHEASTERN PENNSYLVANIA, BUT WE EXPECT THESE TO MOSTLY DISSIPATE AS THEY APPROACH OUR AREA. IF THEY MAINTAIN THEMSELVES, WE WILL AMEND AS NECESSARY. WINDS WILL GENERALLY BE OUT OF THE EAST TO NORTHEAST TODAY, BEFORE GOING LIGHT AND VARIABLE OVERNIGHT, THEN SETTLING BACK TO A NORTHEAST DIRECTION AGAIN ON FRIDAY. THE NAM SHOWS THE POSSIBILITY OF MVFR/IFR CIGS DEVELOPING OVERNIGHT FOR ACY/MIV, SO WE WILL NEED TO MONITOR THIS IN CASE THIS COMES TO FRUITION. OUTLOOK... FRIDAY NIGHT THRU SATURDAY NIGHT...POTENTIAL FOR IFR CIGS WITH MARINE STRATUS TO IMPACT TERMINALS, PARTICULARLY ACY/MIV, FRIDAY AND SATURDAY NIGHTS WITH ONSHORE FLOW. OTHERWISE VFR EXPECTED WITH DRY CONDITIONS. SUNDAY AND MONDAY...CHANCE FOR SHRA/TSRA BOTH DAYS. BETTER CHANCE MAY BE MONDAY WITH A WELL-DEFINED SFC TROUGH DEVELOPING OVER THE EASTERN SEABOARD. LOCAL/BRIEF RESTRICTIONS POSSIBLE. TUESDAY...BETTER CHANCE FOR SHRA/TSRA TUESDAY AS A COLD FRONT APPROACHES. && .MARINE... SUB-ADVISORY CONDITIONS ARE EXPECTED THROUGH TONIGHT AND FRIDAY WITH A FRONTAL BOUNDARY DRAPED ACROSS THE WATERS. THERE REMAINS A CHANCE FOR SHOWERS AND THUNDERSTORMS THROUGH FRIDAY; EXPECT HIGHER WINDS AND WAVES NEAR THUNDERSTORMS. OUTLOOK... FRIDAY NIGHT THROUGH AND SATURDAY NIGHT...HIPRES BUILDS IN FROM THE NORTHEAST STATES TO START THE WEEKEND. ONSHORE FLOW WILL BE LIGHT. SUNDAY THROUGH TUESDAY...WINDS VEER, BECOMING SOUTHWESTERLY ON SUNDAY. SOUTHWEST WINDS STRENGTHEN MONDAY BUT SHOULD REMAIN BELOW SCA LEVELS. GUSTY SOUTHERLY WINDS AHEAD OF A COLD FRONT ON TUESDAY. MARGINAL SCA POSSIBLE. CHANCE FOR SHRA/TSRA LATE SUNDAY. BETTER CHANCE ON MONDAY AND TUESDAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NJZ016- 021>024. DE...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR DEZ001>004. MD...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR MDZ008-012- 015-019-020. MARINE...NONE. && $$ SYNOPSIS...KLEIN NEAR TERM...GIGI/ROBERTSON SHORT TERM...ROBERTSON LONG TERM...KLEIN/MIKETTA AVIATION...KLEIN/ROBERTSON MARINE...KLEIN/ROBERTSON
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
138 PM EDT THU JUL 10 2014 .SYNOPSIS... A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY. A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE MID ATLANTIC REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... UPDATED TO ADD SEVERE TSTM WATCH FOR SE VA/NE NC. PREVIOUS DISCUSSION... LATEST ANALYSIS SHOWING FRONTAL BOUNDARY STALLED OVER WRN PORTIONS OF THE CWA WITH AN AREA OF SHOWERS/EMBEDDED TSTMS DEVELOPING ALONG THE FRONT ACRS MECKLENBURG/LUNENBURG AS OF 11 AM. VERY MOIST AIRMASS IN PLACE ACRS THE REGION WITH PWAT VALUE OVER 2" ON 12Z WAL SOUNDING (AND 1.75-2" AT GSO). 12Z NAM BRINGS PRECIP FARTHER NORTH THAN PREVIOUS RUNS AND IT MAY BE ONTO SOMETHING AS IT IS VERIFYING WELL THUS FAR. HAVE THUS INCREASED POPS TO 70% OVER MUCH OF CENTRAL VA AS FAR N AS METRO RICHMOND THIS AFTN (WELCOME RAINFALL HERE). SATELLITE TRENDS SUGGEST LITTLE CLEARING THIS AFTN...WITH THE POSSIBLE EXCEPTION OF FAR SE VA/NE NC WHERE A BRIEF PERIOD OF PARTIAL CLEARING MAY OVERSPREAD THE REGION OVER THE NEXT FEW HRS BEFORE TSTMS REDEVELOP. MAIN CONCERN TODAY WILL BE FOR HEAVY RAIN AND POSSIBLE FLASH FLOODING HOWEVER SOME STRONG TO SEVERE STORMS WILL BE POSSIBLE IN FAR SE VA/NE NC WHERE INSTABILITY IS A LITTLE HIGHER AND DUE TO DEEP LAYER SHEAR 0-6 KM OF 30-35 KT. MAINLY A STRONG WIND THREAT BUT AN ISOLATED VERY BRIEF WEAK TORNADO NOT OUT OF THE QUESTION GIVEN THE LOW LEVEL BOUNDARY. IR SATELLITE SHOWS DEEP MOISTURE PLUME FROM THE SW AND UPPER JET IS IN A FAVORABLE POSITION (RRQ FORCING) TO SUPPORT LIKELY POPS MOST AREAS THIS AFTN AND TONIGHT. IN ADDITION..SHOULD SEE TRAINING OF STORMS DUE TO LOW LEVEL SW JET BEING NEARLY PARALLEL AND SIMILAR IN MAGNITUDE TO THE FLOW ALOFT (LOW MBE VALUES). MUCH OF HAMPTON ROADS AND NE NC RECEIVED 2" OR MORE OF RAINFALL OVER THE PAST 24 HRS AND MAY NEED TO CONSIDER A FLASH FLOOD WATCH THIS AFTN THROUGH FRI MORNING IN THESE AREAS BUT CONFIDENCE TOO LOW IN PLACEMENT OF HEAVIEST PRECIP (ESPECIALLY GIVEN THE LATEST NAM KEEPING HEAVIER AMTS FARTHER INLAND/NW). WILL CONTINUE MENTION OF LCLLY HEAVY RAINFALL THREAT IN HWO (AND SEVERE THREAT OVER FAR SE VA/NE NC). LOWERED MAX TEMPS A FEW DEGREES WITH HIGHS MAINLY IN THE LOWER-MID 80S. S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY ENHANCE CONVECTION CHCS OVERNIGHT BUT SHOULD KEEP THE THREAT OF PCPN GOING THROUGH THE NIGHT...PARTICULARLY ACRS SE VA/NE NC. POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES. LOWS M60S FAR NW TO LWR-MID 70S SE. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY EXITING OFF THE COAST DURING THE AFTN. DATA SHOWS PLENTY OF MSTR ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70 F. MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY SUNNY WITH HIGHS IN THE M-U80S. QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5 IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL APPALACHIANS. FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT. THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM 1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT). THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT. EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS BASED ON THE FRONT LIKELY STALLING OFFSHORE. TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER 80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S. OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID 70S NEAR THE COAST. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10 THOUSAND FEET. FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION LATE SUNDAY OR MONDAY. && .MARINE... SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN 2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED MORNING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB/MPR LONG TERM...SAM AVIATION...JAB MARINE...JAB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1252 PM EDT THU JUL 10 2014 .SYNOPSIS... A FRONTAL BOUNDARY STALLS OVER THE REGION TODAY THROUGH FRIDAY. A WEAK AREA OF LOW PRESSURE MOVES NORTHEAST ALONG THIS BOUNDARY TONIGHT THEN PUSHES OFFSHORE FRIDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE MID ATLANTIC REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... LATEST ANALYSIS SHOWING FRONTAL BOUNDARY STALLED OVER WRN PORTIONS OF THE CWA WITH AN AREA OF SHOWERS/EMBEDDED TSTMS DEVELOPING ALONG THE FRONT ACRS MECKLENBURG/LUNENBURG AS OF 11 AM. VERY MOIST AIRMASS IN PLACE ACRS THE REGION WITH PWAT VALUE OVER 2" ON 12Z WAL SOUNDING (AND 1.75-2" AT GSO). 12Z NAM BRINGS PRECIP FARTHER NORTH THAN PREVIOUS RUNS AND IT MAY BE ONTO SOMETHING AS IT IS VERIFYING WELL THUS FAR. HAVE THUS INCREASED POPS TO 70% OVER MUCH OF CENTRAL VA AS FAR N AS METRO RICHMOND THIS AFTN (WELCOME RAINFALL HERE). SATELLITE TRENDS SUGGEST LITTLE CLEARING THIS AFTN...WITH THE POSSIBLE EXCEPTION OF FAR SE VA/NE NC WHERE A BRIEF PERIOD OF PARTIAL CLEARING MAY OVERSPREAD THE REGION OVER THE NEXT FEW HRS BEFORE TSTMS REDEVELOP. MAIN CONCERN TODAY WILL BE FOR HEAVY RAIN AND POSSIBLE FLASH FLOODING HOWEVER SOME STRONG TO SEVERE STORMS WILL BE POSSIBLE IN FAR SE VA/NE NC WHERE INSTABILITY IS A LITTLE HIGHER AND DUE TO DEEP LAYER SHEAR 0-6 KM OF 30-35 KT. MAINLY A STRONG WIND THREAT BUT AN ISOLATED VERY BRIEF WEAK TORNADO NOT OUT OF THE QUESTION GIVEN THE LOW LEVEL BOUNDARY. IR SATELLITE SHOWS DEEP MOISTURE PLUME FROM THE SW AND UPPER JET IS IN A FAVORABLE POSITION (RRQ FORCING) TO SUPPORT LIKELY POPS MOST AREAS THIS AFTN AND TONIGHT. IN ADDITION..SHOULD SEE TRAINING OF STORMS DUE TO LOW LEVEL SW JET BEING NEARLY PARALLEL AND SIMILAR IN MAGNITUDE TO THE FLOW ALOFT (LOW MBE VALUES). MUCH OF HAMPTON ROADS AND NE NC RECEIVED 2" OR MORE OF RAINFALL OVER THE PAST 24 HRS AND MAY NEED TO CONSIDER A FLASH FLOOD WATCH THIS AFTN THROUGH FRI MORNING IN THESE AREAS BUT CONFIDENCE TOO LOW IN PLACEMENT OF HEAVIEST PRECIP (ESPECIALLY GIVEN THE LATEST NAM KEEPING HEAVIER AMTS FARTHER INLAND/NW). WILL CONTINUE MENTION OF LCLLY HEAVY RAINFALL THREAT IN HWO (AND SEVERE THREAT OVER FAR SE VA/NE NC). LOWERED MAX TEMPS A FEW DEGREES WITH HIGHS MAINLY IN THE LOWER-MID 80S. S/W ENERGY TRACKS NE ALONG THE BNDRY TONIGHT. THIS WILL NOT ONLY ENHANCE CONVECTION CHCS OVERNIGHT BUT SHOULD KEEP THE THREAT OF PCPN GOING THROUGH THE NIGHT...PARTICULARLY ACRS SE VA/NE NC. POPS WOULD LIKELY HAVE TO BE RAISED FURTHER WEST IF NAM VERIFIES. LOWS M60S FAR NW TO LWR-MID 70S SE. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... SYSTEM LINGERS ALONG COASTAL AREAS FRIDAY MORNING BEFORE SLOWLY EXITING OFF THE COAST DURING THE AFTN. DATA SHOWS PLENTY OF MSTR ARND ALONG WITH SOME INSTABILITY TO INCLUDE CHC POPS THROUGH THE DAY WITH THE HIGHEST POPS SERN AREAS. HIGHS GNRLY IN THE M80S. SCT EVENING POPS FRI NIGHT...OTW BCMG PT CLDY. LOWS 65-70. MODELS INDICATING THE FRONT WASHES OUT / DISSIPATES ACROSS THE AREA SAT. KEPT A 20-30% POP OVER THE FAR NW AND IN SE VA/NE NC. PARTLY SUNNY WITH HIGHS IN THE M-U80S. QPF NXT 72 HRS AVGG 2/3RDS TO 1 IN ACROSS NWRN AREAS...1 TO 1.5 IN ACROSS CNTRL AREAS...1.5 TO 2.5 ACROSS SERN VA/NE NC. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AMPLIFIED UPPER FLOW OVER THE HIGHER LATITUDES WILL PUSH ANOTHER ANOMALOUS TROUGH INTO THE NERN CONUS EARLY NEXT WEEK. THE RESULT WILL BE BELOW NORMAL TEMPS AND WET CONDITIONS FROM THE UPPER MIDWEST TO THE OH VALLEY. HOWEVER...THE LOCAL AREA REMAINS SEASONABLY WARM AS MUCH OF THE COOLER AIR WILL BE LOCKED WEST OF THE CNTRL APPALACHIANS. FOR THE LATTER HALF OF THE WEEKEND...ONGOING RETURN FLOW ON THE BACKSIDE OF HIGH PRESSURE ANCHORED OVER THE WRN ATLANTIC WILL RESULT IN SLIGHTLY WARMER TEMPS AND DEWPOINTS SUN COMPARED TO SAT. THICKNESSES YIELD TEMPS RIGHT AROUND 90 DEGS. A COLD FRONT WILL PUSH INTO THE GREAT LAKES REGION SUN WITH SFC TROUGHING DEVELOPING OVER THE LOCAL AREA. THETA-E ADVECTION AND A MOIST BL WILL RESULT IN MLCAPE VALUES ~1500 J/KG. MODEL DERIVED PRECIP WATERS RANGE FROM 1.75 TO 2 INCHES. WHILE MOISTURE/INSTABILITY LOOK FAVORABLE...BEST DYNAMICS/FORCING REMAINS WELL WEST OF THE AREA WITH THE BETTER HEIGHT FALLS AND STRONGER WINDS ALOFT. SHEAR IS ALSO UNIMPRESSIVE AND SOUNDINGS DEPICT SUBSIDENCE/WARM AIR ALOFT. WILL CARRY CHANCE POPS IN THE NW...TAPERING OFF TO SILENT IN THE SE. BETTER COVERAGE EXPECTED MON AS HEIGHT FALLS AND INCREASING WINDS ALOFT PROVIDE BETTER FORCING FOR ASCENT AND COOLER MID-LEVEL TEMPS. COLD FRONT IS EXPECTED TO REACH THE CNTRL APPALACHIANS LATE MON...SHARPENING THE THERMAL TROUGH OVER THE LOCAL AREA. WARMER TEMPS AND DEWPOINTS WILL PUSH MLCAPE VALUES HIGHER...BUT SHEAR REMAINS MARGINAL (AOB 20 KT). THE RESULT WILL BE SCT AFTERNOON SHOWERS/THUNDERSTORMS ACROSS MUCH OF THE REGION. COLD FRONT DROPS INTO THE REGION TUES-TUES NIGHT. EXACT TIMING OF THE FRONT WILL IMPACT SENSIBLE WEATHER OVER THE LOCAL AREA. WILL TREND TOWARD A BLEND BTWN THE MEDIUM RANGE GUIDANCE...KEEPING THE BEST POPS ALONG THE COAST TUES. BASED ON THE AIRMASS...WILL ALSO CARRY SLIGHT CHANCE POPS MON NIGHT-TUES MORNING AS THE FRONT CROSS THE REGION. UPPER LOW BEGINS TO EJECT FROM THE GREAT LAKES REGION TUES INTO SE CANADA...SLOWING THE FRONT AS IT PUSHES OFFSHORE TUES NIGHT-WEDS MORNING. CONFIDENCE IS NOT HIGH ATTM...BUT WILL HANG ON TO SLIGHT CHANCE POPS ALONG THE COAST WEDS BASED ON THE FRONT LIKELY STALLING OFFSHORE. TEMPS WILL REMAIN AROUND SEASONABLE NORMS...WARMING INTO THE UPPER 80S-LOW 90S THRU THE PERIOD. ANTICIPATE TUES TO BE THE WARMEST IN ADVANCE OF THE FRONT...WITH HIGHS GENERALLY IN THE LOW 90S. OVERNIGHT LOWS WILL GENERALLY BE IN THE UPPER 60S-LOW 70S...WITH MID 70S NEAR THE COAST. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... TSTMS CONTINUE TO DEVELOP ALONG THE ALBEMARLE SOUND. THIS IS ALONG THE OUTFLOW FROM THE EARLIER CONVECTION. LOOKING AT THE HRRR THINK THESE WILL FINALLY END BY AROUND 14Z. WILL HAVE A TEMPO GROUP AT KECG AS THESE TSTMS COULD MOVE ACROSS THERE AT TIMES. UPPER TROF CONTINUES ACROSS THE AREA TODAY. THERE WILL BE SEVERAL BOUNDARIES ACROSS THE AREA WHICH COULD FOCUS CONVECTION THIS AFTERNOON INTO TONIGHT. ALL MODELS AGREE ON CONVECTION DEVELOPING JUST NOT SURE WHETHER TO THE WEST MOSTLY RECEIVES IT OR BACK ACROSS THE SOUTHEAST. MOST HI RES MODELS ARE LEANING TOWARD SE VA AND NE NC SO WILL PUT A TEMPO GROUP IN THAT AREA THIS AFTERNOON. HOWEVER THINK MOST AREAS WILL GO TO MVFR OR EVEN IFR IN TSTMS SOMETIME THIS AFTERNOON OR TONIGHT. WITH DIMINISHING FLOW BY TONIGHT ANY THUNDERSTORMS THAT DO FORM WILL BE SLOW TO MOVE. OUTSIDE OF THE PRECIPITATION EXPECT VFR CONDITIONS WITH SOME CLOUDS AROUND 10 THOUSAND FEET. FRONT CROSSES AREA BY FRIDAY...LEAVING FRI NGT/SAT DRY ATTM. NEXT FRONT COULD BRING THE POTENTIAL FOR MORE SHWRS/TSTMS TO THE REGION LATE SUNDAY OR MONDAY. && .MARINE... SUB-SCA CONDITIONS ARE EXPECTED OVER THE WATERS THROUGH THE WEEK. A WEAK TROF IS TO THE WEST OF THE WATERS KEEPING MAINLY A LIGHT SOUTHERLY WIND OVER THE WATERS. A WEAK LOW PRESSURE SYSTEM WILL MOVE ALONG THIS BOUNDARY TONIGHT AND FRIDAY. THIS WILL ALLOW THE WINDS TO BE MORE SOUTHEAST AT TIMES. AFTER THE LOW MOVES PAST FRIDAY NIGHT THE TROF WILL MOVE OFF THE COAST SATURDAY. WILL HAVE LIKELY THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER THE SOUTHERN WATERS WITH A CHANCE ACROSS THE NORTHERN WATERS.SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE WATERS FRIDAY INTO FRIDAY NIGHT. WINDS WILL BECOME MORE WEST TO NORTH OVER THE WEEKEND. FLOW VEERS TO THE SOUTH SUN...REMAINING SUB SCA AT 10-15 KT. SEAS REMAIN 2-3 FT. LOW PRESSURE LIFTS INTO THE GREAT LAKES REGION MON AS A COLD FRONT PUSHES INTO THE OH VALLEY. GRADIENT WILL STRENGTHEN SLIGHTLY OVER THE WATERS SUN NIGHT-MON...BUT REMAINS SUB-SCA. PERSISTENT SLY FLOW WILL PUSH SEAS TO 4 FT IN THE NRN WATERS...BUT ANTICIPATE SEAS TO REMAIN UNDER 5 FT. COLD FRONT CROSSES THE WATERS TUES NIGHT-WED MORNING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB/MPR LONG TERM...SAM AVIATION...JAB MARINE...JAB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
327 PM CDT THU JUL 10 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 325 PM CDT THU JUL 10 2014 MAIN CONCERN FOR THE SHORT TERM IS TURNING OUT TO BE THE POTENTIAL FOR HEAVY RAIN TONIGHT OVER WESTERN MN BASED ON LATEST HI-RES CAMS. THIS AFTERNOON...SRLY LOW LEVEL WINDS HAVE BECOME WELL ESTABLISHED AS HIGH PRESSURE HAS NOW PUSHED OFF TO MICHIGAN. THESE SRLY WINDS HAVE FINALLY BROUGHT THE CANADIAN SMOKE PLUME THAT WAS LINGERING JUST TO OUR SW THE PAST COUPLE OF DAYS UP INTO CENTRAL AND SRN MN...HENCE THE MILKY COLOR IN THE SKY AND OCCASIONAL HAZE REPORTS ACROSS THE AREA THIS AFTERNOON. BACK TO THE WEST...A SHORT WAVE CAN BE SEEN APPROACHING WRN MN...THOUGH THIS HAS DONE NOTHING MORE THAN CREATE MAINLY VIRGA...AND THIS IS EXPECTED TO BE THE CASE AS IT WORKS ACROSS MN THIS EVENING. INSTEAD...THE MAIN WAVE DRIVING THE WEATHER ACROSS THE NRN PLAINS IS THE CUT-OFF H5 LOW CURRENTLY SPINNING FROM ALBERTA INTO SASKATCHEWAN. THIS WAVE IS WHAT IS FORCING THE LLJ TO BE BACK MORE ACROSS CENTRAL INTO THE ERN DAKOTAS TODAY. FOR THIS AFTERNOON INTO TONIGHT...FAVORED THE FORECAST FOR POPS AND QPF TOWARD THE RAP/ECMWF ALONG WITH JUST ABOUT ANY HI-RES CAM YOU CAN FIND THAT WAS RUN AT 12Z OR LATER. ALL OF THESE MODELS SHOW THUNDERSTORMS DEVELOPING OVER NE SODAK AROUND 21/22Z AND SLOWLY WORKING EAST INTO WRN MN THIS EVENING. ALL HI-RES MODELS SHOW 2-4 INCHES OF RAIN FALLING IN THE GENERALLY VCNTY OF THE NE SODAK/WRN MN BORDER. LOOKING AT THE RAP...THIS LOOKS TO BE TIED TO WHAT IS HAPPENING IN THE 925-850MB LAYER. THE RAP HAS BEEN PRETTY CONSISTENT WITH SHOWING MOISTURE TRANSPORT IN THIS LAYER INCREASING THIS AFTERNOON ACROSS SE SODAK...WITH THE EDGE OF IT UP INTO NE SODAK. IN ADDITION TO THAT...THE RAP SHOWS A STRONG FGEN SIGNAL AT THE NOSE OF THIS LLJ. THE REASON FOR THE HEAVY PRECIP SIGNAL IS THIS LLJ AND ITS ASSOCIATED FGEN REMAIN MORE OR LESS STATIONARY OUT NEAR THE MN/SD BORDER THROUGH ABOUT 6Z. WITH THIS FORCING REMAINING STATIONARY...THERE WILL BE A PERIOD THROUGH ABOUT 6Z WHERE THE ACTIVITY CAN TRAIN OUT THERE...BEFORE EVERYTHING STARTS TO BECOME MORE PROGRESSIVE LATE TONIGHT AS THE CANADIAN UPPER LOW MOVES TOWARD MANITOBA. QPF GRIDS USED WERE A BLEND OF THE SHORT TERM CAMS TEMPERED WITH THE 12Z ECMWF. THIS RESULTED IN 1-2 INCHES OF QPF THROUGH FRI MORNING OUT IN WRN MN...WHICH MAY STILL BE CONSERVATIVE CONSIDERING SOME OF THE HI-RES MODELS HAVE BEEN SHOWING THE POTENTIAL FOR ISOLATED RAINFALL AMOUNTS OVER 5 INCHES TONIGHT...SO THIS IS SOMETHING THAT CERTAINLY BEARS SOME WATCHING. THROUGH THE REST OF THE SHORT TERM...THE LLJ AND SFC FRONT WILL SLOWLY WORK EAST WITH TIME DURING THE MORNING ON FRIDAY...WITH BEST RAINFALL CHANCES FOR ERN MN/WRN WI LIKELY COMING DURING THE MORNING AS REMNANTS OF TONIGHTS ACTIVITY SHIFTS EAST. BACKED OFF SOME ON POPS FRIDAY AFTERNOON...AS CAMS ARE FAIRLY SPARSE WITH ACTIVITY AS WE LOOSE THE DEFINITION ON THE SFC FRONT...WHICH WILL COINCIDE WITH A WEAKENING OF THE LLJ AS WE GET INTO SUBSIDENCE ASSOCIATED WITH THE RIGHT ENTRANCE REGION OF THE UPPER JET WORKING ACROSS THE INTERNATIONAL BORDER. WITH LESS ACTIVITY EXPECTED...ALSO BOOSTED TEMPS A FEW DEGREES OUT IN WRN WI AS IT IS NOT LOOKING AS LIKELY FOR FRIDAY TO BE DOMINATED BY CLOUDS AND RAIN AS WAS PREVIOUSLY ANTICIPATED. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 PM CDT THU JUL 10 2014 AS WE PROGRESS THROUGH THE SATURDAY-THURSDAY PERIOD WE/LL SEE QUITE THE EVOLUTION OF LARGE SCALE FEATURES AND WEATHER ACROSS THE AREA. THINGS WILL START OUT WARM WITH THE UPPER JET NORTH OF THE AREA... BUT AN UNSEASONABLY DEEP UPPER LOW WILL DROP SOUTH/EAST FROM CENTRAL CANADA INTO THE UPPER MIDWEST AND GREAT LAKES REGION DURING THE SUNDAY NIGHT THROUGH TUESDAY PERIOD. THIS WILL BRING VERY COOL TEMPERATURES TO MUCH OF THE REGION... WITH THE HEART OF THE COLD AIR TRACKING ACROSS MINNESOTA AND POINTS EAST. SOME PCPN CHANCES WILL LOITER ACROSS THE REGION SATURDAY INTO SUNDAY PRIOR TO THE ARRIVAL OF THE COLD FRONT AND UPPER TROUGH... WITH DIURNAL CHANCES FOR PCPN AFTER THAT AS THE UPPER COLD POOL SWINGS ACROSS THE REGION. BEST CHANCES FOR PCPN PRIOR TO FROPA WILL BE ACROSS THE SOUTHERN PORTIONS OF THE AREA WHERE THE BAROCLINIC ZONE AND BEST INSTABILITY ARE PROGGED... WITH CHANCES FOR DIURNAL SHRA FOLLOWING FROPA LOCATED OVER EASTERN AREAS WHERE BOUNDARY LAYER CYCLONIC FLOW WILL BE MOST PREVALENT AND LOW-MID LEVEL LAPSE RATES WILL BE STEEPEST BENEATH THE MID-UPPER LEVEL COLD POOL. WE WILL SEE RIDGING BEGIN TO WORK INTO THE AREA AFTER TUESDAY... WITH DRY WEATHER AND MODERATING TEMPERATURES FOR THE LAST FEW DAYS OF THE FORECAST PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1250 PM CDT THU JUL 10 2014 MAIN DISTURBANCE IS NOW OVER NORTHERN SODAK WHICH WILL BE GENERATING SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND TONIGHT AS IT HEADS EAST TOWARD MN. DEFORMATION AREA TO THE WEST OF THIS DISTURBANCE ALONG THE MT/WY BORDER WILL ALSO FOSTER STORM DEVELOPMENT THIS EVENING...SO IT LOOKS LIKE A FAIRLY STORMY EVENING AND OVERNIGHT ACROSS WEST CENTRAL AND PORTIONS OF CENTRAL MN. HEAVY RAIN POTENTIAL IS INCREASING WITH SEVERAL INCHES POSSIBLE...BUT IT IS STILL SOMEWHAT UNCLEAR WHICH TAF SITES WILL BE MOST IMPACTED. AT THIS POINT IT LOOKS LIKE IT WILL SET UP JUST SOUTH OF AXN/STC AND NORTH OF RWF THROUGH 06Z...EXPANDING EASTWARD TOWARD MSP BETWEEN 08-11Z. MAINLY VFR CONDITIONS EXPECTED... HOWEVER HEAVY RAINFALL WOULD BRING MUCH LOWER CONDITIONS. KMSP...LITTLE CONCERNS THIS AFTERNOON AND EVENING. BIGGEST CONCERN COMES LATE TONIGHT AND FRIDAY MORNING IF MESOSCALE MODELS ARE CORRECT IN BRINGING A NARROW BAND OF HEAVY RAINFALL. /OUTLOOK FOR KMSP/ SAT...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WIND NW AT 5 KTS. SUN...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WINDS W AT 5-10 KTS. MON...VFR WITH MVFR CIGS/SHRA POSSIBLE. WIND NW AT 10-20 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...TRH AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
343 PM CDT THU JUL 10 2014 .SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT SHORT WAVE TROUGH CLOUD COVER AND SCATTERED LIGHT SHOWERS HAVE LESSENED THE BUILDUP OF INSTABILITY ACROSS THE REGION LATE THIS AFTERNOON. THE SPC ANALYSIS SHOWED ONLY 500 TO 1500 J/KG OF MIXED LAYER CAPE FROM NORTH TO SOUTH ACROSS THE CWA LATE THIS AFTERNOON. ALTHOUGH...THE DEEP LAYER SHEAR WAS IMPRESSIVE UP TO OVER 50 KNOTS. EXPECT SOME MORE BUILDUP OF INSTABILITY INTO THE EVENING ACROSS THE CWA AS CLOUDS AND LIGHT SHOWERS MOVE EAST. THE GFS AND HI-RES MODELS STILL SHOWING NUMEROUS SHOWERS/STORMS DEVELOPING MAINLY ACROSS THE EASTERN CWA THIS EVENING. CENTRAL SD ALSO SEEING MORE SUNSHINE AND WARMING LATE THIS AFTERNOON. WITH AN INCREASING 85H LLJ ACROSS MAINLY THE EAST THIS EVENING...EXPECT A GOOD CHANCE OF SHOWERS/STORMS ACROSS THIS REGION. INCREASED POPS THIS EVENING. THE MODELS THEN SHOW A WEAK BOUNDARY DROPPING SLOWLY SOUTHEAST TONIGHT AND FRIDAY BRINGING WINDS AROUND TO THE EAST AND NORTHEAST ACROSS MOST OF THE CWA. AFTER THE CONVECTION TONIGHT...EXPECT MOST OF FRIDAY TO NOW BE DRY ACROSS THE CWA. THE MODELS THEN SHOW ANOTHER SHORT WAVE TROUGH FROM THE NORTHWEST DROPPING ACROSS THE CWA FRIDAY NIGHT AND SATURDAY ALONG WITH A GOOD JET STREAK DEVELOPING TO OUR NORTH AND NORTHEAST. THIS WILL PUT US IN THE FAVORABLE RR QUADRANT. THUS...HAVE IN CHANCES OF MAINLY ELEVATED SHOWERS/STORMS FOR FRIDAY NIGHT AND SATURDAY WITH EVERYTHING MOVING OFF TO THE SOUTHEAST SATURDAY NIGHT. HIGHS WILL BE IN THE 80S ON FRIDAY AND A FEW DEGREES COOLER ON SATURDAY. .LONG TERM...SUNDAY THROUGH THURSDAY SUNDAY SHOULD PROVE TO BE THE WARMEST DAY OF THE EXTENDED FORECAST PERIOD...WITH ANOMALOUSLY COOL AIR ADVECTING DOWN INTO THE CWA MONDAY AND STICKING AROUND THROUGH PROBABLY WEDNESDAY...AT LEAST. THIS SHOULD SPELL SOME MUCH BELOW NORMAL TEMPERATURES THROUGHOUT THE PERIOD AND DRY CONDITIONS THROUGHOUT THE PERIOD. COLD AIR INSTABILITY CU/STRATO-CU WILL LIKELY ONLY ADD INSULT TO INJURY ON MONDAY CLOUDING THINGS UP AND KEEPING JULY INSOLATION FROM TAKING THE EDGE OFF THE COLDNESS OF THE AIR ON MONDAY. && .CLIMATOLOGICALLY... AN ANOMALOUSLY COLD LOW PRESSURE SYSTEM WILL MOVE INTO UPPER MIDWEST EARLY NEXT WEEK. THE COMBINATION OF A COOL CANADIAN AIRMASS ALONG WITH INCREASING CLOUDS AND A CHANCE FOR SHOWERS COULD RESULT IN A FEW RECORD LOW HIGH TEMPERATURES ON MONDAY. BELOW IS A LIST OF LOCATIONS THAT COULD SEE NEAR RECORD COLD READINGS ON MONDAY: ...LOCATION......FORECAST....RECORD LOW HIGH TEMP... WHEATON MN 64 72 IN 1949 SISSETON 65 70 IN 1993 WATERTOWN 65 61 IN 1962 ABERDEEN 67 65 IN 1962 MOBRIDGE 69 64 IN 1962 PIERRE 72 65 IN 1989 && && .AVIATION... 18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS A RETURN FLOW SURFACE PRESSURE PATTERN WILL KEEP WINDS SOUTH- SOUTHEAST OVER MUCH OF THE TAF VALID PERIOD AT KABR/KATY. A COLD FRONT APPROACHING FROM THE NORTHWEST SHOULD BEGIN TO SWITCH WINDS AROUND TO NORTH-NORTHEAST AT KPIR/KMBG BY FRIDAY MORNING. SOME OF THE AVAILABLE GUIDANCE SUGGESTS PREVAILING VFR CONDITIONS MAY DIP INTO MVFR/IFR FLT CATEGORY /PARTICULARLY AT KATY/ DUE TO POSSIBLE LOW CIGS LATER TONIGHT INTO FRIDAY MORNING GIVEN THE AMOUNT OF AVAILABLE LOW LEVEL MOISTURE. IF THUNDERSTORMS DEVELOP EARLY THIS EVENING AND RUMBLE OVER KABR/KATY...THE LIKELIHOOD OF LOW CIGS DEVELOPING LATE TONIGHT/EARLY FRIDAY MORNING BEGINS TO INCREASE. THERE IS ALSO A CHANCE OF THUNDERSTORMS DEVELOPING BY EARLY THIS EVENING ALONG THIS APPROACHING COLD FRONT...AS WELL AS IN THE LEE OF THE BLACK HILLS SURFACE LOW...WHICH COULD REACH ALL THE WAY TO KMBG/KPIR BEFORE FIZZLING OUT. HOWEVER...THE KMBG/KPIR TERMINALS STAND A BETTER CHANCE OF REMAINING VFR THROUGH THE ENTIRE TAF VALID PERIOD. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...MOHR LONG TERM...DORN AVIATION...DORN WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1211 PM CDT THU JUL 10 2014 .UPDATE... A PREVIOUSLY DIMINISHING MCS OVER EASTERN OK WAS BEGINNING TO REORGANIZE AS IT MOVED INTO NORTHWEST AR A MIDDAY. HRRR SUGGESTS CONVECTION WILL CONTINUE INTO CENTRAL AR... BEFORE DIMINISHING OVER THE EAST AR DELTA BY 8 PM. GIVEN THAT THE HRRR IS A LITTLE BEHIND ON THE EASTWARD PROGRESS OF THE MCS... HAVE ADDED A SLIGHT CHANCE OF THUNDERSTORMS TO PORTIONS OF EAST AR LATE THIS AFTERNOON INTO EARLY EVENING. PWB && .PREV DISCUSSION... /ISSUED 1153 AM CDT THU JUL 10 2014/ UPDATE... UPDATED TO INCLUDE THE 18Z AVIATION DISCUSSION BELOW. JCL PREV DISCUSSION... /ISSUED 429 AM CDT THU JUL 10 2014/ CURRENTLY... AS OF 4AM...TEMPERATURES RANGE FROM THE MID 60S TO LOWER 70S ACROSS THE MID-SOUTH. THE AREA IS FREE OF RAIN FOR THE MOMENT...WITH PATCHY FOG ACROSS THE MAJORITY OF THE REGION. SHOWERS AND THUNDERSTORMS ARE PASSING JUST TO THE SOUTH OF THE FORECAST AREA ALONG A WEAK CONVERGENCE ZONE OVER THE ARKLATEX REGION. FURTHER UPSTREAM...AN MCS IS DIVING SOUTHEAST ACROSS KANSAS AND NORTHERN OKLAHOMA. DEWPOINTS HAVE LOWERED SLIGHTLY ACROSS THE NORTHERN TIER OF THE CWA...HOWEVER READINGS ARE STILL IN THE UPPER 60S AND LOWER 70S ACROSS MOST OF THE AREA AS THE FRONTAL BOUNDARY HAS PRETTY MUCH WASHED OUT. SHORT TERM...TODAY THROUGH SATURDAY... A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON OVER SOUTHERN PORTIONS OF THE FORECAST AREA. THIS AREA WILL HAVE THE BEST COMBINATION OF LOW LEVEL MOISTURE AND INSTABILITY ALLOWING FOR A FEW DAYTIME SHOWERS TO POP UP. THE REST THE OF THE REGION WILL REMAIN DRY AS SURFACE HIGH PRESSURE BUILDS IN FROM THE NORTH. IT SHOULD BE A NICE DAY ACROSS THE REGION WITH MOSTLY CLEAR SKIES AND TEMPERATURES IN THE UPPER 80S TO AROUND 90 DEGREES. FRIDAY AND SATURDAY WILL BE MOSTLY DRY AS A WEAK UPPER LEVEL RIDGE BUILDS IN OVER THE MID-SOUTH. EXPECT TEMPERATURES TO BE NEAR OR SLIGHTLY ABOVE SEASONAL READINGS IN THE LOWER TO MID 90S DURING THE DAY. A STRAY SHOWER OR THUNDERSTORM CANNOT BE TOTALLY RULED OUT DUE TO THE HOT AND HUMID AIRMASS...BUT DECIDED TO LEAVE MENTIONABLE POPS OUT OF THE FORECAST AS CHANCES WILL BE ISOLATED AT BEST. LONG TERM...SUNDAY THROUGH MIDDLE OF NEXT WEEK... BY SUNDAY...SURFACE HIGH PRESSURE WILL SHIFT TO THE NORTHEAST AND WINDS WILL TURN AROUND TO THE SOUTH DRAMATICALLY INCREASING LOW LEVEL MOISTURE OVER THE REGION. THE LONGWAVE TROUGH THAT HAS RESIDED OVER THE EASTERN TWO THIRDS OF THE COUNTRY FOR THE LAST FEW DAYS WILL SHIFT BACK SOUTH INTO OUR AREA. HEIGHT FALLS WILL BEGIN TO TAKE PLACE LATE SUNDAY NIGHT INTO MONDAY AFTERNOON TRIGGERING A FEW SHOWERS AND THUNDERSTORMS OVER THE NORTHERN PORTION OF THE FORECAST AREA. BY MONDAY NIGHT...MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT ON A COLD FRONT DROPPING INTO THE MID-SOUTH FROM THE NORTHWEST. TIMING AND THE POSSIBILITY OF SEVERE WEATHER IS STILL A LITTLE QUESTIONABLE BEING NEARLY FIVE DAYS OUT. FOR NOW...IT APPEARS THAT THE FRONTAL PASSAGE LOOKS PRETTY SIMILAR TO WHAT WE HAD THIS PAST TUESDAY EXCEPT FOR MUCH COOLER AIR BEHIND IT. REST OF THE WEEK...NORTHWEST FLOW ALOFT WILL CONTINUE TO DOMINATE THE WEATHER PATTERN THROUGH THE END OF THE WEEK...EFFECTIVELY KEEPING THE MID-SOUTH WET WITH BELOW NORMAL TEMPERATURES. AC3 && .AVIATION... 18Z TAF CYCLE (10/18Z-11/18Z) VFR CONDITIONS WILL PREVAIL DURING THE PERIOD...THE EXCEPTION WILL BE MVFR VISIBILITIES IN FOG AT KMKL AND KTUP 11/08Z-11/12Z. LIGHT WINDS WILL OCCUR DURING THE PERIOD. JCL && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$