Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/10/13


AREA FORECAST DISCUSSION...CORRECTED
NWS EUREKA CA
1136 PM PDT FRI JUN 7 2013 .SYNOPSIS... TEMPERATURES WILL CONTINUE TO HEAT UP INLAND THROUGH SATURDAY WITH WIDESPREAD SUNSHINE AS UPPER LEVEL HIGH PRESSURE BUILDS OVER THE WEST COAST. THERE MAY BE ISOLATED THUNDERSTORMS OVER THE INTERIOR MOUNTAINS LATE ON SUNDAY. THE IMMEDIATE COAST WILL CONTINUE TO BATTLE AREAS OF LOW CLOUDS...BUT THE BULK OF THE WEEKEND WILL HAVE SOME SUNSHINE AND TEMPERATURES INTO THE 60S. && .DISCUSSION... TEMPERATURES ARE SEVERAL DEGREES WARMER THAN YESTERDAY ON AVERAGE ACROSS NORTHWEST CALIFORNIA...RANGING FROM THE LOW 100S ACROSS THE INTERIOR VALLEYS TO THE 60S ALONG THE COAST. MODEL FORECAST 850 MB TEMPS WILL WARM ANOTHER 1-2C...PEAKING NEAR 27-28C ON SATURDAY AFTERNOON AS UPPER-LEVEL RIDGING CRESTS DIRECTLY OVER NRN CA. THIS WILL ALLOW FOR MID 100S AT LEAST...WHICH WILL BE ABOVE DAILY RECORDS FOR EARLY JUNE ACROSS SEVERAL INTERIOR LOCATIONS. AN UPPER LEVEL TROUGH WILL APPROACH FROM OFF THE SOUTHERN CA COAST ON SUNDAY... RESULTING IN A NOTICEABLY COOLER AND MORE MOIST ATMOSPHERE. MODELS HAVE BECOME FAIRLY CONSISTENT ON THE TRACK OF THIS SYSTEM, BUT HAVE BEEN TRENDING A BIT SLOWER...WHICH WOULD TEND TO PUSH THE TIMING OF ANY THUNDERSTORM ACTIVITY BACK UNTIL LATE IN THE DAY SUNDAY OR SUNDAY NIGHT. WHILE CONFIDENCE HAS INCREASED IN THUNDERSTORM ACTIVITY...EXPECT THE COVERAGE WILL BE ISOLATED AND MAINLY RESTRICTED TO THE MOUNTAINS OF EASTERN TRINITY AND MENDOCINO COUNTIES. WHILE PWS ON FORECAST SOUNDINGS APPROACH 1 INCH SUNDAY NIGHT...NEARLY ALL OF THE MOISTURE WILL BE ABOVE 500 MB...OR AT LEAST SEVERAL THOUSAND FEET ABOVE THE HIGHEST TERRAIN. THIS MEANS THE ACTIVITY WILL BE RATHER HIGH BASED WITH LITTLE ACCOMPANYING RAINFALL. GENERAL TROUGHING WILL DROP IN FROM THE NORTHWEST AND PERSIST NEXT WEEK...RESULTING IN AN EXTENDED PERIOD OF RELATIVELY COOLER BUT MORE SEASONABLE TEMPERATURES AND DRY WEATHER. MEANWHILE AT THE COAST...MID AND UPPER LEVEL RIDGING WILL CONTINUE TO BUILD OVER AN INCREASINGLY SHALLOW MARINE LAYER. THE NORTHERLY GRADIENT HAS INTENSIFIED TODAY...WITH SFC RIDGING BUILDING, RESULTING IN BETTER MIXING AND DRYING OF THE BOUNDARY LAYER. TONIGHT WILL START OFF CLEAR...BUT EXPECT SOME MOISTURE CONVERGENCE INTO THE EEL RIVER VALLEY AND HUMBOLDT BAY AND PERHAPS AROUND FORT BRAGG...RESULTING IN CLOUDS THERE THE NEXT COUPLE OF MORNINGS. DO NOT SEE ANY INDICATIONS OF THE THERMAL TROUGH PUSHING OFFSHORE... EXCEPT PERHAPS FURTHER SOUTH INTO MENDOCINO COUNTY ON SUNDAY...WHICH MAY ALLOW FOR A SOUTHERLY INTRUSION OF MARINE AIR AND STRATUS. THIS WILL KEEP THE GRADIENT AT LEAST WEAKLY ONSHORE...SO KEPT TEMPS AT THE COAST FROM GETTING TOO WARM. EXPECT TEMPS SIMILAR TO THE LOW TO MID-60S WE SAW TODAY. THERE STILL SHOULD BE SOME MORNING CLOUDS AND FOG THAT MORNING AROUND HUMBOLDT BAY. BY SUNDAY INTO EARLY NEXT WEEK ANOTHER PUSH OF MARINE AIR WILL ARRIVE RESULTING IN GREATER COVERAGE AND INLAND PENETRATION OF STRATUS AND FOG. WITH THE GENERAL UPPER-LEVEL TROUGHING AND A DECENT SFC GRADIENT EXPECT THERE WILL BE ENOUGH MIXING TO CLEAR MOST LOCATIONS OUT EACH AFTERNOON. AAD && .AVIATION...SKIES HAVE FINALLY CLEARED OUT ALONG THE REDWOOD COAST. WINDS HAVE PICKED UP AT KCEC AS GRADIENT HAS TIGHTENED AND DAYTIME HEATING HAS MIXED THE LOWER ATMOSPHERE. WINDS THERE ARE PRESENTLY GUSTING OVER 25 KTS. HIGH UNCERTAINTY REGARDING LOW CLOUDS AND FOG LATER TONIGHT...PARTICULARLY AT KCEC. WINDS ARE FORECAST TO REMAIN STRONG AND NAM INDICATES FAIRLY STRONG LOW-LEVEL SUBSIDENCE. NAM...GFS..AND RUC FOG TOOLS ALL INDICATE POSSIBLE STRATUS DEVELOPMENT BUT LIMITED VSBY REDUCTION. HOWEVER...MOS INDICATE IFR VSBYS DEVELOPING AFTER MIDNIGHT. HAVE TAKEN THE MIDDLE GROUND AT KCEC WITH MVFR VSBYS AND BKN LOW CLOUD DECK LATER TONIGHT. BETTER CHANCES OF LOW CLOUDS AND/OR FOG AT KACV AS LOW-LEVEL MOISTURE POOLS ALONG THE COAST N OF CAPE MENDO AND LIGHTER WINDS ARE EXPECTED. VFR CONDITIONS EXPECTED AT KUKI OVERNIGHT. /SEC && .MARINE...A COUPLE OF SHIP REPORTS FROM AROUND THE AREA HINT THAT PRESENT WIND FORECAST IS ON TRACK TO PERHAPS A BIT HIGH. STRENGTHENING THERMAL TROF INLAND AND BUILDING HIGH OVER THE E PAC WILL TIGHTEN THE LOCAL PRESSURE GRADIENT WITH WINDS AND SEAS FOLLOWING SUIT. OFFSHORE GALE WARNING AND NEAR SHORE SMALL CRAFT ADVISORY REMAIN ON TRACK. ALTHO PROBABLY NOT A SLAM DUNK...SHOULD BE ENUF AREAL COVERAGE AND DURATION OF HAZARDOUS SEAS IN ZONE 450 TO WARRANT UPGRADING HAZARDOUS SEAS WATCH TO A WARNING. HAVE NOT MODIFIED START OR END TIMES OF THESE PRODUCTS. IT APPEARS WE ARE NEAR THE HEIGHT OF THE AMPLITUDE AND PERIOD OF SSW BACKGROUND SWELLS. WILL UPDATE THE EXISTING MWS FOR HAZARDOUS BREAKING WAVES ALONG S FACING HARBORS AND COVES AND EXTEND THRU TONIGHT. THIS PRODUCT MAY BE ABLE TO BE DISCONTINUED LATE TONIGHT OR DURING THE DAY SHIFT SAT. /SEC && .FIRE WEATHER...HOT WX WITH LOW RHS WILL CONTINUE THROUGH SAT AS UPPER RIDGE CROSSES THE DISTRICT. DESPITE TEMPS INTO THE 100S AND AFTERNOON RHS IN THE TEENS...WINDS WILL GENERALLY REMAIN LESS THAN 10 MPH AWAY FROM THE COAST, AND WILL BE MAINLY TERRAIN DRIVEN. AN UPPER LEVEL DISTURBANCE PASSING OVER NRN CA WILL BRING A SCHC OF TSTMS SUN AND COOLER...MORE MOIST AIR TO NW CA. MODELS REMAIN CONSISTENT WITH INCREASING MID LEVEL MOISTURE SUN...SO CONFIDENCE INCREASING REGARDING CONVECTION SUN. STORMS WILL BE HIGH BASED AND RELATIVELY DRY, HOWEVER WE CONTINUE TO THINK COVERAGE WILL BE TOO ISOLATED TO WARRANT A FIRE WX WATCH/WARNING FOR DRY LIGHTNING. AAD/BC && .EKA WATCHES/WARNINGS/ADVISORIES... CA...NONE. NORTHWEST CALIFORNIA COASTAL WATERS... SMALL CRAFT ADVISORY UNTIL 5 AM PDT MONDAY PZZ450-455. HAZARDOUS SEAS WARNING FROM 8 PM THIS EVENING TO 3 AM PDT MONDAY PZZ450. GALE WARNING UNTIL 11 PM PDT MONDAY PZZ470. GALE WARNING UNTIL 11 AM PDT MONDAY PZZ475. && $$ VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA FOLLOW US ON FACEBOOK AND TWITTER AT: HTTP://WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.EUREKA.GOV HTTP://WWW.TWITTER.COM/NWSEUREKA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
146 PM EDT SAT JUN 8 2013 .SYNOPSIS... WEAK HIGH PRESSURE BUILDS IN THROUGH SUNDAY. A WARM FRONT THEN SLOWLY APPROACHES FROM THE SOUTHWEST SUNDAY NIGHT AND MONDAY...LIFTING NORTH OF THE TRI-STATE FROM MONDAY NIGHT INTO EARLY TUESDAY MORNING. A COLD FRONT THEN SLOWLY CROSSES THE AREA THROUGH WEDNESDAY...THEN STALLS OUT JUST TO OUR SOUTH THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST RADAR TRENDS SHOW ISOLD -SHRA MOVING INTO SW PORTIONS OF THE CWA...WITH MORE NUMEROUS -SHRA BACK TOWARDS NE VA/E MD/DE AHEAD OF A SHORTWAVE STRETCHING FROM S CENTRAL NY INTO WESTERN VA PER LATEST WATER VAPOR IMAGERY. LATEST RUC/HRRR SUGGEST WESTERN/SOUTHERN ZONES WARRANT CHANCE POPS FOR SCT COVERAGE WITH ISOLD COVERAGE ELSEWHERE...SO HAVE UPDATED POPS ACCORDINGLY. RUC STILL SHOWS POTENTIAL FOR AROUND 1500 J/KG OF CAPE OVER INTERIOR ZONES THIS AFTERNOON AND A FEW HUNDRED J/KG OF CAPE ELSEWHERE...HAVE INCLUDED ISOLD TSTMS AS WELL. 35-45 KT OF BULK SHEAR WITH BULK RICHARDSON NUMBERS OF 15-40 OVER THE INTERIOR ALLOW FOR THE POSSIBILITY OF ONE OR TWO STRONG TO POSSIBLY SEVERE STORMS AS WELL...WITH GUSTY WINDS THE MAIN THREAT. ALSO WITH PRECIPITABLE WATERS FROM 1.25-1.5 INCHES PER 12Z SOUNDINGS...LOCALLY HEAVY RAINFALL CANNOT BE RULED OUT AS WELL. TEMPERATURES FORECAST GENERALLY ON TRACK...CONSISTENT WITH MIXING DOWN FROM 875 HPA...AND BLENDING WITH NAM AND HRRR 2-METER TEMPERATURES...6Z MAV...0Z MET...AND 0Z BIAS CORRECTED MOSGUIDE GUIDANCE. SHOULD SEE READINGS A FEW DEGREES ABOVE NORMAL...MAINLY UPPER 70S TO AROUND 80...BUT FROM AROUND 70 TO THE MID 70S NEAR THE COAST WITH AN AFTERNOON SEABREEZE. FOR THE HIGH SURF/RIP CURRENT THREAT...PLEASE REFER TO TIDES/COASTAL FLOODING SECTION OF THE AFD. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... BASED ON LATEST GUIDANCE HAVE ADDED A SLIGHT CHANCE OF -SHRA/TSRA EARLY THIS EVENING. OTHERWISE...WEAK HIGH PRES BUILDS THROUGH THE REGION TONIGHT THROUGH SUNDAY WITH DRY AND MILD CONDITIONS. LOWS TONIGHT WILL DROP INTO THE 60S IN/AROUND NYC AND IN THE MID TO UPPER 50S ELSEWHERE. HIGHS ON SUNDAY TOP OFF IN THE UPPER 70S TO LOWER 80S ONCE AGAIN. ANOTHER WEAK SHORTWAVE APPROACHES SUNDAY AFTERNOON...RESULTING IN ISOLATED SHOWERS AND THUNDERSTORMS ACROSS THE INTERIOR ONCE AGAIN IN THE AFTERNOON. WARM FRONT LIFTS INTO THE REGION SUNDAY NIGHT AS LOW PRES MOVES INTO THE GREAT LAKES. THIS LOW WILL SLOWLY MOVE INTO THE REGION THROUGH THE START OF THE NEW WORK WEEK...RESULTING IN A PROLONGED PERIOD OF UNSETTLED WEATHER. SCATTERED SHOWERS ARE POSSIBLE LATE SUNDAY NIGHT...AND THEN POPS RAMP UP TO LIKELY AS WARM FRONT LIFTS THROUGH THE REGION MONDAY AND UPPER TROUGH DIGS CLOSER TO THE EAST COAST. THE SYSTEM SLOWLY WORKS ITS WAY THROUGH THE REGION ON TUESDAY...AND PRECIP TAPERS OFF TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... CONTINUE MAINLY CHANCE POPS WEDNESDAY AS TROUGHING SETTLES INTO THE NE AND COLD FRONT SLOWLY PUSHES TO S WITH SLIGHT CHANCE OF THUNDER. THEN GO WITH SLIGHT CHANCE POPS WEDNESDAY NIGHT-FRIDAY WITH UPPER TROUGH OVER THE AREA. FOR TEMPERATURES MONDAY NIGHT-FRIDAY USED A BLEND OF MEX/MEX ENSEMBLE MEAN/ECE/WPC GUIDANCE. LOWS SHOULD RUN SLIGHTLY ABOVE NORMAL AND HIGHS NEAR NORMAL THROUGH THIS TIME FRAME. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... LOW PRESSURE CONTINUES TO DEPART. A BROAD SURFACE TROUGH WILL LINGER OVER THE REGION BEHIND THE LOW INTO LATE THIS EVENING. WEAK HIGH PRESSURE WILL THEN BUILD IN. GENERALLY LOOKING AT A WEST-SOUTHWEST FLOW BETWEEN 210-270. SPEEDS WILL BE AROUND 10 KT...WITH AN OCCASIONAL GUST INTO THE TEENS. A SEA BREEZE IS LIKELY TO DEVELOP AT THE COASTAL TERMINALS THIS AFTERNOON WITH THE WIND SHIFTING TO THE SOUTH BY LATE THIS AFTERNOON. AS OF NOW...DO NOT THINK THAT THE SEA BREEZE WILL GO THROUGH KLGA. LATE THIS EVENING THE WIND BECOMES LIGHT AND VARIABLE. WITH MAINLY CLEAR CONDITIONS AND THE LIGHT WIND WITH RESIDUAL MOISTURE SOME FOG IS POSSIBLE TOWARD SUNDAY SUNRISE...ALTHOUGH CONFIDENCE IS LOW AT THIS TIME. CIGS WILL GENERALLY REMAIN VFR OR MVFR THROUGH MID AFTERNOON...THEN VFR IS EXPECTED FROM LATE AFTERNOON THROUGH THE END OF THE TAF PERIOD. SOME ISOLATED-SCATTERED SHOWERS ARE POSSIBLE THIS AFTERNOON...MAINLY BETWEEN 19Z-22Z. .OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY... .SUNDAY AND SUNDAY NIGHT...VFR. .MONDAY-TUESDAY...SHOWERS/TSTMS WITH MVFR OR LOWER CONDITIONS LIKELY. .WEDNESDAY-THURSDAY...SHOWERS/TSTMS WITH MVFR CONDITIONS POSSIBLE. && .MARINE... MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK. OTHERWISE...SCA REMAINS UP FOR THE OCEAN AS SEAS WILL AVERAGE 6-10 FT TODAY AND WILL SLOWLY DIMINISH THROUGH LATE TONIGHT INTO SUNDAY MORNING. SCA ENDS OVER WESTERN OCEAN WATERS BY 6 AM SUNDAY AND FOR THE REST OF THE OCEAN WATERS...BY 11 AM SUNDAY. WINDS WILL BE 15 KT OR LESS OVER THE COASTAL OCEAN ZONES SUNDAY THROUGH WEDNESDAY AND 10 KT OR LESS OVER THE REMAINDER OF THE WATERS. SCA LEVEL SEAS COULD LINGER OVER THE EASTERN 2 COASTAL OCEAN ZONES INTO SUNDAY...THEN A PERSISTENT SOUTHERLY FLOW COUPLED WITH A DEVELOPING SOUTHERLY SWELL COULD RESULT IN SCA LEVEL SEAS RETURNING TO THE 2 EASTERN COASTAL OCEAN ZONES TUESDAY AND WEDNESDAY. && .HYDROLOGY... SCT-ISOLD SHRA/TSRA THIS AFTERNOON SHOULD PRODUCE MAINLY LESS THAN 1/4 OF AN INCH OF ADDITIONAL RAINFALL. HOWEVER WITH PRECIPITABLE WATERS RUNNING 1.25-1.5 INCHES...LOCALLY HEAVY RAINFALL IS POSSIBLE WITH ANY STRONGER CONVECTION. AREAS EXPERIENCING LOCALLY HEAVY RAINFALL LIKELY WILL EXPERIENCE AT LEAST MINOR URBAN/POOR DRAINAGE FLOODING. GIVEN RELATIVELY HIGHER LEVELS IN SMALL STREAMS...WILL ALSO HAVE TO MONITOR FOR FLOODING THERE IF LOCALLY HEAVY RAINFALL OCCURS. HACKENSACK RIVER ON BERGEN COUNTY REMAINS ABOVE THE MINOR FLOOD STAGE...AND SHOULD REMAIN ABOVE THROUGH MOST...IF NOT ALL THE AFTERNOON. ADDRESSING WITH AREAL FLOOD WARNING. 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. THERE IS THE POTENTIAL FOR 3/4 OF AN INCH TO 1 1/2 INCHES OF QPF...WITH LOCALLY HIGHER AMOUNTS...FROM LATE SUNDAY NIGHT INTO TUESDAY NIGHT. GIVEN RECENT RAINFALL...THIS WILL PRODUCE AT LEAST MINOR FLOODING OF POOR DRAINAGE/URBAN AREAS IN LOCATIONS RECEIVING LOCALLY HEAVY RAINFALL. && .TIDES/COASTAL FLOODING... BREAKING SURF WILL AVERAGE 6 TO 10 FT TODAY...RESULTING IN A HIGH RISK OF DANGEROUS RIP CURRENTS AT OCEAN BEACHES. MINOR BEACH EROSION IS LIKELY AS WELL. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH SURF ADVISORY UNTIL 9 PM EDT THIS EVENING FOR NYZ075-080- 081-178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR ANZ350-353. && $$ SYNOPSIS...MPS NEAR TERM...MALOIT/MPS SHORT TERM...MALOIT/MPS LONG TERM...MALOIT/MPS AVIATION...BC MARINE...MALOIT/MPS HYDROLOGY...MPS TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1235 PM EDT SAT JUN 8 2013 .SYNOPSIS... WEAK HIGH PRESSURE BUILDS IN THROUGH SUNDAY. A WARM FRONT THEN SLOWLY APPROACHES FROM THE SOUTHWEST SUNDAY NIGHT AND MONDAY...LIFTING NORTH OF THE TRI-STATE FROM MONDAY NIGHT INTO EARLY TUESDAY MORNING. A COLD FRONT THEN SLOWLY CROSSES THE AREA THROUGH WEDNESDAY...THEN STALLS OUT JUST TO OUR SOUTH THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST RADAR TRENDS SHOW ISOLD -SHRA MOVING INTO SW PORTIONS OF THE CWA...WITH MORE NUMEROUS -SHRA BACK TOWARDS NE VA/E MD/DE AHEAD OF A SHORTWAVE STRETCHING FROM S CENTRAL NY INTO WESTERN VA PER LATEST WATER VAPOR IMAGERY. LATEST RUC/HRRR SUGGEST WESTERN/SOUTHERN ZONES WARRANT CHANCE POPS FOR SCT COVERAGE WITH ISOLD COVERAGE ELSEWHERE...SO HAVE UPDATED POPS ACCORDINGLY. RUC STILL SHOWS POTENTIAL FOR AROUND 1500 J/KG OF CAPE OVER INTERIOR ZONES THIS AFTERNOON AND A FEW HUNDRED J/KG OF CAPE ELSEWHERE...HAVE INCLUDED ISOLD TSTMS AS WELL. 35-45 KT OF BULK SHEAR WITH BULK RICHARDSON NUMBERS OF 15-40 OVER THE INTERIOR ALLOW FOR THE POSSIBILITY OF ONE OR TWO STRONG TO POSSIBLY SEVERE STORMS AS WELL...WITH GUSTY WINDS THE MAIN THREAT. ALSO WITH PRECIPITABLE WATERS FROM 1.25-1.5 INCHES PER 12Z SOUNDINGS...LOCALLY HEAVY RAINFALL CANNOT BE RULED OUT AS WELL. TEMPERATURES FORECAST GENERALLY ON TRACK...CONSISTENT WITH MIXING DOWN FROM 875 HPA...AND BLENDING WITH NAM AND HRRR 2-METER TEMPERATURES...6Z MAV...0Z MET...AND 0Z BIAS CORRECTED MOSGUIDE GUIDANCE. SHOULD SEE READINGS A FEW DEGREES ABOVE NORMAL...MAINLY UPPER 70S TO AROUND 80...BUT FROM AROUND 70 TO THE MID 70S NEAR THE COAST WITH AN AFTERNOON SEABREEZE. FOR THE HIGH SURF/RIP CURRENT THREAT...PLEASE REFER TO TIDES/COASTAL FLOODING SECTION OF THE AFD. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... BASED ON LATEST GUIDANCE HAVE ADDED A SLIGHT CHANCE OF -SHRA/TSRA EARLY THIS EVENING. OTHERWISE...WEAK HIGH PRES BUILDS THROUGH THE REGION TONIGHT THROUGH SUNDAY WITH DRY AND MILD CONDITIONS. LOWS TONIGHT WILL DROP INTO THE 60S IN/AROUND NYC AND IN THE MID TO UPPER 50S ELSEWHERE. HIGHS ON SUNDAY TOP OFF IN THE UPPER 70S TO LOWER 80S ONCE AGAIN. ANOTHER WEAK SHORTWAVE APPROACHES SUNDAY AFTERNOON...RESULTING IN ISOLATED SHOWERS AND THUNDERSTORMS ACROSS THE INTERIOR ONCE AGAIN IN THE AFTERNOON. WARM FRONT LIFTS INTO THE REGION SUNDAY NIGHT AS LOW PRES MOVES INTO THE GREAT LAKES. THIS LOW WILL SLOWLY MOVE INTO THE REGION THROUGH THE START OF THE NEW WORK WEEK...RESULTING IN A PROLONGED PERIOD OF UNSETTLED WEATHER. SCATTERED SHOWERS ARE POSSIBLE LATE SUNDAY NIGHT...AND THEN POPS RAMP UP TO LIKELY AS WARM FRONT LIFTS THROUGH THE REGION MONDAY AND UPPER TROUGH DIGS CLOSER TO THE EAST COAST. THE SYSTEM SLOWLY WORKS ITS WAY THROUGH THE REGION ON TUESDAY...AND PRECIP TAPERS OFF TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... CONTINUE MAINLY CHANCE POPS WEDNESDAY AS TROUGHING SETTLES INTO THE NE AND COLD FRONT SLOWLY PUSHES TO S WITH SLIGHT CHANCE OF THUNDER. THEN GO WITH SLIGHT CHANCE POPS WEDNESDAY NIGHT-FRIDAY WITH UPPER TROUGH OVER THE AREA. FOR TEMPERATURES MONDAY NIGHT-FRIDAY USED A BLEND OF MEX/MEX ENSEMBLE MEAN/ECE/WPC GUIDANCE. LOWS SHOULD RUN SLIGHTLY ABOVE NORMAL AND HIGHS NEAR NORMAL THROUGH THIS TIME FRAME. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... LOW PRESSURE CONTINUES TO MOVE RAPIDLY TO THE NORTHEAST THIS MORNING. A BROAD SURFACE TROUGH WILL LINGER OVER THE REGION BEHIND THE LOW...INTO LATE THIS EVENING. WEAK HIGH PRESSURE WILL THEN BUILD IN. GENERALLY LOOKING AT A WEST-NORTHWEST WIND THIS MORNING. WINDS WILL BE ANYWHERE FROM 280-310. SPEEDS WILL BE AROUND 10 KT...WITH AN OCCASIONAL GUST INTO THE TEENS. A SEA BREEZE IS LIKELY TO DEVELOP AT KJFK THIS AFTERNOON WITH THE WIND SHIFTING TO THE SOUTHWEST AND THEN SOUTH BY LATE THIS AFTERNOON. AS OF NOW...DO NOT THINK THAT THE SEA BREEZE WILL GO THROUGH KLGA. LATE THIS EVENING THE WIND BECOMES LIGHT AND VARIABLE. WITH MAINLY CLEAR CONDITIONS AND THE LIGHT WIND WITH RESIDUAL MOISTURE SOME FOG IS POSSIBLE TOWARD SUNDAY SUNRISE...ALTHOUGH CONFIDENCE IS LOW AT THIS TIME. CIGS WILL GENERALLY REMAIN MVFR THROUGH MUCH OF THE LATE MORNING AND FIRST HALF OF THE AFTERNOON. THEN VFR IS EXPECTED FROM LATE AFTERNOON THROUGH THE END OF THE TAF PERIOD. ISOLATED SHOWERS ARE POSSIBLE THIS AFTERNOON. .OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY... .SUNDAY AND SUNDAY NIGHT...VFR. .MONDAY-TUESDAY...SHOWERS/TSTMS WITH MVFR OR LOWER CONDITIONS LIKELY. .WEDNESDAY...SHOWERS/TSTMS WITH MVFR CONDITIONS POSSIBLE. && .MARINE... MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK. OTHERWISE...SCA REMAINS UP FOR THE OCEAN AS SEAS WILL AVERAGE 6-10 FT TODAY AND WILL SLOWLY DIMINISH THROUGH LATE TONIGHT INTO SUNDAY MORNING. SCA ENDS OVER WESTERN OCEAN WATERS BY 6 AM SUNDAY AND FOR THE REST OF THE OCEAN WATERS...BY 11 AM SUNDAY. WINDS WILL BE 15 KT OR LESS OVER THE COASTAL OCEAN ZONES SUNDAY THROUGH WEDNESDAY AND 10 KT OR LESS OVER THE REMAINDER OF THE WATERS. SCA LEVEL SEAS COULD LINGER OVER THE EASTERN 2 COASTAL OCEAN ZONES INTO SUNDAY...THEN A PERSISTENT SOUTHERLY FLOW COUPLED WITH A DEVELOPING SOUTHERLY SWELL COULD RESULT IN SCA LEVEL SEAS RETURNING TO THE 2 EASTERN COASTAL OCEAN ZONES TUESDAY AND WEDNESDAY. && .HYDROLOGY... SCT-ISOLD SHRA/TSRA THIS AFTERNOON SHOULD PRODUCE MAINLY LESS THAN 1/4 OF AN INCH OF ADDITIONAL RAINFALL. HOWEVER WITH PRECIPITABLE WATERS RUNNING 1.25-1.5 INCHES...LOCALLY HEAVY RAINFALL IS POSSIBLE WITH ANY STRONGER CONVECTION. AREAS EXPERIENCING LOCALLY HEAVY RAINFALL LIKELY WILL EXPERIENCE AT LEAST MINOR URBAN/POOR DRAINAGE FLOODING. GIVEN RELATIVELY HIGHER LEVELS IN SMALL STREAMS...WILL ALSO HAVE TO MONITOR FOR FLOODING THERE IF LOCALLY HEAVY RAINFALL OCCURS. HACKENSACK RIVER ON BERGEN COUNTY REMAINS ABOVE THE MINOR FLOOD STAGE...AND SHOULD REMAIN ABOVE THROUGH MOST...IF NOT ALL THE AFTERNOON. ADDRESSING WITH AREAL FLOOD WARNING. 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. THERE IS THE POTENTIAL FOR 3/4 OF AN INCH TO 1 1/2 INCHES OF QPF...WITH LOCALLY HIGHER AMOUNTS...FROM LATE SUNDAY NIGHT INTO TUESDAY NIGHT. GIVEN RECENT RAINFALL...THIS WILL PRODUCE AT LEAST MINOR FLOODING OF POOR DRAINAGE/URBAN AREAS IN LOCATIONS RECEIVING LOCALLY HEAVY RAINFALL. && .TIDES/COASTAL FLOODING... BREAKING SURF WILL AVERAGE 6 TO 10 FT TODAY...RESULTING IN A HIGH RISK OF DANGEROUS RIP CURRENTS AT OCEAN BEACHES. MINOR BEACH EROSION IS LIKELY AS WELL. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH SURF ADVISORY UNTIL 9 PM EDT THIS EVENING FOR NYZ075-080- 081-178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR ANZ350-353. && $$ SYNOPSIS...MPS NEAR TERM...MALOIT/MPS SHORT TERM...MALOIT/MPS LONG TERM...MALOIT/MPS AVIATION...BC MARINE...MALOIT/MPS HYDROLOGY...MPS TIDES/COASTAL FLOODING...MPS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1059 AM EDT SAT JUN 8 2013 .SYNOPSIS... WEAK HIGH PRESSURE BUILDS IN THROUGH SUNDAY. A WARM FRONT THEN SLOWLY APPROACHES FROM THE SOUTHWEST SUNDAY NIGHT AND MONDAY...LIFTING NORTH OF THE TRI-STATE FROM MONDAY NIGHT INTO EARLY TUESDAY MORNING. A COLD FRONT THEN SLOWLY CROSSES THE AREA THROUGH WEDNESDAY...THEN STALLS OUT JUST TO OUR SOUTH THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST RADAR TRENDS SHOW ISOLD -SHRA MOVING INTO SOUTHERN NJ...WITH MORE NUMEROUS -SHRA BACK TOWARDS BWI/DCA AHEAD OF A SHORTWAVE TROUGH EVIDENT IN WATER VAPOR OVER THE CENTRAL APPALACHIANS. LATEST RUC/NAM/HRRR/SREF SUGGEST ENTIRE AREA WARRANTS AT LEAST SLIGHT CHANCE POPS FOR REMAINDER OF DAY. WITH RUC SHOWING POTENTIAL FOR 1000-1500 J/KG OF CAPE OVER INTERIOR ZONES THIS AFTERNOON AND A FEW HUNDRED J/KG OF CAPE ELSEWHERE...HAVE INCLUDED ISOLD TSTMS AS WELL. 35-45 KT OF BULK SHEAR WITH BULK RICHARDSON NUMBERS OF 15-40 OVER THE INTERIOR ALLOW FOR THE POSSIBILITY OF ONE OR TWO STRONG TO POSSIBLY SEVERE STORMS AS WELL...WITH GUSTY WINDS THE MAIN THREAT. ALSO WITH PRECIPITABLE WATERS FROM 1.25-1.5 INCHES PER 12Z SOUNDINGS...LOCALLY HEAVY RAINFALL CANNOT BE RULED OUT AS WELL. TEMPERATURES FORECAST GENERALLY ON TRACK...CONSISTENT WITH MIXING DOWN FROM 875 HPA...AND BLENDING WITH NAM AND HRRR 2-METER TEMPERATURES...6Z MAV...0Z MET...AND 0Z BIAS CORRECTED MOSGUIDE GUIDANCE. SHOULD SEE READINGS A FEW DEGREES ABOVE NORMAL...MAINLY UPPER 70S TO AROUND 80...BUT FROM AROUND 70 TO THE MID 70S NEAR THE COAST WITH AN AFTERNOON SEABREEZE. FOR THE HIGH SURF/RIP CURRENT THREAT...PLEASE REFER TO TIDES/COASTAL FLOODING SECTION OF THE AFD. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... BASED ON LATEST GUIDANCE HAVE ADDED A SLIGHT CHANCE OF -SHRA/TSRA EARLY THIS EVENING. OTHERWISE...WEAK HIGH PRES BUILDS THROUGH THE REGION TONIGHT THROUGH SUNDAY WITH DRY AND MILD CONDITIONS. LOWS TONIGHT WILL DROP INTO THE 60S IN/AROUND NYC AND IN THE MID TO UPPER 50S ELSEWHERE. HIGHS ON SUNDAY TOP OFF IN THE UPPER 70S TO LOWER 80S ONCE AGAIN. ANOTHER WEAK SHORTWAVE APPROACHES SUNDAY AFTERNOON...RESULTING IN ISOLATED SHOWERS AND THUNDERSTORMS ACROSS THE INTERIOR ONCE AGAIN IN THE AFTERNOON. WARM FRONT LIFTS INTO THE REGION SUNDAY NIGHT AS LOW PRES MOVES INTO THE GREAT LAKES. THIS LOW WILL SLOWLY MOVE INTO THE REGION THROUGH THE START OF THE NEW WORK WEEK...RESULTING IN A PROLONGED PERIOD OF UNSETTLED WEATHER. SCATTERED SHOWERS ARE POSSIBLE LATE SUNDAY NIGHT...AND THEN POPS RAMP UP TO LIKELY AS WARM FRONT LIFTS THROUGH THE REGION MONDAY AND UPPER TROUGH DIGS CLOSER TO THE EAST COAST. THE SYSTEM SLOWLY WORKS ITS WAY THROUGH THE REGION ON TUESDAY...AND PRECIP TAPERS OFF TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... CONTINUE MAINLY CHANCE POPS WEDNESDAY AS TROUGHING SETTLES INTO THE NE AND COLD FRONT SLOWLY PUSHES TO S WITH SLIGHT CHANCE OF THUNDER. THEN GO WITH SLIGHT CHANCE POPS WEDNESDAY NIGHT-FRIDAY WITH UPPER TROUGH OVER THE AREA. FOR TEMPERATURES MONDAY NIGHT-FRIDAY USED A BLEND OF MEX/MEX ENSEMBLE MEAN/ECE/WPC GUIDANCE. LOWS SHOULD RUN SLIGHTLY ABOVE NORMAL AND HIGHS NEAR NORMAL THROUGH THIS TIME FRAME. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... LOW PRESSURE CONTINUES TO MOVE RAPIDLY TO THE NORTHEAST THIS MORNING. A BROAD SURFACE TROUGH WILL LINGER OVER THE REGION BEHIND THE LOW...INTO LATE THIS EVENING. WEAK HIGH PRESSURE WILL THEN BUILD IN. GENERALLY LOOKING AT A WEST-NORTHWEST WIND THIS MORNING. WINDS WILL BE ANYWHERE FROM 280-310. SPEEDS WILL BE AROUND 10 KT...WITH AN OCCASIONAL GUST INTO THE TEENS. A SEA BREEZE IS LIKELY TO DEVELOP AT KJFK THIS AFTERNOON WITH THE WIND SHIFTING TO THE SOUTHWEST AND THEN SOUTH BY LATE THIS AFTERNOON. AS OF NOW...DO NOT THINK THAT THE SEA BREEZE WILL GO THROUGH KLGA. LATE THIS EVENING THE WIND BECOMES LIGHT AND VARIABLE. WITH MAINLY CLEAR CONDITIONS AND THE LIGHT WIND WITH RESIDUAL MOISTURE SOME FOG IS POSSIBLE TOWARD SUNDAY SUNRISE...ALTHOUGH CONFIDENCE IS LOW AT THIS TIME. CIGS WILL GENERALLY REMAIN MVFR THROUGH MUCH OF THE LATE MORNING AND FIRST HALF OF THE AFTERNOON. THEN VFR IS EXPECTED FROM LATE AFTERNOON THROUGH THE END OF THE TAF PERIOD. ISOLATED SHOWERS ARE POSSIBLE THIS AFTERNOON. .OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY... .SUNDAY AND SUNDAY NIGHT...VFR. .MONDAY-TUESDAY...SHOWERS/TSTMS WITH MVFR OR LOWER CONDITIONS LIKELY. .WEDNESDAY...SHOWERS/TSTMS WITH MVFR CONDITIONS POSSIBLE. && .MARINE... MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. OTHER THAN ADDING ISOLD TSTMS IN THIS AFTERNOON/EARLY EVENING...FORECAST APPEARS ON TRACK. OTHERWISE...SCA REMAINS UP FOR THE OCEAN AS SEAS WILL AVERAGE 6-10 FT TODAY AND WILL SLOWLY DIMINISH THROUGH LATE TONIGHT INTO SUNDAY MORNING. SCA ENDS OVER WESTERN OCEAN WATERS BY 6 AM SUNDAY AND FOR THE REST OF THE OCEAN WATERS...BY 11 AM SUNDAY. WINDS WILL BE 15 KT OR LESS OVER THE COASTAL OCEAN ZONES SUNDAY THROUGH WEDNESDAY AND 10 KT OR LESS OVER THE REMAINDER OF THE WATERS. SCA LEVEL SEAS COULD LINGER OVER THE EASTERN 2 COASTAL OCEAN ZONES INTO SUNDAY...THEN A PERSISTENT SOUTHERLY FLOW COUPLED WITH A DEVELOPING SOUTHERLY SWELL COULD RESULT IN SCA LEVEL SEAS RETURNING TO THE 2 EASTERN COASTAL OCEAN ZONES TUESDAY AND WEDNESDAY. && .HYDROLOGY... THERE WILL STILL BE AREAS WHERE WATER HAS PONDED...AND THE SMALLER RIVERS AND STREAMS WILL CONTINUE TO RECEDE THIS MORNING. MAIN STEM RIVERS WILL CONTINUE TO RISE TODAY DUE TO RUNOFF...BUT ARE EXPECTED TO REMAIN BELOW BANKFULL. 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. THERE IS THE POTENTIAL FOR 3/4 OF AN INCH TO 1 1/2 INCHES OF QPF...WITH LOCALLY HIGHER AMOUNTS...FROM LATE SUNDAY NIGHT INTO TUESDAY NIGHT. GIVEN RECENT RAINFALL...THIS WILL PRODUCE AT LEAST MINOR FLOODING OF POOR DRAINAGE/URBAN AREAS IN LOCATIONS RECEIVING LOCALLY HEAVY RAINFALL. && .TIDES/COASTAL FLOODING... BREAKING SURF WILL AVERAGE 6 TO 10 FT TODAY...RESULTING IN A HIGH RISK OF DANGEROUS RIP CURRENTS AT OCEAN BEACHES. MINOR BEACH EROSION IS LIKELY AS WELL. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH SURF ADVISORY UNTIL 9 PM EDT THIS EVENING FOR NYZ075-080- 081-178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR ANZ350-353. && $$ SYNOPSIS...MPS NEAR TERM...MALOIT/MPS SHORT TERM...MALOIT/MPS LONG TERM...MALOIT/MPS AVIATION...BC/MET MARINE...MALOIT/MPS HYDROLOGY...MPS TIDES/COASTAL FLOODING...MPS
AREA FORECAST DISCUSSION
NWS MIAMI FL
1018 PM EDT SUN JUN 9 2013 .UPDATE...NO MAJOR CHANGES TO THE FORECAST. HRRR SHOWS SHOWERS DEVELOPING OVER THE ATLANTIC AFTER 3 AM, THEN MOVING ONSHORE THE ATLANTIC COAST STARTING AT 5 AM. KEPT ISOLATED SHOWERS IN THE FORECAST FOR THE EAST COAST METRO AREAS EVEN THOUGH NONE ARE CURRENTLY PRESENT ON RADAR. HRRR WOULD SUGGEST SLIGHTLY HIGHER POP TOWARDS DAWN, BUT UNCERTAINTIES PRECLUDE INCREASING POPS AT THIS TIME. A TYPICALLY MUGGY NIGHT WITH LOWS IN THE 70S ARE EXPECTED. /GREGORIA && .PREV DISCUSSION... /ISSUED 754 PM EDT SUN JUN 9 2013/ AVIATION... FOR THE VERY SHORT TERM...TERMINAL KAPF HAS SHOWERS THAT COULD IMPACT THE TERMINAL FOR THE NEXT HALF HOUR TO HOUR WITH VERY BRIEF IFR CONDITIONS POSSIBLE AS THE SHOWERS PASS. AN ISOLATED LIGHTNING STRIKE IS POSSIBLE. OTHERWISE...MAINLY VFR CONDITIONS EXPECTED FOR MOST OF THE EAST COAST TERMINALS THROUGH THE EVENING HOURS. TERMINAL KTMB COULD BE IMPACTED BY A FEW SHOWERS WITHIN THE NEXT HOUR WITH BRIEF PERIODS OF MVFR CONDITIONS POSSIBLE AS THE SHOWERS PASS WITH AN ISOLATED LIGHTNING STRIKE POSSIBLE. 60 PREV DISCUSSION... /ISSUED 257 PM EDT SUN JUN 9 2013/ DISCUSSION... DESPITE SLIGHTLY DRIER AIR ACROSS THE AREA TODAY, A FEW HEAVY SHOWERS HAVE DEVELOPED OVER THE ATLANTIC WATERS AND ARE MOVING ONSHORE THE SOUTHEAST FLORIDA COAST, AS WELL AS DEVELOPING OVER THE WESTERN HALF OF THE PENINSULA. WHILE THE ACTIVITY OVER THE WESTERN AREAS WAS EXPECTED, THE SHOWERS MOVING ONSHORE THE EAST COAST IS NOT WHAT WE TYPICALLY SEE DURING THE AFTERNOON HOURS WHEN EASTERLY WINDS TEND TO SHIFT MOST OF THE CONVECTION OVER THE INTERIOR AND WEST. NEVERTHELESS, TRENDS DICTATE THAT WE KEEP IN ISOLATED SHOWERS FOR THE EAST COAST AND SCATTERED TSTMS FOR INTERIOR AND WEST THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING. SUBTROPICAL HIGH EXTENDING FROM THE ATLANTIC ACROSS THE FLORIDA PENINSULA WILL CONTROL OUR WEATHER THROUGH TUESDAY. THIS WILL RESULT IN CONTINUED EASTERLY WIND FLOW, ALTHOUGH GRADUALLY DECREASING AS WE GET TO TUESDAY. THE EASTERLY FLOW WILL FAVOR THE GREATEST CONCENTRATION OF SHOWERS AND THUNDERSTORMS OVER THE INTERIOR AND WEST, WITH ISOLATED SHOWERS EAST COAST METRO. DIDN`T DEPART MUCH FROM PREVIOUS FORECAST WHICH IS MORE IN LINE WITH THE LOWER POPS DEPICTED IN THE NAM-BASED MOS VERSUS THE HIGHER GFS- BASED MOS. THE RIDGE BEGINS TO BREAK DOWN ON TUESDAY WITH LIGHTER WINDS AND STEERING FLOW TENDING TO FAVOR A WIDER DISTRIBUTION OF CONVECTION ACROSS THE SOUTHERN PENINSULA, ESPECIALLY DURING THE DIURNALLY-FAVORED AFTERNOON HOURS. BY WEDNESDAY, MODELS DEPICT A WEAK MID-LEVEL TROUGH OVER SOUTH FLORIDA, WITH THE GFS STRONGEST IN TRYING TO CLOSE OFF A WEAK LOW. THIS WILL RESULT IN GREATER OVERALL COVERAGE OF SCATTERED THUNDERSTORMS ACROSS THE AREA. SOME OF THE STORMS COULD GET STRONG BOTH TUESDAY AND WEDNESDAY AFTERNOONS AS MID-LEVELS COOL IN ASSOCIATION WITH THE WEAKENING RIDGE AND THE MID-LEVEL LOW/TROUGH SETTING UP OVER THE AREA. MAIN IMPACTS FROM THESE STORMS WOULD BE STRONG WIND GUSTS AND HAIL, IF THE INSTABILITY MATERIALIZES AS MODELS SUGGEST. LOOKING LONG-RANGE...NOT MUCH CHANGE AS THE MID/UPPER LEVEL TROUGH IS EXPECTED OVER THE AREA WHICH WILL LEAD TO SCATTERED AFTERNOON STORMS MOST AREAS EXCEPT PERHAPS LESS COVERAGE ALONG THE GULF COAST. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR TO SLIGHTLY ABOVE JUNE NORMALS WITH LOWS IN THE 70S AND HIGHS RANGING FROM THE UPPER 80S ALONG THE EAST COAST TO THE 90S INTERIOR AND WEST. AVIATION... DRIER AIRMASS IN PLACE OVER SOUTH FLORIDA TODAY AND TONIGHT...LEADING TO ISOLATED TO SCATTERED SHOWER OR TSTM COVERAGE. POPS STILL AS HIGH AS 30 PERCENT AT SOME TERMINALS...BUT CONFIDENCE IN ACTIVITY IS TOO LOW TO WARRANT INCLUSION IN TAFS WITH THE EXCEPTION OF APF. VFR CONDITIONS WILL PREVAIL...WITH DIURNAL BUILDUP AS CU PERHAPS CAUSING A FEW HOURS OF CIGS THIS AFTERNOON AND EARLY EVENING. BEST CHANCE OF MVFR CIGS OR VIS WITH ANY TSTM FOR THIS AFTERNOON AND EVENING WILL BE AT APF. ESE WINDS 10 TO 15 KTS THIS AFTERNOON AND EARLY EVENING EAST COAST BECOMING 5-10 OVERNIGHT AND THROUGH TOMORROW MORNING. APF WILL HAVE A SSW SEA BREEZE OF 5 TO 10 KNOTS THIS AFTERNOON WITH WINDS TURNING MORE EASTERLY AT 5 TO 10 KNOTS AFTER SUNSET AND THROUGH TOMORROW MORNING. MARINE... E/SE WINDS AROUND 15 KNOTS ATLANTIC WATERS AND 10-15 KNOTS GULF WATERS AND LAKE OKEECHOBEE WILL CONTINUE THROUGH MONDAY, WITH A GRADUAL DECREASE TUESDAY AND WEDNESDAY AS WINDS BECOME MORE SE. SEAS WILL REMAIN NO MORE THAN 4-5 FT AND NO HEADLINES/CAUTIONARY STATEMENTS ANTICIPATED. FIRE WEATHER... RELATIVE HUMIDITY VALUES WILL REMAIN SEASONABLY HIGH THROUGH THE PERIOD WITH SCATTERED MAINLY AFTERNOON STORMS. COULD BE SOME ISOLATED SPOTS WITH LIGHT FOG OVER THE NEXT FEW NIGHTS, BUT CONDITIONS NOT CONDUCIVE FOR WIDESPREAD REDUCTIONS IN VISIBILITY. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 77 88 76 89 / 10 10 10 20 FORT LAUDERDALE 79 88 77 88 / 10 10 10 20 MIAMI 78 89 76 89 / 10 10 10 20 NAPLES 74 90 74 89 / - 30 20 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
845 PM EDT Sun Jun 9 2013 .NEAR TERM [Tonight]... The large scale longwave pattern remains amplified, highlighted by ridging over west half, a trough Ewd to east coast with axis approaching MS River, and a ridge over extreme Wrn Atlc. Series of H5 impulses continue to ride across base of trough Newd across Srn MS into Cntrl AL advecting ample moisture Newd. At surface, high well off mid-Atlc coast with stnry front Swwd across Cntrl GA then Wwd across SE GA. Subtropical ridge W-E across Nrn FL Peninsula. During Sun aftn into eve, very slow moving MCS developed offshore of extreme Wrn Panhandle waters and aided by 30-40kt H5 flow from one of the impulses moved N-NE around 25 mph towards SE AL and adjacent SW GA. Higher winds did mix down into the stronger storms generating special marine warnings over our Panhandle waters and a severe thunderstorm across portions of Holmes, Walton and Washington counties. Several outflows ahead of MCS may have knocked down a few trees. By early eve, the MCS had weakened some and remained over the western waters and coastal portions of Walton and Bay counties. EVX radar estimated 3-3.5 inches STP over southern Walton county. Our flash flood guidance remains very high. Still will monitor in case localized flooding occurs. For the rest of tonight, the combination of passing H5 impulse and ample moisture advected Newd as reflected in TAE RAP soundings with 1.70 PWAT, and remnant of MCS will continue to generate storms, although chances noticeably decrease over the SE half of CWA away from impulses and MCS influence. However some rain from Wrn extent of east coast sea breeze may impact portions of SE Big Bend. Will go with 50-30% NW-SE POP gradient thru 06z then 40-0% after 06z. Lows tonight will be in the low 70s. There is some potential for fog tonight, especially where rains linger. NARRE focuses fog and low clouds west half in areas of highest residual moisture and will input into GRIDS. && .SHORT TERM [Monday through Tuesday]... With ample deep layer moisture, CAPE, and Q-G forcing (associated with the passage of a 500mb trough), we are forecasting above-climo PoPs for Monday (50-60%). The trough will be east of our forecast area Tuesday, so any forcing for deep moist convection will have to come from the mesoscale (usually the sea breeze fronts). With deep layer northwest flow, the sea breeze front will likely get pinned near the coast, which is where our highest PoP will be (about 30%). This PoP is slightly below climo, mainly due to the expected decrease in deep layer moisture. && .LONG TERM [Wednesday through next Sunday]... The GFS and ECMWF are in good agreement as they forecast the Southeast to be under northwest flow aloft through Friday, as a long wave trough develops along the U.S. east coast. The day-to-day details will be difficult to forecast, as both solutions differ on the timing of minor short waves "diving down" into our forecast area. This far out it`s nearly impossible to time these disturbances, so we will carry near-climo PoPs until Friday, then worry about fine-tuning as the week goes on. Sometimes these disturbances can move through overnight, and sometimes they can be associated with an enhanced threat of organized strong/severe storms (night or day), including damaging winds. Ironically, the GFS and ECMWF are in excellent agreement in their timing of a "backdoor" cold front moving through our region on Friday. Friday`s PoP will be above climo due to this front. Slightly lower PoPs are forecast for next weekend as a drier airmass moves into the region. && .AVIATION...[Through 00Z Tuesday] An area of rain with isolated TSRA currently pushing through the panhandle and SE AL this evening will gradually weaken as it enters SW Georgia and the western Big Bend. Went with convective tempo groups at ECP and TLH to account for this activity. Later this evening and overnight, lower clouds or patchy fog could develop as winds decrease, especially from 09-13Z. VFR conditions should resume after 13Z as the fog/lower clouds lift with another round of showers and thunderstorms late Monday morning and afternoon. && .MARINE... Rain with embedded isold Tstms and gusty winds assocd with very slow moving MCS will impact wrn waters at least until midnight. Divided wrn and ern waters to account for this. Otherwise, winds and seas are expected to gradually decrease overnight and Monday as the trough (currently near the Gulf Coast) moves inland and weakens. Winds and seas are likely to remain below exercise caution levels for the next several days. && .FIRE WEATHER... Relative humidities will remain above critical thresholds throughout the period, as the typical summertime pattern of daily chances of showers and thunderstorms continues through the next several days. && .HYDROLOGY... Area rivers remain below action stage. The WPC QPF total for the next 5 days is 1 to 2 inches (much of which will occur today and Monday), but isolated amounts could be much higher than this. The localized nature of this heavy rain potential precludes the need for any type of flood watch. The most vulnerable locations, as usual, are urban environments, where even short durations of high rain rates can cause flooding. The greatest threat for high QPF is today and Monday, as precip water values will be above climo. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 71 89 71 93 73 / 20 50 30 30 20 Panama City 75 85 74 88 76 / 40 50 20 30 20 Dothan 71 89 71 95 74 / 50 50 20 20 20 Albany 71 89 71 94 74 / 40 50 20 20 20 Valdosta 70 90 70 95 71 / 30 60 30 20 20 Cross City 71 88 70 90 71 / 20 40 30 30 20 Apalachicola 75 84 74 87 75 / 20 30 20 30 20 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ NEAR TERM...Block SHORT TERM...Fournier LONG TERM...Fournier AVIATION...Barry MARINE...Block FIRE WEATHER...Lahr/Block HYDROLOGY...Fournier
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
220 PM EDT SAT JUN 8 2013 .SHORT TERM...SHOWERS AND STORMS ARE CURRENTLY HAVING A TOUGH TIME DEVELOPING GIVEN A LITTLE CIN AROUND 850 TO 700 MB AND DRY AIR ALOFT. RAP SOUNDING SHOWS PWAT NEAR 1.45 INCHES NEAR JAX INDICATING THE DRYNESS IN THE MID AND UPPER LEVELS. STILL...WE EXPECT THAT ISOLD TO SCT SHOWERS AND STORMS WILL DEVELOP WITH THE BEST FOCUS OF ACTIVITY OVER NE FL WHERE SEA BREEZE MERGERS ARE MORE LIKELY. UPPER LEVELS SHOW SOMEWHAT FAVORABLE DIVERGENCE OVER PARTS OF NE FL WITH THE REGION IN THE RRQ OF A 50-60 KT JET. LIKE WAS MENTIONED IN EARLIER DISCUSSION...THE DRY AIR ALOFT WILL SERVE TO ENHANCE ANY DOWNBURSTS...SO THAT WILL CONTINUE TO BE A CONCERN FOR REST OF TODAY AND EARLY THIS EVENING. SUNDAY/SUNDAY NIGHT...CONTINUED GOOD AGREEMENT AMONG MODELS ON DEEP TROPICAL MOISTURE RETURNING TO THE AREA AS SHORT WAVE ENERGY MOVES IN FROM THE GULF. WILL MOST LIKELY HAVE AN ONSET OF NUMEROUS SHOWERS/STORMS BY EARLY AFTERNOON AS THE SHORT WAVE INTERACTS WITH AN ACTIVE WEST COAST SEABREEZE AND DIFFERENTIAL HEATING. STORMS MAY LINGER ALONG THE EAST COAST DURING THE EARLY EVENING FROM WEST/EAST COAST SEABREEZE MERGER. GIVEN HIGH PWAT (2+ INCHES) AND INSTABILITY (CAPES 2500-3000J) A FEW STORMS COULD GET STRONG WITH FREQUENT CLOUD TO GROUND LIGHTNING...LOCALLY HEAVY RAIN...AND GUSTY WINDS. CLOUD COVER AND AND HIGHER PRECIP COVERAGE WILL HELP KEEP HIGH TEMPERATURES UNDER CHECK SUNDAY AND WILL BE SLIGHTLY BELOW NORMAL...WITH WARM/HUMID CONDITIONS SUNDAY NIGHT. .LONG TERM /MONDAY THROUGH SATURDAY/... A SHORTWAVE TROUGH WILL PROGRESS EASTWARD FROM THE GREAT LAKES STATES EARLY ON MON INTO NEW ENGLAND BY LATE TUES. THIS FEATURE WILL PUSH THE AXIS OF ATLANTIC RIDGING INTO THE FL PENINSULA BY TUES...WHICH WILL KEEP MEAN LAYER SOUTHWEST TO WEST FLOW IN PLACE LOCALLY. DEEP TROPICAL MOISTURE AND MESOSCALE BOUNDARY COLLISIONS WILL RESULT IN NUMEROUS SHOWERS AND THUNDERSTORMS ALONG THE INTERSTATE 95 CORRIDOR ON MON...WITH SCATTERED ACTIVITY EXPECTED ELSEWHERE. ABUNDANT MID AND HIGH ALTITUDE CLOUDINESS AND RAINFALL SHOULD KEEP HIGHS AROUND OR JUST SLIGHTLY BELOW CLIMO ON MON...WITH HIGHS GENERALLY IN THE UPPER 80S. CLOUDS AND DEWPOINTS IN THE 70S WILL KEEP LOWS GENERALLY IN THE 70-75 DEGREE RANGE. MOISTURE LEVELS SLOWLY DECREASE ON TUES...BUT FORCING FROM A WEAK BOUNDARY SINKING INTO OUR AREA SHOULD PROMOTE SCATTERED DIURNAL CONVECTIVE COVERAGE. LESS MORNING CLOUD COVER WILL ALLOW HIGHS ON TUES TO CLIMB INTO THE LOWER 90S...WITH UPPER 80S AT THE COAST. ACTIVITY ALONG A WEAK SOUTHWARD MOVING BOUNDARY MAY CONTINUE INTO THE EVENING HOURS ON TUES IN NORTHEAST FL. LOWS WILL AGAIN ONLY FALL TO THE 70-75 RANGE. LONG-TERM GUIDANCE INDICATES THAT RIDGING WILL BUILD OVER THE PLAINS STATES BY MIDWEEK. THIS WILL CHANGE OUR FLOW ALOFT LOCALLY TO NORTHWEST TO NORTHERLY...WHICH WILL ADVECT DRIER AIR ALOFT INTO OUR REGION. THE AXIS OF ATLANTIC RIDGING WILL BE DISPLACED OVER SOUTH FL...AND A WESTERLY STEERING FLOW SHOULD FOCUS WIDELY SCATTERED DIURNAL CONVECTION ALONG THE I-95 CORRIDOR...WITH ONLY ISOLATED POPS EXPECTED ACROSS INTERIOR SOUTHEAST GA. LESS CLOUD COVER AND RAINFALL COVERAGE WILL ALLOW HIGHS TO CLIMB INTO THE MID 90S INLAND AND NEAR 90 AT THE COAST ON WED AND THURS. TROUGHING MAY STRENGTHEN ENOUGH ALONG THE EASTERN SEABOARD ON FRI TO BRING A LATE SEASON COLD FRONT SOUTHWARD INTO OUR REGION. THE FRONT WILL STALL JUST SOUTH OF THE AREA ON SAT. HAVE DEPICTED SCATTERED POPS REGION-WIDE FOR FRI...WITH SCATTERED POPS CONFINED MAINLY FOR NE FL AND COASTAL SE GA FOR SAT. DESPITE THE FRONTAL PASSAGE... TEMPERATURES STILL AVERAGING NEAR NORMAL. && .AVIATION...SCT CUMULUS AROUND TAF SITES WITH JUST VERY ISOLD SHOWER CELLS POPPING UP AT 1810Z. CLOSEST SCT CONVECTION TO THE TAF SITES AT THIS TIME IS JUST OF MARION COUNTY MOVING NEWD WHICH WILL MISS TAFS. HOWEVER...ISOLD TO SCT SHOWERS AND STORMS ARE EXPECTED AND COULD AFFECT TAF SITES REMAINDER OF THE AFTN AND EVENING AS AN EAST COAST SEA BREEZE IS GETTING UNDERWAY NEAR THE COAST BUT NOT CONFIDENT ENOUGH FOR INSERTING TEMPO GROUPS. BY MIDNIGHT MOST CONVECTION EXPECTED TO BE DISSIPATED BUT ISOLD CONVECTION WILL BE POSSIBLE AS DEEPER MOISTURE MOVES S TO N OVER THE AREA. && MARINE...WINDS/SEAS WILL REMAIN UNDER SCEC CRITERIA THROUGH THE MIDDLE OF NEXT WEEK...AS A HIGH PRESSURE RIDGE REMAINS FROM ACROSS THE WESTERN ATLANTIC TO THE LOCAL WATERS. WINDS WILL BE GENERALLY SOUTH OR SOUTHWEST 10 TO 15 KNOTS. SEAS 3 TO 5 FEET. RIP CURRENTS: LOW RISK THROUGH SUNDAY. && .PRELIMINARY POINT TEMPS/POPS... AMG 71 87 69 89 / 30 60 40 50 SSI 75 84 74 85 / 30 60 50 60 JAX 72 87 71 88 / 30 60 50 60 SGJ 73 85 74 86 / 30 60 50 60 GNV 71 87 71 89 / 30 60 50 50 OCF 71 88 72 90 / 40 60 50 50 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ SHASHY/PETERSON/STRUBLE
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
505 AM EDT SAT JUN 8 2013 .SYNOPSIS... 09Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THAT THE LONGWAVE UPPER LEVEL PATTERN HAS CHANGED LITTLE OVER THE PAST 24 HOURS. PATTERN IS STILL CHARACTERIZED BY BROAD RIDGING ALONG THE PACIFIC COAST AND INTER-MOUNTAIN WEST FOLLOWED DOWNSTREAM BY BROAD AND DEEP TROUGHING COVERING THE THE NATION EAST OF THE CONTINENTAL DIVIDE. OUR FORECAST AREA RESIDES WITHIN A ZONE OF DEEP SOUTHWEST FLOW BETWEEN THIS TROUGH AXIS AND UPPER LEVEL RIDGING EXTENDING ACROSS THE WESTERN ATLANTIC TO THE BAHAMAS/CENTRAL CUBA. WV IMAGERY SHOWS THE DEEPER MOISTURE IS NOW AGAIN SURGING NORTHWARD WITHIN THIS FLOW ACROSS THE CENTRAL AND NORTHERN PORTIONS OF THE FLORIDA PENINSULA. AT THE SURFACE...SUBTROPICAL RIDGE AXIS IS STILL SOUTH OF OUR AREA EARLY THIS MORNING...BUT IS PROGGED TO QUICKLY MOVE OR RE-DEVELOP NORTHWARD ACROSS THE CENTRAL PENINSULA BEFORE THE DAY IS THROUGH. REGIONAL RADARS HAVE RECENTLY SHOWN THE BEGINNING OF CONVECTIVE DEVELOPMENT OVER THE EASTERN GULF WITHIN THE DEEPER MOISTURE FIELDS AND SUPPORTED IN PART BY STRENGTHENING UPPER LEVEL DIVERGENCE WITHIN THE RRQ OF AN CONUS EAST COAST SPEED MAX. TEMPERATURES ARE WARM AND MUGGY WITH MOST LOCATIONS IN THE LOWER/MID 70S INLAND AND UPPER 70S ALONG THE COAST. QUICKLY RUNNING OUT OF TIME FOR THESE TEMPERATURES TO DROP MUCH MORE BEFORE SUNRISE. && .SHORT TERM (TODAY THROUGH MONDAY)... TODAY...A MOSTLY CLOUDY AND SHOWERY TYPE DAY LOOKS PROBABLE FOR MUCH OF THE AREA. NO WASHOUT EXPECTED...BUT THE SYNOPTIC SETUP SHOULD SUPPORT A DECENT COVERAGE OF SHOWERS/ISOLATED STORMS DURING THE COURSE OF THE DAY. AS MENTIONED IN THE SYNOPSIS...ALREADY SEEING SOME SHALLOW CONVECTION DEVELOPING OVER THE EASTERN GULF WITHIN THE DEEP SW FLOW. UPPER LEVEL DIVERGENCE FIELDS ASSOCIATED WITHIN THE RRQ OF AN IMPRESSIVE EAST COAST SPEED MAX ARE SHOWN BY THE GLOBAL GUIDANCE ENSEMBLE TO FURTHER STRENGTHEN THROUGH THE MORNING/EARLY AFTERNOON. THIS INCREASED SUPPORT FOR VERTICAL MOTION ALONG WITH THE ONSET OF DIURNAL HEATING SHOULD ONLY INCREASE THE CONVECTIVE PRODUCTION THROUGH THE MORNING HOURS. CURRENT GRIDS SHOW CHANCE POPS DURING THE FIRST PART OF THE MORNING...THEN RAMPING UP TO LIKELY CHANCES FOR MOST SPOTS BY LATE MORNING AND ESPECIALLY INTO THE AFTERNOON. MORE ABUNDANT CLOUDS AND SHOWER COVERAGE SHOULD HELP KEEP TEMPS DOWN MAINLY IN THE MID/UPPER 80S...HOWEVER THE COLUMN IS VERY WARM WITH 850MB TEMPS 17-18C...SO WILL NOT TAKE MUCH SUN TO PUSH TEMPS TOWARD 90. TONIGHT... UPPER LEVEL SPEED MAX BEGINS TO PIVOT NORTHWARD TAKING THE BEST UPPER DIVERGENCE PATTERN NORTHWARD AS WELL. THIS LOSS OF SYNOPTIC SUPPORT ALONG WITH LOSS OF DIURNAL HEATING SHOULD QUICKLY DECREASE THE SHOWER COVERAGE THIS EVENING FOR MUCH OF THE CENTRAL AND SOUTHERN FORECAST AREA. BETTER SUPPORT IS LIKELY TO LINGER OVER THE NATURE COAST...ESPECIALLY FOR CITRUS AND LEVY COUNTIES...AND THIS COMBINED WITH CONTINUED DEEP SW FLOW IS EXPECTED TO CONTINUE THE THREAT FOR SHOWERS MOVING ASHORE OFF THE GULF. WILL KEEP CHANCE POPS IN THE FORECAST FOR THESE FAR NORTHERN COUNTIES AND DROP POPS MOST OTHER LOCATIONS AFTER MIDNIGHT. LOW TEMPS WILL AGAIN FAIL TO FALL BELOW 70 AT MOST STATIONS. SUNDAY/MONDAY... SUMMER-LIKE SYNOPTIC PATTERN AND RESULTING FORECAST FOR THE SECOND HALF OF THE WEEKEND AND FIRST DAY OF THE UPCOMING WORK WEEK. SUBTROPICAL RIDGE AXIS WILL EXTEND ACROSS THE NORTHERN PORTION OF THE FL PENINSULA PROVIDING A LIGHT EAST/SE SYNOPTIC LOW LEVEL FLOW TO MUCH OF THE AREA. THE FLOW DOES NOT APPEAR STRONG ENOUGH TO SIGNIFICANTLY DISRUPT WEST-COAST SEA-BREEZE DEVELOPMENT...AND THE EVENTUAL OPPOSING FLOWS EACH AFTERNOON SHOULD RESULT IN AN ACTIVE THUNDERSTORM PATTERN FOR OUR SIDE OF THE STATE. GENERALLY LOOKING AT QUIET AND DRY CONDITIONS TO START OUT EACH DAY...FOLLOWED BY A RAMP UP IN CONVECTIVE COVERAGE DURING THE EARLY AFTERNOON WHICH WILL PEAK LATE AFTERNOON/EARLY EVENING. THE PATTERN FAVORING A WEST COAST CONVERGENCE MAX ALONG WITH A FAVORABLE THERMODYNAMIC COLUMN FOR DEEP CONVECTION SUPPORTS WIDESPREAD LIKELY (60-70%) THUNDERSTORMS CHANCES SUNDAY AFTERNOON AND EVENING. CURRENTLY HAVE HIGH END CHANCE (45-55%) THUNDER CHANCES FOR MONDAY AFTERNOON DUE TO SOME UNCERTAINLY IN THE EXTENT OF COLUMN MOISTURE. SHOULD SUFFICIENT MOISTURE BECOME MORE CERTAIN THAN AN UPGRADE TO LIKELY RAIN CHANCES MAY BECOME NECESSARY WITH FUTURE FORECAST PACKAGES. SEASONABLE TEMPS EXPECTED EACH DAY. && .LONG TERM (TUESDAY THROUGH NEXT FRIDAY)... THE PERIOD STARTS OFF WITH AN UPPER TROUGH FROM THE GREAT LAKES TO THE GULF COAST AS SURFACE HIGH PRESSURE OVER THE ATLANTIC RIDGES ACROSS NORTHERN FL TO THE GULF. DURING THE REMAINDER OF THE WEEK THE UPPER TROUGH MOVES EAST TO THE ATLANTIC COASTAL WATERS BY THU WHERE IT LINGERS THROUGH FRI...WITH A TRAILING SURFACE TROUGH REACHING THE EAST U.S. COAST. THE SURFACE RIDGE AXIS SLOWLY MOVES DOWN FL...WITH A RELAXING GRADIENT...INTO THE STRAITS SOUTH OF THE KEYS. THE UPPER TROUGH TO THE WEST ALONG WITH THE SURFACE RIDGE TO THE NORTH WILL PROVIDE ADEQUATE MOISTURE FOR MID TO HIGH END POPS FOR THE FIRST COUPLE OF DAYS. THEN AS THE TROUGH MOVES BY TO THE NORTH AND THE RIDGE DROPS SOUTH OF THE AREA SOME DRYING FILTERS IN BUT STILL ENOUGH TO KEEP POPS IN THE LOW END SCATTERED RANGE. THE LOW LEVEL FLOW VEERS FROM SOUTHEAST TO WESTERLY...WHICH WOULD FAVOR COASTAL ACTIVITY IN THE MORNINGS AND INLAND IN THE AFTERNOONS. TEMPERATURES STAY NEAR OR SLIGHTLY ABOVE NORMAL. && .MARINE... THE SUBTROPICAL RIDGE AXIS WILL REBUILD OVER THE EASTERN GULF OF MEXICO THROUGH THE WEEKEND AND REMAIN IN PLACE THROUGH THE EARLY PORTION OF NEXT WEEK. THIS POSITION WILL GENERALLY KEEP WINDS AND SEAS BELOW HEADLINE CRITERIA. THE FORMATION OF MORE DEFINED SEA-BREEZE CIRCULATION WILL RETURN FOR SUNDAY AND MONDAY NEAR THE COAST. && .AVIATION... PREVAILING VFR WITH VCNTY SHRA/TSRA FROM MID MORNING THROUGH EARLY EVENING WITH SOME MVFR IN HEAVIER TSRA DURING THE AFTERNOON. WINDS SOUTH AND SOUTHWEST DURING THE DAY...BECOMING VARIABLE TONIGHT. && .FIRE WEATHER... ABUNDANT LOW LEVEL MOISTURE WILL REMAIN IN PLACE THROUGH THE EARLY PORTION OF NEXT WEEK KEEPING RELATIVE HUMIDITY ABOVE CRITICAL LEVELS. ALTHOUGH NO DAY WILL BE A WASHOUT...RAIN CHANCES WILL REMAIN AT OR ABOVE SEASONAL NORMALS THROUGH AT LEAST MONDAY. MORE TYPICAL SEA-BREEZE DEVELOPMENT WILL ALSO RETURN FOR SUNDAY AND MONDAY CLOSE TO THE COAST. FOG POTENTIAL...SOME PATCHY LATE NIGHT AND EARLY MORNING FOG WILL BE POSSIBLE OVER THE NORTHERN NATURE COAST THE NEXT FEW DAYS...OTHERWISE NO SIGNIFICANT FOG COVERAGE IS EXPECTED. && .PRELIMINARY POINT TEMPS/POPS... TPA 87 75 90 74 / 70 20 60 30 FMY 89 74 91 74 / 60 20 70 30 GIF 90 72 92 73 / 70 20 60 30 SRQ 86 73 89 73 / 70 20 60 30 BKV 88 72 90 71 / 60 20 60 30 SPG 86 77 90 76 / 70 20 60 30 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA LONG TERM/AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
816 PM EDT SUN JUN 9 2013 .PREV DISCUSSION... /ISSUED 205 PM EDT SUN JUN 9 2013/ PREV DISCUSSION... /ISSUED 1048 AM EDT SUN JUN 9 2013/ UPDATE... MADE SLIGHT ADJUSTMENTS TO RAISE TEMPS BASED ON SOME MORNING SCATTERING OUT OF CLOUD COVERAGE IN PORTIONS OF THE NORTH. OTHERWISE...TIMING OF INCREASING POPS LOOKS TO BE ON TRACK BASED ON RECENT HI-RES MODEL RUNS AND SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT OCCURRING ACROSS CENTRAL GA AS THE GULF MOISTURE ADVECTS NORTHWARD. PWATS ALONG THE MOISTURE AXIS ARE IN THE 1.8-2.0 INCH RANGE THEREFORE PRECIPITATION SHOULD BE QUITE EFFICIENT AND PERIODS OF HEAVY RAINFALL CAN BE EXPECTED WITH STRONGER DEVELOPMENT THROUGH THE SHORT TERM. FORECAST LOOKS TO BE LARGELY ON TRACK AND PREVIOUS DISCUSSION FOLLOWS... BAKER PREV DISCUSSION... /ISSUED 752 AM EDT SUN JUN 9 2013/ PREV DISCUSSION... SHORT TERM /TODAY THROUGH MONDAY/... /ISSUED 436 AM EDT SUN JUN 9 2013/ WITH THE CWA BETWEEN RIDGING TO THE EAST AND LOW PRESSURE SYSTEM OVER THE CENTRAL CONUS...AREA IS IN SOUTHERLY FLOW AT THE SFC AND SW FLOW ALOFT. THIS HAS BROUGHT DEEP GULF MOISTURE INTO GEORGIA AND WILL MAKE FOR A RAIN FILLED SUNDAY. ALREADY HAVE AN AREA OF SHOWERS ON RADAR ACROSS CENTRAL GEORGIA. THIS WILL CONTINUE TO MOVE NORTHWARD THIS MORNING EXPANDING THE RAIN ACROSS CENTRAL GEORGIA AND BY AFTERNOON EXPECT DEVELOPMENT ALSO ACROSS NORTH GEORGIA. THIS IS SUPPORTED BY THE HRRR WHICH EXCEPT FOR BEING SLIGHTLY SLOW INITIALLY ON THE POSITIONING OF THE SHOWERS...APPEARS TO HAVE A GOOD HANDEL ON DEVELOPMENT. INSTABILITY IS STILL DECENT WITH THIS SYSTEM WHILE SHEAR IS ON THE LOWER SIDE. EXPECT SOME STORMS TO BECOME STRONG THIS AFTERNOON WITH GUSTY WINDS AND HAIL THE MAIN HAZARDS. EXTENSIVE CLOUD COVERAGE IS EXPECTED TODAY AND WILL HELP TO PLAY A ROLE IN SUPPRESSING SEVERE STORMS BUT CANNOT RULE OUT AN ISOLATED SEVERE STORM. GUIDANCE IS IN GOOD AGREEMENT WITH HIGH POPS CONTINUING OVERNIGHT...AT LEAST FOR NORTH GEORGIA. FORECAST IS FOR BETTER CHANCES IN THE FIRST HALF OF THE NIGHT. STILL LIKELY POPS IN FOR MONDAY AS THE UPPER TROUGH AXIS APPROACHES THE CWA AND WILL HELP TO ENHANCE CONVECTION. MODELS ARE SIMILAR IN SHOWING A DRY SLOT IN THE SECOND HALF OF THE PERIOD ON MONDAY SO APPEARS MONDAY MORNING AND EARLY AFTERNOON HAS THE BETTER CHANCE OF SHRA/TSRA. FOR THE MOST PART AROUND A HALF INCH OF RAIN IS EXPECTED TODAY AND ANOTHER HALF INCH TO AN INCH OVERNIGHT. WITH RAIN EXPECTED THROUGH MUCH OF THE SHORT TERM...WILL HAVE TO CONTINUE TO MONITOR RAINFALL AMOUNTS CLOSELY FOR ANY ISOLATED FLOODING. 11 LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... LONG TERM PERIOD BEGINS WITH A STRONG SHORTWAVE MOVING THROUGH THE TENNESSEE VALLEY AND INTO NORTH GEORGIA PROVIDING FOR AN ENHANCED THUNDERSTORM RISK INTO THE OVERNIGHT. IN FACT...WITH TIMING OF SHORTWAVES...MUCH OF THE EXTENDED PERIOD WILL FEATURE POPS HIGHER DURING THE OVERNIGHT HOURS THAN THE DAYTIME...CERTAINLY AN ODDITY THIS TIME OF YEAR. FOR FIRST SHORTWAVE INTO TUESDAY MORNING WILL CARRY LIKELY POPS FOR THE NORTHERN TIER TRANSITIONING TO JUST MID RANGE SCATTERED FOR CENTRAL GEORGIA ON TUESDAY AS SHORTWAVE SHEARS OUT AND LIFTS NORTHEAST OF THE LOCAL AREA. ALTHOUGH DRIER AIR WILL WORK IN LATE TUESDAY...AREA WILL BE ON THE EASTERN SIDE OF UPPER RIDGE WITH A SERIES OF SHORTWAVES TO MOVE THROUGH. GFS SHOWS POTENT DISTURBANCE TUESDAY NIGHT...AGAIN WITH LIMITED MOISTURE...BUT ENOUGH TO WARRANT SCATTERED POPS INTO THE OVERNIGHT HOURS. MODELS REMAIN CONSISTENT IN DEPICTING STRONGEST SHORTWAVE ON THU WHICH LOOKS TO HAVE A SURFACE REFLECTION WITH AND ALLOWS A WEAK FRONT TO PUSH THROUGH THE REGION. SURFACE CONVERGENCE ALONG THIS FEATURE ALONG WITH AFOREMENTIONED UPPER SUPPORT AND HIGHER INSTABILITY THAN PREVIOUS DAYS WILL RESULT IN HIGH THUNDERSTORM CHANCES THROUGH THU EVENING. AS FRONT CLEARS...EVEN DRIER AIR WORKS INTO THE AREA LIMITING RAIN CHANCES FURTHER. WE WILL STILL SEE STRONG SHORTWAVES MOVE THROUGH ON EAST SIDE OF UPPER RIDGE BUT POPS WILL BE LIMITED TO LOW END CHANCE AT BEST FOR THE REMAINDER OF THE PERIOD. DEESE && .AVIATION... 00Z UPDATE... MAINLY SOUTHWESTERLY FLOW OVER THE AREA WITH SHOWERS AND ISOLATED THUNDERSTORMS MOVING ACROSS THE STATE. THIS PRECIPITATION IS EXPECTED TO CONTINUE THROUGH 14-16Z MON. CEILINGS ARE UP AND DOWN BUT MAINLY STAYING IN THE VFR TO MVFR RANGE. CEILINGS WILL LOWER INTO THE IFR RANGE OVER NIGHT THEN LIFT BACK TO VFR BY 16-18Z MON. WINDS WILL STAY MAINLY OUT OF THE SW BUT THEY MAY TURN BRIEFLY TO THE SE BETWEEN 02-06Z. WIND SPEEDS WILL STAY IN THE 5-10KT RANGE EXCEPT IN AND AROUND SHRA/TSRA DEVELOPMENT. //ATL CONFIDENCE...00Z UPDATE... CONFIDENCE MEDIUM ON ALL ELEMENTS. 01 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 67 82 68 89 / 80 60 40 40 ATLANTA 67 82 69 86 / 80 60 30 30 BLAIRSVILLE 65 78 64 82 / 80 60 60 20 CARTERSVILLE 68 83 68 88 / 80 60 50 20 COLUMBUS 70 86 71 91 / 70 60 30 40 GAINESVILLE 67 79 67 86 / 80 60 50 30 MACON 70 85 69 90 / 70 60 40 40 ROME 69 84 67 88 / 80 60 60 20 PEACHTREE CITY 68 82 67 88 / 80 60 30 30 VIDALIA 72 87 72 90 / 60 60 50 40 && .FFC WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH MONDAY MORNING FOR THE FOLLOWING ZONES: BANKS...BARROW...BARTOW...CATOOSA...CHATTOOGA... CHEROKEE...CLARKE...COBB...DADE...DAWSON...DEKALB...FANNIN... FLOYD...FORSYTH...GILMER...GORDON...GWINNETT...HALL...JACKSON... LUMPKIN...MADISON...MURRAY...NORTH FULTON...OCONEE... OGLETHORPE...PICKENS...TOWNS...UNION...WALKER...WALTON...WHITE... WHITFIELD...WILKES. && $$ SHORT TERM...01 LONG TERM....DEESE AVIATION...01
AREA FORECAST DISCUSSION
NWS POCATELLO ID
904 PM MDT SUN JUN 9 2013 .UPDATE...WV IMAGERY SHOWS WELL WRAPPED UPPER LOW ALONG CALIFORNIA COAST BEGINNING TO EJECT NORTHEAST TOWARD THE GREAT BASIN. MOISTURE WRAPPING AROUND THE LOW ALREADY PRODUCING MODERATE CONVECTION THROUGH PORTIONS OF THE GREAT BASIN...BUT HAVING A VERY DIFFICULT TIME MAKING IT FURTHER NORTH THAN INTERSTATE 80. UPPER LEVEL BLOW OFF FROM THE CONVECTION IN NEVADA BEGINNING TO PUSH INTO SOUTHERN IDAHO ALONG THE STATE LINE. MODELS STILL HAVING ISSUES NAILING DOWN TIMING OF CONVECTIVE ONSET OVER EASTERN IDAHO. EARLY LOOK AT 00Z NAM HOLDS OFF PRECIPITATION UNTIL LATE MONDAY MORNING. HOWEVER...LATEST HRRR AND TO SOME EXTENT THE 18Z LOCAL WRF BOTH INDICATE POTENTIAL FOR TRACE EVENT QPF OVER PORTIONS OF EASTERN IDAHO AFTER MIDNIGHT. CONFIDENCE STILL FAIRLY LOW FOR OVERNIGHT CONVECTION AND WILL LEAVE CURRENT DRY GRIDS IN PLACE. ONLY OTHER CONCERN WILL BE WINDS FOR DURING THE DAY MONDAY. LATEST NAM DROPS CENTER OF STRONG DEVELOPING SURFACE LOW OVER THE EASTERN MAGIC VALLEY LATE IN THE DAY WITH 700MB 40+KT JET SURGING NORTH EAST OF THE LOW. POTENTIAL FOR STRONG WINDS IN THE LOWER AND UPPER SNAKE PLAIN LATE MONDAY IF THIS SOLUTION HOLDS TRUE WITH HEADLINE FOR STRONG WINDS POSSIBLE. WOULD LIKE TO SEE WHAT GFS HAS TO SAY FOR MONDAY. AT THIS TIME...NO UPDATES FOR EASTERN IDAHO FOR TONIGHT. DMH && .PREV DISCUSSION... /ISSUED 226 PM MDT SUN JUN 9 2013/ SHORT TERM...A DRY WESTERLY FLOW PATTERN OVER SOUTHEAST IDAHO TONIGHT. FOCUS IS ON THE LOW PRESSURE CIRCULATION JUST OFF THE CALIFORNIA COAST. THE 12Z MODEL RUNS MADE SOME SUBTLE CHANGES OVER PREVIOUS RUNS...UPPER LOW CIRCULATION STILL TRACKS THROUGH POINT CONCEPTION TO ABOUT DESERT ROCK NEVADA BY MONDAY AFTERNOON...THEN TO NEAR WENDOVER UTAH BY TUESDAY MORNING. THERE ALSO IS A MINOR DISTURBANCE RIPPLING ALONG THE CANADIAN BORDER WHICH FLATTENS THE FLOW AND NUDGES THE PATTERN SLIGHT SOUTH BY EARLY MONDAY. THIS SEEMS TO RESULT IN LIGHTER AND MORE WESTERLY WINDS TONIGHT IN THE SOUTH CENTRAL HIGHLANDS...LESS DOWN SLOPE AND NOT SO WARM TEMPERATURES FOR MONDAY MORNING. THE GFS IS ALSO MUCH DRIER ACROSS THE CENTRAL MOUNTAINS MONDAY AFTERNOON. TRIED TO STAY WITH THE NAM FOR CONVECTION MONDAY. STRENGTH OF THE WINDS OVER AMERICAN FALLS RESERVOIR MONDAY AFTERNOON IS MARGINAL FOR A LAKE WIND ADVISORY AND DECIDED TO LET THE MID SHIFT TAKE ONE MORE LOOK BEFORE ISSUING. SOUTH WINDS DO PICK UP MONDAY...BUT ARE SHIFTED A LITTLE FURTHER EAST TOWARDS THE CARIBOU HIGHLANDS IN BOTH THE GFS AND NAM MODELS. LOOKS LIKE THERE IS ENOUGH WARM TEMPERATURE ADVECTION TO SUPPORT RECORD HIGH TEMPERATURES AT POCATELLO...IDAHO FALLS MAY BE PLUS OR MINUS ONE DEGREE OFF THE RECORD. AIR MASS REMAINS UNSTABLE MONDAY NIGHT...A 700MB TROUGH CROSSING FORECAST AREA COULD SET OFF THUNDERSTORMS EARLY TUESDAY MORNING. STARTING TUESDAY MORNING...THE NAM SPEEDS UP PROGRESSION OF THE LOW NEAR WENDOVER AND DRIES THIS AREA OUT QUICKER...GFS IS SLOWER. RETAINED A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS IN THE FORECAST FOR TUESDAY NIGHT AND WILL LOOK TO SEE IF MODEL TIMING IS CONSISTENT NEXT RUN. RS LONG TERM...WEDNESDAY MORNING THROUGH SUNDAY. WEDNESDAY THE GFS AND ECMWF MODELS CONTINUE TO BRING MOISTURE AHEAD OF A SYSTEM THAT THEY SHOW SKIRTING OUR NORTHERN AREAS ON THURSDAY AFTERNOON INTO FRIDAY MORNING. THE ECMWF CONTINUES TO MOVE THIS SYSTEM SLIGHTLY FARTHER SOUTH OVER OUR AREA SHOWING MORE PRECIPITATION. LOOK FOR MOST OF THE PRECIPITATION TO BE IN THE MOUNTAINS OVER THE CENTRAL MOUNTAINS AND UPPER SNAKE HIGHLANDS. LOOK FOR NEAR NORMAL TEMPERATURES EARLY IN THE PERIOD BECOMING SLIGHTLY BELOW NORMAL THURSDAY INTO FRIDAY. HIGH PRESSURE WILL BUILD IN SATURDAY INTO SUNDAY BRINGING DRIER CONDITIONS AND SLIGHTLY WARMER THAN NORMAL TEMPERATURES SATURDAY AND SUNDAY IN PARTICULAR. WYATT AVIATION...EXPECT VFR CONDITIONS THE 24 HOURS. CURRENTLY THERE IS HIGH PRESSURE RIDGING ALOFT WITH WESTERLY FLOW. EXPECT BREEZY WINDS FOR ALL TAF SITS THIS AFTERNOON INTO EARLY EVENING. EXPECT A MODERATE TO STRONG SOUTH SOUTHWEST FLOW BY TOMORROW AFTERNOON BRING STRONGER WINDS FOR ALL TAF SITES. EXPECT A SLIGHT CHANCE OF AFTERNOON THUNDERSTORMS TOMORROW PARTICULARLY FOR KSUN. WYATT && .PIH WATCHES/WARNINGS/ADVISORIES... NONE. && $$
TO ACCOUNT FOR LATEST TRENDS. PREVIOUS FORECAST DISCUSSION
FOLLOWS...
PRECIPITATION LOOKS LIKE A GOOD BET ACROSS CENTRAL INDIANA TONIGHT. THE FIRST SHOT LOOKS TO ARRIVE FROM THE SOUTH AS THE PRECIP OVER KENTUCKY ADVECTS INTO CENTRAL INDIANA. THE GFS 305K ISENTROPIC SURFACE SHOWS GOOD LIFT ASSOCIATED WITH THIS FEATURE ADVECTING NORTHEAST ACROSS THE EASTERN PARTS OF OUR FORECAST AREA LATE THIS AFTERNOON AND EARLY THIS EVENING. THE SECOND SHOT AT PRECIPITATION COMES AFTER 00Z AS THE PRECIP ASSOCIATED WITH THE TROUGH OF LOW PRESSURE ARRIVES. GOOD LOWER LEVEL Q VECTOR CONVERGENCE PUSHES THROUGH THE AREA WITH THE TROUGH OF LOW PRESSURE AS THE HRRR SUGGESTS AN AREA OF SHRA WITH TSRA PUSHING THROUGH THE STATE THIS EVENING. FURTHERMORE...FORECAST SOUNDINGS INDICATE GOOD SATURATION...PARTICULARLY DURING BY 06Z TIME FRAME. THUS WILL TREND POPS HIGHER THAN MAVMOS...PARTICULARLY EARLY ON IN THE EAST AS THE TSRA AND SHRA ARE EXPECTED TO MOVE IN AND ACROSS THE AREA AND THEN AGAIN ACROSS THE WEST AND CENTRAL AREA DURING THE MIDDLE TO LATER PARTS OF THE FORECAST PERIOD. GIVEN THE CLOUDS AND RAIN WILL TREND LOWS AT OR ABOVE MAVMOS. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... ISSUED AT 103 PM EDT SUN JUN 9 2013 MAIN FORECAST CHALLENGE FOR THIS PERIOD WILL BE POPS N MONDAY. GFS AND NAM DEPICT THE LOW PRESSURE SYSTEM OVER IOWA PUSHING THROUGH AND EXITING CENTRAL INDIANA ON MONDAY AFTERNOON. BROAD CYCLONIC LOWER LEVEL FLOW WILL BE IN PLACE. FORECAST SOUNDINGS SHOWS STEEP LAPSE RATES BY 18Z MONDAY WITH GOOD MOISTURE STILL AVAILABLE. CAPE REMAINS IN EXCESS OF 1000 J/KG AND CONVECTIVE TEMPS ARE ONLY IN THE LOWER 70S. THUS GIVEN THE FLOW...THE FORCING AND DAYTIME HEATING SOME SCT SHRA AND ISOLATED TSRA WILL BE POSSIBLE. WILL STICK CLOSE TO THE TO THE MAVMOS POPS HERE GIVEN THE HIT OR MISS CHANCES OF CONVECTIVE PRECIP IN THIS SET UP. WITH LITTLE CHANGE IN THE AIR MASS WILL USE A BLEND ON HIGHS AS GOOD CLOUD COVER COULD BE PRESENT WITH THE PASSING LOW. THE LOW PRESSURE SYSTEM DEPARTS ON MONDAY AND AS GOOD RIDGING BUILDS ALOFT ON MONDAY NIGHT THROUGH TUESDAY. TIME HEIGHTS AND FORECAST SOUNDINGS DRY OUT THE COLUMN CONSIDERABLE AS THE CONVECTIVE TEMPS BECOME UNREACHABLE. AGAIN THERE IS VERY LITTLE CHANGE IN THE AIR MASS FOR THIS SYSTEM AND AS THE RIDGE QUICKLY MOVES EAST OF INDIANA BY LATE TUESDAY...STRONG WARM AIR ADVECTION ONCE AGAIN TAKES SHAPE ACROSS CENTRAL INDIANA. THE GFS FORECAST SOUNDINGS HINT EVEN WITH THE WARM AND HUMID AIR MASS IN PLACE 700MB TEMPS WILL BE NEAR 12C...WHICH IS USUALLY A PRETTY DARN GOOD CAP. THUS WILL KEEP A DRY FORECAST FROM MONDAY NIGHT THROUGH WEDNESDAY...WITH SLOWLY MODERATING TEMPERATURES WARMER EACH DAY. WILL TREND TOWARD THE WARMER SIDE OF GUIDANCE DURING THE MONDAY NIGHT THROUGH WEDNESDAY TIME PERIOD. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... ISSUED AT 250 PM EDT SUN JUN 9 2013 MAIN FOCUS OF THE EXTENDED WILL BE STORM CHANCES WEDNESDAY NIGHT... EARLY THURSDAY AND AGAIN OVER THE WEEKEND. MODELS REMAIN IN GOOD AGREEMENT IN MAINTAINING A NORTHWEST FLOW ALOFT ACROSS THE NORTHERN U.S. FROM THE PLAINS EASTWARD. A STRONG UPPER RIDGE WILL BE OVER TEXAS AND OKLAHOMA WHILE AN UPPER UPPER TROUGH MOVES FROM THE GREAT LAKES INTO NEW ENGLAND AROUND THURSDAY FOLLOWED BY A WEAKER SYSTEM LATE SATURDAY NIGHT AND SUNDAY. MODELS HAVE TRENDED A LITTLE WETTER AND FARTHER SOUTH WITH A POSSIBLE MCS MOVING ACROSS OUR REGION WEDNESDAY NIGHT. SCATTERED THUNDERSTORMS MAY LINGER INTO THURSDAY. HOWEVER WITH THE MODELS BEING VERY QUICK TO DRY US OUT...WILL DROP MENTION OF THUNDERSTORMS FOR THURSDAY AFTERNOON. THURSDAY NIGHT THROUGH EARLY SATURDAY WILL BE DRY AS A WEAK RIDGE OF HIGH PRESSURE MOVES EAST ACROSS OUR REGION. MODELS ARE A LITTLE MORE PROGRESSIVE WITH THE WEEKEND. BUT THEY MAY BE A BIT TOO FAST. FOR NOW LEAN TOWARDS THE SLOWER HPC SOLUTION. WENT WITH A MOS BLEND MOST PERIODS...EXCEPT A TAD WARMER FOR HIGHS FRIDAY AND SATURDAY AS THERE WILL BE LOTS OF SUN AND INCREASING WARM ADVECTION. && .AVIATION /DISCUSSION FOR 100300Z TAF UPDATE/... ISSUED AT 1023 PM EDT SUN JUN 9 2013 SHOWERS AND THUNDERSTORMS ARE JUST WEST OF KIND AT THE MOMENT...AND LATEST RADAR TRENDS SHOW THAT SHOWERS AND EMBEDDED THUNDERSTORMS SHOULD MOVE OVER KIND FOR THE NEXT FEW HOURS. WILL CONTINUE WITH TEMPO MENTION. COULD BE IFR IN HEAVIER RAIN. PREVIOUS DISCUSSION FOLLOWS... MVFR IN SHOWERS AND STORMS AT TIMES THROUGH 05Z OR SO...THEN MVFR CONDITIONS UNTIL LATE MORNING MONDAY. A COUPLE OF LINES OF SHOWERS AND THUNDERSTORMS WILL IMPACT THE TAF SITES IN THE FIRST QUARTER OR SO OF THE TAF PERIOD. SCATTERED CONVECTION WILL BE AHEAD OF THE LINES. TRIED TO TIME WITH TEMPOS THE BEST WINDOW FOR CONVECTION. MVFR CONDITIONS EXPECTED IN CONVECTION...WITH POTENTIAL FOR BRIEF PERIODS OF IFR. AFTER THE LINES MOVE THROUGH SOME ADDITIONAL SCATTERED SHOWERS WILL PERSIST INTO MID MORNING MONDAY AS AN UPPER LOW MOVES IN. PREDOMINANT MVFR CEILINGS AND PERHAPS VISIBILITIES WILL MOVE IN OVERNIGHT AND PERSIST THROUGH MONDAY MORNING AS THE UPPER LOW MOVES IN. CEILINGS SHOULD LIFT TO VFR BY 17Z OR SO. OUTSIDE OF POTENTIAL GUSTY WINDS IN THUNDERSTORMS...WINDS WILL REMAIN NEAR OR BELOW 10KT FOR THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...PUMA NEAR TERM...SMF/PUMA SHORT TERM...PUMA LONG TERM....JEH AVIATION...50 VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
344 PM CDT SAT JUN 8 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 343 PM CDT SAT JUN 8 2013 AN UPPER LEVEL TROUGH ACROSS EASTERN WY AND WESTERN NE WILL DIG SOUTHEAST ACROSS NE AND KS TONIGHT. A SURFACE COLD FRONT EXTENDED FROM CENTRAL NE...SOUTHWEST ACROSS WESTERN KS. ONLY ELEVATED SHOWERS WERE FORMING EARLY THIS AFTERNOON ACROSS NORTH CENTRAL AND CENTRAL KS AHEAD OF SOMEWHAT DEEPER MOISTURE RETURN ACROSS WESTERN OK INTO SOUTH CENTRAL KS. THE RESULTING MID LEVEL CLOUD COVER AND ELEVATED SHOWERS HAVE KEPT THE AIRMASS MORE STABLE AHEAD OF THE COLD FRONT. THE MESOSCALE MODELS CONTINUE TO FORECAST A LINE OF SHOWERS AND THUNDERSTORMS DEVELOPING AROUND 22Z AHEAD OF THE SURFACE COLD FRONT AND IN THE AREA OF STRONGER ASCENT AHEAD OF THE DIGGING H5 TROUGH ACROSS NORTH CENTRAL AND CENTRAL KS. THIS LINE OF STORMS WILL MOVE EAST ACROSS THE CWA. THE ONLY QUESTION IS TO THE DEGREE THE ATMOSPHERE WILL DESTABILIZE AHEAD OF SFC BASED STORMS DEVELOPING AHEAD OF THE SURFACE COLD FRONT LATER THIS AFTERNOON. AT THIS TIME IT LOOKS AS IF THE THREAT FOR ANY WIDESPREAD SEVERE WEATHER IS DIMINISHING ACROSS THE CWA LATE THIS AFTERNOON AND EVENING. THE SPC EMC RAP MODEL SHOWS THE GREATEST INSTABILITY DEVELOPING AHEAD OF THE COLD FRONT ACROSS SOUTHWEST KS...SOUTHWARD INTO THE TX PNHDL. IF THERE IS SOME CLEARING BEHIND THE ELEVATED SHOWERS...THEN PERHAPS SBCAPES MAY INCREASE TO 1500 J/KG LATE THIS AFTERNOON AND EARLY THIS EVENING AND THERE COULD BE AN ISOLATED SEVERE THUNDERSTORMS THREAT ALONG THE DEVELOPING SQUALL LINE...ESPECIALLY ACROSS THE WESTERN COUNTIES OF THE CWA. ATTM...THE PRIMARY HAZARDS MAY BE GUSTY WINDS OF 50 MPH TO 60 MPH AND QUARTER SIZE HAIL. THERE MAY BE SOME BRIEF HEAVY RAINFALL WHICH COULD CAUSE SOME LOCALIZED FLOODING. THE SHOWERS AND THUNDERSTORMS SHOULD PUSH EAST OF THE CWA AS THE H5 TROUGH SHIFTS EAST INTO IA AND EXTENDS SOUTH THROUGH MO EARLY SUNDAY MORNING. SUNDAY...WESTERLY WINDS BEHIND THE FRONT WILL ADVECT DRIER AIR EAST. SKIES WILL CLEAR THROUGH THE MORNING HOURS. THE UPPER TROUGH ACROSS IA WILL DEEPEN INTO A CLOSED UPPER LOW. THE NORTHEAST COUNTIES MAY DESTABILIZE ENOUGH UNDER THE SOUTHWESTERN EDGE OF THE COLD CORE UPPER LOW LOW FOR ISOLATED SHOWERS AND THUNDERSTORMS TO DEVELOP DURING THE MID AND LATE AFTERNOON HOURS. THESE SHOWERS WILL DISSIPATE AFTER SUNSET. HIGHS WILL REACH THE UPPER 70S TO LOWER 80S. GARGAN .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 343 PM CDT SAT JUN 8 2013 BY SUNDAY NIGHT...THE UPPER LEVEL TROUGH ASSOCIATED WITH THIS WEEKEND`S PRECIPITATION WILL BE PUSHING EAST OF THE AREA WITH AN UPPER LEVEL RIDGE BUILDING IN BEHIND IT. MODELS SHOW THIS RIDGE BUILDING ACROSS THE SOUTHERN AND CENTRAL PLAINS BY TUESDAY AND DEVELOPING INTO A BROAD RIDGE THAT DOMINATES MUCH OF THE SOUTHERN CONUS THROUGH THE END OF THE WEEK AND EVEN INTO THE WEEKEND. WITH THIS BROAD RIDGE FIRMLY IN PLACE...MORE OF A BLOCKING PATTERN WILL SET UP AS MODELS SHOW SEVERAL UPPER LEVEL TROUGHS OR SHORTWAVE TROUGHS SKIMMING EASTWARD ACROSS CANADA AND THE NORTHERN U.S. HAVE KEPT THE FORECAST DRY THROUGH THE WEEK INTO THE WEEKEND...HOWEVER THIS MAY BE DEPENDENT UPON JUST HOW FAR NORTH THIS UPPER RIDGE STRETCHES INTO THE NORTHERN AND CENTRAL PLAINS. WITH THE SEVERAL SHORTWAVES EXPECTED TO DEVELOP ALONG THE NORTHERN EDGE OF THE RIDGE...MODELS CURRENTLY SHOW ANY ASSOCIATED PRECIPITATION REMAINING NORTH OF THE CWA...BUT IF THE RIDGE WEAKENS SOME THERE MAY BE THE POTENTIAL FOR SOME SCATTERED PRECIPITATION CHANCES TO DIP FURTHER SOUTH ACROSS EXTREME NORTHERN AND NORTHEASTERN KANSAS. MAIN FOCUS FOR THE EXTENDED PERIOD THOUGH IS WITH THE RISING TEMPERATURES. MODEL SOUNDINGS SHOW DECENT MIXING FROM 800-850MB DOWN TO THE SURFACE THROUGH MUCH OF THE WEEK...WITH 850MB TEMPERATURES UPWARDS OF 21C-28C. ONE OF THE WARMEST DAYS LOOKS TO BE TUESDAY AS STRONG SOUTHERLY FLOW AIDS IN DECENT WARM AIR ADVECTION INTO THE REGION WITH 25C-28C 850MB TEMPERATURES EXPECTED TO MIX DOWN. HIGH TEMPERATURES THROUGH THE WEEK INTO THE WEEKEND LOOK TO REMAIN IN THE UPPER 80S TO LOWER AND MIDDLE 90S...WITH OVERNIGHT LOW TEMPERATURES ALSO REMAINING QUITE MILD IN THE UPPER 60S TO LOWER 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1253 PM CDT SAT JUN 8 2013 EXPECT VFR CONDITIONS THROUGH 00Z SUN AT THE TAF SITES. SOUTH WINDS WILL CONTINUE AT 14 TO 18 KTS WITH GUSTS OF 24 TO 29 KTS THROUGH THE AFTERNOON HOURS. A LINE OF THUNDERSTORMS WILL MOVE EAST ACROSS THE TAF SITES THIS EVENING BRINGING GUSTY WINDS AND BRIEF HEAVY RAINFALL. MAY SEE SOME MVFR CEILINGS AND VISIBILITIES WITHIN THE LINE OF THUNDERSTORMS. ONCE THE THUNDERSTORMS PASS TO THE EAST LATE THIS EVENING...THEN CONDITIONS SHOULD BECOME VFR AGAIN...WITH WESTERLY SURFACE WINDS. GARGAN && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GARGAN LONG TERM...HENNECKE AVIATION...GARGAN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
222 PM CDT SAT JUN 8 2013 ...UPDATE TO LONG TERM/FIRE WX SECTIONS... .SYNOPSIS... ISSUED AT 119 PM CDT SAT JUN 8 2013 A NORTHWEST FLOW JET STREAKED WAS IMPINGING ON WESTERN KANSAS MID-AFTERNOON. PRONOUNCED MID-TROPOSPHERIC DRYING WAS EVIDENT ON WATER VAPOR LOOP IN THE LEFT-FRONT QUADRANT OF THE JET STREAK FROM NEAR CHEYENNE, WY NORTHWARD INTO CENTRAL/EASTERN MONTANA. THERE WAS AN AXIS OF ENHANCED MID-LEVEL MOISTURE JUST AHEAD OF THE DRY INTRUSION. THIS PROMOTED DEVELOPMENT OF ACCAS AND ATTENDANT SPRINKLES/LIGHT RAIN SHOWERS FROM NORTHWESTERN/NORTH-CENTRAL KANSAS INTO CENTRAL AND WESTERN NEBRASKA. THE BOUNDARY LAYER WAS ONLY MARGINALLY MOIST WITH EARLY AFTERNOON DEWPOINT TEMPERATURES MAINLY IN THE MID-50S DEGF. THE FRONT AT 18Z EXTENDED FROM NEAR JOHNSON TO SCOTT CITY TO HILL CITY...WITH A CONTINUED PUSH SOUTH AND EAST. AS OF 18Z...THE ENVIRONMENTAL SETTING ALONG AND AHEAD OF THE FRONT WAS MARGINALLY UNSTABLE WITH SBCAPE AROUND 1500 J/KG...MAINLY ACROSS FAR SOUTHWESTERN KANSAS. PER SPC MESOSCALE ANALYSIS PAGE AT 18Z, 0-6KM AGL BULK SHEAR VALUES OF AROUND 35 KNOTS WITH NEARLY 90-DEGREE VEERING IN THE 850-500MB LAYER SUPPORT ORGANIZED CONVECTIVE STRUCTURES, INCLUDING SUPERCELLS. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 119 PM CDT SAT JUN 8 2013 CONVECTIVE MODE, DURATION, SEVERITY ARE THE MAIN CHALLENGE IN THE "TONIGHT" PERIOD OF THE FORECAST. JUST ABOUT ALL SHORT-TERM HIGH RESOLUTION MODELS SHOW CONVECTIVE DEVELOPMENT AT OR SHORTLY AFTER 20Z ALONG THE FRONT. THE HRRR DOES SUGGEST INDIVIDUAL COHERENT CELLS (PERHAPS SUPERCELLS) AS THE INITIAL MODE. THE PREVIOUS FORECAST CONCERN FOR HAIL UP TO GOLFBALL SIZE IN THE STRONGEST STORM STILL LOOKS JUSTIFIED. ONCE AN ESTABLISHED COLD POOL IS GENERATED...THE GROWTH UPSCALE WILL LEAD TO A TRANSITION IN SEVERE THREAT FROM ONE OF LARGE HAIL TO ONE OF DAMAGING STRAIGHT LINE WINDS. WHEN AND WHERE EXACTLY THIS WILL TRANSITION IS STILL UNCERTAIN...BUT BY 00Z THE GENERAL THINKING IS THAT CONVECTIVE MODE SHOULD BE QUASI-LINEAR...ESPECIALLY IN THE CENTRAL AND SOUTH-CENTRAL KANSAS PORTION OF THE DDC FORECAST AREA (ALONG AND EAST OF HIGHWAY 183). FARTHER SOUTH AND WEST...SUPERCELL STRUCTURES MAY LAST A BIT LONGER WITH SLIGHTLY A BIT MORE CAPPING TO KEEP CONVECTION FROM GROWING UPSCALE TOO QUICKLY. NO CHANGE WAS REQUIRED IN THE POP/WX GRIDS WITH 60-70 POPS STILL QUITE REASONABLE. STRONG/SEVERE CONVECTION SHOULD CLEAR THE ENTIRE DDC FORECAST AREA (EAST AND SOUTH OF BARBER, COMANCHE, PRATT COUNTIES) DURING THE 01-03Z TIME FRAME AS THE FRONT CONTINUES ITS PUSH SOUTH AND EAST. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 222 PM CDT SAT JUN 8 2013 SUMMER IS HERE TO STAY. SUNDAY NIGHT/MONDAY: DURING LATE NIGHT SUNDAY INTO MONDAY MORNING, WINDS WILL EVENTUALLY VEER SOUTHERLY. THIS SHOULD KEEP MINS IN THE UPPER 60S ALONG THE OKLAHOMA BORDER TO LOWER 60S ALONG INTERSTATE 70. 500 HPA RIDGING AND ASSOCIATED SUBSIDENCE WILL KEEP THE FORECAST PRECIPITATION FREE FOR THE BEGINNING OF THE WORK WEEK. MAXIMUM TEMPERATURES MONDAY WILL BE VERY WARM TO HOT WITH HIGHS IN THE UPPER 90S TO LOWER 100S. THE WARMEST TEMPS ARE EXPECTED ALONG THE COLORADO BORDER WHERE 850 HPA TEMPERATURES WILL BE NEAR 34 DEG C. HAVE USED ECMWF FOR TEMP GUIDANCE AND NUDGED TEMPS DOWN AS THIS MODEL TYPICALLY OVERDOES A SUPER ADIABATIC LAPSE RATE NEAR THE SURFACE. TUESDAY: A LEE INDUCED LOW/TROF WILL STRENGTHEN TUESDAY. THIS WILL CREATE STRONGER DOWNSLOPE WINDS AND THE 850 HPA WARM PLUME WILL ADVECT FARTHER EAST. VALUES IN THE 32-36 DEG C RANGE ARE EXPECTED ACROSS THE REGION. THIS SUPPORTS MIX DOWN TEMPERATURES (OBVIOUSLY MUCH HIGHER THAN 850 HPA) IN THE LOW 100S. AGAIN, USED THE ECMWF AS A BASIS AND THE NUDGED DOWN TO REDUCE THE IMPACTS FROM THE MODEL GENERATED SUPER ADIABATIC LAPSE RATE. NO PRECIPITATION IS EXPECTED AS A STRONG 591 DM RIDGE CONTINUES ALONG WITH ASSOCIATED SUBSIDENCE THROUGH THE ATMOSPHERIC COLUMN. LASTLY, CRITICAL FIRE WEATHER CONDITIONS HAVE BEEN ADDRESSED IN THE FIRE WX SECTION BELOW. WEDNESDAY AND BEYOND: MORE OF THE SAME IS EXPECTED FOR THE REST OF THE FORECAST PERIOD. A WEAK FRONT MAKE TRAVERSE THE REGION WEDNESDAY, HOWEVER COMPRESSIONAL WARMING AHEAD OF THE FRONT WILL LEAD TO HOT TEMPERATURES SOUTH OF THE FRONT. THERE WILL NOT BE MUCH IN THE WAY OF COLD AIR ADVECTION ASSOCIATED WITH THE FRONT, SO NORTHERN ZONES MAY "COOL OFF" TO THE 90S. THURSDAYS ONWARDS, THE 850 HPA WARM PLUME WILL REDEVELOP AND ADVECT EASTWARDS ON FRIDAY. THIS SUPPORTS HOT TEMPERATURES IN THE LOW 100S. MINIMUMS WILL BE IN THE 70S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1254 PM CDT SAT JUN 8 2013 A COLD FRONT WILL MOVE ACROSS THE SOUTHWEST AND WEST-CENTRAL KANSAS REGION THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED IN VICINITY OF HYS, GCK, AND DDC TERMINALS LATE THIS AFTERNOON THROUGH EARLY EVENING (ROUGHLY 22Z THROUGH 01Z TIME FRAME). BEHIND THE FRONT...NORTH TO NORTHEAST WINDS OF 15 TO 20 KNOTS IS EXPECTED INITIALLY...WITH A DECREASE IN WIND SPEED AFTER 06Z SUNDAY. && .FIRE WEATHER... ISSUED AT 222 PM CDT SAT JUN 8 2013 CRITICAL FIRE WEATHER CONDITIONS STILL LOOK POSSIBLE TUESDAY AFTERNOON. THIS IS A RESULT OF HOT TEMPERATURES, LOW DEWPOINTS, AND BREEZY/WINDY SOUTHWESTERLY DOWNSLOPE WINDS. RH`S COULD STILL BE AOB 15 PERCENT WEDNESDAY ONWARD, BUT WINDS ARE MORE UNCERTAIN AT THIS TIME. && .PRELIMINARY POINT TEMPS/POPS... DDC 60 91 65 100 / 40 0 0 0 GCK 58 91 65 101 / 30 0 0 0 EHA 59 93 69 101 / 30 0 0 0 LBL 61 93 67 102 / 40 0 0 0 HYS 58 87 61 96 / 20 10 0 0 P28 63 89 67 97 / 70 10 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...UMSCHEID SHORT TERM...UMSCHEID LONG TERM...SUGDEN AVIATION...UMSCHEID FIRE WEATHER...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
120 PM CDT SAT JUN 8 2013 ...UPDATED SYNOPSIS AND SHORT TERM SECTIONS... .SYNOPSIS... ISSUED AT 119 PM CDT SAT JUN 8 2013 A NORTHWEST FLOW JET STREAKED WAS IMPINGING ON WESTERN KANSAS MID-AFTERNOON. PRONOUNCED MID-TROPOSPHERIC DRYING WAS EVIDENT ON WATER VAPOR LOOP IN THE LEFT-FRONT QUADRANT OF THE JET STREAK FROM NEAR CHEYENNE, WY NORTHWARD INTO CENTRAL/EASTERN MONTANA. THERE WAS AN AXIS OF ENHANCED MID-LEVEL MOISTURE JUST AHEAD OF THE DRY INTRUSION. THIS PROMOTED DEVELOPMENT OF ACCAS AND ATTENDANT SPRINKLES/LIGHT RAIN SHOWERS FROM NORTHWESTERN/NORTH-CENTRAL KANSAS INTO CENTRAL AND WESTERN NEBRASKA. THE BOUNDARY LAYER WAS ONLY MARGINALLY MOIST WITH EARLY AFTERNOON DEWPOINT TEMPERATURES MAINLY IN THE MID-50S DEGF. THE FRONT AT 18Z EXTENDED FROM NEAR JOHNSON TO SCOTT CITY TO HILL CITY...WITH A CONTINUED PUSH SOUTH AND EAST. AS OF 18Z...THE ENVIRONMENTAL SETTING ALONG AND AHEAD OF THE FRONT WAS MARGINALLY UNSTABLE WITH SBCAPE AROUND 1500 J/KG...MAINLY ACROSS FAR SOUTHWESTERN KANSAS. PER SPC MESOSCALE ANALYSIS PAGE AT 18Z, 0-6KM AGL BULK SHEAR VALUES OF AROUND 35 KNOTS WITH NEARLY 90-DEGREE VEERING IN THE 850-500MB LAYER SUPPORT ORGANIZED CONVECTIVE STRUCTURES, INCLUDING SUPERCELLS. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 119 PM CDT SAT JUN 8 2013 CONVECTIVE MODE, DURATION, SEVERITY ARE THE MAIN CHALLENGE IN THE "TONIGHT" PERIOD OF THE FORECAST. JUST ABOUT ALL SHORT-TERM HIGH RESOLUTION MODELS SHOW CONVECTIVE DEVELOPMENT AT OR SHORTLY AFTER 20Z ALONG THE FRONT. THE HRRR DOES SUGGEST INDIVIDUAL COHERENT CELLS (PERHAPS SUPERCELLS) AS THE INITIAL MODE. THE PREVIOUS FORECAST CONCERN FOR HAIL UP TO GOLFBALL SIZE IN THE STRONGEST STORM STILL LOOKS JUSTIFIED. ONCE AN ESTABLISHED COLD POOL IS GENERATED...THE GROWTH UPSCALE WILL LEAD TO A TRANSITION IN SEVERE THREAT FROM ONE OF LARGE HAIL TO ONE OF DAMAGING STRAIGHT LINE WINDS. WHEN AND WHERE EXACTLY THIS WILL TRANSITION IS STILL UNCERTAIN...BUT BY 00Z THE GENERAL THINKING IS THAT CONVECTIVE MODE SHOULD BE QUASI-LINEAR...ESPECIALLY IN THE CENTRAL AND SOUTH-CENTRAL KANSAS PORTION OF THE DDC FORECAST AREA (ALONG AND EAST OF HIGHWAY 183). FARTHER SOUTH AND WEST...SUPERCELL STRUCTURES MAY LAST A BIT LONGER WITH SLIGHTLY A BIT MORE CAPPING TO KEEP CONVECTION FROM GROWING UPSCALE TOO QUICKLY. NO CHANGE WAS REQUIRED IN THE POP/WX GRIDS WITH 60-70 POPS STILL QUITE REASONABLE. STRONG/SEVERE CONVECTION SHOULD CLEAR THE ENTIRE DDC FORECAST AREA (EAST AND SOUTH OF BARBER, COMANCHE, PRATT COUNTIES) DURING THE 01-03Z TIME FRAME AS THE FRONT CONTINUES ITS PUSH SOUTH AND EAST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 404 AM CDT SAT JUN 8 2013 ALTHOUGH THERE ARE SOME MINOR DIFFERENCES IN SYNOPTIC SCALE DETAILS, CONFIDENCE IS HIGH THAT SUBTROPICAL HIGH PRESSURE WILL BUILD OVER THE CENTRAL AND SOUTHERN PLAINS BY MONDAY AND WILL PERSIST THROUGH THE WEEK. VERY WARM AIR IN THE MID LEVELS OF THE ATMOSPHERE WILL SPREAD FROM THE ROCKIES TO THE CENTRAL PLAINS SUNDAY NIGHT, AND H7 TEMPERATURES AOA +15C ARE LIKELY TO PREVAIL FROM MONDAY THROUGH SATURDAY. SHALLOW LOW LEVEL MOISTURE WILL MIX OUT EACH DAY, AND THE POTENTIAL FOR DEVELOPING ANY THUNDERSTORMS IS QUITE LOW. TEMPERATURES NEAR OR ABOVE 100 DEGREES ARE LIKELY ALMOST EVERY DAY. ALTHOUGH WIDESPREAD RAINFALL SATURDAY AND SATURDAY EVENING WILL HELP TO KEEP VEGETATION GREEN FOR A FEW DAYS, VERY LOW RELATIVE HUMIDITY VALUES AND HIGH TEMPERATURES WILL DRY OUT PLANTS QUICKLY, AND EVEN PLANTS THAT APPEAR TO BE GREEN MAY HAVE LOW ENOUGH MOISTURE CONTENT TO CARRY FIRE BY MID WEEK. TROPICAL THUNDERSTORMS REMAIN ACTIVE FROM THE ARABIAN SEA TO THE MARITIME CONTINENT, BUT THERE IS LITTLE EVIDENCE OF A COHERENT EASTWARD PROPAGATING CLUSTER. THE NUMERICAL MODELS ARE IN REASONABLE AGREEMENT THAT A WEAK MADDEN JULIAN OSCILLATION MAY DEVELOP IN THE EASTERN INDIAN OCEAN AND MARITIME CONTINENT BY 12 JUNE, BUT CONFIDENCE IS LOW. RELATIVE ATMOSPHERIC ANGULAR MOMENTUM IS MORE THAN TWO STANDARD DEVIATIONS BELOW CLIMATOLOGY. MOUNTAIN TORQUE HAS TRENDED MORE POSITIVE IN RECENT DAYS, AND THE RELATIVE ANGULAR MOMENTUM TENDENCY HAS BECOME SLIGHTLY POSITIVE. THE ATMOSPHERE APPEARS TO BE LIKELY TO PERSIST IN PHASE 2-3 OF THE BERRY/WEICKMANN PHASE SPACE DIAGRAM, WHICH FAVORS ANTICYCLONIC FLOW ACROSS THE SOUTHERN UNITED STATES. SEA SURFACE TEMPERATURES CONTINUE TO BE ANOMALOUSLY WARM IN THE NORTHERN PACIFIC BETWEEN 40N AND 50N AND 130W-170W, AND THIS WARM POOL SHOWS LITTLE SIGN OF WEAKENING. WITH THE ANOMALOUS WARMTH, THE ATMOSPHERE LIKELY WILL FAVOR RIDGING IN THE PACIFIC WITH DOWNSTREAM TROUGHING NEAR THE WEST COAST OF NORTH AMERICA AND RIDGING IN THE CENTRAL PART OF THE COUNTRY. THE STRONG SUBTROPICAL RIDGE FROM THE SOUTHWESTERN UNITED STATES ACROSS THE CENTRAL AND SOUTHERN PLAINS MAY BE A COMMON FEATURE THIS SUMMER. SUNDAY WILL BE MILD WITH NORTHWEST LOW LEVEL FLOW AND TEMPERATURES ONLY A FEW DEGREES ABOVE CLIMATOLOGY AS THE DEEP TROUGH CURRENTLY MOVING INTO WYOMING CLOSES OFF OVER IOWA. PRESSURES WILL BEGIN TO FALL IN THE LEE OF THE ROCKIES SUNDAY AFTERNOON AS WESTERLY FLOW INCREASES ACROSS THE ROCKIES, AND THE FRONT THAT PASSES THROUGH WESTERN KANSAS SATURDAY AFTERNOON AND EVENING WILL BEGIN TO LIFT BACK NORTH AS A WARM FRONT. THE GFS IS MUCH MORE AGGRESSIVE WITH DEVELOPING THUNDERSTORMS IN THE WARM ADVECTION NORTH OF THE WARM FRONT THAN THE ECMWF OR GEM. H7 TEMPERATURES WILL WARM DURING THE NIGHT AS THE EML SPREADS INTO WESTERN KANSAS, AND CONFIDENCE IS LOW THAT THERE WILL BE MUCH THUNDERSTORM DEVELOPMENT. THE BEST OPPORTUNITY FOR THUNDERSTORM DEVELOPMENT WILL BE IN SOUTH CENTRAL KANSAS NEAR THE EDGE OF THE EML AS THE LOW LEVEL JET ENHANCES WARM AIR ADVECTION. POPS IN THE 10-15 PERCENT RANGE SEEMED APPROPRIATE GIVEN THE LEVEL OF UNCERTAINTY. THE WARM FRONT WILL CONTINUE TO LIFT NORTH ON MONDAY AND SHOULD EXTEND NEAR A LINE FROM GOODLAND TO COLDWATER BY MONDAY AFTERNOON. SOME POOLING OF MOISTURE WILL OCCUR ALONG THE BOUNDARY, AND AN ISOLATED THUNDERSTORM OR TWO MAY FORM LATE IN THE AFTERNOON EVEN WITH VERY WARM AIR ALOFT. THE FRONT WILL CONTINUE TO MOVE NORTHEAST MONDAY NIGHT AND A STRONG EML WILL PRECLUDE ANY NOCTURNAL CONVECTION. A WEAK UPPER LEVEL CYCLONE WEST OF BAJA CALIFORNIA WILL MOVE OVER THE CENTRAL UNITED STATES RIDGE TUESDAY, AND A SURFACE CYCLONE WILL DEEPEN IN NORTHEAST COLORADO. GUSTY SOUTHWEST WINDS AND H8 TEMPERATURES FROM 30C TO 35C WILL FAVOR WIDESPREAD MAXIMUM TEMPERATURES WELL ABOVE 100 DEGREES. AS THE UPPER LEVEL TROUGH RIPPLES EAST TOWARD THE UPPER MIDWEST, A WEAK PACIFIC COLD FRONT WILL MOVE ACROSS WESTERN KANSAS WEDNESDAY MORNING. TEMPERATURES WEDNESDAY WILL BE ONLY SLIGHTLY BELOW VALUES ON TUESDAY AND STILL SHOULD REACH 100 DEGREES ACROSS MUCH OF SOUTHWEST KANSAS. HEIGHTS WILL RISE AGAIN ON THURSDAY AND THE HEAT WILL CONTINUE FRIDAY AND SATURDAY. AN UPPER LEVEL TROUGH WILL MOVE ACROSS SOUTHERN CANADA FRIDAY AND SATURDAY, AND A COLD FRONT SHOULD PROGRESS ACROSS KANSAS ON SATURDAY WITH SLIGHTLY COOLER TEMPERATURES BY SUNDAY. MID LEVELS OF THE ATMOSPHERE WILL BE SO WARM THAT THUNDERSTORMS ARE NOT LIKELY WITH THE FRONT, BUT POST FRONTAL THUNDERSTORMS MAY OCCUR AS MOISTURE POOLS BEHIND THE FRONT AND THE EML WEAKENS SATURDAY NIGHT AND SUNDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1254 PM CDT SAT JUN 8 2013 A COLD FRONT WILL MOVE ACROSS THE SOUTHWEST AND WEST-CENTRAL KANSAS REGION THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED IN VICINITY OF HYS, GCK, AND DDC TERMINALS LATE THIS AFTERNOON THROUGH EARLY EVENING (ROUGHLY 22Z THROUGH 01Z TIME FRAME). BEHIND THE FRONT...NORTH TO NORTHEAST WINDS OF 15 TO 20 KNOTS IS EXPECTED INITIALLY...WITH A DECREASE IN WIND SPEED AFTER 06Z SUNDAY. && .PRELIMINARY POINT TEMPS/POPS... DDC 60 91 63 99 / 40 0 0 10 GCK 58 91 63 100 / 30 0 0 10 EHA 59 93 67 100 / 30 0 10 0 LBL 61 93 66 101 / 40 0 10 0 HYS 58 87 60 94 / 20 10 0 10 P28 63 89 66 95 / 70 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...UMSCHEID SHORT TERM...UMSCHEID LONG TERM...RUTHI AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1257 PM CDT SAT JUN 8 2013 .UPDATE... ISSUED AT 621 AM CDT SAT JUN 8 2013 SOME ELEVATED SHOWERS HAVE FORMED ACROSS NORTHEAST KS NEAR THE NEB STATE LINE. THIS LOOKS TO BE DRIVEN BY ISENTROPIC LIFT AS NOTED ON THE RAP AND NAM PROGS. INSTABILITY PER THE MID LEVEL LAPSE RATES REMAINS LIMITED AND THIS SEEMS TO BE CONFIRMED BY THE SHALLOW NATURE OF THE SHOWERS. THINK THIS WILL BE SHORT LIVED WITH ONLY A SLIGHT CHANCE FOR UPSCALE DEVELOPMENT. THE MAIN CONVECTIVE EVENT CONTINUES TO AFFECT THE AREA BY THE EARLY AFTERNOON AS A SHORTWAVE CONTINUES TO DIG SOUTHEAST FROM WY INTO THE NEBRASKA PANHANDLE AS SEEN ON THE 11Z WATER VAPOR IMAGERY. MOST SHORT RANGE MODEL DATA SHOWS A LINEAR CONVECTIVE SYSTEM MOVING INTO OR DEVELOPING OVER NORTH CENTRAL KS BETWEEN 1 AND 3 PM. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CDT SAT JUN 8 2013 08Z WATER VAPOR IMAGERY SHOWS NORTHWEST FLOW PERSISTING FROM THE NORTHERN ROCKIES TO THE PLAINS WITH A SHORTWAVE BEGINNING TO DIG SOUTHEAST INTO WY. THIS WAVE IS ALREADY CAUSING CONVECTION ACROSS EASTERN WY. AT THE SURFACE...A TROUGH OF LOW PRESSURE HAS GRADUALLY BEEN DEEPENING ALONG THE LEE OF THE CENTRAL ROCKIES. FOR TODAY AND TONIGHT...ALL OF THE MODELS SEEM TO BE IN GOOD AGREEMENT WITH THE SHORTWAVE OVER WY MOVING ACROSS NORTHEAST KS. WITH THE LEE SURFACE TROUGH CAUSING SOUTHERLY WINDS TO PERSIST AND INCREASE THROUGH THE DAY...DEEP LAYER MOISTURE IS EXPECTED TO INCREASE WHILE SURFACE DEW POINTS INCREASING TO AROUND 60. ADDITIONALLY THE SHORTWAVE SHOULD BRING A MODIFIED PACIFIC COLD FRONT INTO NORTH CENTRAL KS BY THIS AFTERNOON. SO CONFIDENCE IS GOOD THAT THERE WILL BE CONVECTION MOVING ACROSS THE AREA THIS AFTERNOON AND THIS EVENING...AND HAVE BUMPED POPS UP CLOSE TO 90 PERCENT. WITH RESPECT TO SEVERE WEATHER...MODEL PROGS CONTINUE TO BE RATHER MODEST ON CAPE WITH MID LEVEL LAPSE RATES NOT MUCH STEEPER THAN THE MOIST ADIABAT. THE CONCERN IS THE LARGE LOW LEVEL HODOGRAPHS WITH 0-1 BULK SHEER VALUES ON THE ORDER OF 30 TO 40 KTS. MODELS SHOW THE COLLOCATION OF THE LOWEST LCL HEIGHTS AND LOW LEVEL SHEER TO BE ALONG HWY 36 AND TO THE NORTH. SO IF THERE WERE ANY DISCRETE STORMS... THERE COULD BE AN OUTSIDE CHANCE FOR A TORNADO. HOWEVER WITH STORMS ONGOING UPSTREAM WITH THE SHORTWAVE...WE MAY BE MORE INCLINED TO HAVE SOME SORT OF MCS MOVE INTO NORTH CENTRAL KS BY MID AFTERNOON AND MOVE ACROSS NORTHEAST AND EAST CENTRAL KS THROUGH THE EARLY EVENING. WITH THIS IN MIND...THINK LARGE HAIL AND DAMAGING WINDS MAY END UP BEING THE MAIN CONCERNS. STORMS SHOULD BE PROGRESSIVE WITH THE WAVE WAITING UNTIL IT REACHES THE MO RIVER TO BEGIN TO CLOSE. SO MODELS SUGGEST THE BEST FORCING TO MOVE ACROSS THE FORECAST AREA DURING THE LATER AFTERNOON AND EVENING. WITH THIS IN MIND AND EXPECTING MAINLY AN MCS FOR STORM MODE...THINK STORMS WILL MOVE OFF INTO MO AROUND MIDNIGHT AND HAVE POPS DECREASING AFTER MIDNIGHT. HIGHS TODAY SHOULD BE A COUPLE DEGREES WARMER THAN YESTERDAY WITH BETTER LOW LEVEL WARM AIR ADVECTION OCCURRING THROUGH THE DAY. THERE DOES NOT APPEAR TO BE A GREAT DEAL OF COLD AIR BEHIND THE FRONT TONIGHT. SO LOWS ARE EXPECTED TO ONLY FALL INTO THE UPPER 50S AND LOWER 60S. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 339 AM CDT SAT JUN 8 2013 BEHIND THE MAIN COMPLEX OF STORMS ON SATURDAY EVENING...MAY STILL SEE SOME POST FRONTAL ELEVATED SHOWERS LINGER INTO SUNDAY MORNING OVER EAST CENTRAL KS. OTHERWISE THE STACKED CYCLONE EXITS TOWARDS THE GREAT LAKES...WITH SUBSIDENCE BEHIND THE WAVE ALLOWING SKIES TO CLEAR OUT FOR THE AFTERNOON. AS THE FRONT SHIFTS INTO OKLAHOMA BY THE AFTERNOON...00Z GFS IS THE OUTLIER IN TRYING TO LIFT THE BOUNDARY NORTHWARD AS A WARM FRONT WITH SCT CONVECTION POSSIBLE JUST SOUTH OF THE CWA OVERNIGHT SUNDAY. OPTED TO LEAVE OUT ANY PRECIP MENTION FOR NOW AS BEST FORCING STAYS OVER FAR SOUTHERN KS. ZONAL FLOW SETS UP ACROSS THE REGION ON MONDAY AS A SFC LEE TROUGH DEEPENS JUST EAST OF THE ROCKIES ON MONDAY EVENING. GFS IS MORE PROGRESSIVE AND FURTHER EAST WITH THE TROUGH DEVELOPMENT COMPARED TO ECMWF. STILL A SLIGHT POSSIBILITY WE COULD SEE OVERNIGHT CONVECTION DEVELOP AND TRACK EASTWARD THROUGH THE AREA. AS THIS SURFACE TROF LIFTS NORTHEAST TUESDAY AND WEDNESDAY...DECENT SOUTHWEST FLOW AND 12Z H85 TEMPS NEAR 28C SUGGEST WE COULD SEE A TASTE OF SUMMER THROUGHOUT THE WEEK. HIGHS WILL EASILY MIX DOWN TO THE UPPER 80S AND LOW 90S. OPTED TO GO A DEGREE OR TWO WARMER...HOWEVER INTERESTING TO NOTE GFS MOS GUIDANCE WAS THE WARMEST SCENARIO WITH MIXING UP TO 850 MB TRANSLATING TO THE MIDDLE 90S ON TUES AND WED SO MAY NEED TO WATCH TO SEE IF SHORT TERM GUIDANCE TRENDS THIS WAY. UPPER RIDGE AXIS GAINS CONTROL BY MID TO LATE WEEK WITH CLEAR SKIES...AMPLE WARM ADVECTION...AND HIGHS STEADY IN THE 80S TO LOW 90S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1253 PM CDT SAT JUN 8 2013 EXPECT VFR CONDITIONS THROUGH 00Z SUN AT THE TAF SITES. SOUTH WINDS WILL CONTINUE AT 14 TO 18 KTS WITH GUSTS OF 24 TO 29 KTS THROUGH THE AFTERNOON HOURS. A LINE OF THUNDERSTORMS WILL MOVE EAST ACROSS THE TAF SITES THIS EVENING BRINGING GUSTY WINDS AND BRIEF HEAVY RAINFALL. MAY SEE SOME MVFR CEILINGS AND VISIBILITIES WITHIN THE LINE OF THUNDERSTORMS. ONCE THE THUNDERSTORMS PASS TO THE EAST LATE THIS EVENING...THEN CONDITIONS SHOULD BECOME VFR AGAIN...WITH WESTERLY SURFACE WINDS. GARGAN && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WOLTERS SHORT TERM...WOLTERS LONG TERM...BOWEN AVIATION...GARGAN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
622 AM CDT SAT JUN 8 2013 .UPDATE... ISSUED AT 621 AM CDT SAT JUN 8 2013 SOME ELEVATED SHOWERS HAVE FORMED ACROSS NORTHEAST KS NEAR THE NEB STATE LINE. THIS LOOKS TO BE DRIVEN BY ISENTROPIC LIFT AS NOTED ON THE RAP AND NAM PROGS. INSTABILITY PER THE MID LEVEL LAPSE RATES REMAINS LIMITED AND THIS SEEMS TO BE CONFIRMED BY THE SHALLOW NATURE OF THE SHOWERS. THINK THIS WILL BE SHORT LIVED WITH ONLY A SLIGHT CHANCE FOR UPSCALE DEVELOPMENT. THE MAIN CONVECTIVE EVENT CONTINUES TO AFFECT THE AREA BY THE EARLY AFTERNOON AS A SHORTWAVE CONTINUES TO DIG SOUTHEAST FROM WY INTO THE NEBRASKA PANHANDLE AS SEEN ON THE 11Z WATER VAPOR IMAGERY. MOST SHORT RANGE MODEL DATA SHOWS A LINEAR CONVECTIVE SYSTEM MOVING INTO OR DEVELOPING OVER NORTH CENTRAL KS BETWEEN 1 AND 3 PM. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CDT SAT JUN 8 2013 08Z WATER VAPOR IMAGERY SHOWS NORTHWEST FLOW PERSISTING FROM THE NORTHERN ROCKIES TO THE PLAINS WITH A SHORTWAVE BEGINNING TO DIG SOUTHEAST INTO WY. THIS WAVE IS ALREADY CAUSING CONVECTION ACROSS EASTERN WY. AT THE SURFACE...A TROUGH OF LOW PRESSURE HAS GRADUALLY BEEN DEEPENING ALONG THE LEE OF THE CENTRAL ROCKIES. FOR TODAY AND TONIGHT...ALL OF THE MODELS SEEM TO BE IN GOOD AGREEMENT WITH THE SHORTWAVE OVER WY MOVING ACROSS NORTHEAST KS. WITH THE LEE SURFACE TROUGH CAUSING SOUTHERLY WINDS TO PERSIST AND INCREASE THROUGH THE DAY...DEEP LAYER MOISTURE IS EXPECTED TO INCREASE WHILE SURFACE DEW POINTS INCREASING TO AROUND 60. ADDITIONALLY THE SHORTWAVE SHOULD BRING A MODIFIED PACIFIC COLD FRONT INTO NORTH CENTRAL KS BY THIS AFTERNOON. SO CONFIDENCE IS GOOD THAT THERE WILL BE CONVECTION MOVING ACROSS THE AREA THIS AFTERNOON AND THIS EVENING...AND HAVE BUMPED POPS UP CLOSE TO 90 PERCENT. WITH RESPECT TO SEVERE WEATHER...MODEL PROGS CONTINUE TO BE RATHER MODEST ON CAPE WITH MID LEVEL LAPSE RATES NOT MUCH STEEPER THAN THE MOIST ADIABAT. THE CONCERN IS THE LARGE LOW LEVEL HODOGRAPHS WITH 0-1 BULK SHEER VALUES ON THE ORDER OF 30 TO 40 KTS. MODELS SHOW THE COLLOCATION OF THE LOWEST LCL HEIGHTS AND LOW LEVEL SHEER TO BE ALONG HWY 36 AND TO THE NORTH. SO IF THERE WERE ANY DISCRETE STORMS... THERE COULD BE AN OUTSIDE CHANCE FOR A TORNADO. HOWEVER WITH STORMS ONGOING UPSTREAM WITH THE SHORTWAVE...WE MAY BE MORE INCLINED TO HAVE SOME SORT OF MCS MOVE INTO NORTH CENTRAL KS BY MID AFTERNOON AND MOVE ACROSS NORTHEAST AND EAST CENTRAL KS THROUGH THE EARLY EVENING. WITH THIS IN MIND...THINK LARGE HAIL AND DAMAGING WINDS MAY END UP BEING THE MAIN CONCERNS. STORMS SHOULD BE PROGRESSIVE WITH THE WAVE WAITING UNTIL IT REACHES THE MO RIVER TO BEGIN TO CLOSE. SO MODELS SUGGEST THE BEST FORCING TO MOVE ACROSS THE FORECAST AREA DURING THE LATER AFTERNOON AND EVENING. WITH THIS IN MIND AND EXPECTING MAINLY AN MCS FOR STORM MODE...THINK STORMS WILL MOVE OFF INTO MO AROUND MIDNIGHT AND HAVE POPS DECREASING AFTER MIDNIGHT. HIGHS TODAY SHOULD BE A COUPLE DEGREES WARMER THAN YESTERDAY WITH BETTER LOW LEVEL WARM AIR ADVECTION OCCURRING THROUGH THE DAY. THERE DOES NOT APPEAR TO BE A GREAT DEAL OF COLD AIR BEHIND THE FRONT TONIGHT. SO LOWS ARE EXPECTED TO ONLY FALL INTO THE UPPER 50S AND LOWER 60S. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 339 AM CDT SAT JUN 8 2013 BEHIND THE MAIN COMPLEX OF STORMS ON SATURDAY EVENING...MAY STILL SEE SOME POST FRONTAL ELEVATED SHOWERS LINGER INTO SUNDAY MORNING OVER EAST CENTRAL KS. OTHERWISE THE STACKED CYCLONE EXITS TOWARDS THE GREAT LAKES...WITH SUBSIDENCE BEHIND THE WAVE ALLOWING SKIES TO CLEAR OUT FOR THE AFTERNOON. AS THE FRONT SHIFTS INTO OKLAHOMA BY THE AFTERNOON...00Z GFS IS THE OUTLIER IN TRYING TO LIFT THE BOUNDARY NORTHWARD AS A WARM FRONT WITH SCT CONVECTION POSSIBLE JUST SOUTH OF THE CWA OVERNIGHT SUNDAY. OPTED TO LEAVE OUT ANY PRECIP MENTION FOR NOW AS BEST FORCING STAYS OVER FAR SOUTHERN KS. ZONAL FLOW SETS UP ACROSS THE REGION ON MONDAY AS A SFC LEE TROUGH DEEPENS JUST EAST OF THE ROCKIES ON MONDAY EVENING. GFS IS MORE PROGRESSIVE AND FURTHER EAST WITH THE TROUGH DEVELOPMENT COMPARED TO ECMWF. STILL A SLIGHT POSSIBILITY WE COULD SEE OVERNIGHT CONVECTION DEVELOP AND TRACK EASTWARD THROUGH THE AREA. AS THIS SURFACE TROF LIFTS NORTHEAST TUESDAY AND WEDNESDAY...DECENT SOUTHWEST FLOW AND 12Z H85 TEMPS NEAR 28C SUGGEST WE COULD SEE A TASTE OF SUMMER THROUGHOUT THE WEEK. HIGHS WILL EASILY MIX DOWN TO THE UPPER 80S AND LOW 90S. OPTED TO GO A DEGREE OR TWO WARMER...HOWEVER INTERESTING TO NOTE GFS MOS GUIDANCE WAS THE WARMEST SCENARIO WITH MIXING UP TO 850 MB TRANSLATING TO THE MIDDLE 90S ON TUES AND WED SO MAY NEED TO WATCH TO SEE IF SHORT TERM GUIDANCE TRENDS THIS WAY. UPPER RIDGE AXIS GAINS CONTROL BY MID TO LATE WEEK WITH CLEAR SKIES...AMPLE WARM ADVECTION...AND HIGHS STEADY IN THE 80S TO LOW 90S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 621 AM CDT SAT JUN 8 2013 CONFIDENCE IN THUNDERSTORMS AFFECTING THE TERMINALS IS HIGH DUE TO GOOD CONSENSUS AND CONTINUITY IN THE SHORT RANGE MODEL DATA. CURIOUSLY THE OBJECTIVE MOS GUIDANCE DOES NOT SHOW MUCH FOR RESTRICTIONS WITH ONLY VERY LOW PROBABILITIES FOR MVFR CIGS AND VSBY. FORECAST SOUNDINGS FROM THE RAP AND NAM ALSO SUGGEST CIGS COULD STAY ABOVE 3KFT. THEREFORE HAVE NOT BROUGHT ANY MVFR CIGS IN YET AND WILL LET THE NEXT SHIFT MONITOR TRENDS. DID BRING SOME MVFR VSBY INTO THE TERMINALS AS THE STORMS MOVE THROUGH. TIMINGS IS A BEST GUESS BASED OFF OF THE ARW/HRRR/RAP13/NAM CONSENSUS OF CONVECTIVE TRENDS...WHICH APPEARS TO BE AROUND 22Z FOR MHK AND 01Z FOR TOP AND FOE. && .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...WOLTERS SHORT TERM...WOLTERS LONG TERM...BOWEN AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS JACKSON KY
231 PM EDT SAT JUN 8 2013 .UPDATE... ISSUED AT 1235 PM EDT SAT JUN 8 2013 AS SUBTLE SHORTWAVE CONTINUES TO MOVE OVER CENTRAL AND EASTERN KY...DESPITE LARGE CAPPING ENVIRONMENT...DAYTIME HEATING AND MOISTURE HAS HELPED TO SPAWN SOME ISOLATED/SCATTERED LIGHT SHOWERS ACROSS THE EASTERN HALF OF THE STATE. EXPECT SHOWER DEVELOPMENT TO CONTINUE ACROSS THE CWA OVER THE NEXT FEW HOURS...REMAINING FAIRLY ISOLATED IN NATURE...BEFORE SHORTWAVE CONTINUES TO LOSE INTENSITY AND LIFT OUT OF THE REGION. AS A RESULT...WENT AHEAD AND UPDATED POPS TO REFLECT THIS OBSERVATION. PREVIOUS FORECAST SHOWED ISOLATED POPS BEGINNING TO LIFT OUT IN THE NEXT COUPLE OF HOURS...HOWEVER...DECIDED TO INCLUDE ISOLATED POPS ACROSS MUCH OF THE CWA THROUGH ABOUT 22Z BEFORE LIFTING TO THE NE. THIS WILL COVER ANY ISOLATED SHOWERS THAT ARE CURRENTLY POPPING UP AS WELL AS ANY FUTURE SHOWERS/TS THAT MAY INCUR LATER IN THE AFTERNOON DESPITE THE CAPPING IN PLACE. ALSO...WITH VERY LITTLE SHEAR TO WORK WITH...EXPECT WHAT DOES DEVELOP TO BE PULSY IN NATURE AND FAIRLY SHORT LIVED. OTHERWISE...ONGOING FORECAST SEEMS TO BE QUITE REASONABLE...SO DO NOT EXPECT ANY CRUCIAL UPDATES /OUTSIDE OF SHOWER DEVELOPMENT/ UNTIL AFTERNOON FORECAST PACKAGE. UPDATE ISSUED AT 751 AM EDT SAT JUN 8 2013 NO MAJOR CHANGES TO THE FORECAST. GFS 06Z MODEL GUIDANCE CAME IN WITH SLIGHTLY HIGHER WITH POPS FOR TODAY...20 PERCENT. RADAR MOSAIC STILL SHOWING AN OCCASIONAL POP UP FURTHER TO OUR WEST. THOUGHTS ARE THAT DIURNAL HEATING WILL ONLY HELP ADDITIONAL SHOWERS...THUNDERSTORMS TO FIRE LATER TODAY. SHORT WAVE RIDGING WILL BEGIN TO BUILD IN OVER THE AREA TODAY...WHILE UPPER LEVEL TROUGH LIFTS TO THE NORTHEAST. TODAYS FORECAST CHALLENGE WILL BE HOW STRONG WILL THE RESULTING DEVELOPING CAP BE AND HOW SOON WILL IT BEGIN TO DAMPEN CONVECTION GENERATED BY RELATIVELY WEAK SHORTWAVE ENERGY PASSING THROUGH THE AREA. IN GENERAL FORECAST SOUNDINGS SHOW THE CAP AT OR ABOVE 10 KFT THROUGH 18Z TO 21Z. 06Z NAM/10Z RAP FORECAST SOUNDINGS SUGGEST THE CAP WILL NOT BE STRONG ENOUGH TO PREVENT CONVECTION...BUT POSSIBLY SLOW GROWTH OF CELLS. ALSO...NAM/RAP SOUNDINGS DO NOT INHIBIT GROWTH ENOUGH TO PREVENT THE POTENTIAL OF THUNDER. ON THE OTHER HAND THE GFS ADVERTISES A STRONGER CAP...NOT STRONG ENOUGH TO PREVENT SHOWERS FROM FIRING...BUT ENOUGH TO KEEP THUNDER OUT OF THE FORECAST. HENSE THE LOWER POP GUIDANCE FROM THE GFS...SLIGHT VERSUS CHANCE FROM THE NAM GUIDANCE. THE HRRR SUGGEST AN UPTICK IN CONVECTION AFTER ABOUT 15Z OR 16Z...BEING MORE NUMEROUS OR SCATTERED IN NATURE. BUT THE HRRR USUALLY HAS A DIFFICULT TIME WITH CONVECTIVE INITIATION. DECIDED TO MAINTAIN OUR ORIGINAL SLIGHT POP...ISOLD COVERAGE THROUGH THE DAY AND ALSO KEPT A MENTION OF THUNDER BASED ON THE CONSENSUS OF THE NAM AND RAP SOUNDINGS. UPDATED GRIDS TO REFLECT MOST RECENT HOURLY OBS. NO CHANGES TO THE ZONE PACKAGE ATTM...THOUGH MOSTLY CLOUDY MIGHT BE A BETTER DESCRIPTION TO SKY COVER THAN THE CURRENT PC WORDING...AT LEAST THROUGH THE FIRST HALF OF THE DAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 359 AM EDT SAT JUN 8 2013 LIGHT RAIN SHOWERS OVER THE FAR SOUTHEAST WILL CONTINUE TO PUSH OFF TO THE EAST EARLY THIS MORNING...MOVING COMPLETELY OUT OF THE AREA WELL BEFORE SUNRISE. OTHERWISE...BAND OF BKN MID LEVEL CIGS ALONG WITH ISOLD SHOWERS...OR PATCHY SPRINKLES WILL CONTINUE TO PROGRESS SLOWLY EASTWARD ACROSS THE COMMONWEALTH FROM THE WEST THIS MORNING. UPPER LEVEL DISTURBANCE RESPONSIBLE FOR THIS ACTIVITY MAY GENERATE MORE WIDESPREAD CONVECTION LATER TODAY...ESPECIALLY IF FAVORABLE DIURNAL HEATING CAN BE TAPPED INTO. HOWEVER SHORTWAVE RIDGING WILL BEGIN BUILDING OVER THE REGION LATE THIS AFTERNOON...EFFECTIVELY STRENGTHENING A MID LEVEL CAP AND SHUTTING DOWN CONVECTION FAIRLY QUICKLY BY LATE AFTERNOON. FOCUS THEN MOVES TO OUR NEXT WEATHER MAKER...LOW PRESSURE SYSTEM MOVING OUT OF THE PLAINS AND INTO THE OHIO VALLEY BY LATE SUNDAY NIGHT INTO MONDAY. THIS NEXT SYSTEM WILL PROVIDE A MUCH BETTER CHANCE AT SOME RAINFALL. INCREASE POPS FOR TODAY AND SUNDAY AS WELL...FOLLOWING TRENDS IN MODELS AND MODEL GUIDANCE. FOR TEMPS JUST MADE SOME MINOR TWEAKS TOWARDS LATEST MODEL BLENDS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 230 PM EDT SAT JUN 8 2013 MODELS BEGIN MONDAY AFTERNOON WITH A 50H CLOSED LOW OVER THE WRN OHIO VALLEY. THE SFC REFLECTION OF THIS CLOSED LOW HAS A CENTER OF CIRCULATION IN NRN IND WITH A COLD FRONT CROSSING MIDDLE KY. NUMEROUS SHOWERS AND THUNDERSTORMS WILL PRECEDE THE FRONT WITH SCT SHOWERS LINGERING INTO EARLY TUE. HIGH PRESSURE BUILDS INTO THE REGION QUICKLY WITH HIGH TEMPS ON MON AND TUE IN THE UPPER 70S AND THEN CLIMBING QUICKLY INTO THE MID 80S FOR WED/THU. WITH THE 50H RIDGE WELL ESTABLISHED IN THE PLAINS THE NEXT DISTURBANCE WILL DROP DOWN THE ERN SIDE OF THE RIDGE INTO THE OHIO VALLEY TO BRING A QUICK SHOT OF RAIN TO THE AREA ON THU AFTERNOON AND CONTINUING INTO LATE FRI. THE PCPN WILL ALSO DROP HIGH TEMPS INTO THE LOWR 80S FOR FRI. THE UPPER FLOW WILL THEN BECOME MORE ZONAL FOR THE WEEKEND AND SHOULD CARRY MOST DISTURBANCES ACROSS THE GREAT LAKES WITH LITTLE PCPN FOR KENTUCKY AS HIGH TEMPS CLIMB BACK INTO THE MIDDLE AND UPPER 80S FOR SAT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 224 PM EDT SAT JUN 8 2013 MAIN FORECAST CONCERN WILL BE THE FOG THAT DEVELOPS IN MUCH OF THE VALLEY REGIONS OVERNIGHT. BEFORE THAT POINT...ISOLATED SHOWERS CURRENTLY ON RADAR HAVE THE POSSIBILITY TO AFFECT TAF SITES OVER THE NEXT FEW HOURS...THOUGH LITTLE IN THE WAY OF IMPACTS IS EXPECTED. SMALL SHORTWAVE ENERGY THAT IS PRODUCING THESE SHOWERS WILL CONTINUE TO LIFT OFF NORTHEAST...WITH EXPECTED CLEARING AS DAYTIME HEATING SUBSIDES THIS EVENING. FOG WILL THEN SET IN DURING THE OVERNIGHT...WITH GUIDANCE SHOWING THE MOST IMPACTS AT KSME WHERE IFR CONDITIONS ARE POSSIBLE. LEANED A LITTLE BIT MORE OPTIMISTICALLY FOR KJKL AND KLOZ...THOUGH SOME MVFR VIS MAY NOT BE OUT OF THE QUESTION. AS WE HEAD INTO TOMORROW...FOG WILL LIFT IN THE MORNING...BUT NEXT SHORTWAVE IS POISED TO IMPACT MUCH OF THE REGION BY EARLY AFTERNOON. EXACT TIMING AND LOCATION OF SHOWER DEVELOPMENT IS UNCERTAIN AT THIS TIME. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JMW SHORT TERM...RAY LONG TERM...DUSTY AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
227 PM EDT SAT JUN 8 2013 .UPDATE... ISSUED AT 1235 PM EDT SAT JUN 8 2013 AS SUBTLE SHORTWAVE CONTINUES TO MOVE OVER CENTRAL AND EASTERN KY...DESPITE LARGE CAPPING ENVIRONMENT...DAYTIME HEATING AND MOISTURE HAS HELPED TO SPAWN SOME ISOLATED/SCATTERED LIGHT SHOWERS ACROSS THE EASTERN HALF OF THE STATE. EXPECT SHOWER DEVELOPMENT TO CONTINUE ACROSS THE CWA OVER THE NEXT FEW HOURS...REMAINING FAIRLY ISOLATED IN NATURE...BEFORE SHORTWAVE CONTINUES TO LOSE INTENSITY AND LIFT OUT OF THE REGION. AS A RESULT...WENT AHEAD AND UPDATED POPS TO REFLECT THIS OBSERVATION. PREVIOUS FORECAST SHOWED ISOLATED POPS BEGINNING TO LIFT OUT IN THE NEXT COUPLE OF HOURS...HOWEVER...DECIDED TO INCLUDE ISOLATED POPS ACROSS MUCH OF THE CWA THROUGH ABOUT 22Z BEFORE LIFTING TO THE NE. THIS WILL COVER ANY ISOLATED SHOWERS THAT ARE CURRENTLY POPPING UP AS WELL AS ANY FUTURE SHOWERS/TS THAT MAY INCUR LATER IN THE AFTERNOON DESPITE THE CAPPING IN PLACE. ALSO...WITH VERY LITTLE SHEAR TO WORK WITH...EXPECT WHAT DOES DEVELOP TO BE PULSY IN NATURE AND FAIRLY SHORT LIVED. OTHERWISE...ONGOING FORECAST SEEMS TO BE QUITE REASONABLE...SO DO NOT EXPECT ANY CRUCIAL UPDATES /OUTSIDE OF SHOWER DEVELOPMENT/ UNTIL AFTERNOON FORECAST PACKAGE. UPDATE ISSUED AT 751 AM EDT SAT JUN 8 2013 NO MAJOR CHANGES TO THE FORECAST. GFS 06Z MODEL GUIDANCE CAME IN WITH SLIGHTLY HIGHER WITH POPS FOR TODAY...20 PERCENT. RADAR MOSAIC STILL SHOWING AN OCCASIONAL POP UP FURTHER TO OUR WEST. THOUGHTS ARE THAT DIURNAL HEATING WILL ONLY HELP ADDITIONAL SHOWERS...THUNDERSTORMS TO FIRE LATER TODAY. SHORT WAVE RIDGING WILL BEGIN TO BUILD IN OVER THE AREA TODAY...WHILE UPPER LEVEL TROUGH LIFTS TO THE NORTHEAST. TODAYS FORECAST CHALLENGE WILL BE HOW STRONG WILL THE RESULTING DEVELOPING CAP BE AND HOW SOON WILL IT BEGIN TO DAMPEN CONVECTION GENERATED BY RELATIVELY WEAK SHORTWAVE ENERGY PASSING THROUGH THE AREA. IN GENERAL FORECAST SOUNDINGS SHOW THE CAP AT OR ABOVE 10 KFT THROUGH 18Z TO 21Z. 06Z NAM/10Z RAP FORECAST SOUNDINGS SUGGEST THE CAP WILL NOT BE STRONG ENOUGH TO PREVENT CONVECTION...BUT POSSIBLY SLOW GROWTH OF CELLS. ALSO...NAM/RAP SOUNDINGS DO NOT INHIBIT GROWTH ENOUGH TO PREVENT THE POTENTIAL OF THUNDER. ON THE OTHER HAND THE GFS ADVERTISES A STRONGER CAP...NOT STRONG ENOUGH TO PREVENT SHOWERS FROM FIRING...BUT ENOUGH TO KEEP THUNDER OUT OF THE FORECAST. HENSE THE LOWER POP GUIDANCE FROM THE GFS...SLIGHT VERSUS CHANCE FROM THE NAM GUIDANCE. THE HRRR SUGGEST AN UPTICK IN CONVECTION AFTER ABOUT 15Z OR 16Z...BEING MORE NUMEROUS OR SCATTERED IN NATURE. BUT THE HRRR USUALLY HAS A DIFFICULT TIME WITH CONVECTIVE INITIATION. DECIDED TO MAINTAIN OUR ORIGINAL SLIGHT POP...ISOLD COVERAGE THROUGH THE DAY AND ALSO KEPT A MENTION OF THUNDER BASED ON THE CONSENSUS OF THE NAM AND RAP SOUNDINGS. UPDATED GRIDS TO REFLECT MOST RECENT HOURLY OBS. NO CHANGES TO THE ZONE PACKAGE ATTM...THOUGH MOSTLY CLOUDY MIGHT BE A BETTER DESCRIPTION TO SKY COVER THAN THE CURRENT PC WORDING...AT LEAST THROUGH THE FIRST HALF OF THE DAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 359 AM EDT SAT JUN 8 2013 LIGHT RAIN SHOWERS OVER THE FAR SOUTHEAST WILL CONTINUE TO PUSH OFF TO THE EAST EARLY THIS MORNING...MOVING COMPLETELY OUT OF THE AREA WELL BEFORE SUNRISE. OTHERWISE...BAND OF BKN MID LEVEL CIGS ALONG WITH ISOLD SHOWERS...OR PATCHY SPRINKLES WILL CONTINUE TO PROGRESS SLOWLY EASTWARD ACROSS THE COMMONWEALTH FROM THE WEST THIS MORNING. UPPER LEVEL DISTURBANCE RESPONSIBLE FOR THIS ACTIVITY MAY GENERATE MORE WIDESPREAD CONVECTION LATER TODAY...ESPECIALLY IF FAVORABLE DIURNAL HEATING CAN BE TAPPED INTO. HOWEVER SHORTWAVE RIDGING WILL BEGIN BUILDING OVER THE REGION LATE THIS AFTERNOON...EFFECTIVELY STRENGTHENING A MID LEVEL CAP AND SHUTTING DOWN CONVECTION FAIRLY QUICKLY BY LATE AFTERNOON. FOCUS THEN MOVES TO OUR NEXT WEATHER MAKER...LOW PRESSURE SYSTEM MOVING OUT OF THE PLAINS AND INTO THE OHIO VALLEY BY LATE SUNDAY NIGHT INTO MONDAY. THIS NEXT SYSTEM WILL PROVIDE A MUCH BETTER CHANCE AT SOME RAINFALL. INCREASE POPS FOR TODAY AND SUNDAY AS WELL...FOLLOWING TRENDS IN MODELS AND MODEL GUIDANCE. FOR TEMPS JUST MADE SOME MINOR TWEAKS TOWARDS LATEST MODEL BLENDS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM EDT SAT JUN 8 2013 FORECAST MODELS ARE IN GOOD AGREEMENT ON THE TRACK OF AN UPPER LOW ACROSS THE OHIO VALLEY SUNDAY NIGHT THROUGH MONDAY NIGHT. THE UPPER LOW WILL SPONSOR A COLD FRONT WHICH WILL PASS THROUGH OUR REGION ON MONDAY. THIS SYSTEM WILL SCOOP UP SOME HIGH PWAT AIR AND SHOVE IT ACROSS EASTERN KENTUCKY FROM LATE SUNDAY NIGHT INTO MONDAY MORNING. THIS IS NOT THE MOST FAVORABLE TIME FRAME FOR CONVECTION SO WILL NOT GO HOG WILD WITH RAIN CHANCES JUST YET...KEEPING THEM BELOW CATEGORICAL RANGES. THE GFS BRINGS ANOTHER GOOD SHOT OF FORCING THROUGH DURING THE AFTERNOON AND EVENING...WHILE THE ECMWF/GEM/UKMET ALL HOLD THAT OFF UNTIL MONDAY NIGHT AS THE UPPER TROUGH SWINGS THROUGH. THE GFS SCENARIO COULD RESULT IN THE DEVELOPMENT OF STRONG THUNDERSTORMS MONDAY AFTERNOON...BUT WOULD TEND TO BELIEVE THAT THERE WILL BE TOO MUCH CLOUD COVER AND THEREFORE NOT ENOUGH INSTABILITY FOR STRONG CONVECTION. WILL HAVE TO WATCH THAT HOWEVER. OTHERWISE...RAIN CHANCES DECREASE MONDAY NIGHT INTO TUESDAY AS THE UPPER LOW WEAKENS AND PUSHES TO OUR NORTHEAST. SHORTWAVE RIDGING WILL BUILD INTO THE BLUEGRASS STATE TUESDAY THROUGH WEDNESDAY BEFORE ANOTHER SHORTWAVE IS PROGGED TO DIG SOUTHEAST INTO THE REGION ON THURSDAY. ANY SHOWER/TSTORM ACTIVITY WILL BE FEW AND FAR BETWEEN ON TUESDAY AND WEDNESDAY...AND TEMPERATURES WILL MODERATE WELL INTO THE 80S BY WEDNESDAY. SCATTERED SHOWERS/STORMS WILL THEN AGAIN BE ADVERTISED WEDNESDAY NIGHT THROUGH THURSDAY AND THIS WILL KNOCK BACK TEMPS A FEW DEGREES. A STOUT UPPER RIDGE IS THEN PROGGED TO BUILD NORTHEAST TOWARD THE REGION ON FRIDAY...RESULTING IN DWINDLING RAIN CHANCES ONCE AGAIN AS WE HEAD INTO NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 224 PM EDT SAT JUN 8 2013 MAIN FORECAST CONCERN WILL BE THE FOG THAT DEVELOPS IN MUCH OF THE VALLEY REGIONS OVERNIGHT. BEFORE THAT POINT...ISOLATED SHOWERS CURRENTLY ON RADAR HAVE THE POSSIBILITY TO AFFECT TAF SITES OVER THE NEXT FEW HOURS...THOUGH LITTLE IN THE WAY OF IMPACTS IS EXPECTED. SMALL SHORTWAVE ENERGY THAT IS PRODUCING THESE SHOWERS WILL CONTINUE TO LIFT OFF NORTHEAST...WITH EXPECTED CLEARING AS DAYTIME HEATING SUBSIDES THIS EVENING. FOG WILL THEN SET IN DURING THE OVERNIGHT...WITH GUIDANCE SHOWING THE MOST IMPACTS AT KSME WHERE IFR CONDITIONS ARE POSSIBLE. LEANED A LITTLE BIT MORE OPTIMISTICALLY FOR KJKL AND KLOZ...THOUGH SOME MVFR VIS MAY NOT BE OUT OF THE QUESTION. AS WE HEAD INTO TOMORROW...FOG WILL LIFT IN THE MORNING...BUT NEXT SHORTWAVE IS POISED TO IMPACT MUCH OF THE REGION BY EARLY AFTERNOON. EXACT TIMING AND LOCATION OF SHOWER DEVELOPMENT IS UNCERTAIN AT THIS TIME. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JMW SHORT TERM...RAY LONG TERM...ABE AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
751 AM EDT SAT JUN 8 2013 .UPDATE... ISSUED AT 751 AM EDT SAT JUN 8 2013 NO MAJOR CHANGES TO THE FORECAST. GFS 06Z MODEL GUIDANCE CAME IN WITH SLIGHTLY HIGHER WITH POPS FOR TODAY...20 PERCENT. RADAR MOSAIC STILL SHOWING AN OCCASIONAL POP UP FURTHER TO OUR WEST. THOUGHTS ARE THAT DIURNAL HEATING WILL ONLY HELP ADDITIONAL SHOWERS...THUNDERSTORMS TO FIRE LATER TODAY. SHORT WAVE RIDGING WILL BEGIN TO BUILD IN OVER THE AREA TODAY...WHILE UPPER LEVEL TROUGH LIFTS TO THE NORTHEAST. TODAYS FORECAST CHALLENGE WILL BE HOW STRONG WILL THE RESULTING DEVELOPING CAP BE AND HOW SOON WILL IT BEGIN TO DAMPEN CONVECTION GENERATED BY RELATIVELY WEAK SHORTWAVE ENERGY PASSING THROUGH THE AREA. IN GENERAL FORECAST SOUNDINGS SHOW THE CAP AT OR ABOVE 10 KFT THROUGH 18Z TO 21Z. 06Z NAM/10Z RAP FORECAST SOUNDINGS SUGGEST THE CAP WILL NOT BE STRONG ENOUGH TO PREVENT CONVECTION...BUT POSSIBLY SLOW GROWTH OF CELLS. ALSO...NAM/RAP SOUNDINGS DO NOT INHIBIT GROWTH ENOUGH TO PREVENT THE POTENTIAL OF THUNDER. ON THE OTHER HAND THE GFS ADVERTISES A STRONGER CAP...NOT STRONG ENOUGH TO PREVENT SHOWERS FROM FIRING...BUT ENOUGH TO KEEP THUNDER OUT OF THE FORECAST. HENSE THE LOWER POP GUIDANCE FROM THE GFS...SLIGHT VERSUS CHANCE FROM THE NAM GUIDANCE. THE HRRR SUGGEST AN UPTICK IN CONVECTION AFTER ABOUT 15Z OR 16Z...BEING MORE NUMEROUS OR SCATTERED IN NATURE. BUT THE HRRR USUALLY HAS A DIFFICULT TIME WITH CONVECTIVE INITIATION. DECIDED TO MAINTAIN OUR ORIGINAL SLIGHT POP...ISOLD COVERAGE THROUGH THE DAY AND ALSO KEPT A MENTION OF THUNDER BASED ON THE CONSENSUS OF THE NAM AND RAP SOUNDINGS. UPDATED GRIDS TO REFLECT MOST RECENT HOURLY OBS. NO CHANGES TO THE ZONE PACKAGE ATTM...THOUGH MOSTLY CLOUDY MIGHT BE A BETTER DESCRIPTION TO SKY COVER THAN THE CURRENT PC WORDING...AT LEAST THROUGH THE FIRST HALF OF THE DAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 359 AM EDT SAT JUN 8 2013 LIGHT RAIN SHOWERS OVER THE FAR SOUTHEAST WILL CONTINUE TO PUSH OFF TO THE EAST EARLY THIS MORNING...MOVING COMPLETELY OUT OF THE AREA WELL BEFORE SUNRISE. OTHERWISE...BAND OF BKN MID LEVEL CIGS ALONG WITH ISOLD SHOWERS...OR PATCHY SPRINKLES WILL CONTINUE TO PROGRESS SLOWLY EASTWARD ACROSS THE COMMONWEALTH FROM THE WEST THIS MORNING. UPPER LEVEL DISTURBANCE RESPONSIBLE FOR THIS ACTIVITY MAY GENERATE MORE WIDESPREAD CONVECTION LATER TODAY...ESPECIALLY IF FAVORABLE DIURNAL HEATING CAN BE TAPPED INTO. HOWEVER SHORTWAVE RIDGING WILL BEGIN BUILDING OVER THE REGION LATE THIS AFTERNOON...EFFECTIVELY STRENGTHENING A MID LEVEL CAP AND SHUTTING DOWN CONVECTION FAIRLY QUICKLY BY LATE AFTERNOON. FOCUS THEN MOVES TO OUR NEXT WEATHER MAKER...LOW PRESSURE SYSTEM MOVING OUT OF THE PLAINS AND INTO THE OHIO VALLEY BY LATE SUNDAY NIGHT INTO MONDAY. THIS NEXT SYSTEM WILL PROVIDE A MUCH BETTER CHANCE AT SOME RAINFALL. INCREASE POPS FOR TODAY AND SUNDAY AS WELL...FOLLOWING TRENDS IN MODELS AND MODEL GUIDANCE. FOR TEMPS JUST MADE SOME MINOR TWEAKS TOWARDS LATEST MODEL BLENDS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM EDT SAT JUN 8 2013 FORECAST MODELS ARE IN GOOD AGREEMENT ON THE TRACK OF AN UPPER LOW ACROSS THE OHIO VALLEY SUNDAY NIGHT THROUGH MONDAY NIGHT. THE UPPER LOW WILL SPONSOR A COLD FRONT WHICH WILL PASS THROUGH OUR REGION ON MONDAY. THIS SYSTEM WILL SCOOP UP SOME HIGH PWAT AIR AND SHOVE IT ACROSS EASTERN KENTUCKY FROM LATE SUNDAY NIGHT INTO MONDAY MORNING. THIS IS NOT THE MOST FAVORABLE TIME FRAME FOR CONVECTION SO WILL NOT GO HOG WILD WITH RAIN CHANCES JUST YET...KEEPING THEM BELOW CATEGORICAL RANGES. THE GFS BRINGS ANOTHER GOOD SHOT OF FORCING THROUGH DURING THE AFTERNOON AND EVENING...WHILE THE ECMWF/GEM/UKMET ALL HOLD THAT OFF UNTIL MONDAY NIGHT AS THE UPPER TROUGH SWINGS THROUGH. THE GFS SCENARIO COULD RESULT IN THE DEVELOPMENT OF STRONG THUNDERSTORMS MONDAY AFTERNOON...BUT WOULD TEND TO BELIEVE THAT THERE WILL BE TOO MUCH CLOUD COVER AND THEREFORE NOT ENOUGH INSTABILITY FOR STRONG CONVECTION. WILL HAVE TO WATCH THAT HOWEVER. OTHERWISE...RAIN CHANCES DECREASE MONDAY NIGHT INTO TUESDAY AS THE UPPER LOW WEAKENS AND PUSHES TO OUR NORTHEAST. SHORTWAVE RIDGING WILL BUILD INTO THE BLUEGRASS STATE TUESDAY THROUGH WEDNESDAY BEFORE ANOTHER SHORTWAVE IS PROGGED TO DIG SOUTHEAST INTO THE REGION ON THURSDAY. ANY SHOWER/TSTORM ACTIVITY WILL BE FEW AND FAR BETWEEN ON TUESDAY AND WEDNESDAY...AND TEMPERATURES WILL MODERATE WELL INTO THE 80S BY WEDNESDAY. SCATTERED SHOWERS/STORMS WILL THEN AGAIN BE ADVERTISED WEDNESDAY NIGHT THROUGH THURSDAY AND THIS WILL KNOCK BACK TEMPS A FEW DEGREES. A STOUT UPPER RIDGE IS THEN PROGGED TO BUILD NORTHEAST TOWARD THE REGION ON FRIDAY...RESULTING IN DWINDLING RAIN CHANCES ONCE AGAIN AS WE HEAD INTO NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 751 AM EDT SAT JUN 8 2013 DUE TO SOME LIGHT FOG VSBYS MAY START OUT WITHIN MVFR LEVELS DURING THE FIRST HOUR OF THE TAF BUT EXPECTING A QUICK REBOUND INTO VFR TERRITORY...AND FOR VFR CONDITIONS THROUGHOUT THE REMAINDER OF THE FORECAST PERIOD. MODEL GUIDANCE HAS TRENDED SLIGHTLY HIGHER WITH THE POTENTIAL OF RAIN...THOUGH FROM ALL APPEARANCES OUR SOUTHWEST TERMINAL MAY MISS OUT ON MOST OF THE ACTION. RADAR MOSAIC STILL SHOWING AN OCCASIONAL POP UP FURTHER TO OUR WEST. THOUGHTS ARE THAT DIURNAL HEATING WILL ONLY HELP ADDITIONAL SHOWERS...THUNDERSTORMS TO FIRE LATER TODAY AS A WEAK UPPER LEVEL DISTURBANCE PASSES THROUGH THE AREA. AT THIS TIME CONFIDENCE IS LOW WITH RESPECT TO THE EXACT AMOUNT OF COVERAGE OF CONVECTION ACROSS THE AREA...AND WHETHER TERMINALS WILL SEE ANYTHING WITHIN THE VICINITY OF EACH TERMINAL. BUT ADDED VCSH TO THE FORECAST TO COVER THE POTENTIAL. BASED ON LATEST FORECAST SOUNDINGS CAN NOT RULE OUT AN ISOLATED THUNDERSTORM EITHER...BUT THESE WOULD BE ISOLATED AT BEST. WINDS WILL BE LIGHT...INCREASING SLIGHTLY WHILE BECOMING MORE SOUTHWESTERLY THROUGH THE DAY SATURDAY. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...RAY LONG TERM...ABE AVIATION...RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
333 AM EDT SAT JUN 8 2013 .UPDATE... ISSUED AT 227 AM EDT SAT JUN 8 2013 JUST MINOR ADJUSTMENTS TO GRIDS FOR OUR EARLY MORNING UPDATE FOR NOW...TO INCORPORATE HOURLY TRENDS. BAND OF BKN MID LEVEL CIGS... ALONG WITH ISOLD SHOWERS...OR PATCHY SPRINKLES WILL PROGRESS SLOWLY EASTWARD ACROSS THE COMMONWEALTH THIS MORNING. UPPER LEVEL DISTURBANCE RESPONSIBLE FOR THIS ACTIVITY MAY GENERATE MORE WIDESPREAD CONVECTION SATURDAY PROPER IF IT CAN TAP INTO FAVORABLE DIURNAL HEATING. WILL BE LOOKING OVER LATEST RUNS IN MORE DETAIL TO DETERMINE OF AN INCREASE IN POPS MAY BE WARRANTED FOR SATURDAY. UPDATE ISSUED AT 1040 PM EDT FRI JUN 7 2013 UPDATED THE FIRST TWO PERIODS OF THE FORECAST. THE LATEST RADAR IMAGERY AND SURFACE OBSERVATIONS REVEALED THAT THERE SIMPLY DOES NOT APPEAR TO BE A GOOD TRIGGER TO SPAWN SHOWERS AND STORMS ACROSS EASTERN KENTUCKY THIS EVENING. SURFACE OBS HAVE BEEN SHOWING A FAIRLY LARGE TEMPERATURE DEW POINT GAP AS WELL...ESPECIALLY SOUTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80. SCATTERED SHOWERS AND STORMS HAVE BEEN FORMING FROM TIME TO TIME ACROSS NORTH CENTRAL TENNESSEE AND CENTRAL KENTUCKY...BUT THESE HAVE BE DISSIPATING RAPIDLY UPON ENTERING EASTERN KENTUCKY OR NOT MAKE IT IN HERE AT ALL. THAT BEING SAID...DECIDED TO LOWER POPS TO SLIGHT CHANCE ACROSS THE SOUTHERN AND EASTERN SECTIONS OF THE FORECAST AREA...AND GREATLY REDUCED THE WESTWARD EXTENT OF ANY SHOWERS OR STORMS THAT ARE ABLE TO HOLD TOGETHER IN EASTERN KENTUCKY TONIGHT AND TOMORROW. BASED ON CURRENT TRENDS...LACK OF FORCING AND LIMITED MOISTURE...ALSO DECIDED TO HAVE EASTERN KENTUCKY BE PRECIPITATION FREE BY 22 OR 23Z ON SATURDAY. LASTLY...REMOVED ANY REMAINING OUTDATED WORDING FROM THE ZONE FORECAST TEXT PRODUCT. THE REST OF THE FORECAST...TEMPERATURES...SKY...WINDS...WERE IN GOOD SHAPE WITH NO MAJOR CHANGES NEEDED. UPDATE ISSUED AT 730 PM EDT FRI JUN 7 2013 THE FORECAST HAS BEEN PRETTY MUCH ON TRACK SO FAR THIS EVENING...WITH NO UPDATE PLANNED AT THIS TIME. WILL UPDATE THE FORECAST LATER ON IN THE SHIFT TO REMOVE ANY OUTDATED WORDING AND TO REFRESH THE FORECAST GRIDS. IF ANY APPRECIABLE CHANGES OCCUR WITH THE SENSIBLE WEATHER...TEMPERATURES...SKY...AND PRECIPITATION COVERAGE IN PARTICULAR...WILL ISSUE ONE FINAL UPDATE BEFORE THE END OF THE SHIFT TO ACCOUNT FOR IT. AS IT STANDS...HAVE INGESTED THE LATEST ESTF DATA TO ESTABLISH NEW TRENDS...BUT NOTHING MORE. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 350 PM EDT FRI JUN 7 2013 19Z SFC ANALYSIS SHOWS TS ANDREA MOVING PAST THE REGION...WELL TO THE EAST AS IT MAKES ITS WAY UP THE EAST COAST. EARLIER...A FEW SHOWERS LINGERED OVER KENTUCKY/S WESTERN SLOPES OF THE APPALACHIANS... ALONG THE VIRGINA AND WEST VIRGINIA BORDER. THESE HAVE MOSTLY DISSIPATED WITH THE SOMEWHAT DRIER AIR...DEW POINTS DOWN NEAR 60...MOVING IN FROM THE NORTH. THE SKY ALSO STARTED TO BREAK UP DURING THE AFTERNOON IN CONJUNCTION WITH THE DRIER AIR ADVECTING INTO THE AREA IN THE WAKE OF ANDREA. THIS CLEARING LET TEMPERATURES SPIKE INTO THE MIDDLE AND UPPER 70S OVER THE PAST COUPLE OF HOURS THROUGHOUT MUCH OF EAST KENTUCKY. APPARENTLY...THIS IS STILL NOT ENOUGH TO POP ANY CONVECTION DEEPER INTO THE FORECAST AREA. HOWEVER...OVER WESTERN SECTIONS OF CENTRAL KENTUCKY...AN AREA OF SHOWERS AND THUNDERSTORMS ARE MAKING SLOW PROGRESS EAST. THIS AREA WILL NEED TO BE WATCHED FOR A POTENTIAL OF CONVECTION IN THESE PARTS BY EARLY EVENING. THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS THEY ALL TAKE THE SUPPORT FOR ANDREA OFF TO THE NORTHEAST WHILE TROUGHING MOVES THROUGH THE OHIO VALLEY. A MINOR WAVE DOES LIFT NORTHEAST FROM THE DEEP SOUTH...IN THE WAKE OF ANDREA...PASSING THROUGH EAST KENTUCKY THIS EVENING. ONCE THIS MOVES EAST ON SATURDAY...HEIGHTS WILL RISE THROUGHOUT THE REGION WITH SOME MODERATE RIDGING BUILDING IN FROM THE SOUTHEAST. THIS RIDGE WILL BE PUMPED IN RESPONSE TO DEEP TROUGHING DEVELOPING OVER THE HIGH PLAINS SATURDAY NIGHT. WITH THE CLOSE AGREEMENT OF THE MODELS...HAVE FOLLOWED A CONSENSUS FORECAST THROUGH SUNDAY MORNING...BUT KEYED IN ON THE NAM12 AND HRRR FOR NEAR TERM SPECIFICS. SENSIBLE WEATHER WILL FEATURE CLOUDS CLEARING FOR A BRIEF TIME LATE THIS AFTERNOON AND EARLY THIS EVENING BEFORE THE INFLUENCE OF THE UPPER WAVE TO THE SOUTH AND THE WAKE SUBSIDENCE OF ANDREA DEPARTS. THIS WILL BRING A RENEWED SMALL CHANCE OF SHOWERS OR THUNDERSTORMS TO MAINLY THE SOUTHERN PARTS OF EAST KENTUCKY THIS EVENING WITH A SMALL THREAT LINGERING IN THE FAR SOUTHEAST LATE TONIGHT INTO EARLY SATURDAY. THERE SHOULD BE ENOUGH CLEARING THROUGH THE NIGHT... THOUGH...ESPECIALLY AWAY FROM THE TENNESSEE AND VIRGINIA BORDERS... FOR WIDESPREAD FOG...LOCALLY DENSE...TO DEVELOP AFTER MIDNIGHT... CONTINUING INTO EARLY SATURDAY MORNING. WILL HIGHLIGHT THIS IN BOTH THE HWO AND THE ZFP. A WEAK SFC TROUGH TRAILING THE TROPICAL STORM WILL SLOWLY LIFT NORTH THROUGH EAST KENTUCKY DURING THE DAY SATURDAY AND THIS BOUNDARY MAY BE ENOUGH FOR SOME STRAY SHOWERS OR THUNDERSTORMS LATER IN THE DAY ON SATURDAY. WHAT EVER DEVELOPS WILL LIKELY DISSIPATE INTO THE NIGHT AND PATCHY VALLEY FOG WILL AGAIN BE A CONCERN. LOADED THE CONSSHORT WINDS AND DEW POINTS THROUGH THE FIRST 24 HOURS AND CONSALL FOR TD/WINDS AND MAX AND MIN TEMPERATURES THEREAFTER. DID NOT ADD MUCH TERRAIN DIFFERENCE TO THE LOWS DUE TO THE MOISTURE AND CLOUDS STILL AROUND TONIGHT AND SATURDAY NIGHT. AS FOR POPS...ENDED UP SIMILAR TO A BLEND OF THE WETTER MET AND DRIER MAV THROUGH THE SHORT TERM. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 333 AM EDT SAT JUN 8 2013 FORECAST MODELS ARE IN GOOD AGREEMENT ON THE TRACK OF AN UPPER LOW ACROSS THE OHIO VALLEY SUNDAY NIGHT THROUGH MONDAY NIGHT. THE UPPER LOW WILL SPONSOR A COLD FRONT WHICH WILL PASS THROUGH OUR REGION ON MONDAY. THIS SYSTEM WILL SCOOP UP SOME HIGH PWAT AIR AND SHOVE IT ACROSS EASTERN KENTUCKY FROM LATE SUNDAY NIGHT INTO MONDAY MORNING. THIS IS NOT THE MOST FAVORABLE TIME FRAME FOR CONVECTION SO WILL NOT GO HOG WILD WITH RAIN CHANCES JUST YET...KEEPING THEM BELOW CATEGORICAL RANGES. THE GFS BRINGS ANOTHER GOOD SHOT OF FORCING THROUGH DURING THE AFTERNOON AND EVENING...WHILE THE ECMWF/GEM/UKMET ALL HOLD THAT OFF UNTIL MONDAY NIGHT AS THE UPPER TROUGH SWINGS THROUGH. THE GFS SCENARIO COULD RESULT IN THE DEVELOPMENT OF STRONG THUNDERSTORMS MONDAY AFTERNOON...BUT WOULD TEND TO BELIEVE THAT THERE WILL BE TOO MUCH CLOUD COVER AND THEREFORE NOT ENOUGH INSTABILITY FOR STRONG CONVECTION. WILL HAVE TO WATCH THAT HOWEVER. OTHERWISE...RAIN CHANCES DECREASE MONDAY NIGHT INTO TUESDAY AS THE UPPER LOW WEAKENS AND PUSHES TO OUR NORTHEAST. SHORTWAVE RIDGING WILL BUILD INTO THE BLUEGRASS STATE TUESDAY THROUGH WEDNESDAY BEFORE ANOTHER SHORTWAVE IS PROGGED TO DIG SOUTHEAST INTO THE REGION ON THURSDAY. ANY SHOWER/TSTORM ACTIVITY WILL BE FEW AND FAR BETWEEN ON TUESDAY AND WEDNESDAY...AND TEMPERATURES WILL MODERATE WELL INTO THE 80S BY WEDNESDAY. SCATTERED SHOWERS/STORMS WILL THEN AGAIN BE ADVERTISED WEDNESDAY NIGHT THROUGH THURSDAY AND THIS WILL KNOCK BACK TEMPS A FEW DEGREES. A STOUT UPPER RIDGE IS THEN PROGGED TO BUILD NORTHEAST TOWARD THE REGION ON FRIDAY...RESULTING IN DWINDLING RAIN CHANCES ONCE AGAIN AS WE HEAD INTO NEXT WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 227 AM EDT SAT JUN 8 2013 EXPECTING VFR CONDITIONS THROUGHOUT THE FORECAST. MODEL GUIDANCE IS QUITE PESSIMISTIC WITH RESPECT TO VSBYS AND LIGHT FOG POTENTIAL. BUT UPPER LEVEL DISTURBANCE TRACKING THROUGH THE REGION THROUGH THE REMAINDER OF THE OVERNIGHT AND INTO SATURDAY IS RESPONSIBLE FOR A BAND OF BKN MID LEVEL CIGS ACROSS CENTRAL PORTIONS OF THE COMMONWEALTH. THIS BAND OF CLOUDS AND ASSOCIATED ISOLD SHOWER... PATCHY SPRINKLES SHOULD GRADUALLY SHIFT NORTHEASTWARD THROUGH THE REMAINDER OF THE FORECAST PERIOD. FEEL THESE CLOUDS WILL HELP KEEP ANY SIGNIFICANT FOG FROM DEVELOPING AND AS A RESULT HAVE GONE MORE OPTIMISTIC THAN WHAT GUIDANCE IS ADVERTISING. HOWEVER...FOG MAY BE MORE OF AN ISSUE FURTHER EAST ACROSS EXTREME EASTERN PORTIONS OF KY AS SKIES HAVE CONSIDERABLY LESS CLOUD COVER. WILL HAVE TO KEEP AN EYE ON VSBY AT KJKL AS MID LEVEL CIGS MAY NOT OVERSPREAD THERE UNTIL CLOSER TO DAWN. AFOREMENTIONED DISTURBANCE MAY KICK OFF SOME ISOLD SHOWER OR THUNDERSTORM ACTIVITY SATURDAY...BUT THE SYSTEM MAY HAVE PROGRESSED TOO FAR NORTHEASTWARD TO HAVE MUCH OF A CHANCE TO TAP INTO FAVORABLE DIURNAL HEATING TO GENERATE MORE WIDESPREAD ACTIVITY. THUS ONLY MENTIONED VCSH LATER IN THE DAY AT KJKL. AT THIS TIME CONFIDENCE IS LOW WITH RESPECT TO THE EXACT AMOUNT OF COVERAGE OF CONVECTION ACROSS THE AREA FOR SATURDAY PROPER. WINDS WILL BE LIGHT...INCREASING SLIGHTLY WHILE BECOMING MORE SOUTHWESTERLY THROUGH THE DAY SATURDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...RAY SHORT TERM...GREIF LONG TERM...ABE AVIATION...JP/RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
227 AM EDT SAT JUN 8 2013 .UPDATE... ISSUED AT 227 AM EDT SAT JUN 8 2013 JUST MINOR ADJUSTMENTS TO GRIDS FOR OUR EARLY MORNING UPDATE FOR NOW...TO INCORPORATE HOURLY TRENDS. BAND OF BKN MID LEVEL CIGS... ALONG WITH ISOLD SHOWERS...OR PATCHY SPRINKLES WILL PROGRESS SLOWLY EASTWARD ACROSS THE COMMONWEALTH THIS MORNING. UPPER LEVEL DISTURBANCE RESPONSIBLE FOR THIS ACTIVITY MAY GENERATE MORE WIDESPREAD CONVECTION SATURDAY PROPER IF IT CAN TAP INTO FAVORABLE DIURNAL HEATING. WILL BE LOOKING OVER LATEST RUNS IN MORE DETAIL TO DETERMINE OF AN INCREASE IN POPS MAY BE WARRANTED FOR SATURDAY. UPDATE ISSUED AT 1040 PM EDT FRI JUN 7 2013 UPDATED THE FIRST TWO PERIODS OF THE FORECAST. THE LATEST RADAR IMAGERY AND SURFACE OBSERVATIONS REVEALED THAT THERE SIMPLY DOES NOT APPEAR TO BE A GOOD TRIGGER TO SPAWN SHOWERS AND STORMS ACROSS EASTERN KENTUCKY THIS EVENING. SURFACE OBS HAVE BEEN SHOWING A FAIRLY LARGE TEMPERATURE DEW POINT GAP AS WELL...ESPECIALLY SOUTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80. SCATTERED SHOWERS AND STORMS HAVE BEEN FORMING FROM TIME TO TIME ACROSS NORTH CENTRAL TENNESSEE AND CENTRAL KENTUCKY...BUT THESE HAVE BE DISSIPATING RAPIDLY UPON ENTERING EASTERN KENTUCKY OR NOT MAKE IT IN HERE AT ALL. THAT BEING SAID...DECIDED TO LOWER POPS TO SLIGHT CHANCE ACROSS THE SOUTHERN AND EASTERN SECTIONS OF THE FORECAST AREA...AND GREATLY REDUCED THE WESTWARD EXTENT OF ANY SHOWERS OR STORMS THAT ARE ABLE TO HOLD TOGETHER IN EASTERN KENTUCKY TONIGHT AND TOMORROW. BASED ON CURRENT TRENDS...LACK OF FORCING AND LIMITED MOISTURE...ALSO DECIDED TO HAVE EASTERN KENTUCKY BE PRECIPITATION FREE BY 22 OR 23Z ON SATURDAY. LASTLY...REMOVED ANY REMAINING OUTDATED WORDING FROM THE ZONE FORECAST TEXT PRODUCT. THE REST OF THE FORECAST...TEMPERATURES...SKY...WINDS...WERE IN GOOD SHAPE WITH NO MAJOR CHANGES NEEDED. UPDATE ISSUED AT 730 PM EDT FRI JUN 7 2013 THE FORECAST HAS BEEN PRETTY MUCH ON TRACK SO FAR THIS EVENING...WITH NO UPDATE PLANNED AT THIS TIME. WILL UPDATE THE FORECAST LATER ON IN THE SHIFT TO REMOVE ANY OUTDATED WORDING AND TO REFRESH THE FORECAST GRIDS. IF ANY APPRECIABLE CHANGES OCCUR WITH THE SENSIBLE WEATHER...TEMPERATURES...SKY...AND PRECIPITATION COVERAGE IN PARTICULAR...WILL ISSUE ONE FINAL UPDATE BEFORE THE END OF THE SHIFT TO ACCOUNT FOR IT. AS IT STANDS...HAVE INGESTED THE LATEST ESTF DATA TO ESTABLISH NEW TRENDS...BUT NOTHING MORE. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 350 PM EDT FRI JUN 7 2013 19Z SFC ANALYSIS SHOWS TS ANDREA MOVING PAST THE REGION...WELL TO THE EAST AS IT MAKES ITS WAY UP THE EAST COAST. EARLIER...A FEW SHOWERS LINGERED OVER KENTUCKY/S WESTERN SLOPES OF THE APPALACHIANS... ALONG THE VIRGINA AND WEST VIRGINIA BORDER. THESE HAVE MOSTLY DISSIPATED WITH THE SOMEWHAT DRIER AIR...DEW POINTS DOWN NEAR 60...MOVING IN FROM THE NORTH. THE SKY ALSO STARTED TO BREAK UP DURING THE AFTERNOON IN CONJUNCTION WITH THE DRIER AIR ADVECTING INTO THE AREA IN THE WAKE OF ANDREA. THIS CLEARING LET TEMPERATURES SPIKE INTO THE MIDDLE AND UPPER 70S OVER THE PAST COUPLE OF HOURS THROUGHOUT MUCH OF EAST KENTUCKY. APPARENTLY...THIS IS STILL NOT ENOUGH TO POP ANY CONVECTION DEEPER INTO THE FORECAST AREA. HOWEVER...OVER WESTERN SECTIONS OF CENTRAL KENTUCKY...AN AREA OF SHOWERS AND THUNDERSTORMS ARE MAKING SLOW PROGRESS EAST. THIS AREA WILL NEED TO BE WATCHED FOR A POTENTIAL OF CONVECTION IN THESE PARTS BY EARLY EVENING. THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS THEY ALL TAKE THE SUPPORT FOR ANDREA OFF TO THE NORTHEAST WHILE TROUGHING MOVES THROUGH THE OHIO VALLEY. A MINOR WAVE DOES LIFT NORTHEAST FROM THE DEEP SOUTH...IN THE WAKE OF ANDREA...PASSING THROUGH EAST KENTUCKY THIS EVENING. ONCE THIS MOVES EAST ON SATURDAY...HEIGHTS WILL RISE THROUGHOUT THE REGION WITH SOME MODERATE RIDGING BUILDING IN FROM THE SOUTHEAST. THIS RIDGE WILL BE PUMPED IN RESPONSE TO DEEP TROUGHING DEVELOPING OVER THE HIGH PLAINS SATURDAY NIGHT. WITH THE CLOSE AGREEMENT OF THE MODELS...HAVE FOLLOWED A CONSENSUS FORECAST THROUGH SUNDAY MORNING...BUT KEYED IN ON THE NAM12 AND HRRR FOR NEAR TERM SPECIFICS. SENSIBLE WEATHER WILL FEATURE CLOUDS CLEARING FOR A BRIEF TIME LATE THIS AFTERNOON AND EARLY THIS EVENING BEFORE THE INFLUENCE OF THE UPPER WAVE TO THE SOUTH AND THE WAKE SUBSIDENCE OF ANDREA DEPARTS. THIS WILL BRING A RENEWED SMALL CHANCE OF SHOWERS OR THUNDERSTORMS TO MAINLY THE SOUTHERN PARTS OF EAST KENTUCKY THIS EVENING WITH A SMALL THREAT LINGERING IN THE FAR SOUTHEAST LATE TONIGHT INTO EARLY SATURDAY. THERE SHOULD BE ENOUGH CLEARING THROUGH THE NIGHT... THOUGH...ESPECIALLY AWAY FROM THE TENNESSEE AND VIRGINIA BORDERS... FOR WIDESPREAD FOG...LOCALLY DENSE...TO DEVELOP AFTER MIDNIGHT... CONTINUING INTO EARLY SATURDAY MORNING. WILL HIGHLIGHT THIS IN BOTH THE HWO AND THE ZFP. A WEAK SFC TROUGH TRAILING THE TROPICAL STORM WILL SLOWLY LIFT NORTH THROUGH EAST KENTUCKY DURING THE DAY SATURDAY AND THIS BOUNDARY MAY BE ENOUGH FOR SOME STRAY SHOWERS OR THUNDERSTORMS LATER IN THE DAY ON SATURDAY. WHAT EVER DEVELOPS WILL LIKELY DISSIPATE INTO THE NIGHT AND PATCHY VALLEY FOG WILL AGAIN BE A CONCERN. LOADED THE CONSSHORT WINDS AND DEW POINTS THROUGH THE FIRST 24 HOURS AND CONSALL FOR TD/WINDS AND MAX AND MIN TEMPERATURES THEREAFTER. DID NOT ADD MUCH TERRAIN DIFFERENCE TO THE LOWS DUE TO THE MOISTURE AND CLOUDS STILL AROUND TONIGHT AND SATURDAY NIGHT. AS FOR POPS...ENDED UP SIMILAR TO A BLEND OF THE WETTER MET AND DRIER MAV THROUGH THE SHORT TERM. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 355 PM EDT FRI JUN 7 2013 DURING THE SHORT TERM...EXPECT A 500MB TROUGH TO DEVELOP ACROSS SOUTHWESTERN CANADA AND BEGIN DROPPING SOUTHEASTWARD INTO THE PLAINS BY 12Z SUNDAY. MODELS ARE IN GOOD AGREEMENT OF SHOWING CONFINED AREA OF PRECIPITATION FORMING ALONG THE SURFACE COLD FRONT...MAKING ITS WAY INTO THE UPPER MISSISSIPPI VALLEY. KENTUCKY...ESPECIALLY EASTERN KY...WILL BE POSITIONED ON THE LEEWARD SIDE OF THE TROUGH...STARTING OFF THE MORNING DRY. HOWEVER...AS THE TROUGH CONTINUES TO NEAR DURING THE DAY...AND MOISTURE FLOW INCREASES OFF THE EASTERN COAST IN RELATION TO TROPICAL STORM ANDREA...PRECIP CHANCES WILL CONTINUE TO INCREASE THROUGHOUT THE DAY BOTH FROM THE EAST AND FROM THE WEST. ALTHOUGH EXTENDED MODELS ARE ALL IN GOOD AGREEMENT ABOUT THE PLACEMENT OF THE TROUGH...THEY ARE NOT SO SETTLED ON HOW MUCH OF AN IMPACT THE MOISTURE TO THE EAST WILL HAVE DURING THE DAY. FORECAST SOUNDINGS SHOW THE JACKSON AREA BEGINNING TO MOISTEN UP BY SUNDAY EVENING ACCORDING THE THE NAM AND SLIGHTLY LATER FOR THE GFS. FORECAST SOUNDINGS SHOW A PRETTY CAPPED ATMOSPHERE LEADING UP TO THIS...THOUGH WITH ANY HEATING OR LIFT...WOULD NOT BE UNLIKELY TO SEE A SOME ISOLATED TS DEVELOPMENT AS WELL. TROUGH WILL CONTINUE TO SINK SOUTHEAST INTO THE OHIO VALLEY WITH MAIN LINE OF PRECIP MOVING INTO THE REGION BY SUNDAY NIGHT...PICKING UP IN COVERAGE AS MOISTURE GETS PULLED IN FROM THE GULF AND FROM THE ATLANTIC. MONDAY LOOKS TO BE A WASH OUT THROUGH MUCH OF THE DAY AS A RESULT. WENT AHEAD AND RAISED POPS MARGINALLY COMPARED TO PREVIOUS FORECASTS BASED ON LATEST MODEL RUNS/CONSENSUS. AS THE TROUGH BEGINS TO PULL OUT TUESDAY AND STRONG RIDGING PATTERN ALLOWS DRIER AIR TO MOVE IN...MODELS START TO DIVERGE IN SOLUTIONS...THOUGH STILL FAIRLY GOOD AGREEMENT ON THE PRECIP ENDING ACROSS THE REGION...WITH THE GEM DRYING OUT SLIGHTLY FASTER. FOR WEDNESDAY THROUGH FRIDAY...MODELS CONTINUE TO DIVERGE ON SOLUTIONS AS A SERIES OF SHORTWAVES MOVE DOWN THE ACROSS THE MISSISSIPPI VALLEY. THIS WILL MEAN SEVERAL POTENTIAL RAIN MAKERS THROUGHOUT THE EXTENDED PERIOD...THOUGH MODEL SOLUTIONS ON EXACT TIMING AND LOCATION ARE LACKING. MODEL CONSENSUS CONTINUES TO SHOW BEST POTENTIALS THURSDAY AFTERNOON AND FRIDAY AFTERNOON IN CORRELATION WITH THE BEST HEATING/INSTABILITY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 227 AM EDT SAT JUN 8 2013 EXPECTING VFR CONDITIONS THROUGHOUT THE FORECAST. MODEL GUIDANCE IS QUITE PESSIMISTIC WITH RESPECT TO VSBYS AND LIGHT FOG POTENTIAL. BUT UPPER LEVEL DISTURBANCE TRACKING THROUGH THE REGION THROUGH THE REMAINDER OF THE OVERNIGHT AND INTO SATURDAY IS RESPONSIBLE FOR A BAND OF BKN MID LEVEL CIGS ACROSS CENTRAL PORTIONS OF THE COMMONWEALTH. THIS BAND OF CLOUDS AND ASSOCIATED ISOLD SHOWER... PATCHY SPRINKLES SHOULD GRADUALLY SHIFT NORTHEASTWARD THROUGH THE REMAINDER OF THE FORECAST PERIOD. FEEL THESE CLOUDS WILL HELP KEEP ANY SIGNIFICANT FOG FROM DEVELOPING AND AS A RESULT HAVE GONE MORE OPTIMISTIC THAN WHAT GUIDANCE IS ADVERTISING. HOWEVER...FOG MAY BE MORE OF AN ISSUE FURTHER EAST ACROSS EXTREME EASTERN PORTIONS OF KY AS SKIES HAVE CONSIDERABLY LESS CLOUD COVER. WILL HAVE TO KEEP AN EYE ON VSBY AT KJKL AS MID LEVEL CIGS MAY NOT OVERSPREAD THERE UNTIL CLOSER TO DAWN. AFOREMENTIONED DISTURBANCE MAY KICK OFF SOME ISOLD SHOWER OR THUNDERSTORM ACTIVITY SATURDAY...BUT THE SYSTEM MAY HAVE PROGRESSED TOO FAR NORTHEASTWARD TO HAVE MUCH OF A CHANCE TO TAP INTO FAVORABLE DIURNAL HEATING TO GENERATE MORE WIDESPREAD ACTIVITY. THUS ONLY MENTIONED VCSH LATER IN THE DAY AT KJKL. AT THIS TIME CONFIDENCE IS LOW WITH RESPECT TO THE EXACT AMOUNT OF COVERAGE OF CONVECTION ACROSS THE AREA FOR SATURDAY PROPER. WINDS WILL BE LIGHT...INCREASING SLIGHTLY WHILE BECOMING MORE SOUTHWESTERLY THROUGH THE DAY SATURDAY. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...GREIF LONG TERM...JMW/GEOGERIAN AVIATION...JP
AREA FORECAST DISCUSSION
NWS GRAY ME
936 AM EDT SAT JUN 8 2013 .SYNOPSIS... LOW PRESSURE ASSOCIATED WITH THE REMNANTS ANDREA NEAR CAPE COD THIS MORNING WILL RACE NORTHEAST INTO THE MARITIMES TODAY. A WEAK TROUGH OF LOW PRESSURE WILL LINGER IN ITS WAKE TONIGHT AND SUNDAY. HIGH PRESSURE WILL BUILD OVER THE REGION SUNDAY NIGHT AND WILL SHIFT OFFSHORE ON MONDAY AS A WARM FRONT APPROACHES FROM THE SOUTHWEST. THE WARM FRONT WILL STALL OVER SOUTHERN NEW ENGLAND MONDAY NIGHT AND TUESDAY AS LOW PRESSURE APPROACHES FROM THE WEST. LOW PRESSURE WILL SLOWLY CROSS THE REGION TUESDAY NIGHT AND WEDNESDAY AND WILL MOVE OUT TO SEA WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD OVER THE REGION ON THURSDAY AND FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... SHOWERS CONTINUE TO RACE EASTWARD TO THE CANADIAN MARITIMES IN ASSOC WITH THE REMAINS OF ANDREA. HAVE LOWERED POPS AND THE FLOOD WATCHES. LATEST HRRR HAS A GOOD HANDLE ON THE TIMING OF THE EXITING PCPN. AREA RIVERS WILL STILL BE ON THE RISE...BUT FLOODING IS NO LONGER EXPECTED. WILL INTRODUCE SOME SUNSHINE FOR THE REST OF TODAY AS A DRIER NW WIND ALLOWS FOR DOWNSLOPING. THIS SHOULD ALLOW SRN AREAS TO JUMP AOA 70 DEGREES FOR AN AFTN HIGH TEMP. PREV DISC... LOW PRESSURE OFF THE JERSEY COAST WILL CONTINUE TO RACE NORTHEAST THIS MORNING REACHING THE VICINITY OF CAPE COD BY 12Z. ALTHOUGH RAINFALL AMOUNTS NOT TOO IMPRESSIVE UP TO THIS POINT...EXPECT THE HEAVIEST OF THE RAINFALL TO OCCUR BETWEEN 06Z AND 15Z. LATEST RADAR SHOWING AN AREA OF HEAVY RAINFALL WITH SOME EMBEDDED THUNDERSTORMS PUSHING NORTHEAST THROUGH EASTERN MASS AND SOUTHERN NEW HAMPSHIRE AND THIS AREA WILL CONTINUE INTO SOUTHERN MAINE THROUGH DAYBREAK. STILL EXPECTING STORM TOTALS OF 2 TO 4 INCHES BY LATE THIS MORNING WHEN RAIN WILL BEGIN TAPERING OFF ACROSS THE FORECAST AREA. SEVERAL RIVERS FORECAST TO GO ABOVE FLOOD STAGE IN SOUTHERN NEW HAMPSHIRE AND MAINE LATER TODAY AND WILL BE CLOSELY MONITORED THROUGH THE MORNING HOURS. WITH NO FLOODING OCCURRING YET WILL CONTINUE FLOOD WATCHES FOR SOUTHERN NEW HAMPSHIRE AND MAINE. WILL SEE A WIDE RANGE IN HIGH TEMPS ACROSS THE FORECAST AREA TODAY AS SOME SUNNY BREAKS DEVELOP THIS AFTERNOON ACROSS SOUTHERN NEW HAMPSHIRE AND PERHAPS PORTIONS OF WESTERN MAINE BY LATE IN THE DAY. LOOKING FOR LOWER TO MID 70S IN THESE AREAS. FARTHER TO THE NORTH AND EAST TEMPS WILL TOP OUT IN THE UPPER 50S TO MID 60S. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... WEAK TROUGH OF LOW PRESSURE WILL LINGER IN THE WAKE OF THE DEPARTING LOW TONIGHT AND SUNDAY AS A WEAK SHORTWAVE PASSES THROUGH NORTHERN NEW ENGLAND. EXPECT CLOUDS TO HANG TOUGH OVER THE MOUNTAINS TONIGHT AND INTO SUNDAY AND THERE COULD BE A FEW SPRINKLES AT TIMES BUT SHOULDN`T BE ANYTHING TOO WIDESPREAD. REMAINDER OF THE REGION WILL SEE VARIABLE CLOUDS THROUGH SUNDAY. LOOKING FOR LOWS OVER NIGHT GENERALLY NEAR 50 IN MOST LOCATIONS. HIGHS ON SUNDAY WILL RANGE FROM THE MID 60S TO LOWER 70S IN THE NORTH AND RANGING THROUGH THE 70S IN THE SOUTH. && .LONG TERM /MONDAY THROUGH FRIDAY/... UPR LVL RIDGE SLOWLY BUILDING IN SUNDAY AND SUNDAY NGT WITH WEAK SFC HIGH AND DRY WX FOR THE FCST AREA. THE UPR LVL RIDGE BEGINS TO GET PUSHED TO THE E AS AN UPR LVL SHORT WAVE TROF MOVES E THRU THE MID WEST MONDAY AND MONDAY NGT. THIS FORCES A SFC LOW TO TRACK INTO THE GREAT LAKES WITH A WARM FNT EXTENDING TO THE SE TO THE E COAST. THIS WX SYSTEM WILL SPREAD SHRA NE INTO THE FCST AREA FROM SW TO NE MONDAY AFTERNOON AND NGT. THE UPR LVL SYSTEM CUTS OFF OVER THE NE INTO CLOSED LOW THAT FORCES THE SFC LOW TO BECOME NEARLY STATIONARY OVER THE REGION MONDAY NGT THRU WEDNESDAY NGT WITH SHRA CONTINUING. THE UPR LVL AND SFC LOWS FINALLY SHIFT TO THE E ON THURSDAY...BUT SLOW ENOUGH SO THAT SHRA MAY LINGER THRU THE DAY. GENERALLY LEANED MORE TOWARD THE ECMWF THOUGH IT IS SUPPORTED BY THE GFS UNTIL THURSDAY WHEN THE 00Z GFS DEPARTS FROM PREVIOUS RUNS AND THE ECMWF BY TRYING TO BRING IN A SECOND UPR LVL AND SFC SYSTEM TO EXTEND PRCP INTO FRIDAY. WITH THE PREFERRED ECMWF LOOKS LIKE FRIDAY SHOULD BE A DRY AND WARMER DAY. QPF AMOUNTS MONDAY AFTERNOON THRU THURSDAY COULD BE SIGNIFICANT WITH OVER AN INCH OF RAIN...OR MORE...PSBL. USED HPC QPF FOR PERIODS 4 AND 5 THEN BLEND OF GMOS AND GFS BEYOND THAT. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... SHORT TERM...IFR/LIFR CEILINGS THIS MORNING WILL GRADUALLY GIVE WAY TO VFR CONDITIONS FROM SOUTHWEST TO NORTHEAST THROUGH THE DAY. VFR TONIGHT AND SUNDAY. LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...LOWERING TO IFR OR LOWER IN DEVELOPING SHRA FROM SW TO NE MONDAY AFTERNOON AND EVENING THEN CONTINUING THRU WEDNESDAY. && .MARINE... SHORT TERM...CONTINUING SCA`S THROUGH TODAY. LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...WINDS AND GUSTS STAY BELOW SCA LEVELS. HOWEVER...EXTENDED PERIOD OF SE WINDS BACKING TO E THEN NE WILL GENERATE BUILDING SEAS THAT COULD REACH SCA LEVELS AROUND 5 OR 6 FT OVER THE OPEN WATERS FROM TUESDAY AFTERNOON THRU WEDNESDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ151- 153. SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ150-152-154. && $$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
358 AM EDT SAT JUN 8 2013 .SYNOPSIS... A WEAK DISTURBANCE WILL MOVE THROUGH THE SOUTHERN MID-ATLANTIC TODAY. A COLD FRONT WILL APPROACH ON MONDAY...MOVING ACROSS THE AREA LATE MONDAY NIGHT INTO TUESDAY. WEAK HIGH PRESSURE BUILDS IN WEDNESDAY...BEFORE ANOTHER COLD FRONT APPROACHES THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... WITH THE QUICK DEPARTURE OF THE REMNANTS OF ANDREA LATE LAST NIGHT...WE DRIED OUT FAIRLY QUICKLY BUT ANOTHER BATCH OF SHOWER ACTIVITY IS ON THE WAY. THE AIRMASS IS STILL QUITE MOIST EVEN W/ THE BRIEF NWLY FLOW REGIME...THAT IS NOW QUICKLY EXITING AS WELL. TYPICAL NW FLOW BRINGS SUBSIDENCE...BUT THIS NW FLOW WAS THE RESULT OF BEING ON THE BACKSIDE OF AN EXITING TROPICAL SYSTEM AS OPPOSED TO A SYNOPTIC-SCALE HIGH FROM THE GREAT LAKES. A DEEPENING IN-SITU TROUGH COMING IN BEHIND ANDREA ALSO HAS A WEAK EMBEDDED UPPER WAVE CAUGHT IN THE FLOW...NOW OVER THE CAROLINAS/SRN VA. THIS FEATURE WILL CONTINUE ON ITS WAY UP THE ERN SEABOARD THRU THE PREDAWN HRS AND INTO THE LATE MRNG. MOST GUIDANCE MEMBERS APPEAR TO NOT BE HANDLING THIS FEATURE WELL...FROM INITIALIZATION ONWARD. HRRR GUIDANCE IS ABOUT THE ONLY MEMBER TAKING THESE SEPARATE AREAS OF PRECIP AND TAKING THEM OVER PORTIONS OF THE CWA OVER THE NEXT SEVERAL HRS. TWO SEPARATE PRECIP AREAS DEFINE THIS UPPER WAVE...W/ AN AREA OF GOOD MTN CONVERGENCE CAUSING WIDESPREAD SHOWERS OVER THE SRN APLCNS AND ANOTHER BATCH OF SLIGHTLY HEAVIER AND MORE SCATTERED RAINFALL OVER CNTRL/ERN NC...HEADING UP THE I-95 CORRIDOR. THE HRRR HAS CONSISTENTLY TAKEN THE SRN APLCNS PRECIP AND SPREAD IT UP THE REMAINDER OF THE BLUE RIDGE AND INTO THE PIEDMONT OF OUR AREA BY MID-LATE MRNG. THE OTHER NC PRECIP BATCH WILL DRIFT TOWARD THE VA TIDEWATER AND UP TO LOWER SRN MD ABOUT THE SAME TIME. THOUGH THEY MAY HOLD TOGETHER FAIRLY WELL DURING THIS JOURNEY...STILL ONLY A FEW HUNDREDTHS OF AN INCH PRECIP EXPECTED W/ THEM AND A GRADUAL CLEARING BEHIND IT. LITTLE CHANGE OF AIRMASS INTO THE AFTN HRS WILL RESULT IN THE CHANCE FOR SOME ISOLATED SHOWERS ACROSS THE HIGHER TERRAIN LATER TODAY...MAINLY THE RESULT OF TERRAIN INTERACTION - SO LOWER PRECIP CHANCES E OF THE MTNS. HIGHS TOP OUT RIGHT AT THE CLIMO AVERAGES ACROSS THE CWA. SKIES SHOULD QUICKLY CLEAR OUT AFTER THE MRNG RAIN...W/ SOME MID CLOUD DECKS APPEARING ACROSS THE WRN HALF OF THE CWA THIS AFTN. OVERNIGHT LOWS WILL ONLY DROP INTO THE M-U60S...W/ DEWPOINTS HOLDING STEADY IN THE L60S...ANOTHER HUMID NIGHT. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... MODELS SHOW MOISTURE ALREADY RETURNING ON SUNDAY...WITH DEWPOINTS BACK IN THE 60S AND PRECIPITABLE WATER VALUES INCREASING TO AROUND 1.5 INCHES. THERE ARE SIGNS OF WARM ADVECTION OCCURRING TOO...AND THIS WILL RESULT IN INCREASED CLOUD COVER. DUE TO MOISTURE RETURN COULD SEE A FEW SHOWERS DURING THE MORNING HOURS. HOWEVER MAIN FOCUS FOR CHANCE POPS FOR SCATTERED CONVECTION WILL BE DURING THE AFTERNOON/EVENING ON SUNDAY DURING THE BEST INSTABILITY. GFS SUGGESTS 500-1000 J/KG CAPE IN THE AFTERNOON AND EVENING...NAM MORE LIKE 1000-1500 J/KG. && .LONG TERM /MONDAY THROUGH FRIDAY/... MOIST UNSTABLE AIR MASS REMAINS IN PLACE ON MONDAY IN A WARM SECTOR AHEAD OF LOW PRESSURE OVER THE LOWER GREAT LAKES. HEIGHT FALLS BEGIN ON MONDAY...AND CWA STARTS TO EXPERIENCE SOME UPPER DIVERGENCE AS WELL. AS SUCH...EXPECT MORE NUMEROUS CONVECTION ON MONDAY THAT MAY LINGER WELL INTO THE EVENING AHEAD OF A COLD FRONT. THERE IS SOME UNCERTAINTY WITH THE TIMING OF THE FRONT...WHICH WILL LIKELY PASS THROUGH LATE MONDAY NIGHT INTO TUESDAY. CONTINUE HIGH END CHANCE POPS THROUGH TUESDAY. FLAT RIDGE BUILDS IN FOR WEDNESDAY BUT GFS/ECMWF BOTH SHOW ANOTHER SHORTWAVE/FRONT TO AFFECT THE REGION ON THURSDAY WITH HIGH PRESSURE RETURNING BEHIND THIS SYSTEM. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... SOME FOG WILL DEVELOP ALONG SHELTERED VLYS AND A LOW CHANCE FOR SOME GROUND FOG ACROSS THE PIEDMONT AIRPORTS...MAINLY BECAUSE OF THE RECENT HEAVY RAINS AND IF AN AREA CAN GET CALM CONDITIONS FOR AN EXTENDED PERIOD OF TIME. WINDS BEHIND THE EXITING TROPICAL SYSTEM HAVE SWITCHED TO NWLY...WHICH WILL EVENTUALLY DROP OFF ACROSS THE AREA TO A LIGHT WLY AND EVENTUALLY SWLY WIND LATER THIS MRNG. SOME SCATTERED SHOWERS WILL SLIDE ACROSS THE AREA THRU NOON TODAY...THEN DRYING OUT AND CLEARING OUT IN LARGE PART THRU THE REST OF THE DAY/NIGHT. SCATTERED SHRA/TSRA ARE EXPECTED SUNDAY AFTERNOON/EVENING. THEN UNDER S/SE WINDS OPERATIONAL AND ENSEMBLE MODEL GUIDANCE FORECASTS LOW /IFR/ CIGS DEVELOPING SUNDAY NIGHT INTO EARLY MONDAY. CONFIDENCE IS LOW TO MEDIUM ON THIS ATTM. AS A FRONT APPROACHES MORE NUMEROUS CONVECTION MAY ALSO OCCUR ON MONDAY...PERHAPS LINGERING INTO TUESDAY UNTIL THE FRONTAL PASSAGE. && .MARINE... WINDS DYING DOWN QUICKLY ACROSS THE BAY. NOT LONG AGO...LOW END GALE GUSTS WERE OCCURRING OVER THE LOWER/MIDDLE BAY BUT NOW ONLY A FEW SCA GUSTS APPEARING. SCA WILL BE CANCELLED EARLY W/ THE QUICK WIND DISSIPATION AS ANDREA SPEEDS OFF THRU NEW ENGLAND AND AWAY FROM THE MID ATLC. WINDS WILL LARGELY BE LIGHT TODAY...W/ ONLY A BRIEF PERIOD OF STIFF SLY CHANNELING UP THE MAIN CHANNEL OF THE BAY LATER THIS EVE...BUT SCA CONDITIONS NOT EXPECTED FOR AT LEAST THE NEXT COUPLE OF DAYS. S/SE WINDS INCREASE ON SUNDAY...BUT LIKELY REMAIN BELOW SCA THRESHOLDS UNTIL PERHAPS MONDAY AFTERNOON/EVENING. COLD FRONT MOVES THROUGH ON TUESDAY...WITH A CHANCE OF SCA CONDITIONS BEHIND THE FRONT. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...GMS/BPP NEAR TERM...GMS SHORT TERM...BPP LONG TERM...BPP AVIATION...GMS/BPP MARINE...GMS/BPP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
751 PM EDT SUN JUN 9 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 412 PM EDT SUN JUN 9 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE OVER NW IA DOWNSTREAM OF A RIDGE OVER THE WRN CONUS. ANOTHER SHORTWAVE IS MOVING ACROSS ND AND ADJACENT SASKATCHEWAN/MANITOBA IN ASSOCIATION WITH A BROAD CLOSED MID LEVEL LOW OVER SW CANADA. SHORTWAVE OVER IA HAS MANAGED TO SWING A BAND OF SHRA N INTO WRN UPPER MI TODAY. SHRA HAVE BEEN SUPPORTED BY LOW/MID LEVEL FRONTOGENESIS AND PROBABLY SOME RIGHT ENTRANCE UPPER DIVERGENCE FROM JET STREAK EXTENDING FROM LAKE SUPERIOR TO NEW ENGLAND. ERN EDGE OF SHRA AREA HAS BATTLED ANTECEDENT DRY AIR MASS AT THE LOW/MID LEVELS PER 12Z KGRB/KAPX SOUNDINGS. IT APPEARS SPRINKLES HAVE REACHED AS FAR E AS MEMONINEE AND DICKINSON COUNTIES TODAY. WITH RECENT RADAR IMAGERY SHOWING ERN EDGE OF PCPN BAND FALLING APART AS IT MOVES FARTHER INTO DRIER AIR MASS...WILL SHOW A DIMINISHING POP TREND OVER THE W DURING THE NEXT SEVERAL HRS. SPRINKLES MAY GET AS FAR E AS WRN MARQUETTE COUNTY. OTHERWISE...WITH SHORTWAVE OVER IA DRIFTING ESE INTO IL TONIGHT...THIS DISTURBANCE IS NOT LIKELY TO PROVIDE ANY FORCING FOR PCPN OVER UPPER MI. IN FACT...PER QVECTORS...MODELS INDICATE A FAIRLY PRONOUNCED SPLIT IN DEEP LAYER FORCING DEVELOPING OVER UPPER MI BTWN THE WAVE MOVING INTO IL AND THE AFOREMENTIONED SHORTWAVE CURRENTLY OVER ND THAT WILL BE MOVING INTO FAR NE MN/NRN ONTARIO TONIGHT. THIS WILL LEAVE MUCH OF THE FCST AREA IN AN AREA OF LITTLE/NO DYNAMIC FORCING TONIGHT. SO...FCST TONIGHT WILL RETAIN THE IDEA OF HIGHER POPS OVER THE NW... ESPECIALLY TOWARD ISLE ROYALE...AND LOW CHC/SCHC POPS ELSEWHERE... EXCEPT FOR THE E WHICH SHOULD REMAIN DRY TONIGHT UNDER LINGERING MID/UPPER RIDGING. A NUMBER OF THE HIGHER RES MODELS SHOW REMNANTS OF CONVECTION DEVELOPING IN WRN LWR MI ROTATING NW INTO SCNTRL UPPER MI THIS EVENING. WILL BE INTERESTING TO SEE IF THAT DOES HAPPEN. SHORTWAVE THAT REACHES NE MN/ADJACENT NRN ONTARIO LATE TONIGHT WILL CONTINUE EASTWARD MON. WAVE WILL SUPPORT BETTER PCPN CHANCES ACROSS WRN AND NRN LAKE SUPERIOR INTO PORTIONS OF NW UPPER MI MON MORNING. MUCH OF THE FORCING WITH WAVE WILL THEN SHIFT N AND E OF THE AREA AS THE AFTN WEARS ON. ATTENTION THEN TURNS TO POTENTIAL FOR AFTN CONVECTION. NAM SHOWS MLCAPE INCREASING TO 150-500J/KG IN THE AFTN WITH THE GREATEST INSTABILITY OVER THE INTERIOR W HALF OF THE FCST AREA. THE GFS HAS SIMILAR VALUES...BUT ITS INSTABILITY IS CONFINED TO JUST THE W HALF OF UPPER MI. WITH THE POSSIBILITY OF THE TAIL END OF DEPARTING DEEP LAYER FORCING STILL SKIRTING THE AREA IN THE AFTN...AVBL INSTABILITY IS CERTAINLY SUFFICIENT FOR A MENTION OF SHRA OVER MUCH OF THE AREA IN THE AFTN (CHC POPS OVER THE INTERIOR W HALF AND SCHC E). CONVECTION OVER THE W SHOULD BE FURTHER AIDED BY LAKE BREEZE CONVERGENCE. OPTED TO INCLUDE SCHC THUNDER MENTION OVER THE INTERIOR W HALF WHERE INSTABILITY WILL BE MAXIMIZED. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 412 PM EDT SUN JUN 9 2013 DIURNALLY DRIVEN RAIN SHOWERS AND THUNDERSTORMS ACROSS THE INTERIOR WEST AND CENTRAL AREAS WILL DIMINISH MONDAY NIGHT AS WE LOSE HEATING OVERNIGHT. MEANWHILE...LOW PRESSURE WILL MOVE FROM SASKATCHEWAN INTO ONTARIO BY TUESDAY EVENING. THIS WILL BRING A SHORTWAVE ACROSS UPPER MICHIGAN TUESDAY. ADDITIONALLY...LOW PRESSURE WILL MOVE FROM THE OHIO VALLEY TOWARDS THE NEW ENGLAND STATES. HIGH PRESSURE CENTERED OVER TEXAS WILL KEEP A RIDGE ACROSS MUCH OF THE CENTRAL U.S. FOR THIS TIME PERIOD. AS IT IS...UPPER MICHIGAN WILL BE UNDER THE INFLUENCE OF WEAK RIDGING AND A PASSING SUBTLE SHORTWAVE TUESDAY. THOUGH THERE WILL BE MOISTURE LINGERING AROUND/PWATS UP TO 115 PERCENT OF NORMAL...PRECIPITATION WILL BE LIMITED BY THIS RIDGE OVER LAND. HAVE SLIGHT CHANCE POPS MOVING WEST TO EAST ACROSS THE CWA THROUGH THE DAY ON TUESDAY. THE BEST FORCING WITH THIS SHORTWAVE IS PRIMARILY NORTH OF LAKE SUPERIOR...SO CHANCE POPS ARE ACROSS THE WESTERN AND NORTHERN PORTIONS OF THE LAKE WITH THE SHORTWAVE. ADDITIONAL SHOWERS COULD POP UP ALONG THE LAKE BREEZE BOUNDARIES TOWARDS THE AFTERNOON...SO KEPT SLIGHT CHANCE POPS IN THIS AREA UNTIL 00Z. AS FOR WEDNESDAY...WITH HIGH PRESSURE SETTING UP ACROSS THE CENTRAL U.S. EXPECT MCS DEVELOPMENT TO OCCUR ALONG THE RIDGE BOUNDARY AS SEVERAL SHORTWAVES SLIDE THROUGH. THIS WILL REMAIN SOUTH OF UPPER MICHIGAN HOWEVER...LIKELY OVER CENTRAL/LOWER WI. THE UPPER LOW THAT BROUGHT THE SHORTWAVE THROUGH UPPER MI ON TUESDAY WILL CONTINUE TO GENERATE PRECIPITATION...OVER PRIMARILY ONTARIO AND QUEBEC. WITH RIDGE EXPANDING NORTHWARD DO NOT EXPECT ANYTHING MORE THAN SOME SCATTERED CLOUD COVER OVER UPPER MI. THE RIDGE OF HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES REGION FOR THURSDAY AND MUCH OF FRIDAY...WHICH WILL KEEP THE WEATHER QUIET. WITH COOL NORTHERLY WINDS OFF THE LAKE ON THURSDAY AND MIXING TO AROUND 950MB IN MOST LOCATIONS EXPECT HIGH TEMPERATURES TO RANGE FROM THE MID 60S TO LOW 70S...WITH THE WARMER TEMPERATURES INLAND FROM LAKE SUPERIOR. REGIONS CLOSEST TO THE LAKES COULD SEE SLIGHTLY LOWER TEMPERATURES. ON FRIDAY AFTERNOON CLOUD COVER IN THE WEST INCREASES WITH AN APPROACHING AREA OF LOW PRESSURE. STILL EXPECT MOST AREAS TO EXPERIENCE FULL DAYTIME HEATING THOUGH...AND WITH BETTER MIXING TO THE 850MB LEVEL/TEMPS AROUND 12-14C AND DEVELOPING SOUTHERLY WINDS EXPECT HIGHS TO REACH INTO THE MID 70S AWAY FROM LAKE SUPERIOR. FRIDAY NIGHT-SUNDAY LOW PRESSURE OVER MANITOBA WILL CROSS EASTWARD INTO QUEBEC...JUST NORTH OF LAKE SUPERIOR. CORRESPONDING COLD FRONT WILL CROSS UPPER MICHIGAN SATURDAY AFTERNOON INTO SUNDAY EVENING. WITH SOUTHERLY WINDS BRINGING MORE MOISTURE TO THE AREA/DEWPOINTS NEARING 60F/ AND PASSAGE OF THE COLD FRONT...EXPECT SHOWERS AND A FEW THUNDERSTORMS TO SPREAD EASTWARD ACROSS THE CWA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 729 PM EDT SUN JUN 9 2013 ISOLD SHRA WILL CONTINUE TO AFFECT KCMX AND PERHAPS KIWD INTO THE EARLY EVENING BEFORE DISSIPATING. E TO SE PREVAILING FLOW SHOULD HELP MAINTAIN SOMEWHAT DRIER AIR AT THE LOW-LEVELS...KEEPING CONDITIONS VFR DESPITE PCPN. WITH RAINFALL WETTING THE GROUND MORE SO AT KIWD...THERE IS THE POTENTIAL FOR LOWER CLOUDS/FOG TO FORM TONIGHT. HOWEVER...SINCE LOW-LEVEL WINDS REMAIN FROM A DOWNSLOPING SE DIRECTION...POTENTIAL APPEARS MINIMAL. EARLY MON AFTN...DAYTIME HEATING MAY BEGIN TO POP A FEW SHRA...ESPECIALLY AROUND KIWD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 PM EDT SUN JUN 9 2013 AS LOW PRES OVER NW IA DRIFTS E...EXPECT EASTERLY WINDS UP TO AROUND 20KT ACROSS LAKE SUPERIOR THRU MON. LOCALLY HIGHER WINDS TO AROUND 25KT SHOULD OCCUR OVER THE FAR W THRU THIS EVENING DUE TO COASTAL CONVERGENCE. WITH SOME RAIN FALLING OVER THE WRN PART OF THE LAKE... PATCHY FOG MAY DEVELOP TONIGHT OVER THE W. WEAK HIGH PRES WILL RETURN AND BRING GENERALLY LIGHT WINDS FOR TUE THRU FRI. MUCH OF THAT PERIOD WILL SEE WINDS AOB 15KT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...MCD AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
706 PM EDT SAT JUN 8 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 406 PM EDT SAT JUN 8 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE MOVING ACROSS NRN LAKE MI INTO NRN LWR MI. AREA OF SHRA ASSOCIATED WITH SHORTWAVE HAS PASSED S OF UPPER MI TODAY. HOWEVER...DAYTIME HEATING HAS RESULTED IN JUST ENOUGH INSTABILITY FOR ISOLD SHRA TO DEVELOP ACROSS INTERIOR W AND CNTRL UPPER MI THIS AFTN (LATEST SPC MESOANALYSIS SHOWS SBCAPE OF 100-200J/KG). TO THE W...A SHORTWAVE TROF IS DIGGING INTO THE WRN PLAINS DOWNSTREAM OF A W COAST RIDGE. THIS TROF WILL BRING THE NEXT POSSIBILITY OF RAIN TO THE AREA SUN. TONIGHT...WITH LOSS OF DAYTIME HEATING...ISOLD SHRA OVER THE INTERIOR WILL DISSIPATE BY MID EVENING. OTHERWISE...FCST AREA TONIGHT WILL BE UNDER THE INFLUENCE OF SHORTWAVE RIDGE AXIS TO THE E OF THE SHORTWAVE DIGGING THRU THE PLAINS. WITH RIDGE PROVIDING SUBSIDENCE/QVECTOR DIVERGENCE...EXPECT A DRY NIGHT AND A TREND TO MCLEAR SKIES. LOWEST MIN TEMPS SHOULD BE OVER THE INTERIOR E AS PRES GRADIENT/SE GRADIENT FLOW IS FCST TO SHARPEN LATE OVER THE W...WHERE SOME HIGH CLOUDS SHOULD ALSO ARRIVE LATER IN THE NIGHT. GIVEN THE DEGREE TO WHICH JET STREAK IS CAUSING SHORTWAVE TO DIG INTO THE WRN PLAINS CURRENTLY...MAIN PIECE OF ENERGY AND ASSOCIATED PCPN WILL LIKELY END UP SW OF HERE SUN. THIS WILL ALLOW DRIER EASTERLY FLOW EMANATING FROM SFC HIGH PRES RIDGE ASSOCIATED WITH MID/UPPER LEVEL RIDGING FROM THE GREAT LAKES TO HUDSON BAY TO HAVE A MORE DOMINANT INFLUENCE IN THE WEATHER HERE. MODELS THAT WERE MORE AGGRESSIVE IN RECENT RUNS WITH PCPN DRIVING INTO UPPER MI SUN HAVE ALL BACKED OFF WITH EASTWARD EXTENT OF PCPN WHICH SUPPORTS THE ABOVE THINKING. WHILE ONE PIECE OF ENERGY WILL BE OVER IA SUN...ANOTHER SHORTWAVE WILL BE SWINGING FROM THE DAKOTAS TOWARD NE MN...SPREADING AN ARC OF WEAK DEEP LAYER QVECTOR CONVERGENCE INTO WRN UPPER MI. WITH ZONE OF MOISTURE TRANSPORT IN THAT AREA AS WELL...THIS WAVE MAY BE SUFFICIENT TO BRING PCPN INTO WRN UPPER MI SUN AFTN. SO... PLAN FOR THIS FCST ISSUANCE IS TO CUT BACK ON PCPN ADVANCEMENT INTO UPPER MI SUN. WILL KEEP ROUGHLY THE E HALF DRY THRU THE AFTN WITH HIGH CHC POPS OVER THE W TRENDING TO LIKELY FAR W TOWARD KIWD. WITH LESS AND LATER PCPN ARRIVAL...BUMPED TEMPS UP ACROSS THE BOARD. IN THE INTERIOR...TEMPS SHOULD REACH THE LOW/MID 70S SUN. THICKER CLOUDS SHOULD HOLD TEMPS TO THE MID/UPPER 60S FAR W. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 406 PM EDT SAT JUN 8 2013 A CONTINUED SLOW MOVING AND MESSY PATTERN WILL CONTINUE WELL INTO NEXT WEEK AS WEAK BLOCKING DOMINATES THE FLOW ACROSS THE CONUS AND CANADA. SUNDAY NIGHT AND MONDAY...IT SEEMS THE MODEL FORECASTS HAVE BEEN CHANGING A DECENT AMOUNT FROM DAY TO DAY...WITH THE LAST SUITE REALLY CUTTING BACK PRECIP CHANCES FOR THE EAST HALF. HAVE CONTINUED TO USE OF THE GFS AS THE ECMWF HAS COME MORE INTO LINE WITH IT OVER THE PAST SEVERAL RUNS. THE GENERAL PATTERN HAS A WEAK REX BLOCK...WITH A SHORTWAVE/NEARLY CLOSED LOW TACKING ACROSS THE UPPER MS VALLEY ON SUNDAY WHILE A WEAK RIDGE EXTENDS NORTHWARD THROUGH NORTHERN ONTARIO TO OVER HUDSON BAY. ENERGY WITH THE SHORTWAVE WILL SPLIT TO BECOME A NORTHEASTWARD MOVING TROUGH AND AN EASTWARD MOVING CLOSED LOW. THE LOW WILL TRACK TOO FAR SOUTH OF THE CWA TO PROVIDE ANY GOOD SUPPORT FOR WIDESPREAD RAINFALL. MEANWHILE...THE MAIN TROUGH WILL CLIP THE WESTERN CWA WITH DECENT H7 FGEN AND MID-LEVEL Q-VECTOR CONVERGENCE. THE EAST HALF LOOKS TO MISS OUT ONCE AGAIN ON THE WIDESPREAD RAIN. HAVE DROPPED PRECIP WORDING COMPLETELY FROM THE FAR EAST...AND CUT BACK THE POPS ACROSS THE REST OF THE CWA. ONLY CHANCE OF SEEING A VERY ISOLATED RUMBLE OF THUNDER WOULD BE NEAR MENOMINEE...SO REMOVED THE SLIGHT CHANCE OF THUNDER PREVIOUSLY ALONG THE WI BORDER. MONDAY AND MONDAY NIGHT...SOME SUPPORT FROM THE SHORTWAVE ALONG WITH AN INCOMING UPPER JET WILL RESULT IN SCATTERED SHOWERS ACROSS THE CWA THROUGHOUT THE DAY. AGAIN...THE BEST CHANCE REMAINS OVER THE NORTHWEST CWA. AFTER A WEAK AND ELONGATED UPPER PV ANOMALY AND ASSOCIATED MID-LEVEL Q-VECTOR CONVERGENCE PUSH EAST MONDAY EVENING...INCREASING SUBSIDENCE SHOULD ALLOW FOR CLEARING ALOFT FOR THE WEST. WITH NO SOURCE OF LOW-LEVEL DRY AIR...FAIRLY LIGHT WINDS...AND RECENT RAINFALL...EXPECT LOW CLOUDS TO REMAIN AND PATCHY FOG TO FORM OVERNIGHT. FOG FORMATION WILL BE HEAVILY DEPENDENT ON HOW QUICK THE MID-LEVEL CLOUDS DEPART...SO DO NOT WANT TO GET TOO DETAILED IN SPECIFIC AREAS. FOR NOW...ADDED WORDING OF PATCHY FOG ACROSS THE INTERIOR WESTERN THIRD OF THE CWA WHERE CLEARING LOOKS TO BE MORE LIKELY. ALSO...WINDS WILL CONTINUE TO BACK TO A MORE NW WIND DIRECTION FOR THE WEST HALF...AND EVENTUALLY THE EAST HALF. THIS SHOULD LEAD TO SOME UPSLOPE DRIZZLE FORMATION ACROSS THE WEST AND CENTRAL FOR LOCATIONS PRONE TO NW UPSLOPE FLOW. TUESDAY...WAS INITIALLY GOING TO KEEP PRECIP OUT OF THE FORECAST...BUT ON SECOND GLANCE...A 100KT UPPER JET STREAK DIVING SOUTHEAST OVER UPPER MI SHOULD GIVE SOME SUPPORT FROM BOTH THE LEFT EXIT AND RIGHT ENTRANCE REGIONS. EXPECTATION IS THAT THE EXTRA LIFT UNDER THE JET WILL TAP INTO THE LITTLE REMAINING LOW-LEVEL MOISTURE AT THE SFC TO PRODUCE SOME ISOLATED SHOWERS IN THE MORNING...THEN SOME MORE DIURNALLY ENHANCED SHOWERS INLAND FOR THE AFTERNOON. WEDNESDAY AND THURSDAY...A QUICK-MOVING MID-LEVEL SHORTWAVE TROUGH WILL ROUND THE NORTHERN EXTENT OF A BUILDING RIDGE IN THE CENTRAL PLAINS ON WEDNESDAY. THIS TROUGH WILL BE PICKED UP BY AN ELONGATED TROUGH STRETCHING SOUTHWEST FROM A BROAD MID-LEVEL LOW OVER SOUTHERN QUEBEC. WHILE A BOUT OF MID-LEVEL Q-VECTOR CONVERGENCE PASSES OVER UPPER MI ON WEDNESDAY...MOISTURE WILL BE LACKING THROUGHOUT MUCH OF THE LAYER. MODEL TRENDS HAVE BEEN PUSHING FORCING AND ASSOCIATED PRECIP FARTHER SOUTH OVER THE PAST COUPLE DAYS...SO ALL BUT SOME MID TO HIGH CLOUDS ALONG THE WI BORDER SHOULD STAY CLEAR OF THE CWA. ONCE AGAIN...ON THURSDAY AFTERNOON...A WEAK UPPER PV ANOMALY AND MID-LEVEL SHORTWAVE TRACKING SOUTHEAST ACROSS THE CWA WILL STRUGGLE TO GENERATE EVEN MID TO HIGH-LEVEL CLOUDS GIVEN A DEEP DRY LAYER. FRIDAY AND SATURDAY...THE BUILDING RIDGE TO THE WEST WILL PUSH INTO THE REGION AND BRING DRY CONDITIONS FOR FRIDAY. THEN A SHORTWAVE TROUGH EJECTING FROM A DEEP TROUGH OVER THE WEST COAST WILL TRY TO RIDE OVER THE TOP OF THE RIDGE FRIDAY NIGHT INTO SATURDAY. IT REMAINS TO BE SEEN HOW MUCH THIS TROUGH WILL BE ABLE TO ERODE THE TOP OF THE RIDGE. FOR NOW...ENOUGH INSTABILITY AND MOISTURE SHOULD EXIST TO GENERATE SOME THUNDERSTORM ACTIVITY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 655 PM EDT SAT JUN 8 2013 EXPECT VFR CONDITIONS AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD AS A DRY LOW-LEVEL AIR MASS REMAINS IN PLACE. WINDS WILL REMAIN LIGHT THRU THE PERIOD...GENERALLY BECOMING SOUTHEAST ON SUNDAY. EXPECT SOME INCREASE IN MID-LVL CLOUDS AGAIN SUNDAY AFTERNOON AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM THE NRN PLAINS. INCLUDED SOME VCSH AT KIWD AS THE FAR WRN CWA WILL BE ON THE EDGE OF THE BETTER FORCING AND DEEPER MOISTURE ASSOC WITH THIS FEATURE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 406 PM EDT SAT JUN 8 2013 WITH HIGH PRESSURE MOVING OVER LAKE SUPERIOR AND HIGH OVERWATER STABILITY...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. THEN...A LOW PRESSURE SYSTEM MOVING E TO THE MID MISSISSIPPI VALLEY SUN NIGHT WILL TIGHTEN THE PRESSURE GRADIENT...RESULTING IN EASTERLY WINDS INCREASING UP TO 20KT SUN INTO EARLY MON. COASTAL CONVERGENCE COULD RESULT IN LOCALIZED HIGHER WINDS UP TO 25KT OVER FAR WRN LAKE SUPERIOR BTWN THE APOSTLE ISLANDS AND MN N SHORE SUN AFTN/EVENING. AS THE LOW SHIFTS E...ANOTHER WEAK HIGH PRES SYSTEM WILL SETTLE INTO THE UPPER GREAT LAKES TUE THRU THU...RESULTING IN WINDS UNDER 15KT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KLUBER AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
407 PM EDT SAT JUN 8 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 406 PM EDT SAT JUN 8 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE MOVING ACROSS NRN LAKE MI INTO NRN LWR MI. AREA OF SHRA ASSOCIATED WITH SHORTWAVE HAS PASSED S OF UPPER MI TODAY. HOWEVER...DAYTIME HEATING HAS RESULTED IN JUST ENOUGH INSTABILITY FOR ISOLD SHRA TO DEVELOP ACROSS INTERIOR W AND CNTRL UPPER MI THIS AFTN (LATEST SPC MESOANALYSIS SHOWS SBCAPE OF 100-200J/KG). TO THE W...A SHORTWAVE TROF IS DIGGING INTO THE WRN PLAINS DOWNSTREAM OF A W COAST RIDGE. THIS TROF WILL BRING THE NEXT POSSIBILITY OF RAIN TO THE AREA SUN. TONIGHT...WITH LOSS OF DAYTIME HEATING...ISOLD SHRA OVER THE INTERIOR WILL DISSIPATE BY MID EVENING. OTHERWISE...FCST AREA TONIGHT WILL BE UNDER THE INFLUENCE OF SHORTWAVE RIDGE AXIS TO THE E OF THE SHORTWAVE DIGGING THRU THE PLAINS. WITH RIDGE PROVIDING SUBSIDENCE/QVECTOR DIVERGENCE...EXPECT A DRY NIGHT AND A TREND TO MCLEAR SKIES. LOWEST MIN TEMPS SHOULD BE OVER THE INTERIOR E AS PRES GRADIENT/SE GRADIENT FLOW IS FCST TO SHARPEN LATE OVER THE W...WHERE SOME HIGH CLOUDS SHOULD ALSO ARRIVE LATER IN THE NIGHT. GIVEN THE DEGREE TO WHICH JET STREAK IS CAUSING SHORTWAVE TO DIG INTO THE WRN PLAINS CURRENTLY...MAIN PIECE OF ENERGY AND ASSOCIATED PCPN WILL LIKELY END UP SW OF HERE SUN. THIS WILL ALLOW DRIER EASTERLY FLOW EMANATING FROM SFC HIGH PRES RIDGE ASSOCIATED WITH MID/UPPER LEVEL RIDGING FROM THE GREAT LAKES TO HUDSON BAY TO HAVE A MORE DOMINANT INFLUENCE IN THE WEATHER HERE. MODELS THAT WERE MORE AGGRESSIVE IN RECENT RUNS WITH PCPN DRIVING INTO UPPER MI SUN HAVE ALL BACKED OFF WITH EASTWARD EXTENT OF PCPN WHICH SUPPORTS THE ABOVE THINKING. WHILE ONE PIECE OF ENERGY WILL BE OVER IA SUN...ANOTHER SHORTWAVE WILL BE SWINGING FROM THE DAKOTAS TOWARD NE MN...SPREADING AN ARC OF WEAK DEEP LAYER QVECTOR CONVERGENCE INTO WRN UPPER MI. WITH ZONE OF MOISTURE TRANSPORT IN THAT AREA AS WELL...THIS WAVE MAY BE SUFFICIENT TO BRING PCPN INTO WRN UPPER MI SUN AFTN. SO... PLAN FOR THIS FCST ISSUANCE IS TO CUT BACK ON PCPN ADVANCEMENT INTO UPPER MI SUN. WILL KEEP ROUGHLY THE E HALF DRY THRU THE AFTN WITH HIGH CHC POPS OVER THE W TRENDING TO LIKELY FAR W TOWARD KIWD. WITH LESS AND LATER PCPN ARRIVAL...BUMPED TEMPS UP ACROSS THE BOARD. IN THE INTERIOR...TEMPS SHOULD REACH THE LOW/MID 70S SUN. THICKER CLOUDS SHOULD HOLD TEMPS TO THE MID/UPPER 60S FAR W. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 406 PM EDT SAT JUN 8 2013 A CONTINUED SLOW MOVING AND MESSY PATTERN WILL CONTINUE WELL INTO NEXT WEEK AS WEAK BLOCKING DOMINATES THE FLOW ACROSS THE CONUS AND CANADA. SUNDAY NIGHT AND MONDAY...IT SEEMS THE MODEL FORECASTS HAVE BEEN CHANGING A DECENT AMOUNT FROM DAY TO DAY...WITH THE LAST SUITE REALLY CUTTING BACK PRECIP CHANCES FOR THE EAST HALF. HAVE CONTINUED TO USE OF THE GFS AS THE ECMWF HAS COME MORE INTO LINE WITH IT OVER THE PAST SEVERAL RUNS. THE GENERAL PATTERN HAS A WEAK REX BLOCK...WITH A SHORTWAVE/NEARLY CLOSED LOW TACKING ACROSS THE UPPER MS VALLEY ON SUNDAY WHILE A WEAK RIDGE EXTENDS NORTHWARD THROUGH NORTHERN ONTARIO TO OVER HUDSON BAY. ENERGY WITH THE SHORTWAVE WILL SPLIT TO BECOME A NORTHEASTWARD MOVING TROUGH AND AN EASTWARD MOVING CLOSED LOW. THE LOW WILL TRACK TOO FAR SOUTH OF THE CWA TO PROVIDE ANY GOOD SUPPORT FOR WIDESPREAD RAINFALL. MEANWHILE...THE MAIN TROUGH WILL CLIP THE WESTERN CWA WITH DECENT H7 FGEN AND MID-LEVEL Q-VECTOR CONVERGENCE. THE EAST HALF LOOKS TO MISS OUT ONCE AGAIN ON THE WIDESPREAD RAIN. HAVE DROPPED PRECIP WORDING COMPLETELY FROM THE FAR EAST...AND CUT BACK THE POPS ACROSS THE REST OF THE CWA. ONLY CHANCE OF SEEING A VERY ISOLATED RUMBLE OF THUNDER WOULD BE NEAR MENOMINEE...SO REMOVED THE SLIGHT CHANCE OF THUNDER PREVIOUSLY ALONG THE WI BORDER. MONDAY AND MONDAY NIGHT...SOME SUPPORT FROM THE SHORTWAVE ALONG WITH AN INCOMING UPPER JET WILL RESULT IN SCATTERED SHOWERS ACROSS THE CWA THROUGHOUT THE DAY. AGAIN...THE BEST CHANCE REMAINS OVER THE NORTHWEST CWA. AFTER A WEAK AND ELONGATED UPPER PV ANOMALY AND ASSOCIATED MID-LEVEL Q-VECTOR CONVERGENCE PUSH EAST MONDAY EVENING...INCREASING SUBSIDENCE SHOULD ALLOW FOR CLEARING ALOFT FOR THE WEST. WITH NO SOURCE OF LOW-LEVEL DRY AIR...FAIRLY LIGHT WINDS...AND RECENT RAINFALL...EXPECT LOW CLOUDS TO REMAIN AND PATCHY FOG TO FORM OVERNIGHT. FOG FORMATION WILL BE HEAVILY DEPENDENT ON HOW QUICK THE MID-LEVEL CLOUDS DEPART...SO DO NOT WANT TO GET TOO DETAILED IN SPECIFIC AREAS. FOR NOW...ADDED WORDING OF PATCHY FOG ACROSS THE INTERIOR WESTERN THIRD OF THE CWA WHERE CLEARING LOOKS TO BE MORE LIKELY. ALSO...WINDS WILL CONTINUE TO BACK TO A MORE NW WIND DIRECTION FOR THE WEST HALF...AND EVENTUALLY THE EAST HALF. THIS SHOULD LEAD TO SOME UPSLOPE DRIZZLE FORMATION ACROSS THE WEST AND CENTRAL FOR LOCATIONS PRONE TO NW UPSLOPE FLOW. TUESDAY...WAS INITIALLY GOING TO KEEP PRECIP OUT OF THE FORECAST...BUT ON SECOND GLANCE...A 100KT UPPER JET STREAK DIVING SOUTHEAST OVER UPPER MI SHOULD GIVE SOME SUPPORT FROM BOTH THE LEFT EXIT AND RIGHT ENTRANCE REGIONS. EXPECTATION IS THAT THE EXTRA LIFT UNDER THE JET WILL TAP INTO THE LITTLE REMAINING LOW-LEVEL MOISTURE AT THE SFC TO PRODUCE SOME ISOLATED SHOWERS IN THE MORNING...THEN SOME MORE DIURNALLY ENHANCED SHOWERS INLAND FOR THE AFTERNOON. WEDNESDAY AND THURSDAY...A QUICK-MOVING MID-LEVEL SHORTWAVE TROUGH WILL ROUND THE NORTHERN EXTENT OF A BUILDING RIDGE IN THE CENTRAL PLAINS ON WEDNESDAY. THIS TROUGH WILL BE PICKED UP BY AN ELONGATED TROUGH STRETCHING SOUTHWEST FROM A BROAD MID-LEVEL LOW OVER SOUTHERN QUEBEC. WHILE A BOUT OF MID-LEVEL Q-VECTOR CONVERGENCE PASSES OVER UPPER MI ON WEDNESDAY...MOISTURE WILL BE LACKING THROUGHOUT MUCH OF THE LAYER. MODEL TRENDS HAVE BEEN PUSHING FORCING AND ASSOCIATED PRECIP FARTHER SOUTH OVER THE PAST COUPLE DAYS...SO ALL BUT SOME MID TO HIGH CLOUDS ALONG THE WI BORDER SHOULD STAY CLEAR OF THE CWA. ONCE AGAIN...ON THURSDAY AFTERNOON...A WEAK UPPER PV ANOMALY AND MID-LEVEL SHORTWAVE TRACKING SOUTHEAST ACROSS THE CWA WILL STRUGGLE TO GENERATE EVEN MID TO HIGH-LEVEL CLOUDS GIVEN A DEEP DRY LAYER. FRIDAY AND SATURDAY...THE BUILDING RIDGE TO THE WEST WILL PUSH INTO THE REGION AND BRING DRY CONDITIONS FOR FRIDAY. THEN A SHORTWAVE TROUGH EJECTING FROM A DEEP TROUGH OVER THE WEST COAST WILL TRY TO RIDE OVER THE TOP OF THE RIDGE FRIDAY NIGHT INTO SATURDAY. IT REMAINS TO BE SEEN HOW MUCH THIS TROUGH WILL BE ABLE TO ERODE THE TOP OF THE RIDGE. FOR NOW...ENOUGH INSTABILITY AND MOISTURE SHOULD EXIST TO GENERATE SOME THUNDERSTORM ACTIVITY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 133 PM EDT SAT JUN 8 2013 EXPECT VFR CONDITIONS AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD AS DRY LOW-LEVEL AIR MASS REMAINS IN PLACE. DAYTIME HEATING AND WEAK INSTABILITY WILL KEEP A FEW -SHRA IN THE VCNTY AT KIWD INTO THE LATE AFTN/EARLY EVENING. EVEN AT KSAW...MAY SEE JUST ENOUGH INSTABILITY FOR A SHRA OR TWO IN THE VCNTY LATER THIS AFTN/EARLY EVENING. WINDS WILL REMAIN LIGHT THRU THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 406 PM EDT SAT JUN 8 2013 WITH HIGH PRESSURE MOVING OVER LAKE SUPERIOR AND HIGH OVERWATER STABILITY...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. THEN...A LOW PRESSURE SYSTEM MOVING E TO THE MID MISSISSIPPI VALLEY SUN NIGHT WILL TIGHTEN THE PRESSURE GRADIENT...RESULTING IN EASTERLY WINDS INCREASING UP TO 20KT SUN INTO EARLY MON. COASTAL CONVERGENCE COULD RESULT IN LOCALIZED HIGHER WINDS UP TO 25KT OVER FAR WRN LAKE SUPERIOR BTWN THE APOSTLE ISLANDS AND MN N SHORE SUN AFTN/EVENING. AS THE LOW SHIFTS E...ANOTHER WEAK HIGH PRES SYSTEM WILL SETTLE INTO THE UPPER GREAT LAKES TUE THRU THU...RESULTING IN WINDS UNDER 15KT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KLUBER AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
134 PM EDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM EDT SAT JUN 8 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GRT LKS DOWNSTREAM OF A RDG ALONG THE W COAST. THERE IS ALSO A RATHER WEAK UPR RDG OVER NW ONTARIO...WITH A 1015MB SFC HI CENTERED OVER WRN LK SUP. A SHRTWV IS DRIFTING SEWD THRU NCENTRAL MN ON THE SRN FLANK OF THIS RDG. THE INTERACTION BTWN THE DPVA/DEEP LYR QVECTOR CNVGC AND BAND OF H85 FGEN ON THE CYC SIDE OF 60KT H3 JET MAX SUPPORTING THE SHRTWV AND MID LVL MSTR SHOWN ON THE 00Z INL RAOB /KINX 29/ APPEARS TO BE GENERATING SOME ISOLD -SHRA OVER THE FAR WRN CWA PER RADAR RETURNS IN THAT AREA. BUT DRYNESS OF LLVLS SHOWN ON THE LOCAL 00Z RAOBS INDICATE AT LEAST SOME OF THIS PCPN MAY NOT BE REACHING THE GROUND. EXCEPT FOR SOME HI CLDS...THE REST OF THE CWA TO THE NE IS GENERALLY MOCLR WITH THE DRIER 00Z APX RAOB /KINX 16/ MORE REPRESENTATIVE OF CONDITIONS IN THIS AREA. FARTHER TO THE W... A RATHER POTENT SHRTWV IS DIGGING SEWD THRU THE NRN ROCKIES IN THE NW FLOW ALF BTWN THE W COAST RDG AND GREAT LKS TROF. MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND POPS ASSOCIATED WITH SHRTWV DRIFTING ESEWD THRU NRN MN. TODAY...SHRTWV RESPONSIBLE FOR ISOLD -SHRA OVER THE W EARLY THIS MRNG IS PROGGED TO DRIFT E ACRS NRN WI THIS MRNG AND THEN TO THE E THRU NRN LWR MI THIS AFTN...GIVING WAY TO DNVA/HGT RISES OVER UPR MI THIS AFTN. ALTHOUGH THIS CHAIN OF EVENTS WOULD INDICATE THE -SHRA NOW OVER THE W WL ALSO DRIFT TO THE E WITH THE SUPPORTING DYNAMIC SUPPORT WITH DRYING OVER THE W TAKING HOLD IN ITS WAKE...BULK OF NUMERICAL MODELS INDICATE THE ERN CWA WL REMAIN DRY THRU THE DAY WITH MORE ISOLD/SCT -SHRA DVLPG OVER THE INTERIOR W HALF WITH DAYTIME HEATING ON LK BREEZE BNDRYS THAT FORM IN THE WEAK LLVL FLOW ASSOCIATED WITH FLAT HI PRES. MODIFIED NAM FCST SDNG FOR IWD THIS AFTN FOR T/TD OF 70/44 YIELDS SBCAPE NEAR 200 J/KG WITH KINX OF 27...SO WL NOT INCLUDE ANY MENTION OF TS. NAM/GFS FCST SDNGS INDICATE THE LLVLS OVER THE E WL REMAIN TOO DRY TO SUPPORT PCPN...SO THIS SCENARIO SEEMS REASONABLE. THS SDNGS ALSO SHOW SOME MID LVL DRYING OVER THE W LATER IN THE AFTN WITH STRENGTHENING MID LVL INVRN UNDER THE DNVA...SO ANY -SHRA THERE SHOULD TEND TO DIMINISH LATER. MIXING TO H8-85 ON FCST SDNGS AND H85 TEMPS FCST ARND 9C SUPPORT HI TEMPS REACHING 70 TO 75 AWAY FM LK MODERATION. TONIGHT...CWA WL REMAIN UNDER THE INFLUENCE OF SHRTWV RDG AXIS TO THE E OF STRONG SHRTWV NOW IN THE NRN ROCKIES THAT IS FCST TO REACH FAR SW MN BY 12Z SUN. WITH THE STRONGLY NEGATIVE DYNAMICS AND WANING DAYTIME HEATING...ANY ISOLD -SHRA OVER THE W SHOULD DIMINISH QUICKLY EARLY IN THE EVNG AND GIVE WAY TO MOCLR SKIES. EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR E AS PRES GRADIENT/SE GRADIENT FLOW IS FCST TO SHARPEN LATE OVER THE W...WHERE SOME HI CLDS MAY ALSO ARRIVE LATE TO THE NE OF SHRTWV MOVING INTO MN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 414 AM EDT SAT JUN 8 2013 LARGER SCALE PATTERN PROGRESSION THROUGH THE NEXT WEEK LOOKS TO REMAIN ON THE SLOWER SIDE AS LARGER SCALE UPPER LEVEL FEATURES STAY SOMEWHAT BLOCKY. TROUGH OVER THE GREAT LAKES TO START THE LONG TERM BECOMES RE-INFORCED AS SHORTWAVE TROUGH DIGGING ACROSS THE ROCKIES SLIDES ACROSS CNTRL CONUS TO NORTHEAST CONUS THROUGH THURSDAY. THEN AS THIS LEADING TROUGH MOVES SLOWLY OUT OVER THE ATLANTIC AND ANOTHER TROUGH DIGS INTO NORTHWEST CONUS LATE IN THE WEEK...RIDGING WILL DEVELOP OVER THE CNTRL CONUS. MAIN RESULT WOULD BE TEMPERATURES TRENDING SLIGHTLY ABOVE NORMAL ACROSS UPPER MICHIGAN. PRIMARY CHANCE OF RAIN THROUGH THE PERIOD ARRIVES LATER SUNDAY INTO MONDAY AS SHORTWAVE TROUGH CROSSES THE REGION. FOCUSING IN ON THE RAIN CHANCES FOR SUNDAY AND SUNDAY NIGHT IT APPEARS THERE MAY BE CUTOFF FROM THE MORE WIDESPREAD RAIN OVER EASTERN CWA. ECMWF SHOWED THIS ON FRIDAY AND LATEST RUNS OF GFS/GEM-NH/UKMET PICK UP ON THIS AS WELL. 00Z NAM IS CONSISTENT WITH PREVIOUS RUNS AS IT IS FARTHER EAST AND CLOSED OFF WITH SHORTWAVE TROUGH BY 00Z MONDAY WHICH RESULTS IN SHOWERS SPREADING INTO EASTERN CWA BY THAT TIME. ECMWF/GFS NOW REPRESENTS MIDDLE GROUND WITH EASTERN EXTENT OF PRECIP AS NAM IS EASTERN OUTLIER WHILE GEM-NH AND UKMET WOULD BE WESTERN OUTLIERS AS THEY SHOW LITTLE QPF EVEN INTO CNTRL CWA BY 00Z MONDAY. ECMWF/GFS INDICATE SWATH OF H85-H7/H7-H5 Q-VECTOR CONVERGENCE INTO WEST HALF OF CWA BY 00Z MONDAY WITH H85-H7 MOISTURE TRANSPORT AIMED MOSTLY INTO WESTERN CWA ON SSE FLOW ARCING AHEAD OF SHORTWAVE TROUGH. PATTERN JUST DOES NOT SUPPORT MUCH RAIN MAKING IT INTO EASTERN CWA THROUGH SUNDAY NIGHT...ESPECIALLY SINCE LIFT WITH SHORTWAVE TROUGH SPLITS OVER TIME WITH ONE PIECE OF TROUGH LIFTING NORTHEAST INTO NORTHERN ONTARIO AND OTHER/STRONGER PIECE OF ENERGY DRIVING FROM CENTRAL MISSISSIPPI RIVER VALLEY INTO MIDWEST/OHIO VALLEY. KEPT GENERAL THEME OF PREVIOUS FORECAST...BUT WAS MORE STUBBORN TO BRING HIGHER POPS INTO THE EAST SUNDAY NIGHT AND MONDAY. WITH LESS CLOUDS AND SHRA OVER EAST ON SUNDAY NUDGED TEMPS INTO LOWER 70S THERE BUT KEPT READINGS OVER FAR SW/WEST IN LOWER 60S DUE TO EARLIER ONSET OF CLOUDS AND RAIN. LIKELY POPS OVER WEST AND CENTRAL STILL SEEM ON TRACK THOUGH TOTAL RAINFALL AMOUNTS WILL BE LIGHT IN MOST AREAS. SI/S LESS THAN 0C PEGGING TSRA OVER DAKOTAS CURRENTLY. SI/S MAINLY STAY ABOVE 0C INTO UPR MICHIGAN SUNDAY NIGHT...BUT FOLLOWING SREF 3HR PROBS FOR TSRA DID KEEP SMALL MENTION IN FAR SOUTH SUNDAY EVENING. EXPECT DECAYING SHOWERS MONDAY MORNING OVER THE CENTRAL CWA AS SPLITTING SHORTWAVE TROUGHS DAMPEN ENERGY AND MOISTURE TRANSPORT OVER CWA. SOME INDICATION THAT ADDITIONAL SHORTWAVE OR AT LEAST THE TAIL OF WAVE ON NOSE OF UPPER LEVEL JET AND WEAK SFC TROUGH CROSSING AREA MAY LEAD TO INCREASING SHRA MONDAY AFTN MAINLY WEST HALF INTERIOR. HEADED THAT WAY FOR POPS...LINGERING SMALL CHANCES OVR MAINLY CNTRL CWA MONDAY EVENING. DESPITE MOSTLY CLOUDY SKIES EXPECT TEMPS TO REACH MID-UPR 60S WHICH IS A BIT BLO NORMAL FOR THIS TIME OF YEAR. OTHER THAN ISOLD SHRA TUESDAY DUE TO SHORTWAVE AND WEAK MOISTURE ADVECTION MOVING THROUGH IN A FLATTER FLOW ALOFT...EXPECT QUIET WEATHER LATER MONDAY NIGHT THROUGH TUESDAY NIGHT. LIGHT NW WINDS WILL ALLOW AREAS JUST INLAND FROM LK SUPERIOR EAST OF MARQUETTE TO WARM INTO THE LOW EVEN MID 70S ON TUESDAY WITH H85 TEMPS NEAR +10C. AS RIDGING BUILDS ALOFT TUESDAY NIGHT INTO WEDNESDAY OVR CNTRL CONUS...BULGE OF WARM AIR WITH H85 TEMPS OVER +20C SPREADS ACROSS PLAINS TOWARD MISSOURI/MISSISSIPPI RIVER VALLEYS. SFC WARM FRONT STAYS TO SOUTH OF UPR LAKES AND H85 WARM FRONT FORECAST TO STAY OVER SOUTHERN PORTIONS OF MINNESOTA AND WISCONSIN. BASED ON H85 JET AND EDGE OF 1-6KM MUCAPE ALONG WITH H85-H3 THICKNESSES...SEEMS THAT SHRA/TSRA WILL REMAIN TO SOUTH OF UPR MICHIGAN ON WEDNESDAY. MIGHT BE CLOSE CALL THOUGH...ESPECIALLY IF SHORTWAVE PUSHING IN DURING THE DAY IS STRONG ENOUGH TO PUSH H85 WARM FRONT A BIT FARTHER NORTH AS MODELS WERE SHOWING EARLIER. JUST IN CASE MODELS JOG BACK NORTH AGAIN KEPT SLIGHT CHANCE POPS IN OVER THE SOUTH CWA. ONSHORE FLOW KEEPS IMMEDIATE LK SUPERIOR SHORE COOLER BUT INLAND AREAS WILL PUSH BACK INTO THE 70S AS LONG AS WARM FRONT SHRA/TSRA DO NOT COME TOO FAR NORTH. SHORTWAVE TROUGH MOVES ON THROUGH BY 12Z THURSDAY RESULTING IN SFC HIGH PRESSURE BUILDING OVERHEAD. ANOTHER WEAKER UPPER WAVE SLIPS IN LATE IN THE DAY BUT WILL REALLY BE LACKING MOISTURE. SLIGHT CHANCE OF A POP-UP SHRA OVER INTERIOR...BUT SHOULD BE QUITE ISOLD IF IT OCCURS AT ALL. NORTHERLY FLOW COMING OUT OF HIGH OVER ONTARIO WILL RESULT IN SIMILAR TEMP PATTERN TO WEDNESDAY WITH 60S NEAR LK SUPERIOR AND SOLID MID 70S INLAND. SFC HIGH MOVES TO THE EAST ON FRIDAY LEADING TO RETURN SOUTHERLY FLOW TO CLOSE THE WEEK. MOST OF THE MOISTURE AND FORCING FOR SHRA/TSRA MOST LIKELY STAYS OVR THE PLAINS SO JUST HAVE CONSENSUS SLIGHT CHANCE POPS FOR NOW. MAIN IMPACT WILL BE BETTER CHANCE OF WARMING INTO THE MID-UPR 70S EVEN OVER NORTH CWA NEAR LK SUPERIOR. IF THIS OCCURS...WOULD BE THE FIRST TIME OF SEEING WARMER THAN NORMAL TEMPS SINCE THE FEW SUMMER LIKE DAYS WE HAD TO CLOSE THE MONTH OF MAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 133 PM EDT SAT JUN 8 2013 EXPECT VFR CONDITIONS AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD AS DRY LOW-LEVEL AIR MASS REMAINS IN PLACE. DAYTIME HEATING AND WEAK INSTABILITY WILL KEEP A FEW -SHRA IN THE VCNTY AT KIWD INTO THE LATE AFTN/EARLY EVENING. EVEN AT KSAW...MAY SEE JUST ENOUGH INSTABILITY FOR A SHRA OR TWO IN THE VCNTY LATER THIS AFTN/EARLY EVENING. WINDS WILL REMAIN LIGHT THRU THE PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 414 AM EDT SAT JUN 8 2013 WITH HIGH PRESSURE MOVING OVER LAKE SUPERIOR AND HIGH OVERWATER STABILITY...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. A LOW PRESSURE SYSTEM MOVING THROUGH THE LOWER GREAT LAKES WILL TIGHTEN THE PRESSURE GRADIENT LATER IN THE WEEKEND...RESULTING IN E-SE WINDS INCREASING UP TO 20 KTS ON SUN INTO MON. AS ANOTHER HIGH MOVES TOWARD THE UPPER GREAT LAKES EARLY NEXT WEEK...WINDS SHOULD FALL BELOW 20 KTS LATER ON MON THRU WED. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...ROLFSON MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
733 AM EDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM EDT SAT JUN 8 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GRT LKS DOWNSTREAM OF A RDG ALONG THE W COAST. THERE IS ALSO A RATHER WEAK UPR RDG OVER NW ONTARIO...WITH A 1015MB SFC HI CENTERED OVER WRN LK SUP. A SHRTWV IS DRIFTING SEWD THRU NCENTRAL MN ON THE SRN FLANK OF THIS RDG. THE INTERACTION BTWN THE DPVA/DEEP LYR QVECTOR CNVGC AND BAND OF H85 FGEN ON THE CYC SIDE OF 60KT H3 JET MAX SUPPORTING THE SHRTWV AND MID LVL MSTR SHOWN ON THE 00Z INL RAOB /KINX 29/ APPEARS TO BE GENERATING SOME ISOLD -SHRA OVER THE FAR WRN CWA PER RADAR RETURNS IN THAT AREA. BUT DRYNESS OF LLVLS SHOWN ON THE LOCAL 00Z RAOBS INDICATE AT LEAST SOME OF THIS PCPN MAY NOT BE REACHING THE GROUND. EXCEPT FOR SOME HI CLDS...THE REST OF THE CWA TO THE NE IS GENERALLY MOCLR WITH THE DRIER 00Z APX RAOB /KINX 16/ MORE REPRESENTATIVE OF CONDITIONS IN THIS AREA. FARTHER TO THE W... A RATHER POTENT SHRTWV IS DIGGING SEWD THRU THE NRN ROCKIES IN THE NW FLOW ALF BTWN THE W COAST RDG AND GREAT LKS TROF. MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND POPS ASSOCIATED WITH SHRTWV DRIFTING ESEWD THRU NRN MN. TODAY...SHRTWV RESPONSIBLE FOR ISOLD -SHRA OVER THE W EARLY THIS MRNG IS PROGGED TO DRIFT E ACRS NRN WI THIS MRNG AND THEN TO THE E THRU NRN LWR MI THIS AFTN...GIVING WAY TO DNVA/HGT RISES OVER UPR MI THIS AFTN. ALTHOUGH THIS CHAIN OF EVENTS WOULD INDICATE THE -SHRA NOW OVER THE W WL ALSO DRIFT TO THE E WITH THE SUPPORTING DYNAMIC SUPPORT WITH DRYING OVER THE W TAKING HOLD IN ITS WAKE...BULK OF NUMERICAL MODELS INDICATE THE ERN CWA WL REMAIN DRY THRU THE DAY WITH MORE ISOLD/SCT -SHRA DVLPG OVER THE INTERIOR W HALF WITH DAYTIME HEATING ON LK BREEZE BNDRYS THAT FORM IN THE WEAK LLVL FLOW ASSOCIATED WITH FLAT HI PRES. MODIFIED NAM FCST SDNG FOR IWD THIS AFTN FOR T/TD OF 70/44 YIELDS SBCAPE NEAR 200 J/KG WITH KINX OF 27...SO WL NOT INCLUDE ANY MENTION OF TS. NAM/GFS FCST SDNGS INDICATE THE LLVLS OVER THE E WL REMAIN TOO DRY TO SUPPORT PCPN...SO THIS SCENARIO SEEMS REASONABLE. THS SDNGS ALSO SHOW SOME MID LVL DRYING OVER THE W LATER IN THE AFTN WITH STRENGTHENING MID LVL INVRN UNDER THE DNVA...SO ANY -SHRA THERE SHOULD TEND TO DIMINISH LATER. MIXING TO H8-85 ON FCST SDNGS AND H85 TEMPS FCST ARND 9C SUPPORT HI TEMPS REACHING 70 TO 75 AWAY FM LK MODERATION. TONIGHT...CWA WL REMAIN UNDER THE INFLUENCE OF SHRTWV RDG AXIS TO THE E OF STRONG SHRTWV NOW IN THE NRN ROCKIES THAT IS FCST TO REACH FAR SW MN BY 12Z SUN. WITH THE STRONGLY NEGATIVE DYNAMICS AND WANING DAYTIME HEATING...ANY ISOLD -SHRA OVER THE W SHOULD DIMINISH QUICKLY EARLY IN THE EVNG AND GIVE WAY TO MOCLR SKIES. EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR E AS PRES GRADIENT/SE GRADIENT FLOW IS FCST TO SHARPEN LATE OVER THE W...WHERE SOME HI CLDS MAY ALSO ARRIVE LATE TO THE NE OF SHRTWV MOVING INTO MN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 414 AM EDT SAT JUN 8 2013 LARGER SCALE PATTERN PROGRESSION THROUGH THE NEXT WEEK LOOKS TO REMAIN ON THE SLOWER SIDE AS LARGER SCALE UPPER LEVEL FEATURES STAY SOMEWHAT BLOCKY. TROUGH OVER THE GREAT LAKES TO START THE LONG TERM BECOMES RE-INFORCED AS SHORTWAVE TROUGH DIGGING ACROSS THE ROCKIES SLIDES ACROSS CNTRL CONUS TO NORTHEAST CONUS THROUGH THURSDAY. THEN AS THIS LEADING TROUGH MOVES SLOWLY OUT OVER THE ATLANTIC AND ANOTHER TROUGH DIGS INTO NORTHWEST CONUS LATE IN THE WEEK...RIDGING WILL DEVELOP OVER THE CNTRL CONUS. MAIN RESULT WOULD BE TEMPERATURES TRENDING SLIGHTLY ABOVE NORMAL ACROSS UPPER MICHIGAN. PRIMARY CHANCE OF RAIN THROUGH THE PERIOD ARRIVES LATER SUNDAY INTO MONDAY AS SHORTWAVE TROUGH CROSSES THE REGION. FOCUSING IN ON THE RAIN CHANCES FOR SUNDAY AND SUNDAY NIGHT IT APPEARS THERE MAY BE CUTOFF FROM THE MORE WIDESPREAD RAIN OVER EASTERN CWA. ECMWF SHOWED THIS ON FRIDAY AND LATEST RUNS OF GFS/GEM-NH/UKMET PICK UP ON THIS AS WELL. 00Z NAM IS CONSISTENT WITH PREVIOUS RUNS AS IT IS FARTHER EAST AND CLOSED OFF WITH SHORTWAVE TROUGH BY 00Z MONDAY WHICH RESULTS IN SHOWERS SPREADING INTO EASTERN CWA BY THAT TIME. ECMWF/GFS NOW REPRESENTS MIDDLE GROUND WITH EASTERN EXTENT OF PRECIP AS NAM IS EASTERN OUTLIER WHILE GEM-NH AND UKMET WOULD BE WESTERN OUTLIERS AS THEY SHOW LITTLE QPF EVEN INTO CNTRL CWA BY 00Z MONDAY. ECMWF/GFS INDICATE SWATH OF H85-H7/H7-H5 Q-VECTOR CONVERGENCE INTO WEST HALF OF CWA BY 00Z MONDAY WITH H85-H7 MOISTURE TRANSPORT AIMED MOSTLY INTO WESTERN CWA ON SSE FLOW ARCING AHEAD OF SHORTWAVE TROUGH. PATTERN JUST DOES NOT SUPPORT MUCH RAIN MAKING IT INTO EASTERN CWA THROUGH SUNDAY NIGHT...ESPECIALLY SINCE LIFT WITH SHORTWAVE TROUGH SPLITS OVER TIME WITH ONE PIECE OF TROUGH LIFTING NORTHEAST INTO NORTHERN ONTARIO AND OTHER/STRONGER PIECE OF ENERGY DRIVING FROM CENTRAL MISSISSIPPI RIVER VALLEY INTO MIDWEST/OHIO VALLEY. KEPT GENERAL THEME OF PREVIOUS FORECAST...BUT WAS MORE STUBBORN TO BRING HIGHER POPS INTO THE EAST SUNDAY NIGHT AND MONDAY. WITH LESS CLOUDS AND SHRA OVER EAST ON SUNDAY NUDGED TEMPS INTO LOWER 70S THERE BUT KEPT READINGS OVER FAR SW/WEST IN LOWER 60S DUE TO EARLIER ONSET OF CLOUDS AND RAIN. LIKELY POPS OVER WEST AND CENTRAL STILL SEEM ON TRACK THOUGH TOTAL RAINFALL AMOUNTS WILL BE LIGHT IN MOST AREAS. SI/S LESS THAN 0C PEGGING TSRA OVER DAKOTAS CURRENTLY. SI/S MAINLY STAY ABOVE 0C INTO UPR MICHIGAN SUNDAY NIGHT...BUT FOLLOWING SREF 3HR PROBS FOR TSRA DID KEEP SMALL MENTION IN FAR SOUTH SUNDAY EVENING. EXPECT DECAYING SHOWERS MONDAY MORNING OVER THE CENTRAL CWA AS SPLITTING SHORTWAVE TROUGHS DAMPEN ENERGY AND MOISTURE TRANSPORT OVER CWA. SOME INDICATION THAT ADDITIONAL SHORTWAVE OR AT LEAST THE TAIL OF WAVE ON NOSE OF UPPER LEVEL JET AND WEAK SFC TROUGH CROSSING AREA MAY LEAD TO INCREASING SHRA MONDAY AFTN MAINLY WEST HALF INTERIOR. HEADED THAT WAY FOR POPS...LINGERING SMALL CHANCES OVR MAINLY CNTRL CWA MONDAY EVENING. DESPITE MOSTLY CLOUDY SKIES EXPECT TEMPS TO REACH MID-UPR 60S WHICH IS A BIT BLO NORMAL FOR THIS TIME OF YEAR. OTHER THAN ISOLD SHRA TUESDAY DUE TO SHORTWAVE AND WEAK MOISTURE ADVECTION MOVING THROUGH IN A FLATTER FLOW ALOFT...EXPECT QUIET WEATHER LATER MONDAY NIGHT THROUGH TUESDAY NIGHT. LIGHT NW WINDS WILL ALLOW AREAS JUST INLAND FROM LK SUPERIOR EAST OF MARQUETTE TO WARM INTO THE LOW EVEN MID 70S ON TUESDAY WITH H85 TEMPS NEAR +10C. AS RIDGING BUILDS ALOFT TUESDAY NIGHT INTO WEDNESDAY OVR CNTRL CONUS...BULGE OF WARM AIR WITH H85 TEMPS OVER +20C SPREADS ACROSS PLAINS TOWARD MISSOURI/MISSISSIPPI RIVER VALLEYS. SFC WARM FRONT STAYS TO SOUTH OF UPR LAKES AND H85 WARM FRONT FORECAST TO STAY OVER SOUTHERN PORTIONS OF MINNESOTA AND WISCONSIN. BASED ON H85 JET AND EDGE OF 1-6KM MUCAPE ALONG WITH H85-H3 THICKNESSES...SEEMS THAT SHRA/TSRA WILL REMAIN TO SOUTH OF UPR MICHIGAN ON WEDNESDAY. MIGHT BE CLOSE CALL THOUGH...ESPECIALLY IF SHORTWAVE PUSHING IN DURING THE DAY IS STRONG ENOUGH TO PUSH H85 WARM FRONT A BIT FARTHER NORTH AS MODELS WERE SHOWING EARLIER. JUST IN CASE MODELS JOG BACK NORTH AGAIN KEPT SLIGHT CHANCE POPS IN OVER THE SOUTH CWA. ONSHORE FLOW KEEPS IMMEDIATE LK SUPERIOR SHORE COOLER BUT INLAND AREAS WILL PUSH BACK INTO THE 70S AS LONG AS WARM FRONT SHRA/TSRA DO NOT COME TOO FAR NORTH. SHORTWAVE TROUGH MOVES ON THROUGH BY 12Z THURSDAY RESULTING IN SFC HIGH PRESSURE BUILDING OVERHEAD. ANOTHER WEAKER UPPER WAVE SLIPS IN LATE IN THE DAY BUT WILL REALLY BE LACKING MOISTURE. SLIGHT CHANCE OF A POP-UP SHRA OVER INTERIOR...BUT SHOULD BE QUITE ISOLD IF IT OCCURS AT ALL. NORTHERLY FLOW COMING OUT OF HIGH OVER ONTARIO WILL RESULT IN SIMILAR TEMP PATTERN TO WEDNESDAY WITH 60S NEAR LK SUPERIOR AND SOLID MID 70S INLAND. SFC HIGH MOVES TO THE EAST ON FRIDAY LEADING TO RETURN SOUTHERLY FLOW TO CLOSE THE WEEK. MOST OF THE MOISTURE AND FORCING FOR SHRA/TSRA MOST LIKELY STAYS OVR THE PLAINS SO JUST HAVE CONSENSUS SLIGHT CHANCE POPS FOR NOW. MAIN IMPACT WILL BE BETTER CHANCE OF WARMING INTO THE MID-UPR 70S EVEN OVER NORTH CWA NEAR LK SUPERIOR. IF THIS OCCURS...WOULD BE THE FIRST TIME OF SEEING WARMER THAN NORMAL TEMPS SINCE THE FEW SUMMER LIKE DAYS WE HAD TO CLOSE THE MONTH OF MAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 732 AM EDT SAT JUN 8 2013 EVEN THOUGH THERE WL BE PLENTY OF MID CLDS THIS MRNG AND EVEN SOME -SHRA AT MAINLY IWD AND PERHAPS SAW INTO THE AFTN...EXPECT VFR CONDITIONS AT ALL THREE SITES THIS TAF PERIOD WITH DRY LLVLS SHOWN ON LOCAL 00Z RAOBS. ALTHOUGH LAKE BREEZES WILL DEVELOP THIS AFTN... WINDS SHOULD REMAIN LIGHT WITH WEAK HI PRES LINGERING OVER THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 414 AM EDT SAT JUN 8 2013 WITH HIGH PRESSURE MOVING OVER LAKE SUPERIOR AND HIGH OVERWATER STABILITY...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. A LOW PRESSURE SYSTEM MOVING THROUGH THE LOWER GREAT LAKES WILL TIGHTEN THE PRESSURE GRADIENT LATER IN THE WEEKEND...RESULTING IN E-SE WINDS INCREASING UP TO 20 KTS ON SUN INTO MON. AS ANOTHER HIGH MOVES TOWARD THE UPPER GREAT LAKES EARLY NEXT WEEK...WINDS SHOULD FALL BELOW 20 KTS LATER ON MON THRU WED. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
421 AM EDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM EDT SAT JUN 8 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GRT LKS DOWNSTREAM OF A RDG ALONG THE W COAST. THERE IS ALSO A RATHER WEAK UPR RDG OVER NW ONTARIO...WITH A 1015MB SFC HI CENTERED OVER WRN LK SUP. A SHRTWV IS DRIFTING SEWD THRU NCENTRAL MN ON THE SRN FLANK OF THIS RDG. THE INTERACTION BTWN THE DPVA/DEEP LYR QVECTOR CNVGC AND BAND OF H85 FGEN ON THE CYC SIDE OF 60KT H3 JET MAX SUPPORTING THE SHRTWV AND MID LVL MSTR SHOWN ON THE 00Z INL RAOB /KINX 29/ APPEARS TO BE GENERATING SOME ISOLD -SHRA OVER THE FAR WRN CWA PER RADAR RETURNS IN THAT AREA. BUT DRYNESS OF LLVLS SHOWN ON THE LOCAL 00Z RAOBS INDICATE AT LEAST SOME OF THIS PCPN MAY NOT BE REACHING THE GROUND. EXCEPT FOR SOME HI CLDS...THE REST OF THE CWA TO THE NE IS GENERALLY MOCLR WITH THE DRIER 00Z APX RAOB /KINX 16/ MORE REPRESENTATIVE OF CONDITIONS IN THIS AREA. FARTHER TO THE W... A RATHER POTENT SHRTWV IS DIGGING SEWD THRU THE NRN ROCKIES IN THE NW FLOW ALF BTWN THE W COAST RDG AND GREAT LKS TROF. MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND POPS ASSOCIATED WITH SHRTWV DRIFTING ESEWD THRU NRN MN. TODAY...SHRTWV RESPONSIBLE FOR ISOLD -SHRA OVER THE W EARLY THIS MRNG IS PROGGED TO DRIFT E ACRS NRN WI THIS MRNG AND THEN TO THE E THRU NRN LWR MI THIS AFTN...GIVING WAY TO DNVA/HGT RISES OVER UPR MI THIS AFTN. ALTHOUGH THIS CHAIN OF EVENTS WOULD INDICATE THE -SHRA NOW OVER THE W WL ALSO DRIFT TO THE E WITH THE SUPPORTING DYNAMIC SUPPORT WITH DRYING OVER THE W TAKING HOLD IN ITS WAKE...BULK OF NUMERICAL MODELS INDICATE THE ERN CWA WL REMAIN DRY THRU THE DAY WITH MORE ISOLD/SCT -SHRA DVLPG OVER THE INTERIOR W HALF WITH DAYTIME HEATING ON LK BREEZE BNDRYS THAT FORM IN THE WEAK LLVL FLOW ASSOCIATED WITH FLAT HI PRES. MODIFIED NAM FCST SDNG FOR IWD THIS AFTN FOR T/TD OF 70/44 YIELDS SBCAPE NEAR 200 J/KG WITH KINX OF 27...SO WL NOT INCLUDE ANY MENTION OF TS. NAM/GFS FCST SDNGS INDICATE THE LLVLS OVER THE E WL REMAIN TOO DRY TO SUPPORT PCPN...SO THIS SCENARIO SEEMS REASONABLE. THS SDNGS ALSO SHOW SOME MID LVL DRYING OVER THE W LATER IN THE AFTN WITH STRENGTHENING MID LVL INVRN UNDER THE DNVA...SO ANY -SHRA THERE SHOULD TEND TO DIMINISH LATER. MIXING TO H8-85 ON FCST SDNGS AND H85 TEMPS FCST ARND 9C SUPPORT HI TEMPS REACHING 70 TO 75 AWAY FM LK MODERATION. TONIGHT...CWA WL REMAIN UNDER THE INFLUENCE OF SHRTWV RDG AXIS TO THE E OF STRONG SHRTWV NOW IN THE NRN ROCKIES THAT IS FCST TO REACH FAR SW MN BY 12Z SUN. WITH THE STRONGLY NEGATIVE DYNAMICS AND WANING DAYTIME HEATING...ANY ISOLD -SHRA OVER THE W SHOULD DIMINISH QUICKLY EARLY IN THE EVNG AND GIVE WAY TO MOCLR SKIES. EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR E AS PRES GRADIENT/SE GRADIENT FLOW IS FCST TO SHARPEN LATE OVER THE W...WHERE SOME HI CLDS MAY ALSO ARRIVE LATE TO THE NE OF SHRTWV MOVING INTO MN. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 414 AM EDT SAT JUN 8 2013 LARGER SCALE PATTERN PROGRESSION THROUGH THE NEXT WEEK LOOKS TO REMAIN ON THE SLOWER SIDE AS LARGER SCALE UPPER LEVEL FEATURES STAY SOMEWHAT BLOCKY. TROUGH OVER THE GREAT LAKES TO START THE LONG TERM BECOMES RE-INFORCED AS SHORTWAVE TROUGH DIGGING ACROSS THE ROCKIES SLIDES ACROSS CNTRL CONUS TO NORTHEAST CONUS THROUGH THURSDAY. THEN AS THIS LEADING TROUGH MOVES SLOWLY OUT OVER THE ATLANTIC AND ANOTHER TROUGH DIGS INTO NORTHWEST CONUS LATE IN THE WEEK...RIDGING WILL DEVELOP OVER THE CNTRL CONUS. MAIN RESULT WOULD BE TEMPERATURES TRENDING SLIGHTLY ABOVE NORMAL ACROSS UPPER MICHIGAN. PRIMARY CHANCE OF RAIN THROUGH THE PERIOD ARRIVES LATER SUNDAY INTO MONDAY AS SHORTWAVE TROUGH CROSSES THE REGION. FOCUSING IN ON THE RAIN CHANCES FOR SUNDAY AND SUNDAY NIGHT IT APPEARS THERE MAY BE CUTOFF FROM THE MORE WIDESPREAD RAIN OVER EASTERN CWA. ECMWF SHOWED THIS ON FRIDAY AND LATEST RUNS OF GFS/GEM-NH/UKMET PICK UP ON THIS AS WELL. 00Z NAM IS CONSISTENT WITH PREVIOUS RUNS AS IT IS FARTHER EAST AND CLOSED OFF WITH SHORTWAVE TROUGH BY 00Z MONDAY WHICH RESULTS IN SHOWERS SPREADING INTO EASTERN CWA BY THAT TIME. ECMWF/GFS NOW REPRESENTS MIDDLE GROUND WITH EASTERN EXTENT OF PRECIP AS NAM IS EASTERN OUTLIER WHILE GEM-NH AND UKMET WOULD BE WESTERN OUTLIERS AS THEY SHOW LITTLE QPF EVEN INTO CNTRL CWA BY 00Z MONDAY. ECMWF/GFS INDICATE SWATH OF H85-H7/H7-H5 Q-VECTOR CONVERGENCE INTO WEST HALF OF CWA BY 00Z MONDAY WITH H85-H7 MOISTURE TRANSPORT AIMED MOSTLY INTO WESTERN CWA ON SSE FLOW ARCING AHEAD OF SHORTWAVE TROUGH. PATTERN JUST DOES NOT SUPPORT MUCH RAIN MAKING IT INTO EASTERN CWA THROUGH SUNDAY NIGHT...ESPECIALLY SINCE LIFT WITH SHORTWAVE TROUGH SPLITS OVER TIME WITH ONE PIECE OF TROUGH LIFTING NORTHEAST INTO NORTHERN ONTARIO AND OTHER/STRONGER PIECE OF ENERGY DRIVING FROM CENTRAL MISSISSIPPI RIVER VALLEY INTO MIDWEST/OHIO VALLEY. KEPT GENERAL THEME OF PREVIOUS FORECAST...BUT WAS MORE STUBBORN TO BRING HIGHER POPS INTO THE EAST SUNDAY NIGHT AND MONDAY. WITH LESS CLOUDS AND SHRA OVER EAST ON SUNDAY NUDGED TEMPS INTO LOWER 70S THERE BUT KEPT READINGS OVER FAR SW/WEST IN LOWER 60S DUE TO EARLIER ONSET OF CLOUDS AND RAIN. LIKELY POPS OVER WEST AND CENTRAL STILL SEEM ON TRACK THOUGH TOTAL RAINFALL AMOUNTS WILL BE LIGHT IN MOST AREAS. SI/S LESS THAN 0C PEGGING TSRA OVER DAKOTAS CURRENTLY. SI/S MAINLY STAY ABOVE 0C INTO UPR MICHIGAN SUNDAY NIGHT...BUT FOLLOWING SREF 3HR PROBS FOR TSRA DID KEEP SMALL MENTION IN FAR SOUTH SUNDAY EVENING. EXPECT DECAYING SHOWERS MONDAY MORNING OVER THE CENTRAL CWA AS SPLITTING SHORTWAVE TROUGHS DAMPEN ENERGY AND MOISTURE TRANSPORT OVER CWA. SOME INDICATION THAT ADDITIONAL SHORTWAVE OR AT LEAST THE TAIL OF WAVE ON NOSE OF UPPER LEVEL JET AND WEAK SFC TROUGH CROSSING AREA MAY LEAD TO INCREASING SHRA MONDAY AFTN MAINLY WEST HALF INTERIOR. HEADED THAT WAY FOR POPS...LINGERING SMALL CHANCES OVR MAINLY CNTRL CWA MONDAY EVENING. DESPITE MOSTLY CLOUDY SKIES EXPECT TEMPS TO REACH MID-UPR 60S WHICH IS A BIT BLO NORMAL FOR THIS TIME OF YEAR. OTHER THAN ISOLD SHRA TUESDAY DUE TO SHORTWAVE AND WEAK MOISTURE ADVECTION MOVING THROUGH IN A FLATTER FLOW ALOFT...EXPECT QUIET WEATHER LATER MONDAY NIGHT THROUGH TUESDAY NIGHT. LIGHT NW WINDS WILL ALLOW AREAS JUST INLAND FROM LK SUPERIOR EAST OF MARQUETTE TO WARM INTO THE LOW EVEN MID 70S ON TUESDAY WITH H85 TEMPS NEAR +10C. AS RIDGING BUILDS ALOFT TUESDAY NIGHT INTO WEDNESDAY OVR CNTRL CONUS...BULGE OF WARM AIR WITH H85 TEMPS OVER +20C SPREADS ACROSS PLAINS TOWARD MISSOURI/MISSISSIPPI RIVER VALLEYS. SFC WARM FRONT STAYS TO SOUTH OF UPR LAKES AND H85 WARM FRONT FORECAST TO STAY OVER SOUTHERN PORTIONS OF MINNESOTA AND WISCONSIN. BASED ON H85 JET AND EDGE OF 1-6KM MUCAPE ALONG WITH H85-H3 THICKNESSES...SEEMS THAT SHRA/TSRA WILL REMAIN TO SOUTH OF UPR MICHIGAN ON WEDNESDAY. MIGHT BE CLOSE CALL THOUGH...ESPECIALLY IF SHORTWAVE PUSHING IN DURING THE DAY IS STRONG ENOUGH TO PUSH H85 WARM FRONT A BIT FARTHER NORTH AS MODELS WERE SHOWING EARLIER. JUST IN CASE MODELS JOG BACK NORTH AGAIN KEPT SLIGHT CHANCE POPS IN OVER THE SOUTH CWA. ONSHORE FLOW KEEPS IMMEDIATE LK SUPERIOR SHORE COOLER BUT INLAND AREAS WILL PUSH BACK INTO THE 70S AS LONG AS WARM FRONT SHRA/TSRA DO NOT COME TOO FAR NORTH. SHORTWAVE TROUGH MOVES ON THROUGH BY 12Z THURSDAY RESULTING IN SFC HIGH PRESSURE BUILDING OVERHEAD. ANOTHER WEAKER UPPER WAVE SLIPS IN LATE IN THE DAY BUT WILL REALLY BE LACKING MOISTURE. SLIGHT CHANCE OF A POP-UP SHRA OVER INTERIOR...BUT SHOULD BE QUITE ISOLD IF IT OCCURS AT ALL. NORTHERLY FLOW COMING OUT OF HIGH OVER ONTARIO WILL RESULT IN SIMILAR TEMP PATTERN TO WEDNESDAY WITH 60S NEAR LK SUPERIOR AND SOLID MID 70S INLAND. SFC HIGH MOVES TO THE EAST ON FRIDAY LEADING TO RETURN SOUTHERLY FLOW TO CLOSE THE WEEK. MOST OF THE MOISTURE AND FORCING FOR SHRA/TSRA MOST LIKELY STAYS OVR THE PLAINS SO JUST HAVE CONSENSUS SLIGHT CHANCE POPS FOR NOW. MAIN IMPACT WILL BE BETTER CHANCE OF WARMING INTO THE MID-UPR 70S EVEN OVER NORTH CWA NEAR LK SUPERIOR. IF THIS OCCURS...WOULD BE THE FIRST TIME OF SEEING WARMER THAN NORMAL TEMPS SINCE THE FEW SUMMER LIKE DAYS WE HAD TO CLOSE THE MONTH OF MAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 120 AM EDT SAT JUN 8 2013 EXPECT VFR CONDITIONS AT ALL THREE SITES THROUGH THE TAF PERIOD...AS MID CLOUDS CONTINUE TO PERSIST NEAR KIWD. ALTHOUGH LAKE BREEZES WILL DEVELOP ON SATURDAY...WINDS SHOULD REMAIN LIGHT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 414 AM EDT SAT JUN 8 2013 WITH HIGH PRESSURE MOVING OVER LAKE SUPERIOR AND HIGH OVERWATER STABILITY...EXPECT LIGHT WINDS UNDER 20 KTS THRU TONIGHT. A LOW PRESSURE SYSTEM MOVING THROUGH THE LOWER GREAT LAKES WILL TIGHTEN THE PRESSURE GRADIENT LATER IN THE WEEKEND...RESULTING IN E-SE WINDS INCREASING UP TO 20 KTS ON SUN INTO MON. AS ANOTHER HIGH MOVES TOWARD THE UPPER GREAT LAKES EARLY NEXT WEEK...WINDS SHOULD FALL BELOW 20 KTS LATER ON MON THRU WED. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
620 PM CDT SUN JUN 9 2013 .AVIATION...00Z TAF ISSUANCE... RAIN SHOWERS AND/OR -DZ WILL CONTINUE THROUGH THIS EVENING WITH CONDITIONS DRYING OUT AT BRD FIRST...THEN HIB...DLH...HYR AND INL. WILL LIKELY SEE IFR FOG DEVELOP TONIGHT...WITH LOCALIZED AREAS OF LIFR VSBYS LATE TONIGHT/EARLY MON MORNING. CIGS WILL GRADUALLY LIFT THROUGH THE MORNING HOURS...WITH HIGH-END MVFR CIGS BY THE EARLY AFTERNOON...AND VFR BY THE MID TO LATE AFTERNOON. && .PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ SHORT TERM.../NOW - MONDAY/ THE FOCUS IS ON THE WIDESPREAD RAIN COVERING MUCH OF THE FORECAST AREA THIS AFTERNOON...AND HOW THAT WILL CONTINUE AND LINGER THROUGH TONIGHT. THE MODELS ARE IN FAIRLY GOOD AGREEMENT...BUT I HAVE AND CONTINUE TO LEAN ON THE HRRR SIMULATED REFLECTIVITY AS FAR TIMING OF THE PCPN THROUGH THIS EVENING GOES SINCE THE HRRR SEEMS TO BE DOING PRETTY WELL. AT 300PM/2000Z...HIGH PRESSURE STRETCHED FROM NEW YORK INTO THE EASTERN GREAT LAKES AND ONTARIO. A LOW PRESSURE SYSTEM WAS CENTERED NEAR NW IOWA...AND ANOTHER LOW PRESSURE SYSTEM IN CENTRAL SASKATCHEWAN. A TROUGH BOUNDARY EXTENDED FROM THE SASKATCHEWAN LOW THROUGH THE EASTERN DAKOTAS TO THE IOWA LOW. PLENTY OF MOISTURE WAS SURGING NORTHWARD AHEAD OF THE IOWA LOW AND THE TROUGH IN THE EASTERN DAKOTAS. THERE WAS WIDESPREAD LIGHT TO MODERATE RAIN ACROSS THE NORTHLAND. THERE WERE EASTERLY WINDS OF 5 TO 15 MPH. TEMPERATURES RANGED FROM THE MID TO LOWER 60S ACROSS THE SE AND FAR N FORECAST AREA...WHILE THE REST OF THE FORECAST AREA HAD TEMPERATURES IN THE LOW TO UPPER 50S DUE TO THE RAIN AND COOL WINDS OFF LAKE SUPERIOR. THROUGH TONIGHT...THE LOW IN NW IOWA WILL MOVE EAST TO NEAR SOUTHERN LAKE MICHIGAN BY LATE TONIGHT....WHILE THE TROUGH IN THE EASTERN DAKOTAS WILL SHIFT EAST TO THE EASTERN FORECAST AREA. HIGH PRESSURE WILL MOVE INTO THE PLAINS IN THE WAKE OF THE LOW AND TROUGH. THE RAIN SHOWERS ACROSS THE NORTHLAND SHOULD GENERALLY LIFT NORTH AND EASTWARD THIS AFTERNOON AND THEN GRADUALLY DIMINISH FROM WEST TO EAST TONIGHT. THE WINDS WILL WEAKEN AND BECOME NEGLIGIBLE LATER TONIGHT...MAKING FOG LIKELY FOR LATE TONIGHT AND INTO TOMORROW MORNING. OVERNIGHT LOWS SHOULD BE IN THE UPPER 40S TO MID 50S. MONDAY...WEAK HIGH PRESSURE WILL MOVE INTO THE NORTHLAND. THIS HELP KEEP MOST OF THE NORTHLAND DRY...BUT THERE COULD BE LINGERING RAIN SHOWERS/STORMS ACROSS THE EASTERN FORECAST AREA...AS WELL AS AFTERNOON SHOWERS/STORMS ACROSS THE NW FORECAST AREA THAT WOULD BE RELATED TO LOW PRESSURE MOVING ACROSS SOUTHERN MANITOBA. I HAVE SOME UNCERTAINTY ABOUT THE TEMPERATURE FORECAST. I RAISED THE FORECAST IN SOME AREAS BASED ON A BLEND OF THE LATEST GUIDANCE...BUT I THINK IT COULD BE EVEN WARMER IF THE NORTHLAND GETS ENOUGH SUNSHINE IN THE AFTERNOON. I SIDED A BIT ON THE CONSERVATIVE SIDE...ESPECIALLY SINCE THERE MAY BE MORNING FOG AND WE WILL HAVE TO SEE HOW WELL IT CLEARS CONSIDERING LITTLE WIND TO HELP MIX IT OUT. HOWEVER...IT AT LEAST LOOKS LIKE THE NORTHLAND WILL FINALLY GET SOME NEAR NORMAL TEMPERATURES AFTER COOLER THAN NORMAL WEATHER FOR SUCH A LONG TIME. LONG TERM.../MONDAY NIGHT - SUNDAY/ SURFACE HIGH PRESSURE WITH WEAK MID LEVEL RIDGING WILL MAKE A RETURN MONDAY NIGHT/TUESDAY. MEANWHILE THE A SHORT WAVE WILL TRACK EAST ALONG THE INTERNATIONAL BORDER AND INTO THE MN ARROWHEAD...SWEEPING A TROUGH OVER THE NORTHLAND. LATEST NAM BUFR SOUNDINGS SHOW VERY DRY PROFILES WITH RAPIDLY FALLING PWATS THROUGH TUESDAY MORNING...SO HAVE LIMITED POPS TO NRN ZONES...MAINLY MONDAY NIGHT...AND GONE WITH A DRY FCST OR JUST MENTION OF SPRINKLES ELSEWHERE TUESDAY. LONG TERM MODELS ARE IN GOOD OVERALL AGREEMENT THAT A H50 RIDGE AMPLIFIES OVER THE UPPER MIDWEST LATE THROUGH THE END OF THE WEEK WITH HIGH PRESSURE BUILDING OVER ONTARIO AND THE WESTERN GREAT LAKES. TEMPERATURES IN EXTENDED LOOK TO TREND TOWARDS MORE SEASONABLE VALUES WITH HIGHS IN THE 70S TO NEAR 80. HAVE KEPT A DRY FCST WED/THURS WITH GRADUALLY INCREASING POPS FROM THE WEST FRIDAY/SATURDAY AHEAD OF A COLD FRONT. AVIATION.../18Z TAF ISSUANCE/ WIDESPREAD RAIN WILL CONTINUE THOUGH THE REST OF THE AFTERNOON...BECOMING MORE SCATTERED IN NATURE AS THE EVENING WEARS ON. IFR TO LIFR CIGS WITH FOG AND -DZ WILL PREVAIL OVERNIGHT FOR MOST AREAS. THE EXCEPTION WILL BE OVER NORTHERN WISCONSIN /INCLUDING KHYR/ WHERE CIGS MAINLY IN THE VFR/MVFR CATEGORY WILL BE FOUND. SOME LIGHT FOG IS ALSO POSSIBLE OVER WISCONSIN WITH LOWER VSBYS. CONDITIONS ARE EXPECTED TO IMPROVE MONDAY MORNING...WITH GRADUALLY CLEARING SKIES FROM WEST TO EAST THROUGH THE DAY. && .POINT TEMPS/POPS... DLH 49 71 53 76 / 70 20 10 10 INL 50 72 53 75 / 70 20 40 10 BRD 51 75 56 79 / 30 10 10 10 HYR 55 77 55 80 / 60 20 10 10 ASX 51 71 50 76 / 70 30 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
347 PM CDT SAT JUN 8 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 200 PM CDT SAT JUN 8 2013 THE FORECAST OVER THE NEXT 12-24 HRS IS HIGHLY DEPENDENT ON WHETHER DRIER AIR ACROSS CENTRAL MN HOLDS...AND IF IT CONTINUES THE TREND OF DRIER MODEL RUNS IN THE SHORT TERM...KEEPING THE BULK OF THE PRECIPITATION ALONG THE IA/MN THRU 6Z. COMPLEX OF SHRA/ISOLD TSRA ACROSS FAR SW MN HAS ERODED SOME OF THE DRIER AIR THRU THE EARLY AFTN TODAY...BUT NOT ENOUGH TO HOLD ONTO LIKELY FOR AREAS NORTHWEST OF THE MN RIVER VALLEY UNTIL AFT 3Z/09...AND MOST LIKELY AFT 6-9Z BASED ON THE LATEST RAP TRENDS. IN ADDITION TO THE SLOWER MOVEMENT OF THE PRECIPITATION SHIELD TO THE NE OF MPX FA...THE SFC LOW HAS WEAKENED COMPARED TO SEVERAL MODEL RUNS AGO...AND IS MORE IN LINE OF THE EC THAT HAD THE SFC/UPPER LOW ACROSS NORTHERN IOWA A FEW DAYS AGO ON SUNDAY. THIS WOULD LEAD TO HEAVIER PRECIPITATION TOTALS ALONG THE MN/IA BORDER AND TSRA CHC/S TO A MINIMUM...OR UNTIL AFT 18Z SUNDAY DUE TO THE PROXIMITY OF THE COLDER AIR ALOFT FOR FAR EASTERN MN/WC WI. DUE TO THE SLOWER AND WEAKER SOLUTION OF THIS WX SYSTEM...PRECIPITATION AMTS MAY BE LOWER THAN EXPECTED ACROSS CENTRAL MN AND MORE CONCENTRATED ALONG THE MN/IA BORDER. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 343 PM CDT SAT JUN 8 2013 UPPER LOW AFFECTING MN/WI TONIGHT AND SUNDAY WILL DRIFT SOUTHEAST AND STILL BE OVER CENTRAL IOWA EARLY SUNDAY EVENING...WITH TROUGH AXIS STILL ALONG THE MN/WI BORDER MONDAY MORNING. 12Z DETERMINISTIC MODELS...ESPECIALLY THE 12Z NAM40...GEM AND ECMWF...KEEP A VERY WEAK GRADIENT ON MONDAY ACROSS ALL OF OUR CWA EXCEPT THE WESTERNMOST COUNTIES. 15Z SREF ALSO SUGGESTS A SIMILAR SCENARIO. WITH RAIN FOR MUCH OF SUNDAY AND TAPERING OFF SUNDAY EVENING...THINK THERE WILL BE A LOT OF LEFTOVER MOISTURE WITH LITTLE REASON FOR CLOUDS TO CLEAR ON MONDAY MORNING. IN FACT...WILL NOT BE SURPRISED TO SEE A COUPLE HOURS OF PARTIAL CLEARING ON MONDAY FOLLOWED BY LOTS OF CU DEVELOPMENT...WITH A DECREASE IN CLOUD COVER NOT REALLY HAPPENING UNTIL LATE MONDAY. THUS HAVE LOWERED TEMPS A BIT ON MONDAY. ONCE THE LOW DRIFTS BY...SYSTEMS BEGIN ARRIVING AT A FASTER PACE. UPPER RIDGE MOVES IN LATER ON MONDAY WITH DRY AND QUIET WEATHER. EASTERN AREAS WILL SEE THE COOLEST TEMPS MONDAY NIGHT WITH THE LONGEST PERIOD OF LIGHT WINDS AND MOSTLY CLEAR SKY. HAVE LOWER 50S FOR NOW BUT COULD IMAGINE SEEING SOME UPPER 40S. THERE IS SOME HINT A WEAK WAVE WILL CROSS MN TUESDAY MORNING IN ADVANCE OF THE NEXT RIDGE REACHING THE DAKOTAS. BUT THIS SHOULD JUST PRODUCE SOME MID/HIGH CLOUDS. WITH CLOUDS...WILL STICK WITH 50S FOR MIN TEMPS MONDAY NIGHT. MOST LIKELY TIMING FOR UPPER RIDGE TO BE OVER WESTERN MN IS TUESDAY AFTERNOON. BUT IT IS RATHER FLAT. A PAIR OF MORE SIGNIFICANT SHORT WAVES WILL ARRIVE TUESDAY NIGHT AND WEDNESDAY AFTERNOON. FIRST ONE WILL DAMPEN BUT THE SECOND ONE ON WEDNESDAY APPEARS TO MAINTAIN STRENGTH. BUT MN/WI SHOULD STILL BE IN THE COOL SECTOR WITH SHOWERS AND A FEW STORMS AS MAIN LOW TRACKS FROM THE CENTRAL PLAINS TOWARD INDIANA. DOES NOT REALLY LOOK LIKE A SEVERE THREAT AT THIS POINT FOR OUR AREA. TROUGH DEPARTS WED NIGHT WITH DRY WEATHER THURSDAY AS ANOTHER UPPER RIDGE APPROACHES. ECMWF...GEM AND GFS GENERALLY BRING IT OVER MN/WI FRIDAY AND SATURDAY. HOWEVER...IT ALSO LOOKS LIKE IT IS BEING FLATTENED AS LEAD SHORT WAVE FROM NEXT DEEP WESTERN TROUGH MOVES IN. THUS WILL HAVE MORE POPS FRIDAY INTO SATURDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1206 PM CDT SAT JUN 8 2013 THE MAIN AVIATION CONCERN IS THE DRY ATMOSPHERE INITIALLY ACROSS MOST OF THE FA WITH THE EXCEPTION IN THE FAR SW WHERE -SHRA HAD DEVELOPED NEAR CANBY/GRANITE FALLS/REDWOOD FALLS AND WINDOM PRIOR TO 17Z. REGIONAL RADAR HAS NOTED THE CIRCULATION ASSOCIATED WITH THE BAND OF SHRA MOVING ACROSS NW IOWA. ALTHOUGH THE ATMOSPHERE WILL BEGIN TO SATURATE DUE TO THIS SYSTEM...PRECIPITATION WILL LIKELY HOLD OFF UNTIL LATE THIS AFTN...WITH THE BULK OF THE SHRA AFT 6Z. LATEST SHORT TERM MODELS CONTINUED THE DRIER AIR ABV 85H IN CENTRAL/EC MN UNTIL AT LEAST 03Z...SO HAVE TRENDED WITH VFR CONDS UNTIL AFT 3Z...WILL THE EXCEPTION OF RWF. ONCE THE PRECIPITATION STARTS CONDS WILL DETERIORATE WITH IFR OR LIFR LIKELY AFT 9Z-15Z...WITH CIGS SLOWLY RISING SUNDAY AFTN...BUT REMAINING AT LEAST MVFR. WINDS WILL HOLD THRU MOST OF THE PERIOD FROM THE E/SE AND INCREASE DURING THE EVENING AS A STRONG LOW LEVEL JET DEVELOPS ACROSS SOUTHERN MN. LLWS IS LIKELY...ESPECIALLY WITH THE STRENGTH AND THE DIRECTIONAL TURNING IN THE LOWEST 1KM. KMSP... HELD OFF ON MVFR CIGS UNTIL AFT 6Z...WITH CIGS LOWERING TO IFR OR POSSIBLY LIFR AFT 9Z AS SHRA/+SHRA DEVELOP. TSRA CHC/S REMAIN TOO LOW TO INCLUDE VCTS...BUT THE BEST CHC OF TSRA WILL OCCUR AFT 9Z WITH A SLIGHTLY HIGHER CHC IN THE LATE MORNING/AFTN IF ANY BREAKS IN THE CLOUD COVER DEVELOPS. WINDS WILL REMAIN FROM THE SE...THEN BECOME MORE E/ESE TONIGHT AND INCREASING...AFT 15Z... SFC LOW WILL MOVE ACROSS SOUTHERN MN ALLOWING THE WINDS TO DECREASE SOME BEFORE SHIFTING TO THE NE/N BY SUNDAY EVENING. /OUTLOOK FOR KMSP/ SUN EVE...MVFR/IFR CIGS WITH OCNL SHRA DIMINISHING. WND BCMG N 5 KT. MON...MVFR CIGS IN THE MORNING...VFR BY AFTN. WND NW 5-10 KT. TUE...VFR. WIND LGT/VAR. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...JLT LONG TERM...TDK AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
210 PM CDT SAT JUN 8 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 200 PM CDT SAT JUN 8 2013 THE FORECAST OVER THE NEXT 12-24 HRS IS HIGHLY DEPENDENT ON WHETHER DRIER AIR ACROSS CENTRAL MN HOLDS...AND CONTINUES THE DRIER MODEL RUNS IN THE SHORT TERM...AND KEEPING THE BULK OF THE PRECIPITATION ALONG THE IA/MN THRU 6Z. COMPLEX OF SHRA/ISOLD TSRA ACROSS FAR SW MN HAS ERODED SOME OF THE DRIER AIR THRU THE EARLY AFTN TODAY...BUT NOT ENOUGH TO HOLD ONTO LIKELY FOR AREAS NORTHWEST OF THE MN RIVER VALLEY UNTIL AFT 3Z/09...AND MOST LIKELY AFT 6-9Z BASED ON THE LATEST RAP TRENDS. IN ADDITION TO THE SLOWER MOVEMENT OF THE PRECIPITATION SHIELD TO THE NE OF MPX FA...THE SFC LOW HAS WEAKENED COMPARED TO SEVERAL MODEL RUNS AGO...AND MORE IN LINE OF EC THAT HAD THE SFC/UPPER LOW ACROSS NORTHERN IOWA A FEW DAYS AGO ON SUNDAY. THIS WOULD LEAD TO HEAVIER PRECIPITATION TOTALS ALONG THE MN/IA BORDER AND TSRA CHC/S TO A MINIMAL...OR UNTIL AFT 18Z SUNDAY DUE TO THE PROXIMITY OF THE COLDER AIR ALOFT FOR FAR EASTERN MN/WC WI. DUE TO THE SLOWER AND WEAKER SOLUTION OF THIS WX SYSTEM...PRECIPITATION AMTS MAY BE LOWER THAN EXPECTED ACROSS CENTRAL MN AND MORE CONCENTRATED ALONG THE MN/IA BORDER. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 322 AM CDT SAT JUN 8 2013 LOW PRESSURE NEAR THE MN/IA BORDER WILL BE JUST ABOUT OCCLUDED BY SUNDAY MORNING. ARC OF SHOWERS AND THUNDERSTORMS WILL BE ONGOING AT THE START OF THE PERIOD FROM NRN IL NWD TO CENTRAL WI AND WWD ACROSS CENTRAL MN. THIS ARC WILL EVENTUALLY WEAKEN SUNDAY MORNING...BUT A COLD POCKET OF AIR IN THE MID LEVELS WILL FACILITATE MODESTLY STEEP LAPSE RATES BY SUNDAY AFTERNOON. LARGE VORT MAX OVERHEAD WILL SUSTAIN SCATTERED TO NUMEROUS THUNDERSTORM CLUSTERS ALL DAY. ALTHOUGH UNLIKELY...IT IS POSSIBLE A FEW BREAKS IN THE CLOUD COVER COULD ENHANCE INSTABILITY LOCALLY. GIVEN THE CLUSTERS OF STORMS AND THE POSSIBILITY OF POCKETS OF GREATER HEATING/INSTABILITY...THINK OUTFLOW BOUNDARIES WILL BE FAIRLY WIDESPREAD. THESE BOUNDARIES WILL SET OFF ADDITIONAL CLUSTERS...AND MAY LAY THE GROUNDWORK FOR NON-SUPERCELL TORNADO DEVELOPMENT SIMILAR TO THE SCENARIO THAT TRANSPIRED WEDNESDAY. MAINTAINED CATEGORICAL POPS SUNDAY...BUT IT DOES NOT LOOK LIKE ALL DAY RAINS. MBE VELOCITIES LESS THAN 10 KTS COULD ALSO BRING LOCALLY HEAVY RAIN. LOSS OF INSTABILITY AND THE LOW SINKING SOUTHEAST SHOULD END THE SHOWER/THUNDERSTORM CHANCES QUICKLY SUNDAY EVENING. INVERTED TROUGH WILL KEEP CLOUDS IN PLACE MONDAY MORNING BUT CLEARING IS FORECAST DURING THE AFTERNOON. THUS...SHOULD SEE TEMPERATURES REBOUND BACK INTO THE 70S. RIDGING REALLY BEGINS TO BUILD NORTHEAST TUESDAY. THICKNESSES OFF THE GFS/EURO RISE TOWARD 580 DAM OVER SWRN MN...NORMALLY INDICATING THE POTENTIAL FOR HOT TEMPERATURES. HOWEVER...925 MB TEMPS ARE ONLY AROUND +20C SO HIGHS SHOULD NOT GET MUCH ABOVE THE LOWER 80S. THE RELATIVELY COOL 925 MB TEMPS AND WARM THICKNESSES ALSO INDICATE STRONG CAPPING...THUS A DRY FORECAST. DISTURBANCE RIDING AROUND THE BUILDING PLAINS RIDGE WILL BEGIN TO SPILL SOUTHEAST INTO THE UPPER MISSISSIPPI VALLEY TUESDAY NIGHT/WEDNESDAY. KEPT POPS IN THE CHC CATEGORY DURING THIS TIME DUE TO UNCERTAINTIES WITH THE PLACEMENT OF FRONTAL FEATURES...BUT IT STILL APPEARS THE BEST RISK AREA WILL BE ACROSS SRN MN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1206 PM CDT SAT JUN 8 2013 THE MAIN AVIATION CONCERN IS THE DRY ATMOSPHERE INITIALLY ACROSS MOST OF THE FA WITH THE EXCEPTION IN THE FAR SW WHERE -SHRA HAD DEVELOPED NEAR CANBY/GRANITE FALLS/REDWOOD FALLS AND WINDOM PRIOR TO 17Z. REGIONAL RADAR HAS NOTED THE CIRCULATION ASSOCIATED WITH THE BAND OF SHRA MOVING ACROSS NW IOWA. ALTHOUGH THE ATMOSPHERE WILL BEGIN TO SATURATE DUE TO THIS SYSTEM...PRECIPITATION WILL LIKELY HOLD OFF UNTIL LATE THIS AFTN...WITH THE BULK OF THE SHRA AFT 6Z. LATEST SHORT TERM MODELS CONTINUED THE DRIER AIR ABV 85H IN CENTRAL/EC MN UNTIL AT LEAST 03Z...SO HAVE TRENDED WITH VFR CONDS UNTIL AFT 3Z...WILL THE EXCEPTION OF RWF. ONCE THE PRECIPITATION STARTS CONDS WILL DETERIORATE WITH IFR OR LIFR LIKELY AFT 9Z-15Z...WITH CIGS SLOWLY RISING SUNDAY AFTN...BUT REMAINING AT LEAST MVFR. WINDS WILL HOLD THRU MOST OF THE PERIOD FROM THE E/SE AND INCREASE DURING THE EVENING AS A STRONG LOW LEVEL JET DEVELOPS ACROSS SOUTHERN MN. LLWS IS LIKELY...ESPECIALLY WITH THE STRENGTH AND THE DIRECTIONAL TURNING IN THE LOWEST 1KM. KMSP... HELD OFF ON MVFR CIGS UNTIL AFT 6Z...WITH CIGS LOWERING TO IFR OR POSSIBLY LIFR AFT 9Z AS SHRA/+SHRA DEVELOP. TSRA CHC/S REMAIN TOO LOW TO INCLUDE VCTS...BUT THE BEST CHC OF TSRA WILL OCCUR AFT 9Z WITH A SLIGHTLY HIGHER CHC IN THE LATE MORNING/AFTN IF ANY BREAKS IN THE CLOUD COVER DEVELOPS. WINDS WILL REMAIN FROM THE SE...THEN BECOME MORE E/ESE TONIGHT AND INCREASING...AFT 15Z... SFC LOW WILL MOVE ACROSS SOUTHERN MN ALLOWING THE WINDS TO DECREASE SOME BEFORE SHIFTING TO THE NE/N BY SUNDAY EVENING. /OUTLOOK FOR KMSP/ SUN EVE...MVFR/IFR CIGS WITH OCNL SHRA DIMINISHING. WND BCMG N 5 KT. MON...MVFR CIGS IN THE MORNING...VFR BY AFTN. WND NW 5-10 KT. TUE...VFR. WIND LGT/VAR. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...JLT LONG TERM...BORGHOFF AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1223 PM CDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 322 AM CDT SAT JUN 8 2013 LONG RANGE 0.5 REFLECTIVITY INDICATING FAIRLY LARGE AREA OF LIGHT TO MODERATE SHOWERS...WITH A FEW EMBEDDED T-STORMS OVER EASTERN SODAK. ACTIVITY IS ASSOCIATED WITH A WARM FRONTAL BOUNDARY ATTACHED TO A SURFACE CYCLONE MIGRATING INTO EASTERN SODAK BY SUN/00Z TIME FRAME. USED HRRR FOR PLACEMENT OF MAINLY NON-TSTORM RAIN SHIELD OVER WESTERN THIRD OF CWA FOR REMAINDER OF MORNING HOURS. INCREASED POPS TO ACCOUNT FOR SLIGHTLY EARLIER INITIATION ACROSS THIS REGION FROM PREVIOUS FORECAST. GFS40 AND EUROPEAN SOMEWHAT SIMILAR IN MOVEMENT OF EVENTUAL STACKED 50H AND SURFACE SYSTEM BY SUN/12Z. DIFFERENCE BEING A SLIGHT DIP SOUTH OVER NW IA WITH A SLIGHTLY WEAKER SFC ELEMENT VS GFS40`S SLIGHTLY DEEPER SOLUTION OVER SW MN. EITHER WAY IT APPEARS LIKELY THAT A LARGE SWATH OF MAINLY LIGHT TO MODERATE SHOWERS WILL BE SEEN WEST OF A LINE FROM KAXN TO FAIRMONT LATE THIS MORNING INTO THE AFTERNOON HOURS. USED GFS40 ISENTROPIC ANALYSIS TO PROG TIMING AND POSITION OF CONVECTION INTO SATURDAY NIGHT. FORWARD PROGRESSION OF CONVECTION OVER REMAINDER OF FA WILL OCCUR THIS EVENING...WITH HEAVIER PRECIPITATION ANTICIPATED MAINLY SOUTH OF A LINE FROM REDWOOD FALLS TO RED WING. THIS WAS BASED ON BEST MOISTURE TRANSPORT VECTORS WHICH SHOULD CONTINUE INTO THE OVERNIGHT. IF THIS PANS OUT...COULD EASILY SEE A SOLID INCH OF MOISTURE OVER THIS AREA BY LATE TONIGHT. ANOTHER AREA WHICH COULD INCUR HEAVIER PRECIPITATION THIS EVENING THEN CURRENTLY PROGGED IS PORTIONS OF WEST CENTRAL MN...WHERE UP TO THREE QUARTERS OF AN INCH ARE POSSIBLE. TRIMMED HIGHS THIS AFTERNOON A FEW DEGREES TO ACCOUNT FOR BOTH INCREASING THICKNESS OF CLOUD DECK...AND DEVELOPING MOISTURE PATTERNS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 322 AM CDT SAT JUN 8 2013 LOW PRESSURE NEAR THE MN/IA BORDER WILL BE JUST ABOUT OCCLUDED BY SUNDAY MORNING. ARC OF SHOWERS AND THUNDERSTORMS WILL BE ONGOING AT THE START OF THE PERIOD FROM NRN IL NWD TO CENTRAL WI AND WWD ACROSS CENTRAL MN. THIS ARC WILL EVENTUALLY WEAKEN SUNDAY MORNING...BUT A COLD POCKET OF AIR IN THE MID LEVELS WILL FACILITATE MODESTLY STEEP LAPSE RATES BY SUNDAY AFTERNOON. LARGE VORT MAX OVERHEAD WILL SUSTAIN SCATTERED TO NUMEROUS THUNDERSTORM CLUSTERS ALL DAY. ALTHOUGH UNLIKELY...IT IS POSSIBLE A FEW BREAKS IN THE CLOUD COVER COULD ENHANCE INSTABILITY LOCALLY. GIVEN THE CLUSTERS OF STORMS AND THE POSSIBILITY OF POCKETS OF GREATER HEATING/INSTABILITY...THINK OUTFLOW BOUNDARIES WILL BE FAIRLY WIDESPREAD. THESE BOUNDARIES WILL SET OFF ADDITIONAL CLUSTERS...AND MAY LAY THE GROUNDWORK FOR NON-SUPERCELL TORNADO DEVELOPMENT SIMILAR TO THE SCENARIO THAT TRANSPIRED WEDNESDAY. MAINTAINED CATEGORICAL POPS SUNDAY...BUT IT DOES NOT LOOK LIKE ALL DAY RAINS. MBE VELOCITIES LESS THAN 10 KTS COULD ALSO BRING LOCALLY HEAVY RAIN. LOSS OF INSTABILITY AND THE LOW SINKING SOUTHEAST SHOULD END THE SHOWER/THUNDERSTORM CHANCES QUICKLY SUNDAY EVENING. INVERTED TROUGH WILL KEEP CLOUDS IN PLACE MONDAY MORNING BUT CLEARING IS FORECAST DURING THE AFTERNOON. THUS...SHOULD SEE TEMPERATURES REBOUND BACK INTO THE 70S. RIDGING REALLY BEGINS TO BUILD NORTHEAST TUESDAY. THICKNESSES OFF THE GFS/EURO RISE TOWARD 580 DAM OVER SWRN MN...NORMALLY INDICATING THE POTENTIAL FOR HOT TEMPERATURES. HOWEVER...925 MB TEMPS ARE ONLY AROUND +20C SO HIGHS SHOULD NOT GET MUCH ABOVE THE LOWER 80S. THE RELATIVELY COOL 925 MB TEMPS AND WARM THICKNESSES ALSO INDICATE STRONG CAPPING...THUS A DRY FORECAST. DISTURBANCE RIDING AROUND THE BUILDING PLAINS RIDGE WILL BEGIN TO SPILL SOUTHEAST INTO THE UPPER MISSISSIPPI VALLEY TUESDAY NIGHT/WEDNESDAY. KEPT POPS IN THE CHC CATEGORY DURING THIS TIME DUE TO UNCERTAINTIES WITH THE PLACEMENT OF FRONTAL FEATURES...BUT IT STILL APPEARS THE BEST RISK AREA WILL BE ACROSS SRN MN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1206 PM CDT SAT JUN 8 2013 THE MAIN AVIATION CONCERN IS THE DRY ATMOSPHERE INITIALLY ACROSS MOST OF THE FA WITH THE EXCEPTION IN THE FAR SW WHERE -SHRA HAD DEVELOPED NEAR CANBY/GRANITE FALLS/REDWOOD FALLS AND WINDOM PRIOR TO 17Z. REGIONAL RADAR HAS NOTED THE CIRCULATION ASSOCIATED WITH THE BAND OF SHRA MOVING ACROSS NW IOWA. ALTHOUGH THE ATMOSPHERE WILL BEGIN TO SATURATE DUE TO THIS SYSTEM...PRECIPITATION WILL LIKELY HOLD OFF UNTIL LATE THIS AFTN...WITH THE BULK OF THE SHRA AFT 6Z. LATEST SHORT TERM MODELS CONTINUED THE DRIER AIR ABV 85H IN CENTRAL/EC MN UNTIL AT LEAST 03Z...SO HAVE TRENDED WITH VFR CONDS UNTIL AFT 3Z...WILL THE EXCEPTION OF RWF. ONCE THE PRECIPITATION STARTS CONDS WILL DETERIORATE WITH IFR OR LIFR LIKELY AFT 9Z-15Z...WITH CIGS SLOWLY RISING SUNDAY AFTN...BUT REMAINING AT LEAST MVFR. WINDS WILL HOLD THRU MOST OF THE PERIOD FROM THE E/SE AND INCREASE DURING THE EVENING AS A STRONG LOW LEVEL JET DEVELOPS ACROSS SOUTHERN MN. LLWS IS LIKELY...ESPECIALLY WITH THE STRENGTH AND THE DIRECTIONAL TURNING IN THE LOWEST 1KM. KMSP... HELD OFF ON MVFR CIGS UNTIL AFT 6Z...WITH CIGS LOWERING TO IFR OR POSSIBLY LIFR AFT 9Z AS SHRA/+SHRA DEVELOP. TSRA CHC/S REMAIN TOO LOW TO INCLUDE VCTS...BUT THE BEST CHC OF TSRA WILL OCCUR AFT 9Z WITH A SLIGHTLY HIGHER CHC IN THE LATE MORNING/AFTN IF ANY BREAKS IN THE CLOUD COVER DEVELOPS. WINDS WILL REMAIN FROM THE SE...THEN BECOME MORE E/ESE TONIGHT AND INCREASING...AFT 15Z... SFC LOW WILL MOVE ACROSS SOUTHERN MN ALLOWING THE WINDS TO DECREASE SOME BEFORE SHIFTING TO THE NE/N BY SUNDAY EVENING. /OUTLOOK FOR KMSP/ SUN EVE...MVFR/IFR CIGS WITH OCNL SHRA DIMINISHING. WND BCMG N 5 KT. MON...MVFR CIGS IN THE MORNING...VFR BY AFTN. WND NW 5-10 KT. TUE...VFR. WIND LGT/VAR. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...AJZ LONG TERM...BORGHOFF AVIATION...JLT
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
704 AM CDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 322 AM CDT SAT JUN 8 2013 LONG RANGE 0.5 REFLECTIVITY INDICATING FAIRLY LARGE AREA OF LIGHT TO MODERATE SHOWERS...WITH A FEW EMBEDDED T-STORMS OVER EASTERN SODAK. ACTIVITY IS ASSOCIATED WITH A WARM FRONTAL BOUNDARY ATTACHED TO A SURFACE CYCLONE MIGRATING INTO EASTERN SODAK BY SUN/00Z TIME FRAME. USED HRRR FOR PLACEMENT OF MAINLY NON-TSTORM RAIN SHIELD OVER WESTERN THIRD OF CWA FOR REMAINDER OF MORNING HOURS. INCREASED POPS TO ACCOUNT FOR SLIGHTLY EARLIER INITIATION ACROSS THIS REGION FROM PREVIOUS FORECAST. GFS40 AND EUROPEAN SOMEWHAT SIMILAR IN MOVEMENT OF EVENTUAL STACKED 50H AND SURFACE SYSTEM BY SUN/12Z. DIFFERENCE BEING A SLIGHT DIP SOUTH OVER NW IA WITH A SLIGHTLY WEAKER SFC ELEMENT VS GFS40`S SLIGHTLY DEEPER SOLUTION OVER SW MN. EITHER WAY IT APPEARS LIKELY THAT A LARGE SWATH OF MAINLY LIGHT TO MODERATE SHOWERS WILL BE SEEN WEST OF A LINE FROM KAXN TO FAIRMONT LATE THIS MORNING INTO THE AFTERNOON HOURS. USED GFS40 ISENTROPIC ANALYSIS TO PROG TIMING AND POSITION OF CONVECTION INTO SATURDAY NIGHT. FORWARD PROGRESSION OF CONVECTION OVER REMAINDER OF FA WILL OCCUR THIS EVENING...WITH HEAVIER PRECIPITATION ANTICIPATED MAINLY SOUTH OF A LINE FROM REDWOOD FALLS TO RED WING. THIS WAS BASED ON BEST MOISTURE TRANSPORT VECTORS WHICH SHOULD CONTINUE INTO THE OVERNIGHT. IF THIS PANS OUT...COULD EASILY SEE A SOLID INCH OF MOISTURE OVER THIS AREA BY LATE TONIGHT. ANOTHER AREA WHICH COULD INCUR HEAVIER PRECIPITATION THIS EVENING THEN CURRENTLY PROGGED IS PORTIONS OF WEST CENTRAL MN...WHERE UP TO THREE QUARTERS OF AN INCH ARE POSSIBLE. TRIMMED HIGHS THIS AFTERNOON A FEW DEGREES TO ACCOUNT FOR BOTH INCREASING THICKNESS OF CLOUD DECK...AND DEVELOPING MOISTURE PATTERNS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 322 AM CDT SAT JUN 8 2013 LOW PRESSURE NEAR THE MN/IA BORDER WILL BE JUST ABOUT OCCLUDED BY SUNDAY MORNING. ARC OF SHOWERS AND THUNDERSTORMS WILL BE ONGOING AT THE START OF THE PERIOD FROM NRN IL NWD TO CENTRAL WI AND WWD ACROSS CENTRAL MN. THIS ARC WILL EVENTUALLY WEAKEN SUNDAY MORNING...BUT A COLD POCKET OF AIR IN THE MID LEVELS WILL FACILITATE MODESTLY STEEP LAPSE RATES BY SUNDAY AFTERNOON. LARGE VORT MAX OVERHEAD WILL SUSTAIN SCATTERED TO NUMEROUS THUNDERSTORM CLUSTERS ALL DAY. ALTHOUGH UNLIKELY...IT IS POSSIBLE A FEW BREAKS IN THE CLOUD COVER COULD ENHANCE INSTABILITY LOCALLY. GIVEN THE CLUSTERS OF STORMS AND THE POSSIBILITY OF POCKETS OF GREATER HEATING/INSTABILITY...THINK OUTFLOW BOUNDARIES WILL BE FAIRLY WIDESPREAD. THESE BOUNDARIES WILL SET OFF ADDITIONAL CLUSTERS...AND MAY LAY THE GROUNDWORK FOR NON-SUPERCELL TORNADO DEVELOPMENT SIMILAR TO THE SCENARIO THAT TRANSPIRED WEDNESDAY. MAINTAINED CATEGORICAL POPS SUNDAY...BUT IT DOES NOT LOOK LIKE ALL DAY RAINS. MBE VELOCITIES LESS THAN 10 KTS COULD ALSO BRING LOCALLY HEAVY RAIN. LOSS OF INSTABILITY AND THE LOW SINKING SOUTHEAST SHOULD END THE SHOWER/THUNDERSTORM CHANCES QUICKLY SUNDAY EVENING. INVERTED TROUGHINESS WILL KEEP CLOUDS IN PLACE MONDAY MORNING BUT CLEARING IS FORECAST DURING THE AFTERNOON. THUS...SHOULD SEE TEMPERATURES REBOUND BACK INTO THE 70S. RIDGING REALLY BEGINS TO BUILD NORTHEAST TUESDAY. THICKNESSES OFF THE GFS/EURO RISE TOWARD 580 DAM OVER SWRN MN...NORMALLY INDICATING THE POTENTIAL FOR HOT TEMPERATURES. HOWEVER...925 MB TEMPS ARE ONLY AROUND +20C SO HIGHS SHOULD NOT GET MUCH ABOVE THE LOWER 80S. THE RELATIVELY COOL 925 MB TEMPS AND WARM THICKNESSES ALSO INDICATE STRONG CAPPING...THUS A DRY FORECAST. DISTURBANCE RIDING AROUND THE BUILDING PLAINS RIDGE WILL BEGIN TO SPILL SOUTHEAST INTO THE UPPER MISSISSIPPI VALLEY TUESDAY NIGHT/WEDNESDAY. KEPT POPS IN THE CHC CATEGORY DURING THIS TIME DUE TO UNCERTAINTIES WITH THE PLACEMENT OF FRONTAL FEATURES...BUT IT STILL APPEARS THE BEST RISK AREA WILL BE ACROSS SRN MN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 641 AM CDT SAT JUN 8 2013 VFR CONDITIONS EXPECTED UNTIL AT LEAST THE MIDDLE OF THIS AFTERNOON. BATCH OF SHOWERS AND THUNDERSTORMS ARE ONGOING THIS MORNING ACROSS FAR SERN SD. ADDITIONAL SHOWERS WILL EVENTUALLY WORK NORTHEAST WITH TIME TODAY...IMPACTING RWF FIRST AND MSP/STC/RNH THIS EVENING. PERIOD OF MODERATE/HVY RAIN POSSIBLE LATE TONIGHT SOUTH OF I-94 WITH EMBEDDED THUNDER. IFR CIGS POSSIBLE BY THE END OF THE PERIOD. KMSP...VFR THROUGH THE EARLY EVENING...THEN DETERIORATING CONDITIONS THEREAFTER AS THE RAIN ADVANCES IN FROM THE SOUTH. BEST ESTIMATE OF HEAVIEST RAINFALL IS BETWEEN 08-14Z WITH THUNDER ALSO POSSIBLE. /OUTLOOK FOR KMSP/ SUN...MVFR/IFR CIGS WITH OCNL TSRA DIMINISHING BY EVENING. WIND BCMG N 5 KT. MON...MVFR CIGS IN THE MORNING...VFR BY AFTERNOON. WIND NW 5-10 KT. TUE...VFR. WIND LGT/VAR. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...AJZ LONG TERM...BORGHOFF AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
408 AM CDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 322 AM CDT SAT JUN 8 2013 LONG RANGE 0.5 REFLECTIVITY INDICATING FAIRLY LARGE AREA OF LIGHT TO MODERATE SHOWERS...WITH A FEW EMBEDDED T-STORMS OVER EASTERN SODAK. ACTIVITY IS ASSOCIATED WITH A WARM FRONTAL BOUNDARY ATTACHED TO A SURFACE CYCLONE MIGRATING INTO EASTERN SODAK BY SUN/00Z TIME FRAME. USED HRRR FOR PLACEMENT OF MAINLY NON-TSTORM RAIN SHIELD OVER WESTERN THIRD OF CWA FOR REMAINDER OF MORNING HOURS. INCREASED POPS TO ACCOUNT FOR SLIGHTLY EARLIER INITIATION ACROSS THIS REGION FROM PREVIOUS FORECAST. GFS40 AND EUROPEAN SOMEWHAT SIMILAR IN MOVEMENT OF EVENTUAL STACKED 50H AND SURFACE SYSTEM BY SUN/12Z. DIFFERENCE BEING A SLIGHT DIP SOUTH OVER NW IA WITH A SLIGHTLY WEAKER SFC ELEMENT VS GFS40`S SLIGHTLY DEEPER SOLUTION OVER SW MN. EITHER WAY IT APPEARS LIKELY THAT A LARGE SWATH OF MAINLY LIGHT TO MODERATE SHOWERS WILL BE SEEN WEST OF A LINE FROM KAXN TO FAIRMONT LATE THIS MORNING INTO THE AFTERNOON HOURS. USED GFS40 ISENTROPIC ANALYSIS TO PROG TIMING AND POSITION OF CONVECTION INTO SATURDAY NIGHT. FORWARD PROGRESSION OF CONVECTION OVER REMAINDER OF FA WILL OCCUR THIS EVENING...WITH HEAVIER PRECIPITATION ANTICIPATED MAINLY SOUTH OF A LINE FROM REDWOOD FALLS TO RED WING. THIS WAS BASED ON BEST MOISTURE TRANSPORT VECTORS WHICH SHOULD CONTINUE INTO THE OVERNIGHT. IF THIS PANS OUT...COULD EASILY SEE A SOLID INCH OF MOISTURE OVER THIS AREA BY LATE TONIGHT. ANOTHER AREA WHICH COULD INCUR HEAVIER PRECIPITATION THIS EVENING THEN CURRENTLY PROGGED IS PORTIONS OF WEST CENTRAL MN...WHERE UP TO THREE QUARTERS OF AN INCH ARE POSSIBLE. TRIMMED HIGHS THIS AFTERNOON A FEW DEGREES TO ACCOUNT FOR BOTH INCREASING THICKNESS OF CLOUD DECK...AND DEVELOPING MOISTURE PATTERNS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 322 AM CDT SAT JUN 8 2013 LOW PRESSURE NEAR THE MN/IA BORDER WILL BE JUST ABOUT OCCLUDED BY SUNDAY MORNING. ARC OF SHOWERS AND THUNDERSTORMS WILL BE ONGOING AT THE START OF THE PERIOD FROM NRN IL NWD TO CENTRAL WI AND WWD ACROSS CENTRAL MN. THIS ARC WILL EVENTUALLY WEAKEN SUNDAY MORNING...BUT A COLD POCKET OF AIR IN THE MID LEVELS WILL FACILITATE MODESTLY STEEP LAPSE RATES BY SUNDAY AFTERNOON. LARGE VORT MAX OVERHEAD WILL SUSTAIN SCATTERED TO NUMEROUS THUNDERSTORM CLUSTERS ALL DAY. ALTHOUGH UNLIKELY...IT IS POSSIBLE A FEW BREAKS IN THE CLOUD COVER COULD ENHANCE INSTABILITY LOCALLY. GIVEN THE CLUSTERS OF STORMS AND THE POSSIBILITY OF POCKETS OF GREATER HEATING/INSTABILITY...THINK OUTFLOW BOUNDARIES WILL BE FAIRLY WIDESPREAD. THESE BOUNDARIES WILL SET OFF ADDITIONAL CLUSTERS...AND MAY LAY THE GROUNDWORK FOR NON-SUPERCELL TORNADO DEVELOPMENT SIMILAR TO THE SCENARIO THAT TRANSPIRED WEDNESDAY. MAINTAINED CATEGORICAL POPS SUNDAY...BUT IT DOES NOT LOOK LIKE ALL DAY RAINS. MBE VELOCITIES LESS THAN 10 KTS COULD ALSO BRING LOCALLY HEAVY RAIN. LOSS OF INSTABILITY AND THE LOW SINKING SOUTHEAST SHOULD END THE SHOWER/THUNDERSTORM CHANCES QUICKLY SUNDAY EVENING. INVERTED TROUGHINESS WILL KEEP CLOUDS IN PLACE MONDAY MORNING BUT CLEARING IS FORECAST DURING THE AFTERNOON. THUS...SHOULD SEE TEMPERATURES REBOUND BACK INTO THE 70S. RIDGING REALLY BEGINS TO BUILD NORTHEAST TUESDAY. THICKNESSES OFF THE GFS/EURO RISE TOWARD 580 DAM OVER SWRN MN...NORMALLY INDICATING THE POTENTIAL FOR HOT TEMPERATURES. HOWEVER...925 MB TEMPS ARE ONLY AROUND +20C SO HIGHS SHOULD NOT GET MUCH ABOVE THE LOWER 80S. THE RELATIVELY COOL 925 MB TEMPS AND WARM THICKNESSES ALSO INDICATE STRONG CAPPING...THUS A DRY FORECAST. DISTURBANCE RIDING AROUND THE BUILDING PLAINS RIDGE WILL BEGIN TO SPILL SOUTHEAST INTO THE UPPER MISSISSIPPI VALLEY TUESDAY NIGHT/WEDNESDAY. KEPT POPS IN THE CHC CATEGORY DURING THIS TIME DUE TO UNCERTAINTIES WITH THE PLACEMENT OF FRONTAL FEATURES...BUT IT STILL APPEARS THE BEST RISK AREA WILL BE ACROSS SRN MN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1036 PM CDT FRI JUN 7 2013 FORECAST REASONING HAS NOT CHANGED MUCH FROM THE 00Z DISCUSSION. THE EXCEPTION BEING THE DEGREE TO WHICH THE CLOUDS OVER THE AREA HAVE DISSIPATED THIS EVENING... BUT THEY WERE VFR ANYWAY SO THE IMPACTS OF THE EARLIER SCATTERING OUT WERE MINIMAL. OTHERWISE... FORECAST IS SIMILAR TO THE PREVIOUS SET OF TAFS... WITH CONDITIONS STARTING TO DETERIORATE BY SATURDAY AFTERNOON... THEN MORE SIGNIFICANT DETERIORATION SATURDAY NIGHT AS THE SHORTWAVE OVER THE NORTHERN ROCKIES WORKS INTO THE REGION AND HELPS DRIVE A SURFACE LOW FROM THE NORTHERN PLAINS TOWARD MINNESOTA AND IOWA. MODEL GUIDANCE IS STILL A BIT VARIED IN HOW THINGS WILL SHAPE UP SATURDAY NIGHT WITH RESPECT TO WHERE THE WIDESPREAD/STEADY PCPN WILL OCCUR NORTH OF THE SURFACE WAVE. PRIOR TO THAT... IT STILL APPEARS A BAND OF WARM ADVECTION PCPN WILL SWING ACROSS THE AREA DURING THE DAY ON SATURDAY... ALTHOUGH IT IS TOUGH TO PIN DOWN WHERE/WHEN THAT WILL OCCUR SO CONTINUED TO STICK WITH VCSH OR MOST OF THE TAFS AT THIS POINT. FOR THE LATER MORE WIDESPREAD LOWER CEILINGS AND PCPN... HIT THINGS HARDER ACROSS THE SOUTHERN PART OF THE AREA... WHERE MORE OF THE GUIDANCE SEEMS TO BE IN AGREEMENT... AND INCLUDED A MENTION OF REDUCED VISIBILITIES AS WELL. KMSP...PRIMARY UNCERTAINTIES IN THE FORECAST ARE THE TIMING OF THE ARRIVAL OF PCPN ON SATURDAY AND THE EVENTUAL MVFR CEILINGS. AT THIS POINT THINGS COULD EASILY VARY BY SEVERAL HOURS FROM WHAT IS FORECAST... AND CEILINGS COULD ALSO WIND UP BEING 1+K FT ABOVE/BELOW WHAT IS SUGGESTED FOR SATURDAY NIGHT. WINDS COULD BECOME AN ISSUE SATURDAY OVERNIGHT AS WELL WITH SOME LLWS A POSSIBILITY IF THE LOW LEVEL JET SETS UP AS SUGGESTED BY MODEL GUIDANCE AHEAD OF THE UPPER TROUGH AND SURFACE LOW... SO THAT WILL NEED TO BE MONITORED. /OUTLOOK FOR KMSP/ SUNDAY...MVFR CEILINGS AND VISIBILITIES EXPECTED WITH SHRA/TSRA... IFR CONDITIONS POSSIBLE. SOUTHEAST WIND 10 TO 20 KT BECOMING LIGHT AND VARIABLE. SUNDAY NIGHT...MVFR CEILINGS AND VISIBILITIES POSSIBLE. CHANCE OF SHRA. LIGHT AND VARIABLE WIND BECOMING NORTHEAST AROUND 5 KT. MONDAY...MVFR CEILINGS POSSIBLE EARLY. NORTHEAST WIND AROUND 5 KT BECOMING NORTHWEST 5 TO 15 KT. MONDAY NIGHT...VFR CONDITIONS EXPECTED. LIGHT AND VARIABLE WIND. TUESDAY...VFR CONDITIONS EXPECTED. LIGHT AND VARIABLE WIND BECOMING EAST 5 TO 10 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...AJZ LONG TERM...BORGHOFF AVIATION...
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
850 PM MDT Sun Jun 9 2013 .DISCUSSION... Update forthcoming. Generally quiet and benign conditions expected overnight. The exception to this picture, as was the case last night, is weak short wave energy moving along the Canadian border and additional short wave energy over portions of southwest Montana. An isolated thunderstorm is possible over these areas. HRRR analysis suggests this activity should end by 07z. Temperatures look reasonable but have tweaked lows for Great Falls and Lewistown. Emanuel && .AVIATION... Updated 2350Z. VFR conditions will continue across north central/central/southwest Montana at least through Monday. Weak disturbances moving east along the Canadian border and across far southwest Montana will keep areas of mid level cloudiness with isolated showers/thunderstorms in those areas through around 03Z. However, there is only a low possibility that storms will directly impact the nearby terminals of KCTB/KHVR in the north and KBZN in the south. Otherwise, breezy and gusty northwesterly winds will diminish through 03Z, as skies become mostly clear. The airmass becomes weakly unstable again across southwest Montana after 18Z Monday, for a slightly better chance that isolated thunderstorms may impact the KBZN terminal. Coulston && .PREV DISCUSSION...Issued 256 PM MDT Sun Jun 9 2013 Tonight through Tuesday...Generally quiet but breezy weather will continue this evening. However, once again this evening, there will be a slight chance of a shower or thunderstorm at opposite ends of the CWA: near the Canadian border and near Yellowstone Park. On Monday, an upper level wave will move through the Great Basin with flow aloft over the CWA backing around to the southwest by evening. The airmass also becomes unstable over far southwest Montana during the afternoon and evening with scattered thunderstorms developing over the mountains. This convection will move to the northeast into central Montana overnight and expand in coverage. There is also some indication that a mesoscale complex could form over central Montana during the overnight hours. Showers and thunderstorms become likely across much of the forecast area on Tuesday. From Tuesday evening through Wednesday afternoon there is some risk that a few thunderstorms may become strong to borderline severe with gusty winds being the main threat. mpj Tuesday night through Sunday...a rather unsettled weather pattern will reside over the region from much of the second half of the work week. A rather strong upper level disturbance is expected to develop over Central MT early Tue evening. Some of the storms could be on the strong side Tue evening. Thus pops have been raised for a good portion of North Central MT. Another round of storms will affect the region Wednesday into Thursday ahead the main cold front and upper level trof. Expect the precipitation to become a bit more widespread by Thursday over North Central MT. This heavier precip later in the week will slow down the rivers receding in Hill and Blaine counties. Colder air will move into the region by Thursday night...thus snow levels will be lowering into the 6500 to 7500 feet range. Expect some snow at higher elevations by Friday morning...but any snow accumulations should be minor. For Saturday...expect drier near seasonable temperatures to move back into the region. By next Sunday...a southwesterly flow develop aloft resulting in a chance for afternoon thunderstorms over Central and Southwest MT by late in the day. Brusda && .HYDROLOGY... Small streams and creeks remain high and out of their banks across a large portion of Central and North Central Montana. Areal flood warnings will continue for Hill/Blaine/Fergus Counties. Point flood warnings remain in effect for three locations: Big Sandy Creek near Havre, Clear Creek near Chinook, and the Milk River near Harlem. These points are expected to remain near or above flood stage into at least the early part of this week. The potential exists Tuesday for significant rain over areas currently under flood warnings. && .PRELIMINARY POINT TEMPS/POPS... GTF 47 74 48 72 / 0 0 30 40 CTB 41 71 44 70 / 10 10 10 40 HLN 49 79 50 77 / 0 10 30 40 BZN 45 81 47 77 / 10 20 30 50 WEY 42 78 41 71 / 20 30 30 40 DLN 48 82 49 76 / 0 30 40 50 HVR 46 74 49 72 / 10 0 20 50 LWT 46 72 48 69 / 0 0 40 70 && .TFX WATCHES/WARNINGS/ADVISORIES... Flood Warning through Monday morning for Blaine, Fergus, and Hill Counties. Flood Warning until further notice for Big Sandy Creek near Havre, Clear Creek near Chinook, and the Milk River near Harlem. && $$ weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1044 PM MDT Fri Jun 7 2013 ...UPDATE TO AVIATION... .DISCUSSION... Update forthcoming. An upper trof continues to push across eastern Montana this evening. The airmass remains the most unstable across the east with decent CAPE values and available moisture. The result has been scattered thunderstorms moving along the Hi-Line and across portions of North Central and eastern Montana. Latest RUC analysis indicates convective activity should end by 08z. Temperatures look reasonable. Emanuel && .AVIATION... Updated 0444Z. VFR conditions will prevail through the forecast period. Winds will increase overnight across the eastern part of the area. Scattered showers and thunderstorms will be possible along a line east of KHVR and KLWT. Most shower activity should remain to to the east of these sites so will not use VCTS or -TSRA however some development could create brief TS near KHVR and KLWT. Drying conditions should develop by 12Z. Suk && .PREV DISCUSSION...ISSUED 252 PM MDT Fri Jun 7 2013 Tonight through Sunday...The main weather during the period will be associated with a weather disturbance aloft which will move southeast across Montana tonight. The better lift and moisture will be over the plains and associated mountains while southwest Montana will see little if any lift and little moisture. Will thus continue with the idea of the highest chances of precipitation near the Canadian border and the lowest over far southwest Montana. As far as the threat of stronger thunderstorms for this evening goes will restrict the threat to northcentral Montana where there will be the best combination of lift and instability. At this time think any hail that develops will be less than a half-inch and any wind gusts less than 50 mph. For Saturday and Sunday expect a dry period as an upper ridge moves into the Pacific Northwest Saturday and through the forecast area on Sunday. The only possible exception will be over the far north where there will be some moisture Saturday into Saturday night. However the airmass will be stable so any precipitation that does develop will be light. Blank Sunday night through Friday...High pressure ridge dominating factor early in the forecast period. Current models show energy moving in from the west mostly being steered to the north and around Montana. Exception is one small weather system that will try to slip under the ridge clipping southwest Montana Monday night and Tuesday. Next Pacific low pressure trough starts to push inland on Wednesday. At this time...appears this system will maintain enough structure and strength to move through north central and southwest Montana Wednesday night and Thursday. Models have some differences in tracking of trough with GFS moving it through more quickly and putting the best chance for precipitation over north central Montana. ECMWF is trending slower and while core of precipitation with this model is also north, it also indicates a chance of some rain over southwest Montana. Thunderstorms a definite possibility during the afternoon and evening hours during the period. Temperatures throughout the period will generally be near to slightly above seasonal averages. && .HYDROLOGY... Small streams and creeks remain high and out of their banks across a large portion of central and north central Montana. Areal flood warnings will continue for Hill/Blaine/Fergus Counties. Point flood warnings remain in effect for three locations: Big Sandy Creek near Havre, Clear Creek near Chinook, and the Milk River near Harlem. These points are expected to remain near or above flood stage into next week. Scattered showers and thunderstorms will fall over the flooded areas tonight...but precipitation should be light and should not significantly affect runoff. && .PRELIMINARY POINT TEMPS/POPS... GTF 49 72 46 78 / 20 10 10 0 CTB 49 71 44 75 / 50 10 10 0 HLN 53 76 48 82 / 20 0 0 0 BZN 46 75 42 82 / 20 0 0 0 WEY 39 71 36 75 / 10 0 0 0 DLN 46 75 44 82 / 10 0 0 0 HVR 53 72 48 77 / 60 10 10 0 LWT 49 68 44 74 / 30 10 10 0 && .TFX WATCHES/WARNINGS/ADVISORIES... Flood Warning through Monday morning for Blaine, Fergus, and Hill Counties. Flood Warning until further notice for Big Sandy Creek near Havre, Clear Creek near Chinook, and the Milk River near Harlem. && $$ weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1228 PM CDT SAT JUN 8 2013 .AVIATION...18Z TAFS FOR KOFK...KOMA AND KLNK. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED THE FIRST FEW HOURS OF THE TAF CYCLE WITH SOUTHEASTERLY SFC WINDS. INSTABILITY IS EXPECTED TO INCREASE THIS AFTERNOON ONCE WE SEE SOME BREAKS IN THE CLOUDS LEADING TO INCREASED CHANCES FOR TSRA. HAVE INCLUDED THESE IN TEMPO GROUPS LATE THIS AFTERNOON AND EARLY THIS EVENING ALONG A COLD FRONT. WINDS WILL TURN TO THE WEST/NORTHWEST BEHIND THIS FRONT. ADDITIONAL SHOWERS ARE POSSIBLE...ESPECIALLY AT KOFK SUNDAY MORNING BEHIND THIS SYSTEM. KERN && .PREV DISCUSSION... /ISSUED 1021 AM CDT SAT JUN 8 2013/ UPDATE... COMPLEX FORECAST TODAY WITH ONGOING CONVECTION ACROSS THE AREA DROPPING SOME POCKETS OF MODERATE RAINFALL. RAP AND HRRR SEEM TO HAVE THE BEST HANDLE ON THE MORNING ACTIVITY. REGIONAL RADAR MOSIAC SHOWS THE ACTIVITY BECOMING MUCH MORE WIDELY SCATTERED TO THE WEST WHICH LEADS TO SOME POSSIBILTY OF BREAKING OUT OF THE CLOUD COVER THIS AFTERNOON. 12Z UPPER AIR ANALYSIS SHOWS AREA OF 500MB HEIGHT FALLS OVER EASTERN MONTANA AND WYOMING WHICH WILL DROP SOUTHEAST THROUGHOUT THE DAY PROVIDING AREA FOR BROAD ASCENT LATER THIS AFTERNOON AND THIS EVENING. THE BIG CONDITION FOR AFTERNOON/EVENING CONVECTION IS CURRENT CLOUD COVER LIMITING SFC HEATING. IF WE ARE ABLE TO BREAK OUT...WE DO EXPECT THUNDERSTORMS TO DEVELOP LATE THIS AFTERNOON AND CONTINUE INTO THE EARLY EVENING AS THE LATEST RAP/HRRR INDICATE. LOW LEVEL MOSIT ADVECTION AND AN INCREASING LOW LEVEL JET THIS EVENING MAY LEAD TO SOME HEAVY RAIN. KERN .PREV DISCUSSION... /ISSUED 333 AM CDT SAT JUN 8 2013/ DISCUSSION... MAIN FORECAST ISSUES ARE THUNDERSTORM CHANCES...SOME SEVERE WEATHER THREAT AND POTENTIAL FOR HEAVY RAIN TODAY AND TONIGHT. UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB A JET SEGMENT OF AROUND 125 KNOTS WAS PUNCHING SOUTHEAST FROM SOUTHWEST BRITISH COLUMBIA. AT 500 MB...SHORTWAVE ENERGY WAS MOVING TOWARD THE REGION FROM THE NORTHWEST. 12 HOUR HEIGHT FALLS OF AROUND 50 METERS AT 500 MB WERE NOTED FROM THE SOUTHERN PARTS OF ALBERTA/SASKATCHEWAN DOWN INTO MONTANA. WARM AIR ADVECTION WAS TAKING PLACE AT 700 MB AND 850 MB...ALONG WITH SOME INCREASE IN MOISTURE ACROSS THE HIGH PLAINS. IT APPEARED THAT THE MODELS INITIALIZED 850 MB MOISTURE A LITTLE HIGHER THAN REALITY. TODAY AND TONIGHT...BELIEVE THERE IS SOME SEVERE WEATHER THREAT ESPECIALLY THIS AFTERNOON AND EVENING. MODELS SHOW GENERALLY 25-35 KNOTS OF 0-6 KM BULK SHEAR AND BL CAPE VALUES UP TO ABOUT 1500 J/KG. PRECIPITABLE WATER VALUES SHOULD INCREASE TO AROUND 1.50 INCHES... AND WARM CLOUD DEPTH WILL BE INCREASING. SO STORMS WILL BE FAIRLY EFFICIENT AT PRODUCING PCPN. 00Z RUNS OF GFS AND ECMWF INDICATED 850 MB DEWPOINTS REACHING 10-13 DEGREES C BY EVENING. NAM WAS SIMILAR OR SLIGHTLY HIGHER ACROSS ABOUT THE SOUTHEAST HALF OF THE FORECAST AREA BY 00Z...BUT BROUGHT SOME DRIER AIR INTO NORTHEAST NEBRASKA BY EVENING. DID NOT GO WITH A FLASH FLOOD WATCH FOR ANY AREAS JUST YET...BUT DID MENTION HEAVY RAIN. DAY SHIFT CAN LOOK AT THAT MORE LATER. CURRENT SHOWERS/TSTMS TO OUR WEST SHOULD CONTINUE TO DROP EWD/SEWD THIS MORNING. CLOUD COVER AND PCPN WILL LIMIT HEATING AT LEAST SOMEWHAT...ESPECIALLY ACROSS NORTHEAST NEBRASKA WHERE KEPT HIGHS IN THE LOWER OR MID 70S. FARTHER SOUTH...LOCATIONS NEAR THE KANSAS AND MISSOURI BORDERS COULD REACH AROUND 80. STORMS SHOULD BE FAIRLY WIDESPREAD BY LATE AFTERNOON/EARLY EVENING OVER THE SOUTHEAST HALF OF THE AREA...WITH CHANCES GENERALLY DECREASING FROM NORTHWEST TO SOUTHEAST TONIGHT. THE ONE EXCEPTION TO THIS IS ACROSS THE FAR NORTHERN ZONES. A CLOSED LOW SHOULD BE SOMEWHERE NEAR THE NEBRASKA/IOWA/SOUTH DAKOTA BORDER BY 12Z SUNDAY. SHOWERS AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE NEAR THIS SYSTEM THROUGH THE DAY SUNDAY. INCREASED POPS AND QPF A LITTLE FOR AREAS NORTH AND NORTHEAST OF OMAHA. PCPN IS NOT LIKELY TO LINGER MUCH PAST 7 PM...SO LEFT THE FORECAST DRY FOR SUNDAY NIGHT. MONDAY INTO FRIDAY...A MID LEVEL RIDGE SHOULD BUILD EASTWARD ACROSS THE NORTHERN AND CENTRAL PLAINS MONDAY/TUESDAY. LEFT BOTH DAY PERIODS DRY...BUT WE COULD SEE A FEW STORMS MONDAY NIGHT ASSOCIATED WITH MOISTURE RETURN AND 40-50 KNOT LOW LEVEL JET. SEVERAL PIECES OF SHORTWAVE ENERGY WILL MOVE ACROSS THE PLAINS FROM TUESDAY NIGHT INTO FRIDAY...BUT THESE WILL BE DIFFICULT TO TIME. BEST BET FOR STORMS IN THAT PERIOD WOULD BE FROM LATE AFTERNOON INTO THE OVERNIGHT HOURS. HIGHS FROM TUESDAY INTO FRIDAY SHOULD BE MOSTLY 80S AND LOWER 90S... WITH LOWS IN THE 60S TO LOWER 70S. MILLER && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1021 AM CDT SAT JUN 8 2013 .UPDATE... COMPLEX FORECAST TODAY WITH ONGOING CONVECTION ACROSS THE AREA DROPPING SOME POCKETS OF MODERATE RAINFALL. RAP AND HRRR SEEM TO HAVE THE BEST HANDLE ON THE MORNING ACTIVITY. REGIONAL RADAR MOSIAC SHOWS THE ACTIVITY BECOMING MUCH MORE WIDELY SCATTERED TO THE WEST WHICH LEADS TO SOME POSSIBILTY OF BREAKING OUT OF THE CLOUD COVER THIS AFTERNOON. 12Z UPPER AIR ANALYSIS SHOWS AREA OF 500MB HEIGHT FALLS OVER EASTERN MONTANA AND WYOMING WHICH WILL DROP SOUTHEAST THROUGHOUT THE DAY PROVIDING AREA FOR BROAD ASCENT LATER THIS AFTERNOON AND THIS EVENING. THE BIG CONDITION FOR AFTERNOON/EVENING CONVECTION IS CURRENT CLOUD COVER LIMITING SFC HEATING. IF WE ARE ABLE TO BREAK OUT...WE DO EXPECT THUNDERSTORMS TO DEVELOP LATE THIS AFTERNOON AND CONTINUE INTO THE EARLY EVENING AS THE LATEST RAP/HRRR INDICATE. LOW LEVEL MOSIT ADVECTION AND AN INCREASING LOW LEVEL JET THIS EVENING MAY LEAD TO SOME HEAVY RAIN. KERN && .PREV DISCUSSION... /ISSUED 713 AM CDT SAT JUN 8 2013/ AVIATION... 12Z TAFS FOR KOMA...KLNK...KOFK. PERIODS OF THUNDERSTORMS EXPECTED THROUGH MUCH OF THE FORECAST AS COLD FRONT APPROACHES THE AREA...OTHWERWISE VFR CONDITIONS OUTSIDE THUNDERSTORMS. PREV DISCUSSION... /ISSUED 333 AM CDT SAT JUN 8 2013/ DISCUSSION... MAIN FORECAST ISSUES ARE THUNDERSTORM CHANCES...SOME SEVERE WEATHER THREAT AND POTENTIAL FOR HEAVY RAIN TODAY AND TONIGHT. UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB .A JET SEGMENT OF AROUND 125 KNOTS WAS PUNCHING SOUTHEAST FROM SOUTHWEST BRITISH COLUMBIA. AT 500 MB...SHORTWAVE ENERGY WAS MOVING TOWARD THE REGION FROM THE NORTHWEST. 12 HOUR HEIGHT FALLS OF AROUND 50 METERS AT 500 MB WERE NOTED FROM THE SOUTHERN PARTS OF ALBERTA/SASKATCHEWAN DOWN INTO MONTANA. WARM AIR ADVECTION WAS TAKING PLACE AT 700 MB AND 850 MB...ALONG WITH SOME INCREASE IN MOISTURE ACROSS THE HIGH PLAINS. IT APPEARED THAT THE MODELS INITIALIZED 850 MB MOISTURE A LITTLE HIGHER THAN REALITY. TODAY AND TONIGHT...BELIEVE THERE IS SOME SEVERE WEATHER THREAT ESPECIALLY THIS AFTERNOON AND EVENING. MODELS SHOW GENERALLY 25-35 KNOTS OF 0-6 KM BULK SHEAR AND BL CAPE VALUES UP TO ABOUT 1500 J/KG. PRECIPITABLE WATER VALUES SHOULD INCREASE TO AROUND 1.50 INCHES... AND WARM CLOUD DEPTH WILL BE INCREASING. SO STORMS WILL BE FAIRLY EFFICIENT AT PRODUCING PCPN. 00Z RUNS OF GFS AND ECMWF INDICATED 850 MB DEWPOINTS REACHING 10-13 DEGREES C BY EVENING. NAM WAS SIMILAR OR SLIGHTLY HIGHER ACROSS ABOUT THE SOUTHEAST HALF OF THE FORECAST AREA BY 00Z...BUT BROUGHT SOME DRIER AIR INTO NORTHEAST NEBRASKA BY EVENING. DID NOT GO WITH A FLASH FLOOD WATCH FOR ANY AREAS JUST YET...BUT DID MENTION HEAVY RAIN. DAY SHIFT CAN LOOK AT THAT MORE LATER. CURRENT SHOWERS/TSTMS TO OUR WEST SHOULD CONTINUE TO DROP EWD/SEWD THIS MORNING. CLOUD COVER AND PCPN WILL LIMIT HEATING AT LEAST SOMEWHAT...ESPECIALLY ACROSS NORTHEAST NEBRASKA WHERE KEPT HIGHS IN THE LOWER OR MID 70S. FARTHER SOUTH...LOCATIONS NEAR THE KANSAS AND MISSOURI BORDERS COULD REACH AROUND 80. STORMS SHOULD BE FAIRLY WIDESPREAD BY LATE AFTERNOON/EARLY EVENING OVER THE SOUTHEAST HALF OF THE AREA...WITH CHANCES GENERALLY DECREASING FROM NORTHWEST TO SOUTHEAST TONIGHT. THE ONE EXCEPTION TO THIS IS ACROSS THE FAR NORTHERN ZONES. A CLOSED LOW SHOULD BE SOMEWHERE NEAR THE NEBRASKA/IOWA/SOUTH DAKOTA BORDER BY 12Z SUNDAY. SHOWERS AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE NEAR THIS SYSTEM THROUGH THE DAY SUNDAY. INCREASED POPS AND QPF A LITTLE FOR AREAS NORTH AND NORTHEAST OF OMAHA. PCPN IS NOT LIKELY TO LINGER MUCH PAST 7 PM...SO LEFT THE FORECAST DRY FOR SUNDAY NIGHT. MONDAY INTO FRIDAY...A MID LEVEL RIDGE SHOULD BUILD EASTWARD ACROSS THE NORTHERN AND CENTRAL PLAINS MONDAY/TUESDAY. LEFT BOTH DAY PERIODS DRY...BUT WE COULD SEE A FEW STORMS MONDAY NIGHT ASSOCIATED WITH MOISTURE RETURN AND 40-50 KNOT LOW LEVEL JET. SEVERAL PIECES OF SHORTWAVE ENERGY WILL MOVE ACROSS THE PLAINS FROM TUESDAY NIGHT INTO FRIDAY...BUT THESE WILL BE DIFFICULT TO TIME. BEST BET FOR STORMS IN THAT PERIOD WOULD BE FROM LATE AFTERNOON INTO THE OVERNIGHT HOURS. HIGHS FROM TUESDAY INTO FRIDAY SHOULD BE MOSTLY 80S AND LOWER 90S... WITH LOWS IN THE 60S TO LOWER 70S. MILLER && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
743 PM EDT SUN JUN 9 2013 .SYNOPSIS... FAIRLY QUIET WEATHER IS EXPECTED THIS EVENING WITH THE NORTH COUNTRY UNDER WEAK HIGH PRESSURE. A SLOW- MOVING UPPER-LEVEL LOW WILL PRODUCE A PROLONGED RAINFALL EVENT BEGINNING MONDAY AFTERNOON THRU WEDNESDAY MORNING. OCCASIONAL SHOWERS WILL PERSIST INTO FRIDAY BEFORE BECOMING DRIER BY THE WEEKEND. && .NEAR TERM /UNTIL 8 AM MONDAY MORNING/... AS OF 730 PM EDT SUNDAY...MINOR TWEAKS TO T/TD/MIN TEMP DATA AS WE HEAD INTO THE EVENING AND OVERNIGHT HOURS. RELATIVELY UNNOTICEABLE CHANGES AT PRIMARY FORECAST POINTS...BUT MORE NOTEWORTHY ACROSS THE HIGHER TERRAIN WHERE LATEST GFS BIAS-CORRECTED DATA CONTINUES TO STRUGGLE WITH AIRMASS REGIME CHANGE OVER THE PAST 24-HOURS. A BLEND OF MET/EKD BIAS-CORECTED DATA APPEARS MORE REASONABLE AND HAVE LEANED IN THIS DIRECTION ACCORDINGLY WHICH ALLOWS AREAS ABOVE 1500 FEET TO RADIATE OUT A TAD MORESO THAN PRIOR INDICATIONS. STILL LOOKING AT SOME PATCHY FOG HERE AND THERE...BUT NOT CONVINCED OF ANY WIDESPREAD BR/FG GIVEN RAP HYDROLAPSE DATA AND THE FACT THAT AT LEAST SOME HIGH CLOUDS WILL BE FILTERING INTO THE AREA LATER TONIGHT. THUS HAVE TWEAKED AREAL COVERAGE SLIGHTLY BASED OFF EXPECTED TD DEPRESSIONS AND WIND THRESHOLDS IN THE 05-09Z TIME RANGE RATHER THAN HIGHLIGHTING STRICTLY IN OUR CLIMO- FAVORED AREAS. AGAIN...ALL OF THESE ADJUSTMENTS FAIRLY MINOR WITH THE BULK OF THE INHERITED FORECAST REMAINING IN EXCELLENT SHAPE. HAVE A GREAT EVENING. PRIOR DISCUSSION FOLLOWS... WEAK SFC RIDGE IS CURRENTLY MOVING INTO THE NORTH COUNTRY THIS AFTERNOON WITH SKIES CLEARING FROM WEST TO EAST. CONTINUED CLEARING IS EXPECTED THROUGH THE FIRST HALF OF THE EVENING AS MID- LEVEL HEIGHTS BUILD. LIGHT NEAR-SFC WINDS AND SUBSIDENCE ALOFT SHOULD FAVORS DEVELOPMENT OF PATCHY FOG IN THE USUAL FOG-PRONE AREAS THIS EVENING. MID-/UPPER-LEVEL MOISTURE ADVECTION ALLOWS FOR INCREASING HIGH CLOUDS BY THE PRE- DAWN HOURS WITH CLOUDS CONTINUING TO LOWER AND THICKEN BY MORNING. LOW TEMPERATURES ARE BASED MOST CLOSELY AROUND THE MET MOS GUIDANCE WHICH PAINTS LOWS IN THE MID/UPPER 40S TO THE LOWER/MID 50S. && .SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... AS OF 334 PM EDT SUNDAY...THE MAIN WEATHER FEATURE IN THE PERIOD IS THE LARGE UPPER-LEVEL LOW MOVING IN FROM THE OHIO VALLEY AND GREAT LAKES REGION. ASSOCIATED LOW-LEVEL WARM AND MOISTURE ADVECTION REGIME AHEAD OF THE UPPER CYCLONE WILL PROMOTE INCREASING CLOUDS THROUGH THE DAY. PRECIPITATION TIMING STILL LOOKS ON TRACK FROM THE INHERITED FORECAST WITH AN INCREASING COVERAGE OF SHOWERS MONDAY AFTERNOON INTO MONDAY EVENING EVENTUALLY BECOMING A STEADY RAIN. WHILE INSTABILITY INDICES ARE ON THE LOW SIDE THINK THERE WILL BE ENOUGH UPPER FORCING TO SUPPORT AREAS OF EMBEDDED THUNDER MONDAY INTO MONDAY NIGHT. BY TUESDAY THE UPPER LOW MOVES OVERHEAD. WHILE WIDESPREAD SHOWERS ARE EXPECTED THROUGH TUESDAY....I HAVEN`T INCLUDED MENTION OF THUNDER ON TUESDAY AS WEAKENING DYNAMIC FORCING COMBINED WITH MEAGER INSTABILITY PARAMETERS SHOULD LIMIT THE THREAT. THE SYSTEM WILL BE A RATHER LONG-DURATION RAINFALL EVENT. THE HEAVIEST RAINFALL WILL TAKE PLACE MONDAY NIGHT INTO EARLY ON TUESDAY. REGARDING QPF...I DO EXPECT THERE TO BE SOME PRECIPITATION ENHANCEMENT ALONG THE FAVORED EAST-FACING SLOPE AREAS GIVEN THE SOUTHEASTERLY MEAN FLOW AND MOISTURE TRANSPORT. QPF AMOUNTS THEMSELVES ARE BASICALLY A BLEND OF THE LATEST SREF...GFS...AND ECMWF QPF AMOUNTS. AMOUNTS THROUGH 12Z WEDNESDAY RANGE FROM AN INCH IN THE SHADOWED CHAMPLAIN AND SAINT LAWRENCE VALLEYS TO AN INCH AND A HALF ALONG AFOREMENTIONED EAST- FACING SLOPE AREAS. GIVEN THE WET SOILS THERE MAY BE SOME MINOR NUISANCE HYDRO CONCERNS THAT WILL NEED TO BE WATCHED CLOSELY BUT REALLY NOT MUCH MORE THAN THAT AS THE RAIN IS FALLING ACROSS A LONGER PERIOD OF TIME. I WILL WORD ACCORDINGLY IN THE HWO PRODUCT HOWEVER. THE POTENTIAL ALSO MAY EXIST FOR SOME GUSTY SOUTHEAST WINDS TO TAKE PLACE ALONG SOME OF THE RIDGETOPS ON MONDAY NIGHT. BTV4 AND BTV12 EACH SHOW A SOUTHEASTERLY 925-850MB JET OF 35 TO 45 KTS ORIENTED ROUGHLY ALONG THE GREEN MOUNTAIN SPINE. NOT EXPECTING A DOWNSLOPE WIND EVENT AS LAPSE RATES ARE ROUGHLY NEAR NEUTRAL...BUT I DO HAVE GUSTS UP TO 30 MPH MENTIONED ALONG OUR EAST-FACING SLOPE AREAS FOR MONDAY NIGHT. HIGHS ON MONDAY SHOULD REACH INTO THE MID/UPPER 70S...THOUGH MORE IN THE WAY OF CLOUDS AND SHOWERS WILL LOWER HIGHS INTO THE UPPER 60S/LOWER 70S ON TUESDAY. LOWS ARE SIMILAR FOR MONDAY AND TUESDAY NIGHT...GENERALLY IN THE MID/UPPER 50S TO LOWER 60S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 320 PM EDT SUNDAY...FOR WEDNESDAY AND WED NGT...MDLS CONTINUE TO SLOWLY MV UPPER LOW EASTWARD INTO THE CANADIAN MARITIMES. THIS WILL ALLOW WK SFC RIDGE TO BUILD OVER THE CWA BRIEFLY DURING THE DAY THURSDAY. UPPER TROUGH ON FRIDAY WILL GIVE WAY TO HIGH PRESSURE FOR THE UPCOMING WEEKEND FROM CENTRAL CANADA/GREAT LKS REGION. RIDGE INTACT FOR LATE IN UPCOMING WEEKEND...BUT MDLS DO HINT AT FRNT/SFC LOW APPROACHING FROM THE WEST. PRECIPITATION IN THE EXTENDED WILL CONTINUE TO SHOW WRAPAROUND -RW FOR NORTHERN PORTIONS OF THE REGION AS NNW WINDS BRING MOISTURE ON BACKSIDE OF EXITING SYSTEM. HIGHEST POPS WILL CONTINUE TO BE FOR NE VT(LIKELY DO TO ITS PROXIMITY OF EXITING LOW) AND HIR ELEV OF DACKS(HIGH CHANCE)...TAPERING OFF TO THE NE KINGDOM BY EARLY THURSDAY MORNING. NEXT ROUND OF SHOWERS WILL OCCUR FRI/FRI NGT AS TROUGH SWINGS SOUTH. KEEPING CHANCE POPS IN FOR NOW DO TO AMT OF QPF BIAS IN LATEST ECMWF/GFS MDL RUNS W/ EMPHASIS IN HIR TRRN. FOR LATE IN WEEKEND WILL JUST PUT IN SL CHANCE FOR POSSIBLE SHOWER ALONG N NY BORDER. TEMPS IN EXTENDED STILL DEPENDENT ON CLD COVER FROM ABV MENTIONED SYSTEMS. HAVE MAINLY LOWERED POTENTIAL MAX TEMPS ON RAINY DAYS WHILE KEEPING OVERNGT LOWS CLOSE TO GUIDANCE. FOR SAT/SUN...EXPECTING NEAR NORMAL TEMPS W/ HIGHS IN THE 70S/U60S IN HIR ELEV. OVERNGT LOWS IN L50S/40S IN HIR ELEV FROM RADIATIONAL COOLING EFFECTS. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... THROUGH 00Z TUESDAY...PRIMARILY VFR EXPECTED THROUGH THE PERIOD...HOWEVER A PERIOD OF MVFR/IFR POSSIBLE AT MPV/SLK IN FOG/BR OVERNIGHT. SKIES WILL CLEAR THIS EVENING AS DIURNAL CUMULUS CLOUDS DISSIPATE. WILL SEE AN INCREASE IN HIGH CLOUDS AFTER 06Z TONIGHT AND CONTINUING INTO MONDAY MORNING. THESE CLOUDS COMBINED WITH SOME SUN-INDUCED DRYING DURING THE DAY WILL LIMIT THE EXTENT OF RADIATIONAL FOG. HOWEVER THE RECENT RAINFALL AND LIGHT WINDS WILL STILL CREATE CONDITIONS FAVORABLE FOR SOME FOG/BR DEVELOPMENT AT MPV/SLK WHERE TEMPERATURES APPROACH OR FALL BELOW THEIR CROSS- OVER TEMPERATURES. OTHERWISE CLOUDS CONTINUE INCREASE ON MONDAY WITH RAIN SHOWERS DEVELOPING AND INCREASING IN COVERAGE FROM SOUTHWEST TO NORTHEAST IN THE AFTERNOON AND EVENING...ESPECIALLY SLK/RUT. CONDITIONS SHOULD REMAIN MAINLY VFR THROUGH THE DAY. LIGHT AND VARIABLE WINDS TONIGHT TURN GENERALLY SOUTHERLY 5-10 KNOTS ON MONDAY...EXCEPT MSS WHERE SOME E/NE CHANNELED FLOW DEVELOPS. OUTLOOK 00Z TUESDAY THROUGH FRIDAY... 00Z TUESDAY THROUGH 00Z FRIDAY...VFR WITH REDUCTIONS TO MVFR/IFR LIKELY IN NUMEROUS SHOWERS AND POSSIBLE THUNDERSTORMS WITH A SERIES OF UPPER LEVEL DISTURBANCES. 00Z FRIDAY ONWARD...PRIMARILY VFR WITH HIGH PRESSURE BUILDING IN. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...LOCONTO NEAR TERM...JMG/LOCONTO SHORT TERM...LOCONTO LONG TERM...JN AVIATION...MUCCILLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
730 PM EDT SUN JUN 9 2013 .SYNOPSIS... FAIRLY QUIET WEATHER IS EXPECTED THIS EVENING WITH THE NORTH COUNTRY UNDER WEAK HIGH PRESSURE. A SLOW- MOVING UPPER-LEVEL LOW WILL PRODUCE A PROLONGED RAINFALL EVENT BEGINNING MONDAY AFTERNOON THRU WEDNESDAY MORNING. OCCASIONAL SHOWERS WILL PERSIST INTO FRIDAY BEFORE BECOMING DRIER BY THE WEEKEND. && .NEAR TERM /UNTIL 8 AM MONDAY MORNING/... AS OF 730 PM EDT SUNDAY...MINOR TWEAKS TO T/TD/MIN TEMP DATA AS WE HEAD INTO THE EVENING AND OVERNIGHT HOURS. RELATIVELY UNNOTICEABLE CHANGES AT PRIMARY FORECAST POINTS...BUT MORE NOTEWORTHY ACROSS THE HIGHER TERRAIN WHERE LATEST GFS BIAS-CORRECTED DATA CONTINUES TO STRUGGLE WITH AIRMASS REGIME CHANGE OVER THE PAST 24-HOURS. A BLEND OF MET/EKD BIAS-CORECTED DATA APPEARS MORE REASONABLE AND HAVE LEANED IN THIS DIRECTION ACCORDINGLY WHICH ALLOWS AREAS ABOVE 1500 FEET TO RADIATE OUT A TAD MORESO THAN PRIOR INDICATIONS. STILL LOOKING AT SOME PATCHY FOG HERE AND THERE...BUT NOT CONVINCED OF ANY WIDESPREAD BR/FG GIVEN RAP HYDROLAPSE DATA AND THE FACT THAT AT LEAST SOME HIGH CLOUDS WILL BE FILTERING INTO THE AREA LATER TONIGHT. THUS HAVE TWEAKED AREAL COVERAGE SLIGHTLY BASED OFF EXPECTED TD DEPRESSIONS AND WIND THRESHOLDS IN THE 05-09Z TIME RANGE RATHER THAN HIGHLIGHTING STRICTLY IN OUR CLIMO- FAVORED AREAS. AGAIN...ALL OF THESE ADJUSTMENTS FAIRLY MINOR WITH THE BULK OF THE INHERITED FORECAST REMAINING IN EXCELLENT SHAPE. HAVE A GREAT EVENING. PRIOR DISCUSSION FOLLOWS... WEAK SFC RIDGE IS CURRENTLY MOVING INTO THE NORTH COUNTRY THIS AFTERNOON WITH SKIES CLEARING FROM WEST TO EAST. CONTINUED CLEARING IS EXPECTED THROUGH THE FIRST HALF OF THE EVENING AS MID- LEVEL HEIGHTS BUILD. LIGHT NEAR-SFC WINDS AND SUBSIDENCE ALOFT SHOULD FAVORS DEVELOPMENT OF PATCHY FOG IN THE USUAL FOG-PRONE AREAS THIS EVENING. MID-/UPPER-LEVEL MOISTURE ADVECTION ALLOWS FOR INCREASING HIGH CLOUDS BY THE PRE- DAWN HOURS WITH CLOUDS CONTINUING TO LOWER AND THICKEN BY MORNING. LOW TEMPERATURES ARE BASED MOST CLOSELY AROUND THE MET MOS GUIDANCE WHICH PAINTS LOWS IN THE MID/UPPER 40S TO THE LOWER/MID 50S. && .SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... AS OF 334 PM EDT SUNDAY...THE MAIN WEATHER FEATURE IN THE PERIOD IS THE LARGE UPPER-LEVEL LOW MOVING IN FROM THE OHIO VALLEY AND GREAT LAKES REGION. ASSOCIATED LOW-LEVEL WARM AND MOISTURE ADVECTION REGIME AHEAD OF THE UPPER CYCLONE WILL PROMOTE INCREASING CLOUDS THROUGH THE DAY. PRECIPITATION TIMING STILL LOOKS ON TRACK FROM THE INHERITED FORECAST WITH AN INCREASING COVERAGE OF SHOWERS MONDAY AFTERNOON INTO MONDAY EVENING EVENTUALLY BECOMING A STEADY RAIN. WHILE INSTABILITY INDICES ARE ON THE LOW SIDE THINK THERE WILL BE ENOUGH UPPER FORCING TO SUPPORT AREAS OF EMBEDDED THUNDER MONDAY INTO MONDAY NIGHT. BY TUESDAY THE UPPER LOW MOVES OVERHEAD. WHILE WIDESPREAD SHOWERS ARE EXPECTED THROUGH TUESDAY....I HAVEN`T INCLUDED MENTION OF THUNDER ON TUESDAY AS WEAKENING DYNAMIC FORCING COMBINED WITH MEAGER INSTABILITY PARAMETERS SHOULD LIMIT THE THREAT. THE SYSTEM WILL BE A RATHER LONG-DURATION RAINFALL EVENT. THE HEAVIEST RAINFALL WILL TAKE PLACE MONDAY NIGHT INTO EARLY ON TUESDAY. REGARDING QPF...I DO EXPECT THERE TO BE SOME PRECIPITATION ENHANCEMENT ALONG THE FAVORED EAST-FACING SLOPE AREAS GIVEN THE SOUTHEASTERLY MEAN FLOW AND MOISTURE TRANSPORT. QPF AMOUNTS THEMSELVES ARE BASICALLY A BLEND OF THE LATEST SREF...GFS...AND ECMWF QPF AMOUNTS. AMOUNTS THROUGH 12Z WEDNESDAY RANGE FROM AN INCH IN THE SHADOWED CHAMPLAIN AND SAINT LAWRENCE VALLEYS TO AN INCH AND A HALF ALONG AFOREMENTIONED EAST- FACING SLOPE AREAS. GIVEN THE WET SOILS THERE MAY BE SOME MINOR NUISANCE HYDRO CONCERNS THAT WILL NEED TO BE WATCHED CLOSELY BUT REALLY NOT MUCH MORE THAN THAT AS THE RAIN IS FALLING ACROSS A LONGER PERIOD OF TIME. I WILL WORD ACCORDINGLY IN THE HWO PRODUCT HOWEVER. THE POTENTIAL ALSO MAY EXIST FOR SOME GUSTY SOUTHEAST WINDS TO TAKE PLACE ALONG SOME OF THE RIDGETOPS ON MONDAY NIGHT. BTV4 AND BTV12 EACH SHOW A SOUTHEASTERLY 925-850MB JET OF 35 TO 45 KTS ORIENTED ROUGHLY ALONG THE GREEN MOUNTAIN SPINE. NOT EXPECTING A DOWNSLOPE WIND EVENT AS LAPSE RATES ARE ROUGHLY NEAR NEUTRAL...BUT I DO HAVE GUSTS UP TO 30 MPH MENTIONED ALONG OUR EAST-FACING SLOPE AREAS FOR MONDAY NIGHT. HIGHS ON MONDAY SHOULD REACH INTO THE MID/UPPER 70S...THOUGH MORE IN THE WAY OF CLOUDS AND SHOWERS WILL LOWER HIGHS INTO THE UPPER 60S/LOWER 70S ON TUESDAY. LOWS ARE SIMILAR FOR MONDAY AND TUESDAY NIGHT...GENERALLY IN THE MID/UPPER 50S TO LOWER 60S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 320 PM EDT SUNDAY...FOR WEDNESDAY AND WED NGT...MDLS CONTINUE TO SLOWLY MV UPPER LOW EASTWARD INTO THE CANADIAN MARITIMES. THIS WILL ALLOW WK SFC RIDGE TO BUILD OVER THE CWA BRIEFLY DURING THE DAY THURSDAY. UPPER TROUGH ON FRIDAY WILL GIVE WAY TO HIGH PRESSURE FOR THE UPCOMING WEEKEND FROM CENTRAL CANADA/GREAT LKS REGION. RIDGE INTACT FOR LATE IN UPCOMING WEEKEND...BUT MDLS DO HINT AT FRNT/SFC LOW APPROACHING FROM THE WEST. PRECIPITATION IN THE EXTENDED WILL CONTINUE TO SHOW WRAPAROUND -RW FOR NORTHERN PORTIONS OF THE REGION AS NNW WINDS BRING MOISTURE ON BACKSIDE OF EXITING SYSTEM. HIGHEST POPS WILL CONTINUE TO BE FOR NE VT(LIKELY DO TO ITS PROXIMITY OF EXITING LOW) AND HIR ELEV OF DACKS(HIGH CHANCE)...TAPERING OFF TO THE NE KINGDOM BY EARLY THURSDAY MORNING. NEXT ROUND OF SHOWERS WILL OCCUR FRI/FRI NGT AS TROUGH SWINGS SOUTH. KEEPING CHANCE POPS IN FOR NOW DO TO AMT OF QPF BIAS IN LATEST ECMWF/GFS MDL RUNS W/ EMPHASIS IN HIR TRRN. FOR LATE IN WEEKEND WILL JUST PUT IN SL CHANCE FOR POSSIBLE SHOWER ALONG N NY BORDER. TEMPS IN EXTENDED STILL DEPENDENT ON CLD COVER FROM ABV MENTIONED SYSTEMS. HAVE MAINLY LOWERED POTENTIAL MAX TEMPS ON RAINY DAYS WHILE KEEPING OVERNGT LOWS CLOSE TO GUIDANCE. FOR SAT/SUN...EXPECTING NEAR NORMAL TEMPS W/ HIGHS IN THE 70S/U60S IN HIR ELEV. OVERNGT LOWS IN L50S/40S IN HIR ELEV FROM RADIATIONAL COOLING EFFECTS. && .AVIATION /23Z SUNDAY THROUGH FRIDAY/... THROUGH 18Z MONDAY...THRU 00Z MONDAY...SCT030-040 TRENDING TO SKC THEN BY 12Z MONDAY VFR COND CONTINUE WITH SCT040-080 INCR FROM THE SW AS NEXT WX SYSTEM APPROACHES. W/ SKC OVERNGT...MPV/SLK WILL SEE MIX OF MVFR/IFR COND FROM 05Z-12Z MONDAY W/ FG DOWN TO 1SM AND CIG BKN-OVC010. WINDS WNW 5-10KTS BECM LGT/VAR BY 00Z MON...THEN MAINLY SSE 5-10KTS BY 10Z-12Z. MSS WILL SEE ENE WINDS 5-10KTS SET UP BY 10Z MON. OUTLOOK 18Z MONDAY THROUGH FRIDAY... 18Z MONDAY THROUGH FRIDAY...VFR WITH REDUCTIONS TO MVFR/IFR LIKELY IN NUMEROUS SHOWERS AND POSSIBLE THUNDERSTORMS WITH NEXT LOW PRESSURE SYSTEM. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...LOCONTO NEAR TERM...JMG/LOCONTO SHORT TERM...LOCONTO LONG TERM...JN AVIATION...RJS/JN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
124 AM EDT SAT JUN 8 2013 .SYNOPSIS... PERIODS OF RAIN, MODERATE TO HEAVY AT TIMES, CAN BE EXPECTED THROUGH EARLY SATURDAY, ESPECIALLY IN THE POCONOS AND CATSKILLS. A FEW LINGERING SHOWERS ARE POSSIBLE SATURDAY BEFORE DRIER AIR BUILDS IN FOR SUNDAY. A LARGE STORM WITH MORE RAIN WILL COME IN FROM THE WEST MONDAY TO WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 11 PM UPDATE... +RA IS BRUSHING FAR ERN PIKE/SULLIVAN/DELAWARE CNTYS ATTM. RADAR MOSAICS/SAT TRENDS SUGGEST THIS SHOULD BE FAIRLY SHORT-LIVED...WITH RAINFALL TAPERING OFF AFTER 04-07Z. FLOOD WATCH WILL STILL BE RETAINED FOR THE TIME BEING. OTHWS...PATCHY -RA/DZ SHOULD PREVAIL OVERNIGHT. AGN...JUST MINOR TEMP/DEW PT TWEAKS WERE MADE. PREV DISC... 7 PM UPDATE... THE REMNANTS OF ANDREA WERE CENTERED OVER SE VA EARLY THIS EVE...WITH A CONTINUED STEADY NEWD HEADING EXPECTED OVERNIGHT. THE WRN FRINGES OF THE STEADY RAIN HAVE HAD TROUBLE MAKING MUCH PROGRESS TWDS THE NW DURG THE LATE AFTN/EARLY EVE HRS. AS PER THE LATEST HRRR GUIDANCE...WHICH HAS HANDLED THE OVERALL EVOLUTION OF ANDREA QUITE WELL THE LAST 6-12 HRS...THE WRN EDGE OF THE MAIN PCPN SHIELD SHOULD MAKE A BIT OF AN INLAND PUSH MORE TWDS A TOWANDA-BINGHAMTON-ONEONTA LN BY 02-03Z. HOWEVER...BY LTR TNT...AS ANDREA TRACKS TWDS THE NJ/SRN LONG ISLAND SHORE AREAS...AND CONTINUES TO BECOME MORE BAROCLINIC IN NATURE...THE PCPN SHIELD SHOULD PIVOT...AND START TO PUSH EWD OUT OF THE FA. BOTTOM LN...OUTSIDE OF CAT POPS FOR STEADY RAIN IN OUR ERN ZNS...WE`RE SIMPLY GOING TO CALL IT LGT RAIN OR DRIZZLE...BASED ON RECENT OBSERVATIONAL TRENDS...AND HI-RES NWP GUIDANCE. IT STILL APPEARS THAT THE LEADING EDGE OF THE +RA WILL EITHER BYPASS OUR CWA TO THE E...OR JUST SCRAPE ERN PIKE/SULLIVAN CNTYS FOR A BRIEF TIME LTR TNT. UNTIL WE SEE CLEAR EVIDENCE...HOWEVER...THAT OUR ERN CNTYS ARE COMPLETELY OUT OF THE WOODS...WE`LL MAINTAIN THE FLOOD WATCH. TEMPS/DEW PTS WERE JUST TWEAKED SLIGHTLY THIS EVE. EARLIER DISC... 4 PM UPDATE... FLOOD WATCH CONTINUES FOR PIKE SULLIVAN DELAWARE THROUGH TONIGHT. STILL LOOKS LIKE A CLOSE CALL WITH THE TROPICAL PRECIP COMING IN NOW AND LASTING INTO EARLY MORNING. QPF OF 1 TO 2 INCHES BUT OUR FURTHEST SE COULD GET 3 OR 4 INCHES IN EXTREME SE SULLIVAN AND PIKE. IF THESE AMOUNTS HOLD HEADWATER RIVER FORECAST POINTS WILL REMAIN WITHIN THEIR BANKS. IN THE LAST 24 HOURS MOSTLY LESS THAN HALF AN INCH IN THE WATCH AREA AND A LITTLE TO THE NW OF THAT. HEAVIER AMOUNTS OVER THE PA NJ BORDER BUT MOST OF THAT GONE AND NOT MUCH YET TODAY. IN THE SE PWATS OF 1.5 INCHES WILL GIVE RAINFALL RATES WHICH WILL INCREASE TO HALF AN INCH AN HOUR FOR SHORT PERIODS AROUND MIDNIGHT. STEADY RAIN WILL PROBABLY MOVE TO A ELM SYR LINE BUT MOST OF CENT NY WILL GET LESS THAN HALF AN INCH. TRACK OF ANDREA RIGHT ALONG THE COAST SO WIND WILL NOT BE A FACTOR IN THE CWA. ANDREA WILL HELP BRINGING ATLANTIC MOISTURE IN AHEAD OF IT. THE LIFT WITH IT AT LOW LEVELS AND IN THE RIGHT ENTRANCE REGION OF STRONG UL JET MEANS DEEP LIFT. ANDREA MOVES OUT INTO WRN NEW ENGLAND BETWEEN MIDNIGHT AND 4 AM SO RAIN WILL END BY SUNRISE. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/... 4 PM UPDATE... SLOW IMPROVEMENT WITH A WEAK UPPER LEVEL TROF MOVG THROUGH LATE SATURDAY. A FEW SHOWERS POSSIBLE DURING THE DAY ESPECIALLY THE AFTN WITH A LITTLE HEATING. A WEAK SFC HIGH PRESSURE MOVES IN SAT NGT THEN UPPER LEVEL RIDGING TAKES PLACE SUNDAY. WITH WEAK LOW LEVEL WIND FIELDS WILL BE TOUGH TO COMPLETELY CLEAR OUT. SOME SUN WILL PUSH TEMPS TO A70 SAT THEN 75 TO 80 SUNDAY. A SE LOW LEVEL FLOW SETS UP LATE SUNDAY AND CONTINUES INTO MONDAY AHEAD OF A WARM FRONT. THIS FRONT IS SLOW MOVING SO ONLY A CHC OF SHOWERS SUN NGT INTO MON MORN. THE WARM FRONT GETS HERE ON MONDAY WITH A STRONG TEMP AND MOISTURE GRADIENT. THE FRONT AHEAD OF A STACKED LOW PRESSURE SYSTEM SLOWLY MOVING EAST OUT OF THE PLAINS INTO THE MIDWEST. THUNDERSTORMS POSSIBLE MONDAY. SOME CLEARING AND LARGE LOW LEVEL INSTABILITY POSSIBLE IN NE PA AND MAYBE CENT NY DURING THE AFTN AND EVE. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... 300 PM UPDATE... STILL FAIRLY BUSY IN THE LONG TERM...WITH TROUGHY PATTERN ONLY GRADUALLY LETTING GO IN FAVOR OF ATTEMPTED RIDING TOWARDS THE NEXT WEEKEND. GIVEN THE WET PATTERN OF LATE...CONTINUED RAIN CHANCES AT LEAST EARLY IN THE LONG TERM MAY POSE WATER ISSUES FOR THE MOST SENSITIVE AREAS. SOME UNCERTAINTY TO SPECIFICS OF UPPER LOW AND/OR TROUGH PLACEMENTS...BUT THERE IS AGREEMENT THAT ON TUESDAY SOME SORT OF ADDITIONAL UPPER TROUGH SHOULD BE SWINGING THROUGH. AS WELL AS CONTINUED LIKELIHOOD OF SHOWERS...I ADDED A CHANCE OF THUNDER AS WELL BUT THIS WILL DEPEND ON IF INSTABILITY CAN BE MANAGED. GFS SUGGESTS FAIRLY POTENT NEGATIVELY TILTING UPPER TROUGH WHICH COULD ALLOW THUNDER. UPPER LOW CONSOLIDATES IN CENTRAL ONTARIO/SOUTHERN QUEBEC WEDNESDAY...WITH UNCERTAIN AMOUNT OF SYNOPTIC MOISTURE BROADLY AROUND IT /MORE SO IN GFS/. ISOLATED TO SCATTERED SHOWERS FIGURED FOR WEDNESDAY AT THIS TIME. BY THURSDAY...MODELS AGREE ON UPPER LOW DEPARTING BUT DISAGREE ON IF FLOW REMAINS CYCLONIC IN ITS WAKE...YET EITHER WAY MOISTURE IS QUITE LIMITED SO I ONLY HAVE SLIGHT CHANCE OF SHOWERS. SURFACE HIGH PRESSURE TRIES TO TAKE CHARGE INTO FRIDAY...WITH AT LEAST FLAT RIDGING IF NOT OUTRIGHT UPPER RIDGING NOSING IN FROM THE GREAT LAKES. UNCERTAIN IF THERE WILL BE EMBEDDED WAVES WITHIN THAT FLOW...BUT OVERALL VERY LIMITED MOISTURE AND SURFACE HIGH WOULD SUGGEST ONLY SLIGHT CHANCE POPS AT BEST FRIDAY...THUS I OPTED LOWER THAN WPC GUIDANCE. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... PLENTY OF MOISTURE ARND AS THE REMAINS OF TS ANDREA ZIP UP THE CST. THIS WILL CONT THE SPOTTY IFR AND MVFR CIGS AND VSBYS INTO SAT. WEAK HIPRES AND SLOW DRYING ARRIVES SAT AFTN AND WILL CONT THE SLOW IMPRVMT OF CONDS WITH VFR LIKELY AFT 18Z AND CONTG THRU THE END OF THE PD. LGT WINDS THIS MRNG WILL BECOME WLY ON SAT BUT LESS THAN 10 KTS WITH THE WEK GRADIENT ASSOCIATED WITH THE SFC HI. OUTLOOK... SAT NGT-SUN...MAINLY VFR EXCEPT IFR VALLEY FOG POSSIBLE...MAINLY KELM PREDAWN HRS SUN MRNG. SUN NGT THRU TUE...MVFR AND LOCALIZED IFR IN SHOWERS AND POSSIBLE THUNDERSTORMS AROUND SLOW MOVING LOW PRESSURE SYSTEM. WED...MAINLY VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH UNTIL NOON EDT TODAY FOR PAZ048. NY...FLOOD WATCH UNTIL NOON EDT TODAY FOR NYZ057-062. && $$ SYNOPSIS...TAC NEAR TERM...MLJ/TAC SHORT TERM...TAC LONG TERM...MDP AVIATION...CMG/DGM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
941 PM EDT SUN JUN 9 2013 .SYNOPSIS... SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN ARE EXPECTED THROUGH TUESDAY AHEAD OF A COLD FRONT. ABOVE NORMAL TEMPERATURES WILL PREVAIL MID WEEK. A COLD FRONT WILL APPROACH LATE IN THE WEEK WITH DRY AND RELATIVELY COOL HIGH PRESSURE ANTICIPATED NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AS OF 940 PM SUNDAY...TROPICAL MOISTURE CONTINUES TO POP SCATTERED DELUGES ACROSS OUR N AND NE ZONES THIS MID-EVENING. A FLOOD WARNING REMAINS EFFECTIVE FOR A CONFINED AREA OF PENDER COUNTY EAST OF THE COMMUNITY OF CURRIE...WHERE THE INTERSECTION OF HIGHWAY 421 AND HIGHWAY 210 HAS EXPERIENCED SEVERAL INCHES OF STANDING WATER. THE ROAD IS NOT CLOSED BUT TROOPERS ARE SLOWING APPROACHING NIGHT-TIME COMMUTERS. RADAR TRENDS SUGGEST A BRIEF BREAK INTO LATE EVENING BUT TEAMING ECHOS OFFSHORE SOUTH THROUGH SOUTHEAST OF CAPE FEAR MAY BRING ADDITIONAL HEAVY RAINS FOR THE OVERNIGHT PERIOD. WILL MAINTAIN HIGHEST POP VALUES NEAR THE COAST GENERALLY NORTH OF MURRELLS INLET THROUGH THE NEAR TERM PERIOD...AND ALSO ACROSS THE FAR WEST INTERIOR WHERE ACTIVITY OVER CENTRAL SC APPEARS POISED TO CLIP DARLINGTON AND MARLBORO COUNTIES INTO THE LATE EVENING. ELEVATED DEWPOINTS AND TROPICAL MOISTURE OVER THE AREA WILL KEEP MIN TEMPS IN THE MIDDLE 70S MOST AREAS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...A POTENT MID-LEVEL TROUGH WILL APPROACH THE FORECAST AREA ON MON AND THEN MOVE E OF THE AREA DURING TUE. DEEP SW FLOW WILL TAP MOISTURE FROM THE GULF OF MEXICO AND BRING IT N ACROSS THE CAROLINAS. PRECIPITABLE WATER VALUES WILL PEAK OVER 2 INCHES ON MON. A SHORTWAVE TROUGH...EMBEDDED IN SW FLOW...WILL MOVE ACROSS THE AREA DURING MON. WILL CONTINUE TO FORECAST LIKELY TO CATEGORICAL POPS FOR MON. ALTHOUGH STORM MOTIONS WILL NOT BE PARTICULARLY SLOW...SHOWERS AND THUNDERSTORMS MAY TRAIN OVER THE SAME AREA...LEADING TO PONDING IN LOW-LYING OR POOR DRAINAGE AREAS. WILL INCLUDE MENTION OF HEAVY RAIN ON MON. THICK CLOUD COVER SHOULD HELP TO LIMIT THE MAGNITUDE OF INSTABILITY. HOWEVER...MIXED LAYER CAPE VALUES SHOULD STILL REACH 500 TO 700 J/KG. GIVEN MID-LEVEL LAPSE RATES WILL BE POOR...SEVERE WEATHER IS VERY UNLIKELY. THE MAIN RISK WILL BE VERY HEAVY RAINFALL WHICH WILL FALL ON ALREADY WET SOILS FROM RECENT HEAVY RAIN EVENTS. CONVECTION SHOULD TRANSITION FROM THE LAND TO THE CLIMATOLOGICALLY FAVORED WATER DURING MON NIGHT AND SO WILL TREND POPS HIGHER OVER THE WATER AND LOWER OVER LAND DURING THE NIGHT. HOWEVER...SOME OF THIS CONVECTION MAY BLEED ONTO THE COAST...ESPECIALLY AS A WEAK DISTURBANCE ALOFT RACES UP THE COAST. THE AIRMASS WILL BE TRENDING DRIER ON TUE AS THE TROUGH AXIS SWINGS THROUGH. HOWEVER...INSTABILITY WILL BE MUCH HIGHER AS DRIER AIR... ESPECIALLY IN THE MID-LEVELS...ALLOWS FOR SIGNIFICANT BREAKS OF SUNSHINE. A DEVELOPING WESTERLY FLOW ALOFT SHOULD TEND TO LIMIT THE AMOUNT OF CONVECTION...FIRST ACROSS INLAND AREAS AND THEN ALONG THE COAST LATER IN THE DAY. THEREFORE...WILL SHOW POPS TRENDING LOWER THROUGH THE DAY...HIGHEST AT THE COAST. INSTABILITY WILL BE MUCH HIGHER ON TUE...WITH MIXED LAYER CAPE VALUES BETWEEN 1500 AND 2000 J/KG. HOWEVER...MID LEVEL LAPSE RATES SHOULD BE UNIMPRESSIVE. CAN NOT RULE OUT A WET MICROBURST ON TUE...BUT ANY SEVERE WEATHER IS EXPECTED TO BE ISOLATED. A SLOW MOVING SURFACE COLD FRONT WILL FINALLY REACH THE AREA LATE TUE NIGHT. MODELS SHOW THIS FRONT GETTING HUNG UP AS IT BUMPS THE BERMUDA RIDGE. IF THE FRONT DOES BRIEFLY REACH OR PUSH THROUGH THE EASTERN CAROLINAS...IT WILL QUICKLY BECOME ILL-DEFINED AND WASH OUT WITH MUCH WARMER TEMPERATURES EXPECTED FOR WED. CLOUDS AND CONVECTION SHOULD HELP HOLD TEMPS TO THE LOWER TO MID 80S ON MON. TUE...SIGNIFICANT BREAKS OF DEVELOPING SUNSHINE SHOULD ALLOW TEMPS TO REACH WELL UP INTO THE 80S. SOME INLAND AREAS COULD HIT 90 DEGREES WHILE A SW RESULTANT KEEPS COASTAL BRUNSWICK AND SOUTHERN NEW HANOVER COUNTIES IN THE LOWER 80S. OVERNIGHT LOWS WILL GENERALLY BE AROUND 70 DEGREES TO MID 70S VERY NEAR THE COAST. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 3 PM SUNDAY...AREA WILL BE ON THE NE FRINGE OF UPPER LEVEL RIDGE WHILE PIEDMONT TROUGH DEVELOPS AT THE SURFACE. 850MB TEMPS WARM TO ABOUT 21C ALLOWING MOST PLACES TO WARM INTO THE 90S. THE UPPER RIDGE RETROGRADES ON THURSDAY ALLOWING FOR A DECENT SHORTWAVE TO PASS BY JUST TO THE NORTH. WE MAY BE ON THE SOUTHERN FRINGE OF CLUSTERS OF THUNDERSTORMS BUT THE MID LEVEL DRYING MAY BE HARD TO OVERCOME. COLD FRONT GETS PUSHED THROUGH THURSDAY NIGHT BRINGING BEST RAINFALL CHANCES EVEN IF OVERALL QPF PROSPECTS MARGINALIZED BY APPRECIABLE MOISTURE INFLUX AHEAD OF THE FROPA. NORTHWEST FLOW ALOFT OVER THE WEEKEND AND A WEAK SURFACE PRESSURE PATTERN SHOULD ALLOW FOR FAIRLY SEASONABLE TEMPERATURES. THERE MAY BE JUST ENOUGH LOW LEVEL MOISTURE FOR VERY ISOLATED DIURNAL CONVECTION. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... AS OF 01Z...THE SHOWER ACTIVITY INLAND IS BEGINNING TO WIND DOWN AS MAINLY VFR CONDITIONS SHOULD PREVAIL EARLY THIS EVENING. THE MOIST AIRMASS IN PLACE OVER OUR AREA SHOULD ALLOW FOG/STRATUS TO DEVELOP AGAIN OVERNIGHT. EXPECT IFR CIGS/VSBYS INLAND AND MVFR CIGS ALONG THE COAST AFTER 06Z. THE HRRR INDICATES SOME SHOWERS DEVELOPING OFFSHORE WILL IMPACT THE COASTAL TERMS OVERNIGHT...SO HAVE INCLUDED TEMPO -SHRA FOR KMYR/KCRE/KILM EARLY MONDAY. SHOWERS AND T-STORMS ARE LIKELY AT ALL TERMS DURING THE DAY ON MONDAY AS A SHORTWAVE MOVES OVER THE AREA AHEAD OF AN UPPER TROUGH APPROACHING THE CAROLINAS. EXPECT MVFR/LOW VFR CIGS TO PREVAIL THRU THE AFTN HOURS WITH TEMPO IFR POSSIBLE IN HEAVIER SHOWERS AND T-STORMS. S/SW WINDS WILL STRENGTHEN DURING THE DAY... BECOMING 10-15 KTS WITH GUSTS OF 20 KTS IN THE AFTN. EXTENDED OUTLOOK...SHOWERS/T-STORMS WITH PERIODS OF MVFR/IFR THROUGH TUESDAY. CHANCE OF SHOWERS THURSDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 940 PM SUNDAY...SOUTH TO SOUTHEAST FLOW WILL INCREASE A LITTLE OVERNIGHT AS A COLD FRONT APPROACHES FROM THE NORTHWEST. SPEEDS ARE NOT EXPECTED TO EXCEED 15 KT BEFORE THE END OF THE PERIOD BUT WINDS MAY VEER TO SOUTH-SOUTHWEST AS THE PERIOD ENDS. SEAS WILL RUN 2 TO 4 FT MAINLY IN S WAVES WITH INTERVALS OF 5-6 SECONDS...AND WEAKER LONGER PERIOD SE WAVES IN THE MIX. SHOWERS WITH ISOLATED TSTMS SHOULD BE EXPECTED ON THE WATERS FOR THE OVERNIGHT PERIOD WITH A THREAT OF CLOUD TO WATER STRIKES. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...SOUTH WINDS WILL INCREASE DURING MONDAY AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF A POTENT TROUGH. A NOCTURNAL JET WILL BRING STRONGER WINDS MONDAY NIGHT. THE WIND DIRECTION WILL VEER MORE TO THE SW MON NIGHT WITH SW WINDS CONTINUING THROUGH THE REMAINDER OF THE PERIOD. THE STRONGEST WINDS ARE EXPECTED TUE AND TUE EVE...AND SPEEDS COULD REACH AROUND 20 KT. SEAS WILL BUILD THROUGH THE PERIOD AND THE PROSPECTS FOR SIX FOOT SEAS ARE INCREASING FOR LATE MON INTO TUE NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED DURING THE PERIOD WITH THE GREATEST COVERAGE LIKELY TO OCCUR DURING THE LATE NIGHT AND MORNING HOURS PRIOR TO MIDDAY. HEAVY RAIN WILL BRING POOR VISIBILITIES. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 3 PM SUNDAY...SOUTHWESTERLY WIND WAVES COMBINED WITH SOME SOUTHEASTERLY SWELL ENERGY ON WEDNESDAY TO POSSIBLY YIELD SOME SCEC-WORTHY 5 FT SEAS MAINLY OVER NRN ZONES. STRENGTHENING PIEDMONT TROUGH ON THURSDAY TO TIGHTEN THE GRADIENT JUST ENOUGH FOR POSSIBLE LOW END ADVISORY. THE APPROACH OF A COLD FRONT WILL ALSO BOLSTER THIS EFFECT. THIS FRONT PUSHES ACROSS THE WATERS BRINGING A SHARP VEER LATE THURSDAY NIGHT. NORTHERLY SUBSIDING WINDS AND SEAS EXPECTED POST FROPA ON FRIDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MJC/III SHORT TERM...RJD LONG TERM...MBB AVIATION...BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
747 PM EDT SUN JUN 9 2013 .SYNOPSIS... SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN ARE EXPECTED EARLY IN THE WORK WEEK AHEAD OF A COLD FRONT WHICH WILL BRIEFLY REACH THE AREA LATE TUESDAY NIGHT BEFORE DISSIPATING. WEAK HIGH PRESSURE WILL BRING ABOVE NORMAL TEMPERATURES MID-WEEK. ANOTHER COLD FRONT WILL APPROACH LATE IN THE WEEK. DRIER AND RELATIVELY COOLER HIGH PRESSURE WILL BUILD IN BEHIND FRONT FOR NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AS OF 3 PM SUNDAY...LINGERING ALTO CU HAS LIMITED TEMPERATURE RISE THUS FAR. DESPITE ABUNDANT DEEP MOISTURE...PRECIPITABLE WATER VALUES ARE APPROACHING 2 INCHES...SO FAR LITTLE IN THE WAY OF CONVECTION HAS BEEN ABLE TO DEVELOP. FARTHER SOUTH AND WEST AREAS WITH LITTLE CLOUD THIS MORNING HAVE DEVELOPED GOOD COVERAGE OF STORMS. STILL THINK CONVECTION WILL DEVELOP WITHIN THE ILM AREA BUT WHAT DEVELOPS IS NOT LIKELY TO BE AS STRONG AS THE STORMS TO THE SOUTH AND WEST. EXCEPTION MAY BE ACROSS DARLINGTON AND MARLBORO COUNTIES WHERE CLOUD COVER HAS BEEN LIMITED AND TEMPS HAVE RISEN INTO THE UPPER 80S. STORMS THAT DO DEVELOP ARE LIKELY TO CONTAIN HEAVY RAIN. DEEP WARM CLOUD LAYER AND STORM MOTIONS UNDER 10 KT COMBINED WITH PREVIOUSLY MENTIONED DEEP MOISTURE WILL LEAD TO HIGH PRECIPITATION RATES. STORM DEVELOPMENT SHOULD BE LIMITED TO THE AFTERNOON AND EARLY EVENING HOURS BEFORE AIR MASS BECOMES MORE STABLE AND ACTIVITY WANES. ONCE AGAIN GUIDANCE IS SHOWING DEVELOPMENT OF SHOWERS OVER THE COASTAL WATERS LATE IN THE PERIOD. INCREASING CONVERGENCE AHEAD OF ADVANCING COLD FRONT AND DEEP MOISTURE ALONG WITH DIVERGENT FLOW ALOFT AND WEAK PVA MAKE A COMPELLING CASE FOR COASTAL SHOWERS AND ISOLATED THUNDERSTORMS AS THE PERIOD ENDS. GIVEN THE LIMITED COVERAGE THIS MORNING WILL CAP POP AT CHC...HIGHEST AT THE COAST. CLOUD COVER AND LOW LEVEL MOISTURE ALONG WITH INCREASING SOUTHERLY FLOW WILL KEEP LOWS IN THE LOW TO MID 70S. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...A POTENT MID-LEVEL TROUGH WILL APPROACH THE FORECAST AREA ON MON AND THEN MOVE E OF THE AREA DURING TUE. DEEP SW FLOW WILL TAP MOISTURE FROM THE GULF OF MEXICO AND BRING IT N ACROSS THE CAROLINAS. PRECIPITABLE WATER VALUES WILL PEAK OVER 2 INCHES ON MON. A SHORTWAVE TROUGH...EMBEDDED IN SW FLOW...WILL MOVE ACROSS THE AREA DURING MON. WILL CONTINUE TO FORECAST LIKELY TO CATEGORICAL POPS FOR MON. ALTHOUGH STORM MOTIONS WILL NOT BE PARTICULARLY SLOW...SHOWERS AND THUNDERSTORMS MAY TRAIN OVER THE SAME AREA...LEADING TO PONDING IN LOW-LYING OR POOR DRAINAGE AREAS. WILL INCLUDE MENTION OF HEAVY RAIN ON MON. THICK CLOUD COVER SHOULD HELP TO LIMIT THE MAGNITUDE OF INSTABILITY. HOWEVER...MIXED LAYER CAPE VALUES SHOULD STILL REACH 500 TO 700 J/KG. GIVEN MID-LEVEL LAPSE RATES WILL BE POOR...SEVERE WEATHER IS VERY UNLIKELY. THE MAIN RISK WILL BE VERY HEAVY RAINFALL WHICH WILL FALL ON ALREADY WET SOILS FROM RECENT HEAVY RAIN EVENTS. CONVECTION SHOULD TRANSITION FROM THE LAND TO THE CLIMATOLOGICALLY FAVORED WATER DURING MON NIGHT AND SO WILL TREND POPS HIGHER OVER THE WATER AND LOWER OVER LAND DURING THE NIGHT. HOWEVER...SOME OF THIS CONVECTION MAY BLEED ONTO THE COAST...ESPECIALLY AS A WEAK DISTURBANCE ALOFT RACES UP THE COAST. THE AIRMASS WILL BE TRENDING DRIER ON TUE AS THE TROUGH AXIS SWINGS THROUGH. HOWEVER...INSTABILITY WILL BE MUCH HIGHER AS DRIER AIR... ESPECIALLY IN THE MID-LEVELS...ALLOWS FOR SIGNIFICANT BREAKS OF SUNSHINE. A DEVELOPING WESTERLY FLOW ALOFT SHOULD TEND TO LIMIT THE AMOUNT OF CONVECTION...FIRST ACROSS INLAND AREAS AND THEN ALONG THE COAST LATER IN THE DAY. THEREFORE...WILL SHOW POPS TRENDING LOWER THROUGH THE DAY...HIGHEST AT THE COAST. INSTABILITY WILL BE MUCH HIGHER ON TUE...WITH MIXED LAYER CAPE VALUES BETWEEN 1500 AND 2000 J/KG. HOWEVER...MID LEVEL LAPSE RATES SHOULD BE UNIMPRESSIVE. CAN NOT RULE OUT A WET MICROBURST ON TUE...BUT ANY SEVERE WEATHER IS EXPECTED TO BE ISOLATED. A SLOW MOVING SURFACE COLD FRONT WILL FINALLY REACH THE AREA LATE TUE NIGHT. MODELS SHOW THIS FRONT GETTING HUNG UP AS IT BUMPS THE BERMUDA RIDGE. IF THE FRONT DOES BRIEFLY REACH OR PUSH THROUGH THE EASTERN CAROLINAS...IT WILL QUICKLY BECOME ILL-DEFINED AND WASH OUT WITH MUCH WARMER TEMPERATURES EXPECTED FOR WED. CLOUDS AND CONVECTION SHOULD HELP HOLD TEMPS TO THE LOWER TO MID 80S ON MON. TUE...SIGNIFICANT BREAKS OF DEVELOPING SUNSHINE SHOULD ALLOW TEMPS TO REACH WELL UP INTO THE 80S. SOME INLAND AREAS COULD HIT 90 DEGREES WHILE A SW RESULTANT KEEPS COASTAL BRUNSWICK AND SOUTHERN NEW HANOVER COUNTIES IN THE LOWER 80S. OVERNIGHT LOWS WILL GENERALLY BE AROUND 70 DEGREES TO MID 70S VERY NEAR THE COAST. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 3 PM SUNDAY...AREA WILL BE ON THE NE FRINGE OF UPPER LEVEL RIDGE WHILE PIEDMONT TROUGH DEVELOPS AT THE SURFACE. 850MB TEMPS WARM TO ABOUT 21C ALLOWING MOST PLACES TO WARM INTO THE 90S. THE UPPER RIDGE RETROGRADES ON THURSDAY ALLOWING FOR A DECENT SHORTWAVE TO PASS BY JUST TO THE NORTH. WE MAY BE ON THE SOUTHERN FRINGE OF CLUSTERS OF THUNDERSTORMS BUT THE MID LEVEL DRYING MAY BE HARD TO OVERCOME. COLD FRONT GETS PUSHED THROUGH THURSDAY NIGHT BRINGING BEST RAINFALL CHANCES EVEN IF OVERALL QPF PROSPECTS MARGINALIZED BY APPRECIABLE MOISTURE INFLUX AHEAD OF THE FROPA. NORTHWEST FLOW ALOFT OVER THE WEEKEND AND A WEAK SURFACE PRESSURE PATTERN SHOULD ALLOW FOR FAIRLY SEASONABLE TEMPERATURES. THERE MAY BE JUST ENOUGH LOW LEVEL MOISTURE FOR VERY ISOLATED DIURNAL CONVECTION. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... AS OF 00Z...THE SHOWER ACTIVITY INLAND IS BEGINNING TO WIND DOWN AS MAINLY VFR CONDITIONS SHOULD PREVAIL EARLY THIS EVENING. THE MOIST AIRMASS IN PLACE OVER OUR AREA SHOULD ALLOW FOG/STRATUS TO DEVELOP AGAIN OVERNIGHT. EXPECT IFR CIGS/VSBYS INLAND AND MVFR CIGS ALONG THE COAST AFTER 06Z. THE HRRR INDICATES SOME SHOWERS DEVELOPING OFFSHORE WILL IMPACT THE COASTAL TERMS OVERNIGHT...SO HAVE INCLUDED TEMPO -SHRA FOR KMYR/KCRE/KILM EARLY MONDAY. SHOWERS AND T-STORMS ARE LIKELY AT ALL TERMS DURING THE DAY ON MONDAY AS A SHORTWAVE MOVES OVER THE AREA AHEAD OF AN UPPER TROUGH APPROACHING THE CAROLINAS. EXPECT MVFR/LOW VFR CIGS TO PREVAIL THRU THE AFTN HOURS WITH TEMPO IFR POSSIBLE IN HEAVIER SHOWERS AND T-STORMS. S/SW WINDS WILL STRENGTHEN DURING THE DAY... BECOMING 10-15 KTS WITH GUSTS OF 20 KTS IN THE AFTN. EXTENDED OUTLOOK...SHOWERS/T-STORMS WITH PERIODS OF MVFR/IFR THROUGH TUESDAY. CHANCE OF SHOWERS THURSDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM SUNDAY...SOUTH TO SOUTHEAST FLOW THIS AFTERNOON WILL INCREASE A LITTLE OVERNIGHT AS COLD FRONT APPROACHES FROM THE NORTHWEST. SPEEDS ARE NOT EXPECTED TO EXCEED 15 KT BEFORE THE END OF THE PERIOD BUT WINDS MAY VEER TO SOUTH-SOUTHWEST AS THE PERIOD ENDS. SEAS WILL RUN 2 TO 4 FT MAINLY AS SOUTHERLY SWELL WITH VERY LITTLE SOUTHEAST WIND WAVE. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...SOUTH WINDS WILL INCREASE DURING MONDAY AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF A POTENT TROUGH. A NOCTURNAL JET WILL BRING STRONGER WINDS MONDAY NIGHT. THE WIND DIRECTION WILL VEER MORE TO THE SW MON NIGHT WITH SW WINDS CONTINUING THROUGH THE REMAINDER OF THE PERIOD. THE STRONGEST WINDS ARE EXPECTED TUE AND TUE EVE...AND SPEEDS COULD REACH AROUND 20 KT. SEAS WILL BUILD THROUGH THE PERIOD AND THE PROSPECTS FOR SIX FOOT SEAS ARE INCREASING FOR LATE MON INTO TUE NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED DURING THE PERIOD WITH THE GREATEST COVERAGE LIKELY TO OCCUR DURING THE LATE NIGHT AND MORNING HOURS PRIOR TO MIDDAY. HEAVY RAIN WILL BRING POOR VISIBILITIES. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 3 PM SUNDAY...SOUTHWESTERLY WIND WAVES COMBINED WITH SOME SOUTHEASTERLY SWELL ENERGY ON WEDNESDAY TO POSSIBLY YIELD SOME SCEC-WORTHY 5 FT SEAS MAINLY OVER NRN ZONES. STRENGTHENING PIEDMONT TROUGH ON THURSDAY TO TIGHTEN THE GRADIENT JUST ENOUGH FOR POSSIBLE LOW END ADVISORY. THE APPROACH OF A COLD FRONT WILL ALSO BOLSTER THIS EFFECT. THIS FRONT PUSHES ACROSS THE WATERS BRINGING A SHARP VEER LATE THURSDAY NIGHT. NORTHERLY SUBSIDING WINDS AND SEAS EXPECTED POST FROPA ON FRIDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...III SHORT TERM...RJD LONG TERM...MBB AVIATION...BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
151 AM EDT SAT JUN 8 2013 .SYNOPSIS... POST-TROPICAL STORM ANDREA WILL MOVE ACROSS EASTERN VIRGINIA OVERNIGHT AND OFFSHORE SATURDAY. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO EARLY NEXT WEEK AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES RIDE ACROSS THE AREA IN SOUTHWEST FLOW. A COLD FRONT WILL APPROACH FROM THE NORTHWEST EARLY NEXT WEEK AND MAY BRIEFLY MOVE THROUGH THE AREA ON WEDNESDAY...BEFORE RETREATING BACK TO THE NORTH. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1:45 AM SATURDAY...THUNDERSTORM ACTIVITY FROM EARLIER THIS EVENING HAS MOVED NORTHEAST ACROSS THE FORECAST AREA AND WILL SHORTLY EXIT ROBESON COUNTY. LIGHT SHOWER ACTIVITY IS APPROACHING FORECAST AREA FROM THE SW AND SHOULD MOVE ACROSS LATER THIS MORNING. HAVE UPDATED FORECAST ACCORDINGLY. PREVIOUS DISCUSSION FROM 7:30 PM FOLLOWS BELOW: NOW THAT ANDREA IS OUT OF OUR HAIR...ATTENTION IS TURNING UPSTREAM TO AN IMPRESSIVE LITTLE VORT MAX OVER THE SOUTHERN APPALACHIANS THAT IS HELPING SUPPORT QUITE A FEW THUNDERSTORMS FROM EASTERN GEORGIA INTO WESTERN NORTH CAROLINA. WHILE ALL MODELS SHOW THE HEART OF THIS DISTURBANCE PASSING WELL NORTHWEST OF THE EASTERN CAROLINAS OVERNIGHT...AN ASSOCIATED 200/300 MB JET STREAK WILL ENHANCE LIFT EVEN ACROSS THE COASTAL AREAS AFTER MIDNIGHT WITH INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS. THERMALLY...LAPSE RATES ARE ACTUALLY STEEPER THAN THE MOIST ADIABATIC RATE OVERNIGHT WHICH COULD BE SUPPORTIVE OF DEEP CONVECTION GIVEN SUFFICIENT LOW-LEVEL MOISTURE. SURFACE-BASED INSTABILITY SHOULD BECOME CAPPED OFF DUE TO A COOLING BOUNDARY LAYER...BUT MODEL SOUNDINGS SUGGEST PARCELS LIFTED FROM 950 MB WOULD ONLY HAVE TO OVERCOME A SMALL NEGATIVE REGION TO RELEASE 500-1000 J/KG OF CAPE. LINEAR EXTRAPOLATION OF CURRENT THUNDERSTORM ACTIVITY JUST EAST OF AUGUSTA GA SHOWS IT COULD BE MOVING INTO FLORENCE AND WILLIAMSBURG COUNTIES SHORTLY AFTER 11 PM. ADDITIONAL CONVECTION WEST AND SOUTHWEST OF CHARLOTTE COULD MOVE INTO THE PEE DEE REGION NORTH OF FLORENCE BY 11 PM. THE LATEST FEW HRRR RUNS SHOW THE BEST POTENTIAL COVERAGE OF STORMS ALONG THE I-95 CORRIDOR IN THE 11PM TO 2 AM TIME FRAME. LESSER COVERAGE IS INDICATED AS THE CONVECTION MOVES EAST TOWARD THE CAPE FEAR COAST AFTER 2 AM. UPDATES TO THE FORECAST HAVE FOCUSED ON THIS DEVELOPING CONVECTIVE POTENTIAL. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... AS OF 3 PM FRIDAY...THE SOUTHERN PERIPHERY OF A MID-LEVEL SHORTWAVE TROUGH WILL MOVE ACROSS THE AREA ON SAT. THE ENVIRONMENT WILL STILL BE MOIST WITH PRECIPITABLE WATER VALUES TO START THE DAY IN EXCESS OF ONE AND A HALF INCHES. HOWEVER...SIGNIFICANT DRYING IS EXPECTED ABOVE 10 KFT DURING THE AFTERNOON. GIVEN INCREASING INSTABILITY AND THE MODEST UPPER LEVEL SUPPORT...WILL INCLUDE SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE DAY. DIURNAL CONVECTION SHOULD WANE DURING THE EVE AS THE AIRMASS STABILIZES. CONVECTION SHOULD DEVELOP ACROSS THE WATERS DURING THE NIGHT AND MAY SKIM PORTIONS OF THE IMMEDIATE COAST LATE AT NIGHT. DEEP SOUTHWEST FLOW REMAINS ACROSS THE AREA ON SUNDAY AND PRECIPITABLE WATER VALUES ACTUALLY INCREASE AGAIN. MODEL SOUNDINGS SHOW A WEAK CAP HANGING ON THROUGH THE DAY AND THIS MAY SERVE TO SUPPRESS CONVECTION. THE SEABREEZE AND PIEDMONT TROUGH SHOULD ACT TO FOCUS/CONVERGE/LIFT MOISTURE BOTH DAYS...ESPECIALLY SUNDAY...AND SO THERE MAY BE A HIGHER CONCENTRATION OF SHOWERS AND THUNDERSTORMS ON THE BOUNDARY ON THAT DAY. STORM MOTIONS SHOULD BE HIGH ENOUGH TO LARGELY PRECLUDE ANY ADDITIONAL FLOODING...ALTHOUGH THE GROUND WILL REMAIN NEARLY SATURATED ACROSS MUCH OF THE AREA THIS WEEKEND. HOWEVER...RIVER LEVELS WILL CONTINUE TO RISE AND SEVERAL WILL APPROACH FLOOD STAGE. AT THIS TIME...A FLOOD WARNING IS IN EFFECT FOR PORTIONS OF THE CAPE FEAR RIVER AROUND WILLIAM O HUSKE. TEMPS WILL BE TYPICAL FOR THIS TIME OF YEAR WITH HIGHS IN THE MID AND UPPER 80S WITH PERHAPS A 90 DEGREE READING WELL INLAND... ESPECIALLY ON SUNDAY. LOWS WILL BE AROUND 70 WITH LOWER TO PERHAPS MID 70S AT THE BEACHES. DEWPOINTS WILL REMAIN HIGH THROUGH THE PERIOD...AND SO IT WILL FEEL HUMID. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF NOON FRIDAY...AN UPPER LEVEL SHORTWAVE TROUGH IS JUST TO THE WEST OF THE REGION ON MONDAY AND THIS TROUGH WILL SLOWLY MOVE TO THE COAST BY EARLY WEDNESDAY BEFORE DAMPENING OUT. THE REGION WILL BE IN WEST-NORTHWESTERLY FLOW ALOFT AND A SMALLER SHORTWAVE FLOW WILL APPROACH THE REGION LATE THURSDAY. AT THE SURFACE...A COLD FRONT WILL APPROACH THE REGION LATE MONDAY INTO TUESDAY. WITH THE SECOND TROUGH MENTIONED ABOVE WILL BE ASSOCIATED WITH A SECOND SURFACE COLD FRONT THAT WILL APPROACH THE REGION LATE THURSDAY. BEST PRECIPITATION CHANCES WILL BE MONDAY INTO TUESDAY AND AGAIN LATE THURSDAY. MAXIMUM TEMPERATURES ARE EXPECTED TO RANGE FROM THE MIDDLE 80S TO NEAR 90 AND LOWS WILL RANGE FROM UPPER 60S TO LOWER 70S. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 06Z...KLBT MAY BE IMPACTED BY INLAND SHOWER ACTIVITY AT THE VERY START OF THE TAF PERIOD...WHERE TEMPO MVFR CONDITIONS ARE POSSIBLE. ANY PCPN SHOULD HELP FURTHER SATURATE THE NEAR SFC LAYER...AND SO MVFR FOG APPEARS INCREASINGLY LIKELY FOR KLBT/KFLO BEFORE DAYBREAK. ALONG THE COAST...THE WINDS ARE EXPECTED TO REMAIN TOO STRONG FOR ANY FOG FORMATION. DURING THE DAY...VFR SHOULD PREVAIL WITH SC/BKN CU AROUND 3-4KFT. SOUTHWEST WINDS WILL INCREASE DURING THE DAYLIGHT HOURS WITH GUSTS UP TO 20 KTS ALONG THE COAST LATER THIS AFTN. THERE IS A SLIGHT CHANCE OF SHOWERS/T-STORMS TODAY...BUT COVERAGE WILL BE LIMITED. EXTENDED OUTLOOK...SCATTERED SHOWERS/T-STORMS WITH PERIODS OF SUB-VFR CONDITIONS POSSIBLE SUNDAY THROUGH TUESDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1:45 AM SATURDAY...WINDS AND SEAS ARE IN-LINE WITH PREVIOUS FORECASTS AND NO SIGNIFICANT CHANGES ARE NEEDED. PREVIOUS DISCUSSION FROM 7:30 PM FOLLOWS: POST-TROPICAL STORM ANDREA IS NOW WELL NORTH OF THE AREA AND HER EFFECTS WILL CONTINUE TO DIMINISH THROUGH THE NIGHT. A FAIRLY TIGHT PRESSURE GRADIENT SOUTH OF ANDREA WILL CONTINUE THROUGH THE NIGHT WITH SOUTHWEST WINDS DIMINISHING TO 15-20 KNOTS AWAY FROM SHORE OVERNIGHT. SEAS WILL TAKE SOME TIME TO DIMINISH...AND ARE STILL BEING MEASURED AT 13 FEET AT THE FRYING PAN SHOALS BUOY...AND 6-8 FEET AT THE NEARSHORE BUOY ARRAY NEAR CAPE FEAR. THE BIGGEST CHANGE TO THE MARINE FORECAST IS TO INCREASE FORECAST WAVE HEIGHTS NEARSHORE WHERE THE OCEAN CREST PIER WAVE GAUGE IS SHOWING 6 FT SEAS JUST OUTSIDE THE SURF ZONE...IMPLYING SUBSTANTIAL UPWARD REVISIONS OF UP TO +4 FEET ARE NEEDED TO THE MARINE FORECASTS WITHIN A FEW MILES OF SHORE. SHOWERS AND THUNDERSTORMS ARE BECOMING QUITE WIDESPREAD IN THE WESTERN CAROLINAS...AND IT IS POSSIBLE THIS ACTIVITY MAY SURVIVE ITS PASSAGE DOWN TO THE COAST. THE BEST POTENTIAL APPEARS TO BE NORTH OF MYRTLE BEACH AFTER 2 AM...WITH MOST LOCATIONS REMAINING DRY. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 PM FRIDAY...ROUGH SEAS WILL BE SUBSIDING THROUGH THE DAY SAT...BUT A PERIOD OF SMALL CRAFT ADVISORY FOR SEAS IS EXPECTED TO CONTINUE INTO THE DAY ON SAT. OTHERWISE CONDITIONS WILL BE BELOW SMALL CRAFT ADVISORY LEVELS THIS WEEKEND. SW WINDS SAT AND SAT NIGHT WILL BACK SLIGHTLY TO SSW SUN AND SUN NIGHT AS THE BUILDING WESTERN ATLANTIC RIDGE REORIENTS. WIND SPEEDS WILL BE 15 KT OR LESS THROUGH THE PERIOD. LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF NOON FRIDAY...SOUTHWEST WINDS WILL PREVAIL THROUGH TUESDAY AHEAD OF A COLD FRONT THAT WILL PUSH INTO THE COASTAL WATERS EARLY WEDNESDAY. SEAS ARE EXPECTED TO START FROM 3 TO 4 FEET WITH ISOLATED 5 FOOTERS NORTH OF CAPE FEAR. AS THE FRONTAL BOUND DRAWS NEAR TO THE MARINE WATERS A POSSIBLE SMALL CRAFT ADVISORY CONDITIONS WILL OCCUR NORTH OF CAPE FEAR LATE TUESDAY INTO EARLY WEDNESDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...HIGH RIP CURRENT RISK FROM 7 AM EDT THIS MORNING THROUGH THIS EVENING FOR NCZ106-108-110. MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR AMZ254- 256. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR AMZ250- 252. && $$ NEAR TERM...REK AVIATION...BJR MARINE...REK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1026 PM EDT SUN JUN 9 2013 .SYNOPSIS... A WARM FRONT WILL MOVE NORTH OF THE AREA TONIGHT. LOW PRESSURE WILL MOVE EAST ACROSS THE OHIO VALLEY FROM TONIGHT THROUGH MONDAY...WITH SHOWERS AND THUNDERSTORMS EXPECTED. HIGH PRESSURE WILL MOVE IN ON TUESDAY...BEFORE CHANCES FOR SHOWERS AND STORMS BEGIN AGAIN ON WEDNESDAY AND THURSDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... SCT SHRA ARE OCCURRING ACROSS THE FA ATTM. BETTER ORGANIZED CONVECTION INCLUDING TSRA IS SHOULD WORK INTO THE FA AFTER 06Z. ADJUSTED THE TIME OF THE HIGHEST POPS TO BETWEEN 06Z-12Z OVERNIGHT AND INCREASED THE CHC OF THUNDER SOME. KEPT THE HIGHEST POPS AT 80 FOR NOW. LEFT THE OVERNIGHT LOWS IN THE MID 60S. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... A LARGE AREA OF LOW PRESSURE AT THE MID LEVELS WILL MOVE ESE INTO THE OHIO VALLEY BY MONDAY MORNING. AHEAD OF THIS FEATURE...THERE WILL BE A SIGNIFICANT AMOUNT OF LIFT...WITH FALLING HEIGHTS AND AN INCREASING HEIGHT GRADIENT. THERE WILL ALSO BE SUPPORT ALOFT FROM DIVERGENCE EAST OF THE LOW CENTER. LOWER IN THE ATMOSPHERE...A SIGNIFICANT AMOUNT OF MOISTURE WILL BE ADVECTED INTO THE OHIO VALLEY...ON A 25-30 KNOT LLJ. A TROUGH EXTENDS SOUTH FROM THE LOW PRESSURE AREA...WITH A WELL-DEFINED WIND SHIFT AND SOME DEGREE (THOUGH NOT STRONG) OF COLDER/DRIER AIR BEHIND IT. THE FRONT WILL BE MOVING THROUGH THE CWA GENERALLY IN THE 12Z-18Z TIME FRAME. THIS WILL COMBINE WITH THE LLJ-FORCED ACTIVITY MOVING IN FROM THE SOUTH TO CREATE A WET MORNING ACROSS THE ILN CWA. POPS ARE CATEGORICAL THROUGH THE PERIOD AHEAD OF THE FRONT (04Z-14Z FROM W TO E). THE HIGH-RES MODELS DEPICT THE MODE AS MORE OF A WIDESPREAD SHOWERS TYPE OF EVENT (WITH EMBEDDED THUNDER)...AS OPPOSED TO AN EASILY-TRACKABLE WALL OF PRECIPITATION. POPS ARE BEING HELD AT 80 PERCENT FOR NOW...THOUGH 100 POPS WILL PROBABLY BE NECESSARY ONCE THE EXACT TIMING CAN BE DETERMINED. BEHIND THE FRONT...THE MID-LEVEL TROUGH AXIS WILL STILL BE WORKING ITS WAY EAST...NOT REALLY MAKING ITS WAY OUT OF THE CWA UNTIL AFTER 00Z. IF THERE WILL BE ANY THREAT FOR STRONG STORMS TOMORROW...IT WOULD BE MORE LIKELY WITH ADDITIONAL CONVECTIVE ACTIVITY IN THE AFTERNOON. UNDER THE TROUGH AXIS...TEMPS ALOFT WILL BE DECREASING QUITE A BIT. WHETHER OR NOT THERE WILL BE ANY BREAKS IN THE CLOUDS BEHIND THE FRONT REMAINS IN QUESTION...AS THERE WILL STILL BE A SIGNIFICANT AMOUNT OF LOW LEVEL MOISTURE. IT WOULD NOT TAKE A LOT OF SUN TO GENERATE ENOUGH WEAK INSTABILITY TO TAKE ADVANTAGE OF THE COLDER TEMPS ALOFT...AND PRODUCE SOME SMALL HAIL. HOWEVER...AT NO POINT DURING THE DAY DOES THE INSTABILITY APPEAR TO BE STRONG ENOUGH TO SUPPORT MORE THAN A LOW-END SEVERE THREAT. POPS ARE HIGHEST AHEAD OF THE COLD FRONT...BUT THEN REMAIN IN THE LIKELY AND HIGH CHANCE CATEGORIES THROUGH THE AFTERNOON (EARLY EVENING IN THE EAST). THE TEMP FORECAST IS GOING TO ASSUME DIURNAL CONDITIONS ON MONDAY...ALTHOUGH IN REALITY IT MAY NOT QUITE PLAY OUT THAT WAY...WITH THE FRONT CROSSING THE AREA AND OCCASIONAL PRECIPITATION EXPECTED. MAX TEMPS ARE CLOSER TO THE COOL MET GUIDANCE AND SIMILAR TO (OR SLIGHTLY LOWER THAN) THE PREVIOUS FORECAST. SOME OF THE RAW MODELS WERE EVEN LOWER ON TEMPS MONDAY. SKY GRIDS WERE RAISED A BIT ON MONDAY NIGHT...WITH RATHER THICK RH REMAINING IN PLACE THROUGH TUESDAY MORNING ON THE BACK SIDE OF THE TROUGH. && .LONG TERM /TUESDAY THROUGH SUNDAY/... MODELS ARE IN FAIRLY DECENT AGREEMENT IN TERMS OF SYNOPTIC SCALE FEATURES THROUGH THE IMMEDIATE LONG TERM...THEN THEY START TO DIFFER ON TIMING LATE IN THE PERIOD. THE UPPER LEVEL FLOW PATTERN WILL CONTINUE TO SHOW TROUGHS DOMINATING THE WRN AND ERN U.S. WITH RIDGING SPREAD OUT OVER THE SOUTHERN TO CENTRAL PLAINS TO THE MID-LOWER MS VALLEY. ON TUESDAY...UPR LVL LOW WILL DEPART TO THE EAST WHILE A WEAK SFC RIDGE BUILDS QUICKLY INTO THE REGION. A SHOWER MAY LINGER IN THE FAR EAST EARLY ON...OTHERWISE...SKIES WILL BECOME PARTLY TO MOSTLY SUNNY. THERE IS NOT A LOT OF CAA BEHIND DEPARTING SYSTEM SO TEMPERATURES SHOULD REBOUND INTO THE LOWER AND PERHAPS MID 80S NEAR THE TRI-STATE AREA. MODELS CONTINUE TO KEY ON A DISTINCT S/WV WHICH WILL ROUND THE PERIPHERY OF THE RIDGE IN THE NRN PLAINS AND WILL SUBSEQUENTLY DIVE SE INTO THE OHIO VALLEY REGION LATE WEDNESDAY NIGHT INTO THURSDAY. BEFORE THIS HAPPENS...RETURN FLOW AND A DEVELOPING LOW LEVEL JET WILL ALLOW A WARM FRONT TO PIVOT TOWARD THE REGION TUESDAY NIGHT. THIS MAY LEAD TO SOME SHOWER/THUNDERSTORM DEVELOPMENT AFTER MIDNIGHT. ON WEDNESDAY...WARM FRONT WILL NUDGE INTO OUR REGION WHILE A PSEUDO WEST TO EAST FRONTAL BOUNDARY DEVELOPS TO OUR NORTH. THESE FEATURES WILL SERVE AS A FOCUS FOR SHOWERS AND STORMS WEDNESDAY WITH THE GREATEST ACTIVITY/COVERAGE EXPECTED WEDNESDAY NIGHT INTO THURSDAY MORNING AS S/WV ENERGY INTERACTS WITH THE FRONTAL BOUNDARY/WEAK SFC WAVE AS THEY PUSH EAST/SOUTHEAST THROUGH THE REGION. IT CONTINUES TO APPEAR THAT THE ATMOSPHERE COULD BECOME RATHER UNSTABLE WEDNESDAY AFTERNOON AND NIGHT...WITH THUNDERSTORMS LIKELY CONGEALING INTO AN MCS WITH THE POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS. IN ADDITION...THE PARAMETERS ARE RIPE FOR HEAVY RAINFALL AS WELL WITH PWATS APPROACHING 2 INCHES AND WARM CLOUD DEPTH IN EXCESS OF 4 KM. THERE IS STILL SOME UNCERTAINTY THIS FAR OUT IN TIME BUT WILL CONTINUE TO MONITOR GUIDANCE TRENDS. WILL ALSO CONTINUE TO MENTION THESE HAZARDS IN THE EXTENDED HWO. HIGHS ON WEDNESDAY WILL BE CLOUD AND RAIN DEPENDENT RANGING FROM THE LOWER 80S NORTH TO NEAR 90 SOUTH. IT WILL ALSO BE QUITE HUMID. LOWS WEDNESDAY NIGHT WILL GENERALLY BE IN THE 60S WITH COOLER WEATHER ON TAP ON THURSDAY IN THE WAKE OF THE FRONT. PCPN ON THURSDAY SHOULD END FROM NW TO SE THROUGH THE DAY. FOR THURSDAY NIGHT INTO FRIDAY...HIGH PRESSURE WILL BUILD INTO OUR REGION. DRIER WEATHER AND NEAR SEASONAL TEMPERATURES ARE EXPECTED. THE HIGH WILL MOVE OFF TO THE EAST ON SATURDAY AS NW FLOW OVER THE REGION BRINGS PERHAPS AN EMBEDDED DISTURBANCE LATE IN THE DAY. WILL KEEP A LOW THREAT FOR SHOWERS/STORMS ACRS THE NW. FOR SATURDAY NIGHT AND SUNDAY...A MORE BONAFIDE COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST. TIMING IS AN ISSUE STILL THIS FAR OUT SO WILL KEEP POPS IN THE CHANCE CATEGORY AT THIS POINT. TEMPERATURES THIS WEEKEND SHOULD WARM TO NEAR OR SLIGHTLY ABOVE NORMAL READINGS. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... AREA OF SHRA LIFTING N THRU THE NRN TAFS IS BEING HANDLED PRETTY WELL BY THE HIGHER RESOLUTION MODELS. THEY TAKE THIS ACTIVITY N OF THE TAFS OVER THE NEXT FEW HOURS. TAFS WILL THEN BE IN A LULL FOR A FEW HOURS UNTIL THE CONVECTION OUT WEST WORKS IN AFT 04-06Z. THIS CONVECTION IS BEING DRIVEN BY THE DIGGING H5 LOW. EARLIER RUNS OF THE HRRR AND RAP SHOWED THE LULL THIS EVENING...THEN BROUGHT CONVECTION TO THE OH/IN BORDER BY 06Z...AND SWUNG IT INTO THE TAFS BETWEEN 06-12Z. WENT WITH A PERIOD OF TEMPO MVFR TSRA AT THE TAFS AS THESE STORMS WORK ACROSS THE TAFS. THE SFC LOW AND FRONT WORK ACROSS THE TAFS BETWEEN 12-16Z...PUSHING THE TSRA EWD. BROUGHT BACK A VCTS FOR LATE MORNING INTO AFTN AS MODELS DESTABILIZE THE ATMOSPHERE AND H5 LOW SWINGS ACROSS THE OH VALLEY. THE MONDAY AFTN CONVECTION SHOULD BE OF THE SCT NATURE. OUTLOOK...THUNDERSTORMS EXPECTED WEDNESDAY NIGHT INTO THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM...SITES SHORT TERM...HATZOS LONG TERM...HICKMAN AVIATION...SITES
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
916 PM EDT SUN JUN 9 2013 .SYNOPSIS... A WARM FRONT WILL MOVE NORTHWARD ACROSS OHIO AND NW PA TONIGHT. LOW PRESSURE WILL MOVE ACROSS THE EASTERN GREAT LAKES ON MONDAY. THE COLD FRONT ASSOCIATED WITH THIS LOW WILL THEN STALL OVER OHIO FOR THE MIDDLE OF THE WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... SHOWERS HAVE MADE IT INTO OUR SOUTHWESTERN COUNTIES THIS EVENING. LATEST HI-RES MODELS TRYING TO SHOW ONE ROUND OF SHOWERS/ISOLATED THUNDERSTORMS FOR THE REMAINDER OF THE EVENING INTO THE EARLY OVERNIGHT...POSSIBLY A PERIOD OF MORE SCATTERED SHOWER ACTIVITY...AND THEN ANOTHER ROUND OF MORE WIDESPREAD SHOWERS TOWARD DAWN MOVING INTO THE WEST. THIS SEEMS REASONABLE CONSIDERING THE CURRENT RADAR MOSAIC AND THE FACT THAT THE UPPER TROUGH WILL NEAR THE OHIO VALLEY/LOWER GREAT LAKES THROUGH THE COURSE OF THE NIGHT. HAVE EITHER A SLIGHT CHANCE OR CHANCE OF THUNDERSTORMS MENTIONED TONIGHT. TEMPERATURES SHOULD REMAIN FAIRLY WARM TONIGHT WITH THE INCREASED MOISTURE LEVELS AND THE CLOUD COVER. EXPECT TO SE LOWS IN THE 60S AT MOST LOCATIONS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... SHOWERS WILL CONTINUE MOST OF THE DAY ON MONDAY AS THE LOW MOVES ACROSS THE EASTERN GREAT LAKES. IT WILL BE SLOW TO TAPER OFF THE SCATTERED SHOWERS MONDAY EVENING. ADDITIONAL JET ENERGY MOVING THROUGH THE NW FLOW WILL LIKELY KEEP THE SCATTERED SHOWERS OVER EASTERN HALF OF THE REGION INTO TUESDAY. UNFORTUNATELY THE COLD FRONT WILL STALL OVER CENTRAL OHIO TUESDAY NIGHT INTO WEDNESDAY WITH ANOTHER RIPPLE OF LOW PRESSURE MOVING ALONG IT. THIS WILL BRING A RETURN OF SHOWERS BY WEDNESDAY MORNING. IT APPEARS THE CHANCES OF SHOWERS WILL INCREASE INTO WEDNESDAY AFTERNOON AND EVENING WITH THE HEAVIEST RAIN LIKELY ACROSS THE SOUTHERN HALF OF THE COUNTY WARNING AREA. WE WILL MONITOR THIS OVER THE NEXT COUPLE DAYS. SHOWERS AND THE ISOLATED THUNDER ON MONDAY WILL KEEP TEMPERATURES COOLER ON MONDAY BUT IT STILL LOOKS AS IF IT WILL REACH THE LOWER TO MID 70S. WARMER ON TUESDAY AND WEDNESDAY IF WE CAN GET SOME BREAKS WITH HIGHS IN THE MIDDLE AND UPPER 70S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AMPLIFICATION OF UPPER LEVEL RIDGE TAKES PLACE OVER THE CENTRAL UNITED STATES BY MID WEEK ALLOWING DIGGING TROUGH TO DIVE DOWN THE EAST COAST. UNFORTUNATELY...THIS DOES NOT FAVOR WELL FOR WARMER TEMPERATURES GOING INTO THE END OF THE WEEK. OUR SAVING GRACE WILL BE THE FACT THE UPPER LEVEL RIDGE MOVES FAIRLY QUICKLY EAST ALLOWING SURFACE HIGH TO PUSH EAST OF THE AREA BY SATURDAY. ONCE THIS TAKES PLACE...A RETURN TO WARM SOUTHERLY COMPONENT WINDS WILL DEVELOP ALLOWING FOR WARM AIR ADVECTION TO TAKE PLACE INTO THE WEEKEND. AS THE SURFACE HIGH PRESSURE BUILDS SOUTHEAST ACROSS THE AREA ON THURSDAY...THE PRECIPITATION THAT IS EXPECTED TO HANG AROUND FOR A GOOD PORTION OF THE FIRST HALF OF THE WEEK WILL FINALLY EXIT STAGE RIGHT. THIS WILL BRING FAIR WEATHER BACK TO THE FORECAST AREA INTO THE WEEKEND. HOWEVER...A FAST MOVING UPPER LEVEL POSITIVE VORTICITY MAXIMUM WILL RACE SOUTHEAST TOWARD THE AREA SATURDAY INTO SUNDAY. THIS FEATURE HAS LIMITED MOISTURE AND COULD BRING A MINIMAL CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY SATURDAY NIGHT INTO SUNDAY. NEARLY ZONAL FLOW DEVELOPS BY SUNDAY AND THIS SHOULD ALLEVIATE ANY STRONG SURGES OF COLD AIR INTO THE AREA FOR A SHORT PERIOD. BUT THIS WILL BE SHORT LIVED AS A RETURN TO AN AMPLIFIED RIDGE IN THE WEST AND TROUGH IN THE EAST WILL DEVELOP AFTER THE WEEKEND. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... RADAR SHOWS SHOWERS MOVING NORTH/NORTHEAST OUT OF SWRN OHIO THIS EVENING. CIGS WITH THIS REMAIN VFR WITH CIG HEIGHTS LOWERING TO ABOUT BKN-OVC050-060. EXPECT THIS TO MOVE INTO THE AREA IMPACTING KFDY AND KMFD FIRST BETWEEN 8 AND 9PM AND THEN CONTINUING TO SPREAD ACROSS THE AREA AS IT THINS. THE HRRR SHOWS THIS WELL...FOLLOWED BY SHOWERS AND POSSIBLY THUNDERSTORMS MOVING IN FROM THE WEST AFTER MIDNIGHT AS UPPER LOW PRESSURE APPROACHES THE AREA FROM THE WEST. AFTER 06Z THE NAM ALSO SHOWS DEEP MOISTURE FILLING IN ACROSS THE AREA. WILL BRING CIGS AND VISIBILITIES DOWN TO MVFR AFTER MIDNIGHT FROM THE WEST WITH IFR LIKELY AT TIMES LATE TONIGHT AND EARLY MONDAY MORNING IN LOW CIGS AND/OR RAIN/FOG/MIST. MOISTURE AND INSTABILITY IN PLACE MONDAY AFTERNOON SO WOULD EXPECT ADDITIONAL SHOWERS AND POSSIBLY THUNDERSTORMS TO AGAIN TAKE/SUSTAIN CONDITIONS TO NON VFR. .OUTLOOK...NON VFR CONDITIONS LIKELY MONDAY NIGHT IN SHRA/TSRA AND POSSIBLY AGAIN WEDNESDAY AFTERNOON INTO THURSDAY. && .MARINE... THE LAKE APPEARED IT WILL REMAIN RELATIVELY QUIET FOR THE MOST PART. THERE IS THE POSSIBILITY THAT WE COULD SEE SMALL CRAFT CONDITIONS DEVELOP FROM THE ISLANDS WEST LATE TONIGHT INTO MONDAY MORNING. HOWEVER...IT APPEARS THIS WILL BE VERY SHORT LIVED AS WINDS DIMINISH BY LATE MONDAY MORNING. ONCE WE GET PAST MONDAY MORNING...THE GRADIENT APPEARS THAT IT WILL NOT GET TO TIGHT THROUGH FRIDAY AND THIS SHOULD RESULT IN RELATIVELY CALM WINDS AND WAVES ON THE LAKE. THE PROBLEM WILL BE THE PRECIPITATION THREAT EXPECTED FROM TONIGHT THROUGH THURSDAY MORNING WITH IMPROVEMENT BY FRIDAY AS HIGH PRESSURE BUILDS INTO THE REGION. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...MULLEN NEAR TERM...MULLEN/OUDEMAN SHORT TERM...MULLEN LONG TERM...LOMBARDY AVIATION...TK MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
809 PM EDT SUN JUN 9 2013 .SYNOPSIS... A WARM FRONT WILL MOVE NORTH OF THE AREA TONIGHT. LOW PRESSURE WILL MOVE EAST ACROSS THE OHIO VALLEY FROM TONIGHT THROUGH MONDAY...WITH SHOWERS AND THUNDERSTORMS EXPECTED. HIGH PRESSURE WILL MOVE IN ON TUESDAY...BEFORE CHANCES FOR SHOWERS AND STORMS BEGIN AGAIN ON WEDNESDAY AND THURSDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AN AREA OF SHOWERS AND THUNDERSTORMS OVER KENTUCKY HAS BEEN ADVECTING ON A NNE TRAJECTORY...BUT LARGELY PROPAGATING MORE EASTWARD...THANKS TO THE DEARTH OF INSTABILITY OVER THE ILN CWA. BASED ON CURRENT CONDITIONS (OBSERVED AND VIA LAPS ANALYSIS) IT APPEARS THAT MODELS WERE SLIGHTLY TOO AGGRESSIVE IN BUILDING INSTABILITY IN THE SOUTHERN CWA...LARGELY DUE TO SOME SLIGHT OVERFORECASTING IN BOTH TEMPS AND DEWPOINTS. HOWEVER...THE THETA-E ADVECTION IS ON THE WAY...SIGNIFIED BY THE DEEP SOUTHERLY FLOW THROUGH THE LOWER LEVELS OF THE ATMOSPHERE...WITH INCREASING PWAT VALUES (FORECAST TO EXCEED 1.50" BY EVENING). WHILE RADAR TRENDS DO NOT APPEAR PARTICULARLY FAVORABLE FOR SEVERE WEATHER THIS AFTERNOON AND EVENING...SOME HEAVY RAIN WILL BE POSSIBLE. HOWEVER...THE MORE SIGNIFICANT RAINFALL LOOKS TO HOLD OFF UNTIL LATE IN THE OVERNIGHT AND INTO MONDAY MORNING. THE POPS WILL FOLLOW GUIDANCE FROM HRRR/RAP DEPICTIONS. THIS WILL START OFF VERY HIGH IN THE SOUTHERN CWA (CATEGORICAL) AND THEN DIMINISH SLIGHTLY (LIKELY) AS THE INITIAL BATCH OF FORCING MOVES NORTHWARD THROUGH THE AREA...GENERALLY THROUGH 06Z. ALTHOUGH SOME SHOWERS WILL BE POSSIBLE AFTER THIS BATCH...MOST OF THE MODELS INDICATE A LULL IN THE WIDESPREAD PRECIPITATION. NO SIGNIFICANT CHANGES WERE MADE TO THE TEMP/SKY FORECASTS OVERNIGHT...WITH RATHER MOIST AND INCREASINGLY CLOUDY CONDITIONS EXPECTED. THIS WILL KEEP TEMPS IN THE MID TO UPPER 60S ACROSS THE CWA. WINDS WILL BACK SLIGHTLY OVERNIGHT...AS THEY STAY UP IN THE 5-10 KNOT RANGE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... A LARGE AREA OF LOW PRESSURE AT THE MID LEVELS WILL MOVE ESE INTO THE OHIO VALLEY BY MONDAY MORNING. AHEAD OF THIS FEATURE...THERE WILL BE A SIGNIFICANT AMOUNT OF LIFT...WITH FALLING HEIGHTS AND AN INCREASING HEIGHT GRADIENT. THERE WILL ALSO BE SUPPORT ALOFT FROM DIVERGENCE EAST OF THE LOW CENTER. LOWER IN THE ATMOSPHERE...A SIGNIFICANT AMOUNT OF MOISTURE WILL BE ADVECTED INTO THE OHIO VALLEY...ON A 25-30 KNOT LLJ. A TROUGH EXTENDS SOUTH FROM THE LOW PRESSURE AREA...WITH A WELL-DEFINED WIND SHIFT AND SOME DEGREE (THOUGH NOT STRONG) OF COLDER/DRIER AIR BEHIND IT. THE FRONT WILL BE MOVING THROUGH THE CWA GENERALLY IN THE 12Z-18Z TIME FRAME. THIS WILL COMBINE WITH THE LLJ-FORCED ACTIVITY MOVING IN FROM THE SOUTH TO CREATE A WET MORNING ACROSS THE ILN CWA. POPS ARE CATEGORICAL THROUGH THE PERIOD AHEAD OF THE FRONT (04Z-14Z FROM W TO E). THE HIGH-RES MODELS DEPICT THE MODE AS MORE OF A WIDESPREAD SHOWERS TYPE OF EVENT (WITH EMBEDDED THUNDER)...AS OPPOSED TO AN EASILY-TRACKABLE WALL OF PRECIPITATION. POPS ARE BEING HELD AT 80 PERCENT FOR NOW...THOUGH 100 POPS WILL PROBABLY BE NECESSARY ONCE THE EXACT TIMING CAN BE DETERMINED. BEHIND THE FRONT...THE MID-LEVEL TROUGH AXIS WILL STILL BE WORKING ITS WAY EAST...NOT REALLY MAKING ITS WAY OUT OF THE CWA UNTIL AFTER 00Z. IF THERE WILL BE ANY THREAT FOR STRONG STORMS TOMORROW...IT WOULD BE MORE LIKELY WITH ADDITIONAL CONVECTIVE ACTIVITY IN THE AFTERNOON. UNDER THE TROUGH AXIS...TEMPS ALOFT WILL BE DECREASING QUITE A BIT. WHETHER OR NOT THERE WILL BE ANY BREAKS IN THE CLOUDS BEHIND THE FRONT REMAINS IN QUESTION...AS THERE WILL STILL BE A SIGNIFICANT AMOUNT OF LOW LEVEL MOISTURE. IT WOULD NOT TAKE A LOT OF SUN TO GENERATE ENOUGH WEAK INSTABILITY TO TAKE ADVANTAGE OF THE COLDER TEMPS ALOFT...AND PRODUCE SOME SMALL HAIL. HOWEVER...AT NO POINT DURING THE DAY DOES THE INSTABILITY APPEAR TO BE STRONG ENOUGH TO SUPPORT MORE THAN A LOW-END SEVERE THREAT. POPS ARE HIGHEST AHEAD OF THE COLD FRONT...BUT THEN REMAIN IN THE LIKELY AND HIGH CHANCE CATEGORIES THROUGH THE AFTERNOON (EARLY EVENING IN THE EAST). THE TEMP FORECAST IS GOING TO ASSUME DIURNAL CONDITIONS ON MONDAY...ALTHOUGH IN REALITY IT MAY NOT QUITE PLAY OUT THAT WAY...WITH THE FRONT CROSSING THE AREA AND OCCASIONAL PRECIPITATION EXPECTED. MAX TEMPS ARE CLOSER TO THE COOL MET GUIDANCE AND SIMILAR TO (OR SLIGHTLY LOWER THAN) THE PREVIOUS FORECAST. SOME OF THE RAW MODELS WERE EVEN LOWER ON TEMPS MONDAY. SKY GRIDS WERE RAISED A BIT ON MONDAY NIGHT...WITH RATHER THICK RH REMAINING IN PLACE THROUGH TUESDAY MORNING ON THE BACK SIDE OF THE TROUGH. && .LONG TERM /TUESDAY THROUGH SUNDAY/... MODELS ARE IN FAIRLY DECENT AGREEMENT IN TERMS OF SYNOPTIC SCALE FEATURES THROUGH THE IMMEDIATE LONG TERM...THEN THEY START TO DIFFER ON TIMING LATE IN THE PERIOD. THE UPPER LEVEL FLOW PATTERN WILL CONTINUE TO SHOW TROUGHS DOMINATING THE WRN AND ERN U.S. WITH RIDGING SPREAD OUT OVER THE SOUTHERN TO CENTRAL PLAINS TO THE MID-LOWER MS VALLEY. ON TUESDAY...UPR LVL LOW WILL DEPART TO THE EAST WHILE A WEAK SFC RIDGE BUILDS QUICKLY INTO THE REGION. A SHOWER MAY LINGER IN THE FAR EAST EARLY ON...OTHERWISE...SKIES WILL BECOME PARTLY TO MOSTLY SUNNY. THERE IS NOT A LOT OF CAA BEHIND DEPARTING SYSTEM SO TEMPERATURES SHOULD REBOUND INTO THE LOWER AND PERHAPS MID 80S NEAR THE TRI-STATE AREA. MODELS CONTINUE TO KEY ON A DISTINCT S/WV WHICH WILL ROUND THE PERIPHERY OF THE RIDGE IN THE NRN PLAINS AND WILL SUBSEQUENTLY DIVE SE INTO THE OHIO VALLEY REGION LATE WEDNESDAY NIGHT INTO THURSDAY. BEFORE THIS HAPPENS...RETURN FLOW AND A DEVELOPING LOW LEVEL JET WILL ALLOW A WARM FRONT TO PIVOT TOWARD THE REGION TUESDAY NIGHT. THIS MAY LEAD TO SOME SHOWER/THUNDERSTORM DEVELOPMENT AFTER MIDNIGHT. ON WEDNESDAY...WARM FRONT WILL NUDGE INTO OUR REGION WHILE A PSEUDO WEST TO EAST FRONTAL BOUNDARY DEVELOPS TO OUR NORTH. THESE FEATURES WILL SERVE AS A FOCUS FOR SHOWERS AND STORMS WEDNESDAY WITH THE GREATEST ACTIVITY/COVERAGE EXPECTED WEDNESDAY NIGHT INTO THURSDAY MORNING AS S/WV ENERGY INTERACTS WITH THE FRONTAL BOUNDARY/WEAK SFC WAVE AS THEY PUSH EAST/SOUTHEAST THROUGH THE REGION. IT CONTINUES TO APPEAR THAT THE ATMOSPHERE COULD BECOME RATHER UNSTABLE WEDNESDAY AFTERNOON AND NIGHT...WITH THUNDERSTORMS LIKELY CONGEALING INTO AN MCS WITH THE POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS. IN ADDITION...THE PARAMETERS ARE RIPE FOR HEAVY RAINFALL AS WELL WITH PWATS APPROACHING 2 INCHES AND WARM CLOUD DEPTH IN EXCESS OF 4 KM. THERE IS STILL SOME UNCERTAINTY THIS FAR OUT IN TIME BUT WILL CONTINUE TO MONITOR GUIDANCE TRENDS. WILL ALSO CONTINUE TO MENTION THESE HAZARDS IN THE EXTENDED HWO. HIGHS ON WEDNESDAY WILL BE CLOUD AND RAIN DEPENDENT RANGING FROM THE LOWER 80S NORTH TO NEAR 90 SOUTH. IT WILL ALSO BE QUITE HUMID. LOWS WEDNESDAY NIGHT WILL GENERALLY BE IN THE 60S WITH COOLER WEATHER ON TAP ON THURSDAY IN THE WAKE OF THE FRONT. PCPN ON THURSDAY SHOULD END FROM NW TO SE THROUGH THE DAY. FOR THURSDAY NIGHT INTO FRIDAY...HIGH PRESSURE WILL BUILD INTO OUR REGION. DRIER WEATHER AND NEAR SEASONAL TEMPERATURES ARE EXPECTED. THE HIGH WILL MOVE OFF TO THE EAST ON SATURDAY AS NW FLOW OVER THE REGION BRINGS PERHAPS AN EMBEDDED DISTURBANCE LATE IN THE DAY. WILL KEEP A LOW THREAT FOR SHOWERS/STORMS ACRS THE NW. FOR SATURDAY NIGHT AND SUNDAY...A MORE BONAFIDE COLD FRONT WILL APPROACH THE REGION FROM THE NORTHWEST. TIMING IS AN ISSUE STILL THIS FAR OUT SO WILL KEEP POPS IN THE CHANCE CATEGORY AT THIS POINT. TEMPERATURES THIS WEEKEND SHOULD WARM TO NEAR OR SLIGHTLY ABOVE NORMAL READINGS. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... AREA OF SHRA LIFTING N THRU THE NRN TAFS IS BEING HANDLED PRETTY WELL BY THE HIGHER RESOLUTION MODELS. THEY TAKE THIS ACTIVITY N OF THE TAFS OVER THE NEXT FEW HOURS. TAFS WILL THEN BE IN A LULL FOR A FEW HOURS UNTIL THE CONVECTION OUT WEST WORKS IN AFT 04-06Z. THIS CONVECTION IS BEING DRIVEN BY THE DIGGING H5 LOW. EARLIER RUNS OF THE HRRR AND RAP SHOWED THE LULL THIS EVENING...THEN BROUGHT CONVECTION TO THE OH/IN BORDER BY 06Z...AND SWUNG IT INTO THE TAFS BETWEEN 06-12Z. WENT WITH A PERIOD OF TEMPO MVFR TSRA AT THE TAFS AS THESE STORMS WORK ACROSS THE TAFS. THE SFC LOW AND FRONT WORK ACROSS THE TAFS BETWEEN 12-16Z...PUSHING THE TSRA EWD. BROUGHT BACK A VCTS FOR LATE MORNING INTO AFTN AS MODELS DESTABILIZE THE ATMOSPHERE AND H5 LOW SWINGS ACROSS THE OH VALLEY. THE MONDAY AFTN CONVECTION SHOULD BE OF THE SCT NATURE. OUTLOOK...THUNDERSTORMS EXPECTED WEDNESDAY NIGHT INTO THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM...HATZOS SHORT TERM...HATZOS LONG TERM...HICKMAN AVIATION...SITES
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
716 PM EDT SUN JUN 9 2013 .SYNOPSIS... A WARM FRONT WILL MOVE NORTHWARD ACROSS OHIO AND NW PA TONIGHT. LOW PRESSURE WILL MOVE ACROSS THE EASTERN GREAT LAKES ON MONDAY. THE COLD FRONT ASSOCIATED WITH THIS LOW WILL THEN STALL OVER OHIO FOR THE MIDDLE OF THE WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... SHOWERS HAVE MOVE UP INTO DAYTON AND SHOULD BE AT FINDLAY AND MARION AROUND 8 PM. LITTLE THUNDER LEFT IN THEM. OCCASIONAL SHOWER AND POSSIBLY A THUNDERSTORM WILL OCCUR FOR THE REMAINDER OF THE NIGHT. THE UNCERTAINTY AT THIS POINT IS HOW FAST THE PRECIP WILL SPREAD TO THE EAST. EXPECT THIS WILL TAKE SOME TIME WITH MOST OF OUR OH COUNTIES GETTING SOME RAIN AROUND OR SHORTLY AFTER MIDNIGHT. IT DOES NOT APPEAR THAT THERE WILL BE ANY SEVERE WEATHER AT THIS TIME...IN FACT WILL CONTINUE TO MONITOR TRENDS TO SEE IF THUNDER CHANCES CAN BE LOWERED SOME FOR OVERNIGHT. THERE MAY BE SOME LOCALIZED HEAVIER RAINFALL ACROSS THE WEST IF ANY TRAINING OF THE ECHOES CAN OCCUR. TEMPERATURES SHOULD REMAIN FAIRLY WARM TONIGHT WITH THE INCREASED MOISTURE LEVELS AND THE CLOUD COVER. EXPECT TO SE LOWS IN THE 60S AT MOST LOCATIONS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... SHOWERS WILL CONTINUE MOST OF THE DAY ON MONDAY AS THE LOW MOVES ACROSS THE EASTERN GREAT LAKES. IT WILL BE SLOW TO TAPER OFF THE SCATTERED SHOWERS MONDAY EVENING. ADDITIONAL JET ENERGY MOVING THROUGH THE NW FLOW WILL LIKELY KEEP THE SCATTERED SHOWERS OVER EASTERN HALF OF THE REGION INTO TUESDAY. UNFORTUNATELY THE COLD FRONT WILL STALL OVER CENTRAL OHIO TUESDAY NIGHT INTO WEDNESDAY WITH ANOTHER RIPPLE OF LOW PRESSURE MOVING ALONG IT. THIS WILL BRING A RETURN OF SHOWERS BY WEDNESDAY MORNING. IT APPEARS THE CHANCES OF SHOWERS WILL INCREASE INTO WEDNESDAY AFTERNOON AND EVENING WITH THE HEAVIEST RAIN LIKELY ACROSS THE SOUTHERN HALF OF THE COUNTY WARNING AREA. WE WILL MONITOR THIS OVER THE NEXT COUPLE DAYS. SHOWERS AND THE ISOLATED THUNDER ON MONDAY WILL KEEP TEMPERATURES COOLER ON MONDAY BUT IT STILL LOOKS AS IF IT WILL REACH THE LOWER TO MID 70S. WARMER ON TUESDAY AND WEDNESDAY IF WE CAN GET SOME BREAKS WITH HIGHS IN THE MIDDLE AND UPPER 70S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AMPLIFICATION OF UPPER LEVEL RIDGE TAKES PLACE OVER THE CENTRAL UNITED STATES BY MID WEEK ALLOWING DIGGING TROUGH TO DIVE DOWN THE EAST COAST. UNFORTUNATELY...THIS DOES NOT FAVOR WELL FOR WARMER TEMPERATURES GOING INTO THE END OF THE WEEK. OUR SAVING GRACE WILL BE THE FACT THE UPPER LEVEL RIDGE MOVES FAIRLY QUICKLY EAST ALLOWING SURFACE HIGH TO PUSH EAST OF THE AREA BY SATURDAY. ONCE THIS TAKES PLACE...A RETURN TO WARM SOUTHERLY COMPONENT WINDS WILL DEVELOP ALLOWING FOR WARM AIR ADVECTION TO TAKE PLACE INTO THE WEEKEND. AS THE SURFACE HIGH PRESSURE BUILDS SOUTHEAST ACROSS THE AREA ON THURSDAY...THE PRECIPITATION THAT IS EXPECTED TO HANG AROUND FOR A GOOD PORTION OF THE FIRST HALF OF THE WEEK WILL FINALLY EXIT STAGE RIGHT. THIS WILL BRING FAIR WEATHER BACK TO THE FORECAST AREA INTO THE WEEKEND. HOWEVER...A FAST MOVING UPPER LEVEL POSITIVE VORTICITY MAXIMUM WILL RACE SOUTHEAST TOWARD THE AREA SATURDAY INTO SUNDAY. THIS FEATURE HAS LIMITED MOISTURE AND COULD BRING A MINIMAL CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY SATURDAY NIGHT INTO SUNDAY. NEARLY ZONAL FLOW DEVELOPS BY SUNDAY AND THIS SHOULD ALLEVIATE ANY STRONG SURGES OF COLD AIR INTO THE AREA FOR A SHORT PERIOD. BUT THIS WILL BE SHORT LIVED AS A RETURN TO AN AMPLIFIED RIDGE IN THE WEST AND TROUGH IN THE EAST WILL DEVELOP AFTER THE WEEKEND. && .AVIATION /23Z SUNDAY THROUGH FRIDAY/... RADAR SHOWS SHOWERS MOVING NORTH/NORTHEAST OUT OF SWRN OHIO THIS EVENING. CIGS WITH THIS REMAIN VFR WITH CIG HEIGHTS LOWERING TO ABOUT BKN-OVC050-060. EXPECT THIS TO MOVE INTO THE AREA IMPACTING KFDY AND KMFD FIRST BETWEEN 8 AND 9PM AND THEN CONTINUING TO SPREAD ACROSS THE AREA AS IT THINS. THE HRRR SHOWS THIS WELL...FOLLOWED BY SHOWERS AND POSSIBLY THUNDERSTORMS MOVING IN FROM THE WEST AFTER MIDNIGHT AS UPPER LOW PRESSURE APPROACHES THE AREA FROM THE WEST. AFTER 06Z THE NAM ALSO SHOWS DEEP MOISTURE FILLING IN ACROSS THE AREA. WILL BRING CIGS AND VISIBILITIES DOWN TO MVFR AFTER MIDNIGHT FROM THE WEST WITH IFR LIKELY AT TIMES LATE TONIGHT AND EARLY MONDAY MORNING IN LOW CIGS AND/OR RAIN/FOG/MIST. MOISTURE AND INSTABILITY IN PLACE MONDAY AFTERNOON SO WOULD EXPECT ADDITIONAL SHOWERS AND POSSIBLY THUNDERSTORMS TO AGAIN TAKE/SUSTAIN CONDITIONS TO NON VFR. .OUTLOOK...NON VFR CONDITIONS LIKELY MONDAY NIGHT IN SHRA/TSRA AND POSSIBLY AGAIN WEDNESDAY AFTERNOON INTO THURSDAY. && .MARINE... THE LAKE APPEARED IT WILL REMAIN RELATIVELY QUIET FOR THE MOST PART. THERE IS THE POSSIBILITY THAT WE COULD SEE SMALL CRAFT CONDITIONS DEVELOP FROM THE ISLANDS WEST LATE TONIGHT INTO MONDAY MORNING. HOWEVER...IT APPEARS THIS WILL BE VERY SHORT LIVED AS WINDS DIMINISH BY LATE MONDAY MORNING. ONCE WE GET PAST MONDAY MORNING...THE GRADIENT APPEARS THAT IT WILL NOT GET TO TIGHT THROUGH FRIDAY AND THIS SHOULD RESULT IN RELATIVELY CALM WINDS AND WAVES ON THE LAKE. THE PROBLEM WILL BE THE PRECIPITATION THREAT EXPECTED FROM TONIGHT THROUGH THURSDAY MORNING WITH IMPROVEMENT BY FRIDAY AS HIGH PRESSURE BUILDS INTO THE REGION. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...MULLEN NEAR TERM...MULLEN SHORT TERM...MULLEN/OUDEMAN LONG TERM...LOMBARDY AVIATION...TK MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
222 AM EDT SAT JUN 8 2013 .SYNOPSIS... THE REMNANTS OF TROPICAL STORM ANDREA WILL MOVE UP THE EASTERN SEABOARD OVERNIGHT. A WEAK RIDGE WILL BRIEFLY BUILD OVER THE REGION LATE THIS WEEKEND. HOWEVER...ANOTHER UPPER LEVEL TROUGH WILL ROLE EASTWARD INTO PENNSYLVANIA LATE SUNDAY AND THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... HAVE GOTTEN RID OF ALL HEADLINES ANS THE LAST VESTIGE OF TROPICAL STORM ANDREA HAS PASSED EASTWARD OF MY CWA. THE RUC AND OTHER SHORT RANGE MODELS HAVE 0.25 TO 0.5 OVER THE SOUTH EAST FOR THE REST OF THE NIGHT. AS THEY HAVE BEEN OVERDONE ALREADY...WILL TREND POPS AND QPF LOWER. THE STRONG NORTH TO NORTHWESTERLY FLOW IS STILL MAINTAINING OROGRAPHIC SHOWERS ALONG THE LAURELS AND ALLEGHENIES...AND THROUGH THE NW MTNS. THESE ARE QUASI STATIONARY AND ARE SLOWLY MOVING EASTWARD. AS THE OUTPUTS FOR THESE ARE AT A 0.10 OR LESS...ARE NOT CONCERNED WITH ANY LOCALIZED FLOODING. LOWS OVERNIGHT WILL BE COOL BUT WILL BE TEMPERED BY THE CLOUDY SKIES EXPECT LOW 50S IN THE NW TO UPPER 50S IN THE SOUTHEAST. THE COPIOUS AMOUNTS OF MOISTURE AND LIGHT WINDS WILL ALLOW FOR PATCHY FOG OVERNIGHT...MAINLY IN THE LOW LYING REGIONS AND VALLEYS...BUT CAN/T RULE OUT IT SPREADING...THOUGH THE LOW STRATOCU WILL HAMPER THIS DEVELOPMENT. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/... A WEAK RIDGE WILL MOVE OVER THE REGION SATURDAY AND THE LINGERING MOISTURE WILL KEEP DEWPOINTS HIGHER...ALLOWING IT TO BE A BIT MUGGY...AS THE CLEARING SKIES WILL BRING TEMPERATURES SEVERAL DEG WARMER THAN TODAY. SHORT RANGE OPERATIONAL MODELS DIFFER A BIT IN TRYING TO INITIATE A FEW SHOWERS UNDER THE BUILDING UPPER HEIGHTS. THE SREF AND GEFS DOWNPLAY THINGS SO HAVE LIMITED POPS TO SLIGHT CHANCE IN THE AFTERNOON. THINKING IS THAT WE WILL START THE DAY CLOUDY WITH BRIGHTENING SKIES AND JUST AN ISOLATED SHOWER OR TWO IN THE AFTERNOON. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... BROAD TROUGHING CENTERED NEAR 90W TO BEGIN THE PERIOD WILL AMPLIFY TO THE EAST OF 90W AS ANOTHER UPPER TROF DIGS INTO THE UPPER MIDWEST. THIS WILL BRING A BRIEF RESPITE FROM CLOUDY AND SHOWERY CONDITIONS SATURDAY NIGHT INTO SUNDAY BEFORE DETERIORATING CONDITIONS RETURN WITH THE AFOREMENTIONED UPPER TROF MON THROUGH WEDNESDAY. DRIER AIR WILL WORK ACROSS THE EASTERN GREAT LAKES AND INTO THE NORTHEAST AT THE END OF THIS WEEK AND OVER THE WEEKEND AS UPPER RIDGING AND CANADIAN HIGH PRESSURE COMBINE TO FINALLY NUDGE THE DECAYING UPPER LOW OFF OF THE EAST COAST. THE WETTEST TIMEFRAME WOULD APPEAR TO COME MONDAY NIGHT INTO TUESDAY AS INCREASING DEEP LAYER MOISTURE IS TAPPED BY BROAD SOUTHWEST FLOW AND ADVECTED TO THE EASTERN GREAT LAKES AND POINTS EASTWARD. THE UPPER LOW IS EXPECTED TO LIFT THROUGH THE ERN GLAKS MON AND TUE BEFORE SLOWLY PROPAGATING ACROSS NRN NEW ENGLAND AND SOUTHEAST CANADA FOR MUCH OF THE REST OF THE WEEK. MEDIUM RANGE GUIDANCE SUGGESTS DRIER AIR APPROACHES IN DEVELOPING NORTHWEST FLOW BEHIND THE UPPER TROF FOR THURSDAY AND FRIDAY...BUT A WEAKNESS IN THE UPPER FLOW MAY KEEP CYCLONIC CIRCULATION AND A CHC OF DIURNAL SHOWERS OVER CENTRAL PA INTO FRIDAY. COMPLICATING THINGS IS THE POSSIBILITY OF CYCLOGENESIS TO MY SOUTH AND DEEP EASTERLY FLOW AROUND THE BROAD SFC HIGH EXTENDING FROM THE WESTERN GLAKS TO WELL OFF OF THE SOUTHERN NEW ENGLAND COAST...WHICH COULD TAP WESTERN ATLANTIC MOISTURE AND BRING COOL/DRIZZLY SHOWERY CONDITIONS NEXT WEEKEND. PLAYED THINGS OPTIMISTICALLY AT THIS POINT TRENDING FOR DRIER CONDITIONS WITH THE HIGH...AND WE`LL SEE HOW THE EASTERLY FLOW AND FETCH OF WESTERN ATLANTIC MOISTURE EVOLVES IN THE COMING DAYS. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... THE REMNANTS OF TROPICAL STORM ANDREA WILL CONTINUE TO MOVE UP THE EASTERN SEABOARD OVERNIGHT...BUT ITS IMPACTS WILL BE LARGELY EAST OF CWA. NORTH TO NORTHWESTERLY FLOW WILL STILL MAINTAINING IFR/MVFR OROGRAPHIC CLOUDS ALONG THE LAURELS AND ALLEGHENIES AND THROUGH THE NW MTNS OVERNIGHT...WHILE DOWNSLOPE FLOW WILL EVENTUALLY BRING VFR CIGS TO THE SE /WITH TEMPORARY MVFR CIGS UNTIL THEN/. RESIDUAL LOW LEVEL MOISTURE AND LIGHT SFC WINDS WILL ALSO BRING MVFR FOG OVERNIGHT. LINGERING LIGHT SHOWERS WILL CONTINUE TO DECREASE THROUGH 09Z ACROSS CENTRAL AND NORTHERN MTNS. IMPROVING CONDITIONS SATURDAY...WITH VFR BECOMING MORE WIDESPREAD BY LATE MORNING AS THE STORM PULLS FURTHER OFF TO OUR EAST AND DRIER AIR BEGINS TO MOVE INTO THE REGION. THE NEXT SYSTEM SHOULD MOVE THROUGH SUNDAY AFTERNOON AND ONCE AGAIN REDUCE CIGS AND VSBYS. OUTLOOK... SAT...EARLY IFR/MVFR...THEN IMPROVING CONDITIONS. SUN...VFR WITH SCATTERED PM THUNDERSTORM IMPACTS MAINLY IN THE SW. SUN NIGHT-TUES...SCT-NUMEROUS SHOWERS /ESP MON-MON NIGHT/. SCT PM TSRA. LOCAL RESTRICTIONS. WED...NO SIG WX. && .HYDROLOGY... ANY REMNANTS HAVE MOVED EASTWARD AND QPF WILL BE 0.5 OR LOWER FOR ANY ZONES THAT HAVE ALREADY RECEIVED ANY PRECIPITATION. SO HAVE DROPPED ALL HEADLINES. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CERU NEAR TERM...LA CORTE/CERU SHORT TERM...LA CORTE/CERU LONG TERM...DEVOIR/FITZGERALD AVIATION...RXR HYDROLOGY...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1039 PM EDT SUN JUN 9 2013 .SYNOPSIS... MOIST SOUTHERLY FLOW WILL CONTINUE AHEAD OF AN APPROACHING UPPER LOW PRESSURE TROUGH TONIGHT. THE TROUGH WILL PUSH A COLD FRONT INTO THE REGION MONDAY NIGHT...FOLLOWED BY HIGH PRESSURE TUESDAY AND WEDNESDAY. ANOTHER FRONT IS EXPECTED TO MOVE ACROSS THE AREA LATE IN THE WEEK. && .NEAR TERM /THROUGH MONDAY/... AS OF 1040 PM EDT...THE FORECAST REMAINS ON TRACK...WITH STEADY LIGHT TO MODERATE SHOWERS ACROSS THE AREA LATE THIS EVENING...BUT WITH HEAVIER RATES BLOSSOMING FROM THE SOUTH AND SOUTHEAST. THE LATEST SHORT RANGE MODELS CONTINUE TO FEATURE ROBUST QPF DURING THE OVERNIGHT HOURS. GIVEN THE EXPECTED HIGH PRECIPITABLE WATER VALUES...SATURATED GROUND AND IMPROVING FORCING...THE FLASH FLOOD WATCH REMAINS IN PLACE. OTHERWISE...THE UPPER TROUGH CONTINUES TO SHARPEN UP OVER THE MID MS RIVER VALLEY. ANTICIPATE IMPROVING AND SLIGHTLY BACKING FLOW ACROSS THE REGION TO ALLOW CONVECTION TO REGENERATE AND PERHAPS STRENGTHEN THROUGH THE OVERNIGHT HOURS. A LOW END SEVERE THREAT WILL LINGER GIVEN THE IMPROVING WIND SHEAR AND EASILY REACHABLE LCL HEIGHTS. GIVEN THE ROBUST 0 TO 3 KM BULK SHEAR VALUES NOW ADVERTISED ON THE LATEST RUC RUNS FOR THE OVERNIGHT...HAVE FEATURED AN ISOLD TORNADO MENTION IN THE HWO. CONDITIONS ON MONDAY WILL REMAIN FAVORABLE FOR HEAVY RAIN PRODUCING THUNDERSTORMS...WITH UNSTABLE SOUNDINGS ACROSS THE REGION AS THE UPPER TROUGH MOVES IN. A SFC COLD FRONT WILL ENTER THE MTNS FROM THE WEST AROUND MIDDAY. A DRY SLOT AHEAD OF THE FRONT WILL START TO DIMINISH POPS FROM WEST TO EAST. ONCE AGAIN...DEEP SHEAR CONTINUES TO INCREASE WITH THE ARRIVAL OF THE TROUGH...SO STORMS AHEAD OF THE FRONT MAY BE QUITE VIGOROUS...ESPECIALLY IN ERN SECTIONS. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 1245 PM SUNDAY...LINGERING DEEP CONVECTIVE CHANCES WILL REMAIN IN THE FORECAST THRU MONDAY NIGHT SINCE THE 09/12 UTC OP SHORT RANGE MODELS CONTINUE TO ADVERTISE THE PASSAGE OF A SHARP LOOKING S/WV TROUGH. WITH THE LATEST NAM RUN NOW IN STEP WITH THE OP GFS IN TRANSLATING UPPER TROUGH AXIS DOWNSTREAM OF THE CWFA BY TUESDAY AFTERNOON...WITH PLAN ON SHAVING BACK POP A BIT MORE...ESPECIALLY GIVING THE PALTRY MOS POPS...FALLING SFC DWPTS AND SOME DOWNSLOPE FLOW. MAX TEMPERATURES REMAIN SLATED TO REBOUND TO VALUES VERY CLOSE TO CLIMO. THE CWFA WILL BE UNDER BROADLY DIFFLUENT WNW FLOW ALOFT TUESDAY NIGHT INTO WEDNESDAY AND IT IS WITHIN THE REALM OF POSSIBILITY THAT OHIO VALLEY MCS ACTIVITY WILL MAKE A RUN AT THE NW CWFA BY WED AM...BUT CONFIDENCE IS STILL NOT HIGH ENUF TO INTRODUCE ANYTHING AT THIS POINT. UNLESS IT BECOMES OBVIOUS THAT AN IMPULSE/OUTFLOW IS GOING TO MAKE IT/S WAY ACRS THE CWFA WEDNESDAY WILL PLAN ON LIMITING DIURNAL TSTM CHANCES TO THE MTNS/LEE TROUGH LOCALES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1130 AM EDT SUNDAY...A BROAD UPPER RIDGE OF H5 HIGH WILL REMAIN ANCHORED ACROSS THE SOUTHERN PLAINS...LEAVING OUR FORECAST AREA UNDER N/NW FLOW ALOFT THROUGH MUCH OF THE MEDIUM RANGE PERIOD. AT THE SURFACE...A WEAK SURFACE HIGH PRESSURE WILL PREVAIL WED NIGHT INTO THURSDAY ACROSS THE REGION PROVIDING MOSTLY DRY CONDITIONS. A COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION THU NIGHT INTO EARLY FRI. MODELS AGREE THAT THE FRONT WILL WEAKEN AS IT CROSSES THE CWA. HENCE...I HAVE CARRIED LOW END CHANCE POPS DURING THIS PERIOD. CONDITIONS LOOK DRY FOR THE NEXT WEEKEND WITH HIGH PRESSURE BUILDING ACROSS THE REGION. TEMPS ON THURSDAY WILL BE AROUND 3-5 DEGREES ABOVE NORMAL WITH HIGHS REACHING THE LOW 90S EAST OF THE MTNS. THEN TEMPS BACK TO NEAR...OR A FEW DEGREES BELOW NORMAL FRI/SAT BEFORE WARMING UP TO NEAR NORMAL SUN. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... AT KCLT...CONVECTIVE ACTIVITY HAS WANED LATE THIS EVENING AS THE KCLT REGION REMAINS FAIRLY STABLE FROM EARLIER CONVECTION. STILL ANTCIPATE SHRA COVERAGE TO BECOME FAIRLY WIDESPREAD AT TIMES DURING THE OVERNIGHT HOURS...WITH TSTMS POSSIBLY ORGANIZING AGAIN AS LOW LEVEL WIND SHEAR GRADUALLY IMPROVES. WILL FEATURE A DOWNWARD TRANSITION ON CIGS THROUGH MVFR WITH IFR LIKELY BEFORE DAYBREAK. TSRA WILL MAKE A RETURN MAINLY AFTER 06Z AND THEN POSSIBLY AGAIN THROUGH THE DAY ON MONDAY. EXPECT SRLY FLOW...WITH GUSTS DEVELOPING AT TIMES WITH MIXING THROUGH MONDAY. ELSEWHERE...WIDESPREAD MODERATE TO OCCASIONALLY HEAVY RAIN CAN BE EXPECTED AT THE MOUNTAIN AND FOOTHILL SITES THROUGH THE PERIOD. INSTABILITY HAS GREATLY LESSENED THIS EVENING...BUT ANOTHER ROUND OF CONVECTION WILL LIKELY DEVELOP FROM THE SW AHEAD OF THE SHARPENING UPPER TROUGH AS LOW LEVEL FLOW IMPROVES. WILL FEATURE TEMPO TSRA AT MOST SITES DURING THE OVERNIGHT HOURS...WITH VCTS LIKELY THROUGH MONDAY. EXPECT CIGS TO FALL INTO THE IFR RANGE AT MOST TAF LOCATIONS OVERNIGHT AND ONLY SLOWLY RECOVER MON. SRLY FLOW WILL PERSIST...WITH LOW END GUSTS POSSIBLE AT TIMES THROUGH MONDAY. OUTLOOK...A COLD FRONT WILL CROSS THE REGION MONDAY NIGHT WITH CONTINUED SHOWERS AND STORMS...ESPECIALLY IN ERN SECTIONS. CONDITIONS WILL IMPROVE ON TUE IN THE MIDWEEK AS UPPER LEVEL HIGH PRESSURE BUILDS IN. THUNDERSTORMS COULD ARRIVE FROM THE NORTHWEST LATE WED AND AGAIN ON THU. CONFIDENCE TABLE... 02-08Z 08-14Z 14-20Z 20-02Z KCLT HIGH 95% HIGH 100% HIGH 91% HIGH 90% KGSP MED 71% HIGH 90% HIGH 85% HIGH 100% KAVL HIGH 95% HIGH 98% HIGH 86% HIGH 100% KHKY HIGH 89% HIGH 95% HIGH 84% HIGH 100% KGMU MED 77% HIGH 95% HIGH 85% HIGH 100% KAND HIGH 90% HIGH 97% HIGH 95% 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...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR GAZ010-017-018- 026-028-029. NC...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR NCZ033-035>037- 048>053-056>059-062>065-068>072-082-501>510. SC...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR SCZ001>014-019. && $$ SYNOPSIS...JOH NEAR TERM...HG/WIMBERLEY SHORT TERM...CSH LONG TERM...JOH AVIATION...HG/WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
851 PM EDT SUN JUN 9 2013 .SYNOPSIS... MOIST SOUTHERLY FLOW WILL CONTINUE AHEAD OF AN APPROACHING UPPER LOW PRESSURE TROUGH TONIGHT. THE TROUGH WILL PUSH A COLD FRONT INTO THE REGION MONDAY NIGHT...FOLLOWED BY HIGH PRESSURE TUESDAY AND WEDNESDAY. ANOTHER FRONT IS EXPECTED TO MOVE ACROSS THE AREA LATE IN THE WEEK. && .NEAR TERM /THROUGH MONDAY/... AS OF 850 PM EDT...BLOSSOMING COVERAGE OF MODERATE TO HEAVY RAINFALL...THE ROBUST QPF DEPICTED BY THE LATEST SHORT RANGE MODELS...AND THE HIGH PRECIPITABLE WATER VALUES...HAVE DECIDED TO POST A FLASH FLOOD WATCH FOR THE AREA THROUGH MONDAY. WE SHOULD SEE THE RATES INCREASE ENOUGH WITH OVERNIGHT CONVECTION TO POSE AN INCREASING RISK OF MORE THAN ISOLD FLASH FLOODING. OTHERWISE...THE UPPER TROUGH CONTINUES TO SHARPEN UP OVER THE MID MS RIVER VALLEY. ANTICIPATE IMPROVING AND SLIGHTLY BACKING FLOW ACROSS THE REGION TO ALLOW CONVECTION TO REGENERATE AND PERHAPS STRENGTHEN THROUGH THE OVERNIGHT HOURS. A LOW END SEVERE THREAT WILL LINGER GIVEN THE IMPROVING WIND SHEAR AND EASILY REACHABLE LCL HEIGHTS. GIVEN THE ROBUST 0 TO 3 KM BULK SHEAR VALUES NOW ADVERTISED ON THE LATEST RUC RUNS FOR THE OVERNIGHT...HAVE FEATURED AN ISOLD TORNADO MENTION IN THE HWO. CONDITIONS ON MONDAY WILL REMAIN FAVORABLE FOR HEAVY RAIN PRODUCING THUNDERSTORMS...WITH UNSTABLE SOUNDINGS ACROSS THE REGION AS THE UPPER TROUGH MOVES IN. A SFC COLD FRONT WILL ENTER THE MTNS FROM THE WEST AROUND MIDDAY. A DRY SLOT AHEAD OF THE FRONT WILL START TO DIMINISH POPS FROM WEST TO EAST. ONCE AGAIN...DEEP SHEAR CONTINUES TO INCREASE WITH THE ARRIVAL OF THE TROUGH...SO STORMS AHEAD OF THE FRONT MAY BE QUITE VIGOROUS...ESPECIALLY IN ERN SECTIONS. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... AS OF 1245 PM SUNDAY...LINGERING DEEP CONVECTIVE CHANCES WILL REMAIN IN THE FORECAST THRU MONDAY NIGHT SINCE THE 09/12 UTC OP SHORT RANGE MODELS CONTINUE TO ADVERTISE THE PASSAGE OF A SHARP LOOKING S/WV TROUGH. WITH THE LATEST NAM RUN NOW IN STEP WITH THE OP GFS IN TRANSLATING UPPER TROUGH AXIS DOWNSTREAM OF THE CWFA BY TUESDAY AFTERNOON...WITH PLAN ON SHAVING BACK POP A BIT MORE...ESPECIALLY GIVING THE PALTRY MOS POPS...FALLING SFC DWPTS AND SOME DOWNSLOPE FLOW. MAX TEMPERATURES REMAIN SLATED TO REBOUND TO VALUES VERY CLOSE TO CLIMO. THE CWFA WILL BE UNDER BROADLY DIFFLUENT WNW FLOW ALOFT TUESDAY NIGHT INTO WEDNESDAY AND IT IS WITHIN THE REALM OF POSSIBILITY THAT OHIO VALLEY MCS ACTIVITY WILL MAKE A RUN AT THE NW CWFA BY WED AM...BUT CONFIDENCE IS STILL NOT HIGH ENUF TO INTRODUCE ANYTHING AT THIS POINT. UNLESS IT BECOMES OBVIOUS THAT AN IMPULSE/OUTFLOW IS GOING TO MAKE IT/S WAY ACRS THE CWFA WEDNESDAY WILL PLAN ON LIMITING DIURNAL TSTM CHANCES TO THE MTNS/LEE TROUGH LOCALES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1130 AM EDT SUNDAY...A BROAD UPPER RIDGE OF H5 HIGH WILL REMAIN ANCHORED ACROSS THE SOUTHERN PLAINS...LEAVING OUR FORECAST AREA UNDER N/NW FLOW ALOFT THROUGH MUCH OF THE MEDIUM RANGE PERIOD. AT THE SURFACE...A WEAK SURFACE HIGH PRESSURE WILL PREVAIL WED NIGHT INTO THURSDAY ACROSS THE REGION PROVIDING MOSTLY DRY CONDITIONS. A COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION THU NIGHT INTO EARLY FRI. MODELS AGREE THAT THE FRONT WILL WEAKEN AS IT CROSSES THE CWA. HENCE...I HAVE CARRIED LOW END CHANCE POPS DURING THIS PERIOD. CONDITIONS LOOK DRY FOR THE NEXT WEEKEND WITH HIGH PRESSURE BUILDING ACROSS THE REGION. TEMPS ON THURSDAY WILL BE AROUND 3-5 DEGREES ABOVE NORMAL WITH HIGHS REACHING THE LOW 90S EAST OF THE MTNS. THEN TEMPS BACK TO NEAR...OR A FEW DEGREES BELOW NORMAL FRI/SAT BEFORE WARMING UP TO NEAR NORMAL SUN. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... AT KCLT...CONVECTIVE ACTIVITY HAS GREATLY WEAKENED THIS EVENING AS THE CLT REGION CONTINUES TO STABILIZE FOLLOWING THE EARLIER HEAVY RAINFALL. SHRA COVERAGE SHOULD BE FAIRLY WIDESPREAD AT TIMES DURING THE OVERNIGHT HOURS...WITH TSTMS POSSIBLY ORGANIZING AGAIN AS LOW LEVEL WIND SHEAR GRADUALLY IMPROVES. WILL FEATURE A STEADY TRANSITION ON CIGS DOWN THROUGH MVFR WITH IFR LIKELY BEFORE DAYBREAK. TSRA WILL MAKE A RETURN MAINLY AFTER 06Z AND THEN POSSIBLY AGAIN THROUGH THE DAY ON MONDAY. EXPECT SRLY FLOW...WITH GUSTS DEVELOPING AT TIMES WITH MIXING THROUGH MONDAY. ELSEWHERE...WIDESPREAD MODERATE TO OCCASIONALLY HEAVY RAIN CAN BE EXPECTED AT THE MOUNTAIN AND FOOTHILL SITES THROUGH THE PERIOD. INSTABILITY HAS GREATLY LESSENED THIS EVENING...BUT ANOTHER ROUND OF CONVECTION WILL LIKELY DEVELOP FROM THE SW AHEAD OF THE SHARPENING UPPER TROUGH AS LOW LEVEL FLOW IMPROVES. WILL FEATURE TEMPO TSRA AT MOST SITES DURING THE OVERNIGHT HOURS...WITH VCTS LIKELY THROUGH MONDAY. EXPECT CIGS TO FALL INTO THE IFR RANGE AT MOST TAF LOCATIONS OVERNIGHT AND ONLY SLOWLY RECOVER MON. SRLY FLOW WILL PERSIST...WITH LOW END GUSTS POSSIBLE AT TIMES THROUGH MONDAY. OUTLOOK...A COLD FRONT WILL CROSS THE REGION MONDAY NIGHT WITH CONTINUED SHOWERS AND STORMS...ESPECIALLY IN ERN SECTIONS. CONDITIONS WILL IMPROVE ON TUE IN THE MIDWEEK AS UPPER LEVEL HIGH PRESSURE BUILDS IN. THUNDERSTORMS COULD ARRIVE FROM THE NORTHWEST LATE WED AND AGAIN ON THU. CONFIDENCE TABLE... 01-07Z 07-13Z 13-19Z 19-01Z KCLT HIGH 92% HIGH 98% HIGH 89% HIGH 87% KGSP HIGH 86% HIGH 92% HIGH 86% HIGH 93% KAVL HIGH 100% HIGH 92% HIGH 84% HIGH 100% KHKY HIGH 86% HIGH 95% HIGH 85% HIGH 94% KGMU HIGH 88% HIGH 100% HIGH 85% HIGH 93% KAND MED 75% HIGH 89% HIGH 87% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR GAZ010-017-018- 026-028-029. NC...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR NCZ033-035>037- 048>053-056>059-062>065-068>072-082-501>510. SC...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR SCZ001>014-019. && $$ SYNOPSIS...JOH NEAR TERM...HG/WIMBERLEY SHORT TERM...CSH LONG TERM...JOH AVIATION...HG/WIMBERLEY
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
919 PM CDT SUN JUN 9 2013 .MESOSCALE UPDATE... CONVECTIVE LINE CONTINUING TO HOLD TOGETHER BUT OVERALL WEAKENING HAS OCCURRED DURING THE LAST HOUR. THE ESTIMATED TIME OF ARRIVAL IN DOWNTOWN NASHVILLE IS 1020 PM CDT. BOYD && .PREV DISCUSSION... /ISSUED 857 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE SEGMENT MOVING INTO MONTGOMERY COUNTY REMAINS STRONG OTHERWISE LINE OF CONVECTION OVERALL HAS WEAKENED. EXPECT THIS TREND TO CONTINUE. RAINFALL IN SOUTHWEST BENTON COUNTY TOTALED 1.75 INCHES. FLASH FLOOD GUIDANCE IS JUST ABOVE 2 INCHES FOR THE AREA. THE HEAVIER RAINS HAVE NOW PULLED EAST. BOYD PREV DISCUSSION... /ISSUED 814 PM CDT SUN JUN 9 2013/ UPDATE... HAVE UPDATED GRIDS AND ZONES TO REFLECT BETTER THE APPROACHING SHOWERS AND STORMS NOW CROSSING THE TENNESSEE RIVER. ALTHOUGH A STORM OR TWO COULD BE STRONG TO SEVERE STILL THINK ACTIVITY WILL GENERALLY WEAKEN AS IT MOVES FARTHER EAST INTO MIDDLE TENNESSEE THIS EVENING...WITH LOSS OF HEATING AND UPPER SUPPORT. STATIONARY FRONT FROM WESTERN TENNESSEE DOWN INTO LOUISIANA WITH CONVECTION ALL ALONG THIS BOUNDARY. CLOUDS TOPS HAVE BECOME COLDER LAST COUPLE OF HOURS ALONG THE BOUNDARY WITH SURFACE DEWPOINTS AROUND 70 DEGREES. BOUNDARY MAY WORK INTO WESTERN MIDDLE TENNESSEE OVERNIGHT AND WITH TRAINING OF ECHOES WE COULD BE LOOKING AT LOCALLY HEAVY RAINFALL. BOYD PREV DISCUSSION... /ISSUED 752 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF CONVECTION NEARING TENNESSEE RIVER AT 0030Z HAS PULLED AHEAD OF COLDER AIR ALOFT AND ALONG WITH LOSS OF HEATING EXPECT CONVECTION TO CONTINUE TO WEAKEN AS IT ADVANCES EASTWARD INTO WESTERN MIDDLE TENNESSEE OVER THE NEXT 1 TO 2 HOURS BUT THERE STILL COULD BE A STRONG STORM OR TWO. HAVE SOME CONCERN FOR STATIONARY FRONT THAT EXTENDS FROM WEST TENNESSEE DOWN INTO LOUISIANA AND A WAVE THAT HAS JUST DEVELOPED ON THE FRONT IN LOUISIANA. SURFACE DEWPOINTS AROUND 70 EXTENDS ALL ALONG THIS BOUNDARY. WILL HAVE TO WATCH FOR CONVECTION TRAINING NORTHEAST OVERNIGHT. BOYD PREV DISCUSSION... /ISSUED 704 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF STRONG CONVECTION CURRENTLY MOVING EASTWARD THROUGH WEST TENNESSEE AND WAS 40 MILES WEST OF THE TENNESSEE RIVER AT 00Z. AM EXPECTING THIS ACTIVITY TO WEAKEN AS IT CROSSES THE TENNESSEE RIVER. BOYD PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUN 9 2013/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
857 PM CDT SUN JUN 9 2013 .MESOSCALE UPDATE... LINE SEGMENT MOVING INTO MONTGOMERY COUNTY REMAINS STRONG OTHERWISE LINE OF CONVECTION OVERALL HAS WEAKENED. EXPECT THIS TREND TO CONTINUE. RAINFALL IN SOUTHWEST BENTON COUNTY TOTALED 1.75 INCHES. FLASH FLOOD GUIDANCE IS JUST ABOVE 2 INCHES FOR THE AREA. THE HEAVIER RAINS HAVE NOW PULLED EAST. BOYD && .PREV DISCUSSION... /ISSUED 814 PM CDT SUN JUN 9 2013/ UPDATE... HAVE UPDATED GRIDS AND ZONES TO REFLECT BETTER THE APPROACHING SHOWERS AND STORMS NOW CROSSING THE TENNESSEE RIVER. ALTHOUGH A STORM OR TWO COULD BE STRONG TO SEVERE STILL THINK ACTIVITY WILL GENERALLY WEAKEN AS IT MOVES FARTHER EAST INTO MIDDLE TENNESSEE THIS EVENING...WITH LOSS OF HEATING AND UPPER SUPPORT. STATIONARY FRONT FROM WESTERN TENNESSEE DOWN INTO LOUISIANA WITH CONVECTION ALL ALONG THIS BOUNDARY. CLOUDS TOPS HAVE BECOME COLDER LAST COUPLE OF HOURS ALONG THE BOUNDARY WITH SURFACE DEWPOINTS AROUND 70 DEGREES. BOUNDARY MAY WORK INTO WESTERN MIDDLE TENNESSEE OVERNIGHT AND WITH TRAINING OF ECHOES WE COULD BE LOOKING AT LOCALLY HEAVY RAINFALL. BOYD PREV DISCUSSION... /ISSUED 752 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF CONVECTION NEARING TENNESSEE RIVER AT 0030Z HAS PULLED AHEAD OF COLDER AIR ALOFT AND ALONG WITH LOSS OF HEATING EXPECT CONVECTION TO CONTINUE TO WEAKEN AS IT ADVANCES EASTWARD INTO WESTERN MIDDLE TENNESSEE OVER THE NEXT 1 TO 2 HOURS BUT THERE STILL COULD BE A STRONG STORM OR TWO. HAVE SOME CONCERN FOR STATIONARY FRONT THAT EXTENDS FROM WEST TENNESSEE DOWN INTO LOUISIANA AND A WAVE THAT HAS JUST DEVELOPED ON THE FRONT IN LOUISIANA. SURFACE DEWPOINTS AROUND 70 EXTENDS ALL ALONG THIS BOUNDARY. WILL HAVE TO WATCH FOR CONVECTION TRAINING NORTHEAST OVERNIGHT. BOYD PREV DISCUSSION... /ISSUED 704 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF STRONG CONVECTION CURRENTLY MOVING EASTWARD THROUGH WEST TENNESSEE AND WAS 40 MILES WEST OF THE TENNESSEE RIVER AT 00Z. AM EXPECTING THIS ACTIVITY TO WEAKEN AS IT CROSSES THE TENNESSEE RIVER. BOYD PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUN 9 2013/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
814 PM CDT SUN JUN 9 2013 .UPDATE... HAVE UPDATED GRIDS AND ZONES TO REFLECT BETTER THE APPROACHING SHOWERS AND STORMS NOW CROSSING THE TENNESSEE RIVER. ALTHOUGH A STORM OR TWO COULD BE STRONG TO SEVERE STILL THINK ACTIVITY WILL GENERALLY WEAKEN AS IT MOVES FARTHER EAST INTO MIDDLE TENNESSEE THIS EVENING...WITH LOSS OF HEATING AND UPPER SUPPORT. STATIONARY FRONT FROM WESTERN TENNESSEE DOWN INTO LOUISIANA WITH CONVECTION ALL ALONG THIS BOUNDARY. CLOUDS TOPS HAVE BECOME COLDER LAST COUPLE OF HOURS ALONG THE BOUNDARY WITH SURFACE DEWPOINTS AROUND 70 DEGREES. BOUNDARY MAY WORK INTO WESTERN MIDDLE TENNESSEE OVERNIGHT AND WITH TRAINING OF ECHOES WE COULD BE LOOKING AT LOCALLY HEAVY RAINFALL. BOYD && .PREV DISCUSSION... /ISSUED 752 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF CONVECTION NEARING TENNESSEE RIVER AT 0030Z HAS PULLED AHEAD OF COLDER AIR ALOFT AND ALONG WITH LOSS OF HEATING EXPECT CONVECTION TO CONTINUE TO WEAKEN AS IT ADVANCES EASTWARD INTO WESTERN MIDDLE TENNESSEE OVER THE NEXT 1 TO 2 HOURS BUT THERE STILL COULD BE A STRONG STORM OR TWO. HAVE SOME CONCERN FOR STATIONARY FRONT THAT EXTENDS FROM WEST TENNESSEE DOWN INTO LOUISIANA AND A WAVE THAT HAS JUST DEVELOPED ON THE FRONT IN LOUISIANA. SURFACE DEWPOINTS AROUND 70 EXTENDS ALL ALONG THIS BOUNDARY. WILL HAVE TO WATCH FOR CONVECTION TRAINING NORTHEAST OVERNIGHT. BOYD PREV DISCUSSION... /ISSUED 704 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF STRONG CONVECTION CURRENTLY MOVING EASTWARD THROUGH WEST TENNESSEE AND WAS 40 MILES WEST OF THE TENNESSEE RIVER AT 00Z. AM EXPECTING THIS ACTIVITY TO WEAKEN AS IT CROSSES THE TENNESSEE RIVER. BOYD PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUN 9 2013/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
752 PM CDT SUN JUN 9 2013 .MESOSCALE UPDATE... LINE OF CONVECTION NEARING TENNESSEE RIVER AT 0030Z HAS PULLED AHEAD OF COLDER AIR ALOFT AND ALONG WITH LOSS OF HEATING EXPECT CONVECTION TO CONTINUE TO WEAKEN AS IT ADVANCES EASTWARD INTO WESTERN MIDDLE TENNESSEE OVER THE NEXT 1 TO 2 HOURS BUT THERE STILL COULD BE A STRONG STORM OR TWO. HAVE SOME CONCERN FOR STATIONARY FRONT THAT EXTENDS FROM WEST TENNESSEE DOWN INTO LOUISIANA AND A WAVE THAT HAS JUST DEVELOPED ON THE FRONT IN LOUISIANA. SURFACE DEWPOINTS AROUND 70 EXTENDS ALL ALONG THIS BOUNDARY. WILL HAVE TO WATCH FOR CONVECTION TRAINING NORTHEAST OVERNIGHT. BOYD && .PREV DISCUSSION... /ISSUED 704 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF STRONG CONVECTION CURRENTLY MOVING EASTWARD THROUGH WEST TENNESSEE AND WAS 40 MILES WEST OF THE TENNESSEE RIVER AT 00Z. AM EXPECTING THIS ACTIVITY TO WEAKEN AS IT CROSSES THE TENNESSEE RIVER. BOYD PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUN 9 2013/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
704 PM CDT SUN JUN 9 2013 .MESOSCALE UPDATE... LINE OF STRONG CONVECTION CURRENTLY MOVING EASTWARD THROUGH WEST TENNESSEE AND WAS 40 MILES WEST OF THE TENNESSEE RIVER AT 00Z. AM EXPECTING THIS ACTIVITY TO WEAKEN AS IT CROSSES THE TENNESSEE RIVER. BOYD && .PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUN 9 2013/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
641 PM CDT SUN JUN 9 2013 .UPDATE...FOR 00Z AVIATION FORECAST && .AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. .MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD && .PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
849 PM CDT SUN JUN 9 2013 .DISCUSSION... THIS EVENINGS SOUNDINGS HAVE PRECIPITABLE WATER VALUES OF 1.87 AND 1.56 INCHES. THE ATMOSPHERE IS MORE STABLE THAN IT WAS 24 HOURS AGO...BUT ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE STILL POSSIBLE OVER THE EASTERN PORTIONS OF SOUTHEAST TEXAS TOMORROW AFTERNOON. THE AXIS OF THE UPPER LEVEL TROUGH SHOULD BE JUST OFF THE COAST. WITH SUBSIDENCE OVER THE AREA AND CONVERGENCE AT 200-300 MB. THE COVERAGE SHOULD BE SPOTTIER THAN IT WAS TODAY. OVERALL...THE PREVIOUS FORECAST LOOKS TO BE ON TRACK. NO CHANGES ARE NECESSARY AT THIS TIME. 44 && .PREV DISCUSSION... /ISSUED 622 PM CDT SUN JUN 9 2013/ DISCUSSION... SEE 00Z AVIATION DISCUSSION. AVIATION... CONDITIONS HAVE STABILIZED ACROSS SE TX AND AM EXPECTING THE CIRRUS SHIELD TO DISSIPATE IN THE NEXT HOUR OR SO. CONVECTION SHOULD REMAIN TO THE EAST AND TO THE WEST OF SE TX. AM A LITTLE CONCERNED ABOUT PATCHY FOG IN RURAL AREAS OVERNIGHT WITH GROUNDS REMAINING WET AND LIGHT WINDS. FCST SOUNDINGS ON MONDAY KINDA CAUGHT ME BY SURPRISE. 18Z SOUNDINGS SHOW A BREAKABLE CAP AND CONVECTIVE TEMPS IN THE UPPER 80S. THE GFS IN PARTICULAR IS AGGRESSIVE WITH RAIN CHANCES AND GETS SOME SUPPORT FROM THE HI-RES ARW. THE LATEST RAP SHOWS A WEAK TROUGH AXIS ACROSS SE TX AT 16Z SO FEEL SOME PCPN SHOULD DEVELOP WITH FURTHER HEATING. ADDED VCSH FOR MON AFTN AND WILL WAIT FOR 00Z RUNS BEFORE EITHER ADDING THUNDER OR REMOVING PCPN ALL TOGETHER. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 72 94 74 95 74 / 20 10 10 10 10 HOUSTON (IAH) 73 93 75 94 75 / 20 20 10 10 10 GALVESTON (GLS) 81 87 80 88 80 / 30 20 10 20 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...44
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
622 PM CDT SUN JUN 9 2013 .DISCUSSION... SEE 00Z AVIATION DISCUSSION. && .AVIATION... CONDITIONS HAVE STABILIZED ACROSS SE TX AND AM EXPECTING THE CIRRUS SHIELD TO DISSIPATE IN THE NEXT HOUR OR SO. CONVECTION SHOULD REMAIN TO THE EAST AND TO THE WEST OF SE TX. AM A LITTLE CONCERNED ABOUT PATCHY FOG IN RURAL AREAS OVERNIGHT WITH GROUNDS REMAINING WET AND LIGHT WINDS. FCST SOUNDINGS ON MONDAY KINDA CAUGHT ME BY SURPRISE. 18Z SOUNDINGS SHOW A BREAKABLE CAP AND CONVECTIVE TEMPS IN THE UPPER 80S. THE GFS IN PARTICULAR IS AGGRESSIVE WITH RAIN CHANCES AND GETS SOME SUPPORT FROM THE HI-RES ARW. THE LATEST RAP SHOWS A WEAK TROUGH AXIS ACROSS SE TX AT 16Z SO FEEL SOME PCPN SHOULD DEVELOP WITH FURTHER HEATING. ADDED VCSH FOR MON AFTN AND WILL WAIT FOR 00Z RUNS BEFORE EITHER ADDING THUNDER OR REMOVING PCPN ALL TOGETHER. 43 && .PREV DISCUSSION... /ISSUED 348 PM CDT SUN JUN 9 2013/ DISCUSSION... PCPN CONTINUING TO WEAKEN/MOVE ON OUT OF THE AREA THIS AFTN. SKIES MAY TAKE A BIT LONGER TO CLEAR BUT THEY SHOULD EVENTUALLY TONIGHT. OTHERWISE RAIN CHANCES COULD HANG ON FOR ONE MORE DAY AS THE UPPER LEVEL TROF AXIS REMAINS OVER THE REGION (ALONG WITH ITS ASSOCIATED ELONGATED SHEAR AXIS). WE WILL HAVE PLENTY OF DAYTIME HEATING TOM- ORROW BUT THE AIRMASS THERE ARE STILL SOME QUESTIONS AS TO HOW UN- STABLE THE AIRMASS OVER SE TX WILL BE IN THE WAKE OF THIS ACTIVITY TODAY. BUILDING UPPER RIDGE WILL BE THE DOMINANT FEATURE FOR SE TX WX THE REST OF THE WEEK AS TEMPS CLIMB INTO THE MID/UPPER 90S. 41 MARINE... A LINE OF THUNDERSTORMS WILL CONTINUE TO PUSH THROUGH THE OFFSHORE WATERS WITH SOME GUSTY WINDS AND BRIEF HEAVY RAINFALL. STORMS SHOULD COME TO AN END LATER THIS EVENING AS A TROUGH AXIS PUSHES BY THE AREA. WINDS WILL BE GUSTY AND VARIABLE WITH THUNDERSTORMS IN THE AREA BUT EVENTUALLY RETURN TO THE SOUTH LATER TONIGHT INTO TOMORROW. LIGHT TO MODERATE SOUTHERLY WINDS ARE EXPECTED FOR MUCH OF THE COMING WEEK WITH GENERALLY LOW SEAS. 39 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 72 94 74 95 74 / 20 10 10 10 10 HOUSTON (IAH) 73 93 75 94 75 / 20 20 10 10 10 GALVESTON (GLS) 81 87 80 88 80 / 30 20 10 20 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...44 AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1246 PM CDT SAT JUN 8 2013 .DISCUSSION...UPDATED FOR 18Z AVIATION. && .AVIATION...A FEW SHOWERS AND STORMS REMAIN POSSIBLE IN THE EAST THIS AFTERNOON WITH INSTABILITY AND UPPER LEVEL ENERGY OVER THE AREA. THE BEST CHANCE WILL BE AROUND THE VCT AREA WHERE A FEW THUNDERSTORMS ARE POSSIBLE. TONIGHT EXPECT MVFR CIGS TO RETURN ACROSS ALL TAF SITES. WILL CONTINUE A SLIGHT CHANCE FOR SHOWERS AND STORMS TOMORROW...MAINLY FOR EASTERN TAF SITES. MAINLY SOUTHEAST WINDS AT MODERATE LEVELS WILL CONTINUE THROUGH THE PERIOD. && .PREV DISCUSSION... /ISSUED 641 AM CDT SAT JUN 8 2013/ DISCUSSION...SEE AVIATION BELOW FOR 12Z TAF UPDATE AVIATION...MVFR CEILINGS HAVE FILLED IN ACROSS KALI AND KCRP THIS MORNING. EXPECT CEILINGS TO DISSIPATE THROUGH THE MORNING. SHOWERS ARE POSSIBLE IN THE VICINITY OF ALL SITES LATER THIS MORNING THROUGH THE AFTERNOON. EXPECT LIGHT WINDS TO TURN TO EAST SOUTHEAST TODAY AND INCREASE TO A MODERATE FLOW IN EVENING AND OVERNIGHT. AT END OF THE PERIOD CLOUD COVER WILL BEGIN INCREASING AND SITES WILL REACH MVFR CONDITIONS AGAIN. PREV DISCUSSION... /ISSUED 415 AM CDT SAT JUN 8 2013/ SHORT TERM (TODAY AND TONIGHT)...A SERIES OF SHORTWAVES WILL MOVE THROUGH A WEAK MID/UPPER LVL TROUGH RESIDING OVER SOUTH TEXAS TODAY. COMBINED WITH AMPLE MOISTURE IN THE REGION /PWAT VALUES RANGING BETWEEN 1.6-1.8 INCHES/ EXPECT TO SEE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TODAY. FRONTAL BOUNDARY STALLED TO THE SOUTH SHOULD LIFT BACK TO THE NORTH OF THE REGION THIS MORNING. BOTH THE TEXAS TECH AND HRRR MODELS INDICATE CONVECTION DEVELOPING OFFSHORE LATER THIS MORNING AND MOVING INLAND...THOUGH HRRR KEEPS THE MAJORITY OF THIS CONVECTION OFFSHORE AND EARLIER IN THE MORNING. WENT WITH CHANCE POPS ACROSS MARINE AREAS AND COASTAL AND NORTHEAST ZONES. AS BOUNDARY MOVES TO THE NORTH THIS MORNING WINDS WILL GENERALLY RETURN TO A WEAK TO MODERATE ONSHORE FLOW. TEMPERATURES WILL REMAIN NEAR NORMAL TODAY. LONG TERM (SUNDAY THROUGH FRIDAY)...TAIL END OF MID AND UPPER LEVEL TROUGH WILL EXTEND BACK INTO SOUTH TEXAS ON SUNDAY...AND WILL BE RESPONSIBLE FOR ISOLATED SHOWERS AND THUNDERSTORMS DURING THE DAY ACROSS THE EASTERN CWA. ON MONDAY RIDGING BEGINS TO BUILD OUT OF MEXICO INTO THE WESTERN HALF OF THE STATE. THE TAIL END OF THE TROUGH ON SUNDAY WILL LEAVE A WEAKNESS BEHIND MONDAY OVER THE GULF WATERS AND COASTAL BEND ALONG WITH POOL OF HIGHER MOISTURE. COULD BE A FEW SHOWERS AND POSSIBLY THUNDERSTORMS ACROSS THIS REGION. TUESDAY THROUGH THURSDAY THE MID AND UPPER LEVEL RIDGE WILL BUILD INTO NORTH AND CENTRAL TEXAS...AND BENEATH IT THE AFOREMENTIONED WEAKNESS DEVELOPS INTO A BROAD INVERTED TROUGH ACROSS SOUTH TEXAS AND NORTHERN MEXICO. DEEPER MOISTURE ORIGINATING FROM THE BAY OF CAMPECHE ALSO WORKS NORTHWESTWARD TOWARDS THE REGION. THE DEEPEST MOISTURE WILL BE JUST SOUTH OF THE AREA...BUT HIGH ENOUGH VALUES AND MARGINAL MID LEVELS TEMPS ACROSS THE CRP CWA TO SUPPORT 10-20 POPS FOR ISOLATED SHOWERS AND THUNDERSTORMS TUESDAY THROUGH THURSDAY... PRIMARILY OVER THE GULF DURING THE OVERNIGHT AND MORNING HOURS...OVER THE COASTAL BEND DURING THE MORNING AND EARLY AFTERNOON...AND SHIFTING INLAND INTO THE BRUSH COUNTRY AND RIO GRANDE PLAINS EACH AFTERNOON AND EARLY EVENING. TEMPERATURES NEAR NORMAL OUT WEST AND SLIGHTLY ABOVE NORMAL ACROSS THE EAST. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 78 95 79 96 78 / 10 20 10 20 10 VICTORIA 75 91 75 92 76 / 10 20 10 20 10 LAREDO 78 98 75 96 75 / 10 10 10 10 10 ALICE 75 96 76 96 75 / 10 20 10 20 10 ROCKPORT 80 91 80 91 78 / 10 20 10 20 10 COTULLA 76 99 75 98 75 / 10 10 10 10 10 KINGSVILLE 77 95 76 95 76 / 10 20 10 20 10 NAVY CORPUS 79 90 79 90 79 / 10 20 10 20 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ PZ/83...AVIATION
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1236 PM CDT SAT JUN 8 2013 .DISCUSSION... 18Z TAF DISCUSSION. && .AVIATION... REALLY TOUGH DECISION ON THE DEVELOPMENT OF TSRA LATER THIS AFTERNOON. THINK WITH MOISTURE SLOWLY INCREASING AND CONVECTION FORMING TO THE SW OF MOST TERMINALS...WILL GO AHEAD WITH VCTS WORDING FOR TAFS KIAH SOUTHWARD. WILL KEEP CONVECTION OUT OF KCXO/KUTS/KCLL TAFS. GFS SEEMS TO BE ONLY MODEL HANDLING CURRENT CONVECTION WELL WITH 15Z HRRR NOT TOO BAD. GET A 20KT LLJ BACK TONIGHT SO MAY SEE SOME LOW STRATOCU DECK FORM BUT WILL KEEP VFR CIGS FOR NOW. TOMORROW MORNING LOOKING MORE INTERESTING AS GFS HINTS AT ANOTHER ROUND OF CONVECTION. SHORTWAVE TROUGH NOW OVER OK/TX PANHANDLE MAY BE INITIATING CONVECTION LATE MORNING HOURS TOMORROW. WENT WITH VCTS AGAIN TO HINT AT THUNDERSTORM POSSIBILITIES. 39 && .PREV DISCUSSION... /ISSUED 1137 AM CDT SAT JUN 8 2013/ DISCUSSION... MADE SOME TWEAKS TO THE GOING FCST...MAINLY TO ACCOUNT FOR THE ONGOING PCPN TRENDS ALONG THE COAST (IN PROXIMITY TO THE UPPER LEVEL LOW). HAVE RAISED POPS A BIT FOR THESE LOCATIONS FOR THE REST OF THE AFTN. WILL ALSO HAVE TO KEEP AN EYE OUT ON LOCALLY HEAVY RAINS GIVEN THE VERY SLOW MOVEMENT OF THIS ACTIVITY. 41 PREV DISCUSSION... /ISSUED 414 AM CDT SAT JUN 8 2013/ A SLOW MOVING MID/UPPER LEVEL DISTURBANCE ACROSS THE AREA CONTINUES TO PRODUCE AREAS OF LIGHT RAIN AND SHOWERS WITH OCCASIONAL EMBEDDED THUNDERSTORMS TO LOCATIONS GENERALLY SOUTH OF A LINE FROM WHARTON TO THE ANGLETON AREA TO HIGH ISLAND. HAVE SLIGHT CHANCE TO CHANCE POPS FOR TODAY WITH THE HIGHER NUMBERS NEAR THE COAST AND OFFSHORE. WILL KEEP SOME RAIN CHANCES IN THE FORECAST FOR THE END OF THE WEEKEND AND ON INTO THE FIRST FEW DAYS OF THE UPCOMING WEEK AS THE AREA BECOMES POSITIONED ON THE SOUTHERN FRINGES OF A BUILDING MID/UPPER LEVEL RIDGE. IF THE MODELS ARE CORRECT IN BUILDING THE RIDGE INTO OUR AREA TOWARD THE END OF THE WEEK AND ON INTO NEXT WEEKEND...SOUTHEAST TEXAS WILL END UP DRY AND WARMER WITH SOME INLAND HIGH TEMPERATURES POSSIBLY APPROACHING THE UPPER 90S. ON AVERAGE...THE DATE THAT CLL REACHES 100 DEGREES IS JULY 15TH...AND FOR IAH IS JULY 18TH. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 90 71 91 73 93 / 10 10 20 10 20 HOUSTON (IAH) 91 72 92 74 93 / 20 10 20 10 20 GALVESTON (GLS) 86 77 87 79 89 / 30 10 20 10 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...41 AVIATION/MARINE...39
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
641 AM CDT SAT JUN 8 2013 .DISCUSSION...SEE AVIATION BELOW FOR 12Z TAF UPDATE && .AVIATION...MVFR CEILINGS HAVE FILLED IN ACROSS KALI AND KCRP THIS MORNING. EXPECT CEILINGS TO DISSIPATE THROUGH THE MORNING. SHOWERS ARE POSSIBLE IN THE VICINITY OF ALL SITES LATER THIS MORNING THROUGH THE AFTERNOON. EXPECT LIGHT WINDS TO TURN TO EAST SOUTHEAST TODAY AND INCREASE TO A MODERATE FLOW IN EVENING AND OVERNIGHT. AT END OF THE PERIOD CLOUD COVER WILL BEGIN INCREASING AND SITES WILL REACH MVFR CONDITIONS AGAIN. && .PREV DISCUSSION... /ISSUED 415 AM CDT SAT JUN 8 2013/ SHORT TERM (TODAY AND TONIGHT)...A SERIES OF SHORTWAVES WILL MOVE THROUGH A WEAK MID/UPPER LVL TROUGH RESIDING OVER SOUTH TEXAS TODAY. COMBINED WITH AMPLE MOISTURE IN THE REGION /PWAT VALUES RANGING BETWEEN 1.6-1.8 INCHES/ EXPECT TO SEE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TODAY. FRONTAL BOUNDARY STALLED TO THE SOUTH SHOULD LIFT BACK TO THE NORTH OF THE REGION THIS MORNING. BOTH THE TEXAS TECH AND HRRR MODELS INDICATE CONVECTION DEVELOPING OFFSHORE LATER THIS MORNING AND MOVING INLAND...THOUGH HRRR KEEPS THE MAJORITY OF THIS CONVECTION OFFSHORE AND EARLIER IN THE MORNING. WENT WITH CHANCE POPS ACROSS MARINE AREAS AND COASTAL AND NORTHEAST ZONES. AS BOUNDARY MOVES TO THE NORTH THIS MORNING WINDS WILL GENERALLY RETURN TO A WEAK TO MODERATE ONSHORE FLOW. TEMPERATURES WILL REMAIN NEAR NORMAL TODAY. LONG TERM (SUNDAY THROUGH FRIDAY)...TAIL END OF MID AND UPPER LEVEL TROUGH WILL EXTEND BACK INTO SOUTH TEXAS ON SUNDAY...AND WILL BE RESPONSIBLE FOR ISOLATED SHOWERS AND THUNDERSTORMS DURING THE DAY ACROSS THE EASTERN CWA. ON MONDAY RIDGING BEGINS TO BUILD OUT OF MEXICO INTO THE WESTERN HALF OF THE STATE. THE TAIL END OF THE TROUGH ON SUNDAY WILL LEAVE A WEAKNESS BEHIND MONDAY OVER THE GULF WATERS AND COASTAL BEND ALONG WITH POOL OF HIGHER MOISTURE. COULD BE A FEW SHOWERS AND POSSIBLY THUNDERSTORMS ACROSS THIS REGION. TUESDAY THROUGH THURSDAY THE MID AND UPPER LEVEL RIDGE WILL BUILD INTO NORTH AND CENTRAL TEXAS...AND BENEATH IT THE AFOREMENTIONED WEAKNESS DEVELOPS INTO A BROAD INVERTED TROUGH ACROSS SOUTH TEXAS AND NORTHERN MEXICO. DEEPER MOISTURE ORIGINATING FROM THE BAY OF CAMPECHE ALSO WORKS NORTHWESTWARD TOWARDS THE REGION. THE DEEPEST MOISTURE WILL BE JUST SOUTH OF THE AREA...BUT HIGH ENOUGH VALUES AND MARGINAL MID LEVELS TEMPS ACROSS THE CRP CWA TO SUPPORT 10-20 POPS FOR ISOLATED SHOWERS AND THUNDERSTORMS TUESDAY THROUGH THURSDAY... PRIMARILY OVER THE GULF DURING THE OVERNIGHT AND MORNING HOURS...OVER THE COASTAL BEND DURING THE MORNING AND EARLY AFTERNOON...AND SHIFTING INLAND INTO THE BRUSH COUNTRY AND RIO GRANDE PLAINS EACH AFTERNOON AND EARLY EVENING. TEMPERATURES NEAR NORMAL OUT WEST AND SLIGHTLY ABOVE NORMAL ACROSS THE EAST. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 90 78 95 79 96 / 30 10 20 10 20 VICTORIA 90 75 91 75 92 / 30 10 20 10 20 LAREDO 96 78 98 75 96 / 20 10 10 10 10 ALICE 91 75 96 76 96 / 30 10 20 10 20 ROCKPORT 83 80 91 80 91 / 30 10 20 10 20 COTULLA 95 76 99 75 98 / 20 10 10 10 10 KINGSVILLE 89 77 95 76 95 / 30 10 20 10 20 NAVY CORPUS 84 79 90 79 90 / 30 10 20 10 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ LK/84...AVIATION
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
415 AM CDT SAT JUN 8 2013 .SHORT TERM (TODAY AND TONIGHT)...A SERIES OF SHORTWAVES WILL MOVE THROUGH A WEAK MID/UPPER LVL TROUGH RESIDING OVER SOUTH TEXAS TODAY. COMBINED WITH AMPLE MOISTURE IN THE REGION /PWAT VALUES RANGING BETWEEN 1.6-1.8 INCHES/ EXPECT TO SEE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TODAY. FRONTAL BOUNDARY STALLED TO THE SOUTH SHOULD LIFT BACK TO THE NORTH OF THE REGION THIS MORNING. BOTH THE TEXAS TECH AND HRRR MODELS INDICATE CONVECTION DEVELOPING OFFSHORE LATER THIS MORNING AND MOVING INLAND...THOUGH HRRR KEEPS THE MAJORITY OF THIS CONVECTION OFFSHORE AND EARLIER IN THE MORNING. WENT WITH CHANCE POPS ACROSS MARINE AREAS AND COASTAL AND NORTHEAST ZONES. AS BOUNDARY MOVES TO THE NORTH THIS MORNING WINDS WILL GENERALLY RETURN TO A WEAK TO MODERATE ONSHORE FLOW. TEMPERATURES WILL REMAIN NEAR NORMAL TODAY. && .LONG TERM (SUNDAY THROUGH FRIDAY)...TAIL END OF MID AND UPPER LEVEL TROUGH WILL EXTEND BACK INTO SOUTH TEXAS ON SUNDAY...AND WILL BE RESPONSIBLE FOR ISOLATED SHOWERS AND THUNDERSTORMS DURING THE DAY ACROSS THE EASTERN CWA. ON MONDAY RIDGING BEGINS TO BUILD OUT OF MEXICO INTO THE WESTERN HALF OF THE STATE. THE TAIL END OF THE TROUGH ON SUNDAY WILL LEAVE A WEAKNESS BEHIND MONDAY OVER THE GULF WATERS AND COASTAL BEND ALONG WITH POOL OF HIGHER MOISTURE. COULD BE A FEW SHOWERS AND POSSIBLY THUNDERSTORMS ACROSS THIS REGION. TUESDAY THROUGH THURSDAY THE MID AND UPPER LEVEL RIDGE WILL BUILD INTO NORTH AND CENTRAL TEXAS...AND BENEATH IT THE AFOREMENTIONED WEAKNESS DEVELOPS INTO A BROAD INVERTED TROUGH ACROSS SOUTH TEXAS AND NORTHERN MEXICO. DEEPER MOISTURE ORIGINATING FROM THE BAY OF CAMPECHE ALSO WORKS NORTHWESTWARD TOWARDS THE REGION. THE DEEPEST MOISTURE WILL BE JUST SOUTH OF THE AREA...BUT HIGH ENOUGH VALUES AND MARGINAL MID LEVELS TEMPS ACROSS THE CRP CWA TO SUPPORT 10-20 POPS FOR ISOLATED SHOWERS AND THUNDERSTORMS TUESDAY THROUGH THURSDAY... PRIMARILY OVER THE GULF DURING THE OVERNIGHT AND MORNING HOURS...OVER THE COASTAL BEND DURING THE MORNING AND EARLY AFTERNOON...AND SHIFTING INLAND INTO THE BRUSH COUNTRY AND RIO GRANDE PLAINS EACH AFTERNOON AND EARLY EVENING. TEMPERATURES NEAR NORMAL OUT WEST AND SLIGHTLY ABOVE NORMAL ACROSS THE EAST. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 90 78 95 79 96 / 30 10 20 10 20 VICTORIA 90 75 91 75 92 / 30 10 20 10 20 LAREDO 96 78 98 75 96 / 20 10 10 10 10 ALICE 91 75 96 76 96 / 30 10 20 10 20 ROCKPORT 83 80 91 80 91 / 30 10 20 10 20 COTULLA 95 76 99 75 98 / 20 10 10 10 10 KINGSVILLE 89 77 95 76 95 / 30 10 20 10 20 NAVY CORPUS 84 79 90 79 90 / 30 10 20 10 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ LK/84...SHORT TERM JR/76...LONG TERM
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1127 PM CDT FRI JUN 7 2013 .DISCUSSION... SEE THE 06Z AVIATION DISCUSSION BELOW. && .AVIATION... CONVECTION ACROSS THE HIGH PLAINS CONTINUES TO MOVE IN A GENERAL SOUTHEASTERLY DIRECTION WITH AN ASSOCIATED CIRRUS CANOPY ALREADY ADVECTING ACROSS WEST CENTRAL TX. THE LATEST MODEL DATA INDICATES THAT THIS ACTIVITY WILL CONTINUE TO WEAKEN AS IT MOVES INTO AN AREA OF GREATER STABILITY. LITTLE TO NO IMPACT IS ANTICIPATED AT ANY OF THE TERMINALS OVERNIGHT. WE WILL...HOWEVER..SEE A LOT OF MID/HIGH CLOUD COVER THROUGH THE FIRST 12-18 HRS OF THE TAF PERIOD. THESE CLOUDS WILL GIVE WAY TO SOME AFTERNOON CU GENERALLY ABOVE 5 KFT SATURDAY AFTERNOON. A FEW SHOWERS AND/OR THUNDERSTORMS CANNOT BE RULED OUT SATURDAY AFTERNOON/EVENING BUT IF ANYTHING DEVELOPS IT SHOULD BE VERY ISOLATED. OTHERWISE...EXPECT LIGHT SOUTHEAST WINDS VEERING TO THE SOUTH BY 15Z AND INCREASING TO 12-15 KTS BY MIDDAY. GUSTS MAY EXCEED 20 KTS...ESPECIALLY AT KSJT AND KABI. JOHNSON && .PREV DISCUSSION... /ISSUED 632 PM CDT FRI JUN 7 2013/ DISCUSSION... SEE THE 00Z AVIATION DISCUSSION BELOW. AVIATION... MID/HIGH CLOUDS CONTINUE TO MOVE OFF TO THE EAST OF THE FORECAST TERMINALS LEAVING MOSTLY CLEAR SKIES ACROSS WEST CENTRAL TX. HOWEVER...CONVECTION ACROSS THE TX PANHANDLE AND EASTERN NM WILL MOVE SOUTH SOUTHEAST OVERNIGHT OVERSPREAD MID/HIGH LEVEL DEBRIS ACROSS THE AREA. SOME OF THIS ACTIVITY MAY MAKE IT INTO THE FORECAST AREA BUT CONFIDENCE IS LOW THAT IT WILL HOLD TOGETHER. IF IT DOES INDEED REMAIN INTACT...THE TIMING WILL BE AROUND 12... FAVORING THE KABI OR KSJT TERMINALS. AT THIS TIME...THE FORECAST REMAINS DRY. LIGHT SOUTHEAST WINDS ARE ANTICIPATED OVERNIGHT... BECOMING SOUTHERLY AT 12-15 KTS /WITH GUSTS OVER 20 KTS AT TIMES/ BY EARLY AFTERNOON. JOHNSON PREV DISCUSSION... /ISSUED 355 PM CDT FRI JUN 7 2013/ SHORT TERM... .THROUGH SATURDAY... FOCUS IN THE SHORT TERM PERIOD WILL BE CONVECTIVE POTENTIAL AGAIN LATE TONIGHT INTO SATURDAY MORNING. THUNDERSTORMS ARE BEGINNING TO DEVELOP OVER THE MOUNTAINS OF NEW MEXICO THIS AFTERNOON IN RESPONSE TO AN EMBEDDED SHORTWAVE MOVING SOUTHEAST ACROSS COLORADO. LATEST HRRR SHOWS THIS ACTIVITY DEVELOPING INTO A COMPLEX LATER TONIGHT...ENTERING WESTERN SECTIONS OF THE CONCHO VALLEY AND THE NORTH EDWARDS PLATEAU AROUND 4 AM. THE GFS ALSO SHOWS THIS SCENARIO WHILE THE NAM DISSIPATES ACTIVITY JUST WEST OF THE AREA. WILL SIDE WITH THE HRRR AND GFS AS CONVECTION SHOULD SUSTAIN ITSELF GIVEN THE SHORT WAVE AND A STRENGTHENING NOCTURNAL JET THAT DEVELOPS ACROSS WEST TEXAS LATER THIS EVENING. WENT WITH 20 TO 30 POPS ACROSS ROUGHLY THE WESTERN HALF OF THE CWA AFTER MIDNIGHT WITH HIGHEST POPS ACROSS THE CONCHO VALLEY AND NORTH EDWARDS PLATEAU. NO SEVERE WEATHER IS EXPECTED BUT SOME OF THE STORMS WILL BE CAPABLE OF GUSTY WINDS AND BRIEF HEAVY RAINFALL. ACTIVITY WILL WEAKEN ACROSS THE AREA DURING THE MORNING HOURS WITH DRY CONDITIONS EXPECTED FOR SATURDAY AFTERNOON. LOWS TONIGHT WILL BE IN THE 60S WITH HIGHS SATURDAY IN THE LOWER 90S. LONG TERM... THE MEDIUM RANGE MODELS INDICATE AN MCS DEVELOPING ACROSS KANSAS SATURDAY EVENING...THEN MOVING SOUTHEAST ACROSS OKLAHOMA...WEAKENING OVER NORTH TEXAS SUNDAY MORNING. LOOKS LIKE MOST OF THE ACTIVITY WILL REMAIN NORTH AND EAST OF OUR CWFA. HOWEVER...WILL KEEP THE SLGT CHC POPS GOING ACROSS THE NORTHERN BIG COUNTRY SATURDAY NIGHT. VERY WARM TEMPERATURES FOR SUNDAY WITH HIGHS IN THE MID 90S. MONDAY THROUGH FRIDAY...AN UPPER LEVEL HIGH PRESSURE RIDGE WILL BUILD ACROSS TEXAS NEXT WEEK. THIS MEANS A HOT AND DRY FORECAST. HIGHS WILL BE IN THE MID 90S TO AROUND 100 MONDAY AND TUESDAY...WARMING TO THE UPPER 90S TO AROUND 105 WEDNESDAY THROUGH FRIDAY. LOWS WILL BE IN THE 70S. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 63 89 72 93 74 / 20 20 10 5 5 SAN ANGELO 62 92 72 96 74 / 30 20 5 5 5 JUNCTION 62 91 70 93 73 / 10 10 5 5 5 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 25
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
829 PM CDT SUN JUN 9 2013 .UPDATE...500MB SHORTWAVE TROUGH SLIDING SOUTHEASTWARD ACROSS IOWA TOWARD WEST CENTRAL ILLINOIS. SHOWERS WITH ISOLATED STORMS ASSOCIATED WITH DIFFERENTIAL CYCLONIC VORTICITY ADVECTION WITHIN SHORTWAVE TROUGH WERE SHIFTING NORTH NORTHWESTWARD ACROSS MAINLY SOUTH CENTRAL WISCONSIN. MORE SHOWERS WERE MOVING NORTHWARD TOWARD THE FORECAST AREA FROM NORTHERN ILLINOIS. SHORTWAVE TROUGH IS EXPECTED TO CONTINUE TO SHIFT SOUTHEASTWARD INTO NORTH CENTRAL ILLINOIS LATER TONIGHT...THEN CONTINUE EAST ON MONDAY. MESOSCALE MODELS WERE SHOWING THE SHOWER ACTIVITY WITH THIS FEATURE PIVOTING OVER THE FORECAST AREA LATER TONIGHT...MAINLY IN THE SOUTHERN TWO THIRDS OF THE AREA. AREA FORECAST SOUNDINGS FROM RAP LOSE WEAK INSTABILITY DURING THIS TIME...WITH NAM HOLDING ONTO IT. GIVEN CURRENT TRENDS...WILL LEAVE OUT THUNDER MENTION LATER TONIGHT. SOME BREAKS ARE EXPECTED WITHIN THE SHOWERS...SO WILL HAVE POPS AT LEAST IN THE SCATTERED TO NUMEROUS RANGE AS THEY PIVOT ACROSS THE AREA LATER TONIGHT INTO MONDAY. THE SHOWERS WOULD THEN SHIFT OFF TO THE EAST MONDAY...WITH A FEW SHOWERS STILL POSSIBLE LATER IN THE DAY WITH WEAK INSTABILITY AND MOISTURE REMAINING. LINGERING LOW LEVEL MOISTURE/LOW CEILINGS AND WEAKENING WINDS LATER TONIGHT INTO EARLY MONDAY MORNING SUGGEST AREAS OF FOG DEVELOPMENT WILL OCCUR. FOR NOW...DO NOT THINK THERE WILL BE DENSE FOG...WITH THE LOW CLOUDS EXPECTED. LOWS AT LEAST IN THE MID TO UPPER 50S ARE EXPECTED...WITH CLOUDS AND PRECIPITATION IN THE AREA. && .AVIATION/06Z TAFS/...TROUGH OF LOW PRESSURE WILL PASS SOUTHWEST OF THE AREA LATER TONIGHT...THEN SHIFT EAST ON MONDAY. SHOWERS WILL AFFECT TAF SITES ON AND OFF TONIGHT...LINGERING INTO MONDAY MORNING BEFORE MOVING OFF TO THE EAST. MAY SEE A FEW SHOWERS DEVELOP LATER MONDAY AFTERNOON IF CLOUDS MIX OUT AND TEMPERATURES WARM UP. CEILINGS AND VISIBILITIES SHOULD DROP INTO THE MVFR TO IFR RANGE AFTER 06Z MONDAY INTO MOST OF MONDAY MORNING...AS LOW LEVEL MOISTURE INCREASES AND WINDS WEAKEN. VISIBILITIES DOWN TO AROUND ALTERNATE MINIMUMS ARE EXPECTED...AND COULD GET A BIT LOWER. NOT EXPECTING DENSE FOG AT THIS TIME...BUT WILL HAVE TO WATCH TRENDS. CEILINGS SHOULD DROP TO NEAR THESE LEVELS AS WELL. CEILINGS AND VISIBILITIES SHOULD IMPROVE TO MVFR LEVELS BY 17Z MONDAY...THEN TO VFR LEVELS BY 21Z MONDAY. CEILINGS MAY MIX OUT AT MADISON DURING MID TO LATE AFTERNOON...AND SHOULD MIX OUT MONDAY EVENING AT ALL SITES. && .MARINE...DEW POINTS IN THE MID 50S OVER COLDER LAKE WATERS IN THE MID 40S TO AROUND 50 WITH WEAKENING WINDS SHOULD RESULT IN AREAS OF FOG DEVELOPING ACROSS THE NEARSHORE WATERS LATER TONIGHT INTO MONDAY. DENSE FOG IS A POSSIBILITY...AS VISIBILITIES OF ONLY 1 MILE OR LESS ARE NEEDED OVER THE WATERS. ADDED AREAS OF FOG FOR LATER TONIGHT INTO EARLY MONDAY...AND MAY NEED TO ADD PATCHY DENSE FOG. WILL HAVE TO MONITOR TRENDS WITH DENSE FOG LATER TONIGHT INTO MONDAY. && .PREV DISCUSSION... /ISSUED 233 PM CDT SUN JUN 9 2013/ TONIGHT - CONFIDENCE...MEDIUM INFLUENCE OF UPPER LOW WILL DRAW CLOSER BRINGING INCREASING CHANCES OF SHRA. ALREADY SEEING EVIDENCE OF THIS IN FAR WESTERN WI WITH A BAND OF SHRA LIFTING NORTH WITH A SLOW DRIFT TO THE EAST. PROGS GRADUALLY SHIFT QPF ACROSS THE CWA...AND THIS MAKES SENSE GIVEN THE VERY SLOW MOVEMENT OF THE SYSTEM IN IOWA. INCREASING LOW LEVEL MOISTURE WILL LEAD TO PATCHY FOG DEVELOPMENT WITH SOME GUIDANCE INDICATING A GOOD DEAL OF STRATUS LATER IN THE NIGHT. BELIEVE THUNDER IN IOWA HELPED ALONG BY DIURNALLY DRIVEN INSTABILITY. NAM SOUNDINGS STILL SHOWING A FEW HUNDRED J/KG OF ELEVATED CAPE AS THE NIGHT WEARS ON SO WILL LEAVE A BIT OF THUNDER IN THE GRIDS MAINLY FOR WESTERN/CENTRAL CWA. MONDAY - CONFIDENCE...MEDIUM BROAD CIRCULATION IN CENTRAL ILLINOIS WILL SHIFT TO OHIO. PLENTY OF LOW LEVEL RH PROGGD TO LINGER SO EXPECT TO BE BATTLING A GOOD DEAL OF CLOUDS AND SPOTTY LIGHT PRECIP FROM THE OUTSET. SOME DRIER AIR AND NVA KICKS IN DURING THE AFTERNOON. HOWEVER MOS GUID AND LOW LEVEL RH PROGS QUITE SLOW TO SCOUR THINGS OUT. NAM SOUNDINGS SHOW MUCH MORE DRIER/MIXED PROFILE IN THE LOW LEVELS WHILE THE GFS HAS MORE 900 MILLIBAR MOISTURE WITH AN INVERSION. GIVEN EXTENSIVE AMOUNT OF MOISTURE/CLOUD COVER WRAPPED UP IN THIS SYSTEM THINK THE MORE PESSIMISTIC SOUNDINGS FIT BETTER AT THIS POINT. MONDAY NIGHT AND TUESDAY...FORECAST CONFIDENCE IS HIGH. WE SHOULD SEE THE PRECIP EXIT THE AREA BY MONDAY EVENING WITH WEAK HIGH PRESSURE BUILDING IN FOR A BRIEF TIME. 925MB TEMPS WARM UP NICELY FOR TUESDAY...REACHING 21-23C BY LATE AFTERNOON. COUPLE THIS WITH A LITTLE SUNSHINE...AT LEAST FOR THE FIRST HALF OF THE DAY...AND WE SHOULD SEE HIGHS CLIMB INTO THE LOWER AND MID 80S...THOUGH A BIT COOLER NEAR LAKE MICHIGAN. TUESDAY NIGHT INTO WEDNESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM. LOW PRESSURE WILL PASS SOUTH OF WISCONSIN DURING THIS PERIOD WITH AN ASSOCIATED WARM FRONT ALSO SETTING UP JUST SOUTH OF THE STATE. THIS IS A DECENT SCENARIO FOR RAIN ACROSS SOUTHERN WISCONSIN. THE LOW LEVEL JET WILL BE PUMPING MOISTURE AND WARM AIR INTO THE FRONTAL ZONE AND THERE APPEARS TO BE GOOD DIVERGENCE IN THE RIGHT REAR ENTRANCE REGION OF THE UPPER JET. THE MODELS ARE HAVING TIMING/LOCATION ISSUES WITH THE SERIES OF MID LEVEL SHORT WAVES EXPECTED TO ROLL SOUTHEAST ACROSS THIS AREA DURING THE PERIOD. THE BULK OF THE PRECIP SHOULD MOSTLY BE SOUTH OF I-94...BUT CAN/T RULE IT OUT FARTHER NORTH. IT LOOKS LIKE THE BEST CHANCE FOR STORMS...POSSIBLY AND MCS...WOULD BE LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. THE SEVERE THREAT LOOKS TO BE FARTHER TO THE SOUTH...OUT OF WISCONSIN...CLOSER TO THE WARM FRONT. THURSDAY AND FRIDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH. THINGS ARE LOOKING PRETTY NICE THIS PERIOD AS HIGH PRESSURE BUILDS IN. TEMPS CLOSE TO NORMAL FOR THIS TIME OF YEAR. SATURDAY AND SUNDAY...FORECAST CONFIDENCE MEDIUM. THE GFS AND THE ECMWF BOTH SHOW A MID LEVEL TROF RIDING OVER THE TOP OF THE RIDGE...DROPPING THROUGH WISCONSIN. THEY BOTH DEVELOP SOME PRECIP WITH IT THAT ROLLS IN ON SATURDAY. SUNDAY IS QUESTIONABLE...AS THE GFS DEVELOPS MORE PRECIP WHILE THE EC IS DRY. AVIATION/00Z TAFS/...MID/HIGH LEVEL MOISTURE CONTINUES TO PIVOT NORTHWARD AHEAD OF THE LOW PRESSURE CENTER IN NW IA. BAND OF SHRA LIFTING NORTH ALONG AND JUST EAST OF MISS RIVER. LOW PROGGD TO MOVE INTO CNTRL IL TNGT AND INTO OHIO MONDAY. DURING THIS TIME SOME SHRA/ISOLD TSRA POTENTIAL INCREASES AS SRN WI BECOMES BETTER SITUATED IN THE MOISTURE/LIFT ZONE OF THIS FEATURE AS IT SHIFTS ESE FROM IOWA. WILL BRING IN SOME LOWER CEILINGS TOO AS THESE ARE MOST WIDESPREAD UPSTREAM IN IOWA/MN. SOME COVERAGE OF IFR CIGS AS WELL LATER TNGT INTO MONDAY MORNING PER SREF CEILING PROBS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...WOOD TONIGHT/MONDAY AND AVIATION/MARINE...COLLAR MONDAY NIGHT THROUGH SUNDAY...DAVIS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
640 PM CDT SUN JUN 9 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 250 PM CDT SUN JUN 9 2013 CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED TROUGHING OVER SOUTHWEST CANADA...AN UPPER LOW OFF THE COAST OF SOUTHERN CALIFORNIA...RIDGING OVER THE DESERT SOUTHWEST...AN UPPER TROUGH FROM MINNESOTA SOUTH TO MISSOURI...AND RIDGING OVER THE GREAT LAKES. WITHIN THE UPPER TROUGH APPROACHING THE MISSISSIPPI RIVER VALLEY...AN UPPER LOW WAS SITUATED IN NORTHWEST IA WITH 500MB STANDARDIZED DEVIATIONS OF 1.5 BELOW NORMAL. MAIN SURGE OF WARM ADVECTION INDUCED PRECIPITATION AHEAD OF THIS TROUGH...WHICH MOVED NORTH THROUGH THE FORECAST AREA LAST NIGHT AND THIS MORNING...HAS LIFTED INTO NORTHERN MN AND WESTERN UPPER MI. ADDITIONAL SHOWERS AND EMBEDDED THUNDERSTORMS HAVE FIRED IMMEDIATELY AHEAD OF THE UPPER LOW OVER EASTERN IOWA...SOUTHERN MN AND WESTERN WI. THESE ARE A RESULT OF COOL AIR ALOFT UNDER THE UPPER TROUGH ALLOWING FOR SURFACE BASED CAPES OF 500-1000 J/KG GIVEN TEMPERATURES OF 65-75F AND DEWPOINTS IN THE LOWER 60S. ADDITIONALLY...A COLD FRONT EXTENDING FROM LOW PRESSURE IN NORTHWEST IA AT THE SURFACE HAS PROVIDED A FOCUSED AREA OF LOW LEVEL CONVERGENCE. CLOUDS ARE WIDESPREAD OVER THE REGION WITH THE MAIN CLEARING LINE TO THE WEST OVER THE EASTERN DAKOTAS. MODELS ARE IN VERY GOOD AGREEMENT IN PUSHING THE UPPER LOW SOUTHEASTWARD...TRACKING IT INTO CENTRAL ILLINOIS BY 12Z MONDAY AND WESTERN OHIO BY 00Z TUESDAY. THE UPPER LOW APPEARS TO BE PUSHED BY AN UPPER JET STREAK OVER SOUTHWEST CANADA HEADING TO THE EAST. THIS MEANS THE DRYING AND CLEARING TAKING PLACE OVER THE WESTERN DAKOTAS WILL EVENTUALLY GET HERE. TIMING IS IMPORTANT...THOUGH...BECAUSE IF THE CLEARING MOVES INTO THE FORECAST AREA DURING THE NIGHT...THE RECENT RAINS WILL FAVOR FOG AND POSSIBLE DENSE FOG DEVELOPMENT. VARIOUS MODEL 700MB AND 500MB RH FIELDS SUGGEST THESE WILL DRY OUT WEST OF THE MISSISSIPPI RIVER AFTER MIDNIGHT...BUT 925-850MB RH FIELDS STAY PRETTY MOIST TO FULLY SATURATED ALL THE WAY WEST TO SAY FARMINGTON MN AT 12Z MONDAY. THUS...CONFIDENCE ON A RADIATION FOG EVENT IS VERY LOW. HIRES ARW VISIBILITY FORECASTS SUGGEST THE BULK OF THE FOG ENDS UP OVER WESTERN PORTIONS OF MN AND IA AS WELL AS OVER EASTERN WI...LEAVING OUR AREA MAYBE WITH SOME PATCHY/AREAS OF FOG AT BEST. HAVE FOLLOWED THIS IDEA WITH THE THOUGHT OF LOW STRATUS IN PLACE TONIGHT. BETTER SHOT FOR CLEARING SHOULD COME DURING THE DAY MONDAY...SPREADING WEST TO EAST...AS THE UPPER LOW MOVES FARTHER AWAY AND DAYTIME MIXING CAN GET RID OF THE CLOUDS. REGARDING PRECIPITATION...ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS WILL LIKELY PERSIST AND SLOWLY PUSH EAST THROUGH THE EARLY EVENING HOURS. AS INSTABILITY WANES WITH LOSS OF DAYTIME HEATING...EXPECTING THE SHOWERS TO DIMINISH...ESPECIALLY AFTER 03Z. BY 12Z MOST IF NOT ALL OF THE FORECAST AREA SHOULD BE DRY. ON MONDAY...AN INVERTED SURFACE TROUGH EXTENDING FROM THE LOW PASSING BY TO OUR SOUTH IS PROGGED TO LAY UP OVER CENTRAL AND EASTERN WI. WEAK INSTABILITY WITH MUCAPE UP TO 500 J/KG PLUS CONVERGENCE ALONG THIS TROUGH MAY YIELD SOME SHOWER DEVELOPMENT. THUS...HAVE KEPT 20-30 PERCENT CHANCES GOING...MAINLY AFTER 15Z AND OVER CENTRAL WI. NON-SUPERCELL TORNADO PARAMETER WOULD FOCUS THE POTENTIAL FOR THEM OVER SOUTHEAST WI...AWAY FROM OUR FORECAST AREA. FOR TEMPERATURES...PLENTY OF CLOUDS TONIGHT WITH LITTLE IN THE WAY OF WIND SHOULD ALLOW FOR JUST A VERY SLOW DROP. A BLEND OF MOS GUIDANCE SEEMS REASONABLE IN THIS SITUATION...RESULTING IN LOWS IN THE MID TO UPPER 50S WHICH IS VERY SIMILAR TO THE PREVIOUS FORECAST. GRADUALLY MORE SUNSHINE THROUGH THE DAY MONDAY...ESPECIALLY WEST OF THE MISSISSIPPI RIVER...AND 850MB TEMPS AROUND 12C FAVOR TEMPERATURES CLIMBING INTO THE MID TO UPPER 70S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 250 PM CDT SUN JUN 9 2013 FOCUS REMAINS ON POSSIBLE SEVERE WEATHER AND FLOODING...PARTICULARLY TUESDAY NIGHT AND WEDNESDAY. THE UPPER RIDGING THAT HAS BEEN IN PLACE FOR AWHILE OVER THE DESERT SOUTHWEST REMAINS FORECAST TO SHIFT EAST AND BUILD INTO THE CENTRAL AND SOUTHERN PLAINS BY 12Z TUESDAY. PLENTY OF WARM AIR WILL EXIST UNDER THE RIDGE WITH 850MB STANDARDIZED TEMPERATURE ANOMALIES CLIMBING TO 1.5-2.5 ABOVE NORMAL OVER KANSAS...OKLAHOMA AND MISSOURI FOR TUESDAY AND WEDNESDAY. EXPECT WITH THIS BUILDING RIDGING AND WARMING TO HAVE A WARM FRONT AT THE SURFACE. HOW FAR NORTH THIS WARM FRONT GETS WILL HAVE A MAJOR IMPACT ON TEMPERATURES...PRECIPITATION CHANCES AND POTENTIAL FOR SEVERE WEATHER/FLOODING FOR THE FORECAST AREA. THE FEATURE HELPING TO PULL THE WARM FRONT NORTH APPEARS TO BE THE UPPER LOW OFF THE COAST OF SOUTHERN CALIFORNIA. AS THIS UPPER LOW COMES ACROSS UTAH AND WYOMING ON TUESDAY...INCREASING SOUTHERLY FLOW AHEAD OF IT SHOULD PROPEL THE FRONT NORTH TO AT LEAST I-70 BY 00Z WEDNESDAY PER MODEL CONSENSUS. THE 09.12Z NAM/CANADIAN LIFT IT ALMOST TO I-80 IN IOWA AT THE SAME TIME. WHERE IT ENDS UP AT 00Z WEDNESDAY IS CRITICAL BECAUSE THERE IS A VERY STRONG CONSENSUS FOR MCS ACTIVITY TO FIRE JUST NORTH OF THE FRONT IN THE EVENING...ON THE EDGE OF THE 700MB CAPPING...THEN TRACKING EAST-SOUTHEAST PER CORFIDI VECTORS. MODELS TRENDS FROM THE GFS...NAM AND ECMWF SUGGEST A FARTHER SOUTH POSITION WITH THE WARM FRONT...BUT IT IS STILL HARD TO SAY AT THIS TIME WHETHER IT GETS BOTTLED UP NEAR THE MISSOURI/IOWA BORDER OR GETS PERHAPS AS FAR NORTH AS US HWY 20. SINCE THE TREND HAS BEEN SOUTH...SHIFTED THE POPS ABOUT 30 MILES SOUTH FROM THE PREVIOUS FORECAST TO COME BETTER IN-LINE WITH THE CONSENSUS. THESE MAY NEED TO BE SHIFTED FARTHER SOUTH IN LATER FORECASTS. SEEMS LIKE THE BEST TIME PERIOD RIGHT NOW FOR AN MCS WITH SEVERE WEATHER POTENTIAL...INCLUDING LARGE HAIL...DAMAGING WINDS AND HEAVY RAIN TO AFFECT THE FORECAST AREA...MAINLY SOUTH OF I-90...WOULD OCCUR BETWEEN 06Z-15Z WEDNESDAY. OTHERWISE...THE ONLY OTHER HIGHLIGHTS FOR MONDAY NIGHT THROUGH WEDNESDAY ARE: 1. SOME POTENTIAL FOR VALLEY FOG ON MONDAY NIGHT WITH CLEARING EVENING SKIES AND MOIST SOILS. 2. TEMPERATURES A FEW DEGREES ABOVE NORMAL ON TUESDAY AS 850MB TEMPS CLIMB TO 14-17C NORTH TO SOUTH. 3. POTENTIAL FOR A DRIER WEDNESDAY AFTERNOON DUE TO SUBSIDENCE IN THE WAKE OF THE MCS AND LOW LEVEL MOISTURE TRANSPORT SHIFTING OFF TO THE EAST. THERE MAY NOT BE ANY INSTABILITY LEFT BY THE TIME THE UPPER LOW...LIKELY A SHEARED OUT SHORTWAVE NOW...BEGINS TO APPROACH THE FORECAST AREA LATE IN THE DAY. 09.12Z GFS/CANADIAN ARE DRY...BUT THE 09.12Z ECMWF MAINTAINS SOME ISO-SCT CONVECTION...THUS SOME PRECIPITATION CHANCES CONTINUE. FOR WEDNESDAY NIGHT INTO NEXT WEEKEND...STRONG MODEL CONSENSUS EXISTS FOR A FAIRLY DEEP TROUGH TO DEVELOP OVER THE PACIFIC NORTHWEST EARLY IN THE PERIOD...AMPLIFYING A RIDGE DOWNSTREAM OVER THE DAKOTAS INTO SOUTH CENTRAL CANADA. THIS SETS UP A NORTHWEST FLOW OVER THE FORECAST AREA...HELPING TO TAKE THAT SHEARED OUT SHORTWAVE AT THE TIME NEAR/OVER THE FORECAST AREA SOUTHEAST TOWARDS THE OHIO VALLEY. THIS LEADS TO A DRIER...BUT NOT COMPLETELY DRY...WEDNESDAY NIGHT FORECAST. A RIDGE OF CANADIAN HIGH PRESSURE SHOULD THEN BUILD IN FOR THURSDAY AND THURSDAY NIGHT...PROVIDING DRY AND SEASONABLE WEATHER WITH 850MB TEMPS AROUND NORMAL. ON FRIDAY...PART OF THE PACIFIC NORTHWEST TROUGH IS PROGGED TO EJECT NORTHEAST...WHILE THE REST OF IT APPEARS TO RETROGRADE WEST SLIGHTLY. THE PART THAT EJECTS NORTHEAST HELPS TO PUSH THE RIDGING OVER THE DAKOTAS INTO THE FORECAST AREA LATE FRIDAY OR FRIDAY NIGHT...YIELDING SOME WARMER TEMPERATURES. WE SHOULD ALSO SEE A COLD FRONT APPROACH/CROSS THE AREA FRIDAY NIGHT INTO SATURDAY ASSOCIATED WITH THE SHORTWAVE... REQUIRING CHANCES OF SHOWERS AND THUNDERSTORMS. MAY BE DEALING WITH MCS ACTIVITY DURING THIS PERIOD AS WELL...THOUGH PRESENT INDICATIONS ARE THAT THE MCSS WILL STAY TO THE SOUTH. BY SUNDAY...THERE ARE UNCERTAINTIES ON HOW FAR SOUTH/EAST THE COLD FRONT WILL BE. THE 09.12Z GFS/ECMWF HANG IT UP JUST TO OUR SOUTH AND WITH MOIST LOW LEVELS LINGERING...COULD BE DEALING WITH SCATTERED SHOWERS/STORMS OVER THE AREA. GIVEN THE UNCERTAINTIES...HAVE KEPT CONSENSUS 20-30 PERCENT CHANCES FOR SUNDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 640 PM CDT SUN JUN 9 2013 STACKED LOW ROTATING ACROSS THE REGION CONTINUES TO SLOWLY MOVE SOUTHEAST. BULK OF SHOWER ACTIVITY IS AHEAD AND NORTHEAST OF LOW WITH BETTER MOISTURE TRANSPORT...BUT SOME INSTABILITY ALSO CREATING SHOWERS AND ISOLATED THUNDERSTORMS CLOSER TO LOW ACROSS CENTRAL IOWA. WHILE VFR CONDITIONS STILL EXIST ALONG AND NEAR MINNESOTA/ IOWA BORDER...MVFR MORE LIKELY SCENARIO GOING THROUGH EVENING. AS LOW CONTINUES TO SHIFT SOUTHEAST...AND ANY MINOR INSTABILITY DISSIPATES BULK OF PRECIPITATION WILL ALSO SHIFT OUT OR END OVERNIGHT. LINGERING CLOUDS COULD LIMIT THE EXTENT OF LIFR CONDITIONS OR REAL LOW VISIBILITIES BUT WIDESPREAD IFR CONDITIONS EXPECTED ON NORTH AND NORTHEAST SIDE OF LOW. AS NORTHWEST FLOW DEVELOPS ON MONDAY...AND BEST LOW LEVEL MOISTURE BEGINS TO ADVECT EAST...STRATUS FIELD SHOULD BEGIN TO BREAK UP FROM WEST TO EAST FOR IMPROVED AVIATION CONDITIONS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM....AJ AVIATION.....SHEA
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
252 PM CDT SAT JUN 8 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 251 PM CDT SAT JUN 8 2013 CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S....A POTENT SHORTWAVE TROUGH DIGGING SOUTH INTO CENTRAL NEBRASKA...WEAK SHORTWAVE RIDGING BUILDING OVER THE FORECAST AREA AND A SHORTWAVE OVER NORTHEAST WI. THE NORTHEAST WI SHORTWAVE WAS RESPONSIBLE FOR THE SHOWERS AND ISOLATED THUNDERSTORMS THIS MORNING NORTHEAST OF I-94. MORE SHOWERS EXIST OVER WESTERN IOWA...SOUTHWEST MN AND BACK INTO SOUTH DAKOTA AND NEBRASKA...ALL ASSOCIATED WITH DPVA AND INCREASING 850MB MOISTURE TRANSPORT AHEAD OF THE DIGGING SHORTWAVE TROUGH. 12Z RAOB DATA FROM GGW AND UNR SHOWED 500MB HEIGHT FALLS OF 40-60 METERS WITH THE SHORTWAVE. MOISTURE AHEAD OF THIS SHORTWAVE RANGES FROM 1 TO 1.5 INCHES OF PRECIPITABLE WATER PER GOES DERIVED IMAGERY...HIGHEST OVER EASTERN NEBRASKA...WHICH IS 100-150 PERCENT OF NORMAL. ALTOSTRATUS HAS SPREAD EAST ACROSS MUCH OF THE FORECAST AREA DOWNSTREAM OF THIS SHORTWAVE TROUGH...AIDED TOO BY UPPER LEVEL DIVERGENCE IN A RIGHT ENTRANCE REGION OF A 70 KT JET ON THE SOUTH SIDE OF THAT NORTHEAST WI SHORTWAVE. MODELS CONTINUE THE TREND WITH THE POTENT SHORTWAVE OVER CENTRAL NEBRASKA TO SLOW IT DOWN AND DIG SOUTHEAST MORE. COMPARE AT 12Z SUNDAY WHERE THE 07.12Z NAM DEPICTED A FORMING UPPER LOW NEAR MONTEVIDEO MN...AND NOW THE 08.12Z NAM IS NEAR SIOUX CITY IA. THE 08.12Z REGIONAL CANADIAN IS EVEN FARTHER SOUTH...NEAR OMAHA. THIS HAS IMPLICATIONS ON HOW FAST PRECIPITATION SPREADS EAST. WITH THE GENERAL SLOW DOWN OF THE POTENT SHORTWAVE AND EVENTUALLY THE CLOSED OFF UPPER LOW THAT FORMS...HAVE DELAYED THE SPREAD EASTWARD OF THE SHOWERS. ADDITIONALLY...THE SLOW DOWN RESULTS IN INSTABILITY TAKING LONGER TO GET NORTH INTO THE AREA. THUS...HAVE PULLED MOST OF THE THUNDER CHANCES FOR TONIGHT EXCEPT IN NORTHEAST IA LATE IN THE NIGHT. INTERESTINGLY...THERE APPEARS TO BE 2 SEPARATE SHOWER BANDS FOR TONIGHT. THE FIRST IS A WARM ADVECTION BAND...SEEN ON THE 310 K SURFACE AND OBSERVED RIGHT NOW ON RADAR BETWEEN ROCHESTER AND CHARLES CITY. THIS BAND IS HIGHER BASED AND HAVING TO CONTEND WITH LOWER LEVEL DRY AIR...PRECLUDING ANY PRECIP FROM REACHING THE GROUND. RAP/HRRR RUNS HAVE BEEN VERY PERSISTENT OF THIS BAND SPREADING SOUTHEAST THROUGH THE FORECAST AREA THROUGH THE EVENING...THEN LIFTING NORTH OVERNIGHT. TRIED TO PLAY THIS BAND WITH THE PRECIPITATION CHANCES...WITH SOME DRYING INDICATED AFTER MIDNIGHT IN PORTIONS OF NORTHEAST IA AND SOUTHWEST WI. THE NEXT SHOWER BAND WOULD BE THE TRUE WARM CONVEYOR BELT DOWNSTREAM OF THE FORMING UPPER LOW. THIS REALLY STARTS TO GET INTO THE FORECAST AREA AFTER MIDNIGHT...ESPECIALLY WEST OF THE MS RIVER. FOR SUNDAY...THE WARM CONVEYOR BELT WILL SLIDE OVER MUCH OF THE AREA DURING THE MORNING...THEN GET STUCK AS THE UPPER LOW HEADS INTO CENTRAL IA. IT APPEARS THERE SHOULD BE SOME FORM OF THE BELT WEAKENING DURING THE LATE MORNING HOURS...AS THE FORCING FOCUS SHIFTS UP TOWARDS CENTRAL MN. HOWEVER...BEING IN AGEOSTROPHIC CURVATURE DIVERGENCE AT 500MB ...PLUS DAYTIME HEATING AND MINIMAL CAPPING SHOULD YIELD PERSISTENT SHOWERS. SOME THUNDERSTORMS STILL LOOK LIKE A GOOD BET ON SUNDAY AS THE HEATING BOOSTS MLCAPES UPWARDS OF 500 TO AT MOST 1000 J/KG. MUCH OF THIS CAPE IS TALL AND SKINNY...AND WITH 0-6KM SHEAR VALUES GENERALLY 25 KT OR LESS...NOT ANTICIPATING ANY ORGANZIED SEVERE STORMS. ANY POTENTIAL FOR NON-SUPERCELL TORNADOES...IF THEY WERE TO OCCUR...WOULD STAY WEST OF THE FORECAST AREA...CLOSER TO THE PROGGED SURFACE LOW. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 251 PM CDT SAT JUN 8 2013 FOR SUNDAY NIGHT THROUGH MONDAY...WILL BE WATCHING THE EASTWARD PROGRESSION OF THE CLOSED LOW WHILE A RIDE OF HIGH PRESSURE BUILDS EAST FROM THE CENTRAL PLAINS. GFS AND NAM WANT TO PUSH THE LOW EAST INTO INDIANA WHILE THE GEM/EC LINGER IT FARTHER WEST WITH OUR AREA ON THE WESTERN PERIPHERY. EITHER WAY...APPEARS PR THE BUFKIT DATA THAT THERE WILL BE PLENTY OF CUMULUS DEVELOPMENT GIVEN STEEP LOWER-LEVEL LAPSE RATE. THE GFS/ECMWF BOTH IN AGREEMENT IN DEVELOPING SHOWERS WHILE THE NAM/GEM ARE BOTH DRY GIVEN STRENGTHENING MID-LEVEL RIDGING/SUBSIDENCE CAP OVER THE CUMULUS. WILL TAKE MODEL CONSENSUS APPROACH AT THIS TIME WHICH INCLUDES A 20-40 PERCENT PROBABILITY FOR SHOWERS IN THE MORNING...TAPERING INTO THE 20-30 RANGE DURING THE AFTERNOON MAINLY EAST OF THE MISSISSIPPI RIVER DURING THE AFTERNOON AS THE RIDGE BUILDS IN MORE. BRIEF RESPITE FROM RAIN EXPECTED TO OCCUR MONDAY NIGHT INTO TUESDAY WITH FURTHER RIDGE-BUILDING TAKING PLACE INTO OUR AREA. THIS WILL BE BRIEF INDEED AS MODELS SHOWING A WAVE OF LOW PRESSURE MOVING NORTHEAST OUT OF THE COLORADO ROCKIES INTO THE CENTRAL PLAINS/IA TUESDAY NIGHT THROUGH WEDNESDAY. THIS PUSHES A WARM FRONT NORTHWARD INTO NORTHERN IA THROUGH NORTHERN IL WITH MODERATE 850MB MOISTURE TRANSPORT IMPINGING INTO SOUTHERN PORTIONS///SOUTH OF I-90//. THIS LOOKS LIKE A GOOD SET UP FOR SHOWER/THUNDERSTORMS ALONG AND NORTH OF THE WARM FRONT WITH SOME HEAVIER RAINFALL POSSIBLE AS PRECIPITABLE WATER VALUES NUDGE UPWARD INTO THE 1.5 TO 2.0 INCH RANGE. IF THIS COMES TO FRUITION...COULD BE LOOKING AT THE POTENTIAL FOR SOME HYDROLOGY PROBLEMS SOUTH OF I-90. LATEST ECMWF/GFS TAKE THE WAVE OF LOW PRESSURE SOUTHEAST OF THE AREA WEDNESDAY NIGHT FOR TAPERING SHOWER/THUNDERSTORM CHANCES. FOR THURSDAY THROUGH SATURDAY...THE MODELS ARE CONSISTENT IN BUILDING A MID/UPPER LEVEL RIDGE ACROSS THE MIDDLE CONUS WITH WARMING ACROSS OUR AREA. DOESNT APPEAR TO BE COMPLETELY RAIN-FREE AT THIS POINT AS A COUPLE WEAK WAVE MOVE THROUGH THE RIDGE FOR PERIODIC SMALLER-END SHOWER/THUNDERSTORM CHANCES. COULD SEE THIS PERIOD BECOMING DRY WITH SUBSEQUENT MODEL RUNS GIVEN STRENGTHENING MID-LEVEL CAP. WE WILL KEEP AN EYE ON THIS FOR A MUCH-NEEDED DRYING OUT PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1242 PM CDT SAT JUN 8 2013 A FEW DIFFERENT WAVES OF PRECIPITATION HEADING TOWARD KRST/KLSE IN THE NEXT 24 HOURS WITH THE BIG IDEA OF DETERIORATING FLYING CONDITIONS...ESPECIALLY AFTER MIDNIGHT TONIGHT. FIRST WARM AIR ADVECTION WING OF SHOWERS WILL LIKELY PUSH INTO SE MINNESOTA BY MID/LATE AFTERNOON. THIS MAY NOT REACH KLSE UNTIL AFTER 02Z. THEN AS THE MAIN LOW MOVES NEARBY...A STEADIER BAND OF RAIN WILL PIVOT THROUGH. THE HIGHEST...HEAVIER RAIN CHANCES COME AFTER MIDNIGHT...AND IFR CONDITIONS ARE LIKELY AT KRST BY SUNRISE SUNDAY AND LOW-END MVFR AT KLSE. HAVE REMOVED THUNDER CHANCES IN THE MORNING SINCE INSTABILITY WEDGE IS KEPT WELL SOUTH. WARM FRONT LIFTS THROUGH LATE SUNDAY MORNING...BRINGING IMPROVING CEILINGS. GUSTY SOUTHERLY WINDS AND SCATTERED SHOWERS/STORMS WILL DEVELOP IN THE WAKE OF THE FRONTAL PASSAGE AND THIS MAY WARRANT A THUNDER MENTION BEGINNING BY 18Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...DAS AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1242 PM CDT SAT JUN 8 2013 .UPDATE... ISSUED AT 651 AM CDT SAT JUN 8 2013 CONTINUE TO UPDATE THE FORECAST FOR THE AREA ALONG AND NORTH OF I-94 WITH THE STRONG SHORTWAVE TROUGH MOVING THROUGH NORTHERN WI...THE SHOWERS CONTINUE TO FORM. ISOLATED TSRA ARE ALSO OCCURRING WITH CLOUD-GROUND LIGHTNING STRIKES IN THE MEDFORD- WAUSAU AREA. LOOKING AT THE Q-VECTOR CONVERGENCE FROM 500-300MB IT IS ASTOUNDINGLY STRONG FOR JUNE WITH A VERY NICE DIPOLE OF LIFT...FOLLOWED BY SUBSIDENCE POST-WAVE. THUS...HAVE REALLY INCREASED THE MORNING RAIN CHANCES AND ALSO ADDED THUNDER TO THE FORECAST. WOULD THINK MOS OF THE ACTIVITY ACROSS THE NORTH WOULD BE MOST ENHANCED THIS MORNING WITH A STABILITY BUILDING IN DURING THE AFTERNOON IN THE SUBSIDENT PART OF THE IMPULSE. HIGHS WILL LIKELY SUFFER A BIT TODAY AS WELL...BUT THIS IS TRICKY AND DIFFICULT TO DISCERN AT THIS TIME. NO CHANGES THERE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CDT SAT JUN 8 2013 THE MAIN FOCUS FOR TODAY AND TONIGHT IS WITH WHEN THE NEXT ROUND OF RAIN WILL MOVE INTO THE REGION FROM THE WEST AND WHEN ANY THUNDER MAY OCCUR. CURRENTLY...A PAIR OF MID LEVEL TROUGHS WERE NOTED VIA WATER VAPOR IMAGERY AND 08.07Z RAP ANALYSIS WITH ONE WEST TO EAST TROUGH FROM THE UP OF MICHIGAN INTO NORTHERN MINNESOTA AND ANOTHER...MORE VIGOROUS...WAVE DROPPING DOWN THROUGH EASTERN MONTANA. AT THE SURFACE...BROAD RIDGING CONTINUES TO DRIFT EAST ACROSS THE GREAT LAKES WITH A LOW ANALYZED IN EASTERN MONTANA. A FEW LIGHT RAIN SHOWERS HAVE DEVELOPED ACROSS WESTERN WISCONSIN ALONG WHAT APPEARS TO BE AN AREA OF CONVERGENCE BETWEEN 700-500MB. THESE SHOWERS WILL PERSIST THROUGH MUCH OF THE MORNING/EARLY AFTERNOON HOURS BEFORE THE CONVERGENCE SHIFTS TO THE NORTHEAST AND WEAKENS. MOST OF THE DAYTIME HOURS SHOULD BE DRY TODAY BEFORE THE NEXT SYSTEM MOVES IN FROM THE WEST THIS EVENING. NOT MUCH IN THE WAY OF 850MB WARM AIR ADVECTION KICKING IN UNTIL THIS EVENING AHEAD OF THE WAVE...SO EXPECT THAT TEMPERATURES WILL ONLY BE ABLE TO MAX OUT IN THE LOW 70S BEFORE CLOUD COVER BECOMES MORE WIDESPREAD AND THICKENS THIS AFTERNOON. THE FOCUS THEN GOES TO WHEN THE RAIN WILL MOVE IN AS THE MAIN WING OF 850MB WARM AIR ADVECTION LIFTS INTO THE REGION. THE TREND WITH THE 08.00Z GUIDANCE HAS BEEN TO GO A BIT SLOWER AND SOUTHWEST WITH THE TROUGH/SURFACE LOW...SO HAVE SLIGHTLY SLOWED DOWN THE EASTWARD PROGRESSION OF THE RAIN GETTING IN LATE THIS AFTERNOON INTO THIS EVENING. AS IS CURRENTLY THE CASE IN SOUTH DAKOTA...EXPECT THAT THE BEST INITIAL THUNDER CHANCES WILL COME IN OVERNIGHT AS THE STRONGEST CHANNEL OF 850-925MB MOISTURE TRANSPORT NOSES UP INTO THE REGION. BASED ON 08.00Z GUIDANCE...HAVE INTRODUCED SOME THUNDER WEST OF THE RIVER BEFORE MIDNIGHT AND EAST OF THE RIVER AFTER MIDNIGHT WHICH FOLLOWS WHERE THIS MAIN LOW LEVEL TRANSPORT IS. AM NOT EXPECTING ANY SEVERE WEATHER WITH THIS ROUND AS INSTABILITY LOOKS TO BE FAIRLY WEAK AT JUST A FEW HUNDRED J/KG. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 349 AM CDT SAT JUN 8 2013 GOING INTO THE SUNDAY THE QUESTION IS WHAT WILL TRANSPIRE WITH THE MID LEVEL TROUGH AND SURFACE LOW. THE 08.00Z GFS/ECMWF/GEM ARE ALL IN GOOD AGREEMENT WITH THE TIMING...TRACK AND WEAKENING OF THE MID LEVEL TROUGH ON SUNDAY WITH A GENERAL TRACK OF IT GOING THROUGH CENTRAL IOWA DURING THE DAY. AS THE MID LEVEL LOW GETS CUT OFF...THE SURFACE LOW OCCLUDES AND APPEARS TO TRACK ACROSS NORTHERN IOWA THROUGH THE DAY AND EVENING HOURS. OF THESE THREE MODELS...THE GFS PRODUCES THE MOST 0-3KM MUCAPE IN THE AFTERNOON HOURS AT AROUND 1000 J/KG. HOWEVER...IT ALSO HAS SURFACE DEW POINTS IN THE MID 60S WHICH...WHEN MODIFIED TO AROUND 60 IN NORTHEAST IOWA AND SOUTHWEST WISCONSIN...ONLY PRODUCES A FEW HUNDRED J/KG OF 0-3KM MUCAPE. WIND SHEAR IS ALSO RELEGATED TO THE LOWEST 1 OR 2KM...SO THERE IS NOT MUCH DEEP SHEAR TO WORK WITH. THE 08.00Z NAM IS CONSIDERED TO BE AN OUTLIER AS IT IS MUCH DEEPER WITH THE CLOSING OFF OF THE LOW AND POSES SOME CHANCES FOR SEVERE WEATHER. WPC MENTIONS IN THE PMDHMD THIS MORNING THAT WHILE THE 00Z NAM HAS TRENDED TOWARD THE PREFERENCE OF THE OTHER MODELS...IT HAS ISSUES IN HOW IT IS HANDLING THE UPPER TROUGHING OVER CENTRAL CANADA. DESPITE THIS...THE PAST FEW RUNS OF THE NAM HAVE ALL SHOWN A SIMILAR SCENARIO WHERE CONVECTION DEVELOPS IN THE DRY SLOT ALONG WHAT APPEARS TO BE A SURFACE DRY LINE. THE 08.00Z NAM ALSO DEVELOPS TOO HIGH OF SURFACE DEW POINTS...MID TO UPPER 60S...WHICH YIELDS TOO HIGH OF INSTABILITY. HOWEVER...EVEN MODIFIED SOUNDINGS FOR A 60F SURFACE DEW POINT STILL BRINGS ABOUT 1000-1500 J/KG OF MUCAPE. WIND SHEAR IS ALL IN THE LOWEST 2-3KM...BUT DOES HAVE A LOT OF DIRECTIONAL SHEAR WITH IT. DESPITE THIS SCENARIO NOT LOOKING VERY LIKELY TO OCCUR...IT WILL HAVE TO BE MONITORED LEADING INTO SUNDAY DUE TO THE POTENTIAL OF MULTICELL CLUSTERS WITH STRONG WINDS WITH THESE STORMS...PARTICULARLY FOR WESTERN WISCONSIN. RAIN SHOWERS WILL GRADUALLY COME TO AN END ON MONDAY NIGHT AS THE TROUGH TRACKS TO THE EAST AND A BRIEF RIDGE OF HIGH PRESSURE MOVES IN FROM THE WEST. GOING INTO THE MIDDLE OF NEXT WEEK...IT LOOKS LIKE A WARM FRONT WILL STALL OUT ACROSS SOUTHERN MINNESOTA AND SOUTHERN WISCONSIN AND COULD LEAD TO SOME HEAVY RAIN FALLING ACROSS THIS REGION. PRETTY GOOD CONSISTENCY BETWEEN THE 08.00Z GFS/ECMWF WITH STARTING THIS RAIN UP ON TUESDAY NIGHT AND ENDING IT BY THURSDAY MORNING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1242 PM CDT SAT JUN 8 2013 A FEW DIFFERENT WAVES OF PRECIPITATION HEADING TOWARD KRST/KLSE IN THE NEXT 24 HOURS WITH THE BIG IDEA OF DETERIORATING FLYING CONDITIONS...ESPECIALLY AFTER MIDNIGHT TONIGHT. FIRST WARM AIR ADVECTION WING OF SHOWERS WILL LIKELY PUSH INTO SE MINNESOTA BY MID/LATE AFTERNOON. THIS MAY NOT REACH KLSE UNTIL AFTER 02Z. THEN AS THE MAIN LOW MOVES NEARBY...A STEADIER BAND OF RAIN WILL PIVOT THROUGH. THE HIGHEST...HEAVIER RAIN CHANCES COME AFTER MIDNIGHT...AND IFR CONDITIONS ARE LIKELY AT KRST BY SUNRISE SUNDAY AND LOW-END MVFR AT KLSE. HAVE REMOVED THUNDER CHANCES IN THE MORNING SINCE INSTABILITY WEDGE IS KEPT WELL SOUTH. WARM FRONT LIFTS THROUGH LATE SUNDAY MORNING...BRINGING IMPROVING CEILINGS. GUSTY SOUTHERLY WINDS AND SCATTERED SHOWERS/STORMS WILL DEVELOP IN THE WAKE OF THE FRONTAL PASSAGE AND THIS MAY WARRANT A THUNDER MENTION BEGINNING BY 18Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...BAUMGARDT SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
653 AM CDT SAT JUN 8 2013 .UPDATE... ISSUED AT 651 AM CDT SAT JUN 8 2013 CONTINUE TO UPDATE THE FORECAST FOR THE AREA ALONG AND NORTH OF I-94 WITH THE STRONG SHORTWAVE TROUGH MOVING THROUGH NORTHERN WI...THE SHOWERS CONTINUE TO FORM. ISOLATED TSRA ARE ALSO OCCURRING WITH CLOUD-GROUND LIGHTNING STRIKES IN THE MEDFORD- WAUSAU AREA. LOOKING AT THE Q-VECTOR CONVERGENCE FROM 500-300MB IT IS ASTOUNDINGLY STRONG FOR JUNE WITH A VERY NICE DIPOLE OF LIFT...FOLLOWED BY SUBSIDENCE POST-WAVE. THUS...HAVE REALLY INCREASED THE MORNING RAIN CHANCES AND ALSO ADDED THUNDER TO THE FORECAST. WOULD THINK MOS OF THE ACTIVITY ACROSS THE NORTH WOULD BE MOST ENHANCED THIS MORNING WITH A STABILITY BUILDING IN DURING THE AFTERNOON IN THE SUBSIDENT PART OF THE IMPULSE. HIGHS WILL LIKELY SUFFER A BIT TODAY AS WELL...BUT THIS IS TRICKY AND DIFFICULT TO DISCERN AT THIS TIME. NO CHANGES THERE. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CDT SAT JUN 8 2013 THE MAIN FOCUS FOR TODAY AND TONIGHT IS WITH WHEN THE NEXT ROUND OF RAIN WILL MOVE INTO THE REGION FROM THE WEST AND WHEN ANY THUNDER MAY OCCUR. CURRENTLY...A PAIR OF MID LEVEL TROUGHS WERE NOTED VIA WATER VAPOR IMAGERY AND 08.07Z RAP ANALYSIS WITH ONE WEST TO EAST TROUGH FROM THE UP OF MICHIGAN INTO NORTHERN MINNESOTA AND ANOTHER...MORE VIGOROUS...WAVE DROPPING DOWN THROUGH EASTERN MONTANA. AT THE SURFACE...BROAD RIDGING CONTINUES TO DRIFT EAST ACROSS THE GREAT LAKES WITH A LOW ANALYZED IN EASTERN MONTANA. A FEW LIGHT RAIN SHOWERS HAVE DEVELOPED ACROSS WESTERN WISCONSIN ALONG WHAT APPEARS TO BE AN AREA OF CONVERGENCE BETWEEN 700-500MB. THESE SHOWERS WILL PERSIST THROUGH MUCH OF THE MORNING/EARLY AFTERNOON HOURS BEFORE THE CONVERGENCE SHIFTS TO THE NORTHEAST AND WEAKENS. MOST OF THE DAYTIME HOURS SHOULD BE DRY TODAY BEFORE THE NEXT SYSTEM MOVES IN FROM THE WEST THIS EVENING. NOT MUCH IN THE WAY OF 850MB WARM AIR ADVECTION KICKING IN UNTIL THIS EVENING AHEAD OF THE WAVE...SO EXPECT THAT TEMPERATURES WILL ONLY BE ABLE TO MAX OUT IN THE LOW 70S BEFORE CLOUD COVER BECOMES MORE WIDESPREAD AND THICKENS THIS AFTERNOON. THE FOCUS THEN GOES TO WHEN THE RAIN WILL MOVE IN AS THE MAIN WING OF 850MB WARM AIR ADVECTION LIFTS INTO THE REGION. THE TREND WITH THE 08.00Z GUIDANCE HAS BEEN TO GO A BIT SLOWER AND SOUTHWEST WITH THE TROUGH/SURFACE LOW...SO HAVE SLIGHTLY SLOWED DOWN THE EASTWARD PROGRESSION OF THE RAIN GETTING IN LATE THIS AFTERNOON INTO THIS EVENING. AS IS CURRENTLY THE CASE IN SOUTH DAKOTA...EXPECT THAT THE BEST INITIAL THUNDER CHANCES WILL COME IN OVERNIGHT AS THE STRONGEST CHANNEL OF 850-925MB MOISTURE TRANSPORT NOSES UP INTO THE REGION. BASED ON 08.00Z GUIDANCE...HAVE INTRODUCED SOME THUNDER WEST OF THE RIVER BEFORE MIDNIGHT AND EAST OF THE RIVER AFTER MIDNIGHT WHICH FOLLOWS WHERE THIS MAIN LOW LEVEL TRANSPORT IS. AM NOT EXPECTING ANY SEVERE WEATHER WITH THIS ROUND AS INSTABILITY LOOKS TO BE FAIRLY WEAK AT JUST A FEW HUNDRED J/KG. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 349 AM CDT SAT JUN 8 2013 GOING INTO THE SUNDAY THE QUESTION IS WHAT WILL TRANSPIRE WITH THE MID LEVEL TROUGH AND SURFACE LOW. THE 08.00Z GFS/ECMWF/GEM ARE ALL IN GOOD AGREEMENT WITH THE TIMING...TRACK AND WEAKENING OF THE MID LEVEL TROUGH ON SUNDAY WITH A GENERAL TRACK OF IT GOING THROUGH CENTRAL IOWA DURING THE DAY. AS THE MID LEVEL LOW GETS CUT OFF...THE SURFACE LOW OCCLUDES AND APPEARS TO TRACK ACROSS NORTHERN IOWA THROUGH THE DAY AND EVENING HOURS. OF THESE THREE MODELS...THE GFS PRODUCES THE MOST 0-3KM MUCAPE IN THE AFTERNOON HOURS AT AROUND 1000 J/KG. HOWEVER...IT ALSO HAS SURFACE DEW POINTS IN THE MID 60S WHICH...WHEN MODIFIED TO AROUND 60 IN NORTHEAST IOWA AND SOUTHWEST WISCONSIN...ONLY PRODUCES A FEW HUNDRED J/KG OF 0-3KM MUCAPE. WIND SHEAR IS ALSO RELEGATED TO THE LOWEST 1 OR 2KM...SO THERE IS NOT MUCH DEEP SHEAR TO WORK WITH. THE 08.00Z NAM IS CONSIDERED TO BE AN OUTLIER AS IT IS MUCH DEEPER WITH THE CLOSING OFF OF THE LOW AND POSES SOME CHANCES FOR SEVERE WEATHER. WPC MENTIONS IN THE PMDHMD THIS MORNING THAT WHILE THE 00Z NAM HAS TRENDED TOWARD THE PREFERENCE OF THE OTHER MODELS...IT HAS ISSUES IN HOW IT IS HANDLING THE UPPER TROUGHING OVER CENTRAL CANADA. DESPITE THIS...THE PAST FEW RUNS OF THE NAM HAVE ALL SHOWN A SIMILAR SCENARIO WHERE CONVECTION DEVELOPS IN THE DRY SLOT ALONG WHAT APPEARS TO BE A SURFACE DRY LINE. THE 08.00Z NAM ALSO DEVELOPS TOO HIGH OF SURFACE DEW POINTS...MID TO UPPER 60S...WHICH YIELDS TOO HIGH OF INSTABILITY. HOWEVER...EVEN MODIFIED SOUNDINGS FOR A 60F SURFACE DEW POINT STILL BRINGS ABOUT 1000-1500 J/KG OF MUCAPE. WIND SHEAR IS ALL IN THE LOWEST 2-3KM...BUT DOES HAVE A LOT OF DIRECTIONAL SHEAR WITH IT. DESPITE THIS SCENARIO NOT LOOKING VERY LIKELY TO OCCUR...IT WILL HAVE TO BE MONITORED LEADING INTO SUNDAY DUE TO THE POTENTIAL OF MULTICELL CLUSTERS WITH STRONG WINDS WITH THESE STORMS...PARTICULARLY FOR WESTERN WISCONSIN. RAIN SHOWERS WILL GRADUALLY COME TO AN END ON MONDAY NIGHT AS THE TROUGH TRACKS TO THE EAST AND A BRIEF RIDGE OF HIGH PRESSURE MOVES IN FROM THE WEST. GOING INTO THE MIDDLE OF NEXT WEEK...IT LOOKS LIKE A WARM FRONT WILL STALL OUT ACROSS SOUTHERN MINNESOTA AND SOUTHERN WISCONSIN AND COULD LEAD TO SOME HEAVY RAIN FALLING ACROSS THIS REGION. PRETTY GOOD CONSISTENCY BETWEEN THE 08.00Z GFS/ECMWF WITH STARTING THIS RAIN UP ON TUESDAY NIGHT AND ENDING IT BY THURSDAY MORNING. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 653 AM CDT SAT JUN 8 2013 VFR CONDITIONS TODAY MAKE FOR NICE FLYING WEATHER. A STRONG SYSTEM WILL BE HEADING INTO THE TAF SITES TONIGHT WITH DETERIORATING CONDITIONS. WOULD THINK IFR IS MOST LIKELY 12Z SUNDAY AT KRST IN -SHRA...WITH LOW MVFR AT KLSE...AND POSSIBLY IFR TOO. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...BAUMGARDT SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
349 AM CDT SAT JUN 8 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CDT SAT JUN 8 2013 THE MAIN FOCUS FOR TODAY AND TONIGHT IS WITH WHEN THE NEXT ROUND OF RAIN WILL MOVE INTO THE REGION FROM THE WEST AND WHEN ANY THUNDER MAY OCCUR. CURRENTLY...A PAIR OF MID LEVEL TROUGHS WERE NOTED VIA WATER VAPOR IMAGERY AND 08.07Z RAP ANALYSIS WITH ONE WEST TO EAST TROUGH FROM THE UP OF MICHIGAN INTO NORTHERN MINNESOTA AND ANOTHER...MORE VIGOROUS...WAVE DROPPING DOWN THROUGH EASTERN MONTANA. AT THE SURFACE...BROAD RIDGING CONTINUES TO DRIFT EAST ACROSS THE GREAT LAKES WITH A LOW ANALYZED IN EASTERN MONTANA. A FEW LIGHT RAIN SHOWERS HAVE DEVELOPED ACROSS WESTERN WISCONSIN ALONG WHAT APPEARS TO BE AN AREA OF CONVERGENCE BETWEEN 700-500MB. THESE SHOWERS WILL PERSIST THROUGH MUCH OF THE MORNING/EARLY AFTERNOON HOURS BEFORE THE CONVERGENCE SHIFTS TO THE NORTHEAST AND WEAKENS. MOST OF THE DAYTIME HOURS SHOULD BE DRY TODAY BEFORE THE NEXT SYSTEM MOVES IN FROM THE WEST THIS EVENING. NOT MUCH IN THE WAY OF 850MB WARM AIR ADVECTION KICKING IN UNTIL THIS EVENING AHEAD OF THE WAVE...SO EXPECT THAT TEMPERATURES WILL ONLY BE ABLE TO MAX OUT IN THE LOW 70S BEFORE CLOUD COVER BECOMES MORE WIDESPREAD AND THICKENS THIS AFTERNOON. THE FOCUS THEN GOES TO WHEN THE RAIN WILL MOVE IN AS THE MAIN WING OF 850MB WARM AIR ADVECTION LIFTS INTO THE REGION. THE TREND WITH THE 08.00Z GUIDANCE HAS BEEN TO GO A BIT SLOWER AND SOUTHWEST WITH THE TROUGH/SURFACE LOW...SO HAVE SLIGHTLY SLOWED DOWN THE EASTWARD PROGRESSION OF THE RAIN GETTING IN LATE THIS AFTERNOON INTO THIS EVENING. AS IS CURRENTLY THE CASE IN SOUTH DAKOTA...EXPECT THAT THE BEST INITIAL THUNDER CHANCES WILL COME IN OVERNIGHT AS THE STRONGEST CHANNEL OF 850-925MB MOISTURE TRANSPORT NOSES UP INTO THE REGION. BASED ON 08.00Z GUIDANCE...HAVE INTRODUCED SOME THUNDER WEST OF THE RIVER BEFORE MIDNIGHT AND EAST OF THE RIVER AFTER MIDNIGHT WHICH FOLLOWS WHERE THIS MAIN LOW LEVEL TRANSPORT IS. AM NOT EXPECTING ANY SEVERE WEATHER WITH THIS ROUND AS INSTABILITY LOOKS TO BE FAIRLY WEAK AT JUST A FEW HUNDRED J/KG. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 349 AM CDT SAT JUN 8 2013 GOING INTO THE SUNDAY THE QUESTION IS WHAT WILL TRANSPIRE WITH THE MID LEVEL TROUGH AND SURFACE LOW. THE 08.00Z GFS/ECMWF/GEM ARE ALL IN GOOD AGREEMENT WITH THE TIMING...TRACK AND WEAKENING OF THE MID LEVEL TROUGH ON SUNDAY WITH A GENERAL TRACK OF IT GOING THROUGH CENTRAL IOWA DURING THE DAY. AS THE MID LEVEL LOW GETS CUT OFF...THE SURFACE LOW OCCLUDES AND APPEARS TO TRACK ACROSS NORTHERN IOWA THROUGH THE DAY AND EVENING HOURS. OF THESE THREE MODELS...THE GFS PRODUCES THE MOST 0-3KM MUCAPE IN THE AFTERNOON HOURS AT AROUND 1000 J/KG. HOWEVER...IT ALSO HAS SURFACE DEW POINTS IN THE MID 60S WHICH...WHEN MODIFIED TO AROUND 60 IN NORTHEAST IOWA AND SOUTHWEST WISCONSIN...ONLY PRODUCES A FEW HUNDRED J/KG OF 0-3KM MUCAPE. WIND SHEAR IS ALSO RELEGATED TO THE LOWEST 1 OR 2KM...SO THERE IS NOT MUCH DEEP SHEAR TO WORK WITH. THE 08.00Z NAM IS CONSIDERED TO BE AN OUTLIER AS IT IS MUCH DEEPER WITH THE CLOSING OFF OF THE LOW AND POSES SOME CHANCES FOR SEVERE WEATHER. WPC MENTIONS IN THE PMDHMD THIS MORNING THAT WHILE THE 00Z NAM HAS TRENDED TOWARD THE PREFERENCE OF THE OTHER MODELS...IT HAS ISSUES IN HOW IT IS HANDLING THE UPPER TROUGHING OVER CENTRAL CANADA. DESPITE THIS...THE PAST FEW RUNS OF THE NAM HAVE ALL SHOWN A SIMILAR SCENARIO WHERE CONVECTION DEVELOPS IN THE DRY SLOT ALONG WHAT APPEARS TO BE A SURFACE DRY LINE. THE 08.00Z NAM ALSO DEVELOPS TOO HIGH OF SURFACE DEW POINTS...MID TO UPPER 60S...WHICH YIELDS TOO HIGH OF INSTABILITY. HOWEVER...EVEN MODIFIED SOUNDINGS FOR A 60F SURFACE DEW POINT STILL BRINGS ABOUT 1000-1500 J/KG OF MUCAPE. WIND SHEAR IS ALL IN THE LOWEST 2-3KM...BUT DOES HAVE A LOT OF DIRECTIONAL SHEAR WITH IT. DESPITE THIS SCENARIO NOT LOOKING VERY LIKELY TO OCCUR...IT WILL HAVE TO BE MONITORED LEADING INTO SUNDAY DUE TO THE POTENTIAL OF MULTICELL CLUSTERS WITH STRONG WINDS WITH THESE STORMS...PARTICULARLY FOR WESTERN WISCONSIN. RAIN SHOWERS WILL GRADUALLY COME TO AN END ON MONDAY NIGHT AS THE TROUGH TRACKS TO THE EAST AND A BRIEF RIDGE OF HIGH PRESSURE MOVES IN FROM THE WEST. GOING INTO THE MIDDLE OF NEXT WEEK...IT LOOKS LIKE A WARM FRONT WILL STALL OUT ACROSS SOUTHERN MINNESOTA AND SOUTHERN WISCONSIN AND COULD LEAD TO SOME HEAVY RAIN FALLING ACROSS THIS REGION. PRETTY GOOD CONSISTENCY BETWEEN THE 08.00Z GFS/ECMWF WITH STARTING THIS RAIN UP ON TUESDAY NIGHT AND ENDING IT BY THURSDAY MORNING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1103 PM CDT FRI JUN 7 2013 ALTOSTRATUS AND CIRROSTRATUS CLOUDS HAVE BEEN STREAMING ACROSS THE TAF SITES FROM THE DAKOTAS...AHEAD OF A STORM SYSTEM DEVELOPING THERE. THESE CLOUDS LOOK TO PERSIST THROUGH MUCH OF THE MORNING HOURS...WHICH SHOULD HELP PRECLUDE RADIATIONAL FOG FORMATION. DRIER AIR BELOW THESE CLOUDS...ASSOCIATED WITH HIGH PRESSURE IN PLACE...WILL ALSO KEEP CONDITIONS VFR. PLAN ON THE HIGH TO SLOWLY DRIFT OFF TO THE EAST DURING THE DAY...RESULTING IN INCREASING SOUTHEAST WINDS. THESE WINDS LOOK TO INCREASE FURTHER INTO THE EVENING AS THE STORM SYSTEM PROGRESSES TO THE EAST. SOME CONCERN OF LOW LEVEL WIND SHEAR AT RST...BUT IT APPEARS THE WINDS AT THE SURFACE SHOULD BE STRONG ENOUGH TO PRECLUDE THE NEED...AT LEAST BEFORE 06Z. IN ADDITION TO THE INCREASING WINDS...EXPECTING SHOWERS TO BEGIN MOVING TOWARDS THE TAF SITES DURING THE EVENING HOURS. WITH DRIER AIR IN PLACE UP TO AT LEAST 3000-4000 FT ABOVE THE GROUND...HAVE KEPT BOTH VISIBILITIES AND CEILINGS VFR. BETTER SHOT FOR LOWERING VISIBILITIES AND CEILINGS WILL OCCUR AFTER 06Z...ESPECIALLY AT KRST. COULD SEE SOME THUNDERSTORMS AS WELL AFTER 06Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...AJ
AREA FORECAST DISCUSSION...CORRECTED AVIATION
NWS CHEYENNE WY
1147 AM MDT SAT JUN 8 2013 .UPDATE... ISSUED AT 1134 AM MDT SAT JUN 8 2013 UPPER LEVEL SHORTWAVE HAS MOVED INTO WESTERN NEBRASKA LATE THIS MORNING...WITH SHOWERS EXITING EAST OF OUR PANHANDLE ZONES. WATER VAPOR IMAGERY SHOWS A WEAK DISTURBANCE MOVING SOUTHEAST THROUGH CENTRAL WYOMING. THIS FEATURE WILL CONTINUE TO MOVE ACROSS SOUTHEAST WYOMING THIS AFTERNOON. THE 15Z HRRR INDICATES ISOLATED CONVECTION DEVELOPING ALONG AND EAST OF THE LARAMIE RANGE THIS AFTERNOON. CAPE VALUES DO NOT EXCEED 200 J/KG...SO TSTORMS WILL BE WEAK AND PRODUCE SOME GUSTY WINDS BUT LITTLE RAINFALL. THE PRESSURE GRADIENT WILL REMAIN TIGHT ALONG AND EAST OF THE LARAMIE RANGE THIS AFTERNOON WITH NORTH TO NORTHWEST WINDS GUSTING AS HIGH AS 40 MPH. && .SHORT TERM...(TODAY THROUGH SUNDAY NIGHT) ISSUED AT 213 AM MDT SAT JUN 8 2013 SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE INTO THE MID MORNING OVER THE NORTH AND EAST PARTS OF THE CWA. THE ACTIVITY WAS AHEAD OF A SHORTWAVE TROUGH MOVING INTO EASTERN MONTANA AND WYOMING EARLY THIS MORNING. THE SHORTWAVE TROUGH WILL BE EAST OF THE CWA BY AROUND 18Z. THE PRECIPITATION WILL TAPER OFF THIS MORNING AND END IN THE EARLY EVENING, THE ASSOCIATED SURFACE COLD FRONT WAS OVER THE FAR NORTH PART OF THE CWA EARLY THIS MORNING AND SHOULD BE EAST AND SOUTH OF THE ENTIRE CWA BY 18Z. UPSTREAM THREE HOURLY SURFACE PRESSURE RISES WERE UP TO 2MB BEHIND THE FRONT AS OF 08Z. HIGH TEMPERATURES FOR TODAY WILL BE SIMILAR TO THOSE OF FRIDAY. THE DAY WILL START OFF MILD...WITH COLD AIR ADVECTION SLOWING WARMING DURING THE DAY. BEHIND THE FRONT WILL BE NORTHWEST TO NORTH WINDS GUSTING AS HIGH AS 40 MPH TODAY. THE REST OF THE FORECAST THROUGH 12Z MONDAY WILL BE DRY ACROSS THE CWA WITH LIGHTER WINDS AND MOSTLY CLEAR SKIES. A RIDGE OF HIGH PRESSURE IN THE UPPER ATMOSPHERE WILL BE OVER THE ROCKIES SUNDAY NIGHT. HIGHS FOR SUNDAY WILL BE 5 TO 10 DEGREES WARMER THAN THOSE OF TODAY AS HEIGHTS AND 700 MB TEMPERATURES RISE. SUNDAY NIGHT WILL BE ANOTHER MILD NIGHT. .LONG TERM...(MONDAY THROUGH FRIDAY) ISSUED AT 213 AM MDT SAT JUN 8 2013 MONDAY...QUITE HOT WITH RIDGING AND WESTERLY FLOW ALOFT ALONG WITH 700 MB TEMPERATURES NEAR 18 CELSIUS...YIELDING MAXIMUM TEMPERATURES WELL INTO THE 90S EAST OF INTERSTATE 25. PLEASE SEE CLIMATE SECTION. WARM TEMPERATURES ALOFT WILL ACT TO PROVIDE ENOUGH CONVECTIVE INHIBITION...CIN...AND WITH LIMITED LOW AND MID LEVEL MOISTURE...ONLY ISOLATED LATE DAY THUNDERSTORMS ON TAP OVER THE NORTHERN LARAMIE RANGE. TUESDAY...WEAK POSITIVELY TILTED SHORTWAVE TROUGH ALOFT MOVES OVERHEAD BUT WITH LIMITED LOW AND MID LEVEL MOISTURE...ONLY ISOLATED LATE DAY THUNDERSTORMS EXPECTED FROM DOUGLAS TO LUSK...DRY ELSEWHERE. ANOTHER HOT DAY WITH PROJECTED 700 MB TEMPERATURES FROM 16 TO 18 CELSIUS. WEDNESDAY...EVEN THOUGH HEIGHTS ALOFT INCREASE...MAXIMUM TEMPERATURES WILL BE COOLER DUE TO INCREASING UPSLOPE WINDS. DRY DAY WITH LACK OF LOW AND MID LEVEL MOISTURE AND SUBSIDENCE ALOFT. THURSDAY...SOUTHWEST FLOW ALOFT INCREASES AHEAD OF THE SHORTWAVE TROUGH APPROACHING FROM THE PACIFIC NORTHWEST STATES. SLIGHTLY WARMER THAN WEDNESDAY WITH PROJECTED THICKNESSES AND 700 MB TEMPERATURES EXCEEDING 18 CELSIUS. FRIDAY...COLD FRONTAL PASSAGE WILL TAKE SOME OF THE EDGE OFF...WITH RESPECT TO THE HEAT. ENOUGH LOW AND MID LEVEL MOISTURE FOR ISOLATED LATE DAY THUNDERSTORMS FROM DOUGLAS TO LUSK NEAR A LOW LEVEL CONVERGENCE BOUNDARY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY MORNING) ISSUED AT 1134 AM MDT SAT JUN 8 2013 VFR CONDITIONS WILL PREVAIL THROUGH SUNDAY MORNING. A WEAK WEATHER DISTURBANCE IN THE UPPER LEVELS WILL MOVE SOUTHEAST THROUGH THE AREA THIS AFTERNOON. ISOLATED SHOWERS AND A FEW TSTORMS WILL DEVELOP ALONG AND EAST OF THE LARAMIE RANGE. BEST CHANCES FOR TSTORMS APPEARS TO BE ACROSS PORTIONS OF THE NORTHERN NEBRASKA PANHANDLE. HAVE INCLUDED VCTS WITH SCT050CB AT CHADRON. ELSEWHERE...TSTORM COVERAGE WILL BE TOO ISOLATED TO MENTION IN TAFS. SCATTERED TO BROKEN CUMULUS WILL DISSIPATE AFTER SUNSET WITH CLEAR SKIES FOR THE REMAINDER OF THE FORECAST PERIOD. NORTH TO NORTHWEST SURFACE WINDS WILL GUST AS HIGH AS HIGH AS 35 KT ALONG AND EAST OF THE LARAMIE RANGE...AND 25 KT TO THE WEST THROUGH SUNSET. WINDS WILL DIMINISH AND SHIFT TO A WESTERLY DIRECTION LATER THIS EVENING. && .FIRE WEATHER... ISSUED AT 213 AM MDT SAT JUN 8 2013 FIRE WEATHER CONCERNS WILL CONTINUE TO BE MINIMAL THROUGH NEXT WEEK DUE TO THE CURRENT GREEN-UP AND NON CRITICAL FUEL MOISTURE. TEMPERATURES WILL BE MILD TODAY OVER THE CWA AND THEN WILL WARM TO WELL ABOVE NORMAL FOR MONDAY THROUGH WEDNESDAY. MINIMUM RELATIVE HUMIDITY VALUES WILL FALL TO BETWEEN 15 AND 20 PERCENT OVER THE LOWER ELEVATIONS THIS WEEKEND AND THEN BETWEEN 10 AND 15 PERCENT OVER THE LOWER ELEVATIONS OF MAINLY CARBON AND ALBANY COUNTIES EARLY NEXT WEEK. SOME SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE NORTH AND EAST PARTS OF THE CWA THIS MORNING. OTHERWISE... LITTLE OR NO PRECIPITATION IS EXPECTED FOR THE CWA FOR MUCH OF NEXT WEEK. A LARGE AREA OF HIGH PRESSURE IN THE UPPER ATMOSPHERE WILL BE OVER THE ROCKIES THE FIRST HALF OF NEXT WEEK AND WILL PRODUCE THE VERY WARM AND DRY WEATHER. NORTHWEST TO NORTH SURFACE WINDS WILL GUST AS HIGH AS 40 MPH OVER MUCH OF THE CWA TODAY BEHIND A COLD FRONT. LIGHTER WINDS ARE EXPECTED FOR SUNDAY AND MONDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...JAMSKI SHORT TERM...WEILAND LONG TERM...RUBIN AVIATION...JAMSKI FIRE WEATHER...WEILAND
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1051 PM MDT FRI JUN 7 2013 .SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT) ISSUED AT 315 PM MDT FRI JUN 7 2013 STRONG SHORTWAVE SHOWS UP NICELY ON WATER VAPOR IMAGERY IN SOUTHERN BRITISH COLUMBIA. SCATTERED SHOWERS AND ISOLATED TSTORMS HAVE DEVELOPED THIS AFTN...WITH THE BEST COVERAGE ACROSS SOUTHERN ALBANY COUNTY AND LARAMIE COUNTY. GUSTY WINDS AND BRIEF MODERATE RAIN HAS BEEN THE PRIMARY IMPACT FROM THESE STORMS SO FAR. LAPS ANALYSIS SHOWS 500-750 J/KG OF CAPE OVER MOST OF THE PLAINS WITH AROUND 25 KT OF 0-6 KM SHEAR. WITH THESE TYPE OF VALUES...CONCERN WILL STILL BE GUSTY WINDS AND PERHAPS SMALL HAIL...ALTHOUGH THE HAIL THREAT IS QUITE SMALL. THE HRRR MODEL CONTINUES TO INDICATE AN AREA OF SHOWERS PUSHING EASTWARD OVER CONVERSE/NIOBRARA COUNTIES AND INTO THE NORTHERN NEBRASKA PANHANDLE BETWEEN 00-12Z...SO INCREASED POPS A BIT IN THAT REGION. THIS IS WHERE THE STRONGEST ASCENT FROM THE SHORTWAVE WILL BE AS THE SYSTEM DROPS SOUTHEASTWARD FROM EASTERN MONTANA INTO SOUTH DAKOTA. SFC TROUGH MOVES EASTWARD AND OUT OF THE CWA BY LATE TONIGHT WITH PRESSURE RISES AND A FROPA. MID LEVEL CIRCULATION DEVELOPS OVER CENTRAL SOUTH DAKOTA BY SATURDAY AFTN WITH NORTHWESTERLY 700MB WINDS AROUND 30-35 KT IN THE NEBRASKA PANHANDLE. WHILE IT WILL BE A BREEZY DAY...BELIEVE THAT WIND GUSTS WILL STAY BELOW ADVISORY LEVELS AS THE AXIS OF HIGHEST 850-700MB WINDS ARE OVER WESTERN SOUTH DAKOTA. EXPANDED THE SLIGHT CHANCE POPS OVER THE PANHANDLE FOR SATURDAY MORNING WITH BOTH THE GFS AND NAM INDICATING LIGHT QPF IN THE MOIST NORTHWESTERLY MID LEVEL FLOW. DRY CONDITIONS WILL PREVAIL FROM SATURDAY AFTN THROUGH THE NIGHT AS A LARGE UPPER LEVEL RIDGE BUILDS IN THE INTERMOUNTAIN WEST. THE REAL WARM-UP WILL BEGIN LATE IN THE WEEKEND. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 315 PM MDT FRI JUN 7 2013 THE 12Z MEDIUM RANGE MODELS AND THEIR ENSEMBLES ARE CONSISTENT WITH THE OVERALL SYNOPTIC PATTERN. THE EASTERN GREAT PLAINS TROUGH WILL TRANSLATE EAST TOWARD THE OHIO VALLEY MONDAY. A RIDGE OVER THE GREAT BASIN SUNDAY WILL BEGIN TO BUILD AS IT CROSSES THE ROCKIES ON MONDAY. A SURFACE TROUGH WILL DEVELOP NEAR THE LARAMIE RANGE MONDAY AFTERNOON...WITH WEAK UPSLOPE FLOW. MODELS SHOW A WEAK DISTURBANCE PASSING ACROSS NORTHERN WYOMING DURING THE AFTERNOON...WHICH MAY TRIGGER ISOLATED TSTORMS OVER THE NORTHERN LARAMIE RANGE. A CLOSED LOW ENTERING SOUTHERN CALIFORNIA OPENS UP WITH A SHORTWAVE TROUGH LIFTING NORTHEAST THROUGH NEVADA AND UTAH TUESDAY AND INTO THE HIGH PLAINS TUESDAY NIGHT. BEST MOISTURE AND DYNAMICS FOR CONVECTION WILL SET UP FROM MONTANA THROUGH THE DAKOTAS. THERE ARE INDICATIONS THAT A CONVECTION MAY ORGANIZE INTO A COMPLEX AS THE WAVE MOVES INTO THE NORTHERN HIGH PLAINS TUESDAY NIGHT. THE SOUTHERN FRINGE OF THIS CONVECTION MAY IMPACT AREAS NORTH OF A LINE FROM DOUGLAS TO ALLIANCE...SO HAVE INCLUDED ISOLATED POPS. FOR THE MIDDLE OF THE WEEK...A TROUGH WILL AMPLIFY WEST OF THE GREAT BASIN...WITH THE DOWNSTREAM RIDGE BUILDING ONCE AGAIN OVER THE GREAT PLAINS. THIS UPPER LEVEL PATTERN WILL DEFLECT ANY SHORTWAVES FOR CONVECTION ACROSS THE NORTHERN ROCKIES AND PLAINS. THE RIDGE WILL BREAK DOWN AS THE TROUGH OUT WEST APPROACHES THE ROCKIES BY FRIDAY. THIS WILL ALLOW SOME MOISTURE TO ADVECT EAST ACROSS WYOMING. THE MODELS SHOW A FRONT DROPPING SOUTH ACROSS THE EASTERN PLAINS AND WESTERN PANHANDLE FRIDAY WITH WINDS SHIFTING TO THE NORTHEAST. ISOLATED TSTORMS WILL BE POSSIBLE NORTH OF A LINE FROM RAWLINS TO CHADRON. THE MAIN STORY WILL BE THE ABOVE NORMAL WARMTH...PARTICULARLY DURING THE EARLY PART OF NEXT WEEK. 700MB TEMPERATURES WILL BEGIN RISING SUNDAY WITH READINGS APPROACHING 16C. HIGHS WILL BE WELL INTO THE 80S FOR LOWER ELEVATIONS...WITH 60S AND 70S IN THE HIGH COUNTRY. WITH THE THERMAL RIDGE OVERHEAD MONDAY...700MB TEMPERATURES WILL BE AROUND 19C...WHICH EQUATES TO HIGHS IN THE UPPER 80S TO MID 90S FOR LOWER ELEVATIONS. THE MOUNTAINS WILL BE IN THE 60S AND 70S. THE THERMAL RIDGE WILL BE SITUATED EAST OF THE HIGH PLAINS TUESDAY. WEST-SOUTHWEST DOWNSLOPE FLOW WILL PUSH THE MERCURY INTO THE 80S AND 90S. RECORD HIGH TEMPERATURES MAY BE EQUALED OR EXCEEDED IN SOME AREAS MONDAY AND TUESDAY AFTERNOON. WEAK BACKDOOR FRONT OVER THE HIGH PLAINS WILL TRIM HIGH TEMPERATURES A FEW DEGREES WEDNESDAY AFTERNOON...BUT STILL REMAIN WARM. THERMAL RIDGE BUILDS OVER THE HIGH PLAINS THURSDAY WITH DOWNSLOPE WESTERLY FLOW WARMING TEMPERATURES FROM THE UPPER 80S TO MID 90S. FRONTAL PASSAGE FRIDAY WILL COOL HIGH TEMPERATURES ABOUT 10 DEGREES...AND CLOSER TO SEASONAL NORMALS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING) ISSUED AT 1048 PM MDT FRI JUN 7 2013 SOME SHOWER ACTIVITY AND A FEW THUNDERSTORMS WILL LINGER THROUGH TONIGHT...ESPECIALLY OVER EAST CENTRAL WYOMING AS A RELATIVELY POTENT SHORTWAVE APPROACHES THE AREA. THE CENTER OF THE SHORTWAVE WILL MOVE OVER EAST CENTRAL WYOMING AND THE NEBRASKA PANHANDLE AFTER SUNRISE SATURDAY. RAIN SHOWERS EXPECTED NEAR THIS WAVE. WINDS MAINLY ON THE LIGHT SIDE TONIGHT BUT GUSTY NORTHWEST WINDS EXPECTED BEHIND A COLD FRONT SATURDAY. && .FIRE WEATHER... ISSUED AT 315 PM MDT FRI JUN 7 2013 A RIDGE OF HIGH PRESSURE IS STILL EXPECTED TO BUILD ACROSS THE INTERMOUNTAIN WEST THIS WEEKEND INTO EARLY NEXT WEEK. TEMPERATURES WILL BE 10-15 DEGREES ABOVE NORMAL BY SUNDAY AND THEN 15-20 DEGREES ABOVE NORMAL BY EARLY NEXT WEEK. THE VERY WARM TEMPERATURES WILL CAUSE AFTERNOON HUMIDITIES TO DROP BELOW CRITICAL LEVELS INTO THE 10-15 PERCENT RANGE BY MONDAY AND TUESDAY AFTERNOONS. BREEZY WEST WINDS WILL ALSO OCCASIONALLY GUST TO 25-30 MPH MAINLY ALONG AND WEST OF THE LARAMIE RANGE...ESPECIALLY BY TUESDAY AFTERNOON. ALTHOUGH FUELS ARE STILL GREEN AND DO NOT SUPPORT LARGE FIRE GROWTH...THE WEATHER CONDITIONS COULD SUPPORT AN ELEVATED FIRE WEATHER THREAT BY EARLY NEXT WEEK. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...FINCH LONG TERM...JAMSKI AVIATION...LIEBL FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
416 AM EDT MON JUN 10 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 412 AM EDT MON JUN 10 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG EXTENDING FM NW ONTARIO THRU THE GREAT LKS TO THE MID ATLANTIC COAST. THERE ARE 2 CLOSED LOWS UPSTREAM...ONE MOVING THRU THE MID MS RIVER VALLEY AND ANOTHER OVER SASKATCHEWAN TO THE N OF MEAN RDG OVER THE WRN CONUS. A SHRTWV IS MOVING INTO NE MN BTWN THE 2 CLOSED LOWS AND GENERATING AN AREA RA OVER FAR NW LK SUP AND NE MN AS THE DPVA/ DEEP LYR QVECTOR CNVGC AHEAD OF THIS FEATURE INTERACTS WITH DEEP MSTR SHOWN ON THE 00Z INL RAOB. BUT SINCE THE DEEPER MSTR AND FORCING ASSOCIATED WITH THE CLOSED LO IN THE MID MS RIVER VALLEY ARE TO THE S OF UPR MI...THERE IS NO DYNAMIC SUPPORT FOR PCPN OVER UPR MI...WITH AN ABSENCE OF SGNFT RADAR RETURNS OVER THE AREA DESPITE MOCLDY SKIES. THE CLDS HAVE LIMITED THE DIURNAL FALL OF TEMP...WITH MOST PLACES REPORTING TEMPS IN THE 50S TO LO 60S EARLY THIS MRNG. SOME BREAKS IN THE CLDS ARE MOVING NE INTO UPR MI FM WI. THICKER CLDS/SOME ISOLD -SHRA ARE MOVING N THRU LWR MI. MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS ASSOCIATED WITH SHRTWV NOW MOVING THRU NE MN. TDAY...SHRTWV IN NE MN IS PROGGED TO LIFT NEWD INTO NW ONTARIO ON THE SE FLANK OF NEARLY STNRY CLOSED LO OVER SASKATCHEWAN. DPVA/H85-5 QVECTOR CNVGC ASSOCIATED WITH THIS FEATURE ARE PROGGED TO BRUSH THE NW CWA INTO THIS AFTN BEFORE THE SHRTWV LIFTS FARTHER TO THE NE AND GIVES WAY TO DNVA/DEEP LYR QVECTOR DVGC/MID LVL DRYING. MODELS SHOW BULK OF PCPN ACCOMPANYING THIS SHRTWV PASSAGE REMAINING TO THE NW OF EVEN THE KEWEENAW. SO OPTED TO CUT POPS TO NO HIER THAN SCHC THIS MRNG OVER THE LAND CWA. DID ADD SCHC POPS OVER THE E TO ACCOUNT FOR ISOLD -SHRA MOVING N THRU NRN LWR MI. EVEN AFT THE DYNAMIC SUPPORT SWINGS TO THE N THIS AFTN...BULK OF RECENT NUMERICAL GUIDANCE IS GENERATING QPF OVER MAINLY THE INTERIOR W HALF OF THE CWA AS DAYTIME HEATING DESTABILIZES THE ATMOSPHERE AND LK BREEZE BNDRYS PROVIDE SOME LLVL FOCUS. TENDED TO RAISE FCST MAX TEMPS A FEW DEGREES TO ACCOUNT FOR SOME BREAKS IN THE CLDS MOVING NE FM WI AND ABSENCE OF DYNAMIC FORCING OVER MOST OF THE FA. THE ONLY EXCEPTION WAS THE E... WHERE MORE CLDS STREAMING NWD THRU LWR MI MIGHT HOLD DOWN THE DIURNAL TEMP INCRS. EVEN THOUGH WARMING/DRYING ABV H6 WITH THE ARRIVAL OF THE NEGATIVE DYNAMICS SETS IN AFT 18Z AND WL LIMIT POTENTIAL FOR DEEP CNVCTN...MODIFIED NAM FCST SDNG FOR THE INTERIOR W FOR SFC T/TD OF 75/57 YIELDS SBCAPE NEAR 450 J/KG AND KINX OF 33. GOING CHC POPS/SCHC OF TS LOOKS TO BE IN PRETTY GOOD ORDER. TNGT...IN THE ABSENCE OF ANY DYNAMIC SUPPORT...EXPECT DIURNAL SHRA OVER MAINLY THE W HALF TO DIMINISH THIS EVNG WITH LOSS OF DAYTIME HEATING. ALTHOUGH ANOTHER SHRTWV IS PROGGED TO RACE EWD ALONG THE CNDN BORDER THRU TNGT IN THE FAST WLY FLOW ON THE SRN FLANK OF THE SASKATCHEWAN CLOSED LO AND APRCH THE NW CWA LATER WITH SOME DPVA/DEEP LYR QVECTOR CNVGC...FAIRLY DRY MID LVLS/LLVL ACYC FLOW/ ABSENCE OF ANY DIURNAL HEATING WL LIMIT ACCOMPANYING POPS... ESPECIALLY SINCE THE FOCUS OF THE ASSOCIATED FORCING IS FCST TO PASS TO THE N. DID RETAIN SOME CHC POPS OVER THE NW CWA TO ACCOUNT FOR THIS DISTURBANCE. OTRW...EXPECT SOME FOG TO FORM OVER THE INTERIOR WITH THE MID LVL DRYING/LGT WINDS...ESPECIALLY IN AREAS WHERE SOME RA MIGHT FALL THIS AFTN AND FURTHER MOISTEN THE LLVLS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 412 AM EDT MON JUN 10 2013 LARGER SCALE PATTERN BY TUESDAY INDICATES STRING OF TROUGHS ACROSS CANADA AND TROUGHING OVER NORTHWEST CONUS AND NORTHEAST CONUS. SHALLOW RIDGING IS ANCHORED OVER SOUTH CENTRAL CONUS. THROUGH REST OF THE WEEK TROUGHING OVER CANADA SPLITS WITH RIDGING ATTEMPTING TO BUILD INTO CANADIAN PRAIRIES. EVENTUALLY THIS RIDGE MOVES EAST INTO NORTHERN PLAINS AND UPPER GREAT LAKES BY START OF NEXT WEEKEND. YET ANOTHER TROUGH WILL THEN SWING BACK ACROSS UPPER LAKES TO CLOSE THE WEEKEND. OVERALL PATTERN WILL NOT BRING MUCH RAIN TO UPPER LAKES BUT IT ALSO SHOULD NOT BE THAT COLD EITHER AS BULK OF COLDER AIR STAYS LOCKED UP OVER WESTERN AND EASTERN CANADA CLOSER TO MORE PERSISTENT TROUGHING. TEMPS INLAND FROM LK SUPERIOR AND NEAR LK MICHIGAN MOST DAYS WILL BE AT OR ABOVE NORMAL. TEMPS ALONG LK SUPERIOR WILL BE AT OR SLIGHTLY BLO NORMAL MOST OF THE TIME SINCE PREVAILING WINDS WILL BE ONSHORE. WARMEST DAYS WILL BE TUESDAY AND AGAIN ON SATURDAY WITH MOST AREAS WELL INTO THE 70S. COOLEST DAY THIS WEEK FOR ALL AREAS SHOULD BE ON THURSDAY WHEN TEMPS ALONG LK SUPERIOR WILL LIKELY STAY IN THE 50S. WEAK SHORTWAVE TROUGH AND POCKET OF H85-H7 MOISTURE SWINGS ACROSS WESTERN AND CENTRAL CWA ON TUESDAY MORNING THEN OVR EASTERN CWA DURING AFTN HOURS. THOUGH SHARPEST LIFT IN FORM OF H85-H7 Q-VECTOR CONVERGENCE IMPACTS LK SUPERIOR AND ISLE ROYALE/KEWEENAW PENINSULA THROUGH MIDDAY...RIBBON OF LIFT CROSSES REST OF CWA AS WELL. WEAK FORCING AND SUBTLE MOISTENING POINTS TO LOW CHANCE POPS. BUT...KIND OF SIMILAR TO TODAY...COULD SEE ISOLD DAYTIME SHRA AND EVEN TSRA AS SFC CAPES POP UP TO 300-500J/KG OVR SCNTRL IN THE AFTN. H7-H5 WINDS 45-55KT RESULTING IN DEEP LAYER SHEAR OVR 30 KTS. DO NOT EXPECT THERE TO BE ENOUGH INSTABILITY TO TAKE ADVANTAGE OF THE STRONGER SHEAR THOUGH SO DO NOT EXPECT ANY STRONG STORMS. DEEP DRYING IN H7 LAYER QUICKLY ENDS ANY SHRA/TSRA BY LATE TUE AFTN. H7 DRYING AND NEUTRAL HEIGHTS SHOULD KEEP CONDITIONS DRY THROUGH REST OF TUESDAY NIGHT. ON WEDNESDAY...SHORTWAVE TROUGH SLIDES FROM ROCKIES TOWARD UPPER MISSISSIPPI RIVER VALLEY. SFC LOW/WARM FRONT SET UP FROM NEB INTO NORTHERN IL WHILE H85 WARM FRONT IS NOT MUCH FARTHER THAN THAT. EDGE OF H7 MOISTURE MIGHT MAKE IT INTO NORTHERN WI...BUT SINCE 1-6KM MUCAPE IS BARELY INTO SOUTHERN MN AND CNTRL WI...HAVE HARD TIME THINKING THAT THE INCREASE IN H7 MOSITURE WOULD RESULT IN NOTHING MORE THAN A FEW SPRINKLES OUT OF A SCT-BKN MID CLOUD DECK. NOT WORTH PUTTING ANY POPS INTO SOUTHERN CWA. OTHER THING TO WATCH ON WEDNESDAY IS SHORTWAVE TIED INTO NORTHERN STREAM TROUGH PUSHING INTO ONTARIO. TREND IS FOR WAVE TO BE STRONGER...BUT MAJORITY OF MODELS KEEP WAVE ON WNW-ESE TRACK OVER NORTHERN LK SUPERIOR IN THE MORNING AND OVER ONTARIO EAST OF SAULT STE MARIE BY AFTN. SFC BASED INSTABILITY AND STEEPER H7-H5 LAPSE RATES SHOULD SPUR ON SCATTERED SHRA/TSRA NORTH AND EAST OF LK SUPERIOR WITH DAYTIME HEATING. ONLY THE GEM-NH SHOWS THE WAVE DIGGING ENOUGH SOUTH TO HAVE ANY QPF OVR UPR MICHIGAN THOUGH AND THAT IS ONLY OVR FAR EAST CWA. MAJORITY RULES FOR NOW SO HAVE NOT PUT ANY POPS IN OVER THE EAST. MAX TEMPS MAY SHOW VARIATION CLOSER TO LK SUPERIOR AS LAKE COOLING IS ENHANCED BY AFTN WITH DEVELOPING NORTH GRADIENT FLOW. MAY SEE TEMPS QUICKLY RISE WEDNESDAY MORNING CLOSER TO LK SUPERIOR THEN FALL OFF IN THE AFTN. FARTHER INLAND...EXPECT ANOTHER DAY WITH HIGHS INTO THE 70S. SHORTWAVE PASSAGE RESULTS IN H85-H7 WINDS VEERING MORE NORTH LATER WEDNESDAY NIGHT INTO THURSDAY. H85 THERMAL TROUGH ALSO PRESENT. NOT EXPECTING ANY SHRA AS FORCING IS MINIMAL...BUT MAY SEE DECENT CLOUD COVER IN THE MORNING. BY AFTN...H85 RH PROGS SHOWING LAKE STABILIZING SIGNAL WITH MINIMUM RH SHOWING UP OVR LK SUPERIOR AFT 18Z. PROBABLY WILL SEE CLEARING DEVELOP CLOSER TO LK SUPERIOR AND OVER EAST DUE TO STABILIZING FLOW. EVEN WITH CLEARING WILL BE COOL DAY ALONG LK SUPERIOR AS MOST LOCATIONS STAY IN THE 50S WITH STIFF NORTHERLY WINDS. INLAND TEMPS WILL BE IN THE UPR 60S TO PERHAPS LOWER 70S. HIGH PRESSURE BUILDS ACROSS THURSDAY NIGHT THROUGH FRIDAY AND NOW EVEN THROUGH MOST OF FRIDAY NIGHT. MOSTLY CLEAR SKIES WILL PREVAIL AND GIVEN TREND OF HIGH STAYING AROUND LONGER...FRIDAY NIGHT NOW LOOKING GENERALLY FREE OF ANY SHRA/TSRA EXCEPT FAR WEST CWA. WEEKEND FORECAST MUDDLED AS MID CONUS RIDGE FLATTENS OUT FROM NORTHERN PLAINS TO UPPER GREAT LAKES. STRONGER SHORTWAVE TROUGHS CUTTING THROUGH THE RIDGE FORECAST TO BE OVR CNTRL CANADA AND OVR THE MIDDLE MISSISSIPPI RIVER VALLEY. TALKING DAY 6 AND 7 SO HARD TO GET TOO HUNG UP ON THESE TYPE OF DETAILS YET. OVERALL THEME THOUGH IS SLOWER ARRIVAL OF SHRA/TSRA CHANCES AND/OR A GENERAL LACKING FOCUS FOR SHRA/TSRA. CONSENSUS POPS IN THE LOW CHANCE RANGE USED BUT DID PULL POPS OVER EASTERN CWA ON SATURDAY AS THAT AREA IS IN CLOSER PROXIMITY OF STUBBORN SFC RIDGING. TEMPS FOR NEXT WEEKEND SHOULD BE SIMILAR TO READINGS THIS WEEK WITH HIGHS MAINLY IN THE 70S AND POSSIBLY WARMER IF THERE ARE LESS CLOUDS/SHRA/TSRA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 126 AM EDT MON JUN 10 2013 E TO SE PREVAILING FLOW SHOULD HELP MAINTAIN SOMEWHAT DRIER AIR AT THE LOW-LEVELS...KEEPING CONDITIONS VFR THROUGH MOST OF THE PD DESPITE PCPN. WITH RAINFALL WETTING THE GROUND MORE SO AT KIWD...THERE IS THE POTENTIAL FOR LOWER CLOUDS/FOG TO FORM OVERNIGHT. HOWEVER...SINCE LOW-LEVEL WINDS REMAIN FROM A DOWNSLOPING SE DIRECTION...POTENTIAL APPEARS MINIMAL. EARLY MON AFTN...DAYTIME HEATING MAY BEGIN TO POP A FEW SHRA...ESPECIALLY AROUND KIWD. BY LATE MON EVENING...THERE COULD BE A POTENTIAL FOR PATCHY FOG...ESPECIALLY AT KCMX WHERE HIGHER DEWPOINTS ALONG LAKE SUPERIOR MAY BE MORE CONDUCIVE FOR FOG FORMATION && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 AM EDT MON JUN 10 2013 AS LO PRES IN THE LOWER GREAT LAKES SHIFTS SLOWLY TO THE E TODAY... EXPECT E-SE WINDS UP TO 20 KTS TO SLOWLY DIMINISH W-E WITH THE WEAKENING PRES GRADIENT AND UNDER 15 KTS TONIGHT. DID MAINTAIN PATCHY FOG OVER MUCH OF THE WESTERN LAKE WHERE SOME SHOWERS HAVE FURTHER MOISTENED THE LOW LEVELS. THE WEAK PRES GRADIENT WILL PREVAIL THRU FRI...SO PLAN ON WINDS UNDER 15 KTS TUE THRU FRI. COULD BE A BRIEF PERIOD OF STRONGER WINDS...UP TO 20 KTS IN GUSTS...LATE WEDNESDAY NIGHT AND THURSDAY MORNING. RELATIVELY MOIST AIR OVER THE STILL CHILLY LAKE WATERS WILL RESULT IN LINGERING FOG PATCHES UNTIL DRIER AIR ARRIVES ON FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...VOSS MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
128 AM EDT MON JUN 10 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 412 PM EDT SUN JUN 9 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE OVER NW IA DOWNSTREAM OF A RIDGE OVER THE WRN CONUS. ANOTHER SHORTWAVE IS MOVING ACROSS ND AND ADJACENT SASKATCHEWAN/MANITOBA IN ASSOCIATION WITH A BROAD CLOSED MID LEVEL LOW OVER SW CANADA. SHORTWAVE OVER IA HAS MANAGED TO SWING A BAND OF SHRA N INTO WRN UPPER MI TODAY. SHRA HAVE BEEN SUPPORTED BY LOW/MID LEVEL FRONTOGENESIS AND PROBABLY SOME RIGHT ENTRANCE UPPER DIVERGENCE FROM JET STREAK EXTENDING FROM LAKE SUPERIOR TO NEW ENGLAND. ERN EDGE OF SHRA AREA HAS BATTLED ANTECEDENT DRY AIR MASS AT THE LOW/MID LEVELS PER 12Z KGRB/KAPX SOUNDINGS. IT APPEARS SPRINKLES HAVE REACHED AS FAR E AS MEMONINEE AND DICKINSON COUNTIES TODAY. WITH RECENT RADAR IMAGERY SHOWING ERN EDGE OF PCPN BAND FALLING APART AS IT MOVES FARTHER INTO DRIER AIR MASS...WILL SHOW A DIMINISHING POP TREND OVER THE W DURING THE NEXT SEVERAL HRS. SPRINKLES MAY GET AS FAR E AS WRN MARQUETTE COUNTY. OTHERWISE...WITH SHORTWAVE OVER IA DRIFTING ESE INTO IL TONIGHT...THIS DISTURBANCE IS NOT LIKELY TO PROVIDE ANY FORCING FOR PCPN OVER UPPER MI. IN FACT...PER QVECTORS...MODELS INDICATE A FAIRLY PRONOUNCED SPLIT IN DEEP LAYER FORCING DEVELOPING OVER UPPER MI BTWN THE WAVE MOVING INTO IL AND THE AFOREMENTIONED SHORTWAVE CURRENTLY OVER ND THAT WILL BE MOVING INTO FAR NE MN/NRN ONTARIO TONIGHT. THIS WILL LEAVE MUCH OF THE FCST AREA IN AN AREA OF LITTLE/NO DYNAMIC FORCING TONIGHT. SO...FCST TONIGHT WILL RETAIN THE IDEA OF HIGHER POPS OVER THE NW... ESPECIALLY TOWARD ISLE ROYALE...AND LOW CHC/SCHC POPS ELSEWHERE... EXCEPT FOR THE E WHICH SHOULD REMAIN DRY TONIGHT UNDER LINGERING MID/UPPER RIDGING. A NUMBER OF THE HIGHER RES MODELS SHOW REMNANTS OF CONVECTION DEVELOPING IN WRN LWR MI ROTATING NW INTO SCNTRL UPPER MI THIS EVENING. WILL BE INTERESTING TO SEE IF THAT DOES HAPPEN. SHORTWAVE THAT REACHES NE MN/ADJACENT NRN ONTARIO LATE TONIGHT WILL CONTINUE EASTWARD MON. WAVE WILL SUPPORT BETTER PCPN CHANCES ACROSS WRN AND NRN LAKE SUPERIOR INTO PORTIONS OF NW UPPER MI MON MORNING. MUCH OF THE FORCING WITH WAVE WILL THEN SHIFT N AND E OF THE AREA AS THE AFTN WEARS ON. ATTENTION THEN TURNS TO POTENTIAL FOR AFTN CONVECTION. NAM SHOWS MLCAPE INCREASING TO 150-500J/KG IN THE AFTN WITH THE GREATEST INSTABILITY OVER THE INTERIOR W HALF OF THE FCST AREA. THE GFS HAS SIMILAR VALUES...BUT ITS INSTABILITY IS CONFINED TO JUST THE W HALF OF UPPER MI. WITH THE POSSIBILITY OF THE TAIL END OF DEPARTING DEEP LAYER FORCING STILL SKIRTING THE AREA IN THE AFTN...AVBL INSTABILITY IS CERTAINLY SUFFICIENT FOR A MENTION OF SHRA OVER MUCH OF THE AREA IN THE AFTN (CHC POPS OVER THE INTERIOR W HALF AND SCHC E). CONVECTION OVER THE W SHOULD BE FURTHER AIDED BY LAKE BREEZE CONVERGENCE. OPTED TO INCLUDE SCHC THUNDER MENTION OVER THE INTERIOR W HALF WHERE INSTABILITY WILL BE MAXIMIZED. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 412 PM EDT SUN JUN 9 2013 DIURNALLY DRIVEN RAIN SHOWERS AND THUNDERSTORMS ACROSS THE INTERIOR WEST AND CENTRAL AREAS WILL DIMINISH MONDAY NIGHT AS WE LOSE HEATING OVERNIGHT. MEANWHILE...LOW PRESSURE WILL MOVE FROM SASKATCHEWAN INTO ONTARIO BY TUESDAY EVENING. THIS WILL BRING A SHORTWAVE ACROSS UPPER MICHIGAN TUESDAY. ADDITIONALLY...LOW PRESSURE WILL MOVE FROM THE OHIO VALLEY TOWARDS THE NEW ENGLAND STATES. HIGH PRESSURE CENTERED OVER TEXAS WILL KEEP A RIDGE ACROSS MUCH OF THE CENTRAL U.S. FOR THIS TIME PERIOD. AS IT IS...UPPER MICHIGAN WILL BE UNDER THE INFLUENCE OF WEAK RIDGING AND A PASSING SUBTLE SHORTWAVE TUESDAY. THOUGH THERE WILL BE MOISTURE LINGERING AROUND/PWATS UP TO 115 PERCENT OF NORMAL...PRECIPITATION WILL BE LIMITED BY THIS RIDGE OVER LAND. HAVE SLIGHT CHANCE POPS MOVING WEST TO EAST ACROSS THE CWA THROUGH THE DAY ON TUESDAY. THE BEST FORCING WITH THIS SHORTWAVE IS PRIMARILY NORTH OF LAKE SUPERIOR...SO CHANCE POPS ARE ACROSS THE WESTERN AND NORTHERN PORTIONS OF THE LAKE WITH THE SHORTWAVE. ADDITIONAL SHOWERS COULD POP UP ALONG THE LAKE BREEZE BOUNDARIES TOWARDS THE AFTERNOON...SO KEPT SLIGHT CHANCE POPS IN THIS AREA UNTIL 00Z. AS FOR WEDNESDAY...WITH HIGH PRESSURE SETTING UP ACROSS THE CENTRAL U.S. EXPECT MCS DEVELOPMENT TO OCCUR ALONG THE RIDGE BOUNDARY AS SEVERAL SHORTWAVES SLIDE THROUGH. THIS WILL REMAIN SOUTH OF UPPER MICHIGAN HOWEVER...LIKELY OVER CENTRAL/LOWER WI. THE UPPER LOW THAT BROUGHT THE SHORTWAVE THROUGH UPPER MI ON TUESDAY WILL CONTINUE TO GENERATE PRECIPITATION...OVER PRIMARILY ONTARIO AND QUEBEC. WITH RIDGE EXPANDING NORTHWARD DO NOT EXPECT ANYTHING MORE THAN SOME SCATTERED CLOUD COVER OVER UPPER MI. THE RIDGE OF HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES REGION FOR THURSDAY AND MUCH OF FRIDAY...WHICH WILL KEEP THE WEATHER QUIET. WITH COOL NORTHERLY WINDS OFF THE LAKE ON THURSDAY AND MIXING TO AROUND 950MB IN MOST LOCATIONS EXPECT HIGH TEMPERATURES TO RANGE FROM THE MID 60S TO LOW 70S...WITH THE WARMER TEMPERATURES INLAND FROM LAKE SUPERIOR. REGIONS CLOSEST TO THE LAKES COULD SEE SLIGHTLY LOWER TEMPERATURES. ON FRIDAY AFTERNOON CLOUD COVER IN THE WEST INCREASES WITH AN APPROACHING AREA OF LOW PRESSURE. STILL EXPECT MOST AREAS TO EXPERIENCE FULL DAYTIME HEATING THOUGH...AND WITH BETTER MIXING TO THE 850MB LEVEL/TEMPS AROUND 12-14C AND DEVELOPING SOUTHERLY WINDS EXPECT HIGHS TO REACH INTO THE MID 70S AWAY FROM LAKE SUPERIOR. FRIDAY NIGHT-SUNDAY LOW PRESSURE OVER MANITOBA WILL CROSS EASTWARD INTO QUEBEC...JUST NORTH OF LAKE SUPERIOR. CORRESPONDING COLD FRONT WILL CROSS UPPER MICHIGAN SATURDAY AFTERNOON INTO SUNDAY EVENING. WITH SOUTHERLY WINDS BRINGING MORE MOISTURE TO THE AREA/DEWPOINTS NEARING 60F/ AND PASSAGE OF THE COLD FRONT...EXPECT SHOWERS AND A FEW THUNDERSTORMS TO SPREAD EASTWARD ACROSS THE CWA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 126 AM EDT MON JUN 10 2013 E TO SE PREVAILING FLOW SHOULD HELP MAINTAIN SOMEWHAT DRIER AIR AT THE LOW-LEVELS...KEEPING CONDITIONS VFR THROUGH MOST OF THE PD DESPITE PCPN. WITH RAINFALL WETTING THE GROUND MORE SO AT KIWD...THERE IS THE POTENTIAL FOR LOWER CLOUDS/FOG TO FORM OVERNIGHT. HOWEVER...SINCE LOW-LEVEL WINDS REMAIN FROM A DOWNSLOPING SE DIRECTION...POTENTIAL APPEARS MINIMAL. EARLY MON AFTN...DAYTIME HEATING MAY BEGIN TO POP A FEW SHRA...ESPECIALLY AROUND KIWD. BY LATE MON EVENING...THERE COULD BE A POTENTIAL FOR PATCHY FOG...ESPECIALLY AT KCMX WHERE HIGHER DEWPOINTS ALONG LAKE SUPERIOR MAY BE MORE CONDUCIVE FOR FOG FORMATION && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 PM EDT SUN JUN 9 2013 AS LOW PRES OVER NW IA DRIFTS E...EXPECT EASTERLY WINDS UP TO AROUND 20KT ACROSS LAKE SUPERIOR THRU MON. LOCALLY HIGHER WINDS TO AROUND 25KT SHOULD OCCUR OVER THE FAR W THRU THIS EVENING DUE TO COASTAL CONVERGENCE. WITH SOME RAIN FALLING OVER THE WRN PART OF THE LAKE... PATCHY FOG MAY DEVELOP TONIGHT OVER THE W. WEAK HIGH PRES WILL RETURN AND BRING GENERALLY LIGHT WINDS FOR TUE THRU FRI. MUCH OF THAT PERIOD WILL SEE WINDS AOB 15KT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...MCD AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DULUTH MN
1224 AM CDT MON JUN 10 2013 .AVIATION...06Z TAF ISSUANCE... RAIN AND DRIZZLE SHOULD TAPER OFF BEFORE 08Z ACROSS ALL AREA TERMINALS WITH FOG AND LOW MVFR/IFR CIGS DEVELOPING DURING THE OVER NIGHT AND EARLY MONDAY MORNING HOURS. CIGS WILL GRADUALLY LIFT THROUGH THE LATE MORNING AND EVENTUALLY BECOME VFR BY THE EARLY AFTERNOON ACROSS THE ENTIRE REGION. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE DAY. THE NEXT WEAK FRONT MOVES IN FROM THE NW LATE MON EVENING AND BRING VCSH TO HIB AND INL...WITH ADDITIONAL SLIGHT CHANCES FOR RAIN AFTER 06Z TO THE REMAINING TERMINALS. && .PREV DISCUSSION... /ISSUED 620 PM CDT SUN JUN 9 2013/ AVIATION...00Z TAF ISSUANCE... RAIN SHOWERS AND/OR -DZ WILL CONTINUE THROUGH THIS EVENING WITH CONDITIONS DRYING OUT AT BRD FIRST...THEN HIB...DLH...HYR AND INL. WILL LIKELY SEE IFR FOG DEVELOP TONIGHT...WITH LOCALIZED AREAS OF LIFR VSBYS LATE TONIGHT/EARLY MON MORNING. CIGS WILL GRADUALLY LIFT THROUGH THE MORNING HOURS...WITH HIGH-END MVFR CIGS BY THE EARLY AFTERNOON...AND VFR BY THE MID TO LATE AFTERNOON. PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ SHORT TERM.../NOW - MONDAY/ THE FOCUS IS ON THE WIDESPREAD RAIN COVERING MUCH OF THE FORECAST AREA THIS AFTERNOON...AND HOW THAT WILL CONTINUE AND LINGER THROUGH TONIGHT. THE MODELS ARE IN FAIRLY GOOD AGREEMENT...BUT I HAVE AND CONTINUE TO LEAN ON THE HRRR SIMULATED REFLECTIVITY AS FAR TIMING OF THE PCPN THROUGH THIS EVENING GOES SINCE THE HRRR SEEMS TO BE DOING PRETTY WELL. AT 300PM/2000Z...HIGH PRESSURE STRETCHED FROM NEW YORK INTO THE EASTERN GREAT LAKES AND ONTARIO. A LOW PRESSURE SYSTEM WAS CENTERED NEAR NW IOWA...AND ANOTHER LOW PRESSURE SYSTEM IN CENTRAL SASKATCHEWAN. A TROUGH BOUNDARY EXTENDED FROM THE SASKATCHEWAN LOW THROUGH THE EASTERN DAKOTAS TO THE IOWA LOW. PLENTY OF MOISTURE WAS SURGING NORTHWARD AHEAD OF THE IOWA LOW AND THE TROUGH IN THE EASTERN DAKOTAS. THERE WAS WIDESPREAD LIGHT TO MODERATE RAIN ACROSS THE NORTHLAND. THERE WERE EASTERLY WINDS OF 5 TO 15 MPH. TEMPERATURES RANGED FROM THE MID TO LOWER 60S ACROSS THE SE AND FAR N FORECAST AREA...WHILE THE REST OF THE FORECAST AREA HAD TEMPERATURES IN THE LOW TO UPPER 50S DUE TO THE RAIN AND COOL WINDS OFF LAKE SUPERIOR. THROUGH TONIGHT...THE LOW IN NW IOWA WILL MOVE EAST TO NEAR SOUTHERN LAKE MICHIGAN BY LATE TONIGHT....WHILE THE TROUGH IN THE EASTERN DAKOTAS WILL SHIFT EAST TO THE EASTERN FORECAST AREA. HIGH PRESSURE WILL MOVE INTO THE PLAINS IN THE WAKE OF THE LOW AND TROUGH. THE RAIN SHOWERS ACROSS THE NORTHLAND SHOULD GENERALLY LIFT NORTH AND EASTWARD THIS AFTERNOON AND THEN GRADUALLY DIMINISH FROM WEST TO EAST TONIGHT. THE WINDS WILL WEAKEN AND BECOME NEGLIGIBLE LATER TONIGHT...MAKING FOG LIKELY FOR LATE TONIGHT AND INTO TOMORROW MORNING. OVERNIGHT LOWS SHOULD BE IN THE UPPER 40S TO MID 50S. MONDAY...WEAK HIGH PRESSURE WILL MOVE INTO THE NORTHLAND. THIS HELP KEEP MOST OF THE NORTHLAND DRY...BUT THERE COULD BE LINGERING RAIN SHOWERS/STORMS ACROSS THE EASTERN FORECAST AREA...AS WELL AS AFTERNOON SHOWERS/STORMS ACROSS THE NW FORECAST AREA THAT WOULD BE RELATED TO LOW PRESSURE MOVING ACROSS SOUTHERN MANITOBA. I HAVE SOME UNCERTAINTY ABOUT THE TEMPERATURE FORECAST. I RAISED THE FORECAST IN SOME AREAS BASED ON A BLEND OF THE LATEST GUIDANCE...BUT I THINK IT COULD BE EVEN WARMER IF THE NORTHLAND GETS ENOUGH SUNSHINE IN THE AFTERNOON. I SIDED A BIT ON THE CONSERVATIVE SIDE...ESPECIALLY SINCE THERE MAY BE MORNING FOG AND WE WILL HAVE TO SEE HOW WELL IT CLEARS CONSIDERING LITTLE WIND TO HELP MIX IT OUT. HOWEVER...IT AT LEAST LOOKS LIKE THE NORTHLAND WILL FINALLY GET SOME NEAR NORMAL TEMPERATURES AFTER COOLER THAN NORMAL WEATHER FOR SUCH A LONG TIME. LONG TERM.../MONDAY NIGHT - SUNDAY/ SURFACE HIGH PRESSURE WITH WEAK MID LEVEL RIDGING WILL MAKE A RETURN MONDAY NIGHT/TUESDAY. MEANWHILE THE A SHORT WAVE WILL TRACK EAST ALONG THE INTERNATIONAL BORDER AND INTO THE MN ARROWHEAD...SWEEPING A TROUGH OVER THE NORTHLAND. LATEST NAM BUFR SOUNDINGS SHOW VERY DRY PROFILES WITH RAPIDLY FALLING PWATS THROUGH TUESDAY MORNING...SO HAVE LIMITED POPS TO NRN ZONES...MAINLY MONDAY NIGHT...AND GONE WITH A DRY FCST OR JUST MENTION OF SPRINKLES ELSEWHERE TUESDAY. LONG TERM MODELS ARE IN GOOD OVERALL AGREEMENT THAT A H50 RIDGE AMPLIFIES OVER THE UPPER MIDWEST LATE THROUGH THE END OF THE WEEK WITH HIGH PRESSURE BUILDING OVER ONTARIO AND THE WESTERN GREAT LAKES. TEMPERATURES IN EXTENDED LOOK TO TREND TOWARDS MORE SEASONABLE VALUES WITH HIGHS IN THE 70S TO NEAR 80. HAVE KEPT A DRY FCST WED/THURS WITH GRADUALLY INCREASING POPS FROM THE WEST FRIDAY/SATURDAY AHEAD OF A COLD FRONT. && .POINT TEMPS/POPS... DLH 53 76 53 75 / 10 10 10 0 INL 53 75 52 75 / 40 10 10 10 BRD 56 79 57 76 / 10 10 10 10 HYR 55 80 56 77 / 10 10 10 10 ASX 50 76 51 72 / 10 10 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ AVIATION...GSF
AREA FORECAST DISCUSSION
NWS GLASGOW MT
405 AM MDT MON JUN 10 2013 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH WEDNESDAY... SHOWER ACTIVITY VERY EARLY THIS MORNING CONTINUES ACROSS EASTERN SECTIONS OF THE FORECAST AREA. MUCH OF THE MODEL GUIDANCE HAS THIS PUSHING OUT BY 12Z HOWEVER...RECENT RUNS OF THE HRRR HAVE KEPT SPOTTY SHOWERS AROUND FOR A FEW MORE HOURS. THUS...TO COVER THIS POTENTIAL INSERTED A SLIGHT CHANCE POPS MENTION INTO THE GRIDS IN THE EASTERN ZONES. ANY SHOWERS LEFT OVER FROM EARLY THIS MORNING SHOULD QUICKLY MOVE OUT AND BECOME REPLACED BY SUNNY SKIES BY THE AFTERNOON AS NORTHEAST MONTANA BECOMES INFLUENCED BY THE NORTHERN PERIPHERY OF AN UPPER LEVEL RIDGE. THIS WILL INDUCE LARGE SCALE SUBSIDENCE AND PREVENT ANY ADDITIONAL SHOWER ACTIVITY FROM FLARING UP. WILL EXPECT SEASONABLE TEMPERATURES AS WELL WITH THE EARLY JUNE SUNSHINE GOING TO WORK AND RISING 500MB HEIGHTS WITH THE RIDGING BUILDING IN. MONDAY NIGHT...A REGIME OF SOUTHWEST FLOW ALOFT BECOMES ESTABLISHED OVER NORTHEAST MONTANA AS AN UPPER LEVEL SHORTWAVE FEATURE TRANSLATES INTO THE AREA. PVA OUT AHEAD OF THIS WAVE AND UPPER LEVEL DIFFLUENCE WILL PROMOTE FORCED VERTICAL ASCENT. LOW LEVEL SOUTHEASTERLY FLOW WILL ALSO BRING MOISTURE INTO THE FORECAST AREA. MODELS CONTINUE TO HAVE DISAGREEMENT HOWEVER ON THE POTENTIAL FOR SHOWERS/STORMS MONDAY NIGHT INTO TUESDAY APPROACHING FROM THE SOUTH. THE GFS HAS A BAND IN THE SOUTHERN ZONES OVERNIGHT...BUT HAS IT DISSIPATING OVER THE AREA ON TUESDAY. THE ECMWF IS MUCH MORE SUPPORTIVE OF CONVECTION AND GIVEN THE OVERALL PATTERN AND ARGUMENTS ABOVE LEANED TOWARD THIS SOLUTION FOR NOW WILL NOTE THAT THE LATEST ECMWF INDICATES GOOD SURFACE CONVERGENCE IN THE SOUTHWESTERN AND CENTRAL ZONES. THIS LIKELY CORRESPONDS TO A THERMAL TROUGH THAT EXTENDS FROM A SURFACE LOW EXPECTED TO BE LOCATED OVER NORTHEAST WYOMING AT THIS TIME. SHOULD CONVECTION PUSH INTO THE CWA DURING THE DAY ON TUESDAY...THIS TROUGH AXIS COULD SERVE AS A FOCAL POINT FOR ADDITIONAL CONVECTION INITIATION. WEDNESDAY...AN ADDITIONAL VIGOROUS SHORTWAVE APPROACHES FROM THE SOUTHWEST WHICH WILL BRING THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS WITH IT. AS IT PUSHES INTO A NICE THETA-E RIDGE THAT SETS UP ACROSS THE SOUTHWESTERN ZONES. THE LATEST 00Z MODEL GUIDANCE INDICATES THAT THE BEST CHANCES FOR CONVECTION INITIATION WOULD BE ACROSS WESTERN/CENTRAL ZONES. THE LATEST ECMWF HAS UPWARDS OF 1500 J/KG OF CAPE...WITH THE GFS A LITTLE MORE ROBUST. FORECAST SOUNDINGS ALSO SHOW A NICE VEERING WIND PROFILE INDICATING PLENTY OF DIRECTIONAL WIND SHEAR. THIS WILL COMBINE WITH UPPER LEVEL DIFFLUENCE AND LOW LEVEL MOISTURE TO PRODUCE A GOOD POTENTIAL FOR CONVECTION. GIVEN PRECIPITABLE WATER VALUES OF OVER AN INCH...LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. THE ECMWF SOLUTION IS MUCH FURTHER WEST...WITH THE GFS MORE AGGRESSIVE BRINGING THE PRECIPITATION CHANCES THROUGH MOST OF THE CWA BY 00Z THURSDAY. GIVEN THESE DIFFERENCES...WAS NOT CONFIDENT ENOUGH JUST YET TO INSERT A MENTION OF HEAVY RAIN INTO THE GRIDS JUST YET...BUT A WETTING RAIN IS CERTAINLY POSSIBLE WITH THESE STORMS...ESPECIALLY IN THE WEST. WILL LET THE DAY SHIFT EVALUATE THAT MORE CLOSELY AND SEE IF THERE IS DECENT MODEL CONTINUITY OR IF SOLUTIONS ARE LINING UP BETTER. AM CONCERNED ABOUT CAPPING INVERSION IN THE CENTRAL AND EASTERN ZONES AS THERE IS UPWARDS OF 200-400 J/KG OF CIN PRESENT IN SOME OF THE GUIDANCE. THIS LENDS FURTHER SUPPORT TO THE IDEA OF THE BEST CHANCES BEING ACROSS THE WEST...AT LEAST INITIALLY. NOTE THAT BEST LOW LEVEL CONVERGENCE ACROSS THE WESTERN ZONES DURING THE DAY ON WEDNESDAY IS DEPICTED TO SHIFT EASTWARD BY THE LATE AFTERNOON. THUS...STORMS MAY INITIATE ACROSS THE WEST AND THEN PUSH EASTWARD. IT IS NOTEWORTHY THAT GIVEN HEAVY RAINFALL POTENTIAL WITH ANY STORMS THAT DO DEVELOP...FUTURE SHIFTS WILL NEED TO EVALUATE THE FLOODING POTENTIAL DUE TO RECENT RAINFALL OVER THE LAST COUPLE OF WEEKS. MALIAWCO .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... THE EXTENDED WITH THE 00Z SUITE OF MODELS IN KEEPS THE AREA IN A VERY TYPICAL JUNE PATTERN THROUGH THE WHOLE PERIOD. WHICH LEADS TO A HIGH LEVEL OF PREDICTABILITY OF THE PATTERN...HOWEVER IT ALL WILL BE IN THE TIMING OF INDIVIDUAL WAVES MOVING THROUGH THE FLOW FOR THUNDERSTORM CHANCES. CLIMO POP FOR THIS TIME OF YEAR IS AT ITS HIGHEST WITH CHANCE LEVEL POPS. WEDNESDAY NIGHT...SOUTHWEST FLOW ALOFT AND SURFACE TROUGH TO THE WEST SHOULD SET UP FOR A FEW THUNDERSTORMS ACROSS THE AREA. UPPER LEVEL SUPPORT IS NOT THAT GREAT FOR SEVERE TYPE CONVECTION. THURSDAY-THURSDAY NIGHT BRINGS MORE OF THE SAME...EC DOES HINT THAT WE COULD GET A LITTLE JET DYNAMICS TO HELP OUT FOR A CHANCE FOR SOME STRONGER THUNDER. FRIDAY-FRIDAY NIGHT...SURFACE TROUGH PUSHES EAST WITH GOOD DRYING ALOFT SO WILL RELAX BACK BELOW CLIMO FOR POPS. SATURDAY-SATURDAY NIGHT...PREFER THE EC OVER THE GFS KEEPING NORTHEAST MONTANA MOSTLY DRY...STILL CYCLONIC FLOW COULD HAVE AN ISOLATED THUNDERSTORM OUT THERE. SUNDAY-SUNDAY NIGHT...RIDGING ALOFT SHOULD KEEP ANY THUNDER ACTIVITY LIMITED FOR THE REGION. MONDAY-MONDAY NIGHT...PATTERN STARTS BACK INTO THE SOUTHWEST FLOW ALOFT...SURFACE SOUTHEAST FLOW FOR CHANCE OF CONVECTION AGAIN. TEMPERATURES FAIRLY SEASONAL THROUGH THE WHOLE PERIOD. PROTON && .AVIATION... VFR. A SMALL CHANCE EXISTS THIS AFTERNOON SOUTH OF THE MISSOURI RIVER FOR SOME BRIEF THUNDER... OTHERWISE A GOOD FLYING DAY FOR NORTHEAST MONTANA EXPECTED. PROTON && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1057 PM MDT Sun Jun 9 2013 UPDATE TO AVIATION .DISCUSSION... Update forthcoming. Generally quiet and benign conditions expected overnight. The exception to this picture, as was the case last night, is weak short wave energy moving along the Canadian border and additional short wave energy over portions of southwest Montana. An isolated thunderstorm is possible over these areas. HRRR analysis suggests this activity should end by 07z. Temperatures look reasonable but have tweaked lows for Great Falls and Lewistown. Emanuel && .AVIATION... Updated 0457Z. VFR conditions will continue across north central/central/southwest Montana at least through Monday evening. Skies will remain mostly clear across the area into early Monday afternoon. However, light northerly upslope winds will keep an area of mid level cloudiness (around 5000 feet AGL) north and west of a line from KGTF to KHVR until 12Z or so. The airmass becomes weakly unstable again across southwest Montana after 21Z Monday as a disturbance approaches the area, for a chance of thunderstorms there, possibly impacting the KBZN terminal. Coulston && .PREV DISCUSSION...Issued 256 PM MDT Sun Jun 9 2013 Tonight through Tuesday...Generally quiet but breezy weather will continue this evening. However, once again this evening, there will be a slight chance of a shower or thunderstorm at opposite ends of the CWA: near the Canadian border and near Yellowstone Park. On Monday, an upper level wave will move through the Great Basin with flow aloft over the CWA backing around to the southwest by evening. The airmass also becomes unstable over far southwest Montana during the afternoon and evening with scattered thunderstorms developing over the mountains. This convection will move to the northeast into central Montana overnight and expand in coverage. There is also some indication that a mesoscale complex could form over central Montana during the overnight hours. Showers and thunderstorms become likely across much of the forecast area on Tuesday. From Tuesday evening through Wednesday afternoon there is some risk that a few thunderstorms may become strong to borderline severe with gusty winds being the main threat. mpj Tuesday night through Sunday...a rather unsettled weather pattern will reside over the region from much of the second half of the work week. A rather strong upper level disturbance is expected to develop over Central MT early Tue evening. Some of the storms could be on the strong side Tue evening. Thus pops have been raised for a good portion of North Central MT. Another round of storms will affect the region Wednesday into Thursday ahead the main cold front and upper level trof. Expect the precipitation to become a bit more widespread by Thursday over North Central MT. This heavier precip later in the week will slow down the rivers receding in Hill and Blaine counties. Colder air will move into the region by Thursday night...thus snow levels will be lowering into the 6500 to 7500 feet range. Expect some snow at higher elevations by Friday morning...but any snow accumulations should be minor. For Saturday...expect drier near seasonable temperatures to move back into the region. By next Sunday...a southwesterly flow develop aloft resulting in a chance for afternoon thunderstorms over Central and Southwest MT by late in the day. Brusda && .HYDROLOGY... Small streams and creeks remain high and out of their banks across a large portion of Central and North Central Montana. Areal flood warnings will continue for Hill/Blaine/Fergus Counties. Point flood warnings remain in effect for three locations: Big Sandy Creek near Havre, Clear Creek near Chinook, and the Milk River near Harlem. These points are expected to remain near or above flood stage into at least the early part of this week. The potential exists Tuesday for significant rain over areas currently under flood warnings. && .PRELIMINARY POINT TEMPS/POPS... GTF 47 74 48 72 / 0 0 30 40 CTB 41 71 44 70 / 10 10 10 40 HLN 49 79 50 77 / 0 10 30 40 BZN 45 81 47 77 / 10 20 30 50 WEY 42 78 41 71 / 20 30 30 40 DLN 48 82 49 76 / 0 30 40 50 HVR 46 74 49 72 / 10 0 20 50 LWT 46 72 48 69 / 0 0 40 70 && .TFX WATCHES/WARNINGS/ADVISORIES... Flood Warning through Monday morning for Blaine, Fergus, and Hill Counties. Flood Warning until further notice for Big Sandy Creek near Havre, Clear Creek near Chinook, and the Milk River near Harlem. && $$ weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
156 AM EDT MON JUN 10 2013 .SYNOPSIS... MOIST SOUTHERLY FLOW WILL CONTINUE AHEAD OF AN APPROACHING UPPER LOW PRESSURE TROUGH TONIGHT. THE TROUGH WILL PUSH A COLD FRONT INTO THE REGION MONDAY NIGHT...FOLLOWED BY HIGH PRESSURE TUESDAY AND WEDNESDAY. ANOTHER FRONT IS EXPECTED TO MOVE ACROSS THE AREA LATE IN THE WEEK. && .NEAR TERM /THROUGH TODAY/... AS OF EARLY MONDAY MORNING...KGSP RADAR SHOWS WIDESPREAD PRECIP LIFTING N TO NE ACROSS THE FCST AREA. CATEGORICAL POP LOOKS GOOD INITIALLY...BUT THERE IS A BACK END OF THE PRECIP LIFTING ACROSS THE SAVANNAH RIVER AS OF 05Z. THIS WILL ALLOW FOR A TEMPORARY LULL...AND POP WILL BE DECREASED THRU THE EARLY MORNING HOURS...BUT THIS COULD FILL IN AT ANY TIME. REMAINDER OF PREVIOUS DISCUSSION... THE UPPER TROUGH CONTINUES TO SHARPEN UP OVER THE MID MS RIVER VALLEY. ANTICIPATE IMPROVING AND SLIGHTLY BACKING FLOW ACROSS THE REGION TO ALLOW CONVECTION TO REGENERATE AND PERHAPS STRENGTHEN THROUGH THE OVERNIGHT HOURS. A LOW END SEVERE THREAT WILL LINGER GIVEN THE IMPROVING WIND SHEAR AND EASILY REACHABLE LCL HEIGHTS. GIVEN THE ROBUST 0 TO 3 KM BULK SHEAR VALUES NOW ADVERTISED ON THE LATEST RUC RUNS FOR THE OVERNIGHT...HAVE FEATURED AN ISOLD TORNADO MENTION IN THE HWO. CONDITIONS ON MONDAY WILL REMAIN FAVORABLE FOR HEAVY RAIN PRODUCING THUNDERSTORMS...WITH UNSTABLE SOUNDINGS ACROSS THE REGION AS THE UPPER TROUGH MOVES IN. A SFC COLD FRONT WILL ENTER THE MTNS FROM THE WEST AROUND MIDDAY. A DRY SLOT AHEAD OF THE FRONT WILL START TO DIMINISH POPS FROM WEST TO EAST. ONCE AGAIN...DEEP SHEAR CONTINUES TO INCREASE WITH THE ARRIVAL OF THE TROUGH...SO STORMS AHEAD OF THE FRONT MAY BE QUITE VIGOROUS...ESPECIALLY IN ERN SECTIONS. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY/... AS OF 1245 PM SUNDAY...LINGERING DEEP CONVECTIVE CHANCES WILL REMAIN IN THE FORECAST THRU MONDAY NIGHT SINCE THE 09/12 UTC OP SHORT RANGE MODELS CONTINUE TO ADVERTISE THE PASSAGE OF A SHARP LOOKING S/WV TROUGH. WITH THE LATEST NAM RUN NOW IN STEP WITH THE OP GFS IN TRANSLATING UPPER TROUGH AXIS DOWNSTREAM OF THE CWFA BY TUESDAY AFTERNOON...WITH PLAN ON SHAVING BACK POP A BIT MORE...ESPECIALLY GIVING THE PALTRY MOS POPS...FALLING SFC DWPTS AND SOME DOWNSLOPE FLOW. MAX TEMPERATURES REMAIN SLATED TO REBOUND TO VALUES VERY CLOSE TO CLIMO. THE CWFA WILL BE UNDER BROADLY DIFFLUENT WNW FLOW ALOFT TUESDAY NIGHT INTO WEDNESDAY AND IT IS WITHIN THE REALM OF POSSIBILITY THAT OHIO VALLEY MCS ACTIVITY WILL MAKE A RUN AT THE NW CWFA BY WED AM...BUT CONFIDENCE IS STILL NOT HIGH ENUF TO INTRODUCE ANYTHING AT THIS POINT. UNLESS IT BECOMES OBVIOUS THAT AN IMPULSE/OUTFLOW IS GOING TO MAKE IT/S WAY ACRS THE CWFA WEDNESDAY WILL PLAN ON LIMITING DIURNAL TSTM CHANCES TO THE MTNS/LEE TROUGH LOCALES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 1130 AM EDT SUNDAY...A BROAD UPPER RIDGE OF H5 HIGH WILL REMAIN ANCHORED ACROSS THE SOUTHERN PLAINS...LEAVING OUR FORECAST AREA UNDER N/NW FLOW ALOFT THROUGH MUCH OF THE MEDIUM RANGE PERIOD. AT THE SURFACE...A WEAK SURFACE HIGH PRESSURE WILL PREVAIL WED NIGHT INTO THURSDAY ACROSS THE REGION PROVIDING MOSTLY DRY CONDITIONS. A COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION THU NIGHT INTO EARLY FRI. MODELS AGREE THAT THE FRONT WILL WEAKEN AS IT CROSSES THE CWA. HENCE...I HAVE CARRIED LOW END CHANCE POPS DURING THIS PERIOD. CONDITIONS LOOK DRY FOR THE NEXT WEEKEND WITH HIGH PRESSURE BUILDING ACROSS THE REGION. TEMPS ON THURSDAY WILL BE AROUND 3-5 DEGREES ABOVE NORMAL WITH HIGHS REACHING THE LOW 90S EAST OF THE MTNS. THEN TEMPS BACK TO NEAR...OR A FEW DEGREES BELOW NORMAL FRI/SAT BEFORE WARMING UP TO NEAR NORMAL SUN. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AT KCLT AND ELSEWHERE...WIDESPREAD CONVECTION LIFTING N AND NE ACROSS THE REGION AS OF 06Z...WHICH WILL REQUIRE SOME HANDLING OF LOWER VISIBILITY IN TEMPO GROUPS. OTHERWISE...A TREND CONTINUES WITH CLOUD CEILING DROPPING INTO THE IFR CATEGORY AND THINK THAT WILL PREVAIL FOR MOST OF THE PRE-DAWN HOURS AT ALL TAF SITES...WITH OCCASIONAL MVFR HOLES THAT WILL NOT BE HANDLED IN A TEMPO AT MOST SITES. KAVL MIGHT BE THE LAST TO GO COMPLETELY IFR BUT IT SHOULD HAPPEN BEFORE SUNRISE. THERE COULD BE A LULL IN PRECIP ACROSS THE REGION AROUND DAYBREAK BUT THERE IS A LINE OF CONVECTION OVER THE TN VALLEY THAT MAY ARRIVE AFTER SUNSET. THERE IS SOME INDICATION IN THE MODEL GUIDANCE THAT A LINE OF THUNDERSTORMS WILL MOVE SLOWLY EAST ACROSS THE REGION DURING THE DAYLIGHT HOURS. SO...AFTER SUNRISE THE IFR CEILING LIFTS UP TO MVFR AT ALL SITES...BUT THEN A 4 HR TEMPO FOR THUNDERSTORMS WAS INCLUDED FROM WEST TO EAST BASED ON THE TIMING OF THE 4KM WRF...WHICH SEEMS REASONABLE. AFTER THAT LINE OF STORMS MOVES THROUGH...BY LATE AFTERNOON AT KCLT...EXPECT ANOTHER LULL. THERE COULD BE MORE CONVECTION LATER IN THE EVENING BUT THAT DETAIL HAD TO BE LEFT OUT OF THE TAFS AT THIS POINT. WIND WILL GENERALLY BE S TO SW THROUGH THE PERIOD. OUTLOOK...A COLD FRONT WILL CROSS THE REGION MONDAY NIGHT WITH CONTINUED SHOWERS AND STORMS...ESPECIALLY IN ERN SECTIONS. CONDITIONS WILL IMPROVE ON TUE IN THE MIDWEEK AS UPPER LEVEL HIGH PRESSURE BUILDS IN. THUNDERSTORMS COULD ARRIVE FROM THE NORTHWEST LATE WED AND AGAIN ON THU. CONFIDENCE TABLE... 06-12Z 12-18Z 18-24Z 00-06Z KCLT LOW 59% HIGH 81% MED 76% HIGH 83% KGSP MED 63% HIGH 91% HIGH 80% HIGH 95% KAVL HIGH 92% HIGH 82% HIGH 80% MED 75% KHKY MED 76% HIGH 89% MED 73% HIGH 83% KGMU HIGH 87% HIGH 93% HIGH 91% HIGH 95% KAND HIGH 87% HIGH 83% HIGH 93% 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...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR GAZ010-017-018- 026-028-029. NC...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR NCZ033-035>037- 048>053-056>059-062>065-068>072-082-501>510. SC...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR SCZ001>014-019. && $$ SYNOPSIS...JOH NEAR TERM...HG/PM/WIMBERLEY SHORT TERM...CSH LONG TERM...JOH AVIATION...PM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
348 AM CDT MON JUN 10 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 346 AM CDT MON JUN 10 2013 CLEAR SKIES/LIGHT WINDS AND RESIDUAL BOUNDARY LAYER MOISTURE FROM RECENT RAINS ALLOWING DENSE FOG TO DEVELOP IN WESTERN/CENTRAL PARTS OF THE CWA EARLY THIS MORNING. HRRR HAS LATCHED ONTO EXPANSION OF THE LOWEST VISIBILITIES WHICH HAS OCCURRED OVER THE PAST HOUR OR SO...AND IT SHOWS POTENTIAL FOR DENSE FOG PERSISTING IN THE SURFACE RIDGE AXIS THROUGH ABOUT 13-14Z WITH RAPID IMPROVEMENT THEREAFTER. ISSUED DENSE FOG ADVISORY DUE TO EXPECTED PERSISTENCE...THOUGH MAY STILL BE A BIT PATCHY IN SPOTS...ESPECIALLY THE FAR WEST WHERE THE WIND MAY PICK UP A BIT AS THE RIDGE SHIFTS EAST. STRATUS AND A BIT MORE WIND EAST OF THE RIDGE AXIS HAS HELPED TO HOLD VISIBILITY UP ACROSS NORTHWEST IOWA AND PARTS OF SOUTHWEST MN THUS FAR...SO DID NOT INCLUDE THEM IN THE ADVISORY AT THIS TIME...THOUGH WILL WATCH FOR DOWNWARD TREND SHOULD THE STRATUS CLEAR. SEEING SOME ACCAS STREAMING TOWARD FAR WESTERN COUNTIES EARLY THIS MORNING AS WELL. SOUTHERN EDGE HAS SHOWN TENDENCY TO DISSIPATE AS IT SHIFTS EAST... AND 06Z NAM INDICATES THIS TREND AS WELL...KEEPING BULK OF HIGHER MID LEVEL MOISTURE NORTH OF OUR CWA THROUGH THE MORNING. DID BRING IN A LITTLE HIGHER SKY COVER TO OUR NORTHWEST EARLY...BUT THINK MOST OF THE DAY SHOULD SEE FAIR AMOUNT OF SUNSHINE. THUS AFTER THE FOG BURNS OFF...EXPECT TEMPERATURES TO REBOUND NICELY...THOUGH PERHAPS A BIT MORE SLOWLY IN THE EAST WHERE STRATUS MAY LINGER INTO THE MID TO LATER MORNING HOURS. WITH 925MB TEMPERATURES FORECAST TO RISE INTO THE 20S C BY 11/00Z...HIGHS FROM THE UPPER 70S EAST TO THE MID-UPPER 80S SOUTHWEST LOOK GOOD. MID LEVEL CLOUDS WILL BE ON THE INCREASE MONDAY NIGHT AS ATMOSPHERE ABOVE 600 MB SATURATE IN RESPONSE TO INCREASE IN THETAE ADVECTION. WHILE SHORTWAVE IS EXPECTED TO MOVE ACROSS THE FORECAST AREA...APPEARS AS THOUGH ATMOSPHERE WILL REMAIN EFFECTIVELY CAPPED LIMITING THUNDERSTORM POTENTIAL TO FAR WESTERN PORTIONS OF CWA IN CENTRAL SOUTH DAKOTA. THE OUTSIDE CHANCE OF AN ELEVATED STORMS WILL CONTINUE THROUGH TUESDAY MORNING...BUT EXPECT CHANCES TO DWINDLE THROUGHOUT THE DAY ON TUESDAY. FORECAST AREA REMAINS IN EASTERLY FLOW THROUGHOUT THE DAY ON TUESDAY AS WARM FRONT LIFTS NORTH TOWARDS THE CWA. TOUGH CALL ON CONVECTION CHANCES TUESDAY NIGHT WITH STRONG MID LEVEL CAP PRESENT. MODELS HIND THAT CAP MAY TRY TO WEAKEN...AND THE BEST CHANCE FOR THUNDERSTORMS REMAINS ACROSS THE NORTHERN FRINGE OF THE FORECAST AREA. IF STORMS ARE ABLE TO DEVELOP...THEY WOULD LIKELY QUICKLY BECOME SEVERE PRODUCING SEVERE HAIL WITH STRONG MID LEVEL LAPSE RATES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM CDT MON JUN 10 2013 HAVE LEFT LINGERING POPS INTO WEDNESDAY...THOUGH THERE IS REALLY A LACK OF ANY LARGE SCALE FOCUSING MECHANISM WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NORTH. AS SUCH...JUST HAVE A GENERAL 20-40 CHANCE WHICH WILL BE VERY DEPENDENT ON WHAT HAPPENS TUESDAY NIGHT. THURSDAY INTO THE BETTER PORTION OF FRIDAY SHOULD BE RELATIVELY DRY. THE EXCEPTION TO THIS WOULD BE LATE ON THURSDAY NIGHT AS WARM AIR ADVECTION INCREASES UNDER SOUTHERLY FLOW AND COULD SEE ACCAS SHOWERS. POTENTIAL FOR DEEP CONVECTION FRIDAY NIGHT CONTINUES TO INCREASE AS UPPER LEVEL LOW PRESSURE SYSTEM LIFTS NORTHEAST INTO CENTRAL CANADA AND TRAILING COLD FRONT MOVES ACROSS THE FORECAST AREA. WHAT CONTINUES TO BE IMPRESSIVE ABOUT THIS SET UP ARE THE VERY STEEP LAPSE RATE FROM 700-400 MB AND SPEED SHEAR ALOFT INDICATING THE POTENTIAL FOR VERY LARGE HAIL IF THUNDERSTORMS ARE ABLE TO DEVELOP. THE UNSETTLED PATTERN CONTINUES INTO THE WEEKEND AS UPPER LEVEL LOW RE-ESTABLISHES ITSELF OFF THE PACIFIC NW COAST. PIECES OF ENERGY PERIODICALLY BREAK OFF THE UPPER LEVEL LOW EJECTING INTO THE PLAINS. AT THIS POINT...IT CONTINUES TO BE DIFFICULT TO PINPOINT PRECISE TIMING OF DEEP CONVECTION...BUT HAVE STARTED TO TWEAK DAYTIME POPS DOWN AND NOCTURNAL POPS UP TO HELP ACCOUNT FOR TYPICAL DIURNAL PATTERN THIS TIME OF YEAR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1048 PM CDT SUN JUN 9 2013 FOR THE 06Z TAFS...CONFIDENCE IS NOT REAL HIGH THROUGH SUNRISE MONDAY. WITH DECREASING WINDS AND CLOUDS...AM STILL CONCERNED ABOUT RADIATIONAL FOG DEVELOPING THROUGH THE AREA. RADIATIONAL FOG IS DIFFICULT TO FORECAST FOR ANY PARTICULAR SPOT LOCATION. THAT SAID...IT IS DISTURBING THAT SOME CEILINGS HAVE GONE UNDER 1000 FEET EAST OF I 29...AND IN SOUTHWEST MN...VISIBILITIES ARE ALREADY RANGING ANYWHERE FROM A 1/2 MILE AT SLAYTON TO 10 MILES. THEREFORE WITH THE MOIST GROUND AND VERY SMALL SURFACE DEW POINT DEPRESSIONS... AREAS OF FOG IS A LIKELY SCENARIO LATE TONIGHT AND EARLY MONDAY. FOR NOW...KEPT TEMPO IFR CONDITIONS FOR THE THREE TAF SITES AROUND THE SUNRISE HOURS. BUT IT MUST BE NOTED THAT CONDITIONS COULD GET WORSE THAN THIS AT LEAST FOR A BRIEF PERIOD OF TIME. UNFORTUNATELY THAT BRIEF PERIOD OF TIME WOULD LIKELY COINCIDE WITH EARLY MORNING FLIGHTS. SO THIS WILL NEED WATCHED VERY CLOSELY AND ALSO HEDGED WITH A SCT003 DECK AT KFSD AND KSUX AS A HEADS UP. OTHERWISE TOWARD MID MORNING...IT WILL BE VFR AS ANY FOG FORMATION SHOULD BE FAIRLY SHALLOW IN DEPTH...AT LEAST ALONG AND WEST OF I 29. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR SDZ038>040- 053>056-059>062-065>071. MN...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR MNZ071-072- 080-097-098. IA...NONE. NE...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ013-014. && $$ SHORT TERM...JH LONG TERM... AVIATION...MJ
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1123 PM CDT SUN JUN 9 2013 .UPDATE...FOR 06Z AVIATION FORECAST && .AVIATION... BAND OF CONVECTION HAS SLOWED TO A CRAWL FROM EARLIER PROJECTIONS AND CONTINUES TO WEAKEN WHILE DIMINISHING IN COVERAGE. LOW CONFIDENCE IN TERMINAL FORECASTS ESPECIALLY FIRST 12 HOURS. CLARKSVILLE STILL IN THE RAIN AND WILL BE FOR A COUPLE MORE HOURS. NASHVILLE YET TO GET RAIN BUT WILL SHORTLY. HAVE INCLUDED THUNDER FROM 06Z TO 08Z THEN VICINITY SHOWER THROUGH THE OVERNIGHT. HAVE VICINITY SHOWERS AT CROSSVILLE BECOMING PREDOMINATE AROUND 09Z AND CONTINUE THROUGH 14Z. COLD UPPER LOW WILL DROP DOWN INTO THE OHIO VALLEY ON MONDAY WITH INCREASED INSTABILITY IN THE AFTERNOON ACROSS MY CWA SO HAVE INCLUDED VICINITY THUNDERSTORMS AT ALL TERMINALS AFTER 18Z MONDAY. BOYD && .PREV DISCUSSION... /ISSUED 919 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... CONVECTIVE LINE CONTINUING TO HOLD TOGETHER BUT OVERALL WEAKENING HAS OCCURRED DURING THE LAST HOUR. THE ESTIMATED TIME OF ARRIVAL IN DOWNTOWN NASHVILLE IS 1020 PM CDT. BOYD PREV DISCUSSION... /ISSUED 857 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE SEGMENT MOVING INTO MONTGOMERY COUNTY REMAINS STRONG OTHERWISE LINE OF CONVECTION OVERALL HAS WEAKENED. EXPECT THIS TREND TO CONTINUE. RAINFALL IN SOUTHWEST BENTON COUNTY TOTALED 1.75 INCHES. FLASH FLOOD GUIDANCE IS JUST ABOVE 2 INCHES FOR THE AREA. THE HEAVIER RAINS HAVE NOW PULLED EAST. BOYD PREV DISCUSSION... /ISSUED 814 PM CDT SUN JUN 9 2013/ UPDATE... HAVE UPDATED GRIDS AND ZONES TO REFLECT BETTER THE APPROACHING SHOWERS AND STORMS NOW CROSSING THE TENNESSEE RIVER. ALTHOUGH A STORM OR TWO COULD BE STRONG TO SEVERE STILL THINK ACTIVITY WILL GENERALLY WEAKEN AS IT MOVES FARTHER EAST INTO MIDDLE TENNESSEE THIS EVENING...WITH LOSS OF HEATING AND UPPER SUPPORT. STATIONARY FRONT FROM WESTERN TENNESSEE DOWN INTO LOUISIANA WITH CONVECTION ALL ALONG THIS BOUNDARY. CLOUDS TOPS HAVE BECOME COLDER LAST COUPLE OF HOURS ALONG THE BOUNDARY WITH SURFACE DEWPOINTS AROUND 70 DEGREES. BOUNDARY MAY WORK INTO WESTERN MIDDLE TENNESSEE OVERNIGHT AND WITH TRAINING OF ECHOES WE COULD BE LOOKING AT LOCALLY HEAVY RAINFALL. BOYD PREV DISCUSSION... /ISSUED 752 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF CONVECTION NEARING TENNESSEE RIVER AT 0030Z HAS PULLED AHEAD OF COLDER AIR ALOFT AND ALONG WITH LOSS OF HEATING EXPECT CONVECTION TO CONTINUE TO WEAKEN AS IT ADVANCES EASTWARD INTO WESTERN MIDDLE TENNESSEE OVER THE NEXT 1 TO 2 HOURS BUT THERE STILL COULD BE A STRONG STORM OR TWO. HAVE SOME CONCERN FOR STATIONARY FRONT THAT EXTENDS FROM WEST TENNESSEE DOWN INTO LOUISIANA AND A WAVE THAT HAS JUST DEVELOPED ON THE FRONT IN LOUISIANA. SURFACE DEWPOINTS AROUND 70 EXTENDS ALL ALONG THIS BOUNDARY. WILL HAVE TO WATCH FOR CONVECTION TRAINING NORTHEAST OVERNIGHT. BOYD PREV DISCUSSION... /ISSUED 704 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... LINE OF STRONG CONVECTION CURRENTLY MOVING EASTWARD THROUGH WEST TENNESSEE AND WAS 40 MILES WEST OF THE TENNESSEE RIVER AT 00Z. AM EXPECTING THIS ACTIVITY TO WEAKEN AS IT CROSSES THE TENNESSEE RIVER. BOYD PREV DISCUSSION... /ISSUED 641 PM CDT SUN JUN 9 2013/ UPDATE...FOR 00Z AVIATION FORECAST AVIATION...EXPECT STORM STRENGTH TO DIMINISH AFTER SUNSET BUT SCATTERED CONVECTION WILL LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS ACROSS MIDDLE TENNESSEE. SLUGGISH UPPER TROUGH CENTERED OVER MIDDLE MISSISSIPPI VALLEY AT LATE AFTERNOON WILL MOVE DOWN INTO EASTERN ILLINOIS BY 12Z MONDAY. EXPECT SOME SCATTERED CONVECTION DURING THE DAY ON MONDAY AS UPPER TROUGH AXIS WITH COLDER TEMPS SWINGS ACROSS THE TENNESSEE VALLEY. MESOSCALE...STORM CELL MOVING INTO SOUTHWEST SUMNER MAY BE MORE OF A RED HERRING BUT DOES HAVE A SUPERCELLULAR APPEARANCE (ITS GOT THE LOOK). INBOUND WINDS WERE ON THE ORDER OF 35 KNOTS AT 2326Z. STORM HAS TURNED RIGHT LAST 20 MINUTES TAPPING ENVIORNMENTAL WINDS AND MORE HELICITY. BOYD PREV DISCUSSION... /ISSUED 446 PM CDT SUN JUN 9 2013/ MESOSCALE UPDATE... 500 MBAR COLD TEMP AXIS RUNNING DOWN THROUGH EASTERN MISSOURI AND DOWN THROUGH EASTERN ARKANSAS JUST WEST OF MISSISSIPPI RIVER AT 21Z. THIS AXIS OF COLDER TEMPS WILL BEGIN SWEEPING INTO THE WESTERN AREAS OF CURRENT WW SHORTLY WHICH WILL ENHANCE ACTIVITY IN THOSE AREAS FOR NEXT FEW HOURS. LATEST SREF RUN WEAKENS INSTABILITY IN MIDDLE TENNESSEE RATHER QUICKLY AFTER SUNDOWN. THIS ALSO BROUGHT OUT BY H-TRIPLE-R HIGH RESOLUTION MODEL. THINK BEST SCENARIO AT THIS TIME WOULD BE FOR LINE OF STRONG TO POSSIBLE SEVERE CONVECTION TO DEVELOP ALONG MISSISSIPPI RIVER BY 00Z AND MOVE EASTWARD INTO WESTERN TENNESSEE AND BEGIN WEAKENING BY 03Z AS IT APPROACHES THE TENNESSEE RIVER AND CONTINUE WEAKENING AS IT MOVES INTO MIDDLE TENNESSEE FROM 03Z AND 06Z. BOYD PREV DISCUSSION... /ISSUED 307 PM CDT SUN JUN 9 2013/ HE BULK OF THE CONVECTION THIS AFTERNOON HAS SHIFTED ACROSS EASTERN MIDDLE TN AS THE UPPER DISTURBANCE CONTINUES TO PULL OFF TO THE EAST. LATEST LAPS INSTABILITY PARAMETERS IS SHOWING AN INCREASE IN INSTABILITY ACROSS WESTERN AREAS. SFC AND UPPER LEVEL TROUGH AXIS IS STACKED NICELY AND EXTENDS SOUTHWARD FROM IOWA. THESE 2 FEATURES WILL REMAIN IN PHASE AND WILL TRACK EASTWARD ACROSS THE MID STATE OVERNIGHT. SHOULD SEE ISOL TO SCATTERED CONVECTION REDEVELOP LATE THIS AFTERNOON AND EVENING ACROSS WESTERN MIDDLE TN AND A FEW STORMS COULD REACH STRONG LEVELS. THEN...LATER TONIGHT...A LINE OF THUNDERSTORMS WILL MOVE THROUGH THE MID STATE...A FEW STORMS COULD AGAIN REACH STRONG LEVELS WITH HIGH WINDS AND SOME SMALL HAIL. TIMING OF THE LINE APPEARS TO BE AROUND 8PM TO 2AM ACROSS WESTERN MIDDLE TN AND 11PM TO 5AM ACROSS EASTERN AREAS. LATEST HRRR DATA APPEARS TO WANT TO WEAKEN THE SYSTEM BY THE TIME IT REACHES INTO EASTERN MIDDLE TN. ON MONDAY...NAM MODEL WILL BE TOSSED AS GRAPHICS DEPICT NEAR 70 DEW POINTS AT 18Z...AND THIS IN TURN HAS EVOKED OVERLY AGGRESSIVE CONVECTIVE FEEDBACK. NUMERICAL MET DATA SHOWS DRIER AIR MIXING DOWN TO THE SFC WITH DEWS IN THE LOWER 60S. GFS AND MAV DATA SHOWS EVEN LOWER DEWPOINTS. NEVERTHELESS...WE WILL DESTABILIZE BY LATE AFTERNOON WITH MID AND UPPER LEVEL CAPES REINFORCED WITH THE UPPER TROUGHING PATTERN. COULD SEE ISOL TO SCT STRONG TO SVR CONVECTION...WIND AND HAIL. MONDAY NIGHT...DRIER AIR TO WORK IN AS THE UPPER TROUGH PULLS EASTWARD. POPS WILL THEREFORE SHUTDOWN WITH DRY WEATHER THROUGH WEDNESDAY. A DEFINITIVE WARMING TREND WILL BE AT HAND AS UPPER HIGH STRENGTHENS OVER TX AND OUR HEIGHTS RISE. IN THE EXT FCST...WEAK NORTHWEST FLOW WILL SET THE STAGE FOR POTENTIAL MCS IMPACTS...THE FIRST OF WHICH WILL BE ON THURSDAY. THEN ANOTHER POTENTIAL MCS FOR SAT OR SUN. OTHERWISE...WARM CONDITIONS WITH HIGHS GENERALLY IN THE LOWER 90S WEST OF PLATEAU. VERSUS THE MEX GUIDANCE...AGAIN...THE MEX APPEARS TO BE TOO AGGRESSIVE WITH THAT 97 AT BNA FOR WED. WILL CONTINUE TO UNDERCUT AND GO 94. A GENERAL UNDERCUT WILL BE UTILIZED THROUGHOUT THE EXTENDED. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 01
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1141 PM CDT SUN JUN 9 2013 .DISCUSSION... SEE 06Z AVIATION DISCUSSION. && .AVIATION... WET GROUND AND CLEARING SKIES SHOULD ALLOW SOME PATCHY FOG TO DEVELOP OVER RURAL TAF SITES TONIGHT. ANY MVFR VSBY/CIGS WILL MIX OUT EARLY MONDAY MORNING. GFS CONTS TO BE MORE AGGRESSIVE WITH RAIN CHANCES ON MONDAY DUE TO AN INVERTED UPPER LEVEL TROUGH OVER DEEP SOUTH TEXAS. FCST SOUNDINGS DON`T SHOW MUCH IN THE WAY OF A CAP AND WITH PW VALUES NEAR 1.70 INCHES AND CONVECTIVE TEMPS IN THE UPPER 80S...FEEL SHRA/TSRA WILL BE POSSIBLE OVER MAINLY THE SOUTHERN TAF SITES...OR KIAH SOUTHWARD. CONDS IMPROVE RAPIDLY BY 11/00Z WITH VFR CONDS EXPECTED MONDAY NIGHT. 43 && .PREV DISCUSSION... /ISSUED 849 PM CDT SUN JUN 9 2013/ DISCUSSION... THIS EVENINGS SOUNDINGS HAVE PRECIPITABLE WATER VALUES OF 1.87 AND 1.56 INCHES. THE ATMOSPHERE IS MORE STABLE THAN IT WAS 24 HOURS AGO...BUT ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE STILL POSSIBLE OVER THE EASTERN PORTIONS OF SOUTHEAST TEXAS TOMORROW AFTERNOON. THE AXIS OF THE UPPER LEVEL TROUGH SHOULD BE JUST OFF THE COAST. WITH SUBSIDENCE OVER THE AREA AND CONVERGENCE AT 200-300 MB. THE COVERAGE SHOULD BE SPOTTIER THAN IT WAS TODAY. OVERALL...THE PREVIOUS FORECAST LOOKS TO BE ON TRACK. NO CHANGES ARE NECESSARY AT THIS TIME. 44 PREV DISCUSSION... /ISSUED 622 PM CDT SUN JUN 9 2013/ DISCUSSION... SEE 00Z AVIATION DISCUSSION. AVIATION... CONDITIONS HAVE STABILIZED ACROSS SE TX AND AM EXPECTING THE CIRRUS SHIELD TO DISSIPATE IN THE NEXT HOUR OR SO. CONVECTION SHOULD REMAIN TO THE EAST AND TO THE WEST OF SE TX. AM A LITTLE CONCERNED ABOUT PATCHY FOG IN RURAL AREAS OVERNIGHT WITH GROUNDS REMAINING WET AND LIGHT WINDS. FCST SOUNDINGS ON MONDAY KINDA CAUGHT ME BY SURPRISE. 18Z SOUNDINGS SHOW A BREAKABLE CAP AND CONVECTIVE TEMPS IN THE UPPER 80S. THE GFS IN PARTICULAR IS AGGRESSIVE WITH RAIN CHANCES AND GETS SOME SUPPORT FROM THE HI-RES ARW. THE LATEST RAP SHOWS A WEAK TROUGH AXIS ACROSS SE TX AT 16Z SO FEEL SOME PCPN SHOULD DEVELOP WITH FURTHER HEATING. ADDED VCSH FOR MON AFTN AND WILL WAIT FOR 00Z RUNS BEFORE EITHER ADDING THUNDER OR REMOVING PCPN ALL TOGETHER. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 72 94 74 95 74 / 20 10 10 10 10 HOUSTON (IAH) 73 93 75 94 75 / 20 20 10 10 10 GALVESTON (GLS) 81 87 80 88 80 / 30 20 10 20 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...44 AVIATION/MARINE...43
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 424 AM CDT MON JUN 10 2013 WV IMAGERY AND RAP ANALYSIS SHOWED AN UPPER LOW WEAKENING AS IT MOVED ESE INTO CENTRAL IL. SCATTERED SHOWERS ASSOCIATED WITH ITS DEFORMATION ZONE WERE ATTEMPTING TO WRAP BACK INTO OUR FAR SE COUNTIES...BUT WERE DISSIPATING. STRONG ZONAL FLOW ALOFT WAS IN PLACE FROM THE PACIFIC NW THROUGH MINNESOTA...WITH A WELL-DEFINED S/W TROF AND 110 KT JET STREAK MOVG ALONG THE NORTH DAKOTA/CANADIAN BORDER. THIS ENERGY APPEARED POISED TO CLIP NORTHERN WI LATER TODAY. CLOUDS HAD SCATTERED OUT OVER MUCH OF GRB EARLY THIS MORNING...AND PATCHY FOG WAS DEVELOPING. PATCHY FOG SHOULD DISSIPATE QUICKLY BY MID-MORNING. SHOWERS ASSOCIATED WITH THE DEPARTING UPPER SYSTEM ARE NOT EXPECTED TO MAKE IT INTO OUR FAR SE COUNTIES EARLY TODAY...SO WILL NOT MENTION. S/W TROF AND JET STREAK MOVG RAPIDLY THROUGH ND AND NW MN SHOULD MOVE INTO N WI LATE THIS MORNING AND AFTERNOON...AND COMBINE WITH DAYTIME HEATING AND WEAK LOW-LEVEL CONVERGENCE TO PRODUCE SCT SHOWERS OVER MUCH OF THE FA. THE SHOWERS ARE EXPECTED TO MOST NUMEROUS OVER NC/FAR NE WI...WHERE FORCING AND INSTABILITY (CAPE 300-400 J/KG) IS EXPECTED TO BE GREATEST. HAVE INCLUDED A MENTION OF ISOLD TSTMS OVER THE FAR NORTH. CONSIDERED GOING WITH LIKELY POPS OVER NORTHERN WI...BUT OPTED FOR HIGH CHANCE POPS INSTEAD...AS THE 00Z ECMWF CAME IN WITH MUCH LESS QPF THAN ITS PREVIOUS RUN. MIXING THROUGH 875-850 MB SUPPORTS HIGH TEMPS IN THE MIDDLE 70S AWAY FROM LAKE MICHIGAN. GENERALLY DRY CONDITIONS ARE EXPECTED ACROSS THE REGION TONIGHT... WITH LIGHT WINDS AND PARTLY CLOUDY SKIES LEADING TO SOME FOG DEVELOPMENT OVERNIGHT. EXPECT A MILD NIGHT...WITH MIN TEMPS IN THE 50S. ON TUESDAY...ADDITIONAL SHORT-WAVE AND JET ENERGY WILL SKIM BY TO OUR NORTH AS A WEAK/SHALLOW COLD FRONT DROPS INTO THE REGION. HAVE CONTINUED WITH LOW POPS OVER NORTHERN WI...BUT POPS MAY NEED TO BE EXPANDED OVER MORE OF THE FORECAST AREA WITH SUBSEQUENT FCSTS. MIXING THROUGH 850-800 MB SUPPORTS A WARM DAY...WITH HIGHS IN THE LOWER 80S. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 424 AM CDT MON JUN 10 2013 MODEL GUIDANCE CONTINUED TO FOCUS ON A MORE SOUTHERLY SOLUTION FOR AN APPROACHING SHORT WAVE...SURFACE LOW PRESSURE SYSTEM AND ASSOCIATED FRONTAL BOUNDARY FOR TUESDAY NIGHT AND WEDNESDAY. HAVE GONE WITH A CHANCE OF SHOWERS AND THUNDERSTORMS FOR PARTS OF CENTRAL AND EAST CENTRAL WISCONSIN AND LEFT THE NORTH DRY BECAUSE OF THIS. SURFACE HIGH PRESSURE AND AN UPPER LEVEL RIDGE ACROSS THE CENTRAL CONUS SHOULD KEEP THURSDAY AND FRIDAY DRY...BEFORE THE NEXT SHORT WAVE AND AN APPROACHING COLD FRONT BRING A CHANCE OF SHOWERS AND THUNDERSTORMS BACK TO THE AREA FOR FRIDAY NIGHT AND SATURDAY. PRECIPITATION MAY LINGER INTO SUNDAY SO HAVE LEFT SOME CHANCE POPS IN FOR SATURDAY NIGHT AND SUNDAY AS WELL. TEMPERATURES SHOULD BE WITHIN A FEW DEGREES OF NORMAL FOR MOST OF THE FORECAST PERIOD. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1150 PM CDT SUN JUN 9 2013 LOW PRESSURE WILL CONTINUE TO DRIFT ACROSS NORTHERN ILLINOIS OVERNIGHT WITH SCATTERED SHOWERS ACROSS CENTRAL WISCONSIN CONTINUING TO WANE. VFR CIGS WILL GRADUALLY DETERIORATE TO MVFR FROM WEST TO EAST TOWARD DAYBREAK WITH SOME PATCHY FOG POSSIBLE ESPECIALLY ACROSS CENTRAL WISCONSIN. SCATTERED SHOWERS ASSOCIATED WITH SURFACE TROUGH WILL INCREASE IN COVERAGE ESPECIALLY ACROSS THE NORTHEAST HALF OF THE FORECAST AREA BY LATE MORNING AND WILL PERSIST INTO THE AFTERNOON UNTIL SURFACE TROUGH MOVES EAST OF THE FORECAST AREA TOWARD EARLY EVENING. VFR CONDITIONS WILL RETURN EARLY MONDAY EVENING AS WEAK HIGH PRESSURE MOVES INTO THE REGION. SOME PATCHY FOG IS ALSO POSSIBLE TOWARD MIDNIGHT TUESDAY WITH LIGHT WINDS...CLEARING SKIES AND RESIDUAL BOUNDARY LAYER MOISTURE PERSISTING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....KIECKBUSCH LONG TERM......MG AVIATION.......ESB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
728 AM EDT MON JUN 10 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 412 AM EDT MON JUN 10 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG EXTENDING FM NW ONTARIO THRU THE GREAT LKS TO THE MID ATLANTIC COAST. THERE ARE 2 CLOSED LOWS UPSTREAM...ONE MOVING THRU THE MID MS RIVER VALLEY AND ANOTHER OVER SASKATCHEWAN TO THE N OF MEAN RDG OVER THE WRN CONUS. A SHRTWV IS MOVING INTO NE MN BTWN THE 2 CLOSED LOWS AND GENERATING AN AREA RA OVER FAR NW LK SUP AND NE MN AS THE DPVA/ DEEP LYR QVECTOR CNVGC AHEAD OF THIS FEATURE INTERACTS WITH DEEP MSTR SHOWN ON THE 00Z INL RAOB. BUT SINCE THE DEEPER MSTR AND FORCING ASSOCIATED WITH THE CLOSED LO IN THE MID MS RIVER VALLEY ARE TO THE S OF UPR MI...THERE IS NO DYNAMIC SUPPORT FOR PCPN OVER UPR MI...WITH AN ABSENCE OF SGNFT RADAR RETURNS OVER THE AREA DESPITE MOCLDY SKIES. THE CLDS HAVE LIMITED THE DIURNAL FALL OF TEMP...WITH MOST PLACES REPORTING TEMPS IN THE 50S TO LO 60S EARLY THIS MRNG. SOME BREAKS IN THE CLDS ARE MOVING NE INTO UPR MI FM WI. THICKER CLDS/SOME ISOLD -SHRA ARE MOVING N THRU LWR MI. MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS ASSOCIATED WITH SHRTWV NOW MOVING THRU NE MN. TDAY...SHRTWV IN NE MN IS PROGGED TO LIFT NEWD INTO NW ONTARIO ON THE SE FLANK OF NEARLY STNRY CLOSED LO OVER SASKATCHEWAN. DPVA/H85-5 QVECTOR CNVGC ASSOCIATED WITH THIS FEATURE ARE PROGGED TO BRUSH THE NW CWA INTO THIS AFTN BEFORE THE SHRTWV LIFTS FARTHER TO THE NE AND GIVES WAY TO DNVA/DEEP LYR QVECTOR DVGC/MID LVL DRYING. MODELS SHOW BULK OF PCPN ACCOMPANYING THIS SHRTWV PASSAGE REMAINING TO THE NW OF EVEN THE KEWEENAW. SO OPTED TO CUT POPS TO NO HIER THAN SCHC THIS MRNG OVER THE LAND CWA. DID ADD SCHC POPS OVER THE E TO ACCOUNT FOR ISOLD -SHRA MOVING N THRU NRN LWR MI. EVEN AFT THE DYNAMIC SUPPORT SWINGS TO THE N THIS AFTN...BULK OF RECENT NUMERICAL GUIDANCE IS GENERATING QPF OVER MAINLY THE INTERIOR W HALF OF THE CWA AS DAYTIME HEATING DESTABILIZES THE ATMOSPHERE AND LK BREEZE BNDRYS PROVIDE SOME LLVL FOCUS. TENDED TO RAISE FCST MAX TEMPS A FEW DEGREES TO ACCOUNT FOR SOME BREAKS IN THE CLDS MOVING NE FM WI AND ABSENCE OF DYNAMIC FORCING OVER MOST OF THE FA. THE ONLY EXCEPTION WAS THE E... WHERE MORE CLDS STREAMING NWD THRU LWR MI MIGHT HOLD DOWN THE DIURNAL TEMP INCRS. EVEN THOUGH WARMING/DRYING ABV H6 WITH THE ARRIVAL OF THE NEGATIVE DYNAMICS SETS IN AFT 18Z AND WL LIMIT POTENTIAL FOR DEEP CNVCTN...MODIFIED NAM FCST SDNG FOR THE INTERIOR W FOR SFC T/TD OF 75/57 YIELDS SBCAPE NEAR 450 J/KG AND KINX OF 33. GOING CHC POPS/SCHC OF TS LOOKS TO BE IN PRETTY GOOD ORDER. TNGT...IN THE ABSENCE OF ANY DYNAMIC SUPPORT...EXPECT DIURNAL SHRA OVER MAINLY THE W HALF TO DIMINISH THIS EVNG WITH LOSS OF DAYTIME HEATING. ALTHOUGH ANOTHER SHRTWV IS PROGGED TO RACE EWD ALONG THE CNDN BORDER THRU TNGT IN THE FAST WLY FLOW ON THE SRN FLANK OF THE SASKATCHEWAN CLOSED LO AND APRCH THE NW CWA LATER WITH SOME DPVA/DEEP LYR QVECTOR CNVGC...FAIRLY DRY MID LVLS/LLVL ACYC FLOW/ ABSENCE OF ANY DIURNAL HEATING WL LIMIT ACCOMPANYING POPS... ESPECIALLY SINCE THE FOCUS OF THE ASSOCIATED FORCING IS FCST TO PASS TO THE N. DID RETAIN SOME CHC POPS OVER THE NW CWA TO ACCOUNT FOR THIS DISTURBANCE. OTRW...EXPECT SOME FOG TO FORM OVER THE INTERIOR WITH THE MID LVL DRYING/LGT WINDS...ESPECIALLY IN AREAS WHERE SOME RA MIGHT FALL THIS AFTN AND FURTHER MOISTEN THE LLVLS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 412 AM EDT MON JUN 10 2013 LARGER SCALE PATTERN BY TUESDAY INDICATES STRING OF TROUGHS ACROSS CANADA AND TROUGHING OVER NORTHWEST CONUS AND NORTHEAST CONUS. SHALLOW RIDGING IS ANCHORED OVER SOUTH CENTRAL CONUS. THROUGH REST OF THE WEEK TROUGHING OVER CANADA SPLITS WITH RIDGING ATTEMPTING TO BUILD INTO CANADIAN PRAIRIES. EVENTUALLY THIS RIDGE MOVES EAST INTO NORTHERN PLAINS AND UPPER GREAT LAKES BY START OF NEXT WEEKEND. YET ANOTHER TROUGH WILL THEN SWING BACK ACROSS UPPER LAKES TO CLOSE THE WEEKEND. OVERALL PATTERN WILL NOT BRING MUCH RAIN TO UPPER LAKES BUT IT ALSO SHOULD NOT BE THAT COLD EITHER AS BULK OF COLDER AIR STAYS LOCKED UP OVER WESTERN AND EASTERN CANADA CLOSER TO MORE PERSISTENT TROUGHING. TEMPS INLAND FROM LK SUPERIOR AND NEAR LK MICHIGAN MOST DAYS WILL BE AT OR ABOVE NORMAL. TEMPS ALONG LK SUPERIOR WILL BE AT OR SLIGHTLY BLO NORMAL MOST OF THE TIME SINCE PREVAILING WINDS WILL BE ONSHORE. WARMEST DAYS WILL BE TUESDAY AND AGAIN ON SATURDAY WITH MOST AREAS WELL INTO THE 70S. COOLEST DAY THIS WEEK FOR ALL AREAS SHOULD BE ON THURSDAY WHEN TEMPS ALONG LK SUPERIOR WILL LIKELY STAY IN THE 50S. WEAK SHORTWAVE TROUGH AND POCKET OF H85-H7 MOISTURE SWINGS ACROSS WESTERN AND CENTRAL CWA ON TUESDAY MORNING THEN OVR EASTERN CWA DURING AFTN HOURS. THOUGH SHARPEST LIFT IN FORM OF H85-H7 Q-VECTOR CONVERGENCE IMPACTS LK SUPERIOR AND ISLE ROYALE/KEWEENAW PENINSULA THROUGH MIDDAY...RIBBON OF LIFT CROSSES REST OF CWA AS WELL. WEAK FORCING AND SUBTLE MOISTENING POINTS TO LOW CHANCE POPS. BUT...KIND OF SIMILAR TO TODAY...COULD SEE ISOLD DAYTIME SHRA AND EVEN TSRA AS SFC CAPES POP UP TO 300-500J/KG OVR SCNTRL IN THE AFTN. H7-H5 WINDS 45-55KT RESULTING IN DEEP LAYER SHEAR OVR 30 KTS. DO NOT EXPECT THERE TO BE ENOUGH INSTABILITY TO TAKE ADVANTAGE OF THE STRONGER SHEAR THOUGH SO DO NOT EXPECT ANY STRONG STORMS. DEEP DRYING IN H7 LAYER QUICKLY ENDS ANY SHRA/TSRA BY LATE TUE AFTN. H7 DRYING AND NEUTRAL HEIGHTS SHOULD KEEP CONDITIONS DRY THROUGH REST OF TUESDAY NIGHT. ON WEDNESDAY...SHORTWAVE TROUGH SLIDES FROM ROCKIES TOWARD UPPER MISSISSIPPI RIVER VALLEY. SFC LOW/WARM FRONT SET UP FROM NEB INTO NORTHERN IL WHILE H85 WARM FRONT IS NOT MUCH FARTHER THAN THAT. EDGE OF H7 MOISTURE MIGHT MAKE IT INTO NORTHERN WI...BUT SINCE 1-6KM MUCAPE IS BARELY INTO SOUTHERN MN AND CNTRL WI...HAVE HARD TIME THINKING THAT THE INCREASE IN H7 MOSITURE WOULD RESULT IN NOTHING MORE THAN A FEW SPRINKLES OUT OF A SCT-BKN MID CLOUD DECK. NOT WORTH PUTTING ANY POPS INTO SOUTHERN CWA. OTHER THING TO WATCH ON WEDNESDAY IS SHORTWAVE TIED INTO NORTHERN STREAM TROUGH PUSHING INTO ONTARIO. TREND IS FOR WAVE TO BE STRONGER...BUT MAJORITY OF MODELS KEEP WAVE ON WNW-ESE TRACK OVER NORTHERN LK SUPERIOR IN THE MORNING AND OVER ONTARIO EAST OF SAULT STE MARIE BY AFTN. SFC BASED INSTABILITY AND STEEPER H7-H5 LAPSE RATES SHOULD SPUR ON SCATTERED SHRA/TSRA NORTH AND EAST OF LK SUPERIOR WITH DAYTIME HEATING. ONLY THE GEM-NH SHOWS THE WAVE DIGGING ENOUGH SOUTH TO HAVE ANY QPF OVR UPR MICHIGAN THOUGH AND THAT IS ONLY OVR FAR EAST CWA. MAJORITY RULES FOR NOW SO HAVE NOT PUT ANY POPS IN OVER THE EAST. MAX TEMPS MAY SHOW VARIATION CLOSER TO LK SUPERIOR AS LAKE COOLING IS ENHANCED BY AFTN WITH DEVELOPING NORTH GRADIENT FLOW. MAY SEE TEMPS QUICKLY RISE WEDNESDAY MORNING CLOSER TO LK SUPERIOR THEN FALL OFF IN THE AFTN. FARTHER INLAND...EXPECT ANOTHER DAY WITH HIGHS INTO THE 70S. SHORTWAVE PASSAGE RESULTS IN H85-H7 WINDS VEERING MORE NORTH LATER WEDNESDAY NIGHT INTO THURSDAY. H85 THERMAL TROUGH ALSO PRESENT. NOT EXPECTING ANY SHRA AS FORCING IS MINIMAL...BUT MAY SEE DECENT CLOUD COVER IN THE MORNING. BY AFTN...H85 RH PROGS SHOWING LAKE STABILIZING SIGNAL WITH MINIMUM RH SHOWING UP OVR LK SUPERIOR AFT 18Z. PROBABLY WILL SEE CLEARING DEVELOP CLOSER TO LK SUPERIOR AND OVER EAST DUE TO STABILIZING FLOW. EVEN WITH CLEARING WILL BE COOL DAY ALONG LK SUPERIOR AS MOST LOCATIONS STAY IN THE 50S WITH STIFF NORTHERLY WINDS. INLAND TEMPS WILL BE IN THE UPR 60S TO PERHAPS LOWER 70S. HIGH PRESSURE BUILDS ACROSS THURSDAY NIGHT THROUGH FRIDAY AND NOW EVEN THROUGH MOST OF FRIDAY NIGHT. MOSTLY CLEAR SKIES WILL PREVAIL AND GIVEN TREND OF HIGH STAYING AROUND LONGER...FRIDAY NIGHT NOW LOOKING GENERALLY FREE OF ANY SHRA/TSRA EXCEPT FAR WEST CWA. WEEKEND FORECAST MUDDLED AS MID CONUS RIDGE FLATTENS OUT FROM NORTHERN PLAINS TO UPPER GREAT LAKES. STRONGER SHORTWAVE TROUGHS CUTTING THROUGH THE RIDGE FORECAST TO BE OVR CNTRL CANADA AND OVR THE MIDDLE MISSISSIPPI RIVER VALLEY. TALKING DAY 6 AND 7 SO HARD TO GET TOO HUNG UP ON THESE TYPE OF DETAILS YET. OVERALL THEME THOUGH IS SLOWER ARRIVAL OF SHRA/TSRA CHANCES AND/OR A GENERAL LACKING FOCUS FOR SHRA/TSRA. CONSENSUS POPS IN THE LOW CHANCE RANGE USED BUT DID PULL POPS OVER EASTERN CWA ON SATURDAY AS THAT AREA IS IN CLOSER PROXIMITY OF STUBBORN SFC RIDGING. TEMPS FOR NEXT WEEKEND SHOULD BE SIMILAR TO READINGS THIS WEEK WITH HIGHS MAINLY IN THE 70S AND POSSIBLY WARMER IF THERE ARE LESS CLOUDS/SHRA/TSRA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 725 AM EDT MON JUN 10 2013 WITH SOME MORNING SUNSHINE/VFR CONDITIONS...EXPECT SOME SHRA TO DEVELOP WITH THE DAYTIME HEATING AND IMPACT MAINLY IWD AND SAW BEFORE THE SHRA DISSIPATE BY 00Z WITH WANING DAYLIGHT. A WEAK HI PRES WILL MOVE IN THIS EVNG...AND WITH LGT WINDS AND JUST SOME PATCHY HI CLDS...SETUP LOOKS GOOD FOR SOME FOG TO FORM. IFR CONDITIONS APPEAR LIKELY OVERNGT. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 AM EDT MON JUN 10 2013 AS LO PRES IN THE LOWER GREAT LAKES SHIFTS SLOWLY TO THE E TODAY... EXPECT E-SE WINDS UP TO 20 KTS TO SLOWLY DIMINISH W-E WITH THE WEAKENING PRES GRADIENT AND UNDER 15 KTS TONIGHT. DID MAINTAIN PATCHY FOG OVER MUCH OF THE WESTERN LAKE WHERE SOME SHOWERS HAVE FURTHER MOISTENED THE LOW LEVELS. THE WEAK PRES GRADIENT WILL PREVAIL THRU FRI...SO PLAN ON WINDS UNDER 15 KTS TUE THRU FRI. COULD BE A BRIEF PERIOD OF STRONGER WINDS...UP TO 20 KTS IN GUSTS...LATE WEDNESDAY NIGHT AND THURSDAY MORNING. RELATIVELY MOIST AIR OVER THE STILL CHILLY LAKE WATERS WILL RESULT IN LINGERING FOG PATCHES UNTIL DRIER AIR ARRIVES ON FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC/JLA
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
937 AM MDT MON JUN 10 2013 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH WEDNESDAY... SENT AN UPDATE THIS MORNING TO CUT BACK POPS NOW THAT THE PRECIPITATION FROM VERY EARLY THIS MORNING OVER OUR EASTERN AND NORTHEASTERN ZONES HAS MOVED OUT OF OUR CWA. A VERY CALM AND COMFORTABLE SPRING DAY EXPECTED ACROSS NORTHEAST MONTANA. BMICKELSON PREVIOUS SHORT TERM DISCUSSION...SHOWER ACTIVITY VERY EARLY THIS MORNING CONTINUES ACROSS EASTERN SECTIONS OF THE FORECAST AREA. MUCH OF THE MODEL GUIDANCE HAS THIS PUSHING OUT BY 12Z HOWEVER...RECENT RUNS OF THE HRRR HAVE KEPT SPOTTY SHOWERS AROUND FOR A FEW MORE HOURS. THUS...TO COVER THIS POTENTIAL INSERTED A SLIGHT CHANCE POPS MENTION INTO THE GRIDS IN THE EASTERN ZONES. ANY SHOWERS LEFT OVER FROM EARLY THIS MORNING SHOULD QUICKLY MOVE OUT AND BECOME REPLACED BY SUNNY SKIES BY THE AFTERNOON AS NORTHEAST MONTANA BECOMES INFLUENCED BY THE NORTHERN PERIPHERY OF AN UPPER LEVEL RIDGE. THIS WILL INDUCE LARGE SCALE SUBSIDENCE AND PREVENT ANY ADDITIONAL SHOWER ACTIVITY FROM FLARING UP. WILL EXPECT SEASONABLE TEMPERATURES AS WELL WITH THE EARLY JUNE SUNSHINE GOING TO WORK AND RISING 500MB HEIGHTS WITH THE RIDGING BUILDING IN. MONDAY NIGHT...A REGIME OF SOUTHWEST FLOW ALOFT BECOMES ESTABLISHED OVER NORTHEAST MONTANA AS AN UPPER LEVEL SHORTWAVE FEATURE TRANSLATES INTO THE AREA. PVA OUT AHEAD OF THIS WAVE AND UPPER LEVEL DIFFLUENCE WILL PROMOTE FORCED VERTICAL ASCENT. LOW LEVEL SOUTHEASTERLY FLOW WILL ALSO BRING MOISTURE INTO THE FORECAST AREA. MODELS CONTINUE TO HAVE DISAGREEMENT HOWEVER ON THE POTENTIAL FOR SHOWERS/STORMS MONDAY NIGHT INTO TUESDAY APPROACHING FROM THE SOUTH. THE GFS HAS A BAND IN THE SOUTHERN ZONES OVERNIGHT...BUT HAS IT DISSIPATING OVER THE AREA ON TUESDAY. THE ECMWF IS MUCH MORE SUPPORTIVE OF CONVECTION AND GIVEN THE OVERALL PATTERN AND ARGUMENTS ABOVE LEANED TOWARD THIS SOLUTION FOR NOW WILL NOTE THAT THE LATEST ECMWF INDICATES GOOD SURFACE CONVERGENCE IN THE SOUTHWESTERN AND CENTRAL ZONES. THIS LIKELY CORRESPONDS TO A THERMAL TROUGH THAT EXTENDS FROM A SURFACE LOW EXPECTED TO BE LOCATED OVER NORTHEAST WYOMING AT THIS TIME. SHOULD CONVECTION PUSH INTO THE CWA DURING THE DAY ON TUESDAY...THIS TROUGH AXIS COULD SERVE AS A FOCAL POINT FOR ADDITIONAL CONVECTIVE INITIATION. WEDNESDAY...AN ADDITIONAL VIGOROUS SHORTWAVE APPROACHES FROM THE SOUTHWEST WHICH WILL BRING THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS WITH IT. AS IT PUSHES INTO A NICE THETA-E RIDGE THAT SETS UP ACROSS THE SOUTHWESTERN ZONES. THE LATEST 00Z MODEL GUIDANCE INDICATES THAT THE BEST CHANCES FOR CONVECTIVE INITIATION WOULD BE ACROSS WESTERN/CENTRAL ZONES. THE LATEST ECMWF HAS UPWARDS OF 1500 J/KG OF CAPE...WITH THE GFS A LITTLE MORE ROBUST. FORECAST SOUNDINGS ALSO SHOW A NICE VEERING WIND PROFILE INDICATING PLENTY OF DIRECTIONAL WIND SHEAR. THIS WILL COMBINE WITH UPPER LEVEL DIFFLUENCE AND LOW LEVEL MOISTURE TO PRODUCE A GOOD POTENTIAL FOR CONVECTION. GIVEN PRECIPITABLE WATER VALUES OF OVER AN INCH...LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. THE ECMWF SOLUTION IS MUCH FURTHER WEST...WITH THE GFS MORE AGGRESSIVE BRINGING THE PRECIPITATION CHANCES THROUGH MOST OF THE CWA BY 00Z THURSDAY. GIVEN THESE DIFFERENCES...WAS NOT CONFIDENT ENOUGH JUST YET TO INSERT A MENTION OF HEAVY RAIN INTO THE GRIDS JUST YET...BUT A WETTING RAIN IS CERTAINLY POSSIBLE WITH THESE STORMS...ESPECIALLY IN THE WEST. WILL LET THE DAY SHIFT EVALUATE THAT MORE CLOSELY AND SEE IF THERE IS DECENT MODEL CONTINUITY OR IF SOLUTIONS ARE LINING UP BETTER. AM CONCERNED ABOUT CAPPING INVERSION IN THE CENTRAL AND EASTERN ZONES AS THERE IS UPWARDS OF 200-400 J/KG OF CIN PRESENT IN SOME OF THE GUIDANCE. THIS LENDS FURTHER SUPPORT TO THE IDEA OF THE BEST CHANCES BEING ACROSS THE WEST...AT LEAST INITIALLY. NOTE THAT BEST LOW LEVEL CONVERGENCE ACROSS THE WESTERN ZONES DURING THE DAY ON WEDNESDAY IS DEPICTED TO SHIFT EASTWARD BY THE LATE AFTERNOON. THUS...STORMS MAY INITIATE ACROSS THE WEST AND THEN PUSH EASTWARD. IT IS NOTEWORTHY THAT GIVEN HEAVY RAINFALL POTENTIAL WITH ANY STORMS THAT DO DEVELOP...FUTURE SHIFTS WILL NEED TO EVALUATE THE FLOODING POTENTIAL DUE TO RECENT RAINFALL OVER THE LAST COUPLE OF WEEKS. MALIAWCO .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... THE EXTENDED WITH THE 00Z SUITE OF MODELS IN KEEPS THE AREA IN A VERY TYPICAL JUNE PATTERN THROUGH THE WHOLE PERIOD. WHICH LEADS TO A HIGH LEVEL OF PREDICTABILITY OF THE PATTERN...HOWEVER IT ALL WILL BE IN THE TIMING OF INDIVIDUAL WAVES MOVING THROUGH THE FLOW FOR THUNDERSTORM CHANCES. CLIMO POP FOR THIS TIME OF YEAR IS AT ITS HIGHEST WITH CHANCE LEVEL POPS. WEDNESDAY NIGHT...SOUTHWEST FLOW ALOFT AND SURFACE TROUGH TO THE WEST SHOULD SET UP FOR A FEW THUNDERSTORMS ACROSS THE AREA. UPPER LEVEL SUPPORT IS NOT THAT GREAT FOR SEVERE TYPE CONVECTION. THURSDAY-THURSDAY NIGHT BRINGS MORE OF THE SAME...EC DOES HINT THAT WE COULD GET A LITTLE JET DYNAMICS TO HELP OUT FOR A CHANCE FOR SOME STRONGER THUNDER. FRIDAY-FRIDAY NIGHT...SURFACE TROUGH PUSHES EAST WITH GOOD DRYING ALOFT SO WILL RELAX BACK BELOW CLIMO FOR POPS. SATURDAY-SATURDAY NIGHT...PREFER THE EC OVER THE GFS KEEPING NORTHEAST MONTANA MOSTLY DRY...STILL CYCLONIC FLOW COULD HAVE AN ISOLATED THUNDERSTORM OUT THERE. SUNDAY-SUNDAY NIGHT...RIDGING ALOFT SHOULD KEEP ANY THUNDER ACTIVITY LIMITED FOR THE REGION. MONDAY-MONDAY NIGHT...PATTERN STARTS BACK INTO THE SOUTHWEST FLOW ALOFT...SURFACE SOUTHEAST FLOW FOR CHANCE OF CONVECTION AGAIN. TEMPERATURES FAIRLY SEASONAL THROUGH THE WHOLE PERIOD. PROTON && .AVIATION... VFR. A SMALL CHANCE EXISTS THIS AFTERNOON SOUTH OF THE MISSOURI RIVER FOR SOME BRIEF THUNDER... OTHERWISE A GOOD FLYING DAY FOR NORTHEAST MONTANA EXPECTED. PROTON && .HYDROLOGY... FLOOD WARNINGS REMAIN IN EFFECT FOR PORTIONS OF THE MILK RIVER DRAINAGE BASIN STRETCHING FROM TAMPICO TO THE EAST SIDE OF GLASGOW. THE MILK RIVER CRESTING AT SACO. IT IS HOLDING STEADY OR EXPECTED TO CREST OVER THE NEXT FEW DAYS AT THE DOWNSTREAM LOCATIONS OF TAMPICO... GLASGOW AND NASHUA. RUNOFF FROM EARLIER RAINS IS STILL WORKING ITS WAY DOWN BEAVER CREEK IN PHILLIPS COUNTY SOUTH OF SACO. THE GAGE SITE NEAR GUSTON COULEE SOUTHWEST OF SACO IS JUST BELOW THE FLOOD STAGE OF 11 FEET AND FALLING VERY SLOWLY. A FLOOD WARNING CONTINUES FOR BEAVER CREEK. ANOTHER ROUND OF HEAVY RAIN IS POSSIBLE MIDWEEK WHICH COULD CREATE ADDITIONAL FLOODING PROBLEMS ACROSS NORTHEAST MONTANA FOR LATE THIS WEEK. EBERT && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1056 AM EDT MON JUN 10 2013 .SYNOPSIS... WEAK HIGH PRESSURE WILL DRIFT AWAY FROM THE REGION ALLOWING AN AREA OF LOW PRESSURE TO MOVE IN FROM THE OHIO VALLEY. THIS LOW WILL SLOWLY CROSS THE REGION TODAY AND TUESDAY WITH WIDESPREAD RAIN AND PERHAPS A FEW THUNDERSTORMS. DRY WEATHER WILL RETURN WEDNESDAY AND SHOULD CONTINUE THROUGH THE REST OF THE WEEK AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. && .NEAR TERM /THROUGH TONIGHT/... A MID LEVEL LOW AND ASSOCIATED SURFACE LOW WILL PUSH INTO THE OHIO VALLEY TODAY. AHEAD OF THESE FEATURES...MATURING LOW LEVEL JET WILL EFFICIENTLY TRANSPORT MOIST SUBTROPICAL AIRMASS NORTHWARD...WITH ANOMALOUS PRECIPITABLE WATER VALUES SURGING INTO THE REGION. NORTHWARD LIFTING SURFACE WARM FRONT WILL ENHANCE RAINFALL POTENTIAL. ALL RESULTING IN A WIDESPREAD SOAKING RAINFALL FOR WESTERN AND CENTRAL NEW YORK THROUGH TONIGHT. WPC QPF THROUGH TONIGHT SHOWING WIDESPREAD AMOUNTS AROUND ONE INCH. HOWEVER...SOME OF THE HIGHER RESOLUTION GUIDANCE WOULD SUPPORT AMOUNTS UP TO TWO INCHES POSSIBLE. AMOUNTS THIS HIGH WOULD LIKELY ONLY BE POSSIBLE IF WE CAN GET SOME TRAINING CONVECTIVE ELEMENTS. SURFACE BASED INSTABILITY WILL BE GREATLY LACKING IN ABUNDANT CLOUD COVER AND SHOWERS...BUT SOME ELEVATED INSTABILITY IS PRESENT. THERE ALSO MAY BE ENHANCEMENT ALONG A CONVERGENCE BOUNDARY ACROSS THE NIAGARA FRONTIER...BUT THE HRRR AND MOST MODEL GUIDANCE HAS THIS BOUNDARY NORTH OF THE BUFFALO CREEK BASINS. CONSIDERING THE WET SOIL CONDITIONS THERE MAY BE SOME NUISANCE HYDROLOGIC CONCERNS THAT WILL NEED TO BE MONITORED...BUT AT THIS POINT WIDESPREAD FLOODING IS NOT ANTICIPATED. WILL CONTINUE TO MENTION THREAT IN HWO PRODUCT. OTHERWISE...TEMPERATURES WILL ONLY RISE MODESTLY THIS AFTERNOON WITH HIGHS RANGING FROM THE UPPER 60S TO LOWER 70S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... THE BULK OF THE RAIN WILL MOVE OFF TO THE NORTH AND EAST AS THE SURFACE LOW CROSSES NEW YORK STATE DURING TUESDAY. WILL SEE SOME REGENERATION OF THE LOW ACROSS NORTHERN NY AND NEW ENGLAND ON TUESDAY NIGHT AS THE UPPER LOW DEEPENS WHEN IT INTERCEPTS ANOTHER JET STREAK. WILL HAVE LINGERING LIKELY POPS ACROSS THE LOWER SAINT LAWRENCE VALLEY...ON THE RIVER BUT OUTSIDE OF OUR FORECAST AREA...AND WANING CHANCE POPS FOR THE REST OF THE FORECAST AREA FOR TUESDAY NIGHT. AN UNSETTLED UPPER LEVEL PATTERN WILL KEEP THE NEED FOR CHANCE POPS DURING WEDNESDAY AS A SERIES OF WAVES AND VORTICITY MAXIMA ALOFT STREAM BY IN THE NORTHWESTERLY FLOW. WEAK LOW PRESSURE PASSING BY TO THE SOUTH WILL BRING SOME HIGHER CHANCE POPS ACROSS THE SOUTHERN TIER FOR WED AFTERNOON AND EVENING. A WEAK REGION OF HIGH PRESSURE WILL SETTLE OVER NEW YORK STATE WEDNESDAY NIGHT WITH A CLEARING TREND AND BREAK FROM THE RAIN CHANCES. TEMPERATURES WILL BE SLIGHTLY BELOW NORMAL ON TUESDAY AS THE DEPARTING LOW DRAWS DOWN SOME MARGINALLY COOLER AIR IN ITS WAKE. HIGHS WILL BE IN THE MID 60S ACROSS THE NORTH COUNTRY TO THE UPPER 60S AND LOW 70S ELSEWHERE. LOWS TUESDAY NIGHT IN THE MID TO UPPER 50S WILL REFLECT THE REMNANT MOISTURE FROM THE PREVIOUS RAINFALL AND LACK OF ANY REAL AIRMASS CHANGE FOLLOWING THE DEPARTURE OF THE SURFACE LOW. AN INFLUX OF WARMER AIR ALONG AND AHEAD OF WEAK LOW PRESSURE WILL BUMP HIGH TEMPS UP A BIT ON WEDNESDAY WITH HIGHS IN THE LOWER 70S ACROSS THE NORTH COUNTRY AND THE MID 70S ELSEWHERE. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ON THURSDAY...A WEAK SURFACE RIDGE SHOULD BE IN PLACE OVER NY...WITH DRY WEATHER EXPECTED. A BACK DOOR COLD FRONT MAY MOVE ACROSS THE NORTH COUNTRY ON FRIDAY...BUT OTHER THAN KNOCK OFF A FEW DEGREES FROM DAYTIME HIGHS...THIS SHOULD HAVE LITTLE IF ANY EFFECT ON THE WEATHER. HIGH PRESSURE HAS BEEN FORECAST FOR DAYS NOW OVER THE STATE FOR SATURDAY FOR A HIGH CONFIDENCE DRY DAY. SUNDAY IS NOT QUITE LOCKED IN HOWEVER...WITH SEVERAL MODELS BRINGING THE NEXT ROUND OF SHOWERS INTO THE STATE. THE LATEST GFS HOLDS THIS OFF UNTIL SUNDAY EVENING. FOR TEMPERATURES...WITHOUT ANY PRONOUNCED RIDGING OR TROUGHING OVER THE REGION...EXPECT HIGHS AND LOWS THROUGHOUT THE LATTER HALF OF THE WEEK TO BE WITHIN A FEW DEGREES OF NORMAL. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... AN AREA OF LOW PRESSURE WILL PUSH INTO THE OHIO VALLEY TODAY. INCREASING MOISTURE AND ASCENT AHEAD OF THIS FEATURE WILL BRING SHOWERS INTO WESTERN NY THROUGH THIS EVENING. INITIALLY...THE SE FLOW WILL HELP KEEP VFR CIGS THROUGH EARLY AFTERNOON AT BUF/IAG/ROC DUE TO THE DOWNSLOPE WIND DIRECTION. BY MID- AFTERNOON...STEADIER SHOWERS WILL MOVE IN...WITH INCREASING MOISTURE. CIGS SHOULD GRADUALLY LOWER...WITH HEAVIER SHOWERS AND POSSIBLY A THUNDERSTORM EMBEDDED. THE LOW WILL LIFT ACROSS THE REGION TONIGHT...WITH WINDS SHIFTING WITH THE PASSAGE OF THE LOW. THIS WIND SHIFT WILL KEY A DROP IN CIGS...WITH A PERIOD OF IFR CONDITIONS LIKELY AT MOST SITES. AHEAD OF THE LOW...EXPECT LIFR CONDITIONS WEST OF LAKE ONTARIO...BUT AT THIS TIME IT APPEARS THE SE FLOW WILL HOLD AT OUR TAF LOCATIONS...WITH IAG THE ONLY CLOSE CALL. OUTLOOK... TUESDAY...MVFR WITH SHOWERS. WEDNESDAY...MVFR IMPROVING TO VFR. THURSDAY AND FRIDAY...MAINLY VFR. && .MARINE... EASTERLY WINDS WILL INCREASE TODAY AHEAD OF AN AREA OF LOW PRESSURE PUSHING INTO THE OHIO VALLEY..PRODUCING SOME CHOPPY WAVE CONDITIONS ON WESTERN LAKE ONTARIO ALTHOUGH CONDITIONS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THIS LOW WILL PASS JUST NORTH OF THE REGION TUESDAY AND COULD POSSIBLY PRODUCE A BRIEF PERIOD OF SMALL CRAFT CONDITIONS ON LAKE ERIE AS WINDS FUNNEL DOWN THE LAKE. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA NEAR TERM...APFFEL/TMA SHORT TERM...WCH LONG TERM...ZAFF AVIATION...APFFEL/TMA MARINE...APFFEL/TMA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
752 AM EDT MON JUN 10 2013 .SYNOPSIS... SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN ARE EXPECTED TODAY AHEAD OF A WEAKENING COLD FRONT. ABOVE NORMAL TEMPERATURES WILL DEVELOP TUESDAY THROUGH THURSDAY. ANOTHER COLD FRONT WILL MOVE ACROSS LATE THURSDAY NIGHT. DRY AND RELATIVELY COOL HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 645 AM MONDAY...EACH SUCCESSIVE RUN OF THE HRRR PAINTS A DIFFERENT VERSION OF THE SAME STORY: DAYTIME HEATING IS GOING TO IGNITE A LARGE NUMBER OF SHOWER AND THUNDERSTORM CLUSTERS ACROSS THE CENTRAL AND EASTERN CAROLINAS TODAY. GIVEN LOW LEVEL WINDS BLOWING ONSHORE...THE IMMEDIATE BEACHES WILL SEE A MINIMA IN PRECIPITATION COVERAGE ONCE THE SEABREEZE HAS BEGUN BLOWING BY LATE MORNING. THE HIGHEST COVERAGE OF CONVECTION...80-90 PERCENT...IS STILL ANTICIPATED ALONG AND WEST OF INTERSTATE 95. I HAVE TWEAKED FORECAST HIGHS UP A DEGREE IN SPOTS...OTHERWISE NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION FROM 330 AM FOLLOWS... MID-JUNE IS SUPPOSED TO BE THE TIME OF THE YEAR WHEN THE MID-LATITUDE STORM TRACK PULLS NORTH TOWARD THE CANADIAN BORDER AND WE MOVE INTO A TROPICAL PATTERN GOVERNED BY MARITIME FLOW OFF THE ATLANTIC...DAILY SEA BREEZES AND AFTERNOON THUNDERSTORMS. NOT SO TODAY AT LEAST: AN IMPRESSIVE UPPER TROUGH OVER ILLINOIS WILL MOVE EAST ACROSS THE CENTRAL APPALACHIANS TONIGHT...DRIVING A SURFACE COLD FRONT EASTWARD INTO THE EASTERN CAROLINAS. AHEAD OF THIS FRONT WE HAVE A MARITIME TROPICAL AIRMASS WITH PRECIPITABLE WATER NEAR 2.0 INCHES AND SURFACE DEWPOINTS IN THE 70S. WITH THE LOW LEVEL FLOW ALMOST IDENTICAL IN SPEED AND DIRECTION TO THE 850-300 MB STEERING FLOW...WHAT COULD ALMOST BE TERMED A REGENERATIVE MCS WAS THE RESULT SUNDAY EVENING ACROSS PENDER COUNTY WITH RADAR ESTIMATES OF 4-7 INCHES OF RAIN BETWEEN BURGAW AND MOORES CREEK BATTLEFIELD. ALTHOUGH A BROADLY DIFFLUENT UPPER PATTERN EXISTS ACROSS THE AREA DUE TO A JET STREAK CURRENTLY OVER NEW ENGLAND AND A SECOND JET STREAK DEVELOPING ACROSS THE MID-ATLANTIC TONIGHT...THE 925 MB LOW LEVEL JET SHOULD NOT KEEP UP WITH INCREASES IN THE WIND SPEEDS ALOFT. THIS DISPARITY SHOULD FAVOR FORWARD-PROPAGATING CELLS AND FASTER OVERALL STORM MOTION ON THE ORDER OF 25-30 MPH TODAY. FORECAST RAINFALL THROUGH TONIGHT RANGES FROM 1.25 INCHES ALONG THE I-95 CORRIDOR TO 0.6 INCHES ON THE NC COAST...WITH POPS 80 PERCENT OR HIGHER ALONG AND WEST OF INTERSTATE 95. ALTHOUGH A FLOOD WATCH WAS CONTEMPLATED...TODAY`S FASTER CELL MOTION SHOULD HELP REDUCE THE POTENTIAL FOR EXCESSIVE (3+ INCH) RAINFALL TOTALS AT ANY ONE LOCATION...CONFIRMED BY LOW NUMBERS IN THE SREF 24 HOUR 1" AND 2" RAINFALL PROBABILITIES. THE SURFACE COLD FRONT SHOULD MOVE INTO THE AREA FROM WEST TO EAST LATE TONIGHT. MODELS ARE NOT SHOWING THIS FRONT CLEANLY MOVING OFFSHORE...THEREFORE I CANNOT SHOW A PRONOUNCED CLEARING OR DRYING TREND IN THE FORECAST EVEN LATE TONIGHT. THE HIGHEST POPS SHOULD TRANSITION EAST OF INTERSTATE 95 DURING THE EVENING HOURS... APPROACHING THE COAST BY MIDNIGHT WHERE I HAVE 60 POPS FORECAST AT MYRTLE BEACH AND WILMINGTON. SOME DRIER AIR WILL ARRIVE ALOFT BY MIDNIGHT AS THE STEERING FLOW ACQUIRES A MORE WESTERLY COMPONENT... AND THE POTENTIAL FOR HEAVY RAIN WILL DIMINISH. IN BETWEEN CLOUDS AND SHOWERS TODAY`S HIGHS SHOULD REACH THE MID 80S IN MOST AREAS. LOWS TONIGHT WILL RANGE FROM 69-73...WARMEST AT THE COAST. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY... MUCH DRIER AIR WILL ADVECT INTO THE AREA THROUGH TUESDAY AS FLOW ALOFT SHIFTS AROUND TO THE WEST AND NORTHWEST AHEAD OF ACTUAL ARRIVAL OF SURFACE FRONT BY WED MORNING. PCP WATER VALUES WILL BE DOWN LESS THAN 1.5 INCHES AS LOW TO MID LEVEL TROUGH EXITS THE COAST. WITH SUBSIDENCE AND DRY AIR ON THE BACK END EXPECT ANY LINGERING PCP TO DIMINISH THROUGH THE DAY. RESIDUAL MOISTURE FROM RAIN ON MONDAY WILL PRODUCE CU AND MAY SEE ENOUGH CONVERGENCE ALONG THE SEA BREEZE TO PRODUCE A SHOWER OR TWO THROUGH THE AFTN...BUT OVERALL ALL SHWRS SHOULD END EARLY IN THE DAY. BEST CHC OF PCP LATER IN THE DAY WILL BE CLOSER TO THE COAST AS WESTERLY COMPONENT TO FLOW SHOULD KEEP BEST CONVERGENCE CLOSER TO THE COAST...NOT ALLOWING SEA BREEZE TO MOVE TOO FAR INLAND. THE ACTUAL SURFACE FEATURE WILL BECOME DIFFUSE AS IT REACHES THE COAST BY WED MORNING. THE SFC WINDS WILL VEER AROUND TO THE WEST ONLY BRIEFLY BEFORE BACKING TO THE SW AS PIEDMONT TROUGH REMAINS MORE PRONOUNCED INLAND. WITH STRONG WESTERLY COMPONENT TO THE FLOW EXPECT ANY CONVERGENCE ALONG THE SEA BREEZE TO REMAIN CLOSE TO THE COAST. RIDGE BUILDS UP FROM THE GULF BUT A SHORTWAVE ON THE NORTHEAST EDGE OF RIDGE RIDES THROUGH THE LOCAL AREA WED AFTERNOON WHICH COULD HELP TO ENHANCE CU DEVELOPMENT AND POSSIBLY AN ISOLATED SHWR. FOR NOW WILL KEEP ANY POPS OUT OF FORECAST WITH SO MUCH DRY AIR IN PLACE ALOFT. AS FOR TEMPS...THE WESTERLY DOWNSLOPE FLOW WILL ALSO AID IN COMPRESSIONAL WARMING BOTH TUES AND WED PRODUCING TEMPS ABOVE NORMAL...INTO THE 90S MOST PLACES. THE 850 TEMPS RISE THROUGH THE PERIOD FROM AROUND 20C ON WED TO 21C ON THURS. OVERALL EXPECT A VERY WARM MID WEEK. ALTHOUGH A GOOD DEAL OF DRY AIR MAKES IT INTO AREA ALOFT...SFC DEWPOINTS ONLY DROP A COUPLE OF DEGREES...STILL HOLDING UP CLOSER TO 70. THEREFORE OVERNIGHT LOWS WILL REMAIN UP CLOSER TO 70 ALSO. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM MONDAY...MID TO UPPER RIDGE GETS SUPPRESSED TO THE SOUTH AS SHORTWAVE DIGS SOUTH FROM THE GREAT LAKES ON THURS. THIS WHOLE SYSTEM MOVES EAST DRAGGING A COLD FRONT THROUGH THE AREA THURS NIGHT. ALTHOUGH THE SURFACE FLOW IS SOUTHERLY ON THURS THE WINDS ALOFT MAINTAIN MORE OF A WESTERLY DIRECTION. OVERALL DO NOT EXPECT TOO MUCH MOISTURE RETURN THROUGH THE MID TO UPPER LEVELS AND THEREFORE EXPECT MOST OF THE CONVECTIVE ACTIVITY ON THURS TO COME LATER IN THE DAY AS COLD FRONT MAKES ITS WAY THROUGH THE CAROLINAS. THEREFORE WILL KEEP LOW END POPS ASSOCIATED WITH LOCALIZED SHWR ACTIVITY THURS AFTN AND INCREASING CHC OF SHWRS/TSTMS THURS NIGHT AS FRONT MOVES THROUGH. COLD FRONT SHOULD CLEAR THE COAST BY FRI MORNING BUT SOME LINGERING SHWRS ARE POSSIBLE ALONG THE COAST. DEEP NW FLOW OF DRIER AND RELATIVELY COOLER AIR WILL ADVECT IN BEHIND COLD FRONT FRI THROUGH THE WEEKEND AS CANADIAN HIGH PRESSURE BUILDS DOWN. SOME MINOR PERTURBATIONS IN THE MID LEVEL FLOW WILL MOVE OVER THE TOP OF STRONG RIDGE BUILDING UP THROUGH THE CENTRAL CONUS. THIS MAY INDUCE SOME CLOUD DEVELOPMENT BUT OVERALL EXPECT A DRY WEEKEND WITH PLENTY OF SUNSHINE. TEMPERATURES ON THURS WILL REACH WELL INTO THE 90S MOST PLACES AS 850 TEMPS HOLD UP AROUND 21C. ONCE COLD FRONT MOVES THROUGH BY FRI...TEMPS WILL BE KNOCKED BACK DOWN TO NORMAL OR SLIGHTLY BELOW...IN THE MID 80S MOST PLACES THROUGH THE WEEKEND. OVERNIGHT LOWS WILL BE BACK DOWN TO NORMAL AS WELL WITH READINGS IN THE MID 60S. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 12Z...EXPECT IFR/TEMPO MVFR CIGS INLAND TERMINALS TO RISE TO MVFR BY 13-14Z AND REMAIN MVFR THROUGH MUCH OF THIS MORNING AND AFTERNOON. MVFR/TEMPO VFR CIGS CAN BE EXPECTED AT THE COASTAL TERMINALS AS THE SEA BREEZE/RESULTANT BOUNDARY DEVELOPS THIS MORNING. CIGS SHOULD RISE TO MOSTLY VFR WITH LOW CHANCES OF MVFR LATE THIS MORNING PERSISTING INTO THE AFTERNOON AND EARLY EVENING. PER RADAR THERE IS MODERATE CONFIDENCE A TEMPO LIGHT SHOWER COULD OCCUR AT KILM THROUGH 13-14Z. BY 15Z AS THE SEA BREEZE/RESULTANT BOUNDARY INITIALLY STAYS PINNED NEAR THE COAST THERE WILL BE A CHANCE OF SHOWER OCCURRENCE AT ALL COASTAL TERMINALS...BUT CONFIDENCE IS LOWER. SHOWERS SHOULD BE MAINLY INLAND OF THE COASTAL TERMINALS LATE MORNING/EARLY AFTERNOON. EXPECT SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS TO DEVELOP THIS MORNING BETWEEN THE INLAND AND COASTAL TERMINALS. THERE IS MODERATE CONFIDENCE KFLO/KLBT WILL BE AFFECTED BY THIS ACTIVITY FROM MID-MORNING THROUGHOUT THE AFTERNOON...WITH ACTIVITY BECOMING ISOLATED IN THE EVENING AS MOST OF THE CONVECTION SHIFTS TO THE COASTAL TERMINALS. MVFR/TEMPO IFR WILL BE POSSIBLE IN ANY PRECIPITATION. SHOWERS WILL BECOME ISOLATED IN THE PRE-DAWN HOURS AT THE COASTAL TERMINALS AS SLIGHTLY DRIER AIR FILTERS IN. AT KFLO/KLBT IFR/LIFR IN FOG WILL BE POSSIBLE AFTER 09Z. EXTENDED OUTLOOK...ISOLATED SHOWERS/THUNDERSTORMS WITH TEMPO PERIODS OF MVFR/IFR POSSIBLE TUESDAY AND THURSDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 730 AM MONDAY...WINDS APPEAR TO BE STRONGER AT THE BEACHES THAN THEY ARE OFFSHORE AT FRYING PAN SHOALS BUOY. SMALL INITIAL ADJUSTMENTS HAVE BEEN MADE FOR THIS...OTHERWISE THE TREND OF SLOWLY INCREASING WINDS THROUGH TONIGHT REMAINS UNCHANGED. PREVIOUS DISCUSSION FROM 330 AM FOLLOWS... THE PRESSURE GRADIENT BETWEEN BERMUDA HIGH PRESSURE WELL OFFSHORE AND A COLD FRONT ADVANCING EASTWARD ACROSS THE MISSISSIPPI VALLEY WILL CREATE STRENGTHENING SOUTH WINDS TODAY AND TONIGHT. WIND SPEEDS CURRENTLY AROUND 15 KNOTS WILL INCREASE TO 15-20 KNOTS BY EARLY THIS EVENING...VEERING MORE SOUTHWESTERLY WITH TIME TONIGHT. THIS SHOULD LEAD TO BUILDING SEAS...WITH THE POTENTIAL FOR 6 FOOT SEAS ACROSS THE NC WATERS NECESSITATING A SMALL CRAFT ADVISORY FOR THIS AREA TONIGHT THROUGH TUESDAY. SCATTERED SHOWERS THIS MORNING WILL SHIFT MAINLY INLAND BY LATE MORNING...BUT WAVES OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PUSH BACK OFFSHORE THIS EVENING AND OVERNIGHT AS THE COLD FRONT APPROACHES FROM THE WEST. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...WINDS AND SEAS WILL BE CLOSE TO SCA THRESHOLDS AT THE START OF THE SHORT TERM PERIOD. SW WINDS UP TO 15 TO 20 KTS WILL PUSH SEAS UP CLOSE TO 5 TO 6 FT IN OUTER WATERS AND 3 TO 4 FT NEAR SHORE. WILL KEEP WITH SCA FOR NORTHERN 2 MARINE ZONES ONLY THROUGH THE DAY ON TUES. WINDS WILL VEER AROUND AS COLD FRONT APPROACHES LATE TUES INTO EARLY WED. THIS WEAKENING OFF SHORE FLOW AROUND 10 TO 15 KTS WILL ALLOW SEAS TO SUBSIDE DOWN TO 2 TO 4 FT THROUGH WED. WINDS AND SEAS WILL INCREASE AGAIN LATE WED INTO THURS AS GRADIENT TIGHTENS FIRST DUE TO MORE PRONOUNCED PIEDMONT TROUGH INLAND AND THEN DUE TO APPROACH OF COLD FRONT BY THURS. EXPECT SW WINDS BACK UP TO A SOLID 15 KTS OR SO BY THURS MORNING WITH SEAS UP AROUND 4 TO 5 FT IN OUTER WATERS. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 3 AM MONDAY...TIGHTENING GRADIENT FLOW AHEAD OF AN APPROACHING COLD FRONT WILL PRODUCE SW WINDS UP TO 15 TO 20 KTS. MAY EVEN SEA WINDS UP CLOSE TO 25 KTS JUST AHEAD OF COLD FRONT LATE THURS NIGHT INTO EARLY FRI. THIS WILL PUSH SEAS UP TO 6 TO 7 FT IN OUTER WATERS THURS NIGHT. BY FRIDAY...THE WINDS WILL VEER AROUND ABRUPTLY TO THE NW-N BEHIND COLD FRONT AND WILL DIMINISH DOWN TO 10 TO 15 KTS. SEAS WILL DROP BACK DOWN TO 2 TO 4 FT ON FRI. WINDS WILL CONTINUE TO VEER AROUND BECOMING MORE ON SHORE BUT LIGHT THROUGH THE WEEKEND AS HIGH PRESSURE SHIFTS DOWN FROM THE NORTH MOVING CLOSER OVERHEAD OVER THE WEEKEND. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 PM EDT TUESDAY FOR AMZ250-252. && $$ NEAR TERM...TRA SHORT TERM...RGZ LONG TERM...RGZ AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
655 AM EDT MON JUN 10 2013 .SYNOPSIS... SHOWERS AND THUNDERSTORMS WITH HEAVY RAIN ARE EXPECTED TODAY AHEAD OF A WEAKENING COLD FRONT. ABOVE NORMAL TEMPERATURES WILL DEVELOP TUESDAY THROUGH THURSDAY. ANOTHER COLD FRONT WILL MOVE ACROSS LATE THURSDAY NIGHT. DRY AND RELATIVELY COOL HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 645 AM MONDAY...EACH SUCCESSIVE RUN OF THE HRRR PAINTS A DIFFERENT VERSION OF THE SAME STORY: DAYTIME HEATING IS GOING TO IGNITE A LARGE NUMBER OF SHOWER AND THUNDERSTORM CLUSTERS ACROSS THE CENTRAL AND EASTERN CAROLINAS TODAY. GIVEN LOW LEVEL WINDS BLOWING ONSHORE...THE IMMEDIATE BEACHES WILL SEE A MINIMA IN PRECIPITATION COVERAGE ONCE THE SEABREEZE HAS BEGUN BLOWING BY LATE MORNING. THE HIGHEST COVERAGE OF CONVECTION...80-90 PERCENT...IS STILL ANTICIPATED ALONG AND WEST OF INTERSTATE 95. I HAVE TWEAKED FORECAST HIGHS UP A DEGREE IN SPOTS...OTHERWISE NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION FROM 330 AM FOLLOWS... MID-JUNE IS SUPPOSED TO BE THE TIME OF THE YEAR WHEN THE MID-LATITUDE STORM TRACK PULLS NORTH TOWARD THE CANADIAN BORDER AND WE MOVE INTO A TROPICAL PATTERN GOVERNED BY MARITIME FLOW OFF THE ATLANTIC...DAILY SEABREEZES AND AFTERNOON THUNDERSTORMS. NOT SO TODAY AT LEAST: AN IMPRESSIVE UPPER TROUGH OVER ILLINOIS WILL MOVE EAST ACROSS THE CENTRAL APPALACHIANS TONIGHT...DRIVING A SURFACE COLD FRONT EASTWARD INTO THE EASTERN CAROLINAS. AHEAD OF THIS FRONT WE HAVE A MARITIME TROPICAL AIRMASS WITH PRECIPITABLE WATER NEAR 2.0 INCHES AND SURFACE DEWPOINTS IN THE 70S. WITH THE LOW LEVEL FLOW ALMOST IDENTICAL IN SPEED AND DIRECTION TO THE 850-300 MB STEERING FLOW...WHAT COULD ALMOST BE TERMED A REGENERATIVE MCS WAS THE RESULT SUNDAY EVENING ACROSS PENDER COUNTY WITH RADAR ESTIMATES OF 4-7 INCHES OF RAIN BETWEEN BURGAW AND MOORES CREEK BATTLEFIELD. ALTHOUGH A BROADLY DIFLUENT UPPER PATTERN EXISTS ACROSS THE AREA DUE TO A JET STREAK CURRENTLY OVER NEW ENGLAND AND A SECOND JET STREAK DEVELOPING ACROSS THE MID-ATLANTIC TONIGHT...THE 925 MB LOW LEVEL JET SHOULD NOT KEEP UP WITH INCREASES IN THE WIND SPEEDS ALOFT. THIS DISPARITY SHOULD FAVOR FORWARD-PROPAGATING CELLS AND FASTER OVERALL STORM MOTION ON THE ORDER OF 25-30 MPH TODAY. FORECAST RAINFALL THROUGH TONIGHT RANGES FROM 1.25 INCHES ALONG THE I-95 CORRIDOR TO 0.6 INCHES ON THE NC COAST...WITH POPS 80 PERCENT OR HIGHER ALONG AND WEST OF INTERSTATE 95. ALTHOUGH A FLOOD WATCH WAS CONTEMPLATED...TODAY`S FASTER CELL MOTION SHOULD HELP REDUCE THE POTENTIAL FOR EXCESSIVE (3+ INCH) RAINFALL TOTALS AT ANY ONE LOCATION...CONFIRMED BY LOW NUMBERS IN THE SREF 24 HOUR 1" AND 2" RAINFALL PROBABILITIES. THE SURFACE COLD FRONT SHOULD MOVE INTO THE AREA FROM WEST TO EAST LATE TONIGHT. MODELS ARE NOT SHOWING THIS FRONT CLEANLY MOVING OFFSHORE...THEREFORE I CANNOT SHOW A PRONOUNCED CLEARING OR DRYING TREND IN THE FORECAST EVEN LATE TONIGHT. THE HIGHEST POPS SHOULD TRANSITION EAST OF INTERSTATE 95 DURING THE EVENING HOURS... APPROACHING THE COAST BY MIDNIGHT WHERE I HAVE 60 POPS FORECAST AT MYRTLE BEACH AND WILMINGTON. SOME DRIER AIR WILL ARRIVE ALOFT BY MIDNIGHT AS THE STEERING FLOW ACQUIRES A MORE WESTERLY COMPONENT... AND THE POTENTIAL FOR HEAVY RAIN WILL DIMINISH. IN BETWEEN CLOUDS AND SHOWERS TODAY`S HIGHS SHOULD REACH THE MID 80S IN MOST AREAS. LOWS TONIGHT WILL RANGE FROM 69-73...WARMEST AT THE COAST. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY... MUCH DRIER AIR WILL ADVECT INTO THE AREA THROUGH TUESDAY AS FLOW ALOFT SHIFTS AROUND TO THE WEST AND NORTHWEST AHEAD OF ACTUAL ARRIVAL OF SURFACE FRONT BY WED MORNING. PCP WATER VALUES WILL BE DOWN LESS THAN 1.5 INCHES AS LOW TO MID LEVEL TROUGH EXITS THE COAST. WITH SUBSIDENCE AND DRY AIR ON THE BACK END EXPECT ANY LINGERING PCP TO DIMINISH THROUGH THE DAY. RESIDUAL MOISTURE FROM RAIN ON MONDAY WILL PRODUCE CU AND MAY SEE ENOUGH CONVERGENCE ALONG THE SEA BREEZE TO PRODUCE A SHOWER OR TWO THROUGH THE AFTN...BUT OVERALL ALL SHWRS SHOULD END EARLY IN THE DAY. BEST CHC OF PCP LATER IN THE DAY WILL BE CLOSER TO THE COAST AS WESTERLY COMPONENT TO FLOW SHOULD KEEP BEST CONVERGENCE CLOSER TO THE COAST...NOT ALLOWING SEA BREEZE TO MOVE TOO FAR INLAND. THE ACTUAL SURFACE FEATURE WILL BECOME DIFFUSE AS IT REACHES THE COAST BY WED MORNING. THE SFC WINDS WILL VEER AROUND TO THE WEST ONLY BRIEFLY BEFORE BACKING TO THE SW AS PIEDMONT TROUGH REMAINS MORE PRONOUNCED INLAND. WITH STRONG WESTERLY COMPONENT TO THE FLOW EXPECT ANY CONVERGENCE ALONG THE SEA BREEZE TO REMAIN CLOSE TO THE COAST. RIDGE BUILDS UP FROM THE GULF BUT A SHORTWAVE ON THE NORTHEAST EDGE OF RIDGE RIDES THROUGH THE LOCAL AREA WED AFTERNOON WHICH COULD HELP TO ENHANCE CU DEVELOPMENT AND POSSIBLY AN ISOLATED SHWR. FOR NOW WILL KEEP ANY POPS OUT OF FORECAST WITH SO MUCH DRY AIR IN PLACE ALOFT. AS FOR TEMPS...THE WESTERLY DOWNSLOPE FLOW WILL ALSO AID IN COMPRESSIONAL WARMING BOTH TUES AND WED PRODUCING TEMPS ABOVE NORMAL...INTO THE 90S MOST PLACES. THE 850 TEMPS RISE THROUGH THE PERIOD FROM AROUND 20C ON WED TO 21C ON THURS. OVERALL EXPECT A VERY WARM MID WEEK. ALTHOUGH A GOOD DEAL OF DRY AIR MAKES IT INTO AREA ALOFT...SFC DEWPOINTS ONLY DROP A COUPLE OF DEGREES...STILL HOLDING UP CLOSER TO 70. THEREFORE OVERNIGHT LOWS WILL REMAIN UP CLOSER TO 70 ALSO. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM MONDAY...MID TO UPPER RIDGE GETS SUPPRESSED TO THE SOUTH AS SHORTWAVE DIGS SOUTH FROM THE GREAT LAKES ON THURS. THIS WHOLE SYSTEM MOVES EAST DRAGGING A COLD FRONT THROUGH THE AREA THURS NIGHT. ALTHOUGH THE SURFACE FLOW IS SOUTHERLY ON THURS THE WINDS ALOFT MAINTAIN MORE OF A WESTERLY DIRECTION. OVERALL DO NOT EXPECT TOO MUCH MOISTURE RETURN THROUGH THE MID TO UPPER LEVELS AND THEREFORE EXPECT MOST OF THE CONVECTIVE ACTIVITY ON THURS TO COME LATER IN THE DAY AS COLD FRONT MAKES ITS WAY THROUGH THE CAROLINAS. THEREFORE WILL KEEP LOW END POPS ASSOCIATED WITH LOCALIZED SHWR ACTIVITY THURS AFTN AND INCREASING CHC OF SHWRS/TSTMS THURS NIGHT AS FRONT MOVES THROUGH. COLD FRONT SHOULD CLEAR THE COAST BY FRI MORNING BUT SOME LINGERING SHWRS ARE POSSIBLE ALONG THE COAST. DEEP NW FLOW OF DRIER AND RELATIVELY COOLER AIR WILL ADVECT IN BEHIND COLD FRONT FRI THROUGH THE WEEKEND AS CANADIAN HIGH PRESSURE BUILDS DOWN. SOME MINOR PERTURBATIONS IN THE MID LEVEL FLOW WILL MOVE OVER THE TOP OF STRONG RIDGE BUILDING UP THROUGH THE CENTRAL CONUS. THIS MAY INDUCE SOME CLOUD DEVELOPMENT BUT OVERALL EXPECT A DRY WEEKEND WITH PLENTY OF SUNSHINE. TEMPERATURES ON THURS WILL REACH WELL INTO THE 90S MOST PLACES AS 850 TEMPS HOLD UP AROUND 21C. ONCE COLD FRONT MOVES THROUGH BY FRI...TEMPS WILL BE KNOCKED BACK DOWN TO NORMAL OR SLIGHTLY BELOW...IN THE MID 80S MOST PLACES THROUGH THE WEEKEND. OVERNIGHT LOWS WILL BE BACK DOWN TO NORMAL AS WELL WITH READINGS IN THE MID 60S. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 06Z...EXPECT IFR CIGS/VSBYS INLAND AND MVFR/TEMPO IFR CIGS ALONG THE COAST WITH THE SATURATED LOW-LEVEL ENVIRONMENT. TEMPO -SHRA ARE ALSO POSSIBLE ALONG THE COAST THIS MORNING WITH SHOWER ACTIVITY CONTINUING OFFSHORE. SHOWERS AND T-STORMS ARE LIKELY ACROSS THE AREA TODAY WITH AN UPPER DISTURBANCE AHEAD OF A LARGE UPPER TROUGH. EXPECT MVFR/VFR TO PREVAIL THRU THE DAY WITH TEMPO IFR IN HEAVIER DOWNPOURS. S/SW WINDS WILL INCREASE TO 10-15 KTS WITH GUSTS OF 20 KTS DURING THE AFTN HOURS. HAVE CONTINUED VCSH AT ALL TERMS THROUGH THE END OF THE TAF PERIOD AS THE TROUGH/FRONT NEARS THE CWA. EXTENDED OUTLOOK...SHOWERS/T-STORMS WITH PERIODS OF MVFR/IFR THROUGH TUESDAY. CHANCE OF SHOWERS THURSDAY. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 730 AM MONDAY...WINDS APPEAR TO BE STRONGER AT THE BEACHES THAN THEY ARE OFFSHORE AT FRYING PAN SHOALS BUOY. SMALL INITIAL ADJUSTMENTS HAVE BEEN MADE FOR THIS...OTHERWISE THE TREND OF SLOWLY INCREASING WINDS THROUGH TONIGHT REMAINS UNCHANGED. PREVIOUS DISCUSSION FROM 330 AM FOLLOWS... THE PRESSURE GRADIENT BETWEEN BERMUDA HIGH PRESSURE WELL OFFSHORE AND A COLD FRONT ADVANCING EASTWARD ACROSS THE MISSISSIPPI VALLEY WILL CREATE STRENGTHENING SOUTH WINDS TODAY AND TONIGHT. WIND SPEEDS CURRENTLY AROUND 15 KNOTS WILL INCREASE TO 15-20 KNOTS BY EARLY THIS EVENING...VEERING MORE SOUTHWESTERLY WITH TIME TONIGHT. THIS SHOULD LEAD TO BUILDING SEAS...WITH THE POTENTIAL FOR 6 FOOT SEAS ACROSS THE NC WATERS NECESSITATING A SMALL CRAFT ADVISORY FOR THIS AREA TONIGHT THROUGH TUESDAY. SCATTERED SHOWERS THIS MORNING WILL SHIFT MAINLY INLAND BY LATE MORNING...BUT WAVES OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PUSH BACK OFFSHORE THIS EVENING AND OVERNIGHT AS THE COLD FRONT APPROACHES FROM THE WEST. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...WINDS AND SEAS WILL BE CLOSE TO SCA THRESHOLDS AT THE START OF THE SHORT TERM PERIOD. SW WINDS UP TO 15 TO 20 KTS WILL PUSH SEAS UP CLOSE TO 5 TO 6 FT IN OUTER WATERS AND 3 TO 4 FT NEAR SHORE. WILL KEEP WITH SCA FOR NORTHERN 2 MARINE ZONES ONLY THROUGH THE DAY ON TUES. WINDS WILL VEER AROUND AS COLD FRONT APPROACHES LATE TUES INTO EARLY WED. THIS WEAKENING OFF SHORE FLOW AROUND 10 TO 15 KTS WILL ALLOW SEAS TO SUBSIDE DOWN TO 2 TO 4 FT THROUGH WED. WINDS AND SEAS WILL INCREASE AGAIN LATE WED INTO THURS AS GRADIENT TIGHTENS FIRST DUE TO MORE PRONOUNCED PIEDMONT TROUGH INLAND AND THEN DUE TO APPROACH OF COLD FRONT BY THURS. EXPECT SW WINDS BACK UP TO A SOLID 15 KTS OR SO BY THURS MORNING WITH SEAS UP AROUND 4 TO 5 FT IN OUTER WATERS. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 3 AM MONDAY...TIGHTENING GRADIENT FLOW AHEAD OF AN APPROACHING COLD FRONT WILL PRODUCE SW WINDS UP TO 15 TO 20 KTS. MAY EVEN SEA WINDS UP CLOSE TO 25 KTS JUST AHEAD OF COLD FRONT LATE THURS NIGHT INTO EARLY FRI. THIS WILL PUSH SEAS UP TO 6 TO 7 FT IN OUTER WATERS THURS NIGHT. BY FRIDAY...THE WINDS WILL VEER AROUND ABRUPTLY TO THE NW-N BEHIND COLD FRONT AND WILL DIMINISH DOWN TO 10 TO 15 KTS. SEAS WILL DROP BACK DOWN TO 2 TO 4 FT ON FRI. WINDS WILL CONTINUE TO VEER AROUND BECOMING MORE ON SHORE BUT LIGHT THROUGH THE WEEKEND AS HIGH PRESSURE SHIFTS DOWN FROM THE NORTH MOVING CLOSER OVERHEAD OVER THE WEEKEND. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 PM EDT TUESDAY FOR AMZ250-252. && $$ NEAR TERM...TRA SHORT TERM...RGZ LONG TERM...RGZ AVIATION...TRA/BJR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1000 AM CDT MON JUN 10 2013 .UPDATE... ISSUED AT 1000 AM CDT MON JUN 10 2013 FOG HAS DISSIPATED ACROSS THE JAMES RIVER VALLEY. AS A RESULT...THE DENSE FOG ADVISORY WAS CANCELLED. WATER VAPOR IMAGERY NICELY DEPICTS AN UPPER LOW OVER CENTRAL SASKATCHEWAN THIS MORNING. A JET STREAK ON THE SOUTHERN PERIPHERY OF THIS FEATURE IS NOSING ITS WAY ACROSS NORTH DAKOTA...AND HAS SPARKED A FEW THUNDERSTORMS ACROSS NORTHERN NORTH DAKOTA EAST OF HIGHWAY 83. THE LATEST SHORT RANGE MODEL GUIDANCE PROGS THIS ACTIVITY TO CONTINUE TO PUSH EAST OF THE CWA AS THE JET STREAK SHIFTS EAST OF THE REGION. OTHERWISE...UPDATED TO THE FORECAST TO ADJUST POPS BASED ON CURRENT RADAR OBS AND HRRR TRENDS. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT. UPDATE ISSUED AT 630 AM CDT MON JUN 10 2013 MAIN UPDATE WAS TO EXPAND THE COVERAGE OF SHOWERS AND THUNDERSTORMS THIS MORNING. STRONG UPPER LEVEL JET STREAK COMBINED WITH SURFACE LOW PRESSURE MOVING FROM WEST TO EAST ACROSS NORTH DAKOTA PROVIDING PLENTY OF LIFT FOR PRECIPITATION GIVEN RELATIVELY HIGH BOUNDARY LAYER MOISTURE IN PLACE. A FEW STRONGER STORMS POPPING UP...HOWEVER MUCAPE AT AROUND 100 J/KG IS LIMITING THE SEVERE POTENTIAL. A FEW MORE HUNDRED JOULES AND WOULD THINK SEVERE CRITERIA WOULD EASILY BE MET FOR SOME STORMS GIVEN THE FORCING IN PLACE. DENSE FOG ADVISORY SPOT ON...NO CHANGES NEEDED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 413 AM CDT MON JUN 10 2013 THE MAIN FORECAST CHALLENGE WILL BE DETERMINING THE CHANCES AND AREAL EXTENT OF EXPECTED SHOWERS AND THUNDERSTORMS FOR TODAY AND TONIGHT...AND THE DEVELOPING FOG IN THE JAMES RIVER VALLEY. CURRENTLY...A LOW PRESSURE CENTER WAS OVER EASTERN WYOMING WITH A TROUGH EXTENDING NORTHEASTWARD ACROSS WESTERN NORTH DAKOTA AND INTO SOUTHEASTERN SASKATCHEWAN. WEST OF THIS TROUGH WINDS WERE GENERALLY OUT OF THE NORTH. EAST OF THE TROUGH WINDS WERE SOUTHEASTERLY WITH PLENTY OF LOW LEVEL MOISTURE. A LARGE AREA OF FOG EXTENDED ACROSS MUCH OF IOWA AND MINNESOTA...AND HAS SPREAD INTO THE EASTERN DAKOTAS. DENSE FOG HAD DEVELOPED OVER THE SHEYENNE RIVER VALLEY AND HAS SPREAD INTO THE JAMES RIVER VALLEY. OAKES REPORTED 1/4 MILE VISIBILITY...AND JAMESTOWN WAS VARYING BETWEEN 3/4 AND 3 MILES. EXPECT THAT THE DENSE FOG WILL SPREAD NORTHWARD INTO JAMESTOWN...AND WILL ISSUE A DENSE FOG ADVISORY FOR FOSTER/STUTSMAN/LAMOURE/LOGAN COUNTIES - ALONG THE JAMES RIVER VALLEY - UNTIL 10 AM CDT. AT THE SURFACE...THE AFOREMENTIONED TROUGH OVER WESTERN NORTH DAKOTA EXTENDED BETWEEN TWO LOW PRESSURE SYSTEMS - ONE OVER CENTRAL SASKATCHEWAN AND THE OTHER OVER EASTERN WYOMING. AT UPPER LEVELS...A LARGE LOW WAS STACKED OVER THE SURFACE LOW IN SASKATCHEWAN WITH SEVERAL VORT ENERGY IMPULSES ROTATING AROUND THE LOW. THE UPPER FLOW ACROSS NORTH DAKOTA...ON THE SOUTHERN END OF THE UPPER LOW`S INFLUENCE...WAS WEST-TO-EAST AND ENERGY IMPULSES ARE FORECAST TO CONTINUE MOVING EASTWARD ACROSS NORTH DAKOTA TODAY. THE SURFACE TROUGH IS FORECAST TO MOVE EASTWARD ACROSS THE DAKOTAS TODAY AND REACH THE RED RIVER VALLEY LATER TONIGHT. THIS BOUNDARY WILL BE THE FOCUS OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA TODAY. SHOWERS AND ISOLATED THUNDERSTORMS THAT DEVELOPED SUNDAY EVENING CONTINUED THIS MORNING...WITH THE BEST INSTABILITY OVER THE WYOMING/SOUTH DAKOTA BORDER NEAR THE SURFACE LOW. HOWEVER THIS MORNING AN INSTABILITY AXIS (OF HIGHER MID LEVEL LAPSE RATES AND ELEVATED CAPE) EXTENDED FROM THE WY/SD BORDER ACROSS WESTERN NORTH DAKOTA. THIS COINCIDES WITH THE SURFACE TROUGH AND CONFIDENT THAT THE BEST CHANCES FOR CONVECTION TODAY WILL BE ALONG THE TROUGH. THE EASTWARD-MOVING UPPER LEVEL IMPULSES WILL ENHANCE THE CONVECTION AND HELP MOVE THE SHOWERS EASTWARD. TONIGHT...THE MODELS INDICATE THE CANADIAN LOW BEGINNING TO LIFT NORTHEASTWARD...AND KEEPING THE ASSOCIATED UPPER IMPULSES NORTH OF THE CANADIAN BORDER. HOWEVER...A DEVELOPING UPPER LEVEL TROUGH OVER THE ROCKIES DAYTIME MONDAY WILL APPROACH THE DAKOTAS TONIGHT AND BRING INCREASING CHANCES OF THUNDERSTORMS TONIGHT IN SOUTHWESTERN NORTH DAKOTA. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 413 AM CDT MON JUN 10 2013 MODELS OVERALL IN DECENT AGREEMENT REGARDING THE GENERAL SYNOPTIC PATTERN FOR THE LONG TERM FORECAST PERIOD. LARGER DIFFERENCES IN THE DETAILS FOR THE CURRENT 00Z MODEL SUITE COMPARED TO YESTERDAY. FORECAST HIGHLIGHTS IN THE EXTENDED PERIOD WILL BE CHANCES FOR SHOWERS/THUNDERSTORMS THROUGH THE WORK WEEK INTO NEXT WEEKEND. WILL SEE SOME PERIODS OF GREATER PRECIPITATION CHANCES AND COVERAGE...TUESDAY/TUESDAY NIGHT/WED MORNING AND AGAIN THURSDAY NIGHT THROUGH FRIDAY AFTERNOON/EVENING. UPPER LEVEL RIDGE BUILDS EAST ACROSS THE SOUTHERN PLAINS MONDAY NIGHT WITH LINGERING UPPER LEVEL LOW PRESSURE OVER SOUTH CENTRAL CANADA. MID LEVEL LOW PRESSURE CURRENTLY OFF THE SOUTHERN CALIFORNIA COAST IS STILL FORECAST TO EJECT NORTHEAST ACROSS THE ROCKIES AND INTO THE DAKOTAS...NOW ARRIVING TUESDAY NIGHT/EARLY WEDNESDAY. EARLIER MODEL RUNS HAD THIS FEATURE ARRIVING 6-12 HOURS FASTER. A FEW CHANGES TO DISCUSS FOR TUESDAY MORNING/AFTERNOON. THE LAST TWO RUNS OF THE ECMWF PAINT A BAND OF QPF ACROSS NORTHWEST NORTH DAKOTA WITH LIGHTER QPF OVER THE REST OF THE CWA. WHILE THE GFS IS DRY...THE NAM ALSO IS INDICATING PRECIPITATION. DISCOUNTED THE GFS FOR THIS PARTICULAR PERIOD AS IT APPEARS THERE WILL BE ENOUGH OVERRUNNING FLOW AND FORCING ALOFT IN THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET TO WARRANT MENTIONING PRECIPITATION. MUCH DEPENDS ON HOW FAR SOUTH SURFACE HIGH PRESSURE EXTENDS INTO THE REGION AND HOW FAR WEST AS WELL. THE GFS HAS A SURFACE RIDGE EXTENDING OVER ALL BUT THE SOUTHWEST...WHILE ECMWF IS A TAD MORE NORTH. THE SFC HIGH WILL LIMIT THUNDERSTORM CHANCES TUESDAY/TUESDAY NIGHT TO THE FAR SOUTH WITH LITTLE IF ANY INSTABILITY NORTH OF THE SD/ND BORDER COUNTIES. UPPER LEVEL RIDGE REBUILDS ACROSS THE NORTHERN PLAINS WEDNESDAY DAYTIME...WITH THE RIDGE AXIS PUSHING INTO THE CENTRAL DAKOTAS WEDNESDAY NIGHT/THURSDAY AHEAD OF A LONG WAVE TROUGH DEVELOPING OVER THE WEST COAST. SHOWERS ARE EXPECTED TO LINGER MAINLY SOUTH WED MORNING..WITH ISOLATED CONVECTION POSSIBLE WED AFTERNOON. MODELS HAVE DIVERGED FROM THEIR EARLIER AGREEMENT WITH SOUTHWEST FLOW ALOFT DEVELOPING OVER MY WEST. THE ECMWF HAS SLOWED DOWN WITH THE EASTWARD PROGRESSION OF THE RIDGE AXIS...WITH SOUTHWEST FLOW DEVELOPING NOT UNTIL THURSDAY DAYTIME. THE GFS STILL MAINTAINS FLOW ALOFT TRANSITIONING TO SOUTHWEST WED NIGHT. SCALED BACK POPS CENTRAL WED NIGHT BUT KEPT A MENTION OF NOCTURNAL THUNDERSTORMS WEST. WEST COAST TROUGH LIFTS INTO THE WYOMING/MONTANA ROCKIES BY 12Z FRIDAY...THEN EAST-NORTHEAST THROUGH THE NORTHERN PLAINS FRIDAY-FRIDAY NIGHT. ASSOCIATED SURFACE TROUGH IS STILL FORECAST TO MOVE INTO WESTERN NORTH DAKOTA 6-12Z FRIDAY MORNING...AND INTO EASTERN NORTH DAKOTA 00-06Z FRIDAY EVENING. THIS SUGGESTS HIGH CHANCES AND EXTENSIVE COVERAGE OF THUNDERSTORMS WEST LATE THURSDAY NIGHT DEVELOPING EAST FRIDAY MORNING/AFTERNOON WITH DECREASING CHANCES/COVERAGE FROM WEST TO EAST FRIDAY AFTERNOON INTO FRIDAY EVENING BEHIND THE SFC TROUGH AND UPPER LEVEL WAVE. WILL NEED TO MONITOR FOR STRONG TO SEVERE POSSIBILITY THIS PERIOD GIVEN THE FORCING AND INSTABILITY PARAMETERS. THE ALL-BLEND MODEL CONSENSUS MAINTAINS A SLIGHT CHANCE OF PRECIPITATION SATURDAY AND SUNDAY...BUT THE WEEKEND DOES NOT APPEAR TO BE A WASH-OUT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) AT 6 AM CDT...A WEAK FRONTAL BOUNDARY EXTENDED FROM A LOW IN WYOMING ACROSS WESTERN NORTH DAKOTA AND INTO SASKATCHEWAN. THIS FEATURE...ALONG WITH UPPER LEVEL ENERGY IMPULSES MOVING FROM WEST TO EAST ACROSS THE STATE WILL KEEP SHOWERS AND ISOLATED THUNDER AT KDIK/KMOT/KBIS/KJMS TODAY. THE THREAT OF THUNDER OR RAIN SHOWERS IS TOO LOW TO MENTION AT KISN. OTHERWISE MAINLY VFR CONDITIONS ARE EXPECTED TODAY. TONIGHT MVFR AT KDIK AND KJMS MAINLY AFT 06Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TM SHORT TERM...JV LONG TERM...NH AVIATION...JV
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
700 AM CDT MON JUN 10 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 346 AM CDT MON JUN 10 2013 CLEAR SKIES/LIGHT WINDS AND RESIDUAL BOUNDARY LAYER MOISTURE FROM RECENT RAINS ALLOWING DENSE FOG TO DEVELOP IN WESTERN/CENTRAL PARTS OF THE CWA EARLY THIS MORNING. HRRR HAS LATCHED ONTO EXPANSION OF THE LOWEST VISIBILITIES WHICH HAS OCCURRED OVER THE PAST HOUR OR SO...AND IT SHOWS POTENTIAL FOR DENSE FOG PERSISTING IN THE SURFACE RIDGE AXIS THROUGH ABOUT 13-14Z WITH RAPID IMPROVEMENT THEREAFTER. ISSUED DENSE FOG ADVISORY DUE TO EXPECTED PERSISTENCE...THOUGH MAY STILL BE A BIT PATCHY IN SPOTS...ESPECIALLY THE FAR WEST WHERE THE WIND MAY PICK UP A BIT AS THE RIDGE SHIFTS EAST. STRATUS AND A BIT MORE WIND EAST OF THE RIDGE AXIS HAS HELPED TO HOLD VISIBILITY UP ACROSS NORTHWEST IOWA AND PARTS OF SOUTHWEST MN THUS FAR...SO DID NOT INCLUDE THEM IN THE ADVISORY AT THIS TIME...THOUGH WILL WATCH FOR DOWNWARD TREND SHOULD THE STRATUS CLEAR. SEEING SOME ACCAS STREAMING TOWARD FAR WESTERN COUNTIES EARLY THIS MORNING AS WELL. SOUTHERN EDGE HAS SHOWN TENDENCY TO DISSIPATE AS IT SHIFTS EAST... AND 06Z NAM INDICATES THIS TREND AS WELL...KEEPING BULK OF HIGHER MID LEVEL MOISTURE NORTH OF OUR CWA THROUGH THE MORNING. DID BRING IN A LITTLE HIGHER SKY COVER TO OUR NORTHWEST EARLY...BUT THINK MOST OF THE DAY SHOULD SEE FAIR AMOUNT OF SUNSHINE. THUS AFTER THE FOG BURNS OFF...EXPECT TEMPERATURES TO REBOUND NICELY...THOUGH PERHAPS A BIT MORE SLOWLY IN THE EAST WHERE STRATUS MAY LINGER INTO THE MID TO LATER MORNING HOURS. WITH 925MB TEMPERATURES FORECAST TO RISE INTO THE 20S C BY 11/00Z...HIGHS FROM THE UPPER 70S EAST TO THE MID-UPPER 80S SOUTHWEST LOOK GOOD. MID LEVEL CLOUDS WILL BE ON THE INCREASE MONDAY NIGHT AS ATMOSPHERE ABOVE 600 MB SATURATE IN RESPONSE TO INCREASE IN THETAE ADVECTION. WHILE SHORTWAVE IS EXPECTED TO MOVE ACROSS THE FORECAST AREA...APPEARS AS THOUGH ATMOSPHERE WILL REMAIN EFFECTIVELY CAPPED LIMITING THUNDERSTORM POTENTIAL TO FAR WESTERN PORTIONS OF CWA IN CENTRAL SOUTH DAKOTA. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM CDT MON JUN 10 2013 THE OUTSIDE CHANCE OF AN ELEVATED STORMS WILL CONTINUE THROUGH TUESDAY MORNING...BUT EXPECT CHANCES TO DWINDLE THROUGHOUT THE DAY ON TUESDAY. FORECAST AREA REMAINS IN EASTERLY FLOW THROUGHOUT THE DAY ON TUESDAY AS WARM FRONT LIFTS NORTH TOWARDS THE CWA. TOUGH CALL ON CONVECTION CHANCES TUESDAY NIGHT WITH STRONG MID LEVEL CAP PRESENT. MODELS HIND THAT CAP MAY TRY TO WEAKEN...AND THE BEST CHANCE FOR THUNDERSTORMS REMAINS ACROSS THE NORTHERN FRINGE OF THE FORECAST AREA. IF STORMS ARE ABLE TO DEVELOP...THEY WOULD LIKELY QUICKLY BECOME SEVERE PRODUCING SEVERE HAIL WITH STRONG MID LEVEL LAPSE RATES. HAVE LEFT LINGERING POPS INTO WEDNESDAY...THOUGH THERE IS REALLY A LACK OF ANY LARGE SCALE FOCUSING MECHANISM WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NORTH. AS SUCH...JUST HAVE A GENERAL 20-40 CHANCE WHICH WILL BE VERY DEPENDENT ON WHAT HAPPENS TUESDAY NIGHT. THURSDAY INTO THE BETTER PORTION OF FRIDAY SHOULD BE RELATIVELY DRY. THE EXCEPTION TO THIS WOULD BE LATE ON THURSDAY NIGHT AS WARM AIR ADVECTION INCREASES UNDER SOUTHERLY FLOW AND COULD SEE ACCAS SHOWERS. POTENTIAL FOR DEEP CONVECTION FRIDAY NIGHT CONTINUES TO INCREASE AS UPPER LEVEL LOW PRESSURE SYSTEM LIFTS NORTHEAST INTO CENTRAL CANADA AND TRAILING COLD FRONT MOVES ACROSS THE FORECAST AREA. WHAT CONTINUES TO BE IMPRESSIVE ABOUT THIS SET UP ARE THE VERY STEEP LAPSE RATE FROM 700-400 MB AND SPEED SHEAR ALOFT INDICATING THE POTENTIAL FOR VERY LARGE HAIL IF THUNDERSTORMS ARE ABLE TO DEVELOP. THE UNSETTLED PATTERN CONTINUES INTO THE WEEKEND AS UPPER LEVEL LOW RE-ESTABLISHES ITSELF OFF THE PACIFIC NW COAST. PIECES OF ENERGY PERIODICALLY BREAK OFF THE UPPER LEVEL LOW EJECTING INTO THE PLAINS. AT THIS POINT...IT CONTINUES TO BE DIFFICULT TO PINPOINT PRECISE TIMING OF DEEP CONVECTION...BUT HAVE STARTED TO TWEAK DAYTIME POPS DOWN AND NOCTURNAL POPS UP TO HELP ACCOUNT FOR TYPICAL DIURNAL PATTERN THIS TIME OF YEAR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 700 AM CDT MON JUN 10 2013 LIFR CONDITIONS FAIRLY WIDESPREAD ACROSS THE AREA AT THE START OF THE PERIOD...EITHER WITH SUB 1SM VISIBILITY IN FG OR CEILINGS AT OR BELOW 400FT AGL IN STRATUS. EXPECT CONDITIONS TO IMPROVE AFTER 14Z...THOUGH CEILINGS NEAR/EAST OF I-29 CORRIDOR MAY BE SLOWER TO IMPROVE THAN VISIBILITY. VFR CONDITIONS EXPECTED ACROSS THE FORECAST AREA BY 17Z- 18Z. REMOTE CHANCE OF ISOLATED HIGH BASED SHRA/TSRA WEST OF I-29 LATE IN THE FORECAST PERIOD...BUT CHANCE TOO SMALL TO MENTION IN KHON TAF. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR SDZ038>040- 053>056-059>062-065>071. MN...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR MNZ071-072- 080-097-098. IA...NONE. NE...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ013-014. && $$ SHORT TERM...JH LONG TERM... AVIATION...JH
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1058 AM CDT MON JUN 10 2013 .UPDATE... MORNING FORECAST UPDATE. && .DISCUSSION... MAIN ISSUE TODAY MAY BE CONVECTION AGAIN BUT A LOT MORE ISOLATED COMPARED TO YESTERDAY. WATER VAPOR IMAGERY SHOWS THAT YESTERDAY`S TROUGH AXIS HAS LEFT BEHIND A WEAK CLOSED LOW OVER S TX/LOWER TX COAST. MAY JUST KEEP ENVIRONMENT FAVORABLE FOR CONVECTION WITH MORE DAYTIME HEATING AND SEA BREEZE BOUNDARY DEVELOPING. THE 12/13Z HRRR RUNS HAVE CONVECTION DEVELOPING 17-18Z AND ENDING BY 22Z. FORECAST HAS 20/30 POPS AND THINK THIS MAY BE ON TRACK. COVERAGE MAY NOT BE AS MUCH TO NEED 30 POPS BUT LOOKS REASONABLE. OVERALL FORECAST LOOKS ON TRACK AND WILL NOT ISSUE AN UPDATE. 39 && .PREV DISCUSSION... /ISSUED 635 AM CDT MON JUN 10 2013/ DISCUSSION... SEE AVIATION FOR 12Z TAF ISSUANCE. AVIATION... CURRENTLY HAVE LIFR AND IFR CONDITIONS AT RURAL SITES DUE TO MORNING FOG. URBAN SITES HAVE BEEN SPARED MOST OF THE FOGGY CONDITIONS. FOG SHOULD QUICKLY BURN OFF THIS MORNING PRODUCING VFR CONDITIONS ACROSS THE AREA. THERE WILL BE ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON AS THE UPPER LEVEL WEAKNESS REMAINS IN CLOSE PROXIMITY TO THE AREA. COVERAGE SHOULD BE MORE LIMITED TODAY AS PRECIPITABLE WATER VALUES HAVE ALREADY COME DOWN SINCE YESTERDAY. VALUES OF AROUND 1.50" THOUGH STILL SHOULD SUPPORT RAIN. SOUNDINGS REVEAL MODEST MOISTURE AND INSTABILITY VALUES WITH CONVECTIVE TEMPERATURES AROUND 90 DEGREES WHICH APPEAR TO BE VERY ACHIEVABLE THIS AFTERNOON. WHERE MOISTURE IS MORE LIMITED TOWARDS THE NORTH MIGHT HAVE A HARD TIME GETTING RAIN BUT AT KIAH AND SOUTHWARDS STILL SHOULD HAVE ENOUGH MOISTURE TO WORK WITH. 23 PREV DISCUSSION... /ISSUED 341 AM CDT MON JUN 10 2013/ DISCUSSION... AN ELONGATED MID/UPPER LEVEL SHEAR AXIS IS ALONG THE UPPER TEXAS COAST EARLY THIS MORNING. PER HIGH RESOLUTION MODELS...EXPECT TO SEE INCREASING SHOWER/THUNDERSTORM DEVELOPMENT ACROSS THE GULF WATERS BEFORE SUNRISE... DEVELOPMENT IN/NEAR THE COASTAL COUNTIES THIS MORNING...AND FURTHER INLAND THIS AFTERNOON. EXPECT A LOT LESS INLAND COVERAGE THAN THE AREA SAW YESTERDAY. AS THIS WEEK PROGRESSES...STILL EXPECT TO SEE A DRYING AND WARMING TREND FOR A MAJORITY OF THE AREA AS UPPER LEVEL RIDGING BUILDS ACROSS THE AREA (SPOTS AROUND THE MATAGORDA BAY AREA MIGHT END UP BEING THE BEING THE LAST TO DRY OUT). STILL CARRYING MID TO UPPER 90S FOR HIGHS FOR MUCH OF INLAND SOUTHEAST TEXAS BEGINNING ON WEDNESDAY AND CONTINUE THROUGH THE END OF THE WEEK AND ON INTO THE WEEKEND. 42 MARINE... THE UPPER LEVEL DISTURBANCE THAT GAVE US RAINFALL YESTERDAY WILL CONTINUE TO RETROGRADE TO THE WEST TODAY WHILE THE MAIN TROUGH AXIS MOVES OFF TOWARDS THE EAST. WATERS COULD SEE SOME MORE SHOWERS AND THUNDERSTORMS TODAY AS POCKETS OF VORTICITY MOVE AROUND THE DISTURBANCE. LIGHT TO MODERATE ONSHORE WINDS WITH MOSTLY LOW SEAS CAN BE EXPECTED THROUGH THE WEEK. 23 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 94 74 95 74 95 / 10 10 10 10 10 HOUSTON (IAH) 93 74 94 75 94 / 30 10 20 10 10 GALVESTON (GLS) 87 79 88 80 88 / 30 10 20 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...39
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
636 AM CDT MON JUN 10 2013 UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 424 AM CDT MON JUN 10 2013 WV IMAGERY AND RAP ANALYSIS SHOWED AN UPPER LOW WEAKENING AS IT MOVED ESE INTO CENTRAL IL. SCATTERED SHOWERS ASSOCIATED WITH ITS DEFORMATION ZONE WERE ATTEMPTING TO WRAP BACK INTO OUR FAR SE COUNTIES...BUT WERE DISSIPATING. STRONG ZONAL FLOW ALOFT WAS IN PLACE FROM THE PACIFIC NW THROUGH MINNESOTA...WITH A WELL-DEFINED S/W TROF AND 110 KT JET STREAK MOVG ALONG THE NORTH DAKOTA/CANADIAN BORDER. THIS ENERGY APPEARED POISED TO CLIP NORTHERN WI LATER TODAY. CLOUDS HAD SCATTERED OUT OVER MUCH OF GRB EARLY THIS MORNING...AND PATCHY FOG WAS DEVELOPING. PATCHY FOG SHOULD DISSIPATE QUICKLY BY MID-MORNING. SHOWERS ASSOCIATED WITH THE DEPARTING UPPER SYSTEM ARE NOT EXPECTED TO MAKE IT INTO OUR FAR SE COUNTIES EARLY TODAY...SO WILL NOT MENTION. S/W TROF AND JET STREAK MOVG RAPIDLY THROUGH ND AND NW MN SHOULD MOVE INTO N WI LATE THIS MORNING AND AFTERNOON...AND COMBINE WITH DAYTIME HEATING AND WEAK LOW-LEVEL CONVERGENCE TO PRODUCE SCT SHOWERS OVER MUCH OF THE FA. THE SHOWERS ARE EXPECTED TO MOST NUMEROUS OVER NC/FAR NE WI...WHERE FORCING AND INSTABILITY (CAPE 300-400 J/KG) IS EXPECTED TO BE GREATEST. HAVE INCLUDED A MENTION OF ISOLD TSTMS OVER THE FAR NORTH. CONSIDERED GOING WITH LIKELY POPS OVER NORTHERN WI...BUT OPTED FOR HIGH CHANCE POPS INSTEAD...AS THE 00Z ECMWF CAME IN WITH MUCH LESS QPF THAN ITS PREVIOUS RUN. MIXING THROUGH 875-850 MB SUPPORTS HIGH TEMPS IN THE MIDDLE 70S AWAY FROM LAKE MICHIGAN. GENERALLY DRY CONDITIONS ARE EXPECTED ACROSS THE REGION TONIGHT... WITH LIGHT WINDS AND PARTLY CLOUDY SKIES LEADING TO SOME FOG DEVELOPMENT OVERNIGHT. EXPECT A MILD NIGHT...WITH MIN TEMPS IN THE 50S. ON TUESDAY...ADDITIONAL SHORT-WAVE AND JET ENERGY WILL SKIM BY TO OUR NORTH AS A WEAK/SHALLOW COLD FRONT DROPS INTO THE REGION. HAVE CONTINUED WITH LOW POPS OVER NORTHERN WI...BUT POPS MAY NEED TO BE EXPANDED OVER MORE OF THE FORECAST AREA WITH SUBSEQUENT FCSTS. MIXING THROUGH 850-800 MB SUPPORTS A WARM DAY...WITH HIGHS IN THE LOWER 80S. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 424 AM CDT MON JUN 10 2013 MODEL GUIDANCE CONTINUED TO FOCUS ON A MORE SOUTHERLY SOLUTION FOR AN APPROACHING SHORT WAVE...SURFACE LOW PRESSURE SYSTEM AND ASSOCIATED FRONTAL BOUNDARY FOR TUESDAY NIGHT AND WEDNESDAY. HAVE GONE WITH A CHANCE OF SHOWERS AND THUNDERSTORMS FOR PARTS OF CENTRAL AND EAST CENTRAL WISCONSIN AND LEFT THE NORTH DRY BECAUSE OF THIS. SURFACE HIGH PRESSURE AND AN UPPER LEVEL RIDGE ACROSS THE CENTRAL CONUS SHOULD KEEP THURSDAY AND FRIDAY DRY...BEFORE THE NEXT SHORT WAVE AND AN APPROACHING COLD FRONT BRING A CHANCE OF SHOWERS AND THUNDERSTORMS BACK TO THE AREA FOR FRIDAY NIGHT AND SATURDAY. PRECIPITATION MAY LINGER INTO SUNDAY SO HAVE LEFT SOME CHANCE POPS IN FOR SATURDAY NIGHT AND SUNDAY AS WELL. TEMPERATURES SHOULD BE WITHIN A FEW DEGREES OF NORMAL FOR MOST OF THE FORECAST PERIOD. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 632 AM CDT MON JUN 10 2013 AREAS OF IFR/LIFR FOG IN NC/C WI WILL DISSIPATE BY 13Z-14Z...FOLLOWED BY MAINLY VFR CONDITIONS FOR THE REST OF TODAY AND THIS EVG. SCT SHOWERS WILL DEVELOP THIS AFTERNOON...ESPECIALLY OVER NC/FAR NE WI...WHERE ISOLD TSTMS ARE ALSO EXPECTED. LIGHT WINDS...PARTLY CLOUDY SKIES AND LOW-LEVEL MOISTURE SHOULD RESULT IN FOG DEVELOPMENT AGAIN LATE TONIGHT...WITH VSBYS DROPPING TO IFR/LIFR IN SOME AREAS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....KIECKBUSCH LONG TERM......MG AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS ALBANY NY
405 PM EDT MON JUN 10 2013 .SYNOPSIS... A LOW PRESSURE SYSTEM AND ITS ASSOCIATED FRONTAL BOUNDARIES WILL APPROACH FROM THE OHIO VALLEY AND GREAT LAKES...AND MOVE ACROSS OUR REGION THROUGH TUESDAY. THIS SYSTEM WILL BRING A WIDESPREAD SOAKING RAINFALL. THE RAIN WILL BE HEAVY AT TIMES...ALONG WITH POSSIBLE THUNDERSTORMS. DRIER WEATHER IS EXPECTED WEDNESDAY AND WEDNESDAY NIGHT WITH WEAK HIGH PRESSURE BUILDING IN. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... THROUGH TONIGHT...EXPECT UNSETTLED WEATHER WITH RAINFALL HEAVY AT TIMES ESPECIALLY THIS EVENING. LOW PRESSURE OVER THE OHIO VALLEY AND CENTRAL GREAT LAKES LATE THIS AFTERNOON WILL LIFT AND OCCLUDED FRONT IN OUR DIRECTION TONIGHT. THE TRIPLE POINT WITH THE WARM FRONT AND TRAILING COLD FRONT IS EXPECTED TO PASS ACROSS THE EXTREME SOUTHEAST CORNER OF OUR FA LATE TONIGHT. THIS SCENARIO WILL RESULT IN SOME LOCALLY HEAVY RAINFALL ESPECIALLY THROUGH SHORTLY AFTER MIDNIGHT. PWATS THIS EVENING RISE TO BETWEEN 1.75 AND 2 INCHES ALONG WITH STRONG LOW LEVEL MOISTURE CONVERGENCE. RAINFALL AMOUNTS OF AN INCH TO LOCALLY OVER 2 INCHES CAN BE EXPECTED THROUGH TONIGHT. WILL KEEP ISOLATED THUNDER IN THE FORECAST AS WELL EVEN THOUGH SHOWALTER INDICES ONLY BRIEFLY NEAR ZERO AND SBCAPES ONLY A FEW HUNDRED J/KG. EXPECT OVERNIGHT LOWS TO BE IN THE MID 50S TO MID 60S. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... ON TUESDAY...IT DOES NOT APPEAR THAT THERE WILL BE A GREAT DEAL OF SURFACE HEATING AS EXTENSIVE CLOUD COVER IS EXPECTED DURING MUCH OF THIS PERIOD. SBCAPES TUESDAY AFTERNOON BTWN 400 AND 800 J/KG. BETTER CHANCE FOR ELEVATED CONVECTION AS SECONDARY TROUGH ASSOCIATED WITH ANOTHER WAVE OF LOW PRESSURE MOVING ACRS NRN NEW YORK PASSES THROUGH OUR REGION. EXPECT MORE SHOWERS ALONG WITH ISOLATED THUNDERSTORMS AND PCPN GENERALLY AN ADDITIONAL QUARTER TO HALF INCH IN MOST AREAS WITH ISOLATED AMOUNTS UP TO AN INCH. EXPECT HIGHS ON TUESDAY TO BE IN THE 60S TO MID 70S. MORE RAIN IS EXPECTED TUESDAY NIGHT AS A THIRD TROUGH OF LOW PRESSURE SWINGS THROUGH THE FA WITH THE RAIN EXPECTED TO TAPER OFF LATE AT NIGHT. EXPECT LOWS TUESDAY NIGHT IN THE UPPER 50S TO LOWER 60S. ON WEDNESDAY EXPECT A BREEZY DAY WITH STILL THE POSSIBILITY OF SCATTERED SHOWERS ESPECIALLY ACRS NRN AREAS AS A STRONG VORT AXIS CROSSES FA SWINGING ARND THE BASE OF THE H5 TROF. HIGHS ON WEDNESDAY ARE EXPECTED TO BE IN THE UPPER 60S TO UPPER 70S WITH READINGS ARND 80 NEAR KPOU. WEDNESDAY NIGHT AND THURSDAY THE FORECAST WILL HINGE ON HOW FAR NORTH THE RAINFALL SHIELD ASSOCIATED WITH A SYSTEM PASSING TO OUR SOUTHEAST GETS TO OUR AREA. AT THIS TIME WILL FORECAST CHANCE POPS ACRS THE SRN HALF OF THE FA. EXPECT LOWS WEDNESDAY NIGHT IN THE UPPER 40S TO LOWER 50S WITH HIGHS ON THURSDAY IN THE UPPER 60S TO MID 70S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... THE LONG TERM STARTS OUT A BIT UNSETTLED...BUT THINGS IMPROVE FOR THE UPCOMING WEEKEND. THE GFS/ECMWF/GEFS MEAN/CANADIAN GGEM/HPC GUIDANCE ALL INDICATE A CYCLONE WILL MOVE FROM THE OHIO VALLEY INTO THE MID ATLANTIC REGION ON THU-THU NIGHT. THE SFC CYCLONE IS ASSOCIATED WITH A PROGRESSIVE POSITIVELY TILTED LONG WAVE TROUGH. AN INVERTED SFC TROUGH EXTENDING N/NE OF THE SFC CYCLONE WILL PRODUCE SOME SHOWERS AS FAR NORTH AS THE INTERSTATE 90 CORRIDOR THU PM. THERE WILL LIKELY BE A SHARP CUT-OFF IN THE OVER RUNNING RAINFALL. THE NRN ZONES MAY STAY DRY. FOR NOW...SLIGHT CHC POPS ARE IN THE FORECAST FOR THU NIGHT NORTH OF THE MID HUDSON VALLEY...SE CATSKILLS...AND NW CT. CHC POPS ARE KEPT FURTHER SOUTH AND EAST. THE ECMWF TRIES TO KEEP THE STEADY SHOWERS GOING THU NIGHT. THE SYSTEM LOOKS PROGRESSIVE ENOUGH TO NOT PLACE HIGHER POPS AT THIS TIME. LOWS WILL BE IN THE M40S TO NEAR 50F OVER THE HIGHER TERRAIN...AND LOWER TO M50S IN THE VALLEYS AND OVER TH HILLS. FRI-FRI NIGHT...A COLD FRONT DROPS SOUTH AND EAST FROM THE ST LAWRENCE RIVER VALLEY. THE GFS HAS SBCAPES OF 250-500 J/KG WITH TOTAL TOTALS OF AROUND 50. THE 850-500 HPA LAPSE RATES APPROACH 6.5 C/KM. SOME SHOWERS WITH ISOLD THUNDERSTORMS WILL BE POSSIBLE WITH THE FRONTAL PASSAGE. THE BETTER UPPER LEVEL DYNAMICS ARE DISPLACED TO THE NORTH...AND THE LOW-LEVEL MOISTURE IS LIMITED WITH SFC DEWPTS IN THE M40S TO M50S. H850 TEMPS WILL BE AROUND +10C...SO MAX TEMPS WILL BE SEASONABLE IN 70-75F RANGE IN THE VALLEYS AND NW CT...AND MID AND U60S OVER THE MTNS. WEAK COLD ADVECTION WILL OCCUR IN THE WAKE OF THE FRONT WITH HIGH PRESSURE BUILDING IN FROM SRN ONTARIO AND THE GREAT LAKES REGION. H850 TEMPS FALL TO +6C TO +9C. LOWS WILL RANGE FROM THE M40S TO M50S OVER THE FCST AREA. SATURDAY-SUNDAY...A LARGE DOME OF SFC HIGH PRESSURE WILL BE IN CONTROL OVER THE NORTHEAST AND THE MID ATLANTIC REGION. THE HIGH WILL RIDGE IN FROM THE CAROLINAS WITH A RETURN FLOW OF MILDER AIR. THE REGION WILL ENJOY PLENTY OF SUNSHINE WITH NEAR NORMAL TEMPS ON SAT...AND SLIGHTLY ABOVE NORMAL TEMPS FOR SUNDAY. SUNDAY NIGHT INTO MONDAY...A QUICK MOVING LOW PRESSURE SYSTEM WITH ITS ASSOCIATED FRONTAL BOUNDARIES WILL APPROACH FROM THE GREAT LAKES REGION IN THE NEAR ZONAL FLOW ALOFT. THE BEST CHC OF SHOWERS LOOKS LIKE MONDAY BASED ON THE CONSENSUS FROM THE MEDIUM RANGE GUIDANCE. THERE COULD BE SOME THUNDERSTORMS TOO...BUT BASED ON THE TIMING OF THE DISTURBANCE THEY HAVE NOT BEEN ADDED TO GRIDDED FCST YET. OVERALL...TEMPS WILL BE NEAR NORMAL WITH PCPN SLIGHT BELOW NORMAL FOR THE STRETCH. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... A STEADY RAIN HAS DEVELOPED ACROSS EASTERN NY AND WESTERN NEW ENGLAND AHEAD OF AN APPROACHING WARM FRONT. MOST OF THE RAINFALL HAS BEEN RATHER LIGHT SO FAR...WHICH HAS KEPT FLYING CONDITIONS GENERALLY VFR. BASED ON UPSTREAM OBS AND THE 3KM HRRR MODEL...AS THE AFTERNOON GOES ON...FLYING CONDITIONS WILL GRADUALLY DECREASE TO MVFR. THIS WILL BE DUE TO THE RAIN PICKING UP IN INTENSITY AND ALLOWING VSBYS TO DROP...ESP FOR THE SOUTHERN TERMINALS OF KPSF/KPOU. IT MAY TAKE UNTIL AFTER 00Z UNTIL KALB/KGFL SEE IFR CONDITIONS. A MODERATE STEADY RAIN IS EXPECTED AT ALL TERMINALS FOR THE LATE EVENING INTO THE FIRST HALF OF THE OVERNIGHT. THIS RAINFALL...ALONG WITH A PERSISTENT SOUTHERLY FLOW...SHOULD ALLOW FOR IFR CONDITIONS AT ALL SITES. LATE TONIGHT...THE STEADY RAIN WILL TAPER OFF...ALLOWING FOR IMPROVEMENT IN THE VSBYS...ALTHOUGH THERE WILL BE PLENTY OF LINGERING LOW LEVEL MOISTURE WHICH WILL KEEP SOME LOW STRATUS CLOUDS AROUND. BY THE MID MORNING HOURS ON TUESDAY...MOST OF THESE LOW CLOUDS SHOULD START TO BREAK UP...ALTHOUGH THERE STILL MAY BE SOME LINGERING SHOWERS AROUND. SFC WINDS ARE NEARLY CALM OR LIGHT OUT OF THE E-SE EARLY THIS AFTN. EVENTUALLY BY LATE IN THE DAY...WINDS WILL BE OUT OF THE SOUTH AROUND 5-10 KTS. WINDS WILL SWITCH TO A W-SW DIRECTION ON TUESDAY AT SIMILAR SPEEDS. OUTLOOK... TUE PM-TUE NIGHT...VFR/MVFR. CHC -SHRA/TSRA WED...VFR...NO SIG WX. THU...VFR/MVFR. CHC -SHRA/TSRA AT KPOU. FRI...VFR. NO SIG WX. && .FIRE WEATHER... WET WEATHER IS EXPECTED THROUGH TUESDAY NIGHT. RAINFALL AMOUNTS ARE EXPECTED TO RANGE FROM 1 TO 3 INCHES WITH THE HEAVIEST RAINFALL EXPECTED THIS EVENING. && .HYDROLOGY... MODERATE TO HEAVY RAIN IS EXPECTED WITH THE CURRENT RAINFALL EVENT THROUGH TUESDAY NIGHT. THROUGH TUESDAY NIGHT A LOW PRESSURE SYSTEM WITH A OCCLUDED FRONT IS EXPECTED TO CROSS OUR REGION. AT THIS TIME RAINFALL AMOUNTS LOOK TO BE QUITE HEAVY WITH 1 TO 3 INCHES OF RAIN EXPECTED WITH LOCALIZED HIGHER AMOUNTS. THE HEAVIEST RAIN APPEARS AS THOUGH IT WILL BE ACROSS SOUTHERN VERMONT...THE NORTHERN TACONICS AND THE BERKSHIRES WITH A SECONDARY AXIS OF HEAVY PCPN ACRS THE ERN CATSKILLS. THE HOUSATONIC BASIN WILL ALSO BE IMPACTED WITH THE POTENTIAL FOR MINOR FLOODING ALONG THE CONNECTICUT SECTION OF THE RIVER. A FLOOD WATCH REMAINS IN EFFECT FOR BERKSHIRE AND LITCHFIELD COUNTIES. AFTER A BRIEF LULL IN THE PRECIPITATION DURING MID WEEK...MORE RAIN IS POSSIBLE BY THURSDAY AS A LOW PRESSURE SYSTEM PASSING SOUTHEAST OF OUR REGION OFF THE SOUTHERN NEW ENGLAND COAST. 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...FLOOD WATCH THROUGH LATE TUESDAY NIGHT FOR CTZ001-013. NY...NONE. MA...FLOOD WATCH THROUGH LATE TUESDAY NIGHT FOR MAZ001-025. VT...NONE. && $$ SYNOPSIS...11/JPV NEAR TERM...11 SHORT TERM...11 LONG TERM...WASULA AVIATION...FRUGIS FIRE WEATHER...11 HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS ALBANY NY
126 PM EDT MON JUN 10 2013 .SYNOPSIS... A LOW PRESSURE SYSTEM AND ITS ASSOCIATED FRONTAL BOUNDARIES WILL APPROACH FROM THE OHIO VALLEY AND GREAT LAKES...AND MOVE ACROSS OUR REGION THIS AFTERNOON THROUGH TUESDAY. THIS SYSTEM WILL BRING A WIDESPREAD SOAKING RAINFALL. THE RAIN WILL BE HEAVY AT TIMES...ALONG WITH POSSIBLE THUNDERSTORMS. MAINLY DRY WEATHER IS EXPECTED WEDNESDAY INTO THURSDAY WITH WEAK HIGH PRESSURE BUILDING IN. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1215 PM EDT...ANOTHER WIDESPREAD SOAKING RAINFALL WILL IMPACT THE REGION THROUGH THE DAY TOMORROW. THERE IS THE POTENTIAL FOR FLOODING...MAINLY FOR BERKSHIRE/LITCHFIELD COUNTIES WHERE A FLOOD WATCH HAS BEEN ISSUED. REFER TO HYDROLOGY SECTION FOR DETAILS. THE LATEST MOSAIC RADAR SHOWS THE LEADING EDGE OF THE RAINFALL ALREADY REACHING THE MOHAWK VALLEY....SARATOGA REGION AND EXTREME SOUTHWEST VERMONT WITH STEADY RAIN ACROSS THE CAPITAL REGION...MID HUDSON VALLEY...EASTERN CATSKILLS...BERKSHIRES AND NW CT. WE HAVE SPED UP THE ARRIVAL TIME FOR RAIN ACROSS THE AREA TO ACCOUNT FOR THESE TRENDS. IN ADDITION...WITH THE QUICKER ARRIVAL OF RAIN...TEMPS WON/T HAVE A CHANCE TO RISE AS MUCH AS ANTICIPATED TODAY. MAX TEMPS WILL LIKELY BE IN THE 60S LATE THIS MORNING...AS RAINFALL WILL KEEP TEMPS FROM RISING...AND THEY MAY EVEN FALL A DEGREE OR TWO AS TEMPS WET BULB. THE HEAVIEST RAIN IS EXPECTED TO FALL FROM LATE THIS AFTERNOON OR THIS EVENING THROUGH EARLY TUESDAY MORNING...AS A STRENGTHENING LOW LEVEL JET SEGMENT MOVES ACROSS THE AREA AND DEEP LAYER MOISTURE INCREASES COINCIDENT WITH THE STRONGEST FORCING. 850MB SOUTHERLY WIND ANOMALIES OF +3 TO +4 STDEV AND PRECIPITABLE WATER ANOMALIES OF +2 TO +3 STDEV ARE FORECAST FROM THE GEFS. SOME EMBEDDED CONVECTIVE ELEMENTS ARE POSSIBLE...WHICH COULD LOCALLY ENHANCE RAINFALL AMOUNTS. THIS IS MAINLY DUE TO SOME ELEVATED INSTABILITY AND SURFACE BASED CAPE WILL BE MINIMAL WITH OUR AREA POSITIONED NORTH OF THE ADVANCING WARM FRONT. SO WILL MENTION ISOLATED THUNDER...BUT THE MAIN THREAT WILL BE HEAVY RAIN. VARIOUS SOURCES OF MODEL GUIDANCE IN GENERALLY GOOD AGREEMENT WITH MAIN SYNOPTIC FEATURES THROUGH TONIGHT. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... IT APPEARS MUCH OF THE STEADY AND HEAVIER RAIN WILL BE EXITING THE AREA BY TUESDAY MORNING...AS THE WARM FRONT AND A POSSIBLE WEAK WAVE DEVELOPING ALONG IT SHIFT INTO EASTERN NEW ENGLAND. HOWEVER...THIS WILL NOT SIGNIFY THE END OF OUR RAINFALL AS THE UPPER LEVEL TROUGH AXIS AND SURFACE OCCLUDED FRONT STILL HAVE THE PASS THROUGH DURING THE DAY. SO WILL CONTINUE TO MENTION LIKELY TO CATEGORICAL POPS THROUGH THE DAY ASSOCIATED WITH SHOWERS. SOME DIVERGENCE IN MODEL SOLUTIONS DO START TO OCCUR MAINLY WITH THE POSITION/TRACK OF THE MAIN SURFACE LOW...WHICH WILL TRACK RIGHT OVER OUR AREA OR AT LEAST THE NORTHERN HALF OF THE AREA. THIS WILL HAVE TO BE WATCHED CAREFULLY...SINCE IF A MORE NORTHERN TRACK OCCURS THIS COULD POTENTIALLY PUT AT LEAST THE SOUTHERN HALF OF THE AREA UNDER A THREAT FOR MORE ROBUST CONVECTION IF ENOUGH HEATING CAN TAKE PLACE. THIS SCENARIO IS HIGHLY SPECULATIVE AT THIS TIME...SINCE MUCH OF THE AREA COULD REMAIN SOCKED IN WITH CLOUDS AND THUS NOT ALLOWING FOR HEATING. WITH THE VIGOROUS UPPER TROUGH AXIS PASSING THROUGH...MID LEVEL LAPSE RATES EXPECTED TO STEEPEN ENOUGH TO AT LEAST WARRANT MENTION OF CHANCE THUNDER. AGAIN...THE THREAT FOR STRONGER CONVECTION IS QUITE MUDDLED AT THIS TIME. SHOWERS SHOULD START TO TAPER OFF SOMEWHAT TUESDAY NIGHT...AS THE UPPER TROUGH AXIS SHIFTS EAST OF THE AREA. HOWEVER WITH ONE OR MORE SHORT WAVES EMBEDDED IN THE DEVELOPING NORTHWEST FLOW ALOFT FORECAST TO PASS THROUGH...SCATTERED SHOWERS WILL STILL BE POSSIBLE LATE TUESDAY NIGHT THROUGH WEDNESDAY. AT LEAST PARTIAL SUNSHINE IS EXPECTED ON WEDNESDAY...AS MIXING BECOMES MORE FAVORABLE IN THE LOWER-MID TROPOSPHERE. THE INCREASED MIXING WILL ALSO RESULT IN BREEZY CONDITIONS FROM LATE MORNING INTO EARLY EVENING. ANY SHOWERS SHOULD TEND TO DIMINISH WEDNESDAY NIGHT AS WEAK HIGH PRESSURE BUILDS INTO THE REGION FROM THE GREAT LAKES. && .LONG TERM /THURSDAY THROUGH MONDAY/... CHAOTIC UPPER FLOW SHOULD PREVAIL THURSDAY AND FRIDAY AS ONE UPPER IMPULSE TRACKS JUST SOUTH OF OUR REGION THURSDAY...THEN ANOTHER SYSTEM TRACKS THROUGH NORTHERN AND EASTERN AREAS FRIDAY. MOST OF THE MOISTURE...INSTABILITY AND UPPER DYNAMICS IN THE SYSTEM THURSDAY SHOULD TRACK SOUTH OF OUR REGION...ALTHOUGH SOME SCATTERED SHOWERS ARE POSSIBLE IN THE EASTERN CATSKILLS...MID HUDSON VALLEY AND NW CT. ON FRIDAY...AN AXIS OF INSTABILITY WITHIN NORTHWEST FLOW SHOULD RESULT ISOLATED TO SCATTERED THUNDERSTORMS. AS THE FRIDAY SYSTEM EXITS...THERE SHOULD BE A BRIEF SHOT OF COOLER AIR. HIGHS THURSDAY WITH PERIODS CLOUDS AND SUN...MOSTLY CLOUDY IN SOME AREAS...SHOULD BE IN THE LOWER TO MID 70S...AND AS USUAL COOLER IN HIGHER ELEVATIONS DURING THE ENTIRE PERIOD THURSDAY THROUGH SUNDAY. HIGHS FRIDAY...WITH POTENTIALLY MORE SUN BEFORE THE ISOLATED TO SCATTERED THUNDERSTORMS...SHOULD BE IN THE UPPER 70S TO NEAR 80. BROAD FLAT UPPER RIDGE AXIS BEGINS TO BUILD INTO THE REGION BY SATURDAY WITH A LITTLE BIT OF WARM ADVECTION. THERE SHOULD BE MORE SUN THAN CLOUDS IN MOST AREAS WITH HIGHS IN THE MID TO UPPER 70S. SOME HINTS A ANOTHER QUICK MOVING SMALL UPPER IMPULSE APPROACHING FOR SUNDAY WITH SOME ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY LATE IN THE DAY SUNDAY. THE TIMING AND EXTEND OF ANY SHOWERS AND THUNDERSTORMS CAN BE DETERMINED AS THE EVENT GETS CLOSER. HIGHS SUNDAY IN THE UPPER 70S TO LOWER 80S. && .AVIATION /18Z MONDAY THROUGH FRIDAY/... A STEADY RAIN HAS DEVELOPED ACROSS EASTERN NY AND WESTERN NEW ENGLAND AHEAD OF AN APPROACHING WARM FRONT. MOST OF THE RAINFALL HAS BEEN RATHER LIGHT SO FAR...WHICH HAS KEPT FLYING CONDITIONS GENERALLY VFR. BASED ON UPSTREAM OBS AND THE 3KM HRRR MODEL...AS THE AFTERNOON GOES ON...FLYING CONDITIONS WILL GRADUALLY DECREASE TO MVFR. THIS WILL BE DUE TO THE RAIN PICKING UP IN INTENSITY AND ALLOWING VSBYS TO DROP...ESP FOR THE SOUTHERN TERMINALS OF KPSF/KPOU. IT MAY TAKE UNTIL AFTER 00Z UNTIL KALB/KGFL SEE IFR CONDITIONS. A MODERATE STEADY RAIN IS EXPECTED AT ALL TERMINALS FOR THE LATE EVENING INTO THE FIRST HALF OF THE OVERNIGHT. THIS RAINFALL...ALONG WITH A PERSISTENT SOUTHERLY FLOW...SHOULD ALLOW FOR IFR CONDITIONS AT ALL SITES. LATE TONIGHT...THE STEADY RAIN WILL TAPER OFF...ALLOWING FOR IMPROVEMENT IN THE VSBYS...ALTHOUGH THERE WILL BE PLENTY OF LINGERING LOW LEVEL MOISTURE WHICH WILL KEEP SOME LOW STRATUS CLOUDS AROUND. BY THE MID MORNING HOURS ON TUESDAY...MOST OF THESE LOW CLOUDS SHOULD START TO BREAK UP...ALTHOUGH THERE STILL MAY BE SOME LINGERING SHOWERS AROUND. SFC WINDS ARE NEARLY CALM OR LIGHT OUT OF THE E-SE EARLY THIS AFTN. EVENTUALLY BY LATE IN THE DAY...WINDS WILL BE OUT OF THE SOUTH AROUND 5-10 KTS. WINDS WILL SWITCH TO A W-SW DIRECTION ON TUESDAY AT SIMILAR SPEEDS. OUTLOOK... TUE PM-TUE NIGHT...VFR/MVFR. CHC -SHRA/TSRA WED...VFR...NO SIG WX. THU...VFR/MVFR. CHC -SHRA/TSRA AT KPOU. FRI...VFR. NO SIG WX. && .FIRE WEATHER... NO FIRE WEATHER RELATED CONCERNS EXPECTED FOR AT LEAST THE NEXT SEVERAL DAYS. ANOTHER WIDESPREAD SOAKING RAINFALL IS IN STORE TODAY THROUGH TUESDAY ACROSS THE REGION...BRINGING AT LEAST 1 TO 2 INCHES OF RAIN AND POSSIBLY MORE. && .HYDROLOGY... MORE HEAVY RAIN IN STORE FROM THIS AFTERNOON THROUGH TUESDAY...WHICH MAY RESULT IN SOME FLOODING ESPECIALLY FOR THE BERKSHIRES AND LITCHFIELD HILLS. A LOW PRESSURE SYSTEM AND ITS ASSOCIATED FRONTAL BOUNDARIES WILL SLOWLY CROSS OUR REGION THROUGH TUESDAY. AT THIS TIME IT STILL LOOKS LIKE RAINFALL AMOUNTS WILL BE 1 TO 3 INCHES WITH THE HIGHEST AMOUNTS ACROSS WESTERN NEW ENGLAND. THE HOUSATONIC BASIN WILL ESPECIALLY BE SUSCEPTIBLE TO MINOR FLOODING DUE TO THE COMBINATION OF ALREADY ELEVATED RIVER LEVELS AND HEAVY RAINFALL. THEREFORE A FLOOD WATCH HAS BEEN ISSUED FOR THIS AREA. WILL HOLD OFF ON ANY FLOOD WATCHES FOR THE REST OF THE AREA FOR NOW SINCE EXPECTED QPF IS LOWER OUTSIDE OF WESTERN NEW ENGLAND AND RIVER LEVELS ARE SOMEWHAT LOWER. WILL CONTINUE MENTION OF THE HEAVY RAINFALL POTENTIAL IN THE HWO...WITH THE POSSIBILITY OF SMALL STREAM AND URBAN/POOR DRAINAGE FLOODING. THE HEAVIEST RAIN LOOKS TO FALL FROM THIS EVENING INTO EARLY TUESDAY MORNING. DRYING CONDITIONS ARE EXPECTED FOR WEDNESDAY INTO THURSDAY. 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...FLOOD WATCH FROM 6 PM EDT THIS EVENING THROUGH LATE TUESDAY NIGHT FOR CTZ001-013. NY...NONE. MA...FLOOD WATCH FROM 6 PM EDT THIS EVENING THROUGH LATE TUESDAY NIGHT FOR MAZ001-025. VT...NONE. && $$ SYNOPSIS...FRUGIS/JPV NEAR TERM...FRUGIS/11/JPV SHORT TERM...JPV LONG TERM...NAS AVIATION...FRUGIS FIRE WEATHER...JPV HYDROLOGY...11/JPV
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
424 PM EDT MON JUN 10 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 422 PM EDT MON JUN 10 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER THE SRN ROCKIES EDGING OUT INTO THE SRN PLAINS. TO THE N...A WELL DEFINED MID-LEVEL LOW WAS OVER SASKATCHEWAN. STRONG WRLY FLOW WAS NOTED BTWN THESE TWO FEATURES ALONG THE U.S./CANADIAN BORDER WITH A 110KT UPPER JET ANALYZED BY THE RUC. THIS JET STREAK AND ASSOCIATED SHORTWAVE WILL BE THE NEXT FEATURE OF INTEREST AS IT SHIFTS THRU THE UPPER GREAT LAKES TUE. ANOTHER SHORTWAVE HAS LIFTED THRU NRN ONTARIO TODAY. TAIL END OF SHORTWAVE COMBINED WITH DAYTIME HEATING AND LAKE BREEZE CONVERGENCE HAS RESULTED IN ISOLD/SCT SHRA DEVELOPING OVER WRN UPPER MI TODAY. SO FAR...NO THUNDER EVEN THOUGH LATEST SPC MESOANALYSIS SHOWS SBCAPE/MLCAPE UPWARDS OF 1000/500J/KG OVER THE INTERIOR WRN UPPER MI. DIURNALLY DRIVEN SHRA AND MAYBE YET ISOLD TSRA OVER WRN UPPER MI WILL DISSIPATE THIS EVENING WITH LOSS OF DAYTIME HEATING. AFTER SHRA DISSIPATE...EXPECT A TREND TOWARD CLR/PARTLY CLOUDY SKIES FOR A TIME TONIGHT TO ALLOW FOR SOME FOG TO DEVELOP UNDER MID LEVEL DRYING AND LIGHT/CALM WIND. FOG WILL BE MOST LIKELY WHERE SOME RAIN HAS FALLEN THIS AFTN. LATER TONIGHT...AFOREMENTIONED JET STREAK/SHORTWAVE AND ASSOCIATED DEEP LAYER FORCING WILL BE APPROACHING THE AREA. GIVEN THAT SHRA/TSRA HAVE BEEN OCCURRING ALL DAY WITH FEATURE...IT APPEARS CHC POPS ARE WARRANTED OVER WRN LAKE SUPERIOR INTO NW UPPER MI LATE TONIGHT. INTERESTING FCST FOR TUE WITH REGARD TO TSTM POTENTIAL. MUCH WILL DEPEND ON TIMING OF JET STREAK/SHORTWAVE AND DEGREE OF INSTABILITY. FROM A LARGER SCALE STANDPOINT...THE WNW FLOW PATTERN IS ONE WHICH OFTEN SUPPORTS SVR STORMS OVER UPPER MI. WITH UPPER LEVEL WIND MAX PASSING ACROSS THE AREA...DEEP LAYER SHEAR TUE IS ON THE ORDER OF 60-70KT. FORTUNATELY...WITH MLCAPE UP AROUND 500J/KG FROM THE NAM AND ONLY A FEW HUNDRED FROM THE GFS...INSTABILITY WILL BE LACKING TO TAKE ADVANTAGE OF THE STRONG DEEP LAYER SHEAR...AND FORCING WILL BE PASSING THRU EARLIER IN THE DAY AND MOSTLY LIKELY NOT IN CONCERT WITH PEAK HEATING. THE NAM REPRESENTS THE SLOWER END OF THE SPECTRUM ON THE PROGRESSION TUE WHILE THE GFS IS ON THE FASTER SIDE. THE GEM OFFERS A GOOD COMPROMISE WITH TIMING AND WILL BE FAVORED. PLAN WILL BE TO CARRY SCHC/LOW CHC POPS ACROSS THE AREA FROM WNW TO ESE TUE. BEST CHC OF SHRA/TSRA WILL BE OVER THE SCNTRL/SE WHERE LAKE BREEZE OFF LAKE MI WILL PROVIDE ENHANCED LOW-LEVEL FORCING. PRONOUNCED MIDLEVEL DRYING SURGING INTO THE AREA WILL BRING AN END TO SHRA/TSRA FROM W TO E DURING THE AFTN...AND SKIES WILL LIKELY BECOME SUNNY/MOSTLY SUNNY OVER THE W. IF FOR SOME REASON PROGRESSION IS SLOWER TUE AND INSTABILITY BUILDS HIGHER THAN CURRENTLY EXPECTED... THERE MAY BE A FEW SVR STORMS TO DEAL WITH OVER THE SCNTRL/SE. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 422 PM EDT MON JUN 10 2013 NO SIGNIFICANT WEATHER SYSTEMS...AND NEAR NORMAL TEMPERATURES WILL BE THE RULE FOR MUCH OF THIS LONG TERM PERIOD. EXPECT A FEW LINGERING SHOWERS WILL BE POSSIBLE OVER FAR E AND SE CORNERS OF THE CWA. THE CURRENT LOW ACROSS CENTRAL CANADA WILL OPEN UP AND SWING AROUND THE SET RIDGE OF HIGH PRESSURE OVER MUCH OF THE SOUTHERN U.S...AND MOVE TO SD/NE BY WEDNESDAY MORNING. THIS WAVE WILL LINE UP WITH A SECONDARY WAVE SWINGING AROUND THE LARGE LOW OVER NE CANADA ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT INTO THURSDAY MORNING. EVEN WITH ALL OF THAT...UPPER MI MAY END UP DRY WEDNESDAY NIGHT INTO THURSDAY. DID ADD A JUST A FEW SHOWERS FOR FAR E UPPER MI /FIRE ZONES/ THURSDAY AFTERNOON. THE MAIN RESULT WILL BE ADDITIONAL CLOUDS. KEPT THE MENTION OF PATCHY FOG OVER THE GREAT LAKES THROUGH THURSDAY EVENING...BEFORE HIGH PRESSURE SINKS IN FROM THE NW. 850MB TEMPS OFF THE ECMWF STAY AROUND 8C FROM THURSDAY THROUGH MUCH OF FRIDAY. EXPECT TEMPS TO COOL BACK INTO THE 60S NEAR LAKE SUPERIOR BOTH THURSDAY AND FRIDAY...EVEN IN THE UPPER 50S F RIGHT ALONG THE SHORELINE. WITH THE 500MB TROUGHS SHIFTING TO OUR E AND A HIGH AMPLITUDE RIDGE STRETCHING FROM TX THROUGH CENTRAL CANADA...EXPECT NW FLOW TO RETURN ALOFT. HIGH TEMPS SHOULD RISE INTO THE MID AND UPPER 70S FOR THE UPCOMING WEEKEND. THE WEEKEND STILL LOOKS UP IN THE AIR...WITH A SMALL CHANCE OF PRECIP SATURDAY AFTERNOON WEST...LINGERING ACROSS THE ENTIRE AREA THROUGH SUNDAY. THERE REMAINS ENOUGH DIFFERENCES TO NOT GO HIGHER THAN CHANCE...WITH MODERATE TO LOW CONFIDENCE IN THE ONGOING FORECAST FROM SATURDAY THROUGH MONDAY. THE EARLIER 10/00Z RUN OF THE ECMWF AND 10/12Z RUN OF THE GFS BOTH PAINTED A GOOD AMOUNT OF PRECIP FOR THE CWA...WHICH WHEN BLENDED RESULTED IN HIGH CHANCE POPS FOR MONDAY. SINCE THEN OF COURSE THE 01/12Z RUN OF THE ECMWF HAS COME IN MAINLY DRY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 138 PM EDT MON JUN 10 2013 WITH INCREASING INSTABILITY...SCT SHRA WILL CONTINUE TO DEVELOP OVER WRN UPPER MI THIS AFTN. THESE SHRA WILL MAINLY AFFECT THE AREAS AROUND KIWD/KSAW BEFORE THEY DISSIPATE BY 00Z WITH WANING DAYLIGHT. WITH UNCERTAINTY IN WHETHER A SHRA WILL ACTUALLY IMPACT EITHER TERMINAL...ONLY VCSH WILL BE UTILIZED. OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EARLY EVENING. A WEAK HIGH PRES WILL MOVE IN THIS EVENING...AND WITH LIGHT WINDS AND JUST SOME PATCHY HIGHER CLOUDS...SETUP LOOKS GOOD FOR SOME FOG TO FORM WITH IFR CONDITIONS APPEARING LIKELY. DISTURBANCE RAPIDLY APPROACHING FROM THE W MAY BRING VCNTY SHRA TO KCMX LATE TONIGHT AND TO KIWD/KSAW TUE MORNING. INCREASE IN CLOUDS SHOULD CAUSE RADIATION FOG TO DISSIPATE AT KCMX LATE TONIGHT...BUT WILL LIKELY NEED TO WAIT UNTIL AFTER SUNRISE AT KIWD/KSAW FOR FOG TO DISSIPATE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 422 PM EDT MON JUN 10 2013 WEAK PRES GRADIENT WILL RESULT IN WINDS GENERALLY 15KT OR LESS THRU THE WEEK. SLIGHTLY STRONGER WINDS UP TO 20KT MAY OCCUR OVER PORTIONS OF CNTRL/ERN LAKE SUPERIOR LATE WED NIGHT/THU IN ADVANCE OF HIGH PRES BUILDING TOWARD LAKE SUPERIOR. WITH RAINFALL THAT OCCURRED TODAY OVER WRN LAKE SUPERIOR...THERE WILL PROBABLY BE SOME FOG PATCHES OVER WRN LAKE SUPERIOR TONIGHT. IF SO...FOG PATCHES WILL SHIFT TO ERN LAKE SUPERIOR TUE AS WINDS BECOME WESTERLY. THE PATCHY FOG MAY THEN LINGER THU. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
140 PM EDT MON JUN 10 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 412 AM EDT MON JUN 10 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW AN UPR RDG EXTENDING FM NW ONTARIO THRU THE GREAT LKS TO THE MID ATLANTIC COAST. THERE ARE 2 CLOSED LOWS UPSTREAM...ONE MOVING THRU THE MID MS RIVER VALLEY AND ANOTHER OVER SASKATCHEWAN TO THE N OF MEAN RDG OVER THE WRN CONUS. A SHRTWV IS MOVING INTO NE MN BTWN THE 2 CLOSED LOWS AND GENERATING AN AREA RA OVER FAR NW LK SUP AND NE MN AS THE DPVA/ DEEP LYR QVECTOR CNVGC AHEAD OF THIS FEATURE INTERACTS WITH DEEP MSTR SHOWN ON THE 00Z INL RAOB. BUT SINCE THE DEEPER MSTR AND FORCING ASSOCIATED WITH THE CLOSED LO IN THE MID MS RIVER VALLEY ARE TO THE S OF UPR MI...THERE IS NO DYNAMIC SUPPORT FOR PCPN OVER UPR MI...WITH AN ABSENCE OF SGNFT RADAR RETURNS OVER THE AREA DESPITE MOCLDY SKIES. THE CLDS HAVE LIMITED THE DIURNAL FALL OF TEMP...WITH MOST PLACES REPORTING TEMPS IN THE 50S TO LO 60S EARLY THIS MRNG. SOME BREAKS IN THE CLDS ARE MOVING NE INTO UPR MI FM WI. THICKER CLDS/SOME ISOLD -SHRA ARE MOVING N THRU LWR MI. MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS ASSOCIATED WITH SHRTWV NOW MOVING THRU NE MN. TDAY...SHRTWV IN NE MN IS PROGGED TO LIFT NEWD INTO NW ONTARIO ON THE SE FLANK OF NEARLY STNRY CLOSED LO OVER SASKATCHEWAN. DPVA/H85-5 QVECTOR CNVGC ASSOCIATED WITH THIS FEATURE ARE PROGGED TO BRUSH THE NW CWA INTO THIS AFTN BEFORE THE SHRTWV LIFTS FARTHER TO THE NE AND GIVES WAY TO DNVA/DEEP LYR QVECTOR DVGC/MID LVL DRYING. MODELS SHOW BULK OF PCPN ACCOMPANYING THIS SHRTWV PASSAGE REMAINING TO THE NW OF EVEN THE KEWEENAW. SO OPTED TO CUT POPS TO NO HIER THAN SCHC THIS MRNG OVER THE LAND CWA. DID ADD SCHC POPS OVER THE E TO ACCOUNT FOR ISOLD -SHRA MOVING N THRU NRN LWR MI. EVEN AFT THE DYNAMIC SUPPORT SWINGS TO THE N THIS AFTN...BULK OF RECENT NUMERICAL GUIDANCE IS GENERATING QPF OVER MAINLY THE INTERIOR W HALF OF THE CWA AS DAYTIME HEATING DESTABILIZES THE ATMOSPHERE AND LK BREEZE BNDRYS PROVIDE SOME LLVL FOCUS. TENDED TO RAISE FCST MAX TEMPS A FEW DEGREES TO ACCOUNT FOR SOME BREAKS IN THE CLDS MOVING NE FM WI AND ABSENCE OF DYNAMIC FORCING OVER MOST OF THE FA. THE ONLY EXCEPTION WAS THE E... WHERE MORE CLDS STREAMING NWD THRU LWR MI MIGHT HOLD DOWN THE DIURNAL TEMP INCRS. EVEN THOUGH WARMING/DRYING ABV H6 WITH THE ARRIVAL OF THE NEGATIVE DYNAMICS SETS IN AFT 18Z AND WL LIMIT POTENTIAL FOR DEEP CNVCTN...MODIFIED NAM FCST SDNG FOR THE INTERIOR W FOR SFC T/TD OF 75/57 YIELDS SBCAPE NEAR 450 J/KG AND KINX OF 33. GOING CHC POPS/SCHC OF TS LOOKS TO BE IN PRETTY GOOD ORDER. TNGT...IN THE ABSENCE OF ANY DYNAMIC SUPPORT...EXPECT DIURNAL SHRA OVER MAINLY THE W HALF TO DIMINISH THIS EVNG WITH LOSS OF DAYTIME HEATING. ALTHOUGH ANOTHER SHRTWV IS PROGGED TO RACE EWD ALONG THE CNDN BORDER THRU TNGT IN THE FAST WLY FLOW ON THE SRN FLANK OF THE SASKATCHEWAN CLOSED LO AND APRCH THE NW CWA LATER WITH SOME DPVA/DEEP LYR QVECTOR CNVGC...FAIRLY DRY MID LVLS/LLVL ACYC FLOW/ ABSENCE OF ANY DIURNAL HEATING WL LIMIT ACCOMPANYING POPS... ESPECIALLY SINCE THE FOCUS OF THE ASSOCIATED FORCING IS FCST TO PASS TO THE N. DID RETAIN SOME CHC POPS OVER THE NW CWA TO ACCOUNT FOR THIS DISTURBANCE. OTRW...EXPECT SOME FOG TO FORM OVER THE INTERIOR WITH THE MID LVL DRYING/LGT WINDS...ESPECIALLY IN AREAS WHERE SOME RA MIGHT FALL THIS AFTN AND FURTHER MOISTEN THE LLVLS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 412 AM EDT MON JUN 10 2013 LARGER SCALE PATTERN BY TUESDAY INDICATES STRING OF TROUGHS ACROSS CANADA AND TROUGHING OVER NORTHWEST CONUS AND NORTHEAST CONUS. SHALLOW RIDGING IS ANCHORED OVER SOUTH CENTRAL CONUS. THROUGH REST OF THE WEEK TROUGHING OVER CANADA SPLITS WITH RIDGING ATTEMPTING TO BUILD INTO CANADIAN PRAIRIES. EVENTUALLY THIS RIDGE MOVES EAST INTO NORTHERN PLAINS AND UPPER GREAT LAKES BY START OF NEXT WEEKEND. YET ANOTHER TROUGH WILL THEN SWING BACK ACROSS UPPER LAKES TO CLOSE THE WEEKEND. OVERALL PATTERN WILL NOT BRING MUCH RAIN TO UPPER LAKES BUT IT ALSO SHOULD NOT BE THAT COLD EITHER AS BULK OF COLDER AIR STAYS LOCKED UP OVER WESTERN AND EASTERN CANADA CLOSER TO MORE PERSISTENT TROUGHING. TEMPS INLAND FROM LK SUPERIOR AND NEAR LK MICHIGAN MOST DAYS WILL BE AT OR ABOVE NORMAL. TEMPS ALONG LK SUPERIOR WILL BE AT OR SLIGHTLY BLO NORMAL MOST OF THE TIME SINCE PREVAILING WINDS WILL BE ONSHORE. WARMEST DAYS WILL BE TUESDAY AND AGAIN ON SATURDAY WITH MOST AREAS WELL INTO THE 70S. COOLEST DAY THIS WEEK FOR ALL AREAS SHOULD BE ON THURSDAY WHEN TEMPS ALONG LK SUPERIOR WILL LIKELY STAY IN THE 50S. WEAK SHORTWAVE TROUGH AND POCKET OF H85-H7 MOISTURE SWINGS ACROSS WESTERN AND CENTRAL CWA ON TUESDAY MORNING THEN OVR EASTERN CWA DURING AFTN HOURS. THOUGH SHARPEST LIFT IN FORM OF H85-H7 Q-VECTOR CONVERGENCE IMPACTS LK SUPERIOR AND ISLE ROYALE/KEWEENAW PENINSULA THROUGH MIDDAY...RIBBON OF LIFT CROSSES REST OF CWA AS WELL. WEAK FORCING AND SUBTLE MOISTENING POINTS TO LOW CHANCE POPS. BUT...KIND OF SIMILAR TO TODAY...COULD SEE ISOLD DAYTIME SHRA AND EVEN TSRA AS SFC CAPES POP UP TO 300-500J/KG OVR SCNTRL IN THE AFTN. H7-H5 WINDS 45-55KT RESULTING IN DEEP LAYER SHEAR OVR 30 KTS. DO NOT EXPECT THERE TO BE ENOUGH INSTABILITY TO TAKE ADVANTAGE OF THE STRONGER SHEAR THOUGH SO DO NOT EXPECT ANY STRONG STORMS. DEEP DRYING IN H7 LAYER QUICKLY ENDS ANY SHRA/TSRA BY LATE TUE AFTN. H7 DRYING AND NEUTRAL HEIGHTS SHOULD KEEP CONDITIONS DRY THROUGH REST OF TUESDAY NIGHT. ON WEDNESDAY...SHORTWAVE TROUGH SLIDES FROM ROCKIES TOWARD UPPER MISSISSIPPI RIVER VALLEY. SFC LOW/WARM FRONT SET UP FROM NEB INTO NORTHERN IL WHILE H85 WARM FRONT IS NOT MUCH FARTHER THAN THAT. EDGE OF H7 MOISTURE MIGHT MAKE IT INTO NORTHERN WI...BUT SINCE 1-6KM MUCAPE IS BARELY INTO SOUTHERN MN AND CNTRL WI...HAVE HARD TIME THINKING THAT THE INCREASE IN H7 MOSITURE WOULD RESULT IN NOTHING MORE THAN A FEW SPRINKLES OUT OF A SCT-BKN MID CLOUD DECK. NOT WORTH PUTTING ANY POPS INTO SOUTHERN CWA. OTHER THING TO WATCH ON WEDNESDAY IS SHORTWAVE TIED INTO NORTHERN STREAM TROUGH PUSHING INTO ONTARIO. TREND IS FOR WAVE TO BE STRONGER...BUT MAJORITY OF MODELS KEEP WAVE ON WNW-ESE TRACK OVER NORTHERN LK SUPERIOR IN THE MORNING AND OVER ONTARIO EAST OF SAULT STE MARIE BY AFTN. SFC BASED INSTABILITY AND STEEPER H7-H5 LAPSE RATES SHOULD SPUR ON SCATTERED SHRA/TSRA NORTH AND EAST OF LK SUPERIOR WITH DAYTIME HEATING. ONLY THE GEM-NH SHOWS THE WAVE DIGGING ENOUGH SOUTH TO HAVE ANY QPF OVR UPR MICHIGAN THOUGH AND THAT IS ONLY OVR FAR EAST CWA. MAJORITY RULES FOR NOW SO HAVE NOT PUT ANY POPS IN OVER THE EAST. MAX TEMPS MAY SHOW VARIATION CLOSER TO LK SUPERIOR AS LAKE COOLING IS ENHANCED BY AFTN WITH DEVELOPING NORTH GRADIENT FLOW. MAY SEE TEMPS QUICKLY RISE WEDNESDAY MORNING CLOSER TO LK SUPERIOR THEN FALL OFF IN THE AFTN. FARTHER INLAND...EXPECT ANOTHER DAY WITH HIGHS INTO THE 70S. SHORTWAVE PASSAGE RESULTS IN H85-H7 WINDS VEERING MORE NORTH LATER WEDNESDAY NIGHT INTO THURSDAY. H85 THERMAL TROUGH ALSO PRESENT. NOT EXPECTING ANY SHRA AS FORCING IS MINIMAL...BUT MAY SEE DECENT CLOUD COVER IN THE MORNING. BY AFTN...H85 RH PROGS SHOWING LAKE STABILIZING SIGNAL WITH MINIMUM RH SHOWING UP OVR LK SUPERIOR AFT 18Z. PROBABLY WILL SEE CLEARING DEVELOP CLOSER TO LK SUPERIOR AND OVER EAST DUE TO STABILIZING FLOW. EVEN WITH CLEARING WILL BE COOL DAY ALONG LK SUPERIOR AS MOST LOCATIONS STAY IN THE 50S WITH STIFF NORTHERLY WINDS. INLAND TEMPS WILL BE IN THE UPR 60S TO PERHAPS LOWER 70S. HIGH PRESSURE BUILDS ACROSS THURSDAY NIGHT THROUGH FRIDAY AND NOW EVEN THROUGH MOST OF FRIDAY NIGHT. MOSTLY CLEAR SKIES WILL PREVAIL AND GIVEN TREND OF HIGH STAYING AROUND LONGER...FRIDAY NIGHT NOW LOOKING GENERALLY FREE OF ANY SHRA/TSRA EXCEPT FAR WEST CWA. WEEKEND FORECAST MUDDLED AS MID CONUS RIDGE FLATTENS OUT FROM NORTHERN PLAINS TO UPPER GREAT LAKES. STRONGER SHORTWAVE TROUGHS CUTTING THROUGH THE RIDGE FORECAST TO BE OVR CNTRL CANADA AND OVR THE MIDDLE MISSISSIPPI RIVER VALLEY. TALKING DAY 6 AND 7 SO HARD TO GET TOO HUNG UP ON THESE TYPE OF DETAILS YET. OVERALL THEME THOUGH IS SLOWER ARRIVAL OF SHRA/TSRA CHANCES AND/OR A GENERAL LACKING FOCUS FOR SHRA/TSRA. CONSENSUS POPS IN THE LOW CHANCE RANGE USED BUT DID PULL POPS OVER EASTERN CWA ON SATURDAY AS THAT AREA IS IN CLOSER PROXIMITY OF STUBBORN SFC RIDGING. TEMPS FOR NEXT WEEKEND SHOULD BE SIMILAR TO READINGS THIS WEEK WITH HIGHS MAINLY IN THE 70S AND POSSIBLY WARMER IF THERE ARE LESS CLOUDS/SHRA/TSRA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 138 PM EDT MON JUN 10 2013 WITH INCREASING INSTABILITY...SCT SHRA WILL CONTINUE TO DEVELOP OVER WRN UPPER MI THIS AFTN. THESE SHRA WILL MAINLY AFFECT THE AREAS AROUND KIWD/KSAW BEFORE THEY DISSIPATE BY 00Z WITH WANING DAYLIGHT. WITH UNCERTAINTY IN WHETHER A SHRA WILL ACTUALLY IMPACT EITHER TERMINAL...ONLY VCSH WILL BE UTILIZED. OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EARLY EVENING. A WEAK HIGH PRES WILL MOVE IN THIS EVENING...AND WITH LIGHT WINDS AND JUST SOME PATCHY HIGHER CLOUDS...SETUP LOOKS GOOD FOR SOME FOG TO FORM WITH IFR CONDITIONS APPEARING LIKELY. DISTURBANCE RAPIDLY APPROACHING FROM THE W MAY BRING VCNTY SHRA TO KCMX LATE TONIGHT AND TO KIWD/KSAW TUE MORNING. INCREASE IN CLOUDS SHOULD CAUSE RADIATION FOG TO DISSIPATE AT KCMX LATE TONIGHT...BUT WILL LIKELY NEED TO WAIT UNTIL AFTER SUNRISE AT KIWD/KSAW FOR FOG TO DISSIPATE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 412 AM EDT MON JUN 10 2013 AS LO PRES IN THE LOWER GREAT LAKES SHIFTS SLOWLY TO THE E TODAY... EXPECT E-SE WINDS UP TO 20 KTS TO SLOWLY DIMINISH W-E WITH THE WEAKENING PRES GRADIENT AND UNDER 15 KTS TONIGHT. DID MAINTAIN PATCHY FOG OVER MUCH OF THE WESTERN LAKE WHERE SOME SHOWERS HAVE FURTHER MOISTENED THE LOW LEVELS. THE WEAK PRES GRADIENT WILL PREVAIL THRU FRI...SO PLAN ON WINDS UNDER 15 KTS TUE THRU FRI. COULD BE A BRIEF PERIOD OF STRONGER WINDS...UP TO 20 KTS IN GUSTS...LATE WEDNESDAY NIGHT AND THURSDAY MORNING. RELATIVELY MOIST AIR OVER THE STILL CHILLY LAKE WATERS WILL RESULT IN LINGERING FOG PATCHES UNTIL DRIER AIR ARRIVES ON FRI. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...ROLFSON MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
649 PM EDT MON JUN 10 2013 .SYNOPSIS... LOW PRESSURE SYSTEM AND FRONT WILL MOVE ACROSS NEW YORK AND PENNSYLVANIA TONIGHT AND TUESDAY BRINGING OCCASIONAL SHOWERS. A RUMBLE OF THUNDER IS POSSIBLE THIS EVENING. WEDNESDAY WILL SEE SOMEWHAT OF A BREAK IN THE WEATHER BEFORE THE NEXT SYSTEM MOVES IN THURSDAY. THE CHANCE FOR RAIN THURSDAY WILL BE HIGHER ACROSS PENNSYLVANIA AND LOWER ACROSS NEW YORK TOWARD THE LAKES. && .NEAR TERM /THROUGH TUESDAY/... 630 PM EDT UPDATE... MADE MINOR CHANGES TO THE FORECAST. INCREASED POPS IN THE WEST PORTIONS OF THE CWA AS A BAND OF LIGHT RAIN SHOWERS IS MOVING IN FROM CENTRAL PA. CURRENT ANALYSIS IS INDICATING THAT MID LVL FRONTOGENSIS IS TAKING PLACE OVER CENTRAL NY...WHICH SHOULD SERVE AS A FOCUSING MECHANISM FOR HEAVY RAINFALL THIS EVENING. WE`LL HAVE TO MONITOR THE POTENTIAL FOR FLASH FLOODING OVER THE CATSKILLS AND NE PA THIS EVENING...WHICH IS THE REGION OF THE HIGHEST PWAT VALUES. OTHER THEN THAN...PREVIOUS FORECAST HOLDS GOOD. 230 PM UPDATE... RAINFALL SO FAR TODAY HAS BEEN IN THE QUARTER TO LESS THAN HALF INCH RAIN. MAYBE A FEW BREAKS HERE IN THE SHOWERS AND THEN HI RES MODELS HAVE A GOOD BATCH OF PCPN MOVING THROUGH IN THE 00Z TO 03Z TIME FRAME. HRRR IS A LITTLE SLOWER THAN THE ARW. ARW HAS BEEN DOING WELL WITH ITS FCSTS. THIS EVENING SEEMS LIKE THE BEST CHANCE FOR HEAVY RAIN AND ANY THUNDER. PRIMARY FOCUS AREA REMAINS OVER NE PA AND THE CATSKILLS. LOCALIZED FLASH FLOODING WILL HAVE TO BE MONITORED BUT OVER 2 INCHES IS NEEDED IN 3 HOURS WHICH WOULD NEED A CLUSTER OF GOOD CONVECTION TO TRIGGER THIS AND THAT DOES NOT SEEM LIKELY. TOWARD MORNING SCATTERED LIGHT SHOWERS OR OCCASSIONAL OR EVEN DRIZZLE IS LIKELY. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... UPR LEVEL LOW MOVES ACROSS NY TUESDAY HELPING TRIGGER MORE SHOWERS. TUESDAY NIGHT STILL HAVE CYCLONIC NW FLOW AND A FAVORABLE JET REGION. SHORT WAVE RIDGE BUILDS IN WEDNESDAY AHEAD OF THE NEXT SYSTEM. BEST CHANCE AT DRY WEATHER. WARM FRONT PUSHES IN THURSDAY WITH A JET ENTRANCE REGION. MODELS HAVE BEEN TRENDING FURTHER N EACH RUN WITH THE CLOUDS AND PCPN. MAIN FOCUS AND TRACK OF THE CENTER REMAINS WELL TO OUR SOUTH THURSDAY BUT MODELS ARE SETTING UP A BAND OF GOOD RAIN ACROSS PA NRN TIER AND SOME IN THE NY SRN TIER. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... 230 PM UPDATE...MED RNG FCST FOLLOWED CLOSELY THE WPC GUIDANCE FOR THIS PD. CHCS FOR -SHRA ASSCD WITH LOW PRES DEPARTING THE MID ALTC RGN ON THU NGT (MAINLY SRN NY AND NE PA)...THEN THE PSBLTY OF SCT- SHRA ON FRI WITH PASSING S/WV`S IN NW FLOW. AFTER THAT...SFC HI PRES IS XPCT TO BUILD INTO THE RGN FOR A NICE WEEKEND WITH MAXES GNRLY IN THE L/M70S. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS LOW PRES TRACKS FROM THE LOWER GTLAKES TWDS THE ST LAWRENCE VLY LATER TNGT...WE XPCT WDSPRD IFR/MVFR THIS AFTN INTO THE OVRNGT HRS DUE TO RAIN/DZ/CIGS AND VSBY`S...WITH SOME TERMINALS (SPCLY ITH/BGM/ELM) SEEING CONDITIONS BLO ALT MINS AT TIMES. MAIN BATCH OF RAIN IS XPCTD TO SLIDE OFF TO THE EAST LATER THIS EVNG...WITH MORE SHRA LIKELY TMRW MRNG INTO EARLY AFTN WITH PSSG OF THE UPR TROF AXIS. PLENTY OF LOW LVL MSTR AND XPCT IFR/MVFR TO LINGER INTO TMRW MRNG AT MOST SITES. WINDS THIS AFTN GNRLY FROM THE SE AT 10-15 KTS WITH G15-20 HIER ELEVATIONS...BECMG SRLY LATER TNGT 5-10 KTS THEN WSW ON TUE 10-15KTS. OUTLOOK... TUE...IFR/MVFR WITH SHOWERS AND TSTMS. WED THROUGH FRI...MAINLY VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...BMW NEAR TERM...BMW/KAH SHORT TERM...BMW LONG TERM... AVIATION...
AREA FORECAST DISCUSSION
NWS BUFFALO NY
436 PM EDT MON JUN 10 2013 .SYNOPSIS... LOW PRESSURE WILL MOVE ACROSS THE REGION TONIGHT...BRINGING WIDESPREAD SHOWERS AND PERHAPS A FEW THUNDERSTORMS. THIS LOW WILL EXIT INTO NEW ENGLAND ON TUESDAY...WITH A RETURN TO FAIR AND SEASONABLY WARM WEATHER ON WEDNESDAY. MAINLY DRY AND SEASONABLE WEATHER SHOULD PERSIST THROUGH THE END OF THE WEEK AS HIGH PRESSURE BUILDS SOUTH FROM CENTRAL CANADA. && .NEAR TERM /THROUGH TUESDAY/... FOR THE REMAINDER OF TODAY...STEADY SHOWERS WILL LIFT ACROSS LAKE ONTARIO AND ACROSS THE EASTERN LAKE ONTARIO REGION. THIS AREA APPEARS TO BE LINED UP WITH AN AREA OF WARM AIR ADVECTION IN THE MID-LEVELS...WITH A GENERAL NORTHWARD PROGRESSION LIKELY GIVEN THE FLOW ALOFT AND NAM/RGEM/GFS MODEL GUIDANCE. NOTED THE HRRR HAS NOT CAPTURED THIS AREA WELL...AND THUS CANNOT BE USED TO FORECAST THIS FEATURE. IN ADDITION...THERE IS ANOTHER AREA OF SHOWERS WITH SOME EMBEDDED THUNDERSTORMS DEVELOPING ACROSS NORTHERN OHIO AND WESTERN PENNSYLVANIA. THIS AREA ROUGHLY LINES UP WITH THE LEADING EDGE OF AN UPPER LEVEL TROF...WITH THE HRRR SHOWING SOME SKILL IN CAPTURING THIS SHOWER DEVELOPMENT. GIVEN THE SLOW EASTWARD PROGRESSION OF THE UPPER LOW...EXPECT THIS TO DRIFT INTO WESTERN PORTIONS OF THE SOUTHERN TIER EARLY EVENING...WITH SHOWERS SPREADING NORTH AND EAST OVERNIGHT. THIS IS ALSO IN LINE WITH NAM/SREF/RGEM GUIDANCE...WHICH ALSO SHOWS SOME ENHANCEMENT ACROSS NW PORTIONS OF THE NIAGARA FRONTIER WHERE THE LOW WILL ENHANCED SURFACE CONVERGENCE. ALL THIS SUGGESTS THAT WHILE MANY MAY GET A BREAK FROM THE RAIN LATE THIS AFTERNOON...MORE IS ON THE WAY. THUS FAR UPSTREAM LIGHTNING ACTIVITY IS QUITE LIMITED...AND IT NOW APPEARS THE BEST CHANCE FOR ANY THUNDERSTORMS WILL BE THIS EVENING AS THE LOW AND UPPER LOW MOVE ACROSS THE REGION. MEAN QPFS CONTINUE TO RUN IN THE .50 TO 1.00 INCH RANGE THROUGH TONIGHT...WITH THE GREATEST AMOUNTS LIKELY TO BE EAST OF LAKE ONTARIO...AND ACROSS NW PORTIONS OF NIAGARA FRONTIER. WITH PRECIPITABLE WATER VALUES BETWEEN 1.50 AND 1.75 INCHES...LOCALLY HIGHER AMOUNTS ARE POSSIBLE...BUT GIVEN THE TIME BETWEEN WAVES IT WOULD LIKELY TAKE SLOW MOVING OR TRAINING CONVECTION TO CAUSE ANY FLOODING. THIS POTENTIAL APPEARS TO BE LIMITED. OTHERWISE...TEMPERATURES WILL DROP VERY LITTLE OVERNIGHT...WITH LOWS ONLY IN THE LOWER TO MID 60S. PATCHY FOG MAY DEVELOP AS THE SURFACE LOW CROSSES THE LAKES THIS EVENING. ON TUESDAY...THE OPENING 500 MB TROF AXIS WILL BE ACROSS EASTERN PORTIONS OF THE CWA...WITH IT FORECAST TO CONTINUE TO SLOWLY TRACK EASTWARD DURING THE DAY. THIS WILL RESULT IN LINGERING SHOWER ACTIVITY DURING THE DAY...WITH THE MOST WIDESPREAD ACTIVITY ACROSS EASTERN PORTIONS. EXPECT CLOUDS TO LINGER MOST OF THE DAY...LIMITING HIGHS TO THE MID AND UPPER 60S...AND PERHAPS 70 ACROSS THE NIAGARA FRONTIER. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... TUESDAY NIGHT A WEAK MID LEVEL CLOSED LOW WILL FORM OVER SOUTHEAST QUEBEC AND SLOWLY DRIFT ACROSS NORTHERN NEW ENGLAND ON WEDNESDAY. AT THE SURFACE AN ASSOCIATED WEAK LOW WILL TAKE A SIMILAR...ALBEIT SLIGHTLY FARTHER SOUTH TRACK FROM NORTHEAST NY TUESDAY EVENING TO THE GULF OF MAINE BY WEDNESDAY. THIS SYSTEM WILL MAINTAIN MOIST CYCLONIC FLOW ACROSS THE NORTH COUNTRY TUESDAY NIGHT THROUGH WEDNESDAY MORNING WITH A FEW LINGERING SHOWERS AND CLOUDS... ESPECIALLY ACROSS THE HIGHER TERRAIN WITH AN ADDED BOOST FROM UPSLOPE FLOW. A FEW SHOWERS MAY ALSO LINGER TUESDAY EVENING ACROSS MUCH OF CENTRAL AND WESTERN NY MAINLY INLAND FROM THE LAKES WITH LINGERING LOW LEVEL MOISTURE AND WEAK INSTABILITY. THESE SHOWERS FARTHER WEST WILL QUICKLY DIMINISH LATER TUESDAY EVENING WITH THE LOSS OF DAYTIME HEATING. LATER WEDNESDAY THE CLOSED LOW WILL PULL AWAY FROM NEW ENGLAND WITH DEEPER MOISTURE SLOWLY DIMINISHING ACROSS THE NORTH COUNTRY. THIS SHOULD ALLOW ANY LINGERING SHOWERS TO END...ALTHOUGH A GOOD AMOUNT OF CLOUD COVER WILL LINGER. FARTHER WEST...12Z MODEL GUIDANCE REMAINS CONSISTENT IN DEVELOPING A CORRIDOR OF CONVECTION FROM THE MIDWEST INTO OHIO AND PA BY THE END OF THE DAY. THIS SHOULD REMAIN SAFELY TO OUR SOUTHWEST...LEAVING MUCH OF THE CWA IN A WEAK SURFACE RIDGE BETWEEN THE TWO SYSTEMS. THIS SHOULD ALLOW FOR AT LEAST SOME PARTIAL SUNSHINE WITH TEMPERATURES VERY CLOSE TO AVERAGE. WEDNESDAY NIGHT INTO THURSDAY MEDIUM RANGE GUIDANCE TAKES A SERIES OF MID LEVEL SHORTWAVES AND ASSOCIATED COMPLEXES OF SHOWERS AND THUNDERSTORMS ACROSS THE UPPER MIDWEST AND OHIO VALLEY...THE STRONGEST OF WHICH APPEARS TO BE LATE WEDNESDAY NIGHT AND THURSDAY. THIS PARTICULAR SYSTEM CAN BE TRACED TO A VIGOROUS CLOSED LOW OVER CALIFORNIA AND NEVADA THIS AFTERNOON. THIS SYSTEM WILL CREST OVER THE TOP OF THE SOUTH CENTRAL CONUS RIDGE AND FORCE CONVECTION ALONG A BAROCLINIC ZONE OVER THE UPPER MIDWEST. THE NAM REMAINS OUT OF SYNC WITH THE REST OF THE MODEL GUIDANCE IN TAKING THIS SYSTEM MUCH FARTHER NORTH ON THURSDAY AND WILL BE DISCOUNTED. FOLLOWING THE CONSENSUS OF THE GFS/GEM/ECMWF...THE LAST STRONGEST SYSTEM LATE WEDNESDAY NIGHT AND THURSDAY MAY PASS CLOSE ENOUGH THROUGH OHIO AND PA TO BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE WESTERN SOUTHERN TIER...BUT STILL EXPECT THE BULK OF IT TO STAY SOUTH OF THE AREA AND CLOSER TO MORE ROBUST INSTABILITY OVER THE OHIO VALLEY. OTHERWISE FOR THE REST OF THE AREA EXPECT AT LEAST PARTIAL SUNSHINE DURING THE DAY THURSDAY WITH TEMPERATURES JUST SLIGHTLY COOLER THAN WEDNESDAY AS NORTHERLY FLOW INCREASES ON THE NORTHERN PERIPHERY OF THE LOW PASSING THROUGH PA. THURSDAY NIGHT THE MID LEVEL SHORTWAVE AND ASSOCIATED SURFACE LOW WILL RACE OFF THE EAST COAST WITH ANY SHOWER CHANCE ACROSS THE SOUTHERN TIER ENDING. NORTHERLY FLOW WILL TAKE HOLD AS A NORTHERN STREAM TROUGH BEGINS TO AMPLIFY WITH THE FIRST SHORTWAVE...WHICH WILL DRAG A COOLER AND DRIER AIRMASS INTO THE GREAT LAKES AND NORTHEAST. && .LONG TERM /FRIDAY THROUGH MONDAY/... A PERIOD OF DRIER WEATHER WILL FINALLY MAKE AN APPEARANCE FOR MUCH OF THE LONG TERM...ALTHOUGH THERE ARE A FEW WEAK SYSTEMS OF INTEREST. THE GENERAL PATTERN WILL FEATURE AN AMPLIFYING TROUGH ACROSS NORTHERN NEW ENGLAND AND THE CANADIAN MARITIMES OVER THE WEEKEND...WHICH WILL MAINTAIN NORTHWEST FLOW ACROSS THE GREAT LAKES REGION. THE ECMWF IS MORE AMPLIFIED WITH THIS PATTERN THAN THE GFS...WHICH WOULD KEEP THE WEEKEND A LITTLE COOLER. THE TROUGH WILL BE FAR ENOUGH EAST TO KEEP OUR REGION IN A GENERALLY DRY CONFLUENT NORTHWEST FLOW WITH HIGH PRESSURE BUILDING IN AT THE SURFACE. A NORTHERN STREAM SHORTWAVE WILL DIG SOUTH ACROSS THE AREA ON FRIDAY ON THE LEADING EDGE OF THE TROUGH. THE MORE AMPLIFIED ECMWF REMAINS MORE AGGRESSIVE WITH THIS FEATURE AND DEVELOPS SHOWERS ACROSS THE AREA ON FRIDAY AIDED BY DAYTIME HEATING. FOR NOW WILL FAVOR THE LESS AMPLIFIED GFS SOLUTION AND KEEP FRIDAY MAINLY DRY WITH JUST AN INCREASE IN CLOUDS WITH THE TROUGH PASSAGE. OVER THE WEEKEND SURFACE HIGH PRESSURE WILL BUILD OVER THE GREAT LAKES. THIS SHOULD KEEP BOTH DAYS DRY WITH SEASONABLE TEMPERATURES. IF THE LESS AMPLIFIED GFS VERIFIES TEMPS MAY CREEP A LITTLE ABOVE AVERAGE. BY SUNDAY NIGHT AND MONDAY BOTH THE GFS AND ECMWF BRING THE NEXT TROUGH INTO THE GREAT LAKES. SOUTHWEST RETURN FLOW WILL INCREASE AHEAD OF THIS SYSTEM AND BRING INCREASING MOISTURE ALONG WITH INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS. && .AVIATION /21Z MONDAY THROUGH SATURDAY/... LOW PRESSURE WILL LIFT FROM THE OHIO VALLEY AND ACROSS LAKE ERIE/ONTARIO TONIGHT. AHEAD OF THIS...EXPECT MIXED CONDITIONS IN AND OUT OF SHOWERS...WITH PREDOMINANTLY VFR/MVFR CONDITIONS AT MOST TAF LOCATIONS. STEADIER RAINS WILL MOVE IN AHEAD OF AND WITH THE LOW THIS EVENING...WITH CIGS EXPECTED TO DROP SIGNIFICANTLY WITH THE WIND SHIFT AS THE LOW PASSES THROUGH. IFR CONDITIONS ARE LIKELY LATE TONIGHT IN LOW CIGS...AND LINGERING RAIN SHOWERS. THERE IS A SLIGHT CHANCE OF A THUNDERSTORM THIS EVENING...WITH WIDESPREAD LIGHTNING UNLIKELY. ON TUESDAY...EXPECT IFR CONDITIONS TO GRADUALLY IMPROVE TO MVFR/VFR AS DRIER AIR BUILDS IN. THIS MAY TAKE MOST OF THE DAY...WITH THE UPPER TROF SLOWLY EXITING EAST OF THE REGION DURING THE AFTERNOON HOURS OUTLOOK... TUESDAY NIGHT...MAINLY MVFR. A CHANCE OF SHOWERS EAST...WITH LINGERING LOW CLOUDS. WEDNESDAY...MVFR IMPROVING TO VFR. THURSDAY THROUGH SATURDAY...MAINLY VFR. && .MARINE... EASTERLY WINDS WILL INCREASE EARLY THIS EVENING AHEAD OF AN AREA OF LOW PRESSURE PUSHING INTO THE OHIO VALLEY. THIS WILL PRODUCE SOME CHOPPY WAVE CONDITIONS ON WESTERN LAKE ONTARIO HOWEVER THESE WILL LIKELY REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THIS LOW WILL PASS JUST NORTH OF THE REGION TUESDAY AND COULD POSSIBLY PRODUCE A BRIEF PERIOD OF SMALL CRAFT CONDITIONS ON LAKE ERIE AS WINDS FUNNEL DOWN THE LAKE. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...APFFEL NEAR TERM...APFFEL SHORT TERM...HITCHCOCK LONG TERM...HITCHCOCK AVIATION...APFFEL MARINE...APFFEL/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
341 PM EDT MON JUN 10 2013 .SYNOPSIS... LOW PRESSURE WILL MOVE ACROSS THE REGION TONIGHT...BRINGING WIDESPREAD SHOWERS AND PERHAPS A FEW THUNDERSTORMS. THIS LOW WILL EXIT INTO NEW ENGLAND ON TUESDAY...WITH A RETURN TO FAIR AND SEASONABLY WARM WEATHER ON WEDNESDAY. MAINLY DRY AND SEASONABLE WEATHER SHOULD PERSIST THROUGH THE END OF THE WEEK AS HIGH PRESSURE BUILDS RIDGES IN FROM CENTRAL CANADA. && .NEAR TERM /THROUGH TUESDAY/... FOR THE REMAINDER OF TODAY...STEADY SHOWERS WILL LIFT ACROSS LAKE ONTARIO AND ACROSS THE EASTERN LAKE ONTARIO REGION. THIS AREA APPEARS TO BE LINED UP WITH AN AREA OF WARM AIR ADVECTION IN THE MID-LEVELS...WITH A GENERAL NORTHWARD PROGRESSION LIKELY GIVEN THE FLOW ALOFT AND NAM/RGEM/GFS MODEL GUIDANCE. NOTED THE HRRR HAS NOT CAPTURED THIS AREA WELL...AND THUS CANNOT BE USED TO FORECAST THIS FEATURE. IN ADDITION...THERE IS ANOTHER AREA OF SHOWERS WITH SOME EMBEDDED THUNDERSTORMS DEVELOPING ACROSS NORTHERN OHIO AND WESTERN PENNSYLVANIA. THIS AREA ROUGHLY LINES UP WITH THE LEADING EDGE OF AN UPPER LEVEL TROF...WITH THE HRRR SHOWING SOME SKILL IN CAPTURING THIS SHOWER DEVELOPMENT. GIVEN THE SLOW EASTWARD PROGRESSION OF THE UPPER LOW...EXPECT THIS TO DRIFT INTO WESTERN PORTIONS OF THE SOUTHERN TIER EARLY EVENING...WITH SHOWERS SPREADING NORTH AND EAST OVERNIGHT. THIS IS ALSO IN LINE WITH NAM/SREF/RGEM GUIDANCE...WHICH ALSO SHOWS SOME ENHANCEMENT ACROSS NW PORTIONS OF THE NIAGARA FRONTIER WHERE THE LOW WILL ENHANCED SURFACE CONVERGENCE. ALL THIS SUGGESTS THAT WHILE MANY MAY GET A BREAK FROM THE RAIN LATE THIS AFTERNOON...MORE IS ON THE WAY. THUS FAR UPSTREAM LIGHTNING ACTIVITY IS QUITE LIMITED...AND IT NOW APPEARS THE BEST CHANCE FOR ANY THUNDERSTORMS WILL BE THIS EVENING AS THE LOW AND UPPER LOW MOVE ACROSS THE REGION. MEAN QPFS CONTINUE TO RUN IN THE .50 TO 1.00 INCH RANGE THROUGH TONIGHT...WITH THE GREATEST AMOUNTS LIKELY TO BE EAST OF LAKE ONTARIO...AND ACROSS NW PORTIONS OF NIAGARA FRONTIER. WITH PRECIPITABLE WATER VALUES BETWEEN 1.50 AND 1.75 INCHES...LOCALLY HIGHER AMOUNTS ARE POSSIBLE...BUT GIVEN THE TIME BETWEEN WAVES IT WOULD LIKELY TAKE SLOW MOVING OR TRAINING CONVECTION TO CAUSE ANY FLOODING. THIS POTENTIAL APPEARS TO BE LIMITED. OTHERWISE...TEMPERATURES WILL DROP VERY LITTLE OVERNIGHT...WITH LOWS ONLY IN THE LOWER TO MID 60S. PATCHY FOG MAY DEVELOP AS THE SURFACE LOW CROSSES THE LAKES THIS EVENING. ON TUESDAY...THE OPENING 500 MB TROF AXIS WILL BE ACROSS EASTERN PORTIONS OF THE CWA...WITH IT FORECAST TO CONTINUE TO SLOWLY TRACK EASTWARD DURING THE DAY. THIS WILL RESULT IN LINGERING SHOWER ACTIVITY DURING THE DAY...WITH THE MOST WIDESPREAD ACTIVITY ACROSS EASTERN PORTIONS. EXPECT CLOUDS TO LINGER MOST OF THE DAY...LIMITING HIGHS TO THE MID AND UPPER 60S...AND PERHAPS 70 ACROSS THE NIAGARA FRONTIER. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... TUESDAY NIGHT A WEAK MID LEVEL CLOSED LOW WILL FORM OVER SOUTHEAST QUEBEC AND SLOWLY DRIFT ACROSS NORTHERN NEW ENGLAND ON WEDNESDAY. AT THE SURFACE AN ASSOCIATED WEAK LOW WILL TAKE A SIMILAR...ALBEIT SLIGHTLY FARTHER SOUTH TRACK FROM NORTHEAST NY TUESDAY EVENING TO THE GULF OF MAINE BY WEDNESDAY. THIS SYSTEM WILL MAINTAIN MOIST CYCLONIC FLOW ACROSS THE NORTH COUNTRY TUESDAY NIGHT THROUGH WEDNESDAY MORNING WITH A FEW LINGERING SHOWERS AND CLOUDS... ESPECIALLY ACROSS THE HIGHER TERRAIN WITH AN ADDED BOOST FROM UPSLOPE FLOW. A FEW SHOWERS MAY ALSO LINGER TUESDAY EVENING ACROSS MUCH OF CENTRAL AND WESTERN NY MAINLY INLAND FROM THE LAKES WITH LINGERING LOW LEVEL MOISTURE AND WEAK INSTABILITY. THESE SHOWERS FARTHER WEST WILL QUICKLY DIMINISH LATER TUESDAY EVENING WITH THE LOSS OF DAYTIME HEATING. LATER WEDNESDAY THE CLOSED LOW WILL PULL AWAY FROM NEW ENGLAND WITH DEEPER MOISTURE SLOWLY DIMINISHING ACROSS THE NORTH COUNTRY. THIS SHOULD ALLOW ANY LINGERING SHOWERS TO END...ALTHOUGH A GOOD AMOUNT OF CLOUD COVER WILL LINGER. FARTHER WEST...12Z MODEL GUIDANCE REMAINS CONSISTENT IN DEVELOPING A CORRIDOR OF CONVECTION FROM THE MIDWEST INTO OHIO AND PA BY THE END OF THE DAY. THIS SHOULD REMAIN SAFELY TO OUR SOUTHWEST...LEAVING MUCH OF THE CWA IN A WEAK SURFACE RIDGE BETWEEN THE TWO SYSTEMS. THIS SHOULD ALLOW FOR AT LEAST SOME PARTIAL SUNSHINE WITH TEMPERATURES VERY CLOSE TO AVERAGE. WEDNESDAY NIGHT INTO THURSDAY MEDIUM RANGE GUIDANCE TAKES A SERIES OF MID LEVEL SHORTWAVES AND ASSOCIATED COMPLEXES OF SHOWERS AND THUNDERSTORMS ACROSS THE UPPER MIDWEST AND OHIO VALLEY...THE STRONGEST OF WHICH APPEARS TO BE LATE WEDNESDAY NIGHT AND THURSDAY. THIS PARTICULAR SYSTEM CAN BE TRACED TO A VIGOROUS CLOSED LOW OVER CALIFORNIA AND NEVADA THIS AFTERNOON. THIS SYSTEM WILL CREST OVER THE TOP OF THE SOUTH CENTRAL CONUS RIDGE AND FORCE CONVECTION ALONG A BAROCLINIC ZONE OVER THE UPPER MIDWEST. THE NAM REMAINS OUT OF SYNC WITH THE REST OF THE MODEL GUIDANCE IN TAKING THIS SYSTEM MUCH FARTHER NORTH ON THURSDAY AND WILL BE DISCOUNTED. FOLLOWING THE CONSENSUS OF THE GFS/GEM/ECMWF...THE LAST STRONGEST SYSTEM LATE WEDNESDAY NIGHT AND THURSDAY MAY PASS CLOSE ENOUGH THROUGH OHIO AND PA TO BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE WESTERN SOUTHERN TIER...BUT STILL EXPECT THE BULK OF IT TO STAY SOUTH OF THE AREA AND CLOSER TO MORE ROBUST INSTABILITY OVER THE OHIO VALLEY. OTHERWISE FOR THE REST OF THE AREA EXPECT AT LEAST PARTIAL SUNSHINE DURING THE DAY THURSDAY WITH TEMPERATURES JUST SLIGHTLY COOLER THAN WEDNESDAY AS NORTHERLY FLOW INCREASES ON THE NORTHERN PERIPHERY OF THE LOW PASSING THROUGH PA. THURSDAY NIGHT THE MID LEVEL SHORTWAVE AND ASSOCIATED SURFACE LOW WILL RACE OFF THE EAST COAST WITH ANY SHOWER CHANCE ACROSS THE SOUTHERN TIER ENDING. NORTHERLY FLOW WILL TAKE HOLD AS A NORTHERN STREAM TROUGH BEGINS TO AMPLIFY WITH THE FIRST SHORTWAVE...WHICH WILL DRAG A COOLER AND DRIER AIRMASS INTO THE GREAT LAKES AND NORTHEAST. && .LONG TERM /FRIDAY THROUGH MONDAY/... A PERIOD OF DRIER WEATHER WILL FINALLY MAKE AN APPEARANCE FOR MUCH OF THE LONG TERM...ALTHOUGH THERE ARE A FEW WEAK SYSTEMS OF INTEREST. THE GENERAL PATTERN WILL FEATURE AN AMPLIFYING TROUGH ACROSS NORTHERN NEW ENGLAND AND THE CANADIAN MARITIMES OVER THE WEEKEND...WHICH WILL MAINTAIN NORTHWEST FLOW ACROSS THE GREAT LAKES REGION. THE ECMWF IS MORE AMPLIFIED WITH THIS PATTERN THAN THE GFS...WHICH WOULD KEEP THE WEEKEND A LITTLE COOLER. THE TROUGH WILL BE FAR ENOUGH EAST TO KEEP OUR REGION IN A GENERALLY DRY CONFLUENT NORTHWEST FLOW WITH HIGH PRESSURE BUILDING IN AT THE SURFACE. A NORTHERN STREAM SHORTWAVE WILL DIG SOUTH ACROSS THE AREA ON FRIDAY ON THE LEADING EDGE OF THE TROUGH. THE MORE AMPLIFIED ECMWF REMAINS MORE AGGRESSIVE WITH THIS FEATURE AND DEVELOPS SHOWERS ACROSS THE AREA ON FRIDAY AIDED BY DAYTIME HEATING. FOR NOW WILL FAVOR THE LESS AMPLIFIED GFS SOLUTION AND KEEP FRIDAY MAINLY DRY WITH JUST AN INCREASE IN CLOUDS WITH THE TROUGH PASSAGE. OVER THE WEEKEND SURFACE HIGH PRESSURE WILL BUILD OVER THE GREAT LAKES. THIS SHOULD KEEP BOTH DAYS DRY WITH SEASONABLE TEMPERATURES. IF THE LESS AMPLIFIED GFS VERIFIES TEMPS MAY CREEP A LITTLE ABOVE AVERAGE. BY SUNDAY NIGHT AND MONDAY BOTH THE GFS AND ECMWF BRING THE NEXT TROUGH INTO THE GREAT LAKES. SOUTHWEST RETURN FLOW WILL INCREASE AHEAD OF THIS SYSTEM AND BRING INCREASING MOISTURE ALONG WITH INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... LOW PRESSURE WILL LIFT FROM THE OHIO VALLEY AND ACROSS LAKE ERIE/ONTARIO TONIGHT. AHEAD OF THIS...EXPECT MIXED CONDITIONS IN AND OUT OF SHOWERS...WITH PREDOMINANTLY VFR/MVFR CONDITIONS AT MOST TAF LOCATIONS. STEADIER RAINS WILL MOVE IN AHEAD OF AND WITH THE LOW THIS EVENING...WITH CIGS EXPECTED TO DROP SIGNIFICANTLY WITH THE WIND SHIFT AS THE LOW PASSES THROUGH. IFR CONDITIONS ARE LIKELY LATE TONIGHT IN LOW CIGS...AND LINGERING RAIN SHOWERS. THERE IS A SLIGHT CHANCE OF A THUNDERSTORM THIS EVENING...WITH WIDESPREAD LIGHTNING UNLIKELY. ON TUESDAY...EXPECT IFR CONDITIONS TO GRADUALLY IMPROVE TO MVFR/VFR AS DRIER AIR BUILDS IN. THIS MAY TAKE MOST OF THE DAY...WITH THE UPPER TROF SLOWLY EXITING EAST OF THE REGION DURING THE AFTERNOON HOURS OUTLOOK... TUESDAY NIGHT...MAINLY MVFR. A CHANCE OF SHOWERS EAST...WITH LINGERING LOW CLOUDS. WEDNESDAY...MVFR IMPROVING TO VFR. THURSDAY THROUGH SATURDAY...MAINLY VFR. && .MARINE... EASTERLY WINDS WILL INCREASE EARLY THIS EVENING AHEAD OF AN AREA OF LOW PRESSURE PUSHING INTO THE OHIO VALLEY. THIS WILL PRODUCE SOME CHOPPY WAVE CONDITIONS ON WESTERN LAKE ONTARIO HOWEVER THESE WILL LIKELY REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THIS LOW WILL PASS JUST NORTH OF THE REGION TUESDAY AND COULD POSSIBLY PRODUCE A BRIEF PERIOD OF SMALL CRAFT CONDITIONS ON LAKE ERIE AS WINDS FUNNEL DOWN THE LAKE. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...APFFEL NEAR TERM...APFFEL SHORT TERM...HITCHCOCK LONG TERM...HITCHCOCK AVIATION...APFFEL MARINE...APFFEL/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
237 PM EDT MON JUN 10 2013 .SYNOPSIS... LOW PRESSURE SYSTEM AND FRONT WILL MOVE ACROSS NEW YORK AND PENNSYLVANIA TONIGHT AND TUESDAY BRINGING OCCASSIONAL SHOWERS. A RUMBLE OF THUNDER IS POSSIBLE THIS EVENING. WEDNESDAY WILL SEE SOMEWHAT OF A BREAK IN THE WEATHER BEFORE THE NEXT SYSTEM MOVES IN THURSDAY. THE CHANCE FOR RAIN THURSDAY WILL BE HIGHER ACROSS PENNSYLVANIA AND LOWER ACROSS NEW YORK TOWARD THE LAKES. && .NEAR TERM /THROUGH TONIGHT/... 230 PM UPDATE... RAINFALL SO FAR TODAY HAS BEEN IN THE QUARTER TO LESS THAN HALF INCH RAIN. MAYBE A FEW BREAKS HERE IN THE SHOWERS AND THEN HI RES MODELS HAVE A GOOD BATCH OF PCPN MOVING THROUGH IN THE 00Z TO 03Z TIME FRAME. HRRR IS A LITTLE SLOWER THAN THE ARW. ARW HAS BEEN DOING WELL WITH ITS FCSTS. THIS EVENING SEEMS LIKE THE BEST CHANCE FOR HEAVY RAIN AND ANY THUNDER. PRIMARY FOCUS AREA REMAINS OVER NE PA AND THE CATSKILLS. LOCALIZED FLASH FLOODING WILL HAVE TO BE MONITORED BUT OVER 2 INCHES IS NEEDED IN 3 HOURS WHICH WOULD NEED A CLUSTER OF GOOD CONVECTION TO TRIGGER THIS AND THAT DOES NOT SEEM LIKELY. TOWARD MORNING SCATTERED LIGHT SHOWERS OR OCCASSIONAL OR EVEN DRIZZLE IS LIKELY. && .SHORT TERM /TUESDAY THROUGH THURSDAY/... UPR LEVEL LOW MOVES ACROSS NY TUESDAY HELPING TRIGGER MORE SHOWERS. TUESDAY NIGHT STILL HAVE CYCLONIC NW FLOW AND A FAVORABLE JET REGION. SHORT WAVE RIDGE BUILDS IN WEDNESDAY AHEAD OF THE NEXT SYSTEM. BEST CHANCE AT DRY WEATHER. WARM FRONT PUSHES IN THURSDAY WITH A JET ENTRANCE REGION. MODELS HAVE BEEN TRENDING FURTHER N EACH RUN WITH THE CLOUDS AND PCPN. MAIN FOCUS AND TRACK OF THE CENTER REMAINS WELL TO OUR SOUTH THURSDAY BUT MODELS ARE SETTING UP A BAND OF GOOD RAIN ACROSS PA NRN TIER AND SOME IN THE NY SRN TIER. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... 230 PM UPDATE...MED RNG FCST FOLLOWED CLOSELY THE WPC GUIDANCE FOR THIS PD. CHCS FOR -SHRA ASSCD WITH LOW PRES DEPARTING THE MID ALTC RGN ON THU NGT (MAINLY SRN NY AND NE PA)...THEN THE PSBLTY OF SCT- SHRA ON FRI WITH PASSING S/WV`S IN NW FLOW. AFTER THAT...SFC HI PRES IS XPCT TO BUILD INTO THE RGN FOR A NICE WEEKEND WITH MAXES GNRLY IN THE L/M70S. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS LOW PRES TRACKS FROM THE LOWER GTLAKES TWDS THE ST LAWRENCE VLY LATER TNGT...WE XPCT WDSPRD IFR/MVFR THIS AFTN INTO THE OVRNGT HRS DUE TO RAIN/DZ/CIGS AND VSBY`S...WITH SOME TERMINALS (SPCLY ITH/BGM/ELM) SEEING CONDITIONS BLO ALT MINS AT TIMES. MAIN BATCH OF RAIN IS XPCTD TO SLIDE OFF TO THE EAST LATER THIS EVNG...WITH MORE SHRA LIKELY TMRW MRNG INTO EARLY AFTN WITH PSSG OF THE UPR TROF AXIS. PLENTY OF LOW LVL MSTR AND XPCT IFR/MVFR TO LINGER INTO TMRW MRNG AT MOST SITES. WINDS THIS AFTN GNRLY FROM THE SE AT 10-15 KTS WITH G15-20 HIER ELEVATIONS...BECMG SRLY LATER TNGT 5-10 KTS THEN WSW ON TUE 10-15KTS. OUTLOOK... TUE...IFR/MVFR WITH SHOWERS AND TSTMS. WED THROUGH FRI...MAINLY VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...BMW NEAR TERM...BMW SHORT TERM...BMW LONG TERM... AVIATION...
AREA FORECAST DISCUSSION
NWS BUFFALO NY
221 PM EDT MON JUN 10 2013 .SYNOPSIS... WEAK HIGH PRESSURE WILL DRIFT AWAY FROM THE REGION ALLOWING AN AREA OF LOW PRESSURE TO MOVE IN FROM THE OHIO VALLEY. THIS LOW WILL SLOWLY CROSS THE REGION TODAY AND TUESDAY WITH WIDESPREAD RAIN AND PERHAPS A FEW THUNDERSTORMS. DRY WEATHER WILL RETURN WEDNESDAY AND SHOULD CONTINUE THROUGH THE REST OF THE WEEK AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. && .NEAR TERM /THROUGH TONIGHT/... THROUGH EARLY AFTERNOON...RADAR SHOWS SHOWERS ACROSS THE REGION...WITH THE STEADIEST ACTIVITY AT 200 PM EXTENDING BETWEEN I-90 AND THE SOUTH SHORES OF LAKE ONTARIO...WITH ANOTHER STEADY W-E BAND NORTH OF LAKE ONTARIO. THESE AREAS BOTH APPEAR TO BE ALIGNED WITH TWO WAVES OF WARM AIR ADVECTION IN THE MID-LEVELS. MODEL GUIDANCE HAS STRUGGLED TO RESOLVE THIS...WITH MUCH OF THE GUIDANCE MERGING THESE TWO WAVES...UNABLE TO RESOLVE THE BREAKS. MEANWHILE...THE HRRR HAS UNDERDONE THE RAIN ALONG THIS BOUNDARY. DESPITE THE MIXED MODEL PERFORMANCE...TRENDS CONSISTENTLY LIFT BOTH AREAS OF STEADIER RAIN SHOWERS GRADUALLY TO THE NORTH THROUGH THE AFTERNOON HOURS. BEHIND THIS...IS MORE SCATTERED SHOWER ACTIVITY ACROSS WESTERN PENNSYLVANIA. GIVEN SUPPORT FROM THE NAM/SREF/RGEM...SUSPECT THE HRRR FORECAST OF EXPANDING THIS AND MOVING IT INTO FAR WESTERN NEW YORK THIS EVENING WILL BE CORRECT...BRINGING A RETURN TO STEADIER RAINS. MEANWHILE THE SURFACE LOW IS FORECAST TO LIFT ACROSS THE LOWER LAKES FROM LAKE ERIE THIS EVENING TO LAKE ONTARIO OVERNIGHT. SUSPECT THIS WILL BRING YET ANOTHER ROUND OF PRECIPITATION...AS THE ASSOCIATED UPPER TROF MOVES ACROSS WITH THE SURFACE LOW...AND WITH ENHANCED CONVERGENCE WITH THE SURFACE LOW AND ITS ASSOCIATED WIND FIELD. THUS FAR UPSTREAM LIGHTNING ACTIVITY IS QUITE LIMITED...AND IT NOW APPEARS THE BEST CHANCE FOR ANY THUNDERSTORMS WILL BE THIS EVENING AS THE LOW AND UPPER LOW MOVE ACROSS THE REGION. MEAN QPFS CONTINUE TO RUN IN THE .50 TO 1.00 INCH RANGE THROUGH TONIGHT...WITH THE GREATEST AMOUNTS LIKELY TO BE EAST OF LAKE ONTARIO...AND ACROSS NW PORTIONS OF NIAGARA FRONTIER. WITH PRECIPITABLE WATER VALUES BETWEEN 1.50 AND 1.75 INCHES...LOCALLY HIGHER AMOUNTS ARE POSSIBLE...BUT GIVEN THE TIME BETWEEN WAVES IT WOULD LIKELY TAKE SLOW MOVING OR TRAINING CONVECTION TO CAUSE ANY FLOODING. THIS POTENTIAL APPEARS TO BE LIMITED. OTHERWISE...TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THE REMAINDER OF THE AFTERNOON...TOPPING OUT IN THE UPPER 60S TO LOWER 70S. THEN FOR TONIGHT...EXPECT ONLY MODEST DROP INTO THE LOWER TO MID 60S. PATCHY FOG MAY DEVELOP AS THE SURFACE LOW CROSSES THE LAKES THIS EVENING. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... THE BULK OF THE RAIN WILL MOVE OFF TO THE NORTH AND EAST AS THE SURFACE LOW CROSSES NEW YORK STATE DURING TUESDAY. WILL SEE SOME REGENERATION OF THE LOW ACROSS NORTHERN NY AND NEW ENGLAND ON TUESDAY NIGHT AS THE UPPER LOW DEEPENS WHEN IT INTERCEPTS ANOTHER JET STREAK. WILL HAVE LINGERING LIKELY POPS ACROSS THE LOWER SAINT LAWRENCE VALLEY...ON THE RIVER BUT OUTSIDE OF OUR FORECAST AREA...AND WANING CHANCE POPS FOR THE REST OF THE FORECAST AREA FOR TUESDAY NIGHT. AN UNSETTLED UPPER LEVEL PATTERN WILL KEEP THE NEED FOR CHANCE POPS DURING WEDNESDAY AS A SERIES OF WAVES AND VORTICITY MAXIMA ALOFT STREAM BY IN THE NORTHWESTERLY FLOW. WEAK LOW PRESSURE PASSING BY TO THE SOUTH WILL BRING SOME HIGHER CHANCE POPS ACROSS THE SOUTHERN TIER FOR WED AFTERNOON AND EVENING. A WEAK REGION OF HIGH PRESSURE WILL SETTLE OVER NEW YORK STATE WEDNESDAY NIGHT WITH A CLEARING TREND AND BREAK FROM THE RAIN CHANCES. TEMPERATURES WILL BE SLIGHTLY BELOW NORMAL ON TUESDAY AS THE DEPARTING LOW DRAWS DOWN SOME MARGINALLY COOLER AIR IN ITS WAKE. HIGHS WILL BE IN THE MID 60S ACROSS THE NORTH COUNTRY TO THE UPPER 60S AND LOW 70S ELSEWHERE. LOWS TUESDAY NIGHT IN THE MID TO UPPER 50S WILL REFLECT THE REMNANT MOISTURE FROM THE PREVIOUS RAINFALL AND LACK OF ANY REAL AIRMASS CHANGE FOLLOWING THE DEPARTURE OF THE SURFACE LOW. AN INFLUX OF WARMER AIR ALONG AND AHEAD OF WEAK LOW PRESSURE WILL BUMP HIGH TEMPS UP A BIT ON WEDNESDAY WITH HIGHS IN THE LOWER 70S ACROSS THE NORTH COUNTRY AND THE MID 70S ELSEWHERE. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ON THURSDAY...A WEAK SURFACE RIDGE SHOULD BE IN PLACE OVER NY...WITH DRY WEATHER EXPECTED. A BACK DOOR COLD FRONT MAY MOVE ACROSS THE NORTH COUNTRY ON FRIDAY...BUT OTHER THAN KNOCK OFF A FEW DEGREES FROM DAYTIME HIGHS...THIS SHOULD HAVE LITTLE IF ANY EFFECT ON THE WEATHER. HIGH PRESSURE HAS BEEN FORECAST FOR DAYS NOW OVER THE STATE FOR SATURDAY FOR A HIGH CONFIDENCE DRY DAY. SUNDAY IS NOT QUITE LOCKED IN HOWEVER...WITH SEVERAL MODELS BRINGING THE NEXT ROUND OF SHOWERS INTO THE STATE. THE LATEST GFS HOLDS THIS OFF UNTIL SUNDAY EVENING. FOR TEMPERATURES...WITHOUT ANY PRONOUNCED RIDGING OR TROUGHING OVER THE REGION...EXPECT HIGHS AND LOWS THROUGHOUT THE LATTER HALF OF THE WEEK TO BE WITHIN A FEW DEGREES OF NORMAL. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... LOW PRESSURE WILL LIFT FROM THE OHIO VALLEY AND ACROSS LAKE ERIE/ONTARIO TONIGHT. AHEAD OF THIS...EXPECT MIXED CONDITIONS IN AND OUT OF SHOWERS...WITH PREDOMINANTLY VFR/MVFR CONDITIONS AT MOST TAF LOCATIONS. STEADIER RAINS WILL MOVE IN WITH THE LOW...WITH CIGS EXPECTED TO DROP SIGNIFICANTLY WITH THE WIND SHIFT AS THE LOW PASSES THROUGH. IFR CONDITIONS ARE LIKELY LATE TONIGHT IN LOW CIGS...AND LINGERING RAIN SHOWERS. THERE IS A SLIGHT CHANCE OF A THUNDERSTORM THIS EVENING...WITH WIDESPREAD LIGHTNING UNLIKELY. ON TUESDAY...EXPECT IFR CONDITIONS TO GRADUALLY IMPROVE TO MVFR/VFR AS DRIER AIR BUILDS IN. THIS MAY TAKE MOST OF THE DAY...WITH THE UPPER TROF SLOWLY EXITING EAST OF THE REGION DURING THE AFTERNOON HOURS OUTLOOK... TUESDAY...MVFR WITH SHOWERS. WEDNESDAY...MVFR IMPROVING TO VFR. THURSDAY AND FRIDAY...MAINLY VFR. && .MARINE... EASTERLY WINDS WILL INCREASE TODAY AHEAD OF AN AREA OF LOW PRESSURE PUSHING INTO THE OHIO VALLEY..PRODUCING SOME CHOPPY WAVE CONDITIONS ON WESTERN LAKE ONTARIO ALTHOUGH CONDITIONS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THIS LOW WILL PASS JUST NORTH OF THE REGION TUESDAY AND COULD POSSIBLY PRODUCE A BRIEF PERIOD OF SMALL CRAFT CONDITIONS ON LAKE ERIE AS WINDS FUNNEL DOWN THE LAKE. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...TMA NEAR TERM...APFFEL SHORT TERM...WCH LONG TERM...ZAFF AVIATION...APFFEL MARINE...APFFEL/TMA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1252 PM CDT MON JUN 10 2013 .UPDATE... ISSUED AT 1252 PM CDT MON JUN 10 2013 OTHER THAN MAKING MINOR ADJUSTMENTS TO THE HOURLY SENSIBLE WEATHER GRIDS...THERE WERE NO MAJOR UPDATES MADE TO THE ONGOING FORECAST. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT. UPDATE ISSUED AT 1000 AM CDT MON JUN 10 2013 FOG HAS DISSIPATED ACROSS THE JAMES RIVER VALLEY. AS A RESULT...THE DENSE FOG ADVISORY WAS CANCELLED. WATER VAPOR IMAGERY NICELY DEPICTS AN UPPER LOW OVER CENTRAL SASKATCHEWAN THIS MORNING. A JET STREAK ON THE SOUTHERN PERIPHERY OF THIS FEATURE IS NOSING ITS WAY ACROSS NORTH DAKOTA...AND HAS SPARKED A FEW THUNDERSTORMS ACROSS NORTHERN NORTH DAKOTA EAST OF HIGHWAY 83. THE LATEST SHORT RANGE MODEL GUIDANCE PROGS THIS ACTIVITY TO CONTINUE TO PUSH EAST OF THE CWA AS THE JET STREAK SHIFTS EAST OF THE REGION. OTHERWISE...UPDATED TO THE FORECAST TO ADJUST POPS BASED ON CURRENT RADAR OBS AND HRRR TRENDS. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT. UPDATE ISSUED AT 630 AM CDT MON JUN 10 2013 MAIN UPDATE WAS TO EXPAND THE COVERAGE OF SHOWERS AND THUNDERSTORMS THIS MORNING. STRONG UPPER LEVEL JET STREAK COMBINED WITH SURFACE LOW PRESSURE MOVING FROM WEST TO EAST ACROSS NORTH DAKOTA PROVIDING PLENTY OF LIFT FOR PRECIPITATION GIVEN RELATIVELY HIGH BOUNDARY LAYER MOISTURE IN PLACE. A FEW STRONGER STORMS POPPING UP...HOWEVER MUCAPE AT AROUND 100 J/KG IS LIMITING THE SEVERE POTENTIAL. A FEW MORE HUNDRED JOULES AND WOULD THINK SEVERE CRITERIA WOULD EASILY BE MET FOR SOME STORMS GIVEN THE FORCING IN PLACE. DENSE FOG ADVISORY SPOT ON...NO CHANGES NEEDED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 413 AM CDT MON JUN 10 2013 THE MAIN FORECAST CHALLENGE WILL BE DETERMINING THE CHANCES AND AREAL EXTENT OF EXPECTED SHOWERS AND THUNDERSTORMS FOR TODAY AND TONIGHT...AND THE DEVELOPING FOG IN THE JAMES RIVER VALLEY. CURRENTLY...A LOW PRESSURE CENTER WAS OVER EASTERN WYOMING WITH A TROUGH EXTENDING NORTHEASTWARD ACROSS WESTERN NORTH DAKOTA AND INTO SOUTHEASTERN SASKATCHEWAN. WEST OF THIS TROUGH WINDS WERE GENERALLY OUT OF THE NORTH. EAST OF THE TROUGH WINDS WERE SOUTHEASTERLY WITH PLENTY OF LOW LEVEL MOISTURE. A LARGE AREA OF FOG EXTENDED ACROSS MUCH OF IOWA AND MINNESOTA...AND HAS SPREAD INTO THE EASTERN DAKOTAS. DENSE FOG HAD DEVELOPED OVER THE SHEYENNE RIVER VALLEY AND HAS SPREAD INTO THE JAMES RIVER VALLEY. OAKES REPORTED 1/4 MILE VISIBILITY...AND JAMESTOWN WAS VARYING BETWEEN 3/4 AND 3 MILES. EXPECT THAT THE DENSE FOG WILL SPREAD NORTHWARD INTO JAMESTOWN...AND WILL ISSUE A DENSE FOG ADVISORY FOR FOSTER/STUTSMAN/LAMOURE/LOGAN COUNTIES - ALONG THE JAMES RIVER VALLEY - UNTIL 10 AM CDT. AT THE SURFACE...THE AFOREMENTIONED TROUGH OVER WESTERN NORTH DAKOTA EXTENDED BETWEEN TWO LOW PRESSURE SYSTEMS - ONE OVER CENTRAL SASKATCHEWAN AND THE OTHER OVER EASTERN WYOMING. AT UPPER LEVELS...A LARGE LOW WAS STACKED OVER THE SURFACE LOW IN SASKATCHEWAN WITH SEVERAL VORT ENERGY IMPULSES ROTATING AROUND THE LOW. THE UPPER FLOW ACROSS NORTH DAKOTA...ON THE SOUTHERN END OF THE UPPER LOW`S INFLUENCE...WAS WEST-TO-EAST AND ENERGY IMPULSES ARE FORECAST TO CONTINUE MOVING EASTWARD ACROSS NORTH DAKOTA TODAY. THE SURFACE TROUGH IS FORECAST TO MOVE EASTWARD ACROSS THE DAKOTAS TODAY AND REACH THE RED RIVER VALLEY LATER TONIGHT. THIS BOUNDARY WILL BE THE FOCUS OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA TODAY. SHOWERS AND ISOLATED THUNDERSTORMS THAT DEVELOPED SUNDAY EVENING CONTINUED THIS MORNING...WITH THE BEST INSTABILITY OVER THE WYOMING/SOUTH DAKOTA BORDER NEAR THE SURFACE LOW. HOWEVER THIS MORNING AN INSTABILITY AXIS (OF HIGHER MID LEVEL LAPSE RATES AND ELEVATED CAPE) EXTENDED FROM THE WY/SD BORDER ACROSS WESTERN NORTH DAKOTA. THIS COINCIDES WITH THE SURFACE TROUGH AND CONFIDENT THAT THE BEST CHANCES FOR CONVECTION TODAY WILL BE ALONG THE TROUGH. THE EASTWARD-MOVING UPPER LEVEL IMPULSES WILL ENHANCE THE CONVECTION AND HELP MOVE THE SHOWERS EASTWARD. TONIGHT...THE MODELS INDICATE THE CANADIAN LOW BEGINNING TO LIFT NORTHEASTWARD...AND KEEPING THE ASSOCIATED UPPER IMPULSES NORTH OF THE CANADIAN BORDER. HOWEVER...A DEVELOPING UPPER LEVEL TROUGH OVER THE ROCKIES DAYTIME MONDAY WILL APPROACH THE DAKOTAS TONIGHT AND BRING INCREASING CHANCES OF THUNDERSTORMS TONIGHT IN SOUTHWESTERN NORTH DAKOTA. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 413 AM CDT MON JUN 10 2013 MODELS OVERALL IN DECENT AGREEMENT REGARDING THE GENERAL SYNOPTIC PATTERN FOR THE LONG TERM FORECAST PERIOD. LARGER DIFFERENCES IN THE DETAILS FOR THE CURRENT 00Z MODEL SUITE COMPARED TO YESTERDAY. FORECAST HIGHLIGHTS IN THE EXTENDED PERIOD WILL BE CHANCES FOR SHOWERS/THUNDERSTORMS THROUGH THE WORK WEEK INTO NEXT WEEKEND. WILL SEE SOME PERIODS OF GREATER PRECIPITATION CHANCES AND COVERAGE...TUESDAY/TUESDAY NIGHT/WED MORNING AND AGAIN THURSDAY NIGHT THROUGH FRIDAY AFTERNOON/EVENING. UPPER LEVEL RIDGE BUILDS EAST ACROSS THE SOUTHERN PLAINS MONDAY NIGHT WITH LINGERING UPPER LEVEL LOW PRESSURE OVER SOUTH CENTRAL CANADA. MID LEVEL LOW PRESSURE CURRENTLY OFF THE SOUTHERN CALIFORNIA COAST IS STILL FORECAST TO EJECT NORTHEAST ACROSS THE ROCKIES AND INTO THE DAKOTAS...NOW ARRIVING TUESDAY NIGHT/EARLY WEDNESDAY. EARLIER MODEL RUNS HAD THIS FEATURE ARRIVING 6-12 HOURS FASTER. A FEW CHANGES TO DISCUSS FOR TUESDAY MORNING/AFTERNOON. THE LAST TWO RUNS OF THE ECMWF PAINT A BAND OF QPF ACROSS NORTHWEST NORTH DAKOTA WITH LIGHTER QPF OVER THE REST OF THE CWA. WHILE THE GFS IS DRY...THE NAM ALSO IS INDICATING PRECIPITATION. DISCOUNTED THE GFS FOR THIS PARTICULAR PERIOD AS IT APPEARS THERE WILL BE ENOUGH OVERRUNNING FLOW AND FORCING ALOFT IN THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET TO WARRANT MENTIONING PRECIPITATION. MUCH DEPENDS ON HOW FAR SOUTH SURFACE HIGH PRESSURE EXTENDS INTO THE REGION AND HOW FAR WEST AS WELL. THE GFS HAS A SURFACE RIDGE EXTENDING OVER ALL BUT THE SOUTHWEST...WHILE ECMWF IS A TAD MORE NORTH. THE SFC HIGH WILL LIMIT THUNDERSTORM CHANCES TUESDAY/TUESDAY NIGHT TO THE FAR SOUTH WITH LITTLE IF ANY INSTABILITY NORTH OF THE SD/ND BORDER COUNTIES. UPPER LEVEL RIDGE REBUILDS ACROSS THE NORTHERN PLAINS WEDNESDAY DAYTIME...WITH THE RIDGE AXIS PUSHING INTO THE CENTRAL DAKOTAS WEDNESDAY NIGHT/THURSDAY AHEAD OF A LONG WAVE TROUGH DEVELOPING OVER THE WEST COAST. SHOWERS ARE EXPECTED TO LINGER MAINLY SOUTH WED MORNING..WITH ISOLATED CONVECTION POSSIBLE WED AFTERNOON. MODELS HAVE DIVERGED FROM THEIR EARLIER AGREEMENT WITH SOUTHWEST FLOW ALOFT DEVELOPING OVER MY WEST. THE ECMWF HAS SLOWED DOWN WITH THE EASTWARD PROGRESSION OF THE RIDGE AXIS...WITH SOUTHWEST FLOW DEVELOPING NOT UNTIL THURSDAY DAYTIME. THE GFS STILL MAINTAINS FLOW ALOFT TRANSITIONING TO SOUTHWEST WED NIGHT. SCALED BACK POPS CENTRAL WED NIGHT BUT KEPT A MENTION OF NOCTURNAL THUNDERSTORMS WEST. WEST COAST TROUGH LIFTS INTO THE WYOMING/MONTANA ROCKIES BY 12Z FRIDAY...THEN EAST-NORTHEAST THROUGH THE NORTHERN PLAINS FRIDAY-FRIDAY NIGHT. ASSOCIATED SURFACE TROUGH IS STILL FORECAST TO MOVE INTO WESTERN NORTH DAKOTA 6-12Z FRIDAY MORNING...AND INTO EASTERN NORTH DAKOTA 00-06Z FRIDAY EVENING. THIS SUGGESTS HIGH CHANCES AND EXTENSIVE COVERAGE OF THUNDERSTORMS WEST LATE THURSDAY NIGHT DEVELOPING EAST FRIDAY MORNING/AFTERNOON WITH DECREASING CHANCES/COVERAGE FROM WEST TO EAST FRIDAY AFTERNOON INTO FRIDAY EVENING BEHIND THE SFC TROUGH AND UPPER LEVEL WAVE. WILL NEED TO MONITOR FOR STRONG TO SEVERE POSSIBILITY THIS PERIOD GIVEN THE FORCING AND INSTABILITY PARAMETERS. THE ALL-BLEND MODEL CONSENSUS MAINTAINS A SLIGHT CHANCE OF PRECIPITATION SATURDAY AND SUNDAY...BUT THE WEEKEND DOES NOT APPEAR TO BE A WASH-OUT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1252 PM CDT MON JUN 10 2013 VFR CONDITIONS WILL PREVAIL OVER WESTERN AND CENTRAL NORTH DAKOTA TONIGHT. MVFR VSBYS MAY DEVELOP OVER KJMS BETWEEN 09Z-13Z TUESDAY. FURTHERMORE...THERE WILL BE A CHANCE OF THUNDERSTORMS OVER SOUTHWESTERN NORTH DAKOTA (KDIK) AFTER 11Z TUESDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TM SHORT TERM...JV LONG TERM...NH AVIATION...TM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1250 PM CDT MON JUN 10 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 346 AM CDT MON JUN 10 2013 CLEAR SKIES/LIGHT WINDS AND RESIDUAL BOUNDARY LAYER MOISTURE FROM RECENT RAINS ALLOWING DENSE FOG TO DEVELOP IN WESTERN/CENTRAL PARTS OF THE CWA EARLY THIS MORNING. HRRR HAS LATCHED ONTO EXPANSION OF THE LOWEST VISIBILITIES WHICH HAS OCCURRED OVER THE PAST HOUR OR SO...AND IT SHOWS POTENTIAL FOR DENSE FOG PERSISTING IN THE SURFACE RIDGE AXIS THROUGH ABOUT 13-14Z WITH RAPID IMPROVEMENT THEREAFTER. ISSUED DENSE FOG ADVISORY DUE TO EXPECTED PERSISTENCE...THOUGH MAY STILL BE A BIT PATCHY IN SPOTS...ESPECIALLY THE FAR WEST WHERE THE WIND MAY PICK UP A BIT AS THE RIDGE SHIFTS EAST. STRATUS AND A BIT MORE WIND EAST OF THE RIDGE AXIS HAS HELPED TO HOLD VISIBILITY UP ACROSS NORTHWEST IOWA AND PARTS OF SOUTHWEST MN THUS FAR...SO DID NOT INCLUDE THEM IN THE ADVISORY AT THIS TIME...THOUGH WILL WATCH FOR DOWNWARD TREND SHOULD THE STRATUS CLEAR. SEEING SOME ACCAS STREAMING TOWARD FAR WESTERN COUNTIES EARLY THIS MORNING AS WELL. SOUTHERN EDGE HAS SHOWN TENDENCY TO DISSIPATE AS IT SHIFTS EAST... AND 06Z NAM INDICATES THIS TREND AS WELL...KEEPING BULK OF HIGHER MID LEVEL MOISTURE NORTH OF OUR CWA THROUGH THE MORNING. DID BRING IN A LITTLE HIGHER SKY COVER TO OUR NORTHWEST EARLY...BUT THINK MOST OF THE DAY SHOULD SEE FAIR AMOUNT OF SUNSHINE. THUS AFTER THE FOG BURNS OFF...EXPECT TEMPERATURES TO REBOUND NICELY...THOUGH PERHAPS A BIT MORE SLOWLY IN THE EAST WHERE STRATUS MAY LINGER INTO THE MID TO LATER MORNING HOURS. WITH 925MB TEMPERATURES FORECAST TO RISE INTO THE 20S C BY 11/00Z...HIGHS FROM THE UPPER 70S EAST TO THE MID-UPPER 80S SOUTHWEST LOOK GOOD. MID LEVEL CLOUDS WILL BE ON THE INCREASE MONDAY NIGHT AS ATMOSPHERE ABOVE 600 MB SATURATE IN RESPONSE TO INCREASE IN THETAE ADVECTION. WHILE SHORTWAVE IS EXPECTED TO MOVE ACROSS THE FORECAST AREA...APPEARS AS THOUGH ATMOSPHERE WILL REMAIN EFFECTIVELY CAPPED LIMITING THUNDERSTORM POTENTIAL TO FAR WESTERN PORTIONS OF CWA IN CENTRAL SOUTH DAKOTA. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 346 AM CDT MON JUN 10 2013 THE OUTSIDE CHANCE OF AN ELEVATED STORMS WILL CONTINUE THROUGH TUESDAY MORNING...BUT EXPECT CHANCES TO DWINDLE THROUGHOUT THE DAY ON TUESDAY. FORECAST AREA REMAINS IN EASTERLY FLOW THROUGHOUT THE DAY ON TUESDAY AS WARM FRONT LIFTS NORTH TOWARDS THE CWA. TOUGH CALL ON CONVECTION CHANCES TUESDAY NIGHT WITH STRONG MID LEVEL CAP PRESENT. MODELS HIND THAT CAP MAY TRY TO WEAKEN...AND THE BEST CHANCE FOR THUNDERSTORMS REMAINS ACROSS THE NORTHERN FRINGE OF THE FORECAST AREA. IF STORMS ARE ABLE TO DEVELOP...THEY WOULD LIKELY QUICKLY BECOME SEVERE PRODUCING SEVERE HAIL WITH STRONG MID LEVEL LAPSE RATES. HAVE LEFT LINGERING POPS INTO WEDNESDAY...THOUGH THERE IS REALLY A LACK OF ANY LARGE SCALE FOCUSING MECHANISM WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NORTH. AS SUCH...JUST HAVE A GENERAL 20-40 CHANCE WHICH WILL BE VERY DEPENDENT ON WHAT HAPPENS TUESDAY NIGHT. THURSDAY INTO THE BETTER PORTION OF FRIDAY SHOULD BE RELATIVELY DRY. THE EXCEPTION TO THIS WOULD BE LATE ON THURSDAY NIGHT AS WARM AIR ADVECTION INCREASES UNDER SOUTHERLY FLOW AND COULD SEE ACCAS SHOWERS. POTENTIAL FOR DEEP CONVECTION FRIDAY NIGHT CONTINUES TO INCREASE AS UPPER LEVEL LOW PRESSURE SYSTEM LIFTS NORTHEAST INTO CENTRAL CANADA AND TRAILING COLD FRONT MOVES ACROSS THE FORECAST AREA. WHAT CONTINUES TO BE IMPRESSIVE ABOUT THIS SET UP ARE THE VERY STEEP LAPSE RATE FROM 700-400 MB AND SPEED SHEAR ALOFT INDICATING THE POTENTIAL FOR VERY LARGE HAIL IF THUNDERSTORMS ARE ABLE TO DEVELOP. THE UNSETTLED PATTERN CONTINUES INTO THE WEEKEND AS UPPER LEVEL LOW RE-ESTABLISHES ITSELF OFF THE PACIFIC NW COAST. PIECES OF ENERGY PERIODICALLY BREAK OFF THE UPPER LEVEL LOW EJECTING INTO THE PLAINS. AT THIS POINT...IT CONTINUES TO BE DIFFICULT TO PINPOINT PRECISE TIMING OF DEEP CONVECTION...BUT HAVE STARTED TO TWEAK DAYTIME POPS DOWN AND NOCTURNAL POPS UP TO HELP ACCOUNT FOR TYPICAL DIURNAL PATTERN THIS TIME OF YEAR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1245 PM CDT MON JUN 10 2013 MVFR CIGS LINGERING ACROSS PORTIONS OF NORTHWEST IOWA AND SOUTHWEST MINNESOTA...WITH VFR CONDITIONS ELSEWHERE. CONDITIONS SHOULD BECOME VFR EVERYWHERE BY MID AFTERNOON. SOME INDICATIONS THAT SOME SHOWER AND THUNDERSTORM ACTIVITY COULD DEVELOP OVER THE WESTERN PLAINS THIS AFTERNOON AND EVENING AND MOVE TOWARDS US TONIGHT. THUS COULD SEE SOME HIGH BASED SHOWER OR THUNDERSTORM ACTIVITY AFTER MIDNIGHT INTO THE MORNING HOURS...BUT CONFIDENCE AND EXPECTED COVERAGE ARE BOTH TOO LOW TO MENTION IN THE TAFS AT THIS TIME. MOS GUIDANCE SUGGESTS WE COULD SEE SOME FOG TONIGHT....BUT THINK THE INCREASING MID LEVEL CLOUD COVER AND A LIGHT BREEZE WILL PROBABLY PREVENT THAT FROM HAPPENING...SO WILL LEAVE THAT OUT OF THE TAFS FOR NOW AS WELL. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...JH LONG TERM... AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
549 PM CDT MON JUN 10 2013 .AVIATION 00Z DISCUSSION... FRONTAL BOUNDARY TO CROSS THE REMAINDER OF THE MID STATE BY MID TO LATE EVENING. ISOLATED TO SCATTERED CONVECTION WILL BE POSSIBLE ALONG AND JUST AHEAD OF THE BOUNDARY. CONVECTION TO TERMINATE AT CSV BY 03Z. FOLLOWING THIS...SOME PATCHY FOG POSSIBLE CSV BY 12Z WITH VSBYS AS LOW AS 1SM...1-3SM POSSIBLE FOR CKV AND BNA. PLENTIFUL SUNSHINE FOR YOUR TUESDAY WITH JUST A FEW CLDS AT THE 4KFT LEVEL. && .PREV DISCUSSION... /ISSUED 440 PM CDT MON JUN 10 2013/ MESOSCALE UPDATE... RADAR INDICATING THAT THE FRONTAL BOUNDARY EXTENDS FROM SPRINGFIELD TN SW THROUGH DICKSON COUNTY. LAPS DATA STILL SHOWING ELEVATED HELICITY VALUES ALONG AND JUST AHEAD OF THE BOUNDARY. THUS...WILL DELAY CANCELLING ADDITIONAL WATCH AREAS UNTIL FRONTAL BOUNDARY MOVES EAST OF CURRENT WATCH COUNTIES. WITHIN THE PAST HOUR...SOME MINOR ROTATION WAS STILL INDICATED OVER OUR WESTERN COUNTIES. LATEST HRRR STILL REFRAINS FROM ADDITIONAL DEVELOPMENT BUT WILL STILL WAIT FOR THE FROPA AND WILL THEN COMMENCE WITH CANCELLATIONS. OTHERWISE...INTENSE STORMS OVER THE NORTHERN AND CENTRAL PLATEAU CONTINUES. THOUGH SLIGHTLY WEAKER...APPRECIABLE SHEAR STILL EXISTS OVER THE CURRENT WATCH AREA. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
440 PM CDT MON JUN 10 2013 .MESOSCALE UPDATE... RADAR INDICATING THAT THE FRONTAL BOUNDARY EXTENDS FROM SPRINGFIELD TN SW THROUGH DICKSON COUNTY. LAPS DATA STILL SHOWING ELEVATED HELICITY VALUES ALONG AND JUST AHEAD OF THE BOUNDARY. THUS...WILL DELAY CANCELLING ADDITIONAL WATCH AREAS UNTIL FRONTAL BOUNDARY MOVES EAST OF CURRENT WATCH COUNTIES. WITHIN THE PAST HOUR...SOME MINOR ROTATION WAS STILL INDICATED OVER OUR WESTERN COUNTIES. LATEST HRRR STILL REFRAINS FROM ADDITIONAL DEVELOPMENT BUT WILL STILL WAIT FOR THE FROPA AND WILL THEN COMMENCE WITH CANCELLATIONS. OTHERWISE...INTENSE STORMS OVER THE NORTHERN AND CENTRAL PLATEAU CONTINUES. THOUGH SLIGHTLY WEAKER...APPRECIABLE SHEAR STILL EXISTS OVER THE CURRENT WATCH AREA. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
309 PM CDT MON JUN 10 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 309 PM CDT MON JUN 10 2013 CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OVER SOUTHERN CALIFORNIA...SUBTROPICAL RIDGING OVER NEW MEXICO AND COLORADO AND WEAK RIDGING EXTENDING FROM THE SUBTROPICAL RIDGE INTO THE FORECAST AREA. ALSO OF NOTE IS A SHORTWAVE IN EASTERN NORTH DAKOTA RIDING THROUGH NEARLY ZONAL FLOW THERE. SUBSIDENCE UNDER THE WEAK RIDGING TRAPPED LOW LEVEL MOISTURE AS SEEN ON THE 12Z MPX/DVN SOUNDINGS...WITH SATURATION NEARLY UP TO 800MB BUT PLENTY OF DRYING ABOVE THAT. THE RESULT WAS EXPANSIVE STRATUS AND SOME FOG THIS MORNING. DAYTIME MIXING OVER THE PAST FEW HOURS HAS REALLY HELPED DISSIPATE THE STRATUS...THOUGH. AIRMASS OVER THE AREA WITH RESPECT TO WARMTH EXHIBITS 850MB TEMPS OF 10-13C PER 12Z RAOBS...WHICH ARE NEAR NORMAL. HOWEVER...UNDER THE SUBTROPICAL RIDGE...850MB TEMPS ARE 22-26C OR 1.5-2 STANDARD DEVIATIONS ABOVE NORMAL. 700MB TEMPS ARE ALSO QUITE WARM...RANGING FROM 14-17C FROM RAPID CITY AND AMARILLO WEST TO SALT LAKE CITY. TO OUR NORTHWEST...SCATTERED SHOWERS AND STORMS HAVE BEEN GOING ALL DAY OVER NORTHEAST NORTH DAKOTA...AHEAD OF THE SHORTWAVE THERE. THE SUBTROPICAL RIDGING IN NEW MEXICO AND COLORADO IS PROGGED TO SHIFT EAST INTO THE CENTRAL PLAINS ON TUESDAY...PUSHED EAST BY THE UPPER LOW IN SOUTHERN CALIFORNIA LIFTING AND SHEARING OUT INTO WYOMING BY 00Z WEDNESDAY. THIS MEANS ALL THE WARM AIR OVER THE ROCKIES WILL SPILL EAST AND TRY TO HEAD TOWARDS THE FORECAST AREA. MEANWHILE...UPPER TROUGHING OVER SOUTH CENTRAL CANADA IS FORECAST TO DROP INTO THE EASTERN GREAT LAKES ON TUESDAY...PROVIDING SOME BLOCKING TO THE WARM AIR. AS A RESULT...WHILE 850MB TEMPS CLIMB BY 00Z WEDNESDAY TO 14C NORTH TO 18C SOUTH ACROSS THE FORECAST AREA...READINGS OF 24-36C LOOK COMMON ACROSS MUCH OF NEBRASKA AND KANSAS. NEVERTHELESS...A MUCH WARMER DAY LOOKS ON TAP FOR TUESDAY. IF WE CAN MIX UP TO THE AFOREMENTIONED 850MB TEMPS...READINGS WOULD TOP OUT IN THE UPPER 70S TO MID 80S...TEMPERATURES SOME LOCATIONS HAVE NOT SEEN SINCE MID MAY. WITH THE WARMER AIR COMING AT US...THERE IS ALWAYS A CONCERN FOR ELEVATED CONVECTION. TONIGHT APPEARS DRY WITH THE BULK OF MOISTURE TRANSPORT FROM 925MB TO 700MB ALL FOCUSED WEST OF THE AREA. IN FACT...MUCH OF THE NIGHT SHOULD BE CLEAR WITH THE CURRENT CLOUDS DISSIPATING WITH DIURNAL COOLING GIVEN THEIR NOW CELLULAR NATURE. ON TUESDAY...THAT SHORTWAVE CURRENTLY IN EASTERN NORTH DAKOTA IS PROGGED TO BYPASS US TO THE NORTH...ALONG WITH ITS RELATED SHOWER/THUNDERSTORM ACTIVITY. HOWEVER...THERE ARE INDICATIONS OF SOME VERY HIGH BASED SHOWERS AND POSSIBLY EVEN THUNDERSTORMS FROM THE 10.06Z/12Z NAM...10.06Z HIRES ARW AND 10.12Z REGIONAL CANADIAN ALL CROSSING THE FORECAST AREA DURING THE AFTERNOON HOURS. THESE APPEAR TO COME OUT OF THE DAKOTAS TONIGHT ON THE LEADING EDGE OF SOME 700MB MOISTURE TRANSPORT. GIVEN THE GOOD MODEL AGREEMENT...HAVE INCREASED CLOUD COVER AND ADDED 20 PERCENT CHANCES FOR SHOWERS AND THUNDERSTORMS. DID NOT GO ANY HIGHER WITH THE CHANCES BECAUSE OF DRY AIR BELOW 700MB LIKELY ABSORBING SOME OF THE RAIN. THE CLOUDS WILL HAMPER TEMPERATURES FROM CLIMBING TO THEIR FULL MIXING VALUES MENTIONED EARLIER. LASTLY...FOG POTENTIAL TONIGHT. SKIES CLEARING LATE IN THE DAY... LIGHT WINDS FOR MUCH OF THE NIGHT AND MOIST SOILS ARE ALL VERY FAVORABLE FOR FOG. THIS LOOKS ESPECIALLY TRUE IN VALLEYS WHERE EVAPOTRANSPORATION OF MOISTURE CAN POOL. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 309 PM CDT MON JUN 10 2013 MAIN FOCUS CONTINUES TO BE ON THE POTENTIAL FOR SEVERE WEATHER...AND IN GENERAL PRECIPITATION CHANCES...FROM TUESDAY NIGHT INTO WEDNESDAY EVENING. THE FORECAST IS PROBLEMATIC DURING THE TUESDAY NIGHT INTO WEDNESDAY PERIOD...PRIMARILY RELATED TO ALL THE WARM AIR COMING OUT INTO THE PLAINS THE NEXT 24 HOURS. SYNOPTICALLY...THE MAIN FEATURE TO LOCK ONTO IS THE SHEARING OUT UPPER LOW OVER WYOMING AT 00Z WEDNESDAY... WHICH MODELS ARE IN REALLY GOOD AGREEMENT TRACKING INTO CENTRAL SOUTH DAKOTA BY 12Z WEDNESDAY AND THEN INTO CENTRAL IOWA BY 00Z THURSDAY. MODELS ARE ALSO IN VERY GOOD AGREEMENT OF THUNDERSTORMS DEVELOPING IN WESTERN SOUTH DAKOTA TUESDAY EVENING AS THE POTENT SHORTWAVE MOVES IN THERE. USING THE 10.12Z MODEL RUNS AS WELL AS PAST MODELS...A COUPLE OF SCENARIOS CAN PLAY OUT: 1. THERE ARE SOME INDICATIONS OF A WEAK SHORTWAVE COMING OUT OF EASTERN COLORADO AND LIFTING TO THE SIOUX FALLS AREA BY 06Z WEDNESDAY. THERE HAVE BEEN VARIOUS MODEL RUNS SUGGESTING THIS WILL HELP BREAK THE CAPPING PRESENT BETWEEN 650-700MB...RESULTING IN AN MCS WHICH THEN CORFIDI VECTORS WOULD BRING INTO SOUTHERN PORTIONS OF THE FORECAST AREA BETWEEN 06-15Z WEDNESDAY. THE MCS COULD BE A BOW ECHO. THE 10.06Z/12Z HI RES ARW MODELS...WHICH ARE TYPICALLY GOOD STORM SCALE MODEL FORECASTS...HINT AT THIS SCENARIO. 2. SOME SCATTERED SHOWERS/STORMS FIRE THROUGH TUESDAY NIGHT... ESPECIALLY AFTER MIDNIGHT ON THE LEADING EDGE OF THE CAPPING. HOWEVER...NONE OF THESE ORGANIZE INTO AN MCS AS IN SCENARIO 1 WHICH WOULD LIMIT SEVERE POTENTIAL. THE 10.12Z REGIONAL CANADIAN SUGGESTS THIS SCENARIO. 3. NOTHING HAPPENS OR MAYBE ISOLATED STORMS AT BEST TUESDAY NIGHT LIKE THE 10.12Z ECMWF...AND WE HAVE 1 OR 2 ROUNDS OF SHOWERS AND THUNDERSTORMS AS THE POTENT SHORTWAVE HEADING INTO IOWA LATE IN THE DAY MOVES IN. SO FOR THE TUESDAY NIGHT/WEDNESDAY FORECAST...HAVE LOWERED PRECIPITATION CHANCES FURTHER TUESDAY EVENING WHICH COULD EVEN END UP DRY. AFTER MIDNIGHT...KEPT THE HIGHER CHANCES OF 60-70 GOING PER SCENARIOS 1 AND 2...AND DID SHIFT THEM NORTH TO COME INTO BETTER CONSENSUS. ALL 3 ABOVE SCENARIOS SUGGEST THE SECOND PART OF SCENARIO 3 IS TRUE...WHERE POTENTIAL FOR 1 OR 2 ROUNDS OF SHOWERS AND THUNDERSTORMS MOVES ACROSS THROUGH THE DAY. IN FACT...THE AFTERNOON INTO THE EVENING HOURS ALMOST LOOK LIKE FRONTOGENESIS NORTH OF A SURFACE LOW WHICH IS TRACKING ACROSS SOUTHERN IOWA...I.E. A MORE WINTER/SPRING LIKE APPEARANCE. THUS...RAISED PRECIPITATION CHANCES WEDNESDAY AFTERNOON AND SHIFTED THE CHANCES FARTHER NORTH TO COME INTO THE MODEL CONSENSUS. ALSO ENDED UP COOLING HIGHS ON WEDNESDAY WITH POTENTIAL FOR MULTIPLE ROUNDS OF RAIN. THESE MAY NEED TO BE COOLED FURTHER. AFTER 06Z THURSDAY AND GOING THROUGH THE REST OF THE DAY THURSDAY... THE FORECAST GETS EASIER. HIGH AMPLITUDE UPPER RIDGING IS PROGGED TO BUILD UP THROUGH THE PLAINS AHEAD OF A DEEP TROUGH FORMING OVER THE PACIFIC NORTHWEST. NORTHWEST FLOW DOWN THE UPPER RIDGE WILL HELP KICK THE SHORTWAVE OVER CENTRAL IOWA AT 00Z THURSDAY SOUTHEASTWARD...ALLOWING HIGH PRESSURE TO BUILD IN AND DRYING TO OCCUR. THE NORTHWEST FLOW ALSO SENDS 850MB TEMPS DOWNWARD TO 10-12C BY 18Z THURSDAY...THUS EXPECT COOLER BUT SEASONABLE WEATHER FOR THURSDAY. THURSDAY NIGHT THROUGH MONDAY... 10.12Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES CONTINUE TO SHOW THAT THE DEEP PACIFIC NORTHWEST TROUGH IS GOING TO EJECT OUT ON FRIDAY WHILE NEW TROUGHING REFORMS OFF THE PACIFIC NORTHWEST. AS THAT PACIFIC NORTHWEST TROUGH LIFTS NORTHEASTWARD...IT PUSHES AND FLATTENS THE AMPLIFIED RIDGE TOWARDS US. HIGH PRESSURE AHEAD OF THE RIDGE SHOULD HELP KEEP THURSDAY NIGHT AND FRIDAY DRY...WITH ANY CONVECTION GOING UP WELL TO THE WEST OVER THE DAKOTAS AND WESTERN IA IN THE WARM ADVECTION ZONE. HEADING INTO FRIDAY NIGHT AND SATURDAY...THAT WARM ADVECTION ZONE SHIFTS EAST WHICH WOULD PUSH THE THREAT FOR CONVECTION INTO US. CONSENSUS CHANCES OF 60 WEST TO 20 EAST FRIDAY NIGHT AND 30-40 FOR SATURDAY SEEM REASONABLE. HOWEVER...THERE IS GROWING AGREEMENT AMONGST MODELS OF AN MCS TO FORM FRIDAY NIGHT OVER WESTERN IOWA...WHICH THEN DIVES SOUTHEAST ON SATURDAY. IF THIS INDEED HAPPENS...THE PRECIPITATION CHANCES OVER US COULD BE GREATLY REDUCED AS THE MCS TRAPS ANY MOISTURE TRANSPORT TOWARDS US. BEYOND SATURDAY...A LOT OF UNCERTAINTY EXISTS WITH HANDLING OF THAT EJECTING PACIFIC NORTHWEST TROUGH. THERE ARE SOME SUGGESTIONS OF A COLD FRONT ASSOCIATED WITH IT APPROACHING THE AREA ON SUNDAY PER 10.12Z CANADIAN/GFS...WHICH WOULD REQUIRE CHANCES FOR SHOWERS AND THUNDERSTORMS...WHILE THE 10.12Z ECMWF STILL HAS THAT FRONT BACK IN THE DAKOTAS KEEPING THE AREA DRY. THESE TWO MODEL GROUPS BECOME REVERSED FOR SUNDAY NIGHT AND MONDAY WITH THE ECMWF BRINGING THE FRONT IN AND THE CANADIAN/GFS HAVING IT SOUTH OF US. THUS...BOTH SUNDAY AND MONDAY FEATURE 20-30 PERCENT CHANCES OF SHOWERS AND THUNDERSTORMS. TEMPERATURES OVERALL LOOK AROUND NORMAL WITH NO SIGNIFICANT WARM UP OR COOL DOWN BEING IN A MEAN NORTHWEST TO WEST-NORTHWEST FLOW ALOFT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1215 PM CDT MON JUN 10 2013 DIURNAL WARMING/MIXING AND INFLUX OF SOME DRIER AIR SLOWLY LIFTING/ ERODING THE LOWER CLOUD DECKS OVER THE FCST AREA THRU THE MORNING. WITH RATHER LIGHT SFC-700MB GRADIENT WINDS...THIS PROCESS SLOW... WITH SOME VFR/MVFR STRATO-CU CIGS LOOKING TO LINGER INTO THE MID AFTERNOON HOURS. SFC-850MB RIDGE OF HIGH RIDGE OF HIGH PRESSURE TO DRIFT EAST ACROSS THE AREA TONIGHT. DIVERGENCE/SUBSIDENCE IN THIS RIDGE AXIS EXPECTED TO CONTINUE DECREASING THE STRATO-CU WITH SKIES BECOMING CLEAR THIS EVENING. SFC RIDGE AXIS...LIGHT WINDS/ LEAR SKIES AND THE MOIST BOUNDARY LAYER...SOME RADIATIONAL BR WITH MVFR VSBYS EXPECTED TO FORM LATE TONIGHT/EARLY TUE MORNING. WILL HAVE TO WATCH THIS FOR THE DECREASE OF CLOUDS BY LATER THIS AFTERNOON/EARLY THIS EVENING. IF THE CLEARING IS DELAYED UNTIL LATE IN THE DAY... AREA OF IFR VSBYS IN BR/FG POSSIBLE ACROSS THE FCST AREA... ESPECIALLY IN THE MS AND LOWER WI RIVER VALLEYS. VFR CONDITION EXPECTED TUE ONCE ANY BR/FG WOULD BURN OFF IN THE MORNING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1232 PM CDT MON JUN 10 2013 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 424 AM CDT MON JUN 10 2013 WV IMAGERY AND RAP ANALYSIS SHOWED AN UPPER LOW WEAKENING AS IT MOVED ESE INTO CENTRAL IL. SCATTERED SHOWERS ASSOCIATED WITH ITS DEFORMATION ZONE WERE ATTEMPTING TO WRAP BACK INTO OUR FAR SE COUNTIES...BUT WERE DISSIPATING. STRONG ZONAL FLOW ALOFT WAS IN PLACE FROM THE PACIFIC NW THROUGH MINNESOTA...WITH A WELL-DEFINED S/W TROF AND 110 KT JET STREAK MOVG ALONG THE NORTH DAKOTA/CANADIAN BORDER. THIS ENERGY APPEARED POISED TO CLIP NORTHERN WI LATER TODAY. CLOUDS HAD SCATTERED OUT OVER MUCH OF GRB EARLY THIS MORNING...AND PATCHY FOG WAS DEVELOPING. PATCHY FOG SHOULD DISSIPATE QUICKLY BY MID-MORNING. SHOWERS ASSOCIATED WITH THE DEPARTING UPPER SYSTEM ARE NOT EXPECTED TO MAKE IT INTO OUR FAR SE COUNTIES EARLY TODAY...SO WILL NOT MENTION. S/W TROF AND JET STREAK MOVG RAPIDLY THROUGH ND AND NW MN SHOULD MOVE INTO N WI LATE THIS MORNING AND AFTERNOON...AND COMBINE WITH DAYTIME HEATING AND WEAK LOW-LEVEL CONVERGENCE TO PRODUCE SCT SHOWERS OVER MUCH OF THE FA. THE SHOWERS ARE EXPECTED TO MOST NUMEROUS OVER NC/FAR NE WI...WHERE FORCING AND INSTABILITY (CAPE 300-400 J/KG) IS EXPECTED TO BE GREATEST. HAVE INCLUDED A MENTION OF ISOLD TSTMS OVER THE FAR NORTH. CONSIDERED GOING WITH LIKELY POPS OVER NORTHERN WI...BUT OPTED FOR HIGH CHANCE POPS INSTEAD...AS THE 00Z ECMWF CAME IN WITH MUCH LESS QPF THAN ITS PREVIOUS RUN. MIXING THROUGH 875-850 MB SUPPORTS HIGH TEMPS IN THE MIDDLE 70S AWAY FROM LAKE MICHIGAN. GENERALLY DRY CONDITIONS ARE EXPECTED ACROSS THE REGION TONIGHT... WITH LIGHT WINDS AND PARTLY CLOUDY SKIES LEADING TO SOME FOG DEVELOPMENT OVERNIGHT. EXPECT A MILD NIGHT...WITH MIN TEMPS IN THE 50S. ON TUESDAY...ADDITIONAL SHORT-WAVE AND JET ENERGY WILL SKIM BY TO OUR NORTH AS A WEAK/SHALLOW COLD FRONT DROPS INTO THE REGION. HAVE CONTINUED WITH LOW POPS OVER NORTHERN WI...BUT POPS MAY NEED TO BE EXPANDED OVER MORE OF THE FORECAST AREA WITH SUBSEQUENT FCSTS. MIXING THROUGH 850-800 MB SUPPORTS A WARM DAY...WITH HIGHS IN THE LOWER 80S. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 424 AM CDT MON JUN 10 2013 MODEL GUIDANCE CONTINUED TO FOCUS ON A MORE SOUTHERLY SOLUTION FOR AN APPROACHING SHORT WAVE...SURFACE LOW PRESSURE SYSTEM AND ASSOCIATED FRONTAL BOUNDARY FOR TUESDAY NIGHT AND WEDNESDAY. HAVE GONE WITH A CHANCE OF SHOWERS AND THUNDERSTORMS FOR PARTS OF CENTRAL AND EAST CENTRAL WISCONSIN AND LEFT THE NORTH DRY BECAUSE OF THIS. SURFACE HIGH PRESSURE AND AN UPPER LEVEL RIDGE ACROSS THE CENTRAL CONUS SHOULD KEEP THURSDAY AND FRIDAY DRY...BEFORE THE NEXT SHORT WAVE AND AN APPROACHING COLD FRONT BRING A CHANCE OF SHOWERS AND THUNDERSTORMS BACK TO THE AREA FOR FRIDAY NIGHT AND SATURDAY. PRECIPITATION MAY LINGER INTO SUNDAY SO HAVE LEFT SOME CHANCE POPS IN FOR SATURDAY NIGHT AND SUNDAY AS WELL. TEMPERATURES SHOULD BE WITHIN A FEW DEGREES OF NORMAL FOR MOST OF THE FORECAST PERIOD. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1232 PM CDT MON JUN 10 2013 MVFR/VFR CU FIELD FILLING IN OVER CNTRL WI WHERE CLEARING HAD TAKEN PLACE EARLIER IN THE DAY. EXPECT THESE CLOUD BASES TO RISE INTO THE 3-4K RANGE THIS AFTERNOON BEFORE GRADUALLY DISSIPATING THIS EVENING WITH THE LOSS OF DAYTIME HEATING. A STRATOCU FIELD LOCKED OVER ERN WI FOR MOST OF THE DAY SHOULD BEGIN TO MIX OUT AS AN AREA OF LOW PRES OVER SW LWR MI PULLS FARTHER AWAY. STILL CANNOT RULE OUT A FEW SHWRS SOMEWHERE OVER NE WI AS DEW PTS ARE AROUND 60 DEGS. NE WI TO THEN SIT BETWEEN SYSTEMS TNGT WITH SKIES ATTEMPTING TO CLEAR. IF THIS DOES HAPPEN WITH LIGHT WIND/MOIST BOUNDARY LAYER REGIME...FOG WL DEVELOP AND POTENTIALLY LOWER VSBYS TO AT LEAST MVFR CONDITIONS AND LOCALLY IFR CIGS. EXPECT THIS FOG TO BURN OFF BY MID-MORNING TUE WITH VFR CONDITIONS RETURNING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....KIECKBUSCH LONG TERM......MG AVIATION.......AK