Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/25/13


AREA FORECAST DISCUSSION
NWS PUEBLO CO
454 PM MDT SUN JUN 23 2013 .UPDATE... ISSUED AT 447 PM MDT SUN JUN 23 2013 UPDATED TO ISSUE A SEVERE THUNDERSTORM WATCH FOR AREAS EAST OF A LINE FROM COLORADO SPRINGS TO SPRINGFIELD. THIS WATCH GOES THROUGH MIDNIGHT. THE MAIN THREATS WILL BE LIGHTNING...DAMAGING OUTFLOW WIND GUSTS AND HAIL TO ONE INCH IN DIAMETER. MOZLEY && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 227 PM MDT SUN JUN 23 2013 ...CONTINUED DANGEROUS FIRE WEATHER CONDITIONS... CURRENTLY...SMOKE FROM THE WEST FORK COMPLEX IS STARTING TO SHIFT EAST ACROSS THE SAN LUIS VALLEY AND SHOULD CONTINUE TO PUSH EAST THROUGH THE EVENING. RADAR HAS BEEN PRETTY QUIET WITH A FEW CELLS BUBBLING NEAR THE SPANISH PEAKS/WALSENBURG AREA. SOUTHEASTERLY SURFACE FLOW HAS KEPT MOISTURE IN PLACE ACROSS THE PLAINS WITH DEW POINTS IN THE 40S TO MID 50S. TEMPERATURES ARE WARM WITH UPPER 80S TO LOWER 90S FOR THE LOWER ELEVATIONS. TONIGHT...MAIN CONCERN FOR THIS EVENING WILL BE THE POTENTIAL FOR SEVERE THUNDERSTORMS ACROSS THE PLAINS. CUMULUS HAVE BEEN PERCOLATING ACROSS THE RAMPART RANGE AND EASTERN MOUNTAINS THIS AFTERNOON AND AS AN UPPER LEVEL DISTURBANCE MOVES THROUGH THE SOUTHWEST FLOW ALOFT...IT WILL LIKELY TRIGGER ISOLATED THUNDERSTORMS. FOLLOWED A BLEND OF THE WRF SOLUTIONS AND HRRR WHICH DEVELOP SPOTTY CONVECTION FROM COLORADO SPRINGS...SOUTHEAST TO SPRINGFIELD AND TRACK THEM EAST ACROSS THE PLAINS THROUGH 05Z. UPDRAFT HELICITY VALUES ARE WEAK BASED ON THE NSSL WRF SOLUTION AND SHEARS ARE ONLY RUNNING AROUND 30 KTS SO CURRENTLY THINKING THE MAIN THREATS WILL BE HAIL TO ONE INCH IN DIAMETER AND STRONG THUNDERSTORM OUTFLOW WINDS. THE TORNADO THREAT LOOKS TO REMAIN NORTH IN NORTHEAST COLORADO. EXPECT ALL ACTIVITY TO SHIFT EAST INTO KANSAS THROUGH 06Z WITH DRY CONDITIONS THE REST OF THE NIGHT. MONDAY...AN UPPER TROUGH WILL MOVE OUT OF THE PACIFIC NORTHWEST WHICH WILL INCREASE SOUTHWESTERLY FLOW ACROSS COLORADO. THIS WILL SET THE STAGE FOR WIDESPREAD EXTREME FIRE WEATHER CONDITIONS WITH WINDS GUSTING TO 30 TO 40 MPH...AND HUMIDITY VALUES WELL UNDER 10 PERCENT. EXTREME CAUTION IS ADVISED ACROSS ALL OF SOUTHERN COLORADO...BUT PARTICULARLY OVER THE MOUNTAIN REGIONS AND AREAS ALONG AND WEST OF I-25. THE STRONG WINDS SHOULD ALSO ALLOW TEMPERATURES TO WARM QUICKLY INTO TO THE UPPER 90S TO LOWER 100S ACROSS THE PLAINS. SMOKE FROM AREA FIRES WILL SPREAD ACROSS MUCH OF THE AREA BY THE AFTERNOON WITH REDUCED VISIBILITIES AND POOR AIR QUALITY. MOZLEY .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 227 PM MDT SUN JUN 23 2013 THERE COULD BE A FEW SHOWERS/TSTMS ALONG THE ERN BORDER EARLY MON EVENING...BUT WL LEAVE THE FORECAST DRY OUT THERE FOR NOW. DRY WESTERLY FLOW IS EXPECTED OVR THE FORECAST AREA ON TUE. IT LOOKS LIKE LOW LEVEL MSTR OVR THE ERN SAN JUAN AND LA GARITA MTNS MAY BE A LITTLE HIGHER ON TUE...KEEPING MIN RH VALUES HIGH ENOUGH THAT A FIRE WX HIGHLIGHT SHOULD NOT BE NEEDED FOR THAT AREA. HOWEVER THERE IS A CHANCE THAT THE WINDS WL BE STRONG ENOUGH...ALONG WITH DRY ENOUGH HUMIDITIES OVER THE SAN LUIS VALLEY (FIRE ZONE 224) AND ALONG THE SANGRE DE CRISTO MTNS (FIRE ZONE 225)...TO WARRANT A FIRE WEATHER WATCH. THE REST OF THE AREA SHOULD NOT HAVE STRONG ENOUGH WINDS TO WARRANT A FIRE HIGHLIGHT. FOR WED AN UPR RIDGE CENTER IS EXPECTED TO BE OVR THE WEST CENTRAL NM...WITH THE FLOW ALOFT OVR THE FORECAST AREA BECOMING MORE NORTHWESTERLY. STILL LOOKS DRY ACRS THE AREA...WITH MAYBE JUST A COUPLE SHOWERS/TSTMS POPPING UP OVR SOME MTN LOCATIONS. THE UPR RIDGE THEN REMAINS OVR THE AREA THU THRU SAT WITH MODELS INDICATING SOME MSTR TRAPPED UNDER THE RIDGE AND THE POTENTIAL FOR JUST A FEW SHOWERS/TSTMS OVR AND NR THE MTNS. THE GFS SHOWS THE POTENTIAL FOR A WEATHER SYSTEM MOVING BY TO THE NORTH SAT NIGHT/SUN FLATTENING THE RIDGE AND SENDING A FRONT INTO THE AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 227 PM MDT SUN JUN 23 2013 VFR CONDITIONS AT ALL TERMINALS THROUGH THE NEXT 24 HOURS. WINDS GUSTING 20 TO 25 KTS HAVE SPREAD ACROSS ALL TERMINALS. SMOKE IS STARTING TO SPREAD EAST OVER THE SAN LUIS VALLEY...BUT THE LATE START HAS KEPT THE DENSITY AND COVERAGE A BIT LESS AND DO NOT FORESEE IT BEING AN ISSUE AT KPUB OR KCOS TONIGHT. AN ISOLATED THUNDERSTORM IS POSSIBLE OVER THE PLAINS THIS EVENING...BUT NOT ANTICIPATING ANY DEVELOPMENT AT OR NEAR THE TERMINALS. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR COZ220>230. RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ223>225. FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR COZ224-225. && $$ UPDATE...MOZLEY SHORT TERM...MOZLEY LONG TERM...28 AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PUEBLO CO
251 PM MDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 227 PM MDT SUN JUN 23 2013 ...CONTINUED DANGEROUS FIRE WEATHER CONDITIONS... CURRENTLY...SMOKE FROM THE WEST FORK COMPLEX IS STARTING TO SHIFT EAST ACROSS THE SAN LUIS VALLEY AND SHOULD CONTINUE TO PUSH EAST THROUGH THE EVENING. RADAR HAS BEEN PRETTY QUIET WITH A FEW CELLS BUBBLING NEAR THE SPANISH PEAKS/WALSENBURG AREA. SOUTHEASTERLY SURFACE FLOW HAS KEPT MOISTURE IN PLACE ACROSS THE PLAINS WITH DEW POINTS IN THE 40S TO MID 50S. TEMPERATURES ARE WARM WITH UPPER 80S TO LOWER 90S FOR THE LOWER ELEVATIONS. TONIGHT...MAIN CONCERN FOR THIS EVENING WILL BE THE POTENTIAL FOR SEVERE THUNDERSTORMS ACROSS THE PLAINS. CUMULUS HAVE BEEN PERCOLATING ACROSS THE RAMPART RANGE AND EASTERN MOUNTAINS THIS AFTERNOON AND AS AN UPPER LEVEL DISTURBANCE MOVES THROUGH THE SOUTHWEST FLOW ALOFT...IT WILL LIKELY TRIGGER ISOLATED THUNDERSTORMS. FOLLOWED A BLEND OF THE WRF SOLUTIONS AND HRRR WHICH DEVELOP SPOTTY CONVECTION FROM COLORADO SPRINGS...SOUTHEAST TO SPRINGFIELD AND TRACK THEM EAST ACROSS THE PLAINS THROUGH 05Z. UPDRAFT HELICITY VALUES ARE WEAK BASED ON THE NSSL WRF SOLUTION AND SHEARS ARE ONLY RUNNING AROUND 30 KTS SO CURRENTLY THINKING THE MAIN THREATS WILL BE HAIL TO ONE INCH IN DIAMETER AND STRONG THUNDERSTORM OUTFLOW WINDS. THE TORNADO THREAT LOOKS TO REMAIN NORTH IN NORTHEAST COLORADO. EXPECT ALL ACTIVITY TO SHIFT EAST INTO KANSAS THROUGH 06Z WITH DRY CONDITIONS THE REST OF THE NIGHT. MONDAY...AN UPPER TROUGH WILL MOVE OUT OF THE PACIFIC NORTHWEST WHICH WILL INCREASE SOUTHWESTERLY FLOW ACROSS COLORADO. THIS WILL SET THE STAGE FOR WIDESPREAD EXTREME FIRE WEATHER CONDITIONS WITH WINDS GUSTING TO 30 TO 40 MPH...AND HUMIDITY VALUES WELL UNDER 10 PERCENT. EXTREME CAUTION IS ADVISED ACROSS ALL OF SOUTHERN COLORADO...BUT PARTICULARLY OVER THE MOUNTAIN REGIONS AND AREAS ALONG AND WEST OF I-25. THE STRONG WINDS SHOULD ALSO ALLOW TEMPERATURES TO WARM QUICKLY INTO TO THE UPPER 90S TO LOWER 100S ACROSS THE PLAINS. SMOKE FROM AREA FIRES WILL SPREAD ACROSS MUCH OF THE AREA BY THE AFTERNOON WITH REDUCED VISIBILITIES AND POOR AIR QUALITY. MOZLEY .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 227 PM MDT SUN JUN 23 2013 THERE COULD BE A FEW SHOWERS/TSTMS ALONG THE ERN BORDER EARLY MON EVENING...BUT WL LEAVE THE FORECAST DRY OUT THERE FOR NOW. DRY WESTERLY FLOW IS EXPECTED OVR THE FORECAST AREA ON TUE. IT LOOKS LIKE LOW LEVEL MSTR OVR THE ERN SAN JUAN AND LA GARITA MTNS MAY BE A LITTLE HIGHER ON TUE...KEEPING MIN RH VALUES HIGH ENOUGH THAT A FIRE WX HIGHLIGHT SHOULD NOT BE NEEDED FOR THAT AREA. HOWEVER THERE IS A CHANCE THAT THE WINDS WL BE STRONG ENOUGH...ALONG WITH DRY ENOUGH HUMIDITIES OVER THE SAN LUIS VALLEY (FIRE ZONE 224) AND ALONG THE SANGRE DE CRISTO MTNS (FIRE ZONE 225)...TO WARRANT A FIRE WEATHER WATCH. THE REST OF THE AREA SHOULD NOT HAVE STRONG ENOUGH WINDS TO WARRANT A FIRE HIGHLIGHT. FOR WED AN UPR RIDGE CENTER IS EXPECTED TO BE OVR THE WEST CENTRAL NM...WITH THE FLOW ALOFT OVR THE FORECAST AREA BECOMING MORE NORTHWESTERLY. STILL LOOKS DRY ACRS THE AREA...WITH MAYBE JUST A COUPLE SHOWERS/TSTMS POPPING UP OVR SOME MTN LOCATIONS. THE UPR RIDGE THEN REMAINS OVR THE AREA THU THRU SAT WITH MODELS INDICATING SOME MSTR TRAPPED UNDER THE RIDGE AND THE POTENTIAL FOR JUST A FEW SHOWERS/TSTMS OVR AND NR THE MTNS. THE GFS SHOWS THE POTENTIAL FOR A WEATHER SYSTEM MOVING BY TO THE NORTH SAT NIGHT/SUN FLATTENING THE RIDGE AND SENDING A FRONT INTO THE AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 227 PM MDT SUN JUN 23 2013 VFR CONDITIONS AT ALL TERMINALS THROUGH THE NEXT 24 HOURS. WINDS GUSTING 20 TO 25 KTS HAVE SPREAD ACROSS ALL TERMINALS. SMOKE IS STARTING TO SPREAD EAST OVER THE SAN LUIS VALLEY...BUT THE LATE START HAS KEPT THE DENSITY AND COVERAGE A BIT LESS AND DO NOT FORESEE IT BEING AN ISSUE AT KPUB OR KCOS TONIGHT. AN ISOLATED THUNDERSTORM IS POSSIBLE OVER THE PLAINS THIS EVENING...BUT NOT ANTICIPATING ANY DEVELOPMENT AT OR NEAR THE TERMINALS. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR COZ220>230. RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ223>225. FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR COZ224-225. && $$ SHORT TERM...MOZLEY LONG TERM...28 AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS ALBANY NY
145 PM EDT SUN JUN 23 2013 .SYNOPSIS... A WARM AND HUMID AIR MASS WILL CONTINUE THIS AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING THE NEXT FEW DAYS. SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE...AND PATCHY FOG WILL BE COMMON WITH MUGGY CONDITIONS EACH NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 130 PM EDT...CONVECTION HAS INITIATED ALONG THE DIFFUSE FRONTAL BOUNDARY ACROSS NORTHERN NY AND WESTWARD ALONG THE LAKE BREEZE BOUNDARY AND INTO THE FINGER LAKES REGION. EXPERIMENTAL WRF REFLECTIVITIES SUGGEST MORE UPSCALE GROWTH TO CONTINUE AS SBCAPES PER LAPS/SPC-MESOSCALE WINDOW ARE CLOSE TO 3K J/KG. IN FACT...SPC HAS INCREASED OUR PROBABILITIES INTO A SLIGHT RISK FOR SEVERE WEATHER WITH THE RECENT SWOMCD HINTING AT THE POTENTIAL FOR A WATCH. BEST SHEAR REMAINS MAINLY TO OUR NORTH AND MID LEVEL LAPSE RATES REMAIN LESS THAN IDEAL FOR VIGOROUS UPDRAFTS...HOWEVER...WITH DEWPOINTS NOW HOVERING NEAR 70F AND TEMPS NEAR 90F THE ENVIRONMENT IS CONDUCIVE FOR CELLULAR STRUCTURES AND/OR SMALL BOWS ALONG THE COLD POOL THAT IS GENERATED. AS OF 1026 AM EDT...A DIFFUSE FRONTAL BOUNDARY CONTINUES TO BE NORTH OF THE FORECAST AREA THIS MORNING. SOME SHOWERS AND THUNDERSTORMS MOVED ACROSS THE SOUTHERN ADIRONDACKS EARLY THIS MORNING...LEAVING UP TO AN INCH OF RAINFALL /ACCORDING TO RADAR ESTIMATES/ IN SPOTS NEAR INDIAN LAKE. THE FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD DURING THE DAY...AS A SUBTROPICAL HIGH OFF THE MID ATLANTIC COAST AT THE SFC...AND ALOFT CONTINUES TO FUNNEL HUMID AIR NORTHWARD. SFC DEWPTS TODAY WILL RISE INTO THE MID AND U60S IN SOME LOCATIONS WITH SOUTH TO SOUTHWEST SFC LAYER WINDS. H850 TEMPS INCREASE TO +16 TO +17C WITH PARTLY TO MOSTLY SUNNY CONDITIONS. MAX TEMPS IN THE M80S TO NEAR 90F WILL BE LIKELY IN THE VALLEYS WITH U70S TO L80S OVER THE MTNS. WEAK MID LEVEL VORTICES MOVING ALONG THE RIM OF THE UPPER LEVEL RIDGE MAY TRIGGER SOME ISOLD-SCT THUNDERSTORMS TODAY. THE BEST 0-6 KM BULK SHEAR IS ACTUALLY JUST NORTH OF THE FCST AREA ACROSS NRN NY AND NRN NEW ENGLAND WITH 20-30 KTS. MOST OF THE ALY FCST AREA WILL BE IN A WEAK SHEAR ENVIRONMENT OF 10-20 KTS FOR PULSE OR VERY LOOSELY ORGANIZED THUNDERSTORMS. FREEZING LEVELS WILL BE HIGH IN THE 12-14 KFT AGL RANGE WITH WBZ HEIGHTS AROUND 11 KFT AGL. SBCAPES WILL BE IN THE 500-1500 J/KG RANGE ACCORDING TO THE GFS. NOT BUYING INTO THE NAM/S FAIRLY WIDESPREAD LOWER 70S DEWPT AIR OVER THE REGION WITH SBCAPES OF 2000-3000 J/KG. THE NEW 12Z NAM...AS WELL AS THE 12Z 3KM HRRR AND THE 12Z LOCAL HIRES WRF SHOW CELLULAR CONVECTION POPPING UP ACROSS THE ADIRONDACKS BY THE EARLY TO MID AFTN...AND MORE ACTIVITY DEVELOPING AND MOVING ACROSS THE MOHAWK VALLEY...CAPITAL REGION AND SRN VT...BY THE MID/LATE AFTN AND INTO THE EVENING HOURS. EACH MODEL HAS THE PLACEMENT/TIMING SLIGHTLY DIFFERENT...BUT THE CONVECTIVE MODE /CELLULAR PULSE TYPE STORMS/ SEEMS TO BE SIMILAR IN EACH MODEL. THIS MORNING/S 12Z KALY SOUNDING SHOWED A PWAT OF 1.62. AS A RESULT...A MENTION OF HVY RAIN HAS BEEN INCLUDED WITH ISOLD-SCT THUNDERSTORMS TODAY IN THE GRIDDED...TEXT FORECASTS...AND HWO STATEMENT. AN ISOLD SEVERE MAY BE POSSIBLE TOO...ESPECIALLY IN THE NRN ZONES...BUT THE FORECASTED WEAK MID LEVEL LAPSE RATES OF LESS THAN 6 C/KM AND LIMITED AMOUNTS OF SHEAR IN THE 0-6 KM LAYER SHOULD PROHIBIT WIDESPREAD STRONG CELLS. SPC MAINTAINS A /SEE TEXT/ AREA ACROSS THE CENTRAL/NORTHERN PART OF THE CWA AND WE WILL CONTINUE TO MONITOR MESOSCALE TRENDS. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... TONIGHT...THE ISOLD TO SCT CONVECTION SHOULD SHRIVEL UP QUICKLY BEFORE MIDNIGHT WITH THE LOSS OF THE DAYTIME HEATING. A PARTIAL CLEARING WILL ALLOW PATCHY FOG JUST ABOUT ANYWHERE IN THE FCST AREA WITH THE MOIST LOW LEVELS. IT HAS BEEN ADDED TO THE FORECAST GRIDS. STICKY CONDITIONS WILL PREVAIL WITH LOWS IN THE MID AND U60S IN THE VALLEYS...AND LOWER TO M60S OVER THE HILLS AND MTNS. MONDAY...THE SULTRY CONDITIONS IN PLACE WILL PROMOTE INCREASED CHANCES OF MORE PULSE THUNDERSTORMS WITH DEEP SHEAR VALUES LESS THAN 15 KTS. SBCAPES WILL SOLIDLY BE IN THE 1000-2000 J/KG RANGE. SOME THUNDERSTORMS MAY BE SLOW MOVERS OR LATCH TO THE TERRAIN FOR A QUICK INCH OR TWO OF RAINFALL IN THE ANOMALOUSLY HIGH PWAT AIR MASS. THE NAM SHOWS HINTS OF A SHORT-WAVE TROUGH IN THE W/SW ALOFT MOVING THROUGH DURING THE AFTERNOON. THE ECMWF/GFS ALSO SHOW A SUBTLE SHORT-WAVE TROUGH IN THE FLOW ALOFT. THE MID LEVEL LAPSE RATES STEEPEN TO AROUND 6.5C/KM ON THE GFS. 850HPA THETA-E VALUES INCREASE TO CLOSE TO 340K ACROSS PORTIONS CNTRL-ERN NY. THE THETA-E RIDGE WEAKENS SLIGHTLY TOWARDS NIGHT FALL WITH THE PASSAGE OF THIS TROUGH. HVY RAIN HAS BEEN INCLUDED WITH THE THUNDERSTORMS AGAIN IN THE GRIDS/TEXT PRODUCTS. H850 TEMPS INCREASE CLOSE TO +17 TO +18C WITH THE GFSMOS TEMPS MUCH WARMER THAN THE METMOS TEMPS. A BLEND WAS USED WITH A SHADING A LITTLE CLOSER TO THE GFSMOS VALUES WITH SOUTHWEST TO WEST WINDS IN THE SFC TO BOUNDARY LAYER...TEMPS MAY SPIKE UP A LITTLE BIT IN THE VALLEYS DUE TO DOWNSLOPING WITH HIGHS IN THE U80S TO L90S WITH U70S TO M80S OVER THE HILLS AND MTNS. APPARENT TEMPS COULD GET INTO M90S OR EVEN A FEW U90S IN THE MID HUDSON VALLEY. MONDAY NIGHT...SOME SUBSIDENCE OR DRYING ALOFT IN THE WAKE OF THE TROUGH WILL ALLOW THE SKIES TO GO AT LEAST PARTLY CLOUDY...ESPECIALLY THE NRN ZONES. PATCHY FOG WILL BE POSSIBLE AGAIN WITH LOWS IN THE 60S. TUE-TUE NIGHT...THE BROKEN RECORD FCST CONTINUES WITH DIURNAL DRIVEN ISOLD-SCT SHOWERS AND THUNDERSTORMS AGAIN. INITIAL CONVECTION WILL LIKELY BE FROM DIFFERENTIAL HEATING BTWN THE MTNS AND VALLEYS...BUT POTENTIAL LAKE BREEZES OR WEAK SFC TROUGHS UPSTREAM WILL HAVE TO BE MONITORED FOR MORE ORGANIZED CONVECTION. STILL FAVORING THE GFS IN TERMS OF SHEAR AND INSTABILITY. SBCAPES WILL LIKELY BE IN THE 1000-1500 J/KG RANGE WITH WEAKER MID LEVEL LAPSE RATES COMPARED TO MONDAY. HIGHS WILL BE SIMILAR TO MON WITH SOME L90S IN THE HUDSON RIVER VALLEY...AND WIDESPREAD 80S OVER THE FCST AREA. MUGGY CONDITIONS WILL CONTINUE OVERNIGHT WITH MID AND U60S IN THE VALLEYS...AND L60S OVER THE HIGH PEAKS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... THE MODEL GUIDANCE AND ENSEMBLES ARE IN GOOD AGREEMENT WITH THE LONGWAVE PATTERN AND CONTINUE TO INDICATE THE SUBTROPICAL RIDGE SETTLES IN OVER THE SOUTHWESTERN UNITED STATES AND AMPLIFIES WITH TROUGHING OVER THE GREAT LAKES REGION AND NORTHEAST INCREASING. OVERALL THIS WILL RESULT IN THE WEATHER BECOMING MORE UNSETTLED OVER THE NORTHEAST AS PIECES OF SHORT WAVE ENERGY MOVE THROUGH THE TROUGH DEEPENING IT. THE DIFFERENCES IN THE GUIDANCE LIES WITH THE TIMING OF INDIVIDUAL SHORT WAVES AND THE MOVEMENT AND PLACEMENT OF BOUNDARIES. A WEAK BACKDOOR FRONT IS EXPECTED TO MOVE SOUTHWARD INTO THE REGION MID WEEK THEN RETURN BACK NORTHWARD AS A WARM FRONT LATE IN THE WEEK AS THE TROUGH DEEPENS OVER THE REGION AND A LOW PRESSURE SYSTEM APPROACHES. THE REGION IS EXPECTED TO BE IN THE WARM SECTOR OF THE SYSTEM INTO THE WEEKEND WITH THE SYSTEM`S COLD FRONT EVENTUALLY CROSSING THE REGION SATURDAY NIGHT/SUNDAY. TEMPERATURES ARE EXPECTED TO RETURN TO MORE SEASONABLE LEVELS. HOWEVER DEWPOINTS WILL REMAIN HIGH...IN THE 60S...MAKING FOR HUMID CONDITIONS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... WITH A VERY WARM AND MUGGY AIR MASS IN PLACE...SCATTERED SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS NORTHERN AND WESTERN PORTIONS OF THE REGION. THERE IS THE POTENTIAL FOR THESE TSRA TO AFFECT KGFL/KALB/KPOU BY THE LATE AFTN OR EVENING HOURS...SO HAVE INCLUDED A TEMPO FOR THOSE SITES. KPOU SHOULD REMAIN FAR ENOUGH TO THE SOUTH AND CAPPED TO AVOID ANY TSTM ACTIVITY. WITHIN ANY TSTM...THERE IS THE POSSIBILITY OF A QUICK BURST OF HVY RAINFALL AND A STRONG WIND GUST AS WELL. ANY TSTM ACTIVITY SHOULD DIMINISH AFTER EVENING WITH THE LOSS OF HEATING. WITH THE HIGH DEWPOINTS AND LIGHT WINDS IN PLACE...SOME FOG WILL DEVELOP TONIGHT...ESP IF ANY TERMINALS RECEIVE ANY RAINFALL. THE SITES MOST LIKELY TO SEE IFR FOG WOULD BE KGFL/KPSF...MAINLY AFTER MIDNIGHT. ANY FOG WILL DISSIPATE SHORTLY AFTER SUNRISE ON MONDAY...ALLOWING FOR VFR CONDITIONS TO RETURN TO ALL SITES FOR MONDAY MORNING. OUTLOOK... MON PM-TUE...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN INTO THE EVNG. MVFR-IFR FOG LATE AT NIGHT INTO EARLY IN THE MORNING. WED...MAINLY VFR. SLIGHT CHC -TSRA/-SHRA. THU-FRI...MAINLY VFR. CHC -TSRA/-SHRA. && .FIRE WEATHER... A WARM AND HUMID AIR MASS WILL CONTINUE TODAY THROUGH THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING THE NEXT FEW DAYS. RH LEVELS WILL REMAIN HIGH EACH NIGHT INTO THE MIDDLE OF NEXT WEEK FOR THE FORMATION OF DEW ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND. NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME. && .HYDROLOGY... FLOWS CONTINUE TO RECEDE TO LATE JUNE SEASONAL LEVELS. THE NEXT 5 DAYS WILL FEATURE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WHICH WILL LIKELY NOT HAVE A SIGNIFICANT IMPACT ON THE MAIN STEM RIVERS. SLOW MOVING THUNDERSTORMS COULD PRODUCE A QUICK INCH OR TWO OF RAINFALL WITH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES OVER THE HYDRO SERVICE AREA. SOME POOR DRAINAGE FLOODING OF LOW LYING AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY INTO THURSDAY. SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH BANKFULL QUICKLY IN THE HEAVY RAINFALL ASSOCIATED WITH THE THUNDERSTORMS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/WASULA NEAR TERM...BGM/FRUGIS/WASULA SHORT TERM...WASULA LONG TERM...IAA AVIATION...FRUGIS FIRE WEATHER...WASULA HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
128 PM EDT SUN JUN 23 2013 .SYNOPSIS... A WARM AND HUMID AIR MASS WILL CONTINUE THIS AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING THE NEXT FEW DAYS. SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE...AND PATCHY FOG WILL BE COMMON WITH MUGGY CONDITIONS EACH NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1026 AM EDT...A DIFFUSE FRONTAL BOUNDARY CONTINUES TO BE NORTH OF THE FORECAST AREA THIS MORNING. SOME SHOWERS AND THUNDERSTORMS MOVED ACROSS THE SOUTHERN ADIRONDACKS EARLY THIS MORNING...LEAVING UP TO AN INCH OF RAINFALL /ACCORDING TO RADAR ESTIMATES/ IN SPOTS NEAR INDIAN LAKE. THE FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD DURING THE DAY...AS A SUBTROPICAL HIGH OFF THE MID ATLANTIC COAST AT THE SFC...AND ALOFT CONTINUES TO FUNNEL HUMID AIR NORTHWARD. SFC DEWPTS TODAY WILL RISE INTO THE MID AND U60S IN SOME LOCATIONS WITH SOUTH TO SOUTHWEST SFC LAYER WINDS. H850 TEMPS INCREASE TO +16 TO +17C WITH PARTLY TO MOSTLY SUNNY CONDITIONS. MAX TEMPS IN THE M80S TO NEAR 90F WILL BE LIKELY IN THE VALLEYS WITH U70S TO L80S OVER THE MTNS. WEAK MID LEVEL VORTICES MOVING ALONG THE RIM OF THE UPPER LEVEL RIDGE MAY TRIGGER SOME ISOLD-SCT THUNDERSTORMS TODAY. THE BEST 0-6 KM BULK SHEAR IS ACTUALLY JUST NORTH OF THE FCST AREA ACROSS NRN NY AND NRN NEW ENGLAND WITH 20-30 KTS. MOST OF THE ALY FCST AREA WILL BE IN A WEAK SHEAR ENVIRONMENT OF 10-20 KTS FOR PULSE OR VERY LOOSELY ORGANIZED THUNDERSTORMS. FREEZING LEVELS WILL BE HIGH IN THE 12-14 KFT AGL RANGE WITH WBZ HEIGHTS AROUND 11 KFT AGL. SBCAPES WILL BE IN THE 500-1500 J/KG RANGE ACCORDING TO THE GFS. NOT BUYING INTO THE NAM/S FAIRLY WIDESPREAD LOWER 70S DEWPT AIR OVER THE REGION WITH SBCAPES OF 2000-3000 J/KG. THE NEW 12Z NAM...AS WELL AS THE 12Z 3KM HRRR AND THE 12Z LOCAL HIRES WRF SHOW CELLULAR CONVECTION POPPING UP ACROSS THE ADIRONDACKS BY THE EARLY TO MID AFTN...AND MORE ACTIVITY DEVELOPING AND MOVING ACROSS THE MOHAWK VALLEY...CAPITAL REGION AND SRN VT...BY THE MID/LATE AFTN AND INTO THE EVENING HOURS. EACH MODEL HAS THE PLACEMENT/TIMING SLIGHTLY DIFFERENT...BUT THE CONVECTIVE MODE /CELLULAR PULSE TYPE STORMS/ SEEMS TO BE SIMILAR IN EACH MODEL. THIS MORNING/S 12Z KALY SOUNDING SHOWED A PWAT OF 1.62. AS A RESULT...A MENTION OF HVY RAIN HAS BEEN INCLUDED WITH ISOLD-SCT THUNDERSTORMS TODAY IN THE GRIDDED...TEXT FORECASTS...AND HWO STATEMENT. AN ISOLD SEVERE MAY BE POSSIBLE TOO...ESPECIALLY IN THE NRN ZONES...BUT THE FORECASTED WEAK MID LEVEL LAPSE RATES OF LESS THAN 6 C/KM AND LIMITED AMOUNTS OF SHEAR IN THE 0-6 KM LAYER SHOULD PROHIBIT WIDESPREAD STRONG CELLS. SPC MAINTAINS A /SEE TEXT/ AREA ACROSS THE CENTRAL/NORTHERN PART OF THE CWA AND WE WILL CONTINUE TO MONITOR MESOSCALE TRENDS. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... TONIGHT...THE ISOLD TO SCT CONVECTION SHOULD SHRIVEL UP QUICKLY BEFORE MIDNIGHT WITH THE LOSS OF THE DAYTIME HEATING. A PARTIAL CLEARING WILL ALLOW PATCHY FOG JUST ABOUT ANYWHERE IN THE FCST AREA WITH THE MOIST LOW LEVELS. IT HAS BEEN ADDED TO THE FORECAST GRIDS. STICKY CONDITIONS WILL PREVAIL WITH LOWS IN THE MID AND U60S IN THE VALLEYS...AND LOWER TO M60S OVER THE HILLS AND MTNS. MONDAY...THE SULTRY CONDITIONS IN PLACE WILL PROMOTE INCREASED CHANCES OF MORE PULSE THUNDERSTORMS WITH DEEP SHEAR VALUES LESS THAN 15 KTS. SBCAPES WILL SOLIDLY BE IN THE 1000-2000 J/KG RANGE. SOME THUNDERSTORMS MAY BE SLOW MOVERS OR LATCH TO THE TERRAIN FOR A QUICK INCH OR TWO OF RAINFALL IN THE ANOMALOUSLY HIGH PWAT AIR MASS. THE NAM SHOWS HINTS OF A SHORT-WAVE TROUGH IN THE W/SW ALOFT MOVING THROUGH DURING THE AFTERNOON. THE ECMWF/GFS ALSO SHOW A SUBTLE SHORT-WAVE TROUGH IN THE FLOW ALOFT. THE MID LEVEL LAPSE RATES STEEPEN TO AROUND 6.5C/KM ON THE GFS. 850HPA THETA-E VALUES INCREASE TO CLOSE TO 340K ACROSS PORTIONS CNTRL-ERN NY. THE THETA-E RIDGE WEAKENS SLIGHTLY TOWARDS NIGHT FALL WITH THE PASSAGE OF THIS TROUGH. HVY RAIN HAS BEEN INCLUDED WITH THE THUNDERSTORMS AGAIN IN THE GRIDS/TEXT PRODUCTS. H850 TEMPS INCREASE CLOSE TO +17 TO +18C WITH THE GFSMOS TEMPS MUCH WARMER THAN THE METMOS TEMPS. A BLEND WAS USED WITH A SHADING A LITTLE CLOSER TO THE GFSMOS VALUES WITH SOUTHWEST TO WEST WINDS IN THE SFC TO BOUNDARY LAYER...TEMPS MAY SPIKE UP A LITTLE BIT IN THE VALLEYS DUE TO DOWNSLOPING WITH HIGHS IN THE U80S TO L90S WITH U70S TO M80S OVER THE HILLS AND MTNS. APPARENT TEMPS COULD GET INTO M90S OR EVEN A FEW U90S IN THE MID HUDSON VALLEY. MONDAY NIGHT...SOME SUBSIDENCE OR DRYING ALOFT IN THE WAKE OF THE TROUGH WILL ALLOW THE SKIES TO GO AT LEAST PARTLY CLOUDY...ESPECIALLY THE NRN ZONES. PATCHY FOG WILL BE POSSIBLE AGAIN WITH LOWS IN THE 60S. TUE-TUE NIGHT...THE BROKEN RECORD FCST CONTINUES WITH DIURNAL DRIVEN ISOLD-SCT SHOWERS AND THUNDERSTORMS AGAIN. INITIAL CONVECTION WILL LIKELY BE FROM DIFFERENTIAL HEATING BTWN THE MTNS AND VALLEYS...BUT POTENTIAL LAKE BREEZES OR WEAK SFC TROUGHS UPSTREAM WILL HAVE TO BE MONITORED FOR MORE ORGANIZED CONVECTION. STILL FAVORING THE GFS IN TERMS OF SHEAR AND INSTABILITY. SBCAPES WILL LIKELY BE IN THE 1000-1500 J/KG RANGE WITH WEAKER MID LEVEL LAPSE RATES COMPARED TO MONDAY. HIGHS WILL BE SIMILAR TO MON WITH SOME L90S IN THE HUDSON RIVER VALLEY...AND WIDESPREAD 80S OVER THE FCST AREA. MUGGY CONDITIONS WILL CONTINUE OVERNIGHT WITH MID AND U60S IN THE VALLEYS...AND L60S OVER THE HIGH PEAKS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... THE MODEL GUIDANCE AND ENSEMBLES ARE IN GOOD AGREEMENT WITH THE LONGWAVE PATTERN AND CONTINUE TO INDICATE THE SUBTROPICAL RIDGE SETTLES IN OVER THE SOUTHWESTERN UNITED STATES AND AMPLIFIES WITH TROUGHING OVER THE GREAT LAKES REGION AND NORTHEAST INCREASING. OVERALL THIS WILL RESULT IN THE WEATHER BECOMING MORE UNSETTLED OVER THE NORTHEAST AS PIECES OF SHORT WAVE ENERGY MOVE THROUGH THE TROUGH DEEPENING IT. THE DIFFERENCES IN THE GUIDANCE LIES WITH THE TIMING OF INDIVIDUAL SHORT WAVES AND THE MOVEMENT AND PLACEMENT OF BOUNDARIES. A WEAK BACKDOOR FRONT IS EXPECTED TO MOVE SOUTHWARD INTO THE REGION MID WEEK THEN RETURN BACK NORTHWARD AS A WARM FRONT LATE IN THE WEEK AS THE TROUGH DEEPENS OVER THE REGION AND A LOW PRESSURE SYSTEM APPROACHES. THE REGION IS EXPECTED TO BE IN THE WARM SECTOR OF THE SYSTEM INTO THE WEEKEND WITH THE SYSTEM`S COLD FRONT EVENTUALLY CROSSING THE REGION SATURDAY NIGHT/SUNDAY. TEMPERATURES ARE EXPECTED TO RETURN TO MORE SEASONABLE LEVELS. HOWEVER DEWPOINTS WILL REMAIN HIGH...IN THE 60S...MAKING FOR HUMID CONDITIONS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... WITH A VERY WARM AND MUGGY AIR MASS IN PLACE...SCATTERED SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS NORTHERN AND WESTERN PORTIONS OF THE REGION. THERE IS THE POTENTIAL FOR THESE TSRA TO AFFECT KGFL/KALB/KPOU BY THE LATE AFTN OR EVENING HOURS...SO HAVE INCLUDED A TEMPO FOR THOSE SITES. KPOU SHOULD REMAIN FAR ENOUGH TO THE SOUTH AND CAPPED TO AVOID ANY TSTM ACTIVITY. WITHIN ANY TSTM...THERE IS THE POSSIBILITY OF A QUICK BURST OF HVY RAINFALL AND A STRONG WIND GUST AS WELL. ANY TSTM ACTIVITY SHOULD DIMINISH AFTER EVENING WITH THE LOSS OF HEATING. WITH THE HIGH DEWPOINTS AND LIGHT WINDS IN PLACE...SOME FOG WILL DEVELOP TONIGHT...ESP IF ANY TERMINALS RECEIVE ANY RAINFALL. THE SITES MOST LIKELY TO SEE IFR FOG WOULD BE KGFL/KPSF...MAINLY AFTER MIDNIGHT. ANY FOG WILL DISSIPATE SHORTLY AFTER SUNRISE ON MONDAY...ALLOWING FOR VFR CONDITIONS TO RETURN TO ALL SITES FOR MONDAY MORNING. OUTLOOK... MON PM-TUE...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN INTO THE EVNG. MVFR-IFR FOG LATE AT NIGHT INTO EARLY IN THE MORNING. WED...MAINLY VFR. SLIGHT CHC -TSRA/-SHRA. THU-FRI...MAINLY VFR. CHC -TSRA/-SHRA. && .FIRE WEATHER... A WARM AND HUMID AIR MASS WILL CONTINUE TODAY THROUGH THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING THE NEXT FEW DAYS. RH LEVELS WILL REMAIN HIGH EACH NIGHT INTO THE MIDDLE OF NEXT WEEK FOR THE FORMATION OF DEW ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND. NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME. && .HYDROLOGY... FLOWS CONTINUE TO RECEDE TO LATE JUNE SEASONAL LEVELS. THE NEXT 5 DAYS WILL FEATURE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WHICH WILL LIKELY NOT HAVE A SIGNIFICANT IMPACT ON THE MAIN STEM RIVERS. SLOW MOVING THUNDERSTORMS COULD PRODUCE A QUICK INCH OR TWO OF RAINFALL WITH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES OVER THE HYDRO SERVICE AREA. SOME POOR DRAINAGE FLOODING OF LOW LYING AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY INTO THURSDAY. SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH BANKFULL QUICKLY IN THE HEAVY RAINFALL ASSOCIATED WITH THE THUNDERSTORMS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/WASULA NEAR TERM...FRUGIS/WASULA SHORT TERM...WASULA LONG TERM...IAA AVIATION...FRUGIS FIRE WEATHER...WASULA HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1026 AM EDT SUN JUN 23 2013 .SYNOPSIS... A WARM AND HUMID AIR MASS WILL CONTINUE THIS AFTERNOON THROUGH THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING THE NEXT FEW DAYS. SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE...AND PATCHY FOG WILL BE COMMON WITH MUGGY CONDITIONS EACH NIGHT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1026 AM EDT...A DIFFUSE FRONTAL BOUNDARY CONTINUES TO BE NORTH OF THE FORECAST AREA THIS MORNING. SOME SHOWERS AND THUNDERSTORMS MOVED ACROSS THE SOUTHERN ADIRONDACKS EARLY THIS MORNING...LEAVING UP TO AN INCH OF RAINFALL /ACCORDING TO RADAR ESTIMATES/ IN SPOTS NEAR INDIAN LAKE. THE FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD DURING THE DAY...AS A SUBTROPICAL HIGH OFF THE MID ATLANTIC COAST AT THE SFC...AND ALOFT CONTINUES TO FUNNEL HUMID AIR NORTHWARD. SFC DEWPTS TODAY WILL RISE INTO THE MID AND U60S IN SOME LOCATIONS WITH SOUTH TO SOUTHWEST SFC LAYER WINDS. H850 TEMPS INCREASE TO +16 TO +17C WITH PARTLY TO MOSTLY SUNNY CONDITIONS. MAX TEMPS IN THE M80S TO NEAR 90F WILL BE LIKELY IN THE VALLEYS WITH U70S TO L80S OVER THE MTNS. WEAK MID LEVEL VORTICES MOVING ALONG THE RIM OF THE UPPER LEVEL RIDGE MAY TRIGGER SOME ISOLD-SCT THUNDERSTORMS TODAY. THE BEST 0-6 KM BULK SHEAR IS ACTUALLY JUST NORTH OF THE FCST AREA ACROSS NRN NY AND NRN NEW ENGLAND WITH 20-30 KTS. MOST OF THE ALY FCST AREA WILL BE IN A WEAK SHEAR ENVIRONMENT OF 10-20 KTS FOR PULSE OR VERY LOOSELY ORGANIZED THUNDERSTORMS. FREEZING LEVELS WILL BE HIGH IN THE 12-14 KFT AGL RANGE WITH WBZ HEIGHTS AROUND 11 KFT AGL. SBCAPES WILL BE IN THE 500-1500 J/KG RANGE ACCORDING TO THE GFS. NOT BUYING INTO THE NAM/S FAIRLY WIDESPREAD LOWER 70S DEWPT AIR OVER THE REGION WITH SBCAPES OF 2000-3000 J/KG. THE NEW 12Z NAM...AS WELL AS THE 12Z 3KM HRRR AND THE 12Z LOCAL HIRES WRF SHOW CELLULAR CONVECTION POPPING UP ACROSS THE ADIRONDACKS BY THE EARLY TO MID AFTN...AND MORE ACTIVITY DEVELOPING AND MOVING ACROSS THE MOHAWK VALLEY...CAPITAL REGION AND SRN VT...BY THE MID/LATE AFTN AND INTO THE EVENING HOURS. EACH MODEL HAS THE PLACEMENT/TIMING SLIGHTLY DIFFERENT...BUT THE CONVECTIVE MODE /CELLULAR PULSE TYPE STORMS/ SEEMS TO BE SIMILAR IN EACH MODEL. THIS MORNING/S 12Z KALY SOUNDING SHOWED A PWAT OF 1.62. AS A RESULT...A MENTION OF HVY RAIN HAS BEEN INCLUDED WITH ISOLD-SCT THUNDERSTORMS TODAY IN THE GRIDDED...TEXT FORECASTS...AND HWO STATEMENT. AN ISOLD SEVERE MAY BE POSSIBLE TOO...ESPECIALLY IN THE NRN ZONES...BUT THE FORECASTED WEAK MID LEVEL LAPSE RATES OF LESS THAN 6 C/KM AND LIMITED AMOUNTS OF SHEAR IN THE 0-6 KM LAYER SHOULD PROHIBIT WIDESPREAD STRONG CELLS. SPC MAINTAINS A /SEE TEXT/ AREA ACROSS THE CENTRAL/NORTHERN PART OF THE CWA AND WE WILL CONTINUE TO MONITOR MESOSCALE TRENDS. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... TONIGHT...THE ISOLD TO SCT CONVECTION SHOULD SHRIVEL UP QUICKLY BEFORE MIDNIGHT WITH THE LOSS OF THE DAYTIME HEATING. A PARTIAL CLEARING WILL ALLOW PATCHY FOG JUST ABOUT ANYWHERE IN THE FCST AREA WITH THE MOIST LOW LEVELS. IT HAS BEEN ADDED TO THE FORECAST GRIDS. STICKY CONDITIONS WILL PREVAIL WITH LOWS IN THE MID AND U60S IN THE VALLEYS...AND LOWER TO M60S OVER THE HILLS AND MTNS. MONDAY...THE SULTRY CONDITIONS IN PLACE WILL PROMOTE INCREASED CHANCES OF MORE PULSE THUNDERSTORMS WITH DEEP SHEAR VALUES LESS THAN 15 KTS. SBCAPES WILL SOLIDLY BE IN THE 1000-2000 J/KG RANGE. SOME THUNDERSTORMS MAY BE SLOW MOVERS OR LATCH TO THE TERRAIN FOR A QUICK INCH OR TWO OF RAINFALL IN THE ANOMALOUSLY HIGH PWAT AIR MASS. THE NAM SHOWS HINTS OF A SHORT-WAVE TROUGH IN THE W/SW ALOFT MOVING THROUGH DURING THE AFTERNOON. THE ECMWF/GFS ALSO SHOW A SUBTLE SHORT-WAVE TROUGH IN THE FLOW ALOFT. THE MID LEVEL LAPSE RATES STEEPEN TO AROUND 6.5C/KM ON THE GFS. 850HPA THETA-E VALUES INCREASE TO CLOSE TO 340K ACROSS PORTIONS CNTRL-ERN NY. THE THETA-E RIDGE WEAKENS SLIGHTLY TOWARDS NIGHT FALL WITH THE PASSAGE OF THIS TROUGH. HVY RAIN HAS BEEN INCLUDED WITH THE THUNDERSTORMS AGAIN IN THE GRIDS/TEXT PRODUCTS. H850 TEMPS INCREASE CLOSE TO +17 TO +18C WITH THE GFSMOS TEMPS MUCH WARMER THAN THE METMOS TEMPS. A BLEND WAS USED WITH A SHADING A LITTLE CLOSER TO THE GFSMOS VALUES WITH SOUTHWEST TO WEST WINDS IN THE SFC TO BOUNDARY LAYER...TEMPS MAY SPIKE UP A LITTLE BIT IN THE VALLEYS DUE TO DOWNSLOPING WITH HIGHS IN THE U80S TO L90S WITH U70S TO M80S OVER THE HILLS AND MTNS. APPARENT TEMPS COULD GET INTO M90S OR EVEN A FEW U90S IN THE MID HUDSON VALLEY. MONDAY NIGHT...SOME SUBSIDENCE OR DRYING ALOFT IN THE WAKE OF THE TROUGH WILL ALLOW THE SKIES TO GO AT LEAST PARTLY CLOUDY...ESPECIALLY THE NRN ZONES. PATCHY FOG WILL BE POSSIBLE AGAIN WITH LOWS IN THE 60S. TUE-TUE NIGHT...THE BROKEN RECORD FCST CONTINUES WITH DIURNAL DRIVEN ISOLD-SCT SHOWERS AND THUNDERSTORMS AGAIN. INITIAL CONVECTION WILL LIKELY BE FROM DIFFERENTIAL HEATING BTWN THE MTNS AND VALLEYS...BUT POTENTIAL LAKE BREEZES OR WEAK SFC TROUGHS UPSTREAM WILL HAVE TO BE MONITORED FOR MORE ORGANIZED CONVECTION. STILL FAVORING THE GFS IN TERMS OF SHEAR AND INSTABILITY. SBCAPES WILL LIKELY BE IN THE 1000-1500 J/KG RANGE WITH WEAKER MID LEVEL LAPSE RATES COMPARED TO MONDAY. HIGHS WILL BE SIMILAR TO MON WITH SOME L90S IN THE HUDSON RIVER VALLEY...AND WIDESPREAD 80S OVER THE FCST AREA. MUGGY CONDITIONS WILL CONTINUE OVERNIGHT WITH MID AND U60S IN THE VALLEYS...AND L60S OVER THE HIGH PEAKS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... THE MODEL GUIDANCE AND ENSEMBLES ARE IN GOOD AGREEMENT WITH THE LONGWAVE PATTERN AND CONTINUE TO INDICATE THE SUBTROPICAL RIDGE SETTLES IN OVER THE SOUTHWESTERN UNITED STATES AND AMPLIFIES WITH TROUGHING OVER THE GREAT LAKES REGION AND NORTHEAST INCREASING. OVERALL THIS WILL RESULT IN THE WEATHER BECOMING MORE UNSETTLED OVER THE NORTHEAST AS PIECES OF SHORT WAVE ENERGY MOVE THROUGH THE TROUGH DEEPENING IT. THE DIFFERENCES IN THE GUIDANCE LIES WITH THE TIMING OF INDIVIDUAL SHORT WAVES AND THE MOVEMENT AND PLACEMENT OF BOUNDARIES. A WEAK BACKDOOR FRONT IS EXPECTED TO MOVE SOUTHWARD INTO THE REGION MID WEEK THEN RETURN BACK NORTHWARD AS A WARM FRONT LATE IN THE WEEK AS THE TROUGH DEEPENS OVER THE REGION AND A LOW PRESSURE SYSTEM APPROACHES. THE REGION IS EXPECTED TO BE IN THE WARM SECTOR OF THE SYSTEM INTO THE WEEKEND WITH THE SYSTEM`S COLD FRONT EVENTUALLY CROSSING THE REGION SATURDAY NIGHT/SUNDAY. TEMPERATURES ARE EXPECTED TO RETURN TO MORE SEASONABLE LEVELS. HOWEVER DEWPOINTS WILL REMAIN HIGH...IN THE 60S...MAKING FOR HUMID CONDITIONS. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... SCATTERED STORMS CONTINUE TO MOVE ACROSS NORTHERN NEW YORK STATE IN THE VICINITY OF A WEAK SURFACE BOUNDARY. CHANCES FOR CONVECTION WILL INCREASE AND SPREAD SOUTHWARD ACROSS MUCH OF THE FORECAST AREA AS ANOTHER WEAK UPPER LEVEL DISTURBANCE APPROACHES AND MOVING ACROSS THE REGION. EXPECTING ISOLATED TO SCATTERED CONVECTION ESPECIALLY THIS AFTERNOON INTO EARLY EVENING HOURS. HAVE ADDRESSED THIS THREAT WITH VCSH IN TAFS EXCEPT NOT KPOU AS ACTIVITY SHOULD BE TO THEIR NORTH. DEWPOINT TEMPERATURES WILL BE ON THE RISE TODAY WELL INTO THE 60S SO EXPECT SOME FOG TO DEVELOP TONIGHT...MAINLY MVFR AS WILL HAVE CLOUDS ACROSS THE REGION. SOUTH TO SOUTHWEST WINDS TODAY AT 8 TO 12 KNOTS WITH SOME GUSTS INTO THE TEENS AT KALB AND KPSF. WINDS WILL WEAKEN DURING THE EVENING BECOMING LIGHT AND VARIABLE FOR THE OVERNIGHT. OUTLOOK... MON-TUE...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN INTO THE EVNG. MVFR-IFR FOG LATE AT NIGHT INTO EARLY IN THE MORNING. WED...MAINLY VFR. SLIGHT CHC -TSRA/-SHRA. THU...MAINLY VFR. CHC -TSRA/-SHRA. && .FIRE WEATHER... A WARM AND HUMID AIR MASS WILL CONTINUE TODAY THROUGH THE MIDDLE OF NEXT WEEK. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING THE NEXT FEW DAYS. RH LEVELS WILL REMAIN HIGH EACH NIGHT INTO THE MIDDLE OF NEXT WEEK FOR THE FORMATION OF DEW ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND. NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME. && .HYDROLOGY... FLOWS CONTINUE TO RECEDE TO LATE JUNE SEASONAL LEVELS. THE NEXT 5 DAYS WILL FEATURE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WHICH WILL LIKELY NOT HAVE A SIGNIFICANT IMPACT ON THE MAIN STEM RIVERS. SLOW MOVING THUNDERSTORMS COULD PRODUCE A QUICK INCH OR TWO OF RAINFALL WITH HIGHER THAN NORMAL PRECIPITABLE WATER VALUES OVER THE HYDRO SERVICE AREA. SOME POOR DRAINAGE FLOODING OF LOW LYING AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY INTO THURSDAY. SOME SMALL STREAMS...CREEKS...AND BROOKS MAY REACH BANKFULL QUICKLY IN THE HEAVY RAINFALL ASSOCIATED WITH THE THUNDERSTORMS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/WASULA NEAR TERM...FRUGIS/WASULA SHORT TERM...WASULA LONG TERM...IAA AVIATION...IAA FIRE WEATHER...WASULA HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1107 PM EDT MON JUN 24 2013 .UPDATE... HAVE MADE SEVERAL TWEAKS TO GRIDS THROUGH THE EVENING...MAINLY TO UPDATE TRENDS IN POPS. REDUCED POPS SIGNIFICANTLY ESPECIALLY NORTH AND TRENDED THEM DOWN SOUTH AS WELL...WITH AN OVERALL REDUCTION THROUGH THE OVERNIGHT HOURS...TRENDING BACK UP DURING THE DAY ON TUESDAY. ADDED PATCHY FOG TO WEATHER GRID WORDING. UPDATED PRODUCTS ALREADY SENT. TDP && .PREV DISCUSSION... /ISSUED 738 PM EDT MON JUN 24 2013/ PREV DISCUSSION... /ISSUED 339 PM EDT MON JUN 24 2013/ SHORT TERM /TONIGHT THROUGH TUESDAY/... 500MB SURFACE ANALYSIS SHOWS A TROUGH SITUATED ACROSS NORTHERN GA...CENTRAL AL AND SOUTHEAST MS. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN THE BASE OF THE TROUGH THIS AFTERNOON...AND CONTINUE TO APPROACH WESTERN GA. THE LATEST RUN OF THE HRRR HAS THE ACTIVITY FROM THE WEST CONGEALING WITH THE SE ACTIVITY LATE THIS AFTERNOON. ACTIVITY SHOULD DECREASE IN STRENGTH AND COVERAGE WITH THE LOSS OF HEATING FOR THE EARLY EVENING HOURS. FOR OVERNIGHT...WV LOOP SHOWS A GOOD PIECE OF SHORTWAVE ENERGY DROPPING SE IN THE FLOW ACROSS W KY THIS AFTERNOON. MODELS DO DEVELOP SCT ACTIVITY MAINLY ACROSS NORTHERN GA OVERNIGHT. WITH SOME MARGINAL INSTABILITY PRESENT OVERNIGHT...SCT SHRA/TSRA SEEM VERY REASONABLE. THE 500MB TROUGH AXIS IS PROGGED TO BE ACROSS THE CENTRAL CWFA DURING THE DAY TOMORROW. THIS SHOULD LEAD TO A LITTLE MORE COVERAGE OF STORMS ACROSS THE REGION. PWATS REMAIN THE SAME ACROSS NORTHERN GA...BUT WILL CREEP UP TO AROUND 2 INCHES ACROSS THE CENTRAL AND SOUTHERN CWFA. IN ADDITION...BL WINDS REMAIN VERY LIGHT (AOB 15K)...SO MOVEMENT OF STORMS WILL BE VERY SLOW OR NEARLY STATIONARY. EVEN THOUGH THE ATMOS WILL BE MARGINALLY UNSTABLE AT THE SURFACE...MID LEVEL LAPSE RATES AND SHEAR REMAIN VERY WEAK. THE POTENTIAL FOR SEVERE WEATHER REMAINS LOW...BUT STRONG THUNDERSTORMS ARE POSSIBLE...WITH AN ISOLATED SEVERE STORM NOT OUT OF THE QUESTION. NLISTEMAA LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... DIURNAL CONVECTION EXPECTED TO CONTINUE ACROSS THE AREA EACH AFTERNOON AND EVENING THROUGH DAY 7. MODELS IN GOOD AGREEMENT WITH SURFACE RIDGE LOSING ITS GRIP ON THE SOUTHEAST BY WEEKS END. THEY ARE ALSO IN GOOD AGREEMENT WITH THE UPPER LEVEL RIDGE BUILDING AND REMAINING OVER THE WESTERN US AS LONG WAVE TROUGH SETS UP OVER THE EAST COAST BY FRIDAY. WITH THE EASTERN EXTENT OF THE UPPER LEVEL RIDGE MORE LIMITED THAN PREVIOUSLY EXPECTED...HAVE COOLED EXTENDED HIGH TEMPERATURES A DEGREE OR TWO. STILL LOOKING FOR HIGHS IN THE UPPER 80S AND LOW 90S. HAVE INCREASED POPS SOMEWHAT FOR THE WEEKEND...AND EXPECT THIS UPWARD TREND IN THE FORECAST TO CONTINUE IN THE COMING DAYS. ENHANCED MOISTURE ACROSS THE REGION AS A RESULT OF THE UPPER LEVEL TROUGH AND ASSOCIATED FRONTAL BOUNDARY SHOULD SUPPORT MORE SIGNIFICANT COVERAGE OF PRECIP ACTIVITY. ANTICIPATE FRONTAL PASSAGE BY EARLY NEXT WEEK...WITH DROP IN POPS AND SLIGHTLY COOLER TEMPERATURES IN STORE AS A RESULT. 31/01 AVIATION... 00Z UPDATE... MOST CONVECTION HAS MOVED OUT OF THE AREA THIS EVENING...BUT HAVE KEPT VCSH LINGERING FOR A FEW HOURS. SHOULD SEE PATCHY MVFR FOG DEVELOPING OVERNIGHT...CANNOT RULE OUT INTERMITTENT IFR OR LOWER FOG DEPENDING ON WHERE HEAVIEST RAIN WAS LOCATED THIS AFTERNOON. GUIDANCE POINTING TO A BRIEF PERIOD OF MVFR CIGS AROUND 12Z TUESDAY...FOR NOW HAVE ONLY INTRODUCED SCT015 EXCEPT AT MCN WHERE BROUGHT IN BKN015. EXPECT LIFTING BY LATE MORNING BUT CIGS REMAINING BKN LOW VFR. WINDS GENERALLY SW TO SSW THROUGH THE PERIOD...THOUGH MAY SEE BRIEF SSE OVERNIGHT. EXPECT SCT CONVECTION AGAIN TUESDAY AFTERNOON. //ATL CONFIDENCE...00Z UPDATE... MEDIUM-LOW ON CIGS OVERNIGHT. HIGH ON OCCURRENCE OF CONVECTION TUESDAY...MEDIUM ON IMPACTS TO ATL. MEDIUM-HIGH ON WINDS. TDP && .PRELIMINARY POINT TEMPS/POPS... ATHENS 69 87 69 90 / 30 50 30 30 ATLANTA 70 86 71 88 / 30 50 30 30 BLAIRSVILLE 64 81 64 86 / 40 50 20 40 CARTERSVILLE 69 88 69 89 / 20 50 20 30 COLUMBUS 71 91 72 92 / 50 40 30 30 GAINESVILLE 68 85 70 87 / 20 50 30 30 MACON 71 89 71 90 / 60 50 30 30 ROME 68 89 69 91 / 20 40 10 30 PEACHTREE CITY 69 87 69 88 / 30 50 30 30 VIDALIA 72 88 73 92 / 50 50 30 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
738 PM EDT MON JUN 24 2013 .PREV DISCUSSION... /ISSUED 339 PM EDT MON JUN 24 2013/ SHORT TERM /TONIGHT THROUGH TUESDAY/... 500MB SURFACE ANALYSIS SHOWS A TROUGH SITUATED ACROSS NORTHERN GA...CENTRAL AL AND SOUTHEAST MS. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN THE BASE OF THE TROUGH THIS AFTERNOON...AND CONTINUE TO APPROACH WESTERN GA. THE LATEST RUN OF THE HRRR HAS THE ACTIVITY FROM THE WEST CONGEALING WITH THE SE ACTIVITY LATE THIS AFTERNOON. ACTIVITY SHOULD DECREASE IN STRENGTH AND COVERAGE WITH THE LOSS OF HEATING FOR THE EARLY EVENING HOURS. FOR OVERNIGHT...WV LOOP SHOWS A GOOD PIECE OF SHORTWAVE ENERGY DROPPING SE IN THE FLOW ACROSS W KY THIS AFTERNOON. MODELS DO DEVELOP SCT ACTIVITY MAINLY ACROSS NORTHERN GA OVERNIGHT. WITH SOME MARGINAL INSTABILITY PRESENT OVERNIGHT...SCT SHRA/TSRA SEEM VERY REASONABLE. THE 500MB TROUGH AXIS IS PROGGED TO BE ACROSS THE CENTRAL CWFA DURING THE DAY TOMORROW. THIS SHOULD LEAD TO A LITTLE MORE COVERAGE OF STORMS ACROSS THE REGION. PWATS REMAIN THE SAME ACROSS NORTHERN GA...BUT WILL CREEP UP TO AROUND 2 INCHES ACROSS THE CENTRAL AND SOUTHERN CWFA. IN ADDITION...BL WINDS REMAIN VERY LIGHT (AOB 15K)...SO MOVEMENT OF STORMS WILL BE VERY SLOW OR NEARLY STATIONARY. EVEN THOUGH THE ATMOS WILL BE MARGINALLY UNSTABLE AT THE SURFACE...MID LEVEL LAPSE RATES AND SHEAR REMAIN VERY WEAK. THE POTENTIAL FOR SEVERE WEATHER REMAINS LOW...BUT STRONG THUNDERSTORMS ARE POSSIBLE...WITH AN ISOLATED SEVERE STORM NOT OUT OF THE QUESTION. NLISTEMAA LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... DIURNAL CONVECTION EXPECTED TO CONTINUE ACROSS THE AREA EACH AFTERNOON AND EVENING THROUGH DAY 7. MODELS IN GOOD AGREEMENT WITH SURFACE RIDGE LOSING ITS GRIP ON THE SOUTHEAST BY WEEKS END. THEY ARE ALSO IN GOOD AGREEMENT WITH THE UPPER LEVEL RIDGE BUILDING AND REMAINING OVER THE WESTERN US AS LONG WAVE TROUGH SETS UP OVER THE EAST COAST BY FRIDAY. WITH THE EASTERN EXTENT OF THE UPPER LEVEL RIDGE MORE LIMITED THAN PREVIOUSLY EXPECTED...HAVE COOLED EXTENDED HIGH TEMPERATURES A DEGREE OR TWO. STILL LOOKING FOR HIGHS IN THE UPPER 80S AND LOW 90S. HAVE INCREASED POPS SOMEWHAT FOR THE WEEKEND...AND EXPECT THIS UPWARD TREND IN THE FORECAST TO CONTINUE IN THE COMING DAYS. ENHANCED MOISTURE ACROSS THE REGION AS A RESULT OF THE UPPER LEVEL TROUGH AND ASSOCIATED FRONTAL BOUNDARY SHOULD SUPPORT MORE SIGNIFICANT COVERAGE OF PRECIP ACTIVITY. ANTICIPATE FRONTAL PASSAGE BY EARLY NEXT WEEK...WITH DROP IN POPS AND SLIGHTLY COOLER TEMPERATURES IN STORE AS A RESULT. 31/01 && .AVIATION... 00Z UPDATE... MOST CONVECTION HAS MOVED OUT OF THE AREA THIS EVENING...BUT HAVE KEPT VCSH LINGERING FOR A FEW HOURS. SHOULD SEE PATCHY MVFR FOG DEVELOPING OVERNIGHT...CANNOT RULE OUT INTERMITTENT IFR OR LOWER FOG DEPENDING ON WHERE HEAVIEST RAIN WAS LOCATED THIS AFTERNOON. GUIDANCE POINTING TO A BRIEF PERIOD OF MVFR CIGS AROUND 12Z TUESDAY...FOR NOW HAVE ONLY INTRODUCED SCT015 EXCEPT AT MCN WHERE BROUGHT IN BKN015. EXPECT LIFTING BY LATE MORNING BUT CIGS REMAINING BKN LOW VFR. WINDS GENERALLY SW TO SSW THROUGH THE PERIOD...THOUGH MAY SEE BRIEF SSE OVERNIGHT. EXPECT SCT CONVECTION AGAIN TUESDAY AFTERNOON. //ATL CONFIDENCE...00Z UPDATE... MEDIUM-LOW ON CIGS OVERNIGHT. HIGH ON OCCURRENCE OF CONVECTION TUESDAY...MEDIUM ON IMPACTS TO ATL. MEDIUM-HIGH ON WINDS. TDP && .PRELIMINARY POINT TEMPS/POPS... ATHENS 69 87 69 90 / 30 50 30 30 ATLANTA 70 86 71 88 / 30 50 30 30 BLAIRSVILLE 64 81 64 86 / 40 50 20 40 CARTERSVILLE 69 88 69 89 / 20 50 20 30 COLUMBUS 71 91 72 92 / 50 40 30 30 GAINESVILLE 68 85 70 87 / 20 50 30 30 MACON 71 89 71 90 / 60 50 30 30 ROME 68 89 69 91 / 20 40 10 30 PEACHTREE CITY 69 87 69 88 / 30 50 30 30 VIDALIA 72 88 73 92 / 50 50 30 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
904 PM CDT MON JUN 24 2013 .DISCUSSION... ISSUED 855 PM CDT MON JUN 24 2013 ANOTHER MCS EXITING THE CWA THIS EVENING...LEAVING A COOLER AND MORE HUMID BOUNDARY LAYER IN ITS WAKE. WILL BE ADJUSTING THE HOURLY TEMPS AND OVERNIGHT LOWS AS WELL AS SOME OF THE AREA WILL BE SEEING THEIR LOWS NOW...IN THE REMAINING COLD AIR FROM CONVECTION. SOUTHERLY WINDS WILL BRING IN WARMER TEMPS FROM THE SOUTH TO COUNTER ANY ADDITIONAL RADIATIONAL COOLING AFTER SUNSET. WILL WATCH CLOSELY FOR DEVELOPMENT OF FOG...BUT SHOULD REMAIN PATCHY IF IT DEVELOPS. ADDITIONAL SHOWER ACTIVITY REMAINING TO THE NORTH IN HRRR AND THE RUC...BUT WITH SO MANY BOUNDARIES OUT THERE FROM DYING CONVECTION...WILL MAINTAIN A LOW POP OVERNIGHT AFTER 06Z. HJS && .AVIATION... ISSUED 658 PM CDT MON JUN 24 2013 MOSTLY GENERIC FORECAST YET AGAIN WITH THE POOR MODEL HANDLING OF THE MCS TRAIN OVER THE REGION. ADJUSTING FORECAST IN THE SHORT TERM TO HANDLE THE SLOWLY DWINDLING CONVECTION. PRECIP HOLDING TOGETHER FOR CMI AND BMI...BUT HAVE PULLED MOST PRECIP FOR THE NEXT FEW HOURS. CONCERN FOR PRECIP CONTINUES THROUGH TOMORROW THOUGH MODELS ARE ALL OVER THE PLACE. MOST FAITH IN HRRR FOR NOW...WHICH HAS A MORE SCT SIGNATURE. KEEPING MENTION OF VCTS THROUGH TOMORROW WITH SCT CU AND BKN MID CLOUDS. VFR THROUGHOUT FOR NOW WITH EXCEPTION OF UNDER CONVECTION. ANY RAPID CLEARING IN THE SHORT TERM HOWEVER WILL UP THE RISK OF A VISBY DROP. HJS && .PREV DISCUSSION... ISSUED 300 PM CDT MON JUN 24 2013 THE SHORT TERM THROUGH WEDNESDAY WILL BE DOMINATED BY PERIODIC BOUTS OF SEVERE STORMS AND FLASH FLOODING...ALONG WITH HIGH HEAT AND HUMIDITY. A COLD FRONT SHOULD PUSH ACROSS ILLINOIS LATE IN THE WEEK PROVIDING SOME RELIEF FROM THE HEAT AND HUMIDITY AND DAILY THUNDERSTORMS. MUCH MORE COMFORTABLE CONDITIONS SHOULD DEVELOP NEXT WEEKEND. BASED ON THE 3-5" OF RAIN FROM PEORIA AND NORTH...WE DECIDED TO INCLUDE OUR NORTHERN 5 COUNTIES IN A FLASH FLOOD WATCH THROUGH TONIGHT DUE TO THE HEAVY RAIN POTENTIAL AGAIN. SHORT TERM...TONIGHT THROUGH WEDNESDAY. INITIAL SEVERE STORM WATCH IS IN EFFECT UNTIL 7 PM FOR OUR WESTERN COUNTIES BUT ANOTHER WATCH FOR AREAS NORTHEAST OF THAT WATCH MAY BE COMING SOON. BASED ON RADAR ANALYSIS...THE SOUTHERN END OF THE LINE OF STORMS IN N MO AND E IOWA APPEARS TO BE ERODING EARLY ON. WE COULD SEE ADDITIONAL DEVELOPMENT ON THE SOUTHERN FLANK AIDED BY INCREASING MID-LEVEL FLOW AND MOISTURE CONVERGENCE. IF NOT...THE SOUTHERN COUNTIES IN THE WATCH WILL NOT BE AFFECTED AS MUCH WITH THIS ROUND OF STORMS. CORFIDI VECTORS ARE SHOWING THE LINE SHOULD MAINTAIN ITS MOTION TO THE EAST-NORTHEAST AS IT MOVES ACROSS IL...WHICH WILL MAKE IT MU-CAPE VALUES ARE CLIMBING TO NEAR 3000 J/KG AS SUNSHINE AHEAD OF THE LINE HAS HELPED BOOST SURFACE TEMPERATURES INTO THE UPPER 80S WITH SURFACE DEWPOINTS IN THE LOWER 70S. SURFACE BASED CONVECTION WILL AID IN DOWNBURST WINDS BEING ABLE TO REACH THE GROUND. SPC MESO-ANALYSIS SHOWS DOWNBURST CAPE VALUES AROUND 1100 J/KG...WHICH ALSO POINTS TOWARD EFFICIENT MOMENTUM TRANSFER TO THE SURFACE AND DAMAGING WINDS. WITH VGP ABOVE 0.2 ACROSS OUR NORTHERN COUNTIES...WE COULD SEE SOME ROTATING EMBEDDED SUPERCELLS WITH A TORNADO POSSIBLE. THE LINE OF STORMS SHOULD REACH OUR WESTERN COUNTIES AROUND 4 PM...AND PROGRESS EASTWARD TO NEAR BMI BY 6 PM AND INTO INDIANA BY 8-9 PM. STRATIFORM RAIN BEHIND THE LINE MAY LINGER FOR A FEW HOURS. SATELLITE IMAGES SHOW A WEAK SHORTWAVE IN THE WAKE OF THIS COMPLEX...SO A FEW ADDITIONAL THUNDERSTORMS MAY AFFECT OUR NW COUNTIES THROUGH MORNING. THEREFORE WE KEPT CHANCE POPS IN THE NW AFTER MIDNIGHT. ANOTHER ROUND OF SEVERE STORMS WILL BE POSSIBLE ON TUESDAY...MAINLY NORTH OF I-72/74-DANVILLE. WE ORIGINALLY HAD EXPECTED SOME UPPER LEVEL RIDGING TO PROVIDE A BREAK IN THE STORMS...AND WE STILL MAY SEE DRY CONDITIONS FOR MUCH OF THE DAY. HOWEVER...SPC HAS EXPANDED THE DAY 2 SLIGHT RISK FARTHER SOUTH TO INCLUDE A LARGE PORTION OF OUR FORECAST AREA...SO WE DECIDED TO ACKNOWLEDGE THE SEVERE POTENTIAL WITH SLIGHTLY HIGHER POPS. WE WILL HAVE A BETTER CHANCE OF BEING CAPPED TUES AS THE MID LEVELS WARM. HOWEVER...ISOLATED AREAS THAT DO BREAK THE CAP WILL HAVE A GREAT DEAL OF ML-CAPE FOR VIGOROUS UPDRAFTS. WE STILL MAINLY HAVE SLIGHT CHANCE POPS EXCEPT FOR NORTH OF I-74 WHERE WE WENT WITH CHANCE POPS. WEDNESDAY SHOULD SEE INCREASING BETTER DESTABILIZATION OF THE LOWER TROP AS THE UPPER RIDGE BEGINS TO BREAK DOWN IN RESPONSE TO A PROGRESSIVE TROUGH FROM CANADA. SURFACE HEAT AND HUMIDITY WILL REMAIN HIGH...BUT SUNSHINE MAY BE A BIT MORE LIMITED IF CONVECTION DEVELOPS EARLIER IN THE AFTERNOON. TUES AND WED WILL HAVE POTENTIAL FOR HEAT INDEX READINGS AROUND 100 IN MANY AREAS BASED ON THE AMOUNT OF SUNSHINE AND WHERE THE CIRRUS SHIELD DEVELOPS AHEAD OF CONVECTION. STILL...VERY UNCOMFORTABLE CONDITIONS. LONG TERM...THURSDAY THROUGH MONDAY. THE MODELS ALL SHOW A COLD FRONTAL PASSAGE AT SOME POINT BEGINNING LATE WED NIGHT OR THURSDAY...BUT THE ARRIVAL OF COLDER AIR DELAYED UNTIL FRIDAY INTO FRIDAY NIGHT AS A SECONDARY PUSH OF CANADIAN AIR OCCURS. WE MAY SEE A FEW SHOWERS OR STORMS IN THE EAST THURSDAY AS THE COLD FRONT DEPARTS...WITH A BREAK IN THE RAIN LATER THURS AND THURS NIGHT. AS A REINFORCING SHORTWAVE IN THE 500 MB TROUGH ROUNDS THE BACK SIDE OF THE SYSTEM...IT IS PROJECTED TO BECOME CUT OFF AND LINGER ACROSS THE WESTERN GREAT LAKES THROUGH EARLY NEXT WEEK. THAT WOULD LIKELY KEEP RAIN SHOWER CHANCES ACROSS OUR AREA FOR MUCH OF THAT TIME...AS THE COLD POOL PROVIDES FAVORABLE LAPSE RATES FOR UPDRAFTS. SO A CHANGE FROM HEAT AND HUMIDITY TO CLOUDY AND COOLER APPEARS IN THE OFFING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
703 PM CDT MON JUN 24 2013 .DISCUSSION... ISSUED 300 PM CDT MON JUN 24 2013 THE SHORT TERM THROUGH WEDNESDAY WILL BE DOMINATED BY PERIODIC BOUTS OF SEVERE STORMS AND FLASH FLOODING...ALONG WITH HIGH HEAT AND HUMIDITY. A COLD FRONT SHOULD PUSH ACROSS ILLINOIS LATE IN THE WEEK PROVIDING SOME RELIEF FROM THE HEAT AND HUMIDITY AND DAILY THUNDERSTORMS. MUCH MORE COMFORTABLE CONDITIONS SHOULD DEVELOP NEXT WEEKEND. BASED ON THE 3-5" OF RAIN FROM PEORIA AND NORTH...WE DECIDED TO INCLUDE OUR NORTHERN 5 COUNTIES IN A FLASH FLOOD WATCH THROUGH TONIGHT DUE TO THE HEAVY RAIN POTENTIAL AGAIN. SHORT TERM...TONIGHT THROUGH WEDNESDAY. INITIAL SEVERE STORM WATCH IS IN EFFECT UNTIL 7 PM FOR OUR WESTERN COUNTIES BUT ANOTHER WATCH FOR AREAS NORTHEAST OF THAT WATCH MAY BE COMING SOON. BASED ON RADAR ANALYSIS...THE SOUTHERN END OF THE LINE OF STORMS IN N MO AND E IOWA APPEARS TO BE ERODING EARLY ON. WE COULD SEE ADDITIONAL DEVELOPMENT ON THE SOUTHERN FLANK AIDED BY INCREASING MID-LEVEL FLOW AND MOISTURE CONVERGENCE. IF NOT...THE SOUTHERN COUNTIES IN THE WATCH WILL NOT BE AFFECTED AS MUCH WITH THIS ROUND OF STORMS. CORFIDI VECTORS ARE SHOWING THE LINE SHOULD MAINTAIN ITS MOTION TO THE EAST-NORTHEAST AS IT MOVES ACROSS IL...WHICH WILL MAKE IT MU-CAPE VALUES ARE CLIMBING TO NEAR 3000 J/KG AS SUNSHINE AHEAD OF THE LINE HAS HELPED BOOST SURFACE TEMPERATURES INTO THE UPPER 80S WITH SURFACE DEWPOINTS IN THE LOWER 70S. SURFACE BASED CONVECTION WILL AID IN DOWNBURST WINDS BEING ABLE TO REACH THE GROUND. SPC MESO-ANALYSIS SHOWS DOWNBURST CAPE VALUES AROUND 1100 J/KG...WHICH ALSO POINTS TOWARD EFFICIENT MOMENTUM TRANSFER TO THE SURFACE AND DAMAGING WINDS. WITH VGP ABOVE 0.2 ACROSS OUR NORTHERN COUNTIES...WE COULD SEE SOME ROTATING EMBEDDED SUPERCELLS WITH A TORNADO POSSIBLE. THE LINE OF STORMS SHOULD REACH OUR WESTERN COUNTIES AROUND 4 PM...AND PROGRESS EASTWARD TO NEAR BMI BY 6 PM AND INTO INDIANA BY 8-9 PM. STRATIFORM RAIN BEHIND THE LINE MAY LINGER FOR A FEW HOURS. SATELLITE IMAGES SHOW A WEAK SHORTWAVE IN THE WAKE OF THIS COMPLEX...SO A FEW ADDITIONAL THUNDERSTORMS MAY AFFECT OUR NW COUNTIES THROUGH MORNING. THEREFORE WE KEPT CHANCE POPS IN THE NW AFTER MIDNIGHT. ANOTHER ROUND OF SEVERE STORMS WILL BE POSSIBLE ON TUESDAY...MAINLY NORTH OF I-72/74-DANVILLE. WE ORIGINALLY HAD EXPECTED SOME UPPER LEVEL RIDGING TO PROVIDE A BREAK IN THE STORMS...AND WE STILL MAY SEE DRY CONDITIONS FOR MUCH OF THE DAY. HOWEVER...SPC HAS EXPANDED THE DAY 2 SLIGHT RISK FARTHER SOUTH TO INCLUDE A LARGE PORTION OF OUR FORECAST AREA...SO WE DECIDED TO ACKNOWLEDGE THE SEVERE POTENTIAL WITH SLIGHTLY HIGHER POPS. WE WILL HAVE A BETTER CHANCE OF BEING CAPPED TUES AS THE MID LEVELS WARM. HOWEVER...ISOLATED AREAS THAT DO BREAK THE CAP WILL HAVE A GREAT DEAL OF ML-CAPE FOR VIGOROUS UPDRAFTS. WE STILL MAINLY HAVE SLIGHT CHANCE POPS EXCEPT FOR NORTH OF I-74 WHERE WE WENT WITH CHANCE POPS. WEDNESDAY SHOULD SEE INCREASING BETTER DESTABILIZATION OF THE LOWER TROP AS THE UPPER RIDGE BEGINS TO BREAK DOWN IN RESPONSE TO A PROGRESSIVE TROUGH FROM CANADA. SURFACE HEAT AND HUMIDITY WILL REMAIN HIGH...BUT SUNSHINE MAY BE A BIT MORE LIMITED IF CONVECTION DEVELOPS EARLIER IN THE AFTERNOON. TUES AND WED WILL HAVE POTENTIAL FOR HEAT INDEX READINGS AROUND 100 IN MANY AREAS BASED ON THE AMOUNT OF SUNSHINE AND WHERE THE CIRRUS SHIELD DEVELOPS AHEAD OF CONVECTION. STILL...VERY UNCOMFORTABLE CONDITIONS. LONG TERM...THURSDAY THROUGH MONDAY. THE MODELS ALL SHOW A COLD FRONTAL PASSAGE AT SOME POINT BEGINNING LATE WED NIGHT OR THURSDAY...BUT THE ARRIVAL OF COLDER AIR DELAYED UNTIL FRIDAY INTO FRIDAY NIGHT AS A SECONDARY PUSH OF CANADIAN AIR OCCURS. WE MAY SEE A FEW SHOWERS OR STORMS IN THE EAST THURSDAY AS THE COLD FRONT DEPARTS...WITH A BREAK IN THE RAIN LATER THURS AND THURS NIGHT. AS A REINFORCING SHORTWAVE IN THE 500 MB TROUGH ROUNDS THE BACK SIDE OF THE SYSTEM...IT IS PROJECTED TO BECOME CUT OFF AND LINGER ACROSS THE WESTERN GREAT LAKES THROUGH EARLY NEXT WEEK. THAT WOULD LIKELY KEEP RAIN SHOWER CHANCES ACROSS OUR AREA FOR MUCH OF THAT TIME...AS THE COLD POOL PROVIDES FAVORABLE LAPSE RATES FOR UPDRAFTS. SO A CHANGE FROM HEAT AND HUMIDITY TO CLOUDY AND COOLER APPEARS IN THE OFFING. && .AVIATION... ISSUED 658 PM CDT MON JUN 24 2013 MOSTLY GENERIC FORECAST YET AGAIN WITH THE POOR MODEL HANDLING OF THE MCS TRAIN OVER THE REGION. ADJUSTING FORECAST IN THE SHORT TERM TO HANDLE THE SLOWLY DWINDLING CONVECTION. PRECIP HOLDING TOGETHER FOR CMI AND BMI...BUT HAVE PULLED MOST PRECIP FOR THE NEXT FEW HOURS. CONCERN FOR PRECIP CONTINUES THROUGH TOMORROW THOUGH MODELS ARE ALL OVER THE PLACE. MOST FAITH IN HRRR FOR NOW...WHICH HAS A MORE SCT SIGNATURE. KEEPING MENTION OF VCTS THROUGH TOMORROW WITH SCT CU AND BKN MID CLOUDS. VFR THROUGHOUT FOR NOW WITH EXCEPTION OF UNDER CONVECTION. ANY RAPID CLEARING IN THE SHORT TERM HOWEVER WILL UP THE RISK OF A VISBY DROP. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
421 PM CDT SUN JUN 23 2013 .DISCUSSION... 304 PM CDT SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY THANKS TO COLD POOLS FROM MORNING CONVECTION. THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET. REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO. SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH. AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR MOST AREAS. TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT. HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN. BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT. UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES. HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY. MDB && .HYDROLOGY... 304 PM CDT GAVE CONSIDERATION TO A FLASH FLOOD WATCH FOR THE WEST AND FAR SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. GIVEN FAIRLY LOW CONFIDENCE IN WHERE ORGANIZED CONVECTION WILL SET UP TONIGHT AND MONDAY WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE BETTER DEFINED. CURRENT ACTIVITY IS STILL MOVING FAIRLY STEADILY BUT 1-1.5 INCHES OF RAIN PER HOUR ARE POSSIBLE LOCALLY. WILL PASS THE CONCERN ABOUT A WATCH TO THE EVENING SHIFT. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * SOUTH/SOUTHWEST WINDS EXPECTING THROUGH THIS AFTERNOON...POSSIBLY BECOMING MORE SOUTHWEST AS OUTFLOW BOUNDARY APPROACHES FROM THE WEST. * SLIGHT POSSIBILITY FOR AN ISOLATED SHOWER LATE THIS AFTERNOON. * POSSIBILITY FOR A CONTINUED ACTIVE PERIOD WITH SEVERAL CHANCES FOR SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE TERMINALS TONIGHT THROUGH MONDAY AFTERNOON. RODRIGUEZ //DISCUSSION...UPDATED 18Z... VERY COMPLEX FORECAST PERIOD AS THE POTENTIAL FOR AN ACTIVE WEATHER PATTERN OVER THE TERMINALS REMAINS. DESPITE AN ABUNDANCE OF MOISTURE AND INSTABILITY ACROSS THE AREA...THERE IS A LACK OF ANY CLEAR GOOD FORCING MECHANISMS WITH PRECIP TRENDS LOW AT THIS TIME WITH MODEL GUIDANCE NOT TOO MUCH OF ANY HELP. ALTHOUGH IN THE NEAR TERM...CONTINUE TO MONITOR SOME FAIRLY WEAK MID LEVEL FEATURES AS WELL AS SEVERAL OUTFLOW BOUNDARIES PROPAGATING ACROSS THE REGION. WITH THESE FEATURES IN PLACE...THERE IS THE POSSIBILITY FOR SHOWERS OR EVEN AN ISOLATED THUNDERSTORM. ALTHOUGH DESPITE THE BOUNDARIES/MID LEVEL FEATURES...THE ORIENTATION AND WEAKNESS OF THEM SHOULD ONLY PROVIDE ISOLATED TO AT BEST WIDELY SCATTERED DEVELOPMENT THIS AFTERNOON WITH ANYTHING THAT DOES DEVELOP TO BE ON THE BRIEF SIDE. SO WITH THIS LOW COVERAGE/LOW CONFIDENCE OF THIS AT THIS TIME...HAVE OPTED TO LEAVE OUT ANY MENTION OF PRECIP AT THIS TIME. WILL ALSO NEED TO CONTINUE TO MONITOR THE POTENTIAL FOR UPSTREAM DEVELOPMENT LATER THIS EVENING TO POSSIBLY SHIFT EAST ACROSS THE TERMINALS LATER TONIGHT...AS ONCE AGAIN CONFIDENCE REMAINS LOW AT THIS POSSIBILITY. AS WAS MENTIONED ABOVE...SEVERAL FEATURES COULD MOVE ACROSS THE REGION ONCE AGAIN ON MONDAY WITH SHOWERS/THUNDERSTORMS ONCE AGAIN POSSIBLE. WITH CONTINUED LOW CONFIDENCE AT THIS TIME...HAVE ONCE AGAIN LEFT OUT ANY MENTION OF PRECIP. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION THROUGH THIS AFTERNOON...WITH LOW MEDIUM CONFIDENCE OF THE MORE SOUTHWEST DIRECTION WITH THE PASSAGE OF THE BOUNDARY. * LOW CONFIDENCE OF SHOWERS THIS AFTERNOON. * LOW CONFIDENCE WITH PRECIP/CONVECTIVE TRENDS THIS PERIOD. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT THROUGH FRIDAY...PERIODIC CHANCES OF TSRA. SATURDAY...MAINLY VFR. CHC OF SHOWERS. BEACHLER && .MARINE... 420 PM CDT A LARGE AREA OF HIGH PRESSURE EXTENDS FROM THE WESTERN ATLANTIC SOUTHWESTWARD ACROSS THE SOUTHEASTERN U.S. AND THE NORTHERN GULF OF MEXICO. THIS HIGH WILL BE MOVING ONLY VERY SLOWLY SOUTHEASTWARD TONIGHT THROUGH THURSDAY. LOW PRESSURE NEAR LAKE WINNIPEG WILL BE MOVING SLOWLY EASTWARD ACROSS ONTARIO...REACHING NEAR SOUTHERN JAMES BAY BY TUESDAY MORNING. THEN...AN AREA OF LOW PRESSURE STRETCHING FROM THE SOUTHERN CANADIAN PRAIRIE SOUTH ACROSS THE PLAINS WILL MOVE NORTHEAST DURING TUESDAY AND WEDNESDAY. WITH HIGH PRESSURE SITUATED FAR TO THE SOUTH THROUGH SOUTHEAST OF THE LAKE AND LOW PRESSURE FROM FAR WEST THROUGH NORTHWEST TONIGHT INTO THURSDAY...MODERATE TO FRESH WINDS WILL PERSIST OUT OF THE SOUTH TO SOUTHWEST. THIS PERSISTENT FLOW WILL KEEP VERY MOIST AIR ACROSS THE WESTERN GREAT LAKES REGION. WHILE MOST OF THE FOG HAD DISSIPATED ON NORTHERN LAKE MICHIGAN...WITH THE MOIST AIR AND COOL LAKE WATER FOG IS EXPECTED TO REDEVELOP TONIGHT AND BECOME DENSE IN AREAS. THE CURRENT DENSE FOG ADVISORY FOR NORTHERN LAKE MICHIGAN WILL LIKELY NEED TO BE EXTENDED INTO TUESDAY AND POSSIBLY WEDNESDAY AS THERE WILL BE NO CHANGE IN AIRMASS UNTIL A COLD FRONT PUSHES ACROSS THE LAKE DURING LATER WEDNESDAY AND WEDNESDAY NIGHT...SHIFTING WINDS TO OUT OF THE WEST. A SECONDARY COLD FRONT WILL MOVE ACROSS THE LAKE AND SHIFT WINDS TO OUT OF THE NORTHWEST DURING LATER THURSDAY AND THURSDAY NIGHT. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565 UNTIL 7 AM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
306 PM CDT SUN JUN 23 2013 .DISCUSSION... 304 PM CDT SHOWER/THUNDER CHANCES REMAIN THE BIGGEST FORECAST CHALLENGE FOLLOWED BY TEMPS WHICH MAY BE AFFECTED BY THE CONVECTION. AFTERNOON WATER VAPOR IMAGERY SHOWS ONE UPPER LEVEL LOW SPINNING OVER THE CENTRAL APPALACHIANS WHICH IS LOSING DEFINITION AS IS MOVES SLOWLY NORTHWARD. THE NEXT UPPER LOW IS SPINNING OVER THE SOUTHERN CANADIAN PRAIRIES WITH A TROUGH AXIS EXTENDING INTO THE DAKOTAS AND LIFTING NORTHEAST. THE UPPER FLOW IS LESS AMPLIFIED FURTHER SOUTH OF THE LOW ACROSS THE CENTRAL PLAINS BUT THERE ARE SEVERAL EMBEDDED WAVES THAT ARE TRANSLATING NORTHEAST AS WELL. THE NEXT UPPER LOW OF NOTE IS COMING ONSHORE OVER THE WEST COAST AND HELPING TO AMPLIFY A RIDGE OVER OREGON/WASHINGTON. ENERGY EMANATING FROM THIS TROUGH WILL BECOME A PLAYER IN OUR WEATHER LATER THIS WEEK. AT THE SURFACE...LOW PRESSURE IS POSITIONED OVER NORTHWEST MINNESOTA WITH WEAKER LOW PRESSURE SPREAD ACROSS THE PLAINS. A COOL FRONTAL BOUNDARY IS STRETCHED FROM THE MN LOW BUT HAS BECOME DIFFICULT TO IDENTIFY THANKS TO COLD POOLS FROM MORNING CONVECTION. THROUGH THIS EVENING...TOUGH FORECAST ONCE AGAIN IN TERMS OF CONVECTIVE POTENTIAL AND EVOLUTION THROUGH THE PERIOD. OUTFLOW BOUNDARY FROM EARLIER IOWA CONVECTION IS NOW PUSHING INTO THE WESTERN CWA TRIGGERING THUNDERSTORMS ALONG IT. A BETTER ORGANIZED COMPLEX OF STORMS HAS DEVELOPED FROM THE EARLIER CONVECTION BUT IS MOVING SOUTHEAST ACROSS NORTHERN MISSOURI INTO THE AXIS OF MUCH BETTER INSTABILITY AS WELL AS BETTER MID LEVEL MOISTURE ADVECTION. ADDITIONAL SCATTERED STORMS HAVE DEVELOPED OVER THE SOUTHERN CWA LIKELY IN BETTER CONJUNCTION WITH THE WEAKENING UPPER LOW OVER APPALACHIA. IN THE NEAR TERM...EXPECT THE OUTFLOW TO CONTINUE EASTWARD ACROSS THE CWA TRIGGERING SCATTERED STORMS THROUGH LATE AFTERNOON/EARLY EVENING. MESOANALYSIS SHOWS 2000+ J/KG OF MIXED LAYER CAPE OVER THE AREA SUPPORTING STRONG UPDRAFTS BUT DEEP LAYER SHEAR IS WEAK SO CORES SHOULD BE PRETTY PULSEY. LARGE HAIL AND LOCALLY HEAVY DOWNPOURS ARE THE MAIN CONCERN. GUSTY WINDS ARE ALSO POSSIBLE BUT RECENT AIRCRAFT SOUNDINGS FROM MDW DO NOT SHOW A TON OF DRY LOW LEVEL AIR AND RAP ANALYSIS OF DCAPE IS LOW AS WELL. WOULD EXPECT THAT THIS ACTIVITY WOULD WANE WITH SUNSET. REST OF TONIGHT AND MONDAY...ATTENTION TURNS TO ADDITIONAL CONVECTIVE POTENTIAL OVERNIGHT. WATER VAPOR SHOWS A WAVE OVER NE KS/NW MO WHICH APPEARS TO BE TURNING MORE EASTWARD IN THE LAST FEW SCANS. THIS IS LIKELY HELPING THE COMPLEX TAKING SHAPE OVER MO. SHORT TERM/HIGH RES GUIDANCE HAS BEEN ALL OVER THE PLACE WITH HOW CONVECTION EVOLVES THROUGH TONIGHT. THE MOIST SOUTHWESTERLY FLOW WILL CONTINUE ACROSS THE REGION TONIGHT AND THE EARLIER COLD FRONTAL BOUNDARY SEEMS TO BE DEVELOPING ONCE AGAIN ACROSS IOWA AS THE FLOW HAS SETTLED FROM EARLIER CONVECTION. THIS IS SUPPORTIVE OF NEW DEVELOPMENT TO THE WEST TONIGHT. THE OUTFLOW CURRENTLY WORKING INTO THE LOCAL AREA EXTENDS INTO WEST-CENTRAL ILLINOIS AND THERE ARE HINTS THAT THE SOUTHERN EXTENT OF IT AND LIKELY A BOUNDARY SET UP BY THE CURRENT COMPLEX MAY STALL OUT SOMEWHERE NOT FAR FROM THE SOUTHWESTERN CWA. IN ADDITION...THE KS/MO WAVE IS EXPECTED TO CROSS THIS SAME AREA TONIGHT WHICH IS ALSO EXPECTED TO BE IN AN AREA OF MID LEVEL WARM ADVECTION. THEREFORE IT IS POSSIBLE ROUNDS OF CONVECTION COULD DEVELOP TO THE SOUTHWEST OF THE AREA AND ROLL EASTWARD INTO THE SOUTHERN CWA OVERNIGHT. HAVE NOT MADE MUCH CHANGE TO OVERNIGHT POPS BUT DID INCREASE THEM SOMEWHAT OVER THE FAR SOUTH. AS FOR MONDAY...GUIDANCE REMAINS IN POOR AGREEMENT WITH TRACK OF POTENTIAL UPPER WAVES BUT WATER VAPOR DOES SHOW SOME SIGNS OF A WAVE COMING ACROSS THE FOUR CORNERS THIS AFTERNOON. THIS WOULD COME ACROSS THE REGION LATER MONDAY BUT IT IS NOT CLEAR IF IT WILL BE MORE FOCUSED TO THE NORTH OF THE AREA. WILL CONTINUE WITH MID CHANCE POPS WITH LATER IN THE DAY MORE FAVORED. PROVIDED THE LATER TIMING WORKS OUT THEN WE WILL HAVE A BETTER CHANCE TO WARM BUT THERE MAY BE CONVECTIVE DEBRIS AROUND SO WILL HOLD TEMPS INTO THE MID 80S FOR MOST AREAS. TUESDAY THROUGH SUNDAY...THE UPPER FLOW BECOMES LESS AMPLIFIED TUESDAY BUT WILL LIKELY STILL BE LITTERED WITH WAVES TRAVERSING IT. HOT AND HUMID AIR WILL STILL BE IN PLACE WITH PRECIPITABLE WATER VALUES HOVERING AROUND 1.75 INCHES. THESE FACTORS PROVIDE CONTINUED SUPPORT FOR THUNDERSTORM DEVELOPMENT BUT THERE IS NOT MUCH TO KEY IN ON FOR A COHERENT FORCING MECHANISM GIVEN THE LOW AMPLITUDE PATTERN. BY WEDNESDAY...THERE IS SOME AGREEMENT ON SURFACE LOW PRESSURE HAVING DEVELOPED ACROSS THE CANADIAN PRAIRIES WITH A TROUGH AXIS/FRONT EXTENDING INTO MINNESOTA AND IOWA...WITH A SECONDARY LOW POSSIBLY DEVELOPING ACROSS MINNESOTA. THE FRONT LOOKS TO CROSS THE AREA LATER WEDNESDAY BRINGING SHOWER AND STORM CHANCES WITH IT. UPPER RIDGING WILL BE BUILDING ACROSS THE WESTERN U.S. AND HIGH PLAINS WITH A WAVE ORIGINATING FROM THE TROUGH OFF THE WEST COAST OVERTOPPING THE RIDGE ACROSS THE CANADIAN ROCKIES AND DROPPING SOUTHEASTWARD INTO THE GREAT LAKES WHILE AMPLIFYING LATE IN THE WEEK. GFS AND ECMWF DIFFER ON HOW QUICKLY THIS OCCURS BUT THE SIGNAL HAS BEEN CONSISTENT OVERALL. THIS WILL BRING A SHIFT TO NORTHWESTERLY AT THE SURFACE AND ALOFT LATE IN THE WEEK AND NOTICEABLY COOLER TEMPERATURES BY SATURDAY OR SO. LOW POPS WILL CONTINUE WITH THE FLOW CONTINUING TO FAVOR WEAK SHORTWAVE PASSAGES. HIGH TEMPS WILL LIKELY HOVER AROUND 90 TUESDAY AND WEDNESDAY ASSUMING CONVECTION OR CONVECTIVE DEBRIS IS NOT AN ISSUE...WHICH WOULD SIGNIFICANTLY LOWER HIGHS IF IT IS. WITH THE PASSAGE OF THE SYSTEM LATER WEDNESDAY COOLER MID LEVEL AIR WILL FILTER IN KEEPING HIGHS BACK IN THE 80S WITH UPPER 70S POSSIBLE FRIDAY AND SATURDAY. MDB && .HYDROLOGY... 304 PM CDT GAVE CONSIDERATION TO A FLASH FLOOD WATCH FOR THE WEST AND FAR SOUTHWEST CWA GIVEN THE RAINFALL OF THE PAST FEW DAYS. GIVEN FAIRLY LOW CONFIDENCE IN WHERE ORGANIZED CONVECTION WILL SET UP TONIGHT AND MONDAY WILL HOLD OFF UNTIL AREAS AND TIMING CAN BE BETTER DEFINED. CURRENT ACTIVITY IS STILL MOVING FAIRLY STEADILY BUT 1-1.5 INCHES OF RAIN PER HOUR ARE POSSIBLE LOCALLY. WILL PASS THE CONCERN ABOUT A WATCH TO THE EVENING SHIFT. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * SOUTH/SOUTHWEST WINDS EXPECTING THROUGH THIS AFTERNOON...POSSIBLY BECOMING MORE SOUTHWEST AS OUTFLOW BOUNDARY APPROACHES FROM THE WEST. * SLIGHT POSSIBILITY FOR AN ISOLATED SHOWER LATE THIS AFTERNOON. * POSSIBILITY FOR A CONTINUED ACTIVE PERIOD WITH SEVERAL CHANCES FOR SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE TERMINALS TONIGHT THROUGH MONDAY AFTERNOON. RODRIGUEZ //DISCUSSION...UPDATED 18Z... VERY COMPLEX FORECAST PERIOD AS THE POTENTIAL FOR AN ACTIVE WEATHER PATTERN OVER THE TERMINALS REMAINS. DESPITE AN ABUNDANCE OF MOISTURE AND INSTABILITY ACROSS THE AREA...THERE IS A LACK OF ANY CLEAR GOOD FORCING MECHANISMS WITH PRECIP TRENDS LOW AT THIS TIME WITH MODEL GUIDANCE NOT TOO MUCH OF ANY HELP. ALTHOUGH IN THE NEAR TERM...CONTINUE TO MONITOR SOME FAIRLY WEAK MID LEVEL FEATURES AS WELL AS SEVERAL OUTFLOW BOUNDARIES PROPAGATING ACROSS THE REGION. WITH THESE FEATURES IN PLACE...THERE IS THE POSSIBILITY FOR SHOWERS OR EVEN AN ISOLATED THUNDERSTORM. ALTHOUGH DESPITE THE BOUNDARIES/MID LEVEL FEATURES...THE ORIENTATION AND WEAKNESS OF THEM SHOULD ONLY PROVIDE ISOLATED TO AT BEST WIDELY SCATTERED DEVELOPMENT THIS AFTERNOON WITH ANYTHING THAT DOES DEVELOP TO BE ON THE BRIEF SIDE. SO WITH THIS LOW COVERAGE/LOW CONFIDENCE OF THIS AT THIS TIME...HAVE OPTED TO LEAVE OUT ANY MENTION OF PRECIP AT THIS TIME. WILL ALSO NEED TO CONTINUE TO MONITOR THE POTENTIAL FOR UPSTREAM DEVELOPMENT LATER THIS EVENING TO POSSIBLY SHIFT EAST ACROSS THE TERMINALS LATER TONIGHT...AS ONCE AGAIN CONFIDENCE REMAINS LOW AT THIS POSSIBILITY. AS WAS MENTIONED ABOVE...SEVERAL FEATURES COULD MOVE ACROSS THE REGION ONCE AGAIN ON MONDAY WITH SHOWERS/THUNDERSTORMS ONCE AGAIN POSSIBLE. WITH CONTINUED LOW CONFIDENCE AT THIS TIME...HAVE ONCE AGAIN LEFT OUT ANY MENTION OF PRECIP. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION THROUGH THIS AFTERNOON...WITH LOW MEDIUM CONFIDENCE OF THE MORE SOUTHWEST DIRECTION WITH THE PASSAGE OF THE BOUNDARY. * LOW CONFIDENCE OF SHOWERS THIS AFTERNOON. * LOW CONFIDENCE WITH PRECIP/CONVECTIVE TRENDS THIS PERIOD. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT THROUGH FRIDAY...PERIODIC CHANCES OF TSRA. SATURDAY...MAINLY VFR. CHC OF SHOWERS. BEACHLER && .MARINE... 326 AM CDT BROAD RIDGE OF HIGH PRESSURE REMAINS ANCHORED ACROSS THE WESTERN ATLANTIC OCEAN STRETCHING NORTH THROUGH QUEBEC. A TROUGH OF LOW PRESSURE OVER THE CENTRAL PLAINS WILL LIFT NORTH INTO ALBERTA...THEN SLOWLY SLIDE EAST ACROSS CENTRAL ONTARIO MONDAY WITH A TRAILING FRONTAL BOUNDARY SAGGING SOUTH ACROSS MID LAKE MONDAY. THIS FRONTAL BOUNDARY WILL THEN STRETCH WEST THROUGH CENTRAL IOWA...AS ANOTHER AREA OF LOW PRESSURE WILL DEVELOP ACROSS THE CENTRAL PLAINS AND SLOWLY SLIDE NORTHEAST TOWARDS THE UPPER MIDWEST WEDNESDAY NIGHT INTO THURSDAY. AT TIMES WINDS WILL BECOME GUSTY THIS AFTERNOON TO 20-25KT...HOWEVER WITH THE VERY WARM/MOIST AIR FLOWING OVER THE COOLER LAKE THIS MAY HOLD GUSTS DOWN ARND 20KT. THE OTHER CONCERN FOR TODAY/TONIGHT AND THROUGH MONDAY WILL BE ON FOG. IT DOES APPEAR THAT PATCHY DENSE FOG WILL HOVER OVER THE LAKE...MAINLY THE NORTHERN HALF AGAIN TODAY THROUGH TONIGHT. HOWEVER WITH A CONTINUED FEED OF WIND...IT DOES NOT APPEAR FAVORABLE FOR WIDESPREAD DENSE FOG AT THIS TIME. SO HAVE OPTED TO KEEP MENTION AS PATCHY DENSE FOG. WINDS WILL REMAIN SOUTHERLY THROUGH THE NEXT SEVERAL DAYS...UNTIL A PATTERN CHANGE DEVELOPS LATE IN THE UPCOMING WEEK. THEN WINDS WILL BEGIN TO SHIFT WEST/NORTHWEST TOWARDS FRIDAY/SATURDAY. BEACHLER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565 UNTIL 7 AM MONDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
103 PM CDT SUN JUN 23 2013 .DISCUSSION... ISSUED 1027 AM CDT SUN JUN 23 2013 CURRENT CONVECTION OVER SOUTHEAST CWA FIRING OFF LEFTOVER BOUNDARIES FROM YESTERDAYS STORMS AND LIFT OFF WESTERN FRINGE OF CLOSED MID LEVEL LOW CENTERED OVER KY. THIS OCCURRING IN A VERY HIGH 1.8 P/W AIRMASS AND WEAK WINDS ALOFT SO STORMS ARE SLOW MOVERS AND POSE A HEAVY RAIN THREAT. HI-RES MODELS GRADUALLY PUSH THIS AREA EAST AFFECTING MUCH OF SE IL THROUGH MID AFTERNOON. OTHER AREA OF CONCERN IS LINE OF STORMS SHIFTING THROUGH CENTRAL IA WHICH HAS SHOWN RECENT CLOUD TOP COOLING ON IR SAT IMAGERY. IF THIS HOLDS TOGETHER LIKELY WOULDNT REACH WESTERN CWA UNTIL EVENING. HOWEVER OUTFLOW PUSHING AHEAD OF THIS ALREADY INTO EASTERN IA EVIDENT ON KDVN REFLECTIVITY IMAGERY. AWIPS DISTANCE SPEED TOOL BRINGS THIS INTO KNOX CO NEAR NOON AND WILL NEED TO MONITOR NEW CONVECTION POSSIBLY FIRING ALONG/BEHIND THIS AS HAS OCCURRED IN CWA PAST TWO DAYS. AIRMASS SHOWS LITTLE CHANGE FROM YESTERDAY WITH HIGH P/W WEAK WINDS ALOFT AND MODERATE INSTABILITY. THEREFORE HEAVY RAIN REMAINS PRIMARY THREAT THROUGH BULK SHEAR INCREASES TO 30 KTS THIS AFTERNOON ACROSS THE WESTERN HALF AND WOULD GIVE SOME ORGANIZATION FOR A LOW END SVR WIND AND HAIL THREAT. HAVE INCREASED POPS TO LIKELY OVER THE SOUTHEAST INTO EARLY AFTERNOON...THEN HAVE CHANCE POPS OVER REMAINDER OF CWA WITH HIGHEST CHANCES OVER THE WEST. HIGHS WILL AGAIN REACH THE LOWER 90S IN AREAS THAT SEE MORE SUN AND WITH DEWPOINTS AROUND 70 PEAK HEAT INDICES WILL BE IN THE UPPER 90S. && .AVIATION... ISSUED 102 PM CDT SUN JUN 23 2013 ISOLATED THUNDERSTORMS BEGINNING TO DEVELOP AS CONVECTIVE TEMPS ARE REACHED THIS AFTERNOON AND HAVE VCTS UNTIL 02Z. A BETTER CHANCE FOR STORMS MID AFTERNOON INTO EARLY EVENING AS COMPLEX CURRENTLY PUSHING INTO EASTERN IA MOVES ACROSS CENTRAL IL. LATEST RUN OF HI-RES MODELS INDICATES THIS AFFECTING CENTRAL IL TERMINALS BEGINNING AT 20Z AT KPIA AND EXITING KCMI AROUND 02Z. TEMPO VSBY REDUCTIONS AND MVFR CEILINGS DURING THIS TIMEFRAME. ISOLATED HEAVIER CELLS COULD BRING IFR CEILINGS/VSBYS AND GUSTY VARIABLE WINDS FOR A BRIEF TIME. AFTER THIS ACTIVITY SHIFTS EAST THIS EVENING...LOW CONFIDENCE IN REDEVELOPMENT OVERNIGHT WITH HIGHER CHANCES TO OUR WEST. SOUTHWEST WINDS GUSTING AROUND 20 KTS THIS AFTERNOON WILL SUBSIDE TO UNDER 10 KTS AFTER O2Z...THEN PICK UP TO 10-15 KTS AFTER 14Z/MON. 25 && .PREV DISCUSSION... ISSUED 230 AM CDT SUN JUN 23 2013 SHORT TERM...TODAY THROUGH TUESDAY... PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND 700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY. OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST... WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO THE MID-MISSISSIPPI VALLEY. TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON. LONG TERM...WEDNESDAY THROUGH SATURDAY... SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH AN ASSOCIATED SURFACE BOUNDARY. AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND. THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY COMPLICATE THIS THINKING. GEELHART && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1028 AM CDT SUN JUN 23 2013 .DISCUSSION... ISSUED 1027 AM CDT SUN JUN 23 2013 CURRENT CONVECTION OVER SOUTHEAST CWA FIRING OFF LEFTOVER BOUNDARIES FROM YESTERDAYS STORMS AND LIFT OFF WESTERN FRINGE OF CLOSED MID LEVEL LOW CENTERED OVER KY. THIS OCCURRING IN A VERY HIGH 1.8 P/W AIRMASS AND WEAK WINDS ALOFT SO STORMS ARE SLOW MOVERS AND POSE A HEAVY RAIN THREAT. HI-RES MODELS GRADUALLY PUSH THIS AREA EAST AFFECTING MUCH OF SE IL THROUGH MID AFTERNOON. OTHER AREA OF CONCERN IS LINE OF STORMS SHIFTING THROUGH CENTRAL IA WHICH HAS SHOWN RECENT CLOUD TOP COOLING ON IR SAT IMAGERY. IF THIS HOLDS TOGETHER LIKELY WOULDNT REACH WESTERN CWA UNTIL EVENING. HOWEVER OUTFLOW PUSHING AHEAD OF THIS ALREADY INTO EASTERN IA EVIDENT ON KDVN REFLECTIVITY IMAGERY. AWIPS DISTANCE SPEED TOOL BRINGS THIS INTO KNOX CO NEAR NOON AND WILL NEED TO MONITOR NEW CONVECTION POSSIBLY FIRING ALONG/BEHIND THIS AS HAS OCCURRED IN CWA PAST TWO DAYS. AIRMASS SHOWS LITTLE CHANGE FROM YESTERDAY WITH HIGH P/W WEAK WINDS ALOFT AND MODERATE INSTABILITY. THEREFORE HEAVY RAIN REMAINS PRIMARY THREAT THROUGH BULK SHEAR INCREASES TO 30 KTS THIS AFTERNOON ACROSS THE WESTERN HALF AND WOULD GIVE SOME ORGANIZATION FOR A LOW END SVR WIND AND HAIL THREAT. HAVE INCREASED POPS TO LIKELY OVER THE SOUTHEAST INTO EARLY AFTERNOON...THEN HAVE CHANCE POPS OVER REMAINDER OF CWA WITH HIGHEST CHANCES OVER THE WEST. HIGHS WILL AGAIN REACH THE LOWER 90S IN AREAS THAT SEE MORE SUN AND WITH DEWPOINTS AROUND 70 PEAK HEAT INDICES WILL BE IN THE UPPER 90S. 25 && .AVIATION... ISSUED 532 AM CDT SUN JUN 23 2013 COVERAGE OF CONVECTION THIS PERIOD AND ITS AFFECT ON CIGS/VSBYS THE MAIN FORECAST CHALLENGE. REMNANT CONVECTIVELY INDUCED VORT MAX OVER SOUTH CENTRAL IL THIS MORNING TRYING TO KICK OFF SOME MORE SHOWERS AND THUNDERSTORMS OVER SE AND SRN IL...SOUTH OF OUR TAF SITES. EXPECT THAT AREA TO FILL IN LATER THIS MORNING...POSSIBLY AFFECT KCMI AFTR 15Z. ADDITIONAL CONVECTION WILL BE POSSIBLE ACRS THE WEST LATER THIS AFTN AS STORMS ACRS IOWA RE-ITENSIFY JUST WEST OF THE MISSISSIPPI RIVER AND THEN HEAD EAST. SOME OF THE MODELS TRY TO CURE THOSE STORMS MORE TO THE SE WHILE OPERATIONAL MODELS SUGGEST MORE OF AN EASTWARD TRACK WHICH WOULD INCLUDE ALL OF OUR SITES LATE THIS AFTN AND EARLY THIS EVENING. WILL STILL INCLUDE VCTS DURING THE TIME FRAME WE THINK THE STORMS WILL BE MOVING THRU...AND THEN ONCE CONFIDENCE INCREASES WITH RESPECT TO TIMING AND COVERAGE...WE WOULD THEN BE ABLE TO PIN DOWN A TIME FRAME FOR A TEMPO GROUP. AWAY FROM THE SHOWERS AND TSRA...WE CAN EXPECT VFR CONDITIONS...BUT ANY TAF AREA THAT SEES THE PRECIP MAY EXPERIENCE SOME BRIEF MVFR AND LOCALLY IFR CIGS AND VSBYS IN SOME OF THE HEAVIER PRECIP. SFC WINDS WILL REMAIN OUT OF THE SOUTH TODAY WITH SPEEDS OF 10 TO 15 KTS WITH OCCASIONAL GUSTS UP TO 20 KTS BEFORE WINDS DIMINISH TO AROUND 10 KTS THIS EVENING. SMITH && .PREV DISCUSSION... ISSUED 230 AM CDT SUN JUN 23 2013 SHORT TERM...TODAY THROUGH TUESDAY... PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND 700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY. OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST... WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO THE MID-MISSISSIPPI VALLEY. TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON. LONG TERM...WEDNESDAY THROUGH SATURDAY... SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH AN ASSOCIATED SURFACE BOUNDARY. AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND. THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY COMPLICATE THIS THINKING. GEELHART && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
538 AM CDT SUN JUN 23 2013 .DISCUSSION... ISSUED 230 AM CDT SUN JUN 23 2013 SHORT TERM...TODAY THROUGH TUESDAY... PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND 700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY. OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST... WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO THE MID-MISSISSIPPI VALLEY. TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON. LONG TERM...WEDNESDAY THROUGH SATURDAY... SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH AN ASSOCIATED SURFACE BOUNDARY. AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND. THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY COMPLICATE THIS THINKING. GEELHART && .AVIATION... ISSUED 532 AM CDT SUN JUN 23 2013 COVERAGE OF CONVECTION THIS PERIOD AND ITS AFFECT ON CIGS/VSBYS THE MAIN FORECAST CHALLENGE. REMNANT CONVECTIVELY INDUCED VORT MAX OVER SOUTH CENTRAL IL THIS MORNING TRYING TO KICK OFF SOME MORE SHOWERS AND THUNDERSTORMS OVER SE AND SRN IL...SOUTH OF OUR TAF SITES. EXPECT THAT AREA TO FILL IN LATER THIS MORNING...POSSIBLY AFFECT KCMI AFTR 15Z. ADDITIONAL CONVECTION WILL BE POSSIBLE ACRS THE WEST LATER THIS AFTN AS STORMS ACRS IOWA RE-ITENSIFY JUST WEST OF THE MISSISSIPPI RIVER AND THEN HEAD EAST. SOME OF THE MODELS TRY TO CURE THOSE STORMS MORE TO THE SE WHILE OPERATIONAL MODELS SUGGEST MORE OF AN EASTWARD TRACK WHICH WOULD INCLUDE ALL OF OUR SITES LATE THIS AFTN AND EARLY THIS EVENING. WILL STILL INCLUDE VCTS DURING THE TIME FRAME WE THINK THE STORMS WILL BE MOVING THRU...AND THEN ONCE CONFIDENCE INCREASES WITH RESPECT TO TIMING AND COVERAGE...WE WOULD THEN BE ABLE TO PIN DOWN A TIME FRAME FOR A TEMPO GROUP. AWAY FROM THE SHOWERS AND TSRA...WE CAN EXPECT VFR CONDITIONS...BUT ANY TAF AREA THAT SEES THE PRECIP MAY EXPERIENCE SOME BRIEF MVFR AND LOCALLY IFR CIGS AND VSBYS IN SOME OF THE HEAVIER PRECIP. SFC WINDS WILL REMAIN OUT OF THE SOUTH TODAY WITH SPEEDS OF 10 TO 15 KTS WITH OCCASIONAL GUSTS UP TO 20 KTS BEFORE WINDS DIMINISH TO AROUND 10 KTS THIS EVENING. SMITH && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
231 AM CDT SUN JUN 23 2013 .DISCUSSION... ISSUED 230 AM CDT SUN JUN 23 2013 SHORT TERM...TODAY THROUGH TUESDAY... PROBLEMATIC FORECAST CONTINUES FOR THE NEXT FEW DAYS IN REGARDS TO CONVECTIVE DEVELOPMENT. EVENTS OF THE LAST COUPLE DAYS HAVE SHOWN HOW LEFTOVER BOUNDARIES LEAD TO REDEVELOPMENT IN THE HEAT OF THE DAY...AND ANOTHER SUCH BOUNDARY IS DROPPING SOUTHWARD THROUGH FAR NORTHERN ILLINOIS...FORMED BY A DECAYING MCS OVER WISCONSIN AND SOUTHEAST MINNESOTA. SOME WEAK BOUNDARIES ALSO DETECTED OVER SOUTHEAST ILLINOIS LOOPING WESTWARD INTO AREAS SOUTHWEST OF SAINT LOUIS. STORMS THAT FORM TODAY SHOULD BE VERY EFFICIENT RAIN MAKERS AGAIN...AS PRECIPITABLE WATER VALUES WILL BE AROUND 1.7 INCHES AND 700 MB WINDS OF LESS THAN 10 KNOTS INDICATE THE STORMS WILL BE IN NO HURRY TO MOVE ONCE THEY FORM. LATEST RAP AND HRRR MODELS SHOW SOME DEVELOPMENT TAKING PLACE AS EARLY AS SUNRISE NEAR THE SOUTHERN OUTFLOW...AND AFTERNOON DEVELOPMENT SHOULD ACCOMPANY THE NORTHERN BOUNDARY. HAVE GONE A LITTLE MORE AGGRESSIVE WITH THE POPS AS A RESULT WITH 30-40 PERCENT MOST AREAS TODAY. OVERNIGHT PROBLEM THEN SHIFTS TO TRACK OF THE NEXT MCS WHICH SHOULD FORM OVER IOWA THIS EVENING. NAM AND GFS ARE MORE PROGRESSIVE WITH SPREADING IT OVER MUCH OF ILLINOIS BY EARLY MONDAY MORNING...WHILE THE LATEST ECMWF IS SLOWER AND SHUNTS MOST OF IT OFF TO OUR NORTH. LEANING TOWARD A MORE SOUTHERN SOLUTION AT THE MOMENT WITH 40-50 PERCENT POPS FROM ABOUT I-55 NORTHWEST... WITH MAINLY SLIGHT CHANCES ACROSS THE SOUTHEAST. ONCE THIS PARTICULAR MCS EXITS ON MONDAY...THE STORM TRACK FOR THE NEXT ROUND SHIFTS A BIT FURTHER NORTH AS SOME UPPER RIDGING BUILDS INTO THE MID-MISSISSIPPI VALLEY. TEMPERATURE-WISE...STILL LOOKING LIKE 90 DEGREES OR A BIT HIGHER IS LIKELY THE NEXT FEW DAYS...PROVIDED THE STORMS DO NOT GET OUT OF CONTROL. SLOW BUILD OF THE DEW POINTS TOWARD THE MID 70S WILL RESULT IN HEAT INDEX VALUES A FEW DEGREES HIGHER EACH DAY...WITH MOST AREAS JUST ABOVE 100 FOR HEAT INDEX BY TUESDAY AFTERNOON. LONG TERM...WEDNESDAY THROUGH SATURDAY... SUMMER-TIME PATTERN TO CONTINUE THROUGH MID WEEK. MAIN STORM TRACK WILL BE ACROSS THE NORTH CENTRAL STATES...WITH SOME POTENTIAL FOR SHOWERS/STORMS FURTHER SOUTH AS THE OUTFLOWS FROM THE NIGHTLY MCS SYSTEMS DROP INTO OUR AREA. BEST CHANCE OF RAIN WILL PROBABLY BE WEDNESDAY NIGHT...AS A SHORTWAVE DROPS INTO THE MIDWEST ALONG WITH AN ASSOCIATED SURFACE BOUNDARY. AS THE END OF THE WEEK PROGRESSES...UPPER LEVEL RIDGING WILL BUILD ACROSS THE ROCKIES...WITH A NORTHWEST FLOW BRINGING COOLER CONDITIONS TO THE MIDWEST FOR FRIDAY AND ESPECIALLY THE WEEKEND. THINK MOST OF THE RAIN THREAT WILL BE OUT OF THE AREA BY THURSDAY EVENING...BUT WEAK TROUGHS ROTATING THROUGH THE MIDWEST MAY COMPLICATE THIS THINKING. GEELHART && .AVIATION... ISSUED 1201 AM CDT SUN JUN 23 2013 SOME SHIFTS IN THE FORECAST AS DEC CMI AND BMI ALL DROPPING TEMPS CLOSE TO DWPTS AND INCREASING CHANCE FOR AT LEAST MVFR VIS. HRRR AND 4KM WRF BOTH SHOWING ENOUGH SCT SHOWERS TO START THE TREND FOR TOMORROW STARTING IN THE 16-18Z TIME FRAME. MAY NEED TO CONVERT TO THUNDER SHOULD THE TREND CONTINUE. SOUTHERLY FLOW THROUGH THE OVERNIGHT...WILL BE A BIT OF AN ISSUE FOR FG DEVELOPMENT. GETTING GUSTY AGAIN TOMORROW AND TAKING ON A BIT OF A SWRLY COMPONENT. SCATTERING CLOUDS BACK OUT AFTER SUNSET TOMORROW. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
635 PM CDT MON JUN 24 2013 ...UPDATED FOR AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 353 PM CDT MON JUN 24 2013 A FAIRLY STRONG SHORTWAVE TROUGH BY LATE JUNE STANDARDS WAS APPROACHING THE SOUTHERN AND CENTRAL HIGH PLAINS THIS AFTERNOON. AHEAD OF THIS FEATURE, STRONG SURFACE TROUGH HAD DEVELOPED OVER THE HIGH PLAINS, WITH STRONG SOUTHERLY WINDS ACROSS SOUTHWEST KANSAS. ELEVATED CONVECTION IN ADVANCE OF THIS SYSTEM DEVELOPED THIS MORNING EAST OF DODGE CITY AND THEN MOVED EAST AND WEAKENED. ANOTHER BATCH OF ELEVATED CONVECTION DEVELOPED WEST OF A SURFACE DRYLINE IN SOUTHEAST COLORADO AND MOVED INTO FAR SOUTHWEST KANSAS THIS AFTERNOON. SURFACE BASED CONVECTION HAD NOT YET DEVELOPED AS OF 3 PM. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 353 PM CDT MON JUN 24 2013 THE SHORT RANGE HRRR DOES INDICATE STORMS DEVELOPING IN THE TEXAS AND OKLAHOMA PANHANDLES THIS AFTERNOON AS UPPER LEVEL FORCING AIDS IN LOW LEVEL CONVERGENCE ALONG THE DRYLINE. GIVEN THE FAIRLY STRONG MID LEVEL FLOW FROM THE SOUTHWEST, THIS CONVECTION SHOULD MOVE NORTHEASTWARD FAIRLY RAPIDLY INTO SOUTHWEST KANSAS THIS EVENING. SURFACE BASED CAPE VALUES WERE APPROACHING 3000 J/KG FROM THE TEXAS PANHANDLE INTO SOUTHWEST KANSAS AHEAD OF THE DRYLINE. 0-6 KM BULK SHEAR WAS APPROACHING 40 KTS IN THIS SAME AREA, BUT LOW LEVEL SHEAR WAS VERY WEAK. GIVEN THE EXPECTED HIGH DEWPOINT DEPRESSIONS AND RESULTANT HIGH CLOUD BASES, THE STORMS MAY DEVELOP QUITE A BIT OF OUTFLOW, AND THIS MAY LIMIT THE SEVERITY AS FAR AS HAIL SIZE IS CONCERNED (SINCE THE STORMS MAY NOT REMAIN AS SUPERCELL STRUCTURES AS LONG). BUT HAIL AS LARGE AS GOLFBALLS IS POSSIBLE WITH THE STRONGEST STORMS. IT IS UNCLEAR HOW ORGANIZED THE STORMS WILL BE AND HOW WIDESPREAD AND HEAVY THE RESULTANT RAINFALL WOULD BE. BUT STORM CHANCES WERE INCREASED TO 30-40% FOR PARTS OF SOUTHWEST KANSAS INCLUDING DODGE CITY, JETMORE AND LARNED GIVEN THE SIGNIFICANT FORCING AND SURFACE BASED CAPE. AFTER THE AFOREMENTIONED SHORTWAVE TROUGH PASSES TONIGHT AND WITH THE LOSS OF DAYTIME HEATING, STORM CHANCES WILL DIMINISH RAPIDLY BY LATE EVENING. THE LOW LEVEL WINDS WILL BEGIN TO VEER AS WELL AND THIS WILL RESULT IN THE AXIS OF DEEP MOISTURE SHIFTING EASTWARD. SOUTHWEST WINDS AT 15 KTS EVEN LATE TONIGHT WILL PREVENT TEMPERATURES FROM DROPPING BELOW THE LOWER 70S AT DODGE CITY, HAYS AND PRATT, WITH ONLY SLIGHTLY COOLER READINGS NEAR THE COLORADO BORDER. BEHIND THE SHORTWAVE TROUGH, A WEAK COLD FRONT WILL PROGRESS INTO CENTRAL KANSAS TUESDAY AFTERNOON, WITH A TRAILING DRYLINE EAST OF DODGE CITY AND INTO THE PANHANDLES. VERY HOT TEMPERATURES FROM 103 TO 106F ARE EXPECTED IMMEDIATELY BEHIND THE DRYLINE WHERE THE LOW LEVEL AIR HAS MOVED DOWNSLOPE AND WARMED ADIABATICALLY. ONLY SLIGHTLY COOLER AIR CAN BE EXPECTED IN FAR WESTERN KANSAS ON THE HIGHER TERRAIN, AND BEHIND THE WEAK COLD FRONT FROM WAKEENEY TO DIGHTON. THUNDERSTORMS ARE NOT EXPECTED TUESDAY AFTERNOON GIVEN THE LACK OF FORCING IN THE WAKE OF THE SHORTWAVE TROUGH AND SINCE THE LOW LEVEL MOIST AXIS WILL HAVE SHIFTED FURTHER EAST BY THE TIME OF PEAK HEATING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 336 PM CDT MON JUN 24 2013 ZONAL FLOW ALOFT WILL BE IN PLACE OVER THE LOWER 48 STATES AT THE BEGINNING OF THE EXTENDED PERIOD. A SHORTWAVE TROUGH THAT IS NOW MOVING THROUGH THE GREAT BASIN AND DESERT SOUTHWEST WILL BE EXITING THE NORTHERN AND CENTRAL PLAINS TUESDAY EVENING. THIS SYSTEM WILL BRING A WEAK FRONTAL BOUNDARY SOUTH ACROSS WESTERN KANSAS IN ITS WAKE LATE TUESDAY AFTERNOON AND EVENING. PRECIPITATION CHANCES LOOK FAIRLY SMALL GIVEN THE LACK OF UPPER SUPPORT AND A FAIRLY DRY AIRMASS. THROUGH THE MIDDLE PART OF THE WEEK, 500 MILLIBAR HEIGHTS WILL BE BUILDING OVER THE WESTERN AND CENTRAL PART OF THE COUNTRY. WITH INCREASING THICKNESS VALUES OVER WESTERN KANSAS WE SHOULD SEE DAYTIME HIGH TEMPERATURES WARMING BACK UP TO AROUND OR ABOVE 100 DEGREES ESPECIALLY BY THURSDAY. THE UPPER RIDGE BECOMES MORE AMPLIFIED OVER WESTERN NORTH AMERICA TOWARD THE UPCOMING WEEKEND WITH UPPER LEVEL FLOW BECOMING MORE NORTHWESTERLY OVER THE CENTRAL PLAINS. A WEAK FRONTAL BOUNDARY IS FORECAST TO MOVE SOUTH THROUGH THE CENTRAL HIGH PLAINS EARLY FRIDAY WITH EASTERLY UPSLOPE FLOW SETTING UP INTO THE EASTERN SLOPES OF THE ROCKIES. AFTERNOON THUNDERSTORMS SHOULD DEVELOP OFF THE FRONT RANGE. GIVEN THE UPPER LEVEL FLOW, SOME OF THESE COULD MOVE INTO FAR WESTERN KANSAS FRIDAY EVENING. THE UPPER LEVEL FLOW OVER THE CENTRAL PART OF THE COUNTRY BECOMES EVEN MORE MERIDIONAL THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THE MEDIUM RANGE MODELS HAVE ALL BEEN TRENDING IN THIS DIRECTION THROUGH THE PAST FEW RUNS. THINK THAT THE CURRENT WEEK TWO OUTLOOK SHOULD BE TRENDED BACK TO AT LEAST NEAR NORMAL TEMPERATURES FOR NOW BUT BASED ON FORECAST TEMPERATURES, WE COULD BE EVEN COOLER. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 625 PM CDT MON JUN 24 2013 SCATTERED THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP ALONG AND EAST OF A SURFACE BOUNDARY THAT EXTENDED FROM JUST WEST OF DODGE CITY INTO NORTH CENTRAL KANSAS EARLY THIS EVENING. BRIEF PERIODS OF WIND GUSTS UP TO 45 MPH, HAIL, AND HEAVY RAIN THAT WILL REDUCE VISIBILITIES TO LESS THAN ONE MILE WILL BRIEFLY BE POSSIBLE FROM A FEW OF THE STRONGER STORMS. AT THIS TIME WILL BASE TIMING OF THESE THUNDERSTORMS ON LATEST RADAR TRENDS AND HRRR WHICH INDICATES DODGE CITY AND HAYS WILL BE MAINLY IMPACTED FROM THESE STORMS. DODGE CITY UNTIL 0030 AND HAYS BETWEEN 02Z AND 04Z. AFTER THE STORMS PASS THE WINDS WILL SUBSIDE TO AROUND 15KNOTS AND VFR CONDITIONS ARE EXPECTED. && .PRELIMINARY POINT TEMPS/POPS... DDC 74 105 69 101 / 80 0 0 0 GCK 72 104 65 101 / 20 0 0 0 EHA 70 103 66 101 / 20 0 0 0 LBL 74 105 68 104 / 30 0 0 0 HYS 74 104 70 101 / 30 0 0 0 P28 74 100 74 101 / 20 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ030-031-043>046- 062>066-075>081-085>090. RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR KSZ061-062-074. && $$ SYNOPSIS...FINCH SHORT TERM...FINCH LONG TERM...GERARD AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS WICHITA KS
109 PM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 109 PM CDT SUN JUN 23 2013 ELEVATED SHOWER/THUNDERSTORM ACTIVITY CONTINUES TO WANE AS EXPECTED ALONG THE TURNPIKE CORRIDOR. OTHERWISE...ADDITIONAL SCATTERED THUNDERSTORMS ARE EXPECTED TO FORM LATE THIS AFTERNOON/EARLY EVENING ALONG A FRONT/OLD CONVECTIVE OUTFLOW DRAPED ACROSS CENTRAL/NORTHERN KS. DESPITE THE LAST SEVERAL RUNS OF THE HRRR...THERE REMAINS QUESTIONS REGARDING CONVECTIVE COVERAGE EARLY ON GIVEN CAP STRENGTH...ALTHOUGH PROBABILITIES SHOULD INCREASE BY MID-EVENING AS LOW-LEVEL JET INTENSIFIES. ML INSTABILITY UPWARDS OF 2500-3000 J/KG IN CONCERT WITH 25-40 KTS OF MID-LEVEL FLOW WILL LIKELY BE ENOUGH TO PRODUCE STRONG/SEVERE STORMS CAPABLE OF GOLFBALL SIZE HAIL AND DAMAGING DOWNBURST WINDS...WITH ACTIVITY POSSIBLY EVENTUALLY EVOLVING INTO A SEVERE MCS AS THE EVENING/OVERNIGHT PROGRESSES. ADK && UPDATE ISSUED AT 902 AM CDT SUN JUN 23 2013 PERSISTENT 315-320K ISENTROPIC ASCENT AMIDST A MOIST/UNSTABLE AIRMASS AS DEPICTED BY RUC SHOULD ALLOW ISOLATED TO WIDELY SCATTERED SHOWERS/THUNDERSTORMS TO LINGER THROUGH A GOOD PORTION OF THE MORNING OVER PORTIONS OF EAST-CENTRAL AND SOUTH-CENTRAL KS. ACTIVITY IS LIKELY ROOTED AT AND ABOVE 700MB...SO AVAILABLE INSTABILITY TO WORK WITH ISN`T FANTASTIC FOR HAIL PRODUCTION...BUT PROBABLY ENOUGH FOR SMALL HAIL IN THE STRONGEST CORES. AS ATMOSPHERE BECOMES BETTER MIXED WITH DAYTIME HEATING AND 800-600MB FLOW BACKS...ANTICIPATE THIS ACTIVITY TO GRADUALLY DISSIPATE BY AROUND LUNCHTIME. ADK && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 236 AM CDT SUN JUN 23 2013 LEE LOW WILL PERSIST NEAR THE CO/KS BORDER DURING THE PERIOD BENEATH SOUTHWESTERLY MID-LEVEL FLOW PATTERN. THIS WILL MAINTAIN STRONG A THERMAL RIDGE AND VERY WARM TEMPERATURES IN OUR AREA ALONG WITH GUSTY SOUTHERLY WINDS. A WEAK COLD FRONT POSSIBLY AIDED BY CONVECTIVE OUTFLOW FROM MCS IN NEBRASKA...WILL SINK INTO NORTHWESTERN KS THIS MORNING BEFORE STALLING. VERY STRONG INSTABILITY WILL DEVELOP THIS AFTERNOON IN OUR AREA AND NORTH OF THE FRONT WHERE LOW-LEVEL MOISTURE WILL BE POOLING. A FEW STORMS MAY TRY TO GET GOING IN THE WEAK FRONTAL CONVERGENCE ZONE LATE THIS PM ALTHOUGH CONVECTIVE INHIBITION MAY BE TOO STRONG TO OVERCOME. THE MORE PROBABLE SCENARIO IS THAT STORMS WILL FORM OVER THE HIGHER TERRAIN TO OUR WEST/NORTHWEST IN UPSLOPE FLOW IN THE PM/EVE...AND MOVE EASTWARD VIA CORFIDI PROPAGATION VECTORS SUNDAY NIGHT ACROSS NORTHERN KS/SOUTHERN NEB AS AN MCS CLUSTER OR TWO. THIS ACTIVITY WILL BE AIDED BY A WEAK SHORTWAVE OVER SOUTHERN CA EARLY THIS AM. THIS COULD AFFECT OUR CENTRAL KS COUNTIES ESP NEAR/NORTH OF I-70. STRONG-SEVERE WIND GUSTS COULD ACCOMPANY ANY STORMS THIS PM AND TONIGHT WITH DCAPES OF 1500-2000 J/KG. THE PROGGED FRONTAL SURFACE/OUTFLOW BOUNDARY SHOULD LIFT NORTH OF OUR AREA MONDAY WITH STRONG SOUTHERLY WINDS DEVELOPING IN CENTRAL/SOUTH CENTRAL KS. A WIND ADVISORY MAY BE REQUIRED. JMC .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 236 AM CDT SUN JUN 23 2013 THE MEDIUM RANGE MODELS REMAIN CONSISTENT IN DEPICTING AN AMPLIFYING UPPER PATTERN ACROSS THE CONUS...FEATURING A STRONG UPPER LEVEL HIGH DEVELOPING OVER THE SOUTHERN ROCKIES WITH UPPER TROUGHING DEEPENING OVER THE NORTHEAST. WEDNESDAY INTO THURSDAY WILL REMAIN HOT WITH HIGHS 100-103 IN CENTRAL/SOUTH CENTRAL KS...AND UPPER 90S SOUTHEAST. THE UPPER FLOW PATTERN WILL ALLOW A WEAK COLD FRONT TO PUSH SLOWLY SOUTHWARD THROUGH OUR AREA WITH SLIGHTLY COOLER/LESS HOT WEATHER BY FRIDAY/SATURDAY. VERY SLIGHT CHANCE OF THUNDERSTORMS AS THE FRONT MOVES THROUGH...TIED MAINLY TO WEAK FRONTAL CONVERGENCE AND STRONG DIURNAL HEATING. NOT OPTIMISTIC THAT MANY PLACES WILL GET RAIN HOWEVER. JMC && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 109 PM CDT SUN JUN 23 2013 STRONG/GUSTY SOUTHERLY WINDS WILL CONTINUE TO AFFECT THE REGION THROUGH THE NEXT 24 HOURS. OUTFLOW BOUNDARY/FRONT WILL BE FOCUS FOR SCATTERED THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EVENING FOR KSLN-KRSL...SOME OF WHICH COULD BE STRONG/SEVERE WITH LARGE HAIL AND DAMAGING WINDS. LATER TONIGHT WHEN ACTIVITY HAS WEAKENED...CANNOT COMPLETELY RULE OUT A FEW REMNANT SHOWERS/THUNDERSTORMS GETTING INTO KHUT-KICT. ADK && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 95 74 95 76 / 20 10 10 0 HUTCHINSON 97 74 97 76 / 10 20 10 10 NEWTON 94 74 95 75 / 20 10 10 0 ELDORADO 92 74 93 75 / 20 10 10 0 WINFIELD-KWLD 94 74 94 76 / 20 10 10 0 RUSSELL 98 70 99 75 / 30 40 10 10 GREAT BEND 98 71 99 75 / 20 30 10 10 SALINA 96 72 97 76 / 30 40 10 10 MCPHERSON 96 74 96 76 / 10 20 10 10 COFFEYVILLE 91 74 92 75 / 10 10 10 0 CHANUTE 91 74 91 75 / 10 10 10 0 IOLA 91 74 91 74 / 10 10 10 0 PARSONS-KPPF 90 74 91 75 / 10 10 10 0 && .ICT WATCHES/WARNINGS/ADVISORIES...NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
902 AM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 902 AM CDT SUN JUN 23 2013 PERSISTENT 315-320K ISENTROPIC ASCENT AMIDST A MOIST/UNSTABLE AIRMASS AS DEPICTED BY RUC SHOULD ALLOW ISOLATED TO WIDELY SCATTERED SHOWERS/THUNDERSTORMS TO LINGER THROUGH A GOOD PORTION OF THE MORNING OVER PORTIONS OF EAST-CENTRAL AND SOUTH-CENTRAL KS. ACTIVITY IS LIKELY ROOTED AT AND ABOVE 700MB...SO AVAILABLE INSTABILITY TO WORK WITH ISN`T FANTASTIC FOR HAIL PRODUCTION...BUT PROBABLY ENOUGH FOR SMALL HAIL IN THE STRONGEST CORES. AS ATMOSPHERE BECOMES BETTER MIXED WITH DAYTIME HEATING AND 800-600MB FLOW BACKS...ANTICIPATE THIS ACTIVITY TO GRADUALLY DISSIPATE BY AROUND LUNCHTIME. ADK && UPDATE ISSUED AT 720 AM CDT SUN JUN 23 2013 SCT -SHRA THAT DEVELOPED BETWEEN I-135 & I-35 ~600AM HAVE SLOWLY BUT GRADUALLY STRENGTHENED WITH ISOLD -TSRA BEGINNING TO APPEAR OVER NW BUTLER COUNTY AT 7AM. HAVE UPDATED ALL POP-RELATED GRIDS TO DEPICT THIS TREND. ALSO ADJUSTED POPS FOR THIS AFTERNOON TO BETTER ALIGN WITH ANTICIPATED COVERAGE & INTENSITY OF TSRA. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 236 AM CDT SUN JUN 23 2013 LEE LOW WILL PERSIST NEAR THE CO/KS BORDER DURING THE PERIOD BENEATH SOUTHWESTERLY MID-LEVEL FLOW PATTERN. THIS WILL MAINTAIN STRONG A THERMAL RIDGE AND VERY WARM TEMPERATURES IN OUR AREA ALONG WITH GUSTY SOUTHERLY WINDS. A WEAK COLD FRONT POSSIBLY AIDED BY CONVECTIVE OUTFLOW FROM MCS IN NEBRASKA...WILL SINK INTO NORTHWESTERN KS THIS MORNING BEFORE STALLING. VERY STRONG INSTABILITY WILL DEVELOP THIS AFTERNOON IN OUR AREA AND NORTH OF THE FRONT WHERE LOW-LEVEL MOISTURE WILL BE POOLING. A FEW STORMS MAY TRY TO GET GOING IN THE WEAK FRONTAL CONVERGENCE ZONE LATE THIS PM ALTHOUGH CONVECTIVE INHIBITION MAY BE TOO STRONG TO OVERCOME. THE MORE PROBABLE SCENARIO IS THAT STORMS WILL FORM OVER THE HIGHER TERRAIN TO OUR WEST/NORTHWEST IN UPSLOPE FLOW IN THE PM/EVE...AND MOVE EASTWARD VIA CORFIDI PROPAGATION VECTORS SUNDAY NIGHT ACROSS NORTHERN KS/SOUTHERN NEB AS AN MCS CLUSTER OR TWO. THIS ACTIVITY WILL BE AIDED BY A WEAK SHORTWAVE OVER SOUTHERN CA EARLY THIS AM. THIS COULD AFFECT OUR CENTRAL KS COUNTIES ESP NEAR/NORTH OF I-70. STRONG-SEVERE WIND GUSTS COULD ACCOMPANY ANY STORMS THIS PM AND TONIGHT WITH DCAPES OF 1500-2000 J/KG. THE PROGGED FRONTAL SURFACE/OUTFLOW BOUNDARY SHOULD LIFT NORTH OF OUR AREA MONDAY WITH STRONG SOUTHERLY WINDS DEVELOPING IN CENTRAL/SOUTH CENTRAL KS. A WIND ADVISORY MAY BE REQUIRED. JMC .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 236 AM CDT SUN JUN 23 2013 THE MEDIUM RANGE MODELS REMAIN CONSISTENT IN DEPICTING AN AMPLIFYING UPPER PATTERN ACROSS THE CONUS...FEATURING A STRONG UPPER LEVEL HIGH DEVELOPING OVER THE SOUTHERN ROCKIES WITH UPPER TROUGHING DEEPENING OVER THE NORTHEAST. WEDNESDAY INTO THURSDAY WILL REMAIN HOT WITH HIGHS 100-103 IN CENTRAL/SOUTH CENTRAL KS...AND UPPER 90S SOUTHEAST. THE UPPER FLOW PATTERN WILL ALLOW A WEAK COLD FRONT TO PUSH SLOWLY SOUTHWARD THROUGH OUR AREA WITH SLIGHTLY COOLER/LESS HOT WEATHER BY FRIDAY/SATURDAY. VERY SLIGHT CHANCE OF THUNDERSTORMS AS THE FRONT MOVES THROUGH...TIED MAINLY TO WEAK FRONTAL CONVERGENCE AND STRONG DIURNAL HEATING. NOT OPTIMISTIC THAT MANY PLACES WILL GET RAIN HOWEVER. JMC && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 720 AM CDT SUN JUN 23 2013 DRAWING IMMEDIATE ATTENTION IS SCT -TSRA THAT ARE SLOWLY STRENGTHENING BETWEEN I-135 & I-35 THIS MORNING. --RA OCCURRED AT KICT 625-640AM BUT HAVE MOVED NE OF THE TERMINAL. STILL CLOSE ENOUGH TO WARRANT A "VCTS" TIL 15Z. S WINDS TO INCREASE CONSIDERABLY OVER MOST AREAS LATE THIS MORNING (KRSL THE EXCEPTION) AS WEAK COLD FRONT STALLS IN NE-SW MANNER FROM ERN NEBRASKA TO SW KS. FRONT TO BECOME FOCUS FOR INCREASED TSRA LATE THIS AFTERNOON WITH COVERAGE SLOWLY SPREADING W/SW FROM NRN TO SW KS. HAVE KEPT "VCTS" INTACT FOR ALL AFFECTED TERMINALS BUT DETAILS WILL BE PROVIDED...ESPECIALLY FROM 24/00Z ISSUANCE ONWARD. && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 95 74 95 76 / 10 10 10 0 HUTCHINSON 97 74 97 76 / 10 20 10 10 NEWTON 94 74 95 75 / 20 10 10 0 ELDORADO 92 74 93 75 / 20 10 10 0 WINFIELD-KWLD 94 74 94 76 / 10 10 10 0 RUSSELL 98 70 99 75 / 20 40 10 10 GREAT BEND 98 71 99 75 / 10 30 10 10 SALINA 96 72 97 76 / 30 40 10 10 MCPHERSON 96 74 96 76 / 20 20 10 10 COFFEYVILLE 91 74 92 75 / 10 10 10 0 CHANUTE 91 74 91 75 / 10 10 10 0 IOLA 91 74 91 74 / 10 10 10 0 PARSONS-KPPF 90 74 91 75 / 10 10 10 0 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1146 PM CDT SAT JUN 22 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 306 PM CDT SAT JUN 22 2013 FORECAST HIGHLIGHTS FOCUS AROUND HOT AND WINDY WEATHER CONTINUING THROUGH MID WEEK...THUNDERSTORM CHANCES LATE SUN AFTERNOON-NIGHT OVER CENTRAL KS AND AGAIN THU-THU NIGHT AREAWIDE...AND A COOLING TREND BY LATE WEEK/NEXT WEEKEND. APPROACHING SHORTWAVE ENERGY SHOULD INITIATE A FEW THUNDERSTORMS OVER WESTERN KS LATE THIS AFTERNOON ALONG A SHARPENING DRYLINE. LAST 3 RUNS OF THE HRRR HAVE ALLUDED TO THIS. NOT OUT OF THE REALM OF POSSIBILITY THAT SOME OF THIS ACTIVITY COULD GET INTO RUSSELL AND BARTON COUNTIES BETWEEN 8 PM AND MIDNIGHT. HOWEVER...SUSPECT WEAK FORCING IN CONCERT WITH WARM MID-LEVEL TEMPERATURES/INCREASING CINH WILL LIKELY DISSIPATE THIS ACTIVITY BEFORE REACHING WESTERN CORRIDOR. ADDITIONAL ACTIVITY WILL LIKELY AFFECT NEBRASKA AND POSSIBLY FAR NORTHERN KS OVERNIGHT...BUT WILL LIKELY REMAIN NORTH OF THE FORECAST AREA. OTHERWISE...SHORTWAVE ENERGY PROGRESSING ACROSS THE NORTHERN PLAINS WILL ALLOW A COLD FRONT TO APPROACH CENTRAL KS SUNDAY. THE INCREASED CONVERGENCE AT PEAK HEATING COULD ALLOW A FEW ISOLATED STORMS TO FIRE ALONG THE FRONT SUNDAY LATE AFTERNOON...POSSIBLY AFFECTING LOCATIONS NORTH OF A GREAT BEND-SALINA LINE. HOWEVER...GIVEN WEAK FORCING AT PEAK HEATING...THINKING THE MORE PROBABLE SCENARIO IS CLUSTER OF THUNDERSTORMS DEVELOPING OVER NORTHWEST KS/SOUTHWEST NE AND PROPAGATING EAST/SOUTHEAST INTO CENTRAL KS AFTER DARK. GIVEN NAM`S PLACEMENT OF FRONT...THINKING LOCATIONS NORTH OF GREAT BEND-SALINA HAVE A DECENT CHANCE OF SEEING MOISTURE...ALONG WITH POTENTIAL FOR A STRONG/SEVERE FORWARD PROPAGATING MCS CARRYING AN ISOLATED DAMAGING WIND THREAT. FRONT LIFTS NORTH FOR MON-TUE...EFFECTIVELY SHUTTING DOWN PRECIPITATION CHANCES AND CONTINUING THE WINDY AND HOT WEATHER. WINDS WILL LIKELY FLIRT WITH WIND ADVISORY CRITERIA ONCE AGAIN SUN AND MON...AND POSSIBLY TUE AS WELL. FURTHERMORE...PER THE GFS...CANNOT COMPLETELY RULE OUT A STRAY THUNDERSTORMS GETTING INTO RUSSELL/BARTON COUNTIES TUE EVENING...BUT ONCE AGAIN SUSPECT BETTER CHANCES WILL REMAIN WEST/NORTHWEST. ADK .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 306 PM CDT SAT JUN 22 2013 THE UPPER RIDGE IS PROGGED TO BUILD IN EARNEST ACROSS THE WESTERN CONUS LATE NEXT WEEK. THE HIGHER AMPLITUDE FLOW REGIME WILL EVENTUALLY ALLOW A SIGNIFICANT UPPER TROF TO DROP SOUTHEAST ACROSS THE GREAT LAKES WHICH WILL DEVELOP INTO AN EASTERN CONUS LONGWAVE BY NEXT WEEKEND. THE RESULT FOR KANSAS WILL BE A CONTINUATION OF THE BREEZY AND HOT WEATHER THROUGH MID-WEEK WITH A COLD FRONTAL PASSAGE AND SOMEWHAT COOLER OR LESS HOT CONDITIONS BY FRIDAY/SATURDAY. LATEST PROGGED LOW LEVEL THICKNESS VALUES/THERMAL FIELDS WOULD SUPPORT HOTTER MAXS AHEAD OF THE FRONTAL PASSAGE FOR WEDNESDAY AND THURSDAY...WITH MAXS AT OR ABOVE THE CENTURY MARK FOR LOCATIONS ALONG/WEST OF I-135. THE GFS LATEST FRONTAL TIMING COULD ALLOW FOR A VERY HOT BUBBLE OF COMPRESSED AIR ON THE WESTERLY COMPONENT FLOW ACROSS MUCH OF SOUTHERN KANSAS ON THURSDAY AFTERNOON. SO FOR NOW HAVE MADE A SLIGHT UP-TWEAK TO THE LOADED INITIALIZATION WHICH IS ALSO ABOVE GMOS VALUES. WILL CONTINUE TO CARRY SLIGHT CHANCE POPS THURSDAY INTO EARLY FRIDAY...THOUGH FORCING REMAINS RATHER WEAK AND LIKELY TIED TO FRONTAL CONVERGENCE AND MAINLY DIURNALLY DRIVEN CONVECTION WITH CARRYOVER INTO THURSDAY NIGHT EARLY FRIDAY MORNING. DARMOFAL && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1142 PM CDT SAT JUN 22 2013 BREEZY SOUTHERLY WINDS WILL BEGIN TO DIMINISH ACROSS CENTRAL KANSAS ON SUNDAY AS A SURFACE TROUGH AXIS APPROACHES THE AREA. FURTHER EAST...ANOTHER BREEZY DAY IS ANTICIPATED WITH SPEEDS AROUND 25 KNOTS GUSTING INTO THE 30-35 KNOT RANGE. THIS TROUGH AXIS MAY ALSO SERVE AS A FOCUS FOR LATE AFTERNOON AND EVENING THUNDERSTORM DEVELOPMENT IMPACTING KRSL AND POSSIBLE KSLN DURING THE EVENING/OVERNIGHT HOURS ON SUNDAY. THERE IS STILL SOME CONCERN FOR AN ISOLATED SHOWER OR THUNDERSTORM IMPACTING CENTRAL KANSAS LATE TONIGHT/EARLY TOMORROW MORNING AS AN OUTFLOW BOUNDARY ACROSS WESTERN KANSAS RACES EASTWARD AFTER 12-14Z. && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 75 96 74 95 / 10 10 10 10 HUTCHINSON 75 98 74 97 / 10 10 20 10 NEWTON 74 96 74 95 / 10 10 10 10 ELDORADO 74 93 74 93 / 0 0 10 10 WINFIELD-KWLD 75 94 74 94 / 0 0 10 10 RUSSELL 75 99 70 98 / 10 20 40 10 GREAT BEND 75 100 71 98 / 10 10 30 10 SALINA 75 98 72 97 / 10 10 40 10 MCPHERSON 75 98 74 96 / 10 10 20 10 COFFEYVILLE 75 92 74 92 / 10 0 10 10 CHANUTE 74 92 74 91 / 10 0 10 10 IOLA 74 92 74 91 / 10 0 10 10 PARSONS-KPPF 75 92 74 91 / 10 0 10 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
220 AM EDT SUN JUN 23 2013 .UPDATE... ISSUED AT 1250 AM EDT SUN JUN 23 2013 UPDATED THE FORECAST TO REMOVE THE POPS AND FINE TUNE TEMPS THROUGH THE REST OF THE NIGHT. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS ALONG WITH A FRESHENED ZFP AND HWO. UPDATE ISSUED AT 1027 PM EDT SAT JUN 22 2013 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. ISOLATED THE SCATTERED THUNDERSTORMS HAVE BEEN PERCOLATING WEST OF A LINE FROM MOUNT STERLING TO HARLAN. A FEW OF THESE PULSING THUNDERSTORMS HAVE BECOME STRONG...HOWEVER THEY HAVE STAYED BELOW SEVERE CRITERIA. THE HRRR AND EXTRAPOLATION INDICATE ALL THE STORMS SHOULD BE MOVING OUT OF THE AREA BY MIDNIGHT. SOME AREAS DIRECTLY UNDERNEATH THE STORMS HAVE RECEIVED AND MUCH AS 1.5 INCHES OF RAIN...HOWEVER THE STORMS HAVE BEEN MOSTLY MISSING THE RAIN GAGES OUT THERE. WILL HAVE A BETTER IDEA WHEN ALL THE CO-OPS REPORT IN THE MORNING. THE REST OF FORECAST IS ON TRACK. UPDATE ISSUED AT 812 PM EDT SAT JUN 22 2013 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. THUNDERSTORMS HAVE BEEN HAVING A HARD TIME GETTING STRONG THIS AFTERNOON AND EVENING. PART OF THE PROBLEM IS SOME WARMING THE MID LEVELS WHICH IS HELPING TO CAP THEM OFF. THE STRONGEST STORMS THIS EVENING WERE OVER KNOX AND WAYNE COUNTIES. THEY NEVER QUITE GOT TO THE POINT WHERE A SPECIAL WEATHER STATEMENT WAS NEEDED AND THEY WERE NOT CLOSE TO THE CRITERIA WE USED TO ISSUE SEVERE THUNDERSTORM WARNINGS. EXPECT STORMS TO DIE OFF BY 10 PM. SOME PATCHY VALLEY FOG IS EXPECTED TONIGHT...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS EVENING. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM EDT SAT JUN 22 2013 CONVECTION ACROSS THE CWA HAS BEEN LIMITED SO FAR THIS AFTERNOON. APPEARS MID LEVEL CAPPING IS JUST A BIT TOO STRONG TO OVERCOME AND IS RESPONSIBLE FOR DAMPENING ACTIVITY THUS FAR. AS A RESULT PULLED BACK SLIGHTLY ON POPS FOR THE REMAINDER OF THE AFTERNOON. ALOFT A WEAK UPPER LOW WILL MOVE SLOWLY NORTHWARD ACROSS THE REGION DURING THE NEXT 24 HOURS. CAPPING SHOULD WEAKEN A BIT ON SUNDAY AS THE UPPER LOW MOVES OVERHEAD. SO CONTINUED TO ADVERTISE SLIGHTLY BETTER COVERAGE OR SCATTERED ACTIVITY SUNDAY AFTERNOON FOR AT LEAST A GOOD PORTION OF THE CWA. NO SIGNIFICANT CHANGES TO TEMPS. DID NUDGE THEM TOWARDS A BLEND OF LATEST MODEL GUIDANCE. WITH A PERSISTENT PATTERN IN PLACE THERE SHOULD NOT BE TOO MUCH VARIATION IN DAY TO DAY SENSIBLE WEATHER...A TYPICAL SUMMER LIKE PATTERN. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 PM EDT SAT JUN 22 2013 DURING THE FIRST HALF OF THE TIME FRAME THE MAIN WESTERLIES SHOULD BE TO OUR NORTH...WITH AN UPPER LEVEL RIDGE AXIS ORIENTED WEST/EAST OVER THE SOUTHERN CONUS. WITHOUT A CRUSHING RIDGE OVER US AND WITH A WARM AND MOIST AIR MASS STILL IN PLACE...WILL EXPECT SHOWERS AND THUNDERSTORMS TO POP UP AT TIMES. IT SHOULD BE LARGELY A DIURNAL TREND LINKED WITH PEAK HEATING. HOWEVER...DUE TO LACK OF FEATURES TO FOCUS CONVECTION...POPS WILL BE LOW...GENERALLY 20-30 PERCENT EACH AFTERNOON...AND DROPPING OFF AT NIGHT. LATE IN THE WEEK...THE UPPER RIDGE IS EXPECTED TO BUILD MUCH STRONGER OVER THE SOUTHWEST CONUS...ALLOWING TROUGHING TO DEVELOP IN THE EAST. SHORTWAVE TROUGHS DROPPING INTO THE SYNOPTIC SCALE TROUGH WILL THEN PROVIDE A FOCUS FOR CONVECTION. ONE SUCH SHORTWAVE TROUGH...ALBEIT FAIRLY WEAK...IS SHOWN BY BOTH THE ECMWF AND GFS MODELS ARRIVING ON THURSDAY. WILL USE LOW CHANCE POPS AREA WIDE WITH THIS. MODELS THEN SHOW THE LARGE SCALE UPPER TROUGH CONTINUING TO DEEPEN...AND BRINGING A SURFACE COLD FRONT INTO THE AREA FROM THE NORTHWEST ON FRIDAY. WILL RAISE POPS TO 50 PERCENT WITH THIS FEATURE. IF THE CURRENT FORECAST SCENARIO HOLDS IN FUTURE RUNS... POPS WILL LIKELY GO HIGHER. BOTH THE ECMWF AND GFS GENERATE PRECIP BEHIND THE COLD FRONT UNDER THE UPPER TROUGH ON SATURDAY. THE GFS DOES SHOW A SURFACE TROUGH MOVING THROUGH...AND GFS MEX MOS HAS 50 PERCENT POPS ON SATURDAY. HOWEVER...FORECAST SOUNDINGS DO NOT LOOK ALL THAT SUPPORTIVE OF PRECIP...AND THE ECMWF IS LIGHTER WITH ITS QPF FIELD THAN THE GFS. WILL UNDERCUT THE MOS AND GO WITH 30 PERCENT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 220 AM EDT SUN JUN 23 2013 ALTHOUGH VFR CONDITIONS CAN BE EXPECTED THROUGH THE BULK OF THE FORECAST PERIOD...THERE WILL LIKELY BE TIMES OF MVFR OR LOWER VIS AND CIGS EARLY THIS MORNING FROM FOG...ESPECIALLY AT LOZ WHERE A BIT OF RAIN AGAIN FELL. OTHERWISE...SCATTERED THUNDERSTORMS FROM MID DAY INTO THE EARLY EVENING ON SUNDAY WILL ALSO THREATEN TO REDUCE VIS AND CIGS TO MVFR...BUT MOST SITES WILL PROBABLY STAY STORM AND PROBLEM FREE. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...RAY LONG TERM...HAL AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1250 AM EDT SUN JUN 23 2013 .UPDATE... ISSUED AT 1250 AM EDT SUN JUN 23 2013 UPDATED THE FORECAST TO REMOVE THE POPS AND FINE TUNE TEMPS THROUGH THE REST OF THE NIGHT. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS ALONG WITH A FRESHENED ZFP AND HWO. UPDATE ISSUED AT 1027 PM EDT SAT JUN 22 2013 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. ISOLATED THE SCATTERED THUNDERSTORMS HAVE BEEN PERCOLATING WEST OF A LINE FROM MOUNT STERLING TO HARLAN. A FEW OF THESE PULSING THUNDERSTORMS HAVE BECOME STRONG...HOWEVER THEY HAVE STAYED BELOW SEVERE CRITERIA. THE HRRR AND EXTRAPOLATION INDICATE ALL THE STORMS SHOULD BE MOVING OUT OF THE AREA BY MIDNIGHT. SOME AREAS DIRECTLY UNDERNEATH THE STORMS HAVE RECEIVED AND MUCH AS 1.5 INCHES OF RAIN...HOWEVER THE STORMS HAVE BEEN MOSTLY MISSING THE RAIN GAGES OUT THERE. WILL HAVE A BETTER IDEA WHEN ALL THE CO-OPS REPORT IN THE MORNING. THE REST OF FORECAST IS ON TRACK. UPDATE ISSUED AT 812 PM EDT SAT JUN 22 2013 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. THUNDERSTORMS HAVE BEEN HAVING A HARD TIME GETTING STRONG THIS AFTERNOON AND EVENING. PART OF THE PROBLEM IS SOME WARMING THE MID LEVELS WHICH IS HELPING TO CAP THEM OFF. THE STRONGEST STORMS THIS EVENING WERE OVER KNOX AND WAYNE COUNTIES. THEY NEVER QUITE GOT TO THE POINT WHERE A SPECIAL WEATHER STATEMENT WAS NEEDED AND THEY WERE NOT CLOSE TO THE CRITERIA WE USED TO ISSUE SEVERE THUNDERSTORM WARNINGS. EXPECT STORMS TO DIE OFF BY 10 PM. SOME PATCHY VALLEY FOG IS EXPECTED TONIGHT...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS EVENING. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM EDT SAT JUN 22 2013 CONVECTION ACROSS THE CWA HAS BEEN LIMITED SO FAR THIS AFTERNOON. APPEARS MID LEVEL CAPPING IS JUST A BIT TOO STRONG TO OVERCOME AND IS RESPONSIBLE FOR DAMPENING ACTIVITY THUS FAR. AS A RESULT PULLED BACK SLIGHTLY ON POPS FOR THE REMAINDER OF THE AFTERNOON. ALOFT A WEAK UPPER LOW WILL MOVE SLOWLY NORTHWARD ACROSS THE REGION DURING THE NEXT 24 HOURS. CAPPING SHOULD WEAKEN A BIT ON SUNDAY AS THE UPPER LOW MOVES OVERHEAD. SO CONTINUED TO ADVERTISE SLIGHTLY BETTER COVERAGE OR SCATTERED ACTIVITY SUNDAY AFTERNOON FOR AT LEAST A GOOD PORTION OF THE CWA. NO SIGNIFICANT CHANGES TO TEMPS. DID NUDGE THEM TOWARDS A BLEND OF LATEST MODEL GUIDANCE. WITH A PERSISTENT PATTERN IN PLACE THERE SHOULD NOT BE TOO MUCH VARIATION IN DAY TO DAY SENSIBLE WEATHER...A TYPICAL SUMMER LIKE PATTERN. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 PM EDT SAT JUN 22 2013 DURING THE FIRST HALF OF THE TIME FRAME THE MAIN WESTERLIES SHOULD BE TO OUR NORTH...WITH AN UPPER LEVEL RIDGE AXIS ORIENTED WEST/EAST OVER THE SOUTHERN CONUS. WITHOUT A CRUSHING RIDGE OVER US AND WITH A WARM AND MOIST AIR MASS STILL IN PLACE...WILL EXPECT SHOWERS AND THUNDERSTORMS TO POP UP AT TIMES. IT SHOULD BE LARGELY A DIURNAL TREND LINKED WITH PEAK HEATING. HOWEVER...DUE TO LACK OF FEATURES TO FOCUS CONVECTION...POPS WILL BE LOW...GENERALLY 20-30 PERCENT EACH AFTERNOON...AND DROPPING OFF AT NIGHT. LATE IN THE WEEK...THE UPPER RIDGE IS EXPECTED TO BUILD MUCH STRONGER OVER THE SOUTHWEST CONUS...ALLOWING TROUGHING TO DEVELOP IN THE EAST. SHORTWAVE TROUGHS DROPPING INTO THE SYNOPTIC SCALE TROUGH WILL THEN PROVIDE A FOCUS FOR CONVECTION. ONE SUCH SHORTWAVE TROUGH...ALBEIT FAIRLY WEAK...IS SHOWN BY BOTH THE ECMWF AND GFS MODELS ARRIVING ON THURSDAY. WILL USE LOW CHANCE POPS AREA WIDE WITH THIS. MODELS THEN SHOW THE LARGE SCALE UPPER TROUGH CONTINUING TO DEEPEN...AND BRINGING A SURFACE COLD FRONT INTO THE AREA FROM THE NORTHWEST ON FRIDAY. WILL RAISE POPS TO 50 PERCENT WITH THIS FEATURE. IF THE CURRENT FORECAST SCENARIO HOLDS IN FUTURE RUNS... POPS WILL LIKELY GO HIGHER. BOTH THE ECMWF AND GFS GENERATE PRECIP BEHIND THE COLD FRONT UNDER THE UPPER TROUGH ON SATURDAY. THE GFS DOES SHOW A SURFACE TROUGH MOVING THROUGH...AND GFS MEX MOS HAS 50 PERCENT POPS ON SATURDAY. HOWEVER...FORECAST SOUNDINGS DO NOT LOOK ALL THAT SUPPORTIVE OF PRECIP...AND THE ECMWF IS LIGHTER WITH ITS QPF FIELD THAN THE GFS. WILL UNDERCUT THE MOS AND GO WITH 30 PERCENT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 812 PM EDT SAT JUN 22 2013 THUNDERSTORMS SHOULD DYE DOWN BY 2Z. EXPECT SOME PATCHY DENSE VALLEY FOG IN THE VALLEYS AGAIN TONIGHT...ESPECIALLY IN THE LOCATIONS THAT SAY RAINFALL TODAY. LOOKING FOR VFR CONDITIONS THROUGH THE BULK OF THE FORECAST. WILL ALL THINGS BEING PRETTY MUCH EQUAL DECIDED TO LEAN HEAVILY ON PERSISTENCE FOR TIMING OF LIGHT FOG AT EACH TERMINAL. LOOKING FOR DIURNAL ISOLD TO SCATTERED SHOWERS AND THUNDERSTORMS TO BEGIN FIRING ACROSS THE AREA AFTER 18Z. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...RAY LONG TERM...HAL AVIATION...JJ
AREA FORECAST DISCUSSION
NWS GRAY ME
342 PM EDT SUN JUN 23 2013 .SYNOPSIS... WARM AND MOIST AIR CONTINUES TO POOL SOUTH OF A STATIONARY FRONT TO OUR NORTH. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED EACH DAY THROUGH THE WEEK AS SEVERAL DISTURBANCES CROSS THE REGION. A LARGE UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST LATE IN THE WEEK. THIS WILL ALLOW FOR COOLER TEMPERATURES...BUT INCREASE THE CHANCE FOR SHOWERS ACROSS THE REGION. && .NEAR TERM /TONIGHT/... MESOSCALE MODELS LIKE THE HRRR HAVE A GOOD HANDLE ON ONGOING CONVECTION TO OUR WEST. SHOWERS AND THUNDERSTORMS WHICH HAVE FORMED IN THE HIGHER TERRAIN WILL COALESCE AND SPREAD DOWNSTREAM IN THE NEXT FEW HOURS AS A COLD POOL DEVELOPS. SHOWERS AND THUNDERSTORMS SHOULD FORM A LOOSE MULTICELL LINE OVER CENTRAL/SOUTHERN NEW HAMPSHIRE AND INTO SW MAINE...MOVING OFFSHORE THIS EVENING. THE SEVERE WEATHER THREAT LOOKS HIGHEST OVER SOUTHERN AND CENTRAL NEW HAMPSHIRE WHERE MORE INSOLATION HAS OCCURRED AND SURFACE-BASED CAPES OF 1200-1500 J/KG RESIDE. THE BIGGEST SEVERE WEATHER THREAT WILL BE DAMAGING WINDS. TRAINING...AMPLE UNIDIRECTIONAL SHEAR...AND PRECIPITATION LOADING WILL SUPPORT THE THREAT OF WET DOWNBURSTS. FACTORS LIMITING SEVERE WEATHER INCLUDE THE LACK OF ANY REAL FOCUSING MECHANISM OR UPPER LEVEL SUPPORT...AS WELL AS A RELATIVELY HIGH FREEZING LEVEL. NEW STORMS WILL LIKELY DEVELOP ALONG OUTFLOW MERGERS AND IN AREAS OF DIFFERENTIAL HEATING. GYX SOUNDING FROM THIS MORNING HAS 1.72 INCHES OF PRECIPITABLE WATER...WHICH IS CLOSE TO 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THE END OF JUNE. SATURATED AND WARM CLOUDS WILL CONTINUE TO SUPPORT VERY HEAVY RAIN AND WARM RAIN PROCESSES. QPF AMOUNTS FOR THIS EVENING WILL VARY WIDELY DEPENDING ON WHERE CONVECTION DEVELOPS. TRAINING CELLS AND ANY UPSLOPE COMPONENT WILL HELP TO LOCALLY BOOST RAINFALL TOTALS OVER ISOLATED AREAS...PERHAPS 1-2 INCHES. OTHER LOCATIONS MAY SEE LESS THAN A TENTH OF AN INCH. MUCH OF THE ACTIVITY WILL DIMINISH WITH THE LOSS OF DIURNAL HEATING...AND AS A WEAK SURFACE TROUGH SHIFTS OFFSHORE. OVERNIGHT LOWS WILL BE IN THE LOWER TO MID 60S AS THE LOWER LEVELS OF THE ATMOSPHERE REMAIN SATURATED...LEADING TO PATCHY DENSE FOG DEVELOPMENT. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... ANOTHER WEAK TROUGH CROSSES THE AREA TOMORROW WITH NEARLY ZONAL FLOW ALOFT. SKIES WILL BE PARTLY CLOUDY ACROSS THE SOUTH INITIALLY...AND THIS ALONG WITH WESTERLY WINDS WILL HELP BOOST TEMPERATURES INTO THE 80S AND 90S. DEW POINTS REMAIN IN THE UPPER 60S MAKING FOR AN UNPLEASANTLY MUGGY DAY. HEAT INDEX VALUES REACH THE LOWER 90S...STAYING SHORT OF ADVISORY CRITERIA. MOISTURE WILL BE WRUNG OUT ONCE AGAIN IN THE FORM OF AFTERNOON AND EVENING THUNDERSTORMS. HIGHER INSTABILITY WILL BE LOCATED OVER NORTHERN AREAS...BUT A THUNDERSTORM COULD POP UP ANYWHERE WITH BROAD WEAK FORCING. && .LONG TERM /TUESDAY THROUGH SUNDAY/... WARM AND HUMID WEATHER WILL CONTINUE THROUGH TUESDAY AND INTO WEDNESDAY. WARM 850 MB TEMPERATURES OF +18C COULD LEAD TO HIGHS REACHING THE 90 DEGREE MARK ACROSS SOUTHERN AND EASTERN NEW HAMPSHIRE AND SOUTHWEST MAINE. WITH DEW POINTS IN THE UPPER 60S TO LOW 70S... IT WILL BE HUMID. HEAT INDEX READINGS WILL TOP 90 DEGREES ACROSS THE COASTAL PLAIN OF MAINE AND NEW HAMPSHIRE... WITH SOME READINGS APPROACHING 95. ALTHOUGH THIS IS SHORT OF ADVISORY LEVELS... IT WILL STILL BE NOTICEABLY HOT AND HUMID. WITH HOT AND HUMID WEATHER COMES THE THREAT OF THUNDERSTORMS. A SHORTWAVE TROUGH WILL BE CROSSING SOUTHERN CANADA AND INTO NORTHERN NEW ENGLAND ON TUESDAY... ADDING UPPER LEVEL SUPPORT TO AN UNSTABLE AIR MASS TO PRODUCE THUNDERSTORMS ACROSS THE REGION. NAM IS SHOWING STRONGER MID AND UPPER LEVEL FLOW THAN THE GFS... AND IF THIS IS THE CASE THEN THERE WILL BE AMPLE DEEP LAYER SHEAR TO SUPPORT SUPERCELLS AND MULTICELL CLUSTERS AS DESCRIBED BY THE STORM PREDICTION CENTER IN THEIR MORNING OUTLOOK INDICATING A SLIGHT RISK ACROSS NORTHERN NEW ENGLAND. THE UNIDIRECTIONAL SHEAR INDICATES THAT THERE WILL BE PRIMARILY A DAMAGING WINDS AND HAIL THREAT RATHER THAN A TORNADO THREAT. IN ADDITION... THE HUMID AIR WILL ALLOW THUNDERSTORMS TO DROP VERY HEAVY RAINFALL. ANY TRAINING THUNDERSTORMS COULD LEAD TO FLASH FLOODING. WITH HIGH DEW POINTS EXPECTED... DO NOT EXPECT TEMPERATURES TO COOL OFF MUCH TUESDAY NIGHT. AFTER HIGHS IN THE 90S AND DEW POINTS IN THE UPPER 60S TO LOW 70S... IT WILL BE DIFFICULT FOR TEMPERATURES TO FALL MUCH BELOW 70 FOR MOST AREAS IN THE FEW HOURS OF NIGHT THAT EXIST THIS TIME OF YEAR. AS A RESULT... RAISED LOW TEMPERATURES FROM GUIDANCE VALUES AS MAV/MET TEND TO BE TOO COLD ON HUMID NIGHTS SUCH AS THIS. ANOTHER SHORTWAVE TROUGH CROSSES THE AREA TUESDAY NIGHT OR WEDNESDAY AND WILL PROVIDE ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS. TIMING DIFFERENCES IN THE MODELS MAKES IT DIFFICULT TO PROVIDE MORE CONFIDENCE VIA HIGHER POP VALUES. GFS AND CMC BOTH SEEM TO BE SUFFERING FROM FEEDBACK RESULTING FROM CONVECTION. GFS DEVELOPS A CLOSED 999 MB SURFACE LOW CROSSING THE AREA TUESDAY NIGHT WHILE THE CMC IS SIMILAR BUT NOT AS STRONG. THIS SOLUTION SEEMS UNLIKELY AND WAS DISCOUNTED IN FAVOR OF THE ECMWF WHICH SHOWS A MORE PROGRESSIVE SHORTWAVE CROSSING THE REGION. A COLD FRONT DROPS SOUTH ACROSS THE AREA ON WEDNESDAY... BRINGING COOLER AIR DOWN FROM THE GULF OF SAINT LAWRENCE AND EASTERN CANADA. 850 TEMPERATURES DROP ABOUT 4C WEDNESDAY AS COMPARED TO TUESDAY AND MAX TEMPERATURES SHOULD REFLECT THIS. HOWEVER... DOWNSLOPING NORTHWEST WINDS WILL PROVIDE FOR DEEP MIXING ALONG THE COASTAL PLAIN OF NEW HAMPSHIRE AND SOUTHWEST MAINE... ALLOWING TEMPERATURES TO CLIMB INTO THE MID TO UPPER 80S FOR ONE MORE DAY. HIGH PRESSURE BUILDING SOUTH OUT OF EASTERN CANADA WILL BRING AN EASTERLY TO SOUTHEASTERLY FLOW ON THURSDAY. ECMWF SHOWS A PRONOUNCED EASTERLY FLOW ACROSS THE AREA WHICH WOULD KEEP A COOL MARINE AIR MASS IN PLACE. WATER TEMPERATURES OFF THE NEW HAMPSHIRE COAST AREA IN THE LOW 60S... WHILE WATER TEMPERATURES OFF THE MIDCOAST OF MAINE ARE IN THE LOW 50S. EVEN THE GFS SHOWS A SOUTH TO SOUTHEAST FLOW ON THURSDAY WHICH WOULD KEEP MUCH OF MAINE COOL. AS A RESULT... HAVE GONE WITH COLDER TEMPERATURES FOR WEDNESDAY WITH HIGHS IN THE LOW 70S ACROSS MAINE TO THE UPPER 70S FOR NEW HAMPSHIRE. THIS WAS MORE IN LINE WITH THE ECMWF MOS AND HPC. ALL MODELS NOW IN GOOD AGREEMENT THAT A LARGE SCALE TROUGH WILL BE APPROACHING THE AREA BY THURSDAY NIGHT... SPREADING BROAD SCALE LIFT OVER NEW ENGLAND IN COMBINATION WITH AN ONSHORE SOUTHEAST FLOW. AS A RESULT... INCREASED POPS INTO THE 60 TO 70 PERCENT RANGE TO REFLECT THE INCREASED CONFIDENCE IN TIMING. UNFORTUNATELY... THIS BROAD SCALE TROUGH LINGERS TO THE WEST OF NEW ENGLAND THROUGH THE WEEKEND... LEAVING THE FORECAST AREA WITHIN THE FAVORABLE AREA FOR RISING MOTION AND PRECIPITATION. TIMING OF SUBTLE SHORTWAVE TROUGHS WITHIN THE FLOW AND ASSOCIATED SURFACE FEATURES VARIES AMONG THE MODELS AND IS DIFFICULT TO FORECAST THIS FAR OUT. AS A RESULT... HAVE INDICATED A CHANCE OF SHOWERS OR THUNDERSTORMS FROM FRIDAY THROUGH THE WEEKEND. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... SHORT TERM...VFR SKIES IN VCTS THIS EVENING. SHOWERS AND THUNDERSTORMS DIMINISH OVERNIGHT WITH PATCHY DENSE FOG AND STRATUS DEVELOPING. MOISTURE TRAPPED UNDER AN INVERSION WILL KEEP PERIODS OF LIFR AND VLIFR CEILINGS IN THE TERMINAL FORECASTS. WEST WINDS ON MONDAY MAY GUST INTO THE LOWER 20S. LONG TERM...OVERNIGHT FOG IS POSSIBLE EACH NIGHT IN THE VALLEY LOCATIONS... AS WELL AS AFTERNOON HAZE AND THUNDERSTORMS THROUGH TUESDAY. A COLD FRONT BRINGS COOLER AIR IN FOR WEDNESDAY. AN ONSHORE FLOW ON THURSDAY COULD BRING IFR CONDITIONS PERHAPS WORSENING TO LIFR BY THURSDAY NIGHT AND FRIDAY IN SHOWERS. && .MARINE... SHORT TERM...HELD OFF ON A SMALL CRAFT ADVISORY AS GUIDANCE HAS BEEN OVERDOING WAVE HEIGHTS. THAT SAID A FEW 5-6 FOOTERS MAY DEVELOP ON THE FAR OUTER WATERS. WINDS WILL STAY BELOW 25 KTS WITH A FEW GUSTS INTO THE LOWER 20S. LONG TERM...EXPECT A GENERAL SOUTHWEST FLOW OVER THE WATERS THROUGH WEDNESDAY THOUGH IT SHOULD REMAIN BELOW 25 KT. GFS MODEL IS FORECASTING A STRONGER SURFACE LOW TO CROSS INTO THE GULF OF MAINE FROM THE WEST ON WEDNESDAY BUT THIS IS LIKELY OVERDONE DUE TO CONVECTION WITHIN THE MODEL. AS A RESULT... WAVE HEIGHTS GENERATED BY THE WNA WAVE MODEL WERE TOO HIGH ON THE SOUTHWEST FLOW AHEAD OF THE FRONT. EXPECT WINDS AND WAVES TO STAY BELOW SMALL CRAFT ADVISORY CONDITIONS AHEAD OF AND BEHIND THE FRONT ON WEDNESDAY. HIGH PRESSURE DROPS SOUTH OUT OF CANADA AND INTO THE WESTERN ATLANTIC AND GULF OF MAINE FOR THURSDAY WITH A SOUTHERLY FLOW RETURNING BY FRIDAY. && .TIDES/COASTAL FLOODING... A PORTLAND HIGH TIDE OF 11.8 FT IS EXPECTED TONIGHT AT 11:41 PM. FLOOD STAGE AT PORTLAND IS 12.0 FT. WINDS WILL BECOME WSW TONIGHT AND NEARLY PARALLEL TO THE COAST. THIS IS NOT A FAVORED DIRECTION FOR COASTAL EROSION OR SPLASH OVER. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ HANES/KIMBLE
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
956 AM EDT SUN JUN 23 2013 .SYNOPSIS... WARM AND MOIST AIR CONTINUES TO POOL SOUTH OF A STATIONARY FRONT TO OUR NORTH. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED EACH DAY THROUGH THE WEEK AS SEVERAL DISTURBANCES CROSS THE REGION. A LARGE UPPER LEVEL TROUGH WILL APPROACH FROM THE WEST LATE IN THE WEEK. THIS WILL LOWER OUR TEMPERATURES...BUT INCREASE THE CHANCE FOR SHOWERS ACROSS THE REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... .UPDATE...THE LATEST GYX SOUNDING FROM THIS MORNING HAS 1.72 INCHES OF PRECIPITABLE WATER. THIS WILL SUPPORT VERY HEAVY RAIN AT TIMES AND HAVE INCREASED QPF FOR THIS AFTERNOON AND EVENING ACROSS MOST OF THE AREA. TRAINING AND ANY UPSLOPE COMPONENT WILL HELP BOOST RAINFALL TOTALS OVER ISOLATED AREAS. MESO MODELS LIKE THE HRRR HAVE A GOOD HANDLE ON CONVECTION THIS MORNING. THIS FIRST ROUND OF SHOWERS WILL REMAIN CONFINED TO THE COAST AND SOUTHERN NH. MODELS INITIATE CONVECTION AGAIN BY ROUGHLY 1 PM IN THE HIGHER TERRAIN BEFORE SPREADING THEM DOWNSTREAM. AN AREA OF HEAVIER SHOWERS AND THUNDERSTORMS SHOULD FORM A LOOSE MULTICELL LINE OVER SOUTHERN NH AND INTO SW MAINE LATE THIS AFTERNOON. BREAKS IN CLOUD COVER HAS ALLOWED MUCH OF NH TO RECEIVE INSOLATION. IF SEVERE WEATHER DOES DEVELOP...IT WOULD MOST LIKELY OCCUR OVER SOUTHERN AND CENTRAL NH. && PREVIOUS DISCUSSION...ATTM ONE S/WV IS SHEARING OUT TO THE E...WHILE A SECOND ENTERS THE WNW FLOW FROM THE UPPER MIDWEST CONVECTION TO OUR W. THE LEAD S/WV IS DRIVING SCT CONVECTION ACROSS THE NORTHEAST...PERCOLATING ON THE EDGE OF BUILDING HEAT DOME. THIS ACTIVITY WILL LIKELY CONTINUE INTO THE MORNING...AS TRAILING S/WV INDUCES SOME FASTER MID LVL FLOW FROM THE WSW. AS EVIDENT ON SATELLITE FOG PRODUCT ALREADY...SOME BREAKS IN THE CLOUDS ARE APPEARING ON THE SRN EDGE OF THESE SHRA/TSTMS. THIS WILL ALLOW STRONG INSOLATION TO TAKE PLACE EARLY IN THE DAY. TEMPS SHOULD QUICKLY RISE THRU THE 70S...REACHING THE UPPER 80S IN FAR SRN ZONES. CLOUDS AND ONSHORE COMPONENT TO THE WINDS FARTHER E WILL LIMIT OVERALL HIGH TEMPS. HOWEVER...INCREASINGLY MOIST AIR MASS WILL MAKE IT FEEL MUGGY ACROSS THE WHOLE AREA. QUESTION THEN BECOMES CONVECTIVE ACTIVITY THIS AFTERNOON. CRUDELY TAKING THE 23/00Z GYX SOUNDING AND MODIFYING FOR EXPECTED AFTERNOON TEMP AND DEW POINT FOR THE FOOTHILLS REGION...ABOUT 83/65...YIELDS ROUGHLY 1500 J/KG CAPE. WITH NO STRONG ADVECTIVE PROCESSES TAKING PLACE THIS SEEMS REASONABLE. SOME MODEL GUIDANCE IS AGGRESSIVELY JUICING THE LLVLS WITH UPPER 60S TO NEAR 70 DEW POINTS AND PRODUCING CAPE WELL OVER 2000 J/KG. NOT EXPECTED THIS KIND OF INSTABILITY TODAY...BUT RATHER 1000 TO 1500...WHICH IS MORE THAN ENOUGH FOR STRONGER STORMS. HOWEVER...WITH RIDGING IN PLACE AT H5 THERE LACKS A DISCERNIBLE TRIGGER TO SPARK TSTM DEVELOPMENT. MOST LIKELY WE/LL HAVE TO RELY ON STRONG DIURNAL HEATING. WILL HAVE TO MONITOR UPSTREAM S/WV TO SEE IF THIS SUBTLE FEATURE CAN ASSIST IN CONVECTIVE INITIATION. CONVECTION ALLOWING MODELS ARE IN REASONABLE AGREEMENT THAT DEVELOP OCCURS TODAY IN VICINITY OF THE NRN HUDSON AND CHAMPLAIN VALLEYS. THIS ACTIVITY SPILLS OVER INTO WRN ZONES BY MID AFTERNOON. FOR NOW HAVE KEPT POP IN THE SCT TO ISOLATED RANGE...GIVEN THE UNCERTAINTY IN THE FORECAST. PWATS PUSHING 2 SD ABOVE NORMAL POINT TOWARDS HEAVY RAINFALL BEING THE MAIN THREAT WITH AFTERNOON CONVECTION. GIVEN THE FORECAST WIND FIELD ALOFT...STORM MOTION SHOULD BE AOB 20 KT FROM THE WNW. SLOW STORM MOTION COULD YIELD SOME LOCALIZED FLOODING IF STORMS TRAIN OVER THE SAME AREAS. SHEAR AND INSTABILITY FAIL TO OVERLAP WELL THIS AFTERNOON...SO WIDESPREAD ORGANIZED STORMS APPEAR UNLIKELY. HOWEVER...MULTICELL CLUSTERS...STORM MERGERS...AND PRECIP LOADING IN THE COLUMN COULD LEAD TO A FEW GUSTY STORMS AND AN ISOLATED SEVERE WIND GUST. STRONG HEATING IN THE LOW LEVELS WILL BRING 0-3 KM LAPSE RATES UP TOWARDS 8 C/KM. THIS IS MORE THAN SUPPORTIVE OF GUSTY OUTFLOWS. FREEZING LVLS ARE HIGH...BUT SUFFICIENT CAPE EXISTS IN THE -10 TO -30 C LAYER TO GET SOME SUB SEVERE HAIL. CONVECTION WILL WANE QUICKLY AFTER SUNSET...AS LACK OF STRONG FORCING WILL LEAVE STORMS DEPENDENT ON DAYTIME HEATING. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... REMAINING SHRA/TSTMS WILL CONTINUE TO WEAKEN OVERNIGHT. A FEW SHRA COULD LINGER ON THE EDGE OF THE CAP IN THE FAR NRN ZONES AGAIN INTO THE MORNING. ANOTHER WARM AND MUGGY NIGHT IS EXPECTED...WITH PATCHY FOG...ESPECIALLY IN AREAS THAT RECEIVE RAINFALL THEN CLEAR OUT. ANOTHER HAZY...HOT...AND HUMID DAY WILL MEAN ANOTHER AFTERNOON WITH MODERATE INSTABILITY. DIURNAL SHRA/TSTMS WILL BE PSBL AGAIN DUE TO STRONG INSOLATION...BUT AGAIN THERE LACKS FORCING OTHERWISE. MORE NOTICEABLE MAY BE TEMPS RISING INTO THE 80S WITH DEW POINTS PUSHING 70. THIS WILL MEAN APPARENT TEMPS IN THE 90S...AND THE THREAT OF HEAT STRESS FOR ANYONE WITH ACTIVITIES OUTDOORS DURING MIDDAY. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... THE PATTERN WILL BE VERY SIMILAR OVER THE NEXT FEW DAYS FROM TOWN TO TOWN. A STRENGTHENING WESTERLY FLOW ALOFT WILL ALLOW INCREASINGLY WARMER AND MORE MUGGY AIR INTO THE REGION. ON MONDAY...EXPECT A FEW HIGH TEMPERATURES TO TOP OUT ABOVE 90 DEGREES OVER SOUTHERN NEW HAMPSHIRE AS 850 MB TEMPS REACH +18C. THERE WILL BE SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY DURING THE AFTERNOON AND EARLY EVENING HOURS AS A SHORT WAVE CROSSES THE REGION. THERE COULD BE A FEW STORMS ON MONDAY WITH DAMAGING WIND GUSTS AS CAPES AND PRECIPITABLE WATER VALUES REMAIN HIGH. SIMILAR CONDITIONS WILL CONTINUE ON TUESDAY...WITH MAINLY NOCTURNAL SHOWERS AND THUNDERSTORMS ACROSS THE REGION. MODELS VARY ON WHETHER A BACKDOOR COLD FRONT WILL CROSS THE REGION BY EARLY WEDNESDAY. IN ANY CASE...WINDS WILL VEER WITH TIME ON WEDNESDAY...ALLOWING SLIGHTLY COOLER AIR INTO THE REGION AFTER A WARM START. 00Z MODEL SUITE IN RELATIVELY CLOSE AGREEMENT BY THURSDAY AS LARGE TROUGH APPROACHES FROM THE WEST. THIS ALLOWS A SOUTHERLY SURFACE FLOW TO DEVELOP OFF THE CHILLY BRINK OF THE GULF OF MAINE AND THE ATLANTIC SEABOARD...DROPPING OUR TEMPS ACROSS THE REGION AND ALSO INCREASING OUR CHANCES OF RAINFALL FOR LATE IN THE WEEK. A WET...SHOWERY PATTERN WILL CONTINUE RIGHT INTO THE WEEKEND. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... SHORT TERM...PATCHY VALLEY FOG WILL PERSIST INTO THE MORNING...WITH OTHERWISE VFR HZ. SCT SHRA/TSTMS THIS AFTERNOON ARE EXPECTED FOR THE AREA...ESPECIALLY KHIE...KLEB...AND KCON. ANY SHRA/TSTM COULD BRING MVFR OR LOWER CONDS. SOME PATCHY FOG IS POSSIBLE AGAIN TONIGHT. SCT TO ISOLATED TSTMS ON MON COULD BRING MORE LOCAL MVFR OR LOWER CONDS. LONG TERM... EXPECT NOCTURNAL FOG TO BE THE ONLY MAJOR FLIGHT RESTRICTIONS OVER THE NEXT SEVERAL DAYS. SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH AFTERNOON...ESPECIALLY AT INLAND TERMINALS. && .MARINE... SHORT TERM...WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA THRESHOLDS FOR THE PERIOD. AN ISOLATED GUST NEAR 25 KT OR WAVE NEAR 5 FT IS POSSIBLE THIS AFTERNOON. LONG TERM... LIGHT SOUTHWEST FLOW EXPECTED AROUND HIGH PRESSURE TO THE EAST FOR MUCH OF THE WEEK. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ UPDATE...HANES LEGRO/JC
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1121 AM EDT SUN JUN 23 2013 .SYNOPSIS... PARTY CLOUDY SKIES AND WARM WEATHER WILL BE THE RULE THIS WEEK. THERE WILL BE A CHANCE OF SHOWERS OR A THUNDERSTORM ESPECIALLY IN AFTERNOON AND EARLY EVENING EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... 1115 UPDATE... CHALLENGING FORECAST FOR THIS AFTERNOON. CONVECTIVE CHANCES HAVE A LOT OF COMPETING PARAMETERS TODAY. BIG PLUME OF HIGHER PWATS OVER VA WILL PASS EAST OF THE AREA TODAY. STILL NOT A LOT OF DEEP LOW LEVEL MOISTURE IN AREA SOUNDINGS SUGGUESTING THAT INSTABILITY WILL PEAK BY EARLY AFTERNOON AND THEN DECREASE LATER TODAY AS THE BOUNDARY LAYER DEEPENS AND DRY AIR MIXES IN. OVERALL STILL THINK THAT SLIGHT CHANCE TO LOW CHANCE POPS ARE WARRANTED ESPECIALLY OVER TERRAIN. HRRR STILL SUGGESTING THAT WIDELY SCATTERED CONVECTION WILL DEVELOP ELSEWHERE. MINIMAL CHANGES TO THE FORECAST THIS MORNING. MANNING PREVIOUS... H5 RIDGE AXIS FINALLY PUSHING ACROSS FORECAST AREA TODAY AS WEAK UPPER LOW TN/KY SLIDES NORTHEAST. ALTHOUGH UPPER LOW WEAKENING...A LITTLE COLDER TEMPERATURES (-10 TO -12C) WILL TRANSLATE WITH LOW. DEW POINTS EXPECTED AT LEAST IN THE MID TO UPPER 60S. THE COMBINATION OF A LITTLE STEEPER MID-TROPOSPHERIC LAPSE RATES (MORE INSTABILITY) AND SIGNIFICANT LOW LEVEL MOISTURE WILL GIVE US A CHANCE OF AFTERNOON OR EVENING SHOWERS OR A THUNDERSTORM. WILL CARRY A 30 POP THIS AFTERNOON INTO THIS EVENING. AREA OF SIGNIFICANT PRECIPITABLE WATER (ALMOST 2 INCHES) LOCATED VIRGINIA PIEDMONT THIS MORNING. HOWEVER, NOT SURE THIS REALLY JUICY AIR WILL MAKE IT THIS FAR NORTH AND WEST. BEST MOISTURE FLUX AND MOISTURE TRANSPORT WOULD GIVE US A GLANCING BLOW AT BEST AND SUGGEST THAT BEST PW/S MIGHT PUSH OFF TO OUR EAST AS REMNANT LOW MOVES NORTH EAST. HOWEVER...WITH RELATIVELY SLOW MOVEMENT OF ANY CONVECTION AND RESPECTABLE MOISTURE COULD STILL GET SIGNIFICANT DOWNPOUR IN ANY CONVECTION. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... RATHER FLAT UPPER H5 FLOW INTO MONDAY...HOWEVER WEAK IMPULSE IN UPPER FLOW AND DIURNAL HEATING ADDING INSTABILITY...SO WILL CONTINUE WITH CHANCE POPS OF SHOWERS AND THUNDERSTORM...ESPECIALLY LATE AFTERNOON AND EVENING. ON TUESDAY...A LITTLE STRONG UPPER LEVEL SHORT WAVE PUSHES EAST IN A GENERAL ZONAL H5 FLOW. THE ADDED MID-TROPOSPHERIC LIFT COMBINED WITH ADDED INSTABILITY AND A TAD BIT MORE SHEAR SHOULD GIVE US A LITTLE BETTER CHANCE OF SHOWERS AND THUNDERSTORMS AND WENT WITH NEAR 50 POP FOR AFTERNOON AND EVENING. NAM A LITTLE FASTER WITH THIS IMPULSE THAN GFS...BUT BOTH MODELS EXHIBIT A BROADER PRECIP FIELD WITH APPROACH OF THIS UPPER SHORT WAVE. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... THE MODELS CONTINUE TO SUPPORT A SHIFT FROM A ZONAL PATTERN TO A MORE AMPLIFIED ONE AS A RIDGE BUILDS OVER THE WESTERN CONUS THROUGH THE WEEK. HOWEVER...EACH MODEL CONTINUES TO HANDLE THE SERIES OF FAST MOVING SHORTWAVES EMBEDDED WITHIN THE FLOW DIFFERENTLY. WITH LOWER CONFIDENCE...KEPT POPS MOSTLY IN THE CHANCE CATEGORY FOR MUCH OF THE FORECAST PERIOD UNTIL BOTH THE GFS...ECMWF...AND THE ENSEMBLE MEANS SWING A COLD FRONT ACROSS THE REGION OVER THE WEEKEND. DESPITE THE BLANKET CHANCE POPS...THINK THAT MUCH OF THE CONVECTION WILL REMAIN DIURNALLY DRIVEN THROUGH THE PERIOD. IN ADDITION...ALL GUIDANCE CONTINUES TO SUGGEST TEMPERATURES WILL BE ABOVE SEASONAL AVERAGES UNTIL THE COLD FRONT PASSAGE. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... GENERAL VFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE TAF PERIOD AS HIGH PRESSURE SHIFTS OFF EAST AND A CUTOFF UPPER LOW SLOWLY WOBBLES NORTHWARD TOWARD THE REGION. WHILE THIS LOW COULD LEAD TO A BETTER FOCUS FOR CONVECTION...MOST OF THE GUIDANCE STILL SUGGESTS COVERAGE WILL BE WIDELY SCATTERED. THUS...WILL LEAVE THE THUNDER MENTION OUT OF ANY TAF SITES FOR NOW. DIURNAL CUMULUS IS EXPECTED AFTER SUNRISE. SOUTHWESTERLY WINDS OF 5-10KTS ARE EXPECTED THROUGH THE AFTERNOON. OUTLOOK.../SUNDAY THROUGH THURSDAY/... GENERALLY VFR BUT WITH INCREASING CHANCES FOR SOME EARLY MORNING FOG AS HUMIDITY INCREASES. SCATTERED SHOWERS AND THUNDERSTORMS WILL RETURN TO THE FORECAST FOR SUNDAY AFTERNOON THROUGH AT LEAST MIDWEEK. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
422 PM EDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 418 PM EDT SUN JUN 23 2013 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER SE SASK INTO SRN MANITOBA WITH A SHORTWAVE TROUGH EXTENDING INTO ERN ND AND NW MN. AT THE SFC...A 999MB SFC LOW WAS LOCATED OVER THE NW CORNER OF MN WITH A WARM FRONT EXTENDING INTO SRN LAKE SUPERIOR. CLEARING AND AFTERNOON HEATING HAS PUSHED TEMPS INTO THE LOWER 80S OVER WRN UPPER MI RESULTING IN MLCAPE VALUES TO AROUND 1500 J/KG. SCT SHRA/TSRA WERE DEVELOPING OVER WRN LAKE SUPERIOR INTO NW UPPER MI CLOSEST TO THE FORCING ASSOCIATED WITH THE ND/MN SHRTWV. EXPECT THAT SCT SHRA/SHRA WILL CONTINUE TO DEVELOP BACK THROUGH WRN UPPER MI LATE THIS AFTERNOON AS A WEAK TROUGH MOVES INTO THE AREA...PER HIGH RES MODELS. INSTABILITY ALONG WITH 30-35 KT 0-6KM SHEAR AND 20-25 KT 0-1KM SHEAR COULD SUPPORT AT LEAST ISOLD STRONG/SEVERE STORMS...WITH STRONG WIND GUSTS AS THE MAIN HAZARD GIVEN DCAPE VALUES INTO THE 500-1000 J/KG RANGE. EXPECT THAT THE SHRA/TSRA WILL SPREAD INTO CNTRL UPPER MI BY 21Z-23Z AND THEN DISSIPATE AND WEAKEN BY LATE EVENING AS THE SHRA/TSRA MOVE TOWARD THE ERN CWA...AWAY FROM THE THE STRONGER INSTABILITY AND THE SHRTWV FORCING. AS THE SHORTWAVE AND LOW MOVE INTO NRN ONTARIO THE DRY SLOT AND STRONG MID LEVEL DRYING WILL SPREAD ACROSS THE REGION LATE TONIGHT INTO MONDAY. THIS WILL HELP MINIMIZE CHANCES FOR ADDITIONAL CONVECTION. WITH SUNSHINE AND 850 MB TEMPS STILL AROUND 15C...TEMPS WILL AGAIN CLIMB INTO THE LOWER 80S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 418 PM EDT SUN JUN 23 2013 GENERAL AGREEMENT IN OVERALL LOOK OF LARGER SCALE PATTERN INTO NEXT WEEKEND THOUGH DETAILS AND SPECIFICS REMAIN UNCERTAIN. TO START ON MONDAY EVENING...FAIRLY STRONG SHORTWAVE TROUGH WILL BE HEADING EAST ACROSS NORTHERN ONTARIO LEAVING RIDGING IN ITS WAKE OVER NORTHERN PLAINS. SFC FRONT AND POOL OF SFC-H85 MOISTURE ALONG THE BOUNDARY DRIVES SOUTH OF CWA BY LATE MONDAY EVENING RESULTING IN GENERALLY QUIET AND LESS HUMID WEATHER INTO MUCH OF TUESDAY. GFS AND ECMWF AGREE HERE...WHILE THE GEM-NH AND THE UKMET DO NOT PUSH WARM FRONT FAR ENOUGH SOUTH TO KEEP CHANCES OF SHRA/TSRA OUT OF CWA. WILL LEAN ON THE MORE CONSISTENT ECMWF IDEA WHICH IS SUPPORTED BY WPC HAND DRAWN SFC MAP. WITH WARM FRONT AND EDGE OF SFC BASED-MUCAPE MOST LIKELY STILL SOUTH BY TUESDAY AFTN...WONDER IF MOST AREAS STAY DRY THROUGH TUESDAY. ANY SHRA/TSRA THAT FORM MONDAY NIGHT INTO TUESDAY MORNING SHOULD STAY SOUTH OF CWA PER H85-H3 THICKNESSES AND FORWARD PROPAGATING CORFIDI VECTORS AND EVEN THE MEAN LAYER WIND. INTO TUESDAY NIGHT...ECMWF AND GFS STILL HAVE SHORTWAVE CRASHING THROUGH TOP EDGE OF LARGER SCALE RIDGING. WAVE MAY AID IN BRINGING AT LEAST H85 FRONT FAR ENOUGH NORTH THAT SOUTHERN TIER COULD BE AFFECTED BY SHRA/TSRA TUESDAY NIGHT AND MUCH OF THE CWA COULD SEE SHRA/TSRA ON WEDNESDAY. GFS STRONGER WITH THIS WAVE SO MUCH THAT IT PUSHES SFC WARM FRONT INTO CWA ON WEDNESDAY. PV ANAMOLY THAT GFS CARRIES IN HERE ON WEDNESDAY TRACKS BACK TO SOUTH EDGE OF STRONG UPR LOW OVER THE ALLUTIANS THIS MORNING. WAVE LOOKS PRETTY VIGOROUS ON WV LOOP. ECMWF HAS BETTER TRACK RECORD IN THE EXTENDED...BUT WILL BLEND SOME OF THE GFS IDEA IN AS WELL SINCE IT SEEMS TO HAVE SOME MERIT. TROUGH AND HIGHER SFC-H85 DWPNTS PUSH THROUGH AREA WEDNESDAY EVENING AND COOLER AIR ARRIVES LATER ON THURSDAY. GFS QUICKER AND STRONGER AS WELL AS FARTHER SOUTH WITH SHORTWAVE TROUGH DIGGING ACROSS UPR LAKES ON THURSDAY WHILE THE ECMWF SHOWS MORE SEPARATION BTWN THE WAVE ON WEDNESDAY AND THAT STRONGER TROUGHING. GFS HAS TENDENCY TO BRING SYSTEMS IN TOO QUICKLY AND ITS SOLUTION VERIFYING AT 12Z THURSDAY HAS SHOWN TOO MUCH INCONSISTENCY TO PUT MUCH STOCK IN IT AT THIS POINT. ECMWF HAS TRENDED A BIT SHAPRER WITH TROUGH BUT OVERALL HAS BEEN MUCH MORE CONSISTENT THAN GFS. WILL PREFER THAT IDEA FOR NOW. RESULT WILL BE SCT SHRA/TSRA...MAYBE EVEN NMRS FOR A TIME WEDNESDAY OR WEDNESDAY EVENING...THEN DIMINISHING WITH LOSS OF INSTABILITY AXIS LATER WEDNESDAY NIGHT. POTENTIAL FOR ANOTHER ROUND OF SCT SHRA/TSRA DURING PEAK HEATING ON THURSDAY AS AIRMASS OVER THE REGION IS STILL A BIT UNSTABLE /MLCAPES UP TO 1000 J/KG/ WHILE WNW FLOW ALOFT INCREASES ON SOUTH EDGE OF UPPER TROUGH. LIGHT AND VARIABLE SFC WINDS COULD RESULT IN LAKE BREEZE CONVERGENCE AS WELL. ALWAYS HAVE TO WATCH OUT FOR WNW-NW FLOW ALOFT AS THAT PATTERN WITH SUFFICIENT INSTABILITY IS ONE THAT CAN RESULT IN AT LEAST SOME CHANCE OF SEVERE WEATHER. UPPER TROUGH DOMINATES ON FRIDAY WITH A BIT COOLER AND UNSETTLED WEATHER. NO TSRA EXPECTED ON FRIDAY AS COOLER TEMPS ALOFT/STEEPER LAPSE RATES SETUP FROM NORTHERN ONTARIO INTO THE LOWER GREAT LAKES. COULD BE SHRA AT TIMES THOUGH AS SMALLER SCALE SHORTWAVES ROTATE AROUND PRIMARY UPPER TROUGH. FRIDAY NIGHT INTO SATURDAY MAY BE KIND OF BLUSTERY ALONG LK SUPERIOR AND WITH ONSHORE WINDS SWIM RISK MAY BE HIGHER TO START THE WEEKEND. SMALL CHANCES OF SHRA MAY LINGER INTO SATURDAY AS WELL. TEMPS SOME AREAS FRIDAY INTO SATURDAY MAY END UP MORE THAN 10 DEGREES BELOW NORMAL. HIGH PRESSURE BUILDS IN FOR LATER IN THE WEEKEND...RESULTING IN TEMPS BOUNCING UP AT LEAST TOWARD NORMAL. NEXT SHORTWAVE IN WNW FLOW APPEARS LATE IN THE WEEKEND SO HAVE POPS MOVING BACK IN FOR LATE SUNDAY. NO REAL WARM TEMPERATURES SEEN NEXT WEEKEND OR EVEN INTO EARLY NEXT WEEK AS TROUGHING ALOFT OVER EASTERN CANADA AND GREAT LAKES KEEPS WARM AIR RESTRICTED TO WESTERN AND SOUTHERN PORTIONS OF CONUS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 157 PM EDT SUN JUN 23 2013 VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE AFTERNOON. HOWEVER...SCT SHRA/TSRA ARE EXPECTED TO DEVELOP AND MOVE THROUGH CMX/SAW WHICH WOULD BRING A PERIOD OF MVFR CONDITIONS WITH THE POTENTIAL FOR GUSTY WINDS. HOWEVER...THERE WAS STILL SOME UNCERTAINTY WITH THE TIMING/COVERAGE OF ANY TSRA. AFTER A TROUGH MOVES THROUGH THIS EVENING...SLIGHTLY DRIER AIR WILL MOVE IN KEEPING MAINLY VFR CONDITIONS INTO MONDAY MORNING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 418 PM EDT SUN JUN 23 2013 WINDS SHOULD REMAIN 25 KTS OR LESS THROUGH THE UPCOMING WEEK. MAIN HAZARD WILL BE SCT THUNDERSTORMS TONIGHT AND FOG. DENSE FOG ADVISORIES HAVE BEEN EXTENDED THROUGH TONIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL 5 AM EDT /4 AM CDT/ MONDAY FOR LSZ162- 263>267. LAKE MICHIGAN... DENSE FOG ADVISORY UNTIL 8 AM EDT MONDAY FOR LMZ248-250. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
119 AM EDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 423 PM EDT SAT JUN 22 2013 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM ALBERTA INTO THE NRN ROCKIES AND A RIDGE OVER THE CNTRL GREAT LAKES RESULTING IN SW FLOW FROM THE PLAINS THROUGH THE UPPER MS VALLEY. THE MOST PROMINENT UPSTREAM SHORTWAVE TROUGH WAS MOVING THROUGH WRN WYOMING. WIDESPREAD LOW LEVEL MOISTURE AND CLOUDS PREVAILED NORTH OF A WARM FRONT EXTENDING FROM SE MN THROUGH CNTRL WI. TO THE SOUTH OF THE FRONT...TEMPS OVER ERN IA HAD CLIMBED INTO THE MID AND UPPER 80S WITH DEWPOINTS INTO THE LOWER 70S. TONIGHT...AS THE MID LEVEL RIDGE BUILDS TO THE EAST...THE SW FLOW PATTERN WILL ALLOW THE SFC-850 MB WARM FRONT TO PUSH TO THE NORTH. ALTHOUGH CONVECTION IS EXPECTED TO REDEVELOP ALONG OR AHEAD OF THE WARM FRONT THIS EVENING.....UNCERTAINTY WITH THE TIMING/POSITION OF ANY UPSTREAM SHRTWVS AND THE EVOLUTION OF CONVECTION IS HIGH. WITH THE FOCUS FOR MOISTURE/LOW LEVEL THETA-E ADVECTION SHIFTING FROM THE UPPER MS VALLEY TOWARD THE CWA...POPS INCREASE INTO THE WRN CWA AND ACROSS UPPER MICHIGAN BUT ARE STILL LIMITED TO CHANCE CATEGORY. SINCE MUCAPE VALUES ARE ONLY EXPECTED IN THE 400-800 J/KG RANGE...ONLY ISOLD TSRA WERE MENTIONED. POTENTIAL FOR STRONG OR SEVERE STORMS SHOULD REMAIN FARTHER SOUTH NEAR THE GREATER INSTABILITY. SUNDAY...AS THE WY SHRTWV LIFTS INTO THE NRN PLAINS A STRENGTHENING SFC LOW OVER THE ERN DAKOTAS WILL BRING INCREASING SRLY FLOW INTO THE WRN LAKES AND SHOULD FINALLY PUSH THE WARM FRONT NORTH OF UPPER MI. HOWEVER...CINH WILL ALSO INCREASE WITH 700 MB TEMPS INTO THE 10C-12C RANGE. SO...TEMPS WILL CLIMB WELL ABOVE NORMAL INTO THE MID/UPPER 80S AND CONVECTION POTENTIAL WILL BE LIMITED OVER THE CNTRL AND EAST. HOWEVER...SHRA/TSRA WILL INCREASE AGAIN BY MIDDAY SUN INTO SUN AFTERNOON AS MODELS CONTINUE TO SUGGEST A WEAK SHRTWV/IMPULSE COULD BRUSH MAINLY THE WRN CWA. MLCAPE VALUES INTO THE 1500-2000 J/KG RANGE COMBINED WITH 0-6KM SHEAR VALUES IN THE 30-40 KT RANGE COULD SUPPORT SOME STRONGER AND POSSIBLY SEVERE STORMS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 423 PM EDT SAT JUN 22 2013 UPPER AIR PATTERN SUNDAY NIGHT INDICATES A DEEPER TROUGH LIFTING INTO SCNTRL CANADA WITH RIDGING CENTERED OVER OHIO VALLEY. SFC WARM FRONT SHOULD BE VCNTY OF UPR MICHIGAN/LK SUPERIOR. H85 FRONT ALSO SHOULD BE MAINLY NORTH OF CWA. FORECAST WILL ASSUME THAT IS GOING TO BE THE CASE AS LAST COUPLE DAYS...SFC WARM FRONT HAS REMAINED FARTHER SOUTH THAN FORECAST THANKS TO TSRA AND ASSOCIATED RAIN COOLED OUTFLOW. DO THINK FRONT WILL HAVE BETTER SHOT OF MAKING IT NORTH OF UPR MICHIGAN BY SUNDAY NIGHT DUE TO SW FLOW AHEAD OF STRONGER SHORTWAVE ALOFT. BASED ON INITIAL FOCUS REGION FOR SHRA/TSRA AND H7 WINDS/FORWARD PROPAGATING CORFIDI VECTORS AND 850-300MB THICKNESS...EXPECT CHANCES OF SHRA/TSRA SUNDAY NIGHT TO MAINLY BE OVER WESTERN THIRD OF UPR MICHIGAN AND ACROSS LK SUPERIOR ON EDGE OF H7 CAPPING TIED TO ELEVATED MIXED LAYER /EML/. AS MENTIONED IN SHORT TERM DISCUSSION...BASED ON AVAILABLE INSTABILITY AND DEEP LAYER SHEAR...THERE WILL BE POTENTIAL FOR STRONG OR SEVERE STORMS SUNDAY EVENING OVER THE WEST. NAM/ECMWF FITS THIS EXPECTATION THE BEST WHILE THE GEM-NH AND GFS SEEM TO SHOW QPF TOO FAR EAST INTO THE CAPPED AREA. THOSE IDEAS WOULD HAVE BETTER CHANCE OF VERIFYING IF THE SFC-H85 FRONTS END UP FARTHER SOUTH THAN FORECAST. CHANCES FOR SHRA/TSRA ON MONDAY LIKELY HIGHEST DURING THE MORNING AND HIGHEST OVER THE EASTERN CWA ON EDGE OF CAPPING THAT WILL BE BEING SHUNTED TO THE EAST AND SOUTH AT THAT TIME AS H85 WINDS VEER MORE WESTERLY. WILD CARD FOR MONDAY IS IF TAIL OF SHORTWAVE AND ASSOCIATED HEIGHT FALLS MOVING ACROSS NORTHERN LK SUPERIOR ARE SUFFICIENT ENOUGH TO TRIGGER OTHER SHRA/TSRA ON EDGE OF CAPPING AND MUCAPE GRADIENT JUST UPSTREAM AND/OR JUST SOUTH OF UPR MICHIGAN. A PRETTY LOW CHANCE OF THIS...BUT IF IT WOULD HAPPEN THEN THERE IS POSSIBILITY OF SHRA/TSRA COMPLEX IMPACTING PARTS OF CWA ON MONDAY MORNING. INTO MONDAY AFTN...WIND FIELD BECOMES GENERALLY LIGHT AND VARIABLE WHICH OPENS DOOR FOR LK BREEZE SHRA/TSRA OVER MAINLY CNTRL UPR MICHIGAN /MQT-ESC-P53/. KEPT A SMALL POP IN THERE. WOULD BE VERY LOW CHANCE IF THERE IS MORE FORMIDABLE CONVECTION AROUND MONDAY MORNING AS SUBSIDENCE LATER IN THE DAY WOULD LIKELY PUT CAP ON ANY ADDITIONAL SHRA/TSRA. HIGHS ON MONDAY COULD SURGE INTO THE LOW-MID 80S OVER SCNTRL BUT SHOULD STAY IN THE MID-UPR 70S ELSEWHERE. WILL BECOME INCREASINGLY LESS HUMID LATER MONDAY AFTN OVER WESTERN UPR MICHIGAN. DEVELOPING ONSHORE FLOW IN AFTN MAY RESULT IN SOME FOG IN IMMEDIATE LK SUPERIOR SHORELINE AREAS EAST OF MQT. GOING TO GO FOR PERIOD OF QUIET WEATHER MONDAY NIGHT AND FOR MOST OF TUESDAY AS WELL. SFC-H85 FRONTAL BOUNDARIES AND ASSOCIATED SHRA/TSRA LOOK TO SETTLE WELL TO SOUTH OF CWA MONDAY EVENING. OTHER THAN WEAKER SHORTWAVES TRAVELLING THROUGH GENERAL FLAT RIDGING ALOFT...THERE REALLY IS NOT A STRONG ENOUGH FEATURE TO BRING THE FRONTS BACK TO THE NORTH. EXPECT SHRA/TSRA TO STAY OVER SOUTHERN HALF OF MN AND WI MONDAY NIGHT INTO TUESDAY MORNING. PERHAPS ISOLD SHRA/TSRA MAKE INTO TO THE WI BORDER LATE TUESDAY AFTN/EVENING AS SFC-H85 FRONTS TRY TO LIFT BACK TO THE NORTH OUT AHEAD OF LARGER SCALE TROUGHING MOVING ACROSS SCNTRL CANADA. ON THE OTHER HAND...MAYBE THIS NEXT ROUND OF SHRA/TSRA REMAINS MAINLY TO THE SOUTH OF UPR MICHIGAN SINCE SFC FRONT/MORE ABUNDANT INSTABILITY STAYS TO THE SOUTH. TOUGH TO SAY REALLY AS AT THE SAME TIME...H7 TEMPS PROGGED TO SURGE UPWARD AS CAPPING BUILDS JUST TO THE SOUTH OF UPR MICHIGAN. KEPT POPS CHANCE ALL AREAS...WITH HIGHEST CHANCES CONFINED TO SOUTH CENTRAL UPR MICHIGAN. KEPT SIMILAR IDEA GOING WEDNESDAY AS WELL WITH HIGHEST POPS ALONG WI BORDER INTO SCNTRL UPR MICHIGAN. WENT WITH MORE BROADBRUSHED APPROACH TO POPS WEDNESDAY NIGHT INTO THURSDAY AS COLD FRONT PRESSES IN FROM MANITOBA/ONTARIO AHEAD OF DEEPER UPR LEVEL TROUGH THAT DIGS INTO UPR LAKES REGION THURSDAY NIGHT INTO FRIDAY. WARM AND HUMID AIRMASS EXITS TO THE EAST BY THURSDAY NIGHT. HIGH TEMPS FOR FRIDAY AND NEXT SATURDAY SHOULD END UP BLO NORMAL ALL AREAS. COULD SEE CHANCES OF MAINLY RAIN SHOWERS /NO TSRA/ AS UPR TROUGH SETTLES ACROSS THE AREA. GUSTY NORTHWEST WINDS LIKELY AS WELL ALONG LK SUPERIOR ON FRIDAY AS THE COOLER AIR ARRIVES. PATTERN WILL FAVOR POTENTIAL FOR INCREASED SWIM RISK ON THE LAKE SUPERIOR BEACHES FOR FRIDAY. ARRIVAL OF THE COOLER AND DRIER AIRMASS SHOULD FINALLY SCOUR OUT THE FOG ON LK SUPERIOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 118 AM EDT SUN JUN 23 2013 WITH ABUNDANT LOW-LEVEL MOISTURE LINGERING OVER THE REGION TO THE N OF A WARM FRONT...IFR/LIFR CONDITIONS ARE EXPECTED THRU THE NIGHT AT KCMX/KSAW AS BOTH OF THESE TERMINALS WILL ALSO HAVE A LIGHT UPSLOPE WIND. UNDER A DOWNSLOPE SE/S WIND AT KIWD...CONDITIONS THERE SHOULD NOT FALL BLO MVFR. DAYTIME HEATING COMBINED WITH WARM FRONT LIFTING N OF THE AREA TODAY WILL RESULT IN ALL TERMINALS IMPROVING TO VFR. AS FOR PCPN...SHRA/TSRA POTENTIAL REMAINS UNCERTAIN. THERE APPEARS TO BE INCREASING POTENTIAL FOR SHRA/TSRA IN THE MORNING HRS AS WARM FRONT LIFTS N INTO THE AREA. HAVE INCLUDED VCSH TO TREND TOWARD PCPN POSSIBILITY. NOT THE IDEAL TIME OF DAY FOR TSRA...BUT TSRA NOT OUT OF THE QUESTION. MAY SEE ANOTHER ROUND OF SHRA/TSRA LATE THIS AFTN/EVENING AS INSTABILITY BUILDS IN WARM/HUMID AIR MASS. HOWEVER...CONFIDENCE IN COVERAGE/LOCATION OF ANY CONVECTION THAT MIGHT DEVELOP IS VERY LOW. FOR NOW...ONLY INCLUDED VCTS LATE AFTN AT KSAW AS SOME OF THE HIGHER RESOLUTION MODEL GUIDANCE HINTS AT A BETTER POTENTIAL OF CONVECTION ACROSS CNTRL UPPER MI. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 423 PM EDT SAT JUN 22 2013 WINDS SHOULD REMAIN 25 KTS OR LESS THROUGH THE UPCOMING WEEK. MAIN HAZARDS FOR MOST OF THE TIME WILL CONTINUE TO BE THUNDERSTORMS AND FOG. DENSE FOG ADVISORIES HAVE BEEN EXTENDED INTO SUNDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL 10 AM EDT /9 AM CDT/ THIS MORNING FOR LSZ162-240>250-263>267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...ROLFSON MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
133 AM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 645 PM CDT SAT JUN 22 2013 RECENT TRENDS WITH THE HRRR ALONG WITH HEAVY RAIN PROBABILITIES FROM THE SREF AND THE OVERNIGHT QPF PLACEMENT FROM THE ECMWF HAS PROMPTED A FLASH FLOOD WATCH THROUGH EARLY SUNDAY MORNING FOR A GOOD PORTION OF CENTRAL AND SOUTHERN MN. RAINFALL AMOUNTS FROM THE HRRR ARE IN THE 2 TO 3 INCH RANGE FROM MONTEVIDEO AND APPLETON ON EAST THROUGH THE TWIN CITIES. THIS LINES UP WELL WITH THE SREF PROBABILITIES OF 1 AND 2 INCH RAINS OVERNIGHT AND THE 12 HOUR QPF FROM THE ECMWF. THIS IS ALSO AT THE NOSE OF THE RAP 925-850MB MOISTURE TRANSPORT BETWEEN 06Z AND 12Z. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 334 PM CDT SAT JUN 22 2013 BIG THING TO START OFF THE SHORT TERM IS THE PRESENCE OF A STRENGTHENING WARM FRONT ACROSS SRN MN...WHICH STRETCHES FROM MARSHALL OVER TO FARIBAULT AND LA CROSSE AT 330 PM. SOUTH OF THE BOUNDARY...SKIES HAVE CLEARED...WITH TEMPS RISING TO AROUND 90 TO GO WITH MID/UPPER 60 DEWPOINTS. THIS BOUNDARY IS BEING REINFORCED BY A COOL AND SHALLOW RIDGE OF HIGH PRESSURE THAT HAS COME DOWN FROM THE NORTHEAST OFF OF LAKE SUPERIOR. FARTHER WEST...THERE IS A DIFFUSE PRESSURE TROUGH/FRONT ORIENTED N/S ACROSS THE CENTRAL DAKOTAS. TONIGHT...THE WARM FRONT WILL TRY TO PUSH NORTH TO ABOUT THE I-94 CORRIDOR...BUT WILL CONTINUALLY BE STRUGGLING AGAINST LAKE SUPERIOR HIGH. BY SUNDAY MORNING...THE TROUGH BACK OVER THE DAKOTAS WILL MOVE INTO MN AND WILL BE BISECTING MN FROM THE SW CORNER UP TOWARD THE INL AREA BY SUNDAY AFTERNOON. FOR TONIGHT...LOTS OF UNCERTAINTY WITH HOW CONVECTION WILL EVOLVE. ATMOSPHERE OVER MN/NRN WI REMAINS OVERTURNED AND WORKED OVER FROM LAST NIGHTS CONVECTION...AS EVIDENCED BY MID LEVEL LAPSE RATES ON THE SPC MESO ANALYSIS OF 5 TO 7 DEG C PER KM....THOUGH THEY HAVE STARTED TO SHOWS SIGNS OF RECOVERING IN THE LAST COUPLE OF HOURS. THESE WEAK LAPSE RATES WILL LIKELY KEEP THINGS FAIRLY BENIGN ACROSS THE MPX AREA UNTIL CLOSER TO 00Z. AS 00Z APPROACHES...A 30-40KT LLJ WILL BEGIN COMING UP OUT OF IA AND IMPINGING ON THE WARM FRONT ACROSS MN...WHICH SHOULD REALLY START TO RAMP UP PRECIP CHANCES. MAIN QUESTION THEN FOR TONIGHT BECOMES HOW FAR NORTH DOES THE WARM FRONT AND NOSE OF THE LLJ GO. ONCE AGAIN...EXPECT THE NOSE OF THE LLJ TO BE VERY ACTIVE...WITH WIDESPREAD TSRA THAT WILL HAVE THE POTENTIAL TO TRAIN...WITH ANOTHER ROUND OF HEAVY RAIN AND FLASH FLOODING BEING POSSIBLE TONIGHT. IN ADDITION TO THE HEAVY RAIN...SHEAR WILL BE SUFFICIENT ENOUGH TO WARRANT A RISK OF SEVERE WEATHER THROUGH THE NIGHT...WITH THE MAIN TREAT BEING WET MICRO/DOWN BURSTS ONCE AGAIN. GOING WITH A BLEND OF THE ECMWF/GFS/NAM...THE PART OF THE AREA THAT WOULD BE MOST AT RISK FOR SEEING THUNDERSTORMS WOULD ESSENTIALLY BE THE HEART OF THE MPX CWA FROM SW MN...UP THROUGH THE TWIN CITIES AND OVER INTO WRN WI. UNFORTUNATELY...HI-RES MODELS ARE OF NO USE TONIGHT...AS EACH WRF MEMBER HAS ITS OWN UNIQUE IDEA OF HOW THINGS WILL EVOLVE. AND THE HRRR HAS SHOWN CONSIDERABLE VARIABILITY FROM RUN TO RUN. GIVEN ALL OF THE UNCERTAINTY...CAN NOT PIN DOWN EXACTLY WHERE THE GREATEST FLASH FLOOD EXISTS THROUGH TONIGHT...SO HAVE OPTED NOT TO ISSUE A FLASH FLOOD WATCH. GREATEST THREAT OF COURSE WOULD BE ALONG/NORTH OF THE WARM FRONT...WHEREVER IT DECIDES TO SETUP SHOP TONIGHT. FOR SUNDAY...THE DAKOTAS BOUNDARY WILL BE DRIFTING INTO MN...WITH DRIER AIR COMING IN BEHIND IT. THIS MAY ACTUALLY ALLOW FOR A DRY DAY IN WRN MN...BUT ON THE OTHER SIDE OF THE CWA...THE LLJ WILL BE INCREASING BY THE AFTERNOON...WITH THUNDERSTORMS EXPECTED TO AGAIN EXPAND IN COVERAGE FROM SOUTH CENTRAL MN INTO WRN WI. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 334 PM CDT SAT JUN 22 2013 THUNDERSTORM ACTIVITY WILL LIKELY BE ONGOING AT THE START OF THE LONG TERM PERIOD SUNDAY EVENING ACROSS WRN WI. WEST OF THE COLD FRONT...DRIER AIR WILL FINALLY BRING CLEARING CONDITIONS AND A RESPITE FROM REPEATED ROUNDS OF CONVECTION SUNDAY NIGHT AND MONDAY. RIDGING WILL BUILD OVER THE PLAINS MONDAY. 925 MB TEMPS MONDAY WILL RISE TO BETWEEN +23 AND +25C...SO THINKING HIGHS IN THE UPPER 80S ARE LIKELY AND SEVERAL LOCATIONS OVER SWRN MN COULD REACH THE LOWER 90S. THE NOSE OF MID LEVEL RIDGING WILL BEGIN TO REACH SRN MN TUESDAY. MODELS CONTINUE TO ADVERTISE ANOTHER DISTURBANCE SLIDING AROUND... AND TO THE NORTH OF THIS RIDGING MONDAY NIGHT AND TUESDAY. MAINTAINED MEDIUM POPS THROUGHOUT THIS TIME. FOLLOWING THE PASSAGE OF THE ANY MORNING MCS/S...TUESDAY MAY TURN HOT AND HUMID PRIOR TO COLD FRONTAL PASSAGE TUESDAY EVENING. NAM WOULD FAVOR HIGHS IN THE LOW/MID 90S WITH PRONOUNCED THERMAL RIDGING. GFS/ECMWF ARE SLIGHTLY COOLER ACROSS THE ERN CWA WITH MCS CLOUDINESS PERSISTING INTO THE AFTERNOON HOURS. A MUCH DRIER PERIOD WILL TAKE HOLD IN THE LATTER HALF OF THE LONG TERM WITH RIDGING RETROGRADING BACK INTO THE WESTERN STATES AND A ZONAL TO NORTHWEST FLOW RETURNING TO THE MIDWEST/GREAT LAKES. THIS WILL BRING COOLER THAN NORMAL TEMPERATURES TO MUCH OF THE EASTERN CONUS HEADING INTO THE HOLIDAY WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1242 AM CDT SUN JUN 23 2013 NOCTURNAL CONVECTION AGAIN FIRING OVER SRN MN...N OF A LINGERING STNRY FNT OVER NR IA. THIS FNT WILL TRANSITION TO A WMFNT AND SLOWLY LIFT N OVERNIGHT AS ADDITIONAL STORMS TRAVERSE THE FNT FROM W TO E. KRWF THE FIRST TO BE AFFECTED...THEN ACTIVITY WILL STEADILY SPREAD E. CONDS WILL LIKELY DEGRADE TO MVFR AND POSSIBLY IFR IN THE TSTM ACTIVITY. THAT BEING SAID...HAVE ALSO SEEN REPORTS OF A FEW POCKETS OF IFR CIGS...BUT THESE ARE NOT EXPECTED TO LAST LONG...ESP IF RAIN WASHES IT OUT. CONDS TO GENERALLY IMPROVE TO VFR BY LATE MRNG AS MIXING OCCURS WITH INCRG S WINDS. VFR WILL THEN PERSIST THRU MOST OF THE DAY FOR WRN-CENTRAL MN WHILE WRN MN INTO WRN WI SEE OCNL MVFR CONDS WITH LINGERING SHWRS. KMSP...MAIN CONCERN REMAINS THE TIMING OF TSTMS. BEST TIMING PUTS TSTMS INTO THE MSP AREA 07Z-10Z BUT COULD LAST SLIGHTLY LONGER. MVFR-IFR CIGS WILL LINGER IN THE WAKE OF THESE STORMS. CONDS IMPROVE GRADUALLY THRU THE DAY WHILE SHWRS/TSTMS DEVELOP E OF THE MSP TERMINAL. AFTER RELATIVELY LIGHT E WINDS THIS MRNG...SE WINDS INCRS TO ARND 15 KT THRU THIS AFTN WITH OCNL GUSTS TO ARND 25MPH. /OUTLOOK FOR KMSP/ MON...VFR. WIND SE 5-10 KTS. MON NIGHT...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SE 5-10 KTS. TUE...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SSE 10-15 KTS. WED...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S SHIFT TO NW 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...FLASH FLOOD WATCH UNTIL 10 AM CDT THIS MORNING FOR MNZ041-042- 047>049-051-054>062-064>069-073>076-082-083-091. WI...NONE. && $$ UPDATE...RAH SHORT TERM...MPG LONG TERM...BORGHOFF AVIATION...JPC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1054 PM CDT Mon Jun 24 2013 .UPDATE... Issued at 1052 PM CDT MON JUN 24 2013 Neither the short range convection allowing models nor 00z NAM have much of a clue to the ongoing convection from southwest KS through west central MO. Activity appears to be aligning itself wsw-ene along a weak area of frontogenesis within the h8-h7 layer best depicted by the 02z RAP. The southerly h8 winds of 40-45kts is advecting ample moisture/instability across this boundary and with CIN values increasing since sunset this now supports elevated vs surface based convection. While the initial activity into our western counties tends to weaken/dissipate believe convection further upstream over KS will stand a better chance of surviving as it spreads eastward overnight and thus chance PoPs are warranted for the far west central and northwest portions of the CWA. && .SHORT TERM...(This Evening through Tuesday Night) Issued at 355 PM CDT MON JUN 24 2013 Main concern will be with potential for convection again tonight and then increasing heat conditions Tuesday. Latest HRRR model shows shortwave trough in synoptic flow to hold together as it moves into eastern Kansas. Dynamics are fairly weak as this is just a ripple in the nearly zonal flow over the region. However...there is some modest instability and potential for a decent LLJ late tonight....so another nocturnal MCS could move through...especially in northern zones where mid level lapse rates favor better instability. On Tuesday...there still is a chance in the afternoon in the northern zones for some convection to fire as yet another very weak short wave trough moves through. Also of concern is what might be left over in terms of outflow boundaries from any activity tonight. Therefore...will keep a chance in the northern zones for tomorrow. Meanwhile the thermal ridge begins to build to the west with 850mb temperatures into the middle and upper 20s deg C in western and central Kansas. As this thermal ridge moves towards the area...we will see heat indices begin to edge up to low 100s. Will not issue advisory for Tuesday but have mentioned it in the hazardous weather outlook. Tuesday night...yet another chance for some nocturnal MCS activity mainly in the northeastern zones as the thermal ridge axis moves over the western areas and should limit convection there. .LONG TERM...(Wednesday through Monday) Issued at 355 PM CDT MON JUN 24 2013 Beginning in the middle of the work week, the flattened zonal flow across the nation will begin to amplify as the prevailing westerlies begin to buckle across the U.S.A./Canadian border. The buckling in the flow will be lead by a weak shortwave Wednesday, with our region quickly finding itself in the the northwest flow as the ridge axis of the amplifying ridge pops up to to our west. However, as the weekend arrives the trough across the Great Lakes will gather some energy, expanding enough to possibly but much of our forecast area on the cool side of the still prevailing northwest flow. The pattern for the week will dictate hot and humid conditions through the middle of the work week, with Wednesday and Thursday being particularly muggy and troublesome. Dew points will be critical mid-week on determining the need for a heat advisory as heat indices will be ranging in the low 100s. Currently, forecast numbers are coming up just shy of criteria, though this currently looks due to the fact that afternoon dew points will likely mix out a little as the hot air advecting in aloft from the southwest will also be a bit dry. By Friday...temperatures are expected to back off a little from the hot and humid readings of the previous few days as the trough over the Great Lakes begins to dominate the eastern CONUS. Readings for Friday will still reach in the 90s, but the humidity wont be as bad; and for the weekend temperatures should range through the 80s. As for precipitation, only true potential for more than isolated storms looks to be focused on Thursday night into Friday morning as the edge of the Great Lakes trough begins pushing back to the southwest. Have kept PoPs in the chance category owing to the vagaries of forecast timing in a northwest flow. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening) Issued at 640 PM CDT MON JUN 24 2013 Over the next hour a small area of showers may just nick the KMKC terminal at the start of the forecast. Otherwise, rain chances tonight likely hinge on evolution of convection currently developing over southwest KS. Will lean more towards the latest HRRR model output as not overly impressed by the other short range convection allowing models. HRRR suggests the activity over KS will fall apart as it tracks east but could last long enough for a few cells to reach all 3 terminals after midnight. Low confidence of storms survival favors using VCTS. Bulk of forecast will see broken alto-cumulus with cigs above 12k ft agl with gusty southerly winds dying off by sunset but reforming by mid Tuesday morning. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...MJ SHORT TERM...Adolphson/73 LONG TERM...Cutter AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
643 PM CDT Mon Jun 24 2013 .SHORT TERM...(This Evening through Tuesday Night) Issued at 355 PM CDT MON JUN 24 2013 Main concern will be with potential for convection again tonight and then increasing heat conditions Tuesday. Latest HRRR model shows shortwave trough in synoptic flow to hold together as it moves into eastern Kansas. Dynamics are fairly weak as this is just a ripple in the nearly zonal flow over the region. However...there is some modest instability and potential for a decent LLJ late tonight....so another nocturnal MCS could move through...especially in northern zones where mid level lapse rates favor better instability. On Tuesday...there still is a chance in the afternoon in the northern zones for some convection to fire as yet another very weak short wave trough moves through. Also of concern is what might be left over in terms of outflow boundaries from any activity tonight. Therefore...will keep a chance in the northern zones for tomorrow. Meanwhile the thermal ridge begins to build to the west with 850mb temperatures into the middle and upper 20s deg C in western and central Kansas. As this thermal ridge moves towards the area...we will see heat indices begin to edge up to low 100s. Will not issue advisory for Tuesday but have mentioned it in the hazardous weather outlook. Tuesday night...yet another chance for some nocturnal MCS activity mainly in the northeastern zones as the thermal ridge axis moves over the western areas and should limit convection there. .LONG TERM...(Wednesday through Monday) Issued at 355 PM CDT MON JUN 24 2013 Beginning in the middle of the work week, the flattened zonal flow across the nation will begin to amplify as the prevailing westerlies begin to buckle across the U.S.A./Canadian border. The buckling in the flow will be lead by a weak shortwave Wednesday, with our region quickly finding itself in the the northwest flow as the ridge axis of the amplifying ridge pops up to to our west. However, as the weekend arrives the trough across the Great Lakes will gather some energy, expanding enough to possibly but much of our forecast area on the cool side of the still prevailing northwest flow. The pattern for the week will dictate hot and humid conditions through the middle of the work week, with Wednesday and Thursday being particularly muggy and troublesome. Dew points will be critical mid-week on determining the need for a heat advisory as heat indices will be ranging in the low 100s. Currently, forecast numbers are coming up just shy of criteria, though this currently looks due to the fact that afternoon dew points will likely mix out a little as the hot air advecting in aloft from the southwest will also be a bit dry. By Friday...temperatures are expected to back off a little from the hot and humid readings of the previous few days as the trough over the Great Lakes begins to dominate the eastern CONUS. Readings for Friday will still reach in the 90s, but the humidity wont be as bad; and for the weekend temperatures should range through the 80s. As for precipitation, only true potential for more than isolated storms looks to be focused on Thursday night into Friday morning as the edge of the Great Lakes trough begins pushing back to the southwest. Have kept PoPs in the chance category owing to the vagaries of forecast timing in a northwest flow. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening) Issued at 640 PM CDT MON JUN 24 2013 Over the next hour a small area of showers may just nick the KMKC terminal at the start of the forecast. Otherwise, rain chances tonight likely hinge on evolution of convection currently developing over southwest KS. Will lean more towards the latest HRRR model output as not overly impressed by the other short range convection allowing models. HRRR suggests the activity over KS will fall apart as it tracks east but could last long enough for a few cells to reach all 3 terminals after midnight. Low confidence of storms survival favors using VCTS. Bulk of forecast will see broken alto-cumulus with cigs above 12k ft agl with gusty southerly winds dying off by sunset but reforming by mid Tuesday morning. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...Adolphson/73 LONG TERM...Cutter AVIATION...MJ
AREA FORECAST DISCUSSION
NWS BILLINGS MT
915 AM MDT SUN JUN 23 2013 .UPDATE... ZONAL FLOW HAS SET UP ACROSS THE AREA TODAY IN THE WAKE OF YESTERDAYS SHORT WAVE TROUGH. SURFACE LOW OVER NORTHERN NORTH DAKOTA IS WRAPPING PRECIPITATION BACK INTO NORTHEAST MONTANA THIS MORNING BUT RAIN WILL STAY NORTH OF FALLON COUNTY. HAVE REMOVED POPS THERE FOR THIS MORNING. WESTERLY FLOW WILL BRING DRIER AIR INTO THE FORECAST TODAY AND TEMPERATURES WILL WARM INTO THE MID TO UPPER 70S AT MOST LOCATIONS. 12Z TEMPERATURE GUIDANCE AGREES WELL WITH CURRENT FORECAST HIGHS AND NO CHANGES MADE. ONLY OTHER CHANGE WAS TO LOWER CLOUD COVER OVER OUR NORTHEAST ZONES THIS MORNING. RICHMOND && .SHORT TERM...VALID FOR TDY AND MON... A WARMING TREND IS IN STORE TODAY AND MON IN THE WAKE OF THE SHORT WAVE TROUGH WHICH BROUGHT MOISTURE SAT. OUR ATTENTION WILL TURN TO A CONDITIONAL RISK OF SEVERE STORMS IN SOUTHEASTERN MT BY MON AS A PLUME OF HIGHER BOUNDARY LAYER MOISTURE TRIES TO MAKE A RUN TOWARD AT LEAST BAKER JUST AS 500-HPA FLOW BECOMES SOUTHWEST ONCE MORE. TODAY...A DRYING AND WELL-MIXED AIR MASS WILL YIELD A WARM DAY. WE HAVE HIGHS A BIT ABOVE THE 00 UTC MULTI-MODEL CONSENSUS OVER PARTS OF THE AREA IN RESPECT TO EXPECTED MIXING...WHICH SHOULD EXTEND TO 600 HPA IN SOUTH CENTRAL MT AND 700 HPA IN SOUTHEASTERN MT. ONLY A LOW POP WAS RETAINED IN BAKER THIS MORNING. WE ALSO WENT WITHOUT A MENTION OF FOG...AS VISIBILITIES OVER SOUTHEASTERN MT HAVE COME UP SINCE 06 UTC AS WINDS BECAME WEST-SOUTHWEST. HRRR OUTPUT ALSO SAYS MOST OF THE FOG WILL STAY NORTH AND EAST OF THE AREA THIS MORNING. TONIGHT...A QUIET PERIOD IS IN STORE FOR MOST OF THE AREA...BUT WE WILL NEED TO CONSIDER THE POTENTIAL FOR ELEVATED CONVECTION ACROSS SOUTHEASTERN MT WITH LATER FORECASTS. SERIOUS THOUGHT WAS GIVEN TO ADDING SOME LOW POPS FOR STORMS AFTER 09 UTC TO AT LEAST BAKER AND EKALAKA AS A 30 KT LOW-LEVEL JET DEVELOPS. THE 00 UTC GUIDANCE ALL SHOWS A GRADIENT IN NEGATIVE SHOWALTER INDICES NORMAL TO THAT LOW- LEVEL JET TOO...WHICH CAN OFTEN BE A GOOD FORECAST SIGNAL FOR SOME NOCTURNAL STORMS. HOWEVER...HEIGHTS ALOFT WILL BE RISING TOO...AND THE SUBSIDENCE ASSOCIATED WITH THAT PROCESS CAN DETER DEVELOPMENT. THUS...WE LEFT A DRY FORECAST IN TACT TONIGHT. NOTE THOUGH THAT WE ALREADY HAD LOW POPS IN BAKER AND EKALAKA FROM 12 TO 18 UTC ON MON AND THUS THOSE WERE LEFT IN PLAY. MON...A MID-LEVEL THERMAL RIDGE WITH 700-HPA TEMPERATURES FROM +11 TO +13 C WILL CROSS THE AREA...LEADING TO HIGHS WELL INTO THE 80S. MIXING MAY BE SUFFICIENT FOR A CRACK AT 90 F...ESPECIALLY IN SOUTH CENTRAL MT. GUIDANCE AGREES THAT A LEE TROUGH AND SURFACE LOW WILL FORM OVER THE AREA...AND SOUTH-SOUTHEAST FLOW SHOULD HAVE A CHANCE OF PULLING HIGHER DEWPOINTS INTO SOUTHEASTERN MT. MOST MODELS SHOW SURFACE DEWPOINTS OF 55 TO 60 F AROUND BAKER AND EKALAKA BENEATH A PLUME OF STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 8 C/KM. ONLY ONE MEMBER OF THE 21 UTC SREF HAS LESS THAN 1800 J/KG OF MLCAPE ACROSS THAT AREA BY PEAK HEATING...AND MOST HAVE VALUES OF 2500 J/KG JUST LIKE THE 00 UTC NAM AND ECMWF SUPPORT. SURFACE HEATING WILL LIKELY BE ENOUGH TO REMOVE MLCIN...BUT FORCING IS IN QUESTION SINCE THERE MAY NOT BE MUCH LOW-LEVEL MASS CONVERGENCE IN PLACE. THE CHANCE OF SEVERE STORMS DRIVEN BY EXPECTED MLCAPE AND VEERING /THOUGH RATHER MODEST/ WIND PROFILES IS THUS HIGHLY CONDITIONAL ON STORMS GETTING GOING IN THE FIRST PLACE. MEANWHILE...WE WILL ALSO HAVE CHANCES OF SOME WEAKER AND HIGH-BASED STORMS ELSEWHERE...ESPECIALLY CLOSER TO LIVINGSTON WHERE HEIGHTS ALOFT WILL FALL A BIT BY 00 UTC. SCHULTZ .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... OVERALL THEME OF THE EXTENDED REMAINS IN TACT WITH A RIDGE PROGGED TO BUILD TO END THE WEEK INTO NEXT WEEKEND. THE TIMING OF MID LEVEL HEIGHT INCREASES KEEPS BEING DELAYED LITTLE BY LITTLE. A SHORTWAVE TROUGH WILL MOVE THROUGH THE AREA EARLY IN THE DAY. TIMING OF THE WAVE MAY LIMIT CONVECTION CHANCES BUT WILL KEEP SCATTERED POPS IN AS STILL A FEW DAYS OUT TO GET THE TIMING OF THIS WAVE DOWN. THE SHORTWAVE ZIPS EAST AND VEERS THE FLOW TO THE WEST FOR ZONAL FLOW WEDNESDAY. THIS WILL SET UP A PERIOD OF DRY WEATHER AS THE UPPER RIDGE TO THE SOUTH STARTS TO BUILD IN EARNEST WEDNESDAY NIGHT. WILL HAVE TO WATCH RIDGE RIDING SHORTWAVES FROM FRIDAY ONWARD AS THE TAP TO PACIFIC MOISTURE MAY BE ENOUGH TO TRIGGER CONVECTION. LOW LEVEL FLOW LOOKS TO BE EASTERLY DURING THIS PERIOD WHICH WILL KEEP DEWPOINTS UP. LIMITING FACTOR FOR CONVECTION WILL BE THE STRENGTH OF THE RIDGE ITSELF. WILL KEEP POPS OUT FRIDAY. DID ADD THEM SATURDAY AS BOTH THE GFS AND ECMWF WERE FAIRLY AGGRESSIVE IN SLIDING A CHUNK OF ENERGY WITH MID LEVEL MOISTURE INTO THE AREA. THE MAIN BUILDING OF THE RIDGE HAS HELD OFF UNTIL EARLY NEXT WEEK AND THE MODELS WERE HAVING DIFFICULTY WITH CONSISTENCY ON THIS. THE CONSENSUS DOES SEEM TO BE TO DELAY THE HIGHER HEIGHTS AND TO SHIFT THE AXIS INTO THE GREAT BASIN. THIS POSITION WOULD KEEP THE POSSIBILITY OF BACK DOOR COOL FRONTS IN PLAY AND WOULD SUPPRESS MONSOONAL TYPE OF MOISTURE FROM WRAPPING INTO THE STATE. TWH && .AVIATION... VFR CONDITIONS WILL PREVAIL ACROSS ALL FLIGHT TERMINALS TODAY THROUGH TONIGHT. RICHMOND && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 078 053/088 062/086 058/087 059/088 059/089 059/090 1/U 11/B 23/T 21/B 10/U 00/U 02/T LVM 078 044/085 054/081 053/083 052/084 053/085 053/086 1/B 13/T 34/T 21/B 11/U 11/U 12/T HDN 080 051/089 059/088 057/089 059/090 059/091 059/093 1/U 11/B 23/T 21/B 11/U 10/U 01/U MLS 078 056/089 062/088 060/088 059/087 060/087 060/089 1/U 12/T 23/T 21/B 10/U 01/U 11/U 4BQ 078 052/089 059/089 058/090 059/090 059/089 059/090 1/U 12/T 22/T 21/U 11/U 11/U 11/U BHK 075 053/086 059/086 058/085 059/084 058/084 061/085 1/B 13/T 32/T 21/U 11/U 10/U 01/U SHR 078 049/086 055/086 053/087 054/087 053/088 053/089 1/U 11/B 22/T 21/B 11/U 11/U 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
331 AM MDT SUN JUN 23 2013 .SHORT TERM...VALID FOR TDY AND MON... A WARMING TREND IS IN STORE TODAY AND MON IN THE WAKE OF THE SHORT WAVE TROUGH WHICH BROUGHT MOISTURE SAT. OUR ATTENTION WILL TURN TO A CONDITIONAL RISK OF SEVERE STORMS IN SOUTHEASTERN MT BY MON AS A PLUME OF HIGHER BOUNDARY LAYER MOISTURE TRIES TO MAKE A RUN TOWARD AT LEAST BAKER JUST AS 500-HPA FLOW BECOMES SOUTHWEST ONCE MORE. TODAY...A DRYING AND WELL-MIXED AIR MASS WILL YIELD A WARM DAY. WE HAVE HIGHS A BIT ABOVE THE 00 UTC MULTI-MODEL CONSENSUS OVER PARTS OF THE AREA IN RESPECT TO EXPECTED MIXING...WHICH SHOULD EXTEND TO 600 HPA IN SOUTH CENTRAL MT AND 700 HPA IN SOUTHEASTERN MT. ONLY A LOW POP WAS RETAINED IN BAKER THIS MORNING. WE ALSO WENT WITHOUT A MENTION OF FOG...AS VISIBILITIES OVER SOUTHEASTERN MT HAVE COME UP SINCE 06 UTC AS WINDS BECAME WEST-SOUTHWEST. HRRR OUTPUT ALSO SAYS MOST OF THE FOG WILL STAY NORTH AND EAST OF THE AREA THIS MORNING. TONIGHT...A QUIET PERIOD IS IN STORE FOR MOST OF THE AREA...BUT WE WILL NEED TO CONSIDER THE POTENTIAL FOR ELEVATED CONVECTION ACROSS SOUTHEASTERN MT WITH LATER FORECASTS. SERIOUS THOUGHT WAS GIVEN TO ADDING SOME LOW POPS FOR STORMS AFTER 09 UTC TO AT LEAST BAKER AND EKALAKA AS A 30 KT LOW-LEVEL JET DEVELOPS. THE 00 UTC GUIDANCE ALL SHOWS A GRADIENT IN NEGATIVE SHOWALTER INDICES NORMAL TO THAT LOW- LEVEL JET TOO...WHICH CAN OFTEN BE A GOOD FORECAST SIGNAL FOR SOME NOCTURNAL STORMS. HOWEVER...HEIGHTS ALOFT WILL BE RISING TOO...AND THE SUBSIDENCE ASSOCIATED WITH THAT PROCESS CAN DETER DEVELOPMENT. THUS...WE LEFT A DRY FORECAST IN TACT TONIGHT. NOTE THOUGH THAT WE ALREADY HAD LOW POPS IN BAKER AND EKALAKA FROM 12 TO 18 UTC ON MON AND THUS THOSE WERE LEFT IN PLAY. MON...A MID-LEVEL THERMAL RIDGE WITH 700-HPA TEMPERATURES FROM +11 TO +13 C WILL CROSS THE AREA...LEADING TO HIGHS WELL INTO THE 80S. MIXING MAY BE SUFFICIENT FOR A CRACK AT 90 F...ESPECIALLY IN SOUTH CENTRAL MT. GUIDANCE AGREES THAT A LEE TROUGH AND SURFACE LOW WILL FORM OVER THE AREA...AND SOUTH-SOUTHEAST FLOW SHOULD HAVE A CHANCE OF PULLING HIGHER DEWPOINTS INTO SOUTHEASTERN MT. MOST MODELS SHOW SURFACE DEWPOINTS OF 55 TO 60 F AROUND BAKER AND EKALAKA BENEATH A PLUME OF STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 8 C/KM. ONLY ONE MEMBER OF THE 21 UTC SREF HAS LESS THAN 1800 J/KG OF MLCAPE ACROSS THAT AREA BY PEAK HEATING...AND MOST HAVE VALUES OF 2500 J/KG JUST LIKE THE 00 UTC NAM AND ECMWF SUPPORT. SURFACE HEATING WILL LIKELY BE ENOUGH TO REMOVE MLCIN...BUT FORCING IS IN QUESTION SINCE THERE MAY NOT BE MUCH LOW-LEVEL MASS CONVERGENCE IN PLACE. THE CHANCE OF SEVERE STORMS DRIVEN BY EXPECTED MLCAPE AND VEERING /THOUGH RATHER MODEST/ WIND PROFILES IS THUS HIGHLY CONDITIONAL ON STORMS GETTING GOING IN THE FIRST PLACE. MEANWHILE...WE WILL ALSO HAVE CHANCES OF SOME WEAKER AND HIGH-BASED STORMS ELSEWHERE...ESPECIALLY CLOSER TO LIVINGSTON WHERE HEIGHTS ALOFT WILL FALL A BIT BY 00 UTC. SCHULTZ .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... OVERALL THEME OF THE EXTENDED REMAINS IN TACT WITH A RIDGE PROGGED TO BUILD TO END THE WEEK INTO NEXT WEEKEND. THE TIMING OF MID LEVEL HEIGHT INCREASES KEEPS BEING DELAYED LITTLE BY A LITTLE. A SHORTWAVE TROUGH WILL MOVE THROUGH THE AREA EARLY IN THE DAY. TIMING OF THE WAVE MAY LIMIT CONVECTION CHANCES BUT WILL KEEP SCATTERED POPS IN AS STILL A FEW DAYS OUT TO GET THE TIMING OF THIS WAVE DOWN. THE SHORTWAVE ZIPS EAST AND VEERS THE FLOW TO THE WEST FOR ZONAL FLOW WEDNESDAY. THIS WILL SET UP A PERIOD OF DRY WEATHER AS THE UPPER RIDGE TO THE SOUTH STARTS TO BUILD IN EARNEST WEDNESDAY NIGHT. WILL HAVE TO WATCH RIDGE RIDING SHORTWAVES FROM FRIDAY ONWARD AS THE TAP TO PACIFIC MOISTURE MAY BE ENOUGH TO TRIGGER CONVECTION. LOW LEVEL FLOW LOOKS TO BE EASTERLY DURING THIS PERIOD WHICH WILL KEEP DEWPOINTS UP. LIMITING FACTOR FOR CONVECTION WILL BE THE STRENGTH OF THE RIDGE ITSELF. WILL KEEP POPS OUT FRIDAY. DID ADD THEM SATURDAY AS BOTH THE GFS AND ECMWF WERE FAIRLY AGGRESSIVE IN SLIDING A CHUNK OF ENERGY WITH MID LEVEL MOISTURE INTO THE AREA. THE MAIN BUILDING OF THE RIDGE HAS HELD OFF UNTIL EARLY NEXT WEEK AND THE MODELS WERE HAVING DIFFICULTY WITH CONSISTENCY ON THIS. THE CONSENSUS DOES SEEM TO BE TO DELAY THE HIGHER HEIGHTS AND TO SHIFT THE AXIS INTO THE GREAT BASIN. THIS POSITION WOULD KEEP THE POSSIBILITY OF BACK DOOR COOL FRONTS IN PLAY AND WOULD SUPPRESS MONSOONAL TYPE OF MOISTURE FROM WRAPPING INTO THE STATE. TWH && .AVIATION... ISOLATED MORNING SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO LOCATIONS NORTH AND EAST OF A KMLS TO KBHK LINE. THERE IS A POSSIBILITY OF MVFR CONDITIONS IN A HEAVIER SHOWER BUT VFR IS EXPECTED TO BE PREDOMINATE. THE CHANCE OF PRECIPITATION WILL EXIT THIS AFTERNOON. THE REST OF THE AREA WILL HAVE A MOSTLY SUNNY SKY WITH LIGHT WIND. TWH && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 078 053/088 062/086 058/087 059/088 059/089 059/090 1/U 11/B 23/T 21/B 10/U 00/U 02/T LVM 078 044/085 054/081 053/083 052/084 053/085 053/086 1/B 13/T 34/T 21/B 11/U 11/U 12/T HDN 080 051/089 059/088 057/089 059/090 059/091 059/093 1/U 11/B 23/T 21/B 11/U 10/U 01/U MLS 078 056/089 062/088 060/088 059/087 060/087 060/089 1/B 12/T 23/T 21/B 10/U 01/U 11/U 4BQ 078 052/089 059/089 058/090 059/090 059/089 059/090 1/U 12/T 22/T 21/U 11/U 11/U 11/U BHK 075 053/086 059/086 058/085 059/084 058/084 061/085 2/W 13/T 32/T 21/U 11/U 10/U 01/U SHR 078 049/086 055/086 053/087 054/087 053/088 053/089 1/U 11/B 22/T 21/B 11/U 11/U 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
325 PM CDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 317 PM CDT SUN JUN 23 2013 MORNING MAP ANALYSIS INDICATES QUASI ZONAL TO SOUTHWESTERLY MID TO UPPER LEVEL FLOW OVER THE WESTERN HALF OF THE CONUS...WITH A LONGWAVE RIDGE OVER THE EAST. A COUPLE OF MID LEVEL SHORT WAVES ARE ALSO NOTED...WITH ONE EXTENDING FROM THE UPPER MISSISSIPPI VALLEY INTO THE NORTHERN PLAINS...AND THE OTHER OVER THE SOUTHWESTERN CONUS. MID TO UPPER LEVEL JET ENERGY EXTENDS FROM THE WEST/SOUTHWESTERN CONUS...EAST/NORTHEAST INTO THE CENTRAL PLAINS...AND THEN NORTH INTO SOUTH CENTRAL CANADA BEFORE FLOWING EAST INTO SOUTHEASTERN CANADA AND PORTIONS OF THE NORTHEASTERN CONUS. MID TO UPPER LEVEL FLOW OVER OUR AREA MAXES OUT AT AROUND 60KTS BETWEEN 300MB AND 200MB PER 12Z SOUNDING DATA FROM KLBF AND KOAX. WATER VAPOR IMAGERY ALSO SHOWS THE AFOREMENTIONED MID LEVEL SHORT WAVES...ALONG WITH A PAIR OF CLOSED MID LEVEL LOWS. ONE SUCH LOW IS LOCATED OVER EASTERN ALBERTA AND WESTERN SASKATCHEWAN...AND THE OTHER IS OVER THE PACIFIC JUST OFF THE COAST OF THE NORTHWESTERN CONUS. AT THE SURFACE AN AREA OF LOW BAROMETRIC PRESSURE EXISTS OVER SOUTHWESTERN KANSAS...WITH A FRONTAL BOUNDARY EXTENDING NORTHEAST FROM THE LOW INTO NORTH CENTRAL KANSAS AND SOUTHEASTERN NEBRASKA. THE LOW LEVEL WIND FIELD ACROSS MUCH OF OUR CWA REMAINS FROM THE NORTHEAST FOR THE MOST PART...BUT LOCATIONS ACROSS OUR SOUTHEAST SUCH AS KK82...KK61...AND KHJH ARE ALL OBSERVING A SURFACE WIND FROM THE SOUTHEAST. GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN SUGGESTS THE LOW LEVEL BAROCLINIC ZONE WILL PERSIST OVER SOUTHEASTERN PORTIONS OF OUR CWA THIS EVENING INTO TONIGHT BEFORE SURGING NORTH DURING THE DAY MONDAY. THERE ARE INDICATIONS...ESPECIALLY FROM HIGHER RESOLUTION MODELS SUCH AS THE NAM12...OF VERY SUBTLE MID LEVEL PERTURBATIONS MOVING OVERHEAD WITHIN THE MEAN FLOW THIS AFTERNOON AND THIS EVENING. CONFIDENCE ON SUCH A FEATURE PROMOTING PRECIPITATION PRODUCTION ACROSS OUR AREA THIS AFTERNOON AND EVENING REMAINS VERY LOW HOWEVER AND AS A RESULT...WILL CONTINUE RELEGATING ANY AFTERNOON AND EVENING POPS TO OUR SOUTH/SOUTHEASTERN CWA...IN CLOSEST PROXIMITY TO THE AFOREMENTIONED LOW LEVEL BAROCLINIC ZONE AND RESULTANT AXIS OF ENHANCED LOW LEVEL CONVERGENCE AND LIFT. AS FOR THE TIMING OF CONVECTIVE INITIATION THIS AFTERNOON AND EVENING...FORECAST PROXIMITY SOUNDINGS FROM THE NAM...OPERATIONAL GFS...AND RAP ALL SUGGEST A HEALTHY CAP PERSISTING THROUGH AT LEAST 00Z. GIVEN THIS...ITS HARD TO BUY INTO QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN...WHICH ALL SUGGEST WIDESPREAD PRECIPITATION WILL BE REALIZED ACROSS PORTIONS OF OUR SOUTHEAST BEFORE 00Z THIS EVENING. HRRR SIMULATED REFLECTIVITY LOOKS MUCH MORE REASONABLE...SUGGESTING VERY ISOLATED CONVECTION OCCURRING ACROSS OUR SOUTHEAST TOWARDS 00Z. GIVEN ALL THIS...CONFIDENCE IS VERY LOW THAT MUCH PRECIPITATION WILL BE REALIZED ACROSS OUR AREA PRIOR TO 00Z...BUT CANNOT COMPLETELY RULE OUT SUCH A SOLUTION AND WILL MAINTAIN ~20% POPS ACROSS OUR SOUTHEAST 23-00Z. 00Z AND BEYOND...FORECAST PROXIMITY SOUNDINGS SUGGEST THE CAPPING INVERSION WILL WEAKEN SOMEWHAT THUS MAKING CONVECTION SOMEWHAT MORE LIKELY...A SOLUTION SUPPORTED BY QPF FIELDS FROM THE NAM...OPERATIONAL GFS...EC...AND SREF-MEAN...AS WELL AS SIMULATED REFLECTIVITY FROM THE HRRR. GIVEN THIS...WILL GO AHEAD WITH SLIGHTLY HIGHER POPS...~%30...00-06Z ACROSS OUR SOUTHEAST. SHOULD SURFACE-BASED CONVECTION BE REALIZED THIS AFTERNOON AND/OR EVENING...THEN SEVERE WEATHER WILL LIKELY RESULT WITH DEEP LAYER MUCAPE VALUES IN THE 2000-4000J/KG WAITING FOR UPDRAFT PRODUCTION AND 30-35KTS OF DEEP LAYER BULK SHEAR FOR UPDRAFT ENHANCEMENT. CERTAINLY LARGE HAIL AND MICROBURST-RELATED WIND GUSTS WILL BE A THREAT...BUT ENHANCED HORIZONTAL VORTICITY IN THE VICINITY OF THE LOW LEVEL BAROCLINIC ZONE COULD ALSO PROMOTE ISOLATED TORNADIC ACTIVITY. WILL CONTINUE SUCH WORDING IN THE HWO AS A RESULT. HEADING INTO THE OVERNIGHT HOURS TONIGHT...THE AXIS OF A ~45KT 850MB JET STREAK IS EXPECTED TO DEVELOP ACROSS PORTIONS OF WESTERN AND CENTRAL KANSAS...WITH THE NOSE OF THIS LOW LEVEL JET MOVING INTO SOUTHERN PORTIONS OF OUR CWA BETWEEN 06Z AND 12Z. SHOULD DEEP CONVECTION BE ONGOING ALONG THE LOW LEVEL BAROCLINIC ZONE...THEN INCREASING LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF THE LOW LEVEL JET COULD CERTAINLY HELP INCREASE SPATIAL COVERAGE OF SAID CONVECTIVE ACTIVITY. ALSO...IN ADDITION TO POSSIBLE THUNDERSTORM ACTIVITY OVER PORTIONS OF OUR CWA THIS AFTERNOON AND EVENING...THUNDERSTORMS ALSO REMAIN POSSIBLE OVER THE CENTRAL HIGH PLAINS. SHOULD HIGH PLAINS CONVECTION DEVELOP THIS AFTERNOON/EVENING AND MOVE EAST TOWARDS OUR AREA TONIGHT...ADDITIONAL SHOWER AND THUNDERSTORM ACTIVITY COULD BE REALIZED OVER OUR AREA TONIGHT...ESPECIALLY OUR WEST. THIS IS A SOLUTION SUPPORTED BY THE NAM...OPERATIONAL GFS...SREF-MEAN...AND HRRR. GIVEN ALL THIS...WENT AHEAD WITH RELATIVELY HIGHER POPS ACROSS MUCH OF THE CWA STARTING AROUND 06Z. SEVERE WEATHER COULD CERTAINLY BE POSSIBLE DURING THE EARLY PART OF THE OVERNIGHT HOURS AS THE MORE ROBUST CONVECTION FROM EARLIER IN THE EVENING...SHOULD IT DEVELOP...MAINTAINS ITSELF. THAT BEING SAID...BARRING THE DEVELOPMENT OF AN MCS ACROSS THE REGION...CONVECTIVE ACTIVITY SHOULD WANE IN INTENSITY AS POTENTIAL INSTABILITY DECREASES 06Z ONWARD. THERE COULD SOME LINGERING SHOWER AND THUNDERSTORM ACTIVITY ACROSS OUR AREA AROUND SUNRISE MONDAY...BUT OTHERWISE MONDAY DURING THE DAY IS EXPECTED TO REMAIN DRY FOR THE MOST PART AS THE WARM FRONT SURGES NORTH AND AN OVERALL LACK IN KINEMATIC FORCING OVERTAKES THE AREA. AT THIS TIME THE ONLY REAL THREAT FOR PRECIPITATION DURING THE DAY MONDAY APPEARS AS THOUGH IT WILL RESIDE OVER OUR SOUTHWESTERN CWA DURING THE LATE AFTERNOON AND EVENING HOURS...WHICH IS WHERE AND WHEN GUIDANCE SUGGESTS AN ADVANCING LOW LEVEL DRY LINE WILL BULGE EAST. AN AREA OF LOCALLY ENHANCED CONVERGENCE AND LIFT IN THE VICINITY OF THIS DRY LINE BULGE...WORKING IN CONCERT WITH DIABATIC HEATING...MAY BE ENOUGH TO INITIALIZE ISOLATED SHOWER AND THUNDERSTORM DEVELOPMENT AND AS A RESULT...~20% POPS ARE FORECAST 21Z MONDAY THROUGH 00Z TUESDAY ACROSS OUR SOUTHWEST. SHOULD THUNDERSTORM ACTIVITY BE REALIZED LATE MONDAY AFTERNOON AND/OR EVENING...THEN DEEP LAYER MUCAPE VALUES OF 2000-3000J/KG...ALONG WITH DEEP LAYER BULK SHEAR VALUES OF ~30KTS...WILL BE AVAILABLE FOR UPDRAFT PRODUCTION AND ENHANCEMENT. GIVEN THIS...WILL GO AHEAD AND HIGHLIGHT THE THREAT FOR ISOLATED SEVERE WEATHER ACROSS OUR SOUTHWEST MONDAY AFTERNOON AND EVENING. FINALLY...INCREASING SOUTHERLY FLOW WILL LIKELY BE OBSERVED MONDAY AFTERNOON ONCE THE SURFACE WARM FRONT SURGES NORTH. GUIDANCE SUGGESTS A SUSTAINED WIND OF ~24KTS...WITH HIGHER GUSTS APPROACHING 35KTS...WILL BE REALIZED PRIMARILY ACROSS NORTH CENTRAL KANSAS. AS A RESULT...WILL CONTINUE MENTIONING SUCH CONDITIONS IN THE HWO. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 317 PM CDT SUN JUN 23 2013 MONDAY NIGHT...A VORT MAX LOCATED OVER THE HIGH PLAINS WILL TRACK EAST ACROSS THE FORECAST AREA. THUNDERSTORMS THAT INITIALLY FORM ACROSS THE HIGH PLAINS DURING THE MONDAY AFTERNOON HOURS WILL SLIDE EAST DURING THE EVENING AND OVERNIGHT HOURS...AND IF THEY HOLD TOGETHER MAY BRING RAIN TO PORTIONS OF THE FORECAST AREA. IN ADDITION TO RAIN...SOME OF THESE THUNDERSTORMS MAY BE SEVERE WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE DURING THE EVENING HOURS. INSTABILITY IS HIGH AND DEEP LAYER SHEAR IS MORE MODEST BUT SUFFICIENT FOR SEVERE STORMS. THE LIMITING FACTOR WILL BE THE WARM MID LEVEL CAP AND THUS CONFIDENCE IN THUNDERSTORM DEVELOPMENT AND COVERAGE IS STILL FAIRLY LOW WITH SLIGHT POPS. THE 12Z ECMWF AND 12Z NAM FAVOR OUR WEST AND NORTH FOR STORMS...WHILE THE 12Z GFS HIGHLIGHTS OUR SOUTHEASTERN ZONES. THE ECMWF AND NAM MAKE MORE SENSE WITH FAVORING NORTH AND WEST ZONES BASED ON THE EXPECTED UPPER WAVE LOCATION AND THE INCREASING STRENGTH OF THE CAP AS YOU HEAD SOUTH. TUESDAY AND WEDNESDAY...THE PATTERN WILL BE FAIRLY ZONAL WITH ALL OF THE BETTER UPPER FLOW AND SHORT WAVES TRACKING ACROSS THE NORTHERN TIER STATES. AN UPPER RIDGE WILL SLOWLY BEGIN TO BUILD ACROSS THE SOUTHWEST CONUS STARTING ON WEDNESDAY. A SFC TROUGH AXIS WILL TRACK EAST THROUGH OUR FORECAST AREA LATE ON TUESDAY AND TURN THE WINDS TO NORTHERLY BY WEDNESDAY. HOWEVER...A STRONG CAP SHOULD RESULT IN DRY CONDITIONS FOR MOST AREAS AND WILL CONTINUE TO CALL FOR A DRY FORECAST...BUT CAN NOT COMPLETELY RULE OUT AN ISOLATED THUNDERSTORM...HENCE THE 10 PERCENT POPS. TUESDAY WILL BE SCORCHER WITH HIGHS WELL INTO THE 90S ACROSS NEBRASKA TO OVER 100 ACROSS MUCH OF NORTHERN KANSAS. TEMPERATURES WILL FALL A FEW DEGREES WITH THE NORTH WINDS ON WEDNESDAY...BUT CONTINUE TO EXPECT 90S FOR HIGHS. THURSDAY THROUGH SUNDAY...THERE IS A SHIFT IN THE UPPER PATTERN AS AN UPPER RIDGE STRENGTHENS ACROSS THE ROCKIES AND AN UPPER TROUGH PERSISTS ACROSS THE EASTERN CONUS. THIS WILL RESULT IN NORTHWESTERLY FLOW ALOFT FOR OUR FORECAST AREA. MOST AREAS WILL BE DRY THROUGHOUT THIS PERIOD GIVEN A LACK OF FORCING. THERE IS A SLIGHT CHANCE OF THUNDERSTORMS ON THURSDAY INTO THURSDAY NIGHT...BUT MOST RESENT MODEL RUNS ARE STARTING TO BACK OFF OF THIS ALREADY RATHER SLIGHT CHANCE OF PRECIPITATION. ANOTHER WEAK COOL FRONT WILL TRY TO WORK ITS WAY THROUGH AT SOME POINT THURSDAY NIGHT OR FRIDAY...BUT THURSDAY SHOULD STILL BE A HOT DAY WITH 90S ACROSS NEBRASKA TO NEAR 100 IN KANSAS. THE COOLER WEATHER WILL SETTLE IN ON FRIDAY AND SATURDAY WITH EASTERLY TO NORTHEASTERLY SFC WINDS. THIS COOLER FETCH SHOULD DROP HIGHS BACK INTO THE LOWER AND MID 90S ON FRIDAY...AND THEN 80S ACROSS NEBRASKA TO LOWER 90S OVER KANSAS ON SATURDAY. TEMPERATURES BEGIN TO WARM BACK UP ON SUNDAY WITH EVERYONE BACK IN THE 90S. OVERALL...TEMPERATURES WILL NOT VARY THAT MUCH AND REMAIN RATHER TOASTY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1246 PM CDT SUN JUN 23 2013 TEMPORARY MVFR CONDITIONS FORECAST THROUGH 19Z...WITH PREVAILING VFR CONDITIONS OTHERWISE FORECAST THROUGH THE NEXT 24 HOURS. A PERIODIC CEILING NEAR 2000FT AGL CONTINUES TO APPEAR AT KGRI. AS DIABATIC HEATING CONTINUES TO INCREASE HOWEVER...ANY LINGERING STRATUS SHOULD BREAK APART AND INCREASE IN HEIGHT...WITH PREVAILING VFR CONDITIONS EXPECTED BY 19Z. PASSING CLOUDS...WITH BASES BETWEEN 3000FT AGL AND 8000FT AGL WILL THEN REMAIN POSSIBLE THROUGH THE REMAINDER OF THE TAF PERIOD....WITH SCATTERED CLOUDS CLOSER TO 15000FT AGL ALSO FORECAST. THERE IS A LOW CHANCE FOR SHOWER AND THUNDERSTORM ACTIVITY AT KGRI THROUGH TONIGHT. THE PROBABILITY OF SUCH CONDITIONS BEING OBSERVED AT KGRI IS TOO LOW FOR INSERTION INTO THE TAF AT THIS TIME HOWEVER. THE SURFACE WIND WILL REMAIN LIGHT AND VARIABLE FOR THE MOST PART THROUGH TONIGHT BEFORE BECOMING MORE ESTABLISHED FROM THE SOUTHEAST MONDAY MORNING. THE AXIS OF A LOW LEVEL JET...WITH SUSTAINED WINDS NEAR 45KTS...IS EXPECTED TO DEVELOP OVER PORTIONS OF KANSAS TONIGHT. AT THIS TIME IT APPEARS THIS LOW LEVEL JET WILL REMAIN FAR ENOUGH SOUTH THUS PREVENTING THE DEVELOPMENT OF LOW LEVEL WIND SHEAR AT KGRI. THAT BEING SAID...THE DEVELOPMENT OF THIS LOW LEVEL JET WILL NEED TO BE MONITORED TO ENSURE IT DOES NOT MOVE FARTHER NORTH THAN CURRENTLY FORECAST...OTHERWISE LOW LEVEL WIND SHEAR COULD POTENTIALLY BE OBSERVED AT KGRI OVERNIGHT TONIGHT. VISIBILITY RESTRICTION IS NOT EXPECTED AT KGRI THROUGH THE NEXT 24 HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...BRYANT LONG TERM...WESELY AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1221 AM CDT SUN JUN 23 2013 .AVIATION... 06Z TAFS FOR KOFK...KOMA AND KLNK. CONVECTION MOVING THROUGH CENTRAL NEBRASKA WAS SENDING AN OUTFLOW BOUNDARY TOWARD EASTERN NEBRASKA...THUS INCLUDED A WIND GUST MENTION WITH TEMPO TSTM GROUP EARLY IN TAF PERIOD AT ALL SITES. CONVECTION DEVELOPING BEHIND LEADING LINE IN SW NEBR COULD MOVE ACROSS TAF SITES SUNDAY MORNING AND THIS WILL HAVE TO BE MONITORED FOR POSSIBLE INCLUSION LATER. HOWEVER...WITH INITIAL FORECAST ONLY CARRIED A FEW HOUR WINDOW WITH INITIAL THUNDERSTORM SURGE. GUSTY SOUTH SOUTHEAST SFC WINDS HAVE DEVELOPED AHEAD OF CONVECTION WILL LIKELY TURN VARIABLE AFTER CONVECTION PASSES THROUGH. THIS CONVECTION SHOULD AID IN A WEAK FRONT PUSHING THROUGH KOFK SUNDAY MIDDAY WITH NNW WINDS BEHIND IT. AHEAD OF BOUNDARY SRLY WINDS AND A PROB30 GROUP WAS CARRIED AT KOMA/KLNK FOR ADDITIONAL TSTORM DEVELOPMENT LATE SUNDAY AFTERNOON/EVENING. CHERMOK && .PREV DISCUSSION... /ISSUED 343 PM CDT SAT JUN 22 2013/ DISCUSSION... THUNDERSTORM CHANCES THROUGH SUNDAY OR MONDAY...THEN WARMING NEXT WEEK...REMAIN THE PRIMARY FORECAST CONCERNS. THUNDERSTORMS THAT DEVELOPED IN WESTERN NEBRASKA FRIDAY AFTERNOON/EVENING HELD TOGETHER OVERNIGHT FUELED BY THETA-E ADVECTION ON NOSE OF LOW LEVEL JET. STORMS SWEPT ACROSS MUCH OF EASTERN NEBRASKA AND WEST CENTRAL IOWA DURING THE MORNING BUT HAD DECREASED MARKEDLY BY LATE MORNING. ATTENDANT CLOUD SHIELD HELD TEMPERATURES DOWN MUCH OF THE MORNING...BUT RETURNING SOUTH WINDS AND MORE SUNSHINE THIS AFTERNOON PUSHED TEMPERATURES TOWARD OR ABOVE 90 IN ALL BUT NORTHEAST NEBRASKA WHERE TEMPS LAGGED IN THE UPPER 70S OR LOWER 80S. DEW POINTS WERE BETWEEN 65 AND 70. LOOKS LIKE MORNING CONVECTION HAS STABILIZED ATMOSPHERE FOR LATE AFTERNOON ACTIVITY FOR THE MOST PART. RAP MESOANALYSIS SHOWS MUCAPE VALUES WELL OVER 2000 J/KG IN THE SOUTHERN HALF OF THE CWA...BUT LOW LEVEL CONVERGENCE IS NEGLIGIBLE. MEANWHILE IN THE NORTHEAST WHERE SOME SURFACE CONVERGENCE IS NOTED...COOLER SURFACE TEMPS BEHIND EXITING CONVECTION HAS KEPT MUCAPE LOW. EXPECT THAT TO ERODE LATER THIS EVENING AS A MID LEVEL IMPULSE MOVING OUT OF EASTERN COLORADO/WYOMING COOLS MID LEVEL ATMOSPHERE AS SURFACE TEMPERATURES REBOUND SOMEWHAT. BETTER CHANCES FOR EVENING CONVECTION LIES TO OUR WEST WHERE CAPES ARE INCREASING AND CAP DIMINISHING...AND LATEST MESO DISCUSSIONS FROM SPC SUGGEST WATCH IS LIKELY FOR PARTS OF WESTERN AND CENTRAL NEBRASKA. THESE STORMS WILL MOVE NORTHEAST TOWARD NORTHEAST NEBRASKA...THEN PROPAGATE SOUTHEAST WITH TIME AS LOW LEVEL JET KICKS IN OVERNIGHT...PROBABLY REACHING THE I-80 CORRIDOR LATE TONIGHT. SEVERE THREAT SHOULD WANE AFTER MIDNIGHT...BUT ANY OF THE STRONGER STORMS COULD PRODUCE WIND AND POSSIBLY HAIL AS FREEZING LEVELS HAVE COME DOWN SOME FROM YESTERDAY. WOULD EXPECT A DECREASING TREND AGAIN SUNDAY MORNING...THEN REDEVELOPMENT IN THE AFTERNOON ALONG COLD FRONT THAT WILL BE DRIFTING INTO THE NORTHWEST CWA IN THE MORNING. WHERE THAT FRONT WILL SET UP WILL BE AFFECTED BY MORNING CONVECTION...BUT MOST LIKELY WILL LIE SOMEWHERE CLOSE TO I-80 CORRIDOR IN THE AFTERNOON. SUNSHINE AND POOLING DEW POINTS ALONG FRONT WILL YIELD CAPES CLOSE TO 3000 J/KG ALONG WITH 30KT 0-6KM SHEAR. FRONTAL CONVERGENCE UNDER STEEP LAPSE RATES NEAR 8 C/KM SUGGEST STORMS WILL FIRE LATE IN THE DAY AS CAP WEAKENS. ALL MODES OF SEVERE ARE POSSIBLE...AS SHEAR/INSTABILITY AND LOWERING FREEZING LEVELS POINT TO WIND AND HAIL. AND LOW LEVEL VORTICITY/HELICITY/EHI SUPPORT AN ISOLATED TORNADO THREAT. EXPECT STORMS TO CONTINUE THROUGH THE EVENING WITH SEVERE THREAT GRADUALLY DIMINISHING LATE IN THE EVENING. AGAIN ANOTHER ROUND OF STORMS FROM THE HIGH PLAINS MAY ROLL ACROSS NORTHERN CWA AFTER MIDNIGHT. AFTER MORNING CONVECTION MONDAY...MUCH OF NEXT WEEK LOOKS DRY AS HEIGHTS BUILD FROM THE SOUTHWEST AND SOUTH INTO THE CENTRAL PLAINS. HOWEVER ANOTHER ROUND OF STORMS MONDAY AFTERNOON...BUT WOULD FAVOR AREAS NORTH OF NEBRASKA. BY LATE IN THE WEEK...A MID LEVEL TROUGH DEEPENING NEAR AND NORTH OF THE GREAT LAKES COULD DRIVE A BACKDOOR COLD FRONT INTO OUR AREA. MODELS REMAIN BEARISH WITH PRECIP CHANCES THEN...BUT SLIGHTLY COOLER AIR WILL FOLLOW. LOOKS LIKE HIGHS IN THE 90S WILL BE COMMON THROUGH MUCH OF THE WEEK...WITH 80S FRIDAY AND SATURDAY. DERGAN && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ 99/99
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1132 AM MDT SUN JUN 23 2013 .AVIATION... 18Z TAF CYCLE VFR CIGS AND VIZ NEXT 24 HOURS. AFTERNOON ISOLD CONVECTION DVLPG AFTER 20Z OVER EXTREME SOUTHEAST NM NEAR TX BORDER...AND IN NORTHEAST CORNER OF NM NEAR OK PANHANDLE. TURBULENT SOUTHWEST FLOW CONTINUING ALOFT AS SURFACE LOW PRESSURE DEEPENS OVER THE OK PANHANDLE AND EXTENDS TROUGH ACROSS EASTERN NM TO WEST TX BIG BEND COUNTRY. GUSTY SOUTHWEST WINDS DEVELOPING AFTER 19Z THIS AFTERNOON WILL BE TYPICALLY G25KTS...WITH G30KTS IN TAF FOR LVS OVER EAST SLOPES OF THE SANGRE DE CRISTO RANGE AND CENTRAL MT CHAIN. SPEEDS DECREASING AFTER 03Z SUNSET TONIGHT. SIMILAR WIND REGIME ON TAP FROM 16Z ONWARD MON MORNING. SHY && .PREV DISCUSSION...320 AM MDT SUN JUN 23 2013... .DISCUSSION.. DRY LINE HAS MADE LESS PROGRESS WESTWARD ATTM THAN IN PREVIOUS NIGHTS...AND AT 3 AM WAS STRETCHED FROM KROW NORTHEAST TO NEAR KCAO. AT THE SAME TIME...A BOUNDARY FROM APPARENTLY THE CONVECTIVE COMPLEX OVER WRN NE AND KS...OR AT LEAST AIDED BY IT...HAD SAGGED TO KLHX AND KLAA. LATEST RUC13 INDICATES THE BOUNDARY COULD REACH KTCC OR EVEN FARTHER SOUTH BY MID MORNING...AND BY EARLY AFTERNOON IT COULD BE STRETCHED FROM THE RATON AREA TO KTCC. 06Z NAM MAKES FOR AN INTERESTING FORECAST WITH THE SURFACE LOW REMAINING CENTERED NEAR KLVS RATHER THAN LIFTING INTO NE CO LATE THIS AFTERNOON. THIS CHANGE COULD RESULT IN A LITTLE LESS WIND...AS WELL AS A LITTLE MORE AREAL COVERAGE OF THE SLIGHT CHANCE POPS WE CURRENTLY HAVE PAINTED IN FAR NE NM. OTHERWISE...SHOULD BE LESS HIGH CLOUDS AROUND TODAY WITH LITTLE CHANGE IN HIGH TEMPERATURES FOR MOST LOCALES. WINDS TO BE A BIT STRONGER MONDAY...SHUNTING ANY MID LEVEL MOISTURE THAT TRIES TO WORK IT/S WAY NORTHWARD INTO SOUTHERN AND EASTERN SECTIONS OF THE STATE...ALTHOUGH IT/S NOW FORECAST TO BE SOMEWHAT LESS THAN PREVIOUS MODEL RUNS SUGGESTED...AND SEEPAGE INTO SOUTHWEST NM APPEARS LESS LIKELY. STILL THERE IS PLENTY OF MOISTURE JUST SOUTH OF THE BORDER SO LEFT POPS PRETTY MUCH ALONE. DRY LINE CAN/T SEEM TO MAKE MUCH PROGRESS WESTWARD FOR THE NEXT FEW DAYS WITH THE LEE TROUGH STAYING PUT. UPPER HIGH REMAINS PROGGED TO SHIFT NORTHWARD BY TUESDAY ALLOWING WINDS TO RELAX...HEADING FOR THE FOUR CORNERS REGION MID TO LATE WEEK. WEDNESDAY INTO THURSDAY COULD BE THE HOTTEST DAYS OF THE WEEK FOR THE CENTRAL AND WEST. EVIDENCE OF A FRONT INVADING THE EASTERN PLAINS FRIDAY-ISH COULD SPARK SHOWERS AND STORMS IN THE NORTH CENTRAL/EAST. BY NEXT WEEKEND...THE HIGH CENTER STARTS TRIPPING TOWARD SALT LAKE...WITH POTENTIAL FOR CONVECTION TO DEVELOP OVER THE NRN HIGH TERRAIN AND DRIFT SOUTH TO SOUTHWESTWARD INTO CENTRAL/WRN VALLEYS. .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS EXPECTED OVER MUCH OF CENTRAL TO EASTERN NM TODAY WITH MORE WIDESPREAD CONDITIONS ON MONDAY... TODAY`S FORECAST WILL BE TRICKY...ESPECIALLY WITH REGARDS TO THE WINDS. THIS WILL HAVE LARGE IMPLICATIONS ON THE DURATION AND SPATIAL EXTENT OF CRITICAL FIRE WEATHER THIS AFTERNOON. OVERALL...THE MAIN FEATURES THAT HAVE BEEN DICTATING THE WEATHER PATTERN THE PAST FEW DAYS ARE STILL AT WORK...WITHOUT ANY BLATANT OR LARGE CHANGES. ANY DIFFERENCES WILL BE FAIRLY SUBTLE. HOWEVER...MIXING HEIGHTS MAY EXCEED YESTERDAY`S LEVELS DUE TO LESS HIGH CIRRUS CLOUDS. MODEL DEPICTION OF MIXING HEIGHTS IS RATHER SPLOTCHY...INDICATIVE THAT IT IS HAVING DIFFICULTY RESOLVING IT. ALSO...SOUTHWESTERLIES ALOFT REMAIN RELATIVELY STRONG FOR LATE JUNE...HOSTING SPEEDS OF 15-20 KT AT H7 AND UP TO 20-25 KT AT H5 WHICH SHOULD BE WITHIN THE MIXED LAYER OF MOST SITES. THE EASTERN HALF OF THE FORECAST AREA WILL ALSO HAVE POTENTIAL FOR A BETTER SURFACE PRESSURE GRADIENT...DEPENDING ON WHERE THE LEE SIDE SURFACE LOW ESTABLISHES ITSELF. A CLUSTER OF CONVECTION IN THE CENTRAL PLAINS OF THE NATION HAS HELPED USHER A BOUNDARY SOUTHWARD INTO COLORADO. IF THIS BOUNDARY SPILLS FARTHER SOUTH INTO NM...BEYOND WHAT MOST MODELS ARE INDICATING...IT COULD WREAK HAVOC ON WIND FORECAST DUE TO ORIENTATION OF THE SURFACE LOW AND ASSOCIATED GRADIENT. HUMIDITY WILL TANK LESS THAN 10 PERCENT OVER MOST OF THE FORECAST AREA TODAY WITH THE FAR EASTERN PLAINS NEAR TX BEING THE ONLY EXCEPTION. HIGHLY UNSTABLE AND WELL-MIXED AIR MASS WOULD SEEM TO SUPPORT A GUSTY DAY FOR MUCH OF THE AREA...AND BEST CONFIDENCE FOR CRITICAL WINDS EXTENDS ALONG AND EAST OF A SOCORRO TO CLINES CORNERS TO RATON LINE...EXCLUDING SOME OF THE FAR PLAINS ALONG THE OK/TX BORDERS. HAVE THROWN IN MIDDLE RIO GRANDE FWZ106 TO THE WARNING. WOULD NOT BE SURPRISED TO SEE A COUPLE OF STRAY GUSTS TO 35 MPH IN THE WEST CENTRAL ZONES...BUT CONFIDENCE IS NOT HIGH ENOUGH TO PULL TRIGGER ON WARNING. CONFIDENCE IS A BIT HIGHER ON MONDAY DUE TO STRONGER WIND SIGNALS SUCH AS BETTER AGREEMENT ON THE SURFACE LOW PLACEMENT AND STRONGER WINDS ALOFT OF 20 TO 35 KT IN THE H7-H5 LAYER. VERY DRY AIR MASS ALOFT AND REINFORCEMENT FROM A MID LEVEL DRY SLOT WILL MAKE ANOTHER EXTREMELY LOW RH REGIME WITH POOR RECOVERIES MONDAY MORNING AND PROLONGED SINGLE DIGIT READINGS. HAVE EXTENDED WATCH FOR MONDAY TO INCLUDE MIDDLE RIO GRANDE AND NORTHWESTERN AND WEST CENTRAL HIGHLANDS/MOUNTAINS. HAVE LEFT NORTHERN MOUNTAINS AND NORTHWEST PLATEAU OUT DUE TO LOWER CONFIDENCE IN THE WINDS...BUT THIS WILL NEED TO BE SCRUTINIZED OVER THE NEXT 24 HOURS. THE WINDS ALOFT DO RELAX SOME INTO TUESDAY AS THE UPPER HIGH BEGINS TO DRIFT NORTHWARD. STILL...A SUFFICIENT LEE SIDE SURFACE LOW WILL KEEP SOME BREEZY/WINDY CONDITIONS GOING IN THE EAST...PRIMARILY NEAR THE I-40 CORRIDOR. INTO WEDNESDAY AND THROUGH THE REST OF THE WEEK THE UPPER HIGH WILL ESTABLISH ITSELF OVER THE DESERT SOUTHWEST...PERIODICALLY CENTERING NEAR OR CLOSE TO THE FOUR CORNERS. THIS WILL SPELL DRY AND HOT CONDITIONS...BUT WITH LOW WINDS. MOISTURE MAY FINALLY BEGIN TO ARRIVE FROM THE EAST BY THE WEEKEND AS A BACK DOOR FRONT AND ONSHORE FLOW FROM THE GULF OF MEXICO SEEP IN. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR THE FOLLOWING ZONES...NMZ102>104-106>108. FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR THE FOLLOWING ZONES...NMZ102>109. && $$ 43/99
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
541 AM MDT SUN JUN 23 2013 .AVIATION... 12Z TAF CYCLE WINDS WILL INCREASE THIS AFTERNOON WITH SOME GUSTS BETWEEN 25 TO 30 KT. VFR CONDITIONS WILL PREVAIL OUTSIDE OF ANY SHOWER/STORMS. ANY PRECIPITATION WILL BE CONFINED WELL INTO THE FAR EASTERN PLAINS NEAR THE TX/OK BORDERS WHERE SHOWERS AND STORMS WILL PRODUCE LOCAL ENHANCEMENTS TO THE GUSTY WINDS. WINDS WILL DIMINISH MOST LOCATIONS AFTER SUNSET...BUT WILL REMAIN PERSISTENTLY STRONG IN THE EASTERN PLAINS THROUGH THE EVENING AND INTO THE EARLY MORNING MONDAY. 52 && .PREV DISCUSSION...320 AM MDT SUN JUN 23 2013... .DISCUSSION.. DRYLINE HAS MADE LESS PROGRESS WESTWARD ATTM THAN IN PREVIOUS NIGHTS...AND AT 3 AM WAS STRETCHED FROM KROW NORTHEAST TO NEAR KCAO. AT THE SAME TIME...A BOUNDARY FROM APPARENTLY THE CONVECTIVE COMPLEX OVER WRN NE AND KS...OR AT LEAST AIDED BY IT...HAD SAGGED TO KLHX AND KLAA. LATEST RUC13 INDICATES THE BOUNDARY COULD REACH KTCC OR EVEN FARTHER SOUTH BY MIDMORNING...AND BY EARLY AFTERNOON IT COULD BE STRETCHED FROM THE RATON AREA TO KTCC. 06Z NAM MAKES FOR AN INTERESTING FORECAST WITH THE SURFACE LOW REMAINING CENTERED NEAR KLVS RATHER THAN LIFTING INTO NE CO LATE THIS AFTERNOON. THIS CHANGE COULD RESULT IN A LITTLE LESS WIND...AS WELL AS A LITTLE MORE AREAL COVERAGE OF THE SLIGHT CHANCE POPS WE CURRENTLY HAVE PAINTED IN FAR NE NM. OTHERWISE...SHOULD BE LESS HIGH CLOUDS AROUND TODAY WITH LITTLE CHANGE IN HIGH TEMPERATURES FOR MOST LOCALES. WINDS TO BE A BIT STRONGER MONDAY...SHUNTING ANY MID LEVEL MOISTURE THAT TRIES TO WORK IT/S WAY NORTHWARD INTO SOUTHERN AND EASTERN SECTIONS OF THE STATE...ALTHOUGH IT/S NOW FORECAST TO BE SOMEWHAT LESS THAN PREVIOUS MODEL RUNS SUGGESTED...AND SEEPAGE INTO SOUTHWEST NM APPEARS LESS LIKELY. STILL THERE IS PLENTY OF MOISTURE JUST SOUTH OF THE BORDER SO LEFT POPS PRETTY MUCH ALONE. DRYLINE CAN/T SEEM TO MAKE MUCH PROGRESS WESTWARD FOR THE NEXT FEW DAYS WITH THE LEE TROUGH STAYING PUT. UPPER HIGH REMAINS PROGGED TO SHIFT NORTHWARD BY TUESDAY ALLOWING WINDS TO RELAX...HEADING FOR THE FOUR CORNERS REGION MID TO LATE WEEK. WEDNESDAY INTO THURSDAY COULD BE THE HOTTEST DAYS OF THE WEEK FOR THE CENTRAL AND WEST. EVIDENCE OF A FRONT INVADING THE EASTERN PLAINS FRIDAY-ISH COULD SPARK SHOWERS AND STORMS IN THE NORTH CENTRAL/EAST. BY NEXT WEEKEND...THE HIGH CENTER STARTS TRIPPING TOWARD SALT LAKE...WITH POTENTIAL FOR CONVECTION TO DEVELOP OVER THE NRN HIGH TERRAIN AND DRIFT SOUTH TO SOUTHWESTWARD INTO CENTRAL/WRN VALLEYS. .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS EXPECTED OVER MUCH OF CENTRAL TO EASTERN NM TODAY WITH MORE WIDESPREAD CONDITIONS ON MONDAY... TODAY`S FORECAST WILL BE TRICKY...ESPECIALLY WITH REGARDS TO THE WINDS. THIS WILL HAVE LARGE IMPLICATIONS ON THE DURATION AND SPATIAL EXTENT OF CRITICAL FIRE WEATHER THIS AFTERNOON. OVERALL...THE MAIN FEATURES THAT HAVE BEEN DICTATING THE WEATHER PATTERN THE PAST FEW DAYS ARE STILL AT WORK...WITHOUT ANY BLATANT OR LARGE CHANGES. ANY DIFFERENCES WILL BE FAIRLY SUBTLE. HOWEVER...MIXING HEIGHTS MAY EXCEED YESTERDAY`S LEVELS DUE TO LESS HIGH CIRRUS CLOUDS. MODEL DEPICTION OF MIXING HEIGHTS IS RATHER SPLOTCHY...INDICATIVE THAT IT IS HAVING DIFFICULTY RESOLVING IT. ALSO...SOUTHWESTERLIES ALOFT REMAIN RELATIVELY STRONG FOR LATE JUNE...HOSTING SPEEDS OF 15-20 KT AT H7 AND UP TO 20-25 KT AT H5 WHICH SHOULD BE WITHIN THE MIXED LAYER OF MOST SITES. THE EASTERN HALF OF THE FORECAST AREA WILL ALSO HAVE POTENTIAL FOR A BETTER SURFACE PRESSURE GRADIENT...DEPENDING ON WHERE THE LEE SIDE SURFACE LOW ESTABLISHES ITSELF. A CLUSTER OF CONVECTION IN THE CENTRAL PLAINS OF THE NATION HAS HELPED USHER A BOUNDARY SOUTHWARD INTO COLORADO. IF THIS BOUNDARY SPILLS FARTHER SOUTH INTO NM...BEYOND WHAT MOST MODELS ARE INDICATING...IT COULD WREAK HAVOC ON WIND FORECAST DUE TO ORIENTATION OF THE SURFACE LOW AND ASSOCIATED GRADIENT. HUMIDITY WILL TANK LESS THAN 10 PERCENT OVER MOST OF THE FORECAST AREA TODAY WITH THE FAR EASTERN PLAINS NEAR TX BEING THE ONLY EXCEPTION. HIGHLY UNSTABLE AND WELL-MIXED AIRMASS WOULD SEEM TO SUPPORT A GUSTY DAY FOR MUCH OF THE AREA...AND BEST CONFIDENCE FOR CRITICAL WINDS EXTENDS ALONG AND EAST OF A SOCORRO TO CLINES CORNERS TO RATON LINE...EXCLUDING SOME OF THE FAR PLAINS ALONG THE OK/TX BORDERS. HAVE THROWN IN MIDDLE RIO GRANDE FWZ106 TO THE WARNING. WOULD NOT BE SURPRISED TO SEE A COUPLE OF STRAY GUSTS TO 35 MPH IN THE WEST CENTRAL ZONES...BUT CONFIDENCE IS NOT HIGH ENOUGH TO PULL TRIGGER ON WARNING. CONFIDENCE IS A BIT HIGHER ON MONDAY DUE TO STRONGER WIND SIGNALS SUCH AS BETTER AGREEMENT ON THE SURFACE LOW PLACEMENT AND STRONGER WINDS ALOFT OF 20 TO 35 KT IN THE H7-H5 LAYER. VERY DRY AIRMASS ALOFT AND REINFORCEMENT FROM A MID LEVEL DRY SLOT WILL MAKE ANOTHER EXTREMELY LOW RH REGIME WITH POOR RECOVERIES MONDAY MORNING AND PROLONGED SINGLE DIGIT READINGS. HAVE EXTENDED WATCH FOR MONDAY TO INCLUDE MIDDLE RIO GRANDE AND NORTHWESTERN AND WEST CENTRAL HIGHLANDS/MOUNTAINS. HAVE LEFT NORTHERN MOUNTAINS AND NORTHWEST PLATEAU OUT DUE TO LOWER CONFIDENCE IN THE WINDS...BUT THIS WILL NEED TO BE SCRUTINIZED OVER THE NEXT 24 HOURS. THE WINDS ALOFT DO RELAX SOME INTO TUESDAY AS THE UPPER HIGH BEGINS TO DRIFT NORTHWARD. STILL...A SUFFICIENT LEE SIDE SURFACE LOW WILL KEEP SOME BREEZY/WINDY CONDITIONS GOING IN THE EAST...PRIMARILY NEAR THE I-40 CORRIDOR. INTO WEDNESDAY AND THROUGH THE REST OF THE WEEK THE UPPER HIGH WILL ESTABLISH ITSELF OVER THE DESERT SOUTHWEST...PERIODICALLY CENTERING NEAR OR CLOSE TO THE FOUR CORNERS. THIS WILL SPELL DRY AND HOT CONDITIONS...BUT WITH LOW WINDS. MOISTURE MAY FINALLY BEGIN TO ARRIVE FROM THE EAST BY THE WEEKEND AS A BACK DOOR FRONT AND ONSHORE FLOW FROM THE GULF OF MEXICO SEEP IN. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING FOR THE FOLLOWING ZONES...NMZ102>104-106>108. FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR THE FOLLOWING ZONES...NMZ102>109. && $$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
320 AM MDT SUN JUN 23 2013 .DISCUSSION.. DRYLINE HAS MADE LESS PROGRESS WESTWARD ATTM THAN IN PREVIOUS NIGHTS...AND AT 3 AM WAS STRETCHED FROM KROW NORTHEAST TO NEAR KCAO. AT THE SAME TIME...A BOUNDARY FROM APPARENTLY THE CONVECTIVE COMPLEX OVER WRN NE AND KS...OR AT LEAST AIDED BY IT...HAD SAGGED TO KLHX AND KLAA. LATEST RUC13 INDICATES THE BOUNDARY COULD REACH KTCC OR EVEN FARTHER SOUTH BY MIDMORNING...AND BY EARLY AFTERNOON IT COULD BE STRETCHED FROM THE RATON AREA TO KTCC. 06Z NAM MAKES FOR AN INTERESTING FORECAST WITH THE SURFACE LOW REMAINING CENTERED NEAR KLVS RATHER THAN LIFTING INTO NE CO LATE THIS AFTERNOON. THIS CHANGE COULD RESULT IN A LITTLE LESS WIND...AS WELL AS A LITTLE MORE AREAL COVERAGE OF THE SLIGHT CHANCE POPS WE CURRENTLY HAVE PAINTED IN FAR NE NM. OTHERWISE...SHOULD BE LESS HIGH CLOUDS AROUND TODAY WITH LITTLE CHANGE IN HIGH TEMPERATURES FOR MOST LOCALES. WINDS TO BE A BIT STRONGER MONDAY...SHUNTING ANY MID LEVEL MOISTURE THAT TRIES TO WORK IT/S WAY NORTHWARD INTO SOUTHERN AND EASTERN SECTIONS OF THE STATE...ALTHOUGH IT/S NOW FORECAST TO BE SOMEWHAT LESS THAN PREVIOUS MODEL RUNS SUGGESTED...AND SEEPAGE INTO SOUTHWEST NM APPEARS LESS LIKELY. STILL THERE IS PLENTY OF MOISTURE JUST SOUTH OF THE BORDER SO LEFT POPS PRETTY MUCH ALONE. DRYLINE CAN/T SEEM TO MAKE MUCH PROGRESS WESTWARD FOR THE NEXT FEW DAYS WITH THE LEE TROUGH STAYING PUT. UPPER HIGH REMAINS PROGGED TO SHIFT NORTHWARD BY TUESDAY ALLOWING WINDS TO RELAX...HEADING FOR THE FOUR CORNERS REGION MID TO LATE WEEK. WEDNESDAY INTO THURSDAY COULD BE THE HOTTEST DAYS OF THE WEEK FOR THE CENTRAL AND WEST. EVIDENCE OF A FRONT INVADING THE EASTERN PLAINS FRIDAY-ISH COULD SPARK SHOWERS AND STORMS IN THE NORTH CENTRAL/EAST. BY NEXT WEEKEND...THE HIGH CENTER STARTS TRIPPING TOWARD SALT LAKE...WITH POTENTIAL FOR CONVECTION TO DEVELOP OVER THE NRN HIGH TERRAIN AND DRIFT SOUTH TO SOUTHWESTWARD INTO CENTRAL/WRN VALLEYS. && .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS EXPECTED OVER MUCH OF CENTRAL TO EASTERN NM TODAY WITH MORE WIDESPREAD CONDITIONS ON MONDAY... TODAY`S FORECAST WILL BE TRICKY...ESPECIALLY WITH REGARDS TO THE WINDS. THIS WILL HAVE LARGE IMPLICATIONS ON THE DURATION AND SPATIAL EXTENT OF CRITICAL FIRE WEATHER THIS AFTERNOON. OVERALL...THE MAIN FEATURES THAT HAVE BEEN DICTATING THE WEATHER PATTERN THE PAST FEW DAYS ARE STILL AT WORK...WITHOUT ANY BLATANT OR LARGE CHANGES. ANY DIFFERENCES WILL BE FAIRLY SUBTLE. HOWEVER...MIXING HEIGHTS MAY EXCEED YESTERDAY`S LEVELS DUE TO LESS HIGH CIRRUS CLOUDS. MODEL DEPICTION OF MIXING HEIGHTS IS RATHER SPLOTCHY...INDICATIVE THAT IT IS HAVING DIFFICULTY RESOLVING IT. ALSO...SOUTHWESTERLIES ALOFT REMAIN RELATIVELY STRONG FOR LATE JUNE...HOSTING SPEEDS OF 15-20 KT AT H7 AND UP TO 20-25 KT AT H5 WHICH SHOULD BE WITHIN THE MIXED LAYER OF MOST SITES. THE EASTERN HALF OF THE FORECAST AREA WILL ALSO HAVE POTENTIAL FOR A BETTER SURFACE PRESSURE GRADIENT...DEPENDING ON WHERE THE LEE SIDE SURFACE LOW ESTABLISHES ITSELF. A CLUSTER OF CONVECTION IN THE CENTRAL PLAINS OF THE NATION HAS HELPED USHER A BOUNDARY SOUTHWARD INTO COLORADO. IF THIS BOUNDARY SPILLS FARTHER SOUTH INTO NM...BEYOND WHAT MOST MODELS ARE INDICATING...IT COULD WREAK HAVOC ON WIND FORECAST DUE TO ORIENTATION OF THE SURFACE LOW AND ASSOCIATED GRADIENT. HUMIDITY WILL TANK LESS THAN 10 PERCENT OVER MOST OF THE FORECAST AREA TODAY WITH THE FAR EASTERN PLAINS NEAR TX BEING THE ONLY EXCEPTION. HIGHLY UNSTABLE AND WELL-MIXED AIRMASS WOULD SEEM TO SUPPORT A GUSTY DAY FOR MUCH OF THE AREA...AND BEST CONFIDENCE FOR CRITICAL WINDS EXTENDS ALONG AND EAST OF A SOCORRO TO CLINES CORNERS TO RATON LINE...EXCLUDING SOME OF THE FAR PLAINS ALONG THE OK/TX BORDERS. HAVE THROWN IN MIDDLE RIO GRANDE FWZ106 TO THE WARNING. WOULD NOT BE SURPRISED TO SEE A COUPLE OF STRAY GUSTS TO 35 MPH IN THE WEST CENTRAL ZONES...BUT CONFIDENCE IS NOT HIGH ENOUGH TO PULL TRIGGER ON WARNING. CONFIDENCE IS A BIT HIGHER ON MONDAY DUE TO STRONGER WIND SIGNALS SUCH AS BETTER AGREEMENT ON THE SURFACE LOW PLACEMENT AND STRONGER WINDS ALOFT OF 20 TO 35 KT IN THE H7-H5 LAYER. VERY DRY AIRMASS ALOFT AND REINFORCEMENT FROM A MID LEVEL DRY SLOT WILL MAKE ANOTHER EXTREMELY LOW RH REGIME WITH POOR RECOVERIES MONDAY MORNING AND PROLONGED SINGLE DIGIT READINGS. HAVE EXTENDED WATCH FOR MONDAY TO INCLUDE MIDDLE RIO GRANDE AND NORTHWESTERN AND WEST CENTRAL HIGHLANDS/MOUNTAINS. HAVE LEFT NORTHERN MOUNTAINS AND NORTHWEST PLATEAU OUT DUE TO LOWER CONFIDENCE IN THE WINDS...BUT THIS WILL NEED TO BE SCRUTINIZED OVER THE NEXT 24 HOURS. THE WINDS ALOFT DO RELAX SOME INTO TUESDAY AS THE UPPER HIGH BEGINS TO DRIFT NORTHWARD. STILL...A SUFFICIENT LEE SIDE SURFACE LOW WILL KEEP SOME BREEZY/WINDY CONDITIONS GOING IN THE EAST...PRIMARILY NEAR THE I-40 CORRIDOR. INTO WEDNESDAY AND THROUGH THE REST OF THE WEEK THE UPPER HIGH WILL ESTABLISH ITSELF OVER THE DESERT SOUTHWEST...PERIODICALLY CENTERING NEAR OR CLOSE TO THE FOUR CORNERS. THIS WILL SPELL DRY AND HOT CONDITIONS...BUT WITH LOW WINDS. MOISTURE MAY FINALLY BEGIN TO ARRIVE FROM THE EAST BY THE WEEKEND AS A BACK DOOR FRONT AND ONSHORE FLOW FROM THE GULF OF MEXICO SEEP IN. 52 && .AVIATION... 06Z TAF CYCLE VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS. DRYLINE IS CURRENTLY RETREATING AND STRONG S/SE WINDS WITH GUSTS NEAR 30KTS ARE ALSO RETURNING EAST OF THE DRYLINE. THESE GUSTS WILL BE POSSIBLE THROUGH APPROXIMATELY 10Z MAINLY ALONG AND EAST OF A KCAO TO KROW LINE. ON SUNDAY...W/SW WINDS WILL INCREASE BY LATE MORNING...WITH GUSTS BETWEEN 20 AND 35KTS LIKELY DURING THE AFTERNOON. DRYLINE SHOULD MIX BACK OUT TO AT LEAST THE TX BORDER...LIMITING TS POTENTIAL TO ALL AREAS EXCEPT PERHAPS ROOSEVELT COUNTY. THE DRYLINE WILL RETREAT AGAIN SUNDAY NIGHT...WITH GUSTY S/SE WINDS RETURNING TO THE EAST OF IT. 34 && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 92 51 92 51 / 0 0 0 5 DULCE........................... 88 40 89 41 / 0 0 5 5 CUBA............................ 87 45 86 45 / 0 0 5 5 GALLUP.......................... 88 45 87 44 / 0 0 5 5 EL MORRO........................ 87 43 86 43 / 0 0 5 5 GRANTS.......................... 89 47 89 46 / 0 0 5 5 QUEMADO......................... 89 47 89 46 / 0 0 5 5 GLENWOOD........................ 96 50 94 55 / 0 0 5 5 CHAMA........................... 80 43 80 43 / 0 0 5 5 LOS ALAMOS...................... 86 54 87 53 / 0 0 5 5 PECOS........................... 82 56 83 55 / 5 5 5 5 CERRO/QUESTA.................... 85 49 84 48 / 0 0 5 5 RED RIVER....................... 80 41 80 41 / 0 0 5 5 ANGEL FIRE...................... 80 42 81 43 / 0 0 5 5 TAOS............................ 87 43 86 43 / 0 0 5 5 MORA............................ 82 51 83 52 / 5 5 5 5 ESPANOLA........................ 92 48 92 49 / 0 0 5 5 SANTA FE........................ 89 50 89 50 / 0 0 5 5 SANTA FE AIRPORT................ 92 52 92 52 / 0 0 5 5 ALBUQUERQUE FOOTHILLS........... 93 60 93 60 / 0 0 5 5 ALBUQUERQUE HEIGHTS............. 96 62 95 62 / 0 0 5 5 ALBUQUERQUE VALLEY.............. 98 55 96 56 / 0 0 5 5 ALBUQUERQUE WEST MESA........... 98 57 95 57 / 0 0 5 5 LOS LUNAS....................... 96 59 97 59 / 0 0 5 5 RIO RANCHO...................... 95 60 95 59 / 0 0 5 5 SOCORRO......................... 101 64 100 64 / 0 0 5 5 SANDIA PARK/CEDAR CREST......... 89 57 91 57 / 0 0 5 5 TIJERAS......................... 92 58 93 57 / 0 0 5 5 MORIARTY/ESTANCIA............... 91 53 91 52 / 5 5 5 5 CLINES CORNERS.................. 89 56 89 55 / 5 5 5 5 GRAN QUIVIRA.................... 92 58 92 58 / 5 5 10 5 CARRIZOZO....................... 93 63 93 64 / 5 5 10 5 RUIDOSO......................... 87 53 87 57 / 10 10 10 20 CAPULIN......................... 90 52 90 51 / 5 5 5 5 RATON........................... 93 53 93 52 / 5 5 5 5 SPRINGER........................ 91 53 92 51 / 5 5 5 5 LAS VEGAS....................... 89 52 90 53 / 5 5 5 5 CLAYTON......................... 96 61 97 61 / 20 10 5 10 ROY............................. 93 58 94 56 / 5 5 5 5 CONCHAS......................... 97 60 98 59 / 5 5 5 10 SANTA ROSA...................... 98 62 98 61 / 0 5 5 10 TUCUMCARI....................... 102 68 103 67 / 5 5 10 10 CLOVIS.......................... 98 64 97 64 / 10 10 20 10 PORTALES........................ 99 65 98 65 / 20 10 20 10 FORT SUMNER..................... 100 66 100 65 / 5 5 10 10 ROSWELL......................... 105 69 104 68 / 20 10 20 10 PICACHO......................... 95 63 96 63 / 10 10 10 10 ELK............................. 90 62 91 63 / 10 10 10 20 && .ABQ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING FOR THE FOLLOWING ZONES...NMZ102>104-106>108. FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR THE FOLLOWING ZONES...NMZ102>109. && $$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
150 PM EDT SUN JUN 23 2013 .SYNOPSIS... WE WILL CONTINUE OUR TREND OF A WARM AND INCREASINGLY HUMID PATTERN. WEAK PASSING DISTURBANCES WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS IN EACH OF THE NEXT SEVERAL DAYS...WITH BEST CHANCES IN THE AFTERNOON HOURS. && .NEAR TERM /THROUGH TONIGHT/... 115 PM UPDATE... CONVECTION ACTIVELY DEVELOPING THIS HR ACROSS THE NORTHERN FINGER LAKES IN LAKE PLAIN IN CLOSE PROXIMITY TO LAKE SHADOW BOUNDARY WHICH NOW EXTENDS WELL INLAND FROM LAKE ERIE. FOR WHAT ITS WORTH...RECENT HRRR RUNS HAVE BEEN SUGGESTING SUCH AN EVALUATION AND ITS NICE TO SEE SHORT TERM HIGH-RES MODEL GUIDANCE ADDING VALUE TO THE NEAR TERM FCST PERIOD. THAT SAID...LATEST SPC DAY-1 OUTLOOK PLACES THE NORTHERN HALF OF THE CWA IN A SLGT RISK FOR SEVERE WITH STRONG WINDS BEING THE BIGGEST THREAT...LIKELY A MANIFESTATION OF FAIRLY PRONOUNCED DRY AIR ALOFT AS EVIDENCED IN VARIOUS 12Z RAOBS. LARGE HAIL ALSO A POSSIBILITY CONSIDERING THE STRONG BUOYANCY ACROSS THE AREA WITH LATEST SPC MESO PAGE SUGGESTING MLCAPE VALUES ON THE ORDER OF 2000-2500 J/KG ACROSS THE AREA. WILL CONTINUE TO MONITOR. 950 AM UPDATE... FCST IN FAIRLY GOOD SHAPE THIS MORNING...ONLY MINOR ADJUSTMENTS NEEDED TO ACCOUNT FOR LATEST TRENDS. THAT SAID...MAIN FOCUS REMAINS CENTERED ON POSSIBLE CONVECTION LATER THIS MORNING/AFTERNOON AS REGION WARMS WELL INTO THE THE MIDDLE TO UPPER 80S IN A MODERATELY MOIST AND UNSTABLE ENVIRONMENT. LATEST OBSERVATIONS ALREADY SHOWING SYR AT 85 THIS HR AND HAVE INCREASED MAX TEMPS UPWARD A DEGREE OR TWO IN SOME LOCATIONS. LATE MORNING WATER VAPOR IMAGERY SHOWING A FAIRLY WELL DEFINED SHEAR AXIS LIFTING NORTH FROM SOUTHERN PENNSYLVANIA ALONG THE NORTHERN PERIPHERY OF AN UPPER LOW THAT CONTINUES SPINNING THIS HR ACROSS THE CENTRAL APPALACHIANS. RUC LAYERED 500-300 MB VORTICITY SHOWS A SERIES OF EMBEDDED VORTICITY MAXIMA SLOWLY CREEPING NORTH TOWARDS OUR AREA. THAT SAID...MAIN UPPER FORCING FOR ANY CONVECTION LATER TODAY WILL LIKELY ARRIVE FROM THESE EMBEDDED FEATURES WITH ADDITIONAL LOW-LEVEL FORCING POSSIBLY BEING SUPPLIED BY INCREASED LOW-LEVEL CONVERGENCE ALONG A WEAK SURFACE TROUGH THAT MODELS FCST TO MOVE THROUGH THE REGION LATER TODAY. LATEST HIGH RES MODELS SUGGEST FAIRLY ISOLATED ACTIVITY DEVELOPING LATER TODAY AND CONSIDERING THAT THE FORCING MECHANISMS ARE FAIR WEAK IN NATURE...HAVE ELECTED TO TRIM BACK POPS INTO THE SCATTERED CATEGORY GOING INTO THE AFTERNOON. ABOVE SAID...12Z BUF RAOB SHOWING A FAIR AMOUNT OF DRY AIR ALOFT WITH STEEP MID-LEVEL LAPSE RATES. CONSIDERING THE AMOUNT OF DRY AIR ALOFT...IF ANY CONVECTION WERE TO DEVELOP...A FEW ROGUE PULSEY TYPE SEVERE STORMS WITH LOCALLY HEAVY RAINS CANNOT BE RULED OUT THANKS FOR WEAK WINDS ALOFT AND SLOW STORM MOVEMENT. WILL CONTINUE TO MONITOR AND UPDATE AS NECESSARY. 645 AM UPDATE... LATEST HIGH RES MODEL RUNS ARE COMING INTO GOOD AGREEMENT NOW ON WAVE BEING ABLE TO INITIATE CONVECTION...INCLUDING THE HRRR...RAP/RUC...AND WRFARW. OPERATIONAL 06Z NAM...00Z GEM...AND EVEN SOMEWHAT THE 06Z GFS CONCUR ON AT LEAST THE GENERAL IDEA. GRIDS HAVE BEEN UPDATED ACCORDINGLY WITH LARGER AREA OF MORE DETERMINISTIC 60-70 PERCENT POPS FROM FINGER LAKES EASTWARD ACROSS THE REMAINDER OF CENTRAL NY ESPECIALLY 18Z-22Z TIME FRAME. ALSO HIGH CHANCE POPS SINKING INTO NORTHERN TIER OF PA 20Z SUN-01Z MON TIME FRAME. PREVIOUS DISCUSSION... AFTER SEVERAL DRY DAYS...AREAS NORTH OF THE NEW YORK THRUWAY FINALLY GOT SOME SCATTERED SHOWERS SATURDAY INTO OVERNIGHT DUE TO THE INCREASINGLY MOIST AIR MASS...AND WEAK PASSING DISTURBANCES ON THE SOUTHERN PERIPHERY OF THE BELT OF WESTERLIES. MORE OF THE AREA WILL GET INVOLVED IN THAT TODAY...THOUGH BEST CHANCES WILL AGAIN BE IN CENTRAL NEW YORK. A LOOSELY DEFINED UPPER LOW IS CURRENTLY SPINNING ON THE KY/TN BORDER...WHILE THE MAIN BELT OF WESTERLIES CARRIES OVER FROM THE UPPER MIDWEST THROUGH THE NORTHERN GREAT LAKES AND INTO NEW ENGLAND. BETWEEN THOSE FEATURES...AN UPPER RIDGE STILL EXTENDS ACROSS THE MID-ATLANTIC STATES BACK TOWARDS THE UPPER OHIO VALLEY. THE UPPER RIDGE IS LOSING ITS GRIP HOWEVER. MODELS DISAGREE ON HOW QUICKLY MOISTURE FILLS THE VOID OF LOWER PRECIPITABLE WATER ALONG THE RIDGE AXIS. IN ASSIGNING POPS TODAY...THE SREF APPEARS WAY OVERDONE...AND UPSTREAM 00Z SUN SOUNDINGS IN BUFFALO NY AND WHITE LAKE MI CONFIRM LOWER PRECIPITABLE WATER VALUES THAN SUGGESTED BY SREF. THAT BEING SAID...THERE WILL DEFINITELY BE A GRADIENT IN RAIN CHANCES. IT CAN BE CONFIDENTLY STATED THAT THE NORTHERN ZONES WILL HAVE PWATS AT LEAST AROUND AN INCH-AND-TWO- THIRDS...VERSUS THE SOUTHERN ZONES WHERE PWATS STAY UNDER AN INCH-AND-A-HALF. IN BETWEEN...ACROSS THE TWIN TIERS...MODELS DISAGREE ON AMOUNT OF MOISTURE AND THUS INSTABILITY. AS A RESULT OF THE HIGHER PWATS...MODEL SOUNDINGS AGREE ON NORTHERN ZONES HAVING MORE INSTABILITY...GREATER THAN 1000 J/KG...YET FARTHER SOUTH IS MORE UNCERTAIN. ALSO...THE NORTHERN ZONES WILL BE MORE PRONE TO SOME ALBEIT LIMITED FORCING FROM WEAK SHORTWAVES. I HAVE KEYED IN ON WEAK VORTICITY WAVE THAT SHOWS UP ON GEM/NAM/WRFARW MODELS WHICH WILL ENTER FINGER LAKES AROUND MIDDAY AND DRIFT EASTWARD FROM THERE IN THE AFTERNOON...HIGH CHANCE TO LIKELY POPS. RESULTANT CONVECTION WILL HAVE A FIGHT AS IT TRIES TO MAKE SOUTHEAST PROGRESS...WITH LESS FRIENDLY AIR MASS...AND THUS LOWER POPS. THOUGH THERE IS FAIR AMOUNT OF CONFIDENCE THAT THE CONVECTIVE SHOWERS WILL CONTAIN THUNDER...SHEAR AND OTHER PARAMETERS ARE LACKING AND THUS NOT EXPECTING ANY ORGANIZED SEVERE THREAT. SPC DAY 1 CONVECTIVE OUTLOOK ONLY HAS A BROAD-BRUSHED 5 PCT CHANCE OF SEVERE IN AN AXIS FROM LOWER MICHIGAN THROUGH PARTS OF OUR REGION AND INTERIOR NEW ENGLAND. MET AND MAV GUIDANCE WAS OVERALL JUST SLIGHTLY TOO WARM WITH TEMPERATURES SATURDAY...AND I SUSPECT THE SAME MAY BE TRUE TODAY CONSIDERING AMOUNT OF MOISTURE AND PROSPECTS FOR SCATTERED CONVECTION. FOR HIGHS I BLENDED MAV/MET WITH THE SLIGHTLY COOLER LAV GUIDANCE. STILL A WARM AND HUMID DAY...WITH HIGHS 80S AREA WIDE AND EVEN SOME LOWER ELEVATION SPOTS NEAR 90. ANOTHER MUGGY NIGHT TONIGHT WITH LOWS IN THE MID TO UPPER 60S. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... 350 AM UPDATE... LEFTOVERS OF UPPER LOW NOW OVER KY/TN BORDER...WILL DRIFT NORTHWARD AROUND COLLAPSING UPPER RIDGE...AND CARRY THROUGH OUR REGION MONDAY. DESPITE THAT LITTLE BIT OF ENERGY...PRECIPITABLE WATER VALUES WILL ACTUALLY BE LOWERING THROUGH THE DAY. DIURNAL HEATING AND MODEST INSTABILITY MOSTLY LESS THAN 1000 J/KG SHOULD ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS...WITH BEST CHANCES GENERALLY FROM CENTRAL SOUTHERN TIER OF NY TO NEPA /THOUGH AT LEAST SOME CHANCE AREA WIDE/. COME TUESDAY...PRECIPITABLE WATER VALUES LOOK TO RETURN ABOVE 1.5 INCHES AND WE WILL ALSO AGAIN BE PENETRATED BY THE BELT OF WESTERLIES AND EMBEDDED WAVES. UNCERTAINTY ON TIMING OF WAVES AND MESOSCALE INFLUENCES PREVENTED ME FROM GOING HIGHER THAN 40-50 PCT POPS...BUT AT LEAST SCATTERED DIURNALLY-DRIVEN CONVECTION LOOKS LIKE A FAIR BET. BOTH MONDAY AND TUESDAY...DAYTIME TEMPERATURES WILL REMAIN ROUGHLY 6 TO 9 DEGREES ABOVE CLIMATOLOGY. DEW POINTS IN ABOUT THE MID 60S MONDAY WILL SNEAK MORE INTO THE UPPER 60S TUESDAY...ALLOWING HEAT INDICES TO ECLIPSE 90 AT LOWER ELEVATIONS. DESPITE THE HEAT AND HUMIDITY...CAPES FAIRLY MODEST AND CONVECTIVE PARAMETERS SUCH AS SHEAR ARE ONLY MARGINAL AT BEST...THUS OPPORTUNITY FOR AN ORGANIZED SEVERE THREAT APPEARS QUITE LOW. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... A FLAT RIDGE WILL EXIST OVER MUCH OF THE EASTERN CONUS THIS PERIOD. IMPULSES WILL ROTATE OVER THE TOP OF THE RIDGE, WHILE WARM/MOIST AIR WILL REMAIN IN PLACE ACROSS NY/PA TYPIFIED BY 850MB TEMPS OF 16C TO 20C. THE RESULT WILL BE A MILD TEMPERATURE PATTERN, WITH THE DAILY THREAT FOR ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCE FOR THUNDERSTORMS WILL BE ON THURSDAY, WHEN A TROF OVER SOUTHERN CANADA DIPS ACROSS THE GREAT LAKES TOWARD LAKE ONTARIO. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... 18Z SUN UPDATE... DVLPG SHRA/TSRA THIS AFTN MAY PROVIDE RESTRICTIVE CONDS AT KSYR/KRME THROUGH ABT 20Z...AND PERHAPS IN THE VICINITY OF KELM/KITH BY 20-22Z. FOR NOW...WE`LL LEAVE MENTION OF ANY RESTRICTIONS OUT OF KBGM/KAVP OVER THE NEAR-TERM...AS TSRA OCCURRENCES ARE MORE UNCERTAIN AT THESE LOCATIONS. OVERNIGHT INTO MON AM...QUIET CONDS OVERALL...BUT SOME LGT FOG/HZ COULD BRING MVFR RESTRICTIONS AT KRME/KITH/KBGM/KAVP AFTER 06Z...WITH SOME LOCALLY DENSE VLY FOG STILL PSBL IN THE VICINITY OF KELM (IFR CONDS). SHRA/TSRA COULD DVLP AGN BY MON AFTN...BUT SCTD COVERAGE PRECLUDES THEIR MENTION IN THE TERMINALS AT THIS EARLY JUNCTURE. OUTLOOK...TUE THROUGH FRI... RESTRICTIONS ARE PSBL EACH DAY...MAINLY IN THE AFTN/EVE...WITH AT LEAST SCTD SHRA/TSRA FORESEEN. PATCHES OF OVERNIGHT/EARLY AM LOW CLDS/FOG ARE ALSO PSBL. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...CMG/MDP SHORT TERM...MDP LONG TERM...DJP AVIATION...MLJ
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
126 PM EDT SUN JUN 23 2013 .SYNOPSIS... WE WILL CONTINUE OUR TREND OF A WARM AND INCREASINGLY HUMID PATTERN. WEAK PASSING DISTURBANCES WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS IN EACH OF THE NEXT SEVERAL DAYS...WITH BEST CHANCES IN THE AFTERNOON HOURS. && .NEAR TERM /THROUGH TONIGHT/... 115 PM UPDATE... CONVECTION ACTIVELY DEVELOPING THIS HR ACROSS THE NORTHERN FINGER LAKES IN LAKE PLAIN IN CLOSE PROXIMITY TO LAKE SHADOW BOUNDARY WHICH NOW EXTENDS WELL INLAND FROM LAKE ERIE. FOR WHAT ITS WORTH...RECENT HRRR RUNS HAVE BEEN SUGGESTING SUCH AN EVALUATION AND ITS NICE TO SEE SHORT TERM HIGH-RES MODEL GUIDANCE ADDING VALUE TO THE NEAR TERM FCST PERIOD. THAT SAID...LATEST SPC DAY-1 OUTLOOK PLACES THE NORTHERN HALF OF THE CWA IN A SLGT RISK FOR SEVERE WITH STRONG WINDS BEING THE BIGGEST THREAT...LIKEY A MANIFESTATION OF FAIRLY PRONOUNCED DRY AIR ALOFT AS EVIDENCED IN VARIOUS 12Z RAOBS. LARGE HAIL ALSO A POSSIBILITY CONSIDERING THE STRONG BUOYANCY ACROSS THE AREA WITH LATEST SPC MESO PAGE SUGGESTING MLCAPE VALUES ON THE ORDER OF 2000-2500 J/KG ACROSS THE AREA. WILL CONTINUE TO MONITOR. 950 AM UPDATE... FCST IN FAIRLY GOOD SHAPE THIS MORNING...ONLY MINOR ADJUSTMENTS NEEDED TO ACCOUNT FOR LATEST TRENDS. THAT SAID...MAIN FOCUS REMAINS CENTERED ON POSSIBLE CONVECTION LATER THIS MORNING/AFTERNOON AS REGION WARMS WELL INTO THE THE MIDDLE TO UPPER 80S IN A MODERATELY MOIST AND UNSTABLE ENVIRONMENT. LATEST OBSERVATIONS ALREADY SHOWING SYR AT 85 THIS HR AND HAVE INCREASED MAX TEMPS UPWARD A DEGREE OR TWO IN SOME LOCATIONS. LATE MORNING WATER VAPOR IMAGERY SHOWING A FAIRLY WELL DEFINED SHEAR AXIS LIFTING NORTH FROM SOUTHERN PENNSYLVANIA ALONG THE NORTHERN PERIPHERY OF AN UPPER LOW THAT CONTINUES SPINNING THIS HR ACROSS THE CENTRAL APPALACHIANS. RUC LAYERED 500-300 MB VORTICITY SHOWS A SERIES OF EMBEDDED VORTICITY MAXIMA SLOWLY CREEPING NORTH TOWARDS OUR AREA. THAT SAID...MAIN UPPER FORCING FOR ANY CONVECTION LATER TODAY WILL LIKELY ARRIVE FROM THESE EMBEDDED FEATURES WITH ADDITIONAL LOW-LEVEL FORCING POSSIBLY BEING SUPPLIED BY INCREASED LOW-LEVEL CONVERGENCE ALONG A WEAK SURFACE TROUGH THAT MODELS FCST TO MOVE THROUGH THE REGION LATER TODAY. LATEST HIGH RES MODELS SUGGEST FAIRLY ISOLATED ACTIVITY DEVELOPING LATER TODAY AND CONSIDERING THAT THE FORCING MECHANISMS ARE FAIR WEAK IN NATURE...HAVE ELECTED TO TRIM BACK POPS INTO THE SCATTERED CATEGORY GOING INTO THE AFTERNOON. ABOVE SAID...12Z BUF RAOB SHOWING A FAIR AMOUNT OF DRY AIR ALOFT WITH STEEP MID-LEVEL LAPSE RATES. CONSIDERING THE AMOUNT OF DRY AIR ALOFT...IF ANY CONVECTION WERE TO DEVELOP...A FEW ROGUE PULSEY TYPE SEVERE STORMS WITH LOCALLY HEAVY RAINS CANNOT BE RULED OUT THANKS FOR WEAK WINDS ALOFT AND SLOW STORM MOVEMENT. WILL CONTINUE TO MONITOR AND UPDATE AS NECESSARY. 645 AM UPDATE... LATEST HIGH RES MODEL RUNS ARE COMING INTO GOOD AGREEMENT NOW ON WAVE BEING ABLE TO INITIATE CONVECTION...INCLUDING THE HRRR...RAP/RUC...AND WRFARW. OPERATIONAL 06Z NAM...00Z GEM...AND EVEN SOMEWHAT THE 06Z GFS CONCUR ON AT LEAST THE GENERAL IDEA. GRIDS HAVE BEEN UPDATED ACCORDINGLY WITH LARGER AREA OF MORE DETERMINISTIC 60-70 PERCENT POPS FROM FINGER LAKES EASTWARD ACROSS THE REMAINDER OF CENTRAL NY ESPECIALLY 18Z-22Z TIME FRAME. ALSO HIGH CHANCE POPS SINKING INTO NORTHERN TIER OF PA 20Z SUN-01Z MON TIME FRAME. PREVIOUS DISCUSSION... AFTER SEVERAL DRY DAYS...AREAS NORTH OF THE NEW YORK THRUWAY FINALLY GOT SOME SCATTERED SHOWERS SATURDAY INTO OVERNIGHT DUE TO THE INCREASINGLY MOIST AIR MASS...AND WEAK PASSING DISTURBANCES ON THE SOUTHERN PERIPHERY OF THE BELT OF WESTERLIES. MORE OF THE AREA WILL GET INVOLVED IN THAT TODAY...THOUGH BEST CHANCES WILL AGAIN BE IN CENTRAL NEW YORK. A LOOSELY DEFINED UPPER LOW IS CURRENTLY SPINNING ON THE KY/TN BORDER...WHILE THE MAIN BELT OF WESTERLIES CARRIES OVER FROM THE UPPER MIDWEST THROUGH THE NORTHERN GREAT LAKES AND INTO NEW ENGLAND. BETWEEN THOSE FEATURES...AN UPPER RIDGE STILL EXTENDS ACROSS THE MIDATLANTIC STATES BACK TOWARDS THE UPPER OHIO VALLEY. THE UPPER RIDGE IS LOSING ITS GRIP HOWEVER. MODELS DISAGREE ON HOW QUICKLY MOISTURE FILLS THE VOID OF LOWER PRECIPITABLE WATER ALONG THE RIDGE AXIS. IN ASSIGNING POPS TODAY...THE SREF APPEARS WAY OVERDONE...AND UPSTREAM 00Z SUN SOUNDINGS IN BUFFALO NY AND WHITE LAKE MI CONFIRM LOWER PRECIPITABLE WATER VALUES THAN SUGGESTED BY SREF. THAT BEING SAID...THERE WILL DEFINITELY BE A GRADIENT IN RAIN CHANCES. IT CAN BE CONFIDENTLY STATED THAT THE NORTHERN ZONES WILL HAVE PWATS AT LEAST AROUND AN INCH-AND-TWO- THIRDS...VERSUS THE SOUTHERN ZONES WHERE PWATS STAY UNDER AN INCH-AND-A-HALF. IN BETWEEN...ACROSS THE TWIN TIERS...MODELS DISAGREE ON AMOUNT OF MOISTURE AND THUS INSTABILITY. AS A RESULT OF THE HIGHER PWATS...MODEL SOUNDINGS AGREE ON NORTHERN ZONES HAVING MORE INSTABILITY...GREATER THAN 1000 J/KG...YET FARTHER SOUTH IS MORE UNCERTAIN. ALSO...THE NORTHERN ZONES WILL BE MORE PRONE TO SOME ALBEIT LIMITED FORCING FROM WEAK SHORTWAVES. I HAVE KEYED IN ON WEAK VORTICITY WAVE THAT SHOWS UP ON GEM/NAM/WRFARW MODELS WHICH WILL ENTER FINGER LAKES AROUND MIDDAY AND DRIFT EASTWARD FROM THERE IN THE AFTERNOON...HIGH CHANCE TO LIKELY POPS. RESULTANT CONVECTION WILL HAVE A FIGHT AS IT TRIES TO MAKE SOUTHEAST PROGRESS...WITH LESS FRIENDLY AIR MASS...AND THUS LOWER POPS. THOUGH THERE IS FAIR AMOUNT OF CONFIDENCE THAT THE CONVECTIVE SHOWERS WILL CONTAIN THUNDER...SHEAR AND OTHER PARAMETERS ARE LACKING AND THUS NOT EXPECTING ANY ORGANIZED SEVERE THREAT. SPC DAY 1 CONVECTIVE OUTLOOK ONLY HAS A BROADBRUSHED 5 PCT CHANCE OF SEVERE IN AN AXIS FROM LOWER MICHIGAN THROUGH PARTS OF OUR REGION AND INTERIOR NEW ENGLAND. MET AND MAV GUIDANCE WAS OVERALL JUST SLIGHTLY TOO WARM WITH TEMPERATURES SATURDAY...AND I SUSPECT THE SAME MAY BE TRUE TODAY CONSIDERING AMOUNT OF MOISTURE AND PROSPECTS FOR SCATTERED CONVECTION. FOR HIGHS I BLENDED MAV/MET WITH THE SLIGHTLY COOLER LAV GUIDANCE. STILL A WARM AND HUMID DAY...WITH HIGHS 80S AREAWIDE AND EVEN SOME LOWER ELEVATION SPOTS NEAR 90. ANOTHER MUGGY NIGHT TONIGHT WITH LOWS IN THE MID TO UPPER 60S. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... 350 AM UPDATE... LEFTOVERS OF UPPER LOW NOW OVER KY/TN BORDER...WILL DRIFT NORTHWARD AROUND COLLAPSING UPPER RIDGE...AND CARRY THROUGH OUR REGION MONDAY. DESPITE THAT LITTLE BIT OF ENERGY...PRECIPITABLE WATER VALUES WILL ACTUALLY BE LOWERING THROUGH THE DAY. DIURNAL HEATING AND MODEST INSTABILITY MOSTLY LESS THAN 1000 J/KG SHOULD ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS...WITH BEST CHANCES GENERALLY FROM CENTRAL SOUTHERN TIER OF NY TO NEPA /THOUGH AT LEAST SOME CHANCE AREAWIDE/. COME TUESDAY...PRECIPITABLE WATER VALUES LOOK TO RETURN ABOVE 1.5 INCHES AND WE WILL ALSO AGAIN BE PENETRATED BY THE BELT OF WESTERLIES AND EMBEDDED WAVES. UNCERTAINTY ON TIMING OF WAVES AND MESOSCALE INFLUENCES PREVENTED ME FROM GOING HIGHER THAN 40-50 PCT POPS...BUT AT LEAST SCATTERED DIURNALLY-DRIVEN CONVECTION LOOKS LIKE A FAIR BET. BOTH MONDAY AND TUESDAY...DAYTIME TEMPERATURES WILL REMAIN ROUGHLY 6 TO 9 DEGREES ABOVE CLIMATOLOGY. DEWPOINTS IN ABOUT THE MID 60S MONDAY WILL SNEAK MORE INTO THE UPPER 60S TUESDAY...ALLOWING HEAT INDICES TO ECLIPSE 90 AT LOWER ELEVATIONS. DESPITE THE HEAT AND HUMIDITY...CAPES FAIRLY MODEST AND CONVECTIVE PARAMETERS SUCH AS SHEAR ARE ONLY MARGINAL AT BEST...THUS OPPORTUNITY FOR AN ORGANIZED SEVERE THREAT APPEARS QUITE LOW. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... A FLAT RIDGE WILL EXIST OVER MUCH OF THE EASTERN CONUS THIS PERIOD. IMPULSES WILL ROTATE OVER THE TOP OF THE RIDGE, WHILE WARM/MOIST AIR WILL REMAIN IN PLACE ACROSS NY/PA TYPIFIED BY 850MB TEMPS OF 16C TO 20C. THE RESULT WILL BE A MILD TEMPERATURE PATTERN, WITH THE DAILY THREAT FOR ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCE FOR THUNDERSTORMS WILL BE ON THURSDAY, WHEN A TROF OVER SOUTHERN CANADA DIPS ACROSS THE GREAT LAKES TOWARD LAKE ONTARIO. && .AVIATION /17Z SUNDAY THROUGH THURSDAY/... ATMOSPHERE WILL DESTABILIZE THIS AFTERNOON WITH CAPES PROJECTED AT 1000-2000 J/KG. A WEAK WAVE WILL DRIFT ACROSS THE REGION, INCREASING THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. LATEST HRRR CONCURS, BRINGING A LINE OF CONVECTION THROUGH CENTRAL NY BETWEEN 18Z AND 22Z. WITH INCREASED CONFIDENCE FOR AFTERNOON CONVECTION...TAFS WILL NOW INCLUDE TEMPO GROUPS FOR THUNDER AT THE NY TERMINALS. OUTLOOK...MON THRU WED...VFR MOST OF THE TIME. MVFR VSBY AND CIG RESTRICTIONS POSSIBLE WITH PASSING SHRA OR TSRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...CMG/MDP SHORT TERM...MDP LONG TERM...DJP AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1009 AM EDT SUN JUN 23 2013 .SYNOPSIS... WE WILL CONTINUE OUR TREND OF A WARM AND INCREASINGLY HUMID PATTERN. WEAK PASSING DISTURBANCES WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS IN EACH OF THE NEXT SEVERAL DAYS...WITH BEST CHANCES IN THE AFTERNOON HOURS. && .NEAR TERM /THROUGH TONIGHT/... 950 AM UPDATE... FCST IN FAIRLY GOOD SHAPE THIS MORNING...ONLY MINOR ADJUSTMENTS NEEDED TO ACCOUNT FOR LATEST TRENDS. THAT SAID...MAIN FOCUS REMAINS CENTERED ON POSSIBLE CONVECTION LATER THIS MORNING/AFTERNOON AS REGION WARMS WELL INTO THE THE MIDDLE TO UPPER 80S IN A MODERATELY MOIST AND UNSTABLE ENVIRONMENT. LATEST OBSERVATIONS ALREADY SHOWING SYR AT 85 THIS HR AND HAVE INCREASED MAX TEMPS UPWARD A DEGREE OR TWO IN SOME LOCATIONS. LATE MORNING WATER VAPOR IMAGERY SHOWING A FAIRLY WELL DEFINED SHEAR AXIS LIFTING NORTH FROM SOUTHERN PENNSYLVANIA ALONG THE NORTHERN PERIPHERY OF AN UPPER LOW THAT CONTINUES SPINNING THIS HR ACROSS THE CENTRAL APPALACHIANS. RUC LAYERED 500-300 MB VORTICITY SHOWS A SERIES OF EMBEDDED VORTICITY MAXIMA SLOWLY CREEPING NORTH TOWARDS OUR AREA. THAT SAID...MAIN UPPER FORCING FOR ANY CONVECTION LATER TODAY WILL LIKELY ARRIVE FROM THESE EMBEDDED FEATURES WITH ADDITIONAL LOW-LEVEL FORCING POSSIBLY BEING SUPPLIED BY INCREASED LOW-LEVEL CONVERGENCE ALONG A WEAK SURFACE TROUGH THAT MODELS FCST TO MOVE THROUGH THE REGION LATER TODAY. LATEST HIGH RES MODELS SUGGEST FAIRLY ISOLATED ACTIVITY DEVELOPING LATER TODAY AND CONSIDERING THAT THE FORCING MECHANISMS ARE FAIR WEAK IN NATURE...HAVE ELECTED TO TRIM BACK POPS INTO THE SCATTERED CATEGORY GOING INTO THE AFTERNOON. ABOVE SAID...12Z BUF RAOB SHOWING A FAIR AMOUNT OF DRY AIR ALOFT WITH STEEP MID-LEVEL LAPSE RATES. CONSIDERING THE AMOUNT OF DRY AIR ALOFT...IF ANY CONVECTION WERE TO DEVELOP...A FEW ROGUE PULSEY TYPE SEVERE STORMS WITH LOCALLY HEAVY RAINS CANNOT BE RULED OUT THANKS FOR WEAK WINDS ALOFT AND SLOW STORM MOVEMENT. WILL CONTINUE TO MONITOR AND UPDATE AS NECESSARY. 645 AM UPDATE... LATEST HIGH RES MODEL RUNS ARE COMING INTO GOOD AGREEMENT NOW ON WAVE BEING ABLE TO INITIATE CONVECTION...INCLUDING THE HRRR...RAP/RUC...AND WRFARW. OPERATIONAL 06Z NAM...00Z GEM...AND EVEN SOMEWHAT THE 06Z GFS CONCUR ON AT LEAST THE GENERAL IDEA. GRIDS HAVE BEEN UPDATED ACCORDINGLY WITH LARGER AREA OF MORE DETERMINISTIC 60-70 PERCENT POPS FROM FINGER LAKES EASTWARD ACROSS THE REMAINDER OF CENTRAL NY ESPECIALLY 18Z-22Z TIME FRAME. ALSO HIGH CHANCE POPS SINKING INTO NORTHERN TIER OF PA 20Z SUN-01Z MON TIME FRAME. PREVIOUS DISCUSSION... AFTER SEVERAL DRY DAYS...AREAS NORTH OF THE NEW YORK THRUWAY FINALLY GOT SOME SCATTERED SHOWERS SATURDAY INTO OVERNIGHT DUE TO THE INCREASINGLY MOIST AIR MASS...AND WEAK PASSING DISTURBANCES ON THE SOUTHERN PERIPHERY OF THE BELT OF WESTERLIES. MORE OF THE AREA WILL GET INVOLVED IN THAT TODAY...THOUGH BEST CHANCES WILL AGAIN BE IN CENTRAL NEW YORK. A LOOSELY DEFINED UPPER LOW IS CURRENTLY SPINNING ON THE KY/TN BORDER...WHILE THE MAIN BELT OF WESTERLIES CARRIES OVER FROM THE UPPER MIDWEST THROUGH THE NORTHERN GREAT LAKES AND INTO NEW ENGLAND. BETWEEN THOSE FEATURES...AN UPPER RIDGE STILL EXTENDS ACROSS THE MIDATLANTIC STATES BACK TOWARDS THE UPPER OHIO VALLEY. THE UPPER RIDGE IS LOSING ITS GRIP HOWEVER. MODELS DISAGREE ON HOW QUICKLY MOISTURE FILLS THE VOID OF LOWER PRECIPITABLE WATER ALONG THE RIDGE AXIS. IN ASSIGNING POPS TODAY...THE SREF APPEARS WAY OVERDONE...AND UPSTREAM 00Z SUN SOUNDINGS IN BUFFALO NY AND WHITE LAKE MI CONFIRM LOWER PRECIPITABLE WATER VALUES THAN SUGGESTED BY SREF. THAT BEING SAID...THERE WILL DEFINITELY BE A GRADIENT IN RAIN CHANCES. IT CAN BE CONFIDENTLY STATED THAT THE NORTHERN ZONES WILL HAVE PWATS AT LEAST AROUND AN INCH-AND-TWO- THIRDS...VERSUS THE SOUTHERN ZONES WHERE PWATS STAY UNDER AN INCH-AND-A-HALF. IN BETWEEN...ACROSS THE TWIN TIERS...MODELS DISAGREE ON AMOUNT OF MOISTURE AND THUS INSTABILITY. AS A RESULT OF THE HIGHER PWATS...MODEL SOUNDINGS AGREE ON NORTHERN ZONES HAVING MORE INSTABILITY...GREATER THAN 1000 J/KG...YET FARTHER SOUTH IS MORE UNCERTAIN. ALSO...THE NORTHERN ZONES WILL BE MORE PRONE TO SOME ALBEIT LIMITED FORCING FROM WEAK SHORTWAVES. I HAVE KEYED IN ON WEAK VORTICITY WAVE THAT SHOWS UP ON GEM/NAM/WRFARW MODELS WHICH WILL ENTER FINGER LAKES AROUND MIDDAY AND DRIFT EASTWARD FROM THERE IN THE AFTERNOON...HIGH CHANCE TO LIKELY POPS. RESULTANT CONVECTION WILL HAVE A FIGHT AS IT TRIES TO MAKE SOUTHEAST PROGRESS...WITH LESS FRIENDLY AIR MASS...AND THUS LOWER POPS. THOUGH THERE IS FAIR AMOUNT OF CONFIDENCE THAT THE CONVECTIVE SHOWERS WILL CONTAIN THUNDER...SHEAR AND OTHER PARAMETERS ARE LACKING AND THUS NOT EXPECTING ANY ORGANIZED SEVERE THREAT. SPC DAY 1 CONVECTIVE OUTLOOK ONLY HAS A BROADBRUSHED 5 PCT CHANCE OF SEVERE IN AN AXIS FROM LOWER MICHIGAN THROUGH PARTS OF OUR REGION AND INTERIOR NEW ENGLAND. MET AND MAV GUIDANCE WAS OVERALL JUST SLIGHTLY TOO WARM WITH TEMPERATURES SATURDAY...AND I SUSPECT THE SAME MAY BE TRUE TODAY CONSIDERING AMOUNT OF MOISTURE AND PROSPECTS FOR SCATTERED CONVECTION. FOR HIGHS I BLENDED MAV/MET WITH THE SLIGHTLY COOLER LAV GUIDANCE. STILL A WARM AND HUMID DAY...WITH HIGHS 80S AREAWIDE AND EVEN SOME LOWER ELEVATION SPOTS NEAR 90. ANOTHER MUGGY NIGHT TONIGHT WITH LOWS IN THE MID TO UPPER 60S. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... 350 AM UPDATE... LEFTOVERS OF UPPER LOW NOW OVER KY/TN BORDER...WILL DRIFT NORTHWARD AROUND COLLAPSING UPPER RIDGE...AND CARRY THROUGH OUR REGION MONDAY. DESPITE THAT LITTLE BIT OF ENERGY...PRECIPITABLE WATER VALUES WILL ACTUALLY BE LOWERING THROUGH THE DAY. DIURNAL HEATING AND MODEST INSTABILITY MOSTLY LESS THAN 1000 J/KG SHOULD ALLOW FOR SCATTERED SHOWERS AND THUNDERSTORMS...WITH BEST CHANCES GENERALLY FROM CENTRAL SOUTHERN TIER OF NY TO NEPA /THOUGH AT LEAST SOME CHANCE AREAWIDE/. COME TUESDAY...PRECIPITABLE WATER VALUES LOOK TO RETURN ABOVE 1.5 INCHES AND WE WILL ALSO AGAIN BE PENETRATED BY THE BELT OF WESTERLIES AND EMBEDDED WAVES. UNCERTAINTY ON TIMING OF WAVES AND MESOSCALE INFLUENCES PREVENTED ME FROM GOING HIGHER THAN 40-50 PCT POPS...BUT AT LEAST SCATTERED DIURNALLY-DRIVEN CONVECTION LOOKS LIKE A FAIR BET. BOTH MONDAY AND TUESDAY...DAYTIME TEMPERATURES WILL REMAIN ROUGHLY 6 TO 9 DEGREES ABOVE CLIMATOLOGY. DEWPOINTS IN ABOUT THE MID 60S MONDAY WILL SNEAK MORE INTO THE UPPER 60S TUESDAY...ALLOWING HEAT INDICES TO ECLIPSE 90 AT LOWER ELEVATIONS. DESPITE THE HEAT AND HUMIDITY...CAPES FAIRLY MODEST AND CONVECTIVE PARAMETERS SUCH AS SHEAR ARE ONLY MARGINAL AT BEST...THUS OPPORTUNITY FOR AN ORGANIZED SEVERE THREAT APPEARS QUITE LOW. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... A FLAT RIDGE WILL EXIST OVER MUCH OF THE EASTERN CONUS THIS PERIOD. IMPULSES WILL ROTATE OVER THE TOP OF THE RIDGE, WHILE WARM/MOIST AIR WILL REMAIN IN PLACE ACROSS NY/PA TYPIFIED BY 850MB TEMPS OF 16C TO 20C. THE RESULT WILL BE A MILD TEMPERATURE PATTERN, WITH THE DAILY THREAT FOR ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCE FOR THUNDERSTORMS WILL BE ON THURSDAY, WHEN A TROF OVER SOUTHERN CANADA DIPS ACROSS THE GREAT LAKES TOWARD LAKE ONTARIO. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... ATMOSPHERE WILL DESTABILIZE THIS AFTERNOON WITH CAPES PROJECTED AT 1000-2000 J/KG. A WEAK WAVE WILL DRIFT ACROSS THE REGION, INCREASING THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. LATEST HRRR CONCURS, BRINGING A LINE OF CONVECTION THROUGH CENTRAL NY BETWEEN 18Z AND 22Z. WITH INCREASED CONFIDENCE FOR AFTERNOON CONVECTION...TAFS WILL NOW INCLUDE TEMPO GROUPS FOR THUNDER AT THE NY TERMINALS. OUTLOOK...MON THRU WED...VFR MOST OF THE TIME. MVFR VSBY AND CIG RESTRICTIONS POSSIBLE WITH PASSING SHRA OR TSRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...MDP NEAR TERM...CMG/MDP SHORT TERM...MDP LONG TERM...DJP AVIATION...DJP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
700 AM EDT SUN JUN 23 2013 .SYNOPSIS... WEAK LOW PRESSURE OVER EASTERN NORTH CAROLINA WILL GRADUALLY DISSIPATE TODAY. A SURFACE TROUGH WILL LINGER OVER THE PIEDMONT THROUGH MID WEEK... AS A WARM AND MOIST AIR MASS HOLDS OVER THE REGION. && .NEAR TERM /THROUGH MONDAY NIGHT/... AS OF 300 AM SUNDAY... THE WAVE OF LOW PRESSURE THAT MOVED THROUGH EASTERN NC LAST EVENING IS NOW MOVING INTO SOUTH CENTRAL VA...AND THE BULK OF HEAVY RAIN ON ITS EASTERN FLANK IS EXITING THE NORTHERN COASTAL PLAIN. IN ITS WAKE...A WEAK BOUNDARY LINGERS NEAR THE I-95 CORRIDOR...WHERE A FEW SHOWERS AND THUNDER STORMS CONTINUE TO DEVELOP. HRRR SIM REFLECTIVITY SUGGEST PRECIP WILL EVENTUALLY SHIFT NORTHWESTWARD INTO THE PIEDMONT THIS MORNING AS AN UPPER LEVEL LOW OVER THE TN VALLEY LIFTS ALONG THE APPALACHIANS. AS THE DAY WEARS ON...A BROAD SOUTH-SOUTHEASTERLY LOW LEVEL FLOW WILL DOMINATE AS THE BERMUDA HIGH BECOMES ESTABLISHED. MOISTURE CONVERGENCE IN THE VICINITY OF THE WEAK BOUNDARY SHOULD BE THE MAIN FOCUS FOR WHAT WILL OTHERWISE BE SCATTERED SHOWERS AND STORMS IN AN ENVIRONMENT CHARACTERIZED BY PW AROUND 1.8 INCHES AND MLCAPE OF 500-1000 J/KG. HIGHS SHOULD REACH THE MID 80S UNDER PARTLY TO MOSTLY CLOUDY SKIES. TONIGHT... A FEW SHOWERS MAY LINGER INTO THE EVENING HOURS...BUT CONVECTION SHOULD BE MOSTLY DIURNAL IN NATURES. LOW CLOUDS ARE EXPECTED ONCE AGAIN OVERNIGHT AND LOWS WILL FALL ONLY INTO THE UPPER 60S. MONDAY AND MONDAY NIGHT... MOIST SOUTHERLY FLOW WILL CONTINUE ON MONDAY WITH UPPER LEVEL HEIGHTS SLOWLY BUILDING OVER THE WESTERN ATLANTIC AND WEST-SOUTHWESTERLY FLOW ALOFT OVER NC. A WEAK LEE TROUGH WILL BEGIN TO DEVELOP OVER THE PIEDMONT...BUT ITS NOT APPARENT HOW MUCH OF A FOCUS THIS WILL BE FOR AFTERNOON CONVECTION. THERMODYNAMICALLY...THE ATMOSPHERE WILL BE VERY SIMILARLY TO SUNDAY...WITH WEAK LAPSE RATES AND MLCAPE POSSIBLY APPROACHING 1000 J/KG ACROSS THE SOUTH AND EAST. PW WILL REMAIN WELL ABOVE 1.5 INCHES...SUGGESTING SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE. HIGHS WILL BE A COUPLE DEGREES WARMER THAN SUNDAY AS THE UPPER RIDGE BUILDS CLOSER TO THE COAST...85-89. LOWS MONDAY NIGHT IN THE UPPER 60S AND LOWER 70S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 240 AM SUNDAY... FOR TUESDAY/TUESDAY NIGHT: THE MID LEVEL ANTICYCLONE NOW CENTERED OVER THE WRN ATLANTIC WILL HAVE EVOLVED INTO A WEAKER BUT MORE EXPANSIVE RIDGE COVERING MUCH OF THE SOUTHERN HALF OF THE COUNTRY (WEST COAST EXCEPTED) BY TUESDAY... RESULTING IN A WEAK WNW STEERING FLOW OVER NC AND POOR DEEP LAYER SHEAR AS THE WESTERLIES RETREAT WELL TO THE NORTH. MODERATE TO POTENTIALLY HIGH INSTABILITY IS EXPECTED BY AFTERNOON WITH GFS-PROJECTED MLCAPE OF 2000-2800 J/KG PARTICULARLY OVER THE EASTERN AND SOUTHERN PORTIONS OF CENTRAL NC... SUPPORTIVE OF AT LEAST SCATTERED SHOWERS AND STORMS WITH DAYTIME HEATING GIVEN PRECIP WATER VALUES OF 1.6-2.0 INCHES... 150-180 PERCENT OF NORMAL. AN MCV INDICATED BY THE MODELS OVER NEB EARLY MONDAY MORNING IS EXPECTED TO TRACK ACROSS MI/IN/OH BY TUESDAY MORNING BEFORE TRACKING ACROSS THE MID ATLANTIC REGION LATE TUESDAY/TUESDAY NIGHT. THIS ADDED DYNAMIC FORCING FOR ASCENT FROM DPVA (ALBEIT WEAK) COULD RESULT IN BETTER COVERAGE OF CONVECTION IN AND NEAR AND EAST OF THE SURFACE LEE TROUGH LATE AFTERNOON THROUGH THE EVENING. WILL GRADUALLY INCREASE POPS THROUGH THE AFTERNOON TO 40-50 PERCENT... CONTINUING AND SPREADING WEST TO EAST THROUGH THE EVENING BEFORE TAPERING BACK DOWN TO SLIGHT CHANCES OVERNIGHT... AS WE HANG ON TO A WARM MOIST AIR MASS AND AT LEAST MARGINAL INSTABILITY. THICKNESSES SHOULD BE VERY CLOSE TO NORMAL... INDICATIVE OF HIGHS 85-90 WITH SKIES VARYING BETWEEN PARTLY AND MOSTLY CLOUDY. MILD LOWS OF 67-73 WITH INCREASING MID AND HIGH CLOUDS OVERNIGHT AS THE MCV APPROACHES. FOR WEDNESDAY/WEDNESDAY NIGHT: EXPECT A COUPLE OF SHOWERS AND AN ISOLATED STORM OR TWO TO PERSIST INTO WEDNESDAY MORNING GIVEN THE VERY MOIST (PW OF 1.5-1.9 IN.) AND SOMEWHAT UNSTABLE (MLCAPE OF 1000-1500 J/KG) ENVIRONMENT EVEN EARLY IN THE DAY... WITH THE PERSISTENT LEE TROUGH EXTENDING THROUGH CENTRAL NC AND SUBTLE WEAKNESS ALOFT OVER ERN NC. THE WEAK WIND FIELD AND LACK OF DISTINCT SHARP FEATURES TO FOCUS CONVECTION RESULTS IN A FORECAST WITH HIGH CONFIDENCE IN AT LEAST SCATTERED SHOWERS/STORMS BUT LITTLE CONFIDENCE IN THE DETAILS OF EXACTLY WHO IS MOST LIKELY TO SEE RAIN IN CENTRAL NC. PRECIP WATER REMAINS HIGH ANOMALOUSLY HIGH AND THE GFS TRANSLATES THE STEADILY RISING THICKNESSES AND WARMING SURFACE TEMPS TO GREATER INSTABILITY... 2200-3000 J/KG OF MLCAPE ESPECIALLY FROM HIGHWAY 1 EAST. EXPECT ANOTHER ROUND OF GOOD CHANCE POPS FOCUSED ON THE AFTERNOON AND EVENING... AND AS SHOULD BE THE CASE TUESDAY... THE WEAK WIND FIELD WILL LEAD TO MEANDERING AND UNORGANIZED MULTICELL CONVECTION. HIGHS 87-92 AND LOWS 69-73. -GIH && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 250 AM SUNDAY... EVOLUTION TOWARD A MORE AMPLIFIED PATTERN OVER NOAM WILL OCCUR AS WE HEAD INTO THE WEEKEND. A MID LEVEL ANTICYCLONE WILL STRENGTHEN OVER THE FOUR CORNERS REGION IN RESPONSE TO A POWERFUL VORTEX OVER THE NORTHEAST PACIFIC NEAR 47N/140W... WHICH EJECTS SHORTWAVE ENERGY INTO CENTRAL CANADA AND A MID LEVEL JET ACROSS THE DAKOTAS. THE RESULTING FALLING HEIGHTS OVER ONTARIO CULMINATE IN A CLOSED LOW OVER MI OVER THE WEEKEND AND A TREND TOWARD DEEPENING LONGWAVE TROUGHING OVER THE EASTERN HALF OF THE CONUS OVER THE WEEKEND. PRECIP WATER SHOULD REMAIN ABOVE NORMAL THROUGH THE PERIOD WITH SHARPENING OF THE SURFACE TROUGH THROUGH CENTRAL NC AND AN INCREASING WNW MID LEVEL FLOW... FACILITATING GREATER ORGANIZATION OF SHOWERS/STORMS AS WE HEAD INTO THE WEEKEND. GIVEN THIS IMPROVING SHEAR AND LITTLE EXPECTED CHANGE IN THE MOISTURE AND THERMAL PROFILE OVER THE AREA... WILL HOLD ONTO DAILY SCATTERED SHOWERS AND STORMS... MAINLY AFTERNOON AND EVENING. LOW LEVEL THICKNESSES HOLD SLIGHTLY ABOVE NORMAL... SO EXPECT HIGHS IN THE MID 80S TO AROUND 90. WARM LOWS IN THE UPPER 60S TO LOWER 70S. -GIH && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AS OF 700 AM SUNDAY... CEILINGS AND VSBYS VARY WIDELY ACROSS CENTRAL NC...WITH PATCHY LIFR/IFR CONDITIONS BEING REPORTED AMONG WHAT IS OTHERWISE VFR CONDITIONS. STRATUS AFFECTING KFAY AND KRWI WILL LIFT AND EVENTUALLY SCATTER OUT THIS MORNING...REACHING VFR BY 13-14Z. SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE THIS AFTERNOON...WITH THE HIGHEST PROBABILITY FROM THE CENTRAL PIEDMONT TO THE COASTAL PLAIN (KRDU/KFAY/KRWI )...WHERE A WEAK BOUNDARY LINGERS. TONIGHT... WITH HIGH PRESSURE OVER THE WESTERN ATLANTIC AND MOIST SOUTHERLY FLOW ACROSS CENTRAL NC...THE PATTERN WOULD SUGGEST THE POTENTIAL FOR STRATUS TO DEVELOP. FORECAST SOUNDINGS DO NOT INDICATE WIDESPREAD STRATUS...BUT CROSS SECTIONS OF RELATIVE HUMIDITY SUGGEST VERY LOW STRATUS AND/OR FOG WILL BE POSSIBLE. OUTLOOK... WARM AND MOIST SOUTHERLY FLOW AROUND A BERMUDA HIGH WILL BRING UNSETTLED WEATHER FOR MUCH OF THE WEEKEND...WITH SUB-VFR CONDITIONS POSSIBLE EACH MORNING AND SCATTERED SHOWERS/STORMS IN THE AFTERNOON && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...BLS SHORT TERM...HARTFIELD LONG TERM...HARTFIELD AVIATION...BLS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EDT SUN JUN 23 2013 .SYNOPSIS... WEAK LOW PRESSURE OVER EASTERN NORTH CAROLINA WILL GRADUALLY DISSIPATE TODAY. A SURFACE TROUGH WILL LINGER OVER THE PIEDMONT THROUGH MID WEEK... AS A WARM AND MOIST AIR MASS HOLDS OVER THE REGION. && .NEAR TERM /THROUGH MONDAY NIGHT/... AS OF 300 AM SUNDAY... THE WAVE OF LOW PRESSURE THAT MOVED THROUGH EASTERN NC LAST EVENING IS NOW MOVING INTO SOUTH CENTRAL VA...AND THE BULK OF HEAVY RAIN ON ITS EASTERN FLANK IS EXITING THE NORTHERN COASTAL PLAIN. IN ITS WAKE...A WEAK BOUNDARY LINGERS NEAR THE I-95 CORRIDOR...WHERE A FEW SHOWERS AND THUNDER STORMS CONTINUE TO DEVELOP. HRRR SIM REFLECTIVITY SUGGEST PRECIP WILL EVENTUALLY SHIFT NORTHWESTWARD INTO THE PIEDMONT THIS MORNING AS AN UPPER LEVEL LOW OVER THE TN VALLEY LIFTS ALONG THE APPALACHIANS. AS THE DAY WEARS ON...A BROAD SOUTH-SOUTHEASTERLY LOW LEVEL FLOW WILL DOMINATE AS THE BERMUDA HIGH BECOMES ESTABLISHED. MOISTURE CONVERGENCE IN THE VICINITY OF THE WEAK BOUNDARY SHOULD BE THE MAIN FOCUS FOR WHAT WILL OTHERWISE BE SCATTERED SHOWERS AND STORMS IN AN ENVIRONMENT CHARACTERIZED BY PW AROUND 1.8 INCHES AND MLCAPE OF 500-1000 J/KG. HIGHS SHOULD REACH THE MID 80S UNDER PARTLY TO MOSTLY CLOUDY SKIES. TONIGHT... A FEW SHOWERS MAY LINGER INTO THE EVENING HOURS...BUT CONVECTION SHOULD BE MOSTLY DIURNAL IN NATURES. LOW CLOUDS ARE EXPECTED ONCE AGAIN OVERNIGHT AND LOWS WILL FALL ONLY INTO THE UPPER 60S. MONDAY AND MONDAY NIGHT... MOIST SOUTHERLY FLOW WILL CONTINUE ON MONDAY WITH UPPER LEVEL HEIGHTS SLOWLY BUILDING OVER THE WESTERN ATLANTIC AND WEST-SOUTHWESTERLY FLOW ALOFT OVER NC. A WEAK LEE TROUGH WILL BEGIN TO DEVELOP OVER THE PIEDMONT...BUT ITS NOT APPARENT HOW MUCH OF A FOCUS THIS WILL BE FOR AFTERNOON CONVECTION. THERMODYNAMICALLY...THE ATMOSPHERE WILL BE VERY SIMILARLY TO SUNDAY...WITH WEAK LAPSE RATES AND MLCAPE POSSIBLY APPROACHING 1000 J/KG ACROSS THE SOUTH AND EAST. PW WILL REMAIN WELL ABOVE 1.5 INCHES...SUGGESTING SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE. HIGHS WILL BE A COUPLE DEGREES WARMER THAN SUNDAY AS THE UPPER RIDGE BUILDS CLOSER TO THE COAST...85-89. LOWS MONDAY NIGHT IN THE UPPER 60S AND LOWER 70S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 240 AM SUNDAY... FOR TUESDAY/TUESDAY NIGHT: THE MID LEVEL ANTICYCLONE NOW CENTERED OVER THE WRN ATLANTIC WILL HAVE EVOLVED INTO A WEAKER BUT MORE EXPANSIVE RIDGE COVERING MUCH OF THE SOUTHERN HALF OF THE COUNTRY (WEST COAST EXCEPTED) BY TUESDAY... RESULTING IN A WEAK WNW STEERING FLOW OVER NC AND POOR DEEP LAYER SHEAR AS THE WESTERLIES RETREAT WELL TO THE NORTH. MODERATE TO POTENTIALLY HIGH INSTABILITY IS EXPECTED BY AFTERNOON WITH GFS-PROJECTED MLCAPE OF 2000-2800 J/KG PARTICULARLY OVER THE EASTERN AND SOUTHERN PORTIONS OF CENTRAL NC... SUPPORTIVE OF AT LEAST SCATTERED SHOWERS AND STORMS WITH DAYTIME HEATING GIVEN PRECIP WATER VALUES OF 1.6-2.0 INCHES... 150-180 PERCENT OF NORMAL. AN MCV INDICATED BY THE MODELS OVER NEB EARLY MONDAY MORNING IS EXPECTED TO TRACK ACROSS MI/IN/OH BY TUESDAY MORNING BEFORE TRACKING ACROSS THE MID ATLANTIC REGION LATE TUESDAY/TUESDAY NIGHT. THIS ADDED DYNAMIC FORCING FOR ASCENT FROM DPVA (ALBEIT WEAK) COULD RESULT IN BETTER COVERAGE OF CONVECTION IN AND NEAR AND EAST OF THE SURFACE LEE TROUGH LATE AFTERNOON THROUGH THE EVENING. WILL GRADUALLY INCREASE POPS THROUGH THE AFTERNOON TO 40-50 PERCENT... CONTINUING AND SPREADING WEST TO EAST THROUGH THE EVENING BEFORE TAPERING BACK DOWN TO SLIGHT CHANCES OVERNIGHT... AS WE HANG ON TO A WARM MOIST AIR MASS AND AT LEAST MARGINAL INSTABILITY. THICKNESSES SHOULD BE VERY CLOSE TO NORMAL... INDICATIVE OF HIGHS 85-90 WITH SKIES VARYING BETWEEN PARTLY AND MOSTLY CLOUDY. MILD LOWS OF 67-73 WITH INCREASING MID AND HIGH CLOUDS OVERNIGHT AS THE MCV APPROACHES. FOR WEDNESDAY/WEDNESDAY NIGHT: EXPECT A COUPLE OF SHOWERS AND AN ISOLATED STORM OR TWO TO PERSIST INTO WEDNESDAY MORNING GIVEN THE VERY MOIST (PW OF 1.5-1.9 IN.) AND SOMEWHAT UNSTABLE (MLCAPE OF 1000-1500 J/KG) ENVIRONMENT EVEN EARLY IN THE DAY... WITH THE PERSISTENT LEE TROUGH EXTENDING THROUGH CENTRAL NC AND SUBTLE WEAKNESS ALOFT OVER ERN NC. THE WEAK WIND FIELD AND LACK OF DISTINCT SHARP FEATURES TO FOCUS CONVECTION RESULTS IN A FORECAST WITH HIGH CONFIDENCE IN AT LEAST SCATTERED SHOWERS/STORMS BUT LITTLE CONFIDENCE IN THE DETAILS OF EXACTLY WHO IS MOST LIKELY TO SEE RAIN IN CENTRAL NC. PRECIP WATER REMAINS HIGH ANOMALOUSLY HIGH AND THE GFS TRANSLATES THE STEADILY RISING THICKNESSES AND WARMING SURFACE TEMPS TO GREATER INSTABILITY... 2200-3000 J/KG OF MLCAPE ESPECIALLY FROM HIGHWAY 1 EAST. EXPECT ANOTHER ROUND OF GOOD CHANCE POPS FOCUSED ON THE AFTERNOON AND EVENING... AND AS SHOULD BE THE CASE TUESDAY... THE WEAK WIND FIELD WILL LEAD TO MEANDERING AND UNORGANIZED MULTICELL CONVECTION. HIGHS 87-92 AND LOWS 69-73. -GIH && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 250 AM SUNDAY... EVOLUTION TOWARD A MORE AMPLIFIED PATTERN OVER NOAM WILL OCCUR AS WE HEAD INTO THE WEEKEND. A MID LEVEL ANTICYCLONE WILL STRENGTHEN OVER THE FOUR CORNERS REGION IN RESPONSE TO A POWERFUL VORTEX OVER THE NORTHEAST PACIFIC NEAR 47N/140W... WHICH EJECTS SHORTWAVE ENERGY INTO CENTRAL CANADA AND A MID LEVEL JET ACROSS THE DAKOTAS. THE RESULTING FALLING HEIGHTS OVER ONTARIO CULMINATE IN A CLOSED LOW OVER MI OVER THE WEEKEND AND A TREND TOWARD DEEPENING LONGWAVE TROUGHING OVER THE EASTERN HALF OF THE CONUS OVER THE WEEKEND. PRECIP WATER SHOULD REMAIN ABOVE NORMAL THROUGH THE PERIOD WITH SHARPENING OF THE SURFACE TROUGH THROUGH CENTRAL NC AND AN INCREASING WNW MID LEVEL FLOW... FACILITATING GREATER ORGANIZATION OF SHOWERS/STORMS AS WE HEAD INTO THE WEEKEND. GIVEN THIS IMPROVING SHEAR AND LITTLE EXPECTED CHANGE IN THE MOISTURE AND THERMAL PROFILE OVER THE AREA... WILL HOLD ONTO DAILY SCATTERED SHOWERS AND STORMS... MAINLY AFTERNOON AND EVENING. LOW LEVEL THICKNESSES HOLD SLIGHTLY ABOVE NORMAL... SO EXPECT HIGHS IN THE MID 80S TO AROUND 90. WARM LOWS IN THE UPPER 60S TO LOWER 70S. -GIH && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AS OF 150 AM SUNDAY... POOR AVIATION CONDITIONS WILL CONTINUE THIS MORNING...THOUGH CONDITIONS WILL LIKELY VARY FROM LIFR TO MVFR. CONFIDENCE IN HOW QUICKLY LOW CEILINGS WILL DEVELOP REMAINS UNCERTAIN...THOUGH IFR CEILINGS ARE BEGINNING TO SHOW UP AROUND KFAY...AND SHOULD EXPAND NORTHWARD THROUGH 09Z. MEANWHILE...AN UPPER LEVEL LOW MOVING NORTHEAST ALONG THE APPALACHIANS WILL CONTINUE TO SUPPORT A FEW ISOLATED SHOWERS AND STORMS...MAINLY IN THE VICINITY OF A WEAK BOUNDARY EXTENDING FROM KFAY TO KRWI TO KIXA. THE ATMOSPHERE OVER CENTRAL NC WILL CONTINUE TO BE VERY MOIST TODAY...CAUSING CEILINGS TO LIFT SLOWLY AFTER SUNRISE. MVFR CONDITIONS ARE EXPECTED BY 15-16Z...WITH VFR CONDITIONS POTENTIALLY DEVELOPING BY 18Z WITH A LIGHT SOUTHERLY WIND. SCATTERED SHOWERS AND STORMS WILL STILL BE POSSIBLE...THOUGH CONFIDENCE IN LOCATION AND TIMING IS MUCH TOO LOW FOR MENTION IN TAFS. OUTLOOK... WARM AND MOIST SOUTHERLY FLOW AROUND A BERMUDA HIGH WILL BRING UNSETTLED WEATHER FOR MUCH OF THE WEEKEND...WITH SUB-VFR CONDITIONS POSSIBLE EACH MORNING AND SCATTERED SHOWERS/STORMS IN THE AFTERNOON && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...BLS SHORT TERM...HARTFIELD LONG TERM...HARTFIELD AVIATION...BLS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
959 PM CDT MON JUN 24 2013 .UPDATE... ISSUED AT 1000 PM CDT MON JUN 24 2013 CURRENTLY...AN LONE CELL WAS LOCATED OVER NORTHERN MCLEAN COUNTY IN CENTRAL NORTH DAKOTA. LATEST 01Z HRRR CONTINUES TO TRY AND DEVELOP CONVECTION ACROSS THE WEST AND NORTH CENTRAL OVERNIGHT SO CANT COMPLETELY RULE OUT A THUNDERSTORM. THEREFORE WILL CONTINUE TO CARRY A SLIGHT CHANCE OF STORMS TONIGHT. AFTER MIDNIGHT...THERE APPEARS TO BE A BETTER CHANCE OF CONVECTION OVER NORTHWEST NORTH DAKOTA AS CURRENT CONVECTION IN CENTRAL MONTANA TRANSLATES EAST. BULK SHEAR OVER THIS AREA SHOULD INCREASE OVERNIGHT AS A SHORTWAVE OVER THE NORTHWEST U.S. PUSHES INTO THE NORTHERN ROCKIES. THUS HAVE KEPT SOME HIGHER CHANCE POPS OVER THE NORTHWEST INTO THE FAR NORTH CENTRAL TOWARD MORNING. FOG CHANCES APPEAR MINIMAL WITH A STEADY SOUTHEAST FLOW...BUT DO THINK THERE IS A CHANCE OF INCREASING LOW STRATUS TUESDAY MORNING. NO CHANGES TO OVERNIGHT LOWS AS A WARM AND MUGGY NIGHT LOOKS TO BE IN STORE WITH LOWS IN THE LOW TO MID 60S. UPDATE ISSUED AT 709 PM CDT MON JUN 24 2013 UPDATE THIS EVENING DEALS MAINLY WITH EVENING CONVECTION. STILL QUITE UNSTABLE THIS EVENING BUT MODELS SUGGEST WITHOUT SUFFICIENTLY STRONG SHORTWAVE TO INITIATE CONVECTION...THE CAP WILL HOLD. THIS IS EVIDENT WITH THE CONVECTION THAT DEVELOPED JUST NORTH OF BISMARCK LATE THIS AFTERNOON...WHICH CONTINUES TO STRUGGLE TO SURVIVE. HAVE LOWERED POPS TO SLIGHT CHANCE ACROSS MOST OF THE AREA THIS EVENING. KEPT SOME CHANCE POPS IN THE FAR SOUTH IN CASE CONVECTION OVER WESTERN SOUTH DAKOTA MAKES IT UP TO THE BORDER. IF WE COULD GET A CELL TO BREAK THE CAP WE COULD STILL SEE A MARGINALLY SEVERE THUNDERSTORM BUT WITH A WEAK SHEAR PROFILE THIS EVENING...ORGANIZED CONVECTION LOOKS LESS LIKELY THAN IT DID EARLIER IN THE DAY. MODELS ALSO SUGGEST A CONTINUED INFLUX OF LOW LEVEL MOISTURE OVERNIGHT AND DEVELOP LOW STRATUS AFTER MIDNIGHT. THEREFORE BUMPED UP CLOUD COVER LATE TONIGHT...BUT WITH A STEADY SOUTHEAST GRADIENT...THINK THE POTENTIAL FOR FOG DEVELOPMENT IS LIMITED. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 300 PM CDT MON JUN 24 2013 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE STRONG TO SEVERE STORMS NOW THROUGH TUESDAY. LATEST HRRR...RAP...AND BOTH THE 12Z GFS/NAM ARE INDICATING CONVECTION FIRING OFF ANYWHERE FROM NOW THROUGH 21Z OVER THE SOUTHWEST AND SOUTH CENTRAL...SO WILL MAINTAIN HIGHER POPS FOR THESE AREAS. LOTS OF UNCERTAINTY YET WITH THE MID LEVEL CAPPING INVERSION STILL IN PLACE. WIND DISCONTINUITY/WEAK FRONTAL BOUNDARY IS APPARENT WHEN LOOKING AT WIND AND DEWPOINT FIELDS. MOISTURE IS CONVERGING ACROSS THE SOUTHWEST/SOUTH CENTRAL SOUTH OF THIS BOUNDARY WHERE SOUTHEAST WINDS ARE STRONGER. DEWPOINT TEMPS LOWER FARTHER NORTH WITH WEAKER SFC WINDS TO THE NORTH OF THIS BOUNDARY. INCOMING S/WV IMPULSE OVER NORTHWEST SOUTH DAKOTA NEARING SOUTHWEST NORTH DAKOTA WILL BE THE TRIGGER FOR POSSIBLE CONVECTION ONCE AFTERNOON HEATING CONTINUES TO WEAKEN THE CAP. STORMS WILL CONTINUE INTO THE EVENING BEFORE EVENTUALLY WINDING DOWN LATER THIS EVENING AND OVERNIGHT. STRONGER SHORT WAVE MOVES INTO THE DAKOTAS TUESDAY ALONG WITH A COLD FRONTAL PASSAGE TUESDAY AFTERNOON INTO TUESDAY EVENING. STRONG TO SEVERE CONVECTION WILL BE VERY POSSIBLE MANY AREAS...SO WILL MAINTAIN HIGH CHANCES FOR THUNDERSTORMS AND MENTION SEVERE. WILL NEED TO MONITOR LATEST GUIDANCE THIS EVENING AND TONIGHT IN CASE A FLASH FLOOD WATCH BECOMES NECESSARY. RIGHT NOW IT APPEARS STORMS WILL BE FAIRLY PROGRESSIVE. MODELS ARE ALSO PUTTING THE HEAVIEST QPF NORTHWEST AND NORTH CENTRAL...AWAY FROM THE AREAS WHICH RECEIVED THE HEAVIEST RAINFALL THE PAST SEVERAL DAYS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 300 PM CDT MON JUN 24 2013 SHORTWAVE TROUGH AND SURFACE COLD FRONT WILL BE EXITING THE JAMES RIVER VALLEY BY AROUND 06Z WEDNESDAY. EXPECT THREAT OF SEVERE WEATHER TO CONTINUE THROUGH TUESDAY EVENING THEN WANE WEST TO EAST AND END QUICKLY SHORTLY AFTER MIDNIGHT. BEHIND THE DEPARTING WAVE WEDNESDAY A WESTERLY FLOW ENSUES WITH ADDITIONAL SHORTWAVE ENERGY RIDING ACROSS SOUTHERN CANADA. TRENDS WITH THE 12Z RUNS PUSH PREVIOUS CHANCES OF PRECIPITATION FROM NORTH CENTRAL NORTH DAKOTA NOW INTO CANADA RESULTING IN AN OVERALL DRY SCENARIO. HAVE ADJUSTED THE GRIDS TO REFLECT THIS. THEREAFTER...MOSTLY A DRY WEATHER PATTERN AS A FOUR CORNERS HIGH PRESSURE AMPLIFIES NORTH WITH THE RIDGE AXIS EXTENDING WELL INTO SOUTHERN CANADA. HOWEVER A COMPENSATORY NORTHWEST FLOW DOWNSTREAM INTO NORTH DAKOTA WILL DOMINATE THROUGH THE WEEKEND WITH STILL SOME UNCERTAINTY ON HOW MANY SHORTWAVES WILL TOP THE RIDGE AND SLIDE THROUGH NORTHERN AND CENTRAL NORTH DAKOTA. THIS COULD PRODUCE SOME CONVECTION OVER THE WEEKEND...AND ESPECIALLY AT NIGHT WHICH IS A COMMON THEME WITH RIDGE RUNNERS TOPPING THE RIDGE THIS TIME OF YEAR. FAVORED AREAS WOULD BE THE TURTLE MOUNTAINS AND EAST CENTRAL NORTH DAKOTA. MODELS SHOWS A COUPLE OF WAVES EMBEDDED IN THE NORTHWEST FLOW...WITH THE ECMWF SHOWING THESE WAVES FURTHER EAST THAN THE GFS...SO TOO UNCLEAR ON EXACT DETAILS AT THIS TIME. WILL USE THE ALLBLEND WHICH CARRIES A SLIGHT MENTION OVER THE WEEKEND AND WILL NOT MAKE ANY CHANGES AT THIS TIME. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 1000 PM CDT MON JUN 24 2013 VFR CEILINGS THIS EVENING ARE EXPECTED THIS EVENING WITH CONVECTION REMAINING TO OUR SOUTH AND WEST. OVERNIGHT TONIGHT...MODELS SUGGEST AN INCREASE OF 925MB RH AND THE DEVELOPMENT OF LOW STRATUS. THEREFORE BROUGHT A MENTION OF MVFR CEILINGS TO ALL TAF SITES LATE TONIGHT INTO EARLY TUESDAY MORNING. THEN BROUGHT A BETTER CHANCE OF THUNDER TO ALL TAF SITES BY TUESDAY AFTERNOON. SOUTHEAST FLOW TONIGHT ACROSS THE AREA. FLOW WILL SHIFT WEST AT KISN AND KDIK TUESDAY AFTERNOON. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...NH LONG TERM...KS AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
314 PM CDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 313 PM CDT SUN JUN 23 2013 CONVECTION CHANCES CONTINUE TO BE THE PRIMARY FORECAST PROBLEM FOR THE PERIOD. WV LOOP SHOWS THE MAIN SHORTWAVE IS CURRENTLY IN THE PROCESS OF LIFTING THROUGH THE CWA ON ITS WAY INTO CANADA. THE MAIN SFC LOW IS ALREADY IN SOUTHERN MANITOBA...WITH ALL BUT THE FAR NORTHEASTERN CWA SEEING WESTERLY WINDS ON THE SOUTH SIDE OF THE LOW. THE RAIN BAND FROM THIS MORNING HAS LIFTING NORTH INTO CANADA...AND SOME CLEARING HAS BEEN GOING ON ALTHOUGH WITH PRETTY LOW CONVECTIVE TEMPS CU HAS REDEVELOPED RAPIDLY. THERE HAS BEEN A DECREASE IN MOISTURE AS THE WEST WINDS BRING IN DRIER AIR...BUT THERE IS STILL A DECENT AMOUNT OF HUMIDITY AND WITH SOME CLEARING CAPE HAS REACHED AROUND 1000 J/KG ACROSS THE CENTRAL CWA. WHILE THE BEST LIFT WILL BE QUICKLY MOVING OFF TO THE NORTH THIS EVENING...THERE IS ENOUGH INSTABILITY HANGING AROUND THAT CANNOT COMPLETELY RULE OUT THUNDERSTORM REDEVELOPMENT...AND THE RAP AND HRRR SHOW SIGNS OF THIS ALTHOUGH STRENGTH DOES NOT SEEM IMPRESSIVE AT THIS POINT. WILL KEEP SOME 30-60 POPS GOING MAINLY NORTH OF THE HIGHWAY 2 CORRIDOR THROUGH EARLY EVENING BEFORE WE GO DRY AFTER MIDNIGHT. MONDAY SHOULD BE FAIRLY QUIET WITH WEAK UPPER RIDGING BETWEEN SYSTEMS. WINDS WILL SHIFT BACK TO THE SOUTH AS A SFC TROUGH BEGINS TO DEEPEN OVER THE ROCKIES/WESTERN PLAINS. 850MB TEMPS CLIMB BACK UP TOWARDS THE UPPER TEENS C AND WITH PLENTY OF SUN WE SHOULD BE ABLE TO CLIMB INTO THE MID 80S ACROSS MOST OF THE AREA. THE QUIET CONDITIONS WILL BE SHORT LIVED AS MODELS SHOW SOME INDICATION OF A WEAK SHORTWAVE MOVING IN MONDAY NIGHT. THINK THERE COULD BE SOME STORMS MOVING IN FROM THE WEST MONDAY NIGHT...WITH THE MODELS SHOWING SOME ELEVATED INSTABILITY LIFTING INTO THE CWA OVERNIGHT. KEPT SOME POPS AROUND 30 PERCENT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 313 PM CDT SUN JUN 23 2013 THINK THAT THE BETTER CHANCES FOR MORE SIGNIFICANT STORMS WILL BE TUESDAY WHEN A FAIRLY STRONG SHORTWAVE TROUGH MOVES INTO THE DAKOTAS. THE SFC TROUGH AXIS WILL MOVE INTO CENTRAL ND...WITH SOUTHEASTERLY WINDS AHEAD OF IT AND GOOD LOW LEVEL CONVERGENCE. INSTABILITY WILL DEPEND ON EXACTLY ANYTHING OVERNIGHT EVOLVES...BUT THERE IS THE POSSIBILITY OF MORE THAN 2000 J/KG OF CAPE. CONTINUED TO KEEP FAIRLY HIGH POPS FOR THUNDERSTORMS TUESDAY INTO TUESDAY NIGHT...BUT IS A BIT EARLY FOR ANY SEVERE MENTION AT THIS TIME. SOME PRECIP MAY LINGER INTO WEDNESDAY MORNING...BUT OVERALL THERE SHOULD BE A DRYING TREND AS THE UPPER SHORTWAVE PULLS OFF TOWARDS THE GREAT LAKES. TEMPS SHOULD BE FAIRLY SEASONABLE IN THE LOW 80S. WEDNESDAY NIGHT TO SATURDAY NIGHT...MODELS IN GOOD AGREEMENT WITH RETROGRADING AND AMPLIFYING WESTERN CONUS RIDGE AND GREAT LAKES TROUGH AT 500MB. AS A RESULT NW FLOW ACROSS THE NORTHERN PLAINS WILL DEVELOP. THIS WILL MAKE FOR SEASONAL END OF JUNE TEMPERATURES AND NEARLY CLIMO POPS AS THE TIMING OF ANY WEAK SHORT WAVES FEATURE WILL NEED TO COINCIDE WITH PEAK HEATING TO INITIATE ANY DIURNALLY DRIVEN CONVECTION AND OVERALL COVERAGE IS EXPECTED TO BE LOW...THUS THE LOW POPS IN THE EXTENDED. .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1252 PM CDT SUN JUN 23 2013 LOW PRESSURE TRACKING ALMOST DUE NORTH ALONG RED RIVER NEAR HCO WITH TROUGH AND EDGE OF RAIN NOW THRU TVF. EXPECT MVFR CIGS TO CONTINUE TO IMPROVE WITH DRIER AIR MIXING IN ON WESTERLY GUSTS 20 TO 30KTS...SOME ISOLATED SHOWERS THIS AFTERNOON POSSIBLE...WITH VFR CONDITIONS EXPECTED THIS EVENING AND OVERNIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...JR LONG TERM...JR/JK AVIATION...JK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
120 PM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 120 PM CDT SUN JUN 23 2013 MAIN UPDATES EARLY THIS AFTERNOON WERE TO AGAIN MODIFY SKY COVER AND PRECIP/THUNDER CHANCES BASED ON LATEST SATELLITE AND RADAR IMAGERY. THERE REMAINS A CHANCE FOR ISOLATED CONVECTION...SHOWERS OR WEAK THUNDERSTORMS...OVER MUCH OF THE WEST AND CENTRAL THIS AFTERNOON...WITH THE BEST CHANCES NORTH CLOSE TO THE UPPER TROUGH. TEMPERATURE ADJUSTMENTS FROM THE PREVIOUS UPDATE STILL LOOKING GOOD. UPDATE ISSUED AT 1050 AM CDT SUN JUN 23 2013 MAIN UPDATES WERE TO MODIFY SKY COVER AND PRECIP/THUNDER CHANCES BASED ON LATEST SATELLITE AND RADAR IMAGERY. TEMPERATURES WERE TRENDED DOWN A TAD NORTH TO ACCOUNT FOR EXTENSIVE CLOUD COVER...WHICH IS EXPECTED TO PERSIST INTO THE AFTERNOON HOURS LIMITING DAYTIME HEATING. THERE REMAINS A CHANCE FOR ISOLATED CONVECTION...SHOWERS OR WEAK THUNDERSTORMS...OVER MUCH OF THE WEST AND CENTRAL THIS AFTERNOON WITH THE UPPER TROUGH OVER NORTH DAKOTA ALONG WITH SOME INSTABILITY STILL PRESENT. UPDATE ISSUED AT 639 AM CDT SUN JUN 23 2013 THERE WERE MINOR UPDATES TO ACCOUNT FOR THE LATEST SATELLITE AND RADAR IMAGERY TRENDS. CYCLONIC FLOW ALOFT WILL HELP ERODE THE CAP THIS AFTERNOON TO RELEASE WEAK CONVECTIVE INSTABILITY IN THE FORM OF WEAK THUNDERSTORMS...AS INDICATED BY THE LAST SEVERAL RUNS OF THE HRRR MODEL. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY. CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00 UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR 1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT. DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION FOR DETAILS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES. THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT. CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES. THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST STRONGER RIDGING ALOFT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 120 PM CDT SUN JUN 23 2013 WILL MAINTAIN VCSH OR VCTS FOR ALL BUT KDIK THROUGH 00Z EARLY THIS EVENING. SCT-BKN MVFR CU CONTINUES TO DEVELOP AND SPREAD EAST ACROSS THE SOUTHERN TERMINALS AS SKIES CLEAR. BEST CHANCE FOR SHOWERS AND ISOLATED THUNDERSTORMS NORTH CENTRAL AT KMOT NEAR AN UPPER LEVEL LOW PRESSURE SYSTEM. SKIES WILL TREND VFR ALL LOCATIONS BY EARLY THIS EVENING AND PERSIST THROUGH 18Z MONDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...AYD LONG TERM...SCHECK AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1252 PM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 1252 PM CDT SUN JUN 23 2013 ADJUSTED POPS AGAIN FOR CURRENT RADAR TRENDS AS THE MAIN RAIN BAND LIFTS FURTHER NORTH...BUT EXPECT SOME REDEVELOPMENT MAINLY OVER THE NORTHERN CWA AS THE MAIN UPPER SYSTEM COMES OUT AND WITH A BIT OF HEATING...SO KEPT POPS HIGH OVER THE NORTHERN COUNTIES THROUGH THIS EVENING. WILL HAVE TO WATCH HOW MUCH CLEARING WE CAN GET THIS AFTERNOON IN ORDER TO DESTABILIZE AS THE BETTER SHEAR STARTS TO MOVE INTO THE AREA IN ORDER TO GET ANY SEVERE. LOWERED TEMPS A BIT IN SOME AREAS AS SOME LOCATIONS HAVE STAYED CLOUDY AND RAINY AND WILL ONLY RECOVER UP INTO THE UPPER 60S TODAY. UPDATE ISSUED AT 1007 AM CDT SUN JUN 23 2013 MADE SOME ADJUSTMENTS TO POPS FOR CURRENT RADAR TRENDS. THE PRECIP HAS LIFTED OUT OF OUR SOUTHERN COUNTIES AS DRY AIR HAS MOVED IN...AND THAT AREA SHOULD SEE SOME CLEARING LATER ON TODAY. FURTHER NORTH...THERE IS STILL A LOT OF MOISTURE CONVERGENCE AND PRECIP REDEVELOPMENT ALONG THE NORTHERN END OF THE SFC TROUGH AXIS/FRONTAL BOUNDARY FROM DEVILS LAKE TOWARDS MAYVILLE. MORE SHOWERS AND STORMS HAVE DEVELOPED IN THE NORTHEASTERN COUNTIES ALSO AND THINK THAT DEVELOPMENT SHOULD CONTINUE THROUGH MUCH OF THE DAY AS THE MAIN UPPER LOW KICKS SLOWLY OUT. SEVERITY LATER ON WILL DEPEND ON DESTABILIZATION...BUT WILL HAVE TO WATCH THE NORTH FOR ANYTHING GOING UNDER THE MAIN UPPER LOW. UPDATE ISSUED AT 655 AM CDT SUN JUN 23 2013 AN AREA OF SHOWERS AND EMBEDDED THUNDER CONTINUES TO MOVE SLOWLY NORTH THIS MORNING. EXPECT A SLOW WEAKENING TREND FOR A FEW HOURS...BEFORE ACTIVITY INCREASES LATER THIS MORNING AND EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST WITH THIS UPDATE. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE WITH THE CONSISTENT GFS. FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS. FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL COVERAGE NOT CERTAIN. ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON IN THE WEST AHEAD OF THE NEXT SHORTWAVE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN PLACE. FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME. ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN WITH SOME TIME PERIODS. LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1252 PM CDT SUN JUN 23 2013 LOW PRESSURE TRACKING ALMOST DUE NORTH ALONG RED RIVER NEAR HCO WITH TROUGH AND EDGE OF RAIN NOW THRU TVF. EXPECT MVFR CIGS TO CONTINUE TO IMPROVE WITH DRIER AIR MIXING IN ON WESTERLY GUSTS 20 TO 30KTS...SOME ISOLATED SHOWERS THIS AFTERNOON POSSIBLE...WITH VFR CONDITIONS EXPECTED THIS EVENING AND OVERNIGHT. && .HYDROLOGY... ISSUED AT 1252 PM CDT SUN JUN 23 2013 NEW WARNINGS ACROSS THE SOUTHERN VALLEY AT HARWOOD...WEST FARGO... KINDRED...ABERCROMBIE WITH AN INCREASE OF FLOODING TO MODERATE NOW EXPECTED AT WAHPETON AND FARGO AS THE AREA RIVERS RESPOND TO LAST NIGHTS RAINFALL OF ONE TO TWO INCHES ON ALREADY SATURATED SOILS. ALSO...MAPLETON WARNING WAS CANCELLED AS THE RIVER FELL BELOW FLOOD STAGE EARLIER TODAY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...DK LONG TERM...HOPPES/DK AVIATION...JK HYDROLOGY...JK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1050 AM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 1050 AM CDT SUN JUN 23 2013 MAIN UPDATES WERE TO MODIFY SKY COVER AND PRECIP/THUNDER CHANCES BASED ON LATEST SATELLITE AND RADAR IMAGERY. TEMPERATURES WERE TRENDED DOWN A TAD NORTH TO ACCOUNT FOR EXTENSIVE CLOUD COVER...WHICH IS EXPECTED TO PERSIST INTO THE AFTERNOON HOURS LIMITING DAYTIME HEATING. THERE REMAINS A CHANCE FOR ISOLATED CONVECTION...SHOWERS OR WEAK THUNDERSTORMS...OVER MUCH OF THE WEST AND CENTRAL THIS AFTERNOON WITH THE UPPER TROUGH OVER NORTH DAKOTA ALONG WITH SOME INSTABILITY STILL PRESENT. UPDATE ISSUED AT 639 AM CDT SUN JUN 23 2013 THERE WERE MINOR UPDATES TO ACCOUNT FOR THE LATEST SATELLITE AND RADAR IMAGERY TRENDS. CYCLONIC FLOW ALOFT WILL HELP ERODE THE CAP THIS AFTERNOON TO RELEASE WEAK CONVECTIVE INSTABILITY IN THE FORM OF WEAK THUNDERSTORMS...AS INDICATED BY THE LAST SEVERAL RUNS OF THE HRRR MODEL. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY. CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00 UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR 1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT. DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION FOR DETAILS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES. THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT. CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES. THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST STRONGER RIDGING ALOFT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1050 AM CDT SUN JUN 23 2013 WILL MAINTAIN VCSH OR VCTS FOR KISN-KMOT-KBIS-KJMS THROUGH 00Z EARLY THIS EVENING. MVFR CU DEVELOPING ACROSS THE SOUTHERN TERMINALS AS SKIES CLEAR. MVFR ALSO AT KMOT NEAR AN UPPER LEVEL LOW PRESSURE SYSTEM. SKIES WILL TREND VFR ALL LOCATIONS BY EARLY THIS EVENING AND PERSIST THROUGH 12Z MONDAY. && .HYDROLOGY... ISSUED AT 320 AM CDT SUN JUN 23 2013 DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...MUCH LOWER PRECIPITABLE WATER VALUES AND LOWER CONVECTIVE COVERAGE NEGATES THE FLASH FLOOD THREAT. HOWEVER...WILL HAVE TO MONITOR THESE AREAS AGAIN MONDAY AND TUESDAY AS STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE WITH THE RETURN OF DEEP MOISTURE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...AYD LONG TERM...SCHECK AVIATION...NH HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1008 AM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 1007 AM CDT SUN JUN 23 2013 MADE SOME ADJUSTMENTS TO POPS FOR CURRENT RADAR TRENDS. THE PRECIP HAS LIFTED OUT OF OUR SOUTHERN COUNTIES AS DRY AIR HAS MOVED IN...AND THAT AREA SHOULD SEE SOME CLEARING LATER ON TODAY. FURTHER NORTH...THERE IS STILL A LOT OF MOISTURE CONVERGENCE AND PRECIP REDEVELOPMENT ALONG THE NORTHERN END OF THE SFC TROUGH AXIS/FRONTAL BOUNDARY FROM DEVILS LAKE TOWARDS MAYVILLE. MORE SHOWERS AND STORMS HAVE DEVELOPED IN THE NORTHEASTERN COUNTIES ALSO AND THINK THAT DEVELOPMENT SHOULD CONTINUE THROUGH MUCH OF THE DAY AS THE MAIN UPPER LOW KICKS SLOWLY OUT. SEVERITY LATER ON WILL DEPEND ON DESTABILIZATION...BUT WILL HAVE TO WATCH THE NORTH FOR ANYTHING GOING UNDER THE MAIN UPPER LOW. UPDATE ISSUED AT 655 AM CDT SUN JUN 23 2013 AN AREA OF SHOWERS AND EMBEDDED THUNDER CONTINUES TO MOVE SLOWLY NORTH THIS MORNING. EXPECT A SLOW WEAKENING TREND FOR A FEW HOURS...BEFORE ACTIVITY INCREASES LATER THIS MORNING AND EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST WITH THIS UPDATE. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE WITH THE CONSISTENT GFS. FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS. FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL COVERAGE NOT CERTAIN. ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON IN THE WEST AHEAD OF THE NEXT SHORTWAVE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN PLACE. FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME. ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN WITH SOME TIME PERIODS. LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 655 AM CDT SUN JUN 23 2013 AN AREA OF IFR CIGS/VSBY HAS DEVELOP NEAR BJI AND SHOULD SLOWLY IMPROVE THIS MORNING. EXPECT AREAS OF SHOWERS AND A FEW STORMS WITH WINDS SHIFTING TO THE WEST BY LATE MORNING/EARLY AFTERNOON FROM WEST TO EAST BEHIND A COOL FRONT. DRIER AIR WILL ADVECT INTO THE REGION BY LATER THIS AFTERNOON AND PRECIP SHOULD END ALONG WITH VFR CONDITIONS IN ALL AREAS BY LATE AFTERNOON/EARLY EVENING. && .HYDROLOGY... ISSUED AT 345 AM CDT SUN JUN 23 2013 RIVER RISES CONTINUE IN THE SOUTHERN VALLEY AND WAHPETON IS NEARING A CREST NEAR MODERATE FLOOD STAGE. ADDITIONAL HEAVY RAINFALL IS OCCURRING ACROSS PORTIONS OF THE SOUTHERN BASIN THIS MORNING...AND ADDITIONAL LOCAL RISES WILL NEED TO BE MONITORED TODAY ALONG WITH ADDITIONAL HEAVY RAINFALL. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...DK LONG TERM...HOPPES/DK AVIATION...DK HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
653 AM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 655 AM CDT SUN JUN 23 2013 AN AREA OF SHOWERS AND EMBEDDED THUNDER CONTINUES TO MOVE SLOWLY NORTH THIS MORNING. EXPECT A SLOW WEAKENING TREND FOR A FEW HOURS...BEFORE ACTIVITY INCREASES LATER THIS MORNING AND EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST WITH THIS UPDATE. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE WITH THE CONSISTENT GFS. FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS. FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL COVERAGE NOT CERTAIN. ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON IN THE WEST AHEAD OF THE NEXT SHORTWAVE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN PLACE. FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME. ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN WITH SOME TIME PERIODS. LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 655 AM CDT SUN JUN 23 2013 AN AREA OF IFR CIGS/VSBY HAS DEVELOP NEAR BJI AND SHOULD SLOWLY IMPROVE THIS MORNING. EXPECT AREAS OF SHOWERS AND A FEW STORMS WITH WINDS SHIFTING TO THE WEST BY LATE MORNING/EARLY AFTERNOON FROM WEST TO EAST BEHIND A COOL FRONT. DRIER AIR WILL ADVECT INTO THE REGION BY LATER THIS AFTERNOON AND PRECIP SHOULD END ALONG WITH VFR CONDITIONS IN ALL AREAS BY LATE AFTERNOON/EARLY EVENING. && .HYDROLOGY... ISSUED AT 345 AM CDT SUN JUN 23 2013 RIVER RISES CONTINUE IN THE SOUTHERN VALLEY AND WAHPETON IS NEARING A CREST NEAR MODERATE FLOOD STAGE. ADDITIONAL HEAVY RAINFALL IS OCCURRING ACROSS PORTIONS OF THE SOUTHERN BASIN THIS MORNING...AND ADDITIONAL LOCAL RISES WILL NEED TO BE MONITORED TODAY ALONG WITH ADDITIONAL HEAVY RAINFALL. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...DK SHORT TERM...DK LONG TERM...HOPPES/DK AVIATION...DK HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
643 AM CDT SUN JUN 23 2013 .UPDATE... ISSUED AT 639 AM CDT SUN JUN 23 2013 THERE WERE MINOR UPDATES TO ACCOUNT FOR THE LATEST SATELLITE AND RADAR IMAGERY TRENDS. CYCLONIC FLOW ALOFT WILL HELP ERODE THE CAP THIS AFTERNOON TO RELEASE WEAK CONVECTIVE INSTABILITY IN THE FORM OF WEAK THUNDERSTORMS...AS INDICATED BY THE LAST SEVERAL RUNS OF THE HRRR MODEL. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY. CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00 UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR 1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT. DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION FOR DETAILS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES. THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT. CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES. THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST STRONGER RIDGING ALOFT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 639 AM CDT SUN JUN 23 2013 LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS WILL CONTINUE AT KISN AND KMOT THIS MORNING...WITH ACTIVITY BECOMING SCATTERED ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON. GIVEN THE NEAR SATURATED SURFACE OBSERVATIONS THIS MORNING...POCKETS OF MVFR/IFR FOG AND STRATUS ARE POSSIBLE THROUGH 15 UTC. && .HYDROLOGY... ISSUED AT 320 AM CDT SUN JUN 23 2013 DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...MUCH LOWER PRECIPITABLE WATER VALUES AND LOWER CONVECTIVE COVERAGE NEGATES THE FLASH FLOOD THREAT. HOWEVER...WILL HAVE TO MONITOR THESE AREAS AGAIN MONDAY AND TUESDAY AS STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE WITH THE RETURN OF DEEP MOISTURE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SCHECK SHORT TERM...AYD LONG TERM...SCHECK AVIATION...AYD HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
351 AM CDT SUN JUN 23 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE HIGHLIGHT OF THE SHORT TERM ARE CONVECTIVE CHANCES FOR TODAY. CURRENTLY...WIDESPREAD LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS CONTINUES ACROSS MOST OF NORTHERN NORTH DAKOTA IN ASSOCIATION WITH THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET STREAK AHEAD OF THE STRONG SHORTWAVE. AS THIS WAVE CONTINUES TO PROPAGATE TO THE NORTHEAST THROUGH THE MORNING AND AFTERNOON...THE AREA OF MORE WIDESPREAD PRECIPITATION ACROSS NORTHERN NORTH DAKOTA WILL BECOME FOCUSED INTO MANITOBA. HOWEVER...WITH CLEARING SKIES EXPECT SURFACE DESTABILIZATION AND THE DEVELOPMENT OF DIURNALLY DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS AS DEPICTED BY THE 00 UTC 4KM WRF AND THE 06 UTC HRRR AREA WIDE. DO NOT ANTICIPATE WIDESPREAD SEVERE THUNDERSTORMS...HOWEVER...ML CAPE VALUES NEAR 1000 J/KG AND DEEP LAYER SHEAR OF 30-35 KTS SUGGEST THE POTENTIAL FOR MARGINAL SEVERE HAIL WITH THE STRONGER STORMS. CONVECTION IS EXPECTED TO QUICKLY FADE WITH SUNSET...WITH FOG POSSIBLE WITH CLEAR SKIES AND LIGHT WINDS IN A WEAK SURFACE RIDGE AXIS TONIGHT. DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF FAR SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...THE THREAT FOR FLASH FLOODING IS NO LONGER ANTICIPATED. SEE THE HYDROLOGY DISCUSSION FOR DETAILS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 320 AM CDT SUN JUN 23 2013 THE MAIN FOCUS TODAY IS ON THE POTENTIAL FOR STRONG/SEVERE THUNDERSTORMS MONDAY THROUGH TUESDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM IS SCHEDULED TO MOVE ACROSS THE NORTHERN PLAINS TUESDAY AS THE FOUR CORNERS MID/UPPER LEVEL RIDGE AND NORTHEASTERN PACIFIC MID/UPPER LEVEL TROUGH MAINTAIN A BELT OF WESTERLIES ACROSS THE NORTHERN ROCKIES AND DAKOTAS. THE 00 UTC NAM/ECMWF/GFS/GEM GLOBAL ALL AGREE ON GENERAL TIMING OF THE SYSTEM...BUT THERE IS SIGNIFICANT SPREAD ON THE TIMING/LOCATION OF ASSOCIATED CONVECTION. THE UNCERTAINTY ASSOCIATED WITH COMPLEX MESOSCALE INTERACTIONS IS LARGE...SO THERE IS NO EASY WAY TO PICK THE SINGLE MODEL SOLUTION MOST LIKELY TO VERIFY. THUS...FORECASTS USED A CONSENSUS BLEND OF ALL AVAILABLE UTC MODELS/ENSEMBLES. THE STORM PREDICTION CENTER FORECAST FROM THEIR OUTLOOKS CALLS FOR LATE AFTERNOON CONVECTION ALONG THE MT/ND BORDER LOOKS TO FORM AN MCS THAT PROPAGATES INTO THE CENTRAL PLAINS ON MONDAY NIGHT. CONVECTION LOOKS TO REGENERATE OVER CENTRAL NORTH DAKOTA ON TUESDAY FOR ANOTHER ROUND IN CENTRAL AND EASTERN COUNTIES. THEREAFTER...00 UTC MODELS/ENSEMBLES GENERALLY AGREE ON A MORE DIURNAL NATURE FOR THE ISOLATED CONVECTION THAT DOES INITIATE AMIDST STRONGER RIDGING ALOFT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 320 AM CDT SUN JUN 23 2013 LIGHT TO MODERATE RAIN WITH EMBEDDED THUNDERSTORMS WILL CONTINUE AT KISN...KMOT AND KJMS THIS MORNING...WITH ACTIVITY BECOMING SCATTERED ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON. GIVEN THE NEAR SATURATED SURFACE OBSERVATIONS THIS MORNING...POCKETS OF MVFR/IFR FOG AND STRATUS IS POSSIBLE. && .HYDROLOGY... ISSUED AT 320 AM CDT SUN JUN 23 2013 DID CANCEL THE FLASH FLOOD WATCH THAT WAS IN EFFECT FOR THE JAMES RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA. WHILE SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...MUCH LOWER PRECIPITABLE WATER VALUES AND LOWER CONVECTIVE COVERAGE NEGATES THE FLASH FLOOD THREAT. HOWEVER...WILL HAVE TO MONITOR THESE AREAS AGAIN MONDAY AND TUESDAY AS STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE WITH THE RETURN OF DEEP MOISTURE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...AYD LONG TERM...SCHECK AVIATION...AYD HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
348 AM CDT SUN JUN 23 2013 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 THE MAIN CHALLENGE THIS MORNING WILL BE SEVERE STORM THREAT TODAY AND MORE STORMS POSSIBLE MON NIGHT AND TUE. MODELS ARE IN GOOD OVERALL AGREEMENT...AND WILL FOLLOW THE HRRR INITIALLY THEN SIDE WITH THE CONSISTENT GFS. FOR TODAY...EXPECT AN MCS TO BE ONGOING THIS MORNING MOVING FROM SW TO NE. THERE COULD BE LOCALLY HEAVY RAINFALL THIS MORNING IN THE SOUTH...AND THIS AREA IS QUITE SATURATED SO WILL CONTINUE WITH THE FLASH FLOOD WARNING UNTIL 12Z. THERE COULD BE A MORE ORGANIZED SEVERE THREAT BY EARLY AFTERNOON MAINLY IN THE MN COUNTIES ALONG A COLD FRONT...MLCAPE TO AROUND 2000 J/KG AND AMPLE DEEP LAYERED SHEAR. THE MAIN THREATS SHOULD BE LARGE HAIL AND DAMAGING WINDS. FOR TONIGHT...ANY CONVECTION SHOULD QUICKLY MOVE OUT OF THE EASTERN AREAS DURING THE EVENING. DRIER AIR WILL ADVECT INTO THE REGION WITH GENERAL LIGHT WINDS. WILL HAVE TO WATCH FOR PATCHY FOG IN AREAS THAT GET RAIN...BUT FOR NOW WON/T MENTION WITH AREAL COVERAGE NOT CERTAIN. ON MONDAY...EXPECT A DRY AND WARM DAY WITH 850MB TEMPS WARMING TO AROUND +18C. MOISTURE PROFILES WILL BEGIN TO INCREASE BY AFTERNOON IN THE WEST AHEAD OF THE NEXT SHORTWAVE. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 345 AM CDT SUN JUN 23 2013 FOR MONDAY NIGHT AND TUE...THE THREAT FOR SHOWERS AND STORMS WILL ONCE AGAIN INCREASE WITH SHORTWAVE ENERGY MOVING THROUGH GENERAL SW FLOW ALOFT. TIMING STILL REMAINS A QUESTION...BUT THE SEVERE THREAT COULD ALSO INCREASE AT LEAST IN THE WEST ON TUE...AND WILL FEEL LIKE SUMMER WITH TEMPS ABOVE NORMAL AND PLENTY OF MOISTURE IN PLACE. FOR WEDNESDAY THROUGH SATURDAY...A LONG WAVE TROUGH AXIS DEVELOPS OVER THE EASTERN PACIFIC AND THE EASTERN US WHILE A LONG WAVE RIDGE DEVELOPS OVER THE NORTHERN ROCKIES AND INTO THE CANADIAN ROCKIES. PATTERN BECOMES MORE NORTHWEST FLOW ALOFT WITH TIME. ECMWF BEGINS THE PERIOD AS A FASTER SOLUTION THAN THE GFS. THE ECMWF MAINTAINS A CONSISTENT FAST BIAS THROUGH THE PERIOD. THE ECMWF HAS TRENDED WITH FASTER SOLUTIONS OVER THE LAST FEW MODEL RUNS WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS AND WILL SPEED UP PRECIPITATION A BIT FROM TODAYS RUN AND MAY KEEP YESTERDAYS RUN WITH SOME TIME PERIODS. LITTLE CHANGE TO TEMPS THIS PERIOD FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1151 PM CDT SAT JUN 22 2013 BESIDES SOME THUNDER THREAT...MAIN ISSUE NOW IS AREA OF LOW CLOUDS THAT IS MOVING WEST FROM LAKE SUPERIOR INTO THE ERN FCST AREA. HOW FAR THAT WILL GET IS UNKNOWN BUT COULD BE INTO VALLEY LATER TONIGHT SO DID INCLUDE SOME IFR OR LOW END MVFR CIGS DUE TO LIGHT WINDS AND HUMID CONDITIONS. MAIN THREAT FOR RAIN AND STORMS EARLY ON DVL REGION WILL SPREAD INTO THE RRV 10Z-17Z THEN INTO ERN FCST AREA AS FRONT MOVES THROUGH. WINDS WILL TURN WEST BEHIND FRONT MIDDAY TO AFTN WITH GUSTS TO 20+KTS AT DVL-FAR-GFK PSBL. && .HYDROLOGY... ISSUED AT 345 AM CDT SUN JUN 23 2013 RIVER RISES CONTINUE IN THE SOUTHERN VALLEY AND WAHPETON IS NEARING A CREST NEAR MODERATE FLOOD STAGE. ADDITIONAL HEAVY RAINFALL IS OCCURRING ACROSS PORTIONS OF THE SOUTHERN BASIN THIS MORNING...AND ADDITIONAL LOCAL RISES WILL NEED TO BE MONITORED WITH HEAVY RAIN RATES EXPECTED. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR NDZ014-024- 028>030-038-039-049-052-053. MN...FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR MNZ002-003- 022>024-027>032-040. && $$ SHORT TERM...DK LONG TERM...HOPPES/DK AVIATION...RIDDLE HYDROLOGY...DK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
925 PM EDT MON JUN 24 2013 .SYNOPSIS... HIGH PRESSURE OFF THE MIDDLE ATLANTIC COAST WILL CONTINUE TO BRING A SOUTHERLY FLOW OF WARM AND HUMID AIR TO THE AREA THROUGH MID WEEK. A WEAK COLD FRONT WILL STALL TO OUR NORTH ACROSS THE CENTRAL GREAT LAKES TUESDAY. A STRONGER COLD FRONT WILL MOVE ACROSS THE REGION THURSDAY NIGHT INTO FRIDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... BOW ECHO APPEARS TO HAVE WEAKENED SOME DURING THE PAST HOUR AS IT HAS NOW MOVE OVER THE IWX RADAR SITE. WILL SEE IF SPC PUTS OUT ANY NEW WATCHES FURTHER EAST. NOT GETTING ANY HELP FROM THE HRRR AND RUC WHICH HAVE BEEN CLUELESS ALL EVENING. WILL KEEP BROADBRUSH CHANCE POPS FOR THE AREA WITH HIGHER POPS IN WEST WHERE PRECIP MORE IMMINENT. LOWS WILL BE ABOVE GUIDANCE BY A DEGREE OR TWO. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/... NEW DAY...SAME CONCERNS. UPPER FLOW IS NOW FAIRLY ZONAL THANKS TO THE FLATTENING RIDGE. MODELS SHOW AN UPPER TROF DEVELOPING TO OUR WEST BY WEDNESDAY AND THEN MOVING INTO THE REGION THURSDAY. IT THEN GETS TRAPPED IN THE AREA AND THEN REINFORCED FOR THE WEEKEND BUT THAT WILL BE COVERED IN THE SECTION BELOW. FOR TUESDAY MODELS SHOW CONTINUED DEEP MOISTURE ACROSS THE AREA WITH WEAK DISTURBANCES ALOFT MOVING THROUGH THE AREA. EXPECTING MORE COVERAGE THAN TODAY AND WILL HAVE LIKELY TO HIGH CHANCE ACROSS THE NORTHERN TIER OF COUNTIES WITH 30-40% SOUTH. TUESDAY NIGHT INTO WEDNESDAY MODELS SHOW THICKNESS PACKING NORTHWEST TO SOUTHEAST ACROSS THE AREA WITH THE LIKELY GENERATION POINT FOR MCS DEVELOPMENT TO OUR NORTHWEST. CONCERNED THAT WE HAVE CONVECTION MOVE INTO THE AREA TUESDAY NIGHT FROM THE NORTHWEST LASTING INTO WEDNESDAY. WILL HAVE LIKELY POPS NORTHWEST PA AND NERN OHIO AND MID/HIGH CHANCE ELSEWHERE TUESDAY NIGHT AND EARLY WEDNESDAY. LAKE WEDNESDAY WILL HAVE LIKELY POPS MOVING IN FROM THE NORTHWEST WITH APPROACHING UPPER TROF. THURSDAY AN UPPER TROF REMAINS OVER THE AREA WITH DEEP MOISTURE STILL IN PLACE SO WILL CONTINUE LIKELY POPS CENTRAL AND EAST WITH CHANCE POPS WEST. TEMPS WELL ABOVE NORMAL THROUGH MID WEEK AND THEN NEAR NORMAL THURSDAY. && .LONG TERM /FRIDAY THROUGH MONDAY/... UPPER LEVEL TROUGH DIGS INTO THE CENTRAL GREAT LAKES ON FRIDAY THEN AMPLIFIES AS IT SLOWLY PIVOTS EAST OVER THE WEEKEND. THIS WILL CAUSE LOW PRESSURE AT THE SURFACE TO RETROGRADE TO THE WEST WITH A CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS WITHIN THE BROAD CYCLONIC FLOW THROUGH AT LEAST SATURDAY. WILL CARRY A 30-50 PERCENT POP FOR FRIDAY AND SATURDAY WITH A DECREASING TREND FOR SUNDAY AS DRIER AIR GETS WRAPPED INTO THE SYSTEM FROM THE WEST. HIGHS WILL BE NEAR NORMAL ON FRIDAY...AROUND 80...BEFORE DROPPING BACK INTO THE 70S OVER THE WEEKEND. ADJUSTED HIGHS DOWN SEVERAL DEGREES FOR SATURDAY/SUNDAY CLOSER TO RAW MODEL VALUES INSTEAD OF MEX GUIDANCE WHICH IS LIKELY RUNNING TOO HIGH AS IT TRENDS TOWARDS CLIMO IN THE LATER PERIODS. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... THINGS ARE CURRENTLY QUIET AND SHOULD REMAIN THAT WAY THROUGH THE EVENING HOURS. WATCHING THE BOWING LINE OF STORMS OVER NORTHERN INDIANA. HAVE TIMED THIS FEATURE TO REACH KTOL AND KFDY AROUND MIDNIGHT. EXPECTING SOME WEAKENING AS THE STORM APPROACHES. FOR NOW JUST HAVE A MENTION OF THUNDER BUT IF THE LINE HOLDS TOGETHER WILL BEEF UP TAFS TO INCLUDE WIND GUSTS. WILL TIME THE STORMS ACROSS THE AREA DURING THE EARLY MORNING HOURS. SOME HINT OF ADDITIONAL CONVECTION FIRING TOWARD DAYBREAK IN RESPONSE TO A STRONG LOW LEVEL JET. LOT`S OF UNCERTAINTY WITH THIS SCENARIO SO NOT MUCH IN THE TAFS FOR NOW. EXPECT ADDITIONAL THUNDERSTORMS AT THE END OF THE TAF PERIOD. EXPECT VFR CIGS AND VSBYS EXCEPT WITH THE STRONGER STORMS. SOME MVFR FOG POSSIBLE LATE TONIGHT. S TO SW FLOW WILL BECOME GUSTY ON TUESDAY. .OUTLOOK...NON-VFR IN SCATTERED SHOWERS/THUNDERSTORMS AND EARLY MORNING MIST/HAZE THROUGH SATURDAY. && .MARINE... SOUTHWEST FLOW WILL CONTINUE ON THE LAKE AHEAD OF LOW PRESSURE THAT WILL EVENTUALLY APPROACH LATE WEDNESDAY FROM THE PLAINS. SPEEDS WILL INCREASE TO 10-20 KNOTS FOR A PERIOD OF TIME BEFORE SLOWLY VEERING TO THE NORTHWEST THURSDAY AND FRIDAY AS THE LOW SHIFTS TO THE EASTERN GREAT LAKES. TIMING OF THUNDERSTORMS WILL BE DIFFICULT OVER THE NEXT SEVERAL DAYS WITH MULTIPLE ROUNDS OF CONVECTION EXPECTED...ESPECIALLY FROM TUESDAY THROUGH THURSDAY. THUNDERSTORMS HAVE THE POTENTIAL TO BE STRONG GIVEN THE HOT AND HUMID AIRMASS OVER THE REGION. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK/ADAMS SHORT TERM...TK LONG TERM...KEC AVIATION...KUBINA MARINE...KEC
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
755 PM EDT MON JUN 24 2013 .SYNOPSIS... DISTURBANCES EMBEDDED IN ZONAL FLOW WILL CONTINUE TO INTERACT WITH A WARM AND UNSTABLE AIRMASS TO BRING CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE AREA THROUGH MID WEEK. AN APPROACHING COLD FRONT WILL BRING INCREASING CHANCES FOR PRECIPITATION STARTING WEDNESDAY NIGHT. && .NEAR TERM /THROUGH TUESDAY/... ZONAL FLOW HAS DEVELOPED ALOFT ACROSS THE OHIO VALLEY TODAY. A WEAKENING COMPLEX OVERNIGHT ASSOCIATED WITH A DISTURBANCE EMBEDDED IN THE ZONAL FLOW BROUGHT A CONVERGENT LOW LEVEL BOUNDARY TO THE AREA LATE THIS MORNING AND HAS BEEN THE FOCUS FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON. THIS ACTIVITY WILL CONTINUE EASTWARD AND APPEARS THAT IT WILL REACH THE EASTERN EDGE OF THE FORECAST AREA BY THIS EVENING. A LOT OF UNCERTAINTY IS LEFT BEHIND THIS DEPARTING BAND OF CONVECTION...WITH SKIES CLEARING ACROSS THE NORTHWESTERN HALF OF OF THE ILN AREA THIS AFTERNOON. A DECAYING MCV ACROSS NORTHERN INDIANA MAY ACT AS A FOCUS FOR ADDITIONAL CONVECTION ACROSS NORTHERN INDIANA LATE THIS AFTERNOON...AS THE ATMOSPHERE DESTABILIZES IN THE WAKE OF THIS MORNINGS CLOUD COVER. LAPS SOUNDINGS SHOW UP TO 3000 J/KG SFC BASED CAPE JUST TO THE WEST OF OUR NORTHWESTERN ZONES...WITH THE RAP INDICATING THAT DESTABILIZATION WILL CONTINUE INTO THE AFTERNOON AND EARLY EVENING. THE BIG QUESTION BECOMES HOW MUCH FORCING WILL THERE BE FROM THE DECAYING MCV...IF ANY...TO PRODUCE CONVECTION LATE THIS AFTERNOON. WITH THIS UNCERTAINTY IN MIND...AM FORECASTING CHANCE POPS TO MOVE INTO OUR NORTHWESTERN ZONES LATE THIS AFTERNOON AND EVENING...IN CASE THIS CONVECTION DOES INITIATE. ANY CONVECTION THAT DOES DEVELOP WILL LIKELY DIMINISH AROUND SUNSET AS LOW LEVEL FLOW REMAINS WEAK ACROSS OUR AREA...NOT SUPPORTIVE OF NOCTURNAL CONVECTION. SOME CONVECTION WILL PROBABLY REMAIN ONGOING TO OUR NORTH AND NORTHWEST TONIGHT...WHERE LOW TO MID LEVEL FLOW IS STRONGER. TONIGHT WILL BE ANOTHER WARM ONE WITH THE WARM AND HUMID AIRMASS IN PLACE. WENT JUST BELOW GUIDANCE BASED ON BIASES FOR THE PAST COUPLE OF NIGHTS...WITH SOME A WARM BIAS IN THE MODELS BEING NOTICED IN OUR TYPICALLY COOLER VALLEYS. && .SHORT TERM /TUESDAY NIGHT/... ANOTHER DISTURBANCE WILL FOLLOW IN THE WAKE OF TODAYS DISTURBANCE ON TUESDAY. LATEST RAP/NAM/ARW INDICATE THIS DISTURBANCE WILL BE CROSSING SOUTHERN LAKE MICHIGAN EARLY TUESDAY. THE QUESTION IS HOW ARE MODELS HANDLING SOME WARMER AIR ALOFT MOVING INTO THE REGION...AND ITS AFFECT ON A DEVELOPING A CAP ACROSS OUR AREA TUESDAY. MOST MODELS ARE INDICATING A WEAK CAP AROUND 5 KFT AGL BASICALLY SOUTH OF INTERSTATE 70 ON TUESDAY...WHICH WOULD LIMIT AND CONVECTION FROM INITIATING AS THE DISTURBANCE PASSES TO OUR NORTH TUESDAY AFTERNOON. THE NAM/SREF DO NOT BUY INTO THIS SOLUTION...AND HAVE A MUCH WEAKER...AND BREAKABLE CAP IN PLACE. BASED ON THE INHERENT UNCERTAINTIES IN THIS CURRENT CONVECTIVE REGIME...AND THE FACT THAT A GOOD DEAL OF LOW LEVEL MOISTURE IS IN PLACE...CANNOT RULE OUT CONVECTION IN THE SOUTH TUESDAY. WENT WITH CHANCE POPS FOR ALL ZONES WITH 30 POPS IN THE SOUTH AND 40 POPS MAINLY NORTH OF INTERSTATE 70. HIGH TEMPERATURES...BARRING ANY DEBRIS CLOUDS TO START OFF WITH...WILL RISE INTO THE UPPER 80S TO LOWER 90S DURING THE AFTERNOON. UNCERTAINTY INCREASES EVEN FURTHER GOING INTO TUESDAY NIGHT...WITH ADDITIONAL CONVECTION POSSIBLE MAINLY ACROSS THE NORTH AS UPPER LEVEL ENERGY IMPULSES CONTINUE TO MOVE WEST TO EAST IN THE ZONAL FLOW. KEPT POPS IN THE SLIGHT CHANCE TO CHANCE RANGE FOR NOW...IN CASE SOME OF THIS CONVECTION MAKES IT INTO OUR FORECAST AREA DURING THE OVERNIGHT TIME PERIOD. ANOTHER WARM NIGHT WILL RESULT WITH THE CONTINUED WARM AIRMASS. AM ANTICIPATING ENHANCED CLOUD COVER TUESDAY NIGHT WITH SOME CONVECTION TO OUR NORTH...AND POSSIBLE RETURN FLOW CONTINUING INTO THE NIGHT. TEMPERATURES MAY ONLY BOTTOM OUT IN THE LOWER 70S ACROSS MANY OF OUR ZONES...EXCEPT FOR PERHAPS THE RURAL EASTERN ZONES. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THERE ARE SOME MODEL DISCREPANCIES AS TO HOW MUCH IF ANY PCPN WILL BE ONGOING WEDNESDAY MORNING. WILL TREND TOWARD A DRIER FORECAST AT THE ONSET BUT HANG ON TO SOME LOWER POPS JUST TO COVER THE THREAT. ASSUMING THERE ARE NOT TOO MANY LINGERING DEBRIS CLOUDS...WE SHOULD THEN BE ABLE TO DESTABILIZE NICELY THROUGH THE AFTERNOON IF TEMPERATURES CAN PUSH INTO THE UPPER 80S TO NEAR 90. THIS WOULD RESULT IN ML CAPE VALUES IN THE 2000 TO POSSIBLY 3000 J/KG RANGE. THE COMBINATION OF THIS AND SHORT WAVE ENERGY MOVING DOWN ACROSS THE WESTERN GREAT LAKES INTO OUR AREA WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT...SHOULD LEAD TO A DECENT CHANCE OF THUNDERSTORMS PUSHING IN FROM THE NORTHWEST LATE IN THE DAY. WITH INCREASING DYNAMICS ACROSS THE AREA AND FAVORABLE TIMING...THERE IS THE POSSIBILITY OF SOME SEVERE STORMS...ESPECIALLY LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING. PCPN CHANCES WILL THEN CONTINUE INTO THURSDAY AS THE COLD FRONT MOVES THROUGH. HIGHEST POPS FOR THURSDAY WILL BE ACROSS OUR EAST/SOUTHEAST...CLOSER TO THE UPPER LEVEL TROUGH AND WHERE THE COLD FRONT WILL BE LAST TO MOVE THROUGH. BUILDING RIDGE OVER THE WESTERN UNITED STATES WILL CONTINUE TO CARVE OUT A TROUGH ACROSS THE EAST THROUGH THE REMAINDER OF THE LONG TERM PERIOD. THIS WILL KEEP TEMPERATURES FAIRLY SEASONABLE FRIDAY THROUGH MONDAY WITH HIGHS GENERALLY IN THE LOWER 80S. MODELS ARE SHOWING VARIOUS WEAK SHORT WAVES PROGRESSING THROUGH THE TROUGH BUT IT IS TOUGH TO PINPOINT ANY KIND OF TIMING. AS A RESULT...WITH THE UPPER LEVEL TROUGH IN PLACE AND GIVEN THE TIME OF YEAR...THINK THE BEST WAY TO GO IS TO TREND THE POPS DIURNAL BUT KEEP THEM ON THE LOW SIDE THROUGH THE WEEKEND. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... DEEP CONVECTION DEVELOPED IN THE MODERATELY UNSTABLE AIRMASS ALONG AN OUTFLOW WHICH PUSHED EAST OF ILN/S FA BY LATE AFTN. IN THE WAKE OF THIS BOUNDARY...EARLY EVENING CONDITIONS ARE VFR AND VOID OF CONVECTION. COMPLEX OF STORMS OVER NRN IL PUSHING INTO NW INDIANA EXPECTED TO PUSH EAST INTO NRN OHIO OVERNIGHT AND WEAKEN. AT THIS TIME EXPECT THIS CONVECTION TO STAY NORTH OF THE TAF SITES WITH ONLY SOME INCREASE IN HIGH LVL CLOUDS MAINLY ACRS THE NRN TAF SITES. THERE IS CONSIDERABLE UNCERTAINTY ON HOW FAR SOUTH THIS CONVECTION MAKES IT. HAVE KEPT THE TAF SITES DRY OVERNIGHT BUT IF THIS COMPLEX TRACKS A LTL FURTHER SOUTH...THEN KDAY...KCMH AND KLCK WUD HAVE THE BEST CHANCE. LIGHT WIND FLOW AND HIGH LOW LEVEL MSTR WL LEAD TO PATCHY FOG DEVELOPMENT. HAVE MVFR VSBY RESTRICTION AT KILN WITH IFR RESTRICTIONS AT KLUK. IN THE HUMID AIRMASS EXPECT INSTBY TO ONCE AGAIN DEVELOP DURG THE AFTN HOURS. HAVE ADDED A MENTION OF VCSH AT THE NRN TAF SITES WHERE BETTER CHANCE WILL EXIST WITH OUTFLOW FROM TONIGHT CONVECTION LAYING OUT. OUTLOOK...SHOWERS AND THUNDERSTORMS EXPECTED FROM WEDNESDAY AFTERNOON THROUGH THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...LATTO NEAR TERM...LATTO SHORT TERM...LATTO LONG TERM...JGL AVIATION...AR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
748 PM EDT MON JUN 24 2013 .SYNOPSIS... HIGH PRESSURE OFF THE MIDDLE ATLANTIC COAST WILL CONTINUE TO BRING A SOUTHERLY FLOW OF WARM AND HUMID AIR TO THE AREA THROUGH MID WEEK. A WEAK COLD FRONT WILL STALL TO OUR NORTH ACROSS THE CENTRAL GREAT LAKES TUESDAY. A STRONGER COLD FRONT WILL MOVE ACROSS THE REGION THURSDAY NIGHT INTO FRIDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... BAND OF AFTERNOON CONVECTION LOST SUPPORT AND DISSIPATED ABOUT HALFWAY ACROSS THE CWA. AIRMASS REMAINS SOMEWHAT UNSTABLE THE REST OF THE NIGHT. HRRR AND RUC SHOW SOME OF THE CONVECTION OVER LWR MI WITH A VERY WEAK S/W WORKING ESE INTO THE LERI AREA THIS EVENING THEN SOME PART OF THE COMPLEX OVER NW IL MAKING IT AROUND THE LERI AREA AROUND MIDNIGHT OR SO. WILL KEEP CHANCE POPS GOING BUT TRY AND DEPICT SOME BETTER TIMING. LOWS WILL BE ABOVE GUIDANCE BY A DEGREE OR TWO. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/... NEW DAY...SAME CONCERNS. UPPER FLOW IS NOW FAIRLY ZONAL THANKS TO THE FLATTENING RIDGE. MODELS SHOW AN UPPER TROF DEVELOPING TO OUR WEST BY WEDNESDAY AND THEN MOVING INTO THE REGION THURSDAY. IT THEN GETS TRAPPED IN THE AREA AND THEN REINFORCED FOR THE WEEKEND BUT THAT WILL BE COVERED IN THE SECTION BELOW. FOR TUESDAY MODELS SHOW CONTINUED DEEP MOISTURE ACROSS THE AREA WITH WEAK DISTURBANCES ALOFT MOVING THROUGH THE AREA. EXPECTING MORE COVERAGE THAN TODAY AND WILL HAVE LIKELY TO HIGH CHANCE ACROSS THE NORTHERN TIER OF COUNTIES WITH 30-40% SOUTH. TUESDAY NIGHT INTO WEDNESDAY MODELS SHOW THICKNESS PACKING NORTHWEST TO SOUTHEAST ACROSS THE AREA WITH THE LIKELY GENERATION POINT FOR MCS DEVELOPMENT TO OUR NORTHWEST. CONCERNED THAT WE HAVE CONVECTION MOVE INTO THE AREA TUESDAY NIGHT FROM THE NORTHWEST LASTING INTO WEDNESDAY. WILL HAVE LIKELY POPS NORTHWEST PA AND NERN OHIO AND MID/HIGH CHANCE ELSEWHERE TUESDAY NIGHT AND EARLY WEDNESDAY. LAKE WEDNESDAY WILL HAVE LIKELY POPS MOVING IN FROM THE NORTHWEST WITH APPROACHING UPPER TROF. THURSDAY AN UPPER TROF REMAINS OVER THE AREA WITH DEEP MOISTURE STILL IN PLACE SO WILL CONTINUE LIKELY POPS CENTRAL AND EAST WITH CHANCE POPS WEST. TEMPS WELL ABOVE NORMAL THROUGH MID WEEK AND THEN NEAR NORMAL THURSDAY. && .LONG TERM /FRIDAY THROUGH MONDAY/... UPPER LEVEL TROUGH DIGS INTO THE CENTRAL GREAT LAKES ON FRIDAY THEN AMPLIFIES AS IT SLOWLY PIVOTS EAST OVER THE WEEKEND. THIS WILL CAUSE LOW PRESSURE AT THE SURFACE TO RETROGRADE TO THE WEST WITH A CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS WITHIN THE BROAD CYCLONIC FLOW THROUGH AT LEAST SATURDAY. WILL CARRY A 30-50 PERCENT POP FOR FRIDAY AND SATURDAY WITH A DECREASING TREND FOR SUNDAY AS DRIER AIR GETS WRAPPED INTO THE SYSTEM FROM THE WEST. HIGHS WILL BE NEAR NORMAL ON FRIDAY...AROUND 80...BEFORE DROPPING BACK INTO THE 70S OVER THE WEEKEND. ADJUSTED HIGHS DOWN SEVERAL DEGREES FOR SATURDAY/SUNDAY CLOSER TO RAW MODEL VALUES INSTEAD OF MEX GUIDANCE WHICH IS LIKELY RUNNING TOO HIGH AS IT TRENDS TOWARDS CLIMO IN THE LATER PERIODS. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... THINGS ARE CURRENTLY QUIET AND SHOULD REMAIN THAT WAY THROUGH THE EVENING HOURS. WATCHING THE BOWING LINE OF STORMS OVER NORTHERN INDIANA. HAVE TIMED THIS FEATURE TO REACH KTOL AND KFDY AROUND MIDNIGHT. EXPECTING SOME WEAKENING AS THE STORM APPROACHES. FOR NOW JUST HAVE A MENTION OF THUNDER BUT IF THE LINE HOLDS TOGETHER WILL BEEF UP TAFS TO INCLUDE WIND GUSTS. WILL TIME THE STORMS ACROSS THE AREA DURING THE EARLY MORNING HOURS. SOME HINT OF ADDITIONAL CONVECTION FIRING TOWARD DAYBREAK IN RESPONSE TO A STRONG LOW LEVEL JET. LOT`S OF UNCERTAINTY WITH THIS SCENARIO SO NOT MUCH IN THE TAFS FOR NOW. EXPECT ADDITIONAL THUNDERSTORMS AT THE END OF THE TAF PERIOD. EXPECT VFR CIGS AND VSBYS EXCEPT WITH THE STRONGER STORMS. SOME MVFR FOG POSSIBLE LATE TONIGHT. S TO SW FLOW WILL BECOME GUSTY ON TUESDAY. .OUTLOOK...NON-VFR IN SCATTERED SHOWERS/THUNDERSTORMS AND EARLY MORNING MIST/HAZE THROUGH SATURDAY. && .MARINE... SOUTHWEST FLOW WILL CONTINUE ON THE LAKE AHEAD OF LOW PRESSURE THAT WILL EVENTUALLY APPROACH LATE WEDNESDAY FROM THE PLAINS. SPEEDS WILL INCREASE TO 10-20 KNOTS FOR A PERIOD OF TIME BEFORE SLOWLY VEERING TO THE NORTHWEST THURSDAY AND FRIDAY AS THE LOW SHIFTS TO THE EASTERN GREAT LAKES. TIMING OF THUNDERSTORMS WILL BE DIFFICULT OVER THE NEXT SEVERAL DAYS WITH MULTIPLE ROUNDS OF CONVECTION EXPECTED...ESPECIALLY FROM TUESDAY THROUGH THURSDAY. THUNDERSTORMS HAVE THE POTENTIAL TO BE STRONG GIVEN THE HOT AND HUMID AIRMASS OVER THE REGION. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...KEC AVIATION...KUBINA MARINE...KEC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
733 PM EDT MON JUN 24 2013 .SYNOPSIS... AN EARLY SEASON BERMUDA HIGH WILL CONTINUE TO BRING VERY WARM AND HUMID WEATHER TO CENTRAL PENNSYLVANIA THROUGH THE UPCOMING WEEK. EACH DAY WILL BRING A CHANCE OF MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. A DEEP UPPER LEVEL TROUGH WILL BE CARVED OUT FROM THE GREAT LAKES...SOUTH THROUGH THE TENNESSEE VALLEY LATE THIS WEEK INTO EARLY NEXT WEEK. THIS DEVELOPING WEATHER PATTERN WILL LEAD TO SLIGHTLY COOLER TEMPS WITH THE POTENTIAL FOR MORE NUMEROUS SHOWERS AND THUNDERSTORMS AND THE CHANCE FOR LOCALLY HEAVY RAINFALL AMOUNTS. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... HAVE CANCELED THE SVR THUNDERSTORM WATCH FOR THE SERN ZONES AS THE BEST OF THE STORMS HAVE MOVED EAST OF THE AREA. RAP INDICATES CAPE STILL EXCEEDS 1000J...BUT 3 HOUR CHANGES SHOW A STEADY DECREASE...AND THIS SHOULD CONTINUE AS WE LOSE THE SUN AND HEATING. FOR THE REMAINDER OF THE OVERNIGHT I TRIMMED POPS BACK TO JUST SLIGHT CHC FOR THE NEXT FEW HOURS WITH LITTLE OR NO SHOWERS EXPECTED AFTER ABOUT 9-10PM. ANOTHER PARTLY CLOUDY...WARM AND MUGGY NIGHT IS ON TAP IN THE WAKE OF THE DEPARTING CONVECTION. LOW TEMPS WILL BE IN THE LOWER TO MID 60S. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... ADDITIONAL SHOWERS AND STORMS ARE EXPECTED FOR TUESDAY AS MCV`S FROM UPSTREAM CONVECTION SHOULD SLIDE W-E THROUGH THE CWA DURING THE DAYTIME HEAT. IT WILL BE ANOTHER VERY WARM HUMID DAY WITH TEMPS ALMOST A CARBON COPY OF TODAY. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... THE MODELS HAVE FINALLY BEGUN TO CONVERGE AS THE SREF AND GEFS CONTINUES TO SHOW INCREASING PWATS INTERACTING WITH A SERIES OF SHORT WAVES EMBEDDED IN THE WEST TO NWRLY MID- UPPER FLOW. THIS SHOULD BRING SEVERAL ROUNDS OF MAINLY AFTERNOON SHRA/TSRA THROUGHOUT THE WEEK. DUE TO THIS HAVE LEFT CHANCE POPS EACH AFTERNOON. THERE CONTINUES TO BE TIMING AND POSITION VARIANCES...HOWEVER THE PROPAGATION OF THE STORMS THIS WEEK. ALL THE MODELS HARE SHOWING A STRONG FRONT EXTENDING FROM A DEEPENING LOW PRESSURE SYSTEM THAT SHOULD MOVE THROUGH SOUTHERN CANADA ON THURSDAY. THIS WILL BRING A FRONT THROUGH THAT IS CORRESPONDING WITH SIGNIFICANT MOISTURE ALONG WITH A FAST WESTERLY 850 MB FLOW THURSDAY AFTERNOON. BOTH THE EC AND GEFS SHOWS WEST TO SWRLY WINDS AT 850 MB AVERAGING AROUND 25 TO 30 KTS DURING THAT PERIOD WITH A QUASI- STNRY EAST/WEST SFC BOUNDARY MEANDERING NORTHEAST TO SOUTHWEST ACROSS THE REGION. HAVE INCREASED POPS ACCORDINGLY ESPECIALLY GIVEN THE PROBABILITY OF PWATS TO ALLOW FOR SCATTERED TSRA/SHRA. THE SPEED SHEAR PROVIDED BY THE LLJ ON THURSDAY SHOULD ALLOW FOR THE BEST CHANCE FOR SHRA/TSRA. SO HAVE CONTINUED THE GRADUAL INCREASE OF POPS FROM TUESDAY INTO THURSDAY EVENING WHEN THE STRONGEST LARGE SCALE DYNAMICS ENTER INTO THE PICTURE. COOLER WEATHER APPEARS IN STORE FOR NEXT WEEKEND...BUT THE PRESENCE OF COOLER AIR ALOFT AND MID/UPPER TROUGH AXIS COULD MAKE IT SHOWERY IN THE AFTERNOON SATURDAY AND COULD CONTINUE OVER THE WEEKEND. MAX TEMPS MONDAY THROUGH WEDNESDAY WILL BE QUITE CONSISTENT IN THE LOWER TO MID 80S ACROSS THE MTNS...AND AROUND 90F IN THE SUSQ VALLEY. READINGS WILL SLOWLY COOL FOR THURSDAY AND FRIDAY...WITH TEMPS LIKELY RETREATING TO SEVERAL DEG F BELOW NORMAL FOR HIGHS NEXT FRIDAY THROUGH THE UPCOMING WEEKEND. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... THE STRONG AND ORGANIZED THUNDERSTORMS HAVE MOVED TO OUR EAST. A FEW LINGERING VERY ISOLATED THUNDERSTORMS ARE ABOUT BUT SHOULD DIMINISH RAPIDLY BEFORE ABOUT 9 PM. VFR CONDITIONS NEARLY EVERYWHERE. WEAK WINDS AND FLOW ABOUT HIGH PRESSURE...SOME PATCH HAZE AND FOG ABOUT...ESPECIALLY WHERE IT RAINED. MOST AIRPORTS IN OUR REGION RECEIVED NO RAIN TODAY. MOST OF THESE SITES WILL LIKELY STAY VFR TO SOME MVFR IN HAZE/FOG. KLNS WENT TO 3SM THIS AM AND THERE WAS RAIN OVER LANCASTER COUNTY...THEY HAVE THE BEST CHANCE OF GOING TO 3-5SM AFTER ABOUT 2 AM. ANY FOG/HAZE SHOULD BURN OFF FAST...AN HOUR OR SO EITHER SIDE OF 9 AM. THE RING-OF-FIRE EFFECT AND THE DISTURBANCE OVER IL/WI THIS EVENING SUGGESTS WE SHOULD GET SOME THUNDERSTORM ACTIVITY AGAIN IN THE AFTERNOON HOURS. PUT VCTS IN ALL AT THIS TIME EARLIER IN THE WEST THAN IN THE EAST BY 1-3 HOURS. THIS PATTERN OF SOME MVFR OVERNIGHT AND AFTERNOON SCATTERED THUNDER SHOULD CONTINUE UNTIL A WAVE APPROACHES FRI/SAT BRINGING MORE ORGANIZED RAIN/SHOWER POTENTIAL. THEN COOLER WEATHER. OUTLOOK... TUE-FRI...AREAS OF AM MVFR FOG/HAZE POSS. SCATTERED MAINLY AFTN THUNDERSTORMS. PERHAPS MORE ORGANIZED SHOWERS/TSRA FRIDAY/SATURDAY. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...CERU/STEINBUGL AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
727 PM EDT MON JUN 24 2013 .SYNOPSIS... AN EARLY SEASON BERMUDA HIGH WILL CONTINUE TO BRING VERY WARM AND HUMID WEATHER TO CENTRAL PENNSYLVANIA THROUGH THE UPCOMING WEEK. EACH DAY WILL BRING A CHANCE OF MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. A DEEP UPPER LEVEL TROUGH WILL BE CARVED OUT FROM THE GREAT LAKES...SOUTH THROUGH THE TENNESSEE VALLEY LATE THIS WEEK INTO EARLY NEXT WEEK. THIS DEVELOPING WEATHER PATTERN WILL LEAD TO SLIGHTLY COOLER TEMPS WITH THE POTENTIAL FOR MORE NUMEROUS SHOWERS AND THUNDERSTORMS AND THE CHANCE FOR LOCALLY HEAVY RAINFALL AMOUNTS. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... HAVE CANCELED THE SVR THUNDERSTORM WATCH FOR THE SERN ZONES AS THE BEST OF THE STORMS HAVE MOVED EAST OF THE AREA. RAP INDICATES CAPE STILL EXCEEDS 1000J...BUT 3 HOUR CHANGES SHOW A STEADY DECREASE...AND THIS SHOULD CONTINUE AS WE LOSE THE SUN AND HEATING. FOR THE REMAINDER OF THE OVERNIGHT I TRIMMED POPS BACK TO JUST SLIGHT CHC FOR THE NEXT FEW HOURS WITH LITTLE OR NO SHOWERS EXPECTED AFTER ABOUT 9-10PM. ANOTHER PARTLY CLOUDY...WARM AND MUGGY NIGHT IS ON TAP IN THE WAKE OF THE DEPARTING CONVECTION. LOW TEMPS WILL BE IN THE LOWER TO MID 60S. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... ADDITIONAL SHOWERS AND STORMS ARE EXPECTED FOR TUESDAY AS MCV`S FROM UPSTREAM CONVECTION SHOULD SLIDE W-E THROUGH THE CWA DURING THE DAYTIME HEAT. IT WILL BE ANOTHER VERY WARM HUMID DAY WITH TEMPS ALMOST A CARBON COPY OF TODAY. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... THE MODELS HAVE FINALLY BEGUN TO CONVERGE AS THE SREF AND GEFS CONTINUES TO SHOW INCREASING PWATS INTERACTING WITH A SERIES OF SHORT WAVES EMBEDDED IN THE WEST TO NWRLY MID- UPPER FLOW. THIS SHOULD BRING SEVERAL ROUNDS OF MAINLY AFTERNOON SHRA/TSRA THROUGHOUT THE WEEK. DUE TO THIS HAVE LEFT CHANCE POPS EACH AFTERNOON. THERE CONTINUES TO BE TIMING AND POSITION VARIANCES...HOWEVER THE PROPAGATION OF THE STORMS THIS WEEK. ALL THE MODELS HARE SHOWING A STRONG FRONT EXTENDING FROM A DEEPENING LOW PRESSURE SYSTEM THAT SHOULD MOVE THROUGH SOUTHERN CANADA ON THURSDAY. THIS WILL BRING A FRONT THROUGH THAT IS CORRESPONDING WITH SIGNIFICANT MOISTURE ALONG WITH A FAST WESTERLY 850 MB FLOW THURSDAY AFTERNOON. BOTH THE EC AND GEFS SHOWS WEST TO SWRLY WINDS AT 850 MB AVERAGING AROUND 25 TO 30 KTS DURING THAT PERIOD WITH A QUASI- STNRY EAST/WEST SFC BOUNDARY MEANDERING NORTHEAST TO SOUTHWEST ACROSS THE REGION. HAVE INCREASED POPS ACCORDINGLY ESPECIALLY GIVEN THE PROBABILITY OF PWATS TO ALLOW FOR SCATTERED TSRA/SHRA. THE SPEED SHEAR PROVIDED BY THE LLJ ON THURSDAY SHOULD ALLOW FOR THE BEST CHANCE FOR SHRA/TSRA. SO HAVE CONTINUED THE GRADUAL INCREASE OF POPS FROM TUESDAY INTO THURSDAY EVENING WHEN THE STRONGEST LARGE SCALE DYNAMICS ENTER INTO THE PICTURE. COOLER WEATHER APPEARS IN STORE FOR NEXT WEEKEND...BUT THE PRESENCE OF COOLER AIR ALOFT AND MID/UPPER TROUGH AXIS COULD MAKE IT SHOWERY IN THE AFTERNOON SATURDAY AND COULD CONTINUE OVER THE WEEKEND. MAX TEMPS MONDAY THROUGH WEDNESDAY WILL BE QUITE CONSISTENT IN THE LOWER TO MID 80S ACROSS THE MTNS...AND AROUND 90F IN THE SUSQ VALLEY. READINGS WILL SLOWLY COOL FOR THURSDAY AND FRIDAY...WITH TEMPS LIKELY RETREATING TO SEVERAL DEG F BELOW NORMAL FOR HIGHS NEXT FRIDAY THROUGH THE UPCOMING WEEKEND. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... MOST OF THE STRONG TO SEVERE THUNDERSTORMS HAVE MOVED TO OUR EAST. THERE STILL WERE STORMS IN CENTRAL PA. SEVERAL NEAR KLNS AND A THUNDERSTORM WILL LIKELY IMPACT THE KSEG AREA BETWEEN 530 AND 6 PM THIS EVENING. STILL SOME STORMS EAST OF KIPT. CANNOT RULE OUT A FEW POP-UP STORMS NEAR KAOO AND NEAR AND EAST OF KBFD OVER THE NEXT 1-2 HOURS. EXPECT THE THUNDERSTORM ACTIVITY TO DIMINISH BETWEEN 7 AND 9 PM. VFR ALL AREAS OUTSIDE OF THESE VERY ISOLATED STORMS. THEN VFR THROUGH ABOUT MIDNIGHT. AFTER MIDNIGHT PATCHY AREAS OF HAZE AND FOG WILL DEVELOP. MVFR/VFR SHOULD BE THE MORE GENERAL RULE OVERNIGHT. ANY MVFR WILL BURN OFF FAST TUESDAY MORNING. THEN WE CAN START THE SHOWER AND THUNDERSTORM ISSUE UP AGAIN ABOUT NOON. PREVIOUS FOR EXTENDED LOOKS GOOD STILL: THIS PATTERN OF HAZE/FOG AT NIGHT AND AFTERNOON POP-UP SHOWERS/TSRA SHOULD CONTINUE THROUGH A GOOD PART OF THE WEEK. AT THIS TIME BEST CHANCE OF ORGANIZED SHOWERS/THUNDER COULD BE FRIDAY IF THE CURRENT FORECAST FRONT AND TROUGH ARRIVE AS ADVERTISED. OUTLOOK... TUE-FRI...AREAS OF AM MVFR FOG/HAZE POSS. SCATTERED MAINLY AFTN THUNDERSTORMS. PERHAPS MORE ORGANIZED SHOWERS/TSRA FRIDAY/SATURDAY. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...CERU/STEINBUGL AVIATION...GRUMM/LAMBERT
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1043 PM CDT MON JUN 24 2013 .UPDATE... ISSUED AT 1003 PM CDT MON JUN 24 2013 EVENING RAOBS REALLY WARM ALOFT TO THE SOUTHWEST...WITH COOLER READINGS TO THE NORTHEAST REFLECTED IN THE EARLIER LINGERING SHOWERS AND THUNDERSTORMS OVER THE FAR EASTERN CWA. LOOKS MUCH AS IF A GOOD PORTION OF THE LATER EVENING WILL BE QUIET...AS ACTIVITY OUT WEST STRUGGLES A BIT PUSHING INTO THE WARM/DRY LAYER ALOFT TO THE EAST. LIKELY TO SEE DEVELOPMENT OF A WARM ADVECTION WING ONCE AGAIN WHICH SHOULD FAVOR THE EASTERN HALF OF THE CWA AS IT EVOLVES WITH STRENGTHENING LOW LEVEL JET TONIGHT AS WESTERN PLAINS WAVE PUSHES EASTWARD. VERY LIKELY THAT THERE COULD END UP AN AREA BETWEEN THE DWINDLING WESTERN ACTION AND THAT LIFTING/DEVELOPING NORTHEAST...AS SEVERAL OF THE LATER AFTERNOON HRRR RUNS HAVE SUGGESTED. HOWEVER...LAST TWO RUNS OF 00Z AND 01Z HAVE BEEN COMPLETE OPPOSITES WITH ONE EXTREMELY ACTIVE OVER A LARGE AREA... AND ANOTHER WITH VERY LITTLE ACTIVITY. MADE A FEW CHANGES TO DECREASE POPS IN PART OF THE AREA BETWEEN WESTERN AND EASTERN AREAS OF PRECIP...AND DID INCREASE POPS SOMEWHAT EARLY TUESDAY IN THE FAR SOUTHEAST AS WILL BE LAST AREA OF LINGERING WAVE. OTHER INTERESTING NOTE...A WEAK CONVECTIVE HEAT BURST THIS EVENING AT PHILIP...AND IF WE COULD GET A LITTLE BETTER ORGANIZED ACTIVITY MOVING INTO THE AREA...THEN DISSIPATE...WOULD CERTAINLY BE A SET UP FAVORABLE TO GET SUCH AN EVENT IN OUR CWA GIVEN THE UPSTREAM THERMODYNAMIC PROFILE FOR KLBF. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 414 PM CDT MON JUN 24 2013 THE VANISHING OF NIGHTTIME AND EARLY MORNING SHOWERS AND STORMS HAS TAKEN PLACE PRETTY MUCH AS EXPECTED...ALTHOUGH WILL KEEP AN EYE ON THE POTENTIAL FOR ISOLATED SHOWERS OR STORMS EAST OF I 29 LATE THIS AFTERNOON. THE SLOW START TO CLEARING AND HEATING PRETTY MUCH GUARANTEES A SLOW START TO STORMS THIS EVENING. THE GFS...NAM... AND GEM ALL SHOW A SHORT WAVE PASSING OVER THE AREA TONIGHT... CURRENTLY NOTED ENTERING INTO THE WESTERN PLAINS. THE FOCUS HAS SHIFTED TO AN EXPECTATION OF OVERNIGHT ACTIVITY STILL LINGERING AT DAYBREAK...INSTEAD OF EVENING SHOWERS AND STORMS DECREASING STEADILY AFTER MIDNIGHT AS WE HAD IN THE MORNING FORECAST. PATH AND TIMING WILL DEPEND ON WHERE AND HOW EXTENSIVELY STORMS DEVELOP WEST OF OUR AREA EARLY THIS EVENING. MUCH OF THE GUIDANCE SUGGESTS A TRACK MORE TO THE NORTH...BUT WITH A SLIGHT RISK OF SEVERE STORMS EXTENDING DOWN THROUGH THE MISSOURI RIVER VALLEY. THIS WOULD AT LEAST REFLECT A HIGHER CONDITIONAL SEVERE RISK SOUTH AND THIS SEEMS REASONABLE. POPS WILL BE FAIRLY GENERAL OVER THE AREA TONIGHT WITH THE HIGHEST POPS MIGRATING SLOWLY FROM WEST TO EAST. REFINEMENT WILL BE MADE AS ACTIVITY DEVELOPS AND THE PATH OF STORMS BECOMES EVIDENT. HIGHEST QPF POTENTIAL LOOKS TO BE IN OUR NORTHERN AND EASTERN ZONES AS THE PRECIPITATION RIDES OVER A BIT OF CAPPING POTENTIAL. FOR THE TIME BEING WILL GO WITH THE GUIDANCE IDEA OF MODEST AMOUNTS...THAT IS LESS THAN AN INCH...BUT THIS OF COURSE WILL LIKELY TO TURN OUT WITH DRASTIC SHORT RANGE VARIATIONS EVEN IF THE GENERAL RAINFALL OUTLOOK IS GOOD. LOW TEMPERATURES LOOK TO BE NEAR GUIDANCE VALUES WHICH IS VERY SLIGHTLY COOLER THAN WHAT WE HAVE BEEN GOING FOR...MAINLY MID TO UPPER 60S. LINGERING SHOWERS AND STORMS SHOULD DECREASE EARLY TUESDAY MORNING AND WARMING SHOULD HELP KEEP STORMS AWAY FOR MOST OF TUESDAY. HOWEVER SOME CHANCE WILL BE RESTORED MAINLY NORTH BY EARLY AFTERNOON AS BOUNDARIES PROVIDED BY NIGHTTIME STORMS MAY LINGER FOR A FOCUS...AND LATE DAY STORMS MAY DEVELOP MAINLY NORTHEAST FOR THE SAME REASON. FURTHER SOUTH...IT WILL BE HARD TO GET ANYTHING GOING MOST OF THE DAY DUE TO THE WARMING AND CAPPING. HOWEVER...THERE WILL BE A DISTINCT WAVE APPROACHING WHICH COULD TURN THAT AROUND...AGAIN THOUGH NOT UNTIL FAIRLY LATE IN THE DAY. TEMPERATURES SHOULD BE A LITTLE WARMER THAN TODAY THOUGH ANY 90 PLUS HIGHS SHOULD BE CONFINED TO SOUTH OF INTERSTATE 90. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 414 PM CDT MON JUN 24 2013 ALL MODELS ARE IN GOOD AGREEMENT IN BRINGING THE AFOREMENTIONED AND FAIRLY VIGOROUS SHORT WAVE THROUGH OUR NORTHERN AND SOME OF OUR EASTERN ZONES MAINLY TUESDAY EVENING. HAVE A HIGH DEGREE OF CONFIDENCE THAT SOME RAINFALL WILL OCCUR...JUST LIKELY NOT EVERYWHERE THROUGHOUT OUR NORTH AND EAST...THEREFORE PLACED COVERAGE POPS IN THOSE AREAS TUESDAY NIGHT INSTEAD OF UNCERTAINTY. THE HIGHEST ML CAPES EXIST TO THE WEST OF THE PRECIP AREAS. BUT STILL...ML CAPES OF OVER 1000 J/KG ARE NOTED IN OUR NORTH AND EAST COUPLED WITH 0 TO 3KM BULK SHEAR OF 25 TO 35 KNOTS EARLY IN THE EVENING. WITH 700MB TEMPERATURES CLOSE TO ONLY AROUND +10C...BELIEVE A LOW END SEVERE THREAT EXISTS IN OUR NORTH AND EAST EARLY IN THE EVENING...WITH HAIL AROUND THE SIZE OF QUARTERS OR HALF DOLLARS AND WIND GUSTS AROUND 60 MPH. THIS ACTIVITY SHOULD RAPIDLY MOVE EASTWARD THOUGH. OTHERWISE AFTER TUESDAY NIGHT...OUR WELL ADVERTISED UPPER RIDGING BEGINS TO TAKE HOLD WHICH WILL BEGIN TO QUIET DOWN OUR WEATHER. A COLD FRONT...MAINLY IN NAME ONLY...WILL SHIFT OUR WINDS TO THE NORTHWEST LATE TUESDAY NIGHT AND LASTING THROUGH THE DAY ON WEDNESDAY. WITH MIXING POTENTIAL AND NOT ANY BONAFIDE COOL AIR BEHIND THE WAVE...DO NOT EXPECT A LOT OF COOLING ON WEDNESDAY WITH WIDESPREAD 80S STILL PREVAILING. DEW POINTS WILL BE DOWN THOUGH AT LEAST WEST OF I 29. WITH LIGHT WINDS AND RELATIVELY DRIER AIR OOZING DOWN THROUGH THE AREA WEDNESDAY NIGHT...WE CAN EXPECT LOWS DOWN INTO THE LOWER 60S FOR MOST LOCATIONS. ON THURSDAY AS THE UPPER RIDGE BEGINS TO NUDGE WESTWARD...THERE IS SOME MODEL AGREEMENT IN BRINGING A WAVE DOWN OUR AREA FROM NORTHWEST TO SOUTHEAST WHICH COULD SPAWN SOME ACCAS SHOWERS OR THUNDERSTORMS. THE WAVE IS BASED AT 700MB...AND THE SOUNDINGS AND HUMIDITY TIME SECTIONS DO SHOW A PRETTY GOOD INCREASE IN MID LEVEL MOISTURE. THE 12Z NAM BLANKETS JUST ABOUT OUR ENTIRE FORECAST AREA WITH LIGHT PRECIPITATION. HOWEVER I CHOSE TO KEEP THE SMALL POPS IN OUR MISSOURI RIVER VALLEY ZONES WHERE THE STRONGEST PORTION OF THE 700MB DEFORMATION TAKES PLACE PROVIDING MID LEVEL CONVERGENCE... AND THIS IS JUXTAPOSED WITH A 700MB THERMAL GRADIENT GOING FROM +9C TO +12C IN THAT AREA. THURSDAYS HIGHS WILL STILL BE KIND OF WARM...WITH MID 80S TO AROUND 90 COMMON. THEN THINGS BEGIN TO CHANGE. BOTH THE ECMWF AND GFS ARE IN EXCELLENT AGREEMENT IN CONTINUING TO PUSH THE UPPER RIDGE WESTWARD...WHILE DEEPENING AN UPPER LOW OVER THE EASTERN UNITED STATES.. THIS CREATES A HIGH AMPLITUDE PATTERN WITH THE LATEST MODEL RUNS SHOWING A LOT OF SHORT WAVE ENERGY MOVING SOUTHWARD DOWN THE MISSISSIPPI VALLEY REGION. COOL HIGH PRESSURE BEGINS TO FILL IN DOWN FROM THE NORTHWEST AND THUS REALLY COOLS OFF OUR 850MB TEMPERATURES IN A BIG WAY. BY SUNDAY...THE ECMWF HAS +10C TO +14C AT 850MB IN OUR FORECAST AREA...WITH THE GFS EVEN COOLER. THEREFORE A COOLING TREND IS IN ORDER. FURTHERMORE...WITH THE SHORT WAVE ENERGY INTERACTING WITH COOL MID LEVEL TEMPERATURES... WOULD NOT RULE OUT SOME INSTABILITY SHOWERS IN OUR EASTERN ZONES THIS WEEKEND. THE POPS ON DAY 7 MONDAY ARE WISHY WASHY AND WERE MAINLY BASED ON A MORE SIGNIFICANT SHORT WAVE DIVING DOWN THE NORTHWEST FLOW ALOFT ON SOME PREVIOUS VERSION OF THE ECMWF. THE NEW 12Z ECMWF HAS BACKED OFF ON THIS IDEA WITH THE LARGE UPPER TROUGH CONTINUING JUST TO OUR EAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1035 PM CDT MON JUN 24 2013 CONVECTIVE CHANCES RATHER DIFFICULT TO PIN DOWN THIS EVENING...WITH NEW MODEL RUN INCONSISTENCIES...BUT THE BETTER CHANCES LOOK TO BE ACROSS NORTHWESTERN IOWA INTO SOUTHWESTERN MINNESOTA LATER TONIGHT INTO TUESDAY MORNING. AFTER MORNING CONVECTION EXITS THE AREA...WILL SEE A BREAK BEFORE POSSIBLE REDEVELOPMENT NORTH OF INTERSTATE 90 LATER ON TUESDAY AFTERNOON. WHILE VFR CONDITIONS ARE EXPECTED TO DOMINATE THROUGH THE TAF PERIOD...BRIEF REDUCED CONDITIONS WILL BE POSSIBLE IN AREAS EFFECTED BY SCATTERED CONVECTION. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ UPDATE...CHAPMAN SHORT TERM...MJF LONG TERM...MJF AVIATION...JM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1005 PM CDT MON JUN 24 2013 .UPDATE... ISSUED AT 1003 PM CDT MON JUN 24 2013 EVENING RAOBS REALLY WARM ALOFT TO THE SOUTHWEST...WITH COOLER READINGS TO THE NORTHEAST REFLECTED IN THE EARLIER LINGERING SHOWERS AND THUNDERSTORMS OVER THE FAR EASTERN CWA. LOOKS MUCH AS IF A GOOD PORTION OF THE LATER EVENING WILL BE QUIET...AS ACTIVITY OUT WEST STRUGGLES A BIT PUSHING INTO THE WARM/DRY LAYER ALOFT TO THE EAST. LIKELY TO SEE DEVELOPMENT OF A WARM ADVECTION WING ONCE AGAIN WHICH SHOULD FAVOR THE EASTERN HALF OF THE CWA AS IT EVOLVES WITH STRENGTHENING LOW LEVEL JET TONIGHT AS WESTERN PLAINS WAVE PUSHES EASTWARD. VERY LIKELY THAT THERE COULD END UP AN AREA BETWEEN THE DWINDLING WESTERN ACTION AND THAT LIFTING/DEVELOPING NORTHEAST...AS SEVERAL OF THE LATER AFTERNOON HRRR RUNS HAVE SUGGESTED. HOWEVER...LAST TWO RUNS OF 00Z AND 01Z HAVE BEEN COMPLETE OPPOSITES WITH ONE EXTREMELY ACTIVE OVER A LARGE AREA... AND ANOTHER WITH VERY LITTLE ACTIVITY. MADE A FEW CHANGES TO DECREASE POPS IN PART OF THE AREA BETWEEN WESTERN AND EASTERN AREAS OF PRECIP...AND DID INCREASE POPS SOMEWHAT EARLY TUESDAY IN THE FAR SOUTHEAST AS WILL BE LAST AREA OF LINGERING WAVE. OTHER INTERESTING NOTE...A WEAK CONVECTIVE HEAT BURST THIS EVENING AT PHILIP...AND IF WE COULD GET A LITTLE BETTER ORGANIZED ACTIVITY MOVING INTO THE AREA...THEN DISSIPATE...WOULD CERTAINLY BE A SET UP FAVORABLE TO GET SUCH AN EVENT IN OUR CWA GIVEN THE UPSTREAM THERMODYNAMIC PROFILE FOR KLBF. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 414 PM CDT MON JUN 24 2013 THE VANISHING OF NIGHTTIME AND EARLY MORNING SHOWERS AND STORMS HAS TAKEN PLACE PRETTY MUCH AS EXPECTED...ALTHOUGH WILL KEEP AN EYE ON THE POTENTIAL FOR ISOLATED SHOWERS OR STORMS EAST OF I 29 LATE THIS AFTERNOON. THE SLOW START TO CLEARING AND HEATING PRETTY MUCH GUARANTEES A SLOW START TO STORMS THIS EVENING. THE GFS...NAM... AND GEM ALL SHOW A SHORT WAVE PASSING OVER THE AREA TONIGHT... CURRENTLY NOTED ENTERING INTO THE WESTERN PLAINS. THE FOCUS HAS SHIFTED TO AN EXPECTATION OF OVERNIGHT ACTIVITY STILL LINGERING AT DAYBREAK...INSTEAD OF EVENING SHOWERS AND STORMS DECREASING STEADILY AFTER MIDNIGHT AS WE HAD IN THE MORNING FORECAST. PATH AND TIMING WILL DEPEND ON WHERE AND HOW EXTENSIVELY STORMS DEVELOP WEST OF OUR AREA EARLY THIS EVENING. MUCH OF THE GUIDANCE SUGGESTS A TRACK MORE TO THE NORTH...BUT WITH A SLIGHT RISK OF SEVERE STORMS EXTENDING DOWN THROUGH THE MISSOURI RIVER VALLEY. THIS WOULD AT LEAST REFLECT A HIGHER CONDITIONAL SEVERE RISK SOUTH AND THIS SEEMS REASONABLE. POPS WILL BE FAIRLY GENERAL OVER THE AREA TONIGHT WITH THE HIGHEST POPS MIGRATING SLOWLY FROM WEST TO EAST. REFINEMENT WILL BE MADE AS ACTIVITY DEVELOPS AND THE PATH OF STORMS BECOMES EVIDENT. HIGHEST QPF POTENTIAL LOOKS TO BE IN OUR NORTHERN AND EASTERN ZONES AS THE PRECIPITATION RIDES OVER A BIT OF CAPPING POTENTIAL. FOR THE TIME BEING WILL GO WITH THE GUIDANCE IDEA OF MODEST AMOUNTS...THAT IS LESS THAN AN INCH...BUT THIS OF COURSE WILL LIKELY TO TURN OUT WITH DRASTIC SHORT RANGE VARIATIONS EVEN IF THE GENERAL RAINFALL OUTLOOK IS GOOD. LOW TEMPERATURES LOOK TO BE NEAR GUIDANCE VALUES WHICH IS VERY SLIGHTLY COOLER THAN WHAT WE HAVE BEEN GOING FOR...MAINLY MID TO UPPER 60S. LINGERING SHOWERS AND STORMS SHOULD DECREASE EARLY TUESDAY MORNING AND WARMING SHOULD HELP KEEP STORMS AWAY FOR MOST OF TUESDAY. HOWEVER SOME CHANCE WILL BE RESTORED MAINLY NORTH BY EARLY AFTERNOON AS BOUNDARIES PROVIDED BY NIGHTTIME STORMS MAY LINGER FOR A FOCUS...AND LATE DAY STORMS MAY DEVELOP MAINLY NORTHEAST FOR THE SAME REASON. FURTHER SOUTH...IT WILL BE HARD TO GET ANYTHING GOING MOST OF THE DAY DUE TO THE WARMING AND CAPPING. HOWEVER...THERE WILL BE A DISTINCT WAVE APPROACHING WHICH COULD TURN THAT AROUND...AGAIN THOUGH NOT UNTIL FAIRLY LATE IN THE DAY. TEMPERATURES SHOULD BE A LITTLE WARMER THAN TODAY THOUGH ANY 90 PLUS HIGHS SHOULD BE CONFINED TO SOUTH OF INTERSTATE 90. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 414 PM CDT MON JUN 24 2013 ALL MODELS ARE IN GOOD AGREEMENT IN BRINGING THE AFOREMENTIONED AND FAIRLY VIGOROUS SHORT WAVE THROUGH OUR NORTHERN AND SOME OF OUR EASTERN ZONES MAINLY TUESDAY EVENING. HAVE A HIGH DEGREE OF CONFIDENCE THAT SOME RAINFALL WILL OCCUR...JUST LIKELY NOT EVERYWHERE THROUGHOUT OUR NORTH AND EAST...THEREFORE PLACED COVERAGE POPS IN THOSE AREAS TUESDAY NIGHT INSTEAD OF UNCERTAINTY. THE HIGHEST ML CAPES EXIST TO THE WEST OF THE PRECIP AREAS. BUT STILL...ML CAPES OF OVER 1000 J/KG ARE NOTED IN OUR NORTH AND EAST COUPLED WITH 0 TO 3KM BULK SHEAR OF 25 TO 35 KNOTS EARLY IN THE EVENING. WITH 700MB TEMPERATURES CLOSE TO ONLY AROUND +10C...BELIEVE A LOW END SEVERE THREAT EXISTS IN OUR NORTH AND EAST EARLY IN THE EVENING...WITH HAIL AROUND THE SIZE OF QUARTERS OR HALF DOLLARS AND WIND GUSTS AROUND 60 MPH. THIS ACTIVITY SHOULD RAPIDLY MOVE EASTWARD THOUGH. OTHERWISE AFTER TUESDAY NIGHT...OUR WELL ADVERTISED UPPER RIDGING BEGINS TO TAKE HOLD WHICH WILL BEGIN TO QUIET DOWN OUR WEATHER. A COLD FRONT...MAINLY IN NAME ONLY...WILL SHIFT OUR WINDS TO THE NORTHWEST LATE TUESDAY NIGHT AND LASTING THROUGH THE DAY ON WEDNESDAY. WITH MIXING POTENTIAL AND NOT ANY BONAFIDE COOL AIR BEHIND THE WAVE...DO NOT EXPECT A LOT OF COOLING ON WEDNESDAY WITH WIDESPREAD 80S STILL PREVAILING. DEW POINTS WILL BE DOWN THOUGH AT LEAST WEST OF I 29. WITH LIGHT WINDS AND RELATIVELY DRIER AIR OOZING DOWN THROUGH THE AREA WEDNESDAY NIGHT...WE CAN EXPECT LOWS DOWN INTO THE LOWER 60S FOR MOST LOCATIONS. ON THURSDAY AS THE UPPER RIDGE BEGINS TO NUDGE WESTWARD...THERE IS SOME MODEL AGREEMENT IN BRINGING A WAVE DOWN OUR AREA FROM NORTHWEST TO SOUTHEAST WHICH COULD SPAWN SOME ACCAS SHOWERS OR THUNDERSTORMS. THE WAVE IS BASED AT 700MB...AND THE SOUNDINGS AND HUMIDITY TIME SECTIONS DO SHOW A PRETTY GOOD INCREASE IN MID LEVEL MOISTURE. THE 12Z NAM BLANKETS JUST ABOUT OUR ENTIRE FORECAST AREA WITH LIGHT PRECIPITATION. HOWEVER I CHOSE TO KEEP THE SMALL POPS IN OUR MISSOURI RIVER VALLEY ZONES WHERE THE STRONGEST PORTION OF THE 700MB DEFORMATION TAKES PLACE PROVIDING MID LEVEL CONVERGENCE... AND THIS IS JUXTAPOSED WITH A 700MB THERMAL GRADIENT GOING FROM +9C TO +12C IN THAT AREA. THURSDAYS HIGHS WILL STILL BE KIND OF WARM...WITH MID 80S TO AROUND 90 COMMON. THEN THINGS BEGIN TO CHANGE. BOTH THE ECMWF AND GFS ARE IN EXCELLENT AGREEMENT IN CONTINUING TO PUSH THE UPPER RIDGE WESTWARD...WHILE DEEPENING AN UPPER LOW OVER THE EASTERN UNITED STATES.. THIS CREATES A HIGH AMPLITUDE PATTERN WITH THE LATEST MODEL RUNS SHOWING A LOT OF SHORT WAVE ENERGY MOVING SOUTHWARD DOWN THE MISSISSIPPI VALLEY REGION. COOL HIGH PRESSURE BEGINS TO FILL IN DOWN FROM THE NORTHWEST AND THUS REALLY COOLS OFF OUR 850MB TEMPERATURES IN A BIG WAY. BY SUNDAY...THE ECMWF HAS +10C TO +14C AT 850MB IN OUR FORECAST AREA...WITH THE GFS EVEN COOLER. THEREFORE A COOLING TREND IS IN ORDER. FURTHERMORE...WITH THE SHORT WAVE ENERGY INTERACTING WITH COOL MID LEVEL TEMPERATURES... WOULD NOT RULE OUT SOME INSTABILITY SHOWERS IN OUR EASTERN ZONES THIS WEEKEND. THE POPS ON DAY 7 MONDAY ARE WISHY WASHY AND WERE MAINLY BASED ON A MORE SIGNIFICANT SHORT WAVE DIVING DOWN THE NORTHWEST FLOW ALOFT ON SOME PREVIOUS VERSION OF THE ECMWF. THE NEW 12Z ECMWF HAS BACKED OFF ON THIS IDEA WITH THE LARGE UPPER TROUGH CONTINUING JUST TO OUR EAST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 636 PM CDT MON JUN 24 2013 SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE MISSIOURI RIVER CORRIDOR THIS EVENING...THEN LIFT TO THE NORTH AND EAST OVERNIGHT. THIS WILL BRING A BRIEF PERIOD OF REDUCED CONDITIONS IN HEAVIER THUNDERSTORM ACTIVITY AT THE TAF SITES. MOST OF THE THUNDERSTORM ACTIVITY IS EXPECTED TO EXIT THE AREA BY MID TUESDAY MORNING...THOUGH COULD SEE REDEVELOPMENT GENERALLY NORTH OF INTERSTATE 90 IN THE AFTERNOON. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ UPDATE...CHAPMAN SHORT TERM...MJF LONG TERM...MJF AVIATION...JM
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1254 PM CDT SUN JUN 23 2013 .UPDATE...FOR 18Z TAFS. && .AVIATION... WEAK UPPER LOW JUST EAST OF THE PLATEAU EXPECTED TO TRANSITION INTO AN UPPER TROUGH OVER THE NEXT 24HRS. THIS WILL CONTINUE TO FOCUS CONVECTION CSV VICINITY INTO THE EVENING...WITH VERY LITTLE CHANCE BNA/CKV. BOUNDARY LAYER MOISTURE MORE ABUNDANT AS WELL WHICH COULD LEAD TO MVFR FOG OVERNIGHT BNA/CKV...WITH CEILINGS/VSBYS EVEN LOWER CSV. CONDITIONS WILL IMPROVE RAPIDLY 13-14Z MONDAY. && .PREV DISCUSSION... /ISSUED 1036 AM CDT SUN JUN 23 2013/ UPDATE...CELLS ARE ALREADY POPPING UP ALONG THE CUMBERLAND PLATEAU, WHERE SURFACE HUMIDITIES ARE HIGHEST. HRRR APPEARS TO HAVE A GOOD HANDLE ON THE CURRENT ACTIVITY, AND IT SUGGESTS NOTHING MORE THAN ISOLATED CONVECTION FOR THE REMAINDER OF MIDDLE TENNESSEE FOR THE AFTERNOON. SO WILL GO AHEAD AN INCREASE POP`S ALONG THE PLATEAU FOR THE REST OF TODAY AND LEAVE ISOLATED IN FOR EVERYONE ELSE. PREV DISCUSSION... /ISSUED 627 AM CDT SUN JUN 23 2013/ AVIATION... AFTER LOCAL 4SM BR DISSIPATES EXPECT VFR CONDITIONS AT ALL THREE TAF SITES THROUGH THE TAF PERIOD...UNLESS IMPACTED BY A STRONG STORM THEN MVFR VIS MAY BE RESULT IN A BRIEF DOWNPOUR. EXPECT THE DIURNLAL CU THAT HAS BEEN IMPACTING MIDDLE TENNESSEE OVER THE LAST FEW DAYS TO REDEVELOP AGAIN TODAY AFTER 16Z THIS MORNING...THEN DISSIPATE SOMETIME AFTER 00Z. ISOLATED CHANCES AT BEST FOR STRONG STORMS. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 07
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1036 AM CDT SUN JUN 23 2013 .UPDATE...CELLS ARE ALREADY POPPING UP ALONG THE CUMBERLAND PLATEAU, WHERE SURFACE HUMIDITIES ARE HIGHEST. HRRR APPEARS TO HAVE A GOOD HANDLE ON THE CURRENT ACTIVITY, AND IT SUGGESTS NOTHING MORE THAN ISOLATED CONVECTION FOR THE REMAINDER OF MIDDLE TENNESSEE FOR THE AFTERNOON. SO WILL GO AHEAD AN INCREASE POP`S ALONG THE PLATEAU FOR THE REST OF TODAY AND LEAVE ISOLATED IN FOR EVERYONE ELSE. && .PREV DISCUSSION... /ISSUED 627 AM CDT SUN JUN 23 2013/ AVIATION... AFTER LOCAL 4SM BR DISSIPATES EXPECT VFR CONDITIONS AT ALL THREE TAF SITES THROUGH THE TAF PERIOD...UNLESS IMPACTED BY A STRONG STORM THEN MVFR VIS MAY BE RESULT IN A BRIEF DOWNPOUR. EXPECT THE DIURNLAL CU THAT HAS BEEN IMPACTING MIDDLE TENNESSEE OVER THE LAST FEW DAYS TO REDEVELOP AGAIN TODAY AFTER 16Z THIS MORNING...THEN DISSIPATE SOMETIME AFTER 00Z. ISOLATED CHANCES AT BEST FOR STRONG STORMS. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ ROSE
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
224 AM CDT SUN JUN 23 2013 .DISCUSSION... RADAR SCOPE PPINE AS OF 07Z FOLLOWING AN ISOLATED THUNDERSTORM OVER DAVIDSON COUNTY BACK BEFORE MIDNIGHT. 850 MBAR DEWPOINTS POOLED ACROSS DAVIDSON COUNTY ON THE RUC BETWEEN 03Z AND 05Z POSSIBLY CONTRIBUTING TO THE FORMATION OF THE STORM. AT THE SAME TIME UPPER LEVEL LOW WAS SPINNING OVER EASTERN TENNESSEE. UK/NAM/GFS/GFSENSEMBLE AND ECMWF ALL SHOW THIS LOW LIFTING NORTH TODAY WITH BROAD UPPER RIDGE DEVELOPING OVER THE SOUTHERN US. THIS MEANS A SUMMER PATTERN WITH BERMUDA HIGH RIDGING IN OVER THE SOUTHEASTERN US FOR THE NEXT SEVERAL DAYS. BY THE LATTER PART OF THE WORK WEEK THE UPPER LEVEL HIGH WILL BE CENTERED OVER THE WESTERN US WITH TROUGHING OVER THE EASTERN US...BOTH EURO/ENSEMBLE AND GFS SHOW THIS DEVELOPING. WE ARE BASICALLY LOOKING AT SUMMER TYPE CONVECTION THAT COULD ALSO OCCUR NOCTURNALLY THIS TIME OF THE YEAR. AS THE TROUGH DEVELOPS OVER THE EASTERN US ON THURSDAY WE DO HAVE A FRONT DROPPING DOWN THIS WAY BUT SEEMS TO HAVE A HARD TIME GETTING VERY FAR SOUTH. TEMPS DO LOOK TO BACK OFF A LITTLE BY SUNDAY. OTHERWISE...LOOK FOR WARM DAYS AND NOT MUCH RELIEF AT NIGHT. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 90 70 88 70 / 20 20 30 30 CLARKSVILLE 90 69 87 69 / 20 20 20 20 CROSSVILLE 84 65 83 65 / 20 20 30 30 COLUMBIA 90 69 89 70 / 20 20 30 30 LAWRENCEBURG 90 68 90 69 / 20 20 30 30 WAVERLY 90 69 88 70 / 20 20 20 20 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ BOYD 01
AREA FORECAST DISCUSSION
NWS AMARILLO TX
319 PM CDT SUN JUN 23 2013 .DISCUSSION... JUST ONE MORE DAY OF THIS ACTIVE WEATHER PATTERN THAT THE REGION HAS BEEN UNDER FOR OVER A WEEK NOW. TONIGHT INTO TOMORROW...PRECIP CHANCES...THOUGH MENTIONABLE...CONTINUE TO DECLINE AS DRY AIR ADVECTION CONTINUES. PRECIPITABLE WATER VALUES ON THIS MORNINGS SOUNDING SHOW 0.79 INCHES...WHICH IS 92 PERCENT OF NORMAL...BUT A FAR CRY FROM THE 1 PLUS INCH VALUES WE/VE SEEN LATELY. IN ADDITION...IN THE WAKE OF THE UPPER LEVEL TROUGH THAT MOVE THROUGH EARLY THIS MORNING...THERE IS SOME UPPER LEVEL SHORT WAVE RIDGING OVER THE REGION. THIS SHOULD KEEP COVERAGE OF STORMS VERY LIMITED. HOWEVER...IT IS INTERESTING TO NOTE THAT THE RAP HIGH RESOLUTION MODEL SHOWS MORE COVERAGE THAN YESTERDAY. IF ANY STORMS DEVELOP EITHER THIS AFTERNOON OR TOMORROW...THE POTENTIAL REMAINS FOR MARGINALLY SEVERE HAIL AND DRY AND HYBRID DOWNBURSTS LEADING TO STRONG WINDS. TUESDAY THROUGH THURSDAY...INCREASING CONFIDENCE WITH VERY GOOD MODEL AGREEMENT AND CONSISTENCY THAT THE RIDGE WILL BUILD OVER THE SOUTHWEST THROUGH THIS PERIOD BRINGING A DRY AND HOT WEATHER PATTERN THROUGH THE WEEK. STAYED CLOSE TO THE PREVIOUS FORECAST STILL FAVORING HIGHER MAX TEMPS IN THE NORTHWESTERN PANHANDLES...WHICH HAVE SEEN VERY LITTLE RAIN...WHILE KEEPING THE SOUTHEASTERN TX PANHANDLE A FEW DEGREES LOWER DUE TO THE WET SOIL CONDITIONS. HOWEVER...BY THE END OF THE WEEK...THESE DIFFERENCES MAY BE NEGLIGIBLE AS THE SOILS DRY. FRIDAY THROUGH SUNDAY...MODELS CONTINUED THE TREND OF SHOWING A PERSISTENT RIDGE CONTINUING THROUGH THIS PERIOD. THE COLD FRONT WHICH WAS SHOWN IN THE GFS TO ARRIVE ON FRIDAY...HAS ALL BUT DISAPPEARED IN THE 12Z RUN. THUS...STAYED CLOSE TO THE PREVIOUS FORECAST WITH HOT AND DRY WEATHER CONTINUING THROUGH THE WEEK. JOHNSON && .AVIATION... FOR THE 18Z TAFS...ANY ISOLATED LATE AFTERNOON AND EARLY EVENING THUNDERSTORMS ARE EXPECTED TO REMAIN EAST OF TERMINALS. SCATTERED HIGH-BASED CUMULUS OR ALTOCUMULUS WILL BE THE ONLY CLOUDS OTHER THAN CIRRUS FOR THIS FORECAST. WIND SHIFT LINE WHICH IS MOVING ACROSS NORTHWESTERN PART OF FORECAST AREA WILL CAUSE VARIABILITY IN SURFACE WIND DIRECTION AT NORTHERN TERMINALS UNTIL AROUND 22 OR 23Z TODAY...WHEN SOUTHERLY SURFACE WINDS RESUME AND COMMENCE GUSTING TO AROUND 25 KT. FOR KAMA...SOUTHERLY SURFACE WINDS EXPECTED TO PREVAIL...WITH GUSTS ABOVE 25 KT OCCURRING BETWEEN 21Z TODAY AND 06Z MONDAY. VFR FORECAST CONTINUES NEXT 24 HOURS. NOTE TO USERS OF SURFACE OBSERVATION FROM RICK HUSBAND INTERNATIONAL AIRPORT KAMA...COMMUNICATIONS PROBLEM WITH DATA LINE HAS PREVENTED LONG-LINE DISSEMINATION OF SURFACE OBS. DATA COLLECTION PLATFORM AT KAMA ASOS IS FUNCTIONING PROPERLY WITH CONTINUOUS MONITORING OF ALL ELEMENTS BY AMARILLO NATIONAL WEATHER SERVICE FORECAST STAFF. COCKRELL && .FIRE WEATHER... ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS MAY OCCUR TOMORROW IN THE WESTERN OKLAHOMA AND FAR NORTHWESTERN TEXAS PANHANDLES...THOUGH UNCERTAINTY REMAINS. MINIMUM RELATIVE HUMIDITY VALUES SHOULD BE BELOW 15 PERCENT. HOWEVER...THOUGH WINDS ARE EXPECTED TO BE NEAR 20 MPH...IT IS UNCERTAIN IF THE SURFACE TROUGH WHICH RESULTED IN LIGHTER WINDS TODAY WILL BE A FACTOR TOMORROW AS WELL. THOUGH MINIMUM RELATIVE HUMIDITY VALUES WILL DROP BELOW 20 THROUGH THE REMAINDER OF THE WEEK...AS WE SEE A DRIER PATTERN...NO ADDITIONAL ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED AT THIS TIME AS WINDS SHOULD BE LIGHT. JOHNSON && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 97 68 95 68 98 / 20 5 5 5 0 BEAVER OK 98 71 97 72 99 / 10 20 20 20 0 BOISE CITY OK 100 65 100 68 101 / 10 10 5 5 0 BORGER TX 99 70 96 71 99 / 20 10 10 10 0 BOYS RANCH TX 100 70 98 68 102 / 20 5 5 5 0 CANYON TX 98 68 96 68 98 / 20 5 10 10 0 CLARENDON TX 96 68 94 70 96 / 20 20 20 20 0 DALHART TX 101 64 101 64 102 / 10 5 5 5 0 GUYMON OK 99 69 99 68 100 / 10 5 10 10 0 HEREFORD TX 99 67 94 66 98 / 20 5 5 5 0 LIPSCOMB TX 96 71 96 73 99 / 20 20 20 20 0 PAMPA TX 95 68 94 69 98 / 20 20 20 20 0 SHAMROCK TX 97 70 95 72 99 / 10 20 20 20 0 WELLINGTON TX 99 71 97 72 97 / 10 20 20 20 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 03/16
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1148 PM CDT SAT JUN 22 2013 .AVIATION... CONTINUED VFR CONDITIONS WITH MODEST SOUTHWEST FLOW ALOFT AND SURFACE TROUGH OVER THE HIGH PLAINS. THUNDER CHANCES MAY DEVELOP NEAR KLBB AGAIN SUNDAY LATE AFTERNOON AND EVENING...NOT CERTAIN ENOUGH TO INCLUDE MENTION AT THIS TIME IN THE TAFS. RMCQUEEN && .PREV DISCUSSION... /ISSUED 915 PM CDT SAT JUN 22 2013/ UPDATE... RETAINED ISOLATED THUNDER THIS EVENING ONLY IN THE SOUTHWESTERN SOUTH PLAINS WHERE SHOWERS HAVE AT LEAST BEEN FLIRTING WITH THE AREA. OTHERWISE...LATEST SHORT-TERM GUIDANCE HAS CONFIRMED MOST TRENDS THAT THUNDER CHANCES CONTINUE TO DWINDLE. UPDATED FOR LOWER THUNDERSTORM CHANCES AND REMOVAL OF SEVERE WORDING FOR THIS EVENING. RMCQUEEN PREV DISCUSSION... /ISSUED 723 PM CDT SAT JUN 22 2013/ UPDATE... THUNDERSTORM OPPORTUNITIES APPEAR DIMINISHING WITH DECREASING CUMULUS FIELD TO OUR SOUTHWEST...OVERSPREADING HIGH CLOUDS WITH SLOWLY FALLING TEMPERATURES...AND STILL 40 TO 60 JOULES PER KILOGRAM OF CONVECTIVE INHIBITION TO OVERCOME. LATEST RAP SPREADS EVEN HIGHER INHIBITION AIRMASS INTO THE AREA BY 02Z-03Z WITH LATEST RUN INDICATING ONLY VERY ISOLATED STORMS IN THE NEXT HOUR OR TWO....WHILE THE HRRR HAS BEEN FAR OVERDONE AND TOO FAST WITH DEVELOPMENT TO OUR NORTH...BUT AT LEAST HAS BEEN PLAYING DOWN THUNDER DEVELOPMENT OVER MUCH OF THE SOUTH PLAINS AREA. CONVECTIVE ENERGY SHOULD IT BE RELEASED AND COMBINED WITH 30-35 KNOTS OF DEEP LAYER SHEAR WOULD INDICATE A POTENTIAL FOR SEVERE STORMS YET...SO WE WILL MAINTAIN CURRENT FORECAST OF LOW THUNDER CHANCES FOR NOW. RMCQUEEN AVIATION... VFR WITH MODERATE SURFACE TROUGH AND UPPER LEVEL SOUTHWEST FLOW WILL DOMINATE. THUNDER CHANCES APPEAR ONLY MARGINAL AT THIS POINT MAINLY FOR KLBB THIS EVENING...SO WE WILL NOT INCLUDE MORE THAN A VICINITY MENTION IN THE KLBB TAF FOR NOW. RMCQUEEN PREV DISCUSSION... /ISSUED 325 PM CDT SAT JUN 22 2013/ SHORT TERM... THE PRIMARY FOCUS REMAINS ON CONVECTIVE CHANCES LATE THIS AFTERNOON INTO THE EVENING AND AGAIN ON STORM CHANCES LATE TOMORROW AFTERNOON...INCLUDING THE PROSPECTS FOR SEVERE WEATHER. LARGE SCALE PATTERN WILL NOT CHANGE MUCH LOCALLY AS THE REGION REMAINS ON THE SOUTHERN FRINGE OF SOUTHWESTERLY FLOW ALOFT. ONE PRONOUNCED SHORTWAVE TROUGH WILL LIFT ACROSS THE NORTHERN HIGH PLAINS TONIGHT WHILE WATER VAPOR IMAGERY DOES SHOW INCREASING SUPPORT/MOISTENING APPROACHING THROUGH NM AND AZ. WEAK SUPPORT ALOFT COUPLED WITH A DRYLINE CURRENTLY TIGHTENING ACROSS THE FAR WESTERN ZONES SHOULD BE ENOUGH TO TRIGGER SCATTERED CONVECTION BY LATE THIS AFTERNOON OR EARLY THIS EVENING. STRONG INSTABILITY ALONG AND ESPECIALLY JUST EAST OF THE DRYLINE AND IMPROVING 0-6 KM SHEAR WILL SUPPORT A SEVERE WEATHER RISK INTO THIS EVENING...INCLUDING DAMAGING WINDS AND LARGE HAIL. IN ADDITION...STORM MOTIONS WILL BE FAIRLY SLOW...PARTICULARLY IF ANY MID-LEVEL CYCLONIC ROTATION CAN BE ACQUIRED /WHICH WILL BE POSSIBLE/ AND GIVEN ABOVE AVERAGE PWATS IN PLACE...A LOCALIZED HEAVY RAIN THREAT WILL EXIST. IN GENERAL...THIS ACTIVITY WILL ADVANCE EASTWARD BUT WILL LIKELY HAVE DIFFICULTY MOVING TOO FAR OFF INTO THE ROLLING PLAINS GIVEN THE STRONGER INHIBITION PROGGED THERE. CONVECTION WILL WANE LATE TONIGHT BUT A SIMILAR SETUP WILL REDEVELOP ON SUNDAY SETTING THE STAGE FOR ANOTHER CHANCE OF STORMS...PRIMARILY ON THE CAPROCK. LATEST GUIDANCE DOES SUGGEST MOISTURE...INSTABILITY AND SHEAR WILL BE LOWER THAN TODAY SO THIS MAY MODULATE STORM COVERAGE AND INTENSITY SUNDAY AFTERNOON. OTHERWISE...MILD CONDITIONS WILL CONTINUE WITH LOWS TONIGHT RANGING FROM THE MID 60S NORTHWEST TO MID 70S SOUTHEAST AND AFTERNOON HIGHS ON SUNDAY WELL INTO THE 90S. LONG TERM... NO SIGNIFICANT CHANGES TO THE FCST THIS AFTN. STILL APPEARS THAT MONDAY WILL BE THE LAST DAY TO SEE THUNDERSTORMS IN THE LOW LEVEL MOISTURE AXIS UNDERNEATH SWLY MID TO UPPER LEVEL FLOW BEFORE UPPER RIDGING BUILDS OVER THE ROCKIES. THAT RIDGE SHOULD SHUT EFFECTIVELY SHUT OFF PRECIP CHANCES FOR TUESDAY THROUGH THURSDAY AND INCREASED HEIGHTS AND THICKNESSES CONTINUE TO SUGGEST WARMER TEMPERATURES...BUT STAYING AWAY FROM EXTREME HEAT WITH THE HEIGHT AND THERMAL RIDGES CENTERED OVER COLORADO AND NORTHERN NEW MEXICO. STILL A SIGNAL IN THE MEDIUM RANGE OF PRECIP WORKING INTO THE FCST AREA FRIDAY AND/OR SATURDAY AS THE UPPER RIDGE SHIFTS WWD TOWARD UTAH AND ARIZONA ALLOWING DEEPER NORTHERLY FLOW TO DEVELOP ACROSS THE PLAINS AND THUS THE POSSIBILITY OF A COLD FRONT AND UPPER DISTURBANCES TO ADVANCE TOWARD THE AREA. WILL NUDGE POPS TOWARD SLIGHT CHANCE BUT KEEP THEM JUST BELOW MENTION WAITING TO SEE IF FUTURE RUNS CONTINUE TO ADVERTISE THIS PATTERN. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 64 94 66 93 66 / 10 20 20 20 20 TULIA 66 93 67 94 67 / 10 20 20 20 20 PLAINVIEW 68 92 67 93 69 / 10 20 20 20 20 LEVELLAND 65 94 68 92 69 / 10 20 20 20 20 LUBBOCK 70 94 69 94 71 / 10 20 20 20 20 DENVER CITY 66 97 69 94 69 / 20 20 20 20 20 BROWNFIELD 65 95 68 92 69 / 20 20 20 20 20 CHILDRESS 72 96 70 96 71 / 10 10 10 10 10 SPUR 70 93 70 94 71 / 10 10 10 10 10 ASPERMONT 75 96 71 97 73 / 10 10 10 10 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/05
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1053 PM CDT MON JUN 24 2013 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .UPDATE... ISSUED AT 921 PM CDT MON JUN 24 2013 MCV OVER SOUTHERN MN AND 35 KT LLJ OVER IOWA HAS CAUSED CONVECTION TO INCREASE OVER SE MN/NE IA THIS EVENING. THIS CONVECTION SHOULD AFFECT AT LEAST OUR SOUTHERN COUPLE TIERS OF COUNTIES OVERNIGHT. CURRENT TIMING SUGGESTS THAT IT WILL REACH OUR FAR SW COUNTIES AROUND MIDNIGHT. HAVE INCREASED POPS TO LIKELY OVER PARTS OF C/EC WI OVERNIGHT AND INCREASED QPF AMOUNTS TO A HALF TO TWO-THIRDS OF AN INCH FROM WAUTOMA TO OSHKOSH TO MANITOWOC. ONLY KEPT LOW-END POPS OVER NC/FAR NE WI...WHICH BLENDED WELL WITH DLH/MQT. NOT EXPECTING ANY SEVERE WEATHER OVERNIGHT...AS MUCAPE HAS DECREASED TO LESS THAN 1000 J/KG AND DEEP LAYER SHEAR IS ONLY AROUND 20 KTS. HOWEVER...LOCALLY HEAVY RAINFALL REMAINS A CONCERN IN OUR FAR SOUTHERN COUNTIES. && .SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 226 PM CDT MON JUN 24 2013 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE TROUGH MOVING ENE OVER FAR EASTERN SOUTH DAKOTA AND INTO SOUTHWEST MINNESOTA. AREA OF CONVECTION AHEAD OF THIS TROUGH IS DRAWING CLOSER TO THE SW WISCONSIN BORDER. CLOUD COVER OVER CENTRAL AND EAST-CENTRAL WISCONSIN HAS LIMITED HEATING SOMEWHAT TODAY...BUT ML CAPES ARE APPROACHED A 1K J/KG...THOUGH STILL HAVE SOME CIN TO OVERCOME. NOT SURE IF THIS INHIBITION WILL GET OVERCOME...SINCE CLOUDS WILL ONLY THICKEN FROM HERE ON OUT. MOSTLY CLEAR SKIES EXIST BEHIND THIS SHORTWAVE OVER THE CENTRAL PLAINS...AND THE NEXT SHORTWAVE IS MOVING OVER THE CENTRAL ROCKIES. MAIN FORECAST CONCERNS INCLUDE PRECIP CHANCES TONIGHT...AND SEVERE WEATHER CHANCES TOMORROW. TONIGHT...THE SHORTWAVE TROUGH MOVING INTO FAR SOUTHWEST MINNESOTA WILL CONTINUE TO TRACK ENE ACROSS SOUTHERN MINNESOTA AND THE NORTHERN HALF OF WISCONSIN THIS EVENING. CURRENT TRAJECTORY OF PRECIPITATION WILL PLACE THE BEST CHANCES SOUTH OF A TOMAHAWK TO IRON MOUNTAIN LINE. WITH CLOUD COVER KEEPING TEMPERATURES IN THE UPPER 70S TO LOWER 80S OVER CENTRAL AND EAST-CENTRAL WISCONSIN...THE STORMS WILL HAVE SOME CIN TO OVERCOME DESPITE ML CAPES AROUND 1000 J/KG. THINKING SEVERE CHANCES IS RATHER REMOTE SINCE THE NORTHERN END OF THE THUNDERSTORM COMPLEX IS MOSTLY STRATIFORM. PWATS WILL BE INCREASING OVER 1.50 INCHES SO THINKING HEAVY RAINFALL WILL BE THE MAIN THREAT WITH THESE STORMS...BUT EVEN THAT DOES LOOK THAT POSSIBLE. SHOWERS AND STORMS WILL HAVE MOSTLY EXITED THE REGION BY LATE IN THE EVENING...AND THEY SHOULD LAY OUT AN OUTFLOW BOUNDARY OVER SOUTHERN WISCONSIN OR POINTS FURTHER SOUTH. RETURN FLOW WILL REDEVELOP OVER THE NORTHERN PLAINS LATE SO THINKING ANY CONVECTION LATE TONIGHT WILL FALL ALONG THIS OUTFLOW BOUNDARY. HAVE DROPPED POPS SIGNIFICANTLY AFTER MIDNIGHT AND ACROSS NORTHERN WISCONSIN. MUGGY LOWS IN THE MIDDLE 60S. TUESDAY...MUCH OF THE DETAILS IN TOMORROWS WEATHER WILL REVOLVE AROUND WHERE RESULTING OUTFLOW BOUNDARIES END UP AND HOW QUICKLY THE ATMOSPHERE CAN RECOVER. IF THE LAST FEW DAYS ARE ANY INDICATION...IT COULD TAKE UNTIL MID TO LATE AFTERNOON FOR DESTABILIZATION TO OCCUR. BY THIS TIME...RETURN FLOW WILL BE SPREADING NORTHEAST INTO THE REGION AS A SHORTWAVE CURRENTLY OVER COLORADO LIFTS INTO THE NORTHERN MISSISSIPPI VALLEY. DO NOT TRUST MODEL SOUNDINGS MUCH...BUT TEMPS IN THE LOW TO MID 80S AND DEWPOINTS IN THE UPPER 60S SHOULD YIELD AT LEAST 1000 J/KG OF CAPE. 0-6KM BULK SHEAR IS RATHER POOR AROUND 20 KTS...SO WILL BE TOUGH TO GET ANY ORGANIZED CONVECTION. BUT CANNOT RULE OUT AN ISOLATED MENTION IF THE INSTABILITY RECOVERS. HIGHS IN THE LOW TO MID 80S. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 226 PM CDT MON JUN 24 2013 BRIEF PERIOD OF ZONAL FLOW WILL BE ACCOMPANIED BY PRIMARY SHORTWAVE FORECAST TO TRAVERSE THE WESTERN GREAT LAKES DURING THE MIDDLE OF THE WORK WEEK. THERAFTER...THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTIZE PRONOUNCED RIDGING OVER THE WESTERN CONUS WITH DEEPENING DOWNSTREAM TROUGH ACROSS THE GREAT LAKES AND OHIO VALLEY. LOTS OF UNCERTAINTY WITH RESPECT TO THE DETAILS OF EMBEDDED DISTURBANCES WITHIN THE INCREASING NORTHWESTERLY FLOW OVER THE STATE LATE IN THE WORK WEEK. DAILY AVERAGE TEMPERATURES SHOULD REMAIN ABOVE NORMAL...THEN FALL OFF CLOSER TO NORMAL OR PERHAPS A LITTLE BELOW NORMAL BY THE WEEKEND. TUESDAY NIGHT AND WEDNESDAY... PRIMARY FORECAST CHALLENGE EARLY IN THE EXTENDED WILL BE TRYING TO NARROW DOWN THE TIMING AND LOCATION OF CONVECTIVE ACTIVITY ASSOCIATED WITH THE PRIMARY SHORTWAVE DISTURBANCE TUESDAY NIGHT AND WEDNESDAY. FORECAST CONFIDENCE FOR THIS PERIOD IS LOW. NOT GOING TO BUCK TRENDS PAST FEW DAYS AND WILL BET AGAINST QUASISTATIONARY FRONTAL BOUNDARY NEAR THE ILLINOIS-WISCONSIN MAKING MUCH NORTHWARD PROGRESS INTO THE FORECAST AREA TUESDAY NIGHT DESPITE RATHER ROBUST SOUTHWESTERLY LOW-LEVEL FLOW AHEAD OF THE APPROACHING SHORTWAVE. LATEST MODEL TRENDS SEEM TO SUGGEST THAT BULK OF DEEP CONVECTION WILL FIRE ALONG BOUNDARY TO OUR SOUTHWEST AROUND 00Z WEDNESDAY THEN HEAD MORE EASTERLY MAINLY ACROSS THE SOUTHERN THIRD OF THE STATE TUESDAY NIGHT...AS LLJ VEERS WSW BY 12Z WEDNESDAY. WILL TWEAK POPS SOMEWHAT TUESDAY PLACING HIGHEST PROBABALITIES ACROSS THE SOUTHERN THIRD OF THE FORECAST AREA AND TAPERING TO CHANCE ACROSS THE FAR NORTHEAST. IF THIS SCENARIO PLAYS OUT...FEEL BEST COMBINATION OF SHEAR AND INSTABLITY SUPPORTAIVE OF SEVERE STORMS WILL ALSO BE FOCUSED GENERALLY SOUTH OF HIGHWAY 29 TUESDAY NIGHT. PW VALUES FORECAST TO REMAIN QUITE HIGH...NEARLY 2SD ABOVE NORMAL TUESDAY NIGHT...THUS LOCALLY HEAVY RAINFALL IS ALSO THREAT. AS SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW MOVE ACROSS THE FORECAQST AREA WEDNESDAY EXPECT MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY OVER THE ENTIRE FORECAST AREA. AT THIS TIME APPEARS WILL BE CONSIDERABLE CLOUDS AROUND DURING THE DAY ON WEDNESDAY THUS FEEL SEVERE THREAT WILL BE MARGINAL. AGAIN SOME POTENTIAL FOR LOCALLY HEAVY RAINFALL ESPECIALLY OVER THE FOX VALLEY. WILL TREND MAX TEMPS A FEW DEGREES LOWER WEDNESDAY ASSUMING MORE WIDESPREAD PRECIPITATION AND CLOUD COVER. /EB/ THURSDAY INTO THE WEEKEND... LONG RANGE MODELS IN AGREEMENT ON DEVELOPMENT OF HUGE UPPER RIDGE OVER 110 W LATITUDE AND TROF OVER GREAT LAKES. THIS SPELLS A SHOWERY PERIOD WITH TEMPS AOB NORMAL ACROSS REGION FRIDAY INTO MONDAY. BOTH ECMWF AND GFS SHOW SIGNS OF ADDITIONAL ENERGY DIGGING INTO TROF NEXT WEEK...KEEPING THE COOLISH WEATHER AROUND. /JKL/. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1047 PM CDT MON JUN 24 2013 CONVECTION HAS STEADILY INCREASED OVER SE MN/NE IA THIS EVENING. THE NORTHERN EDGE OF THIS SHOULD MOVE THROUGH PARTS OF C/EC WI OVERNIGHT...THEN EXIT EASTERN WI EARLY TUESDAY MORNING. WILL CARRY A TEMPO GROUP FOR TSTMS IN THE ATW/GRB TAFS LATE TONIGHT. MAINLY DRY CONDITIONS ARE EXPECTED OVER NORTHERN WI...BUT SOME PATCHY MVFR/IFR FOG IS POSSIBLE AT THE RHI TAF SITE. CONFIDENCE IS LOW IN THE REST OF THE PCPN FCST...BUT THINK THAT MOST OF THE TSTM ACTIVITY WILL REMAIN SOUTH OF THE TAF SITES ON TUESDAY AFTERNOON AND EVENING...SINCE THE FRONTAL BOUNDARY IS EXPECTED TO RESIDE OVER SOUTHERN WI. DID MENTION A PROB30 GROUP FOR TSTMS AT THE SOUTHERN TAF SITES DURING THE EVENING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........KIECKBUSCH SHORT TERM.....MPC LONG TERM......JKL AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
933 PM CDT MON JUN 24 2013 NEW INFORMATION ADDED TO UPDATE SECTION .UPDATE... ISSUED AT 921 PM CDT MON JUN 24 2013 MCV OVER SOUTHERN MN AND 35 KT LLJ OVER IOWA HAS CAUSED CONVECTION TO INCREASE OVER SE MN/NE IA THIS EVENING. THIS CONVECTION SHOULD AFFECT AT LEAST OUR SOUTHERN COUPLE TIERS OF COUNTIES OVERNIGHT. CURRENT TIMING SUGGESTS THAT IT WILL REACH OUR FAR SW COUNTIES AROUND MIDNIGHT. HAVE INCREASED POPS TO LIKELY OVER PARTS OF C/EC WI OVERNIGHT AND INCREASED QPF AMOUNTS TO A HALF TO TWO-THIRDS OF AN INCH FROM WAUTOMA TO OSHKOSH TO MANITOWOC. ONLY KEPT LOW-END POPS OVER NC/FAR NE WI...WHICH BLENDED WELL WITH DLH/MQT. NOT EXPECTING ANY SEVERE WEATHER OVERNIGHT...AS MUCAPE HAS DECREASED TO LESS THAN 1000 J/KG AND DEEP LAYER SHEAR IS ONLY AROUND 20 KTS. HOWEVER...LOCALLY HEAVY RAINFALL REMAINS A CONCERN IN OUR FAR SOUTHERN COUNTIES. && .SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 226 PM CDT MON JUN 24 2013 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE TROUGH MOVING ENE OVER FAR EASTERN SOUTH DAKOTA AND INTO SOUTHWEST MINNESOTA. AREA OF CONVECTION AHEAD OF THIS TROUGH IS DRAWING CLOSER TO THE SW WISCONSIN BORDER. CLOUD COVER OVER CENTRAL AND EAST-CENTRAL WISCONSIN HAS LIMITED HEATING SOMEWHAT TODAY...BUT ML CAPES ARE APPROACHED A 1K J/KG...THOUGH STILL HAVE SOME CIN TO OVERCOME. NOT SURE IF THIS INHIBITION WILL GET OVERCOME...SINCE CLOUDS WILL ONLY THICKEN FROM HERE ON OUT. MOSTLY CLEAR SKIES EXIST BEHIND THIS SHORTWAVE OVER THE CENTRAL PLAINS...AND THE NEXT SHORTWAVE IS MOVING OVER THE CENTRAL ROCKIES. MAIN FORECAST CONCERNS INCLUDE PRECIP CHANCES TONIGHT...AND SEVERE WEATHER CHANCES TOMORROW. TONIGHT...THE SHORTWAVE TROUGH MOVING INTO FAR SOUTHWEST MINNESOTA WILL CONTINUE TO TRACK ENE ACROSS SOUTHERN MINNESOTA AND THE NORTHERN HALF OF WISCONSIN THIS EVENING. CURRENT TRAJECTORY OF PRECIPITATION WILL PLACE THE BEST CHANCES SOUTH OF A TOMAHAWK TO IRON MOUNTAIN LINE. WITH CLOUD COVER KEEPING TEMPERATURES IN THE UPPER 70S TO LOWER 80S OVER CENTRAL AND EAST-CENTRAL WISCONSIN...THE STORMS WILL HAVE SOME CIN TO OVERCOME DESPITE ML CAPES AROUND 1000 J/KG. THINKING SEVERE CHANCES IS RATHER REMOTE SINCE THE NORTHERN END OF THE THUNDERSTORM COMPLEX IS MOSTLY STRATIFORM. PWATS WILL BE INCREASING OVER 1.50 INCHES SO THINKING HEAVY RAINFALL WILL BE THE MAIN THREAT WITH THESE STORMS...BUT EVEN THAT DOES LOOK THAT POSSIBLE. SHOWERS AND STORMS WILL HAVE MOSTLY EXITED THE REGION BY LATE IN THE EVENING...AND THEY SHOULD LAY OUT AN OUTFLOW BOUNDARY OVER SOUTHERN WISCONSIN OR POINTS FURTHER SOUTH. RETURN FLOW WILL REDEVELOP OVER THE NORTHERN PLAINS LATE SO THINKING ANY CONVECTION LATE TONIGHT WILL FALL ALONG THIS OUTFLOW BOUNDARY. HAVE DROPPED POPS SIGNIFICANTLY AFTER MIDNIGHT AND ACROSS NORTHERN WISCONSIN. MUGGY LOWS IN THE MIDDLE 60S. TUESDAY...MUCH OF THE DETAILS IN TOMORROWS WEATHER WILL REVOLVE AROUND WHERE RESULTING OUTFLOW BOUNDARIES END UP AND HOW QUICKLY THE ATMOSPHERE CAN RECOVER. IF THE LAST FEW DAYS ARE ANY INDICATION...IT COULD TAKE UNTIL MID TO LATE AFTERNOON FOR DESTABILIZATION TO OCCUR. BY THIS TIME...RETURN FLOW WILL BE SPREADING NORTHEAST INTO THE REGION AS A SHORTWAVE CURRENTLY OVER COLORADO LIFTS INTO THE NORTHERN MISSISSIPPI VALLEY. DO NOT TRUST MODEL SOUNDINGS MUCH...BUT TEMPS IN THE LOW TO MID 80S AND DEWPOINTS IN THE UPPER 60S SHOULD YIELD AT LEAST 1000 J/KG OF CAPE. 0-6KM BULK SHEAR IS RATHER POOR AROUND 20 KTS...SO WILL BE TOUGH TO GET ANY ORGANIZED CONVECTION. BUT CANNOT RULE OUT AN ISOLATED MENTION IF THE INSTABILITY RECOVERS. HIGHS IN THE LOW TO MID 80S. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 226 PM CDT MON JUN 24 2013 BRIEF PERIOD OF ZONAL FLOW WILL BE ACCOMPANIED BY PRIMARY SHORTWAVE FORECAST TO TRAVERSE THE WESTERN GREAT LAKES DURING THE MIDDLE OF THE WORK WEEK. THERAFTER...THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTIZE PRONOUNCED RIDGING OVER THE WESTERN CONUS WITH DEEPENING DOWNSTREAM TROUGH ACROSS THE GREAT LAKES AND OHIO VALLEY. LOTS OF UNCERTAINTY WITH RESPECT TO THE DETAILS OF EMBEDDED DISTURBANCES WITHIN THE INCREASING NORTHWESTERLY FLOW OVER THE STATE LATE IN THE WORK WEEK. DAILY AVERAGE TEMPERATURES SHOULD REMAIN ABOVE NORMAL...THEN FALL OFF CLOSER TO NORMAL OR PERHAPS A LITTLE BELOW NORMAL BY THE WEEKEND. TUESDAY NIGHT AND WEDNESDAY... PRIMARY FORECAST CHALLENGE EARLY IN THE EXTENDED WILL BE TRYING TO NARROW DOWN THE TIMING AND LOCATION OF CONVECTIVE ACTIVITY ASSOCIATED WITH THE PRIMARY SHORTWAVE DISTURBANCE TUESDAY NIGHT AND WEDNESDAY. FORECAST CONFIDENCE FOR THIS PERIOD IS LOW. NOT GOING TO BUCK TRENDS PAST FEW DAYS AND WILL BET AGAINST QUASISTATIONARY FRONTAL BOUNDARY NEAR THE ILLINOIS-WISCONSIN MAKING MUCH NORTHWARD PROGRESS INTO THE FORECAST AREA TUESDAY NIGHT DESPITE RATHER ROBUST SOUTHWESTERLY LOW-LEVEL FLOW AHEAD OF THE APPROACHING SHORTWAVE. LATEST MODEL TRENDS SEEM TO SUGGEST THAT BULK OF DEEP CONVECTION WILL FIRE ALONG BOUNDARY TO OUR SOUTHWEST AROUND 00Z WEDNESDAY THEN HEAD MORE EASTERLY MAINLY ACROSS THE SOUTHERN THIRD OF THE STATE TUESDAY NIGHT...AS LLJ VEERS WSW BY 12Z WEDNESDAY. WILL TWEAK POPS SOMEWHAT TUESDAY PLACING HIGHEST PROBABALITIES ACROSS THE SOUTHERN THIRD OF THE FORECAST AREA AND TAPERING TO CHANCE ACROSS THE FAR NORTHEAST. IF THIS SCENARIO PLAYS OUT...FEEL BEST COMBINATION OF SHEAR AND INSTABLITY SUPPORTAIVE OF SEVERE STORMS WILL ALSO BE FOCUSED GENERALLY SOUTH OF HIGHWAY 29 TUESDAY NIGHT. PW VALUES FORECAST TO REMAIN QUITE HIGH...NEARLY 2SD ABOVE NORMAL TUESDAY NIGHT...THUS LOCALLY HEAVY RAINFALL IS ALSO THREAT. AS SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW MOVE ACROSS THE FORECAQST AREA WEDNESDAY EXPECT MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY OVER THE ENTIRE FORECAST AREA. AT THIS TIME APPEARS WILL BE CONSIDERABLE CLOUDS AROUND DURING THE DAY ON WEDNESDAY THUS FEEL SEVERE THREAT WILL BE MARGINAL. AGAIN SOME POTENTIAL FOR LOCALLY HEAVY RAINFALL ESPECIALLY OVER THE FOX VALLEY. WILL TREND MAX TEMPS A FEW DEGREES LOWER WEDNESDAY ASSUMING MORE WIDESPREAD PRECIPITATION AND CLOUD COVER. /EB/ THURSDAY INTO THE WEEKEND... LONG RANGE MODELS IN AGREEMENT ON DEVELOPMENT OF HUGE UPPER RIDGE OVER 110 W LATITUDE AND TROF OVER GREAT LAKES. THIS SPELLS A SHOWERY PERIOD WITH TEMPS AOB NORMAL ACROSS REGION FRIDAY INTO MONDAY. BOTH ECMWF AND GFS SHOW SIGNS OF ADDITIONAL ENERGY DIGGING INTO TROF NEXT WEEK...KEEPING THE COOLISH WEATHER AROUND. /JKL/. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 632 PM CDT MON JUN 24 2013 TSTM COMPLEX MOVED THROUGH NORTHERN IL LATE THIS AFTERNOON...WITH ONLY ISOLD SHRA/TSRA OVER CENTRAL/NORTHERN WI. SEEING SOME SIGNS THAT CONVECTION IS SLOWLY INCREASING NEAR THE MN/IA BORDER...AND THIS COULD BE THE START OF ANOTHER CLUSTER OF STORMS WHICH COULD EVENTUALLY PUSH THROUGH CENTRAL/EAST CENTRAL WI OVERNIGHT. THE REMNANTS OF THIS TSTM COMPLEX SHOULD PULL OUT OF THE REGION EARLY TUESDAY...WITH SCT TSTMS POSSIBLY REDEVELOPING LATE IN THE AFTERNOON. HAVE TRENDED TAFS IN THIS DIRECTION...BUT WILL NEED TO WATCH TRENDS OVER THE NEXT COUPLE HOURS TO SEE IF THIS THINKING IS ON TRACK. FOR NOW... HAVE LEFT THE RHI TAF DRY... ALTHOUGH ISOLD SHRA/TSRA MY GET CLOSE EARLY THIS EVENING. DID ADD SOME IFR FOG AT RHI LATE TONIGHT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........KIECKBUSCH SHORT TERM.....MPC LONG TERM......JKL AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
903 PM CDT MON JUN 24 2013 .UPDATE... ACTIVE WEATHER PATTERN FOR THE MIDWEST WILL CONTINUE. WATER VAPOR AND 500 MB RAP SHOWS ANOTHER UPSTREAM SHORTWAVE OVER SOUTHERN MINNESOTA WITH A STRONGER ONE OVER THE CENTRAL PLAINS. THE MINNESOTA SHORTWAVE WILL PUSH INTO SOUTHERN WISCONSIN TONIGHT AND THE PLAINS SHORTWAVE WILL AFFECT SOUTHERN WISCONSIN MIDDAY TUESDAY. PRECIPITABLE WATER AROUND 1.4 INCHES SHOULD INCREASE TO 1.75 INCHES BY SUNRISE AND NEAR 2 INCHES NEAR THE ILLINOIS BORDER BY NOON TUESDAY. MEANWHILE THE NOSE OF THE 850 MB LOW LEVEL JET ACROSS KANSAS AND MISSOURI WILL MOVE ACROSS NORTHERN ILLINOIS AND BECOME MORE WEST LATE TONIGHT. THEN THE SOUTHWEST 850 MB FLOW INCREASES AGAIN INTO SOUTHERN WISCONSIN TUESDAY EVENING. THEREFORE EXPECT MORE THUNDERSTORMS LATE TONIGHT AND AGAIN TUESDAY AND TUESDAY NIGHT. BEST FOCUS FOR HEAVY RAINS MAY STAY JUST WEST AND SOUTH TONIGHT...IN AREA OF CURRENT 850 MB MOISTURE TRANSPORT...THEN EVENTUALLY MOVE INTO SOUTHERN WISCONSIN TUESDAY OR TUESDAY EVENING. HOWEVER STORMS MAY BE FARTHER NORTH TONIGHT CLOSER TO APPROACHING SHORTWAVE. && .AVIATION/06Z TAFS/... EXPECT MAINLY VFR CONDITIONS EARLY TONIGHT...BUT MAY SEE SOME IFR CIGS/FOG DUE TO MOIST LOW LEVELS. ALSO THUNDERSTORMS MAY DEVELOP TONIGHT AND MORE EXPECTED TUESDAY. && .PREV DISCUSSION... /ISSUED 334 PM CDT MON JUN 24 2013/ VERY SHORT TERM...TONIGHT AND TUESDAY. TONIGHT - CONFIDENCE...LOW EXPECTING A WEAKENED VERSION OF IOWA COMPLEX TO TRAVERSE ACROSS THE CWA LATER THIS AFTERNOON AND EARLY EVENING. STRONGEST PORTION OF IOWA COMPLEX WILL LIKELY RIDE THE MLCAPE GRADIENT IN NORTHERN IL PER SPC MESO ANALYSIS...BUT SOME INCREASE INSTABILITY SNEAKING BACK NORTH TOWARDS THE SRN COUNTIES. IN FACT 3 HOURLY MLCAPE CHANGE WHILE GREATEST IN NRN IL...DOES SHOW AN AXIS INTO THE FAR SOUTH. THIS CLOSE ENOUGH CALL IN THE SOUTHERN TIER OF COUNTIES FOR THE SVR WATCH FROM SPC. LIKE LAST NIGHT THE MAIN CHALLENGE IS THE DEGREE AND LOCATION OF REDEVELOPMENT BECOMES THE KEY QUESTION. GETTING MODEL SOLUTIONS ALL OVER THE MAP FROM HEAVY RAINS...TO SCATTERED DEVELOPMENT TO NEXT TO NOTHING. MODELS CONSENSUS OF 850 MILLIBAR JET CORE LOOKS VERY SIMILAR TO WHERE WE NOTICED IT SUNDAY PROGGD FOR 12Z THIS MORNING. AND GIVEN WHERE ONGOING CONVECTION IS LAYING ITSELF OUT HAVE SOME CONCERN THAT IT MAY BE ANOTHER GLANCING SHOT ONCE AGAIN. HRRR DOES SHOW SOME ELEVATED DEVELOPMENT LATER TONIGHT. SO CERTAINLY WORTHY OF KEEPING THE WATCH GOING FOR NOW. TUESDAY - CONFIDENCE...MEDIUM AXIS OF LOW LEVEL JET TRANSLATES EAST A BIT AND IS AIMED MORE TOWARDS SOUTHERN WI. 500 MILLIBAR SHOWS PERIODIC VORTICITY MAXIMA WAVERING THROUGH THE WEAK WESTERLY FLOW. SOME UPPER DIVERGENCE NOTED AS WELL...THOUGH OVERALL JET ACTION LOOKS PRETTY WEAK. CWASP NUMBERS IN THE 60S...A FEW LOW 70S OFF THE NAM. BUT NOTHING EXTREME. WILL KEEP HIGH END CHANCE/LIKELY POPS GOING WITH THE OVERALL PATTERN STILL FAVORING CONVECTION DUE INSTABILITY AND RIPPLES IN THE FLOW. SHORT TERM...TUESDAY NIGHT THROUGH THURSDAY. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...FORECAST CONFIDENCE LOW TO MEDIUM. EVOLUTION FROM MOIST AND UNSTABLE NEAR-ZONAL WSW FLOW TO COOLER AND DRIER NW FLOW BEGINS WITH APPROACH OF SHORT WAVE TROUGH AND ASSOCIATED SURFACE LOW FROM THE DAKOTAS TUESDAY NIGHT...AND THEN PASSAGE OF THE TROUGH AND LOW THROUGH THE WESTERN GREAT LAKES WEDNESDAY AND WEDNESDAY NIGHT. BETTER FORCING FROM THERMAL ADVECTION PER NAM/GFS 850-700MB Q-VECTOR CONVERGENCE MAXIMA FOLLOWS A FAMILIAR PATTERN OF LATE ACROSS NRN/CENTRAL IA INTO NRN IL...JUST BRUSHING SRN WI...WHICH FOLLOWS ALONG THE NOSE OF THE THERMAL RIDGE AND STRONGEST 850 MB WINDS AS THEY VEER FROM SOUTH TO SOUTHEAST WITH WAVE PASSAGE. HOWEVER CONFIDENT FOR LIKELY POPS EVERYWHERE IN CWA WITH LARGE SALE FORCING FOR ASCENT PROVIDED BY DIFFERENTIAL CVA THAT WORKS ON UNSTABLE AIR MASS...WITH LOW LEVEL FORCING PROVIDED BY LOW TO MID-LAYER FRONTOGENETIC FORCING. FLOODING A CONCERN WITH ANY CONVECTION IN THIS MOISTURE RICH ENVIRONMENT WITH 1.7 TO 1.9 INCH PW/S OR ABOUT 160 PCT OF NORMAL. BEST PERFORMING MODEL QPF FORECASTS BRING AREAL AVERAGE PRECIPITATION OF 1 TO 1.5 INCHES TO THE CWA...BUT ACTUAL AMOUNTS WILL BE MUCH HIGHER WITH ANY MCS THAT MOVES ACROSS CWA. KEPT LIKELY POPS IN THE NORTH WITH BETTER OMEGA AS SFC LOW MOVES THROUGH WEDNESDAY...AND CHANCE POPS EVERYWHERE ELSE...TAPERING OFF WEDNESDAY NIGHT FROM WEST TO EAST BEHIND THE LOW. WITH EXPECTED CONVECTION AND AT LEAST A SIGNIFICANT AMOUNT OF CLOUD DEBRIS WENT WITH BLENDED HIGHS THAT TEND TOWARD THE COOLER SIDE OF GUIDANCE. THURSDAY...FORECAST CONFIDENCE MEDIUM. MODELS DIFFER WITH HOW FAR EAST TO TAKE INITIAL SHORT WAVE TROUGH BY THURSDAY MORNING...BUT ALL SHOW VORTICITY MAXIMA DROPPING THROUGH EASTERN WI AT SOME POINT DURING THE DAY THURSDAY. NAM SOUNDINGS LOOK A BIT TOO GENEROUS WITH SURFACE DEW POINTS...BUT LOW TO MID 80 TEMPS WITH MID-UPPER 60 DEW POINTS STILL YIELD TALL SKINNY SURFACE-BASED CAPE OF AT LEAST 600-800 J/KG...SO WILL HAVE CHANCE THUNDER IN THE EAST...BUT LEAVE WESTERN AREAS DRY. LONG TERM...THURSDAY NIGHT THROUGH MONDAY. FORECAST CONFIDENCE MEDIUM. MODELS CONTINUE TO DIG EASTERN TROUGH THROUGH THE END OF THE WORK WEEK AND DROP A A REINFORCING SHORT WAVE THROUGH THE REGION THAT AIDS IN CLOSING OFF A 500 MB LOW SOMEWHERE OVER THE CENTRAL/EASTERN GREAT LAKES SATURDAY. INSTABILITY WITH THE 500 COLD POOL OVER THE REGION AND VORT MAXES ROTATING THROUGH THE TROUGH WILL KEEP AT LEAST SLIGHT CHANCE POPS IN THROUGH THE EXTENDED...WITH AT OR SLIGHTLY BELOW NORMAL TEMPERATURES INTO NEXT WEEK. AVIATION/00Z TAFS/...CONVECTION ACROSS IOWA TO HAVE GREATEST IMPACT IN FAR SRN WI INTO EARLY EVENING. STRONGEST ACTIVITY LOOKING TO STAY SOUTH OF THE BORDER. THEN SETUP LOOKS SIMILAR TO LAST NIGHT WHERE REDEVELOPMENT BECOMES FOCUSED FURTHER SOUTH. MODEL SOLUTIONS ARE QUITE DIVERGENT ON HOW THE LATE NIGHT CONVECTION PLAYS OUT. BUT IF LAST NIGHT IS ANY INDICATION...SOME TSRA POSSIBLE LATER TONIGHT INTO THE EARLY MORNING HOURS...THEN MORE REDEVELOPMENT DURG TUE AFTN/EVE. OVERALL...VFR WITH POCKETS OF MVFR/ISOLATED IFR IN ANY OF THE HEAVIER STORMS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ046-047-056-057- 062-063-067>069. LM...NONE. && $$ UPDATE...HENTZ TONIGHT/TUESDAY AND AVIATION/MARINE...COLLAR TUESDAY NIGHT THROUGH MONDAY...REM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
642 PM CDT MON JUN 24 2013 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 226 PM CDT MON JUN 24 2013 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE TROUGH MOVING ENE OVER FAR EASTERN SOUTH DAKOTA AND INTO SOUTHWEST MINNESOTA. AREA OF CONVECTION AHEAD OF THIS TROUGH IS DRAWING CLOSER TO THE SW WISCONSIN BORDER. CLOUD COVER OVER CENTRAL AND EAST-CENTRAL WISCONSIN HAS LIMITED HEATING SOMEWHAT TODAY...BUT ML CAPES ARE APPROACHED A 1K J/KG...THOUGH STILL HAVE SOME CIN TO OVERCOME. NOT SURE IF THIS INHIBITION WILL GET OVERCOME...SINCE CLOUDS WILL ONLY THICKEN FROM HERE ON OUT. MOSTLY CLEAR SKIES EXIST BEHIND THIS SHORTWAVE OVER THE CENTRAL PLAINS...AND THE NEXT SHORTWAVE IS MOVING OVER THE CENTRAL ROCKIES. MAIN FORECAST CONCERNS INCLUDE PRECIP CHANCES TONIGHT...AND SEVERE WEATHER CHANCES TOMORROW. TONIGHT...THE SHORTWAVE TROUGH MOVING INTO FAR SOUTHWEST MINNESOTA WILL CONTINUE TO TRACK ENE ACROSS SOUTHERN MINNESOTA AND THE NORTHERN HALF OF WISCONSIN THIS EVENING. CURRENT TRAJECTORY OF PRECIPITATION WILL PLACE THE BEST CHANCES SOUTH OF A TOMAHAWK TO IRON MOUNTAIN LINE. WITH CLOUD COVER KEEPING TEMPERATURES IN THE UPPER 70S TO LOWER 80S OVER CENTRAL AND EAST-CENTRAL WISCONSIN...THE STORMS WILL HAVE SOME CIN TO OVERCOME DESPITE ML CAPES AROUND 1000 J/KG. THINKING SEVERE CHANCES IS RATHER REMOTE SINCE THE NORTHERN END OF THE THUNDERSTORM COMPLEX IS MOSTLY STRATIFORM. PWATS WILL BE INCREASING OVER 1.50 INCHES SO THINKING HEAVY RAINFALL WILL BE THE MAIN THREAT WITH THESE STORMS...BUT EVEN THAT DOES LOOK THAT POSSIBLE. SHOWERS AND STORMS WILL HAVE MOSTLY EXITED THE REGION BY LATE IN THE EVENING...AND THEY SHOULD LAY OUT AN OUTFLOW BOUNDARY OVER SOUTHERN WISCONSIN OR POINTS FURTHER SOUTH. RETURN FLOW WILL REDEVELOP OVER THE NORTHERN PLAINS LATE SO THINKING ANY CONVECTION LATE TONIGHT WILL FALL ALONG THIS OUTFLOW BOUNDARY. HAVE DROPPED POPS SIGNIFICANTLY AFTER MIDNIGHT AND ACROSS NORTHERN WISCONSIN. MUGGY LOWS IN THE MIDDLE 60S. TUESDAY...MUCH OF THE DETAILS IN TOMORROWS WEATHER WILL REVOLVE AROUND WHERE RESULTING OUTFLOW BOUNDARIES END UP AND HOW QUICKLY THE ATMOSPHERE CAN RECOVER. IF THE LAST FEW DAYS ARE ANY INDICATION...IT COULD TAKE UNTIL MID TO LATE AFTERNOON FOR DESTABILIZATION TO OCCUR. BY THIS TIME...RETURN FLOW WILL BE SPREADING NORTHEAST INTO THE REGION AS A SHORTWAVE CURRENTLY OVER COLORADO LIFTS INTO THE NORTHERN MISSISSIPPI VALLEY. DO NOT TRUST MODEL SOUNDINGS MUCH...BUT TEMPS IN THE LOW TO MID 80S AND DEWPOINTS IN THE UPPER 60S SHOULD YIELD AT LEAST 1000 J/KG OF CAPE. 0-6KM BULK SHEAR IS RATHER POOR AROUND 20 KTS...SO WILL BE TOUGH TO GET ANY ORGANIZED CONVECTION. BUT CANNOT RULE OUT AN ISOLATED MENTION IF THE INSTABILITY RECOVERS. HIGHS IN THE LOW TO MID 80S. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 226 PM CDT MON JUN 24 2013 BRIEF PERIOD OF ZONAL FLOW WILL BE ACCOMPANIED BY PRIMARY SHORTWAVE FORECAST TO TRAVERSE THE WESTERN GREAT LAKES DURING THE MIDDLE OF THE WORK WEEK. THERAFTER...THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTIZE PRONOUNCED RIDGING OVER THE WESTERN CONUS WITH DEEPENING DOWNSTREAM TROUGH ACROSS THE GREAT LAKES AND OHIO VALLEY. LOTS OF UNCERTAINTY WITH RESPECT TO THE DETAILS OF EMBEDDED DISTURBANCES WITHIN THE INCREASING NORTHWESTERLY FLOW OVER THE STATE LATE IN THE WORK WEEK. DAILY AVERAGE TEMPERATURES SHOULD REMAIN ABOVE NORMAL...THEN FALL OFF CLOSER TO NORMAL OR PERHAPS A LITTLE BELOW NORMAL BY THE WEEKEND. TUESDAY NIGHT AND WEDNESDAY... PRIMARY FORECAST CHALLENGE EARLY IN THE EXTENDED WILL BE TRYING TO NARROW DOWN THE TIMING AND LOCATION OF CONVECTIVE ACTIVITY ASSOCIATED WITH THE PRIMARY SHORTWAVE DISTURBANCE TUESDAY NIGHT AND WEDNESDAY. FORECAST CONFIDENCE FOR THIS PERIOD IS LOW. NOT GOING TO BUCK TRENDS PAST FEW DAYS AND WILL BET AGAINST QUASISTATIONARY FRONTAL BOUNDARY NEAR THE ILLINOIS-WISCONSIN MAKING MUCH NORTHWARD PROGRESS INTO THE FORECAST AREA TUESDAY NIGHT DESPITE RATHER ROBUST SOUTHWESTERLY LOW-LEVEL FLOW AHEAD OF THE APPROACHING SHORTWAVE. LATEST MODEL TRENDS SEEM TO SUGGEST THAT BULK OF DEEP CONVECTION WILL FIRE ALONG BOUNDARY TO OUR SOUTHWEST AROUND 00Z WEDNESDAY THEN HEAD MORE EASTERLY MAINLY ACROSS THE SOUTHERN THIRD OF THE STATE TUESDAY NIGHT...AS LLJ VEERS WSW BY 12Z WEDNESDAY. WILL TWEAK POPS SOMEWHAT TUESDAY PLACING HIGHEST PROBABALITIES ACROSS THE SOUTHERN THIRD OF THE FORECAST AREA AND TAPERING TO CHANCE ACROSS THE FAR NORTHEAST. IF THIS SCENARIO PLAYS OUT...FEEL BEST COMBINATION OF SHEAR AND INSTABLITY SUPPORTAIVE OF SEVERE STORMS WILL ALSO BE FOCUSED GENERALLY SOUTH OF HIGHWAY 29 TUESDAY NIGHT. PW VALUES FORECAST TO REMAIN QUITE HIGH...NEARLY 2SD ABOVE NORMAL TUESDAY NIGHT...THUS LOCALLY HEAVY RAINFALL IS ALSO THREAT. AS SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW MOVE ACROSS THE FORECAQST AREA WEDNESDAY EXPECT MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY OVER THE ENTIRE FORECAST AREA. AT THIS TIME APPEARS WILL BE CONSIDERABLE CLOUDS AROUND DURING THE DAY ON WEDNESDAY THUS FEEL SEVERE THREAT WILL BE MARGINAL. AGAIN SOME POTENTIAL FOR LOCALLY HEAVY RAINFALL ESPECIALLY OVER THE FOX VALLEY. WILL TREND MAX TEMPS A FEW DEGREES LOWER WEDNESDAY ASSUMING MORE WIDESPREAD PRECIPITATION AND CLOUD COVER. /EB/ THURSDAY INTO THE WEEKEND... LONG RANGE MODELS IN AGREEMENT ON DEVELOPMENT OF HUGE UPPER RIDGE OVER 110 W LATITUDE AND TROF OVER GREAT LAKES. THIS SPELLS A SHOWERY PERIOD WITH TEMPS AOB NORMAL ACROSS REGION FRIDAY INTO MONDAY. BOTH ECMWF AND GFS SHOW SIGNS OF ADDITIONAL ENERGY DIGGING INTO TROF NEXT WEEK...KEEPING THE COOLISH WEATHER AROUND. /JKL/. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 632 PM CDT MON JUN 24 2013 TSTM COMPLEX MOVED THROUGH NORTHERN IL LATE THIS AFTERNOON...WITH ONLY ISOLD SHRA/TSRA OVER CENTRAL/NORTHERN WI. SEEING SOME SIGNS THAT CONVECTION IS SLOWLY INCREASING NEAR THE MN/IA BORDER...AND THIS COULD BE THE START OF ANOTHER CLUSTER OF STORMS WHICH COULD EVENTUALLY PUSH THROUGH CENTRAL/EAST CENTRAL WI OVERNIGHT. THE REMNANTS OF THIS TSTM COMPLEX SHOULD PULL OUT OF THE REGION EARLY TUESDAY...WITH SCT TSTMS POSSIBLY REDEVELOPING LATE IN THE AFTERNOON. HAVE TRENDED TAFS IN THIS DIRECTION...BUT WILL NEED TO WATCH TRENDS OVER THE NEXT COUPLE HOURS TO SEE IF THIS THINKING IS ON TRACK. FOR NOW... HAVE LEFT THE RHI TAF DRY... ALTHOUGH ISOLD SHRA/TSRA MY GET CLOSE EARLY THIS EVENING. DID ADD SOME IFR FOG AT RHI LATE TONIGHT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......JKL AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
614 PM CDT MON JUN 24 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 304 PM CDT MON JUN 24 2013 AT 3 PM...A SQUALL LINE WAS MOVING EAST THROUGH EAST-CENTRAL AND SOUTHEAST IOWA. THIS LINE HAS WIPED OUT MUCH OF THE INSTABILITY THAT MANY OF 24.00Z AND 24.06Z MODELS WERE FORECASTING TO MOVE INTO NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST AND CENTRAL WISCONSIN TONIGHT. EVEN SOME OF THE 24.12Z DETERMINISTIC MODELS WERE NOT HANDLING THIS LINE WELL...SO THEY ARE TOO HIGH ON THEIR CAPES ACROSS IOWA. IN ADDITION...THIS LINE ALSO DISRUPTED THE 925 MB AND 850 MB MOISTURE TRANSPORT INTO THE REGION. AS A RESULT...THE HEAVY RAIN THREAT FOR THIS EVENING LOOKS MUCH LESS THAN WHAT IT WAS LOOKING LIKE EARLIER THIS MORNING. FOR OVERNIGHT...THERE IS A LOT OF UNCERTAINTY ON HOW THIS PERIOD IS GOING TO MATERIALIZE. THE 24.12Z NAM WHICH HAD A SLIGHTLY BETTER HANDLE ON THE SQUALL LINE PUSHED AN OUTFLOW BOUNDARY SOUTH TO THE MISSOURI AND IOWA BORDER...THUS ITS BEST MOISTURE TRANSPORT IS FOCUSED MUCH FURTHER SOUTH. THE 925 MB MOISTURE TRANSPORT HAS SHIFTED TOWARD SOUTHERN IOWA. IF THIS VERIFIES... MUCH OF THE PRECIPITATION WOULD REMAIN SOUTH OF THE AREA FOR THIS TIME PERIOD. EVEN THE LATEST RAP IS LEANING TOWARD THIS SCENARIO TOO. MEANWHILE BOTH THE ECMWF AND GEM MODELS SUGGEST THAT AS THE SHORT WAVE IN THE SOUTHERN PLAINS MOVES NORTHEAST INTO THE SOUTHERN PLAINS...THE 850 MB MOISTURE TRANSPORT SHIFTS BACK NORTHWARD TOWARD THE AREA TOWARD SUNRISE. IF THIS SCENARIO VERIFIES...THERE COULD BE A POTENTIAL FOR THE REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS LATE TONIGHT. WITH ITS PRECIPTABLE WATER VALUE CLOSE TO 2.00 INCHES AND WARM CLOUD LAYER DEPTHS UP TO 4.5 KM...THERE WOULD BE THE POTENTIAL FOR HEAVY RAIN. WITH SO MANY DIVERSE MODEL SOLUTIONS...OPTED TO LOWER THE PRECIPITATION CHANCES SOME AND ALSO SHIFTED THE HIGHER CHANCES TO LATER IN THE NIGHT. HOPEFULLY...THE 24.00Z MODELS WILL BE BETTER AT RESOLVING THE STABLE LAYER THAT WAS LEFT IN THE WAKE OF THE SQUALL LINE. ON TUESDAY...EXPECT THE 925 MB AND 850 MB MOISTURE TRANSPORT TO INCREASE ACROSS IOWA. HOWEVER THERE IS SOME UNCERTAINTY HOW FAR NORTH THIS OCCUR. THE 24.18Z NAM AND 24.12Z GFS WOULD SUGGEST THAT THE HEAVIEST RAIN WOULD FALL ACROSS CENTRAL IOWA. MEANWHILE THE 24.12Z ECMWF AND GEM WOULD SUGGEST THAT THE HEAVIEST RAIN WOULD FALL SOUTH OF INTERSTATE 90. WITH THE INITIAL CONDITIONS SO MUDDLED...CONFIDENCE IS NOT THAT HIGH. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 304 PM CDT MON JUN 24 2013 ON TUESDAY NIGHT...MUCH OF THIS TIME PERIOD REMAINS UNCLEAR DUE TO UNCERTAINTIES ON WHERE THE BOUNDARIES WILL END UP FROM TONIGHT AND WHERE THUNDERSTORMS DEVELOP ON TUESDAY. THE GEM AND ECMWF HAVE THEIR MESOSCALE CONVECTIVE COMPLEXES MOVING ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR. MEANWHILE THE GFS AND NAM SUGGEST THAT THE MESOSCALE CONVECTIVE COMPLEX WILL DEVELOP ACROSS IOWA...AND THEN MOVES IT NORTHEAST WITH THE SHORT WAVE INTO THE FORECAST AREA. WITH WARM CLOUD LAYER DEPTHS OVER 4 KM AND PRECIPITABLE WATER VALUES AROUND 2 INCHES. THERE WILL BE THE POTENTIAL FOR SOME FLASH FLOODING. ON WEDNESDAY AND WEDNESDAY EVENING...ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA AS THE LOW PRESSURE AREA MOVES EAST ACROSS THE AREA. PRECIPITABLE WATER VALUES SLOWLY DROP TO AROUND 1.60 INCHES AND THE WARM CLOUD LAYER DEPTHS FALL INTO THE 3 TO 3.5 KM RANGE. WHILE THERE WILL BE THE POTENTIAL FOR SOME HEAVY RAIN...THE AMOUNTS LOOK TO BE MUCH LESS THAN WHAT THEY ARE FROM TONIGHT INTO TUESDAY NIGHT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 614 PM CDT MON JUN 24 2013 LINGERING BAND OF LIGHT SHOWERS REMAINS IN THE I90 CORRIDOR LATE THIS AFTERNOON. RADAR SHOWS A SLOW EAST/SOUTHEAST MOVEMENT WITH SOME DECREASE IN THE REFLECTIVITY BUT WILL CONTINUE TO CARRY A VCSH WITH VFR CONDITIONS THROUGH THE MIDDLE OF THE EVENING. FOR LATER TONIGHT...THE MAIN SYNOPTIC BOUNDARY REMAINS OVER NORTHERN MISSOURI AND AS THE LOW LEVEL JET INTERSECTS THIS...ANOTHER ROUND OF STORMS SHOULD DEVELOP AND THEN MOVE OFF TO THE EAST/NORTHEAST. WOULD TEND TO THINK THESE WOULD STAY SOUTH OF THE TAF SITES AS THE BOUNDARY IS EVEN A LITTLE FARTHER SOUTH THAN THIS TIME SUNDAY. THE 24.20Z HRRR DOES SHOW A LINE DEVELOPING LATE TONIGHT AND MOVING INTO THE AREA...BUT AT THE SAME TIME...IT IS LIFTING THE BOUNDARY INTO CENTRAL IOWA AND NOT SURE HOW PLAUSIBLE OF AN OUTCOME THAT IS. WITH LIKELY RAIN CHANCES IN THE GRIDDED DATA BASE FOR LATE TONIGHT WILL HONOR THE HRRR SOLUTION AND SHOW VCTS FOR BOTH SITES LATE TONIGHT BUT OTHERWISE MAINTAIN VFR CONDITIONS. CONFIDENCE FOR TUESDAY AFTERNOON IS ALSO LOW AS THERE SHOULD BE ADDITIONAL DEVELOPMENT ALONG AND NORTH OF THE BOUNDARY AS A PRETTY STRONG SHORT WAVE TROUGH COMES INTO THE AREA. WHERE THIS WILL OCCUR ALL DEPENDS ON THE POSITION OF THE BOUNDARY AND TOO MUCH UNCERTAINTY ON THIS RIGHT NOW TO EVEN INCLUDE A VCTS FOR THE AFTERNOON. IF THE BOUNDARY DOES MOVE NORTH...THUNDERSTORMS WILL HAVE TO BE INCLUDED WITH LATER FORECASTS. && .HYDROLOGY... ISSUED AT 304 PM CDT MON JUN 24 2013 WITH A WIDE VARIETY OF SOLUTIONS IN THE 24.12Z AND 24.18Z MODELS...CONFIDENCE HAS LOWERED ON THE THREAT FOR FLASH FLOODING TONIGHT. HOWEVER WITH MANY RIVERS REMAINING EITHER HIGH OR ARE FLOODING ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. CONFIDENCE WAS NOT HIGH ENOUGH TO CANCEL THE FLASH FLOOD WATCH. LOOKING AHEAD TO TUESDAY AND TUESDAY NIGHT...SOME MODELS SUGGEST THAT HEAVY RAIN COULD FALL SOUTH OF INTERSTATE 94. MEANWHILE OTHER MODELS HINT THAT THE HEAVIEST PRECIPITATION WILL REMAIN SOUTH OF THE FORECAST AREA. WITH SUCH DIVERSE SPREADS IN THE MODELS...OPTED NOT TO EXTEND THE FLASH FLOOD WATCH INTO TUESDAY NIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ032>034-041>044- 053>055-061. MN...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR MNZ079-086>088- 094>096. IA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR IAZ008>011-018-019- 029-030. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...04 HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
344 PM CDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 344 PM CDT SUN JUN 23 2013 AT 3 PM...A LINE OF SHOWERS AND THUNDERSTORMS WAS MOVING ACROSS NORTHERN ILLINOIS. MEANWHILE THERE WAS ANOTHER CONVERGENT BOUNDARY ALONG THE MISSISSIPPI RIVER. BOTH THE 23.12Z ARW AND NMM DEVELOP A LINE OF THE SHOWERS AND THUNDERSTORMS ALONG THE LATTER BOUNDARY BETWEEN 23.21Z AND 24.00Z. HOWEVER THEY ALSO HAVE AROUND 3000 J/KG OF SURFACE BASED CAPE AND THE SPC SURFACE BASED CAPE IS CURRENTLY ONLY AROUND 500 J/KG...SO THINKING THAT THE AREA WILL REMAIN DRY FOR LATE THIS AFTERNOON LIKE THE LAST 3 HOURLY RUNS OF THE HRRR HAVE BEEN SHOWING. FOR THIS EVENING...THE 23.12Z MESO /RAP...NMM...AND ARW/ AND DETERMINISTIC MODELS SUGGEST THAT THE COMBINATION OF MODERATE 850 MB MOISTURE TRANSPORT AND 2 TO 3K MOST UNSTABLE CAPES WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS NORTHEAST IOWA...AND CENTRAL AND SOUTHWEST WISCONSIN. THE HRRR WAS SUGGESTING A SIMILAR SCENARIO EARLIER THIS MORNING AND HAS SINCE BACKED AWAY FROM THIS SOLUTION. WITH THERE BEING SUCH AGREEMENT IN THE MODELS OPTED TO KEEP A 20 TO 60 PERCENT CHANCE GOING FOR THIS AREA TONIGHT. WITH LITTLE OR NO PRECIPITATION EXPECTED ELSEWHERE ACROSS THE FORECAST AREA...WILL DROP THE FLASH FLOOD WATCH ACROSS SOUTHEAST MINNESOTA AND PARTS OF WEST CENTRAL WISCONSIN. FOR OVERNIGHT...BOTH THE ECMWF AND NOW THE HRRR SHOW THAT A SHORT WAVE CURRENTLY OVER THE TEXAS PANHANDLE WILL MOVE NORTHEAST INTO NORTHEAST IOWA AND SOUTHWEST WISCONSIN. THE HRRR SHOWS AN AREA OF SHOWERS AND THUNDERSTORMS SURGING NORTHWARD TOWARD THE FORECAST AREA AFTER 07Z. DUE TO THIS KEPT...THE PRECIPITATION CHANCES IN THE 20 TO 60 PERCENT RANGE. WITH PRECIPITABLE WATER VALUES AROUND 1.8 INCHES AND WARM CLOUD LAYER DEPTHS UP 4.5 KM...THESE THUNDERSTORMS WILL BE VERY EFFICIENT RAIN PRODUCERS...THUS...KEPT THE FLASH FLOOD WATCH UP NORTHEAST IOWA AND SOUTHWEST AND CENTRAL WISCONSIN. THE ONLY QUESTION IN THE FORECAST IS WHETHER WE HAVE THE PRECIPITATION CHANCES DECREASING TOO FAST TOWARD SUNRISE. ON MONDAY...THERE IS UNCERTAINTY ON HOW LONG THE SHORT WAVE WILL LINGER ACROSS SOUTHWEST WISCONSIN AND NORTHEAST IOWA. WITH MANY OF THE MESO MODELS DRY FOR THE MORNING...DECIDED TO TREND THE PRECIPITATION CHANCES TOWARD THE DRY SIDE. DURING THE AFTERNOON...THERE IS UNCERTAINTY ON HOW FAST THE 850 MB MOISTURE TRANSPORT WILL DEVELOP ACROSS THE AREA. THE NAM HAS IT DEVELOPING DURING THE LATE AFTERNOON AND MANY OF THE OTHER MODELS SUGGEST THAT IT MIGHT OCCUR ON MONDAY NIGHT. WITH THERE BEING VERY LITTLE CONSISTENCY IN THE MODELS OVER THE PAST SEVERAL DAYS...DECIDED TO COMPROMISE WITH 30 TO 40 PERCENT PRECIPITATION PROBABILITIES. LIKE OVER THE WEEKEND...THE 0-6 KM SHEAR REMAINS LESS THAN 40 KNOTS. HOWEVER THE 0-3KM CONTINUES ABOVE 30 KNOTS...THUS COULD SEE THE POTENTIAL FOR SOME BOWING SEGMENTS AS THE THUNDERSTORMS BECOME COLD POOL DOMINANT. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 344 PM CDT SUN JUN 23 2013 ON MONDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT A MESOSCALE CONVECTIVE COMPLEX WILL DEVELOP JUST WEST OF THE FORECAST AREA AND THEN MOVE THROUGH THE FORECAST AREA DURING THE NIGHT. WITH STRONG 850 MB MOISTURE TRANSPORT AND ISENTROPIC LIFT INTO THE REGION... PRECIPITABLE WATER VALUES RUNNING AROUND 2 INCHES...AND WARM CLOUD DEPTHS EXCEEDING 4 KM...EXPECT AN AREA OF HEAVY RAIN /POTENTIALLY 3 TO 5 INCHES/ TO FALL ACROSS PARTS OF THE FORECAST AREA. MANY OF THE MODELS ARE SUGGESTING ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. HOWEVER WITH THE MODELS BEING A BIT TOO FAR NORTH LATELY...THERE IS A POSSIBILITY THAT THE HEAVIEST PRECIPITATION MAY FALL ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. WILL LIKELY HAVE TO ISSUE ANOTHER FLASH FLOOD WATCH FOR THIS TIME PERIOD EITHER LATE TONIGHT OR ON MONDAY. FROM TUESDAY AFTERNOON INTO TUESDAY NIGHT...THE MODELS SHOW YET ANOTHER MESOSCALE CONVECTIVE COMPLEX MOVING THROUGH THE REGION. WITH THE MODELS CONTINUING TO SHOW STRONG 850 MB MOISTURE TRANSPORT AND ISENTROPIC LIFT INTO THE REGION... PRECIPITABLE WATER VALUES RUNNING AROUND 2 INCHES...AND WARM CLOUD DEPTHS EXCEEDING 4 KM...EXPECT AN AREA OF HEAVY RAIN /POTENTIALLY ANOTHER 3 TO 5 INCHES/ TO FALL ACROSS PARTS OF THE FORECAST AREA. AT THIS TIME... IT LOOKS LIKE THE HEAVIEST RAIN WOULD FALL ALONG AND SOUTH OF THE INTERSTATE 90 CORRIDOR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1230 PM CDT SUN JUN 23 2013 TSRA SHOULD REMAIN SOUTH OF THE TAF SITES THROUGH THE PERIOD. HAVE REMOVED THE TSRA CHANCES IN THE TAFS...BUT WILL KEEP A CLOSE EYE ON ADDING THESE BACK. IT APPEARS A VFR PERIOD IS WARRANTED. && .HYDROLOGY... ISSUED AT 344 PM CDT SUN JUN 23 2013 WITH SLIGHTLY DRIER AIR MOVING INTO SOUTHEAST MINNESOTA AND WEST- CENTRAL WISCONSIN THIS AFTERNOON...THE THREAT FOR HEAVY RAIN HAS GREATLY DIMINISHED ACROSS MUCH OF SOUTHEAST MINNESOTA AND PARTS OF WEST CENTRAL WISCONSIN. AS A RESULT...DROPPED THE FLASH FLOOD WATCH IN THESE AREAS. MEANWHILE IN SOUTHWEST AND CENTRAL WISCONSIN AND NORTHEAST IOWA...THERE WILL BE THE POTENTIAL FOR THE DEVELOPMENT OF THUNDERSTORMS ACROSS THESE AREAS FROM LATE EVENING INTO THE OVERNIGHT. CONDITIONS CONTINUE TO BE FAVORABLE FOR THE THUNDERSTORMS TO EFFICIENT RAIN PRODUCERS. RAINFALL AMOUNTS TONIGHT COULD RANGE FROM 0.50 TO 1.50 INCHES. SINCE THESE AREAS HAVE SEEN ANYWHERE FROM 6 TO 10 INCHES DURING THE LAST 3 DAYS...IT WILL NOT TAKE MUCH WATER TO PRODUCE FLASH FLOODING. ADDITION FLASH FLOODING LOOKS LIKELY ACROSS PARTS OF THE FORECAST AREA ON MONDAY NIGHT AND FROM TUESDAY AFTERNOON INTO TUESDAY NIGHT. EACH OF THESE EVENTS COULD PRODUCE 3 TO 5 INCHES OF RAIN ACROSS THE AREA. HOWEVER THERE CONTINUES TO BE MUCH UNCERTAINTY ON WHERE THIS RAIN MAY FALL. EXPECT ADDITIONAL FLASH FLOOD WATCHES TO BE ISSUED FOR THESE TIME PERIODS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH MONDAY MORNING FOR WIZ041>044-053>055- 061. MN...FLASH FLOOD WATCH THROUGH MONDAY MORNING FOR MNZ096. IA...FLASH FLOOD WATCH THROUGH MONDAY MORNING FOR IAZ008>011-018-019- 029-030. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...BAUMGARDT HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
341 PM CDT SUN JUN 23 2013 .VERY SHORT TERM...TONIGHT AND MONDAY. TONIGHT - CONFIDENCE...LOW SURFACE/UPPER LOW LIFTING NORTH FROM NORTH DAKOTA. ONGOING CONVECTION DRIVEN BY OUTFLOW AHEAD OF DECAYING IOWA COMPLEX. NICE LINE MAINLY SOUTH OF THE BORDER WILL SHIFT EAST LATE THIS AFTERNOON SETTING UP A DRY EVENING FOR A WHILE. TRENDS IN HRRR SUGGEST ACTIVITY WILL RE-FIRE LATER TONIGHT WITH ARRIVAL OF A RENEWED 850 MILLIBAR JET LET. HOWEVER NOW LATCHING ONTO THE MISSOURI COMPLEX THIS RENEWED DEVELOPMENT SKEWED FURTHER SOUTHWEST INTO IOWA. THE 12Z SPC 4KM WRF ALSO SHOWS POTENTIAL FOR REDEVELOPMENT WITH THE 850 JET...AND WOULD FAVOR A MORE NORTHERN SOLUTION. IN ADDITION MODELS SHOW SOME DIVERGENCE WITH RIGHT REAR QUADRANT OF 250-300 MILLIBAR JET MAX TRAVERSING THE NORTHERN LAKES. REALLY CONCERNED THAT MISSOURI COMPLEX MAY STEAL OUR THUNDER BY DISRUPTING RETURN OOMPH OF LLJ THIS FAR NORTH. WILL HAVE TO WAIT AND SEE ON THIS. AFTER COLLABORATING WITH NEIGHBORS CONSENSUS IS TO HOLD ON TO THE WATCH. MODEL TRENDS NOT SUGGESTING TRAINING TYPE REDEVELOPMENT SHOULD IT OCCUR...BUT RATHER SCATTERED TYPE SHRA/TSRA...AND IT MAY ARRIVE VERY LATE. GIVEN THE HEAVY AMOUNT OF RAIN THAT HAS ALREADY FALLEN IN THE WATCH AREA WE WON/T NEED A TEXTBOOK FLASH FLOOD SETUP TO LEAD TO POSSIBLE ISSUES WITH FLOODING. SO WILL HANG ONTO THE WATCH FOR NOW...BUT GIVEN MODEL VARIATION WITH WHERE LATER DEVELOPMENT OCCURS CONFIDENCE IN CONVECTIVE TRENDS NOT THE GREATEST. MONDAY - CONFIDENCE...LOW TO MEDIUM SOME SUGGESTION THAT THE MORNING 850 JET PEELS OFF AND SETS UP A LULL IN CONVECTION WITH WEAK RIDGING. GFS AND ECMWF SHOW REDEVELOPMENT ACROSS THE CWA DURING THE AFTERNOON WHILE THE NAM AND GEM SHOW A DRIER LOOK. THE GFS IS SHOWING A FAIRLY SIGNIFICANT SURGE IN THE 850 JET DURING THE AFTERNOON WHILE OTHER MODELS SUGGEST FOCUS WILL BE FURTHER WEST. PLENTY OF MOISTURE AVAILABLE SO KEEPING THE FLASH FLOOD WATCH IN PLACE SEEMS THE BEST WAY TO GO AT THIS POINT. .SHORT TERM...MONDAY NIGHT THROUGH WEDNESDAY. FORECAST CONFIDENCE LOW TO MEDIUM. WEAK RIDGING BETWEEN ONTARIO SHORT WAVE PUSHING TO THE EAST AND AHEAD OF NEXT SHORT WAVE CROSSING THE NORTHERN INTERMOUNTAIN REGION INTO THE NORTHERN PLAINS THAT REACHES WESTERN GREAT LAKES BY WEDNESDAY MORNING. COULD BE ONGOING CONVECTION MONDAY EVENING WITH 850 MB WAA/MOISTURE ADVECTION AND WEAK PERTURBATIONS/MCVS THAT ALL MODELS SHOW AT DIFFERING TIMES/STRENGTHS FROM MONDAY NIGHT INTO TUESDAY. GFS LOOKS OVERDONE WITH DEEP LAYER MESOLOW CROSSING CENTRAL WI DURING THE OVERNIGHT AND WILL BE IGNORED. BEST CHANCES FOR SEEING AN MCS IS WESTERN CWA AS IT MAY TRACK WITH LOW-LEVEL JET AS IT FOCUSES ON SW WI AS IT VEERS FROM SOUTH TO SOUTHWEST AROUND 06Z. LIKELY POPS IN THE WEST TAPERING TO CHANCE IN THE EAST. WHILE PW/S NOT AS ROBUST AS THE PAST FEW DAYS...STILL 1.3 INCHES TO 1.5 INCHES OR AROUND 135% OF NORMAL. WILL HAVE TO CONTINUE TO WATCH SATURATED WESTERN CWA FOR FLASH FLOODING POTENTIAL. WITH LEE SURFACE CYCLOGENESIS OVER THE PLAINS AHEAD OF SHORT WAVE TROUGH AND BROAD AREA OF HIGH PRESSURE OVER THE SE U.S. REGION REMAINS IN THE WARM SECTOR ON SOUTHEASTERN SIDE OF FAIRLY STATIONARY SURFACE TROUGH WITH A STEADY SSW FEED OF MOIST UNSTABLE AIR INTO THE REGION. NEXT LOW-LEVEL JET MAX APPROACHES TUE EVENING...WITH 12Z NAM TAKING DEAD AIM AT SRN WI WHILE GFS MORE SRLY AND FOCUSED ON MN/IA THEN VEERING TOWARD WI OVERNIGHT AND WEAKENING. WILL HAVE LIKELY POPS EVERYWHERE TUESDAY NIGHT...WITH CHANCE POPS WEDNESDAY AS TROUGH MOVES THROUGH. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY. FORECAST CONFIDENCE MEDIUM. EVOLUTION FROM NEAR-ZONAL FLOW TO A MORE AMPLIFIED PATTERN BEGINS AS WEDNESDAY SHORT WAVE TROUGH IS FOLLOWED BY A DIGGING TROUGH THAT DROPS INTO THE UPPER GREAT LAKES. GFS MUCH DEEPER AND COLDER THAN ECMWF. STREAM OF VORTICITY MAXIMA THROUGH THE REGION KEEPS CHANCE POPS IN THE FORECAST DURING THIS TRANSITION. UPPER GREAT LAKES WILL BE IN NW FLOW BETWEEN THE DEEPENING ERN U.S. TROUGH AND A BROAD AMPLIFYING RIDGE OVER THE WEST BRINGING COOLER TEMPERATURES CLOSER TO NORMAL FOR THE END OF THE WEEK INTO THE WEEKEND. && .AVIATION/00Z TAFS/...LINE OF CONVECTION FROM EXTREME SRN WI INTO IL WILL SHIFT EAST OF THE TAF SITES LATE THIS AFTN. EXPECTING LATE NIGHT REDEVELOPMENT WITH 850 MILLIBAR JET BEING THE PRIMARY FOCUS. THIS ACTIVITY PROGGD TO AFFECT THE AREA INTO MONDAY MORNING WITH PERHAPS A LULL DEVELOPING LATE MORNING INTO EARLY AFTERNOON. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH MONDAY EVENING FOR WIZ046-047-056-057- 062-063-067>069. LM...NONE. && $$ TONIGHT/MONDAY AND AVIATION/MARINE...COLLAR MONDAY NIGHT THROUGH SUNDAY...REM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND MONDAY ISSUED AT 252 PM CDT SUN JUN 23 2013 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SURFACE WARM FRONT HAS MOVED THROUGH MOST OF WISCONSIN EXCEPT FOR FAR NORTHEAST WISCONSIN EARLY THIS AFTERNOON. SOME REMNANT STORMS FROM AN EARLIER LINE OF CONVECTION ARE MOVING ACROSS SOUTHERN WISCONSIN...BUT STARTING TO SEE SIGNS OF BEEFY CU DEVELOPING FARTHER NORTH FROM WAUSHARA COUNTY TO THE WESTERN UPPER PENINSULA. THIS IS IN A REGION OF BUILDING ML CAPES FROM 1000-1400 J/KG. STILL PLENTY OF TIME FOR FURTHER DESTABILIZATION TO OCCUR...WITH LIFT VIA SHORTWAVE OVER NORTHWEST WISCONSIN. AM STILL EXPECTING STORMS TO FIRE THOUGH IT MAY STILL HAVE A COUPLE HOURS TO GO. ACTUAL FRONT LIES ACROSS EASTERN MINNESOTA AND CLEARING SKIES ARE MOVING INTO SOUTHWEST MINNESOTA. IMPACTS FROM CONVECTION ARE THE MAIN FORECAST CONCERN IN THE SHORT TERM. TONIGHT..SHORTWAVE OVER NORTHWEST WISCONSIN WILL LIFT NORTHEAST AND CLEAR NORTHEAST WISCONSIN IN THE EVENING. FORCING ALONG THE TAIL OF THIS VORT AND FURTHER DESTABILIZATION SHOULD ALLOW SCT STORMS TO MOVE ACROSS NORTHEAST WISCONSIN IN THE EVENING. WINDS AT 700MB ARE PRETTY STRONG AT 45 TO 50 KTS...SO ANY STORMS WILL HAVE POTENTIAL AT CREATING DAMAGING WIND GUSTS AND SMALL HAIL. LOSS OF HEATING AND EXITING OF THE TAIL OF THE VORT SHOULD LET THE CONVECTION DIMINISH AND/OR EXIT BY MID TO LATE EVENING. ACTUAL SURFACE FRONT WILL DROP INTO NORTH-CENTRAL WISCONSIN AFTER MIDNIGHT. CONVERGENCE ALONG THE FRONT IS VERY WEAK AND THERE IS NO SUPPORT ALOFT...SO COULD SEE SOME LOW CLOUDS ALONG THE FRONT...MUCH NOT MUCH ELSE. WILL END POPS FROM NW TO SE AFTER MIDNIGHT. MUGGY LOWS IN THE MID TO UPPER 60S. MONDAY...SURFACE FRONT WILL STALL ACROSS NORTHERN WISCONSIN IN THE MORNING. PROGGED SOUNDINGS AND UPSTREAM SATELLITE IMAGERY SHOW PLENTY OF DRY AIR THROUGH THE COLUMN AND PARTLY TO MOSTLY CLEAR SKIES. NO CLEAR TRIGGERS UPSTREAM EITHER SO WILL GO WITH A DRY BUT PARTLY CLOUDY START TO THE DAY. COME AFTERNOON...AN 86/69 PARCEL OVER THE FOX VALLEY WILL RESULT IN 3000 J/KG OF ML CAPE AND VERY LITTLE CIN. CONVECTIVE TEMPS ARE IN THE LOW 90S AND DO NOT SEE A TRIGGER...BUT PERHAPS THE LAKE BREEZE CAN CREATE THE NECESSARY CONVERGENCE FOR A STORM OR TWO TO POP. WILL KEEP A SLIGHT CHANCE OF A STORM OVER CENTRAL AND NORTHEAST WISCONSIN WHERE INSTABILITY IS MAXIMIZED. HIGHS MAINLY IN THE MID 80S. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 252 PM CDT SUN JUN 23 2013 MEDIUM RANGE MODELS ARE IN GREATER DISAGREEMENT THAN THE LAST FEW DAYS...ESPECIALLY WITH A POSSIBLE CONVECTIVE COMPLEX LATE MONDAY NIGHT OR TUESDAY AND AGAIN WEDNESDAY NIGHT WITH THE POSSIBLE FORMATION OF A CLOSED LOW OVER WISCONSIN OR UPPER MICHIGAN. AS FAR AS LATE MONDAY NIGHT AND TUESDAY GOES IT LOOKS LIKE THE GFS IS EXHIBITING SOME SORT OF CONVECTIVE FEEDBACK PRODUCING A CLOSED UPPER LOW THAT MOVES ACROSS MINNESOTA AND WISCONSIN PRODUCING CONSIDERABLE CONVECTION. THIS IS LIKELY OVERDONE AND PREFER THE FLATTER AND SLOWER UPPER SYSTEM THAT SHOULD BRING SHOWERS AND THUNDERSTORMS TUESDAY AFTERNOON AND EVENING. THE GFS ALSO FORECASTS A CLOSED UPPER LOW WEDNESDAY NIGHT AND THURSDAY OVER THE WESTERN GREAT LAKES WHICH SEEMS OVERDONE CONSIDERING THE CURRENT PATTERN. CANNOT TOTALLY DISCOUNT THE GFS AS IT HAS SOME SUPPORT FROM THE NAM BUT THE ECMWF IS MUCH FASTER AND WEAKER. WARM AND HUMID WEATHER EXPECTED THROUGH THURSDAY. AFTER THURSDAY THE MODELS DO AGREE THAT AN UPPER RIDGE WILL DEVELOP OVER THE WESTERN UNITED STATES WITH CYCLONIC NORTHWEST FLOW OVER WISCONSIN. THIS SHOULD BRING COOLER AND DRIER AIR TO THE REGION BY FRIDAY AND SATURDAY. WHILE IT SHOULD BE GENERALLY DRY FRIDAY AND SATURDAY THERE COULD BE SCATTERED DIURNAL SHOWERS WITH COLD TEMPERATURES ALOFT. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1240 PM CDT SUN JUN 23 2013 A WEAK FRONT WILL PASS ACROSS THE REGION THIS AFTERNOON. WITH CONTINUED HEATING...STORMS SHOULD REDEVELOP ALONG THIS FRONT...THOUGH EXACT TIMING/IMPACT IS STILL UNCERTAIN. INSTABILITY HAS BEEN SLOW TO BUILD THIS MORNING...SO THINKING THIS MAY BE A MID TO LATE AFTERNOON THING...WHICH COULD ENTIRELY MISS THE CENTRAL AND NORTH-CENTRAL WISCONSIN TAF SITES. DUE TO THE UNCERTAINTY...WILL LEAVE ANY MENTION OF THUNDER OUT OF THOSE TAF SITES. BETTER CHANCES APPEAR TO OCCUR OVER THE FOX VALLEY AND LAKE SHORE LATE THIS AFTERNOON...SO HAVE ADDED A TEMPO GROUP. BEHIND THE FRONT...MVFR CLOUD DECK WILL LIKELY IMPACT N-C WISCONSIN TONIGHT. VSBYS TO ALL FALL INTO THE MVFR RANGE LATE TONIGHT WITH THE HUMID AIRMASS IN PLACE. LOOKING LIKE GOOD FLYING WEATHER TOMORROW AT THE MOMENT. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1048 AM CDT SUN JUN 23 2013 .UPDATE...NO CHANGES PLANNED TO FFA AT THIS TIME. SURFACE/UPPER LOW LIFTING NORTH FROM NORTH DAKOTA. MEANWHILE CONVECTION ACROSS IA HAS SHOWN A WEAKENING TREND...ESPECIALLY IN NRN IA. PLENTY OF INSTABILITY IN THE CLEAR AIR ACROSS SRN WI. HRRR SUGGESTS ACTIVITY INCREASES A BIT ON OUTFLOW AHEAD OF THE WEAKENING CONVECTIVE SYSTEM AS IT HEADS INTO WI EARLY/MID AFTERNOON. 850 JET LIFTS NORTH DURING THE AFTERNOON WITH BETTER 500 FORCING ALSO TO OUR NORTHWEST. SO WILL RELAY ON LOW LEVEL OUTFLOW OR CONVECTIVE INDUCED VORT MAX FOR FORCING MECHANISM THIS AFTERNOON. ARRIVAL OF SOUTHWEST 850 JET TONIGHT RENEWS THREAT FOR ADDITIONAL CONVECTIVE DEVELOPMENT AND FLASH FLOOD THREAT. PC && .AVIATION/18Z TAFS/...ONGOING CONVECTION ACRS IA SHOWING WEAKENING. HOWEVER AIRMASS ACROSS SRN WI UNSTABLE. POTENTIAL FOR ONGOING PRECIP BAND TO REINTENSIFY OR AS MESO MODELS SUGGEST...DEVELOPMENT ALONG OUTFLOW BOUNDARY THIS AFTERNOON. ADDITIONAL TSRA LIKELY OVERNIGHT AS 850 LOW LEVEL JET BECOMES BETTER ORIENTED TOWARDS SRN WI. PC && .PREV DISCUSSION... /ISSUED 321 AM CDT SUN JUN 23 2013/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM. HIGH RESOLUTION MODELS HAVE HAD A GOOD HANDLE ON THE RAPID DECAY OF MCS OVERNIGHT. ONE ACTIVE AREA OF STORMS MOVING ALONG THE MISSISSIPPI RIVER TOWARD SOUTHWEST WISCONSIN BUT EVEN THIS HAS SHOWN DOWNWARD TREND AND SHOULD BE GONE BEFORE 12Z. OUTFLOW BOUNDARY PUSHED SOUTH INTO NORTHERN ILLINOIS AND WE MAY HAVE AN ISSUE AGAIN WITH HIGH TEMPERATURES DUE TO DEBRIS CLOUDS AND LOW LEVEL COLD POOL. BUT THERE SHOULD BE MORE SUN AND WARMER HIGHS AND TDS AROUND 70F SHOULD MAKE IT FEEL PRETTY MUGGY. LOW LEVEL JET WEAKENS AND SHIFTS WEST FOR A TIME TODAY SO IT LOOKS LIKE A PRETTY QUIET MORNING AND EARLY AFTERNOON. BOTH GFS AND NAM HAVE A DRY POCKET MOVING ACROSS SOUTHERN WISCONSIN TODAY AND THERE IS SUBTLE EVIDENCE OF THAT ON SATELLITE CURRENTLY. THEN LOW LEVEL POSITIVE THETA-E ADVECTION KICKS IN LATE THIS AFTERNOON IN THE WEST AND TONIGHT ACROSS MOST OF THE AREA AS SHORT WAVE TROUGH BRUSHES AREA TO THE NORTH AND LOW LEVEL JET LEANS OVER AGAIN. PATTERN OF WEAK UPPER TROUGHS TOPPING RIDGE AXIS WITH AN EAST-WEST OUTFLOW BOUNDARY TO FOCUS CONVECTION HAS THIS LOOKING MUCH LIKE SERIES OF MADDOX MESOHIGH TYPE FLASH FLOOD EVENTS. NAM AND GFS SHOW PRECIPITABLE WATER INCREASING TO 150-175% OF NORMAL WITH VALUES OF 1.7 TO 2.0". CORFIDI VECTORS HAVE THE OMINOUS LIGHT AND VARIABLE LOOK AS THEY HAVE PAST COUPLE OF DAYS SO HEAVY RAIN THREAT SEEMS TO CONTINUE. ALTHOUGH THE MODELS HAVE THE LOOK OF A FAST MOVING LINE OF STORMS...WIDESPREAD 4-8" RAINFALL OVER THE WEST THE PAST COUPLE OF DAYS AND ONGOING FLOODING CALLS FOR A FLASH FLOOD WATCH FROM THIS AFTERNOON INTO TONIGHT. PER COORDINATION WITH ARX AND DVN WILL START THIS IN THE MIDDLE AFTERNOON AND THEN RUN IT THROUGH TONIGHT AND MONDAY AS THE BOUNDARY STALLS AND THE LOW LEVEL JET SITS OVER THE AREA WITH HIGH MOISTURE AND INSTABILITY. ADJUSTED THE QPF UP A BIT TONIGHT AND MONDAY ABOVE GUIDANCE IN THE WESTERN HALF THOUGH CONFIDENCE ON WHERE TO PUT HIGHEST AMOUNTS AND HOW HIGH TO GO BUT LOCALLY 1-2" PER 12 HOURS SEEMS PLAUSIBLE. WITH 1 HOUR FFG ONLY 1 TO 1.5" IN THE WEST WE WILL REMAIN VULNERABLE FOR SEVERAL DAYS TO FLASH FLOODING IN THE HILLY TERRAIN OF SOUTH CENTRAL WISCONSIN. MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE MEDIUM. CONVECTION POTENTIAL AND MODEL TIMING/FEATURE DIFFERENCES CONTRIBUTE TO THE UNCERTAINTY THIS FCST PERIOD. MODELS GENERALLY FORECAST A SHORT WAVE TROUGH AND VORT MAX TO BEGIN TRAVERSING THE CWA MONDAY AFTERNOON. THE THERMODYNAMIC ENVIRONMENT WILL BE ON ITS WAY TO BEING PRIMED AS SEEN BY STEEPENING MID-LEVEL LAPSE RATES AND SYNOPTIC ASCENT THAT IS PRESENT WITH Q-VECTOR DIVG AND LOW-LEVEL WAA OCCURRING. HOWEVER...THE PRIMARY CONCERN LOOKS TO BE TIED TO THE PRESENCE OF OR LACK OF LIFT/FOCUS...BE IT A RESIDUAL OUTFLOW BOUNDARY OR SFC BOUNDARY. OTHERWISE AMPLE INSTABILITY IN EITHER MEAN LAYER OR MOST UNSTABLE CAPE WILL COMBINE WITH SUFFICIENT MOISTURE...WITH SFC DEW POINTS FCST IN THE UPPER 60S-LOW 70S. DEEP LAYER 0-6 KM SHEAR COULD BE THE LIMITING FACTOR WITH ANY DEVELOPMENT MONDAY BUT IT DOES BEGIN TO INCREASE AFTER 0Z TUESDAY...THOUGH MODEL DIFFERENCES EXIST HERE AS WELL. LLJ AT THIS TIME EXPECTED TO BE FOCUSED ON SOUTHWEST IOWA. FOR POPS/WX WENT WITH A CONSENSUS APPROACH GIVEN THE MODEL DIFFERENCES AND CONVECTION UNCERTAINTY. HEAVY RAIN COULD BE A CONCERN GIVEN PRECIPITABLE WATER VALUES ARE AROUND 150 PERCENT OF NORMAL/AT 1.5-1.8 INCHES AND CORFIDI VECTORS EXHIBIT SLOW MOTIONS. ESPECIALLY IF THE HARDER HIT AREAS IN THE WESTERN HALF OF THE CWA SEE ADDITIONAL HEAVY RAINFALL. 925 HPA TEMPERATURES HAVE A BIT OF A SPREAD MONDAY WITH THE ECMWF COOLER THAN THE NAM/GFS. ALSO...WE HAVE BEEN A BIT WARM THE LAST FEW FCST IN REGARD TO HIGHS...SO WENT WITH CONSENSUS GUIDANCE AND STAYED AWAY FROM THE HIGHER INDIVIDUAL MODEL GUIDANCE. LONG TERM... WEDNESDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM. WARM TEMPERATURES AND HUMID CONDITIONS CONTINUE INTO THURSDAY. AFTER WHICH THE UPPER-LEVEL PATTERN CHANGES WITH A 500 HPA TROUGH DEVELOPING OVER THE GREAT LAKES REGION AND A NORTHWEST FLOW TAKING OVER. MODELS QUITE A BIT APART IN REGARD TO HOW THE PATTERN EVOLVES WITH THE GFS DIGGING NOTABLY STRONGER. BEST CHANCES FOR PRECIP WED AND OVERNIGHT WITH FRONTAL PASSAGE. SFC HIGH PRESSURE BEGINS TO BUILD IN AT THE END OF THE TIME PERIOD. AVIATION/12Z TAFS/... OTHER THAN PESKY MVFR VISIBILITY DROPS IN LIGHT FOG EARLY THIS MORNING AND AGAIN TONIGHT...GENERALLY VFR CONDITIONS OUTSIDE OF THUNDERSTORMS. EXPECT MVFR AT KMSN TONIGHT WITH THUNDERSTORMS AROUND BUT MUCH OF THE ACTIVITY COULD STAY WEST OF THE SOUTHEAST WI TAFS TONIGHT AND ESPECIALLY BEFORE MIDNIGHT. WITH ABOUT A 4 MB GRADIENT BETWEEN KGRB AND KUGN NOT EXPECTING MUCH INLAND PENETRATION OF THE LAKE BREEZE THIS AFTERNOON BUT WILL BE A CLOSE CALL AT KMKE IN THE 19-23Z PERIOD. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY EVENING FOR WIZ046-047-056-057-062-063-067>069. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN MONDAY THROUGH SATURDAY...ET
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
346 AM CDT SUN JUN 23 2013 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 346 AM CDT SUN JUN 23 2013 MAIN FORECAST CONCERNS THIS PACKAGE...SHRA/TSRA/HEAVY RAINS/SEVERE THREAT THROUGH THE PERIOD...TEMPERATURES. DATA ANALYSIS AT 06Z HAD LOW PRESSURE OVER EASTERN CO/WESTERN KS WITH A TROUGH NORTHEAST TO NEAR THE DAKOTAS/MN BORDER. A COUPLE OF BOUNDARIES/WEAKER TROUGHS EXTENDED EAST-WEST ACROSS NORTHERN IA AND WI/IL BORDER AND FROM NEAR KFSD TO NORTHWEST WI. THESE LAST TWO LIKELY ARTIFACTS OF BOTH ONGOING CONVECTION AND THAT FROM LAST NIGHT. LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE IMPINGING ON THE NORTHERN IA BOUNDARY PRODUCING ANOTHER ROUND OF HEAVY RAIN PRODUCING TSRA ACROSS EASTERN SD TO SOUTHERN WI. DANGEROUS FLASH FLOODING OCCURRING OVER FAR NORTHEAST IA AND FAR SOUTHWEST WI WHERE HEAVY RAINS HAVE FALLEN FOR THE SECOND STRAIGHT NIGHT. NO LARGE...GLARING ERRORS NOTED WITH 23.00Z MODEL INITIALIZATIONS... THOUGH PLENTY OF SMALLER/MESO-SCALE DIFFERENCES IN THE 850-500MB FIELDS. MUCH MORE THAN ONE WOULD LIKE TO SEE WHEN THE FCST AND SENSIBLE WEATHER OUTCOMES ARE KEYED TO THE SMALL SCALE FEATURES. DPROG/DT OF 500MB HGTS AT 23.00Z SHOWED THE MODEL RUNS OF 21.00Z AND 22.00Z VERIFIED WELL ACROSS NOAM/EASTERN PAC...AT LEAST WITH THE LARGER SCALE FEATURES. ALL EARLIER RUNS LOOKED TOO WEAK WITH THE SHORTWAVE FEATURES IN THE SOUTHWEST FLOW FROM MN/WI TO TX/CO. EVEN WITH SOME DIFFERENCES AT THE START...AT LEAST AT 500MB MODELS QUITE SIMILAR FOR TODAY/TONIGHT AS THE TROUGH EXITING THE NORTHERN ROCKIES LIFTS NORTHEAST INTO MAN/WESTERN ONT. SOME DIFFERENCES WITH THE TROUGH/LOW AT 12Z MON ONCE IT IS IN MAN/ONT BUT THIS WELL NORTH OF THE FCST AREA. MODELS SURPRISINGLY SIMILAR WITH A SMALL SOUTHWEST FLOW SHORTWAVE TO BE APPROACHING/CROSSING THE AREA MONDAY. CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED MOST WERE A BIT WEAK WITH A WAVE OF LOW PRESSURE OVER NORTHEAST NEB AND THE BOUNDARY ACROSS NORTHERN IA. MOST WERE STRUGGLING A BIT WITH SFC DEW POINTS IN THE MOISTURE PLUME OVER THE MID/UPPER MS VALLEY. PER WV IMAGERY AND REGIONAL RADAR REFLECTIVITY...ECMWF LOOKED A LITTLE BETTER WITH THE SHORTWAVE DETAILS ACROSS THE CENTRAL CONUS. MODELS AGAIN GENERALLY STRUGGLING WITH THE 00-06Z PRECIP ACROSS THE REGION. SOME BETTER IN AREAS THAN OTHERS BUT OVERALL NO ONE MODEL LOOKED BETTER THAN THE OTHERS. FAVORED A MODEL/ENSEMBLE CONSENSUS HEADED BY THE LOCAL REGIONAL WRF MODELS...WHICH WERE BETTER AT DEPICTING THE CONVECTION ACROSS THE AREA THRU THE EVENING HOURS. WITH THE MESO-SCALE DETAIL DIFFERENCES...SHORT-TERM FCST CONFIDENCE NEAR TO BELOW AVERAGE THIS CYCLE. PER THE MODEL CONSENSUS...FORCING FOR CONVECTION OVER THE AREA EARLY THIS MORNING LOOKS TO WANE AS THE SD SHORTWAVE LIFTS INTO MN. THIS INCREASES THE MID LEVEL FLOW AND TAKES MORE OF THE MOISTURE TRANSPORT WITH IT...PASSING NORTHWEST OF THE FCST AREA. ANY BREAK FROM THE CONVECTION THEN LOOKS TO BE SHORT LIVED. AS THE MAIN SHORTWAVE LIFTS ACROSS THE DAKOTAS TODAY IT PUSHES THE SFC-700MB TROUGH BACK TO THE EAST/SOUTH ALONG WITH THE LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE. AS THIS TROUGHING APPROACHES SHRA/TSRA EXPECTED TO DEVELOP ALONG IT THEN MOVE ACROSS THE FCST AREA DURING THE LATE AFTERNOON/EVENING HOURS. PW VALUES REMAIN IN THE 1.5 TO 2 INCH RANGE AND WARM CLOUD DEPTH OF 3.5 TO 4KM...ANY TSRA WILL ONCE AGAIN BE EFFICIENT RAIN PRODUCERS WITH THE THREAT OF MORE HEAVY RAINS ACROSS THE FCST AREA. GIVEN THE PAST 2 NIGHTS OF HEAVY RAINS AND NO ROOM TO PUT ANY MORE WATER...WILL ISSUE A FLASH FLOOD WATCH FOR ALL BUT CLARK/TAYLOR COUNTIES FROM 3 PM THIS AFTERNOON TO 7 AM MON MORNING. TRENDED RAIN CHANCES TOWARD 70 PERCENT WITH THE APPROACH/ PASSAGE OF THE SFC/LOW LEVEL TROUGH THIS AFTERNOON/EVENING. ML CAPES IN THE 2K-3K RANGE THIS AFTERNOON HOWEVER MOST OF THE SHEAR IS IN THE 0-3KM LAYER AT 15-30KTS. THIS WITH THE APPROACHING TROUGH/FRONT...FAVORABLE FORCING AND LOWER LEVEL WIND SHEAR FOR LINEAR CONVECTIVE SYSTEMS AND BOWING SEGMENTS FOR A DAMAGING WIND THREAT WITH MORE ORGANIZED TSRA. SEE SWODY1 FOR MORE DETAILS. APPEARS TO BE ANOTHER BREAK LATER TONIGHT/MON MORNING WITH THE MAIN FORCING/LIFT AND MOISTURE TRANSPORT PUSHED EAST/SOUTH OF THE AREA... BUT NOT BY FAR. IF MODEL CONSENSUS IS CORRECT WITH ANOTHER SOUTHWEST FLOW SHORTWAVE TO MOVE INTO THE REGION MON...LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE ARE AGAIN POINTED AT THE FCST AREA FOR MON AFTERNOON/EVENING. THIS WITH ML CAPES OF 2K TO 4K J/KG AND PW VALUES OF 1.5 TO 2 INCHES IN THE INFLOW AIRMASS. RAISED SHRA/TSRA CHANCES FOR MON AFTERNOON BUT MORE OF THIS MAY BE INTO MONDAY EVENING/NIGHT. THE WAY THINGS HAVE BEEN GOING...ITS LIKELY ANOTHER FLASH FLOOD WATCH WILL BE NEEDED FOR MON NIGHT. USED A MODEL/ENSEMBLE CONSENSUS FOR HIGHS/LOWS TODAY THRU MON. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 346 AM CDT SUN JUN 23 2013 MODEL CONSENSUS TREND FOR MON NIGHT THRU TUE NIGHT IS STRONGER WITH ANOTHER SHORTWAVE TROUGH TO COME OUT OF THE ROCKIES MON NIGHT AND END UP OVER THE UPPER MIDWEST BY WED MORNING. HOWEVER RUN-TO-RUN CONSISTENCY ON THIS FEATURE NOT THAT GOOD. FCST CONFIDENCE IN THIS PERIOD AVERAGE. MON NIGHT THRU TUE NIGHT LOOKS LIKE A CONTINUATION OF THE UNSETTLED/ WET STRETCH OF DAYS. THE VERY MOIST AND UNSTABLE AIRMASS WILL REMAIN IN PLACE OVER THE REGION THRU TUE NIGHT. THIS AS MORE SHORTWAVE ENERGY RIPPLES THRU THE FLOW AND ACROSS THE REGION AND ONE OR MORE FRONTAL BOUNDARY NEAR OR MOVING ACROSS THE FCST AREA. COMPLEX OF SHRA/TSRA INITIATED MON AFTERNOON EXPECTED TO BE MOVING ACROSS THE REGION MON NIGHT. AFTER THIS ONE CLEARS THE AREA/ DIMINISHES TUE MORNING...ATMOSPHERE LOOKS TO QUICKLY RELOAD. WITH THE APPROACH OF ANOTHER SHORTWAVE AND AN INCREASING LOW LEVEL JET AND MOISTURE TRANSPORT TOWARD THE AREA...YET ANOTHER CONVECTIVE COMPLEX WITH THE THREAT OF MORE HEAVY RAINS LOOKS TO DEVELOP MOVE ACROSS SOME PORTION OF IA/MN/WI. DIFFERENCES IN THE DETAILS BY TUE/TUE NIGHT SO PLENTY OF UNCERTAINTY ON WHERE THE GREATEST HEAVY RAIN THREAT WOULD BE. DUE TO THE CONVECTION UNKNOWNS...FOR NOW USED THE MODEL/ENSEMBLE CONSENSUS OF LOWS/HIGHS MON NIGHT THRU TUE NIGHT. MEDIUM RANGE MODEL RUNS OF 23.00Z CONTINUE TO SHOW A PATTERN TRANSITION IN THE WED-SAT PERIOD. INCREASING SIGNAL FOR RIDGING TO BUILD OVER THE WESTERN CONUS WITH DOWNSTREAM NORTHWEST FLOW DEVELOPING OVER THE UPPER MIDWEST. GIVEN DECENT BETWEEN MODEL AND RUN-TO-RUN CONSISTENCY...FCST CONFIDENCE IN THE DAY 4-7 PERIOD AVERAGE TO GOOD THIS CYCLE. WED-SAT TRENDING TO BE A DRIER/COOLER PERIOD AS THE FLOW TRANSITIONS TO THE NORTHWEST. APPEARS TUE NIGHT/WED MORNING MAY BE THE LAST OF THE CONVECTIVE COMPLEX/HEAVY RAIN THREATS. FLOW BECOMES BRIEFLY WESTERLY/ZONAL WED WITH THE MID LEVEL TROUGH AND SFC LOW MOVING EAST OF THE REGION. THIS CHANGE PUSHES THE VERY MOIST AIRMASS OUT OF THE AREA. SHRA/TSRA STILL POSSIBLE WED INTO THU NIGHT WITH PASSAGE OF THE SFC LOW WED THEN WEAK NORTHWEST FLOW SHORTWAVES WED NIGHT INTO SAT. ANY OF THESE SHRA/TSRA THESE WOULD BE MUCH MORE SCATTERED IN COVERAGE /ESPECIALLY BY THU/...HAVE LESS MOISTURE/INSTABILITY TO WORK WITH AND BE MORE DIURNALLY DRIVEN. SMALLER MODEL CONSENSUS SHRA/TSRA CHANCES FOR MUCH OF THE WED-SAT PERIOD LOOK REASONABLE AT THIS TIME. MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR THIS PERIOD LOOK GOOD AS WELL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1237 AM CDT SUN JUN 23 2013 BOUNDARY ACROSS NORTHEAST IOWA INTO SOUTHWEST WISCONSIN HAS SHOWN NO MOVEMENT THROUGH THE EVENING HOURS WITH STORMS CONTINUING ALONG AND NORTH OF IT. REGIONAL AND LOCAL RADAR DOES SHOW A BREAK IN THE ACTIVITY BACK IN THE INTERSTATE 35 CORRIDOR. THE NEXT ROUND OF CONVECTION OVER SOUTHWEST MINNESOTA INTO SOUTH DAKOTA HAS A MORE NORTHEAST MOVEMENT. THE LAST TWO RUNS OF THE LOCAL ARX-LAPS HAS LATCHED ONTO THESE DIFFERENT AREAS OF CONVECTION WITH THE 23.03Z RUN TAKING THE ACTIVITY OVER THE AREA OFF TO THE EAST AND OUT OF THE REGION DURING THE OVERNIGHT WHILE TAKING THE NEXT ROUND PAST THE AREA TO THE NORTH. THE 23.03Z HRRR SHOWS THE SAME TRENDS SO PLAN TO CONTINUE THE TSRA THROUGH 08Z AT KRST AND 10Z AT KLSE. AFTER THAT WILL JUST DROP BACK TO VCSH FOR A SHORT WHILE BEFORE GOING TOTALLY DRY FOR THE REMAINDER OF THE MORNING. MVFR CONDITIONS WILL BE POSSIBLE WITH ANY OF THE TSRA ACTIVITY UNTIL IT ENDS. BY MID TO LATE AFTERNOON...THE 23.00Z NAM INDICATES THE SYNOPTIC BOUNDARY SHOULD PUSH INTO THE AREA WITH A SHORT WAVE TROUGH AND AS THE UPPER LEVEL FLOW TRIES TO TURN A LITTLE MORE TO THE WEST. SHOULD SEE MORE CONVECTION DEVELOP ALONG THIS BOUNDARY AND HAVE PUT IN A VCTS TO SHOW THIS WITH THE EXPECTATION THAT LATER FORECASTS WILL DETAIL THE TIMING BETTER. && .HYDROLOGY... ISSUED AT 346 AM CDT SUN JUN 23 2013 FLOODING AND FLASH FLOODING ONGOING ACROSS PORTIONS OF THE FCST AREA THIS MORNING...ALONG THE MN/IA BORDER INTO FAR SOUTHWEST WI. THIS BEING COVERED BY FLASH FLOOD AND AREAL FLOOD WARNINGS. DUE TO THE RECENT RAINS OF THE PAST FEW DAYS...SATURATED SOILS AND THE THREAT FOR ANOTHER ROUND OF 1/2 TO 1 INCH OF RAIN...LOCALLY 2 INCHES OR MORE IN REPEATING TSRA LATER THIS AFTERNOON AND TONIGHT WITH THE APPROACH OF THE SFC THRU MID LEVEL TROUGH...WILL ISSUE A FLASH FLOOD WATCH FROM 3 PM THIS AFTERNOON TO 7 AM MONDAY. TRIBUTARY RIVERS LIKE THE KICAKPOO...BLACK...UPPER IOWA AND TURKEY RIVERS CONTINUE TO RISE AND REACH FLOOD STAGE AS WELL. ADDITIONAL HEAVY RAINS AND HIGH RUNOFF PERCENTAGES WILL ONLY CREATE MORE PROBLEMS WITH THESE LARGER RIVERS...ESPECIALLY AS THIS PERIOD OF STORMY WEATHER AND THREAT OF MORE ROUNDS OF HEAVY RAINS CONTINUES. IN ADDITION TO THE SHORT TERM WATER CONCERNS...THERE IS A RIVER FLOOD WATCH FOR THE MISSISSIPPI AT WABASHA...WINONA...AND LA CROSSE. WATER FROM THE TRIBUTARY RIVERS...AND RIVERS NORTH OF THE FCST AREA WILL EVENTUALLY MAKE ITS WAY INTO THE MS RIVER...WITH THE MS RIVER AT THESE LOCATIONS EXPECTED TO RISE ABOVE FLOOD STAGE AROUND OR AFTER THE 1ST OF JULY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY MORNING FOR WIZ032>034-041>044-053>055-061. MN...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY MORNING FOR MNZ079-086>088-094>096. IA...FLASH FLOOD WATCH FROM 3 PM CDT THIS AFTERNOON THROUGH MONDAY MORNING FOR IAZ008>011-018-019-029-030. && $$ SHORT TERM...RRS LONG TERM....RRS AVIATION.....04 HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1238 AM CDT SUN JUN 23 2013 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 253 PM CDT SAT JUN 22 2013 AT 3 PM...A WARM FRONT WAS LOCATED NEAR THE INTERSTATE 94 CORRIDOR AND AN OUTFLOW BOUNDARY OVER NORTHERN IOWA. AS THE TEMPERATURES RISE ABOVE THE CONVECTIVE TEMPERATURES /LOWER 80S/ LATE THIS AFTERNOON...EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR. IN ADDITION... EXPECT THE SYSTEM MOVING OUT OF NORTHWEST IOWA TO GRADUALLY UPSCALE AS IT MOVES INTO BETTER CAPES AND MOISTURE TRANSPORT. WITH 0-3 KM SHEAR GREATER THAN 40 KNOTS...THINKING THAT THE STORMS BECOME MORE COLD POOL DOMINATED THAT THERE WILL ONCE AGAIN BE THE POTENTIAL FOR SOME BOW ECHOS TO DEVELOP LATE THIS AFTERNOON AND EVENING. IN ADDITION...WITH 1000 TO 1200 J/KG DCAPES THERE WILL BE THE POTENTIAL FOR DAMAGING WET MICROBURSTS. WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.8 AND 2.0 INCHES AND WARM CLOUDS DEPTHS BETWEEN 4 AND 4.5 KM...EXPECT THE THUNDERSTORMS TO BE VERY EFFECTIVE RAIN PRODUCERS. HOWEVER IT LOOKS LIKE THEY WILL BE PROGRESSIVELY MOVING WHICH WILL LIMIT THE THREAT FOR WIDESPREAD FLASH FLOODING. HOWEVER WITH THIS SAID...WILL STILL HAVE TO WATCH URBANIZED AREAS WHERE JUST AN INCH OF RAIN AN HOUR CAN RESULT IN SOME LOCALIZED FLASH FLOODING. FOR OVERNIGHT...THE 23.12Z DETERMINISTIC MODELS CONTINUE TO SHOW THAT MUCH OF THE PRECIPITATION FOR THIS TIME PERIOD WILL BE MAINLY NORTH OF THE INTERSTATE 90 CORRIDOR. THEY HAVE SHOWED THIS FOR THE PAST 6 MODEL CYCLES. THIS IS IN RESPONSE TO THE TROUGH CURRENTLY OVER NEBRASKA MOVING NORTHEAST AWAY FROM THE FORECAST AREA. AS THIS OCCURS...THE NOSE OF THE 850 MB MOISTURE TRANSPORT WILL PUSH NORTH INTO NORTHERN WISCONSIN. IN THE WAKE OF THIS TROUGH...THE PRECIPITABLE WATER VALUES DROP TO 1.2 TO 1.4 INCHES...AND THE WARM CLOUD LAYER DEPTHS FALL INTO THE 3.5 TO 4 KM RANGE. THIS IS IDEA THAT THE PRECIPITATION COULD BEGIN WANING OVERNIGHT IS SUPPORTED BY THE LAST 2 RUNS OF THE HRRR WHICH SHOWS A BAND OF SHOWERS AND THUNDERSTORMS PROGRESSIVELY MOVING NORTHEAST THROUGH CLARK AND TAYLOR COUNTIES IN NORTH CENTRAL WISCONSIN BETWEEN 23.07Z AND 23.09Z. FOR SUNDAY AFTERNOON...EXPECT THE UPPER LEVEL TROUGH WHICH HAS BEEN POSITIONED TO OUR WEST OVER THE LAST SEVERAL DAYS TO MOVE INTO THE WESTERN PORTIONS OF THE FORECAST AREA. WHILE THE 850 MB MOISTURE TRANSPORT IS NOT THAT IMPRESSIVE. PRECIPITABLE WATER VALUES DO CLIMB TO AROUND 1.8 INCHES...WARM CLOUD LAYER DEPTHS CLIMB ABOVE 4 KM...AND CORFIDI VECTORS SUGGEST TRAINING ALONG AND AHEAD OF THE COLD FRONT. AS A RESULT...WILL HAVE TO WATCH FOR THE POTENTIAL FOR SOME FLOODING. CERTAINTY ON THE SPEED AND LOCATION OF THIS FRONT WAS NOT HIGH ENOUGH TO GO WITH A FLASH FLOOD WATCH AT THIS TIME. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 253 PM CDT SAT JUN 22 2013 ON SUNDAY NIGHT AND MONDAY...THE MODELS CONTINUE TO SHOW THAT A SHORT WAVE TROUGH WILL MOVE ACROSS WESTERN AND NORTHERN MINNESOTA. AS THIS OCCURS...EXPECT A COLD FRONT TO MOVE THROUGH THE REGION. THIS FRONT WILL BE THE FOCUS FOR ADDITIONAL SHOWER AND THUNDERSTORM ACTIVITY. IT MAY MOVE FAR ENOUGH EAST TO ALLOW SOME DRYING ON MONDAY AFTERNOON. FROM MONDAY NIGHT THROUGH WEDNESDAY...THE MODELS CONTINUE TO SHOW THAT A STATIONARY FRONT WILL LINGER ACROSS THE AREA. WHILE THE MODELS HAVE CONSISTENTLY SHOWED THIS...THEY CONTINUE TO STRUGGLE ON THE LOCATION AND TIMING OF THUNDERSTORM COMPLEXES WHICH MOVE THROUGH THE REGION...SO JUST WENT WITH THE ALL BLEND TEMPERATURES AND PRECIPITATION CHANCES. FOR THE REMAINDER OF THIS TIME PERIOD...IT CONTINUES TO LOOK LIKE THE UPPER LEVEL RIDGE WILL RETROGRADE WEST INTO THE WESTERN UNITED STATES. THIS WOULD PLACE THE AREA UNDER NORTHWEST FLOW ALOFT. AS A RESULT...EXPECT NEAR TO SLIGHTLY BELOW-NORMAL TEMPERATURES. PRECIPITATION CHANCES ARE NOT CLEAR AS THERE WILL THE POTENTIAL FOR SHORT WAVE TROUGHS TO MOVE SOUTHEAST THROUGH THE AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1237 AM CDT SUN JUN 23 2013 BOUNDARY ACROSS NORTHEAST IOWA INTO SOUTHWEST WISCONSIN HAS SHOWN NO MOVEMENT THROUGH THE EVENING HOURS WITH STORMS CONTINUING ALONG AND NORTH OF IT. REGIONAL AND LOCAL RADAR DOES SHOW A BREAK IN THE ACTIVITY BACK IN THE INTERSTATE 35 CORRIDOR. THE NEXT ROUND OF CONVECTION OVER SOUTHWEST MINNESOTA INTO SOUTH DAKOTA HAS A MORE NORTHEAST MOVEMENT. THE LAST TWO RUNS OF THE LOCAL ARXLAPS HAS LATCHED ONTO THESE DIFFERENT AREAS OF CONVECTION WITH THE 23.03Z RUN TAKING THE ACTIVITY OVER THE AREA OFF TO THE EAST AND OUT OF THE REGION DURING THE OVERNIGHT WHILE TAKING THE NEXT ROUND PAST THE AREA TO THE NORTH. THE 23.03Z HRRR SHOWS THE SAME TRENDS SO PLAN TO CONTINUE THE TSRA THROUGH 08Z AT KRST AND 10Z AT KLSE. AFTER THAT WILL JUST DROP BACK TO VCSH FOR A SHORT WHILE BEFORE GOING TOTALLY DRY FOR THE REMAINDER OF THE MORNING. MVFR CONDITIONS WILL BE POSSIBLE WITH ANY OF THE TSRA ACTIVITY UNTIL IT ENDS. BY MID TO LATE AFTERNOON...THE 23.00Z NAM INDICATES THE SYNOPTIC BOUNDARY SHOULD PUSH INTO THE AREA WITH A SHORT WAVE TROUGH AND AS THE UPPER LEVEL FLOW TRIES TO TURN A LITTLE MORE TO THE WEST. SHOULD SEE MORE CONVECTION DEVELOP ALONG THIS BOUNDARY AND HAVE PUT IN A VCTS TO SHOW THIS WITH THE EXPECTATION THAT LATER FORECASTS WILL DETAIL THE TIMING BETTER. && .HYDROLOGY... ISSUED AT 253 PM CDT SAT JUN 22 2013 HYDRO CONCERNS LINGER ACROSS TURKEY...UPPER IOWA...SOUTHERN HALF OF THE KICKAPOO...BLACK...AND TURTLE CREEK. IN ADDITION...THE SMALL STREAMS ACROSS ALLAMAKEE AND CLAYTON COUNTIES IN NORTHEAST IOWA... AND CRAWFORD AND GRANT COUNTIES IN SOUTHWEST WISCONSIN. FORTUNATELY IT LOOKS LIKE THE HEAVIEST RAIN POTENTIAL FOR TONIGHT WILL BE MAINLY NORTH OF MOST OF THESE BASINS. HOWEVER THERE IS CONCERN ON SUNDAY THAT THERE COULD BE ANOTHER ROUND OF HEAVY RAIN THAT COULD AFFECT THE AREA ON SUNDAY AFTERNOON AND NIGHT. HOWEVER DUE TO THE UNCERTAINTY ON THE SPEED OF THIS SYSTEM...RAINFALL AMOUNTS ARE NOT CLEAR. IN ADDITION TO THE SHORT TERM WATER CONCERNS...THERE IS A RIVER FLOOD WATCH FOR THE MISSISSIPPI AT WABASHA...WINONA...AND LA CROSSE. THESE RIVERS ARE EXPECTED TO GO ABOVE FLOOD STAGE UNTIL AFTER JULY 1ST. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...04 HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1053 PM MDT SAT JUN 22 2013 .UPDATE... ISSUED AT 938 PM MDT SAT JUN 22 2013 SHOWERS AND TSTMS ARE REALLY BEGINNING TO WIND DOWN AS THE STRONG SHORTWAVE PASSES ACROSS THE CWA AND THE SUBSIDENCE FOLLOWS. KEPT SCATTERED SHOWERS IN THE NEBRASKA PANHANDLE THROUGH MIDNIGHT THEN REMOVED ANY MENTION OF PRECIP. SHOULD BE A QUIET NIGHT AS A WEAK FRONTAL PASSAGE SWITCHES WINDS TO THE NORTH. THE NAM SUGGESTS LOW CLOUDS WILL BE POSSIBLE OVER THE PLAINS LATER TONIGHT WHEREAS THE GFS IS DRIER IN THE LLVLS. WILL KEEP LOW CLOUDS OUT OF THE GRIDS FOR NOW WITH THE HRRR ONLY SHOWING IFR CIGS ALONG THE SOUTHERN LARAMIE RANGE EASTWARD INTO LARAMIE COUNTY. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 417 PM MDT SAT JUN 22 2013 THE CLUSTER OF THUNDERSTORMS MOVING THROUGH AREAS EAST OF THE LARAMIE RANGE WILL CONTINUE TO SHIFT EAST DURING THE COURSE OF THE EVENING. 0-1KM STORM RELATIVE HELICITY VALUES ARE RANGING FROM 50-100M^2/S^2 IN GOSHEN AND ALBANY COUNTIES. FURTHER EAST OF THIS LCLS ARE A BIT LOWER WITH VALUES RANGING FROM 500M- 1000M. THEREFORE...CONTINUED TORNADO THREAT LOOKS TO BE FAIRLY MARGINAL THIS EVENING...BUT STILL CANNOT RULE SOME BRIEF TOUCHDOWNS AS THE LINE CONTINUES TO PUSH EAST. MEANWHILE...LARGE HAIL AND DAMAGING WIND THREAT STILL LOOKS FAVORABLE AT THIS TIME. ALL OF THIS ACTIVITY CONTINUES TO DEVELOP AHEAD OF THE MAIN SHORTWAVE PIVOTING THROUGH CENTRAL WYOMING. THIS SHORTWAVE WILL CONTINUE TO SHIFT EAST THIS EVENING AND BRING DRIER AIR INTO THIS EVENING. WE WILL BE CLEARING THE TORNADO WATCH IN CONVERSE AND ALBANY COUNTIES SHORTLY. TONIGHT AND SUNDAY: CLEARING SKIES ARE EXPECTED LATE THIS EVENING AND OVERNIGHT AS THE SUBSIDENCE BUILDS IN WITH THE PASSING SHORTWAVE. IT MAY BE QUITE COOL IN A FEW LOCATIONS WITH 40S IN WYOMING AND 50S IN THE NEBRASKA PANHANDLE. LEE SIDE TROF DOES TRY TO SET UP CAMP...BUT NOT REAL CONFIDENT THAT SHOWERS AND STORMS WILL DEVELOP. FOR NOW...WE WILL CONSISTENCY SAKE WE WILL KEEP THE CHANCE OF SHOWERS AND THUNDERSTORMS IN THE PICTURE. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 417 PM MDT SAT JUN 22 2013 NOT MANY CHANGES MADE TO THE LONG TERM DUE TO WIDESPREAD SEVERE WEATHER THIS AFTERNOON. WE WILL NEED TO WATCH FOR A POTENTIAL SHORTWAVE MOVING THROUGH THE NORTHERN PARTS OF THE FORECAST AREA MONDAY NIGHT AND TUESDAY WHICH MAY BRING A CHANCE OF SHOWERS OF THUNDERSTORMS. OTHERWISE...THE UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE REGION LATER IN THE WEEK AND BRING WARMER TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING) ISSUED AT 1053 PM MDT SAT JUN 22 2013 THUNDERSTORM ACTIVITY HAS SLID EAST OF AREA TERMINALS LATE THIS EVENING...GIVING WAY TO DRIER CONDITIONS DURING THE MORNING HOURS. A WEAK FRONT WILL SURGE SOUTH POTENTIALLY PRODUCING TO MVFR CIGS FOR A TIME AT KCYS...KCDR AND KAIA BETWEEN 08Z-13Z. OTHERWISE...ANTICIPATE VFR CONDITIONS TO PREVAIL THROUGH THE MORNING. ANOTHER ROUND OF -TSRA ARE EXPECTED FOR KCYS...KBFF AND KSNY ON SUNDAY AFTERNOON...SO HAVE ADDED VCTS MENTION TO THOSE AIRFIELDS AFTER 18Z. && .FIRE WEATHER... ISSUED AT 417 PM MDT SAT JUN 22 2013 LOW RELATIVE HUMIDITIES WILL BE IN STORE FOR AREAS MAINLY WEST OF THE LARAMIE RANGE SUNDAY AFTERNOON. OTHERWISE...THE LEE SIDE TROF IS EXPECTED TO DEVELOP OVER THE AREA ON MONDAY WITH GUSTY AND DRY SOUTHWEST FLOW POSSIBLE WEST OF THE LARAMIE RANGE ON MONDAY WHICH WILL FAVOR INCREASED FIRE RISK. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...FINCH SHORT TERM...REC LONG TERM...SLA AVIATION...CH FIRE WEATHER...REC
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1027 PM PDT MON JUN 24 2013 .DISCUSSION...AS OF 9:15 PM PDT MONDAY...KMUX RADAR CONTINUES TO SHOW HIT AND MISS SHOWERS ACROSS THE BAY AREA WITH RAIN TOTALS GENERALLY ON THE LIGHT SIDE SO FAR WITH MOST LOCALES LESS THAN A TENTH OF AN INCH EXCEPT 0.25-0.30 FOR THE SONOMA COAST. AS ONE CAN FEEL THERE IS PLENTY OF AVAILABLE MOISTURE WITH DEWPOINTS HOVERING AROUND 60 DEGREES WITH LAYERED CLOUD DECKS AND EVEN SOME DENSE FOG SHOWING UP AROUND HALF MOON BAY. AS HAS BEEN THE CASE THE LAST 24 HOURS THERE CONTINUES TO BE NO FOCUSED FORCING OR DYNAMICS TO REALLY GENERATE ANY APPRECIABLE PRECIP. ALL OF OUR SHORT TERM MODELS...THE 00Z NAM AS WELL AS THE LATEST IN HOUSE WRF AND NCEP RAP MODEL SHOW THE LAST GOOD CHANCE OF GENERATING NOTEWORTHY RAINFALL WILL OCCUR OVERNIGHT THROUGH THE MORNING HOURS OF TUESDAY. AS HAS BEEN THE CASE ALL ALONG THE NORTH BAY AND IN PARTICULAR SONOMA COUNTY WILL SEE THE BEST SHOT OF RAIN TOTALS IN EXCESS OF 0.50 TO 1 INCH. FROM AN IMPACT STANDPOINT WE CAN EXPECT WET ROADS FOR THE MORNING COMMUTE FOR THE GREATER BAY AREA AS WELL AS THE NORTH BAY WITH THE 101 CORRIDOR AND POINTS NORTHWARD MOST DIRECTLY IMPACTED. ANY RAIN SOUTH OF THE SANTA CRUZ MOUNTAINS LOOKS TO BE SPOTTY AND LIGHT. OF COURSE ANY RAINFALL ON JUNE 25TH IS RARE SO WE SHOULD BE ABLE TO BREAK SOME DAILY RAINFALL RECORDS BEFORE MIDNIGHT TONIGHT AS WELL AS FOR TUESDAY. THE MOST CONSISTENT SITE FOR RECORDS SUCH AS THIS IS DOWNTOWN SF AND THAT DAILY RECORD IS 0.15 BACK IN 2001. IN GENERAL SHOWERS BECOME ISOLATED BY MIDDAY TUESDAY ALTHOUGH CHANCES WILL LINGER IN THE NORTH BAY THROUGH TUESDAY EVENING. THE ABSENCE OF COLD ADVECTION WILL LIKELY LEAD TO MORE LOW CLOUD AND FOG FORMATION TUESDAY NIGHT INTO WEDS MORNING. THERE IS NOTHING TO WASH THE HIGH DEWPOINT AIR OUT WITH SOUTHERLY WINDS STAYING IN PLACE BEHIND THE WARM FRONT. THE LACK OF NW WINDS OVER THE OCEAN WILL KEEP UPWELLING NEARLY NON-EXISTENT AND SST WILL HOVER IN THE UPPER 50S AS WELL. ANYWAY WEDS WILL BE A TRANSITION DAY WITH DRY WEATHER BUT A WARMING AIRMASS. THE HIGH DEWPOINTS WILL KEEP THINGS ALMOST UNCOMFORTABLE FOR THOSE FOLKS NOT ACCUSTOMED TO THE HEAT. LUCKILY BY THURSDAY AS THE RIDGE REALLY STARTS TO BUILD IN WE SHOULD GET A RETURN OF NW WIND FLOW. A DOMINANT WESTERN US RIDGE WILL BECOME THE MAIN WEATHER STORY FOR THE ENTIRE WESTERN HALF OF THE COUNTRY WITH BIG TIME HEAT FOR MOST OF THE WESTERN HALF OF THE US. THE INLAND LOCATIONS WILL RAPIDLY WARM WHILE THE COAST WILL KEEP A MARINE LAYER IN PLACE AT LEAST HEADING INTO THE WEEKEND. THERE ARE SOME INDICATIONS THAT THE RIDGE COULD BUILD TOWARDS CALIFORNIA AND ESSENTIALLY PUSH THE SURFACE THERMAL TROUGH NEAR THE COAST WITH HOT WEATHER PUSHING CLOSE TO THE BEACHES BY EARLY NEXT WEEK. LOOKS HOT AND DRY HEADING INTO THE FOURTH OF JULY HOLIDAY FOR MOST OF THE STATE. && .AVIATION...AS OF 10:30 PM PDT MONDAY...A VERY MOIST AIRMASS WILL REMAIN OVER THE AREA TONIGHT AND TUESDAY. LIGHT WINDS AND INCREASING LOW LEVEL STABILITY TONIGHT FAVORS IFR CEILINGS AND VISIBILITIES. VICINITY OF KSFO...VFR/MVFR CONDITIONS WILL LIKELY TREND TO IFR OVERNIGHT. SURFACE WINDS WILL KICK UP A LITTLE BY MID-LATE TUESDAY MORNING WHICH SHOULD HELP LIFT CEILINGS AND VISIBILITIES BACK TO MVFR AFTER 18Z. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...EXPECT IFR TONIGHT WITH OCCASIONAL LIGHT DRIZZLE. CEILINGS GRADUALLY LIFT BACK TO MVFR BY 17Z TUESDAY. && .MTR WATCHES/WARNINGS/ADVISORIES... .TNGT...NONE. $$ PUBLIC FORECAST: RWW AVIATION/MARINE: CANEPA VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
915 PM PDT MON JUN 24 2013 .DISCUSSION...AS OF 9:15 PM PDT MONDAY...KMUX RADAR CONTINUES TO SHOW HIT AND MISS SHOWERS ACROSS THE BAY AREA WITH RAIN TOTALS GENERALLY ON THE LIGHT SIDE SO FAR WITH MOST LOCALES LESS THAN A TENTH OF AN INCH EXCEPT 0.25-0.30 FOR THE SONOMA COAST. AS ONE CAN FEEL THERE IS PLENTY OF AVAILABLE MOISTURE WITH DEWPOINTS HOVERING AROUND 60 DEGREES WITH LAYERED CLOUD DECKS AND EVEN SOME DENSE FOG SHOWING UP AROUND HALF MOON BAY. AS HAS BEEN THE CASE THE LAST 24 HOURS THERE CONTINUES TO BE NO FOCUSED FORCING OR DYNAMICS TO REALLY GENERATE ANY APPRECIABLE PRECIP. ALL OF OUR SHORT TERM MODELS...THE 00Z NAM AS WELL AS THE LATEST IN HOUSE WRF AND NCEP RAP MODEL SHOW THE LAST GOOD CHANCE OF GENERATING NOTEWORTHY RAINFALL WILL OCCUR OVERNIGHT THROUGH THE MORNING HOURS OF TUESDAY. AS HAS BEEN THE CASE ALL ALONG THE NORTH BAY AND IN PARTICULAR SONOMA COUNTY WILL SEE THE BEST SHOT OF RAIN TOTALS IN EXCESS OF 0.50 TO 1 INCH. FROM AN IMPACT STANDPOINT WE CAN EXPECT WET ROADS FOR THE MORNING COMMUTE FOR THE GREATER BAY AREA AS WELL AS THE NORTH BAY WITH THE 101 CORRIDOR AND POINTS NORTHWARD MOST DIRECTLY IMPACTED. ANY RAIN SOUTH OF THE SANTA CRUZ MOUNTAINS LOOKS TO BE SPOTTY AND LIGHT. OF COURSE ANY RAINFALL ON JUNE 25TH IS RARE SO WE SHOULD BE ABLE TO BREAK SOME DAILY RAINFALL RECORDS BEFORE MIDNIGHT TONIGHT AS WELL AS FOR TUESDAY. THE MOST CONSISTENT SITE FOR RECORDS SUCH AS THIS IS DOWNTOWN SF AND THAT DAILY RECORD IS 0.15 BACK IN 2001. IN GENERAL SHOWERS BECOME ISOLATED BY MIDDAY TUESDAY ALTHOUGH CHANCES WILL LINGER IN THE NORTH BAY THROUGH TUESDAY EVENING. THE ABSENCE OF COLD ADVECTION WILL LIKELY LEAD TO MORE LOW CLOUD AND FOG FORMATION TUESDAY NIGHT INTO WEDS MORNING. THERE IS NOTHING TO WASH THE HIGH DEWPOINT AIR OUT WITH SOUTHERLY WINDS STAYING IN PLACE BEHIND THE WARM FRONT. THE LACK OF NW WINDS OVER THE OCEAN WILL KEEP UPWELLING NEARLY NON-EXISTENT AND SST WILL HOVER IN THE UPPER 50S AS WELL. ANYWAY WEDS WILL BE A TRANSITION DAY WITH DRY WEATHER BUT A WARMING AIRMASS. THE HIGH DEWPOINTS WILL KEEP THINGS ALMOST UNCOMFORTABLE FOR THOSE FOLKS NOT ACCUSTOMED TO THE HEAT. LUCKILY BY THURSDAY AS THE RIDGE REALLY STARTS TO BUILD IN WE SHOULD GET A RETURN OF NW WIND FLOW. A DOMINANT WESTERN US RIDGE WILL BECOME THE MAIN WEATHER STORY FOR THE ENTIRE WESTERN HALF OF THE COUNTRY WITH BIG TIME HEAT FOR MOST OF THE WESTERN HALF OF THE US. THE INLAND LOCATIONS WILL RAPIDLY WARM WHILE THE COAST WILL KEEP A MARINE LAYER IN PLACE AT LEAST HEADING INTO THE WEEKEND. THERE ARE SOME INDICATIONS THAT THE RIDGE COULD BUILD TOWARDS CALIFORNIA AND ESSENTIALLY PUSH THE SURFACE THERMAL TROUGH NEAR THE COAST WITH HOT WEATHER PUSHING CLOSE TO THE BEACHES BY EARLY NEXT WEEK. LOOKS HOT AND DRY HEADING INTO THE FOURTH OF JULY HOLIDAY FOR MOST OF THE STATE. && .AVIATION...AS OF 5:20 PM PDT MONDAY...ABUNDANT MOISTURE IS AROUND THE ENTIRE AREA PER WEATHER OBS...SATELLITE AND RADAR DATA. WINDS ARE EXPECTED TO REMAIN MOSTLY LIGHT THROUGH THE EVENING AND OVERNIGHT AT 10 KNOTS OR LESS. THE MAIN CONCERN TONIGHT IS THE POTENTIAL FOR IFR AND THE RATE AT WHICH IT DEVELOPS. THE JET STREAM IS BEGINNING TO DEPART AND LIFT NORTH AWAY FROM THE AREA HOWEVER A LOW LEVEL WARM AIR ADVECTION DEVELOPS AND PROVIDES THE LIFT NEEDED FOR ADDITIONAL RAIN OR DRIZZLE TONIGHT. A SURFACE TROUGH ARRIVES JUST AFTER DAYBREAK TUESDAY. MODELS ALSO FORECAST STEADILY INCREASING 500 MB HEIGHTS TONIGHT AND TUESDAY SUGGESTING GREATER AIRMASS STABILITY THAN LAST NIGHT WHICH SUGGESTS GREATER IFR POTENTIAL. VICINITY OF KSFO...CIGS HAVE SLIPPED A BIT LOWER IN THE LAST HOUR PER METAR OBS...BUT THERE REMAINS MODERATE CONFIDENCE THAT MVFR/VFR WILL HOLD FOR THE EVENING. ONSET OF NIGHT HOURS...VERY MOIST AIRMASS...LIGHT SURFACE WINDS...LIGHT PRECIPITATION AND STEADILY INCREASING AIRMASS STABILITY OVERNIGHT AND TUESDAY LEADS TO SOME CONCERN FOR IFR POTENTIAL LATE AT NIGHT AND TUE MORNING. KSFO BRIDGE APPROACH...SIMILAR TO KSFO. MONTEREY BAY AREA TERMINALS...MODERATE CONFIDENCE MVFR/VFR CONDITIONS ARE EXPECTED THIS EVENING. STEADILY LOWERING CIGS ARE EXPECTED AFTER 06Z WITH OCCASIONAL LIGHT RAIN OR DRIZZLE. && .MTR WATCHES/WARNINGS/ADVISORIES... .TNGT...NONE. $$ PUBLIC FORECAST: RWW AVIATION/MARINE: CANEPA VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK, TWITTER, AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.SANFRANCISCOBAYAREA.GOV WWW.TWITTER.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
130 AM EDT TUE JUN 25 2013 .UPDATE... /ISSUED AT 1107 PM EDT MON JUN 24 2013/ HAVE MADE SEVERAL TWEAKS TO GRIDS THROUGH THE EVENING...MAINLY TO UPDATE TRENDS IN POPS. REDUCED POPS SIGNIFICANTLY ESPECIALLY NORTH AND TRENDED THEM DOWN SOUTH AS WELL...WITH AN OVERALL REDUCTION THROUGH THE OVERNIGHT HOURS...TRENDING BACK UP DURING THE DAY ON TUESDAY. ADDED PATCHY FOG TO WEATHER GRID WORDING. UPDATED PRODUCTS ALREADY SENT. TDP && .PREV DISCUSSION... /ISSUED 339 PM EDT MON JUN 24 2013/ SHORT TERM /TONIGHT THROUGH TUESDAY/... 500MB SURFACE ANALYSIS SHOWS A TROUGH SITUATED ACROSS NORTHERN GA...CENTRAL AL AND SOUTHEAST MS. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN THE BASE OF THE TROUGH THIS AFTERNOON...AND CONTINUE TO APPROACH WESTERN GA. THE LATEST RUN OF THE HRRR HAS THE ACTIVITY FROM THE WEST CONGEALING WITH THE SE ACTIVITY LATE THIS AFTERNOON. ACTIVITY SHOULD DECREASE IN STRENGTH AND COVERAGE WITH THE LOSS OF HEATING FOR THE EARLY EVENING HOURS. FOR OVERNIGHT...WV LOOP SHOWS A GOOD PIECE OF SHORTWAVE ENERGY DROPPING SE IN THE FLOW ACROSS W KY THIS AFTERNOON. MODELS DO DEVELOP SCT ACTIVITY MAINLY ACROSS NORTHERN GA OVERNIGHT. WITH SOME MARGINAL INSTABILITY PRESENT OVERNIGHT...SCT SHRA/TSRA SEEM VERY REASONABLE. THE 500MB TROUGH AXIS IS PROGGED TO BE ACROSS THE CENTRAL CWFA DURING THE DAY TOMORROW. THIS SHOULD LEAD TO A LITTLE MORE COVERAGE OF STORMS ACROSS THE REGION. PWATS REMAIN THE SAME ACROSS NORTHERN GA...BUT WILL CREEP UP TO AROUND 2 INCHES ACROSS THE CENTRAL AND SOUTHERN CWFA. IN ADDITION...BL WINDS REMAIN VERY LIGHT (AOB 15K)...SO MOVEMENT OF STORMS WILL BE VERY SLOW OR NEARLY STATIONARY. EVEN THOUGH THE ATMOS WILL BE MARGINALLY UNSTABLE AT THE SURFACE...MID LEVEL LAPSE RATES AND SHEAR REMAIN VERY WEAK. THE POTENTIAL FOR SEVERE WEATHER REMAINS LOW...BUT STRONG THUNDERSTORMS ARE POSSIBLE...WITH AN ISOLATED SEVERE STORM NOT OUT OF THE QUESTION. NLISTEMAA LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... DIURNAL CONVECTION EXPECTED TO CONTINUE ACROSS THE AREA EACH AFTERNOON AND EVENING THROUGH DAY 7. MODELS IN GOOD AGREEMENT WITH SURFACE RIDGE LOSING ITS GRIP ON THE SOUTHEAST BY WEEKS END. THEY ARE ALSO IN GOOD AGREEMENT WITH THE UPPER LEVEL RIDGE BUILDING AND REMAINING OVER THE WESTERN US AS LONG WAVE TROUGH SETS UP OVER THE EAST COAST BY FRIDAY. WITH THE EASTERN EXTENT OF THE UPPER LEVEL RIDGE MORE LIMITED THAN PREVIOUSLY EXPECTED...HAVE COOLED EXTENDED HIGH TEMPERATURES A DEGREE OR TWO. STILL LOOKING FOR HIGHS IN THE UPPER 80S AND LOW 90S. HAVE INCREASED POPS SOMEWHAT FOR THE WEEKEND...AND EXPECT THIS UPWARD TREND IN THE FORECAST TO CONTINUE IN THE COMING DAYS. ENHANCED MOISTURE ACROSS THE REGION AS A RESULT OF THE UPPER LEVEL TROUGH AND ASSOCIATED FRONTAL BOUNDARY SHOULD SUPPORT MORE SIGNIFICANT COVERAGE OF PRECIP ACTIVITY. ANTICIPATE FRONTAL PASSAGE BY EARLY NEXT WEEK...WITH DROP IN POPS AND SLIGHTLY COOLER TEMPERATURES IN STORE AS A RESULT. 31/01 && .AVIATION... 06Z UPDATE... ANOTHER SHORT WAVE WILL MOVE ACROSS THE FORECAST AREA THIS AFTERNOON BRINGING SCATTERED TO NUMEROUS THUNDERSTORMS TO THE FORECAST AREA...MAINLY AFTER 20Z. HIGHEST CHANCE WILL BE IN THE AHN/MCN/CSG. WINDS WILL BE LIGHT WEST THROUGH THE FORECAST. CURRENT ALL CIGS VFR BUT EXPECT MVFR CIGS TO DEVELOP THIS MORNING. AREAS OF FOG ARE EXPECTED TO DEVELOP THIS MORNING...ESPECIALLY IN AREAS THAT HAD RAINFALL YESTERDAY. SOME VSBYS COULD DROP TO IFR BUT MOST SHOULD STAY MVFR. //ATL CONFIDENCE...06Z UPDATE... MEDIUM-LOW ON CIGS THIS MORNING. HIGH ON OCCURRENCE OF CONVECTION TODAY...MEDIUM ON IMPACTS TO ATL. HIGH ON ALL REMAINING ELEMENTS. 17 && .PRELIMINARY POINT TEMPS/POPS... ATHENS 69 87 69 90 / 30 50 30 30 ATLANTA 70 86 71 88 / 30 50 30 30 BLAIRSVILLE 64 81 64 86 / 40 50 20 40 CARTERSVILLE 69 88 69 89 / 20 50 20 30 COLUMBUS 71 91 72 92 / 50 40 30 30 GAINESVILLE 68 85 70 87 / 20 50 30 30 MACON 71 89 71 90 / 60 50 30 30 ROME 68 89 69 91 / 20 40 10 30 PEACHTREE CITY 69 87 69 88 / 30 50 30 30 VIDALIA 72 88 73 92 / 50 50 30 30 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
243 AM CDT TUE JUN 25 2013 .DISCUSSION... ISSUED 240 AM CDT TUE JUN 25 2013 SHORT TERM...TODAY THROUGH WEDNESDAY... MAIN CONCERNS IN THIS PERIOD ARE WITH SEVERE WEATHER POTENTIAL... ESPECIALLY ON WEDNESDAY. DAY1 CONVECTIVE OUTLOOK SHOWS THE SLIGHT RISK FROM ABOUT I-72 NORTHWARD TODAY. LATEST IN THE SERIES OF NOCTURNAL MCS SYSTEMS WAS TRACKING ALONG THE ILLINOIS/WISCONSIN BORDER AT 2 AM. WHILE HIGHER RESOLUTION MODEL GUIDANCE KEEPS THE TRACK OF THIS WELL TO OUR NORTH...RADAR MOSAICS STARTING TO SHOW THE OUTFLOW BOUNDARY DROPPING SOUTHWARD THROUGH NORTHERN ILLINOIS. THE AIR TO THE SOUTH WILL BECOME QUITE UNSTABLE LATER TODAY WITH CAPES OF OVER 3000 J/KG. ANOTHER MCS PROGGED TO DEVELOP TO THE NORTHWEST AS A SHORTWAVE MOVES IN FROM THE PLAINS...WITH THIS MCS SLIDING ACROSS THE NORTH HALF OF ILLINOIS LATER TODAY. HIGHER PROBABILITIES ARE FOCUSED MORE ON THE I-80 CORRIDOR. STORMS THAT DO FORM WILL AGAIN HAVE THE POTENTIAL FOR HEAVY RAIN...WITH PRECIPITABLE WATER VALUES OF AROUND 1.8 INCHES. SPC PROBABILITY GRAPHICS FOR THE DAY2 OUTLOOK SHOW A SEVERE WEATHER THREAT OVER ALL OF OUR AREA BUT FOCUS ON LOCATIONS ALONG AND EAST OF I-57 WITH THE HIGHEST THREAT FOR SEVERE WEATHER ON WEDNESDAY...INCLUDING VERY LARGE HAIL AND DAMAGING WINDS. COLD FRONT SHOULD BE CROSSING THE STATE DURING THE AFTERNOON. AIR MASS WILL BE EXTREMELY UNSTABLE AHEAD OF IT...WITH CAPES OF AROUND 4500 J/KG AND 0-6KM BULK SHEAR OF 30-40 KNOTS. PRECIPITABLE WATER VALUES OF AROUND 1.8 INCHES POINT TO POTENTIAL FOR HEAVY RAIN ONCE AGAIN...BUT HOPEFULLY THE STORMS ON WEDNESDAY WILL BE MORE PROGRESSIVE AS COMPARED TO THE LAST FEW DAYS. HIGH TEMPERATURE FORECASTS THE LAST FEW DAYS HAVE BEEN A REAL STRUGGLE WITH ALL OF THE CONVECTION IN THE AREA. HAVE SCALED BACK HIGHS A COUPLE DEGREES...GOING CLOSER TO A MET/MAV BLEND. IF THE CONVECTION TODAY IS MORE ISOLATED...THEN THE WARMER MAV NUMBERS SHOULD BE ATTAINABLE. LONG TERM...THURSDAY THROUGH MONDAY... INITIAL COLD FRONT ON WEDNESDAY WILL BE A BIT OF A TEASE...WITH VERY WARM AND HUMID CONDITIONS CONTINUING INTO THURSDAY. A STEADY PUSH OF COOLER AIR SHOULD BEGIN TO SPREAD IN ON FRIDAY AS AN UPPER LOW OVERSPREADS THE GREAT LAKES...AND STARTS A PERSISTENT NORTHWEST FLOW OVER THE MIDWEST. BOTH THE GFS AND ECMWF MODELS SHOW A SIGNIFICANT UPPER TROUGH BEING CARVED OUT OVER THE MIDWEST AND LOWER MISSISSIPPI VALLEY THIS WEEKEND...WITH THE LATTER MODEL A BIT MORE PERSISTENT AND LASTING THROUGH EARLY NEXT WEEK. TEMPERATURES WILL BE SEVERAL DEGREES BELOW NORMAL...BUT NOT ABNORMALLY OUT OF LINE FOR THE END OF JUNE. BLENDED MODEL GUIDANCE SHOWS SLIGHT CHANCE POPS FOR MUCH OF THE FRIDAY THROUGH MONDAY PERIOD. WITH THE COLDER AIR ALOFT AND THE DEEP TROUGH OVERHEAD...AM RELUCTANT TO COMPLETELY REMOVE RAIN CHANCES...ALTHOUGH THEY WOULD BE MORE DIURNAL IN NATURE. GEELHART && .AVIATION... ISSUED 1204 AM CDT TUE JUN 25 2013 TEMPO IN FOR TSRA BETWEEN 09 AND 14Z AS THE NAM IS SIGNALING A SOUTHERLY PUSH TO THE CONVECTION CURRENTLY OVER SE WI. WITH HRRR AND RUC BOTH DRY AND THE MODEL PERFORMANCE ABYSMAL WITH THE MCS TRAIN OF LATE...FORECAST CONFIDENCE IS LOW BUT TREND/PERSISTENCE BASED. THE LATEST 4KM WRF KEEP CONVECTION AWAY UNTIL MIDDAY. SOUTHERLY COMPONENT TO THE LINE OF STORMS TO THE NORTH ARE DRIVING THE NEXT 6 HRS. VCTS FROM MID MORNING ON THROUGH THE FORECAST AS THE ENTIRE 24 HRS HINGES ON MESOSCALE BOUNDARY INTERACTIONS AND REMNANT MCVS. AHEAD OF STORMS...VFR CONTINUES...AS WELL AS RAPID CLEARING BEHIND THEM. TOMORROW EXPECTED TO BE BUSY AGAIN WITH THUNDER WIDESPREAD ACROSS THE AREA. THOUGH TIMING INDIVIDUAL CELLS/TERMINALS IS VERY PROBLEMATIC. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1210 AM CDT TUE JUN 25 2013 .DISCUSSION... ISSUED 855 PM CDT MON JUN 24 2013 ANOTHER MCS EXITING THE CWA THIS EVENING...LEAVING A COOLER AND MORE HUMID BOUNDARY LAYER IN ITS WAKE. WILL BE ADJUSTING THE HOURLY TEMPS AND OVERNIGHT LOWS AS WELL AS SOME OF THE AREA WILL BE SEEING THEIR LOWS NOW...IN THE REMAINING COLD AIR FROM CONVECTION. SOUTHERLY WINDS WILL BRING IN WARMER TEMPS FROM THE SOUTH TO COUNTER ANY ADDITIONAL RADIATIONAL COOLING AFTER SUNSET. WILL WATCH CLOSELY FOR DEVELOPMENT OF FOG...BUT SHOULD REMAIN PATCHY IF IT DEVELOPS. ADDITIONAL SHOWER ACTIVITY REMAINING TO THE NORTH IN HRRR AND THE RUC...BUT WITH SO MANY BOUNDARIES OUT THERE FROM DYING CONVECTION...WILL MAINTAIN A LOW POP OVERNIGHT AFTER 06Z. && .AVIATION... ISSUED 1204 AM CDT TUE JUN 25 2013 TEMPO IN FOR TSRA BETWEEN 09 AND 14Z AS THE NAM IS SIGNALING A SOUTHERLY PUSH TO THE CONVECTION CURRENTLY OVER SE WI. WITH HRRR AND RUC BOTH DRY AND THE MODEL PERFORMANCE ABYSMAL WITH THE MCS TRAIN OF LATE...FORECAST CONFIDENCE IS LOW BUT TREND/PERSISTENCE BASED. THE LATEST 4KM WRF KEEP CONVECTION AWAY UNTIL MIDDAY. SOUTHERLY COMPONENT TO THE LINE OF STORMS TO THE NORTH ARE DRIVING THE NEXT 6 HRS. VCTS FROM MID MORNING ON THROUGH THE FORECAST AS THE ENTIRE 24 HRS HINGES ON MESOSCALE BOUNDARY INTERACTIONS AND REMNANT MCVS. AHEAD OF STORMS...VFR CONTINUES...AS WELL AS RAPID CLEARING BEHIND THEM. TOMORROW EXPECTED TO BE BUSY AGAIN WITH THUNDER WIDESPREAD ACROSS THE AREA. THOUGH TIMING INDIVIDUAL CELLS/TERMINALS IS VERY PROBLEMATIC. HJS && .PREV DISCUSSION... ISSUED 300 PM CDT MON JUN 24 2013 THE SHORT TERM THROUGH WEDNESDAY WILL BE DOMINATED BY PERIODIC BOUTS OF SEVERE STORMS AND FLASH FLOODING...ALONG WITH HIGH HEAT AND HUMIDITY. A COLD FRONT SHOULD PUSH ACROSS ILLINOIS LATE IN THE WEEK PROVIDING SOME RELIEF FROM THE HEAT AND HUMIDITY AND DAILY THUNDERSTORMS. MUCH MORE COMFORTABLE CONDITIONS SHOULD DEVELOP NEXT WEEKEND. BASED ON THE 3-5" OF RAIN FROM PEORIA AND NORTH...WE DECIDED TO INCLUDE OUR NORTHERN 5 COUNTIES IN A FLASH FLOOD WATCH THROUGH TONIGHT DUE TO THE HEAVY RAIN POTENTIAL AGAIN. SHORT TERM...TONIGHT THROUGH WEDNESDAY. INITIAL SEVERE STORM WATCH IS IN EFFECT UNTIL 7 PM FOR OUR WESTERN COUNTIES BUT ANOTHER WATCH FOR AREAS NORTHEAST OF THAT WATCH MAY BE COMING SOON. BASED ON RADAR ANALYSIS...THE SOUTHERN END OF THE LINE OF STORMS IN N MO AND E IOWA APPEARS TO BE ERODING EARLY ON. WE COULD SEE ADDITIONAL DEVELOPMENT ON THE SOUTHERN FLANK AIDED BY INCREASING MID-LEVEL FLOW AND MOISTURE CONVERGENCE. IF NOT...THE SOUTHERN COUNTIES IN THE WATCH WILL NOT BE AFFECTED AS MUCH WITH THIS ROUND OF STORMS. CORFIDI VECTORS ARE SHOWING THE LINE SHOULD MAINTAIN ITS MOTION TO THE EAST-NORTHEAST AS IT MOVES ACROSS IL...WHICH WILL MAKE IT MU-CAPE VALUES ARE CLIMBING TO NEAR 3000 J/KG AS SUNSHINE AHEAD OF THE LINE HAS HELPED BOOST SURFACE TEMPERATURES INTO THE UPPER 80S WITH SURFACE DEWPOINTS IN THE LOWER 70S. SURFACE BASED CONVECTION WILL AID IN DOWNBURST WINDS BEING ABLE TO REACH THE GROUND. SPC MESO-ANALYSIS SHOWS DOWNBURST CAPE VALUES AROUND 1100 J/KG...WHICH ALSO POINTS TOWARD EFFICIENT MOMENTUM TRANSFER TO THE SURFACE AND DAMAGING WINDS. WITH VGP ABOVE 0.2 ACROSS OUR NORTHERN COUNTIES...WE COULD SEE SOME ROTATING EMBEDDED SUPERCELLS WITH A TORNADO POSSIBLE. THE LINE OF STORMS SHOULD REACH OUR WESTERN COUNTIES AROUND 4 PM...AND PROGRESS EASTWARD TO NEAR BMI BY 6 PM AND INTO INDIANA BY 8-9 PM. STRATIFORM RAIN BEHIND THE LINE MAY LINGER FOR A FEW HOURS. SATELLITE IMAGES SHOW A WEAK SHORTWAVE IN THE WAKE OF THIS COMPLEX...SO A FEW ADDITIONAL THUNDERSTORMS MAY AFFECT OUR NW COUNTIES THROUGH MORNING. THEREFORE WE KEPT CHANCE POPS IN THE NW AFTER MIDNIGHT. ANOTHER ROUND OF SEVERE STORMS WILL BE POSSIBLE ON TUESDAY...MAINLY NORTH OF I-72/74-DANVILLE. WE ORIGINALLY HAD EXPECTED SOME UPPER LEVEL RIDGING TO PROVIDE A BREAK IN THE STORMS...AND WE STILL MAY SEE DRY CONDITIONS FOR MUCH OF THE DAY. HOWEVER...SPC HAS EXPANDED THE DAY 2 SLIGHT RISK FARTHER SOUTH TO INCLUDE A LARGE PORTION OF OUR FORECAST AREA...SO WE DECIDED TO ACKNOWLEDGE THE SEVERE POTENTIAL WITH SLIGHTLY HIGHER POPS. WE WILL HAVE A BETTER CHANCE OF BEING CAPPED TUES AS THE MID LEVELS WARM. HOWEVER...ISOLATED AREAS THAT DO BREAK THE CAP WILL HAVE A GREAT DEAL OF ML-CAPE FOR VIGOROUS UPDRAFTS. WE STILL MAINLY HAVE SLIGHT CHANCE POPS EXCEPT FOR NORTH OF I-74 WHERE WE WENT WITH CHANCE POPS. WEDNESDAY SHOULD SEE INCREASING BETTER DESTABILIZATION OF THE LOWER TROP AS THE UPPER RIDGE BEGINS TO BREAK DOWN IN RESPONSE TO A PROGRESSIVE TROUGH FROM CANADA. SURFACE HEAT AND HUMIDITY WILL REMAIN HIGH...BUT SUNSHINE MAY BE A BIT MORE LIMITED IF CONVECTION DEVELOPS EARLIER IN THE AFTERNOON. TUES AND WED WILL HAVE POTENTIAL FOR HEAT INDEX READINGS AROUND 100 IN MANY AREAS BASED ON THE AMOUNT OF SUNSHINE AND WHERE THE CIRRUS SHIELD DEVELOPS AHEAD OF CONVECTION. STILL...VERY UNCOMFORTABLE CONDITIONS. LONG TERM...THURSDAY THROUGH MONDAY. THE MODELS ALL SHOW A COLD FRONTAL PASSAGE AT SOME POINT BEGINNING LATE WED NIGHT OR THURSDAY...BUT THE ARRIVAL OF COLDER AIR DELAYED UNTIL FRIDAY INTO FRIDAY NIGHT AS A SECONDARY PUSH OF CANADIAN AIR OCCURS. WE MAY SEE A FEW SHOWERS OR STORMS IN THE EAST THURSDAY AS THE COLD FRONT DEPARTS...WITH A BREAK IN THE RAIN LATER THURS AND THURS NIGHT. AS A REINFORCING SHORTWAVE IN THE 500 MB TROUGH ROUNDS THE BACK SIDE OF THE SYSTEM...IT IS PROJECTED TO BECOME CUT OFF AND LINGER ACROSS THE WESTERN GREAT LAKES THROUGH EARLY NEXT WEEK. THAT WOULD LIKELY KEEP RAIN SHOWER CHANCES ACROSS OUR AREA FOR MUCH OF THAT TIME...AS THE COLD POOL PROVIDES FAVORABLE LAPSE RATES FOR UPDRAFTS. SO A CHANGE FROM HEAT AND HUMIDITY TO CLOUDY AND COOLER APPEARS IN THE OFFING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
1137 PM CDT MON JUN 24 2013 ...UPDATED FOR AVIATION... .SYNOPSIS... ISSUED AT 353 PM CDT MON JUN 24 2013 A FAIRLY STRONG SHORTWAVE TROUGH BY LATE JUNE STANDARDS WAS APPROACHING THE SOUTHERN AND CENTRAL HIGH PLAINS THIS AFTERNOON. AHEAD OF THIS FEATURE, STRONG SURFACE TROUGH HAD DEVELOPED OVER THE HIGH PLAINS, WITH STRONG SOUTHERLY WINDS ACROSS SOUTHWEST KANSAS. ELEVATED CONVECTION IN ADVANCE OF THIS SYSTEM DEVELOPED THIS MORNING EAST OF DODGE CITY AND THEN MOVED EAST AND WEAKENED. ANOTHER BATCH OF ELEVATED CONVECTION DEVELOPED WEST OF A SURFACE DRYLINE IN SOUTHEAST COLORADO AND MOVED INTO FAR SOUTHWEST KANSAS THIS AFTERNOON. SURFACE BASED CONVECTION HAD NOT YET DEVELOPED AS OF 3 PM. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 353 PM CDT MON JUN 24 2013 THE SHORT RANGE HRRR DOES INDICATE STORMS DEVELOPING IN THE TEXAS AND OKLAHOMA PANHANDLES THIS AFTERNOON AS UPPER LEVEL FORCING AIDS IN LOW LEVEL CONVERGENCE ALONG THE DRYLINE. GIVEN THE FAIRLY STRONG MID LEVEL FLOW FROM THE SOUTHWEST, THIS CONVECTION SHOULD MOVE NORTHEASTWARD FAIRLY RAPIDLY INTO SOUTHWEST KANSAS THIS EVENING. SURFACE BASED CAPE VALUES WERE APPROACHING 3000 J/KG FROM THE TEXAS PANHANDLE INTO SOUTHWEST KANSAS AHEAD OF THE DRYLINE. 0-6 KM BULK SHEAR WAS APPROACHING 40 KTS IN THIS SAME AREA, BUT LOW LEVEL SHEAR WAS VERY WEAK. GIVEN THE EXPECTED HIGH DEWPOINT DEPRESSIONS AND RESULTANT HIGH CLOUD BASES, THE STORMS MAY DEVELOP QUITE A BIT OF OUTFLOW, AND THIS MAY LIMIT THE SEVERITY AS FAR AS HAIL SIZE IS CONCERNED (SINCE THE STORMS MAY NOT REMAIN AS SUPERCELL STRUCTURES AS LONG). BUT HAIL AS LARGE AS GOLFBALLS IS POSSIBLE WITH THE STRONGEST STORMS. IT IS UNCLEAR HOW ORGANIZED THE STORMS WILL BE AND HOW WIDESPREAD AND HEAVY THE RESULTANT RAINFALL WOULD BE. BUT STORM CHANCES WERE INCREASED TO 30-40% FOR PARTS OF SOUTHWEST KANSAS INCLUDING DODGE CITY, JETMORE AND LARNED GIVEN THE SIGNIFICANT FORCING AND SURFACE BASED CAPE. AFTER THE AFOREMENTIONED SHORTWAVE TROUGH PASSES TONIGHT AND WITH THE LOSS OF DAYTIME HEATING, STORM CHANCES WILL DIMINISH RAPIDLY BY LATE EVENING. THE LOW LEVEL WINDS WILL BEGIN TO VEER AS WELL AND THIS WILL RESULT IN THE AXIS OF DEEP MOISTURE SHIFTING EASTWARD. SOUTHWEST WINDS AT 15 KTS EVEN LATE TONIGHT WILL PREVENT TEMPERATURES FROM DROPPING BELOW THE LOWER 70S AT DODGE CITY, HAYS AND PRATT, WITH ONLY SLIGHTLY COOLER READINGS NEAR THE COLORADO BORDER. BEHIND THE SHORTWAVE TROUGH, A WEAK COLD FRONT WILL PROGRESS INTO CENTRAL KANSAS TUESDAY AFTERNOON, WITH A TRAILING DRYLINE EAST OF DODGE CITY AND INTO THE PANHANDLES. VERY HOT TEMPERATURES FROM 103 TO 106F ARE EXPECTED IMMEDIATELY BEHIND THE DRYLINE WHERE THE LOW LEVEL AIR HAS MOVED DOWNSLOPE AND WARMED ADIABATICALLY. ONLY SLIGHTLY COOLER AIR CAN BE EXPECTED IN FAR WESTERN KANSAS ON THE HIGHER TERRAIN, AND BEHIND THE WEAK COLD FRONT FROM WAKEENEY TO DIGHTON. THUNDERSTORMS ARE NOT EXPECTED TUESDAY AFTERNOON GIVEN THE LACK OF FORCING IN THE WAKE OF THE SHORTWAVE TROUGH AND SINCE THE LOW LEVEL MOIST AXIS WILL HAVE SHIFTED FURTHER EAST BY THE TIME OF PEAK HEATING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 336 PM CDT MON JUN 24 2013 ZONAL FLOW ALOFT WILL BE IN PLACE OVER THE LOWER 48 STATES AT THE BEGINNING OF THE EXTENDED PERIOD. A SHORTWAVE TROUGH THAT IS NOW MOVING THROUGH THE GREAT BASIN AND DESERT SOUTHWEST WILL BE EXITING THE NORTHERN AND CENTRAL PLAINS TUESDAY EVENING. THIS SYSTEM WILL BRING A WEAK FRONTAL BOUNDARY SOUTH ACROSS WESTERN KANSAS IN ITS WAKE LATE TUESDAY AFTERNOON AND EVENING. PRECIPITATION CHANCES LOOK FAIRLY SMALL GIVEN THE LACK OF UPPER SUPPORT AND A FAIRLY DRY AIRMASS. THROUGH THE MIDDLE PART OF THE WEEK, 500 MILLIBAR HEIGHTS WILL BE BUILDING OVER THE WESTERN AND CENTRAL PART OF THE COUNTRY. WITH INCREASING THICKNESS VALUES OVER WESTERN KANSAS WE SHOULD SEE DAYTIME HIGH TEMPERATURES WARMING BACK UP TO AROUND OR ABOVE 100 DEGREES ESPECIALLY BY THURSDAY. THE UPPER RIDGE BECOMES MORE AMPLIFIED OVER WESTERN NORTH AMERICA TOWARD THE UPCOMING WEEKEND WITH UPPER LEVEL FLOW BECOMING MORE NORTHWESTERLY OVER THE CENTRAL PLAINS. A WEAK FRONTAL BOUNDARY IS FORECAST TO MOVE SOUTH THROUGH THE CENTRAL HIGH PLAINS EARLY FRIDAY WITH EASTERLY UPSLOPE FLOW SETTING UP INTO THE EASTERN SLOPES OF THE ROCKIES. AFTERNOON THUNDERSTORMS SHOULD DEVELOP OFF THE FRONT RANGE. GIVEN THE UPPER LEVEL FLOW, SOME OF THESE COULD MOVE INTO FAR WESTERN KANSAS FRIDAY EVENING. THE UPPER LEVEL FLOW OVER THE CENTRAL PART OF THE COUNTRY BECOMES EVEN MORE MERIDIONAL THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THE MEDIUM RANGE MODELS HAVE ALL BEEN TRENDING IN THIS DIRECTION THROUGH THE PAST FEW RUNS. THINK THAT THE CURRENT WEEK TWO OUTLOOK SHOULD BE TRENDED BACK TO AT LEAST NEAR NORMAL TEMPERATURES FOR NOW BUT BASED ON FORECAST TEMPERATURES, WE COULD BE EVEN COOLER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1133 PM CDT MON JUN 24 2013 EXPECT VFR CONDITIONS THROUGH THE PERIOD. A DRYLINE TROUGH WILL MOVE ACROSS WESTERN KANSAS AFTER 12Z WITH SOUTH WINDS SHIFTING TO THE SOUTH BUT DECREASING IN THE TROUGH AXIS. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 105 69 101 / 10 0 0 0 GCK 72 104 65 101 / 10 0 0 0 EHA 70 103 66 101 / 10 0 0 0 LBL 74 105 68 104 / 10 0 0 0 HYS 74 104 70 101 / 20 0 0 0 P28 74 100 74 101 / 20 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...FINCH SHORT TERM...FINCH LONG TERM...GERARD AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
524 AM EDT TUE JUN 25 2013 .SYNOPSIS... STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE EXPECTED TODAY AS A FRONTAL BOUNDARY SAGS SOUTHWARD ACROSS THE AREA. UNSETTLED CONDITIONS WILL PERSIST THROUGH THE REMAINDER OF THE WEEK AND UPCOMING WEEKEND AS A BROAD AND SLOW MOVING LOW PRESSURE SYSTEM FROM THE GREAT LAKES MOVES EASTWARD.&& .NEAR TERM /THROUGH TONIGHT/... UPDATE 0520L: FEW INITIAL SHOWERS/TSTM INTO XTRM NRN AND WRN MAINE ATTM... ADJUSTED POPS/HRLY TEMPS TO BETTER FIT CURRENT AND EXPECTED TRENDS NXT FEW HRS... QUIET ACROSS THE FA FOR NOW AS WEAKENING BAND OF SHOWERS HAS EXITED OUR SERN AREAS WHILE ANOTHER CLUSTER OF SHOWERS AND TSTMS IS NOTED NW-N OF THE FA ALONG AND JUST W OF THE ST LAWRENCE... NR STATIONARY FRONTAL BNDRY N OF THE REGION XTNDG WNW-ESE FROM JAMES BAY ACROSS THE GASPE AND INTO THE GULF OF THE ST LAWRENCE. SEVERAL WEAK LOWS CONT TO SLIDE ESEWRD ALONG THIS BNDRY W/ THE STRONGEST OF THESE NR THE SERN TIP OF JAMES BAY ATTM. MODELS IN FAIRLY GOOD AGREEMENT AND ALLOW THIS SFC LOW NR JAMES BAY TO DROP SEWRD ALONG THIS FRONTAL BNDRY W/ THE FRONTAL BNDRY SAGGING SWRD ACROSS THE AREA FROM LATE TDY THRU TNGT. VRY WARM/HUMID AND UNSTABLE AIR IN PLACE ACROSS THE AREA S OF THIS BNDRY W/ SBCAPES FCST FROM 1000-2500 J/KG AND THIS WILL COMBINE W/ STRONG SFC AND UPPER DYNAMICS AS THIS FRONTAL BNDRY AND LOW PRES SAG SEWRD TOWARDS THE AREA LATER TDY TO PRODUCE THE THREAT OF STRONG TO PSBLY SEVERE TSTMS ACROSS THE AREA. CURRENTLY THE SPC HAS ALL BUT OUR DOWNEAST AREAS IN A SLIGHT RISK FOR SVR W/ DAMAGING WNDS THE PRIMARY THREAT. INITIAL ACTIVITY NW-N OF THE AREA IS FCST BY THE SHORTER TERM MODEL GUIDANCE LIKE THE HRRR AND RUC TO WEAKEN AND DISSIPATE AS IT REACHES OUR FAR NRN AREAS ERLY THIS AM BUT NOT SURE ABOUT THIS... IN ANY CASE...APPEARS STRONGER ACTIVITY WILL DVLP LATER THIS AM THRU THE AFTN HRS W/ HGHST POPS ACROSS THE N AND E CENTRAL AREAS IN TO THE EVE HRS W/ LOWEST POPS FAR SW. WILL CARRY MENTION OF SVR ALONG W/ ENHANCED WORDING FOR HVY RAIN/DAMAGING WNDS AND SMALL HAIL... FOR TNGT...GUIDANCE SUGGESTS THIS BNDRY WILL BE JUST S AND W OF THE FA BY ERLY WED W/ WEAK LOW PRES CNTRS OVR ERN NS...SRN MAINE AND SWRN QUEBEC. HIGH PRES W/ SOME DRIER AIR MAY TRY TO NUDE INTO FAR NERN AREAS BY LATE TNGT/ERLY WED... EXPECT ANOTHER WARM AND MUGGY DAY TDY W/ HIGH TEMPS LARGELY DEPENDENT ON CLD CVR. THINKING THERE WILL BE SOME SUN N AND NE W/ MORE PREVALENT SUNSHINE S AND W. WILL ADVERTISE HIGHS INTO THE LOWER 80S N W/ NR 90 PSBL SRN AREAS AWAY FROM THE COAST. ANOTHER WARM AND MUGGY NGT TNGT ACROSS RN AND WRN AREAS W/ SOME COOLER AND DRIER AIR LIKELY WORKING INTO NERN AREAS. PLENTY OF LOW LEVEL MOISTURE AND RATHER LGT WNDS SUGGESTS THE THREAT OF FOG TNGT ACROSS MUCH OF THE REGION...&& .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AN H5 UPPER LOW DEEPENS ACROSS THE GREAT LAKES REGION DURING THIS TIME FRAME. THIS WILL ALLOW AMPLE MOISTURE TO MOVE INTO NORTHERN NEW ENGLAND. EXPECT PERIODS OF SHOWERS BOTH DAYS. HIGHS WILL BE NEAR NORMAL ON WEDNESDAY AND MUCH BELOW NORMAL ON THURSDAY. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AN H5 UPPER LOW SLOWLY PROGRESSES INTO THE NORTHEAST U.S. LATE THIS WEEK AND THEN LIFTS INTO QUEBEC THIS WEEKEND. THIS ALLOWS THE DAMP WEATHER PATTERN TO PERSIST. THURSDAY NIGHT AND FRIDAY ARE FORECAST TO BE PARTICULARLY WET WITH PERIODS OF RAIN. TEMPERATURES WILL GRADUALLY WARM BACK TO SEASONAL LEVELS BY THE WEEKEND. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... NEAR TERM: PATCHY FOG ERLY THIS AM MAY RESULT IN SOME MVFR TO IFR CONDS UP UNTIL OR SHORTLY AFTER SUNRISE. MAINLY VFR CONDS ARE THEN EXPECTED OUTSIDE OF ANY SHOWERS/TSTMS W/ MVFR/IFR DURING THIS ACTIVITY. PATCHY TO AREAS OF FOG EXPECTED AGAIN TNGT ALONG W/ A THREAT OF SHOWERS MAINLY ACROSS THE SRN HALF OF THE FA. SHORT TERM: MVFR AND POSSIBLY IFR CIGS AND VSBYS ARE EXPECTED AT TAF SITES WITH SHOWERS...RAIN AND FOG. && .MARINE... NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY FOG TODAY...THEN IN AREAS OF FOG AND ANY SHOWERS/THUNDERSTORMS LATER TODAY AND TONIGHT. SHORT TERM: NO HEADLINES ARE FORECAST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...KHW SHORT TERM...OKULSKI LONG TERM...OKULSKI AVIATION...KHW/OKULSKI MARINE...KHW/OKULSKI
AREA FORECAST DISCUSSION
NWS GRAY ME
329 AM EDT TUE JUN 25 2013 .SYNOPSIS... HOT AND HUMID AIR CONTINUES TO BE PUSHED NORTH INTO NEW ENGLAND AS SOUTHWEST FLOW PERSISTS OVER THE AREA. THE THREAT FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE. BY THURSDAY AND FRIDAY THERE IS A CHANCE FOR A MORE CONSISTENT RAIN AS WEAK LOW PRESSURE DEVELOPS TO OUR WEST AND LIFTS NORTHEAST INTO QUEBEC. THIS WILL ALSO SHIFT THE WINDS MORE ONSHORE...WITH COOLER TEMPERATURES AT THE END OF THE WEEK...ALTHOUGH HUMIDITY`S WILL NOT DROP OFF THAT MUCH. WE WILL SWITCH BACK TO A SOUTHERLY FLOW FOR THE WEEKEND...WITH WARMER AND CONTINUED HUMID CONDITIONS. && .NEAR TERM /THROUGH TODAY/... ..."SUPERMOON" TIDES REACHED 12 FEET IN PORTLAND EARLY THIS MORNING... LATEST HRRR RUN CONTINUES TO INDICATE CONVECTIVE INITIATION BEGINNING AROUND 18Z OVER FAR NORTHERN AND WESTERN PORTIONS OF THE FORECAST AREA. THIS IS IN RESPONSE TO SHORT WAVE RACING ACROSS SOUTHERN CANADA. WIND FIELDS WILL BE INCREASING (AND UNIDIRECTIONAL) WITH THIS FEATURE. WITH STEEP LOW LEVEL LAPSE RATES AND HIGH SURFACE DEW POINTS IN PLACE...CONVECTION TODAY WILL BE MORE ORGANIZED THAN YESTERDAY AS THE WIND MAX APPROACHES FROM THE NORTHWEST. DAMAGING STRAIGHT LINE WINDS ARE POSSIBLE IN ISOLATED STORMS...WITH LARGE HAIL POSSIBLE IN ANY OF THE STRONGER STORMS AS CAPE VALUES RAPIDLY CLIMB WITH GOOD SOLAR HEATING TODAY. HAVE ENHANCED WORDING IN THE GRIDS. PRECIPITABLE WATER VALUES REMAIN VERY HIGH. SOME OF THE SHOWERS AND STORMS MAY DROP VERY HEAVY RAIN IN A SHORT PERIOD OF TIME. STORMS WILL BE RELATIVELY FAST MOVING...BUT TRAINING OF SHOWERS WILL NEED TO BE MONITORED. AN AIR QUALITY ALERT WILL REMAIN IN EFFECT FOR TODAY...UNTIL 11 PM. && .SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/... WITH LOW LEVEL MOISTURE IN PLACE...AFTER AFTERNOON AND EVENING RAINS...PATCHY FOG WILL DEVELOP ONCE AGAIN ACROSS THE REGION TONIGHT. USED A BLEND OF MAV/MET MOS FOR OVERNIGHT MIN TEMPERATURES. MORE SHOWERS AND STORMS ARE POSSIBLE WEDNESDAY AFTERNOON AS A BACKDOOR COLD FRONT MOVES SOUTH ACROSS MAINE AND NEW HAMPSHIRE. SOME OF THESE STORMS MAY BE LOCALLY STRONG AS WELL. READINGS OVER SOUTHERN NEW HAMPSHIRE WILL SHOOT UP QUICKLY AHEAD OF THE SURFACE COLD FRONT...SO A HEAT WAVE (3 CONSECUTIVE DAYS AT OR ABOVE 90 DEGREES) IS STILL POSSIBLE OVER THIS REGION. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... THE MODELS ARE IN DECENT AGREEMENT WELL INTO NEXT WEEK ON EVOLVING LONGWAVE PATTERN. A SERIES OF SHORTWAVES RIDING OVER THE TOP OF THE WESTERN CONUS RIDGE WILL CARVE OUT A DEEP TROUGH ACROSS THE EAST BY THE UPCOMING WEEKEND. THE OVERALL THEME WILL BE WARM...HUMID...AND WET FOR THE FORECAST PERIOD. IN THE DAILIES...LOW PRESSURE WILL MOVE EAST FROM THE GREAT LAKES ON THURSDAY THEN SLOW DOWN AND LINGER ACROSS THE NORTHEAST THROUGH EARLY NEXT WEEK PRODUCING WARM, HUMID, AND WET WEATHER ACROSS THE AREA. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... SHORT TERM... MORNING FOG IN SHELTERED VALLEYS WILL LIFT EARLY THIS MORNING. THIS WILL ALLOW FOR SUNNY AND HUMID CONDITIONS...WITH THE DEVELOPMENT OF MORE SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. PATCHY FOG TO DEVELOP AGAIN TONIGHT WITH LOCAL IFR CONDITIONS...FOLLOWED BY MORE SHOWERS AND STORMS WEDNESDAY AFTERNOON. LONG TERM... THU - SAT...AREAS OF MVFR LIKELY IN SHOWERS AND THUNDERSTORMS. && .MARINE... SHORT TERM... SOUTHWEST FLOW CONTINUES THROUGH TUESDAY BUT SHOULD KEEP CONDITIONS BELOW ADVISORY LEVELS. LONG TERM... FRI - SAT...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
323 AM EDT TUE JUN 25 2013 .SYNOPSIS... STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE EXPECTED TODAY AS A FRONTAL BOUNDARY SAGS SOUTHWARD ACROSS THE AREA. UNSETTLED CONDITIONS WILL PERSIST THROUGH THE REMAINDER OF THE WEEK AND UPCOMING WEEKEND AS A BROAD AND SLOW MOVING LOW PRESSURE SYSTEM FROM THE GREAT LAKES MOVES EASTWARD.&& .NEAR TERM /THROUGH TONIGHT/... QUIET ACROSS THE FA FOR NOW AS WEAKENING BAND OF SHOWERS HAS EXITED OUR SERN AREAS WHILE ANOTHER CLUSTER OF SHOWERS AND TSTMS IS NOTED NW-N OF THE FA ALONG AND JUST W OF THE ST LAWRENCE... NR STATIONARY FRONTAL BNDRY N OF THE REGION XTNDG WNW-ESE FROM JAMES BAY ACROSS THE GASPE AND INTO THE GULF OF THE ST LAWRENCE. SEVERAL WEAK LOWS CONT TO SLIDE ESEWRD ALONG THIS BNDRY W/ THE STRONGEST OF THESE NR THE SERN TIP OF JAMES BAY ATTM. MODELS IN FAIRLY GOOD AGREEMENT AND ALLOW THIS SFC LOW NR JAMES BAY TO DROP SEWRD ALONG THIS FRONTAL BNDRY W/ THE FRONTAL BNDRY SAGGING SWRD ACROSS THE AREA FROM LATE TDY THRU TNGT. VRY WARM/HUMID AND UNSTABLE AIR IN PLACE ACROSS THE AREA S OF THIS BNDRY W/ SBCAPES FCST FROM 1000-2500 J/KG AND THIS WILL COMBINE W/ STRONG SFC AND UPPER DYNAMICS AS THIS FRONTAL BNDRY AND LOW PRES SAG SEWRD TOWARDS THE AREA LATER TDY TO PRODUCE THE THREAT OF STRONG TO PSBLY SEVERE TSTMS ACROSS THE AREA. CURRENTLY THE SPC HAS ALL BUT OUR DOWNEAST AREAS IN A SLIGHT RISK FOR SVR W/ DAMAGING WNDS THE PRIMARY THREAT. INITIAL ACTIVITY NW-N OF THE AREA IS FCST BY THE SHORTER TERM MODEL GUIDANCE LIKE THE HRRR AND RUC TO WEAKEN AND DISSIPATE AS IT REACHES OUR FAR NRN AREAS ERLY THIS AM BUT NOT SURE ABOUT THIS... IN ANY CASE...APPEARS STRONGER ACTIVITY WILL DVLP LATER THIS AM THRU THE AFTN HRS W/ HGHST POPS ACROSS THE N AND E CENTRAL AREAS IN TO THE EVE HRS W/ LOWEST POPS FAR SW. WILL CARRY MENTION OF SVR ALONG W/ ENHANCED WORDING FOR HVY RAIN/DAMAGING WNDS AND SMALL HAIL... FOR TNGT...GUIDANCE SUGGESTS THIS BNDRY WILL BE JUST S AND W OF THE FA BY ERLY WED W/ WEAK LOW PRES CNTRS OVR ERN NS...SRN MAINE AND SWRN QUEBEC. HIGH PRES W/ SOME DRIER AIR MAY TRY TO NUDE INTO FAR NERN AREAS BY LATE TNGT/ERLY WED... EXPECT ANOTHER WARM AND MUGGY DAY TDY W/ HIGH TEMPS LARGELY DEPENDENT ON CLD CVR. THINKING THERE WILL BE SOME SUN N AND NE W/ MORE PREVALENT SUNSHINE S AND W. WILL ADVERTISE HIGHS INTO THE LOWER 80S N W/ NR 90 PSBL SRN AREAS AWAY FROM THE COAST. ANOTHER WARM AND MUGGY NGT TNGT ACROSS RN AND WRN AREAS W/ SOME COOLER AND DRIER AIR LIKELY WORKING INTO NERN AREAS. PLENTY OF LOW LEVEL MOISTURE AND RATHER LGT WNDS SUGGESTS THE THREAT OF FOG TNGT ACROSS MUCH OF THE REGION... && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AN H5 UPPER LOW DEEPENS ACROSS THE GREAT LAKES REGION DURING THIS TIME FRAME. THIS WILL ALLOW AMPLE MOISTURE TO MOVE INTO NORTHERN NEW ENGLAND. EXPECT PERIODS OF SHOWERS BOTH DAYS. HIGHS WILL BE NEAR NORMAL ON WEDNESDAY AND MUCH BELOW NORMAL ON THURSDAY. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AN H5 UPPER LOW SLOWLY PROGRESSES INTO THE NORTHEAST U.S. LATE THIS WEEK AND THEN LIFTS INTO QUEBEC THIS WEEKEND. THIS ALLOWS THE DAMP WEATHER PATTERN TO PERSIST. THURSDAY NIGHT AND FRIDAY ARE FORECAST TO BE PARTICULARLY WET WITH PERIODS OF RAIN. TEMPERATURES WILL GRADUALLY WARM BACK TO SEASONAL LEVELS BY THE WEEKEND. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... NEAR TERM: PATCHY FOG ERLY THIS AM MAY RESULT IN SOME MVFR TO IFR CONDS UP UNTIL OR SHORTLY AFTER SUNRISE. MAINLY VFR CONDS ARE THEN EXPECTED OUTSIDE OF ANY SHOWERS/TSTMS W/ MVFR/IFR DURING THIS ACTIVITY. PATCHY TO AREAS OF FOG EXPECTED AGAIN TNGT ALONG W/ A THREAT OF SHOWERS MAINLY ACROSS THE SRN HALF OF THE FA. SHORT TERM: MVFR AND POSSIBLY IFR CIGS AND VSBYS ARE EXPECTED AT TAF SITES WITH SHOWERS...RAIN AND FOG. && .MARINE... NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY FOG TODAY...THEN IN AREAS OF FOG AND ANY SHOWERS/THUNDERSTORMS LATER TODAY AND TONIGHT. SHORT TERM: NO HEADLINES ARE FORECAST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...KHW SHORT TERM...OKULSKI LONG TERM...OKULSKI AVIATION...KHW/OKULSKI MARINE...KHW/OKULSKI
AREA FORECAST DISCUSSION
NWS GRAY ME
302 AM EDT TUE JUN 25 2013 .SYNOPSIS... HOT AND HUMID AIR CONTINUES TO BE PUSHED NORTH INTO NEW ENGLAND AS SOUTHWEST FLOW PERSISTS OVER THE AREA. THE THREAT FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE. BY THURSDAY AND FRIDAY THERE IS A CHANCE FOR A MORE CONSISTENT RAIN AS WEAK LOW PRESSURE DEVELOPS TO OUR WEST AND LIFTS NORTHEAST INTO QUEBEC. THIS WILL ALSO SHIFT THE WINDS MORE ONSHORE...WITH COOLER TEMPERATURES AT THE END OF THE END OF THE WEEK...ALTHOUGH HUMIDITY`S WILL NOT DROP OFF THAT MUCH. WE WILL SWITCH BACK TO A SOUTHERLY FLOW FOR THE WEEKEND...WITH WARMER AND CONTINUED HUMID CONDITIONS. && .NEAR TERM /THROUGH TODAY/... ..."SUPERMOON" TIDES REACHED 12 FEET IN PORTLAND EARLY THIS MORNING... LATEST HRRR RUN CONTINUES TO INDICATE CONVECTIVE INITIATION BEGINNING AROUND 18Z OVER FAR NORTHERN AND WESTERN PORTIONS OF THE FORECAST AREA. THIS IS IN RESPONSE TO SHORT WAVE RACING ACROSS SOUTHERN CANADA. WIND FIELDS WILL BE INCREASING (AND UNIDIRECTIONAL) WITH THIS FEATURE. WITH STEEP LOW LEVEL LAPSE RATES AND HIGH SURFACE DEW POINTS IN PLACE...CONVECTION TODAY WILL BE MORE ORGANIZED THAN YESTERDAY AS THE WIND MAX APPROACHES FROM THE NORTHWEST. DAMAGING STRAIGHT LINE WINDS ARE POSSIBLE IN ISOLATED STORMS...WITH LARGE HAIL POSSIBLE IN ANY OF THE STRONGER STORMS AS CAPE VALUES RAPIDLY CLIMB WITH GOOD SOLAR HEATING TODAY. HAVE ENHANCED WORDING IN THE GRIDS. PRECIPITABLE WATER VALUES REMAIN VERY HIGH. SOME OF THE SHOWERS AND STORMS MAY DROP VERY HEAVY RAIN IN A SHORT PERIOD OF TIME. STORMS WILL BE RELATIVELY FAST MOVING...BUT TRAINING OF SHOWERS WILL NEED TO BE MONITORED. AN AIR QUALITY ALERT WILL REMAIN IN EFFECT FOR TODAY...UNTIL 11 PM. && .SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/... WITH LOW LEVEL MOISTURE IN PLACE...AFTER AFTERNOON AND EVENING RAINS...PATCHY FOG WILL DEVELOP ONCE AGAIN ACROSS THE REGION TONIGHT. USED A BLEND OF MAV/MET MOS FOR OVERNIGHT MIN TEMPERATURES. MORE SHOWERS AND STORMS ARE POSSIBLE WEDNESDAY AFTERNOON AS A BACKDOOR COLD FRONT MOVES SOUTH ACROSS MAINE AND NEW HAMPSHIRE. SOME OF THESE STORMS MAY BE LOCALLY STRONG AS WELL. READINGS OVER SOUTHERN NEW HAMPSHIRE WILL SHOOT UP QUICKLY AHEAD OF THE SURFACE COLD FRONT...SO A HEAT WAVE (3 CONSECUTIVE DAYS AT OR ABOVE 90 DEGREES) IS STILL POSSIBLE OVER THIS REGION. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... THE MODELS ARE IN DECENT AGREEMENT WELL INTO NEXT WEEK ON EVOLVING LONGWAVE PATTERN. A SERIES OF SHORTWAVES RIDING OVER THE TOP OF THE WESTERN CONUS RIDGE WILL CARVE OUT A DEEP TROUGH ACROSS THE EAST BY THE UPCOMING WEEKEND. THE OVERALL THEME WILL BE WARM...HUMID...AND WET FOR THE FORECAST PERIOD. IN THE DAILIES...LOW PRESSURE WILL MOVE EAST FROM THE GREAT LAKES ON THURSDAY THEN SLOW DOWN AND LINGER ACROSS THE NORTHEAST THROUGH EARLY NEXT WEEK PRODUCING WARM, HUMID, AND WET WEATHER ACROSS THE AREA. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... SHORT TERM... MORNING FOG IN SHELTERED VALLEYS WILL LIFT EARLY THIS MORNING. THIS WILL ALLOW FOR SUNNY AND HUMID CONDITIONS...WITH THE DEVELOPMENT OF MORE SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. PATCHY FOG TO DEVELOP AGAIN TONIGHT WITH LOCAL IFR CONDITIONS...FOLLOWED BY MORE SHOWERS AND STORMS WEDNESDAY AFTERNOON. LONG TERM... THU - SAT...AREAS OF MVFR LIKELY IN SHOWERS AND THUNDERSTORMS. && .MARINE... SHORT TERM... SOUTHWEST FLOW CONTINUES THROUGH TUESDAY BUT SHOULD KEEP CONDITIONS BELOW ADVISORY LEVELS. LONG TERM... FRI - SAT...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
142 AM EDT TUE JUN 25 2013 .SYNOPSIS... ISSUED AT 403 PM EDT MON JUN 24 2013 HOT AND HUMID WEATHER WILL CONTINUE ACROSS THE REGION INTO MIDWEEK...AS HIGH PRESSURE DRIFTS OFF THE COAST OF THE SOUTHEAST STATES. THE HEAT AND HUMIDITY WILL BE ACCOMPANIED BY CHANCES OF SHOWERS AND THUNDERSTORMS...AS SEVERAL WAVES OF WEAK LOW PRESSURE TRACK ACROSS THE REGION. TEMPERATURES WILL GRADUALLY COOL DOWN LATE IN THE WEEK AND INTO NEXT WEEKEND...THOUGH CHANCES FOR A FEW SHOWERS WILL REMAIN THROUGH SATURDAY. && .UPDATE... ISSUED AT 125 AM EDT TUE JUN 25 2013 CLOUDS ARE SET TO ROLL IN OVER THE NEXT COUPLE OF HOURS...WHILE ISOLATED/SCATTERED SHOWERS AND STORMS ROLL ACROSS EASTERN UPPER IN RIGHT ENTRANCE REGION OF UPPER JET ROUNDING SHORTWAVE IN ONTARIO. THESE WILL CROSS CHIP/MACK COUNTIES THROUGH 0730Z. MEANWHILE...BACK ACROSS WISCONSIN...THERE APPEARS TO BE TWO SEPARATE SHORTWAVES BASED ON RUC ANALYSIS AND VWP`S. ONE RESULTING IN SLIGHTLY BACKING H8 WINDS BETWEEN LACROSSE AND MILWAUKEE. THIS HAS RESULTED IN SCATTERED SHOWER DEVELOPMENT AROUND GRB...WHICH WAS SLOWLY WORKING TOWARD THE GTV BAY REGION. NOT SURE HOW MUCH OF THAT CAN HOLD TOGETHER WITH GROWING MCS ACROSS SW WISCONSIN WHICH MAY DISRUPT IT`S INFLOW. LATEST HI RES HRRR...DOING A DECENT JOB AND WILL TWEAK POP GRIDS ACCORDINGLY...WITH SCATTERED ACTIVITY ROLLING INTO THE GTV BAY REGION OVER THE NEXT COUPLE OF HOURS. UPDATE ISSUED AT 945 PM EDT MON JUN 24 2013 MCS CONTINUES SLIDING EAST THRU THE NRN OHIO VALLEY THIS EVENING... WITH ADDITIONAL ISOLATED ACTIVITY FURTHER NORTH OVER WISCONSIN/UPPER MICHIGAN. MAIN QUESTION OVERNIGHT REMAINS POPS. BEST LOW LEVEL FORCING/FAVORABLE UPPER LEVEL SUPPORT REMAIN SOUTH/WEST OF THE AREA. AND STILL BELIEVE MUCH OF THE CONVECTION WILL REMAIN SOUTH OF THE CWA OVERNIGHT...LINING UP IN CLOSER PROXIMITY TO 850MB DWPT AXIS LAYING W-E ACROSS THE CENTRAL PORTIONS OF MICHIGAN AND WITHIN CORRIDOR OF SLIGHTLY STRONGER 850MB FLOW. CURRENT CONVECTION OVER UPPER MICHIGAN /LIKELY TIED TO 850MB THETA-E RIDGE NOSING INTO THAT AREA/ SHOULD DISSIPATE AS IT MOVES EAST OVER THE NEXT FEW HOURS. BUT GIVEN THIS ISOLATED ACTIVITY DEVELOPING DESPITE RATHER UNIMPRESSIVE FORCING...SIMPLY CAN/T RULE OUT AT LEAST LOW POPS OVER MUCH OF NRN LOWER MICHIGAN OVERNIGHT. WILL TREND HIGHEST POPS /30-40%/ SOUTH OF M-72...WITH LOWER CHANCES NORTH. STILL HAVE RELATIVELY LOW CONFIDENCE IN OVERALL CONVECTIVE EVOLUTION...AS AIRMASS REMAINS JUICY WITH SEVERAL UPSTREAM SHORTWAVE/VORT CENTERS. ADJUSTED LOW TEMPS UP A FEW DEG MOST LOCALES GIVEN CURRENT DWPTS AND PLENTY OF HIGH/MID LEVEL CLOUDINESS. UPDATE ISSUED AT 635 PM EDT MON JUN 24 2013 DIURNAL ISOLD SHWRS/TSTMS DISSIPATING WITH LOWER SUN ANGLE...AND WILL REMOVE FROM FORECAST OVER THE NEXT HOUR. NUMERICAL GUIDANCE CONTINUING TO STRUGGLE WITH CONVECTIVE TRENDS AND WILL BASE MUCH OF THE FORECAST TONIGHT ON OBSERVATIONAL TRENDS. MCS WORKING THRU SRN WISCONSIN/NRN ILLINOIS EARLY THIS EVENING WITHIN AXIS OF BEST LOW LEVEL BULK SHEAR/MUCAPE...MOVING MAINLY EAST WITH MEAN FLOW. MAIN QUESTION FOR NORTHERN MICHIGAN WILL BE IF ANY ADDITIONAL SHOWER/TSTM ACTIVITY CAN DEVELOP ON THE NORTHERN FRINGE OF CONVECTIVE COMPLEX...MORE CLOSELY ALIGNED WITH SYNOPTIC VORTICITY CENTER OVER SRN MINNESOTA. CAN STILL ENVISION SOME POSSIBILITY OF THIS HAPPENING...ALTHOUGH FEEL CURRENT POPS ARE LIKELY TOO FAR NORTH GIVEN CURRENT EXTRAPOLATION OF FEATURE. BECAUSE OF THIS...WILL TRIM POPS OVER THE NRN 1/2 OF THE AREA LATE TONIGHT...KEEPING SCATTERED SHWR/TSTM MENTION SOUTH OF M-32. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 403 PM EDT MON JUN 24 2013 EARLY AFTERNOON SURFACE ANALYSIS SHOWS A BROAD CIRCULATION AROUND A BERMUDA HIGH ENCOMPASSING THE OHIO VALLEY/GREAT LAKES REGION... PUMPING WARMTH AND HUMIDITY INTO MICHIGAN. REMNANTS OF A COLD FRONT WAS MOVING INTO WESTERN QUEBEC...WHILE A WEAK SURFACE LOW OVER EASTERN NEBRASKA HAS SEVERAL CONVECTIVELY INFLUENCED BOUNDARIES IN ITS VICINITY...AS A SLOW MOVING MCS AHEAD OF IT WORKS ITS WAY ACROSS THE MID MISSISSIPPI VALLEY. CLOSER TO HOME...BROKEN AREA OF AGITATED CU/TCU ACROSS MUCH OF NORTHERN LOWER...AND LYING ALONG LAKE BREEZE BOUNDARY ACROSS CHIPPEWA COUNTY. SCATTERED RADAR RETURNS HAVE POPPED EAST OF I-75 IN NORTHEAST LOWER...AND ALONG THE LAKE SUPERIOR BREEZE ACROSS CHIPPEWA COUNTY JUST SOUTH OF THE SOO WITHIN AN AREA OF 1000-1500J/KG MLCAPE. NUMERICAL GUIDANCE WILL CONTINUE TO BE PROBLEMATIC WITH THIS SCENARIO AS VARIOUS MODELS ARE HAVING DIFFICULT RESOLVING REALITY. MCS ACROSS IOWA IS AN ISSUE FOR TONIGHT...CLEARLY GETTING PUSHED ALONG BOTH BY A SYNOPTIC SCALE SHORT WAVE AND AN EMBEDDED MCV. SYNOPTIC VORTICITY CENTER EVIDENT IN VISIBLE IMAGERY SPINNING INTO SOUTHWEST MINNESOTA...WITH CLOUDS AND SOME SHOWERS/SPOTTY THUNDERSTORMS ROTATING AROUND TO THE NORTH OF THE MAIN MCS. THIS FEATURE TIMES INTO NORTHERN MICHIGAN LATE TONIGHT...SO BEYOND ANY ACTIVITY THAT POPS DURING THE LATE AFTERNOON HOURS...WILL BRING MORE CLOUDS BACK INTO THE REGION OVERNIGHT. MEANWHILE...MCS WILL CONTINUE TO PROPAGATE MOSTLY TO THE EAST BUT ASSOCIATED MCV APPEARS TO BE TRACKING A LITTLE NORTH OF EAST. THUS CAN ENVISION "COMMA HEAD" SHOWERS SLIPPING INTO NORTHERN LOWER MICHIGAN LATER TONIGHT PROVIDED THIS SYSTEM HOLDS TOGETHER. VORTICITY CENTER WILL LIKELY STILL BE CROSSING NORTHERN LOWER TUESDAY MORNING...SO CLOUDS AND SOME SHOWERS PROBABLY STILL AROUND ESPECIALLY SOUTH OF THE BRIDGE TO START THE DAY. IN THE WAKE OF THIS WAVE TO DRY THINGS OUT FOR THE AFTERNOON...ALLOWING TEMPERATURES TO WARM ONCE AGAIN INTO THE 80S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 403 PM EDT MON JUN 24 2013 SUMMERTIME WARMTH AND HUMIDITY TO CONTINUE INTO MIDWEEK WITH A BIT OF A COOL DOWN THEN EXPECTED NEXT WEEKEND INTO EARLY NEXT WEEK. THIS SHOULD MAKE EVERYONE HAPPY...SOME BEACH WEATHER TO START FOLLOWED BY BETTER SLEEPING CONDITIONS FOR NON-AIR CONDITIONING OWNING PEOPLE (LIKE ME). ANYWAYS...THE UPPER LEVEL RIDGE IN PLACE ACROSS THE REGION OVER THE LAST FEW DAYS GETS SLOWLY BEATEN DOWN THROUGH MIDWEEK BY THE PACIFIC NORTHWEST TROUGH. THIS WILL LEAVE BROAD UPPER TROUGHING ACROSS THE REGION LATER IN THE WEEK...WHICH SHOULD HOLD INTO EARLY NEXT WEEK AS WELL. THE MAIN FORECAST CONCERNS WILL CONTINUE TO REVOLVE AROUND POPS THROUGH THE PERIOD. TUESDAY NIGHT...NOT A WHOLE LOT TO HANG YOUR HAT ON...JUST A CHANCE FOR A COUPLE OF AIRMASS SHOWERS OR THUNDERSTORMS. REMAINING ON THE WARM AND HUMID SIDE WITH LOWS ONLY RANGING FROM THE MIDDLE 60S TO AROUND 70. WEDNESDAY...IT LOOKS LIKE THERE WILL BE A BETTER CHANCE FOR SHOWERS AND STORMS WITH THETA-E RIDGE BUILDING INTO THE REGION...AS WELL AS AN UPPER LEVEL TROUGH MOVING INTO THE REGION FROM THE WEST. THIS MAY WELL BE THE TRIGGER THAT HAS BEEN LACKING OVER THE LAST FEW DAYS TO BRING MORE NUMEROUS SHOWER AND THUNDERSTORM ACTIVITY (ESPECIALLY TO SOUTHERN SECTIONS OF THE FORECAST AREA). THE STORM PREDICTION CENTER (SPC) HAS NIXED THE SLIGHT RISK FOR SEVERE STORMS WHICH MAKES SENSE GIVEN THE ADVERTISED LIGHT WIND FIELDS ALOFT...THOUGH AN ISOLATED SEVERE STORM PROBABLY CAN NOT BE RULED OUT AT THIS EARLY JUNCTURE. CONTINUED VERY WARM AND HUMID WITH HIGHS RANGING FROM THE UPPER 70S NORTH TOT HE MIDDLE 80S SOUTH. LOWS AT NIGHT IN THE LOWER TO MIDDLE 60S. THURSDAY INTO FRIDAY...BROAD UPPER LEVEL TROUGHING IN COMBINATION WITH THE HEATING OF THE DAY AND POSSIBLE LAKE BREEZES WILL BRING ADDITIONAL CHANCES FOR SHOWERS. ADDED THUNDER CHANCES BACK INTO THE MIX FOR THURSDAY AS MODEL SOUNDINGS SHOW A DECENT AMOUNT OF CAPE AND LITTLE IN THE WAY OF INHIBITION. NOT AS WARM BUT STILL MUGGY WITH HIGHS THURSDAY RANGING FROM THE MIDDLE 70S TO LOWER 80S AND FRIDAY FROM THE LOWER 70S TO AROUND 80. LOWS THURSDAY NIGHT IN THE UPPER 50S TO LOWER 60S. SATURDAY THROUGH MONDAY...NOT A LOT OF CHANGE SATURDAY WITH LINGERING TROUGHING LEADING TO ADDITIONAL CHANCES FOR SHOWERS. SLOWLY RISING HEIGHTS FOR SUNDAY AND MONDAY (THOUGH LATEST ECMWF HOLDS ONTO THE TROUGH LONGER) WILL LEAD TO DECREASING CHANCES FOR SHOWERS. FORECAST HIGHS ALL THREE DAYS IN THE LOWER TO MIDDLE 70S. LOWS IN THE MORE COMFORTABLE 50S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 125 AM EDT TUE JUN 25 2013 A WEAK DISTURBANCE WILL MOVE ACROSS NORTHERN MICHIGAN THROUGH TUESDAY MORNING...RESULTING IN LOW CHANCES OF A SHOWER OR THUNDERSTORM AT ALL TERMINALS. THE CHANCE OF PCPN IS TOO LOW TO WARRANT A MENTION IN THE TAF. MAINLY MID/HIGH CLOUDS...WITH ISOLATED MVFR CIGS POSSIBLE NEAR PCPN. DIURNAL CU DEVELOPING TUESDAY AFTN...WITH BASES FROM 4-6K. WINDS GENERALLY LESS THAN 10KTS...WITH LAKE BREEZES POSSIBLE ON LAKE HURON. && .MARINE... ISSUED AT 403 PM EDT MON JUN 24 2013 WINDS WILL REMAIN LIGHT THROUGH THE MIDWEEK PERIOD...AND WILL BE INFLUENCED BY LAKE BREEZE CIRCULATIONS TUESDAY AFTERNOON. VISIBILITIES WILL BE LIMITED AT TIMES DUE TO FOG AND HAZE GIVEN HUMID AIR MASS IN PLACE ACROSS THE UPPER LAKES. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...SD SYNOPSIS...NS SHORT TERM...JB LONG TERM...AS AVIATION...JK MARINE...JB
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
409 AM CDT Tue Jun 25 2013 .SHORT TERM...(Today through Thursday) Issued at 405 AM CDT TUE JUN 25 2013 Challenge for today continues to be chances of precipitation through this afternoon as a nocturnal MCS propagates across central Kansas this morning. The 00Z sounding from KTOP showed ample dry layer such that severe winds were reported with very little convection or rain associated. Upstream of that a short wave trough and low level jet...along with around 8 deg K/KM mid level lapse rates supported upscale growth of an MCS that is producing severe winds as well. This will be the area to monitor as it moves eastward towards the CWA. At this time the storm appears to be splitting with a southern area taking on a more discrete...almost supercellular mode. Given the 0-6km shear in EAX CWA of around 40kts...will have to monitor this activity closely for potential severe threat. The HRRR favors maintaining the area although weakening somewhat after sunrise. The surface winds ahead of this area are decent enough to believe that the boundary layer is well mixed even if the convection itself is elevated. The 500 mb flow will still be at least slightly cyclonic and with the low level moisture and associated CAPE values around 2000 J/KG along with weak short wave ripples in the flow...therefore a chance of convection will last through the day today. As the thermal ridge builds into the area though...the chances for precipitation will decrease with the increased heating of the column late this evening through the remainder of the short term. All models show the upper ridge significantly amplifying over the western half of the US by tomorrow afternoon...so as the nose of the thermal ridge edges into the area...we will have heat indices in the 103F to 106F range on Wednesday. Will not issue a headline at this time because if there is another MCS overnight...some debris cloudiness could limit the temperatures/heat indices. As the ridge amplifies to the west the flow will eventually turn more northwesterly so we will begin to see slight relief by Thursday. Given this flow and cap in place...precipitation chances decrease as well during Thursday. The exception is a possible MCS that may from over eastern Iowa and clip the northeast corner. .LONG TERM...(Friday through Monday) Issued at 405 AM CDT TUE JUN 25 2013 Northwest flow will prevail through this period as a the ridge/trough pattern amplifies across the CONUS. A weak front should have moved through the area by Friday morning with scattered convection lingering into the day. But the bigger effect of the front will be to cool dewpoints down into the lower 60s or even the 50s. As we see a great influence from the eastern trough, temperatures aloft cool down and thickness values decrease substantially. So will also see a nice cool down in the surface temperatures by Saturday into the first half of next week, temperatures look to very close to normal, with highs in the lower to middle 80s. And when combined with the much more comfortable dewpoints, it looks like we`ll see couple days of pleasant summer weather. With regards to precipitation chances, northwest flow is notoriously tricky for timing and placing precipitation chances. At this time, there isn`t a great signal to say that any certain period of time has a greater chance of precipitation than any other period of time. So instead of carrying some mention of precipitation through the bulk of the extended range, have trimmed POPs out until there is a better signal. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1159 PM CDT MON JUN 24 2013 Convection over KS continues to sputter/fizzle as it moves east across the MO/KS state line. While short range models have not captured the rain area very well they have been spot on with respect to a lack of how much reaches the ground on the MO side. Cloud bases are quite high and this brings up the potential for gusty winds to 40kts should any convective cell dissipate as it passes near a terminal. Current indications are KSTJ has best chance of hearing thunder vs the two KC terminals and TAFs have been adjusted accordingly. Will amend forecasts should the KS convection cycle up but expect best rain chances overnight will be over northwest MO from KSTJ northward. Low confidence on convection on Tuesday due to a lack of a discernible boundary and forcing mechanism. Rain chances will be left to mesoscale processes/systems which are best left to later forecasts. Main theme will be the strong and gusty southerly winds. May see an occasional gust overnight but winds will become strongest by mid Tuesday morning and remain that way into the evening due to a strong pressure gradient and efficient momentum transfer of a stout low level jet. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...Adolphson LONG TERM...CDB AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1206 AM CDT Tue Jun 25 2013 .UPDATE... Issued at 1052 PM CDT MON JUN 24 2013 Neither the short range convection allowing models nor 00z NAM have much of a clue to the ongoing convection from southwest KS through west central MO. Activity appears to be aligning itself wsw-ene along a weak area of frontogenesis within the h8-h7 layer best depicted by the 02z RAP. The southerly h8 winds of 40-45kts is advecting ample moisture/instability across this boundary and with CIN values increasing since sunset this now supports elevated vs surface based convection. While the initial activity into our western counties tends to weaken/dissipate believe convection further upstream over KS will stand a better chance of surviving as it spreads eastward overnight and thus chance PoPs are warranted for the far west central and northwest portions of the CWA. && .SHORT TERM...(This Evening through Tuesday Night) Issued at 355 PM CDT MON JUN 24 2013 Main concern will be with potential for convection again tonight and then increasing heat conditions Tuesday. Latest HRRR model shows shortwave trough in synoptic flow to hold together as it moves into eastern Kansas. Dynamics are fairly weak as this is just a ripple in the nearly zonal flow over the region. However...there is some modest instability and potential for a decent LLJ late tonight....so another nocturnal MCS could move through...especially in northern zones where mid level lapse rates favor better instability. On Tuesday...there still is a chance in the afternoon in the northern zones for some convection to fire as yet another very weak short wave trough moves through. Also of concern is what might be left over in terms of outflow boundaries from any activity tonight. Therefore...will keep a chance in the northern zones for tomorrow. Meanwhile the thermal ridge begins to build to the west with 850mb temperatures into the middle and upper 20s deg C in western and central Kansas. As this thermal ridge moves towards the area...we will see heat indices begin to edge up to low 100s. Will not issue advisory for Tuesday but have mentioned it in the hazardous weather outlook. Tuesday night...yet another chance for some nocturnal MCS activity mainly in the northeastern zones as the thermal ridge axis moves over the western areas and should limit convection there. .LONG TERM...(Wednesday through Monday) Issued at 355 PM CDT MON JUN 24 2013 Beginning in the middle of the work week, the flattened zonal flow across the nation will begin to amplify as the prevailing westerlies begin to buckle across the U.S.A./Canadian border. The buckling in the flow will be lead by a weak shortwave Wednesday, with our region quickly finding itself in the the northwest flow as the ridge axis of the amplifying ridge pops up to to our west. However, as the weekend arrives the trough across the Great Lakes will gather some energy, expanding enough to possibly but much of our forecast area on the cool side of the still prevailing northwest flow. The pattern for the week will dictate hot and humid conditions through the middle of the work week, with Wednesday and Thursday being particularly muggy and troublesome. Dew points will be critical mid-week on determining the need for a heat advisory as heat indices will be ranging in the low 100s. Currently, forecast numbers are coming up just shy of criteria, though this currently looks due to the fact that afternoon dew points will likely mix out a little as the hot air advecting in aloft from the southwest will also be a bit dry. By Friday...temperatures are expected to back off a little from the hot and humid readings of the previous few days as the trough over the Great Lakes begins to dominate the eastern CONUS. Readings for Friday will still reach in the 90s, but the humidity wont be as bad; and for the weekend temperatures should range through the 80s. As for precipitation, only true potential for more than isolated storms looks to be focused on Thursday night into Friday morning as the edge of the Great Lakes trough begins pushing back to the southwest. Have kept PoPs in the chance category owing to the vagaries of forecast timing in a northwest flow. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1159 PM CDT MON JUN 24 2013 Convection over KS continues to sputter/fizzle as it moves east across the MO/KS state line. While short range models have not captured the rain area very well they have been spot on with respect to a lack of how much reaches the ground on the MO side. Cloud bases are quite high and this brings up the potential for gusty winds to 40kts should any convective cell dissipate as it passes near a terminal. Current indications are KSTJ has best chance of hearing thunder vs the two KC terminals and TAFs have been adjusted accordingly. Will amend forecasts should the KS convection cycle up but expect best rain chances overnight will be over northwest MO from KSTJ northward. Low confidence on convection on Tuesday due to a lack of a discernible boundary and forcing mechanism. Rain chances will be left to mesoscale processes/systems which are best left to later forecasts. Main theme will be the strong and gusty southerly winds. May see an occasional gust overnight but winds will become strongest by mid Tuesday morning and remain that way into the evening due to a strong pressure gradient and efficient momentum transfer of a stout low level jet. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...MJ SHORT TERM...Adolphson/73 LONG TERM...Cutter AVIATION...MJ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
342 AM EDT TUE JUN 25 2013 .SYNOPSIS... BERMUDA HIGH PRESSURE CENTERED WELL OFFSHORE WILL REMAIN IN PLACE INTO THE WEEKEND...WHILE WEAK UPPER IMPULSES TRACK JUST NORTH OF THE AREA. THIS WILL CONTINUE THE WARM AND HUMID CONDITIONS ACROSS THE AREA...WITH GOOD CHANCES FOR SHOWERS AND THUNDERSTORMS EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 AM TUESDAY...WILL KEEP A SLIGHT POP ALONG THE IMMEDIATE COAST DURING THE PRE-DAWN HOURS TO ACCOUNT FOR ANY ONSHORE MOVEMENT OF ATLANTIC SHRA/TSRA. MODELS INDICATE RATHER FLAT UPPER RIDGING EXTENDING NW ACROSS THE AREA FROM THE OFFSHORE WATERS OFF THE SE U.S. COAST. MODELS INDICATE WEAK MID-LEVEL TROFFINESS ACROSS THE SE STATES WHICH WILL LIKELY BE ENOUGH TO AID IN FIRING DIURNALLY DRIVEN CONVECTION. THE SEA BREEZE AND OUTFLOWS WILL BE THE OTHER AIDS TO KEEP CONVECTION FIRING THROUGH THE DAY AND INTO THE EVENING. LATEST HRRR DOES INDICATE CONVECTION TO FIRE AROUND SUNRISE BUT NOT BOUGHT ON ITS WIDESPREAD COVERAGE THAT EARLY. THINKING IS SOMEWHAT SIMILAR TO MONDAY CONCERNING POPS IN THE 30-50 PERCENT RANGE BY MID MORNING AND LASTING THROUGH MID-EVENING. NAMBUFR SOUNDINGS INDICATE 1.75 TO 2.00 PRECIPITABLE WATERS ACROSS THE FA ONCE AGAIN. THEREFORE...THE MAIN THREAT FROM TODAYS CONVECTION WILL BE THE HEAVY DOWNPOURS ACROSS GROUNDS THAT HAVE BECOME SOMEWHAT SATURATED FROM THE RECENT RAINS OF THE PAST FEW DAYS. WILL ONCE AGAIN HAVE A LOW DIURNAL RANGE BETWEEN MAX AND MIN TEMPS DUE TO CLOUDS AND PCPN THREAT. STAYED ON THE LOWER SIDE OF MODEL MOS GUIDANCE FOR TODAYS MAXES...AND THE HIGHER SIDE OF MODEL MOS FOR TONIGHTS LOWS. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...PERSISTENCE THE RULE FOR THE SHORT TERM AS SUMMERTIME PATTERN REMAINS IN PLACE WITH BERMUDA HIGH OFFSHORE AND FLAT RIDGING CONTINUING ALOFT. THIS CREATES A WARM...HUMID...AND ACTIVE PATTERN AS TEMPS RISE INTO THE LOW 90S AWAY FROM THE COAST...WITH LOWS FALLING ONLY INTO THE LOW 70S. HOWEVER...THERE WILL LIKELY BE CONSIDERABLE VARIABILITY EACH DAY AS CONVECTION LOOKS TO BE SCATTERED-TO-WIDESPREAD ACROSS THE AREA. IN ADDITION TO THE FLAT 5H RIDGING WHICH SLOWLY BEGINS TO BREAK DOWN...A WEAK VORT WILL CROSS OVERHEAD ON WEDNESDAY. TIMING THIS FEATURE IS STILL UNCERTAIN...AND THERE WILL BE A RACE BETWEEN SUBSIDENCE BEHIND THE VORT...AND AFTN INSTABILITY. ASSUMING THE VORT MOVES OFFSHORE EARLY...WILL CAP POP AT LOW-CHC...AND WEDNESDAY MAY BE THE DRIEST DAY OF THE WEEK. BY THURSDAY...MID LEVEL LAPSE RATES STEEPEN CONSIDERABLY AND MORE WIDESPREAD CONVECTION IS ANTICIPATED IN A CONTINUED HIGHLY UNSTABLE ENVIRONMENT. WHILE SEVERE CONVECTION LOOKS UNLIKELY...OR ISOLATED AT WORST...HEAVY RAIN AND FLOODING WILL CONTINUE TO BE A CONCERN IN A SATURATED COLUMN. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY...BIG CHANGES TO THE UPPER PATTERN DURING THE EXTENDED...BUT LITTLE SENSIBLE WEATHER DIFFERENCES TO BE EXPERIENCED ACROSS THE EASTERN CAROLINAS. 600DM RIDGE AT 5H EXPANDS ACROSS THE SW...CENTERED OVER THE 4-CORNERS REGION...FORCING A DEEPENING EASTERN CONUS TROUGH. LONGWAVE PATTERN BECOMES INCREASINGLY AMPLIFIED...WITH THE EASTERN TROUGH BOOKENDED BY LARGE RIDGES BOTH UPSTREAM AND DOWNSTREAM. THIS CAUSES THE LONGITUDINAL FLOW TO COME TO A SLOW/HALT...AND THE EASTERN TROUGH WILL PERSIST THROUGH THE EXTENDED. HOWEVER...WITH TROUGH AXIS REMAINING WELL WEST OF THE AREA...DEEP SW FLOW WILL ADVECT TREMENDOUS MOISTURE AGAIN INTO THE COLUMN...EVEN AS BERMUDA HIGH SLOWLY BREAKS DOWN. THIS SUPPORTS THE POTENTIAL FOR A VERY WET PERIOD RETURNING TO THE CAROLINAS...AND SAT-MON COULD BE EVEN WETTER THAN THE PAST FEW DAYS HAVE BEEN. WPC QPF GRAPHICS SUPPORT THIS...AS CHANNELED MOISTURE TAPS THE GULF OF MEXICO AND STREAMS RIGHT INTO THE AREA. FOR NOW WILL CONTINUE CHC POP THROUGH THE PERIOD WITH HIGHS RIGHT AROUND CLIMO AND LOWS JUST A BIT ABOVE. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...FOG/LOW STRATUS WILL LIKELY PLAGUE THE TERMINALS AGAIN EARLY THIS MORNING WITH THIS HUMID AIR MASS REMAINING ACROSS THE REGION. POCKETS OF MVFR VSBYS ARE POSSIBLE...WITH MAINLY IFR CIGS INLAND...BELOW 1K FEET...AND MVFR CIGS ALONG THE COAST. CANNOT RULE OUT TEMPO IFR FOR THE COASTAL SITES...BUT CONFIDENCE IS HIGHER FOR IFR CIGS AT KLBT/KFLO. SHRA/TSRA LIKELY WILL DEVELOP NEAR THE COAST IN THE MORNING BEFORE SHRA/TSRA SHIFTS INLAND DURING THE AFTN...WITH THE SEA BREEZE AND OUTFLOW BOUNDARIES BEING THE PRIMARY LIFTING MECHANISMS. TEMPO MVFR/IFR WILL OCCUR IN HEAVY DOWNPOURS...BUT PREVAILING VFR IS EXPECTED DURING THE DAY. RIDGING ACROSS THE AREA FROM THE WESTERN ATLANTIC HIGH WILL PRODUCE S/SW WINDS AROUND 5 KTS INLAND TERMINALS...AROUND 10 KT...EXCEPT UP TO 15 KT ACROSS THE COASTAL TERMS DURING THE HEIGHT OF THE SEA BREEZE CIRCULATION LATER TODAY. EXTENDED OUTLOOK...ISO/SCT AFTERNOON SHOWERS AND T-STORMS THROUGH SATURDAY WITH LOCALIZED PERIODS OF MVFR/IFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 AM TUESDAY...RIDGING SFC AND ALOFT WILL CONTINUE ITS HOLD ACROSS THE AREA WATERS THIS NEAR TERM PERIOD. THE SFC RIDGE AXIS EXTENDING FROM THE WESTERN ATLANTIC HIGH IS PROGGED TO DROP SOUTH OF THE ILM WATERS PRIOR TO EXTENDING INLAND. THIS WILL RESULT IN A SW WIND DIRECTION BECOMING DOMINANT THROUGHOUT THE AREA WATERS DURING THIS TIME PERIOD. IN ADDITION...THE PIEDMONT TROF ACROSS THE CENTRAL CAROLINAS WILL BEGIN TO MATERIALIZE BY LATE IN THE PERIOD. THE SFC PG WILL REMAIN SOMEWHAT ON THE LOOSE SIDE THIS PERIOD...AND SHOULD SUPPORT 10 TO POSSIBLY 15 KT WIND SPEEDS. THE HIER SPEEDS LIKELY TO BE AIDED BY THE SEA BREEZE CIRCULATION NEAR SHORE. SIGNIFICANT SEAS WILL RUN AROUND 3 FEET...WITH FLUCTUATIONS BETWEEN 2 AND 4 FT. THE ESE-SE GROUND SWELL AT 7 TO 9 SECOND PERIODS WILL DOMINATE THE SIGNIFICANT SEAS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...BERMUDA HIGH PRESSURE REMAINS ANCHORED OFFSHORE THROUGH THE PERIOD CONTINUING SW WINDS ACROSS THE WATERS. WHILE THE PATTERN IS FAIRLY STATIC...GRADIENT WILL SLOWLY TIGHTEN...ESPECIALLY THURSDAY...THANKS TO A STRENGTHENING PIEDMONT TROUGH AND SLOWLY APPROACHING COLD FRONT. THIS CAUSES SW WINDS TO INCREASE FROM 10-15 KTS ON WEDNESDAY...TO 15-20 KTS DURING THURSDAY. WHILE A RESIDUAL 8 SEC SE SWELL WILL PERSIST IN THE WAVE SPECTRUM...SEAS WILL BECOME INCREASINGLY WIND-WAVE DOMINATED THANKS TO THE INCREASING WINDS. SIGNIFICANT WAVE AMPLITUDES WILL GROW FROM 2-4 FT WEDNESDAY...TO 3-5 FT THURSDAY...AND A FEW 6 FTERS MAY DEVELOP BY THE END OF THE PERIOD...AND WILL NEED TO MONITOR THIS FOR A POTENTIAL SCA BEGINNING LATE THURSDAY NIGHT. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 300 AM TUESDAY...HIGH PRESSURE ANCHORED WELL OFFSHORE AND COLD FRONT STALLED WELL INLAND FROM THE COAST...WILL KEEP A CONTINUOUSLY TIGHTENING PRESSURE GRADIENT OVER THE WATERS. THIS HELPS SW WINDS RISE TO AROUND 20 KTS BOTH DAYS...AND SEAS BUILD IN RESPONSE TO THESE GUSTY WINDS. WAVE HEIGHTS WILL BE 4-7 FT THROUGH THE PERIOD...AND AN EXTENDED SMALL CRAFT ADVISORY IS POSSIBLE FOR ALL LOCAL WATERS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...JDW AVIATION...DCH/BJR MARINE...DCH/JDW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
102 AM CDT TUE JUN 25 2013 .UPDATE... ISSUED AT 101 AM CDT TUE JUN 25 2013 DID INCREASE POPS ACROSS THE FAR NORTHWEST TO LIKELY NEAR 12 UTC GIVEN THE LATEST RADAR TRENDS OF THE ONGOING CONVECTION ACROSS EASTERN MONTANA. DO NOT ANTICIPATE THESE STORMS TO BE SEVERE GIVEN MARGINAL EFFECTIVE DEEP LAYER SHEAR OF 20-25 KTS AND A EXPECTED DECREASE IN HAIL AND DOWNDRAFT CAPE VALUES THROUGH THE NIGHT. OTHERWISE...THE REMAINDER OF THE FORECAST FOR TONIGHT IS ON TRACK. IN REGARDS TO TUESDAY...CONSIDERING THE NEED FOR A FLASH FLOOD WATCH FOR NORTHERN AND CENTRAL NORTH DAKOTA. VERY SLOW STORM MOTIONS ARE ANTICIPATED WITH PWAT VALUES CLIMBING TO 1.75 INCHES AND K INDEX VALUES OF 40 TO 45 C. UPDATE ISSUED AT 1000 PM CDT MON JUN 24 2013 CURRENTLY...AN LONE CELL WAS LOCATED OVER NORTHERN MCLEAN COUNTY IN CENTRAL NORTH DAKOTA. LATEST 01Z HRRR CONTINUES TO TRY AND DEVELOP CONVECTION ACROSS THE WEST AND NORTH CENTRAL OVERNIGHT SO CANT COMPLETELY RULE OUT A THUNDERSTORM. THEREFORE WILL CONTINUE TO CARRY A SLIGHT CHANCE OF STORMS TONIGHT. AFTER MIDNIGHT...THERE APPEARS TO BE A BETTER CHANCE OF CONVECTION OVER NORTHWEST NORTH DAKOTA AS CURRENT CONVECTION IN CENTRAL MONTANA TRANSLATES EAST. BULK SHEAR OVER THIS AREA SHOULD INCREASE OVERNIGHT AS A SHORTWAVE OVER THE NORTHWEST U.S. PUSHES INTO THE NORTHERN ROCKIES. THUS HAVE KEPT SOME HIGHER CHANCE POPS OVER THE NORTHWEST INTO THE FAR NORTH CENTRAL TOWARD MORNING. FOG CHANCES APPEAR MINIMAL WITH A STEADY SOUTHEAST FLOW...BUT DO THINK THERE IS A CHANCE OF INCREASING LOW STRATUS TUESDAY MORNING. NO CHANGES TO OVERNIGHT LOWS AS A WARM AND MUGGY NIGHT LOOKS TO BE IN STORE WITH LOWS IN THE LOW TO MID 60S. UPDATE ISSUED AT 709 PM CDT MON JUN 24 2013 UPDATE THIS EVENING DEALS MAINLY WITH EVENING CONVECTION. STILL QUITE UNSTABLE THIS EVENING BUT MODELS SUGGEST WITHOUT SUFFICIENTLY STRONG SHORTWAVE TO INITIATE CONVECTION...THE CAP WILL HOLD. THIS IS EVIDENT WITH THE CONVECTION THAT DEVELOPED JUST NORTH OF BISMARCK LATE THIS AFTERNOON...WHICH CONTINUES TO STRUGGLE TO SURVIVE. HAVE LOWERED POPS TO SLIGHT CHANCE ACROSS MOST OF THE AREA THIS EVENING. KEPT SOME CHANCE POPS IN THE FAR SOUTH IN CASE CONVECTION OVER WESTERN SOUTH DAKOTA MAKES IT UP TO THE BORDER. IF WE COULD GET A CELL TO BREAK THE CAP WE COULD STILL SEE A MARGINALLY SEVERE THUNDERSTORM BUT WITH A WEAK SHEAR PROFILE THIS EVENING...ORGANIZED CONVECTION LOOKS LESS LIKELY THAN IT DID EARLIER IN THE DAY. MODELS ALSO SUGGEST A CONTINUED INFLUX OF LOW LEVEL MOISTURE OVERNIGHT AND DEVELOP LOW STRATUS AFTER MIDNIGHT. THEREFORE BUMPED UP CLOUD COVER LATE TONIGHT...BUT WITH A STEADY SOUTHEAST GRADIENT...THINK THE POTENTIAL FOR FOG DEVELOPMENT IS LIMITED. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 300 PM CDT MON JUN 24 2013 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE STRONG TO SEVERE STORMS NOW THROUGH TUESDAY. LATEST HRRR...RAP...AND BOTH THE 12Z GFS/NAM ARE INDICATING CONVECTION FIRING OFF ANYWHERE FROM NOW THROUGH 21Z OVER THE SOUTHWEST AND SOUTH CENTRAL...SO WILL MAINTAIN HIGHER POPS FOR THESE AREAS. LOTS OF UNCERTAINTY YET WITH THE MID LEVEL CAPPING INVERSION STILL IN PLACE. WIND DISCONTINUITY/WEAK FRONTAL BOUNDARY IS APPARENT WHEN LOOKING AT WIND AND DEWPOINT FIELDS. MOISTURE IS CONVERGING ACROSS THE SOUTHWEST/SOUTH CENTRAL SOUTH OF THIS BOUNDARY WHERE SOUTHEAST WINDS ARE STRONGER. DEWPOINT TEMPS LOWER FARTHER NORTH WITH WEAKER SFC WINDS TO THE NORTH OF THIS BOUNDARY. INCOMING S/WV IMPULSE OVER NORTHWEST SOUTH DAKOTA NEARING SOUTHWEST NORTH DAKOTA WILL BE THE TRIGGER FOR POSSIBLE CONVECTION ONCE AFTERNOON HEATING CONTINUES TO WEAKEN THE CAP. STORMS WILL CONTINUE INTO THE EVENING BEFORE EVENTUALLY WINDING DOWN LATER THIS EVENING AND OVERNIGHT. STRONGER SHORT WAVE MOVES INTO THE DAKOTAS TUESDAY ALONG WITH A COLD FRONTAL PASSAGE TUESDAY AFTERNOON INTO TUESDAY EVENING. STRONG TO SEVERE CONVECTION WILL BE VERY POSSIBLE MANY AREAS...SO WILL MAINTAIN HIGH CHANCES FOR THUNDERSTORMS AND MENTION SEVERE. WILL NEED TO MONITOR LATEST GUIDANCE THIS EVENING AND TONIGHT IN CASE A FLASH FLOOD WATCH BECOMES NECESSARY. RIGHT NOW IT APPEARS STORMS WILL BE FAIRLY PROGRESSIVE. MODELS ARE ALSO PUTTING THE HEAVIEST QPF NORTHWEST AND NORTH CENTRAL...AWAY FROM THE AREAS WHICH RECEIVED THE HEAVIEST RAINFALL THE PAST SEVERAL DAYS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 300 PM CDT MON JUN 24 2013 SHORTWAVE TROUGH AND SURFACE COLD FRONT WILL BE EXITING THE JAMES RIVER VALLEY BY AROUND 06Z WEDNESDAY. EXPECT THREAT OF SEVERE WEATHER TO CONTINUE THROUGH TUESDAY EVENING THEN WANE WEST TO EAST AND END QUICKLY SHORTLY AFTER MIDNIGHT. BEHIND THE DEPARTING WAVE WEDNESDAY A WESTERLY FLOW ENSUES WITH ADDITIONAL SHORTWAVE ENERGY RIDING ACROSS SOUTHERN CANADA. TRENDS WITH THE 12Z RUNS PUSH PREVIOUS CHANCES OF PRECIPITATION FROM NORTH CENTRAL NORTH DAKOTA NOW INTO CANADA RESULTING IN AN OVERALL DRY SCENARIO. HAVE ADJUSTED THE GRIDS TO REFLECT THIS. THEREAFTER...MOSTLY A DRY WEATHER PATTERN AS A FOUR CORNERS HIGH PRESSURE AMPLIFIES NORTH WITH THE RIDGE AXIS EXTENDING WELL INTO SOUTHERN CANADA. HOWEVER A COMPENSATORY NORTHWEST FLOW DOWNSTREAM INTO NORTH DAKOTA WILL DOMINATE THROUGH THE WEEKEND WITH STILL SOME UNCERTAINTY ON HOW MANY SHORTWAVES WILL TOP THE RIDGE AND SLIDE THROUGH NORTHERN AND CENTRAL NORTH DAKOTA. THIS COULD PRODUCE SOME CONVECTION OVER THE WEEKEND...AND ESPECIALLY AT NIGHT WHICH IS A COMMON THEME WITH RIDGE RUNNERS TOPPING THE RIDGE THIS TIME OF YEAR. FAVORED AREAS WOULD BE THE TURTLE MOUNTAINS AND EAST CENTRAL NORTH DAKOTA. MODELS SHOWS A COUPLE OF WAVES EMBEDDED IN THE NORTHWEST FLOW...WITH THE ECMWF SHOWING THESE WAVES FURTHER EAST THAN THE GFS...SO TOO UNCLEAR ON EXACT DETAILS AT THIS TIME. WILL USE THE ALLBLEND WHICH CARRIES A SLIGHT MENTION OVER THE WEEKEND AND WILL NOT MAKE ANY CHANGES AT THIS TIME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 101 AM CDT TUE JUN 25 2013 FOR TONIGHT...MVFR STRATUS AND FOG ARE POSSIBLE AT ALL TAF SITES...SUPPORTED BY THE LATEST LAMP GUIDANCE. THUNDERSTORMS ARE POSSIBLE AT KISN BY 12 UTC AS STORMS APPROACH FROM MONTANA. THUNDERSTORMS ARE EXPECTED FOR MUCH OF NORTHERN AND CENTRAL NORTH DAKOTA TUESDAY AFTERNOON AND EVENING. SOME STORMS MAY BE SEVERE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...NH LONG TERM...KS AVIATION...AYD
AREA FORECAST DISCUSSION
NWS SPOKANE WA
236 AM PDT Tue Jun 25 2013 .SYNOPSIS... A wet pattern will continue across the Inland Northwest through mid week...with frequent showers and the potential for thunderstorms. The weather the second half of the week will be dramatically different as a warming and drying trend quickly develops by late week. Summer-like temperatures will be likely as we move towards the end of the week. && .DISCUSSION... Today and tonight...Little if any change to the longwave pattern consisting of large longwave trof offshore up against inland ridging which continues to funnel through negatively tilted disturbances tied into moderate and effective sources of moisture. The end result is another fairly wet forecast for today that shows some improvement after 11 pm tonight but still not yet enough to dry it out totally as per the latest GFS with a number of this morning`s HRRR model runs support this solution. Otherwise with such abundant moisture lingering from past and present rainfall some low clouds and fog may get mentioned at times in the mix. Minor change was removal of thunderstorm mention near the cascades as lapse rates don`t appear to be steep enough to support it there but have left minor mention for afternoon and evening further east closer to Spokane and vicinity and the North Idaho Panhandle. /Pelatti Wed through Sat morning: Following what should be our last day of meaningful chances of pcpn on Wed into Wed Nt will be a rapid warming and drying trend beginning Thurs. This pcpn chance Wed should not be too widespread, but certainly heaviest during the afternoon and evening as the region remains under a long-fetch moisture plume drifting north. This pcpn threat will last into Thurs morning. Though not currently in the fcst, there could be an isolated threat of thunder Wed afternoon across NE Wa as well as near the Camas Prairie and Nrn Blue Mtns of Wa. One note of interest concerning pcpn chances Fri Nt: The GFS advects of plume of elevated instability above about 700mb north through Oregon and into SE Wa Fri Nt. The RH in this layer a rather dry, and the GFs is the only model guidance that produces nocturnal pcpn (very light and spotty). We did not put any of this pcpn in the fcst, but it`s something to watch. 500mb ht rises close of 150-200m, accompanying 850mb temp rises around 10c, will push hi temps nearly 10F above normal by Fri. bz Saturday through Tuesday...An upper level ridge will amplify dramatically over the Inland Northwest through early next week, with the result being the hottest temperatures we`ve seen so far this early summer season (it`s still very early). All the gnashing of teeth regarding the recent rainfall and cool temperatures will stop as temperatures will warm well into the 80s and 90s, with isolated locations approaching the century mark. The extended models produce high temperatures that are 15+ above normal. Had it not been for the recent soaking rainfalls the hot temperatures may not be as hard to realize. But since many areas have received their June`s average total rainfall over the last week, afternoon temperatures should remain below the hottest of the guidance numbers. At least through the weekend. If the ridge continues to amplify next week, enough drying at the surface would allow for even higher temperatures. ty && .AVIATION... 06Z TAFS: An exiting weather system will leave some remaining moisture and residual showers overnight. As a result, we will continue to see the possibility of MVFR cigs and vis at times overnight with the threat of valley fog especially north of Interstate 90 through 17Z Tuesday. Another moisture surge moves into the Cascades with a round of showers progressing from southwest to northeast through the day on Tuesday. There will also be a possibility of isolated thunderstorms and localized MVFR ceilings late Tuesday morning into Tuesday afternoon. TC && .PRELIMINARY POINT TEMPS/POPS... Spokane 65 52 73 54 79 57 / 90 50 30 10 0 0 Coeur d`Alene 65 52 72 53 79 54 / 90 50 30 10 0 0 Pullman 65 53 73 54 81 53 / 80 50 40 10 0 0 Lewiston 73 57 81 58 89 60 / 80 60 40 20 0 0 Colville 69 52 74 53 82 53 / 90 60 40 20 0 0 Sandpoint 66 51 71 52 77 50 / 90 60 40 20 0 0 Kellogg 63 50 69 52 77 56 / 90 60 30 20 0 0 Moses Lake 70 57 78 58 86 59 / 70 20 10 10 0 0 Wenatchee 70 55 77 60 84 63 / 80 20 20 10 0 0 Omak 70 53 76 54 82 57 / 80 30 20 10 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1222 AM CDT TUE JUN 25 2013 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 304 PM CDT MON JUN 24 2013 AT 3 PM...A SQUALL LINE WAS MOVING EAST THROUGH EAST-CENTRAL AND SOUTHEAST IOWA. THIS LINE HAS WIPED OUT MUCH OF THE INSTABILITY THAT MANY OF 24.00Z AND 24.06Z MODELS WERE FORECASTING TO MOVE INTO NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST AND CENTRAL WISCONSIN TONIGHT. EVEN SOME OF THE 24.12Z DETERMINISTIC MODELS WERE NOT HANDLING THIS LINE WELL...SO THEY ARE TOO HIGH ON THEIR CAPES ACROSS IOWA. IN ADDITION...THIS LINE ALSO DISRUPTED THE 925 MB AND 850 MB MOISTURE TRANSPORT INTO THE REGION. AS A RESULT...THE HEAVY RAIN THREAT FOR THIS EVENING LOOKS MUCH LESS THAN WHAT IT WAS LOOKING LIKE EARLIER THIS MORNING. FOR OVERNIGHT...THERE IS A LOT OF UNCERTAINTY ON HOW THIS PERIOD IS GOING TO MATERIALIZE. THE 24.12Z NAM WHICH HAD A SLIGHTLY BETTER HANDLE ON THE SQUALL LINE PUSHED AN OUTFLOW BOUNDARY SOUTH TO THE MISSOURI AND IOWA BORDER...THUS ITS BEST MOISTURE TRANSPORT IS FOCUSED MUCH FURTHER SOUTH. THE 925 MB MOISTURE TRANSPORT HAS SHIFTED TOWARD SOUTHERN IOWA. IF THIS VERIFIES... MUCH OF THE PRECIPITATION WOULD REMAIN SOUTH OF THE AREA FOR THIS TIME PERIOD. EVEN THE LATEST RAP IS LEANING TOWARD THIS SCENARIO TOO. MEANWHILE BOTH THE ECMWF AND GEM MODELS SUGGEST THAT AS THE SHORT WAVE IN THE SOUTHERN PLAINS MOVES NORTHEAST INTO THE SOUTHERN PLAINS...THE 850 MB MOISTURE TRANSPORT SHIFTS BACK NORTHWARD TOWARD THE AREA TOWARD SUNRISE. IF THIS SCENARIO VERIFIES...THERE COULD BE A POTENTIAL FOR THE REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS LATE TONIGHT. WITH ITS PRECIPTABLE WATER VALUE CLOSE TO 2.00 INCHES AND WARM CLOUD LAYER DEPTHS UP TO 4.5 KM...THERE WOULD BE THE POTENTIAL FOR HEAVY RAIN. WITH SO MANY DIVERSE MODEL SOLUTIONS...OPTED TO LOWER THE PRECIPITATION CHANCES SOME AND ALSO SHIFTED THE HIGHER CHANCES TO LATER IN THE NIGHT. HOPEFULLY...THE 24.00Z MODELS WILL BE BETTER AT RESOLVING THE STABLE LAYER THAT WAS LEFT IN THE WAKE OF THE SQUALL LINE. ON TUESDAY...EXPECT THE 925 MB AND 850 MB MOISTURE TRANSPORT TO INCREASE ACROSS IOWA. HOWEVER THERE IS SOME UNCERTAINTY HOW FAR NORTH THIS OCCUR. THE 24.18Z NAM AND 24.12Z GFS WOULD SUGGEST THAT THE HEAVIEST RAIN WOULD FALL ACROSS CENTRAL IOWA. MEANWHILE THE 24.12Z ECMWF AND GEM WOULD SUGGEST THAT THE HEAVIEST RAIN WOULD FALL SOUTH OF INTERSTATE 90. WITH THE INITIAL CONDITIONS SO MUDDLED...CONFIDENCE IS NOT THAT HIGH. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 304 PM CDT MON JUN 24 2013 ON TUESDAY NIGHT...MUCH OF THIS TIME PERIOD REMAINS UNCLEAR DUE TO UNCERTAINTIES ON WHERE THE BOUNDARIES WILL END UP FROM TONIGHT AND WHERE THUNDERSTORMS DEVELOP ON TUESDAY. THE GEM AND ECMWF HAVE THEIR MESOSCALE CONVECTIVE COMPLEXES MOVING ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR. MEANWHILE THE GFS AND NAM SUGGEST THAT THE MESOSCALE CONVECTIVE COMPLEX WILL DEVELOP ACROSS IOWA...AND THEN MOVES IT NORTHEAST WITH THE SHORT WAVE INTO THE FORECAST AREA. WITH WARM CLOUD LAYER DEPTHS OVER 4 KM AND PRECIPITABLE WATER VALUES AROUND 2 INCHES. THERE WILL BE THE POTENTIAL FOR SOME FLASH FLOODING. ON WEDNESDAY AND WEDNESDAY EVENING...ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA AS THE LOW PRESSURE AREA MOVES EAST ACROSS THE AREA. PRECIPITABLE WATER VALUES SLOWLY DROP TO AROUND 1.60 INCHES AND THE WARM CLOUD LAYER DEPTHS FALL INTO THE 3 TO 3.5 KM RANGE. WHILE THERE WILL BE THE POTENTIAL FOR SOME HEAVY RAIN...THE AMOUNTS LOOK TO BE MUCH LESS THAN WHAT THEY ARE FROM TONIGHT INTO TUESDAY NIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1222 AM CDT TUE JUN 25 2013 COMPLEX OF STORMS HAS DEVELOPED OVER THE AREA THIS EVENING AHEAD OF A SHORT WAVE TROUGH AND WITH THE LOW LEVEL JET AIMED RIGHT AT THE AREA. ACTIVITY CONTINUES TO BE PROGRESSIVE BUT DOES CONTINUE TO REDEVELOP BACK ACROSS SOUTH CENTRAL MINNESOTA. THE 25.03Z HRRR SEEMS TO HAVE A GOOD HANDLE ON THE SITUATION AND SHOWS THE CONVECTION CONTINUING THROUGH ABOUT 10Z OR SO WHEN THE SHORT WAVE TROUGH STARTS TO MOVE OFF TO THE EAST AND THE LOW LEVEL MOISTURE TRANSPORT STARTS TO REFOCUS BACK ON THE ON GOING ACTIVITY ACROSS NEBRASKA AND KANSAS. PLAN TO CARRY A TEMPO GROUP FOR THUNDER AT BOTH SITES THROUGH 10Z AND THEN SHOW VCTS INTO THE MIDDLE OF TUESDAY MORNING JUST IN CASE THE ACTIVITY IS SLOWER TO MOVE OUT. SHOULD SEE A BREAK FOR LATE MORNING INTO THE AFTERNOON BEFORE THE NEXT ROUND DEVELOPS. SEVERAL OF THE MODELS ARE SHOWING THE MAIN WARM FRONT LIFTING NORTH TOWARD THE AREA. THE FRONT HAS BEEN MOVING AND IS NOW INTO SOUTHERN IOWA SO NOT OUT OF THE QUESTION FOR IT TO BE NEAR THE AREA BY TUESDAY AFTERNOON. THE LOW LEVEL MOISTURE TRANSPORT RAPIDLY INCREASES DURING THE AFTERNOON INTO THE FRONT AHEAD OF THE MAIN UPPER LEVEL TROUGH WITH CONVECTION EXPECTED TO RAPIDLY DEVELOP IN THE AFTERNOON. HAVE INCLUDED VCTS FOR BOTH SITES TO SHOW THIS POSSIBILITY AND LATER FORECASTS WILL HAVE TO DETAIL THIS BETTER WHEN THE DETAILS BECOME CLEARER AS TO WHERE THESE STORMS WILL DEVELOP. && .HYDROLOGY... ISSUED AT 304 PM CDT MON JUN 24 2013 WITH A WIDE VARIETY OF SOLUTIONS IN THE 24.12Z AND 24.18Z MODELS...CONFIDENCE HAS LOWERED ON THE THREAT FOR FLASH FLOODING TONIGHT. HOWEVER WITH MANY RIVERS REMAINING EITHER HIGH OR ARE FLOODING ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. CONFIDENCE WAS NOT HIGH ENOUGH TO CANCEL THE FLASH FLOOD WATCH. LOOKING AHEAD TO TUESDAY AND TUESDAY NIGHT...SOME MODELS SUGGEST THAT HEAVY RAIN COULD FALL SOUTH OF INTERSTATE 94. MEANWHILE OTHER MODELS HINT THAT THE HEAVIEST PRECIPITATION WILL REMAIN SOUTH OF THE FORECAST AREA. WITH SUCH DIVERSE SPREADS IN THE MODELS...OPTED NOT TO EXTEND THE FLASH FLOOD WATCH INTO TUESDAY NIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH UNTIL 10 AM CDT TUESDAY FOR WIZ032>034-041>044- 053>055-061. MN...FLASH FLOOD WATCH UNTIL 10 AM CDT TUESDAY FOR MNZ079-086>088- 094>096. IA...FLASH FLOOD WATCH UNTIL 10 AM CDT TUESDAY FOR IAZ008>011-018-019- 029-030. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...04 HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1118 AM EDT TUE JUN 25 2013 .SYNOPSIS... BERMUDA RIDGE KEEPS THE REGION LOCKED IN A HOT AND HUMID AIRMASS THROUGH AT LEAST THE END OF THE WORK WEEK. A STRONG COLD FRONT WILL NEAR FROM THE NORTHWEST ON THURSDAY BUT BEGIN TO SLOW UPON ITS ARRIVAL. THE FRONT SHOULD LIMP THROUGH BY FRIDAY BUT THEN STALL TO OUR IMMEDIATE EAST THROUGH EARLY NEXT WEEK KEEPING A PROLONGED PERIOD OF UNSETTLED WEATHER. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 12Z UA ANALYSIS SHOWS A MUCH LESS DYNAMIC SET-UP IN OUR CWA FROM YDA AS UPSTREAM 700 AND 500 MB TEMPS ARE 2 TO 4C WARMER AND GONE IS THE STGR DPVA AND 50-60KT JET STREAK FROM YDA. 12Z WRF-NMMB KEEPS DECENT FORECAST BULK SHEAR NORTH OF OUR CWA AND FCST MID LEVEL LAPSE RATES ARE ABOUT 1C/KM LESS THAN YESTERDAY. OVERALL THINK THAT THE LATEST HR3 AND RAP HAVE A BETTER HANDLE ON THE EVOLUTION FOR THIS AFTERNOON INTO THIS EVENING THAN THE MORE CHARGED 00Z HI RES NMM AND ARW DO. NOTWITHSTANDING ABOVE AND I HAVE BEEN WRONG BEFORE AND WILL BE WRONG AGAIN (MAYBE BY 4 PM OR EVEN EARLIER), WILL HAVE TO SEE HOW CONVECTION FAR NORTH EVOLVES FROM NWRN PA AS ITS THE CLOSEST TO THE BEST FCST BULK SHEAR. WE ADJUSTED POP ORIENTATION HIGHEST NNW AND LOWEST SSE IN OUR CWA. 12Z UA ANLYS SUGGESTING NO FURTHER ADJUSTMENT TO MAX TEMPS NEEDED. SURPRISED HOW DEW POINTS ONCE AGAIN STRUGGLING TO DROP IN SPITE OF DRIER AIR AGAIN JUST ABOVE THE BOUNDARY LAYER. NUDGED THEM UPWARD AND MAX HEAT INDICES ARE CURRENTLY IN THE MID 90S. THE CURRENT RIDGING IS KEEPING THE AREA DRY THIS MORNING...BUT THEN THE DAYTIME HEATING AND THE LINGERING HUMIDITY ALONG WITH A WEAK SHORTWAVE MOVING THRU...WILL CREATE MORE SCT SHOWERS/TSTMS THIS AFTERNOON. THE COVERAGE OF THE ACTIVITY WILL NOT BE AS MUCH AS YESTERDAY...BUT THERE WILL BE ENOUGH TO KEEP THE CHC POPS IN THE FCST. THE UPPER WINDS WILL INCREASE SOMEWHAT THIS AFTERNOON...SO THE STORMS WILL HAVE A GREATER FORWARD (ERLY) MOTION. TEMPERATURES WILL ONCE AGAIN REACH THE UPPER 80S TO LOW 90S ACROSS THE AREA. THIS WILL BE DAY2 OF OUR LATEST (EXPECTED) HEAT WAVE. DEW POINT READINGS WILL PROBABLY BE A BIT LESS THAN YDAY WITH A MORE WRLY FLOW ALOFT. WE DO NOT EXPECT THAT THE APPARENT TEMPS WILL BE GREAT ENOUGH FOR ANY HEAT RELATED HEADLINES TODAY...BUT CARE SHOULD STILL BE EXERCISED FOR THOSE WHO WILL BE OUTDOORS TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... ANY LINGERING SHOWER/TSTM ACTIVITY WILL DIMINISH THIS EVENING AND ANOTHER MILD/HUMID...BUT DRY FCST IS EXPECTED. LOWS WILL ONLY DROP INTO THE LOW 70S ACROSS THE METRO AREAS AND THE DELMARVA...WHILE UPPER 60S WILL BE FOUND ACROSS NRN NJ. PATCHY FOG IS POSSIBLE ... ESPECIALLY IN AREAS THAT RECEIVE SHOWERS TODAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... 5-WAVE MODEL GUIDANCE IS SHOWING A RATHER ROBUST BLOCKING PATTERN DEVELOPING ACROSS THE REGION. A LARGE RIDGE WILL PUSH INTO THE SOUTHWEST UNITED STATES WHILE THE RIDGING DOWNSTREAM OF OUR REGION AMPLIFIES ACROSS THE WESTERN ATLANTIC. THIS PLACES US IN A DEEPENING EAST COAST TROUGH THAT LOOKS TO DEEPEN WITH TIME. THIS WILL ALSO SLOW THE PROGRESSION OF ANY WEST-EAST MOVING SYSTEMS AND EFFECTIVELY KEEP US UNSETTLED HEADING INTO THE FIRST WEEK OF JULY. BEFORE THE BLOCKING GETS FULLY SETUP WE CONTINUE WITH A RATHER PROGRESSIVE PSEUDO-ZONAL FLOW ALOFT. THE JET STREAM STILL REMAINS LOCKED FAR TO OUR NORTH ALLOWING THE HEAT AND HUMIDITY TO CONTINUE FOR THE FIRST PART OF THE LONGTERM. THIS WILL PROVIDE THE CONTINUED ONSLAUGHT OF DIURNALLY DRIVEN CONVECTION ACROSS THE AREA WEDNESDAY AND THURSDAY. ON WEDNESDAY THE SHOWERS AND THUNDERSTORMS WILL BE WIDESPREAD WITHOUT MUCH UPPER LEVEL SUPPORT SO ORGANIZATION DOES NOT SEEM TO BE AN ISSUE THOUGH LOCALLY STRONG WIND GUSTS WITH VERY HEAVY RAIN CAN NOT BE RULED OUT. 850MB TEMPERATURES JUMP CLOSE TO 20C BUT STILL THINK THAT CLOUD COVER WILL PLAGUE THE REGION EARLIER ON WEDNESDAY THAN IN DAYS PAST. THERE COULD EVEN BE ON-GOING CONVECTION THROUGH THE MORNING HOURS TO HELP HAMPER HIGHS REACHING THE MID-90S. PLAYED IT A BIT MORE CONSERVATIVE AND WENT LOW-90S ACROSS THE METRO AREA WITH WARMER TEMPERATURES OVER THE WEST AS DOWNSLOPING SHOULD HELP TO WARM THEM A COUPLE MORE DEGREES. HEADING INTO THURSDAY WE START TO SEE THE ZONAL FLOW BREAK DOWN AS A MID-LEVEL IMPULSE DROPS ACROSS THE JET AND DRAGS TO INTO THE MID-WEST. THIS WILL ALLOW FOR VERY DEEP SOUTHWESTERLY FLOW TO SETUP ACROSS THE AREA AND WILL PUMP IN EVEN MORE MOISTURE. DECENT CYCLONIC FLOW ALOFT WILL INCREASE DURING THE DAY AS HEIGHTS BEGIN TO FALL AHEAD OF THE APPROACHING IMPULSE. THURSDAY IS SETTING UP TO BE AN ACTIVE DAY ACROSS THE REGION IN TERMS OF SEVERE WEATHER. SPC HAS PUT THE WESTERN PORTIONS OF THE CWA IN A SLIGHT RISK GIVEN THE AMOUNT OF SURFACE BASED INSTABILITY THAT WILL BE PRESENT AND BETTER UPPER LEVEL SUPPORT ALLOWING FOR MORE ORGANIZED CLUSTER OF STORMS. THURSDAY COULD ALSO BE THE LAST DAY OF 90+F WE SEE THIS WEEK, BUT THIS GREATLY DEPENDS ON THE AMOUNT OF CLOUD COVER AND THE TIMING OF THE CONVECTION. FRIDAY STILL LOOKS TO PROVIDE ANOTHER ROUND FOR SEVERE WEATHER AS THE COLD FRONT, TIED TO AN ADVANCING SURFACE LOW OVER THE GREAT LAKES, NEARS FROM THE NORTHWEST. THERE SHOULD STILL BE PLENTY OF INSTABILITY LEFT OVER FROM THURSDAY TO ALLOW FOR SURFACE BASED INITIATION DURING THE LATE MORNING AND EARLY AFTERNOON HOURS WITH A FEW BREAKS IN THE OVERALL CLOUD COVER. TEMPERATURES WILL BE A FEW DEGREES COOLER ON FRIDAY THAN THURSDAY SO WE SHOULD BE ABLE TO BREAK THE CURRENT HEAT WAVE BY THEN. THE MID-LEVEL LOW SHOULD RETROGRADE A BIT DURING THE AFTERNOON HOURS ON FRIDAY SO WE LOSE A BIT OF THE COLD POOL INTERACTION BUT WE ALSO GAIN A MORE NEGATIVELY TILTED SHORTWAVE. THIS SETUP MAY MIMIC WHAT OCCURRED LATE LAST WEEK WHERE CONVECTION BEGAN LATE MORNING AND THEN FORMED INTO A LARGE BLOB OF SLOW MOVING HEAVY SHOWERS CAUSING FLASH FLOODING. GRANTED THERE IS THE LINEAR LIFTING ALONG THE COLD FRONT BUT IT REALLY DOES NOT FLY THROUGH THE REGION AND JUST SLOWLY LIMPS THROUGH. HEADING INTO THE WEEKEND WE KEEP THE MID-LEVEL TROUGH ENTRENCHED OVER THE REGION WITH PRETTY GOOD UPPER LEVEL DYNAMICS AS MULTIPLE WAVES RIDE UP THE EASTERN SEABOARD. THE UPPER JET WILL ALSO BE IN A GOOD SPOT WITH US IN ITS RIGHT ENTRANCE REGION FOR A PROLONGED TIME PERIOD. PWATS WILL STILL REMAIN VERY LARGE AND THUS WE CONTINUE TO RUN THE RISK FOR VERY HEAVY DOWNPOURS THROUGH AT LEAST EARLY NEXT WEEK. TEMPERATURES WILL BE MORE ON THE SEASONAL SIDE FROM FRIDAY ONWARD. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. AFTER SUNRISE SKIES WILL BE MOSTLY CLR WITH LIGHT W/SW WINDS EXPECTED. DURING THE AFTERNOON...CU WILL DEVELOP ACROSS THE AREA AND SCT SHOWERS/TSTMS WILL FORM. WE ADDED TEMPO GROUPS IN FROM PHL NORTHWARD. WINDS THIS AFTERNOON W/SW AROUND 10-12 KTS. SEA BREEZE FRONT SHOULD STAY NEAR THE COAST AND BAY. THIS EVENING...SCT SHOWERS/TSTMS WILL DIMINISH BY 01-02Z AND THEN SKIES WILL BECOME MOSTLY CLR AS THEY DID MONDAY NIGHT. PATCHY FOG WILL BE POSSIBLE AGAIN AFTER MIDNIGHT. OUTLOOK... WEDNESDAY MORNING INTO THURSDAY MORNING...MOSTLY VFR WITH SHORT PERIODS OF SUB-VFR IN MORNING FOG AND/OR SCT SHOWERS/TSTMS. THURSDAY AFTERNOON THROUGH SATURDAY...MORE MVFR AND IFR CONDITIONS IN MORE NUMEROUS SHOWERS/TSTMS AS WELL AS MORNING LOW CLOUDS AND FOG. && .MARINE... THE RETURN FLOW BEHIND THE DEPARTING BERMUDA HIGH WILL KEEP A W/SW WIND ACROSS THE WATERS TODAY AND TONIGHT. WINDS/SEAS WILL REMAIN BELOW SCA CONDITIONS THRU THE PERIOD. FAIR WEATHER EXPECTED THIS MORNING...FOLLOWED BY SCT SHOWERS/TSTMS THIS AFTERNOON AND EARLY EVENING. FAIR WEATHER WILL RESUME LATER TONIGHT INTO WED MORNING. SEAS ON THE OCEAN WILL BE AROUND 2-4 FT AND 1-2 FT OVER DEL BAY. REMEMBER...WINDS AND WAVES WILL BE LOCALLY HIGHER IN TSTMS. OUTLOOK... SUB-SCA CONDITIONS ARE EXPECTED INTO THURSDAY MORNING. AFTER THAT THE FORECAST INCREASING SOUTHERLY FLOW MIGHT BRING SCA CRITERIA BASED ON SWELLS, MORE SO THAN WINDS, TO THE OCEAN WATERS LATER THURSDAY THROUGH FRIDAY. CONFIDENCE RIGHT NOW REMAINS LOWER THAN AVERAGE THAT THIS WILL OCCUR AS WAVE WATCH GUIDANCE OFTEN IS TOO BULLISH UNDER THESE REGIMES. && .CLIMATE... WE STAND A PRETTY GOOD CHANCE OF HAVING THE WETTEST JUNE ON RECORD IN PHILADELPHIA. WE LOOKED BACK AT THE 10 PREVIOUS WETTEST JUNES ON RECORD AND SAW HOW THE REST OF THE METEOROLOGICAL SUMMER WENT FORWARD. WET BEGETTED(SP) MORE WET. GIVEN HOW WET THE GFS AND ECMWF LOOK INTO THE START OF JULY THAT NOTION IS HOLDING. BOTH ENSUING MONTHS AVERAGED WETTER THAN THE CURRENT NORMALS WITH EIGHT OF THE TEN MONTHS COMBINED AVERAGING WETTER THAN NORMAL. ALL OF THE MONTHS HAD TWO INCHES OR MORE OF RAINFALL. AS FAR AS TEMPERATURES WENT, JULY AVERAGED SLIGHTLY LOWER THAN THE CURRENT NORMAL, WHILE AUGUST WAS VERY CLOSE TO THE CURRENT NORMAL. SIX OF THE TEN AUGUSTS WERE AS WARM OR WARMER THAN JULY. YEAR JULY AVG JULY AUG AVG AUGUST TEMP PCPN TEMP PCPN 1887 80.7 7.14 74.0 2.31 1906 75.6 5.33 76.2 9.56 1928 77.3 3.60 77.2 5.47 1938 77.3 6.52 78.3 4.10 1962 72.0 2.30 72.0 6.58 1969 75.1 8.33 75.2 2.66 1973 77.9 2.39 78.7 2.03 1975 76.6 6.32 77.0 2.11 2003 78.7 2.01 78.2 3.26 2006 79.4 4.27 78.1 3.93 AVG 77.1 4.82 76.5 4.20 1981-2010 NML 78.1 4.35 76.6 3.50 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...HEAVENER NEAR TERM...GIGI/O`HARA SHORT TERM...O`HARA LONG TERM...HEAVENER AVIATION...GIGI/O`HARA MARINE...GIGI/O`HARA CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
911 AM EDT TUE JUN 25 2013 .SYNOPSIS... BERMUDA RIDGE KEEPS THE REGION LOCKED IN A HOT AND HUMID AIRMASS THROUGH AT LEAST THE END OF THE WORK WEEK. A STRONG COLD FRONT WILL NEAR FROM THE NORTHWEST ON THURSDAY BUT BEGIN TO SLOW UPON ITS ARRIVAL. THE FRONT SHOULD LIMP THROUGH BY FRIDAY BUT THEN STALL TO OUR IMMEDIATE EAST THROUGH EARLY NEXT WEEK KEEPING A PROLONGED PERIOD OF UNSETTLED WEATHER. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... NOT MANY CHANGES WITH THIS ESTF UPDATE. LOOKS LIKE THE SPC WRF AND LATEST RAP ARE VERIFYING THE BEST WITH CONVECTION TO THE NORTHWEST, SO WE SCALED BACK THE TIMING OF ARRIVAL IN OUR CWA SLIGHTLY. BOTH HI RES NMM AND ARW LOOK TOO BULLISH WITH LEAD CONVECTIVE ACTIVITY. 12Z SOUNDINGS ARE AGAIN SHOWING PLENTY OF DRY AIR ABOVE THE SURFACE AND LESS OF AN INVERSION THAN YESTERDAY. SO WOULD EXPECT DEW POINTS TO DROP OFF QUICKER. FORECAST CONVECTIVE TEMPS ARE CLOSE (OR EVEN HIER) THAN SOUNDING FORECAST MAX TEMPS. THIS TOO POINTS TO WAITING FOR THE GREAT LAKES CONVECTION TO GET HERE VS HOME GROWN, THUS LATER TIMING. 500MB TEMPS ARE FORECAST TO BE ABOUT 3C WARMER THAN YESTERDAY, SO CONVECTION WILL HAVE A LESS HOSPITABLE AIR MASS TO BECOME VIGOROUS. MORNING SOUNDINGS SUGGEST MAYBE A 1-2F BUMP UP IN MAX TEMPS. THE COMBO IS STILL KEEPING OUR HEAT INDEX VALUES 90-95 BELOW HEADLINE CRITERIA FOR TODAY. FAIR WEATHER IS ACROSS THE REGION EARLY THIS MORNING AS SOME UPPER RIDGING HAS BUILT OVER THE AREA BEHIND YESTERDAYS SHORT WAVE. THIS RIDGING WILL PROBABLY KEEP THE AREA DRY THIS MORNING...BUT THEN THE DAYTIME HEATING AND THE LINGERING HUMIDITY ALONG WITH A WEAK SHORTWAVE MOVING THRU...WILL CREATE MORE SCT SHOWERS/TSTMS THIS AFTERNOON. THE COVERAGE OF THE ACTIVITY WILL NOT BE AS MUCH AS YESTERDAY...BUT THERE WILL BE ENOUGH TO KEEP THE CHC POPS IN THE FCST. THE UPPER WINDS WILL INCREASE SOMEWHAT THIS AFTERNOON...SO THE STORMS WILL HAVE A GREATER FORWARD (ERLY) MOTION. OUR CWA IS IN SPC`S GENERAL TSTM OUTLOOK FOR TODAY. TEMPERATURES WILL ONCE AGAIN REACH THE UPPER 80S TO LOW 90S ACROSS THE AREA. THIS WILL BE DAY2 OF OUR LATEST (EXPECTED) HEAT WAVE. DEW POINT READINGS WILL PROBABLY BE A BIT LESS THAN YDAY WITH A MORE WRLY FLOW ALOFT. WE DO NOT EXPECT THAT THE APPARENT TEMPS WILL BE GREAT ENOUGH FOR ANY HEAT RELATED HEADLINES TODAY...BUT CARE SHOULD STILL BE EXERCISED FOR THOSE WHO WILL BE OUTDOORS TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... ANY LINGERING SHOWER/TSTM ACTIVITY WILL DIMINISH THIS EVENING AND ANOTHER MILD/HUMID...BUT DRY FCST IS EXPECTED. LOWS WILL ONLY DROP INTO THE LOW 70S ACROSS THE METRO AREAS AND THE DELMARVA...WHILE UPPER 60S WILL BE FOUND ACROSS NRN NJ. PATCHY FOG IS POSSIBLE ... ESPECIALLY IN AREAS THAT RECEIVE SHOWERS TODAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... 5-WAVE MODEL GUIDANCE IS SHOWING A RATHER ROBUST BLOCKING PATTERN DEVELOPING ACROSS THE REGION. A LARGE RIDGE WILL PUSH INTO THE SOUTHWEST UNITED STATES WHILE THE RIDGING DOWNSTREAM OF OUR REGION AMPLIFIES ACROSS THE WESTERN ATLANTIC. THIS PLACES US IN A DEEPENING EAST COAST TROUGH THAT LOOKS TO DEEPEN WITH TIME. THIS WILL ALSO SLOW THE PROGRESSION OF ANY WEST-EAST MOVING SYSTEMS AND EFFECTIVELY KEEP US UNSETTLED HEADING INTO THE FIRST WEEK OF JULY. BEFORE THE BLOCKING GETS FULLY SETUP WE CONTINUE WITH A RATHER PROGRESSIVE PSEUDO-ZONAL FLOW ALOFT. THE JET STREAM STILL REMAINS LOCKED FAR TO OUR NORTH ALLOWING THE HEAT AND HUMIDITY TO CONTINUE FOR THE FIRST PART OF THE LONGTERM. THIS WILL PROVIDE THE CONTINUED ONSLAUGHT OF DIURNALLY DRIVEN CONVECTION ACROSS THE AREA WEDNESDAY AND THURSDAY. ON WEDNESDAY THE SHOWERS AND THUNDERSTORMS WILL BE WIDESPREAD WITHOUT MUCH UPPER LEVEL SUPPORT SO ORGANIZATION DOES NOT SEEM TO BE AN ISSUE THOUGH LOCALLY STRONG WIND GUSTS WITH VERY HEAVY RAIN CAN NOT BE RULED OUT. 850MB TEMPERATURES JUMP CLOSE TO 20C BUT STILL THINK THAT CLOUD COVER WILL PLAGUE THE REGION EARLIER ON WEDNESDAY THAN IN DAYS PAST. THERE COULD EVEN BE ON-GOING CONVECTION THROUGH THE MORNING HOURS TO HELP HAMPER HIGHS REACHING THE MID-90S. PLAYED IT A BIT MORE CONSERVATIVE AND WENT LOW-90S ACROSS THE METRO AREA WITH WARMER TEMPERATURES OVER THE WEST AS DOWNSLOPING SHOULD HELP TO WARM THEM A COUPLE MORE DEGREES. HEADING INTO THURSDAY WE START TO SEE THE ZONAL FLOW BREAK DOWN AS A MID-LEVEL IMPULSE DROPS ACROSS THE JET AND DRAGS TO INTO THE MID-WEST. THIS WILL ALLOW FOR VERY DEEP SOUTHWESTERLY FLOW TO SETUP ACROSS THE AREA AND WILL PUMP IN EVEN MORE MOISTURE. DECENT CYCLONIC FLOW ALOFT WILL INCREASE DURING THE DAY AS HEIGHTS BEGIN TO FALL AHEAD OF THE APPROACHING IMPULSE. THURSDAY IS SETTING UP TO BE AN ACTIVE DAY ACROSS THE REGION IN TERMS OF SEVERE WEATHER. SPC HAS PUT THE WESTERN PORTIONS OF THE CWA IN A SLIGHT RISK GIVEN THE AMOUNT OF SURFACE BASED INSTABILITY THAT WILL BE PRESENT AND BETTER UPPER LEVEL SUPPORT ALLOWING FOR MORE ORGANIZED CLUSTER OF STORMS. THURSDAY COULD ALSO BE THE LAST DAY OF 90+F WE SEE THIS WEEK, BUT THIS GREATLY DEPENDS ON THE AMOUNT OF CLOUD COVER AND THE TIMING OF THE CONVECTION. FRIDAY STILL LOOKS TO PROVIDE ANOTHER ROUND FOR SEVERE WEATHER AS THE COLD FRONT, TIED TO AN ADVANCING SURFACE LOW OVER THE GREAT LAKES, NEARS FROM THE NORTHWEST. THERE SHOULD STILL BE PLENTY OF INSTABILITY LEFT OVER FROM THURSDAY TO ALLOW FOR SURFACE BASED INITIATION DURING THE LATE MORNING AND EARLY AFTERNOON HOURS WITH A FEW BREAKS IN THE OVERALL CLOUD COVER. TEMPERATURES WILL BE A FEW DEGREES COOLER ON FRIDAY THAN THURSDAY SO WE SHOULD BE ABLE TO BREAK THE CURRENT HEAT WAVE BY THEN. THE MID-LEVEL LOW SHOULD RETROGRADE A BIT DURING THE AFTERNOON HOURS ON FRIDAY SO WE LOSE A BIT OF THE COLD POOL INTERACTION BUT WE ALSO GAIN A MORE NEGATIVELY TILTED SHORTWAVE. THIS SETUP MAY MIMIC WHAT OCCURRED LATE LAST WEEK WHERE CONVECTION BEGAN LATE MORNING AND THEN FORMED INTO A LARGE BLOB OF SLOW MOVING HEAVY SHOWERS CAUSING FLASH FLOODING. GRANTED THERE IS THE LINEAR LIFTING ALONG THE COLD FRONT BUT IT REALLY DOES NOT FLY THROUGH THE REGION AND JUST SLOWLY LIMPS THROUGH. HEADING INTO THE WEEKEND WE KEEP THE MID-LEVEL TROUGH ENTRENCHED OVER THE REGION WITH PRETTY GOOD UPPER LEVEL DYNAMICS AS MULTIPLE WAVES RIDE UP THE EASTERN SEABOARD. THE UPPER JET WILL ALSO BE IN A GOOD SPOT WITH US IN ITS RIGHT ENTRANCE REGION FOR A PROLONGED TIME PERIOD. PWATS WILL STILL REMAIN VERY LARGE AND THUS WE CONTINUE TO RUN THE RISK FOR VERY HEAVY DOWNPOURS THROUGH AT LEAST EARLY NEXT WEEK. TEMPERATURES WILL BE MORE ON THE SEASONAL SIDE FROM FRIDAY ONWARD. && .AVIATION /13Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. AFTER SUNRISE SKIES WILL BE MOSTLY CLR WITH LIGHT W/SW WINDS EXPECTED. DURING THE AFTERNOON...CU WILL DEVELOP ACROSS THE AREA AND SCT SHOWERS/TSTMS WILL FORM. THE PROB30 FCST FROM EARLIER WAS LEFT IN THE 06Z TAFS. WINDS THIS AFTERNOON W/SW AROUND 10-12 KTS. THIS EVENING...SCT SHOWERS/TSTMS WILL DIMINISH BY 01-02Z AND THEN SKIES WILL BECOME MOSTLY CLR AS THEY DID MONDAY NIGHT. PATCHY FOG WILL BE POSSIBLE AGAIN AFTER MIDNIGHT. OUTLOOK... WEDNESDAY MORNING INTO THURSDAY MORNING...MOSTLY VFR WITH SHORT PERIODS OF SUB-VFR IN MORNING FOG AND/OR SCT SHOWERS/TSTMS. THURSDAY AFTERNOON THROUGH SATURDAY...MORE MVFR AND IFR CONDITIONS IN MORE NUMEROUS SHOWERS/TSTMS AS WELL AS MORNING LOW CLOUDS AND FOG. && .MARINE... THE RETURN FLOW BEHIND THE DEPARTING BERMUDA HIGH WILL KEEP A W/SW WIND ACROSS THE WATERS TODAY AND TONIGHT. WINDS/SEAS WILL REMAIN BELOW SCA CONDITIONS THRU THE PERIOD. FAIR WEATHER EXPECTED THIS MORNING...FOLLOWED BY SCT SHOWERS/TSTMS THIS AFTERNOON AND EARLY EVENING. FAIR WEATHER WILL RESUME LATER TONIGHT INTO WED MORNING. SEAS ON THE OCEAN WILL BE AROUND 2-4 FT AND 1-2 FT OVER DEL BAY. REMEMBER...WINDS AND WAVES WILL BE LOCALLY HIGHER IN TSTMS. OUTLOOK... SUB-SCA CONDITIONS ARE EXPECTED INTO THURSDAY MORNING. AFTER THAT THE FORECAST INCREASING SOUTHERLY FLOW MIGHT BRING SCA CRITERIA BASED ON SWELLS, MORE SO THAN WINDS, TO THE OCEAN WATERS LATER THURSDAY THROUGH FRIDAY. CONFIDENCE RIGHT NOW REMAINS LOWER THAN AVERAGE THAT THIS WILL OCCUR AS WAVE WATCH GUIDANCE OFTEN IS TOO BULLISH UNDER THESE REGIMES. && .CLIMATE... WE STAND A PRETTY GOOD CHANCE OF HAVING THE WETTEST JUNE ON RECORD IN PHILADELPHIA. WE LOOKED BACK AT THE 10 PREVIOUS WETTEST JUNES ON RECORD AND SAW HOW THE REST OF THE METEOROLOGICAL SUMMER WENT FORWARD. WET BEGETTED(SP) MORE WET. GIVEN HOW WET THE GFS AND ECMWF LOOK INTO THE START OF JULY THAT NOTION IS HOLDING. BOTH ENSUING MONTHS AVERAGED WETTER THAN THE CURRENT NORMALS WITH EIGHT OF THE TEN MONTHS COMBINED AVERAGING WETTER THAN NORMAL. ALL OF THE MONTHS HAD TWO INCHES OR MORE OF RAINFALL. AS FAR AS TEMPERATURES WENT, JULY AVERAGED SLIGHTLY LOWER THAN THE CURRENT NORMAL, WHILE AUGUST WAS VERY CLOSE TO THE CURRENT NORMAL. SIX OF THE TEN AUGUSTS WERE AS WARM OR WARMER THAN JULY. YEAR JULY AVG JULY AUG AVG AUGUST TEMP PCPN TEMP PCPN 1887 80.7 7.14 74.0 2.31 1906 75.6 5.33 76.2 9.56 1928 77.3 3.60 77.2 5.47 1938 77.3 6.52 78.3 4.10 1962 72.0 2.30 72.0 6.58 1969 75.1 8.33 75.2 2.66 1973 77.9 2.39 78.7 2.03 1975 76.6 6.32 77.0 2.11 2003 78.7 2.01 78.2 3.26 2006 79.4 4.27 78.1 3.93 AVG 77.1 4.82 76.5 4.20 1981-2010 NML 78.1 4.35 76.6 3.50 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...HEAVENER NEAR TERM...GIGI/O`HARA SHORT TERM...O`HARA LONG TERM...HEAVENER AVIATION...GIGI/O`HARA MARINE...GIGI/O`HARA CLIMATE...
AREA FORECAST DISCUSSION
NWS GRAY ME
1123 AM EDT TUE JUN 25 2013 .SYNOPSIS... HOT AND HUMID AIR CONTINUES TO BE PUSHED NORTH INTO NEW ENGLAND AS SOUTHWEST FLOW PERSISTS OVER THE AREA. THE THREAT FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE. BY THURSDAY AND FRIDAY THERE IS A CHANCE FOR A MORE CONSISTENT RAIN AS WEAK LOW PRESSURE DEVELOPS TO OUR WEST AND LIFTS NORTHEAST INTO QUEBEC. THIS WILL ALSO SHIFT THE WINDS MORE ONSHORE...WITH COOLER TEMPERATURES AT THE END OF THE WEEK...ALTHOUGH THE HUMIDITY WILL NOT DROP OFF THAT MUCH. WE WILL SWITCH BACK TO A SOUTHERLY FLOW FOR THE WEEKEND...WITH WARMER AND CONTINUED HUMID CONDITIONS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 11 AM...STILL LOOKING FOR THE DEVELOPMENT OF SEVERE STORMS THIS AFTERNOON. 12Z KGYX RAOB SHOWS G0OD CAPPING...BUT THIS SHOULD WEAKEN EARLY THIS AFTERNOON...AS WEAK 500MB WAVE TRACKS JUST TO THE N OF THE CWA...AND 500MB HEIGHTS FALL. ALSO...WILL SEE UVV DEVELOP NEAR JET ENTRY REGION PASSING OVER NRN ZONES. EXPECTING SCT-BKN LINE OF STORMS TOP DEVELOP TOUR WEST AND TRACK E ACROSS THE AREA MID-LATE AFTERNOON...PRODUCING MAINLY STRONG WINDS. COULD SEE SOME PULSE TYPE STORMS AHEAD THIS LINE AS WELL. HEAVY RAIN IS ANOTHER PROBLEM AS PWATS ARE FORECAST TO INCREASE TO 1.5-1.8 LATER TODAY. PREVIOUSLY...LATEST HRRR RUN CONTINUES TO INDICATE CONVECTIVE INITIATION BEGINNING AROUND 18Z OVER FAR NORTHERN AND WESTERN PORTIONS OF THE FORECAST AREA. THIS IS IN RESPONSE TO SHORT WAVE RACING ACROSS SOUTHERN CANADA. WIND FIELDS WILL BE INCREASING (AND UNIDIRECTIONAL) WITH THIS FEATURE. WITH STEEP LOW LEVEL LAPSE RATES AND HIGH SURFACE DEW POINTS IN PLACE...CONVECTION TODAY WILL BE MORE ORGANIZED THAN YESTERDAY AS THE WIND MAX APPROACHES FROM THE NORTHWEST. DAMAGING STRAIGHT LINE WINDS ARE POSSIBLE IN ISOLATED STORMS...WITH LARGE HAIL POSSIBLE IN ANY OF THE STRONGER STORMS AS CAPE VALUES RAPIDLY CLIMB WITH GOOD SOLAR HEATING TODAY. HAVE ENHANCED WORDING IN THE GRIDS. PRECIPITABLE WATER VALUES REMAIN VERY HIGH. SOME OF THE SHOWERS AND STORMS MAY DROP VERY HEAVY RAIN IN A SHORT PERIOD OF TIME. STORMS WILL BE RELATIVELY FAST MOVING...BUT TRAINING OF SHOWERS WILL NEED TO BE MONITORED. AN AIR QUALITY ALERT WILL REMAIN IN EFFECT FOR TODAY...UNTIL 11 PM. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... WITH LOW LEVEL MOISTURE IN PLACE...AFTER AFTERNOON AND EVENING RAINS...PATCHY FOG WILL DEVELOP ONCE AGAIN ACROSS THE REGION TONIGHT. USED A BLEND OF MAV/MET MOS FOR OVERNIGHT MIN TEMPERATURES. MORE SHOWERS AND STORMS ARE POSSIBLE WEDNESDAY AFTERNOON AS A BACKDOOR COLD FRONT MOVES SOUTH ACROSS MAINE AND NEW HAMPSHIRE. SOME OF THESE STORMS MAY BE LOCALLY STRONG AS WELL. READINGS OVER SOUTHERN NEW HAMPSHIRE WILL SHOOT UP QUICKLY AHEAD OF THE SURFACE COLD FRONT...SO A HEAT WAVE (3 CONSECUTIVE DAYS AT OR ABOVE 90 DEGREES) IS STILL POSSIBLE OVER THIS REGION. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... THE MODELS ARE IN DECENT AGREEMENT WELL INTO NEXT WEEK ON EVOLVING LONGWAVE PATTERN. A SERIES OF SHORTWAVES RIDING OVER THE TOP OF THE WESTERN CONUS RIDGE WILL CARVE OUT A DEEP TROUGH ACROSS THE EAST BY THE UPCOMING WEEKEND. THE OVERALL THEME WILL BE WARM...HUMID...AND WET FOR THE FORECAST PERIOD. IN THE DAILIES...LOW PRESSURE WILL MOVE EAST FROM THE GREAT LAKES ON THURSDAY THEN SLOW DOWN AND LINGER ACROSS THE NORTHEAST THROUGH EARLY NEXT WEEK PRODUCING WARM, HUMID, AND WET WEATHER ACROSS THE AREA. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... SHORT TERM... MORNING FOG IN SHELTERED VALLEYS WILL LIFT EARLY THIS MORNING. THIS WILL ALLOW FOR SUNNY AND HUMID CONDITIONS...WITH THE DEVELOPMENT OF MORE SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. PATCHY FOG TO DEVELOP AGAIN TONIGHT WITH LOCAL IFR CONDITIONS...FOLLOWED BY MORE SHOWERS AND STORMS WEDNESDAY AFTERNOON. LONG TERM... THU - SAT...AREAS OF MVFR LIKELY IN SHOWERS AND THUNDERSTORMS. && .MARINE... SHORT TERM... SOUTHWEST FLOW CONTINUES THROUGH TUESDAY BUT SHOULD KEEP CONDITIONS BELOW ADVISORY LEVELS. LONG TERM... FRI - SAT...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$ SYNOPSIS... NEAR TERM...CEMPA SHORT TERM... LONG TERM... AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS CARIBOU ME
956 AM EDT TUE JUN 25 2013 .SYNOPSIS... STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE EXPECTED TODAY AS A FRONTAL BOUNDARY SAGS SOUTHWARD ACROSS THE AREA. UNSETTLED CONDITIONS WILL PERSIST THROUGH THE REMAINDER OF THE WEEK AND UPCOMING WEEKEND AS A BROAD AND SLOW MOVING LOW PRESSURE SYSTEM FROM THE GREAT LAKES MOVES EASTWARD. && .NEAR TERM /THROUGH TONIGHT/... 930AM UPDATE... CONVECTIVE ACTIVITY REMAINS ON TRACK TO DEVELOP EARLY TO MID AFTERNOON COINCIDENT WITH AFTERNOON HEATING IN A VERY HUMID AIR MASS. THIS HEATING ALSO COINCIDE WITH THE ARRIVAL OF AN UPPER TROUGH AND THE RIGHT ENTRANCE REGION OF AN UPPER JET. THESE FACTORS WILL CONTRIBUTE TO INSTABILITY SUFFICIENT FOR STRONG TO SEVERE THUNDERSTORMS WITH DAMAGING WINDS...HAIL AND HEAVY RAIN. THUNDERSTORMS WILL WIND DOWN LATER IN THE EVENING. UPDATE 0520L: FEW INITIAL SHOWERS/TSTM INTO XTRM NRN AND WRN MAINE ATTM... ADJUSTED POPS/HRLY TEMPS TO BETTER FIT CURRENT AND EXPECTED TRENDS NXT FEW HRS... QUIET ACROSS THE FA FOR NOW AS WEAKENING BAND OF SHOWERS HAS EXITED OUR SERN AREAS WHILE ANOTHER CLUSTER OF SHOWERS AND TSTMS IS NOTED NW-N OF THE FA ALONG AND JUST W OF THE ST LAWRENCE... NR STATIONARY FRONTAL BNDRY N OF THE REGION XTNDG WNW-ESE FROM JAMES BAY ACROSS THE GASPE AND INTO THE GULF OF THE ST LAWRENCE. SEVERAL WEAK LOWS CONT TO SLIDE ESEWRD ALONG THIS BNDRY W/ THE STRONGEST OF THESE NR THE SERN TIP OF JAMES BAY ATTM. MODELS IN FAIRLY GOOD AGREEMENT AND ALLOW THIS SFC LOW NR JAMES BAY TO DROP SEWRD ALONG THIS FRONTAL BNDRY W/ THE FRONTAL BNDRY SAGGING SWRD ACROSS THE AREA FROM LATE TDY THRU TNGT. VRY WARM/HUMID AND UNSTABLE AIR IN PLACE ACROSS THE AREA S OF THIS BNDRY W/ SBCAPES FCST FROM 1000-2500 J/KG AND THIS WILL COMBINE W/ STRONG SFC AND UPPER DYNAMICS AS THIS FRONTAL BNDRY AND LOW PRES SAG SEWRD TOWARDS THE AREA LATER TDY TO PRODUCE THE THREAT OF STRONG TO PSBLY SEVERE TSTMS ACROSS THE AREA. CURRENTLY THE SPC HAS ALL BUT OUR DOWNEAST AREAS IN A SLIGHT RISK FOR SVR W/ DAMAGING WNDS THE PRIMARY THREAT. INITIAL ACTIVITY NW-N OF THE AREA IS FCST BY THE SHORTER TERM MODEL GUIDANCE LIKE THE HRRR AND RUC TO WEAKEN AND DISSIPATE AS IT REACHES OUR FAR NRN AREAS ERLY THIS AM BUT NOT SURE ABOUT THIS... IN ANY CASE...APPEARS STRONGER ACTIVITY WILL DVLP LATER THIS AM THRU THE AFTN HRS W/ HGHST POPS ACROSS THE N AND E CENTRAL AREAS IN TO THE EVE HRS W/ LOWEST POPS FAR SW. WILL CARRY MENTION OF SVR ALONG W/ ENHANCED WORDING FOR HVY RAIN/DAMAGING WNDS AND SMALL HAIL... FOR TNGT...GUIDANCE SUGGESTS THIS BNDRY WILL BE JUST S AND W OF THE FA BY ERLY WED W/ WEAK LOW PRES CNTRS OVR ERN NS...SRN MAINE AND SWRN QUEBEC. HIGH PRES W/ SOME DRIER AIR MAY TRY TO NUDE INTO FAR NERN AREAS BY LATE TNGT/ERLY WED... EXPECT ANOTHER WARM AND MUGGY DAY TDY W/ HIGH TEMPS LARGELY DEPENDENT ON CLD CVR. THINKING THERE WILL BE SOME SUN N AND NE W/ MORE PREVALENT SUNSHINE S AND W. WILL ADVERTISE HIGHS INTO THE LOWER 80S N W/ NR 90 PSBL SRN AREAS AWAY FROM THE COAST. ANOTHER WARM AND MUGGY NGT TNGT ACROSS RN AND WRN AREAS W/ SOME COOLER AND DRIER AIR LIKELY WORKING INTO NERN AREAS. PLENTY OF LOW LEVEL MOISTURE AND RATHER LGT WNDS SUGGESTS THE THREAT OF FOG TNGT ACROSS MUCH OF THE REGION... && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AN H5 UPPER LOW DEEPENS ACROSS THE GREAT LAKES REGION DURING THIS TIME FRAME. THIS WILL ALLOW AMPLE MOISTURE TO MOVE INTO NORTHERN NEW ENGLAND. EXPECT PERIODS OF SHOWERS BOTH DAYS. HIGHS WILL BE NEAR NORMAL ON WEDNESDAY AND MUCH BELOW NORMAL ON THURSDAY. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AN H5 UPPER LOW SLOWLY PROGRESSES INTO THE NORTHEAST U.S. LATE THIS WEEK AND THEN LIFTS INTO QUEBEC THIS WEEKEND. THIS ALLOWS THE DAMP WEATHER PATTERN TO PERSIST. THURSDAY NIGHT AND FRIDAY ARE FORECAST TO BE PARTICULARLY WET WITH PERIODS OF RAIN. TEMPERATURES WILL GRADUALLY WARM BACK TO SEASONAL LEVELS BY THE WEEKEND. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... NEAR TERM: PATCHY FOG ERLY THIS AM MAY RESULT IN SOME MVFR TO IFR CONDS UP UNTIL OR SHORTLY AFTER SUNRISE. MAINLY VFR CONDS ARE THEN EXPECTED OUTSIDE OF ANY SHOWERS/TSTMS W/ MVFR/IFR DURING THIS ACTIVITY. PATCHY TO AREAS OF FOG EXPECTED AGAIN TNGT ALONG W/ A THREAT OF SHOWERS MAINLY ACROSS THE SRN HALF OF THE FA. SHORT TERM: MVFR AND POSSIBLY IFR CIGS AND VSBYS ARE EXPECTED AT TAF SITES WITH SHOWERS...RAIN AND FOG. && .MARINE... NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THRU TONIGHT. VISIBILITIES COULD BE REDUCED IN PATCHY FOG TODAY...THEN IN AREAS OF FOG AND ANY SHOWERS/THUNDERSTORMS LATER TODAY AND TONIGHT. SHORT TERM: NO HEADLINES ARE FORECAST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...KHW/MCW SHORT TERM...OKULSKI LONG TERM...OKULSKI AVIATION...KHW/MCW/OKULSKI MARINE...KHW/MCW/OKULSKI
AREA FORECAST DISCUSSION
NWS GRAY ME
655 AM EDT TUE JUN 25 2013 .SYNOPSIS... HOT AND HUMID AIR CONTINUES TO BE PUSHED NORTH INTO NEW ENGLAND AS SOUTHWEST FLOW PERSISTS OVER THE AREA. THE THREAT FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE. BY THURSDAY AND FRIDAY THERE IS A CHANCE FOR A MORE CONSISTENT RAIN AS WEAK LOW PRESSURE DEVELOPS TO OUR WEST AND LIFTS NORTHEAST INTO QUEBEC. THIS WILL ALSO SHIFT THE WINDS MORE ONSHORE...WITH COOLER TEMPERATURES AT THE END OF THE WEEK...ALTHOUGH HUMIDITY`S WILL NOT DROP OFF THAT MUCH. WE WILL SWITCH BACK TO A SOUTHERLY FLOW FOR THE WEEKEND...WITH WARMER AND CONTINUED HUMID CONDITIONS. && .NEAR TERM /THROUGH TONIGHT/... UPDATE... HAVE MADE TWEAKS TO THE GRIDS BASED ON LATEST SATELLITE IMAGES AND CURRENT TEMPERATURE AND DEW POINTS. PARTLY TO MOSTLY SUNNY CONDITIONS WILL CONTINUE UNTIL SHOWERS AND THUNDERSTORMS DEVELOP DURING THE AFTERNOON HOURS. PREV DISC... "SUPERMOON" TIDES REACHED 12 FEET IN PORTLAND EARLY THIS MORNING... LATEST HRRR RUN CONTINUES TO INDICATE CONVECTIVE INITIATION BEGINNING AROUND 18Z OVER FAR NORTHERN AND WESTERN PORTIONS OF THE FORECAST AREA. THIS IS IN RESPONSE TO SHORT WAVE RACING ACROSS SOUTHERN CANADA. WIND FIELDS WILL BE INCREASING (AND UNIDIRECTIONAL) WITH THIS FEATURE. WITH STEEP LOW LEVEL LAPSE RATES AND HIGH SURFACE DEW POINTS IN PLACE...CONVECTION TODAY WILL BE MORE ORGANIZED THAN YESTERDAY AS THE WIND MAX APPROACHES FROM THE NORTHWEST. DAMAGING STRAIGHT LINE WINDS ARE POSSIBLE IN ISOLATED STORMS...WITH LARGE HAIL POSSIBLE IN ANY OF THE STRONGER STORMS AS CAPE VALUES RAPIDLY CLIMB WITH GOOD SOLAR HEATING TODAY. HAVE ENHANCED WORDING IN THE GRIDS. PRECIPITABLE WATER VALUES REMAIN VERY HIGH. SOME OF THE SHOWERS AND STORMS MAY DROP VERY HEAVY RAIN IN A SHORT PERIOD OF TIME. STORMS WILL BE RELATIVELY FAST MOVING...BUT TRAINING OF SHOWERS WILL NEED TO BE MONITORED. AN AIR QUALITY ALERT WILL REMAIN IN EFFECT FOR TODAY...UNTIL 11 PM. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... WITH LOW LEVEL MOISTURE IN PLACE...AFTER AFTERNOON AND EVENING RAINS...PATCHY FOG WILL DEVELOP ONCE AGAIN ACROSS THE REGION TONIGHT. USED A BLEND OF MAV/MET MOS FOR OVERNIGHT MIN TEMPERATURES. MORE SHOWERS AND STORMS ARE POSSIBLE WEDNESDAY AFTERNOON AS A BACKDOOR COLD FRONT MOVES SOUTH ACROSS MAINE AND NEW HAMPSHIRE. SOME OF THESE STORMS MAY BE LOCALLY STRONG AS WELL. READINGS OVER SOUTHERN NEW HAMPSHIRE WILL SHOOT UP QUICKLY AHEAD OF THE SURFACE COLD FRONT...SO A HEAT WAVE (3 CONSECUTIVE DAYS AT OR ABOVE 90 DEGREES) IS STILL POSSIBLE OVER THIS REGION. && .LONG TERM /THURSDAY THROUGH MONDAY/... THE MODELS ARE IN DECENT AGREEMENT WELL INTO NEXT WEEK ON EVOLVING LONGWAVE PATTERN. A SERIES OF SHORTWAVES RIDING OVER THE TOP OF THE WESTERN CONUS RIDGE WILL CARVE OUT A DEEP TROUGH ACROSS THE EAST BY THE UPCOMING WEEKEND. THE OVERALL THEME WILL BE WARM...HUMID...AND WET FOR THE FORECAST PERIOD. IN THE DAILIES...LOW PRESSURE WILL MOVE EAST FROM THE GREAT LAKES ON THURSDAY THEN SLOW DOWN AND LINGER ACROSS THE NORTHEAST THROUGH EARLY NEXT WEEK PRODUCING WARM, HUMID, AND WET WEATHER ACROSS THE AREA. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... SHORT TERM... MORNING FOG IN SHELTERED VALLEYS WILL LIFT EARLY THIS MORNING. THIS WILL ALLOW FOR SUNNY AND HUMID CONDITIONS...WITH THE DEVELOPMENT OF MORE SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED. PATCHY FOG TO DEVELOP AGAIN TONIGHT WITH LOCAL IFR CONDITIONS...FOLLOWED BY MORE SHOWERS AND STORMS WEDNESDAY AFTERNOON. LONG TERM... THU - SAT...AREAS OF MVFR LIKELY IN SHOWERS AND THUNDERSTORMS. && .MARINE... SHORT TERM... SOUTHWEST FLOW CONTINUES THROUGH TUESDAY BUT SHOULD KEEP CONDITIONS BELOW ADVISORY LEVELS. LONG TERM... FRI - SAT...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...NONE. && $$
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1102 AM CDT Tue Jun 25 2013 .UPDATE... Issued at 1101 AM CDT TUE JUN 25 2013 Thunderstorm activity across eastern Kansas has persisted into the late morning hours, casting showers and cloud cover off to the northeast across our forecast area. While the intensity of the storms has come down over the past couple of hours, they also continue to regenerate on the back edge of the line; which appears due to strong moisture transport across central and eastern Kansas. Short range models other than the RUC are not picking up on this continued development at this time. Focusing on moisture transport, thoughts are that storms could keep redeveloping in eastern Kansas through noon, after which they should decay through the early afternoon as the focus for the transport moves north into eastern Nebraska and Iowa. Cast of showers and isolated embedded thunderstorms are all that is expected from this morning activity. Otherwise, looking at temperatures, have shaved a degree or two off the going highs for today as the cloud cover has been very persistent, but with some potential for the sun to come out by the early to mid-afternoon hours, thoughts are it will get hot and steamy fast. && .SHORT TERM...(Today through Thursday) Issued at 405 AM CDT TUE JUN 25 2013 Challenge for today continues to be chances of precipitation through this afternoon as a nocturnal MCS propagates across central Kansas this morning. The 00Z sounding from KTOP showed ample dry layer such that severe winds were reported with very little convection or rain associated. Upstream of that a short wave trough and low level jet...along with around 8 deg K/KM mid level lapse rates supported upscale growth of an MCS that is producing severe winds as well. This will be the area to monitor as it moves eastward towards the CWA. At this time the storm appears to be splitting with a southern area taking on a more discrete...almost super cellular mode. Given the 0-6km shear in EAX CWA of around 40kts...will have to monitor this activity closely for potential severe threat. The HRRR favors maintaining the area although weakening somewhat after sunrise. The surface winds ahead of this area are decent enough to believe that the boundary layer is well mixed even if the convection itself is elevated. The 500 mb flow will still be at least slightly cyclonic and with the low level moisture and associated CAPE values around 2000 J/KG along with weak short wave ripples in the flow...therefore a chance of convection will last through the day today. As the thermal ridge builds into the area though...the chances for precipitation will decrease with the increased heating of the column late this evening through the remainder of the short term. All models show the upper ridge significantly amplifying over the western half of the US by tomorrow afternoon...so as the nose of the thermal ridge edges into the area...we will have heat indices in the 103F to 106F range on Wednesday. Will not issue a headline at this time because if there is another MCS overnight...some debris cloudiness could limit the temperatures/heat indices. As the ridge amplifies to the west the flow will eventually turn more northwesterly so we will begin to see slight relief by Thursday. Given this flow and cap in place...precipitation chances decrease as well during Thursday. The exception is a possible MCS that may from over eastern Iowa and clip the northeast corner. .LONG TERM...(Friday through Monday) Issued at 405 AM CDT TUE JUN 25 2013 Northwest flow will prevail through this period as a the ridge/trough pattern amplifies across the CONUS. A weak front should have moved through the area by Friday morning with scattered convection lingering into the day. But the bigger effect of the front will be to cool dewpoints down into the lower 60s or even the 50s. As we see a great influence from the eastern trough, temperatures aloft cool down and thickness values decrease substantially. So will also see a nice cool down in the surface temperatures by Saturday into the first half of next week, temperatures look to very close to normal, with highs in the lower to middle 80s. And when combined with the much more comfortable dewpoints, it looks like we`ll see couple days of pleasant summer weather. With regards to precipitation chances, northwest flow is notoriously tricky for timing and placing precipitation chances. At this time, there isn`t a great signal to say that any certain period of time has a greater chance of precipitation than any other period of time. So instead of carrying some mention of precipitation through the bulk of the extended range, have trimmed POPs out until there is a better signal. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 550 AM CDT TUE JUN 25 2013 Line of storms in eastern Kansas moving towards the east at around 32kts. Main challenge is how much this area of activity will hold together as it reaches the terminals. Given the evolution...believe it has a good chance so going with tempo group. Expect the storms to be fairly weak and bases high so keeping the visibility at 5SM and the CB deck around 8K feet. Will closely monitor as daybreak approaches. Otherwise...winds will also be a challenge today...gusty from the south through the period. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...Cutter SHORT TERM...Adolphson LONG TERM...CDB AVIATION...Adolphson
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
558 AM CDT Tue Jun 25 2013 .SHORT TERM...(Today through Thursday) Issued at 405 AM CDT TUE JUN 25 2013 Challenge for today continues to be chances of precipitation through this afternoon as a nocturnal MCS propagates across central Kansas this morning. The 00Z sounding from KTOP showed ample dry layer such that severe winds were reported with very little convection or rain associated. Upstream of that a short wave trough and low level jet...along with around 8 deg K/KM mid level lapse rates supported upscale growth of an MCS that is producing severe winds as well. This will be the area to monitor as it moves eastward towards the CWA. At this time the storm appears to be splitting with a southern area taking on a more discrete...almost supercellular mode. Given the 0-6km shear in EAX CWA of around 40kts...will have to monitor this activity closely for potential severe threat. The HRRR favors maintaining the area although weakening somewhat after sunrise. The surface winds ahead of this area are decent enough to believe that the boundary layer is well mixed even if the convection itself is elevated. The 500 mb flow will still be at least slightly cyclonic and with the low level moisture and associated CAPE values around 2000 J/KG along with weak short wave ripples in the flow...therefore a chance of convection will last through the day today. As the thermal ridge builds into the area though...the chances for precipitation will decrease with the increased heating of the column late this evening through the remainder of the short term. All models show the upper ridge significantly amplifying over the western half of the US by tomorrow afternoon...so as the nose of the thermal ridge edges into the area...we will have heat indices in the 103F to 106F range on Wednesday. Will not issue a headline at this time because if there is another MCS overnight...some debris cloudiness could limit the temperatures/heat indices. As the ridge amplifies to the west the flow will eventually turn more northwesterly so we will begin to see slight relief by Thursday. Given this flow and cap in place...precipitation chances decrease as well during Thursday. The exception is a possible MCS that may from over eastern Iowa and clip the northeast corner. .LONG TERM...(Friday through Monday) Issued at 405 AM CDT TUE JUN 25 2013 Northwest flow will prevail through this period as a the ridge/trough pattern amplifies across the CONUS. A weak front should have moved through the area by Friday morning with scattered convection lingering into the day. But the bigger effect of the front will be to cool dewpoints down into the lower 60s or even the 50s. As we see a great influence from the eastern trough, temperatures aloft cool down and thickness values decrease substantially. So will also see a nice cool down in the surface temperatures by Saturday into the first half of next week, temperatures look to very close to normal, with highs in the lower to middle 80s. And when combined with the much more comfortable dewpoints, it looks like we`ll see couple days of pleasant summer weather. With regards to precipitation chances, northwest flow is notoriously tricky for timing and placing precipitation chances. At this time, there isn`t a great signal to say that any certain period of time has a greater chance of precipitation than any other period of time. So instead of carrying some mention of precipitation through the bulk of the extended range, have trimmed POPs out until there is a better signal. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 550 AM CDT TUE JUN 25 2013 Line of storms in eastern Kansas moving towards the east at around 32kts. Main challenge is how much this area of activity will hold together as it reaches the terminals. Given the evolution...believe it has a good chance so going with tempo group. Expect the storms to be fairly weak and bases high so keeping the visibility at 5SM and the CB deck around 8K feet. Will closely monitor as daybreak approaches. Otherwise...winds will also be a challenge today...gusty from the south through the period. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ SHORT TERM...Adolphson LONG TERM...CDB AVIATION...Adolphson
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
700 AM EDT TUE JUN 25 2013 .SYNOPSIS... BERMUDA HIGH PRESSURE CENTERED WELL OFFSHORE WILL REMAIN IN PLACE INTO THE WEEKEND...WHILE WEAK UPPER IMPULSES TRACK JUST NORTH OF THE AREA. THIS WILL CONTINUE THE WARM AND HUMID CONDITIONS ACROSS THE AREA...WITH GOOD CHANCES FOR SHOWERS AND THUNDERSTORMS EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 615 AM TUESDAY...MODELS INDICATE RATHER LOW AMPLITUDE IE. FLAT MID AND UPPER LEVEL RIDGING EXTENDING NW ACROSS THE AREA FROM THE BASE OR CENTER LOCATED OVER THE OFFSHORE WATERS OFF THE SE U.S. COAST. MODELS INDICATE WEAK MID-LEVEL TROFFINESS ACROSS THE SE STATES WHICH WILL LIKELY BE ENOUGH TO AID IN FIRING DIURNALLY DRIVEN CONVECTION. THE SEA BREEZE AND OUTFLOWS WILL BE THE OTHER AIDS TO KEEP CONVECTION FIRING THROUGHOUT THE DAY AND INTO THE EVENING. LATEST HRRR DOES INDICATE CONVECTION TO FIRE AROUND SUNRISE BUT NOT BOUGHT ON ITS WIDESPREAD COVERAGE THAT EARLY. THINKING IS SOMEWHAT SIMILAR TO MONDAY CONCERNING POPS IN THE 30-50 PERCENT RANGE BY MID MORNING AND LASTING THROUGH MID- EVENING. NAMBUFR SOUNDINGS INDICATE 1.75 TO 2.00 PRECIPITABLE WATERS ACROSS THE FA ONCE AGAIN. THEREFORE...THE MAIN THREAT FROM TODAYS CONVECTION WILL BE THE HEAVY DOWNPOURS ACROSS GROUNDS THAT HAVE BECOME SOMEWHAT SATURATED FROM THE RECENT RAINS OF THE PAST FEW DAYS. WILL ONCE AGAIN HAVE A LOW DIURNAL RANGE BETWEEN MAX AND MIN TEMPS DUE TO CLOUDS AND THE PCPN THREAT. STAYED ON THE LOWER SIDE OF MODEL MOS GUIDANCE FOR TODAYS MAXES...AND THE HIGHER SIDE OF MODEL MOS FOR TONIGHTS LOWS. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...PERSISTENCE THE RULE FOR THE SHORT TERM AS SUMMERTIME PATTERN REMAINS IN PLACE WITH BERMUDA HIGH OFFSHORE AND FLAT RIDGING CONTINUING ALOFT. THIS CREATES A WARM...HUMID...AND ACTIVE PATTERN AS TEMPS RISE INTO THE LOW 90S AWAY FROM THE COAST...WITH LOWS FALLING ONLY INTO THE LOW 70S. HOWEVER...THERE WILL LIKELY BE CONSIDERABLE VARIABILITY EACH DAY AS CONVECTION LOOKS TO BE SCATTERED-TO-WIDESPREAD ACROSS THE AREA. IN ADDITION TO THE FLAT 5H RIDGING WHICH SLOWLY BEGINS TO BREAK DOWN...A WEAK VORT WILL CROSS OVERHEAD ON WEDNESDAY. TIMING THIS FEATURE IS STILL UNCERTAIN...AND THERE WILL BE A RACE BETWEEN SUBSIDENCE BEHIND THE VORT...AND AFTN INSTABILITY. ASSUMING THE VORT MOVES OFFSHORE EARLY...WILL CAP POP AT LOW-CHC...AND WEDNESDAY MAY BE THE DRIEST DAY OF THE WEEK. BY THURSDAY...MID LEVEL LAPSE RATES STEEPEN CONSIDERABLY AND MORE WIDESPREAD CONVECTION IS ANTICIPATED IN A CONTINUED HIGHLY UNSTABLE ENVIRONMENT. WHILE SEVERE CONVECTION LOOKS UNLIKELY...OR ISOLATED AT WORST...HEAVY RAIN AND FLOODING WILL CONTINUE TO BE A CONCERN IN A SATURATED COLUMN. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY...BIG CHANGES TO THE UPPER PATTERN DURING THE EXTENDED...BUT LITTLE SENSIBLE WEATHER DIFFERENCES TO BE EXPERIENCED ACROSS THE EASTERN CAROLINAS. 600DM RIDGE AT 5H EXPANDS ACROSS THE SW...CENTERED OVER THE 4-CORNERS REGION...FORCING A DEEPENING EASTERN CONUS TROUGH. LONGWAVE PATTERN BECOMES INCREASINGLY AMPLIFIED...WITH THE EASTERN TROUGH BOOKENDED BY LARGE RIDGES BOTH UPSTREAM AND DOWNSTREAM. THIS CAUSES THE LONGITUDINAL FLOW TO COME TO A SLOW/HALT...AND THE EASTERN TROUGH WILL PERSIST THROUGH THE EXTENDED. HOWEVER...WITH TROUGH AXIS REMAINING WELL WEST OF THE AREA...DEEP SW FLOW WILL ADVECT TREMENDOUS MOISTURE AGAIN INTO THE COLUMN...EVEN AS BERMUDA HIGH SLOWLY BREAKS DOWN. THIS SUPPORTS THE POTENTIAL FOR A VERY WET PERIOD RETURNING TO THE CAROLINAS...AND SAT-MON COULD BE EVEN WETTER THAN THE PAST FEW DAYS HAVE BEEN. WPC QPF GRAPHICS SUPPORT THIS...AS CHANNELED MOISTURE TAPS THE GULF OF MEXICO AND STREAMS RIGHT INTO THE AREA. FOR NOW WILL CONTINUE CHC POP THROUGH THE PERIOD WITH HIGHS RIGHT AROUND CLIMO AND LOWS JUST A BIT ABOVE. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...SOME LIGHT CONVECTION HAS POPPED UP IN BRUNSWICK COUNTY...SOME SORT OF A WEAK CONVERGENCE BOUNDARY. THE LFC IS A BIT HIGHER TODAY...NEVERTHELESS SOME SHOWERS MAY AFFECT ILM FOR THE FIRST HOUR OR TWO. LOOK FOR SOME INTERMITTENT IFR CEILINGS AT FLO FOR THE FIRST HOUR...THEN LIFTING TO MVFR OR SCATTERING. LATER TODAY...EXPECT ACTIVITY ALONG THE SEA BREEZE BOUNDARY...WITH ISOLATED CONVECTION INLAND LATER THIS AFTERNOON. MOST OF THE CONVECTION WILL END BY 22Z...WITH MORE MID AND HIGH CLOUDS OVERNIGHT. EXTENDED OUTLOOK...ISO/SCT AFTERNOON SHOWERS AND T-STORMS THROUGH SATURDAY WITH LOCALIZED PERIODS OF MVFR/IFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 615 AM TUESDAY...WEAK RIDGING SFC AND ALOFT WILL CONTINUE ITS HOLD ACROSS THE AREA WATERS THIS NEAR TERM PERIOD. THE SFC RIDGE AXIS EXTENDING FROM THE WESTERN ATLANTIC HIGH IS PROGGED TO DROP SOUTH OF THE ILM WATERS PRIOR AS IT EXTENDS INLAND. THIS WILL RESULT IN A SW WIND DIRECTION BECOMING DOMINANT THROUGHOUT THE AREA WATERS DURING THIS TIME PERIOD. IN ADDITION...THE PIEDMONT TROF ACROSS THE CENTRAL CAROLINAS WILL BEGIN TO MATERIALIZE BY LATE IN THIS PERIOD. THE SFC PG WILL REMAIN SOMEWHAT ON THE LOOSE SIDE THIS...AND SHOULD SUPPORT 10 TO POSSIBLY 15 KT WIND SPEEDS. THE HIER SPEEDS WILL BE AIDED BY THE SEA BREEZE CIRCULATION NEAR SHORE. SIGNIFICANT SEAS WILL RUN AROUND 3 FEET...WITH FLUCTUATIONS BETWEEN 2 AND 4 FT. THE ESE-SE GROUND SWELL AT 7 TO 9 SECOND PERIODS WILL DOMINATE THE SIGNIFICANT SEAS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...BERMUDA HIGH PRESSURE REMAINS ANCHORED OFFSHORE THROUGH THE PERIOD CONTINUING SW WINDS ACROSS THE WATERS. WHILE THE PATTERN IS FAIRLY STATIC...GRADIENT WILL SLOWLY TIGHTEN...ESPECIALLY THURSDAY...THANKS TO A STRENGTHENING PIEDMONT TROUGH AND SLOWLY APPROACHING COLD FRONT. THIS CAUSES SW WINDS TO INCREASE FROM 10-15 KTS ON WEDNESDAY...TO 15-20 KTS DURING THURSDAY. WHILE A RESIDUAL 8 SEC SE SWELL WILL PERSIST IN THE WAVE SPECTRUM...SEAS WILL BECOME INCREASINGLY WIND-WAVE DOMINATED THANKS TO THE INCREASING WINDS. SIGNIFICANT WAVE AMPLITUDES WILL GROW FROM 2-4 FT WEDNESDAY...TO 3-5 FT THURSDAY...AND A FEW 6 FTERS MAY DEVELOP BY THE END OF THE PERIOD...AND WILL NEED TO MONITOR THIS FOR A POTENTIAL SCA BEGINNING LATE THURSDAY NIGHT. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 300 AM TUESDAY...HIGH PRESSURE ANCHORED WELL OFFSHORE AND COLD FRONT STALLED WELL INLAND FROM THE COAST...WILL KEEP A CONTINUOUSLY TIGHTENING PRESSURE GRADIENT OVER THE WATERS. THIS HELPS SW WINDS RISE TO AROUND 20 KTS BOTH DAYS...AND SEAS BUILD IN RESPONSE TO THESE GUSTY WINDS. WAVE HEIGHTS WILL BE 4-7 FT THROUGH THE PERIOD...AND AN EXTENDED SMALL CRAFT ADVISORY IS POSSIBLE FOR ALL LOCAL WATERS. && .TIDES/COASTAL FLOODING... AS OF 615 AM TUESDAY...THE HIGH TIDE CYCLE LATE TONIGHT WILL AGAIN BREACH THE 5.5 FT MLLW SHALLOW COASTAL FLOOD THRESHOLD...AS MEASURED BY THE ILM TIDE GAGE ALONG THE CAPE FEAR RIVER OF DOWNTOWN WILMINGTON. THE WINDOW FOR THE COASTAL FLOOD THREAT WILL RUN BETWEEN MIDNIGHT AND 2 AM WEDNESDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...JDW AVIATION...DL TIDES/COASTAL FLOODING...DCH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
626 AM EDT TUE JUN 25 2013 .SYNOPSIS... BERMUDA HIGH PRESSURE CENTERED WELL OFFSHORE WILL REMAIN IN PLACE INTO THE WEEKEND...WHILE WEAK UPPER IMPULSES TRACK JUST NORTH OF THE AREA. THIS WILL CONTINUE THE WARM AND HUMID CONDITIONS ACROSS THE AREA...WITH GOOD CHANCES FOR SHOWERS AND THUNDERSTORMS EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 615 AM TUESDAY...MODELS INDICATE RATHER LOW AMPLITUDE IE. FLAT MID AND UPPER LEVEL RIDGING EXTENDING NW ACROSS THE AREA FROM THE BASE OR CENTER LOCATED OVER THE OFFSHORE WATERS OFF THE SE U.S. COAST. MODELS INDICATE WEAK MID-LEVEL TROFFINESS ACROSS THE SE STATES WHICH WILL LIKELY BE ENOUGH TO AID IN FIRING DIURNALLY DRIVEN CONVECTION. THE SEA BREEZE AND OUTFLOWS WILL BE THE OTHER AIDS TO KEEP CONVECTION FIRING THROUGHOUT THE DAY AND INTO THE EVENING. LATEST HRRR DOES INDICATE CONVECTION TO FIRE AROUND SUNRISE BUT NOT BOUGHT ON ITS WIDESPREAD COVERAGE THAT EARLY. THINKING IS SOMEWHAT SIMILAR TO MONDAY CONCERNING POPS IN THE 30-50 PERCENT RANGE BY MID MORNING AND LASTING THROUGH MID- EVENING. NAMBUFR SOUNDINGS INDICATE 1.75 TO 2.00 PRECIPITABLE WATERS ACROSS THE FA ONCE AGAIN. THEREFORE...THE MAIN THREAT FROM TODAYS CONVECTION WILL BE THE HEAVY DOWNPOURS ACROSS GROUNDS THAT HAVE BECOME SOMEWHAT SATURATED FROM THE RECENT RAINS OF THE PAST FEW DAYS. WILL ONCE AGAIN HAVE A LOW DIURNAL RANGE BETWEEN MAX AND MIN TEMPS DUE TO CLOUDS AND THE PCPN THREAT. STAYED ON THE LOWER SIDE OF MODEL MOS GUIDANCE FOR TODAYS MAXES...AND THE HIGHER SIDE OF MODEL MOS FOR TONIGHTS LOWS. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...PERSISTENCE THE RULE FOR THE SHORT TERM AS SUMMERTIME PATTERN REMAINS IN PLACE WITH BERMUDA HIGH OFFSHORE AND FLAT RIDGING CONTINUING ALOFT. THIS CREATES A WARM...HUMID...AND ACTIVE PATTERN AS TEMPS RISE INTO THE LOW 90S AWAY FROM THE COAST...WITH LOWS FALLING ONLY INTO THE LOW 70S. HOWEVER...THERE WILL LIKELY BE CONSIDERABLE VARIABILITY EACH DAY AS CONVECTION LOOKS TO BE SCATTERED-TO-WIDESPREAD ACROSS THE AREA. IN ADDITION TO THE FLAT 5H RIDGING WHICH SLOWLY BEGINS TO BREAK DOWN...A WEAK VORT WILL CROSS OVERHEAD ON WEDNESDAY. TIMING THIS FEATURE IS STILL UNCERTAIN...AND THERE WILL BE A RACE BETWEEN SUBSIDENCE BEHIND THE VORT...AND AFTN INSTABILITY. ASSUMING THE VORT MOVES OFFSHORE EARLY...WILL CAP POP AT LOW-CHC...AND WEDNESDAY MAY BE THE DRIEST DAY OF THE WEEK. BY THURSDAY...MID LEVEL LAPSE RATES STEEPEN CONSIDERABLY AND MORE WIDESPREAD CONVECTION IS ANTICIPATED IN A CONTINUED HIGHLY UNSTABLE ENVIRONMENT. WHILE SEVERE CONVECTION LOOKS UNLIKELY...OR ISOLATED AT WORST...HEAVY RAIN AND FLOODING WILL CONTINUE TO BE A CONCERN IN A SATURATED COLUMN. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY...BIG CHANGES TO THE UPPER PATTERN DURING THE EXTENDED...BUT LITTLE SENSIBLE WEATHER DIFFERENCES TO BE EXPERIENCED ACROSS THE EASTERN CAROLINAS. 600DM RIDGE AT 5H EXPANDS ACROSS THE SW...CENTERED OVER THE 4-CORNERS REGION...FORCING A DEEPENING EASTERN CONUS TROUGH. LONGWAVE PATTERN BECOMES INCREASINGLY AMPLIFIED...WITH THE EASTERN TROUGH BOOKENDED BY LARGE RIDGES BOTH UPSTREAM AND DOWNSTREAM. THIS CAUSES THE LONGITUDINAL FLOW TO COME TO A SLOW/HALT...AND THE EASTERN TROUGH WILL PERSIST THROUGH THE EXTENDED. HOWEVER...WITH TROUGH AXIS REMAINING WELL WEST OF THE AREA...DEEP SW FLOW WILL ADVECT TREMENDOUS MOISTURE AGAIN INTO THE COLUMN...EVEN AS BERMUDA HIGH SLOWLY BREAKS DOWN. THIS SUPPORTS THE POTENTIAL FOR A VERY WET PERIOD RETURNING TO THE CAROLINAS...AND SAT-MON COULD BE EVEN WETTER THAN THE PAST FEW DAYS HAVE BEEN. WPC QPF GRAPHICS SUPPORT THIS...AS CHANNELED MOISTURE TAPS THE GULF OF MEXICO AND STREAMS RIGHT INTO THE AREA. FOR NOW WILL CONTINUE CHC POP THROUGH THE PERIOD WITH HIGHS RIGHT AROUND CLIMO AND LOWS JUST A BIT ABOVE. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...FOG/LOW STRATUS WILL LIKELY PLAGUE THE TERMINALS AGAIN EARLY THIS MORNING WITH THIS HUMID AIR MASS REMAINING ACROSS THE REGION. POCKETS OF MVFR VSBYS ARE POSSIBLE...WITH MAINLY IFR CIGS INLAND...BELOW 1K FEET...AND MVFR CIGS ALONG THE COAST. CANNOT RULE OUT TEMPO IFR FOR THE COASTAL SITES...BUT CONFIDENCE IS HIGHER FOR IFR CIGS AT KLBT/KFLO. SHRA/TSRA LIKELY WILL DEVELOP NEAR THE COAST IN THE MORNING BEFORE SHRA/TSRA SHIFTS INLAND DURING THE AFTN...WITH THE SEA BREEZE AND OUTFLOW BOUNDARIES BEING THE PRIMARY LIFTING MECHANISMS. TEMPO MVFR/IFR WILL OCCUR IN HEAVY DOWNPOURS...BUT PREVAILING VFR IS EXPECTED DURING THE DAY. RIDGING ACROSS THE AREA FROM THE WESTERN ATLANTIC HIGH WILL PRODUCE S/SW WINDS AROUND 5 KTS INLAND TERMINALS...AROUND 10 KT...EXCEPT UP TO 15 KT ACROSS THE COASTAL TERMS DURING THE HEIGHT OF THE SEA BREEZE CIRCULATION LATER TODAY. EXTENDED OUTLOOK...ISO/SCT AFTERNOON SHOWERS AND T-STORMS THROUGH SATURDAY WITH LOCALIZED PERIODS OF MVFR/IFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 615 AM TUESDAY...WEAK RIDGING SFC AND ALOFT WILL CONTINUE ITS HOLD ACROSS THE AREA WATERS THIS NEAR TERM PERIOD. THE SFC RIDGE AXIS EXTENDING FROM THE WESTERN ATLANTIC HIGH IS PROGGED TO DROP SOUTH OF THE ILM WATERS PRIOR AS IT EXTENDS INLAND. THIS WILL RESULT IN A SW WIND DIRECTION BECOMING DOMINANT THROUGHOUT THE AREA WATERS DURING THIS TIME PERIOD. IN ADDITION...THE PIEDMONT TROF ACROSS THE CENTRAL CAROLINAS WILL BEGIN TO MATERIALIZE BY LATE IN THIS PERIOD. THE SFC PG WILL REMAIN SOMEWHAT ON THE LOOSE SIDE THIS...AND SHOULD SUPPORT 10 TO POSSIBLY 15 KT WIND SPEEDS. THE HIER SPEEDS WILL BE AIDED BY THE SEA BREEZE CIRCULATION NEAR SHORE. SIGNIFICANT SEAS WILL RUN AROUND 3 FEET...WITH FLUCTUATIONS BETWEEN 2 AND 4 FT. THE ESE-SE GROUND SWELL AT 7 TO 9 SECOND PERIODS WILL DOMINATE THE SIGNIFICANT SEAS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...BERMUDA HIGH PRESSURE REMAINS ANCHORED OFFSHORE THROUGH THE PERIOD CONTINUING SW WINDS ACROSS THE WATERS. WHILE THE PATTERN IS FAIRLY STATIC...GRADIENT WILL SLOWLY TIGHTEN...ESPECIALLY THURSDAY...THANKS TO A STRENGTHENING PIEDMONT TROUGH AND SLOWLY APPROACHING COLD FRONT. THIS CAUSES SW WINDS TO INCREASE FROM 10-15 KTS ON WEDNESDAY...TO 15-20 KTS DURING THURSDAY. WHILE A RESIDUAL 8 SEC SE SWELL WILL PERSIST IN THE WAVE SPECTRUM...SEAS WILL BECOME INCREASINGLY WIND-WAVE DOMINATED THANKS TO THE INCREASING WINDS. SIGNIFICANT WAVE AMPLITUDES WILL GROW FROM 2-4 FT WEDNESDAY...TO 3-5 FT THURSDAY...AND A FEW 6 FTERS MAY DEVELOP BY THE END OF THE PERIOD...AND WILL NEED TO MONITOR THIS FOR A POTENTIAL SCA BEGINNING LATE THURSDAY NIGHT. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 300 AM TUESDAY...HIGH PRESSURE ANCHORED WELL OFFSHORE AND COLD FRONT STALLED WELL INLAND FROM THE COAST...WILL KEEP A CONTINUOUSLY TIGHTENING PRESSURE GRADIENT OVER THE WATERS. THIS HELPS SW WINDS RISE TO AROUND 20 KTS BOTH DAYS...AND SEAS BUILD IN RESPONSE TO THESE GUSTY WINDS. WAVE HEIGHTS WILL BE 4-7 FT THROUGH THE PERIOD...AND AN EXTENDED SMALL CRAFT ADVISORY IS POSSIBLE FOR ALL LOCAL WATERS. && .TIDES/COASTAL FLOODING... AS OF 615 AM TUESDAY...THE HIGH TIDE CYCLE LATE TONIGHT WILL AGAIN BREACH THE 5.5 FT MLLW SHALLOW COASTAL FLOOD THRESHOLD...AS MEASURED BY THE ILM TIDE GAGE ALONG THE CAPE FEAR RIVER OF DOWNTOWN WILMINGTON. THE WINDOW FOR THE COASTAL FLOOD THREAT WILL RUN BETWEEN MIDNIGHT AND 2 AM WEDNESDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...JDW AVIATION...DL TIDES/COASTAL FLOODING...DCH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1014 AM EDT TUE JUN 25 2013 .SYNOPSIS... DISTURBANCES EMBEDDED IN WESTERLY FLOW ALOFT WILL INTERACT WITH A WARM AND UNSTABLE AIRMASS TO PROVIDE CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS THE OHIO VALLEY THROUGH MID WEEK. THE GREATEST PRECIPITATION CHANCES WILL BE ON WEDNESDAY NIGHT...AS A COLD FRONT APPROACHES THE REGION. SLIGHTLY DRIER AND SLIGHTLY COOLER CONDITIONS ARE EXPECTED BY THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UNCERTAINTY CONTINUES IN REGARDS TO CONVECTIVE DEVELOPMENT THROUGH THE DAY. CLOUDS THINNING OUT THIS MORNING WILL RESULT IN ABUNDANT HEATING AND DESTABILIZATION. IT STILL APPEARS THAT STORMS WILL BE MOST ACTIVE IN A CORRIDOR EXTENDING FROM NORTHERN ILLINOIS INTO NORTHERN OHIO WHICH IS ALSO WHERE BETTER SHEAR IS FORECAST TO REMAIN. THESE STORMS COULD IMPACT THE FAR NORTHERN COUNTIES OF THE FORECAST AREA IN THE AFTERNOON AND HAVE MAINTAINED HIGHER CHANCE POPS THERE. ELSEWHERE STORM INITIATION IS MORE UNCERTAIN. PAST FEW RUNS OF THE HRRR AND RAP SUGGEST THAT ACTIVITY MAY NOT BE VERY EXTENSIVE NOR ORGANIZED. WITH FORCING VERY SUBTLE HAVE OPTED TO JUST BROAD BRUSH LOW END CHANCE POPS FOR NOW. FORECAST HIGHS LOOK REASONABLE AT THIS POINT. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... THE PRIMARY FOCUS FOR THE SHORT TERM WILL BE ON CONVECTION AHEAD OF A SHORTWAVE AND COLD FRONT ON WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT. WEAK RIDGING OVER THE ILN CWA TONIGHT WILL BE UNLIKELY TO FAVOR NOCTURNAL CONVECTIVE DEVELOPMENT...WITH LLJ FORCING SETTING UP TO THE WEST. THOUGH A FEW CONVECTIVE ALLOWING MODELS DO SHOW UPSTREAM CONVECTION COMING INTO THE CWA (WHICH DOES SEEM REASONABLE GIVEN LINGERING INSTABILITY)...POPS WILL BE KEPT SOMEWHAT LOW DURING THE DIURNAL MIN (30 NW / 20 SE). ON WEDNESDAY...SOUTHWESTERLY FLOW OVER THE ILN CWA WILL INCREASE...AS MOISTURE TRANSPORT BEGINS TO RAMP UP JUST WEST OF THE CWA. A SHORTWAVE AND ASSOCIATED SURFACE LOW WILL BE MOVING ACROSS THE SOUTHERN GREAT LAKES. THE FORCING AHEAD OF THE SHORTWAVE SEEMS TO BE A BIT AHEAD OF THE ILL-DEFINED COLD FRONT TRAILING THE SURFACE LOW (WHICH WILL NOT LIKELY CROSS THE CWA UNTIL THURSDAY MORNING). THE OVERALL MODEL TREND SEEMS TO ALLOW FOR A SLIGHTLY QUICKER PASSAGE OF THE SHORTWAVE (WEDNESDAY AFTERNOON INTO WEDNESDAY OVERNIGHT) THAN IN PREVIOUS FORECASTS. WITH THIS FORECAST INCORPORATING THE PRESENCE (FINALLY) OF SOME WELL-DEFINED FORCING...AND EXPECTED UNSTABLE CONDITIONS (1500-2000 J/KG...PERHAPS UP TO 3000 J/KG IF UNINHIBITED BY CLOUDS OR PRECIPITATION DURING THE DAY)...LIKELY POPS HAVE BEEN INCLUDED FOR THE ENTIRE CWA. OF GREATER CONCERN IS THE INCREASING DYNAMICS WITH THE SYSTEM...AS WNW FLOW ALOFT COMBINES WITH A STRENGTHENING BAND OF LOW-LEVEL SOUTHWESTERLY FLOW TO CREATE A SHEARED ENVIRONMENT FAVORABLE FOR STORM ORGANIZATION. TOUGH TO RULE OUT ANY PARTICULAR TYPES OR MODES OF SEVERE WEATHER AT THIS POINT...AS THERE DOES APPEAR TO BE POTENTIAL FOR QUITE A BIT MORE THAN JUST THE RUN-OF-THE-MILL STRONG TO MARGINALLY SEVERE CONVECTION OF THE PAST FEW DAYS. THE HWO WORDING WILL BE REFINED A BIT FOR THIS THREAT...WHICH MAY CONTINUE INTO THE OVERNIGHT HOURS WEDNESDAY NIGHT. SEEING SOME HYDRO PARAMETERS LIGHT UP A BIT AS WELL (PWAT WELL OVER 1.50" AND GOOD MOISTURE TRANSPORT AHEAD OF THE SHORTWAVE). THOUGH STORM ELEMENTS SHOULD BE SOMEWHAT PROGRESSIVE...SOME HEAVY RAIN WILL BE POSSIBLE. ANOTHER SHORTWAVE WILL IMPACT THE ILN CWA THURSDAY...THOUGH THE FORCING AHEAD OF THE MEAN TROUGH WILL GENERALLY BE EAST OF THE CWA. COOLING TEMPS ALOFT WILL HELP PROVIDE SOME INSTABILITY...SO CONVECTIVE CHANCES AGAIN EXIST THURSDAY (HIGHEST IN THE EASTERN CWA). IN THE WNW FLOW...PROBABLY NOT SAFE TO RULE OUT ADDITIONAL DEVELOPMENT FRIDAY...THOUGH NO STRONG SIGNALS FOR ORGANIZATION ARE PRESENT. TEMPS WILL BEGIN TO DROP SLIGHTLY AFTER THE FRONTAL PASSAGE THURSDAY MORNING. THE WARMEST DAY WILL BE WEDNESDAY...WITH MAX TEMPS AROUND 90 (A SOMEWHAT UNCERTAIN FORECAST GIVEN THE POSSIBILITY OF CLOUDS AND CONVECTION)...AND DEWPOINTS GETTING TO AROUND 70 OR EVEN THE LOWER 70S. HEAT INDICES WEDNESDAY SHOULD MAKE IT TO THE MID 90S...SHY OF ADVISORY CRITERIA BY SEVERAL DEGREES. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... BUILDING RIDGE OVER THE WESTERN UNITED STATES WILL CONTINUE TO CARVE OUT A TROUGH ACROSS THE EAST THROUGH THE REMAINDER OF THE LONG TERM PERIOD. THIS WILL KEEP TEMPERATURES FAIRLY SEASONABLE FRIDAY THROUGH MONDAY WITH HIGHS GENERALLY IN THE LOWER 80S. MODELS ARE SHOWING VARIOUS WEAK SHORT WAVES PROGRESSING THROUGH THE TROUGH BUT IT IS TOUGH TO PINPOINT ANY KIND OF TIMING. AS A RESULT...WITH THE UPPER LEVEL TROUGH IN PLACE AND GIVEN THE TIME OF YEAR...THINK THE BEST WAY TO GO IS TO TREND THE POPS DIURNAL BUT KEEP THEM ON THE LOW SIDE THROUGH THE WEEKEND. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... UPPER LEVEL FLOW WILL REMAIN ZONAL THROUGH THE TAF PERIOD. EMBEDDED DISTURBANCES WITHIN THIS FLOW WILL CONTINUE TO INTERACT WITH A MOIST AND UNSTABLE AIRMASS TO BRING A THREAT FOR SHOWERS AND THUNDERSTORMS. MODELS SUGGEST THAT AT LEAST SCATTERED CONVECTION WILL DEVELOP THIS AFTERNOON AND WILL LIKELY LINGER INTO THIS EVENING. GIVEN VARYING STORM EVOLUTION AND COVERAGE IN THE MODELS...HAVE BROAD BRUSHED THE TAFS WITH VCTS/CB UNTIL SIGNALS BECOME A LITTLE MORE CLEARER. STORMS WILL BE CAPABLE OF CONTAINING BRIEF HEAVY RAIN WITH MVFR CIGS AND IFR VSBYS. FOR TONIGHT...PREVIOUS THINKING WAS THE PERHAPS CONVECTION WOULD SHIFT SOMEWHAT TO THE NORTH AND STAY FOCUSED MORE ACROSS THE SRN GREAT LAKES. SOME LATER MODEL RUNS SUGGEST THAT PERHAPS CONVECTION MAY NOW SEEP SOUTH INTO THE REGION...ESPECIALLY NEAR THE NORTHERN TAF SITES. GIVEN LOW CONFIDENCE...HAVE KEPT THE TAFS DRY FOR NOW. OUTLOOK...THUNDERSTORMS EXPECTED FROM WEDNESDAY AFTERNOON THROUGH THURSDAY. THUNDERSTORMS POSSIBLE...MAINLY AFTERNOON AND EVENING...FRIDAY AND SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM... SHORT TERM...HATZOS LONG TERM...JGL AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS SPOKANE WA
434 AM PDT Tue Jun 25 2013 .SYNOPSIS... A wet pattern will continue across the Inland Northwest through mid week...with frequent showers and the potential for thunderstorms. The weather the second half of the week will be dramatically different as a warming and drying trend quickly develops by late week. Summer-like temperatures will be likely as we move towards the end of the week. && .DISCUSSION... Today and tonight...Little if any change to the longwave pattern consisting of large longwave trof offshore up against inland ridging which continues to funnel through negatively tilted disturbances tied into moderate and effective sources of moisture. The end result is another fairly wet forecast for today that shows some improvement after 11 pm tonight but still not yet enough to dry it out totally as per the latest GFS with a number of this morning`s HRRR model runs support this solution. Otherwise with such abundant moisture lingering from past and present rainfall some low clouds and fog may get mentioned at times in the mix. Minor change was removal of thunderstorm mention near the cascades as lapse rates don`t appear to be steep enough to support it there but have left minor mention for afternoon and evening further east closer to Spokane and vicinity and the North Idaho Panhandle. /Pelatti Wed through Sat morning: Following what should be our last day of meaningful chances of pcpn on Wed into Wed Nt will be a rapid warming and drying trend beginning Thurs. This pcpn chance Wed should not be too widespread, but certainly heaviest during the afternoon and evening as the region remains under a long-fetch moisture plume drifting north. This pcpn threat will last into Thurs morning. Though not currently in the fcst, there could be an isolated threat of thunder Wed afternoon across NE Wa as well as near the Camas Prairie and Nrn Blue Mtns of Wa. One note of interest concerning pcpn chances Fri Nt: The GFS advects of plume of elevated instability above about 700mb north through Oregon and into SE Wa Fri Nt. The RH in this layer a rather dry, and the GFs is the only model guidance that produces nocturnal pcpn (very light and spotty). We did not put any of this pcpn in the fcst, but it`s something to watch. 500mb ht rises close of 150-200m, accompanying 850mb temp rises around 10c, will push hi temps nearly 10F above normal by Fri. bz Saturday through Tuesday...An upper level ridge will amplify dramatically over the Inland Northwest through early next week, with the result being the hottest temperatures we`ve seen so far this early summer season (it`s still very early). All the gnashing of teeth regarding the recent rainfall and cool temperatures will stop as temperatures will warm well into the 80s and 90s, with isolated locations approaching the century mark. The extended models produce high temperatures that are 15+ above normal. Had it not been for the recent soaking rainfalls the hot temperatures may not be as hard to realize. But since many areas have received their June`s average total rainfall over the last week, afternoon temperatures should remain below the hottest of the guidance numbers. At least through the weekend. If the ridge continues to amplify next week, enough drying at the surface would allow for even higher temperatures. ty && .AVIATION... 12Z TAFS: A moist and slightly unstable flow from the southwest will continue to steer small scale disturbances over the aviation area today and into the evening. MVFR ceilings and visibilities mostly due to low level clouds and fog associated with the abundant low level moisture left due to yesterdays and todays rainfall. Otherwise some low MVFR ceilings may be associated with the showers and/or thunderstorms. /Pelatti && .PRELIMINARY POINT TEMPS/POPS... Spokane 65 52 73 54 79 57 / 90 50 30 10 0 0 Coeur d`Alene 65 52 72 53 79 54 / 90 50 30 10 0 0 Pullman 65 53 73 54 81 53 / 80 50 40 10 0 0 Lewiston 73 57 81 58 89 60 / 80 60 40 20 0 0 Colville 69 52 74 53 82 53 / 90 60 40 20 0 0 Sandpoint 66 51 71 52 77 50 / 90 60 40 20 0 0 Kellogg 63 50 69 52 77 56 / 90 60 30 20 0 0 Moses Lake 70 57 78 58 86 59 / 70 20 10 10 0 0 Wenatchee 70 55 77 60 84 63 / 80 20 20 10 0 0 Omak 70 53 76 54 82 57 / 80 30 20 10 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS TAUNTON MA
447 PM EDT TUE JUN 25 2013 .SYNOPSIS... WARM AND MUGGY CONDITIONS WILL CONTINUE AS SHOWERS AND THUNDERSTORMS BECOME MORE WIDESPREAD INTO THE END OF THE WEEK. WHILE HEAVY RAIN WITH POTENTIAL LOCALIZED FLOODING IS THE PRIMARY THREAT...STRONG THUNDERSTORMS WILL BE POSSIBLE AS A COLD FRONT SLOWLY APPROACHES FROM THE WEST THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 10 PM THIS EVENING/... *** HEAT AND HUMIDITY CONTINUE INTO TODAY *** *** THUNDERSTORMS WITH HEAVY DOWNPOURS POSSIBLE *** 2 PM UPDATE...TEMPERATURES ARE IN THE UPPER 80S AND LOWER 90S ACROSS MUCH OF THE AREA...WITH MID 80S EVEN ON THE OUTER CAPE AND MARTHAS VINEYARD. WHILE TEMPERATURES ARE DEFINITELY HOT...WE ARE NOT IN DANGER OF HITTING THE RECORDS TODAY. BOTH BOSTON AND HARTFORD HAVE HIT 90 DEGREES FOR THE THIRD DAY IN A ROW MAKING IT AN OFFICIAL HEAT WAVE AT THOSE TWO SITES. OUR TWO OTHER OFFICIAL CLIMATE STATIONS...WORCESTER AND PROVIDENCE...HAVE NOT YET HAD A HEAT WAVE. WORCESTER HAS NOT HAD ANY HIGH TEMPERATURES OVER 90 DEGREES AND PROVIDENCE HAS HIT 90 DEGREES FOR ONLY THE SECOND DAY IN A ROW. THE CONVECTIVE TEMPERATURE ACROSS THE AREA IS ALSO IN THE UPPER 80S TO LOWER 90S SO SHOWERS AND THUNDERSTORMS ARE LIKELY TO DEVELOP AS WE GO THROUGH THE AFTERNOON. STORMS HAVE ALREADY POPPED ACROSS MUCH OF NEW YORK STATE AND PORTIONS OF NORTHERN NEW ENGLAND. SPC MESOANALYSIS HAS UP TO 3000 J/KG OF SB CAPE ACROSS MUCH OF THE AREA WITH LITTLE TO NO CONVECTIVE INHIBITION. LIKE YESTERDAY... THERE IS VERY LITTLE SHEAR. BETWEEN THIS AND A LACK OF A GOOD TRIGGER LIKE A SHORTWAVE OR A FRONT...EXPECT THE THREATS FROM THESE STORMS TO MAINLY BE HEAVY RAIN AND FREQUENT LIGHTNING. PRECIPITABLE WATER VALUES ARE FORECAST TO INCREASE TO BETWEEN 1.5 AND 2 INCHES WHICH IS 2 TIMES THE NORMAL. THERE IS A LOW PROBABILITY OF STRONG WIND GUSTS TO 50 MPH AND PEA SIZE HAIL WITH ANY OF THESE STORMS. THE HRRR MODEL STILL SHOWS A CONVECTIVE LINE MOVING THROUGH SOUTHERN NEW ENGLAND BETWEEN 21-01Z. FROM JUST THE INSTABILITY AND SHEAR AVAILABLE...WOULD HAVE LOW CONFIDENCE ON THIS LINE DEVELOPING. HOWEVER...THE HRRR IS DOING A GREAT JOB WITH THE CONVECTION ACROSS NEW YORK STATE SO TEND TO HAVE A BIT MORE CONFIDENCE IN THAT MODELS SOLUTION. HIGHEST CONFIDENCE IS ACROSS NORTHERN MASSACHUSETTS AND SOUTHERN NEW HAMPSHIRE CLOSER TO A WEAK SHORTWAVE MOVING THROUGH QUEBEC. && .SHORT TERM /10 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... TONIGHT...ANY LINGERING SHOWERS AND THUNDERSTORMS WILL DIMINISH LATE TONIGHT. WILL BE ANOTHER WARM AND MUGGY NIGHT WITH LOW TEMPERATURES IN THE UPPER 60S TO THE LOWER 70S. FOG IS A POSSIBILITY AGAIN TONIGHT WITH THE BEST CHANCE ACROSS THE SOUTH COAST...CAPE...AND ISLANDS. WEDNESDAY...SHOWERS AND THUNDERSTORMS ARE LIKELY ONCE AGAIN. THERE IS ACTUALLY A BETTER CHANCE WEDNESDAY THAN TODAY WITH A SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND INCREASING SHEAR AND PROVIDING A TRIGGER. THE HEAT AND HUMIDITY SHOULD CONTINUE WHICH WILL KEEP CAPE VALUES HIGH. SO WITH PLENTY OF INSTABILITY...25 TO 30 KTS OF SHEAR AND PLENTY OF MOISTURE WITH PWATS UP TO 2 INCHES...EXPECT THUNDERSTORMS WITH HEAVY RAIN AND STRONG TO DAMAGING WINDS. TEMPERATURES WILL BE A BIT COOLER...PARTICULARLY ACROSS THE NORTHERN ZONES WHERE A BACK DOOR COLD FRONT MAY TRY TO EDGE IN. EXPECT HIGHEST TEMPERATURES IN THE UPPER 80S TO LOW 90S ALONG AND SOUTH OF THE MASS PIKE AND SLIGHTLY COOLER TEMPERATURES NORTH OF THE MASS PIKE WITH HIGHS IN THE MID 80S. WEDNESDAY NIGHT...COOLER TEMPERATURE TREND WILL CONTINUE WITH THE BACK DOOR FRONT CONTINUING TO MOVE SOUTHWARD THROUGH SOUTHERN NEW ENGLAND. EXPECT OVERNIGHT LOWS IN THE MID TO UPPER 60S. ANY CONVECTION DURING THE DAY WILL LIKELY CONTINUE FOR MUCH OF THE NIGHT WITH LIFT PROVIDED BY THE SHORTWAVE AND THE BACK DOOR FRONT. HEAVY RAIN AND ANY URBAN AND POOR DRAINAGE FLOODING WILL BE THE MAIN CONCERNS OVERNIGHT...THOUGH STRONG GUSTY WINDS AND SMALL HAIL CANNOT BE RULED OUT. ONCE AGAIN...FOG IS LIKELY...PARTICULARLY ALONG THE SOUTH COAST. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HEADLINES... * HEAVY RAIN THREAT PREVAILS THROUGH MOST OF THIS TIMEFRAME * LOCALIZED URBAN AND LOW LYING AREA FLOODING IS A POSSIBILITY * STRONG THUNDERSTORMS POSSIBLE THURSDAY * CONTINUED WARM AND MUGGY CONDITIONS OVERVIEW AND MODEL PREFERENCES... MEDIUM RANGE MODELS CONTINUE TO SIGNAL HIGHLY ANOMALOUS UPPER LEVEL BLOCKING PATTERN FOR EARLY SUMMER...WITH HIGH AMPLITUDE RIDGE ACROSS THE WESTERN U.S. AND LONG WAVE TROUGH ACROSS THE E. THIS WILL KEEP THE REGION IN A RELATIVELY UNSETTLED PATTERN THANKS TO THE UPPER TROUGH/CUTOFF LOW NEAR OR TO THE W OF THE REGION...THOUGH SOME MODELS ARE TRYING TO RETROGRADE THE TROUGH A BIT FURTHER W LATE IN THE PERIOD /MON- TUE/ TO PUSH THREAT OF SHOWERS FURTHER W. ALSO NOTING SOME BRIEF BREAKS IN THE ACTION...MAINLY AROUND THE LATE THU-FRI TIMEFRAME AS SEEN ON 12Z OP RUNS OF THE GFS/GGEM AND ECMWF. THIS IS JUST ONE RUN...THOUGH...SO NOT VERY CONFIDENT. WILL STILL SEE PROLONGED PERIOD OF WARM AND HUMID CONDITIONS. WITH HIGH PWATS...ON THE ORDER OF 1.7 TO AROUND 2 INCHES WITH PROLONGED S-SW FLOW IN PLACE...EXPECT ANY SHOWERS/TSTMS TO PRODUCE LOCALLY HEAVY RAINFALL ESPECIALLY THU AND FRI. WILL NOT SEE A COMPLETE WASHOUT...BUT MAY SEE PERIODS OF SHOWERS/TSTMS EACH DAY. BY THIS WEEKEND...COULD SEE SOME GRADUAL IMPROVEMENT BUT THIS WILL BE DEPENDENT UPON WHETHER THE TROUGH ACTUALLY RETROGRADE AS MODELS ARE SUGGESTING. LEANED TOWARD A BLEND OF THE PREVIOUS FORECAST WITH THE WPC GUIDANCE...WHICH USED A BLEND OF THE GFS/ECMWF AND THEIR ENSEMBLE MEANS. THIS GAVE GOOD CONTINUITY TO THE LAST SEVERAL FORECASTS. DETAILS... THURSDAY-FRIDAY...CONTINUED THREAT OF SHOWERS/TSTMS DURING THIS TIMEFRAME. BEST INSTABILITY WILL BE ACROSS CENTRAL AND WESTERN AREAS THU INTO FRI MORNING SO HAVE KEPT LIKELY POPS GOING THERE. WILL ALSO SEE HEAVY RAINFALL AND POSSIBLE LOCALIZED FLOODING... THOUGH TOUGH TO PINPOINT WHERE THESE WILL OCCUR. DURING THE DAY FRIDAY INTO FRIDAY NIGHT...MAY SEE LESSER OF A CHANCE OF PRECIP AS BRIEF LULL MOVES ACROSS. WITH HIGH HUMIDITIES...CAN NOT RULE OUT THE CHANCE OF PRECIP THOUGH SO LEFT LOW CHANCE POPS GOING. WILL ALSO SEE PATCHY FOG DEVELOP EACH NIGHT/EARLY MORNING TIMEFRAME ESPECIALLY ALONG THE S COAST WITH SUCH MUGGY CONDITIONS IN PLACE. MAY SEE GUSTY WINDS ALONG THE S COAST FRIDAY AS S-SW LOW LEVEL JET SETS UP. GUSTS UP TO 25-30 KT POSSIBLE. SATURDAY-TUESDAY...WILL SEE CONTINUED CHANCE POPS FOR MOST OF THIS TIMEFRAME...THOUGH MAY SEE A SLOWLY LOWER CHANCE MON-TUE IF THE MODELS VERIFY AND TRY TO RETROGRADE INSTABILITY AXIS TO THE W. KEPT MENTION OF TSTMS MAINLY DURING THE DAYLIGHT HOURS THIS WEEKEND...THEN MOVED IT W EARLY NEXT WEEK. LOW LEVEL JET IN PLACE ON SAT MAY BRING GUSTS ALONG THE S COAST UP TO 25 KT. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM THROUGH WEDNESDAY NIGHT...MODERATE CONFIDENCE. THROUGH 00Z...MAINLY VFR. AFTER 21Z...PATCHY MVFR/IFR CONDITIONS IN SCT SHRA/TSRA. TONIGHT...MAINLY VFR. SCT SHRA/TSRA CONTINUES TO MOVE EAST THROUGH 06Z RESULTING IN BRIEF MVFR/IFR CONDITIONS. MVFR/IFR STRATUS AND FOG LIKELY ALONG THE SOUTH COAST. WEDNESDAY...ANOTHER ROUND OF SHRA/TSRA IN THE AFTERNOON HOURS. GUSTY WINDS AND REDUCED VSBYS GREATEST THREATS. WEDNESDAY NIGHT...SCT SHRA/TSRA POSSIBLE DURING THE EVENING HOURS. LOW CLOUDS/FOG POSSIBLE AGAIN ALONG THE SOUTH COAST WITH MVFR/IFR CONDITIONS. KBOS TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. KBDL TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. OUTLOOK...THURSDAY THROUGH SUNDAY... THURSDAY...BEST CHANCE FOR SHRA/TSRA REMAINS ACROSS INTERIOR NEW ENGLAND. LOCAL +RA EXPECTED. GUSTY WINDS POSSIBLE...BEST CHANCE ALONG S COAST. LOW END VFR TO MVFR CIGS WITH CB ALONG WITH MVFR- IFR VSBYS POSSIBLE IN PATCHY FOG MAINLY THU NIGHT. PREVAILING S-SW WINDS. LLWS POSSIBLE THU NIGHT MAINLY ACROSS S COASTAL AREAS. FRIDAY...SHRA/TSRA REMAIN MORE WIDESPREAD ACROSS CENTRAL AND WESTERN AREAS WITH CHANCE POPS CONTINUING OVER THE EAST EARLY. MAY SEE BRIEF LULL IN ACTION LATE FRI/FRI NIGHT...THOUGH PATCHY FOG WITH MVFR-IFR VSBYS WILL CONTINUE. GUSTY S-SW WINDS POSSIBLE. LLWS POSSIBLE ACROSS S COASTAL AREAS. SATURDAY-SUNDAY...CONTINUED CHANCE FOR SHRA/TSRA OFF AND ON THROUGH THIS TIMEFRAME. GUSTY S-SW WINDS POSSIBLE. LOW END VFR TO MVFR CIGS WITH CB ALONG WITH MVFR-IFR VSBYS POSSIBLE. PREVAILING SW WINDS. LLWS POSSIBLE SAT ACROSS S COASTAL AREAS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM THROUGH WEDNESDAY NIGHT...HIGH CONFIDENCE. TODAY THROUGH WEDNESDAY NIGHT... ESSENTIALLY...EXPECTING A REPEAT OF TODAY AND LAST NIGHT. WINDS AND SEAS GENERALLY REMAIN BELOW SMALL CRAFT CRITERIA THOUGH SEAS MAY RISE TO ABOUT 5 FEET ON THE OUTER WATERS. FOG WILL DEVELOP OVERNIGHT AND THEN BURN OFF BY MIDDAY AND GIVE WAY TO LATE DAY TSTMS. MAIN THREATS HEAVY RAIN AND FREQUENT LIGHTNING. OUTLOOK...THURSDAY THROUGH SATURDAY... S-SW WINDS GUSTING UP TO 25 KT AT TIMES...MAINLY THU NIGHT THROUGH SUNDAY. LONG SOUTH TO SOUTHWEST FETCH WILL BRING SEAS UP TO 5-8 FT ACROSS THE OUTER COASTAL WATERS...POSSIBLY INTO RI AND BLOCK ISLAND SOUNDS AS WELL. SCATTERED SHOWERS/TSTMS...MAINLY DURING THE AFTERNOON/EVENING HOURS. HEAVY RAIN AND FREQUENT LIGHTNING IN ANY STORMS. PATCHY FOG WITH REDUCED VSBYS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...AIR QUALITY ALERT UNTIL 10 PM EDT THIS EVENING FOR MAZ020>024. NH...NONE. RI...AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>008. MARINE...NONE. && $$ SYNOPSIS...RLG/EVT NEAR TERM...RLG SHORT TERM...RLG LONG TERM...EVT AVIATION...RLG/EVT MARINE...RLG/EVT
AREA FORECAST DISCUSSION
NWS TAUNTON MA
304 PM EDT TUE JUN 25 2013 .SYNOPSIS... WARM AND MUGGY CONDITIONS WILL CONTINUE AS SHOWERS AND THUNDERSTORMS BECOME MORE WIDESPREAD INTO THE END OF THE WEEK. WHILE HEAVY RAIN WITH POTENTIAL LOCALIZED FLOODING IS THE PRIMARY THREAT...STRONG THUNDERSTORMS WILL BE POSSIBLE AS A COLD FRONT SLOWLY APPROACHES FROM THE WEST THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 10 PM THIS EVENING/... *** HEAT AND HUMIDITY CONTINUE INTO TODAY *** *** THUNDERSTORMS WITH HEAVY DOWNPOURS POSSIBLE *** 2 PM UPDATE...TEMPERATURES ARE IN THE UPPER 80S AND LOWER 90S ACROSS MUCH OF THE AREA...WITH MID 80S EVEN ON THE OUTER CAPE AND MARTHAS VINEYARD. WHILE TEMPERATURES ARE DEFINITELY HOT...WE ARE NOT IN DANGER OF HITTING THE RECORDS TODAY. BOTH BOSTON AND HARTFORD HAVE HIT 90 DEGREES FOR THE THIRD DAY IN A ROW MAKING IT AN OFFICIAL HEAT WAVE AT THOSE TWO SITES. OUR TWO OTHER OFFICIAL CLIMATE STATIONS...WORCESTER AND PROVIDENCE...HAVE NOT YET HAD A HEAT WAVE. WORCESTER HAS NOT HAD ANY HIGH TEMPERATURES OVER 90 DEGREES AND PROVIDENCE HAS HIT 90 DEGREES FOR ONLY THE SECOND DAY IN A ROW. THE CONVECTIVE TEMPERATURE ACROSS THE AREA IS ALSO IN THE UPPER 80S TO LOWER 90S SO SHOWERS AND THUNDERSTORMS ARE LIKELY TO DEVELOP AS WE GO THROUGH THE AFTERNOON. STORMS HAVE ALREADY POPPED ACROSS MUCH OF NEW YORK STATE AND PORTIONS OF NORTHERN NEW ENGLAND. SPC MESOANALYSIS HAS UP TO 3000 J/KG OF SB CAPE ACROSS MUCH OF THE AREA WITH LITTLE TO NO CONVECTIVE INHIBITION. LIKE YESTERDAY... THERE IS VERY LITTLE SHEAR. BETWEEN THIS AND A LACK OF A GOOD TRIGGER LIKE A SHORTWAVE OR A FRONT...EXPECT THE THREATS FROM THESE STORMS TO MAINLY BE HEAVY RAIN AND FREQUENT LIGHTNING. PRECIPITABLE WATER VALUES ARE FORECAST TO INCREASE TO BETWEEN 1.5 AND 2 INCHES WHICH IS 2 TIMES THE NORMAL. THERE IS A LOW PROBABILITY OF STRONG WIND GUSTS TO 50 MPH AND PEA SIZE HAIL WITH ANY OF THESE STORMS. THE HRRR MODEL STILL SHOWS A CONVECTIVE LINE MOVING THROUGH SOUTHERN NEW ENGLAND BETWEEN 21-01Z. FROM JUST THE INSTABILITY AND SHEAR AVAILABLE...WOULD HAVE LOW CONFIDENCE ON THIS LINE DEVELOPING. HOWEVER...THE HRRR IS DOING A GREAT JOB WITH THE CONVECTION ACROSS NEW YORK STATE SO TEND TO HAVE A BIT MORE CONFIDENCE IN THAT MODELS SOLUTION. HIGHEST CONFIDENCE IS ACROSS NORTHERN MASSACHUSETTS AND SOUTHERN NEW HAMPSHIRE CLOSER TO A WEAK SHORTWAVE MOVING THROUGH QUEBEC. && .SHORT TERM /10 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... TONIGHT...ANY LINGERING SHOWERS AND THUNDERSTORMS WILL DIMINISH LATE TONIGHT. WILL BE ANOTHER WARM AND MUGGY NIGHT WITH LOW TEMPERATURES IN THE UPPER 60S TO THE LOWER 70S. FOG IS A POSSIBILITY AGAIN TONIGHT WITH THE BEST CHANCE ACROSS THE SOUTH COAST...CAPE...AND ISLANDS. WEDNESDAY...SHOWERS AND THUNDERSTORMS ARE LIKELY ONCE AGAIN. THERE IS ACTUALLY A BETTER CHANCE WEDNESDAY THAN TODAY WITH A SHORTWAVE MOVING ACROSS SOUTHERN NEW ENGLAND INCREASING SHEAR AND PROVIDING A TRIGGER. THE HEAT AND HUMIDITY SHOULD CONTINUE WHICH WILL KEEP CAPE VALUES HIGH. SO WITH PLENTY OF INSTABILITY...25 TO 30 KTS OF SHEAR AND PLENTY OF MOISTURE WITH PWATS UP TO 2 INCHES...EXPECT THUNDERSTORMS WITH HEAVY RAIN AND STRONG TO DAMAGING WINDS. TEMPERATURES WILL BE A BIT COOLER...PARTICULARLY ACROSS THE NORTHERN ZONES WHERE A BACK DOOR COLD FRONT MAY TRY TO EDGE IN. EXPECT HIGHEST TEMPERATURES IN THE UPPER 80S TO LOW 90S ALONG AND SOUTH OF THE MASS PIKE AND SLIGHTLY COOLER TEMPERATURES NORTH OF THE MASS PIKE WITH HIGHS IN THE MID 80S. WEDNESDAY NIGHT...COOLER TEMPERATURE TREND WILL CONTINUE WITH THE BACK DOOR FRONT CONTINUING TO MOVE SOUTHWARD THROUGH SOUTHERN NEW ENGLAND. EXPECT OVERNIGHT LOWS IN THE MID TO UPPER 60S. ANY CONVECTION DURING THE DAY WILL LIKELY CONTINUE FOR MUCH OF THE NIGHT WITH LIFT PROVIDED BY THE SHORTWAVE AND THE BACK DOOR FRONT. HEAVY RAIN AND ANY URBAN AND POOR DRAINAGE FLOODING WILL BE THE MAIN CONCERNS OVERNIGHT...THOUGH STRONG GUSTY WINDS AND SMALL HAIL CANNOT BE RULED OUT. ONCE AGAIN...FOG IS LIKELY...PARTICULARLY ALONG THE SOUTH COAST. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HEADLINES... * HEAVY RAIN THREAT PREVAILS THROUGHOUT THIS TIMEFRAME * LOCALIZED URBAN AND LOW LYING AREA FLOODING IS A POSSIBILITY * STRONG THUNDERSTORMS POSSIBLE LATE THIS WEEK INTO NEXT MONDAY * CONTINUED WARM AND MUGGY CONDITIONS 25/00Z GUIDANCE CONTINUES TO EXHIBIT OVERALL AGREEMENT WITH THEIR SYNOPTIC SOLUTIONS. THERE REMAIN SOME DETAIL DIFFERENCES...WHICH WILL TAKE SOME TIME TO RESOLVE BASED ON THE NATURE OF THE EXPECTED PATTERN FOR MOST OF THIS WEEK. HAVE LOWER CONFIDENCE IN THE DETAILS OF ANY PARTICULAR SOLUTION AT THIS TIME. AS SUCH...FOLLOWED A CONSENSUS BLEND TO MINIMIZE THE DETAIL DIFFERENCES. IT APPEARS SOUTHERN NEW ENGLAND IS IN FOR A PROLONGED STRETCH OF UNSETTLED WEATHER OVER THE NEXT SEVERAL DAYS. A MID-LEVEL BLOCKING PATTERN IS EXPECTED TO ESTABLISH ITSELF ACROSS THE NORTHERN HALF OF THE CONUS...PLACING OUR REGION JUST EAST OF A MID-LEVEL TROUGH. AT THE SURFACE...THIS WOULD MAINTAIN A GENERAL SOUTHERLY FLOW INTO THIS WEEKEND ALONG WITH HIGH HUMIDITY. TEMPERATURES SHOULD GRADUALLY MODERATE AS CLOUDS BECOME MORE PREVALENT LATE THIS WEEK. AM NOT EXPECTING A COMPLETE WASHOUT...BUT FINDING IT TOUGH TO FIND A DAY WITHOUT A CHANCE OF SHOWERS OR THUNDERSTORMS AT SOME POINT. HIGH HUMIDITY WILL POSE A RISK FOR LOCALIZED HEAVY RAINFALL IN STRONGER SHOWERS AND THUNDERSTORMS INTO EARLY NEXT WEEK. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM THROUGH WEDNESDAY NIGHT...MODERATE CONFIDENCE. THROUGH 00Z...MAINLY VFR. AFTER 21Z...PATCHY MVFR/IFR CONDITIONS IN SCT SHRA/TSRA. TONIGHT...MAINLY VFR. SCT SHRA/TSRA CONTINUES TO MOVE EAST THROUGH 06Z RESULTING IN BRIEF MVFR/IFR CONDITIONS. MVFR/IFR STRATUS AND FOG LIKELY ALONG THE SOUTH COAST. WEDNESDAY...ANOTHER ROUND OF SHRA/TSRA IN THE AFTERNOON HOURS. GUSTY WINDS AND REDUCED VSBYS GREATEST THREATS. WEDNESDAY NIGHT...SCT SHRA/TSRA POSSIBLE DURING THE EVENING HOURS. LOW CLOUDS/FOG POSSIBLE AGAIN ALONG THE SOUTH COAST WITH MVFR/IFR CONDITIONS. KBOS TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. KBDL TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. OUTLOOK...THURSDAY THROUGH SATURDAY... THURSDAY...SHRA/TSRA LOOK TO REMAIN CONFINED ACROSS INTERIOR NEW ENGLAND. LOCAL +RA EXPECTED. GUSTY WINDS POSSIBLE. LOW-VFR TO MVFR CIGS WITH CB ALONG WITH MVFR-IFR VSBYS POSSIBLE. PREVAILING S-SW WINDS. LLWS POSSIBLE THU NIGHT MAINLY ACROSS S COASTAL AREAS. FRIDAY AND SATURDAY... SHRA/TSRA WILL BE MORE WIDESPREAD ACROSS MOST OF SOUTHERN NEW ENGLAND...WITH THE BEST CHANCE ACROSS CENTRAL AND WESTERN AREAS. +RA EXPECTED WITH GUSTY WINDS POSSIBLE. LOW-VFR TO MVFR CIGS WITH CB ALONG WITH MVFR-IFR VSBYS POSSIBLE. PREVAILING SW WINDS. LLWS MAY BE POSSIBLE FRI THROUGH SAT ACROSS S COASTAL AREAS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM THROUGH WEDNESDAY NIGHT...HIGH CONFIDENCE. TODAY THROUGH WEDNESDAY NIGHT... ESSENTIALLY...EXPECTING A REPEAT OF TODAY AND LAST NIGHT. WINDS AND SEAS GENERALLY REMAIN BELOW SMALL CRAFT CRITERIA THOUGH SEAS MAY RISE TO ABOUT 5 FEET ON THE OUTER WATERS. FOG WILL DEVELOP OVERNIGHT AND THEN BURN OFF BY MIDDAY AND GIVE WAY TO LATE DAY TSTMS. MAIN THREATS HEAVY RAIN AND FREQUENT LIGHTNING. OUTLOOK...THURSDAY THROUGH SATURDAY... SOUTH TO SOUTHWEST WINDS MAY GUST UP TO 25 KT AT TIMES...MAINLY FRIDAY INTO SATURDAY. LONG SOUTH TO SOUTHWEST FETCH WILL BRING SEAS UP TO 5-8 FT ACROSS THE OUTER COASTAL WATERS...POSSIBLY INTO RI AND BLOCK ISLAND SOUNDS AS WELL. SCATTERED SHOWERS/TSTMS... MAINLY DURING THE AFTERNOON/EVENING HOURS. HEAVY RAIN AND FREQUENT LIGHTNING IN ANY STORMS. PATCHY FOG WITH REDUCED VSBYS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...AIR QUALITY ALERT UNTIL 10 PM EDT THIS EVENING FOR MAZ020>024. NH...NONE. RI...AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>008. MARINE...NONE. && $$ SYNOPSIS...BELK/RLG NEAR TERM...RLG SHORT TERM...RLG LONG TERM...BELK AVIATION...BELK/RLG MARINE...BELK/RLG
AREA FORECAST DISCUSSION
NWS TAUNTON MA
154 PM EDT TUE JUN 25 2013 .SYNOPSIS... WARM AND MUGGY CONDITIONS WILL CONTINUE AS SHOWERS AND THUNDERSTORMS BECOME MORE WIDESPREAD INTO THE END OF THE WEEK. WHILE HEAVY RAIN WITH POTENTIAL LOCALIZED FLOODING IS THE PRIMARY THREAT...STRONG THUNDERSTORMS WILL BE POSSIBLE AS A COLD FRONT SLOWLY APPROACHES FROM THE WEST THIS WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... *** HEAT AND HUMIDITY CONTINUE INTO TODAY *** *** THUNDERSTORMS WITH HEAVY DOWNPOURS POSSIBLE *** 2 PM UPDATE...TEMPERATURES ARE IN THE UPPER 80S AND LOWER 90S ACROSS MUCH OF THE AREA...WITH MID 80S EVEN ON THE OUTER CAPE AND MARTHAS VINEYARD. WHILE TEMPERATURES ARE DEFINITELY HOT...WE ARE NOT IN DANGER OF HITTING THE RECORDS TODAY. BOTH BOSTON AND HARTFORD HAVE HIT 90 DEGREES FOR THE THIRD DAY IN A ROW MAKING IT AN OFFICIAL HEAT WAVE AT THOSE TWO SITES. OUR TWO OTHER OFFICIAL CLIMATE STATIONS...WORCESTER AND PROVIDENCE...HAVE NOT YET HAD A HEAT WAVE. WORCESTER HAS NOT HAD ANY HIGH TEMPERATURES OVER 90 DEGREES AND PROVIDENCE HAS HIT 90 DEGREES FOR ONLY THE SECOND DAY IN A ROW. THE CONVECTIVE TEMPERATURE ACROSS THE AREA IS ALSO IN THE UPPER 80S TO LOWER 90S SO SHOWERS AND THUNDERSTORMS ARE LIKELY TO DEVELOP AS WE GO THROUGH THE AFTERNOON. STORMS HAVE ALREADY POPPED ACROSS MUCH OF NEW YORK STATE AND PORTIONS OF NORTHERN NEW ENGLAND. SPC MESOANALYSIS HAS UP TO 3000 J/KG OF SB CAPE ACROSS MUCH OF THE AREA WITH LITTLE TO NO CONVECTIVE INHIBITION. LIKE YESTERDAY... THERE IS VERY LITTLE SHEAR. BETWEEN THIS AND A LACK OF A GOOD TRIGGER LIKE A SHORTWAVE OR A FRONT...EXPECT THE THREATS FROM THESE STORMS TO MAINLY BE HEAVY RAIN AND FREQUENT LIGHTNING. PRECIPITABLE WATER VALUES ARE FORECAST TO INCREASE TO BETWEEN 1.5 AND 2 INCHES WHICH IS 2 TIMES THE NORMAL. THERE IS A LOW PROBABILITY OF STRONG WIND GUSTS TO 50 MPH AND PEA SIZE HAIL WITH ANY OF THESE STORMS. THE HRRR MODEL STILL SHOWS A CONVECTIVE LINE MOVING THROUGH SOUTHERN NEW ENGLAND BETWEEN 21-01Z. FROM JUST THE INSTABILITY AND SHEAR AVAILABLE...WOULD HAVE LOW CONFIDENCE ON THIS LINE DEVELOPING. HOWEVER...THE HRRR IS DOING A GREAT JOB WITH THE CONVECTION ACROSS NEW YORK STATE SO TEND TO HAVE A BIT MORE CONFIDENCE IN THAT MODELS SOLUTION. HIGHEST CONFIDENCE IS ACROSS NORTHERN MASSACHUSETTS AND SOUTHERN NEW HAMPSHIRE CLOSER TO A WEAK SHORTWAVE MOVING THROUGH QUEBEC. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... TONIGHT...LINGERING CONVECTION SHOULD DWINDLE DOWN AFTER SUNSET AS DIURNAL HEATING DISSIPATES. EXPECT TEMPS TO DROP INTO THE MID TO UPPER 60S WITH LOW 70S FOR METRO PROVIDENCE AND BOSTON. CHANCES FOR FOG DEVELOPMENT WILL INCREASE AGAIN AS DEWPOINTS ARE HIGH. EXPECT MUCH OF THE REGION TO SEE SOME PATCHY FOG WITH THE CAPE/ISLANDS HAVING THE BEST CHANCE FOR LOCALLY DENSE. WEDNESDAY...ANOTHER ROUND OF HEAT AND CONVECTION WILL OCCUR ON WEDNESDAY. A WEAK SHORTWAVE LOOKS TO MOVE THROUGH THE PATTERN DURING THE AFTERNOON HOURS. CAPE VALUES ARE STILL QUIET HIGH AND WITH THIS TRIGGER ALOFT...EXPECT THUNDERSTORM CHANCES TO BE MORE WIDESPREAD. SHEAR VALUES ARE STRONGER NEARING 25-30KTS AND WITH PWATS AGAIN NEARING 1.5-2 INCHES...HEAVY DOWNPOURS APPEAR TO BE THE MAIN THREATS ALONG WITH GUSTY WINDS AS UPDRAFTS WILL BE ABLE TO MAINTAIN THEMSELVES. TEMPERATURES WILL BE FEEL A LITTLE COOLER WITH TEMPS ONLY REACHING INTO THE MID TO UPPER 80S. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... HEADLINES... * HEAVY RAIN THREAT PREVAILS THROUGHOUT THIS TIMEFRAME * LOCALIZED URBAN AND LOW LYING AREA FLOODING IS A POSSIBILITY * STRONG THUNDERSTORMS POSSIBLE LATE THIS WEEK INTO NEXT MONDAY * CONTINUED WARM AND MUGGY CONDITIONS 25/00Z GUIDANCE CONTINUES TO EXHIBIT OVERALL AGREEMENT WITH THEIR SYNOPTIC SOLUTIONS. THERE REMAIN SOME DETAIL DIFFERENCES...WHICH WILL TAKE SOME TIME TO RESOLVE BASED ON THE NATURE OF THE EXPECTED PATTERN FOR MOST OF THIS WEEK. HAVE LOWER CONFIDENCE IN THE DETAILS OF ANY PARTICULAR SOLUTION AT THIS TIME. AS SUCH...FOLLOWED A CONSENSUS BLEND TO MINIMIZE THE DETAIL DIFFERENCES. IT APPEARS SOUTHERN NEW ENGLAND IS IN FOR A PROLONGED STRETCH OF UNSETTLED WEATHER OVER THE NEXT SEVERAL DAYS. A MID-LEVEL BLOCKING PATTERN IS EXPECTED TO ESTABLISH ITSELF ACROSS THE NORTHERN HALF OF THE CONUS...PLACING OUR REGION JUST EAST OF A MID-LEVEL TROUGH. AT THE SURFACE...THIS WOULD MAINTAIN A GENERAL SOUTHERLY FLOW INTO THIS WEEKEND ALONG WITH HIGH HUMIDITY. TEMPERATURES SHOULD GRADUALLY MODERATE AS CLOUDS BECOME MORE PREVALENT LATE THIS WEEK. AM NOT EXPECTING A COMPLETE WASHOUT...BUT FINDING IT TOUGH TO FIND A DAY WITHOUT A CHANCE OF SHOWERS OR THUNDERSTORMS AT SOME POINT. HIGH HUMIDITY WILL POSE A RISK FOR LOCALIZED HEAVY RAINFALL IN STRONGER SHOWERS AND THUNDERSTORMS INTO EARLY NEXT WEEK. && .AVIATION /17Z TUESDAY THROUGH SATURDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM THROUGH WEDNESDAY NIGHT...MODERATE CONFIDENCE. THROUGH 00Z...MAINLY VFR. AFTER 21Z...PATCHY MVFR/IFR CONDITIONS IN SCT SHRA/TSRA. TONIGHT...MAINLY VFR. SCT SHRA/TSRA CONTINUES TO MOVE EAST THROUGH 06Z RESULTING IN BRIEF MVFR/IFR CONDITIONS. MVFR/IFR STRATUS AND FOG LIKELY ALONG THE SOUTH COAST. WEDNESDAY...ANOTHER ROUND OF SHRA/TSRA IN THE AFTERNOON HOURS. GUSTY WINDS AND REDUCED VSBYS GREATEST THREATS. WEDNESDAY NIGHT...SCT SHRA/TSRA POSSIBLE DURING THE EVENING HOURS. LOW CLOUDS/FOG POSSIBLE AGAIN ALONG THE SOUTH COAST WITH MVFR/IFR CONDITIONS. KBOS TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. KBDL TERMINAL...HIGH CONFIDENCE IN TRENDS...MODERATE CONFIDENCE IN TIMING. OUTLOOK...THURSDAY THROUGH SATURDAY... THURSDAY...SHRA/TSRA LOOK TO REMAIN CONFINED ACROSS INTERIOR NEW ENGLAND. LOCAL +RA EXPECTED. GUSTY WINDS POSSIBLE. LOW-VFR TO MVFR CIGS WITH CB ALONG WITH MVFR-IFR VSBYS POSSIBLE. PREVAILING S-SW WINDS. LLWS POSSIBLE THU NIGHT MAINLY ACROSS S COASTAL AREAS. FRIDAY AND SATURDAY... SHRA/TSRA WILL BE MORE WIDESPREAD ACROSS MOST OF SOUTHERN NEW ENGLAND...WITH THE BEST CHANCE ACROSS CENTRAL AND WESTERN AREAS. +RA EXPECTED WITH GUSTY WINDS POSSIBLE. LOW-VFR TO MVFR CIGS WITH CB ALONG WITH MVFR-IFR VSBYS POSSIBLE. PREVAILING SW WINDS. LLWS MAY BE POSSIBLE FRI THROUGH SAT ACROSS S COASTAL AREAS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM THROUGH WEDNESDAY...HIGH CONFIDENCE. TODAY INTO WEDNESDAY... A REPEAT ESSENTIALLY OF YESTERDAY. ANY MORNING FOG WILL BURN OFF BY MIDDAY AND GIVES WAY TO LATE DAY TSTMS. MAIN THREATS HEAVY RAIN AND FREQUENT LIGHTNING. THIS PATTERN WILL REPEAT INTO WEDNESDAY. ONLY CAVEAT IS THAT SCA POTENTIAL INCREASES ON WEDNESDAY AS SEAS ACROSS THE OUTER WATERS MAY REACH 5 FT THANKS TO 15-20 KTS WIND GUSTS. OUTLOOK...THURSDAY THROUGH SATURDAY... SOUTH TO SOUTHWEST WINDS MAY GUST UP TO 25 KT AT TIMES...MAINLY FRIDAY INTO SATURDAY. LONG SOUTH TO SOUTHWEST FETCH WILL BRING SEAS UP TO 5-8 FT ACROSS THE OUTER COASTAL WATERS...POSSIBLY INTO RI AND BLOCK ISLAND SOUNDS AS WELL. SCATTERED SHOWERS/TSTMS... MAINLY DURING THE AFTERNOON/EVENING HOURS. HEAVY RAIN AND FREQUENT LIGHTNING IN ANY STORMS. PATCHY FOG WITH REDUCED VSBYS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...AIR QUALITY ALERT UNTIL 10 PM EDT THIS EVENING FOR MAZ020>024. NH...NONE. RI...AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>008. MARINE...NONE. && $$ SYNOPSIS...BELK/DUNTEN NEAR TERM...RLG SHORT TERM...DUNTEN LONG TERM...BELK AVIATION...BELK/RLG MARINE...BELK/DUNTEN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
334 PM EDT TUE JUN 25 2013 .SYNOPSIS... A BERMUDA HIGH PRESSURE SYSTEM WILL KEEP THE REGION LOCKED IN A HOT AND HUMID AIRMASS THROUGH AT LEAST THURSDAY. A STRONG COLD FRONT WILL APPROACH FROM THE WEST ON THURSDAY AND CROSS THE AREA BY FRIDAY BEFORE STALLING OFF THE COAST. AS A RESULT A PERIOD OF UNSETTLED WEATHER IS EXPECTED FOR THE START OF JULY. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... NEITHER OF THE MODELS 500MB ANALYSIS LOOKED SPOT ON IN THE MIDWEST AS THE SERIES OF CONVECTIVE COMPLEXES CONTINUE TO CAUSE INITIALIZATION ISSUES. IF ANYTHING THE SYSTEMS LOOK SLIGHTLY SLOWER THAN MODELED. THERMALLY A GFS AND WRF-NMMB COMPROMISE WORK THE BEST. BUT THEY DIVERGE RATHER QUICKLY AFTER THAT. INTO THIS EVENING SCATTERED THUNDERSTORMS WILL CONTINUE TO MOVE THROUGH OUR CWA. IN GENERAL THE THERMODYNAMIC AND KINEMATIC ENVIRONMENT IS NOT ON THE LEVEL OF YESTERDAY. SO FAR THE ORIENTATION HAS BEEN MORE NORTH THAN SOUTH AND HIEST POPS WERE KEPT THERE. WHILE ONE OR TWO PULSY TYPE STORMS MIGHT REQUIRE WARNINGS THE OVERALL WEAK FCST BULK SHEAR ALONG WITH POORER MID LEVEL LAPSE RATES SHOULD KEEP THIS BELOW LEVELS OF YESTERDAY`S CONVECTION. SOME OF THE 12Z MESOSCALE MODELS (SPC WRF/NMM) WENT TOO MUCH THE OTHER WAY AND SHOWING WAY TOO LITTLE. BEST FIT IS BETWEEN THE RAP AND SLIGHTLY TONED DOWN HR3. FARTHER UPSTREAM MORE CONVECTION IS FORECAST TO DEVELOP OVER THE UPPER OHIO VALLEY. THIS ONE WILL HAVE SOME SHORT WAVE SUPPORT, BUT GIVEN ITS ARRIVAL LATER IN THIS EVENING LOWERS CONFIDENCE LEVELS AS TO SUSTAINABILITY. WE DID CARRY POPS THROUGH THE EVENING AND WE WILL SEE HOW THE PRESENT DEVELOPMENT EVOLVES. STAT GUIDANCE HAS BEEN PRETTY REASONABLE WITH MINS AND WE CONTINUE TO FOLLOW A MET/MAV BLEND. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... WE WILL ISSUE A HEAT ADVISORY FOR URBAN AREAS FOR WEDNESDAY. CONFIDENCE IS NOT THE GREATEST, BUT THIS WILL BE THE THIRD STRAIGHT DAY OF 90 PLUS HEAT AND NOT SURE IF WE ARE GOING TO GET AS MUCH COOLING FROM TSRAS TONIGHT AS LAST NIGHT. NAM MOS IS RUNNING APPROXIMATELY 3-6F TOO LOW ON HOURLY TEMPS TODAY, SO GUIDANCE WAS NOT USED ON WEDNESDAY. GFS MOS WHICH HAS VERIFIED BETTER MATCHES PRETTY CLOSELY WITH FCST 850/925MB TEMPS AS WELL AS 1000-850 THICKNESSES. OF CONCERN ALSO HAS BEEN THAT STAT GUIDANCE HAS BEEN MIXING DEW POINTS DOWNWARD TOO QUICKLY THE PAST TWO DAYS. WHETHER ITS THE LEE SIDE TROF OR JUST HOW WET THIS JUNE HAS BEEN, NOT BANKING ON THE THIRD TIME BEING THE CHARM. RIGHT NOW THIS APPEARS TO BE ONE DAY EVENT REASON FOR ADVY VS WARNING. SENSIBLE WEATHER, IF TODAY IS THE RELATIVE LULL IN CONVECTIVE ACTIVITY, WEDNESDAY IS SHOWING A TICK UP. NEARLY ALL KINEMATIC AND THERMODYNAMICALLY FORCINGS ARE SLIGHTLY STRONGER THAN TODAY. THE ONE PROBLEM WE ARE SEEING WITH WEDNESDAY IS THE SPLIT BETWEEN THE BETTER FORCING NORTHWEST AND THE GREAT INSTABILITY AND FCST MID LEVEL LAPSE RATES SE. PLUS THE FACT THE MODELS MAY BE FAST WITH THE OVERALL PROGRESSION WILL HAVE US KEEP POPS AS CHANCE. SPC SLIGHT RISK NORTHWEST HALF OF OUR CWA IS A GOOD FIT AS THAT IS CLOSER PROXIMITY TO FORCING WHICH SHOULD BE PLACE FOR A BETTER CHANCE OF ORGANIZATIONAL LINE OR CLUSTER. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... THE WARM AND STICK AMS WILL REMAIN IN PLACE WED NIGHT AND BY THU A STRONG S/WV, AND LOW PRESSURE SYS WILL APPROACH FROM THE W. THE CDFNT ASSOCD WITH THIS LOW WILL CROSS THE REGION BY FRI MRNG. WITH DEW POINTS INCREASING ON THU IT WILL REMAIN VERY UNCOMFORTABLE DESPITE MORE CLOUDS AND TEMPS A FEW DEGREES LOWER THAN ON WED. WITH A DECENTLY ROBUST LOW (FOR LATE JUNE) AND CDFNT APPROACHING, THU COULD BE THE BEST SHOT OF SHWRS AND TSTMS FOR THE WEEK. SPC HAS ALREADY PLACED A GOOD PORTION OF THE AREA GENLY WEST OF PHILADELPHIA IN A SLGT RISK. THE CDFNT WILL CROSS THE REGION BY FRIDAY BUT REMAIN CLOSE OFFSHORE. PRECIP CHCS WILL DECREASE AND FRIDAY COULD END UP BEING DRY OR MOSTLY DRY. SWLY FLOW WILL THEN PREVAIL THRU THE WEEKEND INTO NEXT WEEK AND THE FLOW WILL STRENGTHEN ANS THE TROF DEEPENS TO THE W. THIS WILL KEEP UNSETTLED WX OVER THE AREA WITH CHCS OF SHWRS AND TSTMS EACH DAY. THERE ARE NO SIGNIFICANT SYNOPTIC FEATURE OF NOTE, BUT EACH DAY`S TSTM CHCS WILL BE PARTIALLY BASED ON BOUNDARIES AND ANY S/WVS THAT MAY BE PASSING THRU THE FLOW, WHICH EACH MDL WILL HANDLE DIFFERENTLY AND ARE DIFFICULT TO DIAGNOSE AT THIS TIME SCALE. FOR NOW, WILL MAINTAIN LOW CHC POPS. MON LOOKS LIKE THERE COULD BE A WK LOW SO WILL GO A TAD HIGHER THERE, BUT CONFIDENCE REMAINS LOW ON PRECIP CHCS AND LOCATION IN THE EXTENDD PD. AFTER THU, TEMPS LOOK TO RETURN CLOSER TO NRML, BUT WILL LIKELY REMAIN SLIGHTLY ABV THRU THE PD. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. 18Z TAFS ARE CARRYING A TEMPO GROUP FOR THUNDERSTORMS THIS AFTERNOON WITH MVFR CONDITIONS FROM THE KPHL METRO AREA AIRPORTS NORTHWARD. OTHERWISE PREVAILING VFR CONDITIONS EXPECTED THROUGH THIS EVENING WITH POSSIBLY MVFR CONDITIONS LATE TONIGHT. THEN WE START ALL OVER AGAIN ON WEDNESDAY. THIS AFTERNOON BEST FORCING AND WHERE ONGOING CONVECTION IS BOTH FAVOR THUNDERSTORMS AT NORTHERN AIRPORTS AND TERMINALS. CONFIDENCE IS LESS TOWARD THE KPHL METRO AIRPORTS WHERE THEY SHOULD BE MORE ISOLATED. CONFIDENCE WAS TOO LOW AT KACY AND KMIV TO INCLUDE IN TAFS. OUTSIDE OF THAT, VFR CONDITIONS ARE FORECAST WITH WEST TO SOUTHWEST WINDS AVERAGING AROUND 10 KT. SEA BREEZE FRONT SHOULD NOT MAKE MUCH MOVEMENT OFF THE COAST. WE ARE NOT FORECASTING IT TO REACH KACY. THIS EVENING ORGANIZED THUNDERSTORMS DEVELOPING IN THE OHIO VALLEY ARE NOT FORECAST TO REACH THE TERMINALS. LOWEST CONFIDENCE KRDG. WE SHOULD JUST HAVE SOME OUTFLOW VFR MID AND HIGH LEVEL CLOUDS. SOUTHWEST WINDS AVERAGING 5 TO 10 KTS. OVERNIGHT WE CARRIED SOME MVFR CONDITIONS LATE AT THE FOGGIER MORE OUTLYING TERMINALS. THIS MIGHT NEED SOME ADJUSTMENT BASED ON ANY CONVECTION DIRECTLY AFFECTING THE AIRPORTS. WINDS SHOULD BE LIGHT. A VFR MORNING IS FORECAST FOR ALL OF THE TERMINALS WITH CU BASED CLOUDS DEVELOPING. WEST TO SOUTHWEST WINDS SHOULD INCREASE TO AROUND 10 KTS AGAIN. THE SEA BREEZE FRONT WILL STRUGGLE TO GET OFF THE COAST AGAIN, MAYBE EVEN MORE SO THAN TODAY. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE FORECAST FOR LATER WEDNESDAY, SO WE INCLUDED A PROB30 FOR KPHL AS A START. OUTLOOK... WED NIGHT INTO THU MORNING...MOSTLY VFR WITH SHORT PERIODS OF SUB-VFR IN MORNING FOG AND/OR SCT SHOWERS/TSTMS. MD CONFIDENCE. THU AFTERNOON THROUGH SAT...GENLY VFR. HOWEVER, THERE WILL BE PERIODS OF MVFR/IFR (POSSIBLY PROLONGED ONES) IN MORNING LOW CLOUDS AND FOG AND AREAS OF SHOWERS AND TSTMS. LOW CONFIDENCE. && .MARINE... THE RETURN FLOW BEHIND THE DEPARTING BERMUDA HIGH WILL KEEP A W/SW WIND ACROSS THE WATERS TODAY AND TONIGHT. WINDS/SEAS WILL REMAIN BELOW SCA CONDITIONS THRU THE PERIOD. FAIR WEATHER EXPECTED THIS MORNING...FOLLOWED BY SCT SHOWERS/TSTMS THIS AFTERNOON AND EARLY EVENING. FAIR WEATHER WILL RESUME LATER TONIGHT INTO WED MORNING. SEAS ON THE OCEAN WILL BE AROUND 2-4 FT AND 1-2 FT OVER DEL BAY. REMEMBER...WINDS AND WAVES WILL BE LOCALLY HIGHER IN TSTMS. OUTLOOK... SUB-SCA CONDITIONS ARE EXPECTED INTO THURSDAY MORNING. AFTER THAT INCREASING SWLY FLOW MIGHT BRING SCA CRITERIA MAINLY FOR SEAS, MORE SO THAN WINDS, TO THE OCEAN WATERS BEGINNING LATER THU AND PSBLY CONTINUING INTO THE WKND. RIGHT NOW CONFIDENCE REMAINS LOWER THAN AVERAGE THAT THIS WILL OCCUR AS WAVE WATCH GUIDANCE OFTEN IS TOO BULLISH UNDER THESE REGIMES. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...HEAT ADVISORY FROM 11 AM TO 8 PM EDT WEDNESDAY FOR PAZ070-071- 102-104-106. NJ...HEAT ADVISORY FROM 11 AM TO 8 PM EDT WEDNESDAY FOR NJZ015- 017>019. DE...HEAT ADVISORY FROM 11 AM TO 8 PM EDT WEDNESDAY FOR DEZ001. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...NIERENBERG NEAR TERM...GIGI SHORT TERM...GIGI LONG TERM...NIERENBERG AVIATION...GIGI/NIERENBERG MARINE...GIGI/NIERENBERG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
115 PM EDT TUE JUN 25 2013 .SYNOPSIS... BERMUDA RIDGE KEEPS THE REGION LOCKED IN A HOT AND HUMID AIRMASS THROUGH AT LEAST THE END OF THE WORK WEEK. A STRONG COLD FRONT WILL NEAR FROM THE NORTHWEST ON THURSDAY BUT BEGIN TO SLOW UPON ITS ARRIVAL. THE FRONT SHOULD LIMP THROUGH BY FRIDAY BUT THEN STALL TO OUR IMMEDIATE EAST THROUGH EARLY NEXT WEEK KEEPING A PROLONGED PERIOD OF UNSETTLED WEATHER. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 12Z UA ANALYSIS SHOWS A MUCH LESS DYNAMIC SET-UP IN OUR CWA FROM YDA AS UPSTREAM 700 AND 500 MB TEMPS ARE 2 TO 4C WARMER AND GONE IS THE STGR DPVA AND 50-60KT JET STREAK FROM YDA. 12Z WRF-NMMB KEEPS DECENT FORECAST BULK SHEAR NORTH OF OUR CWA AND FCST MID LEVEL LAPSE RATES ARE ABOUT 1C/KM LESS THAN YESTERDAY. OVERALL THINK THAT THE LATEST HR3 AND RAP HAVE A BETTER HANDLE ON THE EVOLUTION FOR THIS AFTERNOON INTO THIS EVENING THAN THE MORE CHARGED 00Z HI RES NMM AND ARW DO. NOTWITHSTANDING ABOVE AND I HAVE BEEN WRONG BEFORE AND WILL BE WRONG AGAIN (MAYBE BY 4 PM OR EVEN EARLIER), WILL HAVE TO SEE HOW CONVECTION FAR NORTH EVOLVES FROM NWRN PA AS ITS THE CLOSEST TO THE BEST FCST BULK SHEAR. WE ADJUSTED POP ORIENTATION HIGHEST NNW AND LOWEST SSE IN OUR CWA. 12Z UA ANLYS SUGGESTING NO FURTHER ADJUSTMENT TO MAX TEMPS NEEDED. SURPRISED HOW DEW POINTS ONCE AGAIN STRUGGLING TO DROP IN SPITE OF DRIER AIR AGAIN JUST ABOVE THE BOUNDARY LAYER. NUDGED THEM UPWARD AND MAX HEAT INDICES ARE CURRENTLY IN THE MID 90S. THE CURRENT RIDGING IS KEEPING THE AREA DRY THIS MORNING...BUT THEN THE DAYTIME HEATING AND THE LINGERING HUMIDITY ALONG WITH A WEAK SHORTWAVE MOVING THRU...WILL CREATE MORE SCT SHOWERS/TSTMS THIS AFTERNOON. THE COVERAGE OF THE ACTIVITY WILL NOT BE AS MUCH AS YESTERDAY...BUT THERE WILL BE ENOUGH TO KEEP THE CHC POPS IN THE FCST. THE UPPER WINDS WILL INCREASE SOMEWHAT THIS AFTERNOON...SO THE STORMS WILL HAVE A GREATER FORWARD (ERLY) MOTION. TEMPERATURES WILL ONCE AGAIN REACH THE UPPER 80S TO LOW 90S ACROSS THE AREA. THIS WILL BE DAY2 OF OUR LATEST (EXPECTED) HEAT WAVE. DEW POINT READINGS WILL PROBABLY BE A BIT LESS THAN YDAY WITH A MORE WRLY FLOW ALOFT. WE DO NOT EXPECT THAT THE APPARENT TEMPS WILL BE GREAT ENOUGH FOR ANY HEAT RELATED HEADLINES TODAY...BUT CARE SHOULD STILL BE EXERCISED FOR THOSE WHO WILL BE OUTDOORS TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... ANY LINGERING SHOWER/TSTM ACTIVITY WILL DIMINISH THIS EVENING AND ANOTHER MILD/HUMID...BUT DRY FCST IS EXPECTED. LOWS WILL ONLY DROP INTO THE LOW 70S ACROSS THE METRO AREAS AND THE DELMARVA...WHILE UPPER 60S WILL BE FOUND ACROSS NRN NJ. PATCHY FOG IS POSSIBLE ... ESPECIALLY IN AREAS THAT RECEIVE SHOWERS TODAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... 5-WAVE MODEL GUIDANCE IS SHOWING A RATHER ROBUST BLOCKING PATTERN DEVELOPING ACROSS THE REGION. A LARGE RIDGE WILL PUSH INTO THE SOUTHWEST UNITED STATES WHILE THE RIDGING DOWNSTREAM OF OUR REGION AMPLIFIES ACROSS THE WESTERN ATLANTIC. THIS PLACES US IN A DEEPENING EAST COAST TROUGH THAT LOOKS TO DEEPEN WITH TIME. THIS WILL ALSO SLOW THE PROGRESSION OF ANY WEST-EAST MOVING SYSTEMS AND EFFECTIVELY KEEP US UNSETTLED HEADING INTO THE FIRST WEEK OF JULY. BEFORE THE BLOCKING GETS FULLY SETUP WE CONTINUE WITH A RATHER PROGRESSIVE PSEUDO-ZONAL FLOW ALOFT. THE JET STREAM STILL REMAINS LOCKED FAR TO OUR NORTH ALLOWING THE HEAT AND HUMIDITY TO CONTINUE FOR THE FIRST PART OF THE LONGTERM. THIS WILL PROVIDE THE CONTINUED ONSLAUGHT OF DIURNALLY DRIVEN CONVECTION ACROSS THE AREA WEDNESDAY AND THURSDAY. ON WEDNESDAY THE SHOWERS AND THUNDERSTORMS WILL BE WIDESPREAD WITHOUT MUCH UPPER LEVEL SUPPORT SO ORGANIZATION DOES NOT SEEM TO BE AN ISSUE THOUGH LOCALLY STRONG WIND GUSTS WITH VERY HEAVY RAIN CAN NOT BE RULED OUT. 850MB TEMPERATURES JUMP CLOSE TO 20C BUT STILL THINK THAT CLOUD COVER WILL PLAGUE THE REGION EARLIER ON WEDNESDAY THAN IN DAYS PAST. THERE COULD EVEN BE ON-GOING CONVECTION THROUGH THE MORNING HOURS TO HELP HAMPER HIGHS REACHING THE MID-90S. PLAYED IT A BIT MORE CONSERVATIVE AND WENT LOW-90S ACROSS THE METRO AREA WITH WARMER TEMPERATURES OVER THE WEST AS DOWNSLOPING SHOULD HELP TO WARM THEM A COUPLE MORE DEGREES. HEADING INTO THURSDAY WE START TO SEE THE ZONAL FLOW BREAK DOWN AS A MID-LEVEL IMPULSE DROPS ACROSS THE JET AND DRAGS TO INTO THE MID-WEST. THIS WILL ALLOW FOR VERY DEEP SOUTHWESTERLY FLOW TO SETUP ACROSS THE AREA AND WILL PUMP IN EVEN MORE MOISTURE. DECENT CYCLONIC FLOW ALOFT WILL INCREASE DURING THE DAY AS HEIGHTS BEGIN TO FALL AHEAD OF THE APPROACHING IMPULSE. THURSDAY IS SETTING UP TO BE AN ACTIVE DAY ACROSS THE REGION IN TERMS OF SEVERE WEATHER. SPC HAS PUT THE WESTERN PORTIONS OF THE CWA IN A SLIGHT RISK GIVEN THE AMOUNT OF SURFACE BASED INSTABILITY THAT WILL BE PRESENT AND BETTER UPPER LEVEL SUPPORT ALLOWING FOR MORE ORGANIZED CLUSTER OF STORMS. THURSDAY COULD ALSO BE THE LAST DAY OF 90+F WE SEE THIS WEEK, BUT THIS GREATLY DEPENDS ON THE AMOUNT OF CLOUD COVER AND THE TIMING OF THE CONVECTION. FRIDAY STILL LOOKS TO PROVIDE ANOTHER ROUND FOR SEVERE WEATHER AS THE COLD FRONT, TIED TO AN ADVANCING SURFACE LOW OVER THE GREAT LAKES, NEARS FROM THE NORTHWEST. THERE SHOULD STILL BE PLENTY OF INSTABILITY LEFT OVER FROM THURSDAY TO ALLOW FOR SURFACE BASED INITIATION DURING THE LATE MORNING AND EARLY AFTERNOON HOURS WITH A FEW BREAKS IN THE OVERALL CLOUD COVER. TEMPERATURES WILL BE A FEW DEGREES COOLER ON FRIDAY THAN THURSDAY SO WE SHOULD BE ABLE TO BREAK THE CURRENT HEAT WAVE BY THEN. THE MID-LEVEL LOW SHOULD RETROGRADE A BIT DURING THE AFTERNOON HOURS ON FRIDAY SO WE LOSE A BIT OF THE COLD POOL INTERACTION BUT WE ALSO GAIN A MORE NEGATIVELY TILTED SHORTWAVE. THIS SETUP MAY MIMIC WHAT OCCURRED LATE LAST WEEK WHERE CONVECTION BEGAN LATE MORNING AND THEN FORMED INTO A LARGE BLOB OF SLOW MOVING HEAVY SHOWERS CAUSING FLASH FLOODING. GRANTED THERE IS THE LINEAR LIFTING ALONG THE COLD FRONT BUT IT REALLY DOES NOT FLY THROUGH THE REGION AND JUST SLOWLY LIMPS THROUGH. HEADING INTO THE WEEKEND WE KEEP THE MID-LEVEL TROUGH ENTRENCHED OVER THE REGION WITH PRETTY GOOD UPPER LEVEL DYNAMICS AS MULTIPLE WAVES RIDE UP THE EASTERN SEABOARD. THE UPPER JET WILL ALSO BE IN A GOOD SPOT WITH US IN ITS RIGHT ENTRANCE REGION FOR A PROLONGED TIME PERIOD. PWATS WILL STILL REMAIN VERY LARGE AND THUS WE CONTINUE TO RUN THE RISK FOR VERY HEAVY DOWNPOURS THROUGH AT LEAST EARLY NEXT WEEK. TEMPERATURES WILL BE MORE ON THE SEASONAL SIDE FROM FRIDAY ONWARD. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. 18Z TAFS WILL CARRY A TEMPO GROUP FOR THUNDERSTORMS THIS AFTERNOON WITH MVFR CONDITIONS FROM THE KPHL METRO AREA AIRPORTS NORTHWARD. OTHERWISE PREVAILING VFR CONDITIONS EXPECTED THROUGH THIS EVENING WITH POSSIBLY MVFR CONDITIONS LATE TONIGHT. THEN WE START ALL OVER AGAIN ON WEDNESDAY. THIS AFTERNOON BEST FORCING AND WHERE ONGOING CONVECTION IS BOTH FAVOR THUNDERSTORMS AT NORTHERN AIRPORTS AND TERMINALS. CONFIDENCE IS LESS TOWARD THE KPHL METRO AIRPORTS WHERE THEY SHOULD BE MORE ISOLATED. CONFIDENCE WAS TOO LOW AT KACY AND KMIV TO INCLUDE IN TAFS. OUTSIDE OF THAT, VFR CONDITIONS ARE FORECAST WITH WEST TO SOUTHWEST WINDS AVERAGING AROUND 10 KT. SEA BREEZE FRONT SHOULD NOT MAKE MUCH MOVEMENT OFF THE COAST. WE ARE NOT FORECASTING IT TO REACH KACY. THIS EVENING ORGANIZED THUNDERSTORMS DEVELOPING IN THE OHIO VALLEY ARE NOT FORECAST TO REACH THE TERMINALS. LOWEST CONFIDENCE KRDG. WE SHOULD JUST HAVE SOME OUTFLOW VFR MID AND HIGH LEVEL CLOUDS. SOUTHWEST WINDS AVERAGING 5 TO 10 KTS. OVERNIGHT WE CARRIED SOME MVFR CONDITIONS LATE AT THE FOGGIER MORE OUTLYING TERMINALS. THIS MIGHT NEED SOME ADJUSTMENT BASED ON ANY CONVECTION DIRECTLY AFFECTING THE AIRPORTS. WINDS SHOULD BE LIGHT. A VFR MORNING IS FORECAST FOR ALL OF THE TERMINALS WITH CU BASED CLOUDS DEVELOPING. WEST TO SOUTHWEST WINDS SHOULD INCREASE TO AROUND 10 KTS AGAIN. THE SEA BREEZE FRONT WILL STRUGGLE TO GET OFF THE COAST AGAIN, MAYBE EVEN MORE SO THAN TODAY. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE FORECAST FOR LATER WEDNESDAY, SO WE INCLUDED A PROB30 FOR KPHL AS A START. OUTLOOK... WEDNESDAY NIGHT INTO THURSDAY MORNING...MOSTLY VFR WITH SHORT PERIODS OF SUB-VFR IN MORNING FOG AND/OR SCT SHOWERS/TSTMS. THURSDAY AFTERNOON THROUGH SATURDAY...MORE MVFR AND IFR CONDITIONS IN MORE NUMEROUS SHOWERS/TSTMS AS WELL AS MORNING LOW CLOUDS AND FOG. && .MARINE... THE RETURN FLOW BEHIND THE DEPARTING BERMUDA HIGH WILL KEEP A W/SW WIND ACROSS THE WATERS TODAY AND TONIGHT. WINDS/SEAS WILL REMAIN BELOW SCA CONDITIONS THRU THE PERIOD. FAIR WEATHER EXPECTED THIS MORNING...FOLLOWED BY SCT SHOWERS/TSTMS THIS AFTERNOON AND EARLY EVENING. FAIR WEATHER WILL RESUME LATER TONIGHT INTO WED MORNING. SEAS ON THE OCEAN WILL BE AROUND 2-4 FT AND 1-2 FT OVER DEL BAY. REMEMBER...WINDS AND WAVES WILL BE LOCALLY HIGHER IN TSTMS. OUTLOOK... SUB-SCA CONDITIONS ARE EXPECTED INTO THURSDAY MORNING. AFTER THAT THE FORECAST INCREASING SOUTHERLY FLOW MIGHT BRING SCA CRITERIA BASED ON SWELLS, MORE SO THAN WINDS, TO THE OCEAN WATERS LATER THURSDAY THROUGH FRIDAY. CONFIDENCE RIGHT NOW REMAINS LOWER THAN AVERAGE THAT THIS WILL OCCUR AS WAVE WATCH GUIDANCE OFTEN IS TOO BULLISH UNDER THESE REGIMES. && .CLIMATE... WE STAND A PRETTY GOOD CHANCE OF HAVING THE WETTEST JUNE ON RECORD IN PHILADELPHIA. WE LOOKED BACK AT THE 10 PREVIOUS WETTEST JUNES ON RECORD AND SAW HOW THE REST OF THE METEOROLOGICAL SUMMER WENT FORWARD. WET BEGETTED(SP) MORE WET. GIVEN HOW WET THE GFS AND ECMWF LOOK INTO THE START OF JULY THAT NOTION IS HOLDING. BOTH ENSUING MONTHS AVERAGED WETTER THAN THE CURRENT NORMALS WITH EIGHT OF THE TEN MONTHS COMBINED AVERAGING WETTER THAN NORMAL. ALL OF THE MONTHS HAD TWO INCHES OR MORE OF RAINFALL. AS FAR AS TEMPERATURES WENT, JULY AVERAGED SLIGHTLY LOWER THAN THE CURRENT NORMAL, WHILE AUGUST WAS VERY CLOSE TO THE CURRENT NORMAL. SIX OF THE TEN AUGUSTS WERE AS WARM OR WARMER THAN JULY. YEAR JULY AVG JULY AUG AVG AUGUST TEMP PCPN TEMP PCPN 1887 80.7 7.14 74.0 2.31 1906 75.6 5.33 76.2 9.56 1928 77.3 3.60 77.2 5.47 1938 77.3 6.52 78.3 4.10 1962 72.0 2.30 72.0 6.58 1969 75.1 8.33 75.2 2.66 1973 77.9 2.39 78.7 2.03 1975 76.6 6.32 77.0 2.11 2003 78.7 2.01 78.2 3.26 2006 79.4 4.27 78.1 3.93 AVG 77.1 4.82 76.5 4.20 1981-2010 NML 78.1 4.35 76.6 3.50 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...HEAVENER NEAR TERM...GIGI/O`HARA SHORT TERM...O`HARA LONG TERM...HEAVENER AVIATION...GIGI/O`HARA MARINE...O`HARA CLIMATE...
AREA FORECAST DISCUSSION
NWS LINCOLN IL
317 PM CDT TUE JUN 25 2013 .DISCUSSION... ISSUED 300 PM CDT TUE JUN 25 2013 SEVERE STORM CHANCES WILL REMAIN THE FOCUS OVER THE NEXT 2 DAYS. FLASH FLOODING POTENTIAL TONIGHT IN THE NORTH WILL ALSO BE A CONCERN. BEYOND THAT...AN AIRMASS CHANGE IS PROJECTED FOR LATE THIS WEEK AND WEEKEND. HOWEVER...A CUTOFF UPPER LOW LINGERING OVER THE HEARTLAND WILL KEEP SHOWERS AND EVEN ISOLATED THUNDERSTORMS IN THE FORECAST THROUGH EARLY NEXT WEEK. SHORT TERM...TONIGHT THROUGH FRIDAY. WE DECIDED TO PUT OUR 5 NORTHERN COUNTIES IN A FLASH FLOOD THROUGH TONIGHT DUE TO PREVIOUS 3-5 INCH RAINS EARLY MONDAY MORNING AND THE POTENTIAL FOR ADDITIONAL VERY HEAVY RAINFALL RATES UP TO 2 INCHES AN HOUR WITH ANY THUNDERSTORMS THROUGH TONIGHT. PWATS REMAIN IN THE 1.7-1.9" RANGE...AND PERIODIC STORMS IN AN EAST-WEST LINE ACROSS N IL IS POSSIBLE. ADJUSTING OUR 12Z SOUNDING FOR CURRENT CONDITIONS SHOWS ML-CAPE VALUES APPROACHING 3500 J/KG ACROSS OUR AREA...WITH LITTLE TO NO CIN. VARIOUS BOUNDARIES ACROSS THE AREA FROM YESTERDAYS CONVECTION HAVE ALREADY BEGUN TO FIRE BETWEEN 18-19Z. WATER VAPOR PIX CONFIRM A SHORTWAVE IN THE FLOW ACROSS IOWA PROGRESSING EAST-NE. THAT WAVE SHOULD HELP RAMP UP THE COVERAGE OF STORMS AND POSSIBLY PUSH US INTO SEVERE WEATHER MODE. FREEZING LEVEL AT 14.4K FT MEANS HAIL WILL NEED INTENSE UPDRAFTS TO REACH SEVERE LEVELS /1"+/...BUT WE HAVE THE CAPE TO ACCOMPLISH THAT WITH THE STRONGEST STORMS. WIND SHEAR WILL BE GRADUALLY INCREASING AS WE HEAD INTO THIS EVENING...SO ROTATING SUPERCELLS WILL BE POSSIBLE AS THE EVENT PROGRESSES. THE LATEST HRRR IS INDICATING TWO PERIODS OF STORMS POSSIBLE. WE EXPECT A WAVE OF STORMS THIS EVENING THAT MAY BE FOLLOWED BY ANOTHER BOWING COMPLEX OF STORMS ROLLING INTO OUR AREA FROM IOWA REACHING KNOX COUNTY AROUND 06Z/1AM. THOSE STORMS MAY BE STILL AFFECTING OUR COUNTIES SE OF I-70 WED MORNING BEFORE THEY DEPART INTO INDIANA. WE WENT WITH SOME LIKELY POPS IN THE MORNING TO ACCOUNT FOR THAT. THEN A BREAK IN THE ACTION MAY DEVELOP THE REST OF WED MORNING AS THE ATMOSPHERE RECHARGES FOR THE AFTERNOON WAVE OF STRONG TO SEVERE STORMS. IT APPEARS THAT A LINE OF STORMS WILL DEVELOP ACROSS WEST CENTRAL ILLINOIS BY MID AFTERNOON...THEN PROGRESS EASTWARD. AN INCREASING LLJ IS EXPECTED TO COINCIDE WITH UPPER LEVEL WINDS VEERING TO THE NORTHWEST. THAT WILL INCREASE SHEAR AND HELICITY PARAMETERS AND RAMP UP THE THREAT OF ROTATING STORMS AND POSSIBLY A FEW TORNADOES...MAINLY EAST OF I-55. WE INCREASED POPS TO LIKELY IN THE EAST WEDNESDAY AFTERNOON TO ACCOUNT FOR THAT PERIOD OF SEVERE STORMS. STORMS SHOULD BE WINDING DOWN WED EVENING AS THE COMPLEX MOVES INTO INDIANA. THURSDAY AND THURSDAY NIGHT SHOULD BE PRIMARILY DRY...BUT A FEW DAYTIME SHOWERS WILL BE POSSIBLE IN THE EAST AS THE UPPER WAVE LINGERS ACROSS THE EAST...AND A FEW SHOWERS MAY REACH OUR SOUTHWESTERN COUNTIES THUR NIGHT AHEAD OF THE NEXT UPPER LEVEL WAVE. WE KEPT SLIGHT CHANCE POPS EVERYWHERE ON FRIDAY AS THAT WAVE PROGRESSES ACROSS IL. PRECIP SHOULD BE SPOTTY...AS COOLER AND LESS HUMID AIR BEGINS TO FLOW INTO THE AREA ON NORTHWEST WINDS. LONG TERM...SATURDAY THROUGH TUESDAY. WE EXPECT TO BE IN AN EXTENDED PERIOD UP UPPER LEVEL TROUGHING AS A CUT OFF LOW DEVELOPS ACROSS THE WESTERN GREAT LAKES AND RETROGRADES AND OSCILLATES OVER THE MIDWEST THROUGH EARLY NEXT WEEK. PERIODS OF SLIGHT CHANCE AND CHANCE POPS WILL PEPPER THE EXTENDED FORECAST AS A RESULT...DUE TO VARIOUS SHORTWAVE ROTATING AROUND THE UPPER LOW. RELATIVELY COOL AIR ALOFT WILL ALSO KEEP LAPSE RATES MODERATELY HIGH...AND FAVORABLE FOR ANY SUNS HEATING TO CREATE SHOWERS AND ISOLATED STORMS. TEMPS WILL SETTLE OUT WITH HIGHS IN THE UPPER 70S TO NEAR 80 AND LOWS IN THE LOWER 60S FOR MUCH OF THE EXTENDED PERIOD. SHIMON && .AVIATION... ISSUED 1252 PM CDT TUE JUN 25 2013 PERIODS OF THUNDERSTORMS ARE EXPECTED AT ALL OF THE TAF SITES IN CENTRAL AND EASTERN IL THE NEXT 24 HOURS. THE HIGH RESOLUTION MODELS LIKE THE HRRR...RUC AND LOCAL WRF ARE IN FAIR AGREEMENT THAT AT LEAST SCT CONVECTION WILL DEVELOP LATER THIS AFTERNOON IN WEST CENTRAL IL...IN RESPONSE TO ABUNDANT INSTABILITY AND A SHORTWAVE NOW MOVING TOWARD CENTRAL MO...AND IMPACT THE TAF SITES AROUND 21-23Z. AM ANTICIPATING A BRIEF RESPITE IN THE CONVECTION AS THE ATMOSPHERE LIKELY STABILIZES...DUE TO RAIN FROM LATER AFTERNOON STORMS...AROUND OR SHORTLY AFTER SUNSET. LATER IN THE EVENING AND OVERNIGHT...THE SHORT RANGE AND HIGH RESOLUTION MODELS ARE IN FAIR AGREEMENT THAT SCT CONVECTION WILL REDEVELOP CLOSE TO OR SHORTLY AFTER MIDNIGHT IN RESPONSE TO AMPLE LOW LEVEL MOISTURE AND INCREASING LOW LEVEL WINDS/MOISTURE TRANSPORT. AT THIS TIME IT APPEARS THAT THE MOST LIKELY AREA TO EXPERIENCE THIS WILL BE IN THE NORTHERN TAF SITES FROM KPIA-KBMI. AM CONFIDENT THIS WILL IMPACT THESE AREAS...SO WENT WITH A PREDOMINANT TSRA GROUP FOR A FEW HOURS BEFORE DAYBREAK. CONFIDENCE WANES WITH SOUTHWARD AND EASTWARD EXTENT AS THE MODELS DO NOT AGREE ON THE PROPAGATION OF THE STORMS. MILLER && .ILX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR ILZ027>031. && $$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
545 PM CDT TUE JUN 25 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 343 PM CDT TUE JUN 25 2013 LATEST WATER VAPOR LOOP SHOWS A WAVE MOVING ACROSS WESTERN KANSAS. SPEED LOOP OF VISIBLE SATELLITE SHOWS SOME CIRCULATION OVER NORTH CENTRAL KANSAS WITH A CU FIELD TO ITS EAST AND NORTHEAST. SURFACE TROUGH FROM A LOW IN SOUTHWEST KANSAS NORTHEAST INTO NEBRASKA. LATEST MESO ANALYSIS CONTINUES TO SHOW DEEP MOISTURE OVER EASTERN KANSAS. DEEP MOISTURE CONVERGENCE WAS OCCURRING OVER NORTHEAST AND NORTH CENTRAL KANSAS AHEAD OF THE ABOVE MENTIONED FEATURE. EML WAS WORKING ITS WAY ACROSS SOUTH CENTRAL KANSAS THIS AFTERNOON WHERE 15 DEGREE CELSIUS AIR RESIDES. THE HRRR AND WRF SHOW SOME ISOLATED CONVECTION DEVELOPING NORTH OF I-70 LATE THIS AFTERNOON AND EVENING IN NORTH CENTRAL AND NORTHEAST KANSAS. HAVE ONLY ABOUT A 10 TO 15 PERCENT CHANCE OF A THUNDERSTORM IN THE FORECAST FOR A FEW HOURS THIS EVENING. ATMOSPHERE REMAINS UNSTABLE WITH LITTLE TO NO CONVECTIVE INHIBITION. 0-6KM SHEAR NEAR 40 KTS SO COULD SEE A SUPERCELL OR TWO DEVELOP. LOW LEVEL JET VEERS TONIGHT WITH THE DEEPER MOISTURE MOVING OFF TO THE EAST. A COLD FRONT IN THE WESTERN PLAINS WILL MOVE SOUTHEAST AND ACROSS NORTH CENTRAL AND NORTHEAST KANSAS LATER TONIGHT THROUGH MID DAY WEDNESDAY. SURFACE HIGH PRESSURE WILL MOVE IN BEHIND THE FRONT ON WEDNESDAY. TEMPERATURES WILL BE MILD AGAIN TONIGHT WITH LOWS MAINLY IN THE 70S. HIGHS ON WEDNESDAY WILL BE IN THE MID 90S IN THE NORTHEAST CORNER TO NEAR 100 IN NORTH CENTRAL KANSAS. AFTERNOON HEAT INDICES IN THE 98 TO 104 DEGREE RANGE ARE EXPECTED. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 343 PM CDT TUE JUN 25 2013 THE LLVL FLOW VEERS AROUND TO THE SOUTHEAST THEN SOUTH TO SOUTHWEST WEDNESDAY NIGHT INTO THURSDAY...WARMER AIR AND DEEPER MOISTURE WILL ADVECT BACK INTO THE COUNTY WARNING AREA. A STRONG 850MB THERMAL AXIS WILL PUSH WARMER TEMPS NORTHEAST INTO THE CWA...ESPECIALLY THE SOUTHWEST COUNTIES WHERE HIGHS IN THE 100-103 RANGE SHOULD BE COMMON AS MIXING ACROSS THE AREA BY AFTERNOON DEEPENS SUBSTANTIALLY. THIS WILL NOT ONLY RAISE TEMPS...BUT AT THE SAME TIME...LOWER DEWPOINTS...MAINLY OVER THE WESTERN COUNTIES. HEAT INDICES THURSDAY WILL COMMONLY BE IN THE 100-105 RANGE. A SUBSTANTIAL EML WILL BE IN PLACE TO THE START THE AFTERNOON...BUT BY LATE IN THE DAY OVER THE NORTHERN COUNTIES...IT WILL LIKELY ERODE WITH ISOLATED THUNDERSTORMS POSSIBLE AND WILL CARRY A SLIGHT CHANCE POP. ALTHOUGH WINDS ALOFT WILL NOT BE ESPECIALLY STRONG...AN AREA OF HIGH CAPE VALUES AND INCREASING DIRECTIONAL SHEAR THROUGH 6KM WILL DEVELOP ALONG AND AHEAD OF THE BOUNDARY SLIPPING SOUTHWARD LATE IN THE DAY AND EVENING. WOULD EXPECT SOME INCREASE IN COVERAGE OF ANY LATE AFTERNOON CONVECTION. ALTHOUGH HAIL IS POSSIBLE...A DEEP LAYER OF NEARLY ADIABATIC LAPSE RATES COULD MAKE STRONG WINDS GUSTS THE PRIMARY HAZARD FOR ANY CONVECTION THAT MAY DEVELOPS. MODELS SEEM A FAIRLY GOOD AGREEMENT THAT ANY CONVECTION THAT DEVELOPS...SHOULD BE SOUTH OF THE CWA BY SUNRISE FRIDAY AS THE BOUNDARY MOVES SOUTHWARD. WILL KEEP THE HIGHEST POPS OVER THE FAR NORTHEAST/EASTERN COUNTIES. IT SHOULD ALSO MARK THE BEGINNING OF A GRADUAL DECLINE IN BOTH TEMPERATURES AND DEWPOINTS AS A LARGE SCALE UPPER TROUGH DEEPENS THROUGH THE WEEKEND OVER THE EASTERN CONUS. DEWPOINTS WILL COMMONLY BE IN THE 50S TO NEAR 60 DEGREES THROUGH THE WEEKEND. ALTHOUGH IT WILL STILL BE THE LOW TO MIDDLE 90S MOST AREAS FRIDAY...HIGHS IN THE 80S WILL BE THE RULE THROUGH THE WEEKEND INTO EARLY NEXT WEEK. WILL CARRY A SLIGHT CHANCE FOR THUNDERSTORMS OVER THE FAR NORTHEAST ON SUNDAY. ALTHOUGH CANNOT TOTALLY RULE OUT ISOLATED CONVECTION IN THE NORTHWEST FLOW REGIME OVER THE AREA...DRIER AIR OVER THE AREA AND THE LACK OF ANY CONSISTENT FORCING MECHANISM TO DEVELOP PRECIP WARRANTS KEEPING THE REMAINDER OF THE FCST DRY AT THIS POINT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 545 PM CDT TUE JUN 25 2013 LAPS ANALYSIS AND RAP PROGS SHOW THE BETTER LOW LEVEL CONVERGENCE ALONG THE SURFACE TROUGH AXIS OVER CENTRAL KS. HOWEVER THERE HAS NOT BEEN MUCH DEVELOPMENT AT ALL OF A CU FIELD IN CENTRAL KS. SO THINK THE INHIBITION TO CONVECTION IS HOLDING AND THEREFORE WILL MAINTAIN A VFR FORECAST WITHOUT ANY MENTION OF PRECIP. THE TROUGH AXIS SHOULD MOVE THROUGH THE TERMINALS LATE TONIGHT CAUSING SFC WINDS TO GRADUALLY RELAX. && .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...53 LONG TERM...63 AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
346 PM CDT TUE JUN 25 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 343 PM CDT TUE JUN 25 2013 LATEST WATER VAPOR LOOP SHOWS A WAVE MOVING ACROSS WESTERN KANSAS. SPEED LOOP OF VISIBLE SATELLITE SHOWS SOME CIRCULATION OVER NORTH CENTRAL KANSAS WITH A CU FIELD TO ITS EAST AND NORTHEAST. SURFACE TROUGH FROM A LOW IN SOUTHWEST KANSAS NORTHEAST INTO NEBRASKA. LATEST MESO ANALYSIS CONTINUES TO SHOW DEEP MOISTURE OVER EASTERN KANSAS. DEEP MOISTURE CONVERGENCE WAS OCCURRING OVER NORTHEAST AND NORTH CENTRAL KANSAS AHEAD OF THE ABOVE MENTIONED FEATURE. EML WAS WORKING ITS WAY ACROSS SOUTH CENTRAL KANSAS THIS AFTERNOON WHERE 15 DEGREE CELSIUS AIR RESIDES. THE HRRR AND WRF SHOW SOME ISOLATED CONVECTION DEVELOPING NORTH OF I-70 LATE THIS AFTERNOON AND EVENING IN NORTH CENTRAL AND NORTHEAST KANSAS. HAVE ONLY ABOUT A 10 TO 15 PERCENT CHANCE OF A THUNDERSTORM IN THE FORECAST FOR A FEW HOURS THIS EVENING. ATMOSPHERE REMAINS UNSTABLE WITH LITTLE TO NO CONVECTIVE INHIBITION. 0-6KM SHEAR NEAR 40 KTS SO COULD SEE A SUPERCELL OR TWO DEVELOP. LOW LEVEL JET VEERS TONIGHT WITH THE DEEPER MOISTURE MOVING OFF TO THE EAST. A COLD FRONT IN THE WESTERN PLAINS WILL MOVE SOUTHEAST AND ACROSS NORTH CENTRAL AND NORTHEAST KANSAS LATER TONIGHT THROUGH MID DAY WEDNESDAY. SURFACE HIGH PRESSURE WILL MOVE IN BEHIND THE FRONT ON WEDNESDAY. TEMPERATURES WILL BE MILD AGAIN TONIGHT WITH LOWS MAINLY IN THE 70S. HIGHS ON WEDNESDAY WILL BE IN THE MID 90S IN THE NORTHEAST CORNER TO NEAR 100 IN NORTH CENTRAL KANSAS. AFTERNOON HEAT INDICES IN THE 98 TO 104 DEGREE RANGE ARE EXPECTED. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 343 PM CDT TUE JUN 25 2013 THE LLVL FLOW VEERS AROUND TO THE SOUTHEAST THEN SOUTH TO SOUTHWEST WEDNESDAY NIGHT INTO THURSDAY...WARMER AIR AND DEEPER MOISTURE WILL ADVECT BACK INTO THE COUNTY WARNING AREA. A STRONG 850MB THERMAL AXIS WILL PUSH WARMER TEMPS NORTHEAST INTO THE CWA...ESPECIALLY THE SOUTHWEST COUNTIES WHERE HIGHS IN THE 100-103 RANGE SHOULD BE COMMON AS MIXING ACROSS THE AREA BY AFTERNOON DEEPENS SUBSTANTIALLY. THIS WILL NOT ONLY RAISE TEMPS...BUT AT THE SAME TIME...LOWER DEWPOINTS...MAINLY OVER THE WESTERN COUNTIES. HEAT INDICES THURSDAY WILL COMMONLY BE IN THE 100-105 RANGE. A SUBSTANTIAL EML WILL BE IN PLACE TO THE START THE AFTERNOON...BUT BY LATE IN THE DAY OVER THE NORTHERN COUNTIES...IT WILL LIKELY ERODE WITH ISOLATED THUNDERSTORMS POSSIBLE AND WILL CARRY A SLIGHT CHANCE POP. ALTHOUGH WINDS ALOFT WILL NOT BE ESPECIALLY STRONG...AN AREA OF HIGH CAPE VALUES AND INCREASING DIRECTIONAL SHEAR THROUGH 6KM WILL DEVELOP ALONG AND AHEAD OF THE BOUNDARY SLIPPING SOUTHWARD LATE IN THE DAY AND EVENING. WOULD EXPECT SOME INCREASE IN COVERAGE OF ANY LATE AFTERNOON CONVECTION. ALTHOUGH HAIL IS POSSIBLE...A DEEP LAYER OF NEARLY ADIABATIC LAPSE RATES COULD MAKE STRONG WINDS GUSTS THE PRIMARY HAZARD FOR ANY CONVECTION THAT MAY DEVELOPS. MODELS SEEM A FAIRLY GOOD AGREEMENT THAT ANY CONVECTION THAT DEVELOPS...SHOULD BE SOUTH OF THE CWA BY SUNRISE FRIDAY AS THE BOUNDARY MOVES SOUTHWARD. WILL KEEP THE HIGHEST POPS OVER THE FAR NORTHEAST/EASTERN COUNTIES. IT SHOULD ALSO MARK THE BEGINNING OF A GRADUAL DECLINE IN BOTH TEMPERATURES AND DEWPOINTS AS A LARGE SCALE UPPER TROUGH DEEPENS THROUGH THE WEEKEND OVER THE EASTERN CONUS. DEWPOINTS WILL COMMONLY BE IN THE 50S TO NEAR 60 DEGREES THROUGH THE WEEKEND. ALTHOUGH IT WILL STILL BE THE LOW TO MIDDLE 90S MOST AREAS FRIDAY...HIGHS IN THE 80S WILL BE THE RULE THROUGH THE WEEKEND INTO EARLY NEXT WEEK. WILL CARRY A SLIGHT CHANCE FOR THUNDERSTORMS OVER THE FAR NORTHEAST ON SUNDAY. ALTHOUGH CANNOT TOTALLY RULE OUT ISOLATED CONVECTION IN THE NORTHWEST FLOW REGIME OVER THE AREA...DRIER AIR OVER THE AREA AND THE LACK OF ANY CONSISTENT FORCING MECHANISM TO DEVELOP PRECIP WARRANTS KEEPING THE REMAINDER OF THE FCST DRY AT THIS POINT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1249 PM CDT TUE JUN 25 2013 SOUTH WINDS WILL INCREASE TO AROUND 18 KTS WITH GUSTS AS HIGH AS 30 KTS THROUGH 02Z. SOUTH TO SOUTHWEST WINDS NEAR 10 KTS TONIGHT. A COLD FRONT WILL MOVE THROUGH THE TERMINALS IN THE 11Z-14Z TIME FRAME WEDNESDAY. SOME ISOLATED CONVECTION IS POSSIBLE THROUGH 06Z BUT CONFIDENCE NOT HIGH ENOUGH TO ADD VCTS ATTM. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...53 LONG TERM...63 AVIATION...53
AREA FORECAST DISCUSSION
NWS PADUCAH KY
326 PM CDT TUE JUN 25 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 325 PM CDT TUE JUN 25 2013 A FEW ISOLATED THUNDERSTORMS WILL BE POSSIBLE THROUGH SUNSET OVER THE ENTIRE AREA...BUT THE PRIMARY FOCUS LOOKS TO BE ALONG THE NORTHWEST PERIPHERY OF THE AREA AND FARTHER NORTH LATE THIS AFTERNOON. ANY ACTIVITY TO OUR NORTH WOULD LIKELY MOVE EASTWARD...BUT COULD BUILD SOUTHWARD INTO OUR FAR NORTH OR NORTHEAST COUNTIES THIS EVENING. LEFT A SLIGHT CHANCE THROUGH THE EVENING ALONG THE NORTHEAST PERIPHERY OF THE AREA. DUE TO THE EXTREME INSTABILITY ACROSS THE AREA...A FEW STORMS COULD BRIEFLY PULSE UP TO PRODUCE MARGINALLY SEVERE HAIL OR WINDS...BUT THE PRIMARY CONCERN WILL BE LOCALLY HEAVY RAINFALL. THE LATEST HRRR AND 12Z WRF RUNS INDICATE THAT AN MCS MAY BE APPROACHING THE AREA FROM THE NORTHWEST BY 12Z. THE FLOW ALOFT WILL BEGIN TO SHIFT TO THE NORTHWEST TONIGHT...SO THIS GENERAL SYSTEM MOVEMENT IS LIKELY. THE MODELS GENERALLY WEAKEN THE SYSTEM AS IT ENCOUNTERS THE WEAKER FLOW OVER OUR AREA. IT IS NOT CERTAIN WHETHER THE ACTIVE CONVECTION WILL REACH THE AREA...BUT AN OUTFLOW BOUNDARY WILL AT LEAST GET VERY CLOSE TO THE AREA. TWO THINGS TO CONSIDER HERE ARE THE POTENTIAL FOR THE OLD COLD POOL TO SURGE INTO THE AREA...MUDDLING UP THE OTHERWISE HOT...HUMID AND BREEZY DAY THAT IS CURRENTLY FORECAST...AND THE POTENTIAL FOR THE OUTFLOW TO FOCUS NEW THUNDERSTORM DEVELOPMENT OR JUST RE-INTENSIFY OVER OUR AREA DURING THE DAY. THE MODELS HAVE CONSISTENTLY INDICATED INCREASING SHEAR THROUGH THE DAY FROM THE NORTHWEST...AND DEVELOPED RATHER EXTREME INSTABILITY SOUTH OF ANY OUTFLOWS IN THE AFTERNOON. THEREFORE...WOULD NOT EXPECT ANY CONVECTION THROUGH THE MORNING TO POSE MORE THAN A HEAVY RAIN THREAT. HOWEVER...NO MATTER THE MEANS OF GENERATION...STORMS LATER INTO THE AFTERNOON AND THROUGH THE EVENING WILL LIKELY POSE A LARGE HAIL AND DAMAGING WIND THREAT. THE STORMS WILL MOVE TO THE SOUTHEAST...AND ANY RIGHT MOVING STORMS MAY MOVE DUE SOUTH OR EVEN SOUTHWEST. IN THE ABSENCE OF A MAJOR COLD POOL INVASION EARLY WEDNESDAY...A LAKE WIND ADVISORY AND POSSIBLY A HEAT ADVISORY WILL BE NEEDED THROUGH THE DAY. WILL NOT ISSUE EITHER AT THIS TIME DUE TO THE UNCERTAINTIES IN THE OVERNIGHT CONVECTIVE FORECAST. PRESUMABLY IT WILL BE A CLEARER DECISION FOR THE MIDNIGHT SHIFT. AS FOR TEMPERATURES...WENT ON THE MILD SIDE OF MOST GUIDANCE FOR TONIGHT...AND EVEN WEDNESDAY NIGHT GIVEN NO SIGN OF SIGNIFICANT DRY ADVECTION INTO THE AREA. HIGHS ON WEDNESDAY ARE LIKELY TO BE A REAL PAIN. TRIED TO KEEP IT HOT IN THE WEST AND COOL IT DOWN A BIT IN THE EAST CLOSER TO ANY ALL DAY OUTFLOW/CONVECTION POTENTIAL. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 325 PM CDT TUE JUN 25 2013 THIS EXTENDED PERIOD ESSENTIALLY STARTS FOLLOWING THE PASSAGE OF THE CLOSED LOW THROUGH THE GREAT LAKES AND THE APPROACH OF THE WESTERN U.S. RIDGE. THE WFO PAH AREA IS POISED ON THE SOUTHERN EDGE OF THE BAROCLINIC ZONE EMBEDDED IN FAST NORTHWEST FLOW. THE PENNYRILE REGION OF WEST KENTUCKY AND SOUTHWEST INDIANA ARE ON THE WEST EDGE OF THE FOCUSED LIFT/STRETCHING OF PARCELS...SO KEPT A SMALL MENTION OF THUNDERSTORMS IN THAT AREA. THE SHORT RANGE ENSEMBLE /SREF/ SUGGESTS THAT THERE WILL BE A WEAK BOUNDARY INTERACTION ALONG THE SOUTHERN SECTIONS OF THE WFO PAH FORECAST AREA INTO THURSDAY NIGHT /MAINLY OVER SOUTHEAST MISSOURI AND WEST KENTUCKY/ TANGENTIAL TO THE FASTER NORTHWEST FLOW. WITH THIS IN MIND...KEPT A SMALL CHANCE OF THUNDERSTORMS ADJACENT TO THE BOUNDARY. FROM FRIDAY INTO FRIDAY EVENING...ALTHOUGH THE SURFACE FLOW IS NORTHWEST...THERE IS SOME DIFFERENTIAL SPEED SHEAR AND LOW LEVEL THERMAL GRADIENT ALONG THE SOUTHERN EDGE OF THE WESTERLIES...WITH MEAGER LOW/MID LEVEL MOISTURE IN THE WFO PAH FORECAST AREA. AT THIS TIME...NOT REAL CONFIDENT THAT THERE WILL BE MUCH GREATER THAN WIDELY SCATTERED COVERAGE FOR CONVECTION...SO POPS/WEATHER ARE A LITTLE LOWER THAN SURROUNDING NWS OFFICES AT THIS TIME. THE GFS/GFS ENSEMBLE TAKES THE PREVIOUSLY MENTIONED GREAT LAKES LOW AND ROTATE ANOTHER SHORTWAVE AROUND THE LOW DOWN THROUGH THE UPPER MIDWEST ON SATURDAY. WITH THIS NEXT SHORTWAVE...THERE IS SOME SUPPORT FOR ELEVATED CONVECTION BY NEXT SUNDAY. FROM MONDAY INTO TUESDAY...AS THE LOW SHARPENS OVER THE WFO PAH FORECAST AREA...INTRODUCED A CHANCE FOR CONVECTION ALONG THE EASTERN LIMB OF THE SHARPENING TROUGH...MAINLY OVER THE PENNYRILE REGION OF WEST KENTUCKY AND SOUTHWEST INDIANA. THERE WOULD BE A SLIGHT TEMPORAL SHIFT WESTWARD AS IMPULSES WORK THROUGH THE BASE OF THE TROUGH. TEMPERATURE-WISE...THERE WILL BE SOME VARIANCE AS THE THE SOUTHERN LIMIT OF THE ANTECEDENT CONVECTION WEDNESDAY AND WEDNESDAY NIGHT...ALONG WITH THE POSITION OF THE EFFECTIVE BOUNDARY OVER THE WFO PAH FORECAST AREA. AT THIS TIME...LEANED TOWARD THE SREF SOLUTION. THIS WILL PLACE A SHARP THERMAL GRADIENT OVER SOUTHEAST MISSOURI...WITH HIGH TEMPERATURES EXPECTED TO TOP OUT INTO THE UPPER 90S...WITH WIDESPREAD HEAT INDEX VALUES BETWEEN 100 AND 105 DEGREES ALONG AND WEST OF THE MISSISSIPPI RIVER. BEYOND THURSDAY... TEMPERATURES SHOULD REMAIN AT OR BELOW NORMAL WITH HIGHS FALLING BACK INTO THE 80S. && .AVIATION... ISSUED AT 103 PM CDT TUE JUN 25 2013 KEPT THE 18Z TAFS REAL SIMPLE. DID NOT INCLUDE ANY TS THIS AFTERNOON...AS ISOLATED COVERAGE IS NOT LIKELY TO DIRECTLY IMPACT ANY OF THE TERMINALS. NICE CU FIELD AND SOUTHWEST WINDS GUSTING INTO THE TEENS WILL CONTINUE THROUGH THE AFTERNOON. THE PRESSURE GRADIENT WILL REMAIN TIGHT ENOUGH TO SUPPORT A SOUTHERLY BREEZE THROUGHOUT THE AREA TONIGHT. AS STATED IN THE UPDATE SECTION THE POTENTIAL EXISTS FOR CONVECTION TO MOVE SOUTHWARD INTO THE AREA OVERNIGHT INTO WEDNESDAY MORNING. HOWEVER...CONFIDENCE IS TOO LOW IN THE TIMING...LOCATION AND DIRECTION OF MOVEMENT OF ANY SUCH COMPLEX TO MENTION IN THE TAFS AT THIS TIME. NICE CU FIELD AND GUSTIER SOUTHWEST WINDS ARE EXPECTED TO DEVELOP MID TO LATE WEDNESDAY MORNING...AND TS POTENTIAL WILL BE INCREASING THROUGH THE LATE MORNING...ESPECIALLY IN THE NORTHEAST. SO...MENTIONED PROB30 FOR VFR TS IN THE NORTHEAST IN THE LAST FEW HOURS OF THE TAF PERIOD. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...DRS LONG TERM...SMITH AVIATION...DRS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
245 PM EDT TUE JUN 25 2013 .SYNOPSIS... WARM AND HUMID CONDITIONS WILL CONTINUE. IN ADDITION...SEVERAL UPPER LEVEL DISTURBANCES WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS UNTIL A COLD FRONT PASSES ON THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... LOOKS LIKE CONVECTION WILL CONTINUE TO DEVELOP IN THE VICINITY OF THE TRAILING OUTFLOW BOUNDARY THAT IS CURRENTLY SET UP ROUGHLY ALONG THE I-80 CORRIDOR. WHILE THE MESOSCALE ANALYSIS SUGGESTS PLENTY OF INSTABILITY...WITH CAPE IN EXCESS OF 2500-3000 J/KG...SHEAR CONTINUES TO REMAIN MARGINAL AT BEST. THIS HAS LEAD TO VERY DISORGANIZED STORMS THUS FAR. HOWEVER...SEVERAL OF THE HI RES MODELS ARE CONTINUING TO SUGGEST A BIT MORE ORGANIZATION BY LATE THIS AFTERNOON. BOTH THE HRRR AND 4KM NAM SUGGEST THAT A MCS WILL DEVELOP AND PROPAGATE ALONG THIS SLOWLY SINKING BOUNDARY MENTIONED ABOVE...CROSSING THE FORECAST AREA BY 8PM. NOT COMPLETELY SOLD ON MCS DEVELOPMENT BUT...SINCE THE DETERMINISTIC MODELS CONTINUE TO SHOW A BREAK DOWN IN THE RIDGE AS A WEAK SHORTWAVE MOVES ACROSS THE GREAT LAKES THIS EVENING...BELIEVE THIS COULD BE ENOUGH TO AT LEAST HELP SOME STORMS REACH STRONG TO SEVERE LEVELS. FOR NOW...CONTINUED THE SCATTERED COVERAGE WORDING FOR THUNDERSTORMS AND WILL CONTINUE TO MONITOR UPSTREAM TRENDS. A SIMILAR SCENARIO REMAINS IN PLACE FOR WEDNESDAY. MODEL SOUNDINGS CONTINUE TO SUGGEST A BRIEF NORTHWESTERLY WIND COMPONENT AT MID LEVELS COULD POSSIBLY HELP SUPPORT STRONGER STORMS WEDNESDAY AFTERNOON...BUT COVERAGE REMAINS UNCERTAIN. A PERSISTENCE FORECAST FOR TEMPERATURES WAS MAINTAINED THROUGH THE PERIOD. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... STRONG AGREEMENT AMONGST NCEP CHAIN ON A MODEST MID LVL WAVE CROSSING THE WESTERN GREAT LAKES WED NGT INTO THUR. CONFIDENCE HAS INCREASED TO RAISE POPS FURTHER INTO THE CATEGORICAL RANGE. TIME OF DAY DOES NOT LEND ITSELF TO HAZARDOUS WEATHER...SO PRESENT THINKING IS WE EXPERIENCE A WELCOME RAIN WITH SCATTERED SUB-SEVERE STORMS. PROGRESSIVE PATTERN WITH IMPULSES CROSSING EVERY 18 TO 24 HOURS DOES NOT LEND ITSELF MUCH TIME FOR INSERTION OF DRY WEATHER. CONTINUED WITH CHANCE POPS THE BALANCE OF SHORT TERM AS INHERITED DATASET PRESENTLY ILLUSTRATES. THERMODYNAMIC PARAMETERS ARE NOT IMPRESSIVE FRIDAY FOR A SEVERE THREAT DESPITE A STRONG KINEMATIC ENVIRONMENT. SBCAPES PUSH 2.0 KJKG-1 W OF I-77 ALONG WITH BETTER BL EQUIV POT TEMP ADV...BUT MID LVL LAPSE RATES ARE MARGINAL /AROUND 5CKM-1 OR LESS/. AS H5 CYCLONE COILS UP ACRS EASTERN CANADA...ASSOCIATED HEIGHT FALLS WILL BRING COOLER AND LESS HUMID WEATHER OVER THE WEEKEND. INTERSECTION OF INSTABILITY AND LIFT WILL COINCIDE ON THE LEADING EDGE OF H7-H3 DCVA SUPPORTING RW/TRW DEVELOPMENT CLOSER TO LAKE ERIE. A COLD FRONT ENCROACHES SAT NGT BUT LIMITED MOISTURE ACCOMPANIES IT. DUE TO STAGNANT PATTERN LEANED HEAVILY ON BIAS CORRECTED MOSGUIDE GRIDS FOR TEMPS WHICH HAVE PREFORMED WELL RECENTLY. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... A SERIES OF SHRTWVS WL CONT TO DROP SE ACRS THE GT LKS RGN THRU MOST OF THE PD. THIS WL SPPRT SHWR/TSTM CHCS AT LEAST THRU SAT. MOISTURE MORE IN QUESTION BY SUN SO ONLY MENTIONED SLGT CHC POPS THEN. OTRW...WENT NO HIGHER THAN CHC POPS ATTM DUE TO TIMING UNCERTAINTIES IN INDIVIDUAL SHRTWVS. EXP TEMPS NR OR A SLGTLY ABV SEASONAL AVGS UNTIL HIGH PRES BLDS IN LT IN THE PD WITH SLGTLY BLO AVG READINGS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... VFR CONDS CURRENTLY. BECOMING MORE UNSTABLE AS THE HEATING CONTINUES. DISTURBANCE MOVING ALONG THE OUTFLOW BOUNDARY FROM THE OVERNIGHT MCS WILL BE THE FOCUS OF THE NEXT CLUSTER OF STORMS THAT WILL MOVE THROUGH THE TAF SITES EARLY THIS EVENING WITH MVFR RESTRICTIONS IN TSRA. PTCHY MVFR IN BR IS PSBL FOR MANY TAF SITES DURING THE SUNRISE HOURS ON WEDNESDAY. OUTLOOK.../WEDNESDAY THROUGH SATURDAY/... VFR IS EXPD MUCH OF THE TIME...ALTHOUGH A SERIES OF DISTURBANCES WL BRING DAILY CHCS OF SHWRS/TSTMS WITH THE HIGHEST CHC BEING THU/THU NGT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
431 PM EDT TUE JUN 25 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 430 PM EDT TUE JUN 25 2013 WV IMAGERY AND RUC ANALYSIS INDICATED A LOW AMPLITUDE PATTERN WITH A TROUGH INTO THE PAC NW AND A RIDGE FROM THE UPPER MS VALLEY INTO MANITOBA. THE MAIN UPSTREAM SHORTWAVE TROUGH EXTENDED FROM ERN MONTANA INTO WRN SD. AT THE SFC...A WEAK RIDGE AND LIGHT PRES GRADIENT PREVAILED OVER THE THE REGION ALLOWING PROMINENT LAKE BREEZES TO DEVELOP. CAPPING HAS BEEN STRONG ENOUGH TO SUPPRESS CONVECTION THROUGH 20Z DESPITE LOW LEVEL CONV...INLAND MLCAPE VALUES TO NEAR 1500 J/KG AND CU/TCU LINE DEVELOPMENT. MIXING HAS ALSO BEEN STRONG ENOUGH TO DROP DEWPOINTS INTO THE MID AND UPPER 50S NEAR THE WI BORDER TONIGHT...POTENTIAL REMAINS FOR SOME ISOLD SHRA/TSRA DEVELOPMENT...MAINLY OVER THE SOUTH NEAR THE LAKE BREEZE BOUNDARIES. WITH THE LOSS OF DAYTIME HEATING...ANY PCPN CHANCES WILL ALSO DIMINISH THIS EVENING. EVEN WITH FAVORABLE RADIATIONAL COOLING OVERNIGHT...ENOUGH LOW LEVEL MOISTURE REMAINS TO KEEP MIN TEMPS FROM DROPPING MUCH BELOW 60F. SOME PATCHY FOG MAY ALSO DEVELOP. WED...THE NRN PLAINS SHRTWV AND ASSOCIATED SFC TROUGH MOVING INTO THE WRN LAKES WILL BE THE FOCUS FOR SHRA/TSRA DEVELOPMENT. THE MODELS WERE IN RELATIVELY GOOD AGREEMENT BRINGING THE HIGHER PCPN CHANCES INTO THE WEST HALF OF THE CWA DURING THE AFTERNOON. THE AIRMASS OVER REGION SHOULD AGAIN ALLOW TEMPS TO CLIMB INTO THE LOWER 80S INLAND AND BEFORE LAKE BREEZES TAKE OVER. MLCAPE VALUES MAY AGAIN CLIMB TO AROUND 1500 J/KG BUT RELATIVELY MODEST SHEAR VALUES WILL LIMIT STRONG/SEVERE STORM POTENTIAL. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 430 PM EDT TUE JUN 25 2013 OVERALL PATTERN WILL EVOLVE INTO AN AMPLIFIED ONE FOR LATE JUNE STANDARDS DURING THE LATE WEEK PERIOD WITH INTENSE UPPER RIDGING DEVELOPING OVER THE WESTERN U.S. AND TROUGHING DEVELOPING OVER THE GREAT LAKES AND EASTERN U.S. AS HAS BEEN THE CASE OVER THE LAST SEVERAL DAYS TIMING OF A BETTER PRECIP CHANCES DURING THE NEXT COUPLE OF DAYS WILL REMAIN A CHALLENGE. CONFIDENCE IS PRETTY HIGH THAT ALL AREAS WILL SEE AT LEAST SOME RAINFALL BETWEEN THE WEDNESDAY NIGHT THROUGH SATURDAY TIME PERIOD. HOWEVER...MORE OF THAT TIME WILL BE DRY RATHER THAN RAINY. WHILE SCATTERED POPS SEEM THE WAY TO GO FOR THIS TIME PERIOD...WILL GO WITH SLIGHTLY HIGHER POPS DURING THE WED NIGHT TIME PERIOD AS SHORTWAVE ENERGY BEGINS TO CARVE OUT UPPER TROUGHING OVER THE GREAT LAKES. WILL ALSO GO ON THE HIGHER END OF CHANCE POPS FOR FRIDAY INTO SATURDAY AS MAIN TROUGH AXIS MOVES THROUGH THE AREA. A SCATTERING OF POPS DURING THE OTHER PERIODS SEEMS REASONABLE. WITH LIMITED INSTABILITY AND SHEAR EXPECTED...THUNDER CHANCES WILL BE MORE IN THE ISOLATED TO SLIGHT CHANCE RANGE. HIGH PRESSURE AND DRIER AIR SHOULD BEGIN PUSHING INTO THE AREA FROM THE NORTH BY LATE IN THE DAY SATURDAY ENDING THE RAIN CHANCES. UPPER TOUGHING WILL REMAIN OVER THE AREA INTO EARLY NEXT WEEK KEEPING TEMPERATURES AT TO JUST SLIGHTLY BELOW NORMAL THROUGH THE WEEKEND INTO MONDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 154 PM EDT TUE JUN 25 2013 MAINLY VFR CONDITIONS WILL PREVAIL THRROUGH THIS FCST PERIOD AT KIWD/KCMX/KSAW. RADIATAIONAL COOLING MAY ALLOW SOME FOG TO DEVELOP LATE TONIGHT AT SAW/IWD DROPPING VSBY INTO THE MVFR RANGE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 430 PM EDT TUE JUN 25 2013 OVERALL...WINDS ARE EXPECTED TO BE BELOW 20KTS THROUGH THE PERIOD AS THE PRESSURE PATTERN REMAINS FAIRLY WEAK ACROSS THE AREA. WITH THE WARM MOIST AIR OVER THE UPPER GREAT LAKES...WILL CONTINUE TO MENTION PATCHY/AREAS OF FOG THROUGH WEDNESDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...MZ AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
348 PM CDT TUE JUN 25 2013 .SHORT TERM...(THROUGH LATE TONIGHT) ISSUED AT 344 PM CDT TUE JUN 25 2013 SEVERAL THINGS TO DEAL WITH IN THE SHORT TERM TONIGHT. FIRST...STORMS DEVELOPING IN WARM SECTOR AHEAD OF MCV THAT IS SLIDING EAST THROUGH MO FROM MCS THAT WAS OVER WESTERN MO THIS MORNING...AS WELL AS VARIOUS OLD OUTFLOW BOUNDARIES. THIS ACTIVITY SHOULD DIMINISH MOST LOCATIONS BY EARLY THIS EVENING...THOUGH SOME LINGERING ACTIVITY OVER NORTHEAST MO/WEST CENTRAL IL AS MCV SLIDES EAST. THEN MODELS CONTINUE TO SHOW NEXT MCS DEVELOPING OVER IOWA. FORECAST CORFIDI VECTORS HAVE THIS MCS SLIDE SOUTHEAST TOWARDS FORECAST AREA...MAYBE EVEN MORE SOUTHERLY. SO SHOULD MOVE INTO NORTHERN PORTIONS OF FORECAST AREA BY 06Z. LATEST HRRR RUN IS EVEN FURTHER WEST WITH INITIAL DEVELOPMENT IN SOUTHERN IOWA...SO HAVE RAISED POPS A BIT FURTHER WEST. THERE IS A SLIGHT RISK OF SEVERE WEATHER...WITH THE MAIN THREATS BEING LARGE HAIL AND DAMAGING WINDS. AS FOR TEMPS...TO REMAIN RATHER MILD WITH LOWS IN THE LOW TO MID 70S OVERNIGHT. BYRD .LONG TERM...(WEDNESDAY THROUGH NEXT TUESDAY) ISSUED AT 344 PM CDT TUE JUN 25 2013 COMPLEX SCENARIO ON TAP FOR WEDNESDAY WITH LOTS OF UNCERTAINTY TO SPECIFIC FORECAST DETAILS. THE MAIN COMPLICATING FACTOR IS THE OVERNIGHT MCS EXPECTED TO IMPACT WESTERN IL AND PORTIONS OF ERN MO AND WHERE IT WILL BE LOCATED AT DAYBREAK. A CONSENSUS OF MODEL SOLUTIONS HAVE THE DECAYING MCS IN CENTERED THRU IL AT DAYBREAK WITH THE TRAILING FLANK OR BOUNDARY LOCATED ALONG THE MS RIVER IN ERN MO. THE VEERED NATURE OF THE TROPOSPHERIC WINDS AND WLY LLJ WOULD SUGGEST THIS SYTEM SHOULD CONTINUE TO MOVE SEWD IN A DECAYING STATE THROUGH THE MORNING WITH POTENTIAL FOR SOME STORMS ON THE TRAILING BOUNDARY. STRONG HEATING SHOULD COMMENCE DURING THE DAY WITHIN THE WARM SECTOR AHEAD OF THE ENCROACHING COLD FRONT...AS WELL AS WEST OR SOUTHWEST OF ANY REMANANT BOUNDARIES. THE HEATING WILL BE MORE LIMITED WITH EASTWARD EXTENT DUE TO RESIDUAL CLOUDINESS FROM THE MORNING...BUT THE WARM SECTOR IS EXPECTED TO BECOME VERY UNSTABLE AND WEAKLY CAPPED WITH SBCAPE AOA 4000 J/KG. SCATTERED THUNDERSTORMS ARE EXPECTED TO REDEVELOP IN THE AFTERNOON WITHIN THE CONFLUENT ZONE AHEAD OF THE COLD FRONT AND WITH ANY RESIDUAL BOUNDARIES...PRIMARILY FROM EAST CENTRAL/SE MO INTO SOUTH CENTRAL AND SW IL. DEEP LAYER SHEAR OF 30-40 KTS AND THE AMOUNT OF INSTABILITY WOULD FAVOR SUPERCELL AND MULTICELL MODES. THE MORNING CONVECTION AND/OR RESIDUAL CLOUDS PRESENT SOME PROBLEMS WITH RESPECT TO THE MAGNITUDE OF HEAT. I HAVE COOLED TEMPS SLIGHTLY FROM ST LOUIS EASTWARD AND THIS IS HIGHLY DEPENDENT ON MORNING CLOUDS. GIVEN THE UNCERTAINTIES I HAVE DEFERED ON ANY HEAT ADVISORIES WITH HEAT INDICES FORECAST IN THE 100-105 RANGE. STORMS SHOULD BE CLOSE TO EXITING THE CWA OR WILL HAVE EXITED THE CWA BY 00Z THURSDAY. EVEN IN THE WAKE OF THE INITIAL COLD FRONT/BOUNDARY...THURSDAY LOOKS LIKE ANOTHER SEASONABLY HOT DAY. INFACT...IT IS NOT TOTALLY OUT OF THE QUESTION IT COULD BE HOTTER THAN WEDNESDAY BUT WITH LESSER HUMIDITY. THE ANTICIPATED NORTHWEST FLOW SHORTWAVE AND SECONDARY COLD FRONT WILL MOVE THROUGH THE AREA LATE THURSDAY NIGHT INTO EARLY FRIDAY WITH A PROMINENT WSW LLJ AHEAD OF IT. THIS SHOULD FUEL ANOTHER MCS WHICH WILL IMPACT PORTIONS OF THE CWA. THE MODELS DIVERGE ON THE MCS TRACK WITH THE GREATEST PROBABILITY ATTM APPEARING TO BE THROUGH CENTRAL MO. MUCH COOLER AIR WILL THEN SPREAD INTO THE AREA IN THE WAKE OF THE FRONT FOR FRIDAY AND SET THE STAGE FOR A PROLONGED PERIOD OF BELOW AVERAGE TEMPERATURES INTO THE EXTENDED RANGES. THE EXTENDED RANGES WILL FEATURE AN AMPLIFIED BLOCKY UPPER AIR REGIME FROM THE ERN PACIFIC ACROSS THE CONUS INTO THE WRN ATLANTIC...WITH A STRONG UPPER HIGH/RIDGE CENTERED IN THE WRN U.S. AND DEEP TROF IN THE ERN U.S. A SERIES OF SHORT WAVES WILL DROP SSEWD DOWN THE BACKSIDE OF THE UPPER TROF AND IMPACT THE AREA ON SUNDAY AND TUESDAY REINFORCING THE "COOLER" AIR AND BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. GLASS && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1255 PM CDT TUE JUN 25 2013 ONCE AGAIN SCATTERED THUNDERSTORMS EXPECTED TO DEVELOP THIS AFTERNOON OVER PORTIONS OF THE FORECAST AREA. BEST CHANCES WILL BE OVER KUIN AND METRO AREA TAFS. TIMING AND COVERAGE STILL HARD TO PIN DOWN...SO JUST HAVE VCTS MENTION FOR NOW. WILL UPDATE AS NEEDED. OTHERWISE...GUSTY SOUTHWEST WINDS TO 25 KTS AT TIMES. WINDS AND STORMS TO DIMINISH EARLY THIS EVENING. THEN MCS DEVELOPMENT POSSIBLE OVER SOUTHEASTERN IOWA...SLIDING SOUTHEAST...PROBABLY SKIRTING KUIN. SO KEPT PROB30 MENTION FOR KUIN FROM 08Z TO 12Z WEDNESDAY. MAIN COLD FRONT TO SLIDE THROUGH ON WEDNESDAY. WINDS TO VEER TO THE WEST BY MID TO LATE MORNING...WITH STORMS POSSIBLE OVER METRO AREA AHEAD OF FRONT. SPECIFICS FOR KSTL...ONCE AGAIN SCATTERED THUNDERSTORMS EXPECTED TO DEVELOP THIS AFTERNOON OVER PORTIONS OF THE FORECAST AREA. BEST CHANCES WILL BE OVER KUIN AND METRO AREA TAFS. TIMING AND COVERAGE STILL HARD TO PIN DOWN...SO JUST HAVE VCTS MENTION FOR NOW. WILL UPDATE AS NEEDED. OTHERWISE...GUSTY SOUTHWEST WINDS TO 25 KTS AT TIMES. WINDS AND STORMS TO DIMINISH BY 01Z WEDNESDAY. MAIN COLD FRONT TO SLIDE THROUGH BY 17Z WEDNESDAY. WINDS TO VEER TO THE WEST...WITH STORMS POSSIBLE OVER METRO AREA WITH FRONT. BYRD && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1231 PM CDT Tue Jun 25 2013 .UPDATE... Issued at 1101 AM CDT TUE JUN 25 2013 Thunderstorm activity across eastern Kansas has persisted into the late morning hours, casting showers and cloud cover off to the northeast across our forecast area. While the intensity of the storms has come down over the past couple of hours, they also continue to regenerate on the back edge of the line; which appears due to strong moisture transport across central and eastern Kansas. Short range models other than the RUC are not picking up on this continued development at this time. Focusing on moisture transport, thoughts are that storms could keep redeveloping in eastern Kansas through noon, after which they should decay through the early afternoon as the focus for the transport moves north into eastern Nebraska and Iowa. Cast of showers and isolated embedded thunderstorms are all that is expected from this morning activity. Otherwise, looking at temperatures, have shaved a degree or two off the going highs for today as the cloud cover has been very persistent, but with some potential for the sun to come out by the early to mid-afternoon hours, thoughts are it will get hot and steamy fast. && .SHORT TERM...(Today through Thursday) Issued at 405 AM CDT TUE JUN 25 2013 Challenge for today continues to be chances of precipitation through this afternoon as a nocturnal MCS propagates across central Kansas this morning. The 00Z sounding from KTOP showed ample dry layer such that severe winds were reported with very little convection or rain associated. Upstream of that a short wave trough and low level jet...along with around 8 deg K/KM mid level lapse rates supported upscale growth of an MCS that is producing severe winds as well. This will be the area to monitor as it moves eastward towards the CWA. At this time the storm appears to be splitting with a southern area taking on a more discrete...almost super cellular mode. Given the 0-6km shear in EAX CWA of around 40kts...will have to monitor this activity closely for potential severe threat. The HRRR favors maintaining the area although weakening somewhat after sunrise. The surface winds ahead of this area are decent enough to believe that the boundary layer is well mixed even if the convection itself is elevated. The 500 mb flow will still be at least slightly cyclonic and with the low level moisture and associated CAPE values around 2000 J/KG along with weak short wave ripples in the flow...therefore a chance of convection will last through the day today. As the thermal ridge builds into the area though...the chances for precipitation will decrease with the increased heating of the column late this evening through the remainder of the short term. All models show the upper ridge significantly amplifying over the western half of the US by tomorrow afternoon...so as the nose of the thermal ridge edges into the area...we will have heat indices in the 103F to 106F range on Wednesday. Will not issue a headline at this time because if there is another MCS overnight...some debris cloudiness could limit the temperatures/heat indices. As the ridge amplifies to the west the flow will eventually turn more northwesterly so we will begin to see slight relief by Thursday. Given this flow and cap in place...precipitation chances decrease as well during Thursday. The exception is a possible MCS that may from over eastern Iowa and clip the northeast corner. .LONG TERM...(Friday through Monday) Issued at 405 AM CDT TUE JUN 25 2013 Northwest flow will prevail through this period as a the ridge/trough pattern amplifies across the CONUS. A weak front should have moved through the area by Friday morning with scattered convection lingering into the day. But the bigger effect of the front will be to cool dewpoints down into the lower 60s or even the 50s. As we see a great influence from the eastern trough, temperatures aloft cool down and thickness values decrease substantially. So will also see a nice cool down in the surface temperatures by Saturday into the first half of next week, temperatures look to very close to normal, with highs in the lower to middle 80s. And when combined with the much more comfortable dewpoints, it looks like we`ll see couple days of pleasant summer weather. With regards to precipitation chances, northwest flow is notoriously tricky for timing and placing precipitation chances. At this time, there isn`t a great signal to say that any certain period of time has a greater chance of precipitation than any other period of time. So instead of carrying some mention of precipitation through the bulk of the extended range, have trimmed POPs out until there is a better signal. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1229 PM CDT TUE JUN 25 2013 VFR conditions are expected to prevail at the terminals over the next 24 hours. What storms persist in the vicinity of the terminals this afternoon are expected to stay in the VFR category. Some potential for more storms to develop later, but confidence is not there to include in the TAF at this time. Otherwise, as the clouds slowly clear this afternoon surface winds will become rather gusty, with sustained speeds from the south above 12 knots, gusting above 25 knots, into the evening. Otherwise, look for winds to veer to the west overnight along with a decrease in speed. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ UPDATE...Cutter SHORT TERM...Adolphson LONG TERM...CDB AVIATION...Cutter
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
255 PM MDT Tue Jun 25 2013 .DISCUSSION... Tonight through Thursday...Southwest flow aloft continues to bring moisture and instability to the area. Convective activity is slow to develop this afternoon but a large plume of moisture is now moving into western Montana with scattered showers and thunderstorms developing. RUC analysis continues to show precipitation developing over the area this evening and development will be aided by a jet streak moving across the area. Have painted low pops across the county warning area until midnight. Any thunderstorms that develop will likely be high based with gusty winds being the main threat. Convective activity should generally end by midnight. Heights begin to rise Wednesday though isolated showers are possible in a swath across central Montana Wednesday morning due to the proximity of the jet streak. Heights continue to rise Wednesday afternoon through Thursday resulting in dry and warmer conditions. The strong westerly flow aloft Wednesday, combined with warmer temperatures, will allow the atmosphere to effectively mix down and gusty winds will result during the afternoon. Temperatures will be near seasonal averages Wednesday but will warm through the remainder of the week. Emanuel Thursday night through Tuesday...Medium range models remain in good agreement for the first few days of the forecast period. An upper level ridge over the western U.S. will strengthen over the northern Rockies for much warmer temperatures for Friday and Saturday. Model solutions diverge Saturday night as the GFS bring shortwave energy and an upper level jet through the northern Rockies for a slight chance of thunderstorms while the ECMWF keeps a dry and stable airmass in place. The upper wave depicted in the GFS will continue to affect central Montana through Sunday evening but the models come back into agreement by Monday as the ridge axis regresses into the Pacific northwest and puts Montana under a north to northwest flow aloft with unsettled but continued warm conditions into Tuesday. mpj && .AVIATION... Updated 1757Z. VFR conditions will prevail through the period. SCT low clouds viewed on satellite imagery and web cams at all terminals Tuesday afternoon. Strong southwest wind gusts up to 30kts will continue through evening. Winds will weaken overnight but then strengthen again Wednesday morning. A weak shortwave trough will bring scattered showers to southwest MT through 03Z this evening so have added VCSH to KBZN/KHLN. A weak frontal boundary moves through western MT early Wednesday around 26/15Z with low confidence for additional rainshowers near KGTF/KHLN/KLWT. Therefore, cigs are retained through the period but excluded Wednesday morning rain showers from the TAFS pending later guidance. Nutter && .PRELIMINARY POINT TEMPS/POPS... GTF 52 77 53 82 / 20 20 10 0 CTB 49 74 49 79 / 20 10 10 0 HLN 53 77 53 83 / 20 10 10 0 BZN 50 80 48 86 / 20 10 10 0 WEY 40 72 39 80 / 20 20 10 0 DLN 48 77 48 84 / 30 10 10 0 HVR 54 81 54 84 / 20 10 10 0 LWT 50 76 50 80 / 20 10 10 0 && .TFX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS BISMARCK ND
158 PM CDT TUE JUN 25 2013 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 200 PM CDT TUE JUN 25 2013 FORECAST HIGHLIGHTS IN THE SHORT TERM FORECAST PERIOD WILL BE STRONG TO SEVERE THUNDERSTORMS AND HEAVY RAIN POTENTIAL THROUGH THIS EVENING. CURRENTLY...WARM AND VERY HUMID DAY WITH DAYTIME HIGHS IN THE 80S AND SURFACE DEWPOINT TEMPS FROM 60 TO THE LOW 70S. LATEST RADAR IS VOID OF ECHOS OVER WEST AND CENTRAL NORTH DAKOTA AS OF 2 PM CDT. LATEST MODEL GUIDANCE SUGGESTS CONVECTIVE DEVELOPMENT NORTHWEST/NORTH CENTRAL EARLY THIS AFTERNOON...BUILDING SOUTH- SOUTHEAST LATE AFTERNOON-EARLY EVENING ALONG A SURFACE TROUGH IN PLACE FROM NORTHWEST NORTH DAKOTA THROUGH CENTRAL SOUTH DAKOTA. 17-18Z RAP SOUNDINGS WEAKEN/ERASE THE CAP BETWEEN 20-22Z ALONG THE SFC TROUGH AXIS. TRIGGER WILL BE A STRONG MID LEVEL S/WV PUSHING INTO WESTERN NORTH DAKOTA NOW...HELPING TO WEAKEN THE STRONG CAPPING INVERSION CURRENTLY IN PLACE. CONVECTION SHOULD THEN PUSH EAST THIS EVENING INTO THE OVERNIGHT WITH THE MID LEVEL WAVE AND SFC TROUGH. STRONG TO SEVERE WEATHER REMAINS IN PLAY WITH THE VERY STRONG INSTABILITY PRESENT...CURRENTLY 3-6K J/KG. LIMITING FACTOR WILL BE RATHER WEAK 0-6KM/EFFECTIVE SHEAR UP TO AROUND 20KTS CURRENTLY IN PLACE AND FORECAST THROUGH THIS EVENING. STILL...WITH THE AMOUNT OF CAPE PRESENT THERE IS A GOOD PROBABILITY OF LARGE SEVERE HAIL AND A DAMAGING WIND GUSTS. STORMS WILL BE WATER LOADED SO WILL LIKELY NEED A RATHER ROBUST/TALL UPDRAFT TO GET THE LARGE HAIL. IT DOES APPEAR THE MAIN THREAT TODAY INTO THIS EVENING WILL BE VERY HEAVY RAINFALL ELEVATING THE THREAT FOR FLASH FLOODING. CONVECTIVE CHANCES WILL END FROM WEST TO EAST THIS EVENING THROUGH WEDNESDAY MORNING AS FORCING PUSHES EASTWARD. OPTED TO KEEP WEDNESDAY AFTERNOON DRY FOR NOW ALONG WITH THE 12Z GFS/00Z ECMWF. THE 06Z AND 12Z NAM BOTH PAINTED LIGHT DIURNALLY DRIVEN QPF...SO WILL LET LATER SHIFTS TAKE A LOOK WITH ATTENTION FOCUSED ON THE NEXT 12 HOURS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 200 PM CDT TUE JUN 25 2013 THE MAIN FEATURE FOR THE EXTENDED PERIOD WILL BE THE INTENSIFYING UPPER LEVEL RIDGE OVER THE WESTERN US/CANADA AS FORECAST BY THE 12Z MODEL SUITE. WITH THE RIDGE AXIS POSITIONED OVER THE INTERMOUNTAIN WEST...NORTH TO NORTHWESTERLY FLOW WILL BE DOMINANT ACROSS NORTH DAKOTA FOR MUCH OF THE PERIOD. THIS WILL ALLOW FOR SEASONABLE TEMPERATURES...IN THE 80S TO CONTINUE...KEEPING THE AREA OUT THE WARMEST H850 TEMPERATURES THAT WILL DEVELOP ACROSS THE WESTERN US. OVERALL THE FORECAST WILL REMAIN DRY...HOWEVER THERE WILL BE PERIODIC CHANCES FOR PRECIPITATION FOR PARTS OF CENTRAL AND EASTERN NORTH DAKOTA...AS A FEW SHORTWAVES ROTATE AROUND THE WESTERN PERIPHERY OF THE UPPER LEVEL LOW POSITIONED OVER THE GREAT LAKES REGION. LATE THIS WEEKEND/EARLY NEXT WEEK...SOME UNCERTAINTY IS INTRODUCED INTO THE FORECAST AS THE THERE IS SOME DISAGREEMENT AMONGST THE 12Z LONG RANGE MODELS REGARDING THE POTENT SHORTWAVE THAT IS PROGGED TO DROP SOUTH FROM CANADA AND INTO THE NORTHERN PLAINS. DUE TO THIS UNCERTAINTY...WILL MAKE NO CHANGES TO THE ALLBLEND SOLUTION AT THIS TIME SINCE THERE IS NO TARGET OF OPPORTUNITY TO IMPROVE FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 200 PM CDT TUE JUN 25 2013 AREAS OF MVFR CU/STRATUS ACROSS WEST AND CENTRAL ND. OTHERWISE...THUNDERSTORMS ARE EXPECTED FOR MUCH OF NORTHERN AND CENTRAL NORTH DAKOTA THIS AFTERNOON AND EVENING. SOME STORMS MAY BE STRONG TO SEVERE. HAVE ADDED A TEMPO GROUP OF +TSRA FOR KMOT FROM 21-24 UTC GIVEN GOOD CONFIDENCE OF THUNDERSTORMS WITH HEAVY RAINFALL TO IMPACT THE TERMINAL. WILL UPDATE OTHER TERMINAL FORECASTS AS NEEDED. && .HYDROLOGY... ISSUED AT 200 PM CDT TUE JUN 25 2013 A FLASH FLOOD WATCH REMAINS IN EFFECT FOR NORTHWEST AND CENTRAL NORTH DAKOTA THROUGH THIS EVENING. VERY SLOW MOVING THUNDERSTORMS WITH INTENSE RAINFALL RATES ARE EXPECTED. ONE HOUR FLASH FLOOD GUIDANCE IS AROUND ONE TO ONE AND A HALF INCHES ACROSS MOST OF THE WATCH AREA. RAINFALL RATES WITH THUNDERSTORMS TODAY WILL EASILY SURPASS THIS THRESHOLD...AND WILL HAVE TO CLOSELY MONITOR FOR FLASH FLOODING THIS AFTERNOON AND EVENING. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 10 PM CDT /9 PM MDT/ THIS EVENING FOR NDZ001-002-009-010-017>020-034-042-045. FLASH FLOOD WATCH UNTIL 1 AM CDT WEDNESDAY FOR NDZ003>005- 011>013-021>023-025-035>037-046>048-050-051. && $$ SHORT TERM/HYDROLOGY...NH LONG TERM...LTH AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
101 PM CDT TUE JUN 25 2013 .UPDATE... ISSUED AT 100 PM CDT TUE JUN 25 2013 LOW LEVEL CLOUDS REMAIN ACROSS THE SOUTHERN RED RIVER VALLEY AND ARE TRYING TO ADVECT NORTHWARD. STILL THINKING THAT THESE SHOULD SCATTER AND WILL STICK WITH FORECASTED MAX TEMPS. DID INCREASE SKY COVER THROUGH THE AFTERNOON. SEVERE THREAT...WEAK DEEP LAYER SHEAR WILL LIKELY LEAD TO A LIMITED SEVERE THREAT. MODERATE INSTABILITY IN PLACE ACROSS THE WESTERN FA SHOULD LEAD TO A COUPLE SEVERE STORMS EARLY THIS EVENING. HRRR AND 4KM-WRF MODELS INDICATING THAT A SEVERE THUNDERSTORM WIND THREAT MAY PERSIST UNTIL MIDNIGHT FOR EASTERN NORTH DAKOTA. HEAVY RAIN THREAT...VERY SLOW STORM MOTION COMBINED WITH PWATS AOA 1.5 INCHES WILL LEAD TO AN INCREASED HEAVY RAIN THREAT. HOWEVER...COVERAGE OF THE STORMS SHOULD DECREASE AS THE STORMS MOVE THROUGH EASTERN NORTH DAKOTA (CONSIDERING TIMING WILL BE NEAR AND AFTER SUNSET). INCOMING HI-RES MODELS DEVELOP SLOW MOVING STORMS ACROSS WEST CENTRAL NORTH DAKOTA...WITH THE THUNDERSTORM AREA BECOMING MORE PROGRESSIVE AS IT BECOMES MORE OF A SEVERE WIND THREAT. WILL CONTINUE TO MONITOR...BUT EXPECTED AREAL COVERAGE OF HEAVY RAIN NOT ENOUGH FOR A FLASH FLOOD WATCH. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 330 AM CDT TUE JUN 25 2013 THE MAIN CHALLENGE WILL BE SHOWERS AND THUNDERSTORM POTENTIAL LATER THIS AFTERNOON INTO WED. MODELS ARE IN DECENT AGREEMENT OVERALL...AND PREFER THE SLIGHTLY SLOWER GFS/WRF FOR THE EVOLUTION OF CONVECTION LATER THIS AFTERNOON AND TONIGHT. FOR TODAY...THE MORNING SHOULD REMAIN DRY FOR ALL AREAS AS A SHORTWAVE AND SFC BOUNDARY MOVE INTO CENTRAL ND. THERE SHOULD BE SHOWERS AND STORMS DEVELOPING IN OUR WESTERN AREAS LATE IN THE DAY...WITH MOST AREAS REMAINING DRY AND WARM THROUGH 00Z WED. FOR TONIGHT...EXPECT SHOWERS AND STORMS TO MOVE SLOWLY FROM WEST TO EAST. PRECIPITABLE WATERS INCREASE TO OVER 1.5 INCHES IN ALL AREAS AROUND 06Z...WITH A SHORTWAVE TROUGH AND WEAK SFC BOUNDARY. THERE IS NOT A STRONG OR FOCUSED LOW LEVEL JET THOUGH...SO THIS COULD PRECLUDE A MORE ORGANIZED MCS FROM FORMING. IN ADDITION...DEEP LAYERED SHEAR VALUES ARE WEAK...ONLY AROUND 15KT. INSTABILITY WILL BE FAIRLY HIGH AT LEAST THIS EVENING IN THE WEST WITH MLCAPE AROUND 2000 J/KG. THE CURRENT THINKING IS A BROKEN LINE OF STORMS WILL AFFECT THE WESTERN AREAS BY EVENING...THEN MOVE INTO THE VALLEY AROUND 06Z THEN INTO THE EAST THEREAFTER. THE MAIN THREAT SHOULD BE LOCALLY HEAVY RAINFALL GIVEN THE HIGH PWATS AND SLOW MOVEMENT OF STORMS WITH WEAK WINDS ALOFT. CAN/T RULE OUT A SEVERE STORM OR TWO...MAINLY IN THE WEST THIS EVENING...WITH HAIL AND WIND THE MAIN THREATS. THERE COULD BE SOME LOCALIZED FLOODING ISSUES WHERE STORMS DEVELOP...SO THIS WILL HAVE TO BE MONITORED. FOR NOW WON/T ISSUE A FLASH FLOOD WATCH...BUT THIS IS SOMETHING TO CONSIDER AS WE HEAD THROUGH TODAY. WE WILL MENTION HEAVY RAIN IN THE GRIDS/HWO IN ALL AREAS TONIGHT. ON WEDNESDAY...THE BEST CHANCE FOR SHOWERS AND STORMS SHOULD MOVE INTO OUR MN COUNTIES. THE LATEST MODEL TRENDS ARE FOR A SLOWER MOVEMENT TO THE EAST THOUGH...SO THERE COULD BE SOME CONVECTION ALONG AND EAST OF THE VALLEY THROUGH AT LEAST EARLY AFTERNOON WITH INSTABILITY REMAINING. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 330 AM CDT TUE JUN 25 2013 FOR WED NIGHT...EXPECT THE THREAT FOR SHOWERS AND STORMS EARLY IN THE NORTHEAST BEFORE DRIER AIR MOVES IN AFTER 06Z THU. ON THURSDAY...THE MORNING SHOULD BE DRY WITH INCREASING NW WINDS BY AFTERNOON. IT SHOULD BECOME BREEZY TO PERHAPS WINDY IN MOST AREAS WITH ABOUT 30KT TO MIX AND ADIABATIC SOUNDINGS TO 750MB. BY AFTERNOON...SOME WEAK INSTABILITY IS POSSIBLE IN THE NORTHEAST WITH SOME LINGERING CYCLONIC FLOW...SO WILL MENTION A LOW CHANCE FOR SOME SHOWERS AND STORMS HERE. TEMPS SHOULD WARM ABOVE NORMAL WITH MILD MID LEVEL TEMPS. FOR FRIDAY THROUGH MONDAY NIGHT...A LONGWAVE SYNOPTIC PATTERN WILL REMAIN. EXPECT A FAIRLY STABLE FRIDAY THROUGH NEXT WEEKEND WITH THE GFS/ECMWF/GEM/DGEX ALL SHOWING A HIGHLY AMPLIFIED RIDGE ACROSS THE WESTERN CONUS AND A DEEP TROUGH PARKED OVER THE OHIO RIVER VALLEY. AS A RESULT...THE NORTHERN PLAINS WILL BE UNDER THE INFLUENCE OF NORTHWEST FLOW ALOFT. TIMING AND PLACEMENT OF WEAK SHORT-WAVES IN THIS FLOW IS DIFFICULT...SO WILL FOLLOW ALL BLEND 20 POPS FOR MOST PERIODS. TEMPERATURES WILL BE NEAR SEASONAL NORMALS WITH HIGHS IN THE UPPER 70S TO LOWER 80S AND LOWS IN THE UPPER 50S TO LOWER 60S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 100 PM CDT TUE JUN 25 2013 AREA OF MVFR CIGS WILL PERSIST ACROSS SERN ND INTO WCNTRL MN THROUGH EARLY AFTERNOON...BECOMING SCATTERED TO BKN IN THE MID AFTERNOON. AREAS OF SHOWERS AND EMBEDDED TSTMS WITH MVFR CIGS AND VSBYS WILL DEVELOP THROUGH WESTERN AND CENTRAL ND IN THE LATE AFTERNOON. THESE WILL MOVE INTO EASTERN ND THROUGH THE EARLY EVENING...AND CROSS THE RRV INTIO NWRN MN IN THE LATE EVENING. && .HYDROLOGY... ISSUED AT 100 PM CDT TUE JUN 25 2013 THE RED RIVER AT WAHPETON HAS CRESTED AND THE RIVER LEVEL HAS RECEDED BACK TO MINOR FLOOD STAGE. THE SHEYENNE AT HARWOOD WILL EASE BELOW FLOOD STAGE THIS AFTERNOON. OTHERWISE...MINOR FLOODING CONTINUES AT FARGO...SABIN... DILWORTH AND WEST FARGO. SOME LOCALIZED HEAVY RAINFALL IS POSSIBLE TONIGHT...WHICH COULD IMPACT RIVER STAGES IF IT FALLS OVER ALREADY SWOLLEN RIVERS IN THE SOUTHERN RED RIVER VALLEY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...DK LONG TERM...DK/ROGERS AVIATION...GUST HYDROLOGY...WJB
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
152 PM EDT TUE JUN 25 2013 .SYNOPSIS... DISTURBANCES EMBEDDED IN WESTERLY FLOW ALOFT WILL INTERACT WITH A WARM AND UNSTABLE AIRMASS TO PROVIDE CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS THE OHIO VALLEY THROUGH MID WEEK. THE GREATEST PRECIPITATION CHANCES WILL BE ON WEDNESDAY NIGHT...AS A COLD FRONT APPROACHES THE REGION. SLIGHTLY DRIER AND SLIGHTLY COOLER CONDITIONS ARE EXPECTED BY THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SATELLITE IMAGERY INDICATES CUMULUS DEVELOPING ACROSS MOST OF THE FORECAST AREA. THIS FIELD LOOKS A LITTLE MORE ROBUST IN CENTRAL OHIO SOUTH OF AN OLD OUTFLOW BOUNDARY. SO IT APPEARS THAT COULD BE THE AREA WHERE INITIAL STORMS DEVELOP OVER THE NEXT FEW HOURS. HRRR AND RAP HAVE BEEN SUGGESTING THAT ISOLATED TO SCATTERED CELLS WILL DEVELOP ALONG A NORTHEAST TO SOUTHWEST LINE...ROUGHLY NEAR THE I-71 CORRIDOR...BY MID AFTERNOON AND THEN MOVE OFF TO THE EAST BY LATE AFTERNOON. THERE WILL BE ENOUGH INSTABILITY TO ALLOW FOR SOME STRONGER STORMS. GIVEN TEMPERATURE TRENDS HAVE BUMPED UP HIGHS SLIGHTLY IN MOST PLACES. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... THE PRIMARY FOCUS FOR THE SHORT TERM WILL BE ON CONVECTION AHEAD OF A SHORTWAVE AND COLD FRONT ON WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT. WEAK RIDGING OVER THE ILN CWA TONIGHT WILL BE UNLIKELY TO FAVOR NOCTURNAL CONVECTIVE DEVELOPMENT...WITH LLJ FORCING SETTING UP TO THE WEST. THOUGH A FEW CONVECTIVE ALLOWING MODELS DO SHOW UPSTREAM CONVECTION COMING INTO THE CWA (WHICH DOES SEEM REASONABLE GIVEN LINGERING INSTABILITY)...POPS WILL BE KEPT SOMEWHAT LOW DURING THE DIURNAL MIN (30 NW / 20 SE). ON WEDNESDAY...SOUTHWESTERLY FLOW OVER THE ILN CWA WILL INCREASE...AS MOISTURE TRANSPORT BEGINS TO RAMP UP JUST WEST OF THE CWA. A SHORTWAVE AND ASSOCIATED SURFACE LOW WILL BE MOVING ACROSS THE SOUTHERN GREAT LAKES. THE FORCING AHEAD OF THE SHORTWAVE SEEMS TO BE A BIT AHEAD OF THE ILL-DEFINED COLD FRONT TRAILING THE SURFACE LOW (WHICH WILL NOT LIKELY CROSS THE CWA UNTIL THURSDAY MORNING). THE OVERALL MODEL TREND SEEMS TO ALLOW FOR A SLIGHTLY QUICKER PASSAGE OF THE SHORTWAVE (WEDNESDAY AFTERNOON INTO WEDNESDAY OVERNIGHT) THAN IN PREVIOUS FORECASTS. WITH THIS FORECAST INCORPORATING THE PRESENCE (FINALLY) OF SOME WELL-DEFINED FORCING...AND EXPECTED UNSTABLE CONDITIONS (1500-2000 J/KG...PERHAPS UP TO 3000 J/KG IF UNINHIBITED BY CLOUDS OR PRECIPITATION DURING THE DAY)...LIKELY POPS HAVE BEEN INCLUDED FOR THE ENTIRE CWA. OF GREATER CONCERN IS THE INCREASING DYNAMICS WITH THE SYSTEM...AS WNW FLOW ALOFT COMBINES WITH A STRENGTHENING BAND OF LOW-LEVEL SOUTHWESTERLY FLOW TO CREATE A SHEARED ENVIRONMENT FAVORABLE FOR STORM ORGANIZATION. TOUGH TO RULE OUT ANY PARTICULAR TYPES OR MODES OF SEVERE WEATHER AT THIS POINT...AS THERE DOES APPEAR TO BE POTENTIAL FOR QUITE A BIT MORE THAN JUST THE RUN-OF-THE-MILL STRONG TO MARGINALLY SEVERE CONVECTION OF THE PAST FEW DAYS. THE HWO WORDING WILL BE REFINED A BIT FOR THIS THREAT...WHICH MAY CONTINUE INTO THE OVERNIGHT HOURS WEDNESDAY NIGHT. SEEING SOME HYDRO PARAMETERS LIGHT UP A BIT AS WELL (PWAT WELL OVER 1.50" AND GOOD MOISTURE TRANSPORT AHEAD OF THE SHORTWAVE). THOUGH STORM ELEMENTS SHOULD BE SOMEWHAT PROGRESSIVE...SOME HEAVY RAIN WILL BE POSSIBLE. ANOTHER SHORTWAVE WILL IMPACT THE ILN CWA THURSDAY...THOUGH THE FORCING AHEAD OF THE MEAN TROUGH WILL GENERALLY BE EAST OF THE CWA. COOLING TEMPS ALOFT WILL HELP PROVIDE SOME INSTABILITY...SO CONVECTIVE CHANCES AGAIN EXIST THURSDAY (HIGHEST IN THE EASTERN CWA). IN THE WNW FLOW...PROBABLY NOT SAFE TO RULE OUT ADDITIONAL DEVELOPMENT FRIDAY...THOUGH NO STRONG SIGNALS FOR ORGANIZATION ARE PRESENT. TEMPS WILL BEGIN TO DROP SLIGHTLY AFTER THE FRONTAL PASSAGE THURSDAY MORNING. THE WARMEST DAY WILL BE WEDNESDAY...WITH MAX TEMPS AROUND 90 (A SOMEWHAT UNCERTAIN FORECAST GIVEN THE POSSIBILITY OF CLOUDS AND CONVECTION)...AND DEWPOINTS GETTING TO AROUND 70 OR EVEN THE LOWER 70S. HEAT INDICES WEDNESDAY SHOULD MAKE IT TO THE MID 90S...SHY OF ADVISORY CRITERIA BY SEVERAL DEGREES. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... BUILDING RIDGE OVER THE WESTERN UNITED STATES WILL CONTINUE TO CARVE OUT A TROUGH ACROSS THE EAST THROUGH THE REMAINDER OF THE LONG TERM PERIOD. THIS WILL KEEP TEMPERATURES FAIRLY SEASONABLE FRIDAY THROUGH MONDAY WITH HIGHS GENERALLY IN THE LOWER 80S. MODELS ARE SHOWING VARIOUS WEAK SHORT WAVES PROGRESSING THROUGH THE TROUGH BUT IT IS TOUGH TO PINPOINT ANY KIND OF TIMING. AS A RESULT...WITH THE UPPER LEVEL TROUGH IN PLACE AND GIVEN THE TIME OF YEAR...THINK THE BEST WAY TO GO IS TO TREND THE POPS DIURNAL BUT KEEP THEM ON THE LOW SIDE THROUGH THE WEEKEND. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 1750Z...ISOLATED SHOWERS AND THUNDERSTORMS ARE BEGINNING TO DEVELOP IN THE VICINITY OF AN OLD OUTFLOW BOUNDARY WHICH HAS BEEN SINKING SOUTHWARD ACROSS CENTRAL OHIO. NEAR-TERM HIGH RESOLUTION MODEL GUIDANCE SUGGESTS ACTIVITY WILL INCREASE THROUGH THE REMAINDER OF THE AFTERNOON IN A WARM AND UNSTABLE AIR MASS. HOWEVER WITH COVERAGE APPEARING SOMEWHAT SCATTERED...HAVE LEFT A VCTS IN THE TAFS SINCE THERE IS NO DEFINITIVE TIMING. DELAYED THE START OF THE VCTS AT THE CINCINNATI SITES SINCE ACTIVITY WILL HAVE TO PROPAGATE SOUTHEASTWARD...AND THERE IS SOME POSSIBILITY THAT MOST OF THE STORMS COULD BE TO THE EAST. IF A STORM DIRECTLY AFFECTS A TERMINAL...THEN BRIEF MVFR OR IFR CONDITIONS AND GUSTY WINDS COULD BE POSSIBLE. THIS ACTIVITY SHOULD DIE DOWN WITH LOSS OF DAYTIME HEATING THIS EVENING. THERE ARE NOW SEVERAL MODELS SUGGESTING A SECOND ROUND OF STORMS TIED TO AN UPPER LEVEL DISTURBANCE THAT MAY ENTER THE AREA AS A LINE OR CLUSTERS OF STORMS IN THE 04-08Z TIME FRAME. HOWEVER GIVEN THE UNCERTAINTY...JUST ADDED A VCTS AT THIS TIME. AFTERWARD THERE IS A LOW ENOUGH CHANCE OF PRECIPITATION TO KEEP THE TAFS DRY THROUGH WEDNESDAY MORNING...ALTHOUGH WINDS WILL BEGIN GUSTING NEAR 20KT BY MIDDAY. IN THE KCVG EXTENDED TAF...THUNDERSTORMS CAN BE EXPECTED TO INCREASE IN COVERAGE LATE WEDNESDAY AFTERNOON. OUTLOOK...THUNDERSTORMS LIKELY FROM WEDNESDAY AFTERNOON THROUGH THURSDAY. THUNDERSTORMS POSSIBLE...MAINLY AFTERNOON AND EVENING...FRIDAY AND SATURDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...HATZOS NEAR TERM... SHORT TERM...HATZOS LONG TERM...JGL AVIATION...SNYDER
AREA FORECAST DISCUSSION
NWS SPOKANE WA
203 PM PDT Tue Jun 25 2013 .SYNOPSIS... A wet pattern continues across the Inland Northwest through mid week, with occasional showers and the potential for thunderstorms. The latter half of the week, into early next week, will be dramatically different. Expect a quick warming, drying trend with temperatures moving to above normal, summer like values. && .DISCUSSION... Tonight: The upper level shortwave that moved through the Columbia Basin early today is now pivoting across the ID Panhandle and into the Northeast Mountains. This disturbance is expected to push north of the region by the evening hours; however, there is another weaker disturbance set to move in behind this wave for late this afternoon into the late evening hours. Models show some weak upper level instability ahead of this next wave. The best instability looks to be from the Northeast Mountains to the Central Panhandle Mountains and points southeastward, as well as northwest of a line from Moses Lake to Sandpoint. These are the two areas that HRRR focuses showers for this evening into the early portions of tonight. There does not appear to be enough instability for thunderstorms once we lose our surface heating, but we should continue to see isolated to scattered thunderstorms across much of the Panhandle into the early evening hours (especially from the Northeast Blue Mountains into the Central Panhandle Mountains). These thunderstorms will be capable of heavy rain possibly mixed in with some small hail and gusty outflow winds. We will also see a little bit of clearing behind this next wave with a narrow dry slot showing up on the water vapor satellite imagery. With dew point temps remaining in the low 50s, it will not take much cooling for fog to redevelop in the valleys of extreme eastern WA and the ID Panhandle late tonight into early Wednesday morning, especially across the mountain valleys. /SVH Wednesday through Friday night: Expect lingering shower chances, especially in the afternoon and early evening hours, before a ridge of high pressure begins to build over the West by the end of the work week. Between Wednesday and Thursday evening the jet stream bisecting the Inland Northwest slowly migrates north. Impulses/vorticity maxima littering the west-southwest flow ride through on this jet, keeping the shower chances alive. The precise timing and track of individual impulses is not agreed upon, decreasing confidence in what areas have the overall best chance of showers. On Wednesday loose model agreement places the highest concentration around the mountains, though all areas will have at least slight chances through the evening. Coverage decreases through Wednesday evening and the overnight, with the main chances retreating to the Cascades and eastern mountains. By Thursday afternoon the threat of showers increases again. However with the jet starting to lift north through this period the overall threat will be less as compared to Wednesday. The threat of thunderstorms is not all that great given depicted convective instability. But a few cannot be ruled out across the northern-tier, largely north of Highway 2, as well a across the Blue Mountains through central Panhandle Mountains during the afternoon/early evening hours. By Thursday night into Friday night the ridge begins to amplify over the region from the south to southeast and the jet axis lifts north through B.C., leading to an overall drying trend. A few models still keep a slight risk of showers going near the Cascades and near the Canadian border, as well as closer to the Blue Mountains, for Friday afternoon but the overall risk is too small at this time to put a mention in the official forecast. This should also be the beginning of the more pronounced warming trend. Regional 850mb temperatures warm into the upper teens to lower 20s. This supports highs about 10 degrees above normal. /J. Cote` Saturday through Tuesday: This period will be hot and dry. The region will under a ridging pattern from the high pressure located in the Southwest US. The strength of the ridge will keep a Low off the NW Pacific Coast from coming onshore. Temperatures in the region are expected to be 10 to 15 degrees above normal. Most places will see the high temperatures into 80s to 90s with a few places possibly reaching 100. On Saturday, the mid level moisture mixed with the high temperatures could produce an isolated thunderstorm in the high elevations of the mountains. As drier conditions continue through the weekend, the chances for these storms diminishes. /JDC && .AVIATION... 18Z TAFS: A potent compact shortwave trough of low pressure is moving to the north and east across the basin late this morning. This shortwave has produced a line of heavy rain showers with embedded thunderstorms from KPUW into the northern portions of the Upper Columbia Basin. This convective line will move into the Spokane/Coeur d`Alene Areas between 11:30 AM and 2:00 PM today. Frequent cloud to ground lightning strikes, gusty outflow winds and heavy rain is expected with these storms. The heavy rain will likely drop cigs and vis into MVFR/IFR category for a period of 30 minutes to an hour. Showers and thunderstorms will continue to be possible behind this convective line through the early evening hours with the best chances of additional thunderstorms expected at the KLWS and KPUW taf sites. /SVH && .PRELIMINARY POINT TEMPS/POPS... Spokane 51 71 54 78 57 87 / 40 40 20 20 0 0 Coeur d`Alene 51 70 53 78 54 86 / 30 40 30 20 0 0 Pullman 52 72 52 79 54 85 / 80 40 30 10 0 0 Lewiston 57 80 59 88 61 93 / 80 40 20 10 0 0 Colville 51 73 51 82 52 90 / 60 40 20 20 10 0 Sandpoint 50 69 50 77 50 87 / 60 50 20 20 10 0 Kellogg 49 67 51 76 55 90 / 60 50 30 20 0 0 Moses Lake 55 77 58 86 60 90 / 40 20 10 10 0 0 Wenatchee 55 76 60 83 63 88 / 50 20 10 10 0 0 Omak 51 74 54 82 57 89 / 70 30 20 20 10 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
339 PM CDT TUE JUN 25 2013 .VERY SHORT TERM...TONIGHT AND WEDNESDAY. TONIGHT - CONFIDENCE...LOW MAIN CHALLENGE CENTERS ON CONVECTIVE TRENDS AS HAS BEEN THE CASE THE LAST SEVERAL DAYS. AIR MASS DESTABILIZATION UNDERWAY WITH -11 LI/S INTO SW CWA. CORRIDOR OF HIGH ML CAPE VALUES ALSO LOCATED THERE AS WELL...WITH VALUES AS HIGH AS 3500 J/KG. SPC MONITORING FOR A WATCH WITH BORDERLINE 30-35 KNOT 0-6 KM BULK SHEAR. WATER VAPOR/RUC SHOWING A WEAK RIPPLE ACROSS SRN MN/NRN IA...MAY BE ENOUGH TO ENHANCE THE ALREADY DEVELOPING CONVECTION NEAR KDBQ. AIR MASS IS BECOMING INCREASINGLY MOIST AND UNSTABLE. 3 HOUR ML CAPE CHANGE AROUND 1500 J/KG INTO THE SW CWA. DEEP LAYER MOISTURE FLUX CONVERGENCE ALSO MAXIMIZED IN A CORRIDOR FROM NRN IL INTO SW WI. SUPERCELL COMPOSITE MAXIMIZED SOUTH OF MADISON...THOUGH DRIVEN LARGELY BY THE VERY HIGH CAPE VALUES. LATEST HRRR BLOWS UP THIS AREA IN SW WI AND SPREADS IT ACROSS CWA THROUGH 01Z. LATER IN THE NIGHT LOW LEVEL JET NOSE DISPLACED FURTHER SOUTH AND EAST AND HRRR BLOSSOMS THINGS ACROSS IOWA AND THIS WOULD THEN HEAD SOUTHEAST...POSSIBLY GRAZING FAR SRN WI. SURFACE FLOW IS ADVECTING 70 PLUS DEW POINT AIR INTO SRN WI. MODELS IN DECENT AGREEMENT IN BRINGING A VORT MAX INTO IOWA AND TO JUST SOUTH OF WI BY 12Z. VORTICITY ADVECTION WITH THIS FEATURE BRINGS BEST FORCING TO SW CWA AROUND 6Z AND SPREADS IT ACROSS THE REST OF THE AREA BETWEEN 6-12Z. AT THIS POINT TEND TO SIDE WITH THE MODELS SHOWING TSRA AFFECTING THE CWA TONIGHT...ESPECIALLY THE SW 1/2...WITHIN AND NEAR THE LI/CAPE GRADIENTS IN CONJUNCTION WITH THE APPROACHING UPPER FEATURE. THE NAM AND SOME OF THE OTHER MESO MODELS SHOW NEXT TO NOTHING WHICH IS A CONCERN IF THE 850 LEANS FURTHER SOUTH. FOR NOW WILL RETAIN THE HEFTY POPS WE HAVE GOING AND HANG ONTO THE FLASH FLOOD WATCH. WEDNESDAY - CONFIDENCE...MEDIUM INFLUENCE OF THE 500 MILLIBAR WAVE SHIFTS EAST BY THE AFTERNOON AND PER SWODY1 THE REAL FOCUS FOR THE HEFTY ACTIVITY SHIFTS INTO OH VALLEY. PROGS SHOW BEST QPF IN THE MORNING WITH BETTER CWASP NUMBERS INTO THE OHIO VALLEY. HOWEVER STILL SOME LINGERING TROUGHINESS SO WILL KEEP POPS GOING INTO THE AFTERNOON. BUT ALL IN ALL THE 850 JET INFLUENCE AND UPPER FORCING SHIFTS TO OUR SOUTH AND EAST EARLY IN THE DAY. .SHORT TERM...WEDNESDAY NIGHT THROUGH FRIDAY. WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE MEDIUM. SHORT WAVE TROUGH MOVES OFF TO THE EAST WITH BETTER FORCING STAYING MORE CLOSELY TIED TO THE VORT MAX/PV ANOMALY PASSING NE OF FORECAST AREA WEDNESDAY NIGHT...WELL REFLECTED IN LAYER Q-VECTOR CONVERGENCE AND ISENTROPIC OMEGA. HOWEVER LOW-LEVEL MOISTURE CONVERGENCE MOVES ACROSS CWA WITH WEAK SURFACE TROUGH WITH LINGERING INSTABILITY IN THE EVENING TO KEEP A CHANCE OF THUNDERSTORMS...TAPERING TO A SLIGHT CHANCE OVERNIGHT. HAVE CHANCE POPS THURSDAY AFTERNOON AS ANOTHER VORT MAX DROPS SE THROUGH THE STATE...WITH SLIGHTLY STEEPENING MID-LEVEL LAPSE RATES LEADING TO PEAK HEAT OF THE DAY INSTABILITY. THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE LOW TO MEDIUM. 300 MB SPEED MAX BRINGS A SHORT WAVE TROUGH OF VARYING STRENGTH DEPENDING ON MODEL INTO THE REGION WITH DCVA-DRIVEN PCPN REACHING THE NORTH THURSDAY NIGHT WITH THE BETTER CHANCE ACROSS THE REST OF THE CWA FRIDAY. .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. FORECAST CONFIDENCE LOW. UNSETTLED PERIOD WITH UPPER TROUGH NOW RETROGRADING FARTHER WEST THAN PREVIOUS DAYS AND SETTLING OVER THE WESTERN GREAT LAKES THROUGH THE REMAINDER OF THE PERIOD. GFS HAS A DRIER LOOK THAN ECMWF AS IT DIGS AN OPEN WAVE WHILE ECMWF KEEPS A CLOSED LOW RIGHT OVER THE STATE. WE MAY BE GETTING RID OF THE HEAVY RAINS/SEVERE WITH THE EXIT OF THE MOIST AIR MASS...BUT ENOUGH INSTABILITY AND WEAK FORCING WITH VORT MAXES MOVING THROUGH THE TROUGH TO KEEP AT LEAST SLIGHT CHANCES IN FOR MUCH OF THE EXTENDED...THOUGH BLENDED GUIDANCE BRINGS LESSER CHANCES IN FOR EARLY NEXT WEEK. AT OR BELOW NORMAL TEMPERATURES ARE EXPECTED. && .AVIATION/00Z TAFS/...AS HAS BEEN THE CASE THE LAST COUPLE OF DAYS CEILINGS/VSBYS WILL BE DRIVEN BY CONVECTIVE EVENTS. EXPECTING ADDITIONAL DEVELOPMENT AS THE NIGHT WEARS ALONG. 500 MILLIBAR SHORTWAVE APPROACHES AND INTERACTS WITH INCREASINGLY UNSTABLE AIRMASS. INFLUENCE OF THIS SHORTWAVE WILL CONTINUE INTO WEDNESDAY MORNING...BEFORE BEST FORCING SHIFTS INTO THE OHIO VALLEY. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR WIZ046-047-056- 057-062-063-067>070. LM...NONE. && $$ TONIGHT/WEDNESDAY AND AVIATION/MARINE...COLLAR WEDNESDAY NIGHT THROUGH TUESDAY...REM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND WEDNESDAY ISSUED AT 255 PM CDT TUE JUN 25 2013 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW EARLIER CONVECTION ACROSS IOWA AND SOUTHERN WISCONSIN DISSIPATED/EXITED EARLIER THIS AFTERNOON. TOUGH TO TELL WHERE THE OUTFLOW BOUNDARY STALLED OUT...BUT AN ARCING LINE OF CLOUDS FROM NW IOWA TO MOLINE TO NW OHIO COULD BE IT. REMNANT SHORTWAVE MOVING ACROSS SOUTHERN MINNESOTA AND IOWA IS RELATIVE INACTIVE SO FAR THIS AFTERNOON...AS IS MUCH OF THE STATE OF WISCONSIN. A FEW STORMS POPPED UP OVER SOUTHERN WISCONSIN AND ALSO WILL NEED TO WATCH THE AREA OF CU OVER NORTHERN WISCONSIN FOR SHOWER/TSTORM DEVELOP LATER THIS AFTERNOON. ML CAPES ARE BUILDING TO AROUND 800 J/KG BUT NEED A LITTLE MORE LIFT VIA LAKE BREEZES TO GET CONVECTION STARTED. AN AREA OVER FAR NORTHERN WISCONSIN MIXED OUT...SO WILL SHIFT PRECIP CHANCES MAINLY SOUTH OF VILAS COUNTY. THE NEXT AREA OF WEATHER IS MOVING ACROSS THE PLAINS WHICH WILL ARRIVE TOMORROW. PRECIP CHANCES CONTINUE TO BE THE MAIN FORECAST CONCERNS. TONIGHT...WILL KEEP AN ISOLATED MENTIONED OF THUNDERSTORMS OVER CENTRAL WISCONSIN AS WELL AS NORTHERN WISCONSIN UNTIL DIURNAL INSTABILITY DIMINISHES. BY MID TO LATE EVENING...A LLJ WILL GET CRANKING OVER THE CENTRAL PLAINS AHEAD OF THE NEXT LOW PRESSURE SYSTEM. THE NAM/GFS/ECMWF ALL SUGGEST THAT THE NOSE OF THE LLJ WILL POINT TOWARDS NORTHERN IOWA/SOUTHERN WISCONSIN/NORTHERN ILLINOIS...WHICH IS THE REGION THAT HAS BEEN LIGHTING UP WITH STORMS EACH OF THE PAST SEVERAL NIGHTS. DO NOT HAVE ANY REASON TO THINK DIFFERENTLY THIS TIME...BUT DO HAVE WEAK ISENTROPIC ASCENT OCCURRING OVER CENTRAL WISCONSIN THIS EVENING...THAT MOVES INTO NORTH-CENTRAL AND EAST-CENTRAL WISCONSIN OVERNIGHT. WILL KEEP A SMALL CHANCE OF STORMS OVERNIGHT. ANY SEVERE THREAT LOOKS TO REMAIN TO THE SOUTH HOWEVER. ANOTHER MUGGY NIGHT WITH LOWS IN THE 60S. WEDNESDAY...LOW PRESSURE OVER THE NORTHERN MISSISSIPPI VALLEY AT THE START OF THE PERIOD WILL SHIFT SLOWLY EAST INTO WISCONSIN. MODELS HAVE SLOWED DOWN THE PROGRESSION OF THIS LOW SOMEWHAT...SO WILL DELAY THE LIKELY POPS UNTIL THE AFTERNOON. EVEN WITH THE SLOWER ARRIVAL...AM ANTICIPATING PLENTY OF CLOUD COVER WHICH SHOULD REDUCE SURFACE HEATING AND INSTABILITY. A SEVERE THREAT SEEMS TO LOW TO MENTION AT THIS TIME THOUGH ANY STORMS COULD PRODUCE LOCALLY HEAVY RAINFALL. .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY ISSUED AT 255 PM CDT TUE JUN 25 2013 WHILE THE UPPER LEVEL WINDS ARE EXPECTED TO BECOME NORTHWEST THURSDAY WHILE THE UPPER RIDGE BUILDS OVER THE WESTERN STATES...IT WILL TAKE A WHILE BEFORE WE GET THE DRY WEATHER USUALLY ASSOCIATED WITH NORTHWEST UPPER FLOW. THE REASON IS THAT SEVERAL JET STREAKS ARE FORECAST TO ROTATE AROUND THE UPPER RIDGE AND DIVE INTO THE GREAT LAKES TROUGH. THIS RESULTS IN THE FORMATION OF AN ELONGATED UPPER TROUGH OR LOW OVER THE GREAT LAKES. SEVERAL UPPER JETS SHOULD PROVIDE UPPER SUPPORT FOR PRECIPITATION AT TIMES WHILE THERE IS RESIDUAL LOW LEVEL MOISTURE. SUNDAY AND MONDAY LOOK TO BE THE DAYS WITH THE LEAST CHANCE OF RAIN ALONG WITH COOL TEMPERATURES AND LOW DEW POINTS. LOOKS LIKE A WEAK UPPER LEVEL LOW CONTINUES ACROSS THE AREA THROUGH THE MIDDLE OF NEXT WEEK THOUGH THERE IS SOME INDICATION THAT IT WILL BEGIN TO EXIT ON INDEPENDENCE DAY. NOT MUCH CONFIDENCE IN THE UPPER PATTERN THOUGH. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1240 PM CDT TUE JUN 25 2013 SHOWERS AND THUNDERSTORMS OVER IOWA AND SOUTHERN WISCONSIN HAS PUSHED A RAIN COOLED BOUNDARY WELL SOUTH OF THE REGION. MEANWHILE...A LAKE SUPERIOR ENHANCED COLD FRONT WILL SETTLE ACROSS NORTHERN WISCONSIN THIS AFTERNOON. THIS COLD FRONT MAY GENERATE SCT SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON BEFORE DIMINISHING EARLY THIS EVENING. COVERAGE IS UNCERTAIN SO WILL LEAVE OUT OF THE RHI TAF. THEN THE BOUNDARY OVER IOWA AND NORTHERN ILLINOIS WILL RETURN NORTH TONIGHT AHEAD OF A LOW PRESSURE SYSTEM. SHOWERS AND SCT THUNDERSTORMS ARE ANTICIPATED AHEAD OF THIS LOW PRESSURE SYSTEM TOMORROW. TIMING STILL UNCERTAIN AS VARIOUS 12Z MODELS HAVE PUSHED PRECIP BACK UNTIL THE AFTERNOON. WILL DELAY THE PRECIP UNTIL THE MORNING...BUT FUTURE TIMING CHANGES WILL LIKELY BE NEEDED. CONDITIONS TO FALL TO MVFR WITHIN SHOWERS AND TSTORMS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......RDM AVIATION.......MPC